vvEPA
United Sato
Eiwiranmifiial Pwtediofi
Agency
2006 Urban Air Toxics Monitoring Program
(UATMP) Final Report
Volume I: Main Content
December 2007
Final Report
-------
EPA-454/R-08-001a
December 2007
2006 Urban Air Toxics Monitoring Program (UATMP) Final Report
Volume I: Main Content
Prepared By:
Eastern Research Group, Inc.
Research Triangle Park, North Carolina
Prepared for:
Margaret Dougherty and Mike Jones
Office of Air Quality Planning and Standards
Research Triangle Park, NC 27711
Contract No. 68-D-03-049
Delivery Orders 06 and 09
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Emissions, Monitoring and Analysis Division
Research Triangle Park, NC 27711
-------
2006 Urban Air Toxics
Monitoring Program (UATMP)
Final Report
EPA Contract No. 68-D-03-049
Delivery Order 06
Delivery Order 09
Prepared for:
Margaret Dougherty and Mike Jones
Office of Air Quality Planning and Standards
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
Prepared by:
Eastern Research Group, Inc.
1600 Perimeter Park
Morrisville, NC 27560
December 2007
-------
DISCLAIMER
Through its Office of Air Quality Planning and Standards, the U.S. Environmental Protection
Agency funded and managed the research described in this report under EPA Contract
No. 68-D-03-049 to Eastern Research Group, Inc. This report has been subjected to the
Agency's peer and administrative review and has been approved for publication as an EPA
document. Mention of trade names or commercial products in this report does not constitute
endorsement or recommendation for their use.
11
-------
TABLE OF CONTENTS
age
List of Figures xx
List of Tables xxviii
List of Acronyms xli
Abstract xliii
1.0 Introduction 1-1
2.0 The 2006 UATMP 2-1
2.1 Monitoring Locations 2-1
2.2 Methods Used and Pollutants Targeted for Monitoring 2-30
2.2.1 VOCandSNMOC Sampling and Analytical Method 2-32
2.2.2 Carbonyl Sampling and Analytical Method 2-37
2.2.3 Semivolatile Sampling and Analytical Method 2-38
2.2.4 Metals Sampling and Analytical Method 2-43
2.2.5 Hexavalent Chromium Sampling and Analytical Method 2-44
2.3 Sample Collection Schedules 2-45
2.4 Completeness 2-52
3.0 Summary of the 2006 UATMP Data 3-1
3.1 Data Summary Parameters 3-1
3.1.1 Target Pollutant Detections 3-2
3.1.2 Concentration Range 3-16
3.1.3 Statistics 3-17
3.1.4 Risk Screening and Pollutants of Interest 3-18
3.1.5 Non-Chronic Risk 3-21
3.1.6 Pearson Correlations 3-24
3.1.6.1 Maximum and Average Temperature 3-25
3.1.6.2 Moisture 3-25
3.1.6.3 Wind and Pressure 3-27
3.2 Additional Program-Level Analyses of the 2006 UATMP Dataset 3-28
3.2.1 The Impact of Mobile Source Emissions on Spatial Variations 3-28
3.2.1.1 Motor Vehicle Ownership Data 3-29
3.2.1.2 Estimated Traffic Volume Data 3-33
3.2.1.3 Mobile Source Tracer Analysis 3-35
3.2.1.4 BETX Concentration Profiles 3-37
3.2.2 Variability Analysis 3-42
iii
-------
TABLE OF CONTENTS (Continued)
Page
3.2.2.1 Coefficient of Variation 3-42
3.2.2.2 Seasonal Variability Analysis 3-42
3.3 Additional Site-Specific Analyses 3-80
3.3.1 Emission Tracer Analysis 3-80
3.3.2 Back Trajectory Analysis 3-80
3.3.3 Wind Rose Analysis 3-81
3.3.4 Site Trends Analysis 3-81
3.3.5 Chronic Risk Assessment 3-82
3.3.6 Toxicity-Weighted Emissions Assessment 3-84
4.0 Sites in Alabama 4-1
4.1 Risk Screening and Pollutants of Interest 4-9
4.2 Concentration Averages 4-12
4.3 Non-Chronic Risk Evaluation 4-17
4.4 Meteorological and Concentration Analysis 4-26
4.4.1 Pearson Correlation Analysis 4-26
4.4.2 Composite Back Trajectory Analysis 4-31
4.4.3 Wind Rose Analysis 4-31
4.5 Spatial Characteristics Analysis 4-40
4.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 4-40
4.5.2 BTEX Analysis 4-42
4.6 Trends Analysis 4-42
4.7 Chronic Risk Analysis 4-43
4.8 Toxicity-Weighted Emissions Assessment 4-49
5.0 Site in Arizona 5-1
5.1 Risk Screening and Pollutants of Interest 5-1
5.2 Concentration Averages 5-5
5.3 Non-Chronic Risk Evaluation 5-6
5.4 Meteorological and Concentration Analysis 5-6
5.4.1 Pearson Correlation Analysis 5-8
5.4.2 Composite Back Trajectory Analysis 5-8
iv
-------
TABLE OF CONTENTS (Continued)
Page
5.4.3 Wind Rose Analysis 5-8
5.5 Spatial Characteristics Analysis 5-12
5.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 5-12
5.6 Trends Analysis 5-14
5.7 Chronic Risk Analysis 5-14
5.8 Toxicity-Weighted Emissions Assessment 5-16
6.0 Site in Colorado 6-1
6.1 Risk Screening and Pollutants of Interest 6-1
6.2 Concentration Averages 6-6
6.3 Non-Chronic Risk Evaluation 6-6
6.4 Meteorological and Concentration Analysis 6-8
6.4.1 Pearson Correlation Analysis 6-11
6.4.2 Composite Back Trajectory Analysis 6-11
6.4.3 Wind Rose Analysis 6-14
6.5 Spatial Characteristics Analysis 6-14
6.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 6-14
6.5.2 BTEX Analysis 6-17
6.6 Trends Analysis 6-17
6.7 Chronic Risk Analysis 6-19
6.8 Toxicity-Weighted Emissions Assessment 6-21
7.0 Site in Washington, D.C 7-1
7.1 Risk Screening and Pollutants of Interest 7-5
7.2 Concentration Averages 7-5
7.3 Non-Chronic Risk Evaluation 7-6
7.4 Meteorological and Concentration Analysis 7-6
7.4.1 Pearson Correlation Analysis 7-8
7.4.2 Composite Back Trajectory Analysis 7-8
v
-------
TABLE OF CONTENTS (Continued)
Page
7.4.3 Wind Rose Analysis 7-8
7.5 Spatial Characteristics Analysis 7-12
7.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 7-12
7.6 Trends Analysis 7-14
7.7 Chronic Risk Analysis 7-14
7.8 Toxicity-Weighted Emissions Assessment 7-14
8.0 Sites in Florida 8-1
8.1 Risk Screening and Pollutants of Interest 8-12
8.2 Concentration Averages 8-15
8.3 Non-Chronic Risk Evaluation 8-17
8.4 Meteorological and Concentration Analysis 8-17
8.4.1 Pearson Correlation Analysis 8-17
8.4.2 Composite Back Trajectory Analysis 8-19
8.4.3 Wind Rose Analysis 8-27
8.5 Spatial Characteristics Analysis 8-35
8.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 8-36
8.6 Trends Analysis 8-36
8.7 Chronic Risk Analysis 8-38
8.8 Toxicity-Weighted Emissions Assessment 8-46
9.0 Site in Georgia 9-1
9.1 Risk Screening and Pollutants of Interest 9-1
9.2 Concentration Averages 9-5
9.3 Non-Chronic Risk Evaluation 9-7
9.4 Meteorological and Concentration Analysis 9-7
9.4.1 Pearson Correlation Analysis 9-7
9.4.2 Composite Back Trajectory Analysis 9-7
9.4.3 Wind Rose Analysis 9-10
vi
-------
TABLE OF CONTENTS (Continued)
Page
9.5 Spatial Characteristics Analysis 9-10
9.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 9-13
9.6 Trends Analysis 9-13
9.7 Chronic Risk Analysis 9-13
9.8 Toxicity-Weighted Emissions Assessment 9-15
10.0 Sites in Illinois 10-1
10.1 Risk Screening and Pollutants of Interest 10-6
10.2 Concentration Averages 10-8
10.3 Non-Chronic Risk Evaluation 10-10
10.4 Meteorological and Concentration Analysis 10-17
10.4.1 Pearson Correlation Analysis 10-17
10.4.2 Composite Back Trajectory Analysis 10-19
10.4.3 Wind Rose Analysis 10-19
10.5 Spatial Characteristics Analysis 10-24
10.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 10-24
10.5.2 BTEX Analysis 10-26
10.5.3 Mobile Tracer Analysis 10-26
10.6 Trends Analysis 10-26
10.7 Chronic Risk Analysis 10-27
10.8 Toxicity-Weighted Emissions Assessment 10-32
11.0 Sites in Indiana 11-1
11.1 Risk Screening and Pollutants of Interest 11-9
11.2 Concentration Averages 11-10
11.3 Non-Chronic Risk Evaluation 11-11
11.4 Meteorological and Concentration Analysis 11-14
11.4.1 Pearson Correlation Analysis 11-17
11.4.2 Composite Back Trajectory Analysis 11-17
11.4.3 Wind Rose Analysis 11-22
vii
-------
TABLE OF CONTENTS (Continued)
Page
11.5 Spatial Characteristics Analysis 11-27
11.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 11-27
11.6 Trends Analysis 11-29
11.7 Chronic Risk Analysis 11-29
11.8 Toxicity-Weighted Emissions Assessment 11-31
12.0 Site in Kentucky 12-1
12.1 Risk Screening and Pollutants of Interest 12-1
12.2 Concentration Averages 12-5
12.3 Non-Chronic Risk Evaluation 12-7
12.4 Meteorological and Concentration Analysis 12-7
12.4.1 Pearson Correlation Analysis 12-7
12.4.2 Composite Back Trajectory Analysis 12-7
12.4.3 Wind Rose Analysis 12-10
12.5 Spatial Characteristics Analysis 12-10
12.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 12-10
12.6 Trends Analysis 12-13
12.7 Chronic Risk Analysis 12-13
12.8 Toxicity-Weighted Emissions Assessment 12-15
13.0 Site in Massachusetts 13-1
13.1 Risk Screening and Pollutants of Interest 13-1
13.2 Concentration Averages 13-5
13.3 Non-Chronic Risk Evaluation 13-6
13.4 Meteorological and Concentration Analysis 13-6
13.4.1 Pearson Correlation Analysis 13-8
13.4.2 Composite Back Trajectory Analysis 13-8
13.4.3 Wind Rose Analysis 13-8
13.5 Spatial Characteristics Analysis 13-11
viii
-------
TABLE OF CONTENTS (Continued)
Page
13.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 13-11
13.6 Trends Analysis 13-14
13.7 Chronic Risk Analysis 13-14
13.8 Toxicity-Weighted Emissions Assessment 13-16
14.0 Sites in Michigan 14-1
14.1 Risk Screening and Pollutants of Interest 14-6
14.2 Concentration Averages 14-8
14.3 Non-Chronic Risk Evaluation 14-9
14.4 Meteorological and Concentration Analysis 14-12
14.4.1 Pearson Correlation Analysis 14-12
14.4.2 Composite Back Trajectory Analysis 14-15
14.4.3 Wind Rose Analysis 14-18
14.5 Spatial Characteristics Analysis 14-21
14.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 14-21
14.5.2 BTEX Analysis 14-21
14.6 Trends Analysis 14-23
14.7 Chronic Risk Analysis 14-23
14.8 Toxicity-Weighted Emissions Assessment 14-27
15.0 Site in Minnesota 15-1
15.1 Risk Screening and Pollutants of Interest 15-5
15.2 Concentration Averages 15-6
15.3 Non-Chronic Risk Evaluation 15-8
15.4 Meteorological and Concentration Analysis 15-11
15.4.1 Pearson Correlation Analysis 15-11
15.4.2 Composite Back Trajectory Analysis 15-11
15.4.3 Wind Rose Analysis 15-14
15.5 Spatial Characteristics Analysis 15-14
ix
-------
TABLE OF CONTENTS (Continued)
Page
15.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 15-14
15.5.2 BTEX Analysis 15-17
15.6 Trends Analysis 15-17
15.7 Chronic Risk Analysis 15-18
15.8 Toxicity-Weighted Emissions Assessment 15-18
16.0 Sites in Mississippi 16-1
16.1 Risk Screening and Pollutants of Interest 16-7
16.2 Concentration Averages 16-8
16.3 Non-Chronic Risk Evaluation 16-9
16.4 Meteorological and Concentration Analysis 16-15
16.4.1 Pearson Correlation Analysis 16-15
16.4.2 Composite Back Trajectory Analysis 16-15
16.4.3 Wind Rose Analysis 16-19
16.5 Spatial Characteristics Analysis 16-22
16.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 16-22
16.5.2 BTEX Analysis 16-22
16.5.3 Mobile Tracer Analysis 16-24
16.6 Trends Analysis 16-24
16.7 Chronic Risk Analysis 16-25
16.8 Toxicity-Weighted Emissions Assessment 16-29
17.0 Site in Missouri 17-1
17.1 Risk Screening and Pollutants of Interest 17-1
17.2 Concentration Averages 17-6
17.3 Non-Chronic Risk Evaluation 17-8
17.4 Meteorological and Concentration Analysis 17-11
17.4.1 Pearson Correlation Analysis 17-11
17.4.2 Composite Back Trajectory Analysis 17-11
17.4.3 Wind Rose Analysis 17-14
x
-------
TABLE OF CONTENTS (Continued)
Page
17.5 Spatial Characteristics Analysis 17-14
17.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 17-14
17.5.2 BTEX Analysis 17-17
17.6 Trends Analysis 17-17
17.7 Chronic Risk Analysis 17-18
17.8 Toxicity-Weighted Emissions Assessment 17-21
18.0 Sites in New Jersey 18-1
18.1 Risk Screening and Pollutants of Interest 18-9
18.2 Concentration Averages 18-12
18.3 Non-Chronic Risk Evaluation 18-16
18.4 Meteorological and Concentration Analysis 18-23
18.4.1 Pearson Correlation Analysis 18-23
18.4.2 Composite Back Trajectory Analysis 18-26
18.4.3 Wind Rose Analysis 18-31
18.5 Spatial Characteristics Analysis 18-36
18.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 18-36
18.5.2 BTEX Analysis 18-38
18.6 Trends Analysis 18-39
18.7 Chronic Risk Analysis 18-44
18.8 Toxicity-Weighted Emissions Assessment 18-48
19.0 Sites in North Carolina 19-1
19.1 Risk Screening and Pollutants of Interest 19-7
19.2 Concentration Averages 19-8
19.3 Non-Chronic Risk Evaluation 19-10
19.4 Meteorological and Concentration Analysis 19-10
19.4.1 Pearson Correlation Analysis 19-10
19.4.2 Composite Back Trajectory Analysis 19-12
xi
-------
TABLE OF CONTENTS (Continued)
Page
19.4.3 Wind Rose Analysis 19-12
19.5 Spatial Characteristics Analysis 19-15
19.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 19-15
19.6 Trends Analysis 19-19
19.7 Chronic Risk Analysis 19-19
19.8 Toxicity-Weighted Emissions Assessment 19-22
20.0 Sites in Oklahoma 20-1
20.1 Risk Screening and Pollutants of Interest 20-9
20.2 Concentration Averages 20-11
20.3 Non-Chronic Risk Evaluation 20-12
20.4 Meteorological and Concentration Analysis 20-21
20.4.1 Pearson Correlation Analysis 20-21
20.4.2 Composite Back Trajectory Analysis 20-24
20.4.3 Wind Rose Analysis 20-29
20.5 Spatial Characteristics Analysis 20-34
20.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 20-34
20.5.2 BTEX Analysis 20-36
20.6 Trends Analysis 20-36
20.7 Chronic Risk Analysis 20-36
20.8 Toxicity-Weighted Emissions Assessment 20-40
21.0 Site in Oregon 21-1
21.1 Risk Screening and Pollutants of Interest 21-1
21.2 Concentration Averages 21-5
21.3 Non-Chronic Risk Evaluation 21-7
21.4 Meteorological and Concentration Analysis 21-7
21.4.1 Pearson Correlation Analysis 21-7
21.4.2 Composite Back Trajectory Analysis 21-9
xii
-------
TABLE OF CONTENTS (Continued)
Page
21.4.3 Wind Rose Analysis 21-9
21.5 Spatial Characteristics Analysis 21-12
21.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 21-12
21.6 Trends Analysis 21-12
21.7 Chronic Risk Analysis 21-12
21.8 Toxi city-Weighted Emissions Assessment 21-15
22.0 Sites in Puerto Rico 22-1
22.1 Risk Screening and Pollutants of Interest 22-7
22.2 Concentration Averages 22-8
22.3 Non-Chronic Risk Evaluation 22-11
22.4 Meteorological and Concentration Analysis 22-15
22.4.1 Pearson Correlation Analysis 22-15
22.4.2 Composite Back Trajectory Analysis 22-17
22.4.3 Wind Rose Analysis 22-17
22.5 Spatial Characteristics Analysis 22-22
22.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 22-22
22.5.2 BTEX Analysis 22-22
22.6 Trends Analysis 22-24
22.7 Chronic Risk Analysis 22-24
22.8 Toxicity-Weighted Emissions Assessment 22-28
23.0 Site in Rhode Island 23-1
23.1 Risk Screening and Pollutants of Interest 23-1
23.2 Concentration Averages 23-5
23.3 Non-Chronic Risk Evaluation 23-6
23.4 Meteorological and Concentration Analysis 23-6
23.4.1 Pearson Correlation Analysis 23-6
23.4.2 Composite Back Trajectory Analysis 23-9
xiii
-------
TABLE OF CONTENTS (Continued)
Page
23.4.3 Wind Rose Analysis 23-9
23.5 Spatial Characteristics Analysis 23-12
23.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 23-12
23.6 Trends Analysis 23-12
23.7 Chronic Risk Analysis 23-12
23.8 Toxicity-Weighted Emissions Assessment 23-14
24.0 Site in South Carolina 24-1
24.1 Risk Screening and Pollutants of Interest 24-5
24.2 Concentration Averages 24-5
24.3 Non-Chronic Risk Evaluation 24-6
24.4 Meteorological and Concentration Analysis 24-6
24.4.1 Pearson Correlation Analysis 24-6
24.4.2 Composite Back Trajectory Analysis 24-9
24.4.3 Wind Rose Analysis 24-9
24.5 Spatial Characteristics Analysis 24-12
24.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 24-12
24.6 Trends Analysis 24-12
24.7 Chronic Risk Analysis 24-12
24.8 Toxicity-Weighted Emissions Assessment 24-14
25.0 Sites in South Dakota 25-1
25.1 Risk Screening and Pollutants of Interest 25-7
25.2 Concentration Averages 25-8
25.3 Non-Chronic Risk Evaluation 25-11
25.4 Meteorological and Concentration Analysis 25-15
25.4.1 Pearson Correlation Analysis 25-15
25.4.2 Composite Back Trajectory Analysis 25-17
25.4.3 Wind Rose Analysis 25-17
xiv
-------
TABLE OF CONTENTS (Continued)
Page
25.5 Spatial Characteristics Analysis 25-20
25.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 25-20
25.5.2 BTEX Analysis 25-23
25.5.3 Mobile Tracer Analysis 25-25
25.6 Trends Analysis 25-25
25.7 Chronic Risk Analysis 25-27
25.8 Toxicity-Weighted Emissions Assessment 25-31
26.0 Sites in Tennessee 26-1
26.1 Risk Screening and Pollutants of Interest 26-1
26.2 Concentration Averages 26-7
26.3 Non-Chronic Risk Evaluation 26-9
26.4 Meteorological and Concentration Analysis 26-11
26.4.1 Pearson Correlation Analysis 26-11
26.4.2 Composite Back Trajectory Analysis 26-15
26.4.3 Wind Rose Analysis 26-18
26.5 Spatial Characteristics Analysis 26-18
26.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 26-18
26.5.2 BTEX Analysis 26-22
26.6 Trends Analysis 26-22
26.7 Chronic Risk Analysis 26-23
26.8 Toxicity-Weighted Emissions Assessment 26-26
27.0 Sites in Texas 27-1
27.1 Risk Screening and Pollutants of Interest 27-10
27.2 Concentration Averages 27-15
27.3 Non-Chronic Risk Evaluation 27-20
27.4 Meteorological and Concentration Analysis 27-29
27.4.1 Pearson Correlation Analysis 27-29
27.4.2 Composite Back Trajectory Analysis 27-33
xv
-------
TABLE OF CONTENTS (Continued)
Page
27.4.3 Wind Rose Analysis 27-33
27.5 Spatial Characteristics Analysis 27-40
27.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 27-40
27.5.2 BTEX Analysis 27-48
27.6 Trends Analysis 27-49
27.7 Chronic Risk Analysis 27-49
27.8 Toxicity-Weighted Emissions Assessment 27-55
28.0 Site in Utah 28-1
28.1 Risk Screening and Pollutants of Interest 28-1
28.2 Concentration Averages 28-6
28.3 Non-Chronic Risk Evaluation 28-6
28.4 Meteorological and Concentration Analysis 28-8
28.4.1 Pearson Correlation Analysis 28-11
28.4.2 Composite Back Trajectory Analysis 28-11
28.4.3 Wind Rose Analysis 28-14
28.5 Spatial Characteristics Analysis 28-14
28.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 28-14
28.5.2 BTEX Analysis 28-17
28.5.3 Mobile Tracer Analysis 28-17
28.6 Trends Analysis 28-18
28.7 Chronic Risk Analysis 28-18
28.8 Toxicity-Weighted Emissions Assessment 28-22
29.0 Site in Vermont 29-1
29.1 Risk Screening and Pollutants of Interest 29-1
29.2 Concentration Averages 29-5
29.3 Non-Chronic Risk Evaluation 29-7
29.4 Meteorological and Concentration Analysis 29-7
xvi
-------
TABLE OF CONTENTS (Continued)
Page
29.4.1 Pearson Correlation Analysis 29-7
29.4.2 Composite Back Trajectory Analysis 29-9
29.4.3 Wind Rose Analysis 29-9
29.5 Spatial Characteristics Analysis 29-12
29.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 29-12
29.6 Trends Analysis 29-12
29.7 Chronic Risk Analysis 29-12
29.8 Toxicity-Weighted Emissions Assessment 29-15
30.0 Site in Washington 30-1
30.1 Risk Screening and Pollutants of Interest 30-5
30.2 Concentration Averages 30-5
30.3 Non-Chronic Risk Evaluation 30-7
30.4 Meteorological and Concentration Analysis 30-7
30.4.1 Pearson Correlation Analysis 30-7
30.4.2 Composite Back Trajectory Analysis 30-9
30.4.3 Wind Rose Analysis 30-9
30.5 Spatial Characteristics Analysis 30-9
30.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 30-12
30.6 Trends Analysis 30-12
30.7 Chronic Risk Analysis 30-12
30.8 Toxicity-Weighted Emissions Assessment 30-15
31.0 Sites in Wisconsin 31-1
31.1 Risk Screening and Pollutants of Interest 31-7
31.2 Concentration Averages 31-8
31.3 Non-Chronic Risk Evaluation 31-10
31.4 Meteorological and Concentration Analysis 31-10
31.4.1 Pearson Correlation Analysis 31-11
xvii
-------
TABLE OF CONTENTS (Continued)
Page
31.4.2 Composite Back Trajectory Analysis 31-11
31.4.3 Wind Rose Analysis 31-15
31.5 Spatial Characteristics Analysis 31-18
31.5.1 Population, Vehicle Ownership, and Traffic Data Comparison 31-18
31.5.2 BTEX Analysis 31-18
31.6 Trends Analysis 31-20
31.7 Chronic Risk Analysis 31-20
31.8 Toxicity-Weighted Emissions Assessment 31-24
32.0 Data Quality 32-1
32.1 Precision 32-1
32.1.1 VOC Sampling and Analytical Precision 32-4
32.1.2 SNMOC Sampling and Analytical Precision 32-17
32.1.3 Carbonyl Compounds Sampling and Analytical Precision 32-34
32.1.4 Metals Sampling and Analytical Precision 32-42
32.1.5 Hexavalent Chromium Sampling and Analytical Precision 32-44
32.2 Analytical Precision 32-45
32.2.1 VOC Analytical Precision 32-46
32.2.2 SNMOC Analytical Precision 32-65
32.2.3 Carbonyl Compound Analytical Precision 32-76
32.2.4 Hexavalent Chromium Analytical Precision 32-84
32.3 Bias 32-85
32.3.1 Proficiency Test Studies 32-86
33.0 Conclusions and Recommendations 33-1
33.1 Conclusions 33-1
33.1.1 National-Level Conclusions 33-1
33.1.2 Supplementary Observations and Interpretations 33-3
33.1.3 State-Level Conclusions 33-4
33.1.4 Data Quality 33-31
33.2 Recommendations 33-32
34.0 References 34-1
xvin
-------
List of Appendices
Appendix A
Appendix B
Appendix C
Appendix D
Appendix E
Appendix F
Appendix G
Appendix H
Appendix I
Appendix J
Appendix K
Appendix L
Appendix M
Appendix N
Appendix O
TABLE OF CONTENTS (Continued)
AIRS Site Descriptions for the 2006 UATMP Monitoring Sites A-l
2006 Summary of Invalidated UATMP Samples by Site B-l
2006 Summary Tables for VOC Monitoring C-l
2006 Summary Tables for SNMOC Monitoring D-l
2006 Summary Tables of Carbonyl Monitoring E-l
2006 Summary Tables for SVOC Monitoring F-l
2006 Summary Tables for Metals Monitoring G-l
2006 Summary Tables for Hexavalent Chromium Monitoring H-l
2006 VOC Raw Monitoring Data 1-1
2006 SNMOC/TNMOC Raw Monitoring Data J-l
2006 Carbonyl Raw Monitoring Data K-l
2006 SVOC Raw Monitoring Data L-l
2006 Metal Raw Monitoring Data M-l
2006 Hexavalent Chromium Raw Monitoring Data N-l
2006 Range of Detect! on Limits O-l
xix
-------
LIST OF FIGURES
Page
2-1 Monitoring Site Locations for the 2006 UATMP 2-3
3-1 Comparison of Average Hydrocarbon Concentration vs. 10-Mile Vehicle Registration 3-32
3-2 Comparison of Average Hydrocarbon Concentration vs. Daily Traffic Volume 3-34
3-3 Comparison of Average Acetylene Concentration vs. Daily Traffic Volume 3-36
3-4 Comparison of Concentration Ratios for BTEX Compounds vs. Roadside Study 3-39
3-5 Coefficient of Variation Analysis of 1,3-Butadiene Across 34 Sites 3-43
3-6 Coefficient of Variation Analysis of Acetaldehyde Across 45 Sites 3-44
3-7 Coefficient of Variation Analysis of Acrolein Across 33 Sites 3-45
3-8 Coefficient of Variation Analysis of Benzene Across 34 Sites 3-46
3-9 Coefficient of Variation Analysis of Carbon Tetrachloride Across 34 Sites 3-47
3-10 Coefficient of Variation Analysis of Formaldehyde Across 45 Sites 3-48
3-11 Coefficient of Variation Analysis of Hexachloro-l,3-Butadiene Across 29 Sites 3-49
3-12 Coefficient of Variation Analysis of Hexavalent Chromium Across 23 Sites 3-50
3-13 Coefficient of Variation Analysis of Naphthalene Across 6 Sites 3-51
3-14 Coefficient of Variation Analysis ofp-Dichlorobenzene/l,4-Dichlorobenzene Across
35 Sites 3-52
3-15 Coefficient of Variation Analysis of Tetrachloroethylene Across 34 Sites 3-53
3-16 Coefficient of Variation Analysis of Arsenic Across 21 Sites 3-54
3-17 Coefficient of Variation Analysis of Manganese Across 21 Sites 3-55
3-18a Comparison of Average Seasonal 1,3-Butadiene Concentration by Season 3-56
3-18b Comparison of Average Seasonal 1,3-Butadiene Concentration by Season 3-57
3-19a Comparison of Average Seasonal Acetaldehyde Concentration by Season 3-58
3-19b Comparison of Average Seasonal Acetaldehyde Concentration by Season 3-59
3-20a Comparison of Average Seasonal Acrolein Concentration by Season 3-60
3-20b Comparison of Average Seasonal Acrolein Concentration by Season 3-61
3-21a Comparison of Average Seasonal Arsenic PMio Concentration by Season 3-62
3-21b Comparison of Average Seasonal Arsenic TSP Concentration by Season 3-63
3-22a Comparison of Average Seasonal Benzene Concentration by Season 3-64
3-22b Comparison of Average Seasonal Benzene Concentration by Season 3-65
3-23a Comparison of Average Seasonal Carbon Tetrachloride Concentration by Season 3-66
3-23b Comparison of Average Seasonal Carbon Tetrachloride Concentration by Season 3-67
3-24a Comparison of Average Seasonal Formaldehyde Concentration by Season 3-68
3-24b Comparison of Average Seasonal Formaldehyde Concentration by Season 3-69
3-25 Comparison of Average Seasonal Hexavalent Chromium Concentration by Season ... 3-70
3-26a Comparison of Average Seasonal Manganese PMi0 Concentration by Season 3-71
3-26b Comparison of Average Seasonal Manganese TSP Concentration by Season 3-72
3-27 Comparison of Average Seasonal Naphthalene Concentration by Season 3-73
3-28a Comparison of Average Seasonal />-Dichlorobenzene by Compendium Method TO-15
Concentration by Season 3-74
3-28b Comparison of Average Seasonal />-Dichlorobenzene by Compendium Method TO-15
Concentration by Season 3-75
3-28c Comparison of Average Seasonal 1,4-Dichlorobenzene (p-Dichlorobenzene) by
Compendium Method TO-13A Concentration by Season 3-76
3-29a Comparison of Average Seasonal Tetrachloroethylene Concentration by Season 3-77
xx
-------
LIST OF FIGURES (Continued)
Page
3-29b Comparison of Average Seasonal Tetrachloroethylene Concentration by Season 3-78
4-1 Birmingham, Alabama (ETAL) Monitoring Site 4-2
4-2 Birmingham, Alabama (NBAL) Monitoring Site 4-3
4-3 Birmingham, Alabama (PVAL) Monitoring Site 4-4
4-4 Birmingham, Alabama (SIAL) Monitoring Site 4-5
4-5 Facilities Located Within 10 Miles of ETAL, NBAL, and SIAL 4-6
4-6 Facilities Located Within 10 Miles of PVAL 4-7
4-7 Acrolein Pollution Rose for ETAL 4-20
4-8 Acrolein Pollution Rose for NBAL 4-21
4-9 Acrolein Pollution Rose for PVAL 4-22
4-10 Acrolein Pollution Rose for SIAL 4-23
4-11 Benzene Pollution Rose for SIAL 4-24
4-12 Composite Back Trajectory Map for ETAL 4-32
4-13 Composite Back Trajectory Map for NBAL 4-33
4-14 Composite Back Trajectory Map for PVAL 4-34
4-15 Composite Back Trajectory Map for SIAL 4-35
4-16 Wind Rose for ETAL SamplingDays 4-36
4-17 Wind Rose for NBAL SamplingDays 4-37
4-18 Wind Rose for PVAL SamplingDays 4-38
4-19 Wind Rose for SIAL Sampling Days 4-39
5-1 Phoenix, Arizona (PXSS) Monitoring Site 5-2
5-2 Facilities Located Within 10 Miles of PXSS 5-3
5-3 Composite Back Trajectory Map for PXSS 5-10
5-4 Wind Rose for PXSS SamplingDays 5-11
6-1 Grand Junction, Colorado (GPCO) Monitoring Site 6-2
6-2 Facilities Located Within 10 Miles of GPCO 6-3
6-3 Acrolein Pollution Rose for GPCO 6-10
6-4 Composite Back Trajectory Map for GPCO 6-13
6-5 Wind Rose for GPCO Sampling Days 6-15
6-6 Comparison of Yearly Averages for the GPCO Monitoring Site 6-18
7-1 Washington, D.C. (WADC) Monitoring Site 7-2
7-2 Facilities Located Within 10 Miles of WADC 7-3
7-3 Composite Back Trajectory Map for WADC 7-10
7-4 Wind Rose for WADC SamplingDays 7-11
8-1 Tampa/St. Petersburg, Florida (AZFL) Monitoring Site 8-2
8-2 Tampa/St. Petersburg, Florida (GAFL) Monitoring Site 8-3
8-3 Tampa/St. Petersburg, Florida (SKFL) Monitoring Site 8-4
8-4 Tampa/St. Petersburg, Florida (SMFL) Monitoring Site 8-5
8-5 Tampa/St. Petersburg, Florida (SYFL) Monitoring Site 8-6
8-6 Ft. Lauderdale, Florida (FLFL) Monitoring Site 8-7
xxi
-------
LIST OF FIGURES (Continued)
Page
8-7 Orlando, Florida (ORFL) Monitoring Site 8-8
8-8 Facilities Located Within 10 Miles of the Tampa/St. Petersburg, Florida
Monitoring Sites 8-9
8-9 Facilities Located Within 10 Miles of FLFL 8-10
8-10 Facilities Located Within 10 Miles of ORFL 8-11
8-11 Composite Back Trajectory Map for AZFL 8-20
8-12 Composite Back Trajectory Map for GAFL 8-21
8-13 Composite Back Trajectory Map for SKFL 8-22
8-14 Composite Back Trajectory Map for SMFL 8-23
8-15 Composite Back Trajectory Map for SYFL 8-24
8-16 Composite Back Trajectory Map for FLFL 8-25
8-17 Composite Back Trajectory Map for ORFL 8-26
8-18 Wind Rose for AZFL Sampling Days 8-28
8-19 Wind Rose for GAFL Sampling Days 8-29
8-20 Wind Rose for SKFL Sampling Days 8-30
8-21 Wind Rose for SMFL Sampling Days 8-31
8-22 Wind Rose for SYFL Sampling Days 8-32
8-23 Wind Rose for FLFL SamplingDays 8-33
8-24 Wind Rose for ORFL SamplingDays 8-34
8-25 Comparison of Yearly Averages for the AZFL Monitoring Site 8-39
8-26 Comparison of Yearly Averages for the GAFL Monitoring Site 8-40
8-27 Comparison of Yearly Averages for the ORFL Monitoring Site 8-41
8-28 Comparison of Yearly Averages for the SKFL Monitoring Site 8-42
8-29 Comparison of Yearly Averages for the SYFL Monitoring Site 8-43
9-1 Decatur, Georgia (SDGA) Monitoring Site 9-2
9-2 Facilities Located Within 10 Miles of SDGA 9-3
9-3 Composite Back Trajectory Map for SDGA 9-9
9-4 Wind Rose for SDGA Sampling Days 9-11
10-1 Chicago, Illinois (NBIL) Monitoring Site 10-2
10-2 Chicago, Illinois (SPIL) Monitoring Site 10-3
10-3 Facilities Located Within 10 Miles of NBIL and SPIL 10-4
10-4 Acrolein Pollution Rose for NBIL 10-13
10-5 Acrolein Pollution Rose for SPIL 10-14
10-6 Formaldehyde Pollution Rose for NBIL 10-15
10-7 Formaldehyde Pollution Rose for SPIL 10-16
10-8 Composite Back Trajectory Map for NBIL 10-20
10-9 Composite Back Trajectory Map for SPIL 10-21
10-10 Wind Rose for NBIL Sampling Days 10-22
10-11 Wind Rose for SPIL SamplingDays 10-23
10-12 Comparison of Yearly Averages for the NBIL Monitoring Site 10-28
10-13 Comparison of Yearly Averages for the SPIL Monitoring Site 10-29
11-1 Indianapolis, Indiana (IDIN) Monitoring Site 11-2
xxii
-------
LIST OF FIGURES (Continued)
Page
11-2 Gary, Indiana (INDEM) Monitoring Site 11-3
11-3 Indianapolis, Indiana (ININ) Monitoring Site 11-4
11-4 Indianapolis, Indiana (WPIN) Monitoring Site 11-5
11-5 Facilities Located Within 10 Miles of IDIN, ININ, and WPIN 11-6
11-6 Facilities Located Within 10 Miles of INDEM 11-7
11-7 Formaldehyde Pollution Rose for INDEM 11-15
11-8 Composite Back Trajectory Map for IDIN 11-18
11-9 Composite Back Trajectory Map for INDEM 11-19
11-10 Composite Back Trajectory Map for ININ 11-20
11-11 Composite Back Trajectory Map for WPIN 11-21
11-12 Wind Rose for IDIN Sampling Days 11-23
11-13 Wind Rose for INDEM Sampling Days 11-24
11-14 Wind Rose for ININ Sampling Days 11-25
11-15 Wind Rose for WPIN Sampling Days 11-26
11-16 Comparison of Yearly Averages for the INDEM Monitoring Site 11-30
12-1 Hazard, Kentucky (HAKY) Monitoring Site 12-2
12-2 Facilities Located WithinlO Miles of HAKY 12-3
12-3 Composite Back Trajectory Map for HAKY 12-9
12-4 Wind Rose for HAKY Sampling Days 12-11
13-1 Boston, Massachusetts (BOMA) Monitoring Site 13-2
13-2 Facilities Located WithinlO Miles of BOMA 13-3
13-3 Composite Back Trajectory Map for BOMA 13-10
13-4 Wind Rose for BOMA Sampling Days 13-12
14-1 Detroit, Michigan (DEMI) Monitoring Site 14-2
14-2 Sault Saint Marie, Michigan (ITCMI) Monitoring Site 14-3
14-3 Facilities Located Within 10 Miles of DEMI 14-4
14-4 Facilities Located Within 10 Miles of ITCMI 14-5
14-5 Acrolein Pollution Rose for DEMI 14-13
14-6 Composite Back Trajectory Map for DEMI 14-16
14-7 Composite Back Trajectory Map for ITCMI 14-17
14-8 Wind Rose for DEMI Sampling Days 14-19
14-9 Wind Rose for ITCMI Sampling Days 14-20
14-10 Comparison of Yearly Averages for the DEMI Monitoring Site 14-24
15-1 Minneapolis, Minnesota (MIMN) Monitoring Site 15-2
15-2 Facilities Located Within 10 Miles of MIMN 15-3
15-3 Acrolein Pollution Rose for MIMN 15-10
15-4 Composite Back Trajectory Map for MEVIN 15-13
15-5 Wind Rose for MIMN Sampling Days 15-15
16-1 Gulfport, Mississippi (GPMS) Monitoring Site 16-2
16-2 Tupelo, Mississippi (TUMS) Monitoring Site 16-3
xxiii
-------
LIST OF FIGURES (Continued)
Page
16-3 Facilities Located Within 10 Miles of GPMS 16-4
16-4 Facilities Located Within 10 Miles of TUMS 16-5
16-5 Acrolein Pollution Rose for GPMS 16-13
16-6 Acrolein Pollution Rose for TUMS 16-14
16-7 Composite Back Trajectory Map for GPMS 16-17
16-8 Composite Back Trajectory Map for TUMS 16-18
16-9 Wind Rose for GPMS Sampling Days 16-20
16-10 Wind Rose for TUMS Sampling Days 16-21
16-11 Comparison of Yearly Averages for the GPMS Monitoring Site 16-26
16-12 Comparison of Yearly Averages for the TUMS Monitoring Site 16-27
17-1 St. Louis, Missouri (S4MO) Monitoring Site 17-2
17-2 Facilities Located Within 10 Miles of S4MO 17-3
17-3 Acrolein Pollution Rose for S4MO 17-10
17-4 Composite Back Trajectory Map for S4MO 17-13
17-5 Wind Rose for S4MO Sampling Days 17-15
17-6 Comparison of Yearly Averages for the S4MO Monitoring Site 17-19
18-1 Camden, New Jersey (CANJ) Monitoring Site 18-2
18-2 Chester, New Jersey (CFINJ) Monitoring Site 18-3
18-3 Elizabeth, New Jersey (ELNJ) Monitoring Site 18-4
18-4 New Brunswick, New Jersey (NBNJ) Monitoring Site 18-5
18-5 Facilities Located Within 10 Miles of CANJ 18-6
18-6 Facilities Located Within 10 Miles of CFINJ 18-7
18-7 Facilities Located Within 10 Miles of ELNJ and NBNJ 18-8
18-8 Acrolein Pollution Rose for CANJ 18-19
18-9 Acrolein Pollution Rose for CFINJ 18-20
18-10 Acrolein Pollution Rose for ELNJ 18-21
18-11 Acrolein Pollution Rose for NBNJ 18-22
18-12 Composite Back Trajectory Map for CANJ 18-27
18-13 Composite Back Trajectory Map for CHNJ 18-28
18-14 Composite Back Trajectory Map for ELNJ 18-29
18-15 Composite Back Trajectory Map for NBNJ 18-30
18-16 Wind Rose for CANJ Sampling Days 18-32
18-17 Wind Rose for CHNJ Sampling Days 18-33
18-18 Wind Rose for ELNJ Sampling Days 18-34
18-19 Wind Rose for NBNJ Sampling Days 18-35
18-20 Comparison of Yearly Averages for the CANJ Monitoring Site 18-40
18-21 Comparison of Yearly Averages for the CHNJ Monitoring Site 18-41
18-22 Comparison of Yearly Averages for the ELNJ Monitoring Site 18-42
18-23 Comparison of Yearly Averages for the NBNJ Monitoring Site 18-43
19-1 Candor, North Carolina (CANC) Monitoring Site 19-2
19-2 Research Triangle Park, North Carolina (RTPNC) Monitoring Site 19-3
19-3 Facilities Located Within 10 Miles of CANC 19-4
19-4 Facilities Located Within 10 Miles of RTPNC 19-5
xxiv
-------
LIST OF FIGURES (Continued)
Page
19-5 Composite Back Trajectory Map for CANC 19-13
19-6 Composite Back Trajectory Map for RTPNC 19-14
19-7 Wind Rose for CANC Sampling Days 19-16
19-8 Wind Rose for RTPNC Sampling Days 19-17
19-9 Comparison of Yearly Averages for the CANC Monitoring Site 19-20
19-10 Comparison of Yearly Averages for the RTPNC Monitoring Site 19-21
20-1 Cherokee Nation, Oklahoma (CNEP) Monitoring Site 20-2
20-2 Tulsa, Oklahoma (TOOK) Monitoring Site 20-3
20-3 Tulsa, Oklahoma (TSOK) Monitoring Site 20-4
20-4 Tulsa, Oklahoma (TUOK) Monitoring Site 20-5
20-5 Facilities Located Within 10 Miles of CNEP 20-6
20-6 Facilities Located Within 10 Miles of TOOK, TSOK, and TUOK 20-7
20-7 Acrolein Pollution Rose for CNEP 20-17
20-8 Acrolein Pollution Rose for TOOK 20-18
20-9 Acrolein Pollution Rose for TSOK 20-19
20-10 Acrolein Pollution Rose for TUOK 20-20
20-11 Composite Back Trajectory Map for CNEP 20-25
20-12 Composite Back Trajectory Map for TOOK 20-26
20-13 Composite Back Trajectory Map for TSOK 20-27
20-14 Composite Back Trajectory Map for TUOK 20-28
20-15 Wind Rose for CNEP Sampling Days 20-30
20-16 Wind Rose for TOOK Sampling Days 20-31
20-17 Wind Rose for TSOK Sampling Days 20-32
20-18 Wind Rose for TUOK Sampling Days 20-33
21-1 La Grande, Oregon (LAOR) Monitoring Site 21-2
21-2 Facilities Located Within 10 Miles of LAOR 21-3
21-3 Composite Back Trajectory Map for LAOR 21-10
21-4 Wind Rose for LAOR Sampling Days 21-11
22-1 Barceloneta, Puerto Rico (BAPR) Monitoring Site 22-2
22-2 San Juan, Puerto Rico (SJPR) Monitoring Site 22-3
22-3 Facilities Located Within 10 Miles of BAPR 22-4
22-4 Facilities Located Within 10 Miles of SJPR 22-5
22-5 Acrolein Pollution Rose for BAPR 22-13
22-6 Acrolein Pollution Rose for SJPR 22-14
22-7 Composite Back Trajectory Map for BAPR 22-18
22-8 Composite Back Trajectory Map for SJPR 22-19
22-9 Wind Rose for BAPR Sampling Days 22-20
22-10 Wind Rose for SJPR Sampling Days 22-21
23-1 Providence, Rhode Island (PRRI) Monitoring Site 23-2
23-2 Facilities Located Within 10 Miles of PRRI 23-3
23-3 Composite Back Trajectory Map for PRRI 23-10
XXV
-------
LIST OF FIGURES (Continued)
Page
23-4 Wind Rose for PRRI Sampling Days 23-11
24-1 Chesterfield, South Carolina (CHSC) Monitoring Site 24-2
24-2 Facilities Located Within 10 Miles of CHSC 24-3
24-3 Composite Back Trajectory Map for CHSC 24-10
24-4 Wind Rose for CHSC Sampling Days 24-11
25-1 Custer, South Dakota (CUSD) Monitoring Site 25-2
25-2 Sioux Falls, South Dakota (SFSD) Monitoring Site 25-3
25-3 Facilities Located Within 10 Miles of CUSD 25-4
25-4 Facilities Located Within 10 Miles of SFSD 25-5
25-5 Acrolein Pollution Rose for CUSD 25-13
25-6 Acrolein Pollution Rose for SFSD 25-14
25-7 Composite Back Trajectory Map for CUSD 25-18
25-8 Composite Back Trajectory Map for SFSD 25-19
25-9 Wind Rose for CUSD Sampling Days 25-21
25-10 Wind Rose for SFSD Sampling Days 25-22
25-11 Comparison of Yearly Averages for the CUSD Monitoring Site 25-26
25-12 Comparison of Yearly Averages for the SFSD Monitoring Site 25-28
26-1 Loudon, Tennessee (LDTN) Monitoring Site 26-2
26-2 Loudon, Tennessee (MSTN) Monitoring Site 26-3
26-3 Facilities Located Within 10 Miles of LDTN and MSTN 26-4
26-4 Acrolein Pollution Rose for LDTN 26-12
26-5 Acrolein Pollution Rose for MSTN 26-13
26-6 Composite Back Trajectory Map for LDTN 26-16
26-7 Composite Back Trajectory Map for MSTN 26-17
26-8 Wind Rose for LDTN Sampling Days 26-19
26-9 Wind Rose for MSTN Sampling Days 26-20
26-10 Comparison of Yearly Averages for the LDTN Monitoring Site 26-24
27-1 Austin, Texas (MUTX) Monitoring Site 27-2
27-2 Austin, Texas (PITX) Monitoring Site 27-3
27-3 Round Rock, Texas (RRTX) Monitoring Site 27-4
27-4 Austin, Texas (TRTX) Monitoring Site 27-5
27-5 Austin, Texas (WETX) Monitoring Site 27-6
27-6 El Paso, Texas (YDSP) Monitoring Site 27-7
27-7 Facilities Located Within 10 Miles of MUTX, PITX, RRTX, TRTX, and WETX 27-8
27-8 Facilities Located Within 10 Miles of YDSP 27-9
27-9 Acrolein Pollution Rose for MUTX 27-22
27-10 Acrolein Pollution Rose for PITX 27-23
27-11 Acrolein Pollution Rose for RRTX 27-24
27-12 Acrolein Pollution Rose for TRTX 27-25
27-13 Acrolein Pollution Rose for WETX 27-26
27-14 Acrolein Pollution Rose for YDSP 27-27
xxvi
-------
LIST OF FIGURES (Continued)
Page
27-15 Composite Back Trajectory Map for MUTX 27-34
27-16 Composite Back Trajectory Map for PITX 27-35
27-17 Composite Back Trajectory Map for RRTX 27-36
27-18 Composite Back Trajectory Map for TRTX 27-37
27-19 Composite Back Trajectory Map for WETX 27-38
27-20 Composite Back Trajectory Map for YDSP 27-39
27-21 Wind Rose for MUTX Sampling Days 27-41
27-22 Wind Rose for PITX Sampling Days 27-42
27-23 Wind Rose for RRTX Sampling Days 27-43
27-24 Wind Rose for TRTX Sampling Days 27-44
27-25 Wind Rose for WETX Sampling Days 27-45
27-26 Wind Rose for YDSP Sampling Days 27-46
28-1 Bountiful, Utah (BTUT) Monitoring Site 28-2
28-2 Facilities Located Within 10 Miles of BTUT 28-3
28-3 Acrolein Pollution Rose for BTUT 28-10
28-4 Composite Back Trajectory Map for BTUT 28-13
28-5 Wind Rose for BTUT Sampling Days 28-15
28-6 Comparison of Yearly Averages for the BTUT Monitoring Site 28-19
29-1 Underbill, Vermont (UNVT) Monitoring Site 29-2
29-2 Facilities Located Within 10 Miles of UNVT 29-3
29-3 Composite Back Trajectory Map for UNVT 29-10
29-4 Wind Rose for UNVT Sampling Days 29-11
30-1 Seattle, Washington (SEWA) Monitoring Site 30-2
30-2 Facilities Located Within 10 Miles of SEW A 30-3
30-3 Composite Back Trajectory Map for SEW A 30-10
30-4 Wind Rose for SEWA Sampling Days 30-11
31-1 Madison, Wisconsin (MAWI) Monitoring Site 31-2
31-2 Mayville, Wisconsin (MVWI) Monitoring Site 31-3
31-3 Facilities Located Within 10 Miles of MAWI 31-4
31-4 Facilities Located Within 10 Miles of MVWI 31-5
31-5 Composite Back Trajectory Map for MAWI 31-13
31-6 Composite Back Trajectory Map for MVWI 31-14
31-7 Wind Rose for MAWI Sampling Days 31-16
31-8 Wind Rose for MVWI Sampling Days 31-17
31-9 Comparison of Yearly Averages for the MAWI Monitoring Site 31-21
xxvn
-------
LIST OF TABLES
Page
1-1 Organization of the 2006 UATMP Report 1-3
2-1 Descriptions of the 2006 UATMP Monitoring Sites 2-4
2-2 Site Information for the 2006 UATMP Monitoring Sites 2-21
2-3 Current UATMP Monitoring Sites with Past Participation 2-26
2-4 VOC Method Detection Limits 2-33
2-5 SNMOC Method Detection Limits 2-35
2-6 Carbonyl Method Detection Limits 2-39
2-7a S VOC (TO-13 A) Method Detect!on Limits 2-40
2-7b SVOC (SW846/8270C) Method Detection Limits 2-40
2-8 Metals Method Detection Limits 2-44
2-9 Hexavalent Chromium Method Detection Limit 2-45
2-10 Sampling Schedules and Completeness 2-46
3-1 Statistical Summaries of the VOC Concentrations 3-3
3-2 Statistical Summaries of the Carbonyl Compound Concentrations 3-5
3-3a Statistical Summaries of the SVOC (Method TO-13A) Concentrations 3-6
3-3b Statistical Summaries of the SVOC (Method 8270C) Concentrations 3-7
3-4 Statistical Summaries of the SNMOC Concentrations 3-11
3-5 Statistical Summaries of the Metals Concentrations 3-14
3-6 Statistical Summaries of the Hexavalent Chromium Concentrations 3-15
3-7 Program-Level Risk Screening Summary 3-20
3-8 Program-Level Non-Chronic Risk Summary 3-23
3-9 Summary of Pearson Correlation between the Pollutants of Interest and Selected
Meteorological Parameters 3-26
3-10 Summary of Mobile Source Information by Monitoring Site 3-30
3-11 Average Ethylene to Acetylene Ratios for Sites that Measured SNMOC 3-35
3-12 Comparison of Concentration Ratios for BTEX Compounds vs. Roadside Study 3-38
4-1 Average Meteorological Conditions near the Monitoring Sites in Alabama 4-8
4-2 Comparison of Measured Concentrations and EPA Screening Values for the Alabama
Monitoring Sites 4-10
4-3 Daily and Seasonal Averages for the Pollutants of Interest for the Alabama
Monitoring Sites 4-14
4-4 Non-Chronic Risk Summary for the Alabama Monitoring Sites 4-18
4-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Alabama Monitoring Sites 4-27
4-6 Motor Vehicle Information for the Alabama Monitoring Sites 4-41
4-7 Chronic Risk Summary for the Monitoring Sites in Alabama 4-44
4-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in Alabama 4-50
4-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in Alabama 4-52
xxvin
-------
LIST OF TABLES (Continued)
Page
5-1 Average Meteorological Conditions near the Monitoring Site in Arizona 5-4
5-2 Comparison of Measured Concentrations and EPA Screening Values for the Arizona
Monitoring Site 5-5
5-3 Daily and Seasonal Averages for the Pollutants of Interest for the Arizona Monitoring
Site 5-7
5-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Arizona Monitoring Site 5-9
5-5 Motor Vehicle Information for the Arizona Monitoring Site 5-13
5-6 Chronic Risk Summary for the Monitoring Site in Arizona 5-15
5-7 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for PXSS 5-17
5-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for PXSS 5-18
6-1 Average Meteorological Conditions near the Monitoring Site in Colorado 6-4
6-2 Comparison of Measured Concentrations and EPA Screening Values for the Colorado
Monitoring Site 6-5
6-3 Daily and Seasonal Averages for the Pollutants of Interest for the Colorado Monitoring
Site 6-7
6-4 Non-Chronic Risk Summary for the Colorado Monitoring Site 6-9
6-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Colorado Monitoring Site 6-12
6-6 Motor Vehicle Information for the Colorado Monitoring Site 6-16
6-7 Chronic Risk Summary for the Monitoring Site in Colorado 6-20
6-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for GPCO 6-22
6-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for GPCO 6-23
7-1 Average Meteorological Conditions near the Monitoring Site in Washington, D.C 7-4
7-2 Comparison of Measured Concentrations and EPA Screening Values for the Washington,
D.C. Monitoring Site 7-5
7-3 Daily and Seasonal Averages for the Pollutants of Interest for the Washington, D.C.
Monitoring Site 7-7
7-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Washington, D.C. Monitoring Site 7-9
7-5 Motor Vehicle Information for the Washington, D.C. Monitoring Site 7-13
7-6 Chronic Risk Summary for the Monitoring Site in Washington, D.C 7-15
7-7 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for WADC 7-16
7-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for WADC 7-17
XXIX
-------
LIST OF TABLES (Continued)
Page
8-1 Average Meteorological Conditions near the Monitoring Sites in Florida 8-13
8-2 Comparison of Measured Concentrations and EPA Screening Values for the Florida
Monitoring Sites 8-14
8-3 Daily and Seasonal Averages for the Pollutants of Interest for the Florida
Monitoring Sites 8-16
8-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Florida Monitoring Sites 8-18
8-5 Motor Vehicle Information for the Florida Monitoring Sites 8-37
8-6 Chronic Risk Summary for the Monitoring Sites in Florida 8-45
8-7 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Florida Monitoring Sites 8-47
8-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Florida Monitoring Sites 8-51
9-1 Average Meteorological Conditions near the Monitoring Site in Georgia 9-4
9-2 Comparison of Measured Concentrations and EPA Screening Values for the Georgia
Monitoring Site 9-5
9-3 Daily and Seasonal Averages for the Pollutants of Interest for the Georgia
Monitoring Site 9-6
9-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Georgia Monitoring Site 9-8
9-5 Motor Vehicle Information for the Georgia Monitoring Site 9-12
9-6 Chronic Risk Summary for the Monitoring Site in Georgia 9-14
9-7 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for SDGA 9-16
9-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for SDGA 9-17
10-1 Average Meteorological Conditions near the Monitoring Sites in Illinois 10-5
10-2 Comparison of Measured Concentrations and EPA Screening Values for the Illinois
Monitoring Sites 10-7
10-3 Daily and Seasonal Averages for the Pollutants of Interest for the Illinois
Monitoring Sites 10-9
10-4 Non-Chronic Risk Summary for the Illinois Monitoring Sites 10-11
10-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Illinois Monitoring Sites 10-18
10-6 Motor Vehicle Information for the Illinois Monitoring Sites 10-25
10-7 Chronic Risk Summary for the Monitoring Sites in Illinois 10-30
10-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in Illinois 10-33
10-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in Illinois 10-34
11-1 Average Meteorological Conditions near the Monitoring Sites in Indiana 11-8
XXX
-------
LIST OF TABLES (Continued)
Page
11-2 Comparison of Measured Concentrations and EPA Screening Values for the Indiana
Monitoring Sites 11-10
11-3 Daily and Seasonal Averages for the Pollutants of Interest for the Indiana
Monitoring Sites 11-12
11-4 Non-Chronic Risk Summary for the Indiana Monitoring Sites 11-13
11-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Indiana Monitoring Sites 11-16
11-6 Motor Vehicle Information for the Indiana Monitoring Sites 11-28
11-7 Chronic Risk Summary for the Monitoring Sites in Indiana 11-32
11-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in Indiana 11-34
11-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in Indiana 11-35
12-1 Average Meteorological Conditions near the Monitoring Site in Kentucky 12-4
12-2 Comparison of Measured Concentrations and EPA Screening Values for the
Kentucky Monitoring Site 12-5
12-3 Daily and Seasonal Averages for the Pollutants of Interest for the Kentucky
Monitoring Site 12-6
12-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Kentucky Monitoring Site 12-8
12-5 Motor Vehicle Information for the Kentucky Monitoring Site 12-12
12-6 Chronic Risk Summary for the Monitoring Site in Kentucky 12-14
12-7 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for HAKY 12-16
12-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for HAKY 12-17
13-1 Average Meteorological Conditions near the Monitoring Site in Massachusetts 13-4
13-2 Comparison of Measured Concentrations and EPA Screening Values for the
Massachusetts Monitoring Site 13-5
13-3 Daily and Seasonal Averages for the Pollutants of Interest for the Massachusetts
Monitoring Site 13-7
13-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Massachusetts Monitoring Site 13-9
13-5 Motor Vehicle Information for the Massachusetts Monitoring Site 13-13
13-6 Chronic Risk Summary for the Monitoring Site in Massachusetts 13-15
13-7 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for BOMA 13-17
13-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for BOMA 13-18
14-1 Average Meteorological Conditions near the Monitoring Sites in Michigan 14-7
14-2 Comparison of Measured Concentrations and EPA Screening Values for the Michigan
Monitoring Sites 14-8
xxxi
-------
LIST OF TABLES (Continued)
Page
14-3 Daily and Seasonal Averages for the Pollutants of Interest for the Michigan
Monitoring Sites 14-10
14-4 Non-Chronic Risk Summary for the Michigan Monitoring Sites 14-11
14-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Michigan Monitoring Sites 14-14
14-6 Motor Vehicle Information for the Michigan Monitoring Sites 14-22
14-7 Chronic Risk Summary for the Monitoring Sites in Michigan 14-26
14-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in Michigan 14-28
14-9 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in Michigan 14-29
15-1 Average Meteorological Conditions near the Monitoring Site in Minnesota 15-4
15-2 Comparison of Measured Concentrations and EPA Screening Values for the Minnesota
Monitoring Site 15-5
15-3 Daily and Seasonal Averages for the Pollutants of Interest for the Minnesota
Monitoring Site 15-7
15-4 Non-Chronic Risk Summary for the Minnesota Monitoring Site 15-9
15-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Minnesota Monitoring Site 15-12
15-6 Motor Vehicle Information for the Minnesota Monitoring Site 15-16
15-7 Chronic Risk Summary for the Monitoring Site in Minnesota 15-19
15-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for MIMN 15-20
15-9 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for MIMN 15-21
16-1 Average Meteorological Conditions near the Monitoring Sites in Mississippi 16-6
16-2 Comparison of Measured Concentrations and EPA Screening Values for the Mississippi
Monitoring Sites 16-8
16-3 Daily and Seasonal Averages for the Pollutants of Interest for the Mississippi
Monitoring Sites 16-10
16-4 Non-Chronic Risk Summary for the Mississippi Monitoring Sites 16-12
16-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Mississippi Monitoring Sites 16-16
16-6 Motor Vehicle Information for the Mississippi Monitoring Sites 16-23
16-7 Chronic Risk Summary for the Monitoring Sites in Mississippi 16-28
16-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in Mississippi 16-30
16-9 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in Mississippi 16-32
17-1 Average Meteorological Conditions near the Monitoring Site in Missouri 17-4
17-2 Comparison of Measured Concentrations and EPA Screening Values for the Missouri
Monitoring Site 17-5
xxxii
-------
LIST OF TABLES (Continued)
Page
17-3 Daily and Seasonal Averages for the Pollutants of Interest for the Missouri
Monitoring Site 17-7
17-4 Non-Chronic Risk Summary for the Missouri Monitoring Site 17-9
17-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Missouri Monitoring Site 17-12
17-6 Motor Vehicle Information for the Missouri Monitoring Site 17-16
17-7 Chronic Risk Summary for the Monitoring Site in Missouri 17-20
17-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Site in Missouri 17-22
17-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Site in Missouri 17-23
18-1 Average Meteorological Conditions near the Monitoring Sites in New Jersey 18-10
18-2 Comparison of Measured Concentrations and EPA Screening Values for the New Jersey
Monitoring Sites 18-11
18-3 Daily and Seasonal Averages for the Pollutants of Interest for the New Jersey
Monitoring Sites 18-14
18-4 Non-Chronic Risk Summary for the New Jersey Monitoring Sites 18-17
18-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the New Jersey Monitoring Sites 18-24
18-6 Motor Vehicle Information for the New Jersey Monitoring Sites 18-37
18-7 Chronic Risk Summary for the Monitoring Sites in New Jersey 18-45
18-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in New Jersey 18-49
18-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in New Jersey 18-51
19-1 Average Meteorological Conditions near the Monitoring Sites in North Carolina 19-6
19-2 Comparison of Measured Concentrations and EPA Screening Values for the North
Carolina Monitoring Sites 19-7
19-3 Daily and Seasonal Averages for the Pollutants of Interest for the North Carolina
Monitoring Sites 19-9
19-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the North Carolina Monitoring Sites 19-11
19-5 Motor Vehicle Information for the North Carolina Monitoring Sites 19-18
19-6 Chronic Risk Summary for the Monitoring Sites in North Carolina 19-23
19-7 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in North Carolina 19-24
19-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in North Carolina 19-25
20-1 Average Meteorological Conditions near the Monitoring Sites in Oklahoma 20-8
20-2 Comparison of Measured Concentrations and EPA Screening Values for the Oklahoma
Monitoring Sites 20-10
xxxin
-------
LIST OF TABLES (Continued)
Page
20-3 Daily and Seasonal Averages for the Pollutants of Interest for the Oklahoma
Monitoring Sites 20-13
20-4 Non-Chronic Risk Summary for the Oklahoma Monitoring Sites 20-16
20-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Oklahoma Monitoring Sites 20-22
20-6 Motor Vehicle Information for the Oklahoma Monitoring Sites 20-3 5
20-7 Chronic Risk Summary for the Monitoring Sites in Oklahoma 20-37
20-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in Oklahoma 20-41
20-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in Oklahoma 20-43
21-1 Average Meteorological Conditions near the Monitoring Site in Oregon 21-4
21-2 Comparison of Measured Concentrations and EPA Screening Values for the Oregon
Monitoring Site 21-5
21-3 Daily and Seasonal Averages for the Pollutants of Interest for the Oregon
Monitoring Site 21-6
21-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Oregon Monitoring Site 21-8
21-5 Motor Vehicle Information for the Oregon Monitoring Site 21-13
21-6 Chronic Risk Summary for the Monitoring Site in Oregon 21-14
21-7 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for LAOR 21-16
21-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for LAOR 21-17
22-1 Average Meteorological Conditions near the Monitoring Sites in Puerto Rico 22-6
22-2 Comparison of Measured Concentrations and EPA Screening Values for the Puerto Rico
Monitoring Sites 22-7
22-3 Daily and Seasonal Averages for the Pollutants of Interest for the Puerto Rico
Monitoring Sites 22-10
22-4 Non-Chronic Risk Summary for the Puerto Rico Monitoring Sites 22-12
22-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Puerto Rico Monitoring Sites 22-16
22-6 Motor Vehicle Information for the Puerto Rico Monitoring Sites 22-23
22-7 Chronic Risk Summary for the Monitoring Sites in Puerto Rico 22-25
22-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in Puerto Rico 22-29
22-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in Puerto Rico 22-30
23-1 Average Meteorological Conditions near the Monitoring Site in Rhode Island 23-4
23-2 Comparison of Measured Concentrations and EPA Screening Values for the
Rhode Island Monitoring Site 23-5
xxxiv
-------
LIST OF TABLES (Continued)
Page
23-3 Daily and Seasonal Averages for the Pollutants of Interest for the Rhode Island
Monitoring Site 23-7
23-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Rhode Island Monitoring Site 23-8
23-5 Motor Vehicle Information for the Rhode Island Monitoring Site 23-13
23-6 Chronic Risk Summary for the Monitoring Site in Rhode Island 23-15
23-7 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for PRRI 23-16
23-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for PRRI 23-17
24-1 Average Meteorological Conditions near the Monitoring Site in South Carolina 24-4
24-2 Comparison of Measured Concentrations and EPA Screening Values for the
South Carolina Monitoring Site 24-5
24-3 Daily and Seasonal Averages for the Pollutants of Interest for the South Carolina
Monitoring Site 24-7
24-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the South Carolina Monitoring Site 24-8
24-5 Motor Vehicle Information for the South Carolina Monitoring Site 24-13
24-6 Chronic Risk Summary for the Monitoring Site in South Carolina 24-15
24-7 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for CHSC 24-16
24-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for CHSC 24-17
25-1 Average Meteorological Conditions near the Monitoring Sites in South Dakota 25-6
25-2 Comparison of Measured Concentrations and EPA Screening Values for the
South Dakota Monitoring Sites 25-7
25-3 Daily and Seasonal Averages for the Pollutants of Interest for the South Dakota
Monitoring Sites 25-10
25-4 Non-Chronic Risk Summary for the South Dakota Monitoring Sites 25-12
25-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the South Dakota Monitoring Sites 25-16
25-6 Motor Vehicle Information for the South Dakota Monitoring Sites 25-24
25-7 Chronic Risk Summary for the Monitoring Sites in South Dakota 25-29
25-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in South Dakota 24-32
25-9 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in South Dakota 24-33
26-1 Average Meteorological Conditions near the Monitoring Sites in Tennessee 26-5
26-2 Comparison of Measured Concentrations and EPA Screening Values for the Tennessee
Monitoring Sites 26-6
26-3 Daily and Seasonal Averages for the Pollutants of Interest for the Tennessee
Monitoring Sites 26-8
xxxv
-------
LIST OF TABLES (Continued)
Page
26-4 Non-Chronic Risk Summary for the Tennessee Monitoring Sites 26-10
26-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Tennessee Monitoring Sites 26-14
26-6 Motor Vehicle Information for the Tennessee Monitoring Sites 26-21
26-7 Chronic Risk Summary for the Monitoring Sites in Tennessee 26-25
26-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in Tennessee 26-27
26-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in Tennessee 26-28
27-1 Average Meteorological Conditions near the Monitoring Sites in Texas 27-11
27-2 Comparison of Measured Concentrations and EPA Screening Values for the Texas
Monitoring Sites 27-13
27-3 Daily and Seasonal Averages for the Pollutants of Interest for the Texas Monitoring
Sites 27-17
27-4 Non-Chronic Risk Summary for the Texas Monitoring Sites 27-21
27-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Texas Monitoring Sites 27-30
27-6 Motor Vehicle Information for the Texas Monitoring Sites 27-47
27-7 Chronic Risk Summary for the Monitoring Sites in Texas 27-50
27-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Monitoring Sites in Texas 27-56
27-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Monitoring Sites in Texas 27-59
28-1 Average Meteorological Conditions near the Monitoring Site in Utah 28-4
28-2 Comparison of Measured Concentrations and EPA Screening Values for the Utah
Monitoring Site 28-5
28-3 Daily and Seasonal Averages for the Pollutants of Interest for the Utah Monitoring
Site 28-7
28-4 Non-Chronic Risk Summary for the Utah Monitoring Site 28-9
28-5 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Utah Monitoring Site 28-12
28-6 Motor Vehicle Information for the Utah Monitoring Site 28-16
28-7 Chronic Risk Summary for the Monitoring Site in Utah 28-20
28-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for BTUT 28-23
28-9 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for BTUT 28-24
29-1 Average Meteorological Conditions near the Monitoring Site in Vermont 29-4
29-2 Comparison of Measured Concentrations and EPA Screening Values for the Vermont
Monitoring Site 29-5
29-3 Daily and Seasonal Averages for the Pollutants of Interest for the Vermont Monitoring
Site 29-6
xxxvi
-------
LIST OF TABLES (Continued)
Page
29-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Vermont Monitoring Site 29-8
29-5 Motor Vehicle Information for the Vermont Monitoring Site 29-13
29-6 Chronic Risk Summary for the Monitoring Site in Vermont 29-14
29-7 Top 10 Emissions, Toxi city-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for UNVT 29-16
29-8 Top 10 Emissions, Toxi city-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for UNVT 29-17
30-1 Average Meteorological Conditions near the Monitoring Site in Washington 30-4
30-2 Comparison of Measured Concentrations and EPA Screening Values for the Washington
Monitoring Site 30-5
30-3 Daily and Seasonal Averages for the Pollutants of Interest for the Washington
Monitoring Site 30-6
30-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Washington Monitoring Site 30-8
30-5 Motor Vehicle Information for the Washington Monitoring Site 30-13
30-6 Chronic Risk Summary for the Monitoring Site in Washington 30-14
30-7 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for SEW A 30-16
30-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for SEW A 30-17
31-1 Average Meteorological Conditions near the Monitoring Sites in Wisconsin 31-6
31-2 Comparison of Measured Concentrations and EPA Screening Values for the Wisconsin
Monitoring Sites 31-8
31-3 Daily and Seasonal Averages for the Pollutants of Interest for the Wisconsin
Monitoring Sites 31-9
31-4 Pollutants of Interest Concentration Correlations with Selected Meteorological
Parameters for the Wisconsin Monitoring Sites 31-12
31-5 Motor Vehicle Information for the Wisconsin Monitoring Sites 31-19
31-6 Chronic Risk Summary for the Monitoring Sites in Wisconsin 31-22
31-7 Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for the Wisconsin Monitoring Sites 31-25
31-8 Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants
with Noncancer RfCs for the Wisconsin Monitoring Sites 31-26
32-1 Average Precision by Method 32-4
32-2 VOC Sampling and Analytical Precision: 228 Duplicate and Collocated Samples 32-4
32-3 VOC Sampling and Analytical Precision: 80 Collocated Samples 32-6
32-4 VOC Sampling and Analytical Precision: 148 Duplicate Samples 32-8
32-5 VOC Sampling and Analytical Precision: 12 Duplicate Samples for
Bountiful, UT (BTUT) 32-9
32-6 VOC Sampling and Analytical Precision: 10 Collocated Samples for
Detroit, MI (DEMI) 32-11
xxxvii
-------
LIST OF TABLES (Continued)
Page
32-7 VOC Sampling and Analytical Precision: 12 Duplicate Samples for
Grand Junction, CO (GPCO) 32-13
32-8 VOC Sampling and Analytical Precision: 12 Collocated Samples for
Northbrook, IL (NBIL) 32-14
32-9 VOC Sampling and Analytical Precision: 10 Duplicate Samples for
St. Louis, MO (S4MO) 32-16
32-10 VOC Sampling and Analytical Precision: Coefficient of Variation for all Duplicate and
Collocated Samples by Site 32-18
32-11 SNMOC Sampling and Analytical Precision: 64 Duplicate and Collocated
Samples 32-24
32-12 SNMOC Sampling and Analytical Precision: 52 Duplicate Samples 32-26
32-13 SNMOC Sampling and Analytical Precision: 12 Duplicate Samples for
Bountiful, UT (BTUT) 32-28
32-14 SNMOC Sampling and Analytical Precision: 12 Collocated Samples for
Northbrook, IL (NBIL) 32-29
32-15 SNMOC Sampling and Analytical Precision: Coefficient of Variation for all
Duplicate and Collocated Analyses by Site 32-32
32-16 Carbonyl Sampling and Analytical Precision: 316 Duplicate and
Collocated Samples 32-34
32-17 Carbonyl Sampling and Analytical Precision: 82 Collocated Samples 32-34
32-18 Carbonyl Sampling and Analytical Precision: 234 Duplicate Samples 32-35
32-19 Carbonyl Sampling and Analytical Precision: 12 Duplicate Samples for
Bountiful, UT (BTUT) 32-36
32-20 Carbonyl Sampling and Analytical Precision: 8 Collocated Samples for
Detroit, MI (DEMI) 32-36
32-21 Carbonyl Sampling and Analytical Precision: 10 Duplicate Samples for
Grand Junction, CO (GPCO) 32-37
32-22 Carbonyl Sampling and Analytical Precision: 16 Collocated Samples for
Northbrook, IL (NBIL) 32-37
32-23 Carbonyl Sampling and Analytical Precision: 14 Duplicate Samples for
St. Louis, MO (S4MO) 32-38
32-24 Carbonyl Sampling and Analytical Precision: 12 Duplicate Samples for
Tampa, FL (SKFL) 32-39
32-25 Carbonyl Sampling and Analytical Precision: 14 Duplicate Samples for
Tampa, FL (SYFL) 32-39
32-26 Carbonyl Sampling and Analytical Precision: Coefficient of Variation for all
Duplicate and Collocated Analyses by Site 32-40
32-27 PMio Metal Sampling and Analytical Precision: 84 Collocated Samples 32-42
32-28 PMio Metal Sampling and Analytical Precision: 54 Collocated Samples at
Boston, MA (BOMA) 32-42
32-29 PMio Metal Sampling and Analytical Precision: 4 Collocated Samples at
Bountiful, UT (BTUT) 32-43
32-30 PMio Metal Sampling and Analytical Precision: 26 Collocated Samples at
St. Louis, MO (S4MO) 32-43
XXXVlll
-------
LIST OF TABLES (Continued)
Page
32-31 Metals Sampling and Analytical Precision: Coefficient of Variation for all Collocated
Samples by Site 32-44
32-32 Hexavalent Chromium Sampling and Analytical Precision: Collocated Samples 32-45
32-33 VOC Analytical Precision: 476 Replicate Analyses for all Duplicate and Collocated
Samples 32-46
32-34 VOC Analytical Precision: 182 Replicate Analyses for all Collocated Samples 32-48
32-35 VOC Analytical Precision: 294 Replicate Analyses for all Collocated Samples 32-49
32-36 VOC Analytical Precision: 24 Replicate Analyses for Duplicate Samples for
Bountiful, UT (BTUT) 32-51
32-37 VOC Analytical Precision: 32 Replicate Analyses for Collocated Samples for
Detroit, MI (DEMI) 32-53
32-38 VOC Analytical Precision: 24 Replicate Analyses for Duplicate Samples for Grand
Junction, CO (GPCO) 32-54
32-39 VOC Analytical Precision: 24 Replicate Analyses for Collocated Samples for
Northbrook, IL (NBIL) 32-56
32-40 VOC Analytical Precision: 22 Replicate Analyses for Duplicate Samples for
St. Louis, MO (S4MO) 32-58
32-41 VOC Analytical Precision: Coefficient of Variation for all Replicate Analyses
by Site 32-60
32-42 SNMOC Analytical Precision: 128 Replicate Analyses for all Duplicate and
Collocated Samples 32-65
32-43 SNMOC Analytical Precision: 104 Replicate Analyses for all Duplicate Samples 32-67
32-44 SNMOC Analytical Precision: 56 Replicate Analyses for Duplicate Samples for
Bountiful, UT (BTUT) 32-69
32-45 SNMOC Analytical Precision: 24 Replicate Analyses for Collocated Samples for
Northbrook, IL (NBIL) 32-71
32-46 SNMOC Analytical Precision: Coefficient of Variation for all Replicate Analyses,
All Sites 32-74
32-47 Carbonyl Analytical Precision: 734 Replicate Analyses for all Duplicate and
Collocated Samples 32-76
32-48 Carbonyl Analytical Precision: 246 Replicate Analyses for all Collocated Samples... 32-77
32-49 Carbonyl Analytical Precision: 470 Replicate Analyses for all Duplicate Samples .... 32-77
32-50 Carbonyl Analytical Precision: 24 Replicate Analyses for Duplicate Samples for
Bountiful, UT (BTUT) 32-78
32-51 Carbonyl Analytical Precision: 110 Replicate Analyses for Collocated Samples for
Detroit, MI (DEMI) 32-79
32-52 Carbonyl Analytical Precision: 20 Replicate Analyses for Duplicate Samples for
Grand Junction, CO (GPCO) 32-79
32-53 Carbonyl Analytical Precision: 32 Replicate Analyses for Duplicate Samples for
Northbrook, IL (NBIL) 32-80
32-54 Carbonyl Analytical Precision: 28 Replicate Analyses for Duplicate Samples for
St. Louis, MO (S4MO) 32-80
32-55 Carbonyl Analytical Precision: 24 Replicate Samples for Duplicate Samples for
Tampa, FL (SKFL) 32-81
XXXIX
-------
LIST OF TABLES (Continued)
Page
32-56 Carbonyl Analytical Precision: 28 Replicate Samples for Duplicate Samples for
Tampa, FL (SYFL) 32-81
32-57 Carbonyl Analytical Precision: Coefficient of Variation for all Replicate Analyses
by Site 32-82
32-58 Hexavalent Chromium Analytical Precision: Replicate Analyses for Collocated
Samples 32-84
32-59 Carbonyl NATTS PT Audit Samples - Percent Difference from True Value 32-86
32-60 Metals NATTS PT Audit Samples - Percent Difference from True Value 32-86
32-61 VOC NATTS PT Audit Samples - Percent Difference from True Value 32-86
xl
-------
LIST OF ACRONYMS
AGL Above ground level
AIRS Aerometric Information and Retrieval System
AQS Air Quality Subsystem (of the Aerometric Information and Retrieval System)
ATSDR Agency for Toxic Substances and Disease Registry
BTEX benzene, toluene, ethylbenzene, and xylenes (o-, m-, and/>-xylene)
CALEPA California EPA
CBS A Core-based statistical area(s)
CFR Code of Federal Regulations
CV coeffi ci ent of vari ati on
DNPH 2,4-dinitrophenylhydrazine
DQO Data Quality Objective(s)
EPA U.S. Environmental Protection Agency
ERG Eastern Research Group
GC gas chromatography
GC/MS-FID gas chromatography/mass spectrometry and flame ionization detection
HAP hazardous air pollutant
HPLC high-performance liquid chromatography
HQ Hazard Quotient
HYSPLIT Hybrid Single-Particle Lagrangian Integrated Trajectory
1C Ion Chromatography
L liter
m3 Cubic meter
MDL method detection limit
MRL Minimal risk level
MSA metropolitan statistical area(s)
MTBE methyl tert-butyl ether
NATA National Air Toxics Assessment
NATTS National Air Toxics Trends Site
NA not applicable
ND Non-detect
NEI National Emissions Inventory
ng/m3 Nanograms per cubic meter
NOAA National Oceanic and Atmospheric Administration
ppbC parts per billion carbon
ppbv parts per billion (by volume)
pg/m3 Picograms per cubic meter
PM particulate matter
PUF Polyurethane foam
QAPP Quality Assurance Project Plan
xli
-------
LIST OF ACRONYMS (Continued)
REL Reference exposure limit
RfC Reference Concentration
RFG Reformulated gasoline
RPD relative percent difference
SIP State Implementation Plan(s)
SNMOC Speciated Nonmethane Organic Compound
SVOC Semivolatile Organic Compounds
UATMP Urban Air Toxics Monitoring Program
VOC Volatile Organic Compound(s)
TAD Technical Assistance Document
TNMOC Total Nonmethane Organic Compound(s)
tpy tons per year
TSP Total Suspended Particulate
|ig/m3 Micrograms per cubic meter
URE Unit Risk Estimate
WBAN Weather Bureau/Army/Navy ID
xlii
-------
Abstract
This report presents the results and conclusions from the ambient air monitoring conducted
as part of the 2006 Urban Air Toxics Monitoring Program (UATMP)—a program designed to
characterize the magnitude and composition of potentially toxic air pollution in, or near, urban
locations. The 2006 UATMP included 59 monitoring sites that collected 24-hour air samples,
typically on a 6- or 12-day schedule. Forty-five sites sampled for 60 volatile organic compounds
(VOC) and/or 15 carbonyl compounds. Five sites sampled for 80 speciated nonmethane organic
compounds (SNMOC) and an additional five sites sampled for total NMOC (TNMOC). Six sites
sampled for semivolatile compounds (SVOC). Twenty sites sampled for 11 metals and 23 sites
sampled for hexavalent chromium. Overall, over 180,000 ambient air concentrations were
measured during the 2006 UATMP. This report uses various graphical, numerical, and statistical
analyses to put the vast amount of ambient air monitoring data collected into perspective. Not
surprisingly, the ambient air concentrations measured during the program varied significantly
from city to city and from season to season.
The ambient air monitoring data collected during the 2006 UATMP serve a wide range of
purposes. Not only do these data characterize the nature and extent of urban air pollution close to
the 59 monitoring sites participating in this study, but they also indicate some trends and patterns
that may be common to all urban environments. Therefore, this report presents some results that
are specific to particular monitoring locations and presents other results that are apparently
common to urban environments. The results should ultimately provide additional insight into the
complex nature of urban air pollution. The final data are also included in the appendices to this
report.
xliii
-------
1.0 Introduction
Air pollution in urban locations incorporates many components that originate from a
wide range of stationary, mobile, area, and natural emissions sources. Because some of these
components include toxic compounds known or suspected to have the potential for negative
human health impacts, the U.S. Environmental Protection Agency (EPA) continues to encourage
state, local, and tribal agencies to understand and appreciate the nature and extent of toxic air
pollution in urban locations. To achieve this goal, EPA sponsors the Urban Air Toxics
Monitoring Program (UATMP) to characterize the composition and magnitude of urban air
pollution through extensive ambient air monitoring. Since the inception of the UATMP in 1987,
many environmental and health agencies have participated in the program to assess the sources
and effects of air pollution within their jurisdictions. This report summarizes and interprets the
2006 UATMP monitoring effort, which includes up to twelve months of l-in-6 and l-in-12 day
measurements of ambient air quality at 59 monitoring sites in or near 38 urban/rural locations in
28 states, including 29 metropolitan statistical areas (MSA). Much of the data analyses and
interpretation in this report focuses on pollutant-specific risk potential.
The contents of this report provide both a qualitative overview of air toxics pollution at
selected urban and rural locations and a quantitative analysis of the factors that appear to affect
urban and rural air quality most significantly. This report also focuses on data characterization
at each of the 59 different air sampling locations, a site-specific approach that allows for much
more detailed analyses of the factors (e.g., stationary sources, mobile sources, natural sources,
meteorological influences) that affect air quality differently from one location to the next. While
the analyses presented in this report are extensive, they are by no means comprehensive. Each
state section highlights the more definitive results and trends; however, a more detailed look at
the results provides further insight.
The contents of this report offer participating agencies useful insights into important air
quality issues. For example, participating agencies can use trends and patterns in the UATMP
monitoring data to determine whether levels of air pollution present public health concerns, to
identify which emission sources contribute most to air pollution, or to forecast whether proposed
pollution control initiatives might significantly improve air quality. Since 2001, EPA has been
1-1
-------
actively conducting the National Air Toxics Assessment (NATA), which uses air toxics
emissions data to model ambient monitoring concentrations across the nation. UATMP
monitoring data may be used to compare modeling results, such as NATA. Policy-relevant
questions that the UATMP may help answer include the following:
• Which anthropogenic sources substantially degrade air quality?
• Have pollutant concentrations decreased as a result of regulations?
• Which pollutants contribute the greatest health risk on a short-term, intermediate-
term, and long-term basis?
The data analyses in this report are applied at every participating UATMP monitoring
site, depending upon pollutants sampled for, and present a comprehensive account of urban air
pollution. However, state and local environmental agencies are encouraged to perform
additional analyses on the monitoring data so that the many factors that affect their specific
ambient air quality can be understood fully. While each state section is designed to be a stand-
alone section to allow those interested in a particular site or state to understand the analyses
without having to read the entire report, it is recommended that Sections 1 through 3 and 32 be
read as complements to the state sections.
To facilitate examination of the 2006 UATMP monitoring data, the complete set of
measured concentrations is presented in the appendices of this report. In addition, these data are
publicly available in electronic format from the Air Quality Subsystem (AQS) of EPA's
Aerometric Information Retrieval System (AIRS) at http://www.epa.gov/ttn/airs/airsaqs/.
The report is organized into 34 sections and 12 appendices. Table 1-1 highlights the
contents of each section.
1-2
-------
Table 1-1. Organization of the 2006 UATMP Report
Report
Section
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Section Title
Introduction
The 2006 UATMP
Summary of the 2006 UATMP
Sites in Alabama
Site in Arizona
Site in Colorado
Site in Washington, B.C.
Sites in Florida
Site in Georgia
Sites in Illinois
Sites in Indiana
Site in Kentucky
Site in Massachusetts
Sites in Michigan
Site in Minnesota
Overview of Contents
Introduction to the background and scope of the
UATMP.
This section provides background information on the
scope of the 2006 UATMP and includes information
about the following:
• Monitoring locations
• Pollutants selected for monitoring
• Sampling and analytical methods
• Sampling schedules
• Completeness of the air monitoring program.
This section, which presents and discusses significant
trends and relationships in the UATMP data,
characterizes how ambient air concentrations varied
with monitoring location and with time, presents an
interpretation of the significance of the observed
spatial and temporal variations, and evaluates risk.
Monitoring results for Birmingham-Hoover, AL MSA
(ETAL, NBAL, PVAL, and SIAL)
Monitoring results for Phoenix-Mesa-Scottsdale, AZ
MSA (PXSS)
Monitoring results for Grand Junction, CO MSA
(GPCO)
Monitoring results for Washington, DC MSA (WADC)
Monitoring results for Orlando-Kissimmee, FL MSA
(ORFL), Miami-Ft. Lauderdale-Pompano Beach, FL
MSA (FLFL), and Tampa-St. Petersburg-Clearwater,
FL MSA (AZFL, GAFL, SKFL, SMFL, and SYFL)
Monitoring results for Atlanta-Sandy Springs-Marietta,
GA MSA (SDGA)
Monitoring results for Chicago-Naperville-Joliet, IL-
IN-WI MSA (NBIL and SPIL)
Monitoring results for Chicago-Naperville-Joliet, IL-
IN-WI MSA (INDEM), and Indianapolis-Carmel, IN
MSA (IDIN, ININ, and WPIN)
Monitoring results for Hazard, KY (HAKY)
Monitoring results for Boston-Cambridge-Quincy,
MA-NH MSA (BOMA)
Monitoring results for Detroit-Warren-Livonia, MI
MSA (DEMI) and Sault Sainte Marie, MI (ITCMI)
Monitoring results for Minneapolis-St.Paul-
Bloomington, MN MSA (MIMN)
1-3
-------
Table 1-1. Organization of the 2006 UATMP Report (Continued)
Report
Section
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Section Title
Sites in Mississippi
Site in Missouri
Sites in New Jersey
Sites in North Carolina
Sites in Oklahoma
Site in Oregon
Sites in Puerto Rico
Site in Rhode Island
Site in South Carolina
Sites in South Dakota
Sites in Tennessee
Sites in Texas
Site in Utah
Site in Vermont
Site in Washington
Sites in Wisconsin
Data Quality
Overview of Contents
Monitoring results for Tupelo, MS (TUMS) and Post-
Katrina monitoring results for Gulfport-Biloxi, MS
MSA (GPMS)
Monitoring results for St. Louis, MO-IL MSA (S4MO)
Monitoring results for New York-Northern New
Jersey-Long Island, NY-NJ-PA MSA (CHNJ, ELNJ,
and NBNJ) and Philadelphia-Camden-Wilmington,
PA-NJ-DE-ND MSA (CANJ)
Monitoring results for Durham, NC MSA (RTPNC)
and Candor, NC (CANC)
Monitoring results for Tulsa, OK MSA (TOOK,
TSOK, and TUOK) and Pryor, OK (CNEP)
Monitoring results for La Grande, OR (LAOR)
Monitoring results for San Juan-Caguas-Guaynabo, PR
MSA (BAPR and SJPR)
Monitoring results for Providence -New Bedford-Fall
River, RI-MA MSA (PRRI)
Monitoring results for Chesterfield, SC (CHSC)
Monitoring results for Custer, SD (CUSD) and Sioux
Falls, SD MSA (SFSD)
Monitoring results for Knoxville, TN MSA (LDTN
and MSTN)
Monitoring results for Austin-Round Rock, TX MSA
(MUTX, PITX, RRTX, TRTX, and WETX) and El
Paso, TX MSA (YDSP)
Monitoring results for Ogden-Clearfield, UT MSA
(BTUT)
Monitoring results for Burlington-South Burlington,
VT MSA (UNVT)
Monitoring results for Seattle-Tacoma-Bellevue, WA
MSA (SEWA)
Monitoring results for Madison, WI MSA (MAWI)
and Mayville, WI (MVWI)
This section defines and discusses the concepts of
precision and accuracy. Based on quantitative and
qualitative analyses, this section comments on the
precision and accuracy of the 2006 UATMP ambient
air monitoring data.
1-4
-------
Table 1-1. Organization of the 2006 UATMP Report (Continued)
Report
Section
33
34
Section Title
Conclusions and Recommendations
References
Overview of Contents
This section summarizes the most significant findings
of the report and makes several recommendations for
future projects that involve ambient air monitoring in
urban locations.
This section lists the references cited throughout the
report.
1-5
-------
2.0 The 2006 UATMP
The 2006 UATMP included 59 monitoring sites that collected 24-hour integrated
ambient air samples for up to 12 months, at l-in-6 or l-in-12 day sampling intervals. Section 2.5
provides further details on each of the sampling methodologies used to collect samples. All
UATMP samples were analyzed in the Eastern Research Group (ERG) laboratory in Morrisville,
NC. Samples were analyzed for concentrations of selected hydrocarbons, halogenated
hydrocarbons, and polar compounds from canister samples (TO-15 and SNMOC), carbonyl
compounds from sorbent cartridge samples (TO-11A), semivolatile organic compounds (SVOC)
from polyurethane foam (PUF) samples (TO-13) or XAD-2 resin samples (SW846 Method
8270), hexavalent chromium from the EPA-approved method, and trace metals from filters
(IO-3.5). The following discussion reviews the monitoring locations, pollutants selected for
monitoring, collection schedules, sampling and analytical methods, and completeness of the
2006 UATMP dataset.
2.1 Monitoring Locations
Although EPA sponsors the UATMP, EPA does not dictate the location of its monitoring
sites. Rather, representatives from the state, local, and tribal agencies that voluntarily participate
in the program and contribute to the overall monitoring costs select the monitoring locations
based on specific siting criteria and study needs. Some monitors were placed in urban areas near
the centers of heavily populated cities (e.g., Chicago, IL and Phoenix, AZ), while others were
placed in moderately populated rural areas (e.g., Candor, NC and Custer, SD).
In the wake of Hurricane Katrina's devastation to the Gulf Coast in late August 2005,
EPA, state, and local agencies in Mississippi and Louisiana developed and implemented an
intensive sampling initiative to evaluate air, water, and sediment quality during the clean-up and
recovery process. To evaluate air quality, a network of nearly 30 ambient monitoring sites was
instituted in Louisiana and Mississippi. One of those sites sampled year-round in 2006. At the
request of the State of Mississippi, part of the post-Katrina data from the Gulfport, MS site are
included in this report. The site serving as the background site for post-Katrina data analysis
(Tupelo, MS) is also a UATMP site, and its results are also presented in this report.
2-1
-------
Figure 2-1 shows the locations of the 59 monitoring sites, which encompass 38 different
urban and rural areas, participating in the 2006 program. Outlined in Figure 2-1 are the
associated core-based statistical areas (CBSA), as designated by the U.S. Census Bureau, where
each site is located. A CBSA refers to either a micropolitan or metropolitan statistical area (US
Census Bureau, 2007). The site-specific descriptions in Tables 2-1 and 2-2 and in Appendix A
provide detailed information on the surroundings near the 2006 UATMP monitoring locations.
Monitoring sites that are designated as part of EPA's National Air Toxic Trend Station (NATTS)
network are indicated by bold type in Table 2-1. The NATTS network, consisting of
23 monitoring sites located in different geographical areas with varying population densities,
was designed to "provide long-term monitoring data for certain priority air toxics across
representative areas of the country in order to establish overall trends for these pollutants" (EPA,
2005a).
Eight new sites participated in the 2006 UATMP program. The 51 monitoring sites
participating in previous UATMP are listed in Table 2-3. These 51 sites are discussed further in
Section 3.3.4, Site Trends Analysis, and the individual state sections. Sections 4 through 31 are
state-specific breakdowns of the data analysis, and contain topographic maps for each of the
sites. Stationary source facilities within 10 miles of the monitoring sites are provided in these
sections as well. The location and category descriptions of these emissions sources were
retrieved from the 2002 National Emission Inventory (NET) (EPA, 2006a).
As Figure 2-1 shows, the 2006 UATMP monitoring sites are widely distributed across the
country. The monitoring data from these sites may indicate certain air quality trends that are
common to all urban environments, but may also show distinct geographic trends. The data
analyses in this report differentiate those trends that appear to be site-specific from those that
appear to be common to most urban environments.
2-2
-------
Figure 2-1. Monitoring Site Locations for the 2006 UATMP
to
oo
Sault Sainte Marie, Ml
Minneapolis,'MN
Boston, MA
»
Providence, Rl
Detroit, Ml
Chester, NJ
Camden, NJ /
T-, 1
(J • [ Indianapolis,
Schiller Park, IL
Northbrook
Elizabeth, NJ
New Brunswick, NJ
Grand Junction, CO
St. Louis, MO
Cherokee Heights, .OK
~
•Candor, NC
Chesterfield, SC
Birmingham, AL
Round Rock, TX
^
Austin'TX
Winter Park, FL
Plant City,
Pinellas Park, FL
Tampa,
St. Petersburg, F
Legend
Monitoring site
Metropolitan/Micropolitan Statistical Area
Barceloneta, PR
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites
Site Code
AZFL
BAPR
BOMA
Location
Azalea Park, St.
Petersburg, FL
Barceloneta, PR
Boston, MA
Land Use
Residential
Residential
Commercial
Location
Setting
Suburban
Rural
Urban
Estimated
Traffic
(# vehicles)
51,000
10
27,287
Traffic
Year
Estimate
Unknown
1994
2000
Description of the
Immediate Surroundings
A neighborhood spatial scale of representativeness
characterizes this monitoring site selected for the Tampa Bay
pilot project. This monitor is sited in an area of high
population density with uniform mixed land use, consisting of
residential, commercial, and industrial properties. Major point
sources are located approximately 2 to 10 miles from the
monitoring site. In addition, this site is at least 150 meters
from major roadways. However, given the proximity of motor
vehicle traffic it is expected that mobile sources will
contribute appreciably to the measured samples.
The Barceloneta site is a residential area surrounded by 5
pharmaceutical plants. The greater area outside the city is
rural in character and the city itself is within 2 miles of the
Atlantic Ocean.
The Boston site is located in a residential neighborhood on
Harrison Avenue in Dudley Square. Its purpose is to measure
population exposure for a city bus terminal which is located
across the street from the monitor and other urban sources.
to
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
BTUT
CANC
CANJ
CHNJ
Location
Bountiful, UT
Candor, NC
Camden, NJ
Chester, NJ
Land Use
Residential
Forest
Residential
Agricultural
Location
Setting
Suburban
Rural
Suburban
Rural
Estimated
Traffic
(# vehicles)
33,310
100
62,000
12,623
Traffic
Year
Estimate
2002
1999
1986
1995
Description of the
Immediate Surroundings
The Bountiful Viewmont site is located in a suburban area of
the Ogden-Clearfield MSA, at 171 West 1370 North in
Bountiful, Utah. This site is a relocation of the BOUT site,
which was about 1.1 miles south of the new site. The site is
located on the grounds of Viewmont High School, adjacent to
a parking lot, tennis courts, and a football field. The
surrounding neighborhood is made up of residential
properties. BTUT is a SLAMS neighborhood-scale site for
monitoring population exposure to SO2, CO, NO2, and PM2 5;
and a NAMS neighborhood-scale site for monitoring
maximum ozone concentrations. Speciated PM2 5 sampling,
meteorological monitoring, and NATTS air toxics sampling
are also done at the Bountiful Viewmont site. Several
petroleum refineries are located two to five miles away from
the site, as are several sand and gravel mining operations.
The Candor, NC, site is in rural Montgomery Co., at the end
of a private dead end road named Perry Dr. The site sits
approximately 1.5 miles off a main road (McCallum Road.).
There is not a pollution source within 5 miles of the site. EPA
also monitors next to this site.
Although this monitoring site in Camden, NJ, is in a
residential area, numerous industrial facilities and busy
roadways are located within a 10 mile radius. The monitors
are situated in a parking lot of a business complex.
The Chester, NJ, site is located in a rural-agricultural,
residential section and is topographically rolling. The site is
located near Lucent Laboratory Building #1. There is
potential population exposure to ozone, NO2, and SO2.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
Location
Land Use
Location
Setting
Estimated
Traffic
(# vehicles)
Traffic
Year
Estimate
Description of the
Immediate Surroundings
CHSC
Chesterfield, SC
Forest
Rural
550
2000
The site was chosen as a background site. It is very rural and
in the middle of Carolina Sandhills Wildlife Refuge. The site
is located on secondary road SC 145 between McBee and
Chesterfield. Traffic on 145 is light. The nearest industry
(AO Smith Water Heaters) is approximately 9 miles away.
Elevation is -450'.
to
CNEP
Pryor, OK
Agricultural
Rural
2003
The Cherokee Nation's Environmental Program (CNEP)
established this ambient air monitoring site on tribal trust land
at the Cherokee Heights community in 2004. The purpose of
this sampling project is to obtain additional data about the
concentrations of VOCs in ambient air at the Pryor site and in
the adjacent Cherokee Heights tribal community. This site is
approximately 3.8 miles from the coal-fired power plant,
1.5 miles from the gas-fired power plant, and 0.75 mile from
the sewage lagoon of the industrial park. Current
instrumentation at the site includes the following: R & P
TEOM for continuous PM10 measurement (Federal
Equivalent Method), R & P TEOM with FDMS for
continuous PM2 5 measurement (the FDMS includes reference
flow to account for volatile loss), R & P 2025 sequential
sampler for PM2 5 (Federal Reference Method), API gaseous
monitors for NOX, NOy, ozone, and SO2, and MetOne
meteorological instruments for wind speed, wind direction,
ambient temperature, and relative humidity.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
Location
Land Use
Location
Setting
Estimated
Traffic
(# vehicles)
Traffic
Year
Estimate
Description of the
Immediate Surroundings
CUSD
Custer, SD
Residential
Suburban
1,940
2002
The site is located on the edge of an urban area, in a pasture
across the road from the last housing development on the east
side of the City of Custer. The city has a population of 1,860
and is the largest city in the county. The city is located in a
river valley in the Black Hills with pine covered hills on the
north and south sides of the valley. The site is located in the
center of the valley on the east side of the city. Major sources
near the site include vehicles (highest traffic counts from May
through September), forest fires (mainly during July through
September), wood burning for heat, and wildland heath fires
(during the winter months). The main industries in the area
include tourism, logging, and mining of feldspar/quartz.
to
DEMI
Dearborn, MI
Industrial
Suburban
12,791
1990
The Dearborn, MI site is located in a residential neighborhood
with industrial impacts. An auto and steel manufacturing
plant is located in close proximity to the monitoring site.
Previous violations of the PM10 standard have also occurred at
this site. The site lies between 1-75 and 1-94. This site is
expected to show some of the highest levels of air toxics in
the Detroit Pilot program area. The SO2 and PM10
measurements are also made there.
ELNJ
Elizabeth, NJ
Industrial
Suburban
170,000
Unknown
The Elizabeth site is located in Union County, NJ, at an
urban-industrial site where the topography is relatively
smooth. The monitoring site is located 75 yards away from the
Toll Plaza and about one mile from Bayway Refinery. The
neighborhood scale is at maximum concentration. The
location has a PM10 filter analyzer for sulfates and nitrates as
well as the UATMP site.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
Location
Land Use
Location
Setting
Estimated
Traffic
(# vehicles)
Traffic
Year
Estimate
Description of the
Immediate Surroundings
ETAL
East Thomas,
Birmingham, AL
Residential
Suburban
30,000
Unknown
This SLAMS microscale roadway site (located at the
intersection of Finley Avenue and Arkadelphia Road) has a
thirty-five year history of ambient air monitoring. This site is
used mainly to monitor vehicle emissions. It is also an
environmental justice site in that most of the residences in the
area are owned and occupied by minorities. It is also located
in a valley that is heavily industrialized. This site has also
yielded some of the county's highest reported paniculate
levels. There have been several special roadway emission
studies performed at this site over the past few years, the latest
of which was pertaining to the contribution of PM25 particles
from roadway emissions.
to
i
oo
FLFL
Davie, FL
Commercial
Suburban
8000
Unknown
The site is located on the campus of the University of Florida,
Agricultural Research Center in Davie, Florida. It is located
in a generally residential area that is surrounded by 4 major
thoroughfares in the county (~1 mile from 1-595, ~2 miles
from the Florida Turnpike, ~6 miles from 1-95, and ~6 miles
from 1-75). It is located ~ 6 miles from the Ft. Lauderdale-
Hollywood International Airport and ~9 miles from Port
Everglades. It is in an area generally representative of the
ambient air conditions experienced throughout the county. It
is expected that this site will become an NCORE type II site
in the near future.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
Location
Land Use
Location
Setting
Estimated
Traffic
(# vehicles)
Traffic
Year
Estimate
Description of the
Immediate Surroundings
GAFL
Gandy, Tampa, FL
Commercial
Suburban
81,460
Unknown
to
A neighborhood spatial scale of representativeness
characterizes this monitoring site selected for the Tampa Bay
Region Air Toxics Study Monitoring Stations (TBRATS)
pilot project. This monitor is sited in an area of high
population density with uniform mixed land use, consisting of
residential, commercial, and industrial properties. Major point
sources are located greater than one mile from the monitoring
site. Since the emission points from these sources are
elevated and not proximate to the monitor, concentrations
measured during this study should not be dominated by a
single source. In addition, this site is at least 150 meters from
major roadways. However, given the proximity of motor
vehicle traffic, mobile sources are expected to contribute
appreciably to the measured samples.
GPCO
Grand Junction, CO
Commercial
Urban
19,572
2000-2002
This site is a small 1-story shelter that houses the
VOC/carbonyl sampler. The inlet for this sampler is 13' above
the ground and 35' south of Pitkin Avenue. This site also has
meteorological sensors (WS, WD, T, RH) on a 10 meter
tower, a carbon monoxide sampler and a continuous PMio
sampler. Monitoring is being conducted on the southeast side
of the downtown area. The area is very mixed usage, with
commercial business to the west, northwest and north,
residential to the northeast and east, and industrial to the
southeast, south and southwest. The location is next to one of
the major east-west roads in Grand Junction.
GPMS
Gulfport, MS
Commercial
Rural
17,000
1995
The Gulfport site is in a light commercial and residential area.
This site was selected because this area is believed to have
high ambient air toxic concentrations based upon information
from the NATA study and Mississippi's major source
emission inventories.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
Location
Land Use
Location
Setting
Estimated
Traffic
(# vehicles)
Traffic
Year
Estimate
Description of the
Immediate Surroundings
HAKY
Hazard, KY
Residential
Suburban
500
1999
The Perry County Horse Park monitoring station was
established in April 2000 and is designated as a SLAMS site
for PM10 and a Special Purpose Monitoring site for ozone and
PM2 5. In October 2001, PM25 Speciation sampling was
added as part of the national speciation program. The site is
located on the grounds of the Perry County Horse Park and is
approximately 2.5 miles north/northeast of Hazard. The
monitoring station is an 8' x 10' aluminum clad shelter with a
wooden deck covering the roof. The closest structure to the
site is Perry Central High School, which is about 600 feet
northwest of the site. The elevation is at 912 feet.
to
i
o
IDIN
Stout Field in
Indianapolis, IN
Military
Reservation
Urban
30,916
1996
This site is located at Stout Field National Guard Armory.
This monitor is strategically located based on an evaluation of
U.S. EPA's 1996 and 1999 NATA; its proximity to major
sources for HAP emissions; its proximity to areas where the
public lives and congregates; and its history of housing
operating monitors. This site monitors for metals, carbonyls,
and VOC.
INDEM
Gary, IN
Industrial
Urban
42,950
1990
This site is located on property now owned by the Dunes
National Lakeshore. It is approximately one-half to three-
quarters of a mile south west of the USX coking battery for
their mill. The site is part of the Chicago PAMS network. It
is considered a Type 2 or source site. Monitoring for ozone,
NO/NOX, ozone precursors, and carbonyls began in 1995 as
the network was deployed in Wisconsin, Illinois, Indiana, and
Michigan. Other parameters monitored at this location are
SO2, PMio, PM25, speciated PM25, and several meteorological
parameters.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
Location
Land Use
Location
Setting
Estimated
Traffic
(# vehicles)
Traffic
Year
Estimate
Description of the
Immediate Surroundings
ININ
South Harding St.,
Indianapolis, IN
Residential
Urban
97,780
2002
This site is located on South Harding Street. This monitor is
strategically located based on an evaluation of U.S. EPA's
1996 and 1999 NATA; its proximity to major sources for
HAP emissions; its proximity to areas where the public lives
and congregates; and its history of housing operating
monitors. This site monitors for metals, carbonyls, VOC, and
hexavalent chromium.
ITCMI
Sault Sainte Marie, MI
Residential
Rural
100,000
1990
Tribal members had issued complaints arising from the smell
and clouds being produced from a steel plant and paper mill
located on the other side of the Saint Mary's River. The site is
located on Lake Superior State University campus, which is a
residential area. This site includes two sequential PM2 5 filter
based FRM monitors (primary and a collocated), a PM2 5
speciation monitor, a PM2 5 TEOM monitor, an AVOCS
monitor, a PAH monitor, a meteorological station, and a large
paniculate matter collector (dustfall monitor).
LAOR
La Grande, OR
Residential
Urban
55
2003
The La Grande site is a neighborhood-scale site surrounded by
single-family housing with some commercial activities near
by. Schools, a community college, a hospital, businesses, and
some light manufacturing, typical of a rural community, can
be found in fairly close proximity. A variety of sources
impact this site. Forest and agricultural lands surrounding La
Grande are subject to seasonal burning. No major point
sources are located in close proximity to the site; although a
large wood products manufacturing complex is located within
the airshed. Interstate 84, a major trucking route, passes on
the edge of town and a large rail yard is located near the town
center.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
LDTN
MAWI
MIMN
MSTN
MUTX
Location
Loudon, TN
Madison, WI
Minneapolis, MN
Loudon Middle
School, Loudon, TN
Murchison Middle
School, Austin, TX
Land Use
Residential
Residential
Commercial
Residential
Residential
Location
Setting
Suburban
Urban
Urban
Suburban
Suburban
Estimated
Traffic
(# vehicles)
13,360
23,750
10,000
7,287
4,374
Traffic
Year
Estimate
2003
1993
2000
2006
2002
Description of the
Immediate Surroundings
The site was set up due to public concern about air emissions
from several sources in an industrial park. Among these
sources is a very large facility that processes corn to make
corn syrup, A.E. Staley, a sausage casing manufacturer, boat
manufacturer, paper products manufacturer, waste metal
reclamation, waste paper reclamation, and others.
The Madison monitoring site is located on the East High
School's Killiher Athletic field, near the corner of Hoard and
Fifth Street. The monitoring site was originally established in
1992 as an ozone monitoring site. Air toxics monitoring was
added in 2002 as part of the Region 5 State and Local
Regional Air Toxics Monitoring Strategy. The site was
selected to provide new monitoring data for a midsize city
experiencing urban growth.
This site is used to characterize urban air mass in
Minneapolis. The site resides in an urban business district,
primarily offices and retail shops, city government and
warehouses. Nearby sources (less than 1.5 miles from)
include Hennepin Energy Recovery Center (HERC) (which
uses mass burn technology to convert 365,000 tons of garbage
a year into electricity), NRG Energy Center Minneapolis LLC
Steam and Air-Conditioning Supply, and Hennepin County
Medical Center. There is also a high density of mobile
sources and some light manufacturing industries.
The second site at Loudon Middle School in Loudon, TN, was
set up due to public concern about air emissions from several
sources in an industrial park. This site is SW of the LDTN
site and upwind of the industrial sources.
This site is located between a parking lot and the athletic
fields at Murchison Middle School. The site is also located
fairly close to the roadway running in front of the school.
to
I
to
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
Location
Land Use
Location
Setting
Estimated
Traffic
(# vehicles)
Traffic
Year
Estimate
Description of the
Immediate Surroundings
MVWI
Mayville, WI
Agricultural
Rural
5,990
1989/1994
to
Mayville is a designated rural NATTS site. The Mayville air
monitoring station is a multi-parameter site located in rural
southeast Wisconsin. The site is located approximately
45 miles northwest of Milwaukee. The Mayville site is
located directly to the east of the Horicon National Wildlife
Refuge. The monitoring station provides an excellent location
for a rural background air toxics monitoring station. The site
is rural but is located within an area affected by a major urban
area. The site also shows impact on an important wildlife
sanctuary. Current sampling at the site compliments and
supports the air toxics monitoring effort at the site. It will in
some cases allow for comparison of the monitoring
methodologies (PM25 metals vs. PM10 metals). The station
was originally established for the study of ozone, fine
paniculate matter and regional haze. Sampling for hexavalent
chromium began in March 2005 and has continued into 2006.
NBAL
North Birmingham,
AL
Commercial
Urban
2,000
1994
This NAMS neighborhood scale site (located in North
Birmingham) is a super site with a thirty-five year history of
ambient air monitoring. It is an environmental justice site in
that most of the residences in the area are owned and occupied
by minorities. It is located in a valley that is heavily
industrialized. This site yields the one of county's highest
reported particulate levels.
NBIL
Northbrook, IL
Residential
Suburban
29,600
2001
The village of Northbrook is located in northeast Cook
County. This monitoring site is located at the Northbrook
Water Filtration Station at 750 Dundee Road. A forest
preserve is located immediately south with residential areas
farther south (southeast to southwest). Residential areas are
also immediately to the west. Commercial areas are located
along Dundee Road and to the east. A major expressway
(1-94) is located 1 km to the east and north. O'Hare Airport is
located 18 km to the southwest and the Chicago Loop is
located 32 km to the southeast.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
NBNJ
ORFL
PITX
PRRI
PVAL
Location
New Brans wick, NJ
Winter Park, FL
Pickle Research
Center, Austin, TX
Providence, RI
Providence, AL
Land Use
Agricultural
Commercial
Residential
Residential
Residential
Location
Setting
Rural
Urban
Suburban
Urban
Rural
Estimated
Traffic
(# vehicles)
63,000
59,000
33,936
5,500
Unknown
Traffic
Year
Estimate
Unknown
Unknown
2005
1996
Unknown
Description of the
Immediate Surroundings
The New Brunswick site is located in a suburban-agricultural,
residential area and is topographically smooth. The actual site
location is in Rutgers University's Horticultural Farm.
The site is an Urban/Neighborhood spatial scale site to
determine the concentrations of the EPA Criteria pollutants
(and now Air Toxics) to which the area population may be
exposed. The primary emission source is motor vehicles with
some commercial businesses also in the area.
The Pickle Research Center is located in close proximity to
MOP AC (Loop 1), a major Austin-specific north-south
thoroughfare. It is also bounded on one side by Braker Lane,
a four to six lane east-west road in Austin.
The site is on the roof of a rather spread-out, 1 -story building
in a fairly low-income neighborhood of south-Providence. It's
approximately a half-mile from 1-95 where it makes a sharp
curve as it enters the city, where traffic congestion is
common. Narragansett Bay and the Port of Providence are
just a few tenths of a mile further to the east, on the other side
of the highway. There is some industry along the Bay,
including an asphalt plant right next to the curve in the
highway. There is also a highway relocation project that's
been under way for a couple of years.
This SLAMS urban scale general background site (located in
the western-most corner of Jefferson County) was established
in the fall of 1999 to monitor background levels of ozone and
PM2 5 in the county, to get a better idea of what concentrations
were entering the county, and to give better resolution at that
time for the ozone mapping program. It is a rural site in that
there are not many residences in the area and most of the land
use is agricultural. It is located on a rural mountaintop on the
edge of a field used for horse grazing. It is an excellent site for
a background air toxics monitor.
to
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
PXSS
RRTX
RTPNC
S4MO
Location
Phoenix, AZ
Round Rock, TX
Research Triangle
Park, NC
St. Louis, MO
Land Use
Residential
Commercial
Commercial
Residential
Location
Setting
Urban
Suburban
Suburban
Urban
Estimated
Traffic
(# vehicles)
250
20,900
12,000
22,840
Traffic
Year
Estimate
1993
2004
2003
1995
Description of the
Immediate Surroundings
The supersite is intended to represent the central core of the
Phoenix metropolitan area in a high emissions area, and is a
PAMS Type 2 site. The site houses a variety of air
monitoring equipment including criteria pollutant samplers
and analyzers, PAMS and air toxics, total NMHC,
meteorology, visibility /urban haze, and has been selected for
several state and national air monitoring studies. The area
surrounding the site is primarily residential neighborhoods.
There is an interstate highway approximately 1 mile west of
the site, as well as commercial and industrial areas within five
miles of the site.
The RRTX site is located in Round Rock, TX, north of
Austin. The site is located south of FM 3406 and east of the
1-35 corridor, at the dead end of Commerce Boulevard. It was
selected for an emphasis on a variety of factors: upwind of
industrial facilities, population density (weighed heavily), and
mobile source traffic (this location is fairly close to 1-35, the
north-south corridor through Austin into Round Rock).
This site is located on the north side of the EPA campus. It is
approximately 600 meters south of interstate 1-40. There are
trees to the east of the site, sloping down from the site to the
trees. The height of the tallest tress (relative to the sampling
port) to the east is less than 2 times the distance to the trees.
The site has at least 270° clearance around the site.
Blair Street has some industry around it and a fair amount of
industry to the east. The site is also only about 250 meters
from 1-70 (at its closest point).
to
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
Location
Land Use
Location
Setting
Estimated
Traffic
(# vehicles)
Traffic
Year
Estimate
Description of the
Immediate Surroundings
SDGA
Decatur, GA
Residential
Suburban
98,510
1995/1997
Northwesterly winds predominate making this site a short-
range downwind location from Atlanta's urban core.
Undeveloped land surrounds the site but within 1/8 of a mile
there is a residential subdivision, a greenhouse/horse barn and
an athletic field and a high school. Traffic on Wildcat Road (a
dead end, 2-lane blacktop) has considerable vehicular and
diesel traffic during school hours. Three shelters comprise the
dry structures at the site. One houses the PAMS GC,
carbonyls and VOC equipment, another the continuous
monitors, and the third one belongs to Georgia Tech.
Paniculate matter, IMPROVE and PM10 metals reside on
exposed structures.
to
SEWA
Seattle, WA
Industrial
Suburban
20,000
Unknown
The Beacon Hill site is centrally located within the Seattle
urban area. The site is isolated within the confines of the
city's water reservoir. The neatest roads are at least 1 km
away. It is surrounded by residential neighborhoods,
Jefferson Park and a middle school. It is about 100 meters
above sea level. The hill is part of a larger ridge defining the
eastern edge of an area of light industry including a major
seaport, an airport and warehousing and trucking activity
about 4 km west of the site. Interstate freeways and arterial
roads carrying large amounts of traffic are closely situated 2 to
4 km northwest of the site. The site is considered to be
representative of 24 hour average PM2 5 levels within a 20 km
radius.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
Location
Land Use
Location
Setting
Estimated
Traffic
(# vehicles)
Traffic
Year
Estimate
Description of the
Immediate Surroundings
SFSD
Sioux Falls, SD
Residential
Urban
4,320
1999
The SFSD monitoring site is located in Sioux Falls, SD, the
largest city in the state, near two grade schools north of the
site and residential areas on the west, east, and south. The
area within 1 mile of the site is mostly residential with a few
retail businesses. The main industrial area of the city is about
3 miles northwest and 2 miles to the west of the site. The site
was selected because it represents population exposure to
chemical and paniculate emissions from the industrial parts of
the city. The predominant wind direction is northwest for
most of the year with southeast winds during the summer
months.
to
SIAL
Sloss Industries,
Birmingham, AL
Residential
Urban
2,700
1993
This SPM neighborhood scale site (located between North
Birmingham and Tarrant) has been in operation since 1994. It
was established as an environmental justice site to monitor the
emissions of a slag wool plant and a coke plant and is located
next door to several residences in a residential area directly
across the street from the plants.
SJPR
San Juan, PR
Industrial
Suburban
250
1992
The San Juan site is located at Bayamon Municipio, in the
Regional Jail. The San Juan Metropolitan Area (SJMA) is
affected by the emissions from stationary sources and by the
heavy daily traffic. This geographical area is one of the
Island's most polluted areas. The selected location is an open
area representing a neighborhood scale in which the industrial
area merges with the residential areas. The incidence of
respiratory diseases is one of the general concerns (for the
community and for the government). In general, the
concentrations for the criteria pollutants are under the
standards. But air toxics were not sampled for previously.
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
SKFL
SMFL
SPIL
SYFL
TOOK
Location
Skyview Elementary
School, Pinellas Park,
FL
Simmons Park,
Tampa, FL
Schiller Park, IL
Sydney, Plant City,
FL
Site #1,
Tulsa, OK
Land Use
Residential
Unknown
Mobile
Residential
Industrial
Location
Setting
Suburban
Unknown
Suburban
Rural
Urban
Estimated
Traffic
(# vehicles)
50,500
18,700
214,900
5,142
500
Traffic
Year
Estimate
2003
Unknown
2001
2002
1995
Description of the
Immediate Surroundings
This air monitoring site is located in south central Pinellas
County at Skyview Elementary School, 8601 60th St. N.,
Pinellas Park, Florida. This site is a NATTS and samples for
all pollutants/parameters required by NATTS, including
VOCs, carbonyls, metals, PM2 5 speciation, and black carbon.
In addition, measurements are made for wind speed, wind
direction, ambient pressure, and ambient temperature. Site
spatial scale is neighborhood. This is a population-oriented
site.
Neighborhood spatial scale of representativeness characterizes
this monitoring site selected for the Tampa Bay pilot project.
The East Lake monitor is in an area of low population density
and it is representative of urban background concentrations
for the Tampa Bay metro area. Major point sources are
located approximately 8 to 15 km and at 150 m from major
roadways.
This monitoring site is located on a trailer at 4743 Mannheim
Readjust south of Lawrence Ave. and between Mannheim
Road and 1-294. The closest runway at O'Hare Airport is
0.5 km to the northwest. The immediate vicinity is mostly
commercial. Residential areas are located east across 1-294.
The site in Sydney is a NATTS neighborhood/rural site.
Monitoring has been occurring at Sydney for 5 years as a
background site. Current development in the area warranted it
becoming a NATTS site. The Sydney site is also being used
for an intercomparison of the port of Tampa as compared to a
neighbor/rural site.
This site is located approximately % mile east of 1-244. It is
primarily located in an industrial area with Sun Refinery
approximately 2 miles NW and Sinclair Refinery
approximately 1A mile South of site. It contains SO2, H2S,
TSP Metals, and Toxics (VOC and Carbonyl).
to
I
oo
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
TRTX
TSOK
TUMS
TUOK
UNVT
WADC
Location
Travis High School,
Austin, TX
Site #2,
Tulsa, OK
Tupelo, MS
Site #3,
Tulsa, OK
Underbill, VT
Washington, B.C.
Land Use
Residential
Residential
Commercial
Residential
Forest
Commercial
Location
Setting
Suburban
Suburban
Suburban
Urban
Rural
Urban
Estimated
Traffic
(# vehicles)
27,114
62,500
4,900
82,600
1,200
75,800
Traffic
Year
Estimate
2004
2005
1995/1997
Unknown
2005
1991
Description of the
Immediate Surroundings
This site is wedged between a parking lot, tennis courts, and
the baseball field at Travis High School. The site was
selected for an emphasis on a variety of factors: upwind of
industrial facilities, population density (weighed heavily), and
mobile source traffic (this location is fairly close to 1-35 north-
south corridor through Austin into Round Rock). The Travis
High School site is approximately two miles south of Town
Lake/the Colorado River.
The Greenwood site is located approximately 200 yards N-NE
of 1-244 on the Oklahoma State University at Tulsa Campus.
It is primarily neighborhood scale with no major industry
nearby. A railroad track switching site is located
approximately 50 ft. SE of the site. It contains TSP Metals
and Toxics (VOC and Carbonyl).
The Tupelo site is in a light commercial and residential area.
This site was selected because this area is believed to have
high ambient air toxic concentrations based upon information
from the NATA study and Mississippi's major source
emission inventories.
This site is located approximately 50 ft. south of Highway 51,
a major crosstown expressway. It is primarily neighborhood
scale with no major industry nearby and influenced primarily
by downtown traffic. It contains CO, PMio, TSP Metals, and
Toxics (VOC and Carbonyl).
The Underbill monitoring site is in a rural area, about 20 miles
east of Burlington, VT. The site is at the base of Mount
Mansfield, a remote field surrounded by forest.
WADC is located in an open field at the southeast of end of
the McMillian Water Reservoir in Washington, D.C. It is also
located near several heavily traveled roadways. The site is
surrounded by a hospital, a cemetery, and a university.
WADCisaPAMSsite.
to
I
VO
-------
Table 2-1. Descriptions of the 2006 UATMP Monitoring Sites (Continued)
Site Code
WETX
WPIN
YDSP
Location
Webberville Road,
Austin, TX
Washington Park,
Indianapolis, IN
El Paso, TX
Land Use
Residential
Residential
Residential
Location
Setting
Urban
Suburban
Suburban
Estimated
Traffic
(# vehicles)
5,733
11,514
12,400
Traffic
Year
Estimate
2003
1984
2003
Description of the
Immediate Surroundings
The WETX site is located in a parking lot near the
intersections of Webberville Road and Northwestern Avenue
and Webberville Road and Pedermales Street. Railroad tracks
run parallel with Northwestern Avenue. The site was selected
for an emphasis on a variety of factors: upwind of industrial
facilities, population density (weighed heavily), and mobile
source traffic (this location is fairly close to 1-35 north-south
corridor through Austin into Round Rock).
The Washington Park Monitoring Site is located
approximately 3 .75 miles from the center of the city in the
northeast part of Indianapolis. The nearest main roads are 30th
St. (40 meters to the south) and Keystone Ave. (600 meters to
the west). The site is located on the south end of Washington
Park in a mostly residential neighborhood. No significant
industry is located near the site. Washington Park was
established in 1999 as a PM25 and toxics monitoring location.
It collects PM2 .5 mass for compliance purposes, along with
PM2 5 speciation and continuous PM2 5. Air toxics monitoring
began as one of the sites in the four-city Children's Health
Initiative. Currently, samples collected at the site are
analyzed for sixty -two VOC/HAPS. Carbonyl compounds
and metals are also monitored. It is considered a long term
trends site for Indianapolis. Future plans include possible
designation as an NCore Site.
This site is located in a vacant lot adjacent to the YDSP Tribal
Courthouse. According to a 2003 traffic count conducted by
TxDOT, this portion of Socorro Road averages 10,200
vehicles per work day. The site is approximately 50 meters
northwest of the Old Reservation subdivision.
to
o
BOLD = EPA-designated National Air Toxics Trend System (NATTS) site.
-------
Table 2-2. Site Information for the 2006 UATMP Monitoring Sites
Site
Code
AZFL
BAPR
BOMA
BTUT
CANC
CANJ
CHNJ
CHSC
CNEP
CUSD
DEMI
ELNJ
AQS Site Code
12-103-0018
72-017-0003
25-025-0042
49-011-0004
37-123-0001
34-007-0003
34-027-3001
45-025-0001
40-097-9014
46-033-0003
26-163-0033
34-039-0004
Location
Azalea Park, St. Petersburg,
FL
Barceloneta, PR
Boston, MA
Bountiful, UT
Candor, NC
Camden, NJ
Chester, NJ
Chesterfield, SC
Pryor, OK
Custer, SD
Dearborn, MI
Elizabeth, NJ
Population
Residing Within
10 Miles of the
Monitoring Site a
574,226
23,028b
1,562,639
246,163
11,369
2,017,289
241,918
37,525
31,107
5,492
1,167,257
2,187,129
County-level Stationary
Source HAP Emissions in the
2002 NEI '
(tpy)
2,721
406
1,436
851
171
1,267
1,143
463
331
23
8,785
1,903
Closest National
Weather Service Station
St. Petersburg/Whitted
Airport
San Juan, PR, Luis Munoz
Marin Int'l Airport
General Logan Int'l.
Airport
Salt Lake City
International
Moore County Airport
Philadelphia International
Airport
Somerville, NJ, Somerset
Airport
Monroe Airport
Claremore Regional
Airport
Custer County Airport
Detroit Metropolitan
Airport
Newark Int'l Airport
-------
Table 2-2. Site Information for the 2006 UATMP Monitoring Sites (Continued)
Site
Code
ETAL
FLFL
GAFL
GPCO
GPMS
HAKY
IDIN
INDEM
ININ
ITCMI
LDTN
MAWI
MIMN
AQS Site Code
01-073-0028
12-011-1002
12-057-1065
08-077-0018
28-047-0008
21-193-0003
18-097-0085
18-089-0022
18-097-0057
26-033-0901
47-105-0108
55-025-0041
27-053-0966
Location
East Thomas, Birmingham,
AL
Davie, FL
Gandy, Tampa, FL
Grand Junction, CO
Gulfport, MS
Hazard, KY
Stout Field, Indianapolis, IN
Gary, IN
South Harding, Indianapolis,
IN
Sault Sainte Marie, MI
Loudon, TN
Madison, WI
Minneapolis, MN
Population
Residing Within
10 Miles of the
Monitoring Site a
394,178
1,333,555
473,022
111,141
173,435
32,103
591,305
404,985
660,891
21,916
48,670
364,645
1,131,912
County-level Stationary
Source HAP Emissions in the
2002 NEI '
(tpy)
4,562
117,376
7,004
536
3,231
108
3,982
3,125
3,982
184
1,545
2,677
3,352
Closest National
Weather Service Station
Birmingham Int'l Airport
Ft Lauderdale, FL,
Hollywood Int'l Airport
Tampa, FL Int'l Airport
Walker Field Airport
Gulfport/Biloxi Regional
Airport
Julian Carroll Airport
Indianapolis International
Airport
Lancing Municipal Airport
Indianapolis International
Airport
Sault Ste. Marie Municipal
Airport
McGhee Tyson Airport
Dane County Regional-
Traux Field Airport
Minneapolis-St. Paul Int'l
Airport
to
to
to
-------
Table 2-2. Site Information for the 2006 UATMP Monitoring Sites (Continued)
Site
Code
MSTN
MUTX
MVWI
NBAL
NBIL
NBNJ
ORFL
PITX
PRRI
PVAL
PXSS
RRTX
AQS Site Code
47-105-0109
48-453-7001
55-027-0007
01-073-0023
17-031-4201
34-023-0006
12-095-2002
48-453-703
44-007-0022
01-073-1009
04-013-9997
48-491-7004
Location
Loudon Middle School,
Loudon, TN
Murchison Middle School,
Austin, TX
Mayville, WI
North Birmingham, AL
Northbrook, IL
New Brunswick, NJ
Winter Park, FL
Pickle Research Center,
Austin, TX
Providence, RI
Providence, AL
Phoenix, AZ
Round Rock, TX
Population
Residing Within
10 Miles of the
Monitoring Site a
48,670
696,128
24,688
389,196
879,379
796,347
993,441
672,699
685,230
28,587
1,471,887
387,701
County-level Stationary
Source HAP Emissions in the
2002 NEI '
(tpy)
1,545
2,207
539
4,562
21,071
2,427
4,580
2,207
1,251
4,562
8,905
713
Closest National
Weather Service Station
McGhee Tyson Airport
Camp Mabry Army
National Guard
West Bend Municipal
Airport
Birmingham Int'l Airport
Palwaukee Municipal
Airport
Somerville, NJ, Somerset
Airport
Orlando Executive Airport
Camp Mabry Army
National Guard
Theodore F Green State
Airport
Tuscaloosa Municipal
Airport
Phoenix Sky Harbor
International Airport
Georgetown Municipal
Airport
to
to
-------
Table 2-2. Site Information for the 2006 UATMP Monitoring Sites (Continued)
Site
Code
RTPNC
S4MO
SDGA
SEWA
SFSD
SIAL
SJPR
SKFL
SMFL
SPIL
SYFL
TOOK
AQS Site Code
37-063-0014
29-510-0085
13-089-0002
53-033-0080
46-099-0007
01-073-6004
72-021-0006
12-103-0026
12-057-0081
17-031-3103
12-057-3002
40-143-0235
Location
Research Triangle Park, NC
St. Louis, MO
Decatur, GA
Seattle, WA
Sioux Falls, SD
Sloss Industries,
Birmingham, AL
San Juan, PR
Skyview Elementary School,
Tampa, FL
Simmons Park, Tampa, FL
Schiller Park, IL
Sydney, Plant City, FL
Site#l,Tulsa, OK
Population
Residing Within
10 Miles of the
Monitoring Site a
399,239
821,898
728,937
887,100
161,598
389,196
221,546b
699,265
61,186
2,074,707
124,967
459,346
County-level Stationary
Source HAP Emissions in the
2002 NEI '
(tpy)
795
1,975
10,418
4,872
500
4,562
227
2,721
7,004
21,071
7,004
1,733
Closest National
Weather Service Station
Raleigh-Durham Int'l
Airport
St. Louis Downtown
Airport
WB Hartsfield/Atlanta
International Airport
Boeing Field/King County
International Airport
Joe Foss Field Airport
Birmingham Int'l Airport
San Juan, PR, Luis Munoz
Marin Int'l Airport
St. Petersburg-Clearwater
International Airport
Tampa Int'l Airport
O'Hare Int'l Airport
Winter Haven's Gilbert
Airport
Richard Lloyd Jones Jr.
Airport
to
to
-------
Table 2-2. Site Information for the 2006 UATMP Monitoring Sites (Continued)
Site
Code
TRTX
TSOK
TUMS
TUOK
UNVT
WADC
WETX
WPIN
YDSP
AQS Site Code
48-453-7002
40-143-0172
28-081-0005
40-143-0191
50-007-0007
11-001-0043
48-453-7000
18-097-0078
48-141-9001
Location
Travis High School, Austin,
TX
Site #2, Tulsa, OK
Tupelo, MS
Site #3, Tulsa, OK
Underbill, VT
Washington, B.C.
Webberville Road, Austin,
TX
Washington Park,
Indianapolis, IN
El Paso, TX
Population
Residing Within
10 Miles of the
Monitoring Site a
560,699
337,360
71,184
460,577
33,622
1,835,924
677,505
792,104
443,463
County-level Stationary
Source HAP Emissions in the
2002 NEI '
(tpy)
2,207
1,733
916
1,733
555
681
2,207
3,982
2,278
Closest National
Weather Service Station
Austin-Bergstrom Int'l
Airport
Tulsa International Airport
Tupelo Municipal Airport
Richard Lloyd Jones Jr.
Airport
Morrisville-Stowe State
Airport
Ronald Reagan
Washington National
Airport
Austin-Bergstrom Int'l
Airport
Indianapolis International
Airport
El Paso Int'l Airport
to
to
a Reference: http://zipnet.htm
b County population used as surrogate.
c Reference: EPA, 2006a.
-------
Table 2-3. Current UATMP Monitoring Sites with Past Participation
Monitoring Site
Azalea Park, St.
Petersburg, FL (AZFL)
Barceloneta, PR
(BAPR)
Boston, MA (BOMA)
Bountiful, UT (BTUT)
Camden, NJ (CANJ)
Candor, NC (CANC)
Chester, NJ (CHNJ)
Chesterfield, SC
(CHSC)
Custer, SD (CUSD)
Davie, FL (FLFL)
Dearborn, MI (DEMI)
Decatur, GA (SDGA)
East Thomas,
Birmingham, AL
(ETAL)
El Paso, TX (YDSP)
Elizabeth, NJ (ELNJ)
1989
/
/
1990
1991
1992
/
/
1993
1994
1995
/
1996
/
1997
/
1998
/
1999/
2000a
/
/
2001
/
/
/
/
/
/
2002
/
/
/
/
/
/
/
2003
/
/
/
/
/
/
/
/
/
/
2004
/
/
V
/
/
/
/
/
/
/
/
2005
/
/
/
/
/
/
/b
/
/
/
/b
/
/
/
-------
Table 2-3. Current UATMP Monitoring Sites with Past Participation (Continued)
Monitoring Site
Gandy, Tampa, FL
(GAFL)
Gary, IN (INDEM)
Grand Junction, CO
(GPCO)
Gulfport, MS (GPMS)
Hazard, KY (HAKY)
Sault Ste. Marie, MI
(ITCMI)
La Grande, OR
(LAOR)
Loudon, TN (LDTN)
Madison, WI (MAWI)
Mayville, WI (MVWI)
Minneapolis, MN
(MIMN)
Murchison Middle
School, Austin, TX
(MUTX)
New Brunswick, NJ
(NBNJ)
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999/
2000a
2001
'
'
2002
'
'
2003
'
'
/
'
/
/
'
2004
'
/
'
/
'
2005
'
/
'
/c
/b
'
/b
/
/
/b
'
'
'
to
to
-------
Table 2-3. Current UATMP Monitoring Sites with Past Participation (Continued)
Monitoring Site
North Birmingham, AL
(NBAL)
Northbrook, IL (NBIL)
Phoenix, AZ (PXSS)
Pickle Research Center,
Austin, TX (PITX)
Providence, RI (PRRI)
Providence, AL
(PVAL)
Research Triangle Park,
NC (RTPNC)
Round Rock, TX
(RRTX)
San Juan, PR (SJPR)
Schiller Park, IL (SPIL)
Seattle, WA (SEWA)
Simmons Park, Tampa,
FL (SMFL)
Sioux Falls, SD (SFSD)
Skyview Elementary
School, Tampa, FL
(SKFL)
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999/
2000a
/
2001
/
'
/
2002
/
/
2003
/
/
/
/
2004
/
/
'
'
/
/
'
2005
'
/
/b
'
'
'
/
/
/b
'
/
'
to
to
oo
-------
Table 2-3. Current UATMP Monitoring Sites with Past Participation (Continued)
Monitoring Site
Sloss Industries,
Birmingham, AL
(SIAL)
St. Louis, MO (S4MO)
Sydney, Plant City, FL
(SYFL)
Travis High School,
Austin, TX (TRTX)
Tupelo, MS (TUMS)
Underbill, VT (UNVT)
Washington, B.C.
(WADC)
Webberville Rd,
Austin, TX (WETX)
Winter Park, FL
(ORFL)
1989
1990
1991
'
1992
1993
1994
1995
1996
1997
1998
1999/
2000a
2001
/
/
2002
/
/
2003
/
/
'
2004
/
'
/
'
2005
'
/
'
'
/
/b
/b
'
'
to
to
VO
The time period for the 1999/2000 UATMP covers October 1999 to December 2000.
These sites sampled for hexavalent chromium only, and their analysis was presented in a separate report.
c This site sampled as part of the Katrina Monitoring Effort beginning in October 2005.
-------
Target pollutant concentrations measured during the 2006 UATMP varied significantly
from monitoring site to monitoring site. As discussed throughout this report, the proximity of
the monitoring locations to different emissions sources, especially industrial facilities and
heavily traveled roadways, often explains the observed spatial variations in ambient air quality.
To provide a first approximation of the contributions of stationary source emissions on ambient
air quality at each site, Table 2-2 lists the stationary source hazardous air pollutant (HAP)
emissions in the monitoring site's residing county, according to the 2002 NEI, as well as the
number of people living within 10 miles of each monitoring location.
At every UATMP monitoring site, the sample collection equipment was installed either
in a temperature-controlled enclosure (usually a trailer or a shed) with the sampling probe inlet
exposed to the ambient air or as a stand alone sampler. With this common setup, every UATMP
monitoring site sampled ambient air at heights approximately 5 to 20 feet above local ground
level.
For record keeping and reporting purposes, each of these sites was assigned:
• A unique four- or five-letter UATMP site code - used to track samples from the
monitoring sites to the ERG laboratory; and
• A unique nine-digit AQS site code - used to index monitoring results in the AQS
database.
This report cites the UATMP site code when presenting selected monitoring results.
2.2 Methods Used and Pollutants Targeted for Monitoring
Urban air pollution typically contains hundreds of components, including, but not limited
to, volatile organic compounds (VOC), carbonyl compounds, metals, and particulate matter.
Because the sampling and analysis required to monitor for every component of air pollution has
been prohibitively expensive, the UATMP instead focuses on specific pollutants, as listed below:
Compendium Method TO-15 was used to measure ambient air concentrations of
61 VOC and used in conjunction with the Technical Assistance Document (TAD) for
2-30
-------
sampling and analysis of ozone precursors to measure 80 Speciated Nonmethane
Organic Compounds (SNMOC);
• Compendium Method TO-11A was used to measure ambient air concentrations of
15 carbonyl compounds;
• Compendium Method TO-13A was used to measure ambient air concentrations of 19
SVOC, or SW846 Method 8270 was used to measure ambient air concentrations of
106SVOCatGPMS;
• Compendium MethodIO-3.5 was used to measure ambient concentration of
11 metals; and
• EPA-approved hexavalent chromium method was used to measure ambient
concentrations of hexavalent chromium.
Carbon disulfide was added to the VOC list beginning in January 2006. Tables 2-4
through 2-9 identify the specific target pollutants and their corresponding experimentally-
determined range of and average method detection limits (MDL).
All detection limits of the analytical methods must be considered carefully when
interpreting the corresponding ambient air monitoring data. By definition, detection limits
represent the lowest concentrations at which laboratory equipment have been experimentally
determined to reliably quantify concentrations of selected pollutants to a specific confidence
level. If a chemical concentration in ambient air does not exceed the method sensitivity (as
gauged by the detection limit), the analytical method might not differentiate the pollutant from
other pollutants in the sample or from the random "noise" inherent in laboratory analyses. While
quantification below the MDL is possible, the measurement reliability is lower. Therefore, when
samples contain concentrations at levels below their respective detection limits, multiple
analyses of the same sample may lead to a wide range of results, including highly variable
concentrations or "non-detect" observations. Data analysts must exercise caution when
interpreting monitoring data with many reported concentrations at levels near or below the
corresponding detection limits.
MDLs are determined at the ERG laboratory using 40 CFR, Part 136 Appendix B
procedures (EPA, 2005b) in accordance with the specifications presented in the NATTS TAD
2-31
-------
(EPA, 2007a). This procedure involves analyzing at least seven replicate standards prepared
on/in the appropriate sampling media (per analytical method). Instrument detection limits are
not determined (replicates of standards only) because sample contamination and preparation
variability would not be considered.
Because non-detect results significantly limit the range of data interpretations for ambient
air monitoring programs, participating agencies should note that the approach for treating
non-detects may slightly affect the magnitude of the calculated central tendency concentrations,
especially for pollutants with a low detection rate. The non-detects were treated as valid data
points. For purposes of risk analysis, non-detects were substituted with one-half of the MDL on
a target pollutant basis to calculate seasonal and annual averages.
The following discussion presents an overview of the sampling and analytical methods.
For detailed descriptions of the methods, readers should refer to EPA's original documentation of
the Compendium Methods (EPA, 1996; EPA, 1998; EPA, 1999a; EPA, 1999b; EPA, 1999c;
EPA, 1999d; EPA, 2006b).
2.2.1 VOC and SNMOC Sampling and Analytical Method
VOC and SNMOC sampling and analysis was performed in accordance with a
combination of EPA Compendium Method TO-15 and the procedure presented in EPA's
"Technical Assistance Document for Sampling and Analysis of Ozone Precursors" (EPA, 1998).
Ambient air samples for VOC analysis were collected in passivated stainless steel canisters. The
central laboratory distributed the prepared canisters (i.e., cleaned and evacuated) to the UATMP
monitoring sites before each scheduled sample collection event, and site operators connected the
canisters to air sampling equipment prior to each sampling day. Before use in the field, the
passivated canisters had internal pressures much lower than atmospheric pressure. Using this
pressure differential, ambient air naturally flowed into the canisters once they were opened. A
mass flow controller on the sampling device inlet ensured that ambient air entered the canister at
an integrated constant rate across the collection period. At the end of the 24-hour sampling
2-32
-------
period, a solenoid valve automatically stopped ambient air from flowing into the canister. Site
operators recovered and returned the canisters to the central laboratory for analysis.
By analyzing each sample with gas chromatography incorporating mass spectrometry and
flame ionization detection (GC/MS-FID), laboratory staff determined ambient air concentrations
of 61 VOC, 80 SNMOC, and total nonmethane organic compounds (TNMOC). TNMOC is the
sum of all hydrocarbon concentrations within the sample. Because isobutene and 1-butene elute
from the gas chromatography (GC) column at the same time, the SNMOC analytical method
reports only the sum of the concentrations for these compounds, and not the separate
concentrations for each compound. The same measurement applies to w-xylene and/>-xylene for
both the VOC and SNMOC methods. These raw data are presented in Appendices I and J.
Regarding samples of acetonitrile, laboratory analysts have indicated that the values may
be artificially high (or nonexistent) due to site conditions and potential cross-contamination with
concurrent sampling of carbonyl compounds using Method TO-11A. The inclusion of
acetonitrile in data analysis calculations needs to be determined on a site-specific basis by the
agency responsible for the site. As such, acetonitrile results are excluded from the program-wide
and site-specific pollutant of interest designation and corresponding risk analysis.
Table 2-4 summarizes the MDLs for the laboratory analysis of the VOC samples and
Table 2-5 summarizes the MDLs for the SNMOC samples. Although the sensitivity of the
analytical method varies from pollutant-to-pollutant and site-to-site, the MDL for VOC
Table 2-4. VOC Method Detection Limits
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
MDL
(ppbv)
0.0987
0.0235
0.1066
0.0572
0.0128
0.0053
2-33
-------
Table 2-4. VOC Method Detection Limits (Continued)
Pollutant
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Tetrachloride
Carbon Bisulfide
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
/w-Dichlorobenzene
o-Dichlorobenzene
/>-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
/ra«5-l,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl tert-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tert-Butyl Ether
n-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
MDL
(ppbv)
0.0192
0.0075
0.0172
0.0108
0.0069
0.0097
0.0091
0.0053
0.0089
0.0045
0.0150
0.0055
0.0224
0.0103
0.0184
0.0047
0.0061
0.0071
0.0051
0.0063
0.0154
0.0146
0.0162
0.0186
0.0176
0.0333
0.0142
0.0097
0.0032
0.0118
0.0077
0.0053
0.0191
0.0442
0.0079
0.0067
0.0031
0.0065
0.0097
0.0105
0.0136
0.0113
0.0053
2-34
-------
Table 2-4. VOC Method Detection Limits (Continued)
Pollutant
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
Trichloroethylene
Trichlorofluoromethane
Trichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1 ,3 ,5-Trimethylbenzene
Vinyl Chloride
m,p-Xylenel
o-Xylene
MDL
(ppbv)
0.0175
0.0033
0.0063
0.0107
0.0073
0.0124
0.0041
0.0045
0.0087
0.0095
0.0045
1 Because /w-xylene and^-xylene elute from the GC column at the same time, the
VOC analytical method can report only the sum of/w-xylene and^-xylene
concentrations and not concentrations of the individual compounds.
Table 2-5. SNMOC Method Detection Limits1
Pollutant
Acetylene
Benzene
1,3 -Butadiene
w-Butane
c/s-2-Butene
/raws-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
w-Decane
7-Decene
/w-Diethylbenzene
/>-Diethylbenzene
2,2-Dimethylbutane
2,3 -Dimethylbutane
2,3 -Dimethylpentane
2,4-Dimethylpentane
w-Dodecane
7-Dodecene
Ethane
2-Ethyl-l-butene
Ethylbenzene
MDL
(ppbC)
0.0978
0.2600
0.2367
0.1989
0.2150
0.1839
0.2617
0.1955
0.3200
0.3889
0.4772
0.4772
0.4716
0.1578
0.2511
0.3828
0.2989
0.7133
0.7133
0.0867
0.4505
0.2467
2-35
-------
Table 2-5. SNMOC Method Detection Limits1 (Continued)
Pollutant
Ethylene
/w-Ethyltoluene
o-Ethyltoluene
£>-Ethyltoluene
w-Heptane
7-Heptene
w-Hexane
7-Hexene
c/s-2-Hexene
trans-2-tlexene
Isobutane
Isobutene/ 1 -Butene3
Isopentane
Isoprene
Isopropylbenzene
2-Methyl-l-butene
3 -Methyl- 1 -butene
2-Methyl-l-pentene
4-Methyl-l-pentene
2-Methyl-2-butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2-Methylhexane
3-Methylhexane
2-Methylpentane
3-Methylpentane
w-Nonane
7-Nonene
w-Octane
7-Octene
w-Pentane
7-Pentene
c/5-2-Pentene
trans-2-Pentene
a-Pinene
6-Pinene
Propane
w-Propylbenzene
Propylene
MDL
(ppbC)
0.0794
0.3572
0.3389
0.4177
0.2411
0.3828
0.2033
0.4489
0.4505
0.4505
0.0983
0.1867
0.1878
0.2644
0.3411
0.3200
0.3200
0.4505
0.4505
0.3200
0.1867
0.2144
0.2389
0.1761
0.2933
0.2300
0.1761
0.2489
0.3766
0.4733
0.2122
0.4889
0.1655
0.2194
0.3089
0.1433
0.4772
0.4772
0.1139
0.3777
0.1200
2-36
-------
Table 2-5. SNMOC Method Detection Limits1 (Continued)
Pollutant
Propyne
Styrene
Toluene
w-Tridecane
7-Tridecene
1 ,2,3 -Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 ,3 ,5-Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3 ,4-Trimethylpentane
w-Undecane
7-Undecene
wj-Xylene/^-Xylene2
o-Xylene
MDL
(ppbC)
0.1233
0.4889
0.2839
0.7133
0.7133
0.3377
0.4650
0.3011
0.4889
0.2317
0.2184
0.3350
0.3350
0.3900
0.2655
Concentration in ppbC = concentration in ppbv x number of carbon atoms in compound.
2 Because isobutene and 1-butene elute from the GC column at the same time, the SNMOC analytical
method can report only the sum of concentrations for these two compounds and not concentrations of
the individual compounds. For the same reason, the /w-xylene and^-xylene concentrations are reported
as a sum.
reported for every pollutant is lower than 0.11 parts per billion by volume (ppbv). SNMOC
detection limits are expressed in parts per billion-carbon (ppbC). All of the SNMOC MDLs are
less than 0.72 ppbC.
2.2.2 Carbonyl Sampling and Analytical Method
Following the specifications of EPA Compendium Method TO-11 A, ambient air samples
for carbonyl analysis were collected by passing ambient air through cartridges containing silica
gel coated with 2,4-dinitrophenylhydrazine (DNPH), a compound known to react selectively and
reversibly with many aldehydes and ketones. Carbonyl compounds in ambient air are retained in
the sampling cartridge, while other compounds pass through the cartridge without reacting with
the DNPH-coated matrix. As with the VOC sampling, the ERG laboratory distributed the DNPH
cartridges to the monitoring sites, and site operators connected the cartridges to the air sampling
equipment. After each 24-hour sampling period, site operators recovered and returned the
cartridges to the central laboratory for chemical analysis.
2-37
-------
To quantify concentrations of carbonyls in the sampled ambient air, laboratory analysts
eluted the exposed DNPH cartridges with acetonitrile. This solvent elution liberated a solution
of DNPH derivatives of the aldehydes and ketones for analysis. High-performance liquid
chromatography (HPLC) analysis and ultraviolet detection of these solutions determined the
relative amounts of individual carbonyls present in the original air sample. Because
butyraldehyde/isobutyraldehyde elute from the HPLC column at the same time, the carbonyl
analytical method can report only the sum of the concentrations for these compounds, and not
the separate concentrations for each compound. For the same reason, the analytical method
reports only the sum of the concentrations for the three tolualdehydes isomers, as opposed to
reporting separate concentrations for the three individual compounds. These raw data are
presented in Appendix K.
Table 2-6 lists the MDLs reported by the ERG laboratory for measuring concentrations
of 15 carbonyl compounds. Although the sensitivity of the analytical method varies from
pollutant-to-pollutant and from site-to-site, the detection limit reported by the ERG laboratory
for every pollutant is less than 0.01 ppbv for a 1000 liter (L) sample volume.
2.2.3 Semivolatile Sampling and Analytical Method
Semivolatile sampling was performed in accordance with EPA Compendium Method
TO-13A or SW846/Method 8270C. Most sites that sampled SVOC did so according to Method
TO-13A. ERG supplied prepared sampling media and received the samples from the sites for
these analyses. Sample collection modules containing PUF, petri dishes containing filters, and
Chain of Custody forms and all associated documentation, were shipped to ERG. Upon receipt
of the collection modules at the ERG laboratory, sample preparation and analysis procedures are
based on Compendium Method TO-13 A. SVOC raw data are presented in Appendix L.
2-38
-------
Table 2-6. Carbonyl Method Detection Limits1
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde3
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes3
Valeraldehyde
Minimum
MDL
(ppbv)
0.0020
0.0030
0.0007
0.0005
0.0005
0.0003
0.0020
0.0006
0.0005
0.0006
0.0009
0.0004
Maximum
MDL
(ppbv)
0.0490
0.0790
0.0220
0.0160
0.0150
0.0100
0.1560
0.0180
0.0140
0.0180
0.0280
0.0130
Average
MDL
(ppbv)2
0.0054
0.0082
0.0023
0.0018
0.0016
0.0011
0.0065
0.0020
0.0014
0.0021
0.0030
0.0013
1 Assumes a 1000 L sample volume.
2 The MDLs in the table above represent the average MDL for each pollutant, as the MDL varies
slightly based on sample volume.
3 Because butyraldehyde/isobutyraldehyde elute from the HPLC column at the same time, the
carbonyl analytical method can report only the sum of concentrations for these two compounds
and not concentrations of the individual compounds. For the same reason, the analytical method
also reports only the sum of concentrations for the three tolualdehydes isomers, as opposed to
reporting separate concentrations for the three individual compounds.
GPMS, the post-Katrina monitoring site, also sampled SVOC during 2006. However,
this site used a different collection media in order to expand the number of pollutants monitored
(19 for Method TO-13A vs. 106 for Method 8270C). Similar to TO-13A, ERG supplied
prepared sampling media and received the collected samples from the sites for analysis.
Semivolatile sampling modules containing prepared XAD-2® resin, petri dishes containing
filters, and Chain of Custody forms and all associated documentation, were shipped to ERG.
Upon receipt of the collection modules at the ERG laboratory, sample preparation and analysis
procedures were conducted based on SW846 Method 8270. GPMS SVOC raw data are also
presented in Appendix L.
Table 2-7a lists the MDLs for SVOC target pollutants for Method TO-13 A. MDLs for
SVOC ranged from 0.06 to 0.52 picograms per cubic meters (pg/m3), based on an average
sample volume of 200 cubic meters (m3). Table 2-7b lists the MDLs for the laboratory analysis
2-39
-------
Table 2-7*. SVOC (TO-13A) Method Detection Limits1
Pollutant
Acenaphthene
Acenaphthylene
Anthracene
Benzo (a) anthracene
Benzo (a) pyrene
Benzo (b) fluoranthene
Benzo (e) pyrene
Benzo (g,h,i) perylene
Benzo (k) fluoranthene
Chrysene
Coronene
Dibenz (a,h) anthracene
Fluoranthene
Fluorene
Indeno( 1,2,3 -cd)py rene
Naphthalene
Perylene
Phenanthrene
Pyrene
Minimum
MDL
(pg/m3)
0.078
0.085
0.054
0.047
0.067
0.051
0.034
0.032
0.037
0.045
0.031
0.033
0.055
0.132
0.047
0.283
0.044
0.051
0.067
Maximum
MDL
(pg/m3)
0.298
0.326
0.205
0.181
0.254
0.196
0.128
0.122
0.141
0.173
0.117
0.124
0.209
0.503
0.179
1.080
0.170
0.196
0.254
Average
MDL
(Pg/m3)2
0.143
0.157
0.099
0.087
0.122
0.094
0.062
0.059
0.068
0.083
0.056
0.060
0.101
0.242
0.086
0.520
0.082
0.094
0.122
1 Assumes a 200 m3 sample volume.
2 The MDLs in the table above represent the average MDL for each pollutant, as
the MDL varies slightly based on sample volume.
Table 2-7b. SVOC (SW846/8270C) Method Detection Limits1
Pollutant
Acenaphthene
Acenaphthylene
Acetophenone
2-Acetylaminofluorene
4-Aminobiphenyl
Aniline
Anthracene
Azobenzene
Benzidine
Benzo (a) anthracene
Benzo (a) pyrene
Benzo (b) fluoranthene
Benzo (g,h,i) perylene
Minimum
MDL
(Mg/m3)
0.0002
0.0002
0.0003
0.0002
0.0011
0.0005
0.0003
0.0003
0.0021
0.0002
0.0002
0.0003
0.0002
Maximum
MDL
(Mg/m3)
0.1040
0.0906
0.1420
0.0776
0.5560
0.2720
0.1290
0.1290
1.4900
0.0776
0.0776
0.1420
0.1160
Average
MDL
(Mg/m3)2
0.0327
0.0279
0.0379
0.0323
0.1122
0.0609
0.0423
0.0280
0.8677
0.0272
0.0188
0.0354
0.0425
2-40
-------
Table 2-7b. SVOC (SW846/8270C) Method Detection Limits1 (Continued)
Pollutant
Benzo (k) fluoranthene
Benzyl alcohol
Bis(2-chloroethoxy)methane
Bis(2-chloroethyl)ether
Bis(2-chloroisopropyl)ether
Bis(2-ethylhexyl)phthalate
4-Bromophenyl phenyl ether
Butyl benzyl phthalate
Carbazole
4-Chloro-3 -methylphenol
4-Chloroaniline
Chlorobenzilate
2-Chloronaphthalene
2-Chlorophenol
4-Chlorophenyl phenyl ether
Chrysene
Diallate
Dibenz (a,h) anthracene
Dibenzofuran
1,2-Dichlorobenzene
1 , 3 -Dichlorobenzene
1,4-Dichlorobenzene
3,3 '-Dichlorobenzidine
2,4-Dichlorophenol
2,6-Dichlorophenol
Diethyl phthalate
Dimethyl phthalate
4-Dimethylaminoazobenzene
7,12-Dimethylbenz (a) anthracene
3,3 '-Dimethylbenzidine
2,4-Dimethylphenol
Di-n-butyl phthalate
4,6-Dinitro-2 -methylphenol
1 , 3 -Dinitrobenzene
2,4-Dinitrophenol
2,4-Dinitrotoluene
2,6-Dinitrotoluene
Di-n-octyl phthalate
Dinoseb
Diphenylamine
Ethyl Methanesulfonate
Fluoranthene
Minimum
MDL
(Mg/m3)
0.0002
0.0004
0.0003
0.0003
0.0002
0.0002
0.0003
0.0002
0.0002
0.0003
0.0004
0.0001
0.0002
0.0003
0.0002
0.0003
0.0002
0.0002
0.0001
0.0003
0.0002
0.0002
0.0003
0.0002
0.0002
0.0002
0.0002
0.0002
0.0002
0.0021
0.0014
0.0002
0.0003
0.0003
0.0003
0.0003
0.0003
0.0002
0.0003
0.0011
0.0003
0.0002
Maximum
MDL
(Mg/m3)
0.1160
0.1810
0.1420
0.1420
0.1160
0.1040
0.1290
0.1160
0.1160
0.1420
0.1940
0.0647
0.0906
0.1550
0.1040
0.1290
0.1040
0.1040
0.0647
0.1290
0.1040
0.1160
0.1550
0.1160
0.1160
0.0906
0.0906
0.0906
0.1160
1.0500
0.6860
0.1040
0.1420
0.1550
0.1680
0.1420
0.1420
0.0906
0.1290
0.5560
0.1550
0.0776
Average
MDL
(Mg/m3)2
0.0375
0.0465
0.0362
0.0362
0.0333
0.0344
0.0457
0.0358
0.0400
0.0396
0.0479
0.0233
0.0295
0.0410
0.0361
0.0347
0.0302
0.0344
0.0249
0.0347
0.0293
0.0341
0.0385
0.0350
0.0350
0.0354
0.0287
0.0228
0.0375
0.2643
0.1318
0.0327
0.0370
0.0444
0.0778
0.0412
0.0362
0.0262
0.0406
0.1122
0.0452
0.0289
2-41
-------
Table 2-7b. SVOC (SW846/8270C) Method Detection Limits1 (Continued)
Pollutant
Fluorene
Hexachlorobenzene
Hexachlorobutadiene
Hexachlorocyclopentadiene
Hexachloroethane
Hexachloropropene
Indeno( 1 ,2,3 -cd)pyrene
Isodrin
Isophorone
Isosafrole
Methyl Methanesulfonate
3 -Methy Icholanthrene
2-Methylnaphthalene
2-Methylphenol
3 & 4-Methylphenol
Naphthalene
1 ,4-Naphthoquinone
1-Naphthylamine
2-Naphthylamine
2-Nitro aniline
3-Nitroaniline
4-Nitroaniline
Nitrobenzene
5 -Nitro -o -toluidine
2-Nitrophenol
4-Nitrophenol
N-Nitrosodiethylamine
N-Nitrosodimethylamine
N-Nitrosodi-n-butylamine
N-Nitrosodi-n-propylamine
N-Nitrosomethylethylamine
N-Nitrosopiperidine
N-Nitrosopyrrolidine
Pentachlorobenzene
Pentachloroethane
Pentachloro nitrobenzene
Pentachlorophenol
Phenacetin
Phenanthrene
Phenol
2-Picoline
Pronamide
Minimum
MDL
(Mg/m3)
0.0002
0.0002
0.0003
0.0004
0.0002
0.0003
0.0000
0.0002
0.0002
0.0002
0.0003
0.0003
0.0003
0.0004
0.0004
0.0003
0.0002
0.0010
0.0010
0.0003
0.0002
0.0003
0.0002
0.0002
0.0004
0.0003
0.0003
0.0003
0.0002
0.0002
0.0003
0.0002
0.0003
0.0002
0.0004
0.0003
0.0003
0.0002
0.0002
0.0003
0.0014
0.0003
Maximum
MDL
(Mg/m3)
0.0906
0.1040
0.1550
0.2200
0.1040
0.1420
0.0313
0.0906
0.1160
0.1160
0.2390
0.1290
0.1290
0.1940
0.1810
0.1420
0.1160
0.5180
0.5050
0.1290
0.1040
0.1290
0.1160
0.1160
0.1940
0.1420
0.2210
0.2020
0.1040
0.1160
0.1420
0.1040
0.1550
0.1040
0.1810
0.1550
0.1550
0.1040
0.1160
0.1680
0.6730
0.1290
Average
MDL
(Mg/m3)2
0.0287
0.0310
0.0418
0.0550
0.0344
0.0387
0.0173
0.0304
0.0316
0.0350
0.1393
0.0423
0.0390
0.0521
0.0490
0.0412
0.0442
0.1121
0.1022
0.0381
0.0276
0.0356
0.0324
0.0316
0.0471
0.0513
0.1285
0.1181
0.0344
0.0417
0.0430
0.0335
0.0494
0.0335
0.0490
0.0469
0.0452
0.0344
0.0358
0.0425
0.1421
0.0381
2-42
-------
Table 2-7b. SVOC (SW846/8270C) Method Detection Limits1 (Continued)
Pollutant
Pyrene
Pyridine
Safrole
1,2,4,5-Tetrachlorobenzene
2,3,4,6-Tetrachlorophenol
o-Toluidine
1,2,4-Trichlorobenzene
2,4,5-Trichlorophenol
2,4,6-Trichlorophenol
Minimum
MDL
(Mg/m3)
0.0002
0.0005
0.0003
0.0003
0.0003
0.0003
0.0002
0.0003
0.0002
Maximum
MDL
(Mg/m3)
0.1160
0.3500
0.1290
0.1290
0.1420
0.1550
0.1160
0.1420
0.1040
Average
MDL
(Mg/m3)2
0.0341
0.2035
0.0373
0.0398
0.0379
0.0427
0.0341
0.0396
0.0302
1 Assumes a 200 m3 sample volume.
2 The MDLs in the table above represent the average MDL for each pollutant, as the
MDL varies slightly based on sample volume.
of the SVOC Method 8270 samples. MDLs for SVOC ranged from 0.02 to 0.87 micrograms per
cubic meter (|ig/m3), in an average sample volume of 300 m3.
2.2.4 Metals Sampling and Analytical Method
Sampling for the determination of metals in particulate matter was performed by the sites
in accordance with EPA Compendium Method IO-3.5. Filters with Chain of Custody forms and
all associated documentation were shipped to the ERG laboratory from the field. Upon receipt,
the filters were analyzed by the ERG laboratory. Metals raw data are presented in Appendix M.
Table 2-8 lists the MDLs for the analysis of the metal samples. Two types of filters were
utilized. Sites sampled for PMi0 or Total Suspended Particulate (TSP) on either 47 mm Teflon®
or 8 x 10" Quartz filters. Therefore, because of the difference in the filter collection media,
there are two sets of MDLs listed in Table 2-8. The MDLs ranged from 0.02 to 0.60 nanograms
per cubic meter (ng/m3) for the PMio filters and from 0.02 to 0.48 ng/m3 for the TSP filters.
2-43
-------
Table 2-8. Metals Method Detection Limits
Pollutant
Minimum
MDL
(ng/m3)
Maximum
MDL
(ng/m3)
Average
MDL
(ng/m3)1
8 X 10" Quartz Filters
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Lead
Manganese
Mercury
Nickel
Selenium
0.0030
0.0030
0.0020
0.0020
0.0200
0.0030
0.0040
0.0040
0.0090
0.0090
0.0040
0.2100
0.2600
0.2800
0.1800
3.6400
0.2400
0.4100
0.2400
0.2800
0.8300
0.1800
0.0350
0.0329
0.0361
0.0255
0.5981
0.0315
0.0755
0.1072
0.1748
0.1876
0.0316
47mm Teflon® Filters
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Lead
Manganese
Mercury
Nickel
Selenium
0.0100
0.0090
0.0200
0.0080
0.1420
0.0100
0.0180
0.0160
0.0090
0.0880
0.0180
0.0400
0.0300
0.0300
0.0200
0.6300
0.0300
0.0800
0.1600
0.2600
0.2300
0.0300
0.0274
0.0209
0.0247
0.0180
0.4780
0.0210
0.0638
0.1157
0.1945
0.1761
0.0263
1 The MDLs in the table above represent the average MDL for each
pollutant, as the MDL varies slightly based on sample volume.
2.2.5 Hexavalent Chromium Sampling and Analytical Method
Hexavalent chromium was measured using an EPA-approved approach. For a detailed
description of the EPA-approved approach, refer to the Standard Operating Procedure for the
Determination of Hexavalent Chromium in Ambient Air Analyzed by Ion Chromatography (1C)
(EPA, 2006b). The MDL is experimentally determined for each site at the ERG analytical
laboratory; the average MDL for the program, which is presented in Table 2-9, was 0.013 ng/m3.
Raw data are presented in Appendix N.
2-44
-------
Table 2-9. Hexavalent Chromium Method Detection Limit
Pollutant
Hexavalent Chromium
Minimum
MDL
(ng/m3)
0.0056
Maximum
MDL
(ng/m3)
0.0317
Average
MDL
(ng/m3)1
0.0129
1 The MDL in the table above represents the average MDL for this pollutant,
as the MDL varies slightly based on sample volume.
2.3 Sample Collection Schedules
Table 2-10 presents the first and last date on which sample collection occurred for each
monitoring location. The UATMP monitoring sites started sampling in January 2006 and
stopped sampling in December 2006, with a few exceptions. Six sites began sampling after
January 2006:
• Loudon, TN site (MSTN) started in February 2006;
• Tulsa, OK site (TSOK) started sampling carbonyls and VOC in June 2006;
• Indianapolis, IN site (WPIN) started in June 2006;
• Cherokee Nation site (CNEP) started in September 2006; and
• Indianapolis, IN sites (IDIN and ININ) started in October 2006.
• Tulsa, OK sites (TOOK, TSOK, and TUOK) began sampling metals in October 2006.
Sixteen sites ended sampling before December 2006:
• La Grande, OR and Madison, WI sites (LAOR and MAWI) ended in February 2006;
• El Paso, TX site (YDSP) ended in March 2006;
• Minneapolis, MN site (MIMN) ended metals sampling in March 2006, and VOC and
carbonyl sampling in April 2006;
• North Carolina sites (CANC and RTPNC) ended in June 2006;
• The Birmingham, AL sites (ETAL, NBAL, PVAL, and SIAL) and Austin, TX sites
(MUTX, PITX, RRTX, TRTX, and WETX) ended in late June or early July 2006;
and
• The Ft. Lauderdale, FL site (FLFL) ended in October 2006.
2-45
-------
Table 2-10. Sampling Schedules and Completeness
Site
AZFL
BAPR
BOMA
BTUT
CANC
CANJ
CHNJ
CHSC
CNEP
CUSD
DEMI
ELNJ
ETAL
GAFL
Monitoring Period"
Starting
Date
1/5/06
1/5/06
1/5/06
1/5/06
1/11/06
1/5/06
1/5/06
1/5/06
9/26/06
1/5/06
1/5/06
1/5/06
1/11/06
1/5/06
Ending
Date
12/31/06
12/31/06
12/31/06
12/31/06
6/28/06
12/31/06
12/31/06
12/31/06
12/26/06
12/31/06
12/31/06
12/31/06
6/28/06
12/31/06
Carbonyl
A
61
59
60
9
57
58
62
60
59
15
61
B
61
59
60
9
59
60
62
60
60
15
61
C
100
100
100
100
97
97
100
100
98
100
100
voc
A
57
59
53
58
14
61
58
58
15
B
59
60
58
60
16
62
61
60
15
C
97
98
91
97
88
98
95
97
100
Hexavalent
Chromium
A
61
59
59
59
16
B
61
61
61
61
17
C
100
97
97
97
94
Metals
A
56
58
15
B
56
58
15
C
100
100
100
SNMOC
A
59
61
B
60
62
C
98
98
svoc
A
16
B
17
C
94
to
a Begins with 1st valid sample and may include all six analyses.
A = Valid Samples
B = Total Number of Samples
C = Completeness (%)
-------
Table 2-10. Sampling Schedules and Completeness (Continued)
Site
GAFL
GPCO
GPMS
HAKY
IDIN
INDEM
ININ
ITCMI
LAOR
LDTN
MAWI
MIMN
MSTN
MUTX
Monitoring Period"
Starting
Date
1/5/06
1/5/06
1/2/06
1/5/06
10/2/06
1/5/06
10/2/06
1/5/06
1/5/06
1/5/06
1/5/06
1/5/06
2/22/06
1/5/06
Ending
Date
12/31/06
12/31/06
12/31/06
12/31/06
12/31/06
12/31/06
12/31/06
12/31/06
2/4/06
12/31/06
2/22/06
4/23/06
12/31/06
6/28/06
Carbonyl
A
61
61
71
16
54
14
56
8
17
51
17
B
61
61
74
16
55
15
57
8
17
54
17
C
100
100
96
100
98
93
98
100
100
94
100
voc
A
61
68
55
8
16
49
15
B
61
72
57
8
17
54
17
C
100
94
96
100
94
91
88
Hexavalent
Chromium
A
60
2
59
16
6
B
61
2
61
16
6
C
98
100
97
100
100
Metals
A
42
13
16
12
B
48
16
16
13
13
C
88
81
100
92
100
SNMOC
A
62
15
B
66
17
C
94
88
svoc
A
61
60
B
63
62
C
97
97
to
a Begins with 1st valid sample and may include all six analyses.
A = Valid Samples
B = Total Number of Samples
C = Completeness (%)
13
-------
Table 2-10. Sampling Schedules and Completeness (Continued)
Site
MVWI
NBAL
NBIL
NBNJ
ORFL
PITX
PRRI
PVAL
PXSS
RRTX
RTPNC
S4MO
SDGA
SEWA
Monitoring Period"
Starting
Date
1/5/06
1/11/06
1/5/06
1/5/06
1/5/06
1/5/06
1/5/06
1/11/06
1/5/06
1/5/06
1/11/06
1/5/06
1/5/06
1/5/06
Ending
Date
12/31/06
7/10/06
12/31/06
12/31/06
12/31/06
6/28/06
12/31/06
6/28/06
12/31/06
7/1/06
6/28/06
12/31/06
12/31/06
12/31/06
Carbonyl
A
17
61
53
61
16
16
16
9
61
B
19
61
60
61
17
17
17
9
62
C
89
100
88
100
94
94
94
100
98
voc
A
17
60
51
16
16
15
59
B
20
61
60
18
17
18
62
C
85
98
85
89
94
83
95
Hexavalent
Chromium
A
60
15
59
61
17
59
61
57
13
B
61
16
61
61
18
61
61
61
17
C
98
94
97
100
94
97
100
93
76
Metals
A
30
62
17
15
59
15
59
B
30
62
17
15
63
15
60
C
100
100
100
100
94
100
98
SNMOC
A
57
16
15
B
58
18
18
C
98
89
83
svoc
A
15
15
B
16
18
C
94
83
to
-k
oo
a Begins with 1st valid sample and may include all six analyses.
A = Valid Samples
B = Total Number of Samples
C = Completeness (%)
-------
Table 2-10. Sampling Schedules and Completeness (Continued)
Site
SFSD
SIAL
SJPR
SKFL
SMFL
SPIL
SYFL
TOOK
TRTX
TSOK
TUMS
TUOK
UNVT
Monitoring Period"
Starting
Date
1/5/06
1/11/06
1/5/06
1/5/06
1/5/06
1/5/06
1/5/06
1/23/06
1/5/06
6/10/06
1/5/06
1/23/06
1/5/06
Ending
Date
12/31/06
7/4/06
12/31/06
12/31/06
12/31/06
12/31/06
12/31/06
12/31/06
6/28/06
12/31/06
12/31/06
12/31/06
12/31/06
Carbonyl
A
60
16
40
60
61
60
61
44
16
28
61
30
B
61
16
52
60
61
62
61
52
18
32
61
54
C
98
100
77
100
100
97
100
85
89
88
100
56
voc
A
59
18
40
61
44
16
29
60
31
B
61
18
52
61
53
18
32
61
55
C
97
100
77
100
83
89
91
98
56
Hexavalent
Chromium
A
16
57
59
B
16
59
61
C
100
97
97
Metals
A
15
14
15
15
13
B
15
14
16
15
13
C
100
100
94
100
100
SNMOC
A
59
16
B
61
18
C
97
89
svoc
A
16
B
18
C
89
to
-k
VO
a Begins with 1st valid sample and may include all six analyses.
A = Valid Samples
B = Total Number of Samples
C = Completeness (%)
-------
Table 2-10. Sampling Schedules and Completeness (Continued)
Site
WADC
WETX
WPIN
YDSP
Monitoring Period"
Starting
Date
1/5/06
1/5/06
6/28/06
1/5/06
Ending
Date
12/31/06
6/28/06
12/31/06
3/14/06
Overall
Carbonyl
A
14
5
1,839
B
17
6
1,923
C
82
83
96
voc
A
15
17
1,329
B
18
19
1,441
C
83
89
92
Hexavalent
Chromium
A
59
12
1,000
B
61
16
1,035
C
97
75
97
Metals
A
17
529
B
17
539
C
100
98
SNMOC
A
15
375
B
17
395
C
88
95
svoc
A
183
B
194
C
94
a Begins with 1st valid sample and may include all six analyses.
A = Valid Samples
B = Total Number of Samples
C = Completeness (%)
-------
According to the UATMP schedule, 24-hour integrated samples were to be collected at
every monitoring site approximately l-in-6 or l-in-12 days (dependent upon location) and each
sample collection began and ended at midnight, local standard time. Table 2-10 shows the
following:
• At most sites, VOC and carbonyl samples were collected concurrently.
• Of the 59 sites, 12 did not sample for VOC and/or carbonyls.
• Six sites sampled SVOCs.
• 10 sites collected SNMOC or TNMOC samples.
• 20 sites collected metal samples.
• Finally, 23 sites collected hexavalent chromium samples.
As part of the sampling schedule, site operators were instructed to collect duplicate
samples on roughly 10 percent of the sampling days for select methods when duplicate samplers
were available. Sampling calendars were distributed to help site operators schedule the
collection of samples, duplicates, and field blanks. Field blanks were collected once a month for
carbonyl compounds, hexavalent chromium, metals, and SVOC. In cases where monitors failed
to collect valid samples on a scheduled sampling day, site operators were instructed to
reschedule samples for other days. This practice explains why some monitoring locations
periodically strayed from the l-in-6 or l-in-12 day sampling schedule. The State of Michigan
prepared a schedule that allowed Michigan's Department of Environmental Quality's laboratory
to share samples with ERG's laboratory.
The l-in-6 or l-in-12 day sampling schedule provides cost-effective approaches to data
collection for trends characterization (annual average concentrations) of toxic pollutants in
ambient air and ensures that sampling days are evenly distributed among the seven days of the
week to allow weekday/weekend comparison of air quality. Because the l-in-6 day schedule
yields twice the number of measurements, data characterization based on this schedule tends to
be more robust.
2-51
-------
The post-Katrina monitoring site in Gulfport, MS (GPMS) followed a sampling schedule
that was different from other UATMP sites. GPMS followed a l-in-3 day sampling schedule
from January through March, and then decreased its sampling frequency to a l-in-6 day
frequency for the remainder of the year.
2.4 Completeness
Completeness refers to the number of valid samples collected and analyzed compared to
the number of total samples attempted. Monitoring programs that consistently generate valid
results have higher completeness than programs that consistently invalidate samples. The
completeness of an air monitoring program, therefore, can be a qualitative measure of the
reliability of air sampling equipment and laboratory analytical equipment and a measure of the
efficiency with which the program was managed. Appendix B identifies samples that were
invalidated and lists the specific reasons why the samples were invalidated.
Table 2-10 summarizes the completeness of the monitoring data sets collected during the
2006 UATMP:
• For VOC sampling, the completeness ranged from 56 to 100 percent, with an overall
completeness of 92 percent;
• For carbonyl sampling, the completeness ranged from 56 to 100 percent with an
overall completeness of 96 percent;
• For SNMOC sampling, the completeness ranged from 83 to 98 percent with an
overall completeness of 95 percent;
• For SVOC sampling, the completeness ranged from 83 to 97 percent with an overall
completeness of 94 percent;
• For metals sampling, the completeness ranged from 81 to 100 percent with an overall
completeness was 98 percent; and
• For hexavalent chromium sampling, the completeness ranged from 75 to 100 percent,
with an overall completeness was 97 percent.
2-52
-------
The UATMP data quality objective for completeness based on the EPA-approved Quality
Assurance Project Plan (QAPP), specifies that 85-100 percent of samples collected at a given
monitoring site must be analyzed successfully to be considered sufficient for data trends analysis
(ERG, 2006/2007). The data in Table 2-10 shows that 14 data sets (from a total of 139 data sets)
for the 2006 UATMP monitoring sites did not meet this data quality objective. These data sets
were lower than the 85 percent criteria for a number of reasons. A few sites did not meet the
objective because there were complications at the onset of sampling (TOOK, TSOK, TUOK, and
IDIN). Other sites were having sampling issues that would not allow make-up samples to be
performed (PVAL, SEW A, RRTX, WETX and SJPR). One hundred percent completeness was
achieved for 22 carbonyl monitoring sites, five VOC monitoring sites, seven hexavalent
chromium monitoring sites, and 17 metals monitoring sites.
