United States Office of Water EPA 815-D-01-002
Environmental Protection 4606 May 2002
Agency
PRA ANALYSIS OF NATIONAL OCCURRENCE OF
trri THE 1998 CONTAMINANT CANDIDATE LIST
(CCL) REGULATORY DETERMINATION
PRIORITY CONTAMINANTS IN PUBLIC
WATER SYSTEMS
Printed on Recycled Paper
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
CONTENTS
TABLES AND FIGURES v
APPENDICES ix
EXECUTIVE SUMMARY xiii
ACKNOWLEDGMENTS xv
DISCLAIMER xvii
I. INTRODUCTION 1
LA. Background 1
I.E. Sources of the Data Used for Analysis 1
I.C. Data Analysis 5
II. URCIS (ROUND 1) DATA OVERVIEW 5
II.A. Description of Data 5
II.B. Data Management and Data Quality 6
II.C. URCIS (Round 1) Data Bias and Representativeness: Further Data Quality
Review and Editing 7
II.D. Data Characteristics Overview 10
III. SDWIS/FED (ROUND 2) DATA OVERVIEW 16
III.A. Description of Data 16
III.B. Data Management and Data Quality 16
III.C. SDWIS/FED (Round 2) Data Bias and Representativeness:
Further Data Quality Review and Editing 17
III.D. Data Characteristics Overview 20
IV NATIONAL INORGANICS AND RADIONUCLIDES SURVEY (MRS) DATA 26
IV A. Description of Data 26
IVB. Representativeness 26
IVC. Data Characteristics Overview 26
IVD. Supplemental IOC Data 29
V DEVELOPING A NATIONALLY REPRESENTATIVE PERSPECTIVE 30
V.A. Methods 31
V.A. 1. Manufacturing Indicators 31
V.A.2. Agricultural Indicators 32
V.B. Representative Cross-Section of States 32
V.B.I. Incremental National Cross-Sections 35
V.B.2. SDWIS/FED (Round 2) 20-State Cross-Section 39
VI. ANALYSIS OF NATIONAL OCCURRENCE 42
VI.A. URCIS (Round 1) Contaminant Occurrence 43
VLB. SDWIS/FED (Round 2) Contaminant Occurrence 43
VI.C. NIRS Contaminant Occurrence 45
VI.D. Comparing Data Coverage of URCIS (Round 1) and SDWIS/FED (Round 2) 46
VI.E. Comparing Across Systems Types and Sizes 49
in
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VII. GRAPHICAL AND SPATIAL ASSESSMENTS OF CCL PRIORITY CONTAMINANTS . . 49
VILA. Aldrin 50
VII.B. Dieldrin 54
VII.C. Metribuzin 57
VII.D. Sulfate 59
VILE. Hexachlorobutadiene 63
VILE Naphthalene 68
REFERENCES 73
IV
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TABLES AND FIGURES
Figure I.B.I. Diagram of the Inter-Relationship of URCIS (Round 1) and SDWIS/FED
(Round 2) Databases, Monitoring Rounds and Contaminant Lists Discussed
in the Report 3
Table I.E. 1. List and Description of CCL Priority Contaminants with Data in URCIS (Round 1)
and SDWIS/FED (Round 2) 4
Table I.B.2. List and Description of the CCL Inorganic Chemicals with data in NIRS 4
Table II.C. 1. Summary of Data Quantity and Quality in URCIS (Round 1) for the States,
Tribes and Territories 8
Table II.D. 1. Data Elements Included in URCIS (Round 1) for UCM (1987) List Contaminants ... 10
Table II.D.2. URCIS (Round 1) Data- Number of Records and Systems by Source Water Type 11
Table II.D.3. URCIS (Round 1) Data- Number of Records and Systems by System Type 11
Table II.D.4. URCIS (Round 1) Data- Number of Records by Year and Source Water Type 12
Table II.D.5. URCIS (Round 1) Data- Number of Records by Month and Source Water Type 12
Table II.D.6. Total Number of Public Water Systems by State and Population Size
Category Contained in the URCIS (Round 1) Database 14
Table II.D.7. Number of Public Water Systems by State, System Type and Population Size
Category Contained in the URCIS (Round 1) Database 15
Table III.C. 1. Summary of Data Quantity and Quality in SDWIS/FED (Round 2) for the
States, Tribes and Territories 18
Table III.D. 1. Data Elements Included in SDWIS/FED (Round 2) for UCM (1993)
List Contaminants 20
Table III.D.2. SDWIS/FED (Round 2) Data - Number of Records and Systems by
Source Water Type 21
Table III.D.3. SDWIS/FED (Round 2) Data- Number of Records and Systems by System Type 22
Table III.D.4. SDWIS/FED (Round 2) Data- Number of Records by Year and Source
Water Type 22
Table III.D.5. SDWIS/FED (Round 2) Data- Number of Records by Month and Source
Water Type 23
Table III.D.6. Total Number of Public Water Systems by State and Population Size
Category Contained in the SDWIS/FED (Round 2) Database 24
Table III.D.7. Number of Public Water Systems by State, System Type and Population
Size Category Contained in the SDWIS/FED (Round 2) Database 25
Table IV.C.l. Data Elements Included in NIRS Database 27
Table IV.C.2. NIRS Data- Number of Records by Year 27
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table IV.C.3. MRS Data- Number of Records by Month 28
Table IV.C.4. Total Number of Public Water Systems by State and Population Size
Category Contained in the NIRS Database 28
Table IV.D. 1. Number of Analyses and Public Water Systems in the 8 Cross-Section
State Data Sets for Manganese and Sodium by Source Water Type 30
Table V.B. 1. Ranking of States based on Number of Manufacturing Establishments per
Square Mile. URCIS (Round 1) 24-State Cross-Section in Bold 33
Figure V.B. 1. Distribution of State Rankings for Manufacturing Establishments / Sq. Mile
vs. Farm Ag. Chemical Expenses. Highlighting URCIS (Round 1)
24 Cross-Section States 34
Figure V.B.2. 24 URCIS (Round 1) Representative Cross-Section States and States
Not Included in the Cross-Section 35
Figure V.B. 1 .a. Distribution of State Rankings for Manufacturing Establishments / Sq. Mile
vs. Farm Ag. Chemical Expenses. URCIS (Round 1) 24-State Representative
Cross-Section Build-up 37
Table V.B. 1 .a. Summary and Comparison of Occurrence Results for Incremental National
Cross-Sections in URCIS (Round 1) 37
Table V.B.l.b. Trichloroethylene Occurrence for the URCIS (Round 1) Cross-Section States
and Comparative Biased Groups of States 39
Table V.B.2.a. Ranking of States based on Number of Manufacturing Establishments per
Square Mile. SDWIS/FED (Round 2) 20 Cross-Section States in Bold 40
Figure VB.2.a. Distribution of State Rankings for Manufacturing Establishments / Sq. Mile
vs. Farm Ag. Chemical Expenses. Highlighting SDWIS/FED (Round 2)
20 Cross-Section States 41
Figure VB.2.b. 20 SDWIS/FED (Round 2) Cross-Section States and States Not Included
in the Cross-Section 42
Table VI.A.l. URCIS (Round 1) Data - 24-State Cross-Section Summary of Occurrence
for CCL Contaminants 43
Table VLB. 1. SDWIS/FED (Round 2) Data - 20-State Cross-Section Summary of
Occurrence for CCL Contaminants 44
Table VI.C.I. NIRS Data - Summary of Occurrence for Priority Contaminants 45
Table VI.D.l. States Common to both URCIS (Round 1) and SDWIS/FED (Round 2) 46
Table VI.D.2. URCIS (Round 1) and SDWIS/FED (Round 2) - Reporting Data in
Comparison of Public Water Systems 48
Figure VII.A.l. Detections of Aldrin - SDWIS/FED (Round 2) Data (including Cross-Section
and non-Cross-Section States) 51
Figure VILA.2. Distribution of Aldrin Occurrence - SDWIS/FED (Round 2) Cross-Section
State Data 52
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Figure VII.A.3. Aldrin Occurrence By Year - SDWIS/FED (Round 2) 53
Figure VII.B.I. Detections of Dieldrin - SDWIS/FED (Round 2) Data (including Cross-Section
and non-Cross-Section States) 54
Figure VII.B.2. Distribution of Dieldrin Occurrence - SDWIS/FED (Round 2) Cross-Section
State Data 55
Figure VII.B.3. Dieldrin Occurrence By Year - SDWIS/FED (Round 2) 56
Figure VII.C.l. Detections of Metribuzin - SDWIS/FED (Round 2) Data (including
Cross-Section and non-Cross-Section States) 57
Figure VII.C.2. Distribution of Metribuzin Occurrence - SDWIS/FED (Round 2)
Cross-Section State Data 58
Figure VII.C.3. Metribuzin Occurrence By Year - SDWIS/FED (Round 2) 59
Figure VII.D.l. Detections of Sulfate - SDWIS/FED (Round 2) Data (including Cross-Section
and non-Cross-Section States) 60
Figure VII.D.2. Distribution of Sulfate Occurrence - SDWIS/FED (Round 2) Cross-Section
State Data 61
Figure VII.D.3. Sulfate Occurrence By Year - SDWIS/FED (Round 2) 62
Figure VII.E.l. States with PWSs with detections of Hexachlorobutadiene for all States
(including Cross-Section and non-Cross-Section States) with data in
URCIS (Round 1) and SDWIS/FED (Round 2) 63
Figure VILE.2. States with PWSs with detections of Hexachlorobutadiene for Round 1
(above) and Round 2 (below) Cross-Section States 64
Figure VII.E.3. Round 1 and Round 2 Cross-Section States with PWSs with
Hexachlorobutadiene detections (upper map) and with concentrations
above the Health Reference Level (lower map) 65
Figure VILE.4. Hexachlorobutadiene Occurrence By Year (1984 - 1997) 66
Figure VILE.5. Occurrence of Hexachlorobutadiene By State - URCIS (Round 1) and
SDWIS/FED (Round 2) 67
Figure VII.F.l. States with PWSs with detections of Naphthalene for all States (including
Cross-Section and non-Cross-Section States) with data in URCIS (Round 1)
and SDWIS/FED (Round 2) 69
Figure VII.F.2. States with PWSs with detections of Naphthalene for Round 1 (above) and
Round 2 (below) Cross-Section States 70
Figure VII.F.3. Round 1 and Round 2 Cross-Section States with PWSs with
Naphthalene detections (upper map) and with concentrations
above the Health Reference Level (lower map) 71
Figure VII.F.4. Naphthalene Occurrence By Year (1984 - 1997) 72
Figure VII.F.5. Occurrence of Naphthalene By State - URCIS (Round 1) and SDWIS/FED (Round 2) 72
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APPENDICES
APPENDIX A. URCIS (Round 1) Data Summary for Two CCL Contaminants: Hexachlorobutadiene
and Naphthalene.
APPENDIX B. SDWIS/FED (Round 2) Data Summary for Six CCL Contaminants: Aldrin, Dieldrin,
Hexachlorobutadiene, Metribuzin, Naphthalene, and Sulfate.
APPENDIX C. NIRS Data Summary for Two CCL Contaminants: Manganese and Sodium.
APPENDIX D. Comparison of URCIS (Round 1) Data to SDWIS/FED (Round 2) Data for Select States
and Select Contaminants
APPENDIX E. Summary Data for URCIS (Round 1) Data and SDWIS/FED (Round 2) Data
for Select Contaminants by System Type and Population Served
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ABBREVIATIONS
Chemical Abstract Services (CAS)
Chemical Monitoring Reform (CMR)
Community Water System (CWS)
Contaminant Candidate List (CCL)
Environmental Protection Agency (EPA)
Ground Water (GW)
Ground Water - Purchased (GWP)
Ground Water Under Direct Influence (GUDI)
Ground Water Under Direct Influence - Purchased (GUP)
Health Reference Level (HRL)
Inorganic Chemical (IOC)
Maximum Contaminant Level (MCL)
Method Detection Limit (MDL)
micrograms per liter ((ig/L)
milligrams per liter (mg/L)
Minimum Reporting Level (or Limit, MRL)
National Contaminant Occurrence Database (NCOD)
National Drinking Water Advisory Council (NDWAC)
National Primary Drinking Water Regulations (NPDWRs)
National Water Quality Assessment Program (NAWQA)
National Inorganic and Radionuclides Survey (NIRS)
Non-Transient Non-Community Water System (NTNCWS)
Office of Ground Water and Drinking Water (OGWDW)
Percentage of Systems with Exceedances (>MCL)
Percentage of Systems with Detections (>MRL)
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
ABBREVIATIONS (continued)
Public Water System (PWS)
Public Water System Identifier (PWSID)
Safe Drinking Water Act (SDWA)
Safe Drinking Water Information System (SDWIS)
Safe Drinking Water Information System/Federal Version (SDWIS/FED)
Surface Water (SW)
Surface Water - Purchased (SWP)
Synthetic Organic Chemical (SOC)
Toxics Release Inventory (TRI)
Transient Non-Community Water System (TNCWS)
United States Geological Survey (USGS)
Unregulated Contaminant Monitoring Information System (URCIS)
Unregulated Contaminant Monitoring (UCM)
Unregulated Contaminant Monitoring Regulation (UCMR)
Volatile Organic Chemical (VOC)
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
EXECUTIVE SUMMARY
This report presents a comprehensive overview of the initial assessment of national occurrence in
public water systems of eight unregulated contaminants on the 1998 Contaminant Candidate List (CCL).
The occurrence findings in this report are based on public drinking water contaminant occurrence data
from the Unregulated Contaminant Information System (URCIS) database, the Safe Drinking Water
Information System/Federal Version (SDWIS/FED) database, and the National Inorganics and
Radionuclides Survey (NIRS). The objective of this study is to provide contaminant occurrence
information in support of their determinations regarding whether regulating specific CCL contaminants
will present a meaningful opportunity to reduce health risk.
This report includes a detailed description of URCIS (Round 1), SDWIS/FED (Round 2), and
NIRS unregulated contaminant monitoring data, identifies and addresses the extensive data quality
management necessary to conduct occurrence analyses, and describes the construction of a national cross-
section of States from URCIS (Round 1) and SDWIS/FED (Round 2). The occurrence analyses of the
eight CCL contaminants are summarized, and spatial and graphical occurrence assessments for specific
contaminants are also presented.
The URCIS database (Round 1 monitoring data) contains public water system monitoring results,
generally from 1988 to 1992, for unregulated contaminants collected under the authority of Safe Drinking
Water Act (SDWA). Forty States/primacy entities have submitted PWS monitoring data to URCIS.
Subsequent Round 2 monitoring data, generally collected from 1993 to 1997, were reported directly to
the SDWIS/FED database. Thirty-five States/primacy entities have submitted Round 2 PWS monitoring
data. The raw data from these two databases were reviewed and edited for data quality considerations to
ensure consistency and repeatability in the analyses. (The analytical results reported here may differ,
therefore, from other analyses using raw data from the first two rounds of unregulated contaminant
monitoring that are contained in the SDWIS/FED database.) The NIRS provides contaminant occurrence
data from 1984 through 1986 from a group of statistically selected, nationally representative public water
systems. These data are from 49 States (there are no data from Hawaii), as well as Puerto Rico. Unlike
the URCIS and SDWIS/FED databases, there are few data quality issues with the NIRS data set.
In contrast to NIRS data (which are by design nationally representative), a data management
approach was used in this study to develop a national cross-section of States from URCIS and
SDWIS/FED. The development of the national cross-sections enabled occurrence analyses that were
indicative of national occurrence using data from these two large databases. All States with monitoring
data were first evaluated by their distribution across a range of pollution potential indicators and
spatial/hydrogeologic diversity. A select group of States, representing a balanced distribution across
these pollution potential measures and across the nation geographically, were then used to construct
national cross-sections (one cross-section from Round 1 data, and another from Round 2 data) that would
provide reasonable representation of national occurrence. While the national cross-sections cannot be
stated to be "statistically representative," the selected cross-sections are very large samples (24 and 20
States, respectively), providing analytical occurrence results that are clear indications of central tendency
of the occurrence data, and are generally indicative of national contaminant occurrence.
Assessments of data coverage and analyses of unregulated contaminant occurrence are also
presented. Comparisons of Round 1 and Round 2 data coverage were made to evaluate if comparable
States, public water systems, and contaminants are contained in both databases. Analytical summaries of
occurrence of the eight contaminants for the Round 1 and Round 2 cross-section States and all NIRS
States are included, such as the percent of public water systems with at least one analytical result greater
than the Minimum Reporting Level (MRL), the percent of public water systems with at least one
analytical result greater than a specified concentration such as Health Reference Level or benchmark
level, and the 99 percentile value. Finally, a detailed graphical and spatial assessment of the
contaminants are developed and presented.
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ACKNOWLEDGMENTS
The compilation and analysis of data presented in this report were undertaken by EPA's Office of
Ground Water and Drinking Water (OGWDW) in support of their determinations regarding whether
regulating specific CCL contaminants will present a meaningful opportunity to reduce health risk. This
effort was directed by Ms. Karen Wirth.
We would like to thank the many States, as well as the American Water Works Service Company,
that contributed data sets and valuable advice. Thanks also to the many public water systems that
conducted the monitoring that provided the contaminant occurrence data used in this report. Mr. Guy
Caruthers and Lewis Summers of OGWDW managed the access to EPA's URCIS and SDWIS/FED
databases, the repositories of data used in this project.
The Cadmus Group, Inc. served as the prime contractor for this project, supporting the data
management, analysis, and report development, under Contract # 68-C-00-113. Dr. George Hallberg
served as the Cadmus Project Manager. The major contributions of Dr. Jonathan Koplos, Erin Hartigan,
and Alison Kotros are gratefully acknowledged.
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
DISCLAIMER
This report does not constitute U.S. Environmental Protection Agency Policy. Mention of trade
names or commercial products does not constitute endorsement or recommendation for use.
This document is designed to provide technical background for the Office of Ground Water and
Drinking Water's program. The document does not, however, substitute for the Safe Drinking Water Act
or EPA's regulations nor is this document a regulation itself. Thus, it cannot impose legally-binding
requirements on EPA, States, or the regulated community, and may not apply to a particular situation
based on the circumstances.
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
I. INTRODUCTION
EPA has determined that there is sufficient information to support a regulatory determination for
a list of eight Contaminant Candidate List (CCL) chemical contaminants: three inorganic contaminants
(manganese, sodium, and sulfate), three synthetic organic contaminants (aldrin, dieldrin, and metribuzin),
and two volatile organic contaminants (hexachlorobutadiene and naphthalene). (Determination on one
microbiological [acanthamoeba] will also be made, but is not addressed in this report.) Based on
contaminant occurrence, exposure, and other risk considerations, EPA must determine if regulating the
CCL contaminants will present a meaningful opportunity to reduce health risk. In this report, national
occurrence data will be analyzed for the eight CCL regulatory determination priority contaminants listed
above.
This report also provides a detailed review of the occurrence data currently available to EPA, and
used in this analysis, which derives from the required monitoring (under the Unregulated Contaminant
Monitoring Regulation) of the "unregulated" contaminants conducted by public drinking water systems.
Currently, there is no complete national record of unregulated or regulated contaminants in drinking water
from public water systems collected under Safe Drinking Water Act (SDWA). Many States have
submitted unregulated contaminant public water system (PWS) monitoring data to EPA, but there are
issues of data quality, completeness, and "representativeness" (how representative the data are of State
occurrence data). Nonetheless, a significant amount of State data are available for contaminants which
can provide estimates of national occurrence.
A two stage analytical approach has been developed for the evaluation of the national occurrence
of these eight CCL contaminants. The first stage of analysis, described in this report, provides a straight-
forward evaluation of occurrence of all the CCL contaminants under consideration. In this Stage 1
Analysis, the data sources, quality, and characteristics are assessed, and the data are used to conduct clear,
simple, and conservative assessments for a broad evaluation of contaminant occurrence. Based on the
findings of the Stage 1 Analysis, EPA can select a set of contaminants for which more detailed and
sophisticated statistical evaluations, the Stage 2 Analysis, may be warranted as a next step to generate
national probability estimates of contaminant occurrence and exposure.
LA. Background
The Safe Drinking Water Act (SDWA), as amended in 1996, requires the United States
Environmental Protection Agency (USEPA) to publish a list of contaminants (referred to as the
Contaminant Candidate List, or CCL) to assist in priority-setting efforts. The contaminants included on
the CCL were not subject to any current or proposed National Primary Drinking Water Regulations
(NPDWR). However, they were known or anticipated to occur in public water systems and were known
or suspected to adversely affect public health, and therefore may require regulation under SDWA.
The 1998 CCL contains 60 contaminants, including 50 chemicals or chemical groups and 10
microbiological contaminants or microbial groups. The SDWA requires the Agency to select five or
more contaminants from the current CCL and determine by August 2001 whether or not to regulate these
contaminants with an NPDWR. Regulatory determinations for at least five contaminants must be
completed 3!/2 years after each new CCL. This report presents contaminant occurrence findings that serve
to support those determinations.
I.B. Sources of the Data Used for Analysis
This section describes the sources of occurrence data used for the analyses in this report.
Occurrence data for most of the contaminants evaluated here (aldrin, dieldrin, hexachlorobutadiene,
metribuzin, naphthalene, and sulfate) are from the Unregulated Contaminant Information System
(URCIS) database and the Safe Drinking Water Information System/Federal version (SDWIS/FED1)
1 SDWIS/FED is the official database repository of data provided by public drinking water systems, and includes data from an earlier EPA
public water system database called the Unregulated Contaminant Information System (URCIS).
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
database. URCIS and SDWIS/FED contain State contaminant occurrence data that were collected and
submitted to EPA.
Extensive data management work was necessary for all data from URCIS and SDWIS/FED used
in this report. The data from these databases used in this report have been reviewed, edited, and filtered
to meet various data quality objectives for the purposes of this analysis. Hence, not all data from a
particular source were used, only data meeting the quality described in later portions of this report. Given
the inherent and significant data quality, completeness, and representativeness issues with the data from
these two databases, detailed discussions regarding data management of URCIS and SDWIS/FED data
are presented in Section II (URCIS Data Overview), Section III (SDWIS/FED Data Overview), and
Section V (Developing A Nationally Representative Perspective). A brief background and clarification of
the contaminants and monitoring periods related to URCIS and SDWIS/FED data is presented below.
The Safe Drinking Water Act (SDWA), as amended in 1986, required public water systems
(PWSs) to monitor for specified unregulated contaminants on a five year cycle, and to report the
monitoring results to the States. Unregulated contaminants do not have an established or proposed
National Primary Drinking Water Regulation (NPDWR), but they are contaminants that were formally
listed and required for monitoring under Federal regulations. The intent was to gather scientific
information on the occurrence of these contaminants to enable a decision regarding whether regulations
were needed. All non-purchased community water systems (CWSs) and non-purchased non-transient
non-community water systems (NTNCWSs), with greater than 150 service connections, were required to
conduct this unregulated contaminant monitoring. Smaller systems were not required to conduct this
monitoring, but were required to be available to monitor if the State decided such monitoring was
necessary. (As evident in the data, many States did collect data from small systems as well.)
The 1993 amendments to SDWA added other contaminants to the unregulated contaminant list
for required monitoring, and the 1996 SDWA amendments directed EPA to develop a revised program for
such monitoring. This new program was formally published in the Federal Register on September 17,
1999 (64 FR 50556), as the Unregulated Contaminant Monitoring Regulation, now referred to as the
UCMR (1999). The UCMR (1999), and related rules, replaced the older requirements, putting forth a
new list of contaminants, a new definition of systems that must monitor, a new structure to the monitoring
program, and a new framework to ensure that all the results are reported to EPA. Monitoring under the
UCMR (1999) will begin in 2001. Every five years this new UCMR must produce a new list of
unregulated contaminants for monitoring. This background and history is reviewed here, in part, because
the terminology, monitoring periods, and lists of monitored contaminants related to the unregulated
contaminant monitoring have often been confusing.
To clarify the history of unregulated contaminant monitoring, a naming system is introduced here
to clearly distinguish between the different monitoring periods and the contaminants included in a
specific monitoring period. In this section of the report, a description is provided of which contaminants
were monitored during which monitoring periods, and which contaminants are included in the different
data sets used. The naming system will follow the convention established for the UCMR (1999), using
the year of promulgation in parenthesis to refer to a specific list of contaminants. For example, the first
unregulated contaminant monitoring list was published in 1987. This specific list of contaminants will be
referred to as the UCM (1987) list. This was followed by the UCM (1993) list, and then by the recent
UCMR (1999) list.
Figure I.B.I diagrams the inter-relationship of the various databases, monitoring rounds and
contaminant lists related to URCIS and SDWIS/FED. Occurrence data for the UCM (1987) and UCM
(1993) contaminants, as well as for other contaminants shown in the following diagram, are contained in
the URCIS and SDWIS/FED databases. These databases are described below.
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure I.B.I. Diagram of the Inter-Relationship of URCIS (Round 1) and SDWIS/FED (Round 2)
Databases, Monitoring Rounds and Contaminant Lists Discussed in the Report
URCIS (Round 1)
(62 Contaminants)
20 Mandatory VOCs (Group 3)
14 Discretionary VOCs (Group 4)
Phase I -21 VOCs
2 Regulated SOCs
5 Miscellaneous Contaminants
SDWIS/FED (Round 2)
(48 Contaminants)
I— 13 SOCs (Group 1)
UCM(1993)-
1 IOC (Group 2)
UCM(1987)
20 Mandatory VOCs (Group 3)
14 Discretionary VOCs (Group 4)
Details of the URCIS database, its contained data, data quantity and quality, etc., are discussed in
Section II. Similar details of the SDWIS/FED database are discussed in Section III.
Table I.B.I presents the list of six CCL regulatory determination contaminants contained in
URCIS (Round 1) and SDWIS/FED (Round 2). This table includes CAS number and SDWIS
contaminant code, and indicates the monitoring Rounds and Group reference numbers for the
contaminants.
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table I.B.I. List and Description of CCL Priority Contaminants with Data in URCIS (Round 1) and
SDWIS/FED (Round 2)
Contaminant
CAS
Number
SDWIS
ID
HRL
(mg/L)
uc
Round
Common Sources of Contaminant
Synthetic Organic Chemicals - Group 1
Aldrin
Dieldrin
Metribuzin
309-00-2
60-57-1
21087-64-9
2356
2070
2595
0.000002
0.000002
0.091
2
2
2
Soil insecticide
Insecticide
Herbicide used on grass and broadleaf weeds
Inorganic Chemicals - Group 2
Sulfate
14808-79-8
1055
500; 1,000
2
Fertilizer, natural occurrence, some industrial
uses
Volatile Organic Chemicals - Group 3
Hexachlorobutadiene
Naphthalene
87-68-3
91-20-3
2246
2248
0.0009
0.14
1
1
2
2
Solvent, synthetic rubber, pesticide, insecticide,
herbicide, chemical intermediate
Fungicide, moth repellant
HRL = Health Reference Level (concentration values used only as reference levels for analyses in this report)
UC Round = data included in Round 1 and/or Round 2 monitoring and database.
Note: Sulfate data were analyzed using two different HRLs.
Data used for analysis of the remaining inorganic contaminants (manganese, and sodium) are
from the National Inorganics and Radionuclides Survey (NIRS) database. The NIRS data, collected for a
statistically designed, nationally representative survey, can be used directly for national contaminant
occurrence analyses with very few, if any, data quality or use issues. One limitation, however, is that the
NIRS data are from groundwater systems only. The NIRS data, and assessments of supplemental IOC
data, are discussed in Section IV (NIRS Data Overview).
The NIRS survey was designed and conducted by EPA specifically to provide data on the
occurrence of a select set of radionuclides and inorganic chemicals (lOCs) being considered for National
Primary Drinking Water Regulations. The NIRS provides contaminant occurrence data from
approximately 989 nationally representative community public water systems served by ground water.
(NIRS does not include surface water systems.) Each of these statistically randomly selected public water
systems was sampled a single time between 1984 and 1986. Table I.B.2 describes the NIRS inorganic
contaminants for which occurrence was assessed in this report.
Table I.B.2. List and Description of the CCL Inorganic Chemicals with data in NIRS
Contaminant
CAS
Number
SDWIS
ID
HRL1
(mg/L)
Common Sources of Contaminant
Inorganic Chemicals - Group 2
Manganese
Sodium
7439-96-5
7440-23-5
1032
1052
0.05; 0.30
30; 120
Naturally occurring, manganese compounds produced in
many industrial processes
Naturally occurring, widely used in table salt, road salt,
additives to buffer or to soften drinking water
1. In the case of sodium, a benchmark, rather than an HRL, was chosen based on taste thresholds and effects, which occur at lower
concentrations than health effects.
HRL = Health Reference Level (concentration values used only as reference levels for analyses in this report)
Note: Manganese data were analyzed using two different HRLs. Sodium data were analyzed using two different benchmark levels.
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
I.C. Data Analysis
All statistical analyses, and most database manipulations, were conducted with SAS® statistical
software. Some data formatting problems were corrected in Microsoft® Excel with the aid of specialized
programs written in Visual Basic or were corrected directly in SAS before the analysis began After
analysis, results were typically exported into Excel for secondary analysis, sorting, or the development of
report tables.
This report contains summary data analyses, using data from three databases, that serve as the
basis of this Stage 1 contaminant occurrence analysis. These summary analyses identify data coverage,
highlight and address data quality issues encountered in the raw data, establish basic data quality, and
provide an initial assessment of occurrence of eight CCL contaminants in public water systems.
II. URCIS (ROUND 1) DATA OVERVIEW
In this section of the report, the monitoring results for the URCIS (Round 1) data (from
approximately 1988-1992) are reviewed. The data (as described in Section I) were derived from EPA's
Unregulated Contaminant Information System (URCIS) database.
II.A. Description of Data
URCIS is a compilation of public water system monitoring results for unregulated contaminants,
collected under the authority of SDWA, and reported to the States (as the primacy agents for SDWA).
EPA requested that the States submit these data to EPA in the early 1990s, but no formal protocol or
format had been established for reporting. Given the evolving nature of data management during this era
various problems were encountered. The data were supplied by States on a variety of media, ranging
from photocopies of hand-written files to electronic files on magnetic tape or diskettes of various kinds,
and in many different formats and software configurations. Some data were electronically transferrable,
other data had to be manually entered or re-entered. EPA has been working on the clean-up and analysis
of these data since 1992. Through this long history3, many critical data quality problems were resolved
(such as getting the data into consistent, standard units of measure), or at least resolved to the extent
possible.
Some preliminary analyses of the URCIS (Round 1) data were presented in the occurrence data
report produced for EPA-OGWDW's Chemical Monitoring Revisions (CMR) project. This report, A
Review of Contaminant Occurrence in Public Water Systems (USEPA, 1999), is referred to as the "CMR
Report". In 1999, EPA also transferred the URCIS data into SDWIS/FED, in an attempt to join the
URCIS (Round 1) data with Round 2 data being submitted by the States into SDWIS/FED. Some
preliminary analyses of these joined data were performed4. Because of various software and database
complications, the transfer of the URCIS (Round 1) data into SDWIS/FED was not complete, creating
problems in the resultant analysis undertaken in the previous work. Later, during the initial analyses of
this current report, various data quality problems in the SDWIS/FED-derived URCIS database itself were
identified, particularly in the units of measure of the recorded analytical results. Hence, for the analysis
presented in this report, the original URCIS database was evaluated.
2 SAS is a registered trademark of the SAS Institute, Inc. Excel and Visual Basic are trademarks of the Microsoft Corporation.
3 For example, Fallen, Fran, 1994 (November), "Unregulated Contaminants Information System (URCIS) System Inventory." Computer
Sciences Corp, 1993 (March), "Unregulated Contaminants Maintenance Manual." Fallen, Fran, 1993 (December), "Unregulated Contaminants
Maintenance Manual Supplement." Computer Sciences Corp, 1992 (July), "A Statistical Survey of the Unregulated Contaminant Data." (All of
these internal reports contain many pages of text, sometimes unnumbered, and typically many pages of unnumbered tabulated data and/or
computer code.)
4 SAIC, 1999 (June), "Unregulated Contaminant Occurrence Results for Round One Monitoring," SAIC Project 01-0833-08-3559-030. EPA
Contract 68-C6-0059.
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
The version of URCIS used as the basis for this analysis was the complete and most current
(1997) edition of this EPA Office of Ground Water and Drinking Water database. The original, raw
edition of the database was edited for data quality considerations, as described below, to ensure
consistency and repeatability in the analyses. The values reported here from URCIS may be somewhat
different than in other EPA reviews (or the CMR report) because of the screening and editing conducted
specifically for this study to ensure consistency in and dependability of the analyses.
The URCIS database (as noted in Section I) includes information on 62 contaminants, including:
34 unregulated VOCs; 2 regulated SOCs and 21 regulated VOCs; and 5 miscellaneous contaminants
reported by the States. The data were reported from 38 States, Washington, B.C., and the Virgin Islands.
The data are from the first round of required unregulated contaminant monitoring initiated in 1987 (i.e.,
UCM (1987)), but also include older data that are comparable to, but predate, the formal beginning of
first round monitoring.
II.B. Data Management and Data Quality
During 1997-1998, the URCIS database was reviewed for various data quality problems and
subsequently edited to remove problematic data to ensure the quality of the data used in the analysis. The
data were first downloaded from the URCIS database. In the process of initial download and translation,
unreadable lines of text and characters were apparently introduced into the data set and were therefore
deleted. (These lines did not appear to be actual data, but were artifacts related to download, translation,
and merger of various data sets from URCIS.) Additionally, data from 946 systems of unknown source
water type were eliminated. (Other systems had no source type specified, but this missing inventory
information was supplemented with SDWIS inventory data.) Five observations with contaminant
concentrations greater than 9,000 micrograms/Liter and were excluded from the analysis (as presumed
errors; this outlier editing was consistent with other processing that EPA has completed, see USEPA,
1999). Another 1,503 observations with erroneous sampling dates (e.g., years indicated as 00, 01, 39,
etc.) were eliminated.
Some sample identification numbers from six States were missing required digits (they had an
inadequate number of sample ID numbers to define a unique sample, as compared to other sample IDs).
New sample numbers were assigned by concatenating the system ID with the original sample ID so that a
given sample number was unique and could not appear more than once in the database. Also, the
analyses noted that some data from 357 systems were sometimes identified as ground water systems and
at other times as surface water systems. These records were presumably from systems with mixed water
sources. The inclusion of these data result in a very slight overcount of systems (when totaled by source
water type), but these mixed source results comprise only a very small amount of data.
Some further editing was performed for this current analysis. Some URCIS (Round 1) analytical
results included unidentified contaminant codes. These data were merged with a list of contaminants
based on the Chemical Abstract Services (CAS) number to identify the chemical name. Five contaminant
codes used in URCIS (Round 1), totaling 22,548 records, did not match any contaminants on the CAS
list. These records were removed from the database to ensure quality of analysis. Systems with a system
type recorded as "NP", i.e., non-public, were also removed, because it is unclear what this designation
means regarding type(s) of system. Also, some data were included in the original URCIS database that
date from the first three months of 1993. The inclusion of 1993 data was not consistent among States,
some States included only partial records, and 1993 data are also included in Round 2. Hence, for
consistency, the samples recorded after 1992 (14,221 observations) were removed from the URCIS
database prior to analysis.
For some records, the data were of good quality, but some system inventory information was
missing. To enable use of these URCIS (Round 1) data records, the URCIS (Round 1) data were merged
by PWSID with current SDWIS-Needs Survey PWS Inventory data to obtain missing system inventory
information data on the source water, system type and population served for the PWSs. Note that these
supplemental inventory data are from 1999. While URCIS (Round 1) data are from an earlier period, the
inventory provided a consistent data source to update the information. After these data management and
editing efforts, there are 3,452,530 analytical records for the 62 contaminants in URCIS (Round 1).
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Even with this extensive data management effort, there will still be data quality problems given
the diverse sources of these data and the sheer size of the database (i.e., 3.5 million records). Sources of
problems may include some data recorded in incorrect units, (e.g., the results are actually in mg/L, but are
recorded as (ig/L) or data units mistakenly converted in the original compilation of the data (e.g., the data
units were actually in (ig/L, were incorrectly assumed to be in mg/L, and were then mistakenly
'converted' to (ig/L as if they were mg/L). Recent reviews of the original database indicate that this does
not appear to affect many data. There are a few abnormally high analytical results (outliers) that may be
affected by this units problem. While outliers affect a review of the maximum concentration values of a
contaminant, there are few such data and they will have limited impact on other occurrence statistics
reviewed in this report. (For most analytical summaries included in this report, the value of the 99th
percentile is presented to avoid this problem.)
II.C. URCIS (Round 1) Data Bias and Representativeness: Further Data Quality Review and
Editing
Subsequent to the major editing efforts on this database, a basic analysis of the 3.5 million
records was undertaken. As a first step, various descriptive statistics were compiled by State to enable a
further data review for bias and representativeness. Some State data, as will be described, are so
incomplete that their use would introduce bias into the analyses. This was an important factor of the data
quality assessment when reviewing data to determine whether they can be used for Stage 2 analysis.
These data are used in certain parts of this report to provide context or reference, but not to make
determinations based on their occurrence analyses.
Table II.C. 1 summarizes some key results from this next stage of data review. The table
summarizes the data availability for 57 primacy entities considered under SDWA: the 50 States, 5
territories, the District of Columbia, and an aggregate entry for the Native American tribes. Within
URCIS (Round 1), there are data for 38 States, the Virgin Islands, and Washington, D.C., and no data for
17 primacy entities. Some States only reported data for detections. For eight States (listed in the column
labeled "Data sets with 100% Detects"), the percent of samples with analytical detections (or in other
words, the percent of samples with analytical results greater than the Minimum Reporting Level, labeled
in the tables as "Percent Sample Detections") ranged from 80-100%. These States only reported data for
detections and, hence, are highly biased (they did not report the majority of the monitoring sample results
for which there were no detections above the MRL). As presented in the table, the percent of samples
with detections (aggregating all the data), typically ranges from 1-3% for States with complete data
reporting. Besides this obvious source of bias, the apparent completeness of the data related to the
number of PWSs represented is also reviewed.
The number of unique PWSs included in each State's data record is shown in Table II.C. 1. The
number of PWSs included were compared to the total number of nonpurchased CWSs and NTNCWSs in
the current State inventory, and to the number of nonpurchased CWSs and NTNCWSs serving more than
500 people (since not all small systems may have had to conduct this monitoring). The States listed as
"Most Complete Data sets" all approximated or exceeded 100% of one of these numbers (i.e., New
Mexico's URCIS (Round 1) PWS numbers were only 70% of their current total inventory, but equaled
300% of the number of systems serving more than 500 persons). The States listed as "Significantly Too
Few Systems" had far less representativeness. For example, Colorado only has data in URCIS (Round 1)
for 60 PWSs. This represents only 24% of the reported number of systems in their inventory lists. Also,
Colorado data show 34% of all sample data are detections. Further review suggests that their data mainly
include records for systems that had detections, but that analytical records were provided for all samples
for these systems. This partial, selective reporting lowers the percent of sample records that represent
detections (to less than 100% detection), but still reflects biased reporting and creates a biased analytical
record, since not all non-detection records have been reported (such as records from the likely large
number of systems with non-detections). In other cases, it is not clear what the data represent. Nevada's
reported percent samples with detections suggests the data may be complete, but there is only data for 10
systems, only about 3% of systems as based on State inventory records. Another five States are listed as
having too few systems.
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table II.C. 1 also presents the number of samples per PWS in each State's data. This summary
statistic provides a perspective on the relative completeness of reporting. For example, the States
reporting only samples with detections typically report 2 to 10 samples per PWS. For most States,
approximately 100 to 300 samples are collected and reported per PWS.
The last column on Table II.C. 1 lists States with data records that are not complete (i.e., less than
100% of systems reported as based on inventory listings), but that have other parameters (e.g., "Percent
Sample Detections", "Samples per PWS", etc.) that suggest that the data are balanced and perhaps
complete for the systems that did report. The relatively low system numbers may simply relate to how
the State implemented the program (e.g., implementation related to system size or other waivers, etc.).
Florida reports data for 855 PWSs, a substantive number, but they also have a large inventory.
Table II.C.l. Summary of Data Quantity and Quality in URCIS (Round 1) for the States, Tribes and
Territories
States/ Tribes/
Territories
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
Alabama
Alaska
American Samoa
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
Florida
Georgia
Guam
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Marianna Islands
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
Total
Unique
PWSs
152
748
-
973
6
4,167
60
-
13
855
1,165
-
127
-
1,307
415
1,002
-
525
13
-
-
998
220
139
1,565
206
85
565
214
10
201
1,551
617
357
298
Percent
Sample
Detections
5%
2%
1%
100%
7%
34%
6%
20%
2%
1%
5%
4%
5%
3%
3%
2%
91%
100%
1%
100%
1%
2%
100%
2%
100%
2%
0%
1%
2%
Samples
per PWS
136
132
151
5
111
38
1,207
14
120
370
147
292
62
273
95
105
14
16
100
6
215
94
6
860
5
94
151
348
134
No Data in
Database
American Samoa
Connecticut
Guam
Idaho
Kansas
Maine
Marianna Islands
Data sets with
100% Detects
Arkansas
Massachusetts
Michigan
Mississippi
Nebraska
New Hampshire
Significantly
Too Few
Systems
Colorado
Delaware
Louisiana
Missouri
Nevada
States Usable for Cross-Section
Most Complete
Data Sets
Alaska
Arizona
California
Georgia
Hawaii
Illinois
Indiana
Iowa
Kentucky
Maryland
Minnesota
Montana
New Jersey
New Mexico
Incomplete but
Adequate Data
sets
Alabama
Florida
New York
North Carolina
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
States/ Tribes/
Territories
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Puerto Rico
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Tribes
Utah
Vermont
Virgin Islands
Virginia
Washington
Washington, D.C.
West Virginia
Wisconsin
Wyoming
TOTAL
Total
Unique
PWSs
-
2,657
-
-
-
-
-
335
306
124
430
133
3
-
992
1
139
-
145
23,819
Percent
Sample
Detections
1%
4%
4%
98%
1%
82%
9%
1%
5%
6%
3%
2.9%
Samples
per PWS
313
52
197
2
150
10
186
229
3,432
157
125
146
No Data in
Database
North Dakota
Oklahoma
Oregon
Pennsylvania
Puerto Rico
Rhode Island
South Carolina
Tribes
Virginia
Wisconsin
17
Data sets with
100% Detects
Texas
Vermont
8
Significantly
Too Few
Systems
5
States Usable for Cross-Section
Most Complete
Data Sets
Ohio
South Dakota
Tennessee
Utah
Washington
Washington, D.C.
Wyoming
21
Incomplete but
Adequate Data
sets
Virgin Islands
West Virginia
6
In summary, of the 40 States/territories with data in URCIS (Round 1), 21 States have records
that appear relatively complete and balanced, and another 6 have records that likely are balanced and with
a substantial (though not complete) number of systems. The data from these 27 States should provide the
most complete and unbiased summary of the occurrence data; the remaining 13 States are clearly biased
since results are reported only (or primarily) for detections. To present a national summary of the data,
the 27 primacy entities with most complete records (the 27 States identified in the two far-right columns
in Table II.C.I, "Most Complete Data Sets," and "Incomplete but Adequate,") were evaluated for their
national representativeness and considered for inclusion in the subsequent analyses. (The assessment of
national representativeness is discussed further in Section IV.)
From these 27 States with reasonably complete data, three primacy entities were removed.
Washington, D.C. and the Virgin Islands were removed because they are not States, and the New York
State data were excluded because there were various and numerous problems associated with the data and
metadata. For example, New York did not use standard PWSIDs that could be associated with SDWIS
records, and the total number of reporting PWSs in the New York data set represented only 12 to 40% of
the expected number of PWSs as based on the State's inventory numbers. Also, there were some
embedded errors in the data that sometimes caused data processing problems. Therefore, as summarized
in Section VI, data are aggregated for a representative cross-section of 24 States (the 27 entities less
Washington, D.C., the Virgin Islands, and New York), as well as for all 40 entities (which includes all
entities; those with complete and balanced records, as well as the entities with biased records).
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
II.D. Data Characteristics Overview
A descriptive overview of the data is presented in a series of tables to provide additional insight
and perspective on the results. After data management and editing, 3.45 million records were available
for analysis representing over 24,000 PWSs from the 40 States/entities. For the 24 States comprising the
URCIS (Round 1) representative cross-section (see Section VI for a discussion regarding cross-section),
the analytical results total is 3.27 million records, from 22,034 PWSs. Summary results for all States, as
well as for the 24 cross-section States, are included in the following tables.
Table II.D.l shows data elements included in URCIS (Round 1). Note that a special data element
was developed in URCIS (Round 1) to distinguish between a detection and a result below the minimum
reporting level. (Many States do not provide an actual value for the minimum reporting level, or MRL,
and often these values are recorded as a zero in the analytical result field.)
Table II.D.l. Data Elements Included in URCIS (Round 1) for UCM (1987) List Contaminants
Data Element
PWS Identification Number
Source Identification Number
Source Water Type
Ground Water
Surface Water
Chemical Abstract Services (CAS) Number
Contaminant Name
Contaminant Group
SOC
VOC
Y
Sample Date
Analysis Result
Detection Identifier
0
1
Community Type
CWS
NCWS
NTNCWS
Population Served
Description
Nine digit identification number unique to each public
water system
Three-digit code to identify the source
Ground water or purchased ground water
Surface water, purchased surface water, ground water under the direct influence of surface
water or purchased ground water under the direct influence of surface water
Unique numeric designation used to identify specific c
liemical compounds
Commonly used contaminant name
Synthetic Organic Chemicals
Volatile Organic Chemicals
Trihalomethanes
Date sample was collected (years 1983 through 1992)
Concentration of the sample (measured in micrograms
liter)
Code to determine if analysis result is greater than or less than the Minimum Reporting
Result is less than the Minimum Reporting Level
Result is greater than the Minimum Reporting Level
Community Water System
Non-Community (Transient) Water System
Non- Transient Non-Community Water System
Population served by the public water system
Included in Table II.D.2 are the number and percent of sample records and systems related to
source water type: 87% of the systems are classified as ground water and 13% as using surface water.
The Round 1 data were collected before "ground water under the direct influence of surface water"
(GUDI) was introduced as a source definition. The classification used follows the regulatory guidelines:
if a system uses any surface water, the system is classified, and is required to monitor, as a surface water
system.
10
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table II.D.2. URCIS (Round 1) Data- Number of Records and Systems by Source Water Type
SOURCE TYPE
Total - Ground Water
Total - Surface Water
Total
24 States - Ground Water
24 States - Surface Water
24 States - Total
RECORDS
NUMBER
2,950,618
501,912
3,452,530
2,814,472
453,173
3,267,645
PERCENT
85.5%
14.5%
100.0%
86.1%
13.9%
100.0%
SYSTEMS
NUMBER
21,046
3,130
24,176
19,637
2,695
22,332
PERCENT
87.1%
12.9%
100.0%
87.9%
12.1%
100.0%
Note: There are a greater number of "Total" and "24 States Total" systems here than in Table II.D.3 since some water systems have more than
one source water type.
