Record of Decision Southwest Properties Wells G&H Superfund Site Operable Unit 4 September 2017


U.S. ENVIRONMENTAL PROTECTION AGENCY

REGION 1

RECORD OF DECISION
SOUTHWEST PROPERTIES
WELLS G&H SUPERFUND SITE
OPERABLE UNIT 4

SEPTEMBER 2017

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Record of Decision
Table of Contents

PART 1: THE DECLARATION

A.	SITE NAME AND LOCATION

B.	STATEMENT OF BASIS AND PURPOSE

C.	ASSESSMENT OF SITE

D.	DESCRIPTION OF SELECTED REMEDY

E.	STATUTORY DETERMINATIONS

F.	SPECIAL FINDINGS

G.	DATA CERTIFICATION CHECKLIST

H.	AUTHORIZING SIGNATURES

PART 2: THE DECISION SUMMARY

A.	SITE NAME, LOCATION AND BRIEF DESCRIPTION

B.	SITE HISTORY AND ENFORCEMENT ACTIVITIES

1.	History of Site Activities

2.	History of Federal and State Investigations and Removal and Remedial Actions

3.	History of CERCLA Enforcement Activities

C.	COMMUNITY PARTICIPATION

D.	SCOPE AND ROLE OF OPERABLE UNIT OR RESPONSE ACTION

E.	SITE CHARACTERISTICS

F.	CURRENT AND POTENTIAL FUTURE SITE AND RESOURCE USES

1.	Land Uses

2.	Groundwater Uses

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Southwest Properties, Operable Unit 4 (OU4)

Wells G&H Superfund Site
Woburn, Massachusetts

September 2017
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G.	SUMMARY OF SITE RISKS

1.	Human Health Risks

2.	Ecological Risks

3.	Basis for Response Action

H.	REMEDIATION OBJECTIVES

I.	DEVELOPMENT AND SCREENING OF ALTERNATIVES
J. DESCRIPTION OF ALTERNATIVES

1.	Source Control (SC) Alternatives Analyzed

2.	Management of Migration (MM) Alternatives Analyzed

K.	SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES

L.	THE SELECTED REMEDY

M.	STATUTORY DETERMINATIONS

N.	DOCUMENTATION OF SIGNIFICANT CHANGES

O.	STATE ROLE

PART 3: THE RESPONSIVENESS SUMMARY

A.	PUBLIC COMMENTS AND EPA RESPONSES

APPENDICES

Appendix A: State DEP Letter of Concurrence

Record of Decision

Southwest Properties, Operable Unit 4 (OU4)
Wells G&H Superfund Site
Woburn, Massachusetts

September 2017
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Appendix B: Tables
Appendix C: Figures
Appendix D: ARARs Tables
Appendix E: TSCA Determination
Appendix F: Acronyms and Abbreviations

Appendix G: Administrative Record Index and Guidance Documents

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Part 1: The Declaration

PART I - DECLARATION FOR THE RECORD OF DECISION

A.	SITE NAME AND LOCATION

Wells G&H Superfund Site
Woburn, Massachusetts
CERCLIS ID # MAD980732168
Southwest Properties, Operable Unit 4 (OU4)

B.	STATEMENT OF BASIS AND PURPOSE

This decision document presents the selected remedial action for the Southwest Properties
(SWP), Operable Unit 4 (OU4) of the Wells G&H Superfund Site (Site), in Woburn,
Massachusetts, which was chosen in accordance with the Comprehensive Environmental
Response, Compensation and Liability Act of 1980, as amended (CERCLA), 42 USC §§ 9601 et
seq., and, to the extent practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan, as amended (NCP), 40 C.F.R. Part 300 et seq. The Director of the Office of
Site Remediation and Restoration (OSRR) has been delegated the authority to approve this
Record of Decision (ROD).

During previous Remedial Investigation / Feasibility Study (RI/FS) activities, the SWP were
considered a portion of the Central Area, which is Operable Unit 2 (OU2) of the Wells G&H
Superfund Site. Under this ROD, the SWP cleanup has been separated from OU2 and is now
designated as OU4.

This decision document was based on the Administrative Record, which has been developed in
accordance with Section 113(k) of CERCLA, and which is available for review at the Woburn
Public Library and at the United States Environmental Protection Agency (EPA) Region 1
OSRR Records Center in Boston, Massachusetts. The Administrative Record Index (Appendix
G to the ROD) identifies each of the items comprising the Administrative Record upon which the
selection of the remedial action is based.

The Commonwealth of Massachusetts (the Commonwealth) concurs with the Selected Remedy
(See Appendix A).

C.	ASSESSMENT OF THE 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. The November 2016 Remedial Investigation (RI) Report for the SWP summarizes
the nature and extent of the contamination and was used to prepared a December 2016
Feasibility Study (FS) Report that identified all the remedial options considered for cleanup of
the SWP. In addition, EPA prepared a July 2017 FS Report Addendum - Technical
Memorandum which modifies sections of the FS and supports this ROD.

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D.	DESCRIPTION OF THE SELECTED REMEDY

This ROD sets forth the selected remedy for the SWP (OU4 of the Wells G&H Superfund Site),
which involves the excavation and off-site disposal of principal threat source material within the
Northern Whitney Soil Area and Non-Aqueous Phase Liquid (NAPL) Areas and the excavation
and off-site disposal of low-level threat contaminated wetland sediment/soil from the Murphy
Wetland which exceed human health and/or ecological risk standards; restoration of the Murphy
Wetland; the excavation and off-site disposal of soil to facilitate capping and maintain flood
storage; and the capping of soil across the Murphy, Whitney and Abeijona Properties which
exceed human health cleanup levels for direct contact and/or leaching of contaminants to
groundwater. The selected remedy also includes extraction and treatment of contaminated
groundwater containing volatile organic compounds (VOCs), semi-volatile organic compounds
(SVOCs), petroleum hydrocarbon fractions, pesticides, polychlorinated biphenyls (PCBs) and
metals in overburden and bedrock aquifers and long-term monitoring to monitor the
effectiveness of the treatment. To facilitate future use and redevelopment of the SWP consistent
with the cleanup, the selected remedy also includes Institutional Controls which will preserve the
remedy and ensure that impacted soil and groundwater encountered during future intrusive
activities (e.g., installing subsurface utilities, building foundations/slabs, etc.) is appropriately
managed to protect human health and the environment. Periodic Five Year Reviews are required
to assess protectiveness.

The selected remedy is a comprehensive approach for the SWP that addresses all current and
potential future risks caused by soil, groundwater, and wetland sediment/soil contamination, and
results in no net flood storage loss. The remedial measures will remove principal threat source
material from the SWP, remove low-level threat contaminated wetland sediment/soil from the
Murphy Wetland and restore the wetland area, cap the low-level threat soils across the SWP to
prevent exposure and the future leaching from the low-level threat soils into the groundwater in
excess of drinking water standards; restore groundwater within the contaminant plume to a level
protective of human health and the environment; and will allow for restoration of the SWP to
beneficial uses. Institutional Controls will be used as part of the selected remedy to maintain the
soil caps, prevent residential, school, and daycare uses of the properties, prevent exposure to
contaminated groundwater until the cleanup standards are met and to require evaluation of the
vapor intrusion pathway.

The major components of the selected remedy are:

1. Excavation and off-site disposal of approximately 5,400 cubic yards of significantly
contaminated soil1 at the designated Northern Whitney Soil Area, and blending remaining
contaminated soil below the water table with an amendment (e.g., Zero-Valent Iron
(ZVI)) prior to backfilling to provide soil and localized groundwater treatment. In
addition, excavation and off-site disposal of approximately 12,400 cubic yards of soil in
the Murphy upland, Whitney, and Abeijona Property areas to facilitate installation of

1 "Significantly contaminated soil" defined as soil with contaminant concentrations 10 times greater than the soil
cleanup levels and/or greater than or equal to 50 milligrams per kilogram (mg/kg - equivalent to ppm) of PCBs.

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impermeable caps (for a total of approximately 18,000 cubic yards of excavated soil).
Construction of impermeable caps over areas with lower concentration soils that exceed
cleanup levels to reduce soil exposure risks and/or prevent contaminant movement to
groundwater;

2.	Excavation and off-site disposal of NAPL in the Murphy and Whitney Property areas,
including approximately 6,000 cubic yards of NAPL-contaminated soil and the blending
any remaining NAPL-contaminated soil below the water table with an amendment (e.g.,
ZVI) prior to backfilling to provide soil and localized groundwater treatment;

3.	Containment and cleanup of groundwater contaminants throughout OU4 by pumping and
treating the groundwater;

4.	Excavation and off-site disposal of approximately 7,000 cubic yards of wetland
sediment/soil from the Murphy Wetland exceeding cleanup levels and wetland
restoration;

5.	Long-term monitoring and periodic Five-Year Reviews;

6.	Institutional Controls to maintain the integrity of the soil caps and other remedial
components; to prevent development of the properties for residential, school, and daycare
use (except on the Aberjona residential area); to prohibit use of contaminated
groundwater until cleanup levels are met; and to require evaluation of the vapor intrusion
pathway if a change in usage of any of the existing buildings is contemplated or as part of
new building construction, including any addition/alteration to existing buildings on any
of the properties.

A RI/FS of the OU2 Central Area was undertaken by several of the OU1 Settling Defendants
(e.g. Beatrice Company (Beatrice), UniFirst Corporation and W.R. Grace & Co.) and submitted
to EPA in February, 1994. A separate RI was also undertaken by Beatrice which specifically
addressed the SWP (February, 1994). This separate RI for the SWP was supplemented with an
August 2003 RI report by Beatrice. Following this work, EPA issued a Baseline Human Health
Risk Assessment (BRA) for the SWP in March 2004, which was later updated in February 2006.
This work necessitated a third phase of RI activities at the SWP in 2010 to 2013, including
additional groundwater and soil samples. A final BRA for the SWP was issued by EPA in 2014
(EPA, 2014). A RI Report (November 2016) and FS Report (December 2016) were submitted by
Beatrice Company. EPA then prepared an FS Report Addendum - Technical Memorandum for
the SWP (July 2017) which modified sections of the FS. Under this ROD, the SWP cleanup has
been designated as Operable Unit 4 (OU4).

The selected remedy addresses principal and low-level threat wastes at the SWP by: 1) the
excavation and off-site disposal of principal threat waste source soils and NAPL; 2) the
excavation and off-site disposal low-level threat wetland sediments/soils; 3) the capping of
remaining low-level threat soils to eliminate exposure to these soils; and 4) the treatment of
contaminated groundwater to restore groundwater to levels protective of human health and the
environment.

E. STATUTORY DETERMINATIONS

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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
(unless justified by a waiver), is cost-effective, and utilizes permanent solutions and alternative
treatment (or resource recovery) technologies to the maximum extent practicable.

Based on technology and space considerations, EPA concluded that it was impracticable to
excavate and treat the chemicals of concern in soils, sediments, and NAPL in a cost-effective
manner. However, backfilling NAPL and deeper soil excavations with amendment will provide
localized soil and groundwater treatment, and dewatering activities associated with
implementing the soils, sediments and NAPL work will provide treatment of water prior to
discharge. In addition, the selected remedy for groundwater will satisfy the statutory preference
for treatment. Thus, the overall selected remedy partially satisfies the statutory preference for
treatment as a principal element of the remedy.

Because this remedy will result in hazardous substances remaining on-site above levels that
allow for unlimited use and unrestricted exposure (and groundwater and land use restrictions are
necessary), a review will be conducted within five years after initiation of remedial action to
ensure that the remedy continues to provide adequate protection of human health and the
environment.

F. SPECIAL FINDINGS

Issuance of this ROD embodies the following specific determinations:

Wetland Impacts

Pursuant to Section 404 of the Clean Water Act (CWA), 44 C.F.R. Part 9, and Executive Order
11990 (Protection of Wetlands), EPA has determined that there is no practicable alternative to
conducting work that will impact wetlands of the United States because significant levels of
contamination exist within wetlands of the United States and these areas are included within the
SWP's cleanup areas.

For those areas impacted by cleanup activities, EPA has also determined that the cleanup
alternatives that have been selected are the Least Environmentally Damaging Practicable
Alternatives (LEDPA), as required by the CWA, because they will permanently remove
contaminants that are impairing the wetlands and any wetland resources altered by the cleanup
will be restored to the original grade and with native vegetation.

EPA will minimize potential harm and avoid adverse impacts on resources, to the extent
practical, by using best management practices to minimize harmful impacts on the wetlands,
wildlife or habitat. Wetlands will be restored and/or replicated consistent with the requirements
of federal and state wetlands protection laws.

Floodplain Impacts

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The cleanup plan selected by EPA includes activities that result in the occupancy and
modification of the 500-year floodplain. Pursuant to Federal Emergency Management Agency
(FEMA) regulations at 44 C.F.R. Part 9, which set forth the policy, procedure and
responsibilities to implement and enforce Executive Order 11988 (Floodplain Management),
EPA has determined that there is no practicable alternative to altering floodplain resources.

EPA will avoid or minimize potential harmful temporary or permanent impacts on floodplain
resources within the 500-year floodplain to the extent practicable at the cleanup areas including
the Murphy Wetland. In addition, any lost flood storage capacity from cleanup activities within
the 500-year floodplain will be addressed as appropriate. The remedy includes provisions for no
net flood storage loss (e.g., soil removal prior to cap installation so no net flood storage loss,
sediments removed and clean wetland soils backfilled to original grades, etc.).

Toxic Substances Control Act

In accordance with the requirements under the Toxic Substances Control Act (TSCA) and 40
C.F.R. § 761.61(c), EPA has made a finding that the manner of sampling, storage, cleanup and
disposal of PCB-contaminated soil, wetland sediment/soil, groundwater and NAPL as set out in
this Record of Decision will not pose an unreasonable risk of injury to health or the environment
as long as the following conditions are met:

•	The selected contractor for the PCB remediation work shall submit a contractor work plan
describing the containment and air monitoring that will be employed during PCB remedial
activities, including but not limited to site control, excavation, handling, storage, and disposal
activities. This work plan should also include information on how and where all PCB
remediation waste will be accumulated/stored prior to off-site shipment/disposal and how the
PCB remediation waste will be disposed of; how storm water controls and runoff will be
managed; how dust levels will be controlled and monitored; and how field equipment will be
decontaminated.

•	Soil in the "Northern Whitney Soil Area" contains concentrations of PCB higher than other
areas (by 10 to 100 times) attributable to the former drum storage and washing operations
area and the former floor drain line on both the Whitney and Aberjona Properties.

Excavation of soils in the Northern Whitney Soil Area will include all soils with total PCBs >
50 parts per million (ppm) and soils with residual Non-Aqueous Phase Liquid (NAPL).
Excavation is assumed to include excavation of soils below the water table. Water removed
from the excavations will be tested and treated if necessary to meet the TSCA discharge
standard of 0.5 ppb PCBs to be discharged to a nearby surface water body (e.g., Abeijona
River) or appropriated off-site disposal at a permitted facility, or appropriate POTW. In
areas where soil with total PCBs > 50 ppm extend into the water table, the saturated soils will
be excavated to approximately 15 feet in depth. Excavated soils will be moved to a stockpile
area for dewatering and stabilization to facilitate transport to the disposal facility. Any free
water generated from the dewatering process will be tested and treated if necessary to meet
the TSCA discharge standard of 0.5 ppb PCBs to be discharged to a nearby surface water

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body (e.g., Abeijona River) or appropriate off-site disposal at a permitted facility, or
appropriate approved POTW. Additional amendments, if required, may be added to
dewatered soil, as necessary for off-site disposal. Prior to off-site disposal, the soil stockpiles
will be covered to prevent storm water impacts. Direct loading of excavated soils into trucks
for off-site disposal is also possible if the soil has been pre-characterized and is sufficiently
dry. An amendment will be mixed into soil below the water table to reduce/destroy VOC
contamination in soil and will also result in reduction of PCB mobility. The area will then be
backfilled and compacted to pre-excavation elevations using clean fill. All PCB-
contaminated soils with > 50 ppm will be disposed off-site at a TSCA-approved disposal
facility or a Resource Conservation and Recovery Act (RCRA) hazardous waste landfill in
accordance with 40 C.F.R. § 761,61 (a)(5)(i)(B)(2)(///), Confirmatory sampling will be
conducted in accordance with 40 C.F.R. Part 761, Subpart O to document that all PCBs with
> 50 ppm have been removed and to support that PCB concentrations are < 50 ppm for off-
site disposal if additional soil removal is required.

• NAPL-related PCB impacts at two other locations on the Murphy Property contain

significantly impacted soils (e.g., total PCBs > 50 ppm) from former waste oil management
operations. The excavations will proceed approximately 5 to 6 feet into the water table to a
total depth of approximately 12 feet below grade. Sidewall excavation delineation from pre-
design and post-excavation bottom samples will be collected and tested to confirm that the
NAPL is completely removed, to the extent practicable. Water removed from the
excavations will be tested and treated if necessary to meet the TSCA discharge standard of
0.5 ppb PCBs to be discharged to a nearby surface water body (e.g., Abeijona River) or
appropriate off-site disposal at permitted facility, or appropriate approved POTW. A survey
will be conducted to document the final excavation depth and in each area sampling will be
conducted per 40 C.F.R. Part 761, Subpart O to document that all soils with PCBs > 50 ppm
have been removed. Excavated soils will be moved to a stockpile area for dewatering and
stabilization, if necessary, to facilitate transport to the disposal facility. Any free water
generated from the dewatering process will be tested and treated if necessary to meet TSCA
discharge standard of 0.5 ppb PCBs to be discharged to a nearby surface water body (e.g.,
Aberjona River) or appropriate off-site disposal at a permitted facility, or appropriate
approved POTW. Additional amendments, if required, may be added to dewatered
soil/NAPL, as necessary for off-site disposal. Prior to off-site disposal, the soil stockpiles
will be covered to prevent storm water impacts. Direct loading of excavated soils into trucks
for off-site disposal is also possible if the soil has been pre-characterized (via in situ
sampling) and is sufficiently dry. The area will be backfilled and compacted to pre-
excavation elevations using clean fill and an amendment mixed in to soil below the water
table. These NAPL-related PCB-contaminated soils at the Murphy property with > 50 ppm
shall be excavated and disposed off-site at a TSCA-approved disposal facility or a RCRA
hazardous waste landfill in accordance with 40 C.F.R. § 761.61(a)(5)(i)(B)f2)(/w).

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• Remaining PCB remediation waste in upland soils at the SWP that exceed risk-based cleanup
levels will be under a protective cap consisting of a uniform placement of concrete,
engineered asphalt/bituminous concrete, engineered impermeable cap, or similar material of
minimum thickness spread over the area where PCB remediation waste has been left in place
in order to: a) prevent/minimize human exposure and reduce ecological impacts, b)
prevent/minimize infiltration of water, and c) prevent/minimize erosion per 40 C.F.R. §
761.61(a)(7). Institutional Controls will be used to protect the integrity of the protective
caps. PCB-contaminated soils that need to be excavated as part of the cap construction to
provide no net flood storage loss will be moved to a stockpile area, dewatered, and stabilized
to facilitate transport to a disposal facility. Water removed from the excavations or from soil
dewatering will be tested and treated if necessary to meet the TSCA discharge standard of 0.5
ppb PCBs to be discharged to a nearby surface water body (e.g., Abeijona River) or
appropriate off-site disposal at a permitted facility, or appropriate approved POTW.
Additional amendments, if required, may be added to dewatered soil/NAPL, as necessary for
off-site disposal. Prior to off-site disposal, the soil stockpiles will be covered to prevent
storm water impacts. Direct loading of excavated soils into trucks for off-site disposal is also
possible if the soil has been pre-characterized and is sufficiently dry. PCB-contaminated soils
shall be disposed off-site at a TSCA-approved disposal facility or a RCRA hazardous waste
landfill in accordance with 40 C.F.R. § 761,61 (a)(5)(i)(B)(2)(//7), Alternatively, PCB-
contaminated soils may be disposed at a state-permitted landfill in accordance with 40 C.F.R.
§ 761,61 (a)(5)(i)(B)(2)(/7) provided in situ (prior to excavation) sampling confirms PCB
concentrations are < 50 ppm. Confirmatory sampling will not be required where remaining
PCB-contaminated soil will be under the protective cap.

• All PCB-contaminated upland soils exceeding 1 ppm total PCBs shall be subject to
institutional controls restricting residential, school, and daycare uses.

• For the wetland area, the lower of the applicable human health and ecological cleanup levels
will be applied for the remedial actions (i.e., 1.9 ppm total PCBs for wetland sediment and
1.3 ppm total PCBs for wetland soil). All wetland sediment/soil with PCB concentrations at
or above these cleanup levels will be excavated and disposed off-site at a TSCA-approved
disposal facility or a RCRA hazardous waste landfill in accordance with 40 C.F.R. §
761.61(a)(5)(i)(B)(2)(/«). Water removed from the excavations or from sediment/soil
dewatering will be tested and treated if necessary to meet the discharge standard of 0.5 ppb
PCBs to be discharged to a nearby surface water body (e.g., Aberjona River) or appropriate
off-site disposal at a permitted facility, or appropriate approved POTW. Additional
amendments, if required, may be added to dewatered soil/NAPL, as necessary for off-site
disposal. Prior to off-site disposal, the sediment/soil stockpiles will be covered to prevent
storm water impacts. Direct loading of excavated soils/sediments into trucks for off-site
disposal is also possible if the soil/sediment has been pre-characterized and is sufficiently
dry. Confirmatory sampling will be performed to demonstrate that all wetland sediment/soil

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with PCB concentrations exceeding the cleanup levels have been excavated. PCB-
contaminated wetland sediment/soil shall be disposed off-site at a TSCA-approved disposal
facility or a RCRA hazardous waste landfill in accordance with 40 C.F.R. §
761,61 (a)(5)(i)(B)(2)(777). Alternatively, PCB-contaminated sediment/soil may be disposed
at a state-permitted landfill in accordance with 40 C.F.R. § 761,61 (a)(5)(i)(B)(2)(//) provided
in situ (prior to excavation) sampling confirms PCB concentrations are < 50 ppm.