2-53
-------
3.0 Summary of the 2006 UATMP Data
This section summarizes the data gathered during the 2006 UATMP reporting year. A
total of 182,974 valid urban air toxics concentrations (including non-detect, duplicate analyses,
replicate analyses, and analyses for collocated samples) were collected at 59 sites for the 2006
UATMP reporting year. These data were analyzed on a site-specific basis and results are
presented in the individual state sections, Sections 4.0 through 31.0. A tabular presentation of
the summary and raw data is found in Appendices C through O, as follows:
Pollutant
voc
SNMOC
Carbonyl
svoc
Metals
Hexavalent Chromium
TNMOC
Range of Detection Limits
# Sites
34
5
45
6
20
23
5
—
Appendix
Summary Data
C
D
E
F
G
H
D
O
Raw Data
I
J
K
L
M
N
J
—
Sites sampling in Texas and Alabama were commissioned to sample for one year,
beginning in the summer of 2005 and continuing through the summer of 2006, though the start
and end dates vary slightly from site to site. In order to facilitate data analysis, the entire dataset
for the one year sampling duration for sites in Texas and Alabama is included in the individual
state sections' analyses (Section 4.0 for Alabama; Section 27.0 for Texas). However, for the
data analyses presented in Section 3.0 and Section 32.0 (Quality Assurance), only 2006 data
were considered.
3.1 Data Summary Parameters
The raw data tables in Appendices I through N were uploaded into a database for air
quality statistical analysis. This section examines six different data summary parameters and
reviews the basic findings determined from the statistical analysis: 1) number of measured
detections, 2) concentration ranges, 3) central tendency statistics, 4) risk screening, 5) non-
chronic risk, and 6) correlation. The six analyses described in Section 3.1 were completed on the
program-level UATMP data set and the data set for each state. Results of the program-level data
5-1
-------
set analyses are described here in Section 3.1. Results for analyses completed as the site-specific
data set are presented in the state-specific sections.
To better understand the following sections, it is important to know how the
concentration data were treated. First, all duplicate and replicate (or collocated) measurements
were averaged in order to calculate a single concentration for each pollutant for each sampling
day at each site. Second, m,p-xy\ene and o-xylene concentrations were summed together and are
henceforth referred to as "total xylenes," "xylenes (total)," or simply "xylenes" throughout the
remainder of this report, with the exception of Table 3-1 and Table 3-4, as well as Section 32.0,
where results are broken into m,p-xy\Qne and o-xylene species. This is referred to as the
preprocessed daily measurement.
In order to compare concentrations across multiple sampling methods, all concentrations
have been converted to a common unit of measure: |ig/m3. However, whenever a particular
sampling method is isolated from others, such as in Tables 3-1 through 3-6, the statistical
parameters are presented in the units of measure associated with the particular sampling method.
It is important to pay very close attention to the unit of measure associated with each analysis
discussed in this section of the report.
3.1.1 Target Pollutant Detections
Tables 3-1 through 3-6 summarize the number of times the target pollutants were
detected out of the number of valid samples taken. Approximately 51 percent of the pollutants
sampled were measured above the MDLs. The percentages listed below represent the percent of
measurements that were above the MDLs:
• 44.3 percent of VOC;
• 85.7 percent of carbonyl compounds;
• 45.7 percent of SNMOC;
5-2
-------
Table 3-1. Statistical Summaries of the VOC Concentrations
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Tetrachloride
Carbon Bisulfide
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1,2-Dibromoethane
/w-Dichlorobenzene
o-Dichlorobenzene
£>-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
#of
Measured
Detections"
896
1,326
1,048
70
12
1,329
0
42
o
6
1,208
1,132
1,326
1,018
65
842
934
1,329
8
17
39
1
29
15
987
1,329
0
30
8
34
8
Minimum
(ppbv)
0.06
0.01
0.05
0.02
0.01
0.05
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.15
0.01
0.01
0.01
0.01
0.01
0.01
0.11
0.01
0.03
0.04
0.01
Maximum
(ppbv)
502.25
39.70
5.37
2.06
0.22
9.87
0.09
0.01
31.10
1.36
0.22
78.80
0.10
0.48
2.40
4.72
0.07
0.12
0.03
0.09
0.06
3.75
1.17
0.85
0.17
0.34
0.08
Arithmetic
Mean
(ppbv)
6.14
0.94
0.41
0.21
0.04
0.37
0.03
0.01
0.04
0.05
0.10
2.09
0.03
0.02
0.05
0.62
0.03
0.03
0.01
0.02
0.02
0.05
0.54
0.05
0.09
0.13
0.02
Mode
(ppbv)
0.43
0.45
0.16
0.05
0.01
0.20
0.03
0.01
0.01
0.02
0.10
0.02
0.02
0.01
0.02
0.58
0.01
0.03
0.01
0.01
0.01
0.01
0.54
0.01
0.11
0.08
0.01
Median
(ppbv)
0.95
0.61
0.27
0.13
0.03
0.27
N
0.03
0.01
0.01
0.04
0.10
0.73
0.03
0.02
0.02
0.59
0.02
0.03
0.01
N
0.01
0.01
0.02
0.54
N
0.02
0.10
0.11
0.01
Geometric
Mean
(ppbv)
1.20
0.65
0.30
0.14
0.02
0.28
A
0.03
0.01
0.01
0.04
0.10
0.48
0.03
0.02
0.03
0.59
0.02
0.03
0.01
A
0.02
0.01
0.02
0.53
A
0.02
0.08
0.12
0.02
First
Quartile
(ppbv)
0.37
0.39
0.18
0.09
0.01
0.18
0.02
0.01
0.01
0.02
0.08
0.07
0.02
0.01
0.02
0.51
0.01
0.02
0.01
0.01
0.01
0.01
0.49
0.01
0.05
0.08
0.01
Third
Quartile
(ppbv)
3.19
1.04
0.47
0.27
0.03
0.42
0.03
0.01
0.02
0.07
0.12
2.34
0.04
0.02
0.04
0.67
0.03
0.04
0.01
0.02
0.03
0.04
0.58
0.02
0.12
0.17
0.02
Standard
Deviation
(ppbv)
25.53
1.50
0.45
0.26
0.06
0.45
0.02
<0.01
0.89
0.06
0.03
4.33
0.02
0.03
0.11
0.22
0.02
0.03
<0.01
0.02
0.01
0.20
0.09
0.15
0.05
0.07
0.02
Coefficient
of
Variation
4.16
.60
.11
.25
.37
.21
0.59
<0.01
20.66
1.16
0.31
2.07
0.61
1.38
2.18
0.35
0.70
0.77
0.34
0.95
0.78
4.24
0.17
3.25
0.51
0.50
1.08
a Number of measured detections out of 1,329 valid samples.
-------
Table 3-1. Statistical Summaries of the VOC Concentrations (Continued)
Pollutant
Dichloromethane
1,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl tert-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tert-Butyl Ether
w-Octane
Propylene
Styrene
1, 1,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
1,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1, 1,2-Trichloroethane
Trichloroethylene
Trichlorofluoromethane
Trichlorotrifluoroethane
1,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Vinyl chloride
m,p-Xylene
o-Xylene
#of
Measured
Detections"
1,288
3
0
0
1,324
4
16
1,326
86
1,274
989
26
275
1,130
1,329
1,149
16
947
1,329
43
1,313
4
407
1,327
1,329
1,265
1,186
145
1,329
1,321
Minimum
(ppbv)
0.02
0.01
Maximum
(ppbv)
44.33
0.01
Arithmetic
Mean
(ppbv)
0.29
0.01
Mode
(ppbv)
0.06
0.01
Median
(ppbv)
0.09
0.01
Geometric
Mean
(ppbv)
0.11
0.01
First
Quartile
(ppbv)
0.06
0.01
Third
Quartile
(ppbv)
0.14
0.01
Standard
Deviation
(ppbv)
1.62
0.01
Coefficient
of
Variation
5.49
0.01
NA
NA
0.01
0.01
0.01
0.01
0.01
0.04
0.01
0.01
0.01
0.01
0.04
0.01
0.01
0.01
0.04
0.01
0.01
0.01
0.01
0.01
0.03
0.01
0.01
0.01
0.01
0.01
0.07
0.19
0.27
9.60
0.07
19.10
3.63
5.20
4.20
4.08
13.50
6.70
0.19
1.94
45.00
0.36
0.23
0.02
0.76
1.57
0.47
6.99
1.76
0.63
6.60
2.60
0.02
0.06
0.06
0.12
0.02
0.57
0.09
0.49
0.19
0.06
0.55
0.09
0.03
0.05
0.81
0.03
0.02
0.01
0.05
0.27
0.11
0.11
0.03
0.02
0.29
0.11
0.02
NA
0.01
0.04
0.02
0.28
0.04
0.01
0.04
0.02
0.17
0.02
0.01
0.02
0.21
0.01
0.02
0.01
0.02
0.26
0.10
0.03
0.01
0.01
0.09
0.03
0.02
0.03
0.03
0.07
0.02
0.40
0.05
0.14
0.07
0.03
0.35
0.03
0.01
0.03
0.47
0.02
0.02
0.01
0.03
0.26
0.10
0.06
0.02
0.01
0.16
0.06
0.02
0.03
0.03
0.07
0.02
0.40
0.06
0.14
0.08
0.04
0.37
0.04
0.02
0.03
0.48
0.02
0.02
0.01
0.03
0.27
0.10
0.06
0.02
0.01
0.17
0.07
0.02
0.02
0.01
0.04
0.01
0.25
0.03
0.04
0.04
0.02
0.21
0.02
0.01
0.02
0.25
0.01
0.02
0.01
0.02
0.24
0.09
0.03
0.01
0.01
0.09
0.04
0.02
0.07
0.06
0.12
0.02
0.62
0.09
0.48
0.14
0.05
0.57
0.06
0.02
0.05
0.86
0.03
0.02
0.01
0.04
0.29
0.11
0.12
0.04
0.01
0.31
0.12
0.01
0.07
0.07
0.36
0.01
0.80
0.20
1.05
0.43
0.17
0.92
0.33
0.04
0.10
1.73
0.05
0.01
O.01
0.08
0.07
0.03
0.23
0.06
0.05
0.44
0.15
0.26
1.18
1.32
2.97
0.51
1.40
2.11
2.13
2.32
2.85
1.66
3.77
1.58
1.91
2.14
1.68
0.48
0.35
1.73
0.27
0.32
2.20
1.79
3.32
1.54
1.41
a Number of measured detections out of 1,329 valid samples.
-------
Table 3-2. Statistical Summaries of the Carbonyl Compound Concentrations
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2, 5 -Dimethylbenzaldehy de
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
#of
Measured
Detections"
1,839
1,839
1,825
1,838
1,771
0
1,828
1,803
810
1,834
1,752
1,796
Minimum
(ppbv)
0.05
0.02
0.01
0.01
0.01
Maximum
(ppbv)
15.40
7.20
1.10
3.57
2.77
Arithmetic
Mean
(ppbv)
1.20
0.82
0.05
0.10
0.10
Mode
(ppbv)
1.18
1.10
0.02
0.05
0.03
Median
(ppbv)
0.92
0.63
0.03
0.07
0.05
Geometric
Mean
(ppbv)
0.96
0.60
0.03
0.07
0.05
First
Quartile
(ppbv)
0.63
0.32
0.02
0.05
0.03
Third
Quartile
(ppbv)
1.45
1.10
0.05
0.11
0.10
Standard
Deviation
(ppbv)
0.98
0.72
0.06
0.13
0.15
Coefficient
of
Variation
0.82
0.88
1.33
1.30
1.57
NA
0.02
0.01
0.01
0.01
0.01
0.01
205.00
1.51
0.23
2.15
1.78
0.94
4.07
0.05
0.02
0.12
0.04
0.05
1.33
0.02
0.01
0.08
0.02
0.02
1.94
0.03
0.01
0.09
0.03
0.03
2.03
0.03
0.01
0.09
0.03
0.03
1.21
0.02
0.01
0.06
0.02
0.02
3.07
0.04
0.02
0.14
0.04
0.05
12.96
0.11
0.02
0.11
0.05
0.09
3.18
2.04
1.14
0.94
1.33
1.59
1 Number of measured detections out of 1,839 valid samples.
-------
Table 3-3a. Statistical Summaries of the SVOC (Method TO-13A) Concentrations
Pollutant
Acenaphthene
Acenaphthylene
Anthracene
Benzo (a) anthracene
Benzo (a) pyrene
Benzo (b) fluoranthene
Benzo (e) pyrene
Benzo (g,h,i) perylene
Benzo (k) fluoranthene
Chrysene
Coronene
Dibenz (a,h) anthracene
Fluoranthene
Fluorene
Indeno(l,2,3-cd)pyrene
Naphthalene
Perylene
Phenanthrene
Pyrene
#of
Measured
Detections"
121
107
96
110
93
114
99
107
113
117
81
47
122
122
102
122
54
122
122
Minimum
(ng/m3)
0.04
0.02
0.04
0.02
0.02
0.04
0.02
0.02
0.02
0.03
0.02
0.02
0.08
0.17
0.02
0.13
0.02
0.33
0.04
Maximum
(ng/m3)
32.50
30.10
87.20
21.90
15.30
22.10
13.70
9.21
16.00
25.00
1.90
2.45
73.10
45.60
13.10
1,220.00
3.98
157.00
46.40
Arithmetic
Mean
(ng/m3)
4.51
3.15
3.16
1.12
0.91
1.07
0.85
0.57
0.83
1.56
0.23
0.34
4.87
5.66
0.73
146.46
0.41
15.39
2.86
Mode
(ng/m3)
0.27
1.37
0.20
0.02
0.40
0.08
0.12
0.09
0.11
0.13
0.17
0.02
1.61
21.50
0.08
2.69
0.02
13.40
2.39
Median
(ng/m3)
0.58
0.50
0.66
0.12
0.17
0.17
0.14
0.14
0.12
0.25
0.08
0.08
1.79
1.63
0.16
7.73
0.09
5.79
1.00
Geometric
Mean
(ng/m3)
1.06
0.64
0.74
0.18
0.23
0.24
0.21
0.18
0.17
0.36
0.11
0.12
1.99
2.28
0.20
9.42
0.13
6.40
1.14
First
Quartile
(ng/m3)
0.24
0.14
0.20
0.04
0.07
0.07
0.07
0.06
0.04
0.13
0.05
0.04
0.80
0.81
0.07
0.59
0.04
2.59
0.44
Third
Quartile
(ng/m3)
6.57
3.51
2.99
0.39
0.63
0.51
0.46
0.41
0.39
0.82
0.27
0.54
4.68
7.15
0.39
131.00
0.57
13.63
2.99
Standard
Deviation
(ng/m3)
7.15
5.65
9.62
2.90
2.05
2.69
1.90
1.22
2.03
3.54
0.33
0.51
8.76
8.09
1.68
276.06
0.67
23.63
5.40
Coefficient
of
Variation
1.59
1.79
3.04
2.59
2.25
2.50
2.23
2.13
2.45
2.27
1.42
1.50
1.80
1.43
2.29
1.88
1.62
1.54
1.89
1 Number of measured detections out of 122 valid samples.
-------
Table 3-3b. Statistical Summaries of the SVOC (Method 8270C) Concentrations
Pollutant
Acenaphthene
Acenaphthylene
Acetophenone
2-Acetylaminofluorene
4-Aminobiphenyl
Aniline
Anthracene
Azobenzene
Benzidine
Benzo (a) anthracene
Benzo (a) pyrene
Benzo (b) fluoranthene
Benzo (g,h,i) perylene
Benzo (k) fluoranthene
Benzyl alcohol
Bis(2-chloroethoxy)methane
Bis(2-chloroethyl)ether
Bis(2-chloroisopropyl)ether
Bis(2-ethylhexyl)phthalate
4-Bromophenyl phenyl ether
Butyl benzyl phthalate
Carbazole
4-Chloro-3-methylphenol
4-Chloroaniline
Chlorobenzilate
2-Chloronaphthalene
2-Chlorophenol
4-Chlorophenyl phenyl ether
#of
Measured
Detections"
59
7
56
0
0
0
9
0
0
7
0
0
0
0
0
0
0
0
56
0
17
0
0
0
0
0
0
0
Arithmetic
Minimum Maximum Mean Mode Median
Gig/m3) (jig/m3) (ug/m3) frig/m3) &ig/m3)
0.001 0.025 0.007 NA 0.006
0.001 0.004 0.002 NA 0.002
0.004 0.044 0.011 0.013 0.009
Geometric First Th
Mean Quartile Qua
(jig/m3) (jig/m3) Qig/
0.006 0.003 0.0
0.002 0.001 0.0
0.010 0.006 0.0
NA
ird Standard Coefficient
rtile Deviation of
m3) Gig/m3) Variation
09 0.006 0.795
02 0.001 0.506
12 0.008 0.694
NA
NA
O.001 0.021 0.008 NA 0.005
0.003 0.001 0.0
NA
11 0.008 1.028
NA
0.001 0.001 0.001 NA 0.001
0.001 0.001 0.0
NA
01 0.001 0.314
NA
NA
NA
NA
NA
NA
NA
0.002 0.037 0.007 0.002 0.005
0.006 0.004 0.0
NA
0.001 0.004 0.001 0.001 0.001
0.001 0.001 0.0
NA
09 0.007 0.878
02 0.001 0.484
NA
NA
NA
NA
NA
NA
a Number of measured detections out of 60 valid samples.
-------
Table 3-3b. Statistical Summaries of the SVOC (Method 8270C) Concentrations (Continued)
Pollutant
Chrysene
Diallate
Dibenz (a,h) anthracene
Dibenzofuran
1 ,2-Dichlorobenzene
1 ,3 -Dichlorobenzene
1 ,4-Dichlorobenzene
3,3 '-Dichlorobenzidine
2,4-Dichlorophenol
2,6-Dichlorophenol
Diethyl phthalate
Dimethyl phthalate
4-Dimethylaminoazobenzene
7,12-Dimethylbenz (a)
anthracene
3,3 '-Dimethylbenzidine
2,4-Dimethylphenol
Di-n-butyl phthalate
4,6-Dinitro-2-methylphenol
1 ,3 -Dinitrobenzene
2,4-Dinitrophenol
2,4-Dinitrotoluene
2,6-Dinitrotoluene
Di-n-octyl phthalate
Dinoseb
Diphenylamine
Ethyl Methanesulfonate
Fluoranthene
Fluorene
#of
Measured
Detections"
7
0
0
61
0
0
56
0
0
0
58
0
0
0
0
0
43
0
0
0
0
0
4
0
0
0
56
60
Minimum
(Hg/m3)
O.001
Maximum
(Hg/m3)
0.001
Arithmetic
Mean
(Hg/m3)
<0.001
Mode
(Hg/m3)
NA
Median
(Hg/m3)
O.001
Geometric
Mean
(Hg/m3)
O.001
First
Quartile
(Hg/m3)
O.001
Third
Quartile
(Hg/m3)
0.001
Standard
Deviation
(Hg/m3)
<0.001
Coefficient
of
Variation
0.720
NA
NA
0.002
0.021
0.008
0.002
0.006
0.007
0.005
0.010
0.004
0.563
NA
NA
0.002
0.118
0.028
0.022
0.016
0.017
0.009
0.039
0.027
0.989
NA
NA
NA
0.001
0.017
0.004
0.003
0.003
0.003
0.002
0.004
0.002
0.613
NA
NA
NA
NA
NA
0.001
0.050
0.004
0.002
0.002
0.003
0.002
0.003
0.008
1.878
NA
NA
NA
NA
NA
0.009
0.011
0.009
NA
0.009
0.009
0.009
0.009
0.001
0.083
NA
NA
NA
0.001
0.002
0.004
0.017
0.002
0.006
0.003
0.011
0.002
0.005
0.002
0.005
0.001
0.003
0.002
0.008
0.001
0.003
0.420
0.581
a Number of measured detections out of 60 valid samples.
-------
Table 3-3b. Statistical Summaries of the SVOC (Method 8270C) Concentrations (Continued)
Pollutant
Hexachlorobenzene
Hexachlorobutadiene
Hexachlorocyclopentadiene
Hexachloroethane
Hexachloropropene
Indeno( 1,2,3 -cd)py rene
Isodrin
Isophorone
Isosafrole
Methyl Methanesulfonate
3 -Methy Icholanthrene
2-Methylnaphthalene
2-Methylphenol
3 & 4-Methylphenol
Naphthalene
1 ,4-Naphthoquinone
1-Naphthylamine
2-Naphthylamine
2-Nitroaniline
3-Nitroaniline
4-Nitroaniline
Nitrobenzene
5-Nitro-o-toluidine
2-Nitrophenol
4-Nitrophenol
N-Nitrosodiethylamine
N-Nitrosodimethylamine
N-Nitrosodi-n-butylamine
N-Nitrosodi-n-propylamine
#of
Measured
Detections"
0
0
0
0
0
0
0
0
0
0
0
61
4
8
60
0
0
0
0
0
0
0
0
10
0
0
0
0
0
Arithmetic
Minimum Maximum Mean Mode Median
Gig/m3) (jig/m3) (jig/m3) (jig/m3) (jig/m3)
Geometric First Th
Mean Quartile Qua
Gig/m3) (jig/m3) (jig/
NA
ird Standard Coefficient
rtile Deviation of
m3) (fig/m3) Variation
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
0.006 0.070 0.027 0.018 0.024
0.001 0.005 0.003 NA 0.004
0.003 0.016 0.008 NA 0.006
0.008 0.125 0.049 0.064 0.044
0.023 0.016 0.0
0.003 0.002 0.0
0.007 0.004 0.0
0.042 0.028 0.0
NA
35 0.013 0.499
05 0.001 0.405
12 0.004 0.546
61 0.027 0.546
NA
NA
NA
NA
NA
NA
NA
0.003 0.018 0.010 NA 0.010
0.009 0.007 0.0
NA
11 0.004 0.418
NA
NA
NA
NA
a Number of measured detections out of 60 valid samples.
-------
Table 3-3b. Statistical Summaries of the SVOC (Method 8270C) Concentrations (Continued)
Pollutant
N-Nitrosomethylethylamine
N-Nitrosopiperidine
N-Nitrosopyrrolidine
Pentachlorobenzene
Pentachloroethane
Pentachloronitrobenzene
Pentachlorophenol
Phenacetin
Phenanthrene
Phenol
2-Picoline
Pronamide
Pyrene
Pyridine
Safrole
1,2,4,5-Tetrachlorobenzene
2,3 ,4,6-Tetrachlorophenol
o-Toluidine
1 ,2,4-Trichlorobenzene
2,4,5-Trichlorophenol
2,4,6-Trichlorophenol
#of
Measured
Detections"
0
0
0
0
0
0
5
0
61
18
0
0
48
0
0
0
0
0
0
0
0
Arithmetic
Minimum Maximum Mean Mode Median
Gig/m3) (jig/m3) (jig/m3) (jig/m3) (jig/m3)
Geometric First Th
Mean Quartile Qua
Gig/m3) (jig/m3) (jig/
NA
ird Standard Coefficient
rtile Deviation of
m3) (fig/m3) Variation
NA
NA
NA
NA
NA
0.001 0.004 0.003 NA 0.002
0.002 0.001 0.0
NA
0.003 0.028 0.011 0.014 0.010
0.003 0.013 0.007 NA 0.005
0.010 0.006 0.0
0.006 0.004 0.0
NA
04 0.001 0.566
14 0.006 0.509
09 0.003 0.494
NA
0.001 0.002 0.001 0.001 0.001
0.001 0.001 0.0
NA
02 0.001 0.351
NA
NA
NA
NA
NA
NA
NA
1 Number of measured detections out of 60 valid samples.
-------
Table 3-4. Statistical Summaries of the SNMOC Concentrations
Pollutant
Acetylene
Benzene
1,3 -Butadiene
w-Butane
c/s-2-Butene
/ra«s-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
w-Decane
1-Decene
/w-Diethylbenzene
£>-Diethylbenzene
2,2-Dimethylbutane
2,3 -Dimethylbutane
2,3 -Dimethylpentane
2,4-Dimethylpentane
w-Dodecane
1-Dodecene
Ethane
2-Ethyl-l-butene
Ethylbenzene
Ethylene
/w-Ethyltoluene
o-Ethyltoluene
£>-Ethyltoluene
w-Heptane
1-Heptene
#of
Measured
Detections"
298
298
117
298
237
233
275
281
54
246
0
142
142
285
289
278
274
165
111
298
0
297
296
281
198
271
297
218
Minimum
(ppbC)
0.29
0.20
0.03
0.54
0.03
0.03
0.03
0.05
0.05
0.06
Maximum
(ppbC)
43.35
19.40
7.70
98.00
2.34
5.67
5.72
325.25
1.47
16.30
Arithmetic
Mean
(ppbC)
2.35
1.43
0.24
6.09
0.27
0.31
0.50
1.53
0.29
0.68
Mode
(ppbC)
1.09
1.03
0.12
1.33
0.10
0.32
0.16
0.11
0.13
0.25
Median
(ppbC)
1.64
1.13
0.14
3.85
0.22
0.21
0.33
0.27
0.22
0.34
Geometric
Mean
(ppbC)
1.76
1.19
0.15
4.07
0.21
0.23
0.33
0.28
0.23
0.38
First
Quartile
(ppbC)
1.10
0.78
0.10
2.26
0.13
0.14
0.19
0.16
0.14
0.24
Third
Quartile
(ppbC)
2.62
1.69
0.24
7.31
0.32
0.36
0.58
0.45
0.35
0.54
Standard
Deviation
(ppbC)
3.08
1.34
0.70
7.90
0.23
0.42
0.61
19.35
0.24
1.53
Coefficient
of
Variation
1.31
0.94
2.96
1.30
0.89
1.35
1.22
12.64
0.82
2.26
NA
0.05
0.04
0.07
0.04
0.10
0.05
0.02
0.04
1.04
4.34
2.37
8.40
6.92
4.74
3.00
14.50
2.66
52.80
0.60
0.35
0.41
0.51
0.60
0.39
0.52
0.49
8.38
0.15
0.07
0.38
0.26
0.58
0.44
0.20
0.14
4.08
0.36
0.21
0.34
0.39
0.41
0.30
0.22
0.33
6.39
0.37
0.23
0.32
0.38
0.44
0.30
0.25
0.33
6.84
0.18
0.12
0.21
0.23
0.26
0.17
0.15
0.17
4.71
0.72
0.42
0.49
0.60
0.73
0.44
0.35
0.61
9.34
0.70
0.37
0.60
0.54
0.58
0.36
1.45
0.47
6.66
1.16
1.05
1.46
1.06
0.97
0.92
2.80
0.96
0.79
NA
0.04
0.25
0.03
0.05
0.03
0.07
0.05
8.54
50.20
24.40
10.70
11.70
4.22
1.44
0.74
3.01
0.60
0.40
0.34
0.59
0.22
0.53
1.24
0.44
0.21
0.16
1.21
0.11
0.54
2.11
0.44
0.25
0.24
0.40
0.16
0.53
2.32
0.41
0.26
0.25
0.44
0.18
0.30
1.56
0.24
0.16
0.16
0.25
0.13
0.90
3.63
0.66
0.35
0.36
0.71
0.25
0.79
3.57
1.49
0.88
0.74
0.53
0.17
1.06
1.18
2.50
2.21
2.17
0.90
0.79
1 Number of measured detections out of 298 valid samples.
-------
Table 3-4. Statistical Summaries of the SNMOC Concentrations (Continued)
Pollutant
w-Hexane
1-Hexene
c/s-2-Hexene
/raws-2-Hexene
Isobutane
Isobutene/ 1 -Butene
Isopentane
Isoprene
Isopropylbenzene
2-Methyl-l-butene
3 -Methyl- 1 -butene
2-Methyl-l-pentene
4-Methyl- 1 -pentene
2-Methyl-2 -butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2-Methylhexane
3 -Methy Ihexane
2-Methylpentane
3-Methylpentane
w-Nonane
1-Nonene
w-Octane
1-Octene
w-Pentane
1 -Pentene
c/s-2-Pentene
#of
Measured
Detections"
297
258
13
24
297
294
285
254
136
233
11
32
10
222
296
296
271
232
262
297
286
297
280
168
295
132
298
275
202
Minimum
(ppbC)
0.14
0.05
0.03
0.05
0.19
0.15
0.23
0.02
0.03
0.05
0.10
0.03
0.18
0.04
0.07
0.06
0.03
0.04
0.05
0.11
0.12
0.12
0.08
0.04
0.07
0.05
0.34
0.09
0.03
Maximum
(ppbC)
49.80
1.83
2.20
1.47
115.75
24.20
672.00
13.60
1.24
8.54
0.77
1.29
0.59
1.74
5.19
21.95
2.31
2.11
6.25
13.70
30.90
25.08
6.32
2.53
5.77
1.33
3,042.50
78.90
2.30
Arithmetic
Mean
(ppbC)
1.48
0.28
0.32
0.19
4.35
1.33
8.40
0.89
0.15
0.63
0.28
0.12
0.33
0.30
0.67
0.84
0.32
0.24
0.69
1.48
2.71
1.06
0.35
0.26
0.41
0.28
15.81
0.92
0.20
Mode
(ppbC)
2.56
0.11
NA
0.13
1.26
1.22
12.70
0.29
0.10
0.14
0.10
0.03
NA
0.12
0.23
1.28
0.13
0.15
1.05
1.20
1.50
1.48
0.25
0.11
0.19
0.10
2.38
1.02
0.21
Median
(ppbC)
0.80
0.24
0.13
0.12
1.94
0.91
3.86
0.39
0.13
0.44
0.16
0.07
0.29
0.22
0.43
0.57
0.26
0.19
0.54
1.22
1.93
0.73
0.25
0.19
0.31
0.20
2.73
0.34
0.18
Geometric
Mean
(ppbC)
0.92
0.23
0.15
0.13
2.34
0.96
4.22
0.46
0.13
0.39
0.21
0.07
0.31
0.23
0.47
0.57
0.26
0.19
0.48
1.12
1.81
0.77
0.27
0.19
0.32
0.21
2.94
0.38
0.17
First
Quartile
(ppbC)
0.48
0.14
0.06
0.09
1.18
0.67
2.31
0.21
0.10
0.16
0.11
0.05
0.22
0.14
0.29
0.32
0.16
0.13
0.26
0.71
0.97
0.52
0.17
0.12
0.20
0.13
1.52
0.20
0.12
Third
Quartile
(ppbC)
1.66
0.35
0.23
0.15
4.12
1.26
7.73
0.96
0.16
0.89
0.43
0.10
0.39
0.40
0.77
0.96
0.39
0.29
0.84
1.80
3.46
1.17
0.40
0.28
0.47
0.34
5.22
0.59
0.24
Standard
Deviation
(ppbC)
3.11
0.21
0.56
0.28
8.40
1.95
39.84
1.39
0.14
0.79
0.22
0.22
0.14
0.23
0.69
1.40
0.26
0.20
0.70
1.36
3.32
1.68
0.48
0.30
0.45
0.24
177.04
4.85
0.18
Coefficient
of
Variation
2.11
0.75
1.74
1.47
1.93
1.46
4.74
1.56
0.90
1.25
0.79
1.87
0.41
0.78
1.04
1.68
0.81
0.85
1.02
0.92
.22
.58
.37
.16
.08
0.85
11.20
5.26
0.89
1 Number of measured detections out of 298 valid samples.
-------
Table 3-4. Statistical Summaries of the SNMOC Concentrations (Continued)
Pollutant
/ra«s-2-Pentene
a-Pinene
6-Pinene
Propane
w-Propylbenzene
Propylene
Propyne
Styrene
Toluene
w-Tridecane
1-Tridecene
1 ,2,3 -Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 ,3 ,5-Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3 ,4-Trimethylpentane
w-Undecane
1-Undecene
wj-Xylene/^-Xylene
o-Xylene
SNMOC (Sum of Knowns)
Sum of Unknowns
TNMOC
#of
Measured
Detections"
249
230
29
298
231
298
0
176
298
39
0
224
279
230
141
298
267
220
118
296
296
298
298
298
Minimum
(ppbC)
0.05
0.05
0.03
1.04
0.04
0.27
Maximum
(ppbC)
5.13
14.85
2.90
637.00
6.88
19.30
Arithmetic
Mean
(ppbC)
0.30
1.35
0.82
15.27
0.27
1.39
Mode
(ppbC)
0.15
0.20
NA
17.90
0.13
1.29
Median
(ppbC)
0.24
0.60
0.58
8.75
0.21
1.00
Geometric
Mean
(ppbC)
0.24
0.68
0.49
9.14
0.21
1.10
First
Quartile
(ppbC)
0.17
0.28
0.17
5.09
0.14
0.69
Third
Quartile
(ppbC)
0.35
1.62
1.56
15.02
0.29
1.64
Standard
Deviation
(ppbC)
0.35
1.98
0.72
40.24
0.47
1.48
Coefficient
of
Variation
1.18
1.47
0.87
2.64
1.73
1.06
NA
0.03
0.30
0.05
9.57
60.25
6.92
0.79
3.34
0.48
0.15
1.80
0.09
0.33
2.36
0.16
0.41
2.37
0.21
0.17
1.35
0.10
0.90
4.22
0.29
1.32
4.34
1.12
1.66
1.30
2.32
NA
0.04
0.09
0.04
0.06
0.11
0.04
0.03
0.03
0.14
0.04
14.20
4.50
27.40
6.04
41.10
12.80
2.84
11.03
4.42
26.50
1.64
25.23
10.57
5,002.50
858.00
5,275.00
0.34
0.95
0.37
0.30
0.94
0.41
0.91
0.31
1.65
0.60
100.85
72.34
172.44
0.14
0.11
0.10
0.12
1.01
0.11
0.19
0.08
1.96
0.30
103.00
119.00
118.00
0.23
0.62
0.21
0.23
0.65
0.32
0.39
0.21
1.32
0.46
64.90
52.55
136.00
0.24
0.58
0.23
0.23
0.65
0.31
0.44
0.22
NA
NA
69.33
52.37
132.08
0.14
0.34
0.14
0.13
0.34
0.19
0.24
0.12
0.73
0.28
44.43
30.80
90.93
0.39
0.95
0.35
0.38
1.04
0.49
0.70
0.43
2.02
0.71
100.73
91.80
186.00
0.50
2.61
0.92
0.29
1.05
0.40
2.46
0.29
1.98
0.73
294.64
74.51
317.17
1.46
2.76
2.49
0.97
1.13
0.97
2.70
0.93
1.20
1.22
2.92
1.03
1.84
1 Number of measured detections out of 298 valid samples.
-------
Table 3-5. Statistical Summaries of the Metals Concentrations
Pollutant
Antimony (PM10)
Arsenic (PM10)
Beryllium (PM10)
Cadmium (PM10)
Chromium (PMi0)
Cobalt (PM10)
Lead (PM10)
Manganese (PM10)
Mercury (PM10)
Nickel (PM10)
Selenium (PM10)
Antimony (TSP)
Arsenic (TSP)
Beryllium (TSP)
Cadmium (TSP)
Chromium (TSP)
Cobalt (TSP)
Lead (TSP)
Manganese (TSP)
Mercury (TSP)
Nickel (TSP)
Selenium (TSP)
#of
Measured
Detections3'11
415
415
370
415
415
415
415
415
362
415
413
114
114
114
114
114
114
114
114
98
114
114
Minimum
(ng/m3)
0.02
0.03
0.00
0.00
0.83
0.01
0.08
0.24
0.00
0.26
0.01
0.07
0.08
0.00
0.04
1.20
0.01
1.16
0.85
0.00
0.44
0.08
Maximum
(ng/m3)
11.50
6.83
0.07
15.30
6.50
29.20
60.25
89.10
2.94
7.42
3.95
5.32
21.90
1.23
1.48
13.30
2.36
61.30
614.00
0.69
13.50
7.31
Arithmetic
Mean
(ng/m3)
1.36
0.82
0.01
0.35
2.48
0.30
5.98
10.13
0.07
1.34
0.69
1.19
1.67
0.06
0.31
3.73
0.36
12.49
47.89
0.07
1.73
1.06
Mode
(ng/m3)
1.14
0.39
0.01
0.05
2.00
0.09
3.36
10.60
0.05
1.04
0.20
1.47
2.36
0.01
0.16
2.33
0.20
12.50
22.20
0.01
1.73
0.26
Median
(ng/m3)
0.95
0.59
0.01
0.16
2.25
0.13
3.81
6.29
0.03
1.17
0.49
0.95
0.81
0.01
0.23
3.13
0.26
6.41
23.98
0.03
1.45
0.73
Geometric
Mean
(ng/m3)
0.99
0.61
0.01
0.17
2.34
0.14
4.06
6.68
0.03
1.19
0.47
0.90
0.93
0.02
0.22
3.29
0.23
7.51
22.39
0.03
1.41
0.73
First
Quartile
(ng/m3)
0.64
0.39
0.00
0.09
1.85
0.09
2.28
3.47
0.01
0.89
0.24
0.59
0.51
0.01
0.12
2.38
0.13
3.49
9.10
0.01
0.93
0.40
Third
Quartile
(ng/m3)
1.50
0.96
0.01
0.35
2.90
0.22
6.42
11.80
0.07
1.50
0.87
1.50
1.50
0.03
0.37
4.70
0.42
13.90
46.90
0.07
1.96
1.30
Standard
Deviation
(ng/m3)
1.36
0.79
0.01
0.96
0.92
1.65
6.94
12.01
0.19
0.78
0.64
0.89
2.82
0.17
0.30
2.06
0.39
14.04
82.49
0.11
1.59
1.09
Coefficient
of
Variation
1.00
0.96
0.95
2.70
0.37
5.52
1.16
1.19
2.73
0.58
0.93
0.75
1.69
2.98
0.95
0.55
1.11
1.12
1.72
1.56
0.92
1.03
a For PMi o number of measured detections out of 415 valid samples.
b For TSP number of measured detections out of 114 valid samples.
-------
Table 3-6. Statistical Summaries of the Hexavalent Chromium Concentrations
Pollutant
Hexavalent Chromium
#of
Measured
Detections"
775
Minimum
(ng/m3)
0.001
Maximum
(ng/m3)
0.989
Arithmetic
Mean
(ng/m3)
0.049
Mode
(ng/m3)
0.022
Median
(ng/m3)
0.030
Geometric
Mean
(ng/m )
0.032
First
Quartile
(ng/m3)
0.018
Third
Quartile
(ng/m3)
0.055
Standard
Deviation
(ng/m3)
0.072
Coefficient
of
Variation
1.466
a Number of measured detections out of 1,000 valid samples.
-------
• 83.4 percent of metals;
• 6.0 percent of SVOC; and
• 66.6 percent of hexavalent chromium.
Similar to previous years, acetaldehyde and acetone had the greatest number of measured
detections (1,839) reported in samples taken (1,839). If SVOC measured with Method 8270C
are excluded, nine pollutants (bromochloromethane; 1,1-dichloroethane; c/s-1,3-
dichloropropene; rram--l,3-dichloropropene; 2,5-dimethylbenzaldehyde; 1-decene; 2-ethyl-l-
butene; 1-tridecene; and propyne) had zero measured detections (see Tables 3-1 through 3-6).
The number of pollutants with no measured detections increases dramatically if Method 8270C
pollutants are included (91).
3.1.2 Concentration Range
The concentrations measured during the 2006 UATMP show a wide range of variability,
and the following observations were made in regards to the measured detections.
• Approximately 78 percent of the measured detections had concentration values less
than 1 //g/m3, while less than 3 percent had concentrations greater than 5 jug/m3.
• VOC had the highest number of samples with concentrations greater than 5 jug/m3
(1,153); carbonyl compounds had the least (508); and SVOC, metals, and hexavalent
chromium had no concentrations greater than 5 jug/m3.
• At least one target pollutant had a measurement greater than 5 jug/m3 on 92 of 134
total sampling days.
• Concentrations of 71 target pollutants never exceeded 1 jug/m3.
• Thirteen sites had maximum concentration values over 100 jug/m3.
Excluding GPMS, which was part of the post-Katrina monitoring network and sampled at
a higher frequency compared to other sites, BTUT had the greatest number of measured
detections (6,132, out of a possible 6,437 valid data points), as well as the greatest number of
samples with concentrations greater than 5 jug/m3 (331, out of a possible 6,437 valid data points).
The minimum and maximum concentration measured for each target pollutant is presented in
Tables 3-1 through 3-6 (in respective pollutant group units).
3-16
-------
Eight of the sites that sampled for hexavalent chromium (BTUT, DEMI, HAKY, MVWI,
PRRI, S4MO, SYFL, and WADC) measured their highest concentration on July 4, 2006. The
July 4th hexavalent chromium concentration was one of the five highest concentrations measured
at an additional five sites (BOMA, DHSC, NBIL, SDGA, and UNVT). Hexavalent chromium is
a component in fireworks (NLMa) and it is possible that Independence Day fireworks
celebrations may be leading to this increased concentration level. Additional studies are
recommended (refer to Section 34.0).
3.1.3 Statistics
In addition to the number of measured detections and the concentration ranges,
Tables 3-1 through 3-6 also present a number of central tendency and data distribution statistics
(arithmetic mean, geometric mean, median, mode, first and third quartiles, standard deviation,
and coefficient of variation) for each of the pollutants sampled during the 2006 UATMP by
respective pollutant group units.
The top three VOCs by average mass concentration, as presented in Table 3-1, are
acetonitrile (6.14 ppbv), carbon disulfide (2.09 ppbv), and acetylene (0.94 ppbv). The top three
carbonyl compounds by mass concentration, as presented in Table 3-2, are formaldehyde
(4.07 ppbv), acetaldehyde (1.20 ppbv), and acetone (0.82 ppbv). The top three SVOC by mass
concentration, as presented in Tables 3-3a and 3-3b, are naphthalene (146.46 ng/m3),
phenanthrene (15.39 ng/m3), and fluorene (5.66 ng/m3) as measured with TO-13A method, and
naphthalene (0.049 |ig/m3), 1,4-dichlorobenzene (0.028 |ig/m3), and 2-methylnaphthalene (0.027
|ig/m3) as measured with SW8270/8270C method.
The top three SNMOC by mass concentration, as presented in Table 3-4, are w-pentane
(15.81 ppbC), propane (15.27 ppbC), and isopentane (8.40 ppbC). Among the metals, the top
three pollutants for both PMio and TSP fractions, as presented in Table 3-5, are manganese (TSP
= 47.89 ng/m3, PMi0= 10.13 ng/m3), lead (TSP= 12.49 ng/m3, PMi0= 5.89 ng/m3), and total
chromium (TSP = 3.73 ng/m3, PMio = 2.48 ng/m3). The average mass concentration of
hexavalent chromium, as presented in Table 3-6, is 0.049 ng/m3.
3-17
-------
3.1.4 Risk Screening and Pollutants of Interest
Each year, a subset of pollutants is selected for further analyses. Reviewing a subset of
pollutants is a practical approach if there is a large number of measurements contained in the
dataset. In UATMPs prior to 2003, this subset was based on frequency and magnitude of
concentrations (previously called "prevalent compounds"). Since the 2003 UATMP, risk-based
calculations were used to determine the "pollutants of interest". EPA defines risk as "the
probability that damage to life, health, and/or the environment will occur as a result of a given
hazard (such as exposure to a toxic chemical)" (EPA, 2006c). For the 2006 UATMP, the
pollutants of interest are also based on risk potential.
EPA has published a guidance document outlining a risk screening approach that utilizes
a risk-based methodology for performing an initial screen of ambient air toxics monitoring data
sets (EPA, 2006d). This screening process provides a risk-based methodology for analysts and
interested parties to identify which pollutants may pose a risk in their area. Not all UATMP
pollutants have screening values; those that do are also typically referred to as Hazardous Air
Pollutants (HAPs), as they are known or suspected to cause cancer or other serious health
effects, such as reproductive effects or birth defects, or adverse environmental and ecological
effects. EPA is required to control 188 HAPs (EPA, 2007b). Preprocessed daily measurements
of the target pollutants were compared to risk screening values in order to identify pollutants of
interest across the program. The following risk screening process was completed to identify
these pollutants:
1. If a pollutant was measured by two separate methods at the same site and that yield
similar results, such as measuring benzene with VOC and SNMOC methods, then the
two concentrations were averaged together. The purpose was to have one
concentration per pollutant per day per site. The two SVOC methods do not measure
the same suite of pollutants and do not necessarily yield similar results when they do
measure the same pollutants. Therefore, the results were not averaged together in
these instances. Metals were sampled with different filters, which can also produce
dissimilar results. Similar to SVOC, metals sampled with different filters were not
averaged together.
2. Each 24-hour speciated measurement was compared against the screening value.
Concentrations that were greater than the screening value are described as "failing the
screen."
3-18
-------
3. The number of failed screens was summed for each applicable pollutant. The number
of failures for each metal or SVOC was summed together to determine the total
number of failed screens for each applicable pollutant.
4. A total of 10,901 of 23,933 applicable concentrations (45.55%) failed screens. The
percent contribution of the number of failed screens was calculated for each
applicable pollutant.
5. The pollutants contributing to the top 95 percent of the total failed screens were
identified as pollutants of interest.
Table 3-7 identifies the pollutants that failed screens at least once, and summarizes the
total number of measured detections, percentage failed, and cumulative percentage of failed
screens. Following the steps above, the program-level pollutants of interest, as indicated by the
shading in Table 3-7, were identified as follows:
• Acetaldehyde
• Acrolein
• Arsenic
• Benzene
• 1,3-Butadiene
• Carbon Tetrachloride
• />-Dichlorobenzene
• Formaldehyde
• Hexachloro-1,3-butadiene
• Hexavalent chromium
• Manganese
• Naphthalene
• Tetrachloroethylene
The 2006 list of pollutants of interest is very similar to the 2005 list. Hexavalent
chromium and naphthalene are new for 2006, while nickel and total xylenes did not make the
list. A couple of items to note in regards to the 2006 pollutants of interest include the following:
Hexavalent chromium measurements were analyzed in a separate report for the 2005
program year (EPA, 2007c) and therefore were excluded from the risk screening
process in 2005.
3-19
-------
Table 3-7. Program-Level Risk Screening Summary
Pollutant
Acetaldehyde
Formaldehyde
Benzene
Carbon Tetrachloride
Acrolein
1,3 -Butadiene
£>-Dichlorobenzene
Tetrachloroethylene
Arsenic
Manganese
Hexavalent Chromium
Naphthalene
Hexachloro-1 ,3 -butadiene
Cadmium
Acrylonitrile
Nickel
Dichloromethane
Xylenes
Trichloroethylene
1,2-Dichloroethane
Benzo (a) pyrene
1, 1,2,2-Tetrachloroethane
Bromomethane
Methyl tert-Butyl Ether
Chloromethylbenzene
Dibenz (a,h) anthracene
Beryllium
Benzo (a) anthracene
Ethyl Aery late
Toluene
Benzo (b) fluoranthene
Cobalt
1,2-Dibromoethane
1, 1,2-Trichloroethane
# of Failed
Screens
1,814
1,599
1,329
1,323
1,048
1,011
644
535
485
349
96
90
86
74
70
66
64
55
36
30
19
16
16
9
8
5
3
3
3
3
2
2
1
1
#of
Measured
Detections
1,839
1,828
1,329
1,326
1,048
1,141
1,043
947
529
529
775
182
86
529
70
529
1,288
1,329
407
30
93
16
1,208
275
8
47
484
117
4
1,329
114
529
1
4
%of
Failed
Screens
98.64
87.47
100.00
99.77
100.00
88.61
61.74
56.49
91.68
65.97
12.39
49.45
100.00
13.99
100.00
12.48
4.97
4.14
8.85
100.00
20.43
100.00
1.32
3.27
100.00
10.64
0.62
2.56
75.00
0.23
1.75
0.38
100.00
25.00
%of
Total
Failures
16.64
14.67
12.19
12.14
9.61
9.27
5.91
4.91
4.45
3.20
0.88
0.83
0.79
0.68
0.64
0.61
0.59
0.50
0.33
0.28
0.17
0.15
0.15
0.08
0.07
0.05
0.03
0.03
0.03
0.03
0.02
0.02
0.01
0.01
Cumulative
%
Contribution
16.64
31.31
43.50
55.64
65.25
74.53
80.43
85.34
89.79
92.99
93.87
94.70
95.49
96.17
96.81
98.50
98.00
98.50
98.83
99.11
99.28
99.43
99.58
99.66
99.73
99.78
99.81
99.83
99.86
99.89
99.91
99.93
99.94
99.94
3-20
-------
Table 3-7. Program-Level Risk Screening Summary (Continued)
Pollutant
Benzo (k) fluoranthene
Chloromethane
Indeno(l,2,3-cd)pyrene
w-Hexane
Vinyl chloride
Chloroform
Total
# of Failed
Screens
1
1
1
1
1
1
10,901
#of
Measured
Detections
113
1,329
102
297
145
934
23,933
%of
Failed
Screens
0.88
0.08
0.98
0.34
0.69
0.11
45.55
% of Total
Failures
0.01
0.01
0.01
0.01
0.01
0.01
Cumulative
%
Contribution
99.95
99.96
99.97
99.98
99.99
100.00
• As mentioned in Section 2.5.1, there is currently some question about the reliability
of the acetonitrile data. Therefore, acetonitrile results were excluded from the risk
screening process and "pollutants of interest" designation.
• />-Dichlorobenzene is analyzed with the TO-15 method, while 1,4-dichlorobenzene is
analyzed with Method 8270. This is the same pollutant reported with two separate
names. Because these two analytical methods have vastly different characteristics
(i.e., MDL, collection media, etc.), heir concentrations were not averaged together.
However, the total number of failed screens has been added together in Table 3-7 and
is listed under/>-dichlorobenzene.
Refer to the summary tables in Appendices C through H and the raw monitoring data in
Appendices I through N for a closer examination of data trends for the other pollutants measured
by the program.
3.1.5 Non-Chronic Risk
In addition to the risk screening described above, non-chronic (short-term) risk was also
evaluated using the Agency for Toxic Substances and Disease Registry (ATSDR) acute and
intermediate minimal risk level (MRL) factors and California EPA (CALEPA) acute reference
exposure limit (REL) factors (ATSDR, 2006; CARB, 2006). Acute risk is defined as resulting
from exposures of 1 to 14 days while intermediate risk is defined as resulting from exposures of
15 to 364 days. For the non-chronic risk determination, the preprocessed daily measurements
were compared to the acute MRL and REL factors, and seasonal averages were compared to the
intermediate-term MRL.
3-21
-------
The daily average of a particular pollutant is simply the average concentration of all
measured detections. If there were at least seven measured detections within each season, then a
seasonal average was calculated. The seasonal average includes 1/2 MDL substitutions for all
non-detects. The substitution of 1/2 MDL for non-detects may have a significant impact on
pollutants that are rarely measured at or above the associated detection limit and/or have a
relatively high MDL. A seasonal average was not calculated for pollutants with less than seven
measured detections in a respective season. The spring season included concentrations from
March, April, and May; summer includes June, July, and August; autumn includes September,
October, and November; and winter includes January, February, and December. This analysis
was based on site-specific concentrations, but the number of exceedances has been summed to
the program-level.
Table 3-8 presents a summary of the program-level short-term risk analysis. Acrolein,
formaldehyde, and benzene were the only pollutants with least one concentration exceeding the
ATSDR and/or CALEPA risk factors. Out of 1,828 measured detections of formaldehyde, 26
exceeded the ATSDR MRL, but only 12 exceeded the CALEPA REL. The ATSDR MRL is
nearly half the CALEPA REL for formaldehyde (49 jug/m3 vs. 94 //g/m3, respectively). Out of
1,048 measured detections of acrolein, 1,048 exceeded the ATSDR MRL, and 1,019 exceeded
the CALEPA REL. Every measured detection of acrolein during the 2006 UATMP was greater
than 0.11 |ig/m3. However, the MRL and REL risk factors are very low for this pollutant, which
indicates that even very low concentrations of acrolein may present some health risk. With the
MDL for acrolein similar to, or slightly higher than these risk factors, most, if not all, of the
concentrations will likely exceed these risk factors. Only one concentration of benzene, out of
over 1,300 measured detections, exceeded the ATSDR MRL. Benzene does not have a
CALEPA acute risk factor. Exceedances of the acute risk factors are discussed in further detail
in Sections 4.0 through 31.0 on a site-specific basis.
Also presented in Table 3-8 is a summary of the program-level intermediate-term risk
analysis. Out of 125 seasonal averages of formaldehyde, only three seasonal averages of
formaldehyde, one occurring during the spring season, one occurring during summer, and one in
3-22
-------
Table 3-8. Program-Level Non-Chronic Risk Summary
Sampling
Method
TO-11A
TO- 15
TO- 15
Pollutant
Formaldehyde
Acrolein
Benzene1
Acute Risk
ATSDR
MRL
(Hg/m3)
49
0.11
28.75
#of
Exceedances/
# of Measured
Detections
26/1,828
1,048/1,048
1/1,329
CAL
EPA
REL
(Hg/m3)
94
0.19
NA
#of
Exceedances/
# of Measured
Detections
12/1,828
1,019/1,048
-
Intermediate Risk
ATSDR
MRL
(Hg/m3)
40
0.09
NA
#of
Winter
Exceedances/
# of Seasonal
Averages
0/29
20/20
~
#of
Spring
Exceedances/
# of Seasonal
Averages
1/36
13/13
~
#of
Summer
Exceedances/
# of Seasonal
Averages
1/29
21/21
~
#of
Autumn
Exceedances/
# of Seasonal
Averages
1/31
22/22
~
Indicates the use of the ATSDR re-calculated acute risk factor
to
-------
autumn, exceeded the ATSDR intermediate MRL (40 jug/m3). Out of 76 seasonal acrolein
averages, 76 exceeded the ATSDR intermediate MRL (0.09 //g/m3). Note that 2006 is the first
year that acrolein was sampled for a complete year. Benzene does not have an intermediate risk
factor, therefore, intermediate risk cannot be evaluated. Exceedances of the intermediate risk
factors are also discussed in further detail in Sections 4.0 through 31.0 on a site-specific basis.
Site-specific graphical displays of seasonal averages for the program-level pollutants of interest
are also presented and discussed in Section 3.2.2.2.
3.1.6 Pearson Correlations
This report uses Pearson correlation coefficients to measure the degree of correlation
between two variables. By definition, Pearson correlation coefficients always lie between -1 and
+1. Three qualification statements apply:
• A correlation coefficient of-1 indicates a perfectly "negative" relationship, indicating
that increases in the magnitude of one variable are associated with proportionate
decreases in the magnitude of the other variable, and vice versa.
• A correlation coefficient of+1 indicates a perfectly "positive" relationship, indicating
that the magnitudes of two variables both increase and both decrease proportionately.
• Data that are completely uncorrelated have Pearson correlation coefficients of 0.
Therefore, the sign (positive or negative) and magnitude of the Pearson correlation coefficient
indicate the direction and strength, respectively, of data correlations. Generally, correlations
greater than 0.50 or less than -0.50 are classified as strong. Correlations less than 0.50 and
greater than -0.50 are classified as weak.
When calculating correlations among the UATMP data, several measures were taken to
identify spurious correlations and to avoid introducing bias to the correlations:
• Data correlations were calculated only for the program-level pollutants of interest
identified in Section 3.1.4.
3-24
-------
• Correlations were calculated from the processed UATMP monitoring database in
which each pollutant has just one numerical concentration for each successful
sampling date, or the preprocessed daily measurements. Non-detects (and their
substituted value) were not included in this analysis.
Ambient air concentration tendencies often correlate with ambient meteorological
observations. The following three sections summarize how the pollutants of interest's
concentrations correlated with seven meteorological parameters: average maximum daily
temperature; average daily temperature; average daily dew point temperature; average daily wet
bulb temperature; average daily relative humidity; average daily sea level pressure; and average
wind speed.
3.1.6.1 Maximum and Average Temperature
Temperature is often a factor associated with high ambient air concentrations for some
pollutants, such as ozone. Higher temperature helps speed up the kinetic process as pollutants
react with each other. According to Table 3-9, the program-level pollutants of interest had
mostly weak correlations with maximum temperature and average temperature. Although the
correlations shown in Table 3-9 are generally low, they are nearly all positive, which indicates
that an increase in temperature is generally associated with a proportionate increase in
concentration.
The poor correlations exhibited at the program-level are not surprising due to the
complex and diverse local meteorology associated with the monitoring sites. For this report,
59 sites are spread across 28 states. As discussed in Sections 4.0 through 31.0, the temperature
parameters correlate better at select individual sites.
3.1.6.2 Moisture
Three moisture parameters were used in this study for correlation with the pollutants of
interest. The dew point temperature is the temperature to which moist air must be cooled to
reach saturation with respect to water. The wetbulb temperature is the temperature to which
moist air must be cooled by evaporating water into it at constant pressure until saturation is
3-25
-------
Table 3-9. Summary of Pearson Correlations between the Pollutants of Interest and Selected Meteorological Parameters
Pollutant
Acetaldehyde
Acrolein
Arsenic (PM10)
Arsenic (TSP)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
1,4-Dichlorobenzene
£>-Dichlorobenzene
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Hexavalent Chromium
Manganese (PM10)
Manganese (TSP)
Naphthalene
Tetrachloroethylene
#of
Measured
Detections
1839
1048
415
114
1329
1141
1326
56
987
1828
86
775
415
114
182
947
Maximum
Temperature
0.10
0.24
0.04
0.15
0.01
-0.12
0.40
-0.41
0.08
0.03
0.34
0.17
0.23
0.30
0.20
0.01
Average
Temperature
0.06
0.23
0.01
0.14
-0.01
-0.14
0.41
-0.52
0.11
0.02
0.37
0.16
0.20
0.31
0.18
0.00
Dew Point
Temperature
0.00
0.19
0.09
0.10
-0.04
-0.17
0.40
-0.58
0.12
0.02
0.35
0.03
-0.01
0.21
0.09
-0.01
Wet Bulb
Temperature
0.02
0.21
0.05
0.13
-0.03
-0.15
0.41
-0.57
0.12
0.02
0.38
0.10
0.11
0.26
0.14
0.00
Relative
Humidity
-0.15
-0.08
0.12
-0.08
-0.07
-0.09
0.05
-0.37
0.05
0.02
0.00
-0.18
-0.32
-0.27
-0.23
-0.04
Sea Level
Pressure
-0.16
-0.20
0.07
-0.05
0.05
0.07
-0.05
0.36
0.02
-0.51
0.00
0.09
0.08
0.04
0.03
0.01
Scalar
Wind
Speed
-0.11
0.00
-0.35
-0.07
-0.08
-0.04
-0.10
-0.09
0.00
-0.01
-0.08
-0.07
-0.22
-0.13
-0.17
0.07
to
-------
reached. The relative humidity is the ratio of the mixing ratio to its saturation value at the same
temperature and pressure (Rogers and Yau, 1989). All three of these parameters provide an
indication of how much moisture is presently in the air. Higher dew point and wet bulb
temperatures indicate increasing amounts of moisture in the air, while relative humidity is
expressed as a percentage with 100 percent indicating saturation. It should be noted that a high
dew point and wet bulb temperature do not necessarily equate to a relative humidity near
100 percent, nor does a relative humidity near 100 percent equate to a relatively high dew point
or wet bulb temperature.
As illustrated in Table 3-9, the three moisture parameters had mostly weak correlations
with the pollutants of interest. The sites participating in the 2006 program year were located in
different climatic zones ranging from a desert climate (west Texas) to a very moist climate
(Florida and Puerto Rico). As discussed in Sections 4.0 through 31.0, the moisture parameters
correlate better at select individual sites.
3.1.6.3 Wind and Pressure
Wind is an important component affecting air quality. Surface wind observations include
two primary components: wind speed and wind direction. Wind speed, by itself, is a scalar value
and is usually measured in nautical miles or knots (1 knot = 0.5 meters per second =1.15 miles
per hour). Wind direction describes where the wind is coming from, and is measured in degrees
where 0/360° is from the north, 90° is from the east, 180° is from the south, and 270° is from
the west. Wind speed and direction together represent a vector quantity, but in some cases wind
speed can be quantified separately (the scalar value). Pearson correlations were calculated for
the average scalar wind speed and are presented in Table 3-9. Wind direction is evaluated later
in this report.
As shown in Table 3-9, the scalar wind speed has weak correlations with the pollutants of
interest at the program level, which is consistent with the temperature and moisture parameter
observations. Geographical features such as mountains or valleys influence both wind speed and
wind direction. The sites used for sampling in the 2006 program year are located in different
geographic zones ranging from a mountainous region (Colorado) to a plains region (South
3-27
-------
Dakota). Additionally, sites located downwind may correlate better with the measured
concentrations than sites upwind. Nearly all of the correlations with wind speed are negative,
however, indicating that as wind speed decreases, concentrations of the pollutants of interest
tend to increase. As discussed in Sections 4.0 through 31.0, the scalar wind speed correlates
better at select individual sites.
Wind is created through changes in pressure. The magnitude of the pressure difference
(or pressure gradient) over an area is directly proportional to the magnitude of the wind speed.
The direction of the wind flow is governed by the direction of the pressure gradient. Sea level
pressure is the local station pressure corrected for elevation, in effect bringing all geographic
locations down to sea-level, thus making different topographical areas comparable. Overall, sea
level pressure correlated weakly with ambient concentrations. However, a strong correlation
was calculated for formaldehyde (-0.51).
3.2 Additional Program-Level Analyses of the 2006 UATMP Dataset
This section provides a summary of additional analyses performed on the 2006 UATMP
dataset at the program level and discusses the results. Additional program-level analyses include
an examination of the potential impact of motor vehicles and a review of how concentrations
vary among the sites themselves and from season-to-season. The results of some of these
analyses are further discussed in the state sections (4.0 through 32.0).
3.2.1 The Impact of Mobile Source Emissions on Spatial Variations
Mobile source emissions from motor vehicles contribute significantly to air pollution in
urban environments. Pollutants found in motor vehicle exhaust generally result from incomplete
combustion of vehicle fuels. Although modern vehicles and, more recently, vehicle fuels have
been engineered to minimize air emissions, all motor vehicles with internal combustion engines
emit a wide range of chemical pollutants. The magnitude of these emissions in urban areas
primarily depends on the volume of traffic, while the chemical profile of these emissions
depends more on vehicle design and fuel formulation. This report uses four parameters to
evaluate the impact of motor vehicle emissions on ambient air quality:
• Estimated motor vehicle ownership data;
3-28
-------
• BTEX concentration profiles;
• Estimated daily traffic volumes; and
• Mobile source tracer analysis.
3.2.1.1 Motor Vehicle Ownership Data
As an indicator of motor vehicle emissions near the UATMP monitoring sites, Table 3-10
presents estimates of the number of vehicles owned by residents in the county in which the
monitoring site is located. Where possible, actual county-level vehicle registration data were
obtained from the state or local agency. If data were not available, vehicle registration data are
available at the state-level (EIA, 2006). The county proportion of the state population was then
applied to the state registration count. For each UATMP county, a vehicle registration to
population ratio was developed. Each ratio was then applied to the 10-mile population
surrounding the monitors (from Table 2-3). These estimated values are discussed in the
individual state sections.
For purposes of comparison, the county-level motor vehicle ownership data and the
arithmetic mean of hydrocarbons are presented in Table 3-10. Figure 3-1 compares 10-mile
vehicle ownership to the hydrocarbon mean graphically. The trendline in the figure indicates a
very slight positive linear correlation between motor vehicle ownership and ambient air
concentrations of hydrocarbons. A Pearson correlation calculation from this data yields a weak
positive correlation (0.15). However, other factors might impact the reliability of motor vehicle
ownership data as an indicator of ambient air monitoring data results:
• Estimates of higher car ownership surrounding a monitoring site do not necessarily
imply increased motor vehicle use in the immediate vicinity of a monitoring site.
Conversely, sparsely populated regions often contain heavily traveled roadways.
• Emission sources in the area other than motor vehicles may significantly affect levels
of hydrocarbons in the ambient air.
3-29
-------
Table 3-10. Summary of Mobile Source Information by Monitoring Site
Site
AZFL
BAPR
BOMA
BTUT
CANC
CANJ
CHNJ
CHSC
CNEP
CUSD
DEMI
ELNJ
ETAL
FLFL
GAFL
GPCO
GPMS
HAKY
IDIN
INDEM
ININ
ITCMI
LAOR
LDTN
MAWI
MIMN
MSTN
MUTX
MVWI
NBAL
County Motor
Vehicle
Registration
1,461,505
13,912
424,907
223,379
28,333
371,045
353,934
42,726
29,815
14,191
1,423,637
381,155
614,075
1,637,132
1,189,885
154,175
171,674
22,704
897,388
453,146
897,388
33,580
33,263
50,519
425,763
1,097,109
50,519
731,956
95,112
614,075
2006 Estimated
County
Population
924,413
23,028
687,610
276,259
27,638
517,001
493,160
43,191
39,774
7,944
1,971,853
531,088
656,700
1,787,636
1,157,738
134,189
171,875
29,753
865,504
494,202
865,504
38,674
24,345
44,566
463,826
1,122,093
44,566
921,006
88,983
656,700
Traffic Data
Near Site
(Daily Average)
51,000
10
27,287
33,310
100
62,000
12,623
550
5
1,940
12,791
170,000
30,000
8,000
81,400
19,572
17,000
500
30,916
42,950
97,780
100,000
55
12,945
23,750
10,000
7,287
4,374
5,990
2,000
County-Level
On-road
Emissions
(tpy)
4,829.76
8.77
1,140.61
1,116.69
164.10
1,294.50
1,718.49
217.35
271.83
43.15
9,892.20
1,327.73
4,009.60
7,627.16
5,580.45
557.45
862.14
145.19
4,096.68
1,518.45
4,096.68
180.93
304.94
365.94
1,761.58
4,147.23
365.94
2,956.09
353.76
4,009.60
County-Level
Non-road
Emissions
(tpy)
2,072.04
108.79
1,962.38
428.66
37.39
704.57
1,396.98
48.21
107.68
37.87
1,902.04
664.49
839.02
2,681.07
2,140.55
223.19
1,392.60
17.63
1,195.63
956.59
1,195.63
605.64
114.20
181.80
1,040.38
1,418.38
181.80
1,337.08
273.93
839.02
Hydrocarbon
Arithmetic
Mean
(ppbv)
NA
5.01
NA
3.79
NA
3.36
1.28
NA
1.47
2.58
3.09
6.25
10.56
NA
NA
5.31
2.44
NA
NA
NA
NA
NA
NA
2.23
1.89
2.61
2.08
2.22
NA
6.89
Acetylene
Arithmetic
Mean
(ppbv)
NA
0.90
NA
1.16
NA
1.05
0.52
NA
0.46
0.76
0.97
1.45
6.37
NA
NA
1.69
0.56
NA
NA
NA
NA
NA
NA
0.62
0.76
1.07
0.48
0.82
NA
1.92
-------
Table 3-10. Summary of Mobile Source Information by Monitoring Site (continued)
Site
NBIL
NBNJ
ORFL
PITX
PRRI
PVAL
PXSS
RRTX
RTPNC
S4MO
SDGA
SEWA
SFSD
SIAL
SJPR
SKFL
SMFL
SPIL
SYFL
TOOK
TRTX
TSOK
TUMS
TUOK
UNVT
WADC
WETX
WPIN
YDSP
County Motor
Vehicle
Registration
2,133,068
564,799
1,043,571
731,956
142,334
614,075
3,682,234
285,183
188,168
1,438,244
458,290
1,726,115
202,696
614,075
145,642
1,461,505
1,189,885
2,133,068
1,189,885
498,898
731,956
498,898
69,888
498,898
122,119
236,789
731,956
897,388
533,438
2006 Estimated
County
Population
5,288,655
786,971
1,043,500
921,006
635,596
656,700
3,768,123
353,830
246,896
1,347,691
723,602
1,826,732
163,281
656,700
221,546
924,413
1,157,738
5,288,655
1,157,738
577,795
921,006
577,795
79,714
577,795
150,069
581,530
921,006
865,504
736,310
Traffic Data
Near Site
(Daily Average)
29,600
63,000
59,000
33,936
5,500
NA
250
20,900
12,000
22,840
98,510
20,000
4,320
2,700
250
50,500
18,700
214,900
5,142
500
27,114
62,500
4,900
82,600
1,200
75,800
5,733
11,514
2,200
County-Level
On-road
Emissions
(tpy)
8,766.59
2,360.85
5,584.04
2,956.09
1,996.79
4,009.60
10,069.61
840.49
1,263.01
1,376.92
3,173.30
11,754.01
547.35
4,009.60
493.18
4,829.76
5,580.45
8,766.59
5,580.45
3,482.32
2,956.09
3,482.32
438.24
3,482.32
896.16
1,277.49
2,956.09
4,096.68
2,208.64
County-Level
Non-road
Emissions
(tpy)
5,441.27
1,329.95
2,305.52
1,337.08
704.39
839.02
5,455.91
324.92
337.11
481.95
1,110.37
4,088.72
198.34
839.02
1,091.92
2,072.04
2,140.55
5,441.27
2,140.55
890.73
1,337.08
890.73
178.81
890.73
358.75
390.59
1,337.08
1,195.63
529.75
Hydrocarbon
Arithmetic
Mean
(nnhv)
1.82
2.12
NA
1.64
NA
0.86
NA
3.62
NA
2.60
NA
NA
1.61
6.27
6.65
NA
NA
2.61
NA
5.27
2.36
6.16
1.82
4.91
NA
NA
9.16
NA
8.15
Acetylene
Arithmetic
Mean
(pphv)
0.72
0.73
NA
0.60
NA
0.34
NA
0.68
NA
0.80
NA
NA
0.51
1.45
1.24
NA
NA
0.89
NA
0.66
0.55
0.61
0.56
0.61
NA
NA
1.56
NA
2.71
-------
Figure 3-1. Comparison of Average Hydrocarbon Concentration vs. 10-Mile Vehicle Registration
to
1,800,000 -,
1,600,000
1,400,000
1,200,000
tn
8"
C£
• 1,000,000
0)
E 800,000
o
400,000
200,000
468
Average Hydrocarbon Concentration (ppbv)
10
12
-------
3.2.1.2 Estimated Traffic Volume Data
When a monitoring site is being characterized, a parameter often recorded is the number
of vehicles that pass the monitoring site on a daily basis. Traffic data were obtained from the
site information provided on EPA's AQS database or by contacting state and local agencies.
Table 3-10 contains the estimated daily traffic values, as well as county-level on-road and non-
road HAP emissions.
The highest daily traffic volume occurred at the SPIL and ELNJ sites, with over 214,900
and 170,000 vehicles passing by these monitoring sites, respectively. SPIL is located near
Interstate 294 near the Chicago-O'Hare International Airport, and ELNJ is located near Exit 13
on Interstate 95. The average hydrocarbon (total) value of the preprocessed daily measurements
at ELNJ was 6.25 ppbv, which is ranked 7th among sites that measured hydrocarbons. ETAL,
WETX, YDSP, NBAL, SJPR, and SIAL each had average hydrocarbon concentrations greater
than ELNJ, yet their traffic counts are ranked 9th, 22nd, 26th, 27th, 28th, and 31st highest,
respectively. At SPIL, the average hydrocarbon (total) value was only 2.61 ppbv, which ranked
17th.
Specific characterizations for these sites appear in the separate state sections. As shown
in Figure 3-2, there does not appear to be a direct correlation between traffic counts and average
hydrocarbon concentrations. The calculated Pearson correlation was only 0.01, indicating hardly
any relationship between the two at all. This observation might suggest that the site traffic
counts may need to be updated, as many were recorded ten or more years ago.
Estimated on-road county emissions were highest in Wayne County, MI, which is where
DEMI is located. The hydrocarbon average for DEMI ranked 16th highest. Estimated non-road
county emissions were highest in Cook County, IL. Non-road emission sources include, but are
not limited to, activities from airplanes, construction vehicles, and lawn and garden equipment.
Refer to Table 3-10 and Figure 3-2 for a more detailed look at mobile source emissions and
average hydrocarbon concentrations.
3-33
-------
Figure 3-2. Comparison of Average Hydrocarbon Concentration vs. Daily Traffic Volume
250,000 T
200,000
0)
E
o
I
TO
Q
0)
150,000
100,000
50,000
•
_t_
» * »
468
Average Hydrocarbon Concentration (ppbv)
10
12
-------
3.2.1.3 Mobile Source Tracer Analysis
Research has shown that acetylene can be used as a signature compound for automotive
emissions (Warneck, 1988; NRC, 1991) because this VOC is not typically emitted from biogenic
or stationary sources. As summarized in Table 3-10, many UATMP sites are located in high
traffic areas (e.g., ELNJ and SPIL). The average preprocessed acetylene concentration for each
site is also summarized in Table 3-10. As presented in Figure 3-3, there does not appear to be a
direct correlation between daily traffic and acetylene concentrations. The calculated Pearson
correlation was -0.01, indicating a very weak relationship. Similar to the comparison between
hydrocarbons and traffic volume, this observation might suggest that the site traffic counts may
need to be updated, as many were recorded ten or more years ago.
Nearly all emissions of ethylene are due to automotive sources, with the exception of
activities related to natural gas production and transmission. Ethylene is not detected as a VOC
by the TO-15 sampling method, but is detected using the SNMOC method. For the five sites that
chose the SNMOC option, ethylene to acetylene concentration ratios were computed and
compared to a ratio developed in numerous tunnel studies, and are presented in Table 3-11. An
ethylene to acetylene ratio of 1.7 to 1 is indicative of mobile sources (TCEQ, 2002). Of the sites
that sampled SNMOC, NBIL's ethylene to acetylene ratio was the closest to the expected 1.7 to 1
ratio (1.74 to 1). These results are discussed further in the individual state sections.
Table 3-11. Average Ethylene to Acetylene
Ratios for Sites that Measured SNMOC
Site
BTUT
CUSD
GPMS
NBIL
SFSD
Average Ethylene to
Acetylene Ratio
1.30
1.43
1.47
1.74
1.22
% Difference from
1.70 Ratio
-23.34
-16.05
-13.76
2.59
-28.43
3-35
-------
Figure 3-3. Comparison of Average Acetylene Concentration vs. Daily Traffic Volume
250,000 T
200,000
0)
E
o
I
TO
Q
0)
150,000
100,000
50,000
• • *
3 4
Average Aceylene Concentration (ppbv)
-------
3.2.1.4 BTEX Concentration Profiles
The magnitude of emissions from motor vehicles generally depends on the volume of
traffic in urban areas, but the composition of these emissions depends more on vehicle design.
Because the distribution of vehicle designs (i.e., the relative number of motor vehicles of
different styles) is probably quite similar from one urban area to the next, the composition of air
pollution resulting from motor vehicle emissions is not expected to exhibit significant spatial
variations. In support of this hypothesis, previous air monitoring studies have observed
relatively constant composition of ambient air samples collected along heavily traveled urban
roadways (Conner et al., 1995). Roadside studies have found particularly consistent proportions
of four hydrocarbons (benzene, toluene, ethylbenzene, and the xylene isomers - the "BTEX"
compounds) both in motor vehicle exhaust and in ambient air near roadways.
To examine the impact of motor vehicle emissions on air quality at the 2006 UATMP
monitoring sites, Table 3-12 and Figure 3-4 compare concentration ratios for the BTEX
compounds measured during the 2006 UATMP to the ratios reported in a roadside study (Conner
et al., 1995). This comparison provides a qualitative depiction of how greatly motor vehicle
emissions affect air quality at the UATMP monitoring sites: the more similar the concentration
ratios at a particular monitoring site are to those of the roadside study, the more likely that motor
vehicle emissions impact ambient levels of hydrocarbons at that location.
As presented in Figure 3-4, the concentration ratios for BTEX compounds measured at
most UATMP monitoring sites bear some resemblance to the ratios reported in the roadside
study. The BTEX ratios at the BAPR and SJPR monitoring sites appear to be the most similar to
the roadside study profile. For all monitoring sites, the toluene-ethylbenzene ratio is the largest
of the three ratios, with the exceptions of CNEP, CUSD, PVAL, and SIAL. The benzene-
ethylbenzene ratio is the smallest of the three ratios at eight sites, while the xylenes-ethylbenzene
ratio is the smallest at 26 sites. These observations suggest, though certainly do not prove, that
emissions from motor vehicles have an impact on the levels of hydrocarbons in urban ambient
air, although are not necessarily the only contributing factor.
3-37
-------
Table 3-12. Comparison of Concentration Ratios for BTEX Compounds
vs. Roadside Study
Site
Roadside Study
BAPR
BTUT
CANJ
CHNJ
CNEP
CUSD
DEMI
ELNJ
ETAL1
GPCO
GPMS
LDTN
MAWI
MIMN
MSTN
MUTX1
NBAL1
NBIL
NBNJ
PITX1
PVAL1
RRTX1
S4MO
SFSD
SIAL1
SJPR
SPIL
TOOK
TRTX1
TSOK
TUMS
TUOK
WETX1
YDSP1
Benzene-
Ethylbenzene Ratio
2.85
3.11+0.26
4.86 + 0.34
4.67 + 0.38
5.60 + 0.50
7.61 + 1.65
6.42 + 0.66
4.92 + 0.52
3.69 + 0.33
3.64 + 0.43
4.04 + 0.34
4.16 + 0.79
7.02 + 0.68
5.83+0.89
4.71+0.33
5.88 + 0.60
1.95+0.34
3.12 + 0.80
5.74 + 0.58
3.94 + 0.45
2.00 + 0.45
6.77 + 2.99
1.91+0.39
3.55+0.43
5.74 + 0.51
11.38 + 6.08
2.48 + 0.23
5.30 + 0.64
5.33+0.62
2.00 + 0.33
1.36 + 0.33
6.10 + 1.89
4.10 + 1.02
1.93+0.37
3.02 + 0.27
Toluene-
Ethylbenzene Ratio
5.85
9.42 + 2.09
8.49 + 0.44
7.41+0.66
5.71+0.42
6.50+1.59
6.00 + 0.51
6.67 + 0.69
6.73+0.34
5.25+0.30
7.20 + 0.40
6.89 + 0.55
9.89 + 0.85
5.95+0.65
5.90 + 0.42
12.48+1.46
3.08 + 0.39
4.38 + 0.88
6.87 + 0.74
5.70 + 0.34
3.06 + 0.61
9.56 + 1.17
11.87 + 1.77
5.73+0.58
10.70+2.32
6.24 + 1.08
8.05 + 0.99
7.09 + 0.51
12.22 + 1.24
4.19 + 0.80
6.34 + 2.10
9.47 + 0.95
11.68+1.08
3.46 + 0.59
5.93+0.42
Xylenes-
Ethylbenzene Ratio
4.55
4.22+0.18
4.52+0.19
3.60+0.22
3.04+0.20
3.31+0.26
3.49+0.25
3.77+0.20
3.84+0.24
3.78 + 0.18
4.61+0.15
3.36 + 0.17
3.44 + 0.13
3.42 + 0.37
3.75 + 0.12
3.64 + 0.17
1.49+0.17
3.84+0.55
3.40+0.19
3.79+0.20
1.48+0.17
3.43+0.21
1.43+0.23
2.80+0.20
3.31+0.18
4.01+0.31
4.18+0.16
3.54+0.16
4.60+0.19
1.71+0.20
2.65+0.21
3.51+0.16
3.73+0.21
2.22+0.30
3.59 + 0.08
The ratios for these sites include data from both 2005 and 2006.
3-38
-------
Figure 3-4. Comparison of Concentration Ratios for BTEX Compounds vs. Roadside Study
VO
16.00
14.00
0.00
Roadside BAPR BTUT CANJ CHNJ CNEP CUSD DEMI ELNJ ETAL GPCO GPMS
Study Site
D Benzene-Ethylbenzene
I Toluene-Ethylbenze
DXylenes-Ethylbenzene
-------
Figure 3-4. Comparison of Concentration Ratios for BTEX Compounds vs. Roadside Study (Continued)
16.00
14.00
0.00
-
1— 1
Roadside LDTN MAWI MIMN MSTN MUTX NBAL NBIL NBNJ PITX PVAL RRTX
Study Site
D Benzene-Ethylbenzene
I Toluene-Ethylbenze
DXylenes-Ethylbenzene
-------
Figure 3-4. Comparison of Concentration Ratios for BTEX Compounds vs. Roadside Study (Continued)
14.00
12.00
10.00
8.00
o
is
a:
c
o
is
g 6.00
o
o
4.00
2.00 --
0.00
Site
D Benzene-Ethylbenzene
IToluene-Ethylbenze
DXylenes-Ethylbenzene
-------
3.2.2 Variability Analysis
Two types of variability are analyzed for this report. The first type examines the
coefficient of variation for each of the pollutants of interest across the UATMP sites. Seasonal
variability is the second type of variability analyzed in this report. The UATMP concentration
data were divided into the four seasons, as described in Section 3.1.5.
3.2.2.1 Coefficient of Variation
The coefficient of variation provides a relative measure of variability by expressing
standard deviations to the magnitude of the arithmetic mean. Figures 3-5 to 3-17 are graphical
displays of site-specific standard deviation versus average concentration. This analysis is best
suited for comparing variability across data distributions for different sites and pollutants.
Pollutants of interest whose data points are clustered together indicate uniformity in how the
concentrations are dispersed among the sites. This suggests that concentrations are affected by
typical and consistent sources (e.g., mobile sources). Data points that are not clustered suggest
the likelihood of a stationary source not typically found in most urban areas (e.g., coke
manufacturing facility).
Figure 3-10 for formaldehyde and Figure 3-14 for/>-dichlorobenzene show that these
compounds exhibit this "clustering" while Figure 3-5 for 1,3-butadiene and Figure 3-6 for
acetaldehyde do not. The data point in the far right of Figure 3-10 is not clustered with most of
the other points. This value belongs to INDEM, which tends to have a much higher
formaldehyde average than other UATMP sites. INDEM resides in a heavily industrialized area,
and this may be the result of emissions from nearby petroleum refinery and steel manufacturing
facilities.
3.2.2.2 Seasonal Variability Analysis
Figures 3-18 to 3-29 provide a graphical display of the average concentrations by season
for the program-level pollutants of interest. Seasonal averages are calculated based on criteria
specified in Section 3.1.5. If the pollutant of interest has a corresponding ATSDR Intermediate
MRL, then this value is indicated on the graph and is plotted where applicable.
3-42
-------
Figure 3-5. Coefficient of Variation Analysis of 1,3-Butadiene Across 34 Sites
0.1
0.2
0.3
0.4
0.5
0.6
0.7
Average Concentration (|jg/m )
-------
Figure 3-6. Coefficient of Variation Analysis of Acetaldehyde Across 45 Sites
o
5
o
I
Average Concentration (|jg/m )
-------
Figure 3-7. Coefficient of Variation Analysis of Acrolein Across 33 Sites
0.5
1.5
2.5
3.5
4.5
Average Concentration (|jg/m3)
-------
Figure 3-8. Coefficient of Variation Analysis of Benzene Across 34 Sites
Average Concentration (|jg/m )
-------
Figure 3-9. Coefficient of Variation Analysis of Carbon Tetrachloride Across 34 Sites
0.8
0.6
5
o
0.4
0.2
• ^ *
•
0.2
0.4
0.6
0.8
Average Concentration (|jg/m )
-------
Figure 3-10. Coefficient of Variation Analysis of Formaldehyde Across 45 Sites
oo
c
o
5
Q
TO
Average Concentration (|jg/m )
-------
Figure 3-11. Coefficient of Variation Analysis of Hexachloro-l,3-Butadiene Across 29 Sites
c
o
5
Q
TO
W
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.15
Average Concentration (|jg/m )
-------
Figure 3-12. Coefficient of Variation Analysis of Hexavalent Chromium Across 23 Sites
0.18
0.16
0.14
0.12
o
.2 0
0)
0
•o 0
0.
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
Average Concentration (ng/m )
-------
0.7
0.6
0.5
Figure 3-13. Coefficient of Variation Analysis of Naphthalene Across 6 Sites
o
0)
0
0.3
CO
0.2
0.1
0.1
0.2
0.3
0.4
0.5
0.6
0.7
Average Concentration (|jg/m )
TO-13
8270
•Linear (TO-13)
-------
Figure 3-14. Coefficient of Variation Analysis of/J-Dichlorobenzene/l,4-Dichlorobenzene Across 35 Sites
to
TO-15
8270C
Linear (TO-15)
1 1.5
2.5
3.5
4.5
-1
Average Concentration ([iglm )
-------
Figure 3-15. Coefficient of Variation Analysis of Tetrachloroethylene Across 34 Sites
3 -r
2.5
Q
i
0.5
1.5
2.5
-0.5
Average Concentration (|jg/m )
-------
Figure 3-16. Coefficient of Variation Analysis of Arsenic Across 21 Sites
PM10
TSP
Linear (PM10)
Linear (TSP)
Average Concentration (ng/m )
-------
Figure 3-17. Coefficient of Variation Analysis of Manganese Across 21 Sites
200
180
160
140
120
I 100
0)
Q
•g 80
60
40
20
PM10
TSP
Linear (PM10)
Linear (TSP)
X
X
X
X
X
X
X
X
X
X
X
60
80
100
120
140
160
180
Average Concentration (ng/m )
-------
0.50
0.45
0.40
_ 0.35
CO
a o.so
c
o
Figure 3-18a. Comparison of Average Seasonal 1,3-Butadiene Concentration by Season
1,3-Butadiene has no ATSDR Intermediate MRL
0.25
0)
o
0.20
O)
0.15 -
0.10 --
0.05 --
0.00
BAPR BTUT CANJ CHNJ CNEP CUSD DEMI ELNJ GPCO GPMS LDTN MAWI MIMN
Site
DWinter
I Spring
DSummer
D Autumn
-------
Figure 3-18b. Comparison of Average Seasonal 1,3-Butadiene Concentration by Season (Continued)
1,3-Butadiene has no ATSDR Intermediate MRL
0.00
MSTN NBAL NBIL NBNJ S4MO SFSD SIAL SJPR SPIL TOOK TSOK TUMS TUOK YDSP
Site
D Winter
I Spring
DSummer
D Autumn
-------
Figure 3-19a. Comparison of Average Seasonal Acetaldehyde Concentration by Season
oo
8.00
7.00
6.00
] 5.00
.0
1 4.00
I
O 3.00
2.00 -
1.00 -
0.00
ATSDR Intermediate MRL for acetaldehyde = 90 |jg/m
"Th i
Site
DWinter
• Spring
DSummer
DAutumn
-------
Figure 3-19b. Comparison of Average Seasonal Acetaldehyde Concentration by Season (Continued)
8.00
7.00
6.00
n
E
1? 5.00
o
2 4.00
I
o
<-> 3.00
O)
2.00
1.00
0.00
ATSDR Intermediate MRL for acetaldehyde = 90 |jg/m
Site
DWinter
• Spring
DSummer
DAutumn
-------
Figure 3-20a. Comparison of Average Seasonal Acrolein Concentration by Season
3.00
2.50
ATSDR Intermediate MRL for acrolein = 0.09 |jg/m
0.00
BAPR BTUT CANJ CHNJ CNEP CUSD DEMI ELNJ GPCO GPMS LDTN MSTN NBAL NBIL
Site
DWinter
• Spring
DSummer
DAutumn
-------
3.00
2.50
2.00
Figure 3-20b. Comparison of Average Seasonal Acrolein Concentration by Season (Continued)
ATSDR Intermediate MRL for acrolein = 0.09 |jg/m
.0
1 1.50
I
o
o
O)
1.00
0.50
0.00
I
NBNJ PITX RRTX S4MO SFSD SJPR SPIL TOOK TRTX TSOK TUMS TUOK YDSP
Site
DWinter
• Spring
DSummer
DAutumn
-------
Figure 3-21a. Comparison of Average Seasonal Arsenic PMio Concentration by Season
to
6.00
5.00
4.00
)
.0
I 3.00
a>
o
o
o
O)
2.00
1.00
0.00
ATSDR Intermediate MRL for arsenic = 300 ng/m .
BOMA BTUT
IDIN ININ NBAL NBIL
Site
PITX PXSS S4MO WETX
D Winter
I Spring
nSummer
D Autumn
-------
Figure 3-21b. Comparison of Average Seasonal Arsenic TSP Concentration by Season
6.00
5.00
4.00
)
3.00
I
o
o
O)
« 2.00
1.00
0.00
n
ATSDR Intermediate MRL for arsenic = 300 ng/m .
fl
ETAL MIMN
NBAL PVAL SIAL TOOK TSOK TUOK
Site
D Winter
I Spring
DSummer
D Autumn
-------
Figure 3-22a. Comparison of Average Seasonal Benzene Concentration by Season
5.00
ATSDR Intermediate MRL for benzene = 20 |jg/m
4.00
=: 3.00
o
I
o
O)
2.00
(I
1.00
0.00
BAPR BTUT CANJ CHNJ CNEP CUSD DEMI ELNJ ETAL GPCO GPMS LDTN MAWI MIMN MSTN MUTX
Site
DWinter
• Spring
DSummer
DAutumn
-------
5.00
Figure 3-22b. Comparison of Average Seasonal Benzene Concentration by Season (Continued)
4.00
ATSDR Intermediate MRL for benzene = 20
=: 3.00
o
I
o
O)
2.00
1.00
0.00
NBAL NBIL NBNJ PITX PVAL RRTX S4MO SFSD SIAL SJPR SPIL TOOK TRTX TSOK TUMS TUOK YDSP
Site
DWinter
• Spring
DSummer
DAutumn
-------
Oi
Figure 3-23a. Comparison of Average Seasonal Carbon Tetrachloride Concentration by Season
1.50
1.25
1.00
.0
1 0.75
I
o
o
O)
0.50 --
0.25 --
0.00
ATSDR Intermediate MRL for carbon tetrachloride = 200 |jg/m
IT
BAPR BTUT CANJ CHNJ CNEP CUSD DEMI ELNJ ETAL GPCO GPMS LDTN MAWI MIMN MSTN MUTX NBAL
Site
DWinter
• Spring
DSummer
DAutumn
-------
Figure 3-23b. Comparison of Average Seasonal Carbon Tetrachloride Concentration by Season (Continued)
1.50
ATSDR Intermediate MRL for carbon tetrachloride = 200 |jg/m
0.00
NBIL NBNJ PITX PVAL RRTX S4MO SFSD SIAL SJPR SPIL TOOK TRTX TSOK TUMS TUOK YDSP
Site
DWinter
• Spring
DSummer
DAutumn
-------
oo
Figure 3-24a. Comparison of Average Seasonal Formaldehyde Concentration by Season
45.0
36.0
•== 27.0
.o
"TO
+-
I
o 18.0
O
9.0
0.0
ATSDR Intermediate MRL for formaldehyde = 40 ug/m .
rffTl r*^
/
Site
INDEM formaldehyde values - spring
,3V
(103.33 ug/m ); summer (101.00
ug/m3); and autumn (48.16 ug/m3).
DWinter
• Spring
DSummer
DAutumn
-------
Figure 3-24b. Comparison of Average Seasonal Formaldehyde Concentration by Season (Continued)
ATSDR Intermediate MRL for formaldehyde = 40 |jg/m3.
36.0
E
B)
^ 27.0
c
o
is
•+•»
I
o 18.0
O)
9.0
0.0
n rr
lEllnmMM
rfhi
1
In
Site
DWinter
Spring
DSummer
DAutumn
-------
Figure 3-25. Comparison of Average Seasonal Hexavalent Chromium Concentration by Season
0.25
0.20
E
"3)
£ 0.15
o
OJ C
-------
Figure 3-26a. Comparison of Average Seasonal Manganese PMio Concentration by Season
150.00
125.00
100.00
ATSDR Intermediate MRL for manganese = 500 ng/m
E
"3)
.0
I 75.00
a>
o
o
o
* 50.00
25.00
0.00
m-n
n nil H-Hi
n
n
BOMA BTUT IDIN ININ
NBAL NBIL PITX PXSS S4MO WETX
Site
D Winter
I Spring
nSummer
D Autumn
-------
Figure 3-26b. Comparison of Average Seasonal Manganese TSP Concentration by Season
to
I
"3)
150.00
125.00
100.00
j= 75.00
§
u
o
o
50.00
25.00
0.00
n
ETAL MMN
n
ATSDR Intermediate MRL for manganese = 500 ng/m
NBAL PVAL SIAL TOOK TSOK TUOK
Site
D Winter
I Spring
nSummer
D Autumn
-------
Figure 3-27. Comparison of Average Seasonal Naphthalene Concentration by Season
"3)
c
o
0.6
0.5
0.4
oj 2 03
I +J U.O
3 §
o
O)
0.2
0.1
0.0
ETAL
GPMS*
* SW8270
Naphthalene has no ATSDR Intermediate MRL
ITCMI
NBAL
PVAL
SIAL
Site
D Winter
I Spring
D Summer
D Autumn
-------
Figure 3-28a. Comparison of Average Seasonal /7-Dichlorobenzene by Compendium Method TO-15 Concentration by Season
1 ./ J
1.50
1.25
ro
O)
"=" 1.00
o
2
= 0.75
0
O
0)
0.50
0.25
0.00
-
"
-
I-,
p-Dichlorobenzene has no ATSDR Intermediate MRL
n-T i-iTU n i-LrTI r H
mil mrr [Tllnrilf [HTl fl ill l\]
BAPR BTUT CANJ CHNJ DEMI ELNJ GPCO GPMS LDTN MIMN MSTN NBAL NBIL
Site
D Winter • Spring D Summer D Autumn
-------
Figure 3-28b. Comparison of Average Seasonal /7-Dichlorobenzene by Compendium Method TO-15 Concentration by Season
(Continued)
1.75
1.50
1.25
c 1.00
o
I
o
o
O)
0.75
0.50
0.25
0.00
SJPR p-dichlorobenzene value
-winter (4.18 ug/m3).
m n n r
-
—
-i
NBNJ PITX RRTX S4MO
DWinter
n
p-Dichlorobenzene has no ATSDR Intermediate MRL
i-
JTlHl 1 1 HI \\\
SFSD SIAL SJPR SPIL TOOK TRTX TSOK TUMS TUOK YDSP
Site
• Spring DSummer DAutumn
-------
Figure 3-28c. Comparison of Average Seasonal 1,4-Dichlorobenzene (p-Dichlorobenzene) by Compendium Method TO-13A
Concentration by Season
o
is
1.75
1.50
1.25
1.00
o
o
O)
0.75
0.50
0.25
0.00
1,4-Dichlorobenzene has no ATSDR Intermediate MRL
GPMS
Site
D Winter
I Spring
DSummer
DAutumn
-------
Figure 3-29a. Comparison of Average Seasonal Tetrachloroethylene Concentration by Season
n *!
00
n n
n n
n
tfi r
__
Hmnn
r
r
ATSDR Intermediate MRL for tetrachloroethylene = 1200 ug/m3.
i—i r- 1
nr mm
BAPR BTUT CANJ CHNJ CUSD DEMI ELNJ GPCO GPMS LDTN MSTN
Site
D Winter
I Spring
nSummer
D Autumn
-------
oo
Figure 3-29b. Comparison of Average Seasonal Tetrachloroethylene Concentration by Season (Continued)
2.0
1.8 -
1.5 -
o> 1.3
£ 1.0
§
O
0.8
0.5 -
0.3 -
0.0
ATSDR Intermediate MRLfortetrachloroethylene = 1200 ug/m
NBIL NBNJ S4MO SFSD SJPR SPIL TOOK TSOK TUMS TUOK YDSP
Site
DWinter
I Spring
DSummer
D Autumn
-------
Many of the pollutants of interest, such as acrolein and tetrachloroethylene, were
measured frequently in some seasons but not in others. As a result of the seasonal average
criteria, there are gaps in the figures for these pollutants for certain seasons. For example,
Figure 3-29 shows that tetrachloroethylene had few spring averages, even though many of the
sites sampled year-round.
Other pollutants of interest, such as formaldehyde, benzene, and acetaldehyde, were
detected year-round. Comparing the seasonal averages for the sites with four valid seasonal
averages often reveals a trend for these pollutants. For example, formaldehyde averages tended
to be higher in the summer, as shown in Figure 3-24, while benzene averages tended to be higher
in the autumn and winter, as shown in Figure 3-22. The seasonal behavior of these two
pollutants suggests the influence of reformulated gasoline (RFG), as the benzene content is
typically lowered during the warmer periods (i.e., summer and spring). Refineries often begin
production of RFG during the spring and end in the autumn. Additionally, methyl-fert-butyl
ether (MTBE) was used as an RFG additive in fuels to replace the lowered benzene content.
Research has shown that the combustion of fuels containing MTBE lead to the secondary
production of formaldehyde. Thus, while benzene may experience a reduction in concentrations
during the summer months, formaldehyde concentrations may increase if MTBE is used in the
gasoline blend. Other pollutants, such as carbon tetrachloride, may not exhibit such a trend.
Of the sites that sampled metals, most are located in Alabama, Texas, Oklahoma, and
Indiana. Unfortunately, the Texas and Alabama sites sampled through early summer, so only
one or two seasonal averages are available. The Oklahoma and Indiana sites began sampling
during the fall, so only autumn averages are available. Therefore, seasonal trends are available
for only a small sample of sites, which makes a seasonal pattern difficult to discern at this time.
The first program-year with a full year's worth of acrolein measurements is 2006. For
sites with at least three valid seasonal averages, it appears that summer and autumn more
commonly exhibited the highest averages, while winter exhibited the least. Every valid seasonal
average of acrolein exceeded the ATSDR intermediate MRL, which is indicated by the dashed
line.
3-79
-------
3.3 Additional Site-Specific Analyses
In addition to many of the analyses described in the preceding sections, the state-specific
sections (4.0 through 31.0) contain additional analyses that are applicable at a local level. This
section provides an overview of these analyses but does not discuss their results. Results of
these site-specific analyses are presented in the state-specific sections.
3.3.1 Emission Tracer Analysis
In this analysis, pollution roses for each of the site-specific pollutants of interest that
exceeded the acute risk factors were created to help identify the geographical area where the
emission sources of these pollutants may have originated. A pollution rose is a plot of the
ambient concentration versus the unit vector of the wind direction; high concentrations are
shown in relation to the direction of potential emissions sources.
3.3.2 Back Trajectory Analysis
A back trajectory analysis traces the origin of an air parcel in relation to the location
where it is currently being measured. The method of constructing a back trajectory uses the
Lagrangian frame of reference. In simplest terms, an air parcel can be traced back one hour to a
new point of reference based on the current measured wind speed and direction. At this new
point of reference (that is now one hour prior to the current observation), the wind speed and
direction are used again to determine where the air was one hour before. Each time segment is
referred to as a "time step." Typical back trajectories go 24 to 48 hours prior using surface and
upper air meteorological observations. Back trajectory calculations are also governed by other
meteorological parameters, such as pressure and temperature.
Gridded meteorological data and the model used for back trajectory analyses were
prepared and developed by the National Oceanic and Atmospheric Administration (NOAA)
using data from the National Weather Service (NWS) and other cooperative agencies. The
model used is the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) (Draxler,
R.R. and Rolph, G.D., 2003). The meteorological data represented the 2006 sampling year.
Back trajectories were computed 24 hours prior to the sampling day (to match the 24-hour
3-80
-------
sample), and composite back trajectory maps were constructed for sampling days using GIS
software. Trajectories are modeled with an initial height of 250 meters above ground level
(AGL). The value of the composite back trajectory map is the determination of a 24-hour
airshed domain for each site. An airshed domain is the geographical area surrounding a site from
which an air parcel may typically travel within the 24-hour time frame. Agencies can use the
airshed domain to evaluate regions where long-range transport may affect their monitoring site.
3.3.3 Wind Rose Analysis
In this analysis, wind roses were constructed for each site to help identify the
predominant direction from which the wind blows. A wind rose shows the frequency of wind
directions about a 16-point compass, and uses color or shading to represent wind speeds. Wind
roses are constructed by uploading hourly surface wind data from the nearest weather station into
a wind rose software program, WRPLOT (Lakes, 2006). A wind rose is often used in
determining where to put an ambient monitoring site when trying to capture emissions from an
upwind source. A wind rose may also be useful in determining whether high concentrations
correlate with a specific wind direction. While the composite back trajectory maps show where
a parcel of air originated from on a number of days, the wind rose shows the frequency at which
wind speed and direction are measured near the monitoring site. In other words, the back
trajectory map focuses on long range transport, while the wind rose captures day-to-day
fluctuations at the surface. Both are used to identify potential meteorological influences on the
monitoring sites.
3.3.4 Site Trends Analysis
Table 2-3 presented past UATMP participation for sites participating in this year's
program. For sites that participated prior to 2005 and were still participating through the 2006
program year, a trends analysis was conducted. The determination of trends are based on daily
average concentrations (refer to the definitions in Section 3.1.5) at each site for three pollutants:
1,3-butadiene, benzene, and formaldehyde. These daily average concentrations are presented in
the form of bar graphs with confidence intervals, represented by error bars extending from the
top of each bar graph. The purpose of the confidence interval is to show the statistical
significance of the relative increases or decreases shown over the years of participation.
3-81
-------
Although the average concentration for a particular year may appear to be much lower (or
higher) than another year, if the confidence intervals overlap, the difference is not statistically
significant. A large confidence interval correlates to a low confidence in a specific statistical
parameter, in this case the daily average concentrations, and may indicate the presence of
outliers driving the daily average in one direction or another. Not all sites sample the same
pollutant types, therefore all three pollutants may not be represented for all years of
participation.
At sites where the pollutants were sampled for at least three consecutive years,
formaldehyde consistently measured the highest daily average concentration, while 1,3-
butadiene consistently measured the lowest. The site with the most years of participation is
CANJ, having sampled continuously since 1994.
3.3.5 Chronic Risk Assessment
A chronic risk assessment was completed for the pollutants that failed at least one risk
screen at each site, and where the annual average concentrations were available. An annual
average includes all measured detections and 1/2 MDL substituted values for non-detects.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Exceptions to this include the Texas and
Alabama sites, for which the sampling period for these sites has been adjusted to account for
their mid-calendar year start and stop dates. Therefore, the start and stop date criteria for a valid
annual average has also been adjusted accordingly.
Theoretical cancer and noncancer risks are calculated by applying the applicable cancer
unit risk estimates (URE) and/or noncancer reference concentrations (RfC) to the annual average
concentration. Cancer risk is defined as the likelihood of developing cancer as a result of
exposure over a 70-year period, and is presented as the number of people at risk for cancer per
million people (EPA, 2006c). The cancer risks presented in this report predict the cancer risk
due to exposure at the annual average level over a 70-year period, not the risk resulting from
exposure over the time period covered in this report. Noncancer risk is presented as the
Noncancer Hazard Quotient (HQ). Noncancer health effects include conditions such as asthma.
3-82
-------
An HQ less than one indicates no chance of developing noncancer effects through lifetime
exposure, while an HQ greater than one indicates that developing a noncancerous health effect is
possible (EPA, 2006c). Annual averages and theoretical risk calculations are presented in each
of the following subsections, where applicable.
In February 2006, the EPA released the results of its national-scale air toxics assessment,
NAT A, for base year 1999 (EPA, 2006c). NAT A uses the NEI for HAP as its starting point, but
also incorporates ambient monitoring data, geographic information, and chemical/physical
transformation information to model ambient concentrations at the census tract level. These
concentrations are then applied to cancer URE and noncancer RfC factors to yield census tract-
level cancer and noncancer risk. The NATA is a useful resource in helping federal and
state/local/tribal agencies identify potential areas of air quality concern.
Several of the program-level pollutants of interest are HAP that have been identified as
NATA risk driver pollutants (EPA, 2006c):
• acrolein (national noncancer);
• arsenic (regional cancer and noncancer);
• benzene (national cancer);
• 1,3-butadiene (regional cancer and noncancer);
• carbon tetrachloride (regional cancer);
• formaldehyde (regional noncancer);
• manganese (regional noncancer);
• nickel (regional noncancer); and
• tetrachloroethylene (regional cancer).
Data from EPA's 1999 NATA were retrieved and are also presented in this data analysis.
First, each site's respective census tract is identified and the percent of the home county
population that resides in said census tract is calculated. Then the NATA-modeled cancer and
3-83
-------
noncancer risk and modeled concentration associated with the pollutants that failed screens at
each site is presented and discussed. NATA-modeled concentrations are assumed to be the
average concentration that a person breathed for an entire year. Although EPA does not
recommend comparing concentrations from different base years, it is useful to see if the
concentration profile is similar.
3.3.6 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk assessment discussed above, each state section also
contains a summary of toxicity-weighted, county-level emissions based on an EPA-approved
approach (EPA, 2007d). A pollutant emitted in high quantities does not necessarily present a
higher risk to human health than a pollutant emitted in very low quantities. The more toxic the
pollutant, the more risk associated with its emissions in ambient air. In order to assign weight to
the emissions based on the toxicity of a given pollutant rather than quantity emitted, the cancer
URE and noncancer RfC discussed above are applied to pollutant-specific emissions at the
county-level. The ten pollutants with the highest emissions in each site's home county will be
presented in each state section, and will be compared to the ten highest toxicity-weighted
emissions. While the absolute magnitude of the toxicity-weighted emissions is not meaningful,
the relevant magnitude of toxicity-weighted emissions to one another is very meaningful in
identifying potential pollutants of interest. In addition, those pollutants exhibiting the ten highest
cancer risks based on the 2006 sampling year's concentrations will also be presented. The
pollutants sampled at each site varied based on the purpose behind the monitoring. This data
analysis may help state, local, and tribal agencies better understand which pollutants emitted,
from a toxicity basis, are of the greatest concern.
3-84
-------
4.0 Sites in Alabama
This section presents meteorological, concentration, and spatial trends for the UATMP
sites in Alabama (ETAL, NBAL, PVAL, and SIAL), located in or near the Birmingham area.
Figures 4-1 thru 4-4 are topographical maps showing the monitoring sites in their urban and rural
locations. Figures 4-5 thru 4-6 identify point source emission locations within 10 miles of each
site as reported in the 2002 NEI for point sources. As Figure 4-5 shows, the three monitoring
sites located within the city of Birmingham (ETAL, NBAL, and SIAL) are located relatively
close to each other. Both the sites and nearby facilities are oriented along a diagonal line
extending from northeast to southwest Birmingham. Surface coating processes, waste treatment
and disposal operations, and fuel combustion facilities are the most prevalent industries near
these monitoring sites. The PVAL monitoring site is located on the western edge of Jefferson
County, with relatively few industrial sources nearby.
Sites sampling in the Birmingham, Alabama area were funded to sample for one year,
beginning in the summer of 2005 and continuing through the summer of 2006, though the start
and end dates vary slightly from site-to-site. In order to facilitate data analysis, the entire dataset
for the one year of sampling for these sites is included.
Birmingham, Alabama is about 300 miles inland from the Gulf of Mexico. This
proximity allows the Gulf of Mexico to be a major influence in the city's climate. Winters are
tempered and wet while summers are warm and humid. The area enjoys fairly ample
precipitation (Ruffner and Bair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2005 and 2006. These data were used to determine how meteorological conditions on sampling
days vary from normal conditions throughout the year. They were also used to calculate
correlations of meteorological data with ambient air concentration measurements. The weather
station closest to the ETAL, NBAL, and SIAL monitoring sites is Birmingham International
Airport (WBAN 13876), while the closest weather station to PVAL is Tuscaloosa Municipal
Airport (WBAN 93806). Table 4-1 presents average meteorological conditions of temperature
4-1
-------
Figure 4-1. Birmingham, Alabama (ETAL) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
4-2
-------
Figure 4-2. Birmingham, Alabama (NBAL) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
4-3
-------
Figure 4-3. Birmingham, Alabama (PVAL) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
4-4
-------
Figure 4-4. Birmingham, Alabama (SIAL) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
4-5
-------
Figure 4-5. Facilities Located Within 10 Miles of ETAL, NBAL, and SIAL
f
-f o
"Shelby
County
Legend
ETAL UATMP site
NBAL UATMP site
SIAL UATMP site
10 mile radius
Note; Due to faculty density and collocation, the total facilities
displayed may not represent all facilities within the area of interest.
County boundary
Source Category Group (No. of Facilities)
¥ Automotive Repair, Services. & Parking (1)
Business Services Facility (1)
C Chemicals & Allied Products Facility (1)
E Electric. Gas, & Sanitary Services (1)
D Fabricated Metal Products Facility (10)
f Fuel Combustion Industrial Facility (11)
H Furniture 8 Fixtures Facility (2)
+ Health Services Facility (1)
»- Integrated Iron S Steel Manufacturing Facility (5)
i Liquids Distribution Industrial Facility (1)
s Lumbers Wood Products Facility (1)
0 Medical. Dental S Hospital Equipment and Supplies (1 )
B Mineral Products Processing Industrial Facility (4)
p Miscellaneous Processes Industrial Facility (3)
\ Non-ferrous Metals Processing Industrial Facility (3)
2 Nonmetallic Minerals, Except Fuels (2)
° Personal Services (1)
p Petroleum/Nat. Gas Prod. & Refining Industrial Facility (1)
v Polymers S Resins Production Industrial Facility (2)
° Primary Metal Industries Facility (3)
* Production of Inorganic Chemicals Industrial Facility (1)
4 Production of Organic Chemicals Industrial Facility {1}
s Surface Coating Processes Industrial Facility {19}
T Transportation Equipment (1)
' Waste Treatment & Disposal Industrial Facility (11)
r Wholesale Trade (2)
4-6
-------
Figure 4-6. Facilities Located Within 10 Miles of PVAL
/ F
Tuscaloosa
County
Jefferson
County
Note: Due to facility density and collocation, the total facilities
displayed may nof represent all facilities wilhirt the area of interest.
Legend
TV PVAL UATMP site
10 mile radius
| County boundary
Source Category Group (No. of Facilities)
t Coal Mining (1)
F Fuel Combustion Industrial Facility (3)
8 Utility Boilers (1)
4-7
-------
Table 4-1. Average Meteorological Conditions near the Monitoring Sites in Alabama
Site
ETAL
NBAL
PVAL
SIAL
WBAN
13876
13876
93806
13876
Average
Type
2005-
2006
Sampling
Day
2005-
2006
Sampling
Day
2005-
2006
Sampling
Day
2005-
2006
Sampling
Day
Average
Maximum
Temperature
(OF)
74.31
±1.55
75.26
±4.24
74.31
±1.55
76.90
±4.25
76.38
±1.52
79.24
±4.06
74.31
±1.55
76.76
±4.09
Average
Temperature
(°F)
64.18
±1.52
64.85
±4.36
64.18
±1.52
66.33
±4.31
64.65
±1.49
66.92
±4.08
64.18
± 1.52
66.24
±4.19
Average
Dew Point
Temperature
(»F)
51.24
±1.70
51.00
±4.89
51.24
±1.70
51.92
±4.66
53.29
±1.67
54.95
±4.56
51.24
±1.70
52.28
±4.71
Average
Wet Bulb
Temperature
(°F)
57.16
±1.45
57.32
±4.16
57.16
±1.45
58.32
±4.02
58.39
±1.45
60.12
±3.96
57.16
±1.45
58.51
±3.98
Average
Relative
Humidity
(%)
66.47
±1.30
64.83
±4.28
66.47
± 1.30
63.74
±4.01
70.23
±1.08
69.39
±3.07
66.47
±1.30
64.81
±4.43
Average
Sea Level
Pressure
(mb)
1017.79
±0.53
1017.70
±1.53
1017.79
±0.53
1017.70
±1.41
1017.48
±0.53
1017.26
±1.45
1017.79
±0.53
1017.27
±1.62
Average
Scalar Wind
Speed
(kt)
5.32
±0.28
5.31
±0.91
5.32
±0.28
5.29
±0.85
4.53
±0.25
4.39
±0.85
5.32
±0.28
5.47
±0.95
oo
-------
(average maximum and average), moisture (average dew point temperature, average wet bulb
temperature, and average relative humidity), pressure (average sea level pressure), and wind
information (average scalar wind speed) for the July 2005 to June 2006 time frame (to capture an
entire year closely corresponding to the sampling duration for the Alabama sites) and on days
samples were collected. Also included in Table 4-1 is the 95 percent confidence interval for
each parameter. As shown in Table 4-1, average meteorological conditions on sampling days
were fairly representative of average weather conditions throughout the year.
4.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Alabama
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. Table 4-2 presents the pollutants that failed
at least one screen at the Alabama monitoring sites. The Alabama sites sampled for carbonyls,
VOCs, SVOCs, and metals (NBAL sampled for TSP and PMio while the other Alabama sites
sampled TSP only).
The following observations are shown in Table 4-2:
• The number of pollutants failing the screen varies by site.
• 19 pollutants with a total of 360 measured concentrations failed the screen at ETAL.
• 29 pollutants with a total of 458 measured concentrations failed the screen at NBAL.
• 12 pollutants with a total of 208 measured concentrations failed the screen at PVAL.
• 25 pollutants with a total of 376 measured concentrations failed the screen at SIAL.
• The pollutants of interest also varied by site, yet the following 10 pollutants
contributed to the top 95 percent of the total failed screens at each Alabama
monitoring site: arsenic (TSP), acrolein, formaldehyde, carbon tetrachloride,
4-9
-------
Table 4-2. Comparison of Measured Concentrations and EPA Screening Values for
the Alabama Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
East Thomas, Birmingham, Alabama - ETAL
Arsenic (TSP)
Manganese (TSP)
Naphthalene
Formaldehyde
Carbon Tetrachloride
Benzene
Acetaldehyde
1,3 -Butadiene
£>-Dichlorobenzene
Tetrachloroethylene
Acrolein
Nickel (TSP)
Hexachloro- 1 ,3 -butadiene
Cadmium (TSP)
Xylenes
Benzo (a) pyrene
Hexavalent Chromium
Acrylonitrile
Ethyl Aery late
Total
31
31
31
31
31
31
31
29
29
20
17
11
10
9
9
4
o
J
1
1
360
31
31
31
31
31
31
31
30
29
25
17
31
10
31
31
26
26
1
1
475
100.00
100.00
100.00
100.00
100.00
100.00
100.00
96.67
100.00
80.00
100.00
35.48
100.00
29.03
29.03
15.38
11.54
100.00
100.00
75.79
8.61
8.61
8.61
8.61
8.61
8.61
8.61
8.06
8.06
5.56
4.72
3.06
2.78
2.50
2.50
1.11
0.83
0.28
0.28
8.61
17.22
25.83
34.44
43.06
51.67
60.28
68.33
76.39
81.94
86.67
89.72
92.50
95.00
97.50
98.61
99.44
99.72
100.00
North Birmingham, Alabama - NBAL
Carbon Tetrachloride
Arsenic (PM10)
Benzene
£>-Dichlorobenzene
Acetaldehyde
Manganese (TSP)
Arsenic (TSP)
Naphthalene
Formaldehyde
Manganese (PM10)
1,3 -Butadiene
Acrolein
Tetrachloroethylene
Cadmium (TSP)
Cadmium (PM10)
Xylenes
Nickel (TSP)
Benzo (a) pyrene
Hexachloro- 1 ,3 -butadiene
31
31
31
31
31
31
31
30
29
27
25
22
17
16
14
11
9
9
6
31
31
31
31
31
31
31
31
31
31
25
22
23
31
31
31
31
23
6
100.00
100.00
100.00
100.00
100.00
100.00
100.00
96.77
93.55
87.10
100.00
100.00
73.91
51.61
45.16
35.48
29.03
39.13
100.00
6.77
6.77
6.77
6.77
6.77
6.77
6.77
6.55
6.33
5.90
5.46
4.80
3.71
3.49
3.06
2.40
1.97
1.97
1.31
6.77
13.54
20.31
27.07
33.84
40.61
47.38
53.93
60.26
66.16
71.62
76.42
80.13
83.62
86.68
89.08
91.05
93.01
94.32
4-10
-------
Table 4-2. Comparison of Measured Concentrations and EPA Screening Values for
the Alabama Monitoring Sites (Continued)
Pollutant
Benzo (a) anthracene
Hexavalent Chromium
Dibenz (a,h) anthracene
Nickel (PM10)
Benzo (b) fluoranthene
Benzo (k) fluoranthene
Trichloroethylene
1 ,2-Dichloroethane
Indeno(l,2,3-cd)pyrene
Acrylonitrile
Total
#of
Failures
5
5
4
3
o
J
2
1
1
1
1
458
#of
Measured
Detections
30
24
13
31
28
29
14
1
22
1
726
%of
Screens
Failed
16.67
20.83
30.77
9.68
10.71
6.90
7.14
100.00
4.55
100.00
63.09
% of Total
Failures
1.09
1.09
0.87
0.66
0.66
0.44
0.22
0.22
0.22
0.22
Cumulative
%
Contribution
95.41
96.51
97.38
98.03
98.69
99.13
99.34
99.56
99.78
100.00
Providence, Alabama - PVAL
Benzene
Carbon Tetrachloride
Acetaldehyde
Arsenic (TSP)
Formaldehyde
Manganese (TSP)
£>-Dichlorobenzene
Acrolein
Hexachloro- 1 ,3 -butadiene
Naphthalene
1,3 -Butadiene
Acrylonitrile
Total
31
31
29
29
27
19
19
10
5
5
2
1
208
31
31
31
31
31
31
27
10
5
31
9
1
269
100.00
100.00
93.55
93.55
87.10
61.29
70.37
100.00
100.00
16.13
22.22
100.00
77.32
14.90
14.90
13.94
13.94
12.98
9.13
9.13
4.81
2.40
2.40
0.96
0.48
14.90
29.81
43.75
57.69
70.67
79.81
88.94
93.75
96.15
98.56
99.52
100.00
Sloss Industries, Birmingham, Alabama - SIAL
Carbon Tetrachloride
Acetaldehyde
Arsenic (TSP)
Manganese (TSP)
Benzene
Formaldehyde
£>-Dichlorobenzene
Naphthalene
1,3 -Butadiene
Acrolein
Benzo (a) pyrene
Tetrachloroethylene
Nickel (TSP)
Hexavalent Chromium
Dibenz (a,h) anthracene
Hexachloro- 1 ,3 -butadiene
31
31
31
31
31
31
30
30
28
19
16
15
11
7
6
6
31
31
31
31
31
31
31
31
28
19
27
22
31
23
21
6
100.00
100.00
100.00
100.00
100.00
100.00
96.77
96.77
100.00
100.00
59.26
68.18
35.48
30.43
28.57
100.00
8.24
8.24
8.24
8.24
8.24
8.24
7.98
7.98
7.45
5.05
4.26
3.99
2.93
1.86
1.60
1.60
8.24
16.49
24.73
32.98
41.22
49.47
57.45
65.43
72.87
77.93
82.18
86.17
89.10
90.96
92.55
94.15
4-11
-------
Table 4-2. Comparison of Measured Concentrations and EPA Screening Values for
the Alabama Monitoring Sites (Continued)
Pollutant
Beryllium (TSP)
Cadmium (TSP)
Xylenes
Chloromethylbenzene
Benzo (k) fluoranthene
Benzo (a) anthracene
Indeno(l,2,3-cd)pyrene
Benzo (b) fluoranthene
Acrylonitrile
Total
#of
Failures
6
4
4
3
376
#of
Measured
Detections
31
31
31
3
30
31
25
29
1
637
%of
Screens
Failed
19.35
12.90
12.90
100.00
3.33
3.23
4.00
3.45
100.00
59.03
% of Total
Failures
1.60
1.06
1.06
0.80
0.27
0.27
0.27
0.27
0.27
Cumulative
%
Contribution
95.74
96.81
97.87
98.67
98.94
99.20
99.47
99.73
100.00
manganese (TSP), acetaldehyde, benzene, naphthalene, hexachloro-l,3-butadiene,and
/7-dichlorobenzene. If PVAL is not included, the list of pollutants of interest is even
longer.
Of the 10 pollutants that were the same among all four sites, four pollutants of interest
(acrolein, benzene, carbon tetrachloride, and hexachloro-1,3-butadiene) had 100
percent of their measured detections fail screens.
4.2
Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average can be calculated. The seasonal average includes 1/2
MDLs substituted for all non-detects. A seasonal average will not be calculated for pollutants
with less than seven measured detections in a respective season. The seasons presented for
Alabama will be autumn 2005 through spring 2006 rather than winter through autumn in order to
accommodate their summer to summer sampling schedule (a summer 2005 and summer 2006
seasonal average will not be possible due to the low number of samples compared to the
detection criteria). Finally, the annual average is the average concentration of all measured
detections and 1/2 MDLs substituted for non-detects. The resulting daily averages may therefore
be inherently higher than the annual averages where 1/2 MDLs replacing non-detects are
incorporated into the average. Annual averages were calculated for monitoring sites where
4-12
-------
sampling began no later than February and ended no earlier than November for most sites.
However, this time period was adjusted for the Alabama sites to accommodate their summer to
summer sampling schedule. The daily and seasonal averages are presented in Table 4-3.
Because a full summer of sampling was not conducted at the sites, summer averages (both 2005
and 2006) could not be calculated and are therefore not shown in Table 4-3. Annual averages are
presented and discussed in further detail in later sections.
The following observations for ETAL are shown in Table 4-3:
• Among the daily averages, total xylenes had the highest concentration by mass (7.57
± 1.89 |ig/m3), followed by formaldehyde (4.90 ± 0.76 |ig/m3) and benzene (2.90 ±
0.65 |ig/m3).
• Most of the seasonal averages of the pollutants of interest did not vary much from
season-to-season, when the confidence interval is considered. One exception to this
was/>-dichlorobenzene. The autumn average (0.44 ± 0. 15 |ig/m3) was more than
twice the winter average (0. 19 ± 0.05 |ig/m3). Unfortunately, this site did not have a
valid spring />-dichlorobenzene concentration for comparison.
The following observations for NBAL are shown in Table 4-3:
• Similar to ETAL, the pollutants with the highest daily averages for NBAL were total
xylenes (9.66 ± 2.88 |ig/m3), formaldehyde (4.17 ± 0.89 |ig/m3), and benzene (3.17 ±
• No autumn averages could be calculated for NBAL for VOC and carbonyl
compounds due to a brief gap in sampling.
• Most of the seasonal averages of the pollutants of interest did not vary much from
season-to-season, when the confidence interval was considered. One exception to
this was formaldehyde. The spring average (4.04 ± 1.25 |ig/m3) was more than twice
the winter average (2.06 ± 0.66 |ig/m3).
The following observations for PVAL are shown in Table 4-3:
• The pollutants with the highest daily averages were formaldehyde (4. 14 ±
2.06 |ig/m3), acetaldehyde (1.49 ± 0.82 |ig/m3), and acrolein (0.68 ± 0.46 |ig/m3).
• Most of the seasonal averages of the pollutants of interest did not vary much from
season-to-season, when the confidence interval was considered.
4-13
-------
Table 4-3. Daily and Seasonal Averages for the Pollutants of Interest for the Alabama Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Average
(jig/m3)
Confidence
Int.
Autumn 2005
Average
(jig/m3)
Confidence
Int.
Winter 2005/2006
Average
(jig/m3)
Confidence
Int.
Spring 2006
Average
(jig/m3)
Confidence
Int.
East Thomas, Birmingham, Alabama - ETAL
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic
Benzene
Cadmium (TSP)
Carbon Tetrachloride
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese (TSP)
Naphthalene
Nickel (TSP)
£>-Dichlorobenzene
Tetrachloroethylene
Xylenes
30
31
17
31
31
31
31
31
10
31
31
31
29
25
31
31
31
30
31
31
31
31
31
31
31
31
31
31
31
31
0.26
1.99
0.95
0.01
2.90
O.01
0.68
4.90
0.17
0.05
0.27
0.01
0.29
0.45
7.57
0.06
0.27
0.31
0.01
0.65
O.01
0.04
0.76
0.03
0.01
0.09
0.01
0.06
0.12
1.89
0.25
2.28
NR
0.01
4.03
O.01
0.68
4.42
NR
0.06
0.37
0.01
0.44
0.45
10.33
0.13
0.71
NR
0.01
1.86
O.01
0.07
1.21
NR
0.02
0.25
0.01
0.15
0.23
4.51
0.28
1.60
NR
0.01
2.74
O.01
0.62
3.33
NR
0.04
NR
0.01
0.19
NR
7.09
0.10
0.27
NR
0.01
0.88
O.01
0.08
0.58
NR
0.02
NR
0.01
0.05
NR
2.56
NR
2.00
NR
0.01
2.30
O.01
0.66
5.30
NR
0.06
0.25
0.01
NR
NR
6.81
NR
0.53
NR
0.01
0.91
O.01
0.05
1.27
NR
0.03
0.13
0.01
NR
NR
4.35
North Birmingham, Alabama - NBAL
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (PM10)
Arsenic (TSP)
Benzene
Benzo (a) anthracene
Benzo (a) pyrene
Cadmium (TSP)
Cadmium (PM10)
Carbon Tetrachloride
Formaldehyde
Hexachloro- 1 ,3 -butadiene
25
31
22
31
31
31
30
23
31
31
31
31
6
31
31
31
31
31
31
31
31
31
31
31
31
31
0.17
1.65
0.90
0.00
0.00
3.17
O.01
0.01
0.01
O.01
0.67
4.17
0.19
0.05
0.25
0.20
0.01
O.01
1.17
O.01
0.01
0.01
O.01
0.05
0.89
0.03
NR
NR
NR
0.01
O.01
NR
0.01
NR
0.01
O.01
NR
NR
NR
NR
NR
NR
0.01
O.01
NR
O.01
NR
0.01
O.01
NR
NR
NR
NR
1.17
0.79
0.01
O.01
2.08
O.01
NR
0.01
O.01
0.66
2.06
NR
NR
0.26
0.33
0.01
O.01
0.91
O.01
NR
0.01
O.01
0.11
0.66
NR
0.17
1.65
0.63
0.01
O.01
3.76
O.01
NR
0.01
O.01
0.59
4.04
NR
0.11
0.51
0.16
0.01
O.01
2.79
O.01
NR
0.01
O.01
0.04
1.25
NR
-------
Table 4-3. Daily and Seasonal Averages for Pollutants of Interest for the Alabama Monitoring Sites (Continued)
Pollutant
Hexavalent Chromium
Manganese (PM10)
Manganese (TSP)
Naphthalene
Nickel (TSP)
£>-Dichlorobenzene
Tetrachloroethylene
Xylenes
#of
Measured
Detections
24
31
31
31
31
31
23
31
#of
Samples
31
31
31
31
31
31
31
31
Daily
Average
(jig/m3)
<0.01
0.04
0.07
0.29
0.01
0.32
0.31
9.66
Confidence
Interval
O.01
0.01
0.02
0.09
0.01
0.06
0.09
2.88
Autumn 2005
Average
(Ug/m3)
NR
0.05
0.10
0.30
0.01
NR
NR
NR
Confidence
Interval
NR
0.02
0.05
0.16
0.01
NR
NR
NR
Winter 2005/2006
Average
(jig/m3)
NR
0.02
0.05
0.24
0.01
0.26
NR
7.74
Confidence
Interval
NR
0.01
0.03
0.12
0.01
0.06
NR
6.05
Spring 2006
Average
(jig/m3)
NR
0.04
0.08
0.20
0.01
0.24
NR
9.95
Confidence
Interval
NR
0.02
0.05
0.15
0.01
0.08
NR
5.84
Providence, Alabama - PVAL
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
Carbon Tetrachloride
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese (TSP)
Naphthalene
£>-Dichlorobenzene
31
10
31
31
31
31
5
31
31
27
31
30
31
31
31
31
31
31
31
31
1.49
0.68
O.01
0.57
0.65
4.14
0.19
0.01
0.02
0.25
0.82
0.46
O.01
0.10
0.05
2.06
0.04
O.01
0.01
0.08
1.29
NR
O.01
0.61
0.71
3.14
NR
0.01
0.01
0.27
0.26
NR
O.01
0.12
0.08
1.07
NR
O.01
0.01
0.04
0.74
NR
O.01
0.62
0.56
1.11
NR
O.01
0.02
0.15
0.24
NR
O.01
0.20
0.12
0.42
NR
O.01
0.01
0.03
2.64
NR
O.01
0.55
0.61
6.67
NR
0.01
0.01
NR
3.00
NR
O.01
0.29
0.08
7.21
NR
O.01
0.01
NR
Sloss Industries, Birmingham, Alabama - SIAL
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
Benzo (a) pyrene
Beryllium (TSP)
Carbon Tetrachloride
Dibenz (a,h) anthracene
Formaldehyde
28
31
19
31
31
27
31
31
21
31
31
31
31
31
31
31
31
31
31
31
0.23
1.55
1.15
0.01
6.17
0.01
O.01
0.65
O.01
3.70
0.05
0.19
0.43
O.01
2.07
0.01
O.01
0.04
O.01
0.71
NR
1.61
NR
0.01
NR
NR
O.01
NR
NR
3.09
NR
0.33
NR
0.01
NR
NR
O.01
NR
NR
0.64
0.26
1.24
NR
0.01
7.55
NR
O.01
0.56
NR
2.31
0.12
0.26
NR
O.01
7.45
NR
O.01
0.07
NR
0.72
0.20
1.69
NR
0.01
4.79
0.01
O.01
0.64
NR
4.03
0.08
0.39
NR
0.01
2.13
0.01
O.01
0.07
NR
1.17
-------
Table 4-3. Daily and Seasonal Averages for Pollutants of Interest for the Alabama Monitoring Sites (Continued)
Pollutant
Hexachloro- 1 ,3 -butadiene
Hexavalent Chromium
Manganese (TSP)
Naphthalene
Nickel (TSP)
£>-Dichlorobenzene
Tetrachloroethylene
#of
Measured
Detections
6
23
31
31
31
31
22
#of
Samples
31
32
31
31
31
31
31
Daily
Average
(jig/m3)
0.18
<0.01
0.14
0.50
<0.01
0.40
0.32
Confidence
Interval
0.04
<0.01
0.05
0.12
<0.01
0.11
0.09
Autumn 2005
Average
(Hg/m3)
NR
NR
0.15
0.44
0.01
NR
NR
Confidence
Interval
NR
NR
0.13
0.23
0.01
NR
NR
Winter 2005/2006
Average
(jig/m3)
NR
NR
0.07
NR
0.01
0.27
NR
Confidence
Interval
NR
NR
0.02
NR
0.01
0.05
NR
Spring 2006
Average
(jig/m3)
NR
O.01
0.14
0.56
0.01
0.29
NR
Confidence
Interval
NR
O.01
0.09
0.27
0.01
0.12
NR
NA = Not Available due to short sampling duration.
NR = Not Reportable due to low number of measured detections.
-------
• One exception to this was/>-dichlorobenzene. The autumn average (0.27 ± 0.04
|ig/m3) was more than the winter average (0.15 ± 0.03 |ig/m3). Unfortunately, th
site did not have a valid spring/>-dichlorobenzene concentration for comparison.
• The spring formaldehyde and acetaldehyde averages were significantly higher than
the other seasons. However, the confidence intervals were also very large, indicating
that these averages may be impacted by outliers. Relatively high concentrations of
these pollutants were measured on April 17, 2006.
The following observations for SIAL are shown in Table 4-3:
• The pollutants with the highest daily averages were benzene (6.17 ± 2.07 jig/m3),
formaldehyde (3.70 ± 0.71 |ig/m3), and acetaldehyde (1.55 ± 0.19 |ig/m3).
• No autumn averages could be calculated for SIAL for VOC and carbonyl compounds
due to a few invalid samples.
• Most of the seasonal averages of the pollutants of interest did not vary much from
season-to-season, when the confidence interval was considered.
The winter benzene average was significantly higher than the spring average. However,
the confidence intervals were also very large, indicating that this average may be impacted by
outliers. A relatively high concentration of benzene was measured on February 4, 2006.
4.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for Alabama monitoring sites was evaluated
using ATSDR short-term (acute) and intermediate MRL and California EPA acute REL factors.
Acute risk is defined as exposures from 1 to 14 days while intermediate risk is defined as
exposures from 15 to 364 days. It is useful to compare preprocessed daily measurements to the
short term MRL and REL factors, as well as compare seasonal averages to the intermediate
MRL. Of the pollutants with at least one failed screen at the Alabama sites, only acrolein and
benzene exceeded either the acute or intermediate risk values, and each site's non-chronic risk is
summarized in Table 4-4.
The following observations about acrolein are shown in Table 4-4:
• All acrolein measured detections at the Alabama sites were greater than the ATSDR
acute MRL (0.11 |ig/m3) and most were greater than the California REL (0.19 |ig/m3).
4-17
-------
Table 4-4. Non-Chronic Risk Summary for the Alabama Monitoring Sites
Site
ETAL
NBAL
PVAL
SIAL
SIAL
Method
TO- 15
TO- 15
TO- 15
TO- 15
TO- 15
Pollutant
Acrolein
Acrolein
Acrolein
Acrolein
Benzene
Daily
Average
(Hg/m3)
0.95 ±
0.31
0.90 ±
0.20
0.68 ±
0.46
1.15±
0.43
6.17 ±
2.07
ATSDR
Short-term
MRL
(Hg/m3)
0.11
0.11
0.11
0.11
28.75
# of ATSDR
MRL
Exceedances
17
22
10
19
1
CAL EPA
REL Acute
(Hg/m3)
0.19
0.19
0.19
0.19
—
# of CAL
EPA REL
Exceedances
16
22
8
19
—
ATSDR
Intermediate-
term MRL
(Hg/m3)
0.09
0.09
0.09
0.09
20
Autumn
2005
Average
(Hg/m3)
NR
NR
NR
NR
NR
Winter
2006
Average
(Hg/m3)
NR
0.79 ±
0.33
NR
NR
7.55 ±
7.45
Spring
2006
Average
(Hg/m3)
NR
0.63 ±
0.16
NR
NR
4.79 ±
2.13
NA = Not Available due to short sampling duration.
NR = Not Reportable due to low number of measured detections.
00
-------
• The average daily concentration ranged from 0.68 ± 0.46 |ig/m3 (for PVAL) to 1.15 ±
0.43 |ig/m3 (for SIAL).
• Few seasonal averages of acrolein could be calculated, due to the low number of
measured detections in each season.
• NBAL had both a winter and spring acrolein average. Both were an order of
magnitude greater than the ATSDR intermediate MRL (0.09 |ig/m3).
The following observations about benzene are shown in Table 4-4:
• One benzene measured detection at the SIAL site was greater than the ATSDR acute
risk value of 28.75 |ig/m3.
• The average daily benzene concentration was 6.17 ± 2.07 |ig/m3, and none of the
valid seasonal averages exceeded the ATSDR intermediate MRL of 20 |ig/m3.
• As previously mentioned, autumn seasonal averages could not be calculated for the
SIAL site.
• The exceedance of the ATSDR acute value occurred on February 4, 2006. The winter
2006 benzene average had a large confidence interval, indicating that the average
may be impacted by outliers.
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of
concentration and wind direction. Acrolein concentrations exceeded the acute risk factors at all
four Alabama monitoring sites, and benzene exceeded the acute risk factor at SIAL. Figures 4-7
through 4-11 are pollution roses for acrolein and/or benzene for the Alabama sites. As shown in
Figures 4-7 through 4-10, and discussed in Section 4.3, most, if not all, acrolein concentrations
exceeded the acute risk factors, which are indicated by a dashed line (CALEPA REL) and solid
line (ATSDR MRL). Only one benzene concentration exceeded the ATSDR acute MRL, as
shown in Figure 4-11.
Figure 4-7 is the acrolein pollution rose for the ETAL monitoring site and the following
observations can be made:
• Concentrations exceeding the acute risk factors occurred with winds originating from
a variety of directions, which is characteristic of mobile sources.
4-19
-------
Figure 4-7. Acrolein Pollution Rose for ETAL
to
o
3.5
3.0
2.5
2.0
1.5
§ 1.0
IB
ro
| 0.5
01
o
c
O 00
O
c
3 0.5
_3
£ 1.0
1.5
2.0
2.5
3.0
3.5
A n
NW , N
— CA EPA REL (0.19 |jg/m3)
— ATSDR MRL (0.1 1 |jg/m3)
-
-
-
-
-
f
+ <
W A''
* * '4
4
-
-
-
-
-
OlAf O
sw s
NE
•
*
> *
^\ * E
-s,l
W
Dailv Ava Cone =0.95 ± 0.31 ua/m3 SE
3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
Pollutant Concentration
4.0
-------
Figure 4-8. Acrolein Pollution Rose for NBAL
3.0
2.5
2.0
1.5
1.0
o
IB
0.5
01
o
O 0.0
O
NW
W
N
» , *
NE
0.5
O
Q.
1.0
1.5
2.0
2.5
SW
3.0
3.0
— CA EPA REL (0.19 |jg/rrr)
— ATSDRMRL(0.11 M9/m3)
Daily Avg Cone =0.90 ± 0.20 uq/nf
2.5 2.0 1.5 1.0 0.5 0.0 0.5
Pollutant Concentration
1.0
1.5
2.0
2.5
SE
3.0
-------
Figure 4-9. Acrolein Pollution Rose for PVAL
to
to
3.5
3.0
2.5
2.0
1.5
t Concentration
0 0 -^
b 01 b
3 0.5
£ 1.0
1.5
2.0
2.5
3.0
3.5
A n
NW , N
— CA EPA REL (0.19 |jg/m3)
— ATSDR MRL (0.1 1 |jg/m3)
-
-
-
W » » ^
' **^
-
-
-
,
-
-
sw s
NE
"~Sfc ^
DailvAva Cone =0.68 ± 0.46 uq/m3 SE
4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0
Pollutant Concentration
2.5 3.0
3.5
4.0
-------
Figure 4-10. Acrolein Pollution Rose for SIAL
to
o
IB
I
01
o
o
o
4-1
c
$
o
a.
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0 0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
A n
NW N
-
-
-
»
<
W * *},-
* * •
*
-
-
-
-
OlAf O
sw s
, NE
— CA EPA REL (0.1 9 |jg/m3)
— ATSDRMRL(0.11 |jg/m3)
^
•
>
^v * E
"
DailvAva Cone =1.15 ±0.43 uq/m3 SE
3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0
Pollutant Concentration
1.5
2.0 2.5 3.0 3.5
4.0
-------
Figure 4-11. Benzene Pollution Rose for SIAL
to
ATSDRre-calcMRL
30.0
NE
Daily Avg Cone
6.17±2.07uq/m3
SE
30.0 27.0 24.0 21.0 18.0 15.0 12.0 9.0
6.0 3.0 0.0 3.0 6.0
Pollutant Concentration
9.0
12.0 15.0 18.0 21.0 24.0 27.0 30.0
-------
• The highest concentration of acrolein occurred on July 27, 2005 with a westerly wind.
• The ETAL site is located near several heavily traveled roadways, including 1-20,
which runs east to west and lies to the south of the monitoring site. Railroads are also
located to the north and south of the site. A number of industrial facilities are located
within a 10-mile radius of this site.
Figure 4-8 is the acrolein pollution rose for the NBAL monitoring site and the following
observations can be made:
• The pollution rose shows that concentrations exceeding the acute risk factors
occurred with winds originating from a variety of directions, which is characteristic
of mobile sources.
• The highest concentration of acrolein occurred on October 31, 2005 with a south-
southeasterly wind.
• NBAL is located in a commercial, urban part of Birmingham, just east of 1-65, where
several railways transverse the area near the monitoring site. A number of industrial
facilities are located within a few miles of this site.
Figure 4-9 is the acrolein pollution rose for the PVAL monitoring site and the following
observations can be made:
• The few detected concentrations of acrolein were measured on days with winds
originating primarily from a westerly and northwesterly direction.
• The highest concentration of acrolein occurred on October 19, 2005 with a
southwesterly wind.
• The PVAL site is located in a rural area beyond the Birmingham city limits, with few
industrial sources nearby.
Figure 4-10 is the acrolein pollution rose for the SIAL monitoring site and the following
observations can be made:
• Concentrations exceeding the acute risk factors occurred with winds originating from
a variety of directions, characteristic of mobile sources.
• The highest concentrations of acrolein occurred on October 19, 2005 and July 27,
2005, both with a westerly wind.
• These dates correspond with ETAL and PVAL.
4-25
-------
• SIAL is located just east of NBAL, near several heavily traveled roadways. A
number of railways also transverse the area near SIAL. This site is in an urban area
and a number of industrial facilities are located within a few miles of the site.
Figure 4-11 is the benzene pollution rose for the SIAL monitoring site and the following
observations can be made:
• Most concentrations measured at SIAL are well below the ATSDR MRL. Only the
concentration measured on February 4, 2006, which occurred with northwesterly
winds, exceeded the acute risk factor.
• Figure 4-5 shows that there are a few industrial facilities located to the northwest of
the monitoring site.
4.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following three
meteorological data analyses: Pearson correlation coefficients between meteorological
parameters (such as temperature) and the concentrations of the pollutants of interest; sample-year
composite back trajectories; and sample-year wind roses.
4.4.1 Pearson Correlation Analysis
Table 4-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the Alabama monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for ETAL from Table 4-5:
• Most of the correlations between the temperature and moisture variables and the
pollutants of interest were positive, indicating that concentrations tend to increase as
temperature and humidity increase.
• Relative humidity generally did not follow the same trend as the dew point and wet
bulb temperatures.
• Formaldehyde exhibited strong correlations with the temperature variables, which
indicates that concentrations of this pollutant tend to increase as temperature
increases.
4-26
-------
Table 4-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Alabama
Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
East Thomas, Birmingham, Alabama - ETAL
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
Cadmium (TSP)
Carbon Tetrachloride
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese (TSP)
Naphthalene
Nickel (TSP)
£>-Dichlorobenzene
Tetrachloroethylene
Xylenes
30
31
17
31
31
31
31
31
10
31
31
31
29
25
31
-0.09
0.42
0.06
0.34
0.13
0.27
0.27
0.62
-0.37
0.35
0.07
0.19
0.47
-0.15
0.18
-0.16
0.29
0.04
0.24
0.00
0.16
0.29
0.58
-0.49
0.27
-0.05
0.13
0.38
-0.22
0.09
-0.16
0.12
0.14
0.21
0.01
0.14
0.17
0.34
-0.53
0.19
-0.10
0.20
0.38
-0.16
0.16
-0.16
0.19
0.11
0.21
0.00
0.14
0.22
0.44
-0.53
0.21
-0.09
0.18
0.38
-0.19
0.12
-0.02
-0.26
0.27
0.07
0.07
0.05
-0.20
-0.32
-0.23
-0.05
-0.10
0.28
0.19
0.05
0.21
0.12
0.13
0.25
0.28
0.28
0.26
-0.06
0.02
0.83
0.15
0.41
-0.10
-0.03
0.22
0.11
-0.48
-0.63
-0.16
-0.84
-0.65
-0.64
0.10
-0.38
-0.32
-0.58
-0.50
-0.29
-0.53
-0.29
-0.62
North Birmingham, Alabama - NBAL
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (PM10)
Arsenic (TSP)
Benzene
Benzo (a) anthracene
Benzo (a) pyrene
Cadmium (PM10)
Cadmium (TSP)
Carbon Tetrachloride
Formaldehyde
25
31
22
31
31
31
30
23
31
31
31
31
0.15
0.63
-0.08
0.32
0.32
0.10
0.07
0.13
0.37
0.36
0.14
0.81
0.04
0.52
-0.15
0.20
0.21
-0.03
-0.03
0.06
0.30
0.30
0.15
0.77
-0.01
0.34
-0.28
0.15
0.17
-0.12
-0.07
0.03
0.33
0.29
0.03
0.61
0.01
0.42
-0.23
0.16
0.18
-0.08
-0.06
0.04
0.32
0.30
0.07
0.68
-0.06
-0.22
-0.29
0.03
0.05
-0.17
-0.05
0.01
0.20
0.13
-0.23
-0.12
0.35
0.05
0.52
0.17
0.15
0.32
0.20
0.08
0.03
0.03
0.02
-0.07
-0.58
-0.61
-0.35
-0.78
-0.73
-0.51
-0.48
-0.36
-0.52
-0.45
-0.01
-0.43
to
-------
Table 4-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Alabama
Monitoring Sites (Continued)
Pollutant
Hexachloro- 1 ,3 -butadiene
Hexavalent Chromium
Manganese (PM10)
Manganese (TSP)
Naphthalene
Nickel (TSP)
£>-Dichlorobenzene
Tetrachloroethylene
Xylenes
#of
Measured
Detections
6
24
31
31
31
31
31
23
31
Maximum
Temperature
0.32
0.22
0.40
0.24
0.27
0.16
0.23
0.08
0.20
Temperature
0.05
0.21
0.36
0.24
0.13
0.18
0.16
-0.03
0.12
Dew Point
Temperature
-0.18
0.03
0.17
0.09
0.08
0.21
0.19
-0.08
0.16
Wet Bulb
Temperature
-0.07
0.12
0.25
0.15
0.09
0.20
0.19
-0.05
0.15
Relative
Humidity
-0.27
-0.29
-0.29
-0.27
-0.04
0.18
0.16
-0.06
0.15
Sea Level
Pressure
0.71
0.04
0.18
0.19
0.15
-0.18
0.21
0.13
0.29
Scalar
Wind
Speed
-0.60
-0.15
-0.23
0.05
-0.65
0.02
-0.55
-0.54
-0.65
Providence, Alabama - PVAL
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
Carbon Tetrachloride
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese (TSP)
Naphthalene
£>-Dichlorobenzene
31
10
31
31
31
31
5
31
31
27
0.17
0.21
0.31
-0.10
0.17
0.37
0.43
0.44
0.02
0.34
0.16
0.12
0.23
-0.13
0.16
0.34
0.40
0.39
0.03
0.45
0.17
0.21
0.18
-0.05
0.12
0.33
0.36
0.22
0.05
0.55
0.17
0.16
0.21
-0.08
0.14
0.34
0.39
0.28
0.03
0.53
0.12
0.46
0.00
0.17
0.00
0.15
-0.13
-0.33
0.02
0.59
-0.33
-0.01
0.21
0.06
-0.32
-0.36
0.06
-0.11
0.22
-0.22
-0.06
-0.56
-0.59
-0.23
-0.04
-0.16
0.45
-0.37
-0.11
-0.10
Sloss Industries, Birmingham, Alabama - SIAL
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
Benzo (a) pyrene
Beryllium (TSP)
Carbon Tetrachloride
28
31
19
31
31
27
31
31
-0.30
0.51
0.55
-0.28
-0.24
-0.34
0.11
0.20
-0.33
0.40
0.49
-0.27
-0.22
-0.30
0.08
0.16
-0.24
0.14
0.53
-0.14
-0.16
-0.27
0.07
0.01
-0.28
0.24
0.54
-0.20
-0.18
-0.28
0.07
0.08
0.11
-0.44
0.24
0.21
0.06
-0.04
0.05
-0.28
-0.11
0.03
-0.23
-0.13
-0.29
-0.33
-0.01
-0.27
-0.25
-0.47
-0.49
0.07
-0.01
0.35
-0.18
0.12
to
oo
-------
Table 4-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Alabama
Monitoring Sites (Continued)
Pollutant
Dibenz (a,h) anthracene
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Hexavalent Chromium
Manganese (TSP)
Naphthalene
Nickel (TSP)
£>-Dichlorobenzene
Tetrachloroethylene
#of
Measured
Detections
21
31
6
23
31
31
31
31
22
Maximum
Temperature
-0.41
0.68
-0.69
0.07
0.12
-0.13
0.05
0.28
0.02
Temperature
-0.35
0.67
-0.63
0.09
0.09
-0.17
0.02
0.17
-0.10
Dew Point
Temperature
-0.24
0.46
-0.38
-0.13
0.06
-0.19
0.10
0.18
-0.02
Wet Bulb
Temperature
-0.28
0.54
-0.52
-0.04
0.07
-0.19
0.07
0.18
-0.05
Relative
Humidity
0.19
-0.22
0.21
-0.47
0.00
-0.07
0.22
0.11
0.20
Sea Level
Pressure
-0.28
-0.11
-0.25
0.28
0.00
-0.08
-0.09
0.13
0.31
Scalar
Wind
Speed
0.38
-0.23
0.56
-0.12
-0.17
-0.32
-0.08
-0.50
-0.58
to
VO
-------
• Most of the pollutants also exhibited a positive correlation with sea level pressure,
indicating that concentrations tend to increase as pressure increases.
• Nearly all of the pollutants of interest exhibited a negative correlation with wind
speed, many of which were strong, indicating that concentrations increase as wind
speeds decrease.
• Although some of the correlations for hexachloro-l,3-butadiene were strong, the low
detection rate of this pollutant may skew the correlations.
The following observations are gathered for NBAL from Table 4-5:
• Correlations between the pollutants of interest for NBAL and the selected
meteorological parameters were similar to those calculated for ETAL.
• Most of the correlations between the temperature and moisture variables and the
pollutants of interest were positive, indicating that concentrations tend to increase as
temperature and humidity increase.
• Formaldehyde exhibited even stronger correlations with the temperature and moisture
variables for NBAL.
• Most of the pollutants also exhibited a positive correlation with sea level pressure,
indicating that concentrations tend to increase as pressure increases.
• Nearly all of the pollutants of interest exhibited a strong negative correlation with
wind speed, indicating that concentrations increase as wind speeds decrease.
The following observations are gathered for PVAL from Table 4-5:
• Correlations tended to be weaker for PVAL, although the temperature and moisture
trend of mostly positive correlations continues, indicating that concentrations tend to
increase as temperature and humidity increase.
• Most of the negative correlations were calculated for scalar wind speed, indicating
that concentrations increase as wind speeds decrease.
The following observations are gathered for SIAL from Table 4-5:
• The correlations for SIAL were somewhat different from the other sites.
• More pollutants exhibited negative correlations with the temperature and moisture
variables. However, pollutants such as formaldehyde, acetaldehyde, and acrolein still
exhibited strong positive correlations with these parameters.
4-30
-------
• Most of the correlations with sea level pressure were negative, indicating that
concentrations tend to increase as pressure decreases.
• Like all of the other Alabama sites, correlations with wind speed were mostly
negative, indicating that concentrations increase as wind speeds decrease.
4.4.2 Composite Back Trajectory Analysis
Figures 4-12 through 4-15 are composite back trajectory maps for the Alabama
monitoring sites for the days on which sampling occurred. Each line represents the 24-hour
trajectory along which a parcel of air traveled toward the monitoring site on a sampling day and
each concentric circle represents 100 miles.
The following observations can be made from Figures 4-12 through 4-15.
• The back trajectory maps look very similar to each other.
• Back trajectories originated from a variety of directions at the Alabama sites.
• The 24-hour airshed domain is somewhat large for these sites, with trajectories
originating as far away as southern Iowa, or greater than 600 miles away.
• Nearly 90 percent of the trajectories originated within 400 miles of the Alabama sites.
4.4.3 Wind Rose Analysis
Hourly wind data from the Birmingham International Airport and Tuscaloosa Municipal
Airport stations were uploaded into a wind rose software program, WRPLOT (Lakes, 2006).
WRPLOT produces a graphical wind rose from the wind data. A wind rose shows the frequency
of wind directions about a 16-point compass, and uses different shading to represent wind
speeds. Figures 4-16 through 4-19 are the wind roses for the Alabama monitoring sites on days
that sampling occurred.
As shown in Figures 4-16, 4-17, and 4-19 (for ETAL, NBAL, and SIAL):
• The wind roses for the three sites within the Birmingham city limits resembled each
other.
• Hourly winds were predominantly out of the north, south, and south-southeast on
days that samples were collected.
4-31
-------
Figure 4-12. Composite Back Trajectory Map for ETAL
J^.
I
to
-------
Figure 4-13. Composite Back Trajectory Map for NBAL
-------
Figure 4-14. Composite Back Trajectory Map for PVAL
-------
Figure 4-15. Composite Back Trajectory Map for SIAL
-------
Figure 4-16. Wind Rose for ETAL Sampling Days
4%
10%
8%,
&%-.
SOUTH,-'
EAST
WIND SPEED
(Knots 3
| | s= 22
II 17 - 21
^| 11 - 17
I I ^l- 7
^| 2- 4
Calms: 27.92%
-------
Figure 4-17. Wind Rose for NBAL Sampling Days
10%
8%,
6%..
SOUTH,-'
EAST
WIND SPEED
(Knots 3
| | >= 22
^| 17 • 21
I I 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 23.06%
-------
Figure 4-18. Wind Rose for PVAL Sampling Days
J^.
I
oo
15%
12%
9%..
6%.
SOUTH,-'
EAST
WIND SPEED
(Knots 3
| | >= 22
^| 17 • 21
I I 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 34.75%
-------
Figure 4-19. Wind Rose for SIAL Sampling Days
J^.
I
VO
10%
8%,
6%..
SOUTH,-"
I EAST
WIND SPEED
(Knots 3
| | >= 22
^| 17 • 21
I I 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 23.29%
-------
• Calm winds (<2 knots) were recorded for nearly thirty percent of the hourly
measurements at these sites.
• For wind speeds greater than 2 knots, most of the observations ranged from 7 to 11
knots.
As shown in Figure 4-18 (for PVAL)
• Southerly (12 percent), west-northwesterly (8 percent), and westerly (7 percent),
winds were predominant near PVAL on days that samples were collected.
• Nearly 35 percent of hourly wind speed observations were calm, or less than 2 knots.
• Wind speeds in the 7 to 11 knot range were the most often recorded.
4.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic volume comparisons; and BTEX analysis.
A mobile tracer analysis could not be performed as these sites did not sample for SNMOC.
4.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Jefferson County, Alabama were
obtained from the Alabama Department of Revenue and the U.S. Census Bureau, and are
summarized in Table 4-6. Table 4-6 also includes a vehicle registration to county population
ratio (vehicles per person). In addition, the population within 10 miles of each site is presented.
An estimation of 10-mile vehicle registration was computed using the 10-mile population
surrounding the monitor and the vehicle registration ratio. Finally, Table 4-6 contains the
average daily traffic information, which represents the average number of vehicles passing the
monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 4-6 include:
• PVAL has a significantly lower population residing within 10 miles of it than the
other sites, and therefore a significantly lower estimated 10 mile vehicle ownership.
• Traffic data for three Birmingham sites was obtained from the Alabama Department
of Transportation, but no traffic data was available for PVAL.
4-40
-------
Table 4-6. Motor Vehicle Information for the Alabama Monitoring Sites
Site
ETAL
NBAL
PVAL
SIAL
2006 Estimated
County
Population
656,700
656,700
656,700
656,700
Number of
Vehicles
Registered
614,075
614,075
614,075
614,075
Vehicles per Person
(Registration:
Population)
0.94
0.94
0.94
0.94
Population
Within 10 Miles
394,178
389,196
28,587
389,196
Estimated 10
mile Vehicle
Ownership
368,593
363,934
26,731
363,934
Traffic Data
(Daily Average)
30,000
2,000
NA
2,700
NA = Not available.
-------
• The ETAL site experiences a significantly higher daily traffic volume than NBAL
and SIAL. According to Figure 4-1, ETAL resides next to a major interstate.
• Compared to other UATMP locations, Jefferson County's population and vehicle
registration are in the middle of the range.
4.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information of this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compared them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• Of the four Alabama sites, the NBAL monitoring site's ratios most resemble those of
the roadside study, although its ratios were lower than those of the roadside study's.
This suggests that mobile source emissions are influencing concentrations at this site.
• For ETAL, the benzene-ethylbenzene and xylenes-ethylbenzene ratios were very
similar to each other, while the toluene-ethylbenzene ratio was the highest of the
three.
• For PVAL, the benzene-ethylbenzene and toluene ethylbenzene ratios were
significantly higher than those of the roadside study. In addition, the benzene-
ethylbenzene ratio was much higher than the xylenes-ethylbenzene ratio.
• For SIAL, the benzene-ethylbenzene ratio was the highest of the three ratios, which
was different from the roadside study, where the toluene-ethylbenzene ratio was the
highest.
• These observations suggests that sources other than mobile sources are influencing
concentrations at these sites.
4.6 Trends Analysis
A trends analysis could not be performed as these sites have not participated in the
UATMP for three consecutive years.
4-42
-------
4.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Alabama sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 4-7. NATA data
is presented for the census tract where the monitoring site is located. Additionally, the pollutants
of interest are bolded.
The following observations based on annual averages for the Birmingham sites can be
seen in Table 4-7:
• The pollutants with the top 3 annual averages by mass concentration for ETAL,
NBAL, and SIAL were xylenes, formaldehyde, and benzene, although not necessarily
in that order. Xylenes consistently had the highest annual average among these three
sites.
• The pollutants with the highest cancer risks were not necessarily these pollutants.
• Theoretical cancer risk for benzene was the highest for all three sites, ranging from
22.65 in-a-million (for NBAL) to 48.15 in-a-million (for ETAL).
• Cancer risks resulting from hexachloro-1,3-butadiene were also high, ranging from
10.90 in-a-million (for NBAL) to 12.04 (for SIAL).
• Other pollutants with cancer risks greater than 10 in-a-million included carbon
tetrachloride (for ETAL and NBAL), arsenic (for SIAL), and naphthalene (for SIAL).
• Acrolein and manganese exhibited noncancer HQs greater than 1 for all three sites.
However, the acrolein HQ for each site was significantly higher than the manganese
HQ.
• All other noncancer risks were less than 1.0.
The following observations based on annual averages for PVAL can be seen in Table 4-7:
• Formaldehyde, acetaldehyde, and hexachloro-1,3-butadiene exhibited the highest
annual averages.
• Like the other three Birmingham sites, hexachloro-1,3-butadiene had the highest
theoretical cancer risk (15.61 in-a-million).
4-43
-------
Table 4-7. Chronic Risk Summary for the Monitoring Sites in Alabama
Pollutant
Cancer
URE
(Hg/rn3)
Noncancer
RfC
(Mg/m3)
1999 NATA
Modeled
Concentration
(Ug/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
2005-2006 UATMP
Annual Average
(Ug/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
East Thomas, Birmingham, Alabama (ETAL) - Census Tract ID 01073001200
Acet aldehyde
Acrolein
Acrylonitrile
Arsenic*
Benzene
Benzo (a) pyrene
1,3-Butadiene
Cadmium*
Carbon Tetrachloride
p-Dichlorobenzene
Ethyl Acrylate
Formaldehyde
Hexachloro-l,3-butadiene
Hexavalent Chromium
Manganese*
Naphthalene
Nickel*
Tetrachloroethylene
Xylenes
0.0000022
NR
0.000068
0.0043
0.0000078
0.001
0.00003
0.0018
0.000015
0.000011
0.000014
5.5E-09
0.000022
0.012
NR
0.000034
0.00016
0.0000059
NR
0.009
0.00002
0.002
0.00003
0.03
NR
0.002
0.00002
0.04
0.8
NR
0.0098
0.09
0.0001
0.00005
0.003
0.000065
0.27
0.1
2.04
0.14
0.01
0.03
2.06
<0.01
0.16
0.18
0.22
0.03
0.01
1.81
0.01
O.01
5.94
0.09
0.42
0.17
3.32
4.48
NR
0.13
0.14
16.03
0.07
4.81
0.32
3.24
0.37
0.01
0.01
0.03
0.91
NR
2.98
0.07
1.03
NR
0.23
6.81
0.01
O.01
0.07
NR
0.08
0.01
0.01
0.01
NR
0.18
0.01
O.01
0.12
0.03
0.01
0.01
0.03
1.99 ±0.27
0.57 ±0.23
0.06 ±0.01
<0.01±<0.01
2.90 ±0.65
<0.01±<0.01
0.25 ±0.06
0.01 ±0.01
0.68 ±0.04
0.28 ±0.06
0.07 ± 0.02
4.90 ±0.76
0.50 ±0.23
<0.01±<0.01
0.05 ±0.01
0.27 ±0.09
O.01±O.01
0.37±0.11
7.57 ±1.89
4.37
NR
4.24
6.69
22.65
0.41
7.41
0.82
10.27
3.05
0.99
0.03
11.1
0.55
NR
9.03
0.33
2.21
NR
0.22
28.47
0.03
0.05
0.1
NR
0.12
0.02
0.02
0.01
NR
0.5
0.01
O.01
1.09
0.09
0.03
0.01
0.08
North Birmingham, Alabama (NBAL) - Census Tract ID 01073000800
Acet aldehyde
Acrolein
Acrylonitrile
Arsenic*
Arsenic (PM10)
Benzene
0.0000022
NR
0.000068
0.0043
0.0043
0.0000078
0.009
0.00002
0.002
0.00003
0.00003
0.03
2.22
0.15
0.01
0.03
0.03
2.53
4.89
NR
0.16
0.11
0.11
19.77
0.25
7.71
0.01
O.01
0.01
0.08
1.65 ±0.25
0.65 ±0.20
0.06 ±0.01
<0.01±<0.01
0.01 ±0.01
3.17±1.17
3.62
NR
4.42
8.94
9.03
24.72
0.18
32.62
0.03
0.07
0.07
0.11
-------
Table 4-7. Chronic Risk Summary for the Monitoring Sites in Alabama (Continued)
Pollutant
Benzo (a) anthracene
Benzo (a) pyrene
Benzo (b) fluoranthene
Benzo (k) fluoranthene
1,3-Butadiene
Cadmium*
Cadmium (PM10)
Carbon Tetrachloride
Dibenz (a,h) anthracene
p-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro-l,3-butadiene
Hexavalent Chromium
Indeno( 1,2,3 -cd)pyrene
Manganese (PM10)
Manganese*
Naphthalene
Nickel*
Nickel (PM10)
Tetrachloroethylene
Trichloroethylene
Xylenes
Cancer
URE
(Hg/rn3)
0.0001
0.001
0.0001
0.0001
0.00003
0.0018
0.0018
0.000015
0.001
0.000011
0.000026
5.5E-09
0.000022
0.012
0.0001
0.000034
0.00016
0.00016
0.0000059
0.000002
Noncancer
RfC
Oig/m3)
NR
NR
NR
NR
0.002
0.00002
0.00002
0.04
0.8
2.4
0.0098
0.09
0.0001
0.00005
0.00005
0.003
0.000065
0.000065
0.27
0.6
0.1
1999 NATA
Modeled
Concentration
(Ug/m3)
0.01
O.01
O.01
0.01
0.21
0.9
0.9
0.21
0.01
0.03
0.03
1.95
O.01
0.01
O.01
10.74
10.74
0.11
0.75
0.75
0.18
0.12
6.31
Cancer
Risk (in-a-
million)
0.05
0.08
0.05
0.05
6.17
1.61
1.61
3.19
0.08
0.38
0.83
0.01
0.03
1.08
0.05
NA
NA
3.85
0.12
0.12
1.04
0.25
NA
Noncancer
Risk (HQ)
NR
NR
NR
NR
0.1
0.04
0.04
0.01
NA
O.01
0.01
0.2
O.01
0.01
NA
0.21
0.21
0.04
0.01
0.01
0.01
0.01
0.06
2005-2006 UATMP
Annual Average
(Ug/m3)
0.01 ±0.01
O.OliO.Ol
O.OliO.Ol
0.01 ±0.01
0.15 ±0.05
0.01 ±0.01
O.01±O.01
0.67 ±0.05
0.01 ±0.01
0.32 ±0.06
0.05 ±0.01
4.17 ±0.89
0.50 ±0.23
0.01 ±0.01
O.01±O.01
0.04 ±0.01
0.07 ± 0.02
0.29 ±0.09
0.01 ±0.01
O.01±O.01
0.24 ±0.08
0.11 ±0.05
9.66 ±2.88
Cancer
Risk (in-a-
million)
0.32
1.77
0.23
0.21
4.39
1.48
1.27
10.02
0.39
3.51
1.31
0.02
10.9
0.6
0.14
NA
NA
9.74
0.29
0.22
1.44
0.22
NA
Noncancer
Risk (HQ)
NR
NR
NR
NR
0.07
0.04
0.04
0.02
NA
O.01
0.01
0.43
0.01
0.01
NA
0.71
1.39
0.1
0.03
0.02
0.01
0.01
0.1
-------
Table 4-7. Chronic Risk Summary for the Monitoring Sites in Alabama (Continued)
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
2005-2006 UATMP
Annual Average
(Hg/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Providence, Alabama (PVAL) - Census Tract ID 01073014102
Acet aldehyde
Acrolein
Acrylonitrile
Arsenic*
Benzene
1,3 -Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
Formaldehyde
Hexachloro-l,3-butadiene
Manganese*
Naphthalene
0.0000022
NR
0.000068
0.0043
0.0000078
0.00003
0.000015
0.000011
5.5E-09
0.000022
NR
0.000034
0.009
0.00002
0.002
0.00003
0.03
0.002
0.04
0.8
0.0098
0.09
0.00005
0.003
1.27
0.07
<0.01
0.04
0.96
0.07
0.21
0.01
1.31
0.01
2.74
0.03
2.79
NR
0.04
0.18
7.47
2.18
3.17
0.12
0.01
0.03
NR
1.05
0.14
3.40
O.01
O.01
0.03
0.04
0.01
O.01
0.13
0.01
0.05
0.01
1.49 ±0.82
0.28 ±0.18
0.06 ±0.01
O.01±O.01
0.57 ±0.10
0.03 ±0.02
0.65 ±0.05
0.22 ±0.08
4. 14 ±2.06
0.71 ±0.27
0.01 ±O.01
0.02 ±0.01
3.28
NR
4.00
3.46
4.47
0.91
9.82
2.42
0.02
15.61
NR
0.58
0.17
13.77
0.03
0.03
0.02
0.02
0.02
O.01
0.42
0.01
0.13
0.01
Sloss Industries, Birmingham, Alabama (SIAL) - Census Tract ID 01073005500
Acet aldehyde
Acrolein
Acrylonitrile
Arsenic*
Benzene
Benzo (a) anthracene
Benzo (a) pyrene
Benzo (b) fluoranthene
Benzo (k) fluoranthene
Beryllium*
1,3-Butadiene
Cadmium*
0.0000022
NR
0.000068
0.0043
0.0000078
0.0001
0.001
0.0001
0.0001
0.0024
0.00003
0.0018
0.009
0.00002
0.002
0.00003
0.03
NR
NR
NR
NR
0.00002
0.002
0.00002
2.05
0.14
O.01
0.03
2.49
O.01
0.01
O.01
0.01
0.01
0.17
0.42
4.52
NA
0.23
0.13
19.41
0.05
0.08
0.05
0.05
0.01
5.01
0.75
0.23
6.90
O.01
0.01
0.08
NR
NR
NR
NR
0.01
0.08
0.02
1.55±0.19
0.73 ±0.32
0.07 ± 0.02
0.01 ±0.01
6. 17 ±2.07
O.01±O.01
0.01 ±0.01
O.01±O.01
0.01 ±0.01
0.01 ±0.01
0.21 ±0.05
0.01 ±0.01
3.41
NA
4.61
24.79
48.15
0.31
1.95
0.31
0.25
0.73
6.36
0.66
0.17
36.57
0.03
0.19
0.21
NR
NR
NR
NR
0.02
0.11
0.02
-------
Table 4-7. Chronic Risk Summary for the Monitoring Sites in Alabama (Continued)
Pollutant
Carbon Tetrachloride
Chloromethylbenzene
Dibenz (a,h) anthracene
p-Dichlorobenzene
Formaldehyde
Hexachloro-l,3-butadiene
Hexavalent Chromium
Indeno( 1,2,3 -cd)pyrene
Manganese*
Naphthalene
Nickel*
Tetrachloroethylene
Xylenes
Cancer
URE
(Hg/rn3)
0.000015
0.000049
0.001
0.000011
5.5E-09
0.000022
0.012
0.0001
NR
0.000034
0.00016
0.0000059
NR
Noncancer
RfC
Oig/m3)
0.04
NR
NR
0.8
0.0098
0.09
0.0001
NR
0.00005
0.003
0.000065
0.27
0.1
1999 NATA
Modeled
Concentration
(Ug/m3)
0.21
<0.01
<0.01
0.03
1.84
0.01
O.01
O.01
10.65
0.09
0.74
0.17
5.80
Cancer
Risk (in-a-
million)
3.15
O.01
0.08
0.31
0.01
0.03
1.00
0.05
NR
3.12
0.12
1.00
NR
Noncancer
Risk (HQ)
0.01
NR
NR
0.01
0.19
0.01
O.01
NR
0.21
0.03
0.01
0.01
0.06
2005-2006 UATMP
Annual Average
(Ug/m3)
0.65 ±0.04
0.05 ±0.01
O.01±O.01
0.40 ±0.11
3.70 ±0.71
0.55 ±0.24
O.01±O.01
O.01±O.01
0.14 ±0.05
0.50 ±0.12
0.01 ±0.01
0.24 ±0.07
6.24 ±1.40
Cancer
Risk (in-a-
million)
9.73
2.34
0.44
4.39
0.02
12.04
0.63
0.19
NR
16.85
0.34
1.43
NR
Noncancer
Risk (HQ)
0.02
NR
NR
0.01
0.38
0.01
O.01
NR
2.79
0.17
0.03
0.01
0.06
*Metals sampled were sampled with TSP filters, except where indicated otherwise.
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
NA = Not available due to the short sampling duration.
-------
• The noncancer HQ from acrolein was also greater than 1.0 (13.77), but was about half
as high as those calculated for the other sites.
• No other pollutant had a noncancer HQ greater than 1.0 for PVAL.
In addition to the annual averages and risks based on 2005-2006 monitoring data, data
from EPA's 1999 NATA were retrieved and are also presented in Table 4-7. The census tract for
each Alabama site is presented in Table 4-7. Populations from the 2000 Census for each census
tracts ranged from 2,689 (or 0.4 percent of the 2000 county total) for SIAL to 5,387 (or
0.8 percent of the 2000 county total) for NBAL.
The following observations can be garnered for the three Birmingham sites (ETAL,
NBAL, and SIAL) from Table 4-7:
• Manganese, xylenes, benzene, and acetaldehyde (in that order) exhibited the highest
NATA-modeled concentrations.
• While actual measured concentrations of manganese were much lower than the
modeled concentrations, the annual averages of xylenes and benzene did have some
of the highest annual averages at these sties.
• Manganese and xylenes do not have cancer risk factors.
• Benzene exhibited the highest modeled cancer risks at all three sites, ranging from
16.03 in-a-million (at ETAL) to 19.77 in-a-million (at NBAL). These risk were
similar to those calculated for ETAL and NBAL, but the calculated risk for benzene
for SIAL (48.15 in-a-million) was more than twice the modeled cancer risk (19.41 in-
a-million).
• Acrolein was the only pollutant with a noncancer HQ greater than 1.0 at all three
sites, although the modeled noncancer risks were much lower than the calculated
noncancer risks for each site.
The following observations can be garnered for PVAL from Table 4-7:
• Manganese, formaldehyde, and acetaldehyde had the highest modeled concentrations.
• The highest modeled cancer risks were attributable to benzene, carbon tetrachloride,
and acetaldehyde.
4-48
-------
• Acrolein was the only pollutant with a noncancer HQ greater than 1.0, although the
modeled noncancer risk (3.40) was much lower than the calculated noncancer risk
(13.77).
4.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 4-8 and 4-9 present a risk-
based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 4-8 presents the 10 pollutants with the highest emissions from the 2002 NEI,
the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with the
highest cancer risk (in-a-million) as calculated from the annual average. Table 4-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average concentration is limited to those pollutants for
which each respective site sampled. In addition, the highest cancer and noncancer risks based on
annual averages are limited to those pollutants failing at least one screen.
The following observations can be made from Table 4-8:
• Benzene, formaldehyde, and acetaldehyde were the top three emitted pollutants with
cancer risk factors in Jefferson County, while benzene, lead, and 1,3-butadiene had
the top three toxicity-weighted emissions.
• Benzene also had the highest cancer risk based on the annual average concentration
forNBAL, ETAL, and SIAL, ranging from 22.65 in-a-million (for ETAL) to 48.15
in-a-million (for SIAL).
• Benzene's cancer risk for PVAL ranked third, and was considerably lower than the
Birmingham sites (4.47 in-a-million).
• While hexachloro-1,3-butadiene had the second highest cancer risk based on the
annual average for ETAL and NBAL, this pollutant's cancer risk ranked first for
PVAL and fifth for SIAL, yet the cancer risks were all relatively similar.
4-49
-------
Table 4-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Alabama
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(Jefferson County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(Jefferson County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer
Risk
(in-a-
million)
East Thomas, Birmingham, Alabama - ETAL
Benzene
Formaldehyde
Acetaldehyde
Tetrachloroethylene
1 ,3 -Dichloropropene
1,3 -Butadiene
Dichloromethane
Naphthalene
/>-Dichlorobenzene
Poly cyclic Organic Matter as 15 -PAH
1,914.42
1,040.74
373.93
280.30
238.49
237.53
162.04
138.65
123.56
14.67
Benzene
Lead
1,3 -Butadiene
Naphthalene
Arsenic
Tetrachloroethylene
£>-Dichlorobenzene
1 ,3 -Dichloropropene
Hexavalent Chromium
Acetaldehyde
1.49E-02
1.13E-02
7.13E-03
4.71E-03
1.69E-03
1.65E-03
1.36E-03
9.54E-04
8.61E-04
8.23E-04
Benzene
Hexachloro- 1 , 3 -butadiene
Carbon Tetrachloride
Naphthalene
1,3 -Butadiene
Arsenic
Acetaldehyde
Acrylonitrile
/>-Dichlorobenzene
Tetrachloroethylene
22.65
11.10
10.27
9.03
7.41
6.69
4.37
4.24
3.05
2.21
North Birmingham, Alabama - NBAL
Benzene
Formaldehyde
Acetaldehyde
Tetrachloroethylene
1 ,3 -Dichloropropene
1,3 -Butadiene
Dichloromethane
Naphthalene
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15 -PAH
1,914.42
1,040.74
373.93
280.30
238.49
237.53
162.04
138.65
123.56
14.67
Benzene
Lead
1,3 -Butadiene
Naphthalene
Arsenic
Tetrachloroethylene
/>-Dichlorobenzene
1 ,3 -Dichloropropene
Hexavalent Chromium
Acetaldehyde
1.49E-02
1.13E-02
7.13E-03
4.71E-03
1.69E-03
1.65E-03
1.36E-03
9.54E-04
8.61E-04
8.23E-04
Benzene
Hexachloro- 1 , 3 -butadiene
Carbon Tetrachloride
Naphthalene
Arsenic (PM10)
Arsenic (TSP)
Acrylonitrile
1,3 -Butadiene
Acetaldehyde
/>-Dichlorobenzene
24.72
10.90
10.02
9.74
9.03
8.94
4.42
4.39
3.62
3.51
-^
o
-------
Table 4-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Alabama (Continued)
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(Jefferson County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(Jefferson County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer
Risk
(in-a-
million)
Providence, Alabama - PVAL
Benzene
Formaldehyde
Acetaldehyde
Tetrachloroethylene
1 ,3 -Dichloropropene
1,3 -Butadiene
Dichloromethane
Naphthalene
/>-Dichlorobenzene
Poly cyclic Organic Matter as 15-PAH
1,914.42
1,040.74
373.93
280.30
238.49
237.53
162.04
138.65
123.56
14.67
Benzene
Lead
1,3 -Butadiene
Naphthalene
Arsenic
Tetrachloroethylene
£>-Dichlorobenzene
1 ,3 -Dichloropropene
Hexavalent Chromium
Acetaldehyde
1.49E-02
1.13E-02
7.13E-03
4.71E-03
1.69E-03
1.65E-03
1.36E-03
9.54E-04
8.61E-04
8.23E-04
Hexachloro- 1 , 3 -butadiene
Carbon Tetrachloride
Benzene
Acrylonitrile
Arsenic
Acetaldehyde
£>-Dichlorobenzene
1,3 -Butadiene
Naphthalene
Formaldehyde
15.61
9.82
4.47
4.00
3.46
3.28
2.42
0.91
0.58
0.02
Sloss Industries, Birmingham, Alabama - SIAL
Benzene
Formaldehyde
Acetaldehyde
Tetrachloroethylene
1 ,3 -Dichloropropene
1,3 -Butadiene
Dichloromethane
Naphthalene
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15-PAH
1,914.42
1,040.74
373.93
280.30
238.49
237.53
162.04
138.65
123.56
14.67
Benzene
Lead
1,3 -Butadiene
Naphthalene
Arsenic
Tetrachloroethylene
/>-Dichlorobenzene
1 ,3 -Dichloropropene
Hexavalent Chromium
Acetaldehyde
1.49E-02
1.13E-02
7.13E-03
4.71E-03
1.69E-03
1.65E-03
1.36E-03
9.54E-04
8.61E-04
8.23E-04
Benzene
Arsenic
Naphthalene
Hexachloro- 1 ,3 -butadiene
Carbon Tetrachloride
1,3 -Butadiene
Acrylonitrile
£>-Dichlorobenzene
Acetaldehyde
Chloromethylbenzene
48.15
24.79
16.85
12.04
9.73
6.36
4.61
4.39
3.41
2.34
-------
Table 4-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Alabama
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(Jefferson County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(Jefferson County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk
(HQ)
East Thomas, Birmingham, Alabama - ETAL
Toluene
Xylenes
Benzene
Methyl Tert-Butyl Ether
Methanol
Hexane
Formaldehyde
Ethylbenzene
Methyl Ethyl Ketone
1,1,1 -Trichloroethane
5,862.72
4,195.84
1,914.42
1,700.77
1,263.87
1,100.16
1,040.74
925.98
781.84
634.12
Acrolein
1,3 -Butadiene
Formaldehyde
Bromomethane
Benzene
Naphthalene
Xylenes
Acetaldehyde
Cyanide
Cadmium
2,930,122.29
118,762.60
106,198.46
66,526.05
63,814.03
46,217.08
41,958.37
41,547.57
38,836.22
21,408.23
Acrolein
Manganese
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Benzene
Naphthalene
Xylenes
Arsenic
Nickel
28.47
1.09
0.50
0.22
0.12
0.10
0.09
0.08
0.05
0.03
North Birmingham, Alabama - NBAL
Toluene
Xylenes
Benzene
Methyl Tert-Butyl Ether
Methanol
Hexane
Formaldehyde
Ethylbenzene
Methyl Ethyl Ketone
1,1,1 -Trichloroethane
5,862.72
4,195.84
1,914.42
1,700.77
1,263.87
1,100.16
1,040.74
925.98
781.84
634.12
Acrolein
1,3 -Butadiene
Formaldehyde
Bromomethane
Benzene
Naphthalene
Xylenes
Acetaldehyde
Cyanide
Cadmium
2,930,122.29
118,762.60
106,198.46
66,526.05
63,814.03
46,217.08
41,958.37
41,547.57
38,836.22
21,408.23
Acrolein
Manganese (TSP)
Manganese (PM10)
Formaldehyde
Acetaldehyde
Benzene
Xylenes
Naphthalene
1,3 -Butadiene
Arsenic (PM10)
32.62
1.39
0.71
0.43
0.18
0.11
0.10
0.10
0.07
0.07
-^
to
-------
Table 4-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risk for Pollutants with Noncancer RfCs for the
Monitoring Sites in Alabama
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(Jefferson County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity- Weighted Emissions
(Jefferson County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk
(HQ)
Providence, Alabama - PVAL
Toluene
Xylenes
Benzene
Methyl Tert-Butyl Ether
Methanol
Hexane
Formaldehyde
Ethylbenzene
Methyl Ethyl Ketone
1,1,1 -Trichloroethane
5,862.72
4,195.84
1,914.42
1,700.77
1,263.87
1,100.16
1,040.74
925.98
781.84
634.12
Acrolein
1,3 -Butadiene
Formaldehyde
Bromomethane
Benzene
Naphthalene
Xylenes
Acetaldehyde
Cyanide
Cadmium
2,930,122.29
118,762.60
106,198.46
66,526.05
63,814.03
46,217.08
41,958.37
41,547.57
38,836.22
21,408.23
Acrolein
Formaldehyde
Acetaldehyde
Manganese
Acrylonitrile
Arsenic
Benzene
Carbon Tetrachloride
1,3 -Butadiene
Hexachloro- 1 ,3 -butadiene
13.77
0.42
0.17
0.13
0.03
0.03
0.02
0.02
0.02
0.01
Sloss Industries, Birmingham, Alabama - SIAL
Toluene
Xylenes
Benzene
Methyl Tert-Butyl Ether
Methanol
Hexane
Formaldehyde
Ethylbenzene
Methyl Ethyl Ketone
1,1,1 -Trichloroethane
5,862.72
4,195.84
1,914.42
1,700.77
1,263.87
1,100.16
1,040.74
925.98
781.84
634.12
Acrolein
1,3 -Butadiene
Formaldehyde
Bromomethane
Benzene
Naphthalene
Xylenes
Acetaldehyde
Cyanide
Cadmium
2,930,122.29
118,762.60
106,198.46
66,526.05
63,814.03
46,217.08
41,958.37
41,547.57
38,836.22
21,408.23
Acrolein
Manganese
Formaldehyde
Benzene
Arsenic
Acetaldehyde
Naphthalene
1,3 -Butadiene
Xylenes
Acrylonitrile
36.57
2.79
0.38
0.21
0.19
0.17
0.17
0.11
0.06
0.03
-------
• While arsenic had one of the 10 highest cancer risks for all of the sites, the risk for
SIAL was significantly higher than at the remaining sites.
