964773
Record of Decision
Pike and Mulberry Streets PCE Plume
Superfund Site
Martinsville, Morgan County, Indiana
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U.S. Environmental Protection Agency
Region 5
Chicago, Illinois
March 11, 2021
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Table of Contents
LIST 01 ACRONYMS/ABBREVIATIONS 4
Part I: Declaration 6
Site Name and Location 6
Statement of Basis and Purpose 6
Assessment of Site 6
Description of the Selected Remedy 6
Statutory Determinations 7
Support Agency Acceptance 8
Authorizing Signature 8
Part II: Decision Summary 9
1.0 Site Name, Location and Description 9
2.0 Site History and Enforcement Actions 9
4.0 Scope and Role of Operable Unit 13
5.0 Site Characteristics 13
6.0 Current and Potential Future Land Use 21
7.0 Summary of Site Ri sks 21
8.0 Remedial Action Obj ectives 24
9.0 Description of Alternatives 25
10.0 Comparative Analysis of Alternatives 41
10.1 Comparative Analysis of Groundwater Alternatives 42
10.2 Comparative Analysis of Soil Vapor Alternatives 46
12.0 Selected Remedy 49
12.1 Summary of the Rationale for the Selected Remedy 49
12.2 Description of Remedial Components 51
12.3 Summary of the Estimated Remedy Costs 52
12.4 Expected Outcomes of the Selected Remedy 52
13.0 Statutory Determinations 52
13.1 Protection of Human Health and the Environment 53
13.2 Compliance with ARARs 53
13.3 Cost-effectiveness 53
13.4 Utilization of Permanent Solutions and Alternative Treatment Technologies (or
Resource Recovery Technologies) to the Maximum Extent Practicable 53
13.5 Preference for Treatment as a Principal Element 54
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13.6 Five-Year Review Requirements..
14.0 Documentation of Significant Changes
Part III: Responsiveness Summary
54
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56
Figure 1 - Site Location Map
Figure 2 - PCE Exceedances in Shallow Groundwater - Phase 3
Figure 3 - PCE Soil Vapor Results (Phases 2 through 6)
Figure 4 - TCE Soil Vapor Results (Phases 2 through 6)
Figure 5 - Soil Sample Results from PCA for Master Wear Removal
Figure 6 - Conceptual Site Model - PCE in Groundwater and Soil Vapor
Figure 7 - Conceptual Site Model - TCE in Groundwater and Soil Vapor
Figure 8 - Conceptual Site Model - PCE and TCE in Soil
Figure 9 - Site Features and Land Use
Appendix A - Administrative Record Index
Appendix B - ROD Concurrence Letter from IDEM
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LIST OF ACRONYMS/ABBREVIATIONS
ADT Active Depressurization Technology
AR Administrative Record
ARAR Applicable or Relevant and Appropriate Requirement
AS Air Sparging
ATSDR Agency for Toxic Substances and Disease Registry
bgs Below Ground Surface
BHHRA Baseline Human Health Risk Assessment
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
C.F.R. Code of Federal Regulations
The City City of Martinsville, Indiana
ci s-1,2-D CE ci s-1,2-di chl oroethene
cm/s Centimeters Per Second
COC Contaminant of Concern
CSM Conceptual Site Model
DPT Direct-Push Technology
ELCR Excess Lifetime Risk of Cancer
EPA United States Environmental Protection Agency
°F Degrees Fahrenheit
FS Feasibility Study
ft/yr Feet Per Year
GAC Granular Activated Carbon
HHRA Human Health Risk Assessment
HI Hazard Index
HVAC Heating, Venting, and Air Conditioning
IC Institutional Control
IDEM Indiana Department of Environmental Management
ISCO In-Situ Chemical Oxidation
ISCR In-Situ Chemical Reduction
LTM Long-term Monitoring
MCL Maximum Contaminant Level
MNA Monitored Natural Attenuation
NAPL Non-Aqueous Phase Liquid
NCP National Oil and Hazardous Substances Contingency Plan
NPL National Priorities List
O&M Operation and Maintenance
OM&M Operation, Maintenance, and Monitoring
ORP Oxidative, Reductive Potential
P&M Site Pike and Mulberry Streets PCE Plume Site
PCA Pre-Closure Assessment
PCE Tetrachl oroethene
PRG Preliminary Remediation Goal
PRP Potentially Responsible Party
RAO Remedial Action Objective
RI Remedial Investigation
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ROD
Record of Decision
SDWA
Safe Drinking Water Act
Site
Pike and Mulberry PCE Plume Site
SL
Screening Level
SLERA
Screening Level Ecological Risk Assessment
SMD
Submembrane Depressurization
SSD
Sub-Slab Depressurization
SVE
Soil Vapor Extraction
SVP
Soil Vapor Point
TCE
Trichloroethene
TCRA
Time-Critical Removal Action
UU/UE
Unlimited use and Unrestricted Exposure
^g/1
Micrograms Per Liter
l^g/kg
Micrograms Per Kilogram
|ig/m3
Micrograms Per Cubic Meter
VI
Vapor Intrusion
VIMS
Vapor Intrusion Mitigation System
VI SL
Vapor Intrusion Screening Level
VOC
Volatile Organic Compound
WTP
Water Treatment Plant
ZVI
Zero-Valent Iron
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This Record of Decision (ROD) documents the selected site-wide remedy for the Pike and
Mulberry Streets PCE Plume Superfund Site (P&M Site or Site) in Martinsville, Morgan County,
Indiana (the City). The ROD is organized in three sections: Part I contains the Declaration for the
ROD, Part II contains the Decision Summary and Part III contains the Responsiveness Summary.
Part I: Declaration
The Declaration summarizes the information presented in the ROD and includes the authorizing
signature of the Director of the Superfund & Emergency Management Division, United States
Environmental Protection Agency (EPA), Region 5.
Site Name and Location
Pike and Mulberry Streets PCE Plume Superfund Site
Martinsville, Morgan County, Indiana
National Superfund Identification Number: INN000508678
Statement of Basis and Purpose
This decision document presents the selected site-wide remedy for the P&M Site, which was
chosen in accordance with the Comprehensive Environmental Response, Compensation and
Liability Act (CERCLA) of 1980, as amended, 42 U.S.C. § 9601 et seq., and, to the extent
practicable, the National Oil and Hazardous Substances Contingency Plan (NCP), 40 C.F.R. Part
300. This decision is based on the Administrative Record (AR) file for this Site. The AR Index,
included as Appendix A, identifies each of the items comprising the AR upon which the
selection of the remedial action is based.
In a February 11, 2021 letter, the Indiana Department of Environmental Management (IDEM)
indicated that it concurs with the selected remedy in this ROD. This letter is included as
Appendix B.
Assessment of Site
The response action selected in this ROD is necessary to protect the public health or welfare or
the environment from actual or threatened releases of hazardous substances into the
environment.
Description of the Selected Remedy
This ROD sets forth the final site remedy for volatile organic compound (VOC) contamination in
groundwater and soil vapors at the Pike and Mulberry Site (see Figure 1, Site Location Map).
The selected remedy includes groundwater alternatives GW2 (Option GW2A) and GW5 and soil
vapor alternative SV5. This remedy will address potential exposure to VOCs in groundwater
exceeding drinking water standards by treating the contaminated groundwater at the Site, both in
the aquifer and from the City's water treatment plant (WTP) before the water is provided to
residents, and implementing institutional controls to prevent consumption of untreated water.
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This remedy will address potential exposure to unhealthy concentrations of soil vapors in indoor
air through a combination of treatment of the soil vapors, installation of systems to prevent the
soil vapors from entering occupied structures, and implementation of institutional controls.
Implementation of this remedy will continue as necessary to assure protection of human health
and the environment.
The selected Site remedy includes soil vapor source removal using soil vapor extraction (SVE).
EPA may also implement limited soil excavation to assist with soil vapor source removal if
appreciable amounts of Site-related soil contamination are identified during subsequent
investigations or other actions at the Site.
In summary, the selected Site remedy includes the following components:
• Groundwater Alternative GW-2A (Granular Activated Carbon) at the City's WTP;
• Groundwater Alternative GW-5 (In Situ Chemical Reduction) with a contingency to
implement Groundwater Alternative GW-6 (In Situ Chemical Oxidation);
• Soil Vapor Alternative SV-5 (Pathway Sealing, Vapor Intrusion Mitigation, and Soil
Vapor Source Removal); and
• Institutional Controls.
Statutory Determinations
The selected remedy is protective of human health and the environment, complies with federal
and state requirements that are applicable or relevant and appropriate to the remedial action, is
cost-effective, and utilizes permanent solutions and alternative treatment technologies to the
maximum extent practicable.
The Site remedy is consistent with the statutory mandate for permanence and treatment to the
maximum extent practicable. This selected remedy action does utilize groundwater treatment as
a principal element of the remedy that will permanently and significantly reduce the toxicity,
mobility, or volume of hazardous substances, pollutants, or contaminants.
The statutory preference for treatment of principal threat waste does not apply because there is
no known principal threat waste at the Site.
Until remedial action objectives are achieved, hazardous substances will remain at the Site in the
groundwater above levels that allow for UU/UE. As a result, statutory reviews will be conducted
every five years after commencement of the remedial action to ensure that the remedy is, or will
be, protective of human health and the environment until the RAOs are achieved.
ROD Data Certification Checklist
The following information is included in the Decision Summary section (Part II) of this ROD.
Additional information can be found in the AR file for the Site.
• Contaminants of concern (COCs) and their respective concentrations (Section 5.3);
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• Baseline risk represented by the COCs (Section 7.0);
• Cleanup levels established for COCs and the basis for the levels (Sections 7.1 and 8.0);
• Assumptions in the baseline risk assessment and the ROD (Sections 7.0);
• Current and reasonably anticipated future land use assumptions used in the baseline risk
assessment and ROD (Section 7.0);
• Potential land use that will be available as a result of the selected remedy (Section 6.0);
• Estimated capital, operation and maintenance (O&M), and total present worth costs;
discount rate; and the number of years over which the remedy cost estimates are
projected (Section 9.0); and
• Key factor(s) that led to selecting the remedy (Section 10.0).
Support Agency Acceptance
IDEM supports the selected remedy. EPA received a February 11, 2011, letter from the Assistant
Commissioner in the Office of Land Quality in IDEM expressing concurrence with the selected
remedy (see Appendix B).
Authorizing Signature
3/11/2021
X
Douglas Ballotti, Director
Superfund & Emergency Management Division
Signed by: DOUGLAS BALLOTTI
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Part II: Decision Summary
1.0 Site Name, Location and Description
Name: Pike and Mulberry Streets PCE Plume (P&M) Site
Location: Martinsville, Morgan County, Indiana
National Superfund Identification Number: INN000508678
Lead Agency: EPA
Support Agency: IDEM
The Site is primarily a tetrachloroethylene (PCE)1 groundwater plume that is centered near the
intersection of Pike and Mulberry Streets in Martinsville. The groundwater plume extends
downgradient to the northwest to the City's municipal wellfield and upgradient to the southeast
just beyond the intersection of Jackson and Sycamore Streets, with a lobe extending to the west
past the intersection of Morgan Street and Shirley Drive. (See Figure 2).
The Site also includes soil vapor contamination resulting from contaminants volatilizing from
soil and groundwater. Figures 3 and 4 depict the area of soil vapor contamination, which is
similar in aerial extent to the shallow groundwater contaminant plume with a few exceptions.
One notable exception is an area of soil vapor contamination that extends to the east on
Washington Street outside of the groundwater plume area. This area of soil vapor contamination
may be intersecting with another area of contamination being investigated by IDEM (O'Neal's
Cleaning Depot).
The contaminants of concern (COC) at the Site2, which are CERCLA hazardous substances,
consist of PCE in groundwater and PCE and trichloroethene (TCE) in soil vapor.
2.0 Site History and Enforcement Actions
2.1 Site History
The initially identified source of PCE contamination at the Site is the former Master Wear
facility (the Facility), which is located on the west side of the courthouse square in downtown
Martinsville. The Facility was constructed in 1956 and operated as a furniture store until 1985.
Master Wear, Inc. (Master Wear), also known as American Glove, operated in the Facility from
January 1986 to November 1991. Master Wear was an industrial dry cleaner that used PCE to
perform laundering and dry cleaning for commercial and institutional organizations. Between
1987 and 1991, multiple complaints of illegal dumping and mishandling of waste drums at the
Facility were reported to IDEM. Several spills and releases were also reported. The warehouse
portion of the Facility was vacated in 1991, but since then, miscellaneous household items have
been stored there. The western portion of the Facility periodically housed miscellaneous shops,
1 Other synonyms for tetrachloroethylene include "perchloroethylene" or"perc."
2 PCE and TCE are currently the only COCs; however, EPA may address additional related COCs (including PCE
and TCE degradation products) during the implementation of the remedial action.
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such as a hair-styling business, an antiques shop, a curios shop, a manicure service, and an
insurance office.
In August of 1992, IDEM removed drums from the Facility and oversaw investigations at or near
the Facility between 1996 and 1999.
In November 2002, the PCE concentration in City well PW-1, downgradient from the Facility,
exceeded the federal Safe Drinking Water Act (SDWA) maximum contaminant level (MCL) of 5
micrograms per liter (|ig/L). The IDEM Office of Water Quality ordered the well temporarily
closed, and the City diverted its drinking water supply to the other two wells in the municipal
wellfield until it implemented granular activated carbon (GAC) treatment of the drinking water
supply in 2005.
The IDEM Site Investigation Program began investigating the presence of PCE in the municipal
wellfield in late 2002. The Facility was entered into the Comprehensive Environmental
Response, Compensation, and Liability Information System database in January 2003. IDEM
staff conducted a preliminary assessment (PA)/site inspection (SI) in 2003 and 2004 in four
phases. In the first phase, IDEM confirmed the presence of PCE in Municipal Well #3 (at a
concentration of 4.2 (J,g/L) and identified Master Wear, Inc. as a possible PCE source. However,
contamination also was found in samples that were cross-gradient to the former Master Wear
facility. The second phase of the PA/SI involved the use of a direct-push technology (DPT) rig to
collect soil and groundwater samples at and near the former Master Wear facility. IDEM
detected PCE in subsurface soil at levels as high as 270 milligrams per kilogram (mg/kg) and in
groundwater as high as 20,000 [j,g/L at the former Master Wear facility. In the third phase, IDEM
collected indoor air samples and confirmed the presence of indoor air contamination at various
businesses and residences in the immediate vicinity of the groundwater plume. In the fourth
phase, IDEM advanced an additional 14 borings using a DPT rig to collect groundwater samples.
At this time, IDEM referred the matter to EPA's Superfund Removal Program.
2.2 Removal Action
A time-critical removal action (TCRA), overseen by EPA, was conducted from 2005 through
2008 at the Facility. The TCRA was implemented by Master Wear under an Administrative
Order issued by EPA. The action was conducted to address PCE contamination in soil,
groundwater, and indoor air on or near the Facility property. The treatment of the identified
source area included installing a combination air sparging (AS) and soil vapor extraction (SVE)
system over a limited area of the source zone, including the parking lot just north of the Facility
and along portions of Mulberry Street up to Morgan Street. The SVE/AS system, along with
individual sub-slab depressurization (SSD) vapor intrusion (VI) mitigation systems (VIMS) and
passive venting in nearby structures, began operation on January 7, 2005 to address VI. The
TCRA did not include removal of impacted soils except from piping trenches and SVE/AS well
locations when the remedial system was installed.
The SVE/AS system operated until November 9, 2006, when the closure criteria were met, and
the system was shut down. Two pre-closure assessments (PCAs) were conducted in 2006 (one in
April and one in November) to evaluate the efficiency of the system at addressing soil and soil
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vapor contamination near the Facility. Ten direct-push borings were advanced during the first
PC A adjacent to soil borings demonstrating the highest PCE concentrations in soil during
previous investigations, and an additional five borings were advanced during the November
PCA.
Figure 5 provides the soil sampling results from the PCAs for the Master Wear removal action.
It shows a comparison of PCE concentrations in subsurface soil from the original investigations
to the PCE concentrations from the PCAs. The borings advanced during the April PCA are
denoted with an "A" suffix after the original boring name, and the borings advanced during the
November PCA are denoted with a "B" suffix. The PCE concentrations that exceeded IDEM's
targeted soil clean-up level (640 micrograms per kilogram or |ig/kg) are shown in red, and PCE
concentrations less than IDEM's targeted clean-up level are shown in blue. PCE concentrations
in soil samples collected from the April PCA range from 16 to 1,600 |ig/kg, and PCE
concentrations in soil samples collected from the November PCA range from below the
quantitation limit to 750 |ig/kg at soil boring location SB-4B, which was the only remaining soil
boring location after the November PCA with a PCE concentration in soil exceeding the IDEM's
targeted clean-up level. This sample was collected from the 18- to 20-foot depth interval and the
boring was located within the Facility parking lot towards the northwest corner of the building,
approximately 30 feet to the northwest of the MW-1 well cluster and 15 feet southeast of the
SVE-1 extraction well. Although the system included one SVE well and two air sparge wells
beneath the building at the Facility, the PCAs did not include results for soil samples from
beneath this building nor did it assess the effectiveness of the SVE/AS under this building.
The SVE/AS system was restarted in August 2007 after indoor air samples from two of three
spaces sampled within the Facility exceeded the sub-chronic action levels. The system was
turned off again on March 31, 2008, at which time indoor air, soil, and groundwater sample
results indicated that the closure criteria had been met. The SVE/AS system and individual SSD
systems were later removed. Analyses of soil and groundwater samples collected after the
TCRA, to evaluate the performance of the SVE/AS system, detected residual levels of PCE but
all sample points were below IDEM's targeted clean-up level.
2.3 Post-removal Investigation
After completion of removal activities, groundwater in and around the facility was monitored.
Also, the City continued to monitor PCE in groundwater from its municipal wellfield and has
continued to operate its GAC unit to comply with the MCL for PCE.
After IDEM had obtained sufficient data to determine that a groundwater plume remained that
would continue to threaten the municipal wellfield for some time and that the Facility was not
likely the only source of groundwater contamination in the area, IDEM requested that EPA
assess the Site to determine its eligibility for the Superfund National Priorities List.
EPA added the Pike and Mulberry Streets PCE Plume Site to the NPL in May 2013. The Site is
so named as preliminary investigation data indicated that this intersection was in the
approximate center of the plume and is not named "Master Wear" because preliminary data
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included elevated concentrations of groundwater contamination upgradient of the Master Wear
facility, indicating other contributing sources to the groundwater contamination.
2.4 Remedial Investigation Activities
After the Site was listed on the NPL, EPA initiated an investigation to identify potential
historical sources and associated responsible parties (potentially responsible parties or PRPs)
capable of leading the remedial investigation (RI). EPA was unable to identify any liable and
viable PRPs to conduct the RI so it initiated a federally-funded RI in 2014. The RI included
seven sampling phases conducted from April 2015 through January 2017. The RI activities, data
collection methodologies, resulting data, physical characteristics of the Site, nature and extent of
contamination, contaminant fate and transport, and conceptual site model (CSM) are
documented in detail in the RI Report.
A human health risk assessment (HHRA) and a screening-level ecological risk assessment
(SLERA) were also completed as part of the RI. The HHRA is presented as Appendix M in the
RI and the SLERA is presented as Appendix O in the RI report.
2.5 Concurrent Investigations
A third-party VI investigation was performed in August 2015 for three noncontiguous buildings
located within the footprint of the PCE groundwater plume. The findings of this investigation
indicated the presence of VOCs within and underneath these three buildings.
Additional VI sampling was conducted by EPA's Superfund Technical Assessment and
Response Team in January 2016, after the preliminary findings of the first four phases of the RI
were evaluated. Nine residential properties were sampled based on the Agency for Toxic
Substances and Disease Registry (ATSDR) recommendation and proximity to the PCE
groundwater plume.3
IDEM is also conducting investigative and cleanup activities for PCE, including VI, related to
O'Neal's Clothes Depot (currently Vista Cleaners), which is located approximately 0.5 mile to
the east of the Facility (see Figures 3 and 4).
3.0 Community Participation
EPA conducted community interviews in 2015 and in 2019 to better understand the community
and its needs regarding the Site. These interviews were conducted with residents and business
owners in the community as well as local and county officials. EPA completed a community
involvement plan for the Site in August 2019 (https://semspub.epa.gov/work/05/'H'H i |M£).
3 EPA conducted its more extensive VI investigation as part of Phases 6 and 7 of the RI after reviewing this initial
investigation and receiving a recommendation to do so by ATSDR.
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4.0 Scope and Role of Operable Unit
This site-wide remedy addresses all the contaminant areas of concern for the P&M Site in one
operable unit. The selected remedy will address treatment of contaminated groundwater at the
Site; continued treatment of the City's drinking water at the WTP to remove Site contaminants;
connecting to municipal water any residential properties with wells located in the groundwater
contaminant plume; removal of soil vapor sources; VI monitoring and, if necessary, mitigation;
and placement of institutional controls (ICs) on affected land and groundwater to prevent
exposures until Site clean-up goals are met.
5.0 Site Characteristics
5.1 Physical Characteristics
The Site is in Martinsville, Indiana, which is located in south central Indiana and is
approximately 30 miles southwest of Indianapolis, Indiana. Martinsville is surrounded by
unincorporated areas of Morgan County, and the nearby towns include Paragon (6.5 miles to the
west) and Morgantown (9.4 miles to the southeast). The major routes through Martinsville are
State Routes 37, 44, and 252. The north-to-south-flowing White River is located 1.5 miles to the
west/northwest of Martinsville.
During the RI, EPA did not identify any subsurface features in the area (natural or manmade)
other than City of Martinsville water, storm, and sanitary sewer lines and private company
utilities. However, after RI activities were completed, EPA was made aware of possible
subsurface structures such as a tunnel underneath or in the vicinity of the Facility. If found
during pre-design investigations, subsurface structures in this area may have some relevancy in
the design of the remedial action for soil vapor.