Table II.D.3. shows the number and percent of records and systems by system type. About 7%
of systems were coded as "NCWS", a SDWIS code typically used for transient systems. Transient PWSs
were not required by federal rule to monitor, but may have been required to by some States. Also, about
7% of the systems did not indicate a system type (and the type could not be determined by SDWIS
inventory records). These data remained in the database for the first stages of analysis, because other data
elements were complete.
Table II.D.3. URCIS (Round 1) Data- Number of Records and Systems by System Type
SYSTEM TYPE
Total - CWS1
Total - NCWS2
Total - NTNCWS3
Total - UNKNOWN
Total
24 States - CWS1
24 States - NCWS2
24 States - NTNCWS3
24 States - UNKNOWN
24 States - Total
RECORDS
NUMBER
2,608,840
89,707
516,047
237,936
3,452,530
2,546,144
89,533
515,807
116,161
3,267,645
PERCENT
75.6%
2.6%
14.9%
6.9%
100.0%
77.9%
2.7%
15.8%
3.6%
100.0%
SYSTEMS
NUMBER
15,562
1,771
4,872
1,614
23,819
14,260
1,746
4,774
1,254
22,034
PERCENT
65.3%
7.4%
20.5%
6.8%
100.0%
64.7%
7.9%
21.7%
5.7%
100.0%
1. CWS = Community Water System
2. NCWS = Non-Community (Transient) Water System
3. NTNCWS = Non-Transient Non-Community Water System
Note: There are a fewer number of "Total" and "24 States Total" systems here than in Table II.D.2 since some water systems have more than one
source water type.
Tables II.D.4 and II.D.5 show the distribution of data by years and by month across all years.
The majority of data were collected during the 1987-1992 compliance cycle, with a peak of data
collection in 1991. (Records prior to 1987 predate the formal beginning of first round monitoring, but
represent comparable data, and are therefore included to expand the coverage of these analyses.)
Although in the month of March there is a slightly greater monthly percentage of data, there is no
significant difference, suggesting that there should be no seasonal bias due to monthly differences in
reporting.
11
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table II.D.4. URCIS (Round 1) Data- Number of Records by Year and Source Water Type
YEAR
Total -1983
Total -1984
Total -1985
Total -1986
Total -1987
Total -1988
Total -1989
Total -1990
Total -1991
Total -1992
TOTAL
24 States -1983
24 States -1984
24 States -1985
24 States -1986
24 States -1987
24 States -1988
24 States -1989
24 States- 1990
24 States -1991
24 States -1992
24 States - TOTAL
# SURFACE
WATER
RECORDS
260
150
233
1,939
12,942
119,367
131,030
101,945
108,681
25,365
501,912
0
30
175
1,852
12,876
107,428
111,979
87,273
106,338
25,222
453,173
# GROUND
WATER
RECORDS
553
44,305
78,994
140,620
120,728
232,471
382,077
574,609
1,179,423
196,838
2,950,618
5
43,837
78,696
140,155
120,292
214,190
337,068
509,889
1,174,459
195,881
2,814,472
TOTAL #
RECORDS
813
44,455
79,227
142,559
133,670
351,838
513,107
676,554
1,288,104
222,203
3,452,530
5
43,867
78,871
142,007
133,168
321,618
449,047
597,162
1,280,797
221,103
3,267,645
% OF TOTAL
RECORDS
0.0%
1.3%
2.3%
4.1%
3.9%
10.2%
14.9%
19.6%
37.3%
6.4%
100.0%
0.0%
1.3%
2.4%
4.3%
4.1%
9.8%
13.7%
18.3%
39.2%
6.8%
100.0%
Table II.D.5. URCIS (Round 1) Data- Number of Records by Month and Source Water Type
MONTH
Total - January
Total - February
Total - March
Total - April
Total - May
Total - June
Total - July
Total - August
Total - September
Total - October
# SURFACE
WATER
RECORDS
35,587
47,287
50,360
35,705
49,007
44,784
33,777
43,397
38,699
38,267
# GROUND
WATER
RECORDS
276,606
267,434
345,113
272,149
267,254
207,553
197,418
196,703
223,775
232,324
TOTAL # OF
RECORDS
312,193
314,721
395,473
307,854
316,261
252,337
231,195
240,100
262,474
270,591
% OF TOTAL
RECORDS
9.0%
9.1%
11.5%
8.9%
9.2%
7.3%
6.7%
7.0%
7.6%
7.8%
12
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
MONTH
Total - November
Total - December
Total
24 States - January
24 States - February
24 States - March
24 States - April
24 States - May
24 States - June
24 States - July
24 States - August
24 States - September
24 States - October
24 States - November
24 States - December
24 States - Total
# SURFACE
WATER
RECORDS
41,990
43,052
501,912
33,315
42,774
42,903
33,625
45,221
38,140
31,060
40,967
33,214
35,756
39,480
36,718
453,173
# GROUND
WATER
RECORDS
225,235
239,054
2,950,618
266,685
259,528
328,589
262,270
254,900
190,791
190,254
185,958
209,679
222,984
215,372
227,462
2,814,472
TOTAL # OF
RECORDS
267,225
282,106
3,452,530
300,000
302,302
371,492
295,895
300,121
228,931
221,314
226,925
242,893
258,740
254,852
264,180
3,267,645
% OF TOTAL
RECORDS
7.7%
8.2%
100.0%
9.2%
9.3%
11.4%
9.1%
9.2%
7.0%
6.8%
6.9%
7.4%
7.9%
7.8%
8.1%
100.0%
Table II.D.6 summarizes the number of systems and population served for each State by
population-served size categories. Table II.D.7 provides further details by system type. Note that the
majority of New York and Alaska systems cannot be associated with a population-served because the
population data were not reported, and for the URCIS (Round 1) data these States used State-specific
PWSIDs systems that cannot be supplemented by other databases. (We were not able, for example, to
derive population estimates for systems by merging the URCIS (Round 1) data to New York or Alaska
State data in SDWIS because of the lack of common PWSIDs.) Also, while California has a large
number of systems without population data (540), this only constitutes about 13% of the systems
represented in their data.
The analytical findings of the occurrence data for the two CCL contaminants (naphthalene and
hexachlorobutadiene) from the 24 URCIS (Round 1) cross-section States are developed and summarized
in Section VI of this report.
13
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table II.D.6. Total Number of Public Water Systems by State and Population Size Category Contained in the URCIS (Round 1) Database
State
Alaska
Alabama
Arkansas
Arizona
California
Colorado
Washineton.D.C.
Delaware
Florida
Georaia
Hawaii
Iowa
Illinois
Indiana
Kentucky
Louisiana
Massachusetts
Maryland
Michiaan
Minnesota
Missouri
Mississippi
Montana
North Carolina
Nebraska
New Hampshire
New Jersey
New Mexico
Nevada
New York
Ohio
South Dakota
Tennessee
Texas
Utah
Virsin Islands
Vermont
Washinston
West Virainia
Wvomina
TOTAL
24 States
<500
Systems
54
33
1
665
2,520
37
1
0
434
788
51
549
624
146
267
1
12
720
52
1.131
1
62
470
177
117
125
1.210
453
0
1
1,852
225
65
26
253
0
83
574
15
89
13,884
13.365
Pop.
1.914
7.009
200
102.991
317.235
5,204
0
0
72.950
117.453
11.477
106.710
122.394
25.846
47.385
400
1.555
106.915
8.803
128.066
25
16.421
64.429
29.818
24.264
18.040
142.718
66.407
0
380
289.842
36.254
11,205
6.449
47.854
0
13.443
118.291
2.337
19.296
2,091,980
1.996.796
501-3,300
Systems
0
27
3
218
559
9
0
2
193
231
40
356
459
160
117
1
25
201
47
315
6
92
69
62
73
47
223
116
0
5
555
83
85
49
95
1
35
266
81
35
4,941
4.546
Pop.
0
55.027
3.735
270.754
782.402
13,047
0
2.434
281.349
310.920
61.169
432.396
586.283
222.855
182.427
3.300
58.716
228.018
74.381
422.736
18.503
134.099
92.750
104.598
87.124
67.207
265.866
142.048
0
7.000
675.965
102.550
128,990
69.308
142.188
2.000
53.217
381.713
131.115
49.438
6,647,628
6.053.557
3,301-10,000
Systems
0
41
-)
50
211
2
0
6
88
84
97
69
135
61
76
6
60
49
17
61
50
29
19
33
14
13
54
26
7
1
120
16
85
26
41
0
9
72
28
13
1,696
1.454
Pop.
0
240.441
11.928
271.132
1.349.634
13,600
0
32.198
525.826
473.277
127.092
400.312
768.046
346.289
453.476
33.705
394.623
256.062
100.965
341.983
296.997
166.067
104.176
202.185
78.871
77.742
335.843
168.031
43,850
3,500
713,602
81,272
539,009
135.427
253.727
0
53.070
430.502
156.505
77.875
10,058,840
8.616.297
10,001-50,000
Systems
0
41
0
30
212
8
0
2
100
46
11
20
76
39
61
3
97
22
17
54
24
22
5
23
8
14
50
19
1
1
102
9
59
13
29
9
5
57
13
6
1,301
1.084
Pop.
0
784.624
0
663.184
5.498.165
162,546
0
60.300
2.393.159
1.056.758
240.632
444.462
1.551.040
856.829
1.239.827
65.310
2.281.386
494.978
382.481
1.264.645
382.805
551.708
146.666
493.108
176.145
261.331
1.167.427
450.299
27,060
17,000
2,149,959
134,818
1,314,876
231.413
656.592
64.000
105.300
1.338.993
300.335
116.923
29,527,084
24.758.299
>50,000
Systems
0
10
0
10
125
4
0
3
38
16
3
8
13
9
4
2
16
6
6
2
3
1
0
3
-)
2
14
3
o
0
26
-)
12
10
12
0
1
9
2
0
383
331
Pop.
0
1.705.098
0
2.705.523
20.801.367
1,680,200
0
404.800
6.326.159
2.967.369
820.233
744.541
4.215.097
1.660.931
1.224.025
137.400
3.060.031
3.765.001
1.634.269
146.335
191.700
205.895
141.151
283.900
580.341
184.750
3.572.618
545.179
1,000,000
0
4,916,684
155,814
1,921,707
2.317.678
2.017.135
0
56.000
1.531.541
238.577
109.000
73,968,049
62.514.985
SYSTEMS
WITH POP
DATA
54
152
6
973
3.627
60
1
13
853
1.165
127
1.002
1.307
415
525
13
210
998
139
1.563
84
206
565
298
214
201
1.551
617
10
8
2.655
335
306
124
430
3
133
978
139
145
22,205
20.780
SYSTEMS
WITH NO
POP DATA1
694
0
0
0
540
0
0
0
2
0
0
0
0
0
0
0
10
0
0
2
1
0
0
0
0
0
0
0
0
349
2
0
0
0
0
0
0
14
0
0
1,614
1.254
TOTAL
Systems
748
152
6
973
4.167
60
1
13
855
1.165
127
1.002
1.307
415
525
13
220
998
139
1.565
85
206
565
298
214
201
1.551
617
10
357
2.657
335
306
124
430
3
133
992
139
145
23,819
22.034
Pop. Served
1.914
2.792.199
15.863
4.013.584
28.748.803
1,874,597
0
499.732
9.599.443
4.925.777
1.260.603
2.128.421
7.242.860
3.112.750
3.147.140
240.115
5.796.311
4.850.974
2.200.899
2.303.765
890.030
1.074.190
549.172
1.113.609
946.745
609.070
5.484.472
1.371.964
1,070,910
27,880
8,746,052
510,708
3,915,787
2.760.275
3.117.496
66.000
281.030
3.801.040
828.869
372.532
122,293,581
103.939.934
1. A total of 1,614 systems in the UCM (1987) database do not contain population-served information. Population-served information was also not available for those systems in the 1999 Needs
Survey, and therefore, the population size categories could not be determined for these systems.
Note: The total number of systems is different from the totals in Table IV.A.2 since some systems have more than one source type.
14
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table II.D.7. Number of Public Water Systems by State, System Type and Population Size Category Contained in the URCIS (Round 1) Database
State
Alaska
Alabama
Arkansas
Arizona
California
Colorado
Washington.D.C.
Delaware
Florida
Georgia
Hawaii
Iowa
Illinois
Indiana
Kentucky
Louisiana
Massachusetts
Maryland
Michigan
Minnesota
Missouri
Mississippi
Montana
North Carolina
Nebraska
New Hampshire
New Jersey
New Mexico
Nevada
New York
Ohio
South Dakota
Tennessee
Texas
Utah
Virgin Islands
Vermont
Washington
West Virginia
Wyoming
TOTAL
24 States
Pooulation Size Category (Population Served bv System!
<500
TOTAL
54
33
1
665
2.520
37
1
434
788
51
549
624
146
267
1
12
720
52
1,131
1
62
470
177
117
125
1.210
453
1
1.852
225
65
26
253
83
574
15
89
13,884
13.365
System Tvr
CWS1
9
12
1
387
1.491
28
1
384
644
41
439
624
51
101
1
6
323
51
444
1
53
324
168
91
90
123
355
1
703
197
24
21
181
72
558
13
79
8,092
7.675
NTNCW
2
21
133
321
8
18
133
7
94
89
160
3
388
582
9
114
9
21
29
800
95
971
25
35
4
54
4
6
0
8
4,145
4.067
e
NCWS3
43
145
708
1
32
11
3
16
6
6
3
9
1
105
32
5
6
287
3
178
3
6
1
18
7
10
2
1,647
1.623
501 - 3,300
27
3
218
559
9
2
193
231
40
356
459
160
117
1
25
201
47
315
6
92
69
62
73
47
223
116
5
555
83
85
49
95
1
35
266
81
35
4,941
4.546
Svstem Tvr
CWS1
20
3
169
422
8
2
187
205
35
338
459
152
91
1
24
109
46
295
6
86
63
62
71
45
69
95
5
354
82
75
46
90
1
32
264
79
34
4,125
3.749
NTNCW
7
40
70
1
4
25
3
16
8
25
1
92
1
19
6
6
2
2
145
21
183
1
10
3
5
3
2
2
1
704
685
e
NCWS3
9
67
2
1
0
2
1
1
9
18
112
112
3,301 - 10,000
41
2
50
211
2
6
88
84
22
69
135
61
76
6
60
49
17
61
50
29
19
33
14
13
54
26
7
1
120
16
85
26
41
9
72
28
13
1696
1454
Svstem Tvr
CWS1
41
-)
47
196
-)
6
88
83
22
69
135
61
76
6
60
48
16
60
50
28
19
33
14
13
52
26
7
1
117
15
85
26
41
9
72
28
13
1667
1427
NTNCW
3
7
1
1
1
1
2
2
18
17
e
NCWS3
8
1
1
1
11
10
10,001 - 50,000
41
30
212
8
2
100
46
11
20
76
39
61
3
97
77
17
54
24
77
5
23
8
14
50
19
1
1
102
9
59
13
29
2
5
57
13
6
1,301
1.084
Svstem Tvoe
CWS1
41
30
208
8
2
100
46
11
20
76
39
61
3
97
22
17
54
24
22
5
23
8
14
50
19
1
1
102
9
59
13
28
2
5
57
13
6
1,296
1.079
NTNCW
4
1
5
5
> 50,000
10
10
125
4
3
38
16
3
8
13
9
4
2
16
6
6
2
3
1
2
3
2
2
14
3
2
26
2
12
10
12
1
9
2
2
383
331
Svste
CWS1
10
10
124
4
3
38
16
3
8
13
9
4
2
16
6
6
2
1
2
26
2
12
10
12
1
9
9
2
382
330
n Tvoe
NCWS3
1
1
1
SYSTEMS
WITH
POP
DATA
54
152
6
973
3.627
60
1
13
853
1.165
127
1.002
1.307
415
525
13
210
998
139
1.563
84
206
565
298
214
201
1.551
617
10
8
2.655
335
306
124
430
3
133
978
139
145
22,205
20.780
SYSTEMS
WITH NO
POP
DATA4
694
540
2
10
2
1
349
2
14
1,614
1.254
TOTAL
PWSs
748
152
6
973
4.167
60
1
13
855
1.165
127
1.002
1.307
415
525
13
220
998
139
1.565
85
206
565
298
214
201
1.551
617
10
357
2.657
335
306
124
430
3
133
992
139
145
23,819
22.034
1. CWS= Community Water System
2. NTNCWS= Non-Transient Non-Community Water System
3. NCWS= Non-Community Water System-Transients
4. A total of 1,614 systems in the URCIS (Round 1) database do not contain population data and, therefore, the population size categories could not be determined for these systems.
15
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
III. SDWIS/FED (ROUND 2) DATA OVERVIEW
In this section of the report, the monitoring results for the UCM (1993) list of unregulated
contaminants, from Round 2 (approximately 1992-1997), are analyzed and reviewed. These Round 2
data (as discussed in Section I) were derived from the Safe Drinking Water Information System/Federal
Version (SDWIS/FED). Significant data review, formatting, and data quality checking and editing were
required of these Round 2 data to enable the evaluations and analyses conducted for this initial
contaminant occurrence assessment.
III.A. Description of Data
Data for this study were downloaded from EPA's SDWIS/FED database, and include information
on unregulated contaminants ("unregulated" contaminants are not formally regulated by EPA, but
monitoring of these contaminants is required, and therefore, many occurrence data are available). The
unregulated data include records from the second round of unregulated contaminant monitoring (referred
to as "Round 2") that were submitted directly into SDWIS/FED (see Section I.E. for more details).
The analyses in this section of the report are based on this SDWIS/FED (Round 2) data, which
were generated through monitoring conducted during the second round of required unregulated
contaminant monitoring initiated in 1993 (i.e., UCM [1993]). (Although second round monitoring was
formally initiated in 1993, SDWIS/FED (Round 2) data can include older data that are comparable to, but
predate, the formal second round monitoring.) The SDWIS/FED (Round 2) database includes
information on 48 contaminants, including: 1 IOC, 13 SOCs, 20 mandatory VOCs and 14 discretionary
VOCs. These data are from 35 States/primacy entities.
III.B. Data Management and Data Quality
The SDWIS/FED (Round 2) data from the 35 States/primacy entities contained a total of
4,350,874 (raw) records. An important and substantial component of this study consisted of the detailed
and extensive review of these data records for numerous data quality considerations including reporting
consistencies, uniform and valid coding, data completeness, correct and consistent use of analytical units,
and any inherent bias in the raw records. (The sources of bias are discussed later in this section.) To
ensure data quality for sound and dependable occurrence analysis, extensive data review, checking, and
editing were required. This data management and quality review process identified and addressed
problematic data or data that could not be uniquely categorized. The following are common types of data
problems that were addressed: records with invalid contaminant codes, systems with unknown source
water or system type codes, State records for specific contaminants that reported only detections, or entire
State records that appeared to have extremely and consistently low analytical results. These types of
records were either deleted (such as when water source or system type codes were invalid) or converted
(when a data units conversion appeared straightforward). For example, upon detailed review, the data
from five States -Kentucky, Michigan, North Carolina, Oregon and Washington- appeared to have been
recorded in incorrect units. In these cases, detailed double-checking with the analytical results for other
Round 2 States, with URCIS (Round 1) data, as well as with original State data sets (when available)
showed that the analytical results appeared to be incorrect (too low) by a constant factor of 1,000. The
data were (mistakenly) recorded in (ig/L in the database, but actually represented data in mg/L. These
data corrections were somewhat straightforward after identifying, reviewing, and cross-checking the
analytical results. Other specific data editing examples are listed below in Section III.C.
Another more general data management decision related to data from transient and "non-public"
water systems. Transient PWSs were not required by federal rule to monitor for most of the contaminants
of interest in this study. However, some States required monitoring, and some transient system
contaminant occurrence data is included in SDWIS/FED. By definition, the transient nature of these
PWSs confound the types of contaminant exposure assessments ultimately to be conducted for this study.
To avoid the problems associated with transient sources in exposure studies, systems with a system type
recorded as "NC" (non-community, meaning transient) were not included in the occurrence analyses. In
the raw Round 2 data, 24% of the total number of systems were listed as "NC", and were omitted from
the occurrence analyses. Also, 0.3% of the total number of systems were identified as "NP", or non-
16
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
public. Since this is not a valid system type code (and the exact definition of non-public could not be
determined), records designated as NP were also omitted from the analyses. Note that although the
systems identified as NC (transient) or NP (non-public) represented slightly more than 24% of the total
number of systems, these systems represent only 3.2% of the analytical sample results.
With these data quality improvements, the initial 4,350,874 analytical records from the 35
States/primacy entities for the 48 contaminants decreased to 4,211,446 analytical records for this Round 2
analysis (which includes the approximately 900,000 records with converted units).
III.C. SDWIS/FED (Round 2) Data Bias and Representativeness: Further Data Quality Review
and Editing
Subsequent to this initial editing and filtering of the data, a basic analysis of the 4.21 million
records was undertaken. Similar to the URCIS (Round 1) data, various descriptive statistics were
compiled by State to enable a further more detailed data review to assess data bias and representativeness.
Some State data, as described below, are seriously biased because they are so incomplete, and should only
be used with caution for any statistical summary of occurrence.
Table III.C. 1 summarizes some key results from this next stage of Round 2 data review. The
table summarizes the data availability and data quality for 57 primacy entities considered under SDWA
(the 50 States, 5 territories and the District of Columbia, and an aggregate entry for the Native American
tribes). Of the 57 primacy entities in SDWIS/FED (Round 2), 35 have reported Round 2 data and 22
have not. The table also provides an overview of data quality, and presents the list of 20 States (the States
identified with data sets of adequate quality and completeness) that comprise the 20-State cross-section
for Round 2 data.
Of the 35 States with Round 2 data, 15 States have incomplete data and/or data of inadequate
quality. For two States (Alabama and Mississippi), the percent of samples with detections (with
analytical results greater than the minimum reporting level; "Percent Sample Detections") ranged from
70-100%. These States are listed in Table III.C. 1 in the column labeled "Data sets with 100% Detects."
These States reported only (or mainly) analytical records for detections and, hence, their data sets are
highly biased (over-representing occurrence) and are therefore excluded from additional analysis. As can
be seen in the table, the percent samples with detections typically range from 1% to 8% for States with
approximately complete data reporting. An additional secondary check on these two States excluded
based on reporting only analytical detections is the measure of the number of samples per PWS. The
numbers of samples per PWS for Alabama (2 samples/PWS) and Mississippi (4 samples/PWS) are
significantly below the common range of 50 to 250 samples per PWS in most States. In addition to this
clear source of bias, we also reviewed the apparent completeness of the data related to the number of
PWSs represented.
The number of unique PWSs included in each State's data sets, and the number of samples per
PWS, are also included in Table III.C.I. These summary statistics provide a perspective on the relative
completeness of reporting. The number of PWSs included were compared to the total number of non-
purchased CWSs and NTNCWSs in the current State inventory, and to the number of non-purchased
CWSs and NTNCWSs serving more than 500 people (since not all small systems may have had to
conduct this monitoring). Most States approximated or exceeded 100% of one of these comparative
inventory numbers. The States listed in the "Too Few Systems" column have data reported from far
fewer systems than listed in the current State inventory. For example, New Jersey (17 PWSs) and
California (67 PWSs) have far too few systems with data in SDWIS/FED (Round 2) based on this
comparison. Therefore, to reduce potential analytical results bias, New Jersey, California, and seven
other States are excluded from the analyses since a significant portion of PWSs in these States do not
have contaminant occurrence data in SDWIS/FED (Round 2).
States with data quality problems are also indicated in Table III.C. 1. The data from Louisiana,
Pennsylvania, South Carolina, and Vermont were very problematic. For instance, 100% of the data
reported by Louisiana (for a very large number of systems and samples) were non-detections; there were
no positive analytical findings of contaminant occurrence in the 164,492 sample results reported. Data
17
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
from the other three States were very inconsistent (e.g., data for VOCs within a single State appeared to
be reported in mixed units). The level of detail and effort required to check and correct these types of
data problems with State data management staff (if possible at all) are beyond the resources and schedule
of this study. The data from these four States were excluded from the analysis.
The last column in Table III.C.I, "Residual of Usable States," lists States with data records that
are reasonably balanced and perhaps complete for the systems that did report. These 20 Round 2 primacy
entities with adequate and unbiased data were further considered for occurrence analyses.
Table III.C.l. Summary of Data Quantity and Quality in SDWIS/FED (Round 2) for the States, Tribes
and Territories.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
State/ Tribes/
Territories
Alabama
Alaska
American Samoa
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
Florida
Georgia
Guam
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Marianna Islands
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
Total
Unique
PWSs
314
625
123
577
67
833
87
-
-
-
120
-
445
1,394
745
-
1,015
506
3,209
1,581
1,155
1,434
-
849
17
755
2,263
296
2,259
888
1,168
Percent
Sample
Detections
94.08%
3.10%
2.75%
7.29%
6.75%
3.72%
4.53%
2.26%
7.50%
0.00%
0.89%
0.62%
3.12%
7.26%
1.66%
71.27%
6.08%
5.45%
2 32%
0.75%
2.05%
7.73%
3.45%
3.99%
1.66%
Samples
per PWS
0
194
55
118
44
143
921
58
125
118
163
140
125
97
198
4
109
23
28
277
55
59
291
180
75
No Data in
Database
American Samoa
Delaware
Florida
Georgia
Guam
Hawaii
Idaho
Illinois
Iowa
Kansas
Marianna Islands
Montana
Nebraska
Nevada
New York
Data sets
with 100%
Detects
Alabama
Mississippi
Significantly
Too Few
Systems
Arizona
California
Connecticut
Indiana
New Jersey
Data Quality
Problems
Louisiana
States Usable
for Cross-
Section
Alaska
Arkansas
Colorado
Kentucky
Maine
Maryland
Massachusetts
Michigan
Minnesota
Missouri
New Hampshire
New Mexico
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
18
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
State/ Tribes/
Territories
Pennsylvania
Puerto Rico
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Tribes
Utah
Vermont
Virgin Islands
Virginia
Washington
Washington, D.C.
West Virginia
Wisconsin
Wyoming
TOTAL
Total
Unique
PWSs
1,424
117
1,047
27
78
4,863
26
-
636
-
2,680
-
225
-
33,848
Percent
Sample
Detections
10.32%
0.30%
0.33%
2.34%
9.31%
1.23%
1 22%
2.65%
2.23%
1.41%
2.95%
Samples
per PWS
16
136
147
40
147
124
57
74
123
51
124
No Data in
Database
Puerto Rico
Utah
Virgin Islands
Virginia
Washington, D.C.
West Virginia
Wyoming
22
Data sets
with 100%
Detects
2
Significantly
Too Few
Systems
South Dakota
Tennessee
Tribes
Wisconsin
9
Data Quality
Problems
Pennsylvania
South Carolina
Vermont
4
States Usable
for Cross-
Section
Rhode Island
Texas
Washington
20
The next level of data evaluation assessed the analytical results for each State in even more detail.
For example, the minimum, median, 99th percentile, and maximum analytical values were determined for
every contaminant in each State. With this more in-depth level of analysis, some additional data quality
problems were identified within the data sets of the 20 Round 2 cross-section States. Most of these
problems were determined to be specific to certain contaminants (or contaminant groups). With
additional data editing efforts, these problems have either been resolved or the problematic portion of data
omitted from further analysis.
The Arkansas data problem is limited to the VOCs. There were 73 very similar, low VOC
detections at 73 different PWSs (one VOC detection at each of 73 PWSs). The resulting calculated
percent of systems and percent of samples with analytical detections for these 73 VOCs was nearly
identical. Also, the percent of detections in Arkansas for these VOCs was considerably higher (up to 100
times higher) than that of any other State. Through several communications with the data management
staff in Arkansas, it was determined that these records were actually semi-quantitative analytical results at
levels below the method reporting level and had been mistakenly recorded as analytical detections (rather
than non-detections). To correct this mistake, the Arkansas VOC records with a reported concentration of
less than 0.5 (ig/L (the EPA VOC detection limit) were changed to non-detects, correcting the
problematic analytical results.
Massachusetts SOC data were also problematic. Massachusetts reported Round 2 sample results
for SOCs from only 56 PWSs, while reporting VOC results from over 400 PWSs. Massachusetts SOC
data also contained an atypically high percentage of systems with analytical detections when compared to
all other States. Through communications with Massachusetts data management staff, it was learned that
the State's SOC data, as well as the SDWIS/FED (Round 2) Massachusetts SOC data, were incomplete.
For instance, the SDWIS/FED (Round 2) data for Massachusetts indicates 18% systems with reported
detections of aldrin. The average percent of systems with aldrin detections for all other States was 0.2%.
In contrast, Massachusetts data characteristics and quantities for lOCs and VOCs were reasonable and
comparable with other States' results. Therefore, Massachusetts was included in the group of 20
SDWIS/FED (Round 2) cross-section States with usable data for lOCs and VOCs, though its SOC data
were omitted from occurrence analyses and summaries.
Other types of data problems were present in Pennsylvania. After an initial data review, the raw
Pennsylvania records indicated nearly a dozen analytical results with extremely high concentrations of
19
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
metribuzin. In fact, the raw data indicated that Pennsylvania was the only State with any analytical
results exceeding the health reference level (HRL) for metribuzin. Pennsylvania State data management
staff were contacted, and after their review of the data records, it was determined that all the very high
metribuzin concentrations that were reported were incorrect (likely with incorrect units) and these records
were deleted. (Pennsylvania State data were still not used in the cross-section analyses because there
appear to be significantly too few samples per system as well as an unusually high percentage of systems
with detections, indicating that many systems without analytical detections did not report results.)
The detailed data review also indicated that New Hampshire data contained only detections for
the 14 discretionary VOCs and these records were from no more than four PWSs. New Hampshire IOC
and SOC data quality and completeness appeared reasonable. Therefore, the State was retained in the
group of 20 cross-section States, but its data for the 14 discretionary VOCs were omitted from the
occurrence analyses and summaries. As summarized in Section V.B.2, SDWIS/FED (Round 2) data are
aggregated for a representative cross-section of 20 States, which is used as the basis for most of the
analyses in this report.
III.D. Data Characteristics Overview
A descriptive overview of the Round 2 data is presented in a series of tables to provide additional
insight and perspective on the results. Table III.D. 1 shows data elements included in SDWIS/FED for the
Round 2 UCM (1993) list contaminants, and Tables III.D.2 to III.D.7 characterize the data as based on
number of records, number of systems, source water type, system type, records by year and month, and
system size (population-served). As noted, after the initial data management and editing, 4.21 million
records were available for analysis from over 33,000 PWSs in the 35 States/entities. The 20 SDWIS/FED
(Round 2) State cross-section totals 3.69 million records from slightly more than 27,000 PWSs. The
Round 2 cross-section States, therefore, contain nearly 88% of all Round 2 State contaminant occurrence
data in SDWIS/FED (Round 2).
Table III.D.l. Data Elements Included in SDWIS/FED (Round 2) for UCM (1993) List Contaminants
Data Element
PWS Identification Number
Source Identification Number
Source Water Type
Ground water
Surface water
Chemical Abstract Services (CAS) Number
Contaminant Name
Contaminant Group
IOC
SOC
voc
Sample Date
Analysis Result
Detection Identifier
0
1
Community Type
Description
Nine digit identification number unique to each public water system
Three-digit code to identify the source
Ground water or purchased ground water
Surface water, purchased surface water, ground water under the direct influence of surface
water or purchased ground water under the direct influence of surface water
Unique numeric designation used to identify specific chemical compounds
Commonly used contaminant name
Inorganic Chemicals
Synthetic Organic Chemicals
Volatile Organic Chemicals
Date sample was collected (years 1992 through 1997)
Concentration of the sample (measured in micrograms/liter)
Code to determine if analysis result is greater than or less than the Minimum Reporting
Result is less than the Minimum Reporting Level
Result is greater than the Minimum Reporting Level
20
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Data Element
CWS
NCWS
NTNCWS
Population Served
Description
Community Water System
Non-Community (Transient) Water System
Non- Transient Non-Community Water System
Population served by the public water system
Table III.D.2 shows the number and percent of sample records and systems according to source
water type: approximately 89% of the systems in the 20-State cross-section are classified as ground water
and 11% as using surface water. These source water percentages are essentially the same for the entire
data set for all 35 States/entities. These SDWIS/FED (Round 2) data contained systems using "ground
water under the direct influence of surface water" (GUDI) as a source definition. The classification used
follows the regulatory guidelines: if a system uses any surface water (such as a GUDI), it is classified as
a surface water system.
Table III.D.2. SDWIS/FED (Round 2) Data - Number of Records and Systems by Source Water Type
SOURCE TYPE
Total - Ground Water
Total - Surface Water
Total
20 States - Ground Water
20 States - Surface Water
20 States - Total
RECORDS
NUMBER
3,479,102
732,344
4,211,446
3,085,266
609,619
3,694,885
PERCENT
82.6%
17.4%
100.0%
83.5%
16.5%
100.0%
SYSTEMS
NUMBER
30,085
3,763
33,848
24,199
2,909
27,108
PERCENT
88.9%
11.1%
100.0%
89.3%
10.7%
100.0%
Table III.D.3 shows the number and percent of records and systems by system type.
Approximately seventy percent of systems in the 20-State cross-section were coded as a "CWS"
(Community Water System) and 30% were coded as "NTNC" (Non-Transient Non-Community Water
System). The CWS percent was slightly higher for the entire 35 States/entities data set, and the percent
for NTNC correspondingly lower. As discussed earlier in Section III.B., systems coded as "NC" (Non-
Community Water System) were excluded from these analyses.
21
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table III.D.3. SDWIS/FED (Round 2) Data- Number of Records and Systems by System Type
SYSTEM TYPE
cws1
NTNCWS2
Total
20 States - CWS1
20 States - NTNCWS2
20 States - Total
RECORDS
NUMBER
3,255,222
956,224
4,211,446
2,808,341
886,544
3,694,885
PERCENT
77.3%
22.7%
100.0%
76.0%
24.0%
100.0%
SYSTEMS
NUMBER
24,357
9,491
33,848
19,055
8,053
27,108
PERCENT
72.0%
28.0%
100.0%
70.3%
29.7%
100.0%
1. CWS = Community Water System
2. NTNCWS = Non-Transient Non-Community Water System
Tables III.D.4 and III.D.5 show the distribution of data by years and by month (based on actual
sample collection or analysis date). The upper half of each table is for the entire 35 States/entities data set
while the lower half is for the 20-State cross-section data. Table III.D.4 indicates the amount of data
annually collected during the 1992-1997 compliance cycle, with a peak of data collection in 1995. And
in Table III.D.5, a fairly uniform distribution of occurrence data by month is shown, suggesting that there
should be no inherent seasonal bias in the data.
Table III.D.4. SDWIS/FED (Round 2) Data- Number of Records by Year and Source Water Type
YEAR
Total -1992
Total -1993
Total -1994
Total -1995
Total -1996
Total -1997
Total
20 States- 1992
20 States- 1993
20 States- 1994
20 States- 1995
20 States- 1996
20 States- 1997
20 States - Total
# SURFACE
WATER
RECORDS
39,487
130,993
130,127
144,006
157,152
130,579
732,344
33,187
115,859
105,673
112,144
136,182
106,574
609,619
# GROUND
WATER
RECORDS
243,426
622,010
586,066
816,442
647,717
563,441
3,479,102
187,558
592,555
504,410
711,443
589,788
499,512
3,085,266
TOTAL # OF
RECORDS
282,913
753,003
716,193
960,448
804,869
694,020
4,211,446
220,745
708,414
610,083
823,587
725,970
606,086
3,694,885
% OF TOTAL
RECORDS
6.7%
17.9%
17.0%
22.8%
19.1%
16.5%
100.0%
6.0%
19.2%
16.5%
22.3%
19.6%
16.4%
100.0%
22
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table III.D.5. SDWIS/FED (Round 2) Data- Number of Records by Month and Source Water Type
MONTH
Total - January
Total - February
Total - March
Total - April
Total - May
Total - June
Total - July
Total - August
Total - September
Total - October
Total - November
Total - December
Total
20 States - January
20 States - February
20 States - March
20 States - April
20 States - May
20 States - June
20 States - July
20 States - August
20 States - September
20 States - October
20 States - November
20 States - December
20 States - Total
# SURFACE
WATER
RECORDS
49,458
60,065
75,004
51,874
58,348
66,500
55,382
65,326
75,206
55,215
55,251
64,715
732,344
40,939
49,405
65,525
41,692
44,374
55,612
44,174
52,087
65,814
46,113
46,492
57,392
609,619
# GROUND
WATER
RECORDS
254,507
248,888
343,572
284,793
275,219
316,326
296,042
302,726
328,634
289,789
241,581
297,025
3,479,102
221,420
211,499
305,597
257,085
245,051
285,159
262,611
266,475
293,692
254,688
213,295
268,694
3,085,266
TOTAL # OF
RECORDS
303,965
308,953
418,576
336,667
333,567
382,826
351,424
368,052
403,840
345,004
296,832
361,740
4,211,446
262,359
260,904
371,122
298,777
289,425
340,771
306,785
318,562
359,506
300,801
259,787
326,086
3,694,885
% OF TOTAL
RECORDS
7.2%
7.3%
9.9%
8.0%
7.9%
9.1%
8.3%
8.7%
9.6%
8.2%
7.0%
8.6%
100.0%
7.1%
7.1%
10.0%
8.1%
7.8%
9.2%
8.3%
8.6%
9.7%
8.1%
7.0%
8.8%
100.0%
Table III.D.6 summarizes the number of systems and population served for each State by
population-served size categories and Table III.D.7 provides a more detailed, population and system-type
stratification of the number of PWSs by State. Population-served information is available for essentially
all systems. Eight systems are listed as having a population-served equal to "0", but these constitute only
about 0.02% of the total systems represented (and have insignificant affect on aggregate analyses).
The analytical findings of the occurrence data for the 6 CCL contaminants (aldrin, dieldrin,
hexachlorobutadiene, metribuzin, naphthalene, and sulfate) from the 20 SDWIS/FED (Round 2) cross-
section States are developed and summarized in Section VI of this report.
23
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table III.D.6. Total Number of Public Water Systems by State and Population Size Category Contained in the SDWIS/FED (Round 2) Database
State
Alaska
Alabama
Arkansas
Arizona
California
Colorado
Connecticut
Indiana
Kentucky
Louisiana
Massachusetts
Maryland
Maine
Michigan
Minnesota
Missouri
Mississippi
North Carolina
North Dakota
New Hampshire
New Jersey
New Mexico
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Tribes
Texas
Vermont
Washington
Wisconsin
TOTAL
20 States
<500
Systems
516
232
245
102
5
600
4
77
304
944
280
780
714
10,098
1,144
959
399
1,747
190
726
13
575
1,882
529
941
649
99
805
13
10
9
3,904
514
2,694
82
32,785
28.927
3op. Served
82,449
13,520
49,621
13,779
1,252
87,645
702
12,026
36,175
132,904
36,200
116,705
79,877
368,683
143,991
145,609
87,494
254,268
30,785
85,760
1,530
88,107
236,040
84,271
128,271
117,468
11,267
93,828
1,585
2,102
2,680
455,733
73,516
269,080
14,931
3,359,854
2.790.537
501-3,300
Systems
88
128
230
33
7
179
34
22
110
425
88
210
118
659
361
377
639
384
90
101
4
135
543
300
180
541
13
183
9
27
13
1,458
94
410
122
8,315
6.034
3op. Served
89,197
199,444
325,237
38,611
14,288
243,936
56,708
29,566
181,895
642,165
114,886
237,585
150,203
611,150
469,447
510,668
870,441
477,007
123,068
111,804
6,700
164,972
648,312
425,444
264,102
726,644
16,051
250,076
14,042
45,058
23,663
2,043,889
122,789
493,377
159,230
10,901,655
7 702 230
3,301-10,000
Systems
16
80
72
7
11
34
18
18
75
132
67
31
19
90
61
95
112
94
7
15
0
25
127
67
34
140
6
53
5
23
5
404
23
89
16
2,071
1.428
'op. Served
99,948
452,530
413,469
47,595
65,908
207,337
124,968
100,284
444,806
745,184
435,505
167,560
105,646
477,254
342,925
541,291
586,717
537,119
42,024
87,062
0
154,164
795,018
391,360
205,788
828,059
28,418
322,170
24,504
131,093
29,563
2,191,545
130,636
502,421
86,342
11,846,213
8.170.660
10,001-50,000
Systems
5
45
24
7
20
33
79
9
55
49
92
21
12
50
56
34
38
76
8
11
1
17
111
33
36
98
9
40
1
15
0
165
7
80
19
1,299
928
3op. Served
93,565
946,697
395,956
151,900
586,871
664,762
601,981
210,465
1,126,179
908,659
2,252,879
480,423
226,155
1,026,615
1,174,498
653,463
814,699
1,551,578
208,201
212,831
20,000
386,299
2,310,695
722,050
741,645
2,184,747
269,020
891,882
17,592
279,173
0
3,428,011
133,820
1,839,251
371,826
27,884,388
19.764.076
>50,000
Systems
1
6
6
3
25
13
9
-)
5
15
16
7
1
16
12
7
1
17
1
-)
0
3
28
8
6
29
3
8
0
3
0
44
1
14
8
320
210
3op. Served
114,909
1,314,000
500,810
656,523
3,801,723
2,373,200
1,548,582
170,318
1,278,206
2,233,197
2,990,361
4,019,601
113,560
2,194,717
1,532,855
972,276
205,895
2,281,321
74,111
208,000
0
572,900
5,233,485
1,460,880
949,930
5,932,445
435,551
1,074,883
0
335,205
0
10,054,831
56,000
1,983,113
1,209,416
57,882,804
39.344.617
TOTAL
WITH POP
DATA
626
491
577
152
68
859
87
128
549
1,565
543
1,049
864
10,913
1,634
1,472
1,189
2,318
296
855
18
755
2,691
937
1,197
1,457
130
1,089
28
78
27
5,975
639
3,287
247
44,790
37.527
SYSTEMS
WITH NO
POP DATA1
1
-)
1
1
5
10
9
TOTAL
Systems
626
491
578
152
68
859
87
128
549
1,565
543
1,051
864
10,913
1,634
1,472
1,189
2,318
296
855
18
756
2,691
937
1,197
1,457
130
1,089
29
78
27
5,980
639
3,287
247
44,800
37.536
Pop. Served
480,068
2,926,191
1,685,093
908,408
4,470,042
3,576,880
2,332,941
522,659
3,067,261
4,662,109
5,829,831
5,021,874
675,441
4,678,419
3,663,716
2,823,307
2,565,246
5,101,293
478,189
705,457
28,230
1,366,442
9,223,550
3,084,005
2,289,736
9,789,363
760,307
2,632,839
57,723
792,631
55,906
18,174,009
516,761
5,087,242
1,841,745
111,874,914
77.772.120
24
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table III.D.7. Number of Public Water Systems by State, System Type and Population Size Category Contained in the SDWIS/FED (Round 2)
Database
State
Alaska
Alabama
Arkansas
Arizona
California
Colorado
Connecticut
Indiana
Kentucky
Louisiana
Massachusetts
Maryland
Maine
Michigan
Minnesota
Missouri
Mississippi
North Carolina
North Dakota
New Hampshire
New Jersey
New Mexico
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Tribes
Texas
Vermont
Washington
Wisconsin
TOTAL
20 States
Population Size Category (Population Served by System)
<500
TOTAL
515
59
244
76
4
580
4
69
203
781
247
745
599
2,551
1,093
923
367
1,693
190
720
12
574
1,487
480
912
619
86
764
11
10
8
2,843
512
2,130
62
22,173
18,815
System Type
CWS1
515
23
172
56
4
465
4
21
95
627
132
340
271
845
452
726
306
1,245
147
436
443
597
334
596
388
39
467
11
10
8
2,138
313
1,849
51
14,126
11,837
NTNCWS2
36
72
20
115
48
108
154
115
405
328
1,706
641
197
61
448
43
284
12
131
890
146
316
231
47
297
705
199
281
11
8,047
6,978
501 - 3,300
TOTAL
88
124
230
30
7
173
34
79
107
419
84
209
114
515
359
375
638
383
90
101
4
135
506
300
180
539
13
182
9
27
13
1,407
93
371
120
8,001
5,740
System Type
CWS1
88
107
221
25
7
159
34
17
89
372
48
106
87
335
307
332
589
269
89
57
109
358
294
153
372
6
131
9
27
13
1,265
80
320
120
6,595
4,692
NTNCWS2
17
9
5
14
5
18
47
36
103
27
180
52
43
49
114
1
44
4
26
148
6
27
167
7
51
142
13
51
1,406
1,048
3,301 - 10,000
TOTAL
16
80
72
7
11
34
18
18
75
130
67
31
19
82
61
95
111
94
7
15
0
25
127
67
34
139
6
53
5
23
5
401
23
86
16
2,053
1,414
System Type
CWS1
16
80
70
6
11
32
18
18
75
130
67
30
19
79
60
94
109
93
7
15
25
125
66
34
136
5
51
5
23
5
395
23
85
16
2,023
1,392
NTNCWS2
2
1
2
1
3
1
1
-)
1
2
1
3
1
9
6
1
30
22
10,001 - 50,000
TOTAL
5
45
24
7
20
33
22
9
55
49
92
21
12
49
56
34
38
76
8
11
1
17
111
33
36
98
9
40
1
15
0
165
7
79
19
1,297
926
System Type
CWS1
5
45
24
7
19
32
22
9
55
49
92
21
12
48
56
34
37
76
8
11
1
17
111
33
36
98
9
39
1
15
164
7
79
19
1,291
923
NTNCWS2
1
1
1
1
1
1
6
3
> 50,000
TOTAL
1
6
6
3
25
13
9
2
5
15
16
7
1
12
12
7
1
17
1
2
0
3
28
8
6
29
3
8
0
3
0
44
1
14
8
316
206
System Type
CWS1
1
6
6
3
25
13
9
9
5
15
16
7
1
11
12
7
1
17
1
9
3
28
8
6
29
3
8
3
44
1
14
8
315
205
NTNCWS2
1
1
1
SYSTEMS
WITH
POP
DATA3
625
314
576
123
67
833
87
120
445
1,394
506
1,013
745
3,209
1,581
1,434
1,155
2,263
296
849
17
754
2,259
888
1,168
1,424
117
1,047
26
78
26
4,860
636
2,680
225
33,840
27,101
SYSTEMS
WITH
NO POP
DATA4
1
-)
1
1
3
8
7
TOTAL
SYSTEMS
625
314
577
123
67
833
87
120
445
1,394
506
1,015
745
3,209
1,581
1,434
1,155
2,263
296
849
17
755
2,259
888
1,168
1,424
117
1,047
27
78
26
4,863
636
2,680
225
33,848
27,108
1. CWS= Community Water System
2. NTNCWS= Non-Transient Non-Community Water System
3. The values in this column indicate the number of PWSs that have population-served information. Although some PWS records contained no population served information, the missing population-
served values were acquired from the more complete population records of the 1999 Needs Survey.