• Although naphthalene also had one of the 10 highest cancer risks for all of the sites,
the risk for PVAL was significantly lower than for the remaining sites.
The following observations can be made from Table 4-9:
• Toluene, xylenes, and benzene were the top three emitted pollutants with noncancer
risk factors in Jefferson County, while acrolein, 1,3-butadiene, and formaldehyde had
the top three toxicity-weighted emissions.
• Acrolein also had the highest noncancer risk based on the annual average
concentration for all four Alabama sites, ranging from 13.77 for PVAL to 36.57 for
SIAL.
• Although acrolein was the only pollutant with a noncancer risk greater than 1.0 for
most UATMP sites, manganese had noncancer HQs greater than 1.0 for the three
Birmingham sites, ranging from 1.09 for ETAL to 2.79 for SIAL. Manganese,
however, did not have one of 10 highest toxicity-weighted emissions, and neither
acrolein nor manganese was one of the most emitted pollutants in Jefferson County.
Alabama Pollutant Summary
• The pollutants of interest common to each Alabama site were acetaldehyde, arsenic
(TSP), acrolein, benzene, carbon tetrachloride, p-dichlorobenzene, formaldehyde,
hexachloro-1,3-butadiene, manganese (TSP), and naphthalene.
• Among each sites pollutants of interest, total xylenes had the highest daily average for
ETAL andNBAL, while formaldehyde had the highest daily average for PVAL, and
benzene had the highest daily average for SIAL.
• Acrolein exceeded both of the short-term risk factors at each Alabama site and benzene
exceeded the A TSDR MRL at SIAL.
4-54
-------
5.0 Site in Arizona
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Phoenix, Arizona (PXSS). Figure 5-1 is a topographical map showing the monitoring site
in its urban location. Figure 5-2 identifies point source emission locations within 10 miles of this
site as reported in the 2002 NEI for point sources. The Phoenix site is surrounded by numerous
point sources, mostly located to the southeast, south, and southwest of the site. A large number
of point sources near PXSS fall into the fuel combustion source category.
The Phoenix area is located in the Salt River Valley, which is part of the Sonora Desert.
The area experiences mild winters and extremely hot and dry summers. Differences between the
daytime maximum temperature and overnight minimum temperature can be as high as
50 degrees. A summer "monsoon" period brings precipitation to the area for part of the summer,
while storms originating off the Pacific Coast bring rain in the winter and early spring. Winds
are generally light. (Ruffner and Bair, 1987 and WRCC, 2006).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the PXSS monitoring site is Sky Harbor International Airport (WBAN 23183). Table 5-1
presents average meteorological conditions of temperature (average maximum and average),
moisture (average dew point temperature, average wet-bulb temperature, and average relative
humidity), pressure (average sea level pressure), and wind information (average scalar wind
speed) for the entire year and on days samples were collected. Also included in Table 5-1 is the
95 percent confidence interval. As shown in Table 5-1, average meteorological conditions on
sampling days were fairly representative of average weather conditions throughout the year.
5.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Arizona
monitoring site. As described in Section 3.1.4, the methodology for evaluating pollutants of
5-1
-------
Figure 5-1. Phoenix, Arizona (PXSS) Monitoring Site
^ffry ,"J-.•.;:'•- *&>
,,v v*i>|8
-------
Figure 5-2. Facilities Located Within 10 Miles of PXSS
Marico^a
County
F ;
F if
" »
s
Note; Due to facility density anti collocation, the to^al facilities
displayed may not represent 38 facilities within the area of interest.
Legend
PXSS UATMP site
10 mile radius
Source Category Group (No. of Facilities)
C Chemicals & Allied Products Facility (3)
Electrical & Electronic Equipment Facility (1)
Fabricated Metal Products Facility (5)
Fuel Combustion Industrial Facility (33)
Industrial Machinery & Equipment Facility (3)
Integrated Iron & Steel Manufacturing Facility (1}
Liquids Distribution Industrial Facility (8)
Lumber & Wood Products Facility (2)
Mineral Products Processing Industrial Facility (3)
Miscellaneous Manufacturing Industries (1)
Miscellaneous Processes Industrial Facility (7)
| County boundary
\ Non-ferrous Metals Processing Industrial Facility (3)
@ Papers Allied Products (1)
Polymers & Resins Production Industrial Facility (1)
Primary Metal Industries Facility (1)
Production of Organic Chemicals Industrial Facility (1)
Rubber & Miscellaneous Plastic Products Facility (1)
Stone. Clay, Glass. & Concrete Products (1)
Surface Coating Processes Industrial Facility (5)
Utility Boilers (3)
Waste Treatment & Disposal Industrial Facility (5)
Wholesale Trade (3)
5-3
-------
Table 5-1. Average Meteorological Conditions near the Monitoring Site in Arizona
Site
PXSS
WBAN
23183
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(op)
86.22
± 1.58
85.37
±3.63
Average
Temperature
(»F)
75.49
±1.59
74.61
±3.70
Average
Dew Point
Temperature
(°F)
36.13
± 1.55
36.63
±3.52
Average
Wet Bulb
Temperature
(°F)
55.33
±1.10
54.59
±2.56
Average
Relative
Humidity
(%)
28.32
±1.33
28.93
±2.90
Average
Sea Level
Pressure
(mb)
1012.09
±0.52
1012.70
±1.24
Average
Scalar Wind
Speed
(kt)
5.79
±0.20
5.84
±0.48
-------
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs are
listed in the EPA guidance as having risk screening values. If the daily concentration value was
greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. PXSS sampled hexavalent chromium and
metals (PMi0). Table 5-2 presents the five pollutants that failed at least one screen at PXSS.
The following observations are shown in Table 5-2:
• A total of 155 measured concentrations (over 50 percent) failed screens.
• The screening process at PXSS resulted in three pollutants of interest: manganese (57
failed screens), arsenic (56), and hexavalent chromium (35).
• More than 90 percent of the measured detections of manganese and arsenic exceeded the
screening values.
Table 5-2. Comparison of Measured Concentrations and EPA Screening Values for the
Arizona Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Phoenix, Arizona - PXSS
Manganese (PM10)
Arsenic (PM10)
Hexavalent Chromium
Nickel (PM10)
Cadmium (PM10)
Total
57
56
35
6
1
155
59
59
58
59
59
294
96.61
94.92
60.34
10.17
1.69
52.72
36.77
36.13
22.58
3.87
0.65
36.77
72.90
95.48
99.35
100.00
5.2 Concentration Averages
Three types of concentration averages were calculated for the following subsections:
daily, seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
a season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
5-5
-------
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects were incorporated into the
average. Annual averages were calculated for monitoring sites where sampling began no later
than February and ended no earlier than November. Daily and seasonal averages are presented
in Table 5-3. Annual averages are presented and discussed in further detail in later sections.
The following observations are shown in Table 5-3:
• Manganese had the highest daily average concentration by mass at PXSS (18.08 ± 2.31
ng/m3).
• The seasonal averages for hexavalent chromium and manganese did not vary
significantly.
• The autumn and winter arsenic averages were slightly higher than the spring and summer
averages.
• Arsenic and manganese were detected in every sample collected at PXSS, and hexavalent
chromium was detected in all but one measurement.
5.3 Non-Chronic Risk Evaluation
Non-chronic risk based on the concentration data for PXSS was evaluated using ATSDR
acute and intermediate MRL and California EPA acute REL factors. Acute risk is defined as
exposures from 1 to 14 days while intermediate risk is defined as exposures from 15 to 364 days.
It is useful to compare preprocessed daily measurements to the short-term MRL and REL
factors, as well as compare seasonal averages to the intermediate MRL. Of the five pollutants
with at least one failed screen, none exceeded either of the acute and intermediate risk values.
5.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following three
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
5-6
-------
Table 5-3. Daily and Seasonal Averages for the Pollutants of Interest for the Arizona Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
Phoenix, Arizona - PXSS
Arsenic (PM10)
Hexavalent Chromium
Manganese (PM10)
59
58
59
59
59
59
0.64
0.13
18.08
0.11
0.04
2.31
0.88
0.18
24.22
0.28
0.10
4.27
0.41
0.12
13.70
0.05
0.03
2.23
0.47
0.13
16.59
0.08
0.12
5.19
0.77
0.10
17.72
0.22
0.02
4.54
-------
5.4.1 Pearson Correlation Analysis
Table 5-4 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the PXSS monitoring site. (Refer
to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered from Table 5-4:
• The pollutants of interest for PXSS exhibited weak correlations with the selected
meteorological parameters, indicating that these variables have little effect on
concentrations of the pollutants of interest.
5.4.2 Composite Back Trajectory Analysis
Figure 5-3 is a composite back trajectory map for the PXSS monitoring site for the days
on which sampling occurred. Each line represents the 24-hour trajectory along which a parcel of
air traveled toward the monitoring site on a sampling day. Each concentric circle around the site
in Figure 5-3 represents 100 miles.
The following observations can be made from Figure 5-3:
• The back trajectories originated from a variety of directions at PXSS.
• The 24-hour airshed domain was somewhat smaller at PXSS than other UATMP
sites;
• 72 percent of the trajectories originated within 200 miles of the site and 90 percent
within 300 miles from the PXSS monitoring site.
• One trajectory originated as far away as northern Nevada, greater than 500 miles
away.
5.4.3 Wind Rose Analysis
Hourly wind data from the Sky Harbor International Airport near the PXSS monitoring
site were uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT
produces a graphical wind rose from the wind data. A wind rose shows the frequency of wind
directions about a 16-point compass, and uses different shading to represent wind speeds.
Figure 5-4 is the wind rose for the PXSS monitoring site on days sampling occurred.
5-8
-------
Table 5-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Arizona
Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar Wind
Speed
Phoenix, Arizona - PXSS
Arsenic (PM10)
Hexavalent Chromium
Manganese (PM10)
59
58
59
-0.22
-0.03
-0.13
-0.27
-0.04
-0.21
-0.08
-0.10
-0.30
-0.21
-0.08
-0.27
0.26
-0.13
-0.26
0.31
-0.03
0.34
-0.31
-0.16
-0.30
-------
Figure 5-3. Composite Back Trajectory Map for PXSS
o
-------
Figure 5-4. Wind Rose for PXSS Sampling Days
WEST
25%
20%
15%
SOUTH,-"
WIND SPEED
(Knots 3
| | >= 22
^| 17 • 21
I I 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 15.91%
-------
Observations from Figure 5-4 include:
• Hourly winds were predominantly out of the east (22 percent of observations) and west
(10 percent) on sampling days.
• Wind speeds tended to range from 7 to 11 knots on days that samples were collected (30
percent of observations).
• Calm winds (<2 knots) were observed for 16 percent of the observations.
5.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could
not be performed as this site did not sample for VOC. A mobile tracer analysis could not be
performed as this site did not sample for SNMOC.
5.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Maricopa County, AZ were obtained
from the Arizona Department of Transportation and the U.S. Census Bureau, and are
summarized in Table 5-5. Table 5-5 also includes a vehicle registration to county population
ratio (vehicles per person). In addition, the population within 10 miles of each site is presented.
An estimation of 10-mile vehicle registration was computed using the 10-mile population
surrounding the monitor and the vehicle registration ratio. Finally, Table 5-5 contains the
average daily traffic information, which represents the average number of vehicles passing the
monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 5-5 include:
• Compared to other UATMP sites, the county population in and around PXSS is near
the top, second only to the Chicago area.
• PXSS also has the highest county-level vehicle registration of any UATMP site.
• Although the Phoenix area is one of several large metropolitan areas included in the
UATMP, the average daily traffic count is very low compared to other UATMP sites.
Most of the other sites with low traffic counts are in fairly rural areas. Given that the
PXSS monitoring site is considered a residential area and is located in an urban-city
center setting, it is possible this number is underestimated.
5-12
-------
Table 5-5. Motor Vehicle Information for the Arizona Monitoring Site
Site
PXSS
2006 Estimated
County Population
3,768,123
Number of
Vehicles
Registered
3,682,234
Vehicles per Person
(Registration:
Population)
0.98
Population
Within 10 Miles
1,471,887
Estimated
10 Mile Vehicle
Ownership
1,438,337
Traffic Data
(Daily
Average)
250
-------
5.6 Trends Analysis
A trends analysis could not be performed for PXSS as this site has not participated in the
UATMP for three consecutive years.
5.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
PXSS and where the annual average concentrations could be calculated (refer to Section 3.3.5
regarding the definition of an annual average). Annual averages, theoretical cancer and
noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 5-6. Additionally,
the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA for the pollutants
that failed at least one screen at PXSS were retrieved and are also presented in Table 5-6. The
NATA data is presented for the census tract where the monitoring site is located.
The census tract information for the PXSS site is as follows:
• The PXSS monitoring site is located in census tract 04013108902.
• The census tract population for the census tract where the PXSS monitoring site is
located was 5,222, which represents less than 1 percent of the county population in
2000.
The following observations can be made from Table 5-6:
• With the exception of manganese, all of the annual averages were less than 0.01
|ig/m3.
• Based on these annual average concentrations, arsenic and hexavalent chromium
exhibited cancer risks greater than 1 in a million (2.74 and 1.58 in-a-million,
respectively).
• Manganese exhibited the highest noncancer HQ (0.36).
• Each of the NATA-modeled concentrations for pollutants that failed at least one
screen was less than 0.01 |ig/m3,which was similar to the annual averages.
5-14
-------
Table 5-6. Chronic Risk Summary for the Monitoring Site in Arizona
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
Phoenix, Arizona (PXSS) - Census Tract ID 04013108902
Arsenic*
Cadmium*
Hexavalent Chromium
Manganese*
Nickel*
0.0043
0.0018
0.012
NR
0.00016
0.00003
0.00002
0.0001
0.00005
0.000065
0.01
<0.01
0.01
0.01
O.01
0.05
0.02
0.37
NR
0.02
0.01
O.01
0.01
0.01
O.01
0.01 ±0.01
O.01 ±0.01
0.01 ±0.01
0.02 ±0.01
O.01 ±0.01
2.74
0.24
1.58
NR
0.22
0.02
0.01
0.01
0.36
0.02
*Metals sampled at PXSS were sampled with PM10 filters.
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
-------
• In terms of cancer risk, the highest risk for a pollutant that failed at least one screen
was calculated for hexavalent chromium (0.37 in-a-million). All the rest were less
than 0.10 in-a-million.
• The NATA-modeled cancer risks tended to be an order of magnitude less than the
cancer risks calculated from the annual averages.
• All of the NATA noncancer hazard quotients were less than 0.01, suggesting very
little risk for noncancer health affects.
5.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 5-7 and 5-8 present a risk-
based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 5-7 presents the 10 pollutants with the highest emissions from the 2002 NEI,
the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with the
highest cancer risk (in-a-million) as calculated from the annual average. Table 5-8 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer table, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer and noncancer risk based on each site's annual average is limited to those pollutants for
which each respective site sampled. In addition, the highest cancer and noncancer risks based on
annual averages are limited to those pollutants failing at least one screen.
The following observations can be made from Table 5-7:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor and the
highest cancer toxicity-weighted emissions for Maricopa County.
• Seven of the top 10 pollutants (benzene, acetaldehyde, tetrachloroethylene, 1,3-
dichloropropene, 1,3-butadiene, naphthalene, and/?-dichlorobenzene) appeared on both
the highest emitted list and the highest toxicity-weighted emissions list, indicating that
most of the highest emitted pollutants are also the most toxic.
• PXSS did not sample for VOC, carbonyls, or SVOC and therefore, cancer risks based on
annual averages for most of these pollutants cannot be assessed at this time. However,
lead, arsenic, and hexavalent chromium, which were sampled for at PXSS, were listed in
the top 10 toxicity-weighted emissions.
5-16
-------
Table 5-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for PXSS
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(for Maricopa County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Maricopa County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for PXSS)
Pollutant
Cancer Risk
(in-a-million)
Phoenix, Arizona - PXSS
Benzene
Formaldehyde
Acetaldehyde
Tetrachloroethylene
1 , 3 -Dichloropropene
1,3 -Butadiene
Dichloromethane
Naphthalene
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15 -PAH
1,914.42
1,040.74
373.93
280.30
238.49
237.53
162.04
138.65
123.56
14.67
Benzene
Lead
1,3 -Butadiene
Naphthalene
Arsenic
Tetrachloroethylene
£>-Dichlorobenzene
1 , 3 -Dichloropropene
Hexavalent Chromium
Acetaldehyde
1.49E-02
1.13E-02
7.13E-03
4.71E-03
1.69E-03
1.65E-03
1.36E-03
9.54E-04
8.61E-04
8.23E-04
Arsenic
Hexavalent Chromium
Cadmium
Nickel
2.74
1.58
0.24
0.22
-------
Table 5-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for
PXSS
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Maricopa County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Maricopa County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for PXSS)
Pollutant
Noncancer
Risk
(HQ)
Phoenix, Arizona - PXSS
Toluene
Xylenes
Benzene
Methyl Tert-Butyl Ether
Methanol
Hexane
Formaldehyde
Ethylbenzene
Methyl Ethyl Ketone
1,1,1 -Trichloroethane
5,862.72
4,195.84
,914.42
,700.77
,263.87
,100.16
,040.74
925.98
781.84
634.12
Acrolein
1,3 -Butadiene
Formaldehyde
Bromomethane
Benzene
Naphthalene
Xylenes
Acetaldehyde
Cyanide
Cadmium
2,930,122.29
118,762.60
106,198.46
66,526.05
63,814.03
46,217.08
41,958.37
41,547.57
38,836.22
21,408.23
Manganese
Arsenic
Nickel
Cadmium
Hexavalent Chromium
0.36
0.02
0.02
0.01
<0.01
oo
-------
• Arsenic and hexavalent chromium were listed first and second for highest cancer risk
based on the annual average for PXSS (2.74 and 1.58 in-a-million, respectively).
• Because lead did not fail any screens at PXSS it was excluded from this analysis.
The following observations can be made from Table 5-8:
• Although toluene was the highest emitted pollutant (by mass) with a noncancer risk
factor, it does not rank in the top 10 pollutants based on toxi city-weighted emissions.
• Acrolein has the highest noncancer toxicity- weighted emissions, but does not appear in
the list of highest emitted pollutants.
• Only three pollutants (xylenes, benzene, and formaldehyde) appear on both the top 10
emitted pollutants and top 10 toxi city-weighted emissions lists.
• Because PXSS did not sample for VOC, carbonyls, or SVOC and therefore, a comparison
of noncancer risks based on annual averages for these pollutants cannot be assessed at
this time.
• Cadmium was the only pollutant that failed screens at PXSS and has one of the top 10
highest noncancer toxicity-weighted emissions. The noncancer HQ for cadmium based
on the annual average at PXSS was very low (0.01).
Arizona Pollutant Summary
• The pollutants of interest for the Arizona site were manganese, arsenic, and hexavalent
chromium.
• Manganese had the highest daily average at PXSS.
• No pollutants exceeded either of the short-term risk factors.
5-19
-------
6.0 Site in Colorado
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Grand Junction, Colorado (GPCO). Figure 6-1 is a topographical map showing the
monitoring site in its urban location. Figure 6-2 identifies point source emission locations within
10 miles of this site as reported in the 2002 NEI for point sources. The Grand Junction site is
surrounded by numerous point sources, mostly located to the northwest, north, and northeast of
the site. A large number of point sources near GPCO fall into the liquids distribution source
category.
Grand Junction is located in a mountain valley on the west side of the Rockies. This
location can help protect the area from dramatic weather changes. The area tends to be rather
dry and winds tend to flow out of the east-southeast on average, due to the valley breeze effect.
Valley breezes occur as the sun heats up the side of a mountain. The warm air rises, creating a
current that will move up the valley walls (Ruffner and Bair, 1987).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the GPCO monitoring site is Walker Field Airport (WBAN 23066). Table 6-1 presents
average meteorological conditions of temperature (average maximum and average), moisture
(average dew point temperature, average wet-bulb temperature, and average relative humidity),
pressure (average sea level pressure), and wind information (average scalar wind speed) for the
entire year and on days samples were collected. Also included in Table 6-1 is the 95 percent
confidence interval for each parameter. As shown in Table 6-1, average meteorological
conditions on sampling days were fairly representative of average weather conditions throughout
the year.
6.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Colorado
monitoring site. As described in Section 3.1.4, the methodology for evaluating pollutants of
6-1
-------
Figure 6-1. Grand Junction, Colorado (GPCO) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
6-2
-------
Figure 6-2. Facilities Located Within 10 Miles of GPCO
fvlesa County
Nose; Due to facility density and collocation, the lc*a) facilities
displayed may noi represenl all facilities wilhin the area of interest.
Legend
••&• GPCO UATMP site
10 mile radius
Source Category Group (No. of Facilities)
A Agricultural Services Facility (1)
± Automobile Dealers (1)
* Automotive Repair, Services, & Parking (3)
c Chemicals & Allied Products Facility (2)
D Fabricated Metal Products Facility (1)
F Fuel Combustion Industrial Facility (4)
+ Health Services Facility (1)
L Liquids Distribution Industrial Facility (52}
County boundary
B Mineral Products Processing Industrial Facility (1)
P Miscellaneous Processes Industrial Facility (7)
P Petroleum/Nat. Gas Prod. & Refining Industrial Facility (1)
Y Rubber & Miscellaneous Plastic Products Facility (1)
s Surface Coating Processes Industrial Facility {6}
•f Transportation by Air (3)
T Waste Treatment & Disposal Industrial Facility (3)
'; Water Transportation Facility (1)
t Wholesale Trade {1}
6-3
-------
Table 6-1. Average Meteorological Conditions near the Monitoring Site in Colorado
Site
GPCO
WBAN
23066
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(»F)
65.40
±2.12
64.15
±5.17
Average
Temperature
(OF)
53.29
±1.94
52.34
±4.66
Average
Dew Point
Temperature
(°F)
27.92
±1.32
27.14
±3.22
Average
Wet Bulb
Temperature
(»F)
41.31
±1.30
40.60
±3.13
Average
Relative
Humidity
(%)
46.02
±2.11
45.95
±5.08
Average
Sea Level
Pressure
(mb)
1015.49
±0.82
1016.08
±2.07
Average
Scalar Wind
Speed
(kt)
6.86
±0.27
6.97
±0.70
-------
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. The GPCO site sampled for carbonyls and
VOCs only. Table 6-2 presents the pollutants that failed at least one screen at GPCO.
The following observations are shown in Table 6-2:
• A total of 412 measured concentrations and thirteen pollutants failed screens.
• The screening process at GPCO resulted in eight pollutants of interest: formaldehyde (61
failed screens), acetaldehyde (61), benzene (61), carbon tetrachloride (59), 1,3-butadiene
(56), acrolein (45), tetrachloroethylene (37), and/>-dichlorobenzene (17).
• Of the eight pollutants of interest, 100 percent of the measured detections of
acetaldehyde, benzene, formaldehyde, acrolein, and 1,3-butadiene exceeded the screening
values.
• Of pollutants failing at least one screen, sixty-eight percent of the measured
concentrations failed screens.
Table 6-2. Comparison of Measured Concentrations and EPA Screening Values for the
Colorado Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Grand Junction, Colorado - GPCO
Formaldehyde
Acetaldehyde
Benzene
Carbon Tetrachloride
1,3 -Butadiene
Acrolein
Tetrachloroethylene
£>-Dichlorobenzene
Xylenes
Hexavalent Chromium
Acrylonitrile
Hexachloro- 1 , 3 -butadiene
Dichloromethane
Total
61
61
61
59
56
45
37
17
5
4
3
2
1
412
61
61
61
60
56
45
52
37
61
49
3
2
57
605
100.00
100.00
100.00
98.33
100.00
100.00
71.15
45.95
8.20
8.16
100.00
100.00
1.75
68.10
14.81
14.81
14.81
14.32
13.59
10.92
8.98
4.13
1.21
0.97
0.73
0.49
0.24
14.81
29.61
44.42
58.74
72.33
83.25
92.23
96.36
97.57
98.54
99.27
99.76
100.00
6-5
-------
6.2 Concentration Averages
Three types of concentration averages were calculated for the following subsections:
daily, seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
a season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal averages are presented in
Table 6-3. Annual averages are presented and discussed in further detail in later sections.
The following observations are shown in Table 6-3:
• Formaldehyde had the highest daily average concentration by mass at GPCO (4.00 ±
0.32 |ig/m3), followed by acetaldehyde (2.35 ± 0.20 |ig/m3) and benzene (1.85 ± 0.23
|ig/m3).
• Formaldehyde concentrations were also the highest among each season, ranging from
3.14 ± 0.52 |ig/m3 in spring to 5.22 ± 0.49 |ig/m3 in summer.
• While formaldehyde was highest in the summer, carbon tetrachloride was highest in
the summer and autumn, and benzene and 1,3-butadiene were highest in autumn and
winter.
• Acetaldehyde, benzene, and formaldehyde were detected in every sample collected at
GPCO, while acrolein and/>-dichlorobenzene were detected in less than two-thirds of
the samples collected.
6.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for GPCO was evaluated using ATSDR
short-term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is
defined as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15
to 364 days. It is useful to compare preprocessed daily measurements to the short-term MRL
and REL factors, as well as compare seasonal averages to the intermediate MRL. Of the thirteen
6-6
-------
Table 6-3. Daily and Seasonal Averages for the Pollutants of Interest for the Colorado Monitoring Site
Pollutant
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Tetrachloroethylene
#of
Measured
Detections
61
45
61
56
60
37
61
52
#of
Samples
61
61
61
61
61
61
61
61
Daily
Avg
(Ug/m3)
2.35
0.80
1.85
0.21
0.59
0.14
4.00
0.40
Conf.
Int.
0.20
0.19
0.23
0.04
0.06
0.03
0.32
0.10
Winter
Avg
(Ug/m3)
2.54
0.35
2.47
0.32
0.49
0.04
3.58
0.52
Conf.
Int.
0.38
0.10
0.48
0.07
0.08
0.02
0.43
0.16
Spring
Avg
(Ug/m3)
1.69
NR
1.18
0.10
0.43
NR
3.14
0.16
Conf.
Int.
0.35
NR
0.25
0.04
0.09
NR
0.52
0.09
Summer
Avg
(Ug/m3)
2.63
0.62
1.45
0.10
0.71
0.11
5.52
0.32
Conf.
Int.
0.28
0.30
0.33
0.02
0.10
0.05
0.49
0.27
Autumn
Avg
(Ug/m3)
2.52
1.15
2.26
0.26
0.72
0.18
3.77
0.37
Conf.
Int.
0.37
0.41
0.41
0.07
0.11
0.06
0.41
0.10
NR = Not reportable due to low number of measured detections.
-------
pollutants with at least one failed screen, only acrolein exceeded both the acute and intermediate
risk values, and its non-chronic risk is summarized in Table 6-4.
The following observations about acrolein are shown in Table 6-4:
• All forty-five acrolein measured detections were greater than the ATSDR acute risk
value of 0.11 |ig/m3 and the California REL risk value of 0.19 |ig/m3.
• The average daily acrolein concentration was 0.80 ± 0.19 |ig/m3, which is almost four
times the California REL value.
• For the intermediate acrolein risk, seasonal averages were compared to the ATSDR
intermediate value of 0.09 |ig/m3. The winter, summer, and autumn seasonal
averages were each greater than the ATSDR intermediate risk level. Acrolein had
fewer than seven measured detections during the spring at GPCO (6), therefore, no
spring average was calculated.
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of daily
concentration and daily average wind direction. Figure 6-3 is a pollution rose for acrolein for
GPCO.
Observations gleaned from the acrolein pollution rose include:
• All acrolein concentrations exceeded the acute risk factors, indicated by a dashed
(CALEPA REL) and solid line (ATSDR MRL).
• The acrolein concentrations on the pollution rose were predominantly associated with
southeast and easterly winds, which may indicate that sources of acrolein are located
in these directions from the site.
• The highest concentration of acrolein occurred on September 2, 2006 with a westerly
wind.
• GPCO is situated near several roadways and a railroad that runs east-northeast to
west-southwest in relation to the monitoring site, and then curves northwestward just
south of the site (Figure 6-1). Additionally, a number of point sources are located
both to the west and the east of the monitoring site (Figure 6-2).
6.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following three
meteorological analyses: Pearson correlation coefficients between meteorological parameters
6-8
-------
Table 6-4. Non-Chronic Risk Summary for the Colorado Monitoring Site
Site
GPCO
Method
TO- 15
Pollutant
Acrolein
Daily
Avg
(Hg/m3)
0.80
±0.19
ATSDR
Short-
term
MRL
(Hg/m3)
0.11
# of ATSDR
MRL
Exceedances
45
CAL
EPA
REL
Acute
(Hg/m3)
0.19
# of CAL
EPA REL
Exceedances
45
ATSDR
Intermediate-
term MRL
(Hg/m3)
0.09
Winter
Avg
(Ug/m3)
0.35
±0.10
Spring
Avg
(Ug/m3)
NR
Summer
Avg
(Ug/m3)
0.62
±0.30
Autumn
Avg
(Ug/m3)
1.15
±0.41
NR = Not reportable due to low number of measured detections.
-------
Figure 6-3. Acrolein Pollution Rose for GPCO
4.5
4.0
3.5
3.0
2.5
2.0
1.5
| 1-°
2
c 0.5
01
o
O 00
0
|0.5
3 1.0
Q_
1.5
2.0
2.5
3.0
3.5
4.0
4R
____________________________________________
NW N
— CA EPA REL (0.19 ng/m3)
ATSDR MRL (0. 1 1 ng/m3)
-
-
-
-
-
W ** t-'
• ' ' ' ' ' '"5;
-
-
-
-
-
-
-
sw s
_________^
NE
*
• E
^j^^A ^ * '
* ** *
*
*
Daily Avg Cone = 0.80 ±0.1 9 j^g/mS SE
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
Pollutant Concentration
-------
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
6.4.1 Pearson Correlation Analysis
Table 6-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters at the GPCO monitoring site. (Refer
to Section 3.1.6 for more information on Pearson Correlations.)
The following observations are gathered from Table 6-5:
• Formaldehyde exhibited strong correlations with maximum, average, and wet bulb
temperatures, indicating that concentrations of formaldehyde tend to increase with
increasing temperature and moisture content.
• 1,3-Butadiene exhibited strong negative correlations with these same parameters,
which indicates that concentrations of 1,3-butadiene tend to increase with decreasing
temperature and moisture content.
• While most of the wind speed correlations were weak, all were negative. This
indicates that decreasing winds speeds correlate to increasing concentrations of the
pollutants of interest.
6.4.2 Composite Back Trajectory Analysis
Figure 6-4 is a composite back trajectory map for the GPCO monitoring site for the days
on which sampling occurred. Each line represents the 24-hour trajectory along which a parcel of
air traveled toward the monitoring site on a sampling day. Each concentric circle around the site
in Figure 6-4 represents 100 miles.
The following observation can be made from Figure 6-4:
• The back trajectories originated from a variety of directions at GPCO, although less
frequently from the northeast, east, and southeast.
• The 24-hour airshed domain was somewhat smaller at GPCO than other UATMP
sites.
• 53 percent of the trajectories originated within 200 miles of the site, and 79 percent
within 300 miles from the GPCO monitoring site.
6-11
-------
Table 6-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Colorado
Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Grand Junction, Colorado - GPCO
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
/>-Dichlorobenzene
Formaldehyde
Tetrachloroethylene
61
45
61
56
60
37
61
52
0.18
0.10
-0.37
-0.52
0.39
0.11
0.63
-0.14
0.16
0.10
-0.40
-0.55
0.41
0.10
0.63
-0.16
0.12
0.19
-0.11
-0.38
0.48
0.29
0.46
-0.03
0.14
0.15
-0.34
-0.53
0.46
0.19
0.60
-0.12
-0.08
0.07
0.36
0.32
-0.03
0.11
-0.33
0.13
0.19
-0.17
0.42
0.43
-0.16
-0.03
-0.14
0.25
-0.37
-0.02
-0.46
-0.48
0.02
-0.07
-0.07
-0.12
to
-------
Figure 6-4. Composite Back Trajectory Map for GPCO
-------
• Trajectories originated as far away as central Idaho, greater than 400 miles.
6.4.3 Wind Rose Analysis
Hourly wind data from the Walker Field Airport near the GPCO monitoring site were
uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces a
graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
about a 16-point compass, and uses different shading to represent wind speeds. Figure 6-5 is the
wind rose for the GPCO monitoring site on days that sampling occurred.
Observations from Figure 6-5 include:
• Hourly winds were predominantly out of the east-southeast (15 percent of
observations), east (13 percent), and southeast (11 percent) on sampling days.
• Wind speeds ranged from 7 to 11 knots on sampling days (36 percent of
observations).
• Calm winds (<2 knots) were recorded for 11 percent of the observations.
6.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as this site did not sample for SNMOC.
6.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Mesa County, CO were obtained from
the Colorado Department of Revenue and the U.S. Census Bureau, and are summarized in
Table 6-6. Table 6-6 also includes a vehicle registration to county population ratio (vehicles per
person). In addition, the population within 10 miles of each site is presented. An estimation of
10-mile vehicle registration was computed using the 10-mile population surrounding the monitor
and the vehicle registration ratio. Finally, Table 6-6 contains the average daily traffic
information, which represents the average number of vehicles passing the monitoring sites on the
nearest roadway to each site on a daily basis.
6-14
-------
Figure 6-5. Wind Rose for GPCO Sampling Days
WEST
20%
16%
12%
SOUTH,-"
WIND SPEED
(Knots 3
| | >= 22
^| 17 • 21
I I 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 11.29%
-------
Table 6-6. Motor Vehicle Information for the Colorado Monitoring Site
Site
GPCO
2006 Estimated
County Population
134,189
Number of
Vehicles
Registered
154,175
Vehicles per Person
(Registration:
Population)
1.15
Population
Within 10 Miles
111,141
Estimated 10
mile Vehicle
Ownership
127,694
Traffic Data
(Daily
Average)
19,572
Oi
Oi
-------
Observations gleaned from Table 6-6 include:
• Compared to other UATMP sites, the population and vehicle registration count near
GPCO is low to mid-range; however, GPCO has one of the highest estimated vehicle
registration-to-population ratios (1.15).
• The average daily traffic count falls in the middle of the range compared to other
UATMP sites.
• The GPCO monitoring site is located in a commercial area and is located in an urban-
city center setting.
6.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compared them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road or motor vehicle emissions.
The BTEX table and figure show the following:
• The BTEX ratios generally resemble those of the roadside study.
• The benzene-ethylbenzene ratio (4.04 ± 0.34) and the xylenes-ethylbenzene ratio
(4.61 ±0.15) were closer together than the roadside study ratios (2.85 and 4.55,
respectively).
• The toluene-ethylbenzene ratio for GPCO (7.20 ± 0.40) was higher than that of the
roadside study (5.85).
6.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. The
GPCO site has participated in the UATMP since 2004. Figure 6-6 presents the trends analysis
for formaldehyde, benzene, and 1,3-butadiene for GPCO.
6-17
-------
Figure 6-6. Comparison of Yearly Averages for the GPCO Monitoring Site
3.5 --
3 -
2.5 --
c
a)
o
O
O
a)
1.5
00
1 --
0.5 -
2004
2005
Year
2006
D1,3-Butadiene
I Benzene
D Formaldehyde
-------
The following observations can be made from Figure 6-6:
• Concentrations of 1,3-butadiene at GPCO have changed little over the last three
years.
• Concentrations of benzene have decreased slightly since 2004, although the
overlapping confidence intervals indicate the decrease was not significant.
• The formaldehyde concentration has been steadily increasing since 2004. However,
the large confidence interval in 2004 makes it difficult to determine if the increase
was significant. This average concentration contained several outliers.
6.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
GPCO and where the annual average concentrations could be calculated (refer to Section 3.3.5
regarding the definition of an annual average). Annual averages, theoretical cancer and
noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 6-7. Additionally,
the pollutants of interest are bolded. Finally, data from EPA's 1999 NAT A were retrieved and
are also presented in Table 6-7. The NATA data is presented for the census tract where the
monitoring site is located.
The census tract information for GPCO is as follows:
• The GPCO monitoring site is located in census tract 08077000800.
• The census tract population for the census tract where the GPCO monitoring site is
located was 5,845, which represents about 5 percent of the county population in 2000.
The following observations can be made from Table 6-7:
• The pollutants with the top four annual averages by mass concentration at GPCO
were xylenes (5.40 ± 0.81 |ig/m3), formaldehyde (4.00 ± 0.32 |ig/m3), acetaldehyde
(2.35 ± 0.20 |ig/m3), and benzene (1.85 ± 0.23 |ig/m3).
• Yet the pollutants with the highest cancer risk were benzene, carbon tetrachloride,
and acrylonitrile (14.41, 8.77, and 5.96 in-a-million, respectively).
• Only acrolein exhibited a noncancer HQ greater than 1 (31.26). All other noncancer
risks were less than 0.50.
• Formaldehyde, acetaldehyde, benzene, and xylenes exhibited the highest NATA-
modeled concentrations.
6-19
-------
Table 6-7. Chronic Risk Summary for the Monitoring Site in Colorado
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(Hg/m3)
Cancer Risk Noncancer
(in-a- Risk
million) (HQ)
Grand Junction, Colorado (GPCO) - Census Tract 08077000800
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
Dichloromethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Hexavalent Chromium
Tetrachloroethylene
Xylenes
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
0.00000047
5.5E-09
0.000022
0.012
0.0000059
NR
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
1
0.0098
0.09
0.0001
0.27
0.1
0.58
0.02
<0.01
0.56
0.04
0.21
0.01
0.21
0.73
<0.01
0.01
0.07
0.53
1.28
NR
0.15
4.39
1.25
3.19
0.14
0.10
0.01
0.03
0.03
0.42
NR
0.06
1.04
O.01
0.02
0.02
0.01
O.01
0.01
0.07
O.01
0.01
O.01
0.01
2.35 ±0.20
0.63 ±0.16
0.09 ±0.03
1.85 ±0.23
0.20 ±0.04
0.58 ±0.06
0.09 ±0.03
0.41 ±0.09
4.00 ±0.32
0.07 ±O.01
0.01
0.34 ±0.09
5.40 ±0.81
5.17
NR
5.96
14.41
5.91
8.77
0.99
0.19
0.02
1.59
0.36
2.03
NR
0.26
31.26
0.04
0.06
0.1
0.01
O.01
0.01
0.41
O.01
0.01
O.01
0.05
to
o
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made
-------
• Although these four pollutants were the same as the ones exhibited the highest annual
averages, the NATA-modeled concentrations tended to be lower by an order of
magnitude.
• In terms of cancer risk, the top three pollutants identified by NATA in the GPCO
census tract were benzene (4.39 in-a-million risk), carbon tetrachloride (3.19), and
acetaldehyde(1.28).
• Acrolein was the only pollutant in the GPCO census tract to have a noncancer hazard
quotient greater than 1.0 (1.04). Most noncancer hazard quotients were less than
0.10, suggesting very little risk for noncancer health affects, with the exception of
acrolein.
6.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 6-8 and 6-9 present a risk-
based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 6-8 presents the 10 pollutants with the highest emissions from the 2002 NEI,
the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with the
highest cancer risk (in-a-million) as calculated from the annual average. Table 6-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer table, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer and noncancer risk based on each site's annual average is limited to those pollutants for
which each respective site sampled. In addition, the highest cancer and noncancer risks based on
annual averages are limited to those pollutants failing at least one screen.
The following observations can be made from Table 6-8:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor and the
highest cancer toxicity-weighted emissions for Mesa County.
• Benzene had the highest cancer risk based on annual averages at GPCO.
• Although formaldehyde was the second highest emitted pollutant in Mesa County, the
cancer risk factor is low; this pollutant was not listed on either the highest toxicity-
weighted emissions or the cancer risks based on annual averages.
6-21
-------
Table 6-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for GPCO
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(for Mesa County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Mesa County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for GPCO)
Pollutant
Cancer Risk
(in-a-million)
Grand Junction, Colorado - GPCO
Benzene
Formaldehyde
Dichloromethane
Acetaldehyde
1,3 -Butadiene
Naphthalene
Poly cyclic Organic Matter as 15 -PAH
Tetrachloroethylene
Trichloroethylene
Vinyl Chloride
156.46
59.48
20.67
19.49
15.79
4.23
3.03
2.92
1.50
1.19
Benzene
Lead
1,3 -Butadiene
Arsenic
Poly cyclic Organic Matter as 15 -PAH
Naphthalene
Hexavalent Chromium
Polycyclic Organic Matter as 7-PAH
Acrylonitrile
Acetaldehyde
1.22E-03
5.01E-04
4.74E-04
1.89E-04
1.67E-04
1.44E-04
9.64E-05
6.09E-05
5.94E-05
4.29E-05
Benzene
Carbon Tetrachloride
Acrylonitrile
1,3 -Butadiene
Acetaldehyde
Tetrachloroethylene
Hexachloro- 1 , 3 -butadiene
/>-Dichlorobenzene
Hexavalent Chromium
Dichloromethane
14.41
8.77
5.96
5.91
5.17
2.03
1.59
0.99
0.36
0.19
to
to
-------
Table 6-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with
Noncancer RfCs for GPCO
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Mesa County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Mesa County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for GPCO)
Pollutant
Noncancer
Risk
(HQ)
Grand Junction, Colorado - GPCO
Toluene
Xylenes
Benzene
Formaldehyde
Hexane
Methanol
Ethylbenzene
Hydrogen Fluoride
Methyl Ethyl Ketone
Dichloromethane
388.94
232.09
156.46
59.48
57.09
55.39
53.46
36.34
29.47
20.67
Acrolein
1,3 -Butadiene
Manganese
Formaldehyde
Benzene
Xylenes
Acetaldehyde
Cyanide
Arsenic
Naphthalene
153,654.69
7,896.97
6,135.14
6,069.34
5,215.18
2,320.91
2,165.68
1,554.17
1,461.84
1,410.73
Acrolein
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Benzene
Xylenes
Acrylonitrile
Carbon Tetrachloride
Tetrachloroethylene
Hexachloro- 1 , 3 -butadiene
31.26
0.41
0.26
0.10
0.06
0.05
0.04
0.01
0.00
0.00
to
-------
• Lead, which followed benzene based on toxicity-weighted emissions, was not
sampled for at the GPCO monitoring site.
• In addition to benzene, two additional pollutants (acetaldehyde and 1,3-butadiene)
appeared on all three lists.
• Dichloromethane, which ranked third highest for total emissions in Mesa County, had
the tenth highest cancer risk based on annual averages at GPCO (0.19 in-a-million),
but does not have one of the 10 highest toxicity-weighted emissions.
The following observations can be made from Table 6-9:
• Although toluene was the highest emitted pollutant (by mass) with a noncancer risk
factor, it did not rank in the top 10 pollutants based on toxicity-weighted emissions.
• Acrolein had the highest noncancer toxicity-weighted emissions, but did not appear in
the list of highest emitted pollutants.
• Acrolein had the only noncancer HQ greater than 1 based on annual averages for
GPCO.
• Three pollutants (xylenes, benzene, and formaldehyde) appeared on all three "Top
10" lists.
Colorado Pollutant Summary
• The pollutants of interest at the Colorado site were acetaldehyde, acrolein, benzene,
1,5'-butadiene, carbon tetrachloride, formaldehyde, p-dichlorobenzene, and
tetrachloroethylene.
• Formaldehyde had the highest daily average for GPCO.
• Acrolein was the only pollutant to exceed either of the short-term risk factors.
6-24
-------
7.0 Site in Washington, B.C.
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Washington, D.C. (WADC). Figure 7-1 is a topographical map showing the monitoring
site in its urban location. Figure 7-2 identifies point source emission locations within 10 miles of
this site as reported in the 2002 NEI for point sources. The Washington, D.C. site is surrounded
by a handful of industrial point sources, with very few actually residing in the District itself.
Several of these sources fall into the fuel combustion or utility boiler source category, although
an electric, gas, and sanitary service facility resides fairly close to the WADC site.
Located on the Potomac River that divides Virginia and Maryland, the capital enjoys all
four seasons, although its weather is somewhat variable. Summers are warm and often humid, as
southerly winds prevail, which can be accentuated by the urban heat island effect. Winters are
typical of the Mid-Atlantic region, where cool, blustery air masses are common followed by a
fairly quick return to mild temperatures (Ruffner and Bair, 1987 and
http://en.wikipedia.org/wikiAVashington, D.C.).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the WADC monitoring site is Reagan National Airport (WBAN 13743). Table 7-1 presents
average meteorological conditions of temperature (average maximum and average), moisture
(average dew point temperature, average wet-bulb temperature, and average relative humidity),
pressure (average sea level pressure), and wind information (average scalar wind speed) for the
entire year and on days samples were collected. Also included in Table 7-1 is the 95 percent
confidence interval for each parameter. As shown in Table 7-1, average meteorological
conditions on sampling days were representative of average weather conditions throughout the
year.
7-1
-------
Figure 7-1. Washington, D.C. (WADC) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
7-2
-------
Figure 7-2. Facilities Located Within 10 Miles of WADC
.%
S" ,
r
'*
7T1i'n:r»v
\^-7^^^A
~i^- ( Jl
\ > , *"'->4-f / •'"
r%^7)&
" '\V^'i \T
' "^~. ,/J 'A IH w~ ~\
- -/'" "
\ V- "'"
x'i / >
1
1
/ .- ••' " '\
• - -/v " 'V—— -.
-\- " " / '
- '" " " " \ / \
', _,,-••-""" "l /^"^"^--^ \
• •'T i / P
, ' ' , / FI "••, •',-''
Montgoi'nery / . T) " '
, c~nty \ 1 . «p - ' " " ' .;
- '' "' ' ' C, i
"'•'./ S ' , \
*V. '(
•l '• ''.
,( District of ( i \ ..
— - / , Columbia '. ' X ' - '' ' \
F--, /' •. F' ~":^s\ -"' . \
' '-' *' ^T'~ ' " " " *''^~ " !-
'• ,•'' '••-,.-,-•'" '', 8 \> ' J
' . ~ ./''" " ''' -.. i ,,'' ' Prince George's ' \
" ' \ , / \ County i'
, / Arlington \ \ R i ,/' /,
County '• , ._ \
\ Falls Church p ', Y \ 8 '
\ '•• County''-,, , \ i / '' . -• 7"
'. Fairfax
' County
.,
j _ ' - "
024
Miles
Legend
1 '''-X ' . LJ \. /'- " " " ">
f~" "" " \ - - ' "
, - , V -"""''• i.'1' '
" •:„ .. ../-X"V " i / •', •"
-- ~" '~% (,, Alexandria \ 1 / ^
,i CcKmty ,( j / i .-•*' !|
', " V-, .,-•- - — t— -,., Y i _,...---^ ' 1 e
.%--w--.,.. , "I I.----' '• ^^
~ -; - — \-~- -' ~" , ', £
-' ' " 1 !.!'( •• 'i\' f ! '••'. ,'•: ! ' W .»' '' ". s i i Vy' *!"" s's1!} Vv
Note; Due to facility density and collocation, the total facilities
displayed may not represent aB facilities within the area of interest.
:?;
t
_r,
i
10 mile radius | | County boundary
"K" WADC UATMP site
Source Category Group (NO. Of Facilities) P Miscellaneous Processes Industrial Facility (2)
E Electric. Gas, & Sanitary Services (2) @ paper & Allied Products (1)
R Printing & Publishing Facility (1)
5 Surface Coating Processes Industrial Facility (2)
0 Fabricated Metal Products Facility (1)
F Fuel Combustion Industrial Facility (5)
1 Incineration Industrial Facility (1)
L Liquids Distribution Industrial Facility {1}
8 Utility Boilers (3)
! Waste Treatment & Disposal Industrial Facility (1)
7-3
-------
Table 7-1. Average Meteorological Conditions near the Monitoring Site in Washington, D.C.
Site
WADC
WBAN
13743
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
67.18
± 1.65
67.23
±3.90
Average
Temperature (°F)
58.97
±1.57
59.19
±3.67
Average
Dew Point
Temperature
(»F)
45.69
±1.77
46.82
±3.86
Average
Wet Bulb
Temperature
(°F)
52.38
±1.48
52.87
±3.31
Average
Relative
Humidity
(%)
64.52
±1.53
66.89
±3.86
Average
Sea Level
Pressure
(mb)
1016.64
±0.70
1016.34
± 1.61
Average
Scalar Wind
Speed
(kt)
7.53
±0.31
7.26
±0.64
-------
7.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Washington,
D.C. monitoring site. As described in Section 3.1.4, the methodology for evaluating pollutants
of interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. Table 9-2 presents the pollutants that failed
at least one screen at WADC. The WADC site only sampled for hexavalent chromium.
The following observations are shown in Table 7-2:
• One of 40 hexavalent chromium concentrations failed screens. This is a 2.50 percent
failure rate.
Table 7-2. Comparison of Measured Concentrations and EPA Screening Values for the
Washington, D.C. Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Washington, D.C. - WADC
Hexavalent Chromium
Total
1
1
40
40
2.50
2.50
100.00
100.00
7.2 Concentration Averages
Three types of concentration averages were calculated for the following subsections:
daily, seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
a season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
7-5
-------
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal averages are presented in
Table 7-3. Annual averages are presented and discussed in further detail in later sections.
The following observations are shown in Table 7-3:
• The daily average concentration of hexavalent chromium for WADC was 0.041 ±
0.030 ng/m3.
• Seasonal hexavalent chromium averages wee available for each season.
• The winter, spring, and autumn seasonal averages were very similar to each other,
while the summer average was more than three times the other averages. However,
the confidence interval for the summer average indicates that this average was likely
influenced by outliers.
• The highest concentration recorded at WADC (0.645 ng/m3) was measured on July 4,
2006 and was an order of magnitude higher than any of the other concentrations
measured at WADC. This concentration was also the only one to exceed the risk
screening value (0.083 ng/m3).
7.3 Non-Chronic Risk Evaluation
Non-chronic risk based on the concentration data for WADC was evaluated using
ATSDR short-term (acute) and intermediate MRL and California EPA acute REL factors. Acute
risk is defined as exposures from 1 to 14 days while intermediate risk is defined as exposures
from 15 to 364 days. It is useful to compare preprocessed daily measurements to the short-term
MRL and REL factors, as well as compare seasonal averages to the intermediate MRL.
Hexavalent chromium does not have acute risk factors, therefore, acute risk could not be
evaluated. This pollutant did not exceed its intermediate risk value at WADC.
7.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following three
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
7-6
-------
Table 7-3. Daily and Seasonal Averages for the Pollutants of Interest for the Washington, D.C. Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
Washington, D.C. - WADC
Hexavalent Chromium
40
59
0.041
0.030
0.018
0.007
0.016
0.006
0.067
0.078
0.017
0.007
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
-------
7.4.1 Pearson Correlation Analysis
Table 7-4 presents the summary of Pearson correlation coefficients for hexavalent
chromium and select meteorological parameters for the WADC monitoring site. (Refer to
Section 3.1.6 for more information on Pearson correlations.) The calculated Pearson correlations
were weak.
7.4.2 Composite Back Trajectory Analysis
Figure 7-3 is a composite back trajectory map for the WADC monitoring site for the days
on which sampling occurred. Each line represents the 24-hour trajectory along which a parcel of
air traveled toward the monitoring site on a sampling day. Each concentric circle around the site
in Figure 7-3 represents 100 miles.
The following observations can be made from Figure 7-3:
• The back trajectories originated from a variety of directions at WADC, although most
frequently from the northwest.
• The 24-hour airshed domain is somewhat large at WADC, with trajectories
originating as far away Lake Michigan, greater than 600 miles away.
• However, 46 percent of the trajectories originated within 300 miles of the site; and 72
percent within 400 miles from the WADC monitoring site.
7.4.3 Wind Rose Analysis
Hourly wind data from the Reagan National Airport near the WADC monitoring site was
uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces a
graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
about a 16-point compass, and uses different shading to represent wind speeds. Figure 7-4 is the
wind rose for the WADC monitoring site on days sampling occurred.
Observations from Figure 7-4 include:
• Hourly winds were predominantly out of the south (20 percent of observations) on
sampling days.
• Calm winds (<2 knots) were less frequently observed at WADC than many other
UATMP sites (less than 8 percent of the measurements).
-------
Table 7-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Washington,
D.C. Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar Wind
Speed
Washington, D.C. - WADC
Hexavalent Chromium
40
0.24
0.22
0.26
0.25
0.10
-0.02
0.06
-------
Figure 7-3. Composite Back Trajectory Map for WADC
o
-------
Figure 7-4. Wind Rose for WADC Sampling Days
WEST
NORTH"
25%
20%
15%
10%
SOUTH.--'
EAST
WIND SPEED
(Knots)
| | >= 22
^| 17 - 21
I I 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 7.68%
-------
• Wind speeds ranged from 7 to 11 knots on days that samples were collected (40
percent of observations).
7.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could
not be performed as ERG did not analyze VOCs for this site. A mobile tracer analysis could not
be performed as this site did not sample for SNMOC.
7.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Washington, D.C. was obtained from
the District of Columbia Department of Motor Vehicles and the U.S. Census Bureau, and are
summarized in Table 7-5. Table 7-5 also includes a vehicle registration to county population
ratio (vehicles per person). In addition, the population within 10 miles of the site is presented.
An estimation of 10-mile vehicle registration was computed using the 10-mile population
surrounding the monitor and the vehicle registration ratio. Finally, Table 7-5 contains the
average daily traffic information, which represents the average number of vehicles passing the
monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 7-5 include:
• Compared to other UATMP sites, the District population near WADC is near the
middle of the range.
• WADC's 10-mile population is fourth highest of all UATMP sites, behind only
ELNJ, SPIL, and CANJ.
• WADC's vehicle registration is mid-to-low compared to other UATMP sites, but its
estimated 10-mile ownership estimate ranks 15th highest compared to other UATMP
sites.
• WADC's estimated vehicle per person ratio is one of the lowest of all the UATMP
sites.
• The average daily traffic count is also fairly high, ranking 8th compared to other
UATMP sites.
7-12
-------
Table 7-5. Motor Vehicle Information for the Washington, D.C. Monitoring Site
Site
WADC
2006 Estimated
County Population
581,530
Number of
Vehicles
Registered
230,000
Vehicles per Person
(Registration:
Population)
0.40
Population
Within 10 Miles
1,835,924
Estimated
10 Mile Vehicle
Ownership
726,123
Traffic Data
(Daily
Average)
75,800
-------
7.6 Trends Analysis
A trends analysis could not be performed for WADC as this site has not participated in
the UATMP for three consecutive years.
7.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
WADC and where the annual average concentrations could be calculated (refer to Section 3.3.5
regarding the definition of an annual average). Annual averages, theoretical cancer and
noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 7-6. The NATA
data is presented for the census tract where the monitoring site is located.
The census tract information for the WADC monitoring site is as follows:
• The WADC monitoring site is located in census tract 11001003301.
The population for the census tract where the WADC monitoring site is located was
2,707, which represents less than one percent of the District population in 2000.
The following observations can be made from Table 7-6:
• Both the NATA-modeled and annual average concentrations for hexavalent
chromium were less than 0.01 |ig/m3.
• In terms of cancer risk, the NATA-modeled and calculated cancer risks were very
similar (0.38 and 0.36 in-a-million, respectively).
• Both noncancer hazard quotients were less than 0.01, suggesting very little risk for
noncancer health affects due to hexavalent chromium.
7.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 7-7 and 7-8 present a risk-
based assessment of the District-level emissions based on cancer and noncancer toxicity,
respectively. Table 7-7 presents the 10 pollutants with the highest emissions from the 2002 NEI,
the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with the
7-14
-------
Table 7-6. Chronic Risk Summary for the Monitoring Site in Washington, D.C.
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
Washington, D.C. (WADC) - Census Tract ID 11001003301
Hexavalent Chromium
0.012
0.0001
0.01 0.38
0.01
0.01 ±0.01
0.36
0.01
-------
Table 7-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for WADC
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(for Washington, B.C.)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Washington, B.C.)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for WABC)
Cancer Risk
Pollutant (in-a-million)
Washington, B.C. - WABC
Benzene
Formaldehyde
Acetaldehyde
Tetrachloroethylene
1,3 -Butadiene
Trichloroethylene
£>-Dichlorobenzene
Dichloromethane
Naphthalene
Poly cyclic Organic Matter as 15 -PAH
205.68
111.05
38.27
35.18
24.78
16.05
12.18
8.86
5.81
1.50
Benzene
1,3 -Butadiene
Tetrachloroethylene
Naphthalene
£>-Dichlorobenzene
Polycyclic Organic Matter as 7-PAH
Acetaldehyde
Polycyclic Organic Matter as 15 -PAH
Arsenic
Ethylene Oxide
1.60E-03
7.44E-04
2.08E-04
1.98E-04
1.34E-04
8.95E-05
8.42E-05
8.23E-05
6.19E-05
4.90E-05
Hexavalent Chromium 0.36
-------
Table 7-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with
Noncancer RfCs for WADC
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Washington, B.C.)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Washington, B.C.)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for WABC)
Noncancer
Risk
Pollutant (HQ)
Washington, B.C. - WABC
Toluene
Methyl Tert-Butyl Ether
Xylenes
Benzene
Methanol
Formaldehyde
Ethylbenzene
1,1,1 -Trichloroethane
Hexane
Methyl Ethyl Ketone
462.57
362.58
311.31
205.68
198.99
111.05
69.19
60.49
57.94
52.73
Acrolein
1,3 -Butadiene
Formaldehyde
Chlorine
Cyanide
Benzene
Acetaldehyde
Xylenes
Naphthalene
2,4-Toluene Diisocyanate
323,975.52
12,392.33
11,331.58
8,575.00
7,315.67
6,856.00
4,252.49
3,113.14
1,936.65
1,206.11
Hexavalent Chromium 2.98E-04
-------
highest cancer risk (in-a-million) as calculated from the annual average. Table 7-8 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer table, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer and noncancer risk based on each site's annual average is limited to those pollutants for
which each respective site sampled. In addition, the highest cancer and noncancer risks based on
annual averages are limited to those pollutants failing at least one screen.
The following observations can be made from Table 7-7:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor and has
the highest cancer toxicity-weighted emissions for Washington, D.C.
• Seven of the top 10 pollutants (benzene, acetaldehyde, tetrachloroethylene, 1,3-
butadiene, naphthalene, POM as 15-PAH, and/?-dichlorobenzene) appeared on both
the highest emitted list and the highest toxicity-weighted emissions list, indicating
that most of the highest emitted pollutants were also the most toxic.
• Hexavalent chromium, the only pollutant sampled at WADC, had a low cancer risk
based its annual average (0.36 in-a-million). This is confirmed by the toxicity-
weighted emissions, which does not show hexavalent chromium among the top 10
pollutants based on toxicity-weighted emissions.
The following observations can be made from Table 7-8:
• Although toluene was the highest emitted pollutant (by mass) with a noncancer risk
factor, it did not rank in the top 10 based on toxicity-weighted emissions.
• Conversely, acrolein has the highest noncancer toxicity-weighted emissions, but did
not appear in the list of highest emitted pollutants.
• Only two pollutants (xylenes and benzene) appeared on both the top 10 emitted
pollutants and top 10 toxicity-weighted emissions lists.
• Hexavalent chromium had a low noncancer HQ based its annual average (less than
0.01). This is confirmed by the toxicity-weighted emissions, which does not show
hexavalent chromium among the top 10 pollutants based on toxicity-weighted
emissions.
7-18
-------
Washington, D.C. Pollutant Summary
WADC sampled only for hexavalent chromium. This pollutant failed one screen and did
not exceed the intermediate risk factor (no acute risk factors are available).
7-19
-------
8.0 Sites in Florida
This section presents meteorological, concentration, and spatial trends for the five
UATMP sites in and near the Tampa/St. Petersburg, FL area (AZFL, GAFL, SKFL, SMFL, and
SYFL), one site in the Ft. Lauderdale, FK area (FLFL), and one site near Orlando, FL (ORFL).
Figures 8-1 through 8-7 are topographical maps showing the monitoring sites in their urban and
rural locations. Figures 8-8 through 8-10 identify point source emission sources within 10 miles
of the sites and that reported to the 2002 NEI. In the Tampa/St. Petersburg area, three of these
sites are located in Hillsborough County and two are located in Pinellas County. SKFL and
AZFL are located on the Peninsula, with the bulk of the facilities to the north of the sites, and
closest to SKFL. GAFL is located near the Gandy Bridge on Highway 92. A cluster of facilities
is located near GAFL, but most are to the east of this site. SYFL is farther inland in Plant City.
Most of the facilities within 10 miles are to the west or east of this site. SMFL is located in the
southwest portion of Hillsborough County, with relatively few facilities nearby. A wide range of
industries have facilities near these sites, of which surface coating and fuel combustion processes
are the most numerous. FLFL (Figure 8-9) is located on Florida's east coast near Ft. Lauderdale
and nearby facilities are located mostly to the northeast and east of the monitoring site. Surface
coating and liquids distribution industries are the major source types within the 10 mile radius.
Several facilities surround ORFL (Figure 8-10), most of which are involved in waste treatment
and disposal or fuel combustion processes.
Florida's climate is subtropical, with very mild winters and warm, humid summers. The
annual average maximum temperature is around 80°F for all locations and average relative
humidity is near 70 percent. Although land and sea breezes affect each of the locations, wind
generally blows from an easterly direction due to high pressure offshore (Ruffner and Bair,
1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the GAFL and SMFL monitoring sites is Tampa International Airport (WBAN 12842); closest
3-1
-------
Figure 8-1. Tampa/St. Petersburg, Florida (AZFL) Monitoring Site
P-5t- •-,••-.•,..-•••
•j*~-4». ^=--.- —'-
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
8-2
-------
Figure 8-2. Tampa/St. Petersburg, Florida (GAFL) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
8-3
-------
Figure 8-3. Tampa/St. Petersburg, Florida (SKFL) Monitoring Site
-.- ,-:,„,. ri . i
%r *T/1
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
8-4
-------
Figure 8-4. Tampa/St. Petersburg, Florida (SMFL) Monitoring Site
&
'-•AxA ax
/X^S^
«*<****,*,„* £•
9B»rt#«W/'' /. (V '-'<-•'
•••' .-'.- . ' ' I •'' ' } ' ' —•'
"7°™?; (••/// -LJp^LJ r' i1 T ';"
'/^t-
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
8-5
-------
Figure 8-5. Tampa/St. Petersburg, Florida (SYFL) Monitoring Site
fl
-h=fei— . , at \ «
j!~**~~ri~-~-i .. "* '•».•••
I ' '"'^T^*—^ -w ,. fi«!.-:«-^.
/i >. E* - -Jm 1 • _ - •— -^^ .» * . ' '
- ;Js * • * .V1 •
:; IB -jte*. $ -^
si£**n
**'
&Z-"- ' '"
rc
>-..:/; -:^A" " _•-
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
8-6
-------
Figure 8-6. Ft. Lauderdale, Florida (FLFL) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
8-7
-------
Figure 8-7. Orlando, Florida (ORFL) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
-------
Figure 8-8. Facilities Located Within 10 Miles of the Tampa/
St. Petersburg, Florida Monitoring Sites
Legend
AZFL UATMP site
GAFL UATMP site
Nose: Due to facility density and collocation, the total facilities
displayed may not represent aH facilities within the area of intei
SKFL UATMP site
SMFL UATMP site
ffi
SYFL UATMP site
10 mile radius
I County boundary
Source Category Group (No. of Facilities)
* Automotive Repair, Services, & Parking (1)
• Business Services Facility (1}
c Chemicals & Allied Products Facility (10)
2 Electrical & Electronic Equipment Facility (5)
f Fuel Combustion Industrial Facility (27)
i Incineration Industrial Facility (6)
J Industrial Machinery & Equipment Facility (1}
= Instruments 8. Related Products Facility (2)
i Liquids Distribution Industrial Facility (11)
a Lumber & Wood Products Facility (3)
Q Medical, Dental. & Hospital Equipment and Supplies (2)
B Mineral Products Processing Industrial Facility (9)
P Miscellaneous Processes Industrial Facility (4)
• Miscellaneous Repair Services (1)
• National Security 8 International Affairs (1)
\ Non-ferrous Metals Processing Industrial Facility (2)
@ Paper & Allied Products (1)
> Pharmaceutical Production Processes Industrial Facility (1)
v Polymers & Resins Production Industrial Facility (6)
R Printing & Publishing Facility (1)
* Production of Inorganic Chemicals Industrial Facility (1)
Y Rubber & Miscellaneous Plastic Products Facility (2)
u Stone, Clay, Glass, 8 Concrete Products (2)
s Surface Coating Processes Industrial Facility (32)
-t> Transportation by Air (1)
8 Utility Boilers (4)
\PJaste Treatment S Disposal Industrial Facility (14)
' Wholesale Trade (4)
8-9
-------
Figure 8-9. Facilities Located Within 10 Miles of FLFL
. s
s s
Broward County
§.--
V
* V
-------
Figure 8-10. Facilities Located Within 10 Miles of ORFL
Semmole
County
Oiange >,
County ,
Legend
•fr ORFL UATMP site
10 mile radius
i County boundary
Source Category Group (No. of Facilities)
z Electrical & Electronic Equipment Facility (1)
D Fabricated Metal Products Facility (2)
F Fuel Combustion Industrial Facility (6)
J Industrial Machinery & Equipment Facility (1)
x Miscellaneous Manufacturing Industries (1)
v Polymers & Resins Production Industrial Facility (3)
Y Rubber 5 Miscellaneous Plastic Products Facility (2)
s Surface Coating Processes Industrial Facility (1)
T Transportation Equipment (1)
'< Waste Treatment & Disposal Industrial Facility (7)
t Unknown (2)
8-11
-------
to AZFL is St. Petersburg/Whitted Airport (WBAN 92806); closest to SKFL is St.
Petersburg/Clearwater International Airport (WBAN 12873); closest to SYFL is Winter Haven's
Gilbert Airport (WBAN 12876); closest to FLFL is Ft. Lauderdale/Hollywood International
Airport (WBAN 12849); and closest to ORFL is Orlando Executive Airport (WBAN 12841).
Table 8-1 presents average meteorological conditions of temperature (average maximum and
average), moisture (average dew point temperature, average wet-bulb temperature, and average
relative humidity), pressure (average sea level pressure), and wind information (average scalar
wind speed) for the entire year and on days samples were taken. Also included in Table 8-1 is
the 95 percent confidence interval. As shown in Table 8-1, average meteorological conditions on
sampling days were fairly representative of average weather conditions throughout the year.
8.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Florida
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contributed
to the top 95 percent of the site's total failed screens. Table 8-2 presents the pollutants that failed
at least one screen at each of the Florida monitoring sites. With exception of SYFL (which also
sampled hexavalent chromium), these sites sampled for carbonyl compounds only. Only two
carbonyls have risk screening values, acetaldehyde and formaldehyde.
The following observations are shown in Table 8-2:
• Both acetaldehyde and formaldehyde failed the screen at least once at each site, and
contributed almost equally to the number of failures. Therefore, acetaldehyde and
formaldehyde were the two pollutants of interest at each Florida site.
• While hexavalent chromium failed screens at SYFL, it contributed to less than one
percent of the total failed screens.
8-12
-------
Table 8-1. Average Meteorological Conditions near the Monitoring Sites in Florida
oo
Site
AZFL
FLFL
GAFL
ORFL
SKFL
SMFL
SYFL
WBAN
92806
12849
12842
12841
12873
12842
12876
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
81.02
±0.83
81.61
±1.76
82.88
±0.67
84.32
±1.68
81.48
±0.85
82.07
±1.81
82.50
±0.91
83.07
±1.84
82.22
±0.86
83.25
±1.77
81.48
±0.85
82.21
±1.79
82.52
±0.87
83.10
±1.75
Average
Temperature
(»F)
74.32
±0.84
75.05
±1.79
76.94
±0.72
78.08
±1.78
73.05
±0.91
74.00
±1.92
72.95
±0.92
73.88
±1.89
73.89
±0.89
74.92
±1.88
73.05
±0.91
74.02
±1.91
72.10
±0.88
72.98
±1.78
Average
Dew Point
Temperature
(OF)
63.09
± 1.00
64.05
±2.10
64.25
±0.90
65.48
±2.10
61.61
±1.11
62.90
±2.34
59.95
±1.13
61.58
±2.29
62.23
±1.07
63.62
±2.22
61.61
± 1.11
62.85
±2.30
60.57
±1.09
62.14
±2.30
Average
Wet Bulb
Temperature
(°F)
67.38
±0.83
68.17
±1.76
68.92
±0.73
69.99
±1.74
66.10
±0.92
67.14
±1.95
65.17
±0.91
66.36
±1.88
66.75
±0.89
67.87
±1.87
66.10
±0.92
67.11
±1.92
65.17
±0.89
66.36
±1.86
Average
Relative
Humidity
(%)
69.45
±0.94
70.03
±2.20
66.20
±0.84
66.62
±2.19
69.40
±0.98
70.30
±2.28
66.63
±1.02
68.29
±2.29
69.84
±2.20
70.14
±2.08
69.40
±0.98
70.17
±2.26
70.32
±1.05
71.98
±2.48
Average
Sea Level
Pressure
(mb)
1017.08
±0.39
1016.63
±0.88
1016.84
±0.35
1016.51
±0.90
1017.57
±0.39
1017.03
±0.87
1018.23
±0.42
1017.73
±.97
1017.54
±0.39
1017.09
±0.89
1017.57
±0.39
1017.07
±0.89
1017.88
±0.40
1017.29
±0.93
Average
Scalar Wind
Speed
(kt)
7.35
±0.28
7.05
±0.66
7.88
±0.32
7.55
±0.88
6.04
±0.21
6.02
±0.51
6.40
±0.24
6.34
±0.56
7.09
±0.28
6.85
±0.64
6.04
±0.21
5.98
±0.51
5.95
±0.24
6.01
±0.57
-------
Table 8-2. Comparison of Measured Concentrations and EPA Screening Values
for the Florida Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
St. Petersburg, Florida - AZFL
Acetaldehyde
Formaldehyde
Total
61
59
120
61
61
122
100.0
96.72
98.36
50.83
49.17
50.83
100.0
Davie, Florida - FLFL
Formaldehyde
Acetaldehyde
Total
47
41
88
47
41
88
100.0
100.0
100.0
53.41
46.59
53.41
100.0
Gandy in Tampa, Florida - GAFL
Acetaldehyde
Formaldehyde
Total
61
60
121
61
61
122
100.0
98.36
99.18
50.41
49.59
50.41
100.0
Winter Park, Florida - ORFL
Acetaldehyde
Formaldehyde
Total
61
58
119
61
61
122
100.0
95.08
97.54
51.26
48.74
51.26
100.0
Pinellas Park, Florida - SKFL
Acetaldehyde
Formaldehyde
Total
59
59
118
60
60
120
98.33
98.33
98.33
50.00
49.00
50.00
100.0
Simmons Park in Tampa, Florida - SMFL
Acetaldehyde
Formaldehyde
Total
61
61
122
61
61
122
100.0
100.0
100.0
50.0
50.0
50.00
100.0
Plant City, Florida - SYFL
Acetaldehyde
Formaldehyde
Hexavalent Chromium
Total
59
50
1
110
61
61
41
163
96.72
81.97
2.44
67.48
53.64
45.45
0.91
53.64
99.09
100.00
Acetaldehyde failed 100 percent of the screens at nearly all the Florida sites (one
measured detection at SKFL and two at SYFL did not fail the screen) and formaldehyde
failed 100 percent of the screens at FLFL and SMFL.
8-14
-------
8.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average concentration
of all measured detections. If there were at least seven measured detections within each season, then
a seasonal average was calculated. The seasonal average includes 1/2 MDLs substituted for all non-
detects. A seasonal average was not calculated for pollutants with less than seven measured
detections in a respective season. Finally, the annual average is the average concentration of all
measured detections and 1/2 MDLs substituted for non-detects. The resulting daily average
concentrations may therefore be inherently higher than the annual average concentrations where 1/2
MDLs replacing non-detects are incorporated into the average. Annual averages were calculated for
monitoring sites where sampling began no later than February and ended no later than November.
Daily and seasonal averages are presented in Table 8-3. With the exception of FLFL, all the Florida
monitoring sites sampled year round. Annual averages are presented and discussed in further detail
in later sections.
The following observations for acetaldehyde are shown in Table 8-3:
• Daily averages of acetaldehyde did not vary much among the sites, ranging from 1.16 ±
0.10 |ig/m3 for SYFL to 3.29 ± 1.19 |ig/m3 for FLFL.
• Seasonal acetaldehyde averages could be calculated for each season for each site.
• Most of the seasonal averages of acetaldehyde did not differ statistically. Only ORFL's
spring acetaldehyde average was significantly higher than the other seasonal averages.
The following observations for formaldehyde are shown in Table 8-3:
• The daily average concentration of formaldehyde for FLFL and GAFL were somewhat
higher than for the other sites (3.63 ± 1.22 |ig/m3 and 4.41 ± 0.76 |ig/m3, respectively),
but not statistically significant.
• With the exception of a winter average for FLFL, seasonal averages for formaldehyde
were available for each season for each site. The seasonal averages for formaldehyde for
each site show little statistical variation.
• The large confidence intervals for the spring FLFL formaldehyde average and the winter
GAFL formaldehyde average indicate that a few outliers may be influencing those
seasonal formaldehyde averages upward.
8-15
-------
Table 8-3. Daily and Seasonal Averages for the Pollutants of Interest for the Florida Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Average
(jig/m3)
Confidence
Interval
Winter
Average
(jig/m3)
Confidence
Interval
S|
Average
(jig/m3)
mng
Confidence
Interval
Summer
Average
(Hg/m3)
Confidence
Interval
Autumn
Average
(jig/m3)
Confidence
Interval
Azalea Park, St. Petersburg, Florida - AZFL
Acetaldehyde
Formaldehyde
61
61
61
61
1.96
2.46
0.21
0.23
2.15
1.78
0.47
0.33
2.08
2.49
0.43
0.43
1.57
3.07
0.17
0.30
2.01
2.53
0.44
0.53
Davie, Florida - FLFL
Acetaldehyde
Formaldehyde
47
41
47
47
3.29
3.63
1.19
1.22
4.42
NR
1.22
NR
4.93
5.05
3.34
2.61
1.52
2.19
0.18
0.20
1.98
2.53
0.44
0.36
Gandy, Tampa, Florida - GAFL
Acetaldehyde
Formaldehyde
61
61
61
61
1.66
4.41
0.22
0.76
2.44
6.26
0.41
2.52
1.54
3.47
0.34
0.65
0.84
3.67
0.11
0.36
1.76
4.12
0.37
0.63
Winter Park, Florida - ORFL
Acetaldehyde
Formaldehyde
61
61
61
61
2.40
2.49
0.29
0.23
1.92
2.06
0.28
0.41
3.39
3.09
0.91
0.39
2.13
2.91
0.28
0.43
2.19
1.95
0.25
0.31
Skyview, Florida - SKFL
Acetaldehyde
Formaldehyde
60
60
60
60
1.27
2.41
0.11
0.20
1.18
2.07
0.24
0.25
1.40
2.62
0.30
0.52
1.26
2.65
0.13
0.25
1.25
2.32
0.16
0.44
Simmons Park, Florida - SMFL
Acetaldehyde
Formaldehyde
61
61
61
61
1.35
2.56
0.13
0.23
1.36
1.86
0.26
0.31
1.37
2.75
0.27
0.56
1.30
3.05
0.17
0.31
1.39
2.61
0.29
0.37
Plant City, Florida - SYFL
Acetaldehyde
Formaldehyde
61
61
61
61
1.16
1.58
0.10
0.18
1.09
1.34
0.20
0.24
1.44
2.04
0.23
0.32
0.97
1.57
0.16
0.45
1.13
1.39
0.13
0.32
oo
NR = not reportable due to low number of measured detections.
-------
8.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for Florida monitoring sites was evaluated using
ATSDR short-term (acute) and intermediate MRL and California EPA acute REL factors. Acute
risk is defined as exposures from 1 to 14 days while intermediate risk is defined as exposures from
15 to 364 days. It is useful to compare preprocessed daily measurements to the short-term MRL and
REL factors, as well as compare seasonal averages to the intermediate MRL. No concentrations
exceeded the acute or intermediate risk value for the Florida monitoring sites.
8.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following meteorological
analyses: Pearson correlation coefficients between meteorological parameters (such as temperature)
and concentrations of the pollutants of interest; sample-year composite back trajectories; and
sample-year wind roses.
8.4.1 Pearson Correlation Analysis
Table 8-4 presents the summary of Pearson correlation coefficients for each of the pollutants
of interest and select meteorological parameters for the Florida monitoring sites. (Please refer to
Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for acetaldehyde from Table 8-4:
• Acetaldehyde exhibited negative correlations with all three moisture variables at nearly
all sites. This indicates that as moisture content increases, concentrations of acetaldehyde
tend to decrease.
• In addition, strong negative correlations were calculated between acetaldehyde and the
temperature variables for GAFL, indicating that temperature increases correlated with
decreases in acetaldehyde concentrations at this site.
• Strong positive correlations were also calculated between acetaldehyde and the sea level
pressure for AZFL and GAFL, indicating that pressure increases corresponded to
increases in acetaldehyde concentrations at these sites.
8-17
-------
Table 8-4. Pollutant of Interest Concentration Correlations with Selected Meteorological Parameters for the Florida
Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Azalea Park, St. Petersburg, Florida - AZFL
Acetaldehyde
Formaldehyde
61
61
-0.41
0.55
-0.49
0.49
-0.61
0.22
-0.58
0.32
-0.44
-0.41
0.62
0.20
-0.11
-0.06
Davie, Florida - FLFL
Acetaldehyde
Formaldehyde
47
41
-0.40
-0.38
-0.45
-0.40
-0.41
-0.32
-0.43
-0.36
-0.07
-0.01
0.07
0.02
-0.02
0.10
Gandy, Tampa, Florida - GAFL
Acetaldehyde
Formaldehyde
61
61
-0.54
0.04
-0.59
0.07
-0.61
0.11
-0.62
0.10
-0.31
0.12
0.50
0.22
0.04
-0.03
Winter Park, Florida - ORFL
Acetaldehyde
Formaldehyde
61
61
0.02
0.43
-0.06
0.29
-0.24
-0.01
-0.18
0.10
-0.37
-0.50
0.13
-0.11
-0.04
-0.18
Pinellas Park, Florida - SKFL
Acetaldehyde
Formaldehyde
60
60
-0.08
0.26
-0.19
0.17
-0.34
-0.14
-0.30
-0.04
-0.41
-0.62
0.49
0.31
-0.45
-0.16
Simmons Park, Tampa, Florida - SMFL
Acetaldehyde
Formaldehyde
61
61
0.00
0.54
-0.13
0.44
-0.34
0.14
-0.28
0.25
-0.51
-0.44
0.27
-0.06
-0.07
-0.04
Plant City, Florida - SYFL
Acetaldehyde
Formaldehyde
61
61
-0.13
0.09
-0.29
-0.05
-0.55
-0.35
-0.48
-0.25
-0.66
-0.60
0.36
0.23
-0.14
-0.12
oo
oo
-------
The following observations are gathered for formaldehyde from Table 8-4:
• Formaldehyde exhibited strong negative correlations with relative humidity at ORFL,
SKFL, and SYFL. This indicates that as moisture content increases, concentrations of
formaldehyde tended to decrease.
• Strong positive correlations were calculated between formaldehyde and maximum
temperature for AZFL and SMFL, indicating that temperature increases correlated with
increases in formaldehyde concentrations at these sites.
8.4.2 Composite Back Trajectory Analysis
Figures 8-11 through 8-17 are composite back trajectory maps for the Florida monitoring
sites for the days on which sampling occurred. Each line represents the 24-hour trajectory along
which a parcel of air traveled toward the monitoring site on a given sampling day. Each concentric
circle around the sites shown in these figures represents 100 miles.
The following observations can be made from Figures 8-11 through 8-15 and 8-17:
• The composite back trajectories at the Tampa/St. Petersburg and Orlando monitoring
sites resemble each other.
• Back trajectories originated from a variety of directions from the sites.
• The 24-hour airshed domains were moderately large, with trajectories originating nearly
600 miles away. However, 64 percent of the trajectories originated within 300 miles of
the sites and 83 percent within 400 miles from the monitoring sites.
The following observations can be made from Figures 8-16:
• The 24-hour airshed domain for FLFL was also moderately large, with trajectories
originating from nearly 600 miles away.
• The back trajectories originated from a smaller variety of directions at FLFL, less
frequently from the north or west.
• 62 percent of the trajectories originated within 300 miles of the site; and 77 percent
within 400 miles from the FLFL monitoring site.
• The FLFL monitoring site did not sample in November or December. The composite
back trajectory map might look different with addition of sampling during these months.
8-19
-------
Figure 8-11. Composite Back Trajectory Map for AZFL
oo
to
o
-------
Figure 8-12. Composite Back Trajectory Map for GAFL
oo
to
-------
Figure 8-13. Composite Back Trajectory Map for SKFL
oo
to
to
-------
Figure 8-14. Composite Back Trajectory Map for SMFL
oo
to
-------
Figure 8-15. Composite Back Trajectory Map for SYFL
oo
to
-------
Figure 8-16. Composite Back Trajectory Map for FLFL
oo
to
-------
Figure 8-17. Composite Back Trajectory Map for ORFL
oo
to
-------
8.4.3 Wind Rose Analysis
Hourly wind data from weather stations at Tampa International, Whitted, St.
Petersburg/Clearwater International, Gilbert, Orland Executive, and Ft. Lauderdale/Hollywood
International Airports were uploaded into a wind rose software program WRPLOT (Lakes, 2006).
WRPLOT produces a graphical wind rose from the wind data. A wind rose shows the frequency of
wind directions about a 16-point compass, and uses different shading to represent wind speeds.
Figures 8-18 thru 8-24 are wind roses for the Florida monitoring sites on days samples were taken.
Observations from Figure 8-18 for AZFL include:
• Hourly winds near AZFL varied greatly, but originated more frequently out of the east (9
percent of observations), and north (8 percent of observations).
• Wind speeds ranged from 7 to 11 knots on days that samples were taken (38 percent of
observations).
• Calm winds (<2 knots) were observed for 7 percent of observations.
Observations from Figure 8-19 for GAFL include:
• Hourly winds near GAFL were predominantly out of the west (9 percent of observations)
and east, east-northeast and west-southwest (each 7 percent) on sampling days.
• Wind speeds ranged from 7 to 11 knots on days that samples were taken (39 percent of
observations), with calm winds observed for 12 percent of measurements.
Observations from Figure 8-20 for SKFL include:
• Hourly winds near SKFL were predominantly out of the east, east-northeast, or west
(each accounting for approximately 8 percent of observations) on sampling days.
• Wind speeds ranged from 7 to 11 knots on days that samples were taken. However,
winds from the south had the highest frequency of winds greater than 11 knots.
• Calm winds were observed for 9 percent of observations.
Observations from Figure 8-21 for SMFL include:
• Similar to GAFL, hourly winds near SMFL were predominantly out of the west (10
percent of observations), east (7 percent), and east-northeast (7 percent on sampling
8-27
-------
Figure 8-18. Wind Rose for AZFL Sampling Days
•NORTH"-*
oo
to
oo
10%
SOUTH--'
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
•J 2- 4
Calms: 6.6S%
-------
Figure 8-19. Wind Rose for GAFL Sampling Days
TNORTH"--
oo
to
VO
10%
SOUTH--'
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
•J 2- 4
Calms: 12.15%
-------
Figure 8-20. Wind Rose for SKFL Sampling Days
TNORTH"--
oo
OJ
o
10%
SOUTH--'
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
•J 2- 4
Calms:
-------
Figure 8-21. Wind Rose for SMFL Sampling Days
TNORTH"--
oo
10%
SOUTH--'
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
•J 2- 4
Calms: 12.43%
-------
Figure 8-22. Wind Rose for SYFL Sampling Days
TNORTH"--
oo
OJ
to
10%
SOUTH--'
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
•J 2- 4
Calms: 15.95%
-------
Figure 8-23. Wind Rose for FLFL Sampling Days
oo
WEST
'NORTH"-*
20%
16%
12%
SOUTH.-"
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
•J 2- 4
Calms: 12.61%
-------
Figure 8-24. Wind Rose for ORFL Sampling Days
oo
10%
SOUTH,-*
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
^| 11 • 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 13.73%
-------
days). Both of these sites are located in close proximity to Tampa Bay, which lies to the
west of the monitoring locations.
• Wind speeds ranged from 7 to 11 knots on days that samples were taken (39 percent of
observations). Calm winds were observed for 12 percent of observations.
Observations from Figure 8-22 for SYFL include:
• Hourly winds near SYFL were predominantly out of the east (10 percent of
observations), with north, east-northeast, and southerly winds each making up another 6
percent of observations on sampling days.
• Wind speeds ranged from 7 to 11 knots on most days that samples were taken.
• Calm winds were observed for 16 percent of observations.
Each of the previous five sites reside in the Tampa/St. Petersburg area on Florida's Gulf Coast.
While there are differences, their wind roses were similar to each other. In contrast, the FLFL site is
the only Florida site residing on Florida's Atlantic Coast, and its wind rose was much different than
the other sites. Observations from Figure 8-23 for FLFL include:
• Hourly winds near FLFL were predominantly out of the east (15 percent of observations),
east-southeast (14 percent) and southeast (11 percent) on sampling days.
• Wind speeds ranged from 7 to 11 knots on days that samples were taken, although winds
out of the east were recorded at higher speeds more frequently than other directions.
• Calm winds were recorded for 13 percent of observations.
Observations from Figure 8-24 for ORFL include:
• Hourly winds near ORFL were predominantly out of the south (8 percent of
observations), with the east, north, and west each making up 7 percent of observations on
sampling days.
• Wind speeds ranged from 7 to 11 knots on days that samples were taken.
• Calm winds were recorded for 14 percent of observations.
8.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could not
8-35
-------
be performed as ERG did not analyze VOCs for this site. A mobile tracer analysis could not be
performed as these sites did not sample for SNMOC.
8.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Pinellas, Hillsborough, Orange, and Broward
Counties in Florida were obtained from the Florida Department of Highway Safety and Motor
Vehicles and the U.S. Census Bureau, and are summarized in Table 8-5. Table 8-5 also includes a
vehicle registration to county population ratio (vehicles per person). In addition, the population
within 10 miles of each site is presented. An estimation of 10-mile vehicle registration was
computed using the 10-mile population surrounding the monitor and the vehicle registration ratio.
Finally, Table 8-5 contains the average daily traffic information, which represents the average
number of vehicles passing the monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 8-5 include:
• Of the four Florida counties with monitoring sites, Broward County, where FLFL is
located, is the most populous, while Pinellas County, where AZFL and SKFL are located,
are the least populated.
• Broward County has the lowest estimated vehicles per person and Pinellas County has
the highest.
• While FLFL has the highest number of people living within a 10 mile radius of the site,
SMFL has the least. SMFL is located within a wildlife sanctuary at E.G. Simmons Park.
• The GAFL monitoring site, located near the Gandy Bridge between Tampa and St.
Petersburg, experiences the highest daily traffic volume, while SYFL, located in the more
rural outskirts of the Tampa area, experiences the lowest.
8.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the 2006
program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was conducted.
8-36
-------
Table 8-5. Motor Vehicle Information for the Florida Monitoring Sites
Site
AZFL
FLFL
GAFL
ORFL
SKFL
SMFL
SYFL
2006 Estimated
County Population
924,413
1,787,636
1,157,738
1,043,500
924,413
1,157,738
1,157,738
Number of
Vehicles
Registered
,461,506
,637,132
,189,885
,043,571
,461,505
,189,885
,189,885
Vehicles per Person
(Registration:
Population)
1.58
0.91
1.03
1.00
1.58
1.03
1.03
Population
Within 10 Miles
574,226
1,333,555
437,022
993,441
699,265
61,186
124,967
Estimated
10 Mile Vehicle
Ownership
907,856
1,221,281
486,156
993,509
1,105,544
62,885
128,437
Traffic Data
(Daily
Average)
51,000
8,000
81,400
59,000
50,500
18,700
5,142
oo
-------
Details on how this analysis was conducted can be found in Section 3.3.4. The Florida sites with
enough data for a trends analysis are AZFL, GAFL, ORFL, SKFL and SYFL. Figures 8-25 through
8-29 present the trends analysis for formaldehyde for these sites.
The following observations can be made from Figures 8-25 through 8-29:
• After a three year downward trend, concentrations of formaldehyde at the AZFL site have
generally been increasing slightly over the last three years.
• While concentrations of formaldehyde at the GAFL site appear to have increased
significantly from 2004 to 2005, the confidence interval for the 2005 formaldehyde
average indicates that the average was influenced by outliers. The 2006 formaldehyde
average concentration is much closer to those from previous years. However, the 2006
average concentration is an increase from the 2003 and 2004 averages.
• The formaldehyde average at the ORFL monitoring site has decreased slightly since
holding steady in 2005.
• Although the formaldehyde average at the SKFL monitoring site appears to have
decreased each year, the very large confidence intervals in 2004 and 2005 make it
difficult to make an accurate assessment.
• The 2006 formaldehyde average at SYFL appears to have decreased from 2005 levels.
However, given the confidence level shown for 2005, it is difficult to discern if this is an
actual decreasing trend.
8.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at each
Florida site and where the annual average concentrations could be calculated (refer to Section 3.3.5
regarding the definition of an annual average). Annual averages, theoretical cancer and noncancer
risk, cancer UREs and/or noncancer RfCs are presented in Table 8-6. The NATA data is presented
for the census tract where the monitoring site is located. Additionally, the pollutants of interest are
bolded.
The following observations can be made from Table 8-6:
• Formaldehyde had higher daily averages than acetaldehyde at each Florida site, which
was also true for the annual averages.
8-38
-------
Figure 8-25. Comparison of Yearly Averages for the AZFL Monitoring Site
4.5
oo
VO
£
0.
0
13 2.£
0)
o
§ 2
O
0)
O)
(0
5 1.5
0.5
f
i
2001
2002
2003 2004
Year
2005
2006
D Formaldehyde
-------
16
14
12
.a
a.
— 10
c
O
a>
o
o
O
a>
0)
Figure 8-26. Comparison of Yearly Averages for the GAFL Monitoring Site
oo
•*•
¥
2001
2002
2003
2004
2005
2006
Year
D Formaldehyde
-------
3.5
3
~ 2.5
.a
a.
Figure 8-27. Comparison of Yearly Averages for the ORFL Monitoring Site
O)
2
0)
0.5
2003
2004
2005
2006
Year
D Formaldehyde
-------
Figure 8-28. Comparison of Yearly Averages for the SKFL Monitoring Site
.a
a.
f 5
o
+J
2
4-1
S 4
o
c
o
o
-------
Figure 8-29. Comparison of Yearly Averages for the SYFL Monitoring Site
oo
2.5
a. 2
_o.
o
?
S 1.5
o
o
o
-------
• For each site, acetaldehyde had a higher cancer risk than formaldehyde, ranging from
2.55 in-a-million for SYFL to 5.28 in-a-million for ORFL.
• Cancer risk due to formaldehyde was less than 0.05 in-a-million for all of the Florida
sites.
• Noncancer HQs were less than 0.5 for the pollutants that failed screens at the Florida
sites.
• Annual averages could not be calculated at FLFL because the site stopped sampling
in October.
In addition to the annual averages and risks based on 2006 monitoring data, data from
EPA's 1999 NATA were retrieved and are also presented in Table 8-6. Data from NATA is
presented by the census tract where each site resides.
The census tract information for the Florida sites follows, grouped by county:
• 12103022402 for AZFL and!2103024905 for SKFL; the 5,456 people residing in the
AZFL census tract represent 0.6 percent of the 2000 Pinellas County population,
while the 6,522 residents of the SKFL census tract represent 0.7 percent of the 2000
Pinellas County population.
• 12011070204 for FLFL; the 4,301 residents of the FLFL census tract represent 0.3
percent of the 2000 Broward County population.
• 12057006500 for GAFL, 12057012204 for SYFL, and 12057014107 for SMFL; the
5,913 people residing in the GAFL census tract represent 0.6 percent of the 2000
Hillsborough County population; the 4,362 residents of the SYFL census tract
represent 0.4 percent of the 2000 Hillsborough County population; and the 1,803
residents of the more rural SMFL census tract represent just less than 0.2 percent of
the Hillsborough County population.
• 12095015901 for ORFL; the 2,083 people residing in the ORFL census tract
represent 0.2 percent of the 2000 Orange County population.
The following observation can be made from the NATA data in Table 8-6:
• NATA-modeled concentrations for formaldehyde and acetaldehyde were very similar
to those measured in 2006.
• NATA-modeled cancer and noncancer risks for formaldehyde and acetaldehyde were
very similar to those calculated from the annual averages.
8-44
-------
Table 8-6. Chronic Risk Summary for the Monitoring Sites in Florida
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Ug/m3)
Cancer
Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer
Risk
(in-a-
million)
Noncancer
Risk (HQ)
Azalea Park, St. Petersburg (AZFL) - Census Tract ID 12103022402
Acetaldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
1.21
1.31
2.67
0.01
0.13
0.13
1.96 ±0.21
2.46 ±0.23
4.31
0.01
0.22
0.25
Davie, Florida (FLFL) - Census Tract ID 12011070204
Acetaldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
1.68
2.30
3.71
0.01
0.19
0.23
3.29 ±1.19
3.17±1.12
NA
NA
NA
NA
Gandy, Tampa, Florida (GAFL) - Census Tract ID 12057006500
Acetaldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
1.73
1.72
3.81
0.01
0.19
0.18
1.66 ±0.22
4.41 ±0.76
3.64
0.02
0.18
0.45
Winter Park, Florida (ORFL) - Census Tract ID 12095015901
Acetaldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
1.99
1.98
4.38
0.01
0.22
0.20
2.40 ±0.29
2.49 ±0.23
5.28
0.01
0.27
0.25
Skyview, Florida (SKFL) - Census Tract ID 12103024905
Acetaldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
Simmons Park, Tani|
Acetaldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
1.65
1.73
3.63
0.01
0.18
0.18
1.27±0.11
2.41 ±0.20
2.79
0.01
0.14
0.25
)a, Florida (SMFL) - Census Tract ID 12057014107
1.06
1.26
2.33
0.01
0.12
0.13
1.35±0.13
2.56 ±0.23
2.97
0.01
0.15
0.26
Plant City, Florida (SYFL) - Census Tract ID 12057012204
Acetaldehyde
Formaldehyde
Hexavalent Chromium
0.0000022
5.5E-09
0.012
0.009
0.0098
0.0001
1.25
1.42
<0.01
2.75
0.01
1.00
0.14
0.14
O.01
1.16±0.10
1.58 ±0.18
<0.01±<0.01
2.55
0.01
0.22
0.13
0.16
O.01
oo
NA = Not available due to short sampling duration.
BOLD = pollutant of interest.
-------
8.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 8-7 and 8-8 present a risk-
based assessment of the county-level emissions based on cancer and noncancer toxicity,
respectively. Table 8-7 presents the 10 pollutants with the highest emissions from the 2002 NEI,
the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with the
highest cancer risk (in-a-million) as calculated from the annual average. Table 8-8 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer table, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer and noncancer risk based on each site's annual average is limited to those pollutants for
which each respective site sampled. In addition, the highest cancer and noncancer risks based on
annual averages are limited to those pollutants failing at least one screen.
The following observations can be made for FLFL in Broward County from Table 8-7:
• Like many other counties with UATMP sites, benzene was the highest emitted
pollutant (by mass) with a cancer risk factor in Broward County, where FLFL is
located.
• Unlike most counties, naphthalene had the highest cancer toxicity-weighted
emissions.
• Benzene did have the second highest cancer toxicity-weighted emissions, while
naphthalene had the second highest total emissions.
• Formaldehyde and acetaldehyde were the only pollutants with failed screens at FLFL,
but annual averages (and therefore, cancer risks) could not be calculated.
• These two pollutants had the fourth and fifth highest total emissions according to the
NEI, but neither pollutant appeared in the list of 10 highest cancer toxicity-weighted
emissions.
8-46
-------
Table 8-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Florida Monitoring Sites
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on
Annual Average Concentration
(Site-Specific)
Cancer Risk
Pollutant (in-a-million)
Davie, Florida (FLFL) - Broward County
Benzene
Naphthalene
Dichloromethane
Formaldehyde
Acetaldehyde
1,3 -Butadiene
1 , 3 -Dichloropropene
Tetrachloroethylene
£>-Dichlorobenzene
Trichloroethylene
1,357.39
823.24
530.09
523.41
192.21
159.40
116.00
92.71
59.42
34.84
Naphthalene
Benzene
1,3 -Butadiene
Lead
Nickel
Arsenic
£>-Dichlorobenzene
Tetrachloroethylene
1 , 3 -Dichloropropene
Polycyclic Organic Matter as 7-PAH
2.80E-02
1.06E-02
4.78E-03
4.46E-03
1.83E-03
9.06E-04
6.54E-04
5.47E-04
4.64E-04
4.52E-04
Gandy, Tampa, Florida (GAFL) - Hillsborough County
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
Dichloromethane
Naphthalene
Trichloroethylene
Poly cyclic Organic Matter as 15 -PAH
Lead
1,078.20
441.37
168.60
116.37
58.96
32.75
31.70
21.19
5.29
3.60
Benzene
1,3 -Butadiene
Lead
Hexavalent Chromium
Naphthalene
Cadmium
Nickel
Arsenic
Acetaldehyde
Tetrachloroethylene
8.41E-03
3.49E-03
1.60E-03
1.22E-03
1.08E-03
7.24E-04
4.08E-04
3.90E-04
3.71E-04
3.48E-04
Acetaldehyde 3.64
Formaldehyde 0.02
oo
-------
Table 8-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Florida Monitoring Sites (Continued)
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Cancer Risk
Pollutant (in-a-million)
Simmons Park, Tampa, Florida (SMFL) - Hillsborough County
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
Dichloromethane
Naphthalene
Trichloroethylene
Poly cyclic Organic Matter as 15 -PAH
Lead
1,078.20
441.37
168.60
116.37
58.96
32.75
31.70
21.19
5.29
3.60
Benzene
1,3 -Butadiene
Lead
Hexavalent Chromium
Naphthalene
Cadmium
Nickel
Arsenic
Acetaldehyde
Tetrachloroethylene
8.41E-03
3.49E-03
1.60E-03
1.22E-03
1.08E-03
7.24E-04
4.08E-04
3.90E-04
3.71E-04
3.48E-04
Acetaldehyde 2.97
Formaldehyde 0.01
Plant City, Florida (SYFL) - Hillsborough County
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
Dichloromethane
Naphthalene
Trichloroethylene
Poly cyclic Organic Matter as 15 -PAH
Lead
1,078.20
441.37
168.60
116.37
58.96
32.75
31.70
21.19
5.29
3.60
Benzene
1,3 -Butadiene
Lead
Hexavalent Chromium
Naphthalene
Cadmium
Nickel
Arsenic
Acetaldehyde
Tetrachloroethylene
8.41E-03
3.49E-03
1.60E-03
1.22E-03
1.08E-03
7.24E-04
4.08E-04
3.90E-04
3.71E-04
3.48E-04
Acetaldehyde 2.55
Hexavalent Chromium 0.22
Formaldehyde 0.01
oo
-k
oo
-------
Table 8-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Florida Monitoring Sites (Continued)
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Cancer Risk
Pollutant (in-a-million)
Winter Park, Florida (ORFL) - Orange County
Benzene
Formaldehyde
Dichloromethane
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
Naphthalene
Trichloroethylene
Poly cyclic Organic Matter as 15 -PAH
Polycyclic Organic Matter as 7-PAH
1,068.60
379.84
157.31
134.32
122.78
61.88
28.42
24.25
4.89
1.22
Benzene
1,3 -Butadiene
Arsenic
Lead
Naphthalene
Tetrachloroethylene
Acetaldehyde
Polycyclic Organic Matter as 15-PAH
Polycyclic Organic Matter as 7-PAH
Hexavalent Chromium
8.34E-03
3.68E-03
2.14E-03
1.47E-03
9.66E-04
3.65E-04
2.96E-04
2.69E-04
2.61E-04
2.50E-04
Acetaldehyde 5.28
Formaldehyde 0.01
Azalea Park, St. Petersburg, Florida (AZFL) - Pinellas County
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Naphthalene
Trichloroethylene
Nickel
Tetrachloroethylene
Polycyclic Organic Matter as 15 -PAH
886.09
299.22
107.60
100.78
64.63
22.64
20.71
14.50
10.28
3.14
Benzene
1,3 -Butadiene
Nickel
Lead
Arsenic
Naphthalene
Hexavalent Chromium
Acetaldehyde
Polycyclic Organic Matter as 7-PAH
Polycyclic Organic Matter as 15-PAH
6.91E-03
3.02E-03
2.32E-03
2.12E-03
8.22E-04
7.70E-04
3.28E-04
2.37E-04
2.17E-04
1.73E-04
Acetaldehyde 4.31
Formaldehyde 0.01
oo
-k
VO
-------
Table 8-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Florida Monitoring Sites (Continued)
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Cancer Risk
Pollutant (in-a-million)
Pinellas Park, Florida (SKFL) - Pinellas County
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Naphthalene
Trichloroethylene
Nickel
Tetrachloroethylene
Poly cyclic Organic Matter as 15 -PAH
886.09
299.22
107.60
100.78
64.63
22.64
20.71
14.50
10.28
3.14
Benzene
1,3 -Butadiene
Nickel
Lead
Arsenic
Naphthalene
Hexavalent Chromium
Acetaldehyde
Polycyclic Organic Matter as 7-PAH
Poly cyclic Organic Matter as 15 -PAH
6.91E-03
3.02E-03
2.32E-03
2.12E-03
8.22E-04
7.70E-04
3.28E-04
2.37E-04
2.17E-04
1.73E-04
Acetaldehyde 2.79
Formaldehyde 0.01
oo
I
o
-------
Table 8-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Florida Monitoring Sites
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Noncancer Risk
Pollutant (HQ)
Davie, Florida (FLFL) - Broward County
Xylenes
Toluene
Ethylbenzene
Chloroform
Methanol
Benzene
Naphthalene
Hexane
Dichloromethane
Formaldehyde
56,151.18
31,886.49
13,718.43
9,751.74
7,845.13
1,357.39
823.24
647.07
530.09
523.41
Acrolein
Xylenes
Naphthalene
Nickel
Chloroform
Toluene
1,3 -Butadiene
Formaldehyde
Benzene
Bromomethane
1,583,912.55
561,511.76
274,414.51
176,214.27
99,507.59
79,716.21
79,700.70
53,409.33
45,246.30
32,400.00
Gandy, Tampa, Florida (GAFL) - Hillsborough County
Hydrochloric Acid
Toluene
Xylenes
Methanol
Benzene
Hexane
Ethylbenzene
Formaldehyde
Hydrogen Fluoride
Methyl Isobutyl Ketone
3,106.48
2,859.57
2,002.05
1,171.89
1,078.20
554.19
466.12
441.37
403.65
367.10
Acrolein
Hydrochloric Acid
1,3 -Butadiene
Formaldehyde
Manganese
Nickel
Benzene
Cadmium
Xylenes
Acetaldehyde
1,259,274.30
155,323.87
58,187.34
45,037.84
44,152.15
39,275.93
35,939.93
20,105.24
20,020.54
18,733.64
Formaldehyde 0.45
Acetaldehyde 0.18
oo
-------
Table 8-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Florida Monitoring Sites (Continued)
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on Annual
Average Concentrations
(Site-Specific)
Noncancer Risk
Pollutant (HQ)
Simmons Park, Tampa, Florida (SMFL) - Hillsborough County
Hydrochloric Acid
Toluene
Xylenes
Methanol
Benzene
Hexane
Ethylbenzene
Formaldehyde
Hydrogen Fluoride
Methyl Isobutyl Ketone
3,106.48
2,859.57
2,002.05
1,171.89
1,078.20
554.19
466.12
441.37
403.65
367.10
Acrolein
Hydrochloric Acid
1,3 -Butadiene
Formaldehyde
Manganese
Nickel
Benzene
Cadmium
Xylenes
Acetaldehyde
1,259,274.30
155,323.87
58,187.34
45,037.84
44,152.15
39,275.93
35,939.93
20,105.24
20,020.54
18,733.64
Formaldehyde 0.26
Acetaldehyde 0.15
Plant City, Florida (SYFL) - Hillsborough County
Hydrochloric Acid
Toluene
Xylenes
Methanol
Benzene
Hexane
Ethylbenzene
Formaldehyde
Hydrogen Fluoride
Methyl Isobutyl Ketone
3,106.48
2,859.57
2,002.05
1,171.89
1,078.20
554.19
466.12
441.37
403.65
367.10
Acrolein
Hydrochloric Acid
1,3 -Butadiene
Formaldehyde
Manganese
Nickel
Benzene
Cadmium
Xylenes
Acetaldehyde
1,259,274.30
155,323.87
58,187.34
45,037.84
44,152.15
39,275.93
35,939.93
20,105.24
20,020.54
18,733.64
Formaldehyde 0.16
Acetaldehyde 0.13
Hexavalent Chromium 0.00
oo
I
to
-------
Table 8-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Florida Monitoring Sites (Continued)
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Noncancer Risk
Pollutant (HQ)
Winter Park, Florida (ORFL) - Orange County
Toluene
Xylenes
Hydrochloric Acid
Benzene
Methanol
Hexane
Ethylbenzene
Formaldehyde
Methyl Isobutyl Ketone
Methyl Ethyl Ketone
2,883.18
1,958.88
1,434.28
1,068.60
979.23
511.76
471.37
379.84
340.63
264.60
Acrolein
Hydrochloric Acid
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Arsenic
Acetaldehyde
Cyanide
Nickel
1,129,242.73
71,713.76
61,391.20
38,758.87
35,619.97
19,588.83
16,603.66
14,924.42
12,315.62
10,037.02
Acetaldehyde 0.27
Formaldehyde 0.25
Azalea Park, St. Petersburg, Florida (AZFL) - Pinellas County
Toluene
Xylenes
Methanol
Benzene
Hexane
Hydrochloric Acid
Ethylbenzene
Formaldehyde
Styrene
Methyl 7er/-Butyl Ether
2,450.18
1,614.36
1,169.66
886.09
451.60
435.32
410.00
299.22
295.25
185.76
Acrolein
Nickel
1,3 -Butadiene
Formaldehyde
Benzene
Manganese
Hydrochloric Acid
Xylenes
Acetaldehyde
Naphthalene
725,871.26
223,056.24
50,388.30
30,533.10
29,536.39
22,160.13
21,766.06
16,143.60
11,955.94
7,547.45
Formaldehyde 0.25
Acetaldehyde 0.22
oo
-------
Table 8-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Florida Monitoring Sites (Continued)
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Noncancer Risk
Pollutant (HQ)
Pinellas Park, Florida (SKFL) - Pinellas County
Toluene
Xylenes
Methanol
Benzene
Hexane
Hydrochloric Acid
Ethylbenzene
Formaldehyde
Styrene
Methyl Tert-Butyl Ether
2,450.18
1,614.36
1,169.66
886.09
451.60
435.32
410.00
299.22
295.25
185.76
Acrolein
Nickel
1,3 -Butadiene
Formaldehyde
Benzene
Manganese
Hydrochloric Acid
Xylenes
Acetaldehyde
Naphthalene
725,871.26
223,056.24
50,388.30
30,533.10
29,536.39
22,160.13
21,766.06
16,143.60
11,955.94
7,547.45
Formaldehyde 0.25
Acetaldehyde 0.14
oo
-------
The following observations can be made for GAFL, SMFL, and SYFL in Hillsborough
County from Table 8-7:
• Benzene was the highest emitted pollutant with a cancer risk factor and had the
highest cancer toxicity-weighted emissions for Hillsborough County.
• Five other pollutants (acetaldehyde, 1,3-butadiene, tetrachloroethylene, naphthalene,
and lead) appeared on both the highest emissions and highest cancer toxicity-
weighted emissions lists.
• Only acetaldehyde, which had the highest cancer risks of the pollutants of interest at
GAFL, SMFL, and SYFL, appeared on all three lists.
• SYFL also measured hexavalent chromium during the 2006 UATMP. Hexavalent
chromium was the pollutant with the fourth highest toxicity-weighted emissions in
Hillsborough County.
The following observations can be made for ORFL in Orange County from Table 8-7:
• Benzene was the highest emitted pollutant with a cancer risk factor and had the
highest cancer toxicity-weighted emissions for Orange County.
• Formaldehyde and acetaldehyde had the second and fourth highest emissions in
Orange County, respectively.
• Acetaldehyde ranked 7th in highest toxicity-weighted emissions while formaldehyde
did not make the list.
The following observations can be made for AZFL and SKFL in Pinellas County from
Table 8-7:
• Benzene was also the highest emitted pollutant and had the highest cancer toxicity-
weighted emissions for Pinellas County.
• Formaldehyde and acetaldehyde had the second and third highest emissions in
Pinellas County, respectively.
• Similar to Orange County, acetaldehyde ranked 8th in highest toxicity-weighted
emissions while formaldehyde did not make the list.
The following observations can be made for FLFL in Broward County from Table 8-8:
• Total xylenes were the highest emitted pollutant (by mass) with a noncancer risk
factor in Broward County, but had the second highest toxicity-weighted emissions.
8-55
-------
• Acrolein, which did not appear on the list of 10 highest emitted pollutants, had the
highest toxicity-weighted emissions.
• In addition to xylenes, five other pollutants (toluene, chloroform, benzene,
naphthalene, and formaldehyde) appeared in both "top 10" lists.
The following observations can be made for GAFL, SMFL, and SYFL in Hillsborough
County from Table 8-8:
• Hydrochloric acid was the highest emitted pollutant with a noncancer risk factor in
Hillsborough County, it had the second highest toxicity-weighted emissions.
• Similar to Broward County, acrolein had the highest toxicity-weighted emissions, but
did not appear on the list often highest emitted pollutants.
• Only formaldehyde appeared on all three top 10 lists.
• While acetaldehyde was not one of the highest emitted pollutants in Hillsborough
County, it ranked 10th for highest noncancer toxicity-weighted emissions.
• Noncancer HQs for acetaldehyde and formaldehyde were all less than 0.50.
The following observations can be made for ORFL in Orange County and for AZFL and
SKFL in Pinellas County from Table 8-8:
• Although toluene was the highest emitted pollutant, acrolein had the highest
noncancer toxicity-weighted emissions.
• Similar to the other Florida counties, acrolein was not one of the 10 highest emitted
pollutants.
• Again, only formaldehyde appeared on all three top 10 lists.
• While acetaldehyde was not one of the highest emitted pollutants in either Orange or
Pinellas Counties, it ranked 8
toxicity-weighted emissions.
Pinellas Counties, it ranked 8th and 9th, respectively, for the highest noncancer
Noncancer HQs for acetaldehyde and formaldehyde were all less than 0.30 for ORFL,
AZFL, and SKFL.
8-56
-------
Florida Pollutant Summary
• The pollutants of interest at all seven Florida sites were acetaldehyde and formaldehyde.
• The pollutant of interest with the highest daily average at all the monitoring sites was
formaldehyde.
• Acetaldehyde failed 100 percent of the screens at nearly all the Florida sites (one
measured detection at SKFL and two at SYFL did not fail. Formaldehyde failed 100
percent of the screens at FLFL and SMFL.
• A comparison of formaldehyde average concentrations for all years ofUATMP
participation showed that 2006 formaldehyde concentrations increased slightly atAZFL
and decreased slightly at ORFL. Due to the presence of outliers, the appearance of a
trend cannot be determined for GAFL, SKFL, and SYFL.
8-57
-------
9.0 Site in Georgia
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Georgia (SDGA). This site is located in the Atlanta-Sandy Springs-Marietta MSA.
Figure 9-1 is a topographical map showing the monitoring site in its urban location. Figure 9-2
identifies point source emission locations within 10 miles of this site that reported to the 2002
NEI for point sources. SDGA is located near a number of point sources, most of which are
located to the west of the site. These sources represent a wide variety of industries, including
fuel combustion and waste treatment and disposal processes.
Atlanta is the largest city in Georgia, and is located at the base of the Blue Ridge
Mountains. The Gulf of Mexico to the south is the major moisture source for weather systems
that move across the region. Both topographical features, in addition to the Atlantic Ocean to the
east, exert moderating influences on the area's climate (Ruffner and Bair, 1987).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the SDGA monitoring site is at WB Hartsfield/Atlanta International Airport (WBAN 13874).
Table 9-1 presents the average meteorological conditions of temperature (average maximum and
average), moisture (average dew point temperature, average wet-bulb temperature, and average
relative humidity), pressure (average sea level pressure), and wind information (average scalar
wind speed) for the entire year and on days samples were collected. Also included in Table 9-1
is the 95 percent confidence interval. As shown in Table 9-1, average meteorological conditions
on sampling days were fairly representative of average weather conditions throughout the year.
9.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Georgia
monitoring site. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
9-1
-------
Figure 9-1. Decatur, Georgia (SDGA) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
9-2
-------
Figure 9-2. Facilities Located Within 10 Miles of SDGA
CY
Fulton
County
Dekalb
County
; Rockdale /
, County /
Clayton
County
Henry
County
Note: Due to fadlrty density and collocation, the total facilities
displayed may not represent ali facilities within the area of interest.
Legend
••&• SDGAUATMPstte
10 mite radius
Source Category Group (No. of Facilities)
* Automotive Repair. Services, & Parking (1)
c Chemicals & Allied Products Facility (5)
2 Electrical & Electronic Equipment Facility (1)
F Fuel Combustion Industrial Facility (7)
s, Lumber & Wood Products Facility (1}
B Mineral Products Processing Industrial Facility (1)
P Miscellaneous Processes Industrial Facility (5)
County boundary
@ Paper & Allied Products (1)
v Polymers & Resins Production Industrial Facility (1)
Q Primary Metal Industries Facility (1)
4 Production of Organic Chemicals Industrial Facility {1)
Y Rubber & Miscellaneous Plastic Products Facility (2)
s Surface Coating Processes Industrial Facility (1)
i Waste Treatment & Disposal Industrial Facility (7)
9-3
-------
Table 9-1. Average Meteorological Conditions near the Monitoring Site in Georgia
Site
SDGA
WBAN
13874
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
72.41
±1.45
73.48
±3.28
Average
Temperature
(»F)
63.16
±1.42
64.13
±3.12
Average
Dew Point
Temperature
(°F)
49.14
±1.57
50.80
±3.23
Average
Wet Bulb
Temperature
(°F)
55.65
±1.31
56.76
±2.78
Average
Relative
Humidity
(%)
63.43
±1.36
65.03
±3.28
Average
Sea Level
Pressure
(mb)
1017.66
±0.55
1016.88
±1.22
Average
Scalar Wind
Speed
(kt)
7.10
±0.27
7.29
±0.68
VO
-------
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. Table 9-2 presents the pollutants that failed
at least one screen at SDGA. At SDGA, only hexavalent chromium was sampled.
The following observations are shown in Table 9-2:
• Five of 52 hexavalent chromium concentrations failed screens. This is less than 10
percent of all measured detections.
Table 9-2. Comparison of Measured Concentrations and EPA Screening Values for
the Georgia Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
Cumulative
% of Total %
Failures Contribution
Decatur, Georgia - SDGA
Hexavalent Chromium
5
52
9.52
9.52 100
9.2 Concentration Averages
Three types of concentration averages were calculated for hexavalent chromium: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 9-3. Annual averages are presented and discussed in further detail in later
sections.
9-5
-------
Table 9-3. Daily and Seasonal Averages for Pollutants of Interest for the Georgia Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
Decatur, Georgia - SDGA
Hexavalent Chromium
52
57
0.05
0.01
0.03
0.01
0.05
0.02
0.06
0.01
0.05
0.04
VO
-------
The following observations are shown in Table 9-3:
• The daily average of hexavalent chromium at SDGA was 0.05 ± 0.01 ng/m3.
• The highest seasonal average occurred in summer (0.06 ± 0.01 ng/m3). However, the
seasonal averages varied little, with winter exhibiting the lowest seasonal average
(0.03 ± 0.01 ng/m3).
9.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for SDGA was evaluated using ATSDR acute
and intermediate MRL and California EPA acute REL factors. Acute risk is defined as
exposures from 1 to 14 days while intermediate risk is defined as exposures from 15 to 364 days.
Its is useful to compare the preprocessed daily measurement to the short-term MRL and REL
factors, as well as compare the seasonal averages to the intermediate MRL. Hexavalent
chromium has no acute risk factors; therefore, acute risk could not be evaluated. The
intermediate risk value was not exceeded at SDGA.
9.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
9.4.1 Pearson Correlation Analysis
Table 9-4 presents the summary of Pearson correlation coefficients for hexavalent
chromium and select meteorological parameters at the SDGA monitoring site. (Please refer to
Section 3.1.6 for more information on Pearson correlations.) Correlations calculated for SDGA
between hexavalent chromium and the meteorological parameters were weak.
9.4.2 Composite Back Trajectory Analysis
Figure 9-3 is a composite back trajectory map for the SDGA monitoring site for the days
on which sampling occurred. Each line represents the 24-hour trajectory along which a parcel of
9-7
-------
VO
oo
Table 9-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Georgia
Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Decatur, Georgia - SDGA
Hexavalent Chromium
52
0.19
0.18
0.13
0.16
-0.08
0.10
-0.30
-------
Figure 9-3. Composite Back Trajectory Map for SDGA
-------
air traveled toward the monitoring site on a sampling day. Each concentric circle around the site
in Figure 9-3 represents 100 miles.
The following observations can be made from Figure 9-3:
• The back trajectories originated from a variety of directions at SDGA.
• The 24-hour airshed domain was somewhat large at SDGA, with trajectories
originating as far away as Texas, or greater than 600 miles away.
• The majority of the trajectories originated from within 300 miles of the site.
9.4.3 Wind Rose Analysis
Hourly wind data from the WB Hartsfield/Atlanta International Airport near the SDGA
monitoring site were uploaded into a wind rose software program, WRPLOT (Lakes, 2006).
WRPLOT produces a graphical wind rose from the wind data. A wind rose shows the frequency
of wind directions about a 16-point compass, and uses different shading to represent wind
speeds. Figure 9-4 is the wind rose for the SDGA monitoring site on days that sampling
occurred.
Observations from Figure 9-4 include:
• Hourly winds were predominantly out of the northwest (15 percent of observations),
west-northwest (12 percent), and west (10 percent) on sampling days.
• Wind speeds ranged from 7 to 11 knots on most sampling days.
• Calm winds (<2 knots) were recorded for only seven percent of the observations.
9.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could
not be performed because ERG did not analyze VOCs at this site. A mobile tracer analysis could
not be performed as this site did not sample for SNMOC.
9-10
-------
Figure 9-4. Wind Rose for SDGA Sampling Days
SOUTH ,-•
WIND SPEED
(Knots)
I | >=22
I I 17 - 21
• 11 - 17
^| 7- 11
I I -q- 7
^| 2- 4
Calms: 6.70%
-------
Table 9-5. Motor Vehicle Information for the Georgia Monitoring Site
Site
SDGA
2006 Estimated
County Population
723,602
Number of
Vehicles
Registered
458,290
Vehicles per Person
(Registration:
Population)
0.63
Population Within
10 Miles
728,937
Estimated 10 Mile
Vehicle
Ownership
461,669
Traffic Data
(Daily Average)
98,510
VO
to
-------
9.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population were obtained from the Georgia Department of
Revenue and Regulation and the U.S. Census Bureau, as shown in Table 9-5 in DeKalb, GA.
Table 9-5 also includes a vehicle registration to county population ratio (vehicles per person). In
addition, the population within 10 miles of each site is presented. An estimate of 10-mile vehicle
registration was computed using the 10-mile population surrounding the monitors and the vehicle
registration ratio. Finally, Table 9-5 contains the average daily traffic information, which
represents the average number of vehicles passing the monitoring sites on the nearest roadway to
each site on a daily basis.
Observations gleaned from Table 9-5 include:
• Compared to other UATMP sites, SDGA's county population and 10-mile radius
population were relatively high, falling roughly in the top 1/3 of sites.
• Vehicle registration and estimated vehicles per person were in the middle of the
range.
• Despite having only six sites with a lower population-to-vehicle ownership ratio, the
SDGA traffic count is the fourth highest of all UATMP sites.
9.6 Trends Analysis
A trends analysis could not be performed for SDGA as this site has not participated in the
UATMP for three consecutive years.
9.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
SDGA and where the annual average concentrations could be calculated (refer to Section 3.3.5
regarding the definition of an annual average). Annual averages, theoretical cancer and
noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 9-6. Additionally,
the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA for the pollutants
that failed at least one screen at SDGA were retrieved and are presented in Table 9-6. The NATA
data is presented for the census tract where the monitoring site is located.
9-13
-------
Table 9-6. Chronic Risk Summary for the Monitoring Site in Georgia
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC (jig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk (HQ)
Decatur, Georgia (SDGA) - Census Tract ID 13089023404
Hexavalent Chromium
0.012
0.0001
<0.01
0.48
<0.01
<0.01±<0.01
0.55
<0.01
VO
-------
The census tract information for SDGA is as follows:
• The SDGA monitoring site is located in census tract 13089023404.
• The population for the census tract where the SDGA monitoring site is located was
9,033, which represents less than two percent of De Kalb County's population in
2000.
The following observations can be made from Table 9-6:
• Both the NATA-modeled and annual average concentration for hexavalent chromium
were less than 0.01 |ig/m3.
• In terms of cancer risk, the NATA-modeled and calculated cancer risks were very
similar (0.48 and 0.55 in-a-million, respectively).
Both noncancer hazard quotients were less than 0.01, suggesting very little risk for noncancer
health affects due to hexavalent chromium.
9.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 9-7 and 9-8 present a risk-
based assessment of the county-level emissions based on cancer and noncancer toxicity,
respectively. Table 9-7 presents the 10 pollutants with the highest emissions from the 2002 NEI,
the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with the
highest cancer risk (in-a-million) as calculated from the annual average. Table 9-8 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer table, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer and noncancer risk based on each site's annual average is limited to those pollutants for
which each respective site sampled. In addition, the highest cancer and noncancer risks based on
annual averages are limited to those pollutants failing at least one screen.
9-15
-------
Table 9-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs
for SDGA
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(for De Kalb County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for De Kalb County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for SDGA)
Cancer Risk
Pollutant (in-a-million)
Decatur, Georgia - SDGA
Benzene
Formaldehyde
Dichloromethane
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
Naphthalene
Trichloroethylene
Poly cyclic Organic Matter as 15 -PAH
Bis(2-Ethylhexyl)Phthalate
721.36
228.22
118.50
81.24
71.24
52.62
17.83
11.99
4.07
1.58
Benzene
Arsenic
1,3 -Butadiene
Lead
Naphthalene
Hexavalent Chromium
Tetrachloroethylene
Poly cyclic Organic Matter as 15-PAH
Polycyclic Organic Matter as 7-PAH
Acetaldehyde
5.63E-03
2.61E-03
2.14E-03
1.37E-03
6.06E-04
5.87E-04
3.10E-04
2.24E-04
1.95E-04
1.79E-04
Hexavalent Chromium 0.55
VO
-------
Table 9-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for SDGA
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for De Kalb County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for De Kalb County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for SDGA)
Noncancer
Risk
Pollutant (HQ)
Decatur, Georgia - SDGA
Methyl Isobutyl Ketone
Toluene
Xylenes
Methyl Ethyl Ketone
Hydrochloric Acid
Benzene
Glycol Ethers
Ethylene Glycol
1,1,1 -Trichloroethane
Ethylbenzene
3,454.11
2,841.94
2,326.61
1,700.92
1,629.76
721.36
686.60
360.89
357.86
311.57
Acrolein
Hydrochloric Acid
1,3 -Butadiene
Glycol Ethers
Benzene
Formaldehyde
Xylenes
Arsenic
Acetaldehyde
Cyanide
727,132.35
81,488.19
35,618.84
34,330.15
24,045.18
23,287.32
23,266.13
20,258.05
9,026.98
8,419.85
Hexavalent Chromium <0 . 0 1
VO
-------
The following observations can be made from Table 9-7:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor and the
highest cancer toxicity-weighted emissions for De Kalb County, Georgia.
• Six of the top 10 pollutants (benzene, acetaldehyde, tetrachloroethylene, 1,3-
butadiene, naphthalene, and POM as 15-PAH) appeared on both the highest emitted
list and the highest toxicity-weighted emissions list, indicating that most of the
highest emitted pollutants were also the most toxic.
• Hexavalent chromium, the only pollutant sampled at SDGA, had a low cancer risk
based its annual average (0.55 in-a-million). However, this pollutant has the 6th
highest toxicity-weighted emissions in De Kalb County.
The following observations can be made from Table 9-8:
• Although methyl isobutyl ketone and toluene were the highest emitted pollutants with
noncancer risk factors, neither pollutant ranked in the top 10 based on toxicity-
weighted emissions.
• Acrolein had the highest noncancer toxicity-weighted emissions, but did not appear in
the list of highest emitted pollutants.
• Hexavalent chromium did not rank in the top 10 highest emitted pollutants with
noncancer risk factors or the 10 highest noncancer toxicity-weighted emissions in De
Kalb County.
Georgia Pollutant Summary
• The only pollutant sampled at the Georgia site was hexavalent chromium.
• Hexavalent chromium failed 10 percent of screens and did not exceed its intermediate
risk/actor.
9-18
-------
10.0 Sites in Illinois
This section presents meteorological, concentration, and spatial trends for the UATMP
sites in Illinois (NBIL and SPIL), located in the Chicago-Naperville-Joliet, IL-IN-WI MSA.
More specifically, NBIL is located in Northbrook, Illinois and SPIL is located in Schiller Park,
which are both suburbs of Chicago. Figures 10-1 and 10-2 are topographical maps showing the
monitoring sites in their urban locations. Figure 10-3 identifies point source emission locations
within 10 miles of each site as reported in the 2002 NEI for point sources. As Figure 10-3
shows, the NBIL and SPIL sites are within several miles of each other, and are surrounded by
numerous point sources. Fuel combustion and surface coating processes are the most numerous
source category groups surrounding these sites.
Daily weather fluctuations are common for the Chicago area. The proximity of Chicago
to Lake Michigan offers moderating effects from the continental climate of the region. In the
summertime, afternoon lake breezes can cool the city when winds from the south and southwest
push temperatures upward. The origin of the air mass determines the amount and type of winter
precipitation. The largest snowfalls tend to occur when cold air masses flow southward over
Lake Michigan. Wind speeds average around 10 mph, but can be greater due to the winds
channeling between tall buildings downtown (Ruffner and Bair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The two weather stations are
Palwaukee Municipal Airport and O'Hare International Airport (WBAN 4838 and 94846,
respectively). Table 10-1 presents average meteorological conditions of temperature (average
maximum and average), moisture (average dew point temperature, average wet-bulb
temperature, and average relative humidity), pressure (average sea level pressure), and wind
information (average scalar wind speed) for the entire year and on days samples were taken.
Also included in Table 10-1 is the 95 percent confidence interval for each parameter. As shown
10-1
-------
Figure 10-1. Chicago, Illinois (NBIL) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
10-2
-------
Figure 10-2. Chicago, Illinois (SPIL) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
10-3
-------
Figure 10-3. Facilities Located Within 10 Miles of NBIL and SPIL
Legend
-& NBiLUATMPsite ^ SPIL UATMP site
Source Category Group (No. of Facilities)
A Agricultural Services Facility (5t
* Automotive Repair. Services. & Parking < 1)
. Business Services Facility j1)
C Chemicals & Allied Products Facility (11)
Z Electrical & Electronic Equipment Facility 116)
D Fabricated Metal Products Facility (21)
G Food & Kindred Products Facility (4)
d Food Stores i. 1)
F Fuel Combustion Industrial Facility (235)
H Furniture 6 Fixtures Facility (11
+ Health Services Facility (1 i
I incineration Industrial Facility (31)
J Industrial Machinery & Equipment Facility (211
Instruments & Related Products Facility (2)
<• integrated Iron & Steel Manufacturing Facility (4)
L Liquids Distribution Industrial Facility (28^
H Medical. Dental. & Hospital Equipment and Supplies (3s
B Mineral Products Processing Industrial Facility (10)
X Miscellaneous Manufacturing Industries (19)
Note; Due to facility density ami collocation, the total facilities
displayed may not represent aB facilities wilhin fhe area of interest.
10 mile radius County boundary
P Miscellaneous Processes Industrial Facility < 101)
\ Non-ferrous Metals Processing Industrial Facility (28)
©Paper & Allied Products (5)
O Personal Services (121
P Petroleum/Nat Gas Prod. & Refining Industrial Facility (2)
> Pharmaceutical Production Processes Industrial Facility (2)
V Polymers & Resins Production Industrial Facility |2)
Q Primary Metal Industries Facility (3)
R Printings Publishing Facility(30)
4 Production of Organic Qiemicals industrial Facility (4)
:: Pulp & Paper Production Facility (1)
Y Rubber S Miscellaneous Plastic Products Facility (8|
U Special Trade Contractors Facility (1)
U Stone, Clay. Glass. & Concrete Products (3)
S Surface Coafing Processes Industrial Facility (93)
+ Transportation by Air (2)
i U.S. Postal Service (1»
8 Utility Boilers (3)
1 V\&ste Treatment & Disposal Industrial Facility (5)
* Wood Furniture Facility (1)
10-4
-------
Table 10-1. Average Meteorological Conditions near the Monitoring Sites in Illinois
Site
NBIL
SPIL
WBAN
04838
94846
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
59.02
±1.88
57.60
±4.56
60.02
±1.91
59.47
±4.69
Average
Temperature
(»F)
51.43
±1.77
50.09
±4.14
52.32
±1.80
51.61
±4.27
Average
Dew Point
Temperature
(°F)
41.09
±1.75
39.89
±3.99
40.99
±1.75
40.48
±3.94
Average
Wet Bulb
Temperature
(»F)
46.42
±1.61
45.19
±3.71
46.78
±1.61
46.14
±3.78
Average
Relative
Humidity
(%)
70.39
±1.22
70.88
±3.01
68.07
±1.24
68.92
±3.16
Average
Sea Level
Pressure
(mb)
1016.34
±0.74
1016.14
±1.70
1015.75
±0.74
1015.72
±1.68
Average
Scalar Wind
Speed
(kt)
7.01
±0.29
7.06
±0.72
8.01
±0.30
8.00
±0.76
-------
in Table 10-1, average meteorological conditions on sampling days were fairly representative of
average weather conditions throughout the year.
10.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Illinois
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006b). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. Table 10-2 presents the pollutants that
failed at least one screen at the Illinois monitoring sites. NBIL sampled for VOC, carbonyls,
SNMOC, metals (PMio), and hexavalent chromium; SPIL sampled for VOC and carbonyls only.
The following observations are shown in Table 10-2:
• The number of pollutants failing the screen varied by site.
• Nineteen pollutants with a total of 432 measured concentrations failed screens at
NBIL.
• Thirteen pollutants with a total of 426 measured concentrations failed screens at
SPIL.
• The pollutants of interest, which are highlighted in gray, also varied by site, yet the
following nine pollutants of interest were common to both sites: benzene, acrolein,
formaldehyde, carbon tetrachloride, 1,3-butadiene, acetaldehyde, tetrachloroethylene,
/>-dichlorobenzene, and trichloroethylene.
• Of the nine pollutants that were common between the two sites, three pollutants of
interest (benzene, carbon tetrachloride, and acrolein) had 100 percent of their
measured detections fail screens.
• Of the pollutants with at least one failed screen, 54 percent of concentrations failed
screens at NBIL, while 78 percent failed screens at SPIL.
10-6
-------
Table 10-2. Comparison of Measured Concentrations and EPA Screening
Values for the Illinois Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Northbrook, Illinois - NBIL
Benzene
Carbon Tetrachloride
Acetaldehyde
Arsenic (PM10)
1,3 -Butadiene
Formaldehyde
Acrolein
Tetrachloroethylene
Manganese (PM10)
/>-Dichlorobenzene
Trichloroethylene
Cadmium (PM10)
Hexavalent Chromium
Acrylonitrile
Bromomethane
Hexachloro- 1 ,3 -butadiene
Nickel (PM10)
1 ,2-Dichloroethane
1 , 1 ,2,2-Tetrachloroethane
Total
60
60
58
53
37
35
34
33
25
14
4
4
4
3
2
2
2
1
1
432
60
60
61
62
44
61
34
48
62
35
35
62
50
3
55
2
62
1
1
798
100.00
100.00
95.08
85.48
84.09
57.38
100.00
68.75
40.32
40.00
11.43
6.45
8.00
100.00
3.64
100.00
3.23
100.00
100.00
54.14
13.89
13.89
13.43
12.27
8.56
8.10
7.87
7.64
5.79
3.24
0.93
0.93
0.93
0.69
0.46
0.46
0.46
0.23
0.23
13.89
27.78
41.20
53.47
62.04
70.14
78.10
85.65
91.44
94.68
95.60
96.53
97.45
98.15
98.61
99.07
99.54
99.77
100.00
Schiller Park, Illinois - SPIL
Benzene
Carbon Tetrachloride
Acetaldehyde
1,3 -Butadiene
Formaldehyde
Tetrachloroethylene
Acrolein
/>-Dichlorobenzene
Trichloroethylene
Hexachloro- 1 , 3 -butadiene
Acrylonitrile
Ethyl Aery late
Dichloromethane
Total
61
61
59
58
55
49
41
18
16
4
2
1
1
426
61
61
60
58
56
59
41
39
47
4
2
1
59
548
100.00
100.00
98.33
100.00
98.21
83.05
100.00
46.15
34.04
100.00
100.00
100.00
1.69
77.74
14.32
14.32
13.85
13.62
12.91
11.50
9.62
4.23
3.76
0.94
0.47
0.23
0.23
14.32
28.64
42.49
56.10
69.01
80.52
90.14
94.37
98.12
99.06
99.53
99.77
100.00
10-7
-------
10.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. The daily and seasonal averages are presented in
Table 10-3. Annual averages are presented and discussed in further detail in later sections.
The following observations for NBIL are shown in Table 10-3:
• Formaldehyde had the highest average concentration by mass (2.72 ± 2.88 |ig/m3),
followed by acetaldehyde (0.98 ± 0.10 |ig/m3) and carbon tetrachloride (0.71 ± 0.05
|ig/m3).
• Seasonal averages for formaldehyde showed a wide variation of results with a large
confidence interval for the highest average (winter, 7.03 ± 10.69 |ig/m3).
• Most of the pollutants of interest's seasonal averages varied little from their daily
averages.
The following observations for SPIL are shown in Table 10-3:
• The pollutant with the highest daily average was formaldehyde (14.71 ± 6.59 |ig/m3).
Formaldehyde's daily average concentration was significantly higher than any of the
other pollutants of interest. The highest seasonal averages of formaldehyde occurred
in the summer (24.09 ± 13.52 |ig/m3) and spring (19.96 ± 19.33 |ig/m3). However,
the large confidence intervals indicate that outliers may be affecting these averages.
• The other seasonal averages did not vary much from season to season, if the
confidence interval was considered.
10-8
-------
Table 10-3. Daily and Seasonal Averages for the Pollutants of Interest for the Illinois Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Ug/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Ug/m3)
Conf.
Int.
Autumn
Avg
(Hg/m3)
Conf.
Int.
Northbrook, Illinois - NBIL
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Cadmium (PM10)
Carbon Tetrachloride
/>-Dichlorobenzene
Formaldehyde
Hexavalent Chromium
Manganese (PM10)
Tetrachloroethylene
Trichloroethylene
61
34
62
60
44
62
60
35
61
50
62
48
35
61
60
62
60
60
62
60
60
61
59
62
60
60
0.98
0.35
O.01
0.59
0.07
<0.01
0.71
0.17
2.72
0.01
0.01
0.41
0.23
0.10
0.07
O.01
0.07
0.01
O.01
0.05
0.09
2.88
0.01
O.01
0.15
0.08
0.91
0.18
O.01
0.63
0.06
O.01
0.59
NR
7.03
0.01
O.01
0.31
0.12
0.16
0.07
O.01
0.12
0.02
O.01
0.06
NR
10.69
0.01
O.01
0.27
0.07
0.92
NR
O.01
0.52
0.05
O.01
0.63
NR
0.97
0.01
0.01
0.24
NR
0.15
NR
O.01
0.13
0.01
O.01
0.08
NR
0.24
0.01
O.01
0.12
NR
0.86
0.31
O.01
0.51
0.04
O.01
0.78
0.13
1.43
0.01
O.01
0.55
0.13
0.21
0.14
O.01
0.15
0.01
O.01
0.12
0.11
0.53
0.01
O.01
0.39
0.07
1.24
0.32
O.01
0.68
0.06
O.01
0.84
0.11
1.15
0.01
O.01
0.27
0.19
0.24
0.08
O.01
0.17
0.01
O.01
0.05
0.06
0.33
0.01
O.01
0.08
0.16
Schiller Park, Illinois - SPIL
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
/>-Dichlorobenzene
Formaldehyde
Tetrachloroethylene
Trichloroethylene
60
41
61
58
61
39
56
59
47
60
61
61
61
61
61
60
61
61
2.22
1.01
0.92
0.15
0.72
0.11
14.71
0.77
0.53
0.34
0.32
0.09
0.02
0.05
0.02
6.59
0.21
0.17
1.52
NR
0.93
0.15
0.60
NR
3.44
0.33
0.22
0.27
NR
0.15
0.04
0.05
NR
0.88
0.13
0.09
3.04
NR
0.94
0.16
0.64
0.07
19.96
1.04
0.20
0.77
NR
0.23
0.06
0.05
0.02
19.33
0.60
0.15
2.82
1.20
0.81
0.13
0.80
0.12
24.09
0.94
0.71
0.74
0.41
0.20
0.03
0.08
0.06
13.52
0.30
0.41
1.61
0.75
1.01
0.14
0.86
0.08
8.83
0.70
0.55
0.48
0.52
0.15
0.02
0.10
0.03
3.86
0.39
0.28
NR = Not reportable due to low number of detections.
NA = Not available due to short sampling duration.
-------
10.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for the Illinois monitoring sites was evaluated
using ATSDR short-term (acute) and intermediate MRL and California EPA acute REL factors.
Acute risk is defined as exposures from 1 to 14 days while intermediate risk is defined as
exposures from 15 to 364 days. It is useful to compare preprocessed daily measurements to the
short-term MRL and REL factors, as well as compare seasonal averages to the intermediate
MRL. Of the pollutants with at least one failed screen, only acrolein and formaldehyde exceeded
either the acute and/or intermediate risk values. Non-chronic risk is summarized in Table 10-4.
The following observations about acrolein are shown in Table 10-4:
• All acrolein measured detections at the Illinois sites were greater than the ATSDR
acute MRL value of 0.11 |ig/m3 and all but one were greater than the California REL
value of 0.19 |ig/m .
3
• The average daily concentrations for NBIL and SPIL were 0.35 ± 0.07 |ig/m and
1.01 ± 0.32 |ig/m3, respectively. The SPIL average is an order of magnitude higher
than either acute risk factor.
• The NBIL seasonal averages for acrolein (ranging from 0.18 ± 0.07 |ig/m3 in winter
to 0.32 ± 0.08 |ig/m3 in autumn) were greater than the intermediate risk factor of 0.09
|ig/m3.
• The two seasonal acrolein averages calculated for SPIL, 0.75 ± 0.52 |ig/m3 in autumn
and 1.20 ± 0.41 |ig/m3 in summer, were also greater than the intermediate risk factor.
The following observations about formaldehyde are shown in Table 10-3:
• One formaldehyde measured detection at NBIL exceeded the ATSDR acute MRL
value of 49 |ig/m3. However, the seasonal averages were all less than the
intermediate MRL.
• Four formaldehyde measured detections at the SPIL site were greater than the
ATSDR acute MRL and one measured detection was greater than the California REL
value of 94 |ig/m3. While no valid seasonal formaldehyde averages exceeded the
intermediate MRL, the seasons where the highest concentrations were measured are
easily discernable.
10-10
-------
Table 10-4. Non-Chronic Risk Summary for the Illinois Monitoring Sites
Site
NBIL
NBIL
SPIL
SPIL
Method
TO-15
TO-11A
TO-15
TO-11A
Pollutant
Acrolein
Formaldehyde
Acrolein
Formaldehyde
Daily
Average
(ug/m3)
0.35
±0.07
2.72
±2.88
1.01
±0.32
14.71
±6.59
ATSDR
Short-term
MRL
(ug/m3)
0.11
49
0.11
49
# of ATSDR
MRL
Exceedances
34
1
41
4
CAL
EPA
REL
Acute
(Mg/m3)
0.19
94
0.19
94
# of CAL
EPA REL
Exceedances
28
0
40
1
ATSDR
Intermediate-
term MRL
(ug/m3)
0.09
49.13
0.09
49.13
Winter
Average
(Mg/m3)
0.18
±0.07
7.03
±10.69
NR
3.44
±0.88
Spring
Average
(ug/m3)
NR
0.97
±0.24
NR
19.96
±19.33
Summer
Average
(Ug/m3)
0.31
±0.14
1.43
±0.53
1.20
±0.41
24.09
±13.52
Autumn
Average
(Ug/m3)
0.32
±0.08
1.15
±0.33
0.75
±0.52
8.83
±3.86
NR = Not reportable due to low number of detections.
NA = Not available due to short sampling duration.
-------
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of
concentration and wind direction. Acrolein concentrations exceeded the acute risk factors at
both NBIL and SPIL, and the acute risk factor for formaldehyde was exceeded at SPIL. Figures
10-4 and 10-5 are pollution roses for acrolein, and Figures 10-6 and 10-7 are pollution roses for
formaldehyde.
Observations gleaned from the acrolein pollution roses include:
• Nearly all acrolein concentrations exceeded the acute risk factors, which are indicated
by a dashed line (CalEPA REL) and solid line (AT SDR MRL).
• Figure 10-4 shows that high acrolein concentrations at NBIL occurred with winds
originating from a variety of directions. However, more of these high concentrations
occurred with winds having a westerly component. Major roadways and expressways
surround the NBIL monitoring site, although the area is primarily residential.
• Figure 10-5 shows that high acrolein concentrations at SPIL also occurred with winds
originating from a variety of directions. The highest acrolein concentration at SPIL
was recorded with northeasterly winds. Major roadways and highways are situated to
the north, east, and south of the SPIL monitoring site, and Chicago O'Hare
International Airport is located to the west.
Observations gleaned from the formaldehyde pollution roses include:
• Figure 10-6 shows that only one formaldehyde concentration exceeded the ATSDR
MRL at NBIL. This concentration was measured on January 5, 2006, on a day with
northwesterly winds. Figure 10-3 shows that there are several industrial sites located
to the northwest of NBIL.
• Figure 10-7 shows that four measured detections of formaldehyde at SPIL exceeded
the ATSDR acute risk factor, and one exceeded the CalEPA REL value. Figure 10-7
shows that the highest formaldehyde concentrations occurred with westerly or
southerly winds. Figure 10-3 shows that a very large number of industrial sources are
located to the west and south of SPIL.
10-12
-------
Figure 10-4. Acrolein Pollution Rose for NBIL
o
UJ
O (-I
J _ ^ ^a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,
NW
2.5
2.0
1.5
1.0
S 0.5
01
o
O 0.0
0.5
1
1.0
1.5
2.0
2.5
3.0
w
sw
,
— CA EPA REL (0.19 M9/m
— ATSDR MRL(0.11 |jg/m3
NE
**
Daily Ava Cone =0.35 ±0.07 ua/m3
SE
3.0
2.5
2.0
1.5
1.0
0.5 0.0 0.5
Pollutant Concentration
1.0
1.5
2.0
2.5
3.0
-------
Figure 10-5. Acrolein Pollution Rose for SPIL
1 NW N
4.0 — CA EPA REL (0. 1 9 |jg/m )
35 — ATSDRMRL(0.11 |jg/m3)
3.0 I
2.5
2.0
1.5
c
5 1.0 »
1 0.5 * * * * *^
8 w * ^
5 n n * , •£ /^
§ I r^
S 0-5 f
1 1-0
Q.
1.5 *
2.5
3.0
3.5
4.0
sw s
4 5 i™™™™™™™™™™™^^
NE
• •
Daily Avq Cone =1.01 ± 0.32 uq/m3 SE
_______________^^
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5
Pollutant Concentration
2.0
2.5 3.0 3.5 4.0 4.5
-------
Figure 10-6. Formaldehyde Pollution Rose for NBIL
NW
W
150.0
135.0
120.0
105.0
90.0
75.0
60.0
45.0
30.0
15.0
0.0
15.0
30.0
45.0
60.0
75.0
90.0
105.0
120.0
135.0
I sw
150.0
150.0 135.0
— CA EPA REL (94 pg/m3
— ATSDR MRL (49 |jg/m3
NE
Daily Ava Cone = 2.72 ±2.88ug/nT
SE
120.0 105.0 90.0 75.0 60.0 45.0 30.0 15.0 0.0 15.0 30.0 45.0 60.0 75.0 90.0 105.0 120.0 135.0 150.0
Pollutant Concentration
-------
Figure 10-7. Formaldehyde Pollution Rose for SPIL
175.0
150.0
125.0
— ATSDR MRL (49 |jg/m
50.0
75.0
100.0
125.0
150.0
sw
175.0
175.0 150.0 125.0 100.0
75.0 50.0 25.0 0.0 25.0
Pollutant Concentration
Daily Avg Cone = 14.71 ±6.59ug/m"
50.0 75.0 100.0 125.0 150.0 175.0
-------
10.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
10.4.1 Pearson Correlation Analysis
Table 10-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the Illinois monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for NBIL from Table 10-5:
• Most of the correlations between the pollutants of interest and the meteorological
parameters were less than 0.50 or greater than -0.50, which indicates that
meteorological conditions have little influence on the concentrations of these
pollutants.
• Nearly all of the correlations with scalar wind speed were moderately strong and
negative, indicating that as wind speed decreases, concentrations of the pollutants of
interest increase at NBIL.
The following observations are gathered for SPIL from Table 10-5:
• Strong positive correlations were calculated between formaldehyde and maximum,
average, dew point, and wet bulb temperatures, ranging from 0.55 to 0.59. This
indicates that concentrations of formaldehyde tend to increase as temperatures and
moisture content increase.
• The remainder of the Pearson correlations were generally weak.
• All the correlations with the scalar wind speed were negative, indicating that
concentrations tend to decrease as winds increase in magnitude.
10-17
-------
Table 10-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Illinois
Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar Wind
Speed
Northbrook, Illinois - NBIL
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
Cadmium (PM10)
Carbon Tetrachloride
Formaldehyde
Hexavalent Chromium
Manganese (PM10)
£>-Dichlorobenzene
Tetrachloroethylene
Trichloroethylene
44
61
34
62
60
62
60
61
50
62
35
48
35
-0.05
0.12
0.39
0.29
0.08
-0.09
0.38
-0.15
0.34
0.33
-0.06
0.24
0.21
-0.12
0.05
0.38
0.26
0.02
-0.11
0.38
-0.12
0.32
0.27
-0.03
0.21
0.16
-0.14
-0.05
0.34
0.22
0.04
-0.11
0.35
-0.11
0.25
0.11
-0.09
0.17
0.03
-0.13
0.00
0.36
0.24
0.03
-0.11
0.37
-0.12
0.29
0.21
-0.05
0.20
0.10
-0.01
-0.28
-0.12
-0.10
0.09
-0.02
-0.13
0.04
-0.15
-0.46
-0.21
-0.17
-0.36
-0.08
0.08
0.00
0.12
-0.03
0.09
0.01
0.03
0.13
0.19
0.23
-0.04
0.03
-0.38
-0.30
-0.33
-0.38
-0.32
-0.13
-0.27
0.13
-0.41
-0.34
0.14
-0.27
-0.07
Schiller Park, Illinois - SPIL
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Carbon Tetrachloride
Formaldehyde
£>-Dichlorobenzene
Tetrachloroethylene
Trichloroethylene
58
60
41
61
61
56
39
59
47
-0.15
0.43
0.44
-0.14
0.32
0.58
0.23
0.41
0.29
-0.18
0.42
0.45
-0.14
0.36
0.59
0.27
0.40
0.31
-0.19
0.31
0.41
-0.13
0.35
0.55
0.21
0.37
0.29
-0.19
0.38
0.44
-0.14
0.35
0.58
0.24
0.40
0.30
0.00
-0.33
-0.19
0.08
-0.07
-0.19
-0.18
-0.17
-0.12
-0.09
0.00
-0.03
0.12
0.06
0.03
0.05
0.01
-0.05
-0.28
-0.27
-0.02
-0.32
-0.21
-0.17
-0.15
-0.16
-0.25
o
oo
-------
10.4.2 Composite Back Trajectory Analysis
Figures 10-8 and 10-9 are composite back trajectory maps for the Illinois monitoring sites
for the days on which sampling occurred. Each line represents the 24-hour trajectory along
which a parcel of air traveled toward the monitoring site on a sampling day. Each concentric
circle around the sites in Figures 10-8 and 10-9 represents 100 miles.
The following observations can be made from Figures 10-8 and 10-9:
• The back trajectories originated from a variety of directions at NBIL and SPIL,
although less frequently from the east.
• The 24-hour airshed domain for these sites is rather large, with trajectories originating
as far away as Manitoba, Canada, or over 800 miles away.
• Roughly 72 percent of the trajectories originated within 400 miles of the sites; and
nearly 90 percent within 500 miles from the Illinois monitoring sites.
10.4.3 Wind Rose Analysis
Hourly wind data from the weather station at Paulwakee Municipal Airport near NBIL
and Chicago O'Hare International Airport near SPIL were uploaded in a wind rose software
program, WRPLOT (Lakes, 2006). WRPLOT produces a graphical wind rose from the wind
data. A wind rose shows the frequency of wind directions about a 16-point compass, and uses
different shading to represent wind speeds. Figure 10-10 and 10-11 are the wind roses for the
NBIL and SPIL monitoring sites on days that sampling occurred.
Observations from Figure 10-10 for NBIL include:
• Hourly winds near NBIL were predominantly out of the west (10 percent of
observations) and south (9 percent) on sampling days.
• Wind speeds frequently ranged from 7 to 11 knots on days samples were taken. Calm
winds (< 2 knots) were recorded for 14 percent of observations.
10-19
-------
Figure 10-8. Composite Back Trajectory Map for NBIL
o
O
-------
Figure 10-9. Composite Back Trajectory Map for SPIL
-
o
-------
Figure 10-10. Wind Rose for NBIL Sampling Days
to
to
•SOUTH --'
WIND SPEED
(Knots)
I | >=22
I I 17 - 21
• 11 - 17
^| 7- 11
I I A- 7
^| 2- 4
Calms: 13.68%
-------
Figure 10-11. Wind Rose for SPIL Sampling Days
o
to
-------
Observations from Figure 10-11 for SPIL include:
• Hourly winds near SPIL were similar to NBIL, although they were measured at two
different weather stations.
• Winds were predominantly out of the west (11 percent of observations) and south
(10 percent) on sampling days.
• Wind speeds frequently ranged from 7 to 11 knots on sampling days. Calm winds
were recorded for 8 percent of observations.
10.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; BTEX analysis; and
acetylene-ethylene mobile tracer analysis.
10.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Cook County, IL were obtained from
the Illinois Secretary of State and the U.S. Census Bureau, and are summarized in Table 10-6.
Table 10-6 also includes a vehicle registration to county population ratio (vehicles per person).
In addition, the population within 10 miles of each site is presented. An estimation of 10-mile
vehicle registration was computed using the 10-mile population surrounding the monitor and the
vehicle registration ratio. Finally, Table 10-6 contains the average daily traffic information,
which represents the average number of vehicles passing the monitoring sites on the nearest
roadway to each site on a daily basis.
Observations gleaned from Table 10-6 include:
• The SPIL monitoring site has more than twice the population residing within 10 miles
than NBIL, and therefore a significantly higher estimated 10-mile vehicle ownership.
• The SPIL site experiences a significantly higher daily traffic volume than NBIL, as
well as the highest traffic volume among all UATMP sites.
• Figure 10-2 shows that SPIL resides near a major interstate close to Chicago's
O'Hare International Airport.
10-24
-------
Table 10-6. Motor Vehicle Information for the Illinois Monitoring Sites
Site
NBIL
SPIL
2006 Estimated
County
Population
5,288,655
5,288,655
Number of
Vehicles Registered
2,133,068
2,133,068
Vehicles per Person
(Registration:
Population)
0.40
0.40
Population
Within 10 Miles
879,379
2,074,707
Estimated 10 mile
Vehicle Ownership
354,679
836,790
Traffic Data
(Daily Average)
29,600
214,900
to
-------
10.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban
area-to-urban area (for more information on this study, refer to section 3.2.1.4). Table 3-12 and
Figure 3-4 depict the average concentration ratios of the roadside study and compares them to
the concentration ratios at each of the monitoring sites in an effort to characterize the impact of
on-road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• Like the roadside study, the toluene-ethylbenzene is the highest ratio for both NBIL
and SPIL (6.78 ± 0.74 and 7.09 ± 0.51, respectively).
• The benzene-ethylbenzene ratios (5.74 ± 0.58 and 3.30 ± 0.64) are greater than the
xylenes-ethylbenzene ratios (3.40 ± 0.19 and 3.54 ± 0.16) for these sites, which is
inconsistent with those of the roadside study.
10.5.3 Mobile Tracer Analysis
As previously stated, NBIL sampled for SNMOC in addition to VOC. Acetylene is a
compound that is primarily emitted from mobile sources, while ethylene is emitted from mobile
sources, petroleum refining facilities, and natural gas distribution facilities. Tunnel studies
conducted on mobile source emissions have found that ethylene and acetylene are typically
present in a 1.7 to 1 ratio. (For more information, please refer to Section 3.2.1.3)
Table 3-11 shows:
• NBIL's ethylene-acetylene ratio, 1.74, is slightly higher than the 1.7 ratio. The
similarities in these ratios suggest that mobile sources are influencing the air quality
at the NBIL monitoring site.
• But because this ratio is slightly higher than the tunnel study, there may be other
sources of ethylene contributing to this area's air quality.
10.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
10-26
-------
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. Both
Illinois sites have participated in the UATMP since 2003. Figures 10-12 and 10-13 present the
trends analysis for formaldehyde, benzene, and 1,3-butadiene for NBIL and SPIL, respectively.
The following observations can be made from Figures 10-12 and 10-13:
• Prior to 2005, the Illinois sites sampled only VOCs, therefore no formaldehyde trend
can be evaluated at this time since only two years of formaldehyde data are available.
• For NBIL, the average 1,3-butadiene concentration has been decreasing since 2004.
Although the large confidence interval for the 2004 average benzene concentration
makes it difficult to discern an overall trend, the average benzene concentration
decreased between 2005 and 2006.
• As illustrated in Figure 10-13, the average concentrations of benzene and 1,3-
butadiene for SPIL have changed little over the last three years.
10.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Illinois sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 10-7.
Additionally, the pollutants of interest are bolded. In addition to the annual averages and risks
based on 2006 monitoring data, data from EPA's 1999 NATA were retrieved and are also
presented in Table 10-7. The NATA data is presented for the census tract where the monitoring
site is located.
The census tract information for the Illinois sites is as follows:
• The census tract for NBIL is 17031801500, which had a population of 6,227, which
represents approximately 0.1 percent of the Cook County population in 2000.
• The census tract for SPIL is 17031811600, which had a population of 6,372, which
also represents approximately 0.1 percent of the county population in 2000.
10-27
-------
to
oo
Q.
Q.
O
'&
ro
o
O
O)
Figure 10-12. Comparison of Yearly Averages for the NBIL Monitoring Site
2003
2004
2005
2006
Year
ni,3-Butadiene
I Benzene
D Formaldehyde
-------
Figure 10-13. Comparison of Yearly Averages for the SPIL Monitoring Site
o
to
ou
•^n
9^
a.
_g.
c
O on
Doncentrati
->• h
n c
o
i_
in
c _
2003 2004 2005
Year
D1,3-Butadiene • Benzene
y
-L
2006
D Formaldehyde
-------
Table 10-7. Chronic Risk Summary for the Monitoring Sites in Illinois
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk
(HQ)
Northbrook, Illinois (NBIL) - Census Tract ID 17031801500
Acetaldehyde
Acrolein
Acrylonitrile
Arsenic*
Benzene
Bromomethane
1,3-Butadiene
Cadmium*
Carbon Tetrachloride
p-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Hexavalent Chromium
Manganese*
Nickel*
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Trichloroethylene
0.0000022
NR
0.000068
0.0043
0.0000078
NR
0.00003
0.0018
0.000015
0.000011
0.000026
5.5E-09
0.000022
0.012
0.00016
0.000058
0.0000059
0.000002
0.009
0.00002
0.002
0.00003
0.03
0.005
0.002
0.00002
0.04
0.8
2.4
0.0098
0.09
0.0001
0.00005
0.000065
NR
0.27
0.6
2.72
0.18
0.01
0.01
2.64
0.14
0.32
0.24
0.22
0.04
0.05
2.73
O.01
O.01
0.67
0.36
0.08
0.24
0.26
5.99
NR
0.06
0.06
20.55
NR
9.59
0.44
3.23
0.44
1.25
0.02
0.03
0.74
NR
0.06
4.44
1.44
0.52
0.30
8.98
0.01
O.01
0.09
0.03
0.16
0.01
0.01
0.01
O.01
0.28
O.01
O.01
0.01
0.01
NR
O.01
O.01
0.98 ±0.10
0.25 ± 0.05
0.06 ±0.01
O.01±O.01
0.59 ±0.07
2.07 ±3.91
0.06 ±0.01
O.01±O.01
0.71 ±0.05
0.11 ±0.05
0.03 ±O.01
2.72 ±2.88
0.10 ±0.05
O.01±O.01
0.01 ±0.01
O.01±O.01
0.05 ±0.01
0.34 ±0.13
0.15 ±0.05
2.16
NR
4.39
3.68
4.58
NR
1.68
0.37
10.58
1.20
0.82
0.01
2.21
0.45
NR
0.19
2.69
2.00
0.30
0.11
12.46
0.03
0.03
0.02
0.41
0.03
0.01
0.02
0.01
O.01
0.28
O.01
O.01
0.12
0.02
NR
O.01
O.01
o
o
-------
Table 10-7. Chronic Risk Summary for the Monitoring Sites in Illinois (Continued)
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk
(HQ)
Schiller Park, Illinois (SPIL) - Census Tract ID 17031811600
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-D ichlo rob enzene
Dichloromethane
Ethyl Aery late
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
Trichloroethylene
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
0.00000047
0.000014
5.5E-09
0.000022
0.0000059
0.000002
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
1
NR
0.0098
0.09
0.27
0.6
3.33
0.22
0.01
2.79
0.31
0.21
0.06
1.15
O.01
2.99
O.01
0.41
1.72
7.32
NR
0.05
21.79
9.22
3.16
0.64
0.54
O.01
0.02
0.03
2.42
3.45
0.37
11.08
0.01
0.09
0.15
0.01
0.01
O.01
NR
0.30
O.01
0.01
O.01
2.22 ±0.34
0.72 ± 0.24
0.06 ±0.01
0.92 ±0.09
0.15 ±0.02
0.72 ±0.05
0.07 ± 0.02
0.50 ±0.12
0.02 ±O.01
13.73 ±6.22
0.08 ±0.01
0.75 ±0.21
0.42 ±0.14
4.89
NR
4.24
7.20
4.39
10.82
0.82
0.24
0.33
0.08
1.66
4.41
0.83
0.25
35.81
0.03
0.03
0.07
0.02
0.01
O.01
NR
1.40
O.01
0.01
O.01
*Metals sampled were sampled with PM10 filters
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
-------
The following observations can be made for NBIL from Table 10-7:
• The pollutants with the top 3 annual averages by mass concentration were
formaldehyde (2.72 ± 2.88 |ig/m3), bromomethane (2.07 ± 3.91 |ig/m3), and
acetaldehyde (3.02 ± 0.78 |ig/m3).
• The pollutants with the highest cancer risks were not these pollutants. The highest
theoretical cancer risks were calculated for carbon tetrachloride (10.58 in-a-million),
benzene (4.58), and acrylonitrile (4.39).
• According to the 1999 NATA, benzene (20.55 in-a-million), 1,3-butadiene (9.59),
and acetaldehyde (5.99) had the highest cancer risk for pollutants that failed screens
at NBIL.
• Acrolein was the only pollutant that exhibited a noncancer HQ greater than 1,
according to both the 2006 annual average and the 1999 NATA. All other noncancer
HQs were less than 0.50.
The following observations can be made for SPIL from Table 10-7:
• Although formaldehyde had the highest annual averages by mass concentration
(13.73 ± 6.22 |ig/m3), the highest theoretical cancer risks were calculated for carbon
tetrachloride (10.82 in-a-million), benzene (7.20), and acetaldehyde (4.89).
• According to the 1999 NATA, benzene (21.79 in-a-million), 1,3-butadiene (9.22),
and acetaldehyde (7.32) had the highest cancer risk for pollutants that failed screens
at SPIL. These risk values were very similar to those for NBIL.
• Acrolein and formaldehyde exhibited theoretical noncancer HQ greater than 1 (35.81
and 1.40, respectively). SPIL has the second highest noncancer HQ for formaldehyde
of all UATMP sites, second only to INDEM (6.32). All other noncancer HQs were
less than 0.30.
• According to the 1999 NATA, only acrolein had a noncancer HQ greater than 1.0
(11.08).
10.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 10-8 and 10-9 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 10-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
10-32
-------
Table 10-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs
for the Monitoring Sites in Illinois
Top 10 Total Emissions for Pollutants
with Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted
Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer Risk
(in-a-million)
Northbrook, Illinois (NBIL) - Cook County
Benzene
Formaldehyde
Tetrachloroethylene
Acetaldehyde
£>-Dichlorobenzene
Trichloroethylene
Dichloromethane
1,3 -Butadiene
Naphthalene
1 ,3 -Dichloropropene
1923.92
1311.52
1167.21
634.98
523.44
420.87
316.79
236.69
219.02
89.84
Benzene
Arsenic
Coke Oven Emissions
Naphthalene
1,3 -Butadiene
Tetrachloroethylene
£>-Dichlorobenzene
Hexavalent Chromium
Cadmium
Lead
1.50E-02
1.25E-02
1.04E-02
7.45E-03
7.10E-03
6.89E-03
5.76E-03
5.66E-03
2.51E-03
2.15E-03
Carbon Tetrachloride
Benzene
Acrylonitrile
Arsenic
1 , 1 ,2,2-Tetrachloroethane
Hexachloro- 1 ,3 -butadiene
Acetaldehyde
Tetrachloroethylene
1,3 -Butadiene
£>-Dichlorobenzene
10.58
4.58
4.39
3.68
2.69
2.21
2.16
2.00
1.68
1.20
Schiller Park, Illinois (SPIL) - Cook County
Benzene
Formaldehyde
Tetrachloroethylene
Acetaldehyde
£>-Dichlorobenzene
Trichloroethylene
Dichloromethane
1,3 -Butadiene
Naphthalene
1 ,3 -Dichloropropene
1923.92
1311.52
1167.21
634.98
523.44
420.87
316.79
236.69
219.02
89.84
Benzene
Arsenic
Coke Oven Emissions
Naphthalene
1,3 -Butadiene
Tetrachloroethylene
£>-Dichlorobenzene
Hexavalent Chromium
Cadmium
Lead
1.50E-02
1.25E-02
1.04E-02
7.45E-03
7.10E-03
6.89E-03
5.76E-03
5.66E-03
2.51E-03
2.15E-03
Carbon Tetrachloride
Benzene
Acetaldehyde
Tetrachloroethylene
1,3 -Butadiene
Acrylonitrile
Hexachloro- 1 ,3 -butadiene
Trichloroethylene
£>-Dichlorobenzene
Ethyl Aery late
10.82
7.20
4.89
4.41
4.39
4.24
1.66
0.83
0.82
0.33
o
oo
-------
Table 10-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for the Monitoring Sites in Illinois
Top 10 Total Emissions for Pollutants
with Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted
Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on Annual
Average Concentrations
(Site-Specific)
Pollutant
Noncancer Risk
(HQ)
Northbrook, Illinois (NBIL) - Cook County
Toluene
Xylenes
Methanol
Methyl Ethyl Ketone
Benzene
Methyl Isobutyl Ketone
Hexane
Formaldehyde
Tetrachloroethylene
1,1,1 -Trichloroethane
7,837.72
5,082.62
3,404.01
3,215.93
1,923.92
1,483.77
1,332.45
1,311.52
1,167.21
1,137.26
Acrolein
Manganese
Formaldehyde
1,3 -Butadiene
Bromomethane
Nickel
Arsenic
Naphthalene
Acetaldehyde
Cadmium
3,193,594.06
153,628.02
133,828.14
118,344.25
113,356.00
100,856.60
96,523.58
73,005.50
70,553.24
69,789.79
Acrolein
Bromomethane
Formaldehyde
Manganese
Acetaldehyde
Acrylonitrile
Arsenic
1,3 -Butadiene
Benzene
Nickel
12.46
0.41
0.28
0.12
0.11
0.03
0.03
0.03
0.02
0.02
Schiller Park, Illinois (SPIL) - Cook County
Toluene
Xylenes
Methanol
Methyl Ethyl Ketone
Benzene
Methyl Isobutyl Ketone
Hexane
Formaldehyde
Tetrachloroethylene
1,1,1 -Trichloroethane
7,837.72
5,082.62
3,404.01
3,215.93
1,923.92
1,483.77
1,332.45
1,311.52
1,167.21
1,137.26
Acrolein
Manganese
Formaldehyde
1,3 -Butadiene
Bromomethane
Nickel
Arsenic
Naphthalene
Acetaldehyde
Cadmium
3,193,594.06
153,628.02
133,828.14
118,344.25
113,356.00
100,856.60
96,523.58
73,005.50
70,553.24
69,789.79
Acrolein
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Acrylonitrile
Benzene
Carbon Tetrachloride
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
Trichloroethylene
35.81
1.40
0.25
0.07
0.03
0.03
0.02
0.01
0.01
0.01
o
oo
-------
the highest cancer risk (in-a-million) as calculated from the annual average. Table 10-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. In addition, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average are limited to those pollutants for which each
respective site sampled. SPIL sampled for VOC and carbonyl compounds. NBIL sampled for
these pollutants as well, but also sampled for SNMOC, metals, and hexavalent chromium.
The following observations can be made from Table 10-8:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor, had the
highest cancer toxicity-weighted emissions, and had the second highest cancer risk
based on the 2006 annual average for both Illinois sites.
• Carbon tetrachloride had the highest cancer risk based on the 2006 annual average for
both NBIL and SPIL, yet this pollutant was neither one of the highest emitted nor one
of the most toxic based on the 2002 NEI emission inventory.
The following observations can be made from Table 10-9:
• Although toluene and xylenes were the highest emitted pollutants with noncancer risk
factors in Cook County, they did not rank in the top 10 based on toxicity-weighted
emissions or the annual average-based noncancer risk.
• Acrolein had the highest noncancer toxicity-weighted emissions in Cook County and
has the highest noncancer risks based on the 2006 annual average at both sites, but
does not appear in the list of highest emitted pollutants.
• Formaldehyde, which had the highest daily and annual averages at both sites, is one
of the 10 highest emitted pollutants in Cook County and is ranked third for noncancer
toxicity-weighted emissions.
10-35
-------
Illinois Pollutant Summary
• The pollutants of interest common to each Illinois site were acetaldehyde, acrolein,
benzene, 1,5'-butadiene, carbon tetrachloride, p-dichlorobenzene, formaldehyde,
tetrachloroethylene, and trichloroethylene.
• Formaldehyde had the highest daily average for each of the two Chicago sites (NBIL and
SPIL).
• Acrolein and formaldehyde exceeded the short-term risk factors at both Chicago sites.
• A comparison of benzene, 1,3-butadiene and formaldehyde concentrations for all years of
UATMP participation shows that concentrations of benzene decreased at NBIL between
2005 and 2006 and that concentrations of benzene and 1,3-butadiene have varied little at
SPIL.
10-36
-------
11.0 Sites in Indiana
This section presents meteorological, concentration, and spatial trends for the UATMP
sites in Indiana (IDIN, INDEM, ININ and WPIN). Three sites, IDIN, ININ and WPIN, are
located in Indianapolis. INDEM is located in Gary in the Chicago-Naperville-Joliet, IL-IN-WI
MSA. Figures 11-1 to 11-4 show topographical maps of the monitoring sites. Figures 11-5 and
11-6 identify point source emission locations within 10 miles of these sites that reported to the
2002 NEI for point sources. Figure 11-5 shows that IDIN and ININ are relatively close to each
other, and that WPIN is further northeast. The bulk of the industrial sources are located between
the three sites, and are predominately involved in fuel combustion industries. Due in part to
INDEM's proximity to Lake Michigan, most of the facilities near INDEM are located to the east
or west of the monitoring site. The bulk of these facilities are involved in fuel combustion
processes, mineral products processing, or liquids distribution, as shown in Figure 11-6.
The city of Indianapolis is located in the center of Indiana, and experiences a temperate
continental climate. Summers are warm and often humid, winters are chilly with occasional
Arctic outbreaks, and precipitation is spread rather evenly throughout the year. The prevailing
wind direction is southwesterly. Gary is located to the southeast of Chicago, and at the southern-
most tip of Lake Michigan. Gary's proximity to Lake Michigan is an important factor
controlling the weather of the area. In the summer, warm temperatures can be suppressed, while
cold winter temperatures are often moderated. Winds that blow across Lake Michigan and over
Gary in the winter can provide abundant amounts of lake-effect snow (Ruffner and Bair, 1987
and http://www.garychamber.com/geoclimate.asp).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The closest weather station
to the Indianapolis locations is the Indianapolis International Airport (WBAN 93819) and the
closest weather station to INDEM is located at Lancing Municipal Airport (WBAN 04879).
Table 11-1 presents average meteorological conditions of temperature (average maximum and
11-1
-------
Figure 11-1. Indianapolis, Indiana (IDIN) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
11-2
-------
Figure 11-2. Gary, Indiana (INDEM) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
11-3
-------
Figure 11-3. Indianapolis, Indiana (ININ) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
11-4
-------
Figure 11-4. Indianapolis, Indiana (WPIN) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
11-5
-------
Figure 11-5. Facilities Located within 10 Miles of IDIN, ININ, and WPIN
Hamilton
r™nty
J
><;;!*;
f
Hendrtcks
County
Morgan
-
Johnson
County
Legend
•jV IDIN UATMP site hfe WPIN UATMP site
•if- ININ UATMP site
Source Category Group (No. of Facilities)
c Chemicals & Allied Products Facility (8)
z Electrical & Electronic Equipment Facility (2)
D Fabricated Metal Products Facility (9)
F Fuel Combustion Industrial Facility (61)
i Incineration Industrial Facility (3)
J Industrial Machinery & Equipment Facility (1)
» integrated Iron & Steel Manufacturing Facility (3)
L Liquids Distribution Industrial Facility (5)
& Lumber & Wood Products Facility (1)
B Mineral Products Processing Industrial Facility (8)
x Miscellaneous Manufacturing Industries (2)
P Miscellaneous Processes Industrial Facility (6)
v Non-ferrous Metals Processing Industrial Facility (1)
Note; Due to faculty density and collocation, the total facilities
displayed may no? represent all facilities within the area of interest.
