PB94-964008
EPA/ROD/R04-94/174
July 1994
EPA Superfund
Record of Decision:
National Starch and Chemical
Company Site, Salisbury, NC
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RECORD OF DECISION
REMEDIAL ALTERNATIVE SELECTION
OPERABLE UNIT #3
NATIONAL STARCH & CHEMICAL COMPANY SITE
SALISBURY, ROWAN COUNTY
NORTH CAROLINA
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u.S. ENVIRONMENTAL PROTECTION AGENCY
REGION IV
ATLANTA, GEORGIA
OCTOBER 1993
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DECLARATION FOR THE
RECORD OF DECISION
SITE NAME AND LOCA110N
Chemical Starch & Chemical Company
Cedar Springs Road, Salisbury, Rowan County, North Carolina
STATEMENT OF BASIS AND PURPOSE
This decision document presents the Operable Unit Three Remedial Action for the National Starch
& Chemical Company Superfund Site in Salisbury, North Carolina, chosen in accordance with the
Comprehensive Environmental Response, Compensation, and liability Act of 1980, as amended
by the Superfund Amendments and Reauthorization Act of 1986 and, to the extent practicable,
the National Oil and Hazardous Substances Contingency Plan. This decision is based on the
Administrative Record file for this Site.
The State of North Carolina conditionally concurs with the selected remedy for Operable Unit
Three. State comments on this RAcord of Decision, as well as EPA's responses to those
comments, can be found in Appendix A of this document
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this Site, if not addressed by
implementing the response action selected in this Record of Decision, may present an imminent
and substantial endangerment to public health, welfare, or the environment. Presently, no
unacceptable current risks were identified associated with the National Starch & Chemical
Company Site. The principle threat pertains to the future and potential use of the groundwater
beneath and downgradient of the Site and the potential adverse impact contaminated soils will
have on the quality of the groundwater.
DESCRIP110N OF THE SELECTED REMEDY
This Operable Unit is the third of four Operable Units for this Site. The first two Operable Units
addressed the contamination associated with the Trench Area. This Operable Unit and the fourth
Operable Unit will address the contamination associated with the active production area of the
National Starch & Chemical Company facility and the wastewater treatment lagoon area.
This Operable Unit, Operable Unit #3, will permanently remove contaminants in the groundwater
through groundwater extraction and on-site, above-ground treatment with the discharge of the
treated groundwater to be combined with the facility's effluent to the City of Salisbury publicly
owned treatment works. Operable Unit #4 will address the contaminated soils In this portion of
the Site.
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The major components of Operable Unit #3 Remedial Action include:
.
Design and implementation of the specified groundwater remediation system. The
groundwater remediation alternative includes extraction wells to remove contaminated
groundwater, an air stripper to remove the volatile organic contaminants from the
extracted groundwater, control of emissions from the air stripper to the atmosphere
through vapor-phase carbon adsorption filters, and discharging treated groundwater to the
City of Salisbury publicly owned treatment works system.
.
Long-term monitoring of the groundwater and surface water and sediment in the Northeast
Tributary.
.
Implementation of a deed restriction on the property as an institutional control.
.
Review and evaluate the existing groundwater monitoring system to insure proper
monitoring of both groundwater quality and groundwater flow so that the effectiveness of
the groundwater extraction system can be evaluated. Additional monitoring wells and/or
piezometers will be added to mitigate any deficiencies.
.
Performance of five (5) year reviews in accordance to Comprehensive Environmental
Response, Compensation, and Uability Act of 1980.
ADDmONAL SAMPLING AND MONITORING
Additional monitoring wells shall be installed during the Remedial Design to further delineate the
vertical extent of groundwater contamination in the bedrock. Additional aquifer tests may also be
needed in order to properly design the selected remedy. And in order to establish a broader
database on groundwater quality and groundwater levels, samples and groundwater level
readings will be collected and analyzed on a regular basis prior to implementation of the Remedial
Action.. .
STATUTORY DETERMINA110NS
The selected remedy is protective of human health and the environment, complies with federal
and state requirements that are legally applicable or relevant and appropriate to the remedial
action, and is cost-effective. This remedy utilizes permanent solutions and alternative treatment.
technology to the maximum extent practicable, and satisfies the statutory preference for remedies
that employ treatment that reduces toxicity, mobility, or volume as a principal element. Since this
remedy may result In hazardous substances remaining in the groundwater on-site above the
chemical-specific applicable requirements, a review will be conducted within five years after
commencement of remedial action to ensure that the remedy continues to provide adequate
protection of human health and the environment.
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Patrick M. Tobin
Acting Regional Administrator
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DECISION SUMMARY
RECORD OF DECISION
REMEDIAL ALTERNATIVE SELECTION
OPERABLE UNIT #3
NATIONAL STARCH & CHEMICAL COMPANY SITE
SALISBURY, ROWAN COUNTY
NORTH CAROLINA
PREPARED By:
u.S. ENVIRONMENTAL PROTECTION AGENCY
REGION IV .
ATLANTA, GEORGIA
OCTOBER 1993
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TABLE OF CONTENTS
SECTION
PAGE No.
1.0 SITE NAME, LOCATION, AND DESCRIPTION
..................................... 1
2.0 SITE HISTORY AND ENFORCEMENT ACTIVITIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1
3.0 HIGHLIGHTS OF COMMUNITY PARTICIPATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5
4.0 SCOPE AND ROLE OF OPERABLE UNIT WITHIN SITE STRATEGY. . . . . . . . . . . . . . . . . . .. 6
5.0 SUMMARY OF SITE CHARACTERISTICS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 7
5.1 SOILS[[[ 8
5.2 GROUNDWATER[[[ 11
5.2.1 SAPROLITE GROUNDWATER. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .. 12
5.2.2 BEDROCK GROUNDWATER. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .. 13
5.3 SURFACE WATER AND SEDIMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 13
5.4 HYDROGEOLOGICAL SETTING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 34
5.5 PATHWAYS AND ROUTES OF EXPOSURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 35
6.0 SUMMARY OF SITE RISKS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 43
6.1 CONTAMINANTS OF CONCERN.... . . . . . . . . . .. . .... . . . . ... . . .. . . . . ... . ... 43
6.2 EXPOSURE ASSESSMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 44
6.3 TOXICITY ASSESSMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 45
6.4 RISK CHARACTERIZATION.. . .. . .. . . . . . . . . . ., . . . . . . " .,.. . . . .. .. .. . . .. .. 45
6.5 RISK UNCERTAINTY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 46
6.6 ENVIRONMENTAL RISK. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 47
6.7 SUMMARY[[[ 61
7.0 REMEDIAL ACTION OBJECTIVES. . . .. . . . . . . . . . . . . . . . .... ..... . . . ... . . .. . .. . .. 61
7.1 APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS (ARARS) . ..... .. 61
7.2 EXTENT OF CONTAMINATION. ... . . . . . .. . . . . . .. . . ... . .... ... ... . . .. ...... 62
8.0 DESCRIPTION OF ALTERNATIVES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 62
8.1 REMEDIAL ALTER~TIVES TO ADDRESS .GROUNDWATER CONTAMINATION....... 62
8.1.1 ALTERNATIVE GWP1 IGWL 1: No action.. .. .. .. .. .. .. .. .. .. .. . .. .. .. ... 63
8.1.2 ALTERNATIVE GWP2IGWl2: Long Term Monitoring and Fencing
A Portion Of Northeast Tributary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 67
8.1.3 ALTERNATIVE GWP3IGWL3: Institutional Controls, Long Term
Monitoring, and Fencing A Portion Of Northeast Tributary. . . . . . . . . . . . . . . . . . .. 67
8.1.4 ALTERNATIVE GWP4A1GWL4A: Groundwater Extraction Through
Wells; Treatment by Air Stripping with Vapor-Phase CarbQn Adsorption;
and Discharge to POTW ............................................ 68
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TABLE OF CONTENTS
SECTION
PAGE Nb.
8.2 REMEDIAL ALTERNATIVES TO ADDRESS SURFACE WATER AND
SEDIMENT CONTAMINATION............................................ 69
8 .2.1 ALTERNATIVE SW /SE-1: No Action. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69
8.2.2 ALTERNATIVE SW/SE-2: Long-Term Monitoring. . . . . . . . . . . . . . . . . . . . . . . . .. 69
9.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES....................... 69
9.1 THRESHOLD CRITERIA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69
9.1.1 OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT. . . . . .. 70
9.1.2 COMPLIANCE WITH APPLICABLE OR RELEVANT AND APPROPRIATE
REQUIREMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 70
9.2 PRIMARY BALANCING CRITERIA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 71
9.2.1 LONG-TERM EFFECTIVENESS AND PERMANENCE. . . . . . . . . . . . . . . . . . . . .. 71
9.2.2 REDUCTION OF TOXICITY, MOBILITY, OR VOLUME. . . . . . . . . . . . . . . . . . . . .. 72
9.2.3 SHORT-TERM EFFECTIVENESS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 7:2
9.2.4 IMPLEMENTABILITY............................................... 72
9.2.5 COST[[[ 72
9.3 MODIFYING CRITERIA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 78
9.3.1 STATE OF NORTH CAROLINA ACCEPTANCE. . . . . . . . . . . . . . . . . . . . . . . . . .. 7:8
9.3.2 COMMUNITY ACCEPTANCE. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .. 7:8
10.0 DESCRIPTION OF THE SELECTED REMEDY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 79
10.1 PERFORMANCE STANDARDS TO BE ATTAINED. . . . . . . . . . . . . . . . . . . . . . . . . . .. 79
10.2 GROUNDWATER REMEDIATION. . . . . . . . . . . . . . .. .. .. . . . . ... .. .. .. ... . .... 80
10.3 NORTHEAST TRIBUTARY SURFACE WATER/SEDIMENT REMEDIATION. . . . . . . . .. 84
10.4 MONITOR EXISTING CONDITIONS/ADDITIONAL DATA REQUIREMENTS.......... 84
10.5 COST[[[ '. .. 85
11.0 STATUTORY DETERMINATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 85
11.1 PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT.... . .... .. .'.. . . . .. 86
11.2 COMPLIANCE WITH ARARS ....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 86
11.3 COST-EFFECTIVENESS........... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 86
11.4 UTILIZATION OF PERMANENT SOLUTIONS AND ALTERNATIVE '
TREATMENT TECHNOLOGIES OR RESOURCE TECHNOLOGIES '
TO THE MAXIMUM EXTENT PRACTICABLE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 86
11.5 PREFERENCE FOR TREATMENT AS A PRINCIPAL ELEMENT.. . ... .......... .. 86
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APPENDICES
APPENDIX A CONCURRENCE LETTER FROM THE STATE OF NORTH CAROLINA AND
RESPONSE FROM THE AGENCY
APPENDIX B PROPOSED PLAN FACT SHEET
APPENDIX C RESPONSIVENESS SUMMARY
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LIST OF FIGURES
FIGURE 1
FIGURE 2
FIGURE 3
FIGURE 4
FIGURE 5
FIGURE 6
FIGURE 7
FIGURE 8
FIGURE 9
FIGURE 10
FIGURE 11
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FIGURE
TITLE
PAGE No.
SITE LOCATION MAp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2
LOCATION OF FACILmES THAT COMPRISE OPERABLE UNIT 13 . . . . .. . . . . . .. 3
DISTRIBUTION OF 1,2-DCA IN THE WATER TABLE ZONE OF THE AQUIFER. . .. 14
DISTRIBUTION OF 1,2-DCA IN THE SAPROLITE ZONE OF THE AQUIFER. . . . .. 15
SAMPLING LOCATIONS FOR GROUNDWATER (WATER TABLE) VIA
WELLPOINTS AND CONCENTRATIONS OF 1,2-DICHLOROETHANE
DETECTED AT EACH WELLPOINT ................................. 22
SAMPLING LOCATIONS FOR GROUNDWATER (SAPROLITE ZONE)
VIA PUSH-POINT SAMPLER, TEMPORARY MONITORING WELLS, AND
SCREENED WATER SAMPLER AND CORRESPONDING CONCENTRATIONS
OF 1,2-DICHLOROETHANE DETECTED AT EACH LOCATION. . . . . . . . . .. . . . .. 23
CONCENTRATIONS AND ESTIMATED EXTENT OF 1,2-DICHLOROETHANE
CONTAMINATION IN THE BEDROCK ZONE OF THE AaUIFER ............... 26
SURFACE WATER SAMPLING LOCATIONS AND CONCENTRATIONS
OF 1,2-DICHLOROETHANE FROM L~ST SAMPLING EFFORT ON
THE NORTHEAST TRIBUTARY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 32
SEDIMENT SAMPLING LOCATIONS AND CONCENTRATIONS OF
1,2-DICHLOROETHANE FROM LAST SAMPLING EFFORT ON
THE NORTHEAST TRIBUTARY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 33
ORIENTATION OF HYDROGEOLOGICAL CROSS-SECTIONAL A-A' . . . . . . . . . . . .. 37
HYDROGEOLOGICAL CROSS-SECTION A-A' . . . . . . . . . . . . . . . . . . . . . . . . . .. 38
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..
LIST OF TABLES
TABLE
TITLE
PAGE No.
TABLE 1 RANGE AND FREQUENCY OF DETECTION OF ORGANIC
CONTAMINANTS AND INORGANIC CONSTITUENTS FOUND IN THE
ENVIRONMENTAL MEDIA SAMPLED 0 0 0 . 0 0 0 . 0 . . 0 0 0 0 . 0 . . 0 . 0 . . . 0 . . . . 0 . .. 9
TABLE 2 FREQUENCY OF DETECTION AND CONCENTRATIONS OF
ORGANIC CONTAMINANTS DETECTED IN GROUNDWATER
SAMPLES COLLECTED FROM WELLPOINTS (WATER TABLE)
AND PERMANENT MONITORING WELLS NS-13 AND NS-14 .. . . . 0 0 0 . 0 0 . . . 0.. 16
TABLE 3 FREQUENCY OF DETECTION AND CONCENTRATIONS OF VOLATILE
ORGANICS DATA FOR GROUNDWATER SAMPLES COLLECTED FROM
PUSH-POINT SAMPLER, TEMPORARY MONITORING WELLS, AND
SCREENED WATER SAMPLER 000000.00000000.00.0'.'.0...000.. 0 .0' 18
TABLE 4 FREQUENCY OF DETECTION, CONTAMINANTS DETECTED, AND
MOST STRINGENT PROMULGATED STANDARDS FOR CONTAMINANTS
DETECTED IN THE SAPROLITE ZONE OF THE AQUIFER 0 . 0 0 0 . . . . 0 0 0 0 0 . . 0 . . 0 24
TABLE 5 FREQUENCY OF DETECTION, CONCENTRATIONS DETECTED, AND
. MOST STRINGENT PROMULGATED GROUNDWATER STANDARDS FOR
CONTAMINANTS DETECTED IN THE BEDROCK ZONE OF THE AQUIFER 0.... 0 0 0 0 27
TABLE 6 SUMMARY OF DETECTABLE CONCENTRATIONS OF 1,2-DICHLOROETHANE
IN SURFACE WATER, SEDIMENT, AND SOIL SAMPLING OF THE NORTHEAST
TRIBUTARY. . . . . . . . . 0 . 0 . 0 0 . . 000 0 0 0 0 00 0 0 0 0 . 0 . . . 0 . 0 0 . . 000 0 0 0 . .. 29
TABLE 7 CONCENTRATIONS OF ORGANICS AND INORGANICS IN SURFACE
WATER AND SEDIMENT FROM LOCATIONS SW/SE-12 AND SW/SE-13 .000000. 31
TABLE 8 LIST OF CHEMICALS OF CONCERN IN THE GROUNDWATER POSING
RISK AND THE ASSOCIATED UPPER CONFIDENCE LIMITS (95%)
EXPOSURE POINT CONCENTRATION. 0 0 0 0 . 0 . 0 . 0 0 . . 0 0 . . . . 0 0 . 0 0 0 . 0 . 0 . o. 39
TABLE 9 POTENTIAL CURRENT AND FUTURE EXPOSURE PATHWAYS OF HUMAN
EXPOSURE To CONTAMINANTS o. 0 . 0 0 0 . . 0 . 0 0 0 0 0 . 0 0 . . 0 0 0 0 . 0 0 0 . . 0 0 . o. 40
TABLE 10 PARAMETERS USED To DESCRIBE EXPOSURES To SITE-RELATED
CHEMICALS OF CONCERN 0 0 . . . . . 0 0 0 0 . 0 0 0 0 . 0 0 . . . . . 0 . 0 . . . 0 0 . . 0 0 . o. 48
TABLE 13 SUMMARY OF CANCER RISK AND NONCANCER HI VALUE. . . 0 . 0 . . . 0 0 . . 0 0 0 .. 60
TABLE 14 REMEDIAL ACTION OBJECTIVES AND ASSOCIATED GENERAL RESPONSE
. ACTIONS 0 0 . 0 Co . 0 . . 0 0 0 0 0 . 0 . 0 0 0 . 0 . 0 . . 0 0 0 0 0 . 0 . 0 0 0 . 0 . . . . . . . 0 . . o. 64
TABLE 15 SECONDARY SCREENING OF TECHNOLOGIES AND PROCESS OPTIONS
FOR GROUNDWATER 00' 0 0 0 0 0 . . 0 . 0 . 0 0 . 0 . 0 0 0 0 0 0 . 0 0 0 0 . . 0 0 0 . . 0 0 . 0 o. 65
TABLE 16 SUMMARY OF THE THRESHOLD CRITERIA EVALUATION FOR THE
ALTERNATIVES 0 0 0 0 . 0 0 0 0 . 0 0 0 0 0 0 0 . . . 0 0 0 0 0 0 0 0 0 . 0 0 0 . 0 0 0 0 0 . . . 0 0 . o. 73
TABLE 17 'ApPLICABLE OR RELEVANT AND ApPROPRIATE REQUIREMENTS. 0 0 0 0 0 . . . . 0 . .. 74
TABLE 18 SUMMARY OF PRIMARY BALANCING CRITERIA EVALUATION OF THE
AL TERNATIVES ............... 0 0 . . . . . 0 . 0 . . 0 . 0 0 . . 0 0 0 0 0 0 0 0 0 0 0 0 . 0 76
TABLE 19 PERFORMANCE STANDARDS AND CORRESPONDING RISKS FOR OU #3 . 0 0 0 . . 0 . 0 81
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LIST OF ACRONYMS
AOC
ARAR
AWac
CAA
CERCLA
i .
cm/sec
CD
CRP
CSF
CWA
1,2-DCA
ESD
EPA
FS
GAC
gpm
HI
HQ
HRS
LDRs
MCLs
MCLGs
mglkg
mph
~
NCAC
NCDEHNR '-
NCGS
NCP
ND
NOAA
NPDES
NPL
NSC
NSCC
O&M
OU
POiW
ppb
ppm
PQL
PRP
PW
RA
RCRA
.... -..-.'.. -- .
Administrative Order on Consent
Applicable or Relevant and Appropriate Federal, State or Local
Requirements .
Ambient Water Quality Criteria
Clean Air Act
Comprehensive Environmental Response, Compensation, and Liability Act
of 1980 (Superfund)
centimeters per second
Consent Decree
Community Relations Plan
Cancer Slope Factor
Clean Water Act
1 ,2-Dichloroethane
Explanation of Significant Difference
Environmental Protection Agency
Feasibility Study
Granular Activated Carbon
gallons per minute
Hazard Index
Hazard Quotient
Hazardous Ranking System
Land Disposal Restrictions
Maximum Contaminant Levels
Maximum Contaminant Level Goals
milligrams per kilogram
. miles per hour
Monitoring Well
North Carolina Administrative Code
North Carolina Department of Environment, Health, and Natural Resources
North Carolina General Statute
National Oil and Hazardous Substances Pollution Contingency Plan
Not Detected
National Oceanic and Atmospheric Administration
National Pollution Discharge Elimination System
National Priority List
National Starch & Chemical Company
National Starch & Chemical Company
Operation and Maintenance
Operable Unit
Publicly Owned Treatment Wor1
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RfD
RD
RI
RME
ROD
SARA
SDWA
SVOCs
TAL
TBC
TCl
TClP
TMV
~glkg
~"
VOCs
Reference Dose
Remedial Design
Remedial Investigation
Reasonable Maximum Exposure
Record of Decision
Superfund Amendments and Reauthorization Act of 1986
Safe Drinking Water Act
Semi-volatile Organic Compounds
Target Analyte list
To Be Considered
Target Compound list
Toxicity Characteristic leaching Procedure
Toxicity, Mobility, or Volume
micrograms per kilogram
micrograms per liter
Volatile Organic Compounds
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RECORD OF DECISION
SUMMARY OF REMEDIAL ALTERNATIVE SELECTION
OPERABLE UNIT THREE
NATIONAL STARCH & CHEMICAL COMPANY SUPERFUND SITE
SALISBURY, ROWAN COUNTY, NORTH CAROLINA
1.0 SITE NAME, LOCATION. AND DESCRIPTION
The National Starch & Chemical Company (NSCC Site or the WSiteW) Site is located on Cedar
Springs Road in Salisbury, Rowan County, North Carolina. The Site is approximately 5 miles
south of the City of Salisbury at latitude 35°37'49w north and longitude 80032'03w west. Figure
1 shows the location of the Site with respect to the City of Salisbury. The areas of the Site that
compose Operable Unit (OU) #3 are shown in FIgure 2. OU #3 includes the following areas of
the NSCC facility: Area 2, the parking lot, the Northeast Tributary, and the wastewater treatment
lagoons. Area 2 consists of the following operations: Area 2 Reactor Room, the Tank Room, Raw
Material Bulk Storage, and the Warehouse. The lagoon area includes three lagoons which were
constructed between 1969-1970 as unlined lagoons. Wastewater was pumped into Lagoon 2
from 1970 to 1978. In 1978, Lagoon 1 was put into service and Lagoon 3 was lined with
concrete. Lagoons 1 and 2 were originally used as settling and evaporation lagoons. In 1984,
Lagoons 1 and 2 were excavated ant:4 also lined with concrete. Contaminated soil excavated from
beneath the lagoons was removed and disposed of in an area west of the plant area. The
saturated soil was landfarmed and then used as fill material for expanding the facility's parking
lot. A fourth lagoon was installed in 1992 as part of the treatment system to treat the
contaminated groundwater generated by the OU #1 Remedial Action (RA). In the remainder of
this Record of Decision (ROD), the term WSiteW refers to the areas investigated as part of OU #3
(Le., Area 2, the lagoon area, and the Northeast Tributary) unless otherwise specified.
Land use of the areas immediately adjacent to the NSCC property is a mixture of residential and
industrial developments. An industrial park is located on the east and south sides of the Site.
Another industrial park is located along the southern property line. A mobile home park adjoins
the extreme southwestern comer of the NSCC property. Two housing developments lay to the
north, one of which is adjacent to the facility property. The location of the nearest private, potable
wells is approximately 2,700 feet north of Area #2.
2.0 SITE HISTORY AND ENFORCEMENT ACTlVmES
In September 1968, Proctor Chemical Company purchased the 465-acre tract of land on Cedar
Springs Road. Within the next year, Proctor Chemical waS acquired by NSCC which operated
the facility as a separate subsidiary. Construction of the plant on Cedar Springs Road began in
1970. On January 1, 1983, Proctor Chemical Company was dissolved and its operations merged
with NSCC.
The primary products of this facility are textile-finishing chemicals and custom specialty chemicals.
Volatile and semi-volatile organic chemicals are used in the production process along with acidic
and alkaline solutions. Acidic and alkaline solutions are also used in the cleaning processes.
The liquid waste stream from the manufacturing processes include reactor and feed line wash and
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MME*
NATIONAL
STARCH SITE
KANNAPLOS
16 MILES
FIGURE 1
LOCATION OF THE NATIONAL STARCH &
CHEMICAL COMPANY SUPERFUND SITE
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250 7b0
GRAPHIC SCALE: I'=b00'
FIGURE 2
LOCATION OF FEATURES ASSOCIATED
WITH OPERABLE UNIT #3
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r -
NATDW. STAIOI & Ci&IcM. COIFI«'f 9.JIBIuc) SITE
~ CE DEasoN FeR 0Pswu UIrT t3
-4-
rinse solutions. This wastewater may include a combination of the following chemicals:
acrylimide, 1,2-dichloroethane (1,2-DCA), methyl isobutyl ketone, methanol, styrene, maleic
anhydride, vinyl toluene, sulphonated polystyrene, epichlorohydrin, oetyl alcohol, ethyl alcohol,
allyl alcohol, allyl chloride, sodium hydroxide, and sulfuric acid.
As the result of finding contaminants in groundwater and in the surface water/sediment of the
Northeast Tributary, the original scope of work specified in the initial 1987 Remedial
InvestigationlFeasibility Study (RI/FS) Work Plan was expanded. The first RifFS resulted in OU
#1 ROD which was issued by the Environmental Protection Agency (EPA or Agency) on
September 30, 1988. The OU #1 ROD divided the Site into two Operable Units. The ROD for
OU #1 required the installation of a groundwater interception, extraction, and treatment system
in the westem portion of the facility. The contaminants in the groundwater in this area are
emanating from the trench area. OU #2 further investigated the contaminated soils in the trench
area along with additional monitoring of the surrounding tributaries. OU ##2 ROD was signed on
September 28, 1990 and required additional work to identify, characterize I and delineate the
contamination being continuously detected in the Northeast Tributary. This investigation has
resulted in the development of OU #3 and OU #4. .
The NSCC Superfund Site was proposed for inclusion on the National Priorities Ust (NPL) in April
1985, re-proposed in June 1988, and finalized on the list in October 1989 with a Hazardous
Ranking System (HRS) score of 46 51. The HRS score was based on the following exposure
route scores: exposure via groundwater pathway - 80.46, exposure via surface water pathway-
0.00, and exposure via air pathway - 0.00. Currently, the Site is cataloged as Number 257 of the
1,249 Superfund sites across the country on the NPL.
National Starch & Chemical Company, the Potentially Responsible Party (PRP), has performed
OU #1, OU #2, and OU #3 under the direction and requirements specified in the Administrative
Order on Consent (AOC) signed by the Agency and PRP in December 1986. Since there has
only been one owner/operator of this property after being developed into an industrial complex,
no -Responsible Party Search- was performed. National Chemical Starch & Chemical Company
has been and remains the owner/operator of the facility.
A special notice letter was sent on May 30, 1986 to provide NSCC an opportunity to conduct the
first RifFS. A good faith offer was submitted and negotiations were concluded with NSCC signing
an AOC on December 1, 1986. The first RI/FS was completed on June 21, 1988 and September
8, 1998, respectively. The ROD signed on September 30, 1988, divided the Site into two
operable units. OU #1 consists of contaminated groundwater and OU ##2 consists of trench area
soils and surface water/sediment in surrounding tributaries. .
Following the signing of OU #1 ROD, the Agency sent a special notice letter to the PRP to initiate
negotiations on a Consent Decree (CD) for implementing the OU 11 Remedial Design/Remedial
Action (RD/RA). However, negotiations on the CD were not successful resulting In the Agency
issuing an Unilateral Administrative Order (UAO) directing NSCC to design and implement the RA
specified in the OU #1 ROD. The effective date of the UAO was July 27, 1989.
In support of OU #2, NSCC generated Supplemental RI and FS R&ports. These reports were
prepared in accordance to the December 1, 1986 AOC. These reports were completed in May
1990 and September 1990, respectively. The Supplemental RI reported continued detections of
contaminants in the Northeast Tributary but did not identify the source of this contamination.
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NAtDW. STAAOf . ~ CQIIf«'( ~ SITE
~ ~ DEaaoN ~ 0PswI1 UIIT t3
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Consequently, the OU #2 ROD divided the Site into a third operable unit. Following the signing
of the OU #2 ROD, the Agency sent the PRP another special notice letter in March 1991 to
initiate negotiations on a second CD. This CD governed the implementation of the RA required
by OU #2 ROD. The CD was signed in August 1991 and was entered by the Federal Court on
July 20, 1992.
On December 4, 1991, EPA Issued written notification to NSCC to conduct a third RIIFS to
determine the source, nature, and extent of contamination entering the Northeast Tributary as
required by OU #2 ROD. As with the previous RifFS efforts, OU #3 RIIFS was conducted in
accordance to the December 1, 1986 AOC. The OU #3 RI and FS reports were completed on
June 2, 1993 and June 21, 1993, respectively. NSCC will be provided an opportunity to conduct
the OU #3 RDIRA as specified in this ROD through the issuance of a third RD/RA special notice
letter.
3.0 HIGHLIGHTS OF COMMUNITY PARTICIPATION
In 1986, community relations activities for this Site were initiated in conjunction with the
development of the RifFS Work Plan. In developing the August 1986 Community Relations Plan,
the issues and concerns expressed by local citizens from the Site area were compiled and an
overview of these issues and concerns was prepared. A copy of the Community Relations Plan
was placed in the Information Repository located at the Rowan County Public Ubrary in Salisbury.
A mailing list was developed based upon people interviewed, citizens living around the Site, and
people attending Site related public meetings. The mailing list also includes local, State, and
Federal public servants and elected officials.
Several fact sheets and public meetings were held with respect to OU #1 and OU#2. The
following community relations activities were conducted by the Agency with respect to OU #3.
Two fact sheets and the Proposed Plan Fact Sheet were distributed to the public during the OU
#3 RifFS. The first fact sheet, disseminated in June 1991, provided the community a status
report of activities associated with all three (3) Operable Units. This Fact Sheet provided a brief
history of the Site, a summary of current activities at the Site, a brief overview of the Superfund
program, and a list of contacts for more information. A second Fact Sheet was distributed in June
1993. This fact sheet summarized the findings and conclusions of the au #3 RI Report which
included the Baseline Risk Assessment, and provided a revised time frame for future activities
at the Site. A flyer was also distributed in June 1993 informing the public of a change in the
Agency's personnel associated with the management of the Site.
The public was informed through the Proposed Plan Fact Sheet and an ad published on July 19,
1993 in The Salisbury Post and The Charlotte Observer newspapers of the August 3, 1993
Proposed Plan Public Meeting. The Proposed Plan Fad Sheet was mailed to the public on July
15, 1993. The basis of the information presented in the Proposed Plan was the June 21, 1993
FS document. A press release reminding the public of the upcoming public meeting was also
issued on July 30, 1993. The Proposed Plan also informed the public that the public comment
period would run from July 19, 1993 to August 17. 1993.
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FIEcaIo ~ CEa80N RII 0Pswu UIIT 13
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The goals of the Proposed Plan meeting were to review the remedial alternatives developed,
identity the Agency's preferred alternative, present the Agency's rationale for the selection of this
alternative, encourage the public to voice its own opinion with respect to the remedial alternatives
reviewed and the remedial afternative selected by the Agency, and infonn the public that the
public comment period on the Proposed Plan would conclude on August 17, 1993. The public
was also informed a 30 day extension to the public comment period could be requested and that
all comments received during the public comment period would be addressed In the
Responsiveness Summary. .
On Wednesday, August ", 1993, the Agency received a request for a 30-day extension to the
public comment period which extended the public comment period to midnight September 16,
1993. A notice was mailed on August 18, 1993 to the addressees on the mailing list informing
them of this extension. An ad was afso published in the August 24, 1993 edition of The Salisbury
Postand The Charlotte Observer newspapers informing the public that the public comment period
had been extended to September 16, 1993.
Pursuant to Section 113(k){2){B){i-v) and 117 of Comprehensive Environmental Response,
Compensation, and Liability Act of 1980 (CERCLA), all documents associated with the
development of the Proposed Plan and the selection of the remedial alternative specified in this
ROD were made available to the public in the Administrative Record located both in the
Information Repository maintained ~t the EPA Docket Room in Region IV's office and at the
Rowan County Public Library in Salisbury, North Carolina.
4.0. SCOPE AND ROLE OF OPERABLE UNIT WITHIN SITE STRATEGY
As with many Superfund sites, the problems at the NSCC Site are complex. As a result, EPA
organized the work into four operable units. These are:
OU #1 - Groundwater in westem portion of the NSCC property
OU #2 - Trench Area soils and surface water/sediments in the Northeast Tributary
OU #3 - Groundwater under Area 2, the parking lot, and the wastewater treatment lagoons
and the surface water/sediments in the Northeast Tributary
OU #4 - Contaminated soils in and around Area 2 and the wastewater treatment lagoons.
This ROD has been prepared to summarize the remedial selection process and to present the
selected remedial alternative. OU #4 will focus on the contaminated soils in Area 2 and around
the treatment lagoons.
EPA has already selected remedies for OU #1 in a ROD signed September 30,1988, and OU
12 in a ROD signed September 30, 1990 (the contaminated groundwater and contaminated soils
associated with the Trench Area, respectively). Construction on the OU 11 remedial action phase
began in August 1990. OU #2 was initiated on July 20, 1992, the filing date for the CD. OU 12
ROD specified no action for the soils in the Trench Area. long-term monitoring of the soils in the
Trench Area. and an investigation to determine the source of contamination being detected In the
Northeast Tributary.
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REa:IAD ~ DEa8cN RJI QIewu UI8T t3
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The third OU, the subject of this AOD, addresses the contaminated groundwater emanating from
Area 2 and treatment lagoon area. The potential use of this contaminated groundwater as
potable water results in an unacceptable future risk to human health as EPA's acceptable risk
range is exceeded and concentrations are greater than maximum contaminant levels (MCLs) as
established by the Safe Drinking Water Act. The purpose of this response is to prevent current
or future exposure to the contaminated groundwater. OU 13 is the third of four operable units
contemplated for this Site.
5.0 SUMMARY OF SITE CHARACTERISTICS
The NSCC OU 13 AI/FS is complete. The June 2, 1993 AI Aeport. conditionally approved by the
Agency on July 7,1993, identified the source, characterized the nature, and defined the probable
extent of the uncontrolled hazardous wastes in the soil, groundwater, and surface water/sediment
in the area addressed by this Operable Unit with the acceptance of the vertical extent of
contamination in the bedrock zone of the aquifer. The OU #3 AI Aeport included a Baseline Aisk
Assessment. The Baseline Risk Assessment defined the risk posed by the hazardous
contaminants present in the area investigated as part of au 13. The Proposed Plan Fact Sheet,
based on the June 21, 1993 au #3 FS document, provided the public a summary of the detailed
analysis of the five (5) alternatives for groundwater remediation and the two (2) remedial
alternatives for addressing the cor.tqmination detected in the surface water/sediment of the
Northeast Tributary.
The overall nature and extent of contamination associated with OU 13 is based upon analytical
results of environmental samples collected from surface and subsurface soils, the groundwater,
surface water and sediment of the Northeast Tributary, and the chemicaVphysical and
geological/hydrogeological characteristics of the area. Environmental samples were collected
over a period of time and activities. The majority of the samples collected during the au 13 RI
were screened for volatile organic compounds (VaCs) as the previous Aemediallnvestigations
conducted at the NSCC facility identified vacs as the primary contaminants at the Site. A review
of the historical use of chemicals in the manufacturing processes at the Site also supports this
appraisal. The remainder of the samples were analyzed for the entire target compound list (TCl)
and target analyte list (TAL) constituents. The TCl includes VOCs, semi-volatile organic
compounds (SVOCs), pesticides, and polychlorinated biphenyls (PCBs); the TAL includes
inorganics such as metals and cyanide.
VOCs, SVOCs, one pesticide, and numerous inorganic analytes were detected in the soils and
groundwater and two VOCs and a number of metals were detected in the surface water/sediment
samples.
Background/control samples were collected for groundwater and surface water and sediment.
No background surface or subsurface soils samples were collected for au 13. Therefore, any
organic contaminant detected in the soils that could not be attributed to cross contamination, was
presumed to be a Site related contaminant. The inorganic analytical data generated for the
upgradient sediment sample (SE-12), collected from the Northeast Tributary, was used for
comparison for surface and subsurface soils.
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NA~ STAACH I ~ COIIIMI'r !UBI=\.Ic SrTE
FexJI) aF DeOIDI FOIl 0Pswu UtIT 13
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Table 1 lists the contaminants detected in each environmental medium sampled as well as the
frequency and range of concentrations detected. As can be seen, no PCBs were detected in any
of the environmental samples collected. The pesticide detected at the Site was delta-
hexachlorocyclohexane (delta-BHC). It was detected once in the soil and once In the
groundwater at very low concentrations. Pesticides have never been manufactured at this facility.
Cyanide was detected twice in the soil and twice in the groundwater at very low concentrations.
The concentrations of both delta-BHC and cyanide are below health base clean up goals. Based
on the above information, the following contaminants or group of contaminants will not be
discussed in the following sections: PCBs, pesticides, and cyanide. The following sections
discuss the results and interpretations of the data collected and generated for each environmental
medium investigated as part of OU #3 RI.
Air samples were not collected as part of the OU #3 RVFS effort. However, the air was monitored
during the RI field work as part of the health and safety effort. Based of the information collected,
the quality of the air at and around the Site is not currently being adversely impacted by the Site.
The PRP also runs routine air sampling in the active portions of the facility as part of their
internal, corporate health and safety procedures. .
The estimated volume of groundwater impacted is approximately 131 million gallons.
5.1 SOilS
A total of 107 soil samples were collected to identify the source, characterize the contaminants
present, and delineate the extent of soil contamination. The soil samples were collected from 59
different locations. These soil samples included 11 surface soil samples (0 to 2 feet below the
surface) with the rest being collected between 2 feet below surface to either the water table
interface or auger refusal.
VOCs, SVOCs, one pesticide, and inorganics were detected in the soils. To summarize the
tabulated analytical results for all the soil samples, a total of 14 different VOCs, one (1) SVOC,
one (1) pesticide, 14 metals, and cyanide were detected. As can be seen In Table 1, the VOCs
most frequently detected and observed in the highest concentrations were acetone, 2-butanone,
chloroform, dibromochloromethane, 1,2-DCA, and toluene (listed alphabetically). A variety of
metals were also detected in the soils. Although these metals occur naturally in soil, elevated
concentrations of 7 metals were detected. The following metals were either detected In onsite
soils but not In the background soil sample (SE-12) or detected onsite at concentrations at least
two times greater than the background concentration: barium, chromium, cobalt, copper,
manganese, nickel, and vanadium.
In general, the greatest concentrations of organic contaminants were found In two (2) areas. In
the soils underneath Area 2 and north-northeast of the lagoon area. The majority of the elevated
levels of metals were detected in Area 2. Based on the information generated and collected as
part of the OU #3 RI, the following sources of contamination have been Identified. In Area 2, the
source of contamination has predominantly been the underground terra-cotta piping which was
used to transported wastewater from the production area to the lagoons as well as control and
direct surface water run-off from the plant area to the embankments of the Northeast Tributary.
Currently, NSCC is replacing these buried lines with overhead, stainless steel pipes. NSCC has
also controlled surface water runoff from Area 2 through the use of banns and sumps. The
I
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REGal) OF CEa9CII FOR 0Pawu UIIT t3
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TABLE 1 RANGE AND FREOUENCY OF DETECTION OF ORGANIC CONTAMINANTS AND
INORGANIC CONSTITUENTS FOUND IN THE ENVIRONMENTAL MEDIA SAMPLED
COMPOUND SOIL GROUNDWATER SURFACE SEDIMENT
WATER
Acetone 22-4,000 (40) 9-4,200 (15) 18.52 (3) 12-63 (7)
Bis(2-<:hloroethyl)ether 13.32 (2)
Bromodichloromethane 1.220 (7) 1
2-Butanone 3-42 (30)
Carbon Disulfide 4-8 (3)
Chloroethane 3.35 (6)
Chloroform 2.900 (17) 7-8,900 (2)
Dibromochloromethane 3.31 (5)
1,2-Dichloroethane 2-1,600,000 (42) 1-660,000 (30) 2-3,200 (7) 9-1,000 (5)
1,1.Dichloroethane 1.14 (3)
1 ,2.Dichloroethene 1.200 (4)
1 ,2-Dichloropropane 5
Ethylbenzene 9-36 (2)
Methylene Chloride 1.160 (5)
Tetrachloroethane 2 107 (4)
Toluene 1-3,100 (12) 1-120 (3)
1,1,2- Trichloroethane
Trichloroethene 1 1-17 (2) 1.5 (10)
Total Xylenes 1 2-90 (4)
Vinyl Chloride 32-190 (12) 1-120 (8)
::i..1111~:::::::.:.:.. ::::::::::.;.:81I11ifliii:. '" i::~;:~;::::li111!111.1:~:::::.'::~,~:'."."'"''''''''''''','.'."' "'' .............. ""'~::::llt"fl{I!!I!!
::~:-:::':'~:':::':-:::"
Bis(2-ethylhexyl)ph1haIalB 8
Di-Mutyl PhthaIalB 2-17 (3)
Di-n«tyl PhthaJaIB
~
Delta-Hexachlorocyclohexane 22 0.16
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NA1DW. STAACH I CHEMaL ca.., ~ Srre
REaJI) OF CEa8cN RIA 0Pewu UIIT 13
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TABLE 1 RANGE AND FREQUENCY OF DETECTION OF ORGANIC CONTAMINANTS AND
INORGANIC CONSTITUENTS FOUND IN THE ENVIRONMENTAL MEDIA SAMPLEQ
COMPOUND SOIL GROUNDWATER SURFACE SEDIMENT
WATER
Antimony 5,100-8,2000 (5) 2.30 (3) 7.6 (1)
Arsenic 530-2,900 (7) 2.4 1.1-1.9 (2)
BariIJ11 33.300-198.000 (7) 28.2-737 (8) 32.1~.2 (2) 50.3~.4 (2)
Beryllium 240-680 (7) 1.2.5 (2) 0.49-0.98 (2)
Ctvomium 10,000-97,900 (7) 12.9-59.6 (6) 35.1~.5 (2)
Cobalt 13,700-74,100 (7) 47~.4 (2) 23.6-28 (2)
Copper 46,700-161,000 (7) 12.4-23.7 (2) 48.4-90.3 (2)
Cyanide 2,500-21.900 (2) 12-16 (2)
Lead 1,300-9,400 (7) 3.3-3.9 (2) 3-15.1 (2)
Manganese 382,000-2,610,000 (7) 1.5-12.000.000 (14) 60- 134 (2) 162.1,020,000 (2)
Mercury 0.05-0.06 (2)
Nickel 4,900-22,900 (7) 23.4-39.6 (3) 10.3-11.6 (2)
Selenium 0.88
Thaltium 2,500-2.600 (2) 1-3 (2) 0.38
Vanadium 71.600-379.000 (7) 10.7-272 (1 1) 14.8-24.4 (2) 146-176 (2)
Zinc 19.700.50,000 (7) 22-6.410.000 (4) 10.3.11.4 (2) 23.9-48.5 (2)
Concentrations for water samples are reported in micrograms per I~er (J.L9!I) or in parts per billion (ppb).