4. This column indicates the number of PWSs for which no population-served information is contained in SDWIS/FED or the 1999 Needs Survey, and therefore population size categories for these
systems could not be determined.
25
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
IV NATIONAL INORGANICS AND RADIONUCLIDES SURVEY (NIRS) DATA
In this section of the report, the EPA's National Inorganics and Radionuclides Survey (NIRS)
data are described and reviewed. NIRS occurrence data are assessed for the two CCL inorganic
chemicals (lOCs) of interest, manganese and sodium, and are applicable for PWSs served by ground
water.
IVA. Description of Data
The NIRS survey was conducted by EPA specifically to provide data on the occurrence of a
select set of radionuclides and inorganic chemicals (lOCs) being considered for National Primary
Drinking Water Regulations (NPDWRs). The NIRS provides contaminant occurrence data from 989
community water systems served by ground water sources. Each of these randomly (statistically) selected
public water systems was sampled a single time between 1984 and 1986. The selection of this group of
PWSs was designed so that the contaminant occurrence results from these PWSs are representative of
national occurrence of contaminants in ground water systems.
The NIRS sample design included random selection of a number of systems from each size
category in proportion to the number of PWSs in those size categories nationally. The resulting sample
number of systems represented approximately 2% of the nation's community ground water supply in each
system size category. Therefore, since there are many more small than large PWSs in the US, most of the
NIRS data are from smaller systems. In aggregate, approximately 95% of the analytical sample results in
the entire NIRS database indicate no detections of the contaminants sampled and analyzed. The NIRS
database includes information on 42 contaminants, including: 36 lOCs (including 10 regulated lOCs), 2
regulated radionuclides, and 4 unregulated radionuclides. The data are from 49 States (there are no data
from Hawaii), as well as Puerto Rico. Two contaminants from the NIRS are used here for CCL analyses:
manganese and sodium.
IVB. Representativeness
By design, the data collected and contained in the NIRS database are nationally representative for
ground water systems, and furthermore, can be divided into strata based on system size for additional
statistical resolution. Especially when compared to the URCIS and SDWIS/FED databases, there are few
contaminant occurrence data quality or completeness issues with the NIRS data set. For example, some
States have no data in URCIS or SDWIS/FED and many State records in URCIS or SDWIS/FED reflect
incomplete data (e.g., records of only analytical detections, or records from only a small percentage of
PWSs within a State); therefore, these databases must be extensively reviewed and modified to provide
data that is reflective of national occurrence of contaminants. In contrast, the NIRS contains analytical
results that were specifically collected to establish a nationally representative sample, so the sample is
"complete and adequate" simply by correct implementation of the sample selection design. Also, there
are often computational (statistical) problems resulting from multiple laboratory analytical detection
limits that must be addressed in the analysis of occurrence data. In the case of NIRS (for the two lOCs
being evaluated ) analytical methods with uniform detection limits were employed. Therefore, the
extensive concerns and problems with data quality, completeness, and representativeness encountered in
the use of URCIS and SDWIS/FED data are not issues when considering the use of the NIRS data.
NIRS was structured as a stratified, random sampling of the nation's community ground water
supplies as they existed in the mid-1980s. The stratification for sample selection was based on system
size. However, the sampling frame used in NIRS was not specifically designed to be representative of
ground water supplies on a State-by-State, regional, or other geographic basis.
IVC. Data Characteristics Overview
A descriptive overview of the data is presented in a series of tables to provide additional insight
and perspective on the results (remembering that the NIRS sampling was designed to be a randomly
selected, nationally representative survey for ground water systems). The NIRS database included data
26
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
from 989 PWSs from 49 States and Puerto Rico. Summary results for all States are included in the
following results tables.
Table IV.C. 1 shows data elements included in NIRS. Note that a special data element was
developed in NIRS to distinguish between a detection and a result below the minimum reporting level.
When a value was flagged as a "non-detection", the detection limit, or MRL, was recorded in the
analytical result field.
Table IV.C.l. Data Elements Included in NIRS Database
Data Element
Sample Number
City
State
Zip
Contaminant
Sample Date
Analysis Result
Detection Identifier
N
D
POP 1QUART
POP 2QUART
POP 3QUART
POP 4QUART
AVG POP
Description
NIRS Sample Number (unique four digit identification number)
City served by the public water system
State served by the public water system
Zip code served by public water system
Identified by Molecular Formula
Date sample was collected (years 1984 through 1986)
Concentration of the sample (measured in milligrams/liter)
Code to determine if analysis result is greater than or less than the Minimum Reporting Level
Result is less than the minimum detection limit
Result is greater than the minimum detection limit
Population served by public water system during 1 * quarter of calender year
Population served by public water system during 2nd quarter of calender year
Population served by public water system during 3rd quarter of calender year
Population served by public water system during 4th quarter of calender year
Average Population served by the public water system during year
Tables IV.C.2 and IV.C.3 show the distribution of data by years and by month across all years.
The data were collected between 1984 and 1986, with a peak of data collection in 1985. Somewhat more
samples were collected in 1985, and a somewhat larger proportion of samples was collected in the fall
months of September, October, and November (though seasonal effects for the occurrence of lOCs in
groundwater is likely not high). Table IV.C.4 summarizes the number of systems by population-served
size categories. The analytical findings of the occurrence data for the two CCL contaminants from the
NIRS data are developed and summarized in Section VI. C of this report.
Table IV.C.2. NIRS Data- Number of Records by Year
YEAR
1984
1985
1986
TOTAL
NUMBER OF
RECORDS
268
466
255
989
PERCENT OF
TOTAL RECORDS
27.1%
47.1%
25.8%
100.0%
27
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table IV.C.3. NIRS Data- Number of Records by Month
MONTH
Total - January
Total - February
Total - March
Total - April
Total - May
Total - June
Total - July
Total - August
Total - September
Total - October
Total - November
Total - December
Total
NUMBER OF
RECORDS
19
29
63
92
70
68
92
94
118
153
132
59
989
PERCENT OF TOTAL
RECORDS
1.9%
2.9%
6.4%
9.3%
7.1%
6.9%
9.3%
9.5%
11.9%
15.5%
13.3%
6.0%
100.0%
Table IV.C.4. Total Number of Public Water Systems by State and Population Size Category Contained
in the NIRS Database
State
Alaska
Alabama
Arkansas
Arizona
California
Colorado
Connecticut
Delaware
Florida
Georgia
Iowa
Idaho
Illinois
Indiana
Kansas
Kentucky
Louisiana
Massachusetts
Maryland
Maine
Michigan
Minnesota
Missouri
Mississippi
Montana
North Carolina
<500
Systems
8
1
0
9
45
7
22
4
37
17
14
8
24
8
2
6
14
2
5
6
13
13
12
13
8
36
Pop.
Served
957
40
0
1,475
4,502
955
3,547
451
6,314
2,578
2,988
719
5,438
1,438
262
882
1,798
500
755
779
2,168
3,166
2,388
3,565
853
4,942
501-3,300
Systems
0
6
7
5
7
3
0
5
11
3
11
1
15
9
3
2
10
3
0
1
9
4
6
9
3
8
Pop.
Served
0
7,786
9,563
4,690
12,041
2,800
0
7,536
17,196
3,539
16,031
580
15,339
11,833
2,804
3,460
14,790
4,900
0
828
10,926
5,340
7,634
11,595
4,092
7,003
3,301 - 10,000
Systems
0
1
1
0
6
0
0
1
4
-)
2
0
4
1
1
0
2
9
1
0
3
1
3
0
0
0
Pop.
Served
0
7,000
7,800
0
36,630
0
0
4,500
23,630
7,820
12,278
14,800
20,348
4,870
7,272
0
13,967
14,383
9,357
0
20,270
4,506
13,804
13,527
0
0
10,001 - 50,000
Systems
0
0
1
2
0
0
1
0
1
1
1
1
2
1
0
0
0
0
0
0
0
1
0
2
0
0
Pop.
Served
0
0
12,500
34,500
0
0
13,400
0
35,000
13,000
15,528
10,500
29,904
12,000
0
0
0
0
0
0
0
13,750
0
25,453
0
0
> 50,000
Systems
0
0
0
0
0
3
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Pop.
Served
0
0
0
0
0
261,661
0
0
0
70,000
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
TOTAL
Systems
8
8
9
16
58
13
23
10
53
24
28
12
45
19
6
8
26
7
6
7
25
19
21
26
11
44
Pop.
Served
957
14,826
29,863
40,665
53,173
265,416
16,947
12,487
82,140
96,937
46,825
26,599
71,029
30,141
10,338
4,342
30,555
19,783
10,112
1,607
33,364
26,762
23,826
54,140
4,945
11,945
28
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
State
North Dakota
Nebraska
New Hampshire
New Jersey
New Mexico
Nevada
New York
Ohio
Oklahoma
Oregon
Pennsylvania
Puerto Rico
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Virginia
Vermont
Washington
Wisconsin
West Virginia
Wyoming
TOTAL
<500
Systems
13
16
10
4
5
0
45
15
8
5
30
0
1
15
3
4
52
7
25
10
46
19
5
3
675
Pop.
Served
2,415
3,392
1,018
320
928
0
6,979
1,869
1,184
1,455
3,594
0
30
1,657
216
811
7,859
1,581
2,585
1,363
4,730
3,239
581
310
101,576
501-3,300
Systems
5
3
0
1
2
2
10
9
1
2
5
0
0
3
4
4
17
2
4
2
5
8
2
0
232
Pop.
Served
4,769
2,621
0
2,000
3,250
1,350
14,390
16,194
1,500
1,350
6,286
0
0
5,693
5,062
7,683
24,019
4,425
4,226
2,425
3,990
8,715
1,110
0
303,364
3,301 - 10,000
Systems
0
0
0
1
0
0
0
0
3
1
1
1
0
0
1
0
1
1
1
0
0
3
0
0
53
Pop.
Served
0
0
0
9,000
0
0
0
0
16,880
5,000
5,100
5,764
0
0
4,060
0
3,400
5,500
8,370
0
0
14,700
0
0
314,536
10,001 - 50,000
Systems
1
0
0
0
0
0
2
1
0
0
0
0
0
0
0
1
4
0
0
0
1
0
1
0
25
Pop.
Served
10,099
0
0
0
0
0
62,953
15,320
0
0
0
0
0
0
0
10,784
88,100
0
0
0
14,205
0
14,000
0
430,996
> 50,000
Systems
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
Pop.
Served
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
331,661
TOTAL
Systems
19
19
10
6
7
2
57
25
12
8
36
0
1
18
8
9
74
10
30
12
52
30
8
3
989
Pop.
Served
17,283
6,013
1,018
11,320
4,178
1,350
84,322
33,383
19,564
7,805
14,980
5,764
30
7,350
9,338
19,278
123,378
11,506
15,181
3,788
22,925
26,654
15,691
310
1,482,133
IV.D. Supplemental IOC Data
Efforts were made to identify data sources from surface water systems to supplement the NIRS
data since they derive only from ground water systems. There were no data for manganese or sodium in
either the URCIS or SDWIS/FED databases. Sulfate data were available in both URCIS and
SDWIS/FED, for both surface and ground water systems, and were analyzed for this report (with findings
presented in Section VI).
Additional State data sets, obtained directly from the States, were also reviewed for supplemental
IOC data. Detailed data review has shown that these State data sets contain more analytical records than
do the State data sets downloaded from SDWIS/FED covering the same monitoring periods. Nonetheless,
there are still a very limited number of analytical records for occurrence of the two CCL priority lOCs in
these eight State data sets (see Table IV.D.l).
29
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table IV.D.l. Number of Analyses and Public Water Systems in the 8 Cross-Section State Data Sets for
Manganese and Sodium by Source Water Type
State
Alabama
California
Illinois
Michigan
Montana
New Jersey
New Mexico
Oregon
Manganese
Number of Samples
GW
934
29,923
275
N/A
N/A
2,795
N/A
409
SW
409
2,075
69
N/A
N/A
401
N/A
365
Number of PWSs
GW
365
3,176
160
N/A
N/A
1,147
N/A
69
SW
69
342
67
N/A
N/A
32
N/A
30
Sodium
Number of Samples
GW
917
25,111
313
N/A
N/A
3,941
N/A
1,506
SW
410
2,383
70
N/A
N/A
476
N/A
813
Number of PWSs
GW
366
3,043
160
N/A
N/A
1,411
N/A
863
SW
69
336
67
N/A
N/A
33
N/A
169
N/A = No data available for contaminant
For the analyses conducted in the CMR Report (USEPA, 1999), a "national cross-section" was
constructed using the data obtained directly from these specific eight States. In aggregate, these eight
States provide contaminant occurrence data that are indicative or representative of national occurrence.
Though some of the States in Table IV.D.l have a large amount of IOC data, the obviously incomplete
data record for the aggregation of the eight States prohibits the use of these data as the basis of any
national occurrence analyses.
V.
DEVELOPING A NATIONALLY REPRESENTATIVE PERSPECTIVE
As discussed in Sections I and II, the URCIS database contains contaminant occurrence data from
a total of 40 States, and territories (38 States plus Washington, D.C. and Virgin Islands). However, data
from many States are incomplete and biased. Our evaluation suggested that data from 25 States (plus
D.C. and the Virgin Islands, totaling 27 primacy entities) were most complete and might be used to
generate national summary statistics on occurrence of the contaminants in URCIS. Data from 25 of the
50 States is indeed a substantial sample. The data from all of these States could simply be aggregated to
compute a composite, national occurrence value for a contaminant. However, even a 50% sample does
not guarantee that the sample is representative because the data were not collected in a systematic or
random statistical framework. The 50% sample could be heavily skewed to low-occurrence or high-
occurrence settings. Hence, the State data were evaluated to assess how representative they were across
the range, from high to low, of likely contaminant occurrence and across the spatial/hydrologic diversity
of the nation. Based on these assessments, the construction of a cross-section of States from the available
State data sets would provide a reasonable representation of national occurrence.
There are many sophisticated statistical methods that can be applied to analyze limited (and
biased) data. However, this first stage of evaluating the URCIS (Round 1) occurrence data was to
establish a representative cross-section of data for first-stage analyses. This representative cross-section
would also be the basis for subsequent analyses as deemed necessary and appropriate by the findings. For
this initial analysis, we used the approach that was developed for the CMR Report (USEPA, 1999) to
establish a national cross-section from State SDWA contaminant databases. This approach was supported
by peer reviewers and by stakeholders as providing a clear, repeatable, and understandable approach. It
30
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
cannot provide a "statistically representative" sample, because the data were not selected in an appropriate
fashion. The resultant data should, however, provide a clear indication of the central tendency of the
national data.
V.A. Methods
For the CMR Report (USEPA, 1999), a protocol was developed for determining a representative
cross-section of States for occurrence analysis. In the CMR analysis, contaminant data were available
from 14 States. The State data were evaluated for completeness and quality, similar to the analysis in this
report. The balance of the States were evaluated to establish a national cross-section. In the CMR
process, eight States were selected for use in a national analysis as providing the best data quality and
completeness, and for providing a balanced national cross-section of occurrence data. The CMR process
was based on evaluating the States' pollution potential and geographic coverage in relation to all States.
The URCIS (Round 1) and SDWIS/FED (Round 2) States were evaluated using the same selection
process.
Two broad factors were considered in the assessment of a representative cross-section: pollution
potential and geographic or spatial diversity. Pollution potential is considered to ensure that the selection
of cross-section States represents the range of likely high, medium, and low contaminant occurrence.
Geographic consideration is included so that the wide range of climatic and hydrogeologic conditions
across the United States are represented, again balancing the varied conditions that affect transport and
fate of contaminants. Many past EPA studies have shown that some simple measures, such as population
(or population density) are valid indicators of pollution, because it is human activity and its related land
use that is the source of most pollutants, particularly the organic chemicals. Various demographic and
other factors were evaluated as independent measures or indicators of pollution potential. (Over 30
factors were evaluated in the CMR report; only the final approach is described here.)
For this analysis, two primary pollution potential indicators were used to evaluate the
representativeness of the States. The first factor indicates the pollution potential from manufacturing and
the second factor refers to pollution potential from agriculture in each State. (Manufacturing and
population density typically are related to the occurrence of VOCs, many of which are industrial
chemicals, for example. Most of the SOCs of concern are pesticides, and the greatest use of most of these
is in agriculture.) States were ranked from 1 to 50 for each factor and divided into quartiles based on the
ranking. The rankings were reviewed to assess if States could be selected in approximate balance from
each quartile. In addition, some secondary pollution potential indicators were also considered to further
ensure that the data were representative.
V.A.1. Manufacturing Indicators
Numerous factors were considered as potential indicators of manufacturing-related pollution,
including EPA's Toxics Release Inventory (TRI) (including total releases, releases per square mile, and
releases excluding air releases), the number of manufacturing establishments, the number of
manufacturing establishments per square mile, the number of manufacturing employees, the value added
by manufacturers, and the value added per capita. This information was taken directly from the 7995
Annual Survey of Manufactures (USDOC, 1997), the 7992 Census of Manufactures (USDOC, 1996), and
the 7995 Toxics Release Inventory (USEPA, 2001). All factors were each considered in terms of their
inherent value as pollution potential indicators, their range and variance (in providing a relative ranking
of the States), and their inter-relationships.
The total TRI releases per square mile, number of manufacturing establishments per square mile,
and value added per capita were considered the three most useful indicators. The TRI was considered
useful because it is a measure of how many pounds of toxic chemicals are released within the State.
While there are problems with the TRI (e.g., some inconsistent release estimation techniques; omission of
many small establishments, or those with releases below specified thresholds), it is valid to use as a direct
indicator of potential pollutants released. The number of manufacturing establishments takes into account
how many factories are actually engaged in manufacturing and thus how many establishments potentially
contribute to pollution. By breaking down the number of manufacturing establishments per square mile,
31
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
the size of the State is also taken into account. The final factor that was considered to be viable was the
value added by manufacturers per capita. Initially this seemed to be a well-suited measure because of the
presumed correlation between value added and the level of production (and by-product pollution) within
the State. The problem with this measure (and also with the measure of number of manufacturing
establishments per square mile), is that it does not take into account the variation in pollution released by
different industries. For example, an industry that adds a lot of value to a product may cause little
pollution while another industry that does not add much value may contribute more pollution.
The data clearly showed a close correlation between the number of manufacturing establishments
per square mile and the population density in each State, as well as a clear linear association with the total
TRI pounds released/square mile, number of manufacturing employees, and total value added. Hence, the
number of manufacturing establishments per square mile was used as the primary indicator because it is a
simple measure of how many establishments are actually engaged in manufacturing and thus are
potentially polluting sources of drinking water. The TRI total pounds released per square mile was used
as a secondary factor in determining representativeness. Squillace et al. (1999) found a significant
correlation between VOC occurrence in ambient ground water and population density in a USGS national
NAWQA study. As noted, population density and manufacturing density are highly correlated.
Manufacturing density and TRI data were used in this ranking because they were considered more direct
measures of pollution potential for this study.
V.A.2. Agricultural Indicators
There is no complete measure of pesticide usage by States that is readily available. Thus, a
variety of factors were considered to assess potential organic chemical pollution from agriculture in each
State. These included the percent of the State's population that is classified as rural, the percent of land in
the State that is crop land, the percent of land that is grassland pasture and rangeland (a possible inverse
indicator), and total farm agricultural chemical expenses. Like the manufacturing factors, these
agricultural variables were considered in terms of their value in indicating potential sources of pollution
and were plotted against one another to determine how closely they are correlated.
Of these factors, total farm agricultural chemical expenses was considered to be the best indicator
of potential pollution. The percent of the State's population that lives in rural areas does not necessarily
relate to agricultural chemical use or crop land. There is, of course, a correlation between crop land and
agricultural chemical use. However, there are notable exceptions such as Florida and California which
use a large amount of agricultural chemicals despite having more limited crop land area. While there are
some incomplete surveys of pesticide use, the 7992 Census of Agriculture (USDOC, 1994) measure of
dollars spent on agricultural chemicals was a more consistent and complete measure.
V.B. Representative Cross-Section of States
Table V.B.I summarizes the pollution potential rankings for the 50 States, highlighting those
included in URCIS (Round 1). Although a total of 38 State data sets, as well as data for Washington B.C.
and Virgin Islands, are included in URCIS (Round 1) data, not all States were usable in constructing a
"representative" cross-section, as discussed in Section II. Thirteen States contained only detections or too
few analytical records, or records from too few PWSs and were eliminated from consideration because of
their inherent bias. The data from Washington, B.C. and Virgin Islands were excluded from this State-
level analysis because it was difficult to evaluate them in relation to complete State data, for the current
purposes. (The number of data from these entities is few and they can easily be added in for later review.)
The data quality screening left 25 States eligible for the national cross-section. As noted in Section II,
New York was also excluded because of inherent data quality problems, leaving 24 States.
32
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table V.B.I. Ranking of States based on Number of Manufacturing Establishments per Square Mile.
URCIS (Round 1) 24-State Cross-Section in Bold.
State
Rhode Island
tfew Jejtpey
Connecticut
M»jp.33
|4
IS
Jp&
If
I§
.,49
,39 /
m
,32
^1
34
35
3«
37
.3-8
39
,40
,41
A2 -'
43
,44
x4f
,,4«
47
,4§
,-49
,10
1= highest
Ranking of the Total Farm Ag.
Chemical Expenses
49
m
45
f3
28
,'11
35
29
M
2
,,'1
4
If
,«
7
^7 .••
20
24
,'19
30
32
as
4.7
,-'14
2fi
12
,,'2f
,5
13
6
8
10
44
22
38
3
33
31
16
15
42
?
23
40
2-1
46
15
34
41
,50
1= highest
All 50 States are ranked based on the number of manufacturing establishments per square mile. Each State's rank in total farm agricultural
chemical expenses is also indicated. The 38 States in highlighted rows are the States with data in the URCIS (Round 1) database. The 24 States
in bold are the selected URCIS (Round 1) cross-section States. Ranking quartiles are indicated by bold lines.
33
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
This group of 24 States (the States with the best data quality) were evaluated for their pollution
potential rankings and geographic coverage. Figure V.B.I summarizes the representativeness of the
pollution potential distribution of the 24 cross-section States. As illustrated, the 24 States are well
distributed based on pollution potential indicators, with a uniform distribution from high to low potential
for both key pollution indicators. Figure V.B.2 shows the geographic distribution of these 24 cross-
section States as well as the distribution of the States not in the cross section. Spatially the 24 States
cover a substantial portion of the country. While coverage is lacking from the south-central U.S. and
New England, these States provide broad coverage from around the country, from the major climatic
regions. The 24 States include about 49% of the PWSs nationally and about 56% of population served by
PWSs.
Figure V.B.I. Distribution of State Rankings for Manufacturing Establishments / Sq. Mile vs. FarmAg.
Chemical Expenses. Highlighting URCIS (Round 1) 24 Cross-Section States
g of fee No. of Manufacturing Eslabfisliraraits/ Scf. Mile
TO
o
o c
o
*
*
» * .
o
*
0«
o
o
o c
o
*
o
o
o
*
*
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*
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o
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O >•> Stutci V 11 ml Ri ISiK«tind l-i H«.-.-S,MJ<'I
34
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure V.B.2. 24 URCIS (Round 1) Representative Cross-Section States and States Not Included in the
Cross-Section
URCIS (Round 1)
URCIS (Round 1) States
I I States not in Cross-Section (no data)
I I States with biased data
24 Cross-Section States
(data used in report)
In sum, the group of 24 cross-section States in URCIS (Round 1), should provide a balanced
representation, based on relative rankings for pollution potential (i.e., potential for contaminant
occurrence), geographic coverage, and data quality and completeness. The 24 cross-section State
distribution across pollution potential quartiles suggests that they should provide a valid indication of the
potential range and occurrence of contamination in PWSs nationally. The data from the 24-State cross-
section is used to compute aggregate contaminant occurrence measures as an approximation of a national
cross-section. While the data from these cross-section States cannot be Stated to be "statistically
representative," their distribution should provide a clear indication of national central tendency of
occurrence.
In addition, the URCIS (Round 1) data, with 24 States in its cross-section, represent a relatively
large collection of State data for a cross-section. As noted, the CMR analysis developed a cross-section
of eight States. (The Round 2 unregulated data cross-section, discussed later in this section, has 20 States
used for analyses.) The data from the URCIS 24 States can also be used to evaluate and illustrate this
approach to constructing a national cross section by evaluating the data in aggregate steps, using
increments of the 24 States. This is described below.
V.B.I. Incremental National Cross-Sections
The data from the 24 URCIS cross-section States were used to build "incremental" national cross-
sections, by aggregating subsets of the 24 States using the same, described selection protocol for
evaluating representativeness. Each aggregation (e.g., 4 States, 8 States, etc.) provides some
representation from all quartiles of pollution potential indicators, a geographic balance, and, hence,
hopefully, a balance in potential occurrence. The data from the States in each aggregation were used to
compute group contaminant occurrence measures as an approximation of a national cross-section.
The CMR analysis suggested that a minimum of 6-7 States were needed to provide balance based
on both geography and pollution potential. The CMR report used eight States out of the available data.
35
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
(Unfortunately, the same eight States could not be used in this analysis because data were not available
for all of them. The eight State cross-section here in the incremental build-up, though, is a close
approximation to the eight States used in the CMR.) For this comparison, the first cross-section is
composed of four States, and additional States are added to this in increments. Hence, the first group of
four States (NJ, GA, IA, and MT) is composed of one State from each quartile, with the States covering a
broad geographic range. Additional States were added, maintaining the distribution of pollution potential
and spatial diversity, to develop composite 8- and 13-State cross-sections. The statistical data from these
aggregations can be compared with the results from the 24 States, the 16 States/territories with the biased
data, and the results of all 40 States/territories, to evaluate and illustrate the differences.
The States included in each cross-section or group are:
4 States: NJ, GA, IA, MT
8 States: NJ, GA, IA, MT, CA, NC, KY, NM
13 States: NJ, GA, IA, MT, CA, NC, KY, NM, OH, TN, AL, SD, AZ
24 States: NJ, GA, IA, MT, CA, NC, KY, NM, OH, TN, AL, SD, AZ, AK, FL, HI, IL, IN,
MD, MN, UT,WA,WV,WY
16 (biased) States: AR, CO, DC, DE, LA, MA, MI, MO, MS, NE, NH, NV,
NY, TX, VI, VT
All (40) States: NJ, GA, IA, MT, CA, NC, KY, NM, OH, TN, AL, SD, AZ, AK, FL, HI,
IL, IN, MD, MN, UT, WA, WV, WY, AR, CO, DC, DE, LA, MA, MI,
MO, MS, NE, NH, NV, NY, TX, VI, VT
Figure V.B. 1 .a shows the pollution potential ranking distribution of the first eight States and the
last 16 States used in the 24-State cross-section, for comparison. Table V.B. 1 .a, summarizes occurrence
results from the various State groups for five of the URCIS (Round 1) contaminants: a relatively high-
occurrence VOC, trichloroethylene (TCE); a very high occurrence VOC that occurs from pollutant
sources and as a THM-chlorination by-product, chloroform; and three more typical, low occurrence
VOCs, bromobenzene, hexachlorobutadiene, and 1,3-dichloropropene.
36
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure V.B.I.a. Distribution of State Rankings for Manufacturing Establishments / Sq. Mile
vs. Farm Ag. Chemical Expenses. URCIS (Round 1) 24-State Representative Cross-Section Build-up
€Mo. of Md Ut.KH
1
O
n
*
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O
O
*
O
O
O
«
O
J
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Table V.B.I.a. Summary and Comparison of Occurrence Results for Incremental National
Cross-Sections in URCIS (Round 1).
States
TOTAL #
SAMPLES
TOTAL
UNIQUE PWS
% SAMPLES
>MRL
% PWS
>MRL
%
POPULATION
>MRL
% PWS
> HRL/MCL*
MEDIAN
DETECTS
Olg/L)
BROMOBENZENE
4 States
8 States
13 States
24 States
14 States/ Biased1
All (40) States
8,443
14,059
34,597
56,174
3,457
59,631
4,038
5,599
9,630
16,450
488
16,938
0.02%
0.06%
0.05%
0.07%
0.23%
0.08%
0.02%
0.13%
0.15%
0.19%
1.64%
0.24%
0.03%
2.21%
2.69%
3.17%
0.84%
3.07%
N/A
N/A
N/A
N/A
N/A
N/A
1.85
3.65
1.48
1.00
1.00
1.00
37
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
States
TOTAL #
SAMPLES
TOTAL
UNIQUE PWS
% SAMPLES
>MRL
% PWS
>MRL
%
POPULATION
>MRL
% PWS
> HRL/MCL*
MEDIAN
DETECTS
Olg/L)
CHLOROFORM
4 States
8 States
13 States
24 States
14 States/ Biased1
All (40) States
9,538
28,757
40,392
63,826
4,919
68,745
4,245
9,303
12,717
20,184
1,038
21,222
31.10%
27.17%
25.74%
28.38%
66.62%
31.11%
30.67%
23.59%
24.74%
28.63%
77.75%
31.03%
82.81%
76.36%
77.24%
79.17%
95.09%
81.04%
0.05%
0.03%
0.02%
0.02%
0.00%
0.02%
5.40
3.00
4.00
4.80
6.40
5.00
1,3-DICHLOROPROPENE
4 States
8 States
13 States
24 States
14 States/ Biased1
All (40) States
4,157
8,390
24,733
31,104
869
31,973
2,220
3,366
6,667
9,164
143
9,307
0.07%
0.04%
0.02%
0.06%
1.04%
0.09%
0.14%
0.09%
0.09%
0.16%
2.80%
0.20%
3.65%
1.26%
0.73%
0.91%
3.28%
0.95%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
1.30
1.30
1.15
1.00
2.00
1.00
HEXACHLOROBUTADIENE
4 States
8 States
13 States
24 States
14 States/ Biased1
All (40) States
1,630
7,950
27,020
42,839
2,710
45,549
801
2,797
6,669
12,284
484
12,768
0.37%
0.08%
0.08%
0.13%
0.11%
0.13%
0.75%
0.21%
0.28%
0.35%
0.62%
0.36%
0.56%
0.06%
0.67%
0.86%
0.06%
0.82%
0.25%
0.07%
0.12%
0.11%
0.62%
0.13%
0.12
0.12
0.83
0.25
6.00
0.30
TRICHLOROETHYLENE*
4 States
8 States
13 States
24 States
14 States/ Biased1
All (40) States
4,235
28,464
38,274
53,674
4,713
58,387
2,402
7,346
10,135
15,290
628
15,918
4.53%
22.83%
17.82%
13.80%
28.37%
14.97%
3.04%
4.61%
3.93%
3.54%
24.84%
4.38%
0.43%
63.49%
59.39%
55.49%
34.73%
55.00%
0.87%
1.51%
1.30%
0.99%
9.08%
1.31%
1.85
3.10
3.10
3.00
3.00
3.00
14 States plus DC, VI
The comparative results illustrate several points. The representative cross-section results for the
percentage of systems (or percentage of samples, or population served by systems) with detections are
quite stable and consistent for the 8-, 13- and 24-State cross-sections. The 4-State data are generally more
variable, and more obviously different from the larger cross-sections. Sometimes the four State values are
greater, sometimes smaller than the 8-, 13-, and 24-State values. For the 8-, 13-, and 24-State data, the
values for the percent samples and the percent population vary more than the percent systems, as would
be expected.
The values for the percent samples or systems with detections are always greater for the 16 biased
States, typically much greater than the cross-section States, i.e., 25% of PWS with detections of TCE
compared to 4% for the national cross-section. (The one exception is for the percent of
38
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
hexachlorobutadiene samples with detections.) The percent population using drinking water with
detections is not always greater for the 16 biased States, but this is in part because the population data are
so incomplete for these States. Because the 16 biased States have such a strong bias of increased
occurrence, occurrence results using all 40 States are typically greater than the national cross-section, as
well.
The 8-State through the 24-State cross-sections provide comparable results. The results are
consistent and all look usable to provide a national cross-section that can provide an estimate of
contaminant occurrence. Obviously, having data from more States is desirable, as long as they are
balanced related to pollution potential and spatial coverage. Table V.B. l.b shows the results for TCE
with three other comparisons. Results from five high-occurrence States (i.e., all in the top quartile for
manufacturing density), five low-occurrence (all lowest quartile) and a regionally-biased sample (4
Midwestern States) are shown for comparison. These comparative data further support the selection
approach and illustrate the value of establishing the national cross-section. While more data is desirable,
it is evident that having an appropriately selected 8-State sample is more representative than the wrong 16
States. The validity and value of the national cross-section sample could be further tested if necessary.
Table V.B.l.b. Trichloroethylene Occurrence for the URCIS (Round 1) Cross-Section States and
Comparative Biased Groups of States
States
TOTAL #
SAMPLES
TOTAL
UNIQUE
PWS
% SAMPLES
>MRL
% PWS
>MRL
% POPULATION
>MRL
% PWS
>MCL
MEDIAN
DETECTS
Olg/L)
TRICHLOROETHYLENE
4 States
8 States
13 States
24 States
14 States / Biased1
All (40) States
High Occ.2
Low Occ.3
Regional Occ.4
4,235
28,464
38,274
53,674
4,713
58,387
28,227
5,952
9,107
2,402
7,346
10,135
15,290
628
15,918
7,304
1,974
2,085
4.53%
22.83%
17.82%
13.80%
28.37%
14.97%
23.25%
0.66%
6.25%
3.04%
4.61%
3.93%
3.54%
24.84%
4.38%
4.12%
0.96%
2.69%
0.43%
63.49%
59.39%
55.49%
34.73%
55.00%
63.84%
1.00%
24.14%
0.87%
1.51%
1.30%
0.99%
9.08%
1.31%
1.45%
0.30%
1.06%
1.85
3.10
3.10
3.00
3.00
3.00
3.10
1.90
1.40
1. 14 States plus DC, VI
2. High Occurrence States: CA, IL, MD, NJ, OH
3. Low Occurrence States: AZ, MT, NM, SD, UT
4. Regional Occurrence States: IA, IL, IN, OH
This consistency of analytical results among the different national cross-section groups supports
the validity of the criteria used to construct the State aggregations. Again, while the data from these
cross-section States cannot be Stated to be "statistically representative," their distribution should provide
a clear indication of national central tendency of occurrence. The results using the 24-State cross-section
will be further described in the following section of this report.
V.B.2. SDWIS/FED (Round 2) 20-State Cross-Section
After the checking and editing processes of the SDWIS/FED (Round 2) data, a group of 20 States
-with the exceptions noted in Section III.C.- remained for which the data were relatively unbiased,
complete, and of good quality. These 20 SDWIS/FED (Round 2) cross-section States were then
evaluated for their pollution potential rankings and geographic coverage. The pollution potential ranking
of all States (with these 20 cross-section States identified in bold) are presented in Table V.B.2.a. In
Figure V.B.2.a, the distribution of the pollution potential rankings of the 20 cross-section States illustrates
how representative the cross-section States are as based on these characteristics.
39
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table V.B.2.a. Ranking of States based on Number of Manufacturing Establishments per Square Mile.
SDWIS/FED (Round 2) 20 Cross-Section States in Bold.
State
Rhode Isl:l nd
Ness- Jersey
Ponneetieut
Mas»a,e|jUjsetts
New York
OMo
Marytaml
Pennsylyartla
Delaware
Illinois
California
Fl ori da
Michigan
New Hampshire
Indiana
'Ptoiftli,
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure V.B.2.a. Distribution of State Rankings for Manufacturing Establishments / Sq. Mile vs. Farm
Ag. Chemical Expenses. Highlighting SDWIS/FED (Round 2) 20 Cross-Section States
of lite No. of Manufacturing Establishments/ Sq, Mile
0
• c
o
o
ft
o
° o
o
*
o
0
m
o •
•
.
o
o
=„••
o
o
o
o
0 •
°0
3
*
0 °
o
o
*
I
&
* SDWIS/FED (Round 2) 20-Stais Cross-Section
O 30 States NOT ill SDWIS/FED (Round 1) Cross-Section
41
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
The geographic distribution of the 20 SDWIS/FED (Round 2) cross-section States is shown in
Figure V.B.2.b, with some of the characteristics of the remaining 30 (non-cross-section) States also
identified. Even with some cluster of States in the central portion of the quartiles, these 20 cross-section
States appear relatively well distributed based on pollution potential indicators, with a fairly uniform
distribution, from high to low potential, for both key pollution indicators (see Figure V.B.2.a). This broad
distribution appears relatively comparable to that of the 24 URCIS (Round 1) cross-section States.
Geographically, the 20 Round 2 cross-section States cover a substantial portion of the country. These
States are also distributed across the country. Although coverage is perhaps sparse in the south-east and
along the western slope of the Rocky Mountains, every major geographic region has some State
representation.
Figure V.B.2.b. 20 SDWIS/FED (Round 2) Cross-Section States and States Not Included in the Cross-
Section
SDWIS/FED (Round 2)
SDWIS/FED (Round 2) States
I I States not in Cross-Section (no data)
I I States with biased data
IgjSI 20 Cross-Section States
(data used in report)
VI. ANALYSIS OF NATIONAL OCCURRENCE
This section of the report contains detailed occurrence assessments of the eight CCL priority
contaminants. As described in Section I of this report, the occurrence data for the UCM (1987)
contaminants are from the URCIS database, and are referred to as the "URCIS (Round 1) data." The
occurrence data for UCM (1993) contaminants are from the SDWIS/FED database, and are referred as the
"SDWIS/FED (Round 2) data." The NIRS data are used to assess occurrence of two lOCs on the CCL
priority list. In the following section (Section VII), a series of graphs and maps are presented as a
complimentary graphical evaluation of the occurrence of the CCL priority contaminants.
The summary data developed for the occurrence assessments are presented in detail in
Appendices A through E. Appendix A contains summary tables for the two URCIS (Round 1)
contaminant data. Appendix B contains summary tables for the six SDWIS/FED (Round 2) contaminant
data. Summary tables for the two NIRS contaminant data are presented in Appendix C. In Appendix D,
data coverage comparisons between URCIS (Round 1) and SDWIS/FED (Round 2) data are presented for
select States and contaminants. Data summaries of select contaminants by system type and population-
served for both URCIS (Round 1) and SDWIS/FED (Round 2) data are presented in Appendix E. At the
42
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
beginning of the Appendices section, a complete List of Appendix Tables identifies all tables included in
the five appendices. Also included are "Notes to Accompany Unregulated Contaminant Occurrence Data
Tables" which presents definitions of terms and phrases commonly used in the many tables, graphs, and
maps included in this report and its appendices.
VI.A. URCIS (Round 1) Contaminant Occurrence
The development of URCIS (Round 1) 24-State cross-section is described in detail in Section V
of this report, and these 24 cross-section States are included in Figure V.B.2. Table VI.A.l summarizes
the occurrence data of the URCIS (Round 1) 24-State cross-section for two CCL priority contaminants.
The table presents the total number of unique public water systems, the percent of public water systems
with at least one analytical result greater than the Minimum Reporting Level (MRL), the percent of public
water systems with at least one analytical result greater than the estimated Health Reference Level (HRL)
and, finally, the 99th percentile value in micrograms per liter (|ig/L). More detailed assessment of
occurrence findings will be presented later in this section, but some general observations are made here
based on the findings presented in Table VI.A.l.
The 24 States used in the URCIS (Round 1) cross-section reflect a significant national coverage:
these States contain approximately 44% of public water systems nationally and 51% of the population
served by public water systems. Analytical detections of the CCL contaminants in public water systems
are relatively similar in ground water and surface water systems. The percent of systems with at least a
single sample analytical result greater than the HRL is less than 0.11% for both of these VOCs.
Table VI.A.l. URCIS (Round 1) Data - 24-State Cross-Section Summary of Occurrence for CCL
Contaminants
CHEMICAL NAME
(HRL in p,g/L)
Total #
PWS
#GW
PWS
#sw
PWS
% PWS
>MRL
%GW
PWS
>MRL
%SW
PWS
>MRL
% PWS
>HRL
%GW
PWS
>HRL
%
sw
PWS
>
99%
Value
(Hg/L)
VOCs
Hexachlorobutadiene
(HRL=0.9)
Naphthalene
(HRL=140)
12,284
13,452
10,980
12,034
1,385
1,502
0.35%
1.18%
0.30%
1.08%
0.72%
1.93%
0.11%
0.01%
0.06%
0.02%
0.51%
0.00%
<5.0
<5.0
PWS = Public Water Systems; GW = Ground Water (PWS Source Water Type); SW = Surface Water (PWS Source Water Type); MRL =
Minimum Reporting Limit (for laboratory analyses); HRL = Health Reference Level (concentration values used only as reference levels for
analyses in this report.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
A complete presentation of the occurrence data for the two CCL contaminants in URCIS (Round
1) is provided in Appendix A. There is a set of three tables of occurrence data for each of the
contaminants. The first table of each set (Tables A.I.a, A.2.a) contain the system-level data summarized
in Table VI. A. 1 (above), but present the data for all individual States (rather than just the aggregate data
from the 24 States in the cross-section). Tables A. l.b and A.2.b provide sample-level data and additional
descriptive statistics, including the total number of analyses and the percent of samples with at least one
result greater than the MRL. These tables also include the minimum concentration value, 99th percentile
value, maximum concentration value, minimum concentration value of analytical detections and median
value of analytical detections. Tables A. l.c and A.2.c provide similar detailed analytical measures, but
provide system-level statistics (as compared to the sample-level statistics in Tables A.l.b and A.2.b).
VLB. SDWIS/FED (Round 2) Contaminant Occurrence
The SDWIS/FED (Round 2) 20 cross-section States are discussed in Section V of this report, and
are identified in Figure VB.2.b. Table VI.B.I summarizes the occurrence data of the SDWIS/FED
(Round 2) 20 cross-section States for six CCL priority contaminants. This table presents the total number
of unique public water systems, the percent of public water systems with at least one result greater than
the Minimum Reporting Level (MRL), the percent of public water systems with at least one result greater
43
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
than the Health Reference Level (HRL) and, finally, the 99th percentile value in micrograms per liter
(|ig/L). Some general observations based on Table VLB. 1 are made here, with additional assessments of
occurrence findings presented later in this section.
The 20 States used in the SDWIS/FED (Round 2) cross-section reflect a significant national
coverage: these States contain approximately 41% of public water systems nationally and 34% of the
population served by public water systems. For the contaminants evaluated here, with the exception of
sulfate, less than 1% of public water systems in the cross-section States have analytical detections.
Analytical detections of three contaminants (aldrin, dieldrin, and metribuzin) are found in less than 0.1%
of PWSs, suggesting very low levels of national occurrence. The two VOCs, hexachlorobutadiene and
naphthalene, occur in 0.18% and 0.75% of PWSs, respectively, also exhibiting low national occurrence as
based on the SDWIS/FED (Round 2) data. Sulfate has a considerably higher percent of systems with one
or more sample analytical results greater than the MRL (approximately 88%). The percent of systems
with at least one sample analytical result greater than the sulfate HRL of 500,000 (ig/L is 0.79% and for
the sulfate HRL of 1,000,000 (ig/L is 0.39%. The percent of systems with at least one sample analytical
result greater than the HRL for all other contaminants is less than 0.09%.
Table VI.B.l. SDWIS/FED (Round 2) Data - 20-State Cross-Section Summary of Occurrence for CCL
Contaminants
CHEMICAL NAME
(HRL in (ig/L)
Total
PWS
#GW
PWS
#sw
PWS
%
PWS
>MRL
%GW
PWS
>MRL
%SW
PWS
>MRL
%
PWS
>HRL
%GW
PWS
>HRL
%SW
PWS
>HRL
99%
Value
ftig/L)
IOCS
Sulfate1
(HRL=500,000)
Sulfate1
(HRL=1,00,000)
16,495
16,495
15,009
15,009
1,486
1,486
88.11%
88.11%
87.76%
87.76%
91.66%
91.66%
1.79%
0.39%
1.83%
0.38%
1.41%
0.54%
560,000
560,000
SOCs
Aldrin2
(HRL=0.002)
Dieldrin2
(HRL=0.002)
Metribuzin2
(HRL=91)
11,745
11,788
13,512
10,420
10,329
11,833
1,325
1,459
1,679
0.01%
0.09%
0.01%
0.01%
0.09%
0.01%
0.00%
0.14%
0.00%
0.01%
0.09%
0.00%
0.01%
0.09%
0.00%
0.00%
0.14%
0.00%
<2.0
< 1.0
<2.0
VOCs
Hexachlorobutadiene3
(HRL=0.9)
Naphthalene3
(HRL=140)
22,736
22,923
20,380
20,524
2,356
2,399
0.18%
0.75%
0.13%
0.62%
0.59%
1.92%
0.02%
0.00%
0.00%
0.00%
0.13%
0.00%
< 1.0
<2.0
1. Sulfate data were analyzed using two different HRLs and are, therefore, listed twice.
2. Massachusetts data not included in summary statistics for this contaminant.
3. New Hampshire data not included in summary statistics for this contaminant.
PWS = Public Water Systems; GW = Ground Water (PWS Source Water Type); SW = Surface Water (PWS Source Water Type);
MRL = Minimum Reporting Limit (for laboratory analyses); HRL = Health Reference Level (concentration values used only as reference levels
for analyses in this report.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
Appendix B contains complete occurrence summaries for the CCL contaminants contained in
SDWIS/FED (Round 2) data. There is a set of three tables of occurrence data for each of the six
contaminants (similar in construction to the table sets in Appendix A). The first table of each set (Tables
B.I.a, B.2.a, etc., through B.6.a) contain the system-level summary data presented in Table VI.B.l
(above), but present the data for all individual States. Tables B. 1 .b through B.6.b provide sample-level
data and additional descriptive statistics, including the total number of analyses and the percent of
samples with at least one result greater than the MRL. These tables also include the minimum
concentration value, 99th percentile value, maximum concentration value, minimum concentration value
of analytical detections and median value of analytical detections. Tables B.l.c through B.7.c provide
similar detailed analytical measures, but provide system-level statistics.
44
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
VI.C. NIRS Contaminant Occurrence
The NIRS data are discussed in Section IV of this report. Table VI.C.I summarizes the
occurrence data of the NIRS (for ground water systems only) for two CCL priority contaminants. This
table presents the total number of unique public ground water systems represented in the survey, the
percent of surveyed public water systems with at least one result greater than the MRL, the percent of
surveyed public water systems with at least one result greater than the HRL (or benchmark) and, finally,
the 99 percentile value in micrograms per liter (|ig/L). Some general observations based on Table
VI.C.I are made here, with additional assessments of occurrence findings presented later in this section.