10 mile radius
County boundary
3 Pharmaceutical Production Processes Industrial Facility (3)
v Polymers S Resins Production Industrial Facility (2)
R Printing & Publishing Facility (5)
4 Production of Organic Chemicals Industrial Facility (6)
i Railroad Transportation (1)
v Rubber & Miscellaneous Plastic Products Facility (2)
u Stone, Clay. Glass. & Concrete Products (1 )
s Surface Coating Processes Industrial Facility (8)
? Unknown (2)
8 Utility Boilers (3)
' Waste Treatment & Disposal Industrial Facility (3)
r Wholesale Trade (2)
s Wholesale Trade - Durable Goods (1 }
A Wood Furniture Facility (1 )
11-6
-------
Figure 11-6. Facilities Located within 10 Miles of INDEM
Note; Due to facility density and allocation, the total facility
displayed may nol represent all facilities within the area of ir
Legend
-& INDEM UATMP site
Source Category Group (No. of Facilities)
: Business Services Facility (1)
C Chemicals & Allied Products Facility (2)
D Fabricated Metal Products Facility (3)
K Ferrous Metals Processing Industrial Facility (3)
f Fuel Combustion Industrial Facility (38)
J Industrial Machinery & Equipment Facility (2)
i- Integrated Iron & Steel Manufacturing Facility (1)
L Liquids Distribution Industrial Facility (12)
B Mineral Products Processing Industrial Facility (8)
x Miscellaneous Manufacturing Industries (1)
10 mile radius | | County boundary
P Miscellaneous Processes Industrial Facility (3)
\ Non-ferrous Metals Processing Industrial Facility (3)
2 Nonmetallic Minerals, Except Fuels (1)
P Petroleum/Nat. Gas Prod. & Refining Industrial Facility (2)
Q Primary Metal Industries Facility (3)
* Production of Inorganic Chemicals Industrial Facility (2)
» Railroad Transportation (1)
s Surface Coating Processes Industrial Facility (3)
8 Utility Boilers (4)
v Waste Treatment & Disposal Industrial Facility (2)
'• Wholesale Trade (1)
11-7
-------
Table 11-1. Average Meteorological Conditions near the Monitoring Sites in Indiana
Site
IDIN
INDEM
ININ
WPIN
WBAN
93819
04879
93819
93819
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(»F)
62.91
±1.74
51.06
±5.83
60.43
±1.83
58.65
±4.68
62.91
±1.74
50.88
±5.89
62.91
±1.74
70.33
± 13.47
Average
Temperature
(°F)
54.54
±1.69
43.44
±5.03
52.43
±1.72
50.36
±4.13
54.54
±1.69
42.86
±5.18
54.54
±1.69
64.18
±11.85
Average
Dew Point
Temperature
(°F)
44.26
±1.69
35.89
±4.93
43.13
± 1.72
41.42
±3.97
44.26
±1.69
34.60
±5.30
44.26
±1.69
59.05
±11.45
Average
Wet Bulb
Temperature
(°F)
49.34
±1.55
40.11
±4.52
47.88
±1.59
46.03
±3.72
49.34
±1.55
39.30
±4.74
49.34
±1.55
61.06
±11.24
Average
Relative
Humidity
(%)
70.93
±1.25
76.76
±5.92
73.12
±1.20
74.36
±3.46
70.93
±1.25
74.71
±6.04
70.93
±1.25
84.60
±4.40
Average
Sea Level
Pressure
(mb)
1016.37
±0.69
1017.17
±3.72
NA1
NA1
1016.37
±0.69
1018.84
±3.12
1016.37
±0.69
1013.03
±1.89
Average
Scalar Wind
Speed
(kt)
8.33
±0.32
9.35
±2.09
6.62
±0.36
6.54
±0.94
8.33
±0.32
9.12
±2.02
8.33
±0.32
7.92
±2.21
oo
Sea level pressure was not recorded at the Lancing Municipal Airport weather station.
-------
average), moisture (average dew point temperature, average wet-bulb temperature, and average
relative humidity), pressure (average sea level pressure), and wind information (average scalar
wind speed) for the entire year and on days samples were collected. Also included in Table 10-1
is the 95 percent confidence interval for each parameter. As shown in Table 11-1, average
meteorological conditions on sampling days at INDEM were fairly representative of average
weather conditions throughout the year. Table 11-1 shows that temperatures on sampling days at
ININ and ID IN appear colder than for temperatures for the entire year. This is due to these two
sites not beginning sampling until October. The temperatures on sampling days at WPIN appear
warmer than for the entire year; however, this site did not begin sampling until late June.
Temperatures for an entire year's worth of sampling days would likely look more similar to
those for the entire year.
11.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Indiana
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. The Indiana sites all sampled for carbonyl
compounds, but ININ and IDIN also sampled for metals, and ININ also sampled for hexavalent
chromium. Table 11-2 presents the pollutants that failed at least one screen at the Indiana
monitoring sites.
The following observations are shown in Table 11-2:
• While the pollutants of interest varied by location, two pollutants were identified as
pollutants of interest at all the sites. Formaldehyde failed 88 total screens and
acetaldehyde failed 89 total screens at all four sites.
• IDIN had seven pollutants with a total of 55 measured concentrations fail the screen.
11-9
-------
Table 11-2. Comparison of Measured Concentrations and EPA Screening Values for the
Indiana Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Stout Field, Indianapolis, Indiana - IDIN
Formaldehyde
Acetaldehyde
Arsenic (PM10)
Manganese (PM10)
Nickel (PM10)
Cadmium (PM10)
Cobalt (PM10)
Total
16
16
12
7
2
1
1
55
16
16
13
13
13
13
13
97
100.00
100.00
92.31
53.85
15.38
7.69
7.69
56.70
29.09
29.09
21.82
12.73
3.64
1.82
1.82
29.09
58.18
80.00
92.73
96.36
98.18
100.00
Gary, Indiana - INDEM
Acetaldehyde
Formaldehyde
Total
54
54
108
54
54
108
100.00
100.00
100.00
50.00
50.00
50.00
100.00
South Harding, Indianapolis, Indiana - ININ
Arsenic (PM10)
Acetaldehyde
Formaldehyde
Manganese (PM10)
Cadmium (PM10)
Hexavalent Chromium
Cobalt (PM10)
Total
16
14
14
9
3
2
1
59
16
14
14
16
16
11
16
103
100.00
100.00
100.00
56.25
18.75
18.18
6.25
57.28
27.12
23.73
23.73
15.25
5.08
3.39
1.69
27.12
50.85
74.58
89.83
94.92
98.31
100.00
Washington Park, Indianapolis, Indiana - WPIN
Acetaldehyde
Formaldehyde
Total
5
4
9
5
5
10
100.00
80.00
90.00
55.56
44.44
55.56
100.00
• INDEM had two pollutants fail a total of 108 screens.
• Seven pollutants with a total of 59 measured concentrations failed the screen at ININ.
• Two pollutants with a total of 9 measured concentrations failed the screen at WPIN.
11.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average can be calculated. The seasonal average includes 1/2
11-10
-------
MDLs substituted for all non-detects. A seasonal average will not be calculated for pollutants
with less than seven measured detections in a respective season. Finally, the annual average is
the average concentration of all measured detections and 1/2 MDLs substituted for non-detects.
The resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal averages are presented in
Table 11-3. Annual averages are presented and discussed in further detail in later sections.
Table 11-3 shows the following:
• With the exception of hexavalent chromium, the pollutants of interest were detected
in 100 percent of the samples collected at all four Indiana monitoring sites.
• The daily average concentration of formaldehyde at INDEM was significantly higher
than any other pollutant concentration measured (61.91 ± 17.11 |ig/m3).
• The INDEM formaldehyde seasonal averages show that the spring and summer
formaldehyde averages (103.33 ± 41.60 |ig/m3 and 101.00 ± 42.64 |ig/m3,
respectively) were an order of magnitude higher than the other seasons, and two
orders of magnitude higher than any concentration measured at the other sites.
• INDEM had the highest daily formaldehyde average compared to all UATMP sites,
which is consistent with the 2005 measurements. Formaldehyde also had the highest
daily average at ININ, ID IN, and WPIN, although significantly lower in magnitude
than INDEM.
• Due to the sampling start dates of the Indianapolis sites, few seasonal averages could
be calculated.
11.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for the Indiana monitoring sites was
evaluated using ATSDR short-term (acute) and intermediate MRL and California EPA REL
factors. Acute risk is defined as exposures from 1 to 14 days while intermediate risk is defined
as exposures from 15 to 364 days. It is useful to compare preprocessed daily measurements to
the short-term MRL and REL factors, as well as compare seasonal averages to the intermediate
MRL. Of the two pollutants with at least one failed screen, only formaldehyde at INDEM
11-11
-------
Table 11-3. Daily and Seasonal Averages for the Pollutants of Interest for the Indiana Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Ug/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Ug/m3)
Conf.
Int.
Autumn
Avg
(Ug/m3)
Conf.
Int.
Indianapolis, Indiana - IDIN
Acetaldehyde
Arsenic (PM10)
Formaldehyde
Manganese (PM10)
Nickel (PM10)
16
13
16
13
13
16
13
16
13
13
1.78
0.01
2.21
0.01
0.01
0.42
0.01
0.57
O.01
0.01
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
1.94
0.01
2.59
0.01
0.01
0.59
0.01
0.76
O.01
0.01
Gary, Indiana - INDEM
Acetaldehyde
Formaldehyde
54
54
54
54
4.63
61.91
0.56
17.11
2.85
16.73
0.30
2.70
5.24
103.33
0.74
41.60
6.09
101.00
1.13
42.64
5.03
48.16
1.24
20.78
Indianapolis, Indiana - ININ
Acetaldehyde
Arsenic (PM10)
Cadmium (PM10)
Formaldehyde
Hexavalent Chromium
Manganese (PM10)
14
16
16
14
11
16
14
16
16
14
16
16
1.86
O.01
0.01
2.24
O.01
0.01
0.45
O.01
0.01
0.55
O.01
0.01
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
2.11
O.01
0.01
2.57
NR
0.01
0.63
O.01
0.01
0.73
NR
0.01
Washington Park, Indiana - WPIN
Acetaldehyde
Formaldehyde
5
5
5
5
1.27
1.43
0.26
0.42
NA
NA
NA
NA
NA
NA
NA
NA
NR
NR
NR
NR
NR
NR
NR
NR
NR = Not reportable due to low number of measured detections.
NA = Not available due to short sampling duration.
-------
Table 11-4. Non-Chronic Risk Summary for the Indiana Monitoring Sites
Site
INDEM
Method
TO-11A
Pollutant
Formaldehyde
Daily
Average
(ug/m3)
61.91 ±
17.11
ATSDR
Short-term
MRL
(ug/m3)
49
# of ATSDR
MRL
Exceedances
21
CAL EPA
REL
Acute
(ug/m3)
94
# of CAL EPA
REL
Exceedances
11
ATSDR
Intermediate-
term MRL
(Ug/m3)
40
Winter
Average
(Ug/m3)
16.73
±2.70
Spring
Average
(Ug/m3)
103.33
±41.60
Summer
Average
(ug/m3)
101.00
± 42.64
Autumn
Average
(ug/m3)
48.16
± 20.78
-------
exceeded both the acute and intermediate risk values, and its non-chronic risk is summarized in
Table 11-4.
The following observations about formaldehyde at INDEM are shown in Table 11-4.
• Twenty-one formaldehyde measured detections exceeded the ATSDR MRL acute
risk value of 49 |ig/m3 and eleven exceeded the California EPA REL value of 94
|ig/m3.
• The daily average formaldehyde concentration was 61.91 ± 17.11 |ig/m3, which is
more than the ATSDR MRL value, but less than the California EPA REL value.
• For the intermediate formaldehyde risk, seasonal averages were compared to the
ATSDR intermediate value of 40 |ig/m3. Three seasonal averages exceeded the
ATSDR Intermediate MRL. The spring and summer averages were more than two
times the ATSDR Intermediate MRL.
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of daily
concentration and daily average wind direction. Formaldehyde concentrations at INDEM
exceeded the short-term risk factors. Figure 11-7 is a pollution rose for formaldehyde for
INDEM.
Observations gleaned from the formaldehyde pollution rose for INDEM include:
• Many concentrations exceeded the acute risk factors, indicated by a dashed
(CALEPA REL) and solid line (ATSDR MRL).
• The concentrations on the pollution rose are scattered around the center, a pattern
consistent with mobile source attribution. However, the highest concentrations of
formaldehyde occurred with southwesterly, northwesterly, or northeasterly winds.
• INDEM is located in a very industrialized area, and major interstates are located just
south of the monitoring site. In addition, several railway lines criss-cross the area
surrounding the monitoring site (refer to Figure 11-2).
11.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson Correlation Coefficients between meteorological parameters
11-14
-------
Figure 11-7. Formaldehyde Pollution Rose for INDEM
300.0
250.0
200.0
Daily Avq Cone = 61.91 ±17.11 uq/m SE
250.0
sw
300.0
300.0 250.0 200.0
150.0 100.0 50.0 0.0 50.0
Pollutant Concentration
100.0
150.0
200.0
250.0
300.0
-------
Table 11-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Indiana
Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Stout Field, Indianapolis, Indiana - IDIN
Acetaldehyde
Arsenic (PM10)
Formaldehyde
Manganese (PM10)
Nickel (PM10)
16
13
16
13
13
0.58
0.55
0.79
0.17
0.41
0.57
0.51
0.75
0.25
0.47
0.45
0.42
0.54
0.11
0.47
0.53
0.48
0.67
0.20
0.48
-0.23
-0.22
-0.41
-0.30
0.04
0.23
0.14
0.35
0.28
0.16
-0.70
-0.44
-0.67
-0.37
-0.15
Gary, Indiana - INDEM
Acetaldehyde
Formaldehyde
54
54
0.61
0.50
0.58
0.47
0.55
0.46
0.57
0.46
-0.10
-0.04
NA1
NA1
-0.24
-0.07
South Harding, Indianapolis, Indiana - ININ
Acetaldehyde
Arsenic (PM10)
Cadmium (PM10)
Formaldehyde
Hexavalent Chromium
Manganese (PM10)
14
16
16
14
11
16
0.74
0.58
0.66
0.85
-0.49
0.40
0.68
0.55
0.59
0.77
-0.59
0.27
0.52
0.45
0.44
0.56
-0.66
-0.06
0.62
0.51
0.53
0.69
-0.63
0.12
-0.37
-0.21
-0.34
-0.48
-0.29
-0.75
0.26
0.25
0.27
0.24
0.52
0.58
-0.51
-0.64
-0.38
-0.42
0.03
-0.41
Washington Park, Indianapolis, Indiana - WPIN
Acetaldehyde
Formaldehyde
5
5
0.65
0.74
0.59
0.78
0.50
0.78
0.54
0.78
-0.94
-0.37
0.85
0.24
-0.15
-0.24
Sea level pressure was not recorded at the Lancing Municipal Airport weather station.
-------
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
11.4.1 Pearson Correlation Analysis
Table 11-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and selected meteorological parameters for the Indiana monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered about Pearson correlations for the Indiana sites:
• Some of the strongest correlations were exhibited at the Indiana monitoring sites,
indicating that meteorological conditions influence concentrations of the pollutants of
interest.
• The Indianapolis sites sampled for a limited duration during the 2006 program year.
A low number of measured detections, such as at WPIN, can skew the correlations in
one direction or another. A full year of sampling would provide a better indication of
correlations between concentrations and meteorological parameters.
• Correlations between formaldehyde and the temperature parameters were particularly
strong, indicating that as temperature increases, formaldehyde concentrations also
increase.
• The correlations with sea level pressure tended to be positive, correlations with scalar
wind speed were negative. This indicates that increasing pressure and decreasing
wind speeds correspond to increasing concentrations of the pollutants of interest.
11.4.2 Composite Back Trajectory Analysis
Figures 11-8 to 11-11 are composite back trajectory maps for the Indiana monitoring site
for the days on which sampling occurred. Each line represents the 24-hour trajectory along
which a parcel of air traveled toward the monitoring site on a sampling day. Each concentric
circle around the site in Figures 11-8 to 11-11 represents 100 miles.
The following observations can be made from Figures 11-8 through 11-11:
• Figure 11-8 shows that the 24-hour airshed domain is somewhat large at IDIN, with
trajectories originating greater than 700 miles away. Most of the trajectories
originated more than 300 miles from the site.
11-17
-------
Figure 11-8. Composite Back Trajectory Map for IDIN
00
-------
Figure 11-9. Composite Back Trajectory Map for INDEM
-------
Figure 11-10. Composite Back Trajectory Map for ININ
to
o
-------
Figure 11-11. Composite Back Trajectory for WPIN
-------
• Figure 11-9 shows that the 24-hour airshed domain is larger at the INDEM
monitoring site, with trajectories originating more than 800 miles away, although
most of the trajectories originate within 400 miles of the site.
• Figure 11-10 shows that none of the back trajectories for ININ originated to the
northeast, and very few to the southwest. The longest trajectory originated over
700 miles to the north-northwest, with most of the trajectories originating within
400 miles of the monitoring site.
• Figure 11-11 shows that no trajectories for the WPIN site originated to the north and
all the trajectories originated within 500 miles. However, sampling occurred on only
six days at WPIN. The composite back trajectory map for WPIN might look different
with a full year's worth of sampling.
11.4.3 Wind Rose Analysis
Hourly wind data from the Indianapolis International Airport near the IDIN, ININ and
WPIN monitoring sites and the Lancing Municipal Airport near the INDEM monitoring site
were uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces
a graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
about a 16-point compass, and uses different shading to represent wind speeds. Figures 11-12
through 11-15 are the wind roses for the Indiana monitoring sites on days that sampling
occurred.
Observations from Figure 11-12 for IDIN include:
• Hourly winds were predominantly out of the southeast and northwest (each 9 percent
of observations), closely followed by westerly winds (8 percent of observations.)
• Winds with a westerly component were more likely to reach speeds greater than
17 knots.
• Five percent of observations were calm (<2 knots).
Observations from Figure 11-13 for INDEM include:
• Hourly winds were predominantly out of the south (10 percent of observations) and
west (10 percent).
• Wind speeds frequently ranged from 7 to 11 knots on day samples were collected.
• Calm winds were observed for 21 percent of the measurements.
11-22
-------
Figure 11-12. Wind Rose for IDIN Sampling Days
•WESTl
to
WIND SPEED
(Knots)
| | 5=22
I I 17 - 21
• 11 - 17
I I -q- 7
^| 2- 4
Calms: 5.43%
-------
Figure 11-13. Wind Rose for INDEM Sampling Days
,---"" NORTH'---.
to
1 5%
SOUTH ----
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
^| 11 - 17
• 7- 11
I I A- 7
• 2- 4
Calms: 21.38%
-------
Figure 11-14. Wind Rose for ININ Sampling Days
to
-------
Figure 11-15. Wind Rose for WPIN Sampling Days
to
SOUTH .-'•
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
^| -11 - 17
^| 7- 11
I I 4- 7
• 2- 4
Calms: 2.82%
-------
Observations from Figure 11-14 for ININ include:
• Hourly winds were predominantly out of the west (11 percent of observations),
southeast (9 percent), and northwest (9 percent).
• Winds with a westerly component were more likely to reach speeds greater than
17 knots.
• Calm winds were recorded for 6 percent of observations.
Observations from Figure 11-15 for WPIN include:
• South-southwesterly to westerly winds were observed most frequently, accounting for
approximately 45 percent of observations. Northerly winds accounted for another 10
percent of observations.
• The most commonly observed wind speeds were in the range of 7-11 knots.
11.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could
not be performed as ERG did not analyze for VOCs for these sites. A mobile tracer analysis
could not be performed as these sites did not sample for SNMOC.
11.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Lake and Marion Counties, Indiana
were obtained from the Indiana Bureau of Motor Vehicles and the U.S. Census Bureau, and are
summarized in Table 11-6. Table 11-6 also includes a vehicle registration to county population
ratio (vehicles per person). In addition, the population within 10 miles of each site is presented.
An estimation of 10-mile vehicle registration was computed using the 10-mile population
surrounding the monitor and the vehicle registration ratio. Finally, Table 11-6 contains the
average daily traffic information, which represents the average number of vehicles passing the
monitoring sites on the nearest roadway to each site on a daily basis.
11-27
-------
Table 11-6. Motor Vehicle Information for the Indiana Monitoring Sites
Site
IDIN
INDEM
ININ
WPIN
2006 Estimated
County Population
865,504
494,202
865,504
865,504
Number of
Vehicles
Registered
897,388
453,146
897,388
897,388
Vehicles per Person
(Registration:
Population)
1.03
0.92
1.03
1.03
Population Within
10 Miles
591,305
404,985
660,891
792,104
Estimated 10 Mile
Vehicle Ownership
613,088
371,341
685,237
821,284
Traffic Data
(Daily
Average)
30,916
42,950
97,780
11,514
to
oo
-------
Observations gleaned from Table 11-6 include:
• Lake County, where INDEM is located, has roughly half the population and vehicle
registration of Marion County, but their vehicles per person ratios are similar.
• INDEM has the lowest 10-mile population and estimated vehicle ownership, while
WPIN has the most.
• WPIN has the lowest traffic volume, while ININ experiences the most.
• Compared to other UATMP sites, the sites located in Marion County are in the top
third of all sites for county population and vehicle registration, as well as 10 mile
population and vehicle ownership.
• ININ has the fifth largest daily traffic volume of all UATMP sites, yet INDEM falls
in the middle of the range in regards to population and vehicle registration.
11.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. Only
INDEM participated in the UATMP prior to 2005 and Figure 11-16 presents the trends analysis
for formaldehyde for INDEM.
Figure 11-16 shows that:
• Formaldehyde appears to have decreased slightly since 2005, but is still higher than in
2004. However, when considering the confidence interval, as shown by error bars in
Figure 11-16, the values have not changed considerably.
11.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Indiana sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 11-7.
Additionally, the pollutants of interest are bolded. The Indianapolis sites did not sample long
enough to calculate annual averages for the pollutants of interest. In addition to the annual
averages and risks based on 2006 monitoring data, where available, data from EPA's 1999
11-29
-------
Figure 11-16. Comparison of Yearly Averages for the INDEM Monitoring Site
90
80
70
! 60
a.
50
0)
o
o 40
O
d>
O)
ro
5 30
20
10
2004
2005
Year
2006
D Formaldehyde
-------
NATA were retrieved and are also presented in Table 11-7. The NATA data is presented for the
census tract where the monitoring site is located.
The census tract information for the Indiana sites is as follows:
• The census tract for IDIN is 18097342300, which had a population of 6,536 and
represents approximately 0.8 percent of the Marion County population in 2000.
• The census tract for ININ is 18097358100, which had a population of 3,374 and
represents approximately 0.4 percent of the Marion County population in 2000.
• The census tract for WPIN is 18097350700, which had a population of 2,058 and
represents approximately 0.2 percent of the Marion County population in 2000.
• The census tract for INDEM is 18089010202, which had a population of 1,689 and
represents approximately 0.3 percent of the Lake County population in 2000.
The following observations can be made from Table 11-7:
• Formaldehyde and acetaldehyde had the highest NATA-modeled concentrations of all
the pollutants of interest at the Indiana monitoring sites.
• Due to the short sampling duration of the Indianapolis sites, only INDEM has annual
averages.
• While the acetaldehyde annual average was somewhat similar to the NATA-modeled
concentration, the formaldehyde annual average was significantly higher than the
NATA-modeled concentration at INDEM. However, because formaldehyde has such
a low cancer risk, the annual average-based cancer risk was still less than 1 in-a-
million. The same was not true of noncancer risk. The annual average-based
noncancer HQ was 6.32 for INDEM, while the NATA-modeled noncancer HQ for
formaldehyde was 0.19.
• The highest NATA-modeled cancer risk at a UATMP site, based on census tract
location, was calculated for arsenic at ININ (208.16 in-a-million). This was more
than twice the next highest NATA-modeled cancer risk for a UATMP site
(dichloromethane, 71 in-a-million at MIMN). This risk near IDIN for arsenic is much
lower.
11.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 11-8 and 11-9 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
11-31
-------
Table 11-7. Chronic Risk Summary for the Monitoring Sites in Indiana
Pollutant
Cancer
URE
(Hg/rn3)
Noncancer
RfC
(Mg/m3)
1999 NATA
Modeled
Concentration
(Ug/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(Ug/m3)
Cancer
Risk
(in-a-
million)
Noncancer
Risk
(HQ)
Indianapolis, Indiana (IDIN) - Census Tract ID 18097342300
Acet aldehyde
Arsenic*
Cadmium*
Cobalt*
Formaldehyde
Manganese*
Nickel*
0.0000022
0.0043
0.0018
NR
5.5E-09
NR
0.00016
0.009
0.00003
0.00002
0.0001
0.0098
0.00005
0.000065
1.41
<0.01
0.01
0.01
1.74
0.01
O.01
3.10
4.74
0.05
NR
0.01
NR
0.06
0.16
0.04
0.01
0.01
0.18
0.08
0.01
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Gary, Indiana (INDEM) - Census Tract ID 18089010202
Acet aldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
1.96
1.86
4.32
0.01
0.22
0.19
4.63 ±0.56
61. 91 ±17.11
10.19
0.34
0.51
6.32
Indianapolis, Indiana (EVEN) - Census Tract ID 18097358100
Acet aldehyde
Arsenic*
Cadmium*
Cobalt*
Formaldehyde
Hexavalent Chromium
Manganese*
0.0000022
0.0043
0.0018
NR
5.5E-09
0.012
NR
0.009
0.00003
0.00002
0.0001
0.0098
0.0001
0.00005
1.64
0.05
O.01
O.01
1.92
0.01
0.01
3.60
208.16
0.08
NR
0.01
3.19
NR
0.18
1.61
O.01
O.01
0.20
0.01
0.13
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Washington Park, Indianapolis, Indiana (WPIN) - Census Tract ID 18097350700
Acet aldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
1.48
1.47
3.25
0.01
0.16
0.15
NA
NA
NA
NA
NA
NA
to
* Metals sampled with PM10 filters
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made
NA = annual average not available
-------
respectively. Table 11-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxi city-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 11-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. Because the Indianapolis sites have no annual averages and therefore no
site-specific cancer and noncancer risk calculations, the emissions for Marion County in
Tables 11-8 and 11-9 have been consolidated into one entry.
The following observations can be made from Table 11-8:
• Nine of the 10 highest emitted pollutants (by mass) with cancer risk factors were the
same for both Marion and Lake Counties.
• Benzene, formaldehyde, and acetaldehyde were the top three emitted pollutants in
both counties.
• The pollutants with the 10 highest cancer toxi city-weighted emissions were the same
in both counties. Coke oven emissions have the highest toxicity-weighted emissions
in both counties. Acetaldehyde was identified in all three "top 10" lists for Lake
County/INDEM.
The following observations can be made from Table 11-8:
• Nine of the 10 highest emitted pollutants with noncancer risk factors were the same
for both Marion and Lake Counties.
• Hydrochloric acid, toluene, xylenes, benzene, and methanol were the top five emitted
pollutants in both counties, although not necessarily in that order.
• Acrolein has the highest noncancer toxicity-weighted emissions in Marion County,
followed by manganese and hydrochloric acid.
• Unlike most other UATMP counties, manganese has the highest noncancer toxicity-
weighted emissions in Lake County.
11-33
-------
Table 11-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Indiana
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Indiana
Benzene
Formaldehyde
Acetaldehyde
Dichloromethane
1,3 -Butadiene
1 ,3 -Dichloropropene
Naphthalene
Coke Oven Emissions
Trichloroethylene
£>-Dichlorobenzene
762.79
312.54
129.03
123.14
102.02
62.42
46.08
30.48
21.28
13.81
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Cancer Risk
Pollutant (in-a-million)
polis, Indiana (IDIN, ININ, and WPIN) - Marion County
Coke Oven Emissions
Benzene
1,3 -Butadiene
Arsenic
Hexavalent Chromium
Naphthalene
Cadmium
Lead
Poly cyclic Organic Matter as 15 -PAH
Acetaldehyde
1.89E-02
5.95E-03
3.06E-03
2.75E-03
1.71E-03
1.57E-03
6.55E-04
5.50E-04
3.07E-04
2.84E-04
Gary, Indiana (INDEM) - Lake County
Benzene
Formaldehyde
Acetaldehyde
Coke Oven Emissions
Naphthalene
Dichloromethane
1,3 -Butadiene
1 ,3 -Dichloropropene
Lead
/>-Dichlorobenzene
410.05
195.91
147.88
104.05
51.13
47.36
41.45
35.16
22.20
7.78
Coke Oven Emissions
Arsenic
Benzene
Naphthalene
1,3 -Butadiene
Hexavalent Chromium
Lead
Poly cyclic Organic Matter as 15 -PAH
Acetaldehyde
Cadmium
6.45E-02
3.96E-03
3.20E-03
1.74E-03
1.24E-03
1.15E-03
6.12E-04
3.88E-04
3.25E-04
2.67E-04
Acetaldehyde 10.19
Formaldehyde 0.34
-------
Table 11-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Indiana
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Noncancer
Risk
Pollutant (HQ)
Indianapolis, Indiana (ID IN, ININ, and WPIN) - Marion County
Toluene
Xylenes
Hydrochloric Acid
Benzene
Methanol
Methyl Ethyl Ketone
Hexane
Formaldehyde
Ethylbenzene
Methyl Isobutyl Ketone
2,162.01
1,373.12
1,062.57
762.79
403.50
362.07
334.41
312.54
301.76
254.05
Acrolein
Manganese
Hydrochloric Acid
1,3 -Butadiene
Formaldehyde
Benzene
Arsenic
Bromomethane
Cadmium
Nickel
1,047,145.40
112,123.36
53,128.59
51,009.39
31,891.65
25,426.35
21,325.21
18,967.01
18,188.33
16,949.04
Gary, Indiana (INDEM) - Lake County
Hydrochloric Acid
Toluene
Xylenes
Benzene
Methanol
Hexane
Formaldehyde
Methyl Ethyl Ketone
Acetaldehyde
Ethylbenzene
1,133.24
1,000.22
703.65
410.05
243.60
232.53
195.91
184.87
147.88
125.17
Manganese
Acrolein
Hydrochloric Acid
Arsenic
Nickel
1,3 -Butadiene
Formaldehyde
Chlorine
Naphthalene
Acetaldehyde
813,675.39
492,627.56
56,662.03
30,703.29
25,638.09
20,724.19
19,990.77
19,571.26
17,042.50
16,431.15
Formaldehyde 6.32
Acetaldehyde 0.51
-------
Formaldehyde has an annual average-based noncancer HQ greater than 1 in Lake County
(6.32), and was one of only two UATMP site-formaldehyde noncancer risks to be greater than 1
(the other was SPIL, 1.40).
Indiana Pollutant Summary
• The pollutants of interest vary by location at the Indiana sites, but acetaldehyde and
formaldehyde were pollutants of interest at each site.
• Formaldehyde had the highest daily average concentration at each site and was
particularly high at INDEM.
• Formaldehyde exceeded both of the acute risk factors and the intermediate risk factor at
INDEM.
11-36
-------
12.0 Site in Kentucky
This section presents meteorological, concentration, and spatial trends for the UATMP
site located in Hazard, Kentucky (HAKY). Figure 12-1 is a topographical map showing the
monitoring site in its rural location. Figure 12-2 identifies point source emission locations within
10 miles of this site that reported to the 2002 NEI for point sources. HAKY is located near a
very small number of point sources, located mainly to the north and southeast of the site. The
town of Hazard is located in southeast Kentucky, just on the outskirts of Daniel Boone National
Forest. The area experiences all four seasons, and precipitation is fairly evenly distributed
throughout the year (http://www.wildernet.com/pages/area.cfm?areaID=0802&CU_ID-l).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the HAKY monitoring site is at Julian Carroll Airport in Jackson, Kentucky (WBAN 03889).
Table 12-1 presents the average meteorological conditions of temperature (average maximum
and average), moisture (average dew point temperature, average wet-bulb temperature, and
average relative humidity), pressure (average sea level pressure), and wind information (average
scalar wind speed) for the entire year and on days samples were collected. Also included in
Table 12-1 is the 95 percent confidence interval. As shown in Table 12-1, average
meteorological conditions on sampling days were fairly representative of average weather
conditions throughout the year.
12.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Kentucky
monitoring site. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
12-1
-------
Figure 12-1. Hazard, Kentucky (HAKY) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
12-2
-------
Figure 12-2. Facilities Located Within 10 Miles of HAKY
Breath itt
County
Perry
County
Leslie
Coynty
Knott
County
Note: Due to facility density attd collocattort. the total faeMies
displayed may not represent all facilities within the area of interest.
Legend
"&• HAKY UATMP site
• 10 mile radius
I County boundary
Source Category Group (No. of Facilities)
F Fuel Combustion Industrial Facility (1)
s Lumber & Wood Products Facility (1)
P Miscellaneous Processes Industrial Facility (2)
' Waste Treatment & Disposal Industrial Facility (1)
* Wood Furniture Facility (1)
12-3
-------
Table 12-1. Average Meteorological Conditions near the Monitoring Site in Kentucky
Site
HAKY
WBAN
03889
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
66.48
±1.61
67.38
±3.61
Average
Temperature
(»F)
57.36
±1.53
58.14
±3.39
Average
Dew Point
Temperature
(°F)
44.36
±1.72
45.93
±3.48
Average
Wet Bulb
Temperature
(°F)
50.89
±1.45
51.83
±3.03
Average
Relative
Humidity
(%)
65.34
±1.58
67.53
±3.99
Average
Sea Level
Pressure
(mb)
1017.23
±0.63
1016.39
±1.42
Average
Scalar Wind
Speed
(kt)
2.76
±0.20
2.89
±0.52
to
-------
to the top 95 percent of the site's total failed screens. Only hexavalent chromium was sampled at
HAKY, and it did not fail any screens as shown in Table 12-2. In order to facilitate analysis, this
pollutant will be considered HAKY's only pollutant of interest.
Table 12-2. Comparison of Measured Concentrations and EPA Screening Values
for the Kentucky Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Hazard, Kentucky - HAKY
Hexavalent Chromium
0
44
0
0
0
12.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 12-3. Annual averages are presented and discussed in further detail in later
sections.
The following observations are shown in Table 12-3:
• The daily average concentration for hexavalent chromium at HAKY was 0.020 ±
0.004 ng/m3.
• The seasonal averages varied little across the seasons.
• The autumn average concentration was not calculated due to the low number of
measured detections.
12-5
-------
Table 12-3. Daily and Seasonal Averages for the Pollutants of Interest for the Kentucky Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
Hazard, Kentucky - HAKY
Hexavalent Chromium
44
59
0.020
0.004
0.011
0.004
0.017
0.004
0.026
0.009
NR
NR
NR = Not reportable due to low number of measured detections.
Daily
to
-------
12.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for HAKY was evaluated using ATSDR
short-term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is
defined as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15
to 364 days. Its is useful to compare the preprocessed daily measurement to the short-term MRL
and REL factors, as well as compare the seasonal averages to the intermediate MRL. Acute risk
factors are not available for hexavalent chromium; therefore, acute risk cannot be evaluated. The
intermediate risk value was not exceeded in the samples collected at HAKY.
12.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
12.4.1 Pearson Correlation Analysis
Table 12-4 presents the summary of Pearson correlation coefficients for hexavalent
chromium and select meteorological parameters at the HAKY monitoring site. (Please refer to
Section 3.1.6 for more information on Pearson correlations.) The correlations calculated
between hexavalent chromium and the meteorological parameters at HAKY were weak.
12.4.2 Composite Back Trajectory Analysis
Figure 12-3 is a composite back trajectory map for the HAKY monitoring site for the
days on which sampling occurred. Each line represents the 24-hour trajectory along which a
parcel of air traveled toward the monitoring site on a sampling day. Each concentric circle
around the site in Figure 12-3 represents 100 miles.
The following observations can be made from Figure 12-3:
• Back traj ectories originated from a variety of directions at HAKY.
12-7
-------
Table 12-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Kentucky
Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Hazard, Kentucky - HAKY
Hexavalent Chromium
44
0.36
0.32
0.35
0.36
0.07
0.14
-0.23
to
00
-------
Figure 12-3. Composite Back Trajectory Map for HAKY
;
i
i
i
i
i
i
V
I
1
1
1
I
^
-*
\
-------
The 24-hour airshed domain was moderately large at HAKY, with trajectories
originating as far away as Louisiana and Wisconsin (> 600 miles).
However, the majority of the trajectories originated from within 300 miles of the site.
12.4.3 Wind Rose Analysis
Hourly wind data from the Julian Carroll Airport near the HAKY monitoring site were
uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces a
graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
about a 16-point compass, and uses different shading to represent wind speeds. Figure 12-4 is
the wind rose for the HAKY monitoring site on days that sampling occurred.
Observations from Figure 12-4 include:
• Hourly winds were predominantly out of the west (7 percent of observations), south
(6 percent), and south-southwest (6 percent) on sampling days.
• Winds near HAKY were light, as calm winds (<2 knots) were the most frequently
observed wind speed (54 percent of observations).
12.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could
not be performed as ERG did not analyze for VOCs at this site. A mobile tracer analysis could
not be performed as this site did not sample for SNMOC.
12.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population were obtained from the Kentucky
Department of Revenue and Regulation and the U.S. Census Bureau, as shown in Table 12-5.
Table 12-5 also includes a vehicle registration to county population ratio (vehicles per person)
for Perry County. In addition, the population within 10 miles of each site is presented. An
estimate of 10-mile vehicle registration was computed using the 10-mile population surrounding
the monitors and the vehicle registration ratio. Finally, Table 12-5 contains the average daily
12-10
-------
Figure 12-4. Wind Rose for HAKY Sampling Days
SOUTH ,-'
WIND SPEED
(Knots)
| | 5=22
I I 17 - 21
• 11 - 17
CZI 7- 11
I I -q- 7
^| 2- 4
Calms: S.85%
-------
Table 12-5. Motor Vehicle Information for the Kentucky Monitoring Site
Site
HAKY
2006 Estimated
County Population
29,753
Number of
Vehicles
Registered
22,704
Vehicles per Person
(Registration:
Population)
0.76
Population Within
10 Miles
32,103
Estimated 10 Mile
Vehicle
Ownership
24,497
Traffic Data
(Daily Average)
500
to
to
-------
traffic information, which represents the average number of vehicles passing the monitoring sites
on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 12-5 include:
• HAKY's county population, vehicle registration, population and vehicle ownership
within 10 miles, and daily traffic volume are some of the lowest compared to other
UATMP sites.
• HAKY is located in a rural area.
12.6 Trends Analysis
A trends analysis could not be performed for HAKY as this site has not participated in
the UATMP for three consecutive years.
12.7 Chronic Risk Analysis
A chronic risk analysis was completed hexavalent chromium at HAKY. Annual
averages, theoretical cancer and noncancer risk, cancer UREs and/or noncancer RfCs are
presented in Table 12-6. Finally, data from EPA's 1999 NATA for hexavalent chromium were
retrieved and are presented in Table 12-6. The NATA data is presented for the census tract where
the monitoring site is located.
The census tract information for HAKY is as follows:
• The HAKY monitoring site is located in census tract 21193970400.
• The population for the census tract where the HAKY monitoring site is located was
4,359, which represents fifteen percent of Perry County's population in 2000.
The following observations can be made from Table 12-6:
• Both the NATA-modeled and annual average concentration for hexavalent chromium
were less than 0.01 |ig/m3.
• In terms of cancer risk, the NATA-modeled and calculated cancer risks were both less
than 1 in-a-million, although the annual average-based cancer risk (0.20 in-a-million) was
an order of magnitude greater than the NATA-modeled cancer risk (0.03 in-a-million).
12-13
-------
Table 12-6. Chronic Risk Summary for the Monitoring Site in Kentucky
Pollutant
Cancer
URE
(Hg/rn3)
Noncancer
RfC
(Mg/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual Average
(Hg/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk
(HQ)
Hazard, Kentucky (HAKY) - Census Tract ID 21193970400
Hexavalent Chromium
0.012
0.0001
0.01
0.03
0.01
0.01 ±0.01
0.20
0.01
to
-------
• Both noncancer hazard quotients were less than 0.01, suggesting very little risk for
noncancer health affects due to hexavalent chromium.
12.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 12-7 and 12-8 present a risk-
based assessment of the county-level emissions based on cancer and noncancer toxicity,
respectively. Table 12-7 presents the 10 pollutants with the highest emissions from the 2002 NEI,
the 10 pollutants with the highest toxicity-weighted emissions, and the hexavalent chromium cancer
risk (in-a-million) as calculated from the annual average. Table 12-8 presents similar information,
but identifies the 10 pollutants with the highest noncancer risk (HQ) as calculated from the annual
average. The pollutants in these tables are limited to those that have cancer and noncancer risk
factors, respectively. As a result, the highest emitted pollutants in the cancer table may not be the
same as the noncancer table, although the actual value of the emissions will be.
The following observations can be made from Table 12-7:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor and had the
highest cancer toxicity-weighted emissions for Perry County, Kentucky.
• Eight of 10 pollutants (benzene, acetaldehyde, tetrachloroethylene, 1,3-butadiene,
naphthalene, />-dichlorobenzene, POM as 15-PAH, and POM as 7-PAH) appeared on
both the highest emitted list and the highest cancer toxicity-weighted emissions list,
indicating that most of the highest emitted pollutants were also the most toxic.
• Perry County has low HAP emissions among the UATMP counties.
• Hexavalent chromium, the only pollutant sampled at HAKY, had a low cancer risk based
its annual average (0.20 in-a-million). This pollutant does not appear on either the
highest emissions list or the highest cancer toxicity-weighted emissions list.
The following observations can be made from Table 12-8:
• Toluene was the highest emitted pollutant with noncancer risk factor in Perry County.
• Unlike most other UATMP counties, toluene did rank in the top 10 pollutants based on
toxicity-weighted emissions (tenth highest).
• Acrolein had the highest noncancer toxicity-weighted emissions, but did not appear in the
list of highest emitted pollutants.
12-15
-------
Table 12-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for HAKY
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(for Perry County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Perry County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for HAKY)
Cancer Risk
Pollutant (in-a-million)
Hazard, Kentucky - HAKY
Benzene
Formaldehyde
Tetrachloroethylene
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Naphthalene
Poly cyclic Organic Matter as 15 -PAH
£>-Dichlorobenzene
Polycyclic Organic Matter as 7-PAH
38.73
11.03
3.87
3.67
2.50
2.40
1.23
0.85
0.63
0.15
Benzene
1,3 -Butadiene
Lead
Polycyclic Organic Matter as 15 -PAH
Naphthalene
Polycyclic Organic Matter as 7-PAH
Polycyclic Organic Matter as no n- 15 -PAH
Tetrachloroethylene
Acetaldehyde
/>-Dichlorobenzene
3.02E-04
7.51E-05
5.70E-05
4.68E-05
4.19E-05
3.02E-05
2.64E-05
2.29E-05
8.08E-06
6.92E-06
Hexavalent Chromium 0.20
to
-------
Table 12-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for HAKY
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Perry County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Perry County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for HAKY)
Noncancer
Risk
Pollutant (HQ)
Hazard, Kentucky - HAKY
Toluene
Xylenes
Benzene
Methanol
Methyl Tert-Butyl Ether
Formaldehyde
Ethylbenzene
Hexane
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
68.21
45.74
38.73
14.82
11.56
11.03
10.51
10.42
8.20
5.10
Acrolein
Benzene
4,4'-MethylenediphenylDiisocyanate
1,3 -Butadiene
Formaldehyde
Cyanide
Xylenes
Naphthalene
Acetaldehyde
Toluene
43,070.00
1,290.98
1,255.09
1,252.34
1,125.93
986.23
457.40
410.44
407.88
170.52
Hexavalent Chromium <0.01
to
-------
Hexavalent chromium did not rank in the top 10 highest emitted pollutants with
noncancer risk factors or the 10 highest noncancer toxicity-weighted emissions in Perry
County.
Kentucky Pollutant Summary
• While hexavalent chromium, the only pollutant sampled for at HAKY, did not fail any
screens, it was treated as a pollutant of interest in order to facilitate analysis.
12-18
-------
13.0 Site in Massachusetts
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Massachusetts (BOMA). This site is located in the Boston-Lawrence-Worcester MSA.
Figure 13-1 is a topographical map showing the monitoring site in its urban location. Figure 13-
2 identifies point source emission locations within 10 miles of this site that reported to the 2002
NEI for point sources. BOMA is located near a number of sources, of which a majority of the
facilities employ fuel combustion processes.
Boston's location on the East Coast ensures that the city experiences a fairly active
weather pattern. Most storm systems track across the Northeast, bringing ample precipitation to
the area. The proximity to the Atlantic Ocean helps moderate temperature, both in the summer
and the winter, while at the same time allowing winds to gust higher than they would farther
inland. Winds generally flow from the northwest in the winter and southwest in the summer
(Ruffner and Bair, 1987).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the BOMA monitoring site is at Logan International Airport (WBAN 14739). Table 13-1
presents the average meteorological conditions of temperature (average maximum and average),
moisture (average dew point temperature, average wet-bulb temperature, and average relative
humidity), pressure (average sea level pressure), and wind speed information (average scalar
wind speed) for the entire year and on days samples were collected. Also included in Table 13-1
is the 95 percent confidence interval. As shown in Table 13-1, average meteorological
conditions on sampling days were fairly representative of average weather conditions throughout
the year.
13.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Massachusetts
monitoring site. As described in Section 3.1.4, the methodology for evaluating pollutants of
13-1
-------
Figure 13-1. Boston, Massachusetts (BOMA) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
13-2
-------
Figure 13-2. Facilities Located Within 10 Miles of BOMA
Note; Due to facility density and collocation, the total facilities
dtspfayeci may not represent aU facilities within the area of interest.
Legend
lV BOMAUATMPsite
10 mile radius
[ | County boundary
Source Category Group (No. of Facilities)
c Chemicals & Allied Products Facility f3}
s Educational Services Facility (1)
D Fabricated Metal Products Facility (1)
F Fuel Combustion Industrial Facility (82)
I Incineration Industrial Facility (1)
J Industrial Machinery & Equipment Facility (3)
= Instruments & Related Products Facility (1)
»- Integrated Iron & Steel Manufacturing Facility (1)
L Liquids Distribution Industrial Facility (9)
P Miscellaneous Processes Industrial Facility (6)
\ Non-ferrous Metals Processing Industrial Facility (1)
u stone, Clay, Glass, & Concrete Products (3)
e Utility Boilers (5)
v Waste Treatment & Disposal Industrial Facility (12)
r Wholesale Trade {1)
13-3
-------
Table 13-1. Average Meteorological Conditions near the Monitoring Site in Massachusetts
Site
BOMA
WBAN
14739
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
59.96
±1.69
59.49
±4.04
Average
Temperature
(»F)
53.03
±1.59
52.92
±3.71
Average
Dew Point
Temperature
(°F)
41.07
±1.80
41.68
±4.15
Average
Wet Bulb
Temperature
(°F)
47.55
±1.50
47.70
±3.51
Average
Relative
Humidity
(%)
66.49
±1.58
67.98
±3.53
Average
Sea Level
Pressure
(mb)
1014.72
±0.80
1015.44
±1.92
Average
Scalar
Wind Speed
(kt)
9.60
±0.32
9.13
±0.72
-------
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. BOMA sampled for metals and hexavalent
chromium only. Table 13-2 presents the pollutants that failed at least one screen at BOMA
The following observations are shown in Table 13-2:
• A total of 93 measured concentrations failed screens.
• The screening process for BOMA resulted in five pollutants of interest: arsenic (48),
nickel (25), manganese (9), and hexavalent chromium (8).
• The percent of measured detections failing screens ranged from five percent
(cadmium) to 86 percent (arsenic).
Table 13-2. Comparison of Measured Concentrations and EPA Screening Values
for the Massachusetts Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Boston, Massachusetts - BOMA
Arsenic (PM10)
Nickel (PM10)
Manganese (PM10)
Hexavalent Chromium
Cadmium (PM10)
Total
48
25
9
8
3
93
56
56
56
54
56
278
85.71
44.64
16.07
14.81
5.36
33.45
51.61
26.88
9.68
8.60
3.23
51.61
78.49
88.17
96.77
100.00
13.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there are at least seven measured detections within
each season, then a seasonal average can be calculated. The seasonal average includes 1/2
MDLs substituted for all non-detects. A seasonal average was not calculated for pollutants with
less than seven measured detections in a respective season. Finally, the annual average is the
13-5
-------
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 13-3. Annual averages are presented and discussed in further detail in later
sections.
The following observations are shown in Table 13-3:
• Among the daily averages for BOMA, manganese had the highest concentration by
mass (3.67 ± 0.46 ng/m3), followed by nickel (2.39 ± 0.35 ng/m3).
• The other two pollutants were at least an order of magnitude less than these two
pollutants.
• The seasonal averages of nickel appeared to vary the most, but the difference was not
statistically significant.
13.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for BOMA was evaluated using ATSDR
acute and intermediate MRL and California EPA acute REL factors. Acute risk is defined as
exposures from 1 to 14 days while intermediate risk is defined as exposures from 15 to 364 days.
It is useful to compare the preprocessed daily measurement to the short-term MRL and REL
factors, as well as compare the seasonal averages to the intermediate MRL. Of the five
pollutants with at least one failed screen, none exceeded either the acute or intermediate risk
values.
13.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
13-6
-------
Table 13-3. Daily and Seasonal Averages for the Pollutants of Interest for the Massachusetts Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
Boston, Massachusetts - BOMA
Arsenic (PM10)
Hexavalent Chromium
Manganese (PM10)
Nickel (PM10)
56
54
56
56
56
61
56
56
0.55
0.06
3.67
2.39
0.11
0.01
0.46
0.35
0.50
0.04
3.63
3.43
0.16
0.02
0.85
0.82
0.49
0.05
3.93
2.38
0.17
0.02
1.06
0.59
0.73
0.06
3.12
1.49
0.37
0.02
0.77
0.21
0.53
0.05
3.86
1.89
0.15
0.04
0.79
0.32
-------
13.4.1 Pearson Correlation Analysis
Table 13-4 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the BOMA monitoring site.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered from Table 13-4:
• Most of the correlations were weak.
• Nickel exhibited a strong negative correlation with average temperature, indicating
that nickel concentrations tend to decrease with increasing temperature.
• Arsenic exhibited a strong negative correlation with scalar wind speed, which
indicates that increasing wind speeds result in decreasing arsenic concentrations.
• All of the correlations with scalar wind speed were negative, which indicates that
increasing wind speeds result in decreasing concentrations of the pollutants of
interest.
13.4.2 Composite Back Trajectory Analysis
Figure 13-3 is a composite back trajectory map for the BOMA monitoring site for the
days on which sampling occurred. Each line represents the 24-hour trajectory along which a
parcel of air traveled toward the monitoring site on a sampling day. Each concentric circle
around the site in Figure 13-3 represents 100 miles.
The following observations can be made from Figure 13-3:
• Back trajectories originated from a variety of directions at BOMA.
• The 24-hour airshed domain was large at BOMA, with trajectories originating as far
away as the Northern Quebec, Canada (> 700 miles).
• 63 percent of the trajectories originated within 400 miles of the site.
13.4.3 Wind Rose Analysis
Hourly wind data from the Logan International Airport near the BOMA monitoring site
were uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces
a graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
13-8
-------
Table 13-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Massachusetts Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Boston, Massachusetts - BOMA
Arsenic (PM10)
Hexavalent Chromium
Manganese (PM10)
Nickel (PM10)
56
54
56
56
0.34
0.06
0.12
-0.47
0.27
0.09
0.03
-0.51
0.28
0.18
-0.10
-0.43
0.28
0.14
-0.04
-0.49
0.10
0.29
-0.33
0.04
0.11
0.02
0.26
0.33
-0.50
-0.16
-0.34
-0.38
-------
Figure 13-3. Composite Back Trajectory Map for BOMA
-------
about a 16-point compass, and uses different shading to represent wind speeds. Figure 13-4 is
the wind rose for the BOMA monitoring site on days that sampling occurred.
Observations from Figure 13-4 include:
• Hourly winds were predominantly out of the west (12 percent of observations), south-
southwest (12 percent), and southwest (11 percent) on sampling days.
• Winds tended to be breezier at BOMA than other UATMP sites.
• Wind speeds ranged from 7 to 11 knots for 47 percent of observations, and ranged
from 11 to 17 knots for 23 percent of observations.
• Calm winds (<2 knots) were recorded for only 3 percent of the observations.
13.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could
not be performed as this site did not sample for VOC. A mobile tracer analysis could not be
performed as this site did not sample for SNMOC.
13.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration was not available in Suffolk County, MA. Thus, state-
level vehicle registration from the Energy Information Administration (EIA) was allocated to the
county-level using the county-level population proportion. County-level population information
was obtained from the U.S. Census Bureau, and is summarized in Table 13-5. Table 13-5 also
includes a vehicle registration to county population ratio (vehicles per person). In addition, the
population within 10 miles of each site is presented. An estimate of 10-mile vehicle registration
was computed using the 10-mile population surrounding the monitors and the vehicle registration
ratio. Finally, Table 13-5 contains the average daily traffic information, which represents the
average number of vehicles passing the monitoring sites on the nearest roadway to each site on a
daily basis.
13-11
-------
Figure 13-4. Wind Rose for BOMA Sampling Days
SOUTH .--
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
^| 11 - 17
^| 7- 11
I I 4- 7
• 2- 4
Calms: 2.37%
-------
Table 13-5. Motor Vehicle Information for the Massachusetts Monitoring Site
Site
BOMA
2006 Estimated
County Population
687,610
Number of
Vehicles
Registered
424,907
Vehicles per Person
(Registration:
Population)
0.62
Population Within
10 Miles
1,562,639
Estimated 10 mile
Vehicle
Ownership
965,629
Traffic Data
(Daily Average)
27,287
-------
Observations gleaned from Table 13-5 include:
• Compared to other UATMP sites, BOMA's county population is in the middle of the
range.
• BOMA's 10-mile population is comparatively high, behind only sites in the New
York City, Philadelphia, Washington, D.C., and Chicago areas. As a result, its
estimated 10-mile vehicle ownership is also on the high end compared to other
UATMP sites, even though the estimated county-level vehicle ownership is in the
middle of the range for UATMP sites.
13.6 Trends Analysis
A trends analysis could not be performed for BOMA because this site does not sample
VOC or carbonyl compounds.
13.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
BOMA and where the annual average concentrations could be calculated (refer to Section 3.3.5
regarding the definition of an annual average). Annual averages, theoretical cancer and
noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 13-6. Additionally,
the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA for the pollutants
that failed at least one screen at BOMA were retrieved and are presented in Table 13-6. The
NATA data is presented for the census tract where the monitoring site is located.
The census tract information for BOMA is as follows:
• The BOMA monitoring site is located in census tract 25025080400.
• The population for the census tract where the BOMA monitoring site is located was
723, which represents 0.1 percent of Suffolk County's population in 2000.
The following observations can be made for hexavalent chromium from Table 13-6:
• Both the NATA-modeled and annual average concentration for hexavalent chromium
were less than 0.01 |ig/m3.
• In terms of cancer risk, the NATA-modeled and calculated cancer risks were very
similar (0.54 and 0.61 in-a-million, respectively).
13-14
-------
Table 13-6. Chronic Risk Summary for the Monitoring Site in Massachusetts
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer
Risk (in-
a-million)
Noncancer
Risk
(HQ)
Boston, Massachusetts (BOMA) - Census Tract ID 25025080400
Arsenic*
Cadmium*
Hexavalent Chromium
Manganese*
Nickel*
0.0043
0.0018
0.012
NR
0.00016
0.00003
0.00002
0.0001
0.00005
0.000065
0.07
0.03
<0.01
0.11
0.61
0.28
0.05
0.54
NR
0.10
<0.01
0.01
O.01
0.01
0.01
O.OliO.Ol
0.01 ±0.01
O.OliO.Ol
0.01 ±0.01
O.OliO.Ol
2.37
0.44
0.61
NR
0.38
0.02
0.01
O.01
0.07
0.04
* Metals sampled with PM10 filters
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made
-------
• Both noncancer hazard quotients for hexavalent chromium were less than 0.01,
suggesting very little risk for noncancer health affects due to hexavalent chromium.
The following observations can be made for metals from Table 13-6:
• The annual averages tended to be lower than the NATA-modeled concentrations,
especially for nickel.
• The cancer risks based on the 2006 annual average were higher than the NATA-
modeled cancer risks.
• Manganese has no cancer risk factor, so cancer risk cannot be assessed at this time.
• Noncancer risk for all of the metal pollutants of interest was very low for both the
NATA and 2006 annual average based noncancer risks.
13.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 13-7 and 13-8 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 13-7 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 13-8 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer table, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer and noncancer risk based on each site's annual average is limited to those pollutants for
which each respective site sampled. In addition, the highest cancer and noncancer risks based on
annual averages are limited to those pollutants failing at least one screen.
The following observations can be made from Table 13-7:
• Unlike most UATMP counties, benzene was not the highest emitted pollutant (by
mass) with a cancer risk factor in Suffolk County; formaldehyde was the most
emitted pollutant.
13-16
-------
Table 13-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for BOMA
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(for Suffolk County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Suffolk County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for BOMA)
Pollutant
Cancer Risk
(in-a-million)
Boston, Massachusetts - BOMA
Formaldehyde
Benzene
Acetaldehyde
Dichloromethane
1,3 -Butadiene
Tetrachloroethylene
Naphthalene
Polycyclic Organic Matter as 7-PAH
Trichloroethylene
Polycyclic Organic Matter as 15 -PAH
493.41
312.92
209.31
57.44
41.34
24.91
12.90
8.62
6.94
6.51
Benzene
1,3 -Butadiene
Polycyclic Organic Matter as 7-PAH
Acetaldehyde
Naphthalene
Polycyclic Organic Matter as 15 -PAH
Lead
Arsenic
Tetrachloroethylene
Nickel
2.44E-03
1.24E-03
7.43E-04
4.60E-04
4.39E-04
3.58E-04
1.83E-04
1.52E-04
1.47E-04
1.47E-04
Arsenic
Hexavalent Chromium
Cadmium
Nickel
2.37
0.61
0.44
0.38
-------
Table 13-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for BOMA
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Suffolk County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Suffolk County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for BOMA)
Pollutant
Noncancer
Risk
(HQ)
Boston, Massachusetts - BOMA
Toluene
Methyl 7er/-Butyl Ether
Xylenes
Formaldehyde
Methanol
Benzene
Methyl Ethyl Ketone
Acetaldehyde
Methyl Isobutyl Ketone
Ethylene Glycol
750.68
620.16
586.59
493.41
401.06
312.92
210.80
209.31
146.16
123.10
Acrolein
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Nickel
Benzene
Cyanide
Xylenes
Naphthalene
Glycol Ethers
940,325.73
50,347.56
23,257.08
20,668.04
14,092.82
10,430.69
8,719.15
5,865.88
4,299.58
2,624.15
Manganese
Nickel
Arsenic
Cadmium
Hexavalent Chromium
0.07
0.04
0.02
0.01
0.01
oo
-------
• Benzene did have the highest cancer toxicity-weighted emissions.
• Neither hexavalent chromium nor metals were among the highest emitted pollutants
in Suffolk County.
• Lead, arsenic, and nickel had some of the highest cancer toxicity-weighted emissions.
• Only arsenic had an annual average-based cancer risk greater than 1 in-a-million
(2.37).
The following observations can be made from Table 13-8:
• Although toluene was the highest emitted pollutant with a noncancer risk factor, it did
not rank in the top 10 pollutants based on toxicity-weighted emissions.
• Acrolein had the highest noncancer toxicity-weighted emissions, but did not appear in
the list of highest emitted pollutants.
• Nickel was the only pollutant that failed screens at BOMA and had one of the top 10
highest noncancer toxicity-weighted emissions.
• The noncancer HQ for nickel based on the annual average at BOMA was very low
(0.04).
Massachusetts Pollutant Summary
• The pollutants of interest at the Massachusetts site were arsenic, manganese, nickel, and
hexavalent chromium.
• Manganese had the highest daily average at BOMA.
• None of the pollutants of interest exceeded the acute or intermediate risk factors.
13-19
-------
14.0 Sites in Michigan
This section presents meteorological, concentration, and spatial trends for the two
UATMP sites in Michigan. The DEMI site is located in the Detroit area, while the ITCMI site is
in Sault Saint Marie on the Upper Peninsula. Figures 14-1 and 14-2 are topographical maps
showing the monitoring sites in their urban locations. Figures 14-3 and 14-4 identify point
source emission locations within 10 miles of the sites that reported to the 2002 NEI for point
sources. A number of point sources surround DEMI, several of which are located just south of
the site. Most of these point sources are involved in fuel combustion or waste treatment and
disposal processes. All of the industrial facilities within 10 miles of ITCMI are involved in
waste treatment and disposal.
The Detroit area is located in the Great Lakes region, where storm systems frequently
track across the region. Winters tend to be cold and wet, while summers are generally mild. The
urbanization of the area along with Lake St. Clair to the east are two major influences on the
city's weather. The lake tends to keep Detroit warmer in the winter and cooler in the summer
than more inland areas. The urban heat island keeps the city warmer than outlying areas. Winds
are often breezy and generally flow from the southwest on average. Sault Saint Marie is located
on the northeast edge of Michigan's Upper Peninsula. While this area also experiences an active
weather pattern, its climate is somewhat tempered by the surrounding waters of Lakes Superior
and Huron, as the city resides on the channel between the two lakes. This location experiences
ample precipitation, especially during lake-effect snow events (Ruffner and Bair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather stations closest
to the Michigan monitoring sites are Detroit-Metropolitan Airport and Sault Ste. Marie
International Airport, WBAN 94847 and 14847, respectively.
14-1
-------
Figure 14-1. Detroit, Michigan (DEMI) Monitoring Site
•• j?".-::vV^ \ v vrV-. •,>,' /-'•• ^,"v*;^
-Mfi^^l} • %^U-
^^: Wi^^vivv'^i
>W' •-':'. ,,v %. ^ :-\.^T^ i ^:- "- ''"'-*
' r~ •" * % -,?- "'^-« y>"J ...
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
14-2
-------
Figure 14-2. Sault Saint Marie, Michigan (ITCMI) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
14-2
-------
Figure 14-3. Facilities Located Within 10 Miles of DEMI
Legend
•&• DEM! UATMP site
Source Category Group (No. of Facilities)
* Automotive Repair, Services. & Parking (1 )
c Chemicals & Allied Products Facility (2)
z Electrical & Electronic Equipment Facility (1 )
D Fabricated Metal Products Facility (5)
K Ferrous Metals Processing Industrial Facility (1)
F Fuel Combustion Industrial Facility (33)
I Incineration Industrial Facility (5)
«• Integrated Iron & Steel Manufacturing Facility (2)
L Liquids Distribution Industrial Facility (8)
B Mineral Products Processing Industrial Facility (6)
P Miscellaneous Processes Industrial Facility (5)
v Non-ferrous Metals Processing Industrial Facility (1)
Note; Due to facility density and collocation, the total facilities
displayed may not represent al facilities wthin the area of interest
10 mile radius | | County boundary
2 Nonmetallic Minerals. Except Fuels (2)
P Petroleum/Nat Gas Prod. & Refining Industrial Facility (2)
> PharmaceLitical Production Processes Industrial Facility (1)
V Polymers & Resins Production Industrial Facility (2)
4 Production of Organic Chemicals Industrial Facility (2)
Y Rubber & Miscellaneous Plastic Products Facility (1)
u Stone, Clay, Glass, & Concrete Products (2)
s Surface Coating Processes Industrial Facility (3)
T Transportation Equipment {1)
s Utility Boilers (7)
1 Waste Treatment & Disposal Industrial Facility (14)
t Wholesale Trade (1)
14-4
-------
Figure 14-4. Facilities Located Within 10 Miles of ITCMI
Mote: Doe to facility density and collocation, the total facilities
displayed may not represent 3(1 faculties within the area of interest
Legend
TJT ITCMI UATMP site
10 mile radius
County boundary
Source Category Group {No. of Facilities)
i Waste Treatment & Disposal Industrial Facility (27)
14-5
-------
Table 14-1 presents the average meteorological conditions of temperature (average
maximum and average), moisture (average dew point temperature, average wet-bulb
temperature, and average relative humidity), pressure (average seal level pressure), and wind
information (average scalar wind speed) for the entire year and on days samples were collected.
Also included in Table 14-1 is the 95 percent confidence interval for each parameter. As shown
in Table 14-1, average meteorological conditions on sampling days were fairly representative of
average weather conditions throughout the year at both DEMI and ITCMI.
14.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Michigan
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. DEMI sampled for carbonyl compounds,
hexavalent chromium, and VOC, while ITCMI sampled only for SVOC. Table 14-2 presents the
pollutants that failed at least one screen at the Michigan monitoring sites.
The following observations are shown in Table 14-2:
• Sixteen pollutants with a total of 431 measured concentrations failed screens at
DEMI; 1 pollutant with one measured concentration failed screens at ITCMI.
• Carbon tetrachloride, benzene, formaldehyde, acetaldehyde, 1-3 butadiene,
tetrachloroethylene, acrolein, />-dichlorobenzene, and hexavalent chromium
contributed to the top 95 percent of the total failed screens at the DEMI monitoring
site.
• Only benzo(a)pyrene failed screens at ITCMI.
• Of the nine pollutants of interest for DEMI, acrolein, 1,3-butadiene, benzene, and
carbon tetrachloride had 100 percent of their measured detections fail the screening
values.
14-6
-------
Table 14-1. Average Meteorological Conditions near the Monitoring Sites in Michigan
Site
DEMI
ITCMI
WBAN
94847
14847
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperatur
e(°F)
59.95
± 1.84
61.05
±4.31
51.68
±2.03
52.23
±4.84
Average
Temperatur
e(°F)
52.16
±1.70
52.63
±3.96
43.92
±1.78
44.65
±4.19
Average
Dew Point
Temperatur
e(°F)
41.01
±1.67
41.57
±3.75
35.87
±1.66
36.32
±3.96
Average
Wet Bulb
Temperatur
e(°F)
46.73
±1.54
47.15
±3.50
40.23
±1.61
40.83
±3.81
Average
Relative
Humidity
(%)
68.35
± 1.23
69.12
±3.22
75.99
±1.21
75.19
±3.09
Average
Sea Level
Pressure
(mb)
1016.00
±0.74
1015.41
±1.69
1014.46
±0.80
1014.62
±1.47
Average
Scalar Wind
Speed
(kt)
7.65
±0.32
7.39
±0.72
6.46
±0.28
6.44
±0.69
-------
Table 14-2. Comparison of Measured Concentrations and EPA Screening Values
for the Michigan Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Dearborn in Detroit, Michigan - DEMI
Carbon Tetrachloride
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
Acrolein
£>-Dichlorobenzene
Hexavalent Chromium
Hexachloro- 1 ,3 -butadiene
Dichloromethane
1,2-Dichloroethane
Acrylonitrile
Vinyl chloride
Xylenes
Trichloroethylene
Total
58
58
58
58
53
51
47
18
13
5
4
o
5
2
1
1
1
431
58
58
60
60
53
55
47
49
55
5
57
3
2
5
58
23
648
100.00
100.00
96.67
96.67
100.00
92.73
100.00
36.73
23.64
100.00
7.02
100.00
100.00
20.00
1.72
4.35
66.51
13.46
13.46
13.46
13.46
12.30
11.83
10.90
4.18
3.02
1.16
0.93
0.70
0.46
0.23
0.23
0.23
13.46
26.91
40.37
53.83
66.13
77.96
88.86
93.04
96.06
97.22
98.14
98.84
99.30
99.54
99.77
100.00
Intertribal Council, Sault Sainte Marie, Michigan - ITCMI
Benzo (a) pyrene
Total
1
1
51
51
1.96
1.96
100.00
100.00
14.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there are at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
14-8
-------
presented in Table 14-3. Annual averages are presented and discussed in further detail in later
sections.
The following observations are shown in Table 14-3:
• Formaldehyde had the highest concentration by mass (2.91 ± 0.36 |ig/m3), followed
by acetaldehyde (1.65 ± 0.21 |ig/m3), and benzene (1.25 ± 0.21 |ig/m3).
• Most of the seasonal averages did not vary significantly, although formaldehyde's
summer average was significantly higher than any other summer average.
• Trichloroethylene's summer average had a very large confidence interval, indicating
that this average was likely influenced by outliers.
• At ITCMI, the daily average for benzo(a)pyrene was 1.555 ± 0.053 ng/m3.
14.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for Michigan monitoring sites was evaluated
using ATSDR short-term (acute) and intermediate MRL and California EPA acute REL factors.
Acute risk is defined as exposures from 1 to 14 days while intermediate risk is defined as
exposures from 15 to 364 days. It is useful to compare the preprocessed daily measurements to
the short term MRL and REL factors, as well as to compare seasonal averages to the
intermediate MRL. Of the pollutants with at least one failed screen, only acrolein, which was
sampled at DEMI, exceeded either the acute and intermediate risk values. DEMI's non-chronic
risk is summarized in Table 14-4.
The following observations about acrolein are shown in Table 14-4:
• All 47 acrolein measured detections at the DEMI site were greater than the ATSDR
acute value of 0.11 |ig/m3 and 43 were greater than the California REL value of 0.19
|ig/m3.
• All four seasonal averages of acrolein exceeded the intermediate MRL (0.09 |ig/m3).
14-9
-------
Table 14-3. Daily and Seasonal Averages for the Pollutants of Interest for the Michigan Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Hg/m3)
Conf.
Int.
Autumn
Avg
(Hg/m3)
Conf.
Int.
Dearborn in Detroit, Michigan - DEMI
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Hexavalent Chromium
Tetrachloroethylene
60
47
58
53
58
49
60
55
55
60
58
58
58
58
58
60
59
58
1.65
0.53
1.25
0.13
0.67
0.11
2.91
0.01
0.90
0.21
0.14
0.21
0.04
0.05
0.03
0.36
0.01
0.46
1.26
0.51
1.17
0.14
0.58
0.07
1.99
0.01
0.60
0.19
0.40
0.32
0.04
0.07
0.03
0.37
0.01
0.21
2.08
0.33
1.07
0.07
0.61
0.07
3.26
0.01
0.82
0.60
0.10
0.21
0.03
0.06
0.02
0.74
0.01
0.31
1.88
0.46
1.25
0.13
0.76
0.13
4.10
0.01
1.50
0.22
0.13
0.45
0.13
0.13
0.08
0.58
0.01
1.71
1.38
0.51
1.51
0.15
0.73
0.13
2.29
0.01
0.55
0.40
0.14
0.58
0.07
0.08
0.04
0.57
0.01
0.15
Sault Sainte Marie, Michigan - ITCMI
Benzo (a) pyrene
51
60
1.55E-04
5.30E-05
1.94E-04
1.39E-04
1.10E-04
4.63E-05
6.72E-05
4.56E-05
1.51E-04
9.06E-05
-------
Table 14-4. Non-Chronic Risk Summary for the Michigan Monitoring Sites
Site
DEMI
Method
TO- 15
Pollutant
Acrolein
Daily
Average
(ug/m3)
0.53
±0.14
ATSDR
Short-term
MRL
(ug/m3)
0.11
# of ATSDR
MRL
Exceedances
47
CAL EPA
REL Acute
(ug/m3)
0.19
# of CAL EPA
REL
Exceedances
43
ATSDR
Intermediate
-term MRL
(Ug/m3)
0.09
Winter
Average
(ug/m3)
0.51
±0.40
Spring
Average
(Ug/m3)
0.33
±0.10
Summer
Average
(Ug/m3)
0.46
±0.13
Autumn
Average
(Ug/m3)
0.51
±0.14
-------
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of
concentration and wind direction. Figure 14-5 presents the pollution rose for acrolein for DEMI.
Observations gleaned from the acrolein pollution rose include:
• All of the acrolein concentrations exceeded the ATSDR MRL acute risk factor, which
is indicated by a solid line.
• All but four acrolein concentrations exceeded the California EPA REL acute risk
factor, indicated by the dashed line.
• The concentrations exceeding acute risk factors occurred with winds originating from
a variety of directions, a pattern characteristic of mobile sources.
• The DEMI site is located in a suburban, yet industrial area, and is surrounded by
many railways and major interstates. 1-94 is located to the west and north and 1-75 is
located to the south and east of the site. Major auto and steel manufacturers are
located in close proximity to the site.
14.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
14.4.1 Pearson Correlation Analysis
Table 14-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the Michigan monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for DEMI from Table 14-5:
• Formaldehyde exhibited strong correlations with maximum, average, dew point, and
wet bulb temperatures. This indicates that as temperature and moisture content
increase, formaldehyde concentrations also increase.
14-12
-------
Figure 14-5. Acrolein Pollution Rose for DEMI
OJ
4.0
3.5
3.0
2.5
2.0
1.5
| 1'°
(0
•£ 0.5
1
•g
3 0.5
2
~O . r,
Q. 1.0
1.5
2.0
2.5
3.0
3.5
4.0
4
NW N
• «» »**
w * *t2i£
* *tJK
• *^
4
O\A/ O
0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0
^,————————————————————————————
3 NE
— CA EPA REL (0.19 |jg/m3)
— ATSDR MRL(0.11 pg/m3)
•
* «
^^ E
?vt *
•
Daily Ava Cone =0.53 ±0.14 ua/m3 SE
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4
Pollutant Concentration
-------
Table 14-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Michigan
Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar Wind
Speed
Dearborn in Detroit, Michigan - DEMI
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Hexavalent Chromium
Tetrachloroethylene
53
60
47
58
58
49
60
55
55
0.04
0.43
-0.15
0.04
0.29
0.06
0.69
0.18
0.23
0.00
0.37
-0.13
0.00
0.35
0.01
0.65
0.19
0.22
0.00
0.29
-0.14
0.04
0.38
0.04
0.52
0.22
0.17
-0.01
0.33
-0.14
0.01
0.37
0.02
0.59
0.20
0.19
0.02
-0.24
-0.01
0.12
0.04
0.06
-0.38
0.10
-0.16
0.11
0.11
0.11
0.16
-0.07
0.21
0.12
0.01
0.05
-0.23
-0.37
-0.06
-0.38
0.00
-0.31
-0.30
-0.22
-0.06
Sault St. Marie, Michigan - ITCMI
Benzo (a) pyrene
51
-0.25
-0.30
-0.31
-0.31
-0.06
0.20
-0.02
-------
• Though generally weak, all of the correlations with the scalar wind speed were
negative, indicating that as wind speeds decrease, concentrations of the pollutants of
interest at DEMI increase.
The following observations are gathered for ITCMI from Table 14-5:
• The correlations with benzo(a)pyrene were weak.
14.4.2 Composite Back Trajectory Analysis
Figures 14-6 and 14-7 are composite back trajectory maps for the Michigan monitoring
sites for the days on which sampling occurred. Each line represents the 24-hour trajectory alon|
which a parcel of air traveled toward the monitoring site on a sampling day. Each concentric
circle around the site represents 100 miles.
The following observations can be made from Figure 14-6 for DEMI:
• Back trajectories originated from a variety of directions at DEMI.
• The 24-hour airshed domain was large, with trajectories originating as far away as
North Dakota, or over 700 miles away.
• 61 percent of the trajectories originated within 300 miles of the site; and 71 percent
within 400 miles from the DEMI monitoring site.
The following observations can be made from Figure 14-7 for ITCMI:
• Back trajectories originated from a variety of directions at ITCMI, although less
frequently from the east and southeast.
• The 24-hour airshed domain was large, with trajectories originating as far away as
North Dakota, over 700 miles away.
• The majority of the trajectories originated over 300 miles away from the site.
14-15
-------
Figure 14-6. Composite Back Trajectory Map for DEMI
-------
Figure 14-7. Composite Back Trajectory Map for ITCMI
-------
14.4.3 Wind Rose Analysis
Hourly wind data from the weather stations nearest DEMI and ITCMI were uploaded into
a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces a graphical wind
rose from the wind data. A wind rose shows the frequency of wind directions about a 16-point
compass, and uses different shading to represent wind speeds. Figures 14-8 through 14-9 are the
wind roses for the Michigan monitoring sites on days that sampling occurred
Observations from Figure 14-8 for DEMI include:
• Hourly winds near DEMI originated from all directions.
• The most frequently measured wind directions were southerly, westerly, and west-
north westerly (9 percent, 8 percent, and 8 percent, respectively).
• Calm winds were recorded for 10 percent of the hourly observations.
• For wind speeds greater than 2 knots, observations most often ranged from 7 to 11
knots.
• Wind speeds greater than 22 knots were most frequently recorded with southerly to
westerly wind directions.
Observations from Figure 14-9 for ITCMI include:
• Hourly winds near ITCMI originated predominantly from the west-northwest (13
percent of the hourly observations), northwest (10 percent), west (8 percent), and east
(8 percent).
• Calm winds were recorded for 14 percent of the hourly measurements.
• For wind speeds greater than 2 knots, observations most often ranged from 7 to 11
knots.
• Stronger winds (11-17 knots) were most frequently observed from the west-northwest
and northwest.
14-18
-------
Figure 14-8. Wind Rose for DEMI Sampling Days
10%
8%,
; EAST
•SOUTH ,--•
WIND SPEED
(Knots)
-17 - 21
I I 11 - 17
^| 7- 11
I I 4- 7
• 2- 4
Calms: 9.96%
-------
Figure 14-9. Wind Rose for ITCMI Sampling Days
to
o
SOUTH .--•
WIND SPEED
(Knots)
17 - 21
I I 1-1 - 17
^| 7- 11
I I 4- 7
• 2- 4
Calms: 13.86%
-------
14.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as these sites did not sample for SNMOC.
14.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Chippewa County and Wayne
County, Michigan, were obtained from the Michigan Department of State and the U.S. Census
Bureau, and are summarized in Table 14-6. Table 14-6 also includes a vehicle registration to
county population ratio (vehicles per person). In addition, the population within 10 miles of
each site is presented. An estimation of 10-mile vehicle registration was computed using the 10-
mile population surrounding the monitor and the vehicle registration ratio. Finally, Table 14-6
contains the average daily traffic information, which represents the average number of vehicles
passing the monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 14-6 include:
• The DEMI site is located in Wayne County, and ITCMI is located in Chippewa
County.
• Wayne County has significantly more residents and registered vehicles than
Chippewa County.
• Wayne County has the fourth highest population and ninth highest vehicle
registration of all the UATMP sites.
• Although DEMI has a higher estimated vehicle ownership within a 10-mile radius
than ITCMI, the ITCMI site has a higher daily traffic volume.
• The ITCMI monitoring site has the third highest traffic volume of all the UATMP
sites.
14.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that the
concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
14-21
-------
to
to
Table 14-6. Motor Vehicle Information for the Michigan Monitoring Sites
Site
DEMI
ITCMI
2006 Estimated
County
Population
1,971,853
38,674
Number of
Vehicles
Registered
1,423,637
33,580
Vehicles per Person
(Registration: Population)
0.72
0.87
Population
Within 10 Miles
1,167,257
21,916
Estimated 10 Mile
Vehicle Ownership
842,735
19,029
Traffic Data
(Daily
Average)
12,791
100,000
-------
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compared them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road, or motor vehicle emissions.
The BTEX figure and table show the following:
• Similar to the roadside study, the toluene-ethylbenzene ratio was the highest ratio for
DEMI.
• But unlike the roadside study, the benzene-ethylbenzene ratio (4.92 ± 0.52) was
higher than the xylenes-ethylbenzene ratio (3.77 ± 0.20).
• ITCMI did not sample VOC.
14.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. DEMI is
the only site with sufficient data to conduct a trends analysis. The DEMI monitoring site has
consistently sampled VOC and carbonyls since 2001, as shown in Figure 14-10.
• After an initial decrease in formaldehyde concentrations in 2002, formaldehyde
concentrations increased in 2003. The high 2004 formaldehyde concentration was
probably influenced by outliers, as indicated by the confidence interval represented
by error bars. The average formaldehyde concentration decreased in 2006 from 2005.
• Concentrations of 1,3-butadiene and benzene have been fairly consistent throughout
the period.
14.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Michigan sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
14-23
-------
-^
to
Figure 14-10. Comparison of Yearly Averages for the DEMI Monitoring Site
2001
2002
2003
2004
2005
2006
Year
D1,3-Butadiene
I Benzene
D Form aldehyde
-------
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 14-7.
Additionally, the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA were
retrieved and are also presented in Table 14-7. The NATA data are presented for the census tract
where the monitoring site is located.
The census tract information for the Michigan sites is as follows:
• The census tract for DEMI is 26163573500, which had a population of 5,214 and
represents approximately 0.3 percent of the Wayne County population in 2000.
• The census tract for ITCMI is 26033970300, which had a population of 3,744, and
represents approximately 10 percent of the county population in 2000.
The following observations can be made for DEMI from Table 14-7:
• The pollutants with the top 3 annual averages by mass concentration at DEMI were
formaldehyde (2.91 ± 0.36 |ig/m3), xylenes (2.65 ± 0.53 |ig/m3), and acetaldehyde
(1.65 ±0.21 |ig/m3).
• The pollutants with the highest cancer risks were not these pollutants. The highest
theoretical cancer risks for DEMI were calculated for carbon tetrachloride (10.04 in-
a-million), benzene (9.77), and tetrachloroethylene (5.05).
• According to the 1999 NATA, benzene (29.55 in-a-million), 1,3-butadiene (10.06),
and acetaldehyde (5.72) had the highest cancer risk for pollutants that failed screens
at DEMI.
• Acrolein was the only pollutant that exhibited a noncancer HQ greater than 1,
according to both the 2006 annual average for DEMI (22.68) and the 1999 NATA
(9.52). All other noncancer HQs were less than 0.40
The following observations can be made for ITCMI from Table 14-7:
• Benzo(a)pyrene was the only pollutant to fail screens at ITCMI. This pollutant has
no noncancer risk factor; therefore, noncancer risk cannot be assessed.
• The NATA-modeled concentration and the annual average for benzo(a)pyrene were
both less than 0.01 |ig/m3.
• Cancer risk was low for both the NATA-modeled and the annual average-based risk.
14-25
-------
Table 14-7. Chronic Risk Summary for the Monitoring Sites in Michigan
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Ug/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(Ug/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk
(HQ)
Dearborn, Michigan (DEMI) - Census Tract ID 26163573500
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
1 ,2-Dichloroethane
Dichloromethane
Formaldehyde
Hexachloro- 1 , 3 -butadiene
Hexavalent Chromium
Tetrachloroethylene
Trichloroethylene
Vinyl chloride
Xylenes
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
0.000026
0.00000047
5.5E-09
0.000022
0.012
0.0000059
0.000002
0.0000088
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
2.4
1
0.0098
0.09
0.0001
0.27
0.6
0.1
0.1
2.60
0.19
0.01
3.79
0.34
0.21
0.08
0.04
0.69
2.58
0.01
O.01
0.37
0.11
0.07
6.69
5.72
NR
0.26
29.55
10.06
3.14
0.92
1.07
0.33
0.01
0.03
1.65
2.16
0.21
0.62
NR
0.29
9.52
0.01
0.13
0.17
0.01
0.01
O.01
O.01
0.26
0.01
O.01
O.01
0.01
0.01
0.07
1.65 ±0.21
0.45 ±0.12
0.07 ±0.01
1.25 ±0.21
0.12 ±0.04
0.67 ±0.05
0.10 ±0.03
0.09 ±0.11
0.55 ±0.19
2.91 ±0.36
0.09 ±0.02
O.01±O.01
0.86 ±0.43
0.13 ±0.14
0.04 ±0.05
2.65 ±0.53
3.63
NR
4.80
9.77
3.71
10.04
1.10
2.40
0.26
0.02
1.92
0.82
5.05
0.26
0.34
NR
0.18
22.68
0.04
0.04
0.06
0.02
0.01
O.01
O.01
0.30
0.01
O.01
O.01
0.01
0.01
0.03
Sault Ste. Marie, Michigan (ITCMI) - Census Tract ID 26033970300
Benzo (a) pyrene
0.001
NR
0.01
0.07
NR
0.01 ±0.01
0.13
NR
to
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
-------
14.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 14-8 and 14-9 present a
risk-based assessment of county-lev el emissions based on cancer and noncancer toxicity,
respectively. Table 14-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 14-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. DEMI sampled for VOC, hexavalent chromium, and carbonyl
compounds; ITCMI sampled for SVOC only. In addition, the highest cancer and noncancer risks
based on annual averages are limited to those pollutants failing at least one screen.
The following observations can be made for DEMI from Table 14-8:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor, had
second highest cancer toxicity-weighted emissions, and had the second highest cancer
risk based on the 2006 annual average for DEMI.
• Coke oven emissions had the highest cancer toxicity-weighted emissions in Wayne
County, but its total emissions were not in the top 10.
• Carbon tetrachloride had the highest cancer risk based on the 2006 annual average for
this site, yet this pollutant was neither one of the highest emitted nor one of the most
toxic based on the 2002 NEI emission inventory.
• Benzene, tetrachloroethylene, and 1,3-butadiene were shown on all three "top 10"
lists.
The following observations can be made for ITCMI from Table 14-8:
• Similar to Wayne County, benzene was the highest emitted pollutant with a cancer
risk factor in Chippewa County.
14-27
-------
Table 14-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Michigan
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer Risk
(in-a-
million)
Detroit, Michigan (DEMI) - Wayne County
Benzene
Formaldehyde
Tetrachloroethylene
Dichloromethane
Acetaldehyde
1,3 -Butadiene
1 , 3 -Dichloropropene
Naphthalene
£>-Dichlorobenzene
Trichloroethylene
1,901.76
740.64
388.05
290.39
272.58
192.12
147.66
113.19
76.63
47.80
Coke Oven Emissions
Benzene
1,3 -Butadiene
Quinoline
Polycyclic Organic Matter as 7-PAH
Naphthalene
Cadmium
Tetrachloroethylene
Lead
Polycyclic Organic Matter as 15 -PAH
2.50E-02
1.48E-02
5.76E-03
4.83E-03
4.25E-03
3.85E-03
3.16E-03
2.29E-03
2.15E-03
1.04E-03
Carbon Tetrachloride
Benzene
Tetrachloroethylene
Acrylonitrile
1,3 -Butadiene
Acetaldehyde
1 ,2-Dichloroethane
Hexachloro- 1 ,3 -butadiene
£>-Dichlorobenzene
Hexavalent Chromium
10.04
9.77
5.05
4.80
3.71
3.63
2.40
1.92
1.10
0.82
Sault Sainte Marie, Michigan (ITCMI) - Chippewa County
Benzene
Formaldehyde
Tetrachloroethylene
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Naphthalene
1 , 3 -Dichloropropene
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15 -PAH
81.74
23.56
18.23
9.84
7.28
6.13
2.90
2.81
1.50
1.46
Benzene
1,3 -Butadiene
Lead
Tetrachloroethylene
Naphthalene
Polycyclic Organic Matter as 15 -PAH
Polycyclic Organic Matter as 7-PAH
Arsenic
Polycyclic Organic Matter as non-15 PAH
Acrylonitrile
6.38E-04
2.18E-04
1.63E-04
1.08E-04
9.88E-05
8.03E-05
5.40E-05
5.30E-05
4.80E-05
4.51E-05
Benzo (a) pyrene
0.13
to
oo
-------
Table 14-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Michigan
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on Annual
Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk
(HQ)
Detroit, Michigan (DEMI) - Wayne County
Toluene
Xylenes
Benzene
Hydrochloric Acid
Methanol
Ethylbenzene
Formaldehyde
Hexane
Methyl Ethyl Ketone
Glycol Ethers
4,966.63
3,339.72
1,901.76
1,627.79
907.55
748.25
740.64
720.40
575.03
476.52
Acrolein
Manganese
1,3 -Butadiene
Cadmium
Hydrochloric Acid
Formaldehyde
Benzene
Bromomethane
Nickel
Naphthalene
2,046,078.60
96,059.90
87,737.35
81,389.73
75,575.59
63,391.91
41,215.89
40,571.14
37,730.55
Acrolein
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Benzene
Acrylonitrile
Xylenes
Carbon Tetrachloride
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
22.68
0.30
0.18
0.06
0.04
0.04
0.03
0.02
<0.01
<0.01
Sault Sainte Marie, Michigan (ITCMI) - Chippewa County
Toluene
Xylenes
Benzene
Ethylbenzene
Hexane
Formaldehyde
Tetrachloroethylene
Methanol
Methyl Ethyl Ketone
Acetaldehyde
324.83
208.66
81.74
46.52
35.65
23.56
18.23
15.69
11.55
9.84
Acrolein 330,598.26
1,3 -Butadiene
Benzene
Formaldehyde
Xylenes
Acetaldehyde
Naphthalene
Cyanide
Toluene
Bromomethane
70,535.51
3,640.69
2,724.67
2,404.12
2,086.61
1,093.23
968.19
953.02
812.07
783.24
Benzo (a) pyrene
NR
to
VO
-------
• Benzene also had the highest cancer toxicity-weighted emissions.
• The only SVOC to make either emissions-based top 10 list was naphthalene;
however, this pollutant did not fail any screens and was not included in this analysis.
• Benzo(a)pyrene, which did fail screens at ITCMI, was not one of the highest emitted
pollutants in Chippewa County and did not have one of the highest cancer toxicity-
weighted emissions according to the 2002 NEI.
The following observations can be made for DEMI from Table 14-9:
• Although toluene and xylenes were the highest emitted pollutants with noncancer risk
factors in Wayne County, they did not rank in the top 10 based on toxicity-weighted
emissions.
• Xylenes ranked seventh for DEMI for annual average-based noncancer risk; however,
the translated HQ was very low (0.03).
• Acrolein had the highest noncancer toxicity-weighted emissions in Wayne County
and the highest noncancer risk based on the 2006 annual average for DEMI, but did
not appear in the list of highest emitted pollutants.
• Formaldehyde, which had the highest daily and annual averages for DEMI, was one
of the 10 highest emitted pollutants in Wayne County. Its noncancer toxicity-
weighted emissions ranked sixth, and the noncancer risk based on the 2006 annual
average ranked second.
The following observations can be made for ITCMI from Table 14-9:
• Similar to Wayne County, toluene and xylenes were the highest emitted (by mass)
pollutants with noncancer risk factors in Chippewa County; however unlike Wayne
County, these two pollutants also ranked in the top 10 for the highest noncancer
toxicity-weighted emissions.
• Acrolein also had the highest noncancer toxicity-weighted emissions in Chippewa
County.
• As mentioned in previously, benzo(a)pyrene does not have a noncancer risk factor.
14-30
-------
Michigan Pollutant Summary
The pollutants of interest for DEMI included carbon tetrachloride, benzene,
formaldehyde, acetaldehyde, 1,3-butadiene, tetrachloroethylene, acrolein, p-
dichlorobenzene, and hexavalent chromium. Benzo(a)pyrene was the only pollutant of
interest for ITCMI.
Formaldehyde had the highest daily average for DEMI.
Acrolein exceeded the short-term risk factors at DEMI.
Formaldehyde decreased at DEMI from 2005 to 2006.
14-31
-------
15.0 Site in Minnesota
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Minneapolis, Minnesota (MIMN). Figure 15-1 is a topographical map showing the
monitoring site in its urban location. Figure 15-2 identifies point source emission locations
within 10 miles of this site as reported in the 2002 NEI for point sources. The Minneapolis site
is surrounded by numerous point sources, of which a majority are involved in fuel combustion
processes.
The Mississippi River runs through the center of Minneapolis and connects with the
Minnesota River in southwest St. Paul. The city has many small lakes, which freeze in the
winter. The city experiences a continental climate, generally cold in the winter and warm in the
summer. Winds fluctuate seasonally, and tend to be out of the southeast in the summer and fall,
and out of the northwest in the winter and spring. Although precipitation in the area isn't great,
the spring thaw in conjunction with the river system can lead to flooding in the spring. (Ruffner
andBair, 1987).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the MIMN monitoring site is at Minneapolis-St. Paul International Airport (WBAN 14922).
Table 15-1 presents average meteorological conditions of temperature (average
maximum and average), moisture (average dew point temperature, average wet-bulb
temperature, and average relative humidity), pressure (average sea level pressure), and wind
information (average scalar wind speed) for the entire year and on days samples were collected.
Also included in Table 15-1 is the 95 percent confidence interval for each parameter. As shown
in Table 15-1, average meteorological conditions on sampling days were somewhat cooler and
slightly windier than average weather conditions throughout the year. The site sampled only
until the end of April, missing nearly all the warmer months; this shorter sampling period
probably attributed to this difference.
15-1
-------
Figure 15-1. Minneapolis, Minnesota (MIMN) Monitoring Site
Source: USGS 7.5 Minutes Series. Map Scale: 1:24,000
15-2
-------
Figure 15-2. Facilities Located Within 10 Miles of MIMN
An oka
County
F ff
i1""1- _ Ramsey
g '*••• County
- - DFi-- -'-.-
* IF
B I F V
. I «i F
Hennepin
County
PFF
F
•RF P
F LF
, Fp R F
.f1 F . .
Dakota
County
ri
-V-'
Legend
"A" MIMN UATMP site
Note: Due to facility density and collocation, the total facilities
displayed may not represent afl facilities within the area of interest
10 mile radius
Source Category Group (No. of Facilities)
- Agricultural Production - Crops (1)
± Automobile Dealers (1)
* Automotive Repair, Services. & Parking (3)
z Electrical & Electronic Equipment Facility (2)
-i- Executive, Legislative, & General Government Facility (1)
o Fabricated Metal Products Facility (7)
G Food & Kindred Products Facility (1)
F Fuel Combustion Industrial Facility (159)
I Incineration Industrial Facility (1}
j Industrial Machinery & Equipment Facility (18)
t- Integrated Iron & Steel Manufacturing Facility (4)
L Liquids Distribution Industrial Facility (3)
& Lumber & Wood Products Facility (4)
B Mineral Products Processing Industrial Facility (7)
County boundary
x Miscellaneous Manufacturing Industries (1)
p Miscellaneous Processes Industrial Facility (24)
\ Non-ferrous Metals Processing Industrial Facility (4)
2 Nonmetallic Minerals, Except Fuels (1)
@ Paper & Allied Products (1)
R Printing & Publishing Facility (13)
4 Production of Organic Chemicals Industrial Facility (4)
Y Rubber & Miscellaneous Plastic Products Facility (2)
D Special Trade Contractors Facility (1)
s Surface Coating Processes Industrial Facility (15)
T Transportation Equipment (1)
-f Transportation by Air (2)
8 Utility Boilers (5)
'•: Waste Treatment & Disposal Industrial Facility (2)
r Wholesale Trade (1)
15-3
-------
Table 15-1. Average Meteorological Conditions near the Monitoring Site in Minnesota
Site
MIMN
WBAN
14922
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(»F)
57.42
±2.22
41.32
±7.40
Average
Temperature
(°F)
49.63
±2.10
34.29
±6.81
Average
Dew Point
Temperature
(OF)
36.56
±1.87
21.90
±5.45
Average
Wet Bulb
Temperature
(°F)
43.35
±1.79
29.61
±5.48
Average
Relative
Humidity
(%)
64.06
±1.39
64.58
±7.55
Average
Sea Level
Pressure
(mb)
1015.45
±0.79
1015.15
±3.78
Average
Scalar Wind
Speed
(kt)
7.92
±0.29
8.38
± 1.14
-------
15.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Michigan
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. The MIMN site sampled for carbonyls,
VOC, and metals. Table 15-2 presents the fourteen pollutants that failed at least one screen at
MIMN.
Table 15-2. Comparison of Measured Concentrations and EPA Screening Values for the
Minnesota Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Minneapolis, Minnesota - MIMN
Acetaldehyde
Benzene
Carbon Tetrachloride
1,3 -Butadiene
Manganese (TSP)
Arsenic (TSP)
Tetrachloroethylene
Formaldehyde
Acrolein
£>-Dichlorobenzene
Nickel (TSP)
Cadmium (TSP)
Hexachloro- 1 , 3 -butadiene
Trichloroethylene
Total
17
16
16
14
11
11
7
6
5
4
3
1
1
1
113
17
16
16
14
12
12
9
17
5
9
12
12
1
6
158
100.00
100.00
100.00
100.00
91.67
91.67
77.78
35.29
100.00
44.44
25.00
8.33
100.00
16.67
71.52
15.04
14.16
14.16
12.39
9.73
9.73
6.19
5.31
4.42
3.54
2.65
0.88
0.88
0.88
15.04
29.20
43.36
55.75
65.49
75.22
81.42
86.73
91.15
94.69
97.35
98.23
99.12
100.00
The following observations are shown in Table 15-2:
• A total of 125 measured concentrations failed screens.
• The risk screening process for MIMN resulted in eleven pollutants of interest:
acetaldehyde (17 failed screens), benzene (16), carbon tetrachloride (16), arsenic (11),
15-5
-------
manganese (11), 1,3-butadiene (14), formaldehyde (6), tetrachloroethylene (7),
acrolein (5), /?-dichlorobenzene (4), and nickel (3).
• Of the eleven pollutants of interest, acetaldehyde, benzene, carbon tetrachloride,
acrolein, and 1,3-butadiene had 100 percent of their measured detections fail the
screening values.
15.2 Concentration Averages
Three types of concentration averages were calculated for the twelve pollutants of
interest: daily, seasonal, and annual. The daily average of a particular pollutant is simply the
average concentration of all measured detections. If there are at least seven measured detections
within each season, then a seasonal average was calculated. The seasonal average includes 1/2
MDLs substituted for all non-detects. A seasonal average was not calculated for pollutants with
less than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 15-3. Annual averages are presented and discussed in further detail in later
sections.
The following observations are shown in Table 15-3:
• Acetaldehyde, arsenic, benzene, carbon tetrachloride, formaldehyde, and manganese
were detected in every sample collected at MIMN, while acrolein, />-dichlorobenzene,
tetrachloroethylene, nickel, and 1,3-butadiene were detected in one-half or less of the
samples collected.
• Among the daily averages for MIMN, formaldehyde, acetaldehyde, and benzene had
the highest concentrations by mass (0.93 ± 0.17 |ig/m3, 0.92 ± 0.13 |ig/m3, and 0.92 ±
0.08 |ig/m3, respectively).
• Both formaldehyde and acetaldehyde were higher in spring than winter.
• MIMN sampled metals until mid-March, and therefore has only winter seasonal
averages for these pollutants. Carbonyls and VOC were sampled from January
through April, so no summer or autumn seasonal averages could be calculated.
15-6
-------
Table 15-3. Daily and Seasonal Averages for the Pollutants of Interest for the Minnesota Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Ug/m3)
Conf.
Int.
Autumn
Avg
(Ug/m3)
Conf.
Int.
Minneapolis, Minnesota - MIMN
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Manganese (TSP)
Nickel (TSP)
Tetrachloroethylene
17
5
12
16
14
16
9
17
12
12
9
17
16
12
16
16
16
16
17
12
12
16
0.92
0.39
0.0005
0.92
0.11
0.64
0.10
0.93
0.0120
0.0031
0.20
0.13
0.13
0.0001
0.08
0.02
0.09
0.04
0.17
0.0030
0.0022
0.03
0.75
NR
0.0005
0.89
0.10
0.60
NR
0.71
0.0127
0.0036
NR
0.15
NR
0.0001
0.09
0.01
0.10
NR
0.11
0.0039
0.0029
NR
1.06
NR
NA
0.96
NR
0.69
0.11
1.12
NR
NR
NR
0.14
NR
NA
0.14
NR
0.13
0.04
0.25
NR
NR
NR
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
-------
15.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for MIMN was evaluated using ATSDR
short-term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is
defined as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15
to 364 days. It is useful to compare the preprocessed daily measurements to the short-term MRL
and REL factors, as well as compare seasonal averages to the intermediate MRL. Of the
fourteen pollutants with at least one failed screen, only acrolein exceeded both short-term risk
values, and its non-chronic risk is summarized in Table 15-4.
The following observations about acrolein are shown in Table 15-4:
• Five acrolein measured detections were greater than the ATSDR acute value of 0.11
|ig/m3 and the California REL value of 0.19 |ig/m3.
• The average detected concentration was 0.39 ±0.13 |ig/m3, which was nearly twice
the California REL value.
• Due to the low number of measured detections, seasonal averages could not be
calculated for comparison to the ATSDR intermediate risk level.
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of daily
concentration and daily average wind direction. Figure 15-3 is a pollution rose for acrolein for
MIMN.
Observations gleaned from the acrolein pollution rose include:
• All acrolein concentrations exceeded the ATDSR MRL acute risk factor, indicated by
a solid line, and the CalEPA REL acute risk factor, indicated by a dashed line.
• The concentrations on the pollution rose are scattered around the center, a pattern
characteristic of mobile sources.
• MIMN is located in downtown Minneapolis and is situated near several major
roadways (Figure 15-1). The immediate vicinity is mostly shops and offices,
although industrial sources are located within a mile of the monitoring site.
15-8
-------
Table 15-4. Non-Chronic Risk Summary for the Minnesota Monitoring Site
Site
MIMN
Method
TO- 15
Pollutant
Acrolein
Daily
Average
(ug/m3)
0.39
±0.13
ATSDR
Short-term
MRL
(ug/m3)
0.11
# of ATSDR
MRL
Exceedances
5
CAL EPA
REL Acute
(ug/m3)
0.19
# of CAL
EPA REL
Exceedances
5
ATSDR
Intermediate-
term MRL
(Ug/m3)
0.09
Winter
Average
(Ug/m3)
NR
Spring
Average
(ug/m3)
NR
Summer
Average
(Ug/m3)
NA
Autumn
Average
(ug/m3)
NA
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
-------
Figure 15-3. Acrolein Pollution Rose for MIMN
3.0
2.5
2.0
1.5
1.0
O
IB
2 0.5
.p
c
01
o
O 0.0
O I
NW
W
— CA EPA REL (0.19 (jg/rrT)
— ATSDR MRL (0.11 M9/m3)
N
NE
0.5
O
Q.
1.0
1.5
2.0
2.5
SW
3.0
Daily Avg Cone =0.39 ± 0.13 ud/m
3.0 2.5
2.0 1.5 1.0 0.5 0.0 0.5
Pollutant Concentration
1.0
1.5
2.0
2.5
SE
3.0
-------
15.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
15.4.1 Pearson Correlation Analysis
Table 15-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the MIMN monitoring site.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered from Table 15-5:
• Formaldehyde, acetaldehyde, and/>-dichlorobenzene exhibited strong positive
correlations with maximum and average temperatures, indicating that as temperatures
increase, concentrations of these pollutants also increase.
• Several pollutants exhibited strong correlations with the individual moisture
parameters, although not consistently across all the moisture parameters.
• Acrolein exhibited strong correlation with several parameters, although the low
number of measured detections may skew the correlations.
15.4.2 Composite Back Trajectory Analysis
Figure 15-4 is a composite back trajectory map for the MIMN monitoring site for the
days on which sampling occurred. Each line represents the 24-hour trajectory along which a
parcel of air traveled toward the monitoring site on a sampling day. Each concentric circle
around the site in Figure 15-4 represents 100 miles.
The following observations can be made from Figure 15-4:
• Back trajectories originated from a variety of directions at MIMN, although less
frequently from the southeast.
• The 24-hour airshed domain was somewhat large, with trajectories originating as far
away as Saskatchewan Canada (> 600 miles).
• Over half of the trajectories originated more than 400 miles away from of the site.
15-11
-------
Table 15-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Minnesota Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Minneapolis, Minnesota - MIMN
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Formaldehyde
Manganese (TSP)
Nickel (TSP)
£>-Dichlorobenzene
Tetrachloroethylene
17
5
12
16
14
16
17
12
12
9
9
0.75
-0.20
0.06
-0.21
0.12
0.15
0.64
0.04
0.37
0.64
-0.42
0.69
-0.27
0.09
-0.24
-0.01
0.28
0.62
-0.25
0.07
0.61
-0.35
0.39
-0.56
-0.21
-0.25
-0.14
0.52
0.48
-0.49
0.14
0.24
0.45
0.61
-0.38
-0.02
-0.24
-0.07
0.38
0.60
-0.36
0.08
0.49
-0.15
-0.63
-0.72
-0.47
-0.07
-0.28
0.41
-0.38
-0.61
0.14
-0.44
0.77
-0.19
0.82
-0.05
0.46
0.47
0.05
-0.32
0.25
-0.31
-0.16
-0.13
-0.27
-0.51
0.10
-0.42
-0.60
-0.21
0.04
0.19
-0.22
0.23
-0.08
-------
Figure 15-4. Composite Back Trajectory Map for MIMN
-------
15.4.3 Wind Rose Analysis
Hourly wind data from the Minneapolis-St. Paul International Airport near the MIMN
monitoring site was uploaded into a wind rose software program, WRPLOT (Lakes, 2006).
WRPLOT produces a graphical wind rose from the wind data. A wind rose shows the frequency
of wind directions about a 16-point compass, and uses different shading to represent wind
speeds. Figure 15-5 is the wind rose for the MIMN monitoring site on days that sampling
occurred.
Observations from Figure 15-5 include:
• Hourly winds were predominantly out of the northwest (13 percent observations),
north-northwest (13 percent), and east-southeast (11 percent) on sampling days.
• Wind speeds ranged from 7 to 11 knots on sampling days.
• Calm winds (<2 knots) were observed for five percent of the observations.
15.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as this site did not sample for SNMOC.
15.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Hennepin County, Minnesota were
obtained from the Minnesota Department of Public Safety - Driver and Vehicle Services and the
U.S. Census Bureau, and are summarized in Table 15-6. Table 15-6 also includes a vehicle
registration to county population ratio (vehicles per person). In addition, the population within
10 miles of each site is presented. An estimation of 10-mile vehicle registration was computed
using the 10-mile population surrounding the monitor and the vehicle registration ratio. Finally,
Table 15-6 contains the average daily traffic information, which represents the average number
of vehicles passing the monitoring sites on the nearest roadway to each site on a daily basis.
15-14
-------
Figure 15-5. Wind Rose for MIMN Sampling Days
SOUTH .--•
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
^| 11 - 17
I I 1- 7
• 2- 4
Calms: 5.37%
-------
Table 15-6. Motor Vehicle Information for the Minnesota Monitoring Site
Site
MIMN
2006 Estimated
County
Population
1,122,093
Number of
Vehicles
Registered
1,097,109
Vehicles per Person
(Registration:
Population)
0.98
Population
Within 10 Miles
1,131,912
Estimated
10 Mile Vehicle
Ownership
1,106,709
Traffic Data
(Daily Average)
10,000
-------
Observations gleaned from Table 15-6 include:
• Hennepin County is one of the twelve counties in the UATMP with a population over
1 million.
• Vehicle registration count is also high compared to other UATMP sites.
• MIMN's estimated 10 mile vehicle ownership is fifth behind sites from the northern
New Jersey, Phoenix, Arizona and Ft. Lauderdale, Florida.
• The average daily traffic count falls in the middle of the range compared to other
UATMP sites.
• The MIMN monitoring site is located in a commercial area and is in an urban-city
center setting.
15.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area. For more information on this study, refer to Section 3.2.1.4. Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compares them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• For MIMN, the benzene-ethylbenzene ratio (4.71 ± 0.33) was higher than the
xylenes-ethylbenzene ratio (3.75 ± 0.12), which is the opposite of the roadside study
(3.75 and 4.55, respectively).
• The toluene-ethylbenzene ratio (5.90 ± 0.42) was the highest ratio for MIMN, which
is similar to the roadside study (5.85).
15.6 Trends Analysis
A trends analysis could not be performed for MIMN as this site has not participated in the
UATMP for three consecutive years.
15-17
-------
15.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
MIMN and where the annual average concentrations could be calculated (refer to Section 3.3.5
regarding the definition of an annual average). Because MIMN completed sampling in April
2006, annual averages could not be calculated. As a result, no chronic risk analyses could be
performed. However, data from EPA's 1999 NAT A for the pollutants that failed at least one
screen at MIMN were retrieved and are presented in Table 15-7. The NATA data are presented
for the census tract where the monitoring site is located. The pollutants of interest are bolded in
Table 15-7.
The census tract information for MIMN is as follows:
• The MIMN monitoring site is located in census tract 27053104600.
• The population for the census tract where the SDGA monitoring site is located was
3,082, which represents approximately 0.3 percent of Hennepin County's population
in 2000.
The following observations can be made from Table 15-7:
• According to NATA, benzene, acetaldehyde, and formaldehyde had the highest
modeled-concentrations, while benzene, 1,3-butadiene, and acetaldehyde had the
highest cancer risks.
• The MIMN census tract's benzene cancer risk (39 in-a-million) was one of the
highest risks for any UATMP sites, behind only ININ's arsenic (208 in-a-million) and
BAPR's dichloromethane (71 in-a-million) cancer risks.
• Acrolein had the only NATA-modeled noncancer HQ greater than 1 (10.81). The
remaining noncancer HQs were less than 0.40.
15.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 15-7 and 15-8 present a
risk-based assessment of the county-level emissions based on cancer and noncancer toxicity,
respectively. Table 15-8 presents the 10 pollutants with the highest emissions from the 2002
NEI and the 10 pollutants with the highest cancer toxicity-weighted emissions. Table 15-9
presents similar information, but is based noncancer risk factors. The pollutants in these tables
15-18
-------
Table 15-7. Chronic Risk Summary for the Monitoring Site in Minnesota
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Ug/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk
(HQ)
Minneapolis, Minnesota (MIMN) - Census Tract ID 27053104600
Acetaldehyde
Acrolein
Arsenic*
Benzene
1,3-Butadiene
Cadmium*
Carbon Tetrachloride
p-D ichlo rob enzene
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese*
Nickel*
Tetrachloroethylene
Trichloroethylene
0.0000022
NR
0.0043
0.0000078
0.00003
0.0018
0.000015
0.000011
5.5E-09
0.000022
NR
0.00016
0.0000059
0.000002
0.009
0.00002
0.00003
0.03
0.002
0.00002
0.04
0.8
0.0098
0.09
0.00005
0.000065
0.27
0.6
3.22
0.22
0.15
5.06
0.47
0.14
0.21
0.06
3.12
<0.01
0.36
1.1
0.35
0.57
7.08
NR
0.64
39.5
14.18
0.25
3.18
0.69
0.02
0.03
NR
0.18
2.04
1.13
0.36
10.81
<0.01
0.17
0.24
0.01
0.01
<0.01
0.32
<0.01
0.01
0.02
<0.01
0.01
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
VO
* Metals sampled for TSP
BOLD = pollutants of interest
NA = no annual averages available
NR = no risk factor available.
-------
Table 15-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for MIMN
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(for Hennepin County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Hennepin County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on
Annual Average Concentration
(for MIMN)
Cancer Risk
Pollutant (in-a-million)
Minneapolis, Minnesota - MIMN
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Trichloroethylene
1 ,3 -Dichloropropene
Naphthalene
Tetrachloroethylene
£>-Dichlorobenzene
Dichloromethane
952.91
471.14
239.57
104.84
88.85
81.63
61.60
49.95
42.13
34.81
Benzene
Arsenic
1,3 -Butadiene
Lead
Cadmium
Naphthalene
Hexavalent Chromium
Poly cyclic Organic Matter as no n- 15 -PAH
Poly cyclic Organic Matter as 15 -PAH
Polycyclic Organic Matter as 7-PAH
7.43E-03
4.69E-03
3.15E-03
2.53E-03
2.48E-03
2.09E-03
1.57E-03
1.34E-03
7.20E-04
5.76E-04
to
o
-------
Table 15-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for MIMN
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Hennepin County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Hennepin County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for MIMN)
Noncancer
Risk
Pollutant (HQ)
Minneapolis, Minnesota - MIMN
Toluene
Xylenes
Benzene
Hexane
Formaldehyde
Ethylbenzene
Hydrochloric Acid
Acetaldehyde
1,1,1 -Trichloroethane
Methanol
2,180.15
1,413.29
952.91
594.14
471.14
315.77
302.71
239.57
222.58
211.66
Acrolein
Cadmium
1,3 -Butadiene
Formaldehyde
Arsenic
Nickel
Benzene
Acetaldehyde
Bromomethane
4,4'-MethylenediphenylDiisocyanate
1,517,588.62
68,812.07
52,421.07
48,075.66
36,354.75
34,602.06
31,763.64
26,618.50
22,778.27
21,406.70
to
-------
are limited to those that have cancer and noncancer risk factors, respectively. As a result, the
highest emitted pollutants in the cancer table may not be the same as the noncancer table,
although the actual value of the emissions will be. The pollutants with the highest cancer and
noncancer risks could not be calculated because annual averages could not be determined for
MIMN.
The following observations can be made from Table 15-8:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor in
Hennepin County.
• Benzene also had the highest cancer toxicity-weighted emissions.
• Benzene, 1,3-butadiene, and naphthalene were the only three pollutants that were on
both the highest emitted and the highest toxicity-weighted emissions "top 10" lists.
• While VOCs and carbonyls tended to be emitted most, metals and PAHs tended to be
the most toxic.
The following observations can be made from Table 15-9:
• Although toluene and xylenes were the highest emitted pollutants (by mass) with
noncancer risk factors in Hennepin County, only benzene ranked in the top 10 based
on toxicity-weighted emissions.
• Acrolein had the highest noncancer toxicity-weighted emissions even though this
pollutant did not appear in the list of highest emitted pollutants.
• Benzene, formaldehyde, and acetaldehyde were the only three pollutants that were on
both the highest emitted and the highest noncancer toxicity-weighted emissions "top
10" lists.
Minnesota Pollutant Summary
• The pollutants of interest for the Minnesota site were acetaldehyde, acrolein, arsenic,
benzene, 1,3-butadiene, carbon tetrachloride, formaldehyde, manganese, nickel
p-dichlorobenzene, and tetrachloroethylene.
• Formaldehyde had the highest daily average for MIMN. Concentrations of formaldehyde
were highest in spring.
• Acrolein was the only pollutant to exceed either of the short-term risk factors.
15-22
-------
16.0 Sites in Mississippi
This section presents meteorological, concentration, and spatial trends for the two
UATMP sites in Mississippi (GPMS, TUMS). These sites are located in two cities in
Mississippi: Gulfport and Tupelo, respectively. Figures 16-1 and 16-2 are topographical maps
showing the monitoring sites in their urban and rural locations. Figures 16-3 through 16-4
identify point source emission locations within 10 miles of the sites that reported to the 2002 NEI
for point sources. Few point sources are located near the GPMS site, which is located on the
Gulf Coast. Most of the sources are located to the north of the site and the majority are involved
in surface coating processes. The point sources within a 10 mile radius of TUMS, which is
located in northeast Mississippi, are mainly to the east and southeast of the site. A number of the
sources near the TUMS site are involved in surface coating processes, polymer and resin
production, and chemical and allied products production.
Climatologically, both of the Mississippi cities are warm and humid, especially Gulfport,
the site nearest the coast. High temperatures and humidity, due to proximity to the Gulf of
Mexico, can make this region feel uncomfortable. Precipitation is distributed fairly evenly
throughout the year, and thunderstorms are fairly common, especially in the summer and nearer
to the coast (Ruffner and Bair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the GPMS monitoring site is Gulfport-Biloxi Regional Airport (WBAN 93878); and the
closest weather station to TUMS site is Tupelo Municipal Airport (WBAN 93862). Table 16-1
presents average meteorological conditions of temperature (average maximum and average),
moisture (average dew point temperature, average wet-bulb temperature, and average relative
humidity), pressure (average sea level pressure), and wind information (average scalar wind
speed wind) for the entire year and on days samples were collected. Also included in Table 16-1
is the 95 percent confidence interval for each parameter. As shown in Table 16-1,
16-1
-------
Figure 16-1. Gulfport, Mississippi (GPMS) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
16-2
-------
Figure 16-2. Tupelo, Mississippi (TUMS) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
16-3
-------
Figure 16-3. Facilities Located Within 10 Miles of GPMS
Note: Due to facility density and collocation, the total facilities
displayed may not represent all facilities within the area of Mer
Legend
••&• GPMS UATMP Site
10 mile radius
County boundary
Source Category Group (No. of Facilities)
D Fabricated Metal Products Facility (1)
L Liquids Distribution Industrial Facility (1)
* Lumber & Wood Products Facility (1)
National Security 8 International Affairs (1)
\ Non-ferrous Metals Processing Industrial Facility (1)
u Stone. Clay, Glass. & Concrete Products (1)
s Surface Coating Processes Industrial Facility (5)
8 Utility Boilers (1)
i Waste Treatment & Disposal Industrial Facility (1)
16-4
-------
Figure 16-4. Facilities Located Within 10 Miles of TUMS
Comfy
Ft U
S
Pontoloc
County
Legend
•&• TUMS UATMP site
10 mile radius
I County boundary
Source Category Group (No. of Facilities)
Chemicals & Allied Products Facility (3)
Fabricated Metal Products Facility (1)
Fuel Combustion industrial Facility (1)
Health Services Facility (1)
Miscellaneous Processes Industrial Facility (1)
Polymers & Resins Production Industrial Facility (4)
Stone. Clay. Glass. & Concrete Products (1)
Surface Coating Processes Industrial Facility (5)
Waste Treatment & Disposal Industrial Facility (1)
Note: Due to fadlfty density and co3E&ca!it*i. the total fadlities
displayed may no! represent all facilities y«!!hm the area of interest
16-5
-------
Table 16-1. Average Meteorological Conditions near the Monitoring Sites in Mississippi
Site
GPMS
TUMS
WBAN
93874
93862
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
77.72
± 1.18
76.21
±2.65
79.15
±1.17
74.93
±4.08
Average
Temperature
(»F)
68.82
±1.26
66.67
±2.67
67.59
±1.22
64.37
±3.78
Average
Dew Point
Temperature
(°F)
57.98
± 1.47
55.10
±3.14
57.37
±1.45
51.21
±3.37
Average
Wet Bulb
Temperature
(°F)
62.60
±1.23
60.22
±2.60
61.74
±1.22
56.92
±3.16
Average
Relative
Humidity
(%)
71.21
±1.19
69.77
±2.84
72.92
±1.00
65.96
±2.79
Average
Sea Level
Pressure
fmh)
1017.35
±0.50
1017.69
±1.03
1017.72
±0.49
1017.06
±1.19
Average
Scalar Wind
Speed
(kt)
5.78
±0.29
6.13
±0.69
4.15
±0.26
5.73
±0.67
Oi
-------
average meteorological conditions on sampling days at GPMS and TUMS were fairly
representative of average weather conditions throughout the year.
16.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Michigan
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total screens. TUMS sampled for carbonyls and VOC, while
GPMS sampled for SVOC and SNMOC in addition to carbonyls and VOC. GPMS initially
sampled at a l-in-3 day schedule as part of the post-Katrina monitoring effort. As a result, this
site has more samples than most UATMP sites. Table 16-2 presents the pollutants that failed at
least one screen at the Mississippi monitoring sites.
The following observations are shown in Table 16-2:
• 14 pollutants with a total of 505 measured concentrations failed screens at GPMS;
11 pollutants with a total of 338 measured concentrations failed the screen at TUMS.
• The pollutants of interest also varied by site, yet the following seven pollutants
contributed to the top 95 percent of the total failed screens at both Mississippi
monitoring sites: acetaldehyde, acrolein, benzene, l,3-butadiene,/?-dichlorobenzene,
formaldehyde, carbon tetrachloride.
• Of the seven pollutants of interest that were the same at both sites, three pollutants of
interest, acrolein, benzene and carbon tetrachloride, had all 100 percent of their
measured detections fail screens.
• GPMS sampled for SVOC through October. While />-dichlorobenzene and 1,4-
dichlorobenzene are the same pollutant with different names, they are sampled with
different methods (as a VOC and an SVOC, respectively). Because resulting data
were obtained using two separate methods, they will be kept separate in this and
subsequent analyses. "/>-Dichlorobenzene" refers to the pollutant measured with the
16-7
-------
Table 16-2. Comparison of Measured Concentrations and EPA Screening Values for
the Mississippi Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Gulfport, Mississippi - GPMS
Formaldehyde
Acetaldehyde
Benzene
Carbon Tetrachloride
Acrolein
1,3 -Butadiene
£>-Dichlorobenzene
Naphthalene
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
1 ,4-Dichlorobenzene
Acrylonitrile
Xylenes
Dichloromethane
Total
71
71
68
68
65
56
46
42
8
5
2
1
1
1
505
71
71
68
68
65
61
60
60
37
5
56
1
68
66
757
100.00
100.00
100.00
100.00
100.00
91.80
76.67
70.00
21.62
100.00
3.57
100.00
1.47
1.52
66.71
14.06
14.06
13.47
13.47
12.87
11.09
9.11
8.32
1.58
0.99
0.40
0.20
0.20
0.20
14.06
28.12
41.58
55.05
67.92
79.01
88.12
96.44
98.02
99.01
99.41
99.60
99.80
100.00
Tupelo, Mississippi - TUMS
Carbon Tetrachloride
Acetaldehyde
Benzene
Acrolein
Formaldehyde
1,3 -Butadiene
£>-Dichlorobenzene
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
Acrylonitrile
1 ,2-Dichloroethane
Total
60
60
60
47
40
37
15
13
3
2
1
338
60
61
60
47
61
47
36
33
3
2
1
411
100.00
98.36
100.00
100.00
65.57
78.72
41.67
39.39
100.00
100.00
100.00
82.24
17.75
17.75
17.75
13.91
11.83
10.95
4.44
3.85
0.89
0.59
0.30
17.75
35.50
53.25
67.16
78.99
89.94
94.38
98.22
99.11
99.70
100.00
TO-15 (VOC) method and "1,4-dichlorobenzene" refers to the pollutant measured
with the 8270C (SVOC) method.
16.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
16-8
-------
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. The daily and seasonal averages are presented in
Table 16-3. Annual average concentrations are presented and discussed in further detail in later
sections.
The following observations are shown in Table 16-3:
• Formaldehyde had the highest concentration by mass (2.91 ± 0.40 |ig/m3) for GPMS,
followed by acetaldehyde (1.74 ± 0.17 jig/m3).
• Seasonal averages of the pollutants of interest for GPMS peaked in the summer or
autumn.
• For TUMS, the pollutants with the highest daily averages were acetaldehyde (1.95 ±
0.24 |ig/m3) and formaldehyde (1.58 ± 0.26 |ig/m3).
• Most of the seasonal averages for TUMS did not vary much from season-to-season,
when the confidence interval was considered.
• Acetaldehyde concentrations tended to be lower in winter; carbon tetrachloride was
highest in summer and autumn; and formaldehyde was highest in the summer.
16.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for the Mississippi monitoring sites was
evaluated using ATSDR short-term (acute) and intermediate MRL and California EPA acute
CALEPA REL factors. Acute risk is defined as exposures from 1 to 14 days while intermediate
risk is defined as exposures from 15 to 364 days. It is useful to compare the preprocessed daily
measurements to the short-term MRL and REL factors, as well as compare seasonal averages to
the intermediate MRL. Of the pollutants with at least one failed screen, only acrolein exceeded
16-9
-------
Table 16-3. Daily and Seasonal Averages for the Pollutants of Interest for the Mississippi Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Hg/m3)
Conf.
Int.
Autumn
Avg
(Hg/m3)
Conf.
Int.
Gulfport, Mississippi - GPMS
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Naphthalene
71
65
68
61
68
60
71
60
71
68
68
68
68
68
71
61
1.74
0.81
0.86
0.08
0.65
0.16
2.91
0.05
0.17
0.10
0.13
0.02
0.05
0.02
0.40
0.01
1.39
0.56
0.78
0.09
0.54
0.15
1.76
0.05
0.27
0.15
0.11
0.01
0.05
0.03
0.24
0.01
1.61
0.67
0.89
0.06
0.57
0.12
3.28
0.04
0.30
0.15
0.35
0.02
0.06
0.03
0.93
0.01
1.98
1.17
0.67
0.05
0.84
0.15
4.26
0.04
0.37
0.24
0.11
0.01
0.13
0.07
0.94
0.01
2.26
0.98
1.07
0.10
0.76
0.22
3.01
0.07
0.30
0.20
0.26
0.05
0.08
0.06
0.50
0.02
Tupelo, Mississippi - TUMS
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Tetrachloroethylene
61
47
60
47
60
36
61
33
61
60
60
60
60
60
61
60
1.95
0.62
0.76
0.06
0.65
0.10
1.58
0.29
0.24
0.13
0.20
0.01
0.04
0.02
0.26
0.15
1.30
0.31
0.68
0.06
0.54
NR
0.63
0.17
0.49
0.11
0.12
0.01
0.04
NR
0.14
0.18
2.15
0.71
1.06
0.04
0.58
NR
1.76
NR
0.44
0.35
0.68
0.02
0.04
NR
0.37
NR
2.46
0.42
0.49
0.04
0.75
0.07
2.88
0.11
0.36
0.10
0.08
0.01
0.12
0.02
0.41
0.06
1.93
0.61
0.82
0.07
0.73
0.13
1.13
0.25
0.43
0.20
0.30
0.04
0.07
0.04
0.23
0.19
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
-------
either the acute and intermediate risk values, and each site's non-chronic risk is summarized in
Table 16-4.
The following observations about acrolein are shown in Table 16-4:
• All of the acrolein measured detections at GPMS and TUMS exceeded the ATSDR
MRL acute value, and all but two acrolein measured detections at each site exceeded
the CALEPA REL value.
• All the seasonal averages for both sites were greater than the ATSDR intermediate
value (0.09 |ig/m3).
For the pollutants that exceeded the short-term (acute) risk factors, the concentrations
were further examined by developing pollution roses for these pollutants. A pollution rose is a
plot of concentration and wind direction. Acrolein exceeded the acute risk factors at both GPMS
and TUMS. Figures 16-5 through 16-6 are acrolein pollution roses for GPMS and TUMS. As
shown in Figures 16-5 through 16-6, and discussed above, all acrolein concentrations exceeded
at least one of the acute risk factors, which are indicated by a dashed line (CALEPA REL) and
solid line (ATSDR MRL).
Observations gleaned from the acrolein pollution rose for GPMS include:
• The pollution rose shows that acrolein concentrations exceeded the acute risk factors
on days with winds from a variety of directions. This tends to be a characteristic of
mobile sources.
• Several major thoroughfares through Gulfport are located near the monitoring site. In
addition, GPMS is located near the Gulfport-Biloxi Regional Airport.
Observations gleaned from the acrolein pollution rose for TUMS include:
• The pollution rose shows that concentrations exceeding the acute risk factors
occurred with winds originating from a variety of directions, which is characteristic
of mobile sources.
• The highest concentration of acrolein occurred with a north-northeasterly wind.
• TUMS is located on the Tupelo Airport property on the west side of town. Several
major roadways, such as Natchez Trace Parkway and Highway 278, border the airport
property.
16-11
-------
Table 16-4. Non-Chronic Risk Summary for the Mississippi Monitoring Sites
Site
GPMS
TUMS
Method
TO- 15
TO- 15
Pollutant
Acrolein
Acrolein
Daily
Average
(jig/m3)
0.81
±0.10
0.62
±0.13
ATSDR
Short-
term
MRL
(Hg/m3)
0.11
0.11
# of ATSDR
MRL
Exceedances
65
47
CAL
EPA
REL
Acute
(Hg/m3)
0.19
0.19
# of CAL
EPA REL
Exceedances
62
45
ATSDR
Intermediate
-term MRL
(Hg/m3)
0.09
0.09
Winter
Average
(jig/m3)
0.56
±0.15
0.31
±0.11
Spring
Average
(jig/m3)
0.67
±0.15
0.71
±0.35
Summer
Average
(jig/m3)
1.17
±0.24
0.42
±0.10
Autumn
Average
(jig/m3)
0.98
±0.20
0.61
±0.20
to
-------
Figure 16-5. Acrolein Pollution Rose for GPMS
3.0
2.5
2.0
1.5
1.0
£ 0.5
I
u
O 0.0
O
'c
re
3 0.5
"5
Q.
1.0
1.5
2.0
2.5
NW
W
•CAEPARELfO.IQijg/rrr1
-ATSDR MRL(0.11 |jg/m3
,***
•
• •
: 4
* »
* »;
NE
sw
Dailv Ava Cone =0.81 ±0.10 ua/m3
SE
3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5
Pollutant Concentration
1.0
1.5
2.0
2.5
3.0
-------
Figure 16-6. Acrolein Pollution Rose for TUMS
4.0
3.5
3.0
2.5
2.0
1.5
| 1'°
•£ 0.5
Ol
O 00
o
ra 0.5
'S
8. 1.0
1.5
2.0
2.5
3.0
3.5
4.0
NW , N
— CA EPA REL (0. 1 9 |jg/m3)
— ATSDR MRL(0.11 |jg/m3)
-
-
-
-
%_
W * t J
«0 - 'JV
» • T
-
-
-
-
C\A/ O
&vV o
NE
^
* *
«
^t * E
f' •
%
DailvAva Cone =0.62 ±0.13 ua/m3 SE
4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0
Pollutant Concentration
1.5
2.0
2.5
3.0
3.5
4.0
-------
16.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following three
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and the concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
16.4.1 Pearson Correlation Analysis
Table 16-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters at the Mississippi monitoring sites.
(Please refer to Section 3.1.6 for more information on understanding Pearson correlations.)
The following observations are gathered for GPMS from Table 16-5:
• Strong positive correlations were calculated between acrolein and carbon
tetrachloride and formaldehyde and maximum and average temperatures, indicating
that concentrations of these pollutants increase as temperatures increase.
• With the exception of benzene, the pollutants of interest exhibited negative
correlations with scalar wind speed. This indicates that concentrations tend to
increase as wind speeds decrease.
The following observations are gathered for TUMS from Table 16-5:
• Strong positive correlations were calculated for formaldehyde and maximum,
average, dew point, and wet bulb temperatures. This indicates that as temperatures
and moisture content increase, formaldehyde concentrations at TUMS also increase.
• A strong positive correlation was also calculated between acetaldehyde and relative
humidity, although this trend was not consistent across all three moisture variables.
16.4.2 Composite Back Trajectory Analysis
Figures 16-7 and 16-8 are composite back trajectory maps for the Mississippi monitoring
sites for the days on which sampling occurred. Each line represents the 24-hour trajectory along
which a parcel of air traveled toward the monitoring site on a sampling day. Each concentric
circle around the site in Figures 16-7 and 16-8 represents 100 miles.
16-15
-------
Table 16-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Mississippi
Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar Wind
Speed
Gulfport, Mississippi - GPMS
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Carbon Tetrachloride
Formaldehyde
Naphthalene
£>-Dichlorobenzene
61
71
65
68
68
71
60
60
-0.10
0.39
0.52
-0.01
0.51
0.47
-0.10
0.00
-0.17
0.27
0.46
-0.04
0.46
0.44
-0.23
-0.11
-0.09
0.13
0.41
-0.03
0.32
0.25
-0.28
-0.13
-0.14
0.18
0.44
-0.04
0.39
0.33
-0.27
-0.13
0.12
-0.21
0.06
-0.01
-0.14
-0.26
-0.20
-0.08
0.06
-0.02
-0.05
0.03
-0.16
-0.11
0.01
0.12
-0.03
-0.49
-0.42
0.26
-0.28
-0.33
-0.29
-0.27
Tupelo, Mississippi - TUMS
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Carbon Tetrachloride
Formaldehyde
£>-Dichlorobenzene
Tetrachloroethylene
47
61
47
60
60
61
36
33
-0.18
0.34
0.17
0.00
0.32
0.82
-0.12
-0.05
-0.28
0.24
0.21
-0.06
0.34
0.80
-0.22
-0.06
-0.31
0.05
0.28
-0.07
0.35
0.66
-0.19
-0.11
-0.30
0.15
0.26
-0.07
0.35
0.74
-0.22
-0.09
0.02
-0.53
0.14
-0.01
-0.03
-0.51
0.12
-0.14
0.12
0.41
-0.22
0.10
-0.04
-0.04
0.13
-0.19
-0.36
-0.37
-0.09
-0.20
-0.28
-0.37
-0.21
0.20
-------
Figure 16-7. Composite Back Trajectory Map for GPMS
-------
Figure 16-8. Composite Back Trajectory Map for TUMS
oo
-------
The following observations can be made from Figures 16-7:
• Back trajectories originated from a variety of directions at GPMS.
• The 24-hour airshed domain was somewhat larger at GPMS than at TUMS, with
trajectories originating as far away as Iowa (> 800 miles). However, nearly all of the
trajectories originated within 400 miles of GPMS.
The following observations can be made from Figures 16-8:
• Back trajectories also originated from a variety of directions at TUMS.
• The 24-hour airshed domain was slightly smaller at TUMS than GPMS, with the
longest trajectory originating just over 600 miles away. However, most of the
trajectories originated within 300 miles of the site.
16.4.3 Wind Rose Analysis
Hourly wind data from weather stations near these sites were uploaded into a wind rose
software program, WRPLOT (Lakes, 2006). WRPLOT produces a graphical wind rose from
submitted wind data. A wind rose shows the frequency of wind directions about a 16-point
compass, and uses different shading to represent wind speeds. Figures 16-9 and 16-10 are the
wind roses for the Mississippi monitoring sites on days that sampling occurred.
Observations from Figure 16-9 include:
• Hourly winds were predominantly out of the north (11 percent of observations) and
south (9 percent) on sampling days near GPMS.
• Calm winds (<2 knots) were recorded for 23 percent of the hourly measurements.
• Most of the observations ranged from 7 to 11 knots, although winds greater than 17
knots occurred most frequently with east-southeasterly or southeasterly winds.
Observations from Figure 16-10 include:
• Similar to GPMS, hourly winds were predominantly out of the north (15 percent of
observations) and south (13 percent) on sampling days near TUMS.
• Calm winds (<2 knots) were recorded for 21 percent of the hourly measurements.
16-19
-------
Figure 16-9. Wind Rose for GPMS Sampling Days
WEST
to
o
SOUTH,-'
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
• 11 - 17
^| 7- 11
I I A- 7
H 2- 4
Calms: 22.84%
-------
Figure 16-10. Wind Rose for TUMS Sampling Days
WEST
to
SOUTH,-'
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
• 11 - 17
^| 7- 11
I I 4- 7
^| 2- 4
Calm;: 20.59%
-------
• Wind speeds ranging from 7 to 11 knots were the most frequently observed wind
speed (32 percent of observations).
16.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; BTEX analysis; and
ethylene-acetylene ratio analysis.
16.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population information for Harrison and Lee
County, Mississippi, were obtained from the Mississippi State Tax Commission and the U.S.
Census Bureau, and are summarized in Table 16-6. Table 16-6 also includes a vehicle
registration to county population ratio (vehicles per person). In addition, the population within
10 miles of each site is presented. An estimation of 10-mile vehicle registration was computed
using the 10-mile population surrounding the monitor and the vehicle registration ratio. Finally,
Table 16-6 contains the average daily traffic information, which represents the average number
of vehicles passing the monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 16-6 include:
• Population, vehicle registration, and traffic volume are higher near GPMS then
TUMS.
• Both sites are in the lowest third for population and vehicle ownership compared to
other UATMP sites.
• The GPMS vehicles per person estimate ranks thirteenth for all UATMP sites.
16.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compares them to the
16-22
-------
Table 16-6. Motor Vehicle Information for the Mississippi Monitoring Sites
Site
GPMS
TUMS
2006 Estimated
County
Population
171,875
79,714
Number of
Vehicles
Registered
171,674
69,888
Vehicles per Person
(Registration:
Population)
1.00
0.88
Population
Within 10 Miles
173,435
71,184
Estimated 10 Mile
Vehicle Ownership
173,232
62,409
Traffic Data
(Daily Average)
17,000
4,900
to
-------
concentration ratios at each of the monitoring sites in an effort characterize the impact of on-
road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• The toluene-ethylbenzene ratio was the highest ratio for both GPMS and TUMS (6.89
± 0.55 and 9.47 ± 0.95, respectively), and both were significantly higher than the
toluene-ethylbenzene ratio for the roadside study (5.85).
• For both GPMS and TUMS, the benzene-ethylbenzene ratio was higher than the
xylene-ethylbenzene ratio, which is the opposite of the roadside study.
16.5.3 Mobile Tracer Analysis
As previously stated, GPMS sampled for SNMOC in addition to VOC. Acetylene is a
pollutant that is primarily emitted from mobile sources, while ethylene is emitted from mobile
sources, petroleum refining facilities, and natural gas distribution facilities. Tunnel studies
conducted on mobile sources have found that concentrations of ethylene and acetylene are
typically present in a 1.7 to 1 ratio. (For more information, please refer to Section 3.2.1.3.)
The ethylene to acetylene ratio for GPMS is provided in Table 3-11.
Table 3-11 shows:
• GPMS's ethylene-acetylene ratio (1.47) was somewhat lower than the 1.7 ratio.
• This ratio suggests that while mobile sources may be influencing the air quality at the
GPMS monitoring site, there may also be atmospheric chemical processes affecting
the quantities of ethylene in this area's air quality.
• Known sinks of ethylene include reactions with ozone, as well as soil (NLMb).
16.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. Figures
16-11 and 16-12 present the trends graphs for formaldehyde, benzene, and 1,3-butadiene for
GPMS and TUMS, respectively.
16-24
-------
The following observations can be made from Figures 16-11 and 16-12:
• The GPMS monitoring site has participated in the UATMP since 2001. After several
years of decreasing, formaldehyde concentrations increased in 2005 which continued
in 2006. Hurricane Katrina devastated the Gulf Coast on August 29, 2005, which
could account for this increase. Benzene's average concentration also increased in
2005, but returned to 2004 levels in 2006. 1,3-Butadiene's 2006 average was the
lowest of all sampling years at GPMS.
• TOMS' formaldehyde concentrations have been decreasing since 2001, as depicted in
Figure 16-12. The 1,3-butadiene and benzene concentrations have not changed
significantly since 2001 at TUMS.
16.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Mississippi sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 16-7.
Additionally, the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA were
retrieved and are also presented in Table 16-7. The NATA data are presented for the census tract
where each monitoring site is located.
The census tract information for the Mississippi sites is as follows:
• The census tract for GPMS is 28047001700, which had a population of 6,200 and
represents approximately 3.3 percent of the Harrison County population in 2000.
• The census tract for TUMS is 280081950600, which had a population of 7,862, and
represents approximately 10 percent of the Lee County population in 2000.
The following observations can be made for GPMS from Table 16-7:
• The pollutants with the top three annual averages by mass concentration at GPMS
were formaldehyde (2.91 ± 0.40 |ig/m3), xylenes (2.05 ± 0.45 |ig/m3), and
acetaldehyde (1.74 ± 0.17 |ig/m3).
16-25
-------
Figure 16-11. Comparison of Yearly Averages for the GPMS Monitoring Site
.Q
a.
a.
o
o
o
O)
0 -I—
2001
2002
2003
2004
2005
2006
Year
ni,3-Butadiene
I Benzene
D Formaldehyde
-------
7 -
6
.a
a.
3 5
o
to
o
o
-------
Table 16-7. Chronic Risk Summary for the Monitoring Sites in Mississippi
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk
(HQ)
2006 UATMP
Annual
Average
(Hg/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk
(HQ)
Gulfport, Mississippi (GPMS) - Census Tract ID 28047001700
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
1 ,4-Dichlorobenzene
p-Dichlorobenzene
Dichloromethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Naphthalene
Tetrachloroethylene
Xylenes
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
0.000011
0.00000047
5.5E-09
0.000022
0.000034
0.0000059
NR
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
0.8
1
0.0098
0.09
0.003
0.27
0.1
0.98
0.06
0.01
0.90
0.07
0.21
0.02
0.02
0.29
0.97
O.01
0.03
0.12
1.72
2.17
NR
0.02
7.02
2.00
3.17
0.23
0.23
0.14
0.01
0.03
0.86
0.70
NR
0.11
2.97
0.01
0.03
0.03
0.01
O.01
0.01
O.01
0.10
O.01
0.01
0.01
0.02
1.74 ±0.17
0.78 ±0.10
0.07 ± 0.02
0.86 ±0.13
0.08 ±0.01
0.65 ±0.05
0.03 ±0.01
0.16 ±0.02
0.43 ±0.09
2.91 ±0.40
0.33 ±0.14
NA
0.15 ±0.09
2.05 ±0.45
3.84
NR
4.46
6.70
2.33
9.70
0.29
1.75
0.20
0.02
7.15
NA
0.88
NR
0.19
39.13
0.03
0.03
0.04
0.02
O.01
0.01
O.01
0.30
O.01
NA
0.01
0.02
Tupelo, Mississippi (TUMS) - Census Tract ID 28081950600
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
0.000026
5.5E-09
0.000022
0.0000059
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
2.4
0.0098
0.09
0.27
0.82
0.04
0.01
0.9
0.05
0.21
0.02
0.02
0.76
0.01
0.07
1.81
NR
0.01
7.06
1.55
3.14
0.22
0.41
O.01
0.03
0.39
0.09
2.06
0.01
0.03
0.03
0.01
O.01
0.01
0.08
0.01
0.01
1.95 ±0.24
0.51 ±0.12
0.07 ±0.01
0.76 ± 0.20
0.05 ±0.01
0.65 ±0.04
0.08 ±0.02
0.03 ±0.01
1.58 ±0.26
0.22 ±0.12
0.18 ±0.09
4.29
NR
4.54
5.94
1.61
9.76
0.90
0.90
0.01
4.80
1.07
0.22
25.67
0.03
0.03
0.03
0.02
O.01
0.01
0.16
0.01
0.01
to
oo
BOLD indicates a pollutant of interest
NA = no annual average available
NR = a risk factor is not available and therefore, no risk calculation can be made
-------
• The pollutants with the highest cancer risks were not these pollutants. The highest
theoretical cancer risks for GPMS were calculated for carbon tetrachloride (9.70 in-a-
million), hexachloro-1,3-butadiene (7.15), and benzene (6.70).
• According to the 1999 NAT A, formaldehyde, xylenes, and acetaldehyde also had the
highest modeled concentrations, but benzene, carbon tetrachloride, and acetaldehyde
had the highest cancer risk for pollutants that failed screens at GPMS.
• Acrolein was the only pollutant that exhibited a noncancer HQ greater than 1,
according to both the 2006 annual average-based noncancer risk and the 1999 NATA.
But the 2006 annual average-based noncancer risk for acrolein (39.13) was
significantly higher than the NATA modeled noncancer risk (2.97).
• All other noncancer HQs were less than 0.35.
• No annual average, and therefore no theoretical cancer and noncancer risks, are
available for naphthalene because GPMS stopped sampling SVOC in October.
The following observations can be made for TUMS from Table 16-7:
• The pollutants with the top three annual averages by mass concentration at TUMS
were acetaldehyde (1.95 ± 0.24 |ig/m3), formaldehyde (1.58 ± 0.26 |ig/m3), and
benzene (0.76 ± 0.20 |ig/m3), which also had the highest NATA-modeled
concentrations.
• The highest theoretical cancer risks calculated from the annual averages for TUMS
were carbon tetrachloride (9.76 in-a-million), benzene (5.94), and acrylonitrile (4.54),
while the highest NATA cancer risks were modeled for benzene (7.06), carbon
tetrachloride (3.14), and acetaldehyde (1.81).
• Acrolein was the only pollutant that exhibited a noncancer HQ greater than 1,
according to both the 2006 annual average-based noncancer risk and the 1999 NATA.
But, similar to GPMS, the 2006 annual average-based noncancer risk for acrolein
(25.67) was significantly higher than the NATA modeled noncancer risk (2.06).
• All other noncancer HQs were less than 0.30.
16.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 16-8 and 16-9 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 16-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
16-29
-------
Table 16-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Mississippi
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer Risk
(in-a-million)
Gulfport, Mississippi (GPMS) - Harrison County
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Tetrachloroethylene
Naphthalene
1 ,4-Dichlorobenzene/
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15 -PAH
Trichloroethylene
259.68
72.47
29.74
24.27
16.46
16.06
5.19
4.09
1.44
1.28
Benzene
1,3 -Butadiene
Lead
Naphthalene
Polycyclic Organic Matter as 7-PAH
Arsenic
Tetrachloroethylene
Polycyclic Organic Matter as
15-PAH
Acetaldehyde
Hexavalent Chromium
2.03E-03
7.28E-04
4.26E-04
1.76E-04
l.OOE-04
9.50E-05
9.47E-05
7.92E-05
6.54E-05
5.94E-05
Carbon Tetrachloride
Hexachloro- 1 ,3 -butadiene
Benzene
Acrylonitrile
Acetaldehyde
1,3 -Butadiene
£>-Dichlorobenzene
Tetrachloroethylene
1 ,4-Dichlorobenzene
Dichloromethane
9.70
7.15
6.70
4.46
3.84
2.33
1.75
0.88
0.29
0.20
Tupelo, Mississippi (TUMS) - Lee County
Dichloromethane
Benzene
Formaldehyde
Acetaldehyde
Naphthalene
1,3 -Butadiene
Tetrachloroethylene
Trichloroethylene
1 ,4-Dichlorobenzene
Nickel
213.37
125.72
31.69
11.52
10.27
9.35
6.30
2.45
1.66
0.88
Hexavalent Chromium
Benzene
Lead
Naphthalene
1,3 -Butadiene
Nickel
Arsenic
Dichloromethane
Cadmium
Polycyclic Organic Matter as 7-PAH
2.42E-03
9.81E-04
3.85E-04
3.49E-04
2.81E-04
1.41E-04
1.13E-04
l.OOE-04
9.86E-05
5.37E-05
Carbon Tetrachloride
Benzene
Hexachloro- 1 ,3 -butadiene
Acrylonitrile
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
1 ,2-Dichloroethane
£>-Dichlorobenzene
Formaldehyde
9.76
5.94
4.80
4.54
4.29
1.61
1.07
0.90
0.90
0.01
-------
the highest cancer risk (in-a-million) as calculated from the annual average. Table 16-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. GPMS sampled for VOC, SNMOC, SVOC, and carbonyl compounds.
However, GPMS stopped sampling for SVOC prior to November, so no annual average, and thus
cancer and noncancer risk values, could be calculated. TUMS sampled for VOC and carbonyl
compounds only. In addition, the highest cancer and noncancer risks based on annual averages
are limited to those pollutants failing at least one screen.
The following observations can be made for GPMS from Table 16-8:
• Benzene was the highest emitted pollutant with a cancer risk factor, had the highest
cancer toxicity-weighted emissions, and had the third highest cancer risk based on the
2006 annual average for GPMS.
• Carbon tetrachloride and hexachloro-1,3-butadiene had the highest cancer risks based
on the 2006 annual average; however, these pollutants were neither emitted in high
quantities nor toxic based on the 2002 NEI emission inventory.
• Benzene, tetrachloroethylene, acetaldehyde, and 1,3-butadiene were shown on all
three "top 10" lists.
The following observations can be made for TUMS from Table 16-8:
• While benzene was most commonly the highest emitted pollutant (by mass) with a
cancer risk factor and had the highest cancer toxicity-weighted emissions in many
UATMP counties, this was not the case for Lee County, Mississippi.
• Dichloromethane was the highest emitted pollutant, and this pollutant had the eighth
highest cancer toxicity-weighted emissions. Hexavalent chromium, which did not
have one of the 10 highest emissions in Lee County, had the highest cancer toxicity-
weighted emissions. This indicates that hexavalent chromium has a relatively high
toxicity.
16-31
-------
Table 16-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for
the Monitoring Sites in Mississippi
Top 10 Total Emissions for Pollutants
with Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted
Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on Annual
Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk
(HQ)
Gulfport, Mississippi (GPMS) - Harrison County
Xylenes
Hydrochloric Acid
Toluene
Benzene
Ethylbenzene
Hexane
Methanol
Methyl Ethyl Ketone
Hydrogen Fluoride
Formaldehyde
1,074.93
1,034.43
827.86
259.68
231.08
194.60
123.37
98.22
78.09
72.47
Acrolein
Hydrochloric Acid
Chlorine
1,3 -Butadiene
Xylenes
Manganese
Benzene
Formaldehyde
Nickel
Cyanide
257,453.61
51,721.52
16,950.00
12,135.88
10,749.27
10,155.93
8,655.88
7,394.69
4,358.15
4,251.04
Acrolein
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Acrylonitrile
Benzene
Xylenes
Carbon Tetrachloride
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
39.13
0.30
0.19
0.04
0.03
0.03
0.02
0.02
0.00
0.00
Tupelo, Mississippi (TUMS) - Lee County
Toluene
Xylenes
Dichloromethane
Methyl Isobutyl Ketone
Benzene
Methyl Ethyl Ketone
Glycol Ethers
Methanol
Hexane
Ethylbenzene
308.12
216.58
213.37
199.44
125.72
104.00
63.81
55.61
48.66
39.37
Acrolein
Nickel
1,3 -Butadiene
Benzene
2,4-Toluene Diisocyanate
Naphthalene
Formaldehyde
Manganese
Glycol Ethers
Cadmium
94,615.93
13,509.96
4,676.76
4,190.76
4,091.84
3,424.92
3,233.42
3,193.98
3,190.27
2,739.45
Acrolein
Acetaldehyde
Formaldehyde
Acrylonitrile
1,3 -Butadiene
Benzene
Carbon Tetrachloride
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
/>-Dichlorobenzene
25.67
0.22
0.16
0.03
0.03
0.03
0.02
0.00
0.00
0.00
to
-------
• Like GPMS, carbon tetrachloride had the highest cancer risk based on the 2006
annual average for TUMS, yet this pollutant was neither one of the highest emitted
nor one of the most toxic based on the 2002 NEI emission inventory.
The following observations can be made for GPMS from Table 16-9:
• Xylenes, hydrochloric acid, and toluene were the highest emitted pollutants (by mass)
with noncancer risk factors in Harrison County.
• Both xylenes and hydrochloric acid were among the top 10 based on toxicity-
weighted emissions.
• Although xylenes ranked seventh for GPMS for annual average-based noncancer risk,
the HQ was very low (0.02). Hydrochloric acid was not sampled for at GPMS.
• Acrolein had the highest noncancer toxicity-weighted emissions in Harrison County
and had the highest noncancer risk based on the 2006 annual average for GPMS, but
did not appear in the list of highest emitted pollutants.
• Benzene, xylenes, and formaldehyde appeared on all three top 10 lists.
The following observations can be made for TUMS from Table 16-9:
• Although toluene and xylenes were the highest emitted pollutants with noncancer risk
factors in Lee County, they did not rank in the top 10 based on toxicity-weighted
emissions.
• Both of these pollutants were sampled for at TUMS, yet neither was listed as having
one of the top 10 noncancer risks.
• Acrolein had the highest noncancer toxicity-weighted emissions in Lee County and
had the highest noncancer risk based on the 2006 annual average for TUMS, but did
not appear in the list of highest emitted pollutants.
16-33
-------
Mississippi Pollutant Summary
• The pollutants of interest common to each Mississippi site were acetaldehyde, benzene,
carbon tetrachloride, formaldehyde, acrolein, 1,3'-butadiene andp-dichlorobenzene.
• Acetaldehyde had the highest daily average at TUMS, while formaldehyde was highest at
GPMS.
• Acrolein was the only pollutant to exceed either of the short-term risk factors.
• A comparison of formaldehyde, benzene and 1,3-butadiene concentrations for all years of
UATMP participation shows that concentrations of formaldehyde and benzene increased
in 2005 from previous level at GPMS. Formaldehyde concentrations at TUMS have
remained constant over the last few years after steadily decreasing from 2001 through
2003.
16-34
-------
17.0 Site in Missouri
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Missouri (S4MO). This site is located in the St. Louis MSA. Figure 17-1 is a
topographical map showing the monitoring site in its urban location. Figure 17-2 identifies point
source emission locations within 10 miles of the site that reported to the 2002 NEI for point
sources. Numerous sources are located near the St. Louis site, most of which are involved in fuel
combustion industries.
St. Louis has a climate that is continental in nature, with cold, dry winters, warm,
somewhat wetter summers, and significant seasonal variability. Wind speeds are generally light
and wind flows from the southeast on average (Ruffner and Bair, 1987).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the S4MO monitoring site is at St. Louis Downtown Airport (WBAN 03960). Table 17-1
presents average meteorological conditions of temperature (average maximum and average),
moisture (average dew point temperature, average wet-bulb temperature, and average relative
humidity), pressure (average sea level pressure), and wind information (average scalar wind
speed) for the entire year and on days samples were collected. Also included in Table 17-1 is the
95 percent confidence interval for each parameter. As shown in Table 17-1, average
meteorological conditions on sampling days were fairly representative of average weather
conditions throughout the year.
17.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Michigan
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
17-1
-------
Figure 17-1. St. Louis, Missouri (S4MO) Monitoring Site
Source : USGS 7.5 Minute Series. Map Scale: 1:24,000.
17-2
-------
Figure 17-2. Facilities Located Within 10 Miles of S4MO
St. Louis
County
Mad i SOT
County
R >
P •.
p 5. j o
B
; p '•
' ' St. LOUIS ,
P/ i City "
p.
pp
P
pp
.
St.Clali
County
Legend
lir- S4MO UTAMP site
10 mile radius
Source Category Group (No. of Facilities)
* Agricultural Chemicals Production Industrial Facility (1)
* Automotive Repair, Services, & Parking (1)
'•- Business Services Facility (2)
c Chemicals & Allied Products Facility (10)
Z Electrical & Electronic Equipment Facility (1)
" Engineering & Management Services Facility (1)
D Fabricated Metal Products Facility (3)
G Food S Kindred Products Facility (1)
F Fuel Combustion Industrial Facility (51)
-t- Health Services Facility (1)
I Incineration Industrial Facility (1)
J Industrial Machinery 8 Equipment Facility (2)
t Integrated Iron & Steel Manufacturing Facility (2)
L Liquids Distribution Industrial Facility (10)
B Mineral Products Processing Industrial Facility (2)
P Miscellaneous Processes Industrial Facility (60)
Nose; Due to facility density and collocation, the total facilities
displayed may noi represent aH facilities within She area of interest
County boundary
-- Motor Freight Transportation & Warehousing (1)
i Non-ferrous Metals Processing Industrial Facility (6)
o Personal Services (7)
P Petroleum/Nat. Gas Prod. S Refining Industrial Facility (2)
> Pharmaceutical Production Processes Industrial Facility (3)
o Primary Metal Industries Facility (2)
R Printing & Publishing Facility (3)
4 Production of Organic Chemicals Industrial Facility (7)
» Railroad Transportation (1)
Y Rubber 8 Miscellaneous Plastic Products Facility (2)
u Stone. Clay, Glass, & Concrete Products (5)
s Surface Coating Processes Industrial Facility (12)
8 Utility Boilers (2)
Waste Treatment & Disposal Industrial Facility (4)
f Wholesale Trade (2)
S Wholesale Trade - Durable Goods (2)
* Wood Furniture Facility (1)
17-3
-------
Table 17-1. Average Meteorological Conditions near the Monitoring Site in Missouri
Site
S4MO
WBAN
03960
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
67.50
±1.86
68.14
±4.23
Average
Temperature
(°F)
57.25
±1.72
57.91
±3.88
Average
Dew Point
Temperature
(op)
45.63
±1.74
46.63
±3.75
Average
Wet Bulb
Temperature
(»F)
51.23
±1.57
51.92
±3.48
Average
Relative
Humidity
(%)
68.36
±1.18
69.27
±2.57
Average
Sea Level
Pressure
(mb)
1016.79
±0.73
1016.75
±1.33
Average
Scalar Wind
Speed
(kt)
6.28
±0.29
6.08
±0.71
-------
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. S4MO sampled for carbonyls, VOC,
hexavalent chromium, and metals Table 17-2 presents the nineteen pollutants that failed at least
one screen at S4MO.
Table 17-2. Comparison of Measured Concentrations and EPA Screening Values for the
Missouri Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
St. Louis, Missouri - S4MO
Acetaldehyde
Carbon Tetrachloride
Benzene
Arsenic (PM10)
Manganese (PM10)
1,3 -Butadiene
Formaldehyde
Acrolein
Cadmium (PM10)
Tetrachloroethylene
£>-Dichlorobenzene
Hexachloro- 1 , 3 -butadiene
Hexavalent Chromium
Nickel (PM10)
Acrylonitrile
1 ,2-Dichloroethane
Chloromethylbenzene
1 , 1 ,2,2-Tetrachloroethane
Trichloroethylene
Total
61
59
59
59
50
49
49
41
29
26
25
7
4
o
3
2
2
1
1
1
528
61
59
59
59
59
51
61
41
59
49
45
7
50
59
2
2
1
1
26
751
100.00
100.00
100.00
100.00
84.75
96.08
80.33
100.00
49.15
53.06
55.56
100.00
8.00
5.08
100.00
100.00
100.00
100.00
3.85
70.31
11.55
11.17
11.17
11.17
9.47
9.28
9.28
7.77
5.49
4.92
4.73
1.33
0.76
0.57
0.38
0.38
0.19
0.19
0.19
11.55
22.73
33.90
45.08
54.55
63.83
73.11
80.87
86.36
91.29
96.02
97.35
98.11
98.67
99.05
99.43
99.62
99.81
100.00
The following observations are shown in Table 17-2:
• A total of 528 measured concentrations failed screens.
The screening process at S4MO resulted in eleven pollutants of interest:
acetaldehyde (61 failed screens), arsenic (59), benzene (59), carbon tetrachloride (59),
17-5
-------
manganese (50), formaldehyde (49), 1,3-butadiene (49), acrolein (41), cadmium (29),
tetrachloroethylene (26), and/>-dichlorobenzene (25).
• Of the eleven pollutants of interest, acetaldehyde, acrolein, arsenic, benzene, and
carbon tetrachloride had 100 percent of their measured detections fail the screening
values.
17.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 17-3. Annual averages are presented and discussed in further detail in later
sections.
The following observations are shown in Table 17-3:
• Formaldehyde had the highest concentration by mass (3.19 ± 0.66 |ig/m3), followed
by acetaldehyde (2.95 ± 0.58 |ig/m3) and benzene (0.91 ± 0.16 |ig/m3).
• Formaldehyde concentrations were significantly higher in summer, while
acetaldehyde concentrations were highest in the spring. The remaining
concentrations did not vary much by season.
• Acetaldehyde, arsenic, benzene, cadmium, carbon tetrachloride, formaldehyde, and
manganese were detected in every sample collected at S4MO.
17-6
-------
Table 17-3. Daily and Seasonal Averages for the Pollutants of Interest for the Missouri Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Ug/m3)
Conf.
Int.
Autumn
Avg
(Ug/m3)
Conf.
Int.
St. Louis, Missouri - S4MO
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Cadmium (PM10)
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Manganese (PM10)
Tetrachloroethylene
61
41
59
59
51
59
59
45
61
59
49
61
59
59
59
59
59
59
59
61
59
59
2.95
0.78
<0.01
0.91
0.11
0.01
0.63
0.29
3.19
0.02
0.20
0.58
0.19
O.01
0.16
0.03
0.01
0.05
0.10
0.66
O.01
0.03
3.41
0.31
O.01
1.03
0.10
O.01
0.48
0.09
1.41
0.01
0.17
1.28
0.12
O.01
0.46
0.05
O.01
0.06
0.08
0.51
0.01
0.06
4.18
NR
O.01
0.78
0.07
O.01
0.58
0.17
1.77
0.02
0.15
1.64
NR
O.01
0.18
0.04
O.01
0.10
0.17
0.71
0.01
0.06
2.21
0.73
O.01
0.70
0.06
O.01
0.73
0.37
6.82
0.01
0.17
0.22
0.26
O.01
0.10
0.01
O.01
0.12
0.21
1.11
O.01
0.03
1.97
0.96
O.01
1.12
0.16
O.01
0.72
0.30
2.86
0.02
0.22
0.26
0.47
O.01
0.27
0.07
O.01
0.10
0.14
0.62
0.01
0.08
NR = Not reportable due to the low number of measured detections.
-------
17.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for S4MO was evaluated using ATSDR
short-term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is
defined as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15
to 364 days. It is useful to compare the preprocessed daily measurements to the short-term MRL
and REL factors, as well as compare seasonal averages to the intermediate MRL. Of the
nineteen pollutants with at least one failed screen, only acrolein exceeded the acute risk values,
and its non-chronic risk is summarized in Table 17-4.
The following observations about acrolein are shown in Table 17-4:
• All forty-one acrolein measured detections were greater than the ATSDR MRL acute
risk value of 0.11 |ig/m3 and 39 were greater than the California EPA REL value of
0.19|ig/m3.
• The average measured concentration was 0.78 ±0.19 |ig/m3, which is more than four
times the California REL value.
• A valid seasonal average could not be calculated for spring due to the low number of
measured detections.
• The remaining seasonal averages ranged from more than three to over 10 times the
ATSDR intermediate risk MRL.
For the pollutants that exceeded the short-term (acute) risk factors, the concentrations
were further examined by developing pollution roses for these pollutants. A pollution rose is a
plot of daily concentration and daily average wind direction. Figure 17-3 is a pollution rose for
acrolein at S4MO.
Observations gleaned from the acrolein pollution rose include:
• All of the acrolein concentrations exceeded the ATSDR MRL acute risk factor,
indicated by a solid line, and all but two exceeded the CalEPA REL, indicated by a
dashed line.
• The concentrations on the pollution rose are scattered around the center, a pattern
characteristic of mobile sources.
17-8
-------
Table 17-4. Non-Chronic Risk Summary for the Missouri Monitoring Site
Site
S4MO
Method
TO- 15
Pollutant
Acrolein
Daily
Average
(ug/m3)
0.78 ±0.19
ATSDR
Short-term
MRL
(ug/m3)
0.11
# of ATSDR
MRL
Exceedances
41
CAL EPA
REL
Acute
(ug/m3)
0.19
# of CAL
EPA REL
Exceedances
39
ATSDR
Intermediate-
term MRL
(Ug/m3)
0.09
Winter
Average
(Ug/m3)
0.31
±0.12
Spring
Average
(Ug/m3)
NR
Summer
Average
(Ug/m3)
0.73
±0.26
Autumn
Average
(Ug/m3)
0.96
±0.47
NR = Not reportable due to the low number of measured detections.
-------
Figure 17-3. Acrolein Pollution Rose for S4MO
4.5
4.0
3.5
3.0
2.5
2.0
1.5
c
.2 1.0
'!B
c 0.5
a
u
^
ir fi fi
O u.u
O
1 0.5
3
_=
•5 1.0
Q.
1.5
2.0
2.5
3.0
3.5
4.0
AX.
NW N
— CA EPA REL (0. 1 9 pg/m3)
— ATSDR MRL (0.11 |jg/m3)
-
-
-
-
-
^
^ _
W * * * «!
^ ^?*
* * <
^
-
-
-
-
-
-
O\AI O
ovv o
________________________^^
NE
^
•
^ ^
t^ E
' ~ &*
^F A ^
^
—
I »
•
•
Daily Avq Cone =0.78 ±0.1 9 uq/m3 SE
3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
Pollutant Concentration
-------
The highest concentration of acrolein was measured on a day with an east-
southeasterly wind. A number of fuel combustion emission sources are located in the
same general direction.
S4MO is located in downtown St. Louis, between 1-70 and another major roadway.
17.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
17.4.1 Pearson Correlation Analysis
Table 17-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters at the S4MO monitoring site. (Please
refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered from Table 17-5:
• Formaldehyde exhibited strong positive correlations with maximum, average, dew
point and wet bulb temperatures, which indicates that formaldehyde concentrations
increase as temperature and moisture content increase.
• Carbon tetrachloride also exhibited strong positive correlations with maximum and
average temperature.
• All of the correlations between the pollutants of interest and scalar wind speed were
negative, indicating that as wind speeds decrease, concentrations increase.
• The remaining correlations were generally weak.
17.4.2 Composite Back Trajectory Analysis
Figure 17-4 is a composite back trajectory map for the S4MO monitoring site for the days
on which sampling occurred. Each line represents the 24-hour trajectory along which a parcel of
air traveled toward the monitoring site on a sampling day. Each concentric circle around the site
in Figure 17-4 represents 100 miles.
17-11
-------
Table 17-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Missouri Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
St. Louis, Missouri - S4MO
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Cadmium (PM10)
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Manganese (PM10)
Tetrachloroethylene
61
41
59
59
51
59
59
45
61
59
49
0.03
0.22
-0.03
-0.04
-0.12
0.28
0.52
0.20
0.76
0.07
0.25
-0.07
0.18
-0.13
-0.17
-0.24
0.22
0.50
0.18
0.75
0.04
0.09
-0.13
0.21
-0.13
-0.18
-0.26
0.18
0.47
0.18
0.70
-0.05
0.04
-0.10
0.20
-0.13
-0.18
-0.24
0.21
0.48
0.18
0.73
-0.01
0.07
-0.18
0.12
0.05
0.02
-0.01
-0.11
-0.07
0.05
-0.14
-0.30
-0.09
-0.09
-0.16
0.14
-0.07
-0.08
0.00
-0.06
-0.08
0.02
-0.01
-0.02
-0.19
-0.34
-0.36
-0.37
-0.31
-0.44
-0.37
-0.30
-0.49
-0.10
-0.50
to
-------
Figure 17-4. Composite Back Trajectory Map for S4MO
-------
The following observations can be made from Figure 17-4:
• Back trajectories originated from a variety of directions at S4MO, although there
an apparent lack of trajectories from the east.
was
The 24-hour airshed domain was very large at S4MO, with trajectories originating as
far away as western Ontario, Canada (> 800 miles).
The majority of the trajectories originated within 400 miles of the site.
17.4.3 Wind Rose Analysis
Hourly wind data from the St. Louis Downtown Airport near the S4MO monitoring site
were uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces
a graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
about a 16-point compass, and uses different shading to represent wind speeds. Figure 17-5 is
the wind rose for the S4MO monitoring site on days that sampling occurred.
Observations from Figure 17-5 include:
• Hourly winds were predominantly out of the southeast (12 percent), south-southeast
(11 percent of observations), and south (10 percent), on sampling days.
• Wind speeds commonly ranged from 7 to 11 knots on sampling days.
• Calm winds (<2 knots) were observed for 19 percent of the measurements.
17.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as this site did not sample for SNMOC.
17.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in St. Louis City and St. Louis County,
Missouri were obtained from the Missouri Department of Revenue and the U.S. Census Bureau,
and are summarized in Table 17-6. Table 17-6 also includes a vehicle registration to county
population ratio (vehicles per person). In addition, the population within 10 miles of each site is
17-14
-------
Figure 17-5. Wind Rose for S4MO Sampling Days
NORTH"---.
15%
SOUTH .--'
WIND SPEED
(Knots)
I | >=22
I I 17 - 21
• 11 - 17
I I A- 7
^| 2- 4
Calms: 13.90%
-------
Table 17-6. Motor Vehicle Information for the Missouri Monitoring Site
Site
S4MO
2006 Estimated
County
Population
1,347,691
Number of
Vehicles
Registered
1,438,244
Vehicles per Person
(Registration:
Population)
1.07
Population
Within 10 Miles
821,898
Estimated 10 Mile
Vehicle Ownership
877,122
Traffic Data
(Daily Average)
22,840
-------
presented. An estimation of 10-mile vehicle registration was computed using the 10-mile
population surrounding the monitor and the vehicle registration ratio. Finally, Table 17-6
contains the average daily traffic information, which represents the average number of vehicles
passing the monitoring sites on the nearest roadway to each site on a daily basis
Observations gleaned from Table 17-6 include:
• Compared to other UATMP sites, S4MO has the 7th highest county population and
the 8th highest county-level vehicle registration count.
• S4MO also has the 10th highest estimated vehicle registration-to-population ratio.
• The average daily traffic count falls in the middle of the range compared to other
UATMP sites.
• The S4MO monitoring site is in a residential area and is located in an urban-city
center setting.
17.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compares them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• The toluene-ethylbenzene ratio (5.73 ± 0.58, respectively) was very similar to that of
the roadside study (5.85).
• But unlike the roadside study, the benzene-ethylbenzene ratio (3.55 ± 0.43) was
higher than the xylenes-ethylbenzene ratio (2.80 ± 0.20).
17.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
17-17
-------
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. S4MO
has been a participant in the UATMP since 2002. Figure 17-6 presents the trends analysis for
formaldehyde, benzene, and 1,3-butadiene for S4MO. Based on Figure 17-6, the following
observations were made:
• The average benzene concentration decreased slightly in 2006.
• S4MO's 1,3-butadiene concentrations have been decreasing since 2004, although
difficult to discern in Figure 17-6.
• When the confidence intervals, represented by the error bars, are taken into account,
formaldehyde concentrations have changed little over the period, although a slight
downward trend seems likely.
17.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
S4MO and where the annual average concentrations could be calculated (refer to Section 3.3.5
regarding the definition of an annual average). Annual averages, theoretical cancer and
noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 17-7. Additionally,
the pollutants of interest are bolded. In addition to the annual averages and risks based on 2006
monitoring data, data from EPA's 1999 NAT A were retrieved and are also presented in Table
17-7. The NATA data are presented for the census tract where the monitoring site is located.
The census tract information for the Missouri monitoring site is as follows:
• The census tract for S4MO is 29510109700.
• The population for this census tract was 4,016, which represents approximately 0.3
percent of the St. Louis County population in 2000.
The following observations, based on the annual averages, can be made from Table 17-7:
• The pollutants with the top 3 annual averages by mass concentration at S4MO were
formaldehyde (3.19 ± 0.66 |ig/m3), acetaldehyde (2.95 ± 0.58 |ig/m3), and benzene
(0.91±0.16|ig/m3).
17-18
-------
Figure 17-6. Comparison of Yearly Averages for the S4MO Monitoring Site
Q.
Q.
O
4-1
us
O
o
o
O)
5
<5
2002
2003
2004
Year
2005
2006
D1,3-Butadiene
I Benzene
D Formaldehyde
-------
Table 17-7. Chronic Risk Summary for the Monitoring Site in Missouri
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Ug/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual Average
(Ug/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
St. Louis, Missouri (S4MO) - Census Tract ID 29510109700
Acetaldehyde
Acrolein
Acrylonitrile
Arsenic*
Benzene
1,3-Butadiene
Cadmium*
Carbon Tetrachloride
Chloromethylbenzene
p-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Hexavalent Chromium
Manganese*
Nickel*
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Trichloroethylene
0.0000022
NR
0.000068
0.0043
0.0000078
0.00003
0.0018
0.000015
0.000049
0.000011
0.000026
5.5E-09
0.000022
0.012
NR
0.00016
0.000058
0.0000059
0.000002
0.009
0.00002
0.002
0.00003
0.03
0.002
0.00002
0.04
NR
0.8
2.4
0.0098
0.09
0.0001
0.00005
0.000065
NR
0.27
0.6
2.36
0.24
0.01
0.10
2.47
0.23
1.54
0.21
0.01
0.25
0.03
2.18
O.01
0.01
12.02
1.29
0.05
0.23
0.30
5.18
NR
0.31
0.42
19.27
6.86
2.77
3.17
0.01
2.77
0.91
0.01
0.03
2.34
NR
0.21
3.15
1.37
0.61
0.26
11.89
0.01
O.01
0.08
0.11
0.08
0.01
NR
0.01
O.01
0.22
O.01
0.01
0.24
0.02
NR
O.01
0.01
2.95 ±0.58
0.58 ±0.150
0.07 ±0.01
O.01±O.01
0.91 ±0.16
0.10 ±0.03
0.01 ±0.01
0.63 ±0.05
0.01 ±0.01
0.23 ±0.08
0.03 ±O.01
3. 19 ±0.66
0.09 ±0.02
0.01 ±0.01
0.02 ±0.01
<0.01±<0.01
0.05 ±0.01
0.17 ±0.03
0.10 ±0.04
6.49
NR
4.48
4.53
7.09
2.88
1.18
9.38
0.68
2.48
0.81
0.02
1.92
0.49
NR
0.19
2.66
1.03
0.20
0.33
28.83
0.03
0.04
0.03
0.05
0.03
0.02
NR
0.01
O.01
0.33
O.01
0.01
0.33
0.02
NR
O.01
0.01
to
o
* Metals sampled were sampled with PMi0 filters
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
-------
• Carbon tetrachloride had the highest theoretical cancer risk for S4MO (9.38 in-a-
million).
• Acrolein was the only pollutant that exhibited a noncancer HQ greater than 1 (28.83),
based on the 2006 annual average at S4MO. All other noncancer HQs were less than
0.40.
• According to the 1999 NAT A, manganese had the highest modeled concentration
(12.02 |ig/m3).
• Benzene (19.27 in-a-million), 1,3-butadiene (6.86), and acetaldehyde (5.18) have the
highest NATA-modeled cancer risks for pollutants that failed screens at S4MO.
• Like the noncancer risks based on the 2006 annual average, the only NATA-modeled
noncancer risk greater than 1 was for acrolein (11.89).
17.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 17-8 and 17-9 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 17-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest cancer toxicity-weighted emissions, and the 10 pollutants
with the highest cancer risk (in-a-million) as calculated from the annual average. Table 17-9
presents similar information, but identifies the 10 pollutants with the highest noncancer risk
(HQ) as calculated from the annual average. The pollutants in these tables are limited to those
that have cancer and noncancer risk factors, respectively. As a result, the highest emitted
pollutants in the cancer table may not be the same as the noncancer tables, although the actual
value of the emissions will be. Secondly, each site sampled for specific types of pollutants.
Therefore, the cancer risks based on each site's annual average is limited to those pollutants for
which each respective site sampled. S4MO sampled for VOC, metals, hexavalent chromium,
and carbonyl compounds. In addition, the highest cancer and noncancer risk based on annual
averages are limited to those pollutants failing at least one screen.
17-21
-------
Table 17-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Site in Missouri
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for St. Louis)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for St. Louis)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for S4MO)
Pollutant
Noncancer
Risk
(HQ)
St. Louis, Missouri - S4MO
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Trichloroethylene
Tetrachloroethylene
Dichloromethane
Naphthalene
Poly cyclic Organic Matter as 15-PAH
Nickel
252.44
160.07
62.89
29.99
27.61
18.28
13.23
7.76
1.15
0.70
Benzene
1,3 -Butadiene
Arsenic
Hydrazine
Naphthalene
Acetaldehyde
Nickel
Tetrachloroethylene
Polycyclic Organic Matter as 7-PAH
Hexavalent Chromium
1.97E-03
9.00E-04
3.76E-04
3.19E-04
2.64E-04
1.38E-04
1.12E-04
1.08E-04
9.38E-05
9.34E-05
Carbon Tetrachloride
Benzene
Acetaldehyde
Arsenic
Acrylonitrile
1,3 -Butadiene
1 , 1 ,2,2-Tetrachloroethane
£>-Dichlorobenzene
Hexachloro- 1 ,3 -butadiene
Cadmium
9.38
7.09
6.49
4.53
4.48
2.88
2.66
2.48
1.92
1.18
to
to
-------
Table 17-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Site in Missouri
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for St. Louis)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for St. Louis)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for S4MO)
Pollutant
Noncancer
Risk
(HQ)
St. Louis, Missouri - S4MO
Toluene
Xylenes
Methanol
Hydrochloric Acid
Methyl Tert-Butyl Ether
Methyl Ethyl Ketone
Ethylene Glycol
Benzene
Formaldehyde
Methyl Isobutyl Ketone
688.46
453.77
445.40
348.67
307.77
278.82
254.91
252.44
160.07
142.97
Acrolein
Chlorine
Hydrochloric Acid
Formaldehyde
1,3 -Butadiene
Nickel
Maleic Anhydride
Benzene
Acetaldehyde
Manganese
386,409.41
23,771.26
17,433.37
16,333.56
14,995.08
10,815.37
9,645.64
8,414.77
6,987.50
5,315.48
Acrolein
Manganese
Acetaldehyde
Formaldehyde
1,3 -Butadiene
Arsenic
Acrylonitrile
Cadmium
Benzene
Nickel
28.83
0.33
0.33
0.33
0.05
0.04
0.03
0.03
0.03
0.02
to
-------
The following observations can be made from Table 17-8:
• Benzene was the highest emitted pollutant with a cancer risk factor, had the highest
cancer toxicity-weighted emissions, and had the second highest cancer risk based on
the 2006 annual average for S4MO.
• Carbon tetrachloride had the highest cancer risk based on the 2006 annual average,
yet this pollutant was neither one of the highest emitted nor one of the most toxic
based on the 2002 NEI emission inventory.
• Benzene, acetaldehyde, and 1,3-butadiene appeared on all three "top 10" lists.
The following observations can be made from Table 17-9:
• Although toluene and xylenes were the highest emitted pollutants with noncancer risk
factors in St. Louis City, they did not rank in the top 10 based on toxicity-weighted
emissions or the annual average-based noncancer risk.
• Acrolein had the highest noncancer toxicity-weighted emissions in St. Louis City and
had the highest noncancer risks based on the 2006 annual average at both sites, but
did not appear in the list of highest emitted pollutants.
• Formaldehyde, acetaldehyde, and manganese tied for second highest noncancer risk
based on the 2006 annual averages and had some of the highest toxicity-weighted
emissions, but only formaldehyde had one of the highest total emissions near S4MO.
Missouri Pollutant Summary
The pollutants of interest at the Missouri site were acetaldehyde, acrolein, arsenic,
benzene, 1,3-butadiene, cadmium, carbon tetrachloride, formaldehyde, manganese,
p-dichlorobenzene, and tetrachloroethylene.
Formaldehyde had the highest daily average for S4MO. Formaldehyde was highest in
summer, and acetaldehyde was highest in spring.
