PB94-964053
EPA/ROD/R04-94/182
September 1994
EPA Superfund
Record of Decision:
ABC One-Hour Cleaners Site,
Operable Unit 2, Jacksonville, NC,
9/6/1994
-------
RECORD OF DECISION.
ABC ONE-HOUR CLEANERS SITE
JACKSONVILLE, NORTH CAROLINA
OPERABLE UNIT 2
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION IV
ATLANTA, GEORGIA
-------
RECORD OF- DECISION
ABC ONE-HOUR CLEANERS SITE
OPERABLE UNIT 2
TABLE OF CONTENTS
Descrfptlon
Page
DBC~TION FOR TH~ R~CORD OF DBCISION
. . . . . . .
. . . .
1.0
DECISION SUMMARY
. . . .
2.0
3.0
4.0
5.0
6.0
7.0
. 0 0 0 0 0
. 0 0 . . . . . .
. . .
S:ITE
1.1
1.2
1.3
1.4
1.5
1.6
NAHB, LOCATION, AND DESCRIPTION. . . . . . . . . .
Site Location. . . . . . . . . . . . . . . . . . .
Surface Features. . . . . . . . . . . . . . . . .
Soi 1 s . . . . . . . . . . . . . . . . . . . . . . .
Hydrogeology. . . . . . . . . . . . . . . . . . .
Groundwater Flow Direction. . . . . . . . . . . .
Demography and Land Use. . . . . . . . . . . . . .
SITE HISTORY AND ENFORCEMENT ACTIVITIES
2.1 Facility Operations and History .
2.2 Enforcement Activities. . . . .
. . . .
. . . .
. . .
. . .
. . .
. . .
. . . . . .
COMMUNITY PARTICIPATION HIGHLIGHTS. .
. . . . .
. . . .
SCOPE AND ROLB OF RESPONSE ACTION
. . . .
. . . .
. . .
SUMMARY OF SITB CHARACTERISTICS. . . . . . . . . . . .'
5.1 Nature and Extent .of Contamination. . . . . . . .
. 5.1.1. Septic Tank. . . . . . . . . . . . . . . .
5.1.2 Soils. . . . . . . . . . . . . . . . . . .
5.2 Contaminant Fate and Transport. . . . . . .
SUMMARY OF SITE RISKS. . 0 . 0 . . . . . . . . . . . .
6.1 Contaminants of Concern. . . . . . . . . . . . . .
6.2 Exposure Assessment. . . . . . . . . . . . . . . .
6.3 Toxicity Assessment. . . . . . . . . . . . . . . .
6.3.1 Carcinogens. . . . . . . . . . . . . .
6.3.2 Noncarcinogens . . . . . . . . . . . . . . .
6.4 Risk Characterization. . . . . . . . . . . .
6.4.1 Carcinogenic Risks. . . . . . . . . . . . .
6.4.2 Noncarcinogenic Risks. . . . . . . . . . . .
6.5 Ecological Considerations. . . . . . . . . .
6.6 Risk Uncertainty. . . . . . . . . . . . . .
6.7 Remedial Action Objectives (RAO) . . . . . . .
DESCRIPTION OP REOOEDIAL ALTERNATIVES. . . . . . . . . .
7.1 Alternative 1: No Action. . . . . . . . . . . . .
7.2 Alternative 2: Institutional Controls. . . . . .
i
1
1
1
1
1
2
3
3
3
3
6
6
7
7
7
8
9
9
10
10
11
11
12
12
12
13
13
14
15
15
16
17
17
-------
1-'1 (-'/~.f)[-'). t)f: OrC'C'IO' N
"\L_'~'\../" . \.. .JC k)
ABC ONE-HOUR CLEANERS SnE
OPEI
-------
RECORD OF DECISION
ABC ONE-HOUR CLEANERS SITE
OPERABLE UNIT 2
TABLE OF CONTENTS
Description
Page
APPENDIX
Figure 1
Figure 2
A - LIST OF FIGURES
Site Location Map.
. . . .
. . 1
. . . . . . . .
Base Map for Cross Section A-A' and B-B'
. . . . . . 2
Figure 3A Cross Section A-A'
. . . . .
. . . . 3
. . . . .
Figure 3B Cross Section B-B'
Figure 4
Figure 5
. . . . .
. . 4
. . . . . .
. . . .
Locations of Temporary Monitoring wells Installed
by NRCD in 1985 . . . . . . . . . . . . . . . . .
. . 5
Soil Boring Locations.
. . . .
. . 6
. . .' . . . . . .
Table 1
APPENDIX B.- LIST OF TABLES
Table 2
Results of Analyses of Septic Tank Samples For
Volatile Organic Compounds ABC One-Hour Cleaners
Operable Units 1 and 2 .. . . . . . . . . . . .
. T-1
Soil Sample Analysis Results Summary ABC One-Hour
Cleaners Operable Unit 1 (June 1991) and Operable
Unit 2 (September 1993) . . . . . . . . . .
. T-2
Table 3 Contaminants of concern. . . . . . T-8
Table 4A .Exposure point concentrations for current on-site
worker . . . . . . . . . . . . T-9
Table 4B Exposure point concentrations for future resident T-10
Table 4C
Exposure point concentrations for future
construction worker. . . . . . . .
. . . .
T-11
Table 5A Model for calculating doses from incidental
ingestion of soils . . . . T-12
Table 5B Model for calculating doses from dermal contact
with soil . . . . . . . . T-13
-------
r~ECORD OF DECISION
ABC ONE-HOUR CLEANERS SITE
OPERABLE UNIT 2
TABLE OF CONTENTS
Description
Page
Table 6
Table 7
Table 8
Table 9
EPA Weight-of Evidence Classification System for
carcinogenicity. ....
Carcinogenic Chemicals of concern and their EPA
and IARC classification.
Health criteria contaminants of concern in soil.
Remedial Action objectives for contaminants of
concern.
APPENDIX C - RESPONSIVENESS SUMMARY
APPENDIX D - STATE CONCURRENCE
T-15
T-16
T-17
T-18
-------
DECLARATION FOR THE RECORD OF DECISION
OPERABLE UNIT #2: SOIL
Site Name and Location
ABC One-Hour Cleaners Site ..
. Jacksonville, Onslow County, North Carolina
Statement of Basis and PUl'DOse
This decision document presents the selected remedial action for Operable
Unit 2 (soil) for the ABC One-Hour Cleaners Site in Jacksonville, North Carolina,
which was chosen in accordance with the Comprehensive Environmental
Response, Compensation, and Uability Act of 1980 (CERCLA), as amended by
the Superfund Amendments and Reauthorization Act of 1986 (SARA), and to
the extent practicable, the National Oil and Hazardous Substances Pollution
Contingency' Plan (NCP). This decision is based on the Administrative Record
for this site.
The State of North Carolina concurs with.the selected remedy.
Assessment of the Site
Actual or threatened releases of hazardous substances from the Site, if not
addressed by implementing the response action selected in this Record of
Decision (ROD), may present an imminent and substantial endangerment to
pUblic health, welfare, or the environment.
Descrl tlon of the Selected Rem
This operable unit (OU) is the final action of two OUs for the site. The OU-1
involves remediation of the groundwater. This OU-2 addresses the principal
threat remaining at the site by treating the contaminated soils.
The selected remedy includes:
Remediation of contaminated soils using Soil Vapor Extraction (SVE).
Implementation of Institutional Controls
i
-------
Statutory Determinations
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 (or resource
recovery) technology to the maximum extent practicable, and satisfies the
statutory preference for remedies that employ treatment that reduce the
toxicity, mobility, and/or volume as a principal element.
Because this remedy may result in hazardous substances remaining on-site, a
review will be conducted within five years after commencement of remedial
action to ensure that the remedy continues to provide adequate protection to
human health and the environment.
~.(YJ~r
John H. Hankinson Jr.
Regional Administrator
„~ G.)/9Cf4
Date
-------
ROD-OU2
ABC Site
Page 1
RECORD OF DECISION
DECISION SUMMARY
1.0 SITE NAME. LOCATION. AND DESCRIPTION
1.1 Site Location
'ABC One-Hour Cleaners Site (also referred to as the ABC Site or the Site) is .
located at 2127 Lejeune Boulevard, Onslow County, Jacksonville, North
. Carolina (Figure 1). Jacksonville, NC is located on the coast about forty-five
miles north of Wilmington, NC. The dry cleaning facility encompasses an area
of approximately 1 acre. ABC One-Hour Cleaners consists of three buildings
joined to form one complex and Is located on the south em portion of the
property. A small parking lot fronts Lejeune Boulevard with driveways on the
east and west of the complex. The northem most one-third of the Site is a
. grassy field. Across Lejeune Boulevard to the south are woodlands and the
Tarawa Terrace Housing Development. The Tarawa Terrace complex serves as
housing for non-commissioned officers of the Camp Lejeune Marine Corps
Base (Base), and their families..
. 1.2 Surface Features
The ABC Site Is situated at an elevation of about 30 fe,et above mean sea level
(msl). The facility is located approximately 4,000 feet northwest of Northeast
Creek, which Is situated at an elevation of approximately 5 feet above msl
and. is influenced by tidal changes. Elevations decline gradually to the south
and southeast, toward Northeast Creek. This creek flows southwestwardly
towards the New River, which drains into the Atlantic Ocean.
Surface runoff from the ABC Site flows overland into ditches and culverts that
are directed across Highway 24 onto Base property and, along with runoff
originating on the Base, Into Northeast Creek.
1.3 Soils
The soils in the site area have been classified in the Baymeade-Urban land
complex series (USDA, 1992). Fifty percent of this soil type is well drained
Baymeade; 30% is covered by building, streets, etc.; the rest includes soil that
has been disturbed during urban development. Surface layers are dominated
by gray fine sand. Subsurface layers from 0 to 2 inches below ground surface.