For the contaminants evaluated here, a large portion of surveyed public water systems have analytical
detections, ranging from 67.95% of PWSs with detections of manganese to 100% of the surveyed PWSs
with detections of sodium. (Note that sodium in various forms can be used in water treatment.) The
percent of systems with at least one sample analytical result greater than the HRL (or benchmark) is
relatively high for both of these lOCs. (Note that these results are for ground water systems only, and that
the NIRS survey was designed to provide statistically valid results for ground water systems nationally.)
Table VI.C.l. NIRS Data - Summary of Occurrence for Priority Contaminants
CHEMICAL NAME
(HRL in mg/L)
Total
PWS
% PWS
>MRL
% PWS
> H HRL '
% PWS
>HRL'
99% Value
(mg/L)
lOCs
Manganese
(HRL=0.30)
Manganese
(HRL=0.05)
Sodium
(Benchmark=30)
Sodium
(Benchmark=120)
989
989
989
989
67.95%
67.95%
100.00%
100.00%
6.07%
23.66%
52.48%
22.65%
3.24%
15.98%
36.91%
13.25%
0.63
0.63
516.83
516.83
1. In the case of sodium, a benchmark, rather than an HRL, was chosen based on taste thresholds and effects, which occur at lower
concentrations than health effects.
PWS = Public Water Systems; MRL = Minimum Reporting Limit (for laboratory analyses); HRL = Health Reference Level (concentration values
used only as reference levels for analyses in this report.
Note: Manganese data were analyzed using two different HRLs and sodium data were analyzed using two different benchmarks. Therefore,
both manganese and sodium are listed twice.
In Appendix C, Table C.I through Table C.2 summarize the NIRS data coverage for the two
inorganic contaminants. Each table illustrates the total number of samples, the number and percent of
samples with at least one result greater than the MRL, the number and percent of samples with at least
one result greater than !/> the estimated HRL (or benchmark), and the number and percent of samples with
at least one result greater than the estimated HRL (or benchmark). These tables also include descriptive
statistics, such as the minimum concentration value, 99th percentile value, maximum concentration value,
minimum concentration value of analytical detections and median value of analytical detections in
milligrams per liter (mg/L). Since the NIRS data contain one sample per public water system, the number
and percent of samples calculated to be greater than the MRL ("> MRL"), greater than half the HRL (or
benchmark) ("> 0.5 HRL") or greater than the HRL (or benchmark) ("> HRL") are identical to the
number and percent of systems that are greater than the MRL, 0.5 HRL (or benchmark) or HRL (or
benchmark), respectively, for each contaminant. Therefore, the data require presentation only once, based
on the number of samples. (Note: Manganese and sodium data were analyzed using two different HRLs
(or benchmarks). Therefore, summary data for these contaminants are presented separately for each HRL
(or benchmark).)
Since the NIRS data were taken from a select group of nationally representative public water
systems (served by ground water), the percentage of samples (or systems) exceeding various thresholds
listed here are also estimates of national occurrence. For example, since 3.24% of NIRS systems sampled
for manganese have detections greater than the HRL (HRL = 0.30 mg/L), it can be concluded that
45
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
approximately 3.24% of systems sampled nationally for manganese will have detections greater than the
specified HRL.
VI.D. Comparing Data Coverage of URCIS (Round 1) and SDWIS/FED (Round 2)
The URCIS (Round 1) and SDWIS/FED (Round 2) data were evaluated to determine if
comparable States, public water systems, and contaminants are contained in both databases. As
previously noted, URCIS (Round 1) contained data from 40 States/territories and SDWIS/FED (Round 2)
contained data from 35 States/territories.
Table VI.D.l lists the States in URCIS (Round 1) and SDWIS/FED (Round 2), highlighting the
States common to both. Although 25 States are common to both Rounds 1 and 2, most of these States
could not be considered for this analysis because of data quality issues (see Table II.C. 1 and Table
III.C.I). Many States reported analytical results from a very low proportion of systems, reported results
in mixed units, and/or reported only analytical detections (highly censored reporting) in Round 1 and/or
Round 2.
Of the 25 States in both URCIS (Round 1) and SDWIS/FED (Round 2) (highlighted in Table
VI.D.l), only eight were determined to be sufficiently complete for use in this comparison analysis.
Alaska, Kentucky, Maryland, Minnesota, North Carolina, New Mexico, Ohio, and Washington (in bold in
Table VI.D. 1) were contained in both databases and have data of adequate quality for analyses and
comparisons.
Table VI.D.l. States Common to both URCIS (Round 1) and SDWIS/FED (Round 2)
States/ Tribes/
Territories
Alaska
Alabama
Arkansas .'
American Samoa
Arizona
California
Colorado
Connecticut
Washington, D.C.
Delaware
Florida
Georgia
Guam
Hawaii
Iowa
Idaho
Illinois
Indiana
Kansas
Kentucky
Louisiana
Massachusetts
Maryland
Maine
Michigan
Minnesota
Misseuri •.
Marianna Islands
Mississioci
URCIS (Round 1)
24 Cross-Section
States (used in
comparison)
/
/
/
/
/
/
/
/
/
/
/
^
-.-•../ • •
' '
16 Other States
(not used in
comparison)
X
X
X
X
X
X
X
-..-.• • •. >< - , ••
X
SDWIS/FED (Round 2)
20 Cross-Section
States (used in
comparison)
/
s
/
/
/
/
/
/
/
vr • .
15 Other States
(not used in
comparison)
.X
X
X
X
X
X
X
46
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
States/ Tribes/
Territories
Montana
North Carolina
North Dakota
Nebraska
New Hampshire
New Jersey ' *
•New Mexico' .
Nevada
New York
OMo
Oklahoma
Oregon
Pennsylvania
Puerto Rico
Rhode Island
South Carolina
South Dakota
Tennessee
Tribes
Texas
Utah
Virginia
Virgin Islands
Vermont
Washington
Wisconsin
West Virginia
Wyoming
States in Both
Round 1 and Round 2
URCIS (Round 1)
24 Cross-Section
States (used in
comparison)
/
^
-••. / .
•" / .' - '.
^
/
/
/
'.- . ••" /.
/
/
15
16 Other States
(not used in
comparison)
X
x
X
X
X
X
X
10
SDWIS/FED (Round 2)
20 Cross-Section
States (used in
comparison)
/
/
..../•
-.;./••
/
/
/
/
/
' .- . ' " / .
15
15 Other States
(not used in
comparison)
. X
X
X
X .
X
X
X
X
10
Highlighted States are common to both URCIS (Round 1) and SDWIS/FED (Round2).
j/- States with data of adequate quality, used for comparison.
X- States with poor or incomplete data, not used for comparison.
Bold States have data of adequate quality in both URCIS (Round 1) and SDWIS/FED (Round2) for comparison
In addition to the States that have data in both URCIS (Round 1) and SDWIS/FED (Round 2)
databases, a determination was made regarding actual PWSs that are common to both databases. Table
VI.D.2 illustrates the small percentage of systems common to both URCIS (Round 1) and SDWIS/FED
(Round 2). Thirty-one percent of all PWSs in URCIS (Round 1) are also in SDWIS/FED (Round 2),
while only 22% of all SDWIS/FED (Round 2) PWSs are common to both rounds. This is, in part,
because there are many more systems reporting analytical results in SDWIS/FED (Round 2) than in
URCIS (Round 1).
Michigan, for example, has only 139 systems in URCIS (Round 1), and 123 of those systems
(88%) are also in SDWIS/FED (Round 2). In SDWIS/FED (Round 2), Michigan has a total of 3,209
systems. Of these SDWIS/FED (Round 2) systems, only 123 (approximately 4%) are in URCIS (Round
1). The number of PWSs in Alaska are problematic because the PWSIDs from URCIS (Round 1) do not
match the PWSIDs in SDWIS/FED (Round 2). A few States do have a higher percentage of systems
common to both rounds. Kentucky, Maryland, Minnesota, New Mexico, and Ohio each have over 70%
of their total number of systems common to both URCIS (Round 1) and SDWIS/FED (Round 2).
Coincidently, these are five of the States used for the comparison of occurrence data in States common in
URCIS (Round 1) and SDWIS/FED (Round 2), which makes this analysis more representative for
comparison of the States for each contaminant.
47
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table VI.D.2. URCIS (Round 1) and SDWIS/FED (Round 2) - Reporting Data in Comparison of Public
Water Systems
States/ Tribes/
Territories
Alaska
Alabama
Arkansas
American Samoa
Arizona
California
Colorado
Connecticut
Washington, D.C.
Delaware
Florida
Georgia
Guam
Hawaii
Iowa
Idaho
Illinois
Indiana
Kansas
Kentucky
Louisiana
Massachusetts
Maryland
Maine
Michigan
Minnesota
Missouri
Marianna Islands
Mississippi
Montana
North Carolina
North Dakota
Nebraska
New Hampshire
New Jersey
New Mexico
Nevada
New York
Ohio
Oklahoma
Oregon
Pennsylvania
Puerto Rico
Rhode Island
South Carolina
South Dakota
Tennessee
Tribes
Texas
Utah
Virginia
Number of
Duplicate
PWSs
0
55
6
0
123
67
54
0
0
0
0
0
0
0
0
0
0
120
0
395
13
165
820
0
123
1,305
81
0
177
202
0
0
0
144
16
538
0
0
1,880
0
0
0
0
0
0
25
50
0
116
0
0
Number of PWSs in
URCIS
(Round 1)
748
152
6
0
973
4,167
60
0
1
13
855
1,165
0
127
1,002
0
1,307
415
0
525
13
220
998
0
139
1,565
85
0
206
565
298
0
214
201
1,551
617
10
357
2,657
0
0
0
0
0
0
335
306
0
124
430
0
% URCIS (Round
1) PWSs in
SDWIS/FED
(Round 2)
0%
36%
100%
0%
13%
2%
90%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
29%
0%
75%
100%
75%
82%
0%
88%
83%
95%
0%
86%
0%
0%
0%
0%
72%
1%
87%
0%
0%
71%
0%
0%
0%
0%
0%
0%
7%
16%
0%
94%
0%
0%
Number of PWSs in
SDWIS/FED (Round
2)
625
314
577
0
123
67
833
87
0
0
0
0
0
0
0
0
0
120
0
445
1,394
506
1,015
745
3,209
1,581
1,434
0
1,155
0
2,263
296
0
849
17
755
0
0
2,259
888
1,168
1,424
0
117
1,047
27
78
26
4,863
0
0
% SDWIS/FED
(Round 2) PWSs in
URCIS
(Round 1)
0%
18%
1%
0%
100%
100%
6%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
100%
0%
89%
1%
33%
81%
0%
4%
83%
6%
0%
15%
0%
0%
0%
0%
17%
94%
71%
0%
0%
83%
0%
0%
0%
0%
0%
0%
93%
64%
0%
2%
0%
0%
-------
EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
States/ Tribes/
Territories
Virgin Islands
Vermont
Washington
Wisconsin
West Virginia
Wyoming
TOTAL
Number of
Duplicate
PWSs
0
113
878
0
0
0
7,466
Number of PWSs in
URCIS
(Round 1)
3
133
992
0
139
145
23,819
% URCIS (Round
1) PWSs in
SDWIS/FED
(Round 2)
0%
85%
89%
0%
0%
0%
31%
Number of PWSs in
SDWIS/FED (Round
2)
0
636
2,680
225
0
0
33,848
% SDWIS/FED
(Round 2) PWSs in
URCIS
(Round 1)
0%
18%
33%
0%
0%
0%
22%
Comparisons of contaminants in URCIS (Round 1) and SDWIS/FED (Round 2) indicated that
there were no common lOCs (Group 1) or SOCs (Regulated or Group 2) reported in both databases. In
contrast, all of the unregulated Group 3 and Group 4 VOCs reported in SDWIS/FED (Round 2) were also
reported in URCIS (Round 1). None of the regulated VOCs reported in URCIS (Round 1), however,
were reported in SDWIS/FED (Round 2). Summary data for comparison of the two CCL VOCs
(hexachlorobutadiene and naphthalene) common to both URCIS (Round 1) and SDWIS/FED (Round 2)
data are presented in Appendix D (Tables D.I- D.2).
The tables in Appendix D contain similar summary data to Appendices A and B for the eight
States (with adequate data quality) common to both databases. The total number of analytical records
from URCIS (Round 1) to SDWIS/FED (Round 2) generally increased for all eight States and both
contaminants, with the exception of Kentucky. The number of total unique PWSs increased from URCIS
(Round 1) to SDWIS/FED (Round 2) for Minnesota, North Carolina, New Mexico and Washington,
while the number of PWSs decreased from Round 1 to Round 2 in Alaska, Kentucky, Maryland and Ohio
for the two contaminants.
Changes in the percentages of samples and percentage of PWSs with at least one analytical result
greater than the MRL followed no consistent pattern, by contaminant or by State. The percentage of
PWSs with at least one analytical result exceeding the concentration of the HRL (or 1A HRL) also
followed no apparent or consist pattern of change between URCIS (Round 1) and SDWIS/FED (Round 2)
data.
VI.E. Comparing Across Systems Types and Sizes
Data for select contaminants were also evaluated based on system type and size. Both the URCIS
(Round 1) and SDWIS/FED (Round 2) data were reviewed according to system type (community water
systems and non-transient non-community water systems) and further stratified by system size (based on
the five standard population-served categories). The summary data for these comparisons are presented
in Appendix E (Tables E.I - E.2 for results from URCIS (Round 1) and Tables E.3 - E.8 for results from
SDWIS/FED (Round 2)). These stratified occurrence findings allow an evaluation of any system size
patterns and also provide an indication of population exposure.
Generally, for both Round 1 and 2 data, the percentage of public water systems with analytical
results greater than the MRL and the HRL increases as the system size (population-served) increases.
Also, it appears that the percentage of public water systems with analytical results greater than the MRL
and the HRL is generally greater for community water systems than for non-transient non-community
water systems. Note that there is a much greater number of CWSs than NTNCWSs in the database.
VII. GRAPHICAL AND SPATIAL ASSESSMENTS OF CCL PRIORITY CONTAMINANTS
The URCIS (Round 1) and SDWIS/FED (Round 2) cross-section States used in the assessments
in this section are shown in Figures V.B.2 and VB.2.b, respectively. Most of the Section VII figures
(graphs and maps) present analytical results based on these cross-section States. Some figures (discussed
below) use additional State data to increase spatial coverage. All these graphical and spatial assessments
are conducted to provide additional analytical detail for the CCL priority contaminants. All these
graphical and spatial assessments, evaluated together with the analytical results tables presented
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
throughout this report (and report appendices), serve to develop a comprehensive overview of the degree,
distribution, and temporal trends (if any) of contaminant occurrence.
One important aspect of the cross-section State data must be considered as part of any
conclusions drawn from the maps and graphs in this report. The development of the nationally
representative cross-sections were discussed for URCIS (Round 1) and SDWIS/FED (Round 2) data in
Section V. These national cross-sections are developed from public water systems' contaminant
monitoring data with the intent that, in aggregate, the cross-section States' occurrence findings are
indicative of national occurrence. (Various occurrence comparisons between the URCIS and
SDWIS/FED data, as well as comparisons to other State data sets, indicate that these cross-section States
do provide contaminant occurrence data that are reasonable indications of national occurrence.)
Therefore, although sub-national occurrence findings, such as regional or multi-State occurrence
patterns, can be valid and useful for these initial assessments, any regional occurrence patterns (or
absence of patterns) should be considered in the context of the source and coverage of the State cross-
section data. With half (or more) of the States without adequate data (and therefore not in the cross-
sections used for analyses), regional patterns may be difficult to characterize and must be interpreted with
caution. Supplemental information should be collected and used, whenever possible, to assist in
evaluating the significance of any apparent regional patterns. For example, when assessing a particular
pesticide occurrence pattern in this report, supplemental State or regional pesticide use information could
be reviewed to determine how the possible absence of a pesticide high-use State might affect
interpretation of any occurrence pattern in the cross-section State maps.
The NIRS survey was designed to provide a single national occurrence assessment. This survey
is based on significantly less data than that provided by URCIS or SDWIS/FED. The NIRS survey
results should only be reviewed in aggregate (i.e., at the national level and not at any regional or State
level); therefore, no maps or graphs using the NIRS data for manganese or sodium are included.
Only SDWIS/FED (Round 2) data are available for aldrin, dieldrin, metribuzin, and sulfate. Both
URCIS (Round 1) and SDWIS/FED (Round 2) data are available for hexachlorobutadiene, and
naphthalene. The figures developed in this section of the report reflect this data availability.
Most of the figures below that illustrate distribution of occurrence must be based on non-biased
data; for these figures only the cross-section State data are used to develop the maps and graphs.
However, to increase the spatial coverage of the figures that broadly identify contaminant occurrence
(Figures VILA. 1,VII.B. 1, and so on through VII.F. 1), all data from all States with data in URCIS (Round
1) and SDWIS/FED (Round 2) are used. Therefore, in these figures the data from cross-section States are
included, as are data from the non-cross-section States (i.e., States with limited or biased data). This more
extensive use of the data in the databases can be appropriate when a simple 'yes or no' identification of
States with any PWS contaminant detection is of interest.
VILA. Aldrin
Some general comments can be made about the occurrence of aldrin. Aldrin detections appear to
be limited to States south of a line extending between New Mexico and Massachusetts; see Figure
VILA. 1 (this map includes information from cross-section and non-cross-section States). Five out of 27
States with aldrin data had at least one public water system with at least one analytical detection of aldrin.
In Figure VII.A.2 (based on cross-section States only), both maps (relative to the MRL in the upper map
and to the HRL in the lower map) reflect this same apparent distribution. However, note the number of
agricultural States with no aldrin occurrence data. (Use of supplemental data such as aldrin use, or State
or regional occurrence studies could perhaps complement the cross-section results presented here.) In
Figure VILA.3, a possible downward annual trend in aldrin occurrence is suggested. (However, 1992 is
the overlap year between Round 1 and Round 2 monitoring, so some occurrence effects critically based
on 1992 may have resulted from the changing monitoring and reporting requirements between Rounds 1
and 2.)
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.A.l. Detections of Aldrin - SDWIS/FED (Round 2) Data (including Cross-Section and non-
Cross-Section States)
SDWIS/FED (Round 2) States
] States not in SDWIS/FED
1 No data for Aldrin
1 States with No Detections (No PWSs > MRL)
I States with Detections (Any PWSs > MRL)
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.A.2. Distribution of Aldrin Occurrence - SDWIS/FED (Round 2) Cross-Section State Data
SDWIS/FED (Round 2) Cross-Section States
o
* State of Massachusetts is an outlier with 17.86% PWSs > MRL
Aldrin Occurrence relative to the MRL
States not in Cross-Section
No data for Aldrin
?. 1 0.00% PWSs > MRL
0.01- 1.00% PWSs > MRL
>1.00%PWSs>MRL*
SDWIS/FED (Round 2) Cross-Section States
Aldrin Occurrence relative to the HRL
| | States not in Cross-Section
No data for Aldrin
I. -> "| 0.00% PWSs > HRL
0.01- 1.00% PWSs > HRL
> 1.00% PWSs > HRL
52
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.A.3. Aldrin Occurrence By Year - SDWIS/FED (Round 2) Cross-Section State Data
Percent PWS>MRL
i n% -,
n 8%
n £,%
n zi%
n oo/
0 0% -
™-.,.
1992 1993
/'~
1994
1995 1996 1997
Percent PWS>HRL
i n% ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
n n%
1992 1993
~±.
1994
1995 1996 1997
Note: All systems with analytical detections also exceeded the concentration value of the HRL.
Note for 1992: A relatively low number of systems were sampled in 1992, which may contribute to the high rates of occurrence.
The Health Reference Level (HRL) used for Aldrin is 0.002 (ig/L. This HRL is a draft value for working review only.
53
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
VII.B. Dieldrin
Dieldrin detections appear to be of a similar pattern to that of the related pesticide aldrin, with
detections limited to States south of a line extending between Texas and Massachusetts (see Figure
VII.B.1). Eight out of 27 States with dieldrin data had at least one public water system with at least one
analytical detection of dieldrin. In Figure VII.B.2, both maps (relative to the MRL in the upper map and
to the HRL in the lower map) reflect this same apparent distribution. However, note the number of
agricultural States with no dieldrin occurrence data. In Figure VII.B.3, a possible downward annual trend
in dieldrin occurrence is suggested. (However, 1992 is the overlap year between Round 1 and Round 2
monitoring, so some occurrence effects critically based on 1992 may have resulted from the changing
monitoring and reporting requirements between Rounds 1 and 2.)
Figure VII.B. 1. Detections of Dieldrin - SDWIS/FED (Round 2) Data (including Cross-Section and non-
Cross-Section States)
SDWIS/FED (Round 2) States
Dieldrin Detections
1 States not in SDWIS/FED
] No data for Dieldrin
] States with No Detections (No PWSs > Detection Limit)
I States with Detections (Any PWSs > Detection Limit)
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.B.2. Distribution of Dieldrin Occurrence - SDWIS/FED (Round 2) Cross-Section State Data
SDWIS/FED (Round 2) Cross-Section States
Dieldrin Occurrence relative to the MRL
States not in Cross-Section
No data for Dieldrin
0 00% PWSs > Detection Limit
0.01- 1.00% PWSs > Detection Limit
1.00% PWSs > Detection Limit *
SDWIS/FED (Round 2) Cross-Section States
o
Dieldrin Occurrence relative to the HRL
| | States not in Cross-Section
| | No data for Dieldrin
\~~\ 0 00% PWSs > HRL
0.01 - 1.00% PWSs > HRL
1.00% PWSs > HRL
55
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.B.3. Dieldrin Occurrence By Year - SDWIS/FED (Round 2) Cross-Section State Data
l.CP/0
Q8P/o
0.6%
0.4%
0.2%
0.0%
1992
Percent PV\5s>lVKL
1993
1994
1995
1996
1997
1.0%
0.8%
0.6%
0.4%
0.2%
0.0%
Percent PWSs>HRL
1992
1993
1994
1995
1996
1997
Note: All systems with analytical detections also exceeded the concentration value of the HRL.
Note for 1992: The high rates of occurrence are related to the low number of systems sampled in 1992.
The Health Reference Level (HRL) used for Dieldrin is 0.002 (ig/L. This is a draft value for working review only.
56
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
VII.C. Metribuzin
Metribuzin detections appear to be relatively few, and with no particular geographic pattern (see
Figure VII.C. 1.). Only three out of 24 States with metribuzin data had at least one public water system
with at least one analytical detection of metribuzin. In Figure VII.C.2., both maps (relative to the MRL in
the upper map and to the HRL in the lower map) reflect this same apparent very limited distribution when
using data from only the cross-section States. This low occurrence is evidenced in the lower map of
Figure VII.C.2., where there are no public water systems in any of the cross-section States with analytical
results exceeding the concentration value of the metribuzin HRL. (Again note, however, the number of
agricultural States with no metribuzin occurrence data available for this occurrence evaluation.) In Figure
VII.C.3, a very tentative downward annual trend in metribuzin occurrence is possibly suggested.
Figure VII.C.l. Detections of Metribuzin - SDWIS/FED (Round 2) Data (including Cross-Section and
non-Cross-Section States)
SDWIS/FED (Round 2) States
Metribuzin Detections
] States not in SDWIS/FED
1 No data for Metribuzin
1 States with No Detections (No PWSs > MRL)
I States with Detections (Any PWSs > MRL)
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.C.2. Distribution of Metribuzin Occurrence - SDWIS/FED (Round 2) Cross-Section State
Data
SDWIS/FED (Round 2) Cross-Section States
* State of Massachusetts is an outlier with 14.29% PWSs > MRL
Metribuzin Occurrence relative to the MRL
States not in Cross-Section
No data for Metribuzin
«H 000% PWSs > MRL
0.01- 1.00% PWSs > MRL
> 1.00% PWSs > MRL*
SDWIS/FED (Round 2) Cross-Section States
Metribuzin Occurrence relative to the HRL
States not in Cross-Section
No data for Metribuzin
000%PWSs>HRL
0.01- 1.00% PWSs > HRL
1.00% PWSs > HRL
58
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.C.3. Metribuzin Occurrence By Year - SDWIS/FED (Round 2) Cross-Section State Data
l.CP/0-
U/f/o-
U.Z/o-
nrp/ -
Percent PV\S> MRL
1992 1993
- -,™r™
1994 1995 1995 1997
Note for 1992: The high rates of occurrence are related to the low number of systems sampled in 1992.
The Health Reference Level (HRL) used for Metribuzin is 91 (ig/L. This HRL is a draft value for working review only.
There are no PWSs with analytical results exceeding the concentration value of the HRL for Metribuzin in SDWIS/FED (Round 2).
VII.D. Sulfate
Sulfate is of a distinctly different occurrence character than the three previously discussed SOCs.
Occurrence is generally widespread, but appears to be concentrated in the eastern and southern portions
of the US (see Figure VII.D. 1., which includes all States, both cross-section and non-cross-section States,
with data in SDWIS/FED). Twenty out of 21 States with PWS sulfate data in SDWIS/FED (Round 2)
had at least one public water system with at least one analytical detection of sulfate. In the Figure
VII.D.2. cross-section State maps, both the upper map (regarding occurrence relative to the MRL) and the
lower map (with occurrence relative to the HRL) reflect this same general occurrence distribution. In the
upper map of Figure VII.D.2., 14 out of the 20 cross-section States reported more than 70% of PWSs with
at least one detection of sulfate. The lower map of Figure VII.D.2. suggests that, in addition to being
widespread, occurrence is also somewhat high. Four out of the 20 cross-section States reported between
2% and 5.5% of PWSs with at least one analytical detections above the HRL of 500,000 (ig/L. Two
temporal trends of sulfate occurrence are readily apparent in the graphs in Figure VII.D.3. While the
percent of PWSs with at least one sample greater than the MRL has increased from 1992 to 1997 (in the
upper graph), the percent of PWSs with at least one sample greater than the HRL (of 500,000 (ig/L) has
slightly, but steadily, decreased over the same period (in the lower graph).
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.D.l. Detections of Sulfate - SDWIS/FED (Round 2) Data (including Cross-Section and non-
Cross-Section States)
SDWIS/FED (Round 2) States
States not in SDWIS/FED
No data for Sulfate
States with No Detections (No PWSs > MRL)
States with Detections (Any PWSs > MRL)
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.D.2. Distribution of Sulfate Occurrence - SDWIS/FED (Round 2) Cross-Section State Data
SDWIS/FED (Round 2) Cross-Section States
Sulfate Occurrence relative to the MRL
States not in Cross-Section
No data for Sulfate
0.00% PWSs > MRL
70.00 - 85.00% PWSs > MRL *
85.00 - 100.00% PWSs > MRL
SDWIS/FED (Round 2) Cross-Section States
o
Sulfate Occurrence relative to the HRL
States not in Cross-Section
No Data for Sulfate
000%PWSs>HRL
0.01-2.00% PWSs > HRL
2.00-5.50% PWSs > HRL
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.D.3. Sulfate Occurrence By Year - SDWIS/FED (Round 2) Cross-Section State Data
Percent PV\S>]V«L
mv _^~~~~~~~---~---~-----~~~~~~~~~~~~~^^
-
nrp/n
'•^~
1992 1993 1994 1995 1995 1997
4.0% -
3.0% -
2.0% -
1.0% -
0.0% -
Percent PWS>HRL
1992 1993 1994 1995 1996 1997
The Health
Reference Level (HRL) used for this Sulfate occurrence assessment is 500,000 (ig/L. An aggregate sulfate occurrence (for all years combined)
relative to an alternative HRL of 1,000,000 (ig/Lis included in Table VLB. 1. These HRLs are draft values for working review only.
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
VILE. Hexachlorobutadiene
There are PWS occurrence data for hexachlorobutadiene (and naphthalene) in both URCIS
(Round 1) and SDWIS/FED (Round 2) data. Therefore, additional occurrence maps can be constructed to
provide a somewhat broader picture of occurrence. Hexachlorobutadiene appears to be of fairly
widespread occurrence, though its occurrence does not appear to have a distinct geographic pattern (see
Figure VII.E. 1., which includes all States, both cross-section and non-cross-section States, from both the
URCIS and SDWIS/FED databases). Nineteen out of 41 States with PWS hexachlorobutadiene data in
URCIS (Round 1) and SDWIS/FED (Round 2) had at least one public water system with at least one
analytical detection of hexachlorobutadiene.
In Figure VII.E.2., occurrence relative to the MRL is presented for the URCIS cross-section
States in the upper map and the SDWIS/FED cross-section States in the lower map. Generally, the maps
reflect hexachlorobutadiene's broad occurrence.
In Figure VII.E.3., the URCIS and SDWIS/FED cross-section States are combined to provide a
broad coverage, illustrating occurrence relative to the MRL in the upper map and to the HRL in the lower
map. In the upper map, 18 out of 33 cross-section States have at least one PWS with an analytical
detection of hexachlorobutadiene. And in the lower map, eight out of 33 cross-section States have at least
one PWS with a sample analytical result greater than the HRL.
Hexachlorobutadiene occurrence over time is presented in Figures VII.E.4. and VII.E.5. The
data used in these two figures are from the eight States that had hexachlorobutadiene occurrence data in
both URCIS and SDWIS/FED databases. In both figures, occurrence is measured relative to the MRL in
the upper graph and relative to the HRL in the lower graph. In Figure VII.E.4., the graphs suggest some
annual variability in occurrence. When discounting the Round 1 and Round 2 overlap year of 1992, there
appears to be no definite temporal trend in hexachlorobutadiene occurrence from 1984 to 1997 (most of
the occurrence data are from 1988 to 1997). Overall, occurrence is quite low. In Figure VII.E.5, there
appears to be no apparent pattern of hexachlorobutadiene occurrence between Round 1 and Round 2.
Figure VII.E.l. States with PWSs with detections of Hexachlorobutadiene for all States (including
Cross-Section and non-Cross-Section States) with data in URCIS (Round 1) and SDWIS/FED (Round 2)
All URCIS (Round 1) and SDWIS/FED (Round 2) States
Hexachlorobutadiene Detections
States not in URdS or SDWIS/FED
No data for Hexachlorobutadiene
States with No Detections (No PWSs > MRL)
States with Detections (Any PWSs > MRL)
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.E.2. States with PWSs with detections of Hexachlorobutadiene for Round 1 (above) and
Round 2 (below) Cross-Section States
URCIS (Round 1) Cross- Section States
Hexachlorobutadiene Occurrence
relative to the MRL
| | States not in Cross-Section
| | No data for Hexachlorbutadiene
E—j 0.00% PWSs > MRL
0.01 - 1.00% PWSs > MRL
1.00 - 3.50% PWSs > MRL*
SDWIS/FED (Round 2) Cross- Section States
o
Hexachlorobutadiene Occurrence
relative to the MRL
| | States not in Cross-Section
| | No data for Hexachlorbutadiene
[731000%PWSs>MRL
0.01 - 1.00% PWSs > MRL
1.00-3.50% PWSs > MRL
64
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.E.3. Round 1 and Round 2 Cross-Section States with PWSs with Hexachlorobutadiene
detections (upper map) and with concentrations above the Health Reference Level (lower map)
URCIS (Round 1) and SDWIS/FED (Round 2) Cross-Section States
Hexachlorobutadiene Occurrence
realtive to the MRL
| | States not in Cross-Section
| | No data for Hexachlorbutadiene
mOQO%PWSs>MRL
ROT 0.01 - 1.00% PWSs > MRL
HI 1.00-3.50% PWSs > MRL*
URCIS (Round 1) and SDWIS/FED (Round 2) Cross-Section States
o
"State of Florida is an outliernith 5.36% PWS > HRL
Hexachlorobutadiene Occurrence
relative to the HRL
| | States not in Cross-Section
| | No data for Hexachlorobutadiene
[^JOOO%PWSS>HRL
0.01 - 1.00% PWSs > HRL
Bill 1.00-3.50% PWSs > HRL*
65
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.E.4. Hexachlorobutadiene Occurrence By Year (1984 - 1997) for Select Cross-Section States
0.0%
1984 1985 1986 1987 1988 1989 1990 1991 1992 1992 1993 1994 1995 1996 1997
0.14%
0.12%
0.10%
0.04%
0.02%
0.00%
I
1987 1988 1989 1990 1991 1992 1992 1993 1994 1995 1995 1997
Summary statistics by year are from 8 States: AK, KY, MD, MN, NC, NM, OH and WA. These are the only Cross-Section States with PWS
hexachlorobutadiene data in both URCIS (Round 1) and SDWIS/FED (Round 2).
The Health Reference Level (HRL) used for Hexachlorobutadiene is 0.9 (ig/L. This is a draft value for working review only.
There are data for 1992 in both URCIS (Round 1) and SDWIS/FED (Round 2).
66
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.E.5. Occurrence of Hexachlorobutadiene By State - URCIS (Round 1) and SDWIS/FED
(Round 2) for Select Cross-Section States
Percent PV\5s>lVKL
AKKY1VD1VNNCNV1CHWA
DROUND1 •ROUND2
n HQO/^ _,
n fKo/,
n nd.% -
n no% _
n rvw
AK KY
Percent PV\Ss>HRL
MD MN NC
DROUND1 • ROUND 2
NM
C
H WA
The Health Reference Level (HRL) used for Hexachlorobutadiene is 0.9 (ig/L. This is a draft value for working review only.
These are the only Cross-Section States with PWS hexachlorobutadiene data in both URCIS (Round 1) and SDWIS/FED (Round 2).
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VILE Naphthalene
Data availability for naphthalene in both URCIS (Round 1) and SDWIS/FED (Round 2) data
enable development of additional occurrence maps to provide a somewhat broader picture of occurrence.
Naphthalene appears to be of very widespread occurrence, though its occurrence does not appear to have
a distinct geographic pattern (see Figure VII.F. 1., which includes all States, both cross-section and non-
cross-section States, from both the URCIS and SDWIS/FED databases). Thirty-two out of 43 States with
PWS naphthalene data in URCIS (Round 1) and SDWIS/FED (Round 2) had at least one public water
system with at least one analytical detection of naphthalene.
In Figure VII.F.2., occurrence relative to the MRL is presented for the URCIS cross-section
States in the upper map and the SDWIS/FED cross-section States in the lower map. Generally, the maps
reflect naphthalene's broad occurrence. In the upper map, 18 out of 22 URCIS (Round 1) States with
naphthalene data have at least one PWS with at least one analytical detection (a sample analytical result
greater than the MRL). In the lower map, 16 out of 20 SDWIS/FED (Round 2) States with naphthalene
data have at least one PWS with at least one analytical detection (a sample analytical result greater than
the MRL).
In Figure VII.F.3., the URCIS and SDWIS/FED cross-section States are combined to provide a
broad coverage, measuring occurrence relative to the MRL in the upper map and to the HRL in the lower
map. Though naphthalene, like hexachlorobutadiene, is of widespread occurrence, the characteristic of its
occurrence is different. While naphthalene detections (sample analytical results greater than the MRL)
are found in many States, naphthalene sample analytical results greater than the HRL (higher levels of
occurrence) are uncommon. Twenty-seven out of 34 States have at least one PWS with at least one
analytical detection (in the upper map of Figure VII.F.3.). In contrast, only one State out of 34 has at
least one PWS with an analytical detection of naphthalene greater than the HRL.
Naphthalene occurrence overtime is presented in Figures VII.F.4. and VII.F.5. The data used in
these two figures are from the eight States that had naphthalene occurrence data in both URCIS and
SDWIS/FED databases. In both figures, occurrence is measured relative to the MRL. In Figure VII.F.4.,
the graph suggests annual variability in occurrence, though no clear temporal trend is defined. In Figure
VII.F.5, there might be an indication that detections of naphthalene are more common in Round 2 than in
Round 1. While three States exhibit either the same number of or fewer PWSs with detections in Round
2, five of the eight States with data in both rounds exhibit an increase in the number detections from
Round 1 to Round 2. Although a temporal trend is suggested here, note that this is based on only eight
States that may or may not be representative of all States.
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EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.F.l. States with PWSs with detections of Naphthalene for all States (including Cross-Section
and non-Cross-Section States) with data in URCIS (Round 1) and SDWIS/FED (Round 2)
All URCIS (Round 1) and SDWIS/FED (Round 2) States
Naphthalene Detections
B States not in URCIS
No data for Naphthalene
States with No Detections (No PWSs > MRL)
States with Detections (Any PWS > MRL)
69
-------
EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.F.2. States with PWSs with detections of Naphthalene for Round 1 (above) and Round 2
(below) Cross-Section States
URCIS (Round 1) Cross-Section States
Naphthalene Occurrence
relative to the MRL
S States not in Cross-Section
No data for Naphthalene
000°oPWSs>MRL
0.01- 1.00% PWSs > MRL
1.00 - 4.00% PWSs > MRL*
SDWIS/FED (Round 2) Cross-Section States
Naphthalene Occurrence
relative to the MRL
| | States not in Cross-Section
| | No data for Naphthalene
F3 0 00% PWSs > MRL
0.01 - 1.00% PWSs > MRL
1.00 - 4.00% PWSs > MRL*
70
-------
EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.F.3. Round 1 and Round 2 Cross-Section States with PWSs with Naphthalene detections
(upper map) and with concentrations above the Health Reference Level (lower map)
URCIS (Round 1) and SDWIS/FED (Round 2) Cross-Section States
* Outliers: State of Alabama at 28.3%; State of Florida at 7.0%; State of New Hampshire at 1
Naphthalene Occurrence
relative to the MRL
II States not in Cross-Section
[^^ No data for Naphthalene
F—1 0.00% PWSs > MRL
0.01 - 1.00% PWSs > MRL
Bill 1.00 - 4.00% PWSs > MRL*
URCIS (Round 1) and SDWIS/FED (Round 2) Cross-Section States
Naphthalene Occurrence
relative to the HRL
| | States not in Cross-Section
| | No data for Naphthalene
l~~loOO%PWSs>HRL
0.01 - 1.00% PWSs > HRL
1.00 - 4.00% PWSs > HRL
71
-------
EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Figure VII.F.4. Naphthalene Occurrence By Year (1984 - 1997) from Select Cross-Section States
Percent PWSs > MRL
1.2%
1.0%
0.6%
0.4%
0.2%
0.0%
1984 1985 1986 1987 1988 1989 1990 1991 1992 1992 1993 1994 1995 1996 1997
Summary statistics by year are from 8 States: AK, KY, MD, MN, NC, NM, OH and WA. These are the only Cross-Section States with PWS
naphthalene data in both URCIS (Round 1) and SDWIS/FED (Round 2). There are data for 1992 in both URCIS (Round 1) and SDWIS/FED
(Round 2).
Figure VII.F.5. Occurrence of Naphthalene By State - URCIS (Round 1) and SDWIS/FED (Round 2)
Percent PWSs > MRL
AK KY MD MN NC NM
DROUND 1 •ROUND 2
OH WA
The Health Reference Level (HRL) used for Naphthalene is 140 (ig/L. This is a draft value for working review only.
There are no PWSs with analytical results exceeding the concentration value of the HRL for Naphthalene for these 8 States in URCIS (Round 1)
or SDWIS/FED (Round 2). These are the only Cross-Section States with PWS naphthalene data in both URCIS and SDWIS/FED.
72
-------
EPA - OGWDW Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
REFERENCES
Squillace, P.J., M.J. Moran,W.W. Lapham, C.V. Price, R.M. Clawges, and J.S. Zogorski. 1999.
"Volatile Organic Compounds in Untreated Groundwater of the United States, 1985-
1995." Environ. Sci. Technol. v.33, no. 23, pp. 4176-4187.
U.S. Department of Commerce (USDOC), Bureau of the Census. 1994. 1992 Census of Agriculture.
Washington, B.C.: U.S. Government Printing Office.
USDOC, Bureau of the Census. 1996. 1992 Census of Manufactures. Washington, B.C.:
U.S.Government Printing Office.
USDOC, Bureau of the Census. 1997. 1995 Annual Survey of Manufactures. Washington, D.C.: U.S.
Government Printing Office.
U.S. Environmental Protection Agency (USEPA). 1999. A Review of Contaminant Occurrence in
Public Water Systems. EPA Report # 816-R-99-006, Office of Water, 78 pp.
USEPA. 2001. TRI Explorer (Data from 1988-1995). Available on the Internet at:
http://www.epa.gov/triexplorer/chemical.htm (Last modified October 4, 2001).
73
-------
APPENDICES
ANALYSIS OF NATIONAL OCCURRENCE OF THE 1998 CONTAMINANT
CANDIDATE LIST (CCL) REGULATORY DETERMINATION PRIORITY
CONTAMINANTS IN PUBLIC WATER SYSTEMS
-------
Notes to Accompany Appendix Tables
The following tables present a summary of the analytical results and occurrence for the listed
contaminants. The various measures and descriptive statistics shown on the tables include:
Total # Samples = the total number of analytical records for the contaminant in the state (or in the
portion of the data indicated)
Total Unique PWS = the total number of public water systems with records for the contaminant in the
state (or in the portion of the data indicated)
Minimum Value = the minimum analytical value of all analytical results for the contaminant in the state
dataset (or in the portion of the data indicated)
99th Value = the concentration value of the 99th percentile of all analytical results for the contaminant in
the state dataset (or in the portion of the data indicated)
Maximum Value = the maximum analytical value of all analytical results for the contaminant in the state
dataset (or in the portion of the data indicated)
Minimum Detects = the minimum analytical value of all the detections (analytical results greater than
the Minimum Reporting Level) for the contaminant in the state dataset (or in the portion of the
data indicated)
Median Detects = the median analytical value of all the detections (analytical results greater than the
Minimum Reporting Level) for the contaminant in the state dataset (or in the portion of the data
indicated)
% PWS > MRL = percent of the total number of public water systems with at least one analytical result
that exceeded the Minimum Reporting Level
% PWS > 1A HRL = percent of the total number of public water systems with at least one analytical
result that exceeded half the Health Reference Level
% PWS > HRL = percent of the total number of public water systems with at least one analytical result
that exceeded the Health Reference Level
Total = the total number of samples, unique PWSs, and percent PWSs exceeding the MRL, 1A HRL, or
HRL are the summation of all values for all the states for the contaminant; i.e. Total = all data
from 40 states/territories; 24 States = all data from cross-section of 24 states. The values
indicated as "totals" for the analytical results, e.g. minimum value, 99th percentile value, etc., are
similarly the value derived from the data from all states, or 24 states respectively.
Concentration values for URCIS (Round 1) data and SDWIS/FED (Round 2) data are measured in
micrograms per liter (• g/L).
Concentration values for NIRS data are measured in milligrams per liter (mg/L).
-------
APPENDICES
Appendix A.
Appendix B.
Appendix C.
Appendix D.
Appendix E.
URCIS (Round 1) Data Summary for 2 CCL
Contaminants
SDWIS/FED (Round 2) Data Summary for 6 CCL
Contaminants
NIRS Data Summary for 2 CCL Contaminants
Comparison of URCIS (Round 1) Data to SDWIS/FED
(Round 2) Data for Select States and Select Contaminants
Summary Data for URCIS (Round 1) and SDWIS/FED
(Round 2) for Select Contaminants by System Type and
Population Served
-------
Appendix A. URCIS (Round 1) Data Summary for 2 CCL Contaminants
Table A. 1 .a UCM (1987) Data - Hexachlorobutadiene Occurrence in Public Water Systems
Table A.l.b UCM (1987) Data - Hexachlorobutadiene Occurrence in Public Water Systems
Based on Number of Samples
Table A. 1 .c UCM (1987) Data - Hexachlorobutadiene Occurrence in Public Water Systems
Based on Number of Systems
Table A.2.a UCM (1987) Data - Naphthalene Occurrence in Public Water Systems
Table A.2.b UCM (1987) Data - Naphthalene Occurrence in Public Water Systems -
Based on Number of Samples
Table A.2.c UCM (1987) Data - Naphthalene Occurrence in Public Water Systems -
Based on Number of Systems
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table A. 1.a URCIS (Round 1) Data- Hexachlorobutadiene Occurrence in Public Water Systems
STATE
AK
AL
AR
AZ
CA
CO
DC
DE
EI-
SA
HI
IA
IL
IN
KY
LA
MA
MD
Ml
MN
MO
MS
MT
NC
NE
NH
NJ
NM
NV
NY
OH
5D
TN
TX
UT
VI
VT
WA
wv
WY
TOTAL
SfSTATES
TOTAL
UNIQUE
PWS
665
131
448
585
6
1
10
112
12,7
21,3
357
524
13
8i3
1,553
85
28?
/KM
580
8
356
2,655:
335
303
2
4-11
3
882
57
14§
12,768
12,284
# GW PWS
540
93
407
571
3
0
8
,-'7
1.12
148
321
281
8
,,-836
,1,528
71
,,-254
,780
555
7
252
2,483,
306
156
2
381
0
,,'83?
26
1J.6
1 1 ,332
10,880
# SW PWS
130
42
47
2*
4
^
2
105'
16
64
37
233
4
50
28
14
44
11
35'
2
123
1.66
28
147
0
34
3
77
31-'
38
1,538
1,388
% PWS
>MRL
J.5Q%
3,05%
0,88%
0,00%
0.00%
0.00%
0.00%
5,36%
0.00%
0,47%
0,00,%
0,00,%
0.00%
0,10,%
0,00%
0.00%
0,00%
0,75%
0,00,%
0.00%
0.28%
0,11%
0,30%
0,33%
100.00%
J,22%
0.00%
0,10,%
0,00,%
0,00,%
0.36%
0,35%
% GW PWS
>MRL
1.48%
4,30%
0,74%
0,00%
0.00%
0.00%
0.00%
0,00%
0,Qfi%
0,67%
0,00%
0,00%
0.00%
OJ1%
0,00%
0.00%
0,00%
0,76%
0,00%
0.00%
0.40%
OJ2%
0.33%
0,64%,
100.00%
1.02%
0.00%
0,31%
0,00%
0,00%
0.32%
0.30%
% SW PWS
>MRL
,1.54%
0.00%
2,13%
0.00%
0.00%
0.00%
0.00%
5,71,%
,0,00%
,0,00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
,,'0,00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
2.84%
0.00%
0.00%
0.00%
0.00%
0.65%
0,72%
% PWS
>HRL
OflO%
1,53%
022%
0,00%
0.00%
0.00%
0.00%
5t36%-
,,'0,00%
,,'0,00%
0,00%
0,00%
0.00%
0,00%
0,00%
0.00%
,,0,00%
0:2,5%
0,00%
0.00%
0.28%
0,08%
0,00%
0,33%
100.00%
0,00%
0.00%
0,00%
0,00%
0,00%
0.12%
o.y%
% GW PWS
>HRL
0.00%
2.J5%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
o.oq%
0.00%
0.00%
0.00%
0.00%
0.00%
0,00%
0,25%
0,00%
0.00%
0.40%
0.08%
0.00%
0.64%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.07%
0,06%
% SW PWS
>HRL
0,00%
0,00%
2,1,3%
0,00%
0.00%
0.00%
0.00%
5:71%
0,00%
0,QQ,%
0,00%
0,00%
0.00%
0,00%
0,00%
0.00%
0,00%
0,00%
0,00%
0.00%
0.00%
0,00%
0,00%
0,00%
0.00%
0,00%
0.00%
0,00%
0,00%
0,00%
0.46%
0,51%
99% VALUE
(ijg/L)
< OsOO
0.50
< 2,00
< 6.00
< 0.64
< 0.50
< 0.50
5,00
< --0.30
< '2.00
< ,2,00
< 1,00
< 0.50
< 0,50
< 0,50
< 20.00
< 0,50
< ,1,20
< 1.00
< 0.20
< 5.00
< 2,00
< 0,50
< 0,50
8.00
< 5,00
< 1.00
< 0,50
< 4,00
< '2.00
< 5.00
< 5,00
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting
Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Hexachlorobutadiene is 0.8 ug/L. This is a draft value for working review only.