5.1.1 Climate
The climate of Morgan County is humid and temperate, with warm, humid summers and
moderately cold winters. According to the National Oceanic and Atmospheric Administration,
average daily temperatures for Morgan County ranges from 72.1 degrees Fahrenheit (°F) in the
summer to 29.5 °F in the winter. For the period of record (1971-2000), annual average
precipitation is approximately 43.1 inches, ranging from 40 inches in the northern part of the
basin to 48 inches in the south-central part of the basin, and usually is distributed evenly
throughout the year. Rainfall in the winter and early spring is generally of long duration, steady,
and of mild intensity, whereas late spring and summer rainfall tends to be of short duration and
high intensity.
5.1.2 Topography
Martinsville is approximately 607 feet above mean sea level. The Site is located in the Norman
Upland physiographic unit of the White River Basin in south-central Indiana. The Norman
Upland is characterized by narrow, flat-topped divides and deep V-shaped valleys. Local relief is
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typically 125 to 250 feet. The Norman Upland is well-drained by a strongly dendritic stream
pattern.
5.1.3 Regional Soils
The predominant surficial soil types mapped for the Site and surrounding area are dominated by
Martinsville loam, Princeton fine sandy loam, Rensselaer clay loam, and Whitaker loam. These
account for approximately 92 percent of the surficial soil types within the City of Martinsville.
The Martinsville loam occurs in outwash plains and terraces and is well-drained and moderately
permeable. Surface soil to a depth of about 8 inches is usually a brown to grayish brown, very
friable, dry fine sandy loam. The subsurface to 43 inches is typically a firm, brown to dark
yellowish-brown clay to sandy clay loam.
The Princeton fine sandy loam consists of well-drained soils that are typically formed on dunes
and less commonly, on stream terraces. Slope variation can range from 2 to 25 percent. Surface
characteristics are brown to grayish brown, very friable, dry fine sandy loam to a depth of 8
inches. Subsurface layering consists of brown to yellowish red sandy or sandy clay loam or
loamy sand that is friable and approximately 52 inches thick.
Rensselaer clay loam occurs within the depressions on outwash plains and is poorly drained.
Slope variation can range from 0 to 2 percent. Surficial material, to a depth of 11 inches, is
typically a gray to very dark gray, friable, dry clay loam. Material underlying the above layer, to
a depth of 60 inches, is gray to dark gray, friable to firm, clay or silt loam.
Whitaker loam consists of very deep, somewhat poorly drained soils formed in stratified silty
and loamy outwash on outwash, lake, or till plains. Slope variation can range from 0 to 6 percent.
The soil is generally dark grayish brown to light brownish gray, dry, friable loam to a depth of 9
inches. Subsurface soil is typically brown to grayish brown, friable to firm, clay or sandy clay
loam down to 39 inches.
5.1.4 Regional Geology
The City of Martinsville is located in a glacial outwash (sands and gravel) area, ranging from
less than 50 to over 150 feet thick, of Wisconsinan, Illinoian, and pre-Illinoian glaciation events
and overlies bedrock composed of mainly siltstones and shales (with minor sandstone and
limestone) of the Mississippian-age Borden Group. A topsoil layer less than 10 feet thick
overlies the glacial deposits in the study area. The Borden Group ranges from 485 to 800 feet
thick.
5.1.5 Regional Surface Water Hydrology
Surface water hydrology is dominated by the West Fork of the White River, located
approximately 1.17 miles from the Master Wear facility. The White River Basin is part of the
Mississippi River system and drains 11,350 square miles of central and southern Indiana. Long-
term average streamflow is about 12,300 cubic feet per second near the White River's
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confluence with the Wabash River in southwestern Indiana. Variations in streamflow are
generally moderate and seasonal. Streamflow is typically highest in April and May and lowest in
late summer and fall. There is a levee northwest of the City to control the flow of the West Fork
of the White River.
5.1.6 Regional Hydrogeology and Groundwater Use
The regional aquifer is in the fluvial and glaciofluvial (glacial outwash) sand and gravel unit
found near the surface to the bedrock along the floodplain of the White River. Although not
necessarily a continuous, single geologic deposit, these unconsolidated sands and gravels are a
single stratigraphic unit with hydraulic connectivity throughout. Hydraulic conductivities for
sand and gravel aquifers within the White River Basin, similar to the one in this study area, range
from 24 to 1,500 feet per day and produce well yields from 10 to 2,000 gallons per minute. The
City of Martinsville's municipal wells use groundwater from the unconsolidated sand and gravel
aquifer located within this unit.
Bedrock aquifers are developed in an upper weathered zone of the Mississippian Borden group.
The upper weathered zone is a zone of enhanced permeability produced by weathering before,
during, and after glaciation. The availability of water in this weathered zone is highly variable
and is dependent on the degree of enhanced permeability, the type and thickness of overlying
deposits, and the bedrock topography. The shale siltstone upper weathered bedrock aquifer is
used primarily for domestic and stock water supplies in areas where no other aquifers are
available.
5.1.7 Site Geology
Generally, the geology at the Site consists of approximately 5 to 8 inches of topsoil (when
present) composed of silt or clay with variable amounts of sand. Topsoil thicknesses of 9 to 12
inches are present in a few locations. Locations without topsoil are usually paved with fine sand
below asphalt/concrete and gravel. Below topsoil and pavement with fine sand is predominately
fine to medium, coarse to rounded gravel and fine to coarse sand with no to some silt and clay.
The underlying bedrock is encountered at between approximately 53 to 98.5 feet below ground
surface (bgs), with the bedrock's high elevation being located toward the middle of the Site (near
monitoring wells MW-01, MW-02, MW-16, and MW-07). No local or regional fine-grained
layers appear to be present beneath the Site based on review of previously installed boring logs
and geologic material observed during the RI.
5.1.8 Site Surface Water Hydrogeology
Since the Site is located in urban commercial and residential areas, the surface drainage pattern
has been altered by roadway, driveway, and building construction. Surface water runoff from
buildings, developments, and streets is directed into the City of Martinsville stormwater sewer
system. A local topographic high is located to the northeast of the Site, designated on
topographic maps as Lincoln Hill, with a maximum elevation of approximately 830 feet above
mean sea level.
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5.1.9 Site Hydrogeology
The groundwater contamination at the Site is in the surficial aquifer. During the RI, EPA found
the depth to groundwater to range from 5 to 17 ft bgs. For purposes of investigation, EPA
divided this aquifer into shallow (17-27 ft bgs), intermediate (43-60 ft bgs), and top of bedrock
(67-99 ft bgs) water-bearing zones. Based on data gathered during the RI and historical data,
EPA found that groundwater elevation in each zone of the aquifer was highest in the southeast
corner of the Site and lowest in the northwest corner and groundwater migrates to the northwest,
towards the municipal supply wells. The northwest migration pattern is likely influenced by the
municipal supply wells. A more western or southwestern groundwater migration pattern toward
the White River to the west would be expected without the hydraulic influence of the municipal
supply wells. EPA observed seasonal variations in water levels between the spring, summer, and
fall. Water levels were on average approximately 4 feet higher in the summer than the fall and
approximately 2 to 3 feet higher in the summer than the spring; however, EPA observed that the
gradients are consistently in a southeast to northwest direction with groundwater flow.
During the RI, EPA also determined that the hydraulic conductivity of the aquifer ranged from
1.2 x 10"3 to 4.1 x 10"2 centimeters per second (cm/s) in the shallow zone of the aquifer, 9.0 x 10"
4 to 3.6 x 10"2 cm/s in the intermediate zone of the aquifer, and 3.7 x 10"2 to 4.2 x 10"2 cm/s in the
top of bedrock zone of the aquifer. EPA calculated the average groundwater velocities ranging
from 34.4 feet per year (ft/yr) to 89.3 ft/yr in the shallow zone, 137 ft/yr to 233 ft/yr in the
intermediate zone, and 605 ft/yr to 982 ft/yr in the top of bedrock zone. Although the vertical
gradients showed some variability between each phase of the groundwater investigation, the
average gradients were typically downward (from shallow to intermediate or to deep portions of
the aquifer) and relatively low (less than 0.001 foot per foot). The low vertical gradients indicate
that the groundwater flow is predominantly in the horizontal direction. However, EPA observed
anomalously high and upward vertical gradients in the MW-4 well nest, likely due to the bedrock
high that is directly downgradient of the nest.
5.2 Nature and Extent of Contamination
EPA determined the nature and extent of Site contamination during the RI, and it conducted the
RI between April 2015 and February 2017 using a phased approach. The significant findings and
conclusions from the site characterization activities completed during the RI are summarized
below. The April 2018 Final RI Report provides additional detail about site investigations and
can be found at: (https://semspub.epa.gov/src/document/05/941790).
5.2.1 Groundwater
The only groundwater contaminant that EPA identified above its screening level (SL) is PCE.
The SL for PCE is the SDWA MCL of 5 |ig/l. The highest PCE detection that EPA found during
the RI (240 |ig/l) is in a monitoring well (MW-1S) located near the Facility. EPA identified PCE
degradation products, including TCE and cis-l,2-dichloroethylene (cis-l,2-DCE), in
groundwater but not above their respective SLs (MCLs of 5 |ig/l and 70 |ig/l, respectively). The
groundwater plume is well-defined horizontally and vertically and is limited to the upper,
surficial aquifer. The groundwater plume consists of two "lobes" radiating from the Facility. A
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third "lobe" extends towards the Facility from a potential upgradient source. The plume is most
extensive in the shallow zone of this aquifer with some contamination extending to the
intermediate depth. At the municipal wellfield, the plume is drawn into the lower portion of the
aquifer by the pumping action of the production wells. The concentrations are highest in the
center of the plume near the Facility with lower concentrations on the periphery, including the
portion of the plume that is being drawn into the municipal wells.
5.2.2 Soil
EPA performed soil sampling at 66 locations and found a single exceedance of the residential,
risk-based SLs. Specifically, EPA detected TCE at 3,600 micrograms per kilogram (|ig/kg) in a
single, shallow soil sample from just north of the Facility. The residential SL for TCE is 410
|ig/kg. Although EPA identified PCE in 27 of the 66 soil samples, all detections were below the
residential SL of 8,100 |ig/kg.
The extent of impacted soils appears to be limited to the area immediately adjacent to the Facility
and the uppermost soil interval. This is likely due to the efforts of the previous removal action
EPA oversaw at that Facility that treated the soils using SVE/AS. EPA notes that there may be
impacted soils under the building at the former Master Wear facility and that these soils have not
been sampled. Additional investigation of this area may be required during design or at a later
time when these soils become more accessible (e.g. during or after future construction and/or
demolition work at the building).
5.2.3 Soil Vapor
Figures 3 and 4 are maps presenting the PCE and TCE, respectively, in soil vapor data collected
during the RI.
EPA conducted soil vapor sampling over four phases. In the first two phases, EPA sampled soil
vapor in 18 and 174 soil vapor points (SVPs) located above the center (highest concentration
area) of the groundwater plume. In the third and fourth phases, EPA conducted an expanded soil
vapor investigation using 77 (third phase) and 52 (fourth phase) temporary soil vapor probes and
an instrument that analyzes samples and provides results in real time. EPA arranged the
temporary SVPs around the circumference of the initial (first and second phase) soil vapor
exceedances and installed additional SVPs in expanding concentric circles to delineate the extent
of the soil vapor plume. EPA then compared these results of the analyses of these soil vapor
samples to its most protective risk-based residential SL for soil vapors below the slab (sub-slab)
of a home or other dwelling.
During each of the first and second phases of its soil vapor investigation, EPA identified 15 PCE
exceedances and 3 TCE exceedances of EPA's risk-based, residential sub-slab VI screening
levels (VISLs), 360 micrograms per cubic meter (|ig/m3) for PCE and 16 |ig/m3 for TCE. In both
phases, EPA found the highest concentrations of PCE and TCE in soil vapor (180,000 |ig/m3 and
16,000 |ig/m3, respectively) in a soil vapor well (SG-1) located just north of the Facility5. EPA
4 During the second phase of soil vapor sampling, one of the SVPs did not pass a leak test and was not re-sampled.
5 EPA notes that this soil vapor well is in close proximity to the single soil sample exceedance.
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also found particularly elevated soil vapor concentrations at several other SVPs in the vicinity of
SG-1.
In the third and fourth phases, EPA identified 40 additional PCE exceedances and 11 additional
TCE exceedances of EPA's risk-based, residential sub-slab VISLs, as well as two additional
areas with notably elevated soil vapor concentrations, though none were similar in magnitude to
the concentrations detected in the vicinity of SG-1. One of these additional areas is located to the
southeast of the Facility, in the vicinity of the intersection of Jackson and Sycamore Streets. The
other is located to the northwest of the Facility, in the vicinity of the intersection of Harrison and
Cherry Streets.
EPA was able to use the data from the four phases of soil vapor sampling to nearly fully
delineate the extent of the soil vapor plume above the most conservative risk-based residential
SLs for sub-slab vapors, with one notable exception. EPA was not able to delineate the eastern
extent of the soil vapor plume on Washington Street. EPA believes that soil vapor from the Site
plume in this area may comingle with soil vapors from an adjacent site with PCE contamination
in groundwater that IDEM is overseeing, O'Neal's Dry Cleaners. The scope of the O'Neal's Dry
Cleaners investigation has included VI investigation.
5.3 Conceptual Site Model
EPA developed the CSM by integrating technical information from a variety of sources,
including the physical characteristics, the nature and extent of contamination, and contaminant
fate and transport pathways. Figure 6 presents the CSM of PCE in groundwater and soil vapor,
Figure 7 presents the CSM of TCE in soil vapor, and Figure 8 presents the CSM of COCs in soil.
Although TCRA clean-up activities were implemented to address the potential source area at the
former Master Wear facility, some residual source contamination may exist at or near the
Facility. Soil exceeds its SL for TCE in one surface sample collected near the former Master
Wear facility. No soil samples were taken from below the building at the Facility. The sources of
potential contamination at the Site are likely historical discharges of waste material and solvents
from the former Master Wear facility and possibly other sources, as discussed in the RI report.
Recent sampling indicates that PCE concentrations in groundwater downgradient (and
upgradient) of the Facility exceed the MCL. Soil vapor exceeds the PCE and TCE SLs at
multiple locations upgradient and downgradient of the Facility.
COCs could have been released to the environment as dissolved-phase constituents in water or as
free-phase product (nonaqueous phase liquid or NAPL)6. Dissolved-phase COCs would migrate
downward and be subject to soil sorption and volatilization. Likewise, free-phase NAPL would
migrate downward and be subject to soil sorption and volatilization, as well as dissolution into
soil moisture and retention of discontinuous droplets in soil pores. Precipitation and infiltration
will continue to leach sorbed-phase COCs (and trapped NAPL, if any) downward to the saturated
zone over time, constituting a continuing source of contaminants to groundwater.
6 Note that EPA did not identify any NAPL at the Site.
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Based on previous investigations conducted at the Site and the data gathered during the RI, EPA
determined that the vadose zone is not currently a continuing source of groundwater
contamination sitewide. However, EPA determined that vadose zone contamination may be an
ongoing source of soil vapor contamination, particularly at soil sample point SG-01 (near the
former Master Wear facility). EPA identified an exceedance of TCE in surface soil (1 to 2 feet
bgs) at this location and detected PCE and TCE in shallow soils in the multiple other locations
within this vicinity (though below SLs). An AS/SVE system was operated in this area as part of
the Master Wear removal action, and it achieved the treatment objectives and substantially
reduced VOC concentrations in soil. EPA believes that residual PCE and TCE may still be
present in vadose zone soil in this area.
PCE, the primary groundwater COC, is not expected to adsorb to the sandy matrix present
beneath the Site. For this reason, the plume is expected to continue to migrate with the
groundwater flow, primarily by advection and dispersion. Groundwater flow in the shallow,
intermediate, and top of bedrock water-bearing zones of the aquifer is to the northwest, towards
the municipal supply wells, and is likely influenced by the pumping rates of the municipal supply
wells. A more western or southwestern groundwater flow direction toward the White River to the
west would be expected without the hydraulic influence of the municipal supply wells.
PCE and TCE are the principal contaminants within soil vapor at the Site. These and other VOCs
located in subsurface soils or in groundwater can volatilize, migrate through soil as vapor, and
transport into and accumulate in indoor spaces, where inhalation exposures can occur. Generally,
EPA observed PCE and TCE vapors in soil to follow exceedances in groundwater and along
preferential pathways (e.g., utility corridors).
Based on soil vapor concentrations detected during Phases 2 through 5, three areas were
identified where PCE soil vapor concentrations are greater than 15,000 (J,g/m3, as shown in
Figure 3. The first high PCE soil vapor concentration area is located around the former Master
Wear facility and the former Manitorium Cleaners. Contamination released from these facilities
may be acting as potential soil vapor sources. The second high PCE soil vapor concentration area
is located within the northwest portion of the study area approximately 1,200 feet downgradient
of the former Master Wear facility. However, this area is not located near an identified potential
past PCE user nor are there high concentrations of PCE in groundwater in this area. There may
be an unidentified source of PCE in soil vapor in this area, or PCE may be migrating to this area
through preferential pathways from another source area. Preferential pathways, such as the
sanitary line, storm line, or other utility conduits, may transport VOC vapors between a potential
source and building over greater distances than what is typically observed due to vadose zone
diffusion and advection. The third high PCE soil vapor concentration area is located to the
southeast (and upgradient) of the former Master Wear facility and just to the west of the former
Central Dry Cleaners. Contamination released from this facility may be acting as a source of the
soil vapor in this area.
EPA also observed elevated PCE concentrations in soil vapor samples to the east of the Site
along Washington Street. EPA did not identify any past potential PCE users in this area and
believes that these contaminants could have potentially migrated along a utility corridor. In
particular, the pipe bedding for the water main that runs along Washington Street could
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potentially serve as a preferential pathway for vapor migration. Sanitary and/or storm lines may
also be present along portions of Washington Street and serve as soil vapor conduits. In addition,
PCE in soil vapor from the potential source at the O'Neal's Clothing Depot site may also be
migrating from the east along the utility corridor.
EPA only identified three locations with TCE concentrations in soil vapor exceeding the SL (16
(j,g/m3), and each is generally located near identified potential past PCE users, as shown in
Figure 4. The TCE result from one of these locations, near the former Master Wear facility, was
160,000 [j,g/m3.
Soil vapor can migrate across a building slab and/or basement or foundation walls through two
mechanisms: (1) advection through cracks, seams, or other openings, and (2) diffusion directly
through the concrete, brick, or concrete blocks. Advection across the slab has been the
predominant mechanism discussed in the literature and guidance. Building characteristics such as
age, condition, construction type, heating, venting, and air conditioning (HVAC) type, and the
presence of preferential pathways can also influence the VI pathway. Advection can be affected
by barometric pressure changes, wind load, thermal currents, depressurization caused by HVAC
systems, exhaust fans, or the stack effect, which is caused by the difference in pressure between
the less-dense interior heated air and denser cold outdoor air. This pressure differential can result
in infiltration of air and soil vapor into the lower part of the building. The gas permeability of the
slab affects the rate at which vapor enters a structure.
Building slabs at the properties where VI assessments were conducted were in varying degrees of
condition ranging from good with no observed cracks, to significant cracking or even missing
sections with exposed dirt. These observed openings can generally be presumed to be routes for
potential VI.
Once VOCs have entered the indoor air of a building, concentrations can be attenuated through a
number of dilution processes, including both natural and mechanical building ventilation and
adsorption to building materials. The building envelope leakage (walls and roof) and the
mechanical ventilation rate affect the dilution of VOCs that have entered the building.
VOCs do not persist in indoor air without an ongoing source, as typical residential air exchange
rates are on the order of 0.25 air exchanges per hour. If the source is discontinued, concentrations
rapidly decrease within a few days. In addition, VOCs are subject to sorption and desorption
processes from building materials. Therefore, observed persistence in indoor air is evidence for
the presence of an ongoing source, which can be either ongoing VI or a product containing
VOCs in use or stored within the structure.
At this site, the presence and operation of a heating system within a building appears to be a
major consideration for VI due to the stack effect. There does not seem to be a strong geographic
pattern between VI results and property location; however, there are multiple properties where
access was not granted for VI sampling, so EPA is basing this observation on limited data.
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6.0 Current and Potential Future Land Use
Martinsville is the county seat of Morgan County, and the town's residential population is
approximately 11,800 people (2010 Census), with 5,100 housing units. In the RI, EPA estimated
that up to 4,748 people live within Vi mile of the Site.
Figure 9 presents Site features and land use for the Site. The buildings that overlay the Site are a
mix of residential, commercial, and industrial uses. The economy of the area consists of
agricultural and industrial concerns. The latter includes brick manufacturing, manufacturing of
aircraft and missile components, and several large-scale goldfish hatcheries. Martinsville is
surrounded by rural farmland, and the City is a suburban setting with a town square.
EPA expects that the future use of land at the Site will not change significantly. However, the
state highway that runs through the town is being converted into an interstate connecting
Evansville, Indiana with Indianapolis, Indiana. Representatives from the City of Martinsville
informed EPA that it expects additional development as a result.
Martinsville operates its only municipal wellfield in the northwest terminus of the groundwater
plume and draws its water from the surficial aquifer where the Site plume is located. The City
currently treats the groundwater with GAC before providing the water to its customers, and it is
in the process of replacing these wells with new wells in the same location from the same
aquifer. The only change to groundwater usage that EPA expects is a potential increase in
pumping rate if the City's population and/or municipal water customers grow.
7.0 Summary of Site Risks
EPA used data from the RI to conduct a baseline HHRA (BHHRA) and a SLERA. To conduct
these risk assessments, EPA assumed that the current land use at the Site will remain the same in
the future, which consists of mostly residential and small commercial operations but also
includes some government buildings and light industry. EPA also assumed that properties at the
Site will continue to have access to municipal water, while recognizing some properties in the
vicinity of the Site have private wells. EPA issued both of these risk assessments in April 2018
as appendices to the RI report.
7.1 Human Health Risk
EPA performed a BHHRA to assess risks posed by the Site in the absence of any future remedial
or other clean-up actions. Because this ROD addresses only groundwater and soil vapor
contamination, this section is limited to the risks posed by VI and exposure to contaminated
groundwater.