Acrolein was the only pollutant to exceed either of the short-term risk factors.
A comparison of formaldehyde, benzene, and 1,3-butadiene concentrations for all years
of UATMP participation shows that concentrations of all three pollutants appear to have
decreased from 2005 to 2006. However, the formaldehyde confidence intervals indicate
that this decrease in formaldehyde was not statistically significant.
17-24
-------
18.0 Sites in New Jersey
This section presents meteorological, concentration, and spatial trends for the four
UATMP sites in New Jersey (CANJ, CHNJ, ELNJ, and NBNJ). The four sites are located in
Camden, Chester, Elizabeth, and New Brunswick, New Jersey, respectively. Figures 18-1
through 18-4 are topographical maps showing the monitoring sites in their urban and rural
locations. Figures 18-5 through 18-7 identify point source emission locations within 10 miles of
the sites that reported to the 2002 NEI for point sources. CANJ is located on the southwest side
of the state, near the PA/NJ border and east of Philadelphia. A number of point sources are
located mainly to its north and west, most of which are involved in fuel combustion processes.
CHNJ is located in the north-central part of New Jersey and has only eight industrial sources
nearby, most of which lie just within the 10 mile radius from the site. ELNJ and NBNJ are close
to each other, with the outer portions of their 10 mile radii intersecting. These two sites are near
the New Jersey/New York border, just west of Staten Island, and have a number of sources in the
vicinity, most of which are fuel combustion processes, chemical and allied products production,
and liquid distribution processes.
Storm systems frequently track across New Jersey, producing fairly variable weather.
However, its proximity to the Atlantic Ocean has a moderating effect on temperature. Summers
along the coast tend to be cooler than areas farther inland, while winters tend to be warmer. New
Jersey's location also allows for ample annual precipitation and high humidity. A southwesterly
wind is most common in the summer and a northwesterly wind is typical in the winter (Ruffner
andBair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to CANJ is Philadelphia International (WBAN 13739); the closest station to CHNJ and NBNJ is
Somerville-Somerset Airport (WBAN 54785); and Newark International Airport (WBAN
14734)
18-1
-------
Figure 18-1. Camden, New Jersey (CANJ) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
18-2
-------
Figure 18-2. Chester, New Jersey (CHNJ) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
18-2
-------
Figure 18-3. Elizabeth, New Jersey (ELNJ) Monitoring Site
-.-••t
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
18-4
-------
Figure 18-4. New Brunswick, New Jersey (NBNJ) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
18-5
-------
Figure 18-5. Facilities Located Within 10 Miles of CANJ
Montgomery
fnunty
Philadelphia"
~~ Counly \
'•<
' T" ——.:
Burlington
County
F F
FPL
Carnden
County
SF*
f
; 4
Delaware
County
pc D
Gloucester
County
Noie; Due to fadlrty dvnsitv a»d collocdtiott the total facilities
displayed may nol represent all facililies within She area of interest
Legend
CANJ UATMP site
10 mile radius
County boundary
Source Category Group (No. of Facilities)
* Agricultural Chemicals Production Industrial Facility (1)
¥ Automotive Repair, Services, & Parking (1)
'. Business Services Facility (1 }
c Chemicals S Allied Products Facility (7)
Z Electrical & Electronic Equipment Facility (1)
D Fabricated Metal Products Facility (3)
F Fuel Combustion Industrial Facility (64)
I Incineration Industrial Facility (3)
' Instruments & Related Products Facility (1)
L Liquids Distribution Industrial Facility (11)
x Miscellaneous Manufacturing Industries (3)
P Miscellaneous Processes Industrial Facility (12)
: Motor Freight Transportation & Warehousing (1)
\ Non-ferrous Metals Processing Industrial Facility (4)
2 Nonmetallic Minerals, Except Fuels (1)
P Petroleum/Nat. Gas Prod. & Refining Industrial Facility (3)
v Polymers S Resins Production Industrial Facility (1)
Q Primary Metal Industries Facility (2)
# Production of Inorganic Chemicals Industrial Facility (1)
4 Production of Organic Chemicals Industrial Facility (6)
c: Pulp & Paper Production Facility (1 )
s Surface Coating Processes Industrial Facility (9)
s Utility Boilers (7)
T Waste Treatment & Disposal Industrial Facility (2)
r Wholesale Trade (1)
18-6
-------
Figure 18-6. Facilities Located Within 10 Miles of CHNJ
Warren
County
County
Morris
County
Somerset
County
Hunterdon
County
Note; Due to facility density and collocation, the sotai facilities
displayed may not represent aft facilities within the area of interest.
Legend
•&• CHNJ UATMP site
• . • 10 mile radius
County boundary
Source Category Group (No. of Facilities)
c Chemicals & Allied Products Facility (1)
F Fuel Combustion Industrial Facility (1)
J Industrial Machinery & Equipment Facility (1)
P Miscellaneous Processes Industrial Facility (1)
» National Security & International Affairs (1)
Q Primary Metal Industries Facility {1}
4 Production of Organic Chemicals Industrial Facility (1}
i Waste Treatment & Disposal Industrial Facility (1)
18-7
-------
Figure 18-7. Facilities Located Within 10 Miles of ELNJ and NBNJ
Legend
•&•• ELNJ UATMP site
Note: Due to fadlcty density and collocation, the total facilities
displayed may no! represent ali facilities within the area of interest.
-jjr NBNJ U ATM P site
10 mile radius
County boundary
Source Category Group (No. of Facilities)
* Agricultural Chemicals Production Industrial Facility (2)
: Business Services Facility (2}
c Chemicals & Aflied Products Facility (31 )
E Electric, Gas, & Sanitary Services (1 )
D Fabricated Metal Products Facility (10)
K Ferrous Metals Processing Industrial Facility (2)
F Fuel Combustion industrial Facility (45)
I Incineration Industrial Facility (3)
J Industrial Machinery & Equipment Facility (3)
= Instruments & Related Products Facility (1 )
i- Integrated Iron & Steel Manufacturing Facility (1 )
Leather & Leather Products Facility (2)
L Liquids Distribution Industrial Facility (22)
x Metal Mining (1)
B Mineral Products Processing Industrial Facility (6)
x Miscellaneous Manufacturing industries (1 )
Miscellaneous Processes Industrial Facility (29)
Non-ferrous Metals Processing Industrial Facility (1)
Petroleum/Nat, Gas Prod. 8 Refining Industrial Facility (3)
Pharmaceutical Production Processes Industrial Facility (8)
Polymers & Resins Production Industrial Facility (5)
Primary Metal Industries Facility (6)
Production of Organic Chemicals Industrial Facility (8)
Pulp S Paper Production Facility (2)
Rubber & Miscellaneous Plastic Products Facility (5)
Stone. Clay, Glass, & Concrete Products (1)
Surface Coating Processes Industrial Facility {15)
Transportation Equipment (1)
Transportation by Air (1)
Utility Boilers (6)
Waste Treatment & Disposal Industrial Facility (8)
Wholesale Trade (3)
18-8
-------
is the closest weather station to ELNJ. Table 18-1 presents average meteorological conditions of
temperature (average maximum and average), moisture (average dew point temperature, average
wet-bulb temperature, and average relative humidity), pressure (average sea level pressure), and
wind information (average scalar wind speed) for the entire year and on days samples were
collected. Also included in Table 18-1 is the 95 percent confidence interval for each parameter.
As shown in Table 18-1, average meteorological conditions on sampling days were fairly
representative of average weather conditions throughout the year.
18.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Michigan
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total screens. The New Jersey sites sampled for carbonyl
compounds and VOC only. Table 18-2 presents the pollutants that failed at least one screen at
the New Jersey monitoring sites.
The following observations are shown in Table 18-2:
• Fifteen pollutants with a total of 446 measured concentrations failed the screen at
CANJ; twelve pollutants with a total of 299 measured concentrations failed the screen
at CJrtNJ; seventeen pollutants with a total of 451 measured concentrations failed the
screen at ELNJ; and twelve pollutants with a total of 326 measured concentrations
failed the screen at NBNJ.
• The pollutants of interest also varied by site, yet the following seven pollutants
contributed to the top 95 percent of the total failed screens at each New Jersey
monitoring site: acetaldehyde, acrolein, benzene, 1,3-butadiene, formaldehyde,
carbon tetrachloride, and tetrachloroethylene.
• One hundred percent of the acrolein, carbon tetrachloride, and benzene measured
detections failed the screen at each New Jersey site.
18-9
-------
Table 18-1. Average Meteorological Conditions near the Monitoring Sites in New Jersey
Site
CANJ
CHNJ
ELNJ
NBNJ
WBAN
13739
54785
14734
54785
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
<°F)
65.58
±1.68
65.53
±4.06
64.83
± 1.69
64.70
±3.99
64.82
±1.71
64.68
±4.15
64.83
± 1.69
64.47
±4.03
Average
Temperature
(°F)
57.51
±1.59
57.50
±3.83
54.30
±1.59
54.06
±3.82
57.09
±1.62
57.16
±3.89
54.30
±1.59
53.91
±3.84
Average
Dew Point
Temperature
(°F)
42.76
±1.83
43.55
±4.26
42.45
±1.85
43.48
±4.25
41.83
±1.82
42.79
±4.12
42.45
±1.85
43.22
±4.30
Average
Wet Bulb
Temperature
(°F)
50.46
±1.49
50.73
±3.53
48.74
±1.55
48.96
±3.66
48.82
±1.50
50.15
±3.49
48.74
±1.55
48.79
±3.70
Average
Relative
Humidity
(%)
61.17
±1.56
63.21
±4.08
67.90
±1.43
71.20
±3.41
59.75
±1.50
61.81
±3.73
67.90
±1.43
70.91
±3.45
Average
Sea Level
Pressure
(mb)
1016.11
±0.73
1016.07
± 1.70
1015.30
±0.74
1015.16
±1.69
1015.51
±0.74
1015.55
± 1.73
1015.30
±0.74
1015.27
±1.71
Average
Scalar Wind
Speed
(kt)
8.18
±0.34
7.53
±0.72
3.65
±0.26
3.30
±0.60
8.71
±0.33
8.13
±0.78
3.65
±0.26
3.33
±0.60
oo
I
o
18-10
-------
Table 18-2. Comparison of Measured Concentrations and EPA Screening Values
for the New Jersey Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Camden, New Jersey - CANJ
Formaldehyde
Acetaldehyde
Benzene
Carbon Tetrachloride
1,3 -Butadiene
£>-Dichlorobenzene
Tetrachloroethylene
Acrolein
Bromomethane
Trichloroethylene
Acrylonitrile
Dichloromethane
Methyl tert-Butyl Ether
1 ,2-Dichloroethane
Hexachloro- 1 ,3 -butadiene
Total
57
57
53
53
51
49
49
42
14
9
4
3
3
1
1
446
57
57
53
53
52
51
52
42
53
42
4
53
49
1
1
620
100.00
100.00
100.00
100.00
98.08
96.08
94.23
100.00
26.42
21.43
100.00
5.66
6.12
100.00
100.00
71.94
12.78
12.78
11.88
11.88
11.43
10.99
10.99
9.42
3.14
2.02
0.90
0.67
0.67
0.22
0.22
12.78
25.56
37.44
49.33
60.76
71.75
82.74
92.15
95.29
97.31
98.21
98.88
99.55
99.78
100.00
Chester, New Jersey - CHNJ
Benzene
Carbon Tetrachloride
Acetaldehyde
Formaldehyde
Acrolein
1,3 -Butadiene
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
1,2-Dichloroethane
£>-Dichlorobenzene
Chloromethylbenzene
Acrylonitrile
Total
58
58
57
49
41
14
12
4
2
2
1
1
299
58
58
58
58
41
37
45
4
2
22
1
1
385
100.00
100.00
98.28
84.48
100.00
37.84
26.67
100.00
100.00
9.09
100.00
100.00
19.40
19.40
19.06
16.39
13.71
4.68
4.01
1.34
0.67
0.67
0.33
0.33
19.40
38.80
57.86
74.25
87.96
92.64
96.66
97.99
98.66
99.33
99.67
100.00
77.66
Elizabeth, New Jersey - ELNJ
Formaldehyde
Acetaldehyde
Carbon Tetrachloride
Benzene
1,3 -Butadiene
Acrolein
Tetrachloroethylene
£>-Dichlorobenzene
Methyl tert-Butyl Ether
59
59
58
58
55
50
44
40
6
59
59
58
58
55
50
56
55
48
100.00
100.00
100.00
100.00
100.00
100.00
78.57
72.73
12.50
13.08
13.08
12.86
12.86
12.20
11.09
9.76
8.87
1.33
13.08
26.16
39.02
51.88
64.08
75.17
84.92
93.79
95.12
18-11
-------
Table 18-2. Comparison of Measured Concentrations and EPA Screening Values
for the New Jersey Monitoring Sites (Continued)
Pollutant
Hexachloro- 1 , 3 -butadiene
Xylenes
Acrylonitrile
1 ,2-Dichloroethane
Dichloromethane
1 , 1 ,2,2-Tetrachloroethane
1 , 1 ,2-Trichloroethane
Trichloroethylene
Total
#of
Failures
5
4
4
3
2
2
1
1
451
#of
Measured
Detections
5
58
4
3
58
2
1
33
662
% of Screens
Failed
100.00
6.90
100.00
100.00
3.45
100.00
100.00
3.03
68.13
% of Total
Failures
1.11
0.89
0.89
0.67
0.44
0.44
0.22
0.22
Cumulative
%
Contribution
96.23
97.12
98.00
98.67
99.11
99.56
99.78
100.00
New Brunswick, New Jersey - NBNJ
Acetaldehyde
Carbon Tetrachloride
Benzene
Formaldehyde
Acrolein
1,3 -Butadiene
Tetrachloroethylene
£>-Dichlorobenzene
Acrylonitrile
Hexachloro- 1 ,3 -butadiene
1,2-Dichloroethane
1, 1,2,2-Tetrachloroethane
Total
53
51
51
47
33
30
28
17
7
5
3
1
326
53
51
51
52
o o
JJ
42
47
44
7
5
o
6
i
389
100.00
100.00
100.00
90.38
100.00
71.43
59.57
38.64
100.00
100.00
100.00
100.00
83.80
16.26
15.64
15.64
14.42
10.12
9.20
8.59
5.21
2.15
1.53
0.92
0.31
16.26
31.90
47.55
61.96
72.09
81.29
89.88
95.09
97.24
98.77
99.69
100.00
18.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
18-12
-------
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. The daily and seasonal average concentrations
are presented in Table 18-3. Annual averages are presented and discussed in further detail in
later sections.
The following observations for CANJ are shown in Table 18-3:
Among the daily averages for CANJ, formaldehyde had the highest concentration by
7M
(1.16 ±0.13 |ig/m3).
mass (3.54 ± 0.47 |ig/m3), followed by acetaldehyde (2.04 ± 0.23 |ig/m3) and benzene
• Most of the seasonal averages of the pollutants of interest for CANJ did not vary
much statistically from season-to-season.
• Carbon tetrachloride was higher in summer and autumn (0.72 ± 0.09 |ig/m3 and 0.71
± 0.08 |ig/m3, respectively) than winter and spring (0.48 ± 0.07 |ig/m3 and 0.49 ± 0.09
|ig/m3, respectively).
• The summer formaldehyde average (5.05 ± 1.09 |ig/m3) was the highest seasonal
formaldehyde average.
The following observations for CHNJ are shown in Table 18-3:
• The pollutants with the highest daily averages for CFtNJ were formaldehyde (1.93 ±
0.28 |ig/m3) and acetaldehyde (1.19 ± 0.15 |ig/m3).
• Some of the CFENJ pollutants of interest do not have seasonal averages listed in Table
18-3 because there were so few measured detections. For the pollutants with valid
seasonal averages, most of them did not vary much among the seasons.
• Formaldehyde was the one exception. The summer formaldehyde average (3.15 ±
0.66 |ig/m3) was higher than the winter, spring, and fall averages (1.43 ± 0.28 |ig/m3,
1.77 ± 0.42 |ig/m3, and 1.57 ± 0.39 |ig/m3, respectively).
The following observations for ELNJ are shown in Table 18-3:
• The pollutants with the highest daily averages for ELNJ were acetaldehyde (5.67 ±
0.74 |ig/m3), formaldehyde (4.51 ± 0.59 |ig/m3), and methyl tert-buty\ ether (1.74 ±
0.90 |ig/m3).
• The acetaldehyde average for ELNJ was significantly higher than the acetaldehyde
averages for the other New Jersey sites.
18-13
-------
Table 18-3. Daily and Seasonal Averages for the Pollutants of Interest for the New Jersey Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Ug/m3)
Conf.
Int.
Spring
Avg
(Ug/m3)
Conf.
Int.
Summer
Avg
(Ug/m3)
Conf.
Int.
Autumn
Avg
(Ug/m3)
Conf.
Int.
Camden, New Jersey - CANJ
Acetaldehyde
Acrolein
Benzene
Bromomethane
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Tetrachloroethylene
57
42
53
53
52
53
51
57
52
57
53
53
53
53
53
53
57
53
2.04
0.76
1.16
0.43
0.13
0.61
0.22
3.54
0.32
0.23
0.15
0.13
0.16
0.03
0.05
0.03
0.47
0.05
1.62
0.48
1.39
0.39
0.19
0.48
0.18
2.64
0.44
0.28
0.30
0.35
0.24
0.07
0.07
0.05
0.43
0.14
2.16
NR
1.03
0.70
0.09
0.49
0.15
3.98
0.23
0.51
NR
0.19
0.53
0.03
0.09
0.04
0.91
0.06
2.47
0.69
1.00
0.51
0.06
0.72
0.24
5.05
0.25
0.46
0.17
0.17
0.32
0.01
0.09
0.05
1.09
0.06
1.90
0.73
1.18
0.20
0.15
0.71
0.25
2.56
0.32
0.43
0.20
0.23
0.10
0.05
0.08
0.06
0.54
0.05
Chester, New Jersey - CHNJ
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Formaldehyde
Tetrachloroethylene
58
41
58
37
58
58
45
58
58
58
58
58
58
58
1.19
0.72
0.50
0.04
0.58
1.93
0.16
0.15
0.16
0.06
0.01
0.05
0.28
0.04
1.20
0.23
0.67
0.05
0.50
1.43
0.18
0.29
0.08
0.11
0.02
0.06
0.28
0.06
1.32
0.57
0.43
NR
0.49
1.77
NR
0.24
0.38
0.06
NR
0.08
0.42
NR
1.26
0.60
0.34
0.02
0.69
3.15
0.09
0.33
0.23
0.06
0.01
0.09
0.66
0.02
1.01
0.79
0.52
0.03
0.67
1.57
0.12
0.30
0.23
0.11
0.01
0.10
0.39
0.03
Elizabeth, New Jersey - ELNJ
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Methyl tert-Butyl Ether
Tetrachloroethylene
59
50
58
55
58
55
59
48
56
59
58
58
58
58
58
59
58
58
5.67
0.68
1.29
0.17
0.60
0.16
4.51
1.74
0.37
0.74
0.18
0.23
0.04
0.05
0.03
0.59
0.90
0.10
4.65
0.43
1.80
0.26
0.47
0.16
4.04
2.72
0.55
1.22
0.19
0.67
0.09
0.08
0.07
1.11
1.83
0.32
4.51
0.46
1.15
0.13
0.53
0.13
5.14
2.24
0.29
1.20
0.18
0.21
0.05
0.08
0.04
1.26
1.87
0.07
7.00
0.88
0.91
0.09
0.70
0.20
5.93
0.29
0.21
1.23
0.56
0.15
0.02
0.11
0.08
0.94
0.23
0.05
6.74
0.69
1.26
0.14
0.72
0.13
2.96
0.16
0.36
1.76
0.20
0.32
0.03
0.06
0.03
0.66
0.05
0.09
oo
-------
Table 18-3. Daily and Seasonal Averages for the Pollutants of Interest for the New Jersey Monitoring Sites (Continued)
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Hg/m3)
Conf.
Int.
Autumn
Avg
(Hg/m3)
Conf.
Int.
New Brunswick, New Jersey - NBNJ
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Tetrachloroethylene
53
33
51
42
51
44
52
47
53
51
51
51
51
51
53
51
3.35
0.60
0.67
0.07
0.61
0.09
2.63
0.28
0.49
0.18
0.09
0.02
0.06
0.01
0.77
0.11
2.89
0.37
0.88
0.10
0.51
0.08
2.07
0.28
0.84
0.25
0.23
0.04
0.08
0.03
0.51
0.10
3.72
NR
0.63
0.03
0.50
0.08
2.50
0.33
0.81
NR
0.08
0.01
0.09
0.03
0.41
0.32
4.52
0.61
0.51
0.03
0.78
0.08
2.51
0.18
0.87
0.22
0.08
0.01
0.11
0.02
0.58
0.04
1.85
0.42
0.56
NR
0.75
NR
3.72
0.20
0.68
0.09
0.14
NR
0.13
NR
4.18
0.09
NA = Not available due to short sampling duration.
NR = Not reportable due to the low number of measured detections.
oo
-------
• With the exception of carbon tetrachloride, the pollutants of interest were highest in
the summer or winter. However, the seasonal averages for ELNJ did not vary much
statistically.
• The one exception was methyl tert-butyl ether. This pollutant's winter and spring
averages (2.72 ± 1.83 |ig/m3 and 2.24 ± 1.87 |ig/m3, respectively) were much higher
than the other seasons. However, the confidence intervals indicate that these
averages were probably influenced by outliers.
The following observations for ELNJ are shown in Table 18-3:
• The pollutants with the highest daily averages for NBNJ were acetaldehyde (3.35 ±
0.49 |ig/m3), and formaldehyde (2.63 ± 0.77 |ig/m3).
• The summer and autumn carbon tetrachloride average concentrations were higher
than the other seasonal averages.
• 1,3-Butadiene was highest in winter.
• The very high confidence interval for formaldehyde's autumn average indicates the
likely presence of outliers.
18.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for New Jersey monitoring sites was
evaluated using ATSDR short-term (acute) and intermediate MRL and California EPA acute
REL factors. Acute risk is defined as exposures from 1 to 14 days while intermediate risk is
defined as exposures from 15 to 364 days. It is useful to compare the preprocessed daily
measurements to the short-term MRL and REL factors, as well as compare seasonal averages to
the intermediate MRL. Of the pollutants with at least one failed screen, only acrolein exceeded
either the acute and intermediate risk values, and each site's non-chronic risk is summarized in
Table 18-4.
The following observations about acrolein are shown in Table 18-4:
• All of the acrolein measured detections at the New Jersey sites were greater than the
ATSDR acute MRL value of 0.11 |ig/m3 and all but four of the acrolein measured
detections exceeded the California REL value of 0.19 |ig/m3.
18-16
-------
Table 18-4. Non-Chronic Risk Summary for the New Jersey Monitoring Sites
Site
CANJ
CHNJ
ELNJ
NBNJ
Method
TO- 15
TO- 15
TO- 15
TO- 15
Pollutant
Acrolein
Acrolein
Acrolein
Acrolein
Daily
Average
(ug/m3)
0.76
±0.15
0.72
±0.16
0.68
±0.18
0.60
±0.18
ATSDR
Short-term
MRL
(ug/m3)
0.11
0.11
0.11
0.11
# of ATSDR
MRL
Exceedances
42
41
50
33
CAL
EPA
REL
Acute
(Ug/m3)
0.19
0.19
0.19
0.19
# of CAL
EPA REL
Exceedances
42
39
50
31
ATSDR
Intermediate-
term MRL
(ug/m3)
0.09
0.09
0.09
0.09
Winter
Average
(Ug/m3)
0.48
±0.30
0.23
±0.08
0.43
±0.19
0.37
±0.25
Spring
Averag
e
(ug/m3)
NR
0.57
±0.38
0.46
±0.18
NR
Summer
Average
(Ug/m3)
0.69
±0.17
0.60
±0.23
0.88
±0.56
0.61
±0.22
Autumn
Average
(ug/m3)
0.73
±0.20
0.79
±0.23
0.69
±0.20
0.42
±0.09
NA = Not available due to short sampling duration.
NR = No reportable due to the low number of measured detections.
oo
-------
• The average detected concentration varied only slightly from 0.60 ±0.18 |ig/m3 (for
NBNJ) to 0.76 ±0.15 |ig/m3 (for CANJ), which were all significantly higher than
either acute risk factor.
• All seasonal averages for acrolein exceeded the ATSDR intermediate risk value
(0.09 |ig/m3).
For the pollutants that exceeded the short-term (acute) risk factors, the concentrations
were further examined by developing pollution roses for these pollutants. A pollution rose is a
plot of concentration and wind direction. For all four New Jersey monitoring sites, only acrolein
concentrations exceeded the acute risk factors. Figures 18-8 through 18-11 are pollution roses
for acrolein at the New Jersey sites.
Observations gleaned from the acrolein pollution roses include:
• Only 4 of the 166 acrolein concentrations did not exceed the acute risk factors, which
are indicated by a dashed line (CalEPA REL) and solid line (ATSDR MRL).
• Figure 18-8 shows that concentrations exceeding the acute risk factors occurred with
winds originating from a variety of directions at CANJ, which is a pattern consistent
with mobile sources. However, they were most frequently measured on days with
westerly winds. CANJ is located between several major thoroughfares, including I-
676. Although located in a predominantly residential area, many industrial sources
are located fairly close to the monitoring site.
• Figure 18-9 shows that concentrations exceeding the acute risk factors occurred with
winds originating from a variety of directions at CFINJ, a pattern consistent with
mobile sources. Only two concentrations were less than the CalEPA REL risk factor.
The highest concentration of acrolein occurred with an easterly wind. Although
located in a rural area, the CFINJ monitoring site is located near a main road through
town.
• Figure 18-10 shows that acrolein concentrations exceeding the acute risk factors
occurred with winds originating from a variety of directions at ELNJ. The highest
concentration of acrolein occurred with a west-southwesterly wind. ELNJ is located
near exit 13 of 1-95, which is also where 1-278 to Staten Island intersects 1-95. The
area is also very industrial with a major refinery located just south of the site.
• Figure 18-11 shows that concentrations exceeding the acute risk factors occurred with
winds originating from a variety of directions at NBNJ. Two concentrations were
less than the CalEPA REL risk factor. The highest concentrations of acrolein
18-18
-------
Figure 18-8. Acrolein Pollution Rose for CANJ
oo
VO
3.0
2.5
2.0
1.5
1.0
o.5
O 0.0
o
I
•3 0.5
1.0
1.5
2.0
2.5
NW
w
3.0
sw
*
*
3
CA EPA REL (0.19 |jg/m3
ATSDRMRL(0.11
•
*»
^r
Daily Avq Cone =0.76 ±0.15 uq/m3
3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5
Pollutant Concentration
1.0
1.5
2.0
2.5
NE
SE
3.0
-------
Figure 18-9. Acrolein Pollution Rose for CHNJ
oo
to
o
t.U
3.5
3.0
2.5
2.0
1.5
1 1'°
: Concentrat
o o
O Ul
Pollutant
-* o
O Ul
1.5
2.0
2.5
3.0
3.5
A n
NW N
-
-
-
•
, NE
— CA EPA REL (0.19 |jg/m3)
— ATSDRMRL(0.11 |jg/m3)
* *»**%* *
w * rffi: * E
ja?-**'*
* * r*"
-
-
-
-
sw s
, * :
* »
Daily Avq Cone =0.72 ±0.16 uq/m3 SE
4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Pollutant Concentration
-------
Figure 18-10. Acrolein Pollution Rose for ELNJ
oo
to
4.5
4.0
3.5
3.0
2.5
2.0
1.5
c
° 1.0
2
c 0.5
v
u
O 0.0
O
I 0.5
^3
O 1.0
Q.
1.5
2.0
2.5
3.0
3.5
4.0
4.5
sw
*» •
•CAEPAREL(0.19|jg/m3
-ATSDRMRL(0.11
NE
Daily Ava Cone =0.68 ±0.18 ua/m
SE
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
Pollutant Concentration
-------
Figure 18-11. Acrolein Pollution Rose for NBNJ
oo
to
to
4 0
NW N
3.5 — CA EPA REL (0. 1 9 pg/m3)
— ATSDRMRL (0.11 pg/m3)
3.0 I
2.5
2.0
A ;
1 *
1 °'5 U / Vi
ri n n ' * ' r
s 1 •£
|0.5 * *
1 1.0 *
I *
''I *
2.5
3.0
3.5
SW S
4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0
NE
* ^
"^ • E
f>%%
Daily Avq Cone =0.60 ±0.18 uq/m3 SE
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4
Pollutant Concentration
-------
occurred with southwesterly winds. Although the NBNJ monitoring site is located in
a rural area, it is also wedged between several major roadways. The site is positioned
just off a US-1 exit and is just west of the New Jersey Turnpike (1-95).
18.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
18.4.1 Pearson Correlation Analysis
Table 18-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the New Jersey monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for CANJ from Table 18-5:
• Strong positive correlations were calculated for formaldehyde, acetaldehyde, and
carbon tetrachloride and maximum and average temperatures. This indicates that
concentrations of these pollutants increase as temperature increases.
• Carbon tetrachloride and formaldehyde also exhibited strong positive correlations
with one or more moisture variables, indicating that moisture content also plays a role
in the concentrations of these pollutants.
The following observations are gathered for CJrDSTJ from Table 18-5:
• Carbon tetrachloride and formaldehyde also exhibited moderately strong positive
correlations with the temperature and moisture variables at this site. This indicates
that concentrations of these pollutants increase as temperature and moisture content
increase.
• Benzene exhibited strong negative correlations with the temperature and moisture
variables. This indicates that concentrations of benzene decrease as temperature and
moisture content increase.
• Strong negative correlations were also calculated between 1,3-butadiene and relative
humidity.
The following observations are gathered for ELNJ from Table 18-5:
18-23
-------
Table 18-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
New Jersey Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar Wind
Speed
Camden, New Jersey - CANJ
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Bromomethane
Carbon Tetrachloride
Formaldehyde
£>-Dichlorobenzene
Tetrachloroethylene
52
57
42
53
53
53
57
51
52
-0.29
0.58
0.15
-0.05
0.13
0.53
0.68
0.36
-0.29
-0.35
0.51
0.15
-0.11
0.08
0.54
0.63
0.33
-0.30
-0.29
0.40
0.12
-0.03
-0.03
0.56
0.45
0.31
-0.13
-0.34
0.45
0.14
-0.08
0.01
0.56
0.54
0.32
-0.24
0.06
-0.09
-0.03
0.15
-0.18
0.19
-0.19
0.06
0.33
0.18
0.16
-0.18
0.10
0.10
-0.14
0.03
0.10
0.12
-0.35
-0.43
0.27
-0.37
-0.24
0.12
-0.26
-0.32
-0.36
Chester, New Jersey - CHNJ
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Carbon Tetrachloride
Formaldehyde
Tetrachloroethylene
37
58
41
58
58
58
45
-0.40
0.13
0.08
-0.51
0.48
0.68
-0.31
-0.42
0.03
0.07
-0.55
0.52
0.60
-0.37
-0.50
0.01
0.02
-0.42
0.54
0.54
-0.34
-0.45
0.01
0.05
-0.50
0.54
0.57
-0.36
-0.43
-0.02
-0.11
0.13
0.28
0.05
-0.04
-0.01
0.24
0.15
0.03
-0.17
-0.01
0.05
0.40
-0.37
-0.06
-0.08
0.06
-0.39
-0.04
oo
to
-------
Table 18-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
New Jersey Monitoring Sites (Continued)
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar Wind
Speed
Elizabeth, New Jersey - ELNJ
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Carbon Tetrachloride
Formaldehyde
Methyl fer/-Butyl Ether
£>-Dichlorobenzene
Tetrachloroethylene
55
59
50
58
58
59
48
55
56
-0.29
0.53
0.28
-0.17
0.41
0.52
-0.07
0.21
-0.20
-0.32
0.47
0.31
-0.21
0.44
0.45
-0.12
0.18
-0.23
-0.21
0.37
0.33
-0.11
0.51
0.29
-0.10
0.15
-0.11
-0.28
0.42
0.33
-0.17
0.50
0.36
-0.13
0.15
-0.18
0.22
-0.11
0.13
0.20
0.28
-0.25
0.02
-0.01
0.25
0.11
0.17
-0.12
0.16
-0.13
0.11
0.15
-0.08
0.08
-0.51
-0.48
0.12
-0.56
-0.07
-0.37
-0.48
-0.32
-0.41
New Brunswick, New Jersey - NBNJ
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Carbon Tetrachloride
Formaldehyde
£>-Dichlorobenzene
Tetrachloroethylene
42
53
33
51
51
52
44
47
-0.42
0.40
0.46
-0.28
0.54
0.18
0.15
0.00
-0.49
0.30
0.46
-0.38
0.55
0.10
0.03
-0.06
-0.39
0.22
0.43
-0.25
0.58
0.09
0.06
-0.10
-0.45
0.25
0.45
-0.33
0.58
0.09
0.03
-0.09
0.21
-0.04
0.02
0.27
0.32
0.02
0.13
-0.12
0.00
0.06
-0.11
0.01
-0.15
0.23
0.04
-0.15
-0.18
-0.34
0.20
-0.36
-0.14
-0.32
-0.24
-0.04
oo
to
-------
• Correlations calculated between acetaldehyde and formaldehyde and maximum
temperature were strong and positive, indicating that concentrations of these
pollutants increase as temperature increases
• Carbon tetrachloride exhibited strong positive correlations with the moisture
variables, indicating the increased moisture content correlates to increased
concentrations of carbon tetrachloride.
• Benzene and 1,3-butadiene exhibited strong negative correlations with the scalar
wind speed. This indicates that as wind speed decreases, the concentrations of these
pollutants increase.
The following observations are gathered for NBNJ from Table 18-5:
• Strong positive correlations were calculated between carbon tetrachloride and the
maximum, average, dew point, and wet bulb temperatures. This indicates that
concentrations of this pollutant increases as temperature and moisture content
increase.
• The remaining correlations were weak.
18.4.2 Composite Back Trajectory Analysis
Figures 18-12 through 18-15 are composite back trajectory maps for the New Jersey
monitoring sites for the days on which sampling occurred. Each line represents the 24-hour
trajectory along which a parcel of air traveled toward the monitoring site on a sampling day.
Each concentric circle around the site in Figure 18-12 through Figure 18-15 represents 100
miles.
The following observations can be made from Figures 18-12 through 18-15:
• Back trajectories originated from a variety of directions at the New Jersey sites.
• The back trajectories originated less frequently from the east at these sites.
• The 24-hour airshed domains were somewhat large, with trajectories originating as
far away as western Quebec, Canada (> 600 miles).
• Most of the trajectories originated within 400 miles of the monitoring sites.
18-26
-------
Figure 18-12. Composite Back Trajectory Map for CANJ
oo
to
-------
Figure 18-13. Composite Back Trajectory Map for CHNJ
oo
to
oo
-------
Figure 18-14. Composite Back Trajectory Map for ELNJ
oo
to
VO
-------
Figure 18-15. Composite Back Trajectory Map for NBNJ
oo
I
OJ
o
V \ \
\ \
\ \
\ \ \
\ i \ \
0 75 150
-------
18.4.3 Wind Rose Analysis
Hourly wind data from the weather stations closest to the sites were uploaded into a wind
rose software program, WRPLOT (Lakes, 2006). WRPLOT produces a graphical wind rose
from the wind data. A wind rose shows the frequency of wind directions about a 16-point
compass, and uses different shading to represent wind speeds. Figures 18-16 through 18-19 are
the wind roses for the New Jersey monitoring sites on days sampling occurred.
Observations from Figure 18-16 for CANJ include:
• Hourly winds originated from a variety of directions on days samples were collected
near CANJ.
• However, an apparent lack of winds originating from the northeast and southeast is
evident in Figure 18-16.
• Wind observations were recorded most frequently from southwest and west-
northwest (9 percent each of observations).
• In regards to wind speed, most of observations (40 percent) ranged from 7 to 11
knots.
• Calm winds (<2 knots) were recorded for 10 percent of the hourly observations.
Observations from Figure 18-17 for CHNJ include:
• Fifty-five percent of wind observations were calm (<2 knots) near CHNJ, for which
there is no associated direction.
• For winds speeds greater than 2 knots, hourly winds originated primarily from the
north (9 percent of observations) and south (6 percent) on days samples were
collected near CHNJ.
Observations from Figure 18-18 for ELNJ include:
• Hourly winds originated primarily from the west (10 percent of observations) and
west-southwest (10 percent) near ELNJ.
• Similar to CANJ, an apparent lack of winds originating from the east and southeast is
evident in Figure 18-18.
18-31
-------
Figure 18-16. Wind Rose for CANJ Sampling Days
i o%
oo
I
OJ
to
SOUTH ----
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
^| 11 - 17
• 2- 4
Calms: 9.51%
-------
Figure 18-17. Wind Rose for CHNJ Sampling Days
•NORTH"---.
WEST
OO
-------
Figure 18-18. Wind Rose for ELNJ Sampling Days
oo
-------
Figure 18-19. Wind Rose for NBNJ Sampling Days
MORTH"---.
WEST
OO
-------
• In regards to wind speed, most of observations (40 percent) ranged from 7 to 11
knots. Calm winds (<2 knots) were recorded for 6 percent of the hourly observations.
Observations from Figure 18-19 for NBNJ include:
• The wind rose for NBNJ is similar to CHNJ's wind rose. This is reasonable as the
weather stations for the CHNJ and NBNJ are both from the Somerville-Somerset
Airport.
• Fifty-five percent of wind observations were also calm (<2 knots).
• Hourly winds near NBNJ originated primarily from the north (9 percent of
observations) on days samples were collected.
18.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as this site did not sample for SNMOC.
18.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County level vehicle registration information was not available for Camden, Middlesex,
Morris, and Union Counties. Thus, state-level vehicle registration, from the Energy Information
Administration (EIA), was allocated to the county level using the county-level population
proportion. County-level population information in these counties was obtained from the U.S.
Census Bureau, and is summarized in Table 18-6. Table 18-6 also includes a vehicle registration
to county population ratio (vehicles per person). In addition, the population within 10 miles of
each site is presented. An estimation of 10-mile vehicle registration was computed using the
10-mile population surrounding the monitor and the vehicle registration ratio. Finally,
Table 18-6 contains the average daily traffic information, which represents the average number
of vehicles passing the monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 18-6 include:
• County population is highest in Middlesex County, where NBNJ is located.
• The estimated number of vehicles registered near each site is similar.
18-36
-------
Table 18-6. Motor Vehicle Information for the New Jersey Monitoring Sites
Site
CANJ
CHNJ
ELNJ
NBNJ
2006 Estimated
County Population
517,001
493,160
531,088
786,971
Number of
Vehicles Registered
371,045
353,934
381,155
353,934
Vehicles per Person
(Registration: Population)
0.72
0.72
0.72
0.72
Population
Within
10 Miles
2,017,289
241,918
2,187,129
796,347
Estimated
10 Mile Vehicle
Ownership
1,447,782
173,621
1,569,674
571,528
Traffic Data
(Daily
Average)
62,000
12,623
170,000
63,000
oo
-------
• Not surprisingly, the 10-mile population is lowest near CHNJ, the most rural site, and
highest near ELNJ, the site closest to Newark and New York City. Ten mile
population and estimated vehicle registration is second highest near CANJ, which is
located near Philadelphia.
• The CHNJ and ELNJ sites also have the least and most daily traffic volume passing
the sites, respectively.
• In relation to the other UATMP sites, the county-level populations are mid-range;
however, ELNJ and CANJ have the highest and third highest 10-mile radius
populations, and highest two estimated 10-mile vehicle registrations.
• The ELNJ site's daily traffic count is second only to one of the Chicago sites (SPIL)
18.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compares them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• Of the four New Jersey sites, the ELNJ monitoring site's ratios most resembled those
of the roadside study, although the benzene-ethylbenzene and xylenes-ethylbenzene
ratios were closer together at this site than they were for the roadside study. This
suggests that mobile source emissions are major influences at this site.
• For NBNJ, the benzene-ethylbenzene and xylenes-ethylbenzene ratios were also very
similar (3.94 ± 0.45 and 3.79 ± 0.20, respectively), but the benzene-ethylbenzene
ratio was higher while the toluene-ethylbenzene ratio was relatively close to that of
the roadside study (5.70 ± 0.34 vs. 5.85).
• For CANJ and CFINJ, the benzene-ethylbenzene ratio was higher than the xylenes-
ethylbenzene ratio (4.67 ± 0.38 and 3.60 ± 0.22, and 5.60 ± 0.50 and 3.04 ± 0.20,
respectively), which is the opposite of the roadside study. The CANJ toluene-
ethylbenzene ratio was somewhat higher than that of the roadside study (7.41 ± 0.66
vs. 5.85), while that of CFINJ (5.71 ± 0.42) was very close to that of the roadside
18-38
-------
study. The benzene-ethylbenzene and toluene-ethylbenzene ratios for CHNJ were
very similar.
18.6 Trends Analysis
For sites that participated in the UATMP prior to 2005 and are still participating in the
2006 program year (i.e., minimum 3 consecutive years); a site-specific trends analysis was
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. CANJ
has participated in the UATMP since 1994; ELNJ since 1999; and CHNJ and NBNJ since 2001.
Figures 18-20 through 18-23 are trends figures for formaldehyde, benzene, and 1,3-butaidene
for CANJ, CHNJ, ELNJ, and NBNJ, respectively.
The following observations can be made from Figures 18-20 through 18-23:
• Figure 18-20 shows that there has been a lot of variation over the last 10 years. The
addition of confidence intervals shows that while the average concentrations have
changed over the years, the difference has generally not be statistically significant.
High formaldehyde concentrations in 1996, 1997, and 2004 may have been
influenced by outliers, as indicated by the large confidence intervals. However, the
overall trend, though slight, has been a decrease in all pollutants shown over the last
three years.
• Figure 18-21 shows that formaldehyde concentrations at CHNJ have been decreasing
since 2001. The slight increase in 2004 may have been influenced by outliers, as
indicated by the large confidence interval. Concentrations of 1,3-butadiene have not
changed significantly since 2001. Benzene decreased from 2003 to 2006.
• As indicated in Figure 18-22, after two years of decreasing, formaldehyde
concentrations began to increase somewhat in the years 2003 to 2005 at the ELNJ
monitoring site. The 2006 formaldehyde concentration decreased slightly, but this
decrease was not statistically significant. Benzene and 1,3-butadiene concentrations
have decreased slightly since the onset of sampling.
• As indicated in Figure 18-23, formaldehyde levels at NBNJ decreased after 2001, but
increased in later years. The 2004 increase may have been influenced by outliers, as
indicated by the large confidence interval. The 2006 formaldehyde concentration was
a significant decrease from 2005. Benzene also decreased in 2006. 1,3-Butadiene
concentrations have not changed significantly since 2001.
18-39
-------
Figure 18-20. Comparison of Yearly Averages for the CANJ Monitoring Site
oo
-U
o
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Year
D1,3-Butadiene
1 Benzene
D Formaldehyde
-------
Figure 18-21. Comparison of Yearly Averages for the CHNJ Monitoring Site
oo
4.£
3.5
.a
a.
g
is
S 2.5
o
o
o
-------
Figure 18-22. Comparison of Yearly Averages for the ELNJ Monitoring Site
oo
-U
to
4.5
3.5
.a
a.
a.
o
+J
as
k.
1 2.5
o
o
o
O 9
O) z
1.5
2000
2001
2002
2003
Year
2004
2005
2006
D1,3-Butadiene
I Benzene
D Formaldehyde
-------
Figure 18-23. Comparison of Yearly Averages for the NBNJ Monitoring Site
oo
7 --
a.
S 5
c
g
+j
03
o
o
o
2
2001
2002
2003 2004
Year
2005
2006
D1,3-Butadiene
I Benzene
D Formaldehyde
-------
18.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the New Jersey sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 18-7.
Additionally, the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA were
retrieved and are also presented in Table 18-7. The NATA data are presented for the census tract
where the monitoring site is located.
The census tract information for the New Jersey sites is as follows:
• CANJ is located in census tract 34007601500 with a population of 6,424, which
represents 1.3 percent of the Camden County population in 2000.
• CHNJ is located in census tract 34027045901, with a population of 1,635, which
represents 0.3 percent of Morris County's 2000 population.
• ELNJ is located in census tract 34039030100. The population in that census tract in
2000 was 334, or less than 0.1 percent of Union County's population.
• NBNJ is located in census tract 34023006206. In 2000, the population in this census
tract was 1,794 or 0.2 percent of the Middlesex County population.
The following observations can be made about the concentrations from Table 18-7:
• Formaldehyde and acetaldehyde were the pollutants with the highest annual averages
by mass concentration for all four New Jersey sites.
• NATA-modeled concentrations of formaldehyde and acetaldehyde were fairly similar
to the annual averages, but were not necessarily the highest modeled concentrations.
• For ELNJ, xylenes had the highest NATA-modeled concentration. While
formaldehyde had the highest concentration for NBNJ, benzene was a close second.
The following observations can be made about risk from Table 18-7:
• Carbon tetrachloride had the highest theoretical cancer risk for CANJ, CFINJ, and
NBNJ, generally around 9 in-a-million; acetaldehyde had the highest theoretical
cancer risk for ELNJ (12.47 in-a-million).
18-44
-------
Table 18-7. Chronic Risk Summary for the Monitoring Sites in New Jersey
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(Hg/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Camden, New Jersey (CANJ) - Census Tract ID 34007601500
Acet aldehyde
Acrolein
Acrylonitrile
Benzene
Bromomethane
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
1,2-Dichloroethane
Dichloromethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Methyl- Tert-Butyl Ether
Tetrachloroethylene
Trichloroethylene
0.0000022
NR
0.000068
0.0000078
NR
0.00003
0.000015
0.000011
0.000026
0.00000047
5.5E-09
0.000022
NR
0.0000059
0.000002
0.009
0.00002
0.002
0.03
0.005
0.002
0.04
0.8
2.4
1
0.0098
0.09
o
6
0.27
0.6
2.50
0.19
0.01
1.91
0.29
0.18
0.22
0.09
0.04
0.79
2.45
<0.01
2.30
0.23
0.15
5.50
NR
0.07
14.87
NR
5.37
3.30
1.00
1.05
0.37
0.01
0.03
NR
1.38
0.31
0.28
9.63
0.01
0.06
0.06
0.09
0.01
O.01
O.01
0.01
0.25
O.01
O.01
0.01
0.01
2.04 ±0.23
0.63 ±0.14
0.09 ±0.04
1.16±0.13
0.43 ±0.16
0.13 ±0.03
0.61 ±0.05
0.21 ±0.03
0.03 ±O.01
0.97 ±0.7
3. 54 ±0.47
0.07 ±0.01
0.82 ±0.34
0.32 ±0.05
0.42 ±0.2
4.48
NR
6.23
9.02
NR
3.79
9.18
2.29
0.79
0.46
0.02
1.58
NR
1.86
0.84
0.23
31.44
0.05
0.04
0.09
0.06
0.02
O.01
O.01
0.01
0.36
O.01
O.01
0.01
0.01
Chester, New Jersey (CHNJ) - Census Tract ID 34027045901
Acet aldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
Chloromethylbenzene
£>-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000049
0.000011
0.000026
5.5E-09
0.000022
0.009
0.00002
0.002
0.03
0.002
0.04
NR
0.8
2.4
0.0098
0.09
1.10
0.07
0.01
1.04
0.11
0.21
0.01
0.02
0.03
1.29
0.01
2.43
NR
0.03
8.08
3.43
3.12
0.01
0.24
0.77
0.01
0.03
0.12
3.34
0.01
0.03
0.06
0.01
NR
O.01
O.01
0.13
0.01
1.19±0.15
0.54 ±0.13
0.06 ±0.01
0.5 ±0.06
0.03 ±0.01
0.58 ±0.05
0.02 ±0.01
0.04 ±0.01
0.03 ±O.01
1.93 ±0.28
0.07 ±0.01
2.62
NR
4.29
3.89
0.91
8.76
0.8
0.44
0.8
0.01
1.63
0.13
27.1
0.03
0.02
0.02
0.01
NR
O.01
O.01
0.20
0.01
oo
-------
Table 18-7. Chronic Risk Summary for the Monitoring Sites in New Jersey (Continued)
Pollutant
Tetrachloroethylene
Cancer
URE
Oig/m3)
0.0000059
Noncancer
RfC
Oig/m3)
0.27
1999 NATA
Modeled
Concentration
(Hg/m3)
0.12
Cancer Risk
(in-a-
million)
0.72
Noncancer
Risk (HQ)
<0.01
2006 UATMP
Annual
Average
(Hg/m3)
0.13 ±0.03
Cancer
Risk (in-a-
million)
0.78
Noncancer
Risk (HQ)
O.01
Elizabeth, New Jersey (ELNJ) - Census Tract ID 34039030100
Acet aldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
1,2-Dichloroethane
Dichloromethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Methyl Tert-Butyl Ether
1, 1,2,2-Tetrachloroethane
Tetrachloroethylene
1, 1,2-Trichloroethane
Trichloroethylene
Xylenes
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
0.000026
0.00000047
5.5E-09
0.000022
NR
0.000058
0.0000059
0.000016
0.000002
NR
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
2.4
1
0.0098
0.09
o
6
NR
0.27
0.4
0.6
0.1
4.36
0.71
<0.01
3.38
0.54
0.21
0.07
0.04
0.71
5.60
<0.01
3.45
0.06
0.31
<0.01
0.12
6.20
9.59
NR
0.07
26.33
16.09
3.17
0.73
0.92
0.33
0.03
0.04
NR
3.26
1.82
<0.01
0.24
NR
0.48
35.46
<0.01
0.11
0.27
0.01
<0.01
<0.01
0.01
0.57
O.01
O.01
NR
0.01
O.01
O.01
0.06
5.67 ± 0.74
0.61 ±0.17
0.09 ±0.03
1.29 ±0.23
0.16 ±0.03
0.6 ±0.05
0.15 ±0.03
0.04 ±0.01
0.78 ±0.16
4.51 ±0.59
0.08 ±0.02
1.44 ±0.76
0.07 ± 0.04
0.36 ±0.1
0.02 ±O.01
0.09 ± 0.02
3. 58 ±0.78
12.47
NR
6.00
10.10
4.72
8.93
1.70
0.91
0.37
0.02
1.84
NR
3.87
2.12
0.29
0.19
NR
0.63
30.29
0.04
0.04
0.08
0.01
O.01
O.01
0.01
0.46
O.01
O.01
NR
0.01
O.01
O.01
0.04
New Brunswick, New Jersey (NBNJ) - Census Tract ID 34023006206
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
1,2-Dichloroethane
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
0.000026
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
2.4
1.98
0.15
0.01
2.26
0.28
0.21
0.04
0.04
4.36
NR
0.07
17.62
8.33
3.17
0.44
0.93
0.22
7.61
0.01
0.08
0.14
0.01
0.01
0.01
3. 35 ±0.49
0.43 ±0.13
0.12 ±0.05
0.67 ±0.09
0.06 ± 0.02
0.61 ±0.06
0.08 ±0.01
0.03 ±0.01
7.37
NR
8.03
5.21
1.7
9.16
0.90
0.84
0.37
21.67
0.06
0.02
0.03
0.02
0.01
0.01
oo
-------
Table 18-7. Chronic Risk Summary for the Monitoring Sites in New Jersey (Continued)
Pollutant
Formaldehyde
Hexachloro- 1 ,3 -butadiene
1, 1,2,2-Tetrachloroethane
Tetrachloroethylene
Cancer
URE
Oig/m3)
5.5E-09
0.000022
0.000058
0.0000059
Noncancer
RfC
Oig/m3)
0.0098
0.09
NR
0.27
1999 NATA
Modeled
Concentration
(Hg/m3)
2.28
0.01
0.06
0.20
Cancer Risk
(in-a-
million)
0.01
0.03
3.20
1.21
Noncancer
Risk (HQ)
0.23
0.01
NR
O.01
2006 UATMP
Annual
Average
(Hg/m3)
2.58 ±0.76
0.11 ±0.06
0.05 ±O.01
0.26 ±0.10
Cancer
Risk (in-a-
million)
0.01
2.41
2.71
1.53
Noncancer
Risk (HQ)
0.26
0.01
NR
O.01
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
oo
-------
• According to NAT A, the benzene cancer risk was highest near each of the sites,
ranging from 8.08 in-a-million for CHNJ to 26.33 in-a-million near ELNJ.
• The cancer risk due to carbon tetrachloride was comparatively lower (roughly 3 in-a-
million near each site), according to NATA.
• Acrolein exhibited the highest noncancer risk HQ (based on annual averages) at all
four sites, ranging from 21.67 for NBNJ to 31.44 for CANJ. All other noncancer
HQs were less than 1.00.
• Acrolein also had the highest noncancer risk HQ according to NATA, although the
range was much broader (3.34 for CHNJ to 35.46 for ELNJ). Similar to the annual
average-based HQs, all other NATA-modeled noncancer HQs were less than 1.00.
18.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 18-8 and 18-9 present a
risk-based assessment of county-lev el emissions based on cancer and noncancer toxicity,
respectively. Table 18-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 18-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. In addition, the highest cancer and noncancer risks based on annual
averages are limited to those pollutants failing at least one screen.
The following observations can be made from Table 18-8:
• Benzene, formaldehyde, and dichloromethane were the highest emitted pollutants (by
mass) with cancer risk factors in each of the New Jersey counties.
• Benzene, 1,3-butadiene, and naphthalene had the highest cancer toxicity-weighted
emissions in Camden, Union, and Middlesex Counties; benzene, lead, and 1,3-
butadine had the highest cancer toxicity-weighted emissions in Morris County.
18-48
-------
Table 18-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in New Jersey
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer
Risk
(in-a-
million)
Camden, New Jersey (CANJ) - Camden County
Benzene
Formaldehyde
Dichloromethane
Acetaldehyde
Tetrachloroethylene
1 ,3 -Dichloropropene
1,3 -Butadiene
Naphthalene
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15 -PAH
216.15
151.44
54.85
40.92
38.60
36.96
28.64
19.40
19.09
2.99
Benzene
1,3 -Butadiene
Naphthalene
Tetrachloroethylene
£>-Dichlorobenzene
Lead
Poly cyclic Organic Matter as 15 -PAH
1 , 3 -Dichloropropene
Polycyclic Organic Matter as 7-PAH
Poly cyclic Organic Matter as non-15 PAH
1.69E-03
8.59E-04
6.59E-04
2.28E-04
2.10E-04
1.68E-04
1.65E-04
1.48E-04
1.10E-04
9.79E-05
Carbon Tetrachloride
Benzene
Acrylonitrile
Acetaldehyde
1,3 -Butadiene
£>-Dichlorobenzene
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
Trichloroethylene
1 ,2-Dichloroethane
9.18
9.02
6.23
4.48
3.79
2.29
1.86
1.58
0.84
0.79
Chester, New Jersey (CHNJ) - Morris County
Benzene
Formaldehyde
Dichloromethane
Acetaldehyde
1,3 -Butadiene
1 ,3 -Dichloropropene
Tetrachloroethylene
Naphthalene
£>-Dichlorobenzene
Trichloroethylene
315.27
152.06
55.40
48.39
45.64
34.56
30.16
20.88
17.86
17.30
Benzene
Lead
1,3 -Butadiene
Naphthalene
Nickel
£>-Dichlorobenzene
Tetrachloroethylene
Polycyclic Organic Matter as 15 -PAH
1 , 3 -Dichloropropene
Hexavalent Chromium
2.46E-03
1.82E-03
1.37E-03
7.10E-04
2.54E-04
1.96E-04
1.78E-04
1.49E-04
1.38E-04
1.32E-04
Carbon Tetrachloride
Acrylonitrile
Benzene
Acetaldehyde
Hexachloro- 1 ,3 -butadiene
1,3 -Butadiene
1,2-Dichloroethane
Chloromethylbenzene
Tetrachloroethylene
/>-Dichlorobenzene
8.76
4.29
3.89
2.62
1.63
0.91
0.80
0.80
0.78
0.44
oo
.u
VO
-------
Table 18-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in New Jersey (Continued)
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(Cmmtv-T ,evel)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer
Risk
(in-a-
million)
Elizabeth, New Jersey (ELNJ) - Union County
Benzene
Formaldehyde
Dichloromethane
Tetrachloroethylene
Acetaldehyde
1 ,3 -Dichloropropene
1,3 -Butadiene
Naphthalene
£>-Dichlorobenzene
Trichloroethylene
237.32
123.12
76.45
42.46
41.67
38.31
30.88
20.99
19.81
4.57
Benzene
1,3 -Butadiene
Naphthalene
Nickel
Lead
Tetrachloroethylene
£>-Dichlorobenzene
Arsenic
Poly cyclic Organic Matter as 15 -PAH
1 ,3 -Dichloropropene
1.85E-03
9.26E-04
7.14E-04
3.47E-04
2.86E-04
2.51E-04
2.18E-04
1.74E-04
1.55E-04
1.53E-04
Acetaldehyde
Benzene
Carbon Tetrachloride
Acrylonitrile
1,3 -Butadiene
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Hexachloro- 1 , 3 -butadiene
£>-Dichlorobenzene
1 ,2-Dichloroethane
12.47
10.10
8.93
6.00
4.72
3.87
2.12
1.84
1.70
0.91
New Brunswick, New Jersey (NBNJ) - Middlesex County
Benzene
Formaldehyde
Dichloromethane
Acetaldehyde
Tetrachloroethylene
1,3 -Butadiene
1 ,3 -Dichloropropene
Naphthalene
£>-Dichlorobenzene
Trichloroethylene
397.48
209.33
108.94
68.23
59.97
56.40
55.98
32.48
28.95
7.55
Benzene
1,3 -Butadiene
Naphthalene
Tetrachloroethylene
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15 -PAH
1 , 3 -Dichloropropene
Polycyclic Organic Matter as 7-PAH
Lead
Acetaldehyde
3.10E-03
1.69E-03
1.10E-03
3.54E-04
3.18E-04
2.34E-04
2.24E-04
1.71E-04
1.65E-04
1.50E-04
Carbon Tetrachloride
Acrylonitrile
Acetaldehyde
Benzene
1 , 1 ,2,2-Tetrachloroethane
Hexachloro- 1 ,3 -butadiene
1,3 -Butadiene
Tetrachloroethylene
£>-Dichlorobenzene
1 ,2-Dichloroethane
9.16
8.03
7.37
5.21
2.71
2.41
1.70
1.53
0.90
0.84
oo
(!/i
o
-------
Table 18-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in New Jersey
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk
(HQ)
Camden, New Jersey (CANJ) - Camden County
Toluene
Methyl Tert-Butyl Ether
Xylenes
Benzene
Formaldehyde
Methyl Isobutyl Ketone
Methyl Ethyl Ketone
1,1,1 -Trichloroethane
Hexane
Ethylbenzene
688.19
525.70
465.64
216.15
151.44
135.73
132.62
120.76
94.41
90.29
Acrolein
Formaldehyde
1,3 -Butadiene
Bromomethane
Manganese
Benzene
Naphthalene
Cyanide
Xylenes
Acetaldehyde
361,545.39
15,452.86
14,318.98
10,308.65
7,204.85
6,465.67
4,656.44
4,546.24
Acrolein
Formaldehyde
Acetaldehyde
Bromomethane
1,3 -Butadiene
Acrylonitrile
Benzene
Carbon Tetrachloride
Tetrachloroethylene
Dichloromethane
31.44
0.36
0.23
0.09
0.06
0.05
0.04
0.02
0.00
0.00
Chester, New Jersey (CHNJ) - Morris County
Toluene
Methyl Tert-Butyl Ether
Xylenes
Benzene
Formaldehyde
Ethylbenzene
Methyl Ethyl Ketone
Hexane
Methyl Isobutyl Ketone
1,1,1 -Trichloroethane
922.39
793.79
666.41
315.27
152.06
140.78
132.19
131.51
115.88
109.17
Acrolein
Nickel
1,3 -Butadiene
Formaldehyde^ s q7
Benzene
Bromomethane
Naphthalene
Xylenes 6 433 60
Cyanide
Acetaldehyde
413,407.46
24,375.66
22,819.77
15,516.30
10,509.00
9,639.60
6,961.21
6,664.10
5,943.86
5,376.71
Acrolein
Formaldehyde
Acetaldehyde
Acrylonitrile
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Hexachloro- 1 , 3 -butadiene
Tetrachloroethylene
/>-Dichlorobenzene
27.10
0.20
0.13
0.03
0.02
0.02
0.01
0.00
0.00
0.00
oo
-------
Table 18-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in New Jersey (Continued)
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk
(HQ)
Elizabeth, New Jersey (ELNJ) - Union County
Toluene
Xylenes
Methyl Tert-Butyl Ether
Hexane
Benzene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Formaldehyde
1,1,1 -Trichloroethane
Ethylbenzene
781.12
554.95
517.91
320.83
237.32
200.58
182.99
123.12
122.57
107.78
Acrolein
Nickel
1,3 -Butadiene
Formaldehyde
Bromomethane
Benzene
Naphthalene
Cyanide
Chlorine
Xylenes
349,882.79
33,390.25
15,440.19
12,563.54
10,687.32
7,910.75
6,996.30
6,605.69
5,812.50
5,549.51
Acrolein
Acetaldehyde
Formaldehyde
1,3 -Butadiene
Acrylonitrile
Benzene
Xylenes
Carbon Tetrachloride
Tetrachloroethylene
Hexachloro- 1 , 3 -butadiene
30.29
0.63
0.46
0.08
0.04
0.04
0.04
0.01
0.00
0.00
New Brunswick, New Jersey (NBNJ) - Middlesex County
Toluene
Methyl Tert-Butyl Ether
Xylenes
Benzene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Hexane
Formaldehyde
Ethylbenzene
1,1,1 -Trichloroethane
1,301.53
966.10
907.17
397.48
267.14
255.93
223.35
209.33
181.85
177.19
Acrolein
1,3 -Butadiene
Formaldehyde
Manganese
Bromomethane
Benzene
Naphthalene
Cyanide
Xylenes
Acetaldehyde
589,734.26
28,201.19
21,360.14
18,284.10
15,616.28
13,249.34
10,828.14
9,484.14
9,071.74
7,580.81
Acrolein
Acetaldehyde
Formaldehyde
Acrylonitrile
1,3 -Butadiene
Benzene
Carbon Tetrachloride
Hexachloro- 1 , 3 -butadiene
Tetrachloroethylene
/>-Dichlorobenzene
21.67
0.37
0.26
0.06
0.03
0.02
0.02
0.00
0.00
0.00
oo
(!/i
to
-------
• Neither formaldehyde nor dichloromethane appeared on the highest cancer toxicity-
weighted emissions list, and none of these pollutants had the highest cancer risks
based on the 2006 annual averages for any of the New Jersey monitoring sites.
• Instead, carbon tetrachloride (for CANJ, CHNJ, and NBNJ) and acetaldehyde (for
ELNJ) have the highest cancer risks based on the 2006 annual averages. While
carbon tetrachloride was neither one of the highest emitted nor one of the most toxic
based on the 2002 NEI emission inventory, acetaldehyde was one of the top five
highest emitted pollutants in the New Jersey counties.
The following observations can be made from Table 18-9:
• Although toluene, methyl tert-buty\ ether, and xylenes were the highest emitted
pollutants (by mass) with noncancer risk factors in each New Jersey county, only
total xylenes appeared on the top 10 noncancer toxi city-weighted emissions lists.
• With the exception of xylenes for ELNJ, none of these pollutants ranked on any of
the highest annual average-based noncancer risks lists.
• Acrolein had the highest noncancer toxicity-weighted emissions in each New Jersey
County and had the highest noncancer risks based on the 2006 annual average for all
four sites, but did not appear in the list of highest emitted pollutants.
New Jersey Pollutant Summary
• The pollutants of interest common to each of the New Jersey sites were acetaldehyde,
acrolein, benzene, 1,3-butadiene, carbon tetrachloride, formaldehyde, and
tetrachloroethylene.
• Formaldehyde and acetaldehyde had the highest daily averages for all four sites.
• Acrolein exceeded the short-term risk factors at all four New Jersey sites.
• A comparison of formaldehyde, benzene and 1,3-butadiene concentrations for all years
of UATMP participation shows that concentrations of benzene and 1,3-butadiene have
generally changed little at these sites. Formaldehyde concentrations seem to vary more
from year to year, although an overall decreasing trend is evident at CHNJ.
18-53
-------
19.0 Sites in North Carolina
This section presents meteorological, concentration, and spatial trends for the UATMP
sites in North Carolina (CANC and RTPNC). CANC is a rural site located in Candor near the
Uwharrie National Forest. RTPNC is an urban site located in the Research Triangle Park area
near Durham, North Carolina. Figures 19-1 and 19-2 are topographical maps showing the
monitoring sites in their rural and urban locations. Figures 19-3 and 19-4 identify point source
emission locations within 10 miles of these sites as reported to the 2002 NEI for point sources.
The CANC site has few sources nearby, most of which are located to the north or west of the
site. The majority of sources are involved in lumber and wood products production and fuel
combustion processes. The RTPNC site has a few more nearby sources, mostly to the north and
east, and the majority are involved in fuel combustion processes and industrial machinery and
equipment operations.
Candor is located in south-central North Carolina, about halfway between Charlotte and
Fayetteville, near the Uwharrie National Forest. This area is considered the Sandhills region,
where the sandy soil allows for rapid drainage, as well as rapid warming during the day and
cooling during the night. As a result, daytime temperatures rise quickly, while nighttime
temperatures cool quickly. Research Triangle Park is located between Raleigh and Durham in
central North Carolina. Its Southeastern location allows for warm, usually humid summers and
mild winters. The Mid-Atlantic location of these sites allows for fairly ample rainfall.
Afternoon thunderstorms are typical during the summer, although rainfall is distributed rather
equally throughout the year (Ruffner and Bair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the CANC and RTPNC monitoring sites are the Moore County Airport and Raleigh-Durham
International Airport (WBAN 3720 and 13722, respectively). Table 19-1 presents the average
meteorological conditions of temperature (average maximum and average), moisture (average
dew point temperature, average wet-bulb temperature, and average relative humidity),
19-1
-------
Figure 19-1. Candor, North Carolina (CANC) Monitoring Site
i P j/ i&
¥^ .("\ f iX '
£ m.. t
•
T)/x I
^~ . '^ •
K,
My-ilni
'•
:s ' ^
.-A' ^••-'" ' '-^' WW' -^
'/'
.. „ CANC ^
• Ifef 5
-] L->Cf - • M
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
19-2
-------
Figure 19-2. Research Triangle Park, North Carolina (RTPNC) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24, 000.
19-3
-------
Figure 19-3. Facilities Located Within 10 Miles of CANC
Montgomery County '
Moore
County
Stanly
County
S D
Richmond
County
Note; Due to facilfty density and collocation, the total facilities
displayed may not represent all facilities within (he area of interest.
Legend
••& CANC UATMP site
•'_ 10 mile radius
[ County boundary
Source Category Group (No. of Facilities)
D Fabricated Metal Products Facility (1)
F Fuel Combustion Industrial Facility (4)
f Integrated Iron & Steel Manufacturing Facility (1)
S Lumber & Wood Products Facility (3)
S Surface Coating Processes Industrial Facility (2)
f Waste Treatment & Disposal Industrial Facility (1)
19-4
-------
Figure 19-4. Facilities Located Within 10 Miles of RTPNC
•j'z
Durham
CcunEy
Orange
County
... 8 f
Chatham
County
. -Q-
Wake
County
Note: Due to facility density and collocation, the total facilities
displayed may not represent all facilities within the area of interest
Legend
•jjJr RTPNC UATMP site
10 mile radius
County boundary
Source Category Group (No. of Facilities)
c Chemicals & Allied Products Facility (1)
z Electrical & Electronic Equipment Facility (1)
F Fuel Combustion Industrial Facility (8)
J Industrial Machinery & Equipment Facility (4)
B Mineral Products Processing Industrial Facility (3)
> Pharmaceutical Production Processes Industrial Facility (3)
Q Primary Metal Industries Facility (1)
Y Rubber & Miscellaneous Plastic Roducts Facility (1)
u Stone, Clay, Glass. & Concrete Products (1)
s Surface Coating Processes Industrial Facility (1)
r Wholesale Trade (1)
19-5
-------
Table 19-1. Average Meteorological Conditions near the Monitoring Sites in North Carolina
Site
CANC
RTPNC
WBAN
03720
13722
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
72.05
±1.47
67.00
±8.59
71.92
±1.46
67.89
±7.98
Average
Temperature
(°F)
60.90
±1.47
58.20
±6.91
61.11
± 1.43
57.56
±6.89
Average
Dew Point
Temperature
(»F)
47.85
±1.70
44.42
±9.83
48.51
±1.70
43.81
±9.18
Average
Wet Bulb
Temperature
(°F)
54.17
±1.41
51.55
±7.06
54.61
±1.39
50.91
±6.77
Average
Relative
Humidity
(%)
65.74
±1.34
65.92
± 14.83
66.97
±1.35
65.27
±4.92
Average
Sea Level
Pressure
(mb)
NA1
NA1
1017.19
±0.66
1016.47
±4.43
Average
Scalar Wind
Speed
(kt)
4.86
±0.28
6.06
±1.77
5.19
±0.28
6.86
±1.31
NA = Sea level pressure was not recorded at this station.
-------
pressure (average sea level pressure), and wind information (average scalar wind speed) for the
entire year and on days samples were collected. Also included in Table 19-1 is the 95 percent
confidence interval for each parameter. As shown in Table 19-1, temperatures on sampling days
appeared cooler than temperatures experienced throughout the year. This difference is probably
attributable to the sampling duration of these sites. Both CANC and RTPNC stopped sampling in
June, thereby missing the warmest months of the year. The weather station at Moore County Airport
did not record sea level pressure; therefore it is not presented in Table 19-1.
19.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Michigan
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of interest
is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each measured pollutant
concentration was compared to a risk screening value. A total of 81 HAPs are listed in the EPA
guidance as having risk screening values. If the daily concentration value was greater than the risk
screening value, then the measured concentration "failed the screen." Pollutants of interest are those
in which the individual pollutant's total failed screens contribute to the top 95 percent of the site's
total screens. The North Carolina sites sampled for carbonyl compounds only. Table 19-2 presents
the pollutants that failed at least one screen at the North Carolina monitoring sites.
Table 19-2. Comparison of Measured Concentrations and EPA Screening
Values for the North Carolina Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Candor, North Carolina - CANC
Acetaldehyde
Formaldehyde
Total
8
6
14
9
9
18
88.89
66.67
77.78
57.14
42.86
57.14
100.00
Durham, North Carolina - RTPNC
Acetaldehyde
Formaldehyde
Total
9
6
15
9
9
18
100.00
66.67
83.33
60.00
40.00
60.00
100.00
19-7
-------
The following observations are shown in Table 19-2:
• Acetaldehyde and formaldehyde failed screens at the CANC and RTPNC monitoring
sites.
• These two pollutants failed a total of 14 screens at CANC and 15 screens at RTPNC.
• Acetaldehyde contributed to over 50 percent of the total failed screens for both sites.
• Acetaldehyde concentrations failed more than 85 percent of its screens at CANC and 100
percent at RTPNC. Formaldehyde concentrations failed nearly 70 percent of its screens
at RTPNC and CANC.
19.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average concentration
of all measured detections. If there were at least seven measured detections within each season, then
a seasonal average was calculated. The seasonal average includes 1/2 MDLs substituted for all non-
detects. A seasonal average was not calculated for pollutants with less than seven measured
detections in a respective season. Finally, the annual average is the average concentration of all
measured detections and 1/2 MDLs substituted for non-detects. The resulting daily average
concentrations may therefore be inherently higher than the annual average concentrations where 1/2
MDLs replacing non-detects are incorporated into the average. Annual averages were calculated for
monitoring sites where sampling began no later than February and ended no earlier than November.
The daily and seasonal average concentrations are presented in Table 19-3. Annual averages are
presented and discussed in further detail in later sections.
The following observations are shown in Table 19-3:
• Acetaldehyde and formaldehyde were detected in every sample collected at the North
Carolina monitoring sites.
• The daily average of formaldehyde was higher than acetaldehyde for both sites, but if the
confidence interval was considered, the concentrations were not significantly different.
• Winter and spring seasonal averages for these two pollutants could not be calculated due
to the low number of measured detections (these sites sampled a l-in-12 schedule).
Summer and autumn averages could not be calculated because the sites stopped sampling
in June.
19-8
-------
Table 19-3. Daily and Seasonal Averages for the Pollutants of Interest for the North Carolina Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
frig/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Hg/m3)
Conf.
Int.
Autumn
Avg
(Hg/m3)
Conf.
Int.
Candor, North Carolina - CANC
Acetaldehyde
Formaldehyde
9
9
9
9
1.03
1.66
0.27
0.61
NR
NR
NR
NR
NR
NR
NR
NR
NA
NA
NA
NA
NA
NA
NA
NA
Durham, North Carolina - RTPNC
Acetaldehyde
Formaldehyde
9
9
9
9
1.19
2.17
0.26
0.77
NR
NR
NR
NR
NR
NR
NR
NR
NA
NA
NA
NA
NA
NA
NA
NA
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
-------
19.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for the North Carolina monitoring sites was
evaluated using ATSDR short-term (acute) and intermediate MRL and California EPA acute REL
factors. Acute risk is defined as exposures from 1 to 14 days while intermediate risk is defined as
exposures from 15 to 364 days. It is useful to compare the preprocessed daily measurements to the
short-term MRL and REL factors, as well as compare seasonal averages to the intermediate MRL.
Of the two pollutants with at least one failed screen at either site, none of the concentrations
exceeded the acute risk values. Intermediate risk could not be assessed because seasonal averages
could not be calculated.
19.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following meteorological
analyses: Pearson correlation coefficients between meteorological parameters (such as temperature)
and concentrations of the pollutants of interest; sample-year composite back trajectories; and
sample-year wind roses.
19.4.1 Pearson Correlation Analysis
Table 19-4 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the North Carolina monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered from Table 19-4:
• Strong negative correlations were calculated between formaldehyde and acetaldehyde
and relative humidity for both sites. This indicates that these pollutant's concentrations
tend to increase as moisture content decreases.
• Strong positive correlations were exhibited between formaldehyde and maximum and
average temperature for both sites, indicating that formaldehyde concentrations tend to
increase as temperature increases.
• The low number of measured detections at these sites may make the correlations appear
stronger than they would otherwise.
19-10
-------
Table 19-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for
the North Carolina Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Candor, North Carolina - CANC
Acetaldehyde
Formaldehyde
9
9
0.35
0.81
0.04
0.56
-0.49
-0.02
-0.27
0.26
-0.81
-0.64
NA
NA
0.46
0.21
Durham, North Carolina - RTPNC
Acetaldehyde
Formaldehyde
9
9
0.39
0.66
0.29
0.62
-0.32
0.05
-0.04
0.35
-0.83
-0.62
0.16
0.09
0.19
-0.17
NA = This station did not record sea level pressure.
-------
19.4.2 Composite Back Trajectory Analysis
Figures 19-5 and 19-6 are composite back trajectory maps for the North Carolina monitoring
sites for the days on which sampling occurred. Each line represents the 24-hour trajectory along
which a parcel of air traveled toward the monitoring site on a sampling day. Each concentric circle
around the site represents 100 miles.
The following observations can be made from Figure 19-5:
• Back trajectories originated from a variety of directions at CANC, although there was an
absence of trajectories from the east.
• The 24-hour airshed domain was large, with trajectories originating as far away as
northern Illinois (> 700 miles).
• Over 70 percent of the trajectories originated within 400 miles of the CANC monitoring
site.
• The back trajectory map might look much different with a full year's worth of sampling
day trajectories.
The following observations can be made from Figure 19-6:
• Back trajectories originated from a variety of directions at RTPNC, although there was an
absence of trajectories from the east.
• The 24-hour airshed domain was large, with trajectories originating as far away as
Wisconsin (>700 miles).
• Nearly 70 percent of the trajectories originated within 400 miles of the site.
• Figure 19-6 might look much different with a full year's worth of sampling day
trajectories.
19.4.3 Wind Rose Analysis
Hourly wind data from the Moore County Airport and Raleigh-Durham International Airport
weather stations were uploaded into a wind rose software program, WRPLOT (Lakes, 2006).
WRPLOT produces a graphical wind rose from the wind data. A wind rose shows the frequency of
wind directions about a 16-point compass, and uses different shading to represent wind speeds.
19-12
-------
Figure 19-5. Composite Back Trajectory Map for CANC
-------
Figure 19-6. Composite Back Trajectory Map for RTPNC
-------
Figures 19-7 and 19-8 are the wind roses for the North Carolina monitoring sites on days that
sampling occurred.
Observations from Figure 19-7 for CANC include:
• Hourly winds were predominantly out of the west-southwest (16 percent of observations),
southwest (15 percent), and west (15 percent) on days samples were collected near
CANC.
• Calm winds (<2 knots) were recorded for 14 percent of the hourly observations.
• For wind speeds greater than two knots, most of the observations ranged from 7 to 11
knots.
Observations from Figure 19-8 for RTPNC include:
• Hourly winds were predominantly out of southwest (16 percent), south-southwest (14
percent), and west-southwest (13 percent) on days samples were collected near RTPNC.
• Calm winds (<2 knots) were recorded for 12 percent of the hourly observations.
• For wind speeds greater than two knots, most of observations ranged from 7 to 11 knots.
19.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could not
be performed as ERG did not analyze VOCs for this site. A mobile tracer analysis could not be
performed as this site did not sample for SNMOC.
19.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Montgomery County and Durham
County, North Carolina were obtained from the North Carolina Department of Transportation and
the U.S. Census Bureau, and are summarized in Table 19-5. Table 19-5 also includes a vehicle
registration to county population ratio (vehicles per person). In addition, the population within 10
miles of each site is presented. An estimation of 10-mile vehicle registration was computed using
the 10-mile population surrounding the monitor and the vehicle registration ratio. Finally,
19-15
-------
Figure 19-7. Wind Rose for CANC Sampling Days
SOUTH --'
WIND SPEED
(Knots)
I | >=22
I I 17 - 21
• 11 - 17
^| 7- 11
I I A- 7
^| 2- 4
Calms: 13.97%
-------
Figure 19-8. Wind Rose for RTPNC Sampling Days
NORTH"---.
VO
SOUTH .---
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
^| 11 - 17
I I 4- 7
• 2- 4
Calms: 11.79%
-------
Table 19-5. Motor Vehicle Information for the North Carolina Monitoring Sites
Site
CANC
RTPNC
2006 Estimated
County
Population
27,638
246,896
Number of
Vehicles Registered
28,333
188,168
Vehicles per Person
(Registration:
Population)
1.03
0.76
Population
Within 10 Miles
11,369
399,239
Estimated 10 Mile
Vehicle Ownership
11,655
304,274
Traffic Data
(Daily
Average)
100
12,000
VO
oo
-------
Table 19-5 contains the average daily traffic information, which represents the average number of
vehicles passing the monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 19-5 include:
• The CANC monitoring site has a significantly lower county-level and 10-mile population
and vehicle ownership than RTPNC. CANC also has a significantly lower daily traffic
volume than RTPNC. This is expected as the CANC site is located within the boundaries
of a National Forest, while RTPNC is located in a business park near a major interstate,
as shown in Figures 19-1 and 19-2.
• The CANC site's vehicles per person ratio is higher than the RTPNC ratio, and is over
1.0.
• Compared to other UATMP locations, CANC has one of the lowest daily traffic volumes,
with only three monitoring sites reporting a smaller daily traffic volume, while RTPNC's
daily traffic volume falls in the middle of the range.
19.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the 2006
program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was conducted.
Details on how this analysis was conducted can be found in Section 3.3.4. The CANC monitoring
site has participated in the UATMP since 2003 and the RTPNC site has participated in the UATMP
since 2004. As previously mentioned, these sites sampled for only carbonyl compounds. Figures
19-9 and 19-10 present the trends analysis for formaldehyde.
The following observations can be made from Figures 19-9 and 19-10:
• Formaldehyde concentrations have changed little over the last four years for CANC.
• The RTPNC monitoring site also appears to have a fairly consistent formaldehyde
concentration.
19.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at the
North Carolina sites. The North Carolina sites did not sample long enough to allow calculation of
annual averages for the pollutants of interest (refer to Section 3.3.5 regarding the definition of an
19-19
-------
to
o
Q.
Q.
O
+J
03
-------
Figure 19-10. Comparison of Yearly Averages for the RTPNC Monitoring Site
to
2.5
Q.
Q.
2
S 1.5
o
o
o
o
U)
03
5 1
0.5
2004
2005
Year
2006
D Formaldehyde
-------
annual average), and therefore annual average-based cancer and not cancer risks cannot be assessed.
However, data from EPA's 1999 NATA were retrieved and are presented in Table 19-6. The NATA
data are presented for the census tract where the monitoring sites are located.
The census tract information for the North Carolina sites is as follows:
• The census tract for CANC is 37123960500, which had a population of 6,424 and
represents approximately 24 percent of the Montgomery County population in 2000.
• The census tract for RTPNC is 37063002014, which had a population of 5,034, and
represents approximately 2.3 percent
The following observations can be made from Table 19-6:
• The NATA-modeled concentrations of acetaldehyde and formaldehyde were higher for
RTPNC than for CANC, although both were relatively low.
• Cancer risks attributable to acetaldehyde were significantly higher than those of
formaldehyde for both North Carolina sites.
• NATA-modeled noncancer risks of formaldehyde and acetaldehyde were very low for
both sites.
19.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 19-7 and 19-8 present a risk-
based assessment of county-level emissions based on cancer and noncancer toxicity, respectively.
Table 19-7 presents the 10 pollutants with the highest emissions from the 2002 NEI and the 10
pollutants with the highest toxicity-weighted emissions. The 10 pollutants with the highest cancer
risk could not be calculated because there are no annual averages. Table 19-8 presents similar
information, but is based on noncancer risk factors. The pollutants in these tables are limited to
those that have cancer and noncancer risk factors, respectively. As a result, the highest emitted
pollutants in the cancer table may not be the same as the noncancer tables, although the actual value
of the emissions will be.
19-22
-------
Table 19-6. Chronic Risk Summary for the Monitoring Sites in North Carolina
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Candor, North Carolina (CANC) - Census Tract ID 37123960500
Acetaldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
0.57
0.39
1.25
0.01
0.06
0.04
NA
NA
NA
NA
NA
NA
Durham, North Carolina (RTPNC) - Census Tract ID 37063002014
Acetaldehyde
Formaldehyde
0.0000022
5.5E-09
0.009
0.0098
1.21
1.24
2.65
0.01
0.13
0.13
NA
NA
NA
NA
NA
NA
BOLD indicates a pollutant of interest
NA = annual average not available
to
-------
Table 19-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in North Carolina
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based
on Annual Average
Concentration
(Site-Specific)
Cancer Risk
Pollutant (in-a-million)
Candor, North Carolina (CANC) - Montgomery County
Formaldehyde
Benzene
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Polycyclic Organic Matter as 7-PAH
Tetrachloroethylene
Naphthalene
Polycyclic Organic Matter as 15 -PAH
£>-Dichlorobenzene
55.44
50.17
7.96
3.01
2.24
2.11
1.66
1.18
0.80
0.64
Benzene
Polycyclic Organic Matter as 7-PAH
1,3 -Butadiene
Hexavalent Chromium
Polycyclic Organic Matter as 15 -PAH
Naphthalene
Arsenic
Polycyclic Organic Matter as non-15 PAH
Lead
Acetaldehyde
3.91E-04
1.39E-04
9.04E-05
5.36E-05
4.41E-05
4.01E-05
3.83E-05
2.32E-05
2.22E-05
1.75E-05
Durham, North Carolina (RTPNC) - Durham County
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
Dichloromethane
Trichloroethylene
Naphthalene
£>-Dichlorobenzene
Polycyclic Organic Matter as 15 -PAH
248.26
91.93
34.10
24.81
24.37
23.89
7.04
5.92
5.01
1.41
Benzene
1,3 -Butadiene
Naphthalene
Tetrachloroethylene
Ethylene Oxide
Beryllium
Hexavalent Chromium
Polycyclic Organic Matter as 15 -PAH
Acetaldehyde
Polycyclic Organic Matter as 7-PAH
1.94E-03
7.44E-04
2.01E-04
1.44E-04
1.12E-04
1.04E-04
8.43E-05
7.75E-05
7.50E-05
6.81E-05
VO
to
-------
Table 19-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in North Carolina
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Noncancer
Risk
Pollutant (HQ)
Candor, North Carolina - CANC - Montgomery County
Toluene
Formaldehyde
Benzene
Xylenes
Methanol
Ethylbenzene
Hexane
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Hydrochloric Acid
77.23
55.44
50.17
49.49
21.91
11.89
11.63
9.77
9.36
9.19
Acrolein
Manganese
Formaldehyde
Benzene
Chlorine
1,3 -Butadiene
Cyanide
Acetaldehyde
Xylenes
Hydrochloric Acid
68,961.80
19,022.29
5,657.29
1,672.47
1,544.23
1,505.90
982.21
884.62
494.92
459.64
Durham, North Carolina - RTPNC - Durham County
Toluene
Xylenes
Methanol
Benzene
Ethylene Glycol
Hexane
Methyl Ethyl Ketone
Ethylbenzene
Formaldehyde
Hydrochloric Acid
606.64
392.76
253.60
248.26
106.35
98.65
94.65
93.30
91.93
36.43
Acrolein
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Acetaldehyde
Cyanide
Beryllium
Naphthalene
Hydrochloric Acid
261,196.28
12,406.99
9,380.86
8,275.48
3,927.60
3,788.53
2,839.13
2,169.50
1,974.04
1,821.62
VO
to
-------
The following observations can be made from Table 19-7
• Unlike most UATMP counties, formaldehyde was the highest emitted pollutant (by mass)
with a cancer risk factor in Montgomery County, where CANC is located, while benzene
followed with the second highest emissions. However, the emissions for these pollutants
were very similar and rather low.
• Benzene had the highest emissions in Durham County, where RTPNC is located,
followed by formaldehyde. The emissions of these pollutants in Durham County were
higher than those of Montgomery County.
• Benzene had the highest cancer toxicity-weighted emissions in both counties, while
formaldehyde did not appear on either top 10 toxicity-weighted emissions lists.
• Benzene, acetaldehyde, 1,3-butadiene, POM as 7-PAH, naphthalene, and POM as 15-
PAH were shown on both "top 10" lists for Montgomery County, while benzene,
acetaldehyde, 1,3-butadiene, tetrachloroethylene, naphthalene, and POM as 15-PAH were
shown on both "top 10" lists for Durham County.
The following observations can be made from Table 19-8:
• Although toluene was the highest emitted pollutant (by mass) with a noncancer risk
factor in both Durham and Montgomery Counties, it did not rank in the top 10 based on
toxicity-weighted emissions.
• The toluene emissions in Durham County were much higher than those in Montgomery
County.
• Like most counties, acrolein had the highest noncancer toxicity-weighted emissions in
both counties, but was significantly higher in Durham County.
• Formaldehyde, benzene, and xylenes were the only pollutants that appear on both lists for
the two North Carolina counties.
North Carolina Pollutant Summary
The pollutants of interest common to both North Carolina sites were acetaldehyde and
formaldehyde.
Formaldehyde had the highest daily average for both sites.
A comparison of formaldehyde concentrations for all years of UATMP participation shows
that formaldehyde concentrations at CANC and RTPNC have changed little over the years.
19-26
-------
20.0 Sites in Oklahoma
This section presents meteorological, concentration, and spatial trends for the UATMP
sites in Oklahoma (CNEP, TOOK, TSOK and TUOK). TOOK, TSOK, and TUOK are located
in Tulsa, in northeast Oklahoma, while CNEP is located in Pryor, OK, approximately 30 miles
east of the other sites. Figures 20-1 through 20-4 are topographical maps showing the
monitoring sites in their urban and rural locations. Figures 20-5 and 20-6 identify point source
emission locations within 10 miles of these sites as reported to the 2002 NEI for point sources.
Only a small number of sources are located within a 10 mile radius of CNEP, as shown in Figure
20-5. The sources near this site are located mainly to the west and consist of mostly fuel
combustion processes. As shown in Figure 20-6, the three Tulsa sites reside within a mile or two
of each other. There are many sources located within 10 miles of the Tulsa sites, most of which
are located to the northeast and southwest of the sites. Fabricated metal products production
account for more than a dozen of the local processes.
Tulsa is located in northeast Oklahoma, just southeast of the Osage Indian Reservation,
and along the Arkansas River. The area is characterized by a continental climate, with warm and
humid summers and cool winters. The region experiences ample rainfall, with spring as the
wettest season. A southerly wind prevails, bringing warm, moist air northward from the Gulf of
Mexico. Pryor is also in northeast Oklahoma, approximately 30 miles east of Tulsa, so the
climate is much like that of Tulsa. Oklahoma is in "Tornado Alley", where severe thunderstorms
are capable of producing strong winds and hail, and tornadoes are more prevalent than in other
regions in the U.S. (Ruffner and Bair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the CNEP monitoring site is the Claremore Regional Airport; TOOK and TUOK are closest to
the Richard Lloyd Jones Jr. Airport; and TSOK is near the Tulsa International Airport (WBAN
53940, 53908, and 13968, respectively.) Table 20-1 presents the average meteorological
conditions of temperature (average maximum and average), moisture (average dew point
20-1
-------
Figure 20-1. Cherokee Nation, Oklahoma (CNEP) Monitoring Site
\/S , '* •"
?4$$
/.,.,
'?'-"'" / tf/rtffrj&f£^
S • : ; i_W jf/'Tfi / ,-^-j w
/ Oil ^ lf\x"^:) /- m£&2& • .-
iSp^/5 ^^^^- MT?4- ./
/ - .»! - '• . ' . •• "»' &, '"^w,-,,' ' .' .: *J 'Jl>"-••'•*- . X""--' '"* -
ii-'-f \ V: •( i ff, '^ ' "'•- "' /
' ^/;.-..," " mpl^^JI f*^v'j ; •' "" ijL
Sources: USGS 7.S Minute Series. Map Scale: 1:24,000.
20-2
-------
Figure 20-2. Tulsa, Oklahoma (TOOK) Monitoring Site
{(.&.• a.". .. • ,»'££-, ...,. »s*« ajswasii.^*
I iti^ptei^ •
."""i . ' 'W -i*S- ('* * V "" ^ '-^'•it'*i! *•* Jf't*
• i SS L^ _ A. '.w,' T * .aj^L -^-...*SC* VtttKS -^ j ,
r/ yf^y-jBwSB
Sources: USGS 7.5 Minute Series. Map Scale: 1:24,000.
20-3
-------
Figure 20-3. Tulsa, Oklahoma (TSOK) Monitoring Site
;>,.
.... I- ' -;- fu^lj
Sources: USGS 7.5 Minute Series. Map Scale: 1:24,000.
20-4
-------
Figure 20-4. Tulsa, Oklahoma (TUOK) Monitoring Site
Sources: USGS 7.5 Minute Series. Map Scale: 1:24,000.
20-5
-------
Figure 20-5. Facilities Located Within 10 Miles of CNEP
Mayes
CounEy
Rogers
County
Cherokee
Cqunty
Nose; Due to faoiltty density and collocation, the tc$al facilities
displayed may not represent aH facilities within the area of interest.
Legend
"& CNEP UATMP site
10 mile radius
! | County boundary
Source Category Group (No. of Facilities)
F Fuel Combustion Industrial Facility (3)
f Integrated Iron & Steel Manufacturing Facility (1)
B Mineral Products Processing Industrial Facility (1)
P Miscellaneous Processes Industrial Facility (1)
# Production of Inorganic Chemicals Industrial Facility (1)
4 Production of Organic Chemicals Industrial Facility (1}
;: Pulp & Paper Production Facility (2)
e Utility Boilers (1)
20-6
-------
Figure 20-6. Facilities Located Within 10 Miles of TOOK, TSOK and TUOK
Ccmty
Rogers
County
Tulsa
County
S ^ S T D
B ' T S
^_ 1_ I
8 si'
J
J D D
c - -s -
8
Creek
County
D ,
P
v-Jpf
Note; Due to faditty density and oollocatiw, the lota! facilities
displayed may not represent aU facilities within the area of interest.
Legend
"&• TOOK UATMP site r&j TUOK UATMP site
"A" TSOK UATMP site 10 mile radius
Source Category Group (No. of Facilities)
C Chemicals & Allied Products Facility (3)
z Electrical & Electronic Equipment Facility (1)
o Fabricated Metal Products Facility (13)
l Incineration Industrial Facility (1)
J Industrial Machinery & Equipment Facility (4)
«- Integrated Iron & Steel Manufacturing Facility (4)
Liquids Distribution Industrial Facility (2)
Mineral Products Processing Industrial Facility (2)
Miscellaneous Processes Industrial Facility (6)
County boundary
L
v Polymers & Resins Production Industrial Facility (2)
o Primary Metal Industries Facility (1)
Y Rubber & Miscellaneous Plastic Products Facility (2)
u Stone. Clay. Glass. & Concrete Products (2)
s Surface Coating Processes Industrial Facility (10)
T Transportation Equipment (2)
+ Transportation by Air (1)
a Utility Boilers (3)
''- Waste Treatment & Disposal Industrial Facility (4)
i- Wholesale Trade (2)
Petroleum/Nat. Gas Prod. & Refining industrial Facility (2)
20-7
-------
Table 20-1. Average Meteorological Conditions near the Monitoring Sites in Oklahoma
Site
CNEP
TOOK
TSOK
TUOK
WBAN
53940
53908
13968
53908
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
72.83
± 1.81
60.31
±7.53
74.67
±1.80
76.32
±4.57
74.27
±1.80
77.26
±6.30
74.67
±1.80
75.52
±4.62
Average
Temperature
(°F)
61.17
±1.71
49.23
±7.22
62.51
±1.74
63.91
±4.41
63.45
±1.75
66.62
±6.11
62.51
± 1.74
63.17
±4.46
Average
Dew Point
Temperature
(°F)
47.40
±1.74
37.79
±8.02
46.93
±1.73
49.70
±4.14
46.47
±1.72
50.90
±5.64
46.93
± 1.73
48.69
±4.30
Average
Wet Bulb
Temperature
(°F)
53.87
±1.54
44.08
±6.88
54.15
±1.52
55.96
±3.80
54.34
±1.50
57.63
±5.20
54.15
±1.52
55.22
±3.88
Average
Relative
Humidity
(%)
64.51
±1.31
67.71
±6.40
61.31
±1.33
64.13
±3.07
58.05
±1.41
60.84
±4.27
61.31
± 1.33
63.50
±3.14
Average
Sea Level
Pressure
(mb)
NA1
NA1
1016.63
±0.71
1016.50
±1.60
1015.41
±0.73
1016.61
±2.11
1016.63
±0.71
1016.74
±1.63
Average
Scalar Wind
Speed
(kt)
6.94
±0.33
5.88
±1.18
5.79
±0.28
5.71
±0.78
8.18
±0.34
7.22
±0.95
5.79
±0.28
5.79
±0.76
to
o
oo
Sea level pressure was not recorded at the Claremore Regional Airport.
-------
temperature, average wet-bulb temperature, and average relative humidity), pressure (average
sea level pressure), and wind information (average scalar wind speed) for the entire year and on
days samples were collected. Also included in Table 20-1 is the 95 percent confidence interval
for each parameter. Table 20-1 shows a large difference for CNEP between annual weather
conditions and those observed on sampling days. This site sampled only from September
through December, which can explain the wide disparity between the two sets of averages.
Table 20-1 shows little difference for the Tulsa sites between annual weather conditions and
those observed on sampling days.
20.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Michigan
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total screens. The CNEP site sampled for VOC only, while
TOOK, TSOK and TUOK sampled for VOC, carbonyl compounds, and metals. Table 20-2
presents the pollutants that failed at least one screen at the Oklahoma monitoring sites.
The following observations are shown in table 20-2:
• Five pollutants with a total of 49 measured concentrations failed screens at CNEP; 18
pollutants with a total of 354 measured concentrations failed screens at TOOK;
fourteen pollutants with a total of 242 measured concentrations failed screens at
TSOK; and 15 pollutants with a total of 252 measured concentrations failed screens at
TUOK.
• The pollutants of interest varied by site, yet the following four pollutants contributed
to the top 95 percent of the total failed screens at each Oklahoma monitoring site:
acrolein, benzene, 1,3-butadiene, and carbon tetrachloride.
• Acrolein, benzene, and carbon tetrachloride had 100 percent of their measured
detections fail screens at all of the sites.
20-9
-------
Table 20-2. Comparison of Measured Concentrations and EPA Screening
Values for the Oklahoma Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
%of
Total
Failures
Cumulative
%
Contribution
Cherokee Nation, Oklahoma - CNEP
Acrolein
Benzene
Carbon Tetrachloride
1,3 -Butadiene
1 ,2-Dichloroethane
Total
14
14
14
6
1
49
14
14
14
10
1
53
100.00
100.00
100.00
60.00
100.00
92.45
28.57
28.57
28.57
12.24
2.04
28.57
57.14
85.71
97.96
100.00
Tulsa, Oklahoma - Site 1 - TOOK
Acetaldehyde
Acrolein
Carbon Tetrachloride
Benzene
Formaldehyde
£>-Dichlorobenzene
1,3 -Butadiene
Tetrachloroethylene
Manganese (TSP)
Arsenic (TSP)
Xylenes
Nickel (TSP)
Cadmium (TSP)
Hexachloro- 1 ,3 -butadiene
1 ,2-Dichloroethane
Dichloromethane
Acrylonitrile
Chloromethane
Total
44
44
44
44
43
38
33
16
14
14
6
6
2
2
1
1
1
1
354
44
44
44
44
44
44
38
34
14
14
44
14
14
2
1
41
1
44
525
100.00
100.00
100.00
100.00
97.73
86.36
86.84
47.06
100.00
100.00
13.64
42.86
14.29
100.00
100.00
2.44
100.00
2.27
67.43
12.43
12.43
12.43
12.43
12.15
10.73
9.32
4.52
3.95
3.95
1.69
1.69
0.56
0.56
0.28
0.28
0.28
0.28
12.43
24.86
37.29
49.72
61.86
72.60
81.92
86.44
90.40
94.35
96.05
97.74
98.31
98.87
99.15
99.44
99.72
100.00
Tulsa, Oklahoma - Site 2 - TSOK
Acrolein
Benzene
Carbon Tetrachloride
Acetaldehyde
Formaldehyde
1,3 -Butadiene
/>-Dichlorobenzene
Arsenic (TSP)
Manganese (TSP)
Tetrachloroethylene
Xylenes
29
29
28
28
26
24
21
14
14
12
8
29
29
28
28
28
28
29
15
15
27
29
100.00
100.00
100.00
100.00
92.86
85.71
72.41
93.33
93.33
44.44
27.59
11.98
11.98
11.57
11.57
10.74
9.92
8.68
5.79
5.79
4.96
3.31
11.98
23.97
35.54
47.11
57.85
67.77
76.45
82.23
88.02
92.98
96.28
20-10
-------
Table 20-2. Comparison of Measured Concentrations and EPA Screening
Values for the Oklahoma Monitoring Sites (Continued)
Pollutant
Nickel (TSP)
Acrylonitrile
Cadmium (TSP)
Total
#of
Failures
5
3
1
242
#of
Measured
Detections
15
3
15
318
%of
Screens
Failed
33.33
100.00
6.67
76.10
%of
Total
Failures
2.07
1.24
0.41
Cumulative
%
Contribution
98.35
99.59
100.00
Tulsa, Oklahoma - Site 3 - TUOK
Acrolein
Carbon Tetrachloride
Benzene
Acetaldehyde
Formaldehyde
1,3 -Butadiene
Tetrachloroethylene
£>-Dichlorobenzene
Arsenic (TSP)
Manganese (TSP)
Hexachloro- 1 ,3 -butadiene
Xylenes
Acrylonitrile
Nickel (TSP)
1 ,2-Dichloroethane
Total
31
31
31
30
29
28
22
19
12
12
2
2
1
1
1
252
31
31
31
30
30
31
29
31
13
13
2
31
1
13
1
318
100.00
100.00
100.00
100.00
96.67
90.32
75.86
61.29
92.31
92.31
100.00
6.45
100.00
7.69
100.00
79.25
12.30
12.30
12.30
11.90
11.51
11.11
8.73
7.54
4.76
4.76
0.79
0.79
0.40
0.40
0.40
12.30
24.60
36.90
48.81
60.32
71.43
80.16
87.70
92.46
97.22
98.02
98.81
99.21
99.60
100.00
20.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects were incorporated into the
average. Annual averages were calculated for monitoring sites where sampling began no later
than February and ended no earlier than November. The daily and seasonal average
20-11
-------
concentrations are presented in Table 20-3. Annual averages are presented and discussed in
further detail in later sections.
The following observations for CNEP are shown in Table 20-3:
• Acrolein exhibited the highest daily average for CNEP.
• Spring and summer averages could not be calculated for CNEP because this site
began sampling in September; winter averages could not be calculated because there
were not enough measured detections in conjunction with the onset of sampling.
The following observations for the Tulsa sites are shown in Table 20-3:
• Xylenes had the highest daily averages for TOOK and TSOK, but this pollutant was
not a pollutant of interest for TUOK.
• Formaldehyde had similar daily averages across the Tulsa sites, as did 1,3-butadiene,
carbon tetrachloride, and/?-dichlorobenzene.
• The Tulsa sites had equipment problems at the onset of sampling. Additionally, the
original location of the TSOK site was problematic. The monitoring equipment was
moved to a new location and sampling resumed in June. As a result, seasonal
averages could not be calculated for many of the pollutants for winter and spring. In
addition, metals sampling did not begin until October, which would only allow for
autumn averages to be calculated. However, a few seasonal trends can still be
identified.
• Formaldehyde was highest in the summer for all three Tulsa sites.
• Acetaldehyde was also highest in the summer for TSOK and TUOK.
• Xylenes were significantly higher during the summer for TSOK.
20.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for the Oklahoma monitoring sites was
evaluated using ATSDR short-term (acute) and intermediate MRL and California EPA acute
REL factors. Acute risk is defined as exposures from 1 to 14 days while intermediate risk is
defined as exposures from 15 to 364 days. It is useful to compare the preprocessed daily
measurements to the short-term MRL and REL factors, as well as compare seasonal averages to
the intermediate MRL. Of the pollutants with at least one failed screen, only acrolein exceeded
20-12
-------
Table 20-3. Daily and Seasonal Averages for the Pollutants of Interest for the Oklahoma Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Hg/m3)
Conf.
Int.
Autumn
Avg
(Hg/m3)
Conf.
Int.
Cherokee Nation, Oklahoma - CNEP
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
14
14
10
14
14
14
14
14
2.06
0.58
0.04
0.76
0.74
0.09
0.01
0.07
NR
NR
NR
NR
NR
NR
NR
NR
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
2.11
0.60
0.03
0.80
0.92
0.10
0.01
0.07
Tulsa, Oklahoma - Site 1 - TOOK
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Manganese (TSP)
Nickel (TSP)
Tetrachloroethylene
Xylenes
44
44
14
44
38
44
44
44
14
14
34
44
44
44
14
44
44
44
44
44
14
14
44
44
2.03
0.94
0.01
2.35
0.09
0.59
0.20
3.72
0.03
0.01
0.24
5.38
0.27
0.18
0.01
0.43
0.02
0.05
0.03
0.60
0.01
0.01
0.06
1.09
1.44
0.51
NR
2.41
0.10
0.48
0.21
1.63
NR
NR
NR
5.38
0.54
0.14
NR
1.02
0.04
0.10
0.13
0.46
NR
NR
NR
2.64
1.75
1.25
NA
1.92
NR
0.49
0.25
3.33
NA
NA
NR
5.22
0.44
0.31
NA
0.89
NR
0.07
0.05
0.91
NA
NA
NR
2.10
2.49
1.12
NA
2.27
0.06
0.72
0.21
5.79
NA
NA
0.22
5.55
0.48
0.47
NA
0.59
0.02
0.09
0.03
0.85
NA
NA
0.11
1.70
2.11
0.80
0.01
2.73
0.08
0.63
0.14
3.01
0.03
0.01
0.21
5.33
0.50
0.18
0.01
0.94
0.03
0.07
0.04
0.64
0.01
0.01
0.07
2.36
Tulsa, Oklahoma - Site 2 - TSOK
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Manganese (TSP)
28
29
15
29
28
28
29
28
15
28
29
15
29
29
29
29
28
15
1.88
1.35
0.01
1.21
0.08
0.67
0.16
4.24
0.02
0.29
0.38
0.01
0.32
0.02
0.07
0.05
0.88
0.01
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
2.36
1.44
NA
1.33
0.06
0.73
0.24
6.25
NA
0.46
0.38
NA
0.65
0.02
0.08
0.10
1.08
NA
1.61
1.61
0.01
1.20
0.09
0.69
0.12
3.27
0.03
0.25
0.83
0.01
0.30
0.02
0.07
0.03
0.70
0.01
to
o
-------
Table 20-3. Daily and Seasonal Averages for the Pollutants of Interest for the Oklahoma Monitoring Sites (Continued)
Pollutant
Tetrachloroethylene
Xylenes
#of
Measured
Detections
27
29
#of
Samples
29
29
Daily
Avg
(Hg/m3)
0.17
9.18
Conf.
Int.
0.04
3.19
Winter
Avg
(Hg/m3)
NR
NR
Conf.
Int.
NR
NR
Spring
Avg
(Hg/m3)
NA
NA
Conf.
Int.
NA
NA
Summer
Avg
(Ug/m3)
0.14
14.66
Conf.
Int.
0.04
5.57
Autumn
Avg
(Ug/m3)
0.20
5.83
Conf.
Int.
0.09
1.85
Tulsa, Oklahoma - Site 3 - TUOK
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Manganese (TSP)
Tetrachloroethylene
30
31
13
31
31
31
31
30
13
29
30
31
13
31
31
31
31
30
13
31
2.67
0.92
<0.01
1.40
0.09
0.65
0.16
4.10
0.02
0.64
0.40
0.19
<0.01
0.29
0.02
0.06
0.06
0.68
0.01
0.25
2.02
0.87
NR
1.81
0.13
0.48
0.23
2.09
NR
NR
1.13
0.49
NR
0.90
0.07
0.11
0.22
0.75
NR
NR
NR
NR
NA
NR
NR
NR
NR
NR
NA
NR
NR
NR
NA
NR
NR
NR
NR
NR
NA
NR
3.30
0.96
NA
1.39
0.08
0.72
0.18
5.74
NA
0.45
0.47
0.25
NA
0.26
0.02
0.08
0.04
0.82
NA
0.19
2.39
0.90
<0.01
1.13
0.07
0.69
0.11
3.59
0.02
0.93
0.37
0.26
<0.01
0.29
0.02
0.09
0.04
0.61
0.01
0.58
to
o
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
-------
either the acute and intermediate risk values, and each site's non-chronic risk is summarized in
Table 20-4.
The following observations about acrolein are shown in Table 20-4:
• All of the acrolein measured detections at the Oklahoma sites were greater than the
ATSDR acute value of 0.11 |ig/m3 and all but two were greater than the California
REL value of 0.19 |ig/m3.
3
• The average detected concentration of acrolein was 2.06 ± 0.74 jig/m for CNEP; 0.94
±0.18).
TUOK.
±0.18 |ig/m3for TOOK; 1.35 ± 0.38 |ig/m3for TSOK; and 0.92 ±0.19 |ig/m3for
• CNEP and TSOK's acrolein averages were an order of magnitude higher than either
acute risk factor.
• Only some of the seasonal averages for acrolein could be calculated, therefore
intermediate risk could not be evaluated in several cases. But where seasonal
averages could be calculated, the intermediate risk factor was exceeded.
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of
concentration and wind direction. Only acrolein concentrations exceeded the acute risk factors.
Figures 20-7 through 20-10 are pollution roses for acrolein at the CNEP, TOOK, TSOK, and
TUOK sites, respectively. As shown in Figures 20-7 and 20-10, all acrolein concentrations
exceeded the ATSDR acute risk factor, which is indicated by a solid line, and all except one
acrolein concentration at CNEP and one at TUOK exceeded the CALEPA REL, which is
indicated by a dashed line.
Observations gleaned from the acrolein pollution roses include:
• High concentrations of acrolein were measured on days with winds from a variety of
directions.
• No acrolein measured detections at CNEP occurred with southeasterly, westerly or
northwesterly winds.
• The TOOK pollution rose shows a more random scattering of concentrations,
although more frequently measured with southerly winds. The highest concentration
was measured on a day with northeasterly winds.
20-15
-------
Table 20-4. Non-Chronic Risk Summary for the Oklahoma Monitoring Sites
Site
CNEP
TOOK
TSOK
TUOK
Method
TO- 15
TO- 15
TO- 15
TO- 15
Pollutant
Acrolein
Acrolein
Acrolein
Acrolein
Daily
Average
(ug/m3)
2.06 ± 0.74
0.94 ±0.18
1.35 ±0.38
0.92 ±0.19
ATSDR
Short-term
MRL (ug/m3)
0.11
0.11
0.11
0.11
# of ATSDR
MRL
Exceedances
14
44
29
31
CAL EPA
REL
Acute
(ug/m3)
0.19
0.19
0.19
0.19
# of CAL
EPA REL
Exceedances
13
44
29
30
ATSDR
Intermediate-
term MRL
(ug/m3)
0.09
0.09
0.09
0.09
Winter
Average
(ug/m3)
NA
0.51
±0.14
NR
0.87±
0.49
Spring
Average
(ug/m3)
NA
1.25
±0.31
NA
NR
Summer
Average
(Ug/m3)
NA
1.12
±0.47
1.44
±0.38
0.96
±0.25
Autumn
Average
(Ug/m3)
2.11
±0.92
0.80
±0.18
1.61
±0.83
0.90
±0.26
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
to
o
-------
Figure 20-7. Acrolein Pollution Rose for CNEP
to
o
CAEPAREL(0.19|jg/m
ATSDRMRL(0.11 |jg/m
Daily Avq Cone =2.06 ± 0.74 uq/m
3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
Pollutant Concentration
-------
Figure 20-8. Acrolein Pollution Rose for TOOK
to
-------
Figure 20-9. Acrolein Pollution Rose for TSOK
to
o
\D
4.5
4.0
3.5
3.0
2.5
2.0
1.5
£ 1.0
IE
c 0.5
o 0.0
O
1.5
2.0
2.5
3.0
3.5
4.0
4.5
NW
w
sw
*--,
— CA EPA REL (0. 1 9 |jg/m3
— ATSDRMRL(0.11 |jg/m3
**
Daily Avq Cone =1.35 ±0.38 uq/m3
NE
SE
___________________^
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
Pollutant Concentration
-------
Figure 20-10. Acrolein Pollution Rose for TUOK
to
o
to
o
CAEPAREL(0.19ug/m
ATSDRMRL(0.11 ug/m
3.5
3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0
Pollutant Concentration
Daily Avg Cone =0.92 ±0.19 ug/m
1.5 2.0 2.5 3.0 3.5
4.0
-------
• The TSOK pollution rose shows that acrolein was detected mostly on days with
winds from the north and south, while the highest concentration detected was
measured on a day with a northwesterly wind.
• The TUOK pollution rose shows a northeast/southwest wind pattern similar to that of
CNEP, while the highest concentration was measured on a day with winds from the
west.
20.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
20.4.1 Pearson Correlation Analysis
Table 20-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the Oklahoma monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for CNEP from Table 20-5:
• The correlations calculated for the pollutants of interest were weak.
• A correlation for sea level pressure could not be calculated because this parameter
was not recorded at this station.
The following observations are gathered for TOOK from Table 20-5:
• Formaldehyde and carbon tetrachloride exhibited strong positive correlations with
maximum, average, dew point, and wet bulb temperatures. This indicates that
concentrations of these pollutants increase as temperature and moisture content
increase.
• Arsenic and acetaldehyde also exhibited strong positive correlations with maximum
temperatures, indicating that concentrations of these pollutants increase as
temperatures increase.
• Several pollutants exhibited strong negative correlations with the scalar wind speed,
and all of the correlations with this variable were negative. This indicates the
concentrations increase as wind speeds decrease.
20-21
-------
Table 20-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Oklahoma Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea
Level
Pressure
Scalar
Wind
Speed
Cherokee Nation, Oklahoma - CNEP
1,3 -Butadiene
Acrolein
Benzene
Carbon Tetrachloride
10
14
14
14
-0.29
0.20
-0.35
0.46
-0.23
0.25
-0.32
0.43
0.02
0.17
-0.11
0.43
-0.09
0.20
-0.20
0.44
0.43
-0.10
0.33
0.24
NA
NA
NA
NA
-0.34
-0.31
-0.39
0.23
Tulsa, Oklahoma - Site #1 - TOOK
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
Carbon Tetrachloride
Formaldehyde
Manganese (TSP)
Nickel (TSP)
£>-Dichlorobenzene
Tetrachloroethylene
Xylenes
38
44
44
14
44
44
44
14
14
44
34
44
-0.29
0.58
0.33
0.58
0.11
0.54
0.82
0.36
0.24
0.21
0.15
0.22
-0.43
0.46
0.37
0.42
-0.04
0.50
0.80
0.13
0.24
0.16
0.10
0.10
-0.46
0.33
0.46
0.45
-0.07
0.49
0.70
-0.02
0.37
0.12
0.02
0.04
-0.45
0.38
0.43
0.43
-0.06
0.51
0.74
0.04
0.32
0.15
0.06
0.06
-0.07
-0.32
0.26
0.29
-0.01
-0.06
-0.33
-0.24
0.45
-0.15
-0.17
-0.13
0.15
-0.22
-0.18
-0.05
-0.03
-0.25
-0.34
0.17
-0.06
-0.40
-0.11
-0.19
-0.50
-0.37
-0.07
-0.60
-0.51
-0.06
-0.01
-0.58
-0.20
-0.12
-0.12
-0.44
Tulsa, Oklahoma - Site #2 - TSOK
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
Carbon Tetrachloride
28
28
29
15
29
28
-0.29
0.57
0.14
0.33
0.06
0.69
-0.36
0.57
0.14
0.22
0.08
0.65
-0.40
0.42
0.15
0.22
0.15
0.59
-0.38
0.48
0.15
0.21
0.13
0.63
-0.09
-0.44
0.01
0.05
0.24
-0.28
0.42
-0.25
0.03
0.15
-0.07
-0.39
-0.45
-0.23
0.05
-0.50
-0.47
0.08
to
o
to
to
-------
Table 20-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Oklahoma Monitoring Sites (Continued)
Pollutant
Formaldehyde
Manganese (TSP)
p-Dichlorobenzene
Tetrachloroethylene
Xylenes
#of
Measured
Detections
28
15
29
27
29
Maximum
Temperature
0.82
0.26
0.44
-0.11
0.46
Average
Temperature
0.82
0.19
0.40
-0.16
0.49
Dew Point
Temperature
0.70
-0.05
0.44
-0.18
0.59
Wet Bulb
Temperature
0.75
0.08
0.43
-0.17
0.56
Relative
Humidity
-0.42
-0.48
0.07
-0.01
0.23
Sea
Level
Pressure
-0.44
0.31
-0.14
-0.03
-0.29
Scalar
Wind
Speed
-0.05
-0.54
-0.24
-0.19
-0.30
Tulsa, Oklahoma - Site #3 - TUOK
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (TSP)
Benzene
Carbon Tetrachloride
Formaldehyde
Manganese (TSP)
£>-Dichlorobenzene
Tetrachloroethylene
31
30
31
13
31
31
30
13
31
29
-0.35
0.55
0.22
-0.29
-0.13
0.65
0.83
-0.14
0.03
0.14
-0.40
0.47
0.18
-0.43
-0.17
0.64
0.79
-0.23
-0.01
0.05
-0.37
0.40
0.17
-0.24
-0.15
0.60
0.71
-0.39
-0.04
-0.02
-0.39
0.41
0.18
-0.37
-0.17
0.62
0.74
-0.27
-0.03
0.00
0.18
-0.26
0.00
0.35
0.10
-0.19
-0.39
-0.46
-0.11
-0.17
0.41
-0.17
-0.34
0.08
0.04
-0.55
-0.38
0.62
-0.21
-0.21
-0.42
-0.45
-0.29
-0.41
-0.41
-0.04
-0.19
0.04
-0.30
-0.11
to
o
to
oo
NA = Not available due to short sampling duration.
-------
The following observations are gathered for TSOK from Table 20-5:
• Similar to TOOK, formaldehyde and carbon tetrachloride exhibited strong positive
correlations with maximum, average, dew point, and wet bulb temperatures. This
indicates that concentrations of these pollutants increase as temperature and moisture
content increase.
• Acetaldehyde exhibited strong positive correlations with maximum and average
temperatures, indicating that concentrations of this pollutant increase as temperatures
increase.
• Xylenes exhibited strong positive correlations with dew point and wet bulb
temperatures, which indicates the increasing moisture content leads to increasing
concentrations of xylenes.
• Most of the correlations with scalar wind speed were negative. This indicates the
concentrations increase as wind speeds decrease.
The following observations are gathered for TUOK from Table 20-5:
• Similar to TOOK and TSOK, formaldehyde and carbon tetrachloride exhibited strong
positive correlations with maximum, average, dew point, and wet bulb temperatures.
This indicates that concentrations of these pollutants increase as temperature and
moisture content increase.
• Like TOOK, acetaldehyde exhibited a strong positive correlation with maximum
temperature, indicating that concentrations of this pollutant increase as temperatures
increase.
• Carbon tetrachloride and manganese exhibited strong correlations with sea level
pressure, which indicates changes in pressure lead to changes in concentrations of the
pollutants.
• Most of the correlations with scalar wind speed were negative. This indicates the
concentrations increase as wind speeds decrease.
20.4.2 Composite Back Trajectory Analysis
Figures 20-11 through 20-14 are composite back trajectory maps for the Oklahoma
monitoring sites for the days on which sampling occurred. Each line represents the 24-hour
trajectory along which a parcel of air traveled toward the monitoring site on a sampling day.
Each concentric circle around the site represents 100 miles.
20-24
-------
Figure 20-11. Composite Back Trajectory Map for CNEP
9
to
-------
Figure 20-12. Composite Back Trajectory Map for TOOK
9
8
-------
Figure 20-13. Composite Back Trajectory Map for TSOK
-------
Figure 20-14. Composite Back Trajectory Map for TUOK
-------
The following observations can be made from Figure 20-11 for CNEP:
• Back trajectories originated predominantly from the north and south at CNEP.
• The 24-hour airshed domain was large, with trajectories originating as far away as
North Dakota (~ 800 miles).
• Over 50 percent of the trajectories originated within 300 miles of the site and 75
percent within 400 miles from CNEP.
• The composite back trajectory map might look much different with a full year's
worth of sampling days.
The following observations can be made for the Tulsa sites from Figures 20-12 through
20-14:
• Back trajectories for the Tulsa sites originated predominately from the north and
south, similar to CNEP.
• The longest trajectories originated nearly 900 miles to the north of the sites,
indicating that the 24-hour airshed domain was large for Tulsa.
• The majority of the back trajectories originated with 400 miles from the sites.
20.4.3 Wind Rose Analysis
Hourly wind data from the Claremore Regional Airport, Richard Lloyd Jones, Jr. Airport,
and Tulsa International Airport weather station were uploaded into a wind rose software
program, WRPLOT (Lakes, 2006). WRPLOT produces a graphical wind rose from the wind
data. A wind rose shows the frequency of wind directions about a 16-point compass, and uses
different shading to represent wind speeds. Figures 20-15 through 20-18 present the wind roses
for the Oklahoma monitoring sites on days that sampling occurred.
Observations from Figures 20-15 through 20-18 include:
• Hourly winds near the Oklahoma sites were predominantly out of the south (over 20
percent of observations for each site).
• The frequency of calm winds (<2 knots) varied by site, ranging from 10 percent near
TSOK to 27 percent near TOOK.
20-29
-------
Figure 20-15. Wind Rose for CNEP Sampling Days
NORTH"---.
•WEST
to
o
25%
'X 20%
15%
1 0%
SOUTH .---
EAST
WIND SPEED
(Knots)
I | >=22
• 17 - 21
^| -1-1 - -17
2- 4
Calms: 17.80%
-------
Figure 20-16. Wind Rose for TOOK Sampling Days
WEST
to
o
NORTH"--*.
30%
18%
1 2%
•SOUTH --'
I EAST
WIND SPEED
(Knots)
I | >=22
I I 17 - 21
• 11 - 17
^| 7- 11
I I 4- 7
^| 2- 4
Calms: 26.92%
-------
Figure 20-17. Wind Rose for TSOK Sampling Days
NORTH"--
30%
~ ~~ ~~ -. ^ ^
*""„ 24%
"" ••, 18%
12%
6%
WEST
! EAST
to
o
to
'SOUTH, --
WIND SPEED
(Knots)
17 - 21
^| 11 - 17
^| 7- 11
^| 2- 4
Calm;: 9.53%
-------
Figure 20-18. Wind Rose for TUOK Sampling Days
to
o
•SOUTH .-'
WIND SPEED
(Knots)
| | *= 22
I I 17 - 21
• 11 - 17
^| 7- 11
I I ^l- 7
^| 2- 4
Calms: 26.05%
-------
20.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as these sites did not sample for SNMOC.
20.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Tulsa and Chippewa Counties were
obtained from the Oklahoma Tax Commission and the U.S. Census Bureau, and are summarized
in Table 20-6. Table 20-6 also includes a vehicle registration to county population ratio
(vehicles per person). In addition, the population within 10 miles of each site is presented. An
estimation of 10-mile vehicle registration was computed using the 10-mile population
surrounding the monitor and the vehicle registration ratio. Finally, Table 20-6 contains the
average daily traffic information, which represents the average number of vehicles passing the
monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 20-6 include:
• The population and vehicle registration near the Tulsa sites is significantly higher
than the CNEP site.
• Of the three Tulsa sites, TUOK has the highest 10 mile population and vehicle
ownership, although the TOOK population and vehicle ownership data is very
similar.
• TUOK and TSOK experience a significantly higher traffic volume than the TOOK
site.
• Compared to other UATMP sites, TOOK, TSOK, and TUOK's population and
vehicle ownership is in the middle of the range.
• TSOK and TUOK's daily traffic volume is in the top 10 highest traffic volumes of all
UATMP sites.
• CNEP has one of the lowest county population and vehicle registrations compared to
other sites.
• The traffic volume for CNEP is the lowest recorded for all UATMP sites. TOOK
also has a relatively low daily traffic volume.
20-34
-------
Table 20-6. Motor Vehicle Information for the Oklahoma Monitoring Sites
Site
CNEP
TOOK
TSOK
TUOK
2006 Estimated
County Population
39,774
577,795
577,795
577,795
Number of
Vehicles
Registered
29,815
498,898
498,898
498,898
Vehicles per Person
(Registration:
Population)
0.75
0.86
0.86
0.86
Population Within
10 Miles
31,107
459,346
377,360
460,577
Estimated 10 Mile
Vehicle Ownership
23,318
396,623
291,294
397,686
Traffic Data
(Daily Average)
5
500
62,500
82,600
to
o
-------
20.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compares them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• Of the Oklahoma sites, TSOK's ratios most resemble the ratios of the roadside study.
• TSOK had the lowest ratios of the Oklahoma sites.
• For CNEP, the benzene-ethylbenzene ratio was the highest of the three ratios; for the
three Tulsa sites, toluene-ethylbenzene ratios were the highest, similar to the roadside
study.
• For TOOK, all three ratios were higher than those in the roadside study, with
TOOK's toluene-ethylbenzene ratio being significantly higher than the roadside
study. A similar trend is shown for TUOK.
• For both TOOK and TUOK, the benzene-ethylbenzene ratio was higher than the
xylenes-ethylbenzene ratio.
20.6 Trends Analysis
A trends analysis could not be performed because the Oklahoma sites have not
participated in the UATMP for three consecutive years.
20.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Oklahoma sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 20-7.
Additionally, the pollutants of interest are bolded. CNEP and TSOK did not collect enough
samples for annual averages for the pollutants of interest to be calculated. Similarly, the Tulsa
sites did not begin sampling metals until October, so annual averages for metals could not be
20-36
-------
Table 20-7. Chronic Risk Summary for the Monitoring Sites in Oklahoma
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Ug/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(Ug/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Cherokee Nation, Pryor, Oklahoma (CNEP) - Census Tract ID 40097040400
Acrolein
Benzene
1,3-Butadiene
Carbon Tetrachloride
1 ,2-Dichloroethane
NR
0.0000078
0.00003
0.000015
0.000026
0.00002
0.03
0.002
0.04
2.4
0.02
0.43
0.01
0.21
0.01
NR
3.36
0.30
3.20
0.32
0.95
0.01
0.01
0.01
0.01
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Site #1, Tulsa, Oklahoma (TOOK) - Census Tract ID 40143004600
Acetaldehyde
Acrolein
Acrylonitrile
Arsenic*
Benzene
1,3-Butadiene
Cadmium*
Carbon Tetrachloride
Chloromethane
p-Dichlorobenzene
1 ,2-Dichloroethane
Dichloromethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese*
Nickel*
Tetrachloroethylene
Xylenes
0.0000022
NR
0.000068
0.0043
0.0000078
0.00003
0.0018
0.000015
NR
0.000011
0.000026
0.00000047
5.5E-09
0.000022
NR
0.00016
0.0000059
NR
0.009
0.00002
0.002
0.00003
0.03
0.002
0.00002
0.04
0.09
0.8
2.4
1
0.0098
0.09
0.00005
0.000065
0.27
0.1
1.91
0.13
O.01
0.01
3.89
0.24
0.01
0.21
0.95
0.03
0.03
0.33
1.74
0.01
0.01
O.01
0.17
6.76
4.20
NR
0.02
0.13
30.35
7.35
0.15
3.21
NR
0.36
0.87
0.15
0.01
0.03
NR
0.44
1.00
NR
0.21
6.59
O.01
0.01
0.13
0.12
0.01
0.01
0.01
0.01
O.01
0.01
0.18
0.01
0.03
0.04
0.01
0.07
2.03 ±0.27
0.94 ±0.18
0.07 ± 0.02
NA
2.35 ±0.43
0.08 ±0.02
NA
0.59 ±0.05
1.36 ±0.39
0.20 ±0.03
0.03 ± O.01
0.46 ± 0.27
3.72 ±0.60
0.07 ±0.01
NA
NA
0.20 ±0.05
5. 38 ±1.09
4.46
NR
4.78
NA
18.30
2.32
NA
8.86
NR
2.19
0.82
0.22
0.02
1.62
NA
NA
1.15
NR
0.23
46.90
0.04
NA
0.08
0.04
NA
0.01
0.02
0.01
O.01
0.01
0.38
0.01
NA
NA
0.01
0.05
Site #2, Tulsa, Oklahoma (TSOK) - Census Tract ID 40143000900
Acetaldehyde
Acrolein
Acrylonitrile
0.0000022
NR
0.000068
0.009
0.00002
0.002
1.74
0.11
0.01
3.83
NR
0.02
0.19
5.73
0.01
NA
NA
NA
NA
NA
NA
NA
NA
NA
to
o
-------
Table 20-7. Chronic Risk Summary for the Monitoring Sites in Oklahoma (Continued)
Pollutant
Arsenic*
Benzene
1,3-Butadiene
Cadmium*
Carbon Tetrachloride
p-Dichlorobenzene
Formaldehyde
Manganese*
Nickel*
Tetrachloroethylene
Xylenes
Cancer
URE
Oig/m3)
0.0043
0.0000078
0.00003
0.0018
0.000015
0.000011
5.5E-09
NR
0.00016
0.0000059
NR
Noncancer
RfC
Oig/m3)
0.00003
0.03
0.002
0.00002
0.04
0.8
0.0098
0.00005
0.000065
0.27
0.1
1999 NATA
Modeled
Concentration
(Ug/m3)
0.01
1.93
0.18
0.01
0.21
0.04
1.51
O.01
0.01
0.23
2.88
Cancer Risk
(in-a-
million)
0.08
15.09
5.33
0.09
3.18
0.41
0.01
NR
0.20
1.33
NR
Noncancer
Risk (HQ)
0.01
0.06
0.09
0.01
0.01
0.01
0.15
0.02
0.02
O.01
0.03
2006 UATMP
Annual
Average
(Ug/m3)
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Cancer
Risk (in-a-
million)
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Noncancer
Risk (HQ)
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Site #3, Tulsa, Oklahoma (TUOK) - Census Tract ID 40143003200
Acetaldehyde
Acrolein
Acrylonitrile
Arsenic*
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese*
Nickel*
Tetrachloroethylene
Xylenes
0.0000022
NR
0.000068
0.0043
0.0000078
0.00003
0.000015
0.000011
0.000026
5.5E-09
0.000022
NR
0.00016
0.0000059
NR
0.009
0.00002
0.002
0.00003
0.03
0.002
0.04
0.8
2.4
0.0098
0.09
0.00005
0.000065
0.27
0.1
1.59
0.11
O.01
0.01
1.79
0.18
0.21
0.03
0.03
1.47
O.01
0.01
O.01
0.21
2.79
3.51
NR
0.02
0.08
13.95
5.28
3.14
0.32
0.85
0.01
0.03
NR
0.19
1.27
NR
0.18
5.44
O.01
0.01
0.06
0.09
0.01
O.01
0.01
0.15
O.01
0.02
0.02
0.01
0.03
2.67 ±0.4
0.92 ±0.19
0.06 ±0.01
NA
1.4 ±0.29
0.09 ±0.02
0.65 ±0.06
0.16 ±0.06
0.03 ±0.01
4.1 ±0.68
0.08 ±0.01
NA
NA
0.6 ±0.24
4.14 ±1.32
5.87
NR
4.40
NA
10.95
2.75
9.73
1.81
0.8
0.02
1.65
NA
NA
3.55
NR
0.30
45.86
0.03
NA
0.05
0.05
0.02
O.01
0.01
0.42
O.01
NA
NA
0.01
0.04
* Metals sampled with TSP filters NR = a risk factor is not available and therefore, no risk calculation can be made.
BOLD indicates a pollutant of interest NA = annual average not available
to
o
oo
-------
calculated. In addition to the annual averages and risks based on 2006 monitoring data, where
available, data from EPA's 1999 NATA were retrieved and are also presented in Table 20-7.
The NATA data are presented for the census tract where the monitoring site is located.
The census tract information for the Oklahoma sites is as follows:
• The census tract for CNEP is 40097040400, which had a population of 5,307 and
represents approximately 14 percent of the Mayes County population in 2000.
• The census tract for TOOK is 40143004600, which had a population of 3,147 and
represents approximately 0.6 percent of the Tulsa County population in 2000.
• The census tract for TSOK is 40143000900, which had a population of 1,590 and
represents approximately 0.3 percent of the Tulsa County population in 2000.
• The census tract for TUOK is 40143003200, which had a population of 1,677, and
represents approximately 0.3 percent of the Tulsa County population in 2000.
The following observations can be made for CNEP from Table 20-7:
• Benzene had the highest NATA-modeled concentration of all the pollutants of
interest for CNEP.
• The NATA-modeled cancer risks for benzene and carbon tetrachloride were both
greater than 1 in-a-million (3.36 and 3.20 in-a-million, respectively).
• None of the NATA-modeled noncancer risks were greater than 1.0.
• Acrolein's noncancer risk was the highest (0.95).
The following observations can be made for the Tulsa sites from Table 20-7:
• Xylenes and formaldehyde had the highest annual averages for TOOK and TUOK,
while xylenes and benzene had the highest NATA-modeled concentrations for all
three Tulsa sites.
• Benzene and carbon tetrachloride had the highest cancer risks based on annual
average for TOOK and TUOK.
• Benzene and 1,3-butadiene had the highest cancer risks for the Tulsa sites according
to NATA.
20-39
-------
• Like most sites, acrolein was the only pollutant with a noncancer HQ greater than 1,
although the annual average based risk is significantly higher than the NATA
modeled risk.
20.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 20-8 and 20-9 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 20-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 20-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. In addition, the highest cancer and noncancer risks based on the annual
average are limited to those pollutants failing at least one screen.
The following observations for CNEP can be made from Table 20-8:
• Benzene was the highest emitted pollutant with cancer risk factor in Mayes County,
Oklahoma and had the third highest toxicity-weighted emissions.
• Arsenic and hexavalent chromium had the highest toxicity-weighted emissions in
Mayes County.
• Annual averages could not be calculated for CNEP, so no cancer risk calculations
could be made.
The following observations for the Tulsa sites can be made from Table 20-8:
• In Tulsa County, benzene had both the highest emissions and the highest toxicity-
weighted emissions, which is similar to most UATMP counties.
• Benzene also had the highest cancer risk based on annual averages for TOOK and
TUOK.
20-40
-------
Table 20-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Oklahoma
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on
Annual Average Concentration
(Site-Specific)
Pollutant
Cancer
Risk
(in-a-
million)
Cherokee Nation, Oklahoma (CNEP) - Mayes County
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Naphthalene
Dichloromethane
Polycyclic Organic Matter as 7-PAH
Trichloroethylene
Benzyl Chloride
Tetrachloroethylene
70.47
59.29
10.22
5.69
5.36
3.47
2.17
1.86
1.40
1.24
Arsenic
Hexavalent Chromium
Benzene
Cadmium
Naphthalene
1,3 -Butadiene
Polycyclic Organic Matter as 7-PAH
Lead
Nickel
Benzyl Chloride
3.87E-03
7.45E-04
5.50E-04
.94E-04
.82E-04
.71E-04
.53E-04
.07E-04
9.65E-05
6.86E-05
Tulsa, Oklahoma, Site #1 (TOOK) - Tulsa County
Benzene
Formaldehyde
Tetrachloroethylene
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Trichloroethylene
Naphthalene
£>-Dichlorobenzene
Polycyclic Organic Matter as 15 -PAH
656.52
230.68
95.57
81.21
74.76
24.20
22.32
19.63
12.22
3.33
Benzene
Lead
1,3 -Butadiene
Hexavalent Chromium
Naphthalene
Tetrachloroethylene
Polycyclic Organic Matter as 15 -PAH
Acetaldehyde
Polycyclic Organic Matter as 7-PAH
/>-Dichlorobenzene
5.12E-03
2.71E-03
2.24E-03
1.45E-03
6.67E-04
5.64E-04
1.83E-04
1.79E-04
1.68E-04
1.34E-04
Benzene
Carbon Tetrachloride
Acrylonitrile
Acetaldehyde
1,3 -Butadiene
£>-Dichlorobenzene
Hexachloro- 1 , 3 -butadiene
Tetrachloroethylene
1 ,2-Dichloroethane
Dichloromethane
18.30
8.86
4.78
4.46
2.32
2.19
1.62
1.15
0.82
0.22
to
o
-------
Table 20-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Oklahoma (Continued)
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Tulsa, Oklahoma, Site #2 - (TSOK) - Tulsa County
Benzene
Formaldehyde
Tetrachloroethylene
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Trichloroethylene
Naphthalene
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15 -PAH
656.52
230.68
95.57
81.21
74.76
24.20
22.32
19.63
12.22
3.33
Benzene
Lead
1,3 -Butadiene
Hexavalent Chromium
Naphthalene
Tetrachloroethylene
Poly cyclic Organic Matter as 15-PAH
Acetaldehyde
Polycyclic Organic Matter as 7-PAH
/>-Dichlorobenzene
5.12E-03
2.71E-03
2.24E-03
1.45E-03
6.67E-04
5.64E-04
1.83E-04
1.79E-04
1.68E-04
1.34E-04
Tulsa, Oklahoma, Site #3 (TUOK) - Tulsa County
Benzene
Formaldehyde
Tetrachloroethylene
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Trichloroethylene
Naphthalene
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15-PAH
656.52
230.68
95.57
81.21
74.76
24.20
22.32
19.63
12.22
3.33
Benzene
Lead
1,3 -Butadiene
Hexavalent Chromium
Naphthalene
Tetrachloroethylene
Polycyclic Organic Matter as 15-PAH
Acetaldehyde
Polycyclic Organic Matter as 7-PAH
/>-Dichlorobenzene
5.12E-03
2.71E-03
2.24E-03
1.45E-03
6.67E-04
5.64E-04
1.83E-04
1.79E-04
1.68E-04
1.34E-04
Benzene
Carbon Tetrachloride
Acetaldehyde
Acrylonitrile
Tetrachloroethylene
1,3 -Butadiene
£>-Dichlorobenzene
Hexachloro- 1 ,3 -butadiene
1 ,2-Dichloroethane
Formaldehyde
10.95
9.73
5.87
4.40
3.55
2.75
1.81
1.65
0.80
0.02
to
o
to
-------
Table 20-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Oklahoma
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk
(HQ)
Cherokee Nation, Oklahoma (CNEP) - Mayes County
Toluene
Xylenes
Benzene
Hydrochloric Acid
Formaldehyde
Methanol
Ethylene Glycol
Methyl Ethyl Ketone
Hexane
Ethylbenzene
140.89
91.15
70.47
61.46
59.29
58.86
25.78
24.77
22.47
21.85
Acrolein
Arsenic
Manganese
Nickel
Formaldehyde
Cadmium
Cyanide
Hydrochloric Acid
1,3 -Butadiene
Mercury
88,332.62
30,003.79
20,653.19
9,274.52
6,050.05
5,391.68
3,097.21
3,072.88
2,845.14
2,650.60
Tulsa, Oklahoma, Site #1 (TOOK) - Tulsa County
Toluene
Xylenes
Benzene
Methanol
Hexane
Ethylbenzene
Methyl Ethyl Ketone
Formaldehyde
Methyl Isobutyl Ketone
Tetrachloroethylene
1,693.16
1,071.67
656.52
315.45
285.46
259.65
237.23
230.68
132.45
95.57
Acrolein
Manganese
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Nickel
Acetaldehyde
Cyanide
Naphthalene
666,521.43
44,619.69
37,378.71
23,538.94
21,883.97
10,716.70
10,459.51
9,023.31
7,120.19
6,543.01
Acrolein
Formaldehyde
Acetaldehyde
Benzene
Xylenes
1,3 -Butadiene
Acrylonitrile
Chloromethane
Carbon Tetrachloride
Hexachloro- 1 ,3 -butadiene
46.90
0.38
0.23
0.08
0.05
0.04
0.04
0.02
0.01
0.01
to
o
-------
Table 20-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Oklahoma (Continued)
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Tulsa, Oklahoma, Site #2 (TSOK) - Tulsa County
Toluene
Xylenes
Benzene
Methanol
Hexane
Ethylbenzene
Methyl Ethyl Ketone
Formaldehyde
Methyl Isobutyl Ketone
Tetrachloroethylene
1,693.16
1,071.67
656.52
315.45
285.46
259.65
237.23
230.68
132.45
95.57
Acrolein
Manganese
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Nickel
Acetaldehyde
Cyanide
Naphthalene
666,521.43
44,619.69
37,378.71
23,538.94
21,883.97
10,716.70
10,459.51
9,023.31
7,120.19
6,543.01
Tulsa, Oklahoma, Site #3 (TUOK) - Tulsa County
Toluene
Xylenes
Benzene
Methanol
Hexane
Ethylbenzene
Methyl Ethyl Ketone
Formaldehyde
Methyl Isobutyl Ketone
Tetrachloroethylene
1,693.16
1,071.67
656.52
315.45
285.46
259.65
237.23
230.68
132.45
95.57
Acrolein
Manganese
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Nickel
Acetaldehyde
Cyanide
Naphthalene
666,521.43
44,619.69
37,378.71
23,538.94
21,883.97
10,716.70
10,459.51
9,023.31
7,120.19
6,543.01
Acrolein
Formaldehyde
Acetaldehyde
Benzene
1,3 -Butadiene
Xylenes
Acrylonitrile
Carbon Tetrachloride
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
45.86
0.42
0.30
0.05
0.05
0.04
0.03
0.02
0.01
0.01
to
o
-------
• Lead had the second highest toxicity-weighted emissions.
• Annual averages could not be calculated for TSOK, so no cancer risk calculations
could be made. In addition, annual averages for metals could not be calculated for
the Tulsa sites, so no cancer risk calculations for metals could be made.
The following observations can be made from Table 20-9:
• Like many UATMP counties, toluene and xylenes had the highest emissions in both
Tulsa and Mayes Counties for pollutants with noncancer risk factors.
• Acrolein had the highest toxicity-weighted emissions for both counties, but did not
appear on the list of highest emitted pollutants.
• Acrolein also had the highest noncancer risk for the TOOK and TUOK sites (no
annual average could be calculated for acrolein for TSOK and CNEP).
Oklahoma Pollutant Summary
The pollutants of interest common to all Oklahoma sites were acrolein, benzene, 1,3-
butadiene, and carbon tetrachloride.
Formaldehyde concentrations tended to be higher during the summer at the Tulsa sites.
Acrolein exceeded the short-term risk factors at all four sites.
20-45
-------
21.0 Site in Oregon
This section presents meteorological, concentration, and spatial trends for the UATMP
site in La Grande, Oregon (LAOR). Figure 21-1 is a topographical map showing the monitoring
site in its rural location. Figure 21-2 identifies point source emission locations within 10 miles
of this site that reported to the 2002 NEI for point sources. LAOR is located near a small
number of sources, all of which are located to the west of the site. The sources represent in a
variety of industries, including automotive repair services, fuel combustion processes, and
polymer and resin production.
La Grande is located in a mountain valley in northeast Oregon, between the Wallowa
Mountains to the east and Blue Mountains to the west. The city experiences a somewhat dry
continental climate. The mountains can block storm systems moving across the region that are
still intact after moving across the Cascades (WRCC).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the LAOR monitoring site is at La Grande/Union County Airport (WBAN 24148). Table 21-1
presents the average meteorological conditions of temperature (average maximum and average),
moisture (average dew point temperature, average wet-bulb temperature, and average relative
humidity), pressure (average sea level pressure), and wind information (average scalar wind
speed) for the entire year and on days samples were collected. Also included in Table 21-1 is the
95 percent confidence interval for each parameter. As shown in Table 21-1, average
meteorological conditions on sampling days were much cooler than average weather conditions
throughout the year. This is expected because samples were collected only in January and
February.
21.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the North Carolina
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
21-1
-------
Figure 21-1. La Grande, Oregon (LAOR) Monitoring Site
"R
ft
O N
10" "s
J5
\u>
•?f"
I LA OR ^
\
~-ex ^ "^
3.nt "Ijt
D
36
\fi
XlNitley'
r
\ \
\
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
21-2
-------
Figure 21-2. Facilities Located Within 10 Miles of LAOR
Union
' County
Legend
Note; Due to fadSKy density and collocation, the to^aJ faciliti
displayed may not represent ali facilities wiEhiri the area of i
LAOR UATMP site
10 mile radius
County' boundary
Source Category Group (No. of Facilities)
* Automotive Repair, Services, & Parking (1)
F Fuel Combustion Industrial Facility (1)
a Lumber & Wood Products Facility (1 }
P Miscellaneous Processes Industrial Facility (2)
v Polymers & Resins Production Industrial Facility (1 )
Waste Treatment & Disposal Industrial Facility (1)
21-3
-------
Table 21-1. Average Meteorological Conditions near the Monitoring Site in Oregon
Site
LAOR
WBAN
24148
Average
Type
All
2006
Sampling
Day
Average
Maximum
Temperature
(°F)
61.23
±1.98
41.00
±3.61
Average
Temperature
(»F)
49.76
±1.52
37.23
±3.57
Average
Dew Point
Temperature
(°F)
33.02
±1.04
26.64
±2.07
Average
Wet Bulb
Temperature
(°F)
42.01
±1.12
33.33
±2.53
Average
Relative
Humidity
(%)
57.67
±1.47
66.54
±6.02
Average
Sea Level
Pressure
(mb)
NA1
NA1
Average
Scalar Wind
Speed
(kt)
7.41
±0.44
11.80
±3.80
Sea level pressure was not recorded at the LaGrande/Union County Airport.
to
-------
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. LAOR sampled only hexavalent
chromium. Though detected four times, hexavalent chromium did not fail the screen on any
occasion, as shown in Table 21-2. In order to facilitate analyses, this pollutant will be
considered LAOR's only pollutant of interest.
Table 21-2. Comparison of Measured Concentrations and EPA Screening Values
for the Oregon Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
La Grande, Oregon - LAOR
Hexavalent Chromium
0
4
0
0.00
0.00
21.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 21-3. Annual averages will be presented and discussed in further detail in
later sections.
21-5
-------
Table 21-3. Daily and Seasonal Averages for the Pollutants of Interest for the Oregon Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
La Grande, Oregon - LAOR
Hexavalent Chromium
4
6
0.027
0.025
NR
NR
NA
NA
NA
NA
NA
NA
NR = Not reportable due to low number of measured detections.
NA = Not available due to short sampling duration.
to
-------
The following observations are shown in Table 21-3:
• The daily average for hexavalent chromium for LAOR was 0.027 ± 0.025 ng/m3.
• No winter average could be calculated because of the low number of measured
detections; spring, summer, or autumn averages could not be calculated because this
site stopped sampling in February.
21.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for LAOR was evaluated using ATSDR
short-term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is
defined as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15
to 364 days. Its is useful to compare the preprocessed daily measurement to the short-term MRL
and REL factors, as well as compare the seasonal averages to the intermediate MRL. Hexavalent
chromium did not exceed the ATSDR intermediate MRL. Hexavalent chromium has no acute
risk factors; therefore acute risk could not be assessed.
21.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
21.4.1 Pearson Correlation Analysis
Table 21-4 presents the summary of Pearson correlation coefficients for hexavalent
chromium and select meteorological parameters for the LAOR monitoring site. (Please refer to
Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered from Table 21-4:
• Hexavalent chromium exhibited a strong negative correlation with maximum
temperature, indicating that as temperatures increase, concentrations decrease.
• A strong positive correlation was calculated for relative humidity, indicating that as
relative humidity increases, concentrations of hexavalent chromium decrease.
21-7
-------
Table 21-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Oregon
Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
La Grande, Oregon - LAOR
Hexavalent Chromium
4
-0.54
-0.32
0.36
-0.12
0.74
NA1
-0.31
1 Sea level pressure was not recorded at the LaGrande/Union County Airport.
to
i
oo
-------
• The low number of measured detections likely skewed the correlations.
21.4.2 Composite Back Trajectory Analysis
Figure 21-3 is a composite back trajectory map for the LAOR monitoring site for the
days on which sampling occurred. Each line represents the 24-hour trajectory along which a
parcel of air traveled toward the monitoring site on a sampling day. Each concentric circle
around the site in Figure 21-3 represents 100 miles.
The following observations can be made from Figure 21-3:
• Back trajectories originated from the south and southwest of LAOR.
• The 24-hour airshed domain was smaller at LAOR than most other UATMP sites,
with its furthest trajectory originating 500 miles away, off the California Coast.
• The composite back trajectory for LAOR might look much different with a full year's
worth of sampling day trajectories.
21.4.3 Wind Rose Analysis
Hourly wind data from the La Grande/Union County Airport near the LAOR monitoring
site were uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT
produces a graphical wind rose from the wind data. A wind rose shows the frequency of wind
directions about a 16-point compass, and uses different shading to represent wind speeds.
Figure 21-4 is the wind rose for the LAOR monitoring site on days that sampling occurred.
Observations from Figure 21-4 include:
• Hourly winds were predominantly out of the south (31 percent of observations) and
south-southeast (22 percent) on sampling days.
• Winds tended to be slightly breezier near LAOR than other UATMP sites.
• Wind speeds ranged most frequently from 11 to 17 knots on sampling days (28
percent of observations).
• Calm winds (<2 knots) were recorded for only 6 percent of the observations.
21-9
-------
Figure 21-3. Composite Back Trajectory Map for LA OR
-------
Figure 21-4. Wind Rose for LAOR Sampling Days
WEST!
NORTH"
28%
21%
14%
7%
SOUTH .---•
I EAST
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
• 11 - -17
^| 7- 11
I I A- 7
H 2- 4
Calms: 6.30%
-------
21.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could not
be performed as this site did not sample for VOC. A mobile tracer analysis could not be performed
as this site did not sample for SNMOC.
21.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population information was obtained from the Oregon
Department of Transportation and U.S. Census Bureau, and is summarized in Table 21-5. Table 21-
5 also includes a vehicle registration to county population ratio (vehicles per person). In addition,
the population within 10 miles of each site is presented. An estimate of 10-mile vehicle registration
was computed using the 10-mile population surrounding the monitors and the vehicle registration
ratio. Finally, Table 21-5 contains the average daily traffic information, which represents the
average number of vehicles passing the monitoring sites on the nearest roadway to each site on a
daily basis.
Observations gleaned from Table 21-5 include:
• Compared to other UATMP sites, LAOR's county population, vehicle registration, 10-
mile population and vehicle ownership, and daily traffic volume are in the bottom five for
each statistic.
• LAOR's estimated vehicles per person ratio is the third highest, behind only sites in
Florida and South Dakota.
21.6 Trends Analysis
A trends analysis could not be performed for LAOR as this site has not participated in the
UATMP for three consecutive years.
21.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutant of interest for LAOR. LAOR did not
sample long enough for annual averages to be calculated (refer to Section 3.3.5 regarding the
definition of an annual average), and therefore annual average-based cancer and not cancer risks
21-12
-------
Table 21-5. Motor Vehicle Information for the Oregon Monitoring Site
Site
LAOR
2006 Estimated
County Population
24,345
Number of
Vehicles
Registered
33,263
Vehicles per Person
(Registration:
Population)
1.37
Population Within
10 Miles
15,964
Estimated 10 mile
Vehicle
Ownership
21,812
Traffic Data
(Daily Average)
55
-------
Table 21-6. Chronic Risk Summary for the Monitoring Site in Oregon
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
frig/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
La Grande, Oregon (LAOR) - Census Tract ID 41061970500
Hexavalent Chromium
0.012
0.0001
<0.01
0.09
<0.01
NA
NA
NA
NA = Not available due to short sampling duration.
-------
cannot be assessed. However, data from EPA's 1999 NATA were retrieved and are presented in
Table 21-6. The NATA data are presented for the census tract where the monitoring site is located.
The following observations can be made for LAOR from Table 21-6:
• The census tract for LAOR is 41061970500, which had a population of 3,352 and
represents approximately 13 percent of the Union County population in 2000.
• Cancer and noncancer risk due to hexavalent chromium at LAOR was very low
according to the NATA.
21.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 21-7 and 21-8 present a risk-
based assessment of county-level emissions based on cancer and noncancer toxicity, respectively.
Table 21-7 presents the 10 pollutants with the highest emissions from the 2002 NEI and the 10
pollutants with the highest toxicity-weighted emissions. The 10 pollutants with the highest cancer
risk based on annual averages could not be calculated because there are no annual averages. Table
21-8 presents similar information, but is based on noncancer risk factors. The pollutants in these
tables are limited to those that have cancer and noncancer risk factors, respectively. As a result, the
highest emitted pollutants in the cancer table may not be the same as the noncancer tables, although
the actual value of the emissions will be.
The following observations can be made from Table 21-7:
• Benzene, formaldehyde, and acetaldehyde had the highest emissions (by mass) in Union
County for pollutants with cancer risk factors, but only benzene (which ranked second)
and acetaldehyde (which ranked ninth) were among the top 10 highest cancer toxicity -
weighted emissions.
• POM as non-15 PAH had the highest toxicity-weighted emissions for Union County, but
this pollutant group ranked tenth for total emissions.
The following observations can be made from Table 21-8:
• Like many UATMP counties, toluene and xylenes had the highest emissions in Union
County. However, neither of these pollutants was among those with the top 10 highest
noncancer toxicity-weighted emissions.
21-15
-------
Table 21-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for LAOR
Top 10 Total Emissions for Pollutants with Cancer Risk
Factors
(for Union County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Union County)
Pollutant
Cancer Toxicity
Weight
Top 10 Cancer Risks Based on
Annual Average Concentration
(for LAOR)
Cancer Risk
Pollutant (in-a-million)
La Grande, Oregon - LAOR
Benzene
Formaldehyde
Acetaldehyde
Polycyclic Organic Matter as 7-PAH
Dichloromethane
1,3 -Butadiene
Tetrachloroethylene
Polycyclic Organic Matter as 15 -PAH
Naphthalene
Polycyclic Organic Matter as non-15 PAH
103.09
56.80
17.77
11.30
9.97
6.00
5.99
5.93
4.22
2.83
Polycyclic Organic Matter as non-15 PAH
Benzene
Polycyclic Organic Matter as 7-PAH
Polycyclic Organic Matter as 15-PAH
1,3 -Butadiene
Naphthalene
Lead
Arsenic
Acetaldehyde
Tetrachloroethylene
9.19E-04
8.04E-04
7.60E-04
3.26E-04
1.80E-04
1.43E-04
1.23E-04
4.98E-05
3.91E-05
3.53E-05
-------
Table 21-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for LAOR
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Union County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Union County)
Pollutant
Noncancer
Toxicity Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for LAOR)
Noncancer Risk
Pollutant (HQ)
La Grande, Oregon - LAOR
Toluene
Xylenes
Benzene
Methanol
Formaldehyde
Ethylbenzene
Methyl Ethyl Ketone
1,1,1 -Trichloroethane
Hexane
Methyl Isobutyl Ketone
175.86
113.14
103.09
98.82
56.80
27.15
25.55
24.86
22.64
19.35
Acrolein
Manganese
Hexamethylene Diisocyanate
Formaldehyde
Benzene
1,3 -Butadiene
4,4'-Methylenediphenyl Diisocyanate
Acetaldehyde
Naphthalene
Cyanide
217,747.26
16,119.69
15,194.00
5,796.03
3,436.27
3,000.00
2,941.68
1,974.40
1,406.40
1,162.11
-------
• Acrolein, which did not have one of the highest total emissions, had the highest
noncancer toxicity-weighted emissions.
• Only benzene and formaldehyde appeared on both lists.
Oregon Pollutant Summary
Oregon sampled for only hexavalent chromium and none of its measured detections failed
screens.
21-18
-------
22.0 Sites in Puerto Rico
This section presents meteorological, concentration, and spatial trends for the UATMP
sites in Puerto Rico (BAPR and SJPR). SJPR is located in San Juan, and BAPR is located
further west in Barceloneta. Both sites lie on the northern coast of Puerto Rico and are part of
the San Juan, PR MSA. Figures 22-1 and 22-2 are topographical maps showing the monitoring
sites in their urban and rural locations. Figures 22-3 and 22-4 identify point source emission
locations within 10 miles of each site as reported in the 2002 NEI for point sources. As
Figure 22-3 shows, many of the emission sources near BAPR are located just east of the
monitoring site and are involved in pharmaceutical production. Many of the emission sources
near SJPR are also located just east of the monitoring site and are involved in liquids distribution
and fabricated metal product production.
The island of Puerto Rico is located in the northern Caribbean and experiences a tropical
climate, where the air is warm and humid year-round and rainfall is abundant. Breezy winds
flow from the northeast to east on average with the aid of the sub-tropical high pressure that
resides over the tropical Atlantic Ocean. However, the sea-breeze is a daily occurrence (Ruffner
andBair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the Puerto Rico monitoring sites is Luis Munoz Marin International Airport (WBAN 11641).
Table 22-1 presents average meteorological conditions of temperature (average maximum and
average), moisture (average dew point temperature, average wet-bulb temperature, and average
relative humidity), pressure (average sea level pressure), and wind information (average scalar
wind speed) for the entire year and on days samples were collected. Also included in Table 22-1
is the 95 percent confidence interval for each parameter. As shown in Table 22-1, average
meteorological conditions on sampling days were fairly representative of average weather
conditions throughout the year.
22-1
-------
Figure 22-1. Barceloneta, Puerto Rico (BAPR) Monitoring Site
^^ifel?
1 '—a • ' • '//' ilvj (. -'( -aSP.:-
"• t'' :; -irJtwiy, •> •fi%8&?)
fim
-^^%^-^,-, j> |\. _,-^ V
^jMlk-' j w ~J>^ E
SX^^^V- i. I'Y^j. '
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
22-2
-------
Figure 22-2. San Juan, Puerto Rico (SJPR) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
22-3
-------
Figure 22-3. Facilities Located Within 10 Miles of BAPR
Note; Due to faoilrty d«m»it^ diad ^location, the toEal facilities
displaced may not represent all facilities within She area of interest.
•fa BAPR UATMP site
10 mile radius
I j County boundary
Source Category Group (No. of Facilities)
* Agricultural Chemicals Production Industrial Facility (1)
; Business Services Facility (1)
C Chemicals & Allied Products Facility (2)
F Fuel Combustion Industrial Facility (1)
> Pharmaceutical Production Processes Industrial Facility (10)
Q Primary Metal Industries Facility (1)
22-4
-------
Figure 22-4. Facilities Located Within 10 Miles of SJPR
San Juan
County / Trujtllq
/ Allo [
County
Legend
•& SJPR UATM P site
•" • 10 mile radius
| | County boundary
Source Category Group (No. of Facilities)
C Chemicals & Allied Products Facility (1)
D Fabricated Metal Products Facility (3)
F Fuel Combustion Industrial Facility (2)
L Liquids Distribution Industrial Facility (5)
P Miscellaneous Processes Industrial Facility (1)
P Petroleum/Nat. Gas Prod. & Refining Industrial Facility (1)
4 Production of Organic Chemicals Industrial Facility (1)
U Stone, Clay, Glass, 8 Concrete Products (1)
Note; Due to facility density and coflocation. the losal facilities
displayed may no! represent aM facilities within Ehe area of interest.
22-5
-------
Table 22-1. Average Meteorological Conditions near the Monitoring Sites in Puerto Rico
Site
BAPR
SJPR
WBAN
11641
11641
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
85.70
±0.36
85.37
±0.91
85.70
±0.36
85.27
±0.94
Average
Temperature
(°F)
79.81
±0.30
79.60
±0.75
79.81
±0.30
79.48
±0.79
Average
Dew Point
Temperature
(°F)
71.34
±0.32
71.01
±0.85
71.34
±0.32
71.04
±0.96
Average
Wet Bulb
Temperature
(op)
74.04
±0.28
73.77
±0.73
74.04
±0.28
73.76
±0.81
Average
Relative
Humidity
(%)
76.14
±0.55
75.74
±1.30
76.14
±0.55
76.06
±1.34
Average
Sea Level
Pressure
(mb)
1015.26
±0.22
1015.34
±0.57
1015.26
±0.22
1015.44
±0.62
Average
Scalar Wind
Speed
(kt)
6.15
±0.24
6.30
±0.65
6.15
±0.24
6.50
±0.72
to
to
-------
22.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Puerto Rico
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total screens. The Puerto Rico sites sampled for carbonyl
compounds and VOC only. Table 22-2 presents the pollutants that failed at least one screen at
the Puerto Rico monitoring sites.
Table 22-2. Comparison of Measured Concentrations and EPA Screening Values
for the Puerto Rico Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Barceloneta, Puerto Rico - BAPR
Acetaldehyde
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Acrolein
Dichloromethane
Formaldehyde
Xylenes
Tetrachloroethylene
Acrylonitrile
Hexachloro- 1 ,3 -butadiene
Toluene
Trichloroethylene
Chloroform
1 , 1 ,2,2-Tetrachloroethane
Ethyl Aery late
Total
59
57
57
57
56
46
44
8
5
4
4
3
2
1
1
1
1
406
59
57
57
57
57
46
57
59
57
24
4
o
6
57
6
53
1
1
655
100.00
100.00
100.00
100.00
98.25
100.00
77.19
13.56
8.77
16.67
100.00
100.00
3.51
16.67
1.89
100.00
100.00
61.98
14.53
14.04
14.04
14.04
13.79
11.33
10.84
1.97
1.23
0.99
0.99
0.74
0.49
0.25
0.25
0.25
0.25
14.53
28.57
42.61
56.65
70.44
81.77
92.61
94.58
95.81
96.80
97.78
98.52
99.01
99.26
99.51
99.75
100.00
22-7
-------
Table 22-2. Comparison of Measured Concentrations and EPA Screening Values
for the Puerto Rico Monitoring Sites (Continued)
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
San Juan, Puerto Rico - SJPR
Formaldehyde
1,3 -Butadiene
Acetaldehyde
Benzene
Carbon Tetrachloride
£>-Dichlorobenzene
Acrolein
Tetrachloroethylene
Xylenes
Dichloromethane
Acrylonitrile
Chloromethylbenzene
1 ,2-Dichloroethane
Hexachloro- 1 ,3 -butadiene
Total
40
40
40
40
40
39
36
29
9
7
2
1
1
1
325
40
40
40
40
40
40
36
37
40
40
2
1
1
1
398
100.00
100.00
100.00
100.00
100.00
97.50
100.00
78.38
22.50
17.50
100.00
100.00
100.00
100.00
81.66
12.31
12.31
12.31
12.31
12.31
12.00
11.08
8.92
2.77
2.15
0.62
0.31
0.31
0.31
12.31
24.62
36.92
49.23
61.54
73.54
84.62
93.54
96.31
98.46
99.08
99.38
99.69
100.00
The following observations are shown in Table 22-2:
• Seventeen pollutants with a total of 406 measured concentrations failed the screen at
BAPR and 14 pollutants with a total of 325 measured concentrations failed the screen
at SJPR.
• While the pollutants of interest varied by site, the following eight pollutants
contributed to the top 95 percent of the total failed screens at each Puerto Rico
monitoring site: benzene, acetaldehyde, carbon tetrachloride, formaldehyde, 1,3-
butudiene, xylenes, />-dichlorobenzene, and acrolein.
• Of the eight pollutants that were the same for both sites, five pollutants of interest
(acetaldehyde, benzene, carbon tetrachloride, 1,3-butadiene, and acrolein) had 100
percent of their measured detections fail the screening values at both sites.
• Formaldehyde failed 100 percent of screens at SJPR, but failed only 8 of 59 screens at
BAPR.
22.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
22-8
-------
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. The daily and seasonal average concentrations
are presented in Table 22-3. Annual averages are presented and discussed in further detail in
later sections.
The following observations for BAPR are shown in Table 22-3:
• Acetaldehyde, benzene, 1,3-butadiene, carbon tetrachloride, />-dichlorobenzene,
formaldehyde, xylenes, and dichloromethane were detected in every sample collected
at BAPR.
• Among the daily averages for BAPR, dichloromethane had the highest concentration
by mass (10.05 ± 3.55 |ig/m3), followed by xylenes (4.68 ± 1.41 |ig/m3) and
acetaldehyde (1.98 ± 0.28 |ig/m3).
• The seasonal averages of dichloromethane had large confidence intervals, which may
indicate that the averages are influenced by outliers. This was also true of the spring
xylenes average, the spring acrolein average, and the spring and autumnp-
dichlorobenzene averages.
The following observations for SJPR are shown in Table 22-3:
• Among the daily averages, total xylenes had the highest concentration by mass (8.46
± 2.16 |ig/m3), followed by acetaldehyde (2.60 ± 0.64 |ig/m3) and benzene (1.87 ±
0.29 |ig/m3).
• The winter and summer averages ofp-dichlorobenzene also had large confidence
intervals, suggesting averages influenced by outliers.
• No seasonal average was available for spring because samples were not collected in
May.
• Acetaldehyde, benzene, carbon tetrachloride, formaldehyde, 1,3-butadiene, p-
dichlorobenzene, and total xylenes were detected in every sample collected at SJPR.
22-9
-------
Table 22-3. Daily and Seasonal Averages for the Pollutants of Interest for the Puerto Rico Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Ug/m3)
Conf.
Int.
Autumn
Avg
(Ug/m3)
Conf.
Int.
Barceloneta, Puerto, Rico - BAPR
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
/>-Dichlorobenzene
Dichloromethane
Formaldehyde
Xylenes
59
46
57
57
57
57
57
59
57
59
57
57
57
57
57
57
59
57
1.98
1.05
1.21
0.13
0.72
1.05
10.05
0.72
4.68
0.28
0.53
0.27
0.03
0.06
0.71
3.55
0.06
1.41
2.15
0.39
0.85
0.11
0.55
0.60
15.39
0.73
2.96
0.42
0.15
0.18
0.02
0.07
0.54
8.90
0.08
1.18
2.76
1.23
1.78
0.19
0.68
1.55
9.54
0.90
7.38
0.52
1.51
0.90
0.08
0.07
2.12
8.15
0.11
4.53
1.62
0.63
0.90
0.08
0.80
0.40
6.75
0.62
3.30
0.55
0.17
0.15
0.02
0.12
0.18
4.59
0.07
0.87
1.36
1.19
1.24
0.14
0.88
1.52
7.87
0.62
4.80
0.50
0.53
0.18
0.02
0.10
1.48
3.49
0.14
1.86
San Juan, Puerto, Rico - SJPR
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
/>-Dichlorobenzene
Formaldehyde
Tetrachloroethylene
Xylenes
40
36
40
40
40
40
40
37
40
40
40
40
40
40
40
40
40
40
2.60
1.20
1.87
0.21
0.74
1.76
1.80
0.40
8.46
0.64
0.48
0.29
0.03
0.06
1.38
0.13
0.23
2.16
2.83
0.78
1.77
0.23
0.62
4.19
2.01
NA
6.48
1.38
0.49
0.50
0.08
0.09
5.12
0.41
NA
2.25
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
1.59
0.65
1.91
0.18
0.76
1.70
1.66
0.31
10.82
0.38
0.20
0.65
0.05
0.09
2.37
0.18
0.14
5.44
1.81
1.88
1.96
0.23
0.83
0.82
1.85
0.59
8.05
0.22
1.21
0.39
0.07
0.08
0.31
0.20
0.62
2.11
to
to
NA = Not available
NR = No reportable
due to short sampling duration.
due to the low number of measured detections.
-------
22.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for Puerto Rico monitoring sites was
evaluated using ATSDR short-term (acute) and intermediate MRL and California EPA acute
REL factors. Acute risk is defined as exposures from 1 to 14 days while intermediate risk is
defined as exposures from 15 to 364 days. It is useful to compare the preprocessed daily
measurements to the short-term MRL and REL factors, as well as compare seasonal averages to
the intermediate MRL. Of the pollutants with at least one failed screen, only acrolein exceeded
either the acute or the intermediate risk values, and each site's non-chronic risk is summarized in
Table 22-4.
The following observations about acrolein are shown in Table 22-4:
• All of the acrolein measured detections at the Puerto Rico monitoring sites were
greater than the ATSDR acute value of 0.11 |ig/m3, and all but one exceeded the
California REL value of 0.19 |ig/m3.
• The average measured concentration was 1.05 ± 0.53 |ig/m3 for BAPR and 1.20 ±
0.48 |ig/m3 for SJPR, which were an order of magnitude higher than either acute risk
factor.
• All seasonal averages for acrolein were at least one order of magnitude higher than
the intermediate risk factor.
For the pollutants that exceeded the short-term (acute) risk factors, the concentrations
were further examined by developing pollution roses for these pollutants. A pollution rose is a
plot of concentration and wind direction. For both Puerto Rico monitoring sites, only acrolein
concentrations exceeded the acute risk factors. Figures 22-5 and 22-6 are pollution roses for
acrolein for the Puerto Rico sites. As shown in Figures 22-5 and 22-6, and discussed above,
nearly all acrolein concentrations exceeded the acute risk factors, which are indicated by a
dashed line (CALEPA REL) and solid line (ATSDR MRL).
Observations gleaned from the acrolein pollution rose for BAPR include:
• Figure 22-5 for BAPR shows that concentrations exceeding the acute risk factors
occurred with winds generally originating from the east. But, winds originated out of
the east at BAPR on a majority of the sampling days.
22-11
-------
Table 22-4. Non-Chronic Risk Summary for the Puerto Rico Monitoring Sites
Site
BAPR
SJPR
Method
TO-15
TO-15
Pollutant
Acrolein
Acrolein
Daily
Average
(ug/m3)
1.05 ±0.53
1.20 ±0.48
ATSDR
Short-term
MRL
(ug/m3)
0.11
0.11
# of ATSDR
MRL
Exceedances
46
36
CAL EPA
REL Acute
(ug/m3)
0.19
0.19
# of CAL
EPA REL
Exceedances
45
36
ATSDR
Intermediate-
term MRL
(ug/m3)
0.09
0.09
Winter
Average
(Ug/m3)
0.39
±0.15
0.78
±0.49
Spring
Average
(ug/m3)
1.23
±1.51
NR
Summer
Average
(Ug/m3)
0.63
±0.17
0.65
±0.20
Autumn
Average
(Ug/m3)
1.19
±0.53
1.88
± 1.21
NA = Not available due to short sampling duration.
NR = No reportable due to the low number of measured detections.
to
to
-------
Figure 22-5. Acrolein Pollution Rose for BAPR
to
to
12.0
10.0
8.0
6.0
4.0
2.0
u
O 0.0
O
O
Q.
2.0
4.0
6.0
8.0
10.0
12.0
NW
W
SW
12.0
— CA EPA REL (0.19 |jg/rrr
— ATSDRMRL(0.11 |jg/m3
NE
Daily Avg Cone =1.05 ± 0.53 ug/nr
SE
10.0 8.0 6.0 4.0 2.0 0.0 2.0
Pollutant Concentration
4.0
6.0
8.0
10.0
12.0
-------
Figure 22-6. Acrolein Pollution Rose for SJPR
to
to
12.0
10.0
8.0
6.0
NE
4.0
.0
I
'c
u
c
o
o
'c
re
o
Q.
— CA EPA REL 0.19 ug/m
ATSDR MRL 0.11 ug/m
6.0
8.0
10.0
12.0
12.0 10.0 8.0 6.0 4.0 2.0 0.0 2.0
Pollutant Concentration
Daily Ava Cone =1.20 ± 0.48 ua/nr
4.0 6.0 8.0 10.0
12.0
-------
• The highest concentration of acrolein was measured on May 5, 2006, a day with a
northeasterly wind.
• BAPR is located just north of a maj or road through Barceloneta, a town that lies to
the west of San Juan. The immediate vicinity is classified as residential and rural.
Several pharmaceutical production sources are located east of the monitoring site.
Observations gleaned from the acrolein pollution rose for SJPR include:
• Figure 22-6 for SJPR shows that most of the concentrations exceeding the acute risk
factors occurred with winds originating from the east. But, winds originated out of
the east at SJPR on a majority of the sampling days.
• The highest concentration of acrolein was measured on November 7, 2006, a day with
an easterly wind.
• SJPR is located between several major roadways, including Highway 22, 5, and 167,
just west of Fort Buchanan and Luchetti Industrial Park
22.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
22.4.1 Pearson Correlation Analysis
Table 22-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters at the Puerto Rico monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for BAPR from Table 22-5:
• Most of the correlations for BAPR were weak.
• Carbon tetrachloride exhibited strong positive correlations with maximum, average,
and wet bulb temperatures, indicating that as temperature and moisture content
increase, concentrations of carbon tetrachloride also increase.
The following observations are gathered for SJPR from Table 22-5:
22-15
-------
Table 22-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Puerto
Rico Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Barceloneta, Puerto Rico - BAPR
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Carbon Tetrachloride
Dichloromethane
Formaldehyde
£>-Dichlorobenzene
Xylenes
57
59
46
57
57
57
59
57
57
-0.13
-0.26
-0.07
-0.02
0.59
0.03
-0.18
-0.05
-0.10
-0.06
-0.34
0.03
0.02
0.58
-0.01
-0.20
0.05
0.00
-0.17
-0.48
-0.27
-0.18
0.45
-0.01
-0.27
-0.09
-0.18
-0.13
-0.46
-0.19
-0.12
0.52
-0.02
-0.26
-0.04
-0.13
-0.19
-0.33
-0.48
-0.31
-0.07
0.01
-0.18
-0.22
-0.29
-0.20
0.12
-0.14
-0.16
-0.15
0.06
0.00
-0.15
-0.16
0.05
-0.01
0.01
-0.04
-0.08
-0.01
-0.14
-0.04
0.04
San Juan, Puerto Rico - SJPR
1,3 -Butadiene
Acetaldehyde
Acrolein
Benzene
Carbon Tetrachloride
Formaldehyde
£>-Dichlorobenzene
Tetrachloroethylene
Xylenes
40
40
36
40
40
40
40
37
40
-0.29
-0.44
0.01
0.02
0.37
-0.04
-0.28
-0.23
0.17
-0.39
-0.55
-0.04
-0.03
0.39
-0.21
-0.30
-0.15
0.13
-0.25
-0.70
-0.09
0.10
0.42
-0.41
-0.24
0.05
0.17
-0.29
-0.68
-0.08
0.07
0.43
-0.37
-0.27
0.00
0.17
0.09
-0.45
-0.10
0.22
0.19
-0.40
-0.01
0.26
0.11
-0.18
0.22
-0.30
-0.09
-0.23
-0.02
0.11
-0.27
0.02
-0.37
-0.02
-0.11
-0.37
-0.33
-0.21
0.04
-0.12
-0.19
to
to
-------
• Similar to BAPR, most of the correlations for SJPR were weak.
• Acetaldehyde exhibited strong negative correlations with average, dew point, and wet
bulb temperatures, indicating that as temperature and moisture content increase,
concentrations of acetaldehyde tend to decrease.
22.4.2 Composite Back Trajectory Analysis
Figures 22-7 and 22-8 are composite back trajectory maps for the Puerto Rico monitoring sites
for the days on which sampling occurred. Each line represents the 24-hour trajectory along
which a parcel of air traveled toward the monitoring site on a sampling day. Each concentric
circle around the site represents 100 miles.
The following observations can be made from Figures 22-7 and 22-8:
• Back trajectories predominantly originated from the east at BAPR and SJPR.
• The 24-hour airshed domains are somewhat smaller for the Puerto Rico monitoring
sites than other UATMP sites, both in size and directional variation.
• Few back trajectories originated over 600 miles away, with most of the trajectories
originating within 400 miles of the sites.
22.4.3 Wind Rose Analysis
Hourly wind data from the Luis Munoz Marin International Airport were uploaded into a
wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces a graphical wind
rose from the wind data. A wind rose shows the frequency of wind directions about a 16-point
compass, and uses different shading to represent wind speeds. Figures 22-9 and 22-10 are the
wind roses for the Puerto Rico monitoring sites on days that sampling occurred.
The following observations can be made from Figures 22-9 and 22-10:
• The wind roses for these sites look very similar.
• Hourly winds were predominantly out of the east (approximately 30 percent of
observations) and east-northeast (approximately 20 percent) near BAPR and SJPR on
days samples were collected.
22-17
-------
Figure 22-7. Composite Back Trajectory Map for BAPR
to
to
K-1
OO
-------
Figure 22-8. Composite Back Trajectory Map for SJPR
to
to
K-1
VO
-------
Figure 22-9. Wind Rose for BAPR Sampling Days
WEST
to
to
to
o
SOUTH .--
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
^| 11 - 17
I I 4- 7
• 2- 4
Calms: 21.51%
-------
Figure 22-10. Wind Rose for SJPR Sampling Days
WEST
to
to
to
SOUTH .--
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
^| 11 - 17
I I 4- 7
• 2- 4
Calms: 20.45%
-------
• Calm winds were observed for about 20 percent of the observations near each site,
although wind speeds of 7 to 11 knots were recorded most frequently.
• Winds were stronger when originating out of the east-northeast.
22.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as these sites did not sample for SNMOC.
22.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Bayamon and Barceloneta
Municipios were obtained from the Air Monitoring Division of Puerto Rico's Air Quality
Program and the U.S. Census Bureau, and are summarized in Table 22-6. Table 22-6 also
includes a vehicle registration to county population ratio (vehicles per person). Finally,
Table 22-6 contains the average daily traffic information, which represents the average number
of vehicles passing the monitoring sites on the nearest roadway to each site on a daily basis. Ten
mile population data was not available for the Puerto Rico sites.
Observations gleaned from Table 22-6 include:
• The BAPR monitoring site has a significantly lower county population than the SJPR
site, as well as a lower county vehicle ownership.
• Compared to other UATMP sites, Barceloneta County has the second lowest county
population and the lowest vehicle registration.
• Both sites have comparatively low registration-populations ratios.
• While the daily traffic flow near B APR is significantly lower than at SJPR, these two
sites experience the second and fifth lowest traffic volumes (respectively) compared
to other UATMP locations.