(bgs) are dominated by gray fine sand. Subsurface layers from 2 to 30 Inches
-------
ROD-QU2
ABC Site
Page 2
bgs are composed of fine sand that is light gray, light yellow brown, and white
in color. Subsoils (from 30 to 80 inches bgs) are dominated by brownish yellow,
yellowish brown fine sandy loam.
From soil samples collected as part of the OU2 RI, the shallow soils (from
ground surface to approximately 25 feet bgs) consist of finely interbedded
sand, silts, and clays. Clay is the major component within the first 12 feet of
the soil profile. Sand in this zone is quartz rich and very fine to fine grained.
Increasing with depth, the percentage of sand becomes higher and more
coarsely grained.
1.4 Hydrogeology
Data on the geology underlying the ABC site were generated from soil borings
and the piezometer and monitor well installations. Figure 2 shows the location
of cross-sectional views of the site, and Figures 3A and 3B show the cross-
sections of the site. Geologic data from the soil borings extend to the
maximum depth of the upper unsaturated soils (typically encountered at
approximately 18 feet bgs). Data generated during OU2 sampling extend to a
depth of 175 feet bgs. OU1 information was provided from the C-4 boring to a
maximum depth of 200 feet bgs. Geologic data generated from split-spoon
samples extend to a depth of approximately 30 feet bgs. Additional data was
based on examination of mud rotary drill cuttings.
During OU 1, five distinct lithologic layers were found underlying the ABC study
area. OU2 data, from advancement of monitor well borings, confirm that five
different layers are found underlying the study area (Figures 3A and 38). The
first (uppermost) zone encountered extends from ground surface to
approximately 25 feet bgs. The unconsolidated sediments comprising this zone
are typically inter-bedded sands, silts, and clays. The percentage of clay is
highest within the first 12 feet bgs. Quartz-rich sand is very fine to fine grained
until approximately 20 feet bgs where coarse grained sand becomes
prevalent.
The second zone extends on average from approximately 25 feet bgs to 65
feet bgs. The unit is described as a saturated sand with variable amounts of
clay , silt, or gravel (silt and gravel content estimated at less than 15% by
volume). At two piezometer locations (PZ-01 and 02, and PZ-05 and 06), the
bottom 10 feet of this zone were predominantly composed of fine grained
sand. The third layer is a silty, clayey sand that was obseNed underlying the
clean sands. Where observed, this layer was typically about 10 feet thick and
first observed at about 60 feet bgs, with the exception of C 10 where the layer
-------
ROD-OU2
ABC SIte
Page 3
was about 15 feet thick and first encountered at about 52 feet bgs. This silty
clayey, fine quartz sand is composed of approximately 15% silt, 40% clay, and
45% .sand and is made up of very fine grained quartz grains. .
. .
. . . .
. . . .. . . .
. .
The fourth layer encountered, thought to represent the Castle Hayne
Formation, was typically encountered at 70 feet bgs, although at well C10 it
was first observed at approximately. 85 feet bgs. The formation contains fossils
Including shark teeth, sea urchin spines, and/or various other small shells and
shell fragments. The matrix is predominately composed of calcareous sands to
quartz sands.
The fifth layer is found within the Castle Hayne. During OU 1 and OU2, a highly
cemented layer of fossiliferous sands was encountered at about 90 feet bgs.
Below this layer, the fossiliferous sands and gravels became increasingly silty.
This siltier material comprises an almost distinct layer. Wrth depth, the layer
appears. to consist of approximately equal volumes of silt and sand.
1.5 Groundwater Flow Direction
Groundwater levels were measured in surficial aquifer monitoring wells and
Castle Hayne aquifer monitoring wells during au 1 and OU2. In the surficial
aquifer the groundwater flow appears to be generally from the northwest to
the southeast toward Northeast Creek; and in the Castle Hayne aquifer to the
east south-east with a stronger eastem component than was estimated for the
Surficial aquifer. Additional information could be found in the OU 1 and OU2
remedial investigation reports.
1.6 Demography and Land Use
The ABC Site is located in the Jacksonville city limits. The population within a
1-mlle radius of the Site is approximately 2,800 and includes approximately 726
houses. Properties in the area to the east and west of the ABC Site are
presently used for general retail and commercial business purposes. To the
north of the Site are residential areas, including Pinewood Downs, a multi-family
residential development.. Land located to the south serves as housing for
noncommissioned officers and also contains woodlands.
2.0 SITE HISTORY AND ENFORCEMENT ACTIVITIES
2.1 Facility Operations and History
ABC One-Hour Cleaners, Inc., is a North Carolina corporation registered with
-------
ROD-0U2
ABC SIte
Page 4
the Secretary of State as of March 4, 1958. Martha Melts and Milton Melts
purchased the property on which the ABC One-Hour Cleaners facility is
located on September 16, 1964. Prior to purchasing, the Melts' leased the
property from Carolina Eastem Realty Company, Inc. (lease entered into on
May 2, 1955). According to the lease document, the building was previously
used as a mOdel/hobby shop. Currently, Mr. Melts serves as the President of
ABC One-Hour Cleaners; Victor Melts is the Vice President, Secretary, and
Treasurer. Victor Melts and Milton Melts are the sole directors and shareholders
of ABC One-Hour Cleaners.
Typical of the dry cleaning industry, ABC One-Hour Cleaners utilizes
tetrachloroethene (PCE) as a dry cleaning solvent. The solvent was stored in a
250-gallon above-ground storage tank located along the west side of the
building. Used PCE was reclaimed through a filtration-distillation process
contained within the main building. Following completion of the distillation
process. the still bottoms, consisting of powder residues, were placed in the
driveways around the building as a "pothole" filler. It is estimated that
approximately 1 ton of still bottoms was placed on the driveways over a 30-
year operating period. Since 1985, ABC One-Hour Cleaners has used the
services of Safety-Kleen, Inc. to recover and recycle its dry cleaning fluid.
According to the Resource Conservation and Recovery Act (RCRA), still
bottoms are considered to be a hazardous waste (RCRA Waste No F002). ABC
One-Hour Cleaners is classified as a small quantity generator under RCRA
(No.NCD981751126), and generates less than 1,000 kilograms per month of
hazardous waste.
A septic tank soil absorption system is located in the rear of the building
complex. The septic system consists of an underground concrete tank with a
concrete lid and a pipe of unknown length that discharges into the subsurface
soil. The septic system is located within 4 feet of the PCE storage tank. The
age of the septic system reportedly dates back to the original construction of
the building (1940's). ABC One-Hour Cleaners began occupying the building
in 1955. In the 1960's, ABC One-Hour Cleaners installed a floor drain to the
septic tank and tied its wastewater discharge, except for its lavatories, into the
Weyerhaeuser Properties' water and sewer system. The lavatories remained
tied into the septic system until approximately 1985, at which time they were
also tied into the Weyerhaeuser Properties' system.
In July 1984, as part of a routine water quality evaluation, the Department of
the Navy collected groundwater samples from 40 of the 100 community water
supply wells located on the Base. The Navy determined that dichloroethene
-------
ROp-oU2
ABC Site
Page 5
(DCE), trichloroethene (TCE), and PCE were present in 10 of the wells sampled.
Of the 10 wells in which groundwater contamination was noted, 8 of the wells.
had been directly impacted by sources located on the Base. The remaining
two wells were located within the Tarawa Terrace well field (TT-23 and .1T-26; .
see Figure 4) in the vicinity of two off-base commercial dry cleaning
operations, ABC One-Hour Cleaners, Inc., and Glam-O-Rama, Inc.
In February 1935, the two affected wells plus a third community well (TT-25)
were disconnected from the Base's drinking water supply system. In June 1985,
an emergency water line from the Base's Holcomb Boulevard system was
installed to provide the Tarawa Terrace development with drinking water.
During the same time period, the Wilmington Regional Office (WiRO) of the
Division of Environmental Management, North Carolina Department of Natural
Resources and Community Development (NCDNRCD), now called North
Carolinq Department of Environment, Health and Natural Resources.
(NCDEHNR), was notified by the United States Marine Corps, that two deep
water wells in the Tarawa Terrace housing area at the Base were
contaminated by what appeared to be off-site sources. From April through
September 1985, WiRO staff conducted a groundwater pollution study to
define the source of PCE in wells within the Tarawa Terrace well field. The
study concluded that the most likely source of groundwater contamination
was determined to be ABC One-Hour Cleaners, Inc.
On January 24, 1986, WiRO notified Mr. Milton Melts, president of ABC One-
Hour Cleaners, Inc., that he was in violation of the following North Carolina
General Statutes:
1)
G.S. 143-215.1(a)(5) for changing the nature of waste discharged
through a disposal system by disposing of dry cleaning solvents In
the septic tank system.
G.S. 143-215.1 (a)(6) for discharging dry cleaning solvents in the
septic tank nitrification field resulting in the violation of standards
for underground waters.
2)
Subsequent to the receipt of the Notice of Violation issued by NCDNRCD, ABC
One-Hour Cleaners contracted the services of Law Engineering and Testing,
Inc., to conduct preliminary investigations of the septic tank soil absorption
system and surrounding soils. The results of two preliminary investigations
conducted on April 8, 1986 and September 10-11, 1986, confirmed the
-------
ROD-OU2
ABC Site
Page 6
. ----.----- -------~-_._--------
presence of PCE and its derivatives in soils immediately surrounding the septic
tank and adjacent to an existing floor drain. Thus, ABC One-Hour Cleaners
was confirmed as the source of groundwater contamination.
On October 30, 1986, ABC One-Hour Cleaners subm;tted a proposal for a
remedial action plan involving partial removal and/or treatment of
contaminated soils. The plan, according to NCDNRCD, failed to address
problems associated with the groundwater contaminant plume emanating
from beneath the ABC One-Hour Cleaners facility. The NCDNRCD rejected the
proposed plan and proceeded with application of the Hazard Ranking System
(HRS) and nomination of the Site for inclu$ion on the Superfund National
Priorities List (NPl) of uncontrolled hazardous waste sites.