• Groundwater removed from the pump and treatment system will be treated, as required, to
meet the TSCA PCB discharge standard of 0.5 ppb PCBs to be discharged to a nearby
surface water body (e.g., Aberjona River) or appropriate off-site disposal at a permitted
facility, or appropriate approved POTW. Any treatment media contaminated with PCBs will
be tested and disposed of at a TSCA-approved disposal facility. Institutional controls shall
be used to prevent groundwater use until groundwater cleanup levels for PCBs and all other
remedial cleanup levels are achieved.

• Compliance with the PCB regulations at 40 C.F.R. Part 761 will be maintained during all
phases of work involving PCB-contaminated upland soils, wetland sediments/soils, and other
contaminated media including but not limited to: 40 C.F.R. Part 761 Subpart C - Marking of
PCBs and PCB Items; 40 C.F.R. § 761.65 - Storage for Disposal; 40 C.F.R. § 761.79 -
Decontamination Standards and Procedures; and, 40 C.F.R. Part 761 Subpart K - PCB Waste
Disposal Records and Reports.

• A long-term monitoring and maintenance plan shall be developed and implemented for final
compliant caps and for groundwater to ensure effectiveness of the caps in eliminating direct
contact with and ensuring no migration of PCBs from OU4.

G. DATA CERTIFICATION CHECKLIST

The following information is included in the Decision Summary section of this Record of
Decision. Additional information can be found in the Administrative Record file for this site.

1. Chemicals of concern (COCs) and their respective concentrations

2. Baseline risk represented by the COCs

3. Cleanup levels established for COCs and the basis for the levels

4. Current and future land and groundwater use assumptions used in the baseline risk
assessment and ROD

5. Land and groundwater use that will be available at the Site as a result of the selected
remedy

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6.	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

7.	Decisive factor!si that led to selecting the remedy

H. Al TMORI SI GNAT ' R £S

This ROD documents the selected reined} for soil, non-aqueous phase liquid (NAPL),
groundwater, and wetland sed imeiit/so j 1 at SWF (OL'4) portion of the Wells G&ii Superfund
Site This remedy was selected by EPA with concurrence of the Massachusetts Deportment o*'
Hnvironiiiental Protection. A eoov of the Commonwealth's concurrence letter is attached to this
ROD.

U.S. Environmental Protection Agency

Office of Site Remediation and Restoration
Region 1

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Part 2: The Decision Summary

PART 2 - DECISION SUMMARY FOR THE RECORD OF
DECISION

A. SITE NAME, LOCATION AND BRIEF DESCRIPTION

Southwest Properties, Operable Unit 4, Wells G&H Superfund Site

250, 252, 256, 270 and 280 Salem Street, Woburn, MA 01801

CERCLIS ID # MAD980732168

Wells G&H Superfund Site is PRP-lead.

The Southwest Properties (SWP), Operable Unit 4 (OU4), are a portion of the Wells G&H
Superfund Site (Site) located in the City of Woburn in Middlesex County, Massachusetts. The
SWP are approximately 13.3 acres in size and comprise a relatively small portion of the 330-acre
Site. The SWP are comprised of the contiguous properties of land known as the Aberjona
Property 270 & 280 Salem Street; 6.51 acres), Whitney Property (256 Salem Street; 2.67 acres),
and Murphy Property (250 & 252 Salem Street; 4.14 acres). The SWP includes a wetland area
(referred to as the Murphy Wetland; approximately 1.3 acres) that extends along the northern
border of the SWP and into the OU1 Wildwood Source Area Property adjacent to the north. The
Wildwood Source Area Property is one of five source area properties associated with OU1 of the
Site.

The SWP are in a heavily developed commercial and industrial area and area generally buffered
by similarly developed properties. The SWP are bordered to the east by the Aberjona River (on
the eastern side of the Aberjona Property), to the south by Salem Street, to the west by the
Boston and Maine (B&M) Railroad (on the western side of the Murphy Property), and to the
north by the OU1 Wildwood Source Area Property. The SWP are zoned Industrial-Park (I-P) by
the City of Woburn; however, a residence (the Existing Aberjona Residence) is located on the
Aberjona Property. The Existing Aberjona Residence has historically been separated from the
industrial portion of the Aberjona Property by fencing, asphalt pavement, and a concrete wall.
Based on historical information, no industrial operations (e.g., stockpiling of scrap, storage of
materials, automotive repair-related activities) are known to have been performed at the Existing
Aberjona Residence. Parts of the SWP are in the 500-year floodplain as identified by FEMA.
Bordering the SWP to the east, north, and west, the land is zoned Industrial Park (I-P) by the
City of Woburn. Bordering the SWP immediately to the south, the land is zoned Industrial-
General (I-G) by the City of Woburn.

Historical activities at the SWP, including transfer, storage and disposal of waste oil and solvent-
contaminated oil at the Murphy Property, reclaiming and/or reconditioning of drums, tanks and
other metal items at the Whitney Property, and automobile reclamation and storage at the
Aberjona Property resulted in soil and groundwater contamination, as well as wetland
sediment/soil and surface water contamination within the Murphy Wetland. Groundwater is

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found both in the overburden and bedrock formations and generally migrates east-northeast,
towards the Abeijona River.

The Wells G&H Site was listed on the National Priorities List (NPL) on September 14, 1989
with the concurrence of the Governor of Massachusetts.

A more complete description of the Site and the SWP can be found in Section 1 of the Remedial
Investigation (RI) Report (AECOM, 2016a)2.

B. SITE HISTORY AND ENFORCEMENT ACTIVITIES

1. History of Site Activities

The SWP have been utilized for various light industrial operations for nearly 60 years. The
following provides a historical account for each of the three properties comprising the SWP:

• Aberjona Property (270 & 280 Salem Street) - Prior to 1950, the Aberjona Property
operated as a Gulf gasoline station. The Abeijona Property began operations in the mid-
1950s for the sale and reconditioning of used and wrecked automobiles, and was also a
gasoline service station. During operation, the property contained several hundred junked
automobiles, tires, and miscellaneous car parts. Used parts were degreased in a grease pit
located in the floor of the main garage. All waste fluids from the grease pit were
reportedly discharged through a drain to the MDC sewer. An oil-water separator was
connected between the floor drain and the sewer to collect waste oils by gravity
separation prior to discharge to the sewer system. The spent solution in the grease pit was
reportedly picked up by the Murphy Waste Oil Company for reprocessing. In 2007, the
oil water separator was pumped and 160 gallons were shipped off the property for
disposal. The grease pit has not been in use since at least late 1980s. There are also
reports that one to two underground gasoline storage tanks (USTs) existed at the property
from its previous use as a gas station. The USTs were reportedly located south of the
main garage area. The gasoline USTs were removed around 1985. A 500-gallon diesel
UST was formerly located on the northwest corner of the building, and a waste oil tank is
located on the east side of the building. The 500-gallon diesel UST was removed in 2006.
The Abeijona Property continues to operate as an auto repair facility in the main garage
building; however, the auto reclamation business ceased operations in the late 1990's. In
2004 or 2005, several hundred junked vehicles were removed from the northern portion
of the property.

• Whitney Property (256 Salem Street) - From approximately 1950 until 1985, the Whitney
Barrel Company conducted drum and tank recycling and reconditioning activities, with
interior cleaning of drums and exterior cleaning of tanks. Prior to 1950, the property was

2 AECOM, 2016. Remedial Investigation Report, Southwest Properties, Wells G&H Superfund Site; November 2016.

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used primarily for agricultural purposes and unknown storage. Drums, tanks and other
items were brought to the back/north side of the main building, and unloaded either
directly into the main building for processing, or stored in a raw warehouse north of the
main building awaiting processing and/or stored outside the main building awaiting
processing. Large items and tanks were cleaned outside the main building. Drums and
small items were cleaned in wash tanks inside the northern portion of the main building
which discharged into a floor drain. The floor drain was connected to a culvert which
flowed north into the Metropolitan District Commission (MDC)/Massachusetts Water
Resource Authority (MWRA) sewer (via sewer manhole). Sludges that accumulated in a
settling basin connected to the floor drain were periodically collected and taken to the
Woburn Landfill for disposal. Cleaned drums and small items were then painted with
drum enamel paint thinned by solvent. The floor drain was reportedly filled with concrete
and the discharge line to the sanitary sewer was cut and plugged following shutdown of
active drum refurbishing operations circa 1985. Several fires have also reportedly
occurred at the property over the years, the most recent being in 1979, at which time the
main building was nearly destroyed.

• Murphy Property (250 & 252 Salem Street) - The property was used for storage of virgin
oil beginning in the 1920s. By the 1950s waste oils were accepted at the facility. The
operations at the Murphy Property include a transfer, storage and disposal facility for
waste oil and solvent-contaminated oil. In addition, waste oils were placed on the dirt
roadways within the property to control dust until 1979. The northern portion of the
property was formerly known as the "oil yard," and contained as many as 20
aboveground storage tanks (ASTs). Historical information also refers to an area known as
the "oil pit" established in the 1950's in the central portion of the property where spent
waste oil filter media were disposed. Between 1987 and 1990, Clean Harbors performed
a series of investigations in preparation for the property becoming an updated waste oil
handling facility. All of the ASTs in the northern portion of the property were removed
prior to 1989, and approximately 1,100 cubic yards of petroleum-impacted soils were
excavated from the former "oil pit" area in the central portion of the property where new
facility structures were built.

• Murphy Wetland - The Murphy Wetland is located between the upland portions of the
SWP and the Wildwood Source Area Property. Given the location of the former "oil
yard" and "oil pit" at the Murphy property and former barrel washing activities
contributing to impacts within the Northern Whitney Soil Area, historic operational
activities have the potential to have impacted the Murphy Wetland. In addition, the
wetland likely has been impacted by releases originating from neighboring properties
including the former J.J. Riley Tannery to the west (e.g., historic overflows of the
sanitary sewer, discharges from a drainage swale, etc.) and Wildwood Property to the
north (e.g., mixed-contaminated soil impacts), as well as from flood events with the

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potential to redistribute contamination between the Murphy Wetland and the adjacent
properties.

• SWP-Wide Groundwater - Groundwater generally travels across the Murphy, Whitney
and Abeijona Properties to the Abeijona River. Leaching has occurred from the sources
identified at the SWP, where discharge of solvents, PCBs, pesticides, petroleum
hydrocarbons, and possibly other chemicals, has resulted in elevated concentrations of
these constituents in soil and groundwater (both overburden and bedrock) beneath the
SWP.

A more detailed description of the SWP history can be found in Section 1.3 of the 2016 RI
Report and Section 1.2.2 the 2016 Feasibility Study (FS) Report.

2. History of Federal and State Investigations and Response Actions

Table B-l provides a summary of Federal and State Site investigations and removal actions.

Table B-l

Date

Action

Legal
Authority

Who
Undert
ook

Results

Related
Documents

1980

Preliminary Site
Assessments

CERCLA

EPA

FIT Site
Investigation
Reports for
Aberjona and
Whitney
Properties (E&E,
1980)



1988

Site Assessment

Massachusetts
Contingency
Plan (MCP)
21E

PRP

Site Assessment
Report for
Whitney Property
(GHR, 1988)



1986-1988

Remedial
Investigation/
Feasibility Study

CERCLA

EPA

RI Report (NUS,
1986), Final
Supplemental RI
Report (Ebasco,
1988) & Draft
Final Feasibility
Study Report
(Ebasco, 1989)



1988

Site

Investigation

CERCLA

EPA

Sampling Report
(Weston, 1988)



1987-1989

Hydrogeologic
Investigation

MassDEP
RCRAB

PRP

Hydrogeologic
Characterization



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Table B-l

Date

Action

Legal
Authority

Who
Undert
ook

Results

Related
Documents





Permit



Report (Clean
Harbors, 1989)
for Murphy
Property



1989

Short-Term

Remedial

Measure

MassDEP

RCRAB

Permit

PRP

Removal/disposal
of 1,100 cubic
yards of
petroleum-
impacted soil
from Murphy
Property



1993-1994

Remedial
Investigation

CERCLA

PRP

RI Report
(RETEC, 1994)



1995

Hydrogeologic

Investigation

Addendum

MassDEP

RCRAB

Permit

PRP

Hydrogeologic

Characterization

Report

Addendum

(Clean Harbors,

1995) for Murphy

Property



1995,1996

Site

MassDEP

PRP

Corrective Action



& 1998

Investigation

RCRAB
Permit



Report Part I
(1996) and Part II
(1998) for
Murphy Property



2002

Immediate
Response Action

MCP 2IE

PRP

Di scovery/ongoin
g

monitoring/remov
al of NAPL at
Murphy Property
under IRA Plan
(Clean Harbors,
2002)

IRA

Modificatio
ns (February
2003 &
August
2003)and
IRA Status
Reports

2002-2003

Supplemental

Remedial

Investigation

CERCLA

PRP

Supplemental RI
Report (RETEC,
2003)



2004/2006

Baseline Risk
Assessment

CERCLA

EPA

Baseline Human
Health and
Ecological Risk
Assessment

Baseline
Human
Health and
Ecological

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Table B-l

Date

Action

Legal
Authority

Who
Undert
ook

Results

Related
Documents









(updated in 2006)

Risk

Assessment
(2004)

2010-2012

Supplemental

Remedial

Investigation

CERCLA

PRP

Second round of
supplemental RI
activities
conducted

RI Report
(2016)

2013

Vapor Intrusion
Investigation

CERCLA

PRP

Evaluation of
potential vapor
intrusion at the
Existing
Aberjona
Residence

RI Report
(2016)

2013

Well Installation
and Natural
Attenuation
Assessment

CERCLA

PRP

Sampling in
support of MNA
evaluation

RI Report
(2016)

2014

Baseline Risk
Assessment

CERCLA

EPA

Revised Baseline
Human Health
and Ecological
Risk Assessment
Report

RI Report
(2016)

2016

Remedial
Investigation

CERCLA

PRP

Remedial

Investigation

Report

(November 2016)

Revised

Baseline

Human

Health and

Ecological

Risk

Assessment

Report

(2014)

2016

Feasibility Study
Report

CERCLA

PRP

Evaluation of
Remedial
Alternatives
(December 2016)

Revised

Baseline

Human

Health and

Ecological

Risk

Assessment

Report

(2014)

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Table B-l

Date

Action

Legal
Authority

Who
Undert
ook

Results

Related
Documents

2017

Feasibility Study
Report
Addendum -
Technical
Memorandum

CERCLA

EPA

Updated/Revised
Evaluation of
Remedial
Alternatives
(July 2017)

2016

Feasibility
& 2014
Revised
Baseline
Risk

Assessment

Note: The SWP are also listed as three separate MassDEP Bureau of Waste Site Cleanup (BWSC) "Chapter 21-E"
sites. Several Release Tracking Numbers (RTNs; 3-2198, 3-10277, 3-20410, 3-20932, 3-22144, 3-23361, 3-534, 3-
14372 and 3-1146) are on file with the MassDEP for the three properties, the majority of which have reached
regulatory closure under the Massachusetts Contingency Plan (310 CMR 40.0000).

3. History of CERCLA Enforcement Activities

EPA has performed a number of potentially responsible party (PRP) search related activities,
including sending information requests pursuant to CERCLA § 104(e), reviewing files, and
performing record searches. As a result of those PRP search activities, on June 2, 2014, EPA
issued general notice of potential liability letters to the following 16 parties relative to the
Southwest Properties:

1. 280 Salem Street, LLC

2. Beatrice Company

3. Boston Edison Company/NSTAR Electric and Gas Company

4. The Gillette Company

5. Goulston Technologies f/k/a George A. Goulston

6. KEK Realty Trust/John E. Whitney, III and Susan M. Whitney

7. Kingston Steel Drum/Great Lakes Container Corp./Mallinckrodt

8. Lamco Chemical Co.

9. Murphy's Waste Oil Service, Inc.

10. Old Oil Realty Trust

11. Olin Corporation

12. Organix, LLC

13. Samuel Cabot, Inc. c/o Valspar

14. Stepan Company

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15.	Wildwood Conservation Corporation

16.	W.R. Grace & Co.-Conn.

C. COMMUNITY PARTICIPATION

Throughout the Site's history, community concern and involvement has been high. The EPA has

kept the community and other interested parties apprised of Site activities through informational

meetings, fact sheets, press releases, and public meetings. Below is a brief chronology of public

outreach efforts.

•	In April 1986, EPA released a community relations plan which outlined a program to address
community concerns and keep citizens informed and involved in remedial activities.

•	Local residents formed the Aberjona Study Coalition to monitor Site activities. On June 16,
2003, EPA awarded $100,000 Technical Assistant Grant (TAG) to the Abeijona Study
Coalition (ASC) for the Industri-plex and Wells G&H Superfund Sites. ASC has retained a
TAG consultant to review technical documents.

•	Regarding OU4, in May 2014, EPA released a fact sheet describing the contamination and
summarizing the results of the April 2014 baseline risk assessment report. On June 23, 2014,
EPA held a public meeting to present the results of investigation activities conducted at the
SWP, discuss potential risks to human health and the environment and identify next steps for
the SWP, including documentation of data collected and possible cleanup options to be
detailed in the RI/FS.

•	On July 6, 2017, EPA mailed 29 potentially interested party letters and approximately 2,200
public notice postcards to the community announcing the Proposed Plan, July 13, 2017
information public meeting, public comment period from July 14 - August 14, 2017, and
August 3, 2017 public hearing.

•	On July 11, 2017, EPA posted information on the Wells G&H website announcing the
Proposed Plan, July 13, 2017 information public meeting, public comment period from July
14 - August 14, 2017, and August 3, 2017 public hearing.

•	On July 12, 2017, EPA issued a press release and on July 14, 2017 EPA published a notice in
the Woburn Daily Times and Boston Globe newspaper announcing the Proposed Plan, July
13, 2017 information public meeting, public comment period from July 14 - August 14,
2017, and August 3, 2017 public hearing.

•	On July 13, 2017, EPA made the administrative record and the Agency's Proposed Plan
available for public review at EPA's offices in Boston and at Woburn Public Library, 45
Pleasant St, Woburn, MA. This will be the primary information repository for local residents
and will be kept up to date by EPA. EPA also made the administrative record and the
Agency's Proposed Plan available for the public review online through the internet at

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https://go.usa.gov/xNFws. The Proposed Plan included the following determinations: the
proposed cleanup action activities that impact wetlands are the Least Environmentally
Damaging Practical Alternatives as defined by Section 404 of the federal Clean Water Act
and regulations promulgated under the statute; the proposed cleanup action activities that
impact floodplains are to avoid or minimize potential harmful temporary and permanent
impacts on floodplain resources within the 500-year floodplain to the extent practical, and
any lost flood storage capacity from cleanup activities within the floodplain would be
addressed as appropriate in compliance with regulatory requirements at 44 C.F.R. Part 9 and
Executive Order 11988 (Floodplain Management); and consistent with Section 761.61(c) of
TSCA, EPA has determined that the disposal of PCB contaminated material as described in
the Administrative Record for this cleanup plan does not result in an unreasonable risk of
injury to human health or the environment as long as certain conditions are met.

•	On July 13, 2017, EPA held an informational meeting to discuss the results of the 2016
Remedial Investigation and the cleanup alternatives presented in the 2017 Feasibility Study
Report Addendum - Technical Memorandum, 2016 Feasibility Study Report, and to present
the Agency's Proposed Plan to a broader community audience than those that had already
been involved at the Site. At this meeting, representatives from EPA answered questions
from the public.

•	From July 14, 2017 to August 14, 2017, EPA held a 30-day public comment period to accept
public comment on the alternatives presented in the 2017 Feasibility Study Report
Addendum - Technical Memorandum, 2016 Feasibility Study Report, and the Proposed Plan
and on any other documents previously released to the public. An extension to the public
comment period was requested, and, as a result, the comment period was extended to
September 13, 2017 (see August 10, 2017 published notice below).

•	On August 3, 2017, the Agency held a public hearing to discuss the Proposed Plan and to
accept any oral comments. A transcript of this meeting and the comments and the Agency's
response to comments are included in the Responsiveness Summary, which is part of this
Record of Decision.

•	On August 10, 2017, EPA posted information on the Wells G&H website announcing an
extension to the Proposed Plan comment period to September 13, 2017.

•	On August 14, 2017, EPA mailed 29 postcards to potentially interested parties announcing an
extension to the Proposed Plan comment period to September 13, 2017.

• On August 18, 2017, EPA published a notice announcing an extension to the Proposed Plan
comment period to September 13, 2017 in the Woburn Daily Times and Boston Globe
newspaper.

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• On August 21, 2017, EPA issued a press release announcing an extension to the Proposed
Plan comment period to September 13, 2017.

• All public comments received during the public comment period have been address by EPA
in the attached Responsiveness Summary (Part 3 of this document).

D. SCOPE AND ROLE OF OPERABLE UNIT OR RESPONSE ACTION

As with many Superfund sites, the problems at the Wells G&H Superfund Site are complex. As a
result, EPA has organized the work into four operable units (OUs):

• OU1: Includes contaminated groundwater, soil, and sludge found at the five properties (i.e.,
W.R. Grace and Co., Inc. [Grace Source Area Property], UniFirst Corporation [UniFirst
Source Area Property], Olympia Nominee Trust [Olympia Source Area Property], Wildwood
Conservation Corporation [Wildwood Source Area Property], and New England Plastics
Corporation [NEP Source Area Property]) identified as sources of contamination at the Site.

• OU2: The Central Area (OU2) contains three other geographic areas including the Central
Area Aquifer, the Eastern Uplands, and the Northeast Quadrant. RI/FS activities were
previously conducted at the SWP under OU2.

• OU3: The Aberjona River Study (OU3) was designed to investigate the nature and extent of
contamination in the Aberjona River sediments and surface water.

• OU4: Includes contaminated groundwater, soil and wetland sediments/soils, as well as the
presence of NAPL observed at the SWP.

The EPA selected the remedy for OU1 in the 1989 ROD. The 1991 Explanation of Significant
Differences documents changes to the 1989 ROD. Under the 1991 Consent Decree between
EPA and the settling defendants for the Site, the settling defendants agreed to clean up four of
the five OU1 source area properties.

OU1 includes contamination source control and management of migration components, and is
currently in the remedial design/remedial action phase, with construction completed at four of
the source area properties.

The selected remedy for OU1 includes the following source control measures:

• Excavation and on-site incineration of approximately 2,100 cubic yards of contaminated soil.
Excavated areas will be backfilled.

• In situ volatilization of approximately 7,400 cubic yards of contaminated soil, part of which
is located in a wetlands area. In situ treatment will use carbon adsorption for vapor treatment.