Concentrations for soiVsediment samples are reported in micrograms per kilogram (J1gA
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NATIOIW. STAAQj I CI&I~ Call>Ntr ~ SIn:
REcCAD ~ DEasot RJA ():oswu lJMT t3
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benns and the grade of the paved surfaces direct the surface runoff into the sumps. The surface
water runoff collected in the sumps is then pumped through above ground pipes to the treatment
lagoons. As the underground terra-cotta pipe lines are abandoned, the ends of each section are
pressure grouted to ensure that these pipe lines will no longer act as conduits. NSCC projects
that the installation of the overhead piping arrangement and abandonment/grouting of the
underground terra-cotta pipes will be completed in December 1993. .
In the lagoon area, the source of contamination was eliminated in 1984 when the PRP lined i1s
lagoons with concrete. The contamination being detected currently in the soils and groundwater
in this area is the result of past practices and the residual contamination in the soil.
A more detailed discussion of the contaminants detected In the soils will be incorporated Into the
OU #4 ROD.
5.2 GROUNDWATER
The saprolite and bedrock zones of the aquifer have also been adversely impacted by activities
at the Site. Contaminants detected in the groundwater include VOCs, SVOCs, one pesticide,
metals, and cyanide. The pesticide, delta-SHC, was detected in one saprolite groundwater
sample (NS-42) at 0.16 micrograms per liter (1lQ1I). Cyanide was detected twice at concentrations
of 16 ~gll and 12 ~gll at locations NS-13 (a saprolite well) and NS-42, respectively. Table 1
provides a complete list of contaminants detected in the groundwater along with the frequency
of detections and the range of concentrations detected. The greatest concentrations of organic
contaminants in the groundwater were found undemeath and north of Area 2 and north of the
lagoon area. In Area 2, contamination can be found throughout the entire aquifer. In the lagoon
area, the highest concentrations detected were in the bedrock zone of the aquifer.
A total of 61 groundwater samples were collected from 52 different locations. All of the
groundwater samples were analyzed for VOCs. Only groundwater samples collected from
pennanent monitoring wells were analyzed for the full analytical analyses. To summarize the
analytical results, a total of 16 different VOCs, three (3) SVOCs, one (1) pesticide, 14 metals, and
cyanide were detected in the groundwater. VOCs detected in concentrations that exceed either
Federal MCLs or State groundwater quality standards include (listed alphabetically) acetone,
bis(2-chloroethyl)ether, bromodichloromethane, 2-butanone, chlorofonn, 1,2-dichloroethane, 1,1-
dichloroethene, 1,2-dichloroethene (cis- and trans-), 1,2-dichloropropane, ethylbenzene,
methylene chloride, tetrachloroethene, toluene, total xylenes, 1,1 ,2-trichloroethane,
trichloroethene, and vinyl chloride. The three SVOCs detected in the groundwater belong to
family of organic compounds called phthalates. Numerous metals were also detected in the
groundwater. The Inorganics that were detected at concentrations exceeding two times the
concentration found in the background groundwater samples included: arsenic, barium, beryllium,
chromium, cobalt, copper, cyanide, lead, manganese, nickel, vanadium, and zinc.
Groundwater samples from the water table were collected through a variety of methods. Thirteen
(13) samples were collected through wellpoints, five (5) groundwater samples were collected
employing a push-point water sampler, twelve (12) groundwater samples were collected from
temporary wells, and nineteen (19) groundwater samples were collected using a screen water
sampler. In addition to collecting groundwater samples from the water table, groundwater
samples were collected from the six (6) saprolite and six (6) bedrock monitortng wells that were
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NATDIAL STMalI Cl&1rA. ca.Ntr ~ SITE
ReCXJI) OF DEa80N FOR 0Pswu U8IT 83
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also Installed as part of this Investigation. The depth of the saprolite wells ranged between 13
to 80 feet. The depth of the bedrock wells ranged in depth of 39 to 135 feet. The depth to the
water table ranged from ground surface at the Northeast Tributary to approximately 33 feet below
ground surface.
The R I did not generate sufficient data to completely define the vertical extent of groundwater
contamination. It is estimated that the bedrock is fractured to approximately 200 feet below
surface. The deepest bedrock well (NS-41) installed to date in this area of the facility goes to a
depth of 135 feel The groundwater sample collected from this well showed elevated levels of
VOC contamination. Additional information to address this data gap will be collected during the
RD.
5.2.1 SAPROLITE GROUNDWATER
Figures 3 and 4 show the distribution of 1 ,2-DCA at the water table and in the saprolite zone of
the aquifer, respectively. The isopleths shown in Figure 3 are based on the data presented in
Tables 2 and 3. Figures 5 and 6 show the sampling locations and analytical results for 1,2-DCA
for the data presented in Tables 2 and 3, respectively. The isopleths presented in Figure 4 are
based on the data displayed in Table 3 and 4. Figure 4 also shows the locations of the
permanent saprolite monitoring well:. and the corresponding concentrations of 1 ,2-DCA detected
in each well.
Wellpoints, push-point, temporary wells, and screen water samplers were used to collect
groundwater samples at the water table interface. Table 2 lists the frequency of detection and
the concentrations of VOCs detected at each wellpoint. Table 3 provides the frequency of
detection and the concentrations of VOCs found in the groundwater samples collected by means
of the push-point, temporary wells, and screen water samplers. Table 4 provides the most
stringent promulgated groundwater standard, the frequency of detection, and the concentrations
of contaminants detected in the permanent wells installed to monitor groundwater quality In the
saprolite zone of the aquifer. The highest concentration and the greatest variety of VOCs were
found in monitoring well NS-42. VOCs detected in NS-42 include acetone (310 ~II), 2-butanone
(240 ~gll), 1,2-DCA (82,000 ~II), methylene chloride (160 ~gII), and toluene (220 ~II).
As can be seen In Figure 4, there are two plumes of contamination in the groundwater In the
saprolite zone. One is emanating from Area 2 and the ottier one originates in the lagoon area.
Both plumes have migrated approximately 400-500 feet from their source in a northerly direction.
The concentrations detected In the lagoon area are greater in the groundwater than in the
unsaturated soils. This Indicates that the contaminants are" being flushed out of the unsaturated
soils through the natural processes of precipitation and percolation.
Monitoring well NS-37 had the largest variety of Inorganics detected and typically the highest
concentrations of inorganic constituents as well. The metals detected In N5-37 which were twice
the background concentration were barium (737 ~II), beryllium (2.5 ~II), chromium (63.6 ~),
cobalt (66.4 ~), copper (487 ~gll), manganese (1 ,500 ~II), nickel (39.6 v.gII), vanadium (272
~gII) and zinc (220 ~II).
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NA1ICIW. $TAAOII CIeIICM. cc.Ntf ~ SITE
REcaID a: DEaSON R:JA 0PewIJ: UII1' 13
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5.2.2 BEDROCK GROUNDWATER
Figure 7 shows the distribution of 1,2-DCA in the bedrock zone of the aquifer. This flgure'also
shows the locations of the permanent bedrock monitoring wells and the corresponding
concentrations of 1 ,2-DCA detected in each well. Table 5 lists the most stringent promulgated
groundwater standards, the frequency of detection, and the concentrations of contaminants
detected in each bedrock well. The highest total concentration of volatiles and the greatest
variety of volatiles were found in monitoring well NS-40. VOCs detected in NS-40 included bis(2-
chloroethyl)ether (32 ~g/l), 1,2-DCA (99,000 ~/I), 1, 1-dichloroethene (5 ~gII), methylene chloride
(66 ~g/l), tetrachloroethene (7 ~g/l), 1,1 ,2-trichloroethane (6 ~II), total xylenes (11 ~gII), and vinyl
chloride (120 ~/I).
Monitoring well NS-38 had the largest variety of inorganics detected and typically the highest
concentrations as well. The metals detected in NS-38 which were twice the background
concentration were barium (635 ~g"), chromium (13.3 ~/I), cobalt (93.6 ~gJI), and manganese
(12,000 ~/I).
5.3 SURFACE WATER AND SEDIMENT
A total of 33 surface water and s,jiment samples have been collected from the Northeast
Tributary. The first samples were collected in March 1987 and the most recent samples were
collected in January 1993. All the samples collected were analyzed for VOCs. In addition to
being analyzed for VOCs, two of the samples (SW/SE-12 and SW/SE-13) were also analyzed for
SVOCs and metals. Sampling location SW/SE-12 is the upgradientbackground surface
water/sediment sampling location. Each sampling event has shown contamination to be present
in the surface water and sediment of this tributary. To date, only two (2) VOCs, acetone and 1,2-
DCA, have been detected in this stream. As in the other environmental media samples, metals
were also detected but these metals occur naturally. Two metals were detected at concentrations
at least two times greater than the background concentration. They are manganese in the
surface water and copper in the sediment. It was the continuous detection of 1,2-DCA in this
stream that led to the initiation of OU #3. The objective of OU 13 RI was to identify, characterize,
and delineate the source of contamination continually being detected in the Northeast tributary.
The highest concentration of contaminants was detected in the reach of the tributary that is just
east of the production facility. Table 6 lists each sampling event, the sampling locations, and the
analytical results for 1,2-DCA in the water column and sediment. Table 7 lists the analytical
results for the samples collected at sampling locations SW/SE-12 and SWISE.13. Figure 8
shows the surface water sampling locations and Figure 9 shows the sediment sampling locations.
These figures also present the analytical results for 1,2-DCA for the last samples collected at
these sampling locations. The highest concentration of 1 ,2-DCA detected in the surface water
was 3,200 ~gII in May 1992 at sampling location SW-13 and the highest concentration of 1,2-DCA
detected in the sediment was 7,400 ~g/kg in June 1991 at sampling location SE-14. Sampling
location SW/SE-13 is just downgradient SW/SE-14.
As can be seen in Figures 8 and 9, no contamination was detected upgradient of the Site (SW-
12, SW-12A, and SE-12). The concentration of contamination increases as the stream flows
adjacent to and past Area 2, the production area. The concentrations decrease as the stream
flows away from Area 2.
....----- ...--
. .-. -_u_.. -- _.-
-- - . -_._- .
-------
r-
N8S0 -
LEGEND
NO GAOI.H)NATER ~ POINT
~ SHOWING ',2.ocA~'nON
~)
, , -- . , ,2.OCA COfoICENmA 'nON
10000 -'~~' CONTOUR
NO'TC. ConftmInon 0811
~,...,..a D\';~
~on; alia
/ ;
...........::::/j
,.::::::::::........... / /
,,' ; I
' If
; I
I;
,'.;-:--"'. I !
N~ . -: >::,;".-. !
:-::::::::::::::::~~:~::::~:~~~~<':N;~ ': ;c.NO ~ II !
:. :' /'! ..'"'' I I ~XIMA'TCSCALE!ft)
I. ,I I . I I i
- ;.. 000 100 ,i i I 0 '00 - - - 100
: 5-< 1~ :::::::::::::'~"-"" ,420 r i ;
N250 -, :. :, '1,30 !: .,: ~~~. 16000 I! i
-I NO~:. "',: :3400~ .:. r i 10
-t : . ',,+.'.':'::~~' ~~D I J I~
: , ' . .' L I (f)
N;9:i::-.';-:: :::. ~. --.- - m-- - -" .:: ::.;~;:::::::.... ~~ ~:::. _:: ::::::::::: :[: ~
-[ NDo .....<2„~".. ~~D I ~
'... a::
.,/ ~-----..._:;, ' 0 NO ~
- NO ,,/ 3800 . !1ao~',:. '. W
NO A' .,,,..,. . 6 .". :. It)
_: 0 1000 ..~-"~,::'..' !
I ~ ~I:J:"1t<",,,4[~:r'.NO II
. ~----;oo
L I ~ Np I b./IjD ' I I
450 E-8 E.5O E250
ABANDONED
RAILROAD SPUR
NSSO -
CHAIN UNK FENCE
FIGURE 3
CONCENTRATIONS AND ESTIMATED
EXTENT OF 1,2-DICHLOROETHANE
CONTAMINATION IN THE GROUNDWATER
AT THE WATER TABLE
-------
....'i- ,
" ,\'-, '\
--'- J J I \ \
, ,~...~_....... " / L" .
.... "'fi . \
_Ii " ,',--, ',~' ,','.1 II I NS.13
f .-------------.--.--.:../.,, ",' -',' \ \ 1\ (1700)
, ".... , . ,/ - - \ II I
450 - : : : .......__.~~...,,-:: " - - '~' \ \\ II
I (: ,:,\ '... - - -.... \ \' I
-I r: '::\ ,'1 ..._...,'11:
I ,;: ': .~...__u_,.J...., " , II
- I ~: I: ._...../.L. \ Ns.3S II . .
I : ' ~ -,:g.. I II
! : : ; I 0:, .. S (72000) I NS043 ,
150 - I : : : ~ : : ~ i 8 ,.,",', I (NO) I ~
I :: :; 1;;1 , ' '" I I 0
I ' ' 'J, , ' . \ , ... -' ""
- , ' ",' , , , - I I J I Ct
: : \: i:' ' - ,'" r i ",
. :: : \ . ,:' - - -,."" I I V~
,........ ... -.............-- ,_.... ,.--.~.._.,. ~,",-~", C)
'--'" TNS':12 -- --.. '--"""~i":,','-;",:""o-- ~. . ;. , ; -/ . , : :::: :::::""..1 ~
-150 _1 (NO) "'"' ","'...."" :_---~ \ I' ""J1 a:Q.
I '",',--' .... \
,/,,,. '\\ tJJ
I~, . - \ I
-! /~~' :-1 ;-=r-~,: \ I~ I ~
1/, , ' ' " , W
I ..!L. N~2 .;, " ,', to
"",\Ii \' (8 ,'. "
\\ " ~-'3'" ,'/
1'\, ' ~bbol'il! (1!00) :'''~ ,
" "~:'-:. - -:.'_...."" I
- - - - -- - . ~ I
I
.
NS-37
(1J)
1050 -
..:.;:: :::..":::::::::::
750 -
ABANDONED
RAILROAD SPUR
..
~ -450 -
n
U
.750 I
-450
~
550
~~/
~r
1/
LEGEND
... 1
',2.()CA CONC:SNTRAT1ON
C
-------
NAnOtW. STARCH a Ctt:1I1CAl CoIIPAHY SUPERF\H) SITE
~ Of DECISION FOR OPEIWILE UIIT t3
-16-
FREQUENCY OF DETECTION AND CONCENTRATIONS OF ORGANIC CONTAMINANTS DETECTED IN
GROUNDWATER SAMPLES COLLECTED FROM WELLPOINTS (WATER TABLE) AND PERMANENT MONITORING
WELLS NS-13 AND NS-14
(Samples were only analyzed for VOCs)
TABLE 2
COMPOUND
FREQUENCY
OF
DETECTION
VOLATILE ORGAtfC COMPOUNDS
Acetone 10/15
Carbon Disulfide 3115
CtWroethane 3115
1,2-Dichloroelhane 7/15
1,1-Dichloroelhene 1/15
1,2-DichIoroelhene 2/15
1,2-DichIoropropane 1/15
Methytene CNortde 3115
TelradDoelhene 2115
ToUtne 3115
1,1,2-TrtchIoroethane 2115
Trtc:hIofoethene 2115
~ ChlorIde 4115
TWP.1A
(Backgroood)
TWp.2
TWP-3
TWP-4
TWp.S
TWP-6
TWp.7
TWP-8
:::!:!!::::!;I::'II'I:':;!:!!:!!::!::::~!':::::::::!:~il:::I:::::::!~!I:I:I:::::I:_::~::::::I:jj: ::::::rjl::!'J~"p:':~:!:::::,I:~:::::::lfI::~::::i:!:::: :::j:::::::'!.,'~':::::::'~,,:::::!::~:::~::j::j:~';I':~II':::::i,: 10 U
5 U 5 U 5 U ::::::I:i:i::::II::~::::!i:::::::!::::!: 5 u:::::!::;::!!:!::I::~:!:;!!!::I:::' 5 U 5 U
10 U 10 U 10 U 10 U 10 U 10 U 10 U:j',:::;I:i,;i,1:1'\:'I,II::!:!lj:!Ii,!j!,i,
,::::1j::::::::I),::I:::::::::;::::II!I:::III::II:I::;:1
5U 5U
10 UJ 5 U 5 U 5 U 5 U 5 U
5 U 5 U 5 U 5 U 5 U 5 U
5 U 5 U 5U 5U 5 U 5U
5 U 5 U 5 U 5 U 5 U 5 U
10U 5U ::1}tJ.1i}ill'II;:~!~:, 5 U 5 U 5 U
5U 5U 5 U 5 U 5U 5U
5 U 5 U ;;i!~j;il{,!ri11f~ji!i:: 5 U 5 U 5 U
5U 5U 5U 5 U 5U 5U
5U 5U 5 U 5 U 5U 5 U
10U 10U 10U 10U 10U 10U
5U
5U
.:.:.:.;.;.:-:-;.;".:.:.;.:.:.;.;.:.;.:.;.:.:.;.;.:.;.
lM:M:::j::I:j::jj:::::::::ij::
5U
5U
5U
5U
10U
10 UJ
5U
10U
5U
5U
5U
5U
-' ..
" ...
. .
.: "..
;: ,'..' ::;
.-:' ...,','.-,', :-.'
-------
NA TlOtW. Sf ARCH I CIEMICAl CoMPANY SUPERFtJI) SlT£
RECORD Of DECISION FOR 0PEAA8l£ UNIT 13
-17-
TABLE 2 FREQUENCY OF DETECTION AND CONCENTRATIONS OF ORGANIC CONTAMINANTS DETECTED IN
GROUNDWATER SAMPLES COLLECTED FROM WELLPOINTS (WATER TABLE) AND PERMANENT MONITORING
WELLS NS. 1 3 AND NS. 1 4
(Samples were only analyzed for VOCs)
COMPOUND FREQUENCY TWp.9 TWP.10 TWp.1 1 TWP.12 TWp.13 NS.13 NS.14
OF DETECTION
VOLAl1LE ORONIC COMPOUNDS
................................ :::::1::~i::i:i:!;:~:I:I::::ji:,j:::!~:::::~::: '.".".'.".".".".".".'.'.'.',','.".",'.'.".',','.'.','.'.',",','.
":::j::j:::::::::::::::I:~:1::::::::i::::i:::' ................................
................................
Acetone 10/15 10 U 10 U 10 U ~:j:::!::!:::j:!j::~:~:I::~i:j:j::j::jj:::::j::::! 10 U
Carbon Disulfide 3/15 5 U 5 U 5 U 5 U 5 U 5 UJ 5 U
~:!i:::i::::1:i!:!!I:i:i!!::i:i!:[!1:::: .~'.'.'.'.'.'.'.'.'.'.'J'.'.'.'.'.'.'.'.'.'.'.'.'.......'.".".
Chloroethane 3/15 10 U .:j:::::::;!!::::::::1,i:f~::::::::::::!::::::::::: 10 U 10 U 10 UJ 10 U
j:::~\!!jl~II::I:::II:!i -,,""'...."."-""""""" ::il:I::::li~II::I:::ii:II::' ""'h"',""',-,-"""""",,, .'.','.'.'."'.".'.".'.'.'.',",",'.',".".',".".',",'.".'.",".".'
.......................".,.........
~::;:::::;:::::::::;:;:::;:::;:~~;:::::::~~::::~::~;:~~ .:j:::t:;::I!l.g;pj:::::::!::::::::~ ::::::f~!!;:.:m::::::;:j:::::::.
1 ,2-Dlchloroethane 7/15 :N):::::::jj:gq:lwm:;jj: 10 UJ 5 U
....:.;.:-;.;.:.;.:.;.;,;.;.:.:.;-:.:.;,:-:.:.:-;.:.;.;.;.:.:.;.:
1,1-Dlchloroethene 1/15 5 U 5 U ::::::';::!:;;::i:j:::!::lll;iMI 5 U 5 U 5 UJ 5 U
1 ,2-Dlchloroethene 2/15 :i!i::ij!l~i:~I!i:I::i::!il:!~f,\1!:~ 5 U :!ii:II~:!li!:::!1I!:r!1:1!~1:!i:i:i: 5 U 5 U 5 UJ 5 U
',',',','.','.',',',',',',',','.','.','...'.',','.','.',',',
1 ,2.DIchIoropropane 1/15 1J~~j~~~!~~~~J,~~[!;,J,~1j~!~~tt~~~j!ljj~ 5 U 5 U 5 U 5 U 5 UJ 5 U
Methytene ChlorIde 3/15 10 U 10 U 10 U 10 U 10 U 5 U 5 UJ
Tenchloroelhene 2/15 5 U 5 U .:!*!!I!!:!!i:il!!:!1:!ii!ii!i!:f~!!::!1 5 U 5 U 5 UJ 5 U
TobJne 3/15 5 U ::!II!:I:;I!~i!!::~~!~!lm 5 U 5 U 5 U 5 UJ 5 U
1,1,2-Trlc:tmMJhu1e 2/15 III 5 U i;~J~i~iji~~ll;I!;ji!l~rj!!i; 5 U 5 U 5 UJ 5 U
TrId1Ioroel1ene 2/15 5 U 5 U 5 U :ill!I~11:1:;llil!Jrl\"I: 5 UJ 5 U
,.., ~;~;~iijrJ~! il!f[11Irj!;illli"ifjrjl .~lr;\lt~lfr\!';fl'JIIIJi
Vi1yt CtDIde 4115 10 U 10 U 10 UJ 10 U
~....;.:-:
Samples were collected In May 1992.
Concentrations 818 In micrograms per hBr 6aWI) or parts per bilion (ppb).
Shaded area eMma depicts positive detections.
D - Sample anaijiad at secondary dlullon.
J - Conc:enratlon Is estimated.
U - lkIdetected at the Indicated quantltatlon 8m II.
W - Undetected; the associated quantltation linll Is an estimated value.
-------
NAnorw. STMCIt & ClEIICAI. CoIFANY SUPsIAJIo Sin
~OOAD OF DEaSIOH FOR 0PE1WIlE UNIT 13
-18-
TABLE 3 FREQUENCY OF DETECTION AND CONCENTRATIONS OF VOLATILE ORGANICS DATA FOR GROUNDWATER SAMPLES
COLLECTED FROM PUSH-POINT SAMPLER, TEMPORARY MONITORING WELLS, AND SCREENED WATER SAMPLER
(Samples were only analyzed for VOCs)
COMPOUND FREQUENCY GW-18 GW-1A GW-1 B GW-~ GW-3 GW-S8 GW-SA Gw-e GW-6RE
OF DETECTION
SAMPLING DATE 11/20/92 NA 1214192 11/20/92 11/21/92 11/21/92 11/23/92 11/19/92 12116192
DEPTH TO WATER 8 NA 8 17.8 9.8 6.45 15 6 6
TABLE (feet)
VOLA11LE ORGANIC CoMPOUNDS
...,.............-,.......-.. ~:i!i::!!:!!ill[I[I;I!I~.
Acetone 4/33 25,000 U 10 U 10 UJ 250 U 10 U 10,000 UJ 10 UJ .~:i:i:=i!!i:::JI!i::II!:i~::'
.:::::::::::::;:::::::::::::::::::::::::::~::::::;:;::::::
Carbon Disulfide 1/33 12,000 U 5 U 5 U 120 U 5 U 5,000 U 5 U ,=::jj\\jIjj\\::\i;ili::;;:;;;::\::ij\' 5 U
Chloroethane 2/33 25,000 U 10 U 10 U 250 U 10 U 10,000 U 10 U 10 U 10 U
Chlorofonn 1/33 -- 5 U 120 U 5 U 5,000 U 5 U 5 U 5 U
:!~~iif.fll~lllt\:= ;!!~:ljll:::I:~~; ................-..-.............. ~:j!!!~1jiji~R;:i::ljj:~i:i:i:
1,2-Dtchloroethane 16133 5 U =:j@!;:lig:jiJ.:j!jj!ii,i 5 U 5 U
1,1-Dtchloroethene 1fJ3 12,000 U 5 U 5 U 120 U 5 U 5.000 U 5 U 5 U 5 U
1.2-Dtchloroethene 1fJ3 12,000 U 5 U S U 120 U 5 U 5,000 U 5 U 5 U 5 U
EthyI)enzene 2/33 12.000 U 5 U 5 U 120 U 5 U 5,000 U 5 U .:!!j~:i~[!!!~I!i;\ill
Methylene Chloride 3/33 12,000 U 5 U 5 U =!11;111\lliillll::111\11 5 U :~!:li~ll-:li.i:!li!~!\ 5 U 5 U 5 U
Tetrachloroelhene 2/33 12.000 U 5 U 5 U 120 U 5 U 5,000 U 5 U 5 U 5 U
Toluene 3/33 12,000 U 5 U 5 U 120 U =!::!li!l!fj!i=:!I:~llill 5,000 U 5 U 5 U 5 U
;::~::::;~::$'
Total Xylenes 3/33 12.000 U 5 U 5 U 120 U 5 U 5.000 U 5 U :~:;if'
:::~:~~:"
1,1 ,2- Trichloroethane 4133 12,000 U 5 U 5 U 120 U 5 U 5,000 U 5 U S U 5 U
Trlchloroethene 1/33 12.000 U 5 U 5 U 120 U 5 U 5,000 U 5 U 5 U 5 U
Vinyl Chloride 2/33 25.000 U 10 U 10 U 250 U 10.000 U 10 U 10 U 10 U 10 U
.
-------
NAnONAl STARCH & CIEMICAl COMPANY bBIFIIID SITE
A:CORD Of DEasIoN FOR OI'EIWU UNIT 13
-19-
TABLE 3 FREQUENCY OF DETECTION AND CONCENTRATIONS OF VOLATILE ORGANICS DATA FOR GROUNDWATER SAMPLES
COLLECTED FROM PUSH-POINT SAMPLER, TEMPORARY MONITORING WELLS, AND SCREENED WATER SAMPLER
(Samples were only analyzed for VOCs) (continued)
COMPOUND GW.7 GW.7A GW-8 GW-8D GW-88 GW-11A8 GW-11 8 GW.12 GW.12A
SAMPLING DATE 11/23/92 11/24192 12/4/92 12/5/92 12/5/92 11/24/92 12/3/92 12/6192 12/2192
DEPTH TO WATER 9 25 1 1 5 6.5 12.5 16 17
TABLE (feet)
VOlA11LE ORGANIC CoMPOUNDS
Acetone 10 UJ 10 UJ 10 R 10 R 10 UJ 5,000 UJ 10 R 10 UJ 10 R
Carbon Disulfide 5 U 5 U 5 U 5 U 5 U 2,500 UJ 5 U 5 U 5 U
..........................--..-..
Chloroethane ::!iili:i.~~!lliii:i!ii:ii. 10 U 10 U 10 U 10 U 5,000 UJ 10 U 10 U 10 U
Chloroform 5 U 5 U 5 U 5 U 5 U 2,500 U 5 U 5 U 5 U
1,2-Dlchloroethane .--- 5 U 5 u .i::jl:jlllaig::iii!: 5 U ::::jj:i:i:I::i::::1.:!:.1.:!~J.I~I: 5 U
1,1-Dlchloroethene :: 5U 5U 5 U 5 U 2,500 U 2,500 U 5 U 5 U
1,2-Dlchloroethene 5U 5U 5 U 5 U 2,500 U 5 U 5 U 5 U
»:..
Ethybeozene 5 U 5 U 5 U 5 U 5 U 2,500 U 5 U 5 U 5U
Methytene Chloride - 5 U 5 U 5 U 5 U 5 U :[!:1.il!I~'II:ll:ilil.ifi:~!: 5 U 5 U 5 U
Tetrachloroethene 5 U 5 U 5 U 5 U 5 U 2,500 U 5 U 5 U 5 U
~
Toluene 5U ...... 5 U 5 U 5 U 2,500 U 5 U 5 U 5 U
. .
Total Xytenes . 5U 5 U 5 U 5 U 2,500 U 5 U 5 U 5 U
1,1,2- Trtchloroethane 5 U 5 U 5 U 5 U 5 U 2,500 U 5 U 5 U 5 U
Trichloroethane 5 U 5 U 5 U 5 U 5 U 2,500 U 5 U 5 U 5 U
Vinyl Chlortde 10U 10 U 10 U 10 U 10 U 5,000 U 10 U 10 U 10 U
.
-------
---------- ---- -------
. .
NAtiONAl STARCH & CIEIIICAl CoIIPANY SUPslFIIIO SITE
"'CORD OF DECISION FOR OPERAIIlE UNIT 13
-20-
TABLE 3 FREQUENCY OF DETECTION AND CONCENTRATIONS OF VOLATILE ORGANICS DATA FOR GROUNDWATER SAMPLES
COLLECTED FROM PUSH-POINT SAMPLER, TEMPORARY MONITORING WELLS, AND SCREENED WATER SAMPLER
(Samples were only analyzed for VOCs) (continued)
COMPOUND GW.13 GW.14 GW.15 GW.16A GW.17 GW.18 GW.18A GW.19
SAMPLING DATE 11/20/92 11/21/92 12/17/92 12/2192 12/1/92 11/23/92 12/18/92 NA
DEPTH TO WATER TABLE (feet) 4.5 4.5 3 10 4 7.5 7 NA
VOlATILE ORGANIC CoMPOUNDS
Acetone 10 UJ 10 U 180 UJ 10 R 10 R 10 UJ .:::.:::.:":::::::!::::II::;Ji::i:::!::!:I:, 10 U
Carbon Disulfide 5 U 5 U 5 U 5 U 5 U 5 U 17 U 5 U
Chloroethane 10 U 10 U ~::::::'::::::i::::::!:i!:::I::li::::::::::i::!:!::!:i:il: 110 U 10 U 10 U 33 U 10 U
Chlorofonn 5 U 5 U 5 U 5 U 5 U 5 U 17 U 5 U
....... ... ......... .... ..................".".".. :::1-
.. ............... ......... ..................................
........ ..... .............. ..................................
1,2-Dichloroethane 5 U 5 U :~':~::.::.1.6.QOO. b\:::,,::: 5 U ..:::::'::~:::',~~::g::::::i::::::: 5 U 17 U
1,1-Dichloroethene 5 U 5 U 5 U 5 U 5 U 5 U 17 U 5 U
1,2-Dlchloroethene 5 U 5 U 5 U 5 U 5 U 5 U 17 U 5 U
Ethybenzene 5 U 5 U 5 U 5 U 5 U 5 U 17 U 5 U
Methylene Chloride 5 U 5 U 11 U 5 U 5 U 5 U 17 U 5 U
Tetrachloroethene 5 U 5 U !:!:!ii~i:~i:!~\":i:I:!!fJ.!:*:i:~:!!: 5 U 5 U 5 U 17 U 5 U
Toluene 5 U 5 U 5 U 5 U 5 U 5 U 17 U 5 U
Total Xylenes 5 U 5 U 5 U 5 U 5 U 5 U 17 U 5 U
1.1,2- Trichloroethane 5 U 5 U r- 5 U ::.i~;I:i.!!~!~I: 5 U 17 U 5 U
I
Trlchloroethene 5 U 5 U 5 U 5 U 5 U 5 U 17 U 5 U
Vinyl Chlortde 10 U 10 U ::iiillfii::!::i:i:i:II.!:::!:::iillilii:ilil 10 U 10 U 10 U 33 U" 10 U
-------
NATIONAl STARCH a CIEIIICAI. ~AItt SUPEAfuI) SITE
RECORD Of D£asIoN FOR OP£fWU UtlT 13
-21-
TABLE 3 FREQUENCY OF DETECTION AND CONCENTRATIONS OF VOLATILE ORGANICS DATA FOR GROUNDWATER SAMPLES
COLLECTED FROM PUSH-POINT SAMPLER, TEMPORARY MONITORING WELLS, AND SCREENED WATER SAMPLER
(Samples were only analyzed for VQCs) (continued)
COMPOUND GW.22 GW.24 GW.25 GW.26 GW.27 NS-13 NS-14
SAMPLING DATE 12/18/92 12/18/92 12/19/92 1/23/93 1/24/93 11/24/92 11/24192
DEPTH TO WATER TABLE (feet) 7 16 11.5 14 19 5.44 5.2
VOlAnLE ORGANIC CoMPOUNDS
Acetone 10 U !~rJr:!j!;!jijr~!!r:!~lBil!jij!!i~ijr:r~iii1i!ij; 10 U 20U 21 U 14 U 12 UJ
Carbon Disulide 5 U 5 U 5 U 5 U 5U 5 U 5 U
Chloroethane 10 U 10 U 10 U 10 U 10 U 10 UJ 10 UJ
Chlorofonn 5 U 5 U 5 U 5 U 5U 5 U 5 UJ
1,2-Dlchloroethane 5 U 5 U 5 U 5 U 5 U :::i;:;:i!:iii::::::i~:~IQQ:::g!,!;~~!!:i:!~ 5 UJ
1,1-Dlchloroethene 5 U 5 U 5 U 5 U 5U 5 U 5 UJ
1.2-Dlchloroethene 5 U 5 U 5 U 5 U 5U 5 U 5U
Ethylbenzene 5U 5U 5 U 5U 5 U 5 U 5 UJ
Methylene Chlortde 5 U 5 U 5 U 16U 15 U 5U 5 UJ
Tetrachloroethene 5U 5 U 5 U 5 U 5U 5U 5 UJ
Toluene 5 U 5 U 5 U 5U 5 U 5 U 5 UJ
Total Xylenes 5 U 5U 5 U 5 U SU 5 U 5W
1,1,2. Trtchloroethane 5U SU 5 U 5U. 5U .;::j::j;;!ii~:\!!iiil!t. SW
..
Trlchloroethene SU 5 U 5 U 5U ~illifi!!!fi!!iii:i('-- SU 5 U
Vlnyt Chloride 10 U 10 U 10 U 10U 10 U 10 U 10W
Concentrations are In rnlcrc9ams per Alar (J101) or pW per billion (ppb). Shaded area ('Eli) depicts positive detections.
. . Detection limits for YOCs are elevated; presaeenlng of san1Jle Indcated matrix effects required medum or high level analysis.
D . Concentration reported from secondary dilution. J . Concentration Is estimated. NA . Not Available R . Unusable results.
RE . Resampled. U . Undetected at the Indicated quantitation limit. UJ . Undetected; the associated quantitation limit us an estimated value.
-------
111150 -
IIISSO -,
I
-'
I
I
-l
III 250 -1
I
i
CHAIN UNK FENCE
i
~
iTWp-13:
i (2400J) !
! :
E
//1
~ .' .:::::::::::::::::::::::/ / i
~~ ..-::.., 'i ! /1
.~,. ~ /111
... ~ ' y
16$ :,' Ii
, .
......... ......-[[[
: :.........---.---.-; ;--..--: I
' . , ' .
,
ABANDONED
RAILROAD SPUR
~l/
,
If
-""""'OXIMA ~ SCALE (1'1)
, '
o
ICIO
'00
- ICIO -
, '
, ' : : : ---'----------'TWP.'1
: : ::; ::'-'~~~-~--- :(:' ~=O I
" ' TWP" I
~ : ~ : :: : ' (4eooJJ I
-\ :: ..u....... : : :' : TWP.9 ,
.__......J...._.._-~ :__: ;........__. ' : :__....._--_......._--.,.'.(.6100J) ...(3200) ....._-J
~.so. - ". -....... --"'" -- - - -. - -.- --""""'-
j P~LOT-- ;:::::: ~)7-~-~:~--""T1
-II!! :--'-'''~.5 ~ (NO) [,I LEGEND
NS-13 (NO) TWP~
~ ~-, (900) --\ (NO)
i~.li~II~I1WP.~iOTWP~ I iO=
,SA J I .. ,I (NO) (NO) e 1
~ ' I I I I I ~! I I . NS-14
E 450 lAJ / e 250 t (NO)
~MPORARY WEU.. PONT
ANO 1.2.ocA
CONCe~TION (pCb)
MON1'T'CRNG WEU..
LOCATION AND 1.2.ocA
~TION (pCb)
FIGURE 5
SAMPLING LOCATIONS FOR
GROUNDWATER (WATER TABLE)
VIA WELLPOINTS AND
-------
~1I
It
1 NO~, ~ CI818
~ II4ICI8ft* '* Dr ~
~~o~~,:",,,,,,,,,,,,,,,:t ---
%f: ~~8AOGW.'. 1/
: 6 ~~ I
" ! I
. . GW.17- I
6 (48~) 6 r:;)16Atlll
GW.7 GW-6 APPAOXIMA~5CALE tft)
-- - _(~:)m. ~~.D) ~~ici)6 ~ ! 0 '00 aoo - - 100
GW.SA: :"'u,,-"'" i i \
(30) ~ GW.56 GW.15 I .
:: (98000) (16000) ! !
GW-4A .: :GW-46 I
(ND) t, ~(~OO) . ~
: :: : : 6 GW.14 !! a::
: :...--. ._..m......; ~..- ..._..~~~)_-....I :, ~
--.O' -~.... ......... ' \,i,I
....-........-.---..--..----..----...-.......- ,-h_. -.-.-..-..--.-- Z
I GW.12A GW.;2"-- : GW-3 1 I
r (ND) 6 (200) e:. : ~ ~ND) I CI)
\ '/ GW.13 a::
GW:25 GW.11e GW.11 .m..._t,' GW.2 6 (ND) ~
--...... (ND) 6 (ND) 6 G~~~go) 6 (5100) tJ
: GW.11A 6 (24) 6 , e:. I N5-13
rw~.1 ,Wi I) II GW.1 }'-. I (1300)
(~ 6 (660000)1 ~/~G(~Df \W'1A
I NS-14 (59)
(4J)
G~46 ~~cf.6 FIGURE 6
SAMPLING LOCATIONS FOR GROUNDWATER
(SAPROLITE ZONE) VIA PUSH-POINT
SAMPLER, TEMPORARY MONITORING WELL,
AND SCREENED WATER SAMPLER AND
CORRESPONDING CONCENTRATIONS OF
1 ,2-DICHLOROETHANE DETECTED AT
EACH SAMPLING LOCATION
LEGEND
6 OAOI.HJWAT1:R x.. S ...
GW.16 PONT'Nm41.2~
(420) CONCEN'TAATo.. (!filICIC)
NISO -
ABANDONED
RAILROAD SPUR
GW.27
(NO) 6
N550 -
GW.7A
. -. _0 - 0..0.", --- h t~~~).~
. ,
: ~_.....__..-................_.. .."'''''--. :
N250 -
/~
!l~
.'.J'~I
~//
" I
'''III. .'-
.~
. .
N-35O -
-t5O -
~
CHAIN UNK FENCE ---.l
.' .,. ".'
- . .... .. ...-
_._.-..- .
-------
NAnOtW. 5TNICH & CIEIICAl CowAHY ~ SITE i
~COAD OF D£asIoN F()A OI'EI\MU: UIIT 13
-24-
TABLE 4 FREQUENCY OF DETECTION, CONTAMINANTS DETECTED, AND MOST STRINGENT PROMULGATED
STANDARDS FOR CONTAMINANTS DETECTED IN THE SAPROLITE ZONE OF THE AQUIFER
COMPOUND PROMULGATED FREQUENCY NS-131 NS-141 NS-33 N5-35 N5-371 NS-39 N5-421 NS-U1
GROUNDWATER OF DETECTION (Becqrauncl)
STANDARDS
VOLAT1LE ORGANIC CoMPOUNDS
Acetone -- 1/8 14 U 12 UJ 10 U 10 U 10 U 10 UJ '::;::!i~:::B1111:~ffii: 10 U
Bromodichloromethane 100 2/8 5 U 5 UJ 5 U 5 U 5 U :jj:i:::,:i::.:ii::1:"~ii:jil::i::::I:' i:'il:ij:llj::Ii:~jil[!i 5 U
2-Butanone -- 1/8 10 U 10 UJ 10 U 10 U 10 U 10 U ::::::::::::!:ijgl:~'miiiir;:!:: 10 U
Chloroethane -- 1/8 10 UJ 10 UJ 10 U !!j!:!i:!1:ii!I::~:::::!!i:::~:::' 10 U 10 U 800 UJ 10 U
Chloroform 0.19 1/8 5 U 5 UJ 5 U 5 U 5 U :::i:;:ii:i:i:::i:,,~::::!:i::::!::;' 400 UJ 5 U
1,2-Dlchloroethane 0.38 5/8 .:::;iii~~:~a::I~:ji!j:. 5 UJ 5 U ii:i::iilla:ll:j:!. :::jij:::!!i:j:il.::lji!:j:i~ijj:! i:j::::III:,I::!::. ii:::j:li9m':11i~: 5 U
1,2-Dlchloroethene 70 (cisnrans) 1/8 5 U 5 UJ 5 U ;i:!f1~;m!!1!ljil!~iJ.!:; 5 U 5 U 400 UJ 5 U
Methylene Chloride 5 1/8 5 U 5 UJ 5 U 5 U 5 U 6 U ':::!:*!!i!II:I:!i~~' 5 U
T etrachloroethene 5 118 5 U 5 UJ 5 U 5 U 5 U 5 U 400 UJ 5 U
...................
Toluene 1,000 1/8 5 U 5 UJ 5 U 5 U 5 U 5 U ::i:i~11(.C.:..}{i 5 U
Total Xylenes 400 118 5 U 5 UJ 5 U 5 U ::!!\i1~!~iI14!!;li;i!: 5 U 400 UJ 5 U
1,1,2- Trichloroethane 5 318 :i:f~I~!i!!II!.~11!i1; 5 UJ 5 U :!:fi.;11{;1ill:itfi~i:: 5 U j::!}:::!:!j!!j::il:::j:~~ij!:: 400 W 5 U
VInyl Chloride 0.015 118 10 U 10 W 10 U 10 U 10 U ::I~J~~j!lll;!11Ij:i:!:: 800 W 10 U
SEll-VOLAT1LE ORCWIC COIIIoutmS
Df-n-butyl Phthalate 118 10 U 10 U 10 U 10 U 10 U 10 U ::r.I~' :~:.~ 10 U
--
PEsTIcIDES
Delta-SHC 0.05 U U 0.05 U 0.05 U :<':'~1~r:M"'.