22.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4.). Table 3-12 and Figure
22-22
-------
Table 22-6. Motor Vehicle Information for the Puerto Rico Monitoring Sites
Site
BAPR
SJPR
2006 Estimated
County
Population
23,028
221,546
Number of
Vehicles
Registered
13,912
145,642
Vehicles per Person
(Registration:
Population)
0.60
0.66
Population
Within 10 Miles
NA
NA
Estimated 10 mile
Vehicle
Ownership
NA
NA
Traffic Data
(Daily Average)
10
250
to
to
to
-------
3-4 depict the average concentration ratios of the roadside study and compared them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• The benzene-ethylbenzene and xylenes-ethylbenzene ratios for BAPR and SJPR
closely resemble those of the roadside study.
• This indicates that mobile sources may contribute appreciably to concentrations
measured at the Puerto Rico sites.
22.6 Trends Analysis
A trends analysis could not be performed for the Puerto Rico sites as they have not
participated in the UATMP for three consecutive years.
22.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Puerto Rico sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 22-7.
Additionally, the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA were
retrieved and are also presented in Table 22-7. The NATA data are presented for the census
tracts where the monitoring sites are located.
The census tract information for the Puerto Rico sites is as follows:
• The census tract for BAPR is 72017590300, which had a population of 6,625, which
represents approximately 30 percent of the Barceloneta Municipio population in
2000.
• The census tract for SJPR is 72021030103, which had a population of 4,814, which
represents approximately 2 percent of the Bayamon Municipio population in 2000.
The following observations can be made for BAPR from Table 22-7:
• Dichloromethane, toluene, and total xylenes had the highest annual averages by mass
concentration for BAPR as well as the highest NATA-modeled concentrations.
22-24
-------
Table 22-7. Chronic Risk Summary for the Monitoring Sites in Puerto Rico
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(Hg/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Barceloneta, Puerto Rico (BAPR) - Census Tract ID 72017590300
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
Chloroform
p-Dichlorobenzene
Dichloromethane
Ethyl Aery late
Formaldehyde
Hexachloro- 1 ,3 -butadiene
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
Trichloroethylene
Xylenes
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
NR
0.000011
0.00000047
0.000014
5.5E-09
0.000022
0.000058
0.0000059
NR
0.000002
NR
0.009
0.00002
0.002
0.03
0.002
0.04
0.098
0.8
1
NR
0.0098
0.09
NR
0.27
0.4
0.6
0.1
0.27
0.13
0.01
2.10
0.13
0.69
0.42
0.06
151.06
0.01
1.01
O.01
0.01
0.25
14.72
0.12
3.91
0.59
NR
0.01
16.41
3.79
10.35
NR
0.62
71.00
0.01
0.01
0.03
0.01
1.45
NR
0.23
NR
0.03
6.42
0.01
0.07
0.06
0.02
O.01
0.01
0.15
NR
0.10
O.01
NR
O.01
0.04
0.01
0.04
1.98 ±0.28
0.87 ±0.44
0.08 ±0.02
1.21 ±0.27
0.13 ±0.03
0.72 ±0.06
0.46 ±0.41
1.05 ±0.71
10.05 ±3. 55
0.04 ±0.03
0.72 ±0.06
0.09 ±0.02
0.05 ±0.01
0.09 ±0.05
8.07 ±6.32
0.07 ± 0.06
4.68 ±1.41
4.35
NR
5.43
9.43
4.01
10.84
NR
11.56
4.73
0.50
O.01
1.90
2.89
0.56
NR
0.14
NR
0.22
43.47
0.04
0.04
0.07
0.02
O.01
0.01
0.01
NR
0.07
O.01
NR
O.01
0.02
0.01
0.05
San Juan, Puerto Rico (SJPR) - Census Tract ID 72021030103
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
Chloromethylbenzene
p-Dichlorobenzene
1 ,2-Dichloroethane
Dichloromethane
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000049
0.000011
0.000026
0.00000047
0.009
0.00002
0.002
0.03
0.002
0.04
NR
0.8
2.4
1
0.22
0.14
0.01
2.19
0.08
0.70
0.01
0.18
0.05
1.48
0.49
NR
0.16
17.06
2.44
10.48
0.01
1.98
1.25
0.69
0.02
7.15
0.01
0.07
0.04
0.02
NR
0.01
O.01
0.01
2.60 ± 0.64
1.09 ±0.45
0.08 ±0.03
1.87 ±0.29
0.21 ±0.03
0.74 ±0.06
0.02 ±0.01
1.76 ±1.38
0.03 ±O.01
5.88 ±7.49
5.72
NR
5.69
14.6
6.32
11.08
0.82
19.37
0.84
2.76
0.29
54.66
0.04
0.06
0.11
0.02
NR
0.01
O.01
0.01
to
to
to
-------
to
to
to
Table 22-7. Chronic Risk Summary for the Monitoring Sites in Puerto Rico (Continued)
Pollutant
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
Xylenes
Cancer
URE
Oig/m3)
5.5E-09
0.000022
0.0000059
NR
Noncancer
RfC
Oig/m3)
0.0098
0.09
0.27
0.1
1999 NATA
Modeled
Concentration
(Hg/m3)
0.83
<0.01
3.06
4.20
Cancer Risk
(in-a-
million)
<0.01
0.03
18.04
NR
Noncancer
Risk (HQ)
0.08
<0.01
0.01
0.04
2006 UATMP
Annual
Average
(Hg/m3)
1.80 ±0.13
0.08 ±0.01
0.37 ±0.22
8.46 ±2. 16
Cancer
Risk (in-a-
million)
0.01
1.70
2.21
NR
Noncancer
Risk (HQ)
0.18
<0.01
<0.01
0.08
* BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
-------
• The NATA-modeled dichloromethane concentration was an order of magnitude
higher than the annual average.
• />-Dichlorobenzene, carbon tetrachloride, and benzene had the three highest cancer
risks based on annual averages, while dichloromethane, benzene, and carbon
tetrachloride had the three highest cancer risks based on NATA.
• The NATA-based and annual average-based cancer risks for some pollutants, such as
carbon tetrachloride, were very similar, while others were very different, such as
dichloromethane.
• The dichloromethane NATA cancer risk was the second highest cancer risk for a
pollutant of interest for any UATMP site (behind only arsenic for ININ).
• Acrolein was the only pollutant that exhibited a noncancer HQ greater than 1,
according to both the 2006 annual average and the 1999 NATA, although the annual
average-based noncancer risk was much higher.
• All other noncancer HQs were less than 0.25.
The following observations can be made for SJPR from Table 22-7:
• Xylenes, dichloromethane, and acetaldehyde had the highest annual averages by mass
concentration for SJPR, while xylenes, tetrachloroethylene, and benzene had the
highest NATA-modeled concentrations.
• />-Dichlorobenzene, benzene, and carbon tetrachloride had the three highest cancer
risks based on annual averages, while tetrachloroethylene, benzene, and carbon
tetrachloride had the three highest cancer risks based on NATA.
• The NATA-based and annual average-based cancer risks for some pollutants, such as
carbon tetrachloride, were very similar, while others were very different, such as
acrylonitrile.
• Acrolein was the only pollutant that exhibited a noncancer HQ greater than 1,
according to both the 2006 annual average and the 1999 NATA, although the annual
average-based noncancer risk was much higher.
• SJPR had one of the highest acrolein annual averaged-based noncancer risk among
UATMP sites, behind only two sites in Oklahoma.
• All other noncancer HQs, both NATA-modeled and annual average-based, were less
than 0.30.
22-27
-------
22.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 22-8 and 22-9 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 22-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 22-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. In addition, the highest cancer and noncancer risks based on annual
averages are limited to those pollutants failing at least one screen.
The following observations can be made from Table 22-8:
• Dichloromethane was the highest emitted pollutant with a cancer risk factor, had the
highest cancer toxicity-weighted emissions, and had the fifth highest cancer risk
based on the 2006 annual average for BAPR. The emissions, toxicity-weighted
emissions, and cancer risk for this pollutant for SJPR were lower.
• Benzene was the highest emitted pollutant with a cancer risk factor, had the highest
cancer toxicity-weighted emissions, and had the second highest cancer risk based on
the 2006 annual average for SJPR.
• />-Dichlorobenzene had the highest cancer risk based on the 2006 annual average for
both BAPR and SJPR, yet this pollutant was neither one of the highest emitted nor
one of the most toxic based on the 2002 NEI emission inventory.
The following observations can be made from Table 22-9:
• Dichloromethane was the highest emitted pollutant with a noncancer risk factor, had
the seventh highest noncancer toxicity-weighted emissions, and had the tenth highest
noncancer risk based on the 2006 annual average for BAPR.
• Acrolein had the highest noncancer toxicity-weighted emissions in Barceloneta
County and had the highest noncancer risks based on the 2006 annual average for
BAPR. The same was true for Bayamon County and SJPR.
22-28
-------
Table 22-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Puerto Rico
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer Risk
(in-a-million)
Barceloneta, Puerto Rico (BAPR) - Barceloneta Municipio
Dichloromethane
Benzene
Formaldehyde
Tetrachloroethylene
Acetaldehyde
1,3 -Butadiene
Naphthalene
Poly cyclic Organic Matter as 15 -PAH
Ethylene Oxide
Hexavalent Chromium
346.71
12.11
4.02
1.87
1.69
1.34
0.14
0.04
0.03
0.03
Dichloromethane
Hexavalent Chromium
Benzene
Arsenic
1,3 -Butadiene
Tetrachloroethylene
Naphthalene
Acetaldehyde
Polycyclic Organic Matter as 7-PAH
Ethylene Oxide
1.63E-04
1.15E-04
9.44E-05
4.15E-05
4.03E-05
1.10E-05
4.62E-06
3.72E-06
2.82E-06
2.75E-06
£>-Dichlorobenzene
Carbon Tetrachloride
Benzene
Acrylonitrile
Dichloromethane
Acetaldehyde
1,3 -Butadiene
1 , 1 ,2,2-Tetrachloroethane
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
11.56
10.84
9.43
5.43
4.73
4.35
4.01
2.89
1.90
0.56
San Juan, Puerto Rico (SJPR) - Bayamon Municipio
Benzene
Formaldehyde
Acetaldehyde
Tetrachloroethylene
1,3 -Butadiene
Dichloromethane
Naphthalene
Poly cyclic Organic Matter as 15-PAH
Chromium III
Hexavalent Chromium
179.30
56.89
22.64
22.10
19.48
16.99
2.77
0.55
0.30
0.30
Benzene
Hexavalent Chromium
1,3 -Butadiene
Arsenic
Tetrachloroethylene
Naphthalene
Acetaldehyde
Polycyclic Organic Matter as 7-PAH
Polycyclic Organic Matter as 15-PAH
Ethylene Oxide
1.40E-03
1.05E-03
5.84E-04
3.33E-04
1.30E-04
9.43E-05
4.98E-05
3.69E-05
3.02E-05
2.42E-05
/>-Dichlorobenzene
Benzene
Carbon Tetrachloride
1,3 -Butadiene
Acetaldehyde
Acrylonitrile
Dichloromethane
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
1 ,2-Dichloroethane
19.37
14.60
11.08
6.32
5.72
5.69
2.76
2.21
1.70
0.84
to
to
to
VO
-------
Table 22-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Puerto Rico
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk
(HQ)
Barceloneta, Puerto Rico (BAPR) - Barceloneta Municipio
Dichloromethane
Toluene
Xylenes
Acetonitrile
Methanol
Benzene
Ethylbenzene
Hexane
Formaldehyde
Hydrochloric Acid
346.71
41.31
34.62
29.95
12.29
12.11
8.39
6.96
4.02
2.01
Acrolein
Chlorine
1,3 -Butadiene
Acetonitrile
Formaldehyde
Benzene
Dichloromethane
Xylenes
Arsenic
Acetaldehyde
9,987.03
2,150.02
672.05
499.09
410.06
403.60
346.71
346.23
321.32
187.85
Acrolein
Acetaldehyde
Formaldehyde
1,3 -Butadiene
Xylenes
Benzene
Acrylonitrile
Toluene
Carbon Tetrachloride
Dichloromethane
43.47
0.22
0.07
0.07
0.05
0.04
0.04
0.02
0.02
0.01
San Juan, Puerto Rico (SJPR) - Bayamon Municipio
Toluene
Xylenes
Benzene
Hexane
Ethylbenzene
Formaldehyde
Methyl 7er/-Butyl Ether
Acetaldehyde
Tetrachloroethylene
1,3 -Butadiene
545.64
428.41
179.30
132.60
105.81
56.89
30.38
22.64
22.10
19.48
Acrolein
1,3 -Butadiene
Benzene
Formaldehyde
Xylenes
Arsenic
Acetaldehyde
Toluene
Nickel
Naphthalene
142,465.88
9,740.29
5,976.57
5,805.58
4,284.09
2,582.58
2,516.00
1,364.11
1,050.58
924.56
Acrolein
Acetaldehyde
Formaldehyde
1,3 -Butadiene
Xylenes
Benzene
Acrylonitrile
Carbon Tetrachloride
Dichloromethane
/>-Dichlorobenzene
54.66
0.29
0.18
0.11
0.08
0.06
0.04
0.02
0.01
<0.01
to
to
-------
• While/>-dichlorobenzene had the highest annual average-based cancer risk for both
sites, the noncancer risk attributable to/?-dichlorobenzene was very low.
Puerto Rico Pollutant Summary
• The pollutants of interest common to each Puerto Rico site were acetaldehyde, acrolein,
benzene, 1,3-butadiene, carbon tetrachloride, p-dichlorobenzene, formaldehyde, and
xylenes.
• Dichloromethane had the highest daily average for BAPR, while total xylenes had
highest average for SJPR.
• Acrolein exceeded the short-term risk factors at both Puerto Rico sites.
22-31
-------
23.0 Site in Rhode Island
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Rhode Island (PRRI). This site is located in the Providence MSA. Figure 23-1 is a
topographical map showing the monitoring site in its urban location. Figure 23-2 identifies point
source emission locations within 10 miles of this site that reported to the 2002 NEI for point
sources. PRRI is surrounded by a very large number of industrial sources. A majority of the
sources are involved in fuel combustion and surface coating processes.
Providence is a coastal city on the Narragansett Bay, which opens to the Rhode Island
Sound and the Atlantic Ocean. Its proximity to the Sound and the Atlantic temper cold air
outbreaks and breezes off the ocean moderate summertime heat. On average, southerly and
southwesterly winds in the summer become northwesterly in the winter. Weather is fairly
variable in the region as frequent storm systems affect New England (Ruffner and Bair, 1987).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the PRRI monitoring site is at Theodore F. Green State Airport (WBAN 14739).
Table 23-1 presents the average meteorological conditions of temperature (average
maximum and average), moisture (average dew point temperature, average wet-bulb
temperature, and average relative humidity), pressure (average sea level pressure), and wind
information (average scalar wind speed) for the entire year and on days samples were collected.
Also included in Table 23-1 is the 95 percent confidence interval for each parameter. As shown
in Table 23-1, average meteorological conditions on sampling days were representative of
average weather conditions throughout the year.
23.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Rhode Island
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
23-1
-------
Figure 23-1. Providence, Rhode Island (PRRI) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
23-2
-------
Figure 23-2. Facilities Located Within 10 Miles of PRRI
Legend
"&• PRRI UATMP site ' 10 mile radius |
Source Category Group (No, of Facilities)
¥ Automotive Repair, Services, & Parking (2)
c Chemicals & Allied Products Facility (9)
5 Educational Services Facility (1)
z Electrical & Electronic Equipment Facility (3)
• Engineering & Management Services Facility (1)
D Fabricated Metal Products Facility (6)
F Fuel Combustion Industrial Facility (154)
+ Health Services Facility (5)
l Incineration Industrial Facility (1)
J Industrial Machinery & Equipment Facility (5)
Instruments & Related Products Facility (2)
L Liquids Distribution Industrial Facility (4)
a Lumber & Wood Products Facility (2)
B Mineral Products Processing Industrial Facility (6)
Nose: Due to fadlrty density and collocation, the total facilities
displayed may not represent ali facilities within the area of interest.
County boundary
x Miscellaneous Manufacturing Industries (12)
P Miscellaneous Processes Industrial Facility (70)
' Miscellaneous Repair Services (1)
\ Non-ferrous Metals Processing Industrial Facility (5)
@ Papers Allied Products (1)
> Pharmaceutical Production Processes Industrial Facility (2)
v Polymers & Resins Production Industrial Facility (5)
Q Primary Metal Industries Facility (3)
4 Production of Organic Chemicals Industrial Facility (2)
Y Rubber & Miscellaneous Plastic Products Facility (4)
u stone, Clay, Glass, & Concrete Products (2)
s Surface Coating Processes Industrial Facility (54)
8 Utility Boilers (2)
i Waste Treatment & Disposal industrial Facility (3)
r Wholesale Trade (2)
23-3
-------
Table 23-1. Average Meteorological Conditions near the Monitoring Site in Rhode Island
Site
PRRI
WBAN
14765
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
61.68
±1.64
61.59
±3.92
Average
Temperature
(»F)
53.56
±1.57
53.82
±3.76
Average
Dew Point
Temperature
(°F)
41.63
±1.85
42.42
±4.39
Average
Wet Bulb
Temperature
(°F)
48.11
±1.52
48.52
±3.63
Average
Relative
Humidity
(%)
66.93
±1.56
68.05
±3.64
Average
Sea Level
Pressure
(mb)
1015.09
±0.78
1015.63
±1.86
Average
Scalar Speed
Wind
(kt)
7.74
±0.30
7.13
±0.62
to
-U
-------
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. The PRRI site sampled for hexavalent
chromium only. Table 23-2 presents risk screening results at PRRI.
The following observations are shown in Table 23-2:
• A total of three measured concentrations failed screens.
• Six percent of the 50 measured detections failed screens.
Table 23-2. Comparison of Measured Concentrations and EPA Screening Values
for the Rhode Island Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Providence, Rhode Island - PRRI
Hexavalent Chromium
3
50
6.00
100.00
100.00
23.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
23-5
-------
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 23-3. Annual averages are presented and discussed in further detail in later
sections.
The following observations for PRRI are shown in Table 23-3:
• The daily average concentration for hexavalent chromium for PRRI was 0.032 ±
0.008 ng/m3.
• The highest seasonal average of hexavalent chromium was calculated for summer
(0.038 ± 0.022 ng/m3), while the lowest seasonal average was calculated for winter
(0.018 ± 0.009 ng/m3). However, these differences were not statistically significant,
as indicated by the confidence intervals.
23.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for PRRI was evaluated using ATSDR short-
term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is defined
as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15 to 364
days. It is useful to compare the preprocessed daily measurement to the short-term MRL and
REL factors, as well as compare the seasonal averages to the intermediate MRL. No hexavalent
chromium seasonal average exceeded the intermediate risk value. Acute risk could not be
assessed because hexavalent chromium has no acute risk factors.
23.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
23.4.1 Pearson Correlation Analysis
Table 23-4 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the PRRI monitoring site. (Please
refer to Section 3.1.6 for more information on Pearson correlations.) All the correlations
23-6
-------
Table 23-3. Daily and Seasonal Averages for the Pollutants of Interest for the Rhode Island Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
Providence, Rhode Island - PRRI
Hexavalent Chromium
50
61
0.032
0.008
0.018
0.009
0.033
0.011
0.038
0.022
0.022
0.012
to
oo
-------
Table 23-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Rhode
Island Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Providence, Rhode Island - PRRI
Hexavalent Chromium
50
0.11
0.12
0.18
0.16
0.19
0.05
-0.05
to
oo
oo
-------
between hexavalent chromium and the meteorological parameters were weak, indicating that
meteorology has little influence on concentrations of hexavalent chromium.
23.4.2 Composite Back Trajectory Analysis
Figure 23-3 is a composite back trajectory map for the PRRI monitoring site for the days
on which sampling occurred. Each line represents the 24-hour trajectory along which a parcel of
air traveled toward the monitoring site on a sampling day. Each concentric circle around the site
in Figure 23-3 represents 100 miles.
The following observations can be made from Figure 23-3:
• Back trajectories originated from a variety of directions at PRRI.
• The 24-hour airshed domain was large at PRRI, with trajectories originating as far
away as northern Quebec, Canada (~ 700 miles).
• The majority of the trajectories originated within 500 miles of the site.
23.4.3 Wind Rose Analysis
Hourly wind data from the Theodore F. Green State Airport near the PRRI monitoring
site were uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT
produces a graphical wind rose from the wind data. A wind rose shows the frequency of wind
directions about a 16-point compass, and uses different shading to represent wind speeds.
Figure 23-4 is the wind rose for the PRRI monitoring site on days that sampling occurred.
Observations from Figure 23-4 for PRRI include:
• Hourly winds were predominantly out of the west (11 percent of observations), south
(11 percent), and west-northwest (9 percent) on sampling days.
• Wind speeds most frequently ranged from 7 to 11 knots on days samples were
collected.
• Calm winds (<2 knots) were recorded for 10 percent of the observations.
23-9
-------
Figure 23-3. Composite Back Trajectory Map for PRRI
to
o
-------
Figure 23-4. Wind Rose for PRRI Sampling Days
to
SOUTH .-'
WIND SPEED
(Knots)
| | >= 22
^| 17 - 21
• 1-1 - 17
^| 7- 11
I I 4- 7
^| 2- 4
Cdlms: 9.88%
-------
23.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could
not be performed as ERG did not analyze VOCs at this site. A mobile tracer analysis could not
be performed as this site did not sample for SNMOC.
23.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population were obtained from Rhode Island Data
Control and the U.S. Census Bureau, and is summarized in Table 23-5. Table 23-5 also includes
a vehicle registration to county population ratio (vehicles per person). In addition, the population
within 10 miles of each site is presented. An estimate of 10-mile vehicle registration was
computed using the 10-mile population surrounding the monitors and the vehicle registration
ratio. Finally, Table 23-5 contains the average daily traffic information, which represents the
average number of vehicles passing the monitoring sites on the nearest roadway to each site on a
daily basis.
Observations gleaned from Table 23-5 include:
• Compared to other UATMP sites, PRRI's county population is in the middle of the
range, while its 10-mile population is in the highest third.
• Due to the low number of registered vehicles, the vehicle per person ratio is very low.
Consequently, the number of estimated vehicles within 10 miles is in the lower third
among UATMP sites.
• Daily traffic volume is also in the lower third of UATMP sites.
23.6 Trends Analysis
A trends analysis could not be performed for PRRI as this site has not participated in the
UATMP for three consecutive years.
23.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
PRRI and where the annual average concentrations could be calculated (refer to Section 3.3.5
23-12
-------
Table 23-5. Motor Vehicle Information for the Rhode Island Monitoring Site
Site
PRRI
2006 Estimated
County Population
635,596
Number of
Vehicles
Registered
142,334
Vehicles per Person
(Registration:
Population)
0.22
Population Within
10 Miles
685,230
Estimated 10 Mile
Vehicle
Ownership
153,449
Traffic Data
(Daily Average)
5,500
to
-------
regarding the definition of an annual average). Annual averages, theoretical cancer and
noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 23-6. Additionally,
the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA for the pollutants
that failed at least one screen at PRRI were retrieved and are presented in Table 23-6. The
NATA data are presented for the census tract where the monitoring site is located.
The census tract information for the Rhode Island monitoring site is as follows:
• PRRI is located in census tract 44007000400.
• The population for the census tract where the PRRI monitoring site is located was
3,660, which represents about 0.5 percent of Providence County's population in 2000.
The following observations can be made from Table 23-6:
• Both the NATA-modeled and annual average concentration for hexavalent chromium
was less than 0.01 |ig/m3.
• The NATA-modeled cancer risk (1.41 in-a-million) was greater than the annual
average-based cancer risk (0.33 in-a-million, respectively).
• Both noncancer hazard quotients were less than 0.01, suggesting very little risk for
noncancer health affects due to hexavalent chromium.
23.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 23-7 and 23-8 present a
risk-based assessment of the county-level emissions based on cancer and noncancer toxicity,
respectively. Table 23-7 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the hexavalent
chromium cancer risk (in-a-million) as calculated from the annual average. Table 23-8 identifies
the 10 pollutants with the highest emissions, noncancer toxicity-weighted emissions, and the
hexavalent chromium noncancer risk (HQ) as calculated from the annual average. The pollutants
in these tables are limited to those that have cancer and noncancer risk factors, respectively. As
a result, the highest emitted pollutants in the cancer table may not be the same as the noncancer
table, although the actual value of the emissions will be. Secondly, each site sampled for
23-14
-------
Table 23-6. Chronic Risk Summary for the Monitoring Site in Rhode Island
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk (HQ)
Providence, Rhode Island (PRRI) - Census Tract ID 44007000400
Hexavalent Chromium
0.012
0.0001
<0.01
1.41
<0.01
<0.01±<0.01
0.33
<0.01
to
-------
Table 23-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for PRRI
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(for Providence County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Providence County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for PRRI)
Cancer Risk
Pollutant (in-a-million)
Providence, Rhode Island - PRRI
Benzene
Formaldehyde
Tetrachloroethylene
Acetaldehyde
1,3 -Butadiene
Trichloroethylene
Dichloromethane
£>-Dichlorobenzene
Naphthalene
Nickel
310.24
178.17
93.14
52.50
42.18
41.73
30.23
13.64
8.60
4.58
Benzene
1,3 -Butadiene
Nickel
Hexavalent Chromium
Tetrachloroethylene
Lead
Cadmium
Naphthalene
Arsenic
/>-Dichlorobenzene
2.42E-03
1.27E-03
7.33E-04
5.86E-04
5.50E-04
4.03E-04
2.98E-04
2.93E-04
1.81E-04
1.50E-04
Hexavalent Chromium 0.33
to
-------
Table 23-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
forPRRI
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Providence County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Providence County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for PRRI)
Noncancer
Risk
Pollutant (HQ)
Providence, Rhode Island - PRRI
Toluene
Methyl 7er/-Butyl Ether
Xylenes
Methanol
Benzene
Formaldehyde
Ethylbenzene
Hexane
Tetrachloroethylene
Methyl Ethyl Ketone
815.33
600.89
551.52
328.64
310.24
178.17
130.72
110.63
93.14
76.85
Acrolein
Nickel
1,3 -Butadiene
Formaldehyde
Benzene
Cadmium
Cyanide
Acetaldehyde
Xylenes
Chlorine
427,471.34
70,466.67
21,091.64
18,180.44
10,341.31
8,282.30
7,872.55
5,833.75
5,515.18
4,567.50
Hexavalent Chromium <0.01
to
-------
specific types of pollutants. Therefore, the cancer and noncancer risk based on each site's annual
average is limited to those pollutants for which each respective site sampled. In addition, the highest
cancer and noncancer risks based on annual averages are limited to those pollutants failing at least
one screen.
The following observations can be made from Table 23-7:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor and also
had the highest cancer toxicity-weighted emissions for Providence County, Rhode Island.
• Six of the top 10 pollutants (benzene, tetrachloroethylene, 1,3 -butadiene, p-
dichlorobenzene, naphthalene, and nickel) appeared on both the highest emitted list and
the highest toxicity-weighted emissions list, indicating that most of the highest emitted
pollutants were also the most toxic.
• Hexavalent chromium, the only pollutant sampled at PRRI, had a low cancer risk based
on its annual average (0.33 in-a- million), but was identified as having the fourth highest
toxicity-weighted emissions in Providence County.
The following observations can be made from Table 23-8:
• Although toluene and methyl fert-butyl ether were the highest emitted pollutants with
noncancer risk factors, neither pollutant ranked in the top 10 based on toxicity-weighted
emissions.
• Instead, acrolein had the highest noncancer toxicity-weighted emissions; this pollutant
did not appear in the list of highest emitted pollutants.
• Hexavalent chromium did not rank among the top 10 highest emitted pollutants with
noncancer risk factors or the 10 highest noncancer toxicity-weighted emissions in
Providence County, and had a very low noncancer risk, based on the annual average for
PRRI.
Rhode Island Pollutant Summary
Hexavalent chromium was the only pollutant sampled for at PRRI. The pollutant failed six
percent of screens.
23-18
-------
24.0 Site in South Carolina
This section presents meteorological, concentration, and spatial trends for the UATMP
site in South Carolina (CHSC). This site is located in the Chesterfield area. Figure 24-1 is a
topographical map showing the monitoring site in its rural location. Figure 24-2 identifies point
source emission locations within 10 miles of this site that reported to the 2002 NEI for point
sources. CHSC is located near only two sources, located to the northeast and east of the site.
One of the facilities is involved in fuel combustion processes and the other is involved in surface
coating processes.
The town of Chesterfield is located in the NC/SC border, north of Florence. The area
boasts a temperate climate, typical of its southeast location. Winters tend to be mild and
snowfall is rare, while summers can be hot and humid, due in part to its proximity to the Atlantic
(http: //wkb wradi o. com/site/1 ocalitem s. htm).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the CHSC monitoring site is at Monroe Airport, Monroe, North Carolina (WBAN 53872).
Table 24-1 presents the average meteorological conditions of temperature (average maximum
and average), moisture (average dew point temperature, average wet-bulb temperature, and
average relative humidity), pressure (average sea level pressure), and wind information (average
scalar wind speed) for the entire year and on days samples were collected. Also included in
Table 24-1 is the 95 percent confidence interval for each parameter. As shown in Table 24-1,
average meteorological conditions on sampling days were representative of the average weather
conditions throughout the year.
24-1
-------
Figure 24-1. Chesterfield, South Carolina (CHSC) Monitoring Site
/
- ~ --.*'
\( .
- -I -:
I . )
>K! si-',-. \ l/ri - - .*""
mk^' r;-fl,
f •/
, ,, . \ f , \ i : .. - . %
^ ' \ yeV/ ^^ >r
4 .' S ,-'-iv-^-^r'~ - ..
.A\;.:-rv:^v
h^
-
*r ^—-^ ? ^ .•
-v-5^
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
24-2
-------
Figure 24-2. Facilities Located Within 10 Miles of CHSC
Bounty
Kersha*
County
Chesterfield
County
-tr-
Mote; Due to facility density and coUocaHcci, the total facilities
displayed may not represent alii facilities within the area of interest
Legend
-fa- CHSC UATMP site
10 mile radius
County boundary
Source Category Group (No. of Facilities)
F Fuel Combustion Industrial Facility (1)
s Surface Coating Processes Industrial Facility (1)
24-3
-------
Table 24-1. Average Meteorological Conditions near the Monitoring Site in South Carolina
Site
CHSC
WBAN
53872
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
72.02
±1.44
73.90
±3.27
Average
Temperature
(»F)
61.32
±1.39
63.12
±3.01
Average
Dew Point
Temperature
(°F)
47.72
±1.66
49.69
±3.40
Average
Wet Bulb
Temperature
(°F)
54.31
±1.32
55.91
±2.80
Average
Relative
Humidity
(%)
64.76
±1.36
65.59
±3.33
Average
Sea Level
Pressure
(mb)
1018.05
±0.64
1017.26
±1.48
Average
Scalar Wind
Speed
(kt)
4.58
±0.29
4.68
±0.70
to
-k
-------
24.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the South Carolina
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. Hexavalent chromium was the only
pollutant sampled for at CHSC.
The following observations are shown in Table 24-2
• None of the hexavalent chromium measured detections failed the screen.
• Hexavalent chromium will be considered a pollutant of interest for CHSC in order to
facilitate analysis.
Table 24-2. Comparison of Measured Concentrations and EPA Screening Values
for the South Carolina Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Chesterfield, South Carolina - CHSC
Hexavalent Chromium
0
27
0.00
0.00
0.00
24.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
24-5
-------
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 24-3. Annual averages are presented and discussed in further detail in later
sections.
The following observations are shown in Table 24-3:
• The daily average for CHSC for hexavalent chromium was 0.024 ± 0.006 ng/m3.
• Only spring and summer averages could be calculated due to the low number of
measured detections in winter and autumn. The spring and summer averages were
similar.
24.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for CHSC was evaluated using ATSDR short-
term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is defined
as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15 to 364
days. Its is useful to compare the preprocessed daily measurement to the short-term MRL and
REL factors, as well as compare the seasonal averages to the intermediate MRL. None of the
seasonal hexavalent chromium averages exceeded intermediate risk value. Acute risk could not
be assessed because hexavalent chromium has no acute risk factors.
24.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
24.4.1 Pearson Correlation Analysis
Table 24-4 presents the summary of Pearson correlation coefficients for hexavalent
chromium and select meteorological parameters for the CHSC monitoring site. (Please refer to
Section 3.1.6 for more information on Pearson correlations.) All of the correlations between
24-6
-------
Table 24-3. Daily and Seasonal Averages for the Pollutants of Interest for the South Carolina Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
Chesterfield, South Carolina - CHSC
Hexavalent Chromium
27
59
0.024
0.006
NR
NR
0.018
0.006
0.021
0.011
NR
NR
NR = Not reportable due to low number of measured detections.
to
-------
Table 24-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the South
Carolina Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Chesterfield, South Carolina - CHSC
Hexavalent Chromium
27
0.15
0.16
0.10
0.15
-0.08
0.15
-0.20
to
-^
oo
-------
hexavalent chromium and the pollutants of interest for CHSC were weak, indicating that
meteorology has little influence on concentrations of hexavalent chromium.
24.4.2 Composite Back Trajectory Analysis
Figure 24-3 is a composite back trajectory map for the CHSC monitoring site for the days
on which sampling occurred. Each line represents the 24-hour trajectory along which a parcel of
air traveled toward the monitoring site on a sampling day. Each concentric circle around the site
in Figure 24-3 represents 100 miles.
The following observations can be made from Figure 24-3:
• Back trajectories originated from a variety of directions at CHSC.
• The 24-hour airshed domain was somewhat large at CHSC, with trajectories
originating as far away as central Illinois (> 600 miles).
• Nearly 70 percent of the trajectories originated within 300 miles of the site; and 85
percent within 400 miles from the CHSC monitoring site.
24.4.3 Wind Rose Analysis
Hourly wind data from the Monroe Airport near the CHSC monitoring site were
uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces a
graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
about a 16-point compass, and uses different shading to represent wind speeds. Figure 24-4 is
the wind rose for the CHSC monitoring site on days that sampling occurred.
Observations from Figure 24-4 include:
• South-southwesterly to west-southwesterly winds account for over 27 percent of the
hourly wind observations near CHSC.
• Calm winds (<2 knots) were recorded for 34 percent of the observations. For wind
speeds greater than 2 knots, wind speeds in the 7 to 11 knot range were most
prevalent on sampling days.
24-9
-------
Figure 24-3. Composite Back Trajectory Map for CHSC
to
J^.
K^
o
-------
Figure 24-4. Wind Rose for CHSC Sampling Days
to
SOUTH .---
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
• 11 - 17
^| 7- 11
I I 4- 7
|^| 2- 4
Calm;: 34.01%
-------
24.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could not
be performed as ERG did not analyze for VOCs at this site. A mobile tracer analysis could not be
performed as this site did not sample for SNMOC.
24.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level population and vehicle registration information were obtained from the South
Carolina Department of Motor Vehicles and the U.S. Census Bureau, and is summarized in
Table 24-5. Table 24-5 also includes a vehicle registration to county population ratio (vehicles per
person). In addition, the population within 10 miles of each site is presented. An estimate of
10-mile vehicle registration was computed using the 10-mile population surrounding the monitors
and the vehicle registration ratio. Finally, Table 24-5 contains the average daily traffic information,
which represents the average number of vehicles passing the monitoring sites on the nearest roadway
to each site on a daily basis.
Observations gleaned from Table 24-5 include:
• Compared to other UATMP sites, CHSC's county population, vehicle registration, 10-
mile population, 10-mile ownership, and traffic count are in the bottom third of the
statistics.
• CHSC's person to vehicle ratio is in the top third.
• CHSC is located in a rural forested area.
24.6 Trends Analysis
A trends analysis could not be performed for CHSC as this site has not participated in the
UATMP for three consecutive years.
24.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
CHSC and where the annual average concentrations could be calculated (refer to Section 3.3.5
regarding the definition of an annual average). Annual averages, theoretical cancer and noncancer
24-12
-------
Table 24-5. Motor Vehicle Information for the South Carolina Monitoring Site
Site
CHSC
2006 Estimated
County Population
43,191
Number of
Vehicles
Registered
42,726
Vehicles per Person
(Registration:
Population)
0.99
Population
Within 10 Miles
37,525
Estimated
10 Mile Vehicle
Ownership
37,121
Traffic Data
(Daily
Average)
550
to
-------
risk, cancer UREs and/or noncancer RfCs are presented in Table 24-6. Additionally, the pollutants
of interest are bolded. Finally, data from EPA's 1999 NATA for the pollutants that failed at least
one screen at CHSC were retrieved and are presented in Table 24-6. The NATA data are presented
for the census tract where the monitoring site is located.
The census tract information for CHSC is as follows:
• The CHSC monitoring site is located in census tract 45025950800.
• The population for the census tract where the CHSC monitoring site is located was 2,492,
which represents about 5 percent of Chesterfield County's population in 2000.
The following observations can be made from Table 24-6:
• Both the NATA-modeled and annual average concentration for hexavalent chromium
were less than 0.01 |ig/m3.
• The NATA-modeled cancer risk (0.23 in-a-million) and the annual average-based cancer
risk (0.17 in-a-million) were very low. Additionally, both noncancer hazard quotients
were less than 0.01, suggesting very little risk for noncancer health affects due to
hexavalent chromium.
24.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 23-7 and 23-8 present a risk-
based assessment of the county-level emissions based on cancer and noncancer toxicity,
respectively. Table 23-7 presents the 10 pollutants with the highest emissions from the 2002 NEI,
the 10 pollutants with the highest toxicity-weighted emissions, and the hexavalent chromium cancer
risk (in-a-million) as calculated from the annual average. Table 23-8 identifies the 10 pollutants
with the highest emissions, noncancer toxicity-weighted emissions, and the hexavalent chromium
noncancer risk (HQ) as calculated from the annual average. The pollutants in these tables are
limited to those that have cancer and noncancer risk factors, respectively. As a result, the highest
emitted pollutants in the cancer table may not be the same as the noncancer table, although the actual
value of the emissions will be. Secondly, each site sampled for specific types of pollutants.
Therefore, the cancer and noncancer risk based on each site's annual average is limited to those
pollutants for which each respective site sampled. In addition, the highest cancer and noncancer
risks based on annual averages are limited to those pollutants failing at least one screen.
24-14
-------
Table 24-6. Chronic Risk Summary for the Monitoring Site in South Carolina
Pollutant
Cancer
URE
(Mg/m3)
Noncancer
RfC
(Mg/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(Hg/m3)
Cancer Risk
(in-a-million)
Noncancer
Risk (HQ)
Chesterfield, South Carolina (CHSC) - Census Tract ID 45025950800
Hexavalent Chromium
0.012
0.0001
0.01
0.23
0.01
0.01 ±0.01
0.17
0.01
to
-------
Table 24-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for CHSC
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(for Chesterfield County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Chesterfield County)
Pollutant
Cancer Toxicity
Weight
Top 10 Cancer Risks Based on
Annual Average Concentration
(for CHSC)
Cancer
Risk
(in-a-
Pollutant million)
Chesterfield, South Carolina - CHSC
Benzene
Formaldehyde
Dichloromethane
Acetaldehyde
1,3 -Butadiene
Trichloroethylene
Naphthalene
Tetrachloroethylene
Poly cyclic Organic Matter as 15 -PAH
/>-Dichlorobenzene
50.95
13.67
7.24
4.99
4.02
2.90
1.96
1.68
1.05
0.93
Benzene
Lead
1,3 -Butadiene
Naphthalene
Poly cyclic Organic Matter as 15 -PAH
Polycyclic Organic Matter as 7-PAH
Poly cyclic Organic Matter as non-15 PAH
Arsenic
Nickel
Acetaldehyde
3.97E-04
1.52E-04
1.21E-04
6.66E-05
5.76E-05
4.01E-05
3.04E-05
1.61E-05
1.31E-05
1.10E-05
Hexavalent Chromium 0.23
to
-------
Table 24-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for CHSC
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Chesterfield County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Chesterfield County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for CHSC)
Noncancer
Risk
Pollutant (HQ)
Chesterfield, South Carolina - CHSC
Toluene
Methyl Ethyl Ketone
Xylenes
Glycol Ethers
Benzene
Methanol
Ethylene Glycol
Ethylbenzene
Methyl Isobutyl Ketone
Hexane
133.62
130.71
114.21
80.86
50.95
33.95
32.03
23.74
20.05
18.85
Acrolein
Glycol Ethers
1,3 -Butadiene
Benzene
Formaldehyde
Cyanide
Nickel
Xylenes
Naphthalene
Acetaldehyde
41,997.99
4,043.10
2,010.56
1,698.30
1,395.09
1,390.34
1,255.70
1,142.14
653.02
554.60
Hexavalent Chromium <0.01
to
-------
The following observations can be made from Table 24-7:
• Benzene was the highest emitted pollutant with a cancer risk factor and had the highest
cancer toxicity-weighted emissions for Chesterfield County, South Carolina.
• Five of the top 10 pollutants (benzene, acetaldehyde, 1,3-butadiene, naphthalene, and
POM as 15-PAH) appeared on both the highest emitted list and the highest toxicity-
weighted emissions list, indicating that most of the highest emitted pollutants also tend to
be the most toxic.
• Hexavalent chromium, the only pollutant sampled for at CHSC, had a low cancer risk
based its annual average (0.23 in-a-million). This pollutant did not appear on either
highest emitted pollutant list or the highest toxicity-weighted emissions list.
The following observations can be made from Table 24-7:
• Toluene and methyl ethyl ketone were the highest emitted pollutants with noncancer risk
factors; however, neither pollutant ranked in the top 10 based on toxicity-weighted
emissions.
• Acrolein had the highest noncancer toxicity-weighted emissions, but did not appear in the
list of highest emitted pollutants.
• Hexavalent chromium did not rank in the top 10 highest emitted pollutants with
noncancer risk factors or the 10 highest noncancer toxicity-weighted emissions in
Chesterfield County, and had a very low noncancer risk, based on the annual average for
CHSC.
South Carolina Pollutant Summary
South Carolina sampled for hexavalent chromium only and no hexavalent chromium
measured detections failed screens.
24-18
-------
25.0 Sites in South Dakota
This section presents meteorological, concentration, and spatial trends for the UATMP
sites in South Dakota (CUSD and SFSD). One site is located in Custer, in western South
Dakota, south of Rapid City, and the other is located in Sioux Falls, in southeastern South
Dakota, respectively. Figures 25-1 and 25-2 are topographical maps showing the monitoring
sites in their urban and rural locations. Figures 25-3 and 25-4 identify point source emission
locations within 10 miles of the sites that reported to the 2002 NEI for point sources. Figure 25-
3 shows no point source emission sources located within 10 miles of the CUSD monitoring site.
Figure 25-4 shows that there are a few point sources located to the northwest of SFSD.
The Sioux Falls area has a continental climate, with cold winters, warm summers, and
often drastic day to day variations. Precipitation varies throughout the year, but is typically
sufficient for the springtime growing season. On average, a south wind blows in the summer and
a northwesterly wind blows in the winter. The weather in Custer is considered semi-arid
continental; annual precipitation is light. Warm summers and relatively mild winters are
characteristic of this area, thanks to the Black Hills to the west, allowing winters to be milder in
comparison to the rest of the state (Ruffner and Bair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the CUSD monitoring site is Custer County Airport (WBAN 94032); the closest weather
station to SFSD is Sioux Falls Joe Foss Field Airport (WBAN 14944). Table 25-1 presents
average meteorological conditions of temperature (average maximum and average), moisture
(average dew point temperature, average wet-bulb temperature, and average relative humidity),
pressure (average sea level pressure), and wind information (average scalar wind speed) for the
entire year and on days samples were collected. Also included in Table 25-1 is the 95 percent
confidence interval for each parameter. As shown in Table 25-1, average meteorological
conditions on sampling days were representative of average weather conditions throughout the
year.
25-1
-------
Figure 25-1. Custer, South Dakota (CUSD) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
25-2
-------
Figure 25-2. Sioux Falls, South Dakota (SFSD) Monitoring Site
r- 'L
|3gg
•
« •
Hi \ I
\ <
\ I
.
A/
5?
•
I
„ - .
•
In ...
"i-k -
^ \ - •'
V -^ \:
. -s<,X
^sS'T . /\
r '*o0 / W- / • \
M •• • i
ijgj
>
^ / i.
\ / 9>
M/
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
25-3
-------
Figure 25-3. Facilities Located Within 10 Miles of CUSD
Pennington
County
Custer
County
Note: Due to facility density artd collocation, the total facilities
displayed may not represent all facilities within the area of interest.
Legend
•& CUSD UATMP Site
10 mile radius
County boundary
"There were no facilities in the 2002 NEI within 10 miles of CUSD.
25-4
-------
Figure 25-4. Facilities Located Within 10 Miles of SFSD
Minnehaha
County
J
J
S
County /
Note: Due to facility density and collocation, the total facilities
displayed may not represent all facilities within the ares of interest.
Legend
<&• SFSD UATM P site
•." • 10 mite radius
| County boundary
Source Category Group (No. of Facilities)
* Automotive Repair, Services. & Parking (1)
c Chemicals & Allied Products Facility (1)
F Fuel Combustion Industrial Facility (1)
J Industrial Machinery & Equipment Facility (3)
s Surface Coating Processes Industrial Facility (1)
25-5
-------
Table 25-1. Average Meteorological Conditions near the Monitoring Sites in South Dakota
Site
CUSD
SFSD
WBAN
94032
14944
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(»F)
54.76
±2.02
54.18
±4.91
58.83
±2.14
59.87
±5.33
Average
Temperature
(OF)
44.27
±1.82
43.96
±4.36
48.97
±2.00
49.28
4.96
Average
Dew Point
Temperature
(°F)
26.97
±1.51
26.67
±3.59
38.07
±1.83
38.16
±4.48
Average
Wet Bulb
Temperature
(°F)
36.43
±1.45
36.16
±3.45
43.61
±1.76
43.71
±4.36
Average
Relative
Humidity
(%)
56.01
±1.56
55.91
±3.98
69.18
± 1.18
68.69
±2.44
Average
Sea Level
Pressure
(mb)
1014.58
±0.79
1014.90
±1.95
1015.44
±0.82
1015.89
± 1.88
Average Scalar
Wind Speed
(kt)
5.68
±0.23
5.82
±0.60
8.52
±0.39
8.00
±0.90
to
-------
25.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the South Dakota
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total screens. The South Dakota sites sampled for carbonyl
compounds, SNMOC, and VOC. Table 25-2 presents the pollutants that failed at least one
screen at the South Dakota monitoring sites.
Table 25-2. Comparison of Measured Concentration and EPA Screening Values
for the South Dakota Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Custer, South Dakota- CUSD
Benzene
Carbon Tetrachloride
Acetaldehyde
Acrolein
1,3 -Butadiene
Formaldehyde
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Acrylonitrile
£>-Dichlorobenzene
Hexachloro- 1 ,3 -butadiene
w-Hexane
Toluene
Trichloroethylene
Xylenes
1 ,2-Dichloroethane
Total
61
60
60
47
42
31
7
4
o
5
3
1
1
1
1
1
1
324
61
60
62
47
52
62
7
22
o
5
9
1
61
61
2
61
1
572
100.00
100.00
96.77
100.00
80.77
50.00
100.00
18.18
100.00
33.33
100.00
1.64
1.64
50.00
1.64
100.00
56.64
18.83
18.52
18.52
14.51
12.96
9.57
2.16
1.23
0.93
0.93
0.31
0.31
0.31
0.31
0.31
0.31
18.83
37.35
55.86
70.37
83.33
92.90
95.06
96.30
97.22
98.15
98.46
98.77
99.07
99.38
99.69
100.00
25-7
-------
Table 25-2. Comparison of Measured Concentration and EPA Screening Values
for the South Dakota Monitoring Sites (Continued)
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Sioux Falls, South Dakota - SFSD
Benzene
Acetaldehyde
Carbon Tetrachloride
Formaldehyde
Acrolein
1,3 -Butadiene
Acrylonitrile
Tetrachloroethylene
£>-Dichlorobenzene
1 ,2-Dichloroethane
Hexachloro- 1 ,3 -butadiene
Total
59
59
58
54
42
35
10
7
3
2
2
331
59
60
59
60
42
45
10
33
13
2
2
385
100.00
98.33
98.31
90.00
100.00
77.78
100.00
21.21
23.08
100.00
100.00
85.97
17.82
17.82
17.52
16.31
12.69
10.57
3.02
2.11
0.91
0.60
0.60
17.82
35.65
53.17
69.49
82.18
92.75
95.77
97.89
98.79
99.40
100.00
The following observations are shown in Table 25-2:
• Sixteen pollutants with a total of 324 measured concentrations failed the screen at
CUSD and 11 pollutants with a total of 331 measured concentrations failed the screen
at SFSD.
• The pollutants of interest varied by site, yet the following six pollutants contributed
to the top 95 percent of the total failed screens at each South Dakota monitoring site:
benzene, acetaldehyde, carbon tetrachloride, formaldehyde, 1,3-butadiene, and
acrolein.
• Of the six pollutants that were the same for both sites, two pollutants of interest
(benzene and acrolein) had 100 percent of their measured detections fail screens.
25.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
25-8
-------
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. The daily and seasonal average concentrations
are presented in Table 25-3. Annual averages are presented and discussed in further detail in
later sections.
The following observations for CUSD are shown in Table 25-3:
• Acetaldehyde had the highest daily average concentration by mass (1.25 ±0.16
|ig/m3), followed by formaldehyde (1.11 ± 0.15 |ig/m3) and acrolein (0.91 ± 0.16
|ig/m3).
• Acetaldehyde, formaldehyde, and benzene were detected in every sample collected at
CUSD.
• Seasonal averages for some of the pollutants of interest could not be calculated due to
the low number of measured detections.
• Benzene and 1,3-butadiene had high autumn averages for CUSD, but the relatively
high confidence intervals indicate that these averages were influenced by outliers.
• Formaldehyde tended to be higher in summer for CUSD.
The following observations for SFSD are shown in Table 25-3:
• Formaldehyde and acetaldehyde had the highest daily average concentrations by
mass (3.52 ± 0.73 |ig/m3 and3.30 ± 0.63 |ig/m3, respectively). Additionally, these
pollutants' daily averages were an order of magnitude higher than the daily averages
for other pollutants of interest.
• Acetaldehyde, benzene, carbon tetrachloride, and formaldehyde were detected in
every sample collected at SFSD.
• Seasonal averages for some of the pollutants of interest could not be calculated due to
the low number of measured detections at SFSD.
• Seasonal averages of many of the pollutants of interest at SFSD did not vary much,
although the summer seasonal average of formaldehyde was higher than its other
seasonal averages. Additionally, acetaldehyde was higher in summer and autumn.
25-9
-------
Table 25-3. Daily and Seasonal Averages for the Pollutants of Interest for the South Dakota Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Ug/m3)
Conf.
Int.
Spring
Avg
(Ug/m3)
Conf.
Int.
Summer
Avg
(Ug/m3)
Conf.
Int.
Autumn
Avg
(Ug/m3)
Conf.
Int.
Custer, South Dakota - CUSD
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Formaldehyde
1 , 1 ,2,2-Tetrachloroethane
62
47
61
52
60
62
7
62
61
61
61
61
62
61
1.25
0.91
0.89
0.15
0.59
1.11
0.13
0.16
0.16
0.44
0.13
0.05
0.15
0.04
1.11
0.34
0.84
0.10
0.45
0.77
NR
0.24
0.09
0.16
0.03
0.05
0.15
NR
1.05
NR
0.53
0.06
0.49
0.89
NR
0.20
NR
0.12
0.02
0.08
0.17
NR
1.33
0.90
0.46
0.04
0.71
1.60
NR
0.30
0.20
0.07
0.01
0.10
0.31
NR
1.53
1.22
1.73
0.32
0.68
1.21
NR
0.47
0.37
1.69
0.45
0.12
0.33
NR
Sioux Falls, South Dakota - SFSD
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Formaldehyde
60
42
10
59
45
59
60
60
59
59
59
59
59
60
3.30
0.71
0.55
0.59
0.05
0.62
3.52
0.63
0.10
0.20
0.05
0.01
0.05
0.73
1.94
0.41
NR
0.69
0.04
0.49
3.36
0.43
0.16
NR
0.09
0.01
0.09
2.12
1.69
NR
NR
0.48
NR
0.57
2.95
0.46
NR
NR
0.04
NR
0.07
0.96
5.85
0.84
NR
0.55
0.06
0.75
5.15
1.47
0.21
NR
0.12
0.01
0.10
0.91
3.97
0.70
NR
0.62
0.06
0.70
2.69
1.12
0.14
NR
0.11
0.01
0.10
0.54
to
NR = Not reportable due to low number of measured detections.
-------
25.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for the South Dakota monitoring sites was
evaluated using ATSDR short-term (acute) and intermediate MRL and California EPA acute
REL factors. Acute risk is defined as exposures from 1 to 14 days while intermediate risk is
defined as exposures from 15 to 364 days. It is useful to compare the preprocessed daily
measurements to the short-term MRL and REL factors, as well as compare seasonal averages to
the intermediate MRL. Of the pollutants with at least one failed screen, only acrolein exceeded
either the acute and intermediate risk values, and each site's non-chronic risk is summarized in
Table 25-4.
The following observations about acrolein are shown in Table 25-4:
• All of the acrolein measured detections at the South Dakota monitoring sites were
greater than the ATSDR acute value of 0.11 |ig/m3 and the California REL value of
0.19|ig/m3.
• The average detected concentration was 0.71 ± 0.10 |ig/m3 for SFSD and 0.91 ± 0.16
|ig/m3 for CUSD, which were both several times larger than either acute risk factor.
• With the exception of spring, the seasonal averages for acrolein could be calculated
for both sites. Winter averages of acrolein tended to be lower than other seasons for
the South Dakota sites.
• All the seasonal averages were significantly higher than the ATSDR intermediate risk
value.
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of
concentration and wind direction. For both South Dakota monitoring sites, only acrolein
concentrations exceeded the acute risk factors. Figures 25-5 and 25-6 are pollution roses for
acrolein at the South Dakota sites. As shown in Figures 25-5 and 25-6, and discussed above,
Observations gleaned from acrolein pollution roses include:
• All acrolein concentrations exceeded the acute risk factors, which are indicated by a
dashed line (CALEPA REL) and solid line (ATSDR MRL).
25-11
-------
Table 25-4. Non-Chronic Risk Summary for the South Dakota Monitoring Sites
Site
CUSD
SFSD
Method
TO-15
TO- 15
Pollutant
Acrolein
Acrolein
Daily Average
(ug/m3)
0.91 ±0.16
0.71 ±0.10
ATSDR
Short-term
MRL
(Ug/m3)
0.11
0.11
# of ATSDR
MRL
Exceedances
47
42
CAL EPA
REL Acute
(Ug/m3)
0.19
0.19
# of CAL
EPA REL
Exceedances
47
42
ATSDR
Intermediate-
term MRL
(Hg/m3)
0.09
0.09
Winter
Average
(Mg/m3)
0.34
±0.09
0.41
±0.16
Spring
Average
(Ug/m3)
NR
NR
Summer
Average
(Ug/m3)
0.90
±0.20
0.84
±0.21
Autumn
Average
(Ug/m3)
1.22
±0.37
0.70
±0.14
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
to
-------
Figure 25-5. Acrolein Pollution Rose for CUSD
to
3.5
3.0
2.5
2.0
1.5
| 1'°
0)
o
£
ra 0.5
1,0
1.5
2.0
2.5
3.0
3.5
A n
NW N
-
^
-
-
W • ^^ *-
• ' ^ ^ \^-
V A A v «-
* ^ * -
* •
-
-
-
sw s
3 NE
— CA EPA REL (0.19 |jg/m3)
— ATSDR MRL(0.11 M9/m3)
*
*,*•* »* E
* *
*
*
Dailv Ava Cone =0.91 +0.16 ua/m3 SE
4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0
Pollutant Concentration
1.5
2.0
2.5
3.0
3.5
4.0
-------
Figure 25-6. Acrolein Pollution Rose for SFSD
to
3.0
2.5
2.0
1.5
1.0
O
IB
2 0.5
.p
c
01
o
O 0.0
O
4-1
| 0.5
O
Q.
1.0
1.5
2.0
2.5
3.0
NW
w
sw
,
— CA EPA REL (0.19 |jg/m3)
— ATSDR MRL (0.1 1 |jg/m3)
N
NE
Dailv Ava Cone =0.71 ± 0. 1 0 ud/m3
SE
3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5
Pollutant Concentration
1.0
1.5
2.0
2.5
3.0
-------
• Figure 25-5 for CUSD shows that concentrations exceeding the acute risk factors
occurred with a variety of wind directions, although most frequently with winds from
the west. The highest concentrations of acrolein occurred with westerly and west-
southwesterly winds. Given that no point sources are located within 10 miles of the
CUSD site, acrolein concentrations may be attributable to mobile sources. The
monitoring site is located near the intersection of two major roadways in the area.
• Figure 25-6 for SFSD shows that concentrations exceeding the acute risk factors
occurred with a variety of wind directions, which is consistent with mobile source
emissions. Most point sources within 10 miles of the SFSD site were located towards
the northwest of the site. As Figure 25-2 shows, the SFSD site is located near major
roadways, such as 1-229 and Highway 42.
25.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
25.4.1 Pearson Correlation Analysis
Table 25-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the South Dakota monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for CUSD from Table 25-5:
• Strong positive correlations were calculated for formaldehyde and carbon
tetrachloride and maximum, average, dew point, and wet bulb temperatures. This
indicates that increasing temperature and humidity levels correlate to increasing
concentrations of these pollutants.
• A few strong correlations were calculated for 1,1,2,2-tetrachloroethane. However,
the low number of measured detections may skew the correlations.
• Most of the remaining correlations were weak at CUSD.
25-15
-------
Table 25-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the South
Dakota Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Custer, South Dakota- CUSD
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Formaldehyde
1 , 1 ,2,2-Tetrachloroethane
62
47
61
52
60
62
7
0.08
0.27
-0.18
-0.17
0.54
0.58
-0.28
0.03
0.26
-0.20
-0.17
0.56
0.55
-0.38
-0.05
0.24
-0.23
-0.19
0.56
0.45
-0.52
-0.01
0.26
-0.22
-0.18
0.59
0.52
-0.42
-0.11
-0.04
-0.05
-0.02
-0.14
-0.21
-0.20
0.06
-0.24
-0.09
-0.13
-0.14
-0.05
0.52
-0.24
-0.19
0.07
0.11
-0.28
-0.29
-0.15
Sioux Falls, South Dakota- SFSD
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Formaldehyde
60
42
10
59
45
59
60
0.39
0.28
0.72
-0.09
-0.09
0.57
0.19
0.38
0.25
0.75
-0.18
-0.15
0.54
0.21
0.33
0.26
0.76
-0.17
-0.13
0.53
0.19
0.36
0.25
0.76
-0.18
-0.14
0.54
0.20
-0.30
0.02
0.35
0.11
0.14
-0.14
-0.14
0.07
-0.12
-0.52
-0.01
0.12
-0.24
-0.02
-0.37
-0.07
0.05
-0.36
-0.37
-0.22
-0.07
to
-------
The following observations are gathered for SFSD from Table 25-5:
• Similar to CUSD, strong positive correlations were calculated for carbon
tetrachloride and maximum, average, dew point, and wet bulb temperatures. This
indicates that increasing temperature and humidity levels correlate to increasing
concentrations of these pollutants.
• Acrylonitrile also exhibited strong positive correlations with these parameters.
However, the low number of measured detections may skew the correlations.
• Most of the remaining correlations were weak.
25.4.2 Composite Back Trajectory Analysis
Figures 25-7 and 25-8 are composite back trajectory maps for the South Dakota
monitoring sites for the days on which sampling occurred. Each line represents the 24-hour
trajectory along which a parcel of air traveled toward the monitoring site on a sampling day.
Each concentric circle around the site represents 100 miles.
The following observations can be made from Figure 25-7:
• Back trajectories originated predominantly from all directions except the north and
northeast at CUSD.
• The 24-hour airshed domain was somewhat large at CUSD, with trajectories
originating as far away as Alberta, Canada, nearly 800 miles away.
• The majority of the trajectories originated within 500 miles of the site.
The following observations can be made from Figure 25-8:
• Back trajectories originated from a variety of directions around SFSD, although
predominantly from the south, northwest, and north.
• The 24-hour airshed domain was larger at SFSD, with the longest trajectory
originating over 900 miles away. However, most of the trajectories originated within
500 miles of the site.
25.4.3 Wind Rose Analysis
Hourly wind data from the Custer County and Foss Field Airports were uploaded into a
wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces a graphical wind
25-17
-------
Figure 25-7. Composite Back Trajectory Map for CUSD
to
v\
I
K^
oo
-------
Figure 25-8. Composite Back Trajectory Map for SFSD
to
v\
I
K^
VO
-------
rose from the wind data. A wind rose shows the frequency of wind directions about a 16-point
compass, and uses different shading to represent wind speeds. Figures 25-9 and 25-10 are the
wind roses for the South Dakota monitoring sites on days that sampling occurred.
Observations from Figure 25-9 for CUSD include:
• Hourly winds were predominantly out of the west (15 percent of observations), west-
southwest (9 percent), and west-northwest (9 percent) on days that samples were
collected near CUSD.
• Calm winds (< 2 knots) were recorded for 17 percent of the observations.
• Wind speeds ranging from 7 to 11 knots were recorded most often.
• The strongest winds tended to have a westerly component.
Observations from Figure 25-10 for SFSD include:
• Hourly winds were predominantly out of south (11 percent of observations), east (8
percent), and north-northwest (8 percent) on days that samples were collected near
SFSD.
• Calm winds were observed for 14 percent of the observations, while wind speeds of 7
to 11 knots were recorded most frequently.
• Wind speeds greater than 22 knots were recorded most frequently with a northerly
component.
25.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; BTEX analysis; and
acetylene-ethylene mobile tracer analysis.
25.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Custer and Minnehaha Counties were
obtained from the South Dakota Department of Revenue and Regulation and the U.S. Census
25-20
-------
Figure 25-9. Wind Rose for CUSD Sampling Days
to
v\
to
SOUTH --'
WIND SPEED
(Knots)
I | >=22
I I 17 - 21
• 11 - 17
^| 7- 11
^| 2- 4
Calms:
-------
Figure 25-10. Wind Rose for SFSD Sampling Days
to
to
to
SOUTH .--•
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
• 11 - 17
^| 7- 11
I I -q- 7
^| 2- 4
Calms: 13.73%
-------
Bureau, and are summarized in Table 25-6. Table 25-6 also includes a vehicle registration to
county population ratio (vehicles per person). In addition, the population within 10 miles of each
site is presented. An estimation of 10-mile vehicle registration was computed using the 10-mile
population surrounding the monitor and the vehicle registration ratio. Finally, Table 25-6
contains the average daily traffic information, which represents the average number of vehicles
passing the monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 25-6 include:
• The CUSD monitoring site has a significantly lower county and 10-mile population
than the SFSD site, as well as a significantly lower county and estimated 10-mile
vehicle ownership.
• CUSD has the lowest county and 10-mile population, the second lowest county
vehicle registration, and the lowest estimated 10-mile vehicle ownership of all
participating UATMP sites. However, the CUSD site has the highest registration-
population ratio.
• SFSD is in the bottom third of UATMP sites for the population and vehicle
registration statics.
• While the daily traffic flow near CUSD is significantly lower than at SFSD, these two
sites' daily traffic counts are both on the low end compared to other UATMP sites.
25.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compared them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• For both South Dakota sites, the benzene-ethylbenzene ratio was higher than the
xylenes-ethylbenzene ratio, which is the opposite of the roadside study.
25-23
-------
Table 25-6. Motor Vehicle Information for the South Dakota Monitoring Sites
Site
CUSD
SFSD
2006 Estimated
County
Population
7,944
163,281
Number of
Vehicles
Registered
14,191
202,696
Vehicles per Person
(Registration:
Population)
1.79
1.24
Population
Within
10 Miles
5,492
161,598
Estimated 10 Mile
Vehicle Ownership
9,811
200,607
Traffic Data
(Daily Average)
1,940
4,320
to
-------
• For CUSD, the benzene-ethylbenzene ratio exceeded the toluene-ethylbenzene ratio
(6.42 ± 0.66 and 6.00 ± 0.51, respectively).
• At SFSD, the toluene-ethylbenzene ratio (10.70 ± 2.32) was significantly higher than
that of the roadside study (5.85).
25.5.3 Mobile Tracer Analysis
As previously stated, CUSD and SFSD sampled for SNMOC in addition to VOC.
Acetylene is a pollutant that is primarily emitted from mobile sources, while ethylene is emitted
from mobile sources, petroleum refining facilities, and natural gas distribution facilities. Tunnel
studies conducted on mobile sources have found that concentrations of ethylene and acetylene
are typically present in a 1.7 to 1 ratio. (For more information, please refer to Section 3.2.1.3.)
Table 3-11 shows:
• CUSD's ethylene-acetylene ratio (1.43) is closer to the 1.7 ratio, although still lower.
• SFSD's ethylene-acetylene ratio (1.22) was lower than the 1.7 ratio and lower than
CUSD's ratio.
• These ratios suggest that while mobile sources may be influencing the air quality at
the South Dakota monitoring sites, there may also be atmospheric chemical processes
affecting the quantities of ethylene in these areas. Known sinks of ethylene include
reactions with ozone, as well as soil (NLMb).
25.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. The
CUSD monitoring site has participated in the UATMP since 2002. Figures 25-11 and 25-12
present the trends analysis for formaldehyde, benzene, and 1,3-butadiene for CUSD and SFSD,
respectively.
The following observations can be made from Figure 25-11 for CUSD:
• Formaldehyde concentrations have decreased since 2002.
• Similarly, 1,3-butadiene concentrations appear to decrease over the four year period
prior to 2006, but the large confidence intervals in 2002 and 2006 indicate that the
decrease is not statistically significant.
25-25
-------
Figure 25-11. Comparison of the Yearly Averages for the CUSD Monitoring Site
to
v\
to
t
•3 C
•3
* ic
ntration (
r>
o c
8 '
o
o
a)
m 1 ^
(1)
•1
n *!
-r
— ± —
^_
2002
m.
3-Butadiene
-r
2003
^r
T
T
T
r-J Z . I ~^~
2004 2005 2006
Year
• Benzene D Formaldehyde
-------
• Benzene concentrations have not changed significantly since 2002 at CUSD,
although the large confidence interval in 2006 shows that outliers are likely affecting
the average.
The following observations can be made from Figure 25-12 for SFSD:
• Carbonyl compounds were not sampled for at SFSD until 2002, as indicated in
Figure 25-12. The large confidence interval, represented by the error bars in 2002,
indicates that the formaldehyde concentration may have been driven upward by a few
outliers, which makes it difficult to determine if formaldehyde concentrations
actually decreased from 2002 to 2003. Taking confidence intervals into account, it
appears that formaldehyde concentrations have remained roughly the same since
2003.
• The 1,3-butadiene concentration was highest in 2002, similar to formaldehyde, but
again, the high confidence interval indicates that the 1,3-butadiene concentration may
have been influenced by a few outliers. In 2004, 1,3-butadiene was detected only
once at SFSD, as the absence of a confidence interval indicates. Overall, 1,3-
butadiene concentrations seem to be decreasing slightly.
• Benzene concentrations have not changed significantly since 2000.
25.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the South Dakota sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 25-7.
Additionally, the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA were
retrieved and are also presented in Table 25-7. The NATA data are presented for the census tract
where the monitoring site is located.
The census tract information for the South Dakota sites is as follows:
• The census tract for CUSD is 46033995200, which had a population of 2,758, which
represents approximately 37.9 percent of the Custer County population in 2000.
• The census tract for SFSD is 46099001802, which had a population of 7,498, which
also represents approximately 5.1 percent of the county population in 2000.
25-27
-------
Figure 25-12. Comparison of the Yearly Averages for the SFSD Monitoring Site
to
to
oo
»
7
5 R
a.
_o.
c
O
'S c.
oncentra
i.
nj
i_
> ^
o
1 _
I I I I i • 1 1
2000 2001
• 1,3-Butadiene
I
1
2002
j
|— l
J-
. rH r^- i— , —
2003 2004 2005 2006
Year
• Benzene D Formaldehyde
-------
Table 25-7. Chronic Risk Summary for the Monitoring Sites in South Dakota
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
Oig/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 TJATMP
Annual
Average
(jig/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk
(HQ)
Custer, South Dakota (CUSD) - Census Tract ID 46033995200
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
/>-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
w-Hexane
1,1,2 ,2-Tetrachloroethane
Tetrachloroethylene
Toluene
Trichloroethylene
Xylenes
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
0.000026
5.5E-09
0.000022
NR
0.000058
0.0000059
NR
0.000002
NR
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
2.4
0.0098
0.09
0.2
NR
0.27
0.4
0.6
0.1
0.43
0.03
<0.01
0.26
0.01
0.21
<0.01
<0.01
0.31
<0.01
0.02
<0.01
<0.01
0.12
0.03
0.21
0.95
NR
0.01
2.07
0.39
3.11
0.01
<0.01
0.01
0.03
NR
O.01
0.01
NR
0.07
NR
0.05
1.52
O.01
0.01
0.01
0.01
O.01
O.01
0.03
O.01
0.01
NR
O.01
0.01
O.01
0.01
1.25 ±0.16
0.73 ±0.15
0.06 ±O.01
0.89 ±0.44
0.13±0.11
0.58 ±0.05
0.03 ±0.01
0.03 ± O.01
1.11±0.15
0.07 ±O.01
1.23 ±0.95
0.05 ±0.01
0.08 ±0.03
1.85 ±1.78
0.04 ± 0.02
2.07 ±1.48
2.75
NR
4.31
6.97
3.92
8.72
0.31
0.81
0.01
1.58
NR
3.14
0.45
NR
0.08
NR
0.14
36.65
0.03
0.03
0.07
0.01
O.01
O.01
0.11
O.01
0.01
NR
O.01
0.01
O.01
0.02
Sioux Falls, South Dakota (SFSD) - Census Tract ID 46099001802
Acetaldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
0.000026
5.5E-09
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
2.4
0.0098
0.68
0.02
<0.01
0.69
0.06
0.21
0.02
0.03
0.80
1.50
NR
0.02
5.41
1.82
3.12
0.17
0.67
0.01
0.08
1.21
O.01
0.02
0.03
0.01
0.01
O.01
0.08
3.30 ±0.63
0.54 ±0.10
0.14 ±0.06
0.59 ±0.05
0.05 ±O.01
0.62 ±0.05
0.03 ±0.01
0.03 ± O.01
3.52 ±0.73
7.27
NR
9.85
4.60
1.49
9.25
0.35
0.80
0.02
0.37
27.18
0.07
0.02
0.02
0.02
0.01
O.01
0.36
to
to
VO
-------
Table 25-7. Chronic Risk Summary for the Monitoring Sites in South Dakota (Continued)
Pollutant
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
Cancer
URE
Oig/m3)
0.000022
0.0000059
Noncancer
RfC
Oig/m3)
0.09
0.27
1999 NATA
Modeled
Concentration
(Hg/m3)
<0.01
0.09
Cancer Risk
(in-a-
million)
0.03
0.51
Noncancer
Risk (HQ)
<0.01
<0.01
2006 UATMP
Annual
Average
(Hg/m3)
0.07 ±0.01
0.08 ±0.02
Cancer
Risk (in-a-
million)
1.63
0.50
Noncancer
Risk
(HQ)
<0.01
<0.01
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
to
(^
i
OJ
o
-------
The following observations can be made for CUSD from Table 25-7:
• Xylenes and toluene had the highest annual averages by mass concentration for
CUSD. But neither of these pollutants have cancer risk factors.
• Carbon tetrachloride and benzene had both the highest NATA-modeled and annual
average-based cancer risks for CUSD, although the cancer risks based on the annual
averages were more than twice the NATA-modeled risk.
• Acrolein had the highest NATA-modeled and annual average-based noncancer risk
for CUSD, although the annual average-based HQ (36.65) was significantly higher
than the NATA-modeled HQ (1.52).
The following observations can be made for SFSD from Table 25-7:
• Acetaldehyde and formaldehyde's annual averages for SFSD were an order of
magnitude higher than any of the other pollutants of interest's annual averages.
These two pollutants also have some of the highest NATA-modeled concentrations,
although they were significantly lower than the annual averages.
• While acrylonitrile had the highest annual average-based cancer risk (9.85 in-a-
million) for SFSD, its NATA-modeled risk was two orders of magnitude lower (0.02
in-a-million).
• Benzene had the highest NATA-modeled cancer risk for SFSD, and its modeled
concentration and risk were very similar to the actual average and associated risk for
2006.
• Acrolein had the highest NATA-modeled and annual average-based noncancer risk
for SFSD, although the annual average-based HQ (27.18) was significantly higher
than the NATA-modeled HQ (1.21).
25.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 25-8 and 25-9 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 25-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 25-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
25-31
-------
Table 25-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in South Dakota
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer Risk
(in-a-
million)
Custer, South Dakota - CUSD - Custer County
Benzene
Formaldehyde
Acetaldehyde
Tetrachloroethylene
1,3 -Butadiene
Dichloromethane
Naphthalene
Poly cyclic Organic Matter as 15 -PAH
£>-Dichlorobenzene
Polycyclic Organic Matter as 7-PAH
13.77
4.91
2.25
1.58
1.10
0.57
0.45
0.36
0.16
0.07
Benzene
1,3 -Butadiene
Polycyclic Organic Matter as 15-PAH
Lead
Naphthalene
Polycyclic Organic Matter as 7-PAH
Polycyclic Organic Matter as non-15 PAH
Tetrachloroethylene
Acetaldehyde
£>-Dichlorobenzene
1.07E-04
3.30E-05
1.96E-05
1.56E-05
1.52E-05
1.26E-05
1.06E-05
9.31E-06
4.95E-06
1.77E-06
Carbon Tetrachloride
Benzene
Acrylonitrile
1,3 -Butadiene
1 , 1 ,2,2-Tetrachloroethane
Acetaldehyde
Hexachloro- 1 , 3 -butadiene
1 ,2-Dichloroethane
Tetrachloroethylene
£>-Dichlorobenzene
8.72
6.97
4.31
3.92
3.14
2.75
1.58
0.81
0.45
0.31
Sioux Falls, South Dakota - SFSD - Minnehaha County
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Tetrachloroethylene
Naphthalene
£>-Dichlorobenzene
Polycyclic Organic Matter as 15 -PAH
Trichloroethylene
132.45
53.88
24.45
12.17
11.98
6.04
4.62
3.27
2.46
1.05
Benzene
Lead
1,3 -Butadiene
Naphthalene
Polycyclic Organic Matter as 15-PAH
Arsenic
Polycyclic Organic Matter as non-15 PAH
Polycyclic Organic Matter as 7-PAH
Acetaldehyde
Ethylene Oxide
1.03E-03
3.98E-04
3.65E-04
1.57E-04
1.35E-04
1.22E-04
8.45E-05
6.54E-05
5.38E-05
3.77E-05
Acrylonitrile
Carbon Tetrachloride
Acetaldehyde
Benzene
Hexachloro- 1 , 3 -butadiene
1,3 -Butadiene
1 ,2-Dichloroethane
Tetrachloroethylene
£>-Dichlorobenzene
Formaldehyde
9.85
9.25
7.27
4.60
1.63
1.49
0.80
0.50
0.35
0.02
to
to
-------
Table 25-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in South Dakota
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk
(HQ)
Sioux Falls, South Dakota - SFSD - Minnehaha County
Toluene
Xylenes
Benzene
Formaldehyde
Ethylbenzene
w-Hexane
Methanol
Acetaldehyde
Styrene
Tetrachloroethylene
30.33
20.11
13.77
4.91
4.80
4.00
2.50
2.25
1.71
1.58
Acrolein
1,3 -Butadiene
Formaldehyde
Benzene
Cyanide
Acetaldehyde
Xylenes
Naphthalene
Toluene
Hydrochloric Acid
14,131.59
549.45
501.10
458.93
292.55
250.03
201.07
148.53
75.82
31.03
Acrolein
Acetaldehyde
Formaldehyde
1,3 -Butadiene
Acrylonitrile
Benzene
Xylenes
Carbon Tetrachloride
w-Hexane
Toluene
36.65
0.14
0.11
0.07
0.03
0.03
0.02
0.01
0.01
<0.01
Sioux Falls, South Dakota - SFSD - Minnehaha County
Toluene
Xylenes
Benzene
Methanol
Hydrochloric Acid
Formaldehyde
Ethylbenzene
w-Hexane
Methyl Ethyl Ketone
Styrene
318.26
235.83
132.45
85.68
63.23
53.88
46.98
40.28
37.81
28.27
Acrolein
1,3 -Butadiene
Formaldehyde
Benzene
Hydrochloric Acid
Acetaldehyde
Xylenes
Cyanide
Naphthalene
Nickel
146,524.06
6,086.91
5,497.45
4,415.13
3,161.30
2,716.33
2,358.33
1,874.27
1,541.21
1,447.07
Acrolein
Acetaldehyde
Formaldehyde
Acrylonitrile
1,3 -Butadiene
Benzene
Carbon Tetrachloride
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
/>-Dichlorobenzene
27.18
0.37
0.36
0.07
0.02
0.02
0.02
<0.01
0.01
0.01
to
-------
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. The South Dakota sites sampled for VOC, SNMOC, and carbonyls. In
addition, the highest cancer and noncancer risks based on annual averages are limited to those
pollutants failing at least one screen.
The following observations can be made from Table 25-8:
• Benzene was the highest emitted pollutant with a cancer risk factor, had the highest
cancer toxicity-weighted emissions, and had the second highest and fourth highest
cancer risk based on the 2006 annual average for CUSD and SFSD, respectively.
• Carbon tetrachloride had the highest and second highest cancer risk based on the
2006 annual averages for CUSD and SFSD, yet this pollutant was neither one of the
highest emitted nor one of the most toxic in Custer and Minnehaha Counties based on
the 2002 NEI emission inventory.
• Acrylonitrile had the highest cancer risk for SFSD and the third highest cancer risk
for CUSD, although this pollutant, like carbon tetrachloride, was neither one of the
highest emitted nor one of the most toxic.
The following observations can be made from Table 25-9:
• Toluene and xylenes were the highest emitted pollutants with noncancer risk factors
in both Custer and Minnehaha Counties.
• These pollutants rank seventh and ninth, respectively, for noncancer toxicity-
weighted emissions for Custer County, and seventh and tenth, respectively, for
noncancer risk for CUSD.
• Xylenes ranked seventh in Minnehaha County, but toluene did not make the top 10
toxicity-weighted emissions. Neither xylenes nor toluene made the top 10 list for
noncancer risk for SFSD.
• Acrolein had the highest noncancer toxicity-weighted emissions in both Custer and
Minnehaha Counties, and had the highest noncancer risks based on the 2006 annual
average for both sites, but did not appear in the list of highest emitted pollutants.
25-34
-------
South Dakota Pollutant Summary
• The pollutants of interest common to each of the South Dakota sites were acetaldehyde,
acrolein, benzene, 1,3-butadiene, carbon tetrachloride, and formaldehyde.
• Formaldehyde and acetaldehyde had the highest daily averages for CUSD and SFSD.
• Acrolein exceeded the short-term risk factors at both South Dakota sites.
• A comparison of formaldehyde, benzene and 1,3-butadiene concentrations for all years of
UATMP participation shows that concentrations of formaldehyde have been decreasing
at CUSD since 2002, while remaining steady at SFSD.
25-35
-------
26.0 Sites in Tennessee
This section presents meteorological, concentration, and spatial trends for the UATMP
sites in Tennessee (LDTN and MSTN). Both sites are located southwest of Knoxville in
Loudon. Figures 26-1 and 26-2 are topographical maps showing the monitoring sites in their
urban and rural locations. Figures 26-3 identifies point source emission locations within 10
miles of these sites as reported to the 2002 NEI for point sources. The LDTN and MSTN sites
have approximately two dozen point sources nearby and several of these are involved in waste
treatment and disposal, polymer and resin production, or fuel combustion processes.
Loudon is located to the southwest of Knoxville. The Tennessee River runs through
town, influencing the areas weather by moderating temperatures and affecting wind patterns.
The Appalachian Mountains lie to the east. The area has ample rainfall year-round and, like
Nashville, experiences all four seasons (Ruffner and Bair, 1987 and
http://www.blueshoenashville.com/weather.html).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the monitoring sites is the Knoxville McGhee-Tyson Airport (WBAN 03894). Table 26-1
presents the average meteorological conditions of temperature (average maximum and average),
moisture (average dew point temperature, average wet-bulb temperature, and average relative
humidity), pressure (average sea level pressure), and wind information (average scalar wind
speed) for the entire year and on days samples were collected. Also included in Table 26-1 is the
95 percent confidence interval for each parameter. As shown in Table 26-1, average
meteorological conditions on sampling days were representative of average weather conditions
throughout the year.
26.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Michigan
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
26-1
-------
Figure 26-1. Loudon, Tennessee (LDTN) Monitoring Site
v:/^w
.•v:^.;.,'-
--v>w
-
4
•-.'••'
-
!• . "vj j ' .
*-
Source: USGS 7.5 Minute Series. Map Scale: 1:25,000.
26-2
-------
Figure 26-2. Loudon, Tennessee (MSTN) Monitoring Site
msw
-v:: -
v
~' '
J' ifffff^vf'ir^Sf'-.
/ f v ' ; ,'' '•' ',
Source: USGS 7.5 Minute Series. Map Scale: 1:25,000.
26-2
-------
Figure 26-3. Facilities Located Within 10 Miles of LDTN and MSTN
Knox
County
Roane
County
•j , Bairn!
• \ County
fi '. F
Y
*'.
Loiidoo
County
MOT roe
County
Mote; Due to facility density and collocation, the total facilities
displaced may not represent all facilities within the area of interest.
•jit LDTN UATMP site
•jlr MSTN UATMP site
• • 10 mile radius
| County boundary
Source Category Group (No. of Facilities)
c Chemicals & Allied Products Facility (1)
F Fuel Combustion Industrial Facility (6)
•»• Integrated Iron & Steel Manufacturing Facility (1)
\ Non-ferrous Metals Processing Industrial Facility (1)
v Polymers & Resins Production Industrial Facility (4)
Y Rubber & Miscellaneous Plastic Products Facility (1)
u Stone, Clay. Glass, & Concrete Products (2)
S Surface Coating Processes Industrial Facility (1 )
! Waste Treatment & Disposal Industrial Facility (4}
26-4
-------
Table 26-1. Average Meteorological Conditions near the Monitoring Sites in Tennessee
Site
LDTN
MSTN
WBAN
13891
13891
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
<°F)
69.95
±1.58
70.86
±3.83
69.95
±1.58
72.56
±3.77
Average
Temperature
<°F)
59.78
±1.52
60.74
±3.55
59.78
±1.52
62.34
±3.51
Average
Dew Point
Temperature
<°F)
47.89
±1.62
49.29
±3.50
47.89
±1.62
50.45
±3.72
Average
Wet Bulb
Temperature
<°F)
53.50
±1.42
54.50
±3.14
53.50
±1.42
55.85
±3.18
Average
Relative
Humidity
(%)
67.91
±1.19
69.46
±3.30
67.91
±1.19
68.59
±3.37
Average
Sea Level
Pressure
(mb)
1017.32
±0.60
1016.46
±1.43
1017.32
±0.60
1016.89
±1.33
Average
Scalar
Wind Speed
(kt)
5.46
±0.30
6.00
±0.81
5.46
±0.30
5.52
±0.75
to
I
-------
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total screens. The Tennessee sites sampled for carbonyls
compounds and VOC only. Table 26-2 presents the pollutants that failed at least one screen at
the Tennessee monitoring sites.
Table 26-2. Comparison of Measured Concentrations and EPA Screening Values
for the Tennessee Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Loudon, Tennessee - LDTN
Acetaldehyde
Benzene
Carbon Tetrachloride
Formaldehyde
Acrolein
1,3 -Butadiene
£>-Dichlorobenzene
Hexachloro- 1 , 3 -butadiene
Tetrachloroethylene
Acrylonitrile
1 , 1 ,2,2-Tetrachloroethane
Chloromethylbenzene
Total
55
55
55
49
48
39
35
5
2
2
1
1
347
56
55
55
56
48
48
51
5
27
2
1
1
405
98.21
100.00
100.00
87.50
100.00
81.25
68.63
100.00
7.41
100.00
100.00
100.00
85.68
15.85
15.85
15.85
14.12
13.83
11.24
10.09
1.44
0.58
0.58
0.29
0.29
15.85
31.70
47.55
61.67
75.50
86.74
96.83
98.27
98.85
99.42
99.71
100.00
Loudon, Tennessee - MSTN
Acetaldehyde
Benzene
Carbon Tetrachloride
Formaldehyde
Acrolein
£>-Dichlorobenzene
1,3 -Butadiene
Acrylonitrile
Tetrachloroethylene
Total
50
49
49
44
44
36
26
5
3
306
51
49
49
51
44
47
40
5
29
365
98.04
100.00
100.00
86.27
100.00
76.60
65.00
100.00
10.34
83.84
16.34
16.01
16.01
14.38
14.38
11.76
8.50
1.63
0.98
16.34
32.35
48.37
62.75
77.12
88.89
97.39
99.02
100.00
26-6
-------
The following observations are shown in Table 26-2:
• Twelve 12 pollutants failed at least one screen at LDTN and a total of 347 measured
concentrations failed screens.
• Nine pollutants failed at least one screen at MSTN and a total of 306 measured
concentrations failed screens.
• The same seven pollutants contributed to 95 percent of the total failed screens for both
Tennessee monitoring sites: acetaldehyde, acrolein, benzene, 1,3-butadiene, carbon
tetrachloride, formaldehyde, and/>-dichlorobenzene.
• Acrolein, benzene, and carbon tetrachloride, concentrations failed 100 percent of screens
at each site.
26.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections andl/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. The daily and seasonal average concentrations
are presented in Table 26-3. Annual averages are presented and discussed in further detail in
later sections.
The following observations for LDTN are shown in Table 26-3:
• Acetaldehyde, benzene, carbon tetrachloride, and formaldehyde were detected in
every sample collected at the Tennessee monitoring sites.
• Formaldehyde had the highest average concentration by mass (2.58 ± 0.47 jug/m3) for
LDTN, followed by acetaldehyde (2.21 ± 0.32 //g/m3).
26-7
-------
Table 26-3. Daily and Seasonal Averages for the Pollutants of Interest for the Tennessee Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Hg/m3)
Conf.
Int.
Autumn
Avg
(Hg/m3)
Conf.
Int.
Loudon, Tennessee - LDTN
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
56
48
55
48
55
51
56
56
55
55
55
55
55
56
2.21
0.64
1.02
0.07
0.65
0.12
2.58
0.32
0.10
0.12
0.01
0.06
0.02
0.47
1.83
0.64
1.05
0.07
0.53
0.14
1.26
0.75
0.24
0.20
0.02
0.04
0.05
0.28
2.48
0.46
0.99
0.05
0.54
0.09
2.39
0.59
0.17
0.17
0.02
0.05
0.02
0.71
2.63
0.72
1.07
0.05
0.83
0.13
4.83
0.46
0.15
0.26
0.02
0.13
0.02
0.74
1.76
0.46
0.97
0.07
0.75
0.09
1.55
0.61
0.16
0.29
0.03
0.13
0.03
0.30
Loudon, Tennessee - MSTN
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
51
44
49
40
49
47
51
51
49
49
49
49
49
51
1.26
1.00
0.87
0.06
0.66
0.18
2.81
0.12
0.18
0.12
0.01
0.04
0.03
0.48
0.99
0.62
0.81
NR
0.56
NR
1.19
0.31
0.30
0.26
NR
0.05
NR
0.36
1.32
1.37
1.09
0.05
0.57
0.19
3.17
0.26
0.49
0.32
0.03
0.05
0.06
0.85
1.37
0.84
0.74
0.04
0.72
0.25
4.52
0.19
0.18
0.12
0.01
0.07
0.07
0.64
1.20
0.71
0.84
0.06
0.74
0.12
1.50
0.20
0.19
0.22
0.03
0.08
0.03
0.30
to
ON
oo
NR = Not reportable due to the low number of measured detections.
-------
• The seasonal averages did not vary much, with the exceptions of formaldehyde and
carbon tetrachloride.
• Formaldehyde was significantly higher in the summer than in other seasons.
• Carbon tetrachloride was higher in the summer and autumn than in other seasons.
The following observations for MSTN are shown in Table 26-3:
• Formaldehyde had the highest daily average concentration by mass (2.81 ± 0.48
//g/m3), followed by acetaldehyde (1.26 ± 0.12 jug/m3).
• Most of the pollutants of interest had seasonal averages that varied little, with the
exception of carbon tetrachloride and formaldehyde.
• Formaldehyde was significantly higher in the spring and summer (3.17 ± 0.85 jug/m3
and 4.52 ± 0.64 //g/m3, respectively) than in winter or autumn (1.19 ± 0.36 jug/m3 and
1.50 ± 0.30 //g/m3, respectively).
• Carbon tetrachloride was higher in summer and autumn than in other seasons.
26.3 Non-Chronic Risk Evaluation
Non-chronic risk is evaluated using ATSDR short-term (acute) and intermediate MRL
and California EPA acute REL factors. Acute risk is defined as exposures from 1 to 14 days
while intermediate risk is defined as exposures from 15 to 364 days. It is useful to compare the
preprocessed daily measurements to the short-term MRL and REL factors, as well as compare
seasonal averages to the intermediate MRL. Of the pollutants with at least one failed screen at
either site, only acrolein exceeded the acute risk values, and its non-chronic risk is summarized in
Table 26-4.
The following observations about acrolein are shown in Table 26-4:
• All of the measured detections of acrolein at the Tennessee monitoring sites exceeded
the ATSDR acute value of 0.11 //g/m3and all but one exceeded the California REL
value of 0.19 jug/m3.
• The average acrolein concentration for MSTN was higher than for LDTN (1.00 ± 0.18
jug/m3 vs. 0.64 ±0.10 //g/m3, respectively).
• Seasonal acrolein averages were used to evaluate intermediate risk. Every seasonal
average for both Tennessee sites exceeded the intermediate risk factor.
26-9
-------
Table 26-4. Non-Chronic Risk Summary for the Tennessee Monitoring Sites
Site
LDTN
MSTN
Method
TO- 15
TO- 15
Pollutant
Acrolein
Acrolein
Daily
Average
(ug/m3)
0.64 ±0.10
1.00 ±0.18
ATSDR
Short-term
MRL
(ug/m3)
0.11
0.11
# of ATSDR
MRL
Exceedances
48
44
CAL
EPA
REL
Acute
(ug/m3)
0.19
0.19
# of CAL
EPA REL
Exceedances
48
43
ATSDR
Intermediate
-term MRL
(Ug/m3)
0.09
0.09
Winter
Average
(Ug/m3)
0.64
±0.24
0.62
±0.30
Spring
Average
(Ug/m3)
0.46
±0.17
1.37
±0.49
Summer
Average
(Ug/m3)
0.72
±0.15
0.84
±0.18
Autumn
Average
(Ug/m3)
0.46
±0.16
0.71
±0.19
to
-------
• For the MSTN site, the summer acrolein average of 1.37 ± 0.49 //g/m3 was more than
14 times the ATSDR intermediate-term MRL of 0.09 jug/m3.
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of daily
concentration and daily average wind direction. Figures 26-4 and 26-5 are pollution roses for
acrolein for the Tennessee monitoring sites.
Observations gleaned from the acrolein pollution roses include:
• Figure 26-4 shows that all acrolein concentrations exceeded the acute risk factors at
LDTN, indicated by a dashed (CALEPA REL) and solid line (ATSDR MRL). Figure
26-5 shows that all acrolein concentrations at MSTN exceeded the ATSDR MRL,
while all but one exceeded the CALEPA REL.
• The pollution roses for both sites showed few acrolein measured detections occurred
with southerly, southeasterly, or easterly winds.
• LDTN is located on a mile-wide strip of land bounded on either side by the Tennessee
River. A major roadway through town runs just to the northwest of the monitoring
site (Figure 26-1). MSTN is located to the southwest of LDTN and south of the town
of Loudon. Several point sources lie between LDTN and MSTN, which are located
about a mile apart.
26.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
26.4.1 Pearson Correlation Analysis
Table 26-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the Tennessee monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
26-11
-------
Figure 26-4. Acrolein Pollution Rose for LDTN
to
2.5
2.0
1.5
1.0
O
7=
2 0.5
Concent
o
o
4-1
c
| 0.5
0
Q.
1.0
1.5
2.0
2.5
3.0
NW , N
— CA EPA REL (0.19 |jg/m3)
— ATSDR MRL (0.1 1 |jg/m3)
-
-
-
*
W ..•»*£
^ • • 4*'^
•• tc;
* ^
-
-
-
sw s
NE
*
.%
y * E
'
Daily Ava Cone =0.64 ±0.10 ua/m3 SE I
1
3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 2.5 3
Pollutant Concentration
-------
Figure 26-5. Acrolein Pollution Rose for MSTN
to
3.5
3.0
2.5
2.0
1.5
§ 1.0
•£ 0.5
Ol
o
O 00
o
ra 0.5
"5 „ ~
ol 1.0
1.5
2.0
2.5
3.0
3.5
A n
NW , N
— CA EPA REL (0. 1 9 |jg/m3)
— ATSDR MRL (0.11 M9/m3)
-
-
-
-
•
*
^ 4
\A/ A" '
A. • ^ //*"
: '•%>^
* *•
^ *
*
-
-
-
OlAf O
SW S
NE
* * *
*< *
-------
Table 26-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Tennessee Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar Wind
Speed
Loudon, Tennessee - LDTN
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
56
48
55
48
55
51
56
0.39
0.12
-0.04
-0.21
0.42
0.02
0.84
0.32
0.18
-0.02
-0.25
0.42
0.08
0.82
0.14
0.22
0.03
-0.28
0.42
0.17
0.65
0.23
0.20
0.00
-0.27
0.43
0.13
0.74
-0.42
0.10
0.11
-0.04
0.02
0.21
-0.36
0.33
-0.13
0.22
0.30
0.12
-0.13
0.12
-0.26
-0.07
-0.11
-0.30
-0.23
0.08
-0.21
Loudon Middle School, Loudon, Tennessee - MSTN
Acetaldehyde
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
/>-Dichlorobenzene
Formaldehyde
51
44
49
40
49
47
51
0.34
0.19
-0.08
-0.26
0.22
0.52
0.79
0.27
0.17
-0.14
-0.32
0.24
0.56
0.80
0.02
0.07
-0.22
-0.30
0.29
0.48
0.62
0.13
0.11
-0.19
-0.32
0.27
0.54
0.72
-0.55
-0.19
-0.23
-0.03
0.20
-0.05
-0.35
0.35
-0.10
0.30
0.37
-0.11
-0.20
-0.16
-0.25
-0.05
-0.13
-0.25
-0.17
0.03
-0.03
to
-------
The following observations are gathered for LDTN from Table 26-5:
• Strong positive correlations were calculated between formaldehyde and maximum,
average, dew point, and wet bulb temperatures. This indicates that increasing
temperatures and moisture content lead to increasing formaldehyde concentrations.
This supports the high summer formaldehyde average discussed in Section 26.2.
• All of the correlations with scalar wind speed for LDTN were negative, with the
exception of />-dichlorobenzene, indicating that decreasing wind speeds lead to
increasing concentrations of most of the pollutants of interest.
The following observations are gathered for MSTN from Table 26-5:
• Strong positive correlations were calculated between formaldehyde and maximum,
average, dew point, and wet bulb temperatures. This indicates that increasing
temperatures and moisture content lead to increasing formaldehyde concentrations.
These formaldehyde correlations also support the higher summer formaldehyde
averages discussed in Section 26.2.
• />-Dichlorobenzene also exhibited strong positive correlations with maximum,
average, dew point, and wet bulb temperatures.
• Acetaldehyde exhibited a strong negative correlation with relative humidity,
indicating that increasing humidity leads to decreasing acetaldehyde concentrations.
• All of the correlations with scalar wind speed for MSTN were negative, with the
exception of />-dichlorobenzene, indicating that decreasing wind speeds lead to
increasing concentrations of most of the pollutants of interest.
26.4.2 Composite Back Trajectory Analysis
Figures 26-6 and 26-7 are composite back trajectory maps for the Tennessee monitoring
sites for the days on which sampling occurred. Each line represents the 24-hour trajectory along
which a parcel of air traveled toward the monitoring site on a sampling day. Each concentric
circle around the site represents 100 miles.
The following observations can be made from Figure 26-6 and 26-7:
• Back trajectories originated from a variety of directions at LDTN. The 24-hour
airshed domain was somewhat large at LDTN, with trajectories originating as far
away as Iowa or Texas, or greater than 600 miles away. However, most of the
trajectories originated within 300 miles of the site, and nearly all originate within 400
miles of the LDTN monitoring site.
26-15
-------
Figure 26-6. Composite Back Trajectory Map for LDTN
to
ON
Oi
0 50 100 200
Miles
-------
Figure 26-7. Composite Back Trajectory Map for MSTN
to
ON
-------
• Back trajectories also originated from a variety of directions at MSTN. The 24-hour
airshed domain was similar to LDTN's, with trajectories originating over 600 miles
away.
26.4.3 Wind Rose Analysis
Hourly wind data from the Knoxville McGhee-Tyson Airport weather station were
uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces a
graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
about a 16-point compass, and uses different shading to represent wind speeds. Figures 26-8 and
26-9 are the wind roses for the Tennessee monitoring sites on days that sampling occurred.
Observations from Figures 26-8 and 26-9 include:
• Hourly winds were predominantly out of the west, west-south west, and southwest on
days that samples were collected near MSTN and LDTN.
• Winds from these directions also tended to be stronger in nature than winds from
other directions.
• Calm winds (<2 knots) were recorded for approximately 20 percent of the hourly
observations.
26.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as this site did not sample for SNMOC.
26.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Dickson County and Loudon County
were obtained from the Tennessee Department of Safety and the U.S. Census Bureau, and are
summarized in Table 26-6. Table 26-6 also includes a vehicle registration to county population
ratio (vehicles per person). In addition, the population within 10 miles of each site is presented.
An estimation of 10-mile vehicle registration was computed using the 10-mile population
surrounding the monitor and the vehicle registration ratio. Finally, Table 26-6 contains the
26-18
-------
Figure 26-8. Wind Rose for LDTN Sampling Days
to
-------
Figure 26-9. Wind Rose for MSTN Sampling Days
to
to
o
SOUTH.-'
15%
WIND SPEED
(Knots)
17 • 21
^| 11 - 17
I I 4- 7
^| 2- 4
Calms: 21.01%
-------
Table 26-6. Motor Vehicle Information for the Tennessee Monitoring Sites
Site
LDTN
MSTN
2006 Estimated
County Population
44,566
44,566
Number of
Vehicles
Registered
50,519
50,519
Vehicles per Person
(Registration:
Population)
1.13
1.13
Population
Within 10 Miles
48,670
48,670
Estimated 10 mile
Vehicle Ownership
55,171
55,171
Traffic Data
(Daily Average)
12,945
7,287
to
-------
average daily traffic information, which represents the average number of vehicles passing the
monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 26-6 include:
• The county populations, vehicle registration, and vehicle-to-population ratio are all
the same for LDTN and MSTN because they are in the same county. In addition,
these sites are within the same zip code, so their 10-mile population and vehicle
registration are also the same.
• The sites vary when it comes to traffic count, with LDTN having nearly twice the
daily traffic passing the site.
• Compared to other UATMP sites, LDTN and MSTN are in the lower third of sites for
population and vehicle registration. Both are in the top 10 sites for vehicle to
population ratio.
26.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that the
concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-2 depict the average concentration ratios of the roadside study and compared them to the
concentration ratios at each of the Tennessee monitoring sites in an effort to characterize the
impact of on-road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• The ratios of the Tennessee sites generally resemble each other.
• For both sites, the toluene-ethylbenzene ratio was significantly higher than the
roadside study.
• The benzene-ethylbenzene ratio was higher than the xylenes-ethylbenzene ratio for
both sites, which is the reverse of the roadside study.
26.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
26-22
-------
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. The
LDTN monitoring site has participated in the UATMP since 2003. Figure 26-10 presents the
trends analysis for formaldehyde, benzene, and 1,3-butadiene for LDTN. MSTN has not
participated in the UATMP for three consecutive years, therefore a trends analysis was not
conducted.
Results from the trend analysis for LDTN include:
• Concentrations of formaldehyde decreased significantly between 2003 and 2005 at
the LDTN monitoring site; the concentration remained steady in 2006.
• 1,3-Butadiene was not detected during the 2003 program year; concentrations peaked
in 2004 and have decreased since then.
• Concentrations of benzene have been fairly constant at LDTN.
26.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Tennessee sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 26-7.
Additionally, the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA were
retrieved and are also presented in Table 26-7. The NATA data are presented for the census
tracts where the monitoring sites are located.
The census tract information for the Tennessee sites is as follows:
• The census tract for LDTN is 47105060200, which had a population of 9,529, which
represents approximately 24.4 percent of the Loudon County population in 2000.
• The census tract for MSTN is 47105060500, which had a population of 7,898, which
also represents approximately 20.2 percent of the county population in 2000.
26-23
-------
to
I
to
35
30
25
">"
Q.
| 20
TO
0)
o
o
O 15
0)
O)
TO
0)
10
Figure 26-10. Comparison of Yearly Averages for the LDTN Monitoring Site
2003
2004
2005
2006
Year
D1,3-Butadiene
I Benzene
D Formaldehyde
-------
Table 26-7. Chronic Risk Summary for the Monitoring Sites in Tennessee
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(Hg/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Loudon, Tennessee (LDTN) - Census Tract ID 47105060200
Acet aldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
Chloromethylbenzene
p-Dichlorobenzene
Formaldehyde
Hexachloro- 1 ,3 -butadiene
1, 1,2,2-Tetrachloroethane
Tetrachloroethylene
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000049
0.000011
5.5E-09
0.000022
0.000058
0.0000059
0.009
0.00002
0.002
0.03
0.002
0.04
NR
0.8
0.0098
0.09
NR
0.27
1.22
0.06
0.01
0.89
0.03
0.21
0.01
0.02
0.78
0.01
0.01
0.02
2.69
NR
0.06
6.95
0.77
3.19
0.01
0.17
O.01
0.03
0.72
0.15
0.14
2.99
0.01
0.03
0.01
0.01
NR
O.01
0.08
0.01
NR
O.01
2.21 ±0.32
0.58 ±0.10
0.07 ±0.01
1.02 ±0.12
0.06 ±0.01
0.65 ±0.06
0.01 ±0.01
0.11 ±0.02
2.58 ±0.47
0.09 ±0.02
0.05 ±0.01
0.07 ±0.01
4.86
NR
4.43
7.99
1.84
9.82
0.71
1.26
0.01
1.90
2.61
0.41
0.25
28.90
0.03
0.03
0.03
0.02
NR
O.01
0.26
0.01
NR
O.01
Loudon, Tennessee (MSTN) - Census Tract ID 47105060500
Acet aldehyde
Acrolein
Acrylonitrile
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
Formaldehyde
Tetrachloroethylene
0.0000022
NR
0.000068
0.0000078
0.00003
0.000015
0.000011
5.5E-09
0.0000059
0.009
0.00002
0.002
0.03
0.002
0.04
0.8
0.0098
0.27
1.05
0.05
O.01
0.72
0.02
0.21
0.01
0.73
0.02
2.31
NR
0.04
5.60
0.47
3.16
0.12
O.01
0.10
0.12
2.39
O.01
0.02
0.01
0.01
O.01
0.07
0.01
1.26 ±0.12
0.91 ±0.18
0.09 ±0.03
0.87 ±0.12
0.05 ±0.01
0.66 ± 0.04
0.17 ±0.03
2.81 ±0.48
0.09 ±0.03
2.76
NR
5.88
6.79
1.41
9.94
1.88
0.02
0.52
0.14
45.72
0.04
0.03
0.02
0.02
O.01
0.29
0.01
to
I
to
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
-------
The following observations can be made from Table 26-7:
• Formaldehyde and acetaldehyde had the highest annual averages by mass
concentration for the Tennessee sites. Although the formaldehyde averages were
fairly similar, acetaldehyde average was significantly lower for MSTN.
• Carbon tetrachloride and benzene had the highest annual average-based cancer risks
for LDTN and MSTN, while acrolein had the highest noncancer risk for both sites.
• While the carbon tetrachloride and benzene risks were similar for both sites, the
acrolein HQ was significantly higher for MSTN.
• NATA-modeled concentrations and risks of the pollutants of interest for the
Tennessee sites were fairly similar.
• For both sites, acetaldehyde, benzene, and formaldehyde had the highest
concentrations; benzene, carbon tetrachloride, and acetaldehyde had the highest
cancer risks; acrolein had the only noncancer HQ greater than 1.0.
26.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 26-8 and 26-9 present a
risk-based assessment of county-lev el emissions based on cancer and noncancer toxicity,
respectively. Table 26-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 26-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. The Tennessee sites sampled for VOC and carbonyl compounds only.
In addition, the highest cancer and noncancer risks based on annual averages are limited to those
pollutants failing at least one screen.
26-26
-------
Table 26-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Tennessee
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(London County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(Loudon County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Pollutant
Cancer Risk
(in-a-million)
Loudon, Tennessee - LDTN
Benzene
Acetaldehyde
Formaldehyde
1,3 -Butadiene
Dichloromethane
Naphthalene
Tetrachloroethylene
Poly cyclic Organic Matter as 15 -PAH
£>-Dichlorobenzene
Trichloroethylene
79.28
56.93
26.50
7.50
3.84
2.10
2.06
1.19
0.89
0.49
Benzene
1,3 -Butadiene
Acetaldehyde
Arsenic
Naphthalene
Poly cyclic Organic Matter as 15-PAH
Hexavalent Chromium
Polycyclic Organic Matter as 7-PAH
Poly cyclic Organic Matter as non-15 PAH
Nickel
6.18E-04
2.25E-04
1.25E-04
1.14E-04
7.14E-05
6.55E-05
5.75E-05
4.60E-05
3.55E-05
2.43E-05
Carbon Tetrachloride
Benzene
Acetaldehyde
Acrylonitrile
1, 1,2,2-Tetrachloroethane
Hexachloro- 1 ,3 -butadiene
1,3 -Butadiene
£>-Dichlorobenzene
Chloromethylbenzene
Tetrachloroethylene
9.82
7.99
4.86
4.43
2.61
1.90
1.84
1.26
0.71
0.41
Loudon, Tennessee - MSTN
Benzene
Acetaldehyde
Formaldehyde
1,3 -Butadiene
Dichloromethane
Naphthalene
Tetrachloroethylene
Poly cyclic Organic Matter as 15-PAH
£>-Dichlorobenzene
Trichloroethylene
79.28
56.93
26.50
7.50
3.84
2.10
2.06
1.19
0.89
0.49
Benzene
1,3 -Butadiene
Acetaldehyde
Arsenic
Naphthalene
Polycyclic Organic Matter as 15-PAH
Hexavalent Chromium
Polycyclic Organic Matter as 7-PAH
Polycyclic Organic Matter as non-15 PAH
Nickel
6.18E-04
2.25E-04
1.25E-04
1.14E-04
7.14E-05
6.55E-05
5.75E-05
4.60E-05
3.55E-05
2.43E-05
Carbon Tetrachloride
Benzene
Acrylonitrile
Acetaldehyde
£>-Dichlorobenzene
1,3 -Butadiene
Tetrachloroethylene
Formaldehyde
9.94
6.79
5.88
2.76
1.88
1.41
0.52
0.02
to
to
-------
Table 26-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Tennessee
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(London County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(Loudon County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Pollutant
Noncancer
Risk (HQ)
Loudon, Tennessee - LDTN
Carbon Bisulfide
Toluene
Hydrochloric Acid
Xylenes
Styrene
Benzene
Acetaldehyde
Hexane
Ethylbenzene
Methanol
1,130.08
200.00
146.47
133.59
85.00
79.28
56.93
33.19
32.76
27.13
Acrolein
Manganese
Hydrochloric Acid
Acetaldehyde
1,3 -Butadiene
Formaldehyde
Benzene
Nickel
Carbon Bisulfide
Xylenes
75,675.31
10,827.61
7,323.53
6,325.04
3,750.57
2,704.13
2,642.72
2,337.56
1,614.40
1,335.93
Acrolein
Formaldehyde
Acetaldehyde
Benzene
Acrylonitrile
1,3 -Butadiene
Carbon Tetrachloride
Hexachloro- 1 , 3 -butadiene
Tetrachloroethylene
£>-Bichlorobenzene
28.90
0.26
0.25
0.03
0.03
0.03
0.02
<0.01
0.01
0.01
Loudon, Tennessee - MSTN
Carbon Bisulfide
Toluene
Hydrochloric Acid
Xylenes
Styrene
Benzene
Acetaldehyde
Hexane
Ethylbenzene
Methanol
1,130.08
200.00
146.47
133.59
85.00
79.28
56.93
33.19
32.76
27.13
Acrolein
Manganese
Hydrochloric Acid
Acetaldehyde
1,3 -Butadiene
Formaldehyde
Benzene
Nickel
Carbon Bisulfide
Xylenes
75,675.31
10,827.61
7,323.53
6,325.04
3,750.57
2,704.13
2,642.72
2,337.56
1,614.40
1,335.93
Acrolein
Formaldehyde
Acetaldehyde
Acrylonitrile
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Tetrachloroethylene
£>-Bichlorobenzene
45.72
0.29
0.14
0.04
0.03
0.02
0.02
O.01
O.01
-------
The following observations can be made from Table 26-8:
• Benzene was the highest emitted pollutant with a cancer risk factor, had the highest
cancer toxicity-weighted emissions, and had the second highest cancer risk based on
the 2006 annual averages for LDTN and MSTN.
• Carbon tetrachloride had the highest cancer risk based on the 2006 annual averages
for both sites, yet this pollutant was neither one of the highest emitted nor one of the
most toxic in Loudon County, based on the 2002 NEI emission inventory.
• In addition to benzene, acetaldehyde and 1,3-butadiene appeared on all three "top 10"
lists.
The following observations can be made from Table 26-9:
• Carbon disulfide was the highest emitted pollutant with a noncancer risk factor in
Loudon County. This pollutant had the ninth highest noncancer toxicity-weighted
emissions for Loudon County.
• Like most UATMP counties, acrolein had the highest noncancer toxicity-weighted
emissions and had the highest noncancer risks based on the 2006 annual averages for
both sites. However, acrolein did not appear in the list of highest emitted pollutants.
Tennessee Pollutant Summary
• The pollutants of interest common to each of the Tennessee sites were acetaldehyde,
acrolein, benzene, 1,3-butadiene, carbon tetrachloride, formaldehyde, and, p-
dichlorobenzene.
• Formaldehyde had the highest daily average for both MSTN and LDTN. Formaldehyde
was also highest during summer for both sites.
• Acrolein exceeded the short-term risk factors at both Tennessee sites.
• A comparison of formaldehyde, benzene and 1,3-butadiene concentrations for all years of
UA IMP participation showed that concentrations formaldehyde decreased at LDTN since
the onset of sampling in 2003 through 2005, then held steady in 2006.
26-29
-------
27.0 Sites in Texas
This section presents meteorological, concentration, and spatial trends for the five
UATMP sites in or near the Austin, Texas area (MUTX, PITX, RRTX, TRTX, WETX, and
YDSP). One UATMP site, YDSP, is located in El Paso. Figures 27-1 through 27-6 are
topographical maps showing the monitoring sites in their urban and rural locations. Figures 27-7
and 27-8 identify point source emission locations within 10 miles of each site as reported in the
2002 NEI for point sources. As Figure 27-7 shows, four monitoring sites are located within
Travis County and the city of Austin (MUTX, PITX, TRTX, and WETX), while one is located
further north in the neighboring town of Round Rock in Williamson County (RRTX). The
monitoring sites are oriented in a line running roughly north-south, with RRTX the furthest north
and TRTX the furthest south. There are a variety of point sources in the Austin area including,
but not limited to, rubber and miscellaneous plastic products production, processes using utility
boilers, mineral product processing, and chemical and allied product production. YDSP is
located within a mile of the US-Mexico border, as shown in Figure 27-8. Most of the nearby
sources (US only) are located to the north and northwest of the monitoring site, and are primarily
involved in fuel combustion industries, liquids distribution, and petroleum and natural gas
production and refining. Across the border from YSDP in Mexico is Ciudad Juarez, a large
industrial city.
Sites sampling in the Austin, Texas area were funded to sample for one year, beginning
in the summer of 2005 and continuing through the summer of 2006, though the start and end
dates vary slightly from site-to-site. The YSDP site sampled from March 2005 to March 2006.
In order to facilitate analysis, the entire dataset for the one year of sampling for these sites is
included here, as described in Section 3.0.
The city of Austin experiences a modified subtropical climate, that is, mild winters with
only a handful of below freezing temperatures each year, and hot, muggy summers, due in part to
the flow from the Gulf of Mexico. Northerly winds are prevalent in the winter and southeasterly
winds are predominant in the summer. Precipitation is fairly evenly distributed throughout the
year, through most frequently in the form of thunderstorms in the spring and summer. In
contrast to Austin, El Paso's climate is more characteristic of the desert southwest. Winters are
27-1
-------
Figure 27-1. Austin, Texas (MUTX) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
27-2
-------
Figure 27-2. Austin, Texas (PITX) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
27-3
-------
Figure 27-3. Round Rock, Texas (RRTX) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
27-4
-------
Figure 27-4. Austin, Texas (TRTX) Monitoring Site
*jfe3 mf xm
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
27-5
-------
Figure 27-5. Austin, Texas (WETX) Monitoring Site
xS^Q/H
/Q
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
27-6
-------
Figure 27-6. El Paso, Texas (YDSP) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000
27-7
-------
Figure 27-7. Facilities Located Within 10 Miles of MUTX, PITX, RRTX, TRTX, and
WETX
Williamson
County
Travis
County
Hays
County
Ba strop
County
Legend
T^ MUTX UATMP Site ^T TRTX UATMP Site
FSj PITX UATMP site (Sj WETX UATMP site
^ RRTX UATMP site
Source Category Group (No. of Facilities)
c Chemicals & Allied Products Facility (3)
z Electrical & Electronic Equipment Facility (1}
D Fabricated Metal Products Facility (1)
F Fuel Combustion Industrial Facility (1)
J Industrial Machinery & Equipment Facility (2)
•= Instruments & Related Products Facility (1}
T Integrated Iron & Steel Manufacturing Facility (1)
L Liquids Distribution Industrial Facility (2)
Note: Due to facility density and collocation, the total facilities
diapiayed may nol represent al facilities wi&hin the area of interest.
10 mile radius
County boundary
& Lumber & Wood Products Facility (1)
B Mineral Products Processing Industrial Facility (2)
P Miscellaneous Processes Industrial Facility (7)
> Pharmaceutical Production Processes Industrial Facility (1)
V Polymers & Resins Production Industrial Facility (1)
Y Rubber & Miscellaneous Plastic Products Facility (3)
s Surface Coating Processes Industrial Facility (1)
a Utility Boilers (2)
v Waste Treatment & Disposal Industrial Facility (1)
27-8
-------
Figure 27-8. Facilities Located Within 10 Miles of YDSP
Note; Due to faditty density and collocation, the to*al facilities
displayed may noS represent alfl facilities within the area of interest
Legend
•&• YDSP UATMP site
10 mile radius
County boundary
Source Category Group (No. of Facilitation)
z Electrical & Electronic Equipment Facility (T)
D Fabricated Metal Products Facility (2)
F Fuel Combustion Industrial Facility (5)
H Furniture & Fixtures Facility (1)
L Liquids Distribution Industrial Facility (3)
* Non-ferrous Metals Processing Industrial Facility (2)
p Petroleum/Nat. Gas Prod & Refining Industrial Facility (3)
Y Rubber & Miscellaneous Plastic Products Facility (2)
27-9
-------
very mild, summers are hot, often with large diurnal temperature fluctuations, and precipitation
is infrequent. Summertime thunderstorms tend to produce the heaviest rainfalls. Dust and
sandstorms occur occasionally (Ruffner and Bair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2005 and 2006. These data were used to determine how meteorological conditions on sampling
days vary from normal conditions throughout the year. They were also used to calculate
correlations of meteorological data with ambient air concentration measurements. The weather
station closest to the MUTX and PITX monitoring sites is Camp Mabry Army National Guard
(WBAN 13958); the weather station closest to the TRTX and WETX monitoring sites is Austin-
Bergstrom International Airport (WBAN 13904); the closest weather station to RRTX is
Georgetown Municipal Airport (WBAN 53942); and El Paso International Airport (WBAN
23044) is closest to YDSP.
Table 27-1 presents average meteorological conditions of temperature (average
maximum and average), moisture (average dew point temperature, average wet-bulb
temperature, and average relative humidity), pressure (average sea level pressure), and wind
information (average scalar wind speed) from July 2005 to June 2006 for the Austin sites, and
April 2005 to March 2006 for YDSP as well as on days samples were collected. Also included
in Table 27-1 is the 95 percent confidence interval for each parameter. As shown in Table 27-1,
average meteorological conditions on sampling days were representative of average weather
conditions throughout the year.
27.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Texas
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the guidance document as having risk screening values. If the daily concentration
value was greater than the risk screening value, then the measured concentration "failed the
screen." Pollutants of interest are those in which the individual pollutant's total failed screens
27-10
-------
Table 27-1. Average Meteorological Conditions near the Monitoring Sites in Texas
Site
MUTX
PITX
RRTX
TRTX
WETX
YDSP
WBAN
13958
13958
53942
13904
13904
23044
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
82.08
±1.39
83.43
±3.76
82.08
±1.39
83.14
±3.91
80.65
± 1.43
82.83
±4.04
83.22
±1.37
83.94
±4.02
83.22
± 1.37
85.00
±3.83
78.72
±1.45
76.00
±3.47
Average
Temperature
(°F)
70.65
±1.33
72.28
±3.74
70.65
±1.33
72.13
±3.87
68.66
±1.42
70.86
±4.23
70.17
±1.38
71.53
±4.13
70.17
±1.38
72.48
±3.93
66.82
±1.49
64.07
±3.49
Average
Dew Point
Temperature
(°F)
53.55
±1.63
54.47
±4.91
53.55
±1.63
54.53
±5.04
49.92
±1.62
52.04
±4.97
54.99
±1.65
55.90
±5.32
54.99
±1.65
57.12
±5.06
33.72
±1.82
31.33
±4.52
Average
Wet Bulb
Temperature
(°F)
61.04
±1.27
62.20
±3.67
61.04
±1.27
62.17
±3.77
60.05
± 1.26
61.16
±3.92
61.49
±1.33
62.61
±4.12
61.49
± 1.33
63.58
±3.93
50.51
±1.23
48.53
±2.96
Average
Relative
Humidity
(%)
59.14
±1.45
57.87
±4.41
59.14
±1.45
58.29
±4.55
55.06
± 1.21
55.46
±3.53
63.53
±1.30
62.92
±4.50
63.53
±1.30
63.44
±4.18
34.11
±1.64
34.06
±4.18
Average
Sea Level
Pressure
(mb)
1015.95
±0.60
1015.84
±1.34
1015.95
±0.60
1016.05
±1.38
NA1
NA1
1015.73
±0.60
1015.57
± 1.53
1015.73
±0.60
1015.66
±1.36
1012.35
±0.59
1013.01
± 1.47
Average
Scalar Wind
Speed
(kt)
4.75
±0.20
4.90
±0.71
4.75
±0.20
5.03
±0.73
6.38
±0.30
5.49
±0.97
6.60
±0.30
6.44
±1.03
6.60
±0.30
6.20
±0.98
7.48
±0.35
8.02
±1.08
to
lrrhis station did not record seal level pressure
-------
contribute to the top 95 percent of the site's total screens. Table 27-2 presents the pollutants that
failed at least one screen at the Texas monitoring sites. The Austin sites sampled for carbonyls,
VOC, and metals, while the El Paso site sampled for VOC only. In addition, WETX also
sampled for hexavalent chromium. The Austin sites also sampled for total NMOC, but TNMOC
is not considered in the determination of the pollutants of interest. The number of pollutants
failing the screen varies by site, as indicated in Table 27-2, and a brief summary of each site's
risk screening is provided below:
• Fifteen pollutants with a total of 250 measured concentrations failed screens at
MUTX;
• Thirteen pollutants with a total of 240 measured concentrations failed screens at
PITX;
• Fourteen pollutants with a total of 265 measured concentrations failed screens at
RRTX;
• Nineteen pollutants with a total of 270 measured concentrations failed screens at
TRTX;
• Twenty pollutants with a total of 277 measured concentrations failed screens at
WETX; and
• Nine pollutants with a total of 273 measured concentrations failed screens at YDSP.
Additional observations from Table 27-2 include:
• The pollutants of interest also varied by site, yet the following five pollutants
contributed to the top 95 percent of the total failed screens at each Texas monitoring
site: acrolein, benzene, 1,3-butadiene, carbon tetrachloride, and/?-dichlorobenzene.
• Of the five pollutants that were the same among all six sites, three pollutants of
interest, acrolein, benzene, and carbon tetrachloride, had 100 percent of their
measured detections fail screens.
27-12
-------
Table 27-2. Comparison of Measured Concentration and EPA Screening Values for
the Texas Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Murchison Middle School, Austin, Texas - MUTX
Carbon Tetrachloride
Benzene
Formaldehyde
Acetaldehyde
Acrolein
1,3 -Butadiene
Arsenic (PM10)
/>-Dichlorobenzene
Tetrachloroethylene
Manganese (PM10)
Hexachloro- 1 ,3 -butadiene
1 ,2-Dichloroethane
Nickel (PM10)
Chloromethylbenzene
Acrylonitrile
Total
31
31
30
30
26
23
23
20
17
10
5
1
1
1
1
250
31
31
30
30
26
24
30
25
21
30
5
1
30
1
1
316
100.00
100.00
100.00
100.00
100.00
95.83
76.67
80.00
80.95
33.33
100.00
100.00
3.33
100.00
100.00
79.11
12.40
12.40
12.00
12.00
10.40
9.20
9.20
8.00
6.80
4.00
2.00
0.40
0.40
0.40
0.40
12.40
24.80
36.80
48.80
59.20
68.40
77.60
85.60
92.40
96.40
98.40
98.80
99.20
99.60
100.00
Pickle Research Center, Austin, Texas - PITX
Acetaldehyde
Benzene
Carbon Tetrachloride
Formaldehyde
Arsenic (PM10)
Acrolein
1,3 -Butadiene
£>-Dichlorobenzene
Manganese (PM10)
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
Nickel (PM10)
Trichloroethylene
Total
31
31
31
31
26
24
22
19
16
4
o
5
i
i
240
31
31
31
31
32
24
26
28
32
15
3
32
4
320
100.00
100.00
100.00
100.00
81.25
100.00
84.62
67.86
50.00
26.67
100.00
3.13
25.00
75.00
12.92
12.92
12.92
12.92
10.83
10.00
9.17
7.92
6.67
1.67
1.25
0.42
0.42
12.92
25.83
38.75
51.67
62.50
72.50
81.67
89.58
96.25
97.92
99.17
99.58
100.00
Round Rock, Texas - RRTX
Formaldehyde
Acetaldehyde
Benzene
Carbon Tetrachloride
Acrolein
Arsenic (PM10)
£>-Dichlorobenzene
1,3 -Butadiene
32
32
30
30
26
26
25
22
32
32
30
30
26
33
29
24
100.00
100.00
100.00
100.00
100.00
78.79
86.21
91.67
12.08
12.08
11.32
11.32
9.81
9.81
9.43
8.30
12.08
24.15
35.47
46.79
56.60
66.42
75.85
84.15
27-13
-------
Table 27-2. Comparison of Measured Concentration and EPA Screening Values for
the Texas Monitoring Sites (Continued)
Pollutant
Manganese (PM10)
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
Acrylonitrile
Nickel (PM10)
Chloromethylbenzene
Total
#of
Failures
18
16
5
1
1
1
265
#of
Measured
Detections
33
23
5
1
33
1
332
%of
Screens
Failed
54.55
69.57
100.00
100.00
3.03
100.00
79.82
% of Total
Failures
6.79
6.04
1.89
0.38
0.38
0.38
Cumulative
%
Contribution
90.94
96.98
98.87
99.25
99.62
100.00
Travis High School, Austin, Texas - TRTX
Carbon Tetrachloride
Benzene
Acetaldehyde
Formaldehyde
1,3 -Butadiene
Arsenic (PM10)
/>-Dichlorobenzene
Acrolein
Manganese (PM10)
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
Cadmium (PM10)
1 ,2-Dichloroethane
Chloromethylbenzene
1 , 1 ,2,2-Tetrachloroethane
1, 1,2-Trichloroethane
Nickel (PM10)
1 ,2-Dibromoethane
Vinyl Chloride
Total
31
31
30
30
28
26
25
22
16
11
6
6
2
270
31
31
30
30
28
30
29
22
30
17
6
30
2
1
1
1
30
1
10
360
100.00
100.00
100.00
100.00
100.00
86.67
86.21
100.00
53.33
64.71
100.00
20.00
100.00
100.00
100.00
100.00
3.33
100.00
10.00
75.00
11.48
11.48
11.11
11.11
10.37
9.63
9.26
8.15
5.93
4.07
2.22
2.22
0.74
0.37
0.37
0.37
0.37
0.37
0.37
11.48
22.96
34.07
45.19
55.56
65.19
74.44
82.59
88.52
92.59
94.81
97.04
97.78
98.15
98.52
98.89
99.26
99.63
100.00
Webberville Road, Austin, Texas - WETX
Arsenic (PM10)
Benzene
Carbon Tetrachloride
1,3 -Butadiene
/>-Dichlorobenzene
Acetaldehyde
Formaldehyde
Manganese (PM10)
Acrolein
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
Xylenes
1 ,2-Dichloroethane
31
28
28
28
27
24
24
23
22
11
8
7
5
34
28
28
28
27
29
29
34
22
21
8
28
5
91.18
100.00
100.00
100.00
100.00
82.76
82.76
67.65
100.00
52.38
100.00
25.00
100.00
11.19
10.11
10.11
10.11
9.75
8.66
8.66
8.30
7.94
3.97
2.89
2.53
1.81
11.19
21.30
31.41
41.52
51.26
59.93
68.59
76.90
84.84
88.81
91.70
94.22
96.03
27-14
-------
Table 27-2. Comparison of Measured Concentration and EPA Screening Values for
the Texas Monitoring Sites (Continued)
Pollutant
Acrylonitrile
1 , 1 ,2,2-Tetrachloroethane
Nickel (PM10)
Cadmium (PM10)
Hexavalent Chromium
Chloromethylbenzene
1 ,2-Dibromoethane
Total
#of
Failures
4
2
277
#of
Measured
Detections
4
2
34
34
21
1
1
418
%of
Screens
Failed
100.00
100.00
2.94
2.94
4.76
100.00
100.00
66.27
% of Total
Failures
1.44
0.72
0.36
0.36
0.36
0.36
0.36
Cumulative
%
Contribution
97.47
98.19
98.56
98.92
99.28
99.64
100.00
El Paso, Texas - YDSP
Benzene
Carbon Tetrachloride
1,3 -Butadiene
£>-Dichlorobenzene
Acrolein
Tetrachloroethylene
Hexachloro- 1 ,3 -butadiene
Xylenes
Trichloroethylene
Total
57
57
51
43
21
15
14
12
o
6
273
57
57
51
46
21
28
14
57
32
363
100.00
100.00
100.00
93.48
100.00
53.57
100.00
21.05
9.38
75.21
20.88
20.88
18.68
15.75
7.69
5.49
5.13
4.40
1.10
20.88
41.76
60.44
76.19
83.88
89.38
94.51
98.90
100.00
27.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. The seasons presented for the Texas sites
will range from Spring 2005 through Spring 2006 in order to accommodate their summer-to-
summer sampling schedule. A summer 2006 seasonal average will not be possible due to the
low number of samples compared to the detection criteria. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
27-15
-------
Annual averages are calculated for monitoring sites where sampling began no later than February
and ended no earlier than November, but this duration has been adjusted for the Texas sites. The
daily and seasonal average concentrations are presented in Table 27-3. Annual averages are
presented and discussed in further detail in later sections.
The following observations for the Austin sites are shown in Table 27-3:
• Among the daily averages for the Austin sites, acrolein measured the highest
concentration by mass, ranging from 5.50 ± 2.93 |ig/m3 for PITX to 9.08 ± 3.70
|ig/m3 for RRTX.
• Formaldehyde had the second highest daily average for each Austin site, ranging
from 3.28 ± 0.77 |ig/m3 for MUTX to 3.72 ± 0.52 |ig/m3 for RRTX.
• With the exception of WETX, acetaldehyde measured the third highest daily average
for each Austin site.
• As the Austin sites did not begin monitoring until mid-June, late-June, or early July
2005, no seasonal averages could be calculated for spring and summer 2005 (except
for metals). In addition, the l-in-12 sampling schedule limited the seasonal average
availability. With the exception of MUTX, acrolein autumn averages could not be
calculated.
• The autumn seasonal averages that were available did not differ significantly from the
daily averages for the Austin monitoring sites.
The following observations for the El Paso site are shown in Table 27-3:
• The pollutants with the highest daily averages were total xylenes (7.37 ±1.37 |ig/m3),
acrolein (4.48 ± 4.09 |ig/m3), and benzene (2.33 ± 0.34 |ig/m3).
• The YDSP site began sampling in March. Although many of the pollutants of interest
had higher concentrations in autumn than spring or summer, most of these differences
were not statistically significant.
• The one exception was the autumn benzene concentration.
• Acrolein had no seasonal averages due to a low detection rate.
27-16
-------
Table 27-3. Daily and Seasonal Averages for the Pollutants of Interest for the Texas Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Ug/m3)
Conf.
Int.
Spring 2005
Avg
(Ug/m3)
Conf.
Int.
Summer 2005
Avg
(Ug/m3)
Conf.
Int.
Autumn 2005
Avg
(Ug/m3)
Conf.
Int.
Winter 2006
Avg
(Ug/m3)
Conf.
Int.
Spring 2006
Avg
(Ug/m3)
Conf.
Int.
Murchison Middle School, Austin, Texas - MUTX
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Manganese (PM10)
Tetrachloroethylene
30
26
30
31
24
31
25
30
30
21
30
30
30
31
31
31
31
30
30
31
1.43
4.31
0.001
0.94
0.09
0.63
0.26
2.82
0.005
0.37
0.18
1.36
0.001
0.13
0.02
0.06
0.10
0.44
0.001
0.12
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NR
NR
0.001
NR
NR
NR
NR
NR
0.002
NR
NR
NR
0.001
NR
NR
NR
NR
NR
0.001
NR
1.83
4.89
0.001
1.07
0.11
0.74
0.21
2.82
0.007
0.42
0.32
2.63
0.001
0.13
0.02
0.07
0.07
0.74
0.004
0.22
NR
NR
0.001
NR
NR
NR
NR
NR
0.005
NR
NR
NR
0.001
NR
NR
NR
NR
NR
0.001
NR
1.38
NR
NR
0.67
NR
0.58
NR
2.52
NR
NR
0.22
NR
NR
0.19
NR
0.17
NR
0.35
NR
NR
Pickle Research Center, Austin, Texas - PITX
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Manganese (PM10)
31
24
32
31
26
31
28
31
32
31
30
32
31
31
31
31
31
32
1.43
3.13
O.001
0.80
0.08
0.68
0.25
2.88
0.006
0.19
1.36
O.001
0.11
0.02
0.06
0.09
0.44
0.002
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
1.83
NR
0.001
1.04
0.13
0.73
0.20
3.12
0.009
0.36
NR
O.001
0.23
0.03
0.08
0.09
0.62
0.005
NR
NR
0.001
NR
NR
NR
NR
NR
0.007
NR
NR
O.001
NR
NR
NR
NR
NR
0.002
1.25
1.63
O.001
0.58
NR
0.59
0.09
2.32
0.004
0.25
0.62
O.001
0.14
NR
0.15
0.02
0.30
0.001
Round Rock, Texas - RRTX
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
/>-Dichlorobenzene
32
26
33
30
24
30
29
32
29
33
30
30
30
30
1.47
5.14
O.001
0.98
0.09
0.66
0.27
0.17
2.08
O.001
0.18
0.03
0.06
0.10
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NR
NR
O.001
NR
NR
NR
NR
NR
NR
O.001
NR
NR
NR
NR
1.77
NR
0.001
1.10
0.11
0.73
0.24
0.19
NR
O.001
0.16
0.04
0.11
0.08
NR
NR
0.001
NR
NR
NR
NR
NR
NR
O.001
NR
NR
NR
NR
1.23
2.66
NR
0.63
NR
0.58
0.14
0.23
1.39
NR
0.13
NR
0.13
0.03
-------
Table 27-3. Daily and Seasonal Averages for the Pollutants of Interest for the Texas Monitoring Sites (Continued)
Pollutant
Formaldehyde
Manganese (PM10)
Tetrachloroethylene
#of
Measured
Detections
32
33
23
#of
Samples
32
33
30
Daily
Avg
(Ug/m3)
3.30
0.006
0.32
Conf.
Int.
0.39
0.001
0.11
Spring 2005
Avg
(Ug/m3)
NA
NA
NA
Conf.
Int.
NA
NA
NA
Summer 2005
Avg
(Ug/m3)
NR
0.003
NR
Conf.
Int.
NR
0.001
NR
Autumn 2005
Avg
(Ug/m3)
3.41
0.008
0.30
Conf.
Int.
0.44
0.003
0.12
Winter 2006
Avg
(Ug/m3)
NR
0.008
NR
Conf.
Int.
NR
0.003
NR
Spring 2006
Avg
(Ug/m3)
2.58
NR
NR
Conf.
Int.
0.28
NR
NR
Travis High School, Austin, Texas - TRTX
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Cadmium (PM10)
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese (PM10)
Tetrachloroethylene
30
22
30
31
28
30
31
29
30
6
30
17
30
31
30
31
31
30
31
31
30
31
30
31
1.49
3.62
0.001
1.11
0.16
O.001
0.68
0.27
3.01
0.20
0.005
0.31
0.21
1.38
0.001
0.17
0.03
O.001
0.07
0.08
0.45
0.12
0.001
0.12
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
1.81
NR
0.001
1.31
0.21
0.001
0.69
0.30
3.35
NR
0.007
NR
0.35
NR
0.001
0.27
0.06
O.001
0.12
0.10
0.59
NR
0.003
NR
1.27
NR
0.001
NR
NR
O.001
NR
NR
1.89
NR
0.006
NR
0.09
NR
0.001
NR
NR
O.001
NR
NR
0.30
NR
O.001
NR
1.30
2.21
NR
0.75
NR
NR
0.57
0.11
2.54
NR
NR
NR
0.41
1.02
NR
0.23
NR
NR
0.11
0.03
0.46
NR
NR
NR
Webberville Road, Austin, Texas - WETX
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese (PM10)
Tetrachloroethylene
29
22
34
28
28
28
27
5
29
8
34
21
29
26
34
28
28
28
28
27
29
28
34
28
1.69
4.87
0.001
1.88
0.33
0.67
0.41
0.08
2.72
0.20
0.007
0.24
0.35
1.24
0.001
0.32
0.09
0.04
0.08
0.02
0.54
0.05
0.001
0.07
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NR
NR
O.001
NR
NR
NR
NR
NR
NR
NR
0.004
NR
NR
NR
O.001
NR
NR
NR
NR
NR
NR
NR
0.002
NR
2.30
NR
0.003
2.04
0.39
0.70
0.39
NR
3.50
NR
0.009
0.21
0.43
NR
0.003
0.58
0.15
0.08
0.14
NR
0.39
NR
0.003
0.09
NR
NR
0.001
2.07
0.43
0.60
0.40
NR
NR
NR
0.007
0.28
NR
NR
O.001
0.88
0.27
0.12
0.17
NR
NR
NR
0.002
0.17
1.54
NR
0.001
NR
NR
NR
NR
NR
2.44
NR
0.005
NR
0.55
NR
O.001
NR
NR
NR
NR
NR
0.87
NR
0.001
NR
-------
Table 27-3. Daily and Seasonal Averages for the Pollutants of Interest for the Texas Monitoring Sites (Continued)
Pollutant
Xylenes
#of
Measured
Detections
28
#of
Samples
28
Daily
Avg
(Ug/m3)
9.43
Conf.
Int.
4.22
Spring 2005
Avg
(Ug/m3)
NA
Conf.
Int.
NA
Summer 2005
Avg
(Ug/m3)
NR
Conf.
Int.
NR
Autumn 2005
Avg
(Ug/m3)
5.73
Conf.
Int.
2.17
Winter 2006
Avg
(Ug/m3)
5.35
Conf.
Int.
3.27
Spring 2006
Avg
(Ug/m3)
NR
Conf.
Int.
NR
El Paso, Texas - YDSP
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Hexachloro-1 ,3 -butadiene
Tetrachloroethylene
Xylenes
21
57
51
57
46
14
28
57
43
57
57
57
57
57
57
57
2.25
2.39
0.36
0.59
0.51
0.19
0.53
7.32
1.94
0.30
0.06
0.04
0.14
0.04
0.62
1.10
NR
1.79
NR
0.53
NR
NR
NR
5.24
NR
0.33
NR
0.06
NR
NR
NR
1.33
NR
1.65
0.20
0.59
0.29
NR
NR
5.85
NR
0.50
0.08
0.06
0.13
NR
NR
2.60
NR
2.68
0.32
0.72
0.72
1.02
0.13
7.81
NR
0.44
0.08
0.08
0.37
0.40
0.04
1.59
0.62
3.12
0.52
0.55
0.53
NR
0.18
9.80
0.20
0.62
0.13
0.06
0.13
NR
0.06
2.12
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA= Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
to
-------
27.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for Texas monitoring sites was evaluated
using ATSDR short-term (acute) and intermediate MRL and California EPA acute REL factors.
Acute risk is defined as exposures from 1 to 14 days while intermediate risk is defined as
exposures from 15 to 364 days. It is useful to compare the preprocessed daily measurements to
the short-term MRL and REL factors, as well as compare seasonal averages to the intermediate
MRL. Of the pollutants with at least one failed screen, only acrolein exceeded either the acute or
the intermediate risk values at the Texas sites, and each site's non-chronic risk is summarized in
Table 27-4.
The following observations about acrolein are shown in Table 27-4:
• All of the acrolein measured detections at the Texas sites were greater than the
ATSDR acute value of 0.11 |ig/m3 and the California REL value of 0.19 |ig/m3.
• The average daily concentration ranged from 2.25 ± 1.94 |ig/m3 (for YDSP) to 5.14 ±
2.08 |ig/m3 (for RRTX), which were an order of magnitude higher than either acute
risk factor.
• Few seasonal averages for acrolein could be calculated for the Texas sites,
predominately due to a low overall detection rate and a l-in-12 sampling schedule.
However, seasonal averages of acrolein, where available, exceeded the intermediate
risk MRL.
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of
concentration and wind direction. For all six Texas monitoring sites, only acrolein
concentrations exceeded the acute risk factors. Figures 27-9 through 27-14 are pollution roses
for acrolein for the Texas sites. As discussed above, all acrolein concentrations exceeded the
acute risk factors, which are indicated by a dashed line (CalEPA REL) and solid line (ATSDR
MRL). Because the scale in Figures 27-9 through 27-14 is so large, the risk factors cannot be
shown accurately, and therefore do not appear on the pollution roses. However, the values of the
risk factors are still provided in the Figures.
27-20
-------
Table 27-4. Non-Chronic Risk Summary for the Texas Monitoring Sites
Site
MUTX
PITX
RRTX
TRTX
WETX
YDSP
Method
TO-15
TO-15
TO-15
TO-15
TO-15
TO-15
Pollutant
Acrolein
Acrolein
Acrolein
Acrolein
Acrolein
Acrolein
Daily
Average
(ug/m3)
4.31 ±
1.36
3.13 ±
1.36
5.14 ±
2.08
3.62 ±
1.38
4.87±
1.24
2.25 ±
1.94
ATSDR
Short-
term
MRL
(ug/m3)
0.11
0.11
0.11
0.11
0.11
0.11
# of ATSDR
MRL
Exceedances
26
24
26
22
22
21
CAL EPA
REL
Acute
(ug/m3)
0.19
0.19
0.19
0.19
0.19
0.19
# of CAL
EPA REL
Exceedances
26
24
26
22
22
21
ATSDR
Intermediate
MRL
(ug/m3)
0.09
0.09
0.09
0.09
0.09
0.09
Spring
2005
Average
(Ug/m3)
NA
NA
NA
NA
NA
NR
Summer
2005
Average
(Ug/m3)
NR
NR
NR
NR
NR
NR
Autumn
2005
Average
(Ug/m3)
4.89±
2.63
NR
NR
NR
NR
NR
Winter
2006
Average
(Ug/m3)
NR
NR
NR
NR
NR
0.62 ±
0.20
Spring
2006
Average
(Ug/m3)
NR
1.63±
0.62
2.66 ±
1.39
2.21 ±
1.02
NR
NA
to
^1
to
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
-------
14.0
12.0
10.0
8.0
6.0
Figure 27-9. Acrolein Pollution Rose for MUTX
NW
NE
to
to
to
4.0
tant Concentra
2.0 |
1 w
0 0
2.0 1
^ »
t«
*
-
* • * E
O
Q.
4.0
6.0
8.0
10-0
14.0
sw
Due to scale contraints, the risk factors,
CA EPA REL (0.19 ug/m3) and ATSDR
MRL (0.11 ug/m3), are not pictured here.
14.0
Dailv Ava Cone =4.31 ± 1 .36 ua/m3
SE
12.0 10.0 8.0 6.0 4.0 2.0 0.0 2.0
Pollutant Concentration
4.0
6.0
8.0
10.0
12.0
14.0
-------
Figure 27-10. Acrolein Pollution Rose for PITX
to
^i
to
14.0
12.0
10.0
8.0
6.0
4.0
0.0
i: 2.0
c
-------
Figure 27-11. Acrolein Pollution Rose for RRTX
18.0
16.0
14.0
12.0
10.0
8.0
6.0
§
i 4-°
^ 1 2-°
I 0
t0 n 00
rv O u-u
•^ o
c 2.0
S
= 4.0
O
Q.
6.0
8.0
10.0
12.0
14.0
16.0
18.0
20.0
NW
W
O1AI
OVV
Due to scale contraints, the risk factrs,
CA EPA REL (0.19 ug/rn3) and
ATSDR MRL (0.11 ug/rn3), are not
pictured here.
N
.
-
-
-
-
-
-
**
*<
A
-
-
-
-
,
-
-
NE
> A E
A ^
^
** •
*
__
4^
»
^
Daily Ava Cone =5. 14 ±2.08 ua/m3 SE
__»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_»_^
20.0 18.0 16.0 14.0 12.0 10.0 8.0 6.0 4.0 2.0 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0
Pollutant Concentration
-------
Figure 27-12. Acrolein Pollution Rose for TRTX
to
^1
to
12.0
10.0
8.0
6.0
40
O
co
£ 2.0
itant Concer
N) O
b b
* 4,
6.0
8.0
10.0
12.0
NW
W
SW
14.0
Due to scale contraints, the risk factrs,
CA EPA REL (0.19 ug/m3) and
ATSDR MRL(0.11 ug/m3), are not
pictured here.
14.0 12.0 10.0 8.0 6.0 4.0
N
.
-
4
-
**
-
-
-
-
-
S
J
DailvAva Cone =3.62 ±1. 38 ua/m3 NE
^
S • E
* *
* *
** *
'
SE
2.0 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14
Pollutant Concentration
-------
Figure 27-13. Acrolein Pollution Rose for WETX
.0
'S
^ I
^ 1
hj n
i^^ O
ON O
'c
•2
"o
Q.
NW
12.0
10.0
8.0
6.0
4.0
2.0
W
0 0
2.0
4.0
6.0
8.0
10.0
12.0
14 n
sw -
Due to scale contraints, the risk factrs,
q
CA EPA REL (0.19 ug/m3) and
ATSDR MRL (0.1 1 ug/m3), are not
pictured here.
)ailv Ava Cone =4.87 ± 1 .24 uq/m3
N
_
4
*
-
4) '
.
-
-
-
S
NE
*
4>
>
E
•
^
*
* *
* *
4.
*
*
SE
14.0 12.0 10.0 8.0 6.0 4.0 2.0 0.0 2.0
Pollutant Concentration
4.0
6.0 8.0 10.0 12.0 14.0
-------
Figure 27-14. Acrolein Pollution Rose for YDSP
to
^1
to
o
O
o
18.0
16.0
14.0
12.0
10.0
8.0
6.0
4.0
2.0
n n
u.u
2.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
on n
zu.u
2C
NW
W
QIAf
OVV
.0 18.0
Due to scale contraints, the risk factrs,
CA EPA REL (0.19 ug/m3) and
ATSDR MRL (0.1 1 ug/m3), are not
pictured here.
16.0 14.0 12.0 10.0 8.0 6.0 4
N
-
-
-
-
-
^ *.
^H
-
-
-
-
-
-
.0 2.0 0
NE
£ E
&^* »
*
DailvAvaConc=2.25±1.94ua/m3 SE
0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20
Pollutant Concentration
-------
Observations gleaned from the acrolein pollutions roses include:
• Figure 27-9 is the acrolein pollution rose for the MUTX monitoring site. The
pollution rose shows that concentrations exceeding the acute risk factors occurred
with winds originating from a variety of directions, which is a characteristic of mobile
sources, although there is an apparent lack of measured detections associated with a
southwesterly wind. The MUTX monitoring site is located in a primarily residential
area on the Murchison Middle School grounds. The eastern edge of the school
grounds is bordered by a major thoroughfare, the Mo-Pac expressway, which is
paralleled by a railway. The highest concentration of acrolein occurred on August 26,
2005 with a southeasterly wind.
• Figure 27-10 is the acrolein pollution rose for the PITX monitoring site, and its
pattern is similar to MUTX's pollution rose. The pollution rose shows that
concentrations exceeding the acute risk factors occurred with winds originating from
a variety of directions, which is a characteristic of mobile sources, although there is
an apparent lack of measured detections associated with northeasterly and
southwesterly winds. The PITX monitoring site is located at the University of Texas
Pickle Research Center, which is near the intersection of two major roadways: the
Mo-Pac Expressway and Highway 183. The highest concentration of acrolein also
occurred on August 26, 2005 with a southeasterly wind.
• Figure 27-11 is the acrolein pollution rose for the RRTX monitoring site. The
pollution rose shows that concentrations exceeding the acute risk factors occurred
with winds originating from a variety of directions, which is a characteristic of mobile
sources. The RRTX monitoring site is located on the northern edge of a residential
area. Just to the west of the monitoring site, running north-south, is 1-35. The
Georgetown railroad parallels 1-35 on the west side. The highest concentration of
acrolein occurred on August 2, 2005 with an east-southeasterly wind.
• Figure 27-12 is the acrolein pollution rose for the TRTX monitoring site. The
pollution rose shows that concentrations exceeding the acute risk factors occurred
with winds originating from a variety of directions, which is a characteristic of mobile
sources. The TRTX monitoring site is located at Travis High School, which is just
off 1-35 on Oltorf Street, in a highly residential area of Austin. The highest
concentration of acrolein occurred on August 14, 2005 with a south-southeasterly
wind.
• Figure 27-13 is the acrolein pollution rose for the WETX monitoring site. The
pollution rose shows that concentrations exceeding the acute risk factors occurred
with winds originating from a variety of directions, which is a characteristic of mobile
sources, although primarily from the southeast and south. The WETX monitoring site
is located in a residential area off East 7th Street, which intersects 1-35 about a mile
and half west of the site. The Northwestern Railroad loops around the area where
WETX is located. Zaragosa Park and Recreation Center is very close to the
monitoring site. The highest concentration of acrolein occurred on June 10, 2006
with a south-southeasterly wind.
27-28
-------
• Figure 27-14 is the acrolein pollution rose for the YDSP monitoring site. The
pollution rose shows that concentrations exceeding the acute risk factors occurred
with winds originating from a variety of directions, which is a characteristic of mobile
sources. Most of the acrolein measured detections are within a tight cluster around
the center of the pollution rose, with most concentrations less than 2.0 |ig/m3.
However, the highest concentrations of acrolein occurred on July 5 and 11, 2005 with
an east and east-southeasterly wind. The YDSP monitoring site is located in a
residential area on the southeast side of El Paso, TX. The 375 Loop, or Americas
Avenue, runs less than a mile to the south of the site. The 375 Loop intersects I-10 a
couple miles east of YDSP. The US-Mexican border is less than 1.5 miles from the
site.
27.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
27.4.1 Pearson Correlation Analysis
Table 27-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the Texas monitoring sites.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for the Austin sites from Table 27-5:
• At most of the Austin sites, strong positive correlations were calculated between
acrolein, />-dichlorobenzene, and formaldehyde and maximum, average, dew point,
and wet bulb temperatures, indicating that concentrations of these pollutants increase
as temperature and moisture content increase.
• Most of the correlations between the pollutants of interest and scalar wind speed were
negative, indicating that as wind speeds decrease, concentrations of the pollutants of
interest tend to increase.
The following observations are gathered for the El Paso site from Table 27-5:
• With few exceptions, all of the correlations between the pollutants of interest and the
temperature and moisture parameters were negative, which indicates that as
temperature and moisture content decrease, concentrations of the pollutants of interest
tend to increase.
27-29
-------
Table 27-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Texas Monitoring Sites
to
Pollutant
#of
Measured
Detections
Maximum
Temperature
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea
Level
Pressure
Scalar
Wind
Speed
Murchison Middle School, Austin, Texas - MUTX
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
/>-Dichlorobenzene
Formaldehyde
Manganese (PM10)
Tetrachloroethylene
30
26
30
31
24
31
25
30
30
21
0.13
0.59
0.22
0.24
-0.22
0.26
0.59
0.63
-0.30
-0.15
0.13
0.59
0.25
0.25
-0.27
0.18
0.58
0.66
-0.37
-0.14
0.12
0.39
0.25
0.43
-0.01
0.00
0.57
0.51
-0.31
-0.16
0.10
0.49
0.25
0.36
-0.14
0.06
0.60
0.57
-0.35
-0.16
0.06
-0.13
0.14
0.49
0.44
-0.27
0.15
0.07
-0.10
-0.07
0.10
0.04
-0.24
-0.25
0.18
-0.06
-0.15
-0.14
0.32
0.25
-0.71
-0.56
-0.19
-0.51
-0.45
-0.13
-0.34
-0.52
0.14
-0.44
Pickle Research Center, Austin, Texas - PITX
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Manganese (PM10)
31
24
32
31
26
31
28
31
32
-0.06
0.54
-0.08
0.11
-0.24
0.29
0.58
0.66
-0.30
-0.07
0.50
-0.06
0.10
-0.30
0.27
0.58
0.67
-0.39
-0.11
0.38
0.09
0.12
-0.33
0.14
0.50
0.51
-0.40
-0.12
0.44
0.02
0.10
-0.33
0.20
0.54
0.58
-0.41
-0.12
0.02
0.34
0.11
-0.26
-0.15
0.06
0.01
-0.23
0.17
-0.21
-0.12
-0.02
0.55
-0.29
-0.25
-0.21
0.26
-0.38
-0.49
-0.31
-0.44
-0.49
0.18
-0.30
-0.36
-0.07
Round Rock, Texas - RRTX
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
32
26
33
30
24
30
29
0.17
0.29
-0.18
0.20
-0.05
0.27
0.44
0.09
0.32
-0.18
0.15
-0.16
0.27
0.44
-0.05
0.37
-0.07
0.08
-0.22
0.26
0.46
-0.05
0.38
-0.03
0.02
-0.37
0.36
0.39
-0.11
0.26
0.23
-0.04
-0.30
0.18
0.21
NA1
NA1
NA1
NA1
NA1
NA1
NA1
-0.45
-0.22
-0.29
-0.39
-0.12
-0.37
-0.25
-------
Table 27-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Texas Monitoring Sites (Continued)
to
Pollutant
Formaldehyde
Manganese (PM10)
Tetrachloroethylene
#of
Measured
Detections
32
33
23
Maximum
Temperature
0.44
-0.38
-0.07
Travis Hi
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Cadmium (PM10)
Carbon Tetrachloride
£>-Dichlorobenzene
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese (PM10)
Tetrachloroethylene
30
22
30
31
28
30
31
29
30
6
30
17
-0.03
0.58
0.25
0.09
-0.07
-0.05
0.36
0.50
0.53
-0.52
-0.37
-0.22
Temperature
0.44
-0.54
-0.13
Dew Point
Temperature
0.37
-0.59
-0.25
Wet Bulb
Temperature
0.35
-0.50
-0.07
Relative
Humidity
0.07
-0.40
-0.07
Sea
Level
Pressure
NA1
NA1
NA1
Scalar
Wind
Speed
-0.53
0.03
0.25
gh School, Austin, Texas - TRTX
-0.03
0.51
0.28
0.04
-0.21
0.02
0.26
0.40
0.53
-0.56
-0.49
-0.31
0.04
0.49
0.29
0.12
-0.16
0.15
0.06
0.38
0.46
-0.45
-0.42
-0.24
0.01
0.52
0.29
0.09
-0.20
0.10
0.14
0.39
0.50
-0.51
-0.47
-0.29
0.13
0.17
0.20
0.24
0.02
0.31
-0.38
0.14
0.15
0.17
-0.14
-0.01
0.17
-0.12
-0.10
0.09
0.16
-0.04
-0.09
-0.16
-0.08
0.03
0.37
0.27
-0.38
-0.05
0.00
-0.39
-0.43
0.15
0.25
-0.30
-0.27
0.54
-0.07
-0.05
Webberville Road, Austin, Texas - WETX
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 , 3 -butadiene
Manganese (PM10)
Tetrachloroethylene
29
22
34
28
28
28
27
5
29
8
34
21
-0.29
0.70
-0.22
-0.05
-0.22
0.33
0.20
0.87
-0.04
-0.02
-0.32
-0.10
-0.39
0.70
-0.35
-0.19
-0.39
0.30
0.02
0.85
-0.13
0.10
-0.46
-0.19
-0.30
0.55
-0.31
-0.07
-0.30
0.37
0.06
0.72
-0.04
0.15
-0.53
-0.01
-0.35
0.62
-0.34
-0.14
-0.36
0.34
0.03
0.75
-0.08
0.15
-0.53
-0.11
0.00
0.06
-0.06
0.20
-0.01
0.36
0.15
0.34
0.16
0.20
-0.41
0.32
0.33
-0.19
0.29
-0.08
0.07
-0.22
-0.28
-0.81
0.21
-0.24
0.35
-0.30
-0.56
-0.42
-0.33
-0.60
-0.46
-0.02
-0.40
-0.57
-0.56
0.05
0.00
-0.36
-------
Table 27-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Texas Monitoring Sites (Continued)
The station nearest RRTX did not record sea level pressure.
Pollutant
Xylenes
#of
Measured
Detections
28
Maximum
Temperature
0.33
Temperature
0.31
Dew Point
Temperature
0.19
Wet Bulb
Temperature
0.23
Relative
Humidity
-0.10
Sea
Level
Pressure
-0.28
Scalar
Wind
Speed
0.00
El Paso, Texas - YDSP
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Hexachloro- 1 , 3 -butadiene
Tetrachloroethylene
Xylenes
21
57
51
57
46
14
28
57
0.64
-0.28
-0.44
0.00
0.07
-0.15
-0.06
-0.20
0.58
-0.40
-0.53
0.03
0.00
-0.11
0.01
-0.30
0.36
-0.46
-0.60
0.22
-0.07
-0.15
-0.07
-0.40
0.44
-0.47
-0.61
0.14
-0.06
-0.16
-0.03
-0.39
-0.05
-0.31
-0.40
0.33
-0.17
-0.15
-0.13
-0.33
-0.43
0.28
0.36
0.12
-0.02
0.01
-0.45
0.23
-0.04
-0.47
-0.32
-0.29
-0.35
0.12
0.82
-0.43
to
to
-------
• Like the Austin sites, most of the correlations with scalar wind speed were negative.
However, tetrachloroethylene exhibited a very strong positive correlation with this
parameter.
27.4.2 Composite Back Trajectory Analysis
Figures 27-15 through 27-20 are composite back trajectory maps for the Texas
monitoring sites for the days on which sampling occurred. Each line represents the 24-hour
trajectory along which a parcel of air traveled toward the monitoring site on a sampling day.
Each concentric circle around the site represents 100 miles.
The following observations can be made from Figures 27-15 through 27-19:
• Back trajectories predominantly originated from the southeast for the Austin sites.
• The 24-hour airshed domains were rather large at these sites, with trajectories
originating as far away as Nebraska (> 800 miles). However, the bulk of the
trajectories originated within 500 miles of the sites.
• Trajectories originating to the northwest of the sites were the longest, which indicates
that stronger winds originated from the northwest.
The following observations can be made from Figure 27-20:
• Back trajectories originated from a variety of directions at YDSP, although most
frequently from the southeast, southwest, and west.
• The 24-hour airshed domain was somewhat smaller at YDSP, with trajectories
originating as far away as near Baja California (> 400 miles).
• However, most of the trajectories originated within 300 miles of the site.
• The majority of the 24-hour back trajectories originated from Mexico.
27.4.3 Wind Rose Analysis
As mentioned in Section 27.0, weather data from the four closest weather stations to
monitoring sites were obtained to correlate concentrations and meteorological conditions.
Hourly wind data from these stations were uploaded into a wind rose software program,
WRPLOT (Lakes, 2006). WRPLOT produces a graphical wind rose from the wind data. A
wind rose shows the frequency of wind directions about a 16-point compass, and uses different
27-33
-------
Figure 27-15. Composite Back Trajectory Map for MUTX
to
-------
Figure 27-16. Composite Back Trajectory Map for PITX
to
-------
Figure 27-17. Composite Back Trajectory Map for RRTX
to
-------
Figure 27-18. Composite Back Trajectory Map for TRTX
to
-------
Figure 27-19. Composite Back Trajectory Map for WETX
to
oo
J / I I
7 / /
1 \ V
-------
Figure 27-20. Composite Back Trajectory Map for YDSP
to
VO
-------
shading to represent wind speeds. Figures 27-21 through 27-26 are the wind roses for the Texas
monitoring sites on days that sampling occurred.
Observations from Figures 27-21 through 27-25 include:
• Hourly winds were predominantly out of the south, southeast, and south-southeast on
days that samples were collected near the Austin sites.
• Calm winds (<2 knots) were recorded for 23 to 33 percent of the hourly
measurements.
• Wind speeds ranged from 7 to 11 knots near these sites.
Observations from Figures 27-26 include:
• The wind rose for YDSP was much different than the wind roses for the Austin sites.
• Hourly winds were predominantly out of the east (11 percent of observations), north
(10 percent), and west (9 percent) near YDSP on days that samples were collected.
• Calm winds (<2 knots) were recorded for less than 11 percent of the hourly
measurements.
• For wind speeds greater than 2 knots, over 30 percent of observations ranged from 7
to 11 knots.
• Figure 27-26 shows that wind speeds greater than 22 knots tended to occur most
frequently with southwesterly and westerly winds.
27.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as these sites did not sample for SNMOC.
27.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Travis, Williamson, and El Paso
Counties were obtained from the Texas Department of Transportation and the U.S. Census
Bureau, and are summarized in Table 27-6. Table 27-6 also includes a vehicle registration to
county population ratio (vehicles per person). In addition, the population within 10 miles of each
27-40
-------
Figure 27-21. Wind Rose for MUTX Sampling Days
/VEST
to
NORTH"---.
15%
12%
SOUTH,-'"
I I
EAST
WIND SPEED
(Knots)
| | >= 22
I I 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 32.69%
-------
Figure 27-22. Wind Rose for PITX Sampling Days
/VEST
to
= 22
I I 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 31.40%
-------
Figure 27-23. Wind Rose for RRTX Sampling Days
•WEST !
to
NORTH"---.
20%
16%
12%
lOUTH,-'-
!EAST
WIND SPEED
(Knots)
17 - 21
I I 11 - 17
I I 7- 11
^| 2- 4
Calms: 24.47%
-------
Figure 27-24. Wind Rose for TRTX Sampling Days
/VEST
to
15%
SOUTH--'
WIND SPEED
(Knots)
| | >= 22
I I 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 23.22%
-------
Figure 27-25. Wind Rose for WETX Sampling Days
WEST
to
NORTH"
20%
16%
8%.
12%
I I
SOUTH,-''
I I
EAST
WIND SPEED
(Knots)
| | >=22
^| 17 - 21
I I 11 - 17
I I A- 7
^| 2- 4
Calms: 24.3
-------
Figure 27-26. Wind Rose for YDSP Sampling Days
to
15%
SOUTH.---
WIND SPEED
(Knots)
| | >= 22
I I 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
^| 2- 4
Calms: 10.45%
-------
Table 27-6. Motor Vehicle Information for the Texas Monitoring Sites
Site
MUTX
PITX
RRTX
TRTX
WETX
YDSP
2006 Estimated
County
Population
921,006
921,006
353,830
921,006
921,006
736,310
Number of
Vehicles Registered
731,956
731,956
285,183
731,956
731,956
533,438
Vehicles per Person
(Registration:
Population)
0.79
0.79
0.81
0.79
0.79
0.72
Population
Within 10 Miles
696,128
672,699
387,701
560,699
677,505
443,463
Estimated 10
Mile Vehicle
Ownership
553,238
534,618
312,483
445,607
538,437
321,278
Traffic Data
(Daily
Average)
4,374
33,936
20,900
27,114
5,733
12,400
to
-------
site is presented. An estimation of 10-mile vehicle registration was computed using the 10-mile
population surrounding the monitor and the vehicle registration ratio. Finally, Table 27-6
contains the average daily traffic information, which represents the average number of vehicles
passing the monitoring sites on the nearest roadway to each site on a daily basis.
Observations gleaned from Table 27-6 include:
• The RRTX monitoring site has a significantly lower county and 10-mile population
than the other Austin sites, as well as a significantly lower county and 10-mile
estimated vehicle ownership.
• The vehicle-population ratios are very similar for Travis and Williamson Counties.
• The YDSP site has a higher population and vehicle ownership than RRTX, but is
lower than the remaining Austin sites.
• Due to its low vehicle per person ratio, although the YDSP's 10-mile population is
higher than RRTX, the 10-mile vehicle ownership near YDSP is just slightly higher
than at RRTX.
• Of the five Austin sites, PITX experiences the most daily traffic, while MUTX
experiences the least.
• Compared to other UATMP sites, the four Austin-proper sites are on the lower end of
the more populous locations.
• The vehicle per person ratios for MUTX, PITX, RRTX, TRTX, and WETX are in the
middle of the range of UATMP sites, while the YDSP ratio is on the low-side.
27.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compared them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impacts of on-
road, or motor vehicle, emissions.
27-48
-------
The BTEX table and figure show the following:
• Of the six Texas sites, the YDSP monitoring site's ratios most resembled those of the
roadside study, suggesting that mobile source emissions are a major influence at this
site, although its benzene-ethylbenzene and xylenes-ethylbenzene ratios were closer
together than the roadside study's (3.02 ± 0.27 and 3.59 ± 0.08 for YDSP vs. 2.85 and
4.55 for the roadside study).
• The ratios for MUTX, PITX, TRTX, and WETX were very similar to each other.
The ratios were all lower than those of the roadside study and the benzene-
ethylbenzene and xylenes-ethylbenzene ratios were closer together than those of the
roadside study.
• The RRTX ratios resemble the other Austin sites except that its toluene-ethylbenzene
ratio was significantly higher than those of the other sites and those of the roadside
study (11.87 ± 1.77 for RRTX and 5.85 for the roadside study).
27 .6 Trends Analysis
A trends analysis could not be performed for the Texas sites as these sites have not
participated in the UATMP for three consecutive years.
27.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Texas sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 27-7.
Additionally, the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA were
retrieved and are also presented in Table 27-7. The NATA data are presented for the census tract
where the monitoring site is located.
The following observations can be made about MUTX, PITX, RRTX, and TRTX for the
annual averages-based risks from Table 27-7:
• Formaldehyde and acrolein had the two highest annual averages of all the pollutants
of interest for MUTX, PITX, RRTX, and TRTX. However, formaldehyde presents
very little cancer risk, as shown by its cancer URE, and acrolein has no cancer risk
factor.
27-49
-------
Table 27-7. Chronic Risk Summary for the Monitoring Sites in Texas
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2005/2006 UATMP
Annual
Average
(Hg/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Murchison Middle School, Austin, Texas (MUTX) - Census Tract ID 48453001718
Acetaldehyde
Acrolein
Acrylonitrile
Arsenic
Benzene
1,3-Butadiene
Carbon Tetrachloride
Chloromethylbenzene
p-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese
Nickel
Tetrachloroethylene
0.0000022
NR
0.000068
0.0043
0.0000078
0.00003
0.000015
0.000049
0.000011
0.000026
5.5E-09
0.000022
NR
0.00016
0.0000059
0.009
0.00002
0.002
0.00003
0.03
0.002
0.04
NR
0.8
2.4
0.0098
0.09
0.00005
0.000065
0.27
1.57
0.11
0.00
0.01
1.75
0.16
0.22
0.00
0.03
0.04
1.57
0.00
0.35
0.00
0.24
3.45
NR
0.01
0.04
13.63
4.94
3.24
0.01
0.38
0.95
0.01
0.03
NR
0.03
1.42
0.17
5.35
0.01
0.01
0.06
0.08
0.01
NR
0.01
O.01
0.16
O.01
0.01
0.01
O.01
1.43 ±0.18
3.74 ± 1.29
0.07 ±0.03
0.01 ±0.01
0.94 ±0.13
0.08 ±0.02
0.63 ± 0.06
0.06 ± 0.02
0.22 ± 0.09
0.05 ±0.01
2.82 ±0.44
0.56 ±0.24
0.01 ±0.01
0.01 ±0.01
0.27 ±0.10
3.15
NR
4.97
2.04
7.31
2.27
9.50
2.81
2.43
1.40
0.02
12.34
NR
0.18
1.60
0.16
186.97
0.04
0.02
0.03
0.04
0.02
NR
0.01
O.01
0.29
0.01
0.10
0.02
O.01
Pickle Research Center, Austin, Texas (PITX) - Census Tract ID 48453001849
Acetaldehyde
Acrolein
Arsenic
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese
Nickel
0.0000022
NR
0.0043
0.0000078
0.00003
0.000015
0.000011
5.5E-09
0.000022
NR
0.00016
0.009
0.00002
0.00003
0.03
0.002
0.04
0.8
0.0098
0.09
0.00005
0.000065
1.67
0.12
0.01
1.70
0.16
0.21
0.03
1.75
0.00
1.89
0.49
3.67
NR
0.06
13.24
4.7
3.17
0.35
0.01
0.03
NR
0.08
0.19
6.22
0.01
0.06
0.08
0.01
0.01
0.18
O.01
0.04
0.01
1.43 ±0.19
2.51 ±1.18
0.01 ±0.01
0.80 ±0.11
0.07 ± 0.02
0.68 ±0.06
0.23 ± 0.09
2.88 ±0.44
0.75 ±0.32
0.01 ±0.01
O.01±O.01
3.14
NR
1.95
6.22
2.15
10.20
2.57
0.02
16.50
NR
0.20
0.16
125.65
0.02
0.03
0.04
0.02
0.01
0.29
0.01
0.12
0.02
to
-------
Table 27-7. Chronic Risk Summary for the Monitoring Sites in Texas (Continued)
Pollutant
Tetrachloroethylene
Trichloroethylene
Cancer
URE
Oig/m3)
0.0000059
0.000002
Noncancer
RfC
Oig/m3)
0.27
0.6
1999 NATA
Modeled
Concentration
(Hg/m3)
0.24
0.09
Cancer Risk
(in-a-
million)
1.4
0.18
Noncancer
Risk (HQ)
O.01
0.01
2005/2006 UATMP
Annual
Average
(Hg/m3)
0.11 ±0.03
0.09 ±0.05
Cancer
Risk (in-a-
million)
0.65
0.18
Noncancer
Risk (HQ)
O.01
0.01
Round Rock, Texas (RRTX) - Census Tract ID 48491021502
Acetaldehyde
Acrolein
Acrylonitrile
Arsenic
Benzene
1,3-Butadiene
Carbon Tetrachloride
Chloromethylbenzene
p-Dichlorobenzene
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Manganese
Nickel
Tetrachloroethylene
0.0000022
NR
0.000068
0.0043
0.0000078
0.00003
0.000015
0.000049
0.000011
5.5E-09
0.000022
NR
0.00016
0.0000059
0.009
0.00002
0.002
0.00003
0.03
0.002
0.04
NR
0.8
0.0098
0.09
0.00005
0.000065
0.27
1.31
0.08
0.00
0.01
1.36
0.11
0.21
0.00
0.04
1.32
0.00
0.14
0.00
0.15
2.89
NR
0.01
0.03
10.61
3.34
3.21
O.01
0.46
0.01
0.03
NR
0.03
0.9
0.15
4.18
O.01
0.01
0.05
0.06
0.01
NR
0.01
0.13
0.01
0.01
O.01
0.01
1.47 ±0.17
4.61 ±1.95
0.06 ±0.01
0.01 ±0.01
0.98 ±0.18
0.08 ±0.03
0.66 ± 0.06
0.05 ±0.02
0.27 ± 0.09
3.03 ±0.39
0.58 ±0.25
0.01 ±0.01
O.01±O.01
0.26 ±0.09
3.24
NR
4.08
2.10
7.66
2.38
9.88
2.60
2.93
0.02
12.75
NR
0.20
1.52
0.16
230.36
0.03
0.02
0.03
0.04
0.02
NR
0.01
0.34
0.01
0.11
0.02
0.01
Travis High School, Austin, Texas (TRTX) - Census Tract ID 48453002308
Acetaldehyde
Acrolein
Arsenic
Benzene
1,3-Butadiene
Cadmium
Carbon Tetrachloride
Chloromethylbenzene
1 ,2-Dibromoethane
/7-Dichlorobenzene
0.0000022
NR
0.0043
0.0000078
0.00003
0.0018
0.000015
0.000049
0.00022
0.000011
0.009
0.00002
0.00003
0.03
0.002
0.00002
0.04
NR
0.0008
0.8
1.42
0.10
0.01
1.69
0.17
0.00
0.21
0.00
0.02
0.03
3.12
NR
0.03
13.15
5.11
0.01
3.18
O.01
5.15
0.36
0.16
4.85
O.01
0.06
0.09
0.01
0.01
NR
0.03
O.01
1.49 ±0.21
2.58 ±1.13
O.01±O.01
1.11±0.17
0.14 ±0.03
0.01 ±0.01
0.68 ±0.07
0.06 ±0.02
0.11 ±0.03
0.26 ±0.08
3.28
NR
4.33
8.67
4.24
0.67
10.17
2.76
24.59
2.82
0.17
129.14
0.03
0.04
0.07
0.02
0.02
NR
0.14
O.01
to
I
-------
Table 27-7. Chronic Risk Summary for the Monitoring Sites in Texas (Continued)
Pollutant
1 ,2-Dichloroethane
Formaldehyde
Hexachloro-l,3-butadiene
Manganese
Nickel
1, 1,2,2-Tetrachloroethane
Tetrachloroethylene
1 , 1 ,2-Trichloroethane
Vinyl Chloride
Cancer
URE
Oig/m3)
0.000026
5.5E-09
0.000022
NR
0.00016
0.000058
0.0000059
0.000016
0.0000088
Noncancer
RfC
Oig/m3)
2.4
0.0098
0.09
0.00005
0.000065
NR
0.27
0.4
0.1
1999 NATA
Modeled
Concentration
(Hg/m3)
0.04
1.52
0.00
0.18
0.19
0.05
0.23
0.00
0.05
Cancer Risk
(in-a-
million)
0.93
0.01
0.03
NR
0.03
3.12
1.36
<0.01
0.46
Noncancer
Risk (HQ)
<0.01
0.15
<0.01
0.01
0.01
NR
0.01
O.01
0.01
2005/2006 UATMP
Annual
Average
(Hg/m3)
0.06 ± 0.02
3.01 ±0.45
0.50 ±0.23
0.01 ±0.01
0.01 ±0.01
0.10 ±0.03
0.20 ±0.08
0.06 ±0.03
0.03 ±0.01
Cancer
Risk (in-a-
million)
1.63
0.02
10.91
NR
0.23
5.72
1.16
0.98
0.26
Noncancer
Risk (HQ)
O.01
0.31
0.01
0.11
0.02
NR
0.01
O.01
0.01
Webberville Road, Austin, Texas (WETX) - Census Tract ID 48453000802
Acetaldehyde
Acrolein
Acrylonitrile
Arsenic
Benzene
1,3-Butadiene
Cadmium
Carbon Tetrachloride
Chloromethylbenzene
1 ,2-Dibromoethane
p-Dichlorobenzene
1,2-Dichloroethane
Formaldehyde
Hexachloro-l,3-butadiene
Hexavalent Chromium
Manganese
Nickel
1 , 1 ,2,2-Tetrachloroethane
0.0000022
NR
0.000068
0.0043
0.0000078
0.00003
0.0018
0.000015
0.000049
0.00022
0.000011
0.000026
5.5E-09
0.000022
0.012
NR
0.00016
0.000058
0.009
0.00002
0.002
0.00003
0.03
0.002
0.00002
0.04
NR
0.0008
0.8
2.4
0.0098
0.09
0.0001
0.00005
0.000065
NR
1.57
0.13
0.00
0.01
1.53
0.16
0.00
0.22
0.00
0.02
0.04
0.04
1.65
0.00
0.00
0.19
0.00
0.05
3.46
NR
0.01
0.02
11.92
4.73
0.01
3.24
0.01
5.23
0.39
0.94
0.01
0.03
0.18
NR
0.03
3.18
0.17
6.64
O.01
0.01
0.05
0.08
0.01
0.01
NR
0.03
O.01
0.01
0.17
0.01
0.01
O.01
0.01
NR
1.69 ±0.35
4.12 ±1.25
0.19±0.12
0.01 ±0.01
1.88 ±0.32
0.33 ±0.09
0.01 ±0.01
0.67 ± 0.04
0.06 ±0.03
0.10 ±0.02
0.40 ±0.08
0.06 ±0.01
2.72 ±0.54
0.49 ±0.23
0.01 ±0.01
0.01 ±O.01
0.01 ±0.01
0.09 ±0.02
3.73
NR
12.98
4.48
14.70
9.93
0.25
10.02
2.98
22.73
4.44
1.49
0.01
10.82
0.36
NR
0.21
5.10
0.19
206.23
0.10
0.03
0.06
0.17
0.01
0.02
NR
0.13
O.01
0.01
0.28
0.01
0.01
0.14
0.02
NR
to
to
-------
Table 27-7. Chronic Risk Summary for the Monitoring Sites in Texas (Continued)
Pollutant
Tetrachloroethylene
Xylenes
Cancer
URE
Oig/m3)
0.0000059
NR
Noncancer
RfC
Oig/m3)
0.27
0.1
1999 NATA
Modeled
Concentration
(Hg/m3)
0.21
2.10
Cancer Risk
(in-a-
million)
1.25
NR
Noncancer
Risk (HQ)
<0.01
0.02
2005/2006 UATMP
Annual
Average
(Hg/m3)
0.19 ±0.06
9.43 ± 4.22
Cancer
Risk (in-a-
million)
1.14
NR
Noncancer
Risk (HQ)
O.01
0.09
El Paso, Texas (YDSP) - Census Tract ID 48141003902
Acrolein
Benzene
1,3-Butadiene
Carbon Tetrachloride
p-Dichlorobenzene
Hexachloro-l,3-butadiene
Tetrachloroethylene
Trichloroethylene
Xylenes
NR
0.0000078
0.00003
0.000015
0.000011
0.000022
0.0000059
0.000002
NR
0.00002
0.03
0.002
0.04
0.8
0.09
0.27
0.6
0.1
0.04
0.87
0.09
0.21
0.03
0.00
0.14
0.07
0.91
NR
6.79
2.63
3.17
0.34
0.03
0.81
0.13
NR
1.78
0.03
0.04
0.01
<0.01
0.01
0.01
O.01
0.01
1.14 ±1.00
2.39 ±0.30
0.33 ±0.06
0.59 ±0.04
0.45 ±0.12
0.74 ±0.17
0.32 ±0.31
0.18 ±0.04
7.32 ±1.10
NR
18.65
9.79
8.92
4.93
16.17
1.89
0.37
NR
56.81
0.08
0.16
0.01
O.01
0.01
0.01
O.01
0.07
to
* Metals sampled with PMi0 filters
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be made.