To evaluate the potentially complete exposure pathways further, EPA estimated and quantified
the magnitude, frequency, and duration of exposures as well as the concentrations of the
contaminants at the point of exposure. In the BHHRA, EPA followed its guidance in using
upper-bound parameter values (as opposed to average values) for exposure frequency and
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exposure duration. EPA also followed its guidance in selecting intake variable values for a given
pathway such that the combination of values from all variables results in a reasonable estimate of
the maximum exposure for each exposure pathway.
7.1.1 Contaminants of Concern
In the BHHRA, EPA evaluated the potential COCs in both groundwater and soil vapor. In
groundwater, EPA determined PCE and TCE in groundwater as posing potential risks but only
detected PCE above its MCL. In soil vapor, EPA determined that both PCE and TCE posed
potential risks via the VI pathway and identified both of these contaminants above their
respective soil vapor SLs. Therefore, EPA identified PCE as a COC for groundwater and both
PCE and TCE as COCs for soil vapor.
7.1.2 Groundwater
The BHHRA presents the potential current and future risks to human health posed by exposure
to contaminated groundwater via ingestion, inhalation, or dermal contact (described as "potable
use" in the BHHRA report) for both residents and commercial or industrial workers. EPA
evaluated the potential potable use of untreated, contaminated groundwater for the purposes of
the BHHRA. These exposure scenarios are only theoretical as the groundwater from the City's
municipal wells is being effectively treated using activated carbon, and EPA did not identify any
private, residential wells with contamination above SLs. However, it is possible that residential
wells exist (or could be installed) within the Site groundwater contaminant plume.
In the BHHRA, EPA also evaluated the potential exposure of construction workers to
contaminated groundwater via dermal contact or inhalation of contaminant vapors. For this
exposure scenario, EPA evaluated potential exposure from construction activities involving
digging to shallow groundwater contamination using data from monitoring wells screened at 10
ft bgs or less.
Based on monitoring well and municipal wellfield (pre-treatment) data gathered during the RI,
EPA found that the range of concentrations of Site contaminants in groundwater do not present
an unacceptable cancer risk to adult or child residents but may pose an unacceptable non-cancer
risk to residents. Specifically, EPA determined that the highest concentrations of Site
contaminants in groundwater increase a resident's excess lifetime risk of cancer (ELCR) by 2 in
100,000 (2 x 10"5), which is less risk that EPA's maximum acceptable ELCR of 1 x 10"4.
However, EPA did determine that the Site contaminants in groundwater pose an unacceptable
potential non-cancer health risk to adult and child residents, with a measured hazard index (HI)
as high as 3. EPA considers an HI of greater than 1 an unacceptable risk.
In the BHHRA, EPA determined that groundwater contaminants at the Site do not pose an
unacceptable cancer or non-cancer health risk to industrial, commercial, or construction workers
(non-potable uses).
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7.1.3 Soil Vapor
In the BHHRA, EPA considered current and future potential soil vapor exposure scenarios to
residents, industrial/commercial workers, and construction workers. For each of these receptor
groups, EPA considered exposure scenarios involving inhalation of indoor air after soil vapor
contaminants from the Site had accumulated within a structure. For the construction worker
scenario, EPA evaluated exposure to soil vapor from the Site released to the ambient air during
digging activities.
Based on sampling data gathered during the RI, EPA found that the range of indoor air
concentrations of Site contaminants do not present an unacceptable cancer risk to adult or child
residents but may pose an unacceptable non-cancer risk to these residents. Specifically, EPA
determined that the highest indoor air concentration of Site contaminants measured in residential
properties at the Site have the potential to increase a resident's ELCR by 2 in 100,000 (2 x 10"5),
which is less risk than EPA's acceptable maximum ELCR of 1 in 10,000 (1 x 10"4). However,
EPA also determined that the indoor air concentrations of Site contaminants pose unacceptable
potential non-cancer risks at two of the 50 properties sampled, with a measured HI as high as 6.
Based on sampling data gathered during the RI, EPA found that the range of indoor air
concentrations of Site contaminants do not present an unacceptable cancer risk to
industrial/commercial workers but may pose an unacceptable non-cancer risk to these workers.
Specifically, EPA determined that the highest indoor air concentration of Site contaminants
measured in commercial properties at the Site have the potential to increase a worker's excess
lifetime cancer risk (ELCR) by 8 in one million (8 x 10"6), which is less risk than EPA's
acceptable maximum ELCR of 1 in 10,000 (1 x 10"4). However, EPA also determined that the
indoor air concentration of one Site contaminant (TCE) at one of the 50 sampled properties poses
an unacceptable potential non-cancer risk to workers (i.e. an HI of greater than 1).
EPA notes that it was only able to sample 50 of the more than 200 occupied structures within the
soil vapor plume and that it is unclear how many additional properties may have unacceptable
risks from Site-related exposures to COCs via the VI pathway. EPA will attempt to obtain access
to sample more of these properties during subsequent VI investigations.
7.2 Ecological Risk
EPA conducted a SLERA and determined that Site contaminants do not pose actual or potential
unacceptable risks to ecological receptors. Specifically, EPA used the surface soil and
groundwater data generated during the RI to assess risk for both aquatic and terrestrial
invertebrates, fish, and wildlife (i.e., ecological receptors) by comparing measured
concentrations of Site contaminants in soil and groundwater with ecological SLs established for
soil and surface water, respectively. Because the Site is located in a heavily developed urban
area, potential ecological receptors are limited, and EPA did not identify any special habitats or
endangered species threatened by Site contaminants. However, the maximum concentration of
two Site contaminants exceeded their respective screening values in at least one sample of soil or
groundwater.
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In soil, cis-l,2-Dichloroethene (cis-l,2-DCE), exceeded its screening value in the 1- to 2-foot
depth interval of a single sample taken in the vicinity of the former Masterwear facility. Due to
the low frequency of detection of cis-l,2-DCE in soil, the absence of suitable wildlife habitat in
the vicinity of the location where the sample exceedance was identified, and the fact that this was
the only Site contaminant to exceed its respective SL, EPA concluded that Site contaminants in
soil do not require further evaluation relative to ecological risk.
In groundwater, PCE exceeded the surface water screening value in shallow groundwater in 3 of
45, 5 of 63, and 5 of 62 samples in the three phases of sampling, respectively. However,
contaminants confined to groundwater do not present ecological risk because there is no
exposure pathway through which ecological receptors could be exposed to contaminants in
groundwater.
Therefore, EPA concluded in the SLERA that COC concentrations in soil and groundwater do
not present significant risk to ecological receptors and that no further evaluation relative to
ecological risk at the Site is necessary.
7.3 Basis for Taking Action
The response action selected in this ROD is necessary to protect the public health or welfare or
the environment. It provides the basis for taking action and identifies the contaminants and
exposure pathways that need to be addressed by a remedial action.
8.0 Remedial Action Objectives
RAOs are specific goals developed to protect human health and the environment based on
unacceptable risks calculated in the Site-specific risk assessment, anticipated current and future
land use, objectives and expectations of the action, and statutory requirements. The RAOs
provide the basis for developing cleanup options that will be protective of human health and the
environment. The RAOs address Site-related receptor and pathway risks and hazard exceedances
based on the results of the risk assessment. Preliminary remediation goals (PRGs) were identified
by using established cleanup criteria such as MCLs, Regional SLs, and VISLs.
EPA developed the following RAOs specific to this remedial action:
• Protect human health by reducing or eliminating exposure (via ingestion, inhalation, or direct
contact) to groundwater COCs at concentrations that could pose an unacceptable risk to
human health for current and future groundwater use.
• Reduce COC concentrations in groundwater to restore the aquifer to its beneficial use as a
drinking water aquifer within a reasonable timeframe7.
'Currently the City of Martinsville is effectively using this aquifer as a drinking water source because it treats the
groundwater before providing it to customers. This RAO is more specifically intended to restore the groundwater in
the aquifer to drinking water standards before treatment.
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• Protect human health by reducing or eliminating the potential for COCs in soil, soil vapor, or
groundwater to volatilize and migrate into buildings through the VI pathway.
• Protect human health by reducing or eliminating exposure (via inhalation) to COCs in indoor
air, resulting from the intrusion of soil vapors, at concentrations that could pose an
unacceptable risk to human health for current and future use of affected properties.
To meet these RAOs, EPA is proposing the following PRGs:
• Groundwater8:
o SDWA MCL for PCE = 5 |ig/L
o SDWA MCL for TCE = 5 |ig/L
o SDWA MCL for cis-l,2-DCE = 70 |ig/L
o SDWA MCL for vinyl chloride = 2 |ig/L
• Soil Vapor9:
o Residential:
¦ 70 |ig/m3 for TCE
¦ 1,390 |ig/m3 for PCE
o Commercial/industrial:
¦ 292 |ig/m3 for TCE
¦ 5,840 |ig/m3 for PCE
9.0 Description of Alternatives
CERCLA Section 121(b)(1), 42 U.S.C. § 9621(b)(1), mandates that remedial actions must be
protective of human health and the environment, be cost-effective, comply with applicable or
relevant and appropriate requirements, and utilize permanent solutions, alternative treatment
technologies, and resource recovery alternatives to the maximum extent practicable.
In the feasibility study (FS), EPA developed and evaluated cleanup alternatives for groundwater
and soil vapor to address the current and potential risks to human health or the environment at
the Site. EPA initially developed eight cleanup alternatives for groundwater and five cleanup
alternatives for soil vapor. After an initial analysis, EPA rejected three of the groundwater
treatment alternatives and one of the soil vapor treatment alternatives and conducted a more
8 PRGs are included for PCE breakdown products as EPA anticipates it may detect these during the course of the
response action.
9 A discussion of how these values were determined can be found in Section 2.3 of the FS Report. The need for
VIMS will be determined first by sub-slab soil vapor concentrations. EPA, in consultation with IDEM, will
determine the need to include an additional evaluation for indoor air concentrations and, if it is deemed necessary,
will establish target indoor air concentrations based on the most recent health protective data available at that time.
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detailed evaluation of the remaining five groundwater treatment alternatives and four soil vapor
treatment alternatives.
The eight groundwater treatment alternatives that EPA initially analyzed included:
• GW1 = The "no action" alternative, which is included as a baseline of comparison.
• GW2 = Options for treatment at the City' s WTP.
• GW3 = Monitored natural attenuation (MNA) and ICs.
• GW4 = Enhanced in-situ bioremediation, long-term monitoring (LTM), and ICs.
• GW5 = In-situ chemical reduction (ISCR), LTM, and ICs.
• GW6 = In-situ chemical oxidation (ISCO), LTM, and ICs.
• GW7 = In-situ sorptive-reactive media, LTM, and ICs
• GW8 = In-well air stripping, LTM, and ICs.
The five soil vapor alternatives that EPA initially analyzed included:
• SV1 = The no action alternative.
• SV2 = Pathway sealing, LTM, and ICs.
• SV3 = Pathway sealing, VIMS, LTM, and ICs.
• SV4 = Soil vapor source removal, LTM, and ICs.
• SV5 = Pathway sealing, soil vapor source removal, VIMS, LTM, and ICs.
In its initial analysis, EPA rejected GW4, GW7, GW8, and SV2. EPA's initial analysis of these
alternatives and reasoning for rejecting alternatives for further evaluation can be found in Section
3 of the FS report for the Site10.
A summary of the cleanup alternatives for which EPA conducted a detailed analysis to consider
for this response action is provided below.
To calculate the present value of future costs, EPA used the discount factor identified by the
Office of Management and Budget when EPA drafted the FS, 2.6%.
9.1 Common Elements
All of the remedial alternatives, except the no action alternative, include the following common
elements:
• Access to private properties and public rights-of-way as necessary to conduct monitoring and
implement response actions;
• Treatment of the groundwater at the City's WTP before it is provided to the City's customers
(provided the wellfield remains at or near the same location);
10 EPA conducted a subsequent evaluation of GW7 after receiving comments which it summarized in a technical
memorandum that can be found in the AR for the Site with document ID number 958369.
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• Connection of private residences to the City's public drinking water supply if needed11; and
• Groundwater and VI sampling.
As needed to address residual risk remaining until the clean-up alternatives meet PRGs, EPA
may implement the following ICs:
• Recording the Site contamination in the land record to provide notice of the issue to
prospective landowners and the public.
• Recording contaminated aquifers on the state registry to maintain institutional tracking.
• Working with State and/or local regulators to develop ordinances or other regulations that
would achieve the following IC objectives:
o Prohibit the installation of potable wells in groundwater at the Site that is above
SDWA MCLs;
o Close potable wells and/or reduce the use of potable wells in groundwater at the
Site above SDWA MCLs; and/or
o Require construction of new, occupiable structures at the Site overlying
groundwater or soil vapor concentrations greater than VISLs to include protective
measures, such as vapor barriers or sub-slab depressurization systems.
9.2 Groundwater Alternatives
For the two active groundwater alternatives presented below, GW5 and GW6, EPA evaluated
active treatment in only the core of the groundwater plume. For these evaluations, EPA defined
the "core of the groundwater plume" as that portion of the groundwater plume with PCE
concentrations greater than 46 jj.g/1.
Alternative GW1—No Action
EPA is required to evaluate a "no action" alternative when considering potential remedial actions
for a site to provide a baseline for comparison to the other potential response actions. The no-
action alternative means that no remedial action would be undertaken and that no institutional
controls, containment, removal, treatment, or other mitigating actions would be implemented to
11 EPA is proposing to provide for private residences to connect to the city's municipal water supply if said
residence is dependent on a private well for drinking water and the private well is within the plume and screened at a
depth that has been impacted by site contamination. EPA estimates the cost for a single installation to be $4,000 and
that the number of residences needing this connection are very low since previous efforts revealed none. Therefore,
EPA estimates that the potential cost from these connections are insignificant in comparison to the cost of the active
groundwater remedies.
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control exposure to COCs. For the purpose of conducting the evaluation of this alternative, EPA
assumed that the City would no longer continue to treat water from its municipal wellfield.
Therefore, the potential human health and environmental risks associated with exposure to the
COCs which EPA identified in its risk assessments would not be mitigated. In addition,
contamination from the Site would not be contained and could spread and expand the Site
boundaries.
Estimated Costs for Alternative GW1
Direct Capital Costs: $0
O&M Costs: $0
Total Periodic Costs: $0
WTP Costs: $0
Total Present Value: $0
Alternative GW2—WTP Options
Alternative GW2 is a group of options that EPA considered for treating the water at the City's
WTP. The City is currently using GAC for treating the drinking water from its WTP, and EPA
evaluated this in comparison to two other viable options. This alternative would continue to treat
the groundwater extracted from the City's WTP before the water is provided to its customers and
protect those customers, the residents of the City of Martinsville, from exposure to groundwater
contamination via the drinking water pathway.
EPA assumed the treatment option selected as part of this alternative would be implemented
concurrently with any of the other groundwater treatment alternatives selected. Because the
WTP treatment would be a part of a more comprehensive groundwater treatment alternative, the
City is already effectively treating the drinking water at its WTP, and continued treatment at the
WTP is imperative to continued protection of the drinking water pathway, EPA did not conduct a
full detailed analysis of these options. Instead, EPA compared GAC treatment to other effective
treatment options to determine if GAC would continue to be the most effective and cost-efficient
option.
For its evaluation of the Alternative GW2 options, EPA assumed that the City will continue
pumping from the three existing municipal extraction wells at a similar rate and that treatment
will continue until the groundwater at the Site meets the PRGs.
EPA evaluated three different treatment technologies to reduce PCE concentrations to meet
drinking water standards in groundwater that is already being pumped for municipal use. The
three GW2 treatment technologies are:
• Option GW2A. Option GW2A would continue operations of the City WTP using GAC
treatment to reduce PCE concentrations to below the MCL.
• Option GW2B. Option GW2B would replace the existing GAC treatment system with an
air stripper. Air strippers remove COCs from liquid (water) by providing contact between
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the liquid and air. The air is then released to the atmosphere or potentially treated to
remove the COCs and subsequently released to the atmosphere.
• Option GW2C. Option GW2C would replace the existing GAC treatment system with an
advanced oxidation process treatment system. Advanced oxidation process treatment
combines ultraviolet light or ozone with hydrogen peroxide to form hydroxyl radicals,
which are powerful oxidants that effectively oxidize recalcitrant organic compounds (like
PCE).
EPA estimated that the O&M and total periodic12 costs presented would be incurred annually for
Options GW2B and GW2C and every 2 years for Option GW2A. Though the number of years
that these WTP options would need to be operated varies depending on the overall groundwater
remedy selected, the total present value presented below for each of the three WTP options is
based on 17 years of operation, which represents the longest estimate for the selected remedy to
achieve PRGs and makes the costs directly comparable.
Estimated Costs for WTP Options
Estimated Costs for
Option GW2A
Estimated Costs for
Option GW2B
Estimated Costs for
Option GW2C
Direct Capital Cost
$0
$627,484
$2,384,051
O&M Costs
$61,500
$62,143
$272,345
Total Periodic Costs
$87,514
$0
$0
Total Present Value
$1,119,113
$1,472,648
$6,088,050
After evaluating these three WTP options, EPA has determined that continued use of GAC for
treatment at the City's WTP is the best option. In each of the subsequent evaluations of
groundwater treatment alternatives, EPA assumes continued use of GAC at the City's WTP.
Alternative GW3—MNA and ICs
Alternative GW3 addresses the risk to current and potential future receptors by relying on natural
attenuation to decrease COC concentrations in groundwater and using institutional controls to
prevent COC exposure while natural attenuation is ongoing. The following are the main
components of Alternative GW3:
• MNA, including the following:
o Sampling and analyzing groundwater samples to assess natural attenuation of COCs
in groundwater; and
o Modeling groundwater and natural attenuation processes.
12 Periodic costs are costs that are expected to be encountered while the treatment alternative is being implemented
that do not fit in the O&M or direct capital costs categories.
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• Implementing institutional controls to prevent domestic use of untreated groundwater within
or nearby the plume.
Each of the main components of this alternative is discussed in the following paragraphs.
EPA defines MNA as "the reliance on natural attenuation processes (within the context of a
carefully controlled and monitored clean-up approach) to achieve site-specific remedial
objectives within a timeframe that is reasonable compared to other methods." Natural attenuation
processes include a variety of physical, chemical, or biological processes that act without human
intervention to reduce the contaminant mass, toxicity, mobility, volume, or concentrations in soil
and groundwater. Biodegradation is the most important destructive attenuation mechanism,
although abiotic destruction of some compounds does occur. Nondestructive attenuation
mechanisms include sorption, dispersion, dilution from recharge, and volatilization.
MNA is appropriate as a remedial approach only when it can be demonstrated to be capable of
achieving the RAOs within a timeframe that is reasonable compared to that offered by other
methods. MNA is typically applied in conjunction with active remediation measures (e.g., source
control13) or as a follow-up to active remediation measures that have already occurred.
Evaluating natural attenuation usually involves both determining what natural attenuation
processes are occurring and estimating future results of these processes. Therefore, if EPA were
to select this remedy, it would include continued monitoring and data evaluation over time to
document and verify the effectiveness of these processes. The evaluation may consist of
groundwater or fate-and-transport modeling to predict the effects of natural attenuation. The
evaluation method may also be updated periodically to verify progress and compare groundwater
analysis results to the predictions.
In addition to modeling, the use of natural attenuation as part of the remedial plan would require
that an LTM program be instituted. The monitoring data would provide information to allow
EPA to decide if natural attenuation is meeting Site objectives and to verify that changes in Site
conditions do not reduce the effectiveness of natural attenuation. Groundwater would be
monitored to determine if COC concentrations within the plume decrease as the result of existing
natural attenuation processes or if additional remedial action would be required. The existing
monitoring well network would be used to monitor groundwater COC concentrations,
breakdown products, geochemical conditions, and natural attenuation parameters, including
dissolved oxygen, oxidative-reductive potential (ORP), turbidity, pH, and conductivity. A
detection plan for early warning of potential impacts to sensitive receptors, such as users of
residential wells, would be provided. Plans could also be developed for contingent remedial
efforts that could be executed if natural attenuation processes do not fulfill expectations.
ICs implemented as part of this remedy would protect human health and the environment until
natural attenuation processes (or a contingent remedy) reduce COC concentrations in
groundwater to below PRGs. The specific ICs EPA would implement would prevent exposure to
and use of contaminated groundwater at the Site. EPA may also require access agreements and
13 EPA previously oversaw the operation of an SVE/AS system that was designed to remediate the primary
contaminated soil and groundwater source at the Site and does not expect source control to be necessary at the Site.
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property restrictions to install and protect groundwater monitoring wells and other response
infrastructure.
For the estimated total present value for Alternative GW3 presented below, EPA assumed 35
years of groundwater monitoring and operation of the carbon treatment on the WTP (Option
GW2A). EPA estimates that it will take 34 years for natural attenuation to achieve groundwater
PRGs and has included an extra year of monitoring to confirm groundwater concentrations
remain below PRGs. The periodic costs presented below would be incurred every 5 years.
Estimated Costs for Alternative GW3:
Direct Capital Costs: $158,933
Annual O&M Costs: $84,050
Total Periodic Costs: $42,081
WTP Costs: $1,934,435
Total Present Value: $3,285,377
Estimated Time for Alternative GW3 to reach PRGs: 34 years
Alternative GW5—ISCR, LTM, andlCs
Alternative GW5 addresses the risk to current and potential future receptors using ISCR and
institutional controls to prevent COC exposure until ISCR and natural attenuation reduce
groundwater COCs to below PRGs. ISCR involves injecting an insoluble chemical amendment,
such as zero-valent iron (ZVI), with or without carbon sources, in solid or slurry form into the
groundwater plume to create a zone with strongly reducing conditions, triggering and
accelerating reductive dechlorination of the COC contaminants.
The following are the main components of Alternative GW5:
In situ chemical reduction, including the following:
o Injecting ISCR amendments into the subsurface within the core of the shallow
groundwater plume to stimulate abiotic and biotic processes; and
o Relying on MNA to achieve the PRGs for the areas of the plume with lower COC
concentrations.
LTM, including sampling and analyzing groundwater samples for COCs and daughter
products.
• ICs to prevent domestic use of untreated groundwater within or nearby the plume.