2.2 Enforcement Activities
Based upon observed releases of PCE and existing groundwater
contamination, as well as other factors considered in the application of the
HRS, the ABC One-Hour Cleaners Site was scored at 29.11. Sites with scores of
28.5 or greater are listed on the NPL. Accordingly, the Site was proposed for
NPL listing in June 1988, and placed on the fir 101 1i<;1 in fv1Clrch 1989.
On September 29, 1988, EPA sent a special notice leHer to the current
landowner and president of ABC One-Hour Cleaners Inc., Milton Melts,
notifying him of his potential responsibility for the release of hazardous
substances at the ABC One-Hour Cleaners Site in Jacksonville. North Carolina
and requesting him to conduct a Remedial Investigation and r easibility Study
(RI/FS) for the Site.
Since the PRPs were unable to conduct the RifFS, EP/\ hired Roy F. Weston, Inc.
fa conduct the RifFS. In June 1992 the Site was divided into nvo OUs: OU-1:
Groundwater and OU2: Soils. The Record of Decision ([
-------
ROD-OU2
ABC Site
Page 7
public in both the Administrative Record located in an information repository
maintained at the EPA Region IV Docket Room and at the Onslow County
Public Library in Jacksonville North Carolina. In addition, the Proposed Plan fact
,sheet was maileq to ~h~,i~~ivlqualsQtthe. Site,rn.ailing ,list on MayJ.l; ~994.;~ .
The notice of the availability of these documents and notification of the
Proposed Plan Public Meeting was announced in The Wilmington Moming Star
on May 16, 1994. A public comment period was held from May 16, 1994
through June 15, 1994. In Addition a public meeting was held on May 24, 1994
at the Onslow County Public Ubrary. At this meeting, representatives from EPA
answered questions about problems at the Site and the remedial altematives
under consideration. A response to the comments received during the
comment period, Including those raised during the public meeting, are
addressed in the Responsiveness Summary, which is part of this Record of
Decision. The Responsiveness Summary also incorporates a transcript of the
Proposed Plan public meeting.
4.0 SCOPE AND ROLE OF RESPONSE ACnON
The response action at this Site was divided Into two units or phases, referred
to as operable units. The operable units (OUs) at this Site are:
. OU 1 - Groundwater Contamination
. OU2 - Soil Contamination
EPAselected the remedy for OU-1 in a ROD signed on January 28,1993. This
action is in the remedial design stage.
OU-2, the subject of this ROD, addresses the soil contamination at the Site. The
intent of this response action is to remove the principal threat remaining at the
Site by treating the contaminated soils. Treating the soil will also prevent the
contaminants from adversely impacting the groundwater.
This is the last ROD contemplated for this Site.
5.0 SUMMARY OF SITE CHARACTERlsnCS
5.1 Nature and Extent 01 Contamination
During the OU2 field investigation program, three media were investigated,
(septic tank sludge, soil and groundwater). This ROD addresses soil
-------
ROD-0U2
ABC SIte
Page 8
contamination (actual source), therefore groundwater results are not
discussed. Groundwater data were collected during the aU2 field activities to
define some au 1 data gaps that will help in the design of the already
selected remedy for groundwater.
As determined from previous investigations and confirmed through this aU2
investigation, the presence of VOCs in unsaturated soils underlying and
surrounding ABC supports the conclusion that the septic tank serves os the
principal source for contamination to both groundwater and soils of the area.
The secondary source of contamination involved the historical practice of
placing still bottoms, consisting of powder residues, around the ABC building as
a "pothole" filler.
The source investigation was divided in two parts; septic tank and soils. Septic
tank efforts involved collecting a grab sample of the septic tank sludge. Soil
sampling efforts focused on surficial and subsurface soils directly beneath and
immediately adjacent to the ABC facility. This section summarizes the results of
the source investigation.
5.1.1. Septic Tank
A sample of the sludge and liquid contents of the septic tank within the ABC
building was collected to obtain information relative to the concentration of
VOCs contained in the septic tank.
Analytical results of septic samples are presented in Table 1. The results
indicated PCE concentrations in excess of an estimated 240,000,000 Jlg/kg of
PCE. However, the result was qualified with a footnote CU") indicating that the
compound was analyzed for but not detected. Complications arose when
trying to quantify the concentrated sample and although the septic tank
sample and an accompanying laboratory blank were analyzed by the CLP
laboratory, the concentrations were such that the sample required dilution.
Upon dilution and re-analysis, the results indicated concentrations of 10 times
le~ than that of the laboratory blank (non-detectable according to
established CLP protocols). Based upon these results, a review of the initial
analysis of the sample was performed and PCE concentrations in the range of
240,000,000 Jlg/kg were estimated.'
Analytical results for all other TCL-VOC parameters could not be determined;
but are reported as 160,000,000 Jlg/kg with a "U" data qualifier.
These results further suggest that the septic tank system represents a historical
source for chlorinated VOCs observed for both area soils and groundwater.
-------
ROD-oU2
ABC Site
Page 9
During OU2 field activities the liquids and sludge inside the septic tank were
removed, eliminating one of the historical sources of contamination.
5.1.2$0111
Nineteen (19) soil borings were completed on the interior and exterior of the
ABC facility in order to collect surface and subsurface soil samples. A total of
55 soil samples were collected from these borings. Figure 5 presents the
locations for soil borings and Table 2 presents the VOC analysis data results.
Of the VOCs analyzed for, six compounds generally associated with the dry
cleaning industry were detected above the laboratory analytical detection
limit: PCE; TCE; l,2~dichloroethene (total) (l,2-DCE); and vinyl chloride.
Chloroform and l,l-dichloroethene (1, 1-DCE) were also detected. In general,
three compounds (PCE, TCE, and l,2-DCE) were detected at consistently
higher c.oncentrations, both interior and exterior to the ABC building. . Vinyl
chloride, chloroform, and l,l-DCE were detected in a lesser number of
samples. .
Samples collect~d from soil borings installed in the interior of the ABC building
indicate that PCE, TCE, and l,2-DCE are primary contaminants in the .
unsaturated soil profile (from 0 to 15 feet bgs). Typically, the highest levels of
VOC contamination were detected in the 0- to 2-foot interval beneath the
floor of the ABC building. The soli samples collected from beneath the building
at depths greater than 2 feet bls also contained VOC concentrations above
those detected from samples at similar Intervals outside the building perimeter.
Exterior to the ABC building, VOC concentrations in soil are much lower than
concentrations in soil from beneath the building (except for the samples
collected from a soli boring located in the east driveway, SB-18, Figure 5).
VOC contamination extends from the 0- to 15-foot bgs interval in areas outside
the building. .
Free product was not detected in any of the soil sampling locations.
5.2 Contaminant Fate and Transport
VOCs detected at the site are attributed to releases from ABC. PCE, TCE, 1,2-
:ICE, vinyl chloride, and chloroform are highly volatile, highly mobile, denser
than water and have low to moderate sOil/water partition coefficients. While.
PCE was the only chemical reportedly used at ABC, TCE, l,2-DCE, and vinyl
chloride are present on the site apparently as a result of progressive
-------
ROD-OU2
ABC SIte
Page 10
-------,----~.- --_.' -"-' '----'-'-..."---".-
__L_.",..-. --- ._-- ~
dehaiogenation of PCE and/or as minor constituents of the commercial grade
of PCE used.
Soil concentratIons of VOC contar(dnation are primarily highest within the 0- to
2-feet intervai beneath the ABC building. The higher concentrations of
contaminants in this inteNal are dUt~ to the proximity to sources such as the
septic tank ond potenti01 direct spills to soil and the lack of rainwater infiltration
10 flush the contaminants
Exterior to 1he ABC building, VOC contamination is attributable to historical still
bottoms disposal practices, potential direct spills to soil, and migration of
contaminants from underneath the ABC building. Where asphalt driveways
surrounding the ABC facility exist and are not cracked or broken in some
manner, the contamination has not been subjected to ftushing by rainwater
infiltration. For example, soil samples from the SB-18 soil boring (Figure 5)
located beside the Major Furniture' building and within the asphalt driveway
contained trle highest VOC contaminant levels. Other factors affecting fate
and tran~'. :yt include biologicol. cfiemical, and physical degradation
processes.
6.0 SUMMARY OF SITE RI~K~
A Baseline Risk Assessment (Br~A) for Operable Unit 2 was conducted and the
results are presented in Section 7 of the RI report. The BRA provides the basis
for taking action and indicates the exposure pathways that need to be
addressed by the remedial action. It seNes as the baseline indicating the risks
that could exist if no action is taken at the Site. This section of the ROD
summarizes the results of the BRA conducted for this Site.
6.1 Contaminants of Concern
Soil data collected during the RI were reviewed and evaluated to determine
the contaminants of concern at the Site which are most likely to pose risks to
the public health. The selected contaminants of concern for the Site soils are
shown on Table 3.
Once these contaminants of concern were identified, exposure concentrations
were estimated. Exposure point concentrations were calculated for each of
tl)e contaminants detected in the soil based on the potential current and
future receptors and their respective assumptions (Le., current on-site worker,
future resident, and future construction worker). The exposure point
concentrations were calculated using the lesser of the 95 percent upper
-------
ROD..QU2
ABC Site
Page 11 .
confidence limit on the arithmetic concentration mean or the maximum
detected value as the reasonable maximum exposure (RME) point
concentration. Tables 4 show the exposure point concentration for the
different scenarios. . . . . . . . .
6.2 Exposure Assessment
The objective of the exposure assessment is to estimate the magnitude of
potential human exposure to the soil contaminants of concem at ABC.
Current and future receptors were evaluated based on current (commercial)
. and potential future (commercial/residential) land use.
Currently, there are workers on site. The exposure pathways for the current
worker scenario group include dermal contact with and incidental ingestion of
contaminants in surface soils (0 - 1') surrounding the ABC building.
. Future potential receptors include an on-site construction worker and the
possible receptors of a future residential scenario.
The Mure on-site construction worker potential exposure pathways include
dermal contact with and incidental ingestion of contaminants in surface and
subsurface soils. A conservative exposure duration of six months was assumed.