The OU1 management of migration remedial measures include:

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• Pumping contaminated groundwater from the overburden and/or bedrock aquifers,
pretreatment to remove suspended solids and metals, and treatment by air-stripping to
remove contaminants. Carbon adsorption will be used to treat emissions from the air stripper.

• Groundwater will be treated at separate source area treatment plants.

• Groundwater will be pumped with the objective of achieving Safe Drinking Water Act
Maximum Contaminant Levels in the aquifer.

Additional measures in the OU1 remedy include:

• The removal and disposal of approximately 410 cubic yards of sludge and debris.

Also, under two separate Administrative Orders by Consents (AOCs) signed in 2003 and 20043,
the settling defendant for the Olympia Nominee Trust property agreed to clean up the fifth
source area property.

The second operable unit (OU2), also referred to as the Central Area, was identified by EPA in
the 1989 ROD as an area requiring further evaluation. OU2 is comprised of the area between the
five OU1 source area properties, including the SWP, but not including the Abeijona River. The
1991 settling defendants agreed to conduct the RI/FS for the Central Area.

EPA investigated the surface water and sediment associated with the Aberjona River, which
flows through the Site, as the third operable unit (OU3). The Aberjona River also flows through
the Industri-plex Superfund Site, located approximately 1 mile upstream of the Wells G&H Site.
In 2006, EPA issued a cleanup decision for the Aberjona River for both the Industri-plex and
Wells G&H sites known as the Industri-plex Operable Unit 2 (including Wells G&H Operable
Unit 3, Abeijona River Study) ROD.

The SWP is located in the southwest portion of OU2. OU2 contains three other geographic
areas: the Central Area Aquifer, the Eastern Uplands, and the Northeast Quadrant. The RI/FS for
the Central Area is described in Appendix II of the 1991 Consent Decree, Statement of Work
(SOW) Wells G&H Superfund Site.

RI work was undertaken in the Central Area by GeoTrans, Inc. of Harvard, Massachusetts
(GeoTrans) on behalf of the OU1 Settling Defendants (e.g. W.R. Grace & Co., Beatrice
Company (Beatrice), UniFirst Corporation, and New England Plastics. This joint RI work
included background information on the SWP. The initial phase of the RI was conducted in the
Central Area in 1992 to 1993, and submitted to EPA in February 1994 (known as Phase 1A RI).
The Phase 1A RI, Attachment 1, included a separate RI for the SWP prepared by Beatrice, dated
February 1994. This separate RI for the SWP was supplemented with an August 2003 RI report
by Beatrice. Following this work, EPA issued a Baseline Human Health Risk Assessment (BRA)

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for the SWP in March 2004, which was later updated in February 2006. This work necessitated
a third phase of RI activities at the SWP in 2010 to 2013, including additional groundwater and
soil samples. A final BRA for the SWP was issued by EPA in 2014 (EPA, 2014). A RI Report
(November 2016) and FS Report (December 2016) were submitted by Beatrice Company. EPA
then prepared an FS Report Addendum - Technical Memorandum (July 2017) for the SWP.
Under this ROD, the SWP cleanup has been designated as Operable Unit 4 (OU4). Additional
investigation activities are still on-going for the Central Area Aquifer (OU2) and a remedy will
be selected following the completion of the OU2 RI/FS, including a BRA for groundwater
exposures.

OU4, the subject of this ROD, addresses the contamination of the groundwater, soil and wetland
sediments/soils, as well as the presence of NAPL, within the SWP. This ROD addresses
groundwater, soil, and wetland sediment/soil contamination. Ingestion of water extracted from
the overburden and bedrock aquifers poses a future potential risk to human health because EPA's
acceptable risk range is exceeded and concentrations of contaminants are greater than the
Maximum Contaminant Levels for drinking water (as specified in the Safe Drinking Water Act).
Migration of contaminated groundwater also poses a risk to the human health and the
environment within the OU's wetlands. Exposure to soils across the SWP also poses a future
risk to human health, and exposure to wetland sediments/soils and NAPL poses a current and
future risk to human health and the environment. This ROD presents a comprehensive remedy
for the SWP and addresses the principal threat at the SWP through excavation and off-site
disposal.

The principal and low-level threats that this ROD addresses are summarized in the following
table:

Principal
Threat Wastes

Contaminant(s)

Action To Be Taken

NAPL and
Northern
Whitney Soil
Area Source
Soils

VOCs, PCBs,

Pesticides,

PAHs,

Petroleum

Hydrocarbons,

Metals

Excavati on/Off- Site
Disposal

Low-Level
Threat Wastes

Contaminant(s)

Action To Be Taken

Site-wide Soils
and Wetland

VOCs, PCBs,
Pesticides,

Capping for Site-wide
Soils, including

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Sediments/Soil

PAHs,

excavations and off-site

Petroleum

disposal of soils to

Hydrocarbons,

facilitate capping;

Metals

Excavati on/Off- Site

Disposal for Wetland

Sediment/Soil

E. SITE CHARACTERISTICS

Section 1 of the Feasibility Study contains an overview of the RI. The significant findings of the
RI are summarized below.

The chemicals of concern (COCs) are summarized in Tables G-l through G-4 for surface and
subsurface soil, wetland sediment/soil, and groundwater, respectively, detected chemicals are
presented in Table 4-6 of the 2016 RI for Non-Aqueous Phase Liquid or NAPL. NAPL is free
product material (e.g., waste oil, certain solvents) that is found in soil or groundwater due to its
historic release at the ground surface and its migration into the subsurface. The NAPL observed
in monitoring wells at the SWP is floating free product or globules. The COCs include but are
not limited to the following:

VOCs or Volatile Organic Compounds include a variety of chemicals that are used in glue,
paint, solvents, and other products and easily evaporate. Common VOCs include trichloroethene
(TCE), cis-l,2-dichloroethene (cis-l,2-DCE), and tetrachloroethene (PCE). These compounds
are found in SWP groundwater and to some extent in NAPL and soil.

Petroleum Hydrocarbons are mixtures of aliphatic and aromatic compounds composed of
hydrogen and between five and 36 carbons. Gasoline, fuel oil, and waste oil are examples of
petroleum hydrocarbon mixtures. Due to the historic use and releases of petroleum products at
the SWP, petroleum hydrocarbon fractions are found in groundwater and wetland sediment/soil.
NAPL on the Whitney and Murphy Properties is composed primarily of petroleum compound
mixtures.

SVOCs or Semi-Volatile Organic Compounds are chemicals that may vaporize when exposed
to temperatures above room temperature. The SVOC naphthalene is present in SWP
groundwater and NAPL.

PCBs or Polychlorinated Biphenyls are manmade chemicals that were used in electrical
manufacturing and were banned in 1979. They are persistent in the environment. Analytical
data were collected for total PCBs and for dioxin-like PCBs, specific congeners of PCBs that
display similar toxic effects to dioxin). The Whitney Property and the Murphy Property have
been contaminated with PCBs due to historic waste oil handling and disposal practices. PCBs
have been identified in soil, NAPL, and groundwater. Wetland sediments/soils have been
contaminated with PCBs due to runoff and groundwater discharge from the adjacent uplands.

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Pesticides are manmade chemicals used for the elimination of unwanted animal, insect and plant
pests. Although they are designed to target non-human pests, they can also produce adverse
health effects in humans. Many pesticides are also persistent in the environment. Due to the
historic barrel washing activities that occurred at the Whitney Property, pesticides are present in
soil, wetland sediments/soils, and SWP groundwater.

Metals are minerals that naturally occur in the Earth's crust, and may be mobilized by industrial
activities or releases. Metals present in the soils, wetland sediments/soils, groundwater and
NAPL at the SWP include arsenic, lead, chromium, manganese, and others.

1. Conceptual Site Model

The Conceptual Site Model (CSM) for contaminated soil, wetland sediment/soil, and
groundwater at the SWP is provided in Figure E-l. The CSM is a three-dimensional "picture"
of site conditions that illustrates contaminant sources, release mechanisms, exposure pathways,
migration routes and potential human and ecological receptors. Potential human and ecological
receptors are presented in Section G of this ROD. The CSM documents current and potential
future conditions and shows what is known about human and environmental exposure through
contaminant release and migration to potential receptors. The risk assessment and response
action for the contaminated soil, groundwater, NAPL, and wetland sediment/soil at the SWP are
based on this CSM.

For the purposes of the RI, the SWP was organized into the following four areas, along with
SWP-wide groundwater. The areas, including their primary sources and impacted media, are
discussed below:

Aberjona Property - The property was operated from the mid-1950s to the late 1990s as an auto
reclamation, used parts and car storage area. The following primary sources of contamination
have been identified at this property:

• Historical storage and burning of junk cars;

• Gasoline and waste soil USTs;

• Degreasing operations and releases of VOCs to an oil/water separator via a floor drain before
discharge to the sanitary sewer; and

• Incidental releases (e.g., fluids from junk autos and dismantled auto parts).

Soil was the impacted media by the contaminants released from the primary sources. The
contaminants in soils at the Aberjona Property are primarily VOCs, petroleum hydrocarbons,
SVOCs, and metals.

Whitney Property - The property was operated as a drum, tank, and machinery reconditioning
facility from approximately 1950 until 1985. The following primary sources of contamination

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have been identified at this property:

•	Discharge of drum waste and cleaning fluids into a floor drain (connected to the
MDC/MWRA sewer);

•	Direct releases (VOCs and oil/grease) to an MDC sewer manhole;

•	Historic activities and storage practices leading to direct release of drum waste onto the
ground; and

•	Various building fires releasing petroleum or other hazardous substances.

NAPL has been identified in the subsurface at this property (refer to Figure E-2). Soil, wetland
sediments/soils and groundwater were the impacted media by the contaminants released from the
primary sources. The contaminants in soils at the Whitney Property are primarily VOCs,
petroleum hydrocarbons, SVOCs, PCBs, pesticides, and metals.

Murphy Property - The property was used to store virgin oil beginning in the 1920s and in the
1950s, waste oils were accepted at the facility. The following primary sources of contamination
have been identified at this Property:

•	"Oil yard" waste oil and solvent-contaminated oil ASTs;

•	Disposal of waste oils and solvent-contaminated oil in the "oil pit";

•	Historic spills of fuel oil and reclaimed oil; and

•	Direct application of waste oils onto dirt roads to suppress dust.

NAPL has been identified in the subsurface at the Murphy Property (refer to Figure E-2). Soil,
wetland sediments/soils, and groundwater were the impacted media by the contaminants released
from the primary sources. The contaminants in soils at the Murphy Property are primarily
VOCs, petroleum hydrocarbons, SVOCs, PCBs, and metals.

Murphy Wetland - While this wetland was not used for commercial operations, it received
contamination from sources on adjacent upland areas including, but not limited to:

•	NAPL from the Murphy Property oil yard and oil pit;

•	Sanitary sewer overflows;

•	Periodic flooding of the adjacent Murphy and Whitney Properties, which likely released
contamination to the wetland;

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•	Overland runoff from rainfall events which transported contamination associated with
surficial soils and spills to the wetland;

•	Drainage in a swale directly from the former John J. Riley Tannery property that caused
sediment deposition in the northern portion of the wetland by the railroad culvert;

•	Breaks in the MDC sewer line leading from the Whitney Property building; and

•	Discharge of contaminated groundwater.

The contaminants in wetland sediment/soil at the Murphy Wetland are PCBs, VOCs, petroleum
hydrocarbons, and metals.

SWP-wide Groundwater - Groundwater flow is generally from southwest to northeast across the
Murphy, Whitney and Abeijona Properties of the SWP towards the Abeijona River. The above
Murphy Property, Murphy Wetland, Whitney Property and Aberjona Property contribute to
groundwater impacts across the SWP.

The major aspects of the CSM for the SWP are as follows:

Primary Release Mechanisms - Spills, releases, and other operational incidences led to the
release of contamination onto the surface soil. Former USTs, the oil pit, and releases to
drain/sewer lines led to the release of contamination in the subsurface soils and groundwater.
The spills and releases resulted in NAPL formation in the subsurface at the Murphy and Whitney
Properties. Once the soils were contaminated and NAPL was present, the contamination
migrated to other media in a variety of ways. The most likely primary routes of migration
include the following:

Primary and Secondary Transport Mechanisms - The most likely primary routes of migration
include the following:

•	Leaching to Groundwater - Leaching moves surficial contamination from surface and
subsurface soils to the groundwater. In addition, contaminants in NAPL may dissolve into
groundwater on the Murphy and Whitney Properties. The groundwater, on a site-wide basis,
has been contaminated by several metals, VOCs, petroleum hydrocarbons, SVOCs,
pesticides, and PCBs. Leaching may occur as a result of precipitation or flooding for VOCs
and petroleum fractions. Some contaminants, such as organic compounds with low organic
carbon partitioning coefficient (Koc) factors, may be more likely to be present in porewater of
the soils, making leaching of these compounds a preferential pathway;

•	Volatilization to Soil Gas - VOCs released to the soils and groundwater may cause VOC
release to the soil gas by volatilization under buildings or within a trench excavation and may
potentially enter buildings or trenches if present;

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• Preferential Migration Pathways - The potential exists for utilities, drains, etc. to act as
preferential groundwater pathways at the SWP. Structural features including the presence of
impermeable surfaces (e.g., pavement, buildings, etc.) and utilities and associated bedding
material (e.g., MWRA sewer line) can locally influence the shallow groundwater system.
Subsurface utilities, including water lines, sewer lines and storm drains, can provide
preferential pathways for groundwater flow, creating localized discharge points, as well as
soil gas migration;

• Physical Processes - Contaminants in soils can be moved directly via the movement and
placement of soils. Overland flow that may occur during flooding that may suspend soils or
sediment and create a re-distribution of these materials and the associated contaminants.
Runoff and erosion processes occurring during weather events, such as rain or wind, may
move surficial soils and associated contaminants overland towards lower areas (e.g., the
Murphy Wetland). From these processes, soils and sediments not directly part of the
operations or release areas may be impacted; and

• Groundwater/NAPL Discharge - Contaminated groundwater and NAPL may also discharge
into the Murphy Wetland area as seeps and can produce sheens. Seeps are direct discharge of
groundwater to shallow wetland sediment/soils. In general, the potential discharge of
groundwater to the Murphy Wetland area may occur primarily from the Murphy Property.

2. Site Overview

The Site is comprised of a 330-acre triangular shaped tract of land within the Abeijona River
Valley bounded by Route 128/Interstate 95 to the north, the Boston & Maine (B&M) Railroad
right-of-way to the west, and Salem Street, Cedar Street, and Interstate 93 to the south (Figure
A-l). The Central Area (OU2) is comprised of the area between the five OU1 source area
properties, not including the Aberjona River. The SWP (OU4) are located in the southwest
portion of the Site near the intersection of Salem Street and the B&M Railroad right-of-way.

The SWP are approximately 13.3 acres in size and comprises a relatively small portion of the
330-acre Site. The SWP are comprised of contiguous properties of land known as the Abeijona
Property, Whitney Property, and Murphy Property as shown on Figure E-3). The SWP includes
a wetland area (referred to as the Murphy Wetland; approximately 1.3 acres) that extends along
the northern border of the SWP and into the Wildwood Source Area Property adjacent to the
north.

The SWP are bordered to the east by the Abeijona River on the eastern side of the Abeijona
Property, to the south by Salem Street, to the west by the B&M railroad on the western side of
the Murphy Property, and to the north by the Wildwood Source Area Property.

The SWP are located in a heavily developed commercial and industrial area. The three
properties themselves are zoned Industrial Park. A residence is located on the Aberjona Property.
The Murphy Wetland, comprised of a seasonally ponded area and a forested/scrub-shrub wetland

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area and intermittent stream, extends along the northern border of the SWP between the Murphy
/ Whitney Properties and the Wildwood Property to the north, and it also extends partway
between the Murphy and Whitney Properties (Figure E-3). Much of the SWP are also in the
500-year floodplain as identified by FEMA as shown on Figure E-4.

To the west of the B&M railroad tracks is the former John J. Riley Tannery site, which was once
part of the former John J. Riley leather tannery. This property is located uphill from the SWP and
is connected to the Murphy Wetland by a stormwater culvert that passes beneath the railroad
tracks and discharges into the Murphy Wetland (Figure E-3).

The Abeijona Property continues to operate as an auto repair facility in the main garage building,
with an automotive storage area and a fence-enclosed-locked dog exercise facility is located in
the northern portion of the property. A house (the Existing Aberjona Residence) is also present in
the southeast portion of the Abeijona Property bordering the Abeijona River and Salem Street.

Additional surface features include mature vegetation and trees line the northern property
boundary along each property within the SWP, with open central areas that accommodate
various work activities at each property. Trunk lines for the City of Woburn and MWRA sanitary
sewers run along the access road between the Whitney and Abeijona Properties (Figure E-3). In
addition, a City of Woburn sanitary sewer and easement is present at the Murphy Property. The
sewer runs across the northern section of the SWP in an east/west direction and connects with the
sewer line running down the access road to the Wildwood Source Area Property and connecting
to the sewer under Salem Street (Figure E-3). The sewer line originates to the west of the
Murphy Property within the former John J. Riley Tannery property.

Topography

The topography of the SWP slopes gently from the west to the east towards the Abeijona River.
Elevations across the SWP range from approximately 38 feet above mean sea level (msl) in the
localized wetland area between the Murphy and Whitney Properties to approximately 70 feet
above msl in the southwest corner of the Murphy Property. Bedrock outcrops are present along
the western boundary of the Site in the vicinity of the SWP. The major drainage features in the
vicinity of the SWP include the wetland intermittent stream that borders the northern edge of the
SWP, and the Abeijona River along the eastern boundary of the SWP.

Geology

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The Central Area (OU2) and SWP (OU4) portions of the Wells G&H Site are underlain by
unconsolidated Pleistocene glacial deposits that overlie crystalline bedrock. The sequence of the
unconsolidated deposits from the bedrock to the ground surface includes a combination of
glacially deposited lodgment and ablation tills overlain by stratified drift deposits overlain by
more recent swamp/fluvial deposits and anthropogenic fill. The fill is typically comprised of
light-gray to dark-brown sand mixed with subangular gravel and silt and in some areas contains
varying amounts of ash, brick, metal, plastic and/or wood debris.

Bedrock at the SWP is comprised primarily of granodiorite characterized as the Salem
Granodiorite, the Dedham Granite, and undifferentiated metavolcanics. A bedrock valley
underlies the SWP area and trends roughly north-south, rising steeply from the base of the valley
to the east towards the intersection of Washington Street and Route 128. Published data notes
that the region is cut by numerous faults, formed and commonly re-activated over a long period
of time, mostly trending northeast and east. There appears to be no systematic orientation of the
bedrock fractures at these locations. Fractures/fracture zones may exist locally within the Wells
G&H Site and these fractures/fracture zones may preferentially control groundwater flow and
migration of contaminants in the bedrock groundwater system. Bedrock data from SWP indicate
that the bedrock is competent, however, localized fracture zones may be present that may yield
low volumes of water and may serve as migration pathways.

Hydrogeology

Groundwater at the SWP originates directly via local rainfall recharge as well as rainfall recharge
originating outside the SWP boundary and flowing on to the SWP. Groundwater exits the SWP
via discharge to the local wetlands and surface water bodies, in particular, the Abeijona River.
Under non-pumping conditions, regional groundwater flow directions are generally toward the
Aberjona River. Near the center of the valley, groundwater flow converges toward and
discharges to the Abeijona River. With respect to the SWP, groundwater flow under non-
pumping conditions is generally to the east, towards the Abeijona River in both unconsolidated
soils and shallow bedrock. Conceptually, vertical hydraulic gradients are typically downward on
the valley flanks and upward in the center of the valley. The upward hydraulic gradients in the
central portion of the valley indicate groundwater discharge into the Abeijona River and
associated tributaries and wetlands.

3. Remedial Investigation Sampling Strategy

An extensive sampling effort was completed to support the RI, BRA and FS for the SWP.
Physical and analytical data have been collected to develop the CSM and identify the nature and
extent of SWP-related constituents in the environment. Several phases of investigation have been
conducted at the SWP as follows:

Remedial Investigation (1994) - The first phase of RI work was conducted in accordance with
the EPA approved RI/FS Work Plan for OU2 of the Wells G&H Site. The RI for OU2 was
undertaken by several of the settling defendants (Beatrice, UniFirst Corporation and W.R. Grace

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& Co.), and included the SWP. In addition, a separate RI was undertaken by Beatrice which
specifically addressed the SWP. The results of this work were reported in a Draft RI Report
dated February 1994. The RI determined that the principle environmental concerns on the SWP
were attributed to the industrial operations conducted on the three properties. Specifically, the
Aberjona Property had groundwater contamination likely related to the use of solvents and
degreasers. The Whitney Property had widespread, low level concentrations of VOCs, PCBs and
pesticides in soil and groundwater. The Murphy Property had petroleum contaminated soils and
groundwater impacted by VOCs (e.g., 1,1-dichloroethene and TCE) at concentrations above the
Safe Drinking Water Act (SDWA), Maximum Contaminant Levels (MCLs).

Murphy Property RCRA B Permit-related Investigations - A number of investigation activities
have been conducted at the Murphy Property (250 & 252 Salem Street) since the early 1980s.
These activities include several phases of RCRA Corrective Action Investigations between 1988
and 1998, performed pursuant to the RCRA Part B Permit issued to Murphy's Waste Oil Service,
Incorporated by the Commonwealth. Activities included installation of borings and monitoring
wells, soil and groundwater sampling, and wetland sediment/soil sampling in the Murphy
Wetland.

Results of the investigation activities at the Murphy Property verified findings of previous
investigations which identified oil-impacted soils primarily in the area of the former "oil pit" in
the central portion of the property and the area of the former ASTs in the northern portion of the
property. Elevated concentrations of COCs, including petroleum compounds, PAHs and VOCs,
were detected throughout these portions of the property. In addition, elevated concentrations of
VOCs in groundwater were confirmed at the Murphy Property. Sampling of wetland
sediments/soils confirmed and helped to delineate the distribution of petroleum compounds,
PCB, lead, and chromium impacts.