Both ICs and LTM would be implemented for Alternative GW5 in the same manner as for
Alternative GW3.
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Alternative GW5 would primarily consist of injecting ISCR amendments into the shallow aquifer
to promote ISCR. Injecting an ISCR reagent consisting of a combined ZVI and carbon source
has proven to be highly effective in treating chlorinated compounds based on oxidation-reduction
processes where the contaminant serves as an electron acceptor and the ISCR reagent as the
electron donor. Chlorinated compounds can accept electrons from ZVI and be chemically
reduced to nontoxic end products, such as ethene and ethane. In addition to the chemical
component of ISCR, the reduced conditions in groundwater created by the ZVI are also
favorable for stimulating the growth of microorganisms capable of degrading compounds.
Bacterial cultures that facilitate this degradation may need to be including in the ISCR
amendments. These would be injected after a reducing environment has been established, as
these bacteria that thrive under reducing conditions are often not present in aerobic aquifers. In
addition, if ZVI is combined with nutrients and an electron acceptor or energy source, several
physical, chemical, and microbiological processes combine to create strong reducing conditions
that stimulate rapid and complete dechlorination of organic solvents. These biogeochemical
reductions minimize the generation of daughter products, such as vinyl chloride, and result in
end products of ethene and ethane.
Injections would be accomplished using a permanent network of wells or by temporary injection
wells through DPT and associated screened injection tools. Injection points could be spaced on a
grid pattern at the Facility or in off-set rows to create a reactive zone to intercept contaminated
groundwater.
The geochemical conditions induced by ISCR could also induce biotic processes in
downgradient portions of the groundwater plume and could help to reduce COC concentrations
to below the PRGs within the remainder of the groundwater plume.
Predesign investigations may be conducted to refine estimates of contaminant mass and depth
intervals or to collect remedy-specific parameters. During and after treatment, performance
monitoring would be conducted to establish baseline conditions at the Site prior to remediation,
determine the degree of contaminant reduction, and monitor contaminant migration. The
potential for methane generation and need for methane control during remediation would also be
evaluated before and during treatment. Parameters specific to the performance of ISCR would
also be monitored during treatment, such as ISCR amendments, microorganisms, pH, ORP,
dissolved oxygen, methane, ethane, ethene, and general chemistry. EPA would use this
performance monitoring to evaluate if additional injections are necessary and, if so, whether it is
more technically and economically effective to continue with the same ISCR amendment or to
focus on promoting the biotic processes leading to reductive dehalogenation.
For the estimated total present value for Alternative GW5 presented below, EPA assumed two
injection events would be conducted and that LTM and WTP operation (Option GW2A) would
continue for 17 years. This is the amount of time EPA estimates will be required for natural
processes to reduce COC concentrations in groundwater to below PRGs after the initial injection
of ISCR amendments decrease concentrations in the core of the plume, using the most
conservative assumption scenario in the FS (see Appendix E of the FS). The annual O&M costs
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are presented as a range because EPA estimates this cost to vary by year, as detailed in the FS
report. The periodic costs presented below would be incurred every 5 years.
Estimated Costs for Alternative GW5:
Direct Capital Costs:
Annual O&M Costs:
Total Periodic Costs:
WTP Costs:
$1,337,696
$82,027 - $404,907
$42,081
$1,119,113
$4,382,898
Total Present Value:
Estimated Time for Alternative GW5 to reach PRGs: 9 to 17 years14
Alternative GW6—ISCO, LTM, andlCs
Alternative GW6 consists of injecting a liquid chemical oxidant (persulfate, permanganate, or
peroxide) into the shallow groundwater. The following are the main components of Alternative
• ISCO, including the following:
o Injecting an oxidant into the subsurface to oxidize COCs within the core of the
shallow groundwater plume; and
o Relying on MNA to achieve the PRGs for the areas of the plume with lower COC
concentrations.
• LTM, including sampling and analyzing groundwater samples for COCs and daughter
• ICs to prevent domestic use of untreated groundwater within or nearby the plume.
ICs and LTM would be implemented for Alternative GW6 as discussed for Alternatives GW3
ISCO involves oxidation, a chemical process that can convert hazardous contaminants, such as
PCE, to nonhazardous or less toxic compounds that are inert, more stable, or less mobile.
Alternative GW6 would primarily consist of injecting a chemical oxidant into the core of the
groundwater plume within the shallow aquifer to treat the COCs present in the core of the
groundwater plume. The COCs would be converted into innocuous compounds commonly found
in nature, such as carbon dioxide, water, and inorganic chloride.
14 In the FS, EPA used two different sets of assumptions for estimating the amount of time active treatment using
Alternative GW5 followed by natural attenuation would reduce site groundwater contaminants to below PRGs. The
differences in the assumptions are specific to the assumed effectiveness of active treatment. As such, EPA is
reporting this estimated timeframe as a range. More details can be found in Appendix E of the FS Report.
GW6:
products
and GW5.
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The oxidants that may be applicable to the Site include permanganate and persulfate, which have
been used for the remediation of chlorinated solvents like PCE. Permanganate is commonly
available in two forms: potassium permanganate, a crystalline solid that is typically mixed with
water onsite to form a solution; and a liquid sodium permanganate. Compared to other oxidants,
permanganate is relatively stable and persistent in the subsurface; as a result, it can migrate by
diffusive processes, allowing it to treat more of the groundwater plume. Persulfate typically must
be activated in the field by applying iron ethylenediaminetetraacetate or a base, such as sodium
hydroxide, to increase pH. For persulfate to be effective in field applications, the activator must
be distributed and transported with the persulfate. Natural mineral activated persulfate using
ambient groundwater minerals would also be considered.
As discussed for Alternative GW5, injections would be accomplished using a permanent network
of injection wells or temporary injection wells using DPT and screen tools. The oxidant would be
injected into the subsurface, exit the well screens (if applicable), and spread laterally into the
aquifer formation. The oxidant would mix and react with the COCs in the surrounding
groundwater. Recirculation wells or injection and extraction well combinations may be
employed to improve mixing and oxidant distribution in the subsurface. Fewer injection wells
would be required using these delivery approaches. This could be an advantage as the
groundwater plume is located below a highly developed area.
The injection points could be arranged in rows to create a reactive zone to intercept contaminated
groundwater. If necessary, injection points could also be spaced on a grid pattern within the
parking lot of the Facility. As with Alternative GW5, the injections would be focused on treating
the core of the groundwater plume with the highest PCE concentrations. After the initial
injection period, an evaluation would be conducted to determine if additional injections are
necessary.
Predesign investigations would be performed to refine the COC mass estimate and vertical
intervals for injections. During and after treatment, performance monitoring would be conducted
to establish baseline conditions at the Site prior to remediation, determine the degree of
contaminant reduction, and monitor contaminant migration. Parameters specific to the
performance of ISCO would also be monitored, such as oxidant concentrations, metals that may
be solubilized due to highly oxidative conditions (e.g., arsenic, barium, cadmium, chromium,
lead, or selenium), pH, ORP, dissolved oxygen, and general chemistry.
For the estimated total present value for Alternative GW6 presented below, EPA assumed two
injection events would be conducted and that LTM and WTP operation (Option GW2A) would
continue for 15 years. This is the amount of time EPA estimates will be required for natural
processes to reduce COC concentrations in groundwater to below PRGs after the initial injection
of ISCO amendments decrease concentrations in the core of the plume, using the most
conservative assumption scenario in the FS (see Appendix E of the FS). The annual O&M costs
are presented as a range because EPA estimates this cost to vary by year, as detailed in the FS
report. The periodic costs presented below would be incurred every 5 years.
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Estimated Costs for Alternative GW6:
Direct Capital Costs:
Annual O&M Costs:
Total Periodic Costs:
WTP Costs:
$1,913,970
$82,027 - 346,058
$42,081
$1,003,034
$4,266,387
Total Present Value:
Estimated Time for Alternative GW6 to reach PRGs: 11 to 15 years15
9.3 Soil Vapor Alternatives
In the FS, EPA conducted an initial analysis of 5 soil vapor alternatives but conducted a detailed
evaluation of 4 of these soil vapor alternatives. In this ROD, EPA is only presenting the 4 soil
vapor alternatives for which it conducted a detailed analysis. EPA presents its rationale for
screening out 1 of the initial 5 soil vapor alternatives in the FS report.
Alternative SV1—No Action
EPA is required to evaluate a "no action" alternative when considering potential remedial actions
for a site to provide a baseline for comparison to the other potential response actions. The no-
action alternative means that no remedial action would be undertaken and affected soil vapor
would remain at the Site without implementing any institutional controls, containment, removal,
treatment, or other mitigating actions to control exposure to COCs. Therefore, the potential
human health and environmental risks associated with exposure to the COCs would not be
mitigated.
Direct Capital Costs: $0
Alternative SV3—Pathway Sealing, VIMS, LTM, and ICs
Alternative SV3 consists of installing active or passive VIMS for existing buildings to reduce
COCs in indoor air. The following are the main components of Alternative SV3:
• Pathway sealing to close the preferential routes of VI into buildings.
• VIMS, including the following:
15 In the FS, EPA used two different sets of assumptions for estimating the amount of time active treatment using
Alternative GW6 followed by natural attenuation would reduce site groundwater contaminants to below PRGs. The
differences in the assumptions are specific to the assumed effectiveness of active treatment. As such, EPA is
reporting this estimated timeframe as a range. More details can be found in Appendix E of the FS Report.
O&M Costs:
Total Periodic Costs:
Total Present Value:
$0
$0
$0
o Performing predesign diagnostic testing for design of a VIMS;
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o Installing a VIMS for each building where COCs in indoor or crawlspace air pose
an unacceptable risk to human health due to the VI pathway;
o Operating active VIMS in buildings where selected as the appropriate mitigation
measure; and
o Performing O&M activities and monitoring the performance of the VIMS.
• LTM, including the following:
o Sampling and analyzing indoor, outdoor, and crawlspace air samples for COCs
and daughter products; and
o Sampling and analyzing sub-slab soil vapor samples for COCs and daughter
products, if warranted.
• Coordination with the City to identify any ICs that could be utilized to encourage new
construction to include measures to prevent soil vapors from accumulating in indoor air.
• ICs as needed to ensure the integrity of the VIMS.
Pathway Sealing: Cracks and openings in the building foundation are the preferential routes of
vapor entry, rather than diffusion through the concrete slab itself. Thus, an important first step in
preventing VI is to seal preferential vapor entry points, which can include the following:
• Cracks or holes in the building walls, floors, slabs, and foundation;
• Gaps in and around fieldstone walls, utilities, floor drains, dry utilities, and pipes;
• Construction joints between walls and slabs;
• Floor and utility penetrations, such as those for plumbing, sewer drainage, heating ducts,
and electrical conduit; and
• Floor drains and open sumps.
As part of Alternative SV3, each building to be sealed would be thoroughly inspected to identify
preferential vapor entry points prior to initiating further remedial action. The base of the building
envelope would be visually inspected to identify cracks, building joints, and other building
features that could be potential soil vapor entry points. In addition, potential entry points could
be surveyed with a portable photoionization detector or a portable gas chromatograph/mass
spectrometer. It is often possible to find elevated concentrations of COCs at particular points
(that is, preferential pathways) where VI is occurring. The sealing technique would be selected to
be appropriate for each type of vapor entry point. Periodic maintenance and visual inspections of
the seal could be performed, and appropriate repairs would be made as needed.
Long-term Monitoring: LTM would be conducted to identify areas where VI from the Site
remains a threat and, where appropriate, to assess potential VI in occupied structures. LTM could
include sampling for COC concentrations in soil vapor in exterior soil vapor probes or wells in
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addition to sampling for COC concentrations in indoor air, crawlspace air, and/or sub-slab soil
vapor. Samples (particularly those in and under occupied structures) would be collected during
multiple seasons, including during both heating and cooling seasons. Outdoor ambient air would
be concurrently sampled for COCs to determine if contaminants are likely to be attributable to
VI rather than ambient sources. Though the frequency of LTM may vary, it would continue as
long as the VI pathway continues to present an unacceptable risk to human health.
VIMitigation: An appropriate mitigation measure would be designed and implemented for each
occupied structure where COCs in indoor or crawlspace air from VI pose an unacceptable risk to
human health. EPA may also elect to implement mitigation measures at occupied structures
where there is the potential for COCs from VI to pose a future risk to human health. Future risk
may be assessed by COC concentrations in soil vapor or sub-slab soil vapor. Mitigation
measures can generally be classified as active or passive technologies. Active VIM technologies
would be implemented in occupied structures where there is current unacceptable risk to human
health. EPA could elect to implement passive or active VIM technologies for occupied structures
with no current but a potential future unacceptable risk from VI.
A common active mitigation measure is active depressurization technology (ADT), which has
been used successfully to mitigate the VI pathway into residential, commercial, and school
buildings. ADT systems are widely considered the most practical VIM strategy for most existing
buildings, including those with basement slabs or slab-on-grade foundations. ADT systems are
generally recommended for consideration for VIM because of their moderate cost and their
demonstrated capability to achieve significant concentration reductions in a wide variety of
buildings. SSD systems, a common type of ADT system, function by creating a pressure
difference across the building slab to prevent soil vapor from entering the building, thus
overcoming the building's natural under-pressurization, which is the driving force for VI.
Alternative SV3 would include installing SSD systems in occupied structures with a basement
slab or slab-on-grade and where ADT is warranted. The SSD system would be constructed by
coring one or more holes through the existing slab, removing soil from beneath the slab to create
a suction pit, placing vertical suction pipes into the holes, and sealing the openings around the
pipes. These pipes would be manifolded and connected to powered mitigation fans or blowers.
The fans would extract soil vapor collected from the targeted sub-slab area, creating a negative
pressure field between the sub-slab and indoor spaces. The extracted air would be discharged to
the atmosphere outside the structure at a height above the outdoor breathing zone and away from
windows and air supply intakes. As part of the design process, pre-mitigation diagnostic testing
may be required to optimize the VIMS design.
In buildings with a crawlspace or basement with an earthen floor, a vapor-resistant membrane
would be placed over the ground to retard the flow of vapor into the building. The membrane
would be sealed to the walls of the building, and one or more suction points would be fitted
through the membrane using a gasket. This type of system is referred to as submembrane
depressurization (SMD) and is like an SSD, except that the membrane is used as a surrogate for a
slab to depressurize the soil.
Before or shortly after VIMs are installed, an operation, maintenance, and monitoring (OM&M)
plan would be prepared to identify activities that should be performed following start-up of the
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system and a schedule for conducting these activities, including an exit strategy for discontinuing
SSD/SMD system operation. The SSD/SMD systems would be inspected periodically which
could include measuring field parameters and conducting visual inspections. Routine inspections
would also include evaluating significant changes made to the building that would impact the
design of the mitigation system or the environment in which it is operated. Routine maintenance
of the systems may include periodic fan replacement.
Passive venting relies on natural diffusion, natural pressure gradients, the stack effect, or wind-
driven ventilation fans to cause soil vapor to migrate to collection pipes and exhaust to the
atmosphere. Passive systems generally have the same components as active systems, except that
they do not include electric-powered fans. As a contingency measure, the passive system could
be converted to an active system if needed.
For future construction, VIM technology may include barriers, such as geomembranes or spray-
applied membranes. Other technologies for new buildings that could be considered include
passive venting layers and aerated floor systems.
ICs: ICs could be a necessary part of this remedy to protect human health. For example, land-use
controls could be implemented at the Site in areas where VI sampling indicates that the VI
pathway potentially presents an unacceptable risk. Prior to remediation of the groundwater
plume, ICs may be needed for future construction at the Site to allow for VI sampling and/or
mitigation. EPA expects that such ICs would be in effect on an interim basis until the cleanup
goals are met and unacceptable risk to human health is no longer present.
For the estimated total present value for Alternative SV3 presented below, EPA assumed that the
indoor air action level triggering the need for a VIMs based on an HI of 1 (or an ELCR 10"5) and
that 34 residential and 21 commercial buildings would need VIMS. EPA estimated that the
VIMS would need to be operated for 30 years, which assumes that contaminant levels will no
longer pose a VI risk at that time. EPA expects that the needed timeframe for operation of VIMS
will be primarily dependent on the performance on the groundwater cleanup activities and that
30 years is a conservatively long estimate.
EPA estimated two sets of periodic costs as detailed below, one cost to be incurred every 5 years
and another cost to be incurred every 10 years.
Direct Capital Costs: $4,961,904
Annual O&M Costs: $91,632
Total Periodic Costs (every 5 years): $36,101
Total Periodic Costs (every 10 years): $275,573
Total Present Value: $7,430,653
Alternative SV4—Soil Vapor Source Removal, LTM, and ICs
Alternative SV4 primarily relies on removing sources of soil vapor contamination to decrease
COC concentrations in soil vapor that act as the driving force for VI. The following are the main
components of Alternative SV4:
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• Soil vapor source removal, including the following:
o Installing and operating an SVE system or multiple SVE systems to address high-
concentration soil vapor areas; and
o If needed, excavating shallow soil within the Facility parking lot that may be
acting as a source of COCs in soil vapor.
• LTM.
• ICs as needed to allow for installation and protection of response action infrastructure.
This alternative would include LTM and ICs as described for Alternative SV3. The remaining
component of this alternative is discussed in the following paragraphs.
Soil Vapor Source Removal: Alternative SV4 would reduce a significant source of soil vapor
contamination via SVE and would be supplemented by excavation, if sufficient soil
contamination is found to warrant direct removal.
Residual soil contamination may be contributing to COCs in soil vapor. The highest PCE and
TCE concentrations were detected within the 1- to 2-feet depth interval of SG-1, which is in the
Facility parking lot. The soil within the immediate vicinity of this sample location could be
excavated and transported offsite for disposal. The goal of soil excavation would be to remove
contaminated soil acting as a continuing source of soil vapor contamination from an area near the
Facility that is readily accessible. Waste characterization sampling would determine whether the
soil would be disposed of as hazardous or nonhazardous waste. Following excavation, the
excavated area would be backfilled with clean fill material from an offsite source, and site
restoration would be performed.
EPA identified 3 main areas with particularly elevated PCE concentrations in soil vapor (greater
than 15,000 [j,g/m3 - See Figure 3). In addition to soil excavation, Alternative SV4 would also
include installing SVE systems within one or more of the high-concentration PCE soil vapor
areas. At a minimum, an SVE system would be installed in the area surrounding the Facility. The
goal of an SVE system would be to treat the source of soil vapor contamination that cannot be
readily addressed by excavation. The most elevated TCE concentrations in soil vapor (greater
than 1,000 (j,g/m3) are near the Facility and would be among the areas addressed by this system.
SVE wells could be installed beneath the Facility using directional drilling to address residual
soil contamination. Secondary systems could also be installed to address the two additional areas
with elevated PCE concentrations in soil vapor, one to the northwest of the Facility (near HAP-
023 and HAP-084) and one to the southeast of the Facility (near the former location of Central
Dry Cleaners). The need for these secondary systems would be determined as part of predesign
investigations. The extracted soil vapor would be treated to remove COCs prior to discharge to
the atmosphere if required by state and federal air discharge regulations.
Predesign activities would be required for the design of the SVE system(s). Soil samples may
also be collected in targeted areas as part of a predesign investigation to optimize the SVE design
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and to determine the need for secondary systems. If possible, soil samples would be collected to
assess if soil contamination is present beneath the Facility. A field pilot study would also be
conducted, if necessary, to establish the radius-of-influence and other design parameters for the
SVE system. Based on the results of the predesign activities, the SVE system could also be
thermally enhanced, if warranted.
OM&M would also be required for the SVE system(s), including periodic inspections, field
measurements, and performance verification. Maintenance of the SVE system(s) would include
periodic carbon replacement, if off-gas treatment is implemented, and system component
replacement, as needed.
For the estimated total present value for Alternative SV4 presented below, EPA assumed that the
SVE systems would be operated for 5 years. EPA estimates that the periodic costs presented
below would be incurred every 5 years.
Direct Capital Costs: $2,273,931
Annual O&M Costs: $224,372
Total Periodic Costs: $36,101
Total Present Value: $3,338,829
Alternative SV5—Pathway Sealing, Soil Vapor Source Removal, VIMs, LTM, andICs
Alternative SV5 is a combination of Alternative SV3 and SV4 in that it includes VIM for
individual buildings, as well as soil vapor source removal to address residual soil contamination
and high concentration soil vapor areas. The following are the main components of Alternative
SV5:
• Pathway sealing to close the preferential routes of VI into buildings.
• Soil vapor source removal, including the following:
o Installing and operating an SVE system or multiple SVE systems to address high-
concentration soil vapor areas; and
o If needed, excavating shallow soil within the Facility parking lot that may be
acting as a source of COCs in soil vapor.
VIM, including the following:
o Performing predesign diagnostic testing for design of the VIMS;
o Installing a VIMS for each building where COCs in indoor or crawlspace air pose
an unacceptable risk to human health due to the VI pathway; and
o Performing OM&M activities and monitoring the performance of the VIMS.
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• LTM, including the following:
o Sampling and analyzing indoor, outdoor, and crawlspace air samples for COCs
and daughter products; and
o Sampling and analyzing sub-slab soil vapor samples for COCs and daughter
products, if warranted.
• ICs as needed to allow for installation and protection of response action infrastructure.
The components for Alternative SV5 have been previously discussed as part of Alternatives SV3
and SV4.
For the estimated total present value for Alternative SV5 presented below, EPA assumed the
indoor air action level triggering the need for a VIMs based on an HI of 1 (or an ELCR of 10"5)
and that 34 residential and 21 commercial buildings would need VIMs. EPA also assumed that
the VIMS would be operated for 30 years. EPA estimates that the periodic costs presented
below would be incurred every 5 years.
Direct Capital Costs: $6,075,915
Annual O&M Costs: $304,150
Total Periodic Costs: $72,202
Total Present Value: $7,539,713
10.0 Comparative Analysis of Alternatives
Section 121(b)(1) of CERCLA identifies several factors that EPA is required to consider in its
assessment of remedial alternatives. Building on these specific statutory mandates, the NCP
articulates nine evaluation criteria to be used in assessing the individual remedial alternatives.