The highlighted States are part of the URCIS 24 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table A.1 .b URCIS (Round 1) Data- Hexachlorobutadiene Occurrence in Public Water Systems- Based on Number of Samples
STATE
AK
AL
AR
AZ
GA
CO
DC
DE
FL
6A
HI
IA
IL
IN
KY
LA
MA
MD
Ml
MN
MO
MS
MT
NC
NE
NH
NJ
NM
NV
NY
OH
SD
TN
TX
UT
VI
VT
WA
VW
WY
TOTAL
24 STATES
TOTAL
UNIQUE
PWS
885
131
4*
585'
6
1
10
1-12
127
2)3
35?
524
13
,,-983
85
29J
/801
590
8
356
,,8,655
335
,303
2
fl1
3
,-992
5?
148
12,768
12,284
TOTAL #
SAMPLES
1/45
351
1,104'
,,-2,005
9
48
53
1,30
1,221
/28
,4,889
2,878
22
,4,,?50
/S.S54
323
544'
1,830
1.595
148
2,095
16,95)
444
,-1,220
2
1,233
10
3.-9B7
189
my
45,549
42,839;
#GW
SAMPLES
1,480
,-244
940
1,949
5
0
44
10,
1,081
485
A488
A3 18
18
1,378
2,588
297
589'
1,443
1,4.75
136
1,560
1-5,038
383
,433
2
1,128
0
3,858
84
25»
39,246
37.-184
#SW
SAMPLES
285
107
,464
56
4
48
9
120
140
243
403
,-957
4
374
88
26
,75
1«7
120
12
535
,-913
,-81
/f?
0
1B5
10
331
/1 06
/54
6,303
5.Q55
% TOTAL
SAMPLES
>MRL
0.83%
1,-14%
0,83%:
0,00%'
0.00%
0.00%
0.00%
162*
0,00%
0.65%
0,00%
0.00%
0.00%
Q.08"/i
0,00%*
0.00%
0.00%'
0.37%'
000%
0.00%
0.05%
0.02%-
O23»
,,-0,Q8»
100.00%
0:73%;
0.00%
0.03%
0.00%;
0.00%
0.13%
O.J3%
%GW
SAMPLES
>MRL
0,81%
,4,,8frMRL
o.jsn
0.00%
,^.44%
0.00%
0.00%
0.00%
0.00%
,,-e.oo"/4
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0,00%
0.00%
0,00%
0.00%
0,00%
0.00%
0.00%
0,00%
0.00%
0.00%
0.00%
0.96%
0.00%
0.00%
0,00%
0.00%
0.21%
0.23*1
MIN VALUE
(M9/L)
< 0,00
< 0,50
,< 0.05'
< ooq.
< 0.00
< 0.50
< 0.40
< 0,00
,,x 0,00,
< 0,05
< 0,09
< 0.50
< 0.50
< 0,10
,< 0.60
< 0.20
« 0.60
,,x 0.00
< 0.00
< 0.20
< 0.11
,,< 0.20
< 0.18
< 0,02
6.00
,« 0.10
< 1.00
< 0.60
< 0.50
,« 0.80,
< 0.00
< .-0,00
99% VALUE
(M9/L)
< 0,00
0,60
,* 2.00'
< 8.00
< 0.64
< 0.50
< 0.50
6.00
,,< 0.30
< 2.00
< 2.00
< 1,00
< 0.50
< 0,50
,.f 0,50
< 20.00
* 0,50'
,,< 1.20
< 1.00
< 0.20
< 5.00
,,x 2.0O
< 0.50
< 0,50
8.00
,,< 6.00'
< 1.00
< 0,50
< 4.00
2,00
< 5.00
* 5,00
MAX VALUE
(M9/L)
0.30
1.00
,40.00'
< ,10.00
< 0.64
< 0.50
< 0.50
10.00
,,< 0.30
047
< 5,00
< 1.00
< 0.50
O.)0
< -5.00
< 20.00
* 0,50
1.00
< :5.00
< 0.20
3.00
2,00
0,18,
4;20
8.00
0.20
< 1.00
0,80
< 4,00
* 2,00
10.00
10.00
MIN
DETECTS
(M9/L)
0.2J3
0,60
0,05'
1..00
0,05
0,10
0,05
3.00
0.60
0.18'
4.20,
6.00
04O
0.80
0.05
0,06,
MEDIAN
DETECTS
(M9/L)
0.20
0.86
10:00
5.00
04J
0.10
042
3.00
.^,00
0,18
4.-80
7.00
0:20
Of8Q
0.30
0.25
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The highlighted States are part of the URCIS 24 State Cross-Section.
-------
Occurrence of 7998 CCL Priority Contaminants in Public Water Systems
Table A.1.C URCIS (Round 1) Data- Hexachlorobutadiene Occurrence in Public Water Systems- Based on Number of Systems
STATE
AK
AL
AR
AZ
CA
CO
DC
DE
EL
SA
HI
IA
IL
IN
KY
LA
MA
KID
Ml
WIN
MO
MS
MT
NC
NE
NH
NJ
NM
NV
NY
OH
SD
TN
TX
UT
VI
VT
WA
WV
Wf
TOTAL
24 ST-ATIS
TOTAL #
SAMPLES
1/45
35.1
1,104
2,008
9
48
53
130
,4.231
728
1,899
,^,07f
22
1,150
2|«54
323
644
,4,830
1,Si5
148
2,095
,-15,851
444
,4,220
2
,4,233
10
3.S8?
188
^13
45,549
TOTAL
UNIQUE
PWS
885
131
t,46
5B5
6
1
10
,'112
127
2,13
,,357
524
13
^S83
1,558
85
2§7
/«
58,0
8
356
2,855
335,
303
2
41.4
3
^§92
57
1*5
12,768
J2.284
# GW PWS
640
93
4Q7
571
3
0
8
J
,'1'12
148
321
SSI
9
838
1,529
71
,^54
,780
555
7
252
2.4B3
,-308
158,
2
381
0
837
,2S
118
11,332
10,880
# SW PWS
1-30
42
47
2,1
4
1
2
,-1 05,
,48
84
37
233
4
50
18
14
44
,44
35
2
123
188,
29
,-«7
0
34
3
,7?
31
38
1,538
1jf385
% PWS
>MRL
1.50%
3,05%
0.88%
0,00%
0.00%
0.00%
0.00%
5,36%
q«QO%
0.47%
0,00%
,,-11,00%
0.00%
0.10*4
0.00%
0.00%
0,00%
0,75%
0,00%
0.00%
0.28%
0.1.4,%
0.30%
0,3,3%
100.00%
,,-1,22%
0.00%
0.10%
0,00%
0.00%
0.36%
q.35%
% GW PWS
>MRL
1,48%
(r3Q%
0.74%
0,00%
0.00%
0.00%
0.00%
0,00%
0,00%
0,87%
0.00%
0,00?.,
0.00%
O.JW,
0,00%'
0.00%
0.00%
0,78%
0,00%
0.00%
0.40%
0)2%
0,33%
,,-0,84%
100.00%
1 .02%
0.00%
0,,11,%
0,00%,
0,00%
0.32%
0.30%,
% SW PWS
>MRL
1.54%
0,00%
2,1334
0,00%
0.00%
0.00%
0.00%
5,71%
0,00%
0,00%
0,00*4
,,-0,00%
0.00%
0,00%
0.00%
0.00%
0,00%
0,00%
0.00%
0.00%
0.00%
q«QO%
0.00%
0,00%
0.00%
2,34%
0.00%
q.OQ*4
0,00%
0.00%
0.65%
0,72%
% PWS
> 1/2 HRL
0.00%
3.05%
0.87%
0,00%
0.00%
0.00%
0.00%
5,38%
(3.00%
0,00%
0.00%,
0,00%
0.00%
0.00%
o.,oo%
0.00%
0,00%
0,25%,
0,00%
0.00%
0.28%
044,%
0,00%
,,-Q,.33%
100.00%
5,00%
0.00%
Q.,10%,
0,00%
0,00%'
0.18%
0,18%
% GW PWS
> 1/2 HRL
0.00%
(.30%
0.49%
0,00%
0.00%
0.00%
0.00%
q«,OQ%
q«QO%
q«oo%
0,00*4
,-0,00%
0.00%
q.OQ*4
0.00%
0.00%
0,00%
q.25%
0,00%
0.00%
0.40%
0.12%
0,00%
0,84%
100.00%
q«QO%
0.00%
0.11%
0,00%
0.00%
0.14%
q.t2%
% SW PWS
> 1/2 HRL
q.oo%
0,00%
2,1334
0,00%
0.00%
0.00%
0.00%
5,7,1%
q,oo%
0,00%
0.00%
0,00%
0.00%
0.00%
0,00%
0.00%
0.00%
q,oo%
q,oq%
0.00%
0.00%
0,00%
0,00**
,,-0,00%
0.00%
q,oo%
0.00%
0.00%
0,00%
0,00**
0.46%
0.51,%,
% PWS
>HRL
0.00%
1,53%
0.22%
0,00%
0.00%
0.00%
0.00%
5,38%
0,00%
q«,OQ%
0,00*4
,,-0,00%
0.00%
0,00*4
0.00%
0.00%
0,00%
0,25%
0,00%
0.00%
0.28%
q.Q8%
0.00%
13,33%
100.00%
0,00%
0.00%
q.OQ*4
0,00%
0.00%
0.12%
0.11*4
% GW PWS
>HRL
0.00%
1,15%
0.00%
0,00%
0.00%
0.00%
0.00%
0,00%
0,00%
q,QQ%
0.00%,
q,oo%
0.00%
0.00%
0,0094
0.00%
0,00%
0,25%,
0,00%
0.00%
0.40%
q,Q8%
q,op%
,,-0,84%
100.00%
q«oo%
0.00%
0.00%,
q,oo%
Q.OQ94-
0.07%
q,08%
% SW PWS
>HRL
0.00%
0.00%
2^1334
0,00%
0.00%
0.00%
0.00%
5.71%
q«QO%
q«qq%
q,oo%
,-0,00%
0.00%
q.OQ*4
q.00%
0.00%
0,00%
q«oo%
0.00%
0.00%
0.00%
0,00%
0.00%
Q,,OQ%
0.00%
q«QO%
0.00%
0,00%
fj.qq%
q.OQ%
0.46%
q.53%
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Hexachlorobutadiene is q.9 Mg/L. This is a draft value for working review only.
The highlighted States are part of the URCIS 24 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table A.2.a URCIS (Round 1) Data- Napthalene Occurrence in Public Water Systems
STATE
m
AL
AR
AZ
CA
CO
DC
DE
5-
GA
HI
IA
IL
JM
m
LA
MA
,MQ
Ml
MN
MO
MS
MT
NC
NE
NH
NJ
NP
NV
NY
QM
SO
TN
TX
UT
VI
VT
WA
JAJV
m
TOTAL
24 STATES
TOTAL
UNIQUE
PWS
689-
131
448
/em
7
1
10
114
1,181
127
.214
357
524
13
2
983
/U553-
85
2
,,-29?
9
1
783-
59Q:
8
261
2,851
335
303
3
409
3
992
5?
145
13,857
13,452
#GW
PWS
543
93'
,407
,-'592
3
0
8
8
1,052
112'
150
321
291
9
1
936
1,529
71
2
254
9
1
772
7
187
2,489
306
156
2
389.
0
937
26
,-116
12,334
1-2,034
# SW PWS
131
42
47
27
5
1
2
106
109
1:8
84
37
^233
4
1
50
28
14
0
44
0
0
n
35
2
85
188;
29
147
1
,,-34
3
,,-77
31
38
1,620
1,502
% PWS
>MRL
,4^8%:
,^28.24%
1,12%
1.15%
14.29%
0.00%
0.00%
7.02%
0,00%
/tj,00%
%i7%
0,28%:
1,15%'
0.00%
100.00%
0.51%:
0,06%
0.00%
100.00%
Q;34%
100.00%
100.00%
1,03%
0,00%
12.50%
0.38%
0.68%'
2,39%-
/Q.99f6
100.00%
1,98%'
0.00%
0,20%'
Q,00%
3.45%
1 .29%
1,18%
%GW
PWS
>MRL
5,52%
32.28%
0.98%
1,«P
0.00%
0.00%
0.00%
0,00%
,-9,QO*
0,00%
2,00%
,,-o,,,3Wo
J.Q3%
0.00%
100.00%
0,53%
0,07%
0.00%
100.00%
0.39%
100.00%
100.00%
1,04%
O.OOfo
14.29%
0.00%
0,8836
2,29%
0.64%
100.00%
1*80%
0.00%
0,21%
G,QO%
2.59%
1.18%
1.08%
%sw
PWS
>MRL
1.53%,
1«.67%
,-2.13%
,0,00%
20.00%
0.00%
0.00%
7.55%
0,00%
0,00%
%SB%
O.OOfo
1.29%
0.00%
100.00%
O.OOfo
Q.QOfo
0.00%
0.00%
Q,OQfo
0.00%
0.00%
0,00%
,'0,QOfo
0.00%
1.18%
0,80%
3.45%
1.38%
100.00%
294%;
0.00%
O.OOfo
0,00%
5.26%
2.04%
J.93%
% PWS
>HRL
0,00%'
1-S?6
0,00%
0,00%
0.00%
0.00%
0.00%
0,00%
0,00%
/0,QO%
/Q.OQ%
0.00%
,/0-9Q%
0.00%
0.00%
0,0016
0,00%
0.00%
0.00%
0,00%,
0.00%
0.00%
0,90%
O.OOfo
0.00%
0.00%
0,90%
0.00%
/u,oo%
0.00%
0,90%
0.00%
0,00%
Q,9Q%
0.00%
0.01%
0,01%
%GW
PWS
>HRL
0,00%
2.1-6%
0,00%
QW«
0.00%
0.00%
0.00%
0,00%,
0.00%
0,00%
,0,00%
0.00%
0,00%
0.00%
0.00%
0,00%
0,00%
0.00%
0.00%
0,00%
0.00%
0.00%
0,00%
,'0,00%
0.00%
0.00%
0,00%
,'0,00%
0,00%
0.00%
0,00%
0.00%
0,00%
0,00%
,'0,00%
0.02%
0,02%
%sw
PWS
>HRL
0,00%
,--Q,OOfo
0,00%
0,00%
0.00%
0.00%
0.00%
0,00%
,-Q,oo%
0,00%
0,00%
,-9,«QQ%
0,00%
0.00%
0.00%
O.OOfo
0,00%
0.00%
0.00%
0,00%
0.00%
0.00%
0,90%
0.00%
0.00%
0.00%
0,90fo
0.00%
0,00%
0.00%
0,90%
0.00%
0,00%
0,9054
0.00%
0.00%
0,00%
99%
VALUE
(M9/L)
O.§0
8.20
< 5,00
<, 10,00
4.62
< 0.50
< 0.60
8,00
5 0.60
< QS30
i, 2.00
5 2.00
< 1,09
< 0.50
0.80
5 '0.50
< ,0.50
< 50.00
14.80
< ;0.59
10.60
0.97
< 2,09
< 1,00
< 0.20
< 5.00
< 2,09
0,18
* 0,50
18.00
< 10,09
< 1.00
5 0.50
< 4,00
0,«Q
< 5.00
< 4,90
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type);
MRL= Minimum Reporting Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work as
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Naphthalene is 140 |jg/L. This is a draft value for working review only.
The highlighted States are part of the URCIS 24 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table A.2.b URCIS (Round 1) Data- Napthalene Occurrence in Public Water Systems- Based on Number of Samples
STATE
AK
AL
AR
AZ
CA
CO
DC
DE
FL
OA
HI
IA
IL
IN
m
LA
MA
,MD
Ml
MN
MO
MS
MT
NMRL
2,10*
12.1531.
0.73m
Q;l»m
9.09%
0.00%
0.00%
8,2Qm
0,00%
0,00%
0.55%
0,05%
0.48%
0.00%
100.00%
0.29%
0,04%
0.00%
100.00%
0.16%
100.00%
100.00%
o.som
0,00%
0.68%
0.07%
0.12%
1,80%
0,25%
100.00%
0,97%
0.00%
o.ism
0.00%
1.92;%
0.49%
Q.431*
%GW
SAMPLES
>MRL
2.34%
14,17%
0.43,%
Q.83%-
0.00%
0.00%
0.00%
0,00%
0,00*
0,00%
0,621,-
0,07%
0.27%
0.00%
100.00%
o.38m
0.04%
0.00%
100.00%
0.18%
100.00%
100.00%
0,56%
q,oom
0.74%
0.00%
0.12%
,-1 .93%
0,23,%-
100.00%
0:98%,
0.00%
0,14m
0,00%
,1.18%
0.00%
0,00%
%sw
SAMPLES
>MRL
0,74%
7,48%
2.44%
0,00%
16.67%
0.00%
0.00%
6,84%
o.oom
,,-0,00%
0.41%
Q.OOJI
,-Q,73%
0.00%
100.00%
o.oom
Q.oorn
0.00%
0.00%
Q.oom
0.00%
0.00%
0.00%
G.oom
0.00%
0.27%
0:.11%
1,23%
0,25%
100.00%
0.92%
0.00%
o.oom
,-0,00%
5,S|%
0.63%
0.60%
MIN
VALUE
(Mg/L)
f 0,00-
,,x 050
,,« 0.05
f 0,00
< 0.00
< 0.50
< 0.30
f 0,00
,,x 050
? 0.00
f 0,02
,,X Q.1Q,
f Q,5fl-
< 0.50
0.50
,x 0.20,
,,« 0.50,
< 0.20
0.50
,,« 0.50,
0.40
0.97
f 0,00
,,< Q,QQ
< 0.20
< 0.04
f 0,00
,,« 0.15
f 0.06-
1.80
f 0.10
< 1.00
,,X 0.50,
•? Q.5Q-
,,< 0.10
< 0.00
? Q,OQ-
99%
VALUE
(Mg/L)
Q.8Q,
8.20
< .5.00
•? 10.00
4.62
< 0.50
< 0.60
JS.QO.
< .0,50
f 0,30
•? 2.00,
< -2.00
< -1.00
< 0.50
0.80
< -0,50
< -0,50
< 50.00
14.80
< -0,50
10.60
0.97
f 2.00,
< 1.00
< 0.20
< 5.00
f 2.00,
Q,!8
f 0,50
18.00
f -10.00,
< 1.00
< -0,50
f 4,00
0,80
< 5.00
* 5.00
MAX
VALUE
(M9/L)
13.-10
906.00
10.00
25.00
4.62
< 0.50
< 0.60
10.00
f 0.50
< 0.30
13-.00
2,00
17;00
< 0.50
0.80
7,00
,"1,70
< 50.00
14.80
2.25
10.60
0.97
1,50
f -5.00
0.40
0.60
19;00
0.45
3.80
18.00
6.00
< 1.00
3.10
< 4.00
,,'2,80
906.00
906.00
MIN
DETECTS
(M9/L)
0.28
,,-0,50
0,05
0.60
4.62
1.00
0.05
2.00
1.00
0.50
0,60
,,'1-P
0.50
2.25
0.40
0.97
0.03
0.40
0.60
0,50
,,-0,15
0;70
1.80
0,50
xl^o
0,30
0.03
0.03-
MEDIAN
DETECTS
(M9/L)
0,80
,,-1,-Qq
ASQ
1.65
4.62
1,06
1,06
,2,06
2,06
0.65
1,40
1.7Q
1.30
2,25
0.90
0.97
1,06
0.40
0.60
1,06
0.20
1,00
3.90
0,50
1.8Q
0.9Q
1.00
1,00
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (
The highlighted States are part of the URCIS 24 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table A.2.C URCIS (Round 1) Data- Napthalene Occurrence in Public Water Systems- Based on Number of Systems
STATE
m
PL
AR
AZ
CA
CO
DC
DE
FL
GA
HI
IA
IL
IN
KY
LA
MA
MD
Ml
MN
MO
MS
MT
NO
NE
NH
N4
NM
NV
NY
OH
•so
TN
TX
UT
VI
VT
WA
mi
Wf
TOTAL
24 STATES
TOTAL #
SAMPLES
1,212
224
,/8ss
1,20,1
10
1
18
122
2,213
239
384
878
815
22
3
1,919
3,082
156
4
551
18
2
1,555
1,145
15
448
5,140
841
459
5
798
3
1,929
83
281
26,191
25,486
TOTAL
UNIQUE
PWS
889
13-1
448
809
7
1
10
114
1,181
12?
214
357
524
13
2
183
1,553
85
2
297
9
1
783
590
8
261
2,851
335
303
3
409
3
992
57
145
13,857
13,452
#GW
PWS
543
93
407
592
3
0
8
,8
AQ52
112
/ISO
321
291
9
1
938
A529
71
2
254
9
1
772
/ess
7
187
2,489
306
158
2
389
0
937
26
/I-18
12,334
12,034
# SW PWS
131
42
47
27
5
1
2
,406
109
18
84
37
233
4
1
50
28
14
0
44
0
0
/H
35
2
85
,488
29
/I47
1
34
3
77
3,1
38
1,620
1,502
% PWS
>MRL
4.78%
28,24%
1,12%
1,15%
14.29%
0.00%
0.00%
7.02%
0.00%
0.00%
w?%
0.28%
1,15%
0.00%
100.00%
0,51%
0.06%
0.00%
100.00%
0,34%
100.00%
100.00%
1,02%
0.00%
12.50%
0.38%
0.88%
2,39%
049%
100.00%
1,88%
0.00%
0,20%
0,00%
3.45%
1 .29%
1,1-8%
%GW
PWS
>MRL
5.52%
32.26%
OJS%
1.18%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
2.00%
0.31%
1.03%
0.00%
100.00%
0,53%
0.07%
0.00%
100.00%
0,39%
100.00%
100.00%
,4,04%
0.00%
14.29%
0.00%
0,68%
2.29%
0.84%
100.00%
,A«Q%
0.00%
0,21%
0.00%
2,59%
1.18%
1.08%
%sw
PWS
>MRL
-1.53%
,18.87%
2,13%
0.00%
20.00%
0.00%
0.00%
7.55%
0,00%
0,00%
,4.58%
0.00%
1,29%
0.00%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
1.18%
0.60%
3.45%
1,38%
100.00%
2,94%
0.00%
0.00%
0.00%
5.28%
2.04%
. 1,93%
% PWS
> 1/2 HRL
0.00%
1.53%
0.00%
0,00%
0.00%
0.00%
0.00%
0.00%
0,00%
0,00%
Q.OQ%
Q,OQ%
0,00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0.00%
0,00%
0,00%
0.00%
0.00%
0.00%
0.00%
0,00%
0,00%
0.01%
0.01%
%GW
PWS
> 1/2 HRL
0.00%
2,13%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.02%
0.02%
%sw
PWS
> 1/2 HRL
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
0.00%
1.53%
0.00%
0,00%
0.00%
0.00%
0.00%
0.00%
0,00%
0,00%
0.00%
0,00%
0,00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0.00%
0.00%
0,00%
0.00%
0.01%
0.01%
%GW
PWS
>HRL
0.00%
2,15%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0,00%
0.00%
0.02%
0.02%
%sw
PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for I;
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Naphthalene is 140 pg/L. This is a draft value for working review only.
The highlighted States are part of the URCIS 24 State Cross-Section.
-------
Appendk B. SDWIS/FED (Round 2) Data Summary for 6 CCL Contaminants
Table B. 1 .a. 1 UCM (1993) Data - Sulfate Occurrence in Public Water Systems
(HRL = 500,000 • g/L)
Table B. 1 .a.2 UCM (1993) Data - Sulfate Occurrence in Public Water Systems
(HRL = 1,000,000 • g/L)
Table B. l.b UCM (1993) Data - Sulfate Occurrence in Public Water Systems -
Based on Number of Samples
Table B.I.e. 1 UCM (1993) Data - Sulfate Occurrence in Public Water Systems -
Based on Number of Systems (HRL = 500,000 • g/L)
Table B. 1 .c.2 UCM (1993) Data - Sulfate Occurrence in Public Water Systems -
Based on Number of Systems (HRL = 1,000,000 • g/L)
Table B.2.a UCM (1993) Data - Aldrin Occurrence in Public Water Systems
Table B.2.b UCM (1993) Data - Aldrin Occurrence in Public Water Systems -
Based on Number of Samples
Table B.2.c UCM (1993) Data - Aldrin Occurrence in Public Water Systems -
Based on Number of Systems
Table B.3.a UCM (1993) Data - Dieldrin Occurrence in Public Water Systems
Table B.3.b UCM (1993) Data - Dieldrin Occurrence in Public Water Systems -
Based on Number of Samples
Table B.3.c UCM (1993) Data - Dieldrin Occurrence in Public Water Systems -
Based on Number of Systems
Table B.4.a UCM (1993) Data - Metribuzin Occurrence in Public Water Systems
Table B.4.b UCM (1993) Data - Metribuzin Occurrence in Public Water Systems -
Based on Number of Samples
Table B.4.c UCM (1993) Data - Metribuzin Occurrence in Public Water Systems -
Based on Number of Systems
Table B.5.a UCM (1993) Data - Hexachlorobutadiene Occurrence in Public Water Systems
Table B.5.b UCM (1993) Data - Hexachlorobutadiene Occurrence in Public Water Systems
Based on Number of Samples
Table B.5.c UCM (1993) Data - Hexachlorobutadiene Occurrence in Public Water Systems
Based on Number of Systems
Table B.6.a UCM (1993) Data - Naphthalene Occurrence in Public Water Systems
Table B.6.b UCM (1993) Data - Naphthalene Occurrence in Public Water Systems -
Based on Number of Samples
Table B.6.c UCM (1993) Data - Naphthalene Occurrence in Public Water Systems -
Based on Number of Systems
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.1 .a.1 SDWIS/FED (Round 2) Data- Sulfate Occurrence in Public Water Systems (HRL = 500,000 uglL)
STATE
Tribes (06)
AK
AL
V
AZ
CA
GO
CT
IN
KY
LA
MA
MD
ME
Ml
BIN
MO
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
m
sc
SD
TN
TX
VT
WA
Wl
TOTAL
10 STATES
TOTAL
UNIQUE PWS
7
238
48-1
83
48
89
,/592
,3,088
/1, 401
1..244
1,121
,-811
848
,8,88
2.J00
148
927
569
75
4,479
64
J1»
19,579
18,498
8GWPWS
7
181
380.
42
22
54
,838
2,982
A ,373
,4,141
1,116
498
,,'818
268
,-1,833
608
668
537
29
3,943
44
,/02
17,633
,18,009
8SWPWS
0
57
301-
41
,/24
,4*
,*4
/toe
3,0
./1 03
5
13
,,-29
12
,489
,,-243
259
32
46
,,-838
20
81
1,946
1,48.8
% PWS
>MRL
100.00%
90.34%
,^18,6:7%"
96.39%
100,00%
100,00%
93,41%
94.05%,
,^84.94%,
,,-91 .98%
78.77%
4,50%
99.22,%
94,40%
,,-94>fl%
89.22,%
95.25%
0.00%
92.00%
93.44%
92.19%
,,13,37%
85.45%
88.11%
% GW PWS
>MRL
100.00%
92.27%
,^85,79%
95.24%
,400,00%
100,00%
92,78%
93;94%
/84,88*)
91/24%
78.94%
4,82%
9949.%
,-9*83%
94.41%
7W%
94.91%
0.00%
89.66%
92.77%
95.45%
,/%,ei%
84.89%
87,78%
% SW PWS
>MRL
0.00%
84.21%
,99;81 %
97.56%
100.00%-
,4,00,00%
,400,00%
97,,HRL
0.00%
0.00%
1.20%
2,17%;
0,00%
0,00%
,/l,64%
,4*7%
048%
0.09%
1,87%
,,-0.00%
4,10%
6,24%
1,42%,
0.43%
0.00%
0.00%
1,*1 «
0.00%
0,00%
1.54%
1.79%
% GW PWS
>HRL
0.00%
0.00%
0,00%-
2.38%
0,,00%'
0,00%-
0,00%;
,/1,59%:
3,88%
0.09%
0.09%
1.811'
0,00%-
4>30%'
6,64%
1,18%-!
0.30%
0.00%
0.00%
1,09%-
0.00%
0,,00%'
1.58%
1,83%'
% SW PWS
>HRL
0.00%
,--'
0.00%
0,00%,
,.--"
0.00%
44,7%
0,00%,
0,00%-
,-0,00%
0,00%
0.97%,
0.00%
0,00%
0,00%
0,,00%
1.78SI
2.08%
0.77%
0.00%
0.00%
2,08%
0.00%
0,,00%
1.18%
1.4W
99% VALUE
(M9/L)
190,000
75,000
88,600
94,000
220,000
88,900
140,000
609,000
/70,000
206,000
55,700
709^00
89,000
,^68,000
20,000
388,000
203,000
5
86,000
488,000
35,900
,43,000
510,000
860,000
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for
laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Sulfate is 500,000 ug/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
Sulfate data were analyzed using two different HRLs and are, therefore, listed separately.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.1 .a. 2. SDWIS/FED (Round 2) Data- Sulfate Occurrence in Public Water Systems (HRL = 1,000,000 MS
STATE
Tribes (06)
*K
AL
W
AZ
CA
GO
CT
IN
KY
LA
MA
MD
ME
Ml
MN
MO
MS
NG
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TX
VT
WA
Wl
TOTAL
P STATES
TOTAL
UNIQUE PWS
7
238
481
83
46
86
,,682
3,858
/1 .401
1,f244
1,121
S1-1
845
/288
2,108,
848
927
569
75
4.478
64
.753
19,579
16,495
# GW PWS
7
181
380
42
y«2
64
,/538
,'2,i52
1,371
1,141
1,116
498
em
256
1,931
685
668
537
29
3,843
44
,/Q2
17,633
15,089
# SW PWS
0
57
101
41
24
15
54
/toe
,30
103
5
13
,,-29
12
18S
243,
259
32
46
536
20
61
1,946
1,486
% PWS
>MRL
100.00%
90.34%
jsBgm
96.39%
188,00%
,,4,88,08%
93,41%
94.85*
,^84,84%
,,-81.96%
78.77%
4.5,0%
98,22%
84.40%
,,,-84,81%
,,-68,22%
95.25%
0.00%
92.00%
,,-83,4/1%
92.19%
,/3.1,7%
85.45%
,-88,11%
% GW PWS
>MRL
100.00%
/
92.27%
P;?8%'
/
95.24%
,480,88%'
100,88%-
8275%
84.88%:
i-1,«4%
78.94%
98..1 9%-
84.53%'
84.41?f
71,87%
94.91%
0.00%
89.66%
82.77%;
95.45%
,/2,6)»/«'
84.89%
87.78%-
% SW PWS
>MRL
0.00%
84.21%
,,-88;O1 »A
97.56%
,488,08%
108,00%
108.88%
37.17%
88.87%:
108.88%-
40.00%
0,,88%'
188.88%,
,-81 .,67%
88.41%',
84,8/1%
96.14%
0.00%
93.48%
88,32*
85.00%
,^B'2,35%
90.49%
91,86%
% PWS
>HRL
0.00%
0.00%
1.20%
ya.17»
8,80%
8,88%
e,ae%
8,67%
8,80%
0.09%
0,80%
8,80%
,4.4f,%
1,87%
8,47%
0.00%
0.00%
0.00%
e.3s%
0.00%
0,80%
0.34%
e.,39%
% GW PWS
>HRL
0.00%
0.00%
,,0-»%
2.38%
0,00%
0,08%
0,08%
0,88%
,,-0,59%
0.08%
0.09%
0,88%
,,-0,08%
1,68%,
1,78%
Q.,33%
0.00%
0.00%
0.00%
0,23%
0.00%
0,00%
0.33%
Q.,38!»
/L)
% SW PWS
>HRL
0.00%
/
0.00%
0,80%
/
0.00%
4,17*'
0,80%
0,88%
,,-0,00%'
0,88%
0,80%
0.00%
0,00%'
0,88%
0,00%'
0,58%
0,82%
0.00%
0.00%
0.00%
0,75%
0.00%
0,00%'
0.41%
0,54%
99% VALUE
(M9/L)
190,000
75,000
88,680
94,000
220,000
85,880
140,080
508,000
,770,080
206,080
55,700
,708iOOO
88,080
,#858,000
20,080
388,080
203,000
5
86,000
488,080
35,900
,43,000
510,000
680,080
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for
laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Sulfate is 1,000,000 ug/L This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
Sulfate data were analyzed using two different HRLs and are, therefore, listed separately.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.1.b SDWIS/FED (Round 2) Data-Sulfate Occurrence in Public Water Systems- Based on Number of Samples
STATE
Tribes (06)
AK
AL
AR
AZ
CA
e©
CT
IN
KY
LA
MA
MD
ME
Ml
MN
MO
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
"K
VT
WA
Wl
TOTAL
20 STATES
TOTAL
UNIQUE PWS
7
238
481
83
48
69
§82
3,058
1,40-1
,-1,244
1,121
f-11
64S
268
2,100
848
927
569
75
4,479
64
?53
19,579
18,495
TOTAL #
SAMPLES
7
396
992
818
223
,'120
780
1,7,105
2,f30
2,391
3,139
581
68?
558
3,154
1,786
1,583
1,189
253
7,642
118
,-1,967
47,987
,40,484
#GW
SAMPLES
7
268
869
252
113
81
65t
16,310
,/2,383
2,052
3,108
564
644
536
2,820
1 ,32f
1,055
1,080
57
5.8QO
75
1,896
41 ,550
35,848
#SW
SAMPLES
0
128
329
566
110
39
,-132
J8S5
47
339
31
,-17
41
22
334
458
528
109
196
1<842
43
271
6,437
4<836
% TOTAL
SAMPLES
>MRL
100.00%
88.89%
/66,58%
92.79%
/87.44%
100.00%
,92.68%
90,01%
,/82,Sf*
90,84%
62.15%
4t82%
99.12%
93,3?%
95 J 2%
81 .48,%
95.20%
0.00%
77.47%
92.41%
77.12%
65.84%
83.52%
88,99%
%GW
SAMPLES
>MRL
100.00%
89.93%
81.00,%
98.41%
80,53%
10Q,G§»
92,§5%
89.91%
82,29,%
89,52%
62.48%
4.96%
99,07%
13,68%
94.88%
84,31%
94.31 %
0.00%
77.19%
90,97%
78.67%
87.92%
82.88%
88.68,%
%SW
SAMPLES
>MRL
0.00%
86.72%
97.87%
90.28%
94,55%
ioo.qo%
93,18%
91,81%
95,74%
98.82%
29.03%
Q,o<3«
100,00,,%
86,38%:
98,80%
53,28%,
96.97%
0.00%
77.55%
96.96%
74.42%
52,^7%
87.67%
,,-89,25%
MIN VALUE
(M9/L)
10,800
< 0
,,,« 0
< 0
,,X ,22
1
f 200
? 0
,,-< o.
f 5,000
< 3
? 0
f 1,,000
? 2,000
,,< 100
f 0
< 0
< 0
< 0
,,< 1,000
< 100
,,x 0
< 0
* 0
99% VALUE
(M9/L)
190,000
75,000
88,800.
94,000
220,000'
65,900
J 40,000
509,000
770,000
,205,000
55,700
709,000
69,000
858,,000
20,000
386,000
203,000
< 5
86,000
486.0QO.
35,900
13,000
510,000
580,000
MAX VALUE
(M9/L)
190,000
330,400
161,900
1,130,000
1,J 00,000
240,000
340,000
995,000
/1, 500,000
583,000
5,074,000
929,000
355,000
2,437,000
5,454,000
2,178,000
836,000
< 5
170,000
2,040,000
74,600
98,600
5,454,000
5,454,000
MIN
DETECTS
(M9/L)
10,800
282
1,200,
1
51
1
2,000.
3,000
/S.000
ft010
3
,'1,000
,-1,000
2,000
335
12,300
10
1,000
1,000
2,360
100-
1
1
MEDIAN
DETECTS
(M9/L)
39,700
8,595
9,300
14,000
13,100
16,150
1-0,000
31 ,000
27,000
20,100
8,200
1*0,000
,-12,000
47..0QO
64,000
49,8fO
21,000
19,000
34,000
9,700
1,500
26,000
30,000
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.1 .c.1 SDWIS/FED (Round 2) Data- Sulfate Occurrence in Public Water Systems- Based on Number of Systems (HRL = 500,000 uglL)
STATE
Tribes (06)
AK
AL
m
AZ
CA
GO
CT
IN
KY
LA
MIA
MD
ME
Ml
MN
MO
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TX
VT
WA
Wl
TOTAL
20 STATES
TOTAL #
SAMPLES
7
396
,,-992
818
223
1,20
^80
17.185
2,430
,/Sr391
3,139
591
,,-518
558
3,164
,4,188
1,583
1,189
253
/,8£Z
118
1,987
47,987
,40,414
TOTAL
UNIQUE PWS
7
238
481
83
48
89
,592
3,0-58
/I, 401
1,f244
1,121
61-1
846,
/288
2,100
848,
927
569
75
4,4?9
64
JJB3
19,579
,48,495
# GW PWS
7
181
380
42
y*2
64
,/S38
,-2,952
1,371
1.-141
1,116
498
814
268
1,931
605
668
537
29
3,943
44
,/02
17,633
1,6,009
# SW PWS
0
57
,-iei
41
24
18
54
/ioe
,30
103
5
13
,,-29
1,2
189
243
259
32
46
538
20
51
1,946
,,-1488
% PWS
>MRL
100.00%
90.34%
,^88,67%,
96.39%
1QQ,,GQ%
,,400,00%
93.41%
94.05%,
,j84.-94%
,,,-91.98%
78.77%
4.5,0%
99,22%
94.40%
,,-94,81 %
,,,-89,22%
95.25%
0.00%
92.00%
,,-93.44%
92.19%
,/3.17%
85.45%
,-88.11%
% GW PWS
>MRL
100.00%
92.27%
85:79%-
95.24%
,400,00%:
100,00%-
92,78%
,93,94%;
84.88%
91, -24%
78.94%
4.82%'
99.1 9%-
94.53%;
94.41%
71,07%)
94.91%
0.00%
89.66%
92."7?%-
95.45%
J2.51%'
84.89%
87.78%'
% SW PWS
>MRL
0.00%
/
84.21%
,,-•99,01 »/»
/
97.56%
,400:00%
100,00%,
100.00%-
97,17-%
98.67«4
100.00%
40.00%
0,00%
100.00%
,-9-1,87*
99,41%,
84,81%-
96.14%
0.00%
93.48%
98.32%
85.00%
,^82,35%
% PWS
> 1/2 HRL
0.00%
0.42%
0,00%
1.20%
4.35%
0,00%
0,5,1%
/3,37%
7.6?%
0.8814
0.09%
,*,1,5%
0,31%
1,0,48%
11,05%
5,19%
0.86%
0.00%
0.00%
8,1«,%
0.00%
0,00%
90.49%
4.24%
91,88.%-
4.97%
% GW PWS
> 1/2 HRL
0.00%
0.00%
0,00%
2.38%
f55%
0,00%
0.19%
3,39%
.7.73%,
0,88%
0.09%
2.21%,
,,,-0,32%
9,77%
1-1 .34%,
6,1,2%
0.45%
0.00%
0.00%
0.00%
0,00%
3.95%
4.81%
% SW PWS
> 1/2 HRL
0.00%
1.75%
0,00%
0.00%
4,17%'
0,00%
3.70%
,-2,83%'
0,00%
0.97%
0.00%
0,00%'
0,00%
,«5,OQ%'
7.89%
6.3,5%'
1.93%
0.00%
0.00%
18,98%
0.00%
0,00%'
6.83%
8,«6%-
% PWS
>HRL
0.00%
0.00%
0,00%
1.20%
2,17%
0,00%
0,00%
/1 ,84%
048%
0.09%
1<87%
0,00%
4,10%
6,24%
1,42%
0.43%
0.00%
0.00%
1*1%
0.00%
0,00%
1.54%
1.79%
% GW PWS
>HRL
0.00%
0.00%
,,,o«%-
2.38%
0,00%-'
0,00%
0,00%
/l,5f%-'
,3,88%
Q.09%-
0.09%
1,6,1 *
,,--0.00%
4.3,0%-'
5,54%
1,18%;
0.30%
0.00%
0.00%
1,09%
0.00%
0,00%-'
1.58%
1,83%
% SW PWS
>HRL
0.00%
0.00%
,,,Q.»%'
0.00%
4,17%
0,00%
0,00%
0.80%
,,--0,00%
tt-97%-
0.00%
0,00%
,,--0.00%
0,00%
1,,78%
,,•2,08%
0.77%
0.00%
0.00%
2,05"/«
0.00%
0,00%
1.18%
1,41%
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Sulfate is 500,000 ug/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
Sulfate data were analyzed using two different HRLs and are, therefore, listed separately.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.1 .c.2 SDWIS/FED (Round 2) Data- Sulfate Occurrence in Public Water Systems- Based on Number of Systems (HRL = 1,000,000 uglL)
STATE
Tribes (06)
AK
AL
m
AZ
CA
GO
CT
IN
KY
LA
MIA
MD
ME
Ml
MN
MO
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TX
VT
WA
Wl
TOTAL
20 STATES
TOTAL #
SAMPLES
7
396
,,"992
818
223
1,20
^80
17.185
2,430
,2,391
3,139
591
,,-518
558
3,164
,4,188
1,583
1,189
253
/..SfZ
118
1,987
47,987
,40,414
TOTAL
UNIQUE PWS
7
238
481
83
48
89
,592
3,0-58
/I, 401
1,f244
1,121
61-1
846,
/288
2,100
848,
927
569
75
4>4?9
64
JJB3
19,579
,48,495
# GW PWS
7
181
380
42
y*2
64
,/S38
,-2,952
1,371
1.-141
1,116
498
814
268
1,931
605
668
537
29
3,943
44
,/02
17,633
1,6,009
# SW PWS
0
57
,-iei
41
24
18
54
/ioe
,30
103
5
13
,,-29
1,2
189
243
259
32
46
538
20
51
1,946
1,488
% PWS
>MRL
100.00%
90.34%
,jaS,67S?>
96.39%
1QQ,,GQ%
,,400,00%
93.41%
94.05%,
,j84.-94%
,,,-91.98%
78.77%
4.5,0%
99,22%
94.40%
,,-94,81 %
,,,-89,22%
95.25%
0.00%
92.00%
,,-93.44%
92.19%
,/3.17%
85.45%
,-88.11%
% GW PWS
>MRL
100.00%
92.27%
85:79%-
95.24%
,400,00%:
100,00%-
92,78%
,93,94%;
84.88%
91,>*4%
78.94%
99.1 9%-
94.53%;
94.41%
71,07%)
94.91%
0.00%
89.66%
92."7?%-
95.45%
J2.51%'
84.89%
87.78%'
% SW PWS
>MRL
0.00%
/
84.21%
,,-99,0/1 »/»
/
97.56%
,,40Q;oe%
100,00%,
100.00%-
97,17-%
98.67«4
100.00%
40.00%
0,00%
100.00%
,,-9-1,87*
99,41%,
84,81%-
96.14%
0.00%
93.48%
98.32%
85.00%
,^82,35%
% PWS
> 1/2 HRL
0.00%
0.00%
0,00%
1.20%
,,8,1?%
0,00%
0,00%
1,54%
3,-57%
0.18%
0.09%
,4,87%
0,00%
4,10%
8,24%
1,42%
0.43%
0.00%
0.00%
1,21%
0.00%
0,00%
90.49%
91, 88.%'
1.54%
1,79%
% GW PWS
> 1/2 HRL
0.00%
0.00%
0,00%
2.38%
0,00%
0,00%
0,00%
/1 ,59%
,3,85%
0.09%
0.09%
1,81%,
,,,-0,00%
4.30%
5,54%
148%
0.30%
0.00%
0.00%
1,09%
0.00%
0,00%
1.58%
1,83%
% SW PWS
> 1/2 HRL
0.00%
0.00%
0,00%
0.00%
4,1?%'
0,00%
0,00%
,,-0,00%'
0,00%
0.97%
0.00%
0,00%'
0,00%
0,00%'
1 .78%
2,08%
0.77%
0.00%
0.00%
2.05%
0.00%
0,00%'
1.18%
1,41%-
% PWS
>HRL
0.00%
0.00%
0,00%
1.20%
2,17%
0,00%
0,00%
,-0,00%
0,57%
0.00%
0.09%
0,00%
0,00%
1,49%
1,87%
0,47%
0.00%
0.00%
0.00%
0,29%
0.00%
0,00%
0.34%
0,39%
% GW PWS
>HRL
0.00%
0.00%
,,,o«%-
2.38%
0,00%'
0,00%
0,00%
o,ao%-
,,--0,88%
0.00%
0.09%
o,eo%-
,,--0,00%
1,,88%-
1,78%:
0,33%'
0.00%
0.00%
0.00%
0.23%
0.00%
0,00%'
0.33%
0.3811
% SW PWS
>HRL
0.00%
0.00%
,,,Q,»%'
0.00%
4,17%
0,00%
0,00%
0,80%
,,--0,00%
0,00%'
0.00%
0,00%
,,--0.00%
0,00%
0,89%
0,82%
0.00%
0.00%
0.00%
0,-75%
0.00%
0,00%
0.41%
0,84%
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Sulfate is 1,000,000 ug/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
Sulfate data were analyzed using two different HRLs and are, therefore, listed separately.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.2.a SDWIS/FED (Round 2) Data- Aldrin Occurrence in Public Water Systems
STATE
Tribes (06)
AK
AL
AR
AZ
CA
GO
CT
IN
Kf
LA
Mft
MD
MB
Ml
WIN
MO
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TX
VT
Wft
Wl
TOTAL
20 STATES
iliffTATES:1 •
TOTAL
UNIQUE PWS
26
34
16
53ft
7m
70
36ft,
1,363
5ft
72ft
2,850
,/M64
318.
12
536
39ft
/593.
720
/1 ,028
88.
A«2
68
24
939
7
4V
401
58ft
15,123
12,221
12,185,
# GW PWS
25
34
11
431
538
35
184
1,295
29
669
2;S70.
1,234
280,
11
490,
258
580
891
882
78
999
57
15
841
2
122
349
5J 7
13,195
10,569
»640
# SW PWS
1
10
5
105
212
35
182
68
2?
67
80
xflO
98
1
46
38
33
29
147
22
/153
11
9
98
5
306
52
89'
1,928
1,652
1,826
% PWS
>MRL
0.00%
0.00%.