- 1/8 0.05 0.05 U 0.05 u \~l!~Ulll:.: w' 0.05 U
-------
I-~-.
I
I :
I
NAoorw.. STARCH a CIEIICAl CoIIPAHY StI>EAF\N) SnE
R:CORO Of DEaSION FOIl ClPEIWU lHT 13
-25-
TABLE 4 FREQUENCY OF DETECTION, CONTAMINANTS DETECTED, AND MOST STRINGENT PROMULGATED
STANDARDS FOR CONTAMINANTS DETECTED IN THE SAPROLITE ZONE OF THE AQUIFER
COMPOUND
PROMULGATED FREQUENCY
GROUNDWATER OF DETECTION
STANDARDS
INORGANICS
Arsenic 50 1/8
Barium 200 8/8
Beryllium 4 218
Chromium 50 6/8
Cabab -- 2/8
Cyanide 154 2/8
LelK:t 1SO 1/8
Manganese 50 8/8
Nickel 100 3/8
Vanadum -- 7/8
ZInc 5,000 218
NS-138
NS.148
NS-378
NS-33
(8Ickgraund)
NS-35
Ns-428
NS-39
Ns-438
2 U 2 UJ 2 U 2 U 2 U 2 U ;i::i::i~:i1::i~ljji~fl~~1 2 U
i1iijil::1i!:11,Iil:ji:!!:i,i!:iii ii:!ii:::il~:li:y,i'::!:ii:i':iii::!i:::jlg:~;::::i!:::::,ii::!i:i:i'gl,':;~.::::::'::::: ::::i1!i::i!:!!:mi:!i:!i~!: .::i!l:i::Zll::y,i:'::::!:: ::::i:i:iiiii:i!I~I~lii:II!f,; "'~:'::J?WI~:
1 U i:ii:::i!!i::i!l:i:~i:::!il:!!: 1 U 1 U ::!!::ji::II:i~::I~l.\::: 1 U 1 U 1 U
:i:-: ~~ 1!iI~ : :i:'!
2 U3.3i/(' 2 U 2 UJ 4.1 U 2 U 2 U 2 U
:;~;;i~~
Concentrations are In micrograms per liter (JIOII) or parts per billion (ppb).
Shaded area (@@@U depicts positive detections.
8 - Detectlori"iimits for VOCs are elevated, due to matrix effects and analyzed under medium or high level.
b - Action Level (EPA, Region IV Established Action Level).
D - Concentration reported from secondary dilution.
J - Concentration Is estimated.
NA - Not analyzed.
U - Undetected at the Indicated quantltatlon limit.
UJ - Undetected; the associated quantltatlon limit Is an estimated value.
-------
'I' - - - 10, \
/ "," - , \
:-::::_-:::::::::::-.-::-.-_~-/ ,/.. - - - - 100.... '- \
: : : / I " , - - - - '000 ',\ \
. , :./ / " .." -. 70........ \ \ ,
"/I / ~',
- I ~./ 1 / \ \ I
. . . /._n__J.n--'-~S-36 \ \ \
I .: r"__!--L.----_. I" , .
_i :: III', ,t11000) "I''''''H
i :. r.,,' \ . '\'t~
I:: :: ~It I ",,': / ',', (ND) 0
150 - I : : ~ I ~ , , .;. ~ - .. - / /' / 0<
I : : : : I,:, I . ,,' /
.:: ;: 1,\,,, .." '// c:t
-I., ': I.,'" '--'/ 0
* ~: ;: :J:\~ --":: ;1",'11 I (!)
-~-~-::+I' ...:.: ::.::::.:.:::::.:~~~i 2~~~ ,,: (?f. ::: ::::::: :::::'1'; i
/ /t :---n.--c. , ' ~
- I / f I, ,. 80000 I \ I I , -
I /1'" . 1 'I 0
.! I II, I NS-40 I I I I I I W
.1,\ \ 99000) I I,.' 0
I " \, \ ( T . N~ 1 '
11 r:JG ~GOON; (39000):
U 11 '~"'... ~--~--, " I
...... :oc;.. I ." I~ '
~"":""----:_"'--..." /'
..... - --
~ - ----
1050 -
750 -
-i
i
~-!
,
i
,
,
I
~~50-
-750 I
.eo
.
Ns.38
(1J)
.
NS-24
(Not Sampled)
. -;<. .;;::::::::::::::::::::
ABANDONED
RAILROAD SPUR
8: "
---- S
.." ..
250
NS-34
. (ND)
I I
550
I
, .
I~GEND
t""1
.
. Ns:36
I (11000)
r,
~~/
, .
ff
1.2.()CA ~T1ON
~OUR(I:ICIb)
U.()CA CONCENTP.AT1ON
(pCIC). GROUNDWATER
SAMPLES
APPROXIMATE SCALE (II)
-
- -
-
-
FIGURE 7
CONCENTRATIONS AND
ESTIMATED EXTENT OF
1,2-DICHLOROETHANE
CONTAMINATION IN THE
BEDROCK ZONE OF THE
AQUIFER
....,..", .'
-------
NAnONAl. STARCH & CIEIICAl CoUPANY SUPsIF\H) Sift
RECORD Of DEaSIOH FOR QlEIWIlE UIIT 83
-27-
TABLE 5 FREaUENCY OF DETECTION, CONCENTRATIONS DETECTED, AND MOST STRINGENT PROMULGATED
GROUNDWATER STANDARDS FOR CONTAMINANTS DETECTED IN THE BEDROCK ZONE OF THE AaUIFER
COMPOUND PROMULGATED FREQUENCY N5-34 N5-36 Ns.381 Ns.40 N5-41 N5-441
GROUNDWATER OF
STANDARDS DETECTION (Background)
VOLAl1LE ORGANC COMPOUNDS
".............h_............. ....Uhh...................
"'"''''''''''''''''''''''''
Acetone --- 2/6 ::!::::::~~::::~:g::I:::::!!:~:::::: ::::!::::~::::::::@~.:~::::.:::::i:::!:: 10 U 10 U 1 ,200 UD 10 U
............................ :!ii!!ill:i!:::~I.::i,!:I.i~!~: ::!i!i:i!!:!:i:!.i:::I.!:II:i::::i!:!!~::!I::i!.
Bis(2-chlor09thyl)ether --. 3/6 10 U 10 U ::i:li:!:ii:::i:g.:g::::i1!!:ill:!:: 10 U
.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'~.'.'.".".
Chloroform 0.19 1/6 5 U ..::ii::::ii::::::::lg..I::::::::::::::i:::':. 5 U 65 U 1 ,200 UD 5 U
. .. .. ...........--,.............
.."....,...........-........- ::::!.:~:::::.II:.~ii::II:.!i~I!!:::ii :1:!:!:.!.1~9I::gl:!:!:!I:
..,..,........................
1 ,2.Dichloroethane 0.38 4/6 5 U ::.::i..1.1~g:::~::::::; '::::::9.Q:OOd'o.:::'~ 5 U
::::::: ;.. .'::' :::;:;
::;:t:.,::.:.+.::::..::....::,:\.::,:/":
1 , 1.Dichloroethene 7 1/6 5 U 5 U 5 U li::II:t~!::I.!I::!:;j!!i!ii~:il' 1 ,200 UD 5 U
..,..........'............... 1:!:~!!i::I:[II::lg;:.!.::I:I!::
Methylene Chloride 5 216 5 U 5 U 5 U :::::r!:f,!::!~I:~IIIII:i!l: 5 U
Tetrachloroethene 5 1/6 5 U 5 U 5 U .::::r~ll~tlll:r;!.::::!~.:i; 1 ,200 UD 5 U
Toluene 1 ,000 1/6 5 U 5 U . 5 U 1 ,200 UD 5 U
........................
Total Xylenes 400 2/6 5 U 5 U :'!~i~~:~i~jl:l:ili~:I:I!~rl 1 ,200 UD 5 U
1 ,1,2- Trichloroethane 5 2/6 5 U .i:/:i!i!IIII:I::ljill~II!1!111 5 U ::llilfl;llli::lil:ili::I/:. 1 ,200 UD 5 U
}:!:~:::tHi:::a;tmm::: ............................
Trichloroethene 2.8 2/6 5 U 5 U :!I!~!II~!:I::I!::li!I\~:illfi.: 1 ,200 UD 5 U
~i~n~~~~?~~r:::?;::::f~f~~i~fr
Vinyt Chloride 0.015 2/6 10 U :!:i:l!i:1il!II!II:li!:;1!i!lil!:: 10 u ~!:Il:!1;1Ii:II~lllil:I!: 2,500 UD 10 U
SEll-VOLAl1LE ORGANIC COIIPOua
Bis(2-ethythexyl)phthalate 6 1/6 10 U 10 U 10 U 10 U i:II1:I!:I.IIIII::I,:U.:"Jlilti 10 U
Di.n-butyl Phthalate -- 1/6 10 U 10 U 10 U 10 U :!i!~i~r~~I!~:.IJIIII~ 10 U
Di-n-octyl Phthalate - 1/6 10 U 10 U 10 U 10 U .:I&lllIl,lllil;I~J.itll 10 U
-------
NA11OIW. STARCH a CII:IIICAl CoIIPAHY SUPBIF\N) SITE
A:CORD OF OEaSlON FOA 0I'fRABU: UNIT 13
-28-
TABLE 5 FREaUENCY OF DETECTION, CONCENTRATIONS DETECTED, AND MOST STRINGENT PROMULGATE D
GROUNDWATER STANDARDS FOR CONTAMINANTS DETECTED IN THE BEDROCK ZONE OF THE AaUIFER
COMPOUND PROMULGATED FREQUENCY N5-34 N5-36 N5-388 N5-40 Ns.41 NS-448
GROUNDWATER OF
STANDARDS DETECTION (Slckgroood)
INORGANICS
Barium 200 5/6 :"!I:::IIIII;I"II!:I:~II::1 :::::::I:;:1:1::~;61:1:~";I::~)::~: ::i:::::::i:)I::[@I"!I~I~:!!::!:':11 :""::::I:!:I!:""~I:,I:::::::::::I!:~ 27.9 U !i:i'ijl::[II::I:II:':::!!:~:
':':':':':':'::':';':':':':':';';':':-:';';-:';<:-;';'. !":":I:::I:"'::::::::1~1'::I:'I:!~::::II:::: ::::::!:::::I:!:gl[ill:IIIIJ1::!i
Chromium 50 3/6 1 0 U 1 0 U .:'::::::::::::::::~:~J,~!:::::)i::::::::. 1 0 U
Cobalt --- 1 /6 20 U 20 U :I!:::::):":::;~~";I-:-i:!i::":::~ 20 U 20 U 20 U
Copper 1 ,000 2/6 1 0 U 1 0 U 1 0 U -:i!!::I:!ID:lliil::i:::;::: ":;;:::;i::::;::I~I~Y:::::::lt::::::" 1 4.3 U
Lead 1 ~ 1 /6 2 U "ii::::I:i:;::;,::-lil'lili:l:il:illi 2 UJ 2 U 2 U 2 U
...........-.......""""" "i:!i!!::~;!:HI~i!iij!I::::!: "1:!ri:::lliD::~:!i: ~:::ifi]i!:II:i1!!I:!: ==M=
Manganese 50 6/6 .
Vanadium --- 4/6 1 0 U 1 0 U "!:!ll!;Jg~I;I:::11
Zinc 5,000 2/6 :111~illll:i:illl 33.7 U 1 4 U 130 U 33 U
Concentrations are in micrograms per liter (Jigll) or parts per billion (ppb).
Shaded area O:::=:::=::ID depicts positive detections.
. - Detection'"jjmits for VOCS are elevated, due to matrix effects and analyzed under medium or high level.
b - Action Level (EPA, Region IV Established Action Level).
o - Concentration reported trom secondary dilution.
J - Concentration Is estimated.
U - Undetected at the indicated quantitation limit.
W - Undetected; the associated quantitation limit is an estimated value.
\ ;
-------
NAnOlW. STARCH & CI£IIICAI. CoMPANY 5uPEAAJIo SiTE
~ Of' DEasIoH FOR 0PE1WIlE UtIT 13
-29-
TABLE 6 SUMMARY OF DETECTABLE CONCENTRATIONS OF 1,2-DICHLOROETHANE IN SURFACE
WATER, SEDIMENT, AND SOIL SAMPLING OF THE NORTHEAST TRIBUTARY
Sample Number- March 1987 June 1987 Oct., Nov. 1989 July 1990 June 1991 May 1992 June 1992 January 1993
SW/Se-Q1 1,400/18b -- -- -- -- -- -- --
NS-W11S1 - NDIND -- --- -- -- -- --
NS-W2IS2 -- ~ NDIND -- -- -- -- -- --
NS-W31S3 -. NDINO -- -- -- -- -- --
NS-W41S4 -- 4,400 J/3,400 J -- -- -- -- -- --
SW/SE-Q9 -. -- 350/76 160/980 77/23 150 JI9 J -- --
SW/SE-10 -- -- 1,200/14 1,6ooIND 810/310 1,300 J/610 D -- --
SW/SE-11 -- -- NDINO NDIND NDIND NDIND -- --
SW-12A -- -- -- -- -- -- NO -
(Background)
SW/SE-12 - -- -- NSINO NSIND 2 JINO -- NOINO
(Background) -
SW/SE-13 -- -- -- 88013,400 1,800/7,400 3,200 D/290 -- 200 J/1,2OO 0
SWISE-14 - -- -- 1,700/1,200 1,200/4,200 590 0/1,000 D -- --
SW/SE-15 - -- -- NDIND NOIND -- -- -
SW/SE-16 - -- -- -- -- 1,300 OJ/61 -- -
S~1 -- -- -- ND -- -- -- --
So-02 -- -- -- ND -- -- -- -
-------
NAnONAI. STARCH & CIEIIICAI. CoIIPAHY SUI>EAFuIo Sin:
fBoAo OF DEcIsIoN fOR 0PE1WIlE UIIT 83
-30-
TABLE 6 SUMMARY OF DETECTABLE CONCENTRATIONS OF 1,2-DICHLOROETHANE IN SURFACE
WATER, SEDIMENT, AND SOIL SAMPLING OF THE NORTHEAST TRIBUTARY
Sample Number- March 1987 June 1987 Oct., Nay. 1989 July 1990 June 1991 May 1992 June 1992 January 1993
So-03 -- -- -- NO -- -- -- --
So-04 - -- -- NO -- -- -- --
SO-OS -- -- -- 650 -- --- -- --
SQ-06 -- -- -- 57 -- -- -- --
So-07 -- -- -- NO -- -- -- --
Concentration for surface water samples are In micrograms per liter (~gll) or parts per billion (ppb)
Concentration for sediment samples are In micrograms per kilogram (~g/kg) or parts per billion (ppb)
. SW/SE: surface water/sediment; NS-W/S: water/sediment (EPA samples); SO: soil
b First value represents concentration of 1,2-0CA in surface water/Second value represents concentration of 1,2-0CA In sediment
o - Concentration reported from secondary dilution
J - Concentration 15 estimated
NO - Analyzed for but not detected
NS - Not sampled (no water available)
U - Undetected at the Indicated quantltatlon limit
-------
-31-
NAT1OIW. STNICII & CiBIIr:AL CaJII"" ~ SITE
ReaR) ~ 0Ea8:II RIA QIewu UtrT 83
TABLE 7 CONCENTRATIONS OF ORGANICS AND INORGANICS IN SURFACE WATER
AND SEDIMENT FROM LOCATIONS SW/SE-12 AND SW/SE-13
COMPOUND/ANAL YTE
SW-12
(Background)
SW-13
ORGANICS
Acetone
SE-12
(Background)
SE-13
10 U
10 U
5U
:::::~:!:'I~!I:II!:I:II~11
~::i:;]~II~~~!I!:~1:llj1!i'~IIII~:II:i[~!liIlIIIJ1111~1I :fT. '."~:::':':'.:"::::::~:ltll~11
30 U 30 U
2U 2U
:i:::::::::;:::i:!II!~!!:~I:'::!I'i:i::i!!':i!' :::I'i::il!'!il~'!lill!::1~1UIIlII~I!~::':~:::
1 U 1 U
10 U 10 U
20 U 20 U
10 U 10 U
2U 2U
1 ,2-Dichloroethane
INORGANICS
Antimony
Arsenic
Barium
Beryllium
Chromium
Cobalt
Copper
Lead
Manganese
Mercury
Nickel
Selenium
0.2 U 0.2 U
20 U 20 U
2U 2U
2 UJ 2 U
i:~!!!II!:III~I':~~...":'::.!...., ":~:~:,'.:"I~'I*III~:'~!II
.~\~I!III:I:~I::I~.!:~:;:il::,,:'.::;::I:.~i.i'~:g~ilt",
Thallium
Vanadium
Zinc
Samples COIl~:~ in J~ary 1.~93. .
Shaded area Crrd depiCtS positIVe detectIOns.
Concentration for surface water safT1)les are in micrograms per liter ~ or parts per billion (ppb)
Concentration for sediment samples are in micrograms per kilogram ~) or parts per billion (ppb)
SW - Surface Water Sample
SE . Sediment SafT1)le
D - Concentration reported from secondary dilution.
J - Concentration is estimated.
R . Unusable results.
U . Undeteded at the indicated quantitation limit.
UJ - Undetected; the associated quantitation limit is an estimated value.
-------
I
~
ISW.Q91 / //
I .~.(:.~:~::::::::::://l
...:..::...."'" i II
.,:-.' ~ ! !
. ~ i I!
\. ! I~
I
I
!
I
I I
I ~~ 1111 0 '00
(
-+
....&50 -
I
.>~
ABANDONED
RAILROAD SPUR
It' .
. .
. .
155 .: :
N S50 -;
!
-I
.-... ---- ....... --.. ............-................... ...---
SW.10
(1300J)
. :----"'''''''''''''''--''-----, ,"-----'
~I
If
~XJMATC SCAI.E (1\1
I'
, '
. '
. ,
, '.........---..............--.
-
. .
. .
. .
. .
. .
. .
. .
,-......--........----..-
N 250 -'
AREA 2
, '
. .
: :
. .
. . . : : : t I
.....'m.....,....mm..... ......~.............. .:: .JJ i
N..$.. .....-.............. "'---"''''............................ ..---.......................- ..... --.....
) P~LOT~ .:::.-::: --~-----:~96~rlil
\ "
i '...--......-----......'
-I NS-13 LEGEND
\ (~)~
;-- I~I \
I~
~/
. N5-14
(NO)
-
-
100
tJ' i
18 ~ LAGOON
~ 1
~
ASW.14
(590)
~~
I I I I
E250 e
.c5O '
1
E.s50
CHAIN UNK FENCE
~ACE WAteI
LOCA'nON AHO 1.2«A
~T1ON(pCICI)
MONrTOANG WELL
LOCAT1ON AND 1.2«A
CONCENTRAT1ON (pCICI>
FIGURE 8
SURFACE WATER SAMPLING
LOCATIONS ALONG THE
NORTHEAST TRIBUTARY AND
ASSOCIATED CONCENTAA TIONS
OF 1,2-DICHLOROETHANE
-------
HtSO -
NSSO -
N2SO -
N.-SO....
CHAIN UNK PENCE
AREA 2
RAILROAD SPUR 7
'55 ''
* t
I
i
a.
'SE-10
(610)
PARKING LOT-
I
i
t
I
O »
-«o' '
LAGOON
1
LAGOON
2
i i i i
E-3SO
APPROXIMATE SCALE (R)
joo
LEGEND
ASE-13
(290)
STREAM SEGMENT SAMPLE
LOCATION AND 1J-OCA
CONCENTRATION (ppO)
FIGURE 9
SEDIMENT SAMPLING LOCATIONS
ALONG THE NORTHEAST TRIBUTARY
AND ASSOCIATED CONCENTRATIONS
OF 1,2-DlCHLOROETHANE
-------
NATOW. STAAOII Cl&1CAL CCJlllAIfY ~ sm
AEc:ioAo OF DEa8cN IaI 0Pewu UIIT 83
-34-
Surface water and sediment samples were collected on three occasions from the Northeast
Tributary just prior to its leaving the NSCC property. The first samples (sampling location NS-
W2IS2) were collected in June 1987, the second set of samples were collected In July 1990
(sampling location SW/SE-15), and the last time in June 1991 (again, at sampling location SW-
SW-15). As can be seen in Table 6, no contaminants were detected downstream of the plant
prior to the stream leaving the NSCC property which indicates that under nonnal weather
conditions, no contamination is leaving the Site via the Northeast Tributary.
Surface water and sediment samples were also collected to perform toxicity tests as part of the
environmental assessment of this stream. The results of the environmental exposure assessment
are discussed in Section 6.6.
The Northeast Tributary is not specifically classified due to the low flow conditions within the
stream, however, it is considered as a Class .C. stream under North Carolina Administrative
Code, Title 15A, Subchapter 28 (NCAC 15A-28.02) because the receiving stream of the
Northeast Tributary, Grants Creek, is classified as a Class C stream. A Class C stream is defined
as being suitable for secondary recreation and the .propagation of natural trout and maintenance
of trout.. Neither sport nor commercial fish species were observed in the surface waters during
the RI field work.
5.4 HYDROGEOLOGICAL SEmNG
The groundwater beneath the NSCC property is designated as Class GA In accordance with
North Carolina's water classification system and Class itA under USEPA Groundwater
Classification Guidelines (December 1986). The Class GA classifications means that the
groundwater is an existing or potential source of drinking water supply for humans as specified
under North Carolina Administrative Code, Title 15, Subchapter 2L (NCAC 15-2L.02). EPA
classifies the groundwater as Class IIA since the aquifer is currently being used as a source of
drinking water in the vicinity of the NSCC facility. Therefore, the groundwater needs to be
remediated to a level protective of public health and the environment as specified In Federal and
State regulations governing the quality and use of drinking water.
At the NSCC site, a thick mantle of residual soil extends from the ground surface to the bedrock.
This mantle, the saprolite, is composed of clay-rich residual soils which range from silty to sandy
clays. The saprolite is derived from the intense chemical weathering of the crystalline bedrock
and has retained the structural fabric of the parent materials below the oxidation profile. These
residual soils exhibit increasing amounts of sand-sized relict mineral grains below the oxidation.
horizon and closer to the bedrock. There appears to be a complete gradation from
saprolite/friable weathered bedrock, to fractured bedrock/sparsely fractured bedrock. The depth
to bedrock ranges from 10 to 100 feet below ground surface. The deepest bedrock was
encountered was in the vicinity of the Northeast Tributary. Figure 10 shows the orientation of the
hydrogeological cross-section of the Site which is displayed in Figure 11.
Soil fissures near the water table are filled with geothite, presumably derived from the weathering
of the iron-bearing minerals present in the parent rock. There appears to be no confining layer
between the saprolite and bedrock. Therefore these two lithologic units are hydraulically
interconnected, and there is little or no impedance between these two zones.
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NATDW. STARCH . CI&CtoL COIIJ"" ~ !W
~ r:E De080II FOR 0Pewu U8IT 13
-35-
The lithology of the soils underlying the Site was determined from drilling logs. The thickness of
the soil mantle varies across the Site. It appears that Area 2 occupies a structural high and that
the bedrock surface slopes steeply away from this area to the east and more gently to the north.
Rock core records show that the upper 10 to 15 feet of bedrock is deeply weathered and friable.
Bedrock begins to appear nonfriable and tresh 15 to 25 feet below the bedrock/saprolite interface.
However, fractures continue to be frequent and fracture surfaces often exhibit oxidation staining
to depths of 40 to 100 feet below the bedrock/saprolite interface. Fracture frequency diminishes
downward from the bedrock/saprolite interface. It has been estimated that the bedrock becomes
competent approximately 200 feet below ground surface.
Water level measurements from the water table/saprolite zone of the aquifer Indicate that
hydraulic heads decrease from both the east and west towards the Northeast Tributary and
towards the north along the stream. This data indicates that the Northeast Tributary acts as a
groundwater divide for the saprolite zone of the aquifer and receives groundwater discharge along
its entire reach. This explains the presence of contaminants being detected in the surface water
and sediment of this tributary. Additional data needs to be collected during the RD to determine
where groundwater in the bedrock zone of the aquifer is discharging.
The hydraulic conductivity of the saprolite materials and the bedrock ranges from 0.72 to 3.35 feet
per day (ftlday) and 0.01 to 1.13 ftlday, respectively. Based of the above Information, the
horizontal flow of groundwater in the saprolite was estimated to have a velocity of 80 feetlyear
(ftlyr) in the lagoon area and 27 ftlyr in Area 2. Additional information will be collected during the
RD to better define the horizontaJ flow velocity in the bedrock zone of the aquifer.
5.5 PATHWAYS AND ROUTES OF EXPOSURE
The chemicals of concern for groundwater are listed in the Table 8. This list includes VOCs, a
SVOC, and metals. Contaminants were included in Table 8 if the results of the risk assessment
indicated that the contaminant might pose a significant current or future risk or contribute to a risk
which is significant The criteria for including contaminants in this table was a carcinogenic risk
level within or above the acceptable range (Le., 1 E-4 to 1 E-6) or a hazard quotient greater than
0.1. Contaminants were also included if they exceeded either State or Federal applicable or
relevant and appropriate requirements. 1,2-DCA is the only the chemical of concern detected in
the surface water.
An exposure pathway is the route or mechanism by which a chemical agent goes from a source
to an individual or population (i.e., the receptor). Each exposure pathway must Include the
following:
.
A source or mechanism of chemical release to the environment
.
A transport medium (e.g., soil, groundwater, air, etc.)
An exposure point (where a receptor will contact the medium)
.
.
An exposure route (i.e., ingestion, inhalation, or dermal contact).
A pathway is considered complete when all of the above elements are present
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NATDW. STARCH I Cl&1CAL ea.Mtf 9JIBI:uc) SITE
~ t:E 0Eaa:II FeR 0Pswu UIIT t3
-36-
Based on the information collected during the RI, the four transport mechanisms occurring at the
NSCC site are:
. where soils exhibit high levels of contaminant, infiltration of recharge will form leachate,
which will transport the dissolved contaminants downward to the water table
.
once contaminants have reached the water table, the dissolved contaminants will be
transported with groundwater
. where contaminated groundwater discharges to a surface water body, the contaminants will
mix with the surface water and be transported downstream
. where contaminants in the water exhibit an affinity for partitioning to organic carbon, some
contaminants may become adsorbed to the surface sediment in the receiving stream and
may be transported with stream bedload during flooding.
The air pathway was qualitatively evaluated but not quantitatively evaluated as an exposure
pathway for volatilized chemicals and particulate emissions from surface soils for the following
reasons:
1) Much of the Site is covered with either concrete or asphalt;
2) Five VOCs were detected in surface soil; and
3) Each of the VOCs detected were at low concentrations, the highest concentration for each
contaminant detected in the surface soil are listed below:
Contaminant
acetone
2-butanone
chloroform
1,2-DCA
toluene
microoram per kilooram (uolka)
3,500
25
2
15
4
Potential current and future human exposure pathways are summarized in Table 9. This table
presents potential routes of exposure, potential receptors, an evaluation of pathway
completeness, and an assessment of exposure potential. As can be seen, there are no current
complete exposure pathways that pose an unacceptable risk to human health or the environment.
Since use of the land surrounding the NSCC facility is a mixture of residential and commercial,
it is possible that the Site may be used as either residential or commercial area in the future,
therefore, both scenarios were evaluated and incorporated into Table 9.
In summary, the following pathways were evaluated in the risk assessment:
.
Potential current exposure under current land use conditions outside plant operations area
to contaminants in surface water and sediment and springs through incidental ingestion and
dermal contact, and inhalation.
-------
N 1300 -
...--..--
g
~
~
~ N 300=
SCH.E lit
..... - --..,
,....,.-- --
. ,.--
N 0.00 -
l£OE.NO
.
SBA2.2
A
NS.14
u.,.."...-- --
..._~
.M ..,....
--_u IIUat(O
-..---
r-
0II0aI fUV.~
:"'OUII
N -700
E-3200
o
;:
-------
I
ICOtMO
f WMv nMi Etonian
FIGURE 11
HYDROGEOLOGIC CROSS SECTION A-A*
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NATDW. STARCH . Ctelr.AL CalFWI' ~ Sni
REcaI) (S DeaaoN RJI CHrwI.E UIIT 13
-39-
TABLE 8
LIST OF CHEMICALS OF CONCERN IN THE GROUNDWATER POSING RISK
AND THE ASSOCIATED UPPER CONFIDENCE LIMITS (95%) exPOSURE
POINT CONCENTRATION
EXPOSURE POINT CONCENTRATION
FOR CONTAMINANTS DETECTED IN
GROUNDWATER (mg/l)
:v6Giit~;'O~~A~tE;:CoMp~6~'~~:::,"':~~::':'::,:;::f:,~::;'::"':.....::~':',::;,~:::~:::,:,:,:::,,::::;::':::::;:'~::::':::::::::;::":::'::';:::,::::::'::::::::':::::;::::::::::::":::::::::::::::~::;i:',:::;':,::,;:::';:::::::~:';,::':~;::::::::":,::j::::::::::~~:::::::::::::::j::::::,:::
Acetone NA
Bis 2-Chloroeth I ether 0.04
Chloroform 0.00522
1,2-Dichloroethane 0.431
1,1-Dichloroethene 0.0071
1 ,2-Dichloroethene cis and trans NA
1 2-Dichloro r ane NA
Meth lene Chloride 0.00603
Tetrachloroethene 0.00478
1,1,2- Trichloroethane 0.00478
Trichloroethene 0.00446
Vinyl Chloride 0.011
,:S""":E':::'y':'::LV":""'o':::::':'LA"':::':::;:':r:::::"I';::L:::"E':':OR":::::::';:::G:' :'A:':'}N"{'I.::ctC':"'O:":;:::M':~::;::P::':.:::o":'::'U::::'N":'::'os:';:\':.:':;:::::':.:;:::::::;::::::::::::;:'~:::::::::::::::::::::::::::::::;::::::::;:::~:::::::,:::::::::::::::::::::::::,:::f:::';:::::\::::::"::;::::::::::::::::::,:::::::::~;::::::::;t:::::::::::;::::;::::::::::::::
r-: ,', ';,. ".',",'.'.',','.','.',",'.:.;.'.:.;.;.:.;.'.',';.'.;.:,;,:,:,',",",:,',:,:,:,','-:':':';':';".:.:-:.".'.:.:."'.:.",',',,',",,",',:,",',",",.",,',:,',",;",'0'.'.;.','.'.:.:.:.;,'.;:-;.;.:.;"."",",',:',',' ',;.','.'
Bis(2-Ethylhexyl)phthalate
CONTAMINANTS OF CONC,ERN
IN THE GROUNDWATER
0.0185
0.00194
0.257
0.000667
0.00311
0.0414
2.73
0.00104
0.0759
1.34
Antimon
Arsenic
Barium
Be Ilium
Cadmium
Chromium
Man anese
Thallium
Vanadium
Zinc
NA - Chemical was not carried through the risk assessment but is listed as a contaminant of concern
because it exceeds either State and/or Federal groundwater standards in some monitoring wells.
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NA nOlW. Sf ARCH & CI£IIICAl CoMPANY SlJpEAAJl) SITE
RECORD OF DEaSlON FOR OPEAAti UIIT 83
TABLE 9 POTENTIAL CURRENT AND FUTURE EXPOSURE PATHWAYS OF HUMAN EXPOSURE To CONTAMINANTS
INCLUDED IN RISK
ASSESSMENT?
CURRENT
LAND USE
RECEPTOR
MIGRATION/EXPOSURE
PATHWAY
REASON FOR
INCLUSION/EXCLUSION
:::::solllli:j:!:j!!~!::!;:j:::::~:j:jj:!~\j;jj:j::::fj:!!:!j:~::i~~["t.
CHILDREN
ADULTS
n:identaJ Ingestion 01 surface soils
Yes Yes
Yes Yes
No Yes
Danna! contact with surface sons
n:identaJ Ingestion 01 subsurface soils
Dermal contact with subsurface soils
No
Yes
SlIface soR Is currenUy available lor contact by on-site
rece tors
Surface soil Is currenUy available lor contact by on-site
rece tors
Subsurface son Is currently unavailable for contact.
Future development could expose subsurface soil for
Mure receptors. Children may ingest significanUy more
soH than adults.
Future development could expose subsurface soil for
Mure rece tors
Contaminant may migrate from soli to groundwater
StIface soli Is emenUy available for contact by on-site
race rs
Strface soils cmenUy available for contact by on-site
race ors
Stmrface soils COO'8f1tIy I118valable tor contac:t.
Fut1J8 development cWd expose sWuface soil tor
. fut\n race as.
Slmrface soils COO'8f1tIy I118vdable tor contact.
Fut1J8 development cWd expose smutace soil b
futIn tors.
CHILDREN
~tion of contaminants from soil to
=ter. creek. and springs. Exposure via
. Ingestion, drinking water ingestion,
dennal contact at stream and home. i1ha1ation 01
VOCs at stream and home.
R:ldentaJ Ingestion of Stlface soils
No
Yes
No Yes
No Yes
No Yes
No Yes
Dermal contact will sllface sols
h:IdentaIlngestion 01 Uuface soils
Dermal contact will Ustrface solis
Mgration 01 contaminants from Sits to spmgs;
R:identallngestlon 01 spring watsr
Yes
Yes
Site-nllatBd contaminants are present In the creek as a
resUt 01 grooodwater discharge. Sits-relatBd chemicals
area also likely to be present 11 the springs near the
creek.
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NAnOlW. STARCH & CIEMICAl COMPANY SUPEfIFIIIO SITE
RECORD OF DECISION FOR 0PE1WIlf UNIT 13
-41-
I TABLE 9 POTENTIAL CURRENT AND FUTURE EXPOSURE PATHWAYS OF HUMAN EXPOSURE TO CONTAMINANTS I
INCLUDED IN RISK
MIGRATION/EXPOSURE ASSESSMENT? REASON FOR
RECEPTOR PATHWAY CURRENT FUTURE INCLUSION/EXCLUSION
LAND USE LAND USE
Migration 01 contaminants from Site to springs; Yes Yes Site-related contaminants are present in the creek as a
dermal contact with spring water result 01 groundwater discharge. Site-related chemicals
area also likely to be present 10 the springs near the
creek.
Use 01 groundwater as domestic water source: No Yes Future development could result in a production weB In
lnaestion 01 drinkiOQ water this area
Use 01 groundwater as domestic water source: No Yes Future development could result in a production weB In
dermal contact with water this area
Use 01 groundwater as domestic water source: No Yes Future development could result In a production wen in
inhalation 01 VOCs from household water use this area
ADULT Migration 01 contaminants from Site to spri"9s; No No Adults are not expected to play in springs
ioodental ingestion 01 and dermal contact With
soriOQ water
Use 01 groundwater as domestic water SOtlC8: No Yes Future development could result In a production weB In
ingestion 01 drinking water this area
Use 01 groundwater as domestic water SOtlC8: No Yes Future development could result In a production wel In
dermal contact with water this area
Use 01 groundwater as domestic water SOtlC8: No Yes Fum development could result In a production welln
Inhalation 01 VOCs from household water use this area
CHILDREN Mi~tIon 01 contaminants from Site to creek; Yes Yes Site-related contaminants are present In cr88k water and
Incidental Ingestion 01 creek sdnent ::"ent. Children living In ntSiden1lal area nearby may
In the creek
Mi~ 01 contaminants from Site to creek; Yes Yes Site-related contaminants are present In creek water and
Incidental Ingestion 01 utace water ::rent. Children living In residential area nearby may
In the creek
Migration 01 contaminants from Site to creek; Yes Yes Site-related contaminants are present In cr88k water and
dermal contact with sediment sediment Children living In residential area nearby may
play In the creek
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NA110NAl STARCH & ClEUICAI. CoIIPAHY SUPERFIJI) SITE
~OORD OF D£cISION FOIl OI'ERAIU UtIT 13
-42-
TABLE 9 POTENTIAL CURRENT AND FUTURE EXPOSURE PATHWAYS OF HUMAN EXPOSURE To CONTAMINANTS
INCLUDED IN RISK
MIGRATION/EXPOSURE ASSESSMENT? REASON FOR
RECEPTOR PATHWAY CURRENT FUTURE INCLUSION/EXCLUSION
LAND USE LAND USE
Migration 0' contaminants from Site to creek; Yes Yes Site-related contaminants are present in creek water and
dennal contact with surface water ~dimenl Children living in residential area nearby may
ay in the creek
Migration 0' contaminants from Site to creek; Yes Yes Detected chemicals may volatilize Into air
Inhalation 0' contaminants partitioning to air from
surface waler
ADULTS AI pathways identified above No No Adults are not expected to swim or play in the creek
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NATICIW. STNICH . CIeIICIII. CaiJpNf'( ~ SITE
~ CF DEa8cN FOR CPawu \JIlT IJ
-43-
.
PotentiaJ current exposure under current land use conditions inside plant operations area to
contaminants in surface water and sediment, surface soil, and springs through Incidental
ingestion and dermal contact, and inhalation.
.
PotentiaJ future exposure under future land use conditions inside plant operations area to
contaminants in surface water and sediment, surface soil, and springs
Future exposure of onsite residents to contaminants in the surface water and sediment,
surface soil, subsurface soils, groundwater, and springs through ingestion, inhaJation, and
direct contact;
.
.
Future exposure of potential onsite construction workers to contaminants in soil (surface and
subsurface) through incidental ingestion and direct contact; and to contaminants in
groundwater, surface water, and sediment through direct contact.
6.0 SUMMARY OF SITE RISKS
CERCLA directs the Agency to protect human heaJth and the environment from current and future
exposures to hazardous substances at Superfund sites. In order to assess the current and future
risks from the NSCC Site, a baselinf:! risk assessment was conducted in conjunction with the RI.
This section of the ROD summaries the findings concerning the impact to human health and the
environment if contaminated media (i.e., groundwater) at the Site were not remediated. The
baseline risk assessment for OU #3 is incorporated into the June 2, 1993 OU 13 RI Report which
can be found in the NSCC OU #3 Administrative Record.
The risks posed by Site soils will be summarized in OU 14.
6.1 CONTAMINANTS OF CONCERN
Table 8 provides a comprehensive list of all the contaminants identified as chemicals of concern
in the groundwater at the Site. The contaminants and concentrations of these contaminants
detected in the groundwater are the major contributors to the significant risk for this Operable
Unit. The following sections will concentrate on the risks posed by contaminants listed in Table
8.
The extent of the plumes are shown in Figures 3, 4, and 7 and the concentrations of
contaminants detected in the groundwater are presented In Tables 2, 3, 4, and 5.
There are residents within a three-mile radius to the Site who obtain drinking water from private
wells. The nearest private potable wells are approximately 400 feet north of the NSCC property
line. These private potable wells are completed in the bedrock formation.
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NA11OIW. $TAACH & CIeIICAL Co.,., bsF.JI:I SIn:
REocAD OF DeaacM FtiA 0Pawu \hIT 13
-44-
6.2 EXPOSURE ASSESSMENT
The objective of the exposure assessment is to estimate the type and magnitude of potential
exposures to the chemicals of concern that are present at the Site. The results of the exposure
assessment are combined with chemical.specific toxicity information to characterize potential
risks. The exposure assessment involves the following four (4) major steps:
. characterization of the physical setting and identification of human receptors
. identification of potential land-use scenarios
. Identification of potential exposure pathways
. quantification of intakes.
The following pathways were evaluated in the risk assessment for each of the environmental
media adversely impacted by Site activities. For soils, they included:
. Incidental ingestion of soil
. Dermal contact with soil.
For groundwater, they included:
. Incidental ingestion of groundwater at springs (current)
. Dennal contact with groundwater ar springs (current)
. Ingestion of groundwater as drinking water (future)
. Dennal contact with groundwater during domestic water use (future)
. Inhalation of volatile chemicals partitioning to the air from groundwater during domestic water
use.
Table 8 provides the reasonable maximum exposure concentrations which were used in
calculating the carcinogenic and noncarcinogenic risks associated with each chemical of concern
in the groundwater.
The surface water and sediment pathways were evaluated for a current and future trespasser.
(age 7-16 years) and a future child resident (age 1-12 years) for Incidental Ingestion, dermal
absorption and inhalation exposure to chemicals of potential concern in these media. The
exposure frequency and duration for the trespasser scenario were 143 days per year and 10
years, and 286 days per year and 12 years for the resident scenario. The body weight was 45
kilograms for the trespasser and 22.5 kilograms for the resident. The exposure duration was the
same for exposure to spring water; the frequency of exposure was 71 days per year for the
trespasser and 143 days per year for the child resident.
As stated previously, the contaminants and concentrations of these cOntaminants detected In the
groundwater are the major contributors to the significant risk for this Operable Unit and the only
chemical of concern in the surface water is 1,2-DCA. Although, the Impacted groundwater is not
currently being used as a drinking water source, the aquifer itself is being used as a source of
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HAlDW. $TNIOII ~ COIIPAHY &JIBF.N) SrTE
lEal) OF 0Ea8JI R:II ()ISwU UIIT 83
-45-
drinking water; therefore, this resource should be maintained at drinking water quality. Table 10
lists the specific parameters used to model the site-specific groundwater intakes for au 13. The
exposure point concentrations for surface water outside the plant operations area and inside the
plant operations area in the Northeast Tributary are 1.04 milligrams per liter (mgll) and 1.26 Fngll.
6.3 TOXICITY ASSESSMENT
The toxicity assessment was conducted to further determine the potential hazard posed by the
chemicals of concern for which exposure pathways have been identified. Available evidence is
weighed in regards to the potential of particular contaminants to cause adverse effects in exposed
individuals and to provide, where possible, an estimate of the relationship between the extent of
exposure to a contaminant and the increased likelihood and/or severity of adverse effects.
Cancer slope factors (CSFs) have been developed by EPA's carcinogenic Assessment Group for
estimating excess lifetime cancer risks associated with exposure to potentially carcinogenic
chemicals. CSFs, which are expressed in units of milligrams/kilogram/day"' [(mglkg/dayr'], are
multiplied by the estimated intake of a potential carcinogen, in (mglkglday), to provide an upper-
bound estimate of the excess lifetime cancer risk associated with exposure at that intake level.
The term "upper-bound" reflects the conservative estimate of the risks calculated from the CSF.
Use of this approach makes underestimation of the actual cancer risk highly unlikely. CSFs are
derived from the results of human eJ,lldemiologicai studies or chronic animal bioassays to which
animal-to-human extrapolation and uncertainty factors have been applied.