In addition, other limited investigations have been conducted under the MCP from 2001 to the
present at the Murphy Property. MCP Immediate Response Action (IRA) activities include
NAPL measurements and removal (when encountered). The presence of NAPL is related to
historic operations at the facility, including the use of the "oil pit" for disposal of spent waste oil
filters and/or as a result of releases of waste oil from the former AST area ("oil yard"). During
the 2001 to 2015 period, the maximum levels of NAPL product measured in monitoring wells by
Clean Harbors on the Murphy Property includes 1.80 ft at MW-7, 1.43 ft at MW-16, 0.01 ft at
MW-23, 3.40 ft MW-24 and 0.44 ft at MW-25. During the period of July 2014 to July 2015,
NAPL thicknesses were observed in wells MW-16 (up to 1.16 ft), MW-24 (up to 2.30 ft), and
MW-25 (up to 0.17 ft).

Supplemental Remedial Investigation (2002 to 2003) - At the request of EPA, additional
investigation activities were performed to update and supplement information regarding the SWP
and collect additional data in support of the BRA. The results were reported in the Supplemental
Remedial Investigation Report dated August 2003 (Supplemental RI). The Supplemental RI
concluded that the distribution of chemicals in the subsurface was consistent with the history of

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commercial use at the SWP. Areas of former commercial activity, such as the waste oil storage
and transfer at Murphy Property, the barrel refinishing at Whitney Property, and the auto junk
yard and repair facility at Aberjona Property, were confirmed as likely or potential source areas.
Areas where no past commercial use occurred were used to evaluate background conditions. The
Supplemental RI also confirmed that primary COCs in soils, wetland sediments/soils and
groundwater at the SWP included VOCs, petroleum hydrocarbons, PAHs, pesticides, PCBs and
metals.

Following completion of the Supplemental RI and making use of data collected prior to 2002, a
Baseline Human Health Risk and Ecological Risk Assessment was prepared for SWP in March
2004. Due to an error, the 2004 Baseline Human Health Risk Assessment was revised and
"page-changes" to correct the error were published in February 2006.

Supplemental Remedial Investigation (2010 to 2013) - In response to EPA's May 14, 2009 draft
comment letter on the August 2003 Supplemental RI for the SWP, additional investigation and
evaluation activities were conducted at the SWP between 2010 and 2013 to further delineate the
extent of impacts and further support the BRA. The primary objectives of the Supplemental RI
were to address data gaps identified by EPA in previous investigation activities and evaluate
current contaminant conditions at the SWP.

As part of the Supplemental RI work, NAPL samples were collected on December 21, 2012 from
wells MW-16, MW-24 and MW-25 for analysis of VOCs, VPH/EPH, TPH, PCB congeners,
petroleum fingerprinting, density and viscosity. For the petroleum finger printing, the majority of
the material detected within the samples eluted within the C20-C38 oil range organic (ORO)
range. The pattern of the material detected closely resembled the motor oil reference standard
used for calibration. Considering the concentrations of various compounds within NAPL (such
as 1,2-cis-DCE at 1,500,000 |ig/kg, PCBs at 282,000 ng/g, naphthalene at 1,200,000 |ig/kg, and
CI 1-C22 aromatic hydrocarbons at 84,200 |ig/kg), the NAPL at the Murphy Property likely
contributes to VOC, PCB, SVOC and petroleum impacts in groundwater and the adjacent
Murphy Wetland.

A further evaluation of potential vapor intrusion was conducted at the Abeijona Residence in
accordance with an EPA approved Vapor Intrusion Assessment Work Plan in 2013. The
investigation activities included a building survey to document the condition of the foundation,
building materials, heating, ventilating and air conditioning (HVAC) systems if any, any
preferential vapor migration pathways, and to inventory any chemical products stored at the
property. Sub-slab soil vapor, indoor air, and ambient air samples were collected in April and
August 2013.

During 2013, additional well installation and a Monitored Natural Attenuation (MNA)
investigation was also conducted at the SWP in accordance with an EPA approved Revised
Work Plan for Installation of Monitoring Wells and Monitored Natural Attenuation Groundwater
Sampling. The supplemental investigations were conducted to evaluate the potential for natural

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attenuation processes to be occurring at the SWP, to further evaluate NAPL composition, and to
further characterize bedrock conditions. The data presented in this RI were used to develop a
detailed analysis and evaluation of potential remedial alternatives that are presented in the
accompanying revised Feasibility Study (AECOM, 2016) to address areas of unacceptable
human health or ecological risk.

4. Nature and Extent

Consistent with previous environmental investigation activities conducted at the SWP, the
following summarizes the nature and extent impacts (organized by media):

• Soils - The delineation of soil contamination is generally defined by the horizontal and

vertical extent of COCs at concentrations greater than the cleanup levels in Table L-2 and as
shown on Figures E-5, E-6 and E-7. The COCs in soils include metals, VOCs, petroleum
hydrocarbon fractions, SVOCs, pesticides, and PCBs. Areas of elevated metals are primarily
associated with:

o The area behind the Whitney Property adjacent to the former drum washing

operations area and along the former drain line (Northern Whitney Soil Area); and

o At the Murphy Property, in and around the former waste oil AST area and the former
oil pit.

Metals concentrations generally decreased with depth, with the exception of lead and
thallium at the Murphy Property which had higher concentrations in soil samples
collected from 6 to 15 ft bgs in the area of the former oil pit. The pattern of VOC
concentrations appears to primarily be associated with the former drum washing
operations area at the Whitney Property and the former waste oil AST storage area
(known as the "oil yard") and the former oil pit area at the Murphy Property. As with
VOCs, the distribution of petroleum hydrocarbon fractions at the Whitney Property are
primarily associated with the former drum washing operations area and along the former
drain line. At the Murphy Property, petroleum hydrocarbon fraction impacts are
associated with the former waste oil AST storage area and the former oil pit area. At the
Aberjona Property, petroleum hydrocarbon fraction impacts are associated with the
former 500-gallon diesel UST at the northeast corner of the main building, near the
former floor drains and waste oil tank on the east side of the building, and the area
immediately to the north of the main building. The distribution of dieldrin, representative
of pesticide impacts, indicates that the distribution of pesticides is correlated with the
former drum washing operations area and floor drain at the Whitney Property. Similarly,
the distribution of PCBs shows a clear correlation to the former drum washing operations
area and floor drain line on the Whitney Property and with the former waste oil AST area
at the Murphy Property where an historical release of oil was documented.

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•	Wetland Sediments/Soils - The extent of contamination in wetland sediments/soils (Figure
E-8) is largely defined by areas where chromium, lead, and PCBs, and to a lesser degree
concentrations of zinc and C11-C22 aromatic petroleum hydrocarbon fraction, exceed human
health and/or ecological cleanup levels in Tables L-3 and L-4, respectively. The source of
the elevated chromium in the wetlands is likely attributed to a combination of historical
erosion from the Murphy and Whitney Properties, historic sewer overflows within the
wetland north of the Murphy Property, and deposition from erosion of the drainage swale at
the former John J. Riley Tannery property, and the erosion of fill that is located over the
entire surface of the SWP. The presence of lead and PCBs in wetland sediments/soils is
attributed to the presence of historic runoff from the Whitney Property and the Murphy
Property and the presence of NAPL at the Murphy Property near the wetland that
occasionally results in visible sheen on the surface water in the wetlands.

•	Surface Water - Surface water is present intermittently in wetland portions of the SWP.
Aluminum, chromium, cobalt, iron, manganese and total cyanide were detected above human
health and/or aquatic life screening levels. The highest concentrations of chromium and
manganese were at the northeast corner of the Murphy Property. The highest concentration of
iron was found at the western edge of the finger of the Murphy Wetland that extends between
the Murphy and Whitney Properties. The highest concentration of cyanide was found in the
wetland north of the Murphy Property.

•	Groundwater - In general, the extent of groundwater contamination within the shallow
overburden, intermediate/deep overburden and shallow bedrock is limited to areas of the
SWP where concentrations of COCs in groundwater exceed MCLs or risk-based cleanup
levels in Table L-l. The overarching patterns of detections of metals, VOCs, SVOCs,
pesticides, and PCBs correlated with known historical operations, historical practices,
historical events, and elevated soil concentrations at the SWP including:

o The former waste oil AST area and the former oil pit area at the Murphy Property,
characterized by wells MW-16, MW-18S, MW-24, MR 206, and MW-7;

o The former drum washing operations area and former floor drain line at the Whitney
Property, characterized by a number of wells immediately to the north and east along
the downgradient property boundary with the Abeijona Property (i.e., Northern
Whitney Soil Area); and

o The central portion of the Aberjona Property and main building operations area
characterized by the AB-2 well cluster and adjacent wells.

Across the SWP, CVOCs were the predominant contaminants detected in groundwater
above their MCLs (or lowest TCL if an MCL does not exist). At the Murphy and
Whitney Properties, petroleum fractions and other VOCs and SVOCs (e.g., benzene,
benzo(a)anthracene, and naphthalene) were also found in groundwater above their MCL /
lowest TCL. In addition, at the Whitney Property various pesticides (e.g., aldrin and
dieldrin) and PCBs were found in groundwater above their lowest TCLs. Various metals

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were found in SWP groundwater, with arsenic detected behind the Whitney Building at
concentrations greater than its MCL. Lead was detected above its action level at the
Murphy Property in wells MW-16, MW-18S, MW-24, which are located in the area
where NAPL has been observed.

Although there are exceedances of cleanup levels in the shallow bedrock, primarily for
VOCs, there is a general decline in concentrations with depth consistent with vertical
gradient data (typically upwards) at the SWP. This indicates that vertical gradients are
favorable for limiting vertical downward migration and/or that contaminants are
degrading with distance from sources (both horizontally and vertically). The groundwater
contaminant plumes within the shallow overburden, intermediate/deep overburden and
shallow bedrock portions of the aquifer are depicted in Figure E-9. The shallow
overburden plume generally extends east-northeast from the former "oil pit" and "oil
yard" portions of the Murphy Property to the Murphy Wetland, east-northeast from the
northern portion of the Whitney Building/former drum washing area beyond the
Aberjona Property line, and east-northeast from the vicinity of the former UST (AB-201
area) at the Abeijona Property toward the Aberjona River. The plume footprint within the
intermediate/deep overburden is generally similar to that of the shallow overburden
plume, while the lateral plume dimensions within the shallow bedrock are somewhat
reduced relative to the overburden plumes. Shallow bedrock impacts are also present in
the vicinity of the MW-4 well cluster at the Whitney Property.

• NAPL - NAPL has been observed in several wells on the Murphy Property (Figure E-2). As
part of the Supplemental RI, wells MW-7, MW-16 and MW-24 were gauged for water level
and thickness of NAPL. NAPL samples were collected from wells MW-16, MW-24 and
MW-25 for analysis of VOCs, VPH/EPH, TPH, PCB congeners, petroleum fingerprinting,
density and viscosity. Subsequently, NAPL samples were collected from MW-16, MW-24,
MW-25 (PCBs only) for chemical analysis, and found to contain 1,2-cis-DCE up to
1,500,000 |ig/kg, PCBs up to 282,000 ng/g, Naphthalene up to 1,200,000 |ig/kg, and C11-C22
aromatic hydrocarbons up to 84,200 |ig/kg. Corresponding groundwater samples suggest that
C11-C22 aromatic hydrocarbons, VOCs, and PCBs are migrating from the NAPL to
groundwater and wetland sediments/soils.

At the Whitney Property, NAPL observations have been limited to well WB-201S in October
2011 and July 2013. NAPL was not observed at any other wells on the Whitney Property
during the Supplemental RI investigation activities.

• Soil Vapor - Soil vapor from the office portion of the Murphy building had a mix of VOCs
detected, including chlorinated VOCs, petroleum hydrocarbon fractions, and CFC-113.
Detections in soil vapor below the building are consistent with known historic or current
activities in this area, including the former oil pit that is located beneath this building or the
ongoing management of waste oils. The detections of VOCs in soil vapor at the Whitney
Property were expected given the distribution of VOCs in shallow groundwater and soils
around the building. Overall, the soil vapor data combined with the soil and groundwater data

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indicate that the former drum washing operations area and floor drain line are a primary
source area at the Whitney Property. A mix of VOCs were detected at the main building at
the Abeijona Property. The detections are consistent with the documented historical use of
the property as an auto junk and salvage yard.

At the house located on the Aberjona Property, two rounds of vapor intrusion sampling were
performed in 2013. Concentrations of 1,1-dichloroethane, benzene, naphthalene, chloroform,
and TCE were detected. Although the vapor intrusion pathway for chloroform and TCE
(present in shallow groundwater, sub-slab soil gas and indoor air) was complete, the BRA
concluded that, while TCE and chloroform were identified as indoor air contaminants of
potential concern, the calculated risk levels were below EPA's risk management criteria for
carcinogens and/or non-carcinogens and vapor intrusion at the Aberjona Residence does not
pose a significant risk. No further action is recommended for this building.

5. Primary Sources and Routes of Migration

The release mechanisms resulting in contamination include known, documented, and suspected
releases of petroleum or hazardous materials at the SWP. Based on the information concerning
sources of contamination and migration pathways, the following general media are affected by
releases from the SWP:

•	Soil associated with the former "oil yard" and "oil pit" at the Murphy Property, the former
drum washing area and drain line at the Whitney Property, and in the vicinity of the former
UST at the Aberjona Property;

•	Wetland sediments/soils within the Murphy Wetland;

•	Surface water within the Murphy Wetland;

•	Overburden and shallow bedrock groundwater beneath the SWP; and

•	NAPL within the Murphy Property (MW-7 and MW-16 areas) and Whitney Property (WB-
201 area).

The Abeijona River is a receiving medium for overburden groundwater. However, Site-related
contamination has not accumulated in the river as described in the Abeijona River Study which
was designed to investigate the nature and extent of contamination in the Abeijona River
sediments and surface water as well as evaluate potential human and ecological risks. EPA
merged the Wells G&H Aberjona River Study with the Industri-plex Operable Unit 2 (OU2)
Multiple Source Groundwater Response Plan (MSGRP) RI/FS. On January 31, 2006, EPA
released the Industri-plex OU2 (including Wells G&H OU-3) ROD.

The details of the fate and transport of constituents present in contaminated media (soil, wetland
sediment/soil, surface water, groundwater, NAPL and soil vapor) for the main constituents

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detected at the SWP are as follows:

Sources

Murphy Property - The COCs identified in media at the Murphy Property are primarily VOCs,
petroleum hydrocarbons, SVOCs, PCBs, and metals. The following primary sources of
contamination have been identified at this property:

•	Oil yard waste oil and solvent-contaminated oil ASTs;

•	Disposal of waste oils and solvent-contaminated oil in the oil pit;

•	Historic spills of fuel oil and reclaimed oil; and

•	Direct application of waste oils onto dirt roads to suppress dust.

Whitney Property - The COCs identified in media at the Whitney Property are primarily VOCs,
petroleum hydrocarbons, SVOCs, PCBs, pesticides, and metals. The following primary sources
of contamination have been identified at this property:

•	Discharge of drum waste and cleaning fluids into a floor drain (connected to the
MDC/MWRA sewer);

•	Direct releases (VOCs and oil/grease) to an MDC sewer manhole;

•	Historic activities and storage practices leading to direct release of drum waste onto the
ground; and

•	Various building fires releasing petroleum or other hazardous substances.

Aberjona Property - The COCs in media at the Abeijona Property are primarily VOCs,
petroleum hydrocarbons, SVOCs, and metals. The following primary sources of contamination
have been identified at this property:

•	Historical storage and burning of junk cars;

•	Gasoline and waste soil USTs;

•	Degreasing operations and releases of VOCs to an oil/water separator via a floor drain before
discharge to the sanitary sewer; and

•	Incidental releases (e.g., fluids from junk autos and dismantled auto parts).

Murphy Wetland - While this wetland was not used for commercial operations, it received

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contamination from sources on adjacent properties including:

• NAPL from the Murphy Property oil yard and oil pit;

• Sanitary sewer overflows;

• Periodic flooding of the adjacent Murphy and Whitney Properties, which likely released
contamination to the wetland;

• Overland runoff from rainfall events which transported contamination associated with
surficial soils and spills to the wetland;

• Drainage in a swale directly from the J.J. Riley Tannery property that caused sediment
deposition in the northern portion of the wetland by the railroad culvert; and

• Breaks in the MDC sewer line leading from the Whitney Property building.

The COCs in wetland sediment/soil at the Murphy Wetland are PCBs, petroleum hydrocarbons,
and metals. Metals have been detected in wetland surface water.

Routes of Migration

Most of the COCs identified are organic contaminants (VOCs, SVOCs, PCBs, and pesticides).
Inorganic COCs are metals: arsenic, chromium, cobalt, iron, lead, manganese, thallium, and zinc.
There are several pathways for contaminants to migrate from the point of origin at the SWP to
other locations and potential receptors including:

• Air migration;

• Surface water migration;

• Wetland sediment/soil migration;

• Soil migration; and

• Groundwater migration.

Air Migration - The migration of contaminants to air is a result of entrainment of soil particles by
the wind and by volatilization. The results of the soil vapor data collection and analysis best
characterize the soil vapor pathway at the SWP. The analysis indicated primarily VOCs in the
soil vapor data at each property. In general, the results were well correlated with historical
activities at each property. In addition to migration from soil/groundwater to outdoor air, the soil
vapor intrusion migration pathway is specific to migration of contaminants from soil under
buildings into indoor air. Testing at the residence on the Abeijona Property showed that the

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vapor intrusion pathway for chloroform and TCE (present in shallow groundwater, sub-slab soil
gas and indoor air) was complete.

Surface Water - Migration and redistribution of contaminants to local surface water can result
from flooding or migration of surface water from upstream tributaries. Other mechanisms
include groundwater discharge to surface water and surface runoff. The observations of impacts
to surface water are limited to sheen on the surface water in the Murphy Wetland, which is
correlated to the NAPL observed at several wells on the Murphy Property. Lead in groundwater
influenced by upward hydraulic gradients, may result in migration from groundwater to surface
water (and to wetland sediments). The presence of NAPL and lead at the Murphy Property is
consistent with the current and historic practices of waste oil management (former "oil pit" and
former "oil yard").

Wetland Sediments/Soils - Contaminants in wetland sediments/soils may be affected by periods
of high river flow or storm events. Sediments mobilized by high-energy storm waters and runoff
will be carried and ultimately deposited in a lower energy setting. Subsurface infrastructure
(culverts, drains) may also be a pathway to contaminant migration to sediments. Soil transport
from Murphy and Whitney Properties are believed to be primary sources of impacts to Murphy
Wetland sediments. NAPL, particularly at the Murphy Property, is also impacting sediments.
Sediments may also be impacted by upwelling of shallow groundwater. Off-site sources may
also have contributed to sediment impacts, primarily chromium. For example, storm water
originating from the former John J. Riley Tannery property west of the railroad tracks to the
Murphy Wetland (via the drainage ditch/swale and culvert) may have transported eroded
chromium impacted soils into the northern portion of the Murphy Wetland.

Soils - Impacted soils are generally believed to result primarily from discharge or disposal
directly to the soils. At the Murphy Property, the historic footprints of the former "oil pit" and
waste oil AST tank farm (former "oil yard") are well correlated to soil impacts at that property.
The historic drums washing area and the floor drain discharge line at the Whitney Property are
also very well correlated to the location of the soil impacts at that property. Soil concentrations
were not high or widespread at the Aberjona Property, except for petroleum hydrocarbon fraction
impacts in the area of the former 500-gallon diesel UST at the northeast corner of the main
building, near the former floor drains and waste oil tank on the east side of the building, and the
area immediately to the north of the main building.

At the SWP, contaminant migration from soil to groundwater may occur when there is a source
of soil impacts and recharge (rainfall) to prompt the migration. The soil-to-groundwater leaching
pathway is evident at the SWP based on the distribution of soil impacts and the observations of
dissolved phase contaminants in corresponding groundwater samples. The NAPL observed at the
Murphy and Whitney Properties also contribute to contaminant impacts in groundwater.

Groundwater - Groundwater generally becomes impacted because of direct discharge to
groundwater, because of leaching from soil to the groundwater, or because of migration within

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the groundwater system. At the SWP, the mechanism by which contaminants enter the
groundwater system is transport through the vadose zone and leaching from the soils (for volatile
contaminants and petroleum hydrocarbon fractions). This is evidenced by detections of the
highest concentrations of groundwater in the same areas as the highest concentrations in soils.
Like soils, the overarching patterns of detections in groundwater include distinct patterns of
metals, VOCs, SVOCs, pesticides, and PCBs that correlate well with documented historical
operations and releases at each of the properties including the former oil AST area ("oil yard")
and former waste "oil pit" at the Murphy Property, former drum washing operations area and
former drain line at the Whitney Property and the main operations area and central portion of the
Aberjona Property. Potential off-site sources of impacts to groundwater also exist, including
impacts associated with the Wildwood Source Area Property.

Groundwater flow is generally from southwest to northeast with components of flow in the
shallow overburden toward surface water bodies and wetlands. In the intermediate overburden
and shallow bedrock, flow is also from southwest to northeast, roughly parallel to the Wildwood
Source Area Property's southern property lines, with an eastward component of flow north of the
SWP. Seasonal river changes and periodic flooding may result in short-term local scale changes
to groundwater flow directions and gradients such that groundwater may be temporarily
influenced by two or more sources and result in a mixing zone.

Historically, shallow groundwater gradients and directions along the boundary between SWP and
the Wildwood Source Area Property have been variable because of groundwater extraction in the
valley (e.g., Riley Well 2, Wells G and H). The pumping and subsequent ceasing of pumping
impacted the migration from various local source areas (Murphy, Whitney, and Aberjona
Properties and Wildwood Source Area Properties) toward Riley Well 2 and resulted in areas of
groundwater mixing. After pumping at Riley Well 2 stopped (1989), ambient hydraulic gradients
were re-established.

Estimated Volumes of Impacted Media/Waste

The estimated volumes of impacted soils, groundwater, wetland sediments/soils and NAPL are
presented in the table below.

Approximate Impacted Media/Waste

Estimated Volumes

Impacted Soils

46,000 cubic yards

Impacted Groundwater

300,000 cubic yards

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Impacted Wetland Sediments/Soils

7,000 cubic yards

Impacted NAPL

6,000 cubic yards

6. Routes of Exposure

Human Health

The potentially complete human health exposure pathways include:

•	direct contact (incidental ingestion and/or dermal contact) with soil, surface water and
wetland sediment/soil4;

•	inhalation of fugitive dust released from soil;

•	potable use of groundwater (ingestion, dermal contact, and inhalation of vapors released
from groundwater used as household tap water); and

•	inhalation of potentially impacted indoor air following vapor intrusion.