100.00%
0.00%.
0.00%.
0.00%
0.00%.
0.00%
1,7.88%.
0.00%
0.00%.
0.0054
0.00**
0.00%
0.00°*
0.0054
0.00**
0.14%.
0.00**
0.00**
0.00**
5.88%
0.00**
0.00%
0.00%
0.23**
0.00%
0.00**
0.21%
0.10%
0,02%
% GW PWS
>MRL
0.00%
0.00%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
17,24%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0,14%
0.00%
0.00%
0.00%
7.02%
0.00%
0.00%
0.00%
0-82%
0.00%
0.00%
0.17%
0.07%
0,02%.
% SW PWS
>MRL
0.00%
0:00**
100.00%
0:00**
0:00**
0.00%
0:00**
0.00%
18;62%
0.00**
0.00.°*
0.00**
0.00**
0.00%
0:00**
0.00**
0.00**
0:00**
0.00**
0.00**
0.00**
0.00%
0:00**
0.00%
0.00%
0:00**
0.00%
0:00**
0.52%
0.30%
0,00%
% PWS
>HRL
0.00%
0.0054
100.00%
0.0054
0.0054
0.00%
0.0054
0.00%
17.88%
0.0054
/0.0054
0.0054
0.0054
0.00%
Q<0054
0.0054
0.0054
0.1414
0.0054
0.0054
0.0054
5.88%
0(0054
0.00%
0.00%
0:23%
0.00%
0(0054
0.21%
0.10%
0,02%
% GW PWS
>HRL
0.00%
0.00**
100.00%
0.00**
0.00**
0.00%
0.00**
0.00%
17.24**
0.00**
0.00**
0.00**
0.00**
0.00%
0.00**
0.00**
0.00**
0,14**
0.00**
0.00**
0.00**
7.02%
0.00**
0.00%
0.00%
0.82%
0.00%
0.00**
0.17%
0.07%
8,02%
% SW PWS
>HRL
0.00%
0.00**
100.00%
0.00**
0.00**
0.00%
0.00**
0.00%
18.62%
0.00**
ooo.**
0.00**
0.00**
0.00%
0.00**
0.00**
0.00**
0.00**
0.00**
0.00**
0.00**
0.00%
0.00**
0.00%
0.00%
0.00**
0.00%
0.00**
0.52%
0.30%
0,00%
99% VALUE
(M9/L)
< 0.50
/: 0.00
0.68
/: 0.00
/: 0.00
< 0.00
/: 2,00
< 0.01
440
< 1,00
< 0.00
< 0.00
< 0.1,0
< 0.00
< 0.00
< 0.01
< 0.00
t 1.00
< .«o.o0
< 0.00
< 0.00
0.10
< 0.20
< 0.00
< 0.00
< 0.20
< 0.00
< 0.00
< 1.00
< 2.00
< 2.00
1. Massachusetts data not included in "19 States" summary statistics for Aldrin.
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory
analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Aldrin is 0.002 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.2.b SDWIS/FED (Round 2) Data-Aldrin Occurrence in Public Water Systems- Based on Number of Samples
STATE
Tribes (06)
AK
AL
AR
AZ
CA
GO
CT
IN
m
LA
MA
MD
ME
Ml
MN
mo
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TX
VT
WA
Wl
TOTAL
20 STATES
49 STOTES'
TOTAL
UNIQUE PWS
26
34
16
618
/SO
70
368
1,363
88
./SS
2;,S50
1,284
3JP
12
538
288
683
,720
AQ29
88
./1, 162
68
24
838
7
427
401
888
15,123
12,221
,,-12,186
TOTAL #
SAMPLES
36
83
25
3,6jo
2,228
312
1,557
3,333
184
1,396
1088
,-8,033
/\ ,853
28
,/«
,,-383
81$
4,288
,4,293
1,28
/2i.682
178
283
5,705
46
1,479
633
1,207
41,565
31,267
31,081
#GW
SAMPLES
35
65
17
1,226
1,388
112
,/63
3,152
JS
,4,166
3,7f1
A754
,416
25
884
3«
,1879
4,075
1,066
38
,/2,VH
131
122
4,710
16
189
506
1,005
33,531
24,827
24,761
#SW
SAMPLES
1
w
8
386
880
200
J804
181
108
,*40
308
/279
838
4
68
87
36
133
/227-
2$
/57J
48
Ifl
885
30
1,288
127
202
8,034
6,440
8,332
% TOTAL
SAMPLES
>MRL
0.00%
0,00%
100.00%
0,0084
Q,eo%
0.00%
0,00%
0.00%
13.04%
8,08%
0,88%
0,00%
8,88%
0.00%
0,00%
0,00*
8,88%
0,82%
0.00%
0,08%
0.00%
2.23%
0,0084
0.00%
0.00%
ao7%
0.00%
0,00%
0.13%
0.08%
0,0-1,%
%GW
SAMPLES
>MRL
0.00%
0,00«
100.00%
0,008$
0,00%-
0.00%
0,00«
0.00%
17.11%
,,0,00%
0,00%
0.00%
0,00%
0.00%
0,00%'
0,00%
0,00%;
0,02%'
aoo-%
0,00%'
0.00%
3.05%
0,008$
0.00%
0.00%
062%
0.00%
o,oo-%
0.11%
0.06%
0,01,%
%sw
SAMPLES
>MRL
0.00%
o,oo-%
100.00%
0,008$
0,00%.
0.00%
o,oo-%
0.00%
10.19%
,,,0,00%.
0,00%.
0.00%-
0,00%
0.00%
0,00%.
0,00%
0,00%.
0,00%.
0.00%-
0,00%
0,00%
0.00%
0,008$
0.00%
0.00%
aoos$
0.00%
o,oo-%
0.24%
0.17%
0.00%
MIN VALUE
(H9/L)
< 0.02
< 0.00
0.07
< 0,00
,,< 0,00,
< 0.00
< 0.01
< 0.01
< 0,08
< 0,01
,,< 0,00,
< 0,00
< 0,05
< 0.00
,,x 0,00,
< 0,00
< 0,00
,,< 0,01
< 0,00
< 0,00
J 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.20
< 0.00
< 0.00
< 0.00
< 0.00
< 0,00
99% VALUE
(M9/L)
< 0.50
< 0.00
0.68
< 0.00
< ,0.00
< 0.00
< 2,00
< 0.01
4.40
< 1 .00,
< ,0.00
< 0,00
< ,0.10
< 0.00
f .0.00
< 0.01
< ,,o.eo
< ,1;J)0
< ,30,00
* ,0.00
,,< 0.00
0.10
< 0.20
< 0.00
< 0.00
< 0.20
< 0.00
< 0.00
< 1.00
< 2.00
. < 4,00
MAX VALUE
(M9/L)
< 0.50
< 0.00
0.68
< 0,00
,,< 0,00'
< 0.00
< 2.00
< 0.01
4.40
< 80,00
,,< 0,00.
< 0,00
< o.io
< 0.00
,,x 0,00
< 0,01,
< 0,00.
0.48'
< 30,00
< 0,00
J 0.00
0.10
< 0.20
< 0.00
< 0.00
0,69
< 0.44
< 0.00
4.40
4.40
0,69
MIN
DETECTS
(M9/L)
0.07
040
0.48
0.10
0,69
0.07
0.10
0.46
MEDIAN
DETECTS
(M9/L)
0.12
0.«4
0-48.
0.10
0,69
0.18
0.84
0,68
1. Massachusetts data not included in "18 States" summary statistics for Aldrin.
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.2.C SDWIS/FED (Round 2) Data- Aldrin Occurrence in Public Water Systems- Based on Number of Systems
STATE
Tribes (06)
AK
AL
AR
AZ
CA
GO
CT
IN
Kf
LA
MA
MD
ME
Ml
WIN
MO
MS
m
NIJ
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TX
VT
WA
Wl
TOTAL
20 STATES
.H-fJATES1 •
TOTAL #
SAMPLES
36
m
25
1,6,»
2,228
312
1,657
3,333
164
,/lt395
4:089
6,033
1,053
29
742
383
814
4,288
1t2S3
A2Q
2,882
179
283
5,705
46
1,47i
633
1,207
41,565
31,267
31,083
TOTAL
UNIQUE PWS
26
34
16
538
,750
70
366
1,363
58
728
,-2,850
,A264
,,-378
12
538
S88
^593
m
AMRL
0.00%
0.00%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
17.88%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.14%
0.00%
0.00%
0.00%
5.88%
0,08%
0.00%
0.00%
0,231
0.00%
0.00%
0.21%
0.10%
0,02%.
% GW PWS
>MRL
0.00%
Q.ffl3%
100.00%
Q.ffl3%
Q.ffl3%
0.00%
Q.ffl3%
0.00%
17.24%
0.00%
Q.QQ.%
0.00%
0.00%
0.00%
Q.ffl3%
0.00%
0.00%
0.14*
0.00%
0.00%
0.00%
7.02%
0,00%
0.00%
0.00%
B.82%
0.00%
0,00%
0.17%
0.07%
0.02%
% SW PWS
>MRL
0.00%
0.00%
100.00%
0.00%
0.00%
0.00%
OsOQ%
0.00%
1.8.62%
0.00%.
,,-0.00%
0.00%
0.00%
0.00%
0:00%
0.00%
0.00%
0:00%
0.00%
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0,00%
0.00%
0,00%
% PWS
> 1/2 HRL
0.00%
0.00%.
100.00%
0.00%.
0.00%.
0.00%
0.00%.
0.00%
17.88%.
0.00%
0.00%.
0.00%
0.00%.
0.00%
0.00%.
0.00%
0.00%.
0.14%.
0.00%.
0.00%.
0.00%.
5.88%
0,00*
0.00%
0.00%
0,23%
0.00%
0.00*
0.52%
0.21%
0.30%
0,,00S
0.10%
0,02%
% GW PWS
> 1/2 HRL
0.00%
0.00%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
17,24%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0,14%
0.00%
0.00%
0.00%
7.02%
0.00%
0.00%
0.00%
0.82%
0.00%
0.00%
0.17%
0.07%
0.02%
% SW PWS
> 1/2 HRL
0.00%
0-ffl3%
100.00%
0-ffl3%
0:00%
0.00%
0-ffl3%
0.00%
18;62%
0.00%,
Q.00%
0.00%
0.00%
0.00%
0:00%
0.00%
0.00%
0:00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.52%
0.30%
o.,oo%.
% PWS
>HRL
0.00%
0.00%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
17.88%
0.00%
,,-0.00%
0.00%
0.00%
0.00%
Q.fflO%
0.00%
0.00%
0.14%
0.00%
0.00%
0.00%
5.88%
0.00%
0.00%
0.00%
0.23%
0.00%
0.00%
0.21%
0.10%
0,02%
% GW PWS
>HRL
0.00%
0.00%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
17.24%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.14%
0.00%
0.00%
0.00%
7.02%
0.00%
0.00%
0.00%
0,82%
0.00%
0.00%
0.17%
0.07%
0.02%
% SW PWS
>HRL
0.00%
0.00%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
18.62%
0.00%,
Q.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.52%
0.30%
0.00%
1. Massachusetts data not included in "19 States" summary statistics for Aldrin.
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Aldrin is 0.002 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.3.a SDWIS/FED (Round 2) Data- Dieldrin Occurrence in Public Water Systems
STATE
Tribes (06)
AK
AL
AR
AZ
CA
GO
CT
IN
Kf
LA
Mft
MD
MB
Ml
WIN
MO
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TX
VT
Wft
Wl
TOTAL
20 STATES
iliffTATES:1 •
TOTAL
UNIQUE PWS
25
18
4
538
749
70
44
1,363
55.
725;
2,850
,/M64
318.
12
52?
398
/593
718
/1 ,029
98.
A-148
67
15
939
7
4V
395
58?
14,725
11,843
11J88
# GW PWS
24
12
4
431
537
35
20,
1,295
28
888
2,570
1,234
280,
11
475
258
680,
887
883
78
995
56
8
841
2
122
343
5J5
12,968
10,357
18,329
# SW PWS
1
4
0
105
212
35
24
68
2?
67
80
xflO
98
1
47
38
33
29
148
22
/153
11
9
98
5
306
52
67
1,757
1,486
1,469
% PWS
>MRL
0.00%
0.00%.
100.00%
0.19%.
0.00%.
1.43%
0.00%.
0.00%
18.18°*
0.97%.
0.0054.
0.0054
0.00**
0.00%
0.38°*
0.00**
0.00**
0.00**
0.00**
0.00**
000**
7.46%
0.00**
0.00%
0.00%
0.23**
0.00%
0.00**
0.21%
0.18%
0,09%
% GW PWS
>MRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
17.88%
0,90%
0.00%
000%
0.00%
0.00%
042%
000%
0.00%
0.00%
000%
0.00%
000%
8.93%
0.00%
0.00%
0.00%
0-82%
0.00%
0.00%
0.18%
0.14%
0,09*.
% SW PWS
>MRL
0.00%
oao**
0.00%
0,95%
000%
2.86%
000%
0.00%
18;62%
1.75%
0.00.°*
0.00**
0.00**
0.00%
OflQ**
0.00**
0.00**
OflQ**
0.00**
0.00**
0.00**
0.00%
OflQ**
0.00%
0.00%
OflQ**
0.00%
OflQ**
0.46%
0.47%
0.14%
% PWS
>HRL
0.00%
0.0054
100.00%
0.19%
0.0054
1.43%
0.0054
0.00%
1«,»*4
0,97%
/0.0054
0.0054
0.0054
0.00%
Q-38%
Q<0054
0.0054
0(0054
0.0054
0.0054
0.0054
7.46%
0(0054
0.00%
0.00%
0:23%
0.00%
0(0054
0.21%
0.18%
0,09%
% GW PWS
>HRL
0.00%
0.00**
100.00%
0.00**
0.00**
0.00%
0.00**
0.00%
17.86%
Q.,90%
0.00**
0.00**
0.00**
0.00%
0.42%
0.00**
0.00**
0.00**
0.00**
0.00**
0.00**
8.93%
0.00**
0.00%
0.00%
OJ2%
0.00%
0.00**
0.18%
0.14%
0,09%
% SW PWS
>HRL
0.00%
0.00%
0.00%
0,95%
0.00%
2.86%
0.00%
0.00%
18.62%
1,75%
o.oo.**
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
000%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.46%
0.47%
0.14%
99% VALUE
(M9/L)
< 0.10
/: 0.00
0.10
/: 0.00
/: 0.00
< 0.00
/: 0=21
< 0.07
440
< 1,00
< 0.00
< 0.00
< a 10
< 0.00
< 0.00
< 0.01
< 0.00
t 0.20
< .'20,00
< 0.00
< 0.00
0.10
< 0.30
< 0.00
< 0.00
< 0.20
< 0.00
< 0.00
< 0.30
< 1.00
< 1,00
1. Massachusetts data not included in "19 States" summary statistics for Dieldrin.
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory
analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Dieldrin is 0.002 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.S.b SDWIS/FED (Round 2) Data- Dieldrin Occurrence in Public Water Systems- Based on Number of Samples
STATE
Tribes (06)
AK
AL
AR
AZ
CA
CO
CT
IN
KY
LA
M4
MD
ME
Ml
MN
MO
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TX
VT
WA
Wl
TOTAL
20 STATES
W-STATES^
TOTAL
UNIQUE PWS
25
If
4
536
J49
70
44
1,363
55
J26
2.85B
1,28.4
378
12
,,-622
,296
8S3
/«
,'1,029
99
1/148
67
1,8
939
7
w
395
582
14,725
11,843
M/ta
TOTAL #
SAMPLES
35
19
5
1810
2,226
326
216
3,333
181
1,332
4089
,6,986
1,063
29
J15?
399
6/14
4,«3
,-1,291
1SQ
.A6S1
175
26|
5,698
46
1,477
624
1,194
40,055
29,784
2i,6oa.
#GW
SAMPLES
34
16
5
1,225
1,365
116
f?
3,152
,J4
,4,166.
3,781
A-338
416
25
699
316
57S
4,071
/I,, 06.8
as
,/2,Q98
127
1J1
4,703
16
198
494
994
32,717
24,045
23,971
#SW
SAMPLES
1
4
0
385
/8«
210
128
181
10?
,,,-236
308
2/9
638
4
58
67
35
-icra
j-^£
225
24
,#686
48
143
995
30
1,284
130
200
7,338
5,739
6,832
% TOTAL
SAMPLES
>MRL
0.00%
0.00%
100.00%
0.08%
8.88%
0.31 %
0.00%
0.00%
13/28.%
0,88%
8.88%
0,00*
8,ee%
0.00%
0,40%
Q,QO%
0,00%
B.00%
o,oo.%
0,00%
0.00%
2.86%
0.0094
0.00%
0.00%
020*
0.00%
o.oo-%
0.13%
0.14%
0,08%
%GW
SAMPLES
>MRL
0.00%
0.00%
0.00%
0.0094
B.88%-
0.00%
0.00%
0.00%
1/67%
q,95,%
B.88%
0,OQ.%
0.80%
0.00%
8,43%-
0.00'%
8.88%
B.88%-
O.OQS4
O.BO%t
O.DQ-%
3.94%
0.0094
0.00%
0.00%
1.85,%
0.00%
0.00%
0.12%
0.12%
0,07%
%sw
SAMPLES
>MRL
0.00%
0.00%
0.00%
0.28%
B.00%
0.48%
0.00%
0.00%
10.28%
0,42%
B.00%
0.00%
0.08%
0.00%
8.88%
0.0094
0.00%
B.88°/4
0.009$
0.88%.
O.DQ-%
0.00%
0.0094
0.00%
0.00%
0,OQS4
0.00%
0.00%
0.19%
0.23%
0,04»
MIN VALUE
(M9/L)
< 0.01
< 0.00
0.01
< .0.00
< -ojaa
< 8. 88
< 0.01
< 0.07
< .0.02
< 8.B1
< -ojaa
,< .e.oo
< 8.85
< e.ee
f -B.ee,
,,< .0.00
< B.B8
< -B.,83
,< -8.00
< e.08
< e.oo
< e.ee
< -e.oo
< e.oo
< 0.00
< .0.20
< 0.00
< 0.00
< 0.00
< 0.00
,< .0.00
99% VALUE
(M9/L)
< 0.10
* 0..00
0.10
< .0.00
< -Q.OB
< e.ee
< 0.21
< 0.07
4,40
,« 1.08
< -8.8B
J . 8,00
,,* 8.-18.
< 8.00
< 0.00
f 0,01
,„« 0.08
< -8.28-
? 2fl.QB
,,* 8.88.
< e,,oe
0.10
< .0,30
< 0.00
< 0.00
< 0.20
< 0.00
* Q.&Q
< 0.30
< 1.00
? -1,00
MAX VALUE
(M9/L)
< 0.10
*
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.3.C SDWIS/FED (Round 2) Data- Dieldrin Occurrence in Public Water Systems- Based on Number of Systems
STATE
Tribes (06)
AK
AL
AR
AZ
CA
GO
CT
IN
Kf
LA
MA
MD
ME
Ml
WIN
MO
MS
m
NIJ
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TX
VT
WA
Wl
TOTAL
20 STATES
.la-fTATEs!1 •
TOTAL #
SAMPLES
35
19
5
i,e«
2;22S
326
m
3,333
Wl
,/lt392
4;089
5,,985
1,053
29
757
383
814
4s2S3
1i29j
/I20
2,661
175
254
5,698
46
1,477
624
1,<1,94
40,055
29,784
29,803
TOTAL
UNIQUE PWS
25
18
4
538
,749
70
44
1,363
55
72f
,-2,850
,A264
,,-378
12
522
S88
^693
,718
,/l,Q29
98
A148
67
15
939
1
42?
395
,-682
14,725
11,843
11,788
#GWPWS
24
12
4
4§1
637
35
20
1,295
28
668
,-2,570
A234
/?80
11
475
25S
^580
687
,J883
78
995
56
8-
841
2
]22
343
,-615
12,968
10,357
10,329
#SWPWS
1
4
0
105
212
35
14
68
27
67
80
x30
98
1
47
38
33
29
,448
22
,453
11
9
98
5
305
52
87
1,757
1,486
1,458
% PWS
>MRL
0.00%
0,00%
100.00%
0.19%
0.00%
143%
0.00%
0.00%
16.16%
0.97%
0.00%
0.00%
0.00%
0.00%
0.38%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
7.46%
0.08%
0.00%
0.00%
0.231
0.00%
0.08%
0.21%
0.18%
0.08%
% GW PWS
>MRL
0.00%
Q.ffl3%
0.00%
Q.ffl3%
Q.ffl3%
0.00%
Q.ffl3%
0.00%
17.86%
0,90%
0.00%
0.00%
0.00%
0.00%
0.42%
0.00%
0.00%
Q.ffl3%
0.00%
0.00%
0.00%
8.93%
0,00%
0.00%
0.00%
0.82%
0.00%
0,00%
0.18%
0.14%
Q.09%
% SW PWS
>MRL
0.00%
0.00%
0.00%
0.95%
0.00%
2.86%
0.00%
0.00%
16.52%
1.75%,
,,-0.00%
0.00%
0.00%
0.00%
0:00%
0.00%
0.00%
0:00%
0.00%
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0,00%
0.00%
0,00%
% PWS
> 1/2 HRL
0.00%
0.00%.
100.00%
0.19%.
0.00%.
143%
0.00%.
0.00%
1j9.1j9%.
0,97%'
0.00%.
0.00%
0.00%'
0.00%
0.38%
0.00%'
0.00%'
0.00%.
0.00%
0.00%'
0.00%'
7.46%
0.00*
0.00%
0.00%
0.23%
0.00%
0.00*
0.46%
0.21%
0.47%
0.14%
0.18%
0.09%
% GW PWS
> 1/2 HRL
0.00%
0.00%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
17.88%
0,90%
0.00%
0.00%
0.00%
0.00%
0.42%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
8.93%
0.08%
0.00%
0.00%
0.82%
0.00%
0.08%
0.18%
0.14%
0,09%,
% SW PWS
> 1/2 HRL
0.00%
0:00%
0.00%
0,95%
0:00%
2.86%
0-ffl3%
0.00%
18;62%
,/l.7f%
0.00%
0.00%
0.00%
0.00%
0:00%
0.00%
0.00%
0:00%
0.00%
0.00%
0.00%
0.00%
8.00%
0.00%
0.00%
8.00%
0.00%
8.00%
0.46%
0.47%
0.14%
% PWS
>HRL
0.00%
0.00%
100.00%
0.19%
0.00%
143%
0.00%
0.00%
16,16%
0.97%
0.00%
0.00%
0.00%
0.00%
0-38%
0.fflO%
0.00%
0.fflO%
0.00%
0.00%
0.00%
7.46%
0.00%
0.00%
0.00%
0.23%
0.00%
0.00%
0.21%
0.18%
Q.09%
% GW PWS
>HRL
0.00%
0.00%
100.00%
0.00%
0.00%
0.00%
0.00%
0.00%
1,7.86%
0,80%
0.00%
0.00%
0.00%
0.00%
0.42%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
8.93%
0.00%
0.00%
0.00%
0,82%
0.00%
0.00%
0.18%
0.14%
8,09%
% SW PWS
>HRL
0.00%
0.00%
0.00%
0,95%
0.00%
2.86%
0.00%
0.00%
16.52%
1,75%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.08%
0.00%
0.00%
0.08%
0.00%
0.08%
0.46%
0.47%
0.14%
1 Massachusetts data not included in "19 States" summary statistics for Dieldrin.
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Dieldrin is 0.002 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.4.a SDWIS/FED (Round 2) Data- Metribuzin Occurrence in Public Water Systems
STATE
Tribes (06)
AK
AL
AR
AZ
CA
CO
CT
IN
Kf
LA
MA,
MD
ME
HI
WIN
MO
MS
fie
ND
NH
NJ
NM
OH
QK
QR
PA
Rl
sc
SD
TN
TX
VT
WA
Wl
TOTAL
20 STATES
JlMWEflC
TOTAL
UNIQUE PWS
1
20
538
750
69
j,n
m
684
2,650
/W84
538
623
286
55,7
715
2JI8
107
.A 135
358
15
940
1
42ft
390
600
15,333
13,568
13,5t2
# GW PWS
1
V
43,1
538
35
20|
2t
627
2,570
/k?3f
437
587
258
524
888
2,017
82
984
231
8
842
2
121
338
530
13,311
11,862
H-833
# SW PWS
0
3
105
212
34
214
2?
67
80
30
,401
68
38
x33
29
181
,,-25
/J51
127
9
98
5
305
52
70
2,022
1,706
1,879
% PWS
>MRL
0.00%
0,00%
0,0054
0.00%'
0.00%
0,00%
J4,29%
0.00%
0=00%
000%
000%
000%
0.00%
000%
0:00%'
000%
000%
0.00%
9.50%
000%
0.00%
0.00%
0:00%'
0.00%
0,1,7%
0.28%
0.07%
001%
% GW PWS
>MRL
0.00%
Q.ffl3%
0.00%,
Q.,00%
0.00%
Q.ffl3%
1-3.7S%,
0:00%
Q.,00%
0.00%
Q.ffl3%
0.00%,
0.00%
Q«3%
Q.,00%
0.00%
Q.ffl3%
0.00%
5.63%
Q.,00%,
0.00%
0.00%
Q.,00%
0.00%
0,J8,%
0.14%
0.04%
0.01%
% SW PWS
>MRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
14,61,%
0,00%,
0.00%'
0.00%'
00054,
0-.OQ%
000%
000%
0.00%'
0.00%'
00054,
0.00%.
16.54%
0-.OQ%
0.00%
0.00%
0.00%
0.00%
0-flO%
1.24%
0.23%
0.00%'
% PWS
>HRL
0.00%
0.0054.
0430%'
(MB*'
0.00%
0.0054.
000%'
000%
Q-:OQ%
0.00%
000%.
OOQ%-
0.00%;
000%'
0)00%
000%:
000%.
0.00%
0.00%
OOQ%-
0.00%
0.00%
0)00%
0.00%
0.0054.
0.00%
0.00%
000%
% GW PWS
>HRL
0.00%
0.00%
0.00%'
0.00%
0.00%
0.00%
0.00%'
0,00%
0.00%
0,00%
0.00%
0:00%'
000%
000%
000%
0.00%
000%
000%
0.00%
0:00%'
0.00%
0.00%
000%
0.00%
0.00%
0.00%
0.00%
0.00%,
% SW PWS
>HRL
0.00%
Q.ffl3%
Q..QQ%
0.00%
0.00%
Q.ffl3%
Q..QQ%
0.00%
0.00%
0.00%
Q.ffl3%,
Q..QQ%
0.00%
Q.ffl3%
0.00%
0.00%
Q.ffl3%,
0.00%
0.00%
Q-.OQ%
0.00%
0.00%
0.00%
0.00%
Q.ffl3%
0.00%
0.00%
0.00%
99% VALUE
(M9/L)
< 0.09
y< am
/i. ,0..00
/: .0.00
< 0.00
/e. 10-flO
2,00
y< 0-flO
/: .0.00
< ,0.00
< 0,60
/; ,0..00
< .Q.02
< am
/i .0.80
< ,2;00
< 000
< 0.00
3.00
/; ,0.63
< 0.00
< 0.00
/< .0.20
< 0.00
y< am
< 2.00
< 2.00
< 2.00
1. Massachusetts data not included in "19 States" summary statistics for Metribuzin.
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory
analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Metribuzin is 91 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.4.b SDWIS/FED (Round 2) Data- Metribuzin Occurrence in Public Water Systems- Based on Number of Samples
STATE
Tribes (06)
AK
AL
At?
AZ
CA
CO
CT
IN
JKST
LA
MA
MD
me
m
MW
MO
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TI
VT
,WA
Wl
TOTAL
20 STATES
,1f- •STATES1
TOTAL
UNIQUE PWS
1
20
638
JfSB
69
418
88
884
3,850
1,284
,/538
833
/298
,/667
.738
2,178
187
./i.iss
358
15
940
7
428
390
800
15,333
13,568
,,-13,612
TOTAL #
SAMPLES
3
28
lejo
2,228
314
1,948
187
1,10-1
4,182
,8,988
1,798
JB?2
383
878.
4,288
,4,039
129
/2,638
1,488
188
5,703
46
1481
608
1,188
42,856
34,694
34,69?
#GW
SAMPLES
3
22
1,236
1,388
113
JUKI
J-8
|96
3,788
,/6,70e
,780:
804
318.
,,-841
4,094'
3,782
,4,80
,,'1,372
744
82
4,708
16
192
481
984
33,609
27,544
27,488
#SW
SAMPLES
0
4
388
883
201
1,078
1-11
/iQ8
382
/2?9
,4,818
88
87
36
184
/277
29
,/56?
744
108
995
30
1,289
127
202
9,247
7,150
,/,039
% TOTAL
SAMPLES
>MRL
0.00%
0,00%
Q«OQSt
0.80%
0.00%
0,00-%
%J8,Q2%
8.88%
0.88%
0,QQ%
8,88%
Q,ee%
0,00*
8.88%
8.88%
0,QQ%
8,88%
0.00%
5.65%
0,0084
0.00%
0.00%
0.00*
0.00%
0,09;%
0.23%
0.05%
0.00*
%GW
SAMPLES
>MRL
0.00%
0,00-%
O.OQS4
0,88%-
0.00%
0,00-%
1447%
,,-0.88%
0.88%
0.00%
0,08%
0,88%'
0.00%
0,08%;
0,88%-
0.00%
0.88%;
0.00%
4.17%
O.OQS4
0.00%
0.00%
O.OQ.M
0.00%
040-%
0.13%
0.04%
0.00'%
%sw
SAMPLES
>MRL
0.00%
O.QO-%
O.OQS4
0.88%.
0.00%
o«oo-%
3.6QJS
0.08%.
0.88%.
0,QQ%
0.88%.
0.88%.
0.00«*
0.08%.
0.88%.
0,QQ%
0.88%
0.00%
712%
0,OQ»
0.00%
0.00%
O.OQIA
0.00%
O.QO-%
0.62%
0.06%
0.00%
MIN VALUE
(M9/L)
< 0.09
< 0.00
< 0,00
,,< 8,88,
< 0.00
< 0.04
< 0.46
< 0.86
,,< 8,88,
< 0.00
< 0.60
,,x 8.88,
< 0.00
< 0.88
,,< 8,83
< 0.02
< 0.88
J 0.00
< 0.00
< 0,00
< 0.00
< 0.00
< 0.20
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/L)
< 0.09
t 0.00
< 0.00
< 0.80
< 0.00
* 1,0.00
2,00
,f 0.30
< 0.88
* o.oo
,,« 0.60
< -Q..80
J . 0.02
„,-* 0.00
< 0.88
* 2.00
,,* 0.00
< 0.00
3.00
< 0.53
< 0.00
< 0.00
< -0.20
< 0.00
* 0.00
< 2.00
< 2.00
* 2.00
MAX VALUE
(M9/L)
< 0.09
< 0.00
< .9.00
f ,0.80
< 0.00
< 191.0.00
2,00
< 50.00
f ,0.88
< 0.00
< 0.80
< ,0.80
< .0.02
< 0,00
f -1.80
< 4,00
< 0.00
,,< 0.00
3.00
< .0.63
< 0.00
< 0.00
< 0-20
< 0.44
om
3.00
2.00
0,10
MIN
DETECTS
(M9/L)
1,10
0.10
OdO
0.10
0.10
0.10
MEDIAN
DETECTS
(M9/L)
1.1.0
1.00
040
1.00
1.10
0,10
1. Massachusetts data not included in "19 States" summary statistics for Metribuzin.
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.4.C SDWIS/FED (Round 2) Data- Metribuzin Occurrence in Public Water Systems- Based on Number of Systems
STATE
Tribes (06)
AK
AL
AR
AZ
CA
CO
CT
IN
Kf
LA
MA
MO
ME
Ml
WIN
MQ
MS
NC
ND
NH
NJ
NM
OH
OK
OR
PA
Rl
SC
SD
TN
TR
VT
WA
Wl
TOTAL
20 STATES
18 STATES
TOTAL #
SAMPLES
3
26
1,610
2,228
314
1,845
W
,/l,1-0'1
4,1.82
5,885
1,788
,#872
4«P
576
4.28S
4,038
/1 28
,^,,128
1,488
188
5,703
46
1,481
608
1.166
42,856
34,684
34,507
TOTAL
UNIQUE PWS
1
20
538
750
68
4«
58
684
2,650
/(<264
,/5»
823
288
,Ml
715
2,1m
/ID?.
,A«8.
358
15
840
1
426
380
880
15,333
13,568
13,512
#GWPWS
1
1?
431
538!
35
204
28
62?
2,670
,/li234
437
587
25fl,
,/524
886
2,017
82
884
231
6
842
2
121
338
530
13,311
11,862
11,833
#SWPWS
0
3
105
212
34
214
27
57
80
30
101
58
38
33
28
18,1
25
tf1
127
8
88
5
305
52
70
2,022
1,706
1.878
% PWS
>MRL
0.00%
0.00%
Q.QQ%
Q.QQ%
0.00%
Q.flO%
14,28%
Q.QQff,
,,'0.00%
Q.QQff,
Q.QQff,
Q.fflQff,
Q.QQff,
Q.QQff,
Q.fflQff,
Q.QQff,
Q.QQff,
Q.QQff,
8.50%
0,00%
0.00%
0.00%
0,00%
0.00%
Q/17%
0.28%
0.07%
Q,P«
% GW PWS
>MRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
13.78%
0.00%
0.00%
O.QOff,
Q.QQff,
0.00%
O.QOff,
Q.QQff,
0.00%
O.QOff,
Q.QQff,
Q.QQff,
5.63%
0.00%
0.00%
0.00%
0.00%
0.00%
0/ISS
0.14%
0.04%
0.01%
% SW PWS
>MRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%.
14,61%.
Q.QQ%
Q.00%.
Q.QQ%
Q.QQ%
0.00%
Q.QQ%
Q.QQ%
0.00%
Q.OQ%
Q.QQ%
Q.QQ%
16.54%
Q.QB%
0.00%
0.00%
Q.QB%
0.00%
Q.OB%
% PWS
> 1/2 HRL
0.00%
Q.ffl}%
Q.ffl}%
Q.ffl3%
0.00%
Q.ffl3%
Q.ffl3%
0.00%,
,,-0.00%
0.00%.
0.00%
Q.ffl3%
000%,
0.00%
Q.ffl}%
0.00%.
0.00%
0.00%
0.00%
Q,«»
0.00%
0.00%
Q,«»
0.00%
Q.WA
1.24%| 0.00%
0.23%
Q.OO'A
0.00%
D.,00-%
% GW PWS
> 1/2 HRL
0.00%
O.QQ%
O.QQ%
O.QQ%
0.00%
O.QQ%
0:00%
0.00%
,,-0.00%
0.00%
0.00%
0:00%
0.00%
0.00%
0:00%
0.00%
0.00%
0.00%
0.00%
Q.00%
0.00%
0.00%
Q.00%
0.00%
Q.00%
0.00%
0.00%
0,00%
% SW PWS
> 1/2 HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
G.QQ%
0.00%
Q.QQ%
0.00%
0.00%
Q.QQ%
0.00%
0.00%
Q.QQ%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
0.00%
O.QQ%
O.QQ%
O.QQ%
0.00%
O.QQ%
O.QQ%
Q.QQ%
0.00%
Q.QQ%
Q.QQ%
Q.OQ%
Q.QQ%
Q.QQ%
Q.OQ%
Q.QQ%
Q.QQ%
Q.QQ%
0.00%
Q.OW
0.00%
0.00%
Q.OW
0.00%
Q.QM
0.00%
0.00%
Q.00-%.
% GW PWS
>HRL
0.00%
Q.ffl3%
Q.ffl3%
0;OO%
0.00%
Q.ffl3%
Q.ffl3%
0.00%
000%
0.00%
Q.QQ%
0;OQ%
0.00%
Q.QQ%
0;OQ%
0.00%
Q.QQ%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0,00«
% SW PWS
>HRL
0.00%
O.QQ%
O.QQ%
O.QQ%
0.00%
O.QQ%
O.QQ%
Q,OQ%
,,'0.00,%
O.QQ%
Q.OQ%
Q.fflQ%
O.QQ%
Q.OQ%
Q.fflQ%
O.QQ%
Q.OQ%
O.QQ%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
o.,oe%
1. Massachusetts data not included in "18 States" summary statistics for Metribuzin.
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Metribuzin is 81 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.S.a SDWIS/FED (Round 2) Data- Hexachlorobutadiene Occurrence in Public Water Systems
STATE
Tribes (06)
AK
AL
AR
AZ
CA
CO
CT
IN
m
LA
HA
MD
ME
HI
WIN
HO
MS
m
HO
NH
NJ
NH
GH
GK
OR
PA
Rl
SC
SD
TN
TX
VT
VW
Wl
TOTAL
20 STATES
INSTATES
TOTAL
UNIQUE PWS
22
825
40?
68
14
/831
84
117
121
1,310
41ft
878
744
2,739
,/k558
A*I2
1
1,775.
295
7
720
2,232
790
17
116
237
27
4,412
1
2,548
191
24,815
22,736
22,I3fi
# GW PWS
21
481
3^9
60
11
619
43
107
50,
1,241
344
940.
676
2,647
1,f28
1,297
1
1,595
258
7
593
2,050.
541
1«
103
216
19
3,825
0
2,429
188
22,294
20,380
28,310
# SW PWS
1
144
88
8
3
21-2
41
10
71
69
74
66
88
,82
30
/1 15
0
190
,,-38
0
2?
182
,'249
2
12
21
8
587
1
119'
3
2,521
2,356
2,356'
% PWS
>MRL
0.00%
3,38**
0.00%.
0.00%
0.00%
0,24%.
0.00%
0.00%
0.00%.
0.00%
0,24%.
0,20%.
0.00**
000**
000**
007%.
100.00%
05J%.
000**
0.00%
014%.
004%.
000**
000**
0.00**
0.00%
0.00%
0.07**
0.00%
0.00**
0.00%
0.17%
0.18%
01«%
% GW PWS
>MRL
0.00%
2.70%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
01-1%
000%
000%
000%
008**
100.00%
044%
000%
0.00%
0,14%
005%
000%
000%
0.00%
0.00%
0.00%
0.08°*
0.00%
0.00%
0.00%
0.13%
0.13%
0,13%.
% SW PWS
>MRL
0.00%
5.56,%
0-ffl3%
0.00%
0.00%
0,94%
0.00%
0.00%
0-ffl3%
0.00%
1,35%
,/l,J»,
0.00%
0.00%
0.00%
0.00%
0.00%
1.06%
0-ffl3%
0.00%
000%
0.00%
000%
000%
0-ffl3%
0.00%
0.00%
0-ffl3%
0.00%
0-ffl3%
0.00%
0.56%
0.59%
0,5t'A
% PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
Q.fflO%
0.00%
0:24%
000%
000%
000%
000%
000%
0.00%
Q.fflO%
000%
0.00%
Q.fflO%
004%
000%
000%
Q.fflO%
0.00%
0.00%
Q.flf%
0.00%
Q.fflO%
0.00%
0.02%
0.02%
Q,,02%
% GW PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.29%
0.00%
000%
000%
000%
000%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
000%
000%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0,00*
% SW PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
000%
000%
000%
000%
000%
0.00%
0.00%
000%
0.00%
0.00%
055%
000%,
000%
0.00%
0.00%
0.00%
0.34%
0.00%
0.00%
0.00%
0.12%
0.13%
Q.13K
99% VALUE
(M9/L)
< 50.00
< 0.00
< 0,10
< 1.00
< 0.50
< 0.00
< 0.00
< 2.00
< 2.50
< 0.50
< 0.50
< 0.50
< 0.00
< 0.00
< 0.50
< ,«1.QQ
0.60
< 0.00
< 050
< 1.00
< 1.00
< 050
< 000
< 000
< 1.00
< 0.50
< 0.50
1.00
< 0.50
< 0.00
< 0.30
< 1.00
< 1.00
< 1,00
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory
analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Hexachlorobutadiene is 0.9 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.S.b SDWIS/FED (Round 2) Data- Hexachlorobutadiene Occurrence in Public Water Systems- Based on Number of Samples
STATE
Tribes (06)
AK
AL
AM
AZ
CA
c»
CT
IN
KY
LA
HA
WD
WE
Ml
MN
JWD >
MS
N6
ND
MM
NJ
NKl
C-H
OK
.OR
PA
Rl
SC
SD
TN
TX
VT
WA
Wl
TOTAL
20 STATES
19 STATES
TOTAL
UNIQUE PWS
22
f|S
49?
68
14
/|31
84
117
121
1,310
418
i.78
,,'744
2,73?
3,558
1,412
1
1MRL
0.00%
0,5935,
0.09%
0.00%
0.00%
0.98*
0.00%
0.00%
0.00%
0.00%
Q.OSJfe
0.04%'
0.00%
0.99%
0.09%
0.09%'
100.00%
0.33*
0.09%
0.00%
0.92%
0.01%
0.00%'
0.09%
0.09%
0.00%
0.00%
0.02%
0.00%
0.00%
0.00%
0.04%
0.05%
0.95%
%GW
SAMPLES
>MRL
0.00%
0.50%
0.09%'
0.00%
0.00%
0,00%'
0.00%
0.00%
0.09%
0.00%
0.0,9%'
0.02%
0.09%
0,00%'
0.09%
0.03%
100.00%
0.31%'
0.09%
0.00%
0.02%'
0.01%
0.00%
0.09%
0.09%'
0.00%
0.00%
0.92%'
0.00%
0.09%
0.00%
0.04%
0.04%
0.04%
%sw
SAMPLES
>MRL
0.00%
0.86%
0.09%
0.00%
0.00%
0.21%
0.00%
0.00%
0.09%
0.00%
0.22%
048%
0.09%
0.00%
0.09%
0.00%
0.00%
0.43%
0.09%
0.00%
0.00%
0.09%
0.00%
0.09%
0.09%
0.00%
0.00%
0.09%
0.00%
0.09%
0.00%
0.09%
0.10%
OjQ%
MIN VALUE
(ijg/L)
< 0.50
« 0,09
« 0,09
< 0.40
< 0.20
«5 0,00
< 0.00
< 0.13
« 0.49
< 0.50
« 0,09
< .0,10,
« 0,00
*• 0,00:
< 0,09
i ,0,00,
0.60
«5 0,00
« 0,09
< 0.47
«5 0.50
« 0.50
i ,0,00,
« 0,0,0
« 0,09
< 0.50
< 0.50
« 0.78
< 0.50
« 0,0,9
< 0.00
< 0.00
< 0.00
«5 0,00:
99% VALUE
(ijg/L)
< 50.00
« 0,00,
« o,.n
< 1.00
< 0.50
/« 0.09
< 0.00
< 2.00
< 2.50
< 0.50
« 0.50,
« 0,50
« 0,00
« 0.00
« q.50
« ,1.09
0.60
/« 0.09
« 9,50
< 1.00
/« -ISO
« 9,50
« 0.00
« 0,00
« 1.00
< 0.50
< 0.50
1.00
< 0.50
« 0,00,
< 0.30
< 1.00
< 1.00
« ,,1.09
MAX VALUE
(M9/L)
< 50.00
0.80
« 0,10
< 1.00
< 0.50
0.20
< 0.00
< 2.00
i 2.50
< 0.50
3,10
0,80
f 0,0,9
? 0,90
? 3.Q9
0.39
0.60
0.50
< 0.50
< 1.00
0.80
J.Q8
f 0,00
i 0,0,0
* J.Q9
< 0.50
< 0.50
J. 50
< 0.50
i 0,0,0
< 0.30
1.50
1.50
1.50
MIN
DETECTS
(M9/L)
Q,1Q
0,1,0
J.10
0,10,
0.39
0.60
0.50
0.80
j.oe
0.70
0.10
0.10
0,1,0
MEDIAN
DETECTS
(M9/L)
0,29
0,15
1,10
o«s
0,39
0.60
0,59
0,80
1.08
1.49
0.30
0.30
G»ao
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.S.c SDWIS/FED (Round 2) Data- Hexachlorobutadiene Occurrence in Public Water Systems- Based on Number of Systems
STATE
Tribes (06)
m
AL
m
AZ
CA
QQ
CT
IN
JKY
LA
,MA
MO
ME
Ml
WIN
MO
MS
we
W
NH
NJ
NM
OH
QK
OR
PA
HI
SC
SD
TN
TX
VT
WA,
Wl
TOTAL
20 STATES
•tf STATEf
TOTAL #
SAMPLES
61
3,543
1,35}
134
79
2,840
1,951
210
57-1
4,055
1,919
485?
,3,546
7,351
8;8S4
,,-3.779
1
3,337
382
1
4.265
17,78ft
4,135
20
424
425
35
18,746
1
9,681
349
100,893
93,585
83,685
TOTAL
UNIQUE PWS
22
625,
407
68
14
JS33
84
117
121
1,310
416
978
744
2,739
1,658
,4,412
1
JJJ5
296
1
,,720
2,232
,790.
17'
115
237
27
4,412
1
2,54»
191
24,815
22,736
22,73$
# GW PWS
21
481
3d 9
60
11
819
43
107
60
1,241
344
920,
8J8
2,847
1,628
1t297
1
1,68f
258
1
893
2,050
541
,4«
103
216
19
3;825
0
2,429
188
22,294
20,380
,'2*|38Q
# SW PWS
1
144
/8S
8
3
212
41
10
71
69
?4
58
88
92
/30
A*5
0
190
38
0
2,7
W2
,'249
2
12
21
8
687
1
119
3
2,521
2,356
2,358
% PWS
>MRL
0.00%
3,38%.
0.00%
0.00%
0.00%
Q:r24%
0.00%
0.00%
0*0%'
0.00%
0,24%
0;20%
0.00%.
0.00%
0.00%
0.0?%
100.00%
0,51%
0.00%
0.00%
044%
0.04%
0.0054
0.00%.
0.00%
0.00%
0.00%
0.07%
0.00%
0*0%'
0.00%
0.17%
0.18%
0.18%,
% GW PWS
>MRL
0.00%
2.70°*
0.00%'
0.00%
0.00%
0.0054
0.00%
0.00%
0,00%.'
0.00%
0.00%'
041%
0,00%.'
0,00%-
0,00%'
0,08%,
100.00%
0.44%.
0.00%'
0.00%
044%.
0,05%'
0,0054
0,00%
0,00%'
0.00%
0.00%
0,08%'
0.00%
0,00%.'
0.00%
0.13%
0.13%
0.13%
% SW PWS
>MRL
0.00%
6.58*
0:00%'
0.00%
0.00%
0,94%
0.00%
0.00%
Q 1/2 HRL
0.00%
0.32%
0.00%,
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.24%,
0.10%
0,00%
0.00%
0.00%
o.,oo%
100.00%
0.51%
0,00%,
0.00%
0.14%
0,04%
O.,00%
0.00%
0.00%,
0.00%
0.00%
o.o?.%
0.00%
0.00%
0.00%
0.08%
0.08%
0,08%
% GW PWS
> 1/2 HRL
0.00%
0.21%
o-.oo%.