Reference doses (R,Ds) have been developed by EPA for indicating the potential for adverse
health effects from exposure to chemicals exhibiting noncarcinogenic (systemic) effects. R,Ds,
which are expressed in units of mg/kg/day, are estimates of lifetime daily exposure levels for
humans, including sensitive individuals, which will result in no adverse health effects. Estimated
intakes of chemicals from environmental media (Le., the amount of chemical ingested from
contaminated drinking water) can be compared to the R,D. R,Ds are derived from human
epidemiological studies or animal studies to which uncertainty factors have been applied (I.e., to
account for the use of animal data to predict effects on humans). These uncertainty factors help
ensure that the R,Ds will not underestimate the potential for adverse noncarcinogenic effects to
occur.
The Agency has derived CSFs and R,Ds for the contaminants of concern at the Site for use in
determining the upper-bound ~vel of cancer risk and non-cancer hazard from exposure to a given
level of contamination. These values are provided in Table 11.
6.4 RISK CHARACTERIZATION
The risk characterization step of the baseline risk assessment process Integrates the toxicity and
exposure assessments into quantitative and qualitative expressions of risk. The output of this
process is a characterization of the site-related potential noncarcinogenic and carcinogenic health
effects.
Potential concern for noncarcinogenic effects of a single contaminant In a single medium is
expressed as the hazard quotient (HQ) (or the ratio of the estimated Intake derived from the
-------
NA1QW. STNOt & Cl&1CAl COllIWI' SJIeIuc) SItE
REc:CR) CE DEa9CII RJI QIawu \JIlT 13
-46-
contaminant concentration in a given medium to the contaminant's reference dose). By adding
the Has for all contaminants within a medium or across all media to which a given population
may be reasonably exposed, the Hazard Index (HI) can be generated. The HI provides a useful
reference point for gauging the potential significance of multiple contaminant exposures within a
single medium or across media. The Has and His for the exposure pathways (current and future)
identified at the Site are listed in Table 12.
The HQ is calculated as follows:
Non-cancer HQ = CDI/R,D, where:
CD I = Chronic Daily Intake
R,D = reference dose; and
CD I and R,D are expressed in the same units and represent the same
exposure period (Le., chronic, subchronic, or short-term).
For carcinogens, risk are estimated as the incremental probability of an individual developing
cancer over a life-time as a result of exposure to the carcinogen. Table 12 provides the
computed chemical intakes values along with the calculated risks. Excess life-time cancer risk
is calculated from the following equation:
Risk = CDI x SF, where:
Risk = a unit less probability {e.g., 2 x 10~ of an individual developing
cancer;
CDI = chronic daily intake averaged over 70 years (mgncg-day); and
SF = slope-factor, expressed as {mg/kg-dayr'
Excess lifetime cancer risks are determined by multiplying the intake level with the cancer potency
factor. These risks are probabilities that are generally expressed in scientific notation (I.e., 1 x
10041 or 1 E-6). An excess lifetime cancer risk of 1 E-6 indicates that, as a plausible upper-bound,
an individual has a one in one million chance of developing cancer as a result of site-related
exposure to a carcinogen over a 70-year lifetime under the specific exposure conditions at a site.
EPA has set an acceptable carcinogenic risk range of 1 E-4 to 1 E-6; however, depending upon
site factors, a risk of 1 E-4, may be considered protective. Where the cumulative carcinogenic site
risk to an individual is less than 1 E-4 and the noncarcinogenic HQ is less than 1, a RA is
generally not warranted. If an RA is initiated at a Superfund site, then the Agency strives to
achieve a residual cancer risk of no greater than 1 E-6.
The carcinogenic upper-bound risk for each of the exposure pathways (current and future)
identified at the Site are summarized in Table 13. The cumulative future risk and hazard index
posed by the groundwater at the Site is 2 x 10-3 and 60 for a child, respectively. The only
chemical that exceeded EPA's risk range in surface water and spring water was 1,2-DCA.
6.5 RISK UNCERTAINTY
There is a generally recognized uncertainty in human risk values developed from experimental
data. This is primarily due to the uncertainty of extrapolation in the areas of (1) high to low dose
exposure and (2) animal data to values that are protective of human health. Other major
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NATOIAL STARCH & CeCAL CalPNtf 5u'ERF\N) SITE
REaJAD (E 0eaSCII Fa! 0PeIWU UIIT t3
-47-
uncertainties of the NSCC au #3 human health baseline risk assessment are: uncertainties
associated with predicting future land use, uncertainties associated with estimating chemical
concentrations at receptor locations, uncertainties with the toxicity assessment, and uncertainties
associated with assumptions used in the exposure models. Use of upperbound estimates tends
to overestimate exposure and the effect of more than one upperbound parameter tends to
produce an conservative estimate. The assumption that future exposure concentrations will be
equal to current concentrations increases uncertainty because environmental concentrations
appear to vary over time. And the assumption that residences will be constructed on the plant
operations area under the future land-use scenario also adds to the uncertainty.
Models used to predict exposure concentrations have inherit uncertainties associated with them.
These uncertainties are associated with predicting the movement of the contaminants and the
receptors as well as the assumptions made (e.g., skin surface area, soil adherence tactors, and
absorption coefficients tor soil and water).
6.6 ENVIRONMENTAL RISK
The ecological risk assessment for au #3 evaluated risks to the aquatic and benthic (bottom-
dwelling) organisms in the Northeast Tributary. These organisms can be exposed to site-related
contaminants in surface water and/or sediment. The main ecological contaminant of concern in
this tributary is 1,2-DCA. To determine if there were any effects of 1,2-DCA on the benthic
communities inhabiting the Northeast Tributary, a Rapid Bioassessment Protocol was used to
conduct an ecological field assessment during Phase I of the RI for au #3. Results indicated that
tributary segments with historically elevated 1 ,2-DCA levels (adjacent to the plant operations area)
were devoid of sensitive macrobenthic species and exhibited generally lower taxa richness and
abundance than the reference station. However, the benthic assemblages were not dominated
by taxa known to be tolerant of chemical stress. This portion of the Northeast Tributary is located
near the stream's headwater area. In view of the naturally-limiting factors associated with a
headwater stream of this type, ecological impacts resulting from the presence of 1 ,2-DCA in the
Northeast Tributary could not be determined.
During Phase II of the au #3 RI, chronic toxicity tests were performed on surface water and
sediment samples to further examine the ecological impairments noted during the field
assessment. Surface water tests were conducted using fathead minnows and water fleas, while
amphipods and water fleas were used for whole sediment tests. The measurement endpoints
(survival, growth, or reproduction) did not differ significantly between site samples (containing
elevated levels of 1 ,2-DCA) and reference or laboratory samples (containing little or no 1,2-DCA).
These test results initially suggested that ecological impairments observed in the Northeast
Tributary resulted from natural stresses rather than the presence of 1 ,2-DCA or other chemical
contaminants. However, chemical analysis of surface water samples collected at the same time
and locations as those for the toxicity tests indicated that the level of 1 ,2-DCA in the sample
collected adjacent to the Site (200 ugll, estimated value) had decreased below historic levels for
that area (800-3200 ugll) and was below the screening level (2000 ugll) thought to be potentially
toxic to aquatic organisms.
-------
-48-
NATIONAL STARCH a CIEMICAI. COMPANY SUPEAFlJIO SITE
RECORD Of DECISION fOR 0PERA8lf UNIT 13
TABLE 10
Pathwayl
Parameter-
PARAMETERS USED To DESCRIBE EXPOSURES To SITE-RELATED CHEMICALS OF CONCERN
Current Land Use
Current Conditions
Outside Plant Operations
Area
Future Conditions
Inside Plant Operations
Area
;:;;BII~ftl:::III..i!llIlli::III.iltl.'tl;:.::::i::.i;!i[[[ ...
Cw
Age
IR
FI
EF
ED
BW
AT-Noncancer
AT-Cancer
Future Land Use
(Resident)
Reasonable Maximum
Exposure
q n. ... uP
..... ....
",".,",'.','.....,',..',',','
.............,......
..""" ..."..... .
',',',',"."'.".',',..',".,',".','.'
.....,'.............
... """"" '.....
...................
.. .... '..........
..................
.......". . ......
....
"'"
. ...."'"
..'. ."'" n...'
UCL or maximum
conevntration in groundwater
0-30 years
2 Uday
1 unitless
350 days/year
30 years
70 kg
10,950 days
25,550 days
Reference(s)1
Justification
....
. ..........,- -..':';':',
:.:.;. ;-,-:"':':-.:':"':"';':'.. ...-;'::-.-,':".:':',',-.',-.
.n.... n... ... ........... "
"',-..."'"""""""",,,,,, .....
~ff~:/~~{r\I\j\~~~;\;ff:f;~\t\~t\\~\\(;:~r~t:~~~i~~j~i\~f.;:~~.:
,...
.... ...
..'.'.':'.'
.....
....
......,
......
.... ..
........
---
Assumption (See text)
Upperbound estimates EPA, 1991b
100% of drinking water is assumed to come
from contaminated area (EPA, 1991b)
See text
90% upperbound of time lived in one place
(EPA, 1991b)
-------
-49-
NATIONAL STARCH & CII'IIICAl CoIiPANY SUPalFtHI Site
RECORD OF DECISION FOIl 0PE1WIlE UNIT 13
TABLE 10
Pathway/
Parameter-
PARAMETERS USED To DESCRIBE EXPOSURES To SITE-RELATED CHEMICALS OF CONCERN
Current Land Use
Current Conditions
Outside Plant Operations
Area
Future Conditions
Inside Plant Operations
Area
Future Land Use
(Resident)
Reasonable Maximum
Exposure
1~~~I~I~I~I~IIIIB0@~~0~i~!!!:~RI'0!:~~;.::jjt0~::,j'~~~.:.
Cw UCl or maximum
con\.8ntration in groundwater
Age
SA
CF
PC
ET
EF
ED
BW
A T-Noncancer
AT-Cancer
-
0-30 years
21,500 cm2
0.001 Ucm3
Chemical-specific cmlhr
0.2 hour/day
350 days/year
30 years
70 kg
10,950 days
25,550 days
Reference(s)/
Justification
.. . .... .. .-.
...........................
..."'-''''--''''''
. . . . . . . . . . . .. ... .
........ ...... ....
....................
............. ..,"
...............-.'
....,........, .....
.. ...........
.,.-......".. ...
-:-:.; ;.:.;.:..?1~~t;~fttft~r\~fffrjftttf~ff:;::'::
:::::;:.:::;:::::.:.:;:::::;:;;:;::;:;;.;:::;-;::::;:::::::::::':;:::;:;:::;:;:::::::::;:::::::;.::;:::.:;::'::"
."......" """"""""""'.................................
.::,;";;.:::.:.:'x::;:;:::;:::.::::::'[[[';:::;::::..
--.
Assumption (See text)
Average of whole body for years exposed
(EPA, 1992a)
---
EPA, 1992a
EPA, 1991b
See text
Corresponds to age exposed
-------
-50-
NA nONAl STARCH & CIEIlICAl CoIiPANY SuPalFIItD SITe
RECORD OF DEC:ISION FOR OPEIWILE UNIT 13
TABLE 10
Pathway/
Parameter-
PARAMETERS USED To DESCRIBE EXPOSURES To SITE-RELATED CHEMICALS OF CONCERN
Current land Use
Current Conditions
Outside Plant Operations
Area
Future Conditions
Inside Plant Operations
Area
.1,1181:::1::.:_11.:.::.1111811.:::1::...:'1,.1:..11::..:1.:.:...I.::I::.::.:!:
Ca
Age
IR
ET
Shower
Indoors
EF
ED
BW
A T-Noncanoer
AT-Cancer
"'",,,,,,,,,
... ... ." .." '.."
. .. ... ".".......
'P'
.....
.......... ..
Future land Use
(Resident)
Reasonable Maximum
Exposure
;';';'.""'.'
........
... .....
. ....
Calculated from UCL or
ma~lmum concentration in
groundwater
0-30 years
0.63 m3lhr
0.2 hour/day
16 hour/day
350 days/year
30 years
70 kg
10,950 days
25,550 days
Reference(s)/
Justification
P'" ....... .
... ... "' .
.. .. ......,.. .
.. ..... . ""
""'''''".. ...
:::";:";::::::';:::;:::;:;::';:;" ::;:::;";.:::::::::;:::;";::::::::.;.,.
..... . . :r{~}~~tj;frf~t~~:;:~:;::t::~rr}~:~r:~r;~~~\:
",::;,'[[[" ,
-'-"""""-""""-'.'."""""""" .
.. ..'''.... ..................-..... ........
.........
Calculated values
Assumption (See text)
Average (EPA, 1991b)
Upperbound estimate (EPA, 1991b)
Upperbound estimate (EPA, 1991b)
See text
Upperbound estimate (EPA, 1991b)
-------
1---
NAnONAl STARCH & CIEUICAI. CoUPANY SUPERFlIID SITE
RECORD OF DECISION FOR OPERABlE UNIT 13
-51-
TABLE 10 PARAMETERS USED To DESCRIBE EXPOSURES TO SITE-RELATED CHEMICALS OF CONCERN
Current Land Use Future Land Use
(Chilid Resident)
Current Conditions Future Conditions
Pathway/ Outside Plant Operations Inside Plant Operations Reasonable Maximum Reference(s)/
Parameter- Area Area Exposure Justification
:'p1JI~lnl::lii~i:!IIiI:ii!II.::lflp.~JI.:.:~:j --..........- . ...-.....
, ....... ......
...... ....... ''''''''''..
... n'" ...... "................. .n
... .....'" ........... ""0 . ~:}{~:trrttf~:ttfrti:~::{~:):~:.
.... '"'''''' '...', ........ . ...,. .. .. ............ """''''''''''''
....... '"'''' ... ;..";.;.:-:.;.;.;.;.;.;-:.;.-.;.; ";';':':':-:':';';';:';'"" ...
. ....... ..... .. .. . ". "'" ""' ..
CW UCL or maximum ---
concentration in groundwater
Age 1-12 years Assumed
IR 2 Uday Assumed same ingestion rate as adults
FI 1 Unitless 100% of drinking water is assumed to come
from contaminated area (EPA, 1991b)
EF 350 days/year See text
ED 12 years Corresponds to age exposed
BW 22.5 kg Average years exposed (EPA, 1990b)
A T-Noncancer 4,380 days ED x 365 days/year
AT-Cancer 25,550 days 70 year lifetime x 365 days/year
-------
NATIONAL STARCH & CIEMICAl COMPANY SUPEAFIMD SIn
RECORD OF DECISION FOR OPERAIIl£ UNIT 13
-52-
TABLE 10
PARAMETERS USED To DESCRIBE EXPOSURES To SITE-RELATED CHEMICALS OF CONCERN
Current Land Use
Future Land Use
(Chilid Resident)
Pathway!
Parameter-
Current Conditions
Outside Plant Operations
Area
Future Conditions
Inside Plant Operations
Area
Reasonable Maximum
Exposure
Reference(s)!
Justification
Cw UCL or maximum
concentration in groundwater
Age 1-12 years Assumed
SA 8,900 Average for whole body
(EPA, 1992a)
CF 0.001 Ucm3
PC Chemical-specific cmlhr EPA, 1992a
ET 0.2 hour/day EPA, 1991b
EF 350 daysfyear See text
ED 12 years Corresponds to age exposed
BW 22.5 kg Average for years exposed
(EPA, 1990b)
A T-Noncancer 4,380 days ED x 365 dayslyear
AT-Cancer 25,550 days la-year lifetime x ~65 dayslyear
-------
NATIONAL STARCH & CIEIlICAl COUPANY SuPERFlIID SITE
RECORD OF DECISION FOR 0PERA8l£ UNIT 13
-53-
TABLE 10
PARAMETERS USED To DESCRIBE EXPOSURES To SITE-RELATED CHEMICALS OF CONCERN
Current Land Use
Future Land Use
(Chilid Resident)
Pathwayl
Parameter-
Current Conditions
Outside Plant Operations
Area
Future Conditions
Inside Plant Operations
Area
Reasonable Maximum
Exposure
Reference(s)1
Justification
1.....ifil_:::II.lfll:Bm.;lflfllllt...::.....!I..::......................................
Ca
..
0....
.....
.... .
...
H""'"
...-,
nO.
......-
.......
....
......... .
.... ..
.....
.........
".......
. .
....
. . ....
...
....
.... .
.. .
Age
IR
ET
Shower
Cr Iculated from UCl or
maximum concentration in
groundwater
1-12 years
0.63 m'/hr
Calculated value
Assumed
Assumed same inhalation rate as adults
Indoors
EF
ED
BW
0.2 hour/day
16 hours/day
350 days/year
12 years
Upperbound estimate (EPA, 1991b)
Upperbound estimate (EPA, 1991b)
A T-Noncancer
AT-Cancer
22.5 kg
4,380 days
25,550 days
See text
Corresponds to age exposed
Average for years exposed (EPA, 199Ob)
ED x 365 dayslyear
70-year lifetime x 365 days/year
. Parameters are C. ... concentration In media "x"; IR = Ingestion rate or Inhalation rate (with volatiles); FI = fraction Ingested from source; EF = exposure
frequency; ED = exposure duration; BW = body weight; AT-Noncancer = average time for noncarclnogens; AT-Cancer = averaging time for carcinogens;
SA = surface area exposed; AF = adherence factor; ABS = absorption factor; CF = conversion factor; ET = exposure time; PC = permeability constant.
b UCl-Upper 95% confidence limit
-------
NAT1OtW. STARCH & c.&t1CAL Ct::JIpNtf ~ sm
RECXIID ~ 0£as0N R)A 0PeRAai UIIT «
-54-
I~LE 1 1 SUMMARY OF NONCANCER TOXIC EFFECTS OF CH EMICALS OF POTENTIAL CONCERN
INHALATION ORAL RfDd CRITICAL EFFECT UNCERTAINTY GASTROINTESTINAL
CHEMICAL RfCd (rnglkg/day) AND FACTOFr ABSORPTION
(mg/kg/day) TARGET ORGAN' (Inhalation; oraQ FACTOR'
(Inhalation; oraQ
Acetone ND 1 x 1 0.1 h NA; liver, kidney NA; 1 000 0.9
damage
Bis(2-Chloroethyl)ether ND ND NA; NA NA; NA 0.9
Chloroform ND 1 x 1 0.2 h NA; fatty cyst on NA; 1 000 1 .0
liver, liver lesions
1 ,2-Dichloroethane ND ND NA; NA NA; NA 0.9
1 ,1 -Dichloroethene NDa 9 x 1 0.3 h NAm; hepatic lesions NA; 1 000 0.93
1 ,2-Dichloroethenei ND 1 x 1 0.2 b NA; decreased NA; 3000 0.9
hematocrit and
hemoglobin
1 ,2-Dichloropropane 1 x 1 0.3 h ND NA; NA NA; NA 0.9
Methylene Chloride 9 x 1 0.1 h 6 x 1 0.2 h NA; liver toxicity 1 00; 1 00 1 .0
T atrachloroethene ND 1 x 1 0.2 h NA; hepatotoxicity NA; 1 000 0.9
1 1 ,2-Trichloroethane ND 4 x 1 0.3 h NA; clinical NA; 1 000 0.9
,
chemistry alterations
T richloroethene ND 6 x 1 0.3 k NA; NA NA; NA 0.9
Vinyl Chloride ND ND NA; NA NA; NA 0.9
Bis(2-Ethylhexyl)phthalate NA 2 x 1 0.2 h NA; inaeased liver NA; 1 000 0.9
and kidney weight,
nephrotoxicity
Antimony ND 4 x 1 0" h NA; blood glucose, NA; 1 000 0.05
cholesterol
Arsenic ND 3 x 1 ~ h NA; NA; 3 0.98
hyperpigmentation, '
keratosis
Barium 1 x 1 0" b 7 x 1 ()"2 h Fetotoxicity; 1 000; 3 0.1
increased blood
pressure
Beryllium ND 5 x 1 ~ h NA; ND NA; 1 00 0.001
-------
NATIOIW.. STARQ4 & CielICA CCIifIwr ~ Srn
RE
-------
NATIONAl STARCH & CIEMICAl CoMPANY SUPERFlJIO SITE
RECORD Of DECISION FOR OPERABlE UNIT 13
-56-
TABLE 12 ESTIMATED POTENTIAL FUTURE LAND USE RISK FROM CARCINOGENS
POTENTIALL Y
EXPOSED
POPULATION
CHEMICAL
DERMALL Y
ABSORBED
DOSE
(mg/kg/day)
DERMAL
CONTACT
RISK
INGESTED
DOSE
(mg/kg/day)
INGESTION
RISK
INHALED
DOSE
(mg/kg/day)
INHALATION
OF VOCs
RISK
Child Resident 1,1,2- Trichloroethane 5.22 x 10" 3.31 x 10" 6.99 x 10.5 3.98 x 10" 9.01 x 10" 5.13 X 10.7
1 ,2-Dichloroethane 1.09 x 10'" 1.1 0 X 10.5 6.29 X 10.3 5.72 x 10'" 1.52 X 10.3 1.38 x 10'"
Arsenic 2.52 x 10" 4.50 x 10" 2.83 X 10.5 4.96 X 10.5 NA NA
Beryllium 8.67 x 10" 3.73 X 10.5 9.75 X 10-6 4.19 X 10.5 NA NA
Bis(2-chloroethyl)ether 1.09 x 10-6 1.34 X 10-6 5.84 X 10'" 6.43 x 10'" 1.74 X 10-6 2.09 x 10"
Bis(2-ethylhexyl)phthalate 5.58 x 10-6 8.68 x 10" 1.90 x 1 0'" 2.66 x 10-6 NA NA
Chloroform 6.04 x 10.7 3.68 x 10" 7.62 X 10.5 4.65 X 10.7 1.36 X 10.5 1.1 0 x 10"
Methytene chloride 3.53 x 10.7 2.65 x 10" 8.82 X 10.5 6.61 X 10.7 1.42 X 10.5 2.41 x 10"
Tetrachloroethene 2.98 x 10-6 1.72 X 10.7 6.98 x 1 0.5 3.63 x 10-8 1.62 x 1 0.5 3.25 x 10"
Trichloroethene 9.27 x 10.7 1.13 x 10" 6.51 X 10.5 7.16 X 10.7 1.42 X 10.5 8.50 x 10"
Vinyl chloride 1.20 x 10.7 9.05 x 10" 1.60 X 10'" 3.04 X 10'" 3.82 X 10.5 1.15 X 10-5
Total RISK 5.00 x 10.5 1.62 x 10.3 1.53 X 10'"
Total Media 1.83 x 10~
Adult Resident 1,1,2- Trichloroethane 1.01 x 10.7 6.42 x 10" 5.61 X 10-5 3.20 X 10-6 7.24 x 10" 4.12 X 10.7
1,2-Dichloroethane 2.12 x 10'" 2.14 X 10.5 5.05 X 10.3 4.60 X 10'" 1.22 X 10.3 1.11 X 10'"
-------
NAnONAl STARCH & CIEUlCAl CoUPANY SuPERfIJlO SITE
RECORD Of DECISION FOR 0I'e1WlLE UNIT 13
-57-
TABLE 12 ESTIMATED POTENTIAL FUTURE LAND USE RISK FROM CARCINOGENS
POTENTIALL Y DERMALL Y DERMAL INGESTED INHALED INHALATION
EXPOSED ABSORBED CONTACT DOSE INGESTION DOSE OF VOCs
POPULATION CHEMICAL DOSE RISK (mg/kg/day) RISK (mg/kg/day) RISK
(mgikg/day)
Arsenic 4.89 x 10" 8.74 X 10" 2.28 x 10.5 3.98 x 10.5 NA NA
Beryllium 1.68 x 1 0" 7.24 X 10.5 7.83 x 10-6 3.37 X 10.5 NA NA
Bis(2-chlor09thyl)ether 2.12 x 10-6 2.59 X 10-6 4.70 x 10" 5.17 x 10" 1.40 x 10-6 1.68 x 10"
Bis(2-ethylhexyl)phthalate 1.08 x 10.5 1.68 X 10.7 1.53 x 1 0" 2.14 X 10-6 NA NA
Chloroform 1.17 x 10-6 7.15 x 10.8 6.12 X 10.5 3.74 X 10.7 1.09 x 10.5 8.86 x 10.7
Methylene chloride 6.86 x 10.7 5.14 x 10.8 7.09 X 10.5 5.31 X 10.7 1.14 x 10.5 1.94 x 10"
T etrachloroethene 5.79 x 10-6 3.35 X 10.7 5.61 X 10.5 2.92 x 10-8 1.30 X 10.5 2.61 x 10"
T richloroethene . 1.80 x 10-6 2.20 x 10" 5.23 X 10.5 5.76 X 10.7 1.14 x 1 0.5 6.83 x 10"
Vinyl chloride 2.33 x 10.7 1.76 x 10" 1.29 x 10" 2.45 x 10" 3.07 X 10.5 9.21 x 10"
Total RISK 9.71 x 10-5 1.30 X 10.3 1.23 x 10"
Total Media 1.52 x 10-3
-------
NA notW. Sf ARCH & CIEMlCAl CoMPANY St/PERFtJjD SITE
RECORD Of DECISION FOR OPERABlE UNIT 13
-58-
TABLE 12 ESTIMATED POTENTIAL FUTURE LAND USE HAZARD ASSOCIATED WITH NONCARCINOGENS
POTENTIALL Y
EXPOSED
POPULATION
CHEMICAL
DERMALL Y
ABSORBED
DOSE
(mg/kg/day)
DERMAL
CONTACT
HQ
INGESTED
DOSE
(mg/kg/day)
INGESTION
HQ
INHALED
DOSE
(mg/kg/day)
INHALATION
OF VOCs
HQ
Child Resident 1 ,1 ,2- Trichloroethane 3.05 x 10.7 8.46 X 10.5 4.08 x 10'" 1.02 X 10.1 NA NA
1 ,2-Dichloroethane 1.05 x 1 0.5 1.17 X 10.3 . 6.05 x 10'" 6.05 X 10.2 NA NA
Aluminum 2.21 x 10.3 1.47 X 10.2 2.48 x 10° 8.27 X 10-1 NA NA
Antimony 1.40 x 10-6 7.00 X 10-2 1.57 X 10.3 3.94 x 10° NA NA
Arsenic 1.47 x 10.7 5.00 x 10'" 1.65 x 10'" 5.51 x 10.1 NA NA
Barium 1.95 x 10.5 2.79 X 10.3 2.19 X 10.2 3.13 X 10.1 NA NA
Cadmium (water) 1.98 x 10.7 6.60 x 10-3 2.65 x 10'" 5.30 X 10.1 NA NA
Chromium 3.14 x 10-6 1.26 x 10.2 3.53 X 10.3 7.05 X 10.1 NA NA
Manganese (water) 2.07 x 10'" 8.29 x 10-1 2.33 X 10.1 4.66 X 10' NA NA
Thallium 7.91 x 10-8 2.64 x 10.2 8.88 x 10-5 1.48 x 100 NA NA
Vanadium 5.76 x 10-6 1.65 X 10.2 6.47 X 10.3 9.24 X 10.1 NA NA
Zinc 1.01 x 10'" 5.47 X 10.3 1.14 X 10" 3.80 X 10" NA NA
Total HQ 1.01 x 10° 5.69 X 10' 7.67 X 10-8
Total Media HI 5.79 x 10'
Adult Resident 1,1 ,2-Trichloroethane 2.37 x 10'7 6.57 x 10-5 1.31 x 10'" 3.27 X 10"2 NA NA
1 ,2-Dichloroethane . 8.15 x 1 0-6 9.06 x 10'" 1.94 x 10'" 1.94 X 10'2 NA NA
-------
I .' .
NAnONAl STNICH a CIEI/ICAl Col/PANY SUPERFUND SITE
RECORD OF DECISION FOR OPERAIIl£ UNIT 13
-59-
TABLE 12 ESTIMATED POTENTIAL FUTURE LAND USE HAZARD ASSOCIATED WITH NONCARCINOGENS
POTENTIALLY DERMALL Y DERMAL INGESTED INHALED INHALATION
EXPOSED ABSORBED CONTACT DOSE INGESTION DOSE OF VOCs
POPULATION CHEMICAL DOSE HQ (mg/kg/day) HQ (mg/kg/day) He
(mg/kg/day)
Aluminum 1.71 x 10-3 1."14 x 10.2 7.97 X 10.1 2.66 X 10.1 NA NA
Antimony 1.09 x 10-6 5.44 x 10.2 5.06 x 10'" 1.26 x 10° NA NA
Arsenic 1.14 x 10-7 3.88 x 10'" 5.31 X 10-5 1.77 X 10.1 NA NA
Barium 1.51 x 10.5 2.16 X 10.3 7.04 X 10.3 1.01 X 10"1 NA NA
Cadmium (water) 1.54 x 10-7 5.13 X 10.3 8.52 X 10-5 1.70 X 10.1 NA NA
Chromium 2.44 x 10-6 9.75 X 10.3 1.13 X 10.3 2.27 X 10.1 NA NA
Manganese (water) 1.61 x 10'" 6.44 x 10.1 7.49 X 10.2 1.50 x 10' NA NA
Thallium 6.14 x 10-8 2.05 X 10-2 2.86 X 10-5 4.76 X 10.1 NA NA
Vanadium 4.47 x 10-6 1.28 x 10.2 2.08 x 10.3 2.97 X 10.1 NA NA
Zinc 7.87 x 10.5 4.24 x 10.3 3.66 X 10.2 1.22 X 10.1 NA NA
-
Total HQ 7.81 x 10.1 1.83 x 10° 9.86 x 10.7
Total Media HI 1.91 x 10'
-------
NATOW. STAACH . CI8~ COMPAHY ~ ~
REc:oRc ~ DeasoN FOR ()Ie1Wl.E UIIT 83
-60-
I TABLE 13 SUMMARY OF CANCER RISK AND NONCANCER HI VALUEa
Current Land Use
Receptor/
RISK or HI Current Conditionb Future Conditionc Future Land Used
Child/RISK B x 10-5 1 x 10~ 4 x 10~
ChiidlHl 6 x 10-2 4 X 10-2 1 X 10.'
Adult/RISK NA NA NA
AdultIHl NA NA NA
Child/RISK 4 x 10.9
ChiidIH I 5 x 10.7
Adult/RISK NA
AdultIHl NA
':!'f.'illl:':'~:!:i:",:~::,':':.:.:.'I;:::::I!::i::';;'...:::::::1I.:il;::.I:::j::II::::i.::.1.11.i::::.'i1:1:'.1::..:....::j:.::::~::i.I':i":i:1:'~:':,
Child/RISK 2 x 10-5
ChiidIHl 1 x 10-2
AdultIRlSK NA
9 X 10"' 1 X 10.7
6 x 10.7 6 x 10"
NA NA
NA NA
\\\:::':i.I::,"i'.:i~:II~ljj:'~:~:~~~i:::~.:j:::I:I::j'ji:'li:I.I::lj.1111:1::j:il1II:111li.::j..!;:::j:.::::ij!:~i!jl.:::.j1~I~~.!:II:1::::':'i1:j,ili.'~1I:il:::~::li':'!i1':1:"I:'
AdultIHl
NA
2 x 10-5 1 x 10~
1 X 10.2 3 x 10-2
NA NA
NA NA
::~:_I"i'i!:'::iii':i~.:I:,:I~i:~:::.j:::ii:i.ii:~i!:i:i:1ilii:III~!::i:li::::I::i::::lli::.:!:i:!:I::!i;;:~::il;i!!:';'!':
':', '..""::";"!:'I:'!"::::.;':ii:I!'ilil:iirj:;IJliiiiillr~lfJ.lllt~I;1~:il'illll1iiliiiiill'~;iillir.jii!ijjl:i~1;lil!ii::il:iiiili
ChildJRlSK NA NA 2 X 10-3
ChiidIHl NA NA 6 X 10'
AdultlRlSK NA NA 2 x 10-3
AdultIHl NA NA 2 X 10'
a Values presented are the sum for all exposure pathways associated with the environmental
medium.
b Outside the plant area; the fence successfully predudes access to the plant area.
C Inside the plant area; the fence around the plant area is not functional.
d The NSCC property is available for residential use.
-------
NATOW. STARCH & CIeIICoIi. CoMPNtr ~ ~
RECXJRD CE Deo9CII FOR O»swu l/IIT 13
-61-
6.7 SUMMARY
Actual or threatened releases of hazardous substances. from this Site, if not addressed by
implementing the response action selected in this Record of Decision, may present an imminent
and substantial endangerment to public health, welfare, or the environment. Presently, no
unacceptable current risks were identified associated with the NSCC Site. The unacceptable risks
connected with the Site are associated with the potential future use of the groundwater beneath
and downgradient of the Site as a potable source of water and the potential adverse impact
contaminated soils will have on groundwater quality. The unacceptable, future risk is due to the
presence of contaminants at concentrations above EPA's MCLs for drinking water and the State
of North Carolina groundwater quality standards. These contaminants will be remediated during
the remedial action phase.
Presently, no substantive link has been made between the presence of 1,2-DCA in the Northeast
Tributary and the limited biodiversity in this stream as the area of the stream impacted by the Site
is approximately 1,500 feet from the head-water of this stream. However, the RI report did
conclude that the source of 1,2-DCA in the Northeast Tributary is the contaminated groundwater
in the saprolite zone of the aquifer discharging into this stream. Since very high concentrations
of 1,2-DCA (660,000 ~/I) have been found in the groundwater, the potential for discharge of
groundwater contaminants above levels of ecological concern is possible. Hence it is necessary
to institute long-term monitoring of ~he Northeast Tributary.
7.0 REMEDIAL ACTION OBJECTIVES
Section 5.0 defined the extent and characterized the contamination and the environmental setting
of OU #3. Section 6.0 highlighted the human health and environmental risks posed by the Site.
This Section specifies the remedial action objectives to protect human health and the environment
by preventing exposure to the contaminants in the groundwater and surface water/sediment
associated with OU #3.
The specific remedial action objectives and general response actions for the environmental media
adversely impacted by the Site addressed in this ROD are listed in Table 14.
7.1 APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS (ARARS)
Section 121 (d) of CERCLA, as amended by SARA, requires that remedial actions comply with
requirements or standards set forth under Federal and State environmental laws. The
requirements that must be complied with are those laws that are applicable or relevant and
appropriate (ARAR) to the (1) remedial action(s), (2) location, and (3) media-specific
contaminations at the Site.
Applicable requirements defined in 40 C.F.R. ~ 3oo.4oo(g)(1) are those requirements applicable
to the release or RA contemplated based upon an objective determination of whether the
requirements specifically addresses a hazardous substance, pollutant, contaminant, RA, location,
or other circumstance found at a CERCLA site. These requirements would have to be met under
any circumstance. Relevant and appropriate requirements defined.in 40 C.F.R. ~ 3oo.400(g)(2)
are those requirements that address problems or situations sufficiently similar to the
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NATIOHAL ST~ & c.e.1CAI. CalPNtf ~ Sm
REcoAo ~ DEaaoN FOR C)IawU UIIT t3
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circumstances of the release or removal action contemplated, and whether the requirement is well
suited to the Site. The action-, chemical-, and location-specific ARARs for the selected remedial
alternative are listed in Table 17.
7.2 EXTENT OF CONTAMINATION
The extent and volume of contaminated soils will be addressed in OU '4 ROD.
Figures 3, 4, and 7 delineate the estimated periphery of the plumes in the groundwater
associated with OU 13. These plume estimates are based on contamination levels detected in
the groundwater as well as where there were no detections of contaminants in the groundwater.
I:
CalculatioRs were performed to estimated the volume of groundwater which needs to be
remediated. By using an estimated surface area of 748,481 square feet, a saturated aquifer
thickness of 26 feet in the saprolite and 100 feet in the bedrock, and an aquifer porosity of 35
percent in the saprolite and 5 percent in the bedrock, the quantity of contaminated groundwater
in one pore volume of the aquifer was estimated to be 131 million gallons.
8.0 DESCRIPTION OF ALTERNATIVES
Due to an insufficient evaluation of soil remediation technologies in the June 21, 1993 FS
document, this ROD will only address the remediation of groundwater and surface
water/sediment. Soil remediation in Area 2 and lagoon area will be addressed in OU M.
Table 15 inventories those technologies that passed the initiaJ screening for remediating the
contaminated groundwater and surface water/sediment at OU 13. In the initial screening, process
options and entire technologies were eliminated from consideration if they are difficult to
implement due to Site constraints or contaminant characteristics, or if the technology has not
been proven to effectively control the contaminants of concern. Table 15 also presents the
results of the final screening of the groundwater remediation technologies. Effectiveness,
implementability, and relative capital and operation and maintenance costs are the criteria used
for evaluating the technologies and process options in the final screening. The process options
that were retained for further evaluation are boxed in by a bold line. This table provides the
rationale as to why certain technologies were not retained for the detailed comparison.
The five (5) groundwater remediation alternatives retained to address the estimated 131 million
gallons of contaminated groundwater and the two (2) surface water/sediment remediation
alternatives are described below. .
8.1 REMEDIAL ALTERNATIVES TO ADDRESS GROUNDWATER CONTAMINATION
Although the groundwater alternatives for addressing contaminated groundwater for Area 2 and
the lagoon area were considered separately in the FS, they were combined in this ROD. Area
2 alternatives are identified by -P- for the -Plant- and the alternatives deaJing with the
contaminated groundwater associated with the lagoon area are identified by -L- for -Lagoon
Area-.
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NATIONAL STARCH & CletICAl. ea.>Ntf ~ SITE
REccAo (6 0EasDI FOR 0PewI.E UIIT t3
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Alternative GWP1/GWL 1 :
Alternative GWP2IGWl2:
Alternative GWP3/GWL3:
No action
Long-Term Monitoring with Fencing A Portion of Northeast
Tributary .
Institutional Controls with Fencing A Portion of Northeast
Tributary
Groundwater Extraction, Air Stripping, Vapor-Phase Carbon
Adsorption, Discharge to Publicly Owned Treatment Works
(POTW) (i.e., local sewer system)
Groundwater Extraction, Air Stripping, Fume Incineration,
Discharge to POTW
Alternative GWP4A1GWL4A:
Alternative GWP4B/GWL4B:
The point of compliance for all the groundwater alternatives listed above for OU #3 is defined as
throughout the entire plume of contamination in accordance to 40 CFR 3oo.430(a)(1 )(iii)(F) which
states "EP A expects to return usable ground waters to their beneficial uses wherever practicable,
within a timeframe that is reasonable given the particular circumstances of the site. When
restoration of ground water to beneficial uses is not practicable, EPA expects to prevent further
migration of the plume, prevent exposure to the contaminated ground water and evaluate further
risk reduction."
8.1.1 ALTERNATIVE GWP1/GW.1: No action
The No Action alternative is included, as required by CERCLA, to establish a baseline for
comparing the benefits achieved by the other groundwater remediation alternatives. Under these
alternatives, no cleanup activities would be implemented to remediate the groundwater adversely
impacted by past Site activities (Le., the Site is left "as is"). Because these alternatives do not
entail contaminant removal or destruction, hazardous materials would remain on Site requiring
a review of the Site remedy every five years in accordance with CERCLA Section 121(c). The
implementation of this remedy could begin immediately and would have no negative impact on
future remedial actions.
A slight reduction in the levels of contamination may occur over time through natural processes;
however, the levels in the groundwater would remain above the groundwater cleanup goals for
up to 70 years. Although there is no current unacceptable risk associated with the contaminated
groundwater, this situation would change immediately if a potable well was installed near the Site.
The reason there is no current risk is because nobody in the vicinity of the adversely impacted
groundwater is using this groundwater as a source of drinking water. However, if a potable well
was installed in or near the plume, the risk would increase to 2 x 104. Since this alternative does
not involve any treatment or other remedial action, the reduction in the toxicity, mobility, or volume
(TMV) of the contaminated groundwater at the Site would result from natural processes.
There are no capital costs associated with this alternative; however, operation and maintenance
(O&M) costs woulcl be incurred for conducting the five year reviews. This review includes
monitoring the groundwater under the Site once every five years as well for a period of 30 years.
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NArow. STARCH I C+el1C4 Ct»wr ~ SITe
RE
-------
Oener.1
Reapon..
Action
Net AciIDn
hillIuIIonII C4naI
CcIIUInmn
eo.".....MJI'IIIJn8II
CcII8dIonIOIII:
CoIIdkWf
Technology Type
Pr0C888 Option
m.lnutlone'
Implement_Hby
E8IIf .....11111l1li8
~ ...........
,'........
II'.""'"
II~~.........
..........
11..._"'"
Hat 1ImpIta'l8ll11188 far II8dIadI
In~..""" witt....... ~
..............
I II.~.........~
......U1118 wlhllllkullr
111,*,,1_""
'..,...-'1 ...~
Na8 II.......... far.....
E.-, II...."""'. Nt &... .~
......CanRI8d
~ ......,.. 1'"
.............
.,...~........
tn........ T~""
........... wIh ......,
........l18li wIh IMaII1
Eff8ct1vene8.
In ......ng PRae
NIle EIIIdIwe
~E"'"
Hal EIIdh8. W'" NMdI
T....... to MIlle PAQe
E"'"
808u8WII8I EIIdh8
Hal EI8dM. W.. NMdI
T.......10 MIlle PAG8
YIIY UIaIN
YIIY EIIIIIIIM
Na8 E8IaIM "~AIIIAr
YIIY .....
YIIY ......
.....
E~
~ E""'....
~E""
.....-.., EIIdh8
TABLE 15 SECOND SCREENING OF TECHNOLOGIES AND PROCESS OPTIONS FOR GROUNDWATER
H ~A I
~I
~CcdaI~w.i::J
H
H
WA
ACOI8 RwIoe.a....
~-:=-~
CcIIMnIb. ~ WIll
E88dIDft
fjllllno8d edI~. WIll
........ [hila
TIWIdI
In"""
Qt.8h
o.ee.
~
........ 0IIII8D8
car POTW
~... EIIr8dIan WeI8
EIndIDn
EIIII8I1C18d 8IIr8CIon WIll
......... [hila
TIWIdI
,.......
CIIbon
.....
0ItdIIaft
a-blT--
cu.. Ph6....
A8nIIIIo BIoI--
"-. ......
"-Io~
...
....,. ...
....... ...
lIII8 to""'"
......
...
....,. ...
....,. ...
MDdIr8
........ ...
...