Presently, the SWP is a mix of commercial buildings, an ice skating rink, and the Existing
Abeijona Residence. A wetland area (the Murphy Wetland) is present between the Murphy and
Whitney Properties. Potential exposures at the three commercial properties under current land
use conditions were characterized using a current commercial worker scenario. This scenario
assumed that adult workers will be exposed to contamination in exposed surface soil within the
industrial portions of the Murphy, Whitney and Aberjona Properties under current land use
conditions. This scenario also assumes that workers will be exposed to contaminants that have
potentially migrated to indoor air via the vapor intrusion pathway, evaluated through a screening-
level assessment of the soil vapor data.

Current older child trespasser exposures were evaluated assuming contact with exposed surface
soil at the Whitney Property and with sediment and surface water within the Murphy Wetland.
Current trespasser exposures at the Murphy and Aberjona Properties were not evaluated because
these properties are secured with gates and fencing, or covered with asphalt or concrete. Current
recreational and commercial exposures at the ice skating rink were not evaluated because the
area around the rink is paved and a vapor barrier was placed during building construction to

4 Both wetland sediment and wetland soil samples were collected from the Murphy Wetland area. The baseline human
health risk assessment combined the wetland sediment and wetland soil data together, and evaluated both media
combined as sediment.

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mitigate the vapor intrusion pathway.

As previously mentioned, there is a residence (the Existing Abeijona Residence) present in the
southeast portion of the Abeijona property. Residential exposures to soil at the Existing Abeijona
Residence were not evaluated because industrial activities did not occur on this portion of the
Aberjona Property. The existing house has historically been separated from the industrial
portion of the Abeijona Property by fencing, asphalt pavement and a concrete wall. Based on
SWP history, no industrial operations (e.g., stockpiling of scrap, storage of materials, automotive
repair-related activities) are known to have been performed at the Abeijona residential area (see
Appendix C of the FS for complete discussion). However, due to the presence of VOC-
contaminated shallow groundwater beneath the Existing Abeijona Residence, risks to current
young child and residents were characterized for the vapor intrusion pathway.

The future use of the SWP has not been determined. Therefore, exposures were evaluated for a
range of possible future land uses, including trespasser, recreational and commercial. The future
older child trespasser scenario assumed continued commercial use of the properties with the
removal of access obstacles and exposure barriers that are currently in place, resulting in
increased access to the properties and the wetland. Future older child trespasser exposures were
evaluated assuming contact with surface soil at the Murphy, Whitney and Aberjona Properties
and with sediment and surface water within the Murphy Wetland. The recreational use scenario
evaluated young children and adults who were assumed to be exposed to soil within the three
properties, as well as to surface water and sediment within the Murphy Wetland. Recreational
users have a higher intensity and frequency of exposure than that assumed for trespassers.

Future commercial uses of the SWP considered soil exposures to full-time workers, as well as
construction workers engaging in improvements or redevelopment of the properties. Exposures
to construction workers were also characterized for direct contact with shallow groundwater
exposed during excavation activities. Due to the predominant commercial/industrial nature of
the surrounding area and the mapped 500-year floodplain over portions of each of the properties,
future residential development of the Aberjona, Whitney, and Murphy Properties (exclusive of
the Existing Aberjona Residence) is considered highly unlikely and was not evaluated in the
baseline HHRA. However, Appendix C of the 2016 FS (as updated in Attachment 2 of the 2017
FS Report Addendum - Technical Memorandum) contains a screening-level risk evaluation for
future residential use of the properties to document the need for Institutional Controls for future
residential use due to residential risks for soil above EPA risk management criteria (Incremental
Lifetime Cancer Risk [ILCR] greater than 10"4 or a Hazard Index [HI]>1) for each of the
properties. In addition, the soil cleanup standards will not be protective of future daycare child
and school-age child who would be exposed more frequently than a recreational child, and
Institutional Controls will be necessary to restrict future daycare and school use. Future use of
SWP-wide groundwater as tap water was evaluated for nearby young child and adult residents,
assuming ingestion, dermal contact, and inhalation exposures during household water usage.

Ecological

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The potentially complete ecological exposure pathways are:

•	Uptake of contaminants from sediment, surface water, and wetland soil through roots
(vegetation);

•	Ingestion of contaminants bound to wetland soil (terrestrial invertebrates, birds,
mammals);

•	Ingestion of contaminants bound to sediment (benthic invertebrates, semi-aquatic wetland
birds and mammals)

•	Ingestion of dissolved and particulate contaminants in surface water (aquatic
invertebrates, semi-aquatic wetland birds and mammals);

•	Ingestion of contaminants through consumption of contaminated plants (herbivores,
omnivores); and

•	Ingestion of contaminants through consumption of contaminated invertebrate prey
(invertivores, omnivores).

Although inhalation and dermal absorption pathways are possibly complete for some receptors,
these pathways are considered to be minor compared to dietary ingestion and were not evaluated.

The exposure pathways are considered incomplete for media located below pavement, buildings
or other impervious surfaces that are considered inaccessible to ecological receptors and to non-
vegetated portions of the SWP. In addition, since groundwater does not directly discharge to the
ground surface (e.g., through seeps), there are no direct exposures to groundwater by
environmental receptors.

7. Principal Threat Waste

Principal threat wastes are those source materials considered to be highly toxic or highly mobile
which generally cannot be contained in a reliable manner or would present a significant risk to
human health or the environment should exposure occur. The manner in which principal threats
are addressed generally will determine whether the statutory preference for treatment as a
principal element is satisfied. Wastes generally considered to be principal threats are liquid,
mobile, and/or highly-toxic source material.

NAPL (Murphy and Whitney Properties) and significantly contaminated soils (i.e., 10 times
greater than the cleanup level and/or greater than or equal to PCBs at 50 mg/kg) within the
Northern Whitney Soil Area (Whitney Property) are Principal Threat Wastes.

The Principal Threat Wastes at the Northern Whitney Soil Area contain the highest
concentrations of PCBs (10 to 100 times higher than rest of the SWP) as well as other

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constituents such as chlorinated VOCs detected at the SWP, NAPL has been observed within this
portion of the Whitney Property (well WB-201S), and the cancer risk associated with EPCs
calculated using the 95% UCL for subsurface soil at the Whitney Property exceeds a 10"3 risk. It
is important that the soil in the Northern Whitney Soil Area be effectively remediated because of
the high concentrations of COCs, the presence of NAPL and surface suspended globules
containing floating hydrocarbons, PCBs and VOCs. The Northern Whitney Soil Area is a
significant source to groundwater contamination, as well as potentially other media, that must be
removed or otherwise aggressively treated to destroy or immobilize COCs. Excavation of the
Northern Whitney Soil Area would extend below the water table and have beneficial impacts on
groundwater, including removal of source material (including NAPL) and providing the
opportunity to blend the remaining contaminated soil below the water table with an amendment
prior to backfilling to provide soil and localized groundwater treatment.

NAPL is a source contributor of contaminants to soil and groundwater and is present on the
Murphy and Whitney Properties. NAPL associated with the former drum washing operations
area at the Whitney Property is characterized by well WB-201S as noted above in association
with the Northern Whitney Soil Area. The presence of NAPL associated with the former waste
oil AST area ("oil yard") and the former waste "oil pit" area at the Murphy Property,
characterized by the measurement of NAPL in wells MW-16, MW-18, MW-24, MR 206, and
MW-7, is also considered a Principal Threat Waste. NAPL is also potentially present in portions
of the Murphy Property including the former "oil pit" and the former waste oil ASTs ("oil yard")
area. The NAPL has been identified based on forensic testing as primarily lubricating oil.
Chemical analysis indicates that NAPL at the Murphy Property contains high levels of COCs
including VOCs (e.g., cis-l,2-DCE as high as 1,500,000 |ig/kg), PCBs (up to 282,000 nanograms
per gram [ng/g]), and petroleum compounds (e.g., naphthalene up to 1,200,000 |ig/kg, and Cn-
C22 aromatic hydrocarbons up to 84,200 |ig/kg). Corresponding groundwater samples indicate
that VOCs, PCBs and C11-C22 aromatic hydrocarbons are migrating from the NAPL to
groundwater and wetland sediments. Excavation of NAPL at both the Murphy Property and the
Northern Whitney Soil Area (Whitney Property) would remove and/or contain NAPL and
surface suspended globules, to the extent practicable, and prevent NAPL migration, leaching to
groundwater and discharge to wetlands.

Low-level threat wastes are those source materials that generally can be reliably contained and
that would present only a low risk in the event of exposure. Wastes that are generally considered
to be low-level threat wastes include non-mobile contaminated source material of low to
moderate toxicity, surface soil containing chemicals of concern that are relatively immobile in air
or groundwater, low leachability contaminants or low toxicity source material. The soils and
wetland sediments/soils on the SWP are considered Low-level Threat Wastes as they generally
can be contained (e.g., capped) and present relatively low risk in the event of exposure.

F. CURRENT AND POTENTIAL FUTURE SITE AND RESOURCE USES

The SWP, as well as the surrounding area, are commercially active and zoned industrial. Each

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property has at least one building in active use, and the properties are fenced and/or paved or
covered with gravel. Trespassers may access the Murphy Wetland, but the wetland area is not
currently a valuable recreational resource.

Currently, an automotive storage area and a fence-enclosed-locked dog exercise facility is
located in the northern portion of the Aberjona Property. In addition, a landscaping business and
a private athletic training facility utilize one of the buildings on the property. In 2008, an indoor
ice skating arena was constructed on the western portion of the property. The Existing Abeijona
Residence is also present in the southeast portion of the property.

Since barrel refinishing operations ceased, the Whitney Property has been used for a variety of
commercial purposes including indoor and outdoor equipment storage, truck parking, a wood
working shop, auto repairs, and equipment repairs. Currently the property is used by a number of
businesses, including construction, landscaping, tree removal, and automotive repair.

The Murphy Property is currently leased by Clean Harbors and is an active transfer, storage and
disposal facility for waste oil and solvent-contaminated oil. The facility is registered under
RCRA as a Treatment, Storage and Disposal Facility (TSDF). The main facility was constructed
in 1989 and 1990 and includes the waste oil facility with eleven ASTs, an office, a laboratory,
and restrooms. The AST area is underlain by a concrete dike containment area and is covered by
a canopy. A garage, located in the southern portion of the property, is used primarily for truck
maintenance. Operations at the property include collection and gravity separation of waste oils
and segregation of solids, liquids, and oils for subsequent disposal or resale. Access to the
operating portion of the property is limited by fencing.

Commercial/industrial land use is assumed to continue in the future, except for continued use of
the Existing Aberjona Residence for residential use and the ice skating rink for recreational use.
A potential redevelopment option for the SWP includes expanded use of the properties for
recreational activities with the construction of additional recreational facilities and increased
access to the Murphy Wetland. Due to the predominant commercial/industrial nature of the
surrounding area and the mapped 500-year floodplain over portions of each of the properties,
future residential development of the Abeijona, Whitney, and Murphy Properties is considered
highly unlikely and was not evaluated in the baseline HHRA. Therefore, EPA's cleanup levels
for soil are based on a future recreational land use scenario, the highest anticipated use of the
properties.

There is currently no potable or non-ingestion use of groundwater at the SWP since the facilities
and the surrounding areas are connected to the municipal water supply. In 2004, MassDEP
prepared a Groundwater Use and Value Determination for the Wells G&H Superfund Site. The
purpose of the Use and Value Determination is to identify whether the aquifer at the Site should
be considered of "High," "Medium," or "Low" use and value. In the development of its
Determination, MassDEP applied the criteria for groundwater classification as promulgated in
the MCP. The classification contained in the MCP considers criteria similar to those

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recommended in the Use and Value Guidance. MassDEP concluded a "Medium" groundwater
use and value determination was appropriate for the Wells G&H aquifer because of its
significant current and future ecological value to the Aberjona River and associated wetlands and
its potential value as a drinking water supply in the future. Based upon this determination, future
potable use of SWP-wide groundwater by a resident is possible. Therefore, EPA is proposing
cleanup levels based on federal and state drinking water standards, including MCLs, and risk-
based criteria that support this use as a future potential drinking water source.

G. SUMMARY OF SITE RISKS

A BRA was performed to estimate the probability and magnitude of potential adverse human
health and environmental effects from exposure to contaminants associated with the SWP
assuming no remedial actions were to be taken. It provides the basis for taking remedial action
when action is warranted, and identifies the contaminants and exposure pathways that need to be
addressed by the remedy. The human health risk assessment (HHRA) followed a four step
process: 1) hazard identification, which identified those hazardous substances which, given the
specifics of the SWP, were of significant concern; 2) exposure assessment, which identified
actual or potential exposure pathways, characterized the potentially exposed populations, and
determined the extent of possible exposure; 3) toxicity assessment, which considered the types
and magnitude of adverse health effects associated with exposure to hazardous substances, and
4) risk characterization and uncertainty analysis, which integrated the three earlier steps to
summarize the potential and actual risks posed by hazardous substances at the SWP, including
carcinogenic and non-carcinogenic risks and a discussion of the uncertainty in the risk estimates.
A summary of the components of the human health and ecological risk assessments which
support the need for remedial action is provided below. The complete baseline human health
risk assessment and ecological risk assessment can be found in the March 2014 Baseline Human
Health and Ecological Risk Assessment (EPA, 2014). Updates to the 2014 BRA, based on
changes to toxicity values since the 2014 BRA was completed, are presented in Appendix C of
the 2016 FS and in Attachment 2 of the 2017 FS Report Addendum - Technical Memorandum.

1. Human Health Risk Assessment

A baseline HHRA, conducted pursuant to EPA Risk Assessment Guidance for Superfund
(RAGS), was completed for the SWP to evaluate the likelihood and magnitude of potential
human health effects associated with the current land use of the SWP, as well as possible future
land uses of the SWP, which included recreational and commercial. The HHRA evaluated
baseline risks which assume that current and future land uses occur in the absence of any
remedial actions (EPA, 2014).5 As previously discussed, residential land use was not evaluated
in the BRA. However, Appendix C of the 2016 FS (as updated in Attachment 2 of the 2017 FS
Report Addendum - Technical Memorandum) contains a screening-level risk evaluation for

5 EPA, 2014. Baseline Human Health and Ecological Risk Assessment, Southwest Properties, Wells G&H Superfund
Site, Operable Unit 2, Woburn, Massachusetts. March 2014.

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future residential use of the properties to document the need for Institutional Controls to restrict
future residential, school, and daycare use for each of the properties, as discussed below.

Section 1: Hazard Identification

Seventy-eight of the approximately 120 chemicals detected at the SWP were selected for
evaluation in the HHRA as chemicals of potential concern (COPCs). The COPCs were selected
to represent potential SWP-related hazards based on toxicity, concentration, frequency of
detection, and mobility and persistence in the environment and can be found in Tables 3-2.1
through 3-2.6 in Section 3 of the baseline HHRA (EPA, 2014). From this, a subset of the
chemicals was identified in the HHRA and updated in Appendix C of the December 2016 FS and
Attachment 2 of the 2017 FS Report Addendum - Technical Memorandum as presenting a
significant current or future risk and/or were identified at the SWP in excess of the appropriate
chemical-specific applicable or relevant and appropriate requirements (ARAR)6 value and are
referred to as the COCs in this ROD. The COCs are summarized in Tables G-l through G-4.
These tables contain the exposure point concentrations used to evaluate the reasonable maximum
exposure (RME) scenario in the baseline HHRA for the COCs. Estimates of average or central
tendency exposure concentrations for the COCs and all COPCs can be found in Tables 3-3.1
through 3-3.9 in Section 3 of the baseline HHRA (EPA, 2014). All of the COCs in these tables
were identified as presenting a significant future risk in the baseline HHRA except for 1,1-
dichloroethene, 1,1,1-trichloroethane, and 4,4'-DDE in groundwater. Of these, 1,1-
dichloroethene and 1,1,1-trichloroethane are included because their maximum detected
concentrations in groundwater exceed a chemical specific-ARAR value (i.e., the MCL). 4,4'-
DDE was not included as a groundwater COPC in the baseline HHRA, but it would now be
included due to its recent classification as a volatile chemical. 4,4'-DDE is also now included as
a groundwater COC because its maximum detected concentration is associated with a risk in
excess of 10"6, the trigger for inclusion as a COC if the total risk is greater than EPA risk
management criteria. In addition, benzo(a)pyrene and other carcinogenic PAHs
(benzo(a)anthracene, benzo(b)fluoranthene, dibenz(a,h)anthracene, and indeno(l,2,3-cd)pyrene)
in soil and groundwater were identified as COCs in the baseline HHRA, but are no longer
included as COCs (except for benzo(a)pyrene in groundwater which is retained as a COC) due to
the publication of revised toxicity values in 2017. Appendix C of the 2016 FS and Attachment 2
of the 2017 FS Report Addendum - Technical Memorandum provide discussions of changes to
COPCs and COCs since the baseline HHRA was completed.

Section 2: Exposure Assessment
Exposure to chemicals of concern were estimated quantitatively or qualitatively through the

6 ARARs are all standards, requirements, criteria or limitations under any Federal environmental law and all standards,
requirements, criteria or limitations under any more stringent State environmental or facility siting law, unless a waiver
is invoked, that are applicable or relevant and appropriate to implementing a CERCLA remedy.

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development of several hypothetical exposure scenarios. Exposure scenarios were developed
considering the nature and extent of contamination, the location of the SWP, current and future
potential use of the SWP, and identification of potential receptors and exposure pathways.

Current and potential future SWP-specific pathways of exposure to COCs were determined. The
extent, frequency, and duration of current or future potential exposures were estimated for each
pathway. From these exposure parameters, a daily intake level for each SWP-related chemical
was estimated.

Presently, the SWP are comprised of three contiguous properties of land known as the Aberjona
Property, Whitney Property, and Murphy Property. The SWP are located in a heavily developed
commercial and industrial area and are surrounded by similar industrial/commercial properties to
the north, east, west, and south. The three properties themselves are zoned industrial. A residence
(the Existing Aberjona Residence) is located on the Aberjona Property. A wetland area (referred
to as the Murphy Wetland) extends along the northern border of the SWP between the Murphy
and Whitney Properties. Exposures were evaluated for a range of possible future land uses,
including recreational and commercial/industrial. The recreational use scenario evaluated young
children and adults who were assumed to be exposed to soil, as well as to wetland surface water
and sediment, if wading activities occur. The exposure evaluation associated with commercial
and industrial uses of the SWP considered full-time adult workers exposed to soil. Evaluation of
exposure was also performed for future construction workers exposed to SWP soils and shallow
groundwater. Though the evaluation for soil exposure assuming future residential use of the
SWP was not evaluated in the baseline HHRA, exposure to COPCs in SWP-wide groundwater
used as a potable water source was evaluated in the baseline HHRA. Additional details on
current and potential future land use can be found in Section 3.1.2 of the baseline HHRA (EPA,
2014).

The following is a brief summary of the exposure pathways that were found to present a
significant risk (Incremental Lifetime Cancer Risk [ILCR] greater than 10"4 or a Hazard Index
[HI] > 1) at the SWP assuming a reasonable maximum exposure scenario. A more thorough
description of all exposure pathways evaluated in the risk assessment including estimates for an
average exposure scenario, can be found in Section 3.3.1 and on Tables 3-4.1 through 3-4.10 in
Section 3 of the baseline HHRA (EPA, 2014).

No current exposure pathways were found to present a significant risk at the SWP.

The following future exposure pathways were found to present a significant risk at the SWP:
• Trespasser (older child) with exposure to Murphy Wetland sediment (by ingestion and

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dermal contact);7

• Recreational user (adult and young child) with exposure to surface and/or subsurface soil

(by ingestion and dermal contact) at the Whitney Property and Murphy Property;8

• Recreational user (adult and young child) with exposure to Murphy Wetland sediment (by

ingestion and dermal contact);9

• Construction worker with exposure to subsurface soil (by ingestion, inhalation of

particulates, and dermal contact) and/or shallow groundwater (by ingestion and dermal
contact) at the Whitney Property and Murphy Property;10

• Resident (adult and young child) with exposure to SWP-wide groundwater (by ingestion,

inhalation, and dermal contact) used as tap water.11

In addition, the vapor intrusion pathway is considered to be potentially complete under future
land use conditions if occupied buildings are constructed within 100 feet of overburden soil
where VOCs have been detected (at any concentration), and within 100 feet of overburden
groundwater in which VOCs have been detected at concentrations greater than vapor intrusion
screening levels (VISLs).

The baseline HHRA did not include an evaluation of future residential use of the SWP.

However, a screening-level risk evaluation for residential soil exposures at the SWP has been

7 For future older child trespasser (12-18 years of age) sediment exposures, an exposure frequency of 52 days/year was used, along
with an exposure duration of 6 years. An ingestion rate of 100 mg/day was used. Dermal contact was assumed with 4,500 cm2 of
surface area and an adherence factor of 0.2 mg/cm2-event. A body weight of 57 kg was used, along with a fraction ingested term
of 0.5 which assumes half of the daily sediment ingestion exposure occurs at the SWP.

8 For future recreational user soil exposures, exposure durations of 24 years and 6 years, respectively, were presumed for an adult
and young child. Body weights of 70 kg and 15 kg were used for the adult and young child, respectively. Dermal contact was
assumed with 5,700 cm2 of surface area for the adult and 2,800 cm2 for the young child, with adherence factors of 0.07 and 0.2
mg/cm2-event for the adult and child, respectively. An exposure frequency of 78 days/year was used.

9 For future recreational user sediment exposures, an exposure frequency of 78 days/year was used, along with exposure durations
of 24 years and 6 years, respectively, for an adult and young child. Ingestion rates of 100 mg/day and 200 mg/day were used for
the adult and child, respectively. Body weights of 70 kg and 15 kg were used for the adult and young child, respectively. Dermal
contact was assumed with 5,700 cm2 of surface area for the adult and 2,800 cm2 for the young child, with adherence factors of 0.07
and 0.2 mg/cm2-event for the adult and child, respectively. A fraction ingested term of 0.5 was used which assumes half of the
daily sediment ingestion exposure occurs at the SWP.