It was assumed that the Site will be available for unrestricted use in the Mure.
Therefore a future residential scenario was evaluated. Exposure to surface soil
(0 - 1') was assumed for a future child (1-6 yrs), youth (7-16 yrs) and adult
resident based on general contact. Dermal exposure and incidental ingestion
were considered as exposure routes of contact to surface soils through a
number of activities. A year-round exposure of 350 days/year was assumed
and its was divided into a 6-year duration for the child, a la-year duration for
the youth and a 14-year duration for adults for a total of 30 years of exposure.
The mathematical models and the assumptions that were used to calculate
the intakes (i.e., doses) of the chemicals of concern for each receptor through
the applicable exposure route are presented in Tables 5A and 58.
6.3 Toxlci Assessment
In evaluating potential health risks, both carcinogenic and non-carcinogenic
effects were considered. The potential for producing carcinogenic effects is
limited to substances that have been shown to be carcinogenic in animals
-------
ROD-OU2
ABC Slta
paga 12
and/ or humans. Excessive exposure to all substances carcinogenic or
noncarcinogenic, can produce non-carcinogenic effects. Therefore, reference
doses when available are identified for every chemical selected regardless of
its classification, and cancer slopes are identified for those chemicals classified
as corcinogenic.
6.3. 1 Carcinogens
Slope factors (SFs) have been developed by EP A for estimating excess lifetime
f~ancer risks associated with exposure to potentially carcinogenic
contaminants of concem. SFs, which are expressed in units of (mg/kg-day} I,
are multiplied by the estimated intake of a potential carcinogen in mg/kg-day
to provide an upper bound estimate of the excess lifetime concer risk
associated with the exposure at the intake level. The term "upper bound"
reflects the conseNative estimate of the risk calculated from the SFs. Use of
these approaches makes underestimation of the actual cancer risk highly
unlikely. SFs are derived from the results of human epidemiological studies of
chronic animal bioassays to which animal-fo-human extrapolation and
uncertainty factors have been applied (e.g., to account for the use of animal
data to predict effects on humans).
The EPA weight-of-evidence classifications system for carcinogenicity is
presented in Table 6 and the carcinogenicity classification for the
contaminants of concem is presented in Table 7.
6.3.2 Noncarcinogens
Reference doses (RIDs) have been developed by EP A for indicating the
potential for adverse health effects from exposure to contaminants of concem
exhibiting noncarcinogenic effects. RfDs, which are expressed in units of
mg/kg-day, are estimates of lifetime daily exposure levels for humans, including
sensitive individuals. Estimated intakes of contaminants of concem from
environmental media (e.g., the amount of a contaminant of concern ingested
from contaminated drinking water) can be compared to the RIDs. RfDs are
derived from human epidemiological studies or animal studies to which
uncertainty factors have been applied (e.g., to account for the use of animal
data to predict effects on humans). The RfDs used in this evaluation and the
reference used for each contaminant are listed in Table 8.
6.4 Risk Characterization
This risk cholOcterization is an evaluation of the nature and degree of potential
-------
ROD-QU2
ABC Site
Page 13
carcinogenic and noncarcinogenic health risks posed to the current worker
and hypothetical future residential and construction workers receptors at the
ABC. site. In this section, human health risks are discussed independently for'
potential carcinogenic- and non-carcinogenic effects for contamin-ants: : .
because of the' different toxicological endpoints, relevant. exposure duration,
and methods employed in characterizing risk.
6~4.1 Carcinogenic Risks
For carcinogens, risks are estimated as the incremental probability of an
individual developing cancer over a lifetime as a result of exposure to the
carcinogen. Excess life-time cancer risk is calculated from the following
equation:
Risk = COI x SF
where:
risk = a unit less probability (e.g., 2x10-5) of an individual developing
cancer;
COI = chronic daily intake averaged over 70 years (mg/kg-day); and
SF = slope factor, expressed as (mg/kg-dayr 1
These risks are probabilities that are generally expressed in scientific notation.
An excess lifetime cancer risk of 1 xl 0-6 indicates that I as a reasonable
maximum estimate, an individual has a 1 in 1 ,OOQ,COQ chance of developing.
cancer as a result of Site-related exposure to a carcinogen over a 7D-year
lifetime under the specific exposure conditions at the Site.
For the current on-site worker scenario, the lifetime excess cancer risk was
estimated to be 2 x 10-5. For the future on-site resident scenario, the lifetime
excess cancer risk was' estimated to be 2 x 10-4, primarily due to ingestion of
and dermal contact with PCE. For the future construction worker scenario, the
lifetime excess cancer risk was estimated to be 6 x 10-7.
6.4.2 Noncarcinogenic Risks
The potential for noncarcinogenic effects is evaluated by comparing an
exposure level over a specific time period (e.g., life-time) with a reference
dose derived for a similar exposure period. The ratio of exposure to toxicity is
-------
ROD-OU2
ABC Site
Page 14
_.,-- ~._->- .---.-.--.
called a hazard quotient CHQ). By adding the HQs for all contaminants of
concern that affect the some target organ (e.g., liver) within a medium or
across all media to whicr, fJ qiven population may reasonably be exposed, the
Hazard Index (HI) can be generated,
The HQ is calculated as to!!O\i'Js:
Non-cancer HQ = CDt/RFD
where:
CDI = Chronic Daiiy InloKe
RfD = Reference dose; and
COI and RfD are ex~>("sed in the same units and represent the same exposure
period (Le., chronic., su, c:hrorlic, or short-term)
The results of the risk calc:uiations ';'idicoted that the hazard index (HI) for the
current worker scenario is bciO\!J iU. the !evel of concern for noncarcinogens.
For future scenarios, hcwC'\!c: the on-site child resident (1-6 yrs.) HI was
estimated to be above 10 ";'.0). rhl=? His for the adult (> 16 years) and youth (7-
16 yrs) on-site residents scencn.:S were estimated to be 0.4 and 0.7,
respectively, primariiy dur' :;-K::idental ingestion of rCE in soil. The future
construction \vor'
-------
I
II
ROD-OU2
ABC Site
Page 15
was spotted In 1987 in Scales Creek, approximately 2-miles southwest of the
Site; Given that the ecological setting of ABC Site is primarily an
urban/residential community, that little suitable wildlife habits have been
identified in the area, and that. the major contaminant pathway of concern
(groundwater migration) does not appear to have impacted any wetland
comml,Jnities, it is doubtful that contamination from this Site would pose a
potential for adverse effects to the ecological environment. Based on these
observations and assumptions, an ecological risk assessment for was not
conducted.
6.6 Risk Uncertainty
There is a generally recognized uncertainty in human risk values developed
from experimental data. This is primarily due to the uncertainty of data
extrapolation in the areas of (1) high to low dose exposure, (2) modeling of
dose response effects observed, (3) route to route extrapolation, and (4)
animal data to human data extrapolation. The Site-specific uncertainty is
mainly due to the degree of accuracy of the exposure assumptions.
In the presence of such uncertainty, the EP A and the risk assessor have the
obligation to make conservative assumptions such that the chance is very
small for the actual health risk to be greater than that determined through the
risk process. On the other hand, the process is not to yield absurdly
conservative risk values that have no basis in reality. That balance was kept 'In
mind in the development of exposure assumptions and pathways and In the
interpretation of data and guidance for the baseline risk assessment for this
Site.
6.7 Remedial Action Objectives (RAO)
Remediation levels for the contaminants of concern in soil were developed to
meet the following objectives:
Prevent direct contact exposure to soil c9ntaining levels of contaminants
that produce unacceptable risks levels. .
Prevent migration of contaminants from soil to groundwater
To calculate the values that prevent migration of contaminants to .
groundwater, two different scenarios were evaluated. The first scenario
considers the present ground surface area exposed to precipitation and
infiltration (structures in place). The second scenario assumes that all the site
-------
ROD-OU2
ABC ~te
Page 16
area will be subjected to infiltration in the future (all structures removed). For
both scenarios, the RAO were calculated using the Summers model equation.
Some of the input parameters for the Summers model equation were
estimated using Site-specific data while others while others were estimated
using data available from scientific literature. The soil-water partition
coefficients (Kds) values were the most difficult input parameter to evaluate.
For PCE, TCE and 1,2 DCE. the Kds were calculated using the Toxicity
Characteristic Leachate Procedure (TCLP). These values mayor may not be
representative of actual Kd values for each contaminant of concern at the
Site because only one leachate test was conducted for Site soils. However,
. given that TCLP is a conseNative approach for determine Kds, the values
derived using this methodology were used rather than literature values. The Kd
for vinyl chloride was estimated using literature values because the test did not
produce contaminant leachate containing vinyl chloride due to insufficient
concentrations in the soils tested.
The Summers Model is an ultra conseNative model for calculating RAO. The
model does not account for contaminant volatilization, retardation, or
biodegradation. Based on the disposal practices at the Site and the
distribution and type of contaminants, these processes are occurring at the
Site. Because these contaminant reducing proce~es are not considered by
the model, the RAOs generated are conseNative.
During remedial design, additional testing will be conducted on Site soils.
Several soil samples will be collected and a range of Kd values will be
determine in order to confirm the RAO.
Table 9 presents the RAOs for soil based on the health-based risk goal and the
values determined for protection of groundwater using the two scenarios
mentioned above.
Actual of threatened releases of hazardous substances from the Site, if not
addressed by implementing the response action selected in this Record of
Decision (ROD), may present an imminent and substantial endangerment to
public health, welfare, or the environment.
7.0 DESCRIPTION OF REMEDIAL ALTERNATIVES
The following remedial alternatives were selected for evaluation:
* Alternative 1:
No-Action
-------
I I
ROD-OU2
ABC Site
Page 17
. Alternative 2:
Institutional Controls
. Alternative 3:
Copping
Soil Vapor Extraction (SVE)
. .
. Alternative 4:
. Alternative 5:
Demolition, Excavation and Low Temperature Thermal
Desorption (LTTD) .