-------
• Hexachloro-1,3-butadiene poses the highest cancer risk of the pollutants of interest
for MUTX, PITX, and RRTX. This pollutant has the second highest cancer risk for
TRTX, following 1,2-dibromoethane.
• 1,2-Dibromoethane was only detected twice at TRTX, and the annual average was
calculated using the 1/2 MDL substitution for non-detects, as outlined in Section
3.3.5. While the resulting cancer risk (24.59 in-a-million) appears high, the annual
average from which the cancer risk was based (0.11 |ig/m3) was less than the MDL of
this pollutant (0.25 |ig/m3).
• Other pollutants with higher cancer risks include carbon tetrachloride and benzene.
• The only pollutant with noncancer HQs greater than 1.0 was acrolein. The noncancer
risks of this pollutant for these four sites were the highest of all UATMP sites, and
ranged from 125.65 (for PITX) to 230.36 (for RRTX).
• All of the other noncancer risks for the remaining pollutants were less than 0.40.
The following observations can be made about WETX for the annual averages-based
risks from Table 27-7:
• Xylenes had the highest annual averages for WETX, followed by acrolein and
formaldehyde. However, 1,2-dibromoethane had the highest cancer risk for WETX.
This pollutant was detected five times at WETX.
• Other pollutants with cancer risks greater than 1 in-a-million for WETX include
benzene, acrylonitrile, hexachloro-l,3-butadiene, and carbon tetrachloride.
• Similar to the other Austin sites, acrolein was the only pollutant with a noncancer HQ
greater than 1.0 for WETX and its value was similarly high.
The following observations can be made about YDSP for the annual averages-based risks
from Table 27-7:
• Xylenes had the highest annual averages for YDSP, followed by benzene and
acrolein.
• Benzene had the highest cancer risk for this site (18.65 in-a-million), although
xylenes have no cancer risk URE.
• Hexachloro-1,3-butadiene also had a cancer risk greater than 10 in-a-million (16.17
in-a-million).
27-54
-------
• Similar to the Austin sites, acrolein was the only pollutant with a noncancer HQ
greater than 1.0. Although its HQ was significantly lower than the Austin sites, this
pollutant still had one of the higher noncancer HQs of the UATMP sites.
The following observations can be made for the NATA-modeled risks from Table 27-7:
• Benzene had the highest NATA-modeled cancer risk for all of the Texas sites, and
these risks tended to be slightly higher than those calculated from the annual averages
for the Austin sites. The modeled concentrations for benzene also tended to be higher
than the annual averages.
• Acrolein was the only pollutant with a noncancer HQ greater than 1.0 according to
NAT A, but the noncancer HQ was significantly lower, ranging from 1.78 for YDSP
to6.64forWETX.
27.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 27-8 and 27-9 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 27-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 27-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. In addition, the highest cancer and noncancer risks based on the annual
average are limited to those pollutants failing at least one screen.
The following observations can be made from Table 27-8:
• Benzene was the highest emitted pollutant with cancer risk factor in all three Texas
Counties, had the highest toxicity-weighted emissions in all three counties, and had
one of the top five highest cancer risks for all six Texas sites.
27-55
-------
Table 27-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Texas
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on
Annual Average Concentration
(Site-Specific)
Pollutant
Cancer
Risk
(in-a-
million)
Murchison Middle School, Austin, Texas (MUTX) - Travis County
Benzene
Formaldehyde
Tetrachloroethylene
Dichloromethane
Acetaldehyde
1,3 -Butadiene
1 , 3 -Dichloropropene
Trichloroethylene
/>-Dichlorobenzene
Naphthalene
579.83
239.99
118.95
94.78
86.05
68.34
64.30
28.89
20.54
17.22
Benzene
1,3 -Butadiene
Lead
Tetrachloroethylene
Naphthalene
1 , 3 -Dichloropropene
£>-Dichlorobenzene
Acetaldehyde
Poly cyclic Organic Matter as 15 -PAH
Polycyclic Organic Matter as 7-PAH
4.52E-03
2.05E-03
8.08E-04
7.02E-04
5.86E-04
2.57E-04
2.26E-04
1.89E-04
1.82E-04
1.82E-04
Hexachloro- 1 , 3 -butadiene
Carbon Tetrachloride
Benzene
Acrylonitrile
Acetaldehyde
Chloromethylbenzene
£>-Dichlorobenzene
1,3 -Butadiene
Arsenic
Tetrachloroethylene
12.34
9.50
7.31
4.97
3.15
2.81
2.43
2.27
2.04
1.60
Pickle Research Center, Austin, Texas (PITX) - Travis County
Benzene
Formaldehyde
Tetrachloroethylene
Dichloromethane
Acetaldehyde
1,3 -Butadiene
1 ,3 -Dichloropropene
Trichloroethylene
£>-Dichlorobenzene
Naphthalene
579.83
239.99
118.95
94.78
86.05
68.34
64.30
28.89
20.54
17.22
Benzene
1,3 -Butadiene
Lead
Tetrachloroethylene
Naphthalene
1 ,3 -Dichloropropene
/>-Dichlorobenzene
Acetaldehyde
Polycyclic Organic Matter as 15 -PAH
Polycyclic Organic Matter as 7-PAH
4.52E-03
2.05E-03
8.08E-04
7.02E-04
5.86E-04
2.57E-04
2.26E-04
1.89E-04
1.82E-04
1.82E-04
Hexachloro- 1 , 3 -butadiene
Carbon Tetrachloride
Benzene
Acetaldehyde
£>-Dichlorobenzene
1,3 -Butadiene
Arsenic
Tetrachloroethylene
Nickel
Trichloroethylene
16.50
10.20
6.22
3.14
2.57
2.15
1.95
0.65
0.20
0.18
to
-------
Table 27-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Texas (Continued)
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on
Annual Average Concentration
(Site-Specific)
Pollutant
Cancer
Risk
(in-a-
million)
Travis High School, Austin, Texas (TRTX) - Travis County
Benzene
Formaldehyde
Tetrachloroethylene
Dichloromethane
Acetaldehyde
1,3 -Butadiene
1 ,3 -Dichloropropene
Trichloroethylene
/>-Dichlorobenzene
Naphthalene
579.83
239.99
118.95
94.78
86.05
68.34
64.30
28.89
20.54
17.22
Benzene
1,3 -Butadiene
Lead
Tetrachloroethylene
Naphthalene
1 ,3 -Dichloropropene
£>-Dichlorobenzene
Acetaldehyde
Poly cyclic Organic Matter as 15 -PAH
Polycyclic Organic Matter as 7-PAH
4.52E-03
2.05E-03
8.08E-04
7.02E-04
5.86E-04
2.57E-04
2.26E-04
1.89E-04
1.82E-04
1.82E-04
1 ,2-Dibromoethane
Hexachloro- 1 , 3 -butadiene
Carbon Tetrachloride
Benzene
1, 1,2,2-Tetrachloroethane
Arsenic
1,3 -Butadiene
Acetaldehyde
/>-Dichlorobenzene
Chloromethylbenzene
24.59
10.91
10.17
8.67
5.72
4.33
4.24
3.28
2.82
2.76
Webberville Road, Austin, Texas (WETX) - Travis County
Benzene
Formaldehyde
Tetrachloroethylene
Dichloromethane
Acetaldehyde
1,3 -Butadiene
1 ,3 -Dichloropropene
Trichloroethylene
£>-Dichlorobenzene
Naphthalene
579.83
239.99
118.95
94.78
86.05
68.34
64.30
28.89
20.54
17.22
Benzene
1,3 -Butadiene
Lead
Tetrachloroethylene
Naphthalene
1 ,3 -Dichloropropene
/>-Dichlorobenzene
Acetaldehyde
Polycyclic Organic Matter as 15 -PAH
Polycyclic Organic Matter as 7-PAH
4.52E-03
2.05E-03
8.08E-04
7.02E-04
5.86E-04
2.57E-04
2.26E-04
1.89E-04
1.82E-04
1.82E-04
1 ,2-Dibromoethane
Benzene
Acrylonitrile
Hexachloro- 1 , 3 -butadiene
Carbon Tetrachloride
1,3 -Butadiene
1 , 1 ,2,2-Tetrachloroethane
Arsenic
£>-Dichlorobenzene
Acetaldehyde
22.73
14.70
12.98
10.82
10.02
9.93
5.10
4.48
4.44
3.73
to
-------
Table 27-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for the
Monitoring Sites in Texas (Continued)
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on
Annual Average Concentration
(Site-Specific)
Pollutant
Cancer
Risk
(in-a-
million)
Round Rock, Texas (RRTX) - Williamson County
Benzene
Formaldehyde
Dichloromethane
Acetaldehyde
1 , 3 -Dichloropropene
1,3 -Butadiene
Tetrachloroethylene
£>-Dichlorobenzene
Naphthalene
Trichloroethylene
160.04
76.00
40.79
29.76
20.68
18.85
18.08
6.50
5.57
5.03
Benzene
Lead
1,3 -Butadiene
Naphthalene
Tetrachloroethylene
1 ,3 -Dichloropropene
Polycyclic Organic Matter as 15-PAH
£>-Dichlorobenzene
Acetaldehyde
Hexavalent Chromium
1.25E-03
8.84E-04
5.65E-04
1.89E-04
1.07E-04
8.27E-05
7.27E-05
7.15E-05
6.55E-05
6.20E-05
Hexachloro- 1 ,3 -butadiene
Carbon Tetrachloride
Benzene
Acrylonitrile
Acetaldehyde
£>-Dichlorobenzene
Chloromethylbenzene
1,3 -Butadiene
Arsenic
Tetrachloroethylene
12.75
9.88
7.66
4.08
3.24
2.93
2.60
2.38
2.10
1.52
El Paso, Texas (YDSP) - El Paso County
Benzene
Formaldehyde
Dichloromethane
Tetrachloroethylene
Acetaldehyde
1 ,3 -Dichloropropene
1,3 -Butadiene
Trichloroethylene
£>-Dichlorobenzene
Naphthalene
420.95
164.95
78.73
67.21
63.75
55.70
40.17
19.20
17.11
10.29
Benzene
1,3 -Butadiene
Lead
Tetrachloroethylene
Naphthalene
1 ,3 -Dichloropropene
Arsenic
£>-Dichlorobenzene
Acetaldehyde
Polycyclic Organic Matter as 15-PAH
3.28E-03
1.21E-03
4.19E-04
3.97E-04
3.50E-04
2.23E-04
1.90E-04
1.88E-04
1.40E-04
1.18E-04
Benzene
Hexachloro- 1 , 3 -butadiene
1,3 -Butadiene
Carbon Tetrachloride
£>-Dichlorobenzene
Tetrachloroethylene
Trichloroethylene
18.65
16.17
9.79
8.92
4.93
1.89
0.37
to
oo
-------
Table 27-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Texas
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations (Site-
Specific)
Pollutant
Noncancer
Risk
(HQ)
Murchison Middle School, Austin, Texas (MUTX) - Travis County
Toluene
Xylenes
Benzene
Hexane
Methanol
Ethylbenzene
Formaldehyde
1,1,1 -Trichloroethane
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
1,762.66
1,128.96
579.83
347.59
299.90
268.08
239.99
206.47
167.89
157.17
Acrolein
2,4-Toluene Diisocyanate
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Acetaldehyde
Naphthalene
Cyanide
Toluene
588,285.13
63,744.61
34,171.65
24,488.63
19,327.66
11,289.60
9,561.34
5,741.14
4,433.78
4,406.66
Acrolein
Formaldehyde
Acetaldehyde
Manganese
1,3 -Butadiene
Acrylonitrile
Benzene
Nickel
Carbon Tetrachloride
Arsenic
186.97
0.29
0.16
0.10
0.04
0.04
0.03
0.02
0.02
0.02
Pickle Research Center, Austin, Texas (PITX) - Travis County
Toluene
Xylenes
Benzene
Hexane
Methanol
Ethylbenzene
Formaldehyde
1,1,1 -Trichloroethane
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
1,762.66
1,128.96
579.83
347.59
299.90
268.08
239.99
206.47
167.89
157.17
Acrolein
2,4-Toluene Diisocyanate
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Acetaldehyde
Naphthalene
Cyanide
Toluene
588,285.13
63,744.61
34,171.65
24,488.63
19,327.66
11,289.60
9,561.34
5,741.14
4,433.78
4,406.66
Acrolein
Formaldehyde
Acetaldehyde
Manganese
1,3 -Butadiene
Benzene
Nickel
Carbon Tetrachloride
Arsenic
Hexachloro- 1 , 3 -butadiene
125.65
0.29
0.16
0.12
0.04
0.03
0.02
0.02
0.02
0.01
to
-------
Table 27-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Texas (Continued)
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations (Site-
Specific)
Pollutant
Noncancer
Risk
(HQ)
Travis High School, Austin, Texas (TRTX) - Travis County
Toluene
Xylenes
Benzene
Hexane
Methanol
Ethylbenzene
Formaldehyde
1,1,1 -Trichloroethane
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
1,762.66
1,128.96
579.83
347.59
299.90
268.08
239.99
206.47
167.89
157.17
Acrolein
2,4-Toluene Diisocyanate
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Acetaldehyde
Naphthalene
Cyanide
Toluene
588,285.13
63,744.61
34,171.65
24,488.63
19,327.66
11,289.60
9,561.34
5,741.14
4,433.78
4,406.66
Acrolein
Formaldehyde
Acetaldehyde
1 ,2-Dibromoethane
Manganese
1,3 -Butadiene
Benzene
Arsenic
Nickel
Cadmium
129.14
0.31
0.17
0.14
0.11
0.07
0.04
0.03
0.02
0.02
Webberville Road, Austin, Texas (WETX) - Travis County
Toluene
Xylenes
Benzene
Hexane
Methanol
Ethylbenzene
Formaldehyde
1,1,1 -Trichloroethane
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
1,762.66
1,128.96
579.83
347.59
299.90
268.08
239.99
206.47
167.89
157.17
Acrolein
2,4-Toluene Diisocyanate
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Acetaldehyde
Naphthalene
Cyanide
Toluene
588,285.13
63,744.61
34,171.65
24,488.63
19,327.66
11,289.60
9,561.34
5,741.14
4,433.78
4,406.66
Acrolein
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Manganese
1 ,2-Dibromoethane
Acrylonitrile
Xylenes
Benzene
Arsenic
206.23
0.28
0.19
0.17
0.14
0.13
0.10
0.09
0.06
0.03
to
-------
Table 27-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs for the
Monitoring Sites in Texas (Continued)
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations (Site-
Specific)
Pollutant
Noncancer
Risk
(HQ)
Round Rock, Texas (RRTX) - Williamson County
Toluene
Xylenes
Benzene
Methanol
Hexane
Formaldehyde
Ethylbenzene
Methyl Isobutyl Ketone
1,1,1 -Trichloroethane
Methyl Ethyl Ketone
493.03
313.61
160.04
95.79
86.53
76.00
71.81
71.36
62.64
57.77
Acrolein
1,3 -Butadiene
Formaldehyde
(Including Benzene From Gasoline)
2,4-Toluene Diisocyanate
Acetaldehyde
Xylenes
Naphthalene
Glycol Ethers
Toluene
228,165.45
9,424.62
7,754.92
5,334.50
4,380.41
3,306.43
3,136.12
1,856.88
1,333.96
1,232.57
Acrolein
Formaldehyde
Acetaldehyde
Manganese
1,3 -Butadiene
Benzene
Acrylonitrile
Nickel
Carbon Tetrachloride
Arsenic
230.36
0.34
0.16
0.11
0.04
0.03
0.03
0.02
0.02
0.02
El Paso, Texas (YDSP) - El Paso County
Toluene
Xylenes
1,1,1 -Trichloroethane
Benzene
Methanol
Hexane
Methyl Ethyl Ketone
Formaldehyde
Ethylbenzene
Methyl Isobutyl Ketone
1,174.89
692.74
628.41
420.95
252.37
223.33
199.61
164.95
159.31
105.48
Acrolein
1,3 -Butadiene
2,4-Toluene Diisocyanate
Formaldehyde
Chlorine
Benzene
Manganese
Acetaldehyde
Xylenes
Glycol Ethers
384,705.08
20,086.92
18,598.29
16,831.76
14,160.00
14,031.79
13,529.83
7,083.26
6,927.37
4,450.35
Acrolein
1,3 -Butadiene
Benzene
Xylenes
Carbon Tetrachloride
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
p-Dichlorobenzene
Trichloroethylene
56.81
0.16
0.08
0.07
0.01
0.01
<0.01
0.01
O.01
to
-------
• While hexachloro-1,3 -butadiene and carbon tetrachloride had some of the highest
annual average-based cancer risks for all the sites, these pollutants did not rank in the
top 10 for mass emissions or for toxi city-weighted emissions.
• Although lead and 1,3-butadiene also had high toxicity-weighted emissions, only 1,3-
butadiene appeared on all three top 10 lists.
The following observations can be made from Table 27-9:
• Like many UATMP counties, toluene and xylenes had the highest emissions in
Travis, Williamson, and El Paso Counties for pollutants with noncancer risk factors.
These two pollutants also had some of the highest toxicity-weighted emissions in
Travis and Williamson Counties. For El Paso County, toluene did not appear on the
highest toxicity-weighted emissions list.
• Acrolein had the highest toxicity-weighted emissions for all three counties, but did
not appear on the list of highest emitted pollutants. Acrolein also had the highest
noncancer risk for each of the Texas sites.
• Formaldehyde, which had the second highest noncancer risk based on annual
averages for the Austin sites (YDSP did not sample carbonyls), also appeared on each
of the top 10 emissions and toxicity-weighted emissions lists.
Texas Pollutant Summary
The pollutants of interest common to each of the Texas sites were acrolein, benzene, 1,3-
butadiene, carbon tetrachloride, andp-dichlorobenzene.
Acrolein had the highest daily average for all five Austin sites, while total xylenes had the
highest at the El Paso site.
Acrolein exceeded the short-term risk factors at all six Texas sites.
27-62
-------
28.0 Site in Utah
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Bountiful, Utah (BTUT), located just north of Salt Lake City. Figure 28-1 is a
topographical map showing the monitoring site in its urban location. Figure 28-2 identifies point
source emission locations within 10 miles of this site as reported in the 2002 NEI for point
sources. Most of the point sources near the Bountiful site are located south of the site. A
number of these sources are involved in fuel combustion processes, petroleum and natural gas
production and refining, and fabricated metal product production.
The Salt Lake City area has a semi-arid continental climate, with large seasonal
variations. The area is dry, located on the west side of the Wasatch Mountains, and the Great
Salt Lake tends to have a moderating influence on the city's temperature. Moderate winds flow
out of the southeast on average (Ruffner and Bair, 1987).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the BTUT monitoring site is Salt Lake City International Airport (WBAN 24127). Table 28-1
presents average meteorological conditions of temperature (average maximum and average),
moisture (average dew point temperature, average wet-bulb temperature, and average relative
humidity), pressure (average sea level pressure), and wind information (average scalar wind
speed) for the entire year and on days samples were collected. Also included in Table 28-1 is the
95 percent confidence interval. As shown in Table 28-1, average meteorological conditions on
sampling days were representative of average weather conditions throughout the year.
28.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Michigan
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
28-1
-------
Figure 28-1. Bountiful, Utah (BTUT) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
28-2
-------
Figure 28-2. Facilities Located Within 10 Miles of BTUT
Davis. County
Morgan
County
-------
Table 28-1. Average Meteorological Conditions near the Monitoring Site in Utah
Site
BTUT
WBAN
24127
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(»F)
64.18
±2.16
64.40
±5.12
Average
Temperature
(°F)
53.77
±1.96
53.42
±4.63
Average
Dew Point
Temperature
(°F)
33.13
±1.02
33.10
±2.39
Average
Wet Bulb
Temperature
(°F)
43.25
±1.28
43.10
±3.05
Average
Relative
Humidity
(%)
52.65
±1.90
52.91
±4.25
Average
Sea Level
Pressure
(mb)
1015.71
±0.82
1016.38
±2.12
Average
Scalar Wind
Speed
(kt)
7.38
±0.29
7.25
±0.79
to
oo
-------
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. The BTUT monitoring site sampled for
carbonyls, SNMOC, VOC, and metals. Table 28-2 presents the seventeen pollutants that failed
at least one screen at BTUT.
Table 28-2. Comparison of Measured Concentrations and EPA Screening
Values for the Utah Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
%of
Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Bountiful, UT- BTUT
Acetaldehyde
Formaldehyde
Benzene
Carbon Tetrachloride
Arsenic (PM10)
1,3 -Butadiene
Acrolein
Manganese (PM10)
Tetrachloroethylene
Cadmium (PM10)
/>-Dichlorobenzene
Hexachloro- 1 ,3 -butadiene
1 ,2-Dichloroethane
Hexavalent Chromium
Xylenes
Acrylonitrile
Nickel (PM10)
Total
60
60
59
58
52
51
43
36
26
10
6
2
2
2
1
1
1
470
60
60
59
59
58
53
43
58
49
58
33
2
2
54
59
1
58
766
100.00
100.00
100.00
98.31
89.66
96.23
100.00
62.07
53.06
17.24
18.18
100.00
100.00
3.70
1.69
100.00
1.72
61.36
12.77
12.77
12.55
12.34
11.06
10.85
9.15
7.66
5.53
2.13
1.28
0.43
0.43
0.43
0.21
0.21
0.21
12.77
25.53
38.09
50.43
61.49
72.34
81.49
89.15
94.68
96.81
98.09
98.51
98.94
99.36
99.57
99.79
100.00
The following observations are shown in Table 28-2:
• A total of 470 measured concentrations failed screens.
• The risk screening process for BTUT resulting in 10 pollutants of interest:
acetaldehyde (60 failed screens), formaldehyde (60), benzene (59), carbon
tetrachloride (58), arsenic (52), 1,3-butadiene (51), acrolein (43), manganese (36),
tetrachloroethylene (26), and cadmium (10).
28-5
-------
• Of the 10 pollutants of interest, acetaldehyde, acrolein, benzene, and formaldehyde
had 100 percent of their measured detections fail screens.
28.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 28-3. Annual averages are presented and discussed in further detail in later
sections.
The following observations are shown in Table 28-3:
• Acetaldehyde, arsenic, benzene, formaldehyde, manganese, cadmium, and carbon
tetrachloride were detected in every sample collected at BTUT.
• Among the daily averages, formaldehyde had the highest concentration by mass (5.63
± 0.97 |ig/m3), followed by acetaldehyde (3.37 ± 0.37 |ig/m3) and benzene (1.16 ±
0.14|ig/m3).
• Seasonal averages did not vary much for each pollutant of interest for BTUT, with the
exception of formaldehyde, which was significantly higher, in the summer.
28.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for BTUT was evaluated using ATSDR short-
term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is defined
as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15 to 364
days. It is useful to compare the preprocessed daily measurements to the short-term MRL and
28-6
-------
Table 28-3. Daily and Seasonal Averages for the Pollutants of Interest for the Utah Monitoring Site
Pollutant
#of
Measured
Detections
#
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Hg/m3)
Conf.
Int.
Spring
Avg
(Hg/m3)
Conf.
Int.
Summer
Avg
(Ug/m3)
Conf.
Int.
Autumn
Avg
(Ug/m3)
Conf.
Int.
Bountiful, UT - BTUT
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
1,3 -Butadiene
Cadmium (PM10)
Carbon Tetrachloride
Formaldehyde
Manganese (PM10)
Tetrachloroethylene
60
43
58
59
53
58
59
60
58
49
60
59
58
59
59
58
59
60
58
59
3.37
0.74
0.0007
1.16
0.13
0.0008
0.61
5.63
0.0079
0.21
0.37
0.22
0.0001
0.14
0.03
0.0006
0.05
0.97
0.0012
0.04
2.77
0.35
0.0010
1.63
0.18
0.0015
0.52
3.44
0.0056
0.25
0.46
0.15
0.0005
0.32
0.04
0.0013
0.06
0.49
0.0020
0.08
3.07
NR
0.0005
0.84
0.10
0.0012
0.47
4.58
0.0074
0.11
0.58
NR
0.0001
0.19
0.04
0.0020
0.10
0.86
0.0030
0.05
4.91
0.54
0.0007
0.86
0.05
0.0003
0.70
10.57
0.0104
0.16
0.76
0.15
0.0001
0.11
0.01
0.0001
0.09
2.20
0.0017
0.07
2.73
0.96
0.0006
1.25
0.10
0.0002
0.72
3.99
0.0080
0.18
0.46
0.58
0.0002
0.22
0.02
0.0001
0.10
0.79
0.0017
0.05
to
oo
NR = Not reportable due to low number of measured detections.
-------
REL factors, as well as compare seasonal averages to the intermediate MRL. Of the seventeen
pollutants with at least one failed screen at BTUT, only acrolein exceeded both the acute and
intermediate risk values, and its non-chronic risk is summarized in Table 28-4.
The following observations about acrolein are shown in Table 28-4:
• All forty-three acrolein measured detections were greater than the ATSDR acute
value of 0.11 |ig/m3 and the California REL value of 0.19 |ig/m3.
• The average detected concentration was 0.74 ± 0.22 |ig/m3, which was nearly four
times the California REL value.
• For the intermediate acrolein risk, seasonal averages were compared to the ATSDR
intermediate value of 0.09 |ig/m3. Every seasonal average of acrolein exceeded the
intermediate risk value, although an acrolein spring concentration could not be
calculated due to the low number of measured detections.
For the pollutants that exceeded the acute risk factors, the concentrations were further
examined by developing pollution roses for these pollutants. A pollution rose is a plot of daily
concentration and daily average wind direction. Figure 28-3 is the pollution rose for acrolein for
BTUT.
Observations gleaned from the acrolein pollution rose include:
• All of the acrolein concentrations exceeded the acute risk factors, indicated by a
dashed line (CalEPA REL) and solid line (ATSDR MRL).
• The concentrations on the pollution rose are scattered around the center, a pattern
characteristic of mobile sources, although they tend to occur more often with
northwesterly and southeasterly winds. BTUT is located on the grounds of a high
school, which is located just east of 1-15 (Figure 28-1).
• The highest concentration of acrolein occurred with a south-southeasterly wind.
28.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
28-8
-------
Table 28-4. Non-Chronic Risk Summary for the Utah Monitoring Site
Site
BTUT
Method
TO-15
Pollutant
Acrolein
Daily
Average
(Hg/m3)
0.74
±0.22
ATSDR
Short-
term
MRL
(Hg/m3)
0.11
# of ATSDR
MRL
Exceedances
43
CAL EPA
REL
Acute
(Hg/m3)
0.19
# of CAL
EPA REL
Exceedances
43
ATSDR
Intermediate-
term MRL
(Hg/m3)
0.09
Winter
Average
(Hg/m3)
0.35
±0.15
Spring
Average
(Hg/m3)
NR
Summer
Average
(Hg/m3)
0.54
±0.15
Autumn
Average
(Hg/m3)
0.96
±0.58
NA = Not available due to short sampling duration.
NR = Not reportable due to low number of measured detections.
to
oo
i
VO
-------
Figure 28-3. Acrolein Pollution Rose for BTUT
to
oo
5.0
4.0
3.0
2.0
1.0
2
4-1
c
01
o
O 0.0
O
4-*
I
i 1.0
,2
2.0
3.0
4.0
5.0
NW
W
N
sw
Daily Ava Cone = 0.74 ± 0.22 ua/nr
NE
— CA EPA REL (0.19 |jg/rrr)
— ATSDRMRL(0.11 M9/m3)
SE
5.0
4.0
3.0
2.0
1.0 0.0 1.0
Pollutant Concentration
2.0
3.0
4.0
5.0
-------
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
28.4.1 Pearson Correlation Analysis
Table 28-5 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the BTUT monitoring site.
(Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for BTUT from Table 28-5:
• Acetaldehyde, formaldehyde, and manganese exhibited strong positive correlations
with maximum and average temperatures. This indicates that increasing temperatures
correlate to increasing concentrations of these pollutants.
• Acetaldehyde, formaldehyde, and manganese also exhibited strong positive
correlations with dew point and wet bulb temperature, but strong negative
correlations with relative humidity. While this may seem to be conflicting, each of
these moisture variables is highly dependent on the ambient temperature. (For more
information about the moisture variables, please refer to Section 3.1.6.2.) These
correlations indicate that moisture content is an important factor in the concentrations
of these pollutants at this site.
28.4.2 Composite Back Trajectory Analysis
Figure 28-4 is a composite back trajectory map for the BTUT monitoring site for the days
on which sampling occurred. Each line represents the 24-hour trajectory along which a parcel of
air traveled toward the monitoring site on a sampling day. Each concentric circle around the site
in Figure 28-4 represents 100 miles.
The following observations can be made from Figure 28-4:
• Back trajectories predominantly originated from the south and northwest at BTUT.
• The 24-hour airshed domain was somewhat smaller at BTUT when compared to other
UATMP sites; 67 percent of the trajectories originated within 200 miles of the site
and 84 percent were within 300 miles of the site.
• Some trajectories originated as far away as southern Arizona (> 500 miles).
28-11
-------
Table 28-5. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Utah
Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar Wind
Speed
Bountiful, UT - BTUT
1,3 -Butadiene
Acetaldehyde
Acrolein
Arsenic (PM10)
Benzene
Cadmium (PM10)
Carbon Tetrachloride
Formaldehyde
Manganese (PM10)
Tetrachloroethylene
53
60
43
58
59
58
59
60
58
49
-0.39
0.60
0.16
-0.16
-0.35
-0.06
0.43
0.73
0.65
-0.12
-0.42
0.59
0.16
-0.19
-0.41
-0.06
0.42
0.74
0.62
-0.14
-0.43
0.44
0.17
-0.30
-0.41
-0.08
0.47
0.58
0.38
-0.18
-0.43
0.54
0.17
-0.25
-0.43
-0.06
0.44
0.69
0.55
-0.17
0.28
-0.57
-0.13
0.06
0.32
0.01
-0.27
-0.69
-0.70
0.08
0.37
-0.18
-0.35
0.39
0.50
0.05
-0.15
-0.34
-0.15
0.23
-0.27
-0.05
0.30
-0.38
-0.19
0.26
0.09
0.06
-0.08
0.00
to
oo
-------
Figure 28-4. Composite Back Trajectory Map for BTUT
to
oo
I
-------
28.4.3 Wind Rose Analysis
Hourly wind data from the Salt Lake City International Airport near the BTUT
monitoring site were uploaded into a wind rose software program, WRPLOT (Lakes, 2006).
WRPLOT produces a graphical wind rose from the wind data. A wind rose shows the frequency
of wind directions about a 16-point compass, and uses different shading to represent wind
speeds. Figure 28-5 is the wind rose for the BTUT monitoring site on day that sampling
occurred.
The following observations can be made from Figure 28-5:
• Hourly winds were predominantly out of the south-southeast (15 percent of
observations), southeast (15 percent), and south (13 percent) on sampling days.
• Wind speeds ranged from 7 to 11 knots on sampling days.
• Calm winds (<2 knots) were recorded for 9 percent of the observations.
• Wind speeds greater than 22 knots were only observed with south and south-
southeasterly winds.
28.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; BTEX analysis; and
ethylene-acetylene mobile tracer analysis.
28.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Davis County, UT were obtained
from the Utah State Tax Commission and the U.S. Census Bureau, and are summarized in
Table 28-6. Table 28-6 also includes a vehicle registration to county population ratio (vehicles
per person). In addition, the population within 10 miles of each site is presented. An estimation
of 10-mile vehicle registration was computed using the 10-mile population surrounding the
monitor and the vehicle registration ratio. Finally, Table 28-6 contains the average daily traffic
28-14
-------
Figure 28-5. Wind Rose for BTUT Sampling Days
'NORTH"-*
to
oo
20%
16%
WEST
SOUTH ,-
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
^| 11 - 17
I I 7- 11
I I 4- 7
^1 2- 4
Calms: 9.20W
-------
Table 28-6. Motor Vehicle Information for the Utah Monitoring Site
Site
BTUT
2006 Estimated
County
Population
276,259
Number of
Vehicles
Registered
223,379
Vehicles per Person
(Registration:
Population)
0.81
Population
Within 10 Miles
246,163
Estimated 10
Mile Vehicle
Ownership
199,044
Traffic Data
(Daily Average)
33,310
to
oo
-------
information, which represents the average number of vehicles passing the monitoring sites on the
nearest roadway to each site on a daily basis.
Observations gleaned from Table 28-6 include:
• Compared to other UATMP sites, BTUT's county and 10-mile population is in the
low to mid range, as is its county-level vehicle registration and estimated 10-mile
vehicle registration.
• The average daily traffic count falls in the middle of the range compared to other
UATMP sites.
• The BTUT monitoring site is located in a commercial area and is located in an urban-
city center setting.
28.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compared them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
road, or motor vehicle, emissions.
The BTEX table and figure show the following:
• The benzene-ethylbenzene ratio (4.86 ± 0.34) was slightly higher than the xylenes-
ethylbenzene ratio (4.52 ± 0.19), unlike that of the roadside study.
• Similar to the roadside study, the BTUT toluene-ethylbenzene ratio (8.49 ± 0.44) was
the highest concentration ratio.
28.5.3 Mobile Tracer Analysis
As previously stated, BTUT sampled for SNMOCs in addition to VOCs. Acetylene is a
pollutant that is primarily emitted from mobile sources, while ethylene is emitted from mobile
sources, petroleum refining facilities, and natural gas distribution facilities. Tunnel studies
conducted on mobile sources have found that concentrations of ethylene and acetylene are
typically present in a 1.7 to 1 ratio. (For more information, please refer to Section 3.2.1.3.)
28-17
-------
Table 3-11 shows:
• The ethylene to acetylene ratio for BTUT, 1.30, was somewhat lower than the 1.7
ratio.
• This ratio suggests that while mobile sources may be influencing the air quality at the
Utah monitoring site, there may also be atmospheric chemical processes affecting the
quantities of ethylene in this area. Known sinks of ethylene include reactions with
ozone, as well as soil (NLMb).
28.6 Trends Analysis
For sites that participated in the UATMP prior to 2005, and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. BTUT
has participated in the UATMP since 2003. Figure 28-6 presents the trends analysis results for
formaldehyde, benzene, and 1,3-butadiene for BTUT.
The following observations were made:
• Concentrations of formaldehyde appear to have decreased slightly after having
increased significantly over the prior three year period, as presented in Figure 28-6.
• Concentrations of 1,3-butadiene and benzene both decreased slightly after showing
little change from previous years.
28.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Utah site and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 28-7. The
NATA data is presented for the census tract where the monitoring site is located. Additionally,
the pollutants of interest are bolded.
28-18
-------
to
-------
Table 28-7. Chronic Risk Summary for the Monitoring Site in Utah
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual Average
(Hg/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Bountiful, Utah (BTUT) - Census Tract ID 49011126600
Acet aldehyde
Acrolein
Acrylonitrile
Arsenic*
Benzene
1,3-Butadiene
Cadmium*
Carbon Tetrachloride
£>-Dichlorobenzene
1 ,2-Dichloroethane
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Hexavalent Chromium
Nickel*
Manganese*
Tetrachloroethylene
Xylenes
0.0000022
NR
0.000068
0.0043
0.0000078
0.00003
0.0018
0.000015
0.000011
0.000026
5.5E-09
0.000022
0.012
0.00016
NR
0.0000059
NR
0.009
0.00002
0.002
0.00003
0.03
0.002
0.00002
0.04
0.8
2.4
0.0098
0.09
0.0001
0.000065
0.00005
0.27
0.1
1.15
0.08
<0.01
0.28
1.52
0.11
0.07
0.21
0.03
0.03
1.23
0.01
O.01
0.32
0.29
0.12
2.24
2.53
NR
0.05
1.22
11.88
3.38
0.12
3.16
0.37
0.71
0.01
0.03
0.68
0.05
NR
0.68
NR
0.13
4.05
O.01
0.01
0.05
0.06
0.01
0.01
O.01
0.01
0.13
0.01
O.01
O.01
0.01
O.01
0.02
3. 37 ±0.37
0.58 ±0.18
0.07 ± 0.02
O.01±O.01
1.16±0.14
0.11 ±0.02
0.01 ±0.01
0.61 ±0.05
0.06 ±0.03
0.03 ±0.01
5.63 ±0.97
0.07 ±0.01
O.01±O.01
O.01±O.01
0.01 ±0.01
0.18 ±0.04
3.02 ±0.78
7.41
NR
4.88
3.51
9.09
3.21
0.47
9.08
0.67
0.83
0.03
1.63
0.43
0.15
NR
1.05
NR
0.37
28.77
0.04
0.03
0.04
0.05
0.01
0.02
O.01
0.01
0.57
0.01
O.01
0.01
0.17
O.01
0.03
to
oo
to
o
* Metals sampled were sampled with PM10 filters
BOLD indicates a pollutant of interest
NR = a risk factor is not available and therefore, no risk calculation can be
made.
-------
The following observations can be made from Table 28-7:
• The pollutants with the top 3 annual averages by mass concentration were
formaldehyde (5.63 ± 0.97 |ig/m3), acetaldehyde (3.37 ± 0.37 |ig/m3), and xylenes
(3.02 ± 0.78 |ig/m3); however, the pollutants with the highest cancer risks were not
necessarily these pollutants.
• Benzene and carbon tetrachloride exhibited the highest cancer risks at 9.09 in-a-
million and 9.08 in-a-million, respectively. Other pollutants with cancer risks greater
than 1 in-a-million based on the annual average include: acetaldehyde; acrylonitrile;
arsenic; 1,3-butadiene; hexachloro-1,3-butadiene; and tetrachloroethylene.
• Acrolein was the only pollutant that exhibited a noncancer HQ greater than 1 (28.77).
All other noncancer HQs were less than 0.75.
In addition to the annual averages and risks based on 2006 monitoring data, data from
EPA's 1999 NATA were retrieved and are also presented in Table 28-7. The NATA data are
presented for the census tract where the monitoring site is located.
The census tract information for BTUT is as follows:
• The census tract for is 49011126600.
• This census tract had a population of 5,116, which represents approximately 2.1
percent of the county population in 2000.
The following observations about BTUT from NATA include:
• Although xylenes, benzene, and formaldehyde had the highest NATA-modeled
concentrations, this did not translate to the highest cancer risks.
• Benzene, 1,3-butadiene, and carbon tetrachloride had the highest cancer risks. (Total
xylenes do not have a cancer risk factor.)
• Only benzene had a modeled cancer risk greater than 10 in-a-million (11.88). This
compares favorably with the 2006 benzene cancer risk calculated from the annual
average.
• Acrolein was again the only pollutant that exhibited a modeled noncancer HQ greater
than 1 (4.05), although this was roughly seven times less than the risk based on the
2006 annual average.
• All other NATA-modeled noncancer HQs were less than 0.20.
28-21
-------
28.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 28-8 and 28-9 present a
risk-based assessment of county-level emissions based on cancer and noncancer toxicity,
respectively. Table 28-8 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the 10 pollutants with
the highest cancer risk (in-a-million) as calculated from the annual average. Table 28-9 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be. Secondly, each site sampled for specific types of pollutants. Therefore, the
cancer risks based on each site's annual average is limited to those pollutants for which each
respective site sampled. In addition, the highest cancer and noncancer risks based on annual
averages are limited to those pollutants failing at least one screen.
The following observations can be made from Table 28-8:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor, had the
highest cancer toxicity-weighted emissions, and had the highest cancer risk based on
the 2006 annual average for BTUT.
• Although formaldehyde was the second highest emitted pollutant according to the
2002 NEI, the cancer risk factor was relatively low, so this pollutant was not listed on
either the toxicity-weighted emissions or the annual average-based cancer risk.
• Acetaldehyde, 1,3-butadiene, and tetrachloroethylene each appeared in all three top
10 lists.
• Carbon tetrachloride, which had the second-highest cancer risk based on the annual
average for BTUT, was not emitted in high quantities in Davis County, Utah.
The following observations can be made from Table 28-9:
• Although toluene was the highest emitted pollutant (by mass) with a noncancer risk
factor, it did not rank in the top 10 based on toxicity-weighted emissions or the annual
average-based noncancer risk.
28-22
-------
Table 28-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with
Cancer UREs for BTUT
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(for Davis County)
Pollutant
Emissions
(tpy)
Top 10 Based on Cancer Toxicity-Weighted Emissions
(for Davis County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for BTUT)
Pollutant
Cancer Risk
(in-a-million)
Bountiful, Utah - BTUT
Benzene
Formaldehyde
Dichloromethane
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
£>-Dichlorobenzene
Naphthalene
Trichloroethylene
Poly cyclic Organic Matter as 15 -PAH
227.11
71.13
29.21
27.74
20.87
13.48
5.36
4.48
2.92
1.09
Benzene
1,3 -Butadiene
Naphthalene
Tetrachloroethylene
Acetaldehyde
Poly cyclic Organic Matter as 15 -PAH
p-Dichlorobenzene
Polycyclic Organic Matter as 7-PAH
Acrylonitrile
Polycyclic Organic Matter as non-15-PAH
1.77E-03
6.26E-04
1.52E-04
7.95E-05
6.10E-05
6.02E-05
5.89E-05
4.90E-05
3.05E-05
2.34E-05
Benzene
Carbon Tetrachloride
Acetaldehyde
Acrylonitrile
1,3 -Butadiene
Arsenic
Hexachloro- 1 ,3 -butadiene
Cadmium
Tetrachloroethylene
1 ,2-Dichloroethane
9.09
9.08
7.41
4.88
3.21
3.07
1.63
1.41
1.05
0.83
to
oo
to
-------
Table 28-9. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with
Noncancer RfCs for BTUT
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Davis County)
Pollutant
Emissions
(tpy)
Top 10 Based on Noncancer Toxicity-Weighted
Emissions
(for Davis County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for BTUT)
Pollutant
Noncancer
Risk
(HQ)
Bountiful, Utah - BTUT
Toluene
Xylenes
Benzene
w-Hexane
Ethylbenzene
Methanol
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Formaldehyde
1,1,1 -Trichloroethane
681.49
489.16
227.11
113.93
106.11
93.65
89.92
87.13
71.13
51.76
Acrolein
Hexamethylene Diisocyanate
1,3 -Butadiene
Manganese
Benzene
Formaldehyde
Xylenes
Chlorine
Cyanide
Acetaldehyde
231,458.77
12,645.00
10,436.73
9,087.72
7,570.43
7,258.18
4,891.56
4,710.00
3,915.00
3,082.11
Acrolein
Formaldehyde
Acetaldehyde
Manganese
1,3 -Butadiene
Cadmium
Benzene
Acrylonitrile
Xylenes
Arsenic
28.77
0.57
0.37
0.16
0.05
0.04
0.04
0.04
0.03
0.02
to
oo
to
-------
Acrolein had the highest noncancer toxicity-weighted emissions, and had the highest
noncancer risk based on the 2006 annual average for BTUT, but did not appear in the
list of highest emitted pollutants.
Formaldehyde, benzene, and xylenes each appeared on all three top 10 lists.
Utah Pollutant Summary
• The pollutants of interest at the Utah site were acetaldehyde, acrolein, arsenic, benzene,
1,5'-butadiene, carbon tetrachloride, cadmium, formaldehyde, manganese, and
tetrachloroethylene.
• Formaldehyde had the highest daily average for BTUT. Formaldehyde was highest
during the summer.
• Acrolein exceeded the short-term risk factors at BTUT.
• A comparison of formaldehyde, benzene and 1,3-butadiene concentrations for all years of
UATMP participation showed that concentrations of all three have decreased slightly
since 2005.
28-25
-------
29.0 Site in Vermont
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Underbill, Vermont (UNVT), which is near Burlington. Figure 29-1 is a topographical
map showing the monitoring site in its rural location. Figure 29-2 identifies point source
emission locations within 10 miles of this site that reported to the 2002 NEI for point sources.
UNVT is located near only four point sources; each source is involved in different industrial
activities.
The city of Burlington resides just to the east of Lake Champlain in northwest Vermont.
Lake Champlain has a moderating affect on the city, keeping the city slightly warmer than it
could be given its New England location. Vermont is affected by most storm systems that track
across the country, producing variable weather. Average annual winds come from the south,
ahead of advancing weather systems. However, these storm systems are moderated somewhat
due to the Adirondacks to the west and Green Mountains to the east (Ruffner and Bair, 1987).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the UNVT monitoring site is at Morrisville-Stowe St Airport (WBAN 54771). Table 29-1
presents the average meteorological conditions of temperature (average maximum and average),
moisture (average dew point temperature, average wet-bulb temperature, and average relative
humidity), pressure (average sea level pressure), and wind information (average scalar wind
speed) for the entire year and on days samples were collected. Also included in Table 29-1 is the
95 percent confidence interval. As shown in Table 29-1, average meteorological conditions on
sampling days were representative of average weather conditions throughout the year.
29.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Vermont
monitoring site. As described in Section 3.1.4, the methodology for evaluating pollutants of
29-1
-------
Figure 29-1. Underbill, Vermont (UNVT) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:29,000.
29-2
-------
Figure 29-2. Facilities Located Within 10 Miles of UNVT
Note; Due to facility density and collocation, the total facilities
displayed may noJ represent aW feciNlies within th« area of interest.
Legend
UNVT UATMP site
10 mile radius
I County boundary
Source Category Group (No. of Facilities)
r Integrated Iron & Steel Manufacturing Facility (1 )
x Miscellaneous Manufacturing Industries (1 )
s Surface Coating Processes Industrial Facility (1)
1 Waste Treatment & Disposal Industrial Facility (1 }
29-3
-------
Table 29-1. Average Meteorological Conditions near the Monitoring Site in Vermont
Site
UNVT
WBAN
54771
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
54.80
±1.97
54.39
±4.55
Average
Temperature
(»F)
45.56
±1.79
45.63
±4.21
Average
Dew Point
Temperature
(°F)
36.84
±1.83
37.36
±4.36
Average
Wet Bulb
Temperature
(°F)
41.61
±1.69
41.89
±3.97
Average
Relative
Humidity
(%)
74.40
±1.09
75.60
±2.66
Average
Sea Level
Pressure
(mb)
1015.36
±0.81
1015.52
±1.88
Average
Scalar Wind
Speed
(kt)
3.11
±0.22
2.65
±0.42
to
-k
-------
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. Hexavalent chromium was the only
pollutant sampled for at the UNVT monitoring site. Table 29-2 shows that one measured
detection of hexavalent chromium failed the screen.
Table 29-2. Comparison of Measured Concentrations and EPA Screening Values
at the Vermont Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Underbill, Vermont - UNVT
Hexavalent Chromium
1
22
4.55
100.00
100.00
29.2 Concentration Averages
Three types of concentration averages were calculated for hexavalent chromium: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there are at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 29-3. Annual averages are presented and discussed in further detail in later
sections.
29-5
-------
Table 29-3. Daily and Seasonal Averages for the Pollutants of Interest for the Vermont Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
Underbill, Vermont - UNVT
Hexavalent Chromium
22
59
0.039
0.033
NR
NR
0.015
0.005
0.044
0.049
NR
NR
NR = Not reported due to small number of measured detections.
to
-------
The following observations are shown in Table 29-3:
• The daily average concentration of hexavalent chromium for UNVT was 0.039 ±
0.033 ng/m3.
• Only spring and summer seasonal averages could be calculated due to the low
number of measured detections in the other seasons.
• The high confidence interval for the summer average indicates that this seasonal
average was probably influenced by outliers.
29.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data at UNVT was evaluated using ATSDR short-
term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is defined
as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15 to 364
days. Its is useful to compare the preprocessed daily measurement to the short-term MRL and
REL factors, as well as compare the seasonal averages to the intermediate MRL. None of the
seasonal averages of hexavalent chromium exceeded the intermediate risk value for UNVT.
Acute risk could not be evaluated because hexavalent chromium has no acute risk factors.
29.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
29.4.1 Pearson Correlation Analysis
Table 29-4 presents the summary of Pearson correlation coefficients for hexavalent
chromium and select meteorological parameters at the UNVT monitoring site. (Please refer to
Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered for UNVT from Table 29-4:
• Hexavalent chromium exhibited weak correlations with the meteorological
parameters.
29-7
-------
to
VO
oo
Table 29-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Vermont
Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Underbill, Vermont - UNVT
Hexavalent Chromium
22
0.40
0.31
0.20
0.25
-0.29
0.11
-0.03
-------
• This indicates that concentrations of hexavalent chromium were not influenced by
meteorological conditions at UNVT.
29.4.2 Composite Back Trajectory Analysis
Figure 29-3 is a composite back trajectory map for the UNVT monitoring site for the
days on which sampling occurred. Each line represents the 24-hour trajectory along which a
parcel of air traveled toward the monitoring site on a sampling day. Each concentric circle
around the site in Figure 29-3 represents 100 miles.
The following observations can be made from Figure 29-3:
• Back trajectories originated from a variety of directions at UNVT.
• The 24-hour airshed domain was large at UNVT, with trajectories originating as far
away as northern Canada (> 700 miles). However, the majority of the trajectories
originated within 400 miles of the UNVT monitoring site.
29.4.3 Wind Rose Analysis
Hourly wind data from the Morrisville-Stowe Airport near the UNVT monitoring site
were uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces
a graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
about a 16-point compass, and uses different shading to represent wind speeds. Figure 29-4 is
the wind rose for the UNVT monitoring site on days that sampling occurred.
Observations from Figure 29-4 include:
• Hourly winds were predominantly out of the north (10 percent of observations), south
(8 percent), and north-northwest (7 percent) on sampling days.
• Calm winds (<2 knots) were recorded for 53 percent of the observations.
• For winds greater than 2 knots, wind speeds were mostly from 2 to 4 knots, indicating
that winds tended to be very light on sampling days near UNVT. This is confirmed in
Table 29-1.
29-9
-------
Figure 29-3. Composite Back Trajectory Map for UNVT
to
VO
„".
-------
Figure 29-4. Wind Rose for UNVT Sampling Days
WORTH"---.
to
VO
-------
29.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could
not be performed as ERG did not analyze for VOCs at this site. A mobile tracer analysis could
not be performed as this site did not sample for SNMOC.
29.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration was not available in Chittenden County, Vermont.
Thus, state-level vehicle registration from the Energy Information Administration (EIA) was
allocated to the county-level using the county-level population proportion. County-level
population information was obtained from the U.S. Census Bureau, and is summarized in
Table 29-5. Table 29-5 also includes a vehicle registration to county population ratio (vehicles
per person). In addition, the population within 10 miles of each site is presented. An estimate of
10-mile vehicle registration was computed using the 10-mile population surrounding the
monitors and the vehicle registration ratio. Finally, Table 29-5 contains the average daily traffic
information, which represents the average number of vehicles passing the monitoring sites on the
nearest roadway to each site on a daily basis.
Observations gleaned from Table 29-5 include:
• Compared to other UATMP sites, UNVT's county and 10-mile population and
vehicle registration, as well as daily traffic volume, are in the lowest third of the
range.
29.6 Trends Analysis
A trends analysis could not be performed for UNVT as this site has not participated in the
UATMP for three consecutive years.
29.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
UNVT and where the annual average could be calculated. Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 29-6. In
29-12
-------
Table 29-5. Motor Vehicle Information for the Vermont Monitoring Site
Site
UNVT
2006 Estimated
County Population
150,069
Number of
Vehicles
Registered
122,119
Vehicles per Person
(Registration:
Population)
0.81
Population
Within 10 Miles
33,622
Estimated 10
Mile Vehicle
Ownership
27,360
Traffic Data
(Daily
Average)
1,200
to
VO
-------
Table 29-6. Chronic Risk Summary for the Monitoring Site in Vermont
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Hg/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(Hg/m3)
Cancer Risk (in-
a-million)
Noncancer
Risk (HQ)
Underbill, Vermont (UNVT) - Census Tract ID 500070025900
Hexavalent Chromium
0.012
0.0001
<0.01
0.02
<0.01
<0.01±<0.01
0.22
<0.01
to
VO
-------
addition, data from EPA's 1999 NATA were retrieved and are presented in Table 29-6. The
NATA data are presented for the census tract where the monitoring site is located.
The census tract information for UNVT is as follows:
• The UNVT monitoring site is located in census tract 50007002900.
• The population for the census tract where the UNVT monitoring site is located was
6,037, which represents four percent of Chittenden County's population in 2000.
The following observations can be made for UNVT from Table 29-6:
• Both the NATA-modeled and annual average concentration for hexavalent chromium
were less than 0.01 |ig/m3.
• In terms of cancer risk, the NATA-modeled and calculated cancer risks were both less
than 1 in-a-million, although the annual average-based cancer risk (0.22 in-a-million)
was an order of magnitude greater than the NATA-modeled cancer risk (0.02 in-a-
million).
• Both noncancer hazard quotients were less than 0.01, suggesting very little risk for
noncancer health affects due to hexavalent chromium.
29.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 29-7 and 29-8 present a
risk-based assessment of the county-level emissions based on cancer and noncancer toxicity,
respectively. Table 29-7 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the hexavalent
chromium cancer risk (in-a-million) as calculated from the annual average. Table 29-8 presents
similar information, but identifies the 10 pollutants with the highest noncancer risk (HQ) as
calculated from the annual average. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer table, although the actual value of the
emissions will be.
The following observations can be made from Table 29-7:
• Benzene was the highest emitted pollutant with a cancer risk factor and had the
highest cancer toxicity-weighted emissions for Chittenden County, Vermont.
29-15
-------
Table 29-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs for UNVT
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(for Chittenden County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for Chittenden County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for UNVT)
Cancer Risk
Pollutant (in-a-million)
Underbill, Vermont - UNVT
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Dichloromethane
Tetrachloroethylene
Naphthalene
£>-Dichlorobenzene
Trichloroethylene
Poly cyclic Organic Matter as 15 -PAH
226.79
64.13
22.88
20.93
14.46
7.55
4.68
3.19
1.68
1.68
Benzene
1,3 -Butadiene
Lead
Arsenic
Polycyclic Organic Matter as 7-PAH
Naphthalene
Polycyclic Organic Matter as 15 -PAH
Hexavalent Chromium
Acetaldehyde
Tetrachloroethylene
1.77E-03
6.28E-04
3.98E-04
1.77E-04
1.71E-04
1.59E-04
9.25E-05
5.35E-05
5.03E-05
4.45E-05
Hexavalent Chromium 0.22
to
-------
Table 12-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for UNVT
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for Chittenden County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for Chittenden County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for UNVT)
Noncancer
Risk
Pollutant (HQ)
Underbill, Vermont - UNVT
Toluene
Xylenes
Benzene
Methanol
Ethylbenzene
Formaldehyde
Hexane
Methyl Ethyl Ketone
Ethylene Glycol
Hydrochloric Acid
517.82
379.64
226.79
93.76
86.92
64.13
63.01
38.28
29.24
26.25
Acrolein
Manganese
1,3 -Butadiene
Benzene
Formaldehyde
Chlorine
Xylenes
Acetaldehyde
Nickel
Naphthalene
476,741.53
41,238.62
10,462.70
7,559.79
6,544.11
5,031.08
3,796.43
2,542.15
1,735.32
1,560.36
Hexavalent Chromium O.01
to
-------
• Five of 10 pollutants (benzene, acetaldehyde, tetrachloroethylene, 1,3-butadiene, and
naphthalene) appeared on both the highest emitted list and the highest cancer toxicity-
weighted emissions list, indicating that most of the highest emitted pollutants were
also the most toxic.
• Hexavalent chromium, the only pollutant sampled for at UNVT, had a low cancer risk
based its annual average (0.22 in-a-million). This pollutant ranks 8th on the highest
cancer toxicity-weighted emissions list, but did not appear on the highest emissions
list.
The following observations can be made from Table 29-8:
• Toluene was the highest emitted pollutant with noncancer risk factor in Chittenden
County. But like most other UATMP counties, toluene did not rank in the top 10
pollutants based on toxicity-weighted emissions.
• Xylenes, which had the second highest emissions in Chittenden County, did appear
on the list of pollutants based on toxicity-weighted emissions (seventh).
• Acrolein had the highest noncancer toxicity-weighted emissions, but did not appear in
the list of highest emitted pollutants. Hexavalent chromium did not rank in the top 10
highest emitted pollutants with noncancer risk factors or the 10 highest noncancer
toxicity-weighted emissions in Chittenden County.
Vermont Pollutant Summary
UNVT sampled only for hexavalent chromium. Only one measured detection failed a
screen.
29-18
-------
30.0 Site in Washington
This section presents meteorological, concentration, and spatial trends for the UATMP
site in Seattle, Washington (SEWA). Figure 30-1 is a topographical map showing the
monitoring site in its urban location. Figure 30-2 identifies point source emission locations
within 10 miles of this site that reported to the 2002 NEI for point sources. SEWA is located
near several point sources, which are involved in a variety of activities, including surface coating
processes and fabricated metal products production.
Seattle is located between the Puget Sound and Lake Washington, and is situated between
the Olympic Mountains to the west and the Cascades to the east. The city experiences a mild
climate as the mountains moderate storm systems that move into the Pacific Northwest and both
the mountains and the sound shield the city from the temperature extremes. Although the city is
known for being rainy, the actual precipitation totals tend to be lower compared to many
locations east of the Rocky Mountains (Ruffner and Bair, 1987).
Hourly meteorological data at a weather station near this site were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the SEWA monitoring site is at Boeing Field/King County International Airport (WBAN
24234). Table 30-1 presents the average meteorological conditions of temperature (average
maximum and average), moisture (average dew point temperature, average wet-bulb
temperature, and average relative humidity), pressure (average sea level pressure), and wind
information (average scalar wind speed) for the entire year and on days samples were collected.
Also included in Table 30-1 is the 95 percent confidence interval. As shown in Table 30-1,
average temperatures on sampling days were somewhat cooler than average weather conditions
throughout the year. SEWA sampled in January and February, then missed March through
September, and resumed sampling in November and December. This gap in sampling would
explain the difference in temperature profiles.
30-1
-------
Figure 30-1. Seattle, Washington (SEWA) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:30,000.
30-2
-------
Figure 30-2. Facilities Located Within 10 Miles of SEWA
Note; Due to facility density and croitocation. the total facilities
displayed may not represent all faeiNlies within the area of interest
Legend
SEWA UATMP site
10 mile radius
Source Category Group (No. of Facilities)
* Automotive Repair, Services, & Parking (2)
Business Services Facility (1)
c Chemicals & Allied Products Facility (1)
z Electrical & Electronic Equipment Facility (3)
D Fabricated Metal Products Facility (4)
F Fuel Combustion Industrial Facility (1)
J industrial Machinery & Equipment Facility (2j
?• Integrated Iron & Steel Manufacturing Facility (1)
L Liquids Distribution Industrial Facility (3)
County boundary
B Mineral Products Processing Industrial Facility (3)
p Miscellaneous Processes Industrial Facility (6)
\ Non-ferrous Metals Processing Industrial Facility (1)
2 Nonmetallic Minerals. Except Fuels (1)
4 Production of Organic Chemicals Industrial Facility (1)
u Stone, Clay, Glass. & Concrete Products (1)
s Surface Coating Processes Industrial Facility (5)
T Transportation Equipment (1)
Y Waste Treatment & Disposal Industrial Facility (3)
30-3
-------
Table 30-1. Average Meteorological Conditions near the Monitoring Site in Washington
Site
SEWA
WBAN
24234
Average
Type
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
60.28
±1.25
49.88
± 1.76
Average
Temperature
(»F)
53.10
±1.05
44.31
±1.79
Average
Dew Point
Temperature
(°F)
42.55
±0.86
36.42
±3.43
Average
Wet Bulb
Temperature
(°F)
47.86
±0.83
41.02
±2.05
Average
Relative
Humidity
(%)
70.39
±1.28
76.39
±5.65
Average
Sea Level
Pressure
(mb)
1016.64
±0.74
1017.01
±4.00
Average
Scalar
Wind Speed
(kt)
5.17
±0.24
6.76
±1.55
-------
30.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the SEWA
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. Hexavalent chromium was the only
pollutant sampled for at the SEWA monitoring site. Table 30-2 shows that one measured
detection of hexavalent chromium failed the screen at SEWA.
Table 30-2. Comparison of Measured Concentrations and EPA Screening Values
for the Washington Monitoring Site
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Seattle, Washington - SEWA
Hexavalent Chromium
1
12 | 8.33
100.00
100.00
30.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects were incorporated into the
average. Annual averages were calculated for monitoring sites where sampling began no later
than February and ended no earlier than November. Daily and seasonal average concentrations
are presented in Table 30-3. Annual averages are discussed in further detail in later sections.
30-5
-------
Table 30-3. Daily and Seasonal Averages for the Pollutants of Interest for the Washington Monitoring Site
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(ng/m3)
Conf.
Int.
Winter
Avg
(ng/m3)
Conf.
Int.
Spring
Avg
(ng/m3)
Conf.
Int.
Summer
Avg
(ng/m3)
Conf.
Int.
Autumn
Avg
(ng/m3)
Conf.
Int.
Seattle, Washington - SEWA
Hexavalent Chromium
12
13
0.08
0.06
0.07
0.06
NA
NA
NA
NA
NR
NR
NA= Not available due to the short sampling duration.
NR= Not recorded due to low number of measured detections.
-------
The following observations are shown in Table 30-3:
• The daily average for hexavalent chromium for SEWA was 0.08 ± 0.06 ng/m3.
• Only a winter seasonal average could be calculated due to the low number of
measured detections in the some seasons and the lack of sampling in others.
30.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for SEWA was evaluated using ATSDR
short-term (acute) and intermediate MRL and California EPA acute REL factors. Acute risk is
defined as exposures from 1 to 14 days while intermediate risk is defined as exposures from 15
to 364 days. Its is useful to compare the preprocessed daily measurement to the short-term MRL
and REL factors, as well as compare the seasonal averages to the intermediate MRL. The winter
hexavalent chromium average did not exceed the intermediate risk value. Acute risk could not
be evaluated because hexavalent chromium has no acute risk factors.
30.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
30.4.1 Pearson Correlation Analysis
Table 30-4 presents the summary of Pearson correlation coefficients for hexavalent
chromium and select meteorological parameters for the SEWA monitoring site. (Please refer to
Section 3.1.6 for more information on Pearson Correlations.)
The following observations are gathered from Table 30-4:
• A strong negative correlation was calculated for scalar wind speed (-0.51). This
indicates that decreasing wind speeds lead to increasing concentrations.
• Hexavalent chromium exhibited weak correlations with most of the other
meteorological parameters for SEWA. This indicates that, with the exception of
scalar wind speed, meteorological conditions do not greatly influence hexavalent
chromium concentrations at SEWA.
30-7
-------
Table 30-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the
Washington Monitoring Site
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Seattle, Washington - SEWA
Hexavalent Chromium
12
0.17
0.05
0.20
0.16
0.26
0.12
-0.51
o
i
oo
-------
30.4.2 Composite Back Trajectory Analysis
Figure 30-3 is a composite back trajectory map for the SEWA monitoring site for the
days on which sampling occurred. Each line represents the 24-hour trajectory along which a
parcel of air traveled toward the monitoring site on a sampling day. Each concentric circle
around the site in Figure 30-3 represents 100 miles.
The following observations can be made from Figure 30-3:
• Back trajectories originated from a variety of directions at SEWA, although there was
a lack of trajectories originating from the north.
• The 24-hour airshed domain was large at SEWA, with trajectories originating over
900 miles away. However, most of the trajectories originated within 500 miles of the
site.
• The composite back trajectory map might look much different with a full year of
sampling days.
30.4.3 Wind Rose Analysis
Hourly wind data from the Boeing Field/King County Airport near the SEWA monitoring
site were uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT
produces a graphical wind rose from the wind data. A wind rose shows the frequency of wind
directions about a 16-point compass, and uses different shading to represent wind speeds.
Figure 30-4 is the wind rose for the SEWA monitoring site on days that sampling occurred.
Observations from Figure 30-4 include:
• Hourly winds were predominantly out of the south (26 percent of observations),
south-southeast (21 percent), and southeast (13 percent) on sampling days.
• Wind speeds ranged from 7 to 11 knots on most days that samples were collected.
• Calm winds (<2 knots) were recorded for 16 percent of the total measurements.
30.5 Spatial Characteristics Analysis
The following sub-section describes and discusses the results of the following spatial
analysis: population, vehicle ownership, and traffic data comparisons. A BTEX analysis could
30-9
-------
Figure 30-3. Composite Back Trajectory Map for SEWA
o
-------
Figure 30-4. Wind Rose for SEWA Sampling Days
'NORTH"--
30%
\ \
*X 24%
18%
-------
not be performed as ERG did not analyze for VOCs at this site. A mobile tracer analysis could
not be performed as this site did not sample for SNMOC.
30.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level registration and population information for King County was obtained from
the Washington Department of Licensing and the U.S. Census Bureau, and is summarized in
Table 30-5. Table 30-5 also includes a vehicle registration to county population ratio (vehicles
per person). In addition, the population within 10 miles of each site is presented. An estimate of
10-mile vehicle registration was computed using the 10-mile population surrounding the
monitors and the vehicle registration ratio. Finally, Table 30-5 contains the average daily traffic
information, which represents the average number of vehicles passing the monitoring sites on the
nearest roadway to each site on a daily basis.
Observations gleaned from Table 30-5 include:
• Compared to other UATMP sites, SEWA's county population and vehicle registration
are in the top five sites.
• SEWA's 10-mile population and estimated 10-mile vehicle ownership are in the top
third compared to other UATMP sites.
• The daily traffic volume is in the middle of the range.
30.6 Trends Analysis
A trends analysis could not be performed for SEWA as this site has not participated in the
UATMP for three consecutive years.
30.7 Chronic Risk Analysis
A chronic risk analysis was completed for hexavalent chromium for SEWA. While
SEWA's sampling duration appears to meet the criteria for annual averages provided in
Section 3.3.5, SEWA has a sampling gap from March to September. Therefore, annual averages
could not be calculated and annual average-based cancer and noncancer risks cannot be assessed.
However, data from EPA's 1999 NATA were retrieved and are presented in Table 30-6. The
NATA data are presented for the census tract where the monitoring site is located.
30-12
-------
Table 30-5. Motor Vehicle Information for the Washington Monitoring Site
Site
SEWA
2006 Estimated
County Population
1,826,732
Number of
Vehicles
Registered
1,726,115
Vehicles per Person
(Registration:
Population)
0.94
Population Within
10 Miles
887,100
Estimated 10 Mile
Vehicle
Ownership
838,238
Traffic Data
(Daily Average)
20,000
o
I
OJ
-------
Table 30-6. Chronic Risk Summary for the Monitoring Site in Washington
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Ug/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(Ug/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Seattle, Washington (SEWA) - Census Tract ID 53033010000
Hexavalent Chromium
0.012
0.0001
0.01
7.46
0.01
NA
NA
NA
NA = annual average not available
o
I
£
-------
The census tract information for SEWA is as follows:
• The census tract for SEWA is 53033010000.
• This census tract had a population of 8,139 in 2000 and represents approximately 0.1
percent of the King County population.
The following observations can be made from Table 30-6:
• NATA-modeled cancer risk due to hexavalent chromium for SEWA was 7.46 in-a-
million.
• Noncancer risk due to hexavalent chromium was very low (0.01).
30.8 Toxicity-Weighted Emissions Assessment
Tables 30-7 and 30-8 present a risk-based assessment of county-level emissions based on
cancer and noncancer toxicity, respectively. Table 30-7 presents the 10 pollutants with the
highest emissions from the 2002 NEI and the 10 pollutants with the highest toxicity-weighted
emissions. The 10 pollutants with the highest cancer risk based on annual averages could not be
calculated because there are no annual averages. Table 30-8 presents similar information, but is
based on noncancer risk factors. The pollutants in these tables are limited to those that have
cancer and noncancer risk factors, respectively. As a result, the highest emitted pollutants in the
cancer table may not be the same as the noncancer tables, although the actual value of the
emissions will be.
The following observations can be made from Table 30-7:
• Benzene, formaldehyde, and acetaldehyde had the highest emissions (by mass) in
King County for pollutants with cancer risk factors, but only benzene (which ranked
first) and acetaldehyde (which ranked ninth) were among the pollutants with the top
10 highest cancer toxicity-weighted emissions.
• In addition to acetaldehyde and formaldehyde, 1,3-butadiene, tetrachloroethylene,
naphthalene, />-dichlorobenzene, and POM as 15-PAH were among the highest
emitted and had some of the highest cancer toxicity-weighted emissions. This
indicates that the highest emitted pollutants in King County also tend to be the most
toxic.
30-15
-------
Table 30-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs
for SEWA
Top 10 Total Emissions for Pollutants with Cancer
Risk Factors
(for King County)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(for King County)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(for SEWA)
Cancer Risk
Pollutant (in-a-million)
Seattle, Washington - SEWA
Benzene
Formaldehyde
Acetaldehyde
1,3 -Butadiene
Tetrachloroethylene
Dichloromethane
Naphthalene
Trichloroethylene
£>-Dichlorobenzene
Poly cyclic Organic Matter as 15 -PAH
2,863.10
945.95
336.17
253.92
138.20
114.91
67.06
46.11
37.70
26.68
Benzene
1,3 -Butadiene
Lead
Naphthalene
Poly cyclic Organic Matter as 15 -PAH
Poly cyclic Organic Matter as non-15 PAH
Polycyclic Organic Matter as 7-PAH
Tetrachloroethylene
Acetaldehyde
/>-Dichlorobenzene
2.23E-02
7.62E-03
3.34E-03
2.28E-03
1.47E-03
1.02E-03
9.32E-04
8.15E-04
7.40E-04
4.15E-04
-------
Table 30-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for SEWA
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(for King County)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(for King County)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(for SEWA)
Noncancer
Risk
Pollutant (HQ)
Seattle, Washington - SEWA
Toluene
Xylenes
Benzene
Formaldehyde
Methanol
Ethylbenzene
Hexane
Methyl Ethyl Ketone
Acetaldehyde
Ethylene Glycol
5,803.57
3,841.44
2,863.10
945.95
943.68
908.89
891.06
466.76
336.17
323.63
Acrolein
1,3 -Butadiene
Formaldehyde
Benzene
Xylenes
Acetaldehyde
Naphthalene
Manganese
Glycol Ethers
Toluene
2,782,750.42
126,959.02
96,525.87
95,436.79
38,414.41
37,352.35
22,353.99
18,256.20
14,911.49
14,508.92
-------
The following observations can be made from Table 30-8:
• Like many UATMP counties, toluene and xylenes had the highest emissions in King
County. But unlike many UATMP counties, both of these pollutants were also
among those with the top 10 highest noncancer toxicity-weighted emissions.
• In addition to toluene and xylenes, benzene, acetaldehyde, and formaldehyde also
appeared on both lists.
• Acrolein, which did not have one of the highest total emissions, had the highest
noncancer toxicity-weighted emissions.
Washington Pollutant Summary
• SEWA sampled only for hexavalent chromium. Only one measured detection failed a
screen.
30-18
-------
31.0 Sites in Wisconsin
This section presents meteorological, concentration, and spatial trends for the UATMP
sites in Wisconsin (MAWI and MVWI), located in Madison and Mayville, respectively.
Figure 31-1 and 31-2 are topographical maps showing the monitoring sites in their urban and
rural locations. Figure 31-3 and 31-4 identifies point source emission locations within 10 miles
of the sites as reported in the 2002 NEI for point sources. Figure 31-3 shows that MAWI is
surrounded by a number of point sources, of which the majority is involved in fuel combustion
industries. Figure 31-4 shows that fewer sources surround MVWI, but the majority of them are
also involved in fuel combustion processes.
Madison is located in south-central Wisconsin. Much of the city lies between Lake
Mendota and Lake Monona. Madison's Great Lakes location ensures that the area experiences
frequent weather systems, fairly typical of a continental climate. Temperatures can fluctuate
drastically with potent weather systems, and the frozen lakes offer little moderating effects in the
winter. Spring and summer tend to bring the most precipitation, but Madison also receives an
abundance of snow. Average wind direction depends on season. Summer and fall bring
southerly winds, while northwesterly winds are most common in the winter and spring (Ruffner
and Bair, 1987). The town of Mayville is located to the northwest of Milwaukee. This area
experiences a highly variable, continental climate as weather systems frequently push across the
region. Wintertime temperature extremes are moderated somewhat by the proximity to Lake
Michigan. Lake effect snows can occur with winds with an easterly component, although they
are more common closer to the coast (Ruffner and Bair, 1987).
Hourly meteorological data at weather stations near these sites were retrieved for all of
2006. These data were used to determine how meteorological conditions on sampling days vary
from normal conditions throughout the year. They were also used to calculate correlations of
meteorological data with ambient air concentration measurements. The weather station closest
to the MAWI monitoring site is Dane County Regional - Traux Field Airport (WBAN 14837)
and the weather station closest to the MVWI site is West Bend Municipal Airport (WBAN
04875). Table 31-1 presents average meteorological conditions of temperature (average
31-1
-------
Figure 31-1. Madison, Wisconsin (MAWI) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
31-2
-------
Figure 31-2. Mayville, Wisconsin (MVWI) Monitoring Site
Source: USGS 7.5 Minute Series. Map Scale: 1:24,000.
31-3
-------
Figure 31-3. Facilities Located Within 10 Miles of MAWI
Dane
County
D S
V BB
'• *
1F S
F FS
-F - -
5 2
Legend
•^- MAWI UATMP site ]• 10 mile radius
Source Category Group (No. of Facilities)
* Agricultural Chemicals Production Industrial Facility i
• Business Services Facility (1)
5 Educational Setvices Facility (1)
D Fabricated Metal Products Facility (1)
F Fuel Combustion Industrial Facility (26)
i- Integrated Iron & Steel Manufacturing Facility (1)
L Liquids Distribution Industrial Facility (3)
& Lumber & Wood Products Facility (1)
Note; Due to facility density and collocation, the total facilities
displayed may no} represent aM facilities ™thin the area of interest.
] County boundary
B Mineral Products Processing Industrial Facility (4)
)) * Non-ferrous Metals Processing Industrial Facility (2)
> Pharmaceutical Production Processes Industrial Facility (3)
v Polymers & Resins Production Industrial Facility (1)
R Printing a Publishing Facility (2)
s Surface Coating Processes Industrial Facility (5)
8 Utility Boilers (1)
Waste Treatment & Disposal Industrial Facility (5)
$ Wholesale Trade - Durable Goods (1)
31-4
-------
Figure 31-4. Facilities Located Within 10 Miles of MVWI
Fond du Lac ]
County |
Dodge
County
Washington
County
- -O -
_i * *-
Note; Due to facility density and collocation, the tola! facilities
displayed may nol represent aid facilities within (he area of interest
Legend
TV MVWI UATMP site
10 mile radius
| ] County boundary
Source Category Group (No. of Facilities)
o Fabricated Metal Products Facility (3)
f Fuel Combustion Industrial Facility (7)
1 Integrated Iron & Steel Manufacturing Facility (1)
B Mineral Products Processing Industrial Facility (1)
s Surface Coating Processes Industrial Facility (5)
'-' WSaste Treatment & Disposal Industrial Facility (3)
31-5
-------
Table 31-1. Average Meteorological Conditions near the Monitoring Sites in Wisconsin
Site
MAWI
MVWI
WBAN
14837
04875
Average
Type
All 2006
Sampling
Day
All 2006
Sampling
Day
Average
Maximum
Temperature
(°F)
57.35
±1.97
35.75
±3.68
56.30
±1.96
56.64
±4.85
Average
Temperature
(°F)
49.05
± 1.85
30.13
±3.44
48.41
±1.79
48.54
±4.30
Average
Dew Point
Temperature
(OF)
39.25
± 1.82
24.26
±4.52
39.85
±1.74
39.30
±3.97
Average
Wet Bulb
Temperature
(»F)
44.40
± 1.69
28.09
±3.68
44.36
±1.64
44.10
±3.80
Average
Relative
Humidity
(%)
71.52
± 1.21
79.61
±5.61
74.90
±1.21
73.57
±3.27
Average
Sea Level
Pressure
(mb)
1015.66
±0.75
1010.26
±5.23
NA1
NA1
Average
Scalar Wind
Speed
(kt)
6.58
±0.27
6.99
±1.58
5.48
±0.30
5.69
±0.74
Sea level pressure was not recorded at the West Bend Airport.
-------
maximum and average), moisture (average dew point temperature, average wet-bulb
temperature, and average relative humidity), pressure (average sea level pressure), and wind
information (average scalar wind speed) for the entire year and on days samples were collected.
Also included in Table 31-1 is the 95 percent confidence interval for each parameter. As shown
in Table 31-1, average meteorological conditions on sampling days near MVWI were fairly
representative of average weather conditions throughout the year, but this does not appear to be
the case for MAWI. Temperatures on sampling days near MAWI seem much colder because this
site only sampled through the end of February; therefore, the only the coldest months were
captured.
31.1 Risk Screening and Pollutants of Interest
Risk screening was completed to identify the pollutants of interest for the Wisconsin
monitoring sites. As described in Section 3.1.4, the methodology for evaluating pollutants of
interest is a modification of guidance developed by EPA Region 4 (EPA, 2006d). Each
measured pollutant concentration was compared to a risk screening value. A total of 81 HAPs
are listed in the EPA guidance as having risk screening values. If the daily concentration value
was greater than the risk screening value, then the measured concentration "failed the screen."
Pollutants of interest are those in which the individual pollutant's total failed screens contribute
to the top 95 percent of the site's total failed screens. The MAWI site sampled for carbonyls and
VOC, and the MVWI site sampled for hexavalent chromium only. Table 31-2 presents the
pollutants that failed at least one screen at MAWI and MVWI.
The following observations are shown in Table 31-2:
• A total of 42 measured concentrations failed screens at MAWI.
• The pollutants of interest for MAWI were benzene (8 failed screens), acetaldehyde
(8), carbon tetrachloride (8), formaldehyde (6), 1,3-butadiene (6), and hexachloro-
1,3-butadiene (4).
• Of the six pollutants of interest for MAWI, acetaldehyde, benzene, carbon
tetrachloride, and hexachloro-1,3-butadiene failed 100 percent of the screens.
31-7
-------
Table 31-2. Comparison of Measured Concentrations and EPA Screening Values for
the Wisconsin Monitoring Sites
Pollutant
#of
Failures
#of
Measured
Detections
% of Screens
Failed
% of Total
Failures
Cumulative
%
Contribution
Madison, Wisconsin - MAWI
Acetaldehyde
Benzene
Carbon Tetrachloride
1,3 -Butadiene
Formaldehyde
Hexachloro- 1 ,3 -butadiene
Tetrachloroethylene
Total
8
8
8
6
6
4
2
42
8
8
8
7
8
4
4
47
100.00
100.00
100.00
85.71
75.00
100.00
50.00
89.36
19.05
19.05
19.05
14.29
14.29
9.52
4.76
19.05
38.10
57.14
71.43
85.71
95.24
100.00
Mayville, Wisconsin - MVWI
Hexavalent Chromium
0
37
0.00
0.00
0.00
• None of the hexavalent chromium measured detections at MVWI failed the screen.
However, in order to facilitate analysis, hexavalent chromium was considered
MVWFs pollutant of interest.
31.2 Concentration Averages
Three types of concentration averages were calculated for the pollutants of interest: daily,
seasonal, and annual. The daily average of a particular pollutant is simply the average
concentration of all measured detections. If there were at least seven measured detections within
each season, then a seasonal average was calculated. The seasonal average includes 1/2 MDLs
substituted for all non-detects. A seasonal average was not calculated for pollutants with less
than seven measured detections in a respective season. Finally, the annual average is the
average concentration of all measured detections and 1/2 MDLs substituted for non-detects. The
resulting daily average concentrations may therefore be inherently higher than the annual
average concentrations where 1/2 MDLs replacing non-detects are incorporated into the average.
Annual averages were calculated for monitoring sites where sampling began no later than
February and ended no earlier than November. Daily and seasonal average concentrations are
presented in Table 31-3. Annual averages are presented and discussed in further detail in later
sections.
31-8
-------
Table 31-3. Daily and Seasonal Averages for the Pollutants of Interest for the Wisconsin Monitoring Sites
Pollutant
#of
Measured
Detections
#of
Samples
Daily
Avg
(Hg/m3)
Conf.
Int.
Winter
Avg
(Ug/m3)
Conf.
Int.
Spring
Avg
(Ug/m3)
Conf.
Int.
Summer
Avg
(Ug/m3)
Conf.
Int.
Autumn
Avg
(Ug/m3)
Conf.
Int.
Madison, Wisconsin (MAWI)
Acetaldehyde
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Formaldehyde
Hexachloro- 1 ,3 -butadiene
8
8
7
8
8
4
8
8
8
8
8
8
1.17
0.79
0.08
0.57
1.26
0.19
0.23
0.18
0.03
0.05
0.30
0.05
1.17
0.79
0.07
0.57
1.26
NR
0.23
0.18
0.03
0.05
0.30
NR
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Mayville, Wisconsin (MVWI)
Hexavalent Chromium
37
60
2.1E-05
3.6E-06
1.1E-05
3.7E-06
1.6E-05
4.3E-06
2.0E-05
7.4E-06
1.5E-05
6.0E-06
NA = Not available due to short sampling duration.
-------
The following observations are shown in Table 31-3:
• Acetaldehyde, benzene, formaldehyde, and carbon tetrachloride were detected in
every sample collected at MAWI, while hexachloro-1,3-butadiene was detected in
only half of the samples collected.
• Among the daily averages for MAWI, formaldehyde had the highest concentration by
mass (1.26 ± 0.30 |ig/m3), followed closely by acetaldehyde (1.17 ± 0.23 |ig/m3).
• Seasonal averages of the pollutants of interest for MAWI could only be calculated for
winter.
• The daily average concentration of hexavalent chromium for MVWI was 0.021 ±
0.004 |ig/m3.
• Seasonal hexavalent chromium concentrations for the MVWI site did not vary much
statistically.
31.3 Non-Chronic Risk Evaluation
Non-chronic risk for the concentration data for MAWI and MVWI was evaluated using
ATSDR short-term (acute) and intermediate MRL and California EPA acute REL factors. Acute
risk is defined as exposures from 1 to 14 days while intermediate risk is defined as exposures
from 15 to 364 days. It is useful to compare the preprocessed daily measurements to the short-
term MRL and REL factors, as well as compare seasonal averages to the intermediate MRL.
None of the pollutants measured at either Wisconsin site exceeded the acute or intermediate risk
values.
31.4 Meteorological and Concentration Analysis
The following sub-sections describe and discuss the results of the following
meteorological analyses: Pearson correlation coefficients between meteorological parameters
(such as temperature) and concentrations of the pollutants of interest; sample-year composite
back trajectories; and sample-year wind roses.
31-10
-------
31.4.1 Pearson Correlation Analysis
Table 31-4 presents the summary of Pearson correlation coefficients for each of the
pollutants of interest and select meteorological parameters for the MAWI and MVWI monitoring
sites. (Please refer to Section 3.1.6 for more information on Pearson correlations.)
The following observations are gathered from Table 31-4:
• While strong correlations were calculated for several pollutant-meteorological
combinations for MAWI, the low number of measured detections warrants caution in
interpretation as a low number of measured detections can skew the correlations.
• Nearly all the pollutants (except carbon tetrachloride) exhibited positive correlations
with temperature and negative correlations with scalar wind speed. This indicates
that these variables may play an important role in the concentrations of the pollutants
of interest for MAWI.
• Hexavalent chromium exhibited strong positive correlations with dew point and wet
bulb temperatures for MVWI. This indicates that as moisture content increases,
concentrations of this pollutant also increase.
31.4.2 Composite Back Trajectory Analysis
Figure 31-5 and 31-6 are a composite back trajectory maps for the MAWI and MVWI
monitoring sites for the days on which sampling occurred. Each line represents the 24-hour
trajectory along which a parcel of air traveled toward the monitoring site on a sampling day.
Each concentric circle around the sites represents 100 miles.
The following observations can be made from Figure 31-5:
• Back trajectories originated from a variety of directions at MAWI, although no
trajectories originated to the east and southeast of the site.
• The 24-hour airshed domain was somewhat large at MAWI, with trajectories
originating as far away as Ontario, Canada, (> 600 miles).
• The composite trajectory map for MAWI might look much different with a full year's
worth of sampling days.
31-11
-------
Table 31-4. Pollutants of Interest Concentration Correlations with Selected Meteorological Parameters for the Wisconsin
Monitoring Sites
Pollutant
#of
Measured
Detections
Maximum
Temperature
Average
Temperature
Dew Point
Temperature
Wet Bulb
Temperature
Relative
Humidity
Sea Level
Pressure
Scalar
Wind
Speed
Madison, WI - MAWI
1,3 -Butadiene
Acetaldehyde
Benzene
Carbon Tetrachloride
Formaldehyde
Hexachloro- 1 , 3 -butadiene
7
8
8
8
8
4
0.39
0.34
0.57
-0.42
0.13
0.85
0.15
0.06
0.35
-0.27
-0.14
0.79
-0.05
-0.11
0.11
-0.38
-0.42
0.73
0.05
-0.02
0.24
-0.33
-0.27
0.76
-0.32
-0.30
-0.31
-0.49
-0.75
0.54
-0.10
-0.02
-0.19
0.61
0.24
-0.69
-0.80
-0.85
-0.69
0.38
-0.61
-0.88
Mayville, Wisconsin - MVWI
Hexavalent Chromium
37
0.48
0.48
0.53
0.51
0.04
NA
0.04
NA = Sea level pressure was not recorded at the West Bend Airport.
-------
Figure 31-5. Composite Back Trajectory Map for MAWI
-------
Figure 31-6. Composite Back Trajectory Map for MVWI
-------
The following observations can be made from Figure 31-6:
• The composite back trajectory map for MVWI looks much different than the MAWI
back trajectory map.
• Back trajectories originated from a variety of directions at MVWI.
• The 24-hour airshed domain was large, with the longest trajectories originating nearly
800 miles away in Manitoba, Canada. However, nearly 85 percent of trajectories
originated within 500 miles of MVWI.
31.4.3 Wind Rose Analysis
Hourly wind data from the Traux Field Airport and the West Bend Municipal Airport
were uploaded into a wind rose software program, WRPLOT (Lakes, 2006). WRPLOT produces
a graphical wind rose from the wind data. A wind rose shows the frequency of wind directions
about a 16-point compass, and uses different shading to represent wind speeds. Figures 31-7 and
31-8 are the wind roses for the MAWI and MVWI monitoring sites on days that sampling
occurred.
Observations from Figure 31-7 for MAWI include:
• Hourly winds near MAWI were predominantly out of the northwest (23 percent of
observations) and north-northwest (17 percent) on sampling days.
• Calm winds (<2 knots) were recorded for 8 percent of the observations.
• Wind speeds frequently ranged from 7 to 11 knots on day that samples were
collected.
Observations from Figure 31-7 for MVWI include:
• Calm winds were observed for 25 percent of the observations taken near MVWI.
• For wind speeds greater than 2 knots, hourly winds near MVWI were predominately
from the west (11 percent) and the wind speed ranged from 7 to 11 knots.
31-15
-------
Figure 31-7. Wind Rose for MAWI Sampling Days
25%
SOUTH ,---
WIND SPEED
(Knots)
| | >=22
• 17 - 21
I I 11 - 17
• 7- 11
I I A- 7
• 2- 4
Calms: 8.38%
-------
Figure 31-8. Wind Rose for MVWI Sampling Days
SOUTH ,--
WIND SPEED
(Knots)
| | >=22
I I 17 - 21
^| 11 - 17
• 7- 11
I I 4- 7
• 2- 4
Calms: 25.49%
-------
31.5 Spatial Characteristics Analysis
The following sub-sections describe and discuss the results of the following spatial
analyses: population, vehicle ownership, and traffic data comparisons; and BTEX analysis. A
mobile tracer analysis could not be performed as this site did not sample for SNMOC.
31.5.1 Population, Vehicle Ownership, and Traffic Data Comparison
County-level vehicle registration and population in Dane County, WI were obtained from
the Wisconsin Department of Transportation and the U.S. Census Bureau, and are summarized in
Table 31-5. Table 31-5 also includes a vehicle registration to county population ratio (vehicles
per person). In addition, the population within 10 miles of each site is presented. An estimation
of 10-mile vehicle registration was computed using the 10-mile population surrounding the
monitor and the vehicle registration ratio. Finally, Table 31-5 contains the average daily traffic
information, which represents the average number of vehicles passing the monitoring sites on the
nearest roadway to each site on a daily basis.
Observations gleaned from Table 31-5 include:
• The population and vehicle ownership near MAWI is significantly higher than near
MVWI.
• Compared to other UATMP sites, the MAWI site's county and 10-mile population
and vehicle registration count falls in the middle of the range. The average daily
traffic count also falls in the middle of the range compared to other UATMP sites.
The MAWI monitoring site is considered a residential but urban-city center area.
• The MVWI site's county and 10-mile population and vehicle registration fall in the
lower third compared to other UATMP sites. However, MVWI's vehicle
registration-to-population ratio was the ninth highest of all UATMP sites.
31.5.2 BTEX Analysis
A roadside study conducted to measure emissions from motor vehicles determined that
the concentration ratios of the BTEX compounds were relatively consistent from urban area-to-
urban area (for more information on this study, refer to Section 3.2.1.4). Table 3-12 and Figure
3-4 depict the average concentration ratios of the roadside study and compares them to the
concentration ratios at each of the monitoring sites in an effort to characterize the impact of on-
31-18
-------
Table 31-5. Motor Vehicle Information for the Wisconsin Monitoring Sites
Site
MAWI
MVWI
2006 Estimated
County
Population
463,826
88,983
Number of
Vehicles
Registered
425,763
95,112
Vehicles per Person
(Registration:
Population)
0.92
1.07
Population
Within 10
Miles
364,645
24,688
Estimated 10
Mile Vehicle
Ownership
334,721
26,388
Traffic Data
(Daily Average)
23,750
5,990
-------
road, or motor vehicle, emissions. MVWI is not included in this analysis as this site did not
sample VOC.
The BTEX figure and table show the following:
• For the MAWI site, the xylenes-ethylbenzene ratio (3.42 ± 0.37) was lower than the
benzene-ethylbenzene ratio (5.83 ± 0.89), which is the reverse of the roadside study
(4.55 and 2.85, respectively).
• The toluene-ethylbenzene ratio (5.95 ± 0.65) was very similar to that of the roadside
study (5.85).
• The benzene-ethylbenzene and toluene-ethylbenzene ratios are very similar for
MAWI.
31.6 Trends Analysis
For sites that participated in the UATMP prior to 2005 and are still participating in the
2006 program year (i.e., minimum 3 consecutive years), a site-specific trends analysis was
conducted. Details on how this analysis was conducted can be found in Section 3.3.4. The
MAWI site has participated since 2004. Figure 31-9 presents the trends analysis results for
formaldehyde, benzene, and 1,3-butadiene for MAWI.
The following observations can be made from Figure 31-9:
• Benzene and 1,3-butadiene decreased significantly from 2004 to 2005.
Concentrations of these pollutants did not change significantly in 2006.
• Formaldehyde, which doubled between 2004 and 2005, appears to have returned to
approximately the 2004 level.
31.7 Chronic Risk Analysis
A chronic risk analysis was completed for the pollutants that failed at least one screen at
the Wisconsin sites and where the annual average concentrations could be calculated (refer to
Section 3.3.5 regarding the definition of an annual average). Annual averages, theoretical cancer
and noncancer risk, cancer UREs and/or noncancer RfCs are presented in Table 31-6.
Additionally, the pollutants of interest are bolded. Finally, data from EPA's 1999 NATA for the
pollutants that failed at least one screen at MAWI and MVWI were retrieved and are presented in
31-20
-------
Figure 31-9. Comparison of Yearly Averages for the MAWI Monitoring Site
to
^.J
0
Q.
Q.
_ 1 R
C I-3
g
+j
4-*
c
0)
o
o
o
0) 1
TO
(1)
0.5
n
1
D
I
1
2004
1,3-Butadiene
T
1
2005
Year
• Benzene
r^
|
2006
D Formaldehyde
-------
Table 31-6. Chronic Risk Summary for the Monitoring Sites in Wisconsin
Pollutant
Cancer
URE
Oig/m3)
Noncancer
RfC
Oig/m3)
1999 NATA
Modeled
Concentration
(Ug/m3)
Cancer Risk
(in-a-
million)
Noncancer
Risk (HQ)
2006 UATMP
Annual
Average
(jig/m3)
Cancer
Risk (in-a-
million)
Noncancer
Risk (HQ)
Madison, Wisconsin (MAWI) - Census Tract ID 55025002100
Acetaldehyde
Benzene
1,3-Butadiene
Carbon Tetrachloride
Formaldehyde
Hexachloro-l,3-butadiene
Tetrachloroethylene
0.0000022
0.0000078
0.00003
0.000015
5.5E-09
0.000022
0.0000059
0.009
0.03
0.002
0.04
0.0098
0.09
0.27
1.16
1.70
0.17
0.21
1.34
0.01
0.18
2.55
13.30
4.98
3.17
0.01
0.03
1.07
0.13
0.06
0.08
0.01
0.14
0.01
O.01
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Mayville, Wisconsin (MVWI) - Census Tract ID 55027961400
Hexavalent Chromium
0.012
0.0001
0.01
0.07
0.01
0.01 ±0.01
0.18
0.01
BOLD indicates a pollutant of interest
NA = annual average not available
to
to
-------
Table 31-6. The NATA data are presented for the census tract where the monitoring site is
located.
The census tract information for the Wisconsin sites is as follows:
• The MAWI monitoring site is located in census tract 55025002100, while the MVWI
monitoring site is located in census tract 55027961400.
• The population for the census tract where the MAWI monitoring site is located was
5,093, which represents about 1.2 percent of Dane County's population in 2000.
• The population for the census tract where the MVWI monitoring site is located was
4,065, which represents about 4.7 percent of Dodge County's population in 2000.
The following observations based on annual averages can be made from Table 31-6:
• MAWI ended sampling in February; therefore, no annual averages, and annual
average-based cancer and noncancer risks, could be calculated.
• Hexavalent chromium, which was the only pollutant sampled for at MVWI, had an
annual average that was less than 0.01 |ig/m3. Cancer and noncancer risk attributable
to hexavalent chromium near MVWI was low.
The following observations based on NATA can be made from Table 31-6:
• Benzene (13.30 in-a-million), 1,3-butadiene (4.98), and carbon tetrachloride (3.17)
have the highest cancer risks in the census tract where MAWI resides.
• Noncancer risk was low for the pollutants of interest for MAWI, with all HQs less
than 0.15.
• Both the NATA-modeled and annual average concentration for hexavalent chromium
for MVWI was less than 0.01 |ig/m3.
• The NATA-modeled cancer risk (0.07 in-a-million) for hexavalent chromium was
less than the annual average-based cancer risk (0.18 in-a-million, respectively) for
MVWI, although both were low.
• Both noncancer hazard quotients were less than 0.01, suggesting very little risk for
noncancer health affects due to hexavalent chromium for MVWI.
31-23
-------
31.8 Toxicity-Weighted Emissions Assessment
In addition to the chronic risk analysis discussed above, Tables 31-7 and 31-8 present a
risk-based assessment of the county-level emissions based on cancer and noncancer toxicity,
respectively. Table 31-7 presents the 10 pollutants with the highest emissions from the 2002
NEI, the 10 pollutants with the highest toxicity-weighted emissions, and the hexavalent
chromium cancer risk (in-a-million) as calculated from the annual average. Table 31-8 identifies
the 10 pollutants with the highest emissions, noncancer toxicity-weighted emissions, and the
hexavalent chromium noncancer risk (HQ) as calculated from the annual average. The pollutants
in these tables are limited to those that have cancer and noncancer risk factors, respectively. As
a result, the highest emitted pollutants in the cancer table may not be the same as the noncancer
table, although the actual value of the emissions will be. Secondly, each site sampled for
specific types of pollutants. Therefore, the cancer and noncancer risk based on each site's annual
average is limited to those pollutants for which each respective site sampled. In addition, the
highest cancer and noncancer risks based on annual averages are limited to those pollutants
failing at least one screen.
The following observations can be made from Table 31-7:
• Benzene was the highest emitted pollutant (by mass) with a cancer risk factor and had
the highest cancer toxicity-weighted emissions for both Dane and Dodge Counties
(MAWI and MVWI, respectively).
• Formaldehyde had the second highest emissions in both Dane and Dodge Counties
(MAWI and MVWI, respectively), but this pollutant did not appear on the list of
highest cancer toxicity-weighted emissions, indicating that this pollutant has a
relatively low cancer toxicity.
• Hexavalent chromium was the only pollutant with a cancer risk based on an annual
average for MVWI. This pollutant was not one of the pollutants with the highest
cancer toxicity-weighted emissions in Dodge County (MVWI), although it ranked
ninth highest in Dane County (MAWI).
The following observations can be made from Table 31-8:
• Toluene and xylenes were the highest emitted pollutants with noncancer risk factors
in both Dane and Dodge Counties (MAWI and MVWI, respectively), but only
xylenes ranked in the top 10 based on toxicity-weighted emissions.
31-24
-------
Table 31-7. Top 10 Emissions, Toxicity-Weighted Emissions, and Cancer Risks for Pollutants with Cancer UREs
for the Wisconsin Monitoring Sites
Top 10 Total Emissions for Pollutants with
Cancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Cancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Cancer
Toxicity
Weight
Top 10 Cancer Risks Based on Annual
Average Concentration
(Site-Specific)
Cancer Risk
(in-a-
Pollutant million)
Madison, Wisconsin (MAWI) - Dane County
Benzene
Formaldehyde
Tetrachloroethylene
Dichloromethane
Acetaldehyde
1,3 -Butadiene
1 , 3 -Dichloropropene
Naphthalene
£>-Dichlorobenzene
Trichloroethylene
539.91
141.58
97.09
90.42
52.57
41.06
32.06
22.90
16.61
13.61
Benzene
1,3 -Butadiene
Lead
Poly cyclic Organic Matter as non-15 PAH
Naphthalene
Arsenic
Tetrachloroethylene
Poly cyclic Organic Matter as 15-PAH
Hexavalent Chromium
Polycyclic Organic Matter as 7-PAH
4.21E-03
1.23E-03
9.93E-04
8.80E-04
7.78E-04
6.81E-04
5.73E-04
3.42E-04
2.72E-04
2.17E-04
Mayville, Wisconsin (MVWI) - Dodge County
Benzene
Formaldehyde
Dichloromethane
Tetrachloroethylene
Acetaldehyde
1,3 -Butadiene
1 ,3 -Dichloropropene
Trichloroethylene
Naphthalene
/>-Dichlorobenzene
166.79
34.69
14.99
14.87
13.71
8.05
6.31
5.12
4.85
3.28
Benzene
Lead
Polycyclic Organic Matter as non-15 PAH
1,3 -Butadiene
Naphthalene
Polycyclic Organic Matter as 15-PAH
Tetrachloroethylene
Polycyclic Organic Matter as 7-PAH
£>-Dichlorobenzene
Acetaldehyde
1.30E-03
3.09E-04
3.05E-04
2.42E-04
1.65E-04
9.00E-05
8.77E-05
6.00E-05
3.61E-05
3.02E-05
Hexavalent Chromium 0.18
OJ
to
-------
Table 31-8. Top 10 Emissions, Toxicity-Weighted Emissions, and Noncancer Risks for Pollutants with Noncancer RfCs
for the Wisconsin Monitoring Sites
Top 10 Total Emissions for Pollutants with
Noncancer Risk Factors
(County-Level)
Pollutant
Emissions
(tpy)
Top 10 Noncancer Toxicity-Weighted Emissions
(County-Level)
Pollutant
Noncancer
Toxicity
Weight
Top 10 Noncancer Risks Based on
Annual Average Concentrations
(Site-Specific)
Noncancer
Risk
Pollutant (HQ)
Madison, Wisconsin (MAWI) - Dane County
Toluene
Xylenes
Benzene
Methyl Ethyl Ketone
1,1,1 -Trichloroethane
Methyl Isobutyl Ketone
Methanol
Hydrochloric Acid
Hexane
Ethylbenzene
1,234.32
843.56
539.91
410.93
347.17
232.35
224.01
201.19
170.86
167.35
Manganese
Acrolein
1,3 -Butadiene
Benzene
Formaldehyde
Hydrochloric Acid
Bromomethane
Xylenes
Naphthalene
Nickel
702,704.63
451,626.89
20,529.76
17,997.01
14,447.15
10,059.72
8,953.95
8,435.61
7,631.73
6,906.09
Mayville, Wisconsin (MVWI) - Dodge County
Toluene
Xylenes
Benzene
Methyl Ethyl Ketone
1,1,1 -Trichloroethane
Methanol
Ethylbenzene
Hexane
Formaldehyde
Glycol Ethers
332.41
173.12
166.79
61.15
52.24
37.30
36.39
36.32
34.69
22.98
Acrolein
Manganese
Benzene
1,3 -Butadiene
Formaldehyde
Bromomethane
Xylenes
Naphthalene
Acetaldehyde
Cyanide
95,406.11
5,767.56
5,559.69
4,026.54
3,539.37
1,760.75
1,731.25
1,617.45
1,523.59
1,384.47
Hexavalent Chromium O.01
OJ
to
-------
• Acrolein and manganese had the highest noncancer toxicity-weighted emissions in
Dodge County (MVWI), but manganese had higher toxicity-weighted emissions than
acrolein in Dane County (MAWI). This is unusual because acrolein has the highest
toxicity-weighted emissions for most of the UATMP counties. Yet, acrolein did not
appear in the list of highest emitted pollutants.
• Hexavalent chromium did not rank in the top 10 highest emitted pollutants with
noncancer risk factors or the 10 highest noncancer toxicity-weighted emissions in
either county, and had a very low noncancer risk, based on the annual average for
MVWI.
Wisconsin Pollutant Summary
• The pollutants of interest at MAWI were acetaldehyde, benzene, 1,3-butadiene, carbon
tetrachloride, formaldehyde, and hexachloro-1,3-butadiene. MVWI sampled only for
hexavalent chromium.
• No pollutants exceeded the short-term risk factors at these sites.
31-27
-------
32.0 Data Quality
This section discusses the data quality of the ambient air concentrations for the 2006
UATMP dataset. In accordance with the Data Quality Objectives (DQOs) presented in ERG's
EPA-approved QAPP, the following quality assessments were performed: completeness,
precision, and bias (also called accuracy). Completeness statistics were presented in Section 2.0
of this report. The goal of 85 percent completeness was met by most sites. As indicators of the
reliability and representativeness of experimental measurements, both precision and bias are
considered when interpreting ambient air monitoring data. The quality assessments presented in
this section shows that the 2006 monitoring data are of a known and high quality. All
calculations are based on sample concentrations measured above the MDL for each pollutant.
The overall precision level (the average for all sites) meets the data quality objective, which is a
15 percent coefficient of variation, and adheres to the guidelines in the NATTS TAD.
32.1 Precision
Precision refers to the agreement between independent measurements performed
according to identical protocols and procedures. Method precision, or sampling and analytical
precision, quantifies random errors associated with collecting ambient air samples and analyzing
the samples in the laboratory. Precision is evaluated by comparing concentrations measured in
duplicate or collocated samples collected from the same air parcel. A duplicate sample is a
sample collected simultaneously with a primary sample using the same sampling system (i.e.,
two separate samples through the same sampling system at the same time). This simultaneous
collection is typically achieved by teeing the line from the sampler to two canisters and doubling
the flow rate applied to achieve integration over the 24-hour collection period. Collocated
samples are samples collected simultaneously using two independent collection systems at the
same location at the same time.
Both approaches provide valuable, but different, assessments of method precision:
• Analysis of duplicate samples provides information on the potential for variability (or
precision) expected from a single collection system, but does not provide information
on the variability expected between different collection systems (inter-system
assessment).
32-1
-------
• Analysis of collocated samples provides information on the potential for variability
(or precision) expected between different collection systems, but does not provide
information on the variability expected from single collection systems (intra-system
assessment).
During 2006, duplicate and collocated samples were collected on at least 10 percent of
the scheduled sampling days, as outlined in the QAPP. Most of these samples were analyzed in
replicate. Duplicate/collocated samples were not collected for SVOC because there were no
collocated samplers and the samplers used were not equipped to collect duplicate samples.
Therefore, method precision for SVOC is not discussed in this section.
To calculate sampling and analytical precision, data analysts compare the concentrations
of the two duplicates/collocates for each compound. This report uses three parameters to
quantify random errors indicated by duplicate/collocated analyses of samples:
• Average concentration difference simply quantifies how duplicate or collocated
analytical results differ, on average, for each pollutant and each sample. When
interpreting central tendency estimates for specific pollutants sampled during the
2006 monitoring effort, participating agencies are encouraged to compare central
tendencies to the average concentration differences. If a pollutant' s average
concentration difference exceeds or nearly equals its central tendency, the analytical
method may not be capable of precisely characterizing the concentrations. Therefore,
data interpretation for these pollutants should be made with caution. Average
concentration differences are calculated by subtracting the first analytical result from
the second analytical result and averaging the difference for each pollutant.
• Relative percent difference (RPD) expresses average concentration differences
relative to the average concentrations measured during duplicate or collocated
analyses. The RPD is calculated as follows:
X
Where:
X\ is the ambient air concentration of a given pollutant measured in one sample;
Xi is the concentration of the same pollutant measured during duplicate or collocated
analysis; and
X is the arithmetic mean of X\ and Xi.
As this equation shows, duplicate analyses with low variability have lower RPDs (and
better precision), and duplicate analyses with high variability have higher RPDs (and
poorer precision).
32-2
-------
• Coefficient of Variation (CV) provides a relative measure of data dispersion
compared to the mean.
X
Where:
a is the standard deviation of the sets of duplicate or collocated results;
X is the arithmetic mean of the sets of duplicate or collocated results;
The CV is used to determine the imprecision in survey estimates introduced from
analysis. A coefficient of one percent would indicate that the analytical results could
vary slightly due to sampling error, while a variation of 50 percent means that the
results are more imprecise. The CV for two duplicate samples was calculated for
each pollutant and each site.
The following approach was employed to estimate how precisely the central laboratory
analyzed 2006 samples:
• CVs, RPDs, and concentration differences were calculated for every duplicate or
collocated analysis performed during the program. In cases where pollutants were
not detected during duplicate analyses, non-detects were replaced with 1/2 the MDL.
• To make an overall estimate of method precision, program-average CVs, RPDs, and
absolute concentration differences were calculated for each pollutant by averaging the
values from the individual duplicate or collocated analyses. The expression "average
variability" or "median variability" for a given dataset refers to the average or median
CV.
It is important to note that EPA has recently revised the methodology for assessing
method precision in "Revisions to Ambient Air Monitoring Regulations; Final Rule," finalized
October 17, 2006 (USEPA, 2006e). The new methodology has been applied to the 2006
Monitoring Network report. The primary change includes the substitution of 1/2 MDLs for non-
detects in calculating precision statistics. In some cases, this substitution affected the calculated
RPDs and CVs by causing those values to increase.
The Alabama (ETAL, NBAL, PVAL, SIAL), Oklahoma, and Wisconsin sites, as well as
a few other sites were not included in this section because of the low number of valid duplicate
or collocated samples throughout the 2006 sampling period. Table 32-1 presents the 2006
Monitoring Program average precision for VOC, SNMOC, carbonyl compounds, hexavalent
chromium, and metals. The overall carbonyl compounds, hexavalent chromium, and metals
32-3
-------
compounds precision (the average for all sites) meets the Program DQOs, which are 15 percent
coefficient of variation. The overall VOC and SNMOC precision is slightly above the Program
DQOs. Tables 32-2 through 32-9, 32-11 through 32-14, 32-16 through 32-25, and 32-27 through
32-30 present average concentration differences, RPDs, and CVs as estimates of duplicate
sampling and analytical variability for VOC, SNMOC, carbonyls, and metal compounds,
respectively. Tables 32-10, 32-15, 32-26, and 32-31 present the average CVs per pollutant and
per site. Table 32-32 presents the average CV for hexavalent chromium per site.
Table 32-1. Average Precision by Method
Method
VOC
SNMOC
Carbonyl Compounds
Hexavalent Chromium
Metals
Average Coefficient of
Variation (%)
21.18
21.49
11.30
10.03
11.33
32.1.1 VOC Sampling and Analytical Precision
Table 32-2 presents the sampling and analytical data precision for all duplicate and
collocated VOC samples. The average concentration differences observed for duplicate and
collocated analyses of VOC range from 0.003 ppbv (dibromochloromethane and
dichlorotetrafluoroethane) to 7.57 ppbv (acetonitrile). Pollutants exceeding the 15 percent
control limit for CV and a 25 percent control limit for RPD are bolded. Thirty-one out of
60 VOC show greater variation than the target of 15 percent.
Table 32-2. VOC Sampling and Analytical Precision: 228 Duplicate and
Collocated Samples
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Number of
Observations
164
224
179
11
0
228
Average RPD
(%)
63.97
14.03
53.04
47.55
NA
16.59
Average Concentration
Difference (ppbv)
7.57
0.14
0.18
0.05
NA
0.06
Coefficient of
Variation (%)
45.24
9.92
37.51
33.62
NA
11.73
32-4
-------
Table 32-2. VOC Sampling and Analytical Precision: 228 Duplicate and
Collocated Samples (Continued)
Pollutant
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
OT-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
?raw5-l,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Acrylate
Ethyl tert-Butyl Ether
Ethylbenzene
Hexachloro- 1 , 3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tert-Butyl Ether
w-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1,1,2-Trichloroethane
Number of
Observations
0
9
0
188
190
200
228
8
137
161
228
0
0
8
0
2
2
165
228
0
5
0
5
5
219
0
0
1
228
1
6
228
14
216
174
5
48
181
228
192
2
157
228
2
227
0
Average RPD
(%)
NA
85.44
NA
21.30
20.42
35.76
19.21
78.01
47.25
39.05
6.02
NA
NA
38.99
NA
137.41
NA
39.36
5.48
NA
62.31
NA
159.12
67.78
27.16
NA
NA
73.22
19.31
NA
NA
19.02
81.40
44.30
49.02
100.52
28.85
40.05
17.12
29.94
43.01
37.83
20.13
59.62
16.71
NA
Average Concentration
Difference (ppbv)
NA
0.01
NA
0.005
0.01
0.24
0.02
0.01
0.01
0.02
0.04
NA
NA
0.003
NA
0.01
0.01
0.01
0.03
NA
0.01
NA
0.08
0.01
1.06
NA
NA
0.01
0.003
0.01
NA
0.12
0.02
0.22
0.03
0.28
0.01
0.01
0.07
0.11
0.004
0.04
0.15
0.01
0.01
NA
Coefficient of
Variation (%)
NA
60.42
NA
15.06
14.44
25.29
13.59
55.16
33.41
27.61
4.26
NA
NA
27.57
NA
97.16
NA
27.83
3.88
NA
44.06
NA
112.51
47.93
19.20
NA
NA
51.78
13.65
NA
NA
13.45
57.56
31.32
34.66
71.08
20.40
28.32
12.10
21.17
30.42
26.75
14.24
42.16
11.81
NA
32-5
-------
Table 32-2. VOC Sampling and Analytical Precision: 228 Duplicate and
Collocated Samples (Continued)
Pollutant
Trichloroethylene
Trichlorofluoromethane
Trichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1 ,3 ,5-Trimethylbenzene
Vinyl chloride
w,£>-Xylene
o-Xylene
Number of
Observations
56
228
228
219
198
12
228
226
Average RPD
(%)
84.65
7.53
10.72
27.86
26.87
77.39
20.59
19.94
Average Concentration
Difference (ppbv)
0.02
0.02
0.01
0.02
0.01
0.01
0.08
0.03
Coefficient of
Variation (%)
59.86
5.33
7.58
19.70
19.00
54.72
14.56
14.10
The VOC sampling and analytical data for all collocated samples are presented in Table
32-3. The range of variability was 4.82 percent (chloromethane) to 139.98 percent (methyl
methacrylate). The median variability is 27.99 percent.
Table 32-3. VOC Sampling and Analytical Precision:
80 Collocated Samples
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
Number of
Observations
56
80
65
8
0
80
0
9
0
57
64
60
80
8
45
56
80
0
0
8
0
0
0
66
80
Average RPD
(%)
112.91
17.69
47.42
38.62
NA
26.83
NA
85.44
NA
32.41
22.75
69.83
13.58
78.01
56.15
37.52
6.81
NA
NA
38.99
NA
NA
NA
57.74
6.83
Average
Concentration
Difference (ppbv)
14.40
0.14
0.21
0.08
NA
0.08
NA
0.01
NA
0.01
0.01
0.44
0.01
0.01
0.01
0.02
0.04
NA
NA
0.003
NA
NA
NA
0.02
0.04
Coefficient of
Variation (%)
79.84
12.51
33.53
27.31
NA
18.97
NA
60.42
NA
22.92
16.09
49.38
9.60
55.16
39.71
NA
4.82
NA
NA
27.57
NA
NA
NA
40.83
4.83
32-6
-------
Table 32-3. VOC Sampling and Analytical Precision:
80 Collocated Samples (Continued)
Pollutant
1, 1-Dichloroethane
1,2-Dichloroethane
1, 1-Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Acrylate
Ethyl fer/-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl ferMSutyl Ether
w-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Vinyl chloride
w,/?-Xylene
o-Xylene
Number of
Observations
0
2
0
1
1
73
0
0
0
80
0
0
80
7
77
62
3
6
58
80
62
2
49
80
2
79
0
23
80
80
76
72
4
80
80
Average RPD
(%)
NA
93.20
NA
134.24
9.59
40.00
NA
NA
NA
19.69
NA
NA
33.01
96.14
48.91
53.72
197.96
110.00
59.73
21.47
39.58
43.01
54.94
35.05
59.62
22.89
NA
92.05
12.84
16.83
37.46
30.63
63.37
29.19
30.17
Average
Concentration
Difference (ppbv)
NA
0.01
NA
0.03
0.001
0.05
NA
NA
NA
0.003
NA
NA
0.34
0.02
0.30
0.05
0.56
0.03
0.02
0.07
0.30
0.00
0.04
0.17
0.01
0.01
NA
0.03
0.04
0.03
0.03
0.01
0.01
0.20
0.05
Coefficient of
Variation (%)
NA
65.90
NA
94.92
6.78
28.28
NA
NA
NA
13.92
NA
NA
23.34
67.98
34.58
37.98
139.98
77.78
42.24
15.18
27.99
30.42
38.85
24.78
42.16
16.19
NA
65.09
9.08
11.90
26.49
21.66
44.81
20.64
21.33
Table 32-4 presents the results from all duplicate analyses for VOC. The variability
ranges from 2.18 percent (methyl methacrylate) to 121.31 percent (c/5-l,2-dichloroethylene).
The median variability is 16.57 percent, which shows that most of the pollutants meet the
program DQO.
32-7
-------
Table 32-4. VOC Sampling and Analytical Precision:
148 Duplicate Samples
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fer/-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tert-Butyl Ether
^-Octane
Propylene
Styrene
Number of
Observations
108
144
114
o
6
0
148
0
0
0
131
126
140
148
0
92
105
148
0
0
0
0
2
2
99
148
0
3
0
4
4
146
0
0
1
148
1
6
148
7
139
112
2
42
123
148
130
Average RPD
(%)
41.39
12.35
55.64
56.48
NA
11.86
NA
NA
NA
17.26
19.53
22.65
21.81
NA
42.79
39.88
5.65
NA
NA
NA
NA
137.41
NA
27.11
4.86
NA
31.41
NA
171.56
125.97
21.23
NA
NA
73.22
19.13
NA
NA
12.56
66.67
42.17
46.85
3.08
12.62
31.11
15.11
25.49
Average
Concentration
Difference (ppbv)
4.42
0.15
0.16
0.03
NA
0.04
NA
NA
NA
0.004
0.02
0.16
0.02
NA
0.01
0.02
0.04
NA
NA
NA
NA
0.01
0.01
0.01
0.03
NA
0.01
NA
0.10
0.02
1.53
NA
NA
0.01
0.003
0.01
NA
0.01
0.01
0.18
0.02
0.01
0.01
0.01
0.08
0.02
Coefficient of
Variation (%)
29.27
8.73
39.34
39.94
NA
8.39
NA
NA
NA
12.20
13.81
16.02
15.42
NA
30.26
28.20
4.00
NA
NA
NA
NA
97.16
NA
19.17
3.44
NA
22.21
NA
121.31
89.07
15.01
NA
NA
51.78
13.53
NA
NA
8.88
47.14
29.82
33.13
2.18
8.93
22.00
10.68
18.03
32-8
-------
Table 32-4. VOC Sampling and Analytical Precision:
148 Duplicate Samples (Continued)
Pollutant
1, 1,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Vinyl chloride
m,p-Xylene
o-Xylene
Number of
Observations
0
108
148
0
148
0
33
148
148
143
126
8
148
146
Average RPD
(%)
NA
28.50
13.25
NA
13.27
NA
78.73
5.09
7.90
23.43
24.52
86.74
16.62
15.21
Average
Concentration
Difference (ppbv)
NA
0.04
0.14
NA
0.004
NA
0.01
0.01
0.01
0.01
0.01
0.01
0.03
0.01
Coefficient of
Variation (%)
NA
20.15
9.37
NA
9.38
NA
55.67
3.60
5.59
16.57
17.34
61.33
11.75
10.76
Table 32-5 through 32-9 present the VOC precision data results for all of the NATTS
sites that sampled VOC (BTUT, DEMI, GPCO, NBIL, and S4MO, respectively).
Table 32-5 presents the results from VOC duplicate analysis for BTUT. Variability
ranges from 2.76 percent (trichlorofluoromethane) to 52.77 percent (acrolein) with an average of
12.12 percent.
Table 32-5. VOC Sampling and Analytical Precision:
12 Duplicate Samples for Bountiful, UT (BTUT)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
fer/-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Number of
Observations
7
12
10
0
0
12
0
0
0
12
12
12
Average RPD
(%)
13.62
4.33
74.63
NA
NA
4.68
NA
NA
NA
11.11
12.17
8.35
Average
Concentration
Difference (ppbv)
0.20
0.05
0.28
NA
NA
0.02
NA
NA
NA
0.002
0.01
0.28
Coefficient of
Variation (%)
9.63
3.07
52.77
NA
NA
3.31
NA
NA
NA
7.86
8.61
5.91
32-9
-------
Table 32-5. VOC Sampling and Analytical Precision:
12 Duplicate Samples for Bountiful, UT (BTUT) (Continued)
Pollutant
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
OT-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fer/-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl fer/-Butyl Ether
w-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1, 1,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Number of
Observations
12
0
9
9
12
0
0
0
0
1
1
12
12
0
1
0
0
1
12
0
0
0
12
0
0
12
0
10
12
0
0
12
12
10
0
12
12
0
12
0
1
12
12
12
12
Average RPD
(%)
35.65
NA
35.00
16.67
3.92
NA
NA
NA
NA
NA
NA
22.22
4.87
NA
NA
NA
NA
NA
16.00
NA
NA
NA
11.11
NA
NA
11.89
NA
46.25
15.20
NA
NA
14.83
10.64
19.09
NA
10.37
7.29
NA
6.67
NA
NA
3.91
5.30
34.81
30.00
Average
Concentration
Difference (ppbv)
0.02
NA
0.01
0.01
0.02
NA
NA
NA
NA
0.01
0.01
0.003
0.03
NA
0.03
NA
NA
0.01
0.02
NA
NA
NA
0.002
NA
NA
0.01
NA
0.23
0.01
NA
NA
0.01
0.05
0.01
NA
0.003
0.06
NA
0.002
NA
0.01
0.01
0.01
0.04
0.01
Coefficient of
Variation (%)
25.21
NA
24.75
11.79
2.77
NA
NA
NA
NA
NA
NA
15.71
3.44
NA
NA
NA
NA
NA
11.31
NA
NA
NA
7.86
NA
NA
8.41
NA
32.70
10.75
NA
NA
10.48
7.53
13.50
NA
7.33
5.15
NA
4.71
NA
NA
2.76
3.75
24.62
21.21
32-10
-------
Table 32-5. VOC Sampling and Analytical Precision:
12 Duplicate Samples for Bountiful, UT (BTUT) (Continued)
Pollutant
Vinyl chloride
m,p-Xylene
o-Xylene
Number of
Observations
1
12
12
Average RPD
(%)
NA
11.61
11.82
Average
Concentration
Difference (ppbv)
0.01
0.04
0.02
Coefficient of
Variation (%)
NA
8.21
8.36
Table 32-6 presents the precision results from VOC collocated analysis for DEMI. These
results show a low to high level variability, ranging from 1.50 percent (dichlorodifluoromethane)
to 44.89 percent (methyl isobutyl ketone). The average CV, which is within the Program DQO,
is 11.27 percent.
Table 32-6. VOC Sampling and Analytical Precision:
10 Collocated Samples for Detroit, MI (DEMI)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
ter/-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
Number of
Observations
8
10
6
0
0
10
0
0
0
6
6
0
10
6
6
10
10
0
0
0
0
0
0
8
10
0
0
Average RPD
(%)
8.61
13.39
22.04
NA
NA
3.90
NA
NA
NA
NA
NA
NA
11.53
22.22
22.22
36.54
2.21
NA
NA
NA
NA
NA
NA
16.67
2.12
NA
NA
Average
Concentration
Difference (ppbv)
1.01
0.09
0.05
NA
NA
0.02
NA
NA
NA
NA
NA
NA
0.01
0.003
0.003
0.04
0.01
NA
NA
NA
NA
NA
NA
0.003
0.01
NA
NA
Coefficient of
Variation (%)
6.09
9.46
15.59
NA
NA
2.76
NA
NA
NA
NA
NA
NA
8.15
15.71
15.71
25.84
1.57
NA
NA
NA
NA
NA
NA
11.79
1.50
NA
NA
32-11
-------
Table 32-6. VOC Sampling and Analytical Precision:
10 Collocated Samples for Detroit, MI (DEMI) (Continued)
Pollutant
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Acrylate
Ethyl tort-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tert-Butyl Ether
w-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Vinyl chloride
w,;?-Xylene
o-Xylene
Number of
Observations
0
0
0
10
0
0
0
10
0
0
10
0
10
7
0
0
6
10
7
0
8
10
0
10
0
2
10
10
10
10
0
10
10
Average RPD
(%)
NA
NA
NA
11.08
NA
NA
NA
13.33
NA
NA
16.74
NA
24.24
63.48
NA
NA
46.15
3.72
35.32
NA
9.59
5.70
NA
8.00
NA
NA
2.95
9.79
8.57
8.00
NA
8.64
9.63
Average
Concentration
Difference (ppbv)
NA
NA
NA
0.01
NA
NA
NA
0.002
NA
NA
0.01
NA
0.08
0.02
NA
NA
0.03
0.01
0.01
NA
0.02
0.02
NA
0.002
NA
NA
0.01
0.01
0.01
0.002
NA
0.01
0.01
Coefficient of
Variation (%)
NA
NA
NA
7.83
NA
NA
NA
9.43
NA
NA
11.83
NA
17.14
44.89
NA
NA
32.64
2.63
24.98
NA
6.78
4.03
NA
5.66
NA
NA
2.09
6.92
6.06
5.66
NA
6.11
6.81
Table 32-7 presents the results from VOC duplicate analysis for GPCO. The variability
ranges from 2.18 percent (methyl methacrylate) to 53.01 percent (chloroform). The average
variability is 13.35 percent.
32-12
-------
Table 32-7. VOC Sampling and Analytical Precision:
12 Duplicate Samples for Grand Junction, CO (GPCO)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1, 1-Dichloroethane
1,2-Dichloroethane
1, 1-Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl ferMSutyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl ter/-Butyl Ether
w-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
Number of
Observations
12
12
12
0
0
12
0
0
0
10
12
12
12
0
9
7
12
0
0
0
0
0
0
8
12
0
0
0
0
0
12
0
0
0
12
0
0
12
0
10
9
2
0
12
12
12
0
Average RPD
(%)
26.01
6.14
71.03
NA
NA
6.41
NA
NA
NA
13.33
19.59
8.07
24.22
NA
16.98
74.97
6.37
NA
NA
NA
NA
NA
NA
33.33
6.22
NA
NA
NA
NA
NA
12.37
NA
NA
NA
11.11
NA
NA
6.79
NA
39.31
59.59
3.08
NA
NA
8.46
24.56
NA
Average Concentration
Difference (ppbv)
0.24
0.08
0.20
NA
NA
0.03
NA
NA
NA
0.002
0.01
0.12
0.02
NA
0.001
0.01
0.04
NA
NA
NA
NA
NA
NA
0.01
0.04
NA
NA
NA
NA
NA
0.01
NA
NA
NA
0.002
NA
NA
0.01
NA
0.12
0.02
0.01
NA
NA
0.04
0.02
NA
Coefficient of
Variation (%)
18.39
4.34
50.22
NA
NA
4.53
NA
NA
NA
9.43
13.85
5.71
17.12
NA
12.01
53.01
4.50
NA
NA
NA
NA
NA
NA
23.57
4.40
NA
NA
NA
NA
NA
8.75
NA
NA
NA
7.86
NA
NA
4.80
NA
27.79
42.14
2.18
NA
NA
5.98
17.36
NA
32-13
-------
Table 32-7. VOC Sampling and Analytical Precision:
12 Duplicate Samples for Grand Junction, CO (GPCO) (Continued)
Pollutant
retrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Vinyl chloride
m,p-Xylene
o-Xylene
Number of
Observations
12
12
0
12
0
0
12
12
12
12
0
12
12
Average RPD
(%)
19.74
7.41
NA
6.67
NA
NA
4.07
5.51
12.88
NA
NA
6.50
6.80
Average Concentration
Difference (ppbv)
0.01
0.04
NA
0.002
NA
NA
0.01
0.01
0.01
NA
NA
0.02
0.01
Coefficient of
Variation (%)
13.96
5.24
NA
4.71
NA
NA
2.88
3.90
9.11
NA
NA
4.60
4.81
Table 32-8 presents the results from VOC collocated analysis for NBIL. The variability,
in terms of CV, ranges from 2.66 percent (carbon tetrachloride) to 80.90 percent
(p-dichlorobenzene). The average and median CV are 38.15 percent and 35.73 percent,
respectively. The average and the median CV show that the variability of most compounds at
the NBIL site are mid- to high-level.
Table 32-8. VOC Sampling and Analytical Precision:
12 Collocated Samples for Northbrook, IL (NBIL)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
fer/-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Number of
Observations
6
12
8
1
0
12
0
8
0
10
8
8
12
0
8
11
Average RPD
(%)
84.93
16.55
81.36
32.93
NA
48.73
NA
33.33
NA
26.67
48.89
46.54
3.76
NA
87.49
69.02
Average
Concentration
Difference (ppbv)
0.24
0.07
0.17
0.01
NA
0.07
NA
0.01
NA
0.004
0.01
0.02
0.01
NA
0.02
0.06
Coefficient of
Variation (%)
60.06
11.70
57.53
23.29
NA
34.46
NA
23.57
NA
18.86
34.57
32.91
2.66
NA
61.86
48.80
32-14
-------
Table 32-8. VOC Sampling and Analytical Precision:
12 Collocated Samples for Northbrook, IL (NBIL) (Continued)
Pollutant
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
£>-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl tort-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl ter/-Butyl Ether
w-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1, 1,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Vinyl chloride
w,p-Xylene
o-Xylene
Number of
Observations
12
0
0
7
0
0
0
7
12
0
0
0
0
1
10
0
0
0
12
0
0
12
0
10
6
0
0
7
12
6
1
9
12
0
12
0
7
12
12
9
8
0
12
12
Average RPD
(%)
8.65
NA
NA
15.60
NA
NA
NA
114.41
11.04
NA
NA
NA
NA
9.59
72.43
NA
NA
NA
33.33
NA
NA
47.41
NA
101.87
77.29
NA
NA
95.28
46.02
52.17
43.01
105.70
68.86
NA
61.21
NA
114.35
32.91
6.11
72.60
64.80
NA
52.94
54.57
Average
Concentration
Difference (ppbv)
0.04
NA
NA
0.001
NA
NA
NA
0.03
0.06
NA
NA
NA
NA
0.001
0.11
NA
NA
NA
0.01
NA
NA
0.02
NA
0.67
0.06
NA
NA
0.01
0.08
0.01
0.004
0.04
0.13
NA
0.03
NA
0.05
0.14
0.01
0.02
0.01
NA
0.06
0.03
Coefficient of
Variation (%)
6.12
NA
NA
11.03
NA
NA
NA
80.90
7.81
NA
NA
NA
NA
6.78
51.21
NA
NA
NA
23.57
NA
NA
33.52
NA
72.03
54.65
NA
NA
67.37
32.54
36.89
30.42
74.74
48.69
NA
43.28
NA
80.85
23.27
4.32
51.33
45.82
NA
37.43
38.59
32-15
-------
Table 32-9 presents the results from VOC duplicate analysis for S4MO. The variability
ranges from 2.04 percent (chloromethane) to 61.33 percent (vinyl chloride), with a median CV of
15.13 percent.
Table 32-9. VOC Sampling and Analytical Precision:
10 Duplicate Samples for St. Louis, MO (S4MO)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
fer/-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
£>-Dichlorobenzene
Dichlorodifluoromethane
1, 1-Dichloroethane
1,2-Dichloroethane
1, 1-Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Acrylate
Ethyl tort-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Number of
Observations
6
10
8
1
0
10
0
0
0
10
10
6
10
0
7
8
10
0
0
0
0
0
0
8
10
0
0
0
0
0
10
0
0
0
10
0
0
10
0
Average RPD
(%)
52.21
3.90
51.17
54.16
NA
7.51
NA
NA
NA
13.33
4.44
25.46
40.15
NA
74.86
NA
2.88
NA
NA
NA
NA
NA
NA
NA
4.25
NA
NA
NA
NA
NA
11.79
NA
NA
NA
26.67
NA
NA
23.58
NA
Average
Concentration
Difference (ppbv)
1.52
0.02
0.14
0.02
NA
0.02
NA
NA
NA
0.002
0.002
0.02
0.02
NA
0.01
NA
0.02
NA
NA
NA
NA
NA
NA
NA
0.02
NA
NA
NA
NA
NA
0.02
NA
NA
NA
0.004
NA
NA
0.02
NA
Coefficient of
Variation (%)
36.92
2.76
36.19
38.30
NA
5.31
NA
NA
NA
9.43
3.14
18.00
28.39
NA
52.93
NA
2.04
NA
NA
NA
NA
NA
NA
NA
3.01
NA
NA
NA
NA
NA
8.34
NA
NA
NA
18.86
NA
NA
16.67
NA
32-16
-------
Table 32-9. VOC Sampling and Analytical Precision:
10 Duplicate Samples for St. Louis, MO (S4MO) (Continued)
Pollutant
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl ferMSutyl Ether
w-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
Trichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1 ,3 ,5-Trimethylbenzene
Vinyl chloride
m,p-Xylene
o-Xylene
Number of
Observations
10
9
0
0
10
10
10
0
8
10
0
10
0
6
10
10
10
9
1
10
10
Average RPD
(%)
34.51
56.94
NA
NA
13.33
11.28
33.70
NA
10.00
6.53
NA
NA
NA
NA
11.72
3.81
39.52
45.95
86.74
19.23
21.40
Average
Concentration
Difference (ppbv)
0.21
0.02
NA
NA
0.002
0.03
0.02
NA
0.002
0.03
NA
NA
NA
NA
0.04
0.004
0.01
0.01
0.01
0.02
0.01
Coefficient of
Variation (%)
24.40
40.26
NA
NA
9.43
7.98
23.83
NA
7.07
4.62
NA
NA
NA
NA
8.29
2.69
27.95
32.49
61.33
13.60
15.13
Table 32-10 presents the average CV per pollutant, per pollutant per site, per site, and the
overall average CV. The results from duplicate and collocated samples show low- to high- level
variability among sites, ranging from an average CV of 11.27 percent at DEMI to 39.00 percent
at WETX. The average pollutant-specific CV ranged from 3.88 percent
(dichlorodifluoromethane) to 112.51 percent (cw-l,2-dichloroethylene). The overall average is
21.18 percent. This is higher than the Program DQO of 15 percent overall CV per site.
32.1.2 SNMOC Sampling and Analytical Precision
The SNMOC sampling and analytical precision for duplicate and collocated samples is
presented in Table 32-11. The average concentration differences observed for duplicate and
collocated sample analysis range from 0.02 ppbC (1,3-butadiene) to 48.09 ppbC (TNMOC). The
variation ranges from 6.31 percent (propane) to 114.98 percent (c/s-2-hexene).
32-17
-------
Table 32-10. VOC Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Samples by Site
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1, 1-Dichloroethane
Average
45.24
9.92
37.51
33.62
NA
11.73
NA
60.42
NA
15.06
14.44
25.29
13.59
55.16
33.41
27.61
4.26
NA
NA
27.57
NA
97.16
NA
27.83
3.88
NA
Barceloneta, PR
(BAPR)
13.11
13.40
43.86
78.36
NA
10.79
NA
NA
NA
9.43
18.21
18.59
4.80
NA
34.96
4.99
2.85
NA
NA
NA
NA
NA
NA
10.03
2.64
NA
Bountiful, UT
(BTUT)
9.63
3.07
52.77
NA
NA
3.31
NA
NA
NA
7.86
8.61
5.91
25.21
NA
24.75
11.79
2.77
NA
NA
NA
NA
NA
NA
15.71
3.44
NA
Camden, NJ
(CANJ)
24.70
6.62
33.61
NA
NA
9.46
NA
NA
NA
1.27
6.73
11.76
7.25
NA
14.14
9.43
6.46
NA
NA
NA
NA
NA
NA
NA
4.60
NA
Chester, NJ
(CHNJ)
41.67
8.64
30.57
NA
NA
10.08
NA
NA
NA
NAN
33.70
24.63
26.73
NA
30.02
11.79
2.81
NA
NA
NA
NA
NA
NA
39.56
1.88
NA
0
!/5
tfff
« £
1 ^
uB
24.87
4.40
17.24
3.16
NA
7.26
NA
NA
NA
15.92
7.20
19.97
10.25
NA
31.43
44.07
5.55
NA
NA
NA
NA
NA
NA
23.57
5.52
NA
Detroit, MI
(DEMI)
6.09
9.46
15.59
NA
NA
2.76
NA
NA
NA
NA
NA
NA
8.15
15.71
15.71
25.84
1.57
NA
NA
NA
NA
NA
NA
11.79
1.50
NA
Elizabeth, NJ
(ELNJ)
39.76
9.52
41.35
NA
NA
7.17
NA
NA
NA
NA
6.10
11.43
20.42
NA
21.43
NA
4.42
NA
NA
NA
NA
NA
NA
1.84
3.97
NA
Grand Junction, CO
(GPCO)
18.39
4.34
50.22
NA
NA
4.53
NA
NA
NA
9.43
13.85
5.71
17.12
NA
12.01
53.01
4.50
NA
NA
NA
NA
NA
NA
23.57
4.40
NA
Gulfport, MS
(GPMS)
16.61
7.92
47.42
NA
NA
6.89
NA
NA
NA
29.56
6.60
19.17
3.64
NA
33.94
33.04
4.22
NA
NA
NA
NA
NA
NA
26.71
4.10
NA
Nashville, TN
(LDTN)
84.23
15.72
16.57
NA
NA
7.44
NA
NA
NA
44.33
5.05
37.59
23.23
NA
35.36
5.51
7.69
NA
NA
NA
NA
NA
NA
38.77
7.96
NA
-------
Table 32-10. VOC Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Samples by Site (Continued)
Pollutant
1,2-Dichloroethane
1, 1-Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Acrylate
Ethyl tort-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tort-Butyl Ether
rc-Octane
Propylene
Styrene
1, 1,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
Trichloroethylene
Average
44.06
NA
112.51
47.93
19.20
NA
NA
51.78
13.65
NA
NA
13.45
57.56
31.32
34.66
71.08
20.40
28.32
12.10
21.17
30.42
26.75
14.24
42.16
11.81
NA
59.86
Barceloneta, PR
(BAPR)
NA
NA
NA
NA
9.45
NA
NA
NA
7.86
NA
NA
10.04
NA
49.16
22.65
NA
3.14
50.15
21.20
18.56
NA
21.66
10.69
NA
12.57
NA
NA
Bountiful, UT
(BTUT)
NA
NA
NA
NA
11.31
NA
NA
NA
7.86
NA
NA
8.41
NA
32.70
10.75
NA
NA
10.48
7.53
13.50
NA
7.33
5.15
NA
4.71
NA
NA
Camden, NJ
(CANJ)
NA
NA
NA
NA
0.75
NA
NA
NA
NA
NA
NA
2.77
NA
22.39
21.89
NA
4.43
NA
3.77
15.71
NA
4.29
7.52
NA
NA
NA
NA
Chester, NJ
(CHNJ)
NA
NA
NA
NA
21.78
NA
NA
NA
6.73
NA
NA
15.31
47.14
30.33
56.57
NA
13.30
30.63
11.44
10.04
NA
NA
8.93
NA
12.12
NA
NA
0
!/5
tfff
« £
1 ^
uB
NA
NA
NA
NA
7.39
NA
NA
NA
6.73
NA
NA
5.69
NA
31.38
21.25
NA
NA
4.13
10.47
5.63
NA
NA
4.31
NA
6.73
NA
NA
Detroit, MI
(DEMI)
NA
NA
NA
NA
7.83
NA
NA
NA
9.43
NA
NA
11.83
NA
17.14
44.89
NA
NA
32.64
2.63
24.98
NA
6.78
4.03
NA
5.66
NA
NA
Elizabeth, NJ
(ELNJ)
NA
NA
NA
NA
7.09
NA
NA
NA
13.47
NA
NA
8.69
NA
13.61
46.81
NA
1.48
9.64
7.68
28.65
NA
2.74
5.92
NA
NA
NA
5.66
Grand Junction, CO
(GPCO)
NA
NA
NA
NA
8.75
NA
NA
NA
7.86
NA
NA
4.80
NA
27.79
42.14
2.18
NA
NA
5.98
17.36
NA
13.96
5.24
NA
4.71
NA
NA
Gulfport, MS
(GPMS)
NA
NA
NA
NA
15.15
NA
NA
NA
13.47
NA
NA
13.03
NA
28.83
42.92
NA
NA
10.97
11.82
12.51
NA
15.08
15.99
NA
8.08
NA
111.34
Nashville, TN
(LDTN)
NA
NA
NA
NA
29.21
NA
NA
NA
23.57
NA
NA
19.58
101.39
18.26
19.34
NA
NA
28.84
9.94
12.33
NA
14.44
9.69
NA
14.14
NA
NA
-------
Table 32-10. VOC Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Samples by Site (Continued)
Pollutant
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Vinyl chloride
m,p-Xylene
o-Xylene
Average
Average
5.33
7.58
19.70
19.00
54.72
14.56
14.10
21.18
£4
a.
sS
0)
O 'f^
"B £
** ^
M &
2.27
3.05
12.59
15.37
NA
10.39
10.71
17.42
H
P
**" f,A
"H p
M S
2.76
3.75
24.62
21.21
NA
8.21
8.36
12.12
^
Z
•V
§ ^_A
a z
§ ^
uB
3.82
7.63
14.50
NA
NA
9.06
6.40
10.04
_,
Z
^" f~3^
"S Z
_g M
1.03
2.80
17.09
31.20
NA
24.58
19.65
20.76
0
S.T ^A
a? p
u B
5.76
5.83
0.06
0.64
NA
2.33
20.00
11.96
S
^_2' f ^A
'S g
i H
«e
2.09
6.92
6.06
5.66
NA
6.11
6.81
11.27
i_j
Z
•N
w C1
"i Z
g hJ
w &
3.51
5.00
17.59
14.82
NA
9.44
12.27
13.15
O
U
a
.2
O
a
^
"a U
^ PM
O ^
2.88
3.90
9.11
NA
NA
4.60
4.81
73.35
C/5
JJ
-w
o ^
1-^
a ^
O ^
3.73
5.15
26.09
13.47
61.33
9.70
10.19
20.90
^
H
aj
r3 ^A
> H
£ O
z d>
10.29
10.54
33.73
NA
NA
14.37
16.65
23.86
to
K)
O
-------
Table 32-10. VOC Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Samples by Site (Continued)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon Bisulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1, 1-Dichloroethane
Average
45.24
9.92
37.51
33.62
NA
11.73
NA
60.42
NA
15.06
14.44
25.29
13.59
55.16
33.41
27.61
4.26
NA
NA
27.57
NA
97.16
NA
27.83
3.88
NA
Nashville, TN
(MSTN)
76.28
8.17
11.89
NA
NA
23.86
NA
NA
NA
NA
7.07
4.27
6.66
NA
23.57
3.93
3.02
NA
NA
NA
NA
NA
NA
31.65
2.34
NA
Northbrook, IL
(NBIL)
60.06
11.70
57.53
23.29
NA
34.46
NA
23.57
NA
18.86
34.57
32.91
2.66
NA
61.86
48.80
6.12
NA
NA
11.03
NA
NA
NA
80.90
7.81
NA
New Brunswick, NJ
(NBNJ)
98.28
12.22
22.10
NA
NA
16.05
NA
NA
NA
9.43
18.86
31.47
28.39
NA
51.78
45.16
6.60
NA
NA
NA
NA
NA
NA
15.82
3.20
NA
O
S
€N
%
'3 o
o a
J S
. TT
££
36.92
2.76
36.19
38.30
NA
5.31
NA
NA
NA
9.43
3.14
18.00
28.39
NA
52.93
NA
2.04
NA
NA
NA
NA
NA
NA
NA
3.01
NA
0
!/5
•N
5«
*c3
H|
§£
£&
37.82
12.83
59.92
NA
NA
3.15
NA
NA
NA
9.43
11.79
28.36
8.31
NA
20.01
23.57
2.85
NA
NA
NA
NA
NA
NA
NA
3.47
NA
C£
a.
•N
^£
%%
<% &
10.12
17.89
37.28
NA
NA
5.20
NA
NA
NA
23.57
20.97
9.33
11.38
NA
NA
34.05
4.08
NA
NA
NA
NA
NA
NA
15.71
1.75
NA
Schiller Park IL
(SPIL)
133.15
13.79
71.61
25.24
NA
27.43
NA
97.26
NA
11.79
18.86
85.99
11.75
NA
60.14
24.75
4.75
NA
NA
44.11
NA
NA
NA
39.56
5.33
NA
!/5
S
It
SI
8.59
9.88
38.90
NA
NA
19.87
NA
NA
NA
8.93
23.75
3.92
8.63
NA
35.72
39.32
2.82
NA
NA
NA
NA
97.16
NA
NA
2.72
NA
Austin, TX
(WETX)
119.23
16.18
28.00
33.40
NA
17.90
NA
NA
NA
16.69
14.88
86.13
5.15
94.61
41.60
50.34
5.75
NA
NA
NA
NA
NA
NA
42.30
4.03
NA
-------
Table 32-10. VOC Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Samples by Site (Continued)
Pollutant
1,2-Dichloroethane
1, 1-Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 , 3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Acrylate
Ethyl fer/-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl ferMSutyl Ether
w-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1, 1,2-Trichloroethane
rrichloroethylene
Average
44.06
NA
112.51
47.93
19.20
NA
NA
51.78
13.65
NA
NA
13.45
57.56
31.32
34.66
71.08
20.40
28.32
12.10
21.17
30.42
26.75
14.24
42.16
11.81
NA
59.86
Nashville, TN
(MSTN)
NA
NA
NA
NA
18.28
NA
NA
NA
9.43
NA
NA
11.37
NA
20.26
40.63
NA
77.78
NA
15.40
13.65
NA
10.83
37.85
NA
NA
NA
51.46
Northbrook, IL
(NBIL)
NA
NA
NA
6.78
51.21
NA
NA
NA
23.57
NA
NA
33.52
NA
72.03
54.65
NA
NA
67.37
32.54
36.89
30.42
74.74
48.69
NA
43.28
NA
80.85
New Brunswick, NJ
(NBNJ)
22.21
NA
128.16
NA
12.73
NA
NA
51.78
18.86
NA
NA
8.08
47.14
25.43
31.57
NA
NA
11.79
10.18
23.91
NA
8.80
9.21
NA
5.66
NA
61.46
O
S
22
'3 o
3§
. Tf
££
NA
NA
NA
NA
8.34
NA
NA
NA
18.86
NA
NA
16.67
NA
24.40
40.26
NA
NA
9.43
7.98
23.83
NA
7.07
4.62
NA
NA
NA
NA
0
!/5
•V
5«
"3
*e
Is
£&
NA
NA
114.46
NA
22.52
NA
NA
NA
31.43
NA
NA
4.71
NA
23.77
72.49
NA
NA
78.57
15.71
17.41
NA
79.52
23.23
NA
4.71
NA
NA
San Juan, PR
(SJPR)
NA
NA
NA
89.07
38.54
NA
NA
NA
NA
NA
NA
4.15
NA
30.05
15.34
NA
22.28
10.48
17.55
15.78
NA
40.77
2.78
NA
25.14
NA
12.86
Schiller Park IL
(SPIL)
NA
NA
NA
NA
28.08
NA
NA
NA
NA
NA
NA
20.73
NA
54.08
35.85
NA
NA
62.29
15.73
29.39
NA
86.41
32.30
NA
5.66
NA
44.53
!/5
S
11
II
NA
NA
NA
NA
31.36
NA
NA
NA
15.71
NA
NA
13.06
NA
47.83
6.01
NA
NA
15.71
7.55
31.47
NA
20.47
18.20
NA
NA
NA
87.05
Austin, TX
(WETX)
65.90
NA
94.92
NA
35.07
NA
NA
NA
3.63
NA
NA
43.00
34.57
25.72
32.55
139.98
NA
20.04
14.83
50.69
30.42
39.90
16.12
42.16
12.20
NA
83.52
-------
Table 32-10. VOC Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Samples by Site (Continued)
Pollutant
rrichlorofluoromethane
rrichlorotrifluoroethane
1,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Vinyl chloride
w,/?-Xylene
o-Xylene
Average
Average
5.33
7.58
19.70
19.00
54.72
14.56
14.10
21.18
Z
H
p— ^
if
g-p
nb
3.08
3.35
28.15
NA
NA
19.52
15.56
22.91
X
!K ^
•^ 0
2.55
37.03
29.24
31.55
28.28
37.34
32.47
39.00
to
to
-------
Table 32-11. SNMOC Sampling and Analytical Precision: 64 Duplicate and
Collocated Samples
Pollutant
Acetylene
Benzene
1,3 -Butadiene
w-Butane
c/s-2-Butene
Jraws-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
w-Decane
1-Decene
w-Diethylbenzene
p-Diethylbenzene
2,2-Dimethylbutane
2,3-Dimethylbutane
2,3-Dimethylpentane
2,4-Dimethylpentane
w-Dodecane
1-Dodecene
Ethane
Ethylbenzene
2-Ethyl-l-butene
Ethylene
OT-Ethyltoluene
o-Ethyltoluene
p-Ethyltoluene
w-Heptane
1-Heptene
w-Hexane
1-Hexene
c/s-2-Hexene
trans-2-Hexene
Isobutane
Isobutene/ 1 -Butene
Isopentane
Isoprene
Isopropylbenzene
2-Methyl- 1 -butene
2-Methyl-2-butene
3 -Methyl- 1 -butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2-Methylhexane
3-Methylhexane
Number of
Observations
64
64
27
64
51
51
60
58
20
56
0
35
29
62
59
61
60
29
13
63
64
0
60
61
50
59
62
43
64
54
1
5
64
61
61
56
30
52
50
1
63
64
59
52
53
63
Average RPD
(%)
11.31
16.95
18.11
15.58
26.22
30.35
19.92
20.44
49.09
34.01
NA
52.94
49.82
17.98
10.11
29.40
21.34
41.74
47.13
20.41
27.23
NA
25.67
22.28
20.31
30.31
27.56
48.45
22.15
36.45
162.60
39.83
11.10
35.03
19.62
21.92
30.80
19.58
37.96
76.21
32.56
18.21
26.30
24.28
41.87
45.47
Average
Concentration
Difference (ppbC)
0.25
0.24
0.02
0.70
0.05
0.06
0.13
0.72
0.22
0.16
NA
0.30
0.11
0.08
0.06
0.17
0.06
0.30
0.35
1.72
0.18
NA
0.51
0.10
0.05
0.09
0.20
0.09
0.31
0.09
2.00
0.11
0.33
0.39
2.13
0.15
0.04
0.11
0.09
0.20
0.24
0.12
0.09
0.06
0.29
0.69
Coefficient of
Variation (%)
7.99
11.99
12.81
11.02
18.54
21.46
14.08
14.45
34.71
24.05
NA
37.43
35.23
12.71
7.15
20.79
15.09
29.51
33.32
14.43
19.25
NA
18.15
15.76
14.36
21.43
19.49
34.26
15.66
25.78
114.98
28.17
7.85
24.77
13.88
15.50
21.78
13.85
26.84
53.89
23.02
13.02
18.59
17.17
29.61
32.15
32-24
-------
Table 32-11. SNMOC Sampling and Analytical Precision: 64 Duplicate and
Collocated Samples (Continued)
Pollutant
3-Methylpentane
2-Methylpentane
4-Methyl- 1 -pentene
2-Methyl- 1 -pentene
w-Nonane
1-Nonene
w-Octane
1-Octene
w-Pentane
1 -Pentene
cis-2 -Pentene
trans-2-Pentene
a-Pinene
&-Pinene
Propane
w-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
TNMOC (w/unknowns)
Toluene
w-Tridecane
1-Tridecene
1,2,3 -Trimethy Ibenzene
1 ,2, 4-Trimethy Ibenzene
1 , 3 ,5 -Trimethy Ibenzene
2,2,3 -Trimethy Ipentane
2,2,4-Trimethylpentane
2,3 , 4-Trimethy Ipentane
w-Undecane
1-Undecene
w-Xylene/^-Xylene
o-Xylene
Number of
Observations
64
62
6
11
59
42
62
28
64
59
44
57
52
6
64
48
64
0
38
64
64
64
5
0
51
63
53
38
64
58
40
18
64
62
Average RPD
(%)
17.21
29.25
18.46
44.08
28.49
50.28
25.05
47.18
23.51
34.69
34.63
20.36
42.94
54.59
8.92
35.15
21.27
NA
60.77
15.85
25.19
25.48
68.06
NA
38.66
33.91
26.99
47.66
21.11
27.38
44.04
21.20
22.75
24.93
Average
Concentration
Difference (ppbC)
0.16
0.84
0.04
0.09
0.11
0.21
0.12
0.10
4.83
0.12
0.05
0.05
0.36
0.34
0.57
0.08
0.19
NA
0.68
15.47
48.09
1.44
0.27
NA
0.11
0.37
0.07
0.14
0.14
0.09
0.25
0.05
0.36
0.19
Coefficient of
Variation (%)
12.12
20.68
13.05
31.17
20.14
35.55
17.72
33.36
16.62
24.53
24.49
14.39
30.36
38.60
6.31
24.85
15.04
NA
42.97
11.21
17.81
18.02
48.13
NA
27.34
23.98
19.08
33.70
14.48
19.36
31.14
14.99
16.09
17.63
Table 32-12 presents the sampling and analytical data precision for duplicate SNMOC
samples. The variation ranges from 2.62 (propane) to 114.98 (c/s-2-hexene), with a median CV
of 15.09 percent.
32-25
-------
Table 32-12. SNMOC Sampling and Analytical Precision:
52 Duplicate Samples
Pollutant
Acetylene
Benzene
1,3 -Butadiene
w-Butane
c/s-2-Butene
trans-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
w-Decane
1-Decene
w-Diethylbenzene
p-Diethylbenzene
2,2-Dimethylbutane
2,3-Dimethylbutane
2,3-Dimethylpentane
2,4-Dimethylpentane
w-Dodecane
1-Dodecene
Ethane
Ethylbenzene
2-Ethyl-l-butene
Ethylene
w-Ethyltoluene
o-Ethyltoluene
p-Ethyltoluene
w-Heptane
1-Heptene
w-Hexane
1-Hexene
c/s-2-Hexene
trans-2-Hexene
Isobutane
lsobutene/1 -Butene
Isopentane
Isoprene
Isopropylbenzene
2-Methyl- 1 -butene
2-Methyl-2-butene
3 -Methyl- 1 -butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2 -Methy Ihexane
3-Methylhexane
Number of
Observations
52
52
24
52
43
43
49
47
16
45
0
26
25
51
47
50
48
22
7
51
52
0
48
50
39
48
50
37
52
47
1
4
52
50
50
47
27
42
44
1
51
52
48
42
43
51
Average RPD
(%)
10.18
8.52
16.99
5.67
18.78
28.81
14.74
20.88
51.09
28.20
NA
44.28
39.38
16.50
6.50
23.90
16.24
37.28
47.24
17.70
20.17
NA
24.06
15.45
19.56
26.01
12.98
32.76
12.83
35.91
162.60
22.84
6.83
22.72
13.49
16.64
30.71
15.80
29.21
76.21
24.08
10.92
21.34
23.81
29.39
37.29
Average
Concentration
Difference (ppbC)
0.26
0.17
0.03
0.41
0.04
0.07
0.12
0.89
0.26
0.11
NA
0.18
0.09
0.09
0.04
0.13
0.05
0.33
0.41
0.69
0.15
NA
0.42
0.08
0.05
0.07
0.08
0.07
0.24
0.09
2.00
0.11
0.35
0.31
2.05
0.11
0.04
0.12
0.07
0.20
0.15
0.09
0.07
0.07
0.16
0.60
Coefficient of
Variation (%)
7.20
6.02
12.02
4.01
13.28
20.37
10.42
14.76
36.13
19.94
NA
31.31
27.85
11.67
4.60
16.90
11.48
26.36
33.41
12.52
14.26
NA
17.02
10.93
13.83
18.39
9.18
23.16
9.07
25.39
114.98
16.15
4.83
16.07
9.54
11.77
21.71
11.17
20.66
53.89
17.02
7.90
15.09
16.84
20.78
26.36
32-26
-------
Table 32-12. SNMOC Sampling and Analytical Precision:
52 Duplicate Samples (Continued)
Pollutant
3-Methylpentane
2-Methylpentane
4-Methyl- 1 -pentene
2-Methyl- 1 -pentene
w-Nonane
1-Nonene
w-Octane
1-Octene
w-Pentane
1 -Pentene
cis-2 -Pentene
trans-2-Pentene
a-Pinene
b-Pinene
Propane
w-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
TNMOC (w/unknowns)
Toluene
w-Tridecane
1-Tridecene
1 ,2,3 -Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3 ,4-Trimethylpentane
w-Undecane
1-Undecene
w-Xylene/^-Xylene
o-Xylene
Number of
Observations
52
52
6
10
48
35
51
23
52
47
38
46
43
6
52
40
52
0
35
52
52
52
4
0
44
51
44
29
52
46
31
14
52
51
Average RPD
(%)
13.25
21.07
18.46
11.44
25.82
44.69
19.55
48.55
19.47
30.47
27.01
13.13
45.30
54.59
3.70
32.56
16.64
NA
50.64
9.75
19.40
15.54
48.41
NA
30.12
29.92
25.42
44.82
17.70
19.29
39.83
19.65
16.01
19.69
Average
Concentration
Difference (ppbC)
0.13
0.39
0.04
0.05
0.09
0.23
0.10
0.10
5.83
0.12
0.04
0.04
0.41
0.34
0.40
0.07
0.15
NA
0.38
14.14
35.97
1.51
0.28
NA
0.07
0.38
0.06
0.13
0.10
0.06
0.24
0.04
0.26
0.11
Coefficient of
Variation (%)
9.31
14.90
13.05
8.09
18.26
31.60
13.82
34.33
13.77
21.54
19.10
9.28
32.03
38.60
2.62
23.02
11.76
NA
35.81
6.89
13.72
10.99
34.23
NA
21.30
21.15
17.98
31.69
11.96
13.64
28.17
13.90
11.32
13.92
Tables 32-13 and 32-14 present the SNMOC sampling and analytical precision data for
NATTS sites (BTUT and NBIL, respectively). Table 32-13 shows that the SNMOC variation for
the duplicate samples at BTUT ranges from 1.46 percent (propane) to 59.72 percent (n-
tridecane). The average CV is 14.04 percent, which is within the Program DQO. Table 32-14
shows the SNMOC precision data for the collocated samples at NBIL. All but two pollutants
(acetylene and cyclopentane) in Table 32-14 are outside the Program DQO.
32-27
-------
Table 32-13. SNMOC Sampling and Analytical Precision:
12 Duplicate Samples for Bountiful, UT (BTUT)
Pollutant
Acetylene
Benzene
1,3 -Butadiene
^-Butane
c/s-2-Butene
fraws-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
w-Decane
1-Decene
w-Diethylbenzene
p-Diethylbenzene
2,2-Dimethylbutane
2,3-Dimethylbutane
2,3-Dimethylpentane
2,4-Dimethylpentane
rc-Dodecane
1-Dodecene
Ethane
Ethylbenzene
2-Ethyl-l-butene
Ethylene
w-Ethyltoluene
o-Ethyltoluene
p-Ethyltoluene
w-Heptane
1-Heptene
w-Hexane
1-Hexene
c/s-2-Hexene
trans-2-Hexene
Isobutane
Isobutene/ 1 -Butene
Isopentane
Isoprene
Isopropylbenzene
2-Methyl- 1 -butene
2-Methyl-2-butene
3 -Methyl- 1 -butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2 -Methy Ihexane
3 -Methy Ihexane
Number of
Observations
12
12
7
12
12
12
12
12
3
12
0
6
5
12
12
12
12
5
2
12
12
0
10
12
12
12
12
11
12
12
0
0
12
12
12
11
6
12
12
0
12
12
12
12
12
12
Average RPD
(%)
4.13
5.97
10.28
2.89
13.12
26.87
5.43
5.12
10.09
11.63
NA
77.57
38.36
21.09
4.62
15.80
11.90
46.02
55.28
3.24
15.69
NA
7.71
21.46
26.85
35.47
10.47
20.15
2.95
16.09
NA
NA
2.10
6.90
13.72
13.99
18.39
20.84
18.60
NA
4.65
8.49
8.98
15.26
16.97
21.92
Average
Concentration
Difference (ppbC)
0.17
0.14
0.01
0.48
0.04
0.08
0.04
0.02
0.02
0.03
NA
0.28
0.10
0.11
0.03
0.18
0.07
0.11
0.15
0.18
0.10
NA
0.21
0.13
0.08
0.12
0.11
0.06
0.07
0.04
NA
NA
0.23
0.09
2.15
0.04
0.03
0.13
0.06
NA
0.07
0.12
0.03
0.05
0.12
0.45
Coefficient of
Variation (%)
2.92
4.22
7.27
2.04
9.28
19.00
3.84
3.62
7.14
8.23
NA
54.85
27.12
14.91
3.26
11.17
8.41
32.54
39.09
2.29
11.09
NA
5.45
15.17
18.99
25.08
7.40
14.25
2.08
11.38
NA
NA
1.49
4.88
9.70
9.89
13.00
14.73
13.15
NA
3.29
6.73
6.35
10.79
12.00
15.50
32-28
-------
Table 32-13. SNMOC Sampling and Analytical Precision:
12 Duplicate Samples for Bountiful, UT (BTUT) (Continued)
Pollutant
3-Methylpentane
2-Methylpentane
4-Methyl- 1 -pentene
2-Methyl- 1 -pentene
w-Nonane
1-Nonene
w-Octane
1-Octene
w-Pentane
1 -Pentene
cis-2 -Pentene
trans-2-Pentene
a-Pinene
b-Pinene
Propane
w-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
TNMOC (w/unknowns)
Toluene
w-Tridecane
1-Tridecene
1 ,2,3 -Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3 ,4-Trimethylpentane
w-Undecane
1-Undecene
w-Xylene/^-Xylene
o-Xylene
Number of
Observations
12
12
2
2
12
12
12
5
12
11
12
12
9
0
12
12
12
0
8
12
12
12
1
0
12
12
12
10
12
12
8
2
12
12
Average RPD
(%)
8.38
8.54
25.56
10.96
16.14
27.37
15.28
69.00
8.28
21.81
6.40
9.83
78.99
NA
2.07
31.16
7.10
NA
43.53
2.81
6.48
6.83
84.46
NA
37.96
27.39
29.45
37.70
11.97
17.43
43.97
11.20
9.87
13.35
Average
Concentration
Difference (ppbC)
0.11
0.27
0.05
0.01
0.05
0.05
0.08
0.12
0.47
0.07
0.01
0.03
0.53
NA
0.30
0.07
0.14
NA
0.17
2.57
10.00
0.37
0.52
NA
0.09
0.23
0.09
0.09
0.10
0.09
0.11
0.01
0.28
0.12
Coefficient of
Variation (%)
5.68
6.04
18.08
7.75
11.41
19.35
10.80
48.79
5.85
15.42
4.52
6.95
55.85
NA
1.46
22.03
5.02
NA
30.78
1.99
4.58
4.83
59.72
NA
26.84
19.37
20.83
26.66
6.22
12.33
31.09
7.92
6.98
9.44
Table 32-14. SNMOC Sampling and Analytical Precision:
12 Collocated Samples for Northbrook, IL (NBIL)
Pollutant
Acetylene
Benzene
1,3 -Butadiene
w-Butane
c/s-2-Butene
Number of
Observations
12
12
o
J
12
8
Average RPD
(%)
15.80
50.70
22.57
55.20
55.99
Average
Concentration
Difference (ppbC)
0.22
0.49
0.02
1.85
0.07
Coefficient of
Variation (%)
11.18
35.85
15.96
39.03
39.59
32-29
-------
Table 32-14. SNMOC Sampling and Analytical Precision:
12 Collocated Samples for Northbrook, IL (NBIL) (Continued)
Pollutant
trans-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
w-Decane
1-Decene
OT-Diethylbenzene
p-Diethylbenzene
2,2-Dimethylbutane
2,3-Dimethylbutane
2,3-Dimethylpentane
2,4-Dimethylpentane
rc-Dodecane
1-Dodecene
Ethane
Ethylbenzene
2-Ethyl-l-butene
Ethylene
w-Ethyltoluene
o-Ethyltoluene
p-Ethyltoluene
w-Heptane
1-Heptene
w-Hexane
1-Hexene
c/s-2-Hexene
trans-2-Hexene
Isobutane
lsobutene/1 -Butene
Isopentane
Isoprene
Isopropylbenzene
2-Methyl- 1 -butene
2-Methyl-2-butene
3 -Methyl- 1 -butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2 -Methy Ihexane
3 -Methy Ihexane
3-Methylpentane
2-Methylpentane
4-Methyl- 1 -pentene
2-Methyl- 1 -pentene
w-Nonane
Number of
Observations
8
11
11
4
11
0
9
4
11
12
11
12
7
6
12
12
0
12
11
11
11
12
6
12
7
0
1
12
11
11
9
o
J
10
6
0
12
12
11
10
10
12
12
10
0
1
11
Average RPD
(%)
36.54
40.61
18.68
41.08
57.26
NA
87.56
91.59
23.91
24.54
51.38
41.75
59.58
46.78
31.23
55.46
NA
32.07
49.61
23.33
47.52
85.88
111.19
59.39
38.63
NA
73.81
28.19
84.25
44.14
43.02
31.19
34.73
72.93
NA
66.50
47.37
46.12
26.13
91.82
78.18
33.05
61.96
NA
142.01
39.16
Average
Concentration
Difference (ppbC)
0.04
0.15
0.04
0.06
0.36
NA
0.78
0.21
0.07
0.14
0.34
0.11
0.18
0.19
5.82
0.31
NA
0.89
0.21
0.06
0.16
0.68
0.18
0.58
0.09
NA
0.12
0.24
0.70
2.45
0.28
0.05
0.06
0.16
NA
0.60
0.22
0.19
0.05
0.81
1.07
0.28
2.61
NA
0.19
0.21
Coefficient of
Variation (%)
25.84
28.72
13.21
29.05
40.49
NA
61.91
64.77
16.91
17.35
36.33
29.52
42.13
33.08
22.08
39.22
NA
22.68
35.08
16.50
33.60
60.72
78.62
42.00
27.32
NA
52.19
19.93
59.57
31.22
30.42
22.05
24.56
51.57
NA
47.02
33.49
32.61
18.48
64.93
55.28
23.37
43.81
NA
100.41
27.69
32-30
-------
Table 32-14. SNMOC Sampling and Analytical Precision:
12 Collocated Samples for Northbrook, IL (NBIL) (Continued)
Pollutant
1-Nonene
w-Octane
1-Octene
w-Pentane
1-Pentene
c/s-2-Pentene
trans-2-Pentene
a-Pinene
&-Pinene
Propane
w-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
TNMOC (w/unknowns)
Toluene
w-Tridecane
1-Tridecene
1 ,2,3 -Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 ,3 ,5-Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3 ,4-Trimethylpentane
w-Undecane
1-Undecene
w-Xylene/^-Xylene
o-Xylene
Number of
Observations
7
11
5
12
12
6
11
9
0
12
8
12
0
3
12
12
12
1
0
7
12
9
9
12
12
9
4
12
11
Average RPD
(%)
72.63
47.07
41.67
39.65
51.59
65.12
49.28
33.49
NA
29.81
45.52
39.82
NA
101.26
40.28
48.34
65.24
107.36
NA
72.83
49.91
33.24
59.01
34.75
59.74
60.88
25.83
49.71
45.92
Average
Concentration
Difference (ppbC)
0.16
0.18
0.06
0.86
0.12
0.09
0.08
0.18
NA
1.26
0.12
0.35
NA
1.87
20.82
96.55
1.19
0.25
NA
0.26
0.32
0.08
0.15
0.33
0.21
0.31
0.07
0.77
0.48
Coefficient of
Variation (%)
51.36
33.28
29.46
28.04
36.48
46.04
34.84
23.68
NA
21.08
32.18
28.16
NA
71.60
28.48
34.18
46.13
75.91
NA
51.50
35.29
23.50
41.72
24.57
42.24
43.05
18.27
35.15
32.47
Table 32-15 presents the average CV per pollutant, per pollutant per site, per site, and the
overall CV. The results from duplicate and collocated samples show low- to high-level
variability among sites, ranging from an average CV of 14 percent at BTUT to 37.03 percent at
NBIL, with an average of 21.49 percent. This overall average exceeds the 15 percent CV
Program DQO.
32-31
-------
Table 32-15. SNMOC Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Analyses by Site
Pollutant
Acetylene
Benzene
1,3 -Butadiene
w-Butane
c/5-2-Butene
/raws-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
w-Decane
1-Decene
OT-Diethylbenzene
p-Diethylbenzene
2,2-Dimethylbutane
2,3 -Dimethylbutane
2,3 -Dimethylpentane
2,4-Dimethylpentane
w-Dodecane
1-Dodecene
Ethane
Ethylbenzene
2-Ethyl-l-butene
Ethylene
OT-Ethyltoluene
o-Ethyltoluene
p-Ethyltoluene
w-Heptane
1-Heptene
w-Hexane
1-Hexene
c/s-2-Hexene
trans-2-Rexene
Isobutane
Isobutene/ 1 -Butene
Isopentane
Isoprene
Isopropylbenzene
2-Methyl- 1 -butene
2-Methyl-2-butene
3 -Methyl- 1 -butene
Methylcyclohexane
Average
7.99
11.99
12.81
11.02
18.54
21.46
14.08
14.45
34.71
24.05
NA
37.43
35.23
12.71
7.15
20.79
15.09
29.51
33.32
14.43
19.25
NA
18.15
15.76
14.36
21.43
19.49
34.26
15.66
25.78
114.98
28.17
7.85
24.77
13.88
15.50
21.78
13.85
26.84
53.89
23.02
Bountiful, UT
(BTUT)
2.92
4.22
7.27
2.04
9.28
19.00
3.84
3.62
7.14
8.23
NA
54.85
27.12
14.91
3.26
11.17
8.41
32.54
39.09
2.29
11.09
NA
5.45
15.17
18.99
25.08
7.40
14.25
2.08
11.38
NA
NA
1.49
4.88
9.70
9.89
13.00
14.73
13.15
NA
3.29
Custer, SD
(CUSD)
4.17
3.46
9.77
4.55
7.14
17.78
8.52
13.28
25.39
13.80
NA
18.40
33.13
3.13
6.59
17.18
5.47
27.73
50.18
19.99
22.82
NA
26.32
6.45
4.16
12.93
11.45
26.60
6.87
21.39
114.98
4.31
2.26
15.00
13.14
5.75
7.79
9.35
35.48
NA
19.95
Gulfport, MS
(GPMS)
5.47
12.42
20.88
5.56
15.55
34.15
20.70
27.34
80.85
30.50
NA
29.85
38.42
18.59
6.10
27.57
20.79
11.14
10.94
1.96
10.22
NA
7.51
12.02
20.42
16.53
6.40
28.92
9.75
34.83
NA
27.99
8.76
8.55
5.39
13.01
43.96
8.82
21.57
NA
21.40
Northbrook, IL
(NBIL)
11.18
35.85
15.96
39.03
39.59
25.84
28.72
13.21
29.05
40.49
NA
61.91
64.77
16.91
17.35
36.33
29.52
42.13
33.08
22.08
39.22
NA
22.68
35.08
16.50
33.60
60.72
78.62
42.00
27.32
NA
52.19
19.93
59.57
31.22
30.42
22.05
24.56
51.57
NA
47.02
0
-------
Table 32-15. SNMOC Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Analyses by Site (Continued)
Pollutant
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2-Methylhexane
3-Methylhexane
3-Methylpentane
2-Methylpentane
4-Methyl- 1 -pentene
2-Methyl-l-pentene
w-Nonane
1-Nonene
w-Octane
1-Octene
w-Pentane
1 -Pentene
cis-2 -Pentene
trans-2-Pentene
a-Pinene
&-Pinene
Propane
w-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
TNMOC (w/unknowns)
Toluene
w-Tridecane
1-Tridecene
1 ,2,3 -Trimethylbenzene
1,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3,4-Trimethylpentane
rc-Undecane
1-Undecene
m -Xy lene/p-Xy lene
o-Xylene
Average
Average
13.02
18.59
17.17
29.61
32.15
12.12
20.68
13.05
31.17
20.14
35.55
17.72
33.36
16.62
24.53
24.49
14.39
30.36
38.60
6.31
24.85
15.04
NA
42.97
11.21
17.81
18.02
48.13
NA
27.34
23.98
19.08
33.70
14.48
19.36
31.14
14.99
16.09
17.63
21.49
Bountiful, UT
(BTUT)
6.73
6.35
10.79
12.00
15.50
5.68
6.04
18.08
7.75
11.41
19.35
10.80
48.79
5.85
15.42
4.52
6.95
55.85
NA
1.46
22.03
5.02
NA
30.78
1.99
4.58
4.83
59.72
NA
26.84
19.37
20.83
26.66
6.22
12.33
31.09
7.92
6.98
9.44
14.00
Custer, SD
(CUSD)
12.29
16.88
12.01
14.42
15.78
9.87
23.60
13.24
7.67
10.23
28.27
5.81
27.89
12.51
25.63
22.79
7.24
22.01
2.14
4.79
7.11
11.92
NA
17.27
6.95
10.15
5.49
8.74
NA
12.59
10.53
19.97
34.16
10.58
10.13
8.14
21.16
8.11
11.42
75.55
Gulfport, MS
(GPMS)
6.87
17.99
13.96
26.02
44.20
14.09
19.99
7.84
8.84
18.29
57.55
13.76
44.52
9.65
28.34
33.83
18.50
10.32
56.63
2.82
42.21
12.61
NA
13.74
7.28
14.18
10.41
NA
NA
26.43
22.63
16.63
33.07
14.28
12.68
39.69
NAN
8.93
20.84
20.48
Northbrook, IL
(NBIL)
33.49
32.61
18.48
64.93
55.28
23.37
43.81
NA
100.41
27.69
51.36
33.28
29.46
28.04
36.48
46.04
34.84
23.68
NA
21.08
32.18
28.16
NA
71.60
28.48
34.18
46.13
75.91
NA
51.50
35.29
23.50
41.72
24.57
42.24
43.05
18.27
35.15
32.47
37.03
Q
!/5
0T
13
1%
ll
5.71
19.14
30.60
30.67
29.98
7.57
9.96
NA
NA
33.09
21.23
24.92
16.13
27.06
16.78
15.26
4.43
39.93
57.02
1.40
20.73
17.51
NA
81.45
11.35
25.96
23.24
NA
NA
19.32
32.09
14.48
32.88
16.74
19.43
33.75
12.61
21.26
13.99
20.41
32-33
-------
32.1.3 Carbonyl Compounds Sampling and Analytical Precision
Table 32-16, presents the sampling and analytical data for duplicate and collocated
carbonyl samples. The average concentration difference ranged from 0.005 ppbv for
isovaleraldehyde to 0.33 ppbv for formaldehyde.
Table 32-16. Carbonyl Sampling and Analytical Precision: 316 Duplicate and
Collocated Samples
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
316
316
313
313
300
0
315
307
133
314
302
306
Average RPD
(%)
12.41
16.08
16.29
11.95
12.67
NA
11.71
16.20
27.47
11.33
24.84
14.82
Average Concentration
Difference (ppbv)
0.12
0.10
0.01
0.01
0.01
NA
0.33
0.01
0.005
0.01
0.01
0.01
Coefficient of
Variation (%)
8.77
11.37
11.52
8.45
8.96
NA
8.28
11.46
19.43
8.01
17.56
10.48
The carbonyl sampling and analytical data for the 82 collocated samples are presented in
Table 32-17. The CV for carbonyl compounds range from 8.54 percent (isovaleraldehyde) to
20.14 percent (benzaldehyde).
Table 32-17. Carbonyl Sampling and Analytical Precision: 82 Collocated Samples
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Number of
Observations
82
82
79
79
74
0
Average RPD
(%)
22.27
25.15
28.49
19.27
19.56
NA
Average Concentration
Difference (ppbv)
0.15
0.15
0.01
0.01
0.01
NA
Coefficient of
Variation (%)
15.75
17.79
20.14
13.62
13.83
NA
32-34
-------
Table 32-17. Carbonyl Sampling and Analytical Precision: 82 Collocated Samples
(Continued)
Pollutant
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
82
79
33
80
78
78
Average RPD
(%)
23.36
21.73
12.07
18.40
24.82
17.74
Average Concentration
Difference (ppbv)
0.40
0.01
0.01
0.01
0.01
0.01
Coefficient of
Variation (%)
16.52
15.37
8.54
13.01
17.55
12.55
Table 32-18 presents results from carbonyl duplicate sample analysis. The data show a
low- to mid-level variability, ranging from 5.81 percent (formaldehyde) to 21.85 percent
(isovaleraldehyde), with an average of 10.12 percent.
Table 32-18. Carbonyl Sampling and Analytical Precision: 234 Duplicate Samples
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
234
234
234
234
226
0
233
228
100
234
224
228
Average RPD
(%)
9.45
13.35
12.63
9.76
10.60
NA
8.21
14.54
30.90
9.21
24.84
13.94
Average Concentration
Difference (ppbv)
0.11
0.09
0.01
0.01
0.01
NA
0.31
0.01
0.004
0.01
0.01
0.01
Coefficient of
Variation (%)
6.68
9.45
8.93
6.90
7.50
NA
5.81
10.28
21.85
6.51
17.57
9.86
Tables 32-19 through 32-25 present results from carbonyl precision data for the NATTS
sites (BTUT, DEMI, GPCO, NBIL, S4MO, SKFL, and SYFL, respectively). Table 32-19 shows
that the carbonyl compound variation for the duplicate samples at BTUT ranges from 2.35
percent (acetaldehyde) to 43.52 percent (tolualdehydes), with an average of 12.69 percent.
32-35
-------
Table 32-19. Carbonyl Sampling and Analytical Precision: 12 Duplicate Samples for
Bountiful, UT (BTUT)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
12
12
12
12
10
0
12
12
7
12
11
12
Average RPD
(%)
3.33
9.21
12.56
5.59
11.23
NA
5.23
19.44
54.56
3.74
61.55
10.97
Average Concentration
Difference (ppbv)
0.05
0.13
0.004
0.01
0.005
NA
0.14
0.01
0.01
0.005
0.03
0.01
Coefficient of
Variation (%)
2.35
6.51
8.88
3.95
7.94
NA
3.70
13.75
38.58
2.65
43.52
7.76
Table 32-20 shows the carbonyl results for the collocated samples at DEMI. The average
concentration difference between collocated samples ranged from 0.003 ppbv (isovaleraldehyde)
to 0.31 ppbv (formaldehyde), and the average variability was 9.61 percent.