10 For future construction worker soil and groundwater exposures, an exposure frequency of 125 days/year was used, along with
an exposure duration of 1 year. A body weight of 70 kg was used. A soil ingestion rate of 330 mg/day was used. Dermal contact
with soil was assumed with 3,300 cm2 of surface area and an adherence factor of 0.3 mg/cm2-event. Fugitive dust exposures were
assumed to occur 8 hours/day for 125 days/year. Ingestion of groundwater was assumed at a rate of 0.05 liters/day. Dermal contact
with groundwater was assumed with 3,300 cm2 of surface area.

11 For future residential exposures to SWP-wide groundwater, drinking water ingestion rates of 2 L/day and 1 L/day for the adult
and young child, respectively, were assumed. An exposure frequency of 350 days/year was used for a combined exposure duration
of 30 years. Dermal contact was assumed with 18,000 cm2 of surface area for the adult, and 6,600 cm2 for the young child.
Showers/baths were assumed to occur 350 days/year for 0.58 hr/day for the adult and 1 hr/day for the young child. Inhalation during
showers/baths evaluated using the Andelman model with a volatilization factor of 0.5 L/m3.

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performed and is included in Appendix C of the 2016 FS (as updated in the 2017 FS Report
Addendum - Technical Memorandum) for surface and subsurface soil at the Whitney Property,
Murphy Property and the industrial portion of the Abeijona Property. This screening-level risk
evaluation estimated future residential risks to be significant, indicating the need for Institutional
Controls preventing future residential use of these industrial parcels. No risk evaluation was
performed for the Existing Abeijona Residence because no industrial operations are known to
have been performed on the residential portion of the property, the residential area is separated
from the industrial parcel by fencing, asphalt pavement, and a solid wall, and soil samples
collected from the residential portion of the property display similar concentrations to those
collected from locations known to be unimpacted by SWP operations. In addition, the soil
cleanup standards will not be protective of future daycare child and school-age child who would
be exposed more frequently than a recreational child, and Institutional Controls will be necessary
to restrict future daycare and school use.

Note that the baseline HHRA was completed in early 2014. After the completion of the baseline
HHRA, EPA finalized a Directive to update standard default exposure factors and frequently
asked questions associated with these updates (located online at

http://www.epa.gov/oswer/riskassessment/superfund_hh_exposure.htm; items # 22 and #23 of
this web link). Applying these updated standard default exposure factors to the risk assessment
would possibly result in a slight decrease of the risk estimates; however, it would not change the
previous conclusions regarding unacceptable risks at the SWP. These updated standard default
exposure factors have been utilized during development of risk-based cleanup levels (see Section
L of this ROD).

Section 3: Toxicity Assessment
Carcinogenic Effects

The potential for exposure to a chemical to result in a carcinogenic effect is generally described
by two factors: a statement reflecting the degree of confidence that the compound causes cancer
in humans and a potency estimate, indicating how potent the chemical may be at causing cancer,
with the general assumption that every exposure has some probability of resulting in cancer. The
descriptor reflecting the degree of confidence that the compound causes cancer in humans may
be either an alpha-numeric value or a narrative. Both are closely tied to the nature and extent of
information available from human and animal studies. The cancer potency estimate is a
quantitative measure of a compound's ability to cause cancer, and is generally expressed as
either a cancer potency factor or an inhalation unit risk value. Cancer potency estimates and unit
risk values are toxicity estimates developed by EPA based on epidemiological and/or animal
studies, and they reflect a conservative "upper bound" of the potency of the carcinogenic
compound. That is, the true potency is unlikely to be greater than the potency described by EPA.
Table G-5 presents these cancer toxicity values and cancer classifications for the COCs at the
SWP.

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In some cases, however, EPA may conclude that it is not appropriate to generate a cancer
potency estimate or unit risk value given the mode of action of the known or suspect carcinogen.
Currently, EPA's default procedure for characterizing cancer risk for compounds which may
exhibit a threshold for carcinogenic effects, mirrors the process used to describe the potential for
adverse non-cancer effects described in the section which follows. A summary of the cancer
toxicity data relevant to the COCs at the SWP is presented in Table G-5. EPA's Cancer
Guidelines and Supplemental Guidance (March 2005) have been used as the basis for analysis of
carcinogenicity risk assessment.

In January 2017, EPA revised toxicity values for benzo(a)pyrene. As discussed in Attachment 2
of the 2017 FS Report Addendum - Technical Memorandum, use of the revised toxicity values
for benzo(a)pyrene and in association with Relative Potency Factors for the other carcinogenic
PAHs, resulted in carcinogenic PAHs no longer being selected as COCs for soil or groundwater,
except for benzo(a)pyrene which was retained as a groundwater COC.

Non-Carcinogenic Effects and Non-Linear Carcinogenic Effects

For addressing non-carcinogenic effects and effects of carcinogenic compounds which exhibit a
threshold, it is EPA's policy to assume that a safe exposure level exists, which is described by
the reference dose (RfD) or reference concentration (RfC). RfDs and RfCs have been developed
by EPA as estimates of a daily exposure that is likely to be without an appreciable risk of an
adverse health effect when exposure occurs over the duration of a lifetime. RfDs and RfCs are
derived from epidemiological and/or animal studies and incorporate uncertainty factors to help
ensure that adverse health effects will not occur. The RfDs and RfCs relevant to the SWP are
presented in Table G-6.

The toxicity values presented in Tables G-5 and G-6 are those used in the baseline HHRA,
except for compounds where a toxicity update occurred since the baseline HHRA was
completed. The results presented in the following section (Risk Characterization) are based on
the current toxicity values as presented in Appendix C of the 2016 FS and Attachment 2 of the
2017 FS Report Addendum - Technical Memorandum. Appendix C of the 2016 FS and
Attachment 2 of the 2017 FS Report Addendum - Technical Memorandum provide a discussion
of the changes to toxicity values since the baseline HHRA was completed. The current toxicity
values have also been used during development of risk-based cleanup levels (see Section L of
this ROD).

Changes in toxicity values are associated with the RfC for trans-l,2-dichloroethene, and with the
RfD value for the C5-C8 aliphatic petroleum hydrocarbon fraction. In May 2014, EPA removed
the RfC for trans-1,2-dichloroethene from the PPRTV database. Based on this change, this
compound is no longer included as a COC for groundwater due to risk, but is retained as a COC
because its maximum detected concentration exceeds an ARAR. The baseline HHRA used the
hexane RfD provided in the Health Effects Assessment Summary Tables (HEAST) for
evaluating the non-cancer risk of the C5-C8 aliphatic fraction. This RfD has been superseded by

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the Integrated Risk Information System (IRIS) evaluation for hexane which no longer endorses
the use of this RfD value. Instead, the Provisional Peer-Reviewed Toxicity Value (PPRTV)
document "Provisional Peer-Reviewed Toxicity Values for Complex Mixtures of Aliphatic and
Aromatic Hydrocarbons" recommends use of the PPRTV subchronic RfD for hexane as a
chronic RfD for the C5-C8 aliphatic fraction. This RfD was used in the development of cleanup
levels for this fraction. In addition, in June 2015, EPA classified aldrin, benzo(a)anthracene,
chlordane, 4,4'-DDE, 1,4-dioxane, heptachlor, heptachlor epoxide, PCBs, and dioxin-like PCBs
as volatile (as defined in the Regional Screening Levels June 2015 update found at
http://www.epa.gov/reg3hwmd/risk/human/rb-concentration_table/index.htm). Because these
compounds with the exclusion of 4,4'-DDE, are already COCs for groundwater, these changes
do not impact the conclusions of the risk assessment presented below. Attachment 2 of the 2017
FS Report Addendum - Technical Memorandum identifies 4,4'-DDE as a groundwater COPC
and COC based on this change. Inhalation toxicity values for these compounds have now been
used for development of risk-based cleanup levels (see Section L of this ROD) and have,
therefore, been included in Tables G-5 and G-6.

Section 4: Risk Characterization

The risk characterization combines the exposure estimate with the toxicity information to
estimate the probability or potential that adverse health effects may occur if no action were to be
taken at a site. A separate characterization is generated depending on the nature of the adverse
effect. Cancer risks are generally expressed as a probability whereas the potential for adverse
non-cancer effects (and carcinogenic effects resulting from non-linear [i.e., exhibiting a threshold
of toxicity] mode of action [MO A] compounds) are described in terms what is thought to be a
safe exposure level.

For exposure to most known or potentially carcinogenic substances, EPA believes that as the
exposure increases, the cancer risk increases. In characterizing risk to these types of
carcinogenic compounds, a chemical- specific exposure level is generally multiplied with the
cancer potency factor or inhalation unit risk to estimate incremental lifetime cancer risk as a
result of exposure to site contaminants. To the extent that EPA has deemed that data are
sufficient to apply the provisions of the 2005 Children's Supplemental Cancer Risk Guidelines,
special consideration of the increased susceptibility to carcinogenic effects that children may
have, was included in the risk characterization. The 2005 Children's Supplemental Cancer
Guidelines were used to describe any such heightened susceptibility among potentially exposed
children. Typically, the resulting cancer risk estimates are expressed in scientific notation as a
probability (e.g., 1 x 10"6 or 1E-06 for 1/1,000,000) and indicate (using this example), that an
average individual is not likely to have greater that a one in a million chance of developing
cancer over 70 years as a result of site-related exposure (as defined) to the compound at the
stated concentration.

All risks estimated represent an incremental risk of cancer from exposures to contamination

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originating from the SWP. These are risks above and beyond that which we face from other
causes such as from cigarettes or ultra-violet radiation from the sun. The chance of an individual
developing cancer from all other (unrelated to the SWP) causes has been estimated to be as high
as one in three. EPA generally views site related cancer risks in excess of 10"4 as unacceptable.
Current EPA practice considers carcinogenic risks to be additive when assessing exposure to a
mixture of hazardous substances.

In assessing the potential for adverse non-carcinogenic effects (and carcinogenic effects resulting
from non-linear MOA compounds), a hazard quotient (HQ) is calculated by expressing the
exposure (or the exposure concentration in the case of air exposures) as a ratio of the reference
value (RfD or RfC). A HQ < 1 indicates that a receptor's exposure to a single contaminant is
less than the safe value and that adverse effects are unlikely. Conversely, a HQ > 1 indicates that
adverse effects as a result of exposure to the contaminant are possible. To account for additive
effects resulting from exposure to more than one compound, a Hazard Index (HI) is generated by
adding the HQs for all chemicals of concern that have the same or a similar mechanism or mode
of action. As a conservative measure and a common practice, HQs are often added for all
compounds of concern that affect the same organ or system (i.e., liver, nervous system) since the
mechanism or mode of action is not always known. A HI < 1 indicates that adverse effects are
unlikely whereas a HI > 1 indicates adverse effects are possible. Generally, EPA views HI
values based on site-related exposure in excess of unity as unacceptable. It should be noted that
the magnitude of the HQ or HI is not proportional to the likelihood that an adverse effect will be
observed.

As presented in Attachment 2 of the 2017 FS Report Addendum - Technical Memorandum, the
Integrated Exposure and Uptake Biokinetic (IEUBK) and Adult Lead modeling performed in the
baseline risk assessment were revised using updated model parameters recommended by EPA
and a target blood lead level of 5 ug/dl. The outcome of the modeling for the future recreational
scenario for surface and subsurface soil at the properties and wetland sediment/soil at the
Murphy Wetland continues to be consistent with the conclusions of the baseline risk assessment,
identifying only lead in wetland sediment/soil as a COC (see discussion below for Future
Recreational User - Wetland Sediment/Soil). Likewise, for current/future commercial use of the
properties, the revised modeling did not identify lead as a surface or subsurface soil COC,
consistent with the conclusions of the baseline risk assessment. Lead is a COC in groundwater,
as discussed below in the Future Resident - Groundwater Section.

The following is a summary of the media and exposure pathways that were found to present a
significant risk exceeding EPA's cancer risk range and non-cancer threshold at the SWP. Only
those exposure pathways deemed relevant to the remedy being proposed are presented in this
ROD. Readers are referred to Section 3-5.2 and Tables 3-7, 3-9 and 3-10 of the baseline HHRA
(EPA, 2014) for a more comprehensive risk summary of all exposure pathways evaluated for all
COPCs, and for estimates of central tendency risk.

Future Recreational User - Soil

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Tables G-7 and G-8 depict the carcinogenic and non-carcinogenic risk summaries for the COCs
in soil evaluated to reflect potential future recreational user ingestion and dermal exposure
corresponding to the RME scenario. For the future young child and adult recreational user,
carcinogenic and non-carcinogenic risks exceeded the EPA acceptable risk range of 10"4 to 10"6
and/or a target organ HI of 1 at the Whitney Property and Murphy Property in both surface and
subsurface soil. The exceedances are primarily due to chlorinated VOCs, PAHs, pesticides,
PCBs, arsenic, hexavalent chromium, and/or thallium in soil at:

•	Whitney Property (surface soil) - primarily due to PCBs;

•	Whitney Property (subsurface soil) - primarily due to vinyl chloride, TCE, bis(2-

ethylhexyl)phthalate, PCBs, pesticides, arsenic, and hexavalent chromium; and

•	Murphy Property (surface and subsurface soil) - primarily due to thallium.

Construction Worker - Soil and Shallow Groundwater

Table G-9 depicts the non-carcinogenic risk summary for the COCs in soil and groundwater
evaluated to reflect potential future construction worker ingestion, dermal, and inhalation
exposure corresponding to the RME scenario. For the future adult construction worker, non-
carcinogenic risks exceeded the EPA target organ HI of 1 at the Whitney Property and Murphy
Property in subsurface soil and/or shallow groundwater. The exceedances are primarily due to
PCBs in soil and chlorinated VOCs in shallow groundwater at:

•	Whitney Property (subsurface soil) - primarily due to PCBs;

•	Whitney Property (shallow groundwater) - primarily due to cis-l,2-DCE, PCE and TCE;

and

•	Murphy Property (shallow groundwater) - primarily due to cis-l,2-DCE.

Future Trespasser - Wetland Sediment/Soil

Table G-10 depicts the non-carcinogenic risk summary for the COCs in wetland sediment/soil
evaluated to reflect potential future trespasser ingestion and dermal exposure at the Murphy
Wetland corresponding to the RME scenario. For the future older child/adolescent trespasser,
non-carcinogenic risks exceeded the EPA target organ HI of 1. The exceedance is primarily due
to PCBs in wetland sediment/soil.

Future Recreational User - Wetland Sediment/Soil

Table G-ll depicts the non-carcinogenic risk summary for the COCs in wetland sediment/soil
evaluated to reflect potential future recreational user ingestion and dermal exposure at the

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Murphy Wetland corresponding to the RME scenario. For the future young child and adult
recreational user, non-carcinogenic risks exceeded the EPA target organ HI of 1. The
exceedance is primarily due to PCBs and CI 1-C22 aromatic petroleum compounds in wetland
sediment/soil.

The IEUBK Model was used to evaluate the potential hazards resulting from exposure to lead for
young children less than 7 years of age as the most sensitive receptor group. The average weekly
time-weighted wetland sediment/soil lead concentration was used as the wetland sediment/soil
concentration in the model, along with model assumptions presented in Attachment 2 of the 2017
FS Report Addendum - Technical Memorandum, including a target blood lead level of 5 ug/dl.
The outcome of the modeling identified lead is a COC in wetland sediment/soil at the Murphy
Wetland, consistent with the conclusions of the baseline HHRA.

Future Resident - Groundwater

Tables G-12 and G-13 depict the carcinogenic and non-carcinogenic risk summaries for the
COCs in groundwater evaluated to reflect potential future residential potable water exposure
corresponding to the RME scenario (under the assumption that groundwater associated with the
SWP is used as a source of potable water in the future). For the future resident using untreated
groundwater as household water, carcinogenic and non-carcinogenic risks exceeded the EPA
acceptable risk of 10"4 and/or a target organ HI of 1 for groundwater. The exceedances were due
primarily to the presence of VOCs, PAHs, PCBs, pesticides, petroleum hydrocarbon fractions,
arsenic, cobalt, iron, and manganese in SWP-wide groundwater. Though not listed on Tables G-
12 and G-13, lead was identified as a SWP-wide groundwater COC in the baseline HHRA
because lead concentrations in groundwater exceed ARARs. The VOCs trans-1,2-
dichloroethene, 1,1,1-trichloroethane and 1,1-dichloroethene are also SWP-wide groundwater
COCs because their maximum detected concentrations exceed ARARs, even though the baseline
HHRA did not identify them as primary risk contributors. In addition, the pesticide 4,4'-DDE is
now identified as a groundwater COC based on its recent identification as a volatile compound,
and carcinogenic PAHs, except for benzo(a)pyrene, are no longer identified as groundwater
COCs (see above discussion and Attachment 2 of the 2017 FS Report Addendum - Technical
Memorandum).

Section 5: Uncertainties

The baseline HHRA identified that elevated sample quantitation limits (SQLs) were reported for
some constituent analytical results, which may mask the presence of that constituent in the
affected samples. This may result in an underestimation of risk. One chemical for which this may
have occurred is 1,4-dioxane. All results for this chemical were non-detect in soil, therefore, it
was not quantitatively evaluated in the risk assessment. Soil SQLs for this chemical range from
0.041 mg/kg to 460 mg/kg, compared to a residential soil Regional Screening Level (RSL) of 5.3
mg/kg and a commercial soil RSL of 24 mg/kg. Therefore, excluding this chemical from the

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quantitative assessment could have resulted in an underestimation of the risk, if 1,4-dioxane was
present at concentrations greater than the RSL. However, all locations with elevated SQLs were
located on the Whitney Property where risks calculated for soils were above EPA risk
management criteria.

The baseline HHRA also identified that in groundwater, a number of 2011 non-detect results for
1,4-dioxane were rejected. The maximum detected concentration (78 (J,g/L) was used as the EPC
for the RME scenario, potentially resulting in an underestimation of risk if the presence of higher
concentrations of 1,4-dioxane in groundwater was masked by the rejected data. However, use of
the maximum detected concentration results in the conclusion that 1,4-dioxane is a risk
contributor in groundwater. Therefore, the conclusions of the risk assessment have not been
affected by the rejected groundwater data and elevated SQLs for 1,4-dioxane, though the
potential extent of 1,4-dioxane in groundwater cannot be accurately determined based on the
available data.

Carcinogenic and non-carcinogenic risks for each receptor were not summed across all media.
For example, the risks to the recreational and trespasser receptors from surface water and
wetland sediment/soil were not summed with those from soil ingestion and dermal contact for
the three properties. This may have resulted in an underestimation of cumulative risk for these
receptors. However, summing the risks for all pathways in this circumstance would not have a
significant impact on the overall calculated risks because the risk associated with exposure to
wetland sediment/soil is significantly greater than for exposure to soil. In addition, risks from a
given medium were not summed across exposure areas (e.g., soil media across Abeijona
Property, Whitney Property and Murphy Property). That is, for any given receptor, risks were
calculated assuming that exposure occurs at only one property. This assumption is uncertain
since a given recreational receptor may spend a portion of his/her time in one exposure area and
a portion in another. Risks to such an individual would be intermediate between the risks to
individuals exposed solely within each exposure area.

2. Ecological Risk Assessment

An Ecological Risk Assessment (ERA) was prepared for the SWP to evaluate the likelihood and
magnitude of potential ecological risks associated with the Murphy Wetland at the SWP (TRC,
2014). The technical guidance used to perform the ERA came primarily from "Ecological Risk
Assessment Guidance for Superfund: Process for Designing and Conducting Ecological Risk
Assessments EPA/540/R-97/006" (EPA, 1997).

The ERA evaluated data collected during the 1995, 1997, 2003 and 2004 field programs to
estimate the risk of ecological harm associated with SWP-related Chemicals of Potential
Ecological Concern (COPECs) in wetland surface soil as well as surface water and wetland
sediment associated with the SWP's seasonally ponded surface water body.

Section 1: Identification of Chemicals of Potential Ecological Concern (COPECs)

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The ERA prepared for the SWP identified the COPECs which were evaluated in the ERA based
on pooled datasets from 1995 and 1996 (Clean Harbors, 1998), 2003 (RETEC, 2003) and 2004
split samples (TRC, 2004).

The following ecologically-relevant Murphy Wetland areas of interest (AOIs) were identified:

Seasonally Ponded Area

Forested/Shrub Wetland

In order to select COPECs, maximum detected chemical concentrations were compared to
medium-specific screening benchmarks for surface water, wetland sediment, and wetland soil.
An analyte was retained as a COPEC if (a) the maximum concentration equaled or exceeded the
screening benchmark, or (b) it did not have a screening benchmark. A chemical was eliminated
as a COPEC if it's maximum detected concentration was less than the screening benchmark.

Benchmark comparisons in the ERA characterized possible risk to invertebrates at the Seasonally
Ponded Area in surface water due to aluminum, cyanide, iron, and manganese (Table G-14) and
in wetland sediment due to five Volatile Organic Compounds (VOCs), 21 Semi-Volatile Organic
Compounds (SVOCs), PCB congeners, PCB Aroclors, five pesticides, and 20 inorganics (Table
G-15). In addition, the preliminary screening of COPECs in the ERA selected COPECs in
wetland surface soils sampled from the forested/shrub wetland. PCB Aroclors and 13 inorganics
were initially retained as wetland surface soil COPECs (Table G-16).

Section 2: Exposure Assessment

The 13.3 acre SWP is located adjacent to Salem Street in the City of Woburn, Massachusetts and
encompasses three distinct properties consisting of the Aberjona, Whitney and Murphy
Properties. A small forested/scrub-shrub wetland area and an intermittent stream are present
within the northern portion of the Whitney Property while a seasonally ponded area is located
immediately adjacent on the Murphy Property. This wetland is referred to as the Murphy
Wetland. The seasonally ponded cover type extends over an area of approximately 0.8 acres
while the forested/scrub-shrub wetland totals approximately 0.9 acres in extent. With the
exception of the Murphy Wetland that is present on both the Murphy and Whitney Properties, no
other significant habitat exists on the SWP. The remaining portions of these parcels and the
Aberjona Property consist of occupied buildings, scrapped automobiles, wood/metal debris, and
pavement/barren dirt areas. These areas were not evaluated in the ERA as they offer little viable
habitat to ecological receptors.