The purpose of this evaluation is to promote consistent identification of the relative advantages
and disadvantages of each alternative, thereby guiding selection of remedies offering the most
effective and efficient means of achieving site remediation goals. While all of the nine criteria
are important, they are weighed differently in the decision making process depending on whether
they evaluate protection of human health and the environment or compliance with federal and
State requirements, standards, and criteria (threshold); consider technical or economic merits
(balancing criteria); or involve evaluation from the State and the public that may influence the
final remedy selection (modifying criteria). Each of these nine criteria is described below.
Threshold Criteria
1. Overall Protection of Human Health and the Environment focuses on how an
alternative achieves protection over time and indicates how each source of contamination
would be minimized, reduced, or controlled through treatment, engineering, or
institutional controls. The evaluation of the degree of overall protection associated with
each alternative is based largely on the exposure pathways and scenarios set forth in the
baseline human health risk assessment.
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2. Compliance with ARARs addresses whether alternatives meet applicable or relevant and
appropriate federal and State requirements.
Balancing Criteria
3. Long Term Effectiveness and Permanence addresses the results of a remedial action in
terms of the risk remaining at the Site after response objectives have been met.
4. Reduction of Toxicity, Mobility or Volume through Treatment addresses the statutory
requirement for selecting remedial actions that employ treatment technologies that reduce
the toxicity, mobility or volume of the hazardous constituents present in the impacted
media to the maximum extent practicable.
5. Short-Term Effectiveness addresses the effects of the alternatives during the
construction and implementation phases (i.e. remediation risks) until the remedial action
objectives are met.
6. Implementability considers the technical and administrative feasibility of implementing
the remedial alternative, including factors such as the relative availability of goods and
services.
7. Cost includes estimated capital, annual O&M costs, and net present value of capital and
O&M costs including long term monitoring.
Modifying Criteria
8. State Agency Acceptance considers whether the State support Agency concurs with the
selected remedy for the Site.
9. Community Acceptance addresses the public's general response to the remedial
alternatives and the preferred alternative presented in the Proposed Plan.
Each of the nine evaluation criteria are discussed below with respect to the alternatives under
consideration for this P&M Site remedial action. The relative performance of each alternative for
remediating the groundwater plume and soil vapor contamination is evaluated against the nine
criteria, noting how it compares to the other options under consideration. A more detailed
analysis of each of the remedial alternatives can be found in Section 4.4 and Tables 4-9 and 4-10
of the FS report for the Site.
10.1 Comparative Analysis of Groundwater Alternatives
All groundwater alternatives except the no action alternative (Alternative GW1) include
continued operation of treatment operations at the WTP. For purposes of conducting the
evaluations of these groundwater alternatives in the FS, EPA assumed that WTP Option GW2A
(GAC treatment) would be used. GAC treatment has proven to be effective, requires no upfront
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capital costs, and is the most cost-efficient option in present value, even after an assumed 35-
year operating period, which represents the longest amount of time EPA estimates it would take
to achieve groundwater PRGs plus an extra year of monitoring.
1. Overall Protection of Human Health and the Environment
Alternative GW1 (No Action) is not protective because it allows for groundwater COC
concentrations exceeding PRGs to remain in place and potentially exposes current and future
receptors to COCs above acceptable levels, and it does not prevent or minimize plume migration.
Alternative GW3 is protective of human health and the environment, even though no active
treatment process is used, because it prevents access to contaminated groundwater through the
use of ICs and continued GAC treatment at the WTP. Modeling provided in the FS estimates that
PCE concentrations would decrease below the PRG in about 34 years.
Alternatives GW5 and GW6 include active in situ groundwater treatment in addition to ICs and
continued GAC treatment at the WTP. As such, these alternatives offer greater protection than
the other alternatives considered.
2. Compliance with ARARs
Alternative GW1 (No Action) does not comply with ARARs. Alternative GW3 would meet
chemical specific ARARs once natural attenuation processes have reduced PCE concentrations
within the plume to below the PRG. Alternatives GW5 and GW6 would comply with ARARs.
The primary ARARs to be met relate to reducing PCE concentrations in groundwater to below
their PRGs, treating off-gas if required, and proper management and disposal of waste generated
during the remedial action. Specific ARARs are listed in Table 2-1 of the FS report.
3. Long-term Effectiveness and Permanence
The long-term effectiveness and permanence of the alternatives are evaluated in terms of the
magnitude of residual risk, adequacy and reliability of controls, and potential environmental
impacts of the remedial actions.
The residual risk of Alternative GW1 (No Action) would remain unchanged until natural
attenuation processes reduced groundwater concentrations to levels no longer posing a risk. EPA
estimates this would take 34 years; however, this alternative proposes no monitoring to track or
confirm that. No active treatment processes would be used to reduce COC concentrations in
groundwater in Alternative GW3; however, EPA estimates that, after 34 years, the groundwater
would achieve PRGs through natural attenuation in conjunction with treatment at the City's
WTP (Alternative GW2), eliminating residual risk. No residual risks would be anticipated with
Alternatives GW5 and GW6 because both active treatment methods would be expected to reduce
COC concentrations to below a performance standard16, and then, natural attenuation processes
16 EPA will establish the initial performance standard for the active groundwater treatment during the remedial
design. For estimating purposes, EPA used two options for performance standards, 46 jxg/1 and 16 jxg/1. However,
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would eventually reduce COC concentrations to below their respective PRGs. However, if any
COC adsorbed on the aquifer matrix was to back-diffuse into the groundwater over time, it is
anticipated that the more persistent carbon substrate would make Alternative GW5 better able to
address this newly released PCE. Treatment chemicals used for Alternative GW5 and GW6 are
not expected to result in residual risks because of their short lifespan, ranging from 2 to 5 years,
and exposures not addressed by institutional controls are not expected to occur over this period.
Implementation of Alternative GW5 includes residual risks associated with methane generation
and/or formation and accumulation of more harmful daughter products, such as vinyl chloride.
EPA believes these residual risks can be managed with careful monitoring and the addition of
methane-inhibiting supplements. Similarly, implementation of Alternatives GW5 and GW6 both
include residual risks with increased dissolution of naturally occurring minerals into
groundwater, but this risk can be managed with careful design and monitoring.
Alternatives GW3, GW5, and GW6 include institutional controls that would be adequate and
reliable in preventing direct contact with and ingestion of untreated contaminated groundwater.
Additionally, Alternatives GW3, GW5, and GW6 would require LTM of COC concentrations
and natural attenuation parameters to monitor the progress of natural attenuation processes.
Alternatives GW5 and GW6 would also include monitoring to evaluate performance of the
remedy and to ensure that residual risks are being managed.
4. Reduction of Toxicity, Mobility, or Volume of Contaminants through Treatment
No treatment processes are used for Alternative GW1 and GW3; therefore, no reduction of
toxicity, mobility, or volume through treatment is anticipated. However, natural attenuation
processes would be expected to reduce concentrations of PCE to below its PRG in approximately
34 years. Alternatives GW5 and GW6 include in situ treatment via injection of a chemical
reductant and chemical oxidant, respectively; therefore, both alternatives would meet the NCP
preference for treatment. Alternative GW6 would be expected to treat more contaminant mass
than Alternative GW5 over the shorter timeframe, accelerating a decrease in toxicity, mobility,
and volume of PCE during the initial phase of implementation. However, EPA expects the
overall reduction in toxicity, mobility, and volume for GW5 and GW6 to be the same.
5. Short-term Effectiveness
No additional risks are associated with Alternative GW1 because no remedial action would be
taken, and no construction would be performed. The remedial option, other than No Action, that
would pose the least amount of risk in the short-term is Alternative GW3 because this option
contains the least amount of construction and work required as it is ongoing. Alternatives GW5
and GW6 would pose the most risk in the short-term because of the number of surface
penetrations required, the timeframe for injections, and the use of chemicals and potential
exposure to the community during implementation of the remedy. The overall difference in risk
between Alternatives GW5 and GW6 would be nominal, except for the type and quantity of
chemical used and the timeframe required for injection. The treatment chemicals used for
EPA expects the actual performance standard to be based on the ultimate goal of reducing concentrations with active
treatment to as close to PRGs as practicable.
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Alternative GW5 would pose less of a risk than the strong oxidants involved with Alternative
GW6. However, the potential exposures would be controlled through standard best management
practices, such as appropriate decontamination protocols, careful dosing, air monitoring, and
appropriate traffic control measures.
6. Implementability
Alternative GW1 requires no construction or treatment and would be the easiest to implement.
For costing purposes, Alternative GW3 assumes installation of three monitoring wells with
materials that are readily available. Alternatives GW5 and GW6 would have the greatest
implementability challenges because both alternatives are active treatment options requiring the
use of chemicals and injections. Alternative GW5 would be more difficult to implement than
Alternative GW6 because Alternative GW5 would involve injection of a viscous slurry into the
aquifer.
7. Cost
An overview of the cost analysis performed for this evaluation and the detailed breakdowns for
each of the alternatives are presented in Appendix D of the FS report. Total costs are
summarized below and include costs for the City WTP to continue to operate in its current
configuration (Option GW2A):
Alternative GW 1
Alternative GW3
Alternative GW6
Alternative GW5
$0
$3.29 million
$4.27 million
$4.38 million
8. State Agency Acceptance
IDEM supports the selected remedy: Groundwater Alternative GW5 in conjunction with
Groundwater Alternative GW2 (Option GW2A) and with the contingency that Groundwater
Alternative GW6 be used if EPA, in consultation with IDEM, determines that Groundwater
Alternative GW5 is ineffective or risks cannot be adequately managed. EPA received a February
11, 2021, letter from the Assistant Commissioner of IDEM expressing concurrence with the
selected remedy (Appendix B).
9. Community Acceptance
During the virtual public meeting and public comment period, the community expressed support
for Groundwater Alternative GW5 (ISCR). A number of commenters also expressed support for
the use of a second technology, sorbent reactive media, in addition to ISCR. EPA rejected this
analysis in its initial evaluation of alternatives in the FS. EPA revisited this evaluation after
receiving these comments but has determined that the use of this technology is not warranted or
appropriate at this time. No commenters expressed support for the implementation of a different
treatment technology than EPA's selection of continued use of GAC to treat the City's municipal
drinking water supply. Further details on the comments from the community and EPA's
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responses to those comments can be found in the Responsiveness Summary which is Part III of
this ROD.
10.2 Comparative Analysis of Soil Vapor Alternatives
1. Overall Protection of Human Health and the Environment
Alternative SV1 (No Action) would not be protective because there would be no remediation of
soil vapor, and exposures to current and future receptors would continue. Alternatives SV3 and
SV5 would be protective of human health because sub-slab soil vapors would be mitigated
through active SSD or SMD. Alternative SV4 would not be protective of human health in the
short-term because no VIMS are installed to address risk to current receptors. However,
Alternative SV4 would become protective of human health once soil vapor source removal
occurs and concentrations in soil vapor and indoor air are confirmed to be below remedial goals.
2. Compliance with ARARs
Alternative SV1 (No Action) would not comply with ARARs because no remedial actions would
be taken to address unacceptable risk. Alternatives SV3 and SV5 would comply with ARARs
because VIMSs would remove unacceptable risk to current and future receptors. Alternative SV4
would not comply with chemical-specific ARARs despite remedial actions being taken because
no VIMS would be installed to address risk to current receptors. Specific ARARs are listed in
Table 2-1 of the FS report.
3. Long-term Effectiveness and Permanence
The residual risk of Alternative SV1 (No Action) would remain unchanged. Alternative SV3
would address exposures leading to residual risks by implementation of VIMS, pathway sealing,
and ICs. However, because no soil vapor source removal would occur, residual risk would
remain until natural attenuation processes reduce concentrations in soil vapor to below PRGs.
Though EPA does not have enough data to estimate the rate of natural attenuation in soil vapor,
it expects this to be similar to the 34 years estimated for groundwater to achieve PRGs. VIMS
monitoring would be required to verify that COC concentrations in indoor air do not exceed
target levels.
Alternative SV4 would address soil vapor source material but would not provide protection from
residual risks until all source material is removed or has attenuated, which could continue to
provide a source for soil vapor migrating into indoor air at concentrations greater than PRGs.
Off-gas treatment would be included, if required to reduce the rate of COCs venting to the
atmosphere.
Alternative SV5 would address residual risk by implementing VIMS after soil vapor source
removal occurs. Residual COC concentrations remaining in the subsurface would be addressed
by natural attenuation. VIMS monitoring would be required to verify that COC concentrations do
not exceed target levels. Off-gas treatment from SVE would be included, if required to reduce
environmental impacts of COCs venting to the atmosphere.
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4. Reduction of Toxicity, Mobility, or Volume of Contaminants through Treatment
No active treatment processes would be used for Alternative SV1 and SV3; therefore, no
reduction of toxicity, mobility, or volume through treatment is anticipated. However, natural
attenuation processes and extraction from VIMS are expected to reduce COC concentrations in
indoor air, though not from treatment.
Alternatives SV4 and SV5 would include physical treatment using an SVE system to remove
contaminated soil vapors from the subsurface (potentially with off-gas treatment) and soil
excavation to remove contaminated soil. Therefore, both alternatives would meet the NCP
preference for treatment if the SVE includes off-gas treatment.
Alternatives SV4 and SV5 would both increase mobility of soil vapors during SVE, though the
mobile vapors would be directed towards the extraction wells and removed from the
environment. There would be the potential for residual contamination to remain in the subsurface
in areas where the radius of influence of vapor extraction wells is insufficient to remove all
contaminated soil vapors.
5. Short-term Effectiveness
There are no additional risks associated with Alternative SV1 because no remedial action would
be taken, and no construction would be performed. The remedial option with the greatest short-
term effectiveness is Alternative SV3. This option would have the least amount of construction
and work required. Alternatives SV4 and SV5 would provide the least degree of short-term
effectiveness because of the installation of the SVE system (vertical or horizontal extraction
points and potentially off-gas treatment) and soil excavation and offsite disposal activities. The
overall difference between Alternatives SV4 and SV5 would be that only Alternative SV5 would
require the installation of individual VIMS in multiple buildings so Alternative SV5 would be
effective in controlling exposures in the short term; whereas, SV4 would not. Exposure to
contaminated soil and soil vapor during construction would be controlled through standard best
management practices such as appropriate decontamination protocols, air monitoring, and
appropriate traffic control measures.
6. Implementability
Alternative SV1 would require no construction or treatment and would be the easiest to
implement. Alternative SV3 would only require the installation of VIMS with materials that are
readily available. Alternative SV4 would require the installation of an SVE system, soil
excavation, and offsite disposal of contaminated soil. Alternative SV5 would have the greatest
implementability challenges as it requires the most activities, including VIM and SVE system
installation, soil excavation, and offsite disposal of contaminated soils.
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7. Cost
An overview of the cost analysis performed for this evaluation and the detailed breakdowns for
each of the alternatives are presented in Appendix D of the FS report. Although the initial capital
cost for Alternative SV5 is significantly greater than Alternative SV3, Alternatives SV3 and SV5
have a similar overall present-values due to the longer timeframe required for O&M for
Alternative SV3 (30 years versus 5 years for Alternative SV5). Total costs are summarized as
follows:
Alternative SV1
Alternative SV4
Alternative SV3
Alternative SV5
$0
$3.34 million
$7.43 million
$7.54 million
8. State Agency Acceptance
IDEM supports the selected soil vapor remedy, Alternative SV5. EPA received a February 11,
2021 letter from the Assistant Commissioner of IDEM expressing concurrence with the selected
remedy (Appendix B).
9. Community Acceptance
During the virtual public meeting and public comment period, the community expressed support
for EPA's preferred soil vapor remedy, Alternative SV5. Further details can be found in the
Responsiveness Summary which is Part III of this ROD.
11.0 Principal Threat Waste
The NCP establishes an expectation that EPA will use treatment to address the principal threats
posed by a Site, wherever practical. The principal threat concept is applied to the characterization
of "source material" at a Superfund Site. Source material includes or contains hazardous
substances, pollutants or contaminants that act as a source for migration of contaminants to
groundwater, surface water or air, or acts as a source for direct exposure. EPA has defined
principal threat wastes as those source materials considered to be highly toxic or highly mobile
that generally cannot be reliably contained or would present a significant risk to human health or
the environment should exposure occur.
During the RI, EPA did not identify any principal threat waste on the Site. From 2005 through
2008, EPA oversaw a removal action at the former Master Wear facility on the Site, which
involved the cleanup of highly contaminated groundwater at concentrations indicative of the
presence of source material. Though EPA believes most, if not all, source material has been
depleted and that the groundwater and soil vapor contamination is residual contamination from
former source material, EPA will continue to investigate for the presence of source material,
particularly in this area, during the remedial design and possibly during the implementation of
the soil vapor remedy. The selected soil vapor alternative includes the potential for the removal
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and/or treatment of such source material through the use of soil excavations and/or soil vapor
extraction.
12.0 Selected Remedy
EPA has selected as the Site remedy the combination of Groundwater Alternative GW-2A
(GAC) to continue to protect the municipal drinking water supply; Groundwater Alternative
GW-5 (ISCR) to reduce concentrations in the central (greater than 46 |ig/L of PCE) portion of
the groundwater plume followed by MNA, and Soil Vapor Alternative SV-5 (Pathway Sealing,
VIMS, and Soil Vapor Source Removal) to both reduce soil vapor concentrations and protect
receptors from exposure to these vapors. EPA is also including as part of this remedy LTM of
groundwater and soil vapor, the implementation of ICs to protect from exposures to Site
contaminants until groundwater and soil vapor reach PRGs, and the connection of residential
properties to the municipal drinking water supply if EPA identifies any such properties relying
on private wells drawing from the Site groundwater plume for drinking water.
If EPA, in consultation with IDEM, determines during the design of the remedy that it is not
confident the risks posed by implementing ISCR can be sufficiently managed, EPA will instead
select ISCO. These risks are described in Section 10 above and include methanogenesis,
daughter product formation, as well as any other risks posed by converting a largely aerobic
aquifer to anaerobic conditions. Additionally, EPA may also change its groundwater remedy
selection to ISCO rather than ISCR if EPA and IDEM find ISCR to be insufficiently effective
after implementation. If EPA chooses to implement the contingent remedy, EPA will issue a
decision document to record this change in the remedial approach. IDEM will be given an
opportunity to comment on and concur with any potential change in remedy.
12.1 Summary of the Rationale for the Selected Remedy
The groundwater portion of the Selected Remedial Cleanup Alternative for the P&M Site is a
combination of Groundwater Alternatives GW2 (Option GW2A - GAC treatment at the City's
WTP) and GW5 (ISCR). EPA estimates that the total present value cost of the groundwater
portion of the remedy will be $4.38 million and that it will take between 9 and 17 years for the
Site groundwater to reach RAOs. This will include an initial period of active treatment followed
by a period of MNA.
The City, IDEM, and EPA are in agreement that continued use of GAC is the preferred treatment
option for the City's WTP (Option GW2A). The infrastructure is already in place and this
technology has proven to be effective at removing PCE from the City's drinking water supply.
Based on concerns raised by the City that some residential properties could be relying on a
private well located in the Site groundwater plume for drinking, EPA is also including in the
Selected Remedial Cleanup Alternative the option to connect residential properties to the City's
municipal drinking water supply.
In the FS, EPA determined that both ISCO (Groundwater Alternative GW6) and ISCR
(Groundwater Alternative GW5) have the potential to effectively reduce PCE in groundwater at
the Site but that ISCR has the potential to more effectively treat the groundwater plume because
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the reducing conditions produced by the ISCR treatment reagents could persist longer than the
ISCO reagent and stimulate continued biological reductive dechlorination of PCE. The ISCR
treatment reagents also pose less of a risk than the strong oxidants used for ISCO. However, EPA
also found that there are risks in converting a largely aerobic aquifer to reducing conditions. EPA
expects ISCR to include the addition of significant amounts of ZVI and a carbon source to create
and sustain anaerobic conditions by consuming oxygen and other electron acceptors during
biodegradation. In some situations, this can result in the unintended production of subsurface
methane (methanogenesis). Also, after the short-term chemically destructive treatment of PCE
by ZVI, longer-term anaerobic biodegradation of PCE can sometimes result in an accumulation
of daughter products, possibly with higher toxicity. For these reasons, EPA identified in the
proposed plan ISCO as its preferred remedial alternative for addressing groundwater
contamination.
After receiving numerous comments from the public, including the City of Martinsville,
supporting ISCR over ISCO, reviewing the current status of technologies available to control for
the unintended side effects of implementing ISCR in an aerobic aquifer (specifically,
methanogenesis and daughter product formation), and consulting with IDEM, EPA changed its
preference and is instead selecting ISCR as the groundwater treatment alternative for this Site.
However, EPA is making this selection contingent on a determination during the remedial design
that it can sufficiently mitigate the potential for methanogenesis and daughter product formation.
If EPA determines that it cannot sufficiently manage for the potential risks with ISCR
implementation or that ISCR is otherwise ineffective, EPA will instead implement ISCO for
treating groundwater. If EPA determines that such contingency needs to be implemented, it will
reflect this change in a decision document.
The soil vapor portion of the Selected Remedial Cleanup Alternative for the P&M Site is Soil
Vapor Alternative SV5 (Pathway Sealing, Soil Vapor Source Removal, VIMs). EPA estimates
that the total present value cost of this portion of the remedy will be $7.54 million; however, this
estimate required a number of assumptions regarding the number of houses to be sampled, the
number needing mitigation, and the results of design investigations. Also, this estimate included
the assumption that the VIMS would need to be operated for 30 years. The VIMS will need to
be operated until the groundwater and soil vapor concentrations are reduced to a level that no
longer pose a threat to human health via indoor air. EPA expects that it will take longer for
groundwater concentrations to reach RAOs than soil vapor concentrations to reach RAOs so
EPA believes 30 years is a conservatively high assumption.
Based on the comments received during the public comment period, the public and the City
concur with IDEM and EPA that soil vapor alternative SV5 is the preferred alternative for the
soil vapor portion of the remedy. This alternative is a combination of the other active soil vapor
treatment alternatives and represents the most aggressive treatment option evaluated. Soil vapor
concentrations will be reduced using SVE and, if necessary, soil excavation, and the human
health exposure pathway will be protected using a combination of pathway sealing and VIMs.