7.1 Alternative] : No Action
CERCLA requires that the "No Action" alternative be considered. The no action
alternative provides the baseline for comparing existing site conditions with
those resulting from other proposed alternatives. It is also used to estimate the
potential risk to humans or the environment in the risk assessment.
Under this alternative, no additional remedial actions would be initiated
. beyond the groundwater remedial actions which' are covered under the OU-1'
ROD. There are no capitol costs with this alternative. Operating costs are
based on the review of the Site conditions every five years. There would be no
maintenance costs.
Total Capitol Costs
Present Worth O&M Costs
Total Present Worth Costs
$0
$170,000
$170,000
7.2 Alternative 2: Institutional Controls
Under this alternative, the institutional cqntrols which would be implemented
include property deed restrictions and land use resfrictions. Proper deed
notation involves annotating the site deed for affected properties to alert
prospective buyers to the presence of hazardous substances on-site. These
notations would be written to restrict future use of the property to non-
residential use. The restrictions would remain in place unless and until
contaminant concentrations were sufficiently reduced by natural processes to
allow for unrestricted use of the property.
Total Capitol Costs
Present Worth O&M Costs
Total Present Worth Costs
$62,500
$170,000
$232,500
-------
ROD-oU2
ABC Site
Page 18
7.3 Alternative 3: Capping
Under this alternative, a cap consisting of an asphalt cover would be placed
over. the contaminated soils that are present on the Site above the cleanup
levels. The existing buildings will remain in place. Along with the asphalt cap,'
a concrete seal would be placed over the floor inside the ABC cleaners
building to seal the cracks in the floor and to close the existing opening to the
in-ground sump. This seal would prevent further contamination from entering
the sump and/or the ground from the activities in the building.
The asphalt cap would be constructed to prevent contact with the
contaminated soils on the ABC property and along the driveway between
ABC Cleaners and Major Furniture. Although there is currentty an asphalt
cover over the driveway between the two buildings, there are several cracks
and holes, and the integrity of the cover is minimal. The asphalt cap would
also prevent the infiltration of rainwater from the surface into the ground, thus
further reducing the rate of migration of contamination to the groundwater.
Since this alternative does not reduce the contaminant concentrations in the
soils, deed restrictions and land use limitations are also included as part of this
option to ensure that the building and asphalt covers remain as effective
barriers.
Total Capital Costs
Present Worth O&M Costs
Total Present Worth Costs
$196,648
$179,069
$375,717
7.4 Alternative 4: Soli Vapor Extraction (SVE)
The SVE alternative involves the controlled application of an air pressure
gradient (direction of movement of air or water) in the vadose zone
(unsaturated) soils to induce an air flow through the soils contaminated with
volatile organic compounds (VOCs). The air pressure gradient in the vadose
zone soils would be created using a vacuum blower connected to a series of
air extraction wells or vents. As soil vapor is drawn through the soil toward the
extraction vents, the VOCs present in soil pore spaces in the vapor phase
would be removed, and the equilibrium between all the vac phases (free-
phase product, adsorbed phase, dissolved phase I and vapor phase) would be
upset, causing mass transfer into the vapor phase. .The VaC-laden vapor
removed from the soil through the extraction vents would be subsequently
treated (if necessary to comply with ARARs) using an off-gas treatment system.
-------
ROD-QU2
ABC Site
Page 19
Sealing for the concrete floor inside the ABC building, as mentioned in
Altemative 3, has been included as part of this altemative. The cap would
consist of a 4-inch concrete slab poured directly over the existing flooring to
cover the cracks in the flooring and close off the opening to the. sump. This
. would help prevent further contamination of the soils and groundwater due to
new process area spills or leaks. In addition, the cap would provide a'
continuous barrier to air flow in the SVE treatment zone to reduce .short-
circuiting. . '
The estimated volume of contaminated soil is 2,887..cubic yards. The
implementation time frame is estimated" as 12 months.
Total Capital Costs"
Present Worth O&M Costs
Total Present Worth Costs
$351 ,463
$170,000
$521,463
7.5 Altemative 5: Demolitionp IExcavation, Low Temperature Thermal Desorption
(~) .
Alternative 5 involves excavation and treatment of contaminated soils. It
consists of three principal steps. Demolition of the existing structures,
excavation of the contamination and treatment of the contaminated soils
using a low temperature thermal desorption (LTTO) unit. "
Following treatment, the soils would be tested for TCLP (Toxicity Characteristic
Leachate Procedure) characteristics and for total VOCs to determine the
appropriate handling method for the soils. Based on typical operations of the
LTTO system, and knowledge of the contaminants "present at the Site, it is
anticipated that the treated soils would have residl}al concentrations low
enough to allow the placement of the treated soils back into the excavated
area. Once the area has been backfilled and the treatment equipment
demobilized, the area would be seeded and left as an open field.
The estimated volume' of soil to be excavated is 4,210 cubic yards. The
implementation time frame is estimated as 12 months. "
Total Capital Costs
Present Worth O&M Costs
Total Present Worth Costs
$3,341,888
$ 30,745
$3,372,633
-------
ROD-OU2
ABC Site I
Paga 20
8.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
A detailed comparative analysis using the nine evaluation criteria set forth in
the NCP was performed on the five remedial alternatives developed during
the FS. The advantages and disadvantages were compared to identify the
alternative with the best balance among these nine criteria.
8.1 Threshold Criteria
8.1.1 Overall Protection 01 Human Health and the Environment
Section 8.1 . 1 addresses whether or not a remedy provides adequate
protection and describes how risks are eliminated, reduced, or controlled
through treatment, engineering controls, or institutional controls.
Alternative 1 does not eliminate any exposure pathway, does not reduce the
.Ievel of risk and does not protect the groundwater.
Alternative 2 does not provide for protection of human health if institutional
controls fail to prevent future higher risk site development. In addition, it will
result in continued migration to groundwater.
Alternative 3 is designed to reduce exposure to the contaminated soils, and to
reduce the migration of contaminants to the groundwater.
Alternatives 4 and 5 provide protection of human health and the environment
through treatment of the soils. Adequate protection will be provided during
remediation activities.
Since alternative 1 does not eliminate, reduce or control any of the exposure
pathways and is not protective to the groundwater; and alternative 2 is not
protective of groundwater, they are therefore not protective of human health
and the environment and will not be considered further in this analysis.
8.1.2 Compliance with Applicable or Relevant and Appropriate Requirements
(ARARs)
Section 8.1.2 addresses whether or not a remedy wjll meet all of the applicable
or relevant and appropriate requirements of other Federal and State
environmental statutes and/or provide grounds for a waiver. The identified
ARARs for this Site are listed in Section 9.3
-------
I I
ROD-QU2
ABC Site
Page 21 .
ARARS will be met under Alternatives 3, 4 and 5.
8.2 jplrRmCiry Balglillcftlng Criteria
8.2.1 Long-Term Effectiveness and Permanence
Subsection 8.2.1 refers to expected residual risk and the ability .of a remedy to
maintain reliable protection of human health and the environment over time,
once cleanup levels have been met. This criterion includes the consideration. of
residual risk and the adequacy and reliability of controls. .
Alternative 3 will require long-term maintenance of the cap, deed restrictions
and land use restrictions, since the contamination will remain virtually
unchanged. .
Alternative 4 will also require some degree of long term maintenance and
deed restrictions because some contamination will remain at the site.
Alternative 5 offer long-term effectiveness and permanence through treatment
of the contaminated soils.
8.2.2 Reduction 01 Toxicity, Mobility, or Volume Through Treatment
This subsection refers to the anticipated performance of the treatment
technologies a remedy may employ. .
Alternative 3 reduces the mobility of soil contaminants as long as the cap is
intact, but not their toxicity or volume.
Alternatives 4 and 5 offer contaminant toxicity reduction through treatment of
the contaminated soils. There would be no significant risk remaining at the site
due to the vac concentrations in the soils upon completion of the remedial
actions, even for Mure residential use.
8.2.3 Short-Term Effectiveness
Short-term effectiveness refers to the period of time needed to complete the
remedy and any adverse impacts on human health and the environment that
may be posed during the construction and implementation of the remedy until
cleanup levels are achieved.
Alternative 3 and 4 may require some dust suppression measures during
-------
ROD-OU2
ABC Site
Page 22
construction due to possible particulate emissions.
Altemative 5 offers the lowest degree of short term effectiveness due to the
intrusive soil removal activities.
8.2.4Implementability
Implementability is the technical and administrative feasibility of a remedy,
including the availability of materials and services needed to implement the
chosen solution.
Altemative 3 and 4 offers a relatively high degree of implementability with
some possible access limitations.
Altemative 5 offers major limitations due to the nature of the treatment
activities. Demolition activities would require cessation of the business and
acquisition of the adjacent property.
8.2.5 Cost
The total Present Worth Costs for the alternatives evaluated are as follows:
Altemative 1: $ 170,000
Altemative 2: $ 232,500
Altemative 3: $ 375,717
Altemative 4: $ 521,463
Alternative 5: $ 3,372,633
8.3 Modifying Criteria
8.3.1 State Acceptance
EPA and the North Carolina Department of Environment, Health, and Natural
Resources (NCDEHNR) have cooperated throughout the RifFS process. The
State has participated in the development of the RifFS through comment on
each of the various reports developed by EPA, and the Draft ROD and through
frequent contact between the EPA and NCDEHNR site project managers. EPA
and NCDEHNR are in agreement on the selected alternative. Please refer to
-------
ROD-QU2
ABC Sits
Page 23
the Responsiveness Summary which contains a letter of concurrence from
NCDEHNR. '
8.3.2 Community Acceptance
EP A solicited input from the community on the Proposed Plan for clean-up of
the ABC Site. Although public comments indicated no specific opposition to
the preferred altemative, some local residents express their concerns during
the Proposed Plan public meeting. Please see the Responsiveness Summary
which contains a transcript of the public meeting.