The ERA was completed to estimate the risk of ecological harm associated with SWP-related
COPECs in wetland surface soil as well as surface water and wetland sediment. Ecological risks
were evaluated if the growth, survival, or reproduction of aquatic invertebrates, wetland birds,
and wetland mammals could be significantly affected by SWP-related contamination in aquatic
habitats (Seasonally Ponded Area) and/or terrestrial habitats (Forested/Shrub Wetland).

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Complete exposure pathways identified in the ERA included: the uptake of COPECs from
wetland sediment, surface water, and wetland soil through roots (vegetation); ingestion of
COPECs bound to wetland soil (terrestrial mammals); ingestion of COPECs bound to wetland
sediment (benthic invertebrates, semi-aquatic wetland birds and mammals); ingestion of
dissolved and particulate COPECs in surface water (aquatic invertebrates, semi-aquatic wetland
birds and mammals); ingestion of COPECs through consumption of contaminated plants
(herbivores and omnivores); and ingestion of COPECs through consumption of contaminated
invertebrate prey (insectivores).

Table G-17 summarizes the receptor groups and assessment/measurement endpoints evaluated
in the ERA.

The Massachusetts Natural Heritage and Endangered Species Program (MANHESP; 2009)12 was
consulted regarding the presence of state-listed rare, threatened, or endangered species and
priority habitat at and in the vicinity of the SWP during the preparation of the ERA. The
MANHESP indicated that there are no state-listed species known to occur in the project area
(MANHESP, 2009).

Exposure Point Concentrations (EPCs) for COPECs in surface water, wetland sediment, and prey
were calculated in terms of maximum exposures and Central Tendency Exposures (CTEs). CTE
is a reasonable representation of the likely concentration to which a population of receptors
would be exposed. CTE EPCs were calculated as the arithmetic mean. Maximum EPCs were
represented by the maximum concentrations of each COPEC.

Exposure of terrestrial and wetland wildlife (i.e., birds and mammals) to COPECs was estimated
using food chain models. Biological tissue concentrations within plants and representative prey
species, such as aquatic and terrestrial invertebrates were estimated to provide tissue data to be
incorporated into the food chain models. Surface water, wetland sediment, wetland soil, and
tissue EPCs were entered into the food chain model to calculate an estimated daily intake (EDI)
to which the receptor may be exposed. EPCs for prey items were estimated using biota-sediment
accumulation factors (BSAFs) or bioaccumulation factors (BAFs) derived from the literature.

Food chain modeling was used to calculate COPEC-specific EDIs for the herbivorous,
insectivorous and omnivorous wildlife receptors foraging in the aquatic and terrestrial habitats at
the SWP. The food chain models quantified the EDIs by calculating the intake of COPECs via
food ingestion, surface water drinking, and incidental wetland soil or wetland sediment
ingestion, which were considered the primary exposure routes.

Section 3: Ecological Effects Assessment

12 MANHESP, 2009. Massachusetts Natural Heritage and Endangered Species Program, Letter dated June 22, 2009
from Thomas W. French, PhD, Assistant Director, Division of Fisheries and Wildlife, Field Headquarters,
Westborough, MA to Antony Rodolakis, MACTEC.

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In aquatic habitats, effects assessments included comparison of surface water concentrations to
published chronic surface water benchmarks and to a reference wetland, and comparison of
concentrations of COPECs in wetland sediment to published sediment benchmarks and from a
reference wetland sediment.

Food chain models were used to compare the EDIs for herbivorous semi-aquatic mammals
(muskrat), omnivorous waterfowl (mallard), and insectivorous small mammals (short-tailed
shrew), based on exposure in the Seasonally Ponded Area, to published wildlife toxicity
reference values (TRVs) and to reference wetland conditions. For the terrestrial habitat provided
by the forested/shrub wetland, a food chain model for the insectivorous short-tailed shrew was
used to compare an EDI to a mammalian TRV.

Section 4: Ecological Risk Characterization

The following risk characterization includes a brief summary of the environmental risks
associated with the relevant media, the basis of these risks, and how these risks were determined
in the ERA. The ERA compared SWP data (exposure point concentrations) to ecotoxicological
benchmark and reference wetland values as well as food chain modeling. The conclusions of the
ERA are summarized below for each of the exposure areas where it was determined that
ecological risk may be present.

Hazard Quotients (HQs) were calculated to determine risk to (a) aquatic receptors directly
exposed to surface water and wetland sediment, and (b) wildlife species exposed to contaminated
media, plus prey items. An HQ shows how much the concentration of a COPEC exceeds its
benchmark or TRV. HQs were calculated as follows:

HQ = EPC / benchmark or TRV

The EPC can be based on either a maximum exposure or CTE scenario.

The risk characterization also includes an evaluation of reference wetland concentrations to the
overall SWP risks. A summary of the risk conclusions within the Seasonally Ponded Area and
Forested/Shrub Wetland is presented in Table G-18.

Seasonally Ponded Area

The aquatic invertebrate endpoints suggest that there may be impacts from COPECs on
invertebrate communities inhabiting the seasonally ponded area. The strength of the evidence
was based entirely on exceedances of surface water and sediment-effects benchmarks. Risk from
detected COPECs to the aquatic macroinvertebrate community from the detected COPECs
within the surface waters of the Seasonally Ponded Area were initially identified using total
recoverable mean concentrations. Though this evaluation, aluminum, barium, cyanide, iron and
manganese exceed their respective chronic benchmarks. However, none of the five COPECs
exceeds its respective acute benchmark and mean concentrations of aluminum, iron and

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manganese are greater in the reference wetland surface water. Barium was not detected above an
alternative USEPA-reported effect level. Cyanide was detected slightly above its chronic
benchmark at two of the three surface water samples collected from the Seasonally Ponded Area.

The potential for ecological risk to the benthic invertebrate community in the Seasonally Ponded
Area was identified by comparing concentrations of the COPECs in wetland sediment with
benchmarks protective of benthic biota and sediment concentrations of these COPECs detected
in the reference wetlands. PCB Aroclors, chromium, lead and zinc were identified as the major
risk drivers as the mean concentrations of these COPECs exceed sediment benchmarks
associated with severe or probable effect concentrations. Food chain models characterized risk
to the mallard duck at the Seasonally Ponded Area as unlikely. Food chain models suggest that
risk to muskrat is possible from mean PCB and chromium concentrations in the wetland
sediment. Food chain models also suggest that in the wetland sediment of the Seasonally Ponded
Area, risk to shrews is also possible from PCBs and chromium.

The refined list of Contaminants of Ecological Concern (COECs) in the Seasonally Ponded Area,
along with recommended protective levels and the basis for each level, are presented in Table G-
19.

Forested/Shrub Wetland

Based on the results of the ERA, it was concluded that risks to shrews inhabiting the
Forested/Shrub Wetland are likely due to mean concentrations of PCBs and chromium. The
refined list of COECs in the Forested/Shrub Wetland, along with recommended protective levels
and the basis for each level, are presented in Table G-19.

Section 5: Uncertainties

There is uncertainty associated with estimates of risk in any ERA because the risk estimates are
based on a number of assumptions regarding exposure and toxicity. More specifically, there is
inherent variability and uncertainty associated with the data collected to characterize exposure
concentrations and assumptions about the bioavailability of the selected COPECs. There are also
assumptions and limitations inherent in food chain modeling, including selection of exposure and
modeling parameters (e.g., dietary intake, body weight, and age), uptake factors, and
toxicological data (e.g., TRVs).

The food chain models assumed that 100% of the metals ingested are absorbed. SWP-specific
prey tissue data were unavailable for benthic macroinvertebrates and plants at the Seasonally
Ponded Area and the Forested/Shrub Wetland. SWP-specific tissue data would reduce
uncertainty and result in greater confidence in the risk estimation because they are direct
measures of potential exposures to receptors.

Overall, the conservative nature of the food chain models likely overestimate risk associated
wetland sediment COPECs.

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Toxicity values for indicator species and communities were based on literature values which
represents a major source of uncertainty in the ERA. The sensitivity of receptors at the SWP
may be different than the sensitivity of species used in tests reported in the literature. The results
of different studies often varied several orders of magnitude, based on using various forms of the
COPEC, different species, and different endpoints. One of the largest sources of uncertainty in
all of these TRV values is the form of the chemical used to determine the laboratory exposure.
The HQ approach uses the assumption that the absorption of the chemical from the diet will be
the same as the absorption of the chemical in the form used in the laboratory. Often this
assumption is very conservative, because laboratory studies use readily-dissolved forms of
metals, which are more readily absorbed than metals ingested via consumption of contaminated
sediment and/or plants.

3. Basis for Response Action

The baseline human health and ecological risk assessments determined that future recreational
users, construction workers, residents or ecological receptors potentially exposed to COCs in
soil, wetland sediment/soil, or groundwater via direct contact, ingestion, or inhalation may
present an unacceptable human health or ecological risk. Therefore, the current and potential
future releases of hazardous substances from the SWP, if not addressed by implementing the
response action selected in this ROD, may present an imminent and substantial endangerment to
public health, welfare, or the environment. Remedial actions are focused on the following
media: surface and subsurface soils at the Abeijona, Whitney and Murphy Properties, wetland
sediments/soils at the Murphy Wetland, and SWP-wide groundwater

Leaching of volatile and petroleum-related (C5-C8 aliphatic, C9-C12 aliphatic, C9-C18
aliphatic, C9-C10 aromatic, and C11-C22 aromatic) contaminants from soil to groundwater was
evaluated in the 2016 FS Report, where leaching-based Preliminary Remediation Goals (PRGs)
for soil above the water table are exceeded. Soils above the water table in various areas of the
SWP, including the Murphy, Whitney and Abeijona Properties, exceeded the leaching-based
PRGs. Details of the leaching evaluation can be found in the 2016 FS Report and 2017 FS
Report Addendum - Technical Memorandum.

Although the risk assessment did not evaluate the risk associated with NAPL and no risk-based
PRGs have been developed for NAPL, NAPL serves as a continuing source of contamination to
groundwater as contaminants leach/dissolve from the NAPL and migrate to groundwater.
Therefore, the remedy addresses NAPL.

H. REMEDIATION OBJECTIVES

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Remedial Action Objectives (RAOs) are medium-specific goals that define the objective of
remedial actions to protect human health and the environment. RAOs specify the potential
exposure routes and receptors and provide a general description of what the cleanup will
accomplish. The RAOs are based on available information and standards, such as ARARs, to-be-
considered (TBC) guidance, and site-specific risk-based levels. The COCs are presented in
Tables Gs (Appendix B) and the cleanup levels are presented in Tables LI through L4
(Appendix B). These RAOs were developed to mitigate, restore and/or prevent existing and
future potential threats to human health and the environment.

The RAOs for the selected remedy for the SWP are:

Soil:

• Murphy Property:

1) Prevent direct human contact/ingestion/inhalation with contaminated soils that exceed
ARAR and risk-based standards.

2) Prevent soil leaching and resulting contaminant migration to groundwater in excess of
leaching-based standards.

3) Prevent migration of contaminated soil to wetlands and adjoining properties.

• Aberjona Property (excluding Existing Aberjona Residence):

1) Prevent direct human contact/ingestion/inhalation with contaminated soils that exceed
risk-based standards.

2) Prevent soil leaching and resulting contaminant migration to groundwater in excess of
leaching-based standards.

3) Prevent migration of contaminated soil to wetlands and adjoining properties.

• Whitney Property:

1) Prevent direct human contact/ingestion/inhalation with contaminated soils that exceed
ARAR and risk-based standards.

2) Prevent soil leaching and resulting contaminant migration to groundwater in excess of
leaching-based standards.

3) Prevent migration of contaminated soil to wetlands and adjoining properties.
Groundwater:

1) Prevent human exposure to groundwater containing concentrations of contaminants in
excess of the ARAR and risk-based standards.

2) Prevent or minimize migration of contaminants in groundwater.

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3) Restore groundwater to its beneficial use by attaining ARAR and risk-based
standards.

NAPL:

1) Remove and/or contain NAPL and residual NAPL to the extent practicable, as a
source control measure.

2) Prevent human exposure to NAPL containing concentrations of contaminants that
contribute to exceedances of groundwater and/or soil ARAR and risk-based
standards.

3) Prevent NAPL migration, leaching to groundwater, and discharge to wetlands.

Wetland Sediment/Soil - Murphy Wetland:

1) Prevent direct human contact with contaminated wetland sediments/soils that exceed
ARAR and risk-based standards.

2) Prevent exposure of ecological receptors to contaminants in wetland sediments/soils
that present an unacceptable ecological risk.

Soil Gas:

1) Prevent human exposure to volatile compounds that would pose an inhalation risk.

I. DEVELOPMENT AND SCREENING OF ALTERNATIVES

A. Statutory Requirements/Response Objectives

Under its legal authorities, EPA's primary responsibility at Superfund sites is to undertake
remedial actions that are protective of human health and the environment. In addition, Section
121 of CERCLA establishes several other statutory requirements and preferences, including: 1) a
requirement that EPA's remedial action, when complete, must comply with all federal and more
stringent state environmental and facility siting standards, requirements, criteria or limitations,
unless a waiver is invoked; 2) a requirement that EPA select a remedial action that is cost-
effective, and that utilizes permanent solutions and alternative treatment technologies or resource
recovery technologies to the maximum extent practicable; and 3) a preference for remedies in
which treatment that permanently and significantly reduces the volume, toxicity or mobility of
the hazardous substances is a principal element over remedies not involving such treatment.
Response alternatives were developed to be consistent with these Congressional mandates.

B. Technology and Alternative Development and Screening

CERCLA and the NCP- set forth the process by which remedial actions are evaluated and
selected. In accordance with these requirements, a range of alternatives were developed for the
SWP.

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With respect to source control, the RI/FS and 2017 FS Report Addendum - Technical
Memorandum developed a range of alternatives in which treatment that reduces the toxicity,
mobility, or volume of the hazardous substances is a principal element. This range included an
alternative that removes or destroys hazardous substances to the maximum extent feasible,
eliminating or minimizing to the degree possible the need for long term management. This range
also included alternatives that treat the principal threats posed by the SWP, but vary in the degree
of treatment employed and the quantities and characteristics of the treatment residuals and
untreated waste that must be managed; alternative(s) that involve little or no treatment but
provide protection through engineering or Institutional Controls; and a no action alternative.

With respect to ground water response action, the RI/FS and the 2017 FS Report Addendum -
Technical Memorandum developed a number of remedial alternatives that attain site specific
remediation levels within different timeframes using different technologies; and a no action
alternative.

As discussed in Section 3 of the FS Report, soil, SWP-wide groundwater, NAPL and wetland
sediment/soil treatment technology options were identified, assessed and screened based on
implementability, effectiveness, and cost. These technologies were combined into source control
(SC) and management of migration (MM) alternatives. The 2017 FS Report Addendum -
Technical Memorandum and Section 4 of the FS presented the remedial alternatives developed
by combining the technologies identified in the previous screening process in the categories
identified in Section 300.430(e)(3) of the NCP. The purpose of the initial screening was to
narrow the number of potential remedial actions for further detailed analysis while preserving a
range of options. Each alternative was then evaluated in detail in the 2017 FS Report Addendum
- Technical Memorandum and in Sections 5 and 6 of the FS.

In summary, of the 47 source control and management of migration remedial technologies
screened in Section 3 of the FS for all impacted media including soil, SWP-wide groundwater,
NAPL and wetland sediment/soil, 23 were retained as possible options for the cleanup of the
SWP. From this initial screening, remedial options were combined, and 26 source control and
management of migration alternatives were selected for detailed analysis. Although the
alternatives are media-specific, the media and alternatives are interrelated such that one
alternative for a particular medium may impact the remedial alternative options for other media.
For example, since soil impacts and NAPL (e.g., Northern Whitney Soil Area) result in the
migration of COCs to groundwater, any groundwater alternative would be dependent upon the
actions taken to eliminate principal threat wastes associated with soil and NAPL, otherwise the
efficiency, effectiveness and timeframe for cleanup of the groundwater remedy could be
compromised.

J. DESCRIPTION OF ALTERNATIVES

This Section provides a narrative summary of each source control and management of migration

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alternative evaluated. Refer to Section K of this ROD for a breakdown of costs (including
capital and O&M), as well as discussion on the time to construct and meet RAOs, for each
alternative.

1. Source Control Alternatives Analyzed

The source control alternatives analyzed for the SWP include:

Soil Alternatives (evaluated individually for the Whitney (SW), Murphy (SM) and Abeijona
(SA) Properties)

•	SW-l/SM-l/SA-1: No Action

•	SW-2/SM-2/SA-2: Capping and Institutional Controls

•	SW-3/SM-3/SA-3: Soil Excavation, Off-site Disposal, Capping, and Institutional Controls

•	SW-4/SM-4/SA-4: Soil Excavation, Off-site Disposal, Cover and Institutional Controls13

NAPL Alternatives

•	N-l: No Action

•	N-2: NAPL Skimming/Recovery and Institutional Controls

•	N-3: Excavation and Off-Site Disposal

Murphy Wetland Sediment/Soil Alternatives

•	WTL-1: No Action

•	WTL-2: Monitored Natural Recovery and Institutional Controls

•	WTL-3: Capping, Wetland Mitigation, Monitoring and Institutional Controls

•	WTL-4: Shallow (1 Foot) Excavation and Targeted Deeper (3 Feet) Excavation, Off-Site
Disposal, Amended Cap, Wetland Restoration, Monitoring and Institutional Controls

•	WTL-5: Deep (3 Feet) Excavation and Off-Site Disposal, Backfill, and Wetland Restoration

Each of the 20 source control alternatives is summarized below. A more complete, detailed
presentation of each alternative is found in the 2017 FS Report Addendum - Technical
Memorandum and Section 5 of the FS.

Soil Alternatives

13 A cover is not required as part of the remedy for the Abeijona Property (Alternative SA-4).
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Whitney Soil Alternatives The Whitney Property soils include significantly contaminated soil at
the "Northern Whitney Soil Area" and lesser contaminated soils (which exceeds preliminary
remediation goals) on the remainder of the Whitney Property. Both types of soil are addressed by
the alternatives under this section, except for the No Action Alternative. "Significantly
contaminated soil" is defined as soil with contaminant concentrations 10 times greater that the soil
cleanup levels and/or greater than or equal to 50 mg/kg (equivalent to ppm) of PCBs.

With the exception of the No Action (SW-1) alternative, each of the alternatives for Whitney Soil
includes a pre-design investigation to further define the horizontal and vertical extent of soil
contamination, all appropriate plans and specifications (e.g., air monitoring plan, transportation
plan, dust and odor control plan, soil management plan, restoration plan, demolition plan for
existing buildings, erosion and sedimentation control plan, trucking plan, and/or health and safety
plan), and all necessary preparation and mobilization activities (e.g., removal of trees and other
vegetation, removal of large debris, relocation of business equipment and materials, installation of
temporary fencing, decontamination facilities, soil stockpile areas, trailer, and/or sanitation
facilities).

SW-1: No Action

Under the no action alternative, no additional actions would be taken to address exposure to soils
at the Whitney Property. The No Action Alternative does not include active remediation or
institutional controls and the current levels of contaminants in soil are assumed to remain
unchanged. As required by CERCLA, five-year reviews would still be performed as part of the
No Action Alternative. As required by the CERCLA and the NCP, the No Action Alternative
serves as a baseline for comparing the effectiveness of other remedial alternatives for soils.
Except for the cost of statutorily-required five-year reviews, there is no cost associated with this
alternative.

SW-2: Capping and Institutional Controls

Under this alternative, all soils exceeding cleanup levels would be covered with an impermeable
cap designed to prevent direct contact with impacted soils, to prevent soil from being carried to
the wetland or neighboring properties during rain events via erosion, and/or to prevent soil
contaminants from leaching to groundwater. The cap would be adequately designed with long-
term integrity for seasonal conditions, severe storms (up to a 500-year storm event), and
freeze/thaw conditions; to satisfy ARAR requirements (e.g., TSCA); and prevent contaminant
leaching to groundwater (i.e. meet impermeability requirements). Flood storage loss due to
capping would require mitigation nearby within the waterway. Additional mitigation measures
may be required to address any additional long- or short-term floodplain impairment within the
500-year floodplain. This alternative also includes long-term monitoring and maintenance of the
capped areas as well as Institutional Controls to insure the cap is maintained; prohibit residential,
school, and daycare use, and guard against the future vapor intrusion pathway. Five-year reviews

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will be required since contamination will be left in place. The time to achieve RAOs is estimated
to be on the order of 12 weeks. The total estimated cost of this alternative is approximately $2.3
million.

SW-3: Soil Excavation and Off-site Disposal for Northern Whitney Soil Area, Capping, and
Institutional Controls

Under this alternative, the significantly contaminated soils exceeding cleanup levels (i.e. 10 times
greater than the soil cleanup level and/or greater than or equal to PCBs at 50 mg/kg (ppm)) at the
Whitney Northern Soil Area (estimated to be approximately 5,400 cubic yards at the Whitney
Property) would be excavated and disposed of at an approved off-site facility. Excavated materials
will be managed so as to not impair resources within the 500-year floodplain or adjacent wetlands,
to the extent practicable. Mitigation measures may be required to address any unavoidable long-
or short-term impairment within the 500-year floodplain. Excavated areas would then be
backfilled with clean soils and an impermeable cap installed over areas with remaining subsurface
soil contamination. The cap will be installed at grade so there will not be any net loss of floodplain
storage. The clean backfill material placed in the Northern Whitney Soil Area would include
mixing amendments (e.g., ZVI) below the water table to reduce soil and local groundwater
concentrations and support groundwater cleanup (i.e., in the Northern Whitney Soil Area). Due
to the depth of the excavation, shoring would also be installed in the Northern Whitney Soil Area
to prevent collapse of the sidewalls and impacts to the wetland/floodplain. Dewatering and
appropriate treatment of the extracted groundwater and any water removed from dewatering
saturated soils will be required in association with excavations below the groundwater table. The
remaining soils exceeding cleanup levels (estimated to be approximately 70,000 square feet) would
be covered with an impermeable cap designed to prevent direct contact with impacted soils, to
prevent soil from being carried to the wetland or neighboring properties during rain events via
erosion or flooding, and/or to prevent soil contaminants from leaching to groundwater (i.e., meet
impermeability requirements). Shallow excavation would occur in areas subject to capping
(outside of the area of significantly contaminated soils) (estimated to be approximately 5,200 cubic
yards) to facilitate cap placement without a net loss of floodplain storage. This excavated material
(a total of 10,600 cubic yards) would also be transported off-site for disposal. The large building
located at the center of the Whitney Property will likely require complete demolition, to be
determined post-ROD during Remedial Design. The cap will be adequately designed with long-
term integrity for seasonal conditions, severe storms (up to a 500-year storm event), and
freeze/thaw conditions; to satisfy ARAR requirements (e.g., TSCA); to prevent flood storage loss;
and prevent contaminant leaching to groundwater (i.e. meet impermeability requirements).
Existing structures (e.g., concrete foundations and slabs) may be evaluated during the Remedial
Design process for potentially satisfying cap requirements. This alternative also includes long-
term monitoring and maintenance of the capped areas as well as Institutional Controls to insure
the cap is maintained; prohibit residential, school, and daycare use; and guard against the future
vapor intrusion pathway. Five-year reviews will be required since contamination will be left in
place. The time to achieve RAOs is estimated to be on the order of 7 months. The total estimated
cost of this alternative is approximately $7.0 million.