Based on the information available, the Selected Remedial Cleanup Alternative satisfies the
following statutory requirements of CERCLA 121(b): it is protective of human health and the
environment, complies with ARARs, is cost-effective, and utilizes permanent solutions and
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alternative treatment technologies to the maximum extent practicable. The Selected Remedial
Cleanup Alternative complies with the statutory preference for selecting a remedy that involves
treatment as a principal element.
12.2 Description of Remedial Components
The groundwater component of the Selected Remedial Cleanup Alternative includes ISCR in the
central portion (greater than 46 jj.g/1 of PCE) of the groundwater plume and MNA in the
remaining portions of the plume as well as in the central portion of the plume after active
treatment decreases concentrations to below 46 |ig/l17. ISCR involves injecting an insoluble
chemical amendment, such as ZVI with or without a carbon source, in solid or slurry form into
the groundwater plume. Under strongly reducing conditions ZVI chemically destroys PCE to
non-toxic end products while a carbon source will cause the PCE contamination in the
groundwater to breakdown through reductive dechlorination. EPA may utilize more than one
injection event to reduce concentrations in the central portion of the groundwater plume to a
level that will allow natural attenuation to achieve PRGs in a reasonable amount of time.
If EPA determines that the risks associated with ISCR cannot be adequately managed or ISCR
proves to be insufficiently effective, EPA will instead utilize ISCO for actively treating the
central portion of the groundwater plume. ISCO is similar to ISCR except that strongly
oxidizing conditions are created through the injection of oxidants such as potassium
permanganate. PCE would then be fully oxidized to CO2, water, and inorganic chloride without
producing more toxic intermediate daughter products.
To protect human health from exposure to the Site's groundwater contamination via the drinking
water pathway, the Selected Remedial Cleanup Alternative also includes continued treatment of
the City's municipal drinking water with GAC and, if necessary, connection of residential
properties at the Site to the City's municipal drinking water supply. The GAC treatment of the
City's municipal drinking water will continue until Site groundwater contamination is reduced to
below the PRG (the drinking water MCL for PCE of 5 |ig/L).
The soil vapor components of the Selected Remedial Cleanup Alternative include SVE in one or
more areas of relatively high soil vapor concentrations at the Site and will include soil
excavation if EPA identifies any soil contamination during the RD or RA that merits excavation.
To protect human health from exposures to PCE contamination in indoor air via the VI pathway,
the Selected Remedial Cleanup Alternative will also include a combination of monitoring and,
where necessary, mitigation using pathway sealing and VIMs.
The Selected Remedial Cleanup Alternative will also include implementation of ICs aimed at
preventing exposures to Site soil vapor and/or groundwater contamination until such
contamination is reduced to below the PRGs.
17 EPA expects to set the performance standard during the remedial design, but it will be no greater than 46 jxg/1.
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The Selected Remedial Cleanup Alternative also includes LTM of groundwater and soil vapor to
track the progress of active treatment and natural attenuation and to determine where ICs need to
be implemented. Long-term monitoring will continue until Site contaminants are reduced to
below PRGs.
12.3 Summary of the Estimated Remedy Costs
EPA estimates the present worth cost for the selected remedy is $11.92 million. The principal
elements of the remedy costs for each component of the remedy include capital cost, periodic
costs, and O&M, except that there are no capital costs associated with the GAC treatment at the
City's WTP. EPA estimates that the groundwater treatment component (ISCR followed by
MNA) will have a capital cost of $1.34 million, recurring O&M costs between $82,027 and
$404,907, and recurring periodic costs of $42,081. EPA estimates the treatment at the City's
WTP with GAC will have recurring O&M costs of $61,500 and recurring periodic costs of
$87,514. EPA estimates the soil vapor component (pathway sealing, soil vapor source removal,
and VIMs installation) will have a capital cost of $6.08 million, recurring O&M costs of
$304,150, and recurring periodic costs of $72,202.
Appendix D of the FS report for the Site contains more details supporting these cost estimates.
EPA further notes that these estimates are based on assumed findings during the RD and RA that
will affect the extent to which the remedial components will be implemented. In particular, the
number of structures requiring VIMs is largely unknown at this time, and the extent to which
EPA will implement soil vapor source removal could change upon further investigation.
12.4 Expected Outcomes of the Selected Remedy
The selected remedy will protect human health and the environment under current and
reasonably anticipated future property uses at the Site by continuing to treat groundwater at the
Site used for drinking water, providing access to treated groundwater, treating the groundwater
contaminant plume, identifying and preventing exposures to soil vapor contamination, treating
soil vapor contamination, and implementing ICs on affected land and groundwater use until
RAOs are achieved. Site monitoring combined with ICs will provide the ongoing data needed to
assess the progress of the selected remedy and ensure that new exposure pathways do not arise.
EPA estimates that RAOs for the groundwater will be achieved in 9 to 17 years and that RAOs
for soil vapor will be achieved upon successful implementation of vapor intrusion mitigation.
Installation of VIMs could typically be accomplished within the first year of construction, which
would achieve the soil vapor RAO initially by eliminating exposure to COCs in indoor air. Long-
term, the soil vapor RAO would be met by depleting the source through operation of an SVE
system (estimated to be 5 years) and through treatment of groundwater.
13.0 Statutory Determinations
Under CERCLA Section 121 and the NCP, the lead Agency must select remedies that are
protective of human health and the environment, attain federal and state requirements that are
applicable or relevant and appropriate for this remedial action (or invoke an appropriate waiver),
are cost effective, and utilize permanent solutions to the maximum extent practicable. In
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addition, CERCLA includes a preference for remedies that employ treatment that permanently
and significantly reduce the toxicity, mobility, or volume of hazardous wastes as a principal
element and a bias against off-site disposal of untreated wastes. The following sections discuss
how the selected remedy addresses these statutory requirements.
13.1 Protection of Human Health and the Environment
The selected remedy will be protective of human health and the environment for the risks
associated with the Site. ISCR, GAC treatment of the municipal water supply, ICs, and
monitoring will be protective of human health and the environment for groundwater risks.
Pathway sealing, VIMs, soil vapor source removal, and monitoring will be protective of human
health and the environment for soil vapor risks. ISCR will provide an initial reduction in the
portion of the groundwater plume with the highest contaminant concentrations, and MNA will
provide the opportunity to reach groundwater RAOs over the long-term. Soil vapor source
removal and groundwater treatment will provide the opportunity to reach soil vapor RAOs.
Implementation of ICs will provide restrictions to protect human health, the environment, and
the remedy, as needed. Monitoring will track the remedy so EPA can ensure that the remedy
achieves the RAOs.
13.2 Compliance with ARARs
The selected remedy is expected to comply with the state and federal ARARs that are specific to
the scope of this remedy action. The ARARs for this remedial action are discussed in Sections
10.1 and 10.2 above.
13.3 Cost-effectiveness
EPA has determined that the selected remedy is cost effective, will be protective and represents a
reasonable level of protectiveness for the money to be spent. In making this determination, the
following definition was used: "[a] remedy shall be cost effective if its costs are proportional to
the overall effectiveness." (40 C.F.R. 300.430(f)(l)(ii)(D)). "Overall effectiveness" was
evaluated by assessing three of the five balancing criteria (long term effectiveness and
permanence, reduction of toxicity, mobility or volume through treatment, and short-term
effectiveness). Overall effectiveness was then compared to cost to determine cost-effectiveness.
The relationship to the overall effectiveness of this remedial action was determined to be
proportional to its costs; therefore, the remedy represents a reasonable level of protectiveness for
the money spent. The estimated present worth of the selected remedy is $11.92 million.
13.4 Utilization of Permanent Solutions and Alternative Treatment Technologies
(or Resource Recovery Technologies) to the Maximum Extent Practicable
EPA has determined that the selected remedy represents the maximum extent to which
permanent solutions and treatment technologies can be utilized in a practicable manner at the
Site. Of those alternatives that are protective of human health and the environment and comply
with ARARs, EPA has determined that the selected remedy provides the best balance of trade-
offs in terms of the five balancing criteria, while also considering the preference for treatment as
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a principal element, the bias against off-site treatment and disposal, and state and community
acceptance.
The selected remedy, Groundwater Alternatives GW2A and GW5 and Soil Vapor Alternative
SV5, achieves substantial risk and mass reduction. In-situ treatment of the central portion of the
groundwater plume as well as natural attenuation will permanently reduce the mass of Site
groundwater contamination and, thus, reduce risk. The end goal of the chemical reduction
process is to convert PCE into non-toxic end products. Continued treatment at the City's WTP
using GAC as well as connection to the municipal drinking water system of any residential
properties at the Site currently dependent on private wells will substantially reduce risk from
exposure to contaminated groundwater at the Site. Soil vapor source removal and groundwater
treatment will permanently reduce the mass of Site soil vapor contamination and, thus, reduce
risk. Pathway sealing and the installation of VIMs will substantially reduce risk from exposure to
Site soil vapor contamination.
13.5 Preference for Treatment as a Principal Element
By treating the highest concentrations of Site groundwater contamination with ISCR and
reducing soil vapor contamination with source removal involving soil vapor extraction, the
selected remedy satisfies the statutory preference for remedies that employ treatment as a
principal element.
13.6 Five-Year Review Requirements
CERCLA § 121(c) and the NCP § 300.430(f)(5)(iii)(C) provide the statutory and legal bases for
conducting Five-Year Reviews. Until RAOs are achieved, hazardous substances will remain at
the Site in the groundwater above levels that allow for UU/UE. As a result, statutory reviews will
be conducted every five years after commencement of the remedial action to ensure that the
remedy is, or will be, protective of human health and the environment until the RAOs are
achieved.
14.0 Documentation of Significant Changes
The Proposed Plan for this Site identified a combination of Groundwater Alternative GW-2A
(GAC), Groundwater Alternative GW-6 (ISCO), and Soil Vapor Alternative SV-5 (Pathway
Sealing, Vapor Intrusion Mitigation, and Soil Vapor Source Removal) as the preferred remedial
action. In this ROD, EPA has selected Groundwater Alternative GW-5 (ISCR) instead of
Groundwater Alternative GW-6 (ISCO), while retaining Groundwater Alternative GW-6 (ISCO)
as a contingent alternative to Groundwater Alternative GW-5 (ISCR).
The Proposed Plan comment period ran from August 3, 2020 to October 3, 2020. CERCLA
Section 117(b) and the NCP at 300.430(f)(5)(iii) requires an explanation of significant changes
from the remedy presented in the Proposed Plan that was published for public comment. After
receipt of numerous comments supporting the selection of Groundwater Alternative GW-5
(ISCR) instead of Groundwater Alternative GW-6 (ISCO), EPA reconsidered its proposal to
select Groundwater Alternative GW-6 (ISCO).
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EPA proposed Groundwater Alternative GW-6 (ISCO) instead of Groundwater Alternative GW-
5 because of the potential risks posed by the implementation of ISCR. However, EPA
recognizes that ISCR may be a more effective than ISCO for treating the Site's groundwater
contamination and options may be available to adequately manage the risks posed by ISCR. As
such, EPA is making this significant change from the proposed plan but is retaining as a
contingency the option to implement ISCO instead of ISCR if EPA determines these risks cannot
be sufficiently managed. EPA is also retaining the option of implementing ISCO if the initial
implementation of ISCR proves to be insufficiently effective. If EPA chooses to implement this
contingency, EPA will issue a decision document to record this change in the remedial approach.
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Part III: Responsiveness Summary
This Responsiveness Summary documents public participation in the remedy selection process
for the P&M Site. A summary of comments received during the 60-day public comment period
and during the August 12, 2020 virtual public meeting are included in this section of the ROD,
along with EPA's responses to these comments. The public comment period for this response
action ran from August 3, 2020 to October 3, 2020.
1) Several commenters pointed out that the FS report used the term "highly effective" when
describing the potential effectiveness of ISCR and "moderately effective" when
describing ISCO and expressed support for the use of ISCR versus ISCO.
EPA response: EPA notes that the use of these terms could be misleading. The
difference in terminology is based on the fact that ISCR treatment materials are expected
to persist in the aquifer longer than ISCO. The overall effectiveness of the treatment can
also be affected by how well the injected materials can be distributed through the aquifer
and the number of injection events. Either of these in situ treatments could effectively
treat the groundwater contamination.
EPA proposed ISCO versus ISCR because there is less chance of unintended
consequences when adding oxidants to an already aerobic (oxidizing) aquifer. ISCR
requires a change in the fundamental chemistry of the aquifer to anaerobic (reducing)
conditions. As such, EPA predicts that there is a greater risk in using ISCR, though these
risks may indeed be manageable.
In this ROD, EPA is selecting ISCR with the option of using ISCO instead. Specifically,
EPA plans to evaluate the potential risks posed by ISCR and determine if these risks can
be adequately managed. If EPA does not feel these risks can be adequately managed,
EPA will instead use ISCO. If EPA opts to use ISCO, the change will be documented in a
subsequent decision document.
2) One commenter asked what the vapor intrusion sampling and installation of a mitigation
system costs a property owner. Another commenter asked if owners of properties
equipped with VIMS would be compensated for the cost to operate the fans that are part
of these systems.
EPA Response: There is no cost to property owners to have EPA sample their home or
business for vapor intrusion. Similarly, there is no cost to property owners for the
installation of a mitigation system where these may be needed. However, EPA cannot
reimburse property owners for the added energy costs to operate these fans as these are
operation and maintenance costs - which EPA is statutorily limited from paying. The
wattage of the fans used for VIMs varies, depending on the size of the structure, and are
typically in the range of 150 Watts so the electricity costs to run this system are
equivalent to the costs to leave on two 75 Watt incandescent lightbulbs.
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One commenter expressed concern about depressed property values as a result of the site
being included on the National Priority's List (i.e. making it a "Superfund" site).
EPA Response: EPA is unable to control real estate market conditions as a result of a
site becoming a Superfund site. However, EPA can work to improve site conditions, and
provide property owners with data to demonstrate the site is not impacting their property
or that the impacts have been mitigated.
EPA evaluated the issue of the impact of Superfund Sites on property values in the
following publication:
https://semspub.epa.gov/work/05/927384.pdf
In addition, EPA further evaluated the economic impacts of its clean-up work in the
following handbook:
https://www.epa.gov/environmental-economics/handbook-benefits-costs-and-impacts-
1 and-cl eanup -and-reuse
One commenter representing a local environmental group asked how many properties
were above the plume and if those properties could be identified.
EPA Response: During the investigation, EPA identified approximately 230 properties
above the soil vapor plumes associated with the Site. The soil vapor plumes are
delineated on maps located in the RI Report (Figures 5-7 and 5-8) and the FS Report
(Figures 1-12 and 1-13).
One or more commenters asked when EPA would be conducting additional vapor
intrusion sampling.
EPA Response: EPA expects that it will begin collecting additional vapor intrusion
samples within approximately one year of issuing this ROD. After issuing the ROD,
EPA will need to procure a contractor, approve the necessary sampling and quality
assurance plans, and obtain written access from property owners before it can begin
taking additional vapor intrusion samples.
One or more commenters have asked about the operation and or disposition of equipment
leftover from previous EPA response activities at the site.
EPA Response: Any property owners with leftover equipment at their property should
contact EPA. EPA does not recommend discontinuing the operation of any equipment
(such as a vapor intrusion mitigation system, as one commenter alluded to) until more
information can be obtained.
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7) One or more commenters asked about what vapor intrusion sampling is and how long it
takes.
EPA Response: Vapor intrusion sampling at a building typically involves performing a
building survey, collecting sub-slab vapor or crawlspace air and indoor air samples. Sub-
slab vapor is the "air" in the soil beneath the building slab, and crawlspace air is the air
within the crawlspace beneath the building. Vapor intrusion sampling is typically
performed over two or three days, but the work only takes an hour or two each day. The
sampling requires little-to-no involvement from the property owner or resident, aside
from setting up appointments allowing the sampling team inside the property. The
following description reflects what EPA expects to be the VI sampling procedures to be
conducted in the future at the Site:
The building survey and sub-slab probe installation are performed on the first day
(approximately two hours of work). The sampling team will take notes on the building
construction and occupancy conditions. They will ask the property owner/occupant
questions to gather this information. The sampling team will also use a hand-held
detector to identify any potential indoor sources of volatile organic compounds (VOCs)
(such as solvents, cleaning products or craft glues) that may interfere with the samples.
Any indoor VOC sources identified, such as certain cleaning or degreasing products, will
be placed outside of the building in a storage bin for the next two days while the samples
are collected. If the building is constructed on a slab, then one or more sub-slab probes
(depending on the building size) will be installed by drilling a small hole (approximately
1.5-inch diameter) through the slab with a hammer drill.
Collection of the indoor air samples will begin on the second day (approximately 1 hour
of work). Also, if the building is constructed on a full or partial crawlspace, then
crawlspace air samples will also be collected. The indoor and crawlspace air samples are
collected in stainless-steel canisters (approximately the size and shape of a basketball)
equipped with flow controllers so that the samples will collect over an 8- or 24-hour
period (depending on building occupancy - 8 hours for commercial buildings and 24
hours for residential buildings). The canisters should not be touched or moved around the
property. The indoor and crawlspace air samples will be collected the same day at
commercial buildings.
The indoor and crawlspace air (for residential buildings) and sub-slab vapor samples will
be collected on the third day (approximately 2 hours of work). The indoor and crawlspace
air canisters will be collected from the building, and then the sub-slab probes will be
sampled. The sampling team will connect tubing and a smaller stainless-steel canister to
the sub-slab probes and collect the sample. The sub-slab probes will be covered with a
small metal plate (size of a half dollar coin) and left in place so that they can be sampled
again in the future if necessary.
8) A number of commenters expressed support for the use of sorptive-reactive media, citing
a specific product used at a neighboring state-led site.
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EPA Response: EPA evaluated the use of sorptive-reactive media in the FS (Alternative
GW-7) and screened this clean-up option out due to its limited history of use and the
limited data demonstrating its effectiveness. Because it received numerous comments
supporting the use of this technology, EPA conducted a supplemental evaluation of this
technology for consideration at this site.
Sorptive-reactive media by itself only adsorbs the contamination; however, typical
applications will include treatment additives designed to break down or otherwise destroy
the contamination. These additives, such as those that might be used for ISCR or ISCO,
could be added without the sorbent materials. The primary benefit of the sorbent
materials is it reduces the mobility of the contamination. At this site, EPA does not see
mobility reduction as a primary concern for treatment as it will take many years for the
elevated groundwater contamination in the treatment area to reach the City's municipal
wellfield.
In addition, EPA remains concerned that data demonstrating that the contaminants are
broken down by the intended mechanism is still limited. Data demonstrating that
groundwater contaminant concentrations are lower downgradient of the sorbent material
are not an indicator that the contamination has been fully degraded, only that the
contaminants have been adsorbed to the sorbent material.
EPA is also concerned about the practicality of applying this technology throughout the
entire portion of the plume it intends to treat.
9) One or more commenters asked about private drinking water wells located within the
groundwater plume.
EPA Response: EPA made efforts to identify any private drinking water wells within
the vicinity of the groundwater plume. EPA identified three private drinking water wells
near the plume and was able to sample each well. None of the wells were found to have
contaminants above EPA's drinking water standard.
Regardless, EPA has included an option in the ROD to connect to municipal water any
existing residential properties dependent on a private drinking water well drawing water
from the Site groundwater plume.
EPA encourages any owners of property in the vicinity of the plume using a private
drinking water well to contact EPA or IDEM as soon as possible. Furthermore, EPA
strongly discourages the use of these wells for potable purposes, unless the well is outside
of the plume. However, even then, EPA encourages property owners to arrange to have
their wells tested for VOCs. The Site plume is not the only known groundwater
contamination in Martinsville.
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10) One commenter asked about institutional controls that EPA would look to the City to
implement.
EPA Response: Institutional controls are legal controls EPA puts in place or arranges to
have put in place to prevent exposures to Site contaminants until clean-up levels can be
met. One type of institutional control that EPA may try to utilize is referred to as
"governmental controls." This includes legal restrictions, such as a local ordinance, that
would prevent exposure to Site contaminants. At this stage, it is too early to determine
the specific institutional controls that EPA may utilize to prevent exposures. However, it
is conceivable that EPA might request that the City implement a local ordinance
restricting the use of drinking water wells in the vicinity of the groundwater plume.
11) One commenter asked about where EPA expects to remove contaminated soils.
EPA Response: During the RI, EPA only identified a small area of soil contamination
(near the former Master Wear facility). EPA plans to conduct pre-design investigations
to determine if limited removal of soil contamination is warranted. EPA expects that, if
needed, soil removal activities will be very small in scale.
12) One commenter asked about remedial activities and redevelopment activities in the area
interfering with each other.
EPA Response: EPA doesn't expect to begin remedial activities for at least a year. At
that time, EPA will work with city officials and others to minimize disruption from
remedial activities. EPA recommends that developers be made aware of Site
contamination and take proper precautions in the design and implementation of
development activities to prevent exposures from Site contaminants at depth.
13) One commenter asked about the use of monitored natural attenuation as part of the
proposed remedy.
EPA Response: EPA proposed and is now selecting an active groundwater treatment
remedy in the central portion of the groundwater plume with PCE concentrations greater
than 46 ppb while depending on natural attenuation to reduce the other, lower
concentration portions of the plume to below clean-up levels. EPA will monitor the rate
at which these natural processes attenuate contaminant concentrations and may choose to
actively treat these areas at a later time if deemed necessary to meet clean-up levels in a
reasonable amount of time.
14) One commenter asked about the area in which EPA expects to conduct future
investigations on individual properties.
EPA Response: EPA has provided maps in both the RI and FS reports that show the
total area of groundwater contamination as well as the total area of soil vapor
contamination as assessed during the RI. EPA typically extends its vapor intrusion
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investigations to homes and businesses inside of or within 100 feet of the soil vapor
contamination area. EPA will consider sampling or otherwise addressing any private
drinking water wells within or in close proximity to the groundwater plume.
EPA notes that the delineation of the groundwater and soil vapor plumes might change as
it gathers additional data going forward.