9.0 THE SELECTED REMEDY
Based upon consideration of the CERCLA requirements, the NCP, the detailed
analysis of the altematives using the nine criteria, and public and state
comments, EPA has selected a source remedy for this Site. At completion of -
this remedy the soil risk associated with the Site will be below acceptable
levels, protective to groundwater, and to human health and the environment.
The total present worth cost of the selected remedy, Alternative 4, is estimated
at $521,463.
Source control: Treatment of in-situ materi01~
Source control remediation will address the contaminated soils at the Site.
The contaminated soil will be treated in-situ using a SVE system. The estimated
volume of contaminated soil is 2887 cubic yards. The implementation time
frame is estimated to take 12 months.
The SVE system involves the controlled application of an air pressure gradient in
the vadose zone (unsaturated) soils to induce an air flow through the
contaminated soils. The air pressure gradient in the vadose zone soils could be
created using a vacuum blower connected to a series of air extraction wells or
vents. As soil vapor is drawn through the soil toward the extraction vents, the
vacs present in soil pore spaces in the vapor phase would be removed, and
the equilibrium between- all the vac phases (free-phase product, adsorbed
phase, dissolved phase, and vapor phase) would be upset, causing mass
transfer into the vapor phase. The VaC-laden vapor removed from the soil
through the extraction vents would be subsequently treated (if it is necessary)
using an off-gas treatment system, such as granular activated carbon (GAC),
thermal oxidation, or any other treatment system to ensure that ARARs are
met.
-------
ROD-OU2
ABC Site
Page 24 I
Measures to prevent further contamination due to new process area spills or
leaks shall be taken. A measure that could be considered Is sealing the
concrete floor inside the ABC building, pouring a concrete slab directly over
the existing flooring to cover the cracks in the flooring, and closing of the
opening to the sump. The specific measures that will be implemented will be
determined during design.
Emission Control
A GAC adsorption system, a thermal oxidizer or any other emission control
system, if necessary, will be used to treat the off-gas from the SVE treatment
system. The emission control system that will be used at the Site will be
determined during remedial design and it shall be in compliance with Federal
and State standards.
9.1 Performance Standards
The performance standards for the selected remedy include, but are not
limited to the following standards:
9.1. 1 Treatment Standards
Soil will be treated in manner that reduces concentrations of the following
contaminants of concem to the levels specified below.
T etrachloroethene (PCE)
Trichloroethene (TCE)
1 ,2 DC Ectotao
Vinyl chloride
2.16 mg/kg
0.90 mg/kg
21.00 mg/kg
0.03 mg/kg
9.1.2 Additional Sampling
A very conservative model and assumptions were used to calculate the soil
treatment standards listed in section 9.1.1. During remedial design, additional
data will be collected in order to verify the assumptions and confirm the results
of the model.
9.2 Site specific ARARs
9.2.1 Applicable Requirements
The remedy will comply with all the applicable portions of the following Federal
-------
ROD-OU2
ABC Site
Page 25
and State regulations.
~, 262, 263, 264, anq 268 promulaated under the authoritLQf
1lliLResburce. Conservatjon and_Recovery Ac~. These regulations are
applicable to the management of hazardous waste, Including treatment,
storag~ and disposal. .
40 CFR Parts 50 and 61 romul ated under the authori of the Clean Air Act.
These regulations apply to the emissions of pollutants into the ambient .
atmosphere.
North Carolina Administrative Code NCAC Title 15A Cha ter 13A
Reaulations for the Manaaement of Hazardous Waste promulaated under the
autho' of NC Waste Mana ement Act. These regulations are applicable to .
the management of hazardous, waste in the State of North Carolina.
NCAC Title 15A, Chapter 138, Reaulations for disposal of Solid Waste
promu!9Qj"ed under the au~azarqous Waste Commission Act.
These regulations are applicable to the management of solid waste in the
State of North Carolina.
NCAC Title 15A, Chapter 2, Subchapter 2D Reaulations aovemina emissions of
ollutants to Air' Ambient Air Quali Standards romul atad under the
authori of the NC Water and Air Resources Act. These regulations are
applicable to air emissions of pollutants in the state of North Carolina.
NCAC Title 15A, Chapter 2, Subchapter 2L Reaulations aovemina
classifications and water auaUJv standards applicaole to aroundwater,
promu~ under the au~C Water and AIL-Resources Act. These
regulations are applicable to the protection of groundwater in the state of
North Carolina
10.0 STATUTORY DETERMINATIONS
Under CERCLA Section 121, EPA must select remedies that are protective to
. human health and the environment, comply with applicable or relevant and
appropriate requirements (unless a statutory waiver is justified), are cost-
effective, and utilize permanent solutions and altemative treatment
technologies or resource recovery technologies to the maximum extent
practicable. In addition, CERCLA includes a preference for remedies that
-------
ROD-OU2
ABC Site
Page 26
employ treatment that permanently and significantly reduce the volume,
toxicity, or mobility of hazardous waste as their principal element. The following
sections discuss how this remedy meets these statutory requirements.
10.1 Protection of Human Health and the Environment
No short-term threats are associated with the selected remedy that cannot be
readily controlled. In addition, no adverse cross-media impacts are expected
from the remedy.
. 10.2 Compliance with Applicable or Relevant and Appropriate Requirements
The selected remedy will be in full compliance with all applicable or relevant
and appropriate requirements (ARARs). A complete discussion of these ARARs
which are to be attained is outlined in Section 9.3
10.3 Cost Effectiveness
The selected remedy, Alternative 4, was chosen because it provides the best
balance among criteria used to evaluate the alternatives considered in the
Detailed Analysis. The alternative was found to achieve both adequate
protection of human health and the environment and to meet the statutory
requirements of Section 121 of CERCLA. The selected remedy was found to be
cost-effective when compared to other acceptable alternatives. The cost of
Alternative 4 has been estimated to be $ 521 ,463. .
10.4 Utilization of Permanent Solutions and Alternative Treatment Technologies
or Resource Recovery Technologies to the Maximum Extent Practicable
EPA and NCDEHNR have determined that the selected remedy represents the
maximum extent to which permanent solutions and treatment technologies
can be utilized in a cost-effective manner. Of those alternatives that are
protective of human health and the environment and comply with ARARs, EPA
and NCDEHNR have determined that the selected remedy provides the best
balance of trade-offs in terms of long-term effectiveness and permanence,
reduction of toxicity, mobility, or volume achieved through treatment, short-
term effectiveness, implementability and cost, while also considering the
statutory preference for treatment as a principal element and considering
State and community acceptance.
The selected remedy treats the principal threats posed by contaminated soils,
achieving significant contaminants reductions. This remedy also provides the
-------
- - >"
ROD-OU2
ABC Site
Page 27
. most effective treatment of any of the altematives considered.
10.5 Preference for Treatment as a Principal Element
By treating the contaminated soil by SVE, the selected remedy addresses the
principal threats pos'ed by the soil at the Site through the use of treatment
technologies. By utilizing treatment as a significant portion of the remedy, the
statutory preference for remedies that employ treatment as a principal
element is satisfied.
-------
APPENDIX A
LIST OF FIGURES
-------
r-- .-
II
Agure 1 - Site Location Map
r,.,o"
. .
UN
u'
_.'~.~~~.
. .
It-.'.
I
r ASC OMf-HOUR CUA~!'"
'W
. ~
Nt
'.
. UJ£Ut(
tUUVAUCI(
..
~
...
"
u'
. \
I.~
a
,.. UJ(1,.Io(
?~~
ON&4.OC
<:ouom'
I &..~
-------
Rgure 2 - Base Map for Cross Section A-A I and B-B I
~~
A
....~
"C Co
CAup I.£JEUUE
LIJ,R(l(£ CORPs '&....sE
~
n-tJ Co I'RAWA ~ ~ WA!'[R SUPPlY WEll.
nt~. ~ SUI'Pl.Y WEU.
., Co ~ S1J~ J>l:/IJIffR IIONITOQ IO.Ul.
C f. [XIS TIN, CASTU: KA TN( .<.I;Uf"[)t IIOffifOR WEU.
"10 ICEWl.Y t
-------
Agure 3A - Cross Section A-A'
A
~ :
~ .
--
I::
g':
-4.
1-4-
5-'.
I (30.80)
51 (30.58)
5B4 (31.75)
CIO (3%.SO)
53 (3U$)
C3 (»'40)
C2 (32.02)
52 (32.4e)
INRRBU»U IUNDS. SJLrS AND CUI'3
QI1.Utft &IND
'lD'UODS 'D CJ.STUl1lAJ?l6 AOrruU.
. Jl1Ql1J' CDaNTD 1'OSsruTU/K/$ $JJl1I
- - - - 70siii8iiiUs SiHiT W - - - - -
O'
I
100
I
400
.
HORIZONTAL SCAL£
V£RrrCAL UACC6/UrrON - sx
CLinY $AND
8/UT $AND
SURF1t:ZA1. ~azn1t
LeceND
I
UTHOLDCJC CtJNTAC1' (DASHrD rH£RZ IN,tAAU)
SUIVICIAL AQUUL'Vt:AS1U RAYNZ AQUl1VI. tX1NTACT
(A4SHVJ rmvu JNF£RlUD)
DEP1'H-ro-FAfV. BUDr CRDUND SII1VACE
JltASUUJ) IN nus: "/111"
!
BE/ITONITZ Sl.A.L.S.AND PACK AJlD rZLL SCRElN
CI (30.80) rru. NTlJ/B611 (t;J/.()1JN1) StlJI/'AU 6UVArrON. IN TZU J/SL)
$14 (31.75) SOlL BORJ}{(; NI/JlUII (C/U)/J1(D SlJ1VAce IUVAr10N, IN FEET J/SL)
3
-------
Rgure 3B - Cross Section B-B'
B
QC1AJt17 $IJflJ
&lUY SAND
rossn.uVlOClS SAND
AJ(1J c:AA ~L
C(S1'LI; IU YNE AqW £R
(ATlOH (FUT. l.lEAN SEA l£VEL)
0'
I
7:1'
I
1:10'
I
HORIZONTAL SCAL£
YV/.rIcu. D:l.c(;zRArIOH - a
(33.0~)
U (n.U)
\' (32.7~)
INTZlUJtmJE.O SANIJS..