. ""_IIt",
IIDdInI8ID ~
C088
lIII8
a.c.
a.c.
...
...
-------
Gener.I
R..pon.
Action
CoI8dIanf1'
I
Technology Type
On-8IIe 0tIcIwge
0888
I- Pr.- 0pIbI""'"
~~
PI0C888 Option
"1II8IIon
iiion
POtW
. SuIf8I8 W88Ir
In.'"utlol18l
Impl8menl8bHIty
: .............. will Mod8nIII DIIIaIIr
. ...~)~....
..--1.."'" will Mod8nIII DIIIaIIr
~I.."'''''~
Effectl".....
In ""'1"1 PRGe
EIIIcIIN
EIIIcdw8
EIIIcIIN
EIIIcIIN
TABLE 15 SECOND SCREENING OF TECHNOLOGIES AND PHOCESS OPTIONS FOR GROUNDWATER
Co8t
Law 10 ........
Law
~--
...,.
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NAT1OIW. STAAl)! . c.e.~ CQ/IIwr ~ ~
RECORD (;E DEasoI FCA 0PawI.E UIIT «3
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Capital Costs:
Annual O&M Costs:
Total PW Costs for 30 Years:
Time to Design:
Construction Time:
Duration to Achieve Clean-up:
$ 0
$ 22.000
$ 227,000
None
None
Over 30 years
8.1.2 ALTERNATIVE GWP2IGWL2: Lona Term Monltorlna and Fenclna
A Portl~n Of Northeast Trlbutarv
This alternative is analogous to Alternative GWP1/GWL 1, except under Alternative GWP2IGWL2.
additional monitoring wells would be installed, groundwater monitoring data would be collected
annually instead of once every five years, and a portion of the Northeast Tributary would be
fenced. Extending the existing fence line to inclose additional portions of the Northeast Tributary
is a precautionary action to reduce the future likelihood of exposing children to unacceptable
levels of contaminants in the Northeast Tributary via dermal absorption, ingestion, and/or
inhalation. As stated in Section 6.0, the current levels of contaminants in the Northeast Tributary
do not pose an unacceptable risk. However, under this alternative, the contaminated groundwater
is not actively remediated which could lead to higher levels of contarninants entering the
Northeast Tributary along with the :roundwater. This increase in concentrations of contaminants
entering the stream may result in unacceptable exposure concentrations in either water column
or sedirnent or both.
Capital Costs:
Annual O&M Costs:
Total PW Costs for 30 Years:
Time to Design:
Construction Time:
Duration to Achieve Clean-up:
$ 178,000
$ 138.000
$1,479,000
None
None
Over 30 years
8.1.3 ALTERNATIVE GWP3/GWL3: Instltuttonal Controls. Lona Term Monltorlna. and
Fenclna A Portion Of Northeast Trlbutarv
This alternative is identical to Alternative GWP2IGWL2, except Alterative GWP3/GWL3 includes
institutional controls. No remediation activities would be conducted for groundwater. The
additional costs are associated with preparing and filing deed restriction(s) and implementing any
other institutional controls. The specific institutional controls to be implemented include: using
deed restrictions to control the installation of new wells on plant property; track plume migration;
and install fencing around the Northeast Tributary to limit access to contaminated surface water
and sediment.
This alternative provides no reduction in TMV of the contaminants; however, it can reduce or
eliminate direct exposure pathways and the resultant risk to the public. As part of this alternative,
the groundwater would be monitored on a yearly basis. As EPA may not have the authority to
implernent these institutional controls, the responsibility rests on the PRP ensure the institutional
controls are in place, are reliable. and will remain in place after initiation of O&M. Groundwater
monitoring and the five year CERCLA review would be conducted for 30 years.
-------
Capital Costs:
Annual O&M Costs:
Total PW Costs for 30 Years:
Time to Design:
Construction Time:
Duration to Achieve Clean-up:
NArow. ST~ &. CIeIICIoL CoI8>AN'f ~ Sm
REcORD (E CEasIoN FeR 0PsIAai UIIT 83
-68-
$ 198,000
$ 138.000
$1,500,000
None
None
Over 30 years
8.1.4 ALTERNATIVE GWP4A1GWL4A: Groundwater extraction Throuah Wells;
Treatment bY Air StrlDDlna with VaDor-Phase Carbon AdsorDtlon;
and Dlscharae to POTW
This alternative includes extracting groundwater by means of extraction wells downgradient of
both areas, Area 2 and the lagoon area; volatile organics removal through air stripping; control
of emissions to the atmosphere from the air stripper through vapor-phase carbon adsorption; and
combined discharge with treated groundwater from OU-1 to the Salisbury publicly owned
treatment works (POTW). The treated effluent must meet permit limits set by the Salisbury
POTW. Spent activated carbon would be changed out and sent to a commercial
regeneration/recycling facility, destroyed through incineration, or disposed in an appropriately
regulated landfill. The five year review CERCLA requirement would apply to this alternative.
Capital Costs:
Annual O&M Costs:
Total PW Costs for 30 Years:
Time to Design:
Construction Time:
Duration to Achieve Clean-up:
$1,437,000
$ 740.000
$5,792,000
1 year
6 months
15 to 30 years
8.1.5 ALTERNATIVE GWP4B/GWL4B: Groundwater Extraction Wells. Treatment bY
Air StrlDDlna with Fume Incineration: and Dlscharae to POTW
This alternative is identical to Alternative GWP4A, except that the control of emissions to the
atmosphere from the air stripper would be accomplished through fume incineration.
Capital Costs:
Annual O&M Costs: .
Total PW Costs for 30 Years:
Time to Design:
Construction Time:
Duration to Achieve Clean-up:
$1,679,000
$ 659.000
$5,270,000
1 year
6 months
15 to 30 years
-
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NATIOIW. STARCH' CHEIIICAL Co„>NtY ~ sm:
RE<::IR> CF DEasoc I'OA 0Pswu UIIT 83
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8.2 REMEDIAL ALTERNATIVES TO ADDRESS SURFACE WATER AND SEDIMENT
CONTAMINATION
8.2.1 ALTERNATIVE SWISE-1: No Action
No further activities would be conducted on surface water or the sediment in the Northeast
Tributary. As with Alternative GWP1/GWL 1, this stream would be left -as is-. Samples would be
collected .and analyzed every five years as part of the five year review CERCLA requirement
which would apply to this alternative.
Capital Costs:
Annual O&M Costs:
Total PW Costs for 30 Years:
Time to Delign:
Construction Time:
Duration to Achieve Clean-up:
$ 0
$ 16.000
$151,000
None
None
Over 30 years
8.2.2 ALTERNATIVE SWISE-2: Lona-Term Monltorlna
This alternative is similar to Alternative SW/SE-1, except under Alternative SW/SE-2, surface
water and sediment samples would be collected from the Northeast Tributary annually instead
of once every five years.
Capital Costs:
Annual O&M Costs:
Total PW Costs for 30 Years:
Time to Design:
Construction Time:
Duration to Achieve Clean-up:
$ 0
$ 92,000
$867,000
None
None
Over 30 years
9.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
Section 8.0 describes the remedial alternatives that were evaluated in the detailed analysis of
alternatives set forth in the June 21, 1993 OU 13 Feasibility Study Report. This secti0':1
summarizes the detailed evaluation of these remedial alternatives in accordance with the nine (9)
criteria specified in the NCP, 40 CFR Section 3oo.430(e)(9)(iii). This section summarizes the
comparison of the groundwater and surface water/sediment remedial alternatives; the soils
remedial alternative will be addressed under OU 14.
9.1 THRESHOLD CRITERIA
In order for an alternative to be eligible for selection, it must be prdtective of both human health
and the environment and comply with ARARs; however, the requirement to comply with ARARs
can be waived in accordance to 40 CFR Section 300.430(f)(1)(ii)(C). Table 16 summarizes the
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NA~ $TAAOI . c.e.1CAI. CalPNIf ~ SITE
REaJID OF DEa8CN R)A 0Pawu UIIT 13
-70-
evaluation of the five (5) groundwater and two (2) surface water/sediment remedial alternatives
with respect to the threshold criteria.
9.1.1 OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
This criterion assesses the alternatives to determine whether they can adequately protect human
health and the environment from unacceptable risks posed by the contamination at the Site. This
assessment considers both the short-term and long-term time frames.
Under current conditions, the groundwater does not pose an unacceptable risk to human health
or the environment. And in contemplating future use scenarios for the Site in the Risk
Assessment. the scenario that typically results in manifesting the greatest risk, using
contaminated groundwater as potable water, the overall risk posed by the Site was 2 x 10-3.
.
Alternatives GWP2IGWL2, GWP3/GWL3. GWP4AJGWL4A, and GWP4B/GWL4B, provide
adequate protection for human health' by preventing ingestion of potentially contaminated
groundwater and surface water. Alternatives GWP4A1GWL4A and GWP4B/GWL4B would afford
the greatest protection to human health because it would substantially reduce the contamination
in the groundwater and prevent the potential for exposure through use of existing or future off site
wells. Alternatives GWP4A1GWL4A and GWP4B/GWL4B would indirectly remediate the surface
water and sediment, since the groundwater remediation would decrease the potential for
contaminants to reach the tributary via groundwater discharge. Both of these altematives would .
eliminate the potential for exposure via ingestion of these media. These alternatives protect the
environment by removing contaminants from groundwater, controlling the extent of groundwater
contamination, and reducing the contamination in the tributary and downstream surface waters.
Altemative GWP3/GWL3 would not be as protective of the environment because contamination
would continue to migrate into the tributary through groundwater discharge. Neither Alternatives
GWPlIGWL 1 nor GWP2/GWL2 would provide protection for human health. Natural
degradation/attenuation of contaminants in the subsurface is not anticipated to prevent the
potential migration of contaminants off site, although such processes may reduce the amount and
concentration of contaminants which would eventually leave the Site.
Under present conditions, both Alternatives SW/SE-1 and SW/SE-2 would be protective of human
health. but may not be protective of the environment. If higher concentrations are discharged into
the stream along with the groundwater, then both alternatives may not be protective of human or
the environment.
9.1.2 COMPLIANCE WITH APPLICABLE OR RELEVANT AND APPROPRIATE
REQUIREMENTS
This criterion assesses the alternatives to determine whether they attain ARARs under federal
and state environmental laws, or provide justification for waiving an ARAR. Site specific ARARs
are identified in Table 17.
MCLs and State groundwater quality standards are ARARs for Site groundwater. By leaving
contaminants above these standards in the groundwater, Altern'8tives GWPlIGWL 1,
GWP2IGWL2, and GWP3/GWL3 would not comply with these ARARs. Therefore, these
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NATIOIW. STNDI . C+EIIbl CoIIIPNtf ~ SITE
REc::tq) ~ DEa8JM Fa! 0Pswu UIIT 83
-71-
alternatives would not achieve the requirernents of the NCP. Alternatives GWP4A1GWL4A and
GWL4B/GWL4B would obtain performance standards for groundwater (MCLs and North Carolina
Groundwater Standards), surface water and sediment at the point of compliance. These
altematives would also comply with action- and location-specific ARARs related to the
construction and operation of the groundwater extraction, treatment, and discharge systems to
be installed under these Alternatives. The discharge to the POTW and air emission associated
with Alternatives GWP4A1GWL4A and GWL4B/GWL4B will also satisfy all appropriate ARARs.
The disposal of any sludge or spent activated carbon created by the groundwater treatment
system will also comply with the appropriate ARARs.
There are no Federal or State ARARs for the contaminants detected in the surface water or
sediment originating from the Site. However, the long-term monitoring requirernent associated
with SW/SE-2, if done inconjunction with remediation of the groundwater, would serve to verify
that groundwater contaminants are not migrating into the tributary at levels of concern for human
health or the environment.
9.2 PRIMARY BALANCING CRITERIA
These criteria are used to evaluate the overall effectiveness of a particular remedial alternative.
This evaluation is summarized in ~~ble 18.
9.2.1 LONG-TERM EFFECTIVENESS AND PERMANENCE
This criterion assesses the long-term effectiveness and permanence an alternative will afford as
well as the degree of certainty to which the alternative will prove successful.
Under Alternatives GWP1/GWL 1, GWP2IGWL2, and GWP3/GWL3 groundwater contamination
would not be actively remediated; therefore these alternatives cannot be considered to be
permanent or effective remedial solutions as these alternatives do not remove, treat, or isolate
subsurface contamination. The long-term effectiveness of Alternatives GWP1/GWL 1 and
GWP2IGWL2 is questionable, because of the time it would require for -Nature- to clean -'tselr.
These remedies would rely on the natural attenuation and the flowing groundwater to eventually
remove all the contarninants that have entered the groundwater at the Site. Alternative
GWP3/GWL3 would prevent potential future risk by preventing the installation of drinking wells
in any areas exceeding MCLs or North Carolina Groundwater Standards. Alternatives
GWP4A1GWL4A and GWP4B/GWL4B would provide an effective and permanent solution for
groundwater, surface water, and sediment because the chemicals of concern would be rernoved
from the groundwater and destroyed and prevent them from migrating into the surface water and
sediment of the tributary via groundwater discharge. The reliability of Alternatives
GWP4A1GWL4A and GWP4B/GWL4B is high and these alternatives would not pose a human
health or environmental risk at the point of compliance and no treatment residuals would be left
on Site. Five-year CERCLA mandated reviews will be required for all of the alternatives.
Under current conditions, both Alternatives SW/SE-1 and SW/SE-2 would be protective of human
health, but may not be protective of the environment. If higher concentrations of contaminants
begin discharging into the tnbutary, then neither of these alternatives may be protective of human
or the environment.
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NA11OIW. STARCH . CIeIICAl CCtIP"" &JIsIUI) Snc
RECORD OF DeaSOH FOR 0Pewu IMT 83
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9.2.2 REDUCTION OF TOXICITY. MOBILITY. OR VOLUME
This criterion assesses the degree to which the alternative employs recycling or treatment to
reduce the TMV of the contaminants present at the Site.Alternatives GWP4A1GWL4A and
GWP48/GWL48 would reduce the toxicity and volume of contamination in groundwater through
removat and treatment. They would also reduce the toxicity and volume of contarnination in
surface water and sediment. The groundwater treatment processes associated with these two
alternatives would completely comply with the statutory preference for alternatives that reduce
toxicity of contaminants. Alternatives GWP1/GWL 1, GWP2IGWL2, and GWP3IGWL3 do not
directiy reduce toxicity, mobility, or volume of groundwater, surface water or sediment
contamination.
Alternatives SW/SE-1 and SW/SE-2 could lead to a reduction of VOCs in the tributary; however,
neither of these atternatives would result in the destruction of the VQCs. These contaminants
would transfer from the tributary to the atmosphere through the process of volatilization.
9.2.3 SHORT-TERM EFFECTIVENESS
This criterion assesses the short-term impact of an alternative to human health and the
environment. The impact during ~he actual implementation of the remedial action is usually
centered under this criterion.
All of the alternatives for both groundwater and surface water/sedirnent can be implemented
without significant risk to the community or on-site workers and without adverse environmentat
impacts.
9.2.4 IMPLEMENT ABILITY
This criterion assesses the ease or difficulty of implementing the alternative in terms of technicat
and administrative feasibility and the availability of services and materials.
None of the alternatives for both groundwater and surface water/sediment pose significant
concerns regarding implementation. The design of the treatment systems for Alternatives
GWP4A1GWL4A and GWP48/GWL48 cannot be cornpleted until the discharge requirements are
defined by the Salisbury POTW. This will occur during the RD.
9.2.5 COST
This criterion assesses the cost of an alternative in terms of totat present worth cost (PW). Totat
PW was calculated by combining the capital cost plus the PW of the annual O&M costs. Capital
cost includes engineering and design, mobilization, Site development, equipment. construction,
demobilization, utilities, and sampling/analyses. Operating costs were calculated for activities that
continue after completion of construction, such as routine operation and maintenance of treatment
equipment, and groundwater monitoring. The PW of an alternative is the amount of capital
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NAT1QW. STAACH' CIeI~ CcIIPAlt/9.fIeIIUC) SrTe
REOJRD CE DeasIOIc FOR 0PeIWu: UIIT 83
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TABLE 16 SUMMARY OF THE THRESHOLD CRITERIA EVALUATION FOR THE
ALTERNATIVES
:~:::j!:::,:I::::j':::jl:':::,::.I'_lj"i:,::,,:,j:::,:~,:',:i,i~::::,:: ilj..i::~,!:..:::I:..I:::li:':::::::I~:i~!i:::i.~'I_:I::i:I'::~I~i:::::I!:'::i::I::i;j,i:::: ::::,:811"1111.::;:"
GWP1/GWL1: No Action Does not eliminate any exposure Not in compliance
pathways or reduce the level of risk.
GWP2IGWL2: Long Term Does not eliminate any exposure Not in compliance
Mon~oring; Fence Portion of pathways, reduces potential risk of
Northeast Tributary exposure to contaminated surface
water/sediment by fencing stream.
Contamination would continue to
discharge into Northeast Trbutary.
GWP3/GWL3: Institutional Controls; Potential off.site contaminant migration Not in compliance
Long Term Monitoring; Fence "'ould not be eliminated. Institutional
Portion of Northeast Tributary controls would eliminate risk posed by
using contaminated groundwater as
potable water. Contamination would
continue to discharge into Northeast
Tributary.
GWP4A1GWL4A: Groundwater Off.site contaminant migration would be In compliance
Extraction; Treatment Via Air eliminated. Eliminates potential risk of
Stripping and Vapor-Phase ingestion, inhalation, and dermal
Adsorption; Discharge to POTW absorption. Eliminates contamination
entering Northeast Tributary.
GWP4B/GWL4B: Groundwater Off-site contaminant migration would be In compliance
Extraction; Treatment Via Air eliminated. Eliminates potential risk of
Stripping and Fume Incineration; ingestion, inhalation, and dermal
Discharge to POTW absorption. Eliminates contamination
entering Northeast Tributary.
SWISE.1: No Action Protective of human hea~h but may not No Federal or State
be protective of the environment. AAARs for contaminants
detected in stream.
SW/SE-2: Long-Term Monitoring Protective of human hedh but may not No Federal or State
be protective of the environment. AAARs for contaminants
detected in stream.
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NAnONAl STARCH & CIEMICAL CoMPANY SUPERFUND SItE
RECORD OF DECISION FOR OPEAAIIl£ UNIT 13
TABLE 17
ApPLICABLE OR RELEVANT AND ApPROPRIATE REQUIREMENTS
STANDARD REQUIREMENT,
CArTERIA, OR IIIrT ATION
CITATION
DESCflPnON
ApPUCABLElRELEVANT
AND ApPROPRIATE
CoMMENTS
.![i:_III:lllllili!1Itllillllllllll;f.ij;I!;~::
GROUNDWATER
Safe DrInIcing WBI.. Ad 42 U.S.C f 300 Establishes standards 'Of drinking wal.
NBl.ionaI Prinary DrinkIng 40 CFR Palt 141, SIiJparI B Establishes heath-based standards lor pIh.c
WBI..,Standards wat. systems maximlH11 conIamNnt levels
(MCls)
Maximum CoI8ninanllevei 40 CFR Part 141, Slilpart F Establishes drilking war. quality goals s81 aI
Goals levels o' no known or antic~ed adverse heath
effects
SUIFACE WATER
CINn WBI.. Ad 33 U.S.C. H 1311, 1313, 1317 Demes laws responsi)\e 'or protection o' the
lnIegrty 01 the naIion8 watetS
ArnIII8n W" QuaIiIy Cderia 40 CFR Part 131 Sels crieria 'or wBI.. quality based on toxicity to
(AWQC) aquBl.ic organisms and human health
*kInII",,- 0I8chIrge 40 CFR P8It 122, S~ C Defiles charge 11mb lor poIutants; use of best
Elminlllon System (NPDES) available tedlnology economically achievable 'or
toxic poIl~ants discharged to surface watetS
~ PrelN8lmlnl Progrwn 40 CFR Part 403 Sels 1mb lor clisc:hlqeto POTWs
W- QuaIiIy Managerned 40 CFR Part 130 Sels aileria for wBI.. quality based on toxicily to
"... (WQMP) aqUIIIc organisms and human heaIIh; disc:hlwge
must compfy _h EPA-approwd waMP
NoNes
NoNes
NoNes
YesNes
NoNes
YesMo
Yes&
HoIYes
The MCls lor organic and inorganic contaminMs
must be addressed as the groundwal. is a being
used a source lor drinking Waler
MClGs are appropriate allhis Site as I is a source of
drinking wat.
The AWQC lor organic and inorganic contarnNnts
are relevlri and appropriaIe
DIscharge from .acili1i8s must comply _h NPDES
regufalions
Prtlrealmed regulalions musl be l11li " ........
disdlarged 10 a POTW
Crileria avalable for wat. and Ish cons~; "
wast. water Is discharged to . waterway, . must be
In accord wth a waMP
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NAnONAl. STARCH & CIEUICAI. CoMPANY SUPEAFIJI) SllE
RECORO OF DECISION FOR OPEIWU UNIT 13
STANDARD REQUIREMENT,
CRrrERIA, OR llllrr ATION
CITATION
ApPLICABLE OR RELEVANT AND ApPROPRIATE REQUIREMENTS
DESCRIPTION
TABLE 17
AIR
Clean Air Ad
40 U.S.C. II 1851, 7409, 7411,
7412
40 CFR Part 50
National Prinary and
Secondary Ambient A'f QuaIiIy
SCandanla
Nation8l Emlsslona Standatds
for Hazardoua Nf PoIIuIanIa
(NESHAPa)
40 CFR PIIt 61
'1::I&I':il::~:I'::i':I.j:I.llil:I!::ij'i:I~:~111~~i:!j:::!~~j.:'\:~.:~'.i::liii1!:..:;:ji::j:I"'\::.:i.:
GROUNDWATER, SURFACE WATER, AlA
NoI1h
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NAnONAl. STARCH a CIEIlICAL CoMPANY SUPERFIJID SITE
RECORD OF DECISION FOR OPERAIIl£ UNIT 13
-76-
TABLE 18 SUMMARY OF PRIMARY BALANCING CRITERIA EVALUATION OF THE ALTERNATIVES
_~-'__~lij
GWP1/GWL1: No
Action
GWP2IGWl.2: Long-
TeRn Monimring;
Fence Portion of
Northeast Tributary
GWP3IGWl3:
Institutional Controls;
long-TeRn MonItonng;
Fence Portion of
Nor1heast Tributary
Does not meet MARs. Length of
service tJ1known (not permanent).
Ongoing monitoring of grooodwater
contaminant levels woWt be
conducted to assess contaminants
migration. ARARs are not met at
the Site. Length of service
unknown (not peRnanent). Fence
would reduce potential of exposure
to contaminated surface
water/sediment
Ongoing monitoring of groundwalPr
contaminant levels would be
conducted to assess contaminants
migration. ARMs are not met at
the SIIe. Effectiveness Is
depended on enforcement of
Institutional controls. Length of
service tI1known (not permanent).
Fence woWd reduce potential of
expoSt18 to contaminallld Stlface
water/sediment.
None, except natural None. None.
attenuation.
None, except natural None. None.
attenuation.
o
227
o
1,479
None, except natural
attenuation.
None.
None.
o
1,500
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NAnOlW. STARCH I CIEIlICAI. COIIPANY SUPERFIIIO SITE
RECORD OF DECISION FOR OPEIWILE UNIT 13
TABLE 18 SUMMARY OF PRIMARY BALANCING CRITERIA EVALUATION OF THE ALTERNATIVES
-..,--~r-
GWP4A1GWL4A:
Grotl1dwater
Exraction;Treatment
VIa AJr Stripping and
Vapor-Phase
Adsorption; Discharge
mPOTW
GWP4B1GWL4B:
GromcMater
Extraction; Treatment
VIa AJr Stripping and
FOO18 lnci1eration;
Discharge m POTW
SWISE.1: No ActIon
SWISE.2: Long-Term
Morimmg
Permanent remedy.
MARs are met.
Permanent remedy.
MARs are met.
I.hier curent conditions tunan
health may be protected but
possibly not the environment.
I.hier curent concitlons tunan
health may be protected but
possibly not the environment.
E~mlnates TMV 01
contaminants and potential
tor off-site migration.
Greatest degree 01 risk
reduction for ingestion,
Inhalation, and dennal
absorption.
E~minates mv 01
contaminants and potential
for off-site migration.
Greatest degree 01 risk
reduction for ingestion.
inhalation, and dennal
absorption.
Potential release 01 VOCs
during extraction well
installation and treatment
system operation. Noise
nuisance due to operation
01 drilling equipment.
Potential release 01 VOCs
during extraction well
installation and treatment
system operation. Noise
nuisance due to operation
01 drilling equipment.
Design 01 extraction,
treatment, discharge, and
monitoring systems. AJr
stripping 0' VOCs to meet
POTW pretreatment
requirements. Treatment 0'
air stripping off-gases will
be required during start-up.
Design 0' extraction.
treatment, discharge, and
monitoring systems. AJr
stripping 0' VOCs to meet
POTW pretreatment
requirements. Treatment 01
air stripping off-gases will
be required ckling start-up.
12 months to design
6 months to construct
12 months to design
6 months to construct
5.792
5,270
Would increase mobility 0' None. None. None. 151
contaminants. however,
through volatilization toxicity
and volume 0'
contaminants in the water
column would be reduced.
Would Increase mobility 0' None. None. None. 867
contaminants, however.
hough volatilization toxicity
and volume 0'
contaminants In the water
column would be reduced.
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NA'TIOIW. STAAOI . CIEW~ CoMPNI'r ~ Sm:
REcoRD r:6 DeasoN FOR 0Pswu UIIT 83
-78-
required to be deposited at the present time at a given interest rate to yield the total amount
necessary to pay for initial construction costs and future expenditures, including O&M and future
replacement of capital equipment.
More detailed information on the development of the total present worth costs for each alternative
can be found in Section 8.
Alternative GWP 1/GWL 1
No Action
$ 227,000
Alternative GWP2IGWL2
Long-Term Monitoring, Fence Portion of
Northeast Tributary:
$1,479,000
Alternative GWP3/GWL3
Institutional Controls, Long-Term Monitoring,
Fence Portion of Northeast Tributary:
$1,500,000
Alternative GWP4A1GWL4A Groundwater Extraction/Air Stripping!
Vapor-Phase Carbon AdsorptionlPOTW Discharge: $5,792,000
Alternative GWP4B/GWL4B Groundwater Extraction/Air Stripping!
Fume IncinerationlPOTW Discharge:
$5,270,000
Alternative SW/SE-1
No hdion
$ 151,000
$ 867,000
Alternative SW/SE-2
Long- Term Monitoring
9.3 MODIFYING CRrrERIA
State and community acceptance are modifying criteria that shall be considered in selecting the
remedial action.
9.3.1 STATE OF NORTH CAROLINA ACCEPTANCE
The State of North Carolina has reviewed and provided EPA with comments on the reports and
data from the AI and the FS. NCDEHNA has also reviewed the Proposed Plan and EPA's
preferred alternative and conditionally concurs with the selected rernedy as described in Section
10. The State's correspondence providing conditional concurrence, along with the specifio
conditions, and the Agency's response to the stipulated conditions can be found in Appendix A.
9.3.2 COMMUNITY ACCEPTANCE
The Proposed Plan Fact Sheet was distributed to interested residents, to local newspapers and
radio and TV stations, and to local, State, and Federal officials on July 15, 1993. The Proposed
Plan public meeting was held in the evening of August 3, 1993. The public comment period on
the Proposed Plan began July 19, 1993 and closed on September 16, 1993.
Written comments were received from the City of Salisbury and NSCC during the public comment
period. The questions asked during the August 3, 1993 public meeting and the Agency's
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NA11ONAI. STARaI & CHalICAI. COMPANY SUPeRRJIID SITE
REooRo OF DeaSlON FOR OPERABLE UIGT 13
-79-
response to the written comments are summarized in the Responsiveness Summary, Appendix
A. Since no input was received from the community at large, it is infeasible to assess the
community's acceptance of the proposed remedy.
10.0 DESCRIPTION OF THE SELECTED REMEDY
As stated previously, the soil remediation alternative will be addressed in au #4. Alternative
GWP3/GWL3 and GWP4A1GWL4A was selected for groundwater and SW/SE-2 for the surface
water/sediment in the Northeast Tributary. Briefly, the selected remedy for this Site is:
. Implement a deed restriction as the institutional control.
. Long-term monitoring of the groundwater and the surface water/sediment in the Northeast
Tributary.
. Design and implementation of a groundwater remediation system. The selected groundwater
remediation alternative consists of a groundwater extraction system consisting of extraction
wells, an air stripping process to remove the vacs, control of emissions from the air stripper
to the atmosphere through vapor-phase carbon adsorption filters, and combining the effluent
with the treated groundwater from au #1 and the facility's operation effluent to be discharged
to the City of Salisbury POTW system.
. Delineate the vertical extent of groundwater contamination in the bedrock.
. More accurately evaluate the direction and speed of the flow of groundwater in the bedrock.
. . Conduct a review of the existing groundwater monitoring system to insure proper monitoring
of both groundwater quality and groundwater flow so that the effectiveness of the groundwater
extraction system can be evaluated. Additional monitoring wells and/or piezometers will be
added to mitigate any deficiencies.
. Alternative GWP3/GWL3 also includes fencing a portion of the Northeast Tributary. However,
since the groundwater extraction system will reduce and then eliminate contamination
migrating into the Northeast Tributary, it will not be necessary to install this fence. This
condition will be evaluated in the 5 year CERCLA review.
This remedy will reduce the levels of contamination in the groundwater to below their Federal
MCLs and State groundwater quality standards.
10.1 PERFORMANCE STANDARDS TO BE ATTAINED
Table 17 lists the action-specific, chemical-specific, and location-specific Site specific ARARs.
Performance standards include any applicable or relevant and appropriate standards/
requirements, cleanup levels, or remediation levels to be achieved by the remedial action. The
surface water and groundwater performance standards to be met/attained by the NSCC au #3
RA are listed in Table 19.
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NATIONAl STARCH & CHEMICAl. COMpANY 5uPeRRJND SITE
RECORD OF OeaSlON FOR OPEIWILE UNIT 83
-80-
Table 19 provides the remediation goals to be achieved at this Site along with the range and
frequency of detection for the listed contaminants. This table also lists the risk level associated
with each remediation goal. These risks are based on the reasonable maximum exposure (RME)
levels and summarizes the information provided in Tables 8, 9, 10, 11, 12, and 13.
10.2 GROUNDWATER REMEDIATION
The groundwater remediation altematives selected for the OU #3 at the NSCC Site are
GWP3/GWL3 and GWP4A1GWL4A - Institutional Controls, Long-term Monitoring, Groundwater
Extraction and Physical Treatment (Air Stripping) with Control of Air Emissions Via Vapor-Phase
Carbon Adsorption Filters, and Discharge to POTW. A description of the selected remedial
altemative follows.
The contaminated aquifer will be remediated by removal of contaminated groundwater through
extraction wells until the performance standards specified in Table 19 are achieved. Figures 3,
4, and 7 delineates the estimated periphery of the plumes emanating from OU #3. The extracted
groundwater from Area 2 and the lagoon area will be combined for treatment. Following
treatment of the extracted groundwater, the groundwater will be discharged into the sewer system
along with the rest of the NSCC influent to the City of Salisbury POTW.
It is anticipated that four (4) extracting wells, two (2) installed in the saprolite and 2 into the .
bedrock, downgradient of Area 2 and six (6) extraction wells, three (3) installed in the saprolite
and 3 into the bedrock, downgradient of the lagoon area will be required. The Area 2 bedrock
and saprolite extraction wells would have an estimated combined flow of 15 gallons per minute
(gpm) and 10 gpm, respectively. The lagoon area bedrock and saprolite extraction wells will have
an estimated combined flow of 6 gpm and 30 gpm, respectively. At these pumping rates, it is
anticipated that these wells will achieve and maintain a sufficient drawdown in the underlying
aquifer to contain and remove the plumes of contamination. The extraction wells will be located
within and near the sources of contamination. The extracted groundwater will be treated in an
above-ground, on-site air stripper. The actual number, placement, pumping rate of each
extraction well, the size of the air stripping unit, and the size of the vapor-phase activated carbon
adsorption units will be determined in the RD. The air stripper will be designed to achieve the
pretreatment requirements which will be determined by the City of Salisbury POTW. The only
anticipated by-product to be generated by the groundwater treatment process described above
is spent activated carbon. The activated carbon may be regenerated, destroyed, or disposed of
in an appropriately regulated landfill. The most cost effective option for dealing with the spent
activated carbon will be implemented. The estimated volume of groundwater adversely impacted
by past Site activities is 131 million gallons.
Groundwater contamination may be especially persistent in the immediate vicinity of the
contaminants' source where concentrations are relatively high. The ability to achieve cleanup
goals at all points throughout the area of attainment, or plume, cannot be determined until the
extraction system has been implemented, modified as necessary, and plume response monitored
over time. If the selected remedy cannot meet the specified performance standards, at any or
all of the monitoring points during implementation, the contingency measures and goals described
in this section may replace the selected remedy and goals for these portions of the plume.
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NATIONAl STARCH & CIEUICAl CoUPANY SUPERFlMI SITe
RECORD OF DECISION FOR OPeRA8l£ UNIT 13
-81-
TABLE 1 9 PERFORMANCE STANDARDS AND CORRESPONDING RISKS FOR OU #3
PERFORMANCE STANDARDS (CLEANUP GOALS) CORRESPONDING RISK LEVELS
CHEMICAL OF RANGE AND
CONCERN FREOUENCY ( ) PERFORMANCE POINT OF BASIS OF CHEMICAL -SPECIFIC RME RISK
OF DETECTION STANDARD COMPLIANCE STANDARD CANCER(a) NON-CANCER( a)
(~g/l) (1-19/1)
GROUNDWATER
Ac:e~ne 9"',200 (15) 700 State NA 1.0
Bis(2 -Chioroelhyl)elher 13-32 (2) 5 CROUState(b) 1E-4 NA
Chlorofonn 7 -8.900 (2) 1 CROUState(b) 2E-7 NA
1,2-Dictioroet1ane , ~.OOO (30) , The Entire CROUStale(b) 2E-6 NA
1," ~ 1 .14 (3) 7 MCUSIaI8 1E-4 NA
Plume of
1,2.Dichloroethene (dsllrans) 1-200 (4) 70 MCUSIaIB NA 0.2
1,2-Dichloropropane 5 (1) 1 Contaminated CROUState(b) 2E-6 NA
Methytene Chloride 1.160 (5) 5 MCUStale 1E-6 NA
TetracNoroethene 1-7 (4) 1 Groundwater CRQUState(b) 1E-6 0.003
1,1,2. Trichloroethane 1-5 (10) 5 CROUState(b) 2E-6 0.006
Trichloroethene 1.5 (4) 2.8 State 9E-7 0.01
'lilyl ChlorIde 1-120 (8) 1 CROUState(b) 5E.5 NA
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NA11ONA1. STARCH & CIEMICAl COMPANY SUPERFIJjD SITE
RECORD OF DECISION FOR OPERASlE UNIT 13
-82-
TABLE 19 PERFORMANCE STANDARDS AND CORRESPONDING RISKS FOR au #3
PERFORMANCE STANDARDS (CLEANUP GOALS)
CORRESPONDING RISK LEVELS
CHEMICAL OF
CONCERN
RANGE AND
FREQUENCY ( )
OF DETECTION
(~g/l)
PERFORMANCE
STANDARD
(~gll)
POINT OF
COMPLIANCE
BASIS OF
STANDARD
CHEMICAL-SPECIFIC RME RISK'
Bis(2-ethyhlxyl)phthalate
8 (1)
5
11.1811:_)_IJ,I'il:llli~"II[jll:::lJi:l:il:lj1iIJ:jl:ljl:f:I1111111JJII::\i::11111:i!:II.:.:II1I:1::il
1111_111Iilllllilll11iIIIIIII111111111111'1111111:111itllil:111111111Iil111iltllillll:lil:i:II::i111:i;\111:il:11111iill,il:il,\::iilli1,llri;:ii:;,II:;,::::i,::ii::::II:I.:::;,:II:il:I:::i:::I:i::1
Antimony 2-30 (3) 6 MCl NA 0.4
Chromium 12.9-59.6 (6) 50 Slate NA 0.3
Manganese 28-12,000 (14) 50 Slate NA 0.3
Thalium 1-3 (2) 2 MCL NA 0.9
Zinc 22~,410,ooo (4) 2,100 Slate NA 0.2
SURFACE WATER
1,2-Dlc:hIoroehne
2"',400 (19)
2,000
Northeast T riIUI;uy
on NSCC Properly
EPA, Region IV Chronic
Screening Value
NA
NA
~gll -- micrograms per liter
MCL -- Maximum Concentration Limit as Specified In the Safe Drinking Water Act
(a) -- The risk levels are based on a 2 liter dally consumption rate by a 70 kilogram Individual.
CRQUState{b} -- Where the Maximum Allowable Concentration Of A Substance Is Less Than The Limit Of Detectabillty
. (NCAC 15-2L.0202(b)(1» and where CRQL Is the Contract Required Quantitation Limit
State -- State Groundwater Quality Standards (NCAC 15-2L.0202)
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NAtDIAL STARCH! CielCAI. CaJIINtr ~ SITE
REaJID r:s DEasoN Fa! 0PswI.E UIIT 13
-83-
The goal of this remedial action is to restore the groundwater to its beneficial use, as defined in
Section 7.4. Based on information obtained during the RI, and the analysis of all of the remedial
alternatives, EPA and the State of North Carolina believe that the selected remedy may be able
to achieve this goal.
Such contingency measures will, at a minimum, prevent further migration of the plume and
include a combination of containment technologies and institutional controls. These measures
are considered to be protective of human health and the environment, and are technically
practicable under the corresponding circumstances.
The selected remedy will include groundwater extraction for an estimated period of 30 years,
during which time the system's performance will be carefully monitored on a regular basis and
adjusted as warranted by the performance data collected during operation. Modifications may
include any or all of the followings:
a) at individual wells where cleanup goals have been attained, pumping may be
discontinued;
b) alternating pumping at wells to eliminate stagnation points
c) pulse pumping to allow aauifer equilibration and encourage adsorbed contaminants to
partition into groundwater;
d) installation of additional extraction wells to facilitate or accelerate cleanup of the
contaminant plume.
To ensure that cleanup continues to be maintained, the aquifer will be monitored at those wells
where pumping has ceased on an occurrence of every 2 years following discontinuation of
groundwater extraction.
If it is determined, on the basis of the preceding criteria and the system performance data, that
certain portions of the aquifer cannot be restored to their beneficial use, all of the following
measures involving long-term management may occur, for an indefinite period of time, as a
modification of the existing system:
a) engineering controls such as physical barriers, or long-term gradient control provided by
low level pumping, as contaminant measure;
b) chemical-specific ARARs may be waived for the cleanup of those portions of the aquifer
based on the technical impracticability of achieving further contaminant reduction;
c) institutional controls may be provided/maintained to restrict access to those portions of the
aquifer which remain above remediation goals;
d) continued monitoring of specified wells; and/or
e) periodic reevaluation of remedial technologies for groundwater restoration.
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NA'IIOM. STNOII CIeIICM. eo.l«Y ~ sm:
REccRo OF Dea9CII FOR 0PBIAaE UIIT «3
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The decision to invoke any or all of these measures may be made during a periodic review of the
remedial action, which will occur at5 year intervals in accordance with CERCLA Section 121(c).
The RA shall comply with all ARARs listed in Table 17. The presence of contamination in the
groundwater will require deed restrictions to document their presence and could limit future use
of the area known to be affected by the contaminated groundwater.
10.3 NORTHEAST TRIBUTARY SURFACE WATER/SEDIMENT REMEDIATION
It is anticipated that the groundwater remediation alternative described above will initially reduce
and then eliminate contamination in the Northeast Tributary as the source of this contamination
is the contaminated groundwater discharging into the stream. Alternative SW/SE-2 requires long-
term monitoring of the water column and sediment to insure that the groundwater remediation is
reducing the levels of contamination in the Northeast Tributary. .
Initially, each annual sampling effort will collect paired surface water and sediment samples at a
minimum of four (4) sampling locations. These samples shall be analyzed for TCl VOCs. After
the groundwater extraction system becomes operational and the levels of contamination in the
Northeast Tributary obtain the performance standards specified in Table 19 for two consecutive
sampling events, the number of sa::1pling points and the sampling frequency may be reduced.
10.4 MONITOR EXISTING CONDmONS/ADDmONAL DATA REQUIREMENTS
In addition to the work described above, this ROD and the RD will also have to address a number
of data gaps.
Since the RI was not able to completely delineate the extent of the groundwater contamination
in the bedrock zone of the aquifer, additional monitoring wells will need to be installed during the
RD. It is anticipated that at least two (2) bedrock monitoring wells are needed to better portray
the vertical extent of contamination as well as delineate the depth to which bedrock is fractured.
To determine to what depth the bedrock is fractured, bedrock cores will need to be collected. The
analytical data generated from the samples collected from these bedrock wells should provide
sufficient information to determine if contaminants have migrated to this depth. The pI.acement
of these and any other additional monitoring wells will be made after a review and evaluation of
the existing groundwater monitoring system. This review is to insure that the groundwater
monitoring system will provide adequate information to assess the long-term quality of the
groundwater and to demonstrate the effectiveness of the groundwater extraction system. This
review effort may also require the need for additional groundwater modeling and aquifer testing.
If a contaminant is found above its groundwater remediation standard specified in Table 19 in the
deeper regions of the bedrock, then the groundwater extraction system shall be extended to
include this lower region of the bedrock zone of the aquifer and all the requirements specified in
Sections 10.0, 10.1 and 10.2 of this ROD will apply.
In order to help establish a broader data base on groundwater quality additional groundwater
samples will be collected and analyzed. Below are listed the wells to be sampled, how frequently
these wells are to be sampled, and the chemical analyses to be performed on each groundwater
sample collected. This sampling effort will continue until the groundwater remediation system is
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NA11CIIW. ST~. CIeIICoIl CalF., 5uIBfuI) SITE
REroRD a: DeaSDI FeR 0PswIE UIIT t3
-85-
functional and the monitoring procedures specified in the Operation and Maintenance Manual are
implemented.