15) Several commenters discussed the expected timeframe for the cleanup.
EPA Response: In the proposed plan, EPA discussed one estimate developed during the
FS that showed that treating the central portion of the plume with ISCO combined with
MNA for the lower-concentration periphery of the plume would take fifteen years before
the groundwater meets clean-up levels (i.e. the Federal drinking water standard for PCE
of 5 parts per billion). This estimate was generated using models but required some
assumptions that over-simplify the number of potential variables that could affect this
rate. In comparison, for this particular scenario, EPA estimated that ISCR and MNA
would take 17 years to achieve MCLs throughout the plume.
Regardless of the set of assumptions used for preparing these estimates, the actual rate at
which the groundwater will be cleaned up to the Federal drinking water standard is less
affected by the use of ISCR versus ISCO and more affected by how quickly treatment
can begin and how well the remediation reagent can be distributed in the subsurface.
An assumption in the model is for active treatment using ISCO or ISCR to take an
estimated 4 and 6 years, respectively. This time period allows for an initial treatment
event followed by an evaluation period of groundwater monitoring and a second injection
event, if warranted. The model assumes that after 4 or 6 years, contaminant
concentrations in groundwater would decrease from a maximum PCE concentration of
210 parts per billion to below the proposed treatment goal of 46 parts per billion. The full
duration of 15 to 17 years to achieve the Federal drinking water standard for PCE of 5
parts per billion is based on natural processes that passively occur after active treatment,
periodically monitored by sampling groundwater. Depending on the actual performance
results of the active groundwater treatment, which can be influenced by many factors, the
overall duration to achieve the Federal drinking water standard may be shorter. For
example, assuming active treatment decreases PCE concentrations to 16 parts per billion
results in overall durations of 11 and 9 years for ISCR and ISCO, respectively18.
16) One commenter asked about whether a number of contaminants were found at Site.
EPA Response: EPA only identified PCE as a contaminant of concern in groundwater at
the Site. However, EPA identified both PCE and TCE as contaminants of concern in soil
vapor at the Site. EPA did not identify any other contaminants of concern at the Site.
18 Note that an error was made in the FS report reversing these duration estimates. This error has been corrected and
the corrected version of the FS report for the Site is available on the website for the Site.
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17) One commenter asked about several other potential sources of contamination in the
Martinsville area.
EPA Response: EPA's Superfund Program is specifically tasked with investigating and
cleaning up the Pike and Mulberry Streets PCE Plume Site, which is defined as a
chlorinated solvent groundwater plume and associated areas of soil vapor contamination
generally centralized near the intersection of Pike and Mulberry Streets and extending to
the City's municipal wellfield. Concerns with other sources of contamination outside of
this area can be brought to the attention of the Indiana Department of Environmental
Management. In addition, EPA and IDEM welcome any information regarding parties
that are potentially responsible for the contamination.
18) One commenter asked: "Regarding the proposed potassium permanganate wax cylinders,
how will lateral distribution, perpendicular to groundwater flow be controlled to ensure
complete coverage across the treatment area?"
EPA Response: Though EPA is selecting ISCR in this ROD, EPA would determine
details such as this during the remedial design. Over time, technologies offered by
various suppliers and manufacturers may change. During the design phase, the best
available technologies at that time for chemical distribution will be reviewed and
considered. In the Proposed Plan, EPA had not proposed a specific type of oxidant nor a
vehicle for distributing an oxidant.
19) One commenter asked what the rationale is behind a 17-year post injection treatment
period of ISCR versus a 15-yr treatment period for ISCO. ISCR is generally known to
last longer within the subsurface.
EPA Response: Details about the modeling EPA completed for the estimates of
treatment times to reach RAOs can be found in Appendix E of the FS Report. The
commenter is referring to the Scenario 2 set of assumptions, which included a presumed
4-year treatment period for ISCO and a 6-year treatment period for ISCR. Scenario 2
assumes that concentrations are reduced through active treatment to below the treatment
goal of 46 parts per billion. While it is generally true that ISCR may last longer in the
subsurface, some long-lasting oxidants are also available. Additionally, ISCO typically
relies on faster reactions, which may reduce concentrations more quickly, compared to
ISCR.
EPA notes that under the Scenario 3 set of assumptions, which assumes that active
treatment is able to reduce concentrations by 90 percent, the overall timeframes decrease
to 11 and 9 years for ISCR and ISCO, respectively. EPA notes that these estimates are
based on a number of assumptions and cautions against placing too much emphasis on
these relatively small differences in time estimates.
20) One commenter asked why the estimated combined costs for GW-5 were less than those
for GW-6 but that estimated total present value for GW-5 is higher than that for GW-6?
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EPA Response: Details about these cost estimates can be found in Appendix D of the
FS Report. The differences between total combined costs and the total present value had
to do with the timing of when the costs are expected to occur and the discount rate (e.g.
costs incurred 10 years from now are of less value than if they were incurred today).
Additionally, the estimated timeframe for remediation for GW-5 is 17 years, while the
estimated timeframe for remediation of GW-6 is 15 years. This means that GW-5
includes two additional years of sampling and monitoring costs.
21) One commenter asked why more aggressive measures aren't being proposed to be taken
downgradient of "the source" now to address potential exposure of the residents and
businesses in the area. The commenter went on further to recommend the use of a
specific product that is a type of sorptive-reactive media and is being used for another
groundwater cleanup in the City of Martinsville.
EPA Response: First, EPA notes that it has not identified an ongoing "source" of
groundwater contamination. EPA oversaw remediation of what was known to be the
source as part of a time-critical removal action (TCRA) between 2003 and 2008. Prior to
the initiation of the TCRA, the PCE groundwater concentrations were as high as 31,000
parts per billion. During the TCRA, active remediation of the source was conducted using
a treatment system (details are provided in Appendix A of the FS report). The maximum
PCE concentration observed in groundwater during the remedial investigation activities
(2015 through 2017) was 210 parts per billion. A large portion of the remaining plume is
fairly diffuse (5 to 25 parts per billion) and spread over a large area (the total plume
length is over V2 mile long). Active treatment of these low concentrations over this entire
area is impractical.
EPA's proposed treatment plan includes active treatment in the most concentrated portion
of the remaining groundwater plume, followed by natural attenuation, as well as natural
attenuation in the remaining, lower concentration portions of the plume. EPA notes that
the ongoing GAC treatment of the municipal drinking water is preventing exposure to the
groundwater contamination from the use of the City's municipal water.
Regarding the use of sorptive-reactive media, see response to Comment 8 above.
22) One commenter, a vendor for a type of sorptive-reactive media, asked how quickly ISCO
will clean up a long, diffused plume and what is the expected longevity of the ISCO
reagent. The commenter went on to suggest the use of sorptive-reactive media.
EPA Response: The estimates for achieving Remedial Action Objectives (RAOs) can be
found in the FS Report, with specific details about how these estimates were generated
provided in Appendix E of the FS Report. EPA notes that it is now selecting ISCR in this
ROD, though it may invoke a contingency to use ISCO instead. EPA will select the
specific reagent(s) to be used during the remedial design. The low total oxidant demand
(TOD) results for the site (Table 3-4 of the FS) reflect low quantities of organic matter in
the sandy aquifer. As a result, an appropriate oxidant dose could remain reactive for 6
months to over a year, which is typical for applications in sandy aquifers. The oxidant
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longevity is site-specific and dose-specific and will not be known until applied in the
field.
Regarding the use of sorptive-reactive media, see response to Comment 8 above.
23) One commenter asked if EPA looked for 1,4-dioxane during its investigation noting that
it can be found as a comingled contaminant at chlorinated sites (most often with TCA,
but PCE/TCE as well).
EPA Response: EPA sampled for 1,4-dioxane during the RI but did not detect any. The
relevant data can be found in the groundwater data in Appendix A of the RI report.
24) One commenter, a vendor of ISCO technologies, stated support for EPA not specifying
an ISCO chemical and further encouraged including flexibility in the ROD as several
oxidants can effectively treat TCE/PCE and the final decision often comes down to cost.
EPA Response: This comment is noted, particularly if EPA uses the contingency to
employ ISCO technology as opposed to its selected remedy (ISCR). Also see response to
Comment 18 above.
25) One commenter, a vendor of ISCO technologies, suggested that we consider lower
solubility oxidants such as potassium persulfate as they would have the ability to persist
longer in the treatment area.
EPA Response: This comment is noted, particularly if EPA uses the contingency to
employ ISCO technology as opposed to its selected remedy (ISCR).
26) One commenter asked how decisions on the preferred clean-up method will be affected
by new information received during the clean-up period.
EPA Response: EPA will continue to evaluate the remedy during the remedial design
and throughout implementation of the remedial action. Furthermore, EPA will continue
to evaluate the remedy until the RAOs are achieved. This will include a comprehensive
review of the Site every 5 years until the Site is cleaned up.
27) One commenter asked how EPA will work with local government to ensure that no one
puts a well in the affected area or builds a day care or pre-school in the affected area.
EPA Response: EPA was recently made aware of an ordinance implemented by the City
to prevent installation of new wells within the groundwater plume. Provided that a day
care or pre-school is not using a private well and that the structure is monitored for indoor
air impacts from VI (and mitigated if necessary), there is no additional risk to these types
of facilities being operated in the vicinity of the Site.
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EPA may also work with local government to implement requirements for new
construction in the vicinity of the Site, or portions of the Site, to be equipped with vapor
mitigation, barriers, or the like.
28) One commenter asked how future residents, property owners, or business owners will be
made aware of the Site and further asked if this information is required during real estate
transactions.
EPA Response: EPA will continue community engagement activities throughout design
and implementation of the remedy. A copy of the Administrative Record will be added
to the repository at the Morgan County Library and on EPA's web site for the
Site. Though EPA may use informational devices such as deed notices at specific
properties, EPA does not have a mechanism for identifying and notifying all prospective
purchasers of properties within the vicinity of the Site.
EPA also notes that some states have disclosure laws that require owners to report
pollution problems to buyers when they sell a property, but these laws are outside of
EPA's jurisdiction. For further information, EPA recommends contacting a real estate
representative, state and/or local government agencies, or an attorney.
29) Several commenters inquired about past exposures leading to health issues.
EPA Response: The federal Agency for Toxic Substances and Disease Registry issued a
report in 2020 concluding that people's health is not likely to be harmed by Site
contaminants in the municipal drinking water supply, both in the past and currently. The
document is available here:
https://www.atsdr.cdc.gOv/HA.C/pha/PikeMiilberrvStreetsPCEPliime/Pike_MulbeiTvStrts
PCE Plume HC-508.pdf
If you have any questions about this report or other health concerns, you may contact the
author, Dr. Motria Caudill, at 312-886-0267 or mcaudill@cdc.gov.
30) One commenter pointed out that EPA's fact sheet for the proposed plan described
breaking down site contaminants into "less toxic" constituents and stated that EPA's goal
should be to break down contaminants into non-toxic constituents.
EPA Response: EPA notes that, while true, referring to the breakdown products as less
toxic could lead a reader to believe that these products still pose a risk. To be clear,
EPA's goal for this remedial action is to remove contamination, in the case of soil vapor,
and to break down contamination into non-toxic constituents, in the case of groundwater.
31) One commenter asked whether the PRG for PCE in groundwater (the MCL of 5 |ig/l) is
meant for the groundwater before it is treated at the City's municipal drinking water plant
or after.
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EPA Response: EPA's Remedial Action Objective to restore to beneficial use the
aquifer in which the Site's groundwater plume is located requires EPA to clean up the
groundwater in the aquifer to below the MCL (i.e. before treatment). Treatment of the
City's drinking water with GAC is necessary to meet EPA's RAO to prevent exposures to
contaminated groundwater through the drinking water pathway before the aquifer
achieves cleanup to the MCL.
32) One commenter asked about the timeframe for long-term monitoring of groundwater and
soil vapor.
EPA Response: EPA will continue monitoring groundwater and soil vapor until
contaminant levels are below PRGs. Furthermore, EPA will only discontinue monitoring
after it has determined, in consultation with IDEM, that contaminant levels have
consistently remained below PRGs that there is no concern for rebound or other changing
conditions causing concentrations to exceed PRGs.
33) One commenter asked which properties would receive ICs and about compensation for
ICs placed on deeds for these properties.
EPA Response: There is no list of properties for which EPA anticipates pursuing ICs,
particularly of the proprietary nature. Were EPA to acquire a property interest via a
proprietary IC, compensation may be necessary. There are hundreds of residences and
businesses located in the footprint of the groundwater plume and VI plume. Additionally,
there have been hazardous substances releases in other parts of Martinsville. EPA does
not believe proprietary controls are the most efficient means to prevent use of the aquifer
for potable purposes (i.e., by way of a private well) and to prevent harm from vapor
intrusion. EPA's preference is that ICs of a governmental nature be enacted.
34) One commenter asked about who would be responsible for the operation, maintenance,
and monitoring of the VIMS.
EPA Response: IDEM will primarily be responsible for maintaining the VIMS until Site
contamination has been reduced such that VI no longer poses a threat to human health at
the Site (or, in some cases, for that specific property).
35) One commenter asked if the City would be reimbursed for its costs to replace the GAC
filters at its drinking water plant while EPA has conducted its investigation and prepared
its decision and who would be paying to maintain the GAC filters in the future.
EPA Response: EPA is not a responsible party but is tasked with cleaning up and
preventing exposures to the contamination at the Site. As such, EPA will not be
reimbursing the City for past costs incurred to operate its GAC filter. EPA is
incorporating the GAC treatment into the remedial action selected by this ROD because it
finds that the GAC is necessary to prevent exposures to the Site's contaminated
groundwater until the groundwater can be cleaned up to below PRGs. Please see the
66
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response to question 40n. below for further information regarding costs associated with
the GAC systems.
36) One commenter asked what PRG applies to indoor air.
EPA Response: EPA assesses the need for a VIMS based on the concentrations of Site
contaminants in the soil vapor underneath (sub-slab) an occupied structure as well as the
concentrations of Site contaminants in indoor air.
A VIMS is installed to prevent soil vapors from accumulating in the indoor air, not to
treat the contamination or otherwise meet a clean-up goal. EPA is selecting soil vapor
source removal to reduce Site soil vapor concentrations to below PRGs. The PRGs for
soil vapor are based on levels which, when found in sub-slab vapors, do not pose a
potential health risk through inhalation of indoor air. These PRGs are listed in Section
8.0 of the ROD.
37) One commenter asked about any sort of guarantee of future funding for the cleanup of the
Site.
EPA Response: EPA cannot provide a funding guarantee; however, funding for
performance of the remedial action, operations and maintenance, and long-term
monitoring requirements will be planned to provide continuity of work. In addition, the
State of Indiana will also have cost-share responsibilities for long-term response actions.
38) One commenter asked whom at IDEM would EPA be working with to finalize this
decision.
EPA Response: EPA received concurrence on the remedy selected in the ROD from the
Assistant Commissioner of IDEM on February 11, 2021.
39) The City of Martinsville submitted comments to the proposed plan expressing support for
the selection of Soil Vapor Alternative SV5 and Groundwater Alternatives GW2A, GW5
(ISCR), and GW7 (sorptive-reactive media).
EPA Response: See EPA's Response to Comment #8 above regarding sorptive-reactive
media. Though EPA may elect to include some sorbent material with the mixture of
reagents injected as part of the ISCR treatment, EPA does not believe that the use of a
sorptive-reactive media is necessary to reduce exposures to contamination. Additionally,
EPA has concerns regarding solely relying on sorptive-reactive media to achieve PRGs
based on its limited history of use and the limited data demonstrating its effectiveness.
Data are still limited that demonstrate that the contaminants are broken down by the
intended mechanism, rather than just adsorbed to the medium.
In fact, the addition of sorbent material into the aquifer may make it more difficult for
EPA to sufficiently monitor the progress of the clean-up as it would be difficult to sample
and quantify the amount of sorbed contamination remaining in the aquifer. Data
67
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demonstrating that groundwater contaminant concentrations are lower downgradient of
the sorbent material are not an indicator of the ultimate fate of the contaminants, only that
the contaminants have been adsorbed to the sorbent material. The sorbed contaminants, if
not adequately degraded over time, may then later desorb back into the aquifer as the
sorptive-reactive media weathers or disintegrates in situ.
40) In its comments submitted during the public comment period, the City of Martinsville
asked the questions detailed below and followed by EPA responses:
a) When will the final ROD be issued?
EPA response: This responsiveness summary is part of the final ROD. EPA has
been in communication with the City of Martinsville throughout this process,
including discussions of the expected timeframes.
b) Will there be any more opportunity for input prior to or after release of the ROD?
EPA Response: EPA will continue to inform the City and its residents and workers
of any significant progress updates. EPA is also assisting in the formation of a
Community Advisory Group to facilitate the distribution and understanding of these
updates and to otherwise facilitate communication between these groups and EPA.
In addition, EPA seeks comment from the community when it conducts five-year
reviews, every five years after the remedial action begins. These reviews continue
until clean-up goals are met and the contamination no longer restricts any activities at
the Site.
c) When will the remedial design start?
EPA response: Because EPA has not identified any liable and viable responsible
parties for this Site, EPA assumes it will continue to lead the work. After the ROD is
finalized, EPA will procure a contractor to conduct the remedial design. Currently,
EPA expects that remedial design activities will begin in the fall of 2021.
d) When will pre-design investigations/testing start?
EPA response: Any pre-design investigations or testing will be part of the remedial
design contract.
e) When is the actual remedial action estimated to start?
EPA response: Assuming it continues to lead the work, EPA will seek to procure a
contractor to conduct the remedial action after it has finalized a remedial design. The
remedial design could take a year or more and some of the work may be limited to
particular seasons. EPA currently estimates that the groundwater and soil vapor
remedial activities will start after the remedial design is completed and funding is
68
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available for this remedial action, anticipated to be no sooner than 2023. EPA will
keep the City and the community up to date on the project schedule.
When will VI testing start?
EPA response: EPA hopes to re-start VI sampling early in the remedial design. The
specific timing depends on contract acquisition.
Will there be other properties sampled for VI beyond the initial approximately 230
EPA identified during the remedial design?
EPA response: While EPA expects to utilize the soil vapor investigation from the RI
in determining where to sample for potential VI exposures, EPA may supplement or
otherwise modify this list based on pre-design findings or other data generated
throughout the remedial design and/or remedial action.
Can people within the Pike and Mulberry Plume footprint request VI testing, even if
their property is not one of the buildings targeted for testing?
EPA response: While EPA may make some property-specific decisions about
whether to sample for VI or not, EPA generally expects to use the delineation of the
soil vapor plume in the RI for determining what properties to sample for VI.
How quickly will respective parties be notified of VI results?
EPA response: EPA endeavors to provide actual sampling data to property owners
as expeditiously as possible. Typically, results can be expected within one to two
months of the sampling.
What additional efforts will be made to identify private wells?
EPA response: EPA conducted efforts to identify private wells during the RI. While
EPA encourages property owners with private wells to discuss this with the City,
EPA, and/or IDEM; EPA does not have a specific plan for identifying additional
wells beyond community outreach activities.
Will these private wells be tested and will the (three) tested wells be retested?
EPA response: EPA may, in the future, elect to test private wells in or near the
Site's groundwater plume. However, to date, EPA identified only three private wells
in or near the Site's groundwater plume, and each of these wells were found to have
not been impacted by the Site's groundwater contamination.
Will the groundwater preliminary remedial goal of 5 |ig/l be in the ROD?
69
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EPA Response: Yes, EPA is selecting 5 jj.g/1, which is the MCL for PCE, as the a
PRG for PCE in groundwater.
Will ambient air be tested in the highly concentrated area of the plume?
EPA Response: While ambient air samples are typically part of EPA's VI sampling
protocol, these samples are conducted to determine the impact of background air from
non-Site related sources on Site sampling data. While EPA is concerned that soil
vapor contamination from the Site may be accumulating at harmful concentrations in
indoor air, EPA is not concerned about exposures in ambient (outside) air from soil
vapor or groundwater contamination. The concentrations in these contaminated
media are such that, any releases to ambient air would be immediately diluted to
concentrations well below those of potential concern.
When will the cost coverage of the water treatment plant carbon filtration (GAC) unit
exchanges start?
EPA Response: EPA will evaluate the performance of the GAC system as the
Remedial Design is conducted after the ROD is signed. When the Remedial Action
begins (after RD is complete), EPA will fund any modifications to the GAC system
that are deemed necessary and then fund operation of the system for up to one year to
assure needed modifications are operational. After that, the system will transition to
Operation & Maintenance (O&M). EPA will then turn O&M responsibility over to
the state of Indiana.
What will be the relationship between EPA/contractors and the City Water Treatment
Plant personnel once EPA takes over GAC exchange responsibilities (GW2A)?
EPA Response: EPA, along with its contractor(s), will maintain communication
with IDEM and the City as it evaluates the performance of the GAC system during
RD and optimizes the system during RA. EPA will work collaboratively with all
parties to ensure the system is meeting the remedial action objectives of the ROD.