0.00%
0.00%
ttOQJi
0.00%
0.00%
0.00%
0.00%
o-.oo%.
0.0054
0.00%
0.0054
0.00%.
0.0054
100.00%
0.44%
0.00%.
0.00%
044%
0.05%.
0.0054
0.00%
o-.oo%.
0.00%
0.00%
0-.08%.
0.00%
0.00%
0.00%
0.06%
0.06%
0.08%.
% SW PWS
> 1/2 HRL
0.00%
0,69.x
0,00%
0.00%
0.00%
0.0054'
0.00%
0.00%
0,00%
0.00%
J.3f%
1.79%
0,00%
0,00%
0,00%
O.OO'A
0.00%
1.05%
0,00%
0.00%
0.0054'
0,00%
O.OO'A
0,00%
0,00%
0.00%
0.00%
0,00%
0.00%
0,00%
0.00%
0.20%
0.21%
0,21,%
% PWS
>HRL
0.00%
0«OQ%,
0<00%
0.00%
0.00%
0.00%
0.00%
0.00%
0:00%,
0.00%
0|24%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.04%
0.00%
0.00%
0430%
0.00%
0.00%
0436%
0.00%
0430%,
0.00%
0.02%
0.02%
0.02%
% GW PWS
>HRL
0.00%
0,00%
0.00%
0.00%
0.00%
o.,oo%
0.00%
0.00%
0,00%
0.00%
0.29%
0.00%
0,00%
0,,QO%
0,00%
0,00%
0.00%
o.,oo%
0,00%
0.00%
o.,oo%
0,00%
0,00%
0,00%
0.00%
0.00%
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0.00%
0,00%
% SW PWS
>HRL
0.00%
o-.oo%
0.00%
0.00%
0.00%
0*054
0.00%
0.00%
o-.oo%
0.00%
0.00%
0.0054
0.00%
0.0054
0.00%
0.0054
0.00%
0*054
0.00%
0.00%
0*054
0.55%
0*054
0*0%
0.00%
0.00%
0.00%
0.34%
0.00%
0*0%
0.00%
0.12%
0.13%
o.isys
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Hexachlorobutadiene is 0.9 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.6.a SDWIS/FED (Round 2) Data- Naphthalene Occurrence in Public Water Systems
STATE
Tribes (06)
AK
AL
AR
AZ
CA
CO
CT
IN
m
LA
HA
MD
ME
HI
WIN
HO
MS
m
HO
NH
NJ
NH
GH
GK
OR
PA
Rl
SC
SD
TN
TX
VT
VW
Wl
TOTAL
20 STATES
INSTATES
TOTAL
UNIQUE PWS
22
825
2
51?
68
15
/831
84
117
212'
1,310
41ft
878
744
2,737
/k55S.
,/l,412'
1,7,?S
298
3
7
714
2,232
792
17
100
237
27
4,412'
2,554
191
25,006
22,926
22,823
# GW PWS
21
481
2
423
60
12
619
43
107
103
1,241
344
920,
676
2,645
1,§28
1,297
1,586
258
MRL
0.00%
4.48*
100.00%
0.00*
1.47%
6.67%
3.97%.
1.19%
0.85%
0.47%.
0.00%
12(3%.
0.51%
0.54%.
Q,33Jfr
0.58*
0.07%.
1,1ft*
0.00*
/i go.oo*
0.00%
0.56.*
1.39*
0.78*
0.00*
0.00*
0.00%
0.00%
0.1ft*
0.31%.
0.00%
0.73%
0.77%
0,75*
% GW PWS
>MRL
0.00%
3-69%
100.00%
0.00*
1.67%
8.33%
2.75*
2.33%
0.93%
0.00*
0.00%
0.5ft*
0.14%
0.58*
0-3|*
0.48*
0.08*
1,20*
0.00*
/( 00,00*
0.00%
0.44*
1.5}%
0.92%
0.00*
0.00*
0.00%
0.00%
0.18*
0.21%
0.00%
0.60%
0.62%
0,62*
% SW PWS
>MRL
0.00%
7.64.S
0.00%
QfOQ*
0.00%
0.00%
7.55%
0.00%
0.00%
0,92*
0.00%
4.06*
7-14*
0.00*
0.00*
8.87*
0.00*
1.06*
QfOQ*
1.00.00*
4.00*
0.00*
0.40*
0.00*
QfQQ*
0.00%
0.00%
Qf34»
2,62*
0.00%
1.87%
2.00%
1,82,%
% PWS
>HRL
0.00%
0.00*
0.00%
0.00*
0.00%
0.00%
0.00*
0.00%
0.00%
QfQQ*
0.00%
QfQQ*
0.00*
0.00*
0.00*
0.00*
0.00*
QfQQ*
0.00*
0.00*
0.00%
QfQQ*
0.00*
0.00*
0.00*
QfQQ*
0.00%
0.00%
QfQQ*
QfQQ*
0.00%
0.00%
0.00%
0,08*
% GW PWS
>HRL
0.00%
0.00*
0.00%
0.00*
0.00%
0.00%
0.00*
0.00%
0.00%
0.00*
0.00%
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00%
0.00*
0.00*
0.00*
0.00*
0.00*
0.00%
0.00%
0.00*
0.00*
0.00%
0.00%
0.00%
0,00%
% SW PWS
>HRL
0.00%
0.00*
0.00*
0.00%
0.00%
0.00*
0.00%
0.00%
0.00*
0.00%
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00*
0.00%
0.00%
0.00*
0.00*
0.00%
0.00%
0.00%
0,00*
99% VALUE
(M9/L)
< 10.00
< 0.00
1.40
< 0.00
< 1.00
1.00
0.42'
< 0.00
< 2.00
< 2.50
< 0.50
< 0.50
< 0.50
< 0.00
< 0.00
< 0.50
< .'2,00
< 0.00
< 0.50
4«.40
< 1.00
< 1.00
< 0.50
< 0.00
< 0.00
< 1.00
< 0.50
< 0.50
< 1.00
< 0.00
< 0.30
< 2.00
< 2.00
< 2.00
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory
analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Naphthalene is 140 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.6.b SDWIS/FED (Round 2) Data- Naphthalene Occurrence in Public Water Systems- Based on Number of Samples
STATE
Tribes (06)
AK
AL
AM
AZ
CA
c»
CT
IN
KY
LA
HA
WD
WE
Ml
MN
JWD >
MS
N6
ND
MM
NJ
NKl
C-H
OK
.OR
PA
Rl
SC
SD
TN
TX
VT
WA
Wl
TOTAL
20 STATES
19 STATES
TOTAL
UNIQUE PWS
22
f|S
2
517
68
15
/|31
84
117
212
1,310
f1fl
87S
,,-744
2,737
3,558
1,412
KITS
288
3
7
714
2,f32
712
17
100
237
27
4,412
2,554
191
25,006
22,926
22,823
TOTAL #
SAMPLES
61
,4547
4
2,430
130
80
2,642
1,930
210
,786
4,055
1,824
4,858
9,549
8.993
8,884
3,778
/t.337'
388
5
1
4,287
17.78J
4,747
29-
270
425
35
18,780
10,083
349
102,201
94,915
14,810
#GW
SAMPLES
59
2.8,11
4
1.88Z
110
61
,1,680
845
194
308
3,451
1,370
4,308
3J43
6,154
8,878
J3.283-
,,2,877
321
1
1
4,088
18,432
3,482
18
229
385
26
12,122
W45
345
85,626
80,139
,80,138
#sw
SAMPLES
2
|38
0
448
20
19
852
1,085
16
458
604
454
^550,
49f
,838
186
4S8
46Q
8?
4
0
,201
,A3S8
1,255'
2
50
40
9
4,83f
1,018
4
16,575
14,776
14,771
% TOTAL
SAMPLES
>MRL
0.00%
0.89%
100.00%
Q.00%
0.77%
1 .25%
1,81%-
0.05%
0.48%
0.13%
0.00%
0.27%
0,12%'
0.14%
0.18%
QJilp,
0.03%'
0.8i%
O.QO%
80,,QO%'
0.00%
0.12%
0.20,%
0.13%
0.00%
O.QD%
0.00%
0.00%
0.08%
0.14%
0.00%
0.23%
0.24%
0.23%
%GW
SAMPLES
>MRL
0.00%
O.S2%
100.00%
0.00%'
0.91%
1 .64%
,1,48%'
0.12%
0.52%
0.00%
0.00%
OJ5f,'
0.02%
0,18%
a.1,8%
0.18%
0.03%
8.73%'
Q.QO%
,100.00%
0.00%
a.10%-
0.22%
0.14%
O.OQ%;
0.00%'
0.00%
0.00%
0.0B%'
0.1,1%
0.00%
0.21%
0.21%
0.21%
%SW
SAMPLES
>MRL
0.00%
1.18%
0.00%
0.00%
0.00%
0.00%
,2.42%
0.00%
0.00%
0.22%
0.00%
0.88%
0.9,1%
0.00%
0,00%
1.08%
0.00%
0.43%
0.00%
,50,,Q0%
0.00%
0.50%
0.00%
0.08%
0.00%
0.00%
0.00%
0.00%
0.04%
0.38%
0.00%
0.34%
0.39%
0,37%
MIN VALUE
(ijg/L)
< 0.50
« 0,00
0.53
« 0,00
< 0.40
< 0.20
«5 0,00
< 0.00
< 0.10
« 0.4f
< 0.50
« 0,00
«5 ,0.30,
« 0,00.
< 0,00
< 0,00
1 .0,00
«5 0,00
« 0,00
1 .0,00
< 0.41
«5 0.5Q
« 0.50
i .0,00,
« 0,0,0
« 0,00.
< 0.50
< 0.50
« 0,10
« 0,0,0
< 0.00
< 0.00
< 0.00
«5 0,00:
99% VALUE
(ijg/L)
< 10.00
« 0,00.
1.40
« 0,00.
< 1.00
1.00
0.42
< 0.00
< 2.00
« 2.50
< 0.50
« 0.50.
« 0,50
« 0,00
« 0.00
« q,50
« 2.00
,« 0.00
« q,50
,/3.,40
< 1.00
/« ..1.QQ
« q,50
« 0.00
« 0,00
« 1.00.
< 0.50
< 0.50
« 1.00
« 0,00.
< 0.30
< 2.00
< 2.00
« . 2.00
MAX VALUE
(M9/L)
< 10.00
Jf ,0,0
1.40
« 0,1.6
5.00
1.00
/3.10
0.70
2.00
0.88
< 0.50
1.30
0,80
3,60
13,00
,«0.Q0
0.80
1.80
< ,-0.50
/9.49
< 1.00
0.80
3,99
1,02
i .-0,0.0
* 3.QQ
< 0.50
< 0.50
yflO.OO
0.70
< 0.30
90.00
90.00
io.oo
MIN
DETECTS
(M9/L)
0.21
0.53
5.00
1.00
0,07'
0.70
2.00
0.88,
0.51,
0.30.
,1.4?
1,00'
,,-0,80
0.80
0.50
0.50
0.50
0.52
0.50
0,10
0,10
0.07
0.07
QJQJ
MEDIAN
DETECTS
(M9/L)
1,10
1.00
5.00
1.00
0,44
0.70
2.00
0.88
1.00
0S5Q
2.00
2.00
0.75
0,80
0,50
0,87
0,80,
0,f1
0,80
3.10
0,10
0.76
0.74
0,73
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table B.6.C SDWIS/FED (Round 2) Data- Naphthalene Occurrence in Public Water Systems- Based on Number of Systems
STATE
Tribes (06)
m
AL
m
AZ
CA
QQ
CT
IN
JKY
LA
,MA
MO
ME
Ml
WIN
MO
MS
we
W
NH
NJ
NM
OH
QK
OR
PA
HI
SC
SD
TN
TX
VT
WA,
Wl
TOTAL
20 STATES
•tf STATEf
TOTAL #
SAMPLES
61
3,547
4
2.PO
130
80
2,842
1,930
210
769
4,055
1.824
4.858
A548
6,883
6,884
J%773
3,337
sea
5
7
4.287
17,788
4,747
20
270
425
35
18,780
104383
349
102,201
94,915
84,81,0
TOTAL
UNIQUE PWS
22
625,
2
517
68
15
JS3J
84
117
21 a
1,310
418
378
744
2,737
1,558
,4.412
3J76
288
,,,'3
7
,,734
2,232
,782
17'
100,
237
27
4,41-2
2,554,
191
25,006
22,926
22,023
# GW PWS
21
481
2
423
60
12
818
43
107
103
1,241
344
820,
878
2,845
1,528
1t287
1,,688
258
/(
7
688
2,050
541
,4«
88
216
18
3,825
2,435
188
22,441
20,525
,,'2,0,524
# SW PWS
1
144
0
84
8
3
212
41
10
108
68
74
58
68
82
/30
A*5
180
38
2
0
25
182
,,'253
2
11
21
8
687
118
3
2,565
2,401
2,388
% PWS
>MRL
0.00%
4.48%,
100.00%
0.00%
1.47%
6.67%
3.87-%,
1.18%
0.85%
047'*
0.00%
1,20%
0,61%
0.54%'
Q.fl3%
0.58%.
0=07-%
3,18%
0.00%
JOO.00%
0.00%
0,68%
139%
O.J8J4
O.OO"*
0.00%
0.00%
0.00%
0,18%.
0..33*
0.00%
0.73%
0.77%
0.7,5%
% GW PWS
>MRL
0.00%
3.53%-'
100.00%
0.00%'
1.67%
8.33%
2.75%.
2.33%
0.83%
0,00%.'
0.00%
0.58%'
0.11%
0.58*
0.34S-
0.48%'
0.0854
1,|0%.
0.00%'
1,OQ,QQ54-
0.00%
0.44%.
3.51%'
0,82%
0,00%
0.00%'
0.00%
0.00%
0.18.%'
0,21,%.'
0.00%
0.60%
0.62%
0.82%
% SW PWS
>MRL
0.00%
7.84%
0.00%
0:00%'
0.00%
0.00%
7.55%
0.00%
0.00%
0,82%
0.00%
4.05%
.7.14%
0.00%
0.00%
8,87%'
0.00%
1.05%
0.00%'
1,00.00%
0.00%
4.00%
0.00%'
0.40%
0.00%
0:00%'
0.00%
0.00%
0:94%'
2.52%
0.00%
% PWS
> 1/2 HRL
0.00%
0.00%
0.00%
0.00%,
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%,
0.00%
0.00%
0.00%
Q.08%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%,
0.00%
0.00%
0.02%,
0.00%
0.00%
1.87%
2.00%
,4.82%,
0.01%
0.01%
0,01%
% GW PWS
> 1/2 HRL
0.00%
0.00%
0.00%
0-.OQ%.
0.00%
0.00%
OflQ%
0.00%
0.00%
0.00%
0.00%
0-.OQ%.
0.00%
0.00%
0.00%
0.07%.
0.00%
OflO%
0.00%.
0.00%
0.00%
OflQ%
0.00%.
0.00%
0.00%
o-.oo%.
0.00%
0.00%
0-.03%.
0.00%
0.00%
0.01%
0.01%
o.oj,%.
% SW PWS
> 1/2 HRL
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0,005%
0.00%
0.00%
0.00%
0.00%
0,00%
0.0056
0.00%
0,00%
0,00%
0.0056
0.0056
0,00%
0.0056
0.00%
0.005%
0,00%
0.0056
0,00%
0,00%
0.00%
0.00%
0,00%
0.00%
0.00%
0.00%
0.00%
0,00%
% PWS
>HRL
0.00%
0«00%,
0.00%
0<00%
0.00%
0.00%
0.00%
0.00%
0.00%
0:00%,
0.00%
0<00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0430%
0.00%
0.00%
0430%
0430%,
0.00%
0.00%
0.00%
0.00%
% GW PWS
>HRL
0.00%
0,00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0,00%
0,00%
0,00%
0,00%
0,00%
0.00%
0,00%
0,00%
0.00%
0.00%
0,00%
0,00%
0,00%
0.00%
0.00%
0.00%
0.00%
0,00%
0.00%
0.00%
0.00%
0,00%
% SW PWS
>HRL
0.00%
o-.oo%
0.00%
0.00%
0.00%
0.00%
Q<0056
0.00%
0.00%
o-.oo%
0.00%
0.00%
0.0054
0.00%
0.0054
0.00%
0.0054
0*054
0.00%
0.0054
0.00%
0*054
0.00%
0.0054
0.00%
0.00%
0.00%
0.00%
0.00%
o-.oo%
0.00%
0.00%
0.00%
0.00%
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Naphthalene is 140 |jg/L. This is a draft value for working review only.
The highlighted States are part of the SDWIS/FED 20 State Cross-Section.
-------
Appendix C. MRS Data Summary for 2 CCL Contaminants
Table C.I.a MRS Data - Manganese Occurrence in Public Water Systems
(HRL = 0.3 mg/L)
Table C.l.b NIRS Data - Manganese Occurrence in Public Water Systems
(HRL = 0.05 mg/L)
Table C.2.a NIRS Data - Sodium Occurrence in Public Water Systems
(HRL = 30 mg/L)
Table C.2.b NIRS Data - Sodium Occurrence in Public Water Systems
(HRL = 120 mg/L)
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table C.1.a. NIRS Data - Manganese Occurrence in Public Water Systems (HRL = 0.3 mg/L)
State
AK
AL
AR
AZ
CA
CO
CT
DE
FL
GA
IA
ID
IL
IN
KS
KY
LA
MA
MD
ME
Ml
MN
MO
MS
MT
NC
ND
NE
NH
NJ
NM
NV
NY
OH
OK
OR
PA
PR
Rl
SC
SD
TN
TX
UT
VA
VT
WA
Wl
WV
WY
Total
#
Samples
8
8
9
14
60
10
23
10
56
23
28
12
46
19
6
8
26
7
6
7
25
19
21
26
11
44
19
19
10
6
7
2
57
25
12
8
36
1
1
18
8
9
74
10
30
12
52
30
8
3
989
#
Samples
>MRL
7
4
6
5
26
7
18
10
29
9
22
1
34
18
3
6
24
6
5
6
22
17
16
21
5
33
19
10
8
2
5
1
32
19
6
5
28
1
1
11
7
8
51
4
25
8
31
24
3
3
672
%
Samples
>MRL
87.50%
50.00%
66.67%
35.71 %
43.33%
70.00%
78.26%
100.00%
51 .79%
39.13%
78.57%
8.33%
73.91 %
94.74%
50.00%
75.00%
92.31%
85.71%
83.33%
85.71 %
88.00%
89.47%
76.19%
80.77%
45.45%
75.00%
100.00%
52.63%
80.00%
33.33%
71 .43%
50.00%
56.14%
76.00%
50.00%
62.50%
77.78%
100.00%
100.00%
61.11%
87.50%
88.89%
68.92%
40.00%
83.33%
66.67%
59.62%
80.00%
37.50%
100.00%
67.95%
# Detects
> 1/2 HRL
2
0
0
1
2
0
0
0
0
0
5
0
1
2
1
2
3
1
0
0
2
6
3
0
1
0
3
3
0
0
1
0
4
0
0
1
7
0
0
0
2
0
0
0
0
2
3
1
1
0
60
% Detects
> 1/2 HRL
25.00%
0.00%
0.00%
7.14%
3.33%
0.00%
0.00%
0.00%
0.00%
0.00%
17.86%
0.00%
2.17%
10.53%
16.67%
25.00%
1 1 .54%
14.29%
0.00%
0.00%
8.00%
31 .58%
14.29%
0.00%
9.09%
0.00%
15.79%
15.79%
0.00%
0.00%
14.29%
0.00%
7.02%
0.00%
0.00%
12.50%
19.44%
0.00%
0.00%
0.00%
25.00%
0.00%
0.00%
0.00%
0.00%
16.67%
5.77%
3.33%
12.50%
0.00%
6.07%
# Detects
>HRL
1
0
0
1
1
0
0
0
0
0
4
0
1
1
1
1
0
0
0
0
0
4
1
0
1
0
2
2
0
0
1
0
2
0
0
0
4
0
0
0
1
0
0
0
0
2
0
0
1
0
32
% Detects
>HRL
12.50%
0.00%
0.00%
7.14%
1 .67%
0.00%
0.00%
0.00%
0.00%
0.00%
14.29%
0.00%
2.17%
5.26%
16.67%
12.50%
0.00%
0.00%
0.00%
0.00%
0.00%
21 .05%
4.76%
0.00%
9.09%
0.00%
10.53%
10.53%
0.00%
0.00%
14.29%
0.00%
3.51 %
0.00%
0.00%
0.00%
11.11%
0.00%
0.00%
0.00%
12.50%
0.00%
0.00%
0.00%
0.00%
16.67%
0.00%
0.00%
12.50%
0.00%
3.24%
Min Value
(mg/L)
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
0.01
0.03
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
0.02
< 0.00
99% Value
(mg/L)
0.50
0.05
0.06
0.58
0.65
0.13
0.09
0.08
0.03
0.05
1.34
0.13
0.36
0.33
0.83
0.50
0.25
0.19
0.05
0.04
0.20
0.63
1.22
0.09
0.33
0.09
0.63
1.24
0.11
0.09
0.38
0.00
0.40
0.13
0.08
0.17
0.86
0.01
0.03
0.07
0.72
0.08
0.13
0.02
0.13
0.33
0.18
0.18
0.76
0.09
0.63
Max Value
(mg/L)
0.50
0.05
0.06
0.58
0.65
0.13
0.09
0.08
0.03
0.05
1.34
0.13
0.36
0.33
0.83
0.50
0.25
0.19
0.05
0.04
0.20
0.63
1.22
0.09
0.33
0.09
0.63
1.24
0.11
0.09
0.38
0.00
0.40
0.13
0.08
0.17
0.86
0.01
0.03
0.07
0.72
0.08
0.13
0.02
0.13
0.33
0.18
0.18
0.76
0.09
1.34
Min
Detects
(mg/L)
0.02
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.13
0.00
0.01
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.03
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.02
0.00
Median
Detects
(mg/L)
0.05
0.01
0.01
0.00
0.01
0.00
0.01
0.01
0.00
0.02
0.01
0.13
0.01
0.03
0.07
0.02
0.01
0.00
0.02
0.01
0.02
0.09
0.00
0.01
0.07
0.01
0.01
0.05
0.05
0.05
0.02
0.00
0.03
0.02
0.00
0.01
0.02
0.01
0.03
0.01
0.06
0.00
0.02
0.00
0.01
0.00
0.01
0.02
0.10
0.02
0.01
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum
Reporting Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Manganese is 0.3 mg/L. This is a draft value for working review only.
Manganese data were analyzed using two different HRLs and are, therefore, listed separately.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table C.1.b NIRS Data - Manganese Occurrence in Public Water Systems (HRL = 0.05 mg/L)
State
AK
AL
AR
AZ
CA
CO
CT
DE
FL
GA
IA
ID
IL
IN
KS
KY
LA
MA
MD
ME
Ml
MN
MO
MS
MT
NC
ND
NE
NH
NJ
NM
NV
NY
OH
OK
OR
PA
PR
Rl
SC
SD
TN
TX
UT
VA
VT
WA
Wl
WV
WY
Total
#
Samples
8
8
9
14
60
10
23
10
56
23
28
12
46
19
6
8
26
7
6
7
25
19
21
26
11
44
19
19
10
6
7
2
57
25
12
8
36
1
1
18
8
9
74
10
30
12
52
30
8
3
989
#
Samples
>MRL
7
4
6
5
26
7
18
10
29
9
22
1
34
18
3
6
24
6
5
6
22
17
16
21
5
33
19
10
8
2
5
1
32
19
6
5
28
1
1
11
7
8
51
4
25
8
31
24
3
3
672
%
Samples
>MRL
87.50%
50.00%
66.67%
35.71 %
43.33%
70.00%
78.26%
100.00%
51 .79%
39.13%
78.57%
8.33%
73.91 %
94.74%
50.00%
75.00%
92.31%
85.71%
83.33%
85.71 %
88.00%
89.47%
76.19%
80.77%
45.45%
75.00%
100.00%
52.63%
80.00%
33.33%
71 .43%
50.00%
56.14%
76.00%
50.00%
62.50%
77.78%
100.00%
100.00%
61.11%
87.50%
88.89%
68.92%
40.00%
83.33%
66.67%
59.62%
80.00%
37.50%
100.00%
67.95%
# Detects
> 1/2 HRL
6
1
1
1
8
1
6
3
1
3
7
1
5
11
2
3
11
1
2
1
9
15
4
5
3
7
8
5
5
1
2
0
17
8
1
2
14
0
1
3
5
1
17
0
3
2
9
9
2
1
234
% Detects
> 1/2 HRL
75.00%
12.50%
11.11%
7.14%
13.33%
10.00%
26.09%
30.00%
1 .79%
13.04%
25.00%
8.33%
10.87%
57.89%
33.33%
37.50%
42.31%
14.29%
33.33%
14.29%
36.00%
78.95%
19.05%
19.23%
27.27%
15.91%
42.11%
26.32%
50.00%
16.67%
28.57%
0.00%
29.82%
32.00%
8.33%
25.00%
38.89%
0.00%
100.00%
16.67%
62.50%
11.11%
22.97%
0.00%
10.00%
16.67%
17.31%
30.00%
25.00%
33.33%
23.66%
# Detects
>HRL
4
0
1
1
6
1
1
2
0
1
5
1
2
7
2
2
9
1
0
0
6
11
3
2
3
3
5
5
5
1
1
0
12
5
1
2
13
0
0
1
4
1
7
0
3
2
6
7
2
1
158
% Detects
>HRL
50.00%
0.00%
11.11%
7.14%
10.00%
10.00%
4.35%
20.00%
0.00%
4.35%
17.86%
8.33%
4.35%
36.84%
33.33%
25.00%
34.62%
14.29%
0.00%
0.00%
24.00%
57.89%
14.29%
7.69%
27.27%
6.82%
26.32%
26.32%
50.00%
16.67%
14.29%
0.00%
21 .05%
20.00%
8.33%
25.00%
36.11%
0.00%
0.00%
5.56%
50.00%
11.11%
9.46%
0.00%
10.00%
16.67%
11.54%
23.33%
25.00%
33.33%
15.98%
Min Value
(mg/L)
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
0.01
0.03
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
0.02
< 0.00
99% Value
(mg/L)
0.50
0.05
0.06
0.58
0.65
0.13
0.09
0.08
0.03
0.05
1.34
0.13
0.36
0.33
0.83
0.50
0.25
0.19
0.05
0.04
0.20
0.63
1.22
0.09
0.33
0.09
0.63
1.24
0.11
0.09
0.38
0.00
0.40
0.13
0.08
0.17
0.86
0.01
0.03
0.07
0.72
0.08
0.13
0.02
0.13
0.33
0.18
0.18
0.76
0.09
0.63
Max Value
(mg/L)
0.50
0.05
0.06
0.58
0.65
0.13
0.09
0.08
0.03
0.05
1.34
0.13
0.36
0.33
0.83
0.50
0.25
0.19
0.05
0.04
0.20
0.63
1.22
0.09
0.33
0.09
0.63
1.24
0.11
0.09
0.38
0.00
0.40
0.13
0.08
0.17
0.86
0.01
0.03
0.07
0.72
0.08
0.13
0.02
0.13
0.33
0.18
0.18
0.76
0.09
1.34
Min
Detects
(mg/L)
0.02
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.13
0.00
0.01
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.03
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.02
0.00
Median
Detects
(mg/L)
0.05
0.01
0.01
0.00
0.01
0.00
0.01
0.01
0.00
0.02
0.01
0.13
0.01
0.03
0.07
0.02
0.01
0.00
0.02
0.01
0.02
0.09
0.00
0.01
0.07
0.01
0.01
0.05
0.05
0.05
0.02
0.00
0.03
0.02
0.00
0.01
0.02
0.01
0.03
0.01
0.06
0.00
0.02
0.00
0.01
0.00
0.01
0.02
0.10
0.02
0.01
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum
Reporting Limit (for laboratory analyses)
The Health Reference Level (HRL) is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > HRL" indicates the proportion of systems with any analytical results exceeding the concentration value of the HRL.
The Health Reference Level (HRL) used for Manganese is 0.05 mg/L. This is a draft value for working review only.
Manganese data were analyzed using two different HRLs and are, therefore, listed separately.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table C.2.a. NIRS Data - Sodium Occurrence in Public Water Systems (Benchmark Level = 30 mg/L)
State
AK
AL
AR
AZ
CA
CO
CT
DE
FL
GA
IA
ID
IL
IN
KS
KY
LA
MA
MD
ME
Ml
MN
MO
MS
MT
NO
ND
NE
NH
NJ
NM
NV
NY
OH
OK
OR
PA
PR
Rl
SO
SD
TN
TX
UT
VA
VT
WA
Wl
VW
WY
Total
# Samples
8
8
9
14
60
10
23
10
56
23
28
12
46
19
6
8
26
7
6
7
25
19
21
26
11
44
19
19
10
6
7
2
57
25
12
8
36
1
1
18
8
9
74
10
30
12
52
30
8
3
989
# Samples
>MRL
8
8
9
14
60
10
23
10
56
23
28
12
46
19
6
8
26
7
6
7
25
19
21
26
11
44
19
19
10
6
7
2
57
25
12
8
36
1
1
18
8
9
74
10
30
12
52
30
8
3
989
% Samples
>MRL
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
# Detects
> 1/2 Benchmark
Level
1
2
6
10
48
5
5
4
16
4
13
5
36
12
4
6
23
1
4
3
11
10
9
16
8
15
18
11
3
1
6
2
32
15
8
6
22
1
1
4
7
1
64
4
9
4
13
6
3
1
519
% Detects
> 1/2 Benchmark
Level
12.50%
25.00%
66.67%
71.43%
80.00%
50.00%
21.74%
40.00%
28.57%
17.39%
46.43%
41.67%
78.26%
63.16%
66.67%
75.00%
88.46%
14.29%
66.67%
42.86%
44.00%
52.63%
42.86%
61.54%
72.73%
34.09%
94.74%
57.89%
30.00%
16.67%
85.71%
100.00%
56.14%
60.00%
66.67%
75.00%
61.11%
100.00%
100.00%
22.22%
87.50%
11.11%
86.49%
40.00%
30.00%
33.33%
25.00%
20.00%
37.50%
33.33%
52.48%
# Detects
> Benchmark
Level
1
1
6
10
34
4
0
3
8
0
11
2
26
5
4
6
21
1
3
3
9
8
5
15
6
8
18
5
0
1
5
1
14
9
8
2
13
0
1
2
5
0
58
2
6
2
7
3
2
1
365
% Detects
> Benchmark
Level
12.50%
12.50%
66.67%
71.43%
56.67%
40.00%
0.00%
30.00%
14.29%
0.00%
39.29%
16.67%
56.52%
26.32%
66.67%
75.00%
80.77%
14.29%
50.00%
42.86%
36.00%
42.11%
23.81%
57.69%
54.55%
18.18%
94.74%
26.32%
0.00%
16.67%
71.43%
50.00%
24.56%
36.00%
66.67%
25.00%
36.11%
0.00%
100.00%
11.11%
62.50%
0.00%
78.38%
20.00%
20.00%
16.67%
13.46%
10.00%
25.00%
33.33%
36.91%
Min Value
(mg/L)
2.96
1.43
9.70
12.43
2.96
2.76
4.81
4.68
1.17
1.51
4.38
3.61
3.00
4.49
7.27
3.59
2.40
3.22
5.80
2.11
2.67
3.30
1.56
1.99
2.76
1.95
2.38
4.10
3.41
1.66
10.41
28.54
1.82
3.34
9.16
7.41
1.79
27.34
68.19
3.29
11.80
2.82
4.56
3.75
1.23
0.91
2.58
1.18
1.35
7.07
0.91
99% Value
(mg/L)
82.80
150.86
249.51
284.28
292.14
224.10
22.60
109.10
90.43
26.90
174.20
90.19
516.83
194.60
185.00
137.80
495.03
52.60
121.90
55.59
462.13
270.67
178.70
187.45
808.78
259.57
906.00
133.10
25.44
51.85
174.73
81.25
1541.00
494.60
181.20
78.30
188.40
27.34
68.19
263.17
763.30
17.18
645.89
134.62
355.52
143.11
282.00
445.07
249.22
340.39
516.83
Max Value
(mg/L)
82.80
150.86
249.51
284.28
292.14
224.10
22.60
109.10
90.43
26.90
174.20
90.19
516.83
194.60
185.00
137.80
495.03
52.60
121.90
55.59
462.13
270.67
178.70
187.45
808.78
259.57
906.00
133.10
25.44
51.85
174.73
81.25
1541.00
494.60
181.20
78.30
188.40
27.34
68.19
263.17
763.30
17.18
645.89
134.62
355.52
143.11
282.00
445.07
249.22
340.39
1541.00
Min Detects
(mg/L)
2.96
1.43
9.70
12.43
2.96
2.76
4.81
4.68
1.17
1.51
4.38
3.61
3.00
4.49
7.27
3.59
2.40
3.22
5.80
2.11
2.67
3.30
1.56
1.99
2.76
1.95
2.38
4.10
3.41
1.66
10.41
28.54
1.82
3.34
9.16
7.41
1.79
27.34
68.19
3.29
11.80
2.82
4.56
3.75
1.23
0.91
2.58
1.18
1.35
7.07
0.91
Median
Detects
(mg/L)
6.04
3.65
39.50
46.56
34.01
16.92
8.88
12.92
8.84
10.08
13.89
13.47
40.78
18.80
45.75
47.01
75.30
8.49
33.74
6.90
12.54
20.05
8.98
41.03
39.28
9.51
280.21
22.10
11.83
5.63
58.95
54.89
16.63
18.64
38.76
19.30
19.87
27.34
68.19
10.66
63.73
4.83
96.05
10.58
7.34
4.98
7.78
4.94
10.30
13.99
16.35
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The Benchmark Level is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > Benchmark Level" indicates the proportion of systems with any analytical results exceeding the concentration value of the Benchmark Level.
The Benchmark Level used for Sodium is 30 mg/L. This is a draft value for working review only.
Sodium data were analyzed using two different Benchmark Levels and are, therefore, listed separately.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table C.2.b. NIRS Data - Sodium Occurrence in Public Water Systems (Benchmark Level = 120 mg/L)
State
AK
AL
AR
AZ
CA
CO
CT
DE
FL
GA
IA
ID
IL
IN
KS
KY
LA
MA
MD
ME
Ml
MN
MO
MS
MT
NC
ND
NE
NH
NJ
NM
NV
NY
OH
OK
OR
PA
PR
Rl
SC
SD
TN
TX
UT
VA
VT
WA
Wl
WV
WY
Total
# Samples
8
8
9
14
60
10
23
10
56
23
28
12
46
19
6
8
26
7
6
7
25
19
21
26
11
44
19
19
10
6
7
2
57
25
12
8
36
1
1
18
8
9
74
10
30
12
52
30
8
3
989
# Samples
>MRL
8
8
9
14
60
10
23
10
56
23
28
12
46
19
6
8
26
7
6
7
25
19
21
26
11
44
19
19
10
6
7
2
57
25
12
8
36
1
1
18
8
9
74
10
30
12
52
30
8
3
989
% Samples
>MRL
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
100.00%
# Detects
> 1/2 Benchmark
Level
1
1
4
5
12
2
0
2
2
0
8
1
18
1
2
2
18
0
1
0
9
6
3
9
4
3
15
2
0
0
3
1
5
6
3
1
6
0
1
1
4
0
46
1
6
1
3
3
1
1
224
% Detects
> 1/2 Benchmark
Level
12.50%
12.50%
44.44%
35.71%
20.00%
20.00%
0.00%
20.00%
3.57%
0.00%
28.57%
8.33%
39.13%
5.26%
33.33%
25.00%
69.23%
0.00%
16.67%
0.00%
36.00%
31.58%
14.29%
34.62%
36.36%
6.82%
78.95%
10.53%
0.00%
0.00%
42.86%
50.00%
8.77%
24.00%
25.00%
12.50%
16.67%
0.00%
100.00%
5.56%
50.00%
0.00%
62.16%
10.00%
20.00%
8.33%
5.77%
10.00%
12.50%
33.33%
22.65%
# Detects
> Benchmark
Level
0
1
3
2
4
1
0
0
0
0
4
0
10
1
2
2
8
0
1
0
1
3
2
4
4
1
14
1
0
0
1
0
2
4
2
0
5
0
0
1
3
0
33
1
3
1
2
2
1
1
131
% Detects
> Benchmark
Level
0.00%
12.50%
33.33%
14.29%
6.67%
10.00%
0.00%
0.00%
0.00%
0.00%
14.29%
0.00%
21.74%
5.26%
33.33%
25.00%
30.77%
0.00%
16.67%
0.00%
4.00%
15.79%
9.52%
15.38%
36.36%
2.27%
73.68%
5.26%
0.00%
0.00%
14.29%
0.00%
3.51%
16.00%
16.67%
0.00%
13.89%
0.00%
0.00%
5.56%
37.50%
0.00%
44.59%
10.00%
10.00%
8.33%
3.85%
6.67%
12.50%
33.33%
13.25%
Mm Value
(mg/L)
2.96
1.43
9.70
12.43
2.96
2.76
4.81
4.68
1.17
1.51
4.38
3.61
3.00
4.49
7.27
3.59
2.40
3.22
5.80
2.11
2.67
3.30
1.56
1.99
2.76
1.95
2.38
4.10
3.41
1.66
10.41
28.54
1.82
3.34
9.16
7.41
1.79
27.34
68.19
3.29
11.80
2.82
4.56
3.75
1.23
0.91
2.58
1.18
1.35
7.07
0.91
99% Value
(mg/L)
82.80
150.86
249.51
284.28
292.14
224.10
22.60
109.10
90.43
26.90
174.20
90.19
516.83
194.60
185.00
137.80
495.03
52.60
121.90
55.59
462.13
270.67
178.70
187.45
808.78
259.57
906.00
133.10
25.44
51.85
174.73
81.25
1541.00
494.60
181.20
78.30
188.40
27.34
68.19
263.17
763.30
17.18
645.89
134.62
355.52
143.11
282.00
445.07
249.22
340.39
516.83
Max Value
(mg/L)
82.80
150.86
249.51
284.28
292.14
224.10
22.60
109.10
90.43
26.90
174.20
90.19
516.83
194.60
185.00
137.80
495.03
52.60
121.90
55.59
462.13
270.67
178.70
187.45
808.78
259.57
906.00
133.10
25.44
51.85
174.73
81.25
1541.00
494.60
181.20
78.30
188.40
27.34
68.19
263.17
763.30
17.18
645.89
134.62
355.52
143.11
282.00
445.07
249.22
340.39
1541.00
Mm Detects
(mg/L)
2.96
1.43
9.70
12.43
2.96
2.76
4.81
4.68
1.17
1.51
4.38
3.61
3.00
4.49
7.27
3.59
2.40
3.22
5.80
2.11
2.67
3.30
1.56
1.99
2.76
1.95
2.38
4.10
3.41
1.66
10.41
28.54
1.82
3.34
9.16
7.41
1.79
27.34
68.19
3.29
11.80
2.82
4.56
3.75
1.23
0.91
2.58
1.18
1.35
7.07
0.91
Median
Detects
(mg/L)
6.04
3.65
39.50
46.56
34.01
16.92
8.88
12.92
8.84
10.08
13.89
13.47
40.78
18.80
45.75
47.01
75.30
8.49
33.74
6.90
12.54
20.05
8.98
41.03
39.28
9.51
280.21
22.10
11.83
5.63
58.95
54.89
16.63
18.64
38.76
19.30
19.87
27.34
68.19
10.66
63.73
4.83
96.05
10.58
7.34
4.98
7.78
4.94
10.30
13.99
16.35
PWS= Public Water Systems; GW= Ground Water (PWS Source Water Type); SW= Surface Water (PWS Source Water Type); MRL= Minimum Reporting Limit (for laboratory analyses)
The Benchmark Level is the estimated health effect level as provided by EPA for preliminary assessment for this work assignment.
"% > Benchmark Level" indicates the proportion of systems with any analytical results exceeding the concentration value of the Benchmark Level.
The Benchmark Level used for Sodium is 120 mg/L. This is a draft value for working review only.
Sodium data were analyzed using two different Benchmark Levels and are, therefore, listed separately.
-------
Appendix D. Comparison of URCIS (Round 1) Data to SDWIS/FED
(Round 2) Data for Select States and Select Contaminants
Table D. 1 .a URCIS (Round 1) and SDWIS/FED (Round 2) Data - Hexachlorobutadiene
Occurrence in Public Water Systems - Based on Number of Samples
Table D. 1 .b URCIS (Round 1) and SDWIS/FED (Round 2) Data - Hexachlorobutadiene
Occurrence in Public Water Systems - Based on Number of Systems
Table D.2.a URCIS (Round 1) and SDWIS/FED (Round 2) Data - Naphthalene Occurrence
in Public Water Systems - Based on Number of Samples
Table D.2.b URCIS (Round 1) and SDWIS/FED (Round 2) Data - Naphthalene Occurrence
in Public Water Systems - Based on Number of Systems
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table D.1 .a URCIS (Round 1) and SDWIS/FED (Round 2) Data- Hexachlorobutadiene Occurrence in Public Water Systems - Based on Number of Samples
STATE
AK- URCIS (Round 1)
AK - SDWIS/FED (Round 2)
KY- URCIS (Round 1)
KY - SDWIS/FED (Round 2)
MD- URCIS (Round 1)
MD - SDWIS/FED (Round 2)
MN- URCIS (Round 1)
MN - SDWIS/FED (Round 2)
NC- URCIS (Round 1)
NC - SDWIS/FED (Round 2)
NM -URCIS (Round 1)
NM -SDWIS/FED (Round 2)
OH- URCIS (Round 1)
OH - SDWIS/FED (Round 2)
WA- URCIS (Round 1)
WA - SDWIS/FED (Round 2)
TOTAL *
SAMPLES
1,745
3,543
2,076
571
1,750
4,857
2,654
6,864
644
3,337
1,595
4,265
15,951
17,788
3,987
9,567
*GW
SAMPLES
1,480
2,610
1,119
203
1,376
4,306
2,586
6,678
569
2,877
1,475
4,065
15,038
16,432
3,656
8,683
*SW
SAMPLES
265
933
957
368
374
551
68
186
75
460
120
200
913
1,356
331
884
% TOTAL
SAMPLES
>MRL
0.63%
0.59%
0.00%
0.00%
0.06%
0.04%
0.00%
0.00%
0.00%
0.33%
0.00%
0.02%
0.02%
0.01%
0.03%
0.00%
%GW
SAMPLES
>MRL
0.61%
0.50%
0.00%
0.00%
0.07%
0.02%
0.00%
0.00%
0.00%
0.31%
0.00%
0.02%
0.02%
0.01%
0.03%
0.00%
%sw
SAMPLES
>MRL
0.75%
0.86%
0.00%
0.00%
0.00%
0.18%
0.00%
0.00%
0.00%
0.43%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
(ug'L)
< 0.00
< 0.00
< 0.50
< 0.40
< 0.10
< 0.10
< 0.50
< 0.00
< 0.50
< 0.00
< 0.00
< 0.50
< 0.20
< 0.50
< 0.50
< 0.00
99% VALUE
(ug'L)
< 0.00
< 0.00
< 1.00
< 2.50
< 0.50
< 0.50
< 0.50
< 0.50
< 0.50
< 0.00
< 1.00
< 1.00
2.00
< 0.50
0.50
< 0.00
MAX VALUE
(ug'L)
0.30
0.80
< 1.00
< 2.50
0.10
0.60
< 5.00
< 1.00
< 0.50
0.50
< 5.00
0.80
2.00
1.06
0.60
< 0.00
MIN
DETECTS
(ug/L)
0.20
0.10
0.10
0.10
0.50
0.80
0.50
1.06
0.60
MEDIAN
DETECTS
(ug/L)
0.20
0.20
0.10
0.35
0.50
0.80
2.00
1.06
0.60
Table D.1 .b URCIS (Round 1) and SDWIS/FED (Round 2) Data- Hexachlorobutadiene Occurrence in Public Water Systems - Based on Number of Systems
STATE
AK- URCIS (Round 1)
AK - SDWIS/FED (Round 2)
KY- URCIS (Round 1)
KY - SDWIS/FED (Round 2)
MD- URCIS (Round 1)
MD - SDWIS/FED (Round 2)
MN- URCIS (Round 1)
MN - SDWIS/FED (Round 2)
NC- URCIS (Round 1)
NC - SDWIS/FED (Round 2)
NM -URCIS (Round 1)
NM -SDWIS/FED (Round 2)
OH- URCIS (Round 1)
OH - SDWIS/FED (Round 2)
WA- URCIS (Round 1)
WA - SDWIS/FED (Round 2)
TOTAL
UNIQUE PWS
670
625
524
121
986
976
1,557
1,558
298
1,775
590
720
2,659
2,232
1,014
2,548
3GWPWS
540
481
291
50
936
920
1,529
1,528
254
1,585
555
693
2,493
2,050
937
2,429
3SWPWS
130
144
233
71
50
56
28
30
44
190
35
27
166
182
77
119
% PWS
>MRL
1.49%
3.36%
0.00%
0.00%
0.10%
0.20%
0.00%
0.00%
0.00%
0.51%
0.00%
0.14%
0.11%
0.04%
0.10%
0.00%
% GW PWS
>MRL
1 .48%
2.70%
0.00%
0.00%
0.11%
0.11%
0.00%
0.00%
0.00%
0.44%
0.00%
0.14%
0.12%
0.05%
0.11%
0.00%
% SW PWS
>MRL
1.54%
5.56%
0.00%
0.00%
0.00%
1.79%
0.00%
0.00%
0.00%
1.05%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
> 1/2 HRL
0.30%
0.00%
0.00%
0.00%
0.00%
0.10%
0.00%
0.00%
0.00%
0.51%
0.00%
0.14%
0.11%
0.04%
0.10%
0.00%
% GW PWS
> 1/2 HRL
0.19%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.44%
0.00%
0.14%
0.12%
0.05%
0.11%
0.00%
% SW PWS
> 1/2 HRL
0.77%
0.00%
0.00%
0.00%
0.00%
1.79%
0.00%
0.00%
0.00%
1.05%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.08%
0.04%
0.00%
0.00%
% GW PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.08%
0.05%
0.00%
0.00%
% SW PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
The Health Reference Level (HRL) used for Hexachlorobutadiene is 0.9 (ug/L). This is a draft value for working review only.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table D.2.a URCIS (Round 1) and SDWIS/FED (Round 2) Data- Na
STATE
AK- URCIS (Round 1)
AK - SDWIS/FED (Round 2)
KY- URCIS (Round 1)
KY - SDWIS/FED (Round 2)
MD- URCIS (Round 1)
MD - SDWIS/FED (Round 2)
MN- URCIS (Round 1)
MN - SDWIS/FED (Round 2)
NC- URCIS (Round 1)
NC - SDWIS/FED (Round 2)
NM -URCIS (Round 1)
NM -SDWIS/FED (Round 2)
OH -URCIS (Round 1)
OH - SDWIS/FED (Round 2)
WA- URCIS (Round 1)
WA - SDWIS/FED (Round 2)
TOTAL *
SAMPLES
1,763
3,547
2,076
766
1,749
4,856
2,656
6,864
644
3,337
1,595
4,287
15,944
17,788
3,987
10,063
*GW
SAMPLES
1,494
2,611
1,119
308
1,375
4,306
2,588
6,678
569
2,877
1,475
4,086
15,030
16,432
3,656
9,045
*SW
SAMPLES
269
936
957
458
374
550
68
186
75
460
120
201
914
1,356
331
1,018
phthalene Occurrence in Public Water Systems - Based on Number of Samples
% TOTAL
SAMPLES
>MRL
2.10%
0.99%
0.48%
0.13%
0.29%
0.12%
0.04%
0.20%
0.16%
0.69%
0.00%
0.12%
0.12%
0.20%
0.13%
0.14%
% GW
SAMPLES
>MRL
2.34%
0.92%
0.27%
0.00%
0.36%
0.02%
0.04%
0.18%
0.18%
0.73%
0.00%
0.10%
0.12%
0.22%
0.14%
0.11%
% sw
SAMPLES
>MRL
0.74%
1.18%
0.73%
0.22%
0.00%
0.91%
0.00%
1.08%
0.00%
0.43%
0.00%
0.50%
0.11%
0.00%
0.00%
0.39%
MIN VALUE
(ug/L)
< 0.00
< 0.00
< 0.50
< 0.40
< 0.20
< 0.30
< 0.50
< 0.00
< 0.50
< 0.00
< 0.00
< 0.50
< 0.00
< 0.50
< 0.50
< 0.00
99% VALUE
(ug/L)
0.80
< 0.00
< 1.00
< 2.50
< 0.50
< 0.50
< 0.50
< 0.50
< 0.50
< 0.00
< 1.00
< 1.00
< 2.00
< 0.50
< 0.50
< 0.00
MAX VALUE
(ug/L)
13.10
18.00
17.00
0.86
7.00
0.60
1.70
90.00
2.25
1.80
< 5.00
0.80
19.00
3.90
3.10
0.70
MIN
DETECTS
(ug'L)
0.28
0.21
1.00
0.86
0.60
0.30
1.70
0.60
2.25
0.50
0.50
0.50
0.52
1.50
0.10
MEDIAN
DETECTS
(ug'L)
0.80
1.10
2.00
0.86
1.40
0.50
1.70
0.75
2.25
0.50
0.60
1.00
0.91
1.60
0.10
Table D.2.b URCIS (Round 1) and SDWIS/FED (Round 2) Data- Na
STATE
AK- URCIS (Round 1)
AK - SDWIS/FED (Round 2)
KY- URCIS (Round 1)
KY - SDWIS/FED (Round 2)
MD- URCIS (Round 1)
MD - SDWIS/FED (Round 2)
MN- URCIS (Round 1)
MN - SDWIS/FED (Round 2)
NC- URCIS (Round 1)
NC - SDWIS/FED (Round 2)
NM -URCIS (Round 1)
NM -SDWIS/FED (Round 2)
OH -URCIS (Round 1)
OH - SDWIS/FED (Round 2)
WA- URCIS (Round 1)
WA - SDWIS/FED (Round 2)
TOTAL
UNIQUE
PWS
674
625
524
212
986
976
1,557
1,558
298
1,776
590
714
2,655
2,232
1,014
2,554
* GW PWS
543
481
291
103
936
920
1,529
1,528
254
1,586
555
689
2,489
2,050
937
2,435
3SWPWS
131
144
233
109
50
56
28
30
44
190
35
25
166
182
77
119
phthalene Occurrence in Public Water Systems - Based on Number of Systems
% PWS
>MRL
4.75%
4.48%
1.15%
0.47%
0.51%
0.51%
0.06%
0.58%
0.34%
1.18%
0.00%
0.56%
0.68%
1.39%
0.20%
0.31%
% GW PWS
>MRL
5.52%
3.53%
1.03%
0.00%
0.53%
0.11%
0.07%
0.46%
0.39%
1.20%
0.00%
0.44%
0.68%
1.51%
0.21%
0.21%
% SW PWS
>MRL
1.53%
7.64%
1.29%
0.92%
0.00%
7.14%
0.00%
6.67%
0.00%
1.05%
0.00%
4.00%
0.60%
0.00%
0.00%
2.52%
% PWS
> 1/2 HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.06%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% GW PWS
> 1/2 HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.07%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS
> 1/2 HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% GW PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS
>HRL
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
The Health Reference Level (HRL) used for Naphthalene is 140 (ug/L). This is a draft value for working review only.