Analytical
Monitoring Well Sampling Samples Are To Procedure
To Be Sampled Frequency Be Analyzed For To Be Used
Saorollte wells
NS-13 Annually VOCs, TAL metals EPA Methods 8240 + 6010
NS-14 Annually VOCs EPA Method 8240
NS-33 Annually VOCs EPA Method 8240
NS-35 . Biannually VOCs, TAL metals EPA Methods 8240 + 6010
NS-37 Annually VOCs EPA Method 8240
NS-39 Annually VOCs EPA Method 8240
NS-42 Biannually VOCs, TAL metals EPA Methods 8240 + 6010
NS-43 Annually VOCs EPA Method 8240
Bedrock Wells
NS-34 Annually VOCs EPA Method 8240
NS-36 Biannually VOCs, TAL metals EPA Methods 8240 + 6010
NS-38 Annually VOCs EPA Method 8240
NS-40 Biannually VOCs, TAL metals EPA Methods 8240 + 6010
NS-41 Annually VOCs EPA Method 8240
NS-44 Annually VOCs EPA Method 8240
10.5 COST
The total present worth costs for the selected alternatives is
Alternative GWP3/GWl3:
Alternative GWP4AJGWl4A:
Alternative SW/SE-2:
TOTAL PRESENT WORTH COST
$ 1,500,000
$ 5,792,000
$ 867.000
$ 8,159,000
The break down of this cost is specified below.
The present worth cost components 01 the institutional controls, long-term monitoring,
groundwater extraction, air stripping, emissions control of off-gas via vapor-phase activated
carbon filtration, and discharging to the local POTW are:
TOTAL CONSTRUCTION COSTS
TOTAL PW O&M COSTS (at annual PW O&M Costs of $878.000)
TOTAL PRESENT WORTH COST
$1,635,000
$6.524.000
$8,159,000
11.0 STATUTORY DETERMINATION
Based on available information, the selected remedy satisfies the requirements 01 Section 121
01 CERCLA, as amended by SARA, and the NCP. The remedy provides protection of human
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NA'IIONIol STAACH . CISlICAI. CoIIPNN SUPeiIRN) SrTt
ReQ)RD CE OEaSlON Fa! 0PeMai UIIT «3
-86-
health and the environment, is cost-effective, utilizes permanent solutions to the maximum extent
practicable, and satisfies the statutory preference for remedies involving treatment technologies.
11.1 PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The selected remedy will permanenUy treat the groundwater. Dermal, ingestion, and inhalation
contact with Site contaminants will be eliminated and risks posed by continued groundwater
contamination will be abated.
11.2 COMPLIANCE WITH ARARS
The selected remedy will be designed to meet all Federal or more stringent State environmental
laws. A complete list of the ARARs which are to be attained is included in Table 17. No waivers
of Federal or State requirements are anticipated for OU 13.
11.3 COST-EFFECTIVENESS
The selected groundwater remediation technologies are more cost-effective than the other
acceptable alternatives considered. The selected remedy will provide greater benefit for the cost
because it permanently removes the contaminants from the impacted aquifer.
11.4 UTILIZATION OF PERMANENT SOLUTIONS AND ALTERNATIVE TREATMENT
TECHNOLOGIES OR RESOURCE TECHNOLOGIES TO THE MAXIMUM EXTENT
PRACTICABLE
The selected remedy represents the maximum extent to which permanent solutions and treatment
can be practicably utilized for this action. Of the alternatives that are protective of human health
and the environment and comply with ARARs, EPA and the State have determined that the
selected remedy provides the best balance of trade-offs in terms of: long-term effectiveness and
permanence; reduction in mobility, toxicity, or volume achieved through treatment; short-term
effectiveness, implementability, and cost; State and community acceptance; and the statutory
preference for treatment as a principal element.
11.5 PREFERENCE FOR TREATMENT AS A PRINCIPAL ELEMENT
The preference for the treatment of contaminated groundwater is satisfied by the use of the
groundwater extraction system, the air stripper to remove volatile contaminants from the
groundwater, and control of the air stripper off-gas via vapor-phase activated carbon adsorption
at the Site. Further treatment of the discharged groundwater will be achieved at the POlW. The
principal threats at the Site will be eliminated by use of these treatment technologies.
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REa:IRc (E 0e0aaN FOR ()Igwu UIIT 83
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12.0 SIGNIFICANT CHANGES
CERCLA Section 117(b) requires an explanation of any significant changes from the preferred
alternative originally presented in the Proposed Plan (Appendix B). Below are the specific
changes made in the ROD as well as the supporting rationale for making those changes. The
Proposed Plan was disseminated to the public on July 15, 1993.
Alternative GWP3/GWL3 included installing a fence around a portion of the Northeast Tributary
as it assumed that no remediation of the groundwater would occur. However. the selected
remedy does. call for the implementation of an active groundwater extraction system. The
groundwater extraction system will reduce and then eliminate the contaminants entering into the
surface water and sediment of the Northeast Tributary, thereby eliminating the need for this fence.
This is the reason why the installation of the fence around a portion of the Northeast Tributary has
been excluded from the selected remedy as described in Section 10.
The Proposed Plan reported the total present worth costs for Alternatives GWP4A, GWL4A,
GWP4B, and GWL4B to be $2,222,000, $3.570,000, $2,274,000. and $2,996,000. respectively.
These costs, obtained from the June 21, 1993 OU #3 FS report. were based on obtaining the
cleanup goals at the point of compliance specified in said document. The FS proposed obtaining
a groundwater cleanup goal of 5.0 IlQII for 1 ,2-DCA at the periphery of the plume. However, the
use of 5.0 IlQII as a cleanup goal for 1.2-DCA and the selection of the periphery of the plume at
point of compliance are in error. Tne most stringent promulgated cfeanup level for 1,2-DCA can
be found in the State's groundwater quality standards and is described in Section 10.1 as 1.0 1lQ11.
The point of compliance, as described in Section 8.1. is throughout the entire plume. By
changing these two conditions. the estimated remediation timeframe is lengthened which results
in a different O&M cost for Alternatives GWP4A, GWL4A, GWP4B. and GWL4B. The total
present worth costs for Alternative GWP4A1GWL4A becomes approximately $107,000 less than
the total present worth costs for Alternative GWP4B/GWL4B: Since both alternatives achieve the
same degree of protection and treatment, Alternative GWP4A1GWL4A is selected because it is
more cost effective. Also, refer to Comment #9 in the Responsiveness Summary (Appendix C).
-------
APPENDIX A
CONCURRENCE LETTER FROM THE STATE OF NORTH CAROLINA
AND RESPONSE FROM THE AGENCY
..
-------
--- --
State of North Carolina
Department of Environment, Health, and Natural Resources
512 Nonh Salisbury Street . Raleigh, North Carolina 27604
: ~
: "t
- ',' a( Solid Waste ~...~aIt
"j ,:1 1):, . . 919.7.&ZI01
!. ;lJ i " ;~
,.:,r ..~ . .(, " .
ojl' : t ~ ~ ,';. ~
'J' I ~ I..
" "j~; :1" 'I l ,.. 23, 1993
~;#! ' ":'.1\
Jonathan B. ~, Secretary
James B. Hunt, Jr., Governor
. '.' ..
,":
."- ..
..;/':~ :...;;
-.:'181..:" ,
.!. .". .
-.:,. t. .
-" Mr. Curt FeJm; 0Def '
NC Remedial Section
u.s. EPA Region IV
34S Courtland Street, N.E.
Atlanta, GA 30365
2.
.. -........-- .'..
Subj: Conditional Concurrence with the Record of Decision
National Starch and Chemi(od} Company NPL Site
Salisbury, Rowan County, NC
Dear Mr. Fehn:
Tbe Division of Solid Waste Management (DSWM) has completed review of the
attached Draft Record of Decision and concurs with the selected remedy subject to the
fonowing conditions.
1.
The NC Groundwater Standard for trans 1,2-did1loroethene is 70 u&/l DOt 100 ui/l
as shown in the Draft ROD. The Performance Standard for this contaminAnt in
Table 21 (page 109 of the Draft ROD) as well as the groundwater standard data in
Table 4 (Paae 24 of the Draft ROD) should be corrected accordiDslY.
New State Groundwater Standards (15A NCAC 2L .0202) have been approved by the
NC Environmental Management Commi~c:ion and the Rules Review Committee.
The new standards will take effect October 1, 1993. For acetone the new standard
is 700 ug/1. and for xylene the new standard is 530 u&/L These new standards are
based on the latest health information and represent the best science. Funhermore.
these are the smnmu-ds that have been approved aDd will be in effect duri.us the
remedial ef[ons. Therefore. the Division of Solid Waste Management requests that
the performance standards presently in the Draft ROD be modified to reflect the
new NC Groundwater Standards.
PO 8011 7761r7. 1YIe1gh. Nonn CarolIna 27611-7687 lCIr,lhoM 919-733-4984 Fa 19I9-1UCSI3
An Eq....1 0pp0mm1Cy AfftrmaItw ~ ~
-------
-_. -~ -- ..._~-
-....., -." -' '- -- - .
c..'-' '-c..-
Mr. CUrt Febn
22 September 1993
Pqe2
3.
DSWM c:oncurrence on this Record of Decision and the selected remedy for the site
is based solely on the information contained in the attached Draft Record of
Decision. Should DSWM receive new or additional infonnation which sipific:antly
affects the conclusions or remedy selection contained in the Record of Decision. it
may modify or withdraw this concurrence with wrincn notice to EPA Reaion IV.
DSWM concurrence on this Record of Decision in no way binds the State to concur
in future decisions or commitS the State to participate, financially or otherwise, in the
clean up of the site. The State reserves the riaht to review, comment, and make
independent assessmentS of all future work re1atina 10 this site.
4.
# ~....~..
..... --- -.. _.:
.---.;.... ...' . ...._..
The DSWM appreciates the opportunity to comment on the Revised Draft Record of
Dec:ision for the subject site. and we look forward to workins with EPA on the final remedy.
If you have any questions concerning these comments please contact Bruce Nicholson or me
at (919)733-2801.
Sincerely,
~
Jack Butler, PE
Environmental EDgineeriDg Supervisor
Superfund Section
bin\let\~n
cc: Michael Kelly
Broce Nicholson
Jon Bomholm
Attachment
-------
..,.to sr.,...
.,) . r
~... ,~~
$ ~..H t:
~~~
'\, ,t
,.., '""01\"
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION IV
345 COURTLAND STREET. N.E.
ATLANTA. GEORGIA 30365
SEP 2 4 1993
4WD-NCRS
Mr. Jack Butler, PE
Environmental Engineering Supervisor
Superfund Section
Division of Solid Waste Management
North Carolina Department of Environment,
Health, and Natural Resources
P.O. Box 27687
Raleigh, North Carolina 27611-7687
RE:
Conditional Concurrence on Operable Unit '3 Record of Decision for the
National Starch & Chemical Company Superfund Site from North Carolina
Division of Solid Waste Management
Dear Hr. Butler:
EPA-Region IV appreciates the Dj"ision of Solid waste Management, North Carolina
Department of Environment, Health, and Natural Resources's concurrence on the
Record of Decision (ROD) for Operable Unit 13 at the National Starch & Chemical
company Superfund site located in Salisbury, North Carolina. For the record, EPA
would like to respond to your september 23, 1993 conditional concurrence letter.
Your letter, along with this response, will be included in Appendix A of the ROD.
These letters should stand as official documentation that EPA-Region IV and
Division of Solid Waste Management have agreed on the preferred alternatives at
this point in time.
For your information, the Agency has incorporated the States's groundwater
standard of 70.0 s.u;/l for trans-l,2-dichloroethene in all the appropriate tables.
The Agency has also incorporated 700 ~/l as the performance standard for acetone
in the ROD.
Please contact me at
regarding this matter.
(404)3457-7791 if you have any questions or comments
Sincerely yours,
jrK6dwJ~
Jon K. Bornholm
Remedial Project Manager
cc:
Curt Pehn, EPA
Bruce Nicholson, NCDEHNR
Printed on Recycled Paper
-------
APPENDIX B
PROPOSED PLAN FACT SHEET
-
-------
~Ut"~Ht-UNU I"nvr-v.;)c:u r-I.~N r~\'" I ;:)m:~ I
""-1 "'
~)
Region 4
GROUNDWATER REMEDIATION FOR OPERABLE UNIT ~; FOR THE
NATIONAL STARCH & CHEMICAL COMPANY SUPERFUND SITE
Salisbury, Rowan County, North Carolina
July 1993
ItmlODUCT1ON
This Proposed Plan identifies the preferred options for addressing the contaminated groundwB18r and surface water/sedlnent
associated with Operable Unit t3 at the National Starch & Chemical Company SuperMd Site WI Salisb6y, North Carolina. The
tenn .Operable Unit" is used when i1dividuaI actions are taken as a part of an overall sits c:Ieanup. A runber of operable ants
can be used in the course of a site~. (Tenns iI bold face print are defined iI a gossary located at the end 0' ttis
publication.) This document has been prepared and is being issued by tie U.S. EtMrotmentai Protection AQ8rq (EPA), the lead
Agerq for ?ite activities, and the Nor1h Carolina Department of Environment, Health and Nata.nl ReSOtlt8S (NCOEHNR), hi
support agency. EPA, in c:onsUtation.;1h NCOEHNR, direc:tBd and oversaw h RemedllllnvlStlgltlOn and FtIsIbiIIty Study,
and will select a remedy for Operable Unit 13 only after the public comment period has ended and all information submill8d kI EP A
during this time has been reviewed and considered. .
EPA is issuing this Proposed Plan as part of its public participation responsibiities in accordance with Section 117(a) of tie
Camprehenslve Environmental Response, Compensation, and Uabnlty Act (CERCLA), also known as SuperMd.
This document Silnmarizes infoImaiion that is explained in greater detai in the Rem8(iaJ Investigation Report. tie Feasibiity SUiy
Report. and other documents contand in the information RepasitoryfAchlnlstrltlvl RecanI for Ihis SitB. EPA and h Sta8
encourage the public to review h58 doaI'nen:: kI better understand I1e Sits and h ~ activities Ihat have be81
conducted. The Adminisntive Record is available lor public reviaw locally at tie Rowan Public Library at 201 West FISher Stre8I.
Salisbury, Hartt Carolina.
EP A. in consultation with HCOEHNR, may modify the preferred alternative 01' seIec:t another re~ actiOn presented in this Plan
and the Remedial Investigation and tie Feasibiity Study Reports based on new i1fonnation ard'or public comme(1ts. Therefore,
the public is encouraged to review and comment on all alternatives identified here.
A fourth Operable Um ';11 be developed kI address the contaminated soils and sowce of comamination at tie Site in the near
fuUJre.
1. Includes a brief badqMd of the Sit8 and .. principal
findings of Operable Unit 13 Sill RamedaI
Investigation;
2. Presents h remecIaI (cIeaII.Ip) aII8mati\l8S a the SitB
considered by EPA;
3. Outlines the CI1IIriI used by EPA to recommend a
remedial alttluid.e far use at" Site;
.c. Provides a sunmalY of .. analysis of ItIe remecIaI
alternatives;
5. Presents EPA's ratianaIe for ill preIminary seIec:tian of
the prefefred remedal aIiImaMs; and
6. ~ the opporUVtes a tie sU* to commert on
the remedal aItBmaMs.
THIS PROPOSED PLAN
PUBLIC MEETING:
DATE: August 3, 1993
LOCATION: Agrtculural Extension Center
2727 Old concord RoIcI
Salisbury, NoIth Carolina
7:00 PM. 1:00 PII
TIME:
PUBLIC COMMENT PERIOD:
July 19, 1993 . August 17, 1993
-------
T
N
Figure 1
250 750
GRAPHIC SCALE.
-------
SITE BACKGROUND
The National Start* & Chemical Company (NSCC) fadty
occupies 465 acres on Cedar Springs Road on the outskirts
of Salisbury, North Caroina (refer to Fgure f). Presently,
land use immediately adjacent to the Site is a mixture of
residential and industrial developments. East and south of
the Site are industrial parks consisting primarily of ight
industrial operations. The west and north sides of the NSCC
property are bordered by residential developments. Refer to
the Figure 2 for Site location.
A surface stream, referred to as the Northeast Tributary,
crosses the NSCC property parallel to Cedar Spring Road
and passes witwi 50 yards of the manufacturing area of tw
facility (refer to Figure 2). Surface water runoff from the
eastern side of the facfflty discharges «to this tributary. The
focus of Ihe Operable Unit 13 Remedial Investigation was to
determine the source, nature, and extent of Vie
contamination entering this stream.
Pnmarily, NSCC manufactures textile-irishing chemicals
and custom specialty chemicals. Volatile and seml-voHtlle
organic chemicals are used in the production process
along with ackfc and akaline solutions. Acick and alkaline
solutions are also used in the cleaning processes. The
waste stream from the manufacturing process includes wash
and rinse solutions.
*
1
-..iJ
Operable Unit «3 tocused on tw areas of the iaciity referred
to as Area 2 and the wastewater treatment lagoons (ret* to
figure 3). Area 2 consists of the following operations: Area
2 Reactor Room, tw Tank Room, Raw Material Buk
Storage, and the Warehouse. The lagoon area includes
three lagoons. A fourth lagoon was instated in 1992 tor
pretreatment of contaminated groundwater as part of tie
Operable Unit 11 Remecial Action (RA).
As the result of Snding contaminants in groundwater and in
the surface water/sediment of the Northeast Tributary, the
original scope of work specified in tie initial Remedwl
IrrvestigatkxVFeasfcity Study Work Plan nas been
expanded twice. The first Remedal Investigation and
Feasibility Study resulted in tw Irst Record of Decision
(ROD) to be issued by the Agency on September 30,1988
for the NSCC Superfund site. The fixings of Operable Unit
f2 Remedial hvestjgatkxVFeasfciWy Study led to the second
Record of Decision, rendered by the Agency on September
30,1990. As in Operable Unt §1 and Operable Unit«, the
work performed tor Operable Unit 19 is being performed by
National Starch & Chemical Corporation, tie Potentially
Responsible Party (PRP). The engineering contractor hired
by tie PRP to conduct Operable Unit *3 work is fT
Corporation.
The NSCC site was proposed for inclusion on the
National Priori flee list in April 1985 and finalized
on the to in October 1989. The Site had a
Hazardous Ranking System score of 46.51. Only
Sites with a Hazardous Ranking System score of
28.S or higher are eligible to be placed on tw
National Priorities List
SCOPE AND ROLE OF OPERABLE UWT
WTTHM SHE STRATEGY
As witi many Superfund sites, the NSCC site is
complex. Consequently, EPA drvried the work rto
three manageable componente caled Openbte
Units (OU). These operable units are:
OU-1 Groundwater in western portion of the
NSCC property
OU-2- Trench Area soils and surface
water/sediments in the Northeast
Tributary
OU-3 Groundwater/surtace water/sedtoents in
the areas of Area 2, the tegoont, and tw
Northeast Tributary
-------
RESULTS Of THE REMEDIAL INVESTIGATION
FOflOiW
Three environmental meda (sorts, groundwater, and surface
waJer/sadment) have been adversely impacted by
comamtnation originating from the NSCC plant and from
past chemical handfcig and dsposal practices of the facility.
The primary contaminant at the SUB is 1,2-tfcHoroethine
(U-OCA). This contaminant is known as a chlorinated
organic compound that voiaslzes readily and is classified as
a probable human carcinogen. A carcinogen is any
substance that can cause or contribute to the development
of cancer. Other organic chemicals were also detected.
The chemicals of concern at tie Site are (isted
alphabetically): acetone, bis (2-chtoroetryl) ether, bis (2-
ethythexyf) phthalate, 2-butanone, cadmium, carbon
disuffide, chloroform, chtoroethane, detta-BHC. 1,2-
dchtoroelhene. dkvbutyl phthalate, dHvocty) phthalate,
ethyl benzene, methylene chloride, styrene,
tetrachloroethene, toluene, 1.1,2-trichloroetharw.
trichtoroetiene, vinyt chloride and total xytene. Thefolowing
inorganics were also detected: aluminum, antimony, arsenic,
barium, beryllium, chromium, cobalt copper, cyanide, toad.
manganese, mercury, nickel, selenium, thalium, vanadun,
and zinc.
The OU-3 soil investigation has generated ample information
to characterize the contamination, determine the source, and
define the extant of contamination in the vadoee sol zone.
The vadose zone is comprised of subsurface soi that is not
saturated wan water. The interface between tie vadose
zone and the satiated zone is commonly referred to as tie
water table. Fourteen diflerentvolalle organic compounds,
one semi-voiaie organic compound, and one pesticide were
detected in the vadose sols. The primary source of
contamination in Area 2 were buried, leaking terra-cotta
piping used to tansport waste streams from fie production
area to tie treatment lagoons. The source of tie
contaminants detected in tie lagoon area is tie soi under
and around the lagoons which were contaminated prior to
the lagoons being fned with concrete.
OU-3 defined Ihe nature of groundwatar contamination (tie
contaminarts present and tier concentations} but adolonal
work is needed to completely deine tie extent of
groundwater contamination, especialy in tie bedrock zone
of the aquifer. The aquifer is subdmded into two
interconnected zones, tie shallow zone and tie bedrock
zone. Boti of tese zones have been adversely impacted
by actrvftes at the NSCC plant Sixteen dMerent votatfle
organic compounds and four semi-volatile organic
compounds were detected int» groundwater. Groundwatar
in the shalow zone in the vicinity of the lagoons is flowing at
an approximate speed of 80 feet per year. This rate stows
to approximately 27 feet per year just east of tie lagoon
area,
The highest concentrations of contamination detected in tie
Northeast Tributary were found just east of tie plant The
levels of these voiaSe orgarics decrease downstream as
these contaminants volatize into t» atmosphere. Two
samples, one surface water and one sedmant, were
collected from tie Northeast Tributary just prior to t»
stream leaving the NSCC property and flowing under Airport
Road. No contaminants were detected in tiese samples
wneh mdcates tat the ikefhood of contamination leaving
the Site via surface water/sedment is minimal. The
apparent source of the organic* in Ms steam is tie
discharge of contaminated groundwater into the steam.
inorganics were detected in al three of tie environmental
meda sampled (sols, groundwater. and surface water and
sedbnent). Al of tie metals detected are naturally occurring
and tie variation in concenfatons detected does not
indcate the Site is releasing inorganic contaminants into lie
environment
O»etr-octf
Tributary
"TCg^^^p^
-r^V^V^X.^NO^l >A X**
-------
SUilIlARY Of srTE RISKS
A task of Ihe RemediallnvestigatiolVFeasibility Study is m
analyze and estimate the tunan heaIIh and envirorvnentaJ
problems f\at coUd reSUt I the soil, IP'cxmwater, and
surface water/sedin8tt c:cntamination is not cleaned 14).
This analysis is call a Bas8IIrw RIsk AssassmInl ~
calculating risks m a poJ)Uition if no remedial action is
taken, EPA evaluates Ihe reasonable maxinllll expoS&18
levels for current and fut1n expoS&18 scenarios to Site
contaminants. Scenarios were developed for residents UYing
on or near to the Site as we. as for employees wor1Ung on
the Site. ~ conducting this assessment. EPA focuses on
the adverse human heall1 effects that co~ resUt from
long-tenn daily, direct expoSU'l as a red of ingestion,
inhalation. or dermal contact m carcinogenic chemicals
(cancer causing) as we. as I1e adverse heall1 effects that
could result from long-term expoSU'e to non-carcinogri:
chemicals present at Ihe Site. EPA considers a long-term
resident begiMing as a young child bei1g exposed daily for
30 years Ie be a reasonable maximum exposure scenario for
fullJre exposure Ie the NSCC sita.
A goal of the ~ is to reduce the riSk posed by a
Supertund Site Ie fewer than one person out of 10,000 bei1g
at risk of developing cancer. This is Ihe mnmllll risKlhe
Agerq will dOw, typically Ihe ~ aspires ~ ~ even
more protective and strives m lower Ihe riSk so that at a
minimum, only one person out of one miJion may be
adversely impacted by Ihe contaminttion fo\I1d at a
Superfund Si..
EPA has concluded flat t1ere are no major ~ risks m
human heall1 at the Sits. Exposure pathways evaluatBd in
the Risk Assessment were ingestion, iMalation, and diect
contact Ie contaminants in the soil, grOWldwatsr, and uface
watar/sediment The only reason IJW1dwater does not
pose a CUlTent risk is because the contaminaIion in Ihe
groundwater has not migrated beyond Ihe property bolniary
and consequ&nUy, has not impact any privaaI, polable wel.
There are no polable wels located on Sill.
However, there are ttne InCC8ptat11e M!!! carcinogenic
risks associated wil1.. c:cntamination at the Site. The tnt
scenario reding in an ncceplable !Y!Y!! risk is havi1g
residents living in hOmes tdt on or near the Site and using
the groundwatBr as potable waB. Another ncceptabIe
future risk is the 8J11OUI of a c:RId m SIIfaI:e waIBr,
sediment. and spring waB. The third ~ptabIe M!!!
risk irNoIv8s eJllOsing inIiviclIaJs to contaminatBd
subuface soil. The M!! residenIiaI use of ..
grW1dwater wo~ also red in an ~ fuU8 risk
due m Ihe presence of noncarc:inogri: chemic:aIs in ..
p,ndwater.
A semi-quantitative assessment of .. Northeast Trilutary
was also conducted as part of hi RisUssessmerL This
environmental assessment included chemical. ecoiogicaI,
and toxicological MStigations of the SIIfaI:e waB and
sediment coIeaed from Ihe Nor1heast Tributary. The data
generated by Ihe enYil'Om18nta/ assessment bm adverse
ecoJogic:aI inpacts in areas of hi snam --e eleval8d
levels of 1,2-OCA were detected. However,Ihe assessment
could not conclude that .. contaminants OI9niting from
the Sits, primarily 1,2.DCA, are the sole cause of hs
impact. TheI8 is a ~ inIication that .. naually-4~iting
factors of the stream itself resuts in Ihe cnnshed runbers
of benthic (bottom-dwelling) organisms in lis section of Ihe
Nor1heast TriMary.
REMEDIAL AC110N OBJECT1VES
RemeciaJ action objedives (RADs) were developed based
on the results of Ihe Risk Assessmert. an examination of
potenlial Applicable or A_vant and Approprtatl
Aequlr8menlS (ARAAs), and mats to prdwater and
the Nor1heast Tribulary. ~,Iocam, and
chemical-specific ARMs were examined. Chemical-spec:ific
ARARs for ~ include muJnun concenntlon
I.vlls (MCLs) as specified in I1e Sate Drinking Water Act
and Norl1 Carolina GlOII1dwatBr Stan!WdS. ~ sunmary,
the Remedial Action Objedives are:
FoR GROUNDWATER
For HIIIIan HealI1: Prevent ingestion of water
haYing concentraIions of 1,2-OCA resUti1g in
cancer risks above acceplable limits.
For EnvitomIentaI Prot8dion: None. grooodwater
concentrations have not been fo&m to represent
an envionmentII hazard.
FoR SURFACE WATER
For Hllnan HealI1: None. surface water is not a
dmking wailr SCUC8.
For EnviromIemaI ProtBdion: NcwIlS, uface
waiIr concentrations have not been identified as
.. sole cause tar !he limited ~ popUitions.
FoR SEDIMENT
For HIIIIan HeaItI: Prevent direct contact .11
seciments having levels of 1.2-ocA reSUting in
cancer risks above accepable linits.
For EnvionmentaI ProtBdion: None.
--r 1""
The obiedM of a remedaJion is m obtain sringeftheaJl\
. risk levels. For pnt«ater, aI chemical-speciic ARARs.
which include MCLs and .. NorIt Carolina GIw1dwat8r
Standards. wi be actI8wd where the specifiBd
c:oncennIion is 8dIicaIy dnIdat8. 'The esaInatBd
voIlIII8 of conIaminated pnMa8r reqUring remeclation
is 131 mlbl gallons.
"
-------
For more ntonnaDon about !he Remedial Adion OCjediYes
and altematives for.. NSCC 00-3 Site, please retBr 80 ..
June 21, 1993, Feasbity SIudy doaInert and other
doaInents awilable for review at the Alinirisntiw Recotd
Jocaed at the Rowan N* Ubraty.
SUIIMARY Of REIIEDW. AL 1ERNAT1VES
The following section provides a sunmary 01 !he alt8matives
developed ;, the FeasibiJty Study (FS) Report. The prinary
objective 01 !he Feasibility Study was 80 detemliwJ and
evalualB alternatives for cl8aRng up !he $ita. Descriptions
01 !he clean-up alternatives are ammarizad below. The
Repo/1 contains a more detailed evalualiorVdescription of
each alternative.
The cost information provided below for each alternative
represents estima8Eld total presert WOItI (PW) of eactt
alternative. Total prem wort! was caIQAtBd by
combining the capital cost plus the JnS8nt WOlIt of the
annual operating and maintenance (OIM) costs. Capital
cost includeS consrucIon, 8I1gi.mg and deS9\
equipment, and sita developmert. Operating costs were
calaJlalBd for activities that conti,.. after completion of
c:onsttUction, such as routine operation and mai1t8nanc:8 of
treaIment eqUpment, and ~B moRtDring. The
present worth of an altemalive is .. amOUll of captaI
requied to be deposi8Eld at the present time at ~ ~
interest rate to yield the total amCUlt necessary 80 pay for
initial construc:tion costs and fuUe expendives, incIudng
operation and main8BnanC8 and "JUt replacement of capital
eqUpmert
REMEDIAL ALTERNATIVES TO ADDRESS
GROUNDWATER CONTAMINATION
The ~tBr remeciaI aI8natives far adchssilg
contaminatBd ~ were ConsideI8d separUIIy for
Atea 2 and t1e lagoon area. Atea 2 aIIBmidves are
identified by op- for b PIn and fie aII8matives deaIi1g
wit! t1e contamina8EId ~ as~ with tie
lagoon area ant idrited by "L".
ALTERNA11VES GWP1 AND GWL1: NoAcrloll
CaPtaI CosIs:
AtnQI O&M CosII:
Total PW Costs for 30 V...:
Tame to Desi!J'l:
Consrudion Tme:
D\ntion 80 Adieve ~:
S 0
S 22.000
S 227 fXXJ
None
None
CMr30years
CERCLA ~ hit .. "No "*'" aII8maSM be
evaluatBd at Mtrf ~ SilBID esIabIsh a baseh far
comparison. No fw1tw adlvitiBs woUd be concU:I8d will
regard 80 tie ~ beneaIh .. 58 "* iii
alBniM Q.B., tie sa is 18ft "u 1s1. Because fI8Se
alternatives do not enIai conIamnn remoVal or desructIon.
a reYiew of.. remedy wWd be concb:8d '*Y tve )UI
in accordance ~t! CEAW Section 121(c). ~tng
costs are based on c:orWdi1g tis review every five years
which includes monitoring tie IJOU*;tsr I.I1det t1e $ita
once evwy five years tar a s*od of 30 years.
ALTERNAT1VES GWP2 AND GWL2: LOIIG 7tIII
IIONITOIWG, F'EJIcIIG A PoIITrJIt OF NoImIEA.ST nwUTARY
Capital Costs:
ArIWI O&M Costs:
Total PW Costs for 30 Years:
Time to Design:
Consruction Tame:
O\Iation 80 Acheve ~:
S 178fXXJ
S 138.000
$1,419,000
None
None
Over 30 years
These alternatives all siniar 80 Alternatives GWP1 and
GWL " e~ "* Altlmatives GWP2IGW1.2 additional
mriDring wells woUd be instaIed. pmwaB mcmmg
data woUd be coIedBd amaIy hst8ad of once Mrf five
years, and a portion of fie Northeast Tributary ~ be
fenc8d.
ALTERNA'T1VES GYm AND GWU: INsnnmcHAL
COImfou, FfNcIC A PoImoII OF NoIInEAsT T18IrARY
Capital Costs:
AINII O&M Costs:
Total PW Costs far 30 Years:
Tame 80 0es91:
Consrudion Tune:
0I.rati0n 80 Ad1ieve CIearH.Ip:
S 198,000
S 138.000
$1,500,000
None
None
Over 30 years
These altBmatiYes for ~ conIamination ;, Atea 2
and tie lagoon area all identical to MImatives GWP2 and
GWI.2, except AItBtatiYe GWP3IGWL3 n:tudes institutional
controls. No remecIation adMIes wWd be concU:t8d for
~. The adcItionaI costs are ,~~ wit!
preparing and ling deed I8Aicb1(s) and inplemenling t1e
other i\stitutionaI cornIs. The spec:iIc institutional conRIs
to be implemen8ed indud8: usi'Q deed resrtctions 80 conroI
fie insIaIIdon of new wells on both tie plait property and
~ property; track pIIInI mValion; and NtaII fenci'Q
arOW1d tie NortIeasI Tributaly 8D limit acc:esa 80
c:ontaminamd SIIface waISt and secimert. A "JUne" is tie
dsc:hargl of a ccnlaminart tom a c;wn pan of origin in
wa8r or 8, for example, smoke from a smok8l8aCk.
These alternatves proWie no recu:Iion in voUne, motliity
or 80xicity of tie conIaminanIS. how8Y8r, they can recU:8 or
ellniraIB cbct expoue palhways and .. r8darC rI8 80
fie p&dc. AI pIWt of ... _.111--. .. ~
woUd be rncriDred on a ~ bIsiL AI EPA may not
have !hi Uhori\y 80 inp8meri ... ntUIoRiII canInIIs,
. the ~ I'IStI wIh b S8III of North CIroIna 80
enue .. i'IstituIIonaI conRII are in -, .. 1811ab1e,
and wiI remai'I ;, - aftBr ntiation of O&M. 'TMnIfort,
fie respondJity tar inplemenllng and enfardng insIUionaI
COI'C'OIs tails on .. Sial of Norf\ C8oh. GnxnMamr
~ and tve )1111' CEAClA rMIwI wac.if be
6
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conducted tor 30 years. The 0&t.4 cost is tor bot1 Nea 2
and the lagoon area.
ALTERNATIVE GWP4A: GROCIICIWA7lR Emucnoll
THROUGH WELLs MID ntEA71DT BY AiR STDPMi WITH
V AJ'OR..PHAsE CA/fIOII AlJsoIVrnoII
Capital Costs:
AMJaJ 0&t.4 Costs:
Total PW Costs tor 30 Years:
Time to Design:
ConslnJdion Time:
Duration to Actieve Clean-up:
S 648.000
S 306.000
$2.222.000
1 year
6 montls
15 to 30 years
This altemative iQJdes exncting grw1dwater by means
of exnction wells cIowngradient 01 Area 2; volatile organics
removal t1rough ai stripping; c:ontroI 01 emissions m tie
atmosphere tram .. Ii strwer ItrcMq1 vapor"
carton adsolption; and comtined Qschalge will teatBd
grounct.„ater from QU.1 ID the SaJistuy ~ owned
treatment wor1
-------
emissions i) ht unosphefe from h at stripper ItY'ougn
vaporiNSS cart)on adsorption; comtIirW1g a pottion 01 ..
discharged pI1dwaI8rwitl tr8Dd pI1dwaterfrom 00-1
for di~ i) '- SaIstuy POTW. poIisOOg h
remaining portion of .. pI1dwailr by ai strippr,g i)
cIeaBJp goals before i;edIng ht Ir8at8d ~18r along
with rwients inID .. cancami1at8d area i) promo. IrHlIU
biodegadation of h c:cnIaminanIs. "Mjtu" means to keep
in place (1.8., the treatment is c:ondud8d in its original place).
The treated effluent being cischarged to .. Saistuy
POTW must meet pennit Imits set by h Salistuy POTW.
Spent activated carbon would be regeneralBd. The five year
review CERCLA requirement would apply i) Ins allemalive.
ALTERNAT1VE GWLSB: GIIOtWDWA7EJI ExTRM:nDN
WELLS, TREATIIENT BY AIf sru,1IG MTH ,..
INCINERATJON, /N-SmJ BIOREItlEDlATION REOUIRING
GROUII1WA7fR INJECTION OF MmrBtrI
Capital Costs:
Annual O&M Costs:
Total PW Costs for 30 Years:
Time to Design:
ConsiucIion Tune:
Duration i) Adieve Clean-up:
$1.365,000
S 733,000
$7,000,000
1 year
6 monlhs
15 to 30 years
This aI\Bmative is sinilar to AItBmative GWL.5A except
control of emissions of the vapor coming from .. Irst air
stripper would be accomplished h'ouI;;I the use of a f\.me
incineration.
AL TERNAT1VE GWL5C: GIIOlMDWA7EJI EmIAcTJoII
THROUGH WELLs. TREA7IIE1tT " LIoCJD.PHAsE CARBON
ADSORPTION, INeSlTu BIOREJlEDIATIOII REOUIIIIIIG
GROUIC1WA7fR INJECTIOII OF MmrENrI
Capital Costs:
ArnJaI O&M Costs:
Total PW Costs for 30 Years:
Tune to Design: .
Consrudion Tillie:
D\nIion i) Adieve ~:
$ 1.216,000
S 1.631.000
$13,853,000
1 year
6 months
15 to 30 years
This ahematiw ndudBI exrdng ~ by means
of extraction WIIIIDc8d downpIert of .. lagoons;
volatile organa rIIICMIf ~ ~ ClItIon
adsorption; combir*'8l por1iDn of.. cIsda'ge with natBd
gr~ tom 0tJ.1 far cIschargi'Ig i) .. SaIistuy
POTW; the remamg potIOn Of .. reaIBd pntwIter '
would be ,.q&dBd. along wiI1 IUrients, back I1ID ..
c:onIaminatBd area to promo. n-sq, biodepiation of ..
contaminanIs. The Ir8a»d efIk8t being cIscharged to ..
SaIistuy POTW will meet permit linits set by '- POTW.
Spert actiYaI8d calton would be changed u and 811 to a
commercial I8g&1I8rcItion facity. The M year nMew
CERCLA requi8menI would apply. The naI8d etIuIn
must meet permit limb set by .. POIW. The five .,.
. mi8w CERClA recpemeri woUd - to lis ahBmaIWI.
REllEDW. Al.1ERHA11VES TO ADDRESS
SURFACE WATER AND SEDIMENT
CONTAlllNA11ON
AL TERNAT1VE SW1JSD1: No AI:noII
Capital Costs:
AmJaI O&M CoSlS:
Total PW Costs for 30 Years:
Time to De.:
Consruction Time:
Duration II) Achieve C~:
S 0
S 16.000
$151,000
None
None .
Over 30 years
No Uhr activities woUcI be c:oncU:I8d on ufac:e water or
the sediment in the Nc~~3St Tributary. As with Alternative
GWP1/GWL1, this snam woUd be left "as is". Samples
would be coIect8d and analyzed eY81Y five years as pan of
t1e five )liar "view CERCLA I8CJiIIment whictI .y i)
this aIt8n1IIiWI.
At TERNAT1VE SW2$D2: LDIG-TEIw IIoIlTORllG
CaptaI Costs:
AmaI O&M CoSlS:
Total PW Costs for 30 Years:
Time ID De.:
ConsrucIion Tune:
Dwation " Adieve ~:
S 0
S 92.000
$867,000
None
None
Over 30 )'9aI'S
'nIs allBmative is sinilar " AII8mdve SW1 ISD 1 , except
II1der Mlmalive SW2JSD2, uface water and sedinent
samples woUd be c:oIec:t8d tom .. Nor1heast TrbIIary
arnsDy i1SI8ad of once every lYe )WI.
CHIleniA FOR EVALUATItG RfJlfOW,
AI. TERNA11YES
EPA'S selecton of the pr8terred cIearq) aItBmdY8 for..
NSCC 00-3 site, as described " tis Proposed Plan. is..
red of a comprIIhensM evaluation and scr8ri1g pnIC8SS.
The Feasibility Study lor .. SiB wu COf1IU:8d " ideI'*fy
and analyze .. "'11d- COIIIider8d far Idci8ssiIg
contaminaton at .. SIt8. 'The FtasibiIty SIUdy and ohIr
doc:unents lor '" NSCC ()U.3 ... describe, " detaI, ..
aItBn1atIH consider8d. as W8I as .. process and critBfia
EPA used " narrow ..lilt " pollnlal remeciaI aIIIrnaIves
to adci8ss tie Sill contaminaIon. M stamc:I previously, II
of "se docunenlS 118 avaIabIe lor ~ mi8w in ..
intormation repository/Unirisnive f8COfd.
Ah8maIiveI GWNC, GWL4C, GWL5A, GWLSB, and
GWL.5C WIll not I8tai18d far .. detailed analysis b8caus8
. '- otwr ~,WUd IdIM .. ... -- of
pro88dion for tunan .., and .. ...... tU at a
aiJstanIaIIy lower cost. . ~.".: ;-:..~ .~ .
. . . ,-
EPA always UI8I" tIIMIng _'~ID MIua8
~ ideldled " .. FtasIIiIty SUty. .". rwneciaI
*"'dvel8lec:8Bd tar I ~ 8it8 must actiM ..
8
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two heshOld crin as well as attain tie best balance
among !he five evaluation criIetia. The line criteria ate as
foUows:
THRESHOLD CFlTERIA
1.
Overall orot8C1lon of hllnln hIItth and the
environment The degree to which each
alternative elirnirlaEs, reduces, or conroIs
thr8ats 10 IU* heatIh and tie environment
hough b'eatment. engineering melhods or
institutional controls.
2.
Comollance WIth ADDIlcabie or Relevant and
ADDrOOffate Reaufrements (ARARs): The
alternatives are evaJualBcllor compliance with all
state and federal envirotVnettal and public health
laws and requirements !hat apply or ate relevant
and appropria89 ID tie si89 concitions.
EVALUAT1NG CAlTERIA
3. Cost The benefits of inplementing a pat1icuIar
reiTi8daI alternative at8 weighed against tie cost
of implemen1ation. Costs incUie tie capital
(up4ronQ cost of implementing an altemahe 0*
the long 181m, and !he net present WOIt1 of both
capital and operation and mai1t8nance costs.
IrnolementabnltY: EPA considers tie tBd'nicaI
feasibility (e.g., how difficult tie aItsmative is ID
construct and operate) and admnstralive ease
(e.g., !he amNW of coordination with other
government agencies that is needed) of a remedy,
inc:lucing tie availability of necessary materials and
services.
<4.
5.
Short.term lffectIveness: The length of Wne
needed ID implement each ahBmatw is
consider8d, and EPA assesses tie risks that may .
be posed ID worUrs and nearby residents fUi1g
construction and implementation.
6.