= AJ(1J =
~
SURnCLU. ,AqUUVl
SJL1'Y ~
HlCHLT Ct;JaxnD TOSSI1DEROUS SI.)(D
L£GEND
LlTHOLOCJC a»rrACT (A4SHZD fflZJU /NT L'UUD)
SU1VJCLU. ,AqUU£R/CASTU lLI.YNI AQUT'U. a»rrACT
(DASHZJJ rJaRl Dl/'EJ/RE.J))
DEPn/ - 10- r.uTR . ELOr CRt!CINJ) SURFACE
lIUSURZ.D IN nLL3 11/16/'"
t
I
BENTONITE SLU.,SAND PAC}( AND ITEU SClUEN
CI (30.10) 'flU NUJlJJ£R (CMUND SUIU'ACE CUYArIO)(, {}/ FEET lISL)
SU (31.75) SOIL BOJWIC NlIJlBE.R (CRI)WD SURFACE UCYArrON. IN FEEr IISL)
4
B/
Ct (32. U)
f
-------
Agure 4 - locations of Temporary Monitoring wells Installed by NRCD in 1985
.M~
fl...
~
. CAMP LEJEUNE
UARINE CORPS SASE
. .
U:QQC):
A n-u-'AMWA ftMA~ CCUoUtrr
MrLY toCU.
... -1tWOIIMT MONI1o.- 'G&.
MfAWD tY IIIaIIC .....
5
-
H
~.
-.. . 1m
-------
NORTH
Rgure 5 - Soil Borin-g Locations
LEGEND
4 VI
a SPMI
058-11
. GT-[
o S8 -"
58-4
o
~
58 - .3
o
o
S8-15
o
S8-23
AV2
o 0 ~
5PM4 05PM2
o 5PM1
. 0
GT-W 58-2
o
8-22
o
SPM5
A
VI
o
58-14
58-2
o
o
58-19
58-1
o
LEGENDS
TAVERN
o
S8-16
o
58-13
ABC
1-HOUR CLEANERS
MAJOR
FURNITURE
o
58-6
o
58-5
SOIL VAPOR EXTRACTlON BORING LOCA TlONS
SOIL PRESSURE MONITOR BORING LOCA TlONS
OU-2 SOIL BORING LOCATlONS
GEOTECHNICAl BORING LOCA TlONS
OU -1 SOIL BORING LOCA TlONS
o 5
25
50
~ -......
SCALE IN FEET'
6
-------
APPENDIX B
LIST OF TABLES
-------
Table 1
Results or Analyses or Septic Tank Samples
For Volatile Organic Compounds
ABC One-Hour Cleaners Operable Units 1 and 2
Parameter SS-Ol1-01 SS-Ol1-02 ST -02
6/29/91 6/29191 9122/93
Vinyl Chloride 4,000 7,900 J < 16,000,000
Cis-I,2- Dichloroethene 6,700 63,000 < 16,000,000
Chloroform < 2,000 < 10,000 < 16,000,000
Trichloroethene 840 J 3,400 J < 16,000,000
Bromodichloromethane < 2,000 < 10.000 < 16,000,000
Tetrachloroethene 6,800 230.000 < 250,000,000
Dibromomethane < 2,000 < 10.000 < 16.000,000
Notes:
SS-Ol1-01 and SS-011-02 units are micrograms per liter ijJgIl).
ST-02 units are micrograms per kilogram ijJgJkg).
55-011-01 was sampled from liquid phase.
SS-011-02 was sampled from sludge phase.
< indicates that a material was analyzed for but not detected.
the minimum quantitation limit. .
J indicates an estimated value.
The reported value is
-------
Table 2
Soil Sample Analysis Results Summary
ABC One-Hour Cleaners
Operable Unit 1 (June 1991) and
Operable Unit 2 (September 1993)
Contaminant Concentrations I
Sample Tetrachloro- l,2,-Dichloroethene Vinyl Chloro-
Identifialtion J ethene Tri-chloroethene (total) Chloride form 1,1-Dichloroethene
SSOOl-OI-06* 640 96 95 <57 <29 <29 l
'-
S5001-0I-l0* 37 2J <6 <11 <6 <6
--
SS 0111 -01-14* 4-W 161 <2X <56 <28 ------ -
5S (1(12 01 0(-,* 72 200 42
SS003-01-14* <29 <29 <29 <58 <29 <29
SS-U04-01-12* <6 <6 <6 <12 <6 <6
SSI)04-01-16* <6 <6 <6 <12 <6 <6
_-
SS-00'i-0106* 31 <(, <(, <13 <6 <6
--- --
55005-01-12* <6 <6 <6 <13 <6 <6
55006-01-12* <6 <6 <6 <12 <6 <6
55-006-01-14* <7 <7 <7 <13 <7 1 <7
~._-
m
!
- ~~
-------
Table 2 (Continued)
Contaminant Concentrations 1
Sample Tetrachloro- l,2,-Dichloroethene Vinyl Chloro-
Identification J ethene Tri-chloroethene (total) Chloride form l,l-Dichloroethene
SS-007 -01A-10. <6 <6 <6 <11 <6 <6
SS-007-018-10. <6 <6 <6 <12 <6
-------
T;>hle 2 i Contmued)
I ~---=i
Contaminant Concentrations 1
, !
Sample Tetrachloro- 1,2,-J)ichioroethcne Vinyl Chloro-
Identification J cthene Tri-chlorocthcnc (total) Chloride form 1_~~I_~~~~~OdhCIlCJi
55-014-03-10 210 <12 r-----l
12 <12
-------
Table 2 (Continued)
Contaminant Concentrations 1
Sample Tetrachloro- 1 ).,- Dichloroethene Vinyl Chloro-
Identification J ethene Tri-chlo: oethene (tota I) Chloride form 1,l-Dichloroethene
55-019-02-05 4900 1400 3100 190 <12 <12
55-019-03-09 16 <12 <12 <12 <12 <12
55-019-04-15 5100 <1,400 840J <1.400 <1,400 < 1.400
..
55-020-01-00 56 <11 <11 <11 <11 <11
55-021-01-00 170 14 <11 <11 <11 <11
55-021-01-ooA 94 14 <11 <11 <11 <11
55-022-01-02 580000 15000 720 <7,000 <7,000 <7;000
55-022-01-02A 790000 <130,000 <130,000 <130,000 <130,000 <130,000
55-022-02-05 21000 lOOOJ 2400 <1,500 <1,500 <1,500
55-022-03-10 26000 1700 3700 <1.500 <1,500 <1.500
55-022-04-15 2900 <1,400 670J <1,400 < 1,400 < 1,400
55-023-01-02 410001 . 36001 851 <14 <14 <14
55-023-02-05 120 22 121 <12 <12 <12
55-023-03-10 20 14 37 <13 <13 <13
55-023-04-15 44 85 '-- 180 <12 <12 <12
55-024-01-00 <5,400 4401 <1.400 <1,400 <1.400 <1,400
55-024-02-05 <1,400 <1,400 <1,400 <1.400 <1,400 < 1 ,400
55-024-03-10 <1,900 190J <1,400 <1.400 <1.400 <1,400
55-024-04-15 <3,000 2701 4601 <1,400 <1,400 <1,400
T -5
-------
Table 2 (Continued)
Contaminant Concentrations 1
Sample Tetrachloro- 1,2,-Dichloroethene Vinyl Chloro-
Identification 1 ethene Tri-chloroethene (total) Chloride form l,l-Dichloroethene
SS-SPMI-Ol-OO 49000 10001 9401 < 1 ,400 < 1,400 <1,400
SS-SPMI-02-05 7500 7901 1500 <1,400 < 1,400 <1,400
SS-SPM 1-03-1 0 7100 5301 12001 < 1,400 <1,400 < 1 ,400
SS-SPMI-04-14 8900 7801 , 1800 <1,400 < 1 ,400 < 1 ,400
SS-SPM2-01-00 4400 7301 9001 < 1,3 00 <1,300 < 1,3 00
SS-SPM2-02-05 1 1000 1600 2300 < 1,400 <1,400 < 1 ,400
SS-SPM2-02-05A 14000 2200 3100 <1,500 <1,500 < 1.5 00
SS-SPM2-03-1O 15000 1500 2000 <27 <27 <27
SS-SPM2-04-15 6000 <1,400 <1,400 <1,400 < 1 ,400 < 1 ,400
SS-SPM5-01-00 43000 <2,500 <2,500 <2.500 <2,500 <2,500
SS-SPM5-02-05 1 1000 <12 5100 79 <12 <12
SS-SPM5-03-1O 3000 <1,400 < 1 ,400 < 1,400 <1,400 <1,400
SS-SPM5-04-15 13000 < 1,300 9901 <1,300 <1,300 < 1,300
SS-VI-Ol-IO 33000 8101 12001 <1,400 < 1 ,400 <1,400
SS-YI-02-14 47000 1700 3000 < 1 ,400 < 1 ,400 < 1 ,400
SS-YI-02-14A 180000 11001 <1,400 < 1 ,400 < 1 ,400 < 1 .400
SS-Y2-01-02 1800001 360001 200001 <20 <20 291
SS- Y2-02-05 54001 510 370 <39 <39 <39
SS-Y2-03-1O 580 91 83 <12 <12 <12
T -6
-------
Table 2 (Continued)
Contaminant Concentrations 1
Sample Tetrachloro- l,2,-Dichloroethene Vinyl Chloro-
Identification 2 ethene Tri-chloroethene (total) Chloride form l,l-Dichloroethene
SS-V2-03-10A 2300 110 95 <12 <12 <12
SS-V2-04-14 800 120 100 <12 <12 <12
I concentration reponed in ~glkg - micrograms per kilogram
2 indicates depth of sample bgs .
* - QUI samples collected June 1991. KEY: 55-001-01-06 is nomenclature for soil sample; soil boring number; Operable Unit I; sample collection depth.