-------
Appendix E. Summary Data for URCIS (Round 1) and SDWIS/FED
(Round 2) for Select Contaminants by System Type and Population Served
Table E.I.a URCIS (Round 1) Data - Hexachlorobutadiene Occurrence in Community Water
Systems by Population Served
Table E.l.b. URCIS (Round 1) Data - Hexachlorobutadiene Occurrence in Non- Transient
Non- Community Water Systems by Population Served
Table E.2.a URCIS (Round 1) Data - Naphthalene Occurrence in Community Water
Systems by Population Served
Table E.2.b. URCIS (Round 1) Data - Naphthalene Occurrence in Non- Transient Non-
Community Water Systems by Population Served
Table E.3.a. 1 SDWIS/FED (Round 2) Data - Sulfate Occurrence in Community Water
Systems by Population Served (HRL = 500,000 • g/L)
Table E.3.b. 1 SDWIS/FED (Round 2) Data - Sulfate Occurrence in Non- Transient Non-
Community Water Systems by Population Served (HRL = 500,000 • g/L)
Table E.3.a.2 SDWIS/FED (Round 2) Data - Sulfate Occurrence in Community Water
Systems by Population Served (HRL = 1,000,000 • g/L)
Table E.3.b.2 SDWIS/FED (Round 2) Data - Sulfate Occurrence in Non- Transient Non-
Community Water Systems by Population Served (HRL = 1,000,000 • g/L)
Table E.4.a SDWIS/FED (Round 2) Data - Aldrin Occurrence in Community Water Systems
by Population Served
Table E.4.b. SDWIS/FED (Round 2) Data - Aldrin Occurrence in Non- Transient Non-
Community Water Systems by Population Served
Table E.5.a SDWIS/FED (Round 2) Data - Dieldrin Occurrence in Community Water
Systems by Population Served
Table E.5.b. SDWIS/FED (Round 2) Data - Dieldrin Occurrence in Non- Transient Non-
Community Water Systems by Population Served
Table E.6.a SDWIS/FED (Round 2) Data - Metribuzin Occurrence in Community Water
Systems by Population Served
Table E.6.b. SDWIS/FED (Round 2) Data - Metribuzin Occurrence in Non- Transient Non-
Community Water Systems by Population Served
Table E.7.a SDWIS/FED (Round 2) Data - Hexachlorobutadiene Occurrence in Community
Water Systems by Population Served
Table E.7.b. SDWIS/FED (Round 2) Data - Hexachlorobutadiene Occurrence in Non-
Transient Non- Community Water Systems by Population Served
Table E.S.a SDWIS/FED (Round 2) Data - Naphthalene Occurrence in Community Water
Systems by Population Served
Table E.S.b. SDWIS/FED (Round 2) Data - Naphthalene Occurrence in Non- Transient Non-
Community Water Systems by Population Served
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table E.1.a URCIS (Round 1) Data- Hexachlorobutadiene Occurrence in Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
24 1
0.22%
0.10%
0.23%
0.93%
1.46%
0.29%
ALL2
0.22%
0.20%
0.21%
0.89%
1 .40%
0.32%
% GW PWS
>MRL
24 1
0.11%
0.06%
0.17%
1.23%
2.40%
0.23%
ALL2
0.11%
0.18%
0.15%
1.17%
2.33%
0.26%
% SW PWS
>MRL
24 1
2.26%
0.33%
0.35%
2.44%
6.38%
0.61%
ALL2
2.23%
0.33%
0.34%
2.33%
5.94%
0.59%
% PWS
> 1/2 HRL
24 1
0.19%
0.10%
0.12%
0.40%
0.98%
0.21%
ALL2
0.19%
0.20%
0.11%
0.38%
0.93%
0.24%
% GW PWS
> 1/2 HRL
24 1
0.09%
0.06%
0.00%
0.61%
1.60%
0.16%
ALL2
0.09%
0.18%
0.00%
0.59%
1 .55%
0.18%
% SW PWS
> 1/2 HRL
24 1
2.26%
0.33%
0.35%
0.00%
0.00%
0.52%
ALL2
2.23%
0.33%
0.34%
0.00%
0.00%
0.51%
% PWS
>HRL
24 1
0.14%
0.05%
0.12%
0.00%
0.00%
0.16%
ALL2
0.14%
0.15%
0.11%
0.00%
0.00%
0.18%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS
>HRL
24 1
0.06%
0.06%
0.00%
0.00%
0.00%
0.09%
ALL2
0.06%
0.18%
0.00%
0.00%
0.00%
0.12%
% SW PWS
>HRL
24 1
1.69%
0.00%
0.35%
0.00%
0.00%
0.52%
ALL2
1 .68%
0.00%
0.34%
0.00%
0.00%
0.51%
MIN VALUE
ftjg/L)
24 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/L)
24 1
< 5.00
< 2.00
< 4.00
< 5.00
< 5.00
< 5.00
ALL2
< 5.00
< 2.00
< 4.00
< 5.00
< 5.00
< 5.00
MAX VALUE
ftjg/L)
24 1
10.00
5.00
10.00
1.00
1.00
10.00
ALL2
10.00
8.00
10.00
1.00
1.00
10.00
MIN DETECTS
ftjg/L)
24 1
0.16
2.00
0.20
0.10
0.05
0.05
ALL2
0.16
2.00
0.20
0.10
0.05
0.05
MEDIAN DETECTS
ftjg/L)
24 1
3.10
3.50
10.00
0.20
0.17
0.65
ALL2
3.10
5.50
10.00
0.20
0.17
0.83
Table E.1.b URCIS (Round 1) Data- Hexachlorobutadiene Occurrence in Non-Transient Non-Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
24 1
0.14%
0.40%
11.11%
0.00%
0.20%
ALL2
0.14%
0.40%
11.11%
0.00%
0.20%
% GW PWS
>MRL
24 1
0.14%
0.42%
11.11%
0.00%
0.21%
ALL2
0.14%
0.42%
11.11%
0.00%
0.21%
% SW PWS
>MRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
> 1/2 HRL
24 1
0.00%
0.20%
0.00%
0.00%
0.09%
ALL2
0.00%
0.20%
0.00%
0.00%
0.09%
% GW PWS
> 1/2 HRL
24 1
0.00%
0.21%
0.00%
0.00%
0.09%
ALL2
0.00%
0.21%
0.00%
0.00%
0.09%
% SW PWS
> 1/2 HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS > HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS > HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
ftjg/L)
24 1
< 0.00
< 0.00
< 0.05
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.05
< 0.00
< 0.00
99% VALUE
(M9/L)
24 1
< 2.00
< 2.00
0.05
< 10.00
< 2.00
ALL2
< 2.00
< 2.00
0.05
< 10.00
< 2.00
MAX VALUE
ftjg/L)
24 1
0.50
1.00
0.05
< 10.00
1.00
ALL2
0.50
1.00
0.05
< 10.00
1.00
MIN DETECTS
ftjg/L)
24 1
0.05
0.13
0.05
0.05
ALL2
0.05
0.13
0.05
0.05
MEDIAN DETECTS
ftjg/L)
24 1
0.30
0.57
0.05
0.13
ALL2
0.30
0.57
0.05
0.13
1. Analyses are based on data from the URCIS 24 State Cross-Section of: AK, AL, AZ, CA, FL, GA, HI, IA, IL, IN, KY, MD, MN, MT, NC, NJ, NM, OH, SD, TN, UT, WA, WV, WY.
2. Analyses are based on data from all 40 States in the URCIS database.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table E.2.a URCIS (Round 1) Data- Naphthalene Occurrence in Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
24 1
0.54%
0.68%
2.19%
2.63%
4.89%
1 .07%
ALL2
0.69%
0.90%
2.40%
2.56%
4.74%
1 .25%
% GW PWS
>MRL
24 1
0.41%
0.58%
2.62%
2.34%
6.15%
0.89%
ALL2
0.58%
0.79%
2.94%
2.24%
5.97%
1.08%
% SW PWS
>MRL
24 1
3.26%
1.23%
1.25%
2.89%
2.70%
2.08%
ALL2
3.23%
1.53%
1.22%
3.09%
3.36%
2.26%
% PWS
> 1/2 HRL
24 1
0.00%
0.05%
0.10%
0.00%
0.00%
0.02%
ALL2
0.00%
0.02%
0.05%
0.00%
0.00%
0.02%
% GW PWS
> 1/2 HRL
24 1
0.00%
0.05%
0.15%
0.00%
0.00%
0.03%
ALL2
0.00%
0.02%
0.05%
0.00%
0.00%
0.03%
% SW PWS
> 1/2 HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
24 1
0.00%
0.05%
0.10%
0.00%
0.00%
0.02%
ALL2
0.00%
0.02%
0.05%
0.00%
0.00%
0.02%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS
>HRL
24 1
0.00%
0.05%
0.15%
0.00%
0.00%
0.03%
ALL2
0.00%
0.02%
0.05%
0.00%
0.00%
0.03%
% SW PWS
>HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
ftjg/L)
24 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/L)
24 1
< 5.00
< 3.00
< 5.00
< 5.00
< 5.00
< 5.00
ALL2
< 5.00
< 4.00
< 5.00
< 5.00
< 5.00
< 5.00
MAX VALUE
ftjg/L)
24 1
25.00
900.00
906.00
19.00
13.00
906.00
ALL2
25.00
900.00
906.00
19.00
18.00
906.00
MIN DETECTS
ftjg/L)
24 1
0.15
0.18
0.50
0.50
0.05
0.05
ALL2
0.15
0.18
0.40
0.50
0.05
0.05
MEDIAN DETECTS
ftjg/L)
24 1
2.00
1.90
1.40
1.00
1.00
1.02
ALL2
1.30
1.75
1.50
0.96
1.00
1.02
Table E.2.b URCIS (Round 1) Data- Naphthalene Occurrence in Non-Transient Non-Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
24 1
0.75%
1.15%
10.00%
0.00%
0.84%
ALL2
0.79%
1.15%
9.09%
0.00%
0.84%
% GW PWS
>MRL
24 1
0.77%
1.22%
10.00%
0.00%
0.86%
ALL2
0.80%
1.22%
10.00%
0.00%
0.86%
% SW PWS
>MRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
> 1/2 HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% GW PWS
> 1/2 HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS
> 1/2 HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS > HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS > HRL
24 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
ftjg/L)
24 1
< 0.00
< 0.00
< 0.05
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.05
< 0.00
< 0.00
99% VALUE
(M9/L)
24 1
< 2.00
< 5.00
0.05
< 10.00
< 2.00
ALL2
< 2.00
< 5.00
0.05
< 10.00
< 2.00
MAX VALUE
ftjg/L)
24 1
14.20
7.00
0.05
< 10.00
14.20
ALL2
14.20
7.00
0.05
< 10.00
14.20
MIN DETECTS
ftjg/L)
24 1
0.03
0.70
0.05
0.03
ALL2
0.03
0.70
0.05
0.03
MEDIAN DETECTS
ftjg/L)
24 1
0.90
0.95
0.05
0.90
ALL2
0.80
0.95
0.05
0.90
1. Analyses are based on data from the URCIS 24 State Cross-Section of: AK, AL, AZ, CA, FL, GA, HI, IA, IL, IN, KY, MD, MN, MT, NC, NJ, NM, OH, SD, TN, UT, WA, WV, WY.
2. Analyses are based on data from all 40 States in the URCIS database.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table E.3.a.1 SDWIS/FED (Round 2) Data- Sulfate Occurrence in Community Water Systems by Population Served (HRL = 500,000 M9/L)
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
85.27%
90.76%
92.96%
95.71%
93.94%
88.08%
ALL2
81.46%
87.97%
90.26%
94.09%
94.89%
85.19%
% GW PWS
>MRL
20 1
85.15%
90.77%
93.60%
94.12%
94.87%
87.55%
ALL2
81.25%
87.59%
91.20%
92.82%
95.00%
84.34%
% SW PWS
>MRL
20 1
86.75%
90.71%
91.46%
97.35%
93.55%
91.61%
ALL2
85.51%
90.28%
88.21%
95.21%
94.85%
90.51%
% PWS
> 1/2 HRL
20 1
4.50%
6.19%
5.23%
8.58%
9.85%
5.30%
ALL2
4.00%
4.69%
4.02%
6.31%
7.39%
4.39%
% GW PWS
> 1/2 HRL
20 1
4.45%
5.85%
3.81%
4.41%
7.69%
4.80%
ALL2
3.96%
4.34%
2.93%
3.45%
7.50%
4.00%
% SW PWS
> 1/2 HRL
20 1
5.62%
8.08%
8.54%
12.88%
10.75%
8.83%
ALL2
5.07%
6.81%
6.39%
8.82%
7.35%
6.93%
% PWS
>HRL
20 1
1.82%
1.51%
1.17%
1.49%
0.76%
1.65%
ALL2
1.63%
1.19%
0.93%
1.21%
0.57%
1.39%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS
>HRL
20 1
1.81%
1.53%
1.07%
1.84%
2.56%
1.69%
ALL2
1.62%
1.17%
0.90%
1.44%
2.50%
1.42%
% SW PWS
>HRL
20 1
2.01%
1.41%
1.42%
1.14%
0.00%
1.37%
ALL2
1.81%
1.30%
0.98%
1.01%
0.00%
1.15%
MIN VALUE
ftjg/U
20 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
ftjg/U
20 1
672,000
470,000
360,000
408,000
346,000
488,000
ALL2
583,000
457,000
338,000
371,000
340,000
MAX VALUE
ftjg/U
20 1
2,437,000
3,880,000
1,217,000
1,619,000
635,000
457,000 3,880,000
ALL2
2,437,000
5,074,000
1,217,000
1,619,000
635,000
5,074,000
MIN DETECTS
ftjg/U
20 1
3.00
3.00
100.00
1.00
100.00
1.00
ALL2
3.00
2.80
10.40
1.00
3.40
1.00
MEDIAN DETECTS
ftjg/U
20 1
24,900
34,000
37,000
34,000
27,000
31,000
ALL2
23,000
30,000
30,700
26,000
23,000
23,000
Table E.3.b.1 SDWIS/FED (Round 2) Data- Sulfate Occurrence in Non-Transient Non-Community Water Systems by Population Served (HRL = 500,000 M9/L)
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
87.96%
89.97%
94.44%
100.00%
100.00%
88.24%
ALL2
85.72%
88.07%
95.45%
75.00%
100.00%
86.11%
% GW PWS
>MRL
20 1
87.94%
89.58%
93.75%
100.00%
100.00%
88.16%
ALL2
85.68%
87.88%
95.00%
66.67%
100.00%
86.03%
%SWPWS
>MRL
20 1
89.47%
100.00%
100.00%
100.00%
0.00%
92.31%
ALL2
88.61%
93.55%
100.00%
100.00%
0.00%
90.27%
% PWS
> 1/2 HRL
20 1
4.36%
3.44%
11.11%
0.00%
0.00%
4.26%
ALL2
4.07%
2.79%
9.09%
0.00%
0.00%
3.89%
% GW PWS
> 1/2 HRL
20 1
4.32%
3.58%
12.50%
0.00%
0.00%
4.25%
ALL2
4.04%
2.77%
10.00%
0.00%
0.00%
3.86%
% SW PWS
> 1/2 HRL
20 1
6.58%
0.00%
0.00%
0.00%
0.00%
4.81%
ALL2
6.33%
3.23%
0.00%
0.00%
0.00%
5.31%
% PWS
>HRL
20 1
2.11%
1.95%
0.00%
0.00%
0.00%
2.08%
ALL2
1.98%
1.45%
0.00%
0.00%
0.00%
1.89%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
%GWPWS>HRL
20 1
2.11%
2.02%
0.00%
0.00%
0.00%
2.09%
ALL2
1.97%
1.50%
0.00%
0.00%
0.00%
1.89%
% SW PWS > HRL
20 1
2.63%
0.00%
0.00%
0.00%
0.00%
1.92%
ALL2
2.53%
0.00%
0.00%
0.00%
0.00%
1.77%
MIN VALUE
ftjg/U
20 1
< 0.00
< 0.00
< 0.00
21,000.00
8,000.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
5.00
8,000.00
< 0.00
99% VALUE
ftjg/U
20 1
709,000
626,000
410,000
144,000
16,000
685,000
ALL2
680,000
600,000
410,000
144,000
16,000
660,000
MAX VALUE
ftjg/U
20 1
4,250,000
5,454,000
410,000
144,000
16,000
5,454,000
ALL2
4,250,000
5,454,000
410,000
144,000
16,000
5,454,000
MIN DETECTS
ftjg/U
20 1
100
200
1,200
21,000
8,000
100
ALL2
10
10
1,000
4,090
8,000
10
MEDIAN DETECTS
ftjg/U
20 1
27,000
24,000
12,000
82,500
11,000
26,000
ALL2
26,000
22,000
10,000
4,430
11,000
26,000
1. Analyses are based on data from the SDWIS/FED 20 State Cross-Section of: AK, AR, CO, KY, MA, MD, ME, Ml, MN, MO, NC, ND, NH, NM, OH, OK, OR, Rl, TX, WA.
2. Analyses are based on data from all 35 States in the SDWIS/FED database.
Sulfate data were analyzed using two different HRLs, and are, therefore, listed separately.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table E.3.a.2 SDWIS/FED (Round 2) Data- Sulfate Occurrence in Community Water Systems by Population Served (HRL = 1,000,000 M9/L)
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
85.27%
90.76%
92.96%
95.71%
93.94%
88.08%
ALL2
81.46%
87.97%
90.26%
94.09%
94.89%
85.19%
% GW PWS
>MRL
20 1
85.15%
90.77%
93.60%
94.12%
94.87%
87.55%
ALL2
81.25%
87.59%
91.20%
92.82%
95.00%
84.34%
% SW PWS
>MRL
20 1
86.75%
90.71%
91.46%
97.35%
93.55%
91.61%
ALL2
85.51%
90.28%
88.21%
95.21%
94.85%
90.51%
% PWS
> 1/2 HRL
20 1
1.82%
1.51%
1.17%
1.49%
0.76%
1.65%
ALL2
1.63%
1.19%
0.93%
1.21%
0.57%
1.39%
% GW PWS
> 1/2 HRL
20 1
1.81%
1.53%
1.07%
1.84%
2.56%
1.69%
ALL2
1.62%
1.17%
0.90%
1.44%
2.50%
1.42%
% SW PWS
> 1/2 HRL
20 1
2.01%
1.41%
1.42%
1.14%
0.00%
1.37%
ALL2
1.81%
1.30%
0.98%
1.01%
0.00%
1.15%
% PWS
>HRL
20 1
0.47%
0.31%
0.32%
0.37%
0.00%
0.40%
ALL2
0.42%
0.26%
0.31%
0.27%
0.00%
0.34%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS
>HRL
20 1
0.46%
0.30%
0.15%
0.00%
0.00%
0.38%
ALL2
0.40%
0.25%
0.23%
0.00%
0.00%
0.33%
% SW PWS
>HRL
20 1
0.80%
0.40%
0.71%
0.76%
0.00%
0.58%
ALL2
0.72%
0.32%
0.49%
0.50%
0.00%
0.44%
MIN VALUE
ftjg/U
20 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
ftjg/U
20 1
672,000
470,000
360,000
408,000
346,000
488,000
ALL2
583,000
457,000
338,000
371,000
340,000
MAX VALUE
ftjg/U
20 1
2,437,000
3,880,000
1,217,000
1,619,000
635,000
457,000 3,880,000
ALL2
2,437,000
5,074,000
1,217,000
1,619,000
635,000
5,074,000
MIN DETECTS
ftjg/U
20 1
3.00
3.00
100.00
1.00
100.00
1.00
ALL2
3.00
2.80
10.40
1.00
3.40
1.00
MEDIAN DETECTS
ftjg/U
20 1
24,900
34,000
37,000
34,000
27,000
31,000
ALL2
23,000
30,000
30,700
26,000
23,000
23,000
Table E.3.b.2 SDWIS/FED (Round 2) Data- Sulfate Occurrence in Non-Transient Non-Community Water Systems by Population Served (HRL = 1,000,000 M9/L)
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
87.96%
89.97%
94.44%
100.00%
100.00%
88.24%
ALL2
85.72%
88.07%
95.45%
75.00%
100.00%
86.11%
% GW PWS
>MRL
20 1
87.94%
89.58%
93.75%
100.00%
100.00%
88.16%
ALL2
85.68%
87.88%
95.00%
66.67%
100.00%
86.03%
%SWPWS
>MRL
20 1
89.47%
100.00%
100.00%
100.00%
0.00%
92.31%
ALL2
88.61%
93.55%
100.00%
100.00%
0.00%
90.27%
% PWS
> 1/2 HRL
20 1
2.11%
1.95%
0.00%
0.00%
0.00%
2.08%
ALL2
1.98%
1.45%
0.00%
0.00%
0.00%
1.89%
% GW PWS
> 1/2 HRL
20 1
2.11%
2.02%
0.00%
0.00%
0.00%
2.09%
ALL2
1.97%
1.50%
0.00%
0.00%
0.00%
1.89%
% SW PWS
> 1/2 HRL
20 1
2.63%
0.00%
0.00%
0.00%
0.00%
1.92%
ALL2
2.53%
0.00%
0.00%
0.00%
0.00%
1.77%
% PWS
>HRL
20 1
0.39%
0.30%
0.00%
0.00%
0.00%
0.38%
ALL2
0.36%
0.22%
0.00%
0.00%
0.00%
0.34%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
%GWPWS>HRL
20 1
0.39%
0.31%
0.00%
0.00%
0.00%
0.38%
ALL2
0.37%
0.23%
0.00%
0.00%
0.00%
0.35%
% SW PWS > HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
ftjg/U
20 1
< 0.00
< 0.00
< 0.00
21,000.00
8,000.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
5.00
8,000.00
< 0.00
99% VALUE
ftjg/U
20 1
709,000
626,000
410,000
144,000
16,000
685,000
ALL2
680,000
600,000
410,000
144,000
16,000
660,000
MAX VALUE
ftjg/U
20 1
4,250,000
5,454,000
410,000
144,000
16,000
5,454,000
ALL2
4,250,000
5,454,000
410,000
144,000
16,000
5,454,000
MIN DETECTS
ftjg/U
20 1
100
200
1,200
21,000
8,000
100
ALL2
10
10
1,000
4,090
8,000
10
MEDIAN DETECTS
ftjg/U
20 1
27,000
24,000
12,000
82,500
11,000
26,000
ALL2
26,000
22,000
10,000
4,430
11,000
26,000
1. Analyses are based on data from the SDWIS/FED 20 State Cross-Section of: AK, AR, CO, KY, MA, MD, ME, Ml, MN, MO, NC, ND, NH, NM, OH, OK, OR, Rl, TX, WA.
2. Analyses are based on data from all 35 States in the SDWIS/FED database.
Sulfate data were analyzed using two different HRLs, and are, therefore, listed separately.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table E.4.a SDWIS/FED (Round 2) Data- Aldrin Occurrence in Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
0.00%
0.00%
0.29%
0.00%
0.00%
0.02%
ALL2
0.07%
0.25%
0.54%
1.36%
0.58%
0.25%
% GW PWS
>MRL
20 1
0.00%
0.00%
0.51%
0.00%
0.00%
0.03%
ALL2
0.07%
0.27%
0.53%
1.06%
0.00%
0.19%
% SW PWS
> MRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.17%
0.55%
1.60%
0.78%
0.57%
% PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.29%
0.00%
0.00%
0.02%
ALL2
0.07%
0.25%
0.54%
1.36%
0.58%
0.25%
% GW PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.51%
0.00%
0.00%
0.03%
ALL2
0.07%
0.27%
0.53%
1.06%
0.00%
0.19%
% SW PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.17%
0.55%
1.60%
0.78%
0.57%
% PWS
>HRL
20 1
0.00%
0.00%
0.29%
0.00%
0.00%
0.02%
ALL2
0.07%
0.25%
0.54%
1.36%
0.58%
0.25%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS
>HRL
20 1
0.00%
0.00%
0.51%
0.00%
0.00%
0.03%
ALL2
0.07%
0.27%
0.53%
1.06%
0.00%
0.19%
% SW PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.17%
0.55%
1.60%
0.78%
0.57%
MIN VALUE
(M9/U
20 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/U
20 1
< 1.00
< 30.00
< 2.00
< 2.00
< 2.00
< 2.00
ALL2
< 1.00
< 30.00
< 1.00
2.00
2.00
< 1.00
MAX VALUE
(M9/U
20 1
< 30.00
< 50.00
0.69
< 30.00
< 30.00
< 4.40
ALL2
0.21
0.68
0.69
0.18
0.43
4.40
MIN DETECTS
(M9/U
20 1
0.46
0.46
ALL2
0.10
0.09
0.17
0.07
0.07
0.07
MEDIAN DETECTS
(M9/U
20 1
0.58
0.58
ALL2
0.16
0.11
0.46
0.17
0.41
0.16
Table E.4.b SDWIS/FED (Round 2) Data- Aldrin Occurrence in Non-Transient Non-Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.14%
0.00%
0.00%
0.00%
0.12%
% GW PWS
>MRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.15%
0.00%
0.00%
0.00%
0.13%
% SW PWS
>MRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.14%
0.00%
0.00%
0.00%
0.12%
% GW PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.15%
0.00%
0.00%
0.00%
0.13%
%SWPWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.14%
0.00%
0.00%
0.00%
0.12%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
%GWPWS>HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.15%
0.00%
0.00%
0.00%
0.13%
% SW PWS > HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
(M9/U
20 1
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/L)
20 1
< 1.00
< 30.00
< 0.20
< 2.00
ALL2
< 1.00
< 2.00
< 0.20
< 0.00
< 1.00
MAX VALUE
(M9/L)
20 1
< 30.00
< 30.00
< 0.20
< 4.40
ALL2
0.10
< 30.00
< 0.20
< 0.00
4.40
MIN DETECTS
(M9/L)
20 1
ALL2
0.10
0.10
MEDIAN DETECTS
(M9/L)
20 1
ALL2
0.84
0.84
Massachusetts data not included in summary statistics for this contaminant.
1. Analyses are based on data from the SDWIS/FED 20 State Cross-Section of: AK, AR, CO, KY, MA, MD, ME, Ml, MN, MO, NC, ND, NH, NM, OH, OK, OR, Rl, TX, WA.
2. Analyses are based on data from all 35 States in the SDWIS/FED database.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table E.S.a SDWIS/FED (Round 2) Data- Dieldrin Occurrence in Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
0.07%
0.00%
0.16%
0.21%
0.00%
0.06%
ALL2
0.09%
0.11%
0.23%
1.27%
0.00%
0.18%
% GW PWS
>MRL
20 1
0.07%
0.00%
0.00%
0.45%
0.00%
0.06%
ALL2
0.09%
0.09%
0.18%
1.08%
0.00%
0.13%
% SW PWS
> MRL
20 1
0.00%
0.00%
0.40%
0.00%
0.00%
0.08%
ALL2
0.00%
0.18%
0.32%
1.42%
0.00%
0.44%
% PWS
> 1/2 HRL
20 1
0.07%
0.00%
0.16%
0.21%
0.00%
0.06%
ALL2
0.09%
0.11%
0.23%
1.27%
0.00%
0.18%
% GW PWS
> 1/2 HRL
20 1
0.07%
0.00%
0.00%
0.45%
0.00%
0.06%
ALL2
0.09%
0.09%
0.18%
1.08%
0.00%
0.13%
% SW PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.40%
0.00%
0.00%
0.08%
ALL2
0.00%
0.18%
0.32%
1.42%
0.00%
0.44%
% PWS
>HRL
20 1
0.07%
0.00%
0.16%
0.21%
0.00%
0.06%
ALL2
0.09%
0.11%
0.23%
1.27%
0.00%
0.18%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS
>HRL
20 1
0.07%
0.00%
0.00%
0.45%
0.00%
0.06%
ALL2
0.09%
0.09%
0.18%
1.08%
0.00%
0.13%
% SW PWS
>HRL
20 1
0.00%
0.00%
0.40%
0.00%
0.00%
0.08%
ALL2
0.00%
0.18%
0.32%
1.42%
0.00%
0.44%
MIN VALUE
(M9/U
20 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/U
20 1
< 0.20
< 20.00
< 20.00
< 20.00
< 0.30
< 1.00
ALL2
< 0.20
< 1.00
< 0.20
0.88
< 0.30
< 0.30
MAX VALUE
(M9/U
20 1
0.08
< 50.00
0.09
0.10
20.00
4.40
ALL2
0.10
0.04
0.10
0.10
20.00
4.40
MIN DETECTS
(M9/U
20 1
0.02
0.09
0.10
0.02
ALL2
0.02
0.01
0.09
0.01
0.01
MEDIAN DETECTS
(M9/U
20 1
0.05
0.09
0.10
0.08
ALL2
0.08
0.02
0.10
1.65
0.08
Table E.S.b SDWIS/FED (Round 2) Data- Dieldrin Occurrence in Non-Transient Non-Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
0.09%
0.40%
0.00%
0.12%
ALL2
0.24%
0.33%
0.00%
0.00%
0.25%
% GW PWS
>MRL
20 1
0.09%
0.43%
0.00%
0.13%
ALL2
0.25%
0.36%
0.00%
0.00%
0.26%
% SW PWS
>MRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
> 1/2 HRL
20 1
0.09%
0.40%
0.00%
0.12%
ALL2
0.24%
0.33%
0.00%
0.00%
0.25%
% GW PWS
> 1/2 HRL
20 1
0.09%
0.43%
0.00%
0.13%
ALL2
0.25%
0.36%
0.00%
0.00%
0.26%
%SWPWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
20 1
0.09%
0.40%
0.00%
0.12%
ALL2
0.24%
0.33%
0.00%
0.00%
0.25%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
%GWPWS>HRL
20 1
0.09%
0.43%
0.00%
0.13%
ALL2
0.25%
0.36%
0.00%
0.00%
0.26%
% SW PWS > HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
(M9/U
20 1
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/L)
20 1
< 1.00
< 20.00
< 0.20
< 1.00
ALL2
< 0.20
< 1.00
< 0.20
< 0.00
< 1.00
MAX VALUE
(M9/L)
20 1
1.36
0.35
< 0.20
4.40
ALL2
1.36
0.35
< 0.20
< 0.00
4.40
MIN DETECTS
(M9/L)
20 1
0.02
0.20
0.02
ALL2
0.02
0.20
0.02
MEDIAN DETECTS
(M9/L)
20 1
0.18
0.27
0.20
ALL2
0.20
0.27
0.20
Massachusetts data not included in summary statistics for this contaminant.
1. Analyses are based on data from the SDWIS/FED 20 State Cross-Section of: AK, AR, CO, KY, MA, MD, ME, Ml, MN, MO, NC, ND, NH, NM, OH, OK, OR, Rl, TX, WA.
2. Analyses are based on data from all 35 States in the SDWIS/FED database.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table E.6.a SDWIS/FED (Round 2) Data- Metribuzin Occurrence in Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
> MRL
20 1
0.02%
0.00%
0.00%
0.00%
0.00%
0.01%
ALL2
0.09%
0.15%
0.23%
2.49%
2.79%
0.33%
% GW PWS
> MRL
20 1
0.02%
0.00%
0.00%
0.00%
0.00%
0.01%
ALL2
0.10%
0.05%
0.00%
0.76%
0.00%
0.10%
% SW PWS
>MRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.49%
0.51%
3.57%
3.57%
1.35%
% PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% GW PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
(M9/L)
20 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
ftjg/U
20 1
< 2.00
< 2.00
< 2.00
< 2.00
< 2.00
< 2.00
ALL2
< 2.00
< 2.00
< 2.00
< 10.00
< 2.00
< 2.00
MAX VALUE
ftjg/D
20 1
0.10
< 50.00
< 100.00
< 10.00
< 10.00
2.00
ALL2
3.00
3.00
3.00
3.00
3.00
3.00
MIN DETECTS
ftjg/D
20 1
0.10
0.10
ALL2
0.10
1.00
1.00
1.00
1.00
0.10
MEDIAN DETECTS
ftjg/D
20 1
0.10
0.10
ALL2
1.00
1.00
1.00
1.05
1.00
1.00
Table E.6.b SDWIS/FED (Round 2) Data- Metribuzin Occurrence in Non-Transient Non-Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.15%
0.43%
0.00%
0.00%
0.18%
% GW PWS
>MRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.15%
0.47%
0.00%
0.00%
0.19%
%SWPWS
>MRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% GW PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS > HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS > HRL
20 1
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
(M9/L)
20 1
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
ftjg/U
20 1
< 2.00
< 2.00
< 2.00
< 2.00
ALL2
< 2.00
< 2.00
< 2.00
< 0.0002
< 2.00
MAX VALUE
(M9/L)
20 1
< 1010.00
< 10.00
< 2.00
< 1.10
ALL2
3.00
3.00
< 2.00
< 0.0002
3.00
MIN DETECTS
ftjg/D
20 1
ALL2
0.10
1.00
0.10
MEDIAN DETECTS
ftjg/D
20 1
ALL2
1.00
1.00
1.00
Massachusetts data not included in summary statistics for this contaminant.
1. Analyses are based on data from the SDWIS/FED 20 State Cross-Section of: AK, AR, CO, KY, MA, MD, ME,
2. Analyses are based on data from all 35 States in the SDWIS/FED database.
, MN, MO, NC, ND, NH, NM, OH, OK, OR, Rl, TX, WA.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table E.7.a SDWIS/FED (Round 2) Data- Hexachlorobutadiene Occurrence in Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
0.27%
0.12%
0.16%
0.38%
0.55%
0.23%
ALL2
0.25%
0.13%
0.14%
0.34%
0.47%
0.22%
% GW PWS
>MRL
20 1
0.19%
0.12%
0.12%
0.27%
0.00%
0.17%
ALL2
0.18%
0.13%
0.10%
0.23%
0.00%
0.16%
% SW PWS
> MRL
20 1
1.86%
0.14%
0.25%
0.49%
0.74%
0.65%
ALL2
1.82%
0.13%
0.23%
0.44%
0.64%
0.61%
% PWS
> 1/2 HRL
20 1
0.07%
0.10%
0.16%
0.26%
0.55%
0.10%
ALL2
0.07%
0.11%
0.14%
0.23%
0.47%
0.09%
% GW PWS
> 1/2 HRL
20 1
0.05%
0.12%
0.12%
0.27%
0.00%
0.08%
ALL2
0.05%
0.13%
0.10%
0.23%
0.00%
0.08%
% SW PWS
> 1/2 HRL
20 1
0.41%
0.00%
0.25%
0.24%
0.74%
0.23%
ALL2
0.40%
0.00%
0.23%
0.22%
0.64%
0.22%
% PWS
>HRL
20 1
0.02%
0.02%
0.00%
0.00%
0.00%
0.02%
ALL2
0.02%
0.02%
0.00%
0.00%
0.00%
0.02%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS
>HRL
20 1
0.01%
0.03%
0.00%
0.00%
0.00%
0.01%
ALL2
0.01%
0.03%
0.00%
0.00%
0.00%
0.01%
% SW PWS
>HRL
20 1
0.21%
0.00%
0.00%
0.00%
0.00%
0.05%
ALL2
0.20%
0.00%
0.00%
0.00%
0.00%
0.04%
MIN VALUE
(M9/U
20 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/U
20 1
< 1.00
< 1.00
< 1.00
< 1.00
< 1.00
< 1.00
ALL2
< 1.00
< 1.00
< 1.00
< 1.00
< 1.00
< 1.00
MAX VALUE
(M9/U
20 1
1.50
1.06
0.50
0.80
0.60
1.50
ALL2
1.50
1.06
0.50
0.80
0.60
1.50
MIN DETECTS
(M9/L)
20 1
0.10
0.20
0.50
0.20
0.60
0.10
ALL2
0.10
0.20
0.50
0.20
0.60
0.10
MEDIAN DETECTS
(M9/L)
20 1
0.20
0.50
0.50
0.50
0.60
0.30
ALL2
0.20
0.50
0.50
0.50
0.60
0.20
Table E.7.b SDWIS/FED (Round 2) Data- Hexachlorobutadiene Occurrence in Non-Transient Non-Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
0.05%
0.00%
0.00%
0.00%
0.05%
ALL2
0.05%
0.00%
0.00%
0.00%
0.04%
% GW PWS
>MRL
20 1
0.05%
0.00%
0.00%
0.00%
0.05%
ALL2
0.05%
0.00%
0.00%
0.00%
0.04%
% SW PWS
>MRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
> 1/2 HRL
20 1
0.04%
0.00%
0.00%
0.00%
0.03%
ALL2
0.03%
0.00%
0.00%
0.00%
0.03%
% GW PWS
> 1/2 HRL
20 1
0.04%
0.00%
0.00%
0.00%
0.03%
ALL2
0.03%
0.00%
0.00%
0.00%
0.03%
%SWPWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
20 1
0.02%
0.00%
0.00%
0.00%
0.02%
ALL2
0.02%
0.00%
0.00%
0.00%
0.01%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
%GWPWS>HRL
20 1
0.02%
0.00%
0.00%
0.00%
0.02%
ALL2
0.02%
0.00%
0.00%
0.00%
0.01%
% SW PWS > HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
(M9/L)
20 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/L)
20 1
< 1.00
< 1.00
< 1.00
< 1.00
< 1.00
ALL2
< 1.00
< 1.00
< 1.00
< 1.00
< 1.00
MAX VALUE
(M9/L)
20 1
1.40
< 1.00
< 1.00
< 1.00
1.40
ALL2
1.40
< 1.00
< 1.00
< 1.00
1.40
MIN DETECTS
(M9/L)
20 1
0.10
0.10
ALL2
0.10
0.10
MEDIAN DETECTS
(M9/L)
20 1
0.50
0.50
ALL2
0.50
0.50
New Hampshire data not included in summary statistics for this contaminant.
1. Analyses are based on data from the SDWIS/FED 20 State Cross-Section of: AK, AR, CO, KY, MA, MD, ME, Ml, MN, MO, NC, ND, NH, NM, OH, OK, OR, Rl, TX, WA.
2. Analyses are based on data from all 35 States in the SDWIS/FED database.
-------
Occurrence of 1998 CCL Priority Contaminants in Public Water Systems
Table E.S.a SDWIS/FED (Round 2) Data- Naphthalene Occurrence in Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
0.76%
0.50%
1.36%
2.28%
3.85%
0.84%
ALL2
0.70%
0.54%
1.23%
2.25%
3.76%
0.81%
% GW PWS
>MRL
20 1
0.67%
0.43%
0.84%
1.59%
2.17%
0.65%
ALL2
0.62%
0.47%
0.80%
1.61%
3.64%
0.63%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% GW PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS
>MRL
20 1
2.47%
0.80%
2.38%
2.91%
4.41%
2.09%
ALL2
2.41%
0.89%
2.20%
2.86%
3.80%
2.04%
MIN VALUE
(M9/U
20 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
% PWS
> 1/2 HRL
20 1
0.00%
0.02%
0.00%
0.00%
0.00%
0.01%
ALL2
0.00%
0.02%
0.00%
0.00%
0.00%
0.01%
% GW PWS
> 1/2 HRL
20 1
0.00%
0.03%
0.00%
0.00%
0.00%
0.01%
ALL2
0.00%
0.02%
0.00%
0.00%
0.00%
0.01%
%SWPWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
0.00%
99% VALUE
(M9/U
20 1
< 2.00
< 2.00
2.00
2.00
1.00
< 2.00
ALL2
< 2.00
< 2.00
2.00
2.00
1.00
< 2.00
MAX VALUE
(M9/U
20 1
18.00
80.00
2.00
5.00
1.30
80.00
ALL2
18.00
80.00
2.00
5.00
1.30
80.00
MIN DETECTS
(M9/U
20 1
0.07
0.10
0.09
0.08
0.10
0.07
ALL2
0.07
0.10
0.09
0.08
0.10
0.07
MEDIAN DETECTS
(M9/L)
20 1
0.80
0.95
0.51
0.60
0.32
0.68
ALL2
0.80
0.90
0.53
0.61
0.34
0.80
Table E.S.b SDWIS/FED (Round 2) Data- Naphthalene Occurrence in Non-Transient Non-Community Water Systems by Population Served
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
% PWS
>MRL
20 1
0.53%
0.45%
0.00%
33.33%
0.53%
ALL2
0.51%
0.42%
0.00%
25.00%
0.51%
% GW PWS
> MRL
20 1
0.54%
0.48%
0.00%
50.00%
0.55%
ALL2
0.52%
0.45%
0.00%
33.33%
0.52%
% SW PWS
> MRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
> 1/2 HRL
20 1
0.02%
0.00%
0.00%
0.00%
0.02%
ALL2
0.02%
0.00%
0.00%
0.00%
0.01%
% GW PWS
> 1/2 HRL
20 1
0.02%
0.00%
0.00%
0.00%
0.02%
ALL2
0.02%
0.00%
0.00%
0.00%
0.01%
% SW PWS
> 1/2 HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% PWS
>HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
POPULATION
SERVED
<500
501-3,300
3,301-10,000
10,001-50,000
> 50,000
TOTAL
%GWPWS>HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
% SW PWS > HRL
20 1
0.00%
0.00%
0.00%
0.00%
0.00%
ALL2
0.00%
0.00%
0.00%
0.00%
0.00%
MIN VALUE
(M9/L)
20 1
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
ALL2
< 0.00
< 0.00
< 0.00
< 0.00
< 0.00
99% VALUE
(M9/L)
20 1
< 2.00
< 2.00
< 2.00
3.00
< 2.00
ALL2
< 2.00
< 2.00
< 2.00
3.00
< 2.00
MAX VALUE
(M9/L)
20 1
90.00
0.80
< 2.00
3.00
90.00
ALL2
90.00
0.80
< 2.00
3.00
90.00
MIN DETECTS
(M9/L)
20 1
0.10
0.50
3.00
0.10
ALL2
0.10
0.50
3.00
0.10
MEDIAN DETECTS
(M9/L)
20 1
0.94
0.70
3.00
0.90
ALL2
0.94
0.70
3.00
0.94
New Hampshire data not included in summary statistics for this contaminant.
1. Analyses are based on data from the SDWIS/FED 20 State Cross-Section of: AK, AR, CO, KY, MA, MD, ME, Ml, MN, MO, NC, ND, NH, NM, OH, OK, OR, Rl, TX, WA.
2. Analyses are based on data from all 35 States in the SDWIS/FED database.
------- |