70
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Figures
-------
ILLINOIS
-J-
^Springfield Indianapolis
Martinsville, IN
OHIO
• Col urn bu'
INDIANA
Saint Louis
Cincinnati
3 ¦ { *
Frankfort Charleston'
Louisville
Ofiw
KENTUCKY
0.25
0.5
I
Figure 1
Site Location Map
Pike and Mulberry Streets PCE Plume Site
Martinsville, Indiana
*
MKE - R:\ENBG\00 Proj\E\EPA\Pike Mulberry\MapFiles\FS\Fig1-1 Site Location.mxd User Name: AESPEJO Date: 3/27/2018
cli2m-
-------
Artesian
(•) Master Wear
^ \_jfyiyy-2QS
¦ lfrlW-19S 79
iTneManitorium
Cleaners
Black
¦Lumber
Company
'Junkyard
Semi-truck
repair I
Central Dry
Cleaners
CMjSJ
Gunning ham
Highland
WtinBrfison
Morgan
Columbus
LEGEND
O Potential Past PCE User
& Former Master Wear Facility
Monitoring Well
Detected Above MCL
Detected Below MCL
Not Detected
Municipal Wells (PW)
# Detected Above MCL
® Detected Below MCL
@ Not Detected
Groundwater Contour Concentrations (pg/L)
100
46
5
Notes:
1. EPA = U.S. Environmental Protection Agency
2. G = indicates groundwater grab sample collected from soil
boring at approximately 10 ft. below ground surface
J = Estimated detection
MCL = Maximum Contaminant Level
PCE = tetrachloroethene
U = Result not detected
UJ = Estimated result not detected
8. pg/L = micrograms per liter
9. Dashed lines indicate where plume is inferred or estimated
10. PCE screening level (SL) = 5 pg/L
11. PCE in intermediate well MW-7M was 24 pg/L
Figure 2
PCE Exceedances in
Shallow Groundwater - Phase 3
Pike and Mulberry Streets PCE Plume Site
Martinsville, Indiana
MKE - R:\ENBG\00 Proj\E\EPA\Pike Mulberry\MapFiles\FS\Fig1-10 PCE GW Exceedances Ph3.mxd User Name: AESPEJO Date: 3/27/2018
cli2m-
-------
AA/HighlandSt
E Harrison St
W Harrison St
HAP-023
jPCE 30380
^S'G-OS
PCE 13000'
Martinsville: Cleaners
Artesian.City Cleaners
^ A
I I ^yTP®Ej2224 Z
SG-03
PCE 29000
W Morgan St
Kent Cleaners
O'Neal's.Clothes Depot
PCE^O0"80,?0
IT sg-01 A A/
/ PCE^'80O00A-^
Jz)AR=G)43
^CE 3608
Master Wear
E Washington St
' #
O' § SG-10
The, ManitoriuM Cleaners®
W Washington St
E Washington.St
HAP-007
fePCE 1044
Black- liumbe ^Company,
i
E Jackson St
W Jackson St
, 'Junkyard —'
Semhtruck repair
Central Dry Cleaners
E Columbus Si
W Columbus St
LEGEND
O Potential Past PCE User
^ Former Master Wear Facility
® Municipal Well
Residential (129.5)
Commercial/Industrial (90.5)
X No Sampling (park or parking lot) (18)
PCE Isocontours
Value
* 360
— 1400
5000
15000
25000
PCE Concentrations
Permanent Soil Vapor Probe with
results of PCE greater than the VISL
Permanent Soil Vapor Probe with
results of PCE below the VISL
Temporary Soil Vapor Point with HAPSITE
results of PCE greater than the VISL
Temporary Soil Vapor Point with
HAPSITE results of PCE below the VISL
A
Notes:
1. All units are in pg/m3
2. PCE VISL is 360 yg/m3
3. VISLs are based on EPA VISL Calculator Version 3.5.1
(EPA 2016) with May 2016 RSLs, a residential
exposure scenario, target Excess Lifetime Cancer Risk
(ELCR) of 1x10-6, and a Hazard Index of 1
4. The 1400 contour line represents the ELCR of 1x10-5
5. U = HAPSITE result is non-detect
6. E = HAPSITE result exceeds calibration range and result is
Estimated
7. PCE = tetrachloroethene
8. VISL = Vapor Intrusion Screening Level
All permanent soil vapor probe locations had soil vapor results
that exceeded the PCE VISLs in August and October 2015
except for SG-6, SG-13, and SG-17.
N
0 200 400
Feet
Figure 3
PCE Soil Vapor Results (Phases 2 through 5)
and Property Type Designations
Pike and Mulberry Streets PCE Plume Site
Martinsville, Indiana
cli2wL'
-------
W Highland St
E Harrison St
VV Harrison St
HAP-075
ITCE 65.6
Martinsville Gleaners
Artesiaff City Cleaners
Kent Cleaners Y J
O HAP-044
W Morgan St
SG-01 4
TC|..1600C'
Master Wear
iWI?5P41 ¦
TCE 32.2 U
E Washington St
W Washington St
The ManitoriumiCleaners
Black Lumber Company
¦it
E Jackson St
W Jackson St
leaners
Central
, 'Junkyard —'
Semi-truck repair
E Columbus St
W Columbus St
LEGEND
O Potential Past PCE User
Former Master Wear Facility
® Municipal Well
Residential (129.5)
Commercial/Industrial (90.5)
X No Sampling (park or parking lot) (18)
TCE Isocontours
16
1000
TCE Concentrations
Permanent Soil Vapor Probe with
^ results of TCE greater than the VISL
Permanent Soil Vapor Probe with
^ Detection Limit greater than the VISL
Permanent Soil Vapor Probe with
^ results of TCE below the VISL
Temporary Soil Vapor Point with HAPSITE
® results of TCE greater than the VISL
Temporary Soil Vapor Probe with
Detection Limit greater than the VISL
Temporary Soil Vapor Point with
• HAPSITE results of TCE below the VISL
Notes:
1. All units are in pg/m3
2. TCE VISL is 16 |jg/m3
3. VISLs are based on EPA VISL Calculator Version 3.5.1
(EPA 2016) with May 2016 RSLs, a residential
exposure scenario, target Excess Lifetime Cancer Risk
(ELCR) of 1x10-6, and a Hazard Index of 1
4. The 70 contour line represents the ELCR of 1x10-5
5. U = HAPSITE result is non-detect
6. E = HAPSITE result exceeds calibration range and result is
Estimated
7. TCE = trichloroethene
8. VISL = Vapor Intrusion Screening Level
All permanent soil vapor probe locations had soil vapor results
that exceeded the TCE VISLs in August and October 2015
except for SG-6, SG-13, and SG-17.
N
0 200 400
1 I I
Feet
Figure 4
TCE Soil Vapor Results (Phases 2 through 5)
and Property Type Designations
Pike and Mulberry Streets PCE Plume Site
Martinsville, Indiana
cli2wL'
-------
Figure 5 - Soil Sample Results from PCA for Master Wear Removal Action
AH ?/ .
m-22"
3.7oe< - s-1 a*:
AS =20
*#¦001(10-1 J')'
B
AMW-2M
&WH 7$
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u
t
Co
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a:
|
5
r<
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j^SiO-TrJftSV IBttfiKSSftV
M
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SVC-? ®
svs:-hii ©
s
u
D
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16(10*)
LEGgJVD
oSflY SML flQflWff
AtE 5GU. 8Q!M!G
AlE 5EGPRO&E
/III «LL
49? SFARKf Wf iU
a^v smscs ucMtcftw; WELL
SOU VAPOff £Xffi*Cfm *tu
SON. WW EXTRACTION UGWVPm WELL
DEM>TES SHALLOW *121
DEWTES m0t£ DEPTH WELL
DEHQ7ES DEEP WELL
TETZA&iLOPOETWlENE
PCE CGWEHTRAVQK (AT DEPTH)
SAkPiS OBTAINED AT M/MJU dGPsVl DEFJtf
Ail ANALYTICAL RESULTS *P£ REPORTED tot PP9
(PARTS PER BtLUOH)
ACI-J*
Hi Py Ap—*
33jQGG(15-fi7.5 i
"A5-4A
390(15. 17,5")
PAflKMr
SP-W?«
SVE-U2
x-i e .
i«,i:o:i(!o
SB-M - * D,W3('9')
SS-M /„ 5B-W
, ICO( 16-20')--^ 160(18"!
*7,000(17.5-20') * at-1®
AB-56 +
"« IB
A3-1!
110^7.5 *201
ss—*a j
s-wCB'rjJasp-in
SH-4 AD-17
*5-17 S
50,M)()r'5-17.5l .
3«p5-17.5^
Ht,«f fiwr
50C18-2C')
HP
*
iiL,ak
-------
Kent Cleaners
£r\ —
Artesian City/Cjeaners
[Centra I! Dry.Clea ners
I M a st e r We a r. S i tej
fcThe Man ito riu m [CIea ners
BlackLumber Company
Junky a rb]
Bedrock
Groundwater Level —
Cll2tW
Groundwater Contour Concentrations (|ig/L)
5
50
100
Soil Vapor Contour Concentrations (ng/L)
360
Figure 6
Conceptual Site Model - PCE in
Groundwater and Soil Vapor
Pike and Mulberry Streets PCE Plume Site
Martinsville, Indiana
LEGEND
O Potential Past PCE User
^ Master Wear Site
© Monitoring Well
Soil Gas Sample
0 Municipal Well
© Residential Well
Fill, Lean Clays, and Silts
Sand and Gravel Aquifer
I Silt, Sandy Loam, and Sandy Clay
EN 1003161124MKE Figure_7-l_CSM_V2.ai 06.05.2017 tdaus
-------
Kent Cleaners
£r\ —
Bwviw^S
Artesian City Cleaners
fee ntra I! Dry.Clea ners
MasterWearSite
|The Man ito riu m [CIea ners
Black*Lumber Company^
Junky a rb]
Soil Vapor Contour Concentrations (|Ag/L)
16
—— 1000
LEGEND
O Potential Past PCE User
(•) Master Wear Site
© Monitoring Well
Soil Gas Sample
0 Municipal Well
© Residential Well
Fill, Lean Clays, and Silts
Sand and Gravel Aquifer
J Silt, Sandy Loam, and Sandy Clay
| Bedrock
X Groundwater Level
Ck2ffll:
tf t
600
590 -1
580
570 -
=• 560
1 550 -
r 540
I 530 -
520
510 -
500
490 -
480
Figure 7
Conceptual Site Model - TCE in
Groundwater and Soil Vapor
Pike and Mulberry Streets PCE Plume Site
Martinsville, Indiana
¦¦¦UMH "* i t- X-is-~ tiSK
-------
WighlandSt.
Hams on St
Kent Cleaners
Artesian City Cleaners"
, Morgan St.
MW-2® '
• i - ^SG-04:,, <
VThe Manitorium'cleanersl
S G 10*4
mw;i1
- MasterWear Site
Utility Corridor
Washington St.
PCE Groundwater Contour Concentrations (ng/L)
5
50
100
PCE Soil Vapor Contour Concentrations (|ig/L)
¦ 360
1,400
5,000
15,000
¦ 25,000
TCE Groundwater Contour Concentrations ((ig/L)
16
70
1000
Screening Levels
PCE-8,100 pg/kg
TCE - 410 |Jg/kg
I
LEGEND
o
Potential Past PCE User
Master Wear Site
©
Monitoring Well
A
Soil Gas Sample
•
Municipal Well
•
Residential Well
Fill, Lean Clays, and Silts
Sand and Gravel Aquifer
Silt, Sandy Loam, and Sandy Clay
Bedrock
3r
Groundwater Level
Figure 8
Conceptual Site Model - PCE and TCE in Soil
Pike and Mulberry Streets PCE Plume Site
Martinsville, Indiana
-J
Cil2tn
EN 1003161124MKE Figure_7-3_CSM_V5.ai 06.05.2017 tdaus
-------
Water
Treatment Plant
W Highland St
E!Harrison St
W Harrison St
Kent Cleaners
Artesian City., Cleaners
iaster Wear
W Washington St
E .Washington,St
The Manitorium Cleaners
Black Lumber Company
WiJackson'St
E'Jackson St
Central Dry Cleaners!
Junkyard
Semi-truck repair
E Columbus St
W Columbus'St
4
LEGEND
O Potential Past PCE User
& Former Master Wear Facility
© Monitoring Well
® Municipal Well
Q Permanent Soil Vapor Probe Location
Residential
Commercial/Industrial
~ Municipal Wellfieid
~ Water Treatment Plant
Note:
Location of Nutter Ditch is approximate.
Figure 9
Site Features and Land Use
Pike and Mulberry Streets PCE Plume Site
Martinsville, Indiana
cli2m-
-------
Appendix A
Administrative Record Index
-------
U.S. ENVIRONMENTAL PROTECTION AGENCY
REMEDIAL ACTION
ADMINISTRATIVE RECORD ~
FOR THE
PIKE AND MULBERRY STREETS PCE PLUME SITE
MARTINSVILLE, MORGAN COUNTY, INDIANA
UPDATE 1
FEBRUARY 25, 2021
SEMS ID: 956347
NO.
1
SEMS ID DATE
237819
8/12/05
AUTHOR RECIPIENT TITLE/DESCRIPTION PAGES
U.S. EPA U.S. EPA Administrative Record Site 2
File Index Masterwear Update
#1 Removal Action (This
Document is Included for
Informational Purposes
Only)
313351 11/20/08 U.S. EPA U.S. EPA Administrative Record Site
File Index Masterwear Update
#2 Removal Action (This
Document is Included for
Informational Purposes
Only)
353222 12/22/08 Astbuiy U.S. EPA
Environmental
Engineering
Former Masterwear Closure
Report (This Document is
Included for Informational
Purposes Only)
68
956308
7/1/10 IDEM
U.S. EPA Map: Re: Masterwear Site
Re-assessment July-August
2010 Groundwater and Soil
956325 12/11/11 City of U.S. EPA
Martinsville
Water Utility
Table Re: Water Utility
Service Cost
-------
956342 12/16/13 Hardin, E., U.S. EPA Confidential Enforcement - 29
U.S. EPA File Draft of Potentially
Responsible Parties (This
Document is Included for
Informational Purposes
Only)
956323 6/1/15 CH2M U.S. EPA Map Re: Soil Gas Impacted
Area - Soil Vapor Probe
VOC
956346 2/11/16 Olsson, D., Hardin, E., Report on Work Plan
CH2M U.S. EPA Revision Request #1 -
Remedial
Investigation/Feasibility
Study (This Document is
Included for Informational
Purposes Only)
42
9 956338 5/31/16
Knoepfle, J., Hardin, E.,
CH2M U.S. EPA
Email Re: VI Sample 40
Results that exceed RML's -
Analysis (This Document is
Included for Informational
Purposes Only)
10 956317 6/1/16 CH2M U.S. EPA Final Quality Assurance
Project Plan Addendum 3
on Pike & Mulberry Street
PCE Plume Site
74
11 956312 9/13/16 Jones, K., Manley, S., Potentiometric Surface-
Pace Analytical City of Shallow Water Bearing
Martinsville
12
940584 9/13/16 Walterman, D., Hardin, E.,
IDEM U.S. EPA
Letter: Re: Applicable or
Relevant and Appropriate
Requirements (ARARs) for
Pike & Mulberry Street PCE
Plume Site
13 956322 12/22/16 Gahala, A., Hardin, E.,
U.S. Geological U.S. EPA
Survey
Hydrologist Memo Re:
Potential for Co-Mingling
Plume with O'Neal
Investigation
14 956320 1/1/17 CH2M Hardin, E., Remedial Alternatives
U.S. EPA Screening Report
210
15 956319 2/10/17 Walter, D., Hardin, E.,
IDEM U.S. EPA
Letter Re: Remedial
Alternatives Screening
3
-------
Email Re: VI Sample 3
Results that Exceeds RML's ¦
Analysis (This Document is
Included for Informational
Purposes Only)
Email Re: VI Sample 4
Results that Exceeds RML's ¦
Analysis (This Document is
Included for Informational
Purposes Only)
[Redacted] Final Remedial 1664
Investigation Report of
Pike & Mulberry Street PCE
Plume Site
16 956324 3/15/17
17 956344 3/23/17
18 956314 4/1/18
19 237819 7/16/18
20 956309 10/18/18
21 956310 10/30/18
22 949417 8/1/19
23 951485 12/11/19
Knoepfle, J., Hardin, E.,
CH2M U.S. EPA
Knoepfle, J., Hardin, E.,
CH2M U.S. EPA
CH2M U.S. EPA
U.S. EPA U.S. EPA
File
Jones, K., Manley, S.,
Pace Analytical City of
Martinsville
Jones, K., Manley, S.,
National City of
Environmental Martinsville
Testing Inc.
Safakas, K., Hardin, E.,
U.S. EPA U.S. EPA
CH2M U.S. EPA
Administrative Record Site 1
Index Pike and Mulberry
Streets PCE Plume Site -
Original Removal Action
19
Analytical Sample Results 15
Applicable to TNI/NELAC
Standards
Pike & Mulberry Streets 46
PCE Plume Site Community
Involvement Plan
[Redacted] Final Feasibility 377
Study
Certifications, Sample
Summary, Summary of
Detection, Analytical
Results and Chain of
Custody Reoort
24 956321 4/16/20 U.S. Dept. of Hardin, E.,
Human Health U.S. EPA
Report Re: Analysis of 59
Contaminants in Drinking
Water and Indoor Air
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25 956318 5/12/20 Hardin, E., U.S. EPA Memo Re: Technical
U.S. EPA File Memorandum of
Supplemental Evaluation of
In Situ Sorbent Reactive
Media (SRM) for
Groundwater Remediation
26 956339 7/1/20
City of Hardin, E.,
Martinsville U. S. EPA
Water and
Utility
Planning and Engineering 1
Work Estimate Per
Residence for Replacing
City Water Line (This
Document is Included for
Informational Purposes
Only)
27 956316 8/1/20 Hardin, E., U.S. EPA Superfund Proposed Plan of
U.S. EPA File Pike & Mulberry Street PCE
Plume Site
51
28 956313 8/4/20 Hardin, E., U.S. EPA Map Re: Pike & Mulberry
U.S. EPA File Street PCE Plume Site
Exceedances in Shallow
Groundwater
29 956345 8/5/20 Hardin, E., U.S. EPA
U.S. EPA File
Private Residential Well
Summary (This Document
is Included for
Informational Purposes
Only)
30 956340 8/5/20 Hardin, E., U.S. EPA
U.S. EPA File
Confidential Map of Phase 2
Private Residential
Groundwater Sampling
(This Document is Included
for Informational Purposes
Only)
31 956341 8/5/20
Hardin, E., U.S. EPA
U.S. EPA File
Confidential Map Re: First 1
Round of Removal VI
Results (This Document is
Included for Informational
Purposes Only)
32 956336 8/12/20 Hardin, E., U.S. EPA [Redacted] Transcript of 35
U.S. EPA File Virtual Public Comment
Meeting on Pike &
Mulberry Street PCE Plume
Site
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33 956335 8/18/20 Smith, B., Safakis, K.,
Proxychem U.S. EPA
Letter Re: Proxychem
Comment on Pike &
Mulberry Street PCE Plume
Site
34 956337 8/31/20 Safakas, K., Hardin. E.. [Redacted] Re: Public
U.S. EPA U.S. EPA Comments on Pike &
Mulberry Street PCE Plume
Site
40
35 956331 8/31/20 Safakas, K., Hardin, E., [Redacted] Re: Public
U.S. EPA U.S. EPA Comment of Concerned
Citizen on Pike & Mulberry
Street PCE Plume Site
36 956326 9/3/20 Safakas, K., U.S. EPA [Redacted] Written
U.S. EPA File Comment Form - From
Concerned Citizen on Pike
& Mulberry Street PCE
Plume Site
37 956333 9/9/20 Safakas, K., U.S. EPA [Redacted} Concerned
U.S. EPA File Citizen Comment on Pike &
Mulberry Street PCE Plume
Site Via Email
38
956332
9/14/20
Mayor Costin, U.S. EPA
K.,
City of
Martinsville
File
Letter Re: Mayor's
Comments With Fifteen
Questions on Pike &
Mulberry Street PCE Plume
Site
13
39 956334 9/22/20 Safakas, K., U.S. EPA [Redacted] Concerned
U.S. EPA File Citizen Comment From
Concerned Citizen - With
Eleven Questions on Pike &
Mulberry Street PCE Plume
Site
40 956327 10/2/20 Safakas, K., U.S. EPA [Redacted] Public Notice
U.S. EPA File Form - Comment and Four
Questions From Concerned
Citizen on Pike & Mulberry
Street PCE Plume Site Via
Email
41 956328 10/2/20 Safakas, K., U.S. EPA [Redacted] Form Comment
U.S. EPA File From Concerned Citizen on
Pike & Mulberry Street PCE
Plume Site Via Email
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956329 10/2/20 Safakas, K.,
U.S. EPA
U.S. EPA [Redacted] Form Comment
File From Concerned Citizen on
Pike & Mulberry Street PCE
Plume Site Via Email
956330 10/2/20 Safakas, K.,
U.S. EPA
U.S. EPA [Redacted] Form Comment
File From Concerned Citizen on
Pike & Mulberry Street PCE
Plume Site Via Email
956315 2/11/21 Dorsey, P.,
IDEM
U.S. EPA
File
Letter Re: Concurrence of
Record of Decision
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Appendix B
IDEM Concurrence Letter on ROD
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idem Indiana Department of Environmental Management
We Protect Hoosiers and Oar Environment.
100 N. Senate Avenue • Indianapolis, IN 46204
(800)451-6027 • (317)232-8603 • www.idem.IN.gov
Eric J. Holcomb Bruno L. Pigott
Governor Commissioner
February 11, 2021
Doug Ballotti, Superfund Division Director
U.S. EPA, Region 5
77 West Jackson Boulevard, Mail Code SR-6J
Chicago, IL 60604
Dear Mr. Ballotti:
Re: Record of Decision for the Pike and Mulberry
Groundwater Plume Superfund Site,
Martinsville, IN
The Indiana Department of Environmental Management (IDEM) has reviewed the U.S.
Environmental Protection Agency's Record of Decision (ROD) document for the Pike and
Mulberry Groundwater Plume Superfund site located in Martinsville, Indiana. IDEM is in full
concurrence with the selected remedy outlined in the document, which includes:
• Groundwater Alternative GW-2A (Granular Activated Carbon) at the City's WTP;
• Groundwater Alternative GW-5 (In Situ Chemical Reduction) with a contingency to
implement Groundwater Alternative GW-6 (In Situ Chemical Oxidation); and
• Soil Vapor Alternative SV-5 (Pathway Sealing, Vapor Intrusion Mitigation, and Soil Vapor
Source Removal).
IDEM staff have been working closely with Region 5 staff in the selection of the
appropriate remedy and are satisfied with the chosen alternative. Please be assured that IDEM
is committed to accomplish cleanup at all Indiana sites on the NPL and intends to fulfill all
obligations required by law to achieve that goal. We look forward to beginning work on this next
phase of the project.
Sincerely,
I
Peggy Dtifse
Assistant Commissioner
Office of Land Quality
PD:JHF:jhf
cc:Rex Osborn, IDEM
Erik Hardin, EPA
0
Ail Equal Opportunity Employer A State that Works 0 Recycled Paper
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