Table 32-20. Carbonyl Sampling and Analytical Precision: 8 Collocated Samples for
Detroit, MI (DEMI)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
8
8
8
8
6
0
8
8
6
8
8
8
Average RPD
(%)
9.01
8.13
24.09
7.38
9.32
NA
10.84
12.04
20.26
8.99
23.25
11.67
Average Concentration
Difference (ppbv)
0.08
0.05
0.01
0.01
0.01
NA
0.31
0.005
0.003
0.01
0.01
0.004
Coefficient of
Variation (%)
6.37
5.75
17.03
5.21
6.59
NA
7.67
8.51
14.33
6.36
16.44
8.25
32-36
-------
Table 32-21 shows the carbonyl results for the duplicate samples at GPCO. The
duplicate variability ranges from 1.32 percent (formaldehyde) to 18.86 percent
(isovaleraldehyde). The average variability is 5.90 percent, which is within the Program DQO.
Table 32-21. Carbonyl Sampling and Analytical Precision: 10 Duplicate Samples for
Grand Junction, CO (GPCO)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
10
10
10
10
10
0
10
10
6
10
10
10
Average RPD
(%)
2.64
3.34
10.57
3.95
7.02
NA
1.87
12.89
26.67
5.14
9.59
2.38
Average Concentration
Difference (ppbv)
0.03
0.05
0.01
0.004
0.01
NA
0.06
0.003
0.004
0.004
0.004
0.001
Coefficient of
Variation (%)
1.87
2.36
7.48
2.79
4.96
NA
1.32
9.12
18.86
3.63
6.78
1.68
Table 32-22 presents the carbonyl sampling and analytical precision data for collocated
samples at NBIL. The variability ranges from 29.94 percent for propionaldehyde to
66.96 percent for formaldehyde, with an average CV of 40.68 percent. All pollutants have RPD
and CV outside the Program DQO.
Table 32-22. Carbonyl Sampling and Analytical Precision: 16 Collocated Samples
for Northbrook, IL (NBIL)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Number of
Observations
16
16
16
16
16
0
16
16
2
Average RPD
(%)
44.97
72.38
76.62
47.41
50.04
NA
94.70
47.61
NA
Average Concentration
Difference (ppbv)
0.38
0.56
0.03
0.03
0.02
NA
1.24
0.02
NA
Coefficient of
Variation (%)
31.80
51.18
54.18
33.52
35.39
NA
66.96
33.66
NA
32-37
-------
Table 32-22. Carbonyl Sampling and Analytical Precision: 16 Collocated Samples
for Northbrook, IL (NBIL) (Continued)
Pollutant
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
16
16
16
Average RPD
(%)
42.34
55.40
43.89
Average Concentration
Difference (ppbv)
0.04
0.02
0.01
Coefficient of
Variation (%)
29.94
39.17
31.04
Table 32-23 shows the carbonyl results for duplicate samples at S4MO. All compounds
show a variability well within the DQO of 15 percent, with an overall average CV of
5.75 percent.
Table 32-23. Carbonyl Sampling and Analytical Precision: 14 Duplicate Samples for
St. Louis, MO (S4MO)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
14
14
14
14
12
0
14
14
8
14
14
14
Average RPD
(%)
1.93
6.16
14.97
5.87
3.70
NA
4.54
8.54
15.27
11.54
6.86
10.14
Average Concentration
Difference (ppbv)
0.03
0.06
0.01
0.002
0.002
NA
0.06
0.002
0.003
0.004
0.003
0.003
Coefficient of
Variation (%)
1.36
4.35
10.59
4.15
2.62
NA
3.21
6.04
10.80
8.16
4.85
7.17
Table 32-24 presents the carbonyl results for duplicate samples at SKFL. Two
compounds (isovaleraldehyde and tolualdehydes) are outside the specifications for RPD and CV,
with the overall average falling within the specifications. The average RPD is 14.83 percent and
the average CV is 10.49 percent.
32-38
-------
Table 32-24. Carbonyl Sampling and Analytical Precision: 12 Duplicate Samples
for Tampa, FL (SKFL)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
12
12
12
12
12
0
12
12
4
12
11
12
Average RPD
(%)
6.05
5.25
16.69
12.64
11.67
NA
5.47
13.52
30.00
10.78
45.92
5.15
Average Concentration
Difference (ppbv)
0.04
0.04
0.01
0.01
0.01
NA
0.12
0.003
0.01
0.01
0.01
0.001
Coefficient of
Variation (%)
4.28
3.71
11.80
8.94
8.25
NA
3.86
9.56
21.21
7.63
32.47
3.64
Table 32-25 shows carbonyl sampling and analytical precision data for duplicate samples
at SYFL. Only one compound (tolualdehydes) is outside the Program DQO for RPD and CV.
The average RPD is 12.35 percent and the average CV is 8.74 percent.
Table 32-25. Carbonyl Sampling and Analytical Precision: 14 Duplicate Samples for
Tampa, FL (SYFL)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
14
14
14
14
14
0
14
14
6
14
14
14
Average RPD
(%)
15.19
6.42
14.18
14.54
10.51
NA
14.43
11.20
6.39
11.43
25.42
6.19
Average Concentration
Difference (ppbv)
0.08
0.02
0.004
0.01
0.01
NA
0.23
0.004
0.001
0.01
0.01
0.002
Coefficient of
Variation (%)
10.74
4.54
10.03
10.28
7.43
NA
10.21
7.92
4.52
8.08
17.98
4.38
32-39
-------
Table 32-26 presents the average CV per pollutant, per pollutant per site, per site, and the
overall average CV. The duplicate and collocated sample results show low- to high-level
variability among the sites, ranging from an average CV of 3.80 percent at LDTN to
40.68 percent at NBIL, with an overall average of 11.30 percent. This is within the 15 percent
CV Program DQO.
Table 32-26. Carbonyl Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Analyses by Site
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Average
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Average
Average
8.77
11.37
11.52
8.45
8.96
NA
8.28
11.46
19.43
8.01
17.56
10.48
11.30
Average
8.77
11.37
11.52
8.45
8.96
NA
8.28
11.46
19.43
8.01
17.56
10.48
11.30
St. Petersburg, FL
(AZFL)
5.83
10.49
6.46
6.50
6.53
NA
1.73
9.83
37.71
2.27
12.91
19.11
10.85
Elizabeth, NJ
(ELNJ)
1.09
3.90
6.19
1.87
3.17
NA
2.19
9.91
22.45
5.17
11.23
4.59
6.52
Barceloneta, PR
(BAPR)
4.41
9.46
6.57
3.10
11.28
NA
4.87
7.97
NA
10.20
19.24
21.28
9.84
-J
u.
fg
|£
27.27
27.60
17.25
14.69
12.60
NA
1.79
18.55
32.27
11.26
31.96
18.03
19.39
Bountiful, UT
(BTUT)
2.35
6.51
8.88
3.95
7.94
NA
3.70
13.75
38.58
2.65
43.52
7.76
12. 69
J
u.
£3
o-ta
S <<
H£
17.62
12.99
14.13
15.32
11.59
NA
17.53
17.58
20.80
15.06
14.05
15.40
15.64
^
is
il
u B
2.65
6.22
5.69
6.65
3.94
NA
4.30
7.92
23.01
4.33
16.28
6.05
7.91
Grand Junction,
CO (GPCO)
1.87
2.36
7.48
2.79
4.96
NA
1.32
9.12
18.86
3.63
6.78
1.68
5.53
^
£Q
^ £
% M
SB
8.64
15.47
7.81
4.57
11.78
NA
11.38
5.20
22.32
5.99
19.26
7.27
10.88
Gulfport, MS
(GPMS)
2.29
7.96
9.55
10.23
10.64
NA
3.54
9.21
6.84
4.81
10.19
9.56
7.71
Custer, SD
(CUSD)
7.38
2.92
13.46
6.99
5.60
NA
8.53
5.54
46.06
6.04
21.60
8.62
72.07
Nashville, TN
(LDTN)
0.85
1.60
8.88
2.99
3.72
NA
1.67
6.61
2.16
1.31
9.57
2.46
3.80
Detroit, MI
(DEMI)
6.37
5.75
17.03
5.21
6.59
NA
7.67
8.51
14.33
6.36
16.44
8.25
9. 32
Nashville, XN
(MSTN)
1.40
2.46
7.38
2.76
3.50
NA
1.00
4.19
3.15
2.51
4.44
5.55
3.49
32-40
-------
Table 32-26. Carbonyl Sampling and Analytical Precision:
Coefficient of Variation for all Duplicate and Collocated Analyses by Site (Continued)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Average
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Average
Average
8.77
11.37
11.52
8.45
8.96
NA
8.28
11.46
19.43
8.01
17.56
10.48
11.30
Average
8.77
11.37
11.52
8.45
8.96
NA
8.28
11.46
19.43
8.01
17.56
10.48
11.30
Northbrook, IL
(NBIL)
31.80
51.18
54.18
33.52
35.39
NA
66.96
33.66
NA
29.94
39.17
31.04
40.68
hJ
u.
££
g H
H £
4.28
3.71
11.80
8.94
8.25
NA
3.86
9.56
21.21
7.63
32.47
3.64
10.49
New Brunswick, NJ
(NBNJ)
4.08
8.25
0.37
3.83
9.74
NA
2.59
6.05
37.22
5.08
22.53
8.74
9.86
hJ
u.
#3
s-5
s 1
E?i
9.49
6.91
6.03
11.54
8.35
NA
11.66
6.90
7.42
13.18
11.33
12.16
9.54
Orlando, J?L
(ORFL)
5.78
14.43
7.30
2.28
8.34
NA
3.33
5.64
22.69
2.24
9.76
8.24
8.18
Schiller Park, JL
(SPIL)
38.40
34.91
8.78
14.54
27.18
NA
8.49
19.35
NA
19.17
24.40
13.10
20.83
O
S
j£
'3 o"
si
*%
1.36
4.35
10.59
4.15
2.62
NA
3.21
6.04
10.80
8.16
4.85
7.17
5.75
J
u.
€\ — ^
1*
Is
10.74
4.54
10.03
10.28
7.43
NA
10.21
7.92
4.52
8.08
17.98
4.38
8.74
P
!/5
wT
13
sS
It
3.56
12.36
7.76
7.26
7.15
NA
6.83
12.28
11.73
7.48
14.00
15.35
9.61
!/5
g_
o" ^
•is
S-P
nb
1.21
21.67
12.26
7.07
4.24
NA
5.96
14.25
NA
4.25
16.13
11.76
9.88
&
a.
sS ^_
^g
aft
<% &
11.75
6.94
9.07
6.03
3.82
NA
7.61
22.47
8.75
2.68
15.28
6.37
9. 16
Austin, TX
(WETX)
15.66
10.81
24.62
22.71
6.61
NA
13.32
19.87
14.50
18.78
11.26
14.88
15.73
32-41
-------
32.1.4 Metals Sampling and Analytical Precision
The sampling and analytical variation for all collocated PMio metals samples are
presented in Table 32-27. The average CV values, as well as the average RPD values, show low
to high-level variability among the sites, with average CVs ranging from 4.76 percent for arsenic
to 49.65 percent for mercury, with an overall average at 12.67 percent.
Table 32-27. PMio Metal Sampling and Analytical Precision: 84 Collocated Samples
Pollutant
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Lead
Manganese
Mercury
Nickel
Selenium
Number of
Observations
84
84
84
84
84
84
84
84
70
84
84
Average RPD
(%)
7.15
6.74
30.75
18.86
9.70
15.17
7.82
7.56
70.21
15.03
8.07
Average Concentration
Difference (ng/m3)
0.07
0.05
0.003
0.06
0.20
0.03
0.60
0.52
0.04
0.16
0.05
Coefficient of
Variation (%)
5.06
4.76
21.74
13.34
6.86
10.73
5.53
5.35
49.65
10.63
5.70
Tables 32-28 through 32-30 present the results from collocated PMio metals at the
NATTS sites (BOMA, BTUT, and S4MO, respectively). Variability ranged from 1.26 percent
for nickel at BOMA to 55.97 percent for mercury at S4MO.
Table 32-28. PMio Metal Sampling and Analytical Precision:
54 Collocated Samples at Boston, MA (BOMA)
Pollutant
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Lead
Manganese
Mercury
Nickel
Selenium
Number of
Observations
54
54
54
54
54
54
54
54
49
54
54
Average RPD
(%)
11.97
9.90
48.30
36.80
13.64
11.23
12.49
11.39
61.27
11.66
11.20
Average
Concentration
Difference (ng/m3)
0.12
0.06
0.002
0.10
0.26
0.02
0.50
0.35
0.02
0.22
0.05
Coefficient of
Variation (%)
8.46
7.00
34.15
26.02
9.64
7.94
8.83
8.05
43.33
8.25
7.92
32-42
-------
Table 32-29. PM10 Metal Sampling and Analytical Precision:
4 Collocated Samples at Bountiful, UT (BTUT)
Pollutant
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Lead
Manganese
Mercury
Nickel
Selenium
Number of
Observations
4
4
4
4
4
4
4
4
0
4
4
Average RPD
(%)
4.41
5.28
25.26
9.52
5.97
10.48
3.66
5.05
NA
1.78
6.59
Average
Concentration
Difference (ng/m3)
0.04
0.05
0.01
0.01
0.15
0.02
0.22
0.52
NA
0.02
0.05
Coefficient of
Variation (%)
3.12
3.73
17.86
6.73
4.22
7.41
2.59
3.57
NA
1.26
4.66
Table 32-30. PMi0 Metal Sampling and Analytical Precision:
26 Collocated Samples at St. Louis, MO (S4MO)
Pollutant
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Lead
Manganese
Mercury
Nickel
Selenium
Number of
Observations
26
26
26
26
26
26
26
26
21
26
26
Average RPD
(%)
5.08
5.04
18.69
10.25
9.49
23.79
7.32
6.25
79.15
31.65
6.41
Average
Concentration
Difference (ng/m3)
0.06
0.04
0.001
0.08
0.20
0.04
1.08
0.69
0.06
0.25
0.06
Coefficient of
Variation (%)
3.59
3.56
13.21
7.25
6.71
16.82
5.18
4.42
55.97
22.38
4.53
Table 32-31 presents the average CV per pollutant, per pollutant per site, per site, and the
overall average CV. The results from collocated samples show low to high level variability
among sites, ranging from 5.52 percent at BTUT to 15.42 percent at BOMA, with an overall
average of 11.33 percent.
32-43
-------
Table 32-31. Metals Sampling and Analytical Precision:
Coefficient of Variation for all Collocated Samples by Site
Pollutant
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Lead
Manganese
Mercury
Nickel
Selenium
Average
Average
5.06
4.76
21.74
13.34
6.86
10.73
5.53
5.35
49.65
10.63
5.70
11.33
Boston, MA
(BOMA)
8.46
7.00
34.15
26.02
9.64
7.94
8.83
8.05
43.33
8.25
7.92
15.42
Bountiful, UT
(BTUT)
3.12
3.73
17.86
6.73
4.22
7.41
2.59
3.57
NA
1.26
4.66
5.52
O
S
»T
"3 o
ai
. Tf
££
3.59
3.56
13.21
7.25
6.71
16.82
5.18
4.42
55.97
22.38
4.53
13.06
32.1.5 Hexavalent Chromium Sampling and Analytical Precision
The hexavalent chromium sampling and analytical precision data is shown in
Table 32-32. The average concentration differences observed for collocated analyses of
hexavalent chromium ranged from <0.001 ng/m3 at CHSC and UNVT to 0.013 ng/m3 at BOMA.
The average RPD was lower than the Program DQO specified 25 percent, with an overall
average RPD of 8.0 percent. The RPD ranged from 0.70 percent at UNVT to 21.21 percent at
PRRI. The CV ranged from 0.50 percent at UNVT to 18.40 percent at PRRI, with an overall
average of 10.30 percent, which is within the 15 percent Program DQO.
32-44
-------
Table 32-32. Hexavalent Chromium Sampling and Analytical Precision:
Collocated Samples
Site
BTUT
BOMA
CHSC
DEMI
GPCO
HAKY
MVWI
NBIL
PRRI
PXSS
S4MO
SDGA
SYFL
UNVT
WADC
Average
Number of
Observations
98
12
12*
40
12
12*
12*
42
12*
12
12
38
14*
12*
12*
33
Average
RPD (%)
5.96
6.51
2.42
4.99
12.36
11.41
8.38
2.49
21.21
2.21
7.46
7.65
17.17
0.70
9.72
8.00
Average
Concentration
Difference
(ng/m3)
0.009
0.013
0.001
0.010
0.004
0.003
0.002
0.006
0.003
0.004
0.006
0.005
0.002
O.001
0.002
0.005
Coefficient
of Variation
(%)
17.35
16.70
1.70
14.50
14.80
15.10
5.90
10.30
18.40
2.90
13.60
11.40
5.10
0.50
6.90
10.30
* Over half of the measured detections were under the detection limit.
32.2 Analytical Precision
Analytical precision is a measurement of random errors associated with the process of
analyzing environmental samples. These errors may result from various factors, but typically
originate from random "noise" inherent to analytical instruments. Laboratories can easily
evaluate analytical precision by comparing concentrations measured during replicate analysis of
ambient air samples. The number of observations from Tables 32-29 through 32-47, in
comparison to the respective tables listed for duplicate analyses in Tables 32-2 through 32-19, is
approximately twice as high because each sample produces a replicate for each duplicate (or
collocated) sample. Overall, the replicate analyses of both duplicate and collocated samples of
VOC, SNMOC, carbonyl compounds, and hexavalent chromium suggest the analytical precision
level is within the Program DQOs.
32-45
-------
Collocated samples were collected for metals, which provide sampling and analytical
precision. However, replicate analyses were not performed for metals. Therefore, metals
analytical precision will not be discussed in this section.
32.2.1 VOC Analytical Precision
In Table 32-33, the replicate analyses of all duplicate and collocated samples show that
for most of the pollutants, the VOC analysis precision was within the Program DQO of
15 percent for CV. The precision of the VOC analytical method, in terms of average
concentration difference, ranges from 0.001 ppbv for several compounds to 1.32 ppbv for
acetonitrile. In terms of CV, the overall average variability is 18.65 percent and the median CV
is 9.11 percent. The low median CV shows that most of the pollutant variabilities are low. The
relatively high average variability is likely due to the substitution of non-detects with 1/2 the
MDL.
Table 32-33. VOC Analytical Precision:
476 Replicate Analyses for all Duplicate and Collocated Samples
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
fer/-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
Number of
Observations
347
468
376
22
0
476
0
18
0
397
396
414
476
30
288
343
476
2
2
18
2
7
7
Average RPD
(%)
11.07
7.49
10.93
36.76
22.22
7.58
3.51
23.64
NA
12.62
11.24
6.93
6.87
29.34
14.51
17.27
5.41
8.70
33.72
38.10
NA
98.99
120.38
Average
Concentration
Difference (ppbv)
1.32
0.06
0.03
0.004
0.001
0.02
0.001
0.002
NA
0.002
0.005
0.07
0.01
0.001
0.002
0.004
0.03
0.001
0.001
0.001
NA
0.01
0.001
Coefficient of
Variation (%)
7.39
5.30
7.73
25.99
15.71
5.36
2.48
16.71
NA
9.09
7.57
4.79
4.86
20.75
10.26
11.90
3.83
6.15
23.84
26.94
NA
70.00
85.12
32-46
-------
Table 32-33. VOC Analytical Precision:
476 Replicate Analyses for all Duplicate and Collocated Samples (Continued)
Pollutant
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1,3-Dichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fer/-Butyl Ether
Ethylbenzene
Hexachloro- 1 , 3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl fert-Butyl Ether
^-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
Trichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1,3,5 -Trimethy Ibenzene
Vinyl chloride
«,/?-Xylene
o-Xylene
Number of
Observations
344
476
0
13
0
5
10
459
0
0
1
475
1
11
475
30
451
362
13
92
386
476
405
5
334
476
4
474
0
119
476
476
455
410
29
476
473
Average RPD
(%)
14.25
4.64
NA
34.10
NA
160.38
31.23
9.38
NA
NA
73.22
12.88
55.18
38.90
8.58
51.02
12.42
21.01
38.87
14.85
19.06
6.61
12.56
43.01
11.98
6.96
49.63
10.16
NA
29.58
4.91
5.79
9.87
13.03
61.47
8.89
9.17
Average
Concentration
Difference (ppbv)
0.003
0.02
NA
0.002
NA
0.01
0.003
0.07
NA
NA
0.001
0.002
0.001
0.003
0.01
0.002
0.04
0.01
0.02
0.004
0.004
0.03
0.01
0.001
0.01
0.08
0.003
0.002
NA
0.002
0.01
0.01
0.01
0.003
0.001
0.02
0.01
Coefficient of
Variation (%)
10.07
3.28
NA
18.05
NA
113.41
22.08
6.63
NA
NA
51.78
9.11
39.02
27.51
5.80
36.08
8.78
14.86
27.48
9.47
13.48
4.68
8.50
30.42
8.47
4.92
35.09
7.18
NA
20.92
3.47
4.09
6.98
9.07
43.46
6.29
6.49
Table 32-34 shows the results from replicate analyses of all collocated VOC samples.
The replicate results from collocated samples show variation for the pollutants ranging from
<0.001 percent (/rami-l,2-dichloroethylene) to 0.45 percent (acetonitrile), as indicated by
32-47
-------
average concentration differences. The overall average variability is 17.50 percent, which is
slightly outside the Program DQO.
Table 32-34. VOC Analytical Precision:
182 Replicate Analyses for all Collocated Samples
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 , 3 -D ichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fert-Butyl Ether
Ethylbenzene
Hexachloro- 1 , 3 -butadiene
Number of
Observations
134
182
152
18
0
182
0
18
0
136
149
138
182
30
108
132
182
2
0
18
2
3
2
155
182
0
7
0
1
3
169
0
0
0
181
0
0
181
16
Average RPD
(%)
11.50
7.45
9.63
47.29
NA
8.08
NA
23.64
NA
17.34
8.36
6.58
7.03
37.34
13.09
9.91
5.13
15.38
NA
38.10
NA
191.92
NA
10.95
4.75
NA
7.85
NA
134.24
9.59
8.52
NA
NA
NA
9.94
NA
NA
10.01
61.30
Average
Concentration
Difference (ppbv)
0.45
0.05
0.04
0.01
NA
0.02
NA
0.002
NA
0.002
0.003
0.05
0.01
0.002
0.002
0.004
0.03
0.001
NA
0.001
NA
0.01
NA
0.003
0.02
NA
0.000
NA
0.002
O.001
0.01
NA
NA
NA
0.002
NA
NA
0.02
0.002
Coefficient of
Variation (%)
8.13
5.27
6.81
33.44
NA
5.71
NA
16.71
NA
12.26
5.91
4.30
4.97
26.41
9.26
7.01
3.62
10.88
NA
26.94
NA
135.71
NA
7.74
3.36
NA
5.55
NA
94.92
6.78
6.03
NA
NA
NA
7.03
NA
NA
6.23
43.35
32-48
-------
Table 32-34. VOC Analytical Precision:
182 Replicate Analyses for all Collocated Samples (Continued)
Pollutant
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tert-Butyl Ether
rc-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
Trichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1,3,5 -Trimethy Ibenzene
Vinyl chloride
m,p-Xylene
o-Xylene
Number of
Observations
176
141
8
12
139
182
144
5
120
182
4
180
0
58
182
182
173
164
12
182
181
Average RPD
(%)
13.21
21.22
8.23
43.61
20.29
7.16
13.71
43.01
11.82
7.08
49.63
11.95
NA
18.82
4.70
5.93
11.49
13.33
86.85
7.14
8.34
Average
Concentration
Difference (ppbv)
0.05
0.01
0.01
0.002
0.004
0.02
0.01
0.001
0.005
0.04
0.003
0.002
NA
0.002
0.01
0.01
0.01
0.002
0.003
0.02
0.01
Coefficient of
Variation (%)
9.34
15.01
5.82
44.00
14.35
5.06
9.69
30.42
8.36
5.01
35.09
8.45
NA
13.31
3.32
4.19
8.13
8.83
61.41
5.05
5.89
Table 32-35 shows the results from replicate analyses of all duplicate VOC samples. The
variation of the replicate results from the duplicate samples ranges from 1.43 percent
(chloromethylbenzene) to 119.57 percent (c/s-l,2-dichloroethylene), as represented by the CV.
The overall average variability is 16.67 percent, and the median CV is 8.34 percent.
Table 32-35. VOC Analytical Precision:
294 Replicate Analyses for all Duplicate Samples
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
Number of
Observations
213
286
224
4
Average RPD
(%)
10.85
7.51
11.53
22.72
Average
Concentration
Difference (ppbv)
1.75
0.07
0.03
0.002
Coefficient of
Variation (%)
7.02
5.31
8.15
16.06
32-49
-------
Table 32-35. VOC Analytical Precision:
294 Replicate Analyses for all Duplicate Samples (Continued)
Pollutant
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Acrylate
Ethyl fer/-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl ter/-Butyl Ether
w-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Number of
Observations
0
294
0
0
0
261
247
276
294
0
180
211
294
0
2
0
0
4
5
189
294
0
6
0
4
7
290
0
0
1
294
1
11
294
14
275
221
5
80
247
294
261
0
214
Average RPD
(%)
22.22
7.35
3.51
NA
NA
10.25
12.57
7.09
6.79
13.33
14.98
20.66
5.54
2.02
33.72
NA
NA
6.06
120.38
15.75
4.59
NA
42.85
NA
169.10
45.66
9.77
NA
NA
73.22
14.35
55.18
38.90
7.91
40.74
12.05
20.92
69.51
5.26
18.50
6.36
12.03
NA
12.04
Average
Concentration
Difference (ppbv)
0.001
0.03
0.001
NA
NA
0.002
0.01
0.08
0.01
0.001
0.002
0.004
0.04
0.001
0.001
NA
NA
0.001
0.001
0.003
0.02
NA
0.002
NA
0.02
0.004
0.10
NA
NA
0.001
0.002
0.001
0.003
0.01
0.001
0.04
0.01
0.02
0.004
0.005
0.03
0.01
NA
0.01
Coefficient of
Variation (%)
15.71
5.20
2.48
NA
NA
7.28
8.34
5.01
4.80
9.43
10.60
14.16
3.92
1.43
23.84
NA
NA
4.29
85.12
11.13
3.24
NA
22.21
NA
119.57
32.29
6.91
NA
NA
51.78
10.14
39.02
27.51
5.60
28.81
8.52
14.79
49.15
3.72
13.08
4.50
7.96
NA
8.51
32-50
-------
Table 32-35. VOC Analytical Precision:
294 Replicate Analyses for all Duplicate Samples (Continued)
Pollutant
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1,3,5 -Trimethy Ibenzene
Vinyl chloride
w,/?-Xylene
o-Xylene
Number of
Observations
294
0
294
0
61
294
294
282
246
17
294
292
Average RPD
(%)
6.90
NA
9.08
NA
34.97
5.01
5.73
9.12
12.93
53.01
9.70
9.56
Average
Concentration
Difference (ppbv)
0.09
NA
0.002
NA
0.003
0.01
0.01
0.01
0.003
0.001
0.03
0.01
Coefficient of
Variation (%)
4.88
NA
6.42
NA
24.72
3.54
4.05
6.45
9.15
37.48
6.86
6.76
Tables 32-36 through 32-40 present the precision data results from VOC replicate
analyses for all the samples taken at the NATTS sites (BTUT, DEMI, GPCO, NBIL, and S4MO,
respectively). These results show low- to high-level variability among the sites, as represented
by CV, ranging from 1.04 percent (for carbon disulfide at NBIL) to 85.12 percent (for
o-dichlorobenzene at GPCO), with an average of 9.01 percent. This is within the Program DQO
of 15 percent overall CV per site.
Table 32-36. VOC Analytical Precision:
24 Replicate Analyses for Duplicate Samples for Bountiful, TJT (BTUT)
Compound
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Number of
Observations
15
24
20
0
0
24
0
0
0
24
24
24
24
Average RPD
(%)
22.55
13.53
13.42
NA
NA
6.87
NA
NA
NA
NA
4.07
4.32
5.15
Average
Concentration
Difference (ppbv)
0.11
0.11
0.03
NA
NA
0.03
NA
NA
NA
NA
0.003
0.15
0.01
Coefficient of
Variation (%)
8.12
9.57
9.49
NA
NA
4.86
NA
NA
NA
NA
2.88
3.05
3.64
32-51
-------
Table 32-36. VOC Analytical Precision:
24 Replicate Analyses for Duplicate Samples for Bountiful, UT (BTUT) (Continued)
Pollutant
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
c/s-l,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fert-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tert-Butyl Ether
rc-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1,1,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1,3,5 -Trimethy Ibenzene
Number of
Observations
0
18
17
24
0
0
0
0
2
2
23
24
0
2
0
0
1
24
0
0
0
24
0
0
24
0
20
24
0
0
24
24
22
0
23
24
0
24
0
2
24
24
24
24
Average RPD
(%)
NA
3.17
34.80
4.89
NA
NA
NA
NA
NA
NA
9.32
4.65
NA
65.71
NA
NA
NA
6.26
NA
NA
NA
11.11
NA
NA
6.69
NA
12.84
6.08
NA
NA
5.19
4.69
22.31
NA
18.72
7.55
NA
NA
NA
66.67
4.33
6.83
10.10
9.63
Average
Concentration
Difference (ppbv)
NA
0.001
0.004
0.03
NA
NA
NA
NA
NA
NA
0.001
0.03
NA
0.005
NA
NA
0.001
0.01
NA
NA
NA
0.002
NA
NA
0.01
NA
0.05
0.003
NA
NA
0.003
0.03
0.004
NA
0.004
0.05
NA
NA
NA
0.001
0.01
0.01
0.01
0.003
Coefficient of
Variation (%)
NA
2.24
24.61
3.45
NA
NA
NA
NA
NA
NA
6.59
3.29
NA
22.21
NA
NA
NA
4.43
NA
NA
NA
7.86
NA
NA
4.73
NA
9.08
4.30
NA
NA
3.67
3.32
15.77
NA
13.24
5.34
NA
NA
NA
47.14
3.06
4.83
7.14
6.81
32-52
-------
Table 32-36. VOC Analytical Precision:
24 Replicate Analyses for Duplicate Samples for Bountiful, UT (BTUT) (Continued)
Pollutant
Vinyl chloride
m,p-Xylene
o-Xylene
Number of
Observations
2
24
24
Average RPD
(%)
NA
8.48
4.64
Average
Concentration
Difference (ppbv)
NA
0.02
0.01
Coefficient of
Variation (%)
NA
6.00
3.28
Table 32-37. VOC Analytical Precision:
32 Replicate Analyses for Collocated Samples for Detroit, MI (DEMI)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
fer/-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
m -Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
c/5-l,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
Number of
Observations
32
36
28
1
0
36
0
0
0
28
28
16
36
24
28
36
36
0
0
0
0
0
0
32
36
0
0
0
0
0
36
Average RPD
(%)
7.60
10.16
8.17
103.31
NA
7.35
NA
NA
NA
4.76
12.40
6.37
8.00
7.14
4.76
4.68
5.26
NA
NA
NA
NA
NA
NA
NA
4.98
NA
NA
NA
NA
NA
10.64
Average
Concentration
Difference (ppbv)
0.27
0.05
0.01
0.004
NA
0.02
NA
NA
NA
0.001
0.003
0.002
0.01
0.001
O.001
0.004
0.02
NA
NA
NA
NA
NA
NA
NA
0.02
NA
NA
NA
NA
NA
0.01
Coefficient of
Variation (%)
5.37
7.19
5.78
73.05
NA
5.19
NA
NA
NA
3.37
8.77
4.50
5.66
5.05
3.37
3.31
3.72
NA
NA
NA
NA
NA
NA
NA
3.52
NA
NA
NA
NA
NA
7.52
32-53
-------
Table 32-37. VOC Analytical Precision:
32 Replicate Analyses for Collocated Samples for Detroit, MI (DEMI) (Continued)
Pollutant
1 ,2-Dichloropropane
cis- 1,3-Dichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fer/-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl fert-Butyl Ether
^-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1,1,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1,3,5 -Trimethy Ibenzene
Vinyl chloride
w,£>-Xylene
o-Xylene
Number of
Observations
0
0
0
36
0
0
36
o
6
36
28
0
0
28
36
30
0
32
36
0
36
0
14
36
36
36
36
2
36
36
Average RPD
(%)
NA
NA
NA
11.11
NA
NA
5.02
20.52
6.22
9.19
NA
NA
20.29
4.69
11.26
NA
7.90
6.53
NA
6.67
NA
NA
5.11
8.65
6.04
10.26
NA
6.09
5.11
Average
Concentration
Difference (ppbv)
NA
NA
NA
0.001
NA
NA
0.003
<0.001
0.02
0.003
NA
NA
0.003
0.01
0.002
NA
0.005
0.03
NA
0.001
NA
NA
0.01
0.01
0.004
0.002
NA
0.01
0.003
Coefficient of
Variation (%)
NA
NA
NA
7.86
NA
NA
3.55
14.51
4.40
6.50
NA
NA
14.35
3.32
7.96
NA
5.59
4.62
NA
4.71
NA
NA
3.61
6.12
4.27
7.26
NA
4.30
3.61
Table 32-38. VOC Analytical Precision:
24 Replicate Analyses for Duplicate Samples for Grand Junction, CO (GPCO)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
Number of
Observations
24
24
24
0
Average RPD
(%)
16.24
5.14
15.12
NA
Average
Concentration
Difference (ppbv)
0.11
0.07
0.03
NA
Coefficient of
Variation (%)
11.49
3.63
10.69
NA
32-54
-------
Table 32-38. VOC Analytical Precision:
24 Replicate Analyses for Duplicate Samples for Grand Junction, CO (GPCO) (Continued)
Pollutant
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 ,3 -Dichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl tert-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl ter/-Butyl Ether
rc-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Number of
Observations
0
24
0
0
0
20
24
24
24
0
18
15
24
0
0
0
0
0
1
15
24
0
0
0
0
0
24
0
0
0
24
0
0
24
0
19
19
5
0
24
24
24
0
24
Average RPD
(%)
NA
4.38
NA
NA
NA
NA
13.24
5.49
5.84
NA
7.41
37.49
5.38
NA
NA
NA
NA
NA
120.38
18.81
4.67
NA
NA
NA
NA
NA
6.18
NA
NA
NA
16.67
NA
NA
8.90
NA
23.91
30.98
69.51
NA
6.83
5.54
4.37
NA
11.72
Average
Concentration
Difference (ppbv)
NA
0.02
NA
NA
NA
NA
0.01
0.08
0.01
NA
0.001
0.004
0.03
NA
NA
NA
NA
NA
0.001
0.002
0.03
NA
NA
NA
NA
NA
0.01
NA
NA
NA
0.003
NA
NA
0.01
NA
0.04
0.01
0.02
NA
0.003
0.03
0.003
NA
0.004
Coefficient of
Variation (%)
NA
3.10
NA
NA
NA
NA
9.36
3.88
4.13
NA
5.24
26.51
3.80
NA
NA
NA
NA
NA
85.12
13.30
3.30
NA
NA
NA
NA
NA
4.37
NA
NA
NA
11.79
NA
NA
6.29
NA
16.90
21.91
49.15
NA
4.83
3.92
3.09
NA
8.29
32-55
-------
Table 32-38. VOC Analytical Precision:
24 Replicate Analyses for Duplicate Samples for Grand Junction, CO (GPCO) (Continued)
Pollutant
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1,1,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethy Ibenzene
Vinyl chloride
w,/?-Xylene
o-Xylene
Number of
Observations
24
0
24
0
0
24
24
24
24
0
24
24
Average RPD
(%)
6.63
NA
3.33
NA
NA
5.62
6.50
9.72
7.57
NA
8.16
7.70
Average
Concentration
Difference (ppbv)
0.05
NA
0.001
NA
NA
0.02
0.01
0.01
0.003
NA
0.03
0.01
Coefficient of
Variation (%)
4.69
NA
2.36
NA
NA
3.98
4.59
6.87
5.35
NA
5.77
5.45
Table 32-39. VOC Analytical Precision:
24 Replicate Analyses for Collocated Samples for Northbrook, IL (NBIL)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
ter/-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
Number of
Observations
12
24
16
2
0
24
0
16
0
20
16
16
24
0
15
22
24
0
0
14
0
Average RPD
(%)
10.86
7.73
10.31
43.55
NA
9.01
NA
7.27
NA
13.33
8.33
1.47
6.92
NA
12.89
5.38
5.55
NA
NA
9.52
NA
Average
Concentration
Difference (ppbv)
0.02
0.03
0.02
0.01
NA
0.01
NA
0.002
NA
0.002
0.001
0.001
0.01
NA
0.001
0.005
0.03
NA
NA
0.001
NA
Coefficient of
Variation (%)
7.68
5.47
7.29
30.79
NA
6.37
NA
5.14
NA
9.43
5.89
1.04
4.89
NA
9.11
3.81
3.93
NA
NA
6.73
NA
32-56
-------
Table 32-39. VOC Analytical Precision:
24 Replicate Analyses for Collocated Samples for Northbrook, IL (NBIL) (Continued)
Pollutant
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
c/s-l,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 , 3 -D ichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fert-Butyl Ether
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tert-Butyl Ether
rc-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1,1,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1,3,5 -Trimethylbenzene
Vinyl chloride
w,£>-Xylene
o-Xylene
Number of
Observations
0
0
14
24
0
0
0
0
1
20
0
0
0
24
0
0
24
0
21
12
0
0
15
24
13
1
18
24
0
24
0
14
24
24
18
16
0
24
24
Average RPD
(%)
NA
NA
8.16
4.10
NA
NA
NA
NA
9.59
6.06
NA
NA
NA
22.22
NA
NA
10.98
NA
26.04
4.04
NA
NA
21.17
8.87
26.63
43.01
9.08
9.91
NA
4.21
NA
13.61
3.30
3.14
13.56
NA
NA
9.26
7.33
Average
Concentration
Difference (ppbv)
NA
NA
0.002
0.02
NA
NA
NA
NA
0.001
0.01
NA
NA
NA
0.003
NA
NA
0.003
NA
0.09
0.002
NA
NA
0.003
0.02
0.002
0.001
0.004
0.03
NA
0.002
NA
0.002
0.01
0.003
0.003
NA
NA
0.01
0.003
Coefficient of
Variation (%)
NA
NA
5.77
2.90
NA
NA
NA
NA
6.78
4.28
NA
NA
NA
15.71
NA
NA
7.76
NA
18.41
2.86
NA
NA
14.97
6.27
18.83
30.42
6.42
7.01
NA
2.98
NA
9.62
2.33
2.22
9.59
NA
NA
6.55
5.18
32-57
-------
Table 32-40. VOC Analytical Precision:
22 Replicate Analyses for Duplicate Samples for St. Louis, MO (S4MO)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
tert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
c/s-l,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 , 3 -D ichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fer/-Butyl Ether
Ethylbenzene
Hexachloro- 1 , 3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl tert-Butyl Ether
rc-Octane
Number of
Observations
12
22
16
1
0
22
0
0
0
22
22
12
22
0
16
18
22
0
1
0
0
0
0
16
22
0
0
0
0
0
22
0
0
0
22
0
0
22
2
22
18
0
0
22
Average RPD
(%)
8.67
4.22
8.81
54.16
NA
6.49
NA
NA
NA
12.12
6.23
12.41
9.61
NA
16.67
8.89
3.64
NA
59.66
NA
NA
NA
NA
5.00
3.13
NA
NA
NA
NA
NA
6.63
NA
NA
NA
12.12
NA
NA
6.06
66.67
7.43
4.41
NA
NA
6.06
Average
Concentration
Difference (ppbv)
0.19
0.02
0.02
0.003
NA
0.01
NA
NA
NA
0.002
0.002
0.01
0.01
NA
0.002
0.002
0.02
NA
0.001
NA
NA
NA
NA
0.001
0.02
NA
NA
NA
NA
NA
0.01
NA
NA
NA
0.002
NA
NA
0.01
0.001
0.04
0.003
NA
NA
0.001
Coefficient of
Variation (%)
6.13
2.98
6.23
38.30
NA
4.59
NA
NA
NA
8.57
4.41
8.77
6.80
NA
11.79
6.29
2.57
NA
42.18
NA
NA
NA
NA
3.54
2.21
NA
NA
NA
NA
NA
4.69
NA
NA
NA
8.57
NA
NA
4.28
47.14
5.25
3.11
NA
NA
4.29
32-58
-------
Table 32-40. VOC Analytical Precision:
22 Replicate Analyses for Duplicate Samples for St. Louis, MO (S4MO) (Continued)
Pollutant
Propylene
Styrene
1, 1,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1,3,5 -Trimethy Ibenzene
Vinyl chloride
«,/?-Xylene
o-Xylene
Number of
Observations
22
22
0
18
22
0
22
0
12
22
22
20
18
2
22
22
Average RPD
(%)
3.51
4.81
NA
22.65
3.30
NA
NA
NA
22.22
3.04
2.08
5.56
7.41
NA
6.24
9.36
Average
Concentration
Difference (ppbv)
0.01
0.003
NA
0.005
0.01
NA
NA
NA
0.002
0.01
0.002
0.003
0.001
NA
0.01
0.004
Coefficient of
Variation (%)
2.48
3.40
NA
16.01
2.34
NA
NA
NA
15.71
2.15
1.47
3.93
5.24
NA
4.41
6.62
Table 32-41 shows the average CV per pollutant, per pollutant per site, per site, and the
overall average CV. The average site CV ranged from 5.63 percent at MSTN to 15.90 percent at
LDTN, with an overall program average CV of 9.92 percent. This meets the 15 percent CV
Program DQO.
32-59
-------
Table 32-41. VOC Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
fer/-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
Average
7.39
5.30
7.73
25.99
NA
5.36
NA
16.71
NA
9.09
7.57
4.79
4.86
20.75
10.26
11.90
3.83
NA
NA
26.94
NA
70.00
NA
10.07
3.28
NA
18.05
NA
Barceloneta, PR
(BAPR)
4.86
3.71
16.92
6.73
NA
6.11
NA
NA
NA
3.72
4.96
2.87
4.57
NA
6.89
10.06
2.67
NA
NA
NA
NA
NA
NA
2.41
2.63
NA
NA
NA
Bountiful, UT
(BTUT)
8.12
9.57
9.49
NA
NA
4.86
NA
NA
NA
NA
2.88
3.05
3.64
NA
2.24
24.61
3.45
NA
NA
NA
NA
NA
NA
6.59
3.29
NA
22.21
NA
Camden, NJ
(CANJ)
6.82
7.53
5.02
NA
NA
5.22
NA
NA
NA
14.99
2.89
6.79
4.16
NA
18.78
8.53
3.88
NA
NA
NA
NA
NA
NA
7.91
3.70
NA
NA
NA
Chester, NJ
(CHNJ)
9.00
7.69
6.91
NA
NA
6.39
NA
NA
NA
NA
30.15
3.65
6.92
NA
15.01
5.89
4.39
NA
NA
NA
NA
NA
NA
26.37
2.37
NA
NA
NA
Custer, SD
(CUSD)
6.54
3.78
6.80
3.16
NA
4.86
NA
NA
NA
4.04
14.29
6.27
4.39
NA
15.71
19.21
3.95
NA
NA
NA
NA
NA
NA
11.79
3.78
NA
NA
NA
Detroit, MI
(DEMI)
5.37
7.19
5.78
73.05
NA
5.19
NA
NA
NA
3.37
8.77
4.50
5.66
5.05
3.37
3.31
3.72
NA
NA
NA
NA
NA
NA
NA
3.52
NA
NA
NA
Elizabeth, NJ
(ELNJ)
6.94
4.89
4.34
NA
NA
5.85
NA
NA
NA
NA
11.19
5.03
4.69
NA
11.91
15.35
5.65
NA
NA
NA
NA
NA
NA
7.67
4.37
NA
NA
NA
Grand Junction,
CO (GPCO)
11.49
3.63
10.69
NA
NA
3.10
NA
NA
NA
NA
9.36
3.88
4.13
NA
5.24
26.51
3.80
NA
NA
NA
NA
NA
85.12
13.30
3.30
NA
NA
NA
Gulfport, MS
(GPMS)
7.13
4.62
7.53
NA
NA
6.59
NA
NA
NA
5.71
3.09
5.85
5.22
NA
4.71
7.99
4.99
NA
NA
NA
NA
NA
NA
19.15
4.06
NA
NA
NA
Nashville, TN
(LDTN)
8.96
5.10
9.39
NA
NA
6.59
NA
NA
NA
20.84
4.49
2.83
7.61
NA
NA
4.82
3.69
NA
NA
NA
NA
135.71
NA
15.59
4.21
NA
NA
NA
-------
Table 32-41. VOC Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site (Continued)
Pollutant
cis- 1 ,2-Dichloroethylene
fra«5-l,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 , 3 -D ichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fer/-Butyl Ether
Ethylbenzene
Hexachloro- 1 , 3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl fert-Butyl Ether
^-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
Tetrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
rrichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
Average
113.41
22.08
6.63
NA
NA
51.78
9.11
39.02
27.51
5.80
36.08
8.78
14.86
27.48
9.47
13.48
4.68
8.50
30.42
8.47
4.92
35.09
7.18
NA
20.92
3.47
4.09
6.98
Barceloneta, PR
(BAPR)
NA
NA
2.91
NA
NA
NA
3.93
NA
27.51
5.46
NA
17.35
20.69
NA
1.57
33.24
3.55
13.65
NA
17.33
4.90
NA
8.64
NA
NA
2.22
2.71
5.03
Bountiful, UT
(BTUT)
NA
NA
4.43
NA
NA
NA
7.86
NA
NA
4.73
NA
9.08
4.30
NA
NA
3.67
3.32
15.77
NA
13.24
5.34
NA
NA
NA
47.14
3.06
4.83
7.14
Camden, NJ
(CANJ)
NA
NA
5.01
NA
NA
NA
6.73
39.02
NA
4.44
NA
6.91
7.59
NA
3.92
14.37
4.59
4.08
NA
7.61
8.18
NA
8.08
NA
12.57
3.69
6.09
8.60
Chester, NJ
(CHNJ)
NA
NA
12.21
NA
NA
NA
10.10
NA
NA
6.31
23.57
6.71
29.04
NA
3.21
10.77
7.66
5.24
NA
6.84
3.54
NA
8.08
NA
NA
3.64
3.17
4.29
Custer, SD
(CUSD)
116.09
4.16
5.27
NA
NA
NA
16.84
NA
NA
6.95
NA
12.50
17.21
NA
NA
4.58
4.40
7.22
NA
10.33
4.12
NA
3.37
NA
7.86
4.24
4.12
6.28
Detroit, MI
(DEMI)
NA
NA
7.52
NA
NA
NA
7.86
NA
NA
3.55
14.51
4.40
6.50
NA
NA
14.35
3.32
7.96
NA
5.59
4.62
NA
4.71
NA
NA
3.61
6.12
4.27
Elizabeth, NJ
(ELNJ)
NA
NA
5.95
NA
NA
NA
6.73
NA
NA
2.17
NA
7.12
18.91
NA
6.44
6.71
6.20
12.60
NA
2.84
4.95
NA
10.77
NA
8.49
4.10
5.33
3.57
Grand Junction,
CO (GPCO)
NA
NA
4.37
NA
NA
NA
11.79
NA
NA
6.29
NA
16.90
21.91
49.15
NA
4.83
3.92
3.09
NA
8.29
4.69
NA
2.36
NA
NA
3.98
4.59
6.87
Gulfport, MS
(GPMS)
NA
NA
8.83
NA
NA
NA
13.47
NA
NA
5.81
NA
5.93
10.72
NA
NA
9.63
4.59
5.36
NA
1.29
4.65
NA
4.04
NA
NA
5.00
5.01
15.47
Nashville, TN
(LDTN)
NA
NA
5.31
NA
NA
NA
7.86
NA
NA
9.51
101.39
6.13
8.27
NA
NA
16.84
6.59
2.17
NA
NA
5.01
NA
21.80
NA
NA
4.53
3.22
16.30
-------
Table 32-41. VOC Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site (Continued)
Pollutant
1 ,3 ,5-Trimethylbenzene
Vinyl chloride
w,/?-Xylene
o-Xylene
Average
Average
9. 07
43.46
6.29
6.49
9.92
*
a.
<&
-*^
0)
a _
O 'mS
O PH
M &
8.40
NA
4.85
6.35
8.16
H
P
s ^
"S p
S H
M S
6.81
NA
6.00
3.28
8.47
^
^
S '^
"5 Z
a -^j
u B
4.04
30.67
6.35
9.22
8.76
Z
^
o3 ^
"S ^
o hrl
S ^
18.72
NA
9.55
6.46
9.80
Q
t£3
!-" S
^ tf>
•S p
u B
15.44
NA
4.70
11.16
11.04
hH
^
^ £7
o ^
•^ H
p S
7.26
NA
4.30
3.61
7.87
i_j
Z
^
aj O
"s Z
g hJ
W &
3.46
NA
4.81
7.18
6.97
a
.2
lo
H^
« »l
a S
~ o
O U
5.35
NA
5.77
5.45
11.39
C/5
S
t ^"^
O ^
o, ^
a ^
O 9>
6.73
20.44
6.30
4.41
7.24
z
H
^
—•
"" Z^
£ H
a O
z td
12.26
NA
4.61
12.27
15.80
to
ON
to
Table 32-41. VOC Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site (Continued)
Pollutant
Acetonitrile
Acetylene
Acrolein
Acrylonitrile
fert-Amyl Methyl Ether
Benzene
Bromochloromethane
Bromodichloromethane
Bromoform
Bromomethane
Average
7.39
5.30
7.73
25.99
NA
5.36
NA
16.71
NA
9.09
Nashville, TN
(MSTN)
5.61
3.29
3.77
NA
NA
4.24
NA
NA
NA
NA
Northbrook, IL
(NBIL)
7.68
5.47
7.29
30.79
NA
6.37
NA
5.14
NA
9.43
New Brunswick,
NJ (NBNJ)
NA
5.31
4.25
NA
15.71
5.70
2.48
NA
NA
9.43
O
S
•V
%
'3 o"
a!
. Tf
£&
6.13
2.98
6.23
38.30
NA
4.59
NA
NA
NA
8.57
0
!/5
•V
%
"3
ta K
gS
o fe
a sa
7.82
5.49
15.66
NA
NA
4.49
NA
NA
NA
NA
San Juan, PR
(SJPR)
5.61
5.23
9.81
NA
NA
6.87
NA
NA
NA
NA
Schiller Park IL
(SPIL)
15.87
6.23
9.56
25.24
NA
6.74
NA
28.28
NA
NA
!/5
s
it
H=e
3.81
4.57
2.31
NA
NA
2.94
NA
NA
NA
4.47
Austin, TX
(WETX)
5.30
4.35
5.08
4.67
NA
5.15
NA
NA
NA
15.40
-------
Table 32-41. VOC Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site (Continued)
Pollutant
1,3 -Butadiene
Carbon disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Chloromethylbenzene
Chloroprene
Dibromochloromethane
1 ,2-Dibromoethane
w-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
Dichlorodifluoromethane
1 , 1 -Dichloroethane
1 ,2-Dichloroethane
1 , 1 -Dichloroethene
cis- 1 ,2-Dichloroethylene
trans- 1 ,2-Dichloroethylene
Dichloromethane
1 ,2-Dichloropropane
cis- 1 , 3 -Dichloropropene
trans- 1 ,3 -Dichloropropene
Dichlorotetrafluoroethane
Ethyl Aery late
Ethyl fer/-Butyl Ether
Average
7.57
4.79
4.86
20.75
10.26
11.90
3.83
NA
NA
26.94
NA
70.00
NA
10.07
3.28
NA
18.05
NA
113.41
22.08
6.63
NA
NA
51.78
9.11
39.02
27.51
Nashville, TN
(MSTN)
1.96
2.01
1.09
NA
NA
3.54
2.72
NA
NA
NA
NA
NA
NA
5.55
2.09
NA
NA
NA
NA
NA
1.66
NA
NA
NA
4.71
NA
NA
Northbrook, IL
(NBIL)
5.89
1.04
4.89
NA
9.11
3.81
3.93
NA
NA
6.73
NA
NA
NA
5.77
2.90
NA
NA
NA
NA
6.78
4.28
NA
NA
NA
15.71
NA
NA
New Brunswick,
NJ (NBNJ)
5.89
2.68
5.99
9.43
6.67
24.78
3.15
1.43
NA
NA
NA
4.29
NA
17.34
1.81
NA
22.21
NA
128.16
3.63
3.75
NA
NA
51.78
4.29
NA
NA
O
S
j£
'3 o"
si
*%
4.41
8.77
6.80
NA
11.79
6.29
2.57
NA
42.18
NA
NA
NA
NA
3.54
2.21
NA
NA
NA
NA
NA
4.69
NA
NA
NA
8.57
NA
NA
0
!/5
»T
13
^«
le
a &
13.47
6.31
3.44
NA
9.43
17.68
4.22
NA
5.50
NA
NA
NA
NA
NA
3.80
NA
22.21
NA
114.46
NA
7.09
NA
NA
NA
23.57
NA
NA
C£
a.
sS _
%&
\*
<% Q
4.06
5.89
3.85
NA
NA
7.73
5.11
NA
NA
NA
NA
NA
NA
6.41
4.11
NA
NA
NA
NA
89.07
6.43
NA
NA
NA
7.86
NA
NA
Schiller Park IL
(SPIL)
6.10
4.34
4.85
NA
3.21
11.68
4.36
NA
NA
47.14
NA
NA
NA
6.73
4.33
NA
NA
NA
NA
6.78
7.14
NA
NA
NA
4.29
NA
NA
!/5
g
if
Ib
1.75
4.14
4.66
NA
18.78
9.43
3.12
NA
NA
NA
NA
NA
NA
NA
2.73
NA
NA
NA
NA
NA
18.88
NA
NA
NA
NA
NA
NA
Austin, TX
(WETX)
8.24
11.05
5.73
47.76
21.34
14.88
3.33
10.88
NA
NA
NA
NA
NA
5.06
3.10
NA
5.55
NA
94.92
NA
10.26
NA
NA
NA
1.75
NA
NA
to
-------
Table 32-41. VOC Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site (Continued)
Pollutant
Ethylbenzene
Hexachloro- 1 ,3 -butadiene
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methyl Methacrylate
Methyl fert-Butyl Ether
rc-Octane
Propylene
Styrene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
Toluene
1 ,2,4-Trichlorobenzene
1,1,1 -Trichloroethane
1 , 1 ,2-Trichloroethane
Trichloroethylene
rrichlorofluoromethane
rrichlorotrifluoroethane
1 ,2,4-Trimethylbenzene
1,3,5 -Trimethy Ibenzene
Vinyl chloride
w,/?-Xylene
o-Xylene
Average
Average
5.80
36.08
8.78
14.86
27.48
9.47
13.48
4.68
8.50
30.42
8.47
4.92
35.09
7.18
NA
20.92
3.47
4.09
6.98
9.07
43.46
6.29
6.49
9.92
Nashville, TN
(MSTN)
4.85
NA
3.46
23.81
NA
NA
9.42
5.58
4.50
NA
16.25
4.29
NA
2.83
NA
17.41
2.36
2.94
2.57
11.79
NA
4.82
4.23
5.63
Northbrook, IL
(NBIL)
7.76
NA
18.41
2.86
NA
NA
14.97
6.27
18.83
30.42
6.42
7.01
NA
2.98
NA
9.62
2.33
2.22
9.59
NA
NA
6.55
5.18
8.41
New Brunswick,
NJ (NBNJ)
3.91
15.71
2.92
15.15
NA
0.65
13.62
3.19
11.10
NA
4.40
7.51
NA
9.43
NA
12.55
1.71
3.58
2.24
17.59
NA
6.78
3.59
11.60
O
s
j£
'3 o"
si
*%
4.28
47.14
5.25
3.11
NA
NA
4.29
2.48
3.40
NA
16.01
2.34
NA
NA
NA
15.71
2.15
1.47
3.93
5.24
NA
4.41
6.62
8.98
Q
!/5
»T
13
^«
le
a &
7.86
NA
7.81
34.47
NA
NA
37.70
6.04
9.13
NA
10.83
3.23
NA
7.07
NA
NA
4.44
6.64
11.90
8.51
NA
13.11
11.90
14.36
&
a.
sS _
%&
\*
<% Q
8.32
NA
7.12
5.58
NA
6.51
9.37
4.38
6.89
NA
8.51
6.93
NA
NA
NA
6.43
5.17
2.18
7.09
9.45
61.33
7.07
7.47
10.90
Schiller Park IL
(SPIL)
7.92
NA
19.13
35.34
NA
NA
23.19
5.28
2.53
NA
7.94
4.74
NA
8.69
NA
9.46
4.03
5.22
11.30
NA
NA
6.24
6.57
10.92
!/5
g
if
Ib
6.22
NA
5.17
3.57
NA
NA
17.28
4.13
5.89
NA
3.16
3.06
NA
2.36
NA
87.05
2.64
2.92
1.45
NA
NA
9.41
4.80
8.60
Austin, TX
(WETX)
3.77
14.14
4.52
13.28
5.82
44.00
7.30
3.33
22.18
NA
5.59
4.39
35.09
9.70
NA
16.74
3.08
5.42
4.73
4.02
61.41
3.78
3.50
13.65
to
-------
32.2.2 SNMOC Analytical Precision
Table 32-42 presents replicate analytical data for all duplicate and collocated SNMOC
samples. The average concentration differences observed for replicate analyses of SNMOC
ranged from 0.03 (several individual compounds) to 17.26 (TNMOC) ppbC. For most of the
pollutants, the SNMOC precision was within the Program DQO of 15 percent. The overall
average variability is 11.27 percent.
Table 32-42. SNMOC Analytical Precision:
128 Replicate Analyses for all Duplicate and Collocated Samples
Pollutant
Acetylene
Benzene
1,3 -Butadiene
^-Butane
c/s-2-Butene
fra«s-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
rc-Decane
1-Decene
w-Diethylbenzene
p-Diethylbenzene
2,2-Dimethylbutane
2,3 -Dimethy Ibutane
2,3 -Dimethy Ipentane
2,4-Dimethylpentane
rc-Dodecane
1-Dodecene
Ethane
Ethylbenzene
2-Ethyl-l-butene
Ethylene
w-Ethyltoluene
o-Ethyltoluene
p-Ethyltoluene
^-Heptane
1-Heptene
rc-Hexane
1-Hexene
c/s-2-Hexene
fra»s-2-Hexene
Number of
Observations
128
128
53
128
101
101
119
118
45
112
1
67
58
123
117
122
121
59
25
125
128
0
123
123
98
119
124
87
128
109
5
11
Average RPD
(%)
5.02
6.13
13.07
4.05
12.07
12.36
10.56
11.48
25.32
13.81
30.59
25.27
34.30
10.53
8.52
8.18
11.95
34.29
37.03
9.56
13.41
NA
11.85
10.65
13.90
15.55
8.05
17.07
6.35
14.32
41.89
44.85
Average
Concentration
Difference (ppbC)
0.09
0.09
0.03
0.16
0.03
0.03
0.04
0.11
0.09
0.07
0.07
0.12
0.07
0.04
0.03
0.05
0.04
0.19
0.12
0.41
0.07
NA
0.29
0.05
0.05
0.04
0.05
0.03
0.08
0.04
0.10
0.08
Coefficient of
Variation (%)
3.55
4.34
9.24
2.86
8.53
8.74
7.47
8.12
17.90
9.76
21.63
17.87
24.25
7.45
6.02
5.79
8.45
24.25
26.19
6.76
9.48
NA
8.38
7.53
9.83
11.00
5.69
12.07
4.49
10.12
29.62
31.71
32-65
-------
Table 32-42. SNMOC Analytical Precision:
128 Replicate Analyses for all Duplicate and Collocated Samples (Continued)
Pollutant
Isobutane
lsobutene/1 -Butene
Isopentane
Isoprene
Isopropylbenzene
2-Methyl-l-butene
2-Methyl-2-butene
3 -Methyl- 1 -butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2-Methylhexane
3-Methylhexane
3-Methylpentane
2-Methylpentane
4-Methyl-l-pentene
2-Methyl-l-pentene
rc-Nonane
1-Nonene
^-Octane
1-Octene
rc-Pentane
1-Pentene
c/s-2-Pentene
fra»s-2-Pentene
a-Pinene
&-Pinene
Propane
rc-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
TNMOC (w/unknowns)
Toluene
rc-Tridecane
1-Tridecene
1,2,3-Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 ,3 ,5-Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3 ,4-Trimethylpentane
Number of
Observations
128
122
122
111
60
104
102
o
6
125
128
119
106
104
127
128
124
11
20
120
83
124
58
128
114
90
115
102
17
128
100
128
0
75
128
128
128
9
0
105
124
105
76
128
116
Average RPD
(%)
1.77
4.30
2.98
9.60
25.26
11.55
19.58
62.55
9.33
7.31
10.69
13.42
10.91
9.50
6.88
7.73
24.30
16.02
13.12
29.07
7.84
22.04
3.62
11.74
17.17
11.74
11.16
27.47
1.23
19.58
4.07
NA
30.65
5.42
4.70
5.93
60.85
NA
25.27
9.88
15.77
31.05
8.59
10.17
Average
Concentration
Difference (ppbC)
0.06
0.05
0.33
0.05
0.04
0.07
0.04
0.23
0.08
0.05
0.03
0.03
0.06
0.11
0.05
0.18
0.07
0.03
0.04
0.06
0.04
0.05
1.12
0.04
0.03
0.03
0.10
0.11
0.12
0.04
0.04
NA
0.34
17.26
8.20
0.26
0.33
NA
0.07
0.07
0.03
0.07
0.08
0.03
Coefficient of
Variation (%)
1.26
3.04
2.11
6.79
17.86
8.16
13.85
44.23
6.60
5.17
7.56
9.49
7.71
6.71
4.86
5.47
17.18
11.33
9.28
20.55
5.54
15.58
2.56
8.30
12.14
8.30
7.89
19.43
0.87
13.85
2.88
NA
21.67
3.83
3.32
4.19
43.03
NA
17.87
6.99
11.15
21.96
6.08
7.19
32-66
-------
Table 32-42. SNMOC Analytical Precision:
128 Replicate Analyses for all Duplicate and Collocated Samples (Continued)
Pollutant
rc-Undecane
1-Undecene
m -Xylene/p-Xy lene
o-Xylene
Number of
Observations
82
33
128
125
Average RPD
(%)
16.96
32.80
8.71
12.11
Average
Concentration
Difference (ppbC)
0.16
0.13
0.14
0.06
Coefficient of
Variation (%)
11.99
23.20
6.16
8.57
Table 32-43 presents results from SNMOC replicate analyses for all of the duplicate
samples. These results show low- to high-level variability, ranging from 0.77 percent (propane)
to 44.23 percent (3-methyl-1-butene). The overall average variability is 10.86 percent.
Table 32-43. SNMOC Analytical Precision:
104 Replicate Analyses for all Duplicate Samples
Pollutant
Acetylene
Benzene
1,3 -Butadiene
rc-Butane
c/s-2-Butene
fra»s-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
rc-Decane
1-Decene
w-Diethylbenzene
p-Diethylbenzene
2,2-Dimethylbutane
2,3 -Dimethy Ibutane
2,3 -Dimethy Ipentane
2,4-Dimethylpentane
rc-Dodecane
1-Dodecene
Ethane
Ethylbenzene
2-Ethyl- 1-butene
Number of
Observations
104
104
47
104
85
85
97
96
36
90
1
50
48
101
94
100
97
45
14
101
104
0
Average RPD
(%)
5.43
5.37
13.23
3.07
11.45
11.21
10.90
12.38
25.27
13.83
30.59
23.54
34.36
10.09
7.14
8.56
13.12
35.77
38.43
11.56
14.09
NA
Average
Concentration
Difference (ppbC)
0.11
0.09
0.04
0.16
0.03
0.04
0.04
0.13
0.10
0.05
0.07
0.10
0.08
0.04
0.03
0.04
0.05
0.23
0.13
0.48
0.08
NA
Coefficient of
Variation (%)
3.84
3.79
9.36
2.17
8.10
7.92
7.70
8.75
17.87
9.78
21.63
16.65
24.29
7.13
5.05
6.05
9.27
25.29
27.18
8.18
9.96
NA
32-67
-------
Table 32-43. SNMOC Analytical Precision:
104 Replicate Analyses for all Duplicate Samples (Continued)
Pollutant
Ethylene
w-Ethy toluene
o-Ethyltoluene
p-Ethyltoluene
^-Heptane
1-Heptene
rc-Hexane
1-Hexene
c/s-2-Hexene
fra»s-2-Hexene
Isobutane
lsobutene/1 -Butene
Isopentane
Isoprene
Isopropylbenzene
2-Methyl-l-butene
2-Methyl-2-butene
3 -Methyl- 1 -butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2-Methylhexane
3 -Methy Ihexane
3-Methylpentane
2-Methylpentane
4-Methyl-l-pentene
2-Methyl-l-pentene
rc-Nonane
1-Nonene
rc-Octane
1-Octene
rc-Pentane
1-Pentene
c/s-2-Pentene
fra«s-2-Pentene
a-Pinene
&-Pinene
Propane
w-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
Number of
Observations
99
100
76
96
100
74
104
95
5
10
104
100
100
93
53
85
88
o
J
102
104
97
86
85
103
104
104
11
18
97
70
102
47
104
90
77
93
84
17
104
83
104
0
70
104
Average RPD
(%)
13.98
9.31
12.54
14.32
6.77
15.34
5.86
15.39
41.89
44.85
1.57
4.05
2.98
9.63
24.82
10.89
16.58
62.55
8.99
8.01
10.51
13.10
10.99
9.99
6.42
8.72
24.30
17.34
12.18
29.07
7.34
24.48
3.49
13.02
14.69
10.62
11.73
27.47
1.09
22.59
4.03
NA
21.60
2.89
Average
Concentration
Difference (ppbC)
0.32
0.04
0.05
0.04
0.04
0.03
0.08
0.04
0.10
0.07
0.06
0.05
0.36
0.06
0.03
0.07
0.03
0.23
0.08
0.05
0.03
0.03
0.07
0.12
0.05
0.18
0.07
0.04
0.04
0.06
0.04
0.06
1.38
0.04
0.03
0.03
0.12
0.11
0.12
0.04
0.04
NA
0.11
3.98
Coefficient of
Variation (%)
9.89
6.58
8.87
10.13
4.79
10.84
4.15
10.88
29.62
31.71
1.11
2.86
2.11
6.81
17.55
7.70
11.72
44.23
6.36
5.66
7.43
9.27
7.77
7.06
4.54
6.16
17.18
12.26
8.61
20.56
5.19
17.31
2.47
9.21
10.39
7.51
8.30
19.43
0.77
15.97
2.85
NA
15.27
2.04
32-68
-------
Table 32-43. SNMOC Analytical Precision:
104 Replicate Analyses for all Duplicate Samples (Continued)
Pollutant
TNMOC (w/unknowns)
Toluene
rc-Tridecane
1-Tridecene
1 ,2,3 -Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3,4-Trimethylpentane
rc-Undecane
1-Undecene
m -Xylene/^-Xy lene
o-Xylene
Number of
Observations
104
104
8
0
89
100
87
58
104
92
64
27
104
102
Average RPD
(%)
4.87
4.74
37.60
NA
22.43
10.63
17.54
34.25
9.19
10.75
18.42
21.64
8.36
10.67
Average
Concentration
Difference (ppbC)
8.43
0.26
0.37
NA
0.05
0.08
0.03
0.08
0.08
0.04
0.19
0.09
0.14
0.06
Coefficient of
Variation (%)
3.44
3.35
26.59
NA
15.86
7.51
12.40
24.22
6.50
7.60
13.03
15.30
5.91
7.55
Table 32-44 through 32-45 present the results from SNMOC replicate analyses for all the
duplicate and collocated samples at NATTS sites (BTUT and NBIL). These results show low- to
high-level variability at these sites, as represented by CV, ranging from 0.34 percent (for
isobutane at BTUT) to 75.91 percent (for w-tridecane at NBIL), with an average of 10.49 percent.
This is within the 15 percent Program DQO.
Table 32-44. SNMOC Analytical Precision:
56 Replicate Analyses for Duplicate Samples for Bountiful, UT (BTUT)
Pollutant
Acetylene
Benzene
1,3 -Butadiene
rc-Butane
c/s-2-Butene
fra«5-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
rc-Decane
1-Decene
Number of
Observations
24
24
14
24
24
24
24
24
9
24
1
Average RPD
(%)
8.52
5.74
5.94
0.83
8.85
18.21
5.48
6.00
64.19
12.93
30.59
Average
Concentration
Difference (ppbC)
0.22
0.11
0.01
0.10
0.03
0.05
0.04
0.02
0.17
0.04
0.07
Coefficient of
Variation (%)
6.03
4.06
4.20
0.59
6.26
12.88
3.87
4.25
45.39
9.14
21.63
32-69
-------
Table 32-44. SNMOC Analytical Precision:
56 Replicate Analyses for Duplicate Samples for Bountiful, UT (BTUT) (Continued)
Pollutant
w-Diethylbenzene
p-Diethylbenzene
2,2-Dimethylbutane
2,3-Dimethylbutane
2,3-Dimethylpentane
2,4-Dimethylpentane
rc-Dodecane
1-Dodecene
Ethane
Ethylbenzene
2-Ethyl-l-butene
Ethylene
w-Ethyltoluene
o-Ethyltoluene
p-Ethyltoluene
^-Heptane
1-Heptene
rc-Hexane
1-Hexene
c/s-2-Hexene
fraws-2-Hexene
Isobutane
lsobutene/1 -Butene
Isopentane
Isoprene
Isopropylbenzene
2-Methyl-l-butene
2-Methyl-2-butene
3 -Methyl- 1 -butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2-Methylhexane
3-Methylhexane
3-Methylpentane
2-Methylpentane
4-Methyl- 1 -pentene
2-Methyl- 1 -pentene
w-Nonane
1-Nonene
^-Octane
1-Octene
rc-Pentane
Number of
Observations
12
10
24
24
24
24
10
o
5
23
24
0
21
24
24
24
24
22
24
24
2
0
24
24
24
22
12
24
24
0
24
24
24
24
24
24
24
24
2
4
24
22
24
11
24
Average RPD
(%)
15.54
31.52
9.15
6.29
4.72
10.07
29.65
36.59
26.75
9.06
NA
18.57
9.21
15.73
12.74
6.00
12.63
4.40
16.73
80.58
NA
0.48
3.86
0.90
12.62
16.49
11.93
11.97
NA
6.60
4.91
9.11
8.41
14.82
4.92
3.31
4.04
14.96
4.78
14.08
40.56
4.62
15.16
2.46
Average
Concentration
Difference (ppbC)
0.03
0.05
0.05
0.05
0.05
0.06
0.11
0.10
1.02
0.06
NA
0.36
0.05
0.04
0.04
0.07
0.04
0.10
0.05
0.13
NA
0.04
0.06
0.10
0.05
0.03
0.06
0.04
NA
0.10
0.06
0.03
0.03
0.11
0.10
0.05
0.12
0.03
0.004
0.04
0.06
0.03
0.03
0.18
Coefficient of
Variation (%)
10.99
22.29
6.47
4.45
3.34
7.12
20.97
25.87
18.92
6.41
NA
13.13
6.51
11.12
9.01
4.25
8.93
3.11
11.83
56.98
NA
0.34
2.73
0.63
8.93
11.66
8.44
8.47
NA
4.67
3.47
6.44
5.95
10.48
3.48
2.34
2.86
10.58
3.38
9.96
28.68
3.27
10.72
1.74
32-70
-------
Table 32-44. SNMOC Analytical Precision:
56 Replicate Analyses for Duplicate Samples for Bountiful, UT (BTUT) (Continued)
Pollutant
1-Pentene
c/s-2-Pentene
fra«s-2-Pentene
a-Pinene
&-Pinene
Propane
rc-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
TNMOC (w/unknowns)
Toluene
rc-Tridecane
1-Tridecene
1 ,2,3 -Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3,4-Trimethylpentane
rc-Undecane
1-Undecene
m -Xy lene/^-Xy lene
o-Xylene
Number of
Observations
21
24
24
17
2
24
24
24
0
16
24
24
24
2
0
24
24
24
19
24
24
16
o
5
24
24
Average RPD
(%)
11.44
11.35
8.34
13.85
28.65
0.72
18.71
2.29
NA
27.86
3.39
3.86
4.93
50.21
NA
17.95
9.18
13.85
16.32
6.10
8.64
17.02
12.20
6.61
7.12
Average
Concentration
Difference (ppbC)
0.04
0.02
0.03
0.06
0.06
0.10
0.04
0.05
NA
0.11
3.51
5.75
0.21
0.59
NA
0.03
0.07
0.04
0.04
0.08
0.04
0.04
0.02
0.15
0.05
Coefficient of
Variation (%)
8.09
8.03
5.90
9.79
20.26
0.51
13.23
1.62
NA
19.70
2.40
2.73
3.48
35.51
NA
12.69
6.49
9.79
11.54
4.31
6.11
12.03
8.63
4.67
5.04
Table 32-45. SNMOC Analytical Precision:
24 Replicate Analyses for Collocated Samples for Northbrook, IL (NBIL)
Pollutant
Acetylene
Benzene
1,3 -Butadiene
^-Butane
c/s-2-Butene
fraws-2-Butene
Cyclohexane
Cyclopentane
Number of
Observations
24
24
6
24
16
16
22
22
Average RPD
(%)
3.42
9.20
12.40
7.96
14.53
17.00
9.22
7.91
Average
Concentration
Difference (ppbC)
0.03
0.09
0.01
0.15
0.03
0.03
0.03
0.02
Coefficient of
Variation (%)
2.42
6.50
8.77
5.63
10.27
12.02
6.52
5.59
32-71
-------
Table 32-45. SNMOC Analytical Precision:
24 Replicate Analyses for Collocated Samples for Northbrook, IL (NBIL) (Continued)
Pollutant
Cyclopentene
n-Decane
1-Decene
m -Diethy Ibenzene
p-Diethy Ibenzene
2,2-Dimethylbutane
2,3-Dimethylbutane
2,3-Dimethylpentane
2,4-Dimethylpentane
rc-Dodecane
1-Dodecene
Ethane
Ethy Ibenzene
2-Ethyl-l-butene
Ethylene
w-Ethyltoluene
o-Ethyltoluene
p-Ethyltoluene
^-Heptane
1-Heptene
rc-Hexane
1-Hexene
c/s-2-Hexene
trans-2-Rexene
Isobutane
lsobutene/1 -Butene
Isopentane
Isoprene
Isopropy Ibenzene
2-Methyl-l-butene
2-Methyl-2-butene
3 -Methyl- 1 -butene
Methylcyclohexane
Methylcyclopentane
2-Methylheptane
3-Methylheptane
2-Methylhexane
3 -Methy Ihexane
3-Methylpentane
2-Methylpentane
4-Methyl-l-pentene
2-Methyl-l-pentene
rc-Nonane
1-Nonene
Number of
Observations
9
22
0
17
10
22
23
22
24
14
11
24
24
0
24
23
22
23
24
13
24
14
0
1
24
22
22
18
7
19
14
0
23
24
22
20
19
24
24
20
0
2
23
13
Average RPD
(%)
25.50
13.74
NA
32.16
34.07
12.31
14.00
6.68
7.26
28.41
32.83
1.57
10.69
NA
3.31
16.02
19.34
20.48
13.16
24.02
8.28
10.03
NA
NA
2.59
5.33
2.95
9.48
26.98
14.15
31.60
NA
10.70
4.50
11.41
14.70
10.59
7.52
8.72
3.79
NA
12.05
16.89
29.03
Average
Concentration
Difference (ppbC)
0.06
0.13
NA
0.17
0.07
0.03
0.03
0.05
0.02
0.06
0.09
0.14
0.03
NA
0.13
0.05
0.05
0.04
0.07
0.03
0.08
0.02
NA
0.11
0.04
0.05
0.18
0.04
0.05
0.09
0.06
NA
0.05
0.03
0.02
0.03
0.05
0.09
0.04
0.16
NA
0.01
0.04
0.07
Coefficient of
Variation (%)
18.03
9.71
NA
22.74
24.09
8.70
9.90
4.72
5.13
20.09
23.21
1.11
7.56
NA
2.34
11.33
13.68
14.48
9.31
16.99
5.86
7.09
NA
NA
1.83
3.77
2.09
6.70
19.08
10.01
22.34
NA
7.57
3.18
8.07
10.39
7.49
5.32
6.17
2.68
NA
8.52
11.94
20.53
32-72
-------
Table 32-45. SNMOC Analytical Precision:
24 Replicate Analyses for Collocated Samples for Northbrook, IL (NBIL) (Continued)
Pollutant
rc-Octane
1-Octene
rc-Pentane
1-Pentene
c/s-2-Pentene
fra«5-2-Pentene
a-Pinene
&-Pinene
Propane
rc-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
TNMOC (w/unknowns)
Toluene
rc-Tridecane
1-Tridecene
1 ,2,3 -Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 , 3 ,5 -Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3,4-Trimethylpentane
rc-Undecane
1-Undecene
m -Xylene/^-Xy lene
o-Xylene
Number of
Observations
22
11
24
24
13
22
18
0
24
17
24
0
5
24
24
24
1
0
16
24
18
18
24
24
18
6
24
23
Average RPD
(%)
9.85
12.28
4.13
6.59
27.07
16.21
8.85
NA
1.81
7.56
4.22
NA
66.86
15.54
4.03
10.68
107.36
NA
36.59
6.90
8.73
18.25
6.23
7.86
11.13
66.28
10.12
17.88
Average
Concentration
Difference (ppbC)
0.04
0.03
0.08
0.02
0.03
0.03
0.04
NA
0.11
0.02
0.04
NA
1.25
70.37
7.27
0.25
0.25
NA
0.13
0.04
0.03
0.05
0.06
0.02
0.06
0.25
0.13
0.06
Coefficient of
Variation (%)
6.97
8.68
2.92
4.66
19.14
11.46
6.25
NA
1.28
5.34
2.99
NA
47.28
10.99
2.85
7.55
75.91
NA
25.88
4.88
6.17
12.90
4.40
5.56
7.87
46.87
7.15
12.64
Table 32-46 presents the average CV per pollutant, per pollutant per site, per site, and the
overall average CV. The average site CV ranged from 8.83 percent at CUSD to 11.27 percent at
NBIL, with an overall program average CV of 10.28 percent. This overall average variability is
within the 15 percent CV Program DQO.
32-73
-------
Table 32-46. SNMOC Analytical Precision:
Coefficient of Variation for all Replicate Analyses, All Sites
Pollutant
Acetylene
Benzene
1,3 -Butadiene
w-Butane
c/5-2-Butene
fra«s-2-Butene
Cyclohexane
Cyclopentane
Cyclopentene
rc-Decane
1-Decene
m -Diethy Ibenzene
p-Diethy Ibenzene
2,2-Dimethylbutane
2,3 -Dimethylbutane
2,3-Dimethylpentane
2,4-Dimethylpentane
w-Dodecane
1-Dodecene
Ethane
Ethy Ibenzene
2-Ethyl-l-butene
Ethylene
OT-Ethyltoluene
o-Ethyltoluene
p-Ethyltoluene
w-Heptane
1-Heptene
w-Hexane
1-Hexene
c/5-2-Hexene
trans-2-Hexene
Isobutane
Isobutene/ 1 -Butene
Isopentane
Isoprene
Isopropy Ibenzene
Isopentane
Isoprene
Isopropy Ibenzene
2-Methyl- 1 -butene
2-Methyl-2-butene
Average
3.55
4.34
9.24
2.86
8.53
8.74
7.47
8.12
17.90
9.76
21.63
17.87
24.25
7.45
6.02
5.79
8.45
24.25
26.19
6.76
9.48
NA
8.38
7.53
9.83
11.00
5.69
12.07
4.49
10.12
29.62
31.71
1.26
3.04
2.11
6.79
17.86
8.16
13.85
44.23
6.60
5.17
Bountiful, UT
(BTUT)
6.03
4.06
4.20
0.59
6.26
12.88
3.87
4.25
45.39
9.14
21.63
10.99
22.29
6.47
4.45
3.34
7.12
20.97
25.87
18.92
6.41
NA
13.13
6.51
11.12
9.01
4.25
8.93
3.11
11.83
56.98
NA
0.34
2.73
0.63
8.93
11.66
8.44
8.47
NA
4.67
3.47
Custer, SD
(CUSD)
1.26
3.78
6.29
1.01
3.98
6.06
7.86
14.55
8.32
14.35
NA
16.02
26.32
8.80
4.90
9.13
10.09
18.64
11.69
9.60
14.41
NA
12.39
5.48
4.46
8.57
5.42
15.81
5.33
8.99
2.26
23.35
0.99
2.65
3.80
4.41
7.16
9.24
12.44
NA
7.53
7.76
Gulfport, MS
(GPMS)
1.79
3.76
11.80
3.02
10.03
6.30
10.17
10.61
8.32
5.73
NA
4.56
35.23
6.91
5.79
8.09
12.09
12.12
43.97
0.57
7.70
NA
1.73
6.83
11.71
9.53
3.60
15.08
3.01
14.34
NA
40.08
1.37
2.29
2.35
4.91
36.90
7.10
14.87
NA
8.10
6.50
Northbrook, IL
(NBIL)
2.42
6.50
8.77
5.63
10.27
12.02
6.52
5.59
18.03
9.71
NA
22.74
24.09
8.70
9.90
4.72
5.13
20.09
23.21
1.11
7.56
NA
2.34
11.33
13.68
14.48
9.31
16.99
5.86
7.09
NA
NA
1.83
3.77
2.09
6.70
19.08
10.01
22.34
NA
7.57
3.18
0
in
*•
5«
"3
ta ^
gS
o fe
a sa
6.26
3.58
15.14
4.07
12.13
6.46
8.91
5.60
9.44
9.88
NA
35.02
13.34
6.34
5.07
3.66
7.80
49.43
NA
3.61
11.33
NA
12.30
7.51
8.19
13.39
5.89
3.55
5.13
8.37
NA
NA
1.75
3.78
1.66
8.99
14.50
6.03
11.12
44.23
5.14
4.91
32-74
-------
Table 32-46. SNMOC Analytical Precision:
Coefficient of Variation for all Replicate Analyses, All Sites (Continued)
Pollutant
2-Methylheptane
3-Methylheptane
2 -Methy Ihexane
3 -Methy Ihexane
3-Methylpentane
2-Methylpentane
4-Methy 1- 1 -pentene
2-Methyl-l-pentene
w-Nonane
1-Nonene
w-Octane
1-Octene
w-Pentane
1 -Pentene
c/5-2-Pentene
/raws-2-Pentene
a-Pinene
6-Pinene
Propane
w-Propylbenzene
Propylene
Propyne
Styrene
TNMOC (Speciated)
TNMOC (w/unknowns)
Toluene
w-Tridecane
1-Tridecene
1 ,2,3 -Trimethylbenzene
1 ,2,4-Trimethylbenzene
1 ,3 ,5-Trimethylbenzene
2,2,3 -Trimethylpentane
2,2,4-Trimethylpentane
2,3 ,4-Trimethylpentane
w-Undecane
1-Undecene
w-Xylene/^-Xylene
o-Xylene
Average
Average
7.56
9.49
7.71
6.71
4.86
5.47
17.18
11.33
9.28
20.55
5.54
15.58
2.56
8.30
12.14
8.30
7.89
19.43
0.87
13.85
2.88
NA
21.67
3.83
3.32
4.19
43.03
NA
17.87
6.99
11.15
21.96
6.08
7.19
11.99
23.20
6.16
8.57
10.28
Bountiful, UT
(BTUT)
6.44
5.95
10.48
3.48
2.34
2.86
10.58
3.38
9.96
28.68
3.27
10.72
1.74
8.09
8.03
5.90
9.79
20.26
0.51
13.23
1.62
NA
19.70
2.40
2.73
3.48
35.51
NA
12.69
6.49
9.79
11.54
4.31
6.11
12.03
8.63
4.67
5.04
9. 76
Custer, SD
(CUSD)
5.97
7.83
8.30
4.47
2.64
8.94
16.24
3.36
10.76
12.17
6.92
16.60
2.00
12.96
4.03
6.72
6.90
23.93
0.80
8.22
2.11
NA
4.87
1.78
2.60
3.96
17.67
NA
14.15
5.65
18.45
27.25
5.83
6.41
10.10
14.34
5.49
6.82
8.83
Gulfport, MS
(GPMS)
10.65
13.34
9.48
11.51
6.61
5.21
28.56
30.03
7.06
13.86
4.56
21.22
4.38
6.98
19.71
6.67
3.83
31.90
0.71
28.65
1.76
NA
10.20
1.96
4.87
2.48
NA
NA
17.44
12.33
12.05
27.71
6.86
7.83
9.87
NA
3.26
11.69
11.03
Northbrook, IL
(NBIL)
8.07
10.39
7.49
5.32
6.17
2.68
NA
8.52
11.94
20.53
6.97
8.68
2.92
4.66
19.14
11.46
6.25
NA
1.28
5.34
2.99
NA
47.28
10.99
2.85
7.55
75.91
NA
25.88
4.88
6.17
12.90
4.40
5.56
7.87
46.87
7.15
12.64
11.27
Q
!/5
0T
13
*l
§£
£&
6.66
9.95
2.82
8.79
6.55
7.65
13.36
NA
6.66
27.52
6.01
20.69
1.76
8.80
9.79
10.77
12.67
1.61
1.06
13.79
5.90
NA
26.31
2.03
3.57
3.48
NA
NA
19.16
5.59
9.30
30.38
8.99
10.07
20.10
22.95
10.22
6.64
10.49
32-75
-------
32.2.3 Carbonyl Compound Analytical Precision
In Table 32-47, the replicate analyses for duplicate and collocated samples show that
laboratory carbonyl analysis precision is within the control limits of 15 percent CV. The overall
average variability is 1.90 percent. In terms of average concentration difference, the carbonyl
precision ranges from 0.001 ppbv for benzaldehyde, crotonaldehyde, isovaleraldehyde, and
hexaldehyde to 0.01 ppbv for formaldehyde.
Table 32-47. Carbonyl Analytical Precision:
734 Replicate Analyses for all Duplicate and Collocated Samples
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
734
734
726
728
698
0
732
714
317
730
704
711
Average RPD
(%)
0.57
0.77
3.36
2.72
2.82
NA
0.68
4.12
3.33
2.53
4.39
4.20
Average
Concentration
Difference (ppbv)
0.005
0.005
0.001
0.002
0.001
NA
0.01
0.001
0.001
0.002
0.002
0.002
Coefficient of
Variation (%)
0.41
0.55
2.38
1.92
1.99
NA
0.48
2.91
2.35
1.79
3.10
2.97
Table 32-48 shows the results from replicate analyses of all collocated carbonyl samples
taken at DEMI, LDTN, MSTN, NBIL, SPIL, and WETX. The replicate results from collocated
samples show variation for the pollutants ranging from 0.43 percent (acetaldehyde) to
3.10 percent (tolualdehydes). The overall average variability is 1.86 percent.
32-76
-------
Table 32-48. Carbonyl Analytical Precision:
264 Replicate Analyses for all Collocated Samples
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
264
264
256
258
244
0
264
256
116
260
254
254
Average RPD
(%)
0.60
0.64
3.35
2.25
3.78
NA
0.69
4.27
3.42
2.16
4.38
3.46
Average
Concentration
Difference (ppbv)
0.004
0.004
0.001
0.002
0.002
NA
0.01
0.003
0.001
0.002
0.001
0.001
Coefficient of
Variation (%)
0.43
0.45
2.37
1.59
2.68
NA
0.49
3.02
2.42
1.53
3.10
2.44
Table 32-49 shows the results from replicate analyses for all duplicate carbonyl samples.
The replicate results from duplicate samples show variation for the pollutants ranging from
0.40 percent (acetaldehyde) to 3.13 percent (valeraldehyde). The overall average variability is
1.91 percent.
Table 32-49. Carbonyl Analytical Precision:
470 Replicate Analyses for all Duplicate Samples
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Number of
Observations
470
470
470
470
454
0
468
458
201
Average RPD
(%)
0.57
0.81
3.37
2.86
2.53
NA
0.68
4.07
3.30
Average
Concentration
Difference (ppbv)
0.01
0.005
0.001
0.002
0.001
NA
0.01
0.001
0.001
Coefficient of
Variation (%)
0.40
0.57
2.38
2.02
1.79
NA
0.48
2.88
2.34
32-77
-------
Table 32-49. Carbonyl Analytical Precision:
470 Replicate Analyses for all Duplicate Samples (Continued)
Pollutant
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
470
450
457
Average RPD
(%)
2.64
4.39
4.42
Average
Concentration
Difference (ppbv)
0.002
0.002
0.002
Coefficient of
Variation (%)
1.86
3.10
3.13
Tables 32-50 through 32-56 present the precision results from carbonyl replicate analyses
for duplicate and collocated samples atNATTS sites (BTUT, DEMI, GPCO, NBIL, S4MO,
SKFL, and SYFL, respectively). The replicate results from the NATTS duplicate samples show
low-level variability among the sites, ranging from 0.10 percent for acetone at GPCO to
12.79 percent for valeraldehyde at BTUT. The average CV, 1.97 percent, is within the Program
DQO of 15 percent overall CV per site.
Table 32-50. Carbonyl Analytical Precision:
24 Replicate Analyses for Duplicate Samples for Bountiful, UT (BTUT)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
24
24
24
24
20
0
24
24
14
24
22
23
Average RPD
(%)
0.44
0.42
4.62
0.74
2.99
NA
0.60
1.81
2.29
1.86
5.50
18.09
Average
Concentration
Difference (ppbv)
0.01
0.01
0.002
0.001
0.001
NA
0.02
0.001
O.001
0.003
0.003
0.02
Coefficient of Variation
(%)
0.31
0.29
3.26
0.52
2.11
NA
0.43
1.28
1.62
1.31
3.89
12.79
32-78
-------
Table 32-51. Carbonyl Analytical Precision:
110 Replicate Analyses for Collocated Samples for Detroit, MI (DEMI)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
110
110
108
110
104
0
110
108
62
110
108
108
Average RPD
(%)
0.75
0.70
5.77
2.86
5.07
NA
0.91
5.58
6.07
2.49
7.25
5.41
Average
Concentration
Difference (ppbv)
0.01
0.01
0.002
0.004
0.003
NA
0.02
0.003
0.001
0.003
0.002
0.002
Coefficient of
Variation (%)
0.53
0.49
4.08
2.02
3.58
NA
0.64
3.94
4.29
1.76
5.13
3.83
Table 32-52. Carbonyl Analytical Precision:
20 Replicate Analyses for Duplicate Samples for Grand Junction, CO (GPCO)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
20
20
20
20
20
0
20
20
12
20
20
20
Average RPD
(%)
0.48
0.15
2.70
2.23
2.96
NA
0.42
4.51
2.83
2.17
3.24
3.56
Average
Concentration
Difference (ppbv)
0.004
0.002
0.001
0.002
0.001
NA
0.01
0.001
0.001
0.002
0.001
0.001
Coefficient of
Variation (%)
0.34
0.10
1.91
1.58
2.09
NA
0.29
3.19
2.00
1.54
2.29
2.51
32-79
-------
Table 32-53. Carbonyl Analytical Precision:
32 Replicate Analyses for Collocated Samples for Northbrook, IL (NBIL)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
32
32
32
32
32
0
32
32
4
32
32
32
Average RPD
(%)
0.62
0.58
2.15
1.40
3.35
NA
0.49
1.78
NA
1.78
5.31
1.81
Average
Concentration
Difference (ppbv)
0.003
0.003
0.001
0.001
0.001
NA
0.01
0.001
NA
0.001
0.002
0.001
Coefficient of
Variation (%)
0.44
0.41
1.52
0.99
2.37
NA
0.35
1.26
NA
1.26
3.75
1.28
Table 32-54. Carbonyl Analytical Precision:
28 Replicate Analyses for Duplicate Samples for St. Louis, MO (S4MO)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
28
28
28
28
24
0
28
28
16
28
28
28
Average RPD
(%)
0.40
0.42
3.00
2.78
3.82
NA
0.51
4.11
2.13
3.48
6.35
2.79
Average
Concentration
Difference (ppbv)
0.01
0.01
0.001
0.002
0.001
NA
0.01
0.001
0.001
0.003
0.003
0.001
Coefficient of
Variation (%)
0.28
0.30
2.12
1.96
2.70
NA
0.36
2.90
1.51
2.46
4.49
1.97
32-80
-------
Table 32-55. Carbonyl Analytical Precision:
24 Replicate Analyses for Duplicate Samples for Tampa, FL (SKFL)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
24
24
24
24
24
0
24
24
8
24
22
24
Average RPD
(%)
0.48
0.76
2.15
2.49
1.73
NA
0.59
3.32
0.94
3.65
3.85
3.29
Average
Concentration
Difference (ppbv)
0.003
0.002
0.001
0.002
0.001
NA
0.01
0.001
0.001
0.003
0.001
0.001
Coefficient of
Variation (%)
0.34
0.54
1.52
1.76
1.23
NA
0.42
2.35
0.67
2.58
2.72
2.33
Table 32-56. Carbonyl Analytical Precision:
28 Replicate Analyses for Duplicate Samples for Tampa, FL (SYFL)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Number of
Observations
28
28
28
28
28
0
28
28
12
28
28
28
Average RPD
(%)
0.90
1.46
4.12
2.23
2.38
NA
0.84
3.40
4.62
4.01
4.23
3.87
Average
Concentration
Difference (ppbv)
0.005
0.004
0.001
0.002
0.002
NA
0.01
0.001
0.001
0.003
0.001
0.001
Coefficient of
Variation (%)
0.63
1.03
2.91
1.58
1.68
NA
0.59
2.40
3.26
2.84
2.99
2.73
32-81
-------
Table 32-57 presents the average CV per pollutant, per pollutant per site, per site, and the
overall CV. The replicate results from duplicate and collocated samples show low-level
variability among the sites, ranging from 1.36 percent at NBIL to 2.76 percent at DEMI. The
average CV is 1.90 percent, which is well with in the requested 15 percent overall CV per site.
Table 32-57. Carbonyl Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Average
Average
0.41
0.55
2.38
1.92
1.99
NA
0.48
2.91
2.35
1.79
3.10
2.97
1.90
St. Petersburg,
FL (AZFL)
0.59
0.52
3.00
2.47
1.55
NA
0.44
2.93
NA
1.67
2.13
2.40
7.77
Barceloneta,
PR (BAPR)
0.43
0.94
2.30
2.98
2.63
NA
1.07
3.21
NA
3.04
4.34
3.11
2.40
Bountiful, UT
(BTUT)
0.31
0.29
3.26
0.52
2.11
NA
0.43
1.28
1.62
1.31
3.89
12.79
2.53
^
f-.
ig
i|
u B
0.62
1.50
0.60
3.15
1.34
NA
0.83
2.74
3.56
1.86
6.24
3.85
2.39
*TI
*$s
Ja
SB
0.46
0.39
3.44
1.76
1.82
NA
0.45
3.05
3.18
1.50
3.10
2.74
1.99
Custer, SD
(CUSD)
0.36
0.29
2.71
1.20
2.09
NA
0.67
3.65
2.22
1.28
3.32
2.31
1.83
Detroit, MI
(DEMI)
0.53
0.49
4.08
2.02
3.58
NA
0.64
3.94
4.29
1.76
5.13
3.83
2.76
Table 32-57. Carbonyl Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site (Continued)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Average
0.41
0.55
2.38
1.92
Z
ji
1 1
0.27
0.36
3.32
1.27
-J
11
0.10
0.69
2.18
2.24
J
||
0.47
0.69
3.02
1.83
=
lo
lo
O U
0.34
0.10
1.91
1.58
•V
H
31
0.47
0.70
2.21
2.33
H
•V
o
Id
0.36
0.27
2.33
2.26
Z
H
•V
Z ^
0.24
0.35
3.20
1.95
32-82
-------
Table 32-57. Carbonyl Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site (Continued)
Pollutant
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Average
Average
1.99
NA
0.48
2.91
2.35
1.79
3.10
2.97
1.90
Z
•N
•Q f^
"i Z
2 &
2.67
NA
0.33
3.28
3.65
2.52
3.87
2.07
2. 15
j
•Jfe
0 &
1.76
NA
0.36
2.93
3.20
1.53
2.38
2.04
7.77
-J
•v /— S
g-E
s *t,
1.49
NA
0.30
3.03
2.62
1.39
2.02
2.11
7.72
•V
lo
^ &H
•a u
o 8
2.09
NA
0.29
3.19
2.00
1.54
2.29
2.51
1.62
in
t ^
J-g
5 ^
1.80
NA
0.92
3.10
2.02
2.04
3.43
3.39
2.04
Z
H
—
1 ft
z d
2.97
NA
0.57
2.95
0.42
0.99
2.46
1.61
1.56
Z
H
3 iz
"S CA)
c« 3
Z S
2.70
NA
0.44
2.50
3.60
1.55
2.64
2.54
1.97
Table 32-57. Carbonyl Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site (Continued)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Average
Average
0.41
0.55
2.38
1.92
1.99
NA
0.48
2.91
2.35
1.79
3.10
2.97
1.90
Northbrook, IL
(NBIL)
0.44
0.41
1.52
0.99
2.37
NA
0.35
1.26
NA
1.26
3.75
1.28
1.36
New Brunswick,
NJ (NBNJ)
0.34
0.52
1.40
2.22
0.97
NA
0.31
1.94
NA
1.74
3.01
3.80
1.63
Orlando, FL
(ORFL)
0.30
0.37
2.62
1.60
1.04
NA
0.34
2.66
NA
1.09
1.60
2.86
1.45
O
S
•V
%
'3 o"
3i
*i
0.28
0.30
2.12
1.96
2.70
NA
0.36
2.90
1.51
2.46
4.49
1.97
1.91
0
!/5
•V
%
"3
ta K
%%
o ta
££
0.32
0.33
2.53
1.06
2.90
NA
0.39
3.16
NA
1.03
3.35
2.29
1.74
&
a.
•V
CS _
Z®
§^
<% s
0.19
0.84
1.57
2.87
1.08
NA
0.31
3.93
1.44
1.46
2.90
3.75
1.85
J
u.
g,J
S Njj
H S
0.34
0.54
1.52
1.76
1.23
NA
0.42
2.35
0.67
2.58
2.72
2.33
1.50
32-83
-------
Table 32-57. Carbonyl Analytical Precision:
Coefficient of Variation for all Replicate Analyses by Site (Continued)
Pollutant
Acetaldehyde
Acetone
Benzaldehyde
Butyraldehyde
Crotonaldehyde
2,5-Dimethylbenzaldehyde
Formaldehyde
Hexaldehyde
Isovaleraldehyde
Propionaldehyde
Tolualdehydes
Valeraldehyde
Average
Average
0.41
0.55
2.38
1.92
1.99
NA
0.48
2.91
2.35
1.79
3.10
2.97
1.90
Tampa, FL
(SMFL)
0.97
0.73
2.37
2.88
0.89
NA
0.38
3.56
1.75
1.51
2.27
2.59
1.81
Schiller Park,
IL (SPIL)
0.38
0.55
1.41
0.77
2.61
NA
0.20
5.03
NA
1.82
2.37
3.07
1.82
-J
to
1-
Js
0.63
1.03
2.91
1.58
1.68
NA
0.59
2.40
3.26
2.84
2.99
2.73
2.06
!/5
s
0&
•is
O.L3
£E
0.21
0.32
2.62
3.17
1.93
NA
0.41
2.35
NA
2.88
1.74
0.85
1.65
X
H ^
.5$
•s w
3t
0.59
0.63
1.67
1.54
1.82
NA
0.72
2.42
1.35
1.77
2.23
2.34
1.55
32.2.4 Hexavalent Chromium Analytical Precision
Table 32-58 presents the hexavalent chromium analytical precision data. The duplicate
hexavalent chromium samples for the WETX site were not analyzed in replicate, therefore is not
included. The range of variability for hexavalent chromium is 1.00 percent (CHSC) to
11.70 percent (WADC), with the overall average variation of 4.4 percent.
Table 32-58. Hexavalent Chromium Analytical Precision:
Replicate Analyses for Collocated Samples
Site
BTUT
BOMA
CHSC
DEMI
GPCO
HAKY
Number of
Observations
70
8
8*
30
8
8*
Average
RPD
(%)
0.22
10.34
1.41
1.94
3.52
1.39
Average
Concentration
Difference
(ng/m3)
0.001
0.004
0.001
0.004
0.002
0.002
Coefficient
of Variation
(%)
4.00
7.30
1.00
5.30
3.60
9.30
32-84
-------
Table 32-58. Hexavalent Chromium Analytical Precision:
Replicate Analyses for Collocated Samples (Continued)
Site
MVWI
NBIL
PRRI
PXSS
S4MO
SDGA
SYFL
UNVT
WADC
Average
Number of
Observations
8*
62
8*
12
8
8
12*
12*
8*
26
Average
RPD
(%)
NA
0.02
0.14
0.14
3.74
2.32
0.60
NA
16.51
3.25
Average
Concentration
Difference
(ng/m3)
NA
0.002
NA
0.01
0.002
0.001
0.001
NA
0.002
0.002
Coefficient
of Variation
(%)
NA
2.80
1.20
4.50
2.60
1.60
2.90
NA
11.70
4.40
* Over half of the detects were under the detection limit.
32.3 Bias
Laboratories typically evaluate their bias (or accuracy) by analyzing external audit
samples and comparing the measured concentrations obtained to the known concentrations of
those audit samples. Bias, or accuracy, indicates the extent to which experimental measurements
represent their corresponding "true" or "actual" values.
The accuracy of the 2006 monitoring data can also be assessed qualitatively by reviewing
the accuracy of the monitoring methods and how they were implemented:
• The sampling and analytical methods used in the 2006 monitoring effort have
been approved by EPA for accurately measuring ambient levels of various
compounds—an approval that is based on many years of research into the
development of ambient air monitoring methodologies.
• When collecting and analyzing ambient air samples, all field sampling staff and
laboratory analysts strictly followed quality control and quality assurance
guidelines detailed in the respective monitoring methods. This strict adherence to
the well-documented sampling and analytical methods suggests, though certainly
does not prove, that the 2006 monitoring data accurately represent ambient air
quality.
32-85
-------
32.3.1 Proficiency Test Studies
Laboratories participating in NATTS are provided with proficiency test (PT) audit
samples on a quarterly basis for VOC, carbonyls, and metals. These PT samples can be used as a
measure of analytical accuracy.
Tables 32-59 through 32-61 present ERG's results from the 2006 NATTS PT audit
samples for carbonyls, metals, and VOC, respectively. The acceptable percent difference from
the true values is ± 25 percent, and the values exceeding this criteria are bolded in the tables.
While there are a few values outside the Program DQOs, there are no compounds that are
consistently over for multiple audits.
Table 32-59. Carbonyl NATTS PT Audit Samples - Percent Difference from True Value
Pollutant
Acetaldehyde
Crotonaldehyde
Formaldehyde
June, 2006
0.8
-31.0
-9.7
October, 2006
-2.5
-28.0
-16.8
Table 32-60. Metals NATTS PT Audit Samples - Percent Difference from True Value
Pollutant
Arsenic
Beryllium
Cadmium
Lead
Manganese
Nickel
April, 2006
17.3
15.5
19.9
13.0
20.8
14.8
July, 2006
10.8
16.0
3.8
5.5
-10.0
-3.0
September, 2006
2.3
1.4
-1.9
-6.6
-9.5
-8.2
November, 2006
25.1
23.6
17.4
4.5
-0.5
1.1
Table 32-61. VOC NATTS PT Audit Samples - Percent Difference from True Value
Pollutant
Acrolein
Benzene
1,3 -Butadiene
Carbon Tetrachloride
Chloroform
1 ,2-Dibromoethane
May, 2006
Not included
-14.1
8.5
-4.0
14.6
7.6
August, 2006
Not included
-1.4
3.9
-18.8
0.0
22.5
October, 2006
-36.5
-5.0
3.9
4.3
-2.1
4.6
December, 2006
-27.2
-31.2
7.3
-1.7
3.2
-18.5
32-86
-------
Table 32-61. VOC NATTS PT Audit Samples - Percent Difference from True Value
(Continued)
Pollutant
1 ,2-Dichloroethane
Dichloromethane
1 ,2-Dichloropropane
cis- 1 , 3 -Dichloropropene
trans- 1 ,3 -Dichloropropene
1 , 1 ,2,2-Tetrachloroethane
retrachloroethylene
rrichloroethylene
Vinyl Chloride
May, 2006
27.1
14.1
-12.8
3.5
1.4
-5.6
-13.3
13.9
-5.1
August, 2006
9.8
10.5
-1.4
13.3
17.9
11.4
-9.7
50.6
-11.4
October, 2006
5.1
8.5
-3.2
-0.6
1.2
-2.9
-12.6
10.1
-18.5
December, 2006
-10.7
8.0
-8.2
-35.6
-39.3
-20.5
-21.4
-8.1
-9.2
32-87
-------
33.0 Conclusions and Recommendations
As presented in this report, UATMP monitoring data offer a wealth of information for
evaluating trends, patterns, and the potential for health risk in air quality and should ultimately
help a wide range of audiences understand the complex nature of urban and rural air pollution.
The following discussion summarizes the primary conclusions drawn from this report and
presents recommendations for ongoing urban air monitoring efforts.
33.1 Conclusions
Characterization of the 2006 UATMP monitoring data identified the following notable
trends and patterns in national-level and state-level urban air pollution:
33.1.1 National-Level Conclusions
• Ambient air concentration data sets. Generally, the data met the quality objectives
for completeness. The target for completeness was 85-100 percent. Sixteen of 139
data sets failed to comply with the data quality objective of 85 percent completeness.
Forty-nine data sets achieved 100 percent completeness.
• NATTS sites. Eighteen of the 59 sites are EPA-designated NATTS sites (BOMA,
BTUT, CHSC, DEMI, GPCO, HAKY, LAOR, MVWI, NBIL, PRRI, PXSS, S4MO,
SDGA, SEW A, SKFL, SYFL, UNVT, and WADC).
• Number of samples for UATMP pollutants. 182,974 valid measurements of urban air
toxics were made.
• Ambient air concentrations of urban air toxics. Approximately 78 percent of the
measured concentrations were less than 1 //g/m3. Less than 3 percent of the
concentrations were greater than 5 //g/m3.
• Measured Detections. Ninety-one pollutants were not detected at any of the
participating sites. However, if SVOC analysis measured with SW-846 Method 8270
are excluded, nine pollutants (bromochloromethane; 1,1-dichloroethane; c/s-1,3-
dichloropropene; rram'-l,3-dichloropropene; 2,5-dimethylbenzaldehyde; 1-decene; 2-
ethyl-1-butene; 1-tridecene; and propyne) were not detected at any of the participating
sites.
• Nationwide Pollutants of Interest. The pollutants of interest at the national level,
based on the number of exceedances, or "failures", of the preliminary risk screening
values, included: acetaldehyde, acrolein, arsenic, benzene, 1,3-butadiene, carbon
tetrachloride,/?-dichlorobenzene, formaldehyde, hexachloro-l,3-butadiene,
hexavalent chromium, manganese, naphthalene, and tetrachloroethylene. The
pollutants of interest varied for the individual sites.
33-1
-------
• Short-term Risk. Three pollutants of interest (acrolein, benzene, and formaldehyde)
had daily measurements that exceeded one or both of the short-term risk factors.
Acrolein exceeded the ATSDR short-term MRL and the CALEPA REL at thirty-three
sites; benzene exceeded the ATSDR short-term MRL at SIAL; and formaldehyde
exceeded the ATSDR short-term MRL at INDEM, NBIL, and SPIL (all within the
Chicago MSA).
• Chronic Cancer Risk. The cancer risk calculated for SIAL for benzene (48 in-a-
million) was the highest of all annual average-based cancer risks. By comparison,
NATA-modeled cancer risk was highest for arsenic at ININ (208 in-a-million),
dichloromethane at BAPR (71 in-a-million), and benzene at MIMN (39 in-a-million),
based on the NATA.
• Chronic Noncancer Risk. Five sites exhibited acrolein HQs based on annual averages
greater than 100, each in the Austin, Texas area. Twenty-eight other sites had
acrolein HQs that were greater than 1.0. In addition, manganese had HQs greater
than 1.0 for the three Birmingham, Alabama sites, and formaldehyde's HQs were
greater than 1.0 for SPIL and INDEM. Noncancer risk (HQ) based on NATA was
highest for acrolein for ELNJ (35.46), and only acrolein had modeled HQ values
greater than 1.0.
• Pearson Correlations. Pearson Correlations between each pollutant of interest and
various meteorological parameters were computed for each site. Generally, the
meteorological parameters had poor correlations with the nationwide pollutants of
interest across all the sites. The Pearson Correlations were much stronger at the
individual sites.
• Automobile Impacts. Maricopa County, AZ had the highest vehicle registration,
while Jefferson County, AL had the highest hydrocarbon average concentration of all
the UATMP counties. The Schiller Park site (SPIL) near Chicago had the highest
daily traffic passing by the monitor (214,900), and Cook County, IL, the county
where SPIL is located, also had the highest nonroad emissions of all the participating
sites; Wayne County, MI, the county where DEMI is located, had the highest on-road
emissions of all the sites. The Cherokee Nation site (CNEP) in Pryor, Oklahoma had
the lowest daily traffic volume (5).
• Emissions and Toxicity Weighted Emissions. Benzene is the pollutant (with a cancer
risk factor) that had the highest county-level emissions for most UATMP counties.
This pollutant also had the highest toxicity-weighted emissions. Acrolein had the
highest toxicity-weighted emissions of pollutants with noncancer risk factors,
although it was not emitted in high enough quantities to rank in the top 10 for any
UATMP county.
33-2
-------
33.1.2 Supplementary Observations and Interpretations
• Acetaldehyde and formaldehyde were the two most common pollutants of interest for
the UATMP sites. All sites that sampled carbonyls had acetaldehyde and
formaldehyde as pollutants of interest. Benzene and carbon tetrachloride were the
two most common VOC pollutants of interest. Every site that sampled VOC had
these two pollutants as pollutants of interest.
• Formaldehyde frequently had the highest daily average for the UATMP sites; this
pollutant had the highest daily average for twenty-eight sites. Xylenes followed with
seven sites.
• Pearson correlations calculated between formaldehyde and the temperature
parameters (maximum and average temperature) for many UATMP sites were at least
moderately strong and positive. This indicates that as temperatures increase,
concentrations of formaldehyde also increase. At some of these same sites, the
summer formaldehyde average tended to be higher than other seasons, supporting this
observation.
• Pearson correlations calculated between most of the pollutants of interest and the
scalar wind speed at most UATMP sites tended to be negative. This indicates that as
wind speed decreases, concentrations of the pollutants of interest increase.
• Pearson correlations calculated between hexachloro-1,3-butadiene and the
meteorological parameters for many UATMP appear to be strong. It must be noted
that this compound was detected fairly infrequently at most sites, and that this low
number of measured detections may skew the correlations into appearing stronger
than they might be with a large measurement population.
• Carbon tetrachloride often had relatively high cancer risks based on annual averages
for the UATMP sites, but tended to have relatively low emissions and toxicity-
weighted emissions according to the NEI emissions inventory. This suggests that this
pollutant is present in "background" levels of ambient air; that is, it is consistently
present at similar levels at any given location. Although production of this pollutant
has declined sharply over the last thirty years due to its role as an ozone depleting
substance, it has a relatively long atmospheric lifetime.
• Acrolein emissions and mass concentrations are relatively low when compared to
other pollutants. However, due to the high toxicity of this pollutant, low mass
concentrations translated into very high noncancer risks. This trend was also evident
when the acrolein emissions were toxicity-weighted; the toxicity-weighted value was
often several orders of magnitude higher than other pollutants. Acrolein was also a
national noncancer risk driver according to NATA.
33-3
-------
33.1.3 State-Level Conclusions
• Alabama.
The Alabama sites began sampling in mid-July 2005 and continued through June
2006. They sampled for VOC, carbonyl compounds, SVOC, and metals (TSP at
all four sites, PMio at NBAL). In order to facilitate analysis, data from the entire
year's worth of sampling were utilized in the site-specific analyses.
The pollutants of interest common to each Alabama site were: acrolein, arsenic,
formaldehyde, carbon tetrachloride, manganese, acetaldehyde, benzene,
naphthalene, hexachloro-1,3-butadiene, and/>-dichlorobenzene.
Of the pollutants of interest for each site, total xylenes had the highest daily
average for ETAL and NBAL, while formaldehyde had the highest daily average
for PVAL, and benzene was highest for SIAL.
Acrolein exceeded the short-term risk factors at all of the Alabama sites each time
it was measured. One benzene concentration exceeded the short-term risk factor
at SIAL. Where seasonal averages could be calculated for acrolein, they
exceeded the intermediate risk factors. None of the seasonal averages of benzene
for SIAL exceeded the intermediate risk factor.
Most of the pollutants of interest, especially formaldehyde, exhibited positive
correlations with maximum, average, dew point, and wet bulb temperatures across
the Alabama sites. Negative correlations were consistently calculated between
most of the pollutants of interest and scalar wind speed.
As illustrated by the composite 24-hour back trajectory maps, the back trajectories
originated from a variety of directions at the Alabama sites. The airshed domains
were comparable in size to other UATMP sites, as the farthest away back
trajectories originated was 600 miles.
The wind roses for the Birmingham sites show that calm winds were observed for
about 1/3 of observations, and that northerly, south-southeasterly, and southerly
winds were predominant near the Birmingham sites. The PVAL site's wind rose
shows that while calm winds were also observed 1/3 of the time, southerly,
westerly, and west-northwesterly winds were most common.
Benzene had the highest annual average-based cancer risks for ETAL, NBAL,
and SIAL, while hexachloro-1,3-butadiene had the highest annual average-based
cancer risk for PVAL. By comparison, benzene, 1,3-butadiene, and acetaldehyde
had the highest NATA-modeled cancer risk for the three Birmingham census
tracts, while benzene, carbon tetrachloride, and acetaldehyde had the highest
NATA-modeled cancer risk for the PVAL census tract.
33-4
-------
> Acrolein exhibited the highest annual average-based and NATA-modeled
noncancer risks for each of the Alabama sites.
> Benzene was the highest emitted pollutant with a cancer risk factor in Jefferson
County, Alabama, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
emissions, while acrolein had the highest noncancer toxicity weighted-emissions
in Jefferson County.
Arizona.
> The PXSS site sampled for metals (PMio) and hexavalent chromium.
> The pollutants of interest for PXSS were: manganese, arsenic, and hexavalent
chromium.
*• Of the pollutants of interest, manganese had the highest daily average for PXSS,
and was two orders of magnitude higher than the daily averages of the other
pollutants of interest.
*• No concentrations exceeded the short-term risk factors at PXSS.
> Correlations between the pollutants of interest for PXSS and the meteorological
parameters were mostly weak.
> As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at PXSS. The airshed domain was
somewhat smaller in size compared to other UATMP sites, as the farthest away a
back trajectory originated was just over 500 miles.
> The wind rose shows that winds were predominantly from the east near PXSS.
*• Arsenic had the highest annual average-based cancer risk for PXSS. In
comparison, hexavalent chromium had the highest NATA-modeled cancer risk for
the census tract where PXSS is located. The NATA-modeled cancer risks for the
pollutants that failed at least one screen at PXSS tended to be at least an order of
magnitude lower than those based on the annual averages.
> Manganese exhibited the highest annual average-based noncancer risk for PXSS.
Although none of the annual average-based noncancer risks were greater than 1,
they tended to be at least an order of magnitude higher than the NATA-modeled
noncancer risks.
*• Benzene was the highest emitted pollutant with a cancer risk factor in Maricopa
County, Arizona, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
33-5
-------
emissions, while acrolein had the highest noncancer toxicity weighted-emissions
in Maricopa County.
Colorado.
> The GPCO site sampled for VOC and carbonyl compounds.
*• The pollutants of interest for GPCO were: formaldehyde, acetaldehyde, benzene,
carbon tetrachloride, 1,3-butadiene, acrolein, tetrachloroethylene, and
p-di chl orob enzene.
*• Of the pollutants of interest, formaldehyde had the highest daily average for
GPCO, followed by acetaldehyde and benzene. Formaldehyde was highest in
summer; carbon tetrachloride was highest in summer and autumn; and benzene
and 1,3-butadiene were highest in autumn and winter.
*• Every acrolein concentration exceeded the short-term risk factors for GPCO, and
every seasonal average of acrolein exceeded the intermediate-term risk factor.
*• Correlations between the pollutants of interest for GPCO and the temperature
parameters support the trends shown by the seasonal averages. Additionally, all
of the correlations with wind speed were negative.
*• As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at GPCO, although less frequently from the
northeast, east, and southeast. The airshed domain was somewhat smaller in size
compared to other UATMP sites, as the farthest away a back trajectory originated
is less than 500 miles.
> The wind rose shows that easterly and southeasterly winds were most frequently
observed near GPCO.
*• A trends analysis shows that formaldehyde may be increasing at GPCO. Outliers
measured in the 2004 make the identification of a long-term trend difficult.
*• Benzene had the highest annual average-based and NATA-modeled cancer risk
for GPCO, although the risk based on the annual average was an order of
magnitude higher.
*• Acrolein had the highest annual average-based and NATA-modeled noncancer
risk for GPCO, although the risk based on the annual average was an order of
magnitude higher.
*• Benzene was the highest emitted pollutant with a cancer risk factor in Mesa
County, Colorado, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
33-6
-------
emissions, while acrolein had the highest noncancer toxicity weighted-emissions
in Mesa County.
District of Columbia.
> The WADC site sampled for hexavalent chromium only, and therefore hexavalent
chromium was this site's only pollutant of interest. Hexavalent chromium failed
one screen at WADC.
> The summer average concentration of hexavalent chromium was significantly
higher than the other seasonal averages, but the high confidence interval suggests
that the summer average was influenced by outliers. The highest concentration of
hexavalent chromium at WADC was measured on July 4, 2006.
> Hexavalent chromium does not have acute risk factors. While an intermediate-
term risk factor is available, it was not exceeded at WADC.
> Correlations between hexavalent chromium for WADC and the meteorological
parameters tended to be weak.
*• As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at WADC, although less frequently from
the east. The airshed domain was comparable in size to other UATMP sites, as
the farthest away a back trajectory originated is greater than 600 miles.
> The wind rose shows that southerly winds were most frequently observed near
WADC.
*• The annual average-based and NATA-modeled cancer and noncancer risks
attributable to hexavalent chromium for WADC were very similar.
*• Benzene was the highest emitted pollutant with a cancer risk factor in the District
of Columbia, while toluene was the highest emitted pollutant with a noncancer
risk factor. Benzene also had the highest cancer toxicity weighted-emissions,
while acrolein had the highest noncancer toxicity weighted-emissions.
Florida.
> The seven Florida sites sampled for carbonyl compounds. In addition, SYFL also
sampled hexavalent chromium.
> Two carbonyl compounds have risk screening values, formaldehyde and
acetaldehyde. These pollutants failed screens at every Florida site and were the
pollutants of interest for each site.
33-7
-------
Formaldehyde tended to have the highest daily average for each of the Florida
sites, although the difference was not statistically significant for all sites.
No concentrations of acetaldehyde or formaldehyde exceeded the short-term risk
factors at the Florida sites.
Acetaldehyde exhibited negative correlations with the moisture variables for the
Florida sites, and formaldehyde exhibited mostly positive correlations with the
temperature parameters for the Florida sites.
As illustrated by the composite 24-hour back trajectory maps, the back trajectories
originated from a variety of directions at the Florida sites. The airshed domains
were comparable in size to other UATMP sites, as the farthest away back
trajectories originated is nearly 600 miles.
Similar to the back trajectories, the wind roses show that winds from a variety of
directions were observed near the Florida sites.
A trends analysis was conducted for AZFL, GAFL, ORFL, SKFL, and SYFL.
Formaldehyde seems to be increasing at AZFL and GAFL, decreasing at ORFL,
and is difficult to assess at SKFL and SYFL due to large confidence intervals in
years prior to 2006.
Annual average-based and NATA-modeled cancer risks for acetaldehyde and
formaldehyde for the Florida sites were very similar, although no cancer risks
based on annual average were available for FLFL.
Annual average-based and NATA-modeled noncancer risks for acetaldehyde and
formaldehyde for the Florida sites were very similar, and were all less than 1.0.
Again, a noncancer risk based on the annual average was not available for FLFL.
Benzene was the highest emitted pollutant with a cancer risk factor in the counties
with UATMP monitoring sites. Benzene also had the highest cancer toxicity
weighted-emissions in Hillsborough, Orange, and Pinellas Counties, while
naphthalene had the highest cancer toxicity weighted-emissions in Broward
County.
Xylenes were the highest emitted pollutant with a noncancer risk factor in
Broward County; hydrochloric acid was the highest emitted pollutant with a
noncancer risk factor in Hillsborough County; and toluene was the highest
emitted pollutant with a noncancer risk factor in Orange and Pinellas Counties.
Yet, acrolein had the highest noncancer toxicity weighted-emissions.
33-8
-------
Georgia.
The SDGA site sampled for hexavalent chromium only, and was therefore this
site's only pollutant of interest. Hexavalent chromium failed five screens at
SDGA.
The concentration of hexavalent chromium was highest in the summer and lowest
in winter, although the difference was not statistically significant.
Hexavalent chromium does not have acute risk factors. While an intermediate-
term risk factor is available, it was not exceeded at SDGA.
Correlations between hexavalent chromium for SDGA and the meteorological
parameters tended to be weak.
As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at SDGA. The airshed domain was
comparable in size to other UATMP sites, as the farthest away a back trajectory
originated is greater than 600 miles.
The wind rose shows that northwesterly winds were most frequently observed
near SDGA.
The annual average-based and NATA-modeled cancer and noncancer risks
attributable to hexavalent chromium for SDGA were very similar.
Benzene was the highest emitted pollutant with a cancer risk factor in De Kalb
County, Georgia, while methyl isobutyl ketone was the highest emitted pollutant
with a noncancer risk factor. Benzene also had the highest cancer toxicity
weighted-emissions, while acrolein had the highest noncancer toxicity weighted-
emissions.
Illinois.
NBIL sampled for carbonyl compounds, VOC, SNMOC, hexavalent chromium,
and metals (PMio), while SPIL sampled for carbonyls and VOC only.
The pollutants of interest common to each Illinois site were: acrolein,
formaldehyde, carbon tetrachloride, tetrachloroethylene, acetaldehyde, benzene,
trichloroethylene, 1,3 -butadiene, and/>-dichlorobenzene.
Of the pollutants of interest for each site, formaldehyde had the highest daily
average for both sites. The daily average concentration was significantly higher
for SPIL than for NBIL. The high confidence interval for NBIL indicates that this
average was driven by outliers. The relatively large formaldehyde concentration
for winter and the corresponding confidence interval show that the outlier(s) were
33-9
-------
measured during winter. For SPIL, formaldehyde was highest in summer and
spring, but like NBIL's winter average, the large confidence intervals show that
outliers were affecting these averages.
Acrolein and formaldehyde exceeded the short-term risk factors at the Illinois
sites. While nearly all of the acrolein measured detections exceeded the short-
term risk factors, a total of five formaldehyde concentrations exceeded the short-
term risk factors at NBIL and SPIL. Where seasonal averages could be calculated
for acrolein, they exceeded the intermediate risk factors. None of the seasonal
averages of formaldehyde exceeded the intermediate risk factor.
Correlations between formaldehyde for SPIL and the temperature parameters
were the strongest calculated for these sites, and support the trends shown by the
seasonal formaldehyde averages for this site. Correlations with wind speed were
nearly all negative.
As illustrated by the composite 24-hour back trajectory maps, the back trajectories
originated from a variety of directions at the Illinois sites. The airshed domains
were larger in size than other UATMP sites, as some back trajectories originated
over 800 miles away.
While winds from a variety of directions were observed near the Illinois sites,
westerly and southerly winds were observed more frequently.
A trends analysis was conducted for the Illinois sites, although carbonyl sampling
has not been performed long enough for a trends analysis. Benzene and 1,3-
butadiene have been decreasing at NBIL and appear to be holding steady at SPIL.
Carbon tetrachloride and benzene had the highest annual average-based cancer
risks for both NBIL and SPIL. By comparison, benzene and 1,3-butadiene had
the highest NATA-modeled cancer risks for the Chicago census tracts.
Acrolein exhibited the highest annual average-based and NATA-modeled
noncancer risks for the Illinois sites. For SPIL, formaldehyde also had a
noncancer risk based on the annual average greater than 1.0.
Benzene was the highest emitted pollutant with a cancer risk factor in Cook
County, Illinois, while toluene was the highest emitted pollutant with a noncancer
risk factor. Benzene also had the highest cancer toxicity weighted-emissions,
while acrolein had the highest noncancer toxicity weighted-emissions in Cook
County.
Indiana.
IDIN sampled for carbonyl compounds, hexavalent chromium, and metals
(PMio); ININ sampled for carbonyl compounds and metals (PMio); and WPIN
and INDEM sampled for carbonyls only.
33-10
-------
The pollutants of interest common to each Indiana site were formaldehyde and
acetaldehyde.
Formaldehyde had the highest daily average for all four sites, but was particularly
high for INDEM. The INDEM average was higher than any other daily average
concentration for a UATMP site, which is consistent with findings from 2005.
Seasonal averages of formaldehyde for INDEM indicate that while relatively high
concentrations of formaldehyde were recorded throughout the year, the highest
measurements occurred during spring and summer.
Formaldehyde exceeded the short-term risk factors at INDEM. Nearly half of the
measured concentrations of formaldehyde exceeded the ATSDRMRL, and half
of those concentrations also exceeded the CALEPA REL. Three of the four
seasonal averages of formaldehyde exceeded the intermediate-term MRL.
Many of the pollutants of interest exhibited moderately strong to very strong
correlations with the meteorological parameters for the Indiana monitoring sites.
But the number of detects must be considered because a low number of detects
can skew the correlations.
As illustrated by the composite 24-hour back trajectory maps for the Indianapolis
sites, the back trajectories originated primarily from the south-southeast and
northwest. However, a complete sampling year of trajectories is necessary for a
more accurate assessment. Back trajectories originated from a variety of
directions around the INDEM site. The airshed domain was larger in size than
other UATMP sites, as some back trajectories originated over 800 miles away.
The wind roses for the Indiana sites do not resemble each other. Winds from a
variety of directions were frequently measured near IDIN and ININ, although less
frequently from the northeast; near INDEM, calm, southerly, and westerly winds
were frequently observed; and near WPIN, southwesterly and westerly winds
were most common.
A trends analysis was conducted for the INDEM site for formaldehyde.
Formaldehyde concentrations have been relatively high at INDEM since the onset
of UATMP sampling, but the large confidence intervals indicate that little
significant change has occurred.
Annual averages, and hence cancer and noncancer risks, could be calculated for
INDEM only. Although the annual average was high for formaldehyde, the
cancer risk was low because formaldehyde has a low cancer toxicity. However,
formaldehyde has a high noncancer toxicity, and this is reflected in its noncancer
risk. The NATA-modeled concentration and risks for formaldehyde did not
reflect the concentration and theoretical risks resulting from the ambient
monitoring. The NATA-modeled cancer risk for arsenic near ININ was the
33-11
-------
highest cancer risk for any of the site-specific pollutants of interest. The NATA-
modeled cancer risk for arsenic near IDIN was significantly lower.
Benzene was the highest emitted pollutant with a cancer risk factor in both
Marion and Lake Counties, while coke oven emissions had the highest cancer
toxicity weighted-emissions in these counties. Toluene was the highest emitted
pollutant with a noncancer toxicity factor in Marion County, while hydrochloric
acid was the highest emitted pollutant with a noncancer toxicity factor in Lake
County. Like most UATMP counties, acrolein had the highest noncancer toxicity
weighted-emissions in Marion County, but the second highest noncancer toxicity
weighted-emissions in Lake County. Manganese had the highest noncancer
toxicity weighted-emissions in Lake County.
Kentucky.
The HAKY site sampled for hexavalent chromium only. Although this pollutant
did not fail any screens, it was still considered this site's pollutant of interest in
order to facilitate analysis.
The concentration of hexavalent chromium was highest in the summer and lowest
in winter, although the difference was not statistically significant.
Hexavalent chromium does not have acute risk factors. While an intermediate-
term risk factor is available, it was not exceeded for HAKY.
Correlations between hexavalent chromium for HAKY and the temperature and
moisture variables were moderately strong and positive.
As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at HAKY. The airshed domain was
comparable in size to other UATMP sites, as the farthest away a back trajectory
originated was greater than 600 miles.
The wind rose shows that calm winds prevailed and that winds with an easterly
component were rarely observed near HAKY.
The annual average-based and NATA-modeled cancer and noncancer risks
attributable to hexavalent chromium for HAKY were low.
Benzene was the highest emitted pollutant with a cancer risk factor in Hazard
County, Kentucky, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
emissions, while acrolein had the highest noncancer toxicity weighted-emissions.
33-12
-------
Massachusetts.
> The BOMA site sampled for metals (PMio) and hexavalent chromium.
*• The pollutants of interest for BOMA were: arsenic, manganese, nickel, and
hexavalent chromium.
*• Manganese and nickel had the highest daily averages for BOMA, and were one
and two orders of magnitude higher than the daily averages of arsenic and
hexavalent chromium, respectively.
> No concentrations exceeded the short-term risk factors at BOMA.
> A strong negative correlation was calculated between nickel and average
temperature. The pollutants of interest had negative correlations with scalar wind
speed.
*• As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at BOMA. The airshed domain was
somewhat larger in size than other UATMP sites, as the farthest away a back
trajectory originated was over 700 miles.
> The wind rose shows that southwesterly, westerly, and northwesterly winds were
most frequently observed near BOMA.
> Arsenic had the highest annual average-based cancer risk for BOMA. Although
hexavalent chromium had the highest NATA-modeled cancer risk for the census
tract where BOMA is located, the cancer risk was similar to the risk calculated
from the annual average.
> Manganese exhibited the highest annual average-based noncancer risk for
BOMA, although the HQ was very low. Both the annual average-based and
NATA-modeled noncancer risks for BOMA were very low.
> Unlike most UATMP counties, formaldehyde (rather than benzene) was the
highest emitted pollutant with a cancer risk factor in Suffolk County,
Massachusetts, although benzene had the highest cancer toxicity weighted-
emissions. Toluene was the highest emitted pollutant with a noncancer risk
factor, while acrolein had the highest noncancer toxicity weighted-emissions in
Suffolk County.
Michigan.
> DEMI sampled for carbonyl compounds, VOC, and hexavalent chromium, while
ITCMI sampled for SVOC only.
33-13
-------
The pollutants of interest for the DEMI monitoring site were: acrolein,
formaldehyde, carbon tetrachloride, tetrachloroethylene, acetaldehyde, benzene,
hexavalent chromium, 1,3-butadiene, and/>-dichlorobenzene. Benzo(a)pyrene
was the only pollutant to fail screens at ITCMI.
Of the pollutants of interest for DEMI, formaldehyde had the highest daily
average. Formaldehyde averages tended to higher in the warmer seasons than the
colder seasons.
Acrolein exceeded the short-term risk factors at DEMI. All four seasonal
averages of acrolein exceeded the intermediate risk factor.
For DEMI, formaldehyde exhibited positive correlations with the temperature and
moisture parameters. In addition, most of the pollutants of interest exhibited
negative correlations with the scalar wind speed. Correlations between
benzo(a)pyrene and the meteorological parameters for ITCMI were weak.
As illustrated by the composite 24-hour back trajectory maps, the back trajectories
originated from a variety of directions at the Michigan sites. The airshed domains
for these sites were somewhat larger in size than other UATMP sites, as some
back trajectories originated almost 800 miles away.
While winds from a variety of directions were observed near the DEMI
monitoring site, winds with an easterly component were observed less frequently.
Near ITCMI, northwesterly winds were predominant.
A trends analysis was conducted for DEMI. Formaldehyde decreased from 2005
to 2006, but because the 2004 average concentration was skewed by outliers, a
trends assessment beyond 2005 is inconclusive. Benzene and 1,3-butadiene
appear to be holding steady.
Carbon tetrachloride had the highest annual average-based cancer risk for DEMI,
followed by benzene and tetrachloroethylene. By comparison, benzene and 1,3-
butadiene had the highest NATA-modeled cancer risks for the DEMI census tract,
which were both an order of magnitude higher than the annual average-based
cancer risks for these pollutants. The annual average-based and NATA-modeled
cancer risk attributable to benzo(a)pyrene for ITCMI were low.
Acrolein exhibited the highest annual average-based and NATA-modeled
noncancer risks for the DEMI, although the annual average-based noncancer risk
for this pollutant was an order of magnitude higher than the NATA-modeled
noncancer risk. Benzo(a)pyrene does not have a noncancer risk factor.
Benzene was the highest emitted pollutant with a cancer risk factor in both Wayne
and Chippewa Counties, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
33-14
-------
emissions in Chippewa County, but coke oven emissions had the highest cancer
toxicity weighted-emissions in Wayne County. Acrolein had the highest
noncancer toxicity weighted-emissions in both counties.
Minnesota.
> The MTMN site sampled for VOC, metals (TSP), and carbonyl compounds.
*• The pollutants of interest for MIMN were: formaldehyde, acetaldehyde, benzene,
carbon tetrachloride, 1,3-butadiene, manganese, arsenic, nickel, acrolein,
tetrachloroethy 1 ene, and p-dichlorobenzene.
*• Of the pollutants of interest, acetaldehyde and formaldehyde had the highest daily
averages for MIMN. Because this site sampled through the end of April, summer
and autumn averages could not be calculated.
*• Every measured detection of acrolein exceeded the short-term risk factors at
MIMN.
> Correlations between formaldehyde, acetaldehyde, and p-dichlorobenzene and
maximum and average temperatures were strong and positive. While acrolein
exhibited strong correlations with certain meteorological parameters for MIMN,
the low detection rate might skew the correlations.
*• As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at MIMN. The airshed domain was
comparable in size to other UATMP sites, but the map might look much different
with a full sample year's worth of trajectories.
> The wind rose shows that northwesterly and northerly winds were most frequently
observed near MIMN, but southeasterly winds are also common.
*• Due to the short sampling duration, annual averages, and hence cancer and
noncancer risks, could not be calculated. Benzene had the highest cancer risk in
MIMN's census tract according to NATA. The risk attributable to benzene near
MIMN was the third highest modeled cancer risk of any of the site-specific
pollutants of interest. Acrolein had the only NATA-modeled noncancer risk
greater than 1.0 for MIMN.
> Benzene was the highest emitted pollutant with a cancer risk factor in Hennepin
County, Minnesota, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
emissions, while acrolein had the highest noncancer toxicity weighted-emissions
in Hennepin County.
33-15
-------
Mississippi.
> TUMS sampled for VOC and carbonyl compounds, while GPMS sampled for
SNMOC and SVOC in addition to carbonyls and VOC.
> The pollutants of interest common to each Mississippi site were: acrolein,
formaldehyde, carbon tetrachloride, acetaldehyde, benzene, 1,3-butadiene, and
p-di chl orob enzene.
> Of the pollutants of interest for each site, formaldehyde and acetaldehyde had the
highest daily averages for both sites. Formaldehyde tended to be highest in
summer and lowest in winter.
> Acrolein exceeded the short-term risk factors at the Mississippi sites. All four
seasonal averages of acrolein exceeded the intermediate risk factor.
*• Acrolein, carbon tetrachloride, and formaldehyde exhibited moderately strong to
strong positive correlations with the temperature and moisture variables (except
relative humidity) for GPMS. Formaldehyde also exhibited this tendency for
TUMS. Nearly all of the correlations between the pollutants of interest and the
scalar wind speed were negative.
> As illustrated by the composite 24-hour back trajectory maps, the back trajectories
originated from a variety of directions at the Mississippi sites, although less
frequently from the east. The airshed domain was slightly larger at GPMS than at
TUMS, but both are comparable in size to other UATMP sites. The longest
trajectories are those originating from the northwest.
*• Northerly and southerly winds are most often observed near the Mississippi sites,
according to the wind roses. Calm winds were also frequently observed.
> A trends analysis was conducted for the Mississippi sites. Formaldehyde and
benzene both increased from 2004 to 2005 at GPMS, which could be related to
Hurricane Katrina. Formaldehyde decreased at TUMS between 2001 and 2004
and has been steady since.
*• Carbon tetrachloride had the highest annual average-based cancer risk for both
GPMS and TUMS. By comparison, benzene had the highest NATA-modeled
cancer risks for the census tracts in which the Mississippi sites are located. The
benzene NATA-modeled and annual average-based cancer risks were very
similar.
> Acrolein was the only pollutant of interest to have annual average-based and
NATA-modeled noncancer risks greater than 1.0 for the Mississippi sites,
although the annual average based noncancer risks were significantly higher.
33-16
-------
Benzene was the highest emitted pollutant with a cancer risk factor in Harrison
County, while xylenes were the highest emitted pollutant with a noncancer risk
factor. In Lee County, dichloromethane was the highest emitted pollutant with a
cancer risk factor, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
emissions in Harrison County, while hexavalent chromium had the highest cancer
toxicity weighted-emissions in Lee County. Acrolein had the highest noncancer
toxicity weighted-emissions in both counties.
Missouri.
The S4MO site sampled for VOC, metals (PMi0), hexavalent chromium, and
carbonyl compounds.
The pollutants of interest for S4MO were: formaldehyde, acetaldehyde, benzene,
carbon tetrachloride, 1,3-butadiene, manganese, arsenic, cadmium, acrolein,
tetrachloroethy 1 ene, and p-dichlorobenzene.
Of the pollutants of interest, formaldehyde had the highest daily average for
S4MO. Formaldehyde tended to be highest in the summer and acetaldehyde was
highest in the spring.
Acrolein exceeded the short-term risk factors at S4MO. Seasonal averages of
acrolein, where they could be calculated, exceeded the intermediate risk factor.
Correlations between formaldehyde and maximum, average, dew point, and wet
bulb temperatures were strong and positive, which support the trends shown by
the seasonal averages. Carbon tetrachloride exhibited a similar tendency with the
temperature parameters. Correlations with scalar wind speed were all negative.
As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at S4MO, although less frequently from the
east and southeast. The airshed domain was larger in size than other UATMP
sites, with trajectories more than 800 miles long.
The wind rose shows that southeasterly and southerly winds were most frequently
observed near S4MO.
A trends analysis was conducted for S4MO. Benzene, formaldehyde, and 1,3-
butadiene averages have decreased in recent years.
Carbon tetrachloride and benzene had the highest annual average-based cancer
risks for S4MO. Benzene had the highest NATA-modeled cancer risk for the
S4MO census tract, although the risk was an order of magnitude higher than
annual average-based cancer risk for benzene.
33-17
-------
> Acrolein exhibited the highest annual average-based and NATA-modeled
noncancer risks for S4MO site.
*• Benzene was the highest emitted pollutant with a cancer risk factor in St Louis
County, Missouri, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
emissions, while acrolein had the highest noncancer toxicity weighted-emissions
in St Louis County.
New Jersey.
*• The New Jersey sites sampled for VOC and carbonyl compounds.
> The pollutants of interest common to all four New Jersey sites are: formaldehyde,
acetaldehyde, benzene, carbon tetrachloride, 1,3-butadiene, acrolein, and
tetrachl oroethy 1 ene.
> Of the pollutants of interest, formaldehyde and acetaldehyde had the highest daily
average for the New Jersey sites. Formaldehyde was higher in summer; carbon
tetrachloride was highest in summer and autumn; and benzene and 1,3-butadiene
were highest in autumn and winter.
> Every acrolein concentration exceeded the short-term ATSDR MRL and most
exceeded the CALEPA REL at the New Jersey sites. Every seasonal average,
where there were enough measured detections, exceeded the intermediate-term
risk factor.
*• For most of the New Jersey sites, acetaldehyde, formaldehyde, and carbon
tetrachloride exhibited strong positive correlations with the temperature
parameters, and formaldehyde and carbon tetrachloride exhibited strong positive
correlations with the moisture parameters.
*• As illustrated by the composite 24-hour back trajectory maps, the back trajectories
originated from a variety of directions at the New Jersey sites, although less
frequently from the east. The airshed domains were comparable in size to other
UATMP sites, as some back trajectories originated more than 600 miles away.
> The wind roses show that winds with a westerly component were more frequently
observed than winds with an easterly component near CANJ and ELNJ, while
calm winds were observed over half the time near CFINJ and NBNJ.
> A trends analysis shows that the New Jersey sites have been sampling for an
extended period of time as part of the UATMP. Concentrations of formaldehyde,
benzene, and 1,3-butadiene have been decreasing slightly over the last few years
at CANJ; formaldehyde and benzene exhibit deceasing trends at CFINJ; benzene
33-18
-------
and 1,3-butadiene are decreasing while formaldehyde is increasing at ELNJ; and
benzene and formaldehyde decreased at NBNJ.
*• Carbon tetrachloride had the highest annual average-based cancer risk for CANJ,
CHNJ, and NBNJ, while acetaldehyde had the highest annual average-based
cancer risk for ELNJ. Benzene had the highest NATA-modeled cancer risk for all
four New Jersey sites.
*• Acrolein had the highest annual average-based and NATA-modeled noncancer
risk for the New Jersey sites. Although the risk based on the annual average was
an order of magnitude higher than the NATA-modeled risk for CANJ, CFINJ, and
NBNJ, the acrolein risks for ELNJ were very similar.
> Benzene was the highest emitted pollutant with a cancer risk factor in Camden,
Morris, Union, and Middlesex Counties, while toluene was the highest emitted
pollutant with a noncancer risk factor in these four counties. Benzene also had
the highest cancer toxicity weighted-emissions in each county, while acrolein had
the highest noncancer toxicity weighted-emissions in each county.
North Carolina.
> The two North Carolina sites sampled for carbonyl compounds.
*• Two carbonyl compounds have risk screening values, formaldehyde and
acetaldehyde. These pollutants failed screens at each site and were the pollutants
of interest for each site.
*• Formaldehyde tended to have the highest daily average for each site, although the
difference was not statistically significant. Seasonal averages could not be
calculated due to the short sampling duration combined with the l-in-12 sampling
schedule.
*• No concentrations of acetaldehyde or formaldehyde exceeded the short-term risk
factors at the North Carolina sites.
*• Formaldehyde exhibited strong positive correlations with the temperature
parameters at the North Carolina sites, and both formaldehyde and acetaldehyde
exhibited strong negative correlations with relative humidity.
*• As illustrated by the composite 24-hour back trajectory maps, the back trajectories
originated from a variety of directions at C ANC and RTPNC, although primarily
from the southwest. However, the maps might look much different with a full
sample year's worth of trajectories.
33-19
-------
> Similar to the back trajectories, the wind roses show that southwesterly winds
were frequently observed near the North Carolina sites. Again, the wind roses
might look much different with a full sample year's worth of wind observations.
> A trends analysis was conducted for CANC and RTPNC. Inclusion of confidence
intervals shows that formaldehyde concentrations have changed little at these sites
over the last few years.
*• Annual averages could not be calculated for the North Carolina sites due to the
short sampling duration; therefore, theoretical cancer risks could not be
calculated. However, NATA-modeled cancer risks for acetaldehyde for the
RTPNC census tract were roughly twice as high as the CANC census tract.
NATA-modeled formaldehyde cancer risks were low for both sites' census tracts.
> NATA-modeled noncancer risks for acetaldehyde and formaldehyde at the North
Carolina sites were low.
> While benzene was the highest emitted pollutant with a cancer risk factor in
Durham County, North Carolina, formaldehyde was the highest emitted pollutant
with a cancer risk factor in Montgomery County. Benzene had the highest cancer
toxicity weighted-emissions in both counties.
> Toluene was the highest emitted pollutant with a noncancer risk factor in both
Durham and Montgomery Counties. Yet, acrolein had the highest noncancer
toxicity weighted-emissions.
Oklahoma.
- CNEP sampled for VOC only, while the Tulsa sites (TOOK, TSOK, and TUOK)
sampled for VOC, carbonyl compounds and metals (TSP).
*• The pollutants of interest common to each Oklahoma site were acrolein, benzene,
1,3-butadiene, and carbon tetrachloride.
> Acrolein had the highest daily average for CNEP; xylenes had the highest daily
average for TOOK and TSOK; and formaldehyde had the highest daily average
for TUOK. Seasonal average availability varied by site due to the varied start
dates.
> Every acrolein concentration exceeded the short-term ATSDR MRL and most
exceeded the CALEPA REL at the Oklahoma sites. Every seasonal average,
where there were enough measured detections, exceeded the intermediate-term
risk factor.
> Pearson correlations with the meteorological parameters for CNEP were weak.
Several pollutants of interest for the Tulsa sites exhibited strong positive
33-20
-------
correlations with the temperature and moisture variables, especially
formaldehyde.
As illustrated by the composite 24-hour back trajectory maps for the Oklahoma
sites, back trajectories originated primarily from the north and south. The airshed
domains were larger in size for these sites than other UATMP sites, as some back
trajectories originated over 800 miles away.
The wind roses for the Oklahoma sites show that southerly winds were
predominant during the period of sampling for each site.
Annual averages, and hence cancer and noncancer risks, could not be calculated
for the CNEP and TSOK sites. Benzene had the highest annual average-based
cancer risk for both TOOK and TUOK. Benzene also had the highest NATA-
modeled cancer risk for each of the sites.
Acrolein had the highest the only NATA-modeled noncancer risk greater than 1.0
for the Oklahoma sites and for TOOK and TUOK, the only annual average-based
noncancer risk greater than 1.0. However, the risks based on the annual average
were an order of magnitude higher.
Benzene was the highest emitted pollutant with a cancer risk factor in both Mayes
and Tulsa Counties. Benzene also had the highest cancer toxicity weighted-
emissions in Tulsa County, while arsenic had the highest cancer toxicity
weighted-emissions in Mayes County. Toluene was the highest emitted pollutant
with a noncancer toxicity factor in both counties, while acrolein had the highest
noncancer toxicity weighted-emissions.
Oregon.
The LAOR site sampled for hexavalent chromium only. Although this pollutant
did not fail any screens, it was still considered this site's pollutant of interest in
order to facilitate analysis.
Seasonal average concentrations of hexavalent chromium could not be calculated
due to the short sampling duration.
Hexavalent chromium does not have acute risk factors.
Although some Pearson correlations were strong, the low number of detects likely
skewed the correlations.
As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated primarily from the southwest. However, the map might look much
different with a full sample year's worth of trajectories.
33-21
-------
> The wind rose shows that southerly and southeasterly winds prevailed near
LAOR.
*• Annual averages could not be calculated for LAOR due to the short sampling
duration; therefore, theoretical cancer and noncancer risks could not be calculated.
The NATA-modeled cancer and noncancer risks attributable to hexavalent
chromium for LAOR were low.
> Benzene was the highest emitted pollutant with a cancer risk factor in Union
County, Oregon, while toluene was the highest emitted pollutant with a noncancer
risk factor. Benzene follows POM as non-15 PAH as the pollutant highest cancer
toxicity weighted-emissions, while acrolein had the highest noncancer toxicity
weighted-emissions.
Puerto Rico.
*• The Puerto Rico sites sampled for VOC and carbonyl compounds.
> The pollutants of interest common to both sites were: formaldehyde,
acetaldehyde, benzene, carbon tetrachloride, 1,3-butadiene, acrolein, xylenes, and
p-di chl orob enzene.
> Of the pollutants of interest, dichloromethane had the highest daily average
concentration for BAPR, while total xylenes had the highest daily average
concentration for SJPR.
> Every acrolein concentration exceeded the ATSDR short-term risk factor at SJPR
and BAPR and most exceeded the CALEPA REL. Every seasonal average of
acrolein exceeded the intermediate-term risk factor for the Puerto Rico sites.
> Correlations between carbon tetrachloride and the temperature and moisture
parameters were strong and positive for BAPR, while the remaining correlations
were weak. Acetaldehyde exhibited strong negative correlations with these same
parameters for SJPR, while the remaining correlations were weak.
> As illustrated by the composite 24-hour back trajectory maps, the back trajectories
originated primarily the northeast and east at the Puerto Rico sites. The airshed
domains were comparable in size to other UATMP sites, as the farthest away a
back trajectory originated is about 700 miles.
*• The wind rose shows that easterly and east-northeasterly winds were most
frequently observed near BAPR and SJPR.
> /7-Dichloromethane had the highest annual average-based cancer risk for both
BAPR and SJPR, although NATA-modeled risks from this pollutant were an
order of magnitude lower. Dichloromethane had the highest NATA-modeled
cancer risk for BAPR, which was the second highest NATA-modeled cancer risk
33-22
-------
for all site-specific pollutants of interest. Tetrachloroethylene had the highest
NATA-modeled cancer risk for SJPR.
*• Acrolein had the highest annual average-based and NATA-modeled noncancer
risk for BAPR and SJPR, although the risk based on the annual average was an
order of magnitude higher.
*• Benzene was the highest emitted pollutant with a cancer risk factor in Bayamon
Municipio, Puerto Rico, while dichloromethane was the highest emitted pollutant
with a cancer risk factor in Barceloneta Municipio. These two pollutants also had
the highest cancer toxicity weighted-emissions in each respective county.
Toluene was the highest emitted pollutant with a noncancer risk factor in
Bayamon Municipio, while dichloromethane was the highest emitted pollutant
with a noncancer risk factor in Barceloneta Municipio. Acrolein, however, had
the highest noncancer toxicity weighted-emissions in both municipios.
Rhode Island.
> The PRRI site sampled for hexavalent chromium only, and was therefore this
site's only pollutant of interest. Hexavalent chromium failed three screens at
PRRI.
> The concentration of hexavalent chromium was highest in the summer and lowest
in winter, although the difference is not statistically significant.
> Hexavalent chromium does not have acute risk factors. While an intermediate-
term risk factor is available, it was not exceeded at PRRI.
> Correlations between hexavalent chromium for PRRI and the meteorological
parameters tended to be weak.
> As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at PRRI. The airshed domain was
comparable in size to other UATMP sites, as the farthest away a back trajectory
originated is nearly 700 miles.
> The wind rose shows that winds with a westerly component were observed more
frequently than winds with an easterly component near PRRI.
> The annual average-based cancer risk attributable to hexavalent chromium was an
order of magnitude lower than the NATA-modeled cancer risk for PRRI.
Noncancer risk from hexavalent chromium was very low.
> Benzene was the highest emitted pollutant with a cancer risk factor in Providence
County, Rhode Island, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
emissions, while acrolein had the highest noncancer toxicity weighted-emissions.
33-23
-------
South Carolina.
> The CHSC site sampled for hexavalent chromium only. Although this pollutant
did not fail any screens, it was still considered this site's pollutant of interest in
order to facilitate analysis.
> Due to the low detection rate, a winter and autumn seasonal average concentration
of hexavalent chromium could not be calculated.
> Hexavalent chromium does not have acute risk factors. While an intermediate-
term risk factor is available, it was not exceeded at CHSC in the seasons where
averages could be calculated.
> Correlations between hexavalent chromium at CHSC and the meteorological
parameters were weak.
*• As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at CHSC. The airshed domain was
comparable in size to other UATMP sites, as the farthest away a back trajectory
originated is greater than 600 miles.
> The wind rose shows that calm winds were observed for one-third of
measurements. Southwesterly winds were also common near CHSC.
*• The annual average-based and NATA-modeled cancer and noncancer risks
attributable to hexavalent chromium for CHSC were low.
*• Benzene was the highest emitted pollutant with a cancer risk factor in Chesterfield
County, South Carolina, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
emissions, while acrolein had the highest noncancer toxicity weighted-emissions.
South Dakota.
> The South Dakota sites sampled for VOC, SNMOC, and carbonyl compounds.
*• The pollutants of interest common to both sites were: formaldehyde,
acetaldehyde, benzene, carbon tetrachloride, 1,3-butadiene, and acrolein.
*• Of the pollutants of interest, acetaldehyde and formaldehyde had the highest daily
average concentrations for both sites, although the concentrations for SFSD were
more than twice the average concentrations for CUSD. Formaldehyde was
highest in summer for both sites, and acetaldehyde was higher in summer and
autumn for SFSD.
33-24
-------
> Every acrolein concentration exceeded the short-term risk factors at CUSD and
SFSD. Every seasonal average of acrolein, where it could be calculated,
exceeded the intermediate-term risk factor for the South Dakota sites.
*• Correlations between carbon tetrachloride and the maximum, average, dew point
and wet bulb temperatures were strong and positive for both South Dakota sites.
Formaldehyde also had strong positive correlations with these parameters for
CUSD. Acrylonitrile also had strong positive correlations with these parameters
for SFSD, but was detected few times.
> The composite 24-hour back trajectory maps for CUSD and SFSD were different
from each other. Trajectories rarely originated from the north and east at CUSD,
while trajectories originated from a variety of directions at SFSD. The airshed
domains for these sites were larger in size than most other UATMP sites, as
trajectories originated greater than 700 miles away.
> The wind roses show that southwesterly, westerly, and northwesterly winds were
most frequently observed near CUSD, while winds from other directions were
frequently observed near SFSD.
*• A trends analysis was conducted for SFSD and CUSD. Formaldehyde
concentrations have been decreasing at CUSD, while benzene and 1,3-butadiene
have changed little. Formaldehyde and benzene have not changed significantly at
SFSD, while 1,3-butadiene has decreased somewhat.
> Carbon tetrachloride had both the highest annual average-based and NATA-
modeled cancer risk for CUSD. The annual average-based cancer risk from
acrylonitrile was slightly higher than the carbon tetrachloride risk for SFSD,
although carbon tetrachloride had the NATA-modeled risk for SFSD.
> Acrolein had the highest annual average-based and NATA-modeled noncancer
risk for CUSD and SFSD, although the risk based on the annual average was an
order of magnitude higher.
> Benzene was the highest emitted pollutant with a cancer risk factor in both Custer
and Minnehaha Counties, while toluene was the highest emitted pollutant with a
noncancer risk factor in both counties. Benzene also had the highest cancer
toxicity weighted-emissions, while acrolein had the highest noncancer toxicity
weighted-emissions.
Tennessee.
> The Tennessee sites sampled for VOC and carbonyl compounds.
33-25
-------
The pollutants of interest common to both sites were: formaldehyde,
acetaldehyde, benzene, carbon tetrachloride, 1,3-butadiene, acrolein, andp-
dichlorobenzene.
Of the pollutants of interest, formaldehyde had the highest daily average
concentration for both MSTN and LDTN. Formaldehyde tended to be highest
during the summer for both sites.
Every acrolein concentration exceeded the ATSDR short-term risk factor at
LDTN and MSTN and most exceeded the CALEPA REL. Every seasonal
average of acrolein exceeded the intermediate-term risk factor for the Tennessee
sites.
Correlations between formaldehyde and the maximum, average, dew point, and
wet bulb temperatures were strong and positive for both sites. /?-Dichlorobenzene
exhibited a similar trend for MSTN but not for LDTN. Nearly all the correlations
with wind speed were negative for both sites.
As illustrated by the composite 24-hour back trajectory maps, the back trajectories
originated from at variety of directions at the Tennessee sites. The airshed
domains were comparable in size to other UATMP sites, as the farthest away a
back trajectory originated is greater than 600 miles.
The wind rose shows that southwesterly and westerly winds were most frequently
observed near LDTN and MSTN.
A trends analysis for LDTN shows that formaldehyde and 1,3-butadiene has been
decreasing and benzene has changed little.
Carbon tetrachloride had the highest annual average-based cancer risk for LDTN
and MSTN, while benzene had the highest NATA-modeled cancer risk for the
sites.
Acrolein had the highest annual average-based and NATA-modeled noncancer
risk for LDTN and MSTN, although the risk based on the annual average was an
order of magnitude higher.
Benzene was the highest emitted pollutant with a cancer risk factor in Loudon
County, Tennessee, and also had the highest cancer toxicity weighted-emissions
in this county. Carbon disulfide was the highest emitted pollutant with a
noncancer risk factor in Loudon County, while acrolein had the highest noncancer
toxicity weighted-emissions.
33-26
-------
Texas.
The Austin and Round Rock, Texas sites began sampling in late June or early July
2005 and continued through June 2006. They sampled for VOC, carbonyl
compounds, TNMOC, and metals (PMio). In addition, the El Paso, Texas site
sampled VOC from March 2005 to March 2006. In order to facilitate analysis,
data from the entire year's worth of sampling for each site were utilized in the
site-specific analyses.
The pollutants of interest common to each Texas site were: acrolein, carbon
tetrachloride, benzene, 1,3-butadiene, and/>-dichlorobenzene.
Of the pollutants of interest for each Austin or Round Rock site, acrolein had the
highest daily average for each site, followed by formaldehyde. Total xylenes had
the highest daily average for YDSP.
Acrolein exceeded the short-term risk factors at all of the Texas sites each time it
was measured. Where seasonal averages could be calculated for acrolein, they
exceeded the intermediate risk factors.
Acrolein, formaldehyde, and/>-dichlorobenzene exhibited positive correlations
with the temperature and moisture parameters for most of the Austin sites,
although WETX did not follow this trend. Most of the pollutants exhibited
negative correlations with the temperature and moisture parameters for YDSP.
Nearly all of the correlations with scalar wind speed for the Texas sites were
negative.
As illustrated by the composite 24-hour back trajectory maps for the
Austin/Round Rock sites, the back trajectories originated primarily from the
southeast, although the longest trajectories originated from the north. For the El
Paso site, trajectories originated primarily from the southeast and southwest, and
the airshed domain was much smaller than the other Texas sites.
The wind roses show that southeasterly and southerly winds were observed most
frequently near the Austin/Round Rock sites. Northerly, easterly, and westerly
winds prevailed near YSDP.
The pollutants with the highest annual-average based cancer risks in the
Austin/Round Rock census tracts were the pollutants that were detected
infrequently, such as hexachloro-1,3-butadiene and 1,2-dibromoethane. Benzene
had the highest NATA-modeled cancer risks in the Austin/Round Rock census
tracts, which was also on the high end for the annual-average based cancer risks.
Benzene exhibited the highest annual average-based and NATA-modeled cancer
risks at the El Paso site.
33-27
-------
> Acrolein exhibited the highest annual average-based and NATA-modeled
noncancer risks at each of the Texas sites. However, the annual average-based
noncancer risks attributable to acrolein for the Austin/Round Rock sites were the
highest calculated of all pollutants for any UATMP site.
> Benzene was the highest emitted pollutant with a cancer risk factor in Travis,
Williamson, and El Paso Counties, Texas, while toluene was the highest emitted
pollutant with a noncancer risk factor in each of these counties. Benzene also had
the highest cancer toxicity weighted-emissions in Travis, Williamson, and El Paso
Counties, while acrolein had the highest noncancer toxicity weighted-emissions in
these counties.
Utah.
> The BTUT site sampled for VOC, SNMOC, metals (PMio), hexavalent
chromium, and carbonyl compounds.
> The pollutants of interest at BTUT were: formaldehyde, acetaldehyde, benzene,
carbon tetrachloride, 1,3-butadiene, manganese, arsenic, cadmium, acrolein, and
tetrachl oroethy 1 ene.
> Of the pollutants of interest, formaldehyde had the highest daily average for
BTUT. Formaldehyde was significantly higher in the summer.
*• Acrolein exceeded the short-term risk factors at BTUT. Seasonal averages of
acrolein, where they could be calculated, exceeded the intermediate risk factor.
*• Strong correlations were calculated between acetaldehyde, formaldehyde, and
manganese and the temperature and moisture variables.
> As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at BTUT. The airshed domain was smaller
in size than other UATMP sites, with the longest trajectory originating just over
500 miles away.
*• The wind rose shows that southeasterly and southerly winds were most frequently
observed near BTUT.
> A trends analysis was conducted for BTUT. Concentrations of benzene have
decreased slightly; 1,3-butadiene is remaining steady; and formaldehyde
concentrations have leveled off after the increase in 2004.
> Benzene had the highest annual average-based cancer risks for BTUT, followed
closely by carbon tetrachloride. Benzene had the highest NATA-modeled cancer
risk for the BTUT census tract, which was similar to the annual average based-
risk.
33-28
-------
Acrolein exhibited the highest annual average-based and NATA-modeled
noncancer risks for BTUT site.
Benzene was the highest emitted pollutant with a cancer risk factor in Davis
County, Utah, while toluene was the highest emitted pollutant with a noncancer
risk factor. Benzene also had the highest cancer toxicity weighted-emissions,
while acrolein had the highest noncancer toxicity weighted-emissions in Davis
County.
Vermont.
The UNVT site sampled for hexavalent chromium only, and was therefore this
site's only pollutant of interest. Hexavalent chromium failed one screen at
UNVT.
The low number of measured detections of hexavalent chromium prevented
winter and autumn seasonal averages from being calculated. The large
confidence interval indicates that outliers likely impacted the summer average
concentration.
Hexavalent chromium does not have acute risk factors. While an intermediate-
term risk factor is available, it was not exceeded for UNVT.
Correlations between hexavalent chromium for UNVT and the meteorological
parameters were weak.
As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated from a variety of directions at UNVT. The airshed domain was rather
large, as the farthest away a back trajectory originated is greater than 700 miles.
The wind rose shows that calm winds prevailed near UNVT.
The annual average-based cancer risk attributable to hexavalent chromium was an
order of magnitude higher than the NATA-modeled cancer risk for UNVT,
although both are low. Noncancer risk from hexavalent chromium was very low.
Benzene was the highest emitted pollutant with a cancer risk factor in Chittenden
County, Vermont, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
emissions, while acrolein had the highest noncancer toxicity weighted-emissions.
33-29
-------
Washington.
> The SEWA site sampled for hexavalent chromium only, and was therefore this
site's only pollutant of interest. Hexavalent chromium failed one screen at
SEWA.
> The gap in sampling from March through September at SEWA prevented most
seasonal averages from being calculated.
> Hexavalent chromium does not have acute risk factors. While an intermediate-
term risk factor is available, it was not exceeded at SEWA in winter.
> Most of the correlations between hexavalent chromium for SEWA and the
meteorological parameters were weak. The one exception is the correlation with
scalar wind speed.
*• As illustrated by the composite 24-hour back trajectory map, the back trajectories
originated primarily from the south and southwest. However, the map might look
much different with a full sample year's worth of trajectories.
*• The wind rose shows that southerly and southeasterly winds prevailed near
SEWA.
*• Annual averages could not be calculated for SEWA due to the short sampling
duration; therefore, theoretical cancer and noncancer risks could not be calculated.
The NATA-modeled cancer risk attributable to hexavalent chromium for SEWA
was higher than other sites that sampled hexavalent chromium. The NATA-
modeled noncancer risk was low.
> Benzene was the highest emitted pollutant with a cancer risk factor in King
County, Washington, while toluene was the highest emitted pollutant with a
noncancer risk factor. Benzene also had the highest cancer toxicity weighted-
emissions, while acrolein had the highest noncancer toxicity weighted-emissions.
Wisconsin.
> The MVWI site sampled for hexavalent chromium only. Although this pollutant
did not fail any screens, it was still considered this site's pollutant of interest in
order to facilitate analysis. MAWI sampled for carbonyl compounds and VOC
through the end of February. The pollutants of interest for MAWI were:
formaldehyde, acetaldehyde, benzene, carbon tetrachloride, 1,3-butadiene, and
hexachl oro-1,3 -butadi ene.
*• Seasonal average concentrations of hexavalent chromium for MWVI did not vary
much from season to season. Of the pollutants of interest for MAWI,
33-30
-------
formaldehyde and acetaldehyde had the highest daily average concentrations.
Only winter seasonal averages could be calculated for this site.
*• No pollutants exceeded the short term risk factors at the Wisconsin sites.
> Although some Pearson correlations for MAWI were strong, the low number of
detects likely skewed the correlations. Hexavalent chromium exhibited strong
positive correlations with the dew point and wet bulb temperatures.
> As illustrated by the composite 24-hour back trajectory map for MAWI, the back
trajectories originated primarily from the north and west. However, the map
might look much different with a full sampling year's worth of trajectories. The
back trajectories originated from a variety of directions at MVWI. The airshed
domain was rather large in size for this site, as the farthest away a back trajectory
originated was nearly 800 miles.
> The wind rose shows that northwesterly winds prevailed near MAWI during the
sampling period. Westerly winds were commonly observed near MVWI,
although winds from a variety of directions were also observed.
*• Annual averages could not be calculated for MAWI due to the short sampling
duration; therefore, theoretical cancer and noncancer risks could not be calculated.
Benzene exhibited the highest cancer risk based on NATA for the MAWI census
tract. The annual average-based and NATA-modeled cancer and noncancer risks
attributable to hexavalent chromium for MWVI were low.
> Benzene was the highest emitted pollutant with a cancer risk factor in Dane and
Dodge Counties, Wisconsin, while toluene was the highest emitted pollutant with
a noncancer risk factor. Benzene also was the pollutant highest cancer toxicity
weighted-emissions in these counties. While acrolein had the highest noncancer
toxicity weighted-emissions in Dodge County, manganese had the highest
noncancer toxicity weighted-emissions in Dane County.
33.1.4 Data Quality
Based on data from duplicate and collocated samples (where applicable), the precision of
the sampling methods and concentration measurements was determined for the 2006 UATMP
using relative percent difference (RPD), coefficient of variation (CV), and average concentration
difference calculations. The overall precision was well within UATMP data quality objectives
and monitoring method guidelines. Sampling and analytical method accuracy is assured by
using proven methods and following strict quality control and quality assurance guidelines.
33-31
-------
33.2 Recommendations
In light of the lessons learned from the 2006 UATMP, a number of recommendations for
future National Monitoring Programs are supported:
• Incorporate/Update Risk in State Implementation Plans (SIPs). Use risk calculations
to design SIPs to implement policies that will reduce the potential for human health
risk.
• Encourage state/local/tribal agencies to assess, refine, and/or verify HAP and VOC
emission inventories. State/local/tribal agencies should compare the UATMP
ambient data with existing emissions inventories to, at the very least, identify and/or
verify emission sources of concern and assess source category completeness. The
emissions inventory would then be used to develop modeled concentrations useful to
compare against ambient monitoring data.
• Continue to identify and implement improvements to the sampling and analytical
methods. The improvements made to the analytical methods prior to the 1999-2000
UATMP allowed for measurement of ambient air concentrations of 11 pollutants that
were not measured during previous programs. Sponsoring agencies and a variety of
interested parties now have important information about air quality within their urban
areas. Further research is encouraged to identify other method improvements that
would allow the UATMP to better characterize urban air pollution.
• Continue to strive to develop standard conventions for interpreting air monitoring
data. The lack of consistent approaches to present and summarize ambient air
monitoring data complicates or invalidates comparisons between different studies.
Additional research should be conducted on the feasibility of establishing standard
approaches for analyzing and reporting air monitoring data. The approach in
determining "pollutants of interest" and the presentation of daily, seasonal, and
annual averages are attempts at this standardization.
• Prepare a report characterizing all years of the UATMP and then update it yearly to
better assess trends in concentrations and risk and better understand the nature of U.S.
urban air pollution.
• Consider more rigorous study of the impact of automobile emissions on ambient air
quality using the complete UATMP data set. Because the UATMP has monitoring
sites where years of continuous data are collected, a real opportunity exists to
evaluate the importance and impact of automobile emissions on ambient air quality.
Suggested areas of study include reformulated gas, additional signature compound
assessments and parking lot characterizations.
• Update site characterization parameters. Several characterization parameters, such
as average daily traffic volume for the monitoring sites are provided in AQS by the
agency responsible for the site and are provided in this report. Many of these
33-32
-------
parameters are ten or more years old. Updated information regarding such
parameters would provide higher quality information for understanding the dynamics
surrounding each monitoring site.
Encourage continued and long term participation in the UATMP. Continuing
ambient air monitoring at fixed locations can provide insight into long term trends in
urban air quality and the potential for urban air pollution to cause adverse health
effects among the general population. Therefore, state and local agencies should be
strongly encouraged either to develop and implement their own ambient air
monitoring programs or to participate in future National Monitoring Programs.
Encourage year-round participation in the UATMP. Many of the analyses presented
in the 2006 UATMP require a full year of data to be most useful and representative of
conditions experienced at each specified location. Therefore, state and local agencies
should be strongly encouraged to implement year-long ambient air monitoring
programs in addition to participating in future UATMP monitoring efforts.
Encourage case studies based on findings from the UATMP. Often, the UATMP will
identify an interesting tendency or trend, or highlight an event at a particular site(s).
An example from the 2006 report includes the observation of high hexavalent
chromium concentrations on July 4th, 2006. Further examination of the data in
conjunction with meteorological phenomena and potential emissions events or
incidents, or further site characterization may help identify state and local agencies
pinpoint issues affecting air quality in their area.
33-33
-------
34.0 References
ATSDR, 2006. Agency for Toxics Substances and Disease Registry (ATSDR). Minimal Risk
Levels for Hazardous Substances. December 2005. Internet address:
http://www.atsdr.cdc.gov/mrls.html
CARB, 2006. California Air Resources Board (ARE). Consolidated Table of OEHHA / ARE
Approved Risk Assessment Health Values. April 25, 2005. Internet address:
http://www.arb.ca.gov/toxics/healthval/healthval.htm
Conner, et al., 1995. "Transportation-Related Volatile Hydrocarbon Source Profiles Measured in
Atlanta." Teri L. Conner, William A. Lonneman, Robert L. Seila. Journal of the Air and
Waste Management Association, 45: 383-394. 1995.
Draxler, R.R. and Rolph, G.D., 2003. HYSPLIT (Hybrid Single-Particle Lagrangian Integrated
Trajectory) Model access via NOAA ARL READY Website
(http://www.arl.noaa.gov/readv/hysplit4.html). NOAA Air Resources Laboratory. Silver
Spring. MD.
EIA, 2006. Energy Information Administration. Car Registration by State. October 2004.
EPA, 1996. "Semivolatile Organic Compounds by Gas Chromatography/Mass Spectrometry
(GC/MS), Revision 3." U.S. Environmental Protection Agency. December 1996.
Internet address: http://www.epa.gov/epaoswer/hazwaste/test/pdfs/8270c.pdf
EPA, 1998. "Technical Assistance Document for Sampling and Analysis of Ozone Precursors."
U.S. Environmental Protection Agency, National Exposure Laboratory. EPA/600-R-
98/161. September 1998.
EPA, 1999a. "Compendium Method TO-11 A: Determination of Formaldehyde in Ambient Air
Using Adsorbent Cartridge Followed by High Performance Liquid Chromatography
(HPLC)." U.S. Environmental Protection Agency, Center for Environmental Research
and Information. EPA/625/R-96/010b. January, 1999.
EPA, 1999b. "Compendium Method TO-15: Determination of Volatile Organic Compounds
(VOC) in Ambient Air Collected in Specially-Prepared Canisters and Analyzed by Gas
Chromatography/Mass Spectrometry (GC/MS)." U.S. Environmental Protection Agency,
Center for Environmental Research and Information. EPA/625/R-96/010b.
January, 1999.
EPA, 1999c. "Compendium Method TO-13: Determination of Polycyclic Aromatic
Hydrocarbons (PAHs) in Ambient Air Using Gas Chromatography/Mass Spectrometry
(GC/MS)." U.S. Environmental Protection Agency, Center for Environmental Research
and Information. EPA/625/R-96/010b. January 1999.
34-1
-------
EPA, 1999d. "Compendium Method IO-3.5: Determination of Metals in Ambient Particulate
Matter Using Inductively Coupled Plasma/Mass Spectrometry (ICP/MS)." U.S.
Environmental Protection Agency, Center for Environmental Research and Information.
EPA/625/R-96/010a. June 1999.
EPA, 2005a. Evaluation Report. "Progress Made in Monitoring Ambient Air Toxics, But
Further Improvements Can Increase Effectiveness." Report No. 2005-P-00008. March
2, 2005.
EPA, 2005b. 40 CFR Part 136, Appendix B. Definition and Procedure Determination of the
Method Detection Limit, Revision 1.11.
EPA, 2006a. 2002 National Emissions Inventory (NEI) Data and Documentation. Data
retrieved from ftp://ftp.epa.gov/EmisInventory/2002finalnei/
EPA, 2006b. Standard Operating Procedure for the Determination of Hexavalent Chromium in
Ambient Air Analyzed by Ion Chromatography (1C). June 2006. Internet address:
http ://www. epa. gov/ttn/amtic/airtox.html.
EPA, 2006c. The National-Scale Air Toxics Assessment (NATA) for 1999. Internet address:
http ://www. epa. gov/ttn/nata_l 999/
EPA, 2006d. A Preliminary Risk-based Screening Approach for Air Toxics Monitoring Data
Sets. Air, Pesticides, and Toxics Management Division. Atlanta, GA. February 2006.
Internet address: http://www.epa.gov/docs/region04/air/airtoxic/Screening-041106-
KM.pdf
EPA, 2006e. Revisions to Ambient Air Monitoring Regulations; Final Rule. 40 CFR Parts 53
and 58. October 17, 2006. Internet address:
http://www.epa.gov/ttn/amtic/files/ambient/pm25/pt535806.pdf
EPA, 2007a. Technical Assistance for the National Ambient Air Toxics Trends and Assessment
Program. Emissions - Revision 1, Office of Air Quality Planning and Standards
(OAQPS), Modeling, and Analysis Division (EMAD). RTF, NC. 336 pp. November 1,
2007.
EPA, 2007b. Pollutants and Sources. EPA TTN Air Toxics Web Site. Last updated June 6,
2007. Internet address: http://www.epa.gov/ttn/atw/pollsour.html
EPA, 2007c. "2005 Urban Air Toxics Monitoring Program (UATMP) - Hexavalent Chromium,
Final Report." EPA-68-D-03-049. February 2007.
EPA, 2007d. "1990-2002 NEI HAP Trends: Success of CAA Air Toxic Programs in Reducing
HAP Emissions and Risk. Paper presented at the 16th Annual International Emission
Inventory Conference. Raleigh, NC. May 2007. Internet address:
http://www.epa.gOv/ttn/chief/conference/eil6/session6/a.pope.pdf
34-2
-------
ERG, 2006/2007. Eastern Research Group, Inc. "Support for the EPA National Monitoring
Programs (NMOC, UATMP, PAMS, HAPs, and NATTS), Quality Assurance Project
Plan, Category 1, 2006/2007." Internet address:
http://www.ergweb2.com/uatmp/user/index.cfm
Lakes, 2006. Lakes Environmental, WRPLOT View. Internet address:
http://www.weblakes.com/lakewrpl.html. 2006.
NLMa. U.S. National Library of Medicine. Internet address:
http://toxtown. nlm. nih. gov/text version/chemical s.php?id= 10
NLMb. U.S. National Library of Medicine. Hazardous Substances Data Bank. Internet address:
http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen7HSDB
NRC, 1991. "Rethinking the Ozone Problem in Urban and Regional Air Pollution. "National
Research Council: National Academy Press, 1991.
Rogers and Yau, 1989. "A Short Course in Cloud Physics." R. R. Rogers and M. K. Yau.
Pergamon Press. 1989.
Ruffner and Bair, 1987. "The Weather Almanac." James A. Ruffner and Frank E. Bair. Gale
Research Company. 1987.
TCEQ, 2002. Texas Commission on Environmental Quality (TCEQ). SIP Modeling Document.
June 2002. Internet address:
http://www.tceq.state.tx.us/assets/public/implementation/air/sip/sipdocs/2002-12-
HGB/tsdpartl.pdf
Topozone. Maps a la Carte, Inc. 2007. Internet address: www.topozone.com
US Census Bureau, 2007. Metropolitan and Micropolitan Statistical Areas. Internet address:
http://www.census.gov/population/www/estimates/metroarea.html
Warneck, 1988. "Chemistry of the Natural Atmosphere." Peter Warneck Academic Press, Inc.
1998.
WRCC, 2006. Western Region Climate Center. Climate Narrative of Each State. Internet
address: http://www.wrcc.dri.edu/CLIMATEDATA.html
34-2
-------
United States Office of Air Quality Planning and Standards Publication No. EPA-454/R-08-001 a
Environmental Protection Air Quality Assessment Division December 2007
Agency Research Triangle Park, NC
------- |