55-016-01-015 is nomenclature for soil sample; soil boring number; sampling interval; and sample collection depth.. .
J - estimated value
< - not detected above identified quantitation limit
T -7
-------
Table 3
Contaminants of Concern
(mg/"kg)
---<---~
Chemical Frequency of Detection Range of Detection Mean Concentration
Chlorofonn ' 2/55 0.Ql - 0.017 0.014
1,I-Dichloroethene' 1/55 0.029 NA
1,2-Dichloroethene 35/55 0.012 - 110 5.0
Tetrachloroethene 46/55 0.01 - 2,100 86
Trichloroethene 36/55 0.002 - 260 14
--~
Vinyl Chloride 2/55 0.079 - 0.19 0.135
NA - Not Applicable, detected only once.
'" Chlorofonn and 1,1 DeE will not be considered further in this ROD because both contaminats have a
very low frequency of detection and in both cases the maximum concentration detected is below the
remediation level calculated.
T-8
-------
Table 4A
Exposure Point Concentrations
For Current On-Site Work. ,
(mglkg)
Potential Chemical of Maximum D,eWctioD '." Upper Confidence Exposure Point
Concern Limit Concentration
Tetrachloroethene 2,100 12,300 2,100
Trichloroethene 33 17,994 33
. = Includes soil samples from depth of 0 to 1 feet outside ABC building.
> = greater than the identified quantitation limit
T -9
-------
Table 48
Exposure Point Concentrations
For Future Resident!
(mg/kg)
Potential Chemical of Maximum Detection Upper Confidence Exposure Point
Concern Limit Concentration
1,2- Dichloroethene 20 15,789 20
Tetrachlorocthene 2,100 1,300,000 2,100
Trichloroethene 120 1,150,000 120
! = Includes all soil samples from depth of 0 to 1 feet.
> = greater than the identified quantitation limit
T -10
-------
Table 4C
Exposure Point Concentrations
For Future Construction Worker!
(mglkg)
Potential Chemical of Maximum Detection Upper Confidence Exposure Point
Concern Limit Concentration
1,2- Dichloroethene 110 48 48
Tetrachloroethene 2,100 10,939 2,100
Trichloroethene 260 83 83
Vinyl Chloride 0.19 9.1 0.19
I = Includes all soil samples at all depths~
T -11 .
-------
Table SA
Model for Calculating Doses from
Incidental Ingestion of Soil
Soil Ingestion Dose = CS x IR x CF x EF x ED
(mglkg-day) BW x AT
Where:
CS = Chemical concentration in soil (mglkg)
IR = Soil ingestion rate (mg/day)
CF = Conversion factor (lE-6 kg/mg)
EF = Exposure frequency (days/year)
ED = Exposure duration (years)
BW = Body weight (kg)
AT = Averaging time (days)
Assumptions:
CS = The reasonably maximum exposure concentration in soil (Tables 7-2 through 7-4).
IR = 200 mg/day for the future child (1-6) resident (EPA, 1991a).
100 mg/day for the future youth resident (7-16) (EPA, 1991a).
100 mg/day for the future adult resident (EPA. 1991a).
50 mg/day for the current and future worker (EPA, 1991a).
EF = 350 days/year for the future children, youth, and adult residents (EPA. 1991a).
250 days/year for the.current and future worker (EPA, 1991a).
ED = 0.5 years for the future on-site construction worker.
6 years for the future child (1-6) resident (EPA, 1991a).
10 years for the future youth (7-16) resident (EPA. 1991a).
14 years for the future adult resident (EPA. 1991a).
= 25 years for the current on-site worker (EPA. 1991a).
BW = 15 kg for the future child resident (EPA, 1991a).
45 kg for the future youth resident (7-16) (EPA, 1991a)
70 kg for the future adult resident (EPA, 1991a).
70 kg for the current and future worker (EPA, 1991a).
AT = Exposure duration (years) x 365 days/year for evaluating noncancer risk.
= 70 years x 365 days/year for evaluating cancer risk.
T -12
-------
T2Ible 5B
Model for Calculating Doses from
Dermal Contact with Soil
Soil Dermal Absorption Dose = CS x CF x SA x AF x ABS x EF x ED
(mg/kg-day) BW x AT
Where:
CS = Chemical concentration in soil (mglkg)
CF = Conversion factor (1E-6 kg/mg)
SA = Skin surface area available for contact (cm2/day)
AF = Soil to skin adherence factor (mg/cm2) -
ABS = Dermal absorption factor (unitless)
EF = Exposure frequency (days/year)
ED = Exposure duration (years)
BW - Body weight (kg)
AT = Averaging time (days)
Assumptions:
CS = Tbe reasonably maximum exposure concentration in soil (Tables.7-2 through 7-4).
SA = 2,125 cm2/day for the future child (1-6) resident. It represents the 50th percentile surface
area of the. arms, hands, lower legs, and feet (50% of the exposure events) and forearms and
. hands (50% of the expom events) of a 1-6 year old (EPA, 1985).
= 4,397 cm2/day for the futOre youth (7-16). It repres~nts the 50th percentile surface area of
the arms, hands, lower legs, and feet (100% of the exposure events) (EPA, 1985).
= 4,145 cm2/day for the future adult resident It represents the 50th percentile surface area of
the arms, hands, lower legs, and feet (50% of the exposure events) and forea.rms and hands
(50% of the exposure events) of an adult male (EPA, 1985).
= 1,980 cm2/day for the current and future worker. It represents the 50th percentile surface
area of the fQrearms and hands of an adult male (EPA, 1985).
AF = 0.6 mg/cm2, soil adherence factor (EPA, 19918).
ABS = 0:01 - Organic compounds (EPA, 1992)
0.001 - Inorganic compounds (EPA, 1992).
EF = 350 days/year for the future child, youth, and adult residents (EPA, 199Ia).
250 days/year for the current and future worker (EPA, 199Ia).
ED = 0.5 years for the future on-site construction worker.
6 years for the future child (1-6) resident (EPA, 199Ia).
10 years for the future youth (7-16) resident (EPA, 1991a).
2S years for the on-site current worker (EPA, 1991a).
- 14 years for the adult resident (EPA, 199Ia).
T -13
-------
Table 5B (Continued)
Model for Calculating Doses from
Dermal Contact with Soil
Soil Dermal Absorption Dose = CS x CF x SA x AF x ABS x EF x ED
(mg/kg-day) BW x AT
Where:
CS = Chemical concentration in soil (mg/kg)
CF = Conversion factor (lE-6 kglmg)
SA = Skin surface area available for contact (cm2/day)
AF = Soil to skin adherence factor (mg/cm2)
ABS = Dermal absorption factor (unitless)
EF = Exposure frequency (days/year)
ED = Exposure duration (years)
BW = Body weight (kg)
AT = Averaging time (days)
BW = 15 kg for the future child resident (EPA. 1991a).
45 kg for the future youth (7-16) resident CEPA, 1991a)
70 kg for the current, future worker and future adult resident (EPA. 1991a).
AT = Exposure duration (years) x 365 days/year for evaluating noncancer risk.
= 70 years x 365 days/year for evaluating cancer risk.
T -14
-------
I
I I
I,
I
Table 6
EPA Weight-of-Evidence Classification System for
Carcinogenicity
-~
A Human carcinogenic
B 1 or B2 Probable human carcinogenic
B 1 indicates that limited data are available.
B2 indicates sufflcient evidence in animals and inadequate or no evidence
in humans.
C Possible humans carcinogen ,
D Not classifiable as to human carcinogenicity
E Evidence of human noncarcinogenicity for humans
T -15
-------
Table 7
Carcinogenic Chemicals of Concern
and Their EPA and IARC Classification
Chemical
EPA Carcinogenicity
Classification
IARC Carcinogenicity
Classification
Tetrachloroethene
Trichloroethene
2B
3
Vinyl Chloride
A
1 Cancer classifiration under review.
T -16
-------
Table 8
Health Criteria
Contaminants of Concern in SoU
Chemical Oral Slope Reference Dermal Oral Reference DG!mmll
Factor Slope Reference RefereIIllc!e
(mg/kglday)-l Factor Dose DoW
(mg/kglday)
1 ;l-Dichloroethene NTV -- -- 1 X 10-2 IRIS. 1993 8 x 10"'
Tetrachloroethene 5.2 x 10-2 ECAO 6.5 x 10-2 1 X 10-2 IRIS. 1993 8 x l()"'
Trichloroethene 1.1 x 10-2 ECAO 1.4 x 10-2 6 X 1(}"' IRIS. 1993 4.8 x 1(}"3
Vinyl Chloride 1.9 x 1(f . HEAST 2.4 x 100 NT'i -- --
NTV = No Toxicity Value.
ECAO = Environmental Criteria Assessment Office. Cincinnati, Ohio
I The dermal CSF was derived based on the following Absorption Factors (ABS):.
0.2 - Inorganics
0.8 - Volarile Organics
0.5 - Semi-Volatile OrganicsIPesticidesJPCBs
Dennal Slope Factor = Oral SF lABS
2 The dermal RID was derived based on the following Absorption Factors (ABS):
0.2.Inorganics
0.8 - Volarile Organics
0.5 . Semi-Volatile Organics/PesticidesJPCBs
Dennal RID = Ornl RID x ABS
T ..,17
-------
Table 9
Remedial Action Objectives ror Contaminants or Concern
Contaminant Risk-Based Protection or Protection or
Groundwater groundwater
(Structures in place) (Structures removed)
-
Tettachloroethene (PCB) 10.5 2.16 0.61
Trichloroethene (TCE) 40 0.90 0.26
1,2 I>CI; total) NA 21.0 5.98
Vinyl Chloride NA 0.03- 0.0089
All results are presented in units of milligrams per kilogram (mg/kg)
NA = Not applicable. Risk associated with this compound at the maximum soil concentration detected was below lxlo-6 excess
cancer risk and hazard index of I.
. u.s. GOVERNMENT PRINTING OFFICE: 1994-386-541/03072
T -18
-------
|