Lena.term 8ftK1Iv8n8SS: The all8maMs ate
evalualBcl based on hir abiity to maintain reliable
protection of P'iIIc heaIIh and .. environmeri
over time once .. cIearI4I goals haw been met
Reduction of cantlmlnant tDlIcItY. mobftltY.
and volume: EPA evaIuDs each aII8mdY8
based on how it r8CU::8s (1)" hann~ naue Of
tie conIami1ants. (2) tI8ir abiIIy II) move ~
!he 8I'IYiorInett. and (3) .. VOUne or IIIIOW1I Of
contamination at tie sill.
7.
MODIFYING CRITEJU
8. Statt ICC8DtInct: EP A r&quests state comments
on tit Remedial ntstigalon and Feasibility
S1udy reporIS, as MIl as .. Proposed Plan.
and must take inID consicIeration whether ..
9.
StiIB conc:us wi". OR)Oses, or has no comm8lt
on EPA's pt8fer1'ed aIt8matiYe.
Comnu,,'tv ICC8OtInct: To enan I1at ht
public has an adequa89 ~ II) provide
input. EPA hOlds a p.dc comlll8lt period and
considers and responds to all comments received
from ht comm~ prior II) !he hi seIedIon of a
remeQal action.
EV ALUA110N OF AI. TERNATIYES
~
The following sunmary profiles the performance of tie
preferred altamalws i1 89rms of tie nine ev.Wition Cti89na
noting how it compares II) the other al89matives IJ\der
consideration. The comparative analysis for tie
groundWater remediation a/tamatiY8s is as foIows:
GROUNDWATER REMEDlA110N
The toIlowing a/l9matiY8S were ..led 10 detailed
analysis for m9ition c:onroI:
Alt8matlve GWP1: No action . regard to tie
gr~tsr in Area 2
AItImItIv. GWP2: Long-Term GroImwater MoRlDring of
in Area 2 will Fencing A Portion of NorIIeast TrtIutary
AItImItIv. GWP3: InshJtionaI ContoIs with I8gaId II) the
grMdwater in Area 2 with FenciIg A Portion of
Not1heast TrbJtary
AJt8mltlVI GWP4A: GrMcMater ExracIion TJrotqI
Wells DowIIpient of Area 2 and Treunent By M
S~ . Vapor-Phase CartIon Adsorption with
Combined DischaIge II) ht Saistuy P01W
AIt8matIv. GWP4B: GroIr1dwaB ExracIion ~
Wells DoWI91IieIt of Area 2 and Treanert By Nt
StI;IPng WIth F\Ine R:ineration will Combined
Discharge II) the Saistuy P01W
AJt8mltlVI GWl.1: No Action will regard 10 ht
pnMater in tie lagoon area
AIIImItvI GWL2: Long-Term GrMdwa89r MoIiIDring of
... the lagoon area with Fencing A Porton of Nor1heast
TrbDty
& 1IITIIIVI GwU: InsftJIionaI C4doIs wilt! regard II) ht
p.ndwater in the lagoon area will Fencing A Portion
Of NoI1h8ast TrIUary
~ GWL4A: ~ EnacIon ~
Well DownpIert Of .. Lagoon ArIa and
Treatmert By Ii StriA*1g wilt! Vapor-PhasB CartIon
Adsotption witI Combined Disd8'ge II) the Salstuy
P01W
9
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Alteml1lv. GWlAS: ~ Extraction ~ Wells
Cowngradent of h Lagoon Area ana TlNUnent By
~r Slri~ng Wit! Fune ~tion with Combined
Discharge to the Salstuy POTW
Overa/I Protection: NI8maIvu GWP2. GWL2. GWP3,
GWL3, GWP4A, GWl4A, GWP4B, and GWl4S provide
adequate protection for tunan heaJtI by prewnting
ingestion of potantialy contami1al8d ~ ana
suface water. Altematives GWP4A, GWP4B, GWL4A, ana
GWL4B would afford tie ~test protldion to tunan healt1
because ~ would substantially reduce tie contamination in
the groundwater and prevent tie potential tor expoSUfl
through use of existing or futLn ('If sill wets. AI18maIives
GWP4A, GWP4B, GWL4A, and GWL4B woUd also
remediate tie utace water ana seciment, wtic:h woUd
eliminate the potential for expoS&1'8 via i1gestion of llese
media. These aIt8maMs protBct the enWorInenl by
removing contanINnts from ~, conroIing tie
extent 0' ~ter contaminaIion. ana reciM:ing tie
contamination in tie ~ and downsream S&Iiace
walers. Neither Alternatives GWP3 nor GWL3 woad protect
the enYirorvnent because contamntion woUd contitut to
migrate inti:) the tribuIary tvoIqt ~ -=narge.
None 0' tie Altematives GWP1, GWL1, GWP2. or GWL.2
wi. provide proBdion tor either tunan heaIIh or ..
environment Natural degradatiorVattenuation of
contaminants in tie UUface is not anIicipa!8d ID prevent
the potential m9ation of contaminants off sill, aIt1ouI;I
such processes may r8CU:8 .. arncMI1t ana concentraIion
of contaminants.
ComDiiance with ARARs: AII8mativ8s GWP4A, GWP4B,
GWL4A, and GWL4B woUd obIain perfonnance standards
for grw-dwatBr (MCls and North CaroIi\a GroIniwater
Standards), S&Iface waIBr and I8CImert at lie poit of
comp8ance. These ahBmatives woUd also comply wit!
location- and action-specik ARARs related to lie clschaIge
ID tie POTW and ai emission COIW'O& AhIImaIws GWP1,
GWL 1, GWP2, GWL2. GWP3, and GWL3 III not.JI)8C88d
ID meet petformance SIardards at the poit of compiance,
however, AI18matives GWP3 and GWL3 wWd comply witI
the location-specific ARAA r8IaIBd to operatons at a
hazardous was8It sill.
- LonQ.tenn Effec:tMn8Ia and Permanence: AI18matives
GWP4A, GWP4B, GMAA. ... GWL.4B wWd provide an
eff8ctive and pennnnI-**" for ~, S&Iiace
water, and seclment becaus8 b d8niCall of concern
woUd be removed tom .. ~ and deA'oyed.
The I8Iiabiity of ... IIIiBmaII'teI is ~ Tt88
aIWndwI MUd not poll . tunan I1I1II1 or
enYinnnenIaI risk at b poirt of complancl Ind no
treatment residuals woUd be left on Sill. AIt8md""
GWP3 and GWL3 wWd prevert poten18 '*" ri* br
prevenling b ins8aIIaIon of ctriing well in Ilrt ...
exceedng MCLs or North Carolina ~ SIandardL
MImatives GWP1, GWl1, GWP2, and GWL2 wiI not be
protBdivl of tunan twaIIh and .. envirormert in blong
tenn because Ih8se aIt8rTIatMs do not fIInCM, Rat, '"
iSOlate USU1ac8 conIamnmon. Five ye;JI CEACl.A
manaa.d I8views wi be ~ for II of .. a/IBmatives.
Reduction of ToxicitY. MobiIty or VoUn': All8matives
GWP4A, GWP4B, GWL4A, and GWl4B woUd r8CU:8 ..
1Dxici1y and voUnI of c:rnamNIion in ~ ~
removal and Ir8aIrnIrt They waUd 8so I'ICU:8 btoxicity
ana voIune of conIamination in utace waI8r and secJmert
Mtmatives GWP1, GWL1, GWP2, GWL2. GWP3, and
GWL3 do not cfncIy r8CU:8 toxicity, motIiIty, or voUne of
",Mdwater, uface wa. or sedirnert c:rnamNIion.
Short-term Effectiveness: All of the altematives can be
implemented ~ S9itcant ,. to h convnllity or
on-siIB WOtt!8rs and without adverse enWomIen1aI impacts.
ImDlementabllity: None of the alEmiitives pose sigificant
conc:ams regarding implementation.
Cost: To" present wort1 costs (based on 30 )'8CUS) for..
grMCttvater alternatives are pre~ below:
AIt8mdY8I GWP1IGWL1 . No action: $227,000
AItImItIv. G'Nn'GWL2 . Long- Term Monitoring will
Fencing A POI1ion of NoI'ItIeast TritUary:
51,479.000
AltlmltlVII GWP3IGWL3 - InstiUionaI ConroIs with
Fencing A POI1ion of Northeast TritUaIy:
51,500.000
AII8mItM GWP4A . GrW1dwat8r ExIracIiorVAi
S~.fIhase Carbon AdsorptiacVPOTW
Disdwge: " ~~ OM
Aft8mdvt GWNS . GrouIMat8r ExIracIiorVAi
S~r9fUne InciIeratiorv1'OTW Discharge :
12,274.000
Alt8mltlve GWUA . Gro&niwaI8r ExIracIiorVAi
S~'9'Vapor-Phase Carbon AdsorptiacVPOTW
Discharge: $3,510.000
Altlmdve GWUS . Gro&nMaI8r ExIracIiorVAi
StJippif9'Fum. IncinerationlPO'tW Discharge:
$2.996,000
SURFACE WAT'EIWEDIIEN1'
The foIIcMing aItBmaII„8I ... ,,~ » d8taiIed
analysis for 8IIfaI:8 .. and IIdIrnert IIIIIICIaIon:
. AII8mItM SW1JSD1:
AIt8mdV8 SW2ISD2:
No Action
Lq- Term MoriIDItng
0veraI Pro88Ction: U1dIr pr8S8rt con._, boll
AIEmaIMII SW1/SD1 and SW2JS02 MUd be PfO*thte of
tunan h8aII\ tu may not be protec;tw of.. enWormert.
10
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If hip conc:ennDons of ccntaminants are cisd1arged 1m
the snam .-om .. ~, lien neihr aIt8rnatMt
may be pro8BdiY8 of lunan heaIt1 nor the enWomIeIt.
ComDiiance witt ARMs: There are no FedetaI 01 StaB
AAARs for the contaITInnts del8dBd in tie ufac8 waI8r
or sedimeri.
lono-tenn Effectiveness and Pennnnce: Under M1Int
conditions. A/1Bmatives SW1/SD1 and SW2ISD2. wU:t be
prolective of tunan heaIIh but possibly not the enWomI8It.
If higher concenlrations of contaminants begin discharging
inID the bibutary, none of these all8matives may be
prolective of tunan heal#!.
Reduction of Toxicity, Mobifitv or Volume: Both AIt8matiYes
SW1/SD1 and SW2ISD2 coUd lead to a reduction of voIaJiIe
contaminanIB i'I tie 1ribuIary, howewr. neiIW of ...
all8matives woUd red in .. ~ of the volatile
comaminanl$. These contaminanls woUd be Iransfen'ed
from tie Dibutary to the unosphere ~ tie process of
volatilization.
Shan.term Effectiveness: HI of the alternaIYes can be
implemented without significart risk " the commlllity 01
on-sits ~rs and without adverse enWomtental impacts.
ImDlementabilitv: None of tie ~ pose SIg1ficant
concems regarding mplem8nlatiDn.
Cost: Total presn wortt co. (based on 30 years) for tie
SIIfac:e watBr/secinn aIt8maIv8s 118 preser8d belOw:
AJt8mdVl SW11SD1 . No Adion:
$151,000
AJt8mdVl SW2ISD2 . I.Dr9- Term MorRmg: $8671XXJ
StaIB Acceotance: The NCDEHNR has reWIwed and
provided EPA wi#! comments on tie repot1S and data from
the RI and tie FS. The NCDEHNR has also reviewed IRs
proposed plan and EP A's prefened a/lemative and presenGy
concws with EPA's selection.
Community AcceDtance: Comlnllity acceptance of tie
premed allemUW wiI be evaIuaIed after .. pU)Iic
comment period ends and a,..,. III each comment wi
be included In a RlSpOllslvtnlSS SUnInIry wI1c:h wit be
a part of tie Record of DecIsIon (ROD) for the Sill.
11
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EPA'S PREFERRED ALTERNATIVE
After conducting a detailed analysis of all the feasible cleanup alternatives based on the criteria described
in the previous sections, EPA is proposing a cleanup plan to address groundwater, surface water, and
sediment contamination at the Site. The EPA preferred alternatives are:
GROUNDWATER REliEDIAT10N
ALTERNATIves GWP3B AND GWL3B: Long-Term Monitorif9lnstitutional Controls; ALTERNATIVE
GWP4B: Groundwater Extraction Through Wells and Treatment By Air Stripping with Fume
Incineration; and ALTERNATIVE GWl4B: Groundwater Extraction Through Wells and Treatment By
Air Stripping with Fume Incineration and Combine Treated Groundwater with Groundwater from 0tJ.
1 for Discharge to the Salisbury POTW
At a cost of $1,500,000, $2,279,000, and $2,996,000.
SURFACE WATERISEDIIIENT
ALTERNATIVE SW2ISD2: Long-Term Monitoring
Cost: $867,000
An active groundwater remediation alternative would reduce the levels of contamination in both the
surface water and sediment as the source of this contamination is the discharge of contaminated
groundwater along the section of the Northeast Tributary.
OVERALL TOTAL PRESENT WORTH COST OF $7,637,000
Based on current information, these altematives appear to provide the best balance of trade-offs with
respect to ~ nine criteria that EPA uses to evaluate altematives. EPA believes the preferred
alternative wiI satisfy the statutory requirement of Section 121(b) of CERCLA. 42 USC 9621(b),
which provides that ~ selected alternative be protective of human health and the environment,
compy with ARARs, be cost effective, and utilize permanent solutions and treatments to the
maximum extent practicable. The selection of the above alternatives is preliminary and could
change in response to public comments.
12
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COIIIIUtITY PARTJaPAT10N
EPA has developed a commLlity relations progam as mandal8d by Cor9'ess II'der ~ II) respond to citizen's concerns
and needs lor information, and II) enaI:II8 residents and public officials to ~ in .. decision-making process. P\dc
involvement activities &n:iertak8n at Supemn1 sites consist 0' in8rviews with local resicients and eIec:8d oflcials. a commllity
relations plan for each site, fact sheets, avaiabiity sessions, pubic meetings. p&.tIIic commn periods. ~ adver1isements,
site visits, and Techrical Assistance Grants. and atr'I other actions needed to k8ep the comnuity informed and inwIved. .
EP A is conducting a »day public COII'IDI1t period from ~ 19, 199310 August 17, 1993, to proWie an opportInty lor ~ic
involvement in selecting the final ~ method lor ttis Site. Public input on all aJtematiYes, and on the infonnaIion I1at ~
the alternatives is an impor1ant c:ontrhrtion II) the remedy selection process. During tVs comment period, hi public is i1vited II)
atlend a public meeting on August 3, 1993, at hi AgricUtInI Extension Centsr Auditoriun, 2727 Old Concotd Road, Sa/istuy,
NOt1h Carolina begiMing at 7:00 p.m. at which EPA wil present the RemeciallnvestigatiolV Feasibiity Study and ProPOsed Plan
describing the preferred a/tamative for treatment of .. contaminal8d ~ter at the National StW1 & Chemical Company
Superfund Site and to ansMI' any questions. Because ttis Proposed Plan Fact Sheet provides MY a unmary desctiption 0' the
~ alternatives being considered, the public is encowaged to consul the mormalion repository for a more detailed
e~
During this 3O~y period, the public is invited to "view all site-relal8d docunents housed at the infonnation repository located
at the Rowan County Pubic Library, 201 West Front Sb'eet, SaIisbuy, Nott\ Carolina and otter comments to EPA either oraIy at
the public meeting which wi! be recorded by a cout reporW 01' in wriU8n fonn CUIIg tis tine period. The ai:UI remeda/ action
could be diffnnt from I1e preferred altElrndve, depending ~ neW information 01' statements EP A may I8C8ive as a red 0'
public comments. If you prefer II) submit writtan comments, please maillhem poS81latkad no lallr I1an m~ August 17, 1993
to:
D8nt 8Itr8tt
He CtJmnuJIty RtIatIon8 CoardIn8W
U.s.£P.A.J Rlglon 4
NGrfh RMrJ4IdW &.fwtund BrIncII
34S CouttlInd SIrM, HE
AtIIntI, GA 3D3U
All comments wiI be reviewed and a response pr8piII8d in maJcing the hi detllmli'lalion of the most appopriaIB ahBmative for
~1m8rt of .. Site. EPA's final c:hoic8 of a remedy wi! be issued in a Record of Decision (ROO). A docunert called
a ResponsI~ SunInIty unmarizing EPA's response to aJ public comments wi also be issued with the ROO. Once 118
ROO is silJ"lBd by .. RegionaI14*nnsntar . wiI become part 0' I1e Aannsntive Record (Iocat8d at I1e Ibary) which contai1s
all docunel1tS used by EPA in making a final determination 0' the best ~ for the SitB. Once the ROO has been
approved, EPA wi! ~ negotiations with .. PaI8nIIaIIy RIIponsibII PIrtIII (PRPs) ID allow tan .. oppor1IIiIy ID desigI,
implement and absort) aI costs of the remedy delBnnl1ed in hi ROO in accordance wiIh EPA gUdance and prolDcot "
negotiations do not "sUI in a setIIerneIt EPA may conduct the remedial actvity using SupeItn1 Trust mories, and sue for
reintusemeft of its costs wiIh the assistance of .. Depar1nert of JUSIIc8. Or EPA may issue a &I1Ia8raI Dninisntive 0fd8r
01' cIrectfy lie sUt to force .. PAPs ID c:anduct .. remecia/ activity. Once an apJmert has been reached, .. de. of ..
selec:tBd remedy wi! be developed and inIpIementation 0' 1he remedy can begi\. The precediIg adions are .. standard
procecUes utiiz8d cUing 1he ~ process.
As part of the SuI8tnf propn, EPA pmides affecf8d com~ by a ~ sill . the oppoIU1Iy " apply for a
Tectri:aI AssistInCI GIn (TAG). Ttis pt of 14) to $50,000 enables the P41to tn a I8CtIicaI advisor 01' consutart to assist
them in interpreti1g or commenting on sill fIdngs and proposed remecial action plans.
For lIIOI8 informdon concerrq tU p1t Pf'OIJIIII, please conIact:
.... HOIIIDItJ PIffDn, CGorcbfcr
He TIdDt;8 AaIStInc:t GIIIIfI
Wllf8111n1g1mMt DMIIon
U.S.£PA., RegIon 4
34S COfIfIInd SIrM, HE
AfanfI, GA 8M
(4MJ 30-1234
13
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INFORMATION REPOSITORY LOCATION:
ROWIn Ccu1Iy PublIc LInry
201 Will FIsher SIreet
SIIIsIuy, IIDrth CIroII. 28144
PhanI: (704) 633-5578
HcuI: 1IondIr. FrIdIy .. un. .1. p.m.
SIUdIr 1:00 un. . 5:00 p.IIL
FOR IIORE INFORIIAT1ON .-.sour SITE AcnvmES, PLEASE CONTACT:
1Ir. Jon Bom." R8mIdIII Project "'1IgIf .
lis. DIInI 8In8II, He Camnu1fty ~ CoordInIIar
Nartb SUperUId RemIdIII BrInd8
Willi ........... DIvtsIan
u.s. ~DI p.utectIcMI Ager:f, RIgIan IV
345 Ccu1IInd SIn8I, HE
AIIInIa, GI 30365
101 FrI8 No.: 1~
GLOSSARY OF TEllIS USED II THIS FACT SHEET
Aqu/flf: Ail ~ ~ fonndon, Ot'P4» of formatianI. COIIIaiI.1Q usable amCXI1IS of~thatcan"y
wels and springs. .
Adnnlstrltlvl RIcGtrI: A lie wtIch is mailland and conan. II nonnaIon used by .. lead agency » make iIs decision on
the seIedion of . mef1Dd » be uIIz8d » cIIan ~ COI'8fti IIIon . I ~ 1iII. 'RIlle is held i1 .. nonnaIion
reposilElry for P'* ntview. .
AppIlcMW tJI ""... - Apptoptfm ~ (ARARI): TN IIdIni and stall ~ bit. seIed8d remedy
must dai1. Th8s8 ~ may vary among - and variauI ........--.
".""., lilt ~f JJSfft81t A men of esIma1i1g the anICU1I of diimIOIl ~ III cUd ~ to tunan heaIIn"
8I1W'of1nn. QIiecMs of a risk assessmn are to: help detlrmiw b need for action; .. deCBnnire blMl8 of chemicals
that can remain on .. Sill a1I8r c:IearI4) and stiI prot8Ct heaIt1 and blfNir'orlnenl; and pmidI a basil for com~ cIIIInrt
dearq) metlOdL
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C'rcJlJOQen; Atrf substance that can cause or contrbJt8 i) tie production of cancer; cancer~.
C~Vt EnvIronmentJI RtSpOIISI, CotnptnsItIon IItd U.bllity Act (CERCLA): A lederallaw passed in 1980 and
modified il1986 by the SupetMd Amendments and Reauthorization N:t (SARA). The Ads cr&a8d a special tax paid by
producers of varioUS ctIemicaIs and oi products hit goes into a Trust FIIId. commonly known as ~ These Ads ~
EP A tie authority 10 irMIstigaIB and clean ~ abandoned or lIICOIWoIed hazardous waste sites utiizilg money m the ~
Trust or by taI
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MAIUNG UST ADDmONS
If you .. net .. on OW mall~ lilt Ind wUd ... to be pllC8d on '" 1181 to rIC8tvt Man ~ on III
NItIonII SIIn:ft I ~ ~ ~ SIll, pi... COft1Ht8IN1 bm Ind IIUn 80 DIn 8IrTIII, Cornntr
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APPENDIX C
RESPONSIVENESS SUMMARY
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RESPONSIVENESS SUMMARY
FOR THE
PROPOSED REMEDIAL ACTION
FOR OPERABLE UNIT #3
NATIONAL STARCH & CHEMICAL COMPANY SUPERFUND SITE
SALISBURY, ROWAN COUNTY, NORTH CAROLINA
Based on Public Comment Period
July 19 through September 16, 1993
Which Includes August 3, 1993 Public Meeting Held In
Agricultural Extension Center, Salisbury, North Carolina
Prepared by:
U.S. Environmental Protection Agency, Region IV
September 1993 '
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RESPONSIVENESS SUMMARY
OPERABLE UNIT #3 PROPOSED PLAN
NATIONAL STARCH & CHEMICAL COMPANY SUPERFUND SITE
TABLE OF CONTENTS
SECTION
PAGE No.
1.0 OVERVIEW[[[ 1
2.0 BACKGROUND[[[ 1
3.0 SUMMARY OF MAJOR ISSUES/CONCERNS/QUESTIONS/STATEMENTS
VOICED DURING PROPOSED PLAN PUBLIC MEETING AND RESPONSES. . . .. 3
3.1 SOIL REMEDIATION ALTERNATIVES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4
3.2 AREA OF SOIL CONTAMINATION.. . . . . .. ........................, 4
3.3 MIGRATION OF CONTAMINATION..... . .,. """""""""""" 4
4.0 SUMMARY OF MAJOR ISSUES/CONCERNS/QUESTIONS/STATEMENTS
VOICED DURING PUBLIC COMMENT PERIOD. . . . . . . . . . . . . . . . . . . . . . . . . ., 4
4.1 CONCERN ABOUT DISCHARGING INTO THE CITY OF
SALISBURY SEWER SYSTEM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5
4.2 ESTABLISHMENT OF A FOURTH OPERABLE UNIT. . . . . . . . . . . . . . . . . . .. 5
4.3 ESTABLISHMENT OF A POINT OF COMPLIANCE WITH
ENFORCEABLE INSTITUTIONAL CONTROLS. . . . . . . . . . . . . . . . . . . . . . .. 7
4.4 ESTABLISHMENT OF A SITE CLEANUP LEVEL FOR
1,2-DICHLOROETHANE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ., 9
4.4 SELECTION OF THE MOST COST EFFECTIVE REMEDIAL
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RESPONSIVENESS SUMMARY
OPERABLE UNIT #3 PROPOSED PLAN
NATIONAL STARCH & CHEMICAL COMPANY SUPERFUND SITE
1.0 OVERVIEW
The development of this Responsiveness Summary is in accordance to the requirement set forth
in 40 CFR 300.430(f)(3)(i)(F). This community relations Responsiveness Summary is divided into
the following sections:
Section 2.0 BACKGROUND
This section discusses the Environmental Protection Agency's preferred
alternative for remedial action, provides a brief history of community interest, and
highlights the concerns raised during the remedial planning for Operable Unit #3
(OU #3 or OU3) at the National Starch & Chemical Company (NSCC or NSC)
Superfund Site.
Section 3.0 SUMMARY OF MAJ0R ISSUES/CONCERNS/OUESTIONS/STATEMENTS
VOICED DURING PROPOSED PLAN PUBLIC MEETING
This section provides a summary of issues/concerns and questions/comments
voiced by the local community and responded to by the Agency during the
Proposed Plan public meeting. "Local community" may include local
homeowners, businesses, the municipality, and not infrequently, potentially
responsible parties.
Section 4.0 SUMMARY OF MAJOR ISSUES/CONCERNS/OUESTIONS/STATEMENTS
VOICED DURING PUBLIC COMMENT PERIOD
This section provides a comprehensive response to all significant written
comments received by the Agency and is comprised primarily of the specific legal
and technical questions raised during the public comment period.
2.0 BACKGROUND
The Environmental Protection Agency (EPA) conveyed its preferred remedial alternative for OU
#3 NSCC Superfund Site, located in Salisbury, North Carolina in the Proposed Plan Fact Sheet
mailed to the public on July 15, 1993, and through an ad in The Salisbury Post and The Charlotte
Observer newspapers. The ads were published in the July 19, 1993 edition of these two
newspapers. A press release reminding the public of the forthcoming meeting was issued on July
30, 1993. The public meeting was held on August 3, 1993 at the Agricultural Extension Center
in Salisbury, North Carolina. The purpose of the meeting was to present and discuss the findings
of the OU #3 Remedial Investigation/Feasibility Study (RIIFS), to apprise meeting participants of
EPA's preferred remedial alternative for OU #3, to respond to any questions or address any
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OU 13 Nalicnal Starch & Chemical Company
ResponsiYwless Summaty
A-2
concerns expressed during the public meeting, and to take their comments and make them a part
of the official record. A copy of the transcript from the August 3 public meeting was placed in the
Information Repository for public reading. The Proposed Plan Fact Sheet, the newspaper ad, and
the press release all informed the public that the 30-day public comment period would run from
July 19 to August 17,1993. However, a request was made for a 30-day extension to the public
comment period. Consequently, the public comment period was extended to September 16,
1993.
No remedial alternative was presented for soils as this environmental medium will be addressed
in the forthcoming Operable Unit #4.
The alternative presented for addressing the contaminated groundwater included Altematives
GWP3B/GWL3B and GWP4B/GWL4B: This alternative permanently removes the contaminants
in the groundwater through groundwater extraction and on-site treatment through an air stripper
with controls on air emissions. The treated groundwater will be discharged into the City of
Salisbury's sewer system. The following activities are involved in this alternative:
.
Contaminated groundwater will be extracted from within and at the periphery of the plumes
emanating from the Area 2 and the treatment lagoon area via extraction wells and piped
to an on-site, above-ground trClatment process;
.
Treatment will consist of air stripping to achieve concentrations to meet discharge
requirements set forth by the City of Salisbury wastewater treatment system;
Long-term monitoring of the underlying aquifer; and
.
Implementation of a deed restriction on the NSCC property as an institutional control.
The alternative presented for addressing the contamination detected in the surface water and
sediment of the Northeast Tributary was SW/SE-2. This alternative requires long-term monitoring
of the stream as the proposed groundwater remediation system will reduce and eventually
eliminate the contamination discharging into the stream along with the groundwater.
The Risk Assessment indicates that neither the soils nor groundwater pose an unacceptable risk
to either human health or the environment under present conditions; however, these contaminated
environmental media could pose as an unacceptable future risk to both human health or the
environment. In addition, the remediation of the groundwater is warranted as the levels of 1,2- .
dichloroethane and a number of other chemicals are above applicable or relevant and appropriate
requirements (ARARs) established for these contaminants in the groundwater. For these
contaminants, the cleanup goals selected were Safe Drinking Water Maximum Concentration
Levels, State of North Carolina groundwater quality standards, and risk based concentrations.
Community interest and concern about the NSCC Site has fluctuated from moderate to high over
the past two decades. Awareness of and concern about the NSCC .Plant., not the Superfund
related hazardous wastes, were very high in the communities which are adjacent to and nearby
the "Plant". NSCC received considerable news media attention when it's Lumber Street Plant,
which is also located in Salisbury, North Carolina, experienced an explosion which destroyed a
section of the plant. In 1984, at the NSCC Cedar Springs Road Plant where the Superfund Site
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OU 13 Nalional SIBrd'l & Chemical eomp.,y
Responsiveness Summaty
A-3
is located, a production process reportedly boiled over releasing a vapor cloud containing acetic
acid. The vapor cloud reportedly injured vegetation for up to 1.5 miles from the plant.
A 1985 newspaper article indicated there were mixed feelings in the communities surrounding the
plant. Some of the residents believe that NSCC is a responsible company with an excellent
record and that NSCC will work with EPA and cleanup the dump. Other residents were
concerned about the effects on their health and believe their community has borne the brunt of
living near to NSCC. As stated above, the community has maintained a high level of awareness
and concern regarding NSCC as a result of the incidents reported in the media.
The following provides details on the accumulative community relations efforts conducted by the
Agency. A Community Relations Plan identifying a positive public outreach strategy was
completed in September 1986. As part of this initiative, Information Repositories including the
Administrative Record, were established at the Rowan County Public Library and in EPA, Region
IV Information Center in Atlanta, Georgia to house the Administrative Record for the Site. The
Information Repository and Administrative Record are available for public review during normal
working hours.
Fact sheets and public meetings were the primary vehicles for disseminating information to the
public. EPA sponsored a number of public meetings and released several fact sheets to keep
the public apprised of current activities, to help the community understand the Superfund program
and the public's role in the process, and to share information regarding the direction and technical
objectives of data collection activities at the Site. Only a few individuals from the community
attended the Proposed Plan public meeting. In addition to these individuals, one representative
from the news media, representatives from NSCC, and representatives from various government
agencies also attended the meeting.
3.0 SUMMARY OF MAJOR ISSUES/CONCERNS/QUESTIONS/STATEMENTS VOICED
DURING PROPOSED PLAN PUBLIC MEETING AND RESPONSES
This section summarizes the major issues and concerns expressed during the Proposed Plan
public meeting. Only four questions were asked during the public meeting. They related to:
.
Why was soil remediation alternatives left out of the Proposed Plan?
.
Area of soil contamination?
.
In what direction is the contamination migrating and has the contamination migrated off the
NSCC property?
A recount of the questions summarized above and the Agency's response can be found on pages
32-36 of the transcript of the Proposed Plan public meeting (Attachment A).
Summarized below are significant questions asked during the Proposed Plan public meeting:
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au 13 National Sta/'d't & Chemicaf CoITI!)8nY
ResponsMw\es1 Summary
A-4
3.1 SOIL REMEDIATION ALTERNATIVES
0:
What's wrong with the soil that you have to go back to the operation?
It's not what's wrong. NSCC needs to perform a more thorough evaluation of the soil
alternatives.
A:
3.2 AREA OF SOIL CONTAMINATION
0:
Where's the soil now?
A:
An overhead was used to show the extent of soil contamination.
3.3 MIGRATION OF CONTAMINATION
0:
Has any of the contamination left the soil yet? Left the property?
To the best of our knowlerfge, no.
A:
0:
Something in the paper about it traveling north; is that true?
A:
Its tending to follow the stream which flow in a northerly direction.
4.0 SUMMARY OF MAJOR ISSUES/CONCERNS/QUESTIONS/STATEMENTS VOICED
DURING PUBLIC COMMENT PERIOD
This section summarizes the major issues and concerns expressed during the Proposed Plan
public comment period. The major issues and concerns on the proposed remedy for OU #3
NSCC Site can be grouped into five areas:
.
Discharge into the City of Salisbury sewer system;
.
Establishment of a Fourth Operable Unit;
.
Establishment of a Point of Compliance with Enforceable Institutional Controls;
Establishment of a Site Cleanup Level for 1 ,2-Dichloroethane; and
.
.
Selection of the Most Cost Effective Remedial Alternative.
Below is each written comment received and the Agency's corresponding response in italicized
print. The comments below have been transcribed verbatim from the written set of
comments the Agency received.
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OU 13 National SIBtCtI & Chemical Company
ResponsiY8n8S1 Sunwnary
A-5
4.1 CONCERN ABOUT DISCHARGING INTO THE CITY OF SALISBURY SEWER SYSTEM
COMMENT #1:
RESPONSE:
This industrial user is subject to categorical OCPSF organics limits, and is
usually in compliance with our local limits for those compounds. However, the
application of supplementary limits to the discharge - fume toxicity, explosivity,
and human health criteria - could result in some limits being so restrictive that
this discharger may be unable to consistently meet those limits. If this occurs,
the potential exists that the remediation project could be halted until the system
is redesigned to meet the more stringent limits.
The City requests that the EPA Superfund Branch work and communicate with
the NPDES Permit Branch in an effort to develop and implement limits based
on more practical, alternative ways of assuring both worker safety and
collection system integrity. We feel that the existing methods may produce
limits which are unrealistic when compared to OCPSF limits or local limits
derived by traditional headworks methods. We request your assistance in
resolving this compliance issue.
Currently, IT Corporation which is NSCC's contractor, does not believe it will be
necessary to revisp. NSCC's existing discharge permit. However, in the event
after closer examination of all the data, it becomes apparent that the discharge
permit to the City of Salisbury sewer system will need to be revised due to the
additional loading created by the groundwater extraction system for OU #3, then
all entities involved, the Agency, North Carolina Department of Environment,
Health & Natural Resources (NCDEHNR), the City of Salisbury, the potentially
responsible party (PRP), and the PRP's contractor will need to work together
to develop and implement limits based on practical, alternative ways of assuring
both worker safety and collection system integrity. A determination on whether
or not the existing discharge permit will need to be revised cannot be made
until the Remedial Design stage at which time the actual loading rates and
volumes can be calculated.
4.2 ESTABLISHMENT OF A FOURTH OPERABLE UNIT
COMMENT #2:
For the reasons expressed in the enclosed comments of IT, we do not believe
that it is necessary to establish a Fourth Operable Unit. NSC has agreed to
perform the DNAPL test suggested by EPA and the State. We are prepared
to perform this test immediately following EPA's approval so that the results will
be available prior to issuance of the ROD. Thus, if the tests do not show the
presence of DNAPLs, we do not think a Fourth Operable Unit to address soils
should be required.
At a minimum, we think it is premature to establish a Fourth Operable Unit
unless and until such time as continued groundwater monitoring results indicate
that concentrations of contaminants do not significantly decrease. We suggest
that the ROD be written 50 as to require a Fourth Operable Unit at a later date,
only if necessary, following the analyses of sufficient groundwater monitoring
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OU 13 Naliona/ SIard1 & ChernicaJ Company
Responsiveness Summary
A-6
RESPONSE:
COMMENT #3:
results that would allow a determination of the effectiveness of a no action soil
alternative.
The need fora fourth operable unit was a mutually agreed upon decision
between the Agency and NCDEHNR. The decision was based upon the fact
that the June 21, 1993 FS report did not provide sufficient supporting and
defendable technical rationale for the elimination of soil remediation
technologies that could permanently remove the residual contamination from
the soil. Therefore, OU #4 FS will need to more thoroughly evaluate soil
remediation technologies providing sufficient rationale for the elimination and/or
retention of appropriate technologies that can address the soil contamination
at the Site.
Another concern which was highlighted during the review of the draft Proposed
Plan focused on the potential presence of either a free-phase or residual dense
non-aqueous phase liquid (DNAPL) in the soil in Area 2. The primary
contaminant at the NSCC site is 1,2-dichloroethane (1,2-DCA) which is a
chemical that can exist as a DNAPL. The presence of a DNAPL in either the
soils or aquifer can control the ultimate success or failure of remediation at a
hazardous waste slce. The testing procedures and findings of the hydrophobic
dye test conducted on September 22-23, 1993 shall be incorporated in the OU
#4 FS document. Currently, the Agency does not foresee the need for any
additional field work to be conducted as part of OU #4; hence, the June 2, 1993
RI report should suffice as the OU #4 RI report.
We disagree with the EPA for the need of another Operable Unit. Based on the
investigative data that has been collected the source of contamination of the
subsurface soils is well defined. In fact, the EPA has stated in the Proposed
Plan that "The OU3 soil investigation has generated ample information to
characterize the contamination, determine the source, and define the extent of
contamination in the vadose soil zone."
The EPA and the NCDEHNR have both expressed their concerns about the
presence of dense nonaqueous phase liquid (DNAPL), which they have used
as the basis for the establishment of OU4. The agencies want the OU3 FS
expanded to include more active remedial actions for the soil because they
suspect that DNAPL may be present in the soil and if the DNAPL continues to
release from the soil to the groundwater the groundwater remediation will not
succeed in cleaning up the aquifer. The data that has been collected to date
does not indicate that DNAPLs are present, but direct testing has not been
performed to refute their concern.
The NCDEHNR has recommended a field screening test using hydrophobic dye
to make the determination of the presence or absence of DNAPLS, which
NSCC has agreed to perform. The testing procedure along with the proposed
borehole location is provided as Attachment A. (This attachment has not been
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OU 13 National Starc:h & ChemlC8/ Company
ReSPOnsMlnesl Summary
A-7
RESPONSE:
incorporated into the Responsiveness Summary.) We feel that if the test results
show an absence of DNAPL there truly is no need for another operable, unit.
We continue to recommend long-term monitoring of the groundwater to
determine if no action is sufficient for the subsurface soils. If increased
concentrations of contaminants or no substantial decrease in concentrations of
contaminants are noted after 5 years of active groundwater remediation then
other remedial options may have to be considered.
As denoted in the Response to Comment # 2 above, it is the lack of supporting
technical rationale in the June 21, 1993 FS report for the elimination/retention
of the soil remediation technologies that is actually driving the need for revising
this document in OU #4. In other words, the OU #3 FS report failed to meet
the requirement set forth in Section 121 CERCLA. This section states, EPA
shall "conduct an assessment of...altemative treatment technologies, that in
whole, or in part will result in a permanent...significantly decrease in the toxicity,
mobility...". The FS report failed to discuss altemative treatment technologies
for soil. The FS report discussed only institutional controls and long-term
monitoring.
If a DNAPL is found to exist on-site, the Agency has found through experience
that it is more adVi:lntageous to remove the DNAPL directly rather than rely on
a pump and treat technology to remove the DNAPL. If necessary, the OU #4
FS report will need to address this issue.
4.3 ESTABLISHMENT OF A POINT OF COMPLIANCE WITH ENFORCEABLE
INSTITUTIONAL CONTROLS
COMMENT #4:
EPA should establish a point of compliance for remediation of the contaminated
plume that is, at a minimum, at the plume periphery rather than throughout the
plume. That the NCP permits a remedy to incorporate a point of compliance
that is a distance away from the source of groundwater contamination is not
disputed by EP A. This issue was raised recently in a lawsuit brought by
various states against EPA challenging EPA's use of the NCP in CERCLA.
Ohio v. EPA, 39 ERC 2065, US Ct App, DC (1993). There, the Plaintiff states
argued that in the preamble to the NCP EPA acknowledges that, while
"remediation levels should generally be attained throughout the contaminated.
plume, or at and beyond the adae of the waste manaaement area...!D,
alternative Doint of comDUance may also be Drotective of DubUc health and the
environment under site-sDecific circumstances: (underlines added) 40 C.F.R.
300.430(f)(5)(iii)(A). EPA did not challenge the states' interpretation of the NCP
in this regard. Rather, EPA's response was that". . . alternatives must in any
case be protective of public health and the environment: Ohio v. EPA. supra
at p. 2080. It is thus clear from the language of the NCP, and from EPA's
interpretation of the NCP in the Ohio case, that it is permissible to set a point
of compliance at the property boundary, the plume periphery, or any other
alternate point so long as it is protective of public health and the environment
-------
au ~ National Starc:tI & Chemical ~y
Responlivene81 Surnnwy
A-a
RESPONSE:
COMMENT #5
The NCP threshold criteria of overall protection of public health and the
environment is met at this site by setting such alternative point of compliance
at the plume periphery, especially when combined with institutional controls.
NSC is certainly agreeable to having a deed restriction recorded against the site
indicating that the plume of contaminated groundwater is not suitable for
drinking and prohibiting such use in perpetuity. Such deed restriction would run
with the land and would thus legally prevent drinking water wells from being
established in or near the plume. Moreover, NSC is willing to support the
adoption by the City of Salisbury of an ordinance that would also prohibit such
use of the groundwater unless it is demonstrated to meet drinking water
standards. Such undertakings on the part of NSC could be incorporated into
an enforceable Consent Decree in which NSC would agree to notify EPA and
the State of North Carolina in the event it ever sold the site to a third party.
Stipulated penalties could also be incorporated into the Consent Decree to
ensure the enforceability of such institutional controls.
It is doubtful that a site cleanup level of 5 ppb (and certainly of 1 ppb) for
, ,2-dichloroethane ("DCA") throughout the entire plume could ever be met.
Establishing an alternate point of compliance of the plume periphery, along with
the institutional controls mentioned above, or other institutional controls which
NSC would be wi:::;'Ig to consider, meets the threshold NCP requirement of
overall protection of the environment and is consistent with EPA's interpretation
of the NCP as articulated most recently in Ohio v. EPA. supra.
40 CFR 300.430(a)(1 )(iii)(F) states "EPA expects to return usable ground
waters to their beneficial uses wherever practicable, within a timeframe that is
reasonable given the particular circumstances of the site. When restoration of
ground water to beneficial uses is not practicable, EPA expects to prevent
further migration of the plume, prevent exposure to the contaminated ground
water and evaluate further risk reduction." And in accordance to Section 5.2. 1
of EPA's Guidance on Remedial Actions for Contaminated Ground Water at
SUDerfund Sites (EPA/540/G-88/003), "The area of attainment defines the area
over which cleanup levels will be achieved in the ground water. It
encompasses the area outside the boundary of any waste remaining in place
and up to the boundary of the contaminant plume." Furthermore, it states that
"...if the source is removed, the entire plume is within the area of attainment. "
Based on the above assertions, the Agency elected that the entire plume be the
point of compliance.
The proposed plan did not discuss a compliance point nor do the agencies
accept the concept of a compliance point for CERCLA, when it is commonly
used under RCRA. However, the agencies have no problem associating
various laws, acts, regulations to determine cleanup standards (i.e. ARARS).
The final rule, 40 CFR 300.430 (f)(5)(iii)(A), provides the following statement
"performance shall be measured at appropriate locations in the groundwater...".
The groundwater plume is considered the waste management area, therefore
the point of compliance should be at the edge of the plume.
-------
OU t3 National S1ardI & Chemical Comp8'Iy
ReSponsiwnesl SUmmary
A-9
RESPONSE:
The groundwater plume boundary has been well defined as depicted in figures
in the RifFS documents. The area of groundwater contamination is well within
the property boundaries, which offers the agency with a large buffer zone
between the compliance point and the nearest receptors. An integral part of the
establishment of compliance points is the implementation of institutional
controls. Institutional controls are required at this site in order to prevent future
human exposure to contaminants remaining within the waste management area
(Le. groundwater plume upgradient of the compliance points).
The agencies have expressed concern over their inability to enforce institutional
controls. There are many options available to the agencies such as: deed
restrictions, local ordinances, fencing, etc. The enforcement terms of for these
controls can be identified as part of a consent decree, administrative order,
contract, etc. National Starch should make a recommendation to the agency.
The Agency maintains that the point of compliance will be throughout the entire
plume of contamination. Refer to the response for Comment #4 for the
supporting rationale.
4.4 ESTABLISHMENT OF A SITE CLEANUP LEVEL FOR 1.2-0ICHLOROETHANE
COMMENT #6:
RESPONSE:
As discussed in the enclosed comments of IT, the site cleanup level for DCA
should be set at 5 ppb (at the point of compliance, as discussed above) which
is the federal primary drinking water standard. Such level satisfies the NCP
criteria of overall protection of public health and the environment The State of
North Carolina drinking water standard of .38 ppb, while relevant, is not
appropriate based on problems with the accuracy of detecting concentrations
of DCA at that level and it is not applicable to the contaminated groundwater
plume here since such groundwater is not the source of drinking water supplies.
EPA has proposed a level of 1 ppb for Operable Unit Three in recognition of the
problem of accurately detecting DCA at levels of .38 ppb. However, EPA has
previously determined that the practical quantitative limit ("POl") (defined as the
lowest level that can be reliably achieved within specified limits of precision and
accuracy) is 5 ppb for all volatile organic compounds except vinyl chloride.
Federal Register, Vol. 52, No. 130, July 6, 1987. We do not believe there Is
any basis for establishing a level of 1 ppb for DCA as an ARAR at this site. To
the extent that any level other than the federal drinking water standard is
deemed by EPA to be an ARAR, we believe such ARAR should be waived and
we accordingly request such a waiver. We do not believe that a level of 1 ppb
of DCA can be demonstrated by EPA to be applicable to the conditions at this
site, nor is it technically achievable since it is below the pal as determined by
EPA.
40 CFR 300.400(g)(4) states, "Only those state standards that are promulgated,
are identified by the State in a timely manner, and are more stringent than
federal requirements may be applicable or relevant and appropriate". The state
-------
OU 13 National StardI , Chemical Company
Responsiveness Summary
A - 10
COMMENT #7:
RESPONSE:
groundwater quality standard for 1,2-DCA is 0.38 jJg/l as specified in North
Carolina Administrative Code (NCAC) 15-2L.0202(g). However, NCAG 15-
2L. 0202(b)(1) allows the state groundwater quality standard to be raised to the
detectable concentration. Consequently, the Agency raised the groundwater
performance standard for 1,2-DCA from 0.38 jJg/l to 1.0 jJg/l as 1.0 jJg/l is the
detection limit for 1,2-DCA under the drinking water analytical protocols, EPA
method 524.2. Based on the Superfund Analytical Methods for Low
Concentrations Water for Organic Analysis for the Contract Laboratiry Program,
dated June 1991, the quantitation limit for 1,2-DCA is set at 1 jJg/l.
40 CFR 300.430(f)(1 )(ii)(C) provides the grounds for invoking a waiver. Based
on the Agency's evaluation on the request for a waiver to the State's
groundwater quality standard (NCAC 15-2L.0202), the Agency concluded that
the request does not satisfy any of the specified grounds for invoking a waiver.
The federal MCL for 1 ,2-DCA is 5 ppb. The NCDEHNR groundwater standard
for 1 ,2-DCA is 0.38 ppb. IT has presented arguments in the past against using
the state standard based on the impracticability of accurately measuring the
concentration of 1 ~-DCA at that level. Based on this argument, EPA has now
proposed a cleanup standard of 1.0 ppb. However, this is in conflict with the
evaluation that was conducted by the EPA for the establishment of the MCL.
For the establishment of MCLs the EPA assesses a range of factors such as:
the availability and performance of Best Available Technology (BAT), the cost
of these technologies, the availability and reliability of analytical results, and the
resulting health risk (for carcinogens 10-4 to 10-6 is the acceptable range). As
part of the assessment for proposing the MCL for 1 ,2-DCA, the EPA determined
that "the costs associated with the additional removals, Le., from 0.005 mgll to
0.001 mgll, are not warranted", therefore, the MCL was established at 5 ppb
(Federal Register, Vol. 52, No. 130, July 6, 1987).
The EPA proposed cleanup standards are established for drinking water
supplies. National Starch plans to implement deed restrictions and possibly
have the City of Salisbury establish an ordinance so that the installation of
drinking water wells within the plume area will not be allowed. Based on the
arguments presented, we feel that the cleanup level for 1,2-DCA should be 5
ppb.
Although the argument set forth in this comment is straightforward, it does not
address the ultimate reason why the Agency selected a performance (clean-up)
standard of 1 microgram per liter (JJ(JA) or 1 part per billion (ppb) for 1,2-DCA.
To have selected anything else (i.e., the maximum contaminant level (MCL) for
1,2-DCA) as requested by this comment would have resulted in this Record of
Decision (ROD) in being out of compliance with the law. 40 CFR 300.400(g)(4)
states, "Only those state standards that are promulgated, are identified by the
State in a timely manner, and are more stringent than federal requirements may
-------
OU 13 Nalional SIarch & Chemical Compa'Iy
Responsiwness Summary
A - 11
be applicable or relevant and appropriate ". The state groundwater quality
standard for 1,2-DCA is 0.38 pgt1 as specified in NCAC 15-2L.0202(g).
However, NCAC 15-2L.0202(b)(1) allows the state groundwater quality standard
to be raised to the detectable concentration. Consequently, the Agency raised
the groundwater performance standard for 1,2-DCA from 0.38 pgt1 to 1.0 pgll
as 1.0 pgll is the detection limit for 1,2-DCA under the drinking water analytical
protocols, EPA method 524.2.
4.4 SELECTION OF THE MOST COST EFFECTIVE REMEDIAL ALTERNATIVE
COMMENT #8: For the reasons discussed by IT, we believe that vapor-phase carbon
adsorption should be selected by EPA as the preferred remedial alternative
based on cost-effectiveness.
RESPONSE:
COMMENT #9:
RESPONSE:
Both the vapor-phase carbon adsorption technology and the ,fume incinerator
technology achieve the same degree of protection and treatment of the
emissions from the air stripper. As directed by 40 CFR 300.430(f)(1 )(ii)(D), the
Agency should select the most cost effective alternative. Based on the
information providp.d in Comment #9, the Agency concurs with the request
stated in this comment and has selected vapor-carbon adsorption as the choice
of treating the emission generated by the air stripper.
Upon further review of the cost estimates provided in the FS it became
apparent that the O&M costs for vapor-phase carbon adsorption did not take
into account the reduction in groundwater concentrations over time. Using the
results of the contaminant fate and transport model (FS Appendix D) the
depletion rates for 1 ,2-DCA were estimated. Using the depletion rates and
starting with an assumed average concentration of 55,000 ppb of 1,2-DCA in
groundwater, the estimated vapor-phase carbon usage was calculated. The
cost was then estimated based on the total amount of carbon required for 15
years of treatment. Therefore, the revised estimate for Alterative GWL3A
Lagoon Area Groundwater (Extraction, Air Stripping, Vapor-Phase Carbon) is
$2,612,000 and the revised estimate for Alterative GWP3A Plant Area
Groundwater (Extraction, Air Stripping, Vapor-Phase Carbon) is $1,814,000.
The combined total is approximately $480,000 less than was reported in the
FS cost estimate for the same Alternatives and is approximately $,107,000 less
than the combined total for the same alternatives using fume incineration.
Therefore, we recommend that the agency select vapor-phase carbon
adsorption over fume incineration.
The Agency appreciates the above information and as specified in the response
to Comment #8, concurs with the request to change the treatment technology
for the emissions from the air stripper from fume incinerator to vapor-phase
carbon adsorption.
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ATTACHMENT A
TRANSCRIPT OF PUBLIC MEETING
-------
NATIONAL STARCH AND CHEMICAL COMPANY
SUPERFUND SITE
GROUNDWATER REMEDIATION FOR
OPERABLE UNIT NUMBER 3
7:00 P.M.
August 3, 1993
Salisbury, North Carolina
PROPOSED PLAN PUBLIC MEETING
. ~@[P)W
[~"r~tt£ [aurl lUparling, ]Jnr.
Joat
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AgggABAH~g~
Ms. Diane Barrett
Community Relations Coordinator
United States Environmental Protection
Region IV
345 Courtland Street, Northeast
Atlanta, Georgia 30365
Agency
Mr. Jon Bornholm
Remedial Project Manager
Superfund Remedial Branch
Mr. Winston Smith
Groundwater Expert
'* '* '* '* '* '* '* '*
IHRg!
Paqes
Comments by Ms. Barrett
Comments by Mr. Bornholm
4 - 9
9 - 32
Public comments
32 - 33
'* '* '* '* '* '* '* '*
-------
This is the proposed plan public meeting for
the National Starch and Chemical Company Superfund Site in
Salisbury, North Carolina, conducted before Shannon S.
McGilberry, Certified Verbatim Reporter and Notary Public,
at the Agricultural Extension Center, 2727 Old Concord Road,
Salisbury, North Carolina, on August 3, 1993, beginning at
7:00 P. M.
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4
1
2
MS. BARRETT:
Well, I want to welcome you tonight.
My name is Diane Barrett; I'm the Community
3
Relations Coordinator for the State of North
4
Carolina for our Superfund sites in this State.
5
Tonight's meeting is to present to the public the
proposed alternatives for treating groundwater at
6
7
this site, at the National Starch and Chemical
8
9
Company Superfund Site.
I'd like to introduce to
you our other people from Atlanta.
Mr. Jon
10
11
Bornholm, Jon please stand.
He is the remedial
project manager for this site and then Mr. Winston
12
13
Smith; he is our groundwater expert.
I hope each
of you have availed yourselves of the literature
14
15
out front as you came in as well as signing up.
This literature will give you a lot of information
16
17
about what we're talking about tonight, so that
will help y'all make a well informed decision on
18
19
The public comment period
what we're doing here.
for this particular proposed plan began on July
20
21
the 19th and will end at midnight August the 17th.
This is also a required meeting by our circle of
22
23
law and we have a court reporter here and she will
be taking the transcript from this meeting.
50
24
2S
when it comes to our public comment period, if you
would please $tand and give your name 80 that she
-------
1
can get it for the record, we would appreciate it.
2
3
I wanted to give you just a brief run down of
the community relations activities that have
4
happe..;d so far at this site.
First of all, let
5
me ask how many of you have ~~en to one of these
meetings before regarding this particular site and
6
7
are familiar with Superfund?
Are y'all familiar
8
with Superfund?
Okay.
9
First of all, at any site after it's first
10
11
discovered, and this site was investigated and the
12
proposed in the national priorities list and then
finalized in October of 1989, and the national
13
14
priorities list made this site eligible to be
funded for remedial design work through our
15
16
Superfund money.
The Superfund money is a tax
that is levied against chemical and oil producing
companies and the monies there are put in a fund,
17
18
and as the Superfund work progresses and we get
into the remedial design and action stages of a
19
20
process, the monies are used to conduct the
21
22
activities if there are not viable people to pay
for the work.
23
24
When we first began, after the site was first
listed on the national priorities list, the agency
25
conducted interviews here in the community to find
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~
~
1
2
out what the community concerns were and then we
prepared what we call our -- a community relations
3
plan that addressed the concerns of the
4
communities and how we would endeavor to keep them
5
informed.
Now, we do that through such things as
6
fact sheets, news articles, telephone calls, we
7
have a one-eight-hundred number, for your
8
convenience, to call us.
It is listed in the fact
9
We also have set up a repository which
sheet.
10
11
houses all of the documents that have been
developed that give us reports on making our
12
13
decis~ons on how to conduct the remedial design
activities for the site and making a selection of
14
which alternatives to use.
This repository is in
15
the Rowan County Public Library in downtown
16
Salisbury.
17
When we first started our interviews, a
18
19
mailing list was also developed at the time, and
then from each meeting thereafter, the names of
20
21
those who attended have been added to our mailing
list so that we can make sure that those
22
23
interested do receive information.
On September the 4th, 1985, the first meeting
was conducted here and that there were about sixty
24
25
people, I think, that attended that meeting, and
-------
1
2
that was just the beginning of meetings.
At that
time, too, the remedial investigation began and
3
that identifi
. the nature and extent of the
4
contamination.
This particular meeting covers
5
6
groundwater at the site.
As part of the remedial
investigation, a risk assessment is conducted and
7
this evaluates and identifies any risks posed by
8
specific chemicals.
There are six fact sheets out
9
there in the entrance way covering. various
10
11
contaminants of concern.
The major contaminant of
concern, though, is what we call 1,2-DCA, which is
12
Dichloroethane.
This is a major contaminant of
13
14
concern that we're addressing.
After remedial
investigation is conducted, that sometimes can
15
last a year to two years because extensive
16
sampling and analytical work is done, and
sometimes we may have to go out a second time to
17
18
gather mor~ data if we feel like we have not been
19
20
able to get enough at the time.
Then the
feasibility study begins.
This goes through
21
22
various alternatives that can be utilized to treat
the contaminants that are at the site, and this
23
24
also supports all of our responses to the
contaminants and the concerns that are listed in
25
our investig~tion.
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~
1
2
After the feasibility study has been
completed, we are at the point where we are now,
3
with the proposed plan fact sheet and our public
4
meeting.
These meetings, or this period, carries
5
a thirty-day public comment period and if
requested, it can be extended another thirty days.
6
.7
8
Once this is completed, when the comment period
ends, a remedy will be selected.
That remedy is
9
selected based on all the documentation that we
10
have received, plus all public comments that we
11
get from the public.
A record of decision is
12
13
recor~ed and announcing the selection that has
been made for treatment of the contamination at
14
the site.
15
An announcement will appear in an area
16
newspaper informing the public of the selection as
well as a regular decision fact sheet will be
17
18
prepared giving more detail into the alternative
that was selected so that it gives the public a
19
20
21
better understanding of what's going on.
Hopefully tonight, too, through Jon's
explanation of everything that you'll have a good
22
23
understanding of what we're proposing, but we've
24
25
got some good slides.
This is .the Superfund process.
Any time
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,
1
2
throughout that process community relations are
conducted and down below is a list of the various
3
4
activities that we undertake in keeping our public
informed.
There is a technical assistance branch
5
6
that is offered at each Superfund site for the
affected community, and that technical assistance
7
branch allows the community to organize into a
nonprofit unit and then to contract to have a
8
9
consultant come in and help them understand and
decipher all the technical explanations and help
10
11
them have a more active part in the decision
12
makin: process regarding the site.
Right now,
13
14
looking at this chart, we are at step five, the
public comment period, and we really request your
15
16
This is your site; you live here, we
comments.
don't, and we need to know what really affects you
17
18
and we would appreciate your comments.
I want to
turn the meeting over now to Jon Bornholm who will
19
20
go through the alternatives that have been
proposed in the fact sheet.
attention.
Thank you for your
21
22
MR. BORNBOLM:
Thanks, Diane.
Just a brief word
23
about myself.
I've been a Remedial Project
24
25
Manager for the Superfund program since 1984.
conducted th~ 1988 public meeting here in'
I
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.'"
1
2
Salisbury on the first operable unit in lieu of my
colleague who was on maternity leave.
Hopefully
3
everybody picked ~p a handout that looks like
4
this; it's about twenty pages long.
This is
5
6
basically all the overheads I'll be going through
tonight.
Some of them I'll read through quickly
7
8
because you have a copy of them here and you can
look at them more in detail at your own leisure.
9
10
But first of all, what I'd like to. do first is
just go through the history of the site just so
that everybody is brought up to date as to where
11
12
we'rE: at today.
13
14
The first figure that shows is the
approximate location of the site in Salisbury, and
15
16
moving into the background of the site.
It was
first owned by Proctor Chemical which was then
been acquired by the present owner, National
17
18
Starch & Chemical Company, who continue to operate
19
20
the plant today.
It is an active facility.
As
Diane alluded to before, the site was proposed,on
21
22
the National Priorities List in 1985.
It was'
reproposed in 1988 and was finalized on the list
23
24
in 1989.
Sites that score below a hazardous
ranking score of 28.5 are not added to the list,
25
the National.priorities List.
Everything above
-------
1
2
28.5 is eligible to be placed on the National
Priorities List and the individual scores for the
3
ranking process basically the surface water
pathway and air pathway at the time of assessment
4
5
scored zero and the groundwater pathway was what
6
scored and resulted in the site being put on the
7
National Priorities List.
8
9
The first operable unit began in 1986 with
the National Starch and Chemical Company signing a
10
administrative order on consent with the Agency,
11
12
basically agreeing to do the work that we
estab:ished for them to do and the rest of the
13
information pertains to the work done as part of'
14
operable unit number 1.
The remedial
15
16
investigation looked at the air, the surface
water, the ground water, as well as the soils.
17
The proposed plan fact sheet was distributed to
18
19
the public and we held our public meeting.
Back
then the public comment period was only three
20
21
weeks long.
Since that time the Superfund law has
been revised to a four-week period or thirty days
with a potential extension of an additional thirty
22
23
days at the request of the public.
That record of
24
decision was signed on September 30th, 1988 for
25
operable uni~ one.
And I'll -- there's another
-------
1
2
figure that's kind of details where all these
3
operable units are on the site.
Operable unit two was initiated back in '89.
4
Basically what the first record of decision did
5
was it identified the -- the information said that
6
7
the groundwater and soil was contaminated, but the
Agency wasn't comfortable with the information
8
9
with respect to the soils contaminated, so the
Agency directed the potential responsible parties
to go back and do an additional investigation
10
11
which on operable unit two consists of.
Again, we
12
13
had a proposed plan fact sheet that was issued to
the public.
We had our public meeting and then
14
15
the record decision was signed in September of
1990.
As an operable unit number -- as in the
16
17
record decision for operable unit one, this record
decision for operable unit two also required
additional work by the potentially responsible
18
19
parties and this became operable unit three.
And basically where we're at right now with
20
21
regard to operable unit three, the work was
basically started in 1991 with the remedial
22
23
investigation being concluded in March of this
24
25
year, at least the field work was.
The proposed
plan was dist;.ributed on JU,ly.
Tonight is the
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1
public meeting for that proposed plan and then the
2
3
public commentary is -- it began, as Diane.said,
on July 19th.
4
5
Operable unit three consists of two areas.
The plant area, which is the active facility
itself, which consists of area number 2, which
6
7
8
includes the reactor room, the tank room, the raw
materials bulk storage room, and the warehouse,
9
10
and as well as the buried terra cotta pipe lines
from the reactor room to their treatment lagoons.
11
And that the second area of investigation as part
12
13
of oporable unit number 3, were the lagoons
themselves.
14
15
I'm going to try to put it all together for
This figure -- operable unit number 1 deals
you.
16
with groundwater flowing in this direction.
50
17
down here, which is basically off this figure,
groundwater contaminated this area and is being
18
19
dealt with by operable unit number 1.
unit number 2 basically deals with the
Operable
20
21
contaminated soils in the trench area, and then
22
23
operable unit three, which is what we are talking
about tonight, here is area number 2 which is the
24
25
actual plant, and here is the lagoons.
Okay.
T~e remedial investigation, again,
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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
looked at soils, groundwater, surface water and
sediment.
As far as the soils, basically ~e tried
to define three things in the remedial
investigation for each environmental media.
We
tried to characterize the contamination, what
contaminants are out there and at what
concentration.
We tried to define where that
contamination is coming from and then how far has
it migrated from the source.
Basically what we
found is that we had fourteen different volatile
organics in the soils, with 1,2-DCA, or 1,2-
Dich]~roethane being the main contaminant at the
site.
As far as the source, the lagoons were
unlined prior to 1983.
After that time they were
excavated and lined with concrete liners, so they
were acting as a source prior to 1983 and then the
terra cotta piping or pipelines coming from the
treatment -- or the active facility leading to the
treatment lagoons is the other source on the site.
And then as far as the extent, basically what
the data shows is that it has basically stayed
close to where the source evolved.
There was some
migration but all contaminants remain on site.
And then try to put it in a figure, these are the
concentrations of 1,2-Dichloroethane in and around
-------
1
2
area number 2, which is right here (indicating on
document), and arranges the concentration range,
the highest concentration was one million six
3
4
hundred thousand parts per billion down to non-
5
detect.
And again, these lines out here show the
6
range of concentrations and then move further away
7
from the source, the levels of concentration
8
decrease to non-detect.
9
And then as far as the lagoon area, again,
this figure is based on concentrations of 1,2-
10
11
Dichloroethane.
Again, we have a little hot spot
12
right here, per se, and then as we move away from
that area, the levels decrease again down to non-
13
14
15
detect; and that's soils.
The other -- and then when we look at acetone
16
we tried to put the concentration of acetone on a
17
figure again.
We have the same general area of
18
location of contamination near the lagoon right
19
20
here (indicating on document), as we did with 1,2-
Dichloroethane and basically the same for area
21
22
number 2 and this area, and then in this area.
where 1,2-Dichloroethane encompassed this whole
23
24
area.
As far as groundwater, again, we had those
25
three object~ves:
one, to characterize what was
-------
- -
1
2
in the groundwater, the types of contaminants and
their concentrations.
Number 2, to find out the
3
4
source of where that contamination was coming from
and then also to define the extent of
5
6
contamination.
How far has that contamination
migrated.
In the groundwater we found sixteen
7
different volatile organics.
Again, the major
8
9
compounds were 1,2-Dichloroethane and acetone.
As
you would assume, the source for soils would be
the same source for groundwater and that was the
10
11
12
lagoons prior to being lined and the terra cotta
pipel~ne.
13
14
As part of the remedial investigation we also
15
tried to define the geology of the soils so we
could determine which way groundwater is flowing,
16
how quickly it is flowing and what this thing
17
18
shows is a cross section of the geology of the
site,
(indicating on document) here being the
19
20
northeast tributary, the plant area being
approximately right in this area, and below the
21
22
plant we have what is called saprolite, which is
weathered bedrock, basically typical soils for
23
24
this area.
Down underneath the bedrock,
25
underneath the saprolite we have fractured
bedrock, and. then below the fractured bedrock we
-------
1
2
have constant bedrock, which basically there's no
fractures and there's no groundwater flowi~g
3
throug~ that area.
4
To try to put this all in some type of
meaning and try to define the concentrations and
5
6
the extent of contamination.
Again, as I
7
mentioned, the primary contaminant is 1,2-
8
9
Dichloroethane, so most of these figures are based
on the concentrations we found at the site of 1,2-
10
11
Dichloroethane.
As with the soils, again,
Okay.
we have basically two hot spots on the site.
One
12
that'~ near the lagoon area and the second one is
13
within the area number 2, which is the active
14
facility.
Groundwater is predominantly moving
15
16
towards the northeast tributary in this direction
(indicating on document).
And this figure
17
basically shows the concentration of 1,2-
Dichloroethane at the water table.
18
19
Okay. This figure, again, is based on
concentrations of 1,2-Dichloroethane in the
20
21
groundwater and the saprolite, which is below the
22
23
water table, and again, it's basically showing the
same thing.
We have a high concentration of
24
25
contaminants in both the lagoon area and the plant
area.
-------
1
2
Then the third figure is the range of
concentration in the bedrock zone, the fractured
3
4
Again concentrations are again --
bedrock zone.
the higher concentrations are again right in those
areas where the lagoons and the plant are.
5
6
The important thing, which I should have
7
8
mentioned on all these figures, is that we do have
delineation or a definition of the extent of the
9
plume, which is defined by these dotted lines and
basically the information is showing that the
10
11
contaminants in the groundwater are not migrating
12
13
off the property.
That's an important
consideration.
14
15
Then the last environmental media that was
investigated for this operable unit was the
16
surface water and sediment in the northeast
17
18
tributary.
We only found two organics, two
volatile organics there.
Again, 1,2-
1~
20
Dichloroethane and acetone.
The source is the
groundwater, the contaminated groundwater, is
21
22
discharging into that stream and it extends just
downgradient of the plant area itself.
Md
23
24
basically the next two figures define the extent
of contamination in that stream with the
25
concentratio~s being the numbers in parenthesis,
-------
1
2
with the flow and the stream going this way.
Again, there were no detections of these
contaminants upstream of the plant, that's what
3
4
the "ND" stands for, non-detect.
Then as you get
5
6
parallel to the plant, you get detection,
concentrations of contaminants.
As you move
7
downstream, again, those concentrations falloff
8
9
until you eventually reach non-detect.
During one sampling event at the site,
10
11
samples reflected along the entire reach of the
stream down to the property boundary and at that
12
13
partic-11.lar point no detections were -- no
contaminants were detected leaving the site.
That's -- this map basically is for surface
14
15
water and then this figure is for sediment, which
16
17
Upgradient we
basically follows the same pattern.
have non-detect, just parallel to the site we have
18
19
some detections, and then as you move down
gradient, the concentrations decrease until you
20
21
reach non-detect.
We tried to lump this all together as to
contaminants detected, the total list of
22
23
contaminants detected, is this first table here,
24
25
table 1-1.
It lists all the organics that we've
detected and.which environmental media they were
-------
1
2
detected in, soil, groundwater, surface water or
sediment.
The first numbers basically are. the
3
ranges and then the numbers in parenthesis are the
4
5
frequency of detection.
How frequently did they -
- were those contaminants detected.
And again,
6
let me just point out 1,2-Dichloroethane and
7
acetone were the two primary contaminants at the
site.
8
9
10
Using all this information, we go into
Okay.
a risk assessment.
In order for there to be a
11
12
risk, two pieces of the puzzle have to be present.
One, ~here has to be a pathway.
Although you
13
14
might have a contaminant here, if you have no
pathway from that source to a population or
15
something, there cannot be a risk because there's
16
And then the second piece of that
no exposure.
17
18
puzzle is the chemical has to have some toxicity
associated with it.
If you have a source of
19
20
water, water is not toxic, although it is a
pathway, it wouldn't cause risks because water .in
21
22
itself does not have any toxicity associated with
it.
23
24
And not to try to confuse the issue,
basically when we talk about risks, we use
25
numbers.
-- in
our -- in the EPA we use
We ,use
-------
,
.. -
1
2
the term "unacceptable risk," and that is when the
risk is greater than one times ten to the minus
fourth or one of ten thousand people may be
3
4
adversely affected by contaminants.
And then if
5
6
it's a noncarcinogenic chemical we use a hazard --
what's called a hazard index and if the hazard
7
index is greater than one, then that contaminant
8
9
in itself poses an unacceptable risk.
Not that I'm going to go through this, but
basically, the important issue here that I want to
10
11
12
point out is one, the site does not pose a current
risk to the public health.
There are future
13
unacceptable risks associated with the site and.
14
15
these are based on scenarios developed by the
Agency.
And there are three scenarios that would
16
present an unacceptable risk to human health.
17
18
First would be if a site was developed as a
residential area and those folks would build their
19
20
own wells and use the groundwater under the site.
21
22
That would pose an unacceptable risk and these
would be the numbers associated with that risk.
The other -- another risk would be a child playing
23
24
in surface water, sediment or spring.
Then the
third one would be exposure to subsurface soils.
25
If you're bu~lding a foundation, gardening or
-------
,
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
something -- the gardening would be -- you'd have
to dig real deep though, the soils, that wo~ld
pose an unacceptable risk.
But the main point is, that I want to point
out is that there is no current risk posed by the
site based on our information collected to date by
the contaminants present in the soil or the
groundwater.
The groundwater does not pose a risk
because there's no pathways to date, meaning that
there are no people using that contaminated
groundwater for probable use, for drinking water.
~~d as far as -- another part of the risk
assessment is environmental risks.
Basically,
what this -- the key here is that it's basically
inconclusive to date, because the headwaters of
the northeast creek are just above the property.
There's not much environment for the bionic
organisms to survive in, so they conclusive -- it
could not be proven conclusively that the
discharge of 1,2-Dichloroethane into the stream
along with the groundwater is causing an
environmental -- an adverse environmental effect.
The next table lists what the Agency has
identified as performance standards or our clean
up goals to b~ obtained by ,the groundwater
-------
1
2
remediation.
There are several changes here, they
are in the handouts, so let me point those. out.
One, I believe the State has proposed seven
3
4
hundred and I believe that's up for comment right
5
now and it has not been promulgated.
If it's not
6
promulgated by the time that this record decision
is signed then the clean up goal will be thirty-
7
8
9
five hundred because that is the value that's
promulgated today.
Another change, I believe,
10
11
there's a typo, is Tetrachloroethane.
The State
standard is point seven.
I think it says seven in
12
13
the r.~ndout that you have.
Because the
quantitation limits or analytical methods, that
14
moves up to one, that's the lowest level that we
15
16
can detect on parts per billion.
And I think this
17
70 here is also a proposed State clean up goal out
for public comment and this 70, I think, is
18
missing and that is already promulgated, that's
already been established as a State clean up goal.
19
20
What the law, Superfund Law, requires us to do is
21
22
to select the most stringent clean up goals.
50
basically what I tried to do, is I tried to list
the federal clean up goals here, the State clean
23
24
up goals here, and whichever is the smallest
number, the most stringent clean up standard is
25
-------
2-*
1
the one that's listed in the shaded area and that
2
3
will be the one that will be included into the
record decision as the clean up goal or
4
performance standard.
And then the other
5
difference is the addition of that number, which
6
again is the proposed State clean up.
It's a
7
rarity when they go up in concentration rather
than going -- rather than decreasing.
And then this is the last half of that table.
8
9
10
11
As you may notice, this table has fewer compounds
than that table 1-1, that lists all the
12
13
contaL.inants that were detected.
Basically the
reason is that the other contaminants did not pose
14
15
a risk.
These are the contaminants ~hat were
detected on site that posed an unacceptable risk.
16
And as far as -- as far as the surface water, we
17
18
really don't have any established clean-up goals
that are written into laws.
We use what is called
19
20
"TBC's," to be considered.
They're not
enforceable by any law or any faction, but the
goal is to achieve a level of two hundred thousand
21
22
micrograms per liter in the surface water, and
23
24
that should be three thousand, I believe, a little
25
typo there, with range concentrations from. two to
three thousan~, so we're just above that goal
-------
- -
1
here.
2
3
Basically that's the end result of the.
remedial investigation, with all that information.
Using that information we go on to the feasibility
4
5
studies.
Basically, all the feasibility study is
6
is a screening process going step-wise, looking at
7
the cookbook range of remedial alternatives or
8
9
techniques that we could use at the site and then
through a process of screening that we narrow that
list down to a shorter list that we take into a
10
11
detailed analysis.
:~ the first step of the process is to
12
13
eliminate all those techniques that just won't
14
15
work at the site.
Then following that we use the
second step which is the screening process and we
16
use three criterias to evaluate those remaining
17
technologies to eliminate those that aren't worthy
18
19
of passing through the process.
And the next
20
couple of slides basically just show the cook --
this is basically the cookbook list of all the
21
22
technologies that were initially considered and
the shaded areas are those that were rejected, and
23
24
then one more page to that entire table.
And then
in the right hand column under "Comments" is the
25
rationale fo~ rejecting the technologies.
That's
-------
~
~ -
1
2
the first screening; if the technology just is not
implementable at the site, it gets thrown out.
3
The second step of that screening process is
4
a little bit more detailed.
Again, we are looking
5
6
at the three criteria, institutional
implementability, effectiveness and cost.
And in
7
this table the ones that are -- the blocks that
8
9
are encircled in bold are the ones that were kept.
Again, the rationale as to why each of these
10
alternatives are either kept or rejected is stated
under the criteria.
11
12
nnd then once we get through that screening
13
process we develop our remedial alternatives.
The
14
15
first step is to combine appropriate technologies
into remedial alternatives to address the
16
17
contaminants in each of the environmental media
that are of concern.
In this instance we are
18
19
looking at groundwater and surface water.
AAd
then, again, we use the same three criteria .to
20
21
look at the remedial alternatives to evaluate
them.
And those alternatives that survive, those
22
23
remedial alternatives, that survive that screening
then go through a detail evaluation using these
24
25
nine criteria.
To date, only seven criteria have
been used.
~he public comment period incorporates
-------
..
1
2
these last two, the State acceptance, as well as
the community acceptance, and that's the p~imary
3
4
reason why we're here tonight.
All of these --
the special criteria and the evaluating criteria
5
6
have already been done and that was done in part
by the feasibility study efforts.
And then the
7
modifying criteria is basically the result of the
public comment period.
8
9
And then to just briefly review those
remedial alternatives that basically survived the
10
11
process of elimination.
This lists the
12
alter~~tives that we are required by law to carry
through the whole evaluation process, the no
13
14
15
action alternatives.
That gives us a baseline to
evaluate the other alternatives from it.
16
Basically, what a no action alternative is you
17
don't do anything with the site.
Then let me
18
19
point out why there -- the "P" stands for the
plant and the "L" stands for the lagoon area.
20
21
The second alternative we are looking at
long-term monitoring as well as fencing portions
22
23
of the northeast tributary where we had elevated
levels of contaminants in the surface water and
24
25
sediment.
The third alternative would be long-term
-------
1
2
monitoring, implementing institutional controls,
and then, again, fencing that portion of t~e
3
northeast tributary where elevated levels of
4
5
contaminants were detected, that were already
outside the fenced area.
That's already -- the
6
fence is already in existence.
.7
Alternative number 4, 4-A, -- okay; all the
8
9
fours are basically the same.
It's extracting
groundwater through extraction wells, and the only
10
11
difference between A and B is the type of
treatment for the extracted groundwater.
12
13
TTnder A the water will be treated through a
air stripper.
I have some pictures of that just
14
15
to help you picture what an air stripper is, and
then the contaminated exhaust coming off the air
16
stripper would be treated through a vapor
incinerator with the treated groundwater being
17
18
discharged through the local sewer system.
19
Then under alternative B, again, we're using
20
21
air stripping as our primary treatment.
Excuse me
-- A is -- alternative 4-A deals with air
22
23
stripping and using carbon absorption which means
the off gas coming from the air stripper to remove
24
25
the contaminants out of that air stream prior to
being discha~ged to the environment, with the
-------
- ..
1
2
groundwater discharging -- with the treated
groundwater being discharged to the local sewer
3
system.
Then alternative 4-B uses the fume
4
incinerator and the activated carbon to treat the
5
exhaust gas coming from the air stripper.
6
As far as the surface water, the first
7
alternative is no action, the second one is long-
8
9
term monitoring.
Basically, it's our opinion that
by treating the groundwater we will be addressing
10
11
the contaminants that are migrating into the
surface stream along with the contaminated
12
13
groun~water, so when we stop the migration of the
contaminated groundwater at that stream, we will
14
remediate the stream as well.
15
16
The next page lists what EPA has identified
as our preferred alternatives.
Basically it's
17
long-term monitoring along with institutional
controls along with groundwater extraction using
18
19
air stripping as the primary treatment, using fume
incinerators to treat the off gas coming off the
20
21
air stripper and then discharging all the treated
groundwater to the local sewer system along with
22
23
the rest of the discharge at the existing site
that goes to the Salisbury treatment plant and
24
25
then as far as the surface water, just long-term
-------
~~
1
2
monitoring, continue to sample, to provide the
data necessary to assure that the stream is being
3
4
remediated by the groundwater remediation system.
Then the last page basically lists
5
conversations between us and the State.
We were
6
uncomfortable with the evaluation that was done
7
for the soils part of the site, so we have -- we
8
9
are going to request that the National Starch and
their contractors revisit that, which will result
10
in a fourth operable unit, which will mean another
11
12
public meeting, which will just discuss the soil
remed~ation aspect of the site, and hopefully that
13
14
will occur within about four months, estimated
time frame.
15
Just for some pictures of what an air
16
stripper is, (displaying photographs) these
17
.
pictures were taken at another Superfund site
18
19
called Chemtronics.
It is in Swannanoa, North
Carolina.
Basically, this is a picture of the
20
computer system that runs the whole groundwate~
21
extraction system.
22
23
This basically is the extraction well,
Okay.
drilled down to the bedrock.
It has pressure
24
sensors in it.
It has meters to measure the flow
25
and this is ~ll fed back into the computer system
-------
.) ..
1
2
so that the computer can turn the pump on and off
as necessary.
3
Okay.
This is the house -- this is the
4
building that was built on site to house the
5
treatment system.
The blue stack sticking out is
6
the air stripper.
7
Okay.
The first apparatus that the
8
9
groundwater discharges into once it gets pumped
out of the ground is called an equalization tank
10
11
and this is a picture of one.
Basically, it
allows basically the purpose of it is to have the
12
main ~istem see a constant flow of -- of water
13
flowing through it.
Okay.
This is the base of
14
the air stripper.
Air is blown into the bottom
15
16 .
and the water is pumped to the top and allowed to
trickle down as the air is flowing up forcing the
17
18
volatile organics out with the water.
Okay Following the air stripper is the water,
19
20
groundwater, is pumped through these canisters
which contain activated carbon.
Basically, it
21
22
polishes the water to ensure that all the
contaminants have been removed, and then from this
23
24
point it's discharged into the Buncombe County
sewer system.
There's one more.
Bere we go.
And
25
then this is ~ picture of what a fume incinerator
-------
.,).::
1
2
looks like. . That's all I have for pictures of
these.
3
4
Basically that's the end of my presentation.
Because we have a court reporter and because this
5
is for the record, if you have any comments or
questions, please state your name and you need
6
7
anything else?
8
9
(WHEREUPON, the reporter indicated
negatively. )
10
MR. BORNHOLM:
Please state your name before
11
you make your comment or ask your question.
I'll
12
open ~t up to you.
Do you have any questions or
13
14
comments?
MS. BARRETT:
Jon must have really informed
15
you mighty well, to not have any questions.
16
17
What's wrong with
MR. YOUNG:
I'm Wes Young.
the soil that you have to go back to the operation
18
19
MR. BORNHOLM:
It's not what's wrong.
The
20
alternatives that were looked at and the
21
feasibility studies, in our opinion, did not qo
far enough and we want them to do a further
22
23
evaluation of the remedial alternatives that may
be available to address the soil contamination a;
24
25
the site.
I~'s our opinio~ that sufficient data
-------
, ,
1
2
already exists but basically ours will be a really
an effort of more evaluation of the technologies
3
4
available.
MR. YOUNG:
Where's the soil now?
5
6
MR. BORNHOLM:
The soil is -- this shows both
areas (indicating on document).
This is the
;
8
figure that delineates the distribution of acetone
in the soils.
There's a hot spot of contamination
9
in this area which is near the lagoon area and
10
basically in this area at the facility.
This area
11
12
that's shaded here is the plant itself which is on
a con-rete foundation and then the area between
13
14
here, over here, and over here is all paved,
driveways.
Basically, the contaminated soil is
15
16
down under the facility itself.
And then as far as this area is concerned,
17
18
the levels of contaminants in the groundwater are
higher than the levels in the soil which basically
indicates that through natural -- the process of
19
20
natural percolation of rain, snow through the
soil, it's carrying that contaminant to the
21
22
groundwater and it's our feeling that with the
23
groundwater pump and treat system will catch that
24
25
contamination as it migrates into the groundwater,
at least for .this area in here.
That's the
-------
-..
1
2
initial idea.
Any other questions or comments?
MR. BEAR:
Does any of the contamination
3
left the soil yet?
Left the property?
4
MR. BORNHOLM:
To the best of our knowledge,
5
6
no.
Could you state your name please for the
record?
7
MR. BEAR:
Odell Bear.
8
9
MR. BORNHOLM:
To the best of our knowledge,
no.
Based on all the information from operable
10
units one, two and the work done as far as
11
12
operable unit three, no contamination has left the
site..
13
14
Something was in the paper about
MR. BEAR:
it traveling north; is that true?
15
Its tending to follow the
MR. WINSTON:
16
17
It's tending to follow the stream in a
stream.
northerly direction.
18
19
Which flows in a northerly
MR. BORNHOLM:
direction.
20
21
It hasn't gotten off the site,
MR. WINSTON:
off the property.
MR. BORN HOLM :
(Indicating on document) This
22
23
is the figure for groundwater and saprolite area
and there is a well down here with a concentration
24
25
of one -- I ~hink it's one parts per billion,
-------
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
which is right at our detection levels, that we
can't detect below that, per se. And then the
paired well with that, which is in bedrock has the
same concentration. Again, that's right at the
quantitation limits of our current technology for
detecting contaminants, so one day that could be
zero and one day that could be one, depending on
the how finicky the machines are. So
basically, what that's showing us is that the
contaminants have not left the site via
groundwater, through the groundwater.
MS. BARRETT: Are there any more questions
before we conclude our meeting? Okay. Well, we
thank you very much for your attention and for
coming and the meeting is adjourned.
MR. BORNHOLM: Thank you.
(WHEREUPON, the meeting was concluded at 8:00
P. M.)
********
-------
(STATE OF NORTH CAROLINA )
COUNTY OF MECKLENBURG )
CERTIFICATE
I, Shannon S. McGilberry, Certified Verbatim
Reporter and Notary Public, do hereby certify that foregoing
public meeting in the referenced matter was taken by me and
transcribed under my supervision and that the foregoing
thirty-six (36) pages constitute a verbatim transcription of
same.
I do further certify that I am not of counsel
for or in the employment of any of the parties to this
action/ nor do L have any interest in the result thereof.
IN WITNESS WHEREOF, I have hereunto
subscribed my name, this 16th day of August, 1993.
Shannon S . McGilberry 0
Certified Verbatim Reporter
Notary Public
My Commission Expires:
August 16, 1993
PLEASE NOTE that unless otherwise specifically requested in
writing, the tape for this transcript will be retained for
thirty days from the date of this certificate.
------- |