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SW-4: Soil Excavation, Off-site Disposal, Cover and Institutional Controls

This alternative includes the excavation of the Northern Whitney Soil Area (5,400 cubic yards,
consistent with Alternative SW-3) and all soils exceeding cleanup levels above the water table
(estimated to be approximately 16,400 cubic yards) and disposal of these excavated materials at
an approved off-site disposal facility. Excavated materials (a total of approximately 21,800
cubic yards) will be managed so as to not impair resources within the 500-year floodplain or
adjacent wetlands, to the extent practicable. Mitigation measures may be required to address any
unavoidable long- or short-term impairment within the 500-year floodplain. Buildings will
require complete demolition. Shoring, dewatering and extracted water treatment would be
necessary in association with the implementation of this alternative. Excavated areas would then
be backfilled with clean soils to serve as a protective cover, and amendments (e.g., ZVI) would
be mixed below the water table to reduce soil and local groundwater concentrations and support
groundwater cleanup (i.e., in the Northern Whitney Soil Area). This alternative also includes
Institutional Controls to manage deeper soils that exceed cleanup levels; prohibit residential,
school, and daycare use; and guard against the future vapor intrusion pathway. Five-year
reviews will be required since contamination will be left in place. The time to achieve RAOs is
estimated to be on the order of 6 to 12 months. The total estimated cost of this alternative is
approximately $9.8 million.

Murphy Soil Alternatives Except for the No Action Alternative, the alternatives for the Murphy
Property address direct contact exposure to thallium in soil and the leaching of VOCs and
applicable petroleum fractions from soil to groundwater.

With the exception of the No Action (SM-1) alternative, each of the alternatives for Murphy Soil
includes a pre-design investigation to better define the extent of COCs exceeding the soil PRGs,
all appropriate plans and specifications (e.g., air monitoring plan, transportation plan, dust and
odor control plan, soil management plan, restoration plan, demolition plan for existing buildings,
erosion and sedimentation control plan, trucking plan, and/or health and safety plan) and all
necessary preparation and mobilization activities (e.g., removal of trees and other vegetation,
removal of large debris, relocation of business equipment and materials, installation of temporary
fencing, decontamination facilities, soil stockpile areas, trailer, and/or sanitation facilities).

SM-1: No Action

Under the No Action Alternative, no additional actions would be taken to address exposure to
soils at the Whitney Property. The No Action Alternative does not include active remediation or
institutional controls and the current levels of contaminants in soil are assumed to remain
unchanged. As required by CERCLA, five-year reviews would still be performed as part of the
No Action Alternative. As required by CERCLA and the NCP, the No Action Alternative serves
as a baseline for comparing the effectiveness of other remedial alternatives for soils. Except for
the cost of statutorily-required five-year reviews, there is no cost associated with this alternative.

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SM-2: Capping and Institutional Controls

Under this alternative, all soils exceeding cleanup levels would be covered with an impermeable
cap designed to prevent direct contact with impacted soils, to prevent soil from being carried to
the wetland or neighboring properties during rain events via erosion, and/or to prevent soil
contaminants from leaching to groundwater. The cap would be adequately designed with long-
term integrity for seasonal conditions, severe storms (up to a 500-year storm event), and
freeze/thaw conditions; to satisfy ARAR requirements (e.g., TSCA and/or RCRA); and prevent
contaminant leaching to groundwater (i.e. meet impermeability requirements). Flood storage loss
due to capping would require mitigation nearby within the waterway. Additional mitigation
measures may be required to address any additional long- or short-term floodplain impairment
within the 500-year floodplain. This alternative also includes long-term monitoring and
maintenance of the capped areas as well as Institutional Controls to insure the cap is maintained;
prohibit residential, school, and daycare use; and guard against the future vapor intrusion pathway.
Five-year reviews will be required since contamination will be left in place. The time to achieve
RAOs is estimated to be on the order of 12 weeks. The total estimated cost of this alternative is
approximately $1.8 million.

SM-3: Soil Excavation, Off-Site Disposal, Capping and Institutional Controls

Under this alternative, soils exceeding cleanup levels (estimated to be approximately 93,500
square feet) would be covered with an impermeable cap designed to prevent direct contact with
impacted soils, to prevent soil from being carried to the wetland or neighboring properties during
rain events via erosion or flooding, and/or to prevent soil contaminants from leaching to
groundwater (i.e. meet impermeability requirements). Shallow excavation would occur in areas
subject to capping (estimated to be approximately 6,900 cubic yards) to facilitate cap placement
without a net loss of floodplain storage. This excavated material would be transported off-site for
disposal. The cap will be adequately designed with long-term integrity for seasonal conditions,
severe storms (up to a 500-year storm event), and freeze/thaw conditions; to satisfy ARAR
requirements (e.g., TSCA and/or RCRA); to prevent flood storage loss; and prevent contaminant
leaching to groundwater (i.e. meet impermeability requirements). Existing structures (e.g.,
concrete foundations and slabs) may be evaluated during the Remedial Design process for
potentially satisfying cap requirements. This alternative also includes long-term monitoring and
maintenance of the capped areas as well as Institutional Controls to insure the cap is maintained;
prohibit residential, school, and daycare use; and guard against the future vapor intrusion
pathway. Five-year reviews will be required since contamination will be left in place. The time
to achieve RAOs is estimated to be on the order of 12 weeks. The total estimated cost of this
alternative is approximately $3.0 million.

SM-4: Soil Excavation, Off-Site Disposal, Cover and Institutional Controls

This alternative includes the excavation of all soils exceeding cleanup levels above the water

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table (estimated to be approximately 26,500 cubic yards) and disposal of these excavated
materials at an approved off-site disposal facility. Excavated materials will be managed so as to
not impair resources within the 500-year floodplain or adjacent wetlands, to the extent
practicable. Mitigation measures may be required to address any unavoidable long- or short-
term impairment within the 500-year floodplain. Buildings will require complete demolition.
Shoring, dewatering and extracted water treatment would be necessary in association with the
implementation of this alternative. Excavated areas would then be backfilled with clean soils.
This alternative also includes Institutional Controls to manage deeper soils that exceed cleanup
levels; prohibit residential, school or daycare use; and guard against the future vapor intrusion
pathway. Five-year reviews will be required since contamination will be left in place. The time
to achieve RAOs is estimated to be on the order of 6 to 12 months. The total estimated cost of
this alternative is approximately $11.4 million.

Aberjona Soil Alternatives Except for the No Action Alternative, the alternatives for soil at the
Aberjona Property address leachability of VOCs and applicable petroleum fractions from soil to
groundwater.

With the exception of the No Action (SA-1) alternative, each of the alternatives for Aberjona Soil
includes a pre-design investigation to better define the extent of COCs exceeding the soil PRGs,
all appropriate plans and specifications (e.g., air monitoring plan, transportation plan, dust and
odor control plan, soil management plan, restoration plan, demolition plan for existing buildings,
erosion and sedimentation control plan, trucking plan, and/or health and safety plan) and all
necessary preparation and mobilization activities (e.g., removal of trees and other vegetation,
removal of large debris, relocation of business equipment and materials, installation of temporary
fencing, decontamination facilities, soil stockpile areas, trailer, and/or sanitation facilities).

SA-1: No Action

Under the No Action Alternative, no additional actions would be taken to address exposure to
soils at the Whitney Property. The No Action Alternative does not include active remediation or
institutional controls and the current levels of contaminants in soil are assumed to remain
unchanged. As required by CERCLA, five-year reviews would still be performed as part of the
No Action Alternative. As required by CERCLA and the NCP, the No Action Alternative serves
as a baseline for comparing the effectiveness of other remedial alternatives for soils. Except for
the cost of five-year reviews, there is no cost associated with this alternative.

SA-2: Capping and Institutional Controls

Under this alternative, all soils exceeding cleanup levels would be covered with a cap designed to
prevent direct contact with impacted soils, to prevent soil from being carried to the wetland or
neighboring properties during rain events via erosion, and/or to prevent soil contaminants from
leaching to groundwater. The cap would be adequately designed with long-term integrity for
seasonal conditions, severe storms (up to a 500-year storm event), and freeze/thaw conditions; to

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satisfy ARAR requirements (e.g., TSCA and/or RCRA); and prevent contaminant leaching to
groundwater (i.e. meet impermeability requirements). Flood storage loss due to capping would
require mitigation nearby within the waterway. Additional mitigation measures may be required
to address any additional long- or short-term floodplain impairment within the 500-year floodplain.
This alternative also includes long-term monitoring and maintenance of the capped areas as well
as Institutional Controls to insure the cap is maintained; prohibit residential, school and daycare
use (except on the Existing Aberjona Residence area); and guard against the future vapor intrusion
pathway. Five-year reviews will be required since contamination will be left in place. The time to
achieve RAOs is estimated to be on the order of 4 weeks. The total estimated cost of this
alternative is approximately $0.16 million.

SA-3: Soil Excavation, Off-Site Disposal, Capping and Institutional Controls

Under this alternative, soils exceeding cleanup levels (estimated to be approximately 3,600
square feet) would be covered with an impermeable cap designed to prevent direct contact with
impacted soils, to prevent soil from being carried to the wetland or neighboring properties during
rain events via erosion or flooding, and/or to prevent soil contaminants from leaching to
groundwater (i.e. meet impermeability requirements). Shallow excavation would occur in areas
subject to capping (estimated to be approximately 300 cubic yards) to facilitate cap placement
without a net loss of floodplain storage. This excavated material would also be transported off-
site for disposal. The cap will be adequately designed with long-term integrity for seasonal
conditions, severe storms (up to a 500-year storm event), and freeze/thaw conditions; to satisfy
ARAR requirements (e.g., TSCA and/or RCRA); to prevent flood storage loss; and prevent
contaminant leaching to groundwater (i.e. meet impermeability requirements). Existing
structures (e.g. concrete foundations and slabs) may be evaluated during the Remedial Design
process for potentially satisfying cap requirements. This alternative also includes long-term
monitoring and maintenance of the capped areas as well as Institutional Controls to insure the
cap is maintained; prohibit residential, school and daycare use (except on the Existing Abeijona
Residence area); and guard against the future vapor intrusion pathway. Five-year reviews will be
required since contamination will be left in place. The time to achieve RAOs is estimated to be
on the order of 12 weeks. The total estimated cost of this alternative is approximately $0.41
million.

SA-4: Soil Excavation, Off-Site Disposal, Cover and Institutional Controls

This alternative includes the excavation of all soils exceeding cleanup levels above the water
table (estimated to be approximately 800 cubic yards for Abeijona Property) and disposal of
these excavated materials at an approved off-site disposal facility. Excavated materials will be
managed so as to not impair resources within the 500-year floodplain or adjacent wetlands, to the
extent practicable. Mitigation measures may be required to address any unavoidable long- or
short-term impairment within the 500-year floodplain. The commercial building on the Abeijona
Property may require complete or partial demolition. Shoring, dewatering and extracted water
treatment would be necessary in association with the implementation of this alternative. This

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alternative also includes Institutional Controls to manage deeper soils that exceed cleanup levels,
prohibit residential, school, and daycare use (except on the Existing Abeijona Residence), and
guard against the future vapor intrusion pathway. Five-year reviews will be required since
contamination will be left in place. The time to achieve RAOs is estimated to be on the order of 6
to 12 months. The total estimated cost of this alternative is approximately $0.63 million.

NAPL Alternatives
N-l: No Action

Alternative N-l is the No Action Alternative. This alternative provides No Action to address this
source of contamination to environmental media, particularly groundwater and soil. As required
by CERCLA, five-year reviews would still be performed as part of the No Action Alternative. As
required by the CERCLA and the NCP, the No Action Alternative serves as a baseline for
comparing the effectiveness of other remedial alternatives to be developed for NAPL. Except for
the cost of five-year reviews, there is no cost estimated as part of this alternative.

N-2: NAPL Skimming and Institutional Controls

Alternative N-2 includes automatic skimming of NAPL from monitoring wells within the NAPL
areas at the Whitney and Murphy Properties and an excavated recovery trench, NAPL recovery
into drums for off-site disposal, and institutional controls. The recovery trench will improve the
efficiency of NAPL removal and protect the wetland from continuing impacts by intercepting
NAPL before discharge to the wetland occurs. Contaminated soils excavated from the trench will
be managed so as to not impair resources within the 500-year floodplain or adjacent wetlands, to
the extent practicable. Dewatering and extracted water treatment may be necessary in association
trench construction and management of the excavated soil/NAPL. Mitigation measures may be
required to address any unavoidable long- or short-term impairment within the 500-year
floodplain. In some areas the design of the trench would need to be incorporated into the design
for any soil caps called for under the soil component of the remedy. The skimming system
would require long-term routine inspection and maintenance throughout implementation of this
cleanup approach. This alternative also includes the implementation of Institutional Controls
protect the collection trench and any other remedial infrastructure, to prohibit use of NAPL-
impacted groundwater; prohibit residential, school, and daycare use; and to control the future
vapor intrusion pathway until soil and groundwater cleanup levels are achieved. The duration
these controls would need to remain in place would be associated with the selected soil and
groundwater cleanup alternative. Five-year reviews will be required since contamination will be
left in place. The duration these controls would need to remain in place is uncertain, but is
anticipated to be in excess of 10 years. The estimated present value of this alternative is
approximately $0.76 million.

N-3: Excavation and Off-Site Disposal

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Alternative N-3 includes the excavation of NAPL areas at the Whitney and Murphy Properties,
and disposal of these excavated materials at an approved off-site disposal facility. The
excavation will extend below the water table (estimated 12 feet below the ground surface). The
excavation activities will collect approximately 6,000 cubic yards of NAPL-impacted soil.
Excavation would continue until sampling confirms that the NAPL is completely removed.
Excavated soils would be moved to a stockpile area and pre-conditioned (removal or absorption
of free water) for shipment to an off-site disposal facility. Shoring will be installed to prevent
collapse of the sidewalls, damage to nearby structures and impacts to the wetland/floodplain.
Excavated areas would then be backfilled with clean soils, and amendments (e.g., ZVI) would be
mixed below the water table to reduce soil and local groundwater concentrations and support
groundwater cleanup. Excavations/backfilling will be coordinated with the remedial
excavations/capping required under the soil component of the remedy. Mitigation measures may
be required to address any unavoidable long or short-term impairment within the 500-year
floodplain. Dewatering and appropriate treatment of the extracted water will be required in
association with excavations below the groundwater table, with discharge to the Abeijona River
or appropriate disposal off-site at licensed facility. Five-year review requirements triggered by
remnant NAPL that will be left behind will be addressed through review of the groundwater
component of the remedy. The time to achieve RAOs is estimated to be on the order of 4 weeks.
The estimated present value of this alternative is approximately $3.4 million.

Wetland Sediment/Soil Alternatives
WTL-1: No Action

Under the No Action Alternative, no additional actions would be taken to address exposure to
wetland sediment/soil. As required by CERCLA, five-year reviews would still be performed as
part of the No Action Alternative. As required by the CERCLA and the NCP, the No Action
Alternative serves as a baseline for comparing the effectiveness of other remedial alternatives to
be developed for wetlands. The current levels of contaminants in wetland sediment/soil are
assumed to remain unchanged. Except for the cost of five-year reviews, there is no cost
estimated as part of this alternative.

WTL-2: Monitored Natural Recovery (MNR) and Institutional Controls

Alternative WTL-2 involves monitoring the wetland for natural processes that contain, destroy or
reduce the bioavailability or toxicity of contaminants in wetland sediment/soil. The most
predominant natural process would be the gradual covering of the impacted wetland
sediment/soil with clean sediment/soil. The covered sediment/soil would then be inaccessible
for contact by recreational visitors or ecological receptors. This mechanism would take an
extended and uncertain timeframe to achieve cleanup levels in the top foot of wetland
sediment/soil. This alternative also includes Institutional Controls such as fencing to prevent
trespassing, signs warning to not enter or dig in the area, deed restrictions to control future
intrusive work (excavation and drilling for example), and routine inspections to assure the

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Institutional Controls are maintained. Institutional Controls will not address ongoing risks to
ecological receptors. Five-year reviews will be required since contamination will be left in
place. The estimated present value of this alternative is approximately $0.22 million.

WTL-3: Capping, Wetland Mitigation, Monitoring and Institutional Controls

Alternative WTL-3 involves actively filling in the wetland pond and scrub/shrub wetland areas
with clean fill (approximately 63,000 square foot area). The thickness of the cover would be
three feet to effectively isolate the high concentrations of lead, chromium, petroleum
hydrocarbons, and PCBs. The cap would be adequately designed with long-term integrity for
seasonal conditions, severe storms (up to a 500-year storm event), and freeze/thaw conditions; to
satisfy regulatory ARAR requirements (e.g. TSCA and/or RCRA); and prevent contaminant
leaching to groundwater (i.e. meet impermeability requirements). Native plantings appropriate to
the new ground elevation and degree of soil saturation would be installed. Placement of the cap
would change drainage patterns in the area. Installation of catch basins and transfer lines is
anticipated. Inspection and maintenance of the cap, plantings, and drainage features would be
required. Construction of at least 1.44-acre compensatory wetlands and floodplain mitigation in
another location within the waterway upstream of any sensitive floodplain receptors, would also
be required as raising the wetland area three feet will effectively eliminate the wetland habitat
and flood storage capacity of the wetland. Mitigation would also be required for any temporary
alteration of wetland/floodplain during cap construction. Native vegetation would be used for all
mitigation work. Institutional Controls would be implemented to ensure long-term cap integrity
and to prohibit intrusive activities unless properly controlled. Five-year reviews will be required
since contamination will be left in place. The time to achieve RAOs is estimated to be on the
order of 5 weeks. The estimated present value of this alternative is approximately $1.0 million.

WTL-4: Shallow (1 foot) Excavation and Targeted Deeper (3 feet) Excavation, Off-Site
Disposal, Amended Cap, Wetland Restoration, Monitoring and Institutional Controls

Alternative WTL-4 involves excavation of the top one foot of sediment/soil across the wetland,
excavation to 3 feet in areas with significantly elevated contaminant concentrations, off-site
disposal of excavated wetland sediment/soil, placement of an amended clean sediment/soil cap to
return the wetland to the original elevation and habitat type, plantings to restore the wetland, and
Institutional Controls. The final elevation of the cap would be the same as the pre-remediation
elevation. Native wetland plantings would be installed to restore the wetland habitat. The cap
would be adequately designed with long-term integrity for seasonal conditions, severe storms (up
to a 500-year storm event), and freeze/thaw conditions. Dewatering and appropriate treatment of
the extracted groundwater and any water removed from dewatering saturated sediments/soils will
be required in association with excavations below the groundwater table. Treated water will be
discharged to the Aberjona River or to an appropriate off-site, licensed disposal facility. An
estimated total of approximately 3,700 cubic yards of material would be excavated. This
estimate includes an additional approximately 1,400 cubic yards for deeper excavation in areas
of significantly elevated concentrations. Periodic monitoring would be performed to evaluate

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cap effectiveness and to confirm wetland sediment/soil used during restoration does not become
impacted by the underlying contamination. Long-term monitoring and Institutional Controls will
be required to ensure the cap remains protective. Five-year reviews will be required since
contamination will be left in place. The time to achieve RAOs is estimated to be on the order of 8
weeks. The estimated present value of this alternative is approximately $1.9 million.

WTL-5: Deep (3 feet) Excavation and Off-site Disposal, Backfill, and Wetland Restoration

Alternative WTL-5 includes excavation to remove all wetland sediment/soil with contaminants
in excess of the cleanup levels, estimated to be approximately 63,000 square foot area, and off-
site disposal of excavated sediment/soil. Pre-design investigation sampling results and
confirmatory sampling will refine and determine extent of excavation. Dewatering and
appropriate treatment of the extracted groundwater and any water removed from dewatering
saturated soils will be required in association with excavations below the groundwater table.
Treated water will be discharged to the Abeijona River or to appropriate off-site, licensed
disposal facility. The excavation area would be backfilled to pre-remediation grades and the
wetland habitat restored using native species. An estimated total of approximately 7,000 cubic
yards of material would be excavated. Plantings and visible ground surfaces will be inspected
and maintained until plantings are established. The time to achieve RAOs is estimated to be on
the order of 16 weeks. The estimated present value of this alternative is approximately $2.2
million.

2. Management of Migration Alternatives Analyzed

Management of migration (MM) alternatives address contaminants that have migrated into and
with the groundwater from the original source of contamination. At the SWP, contaminants have
migrated from surface and subsurface releases at the Whitney, Murphy and Aberjona Properties
into the site-wide groundwater. The MM alternatives for groundwater analyzed for the Site
include:

• GW-1: No Action

• GW-2: Institutional Controls

• GW-3: Monitored Natural Attenuation and Institutional Controls

• GW-4: In-Situ Bioremediation and Institutional Controls

• GW-5: In-Situ Chemical Oxidation (ISCO) and Institutional Controls

• GW-6: Pump and Treat and Institutional Controls

Each of the six MM alternatives is summarized below. A more complete, detailed presentation
of each alternative are found in the 2017 FS Report Addendum - Technical Report and Section 5
of the FS.

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Groundwater Alternatives

The groundwater alternative would be coordinated with the selected soil and NAPL cleanup
approach as excavation below the water table in the Northern Whitney Soil Area and NAPL
areas presents an opportunity for shallow groundwater treatment to be enhanced through the
placement of amended backfill. The amended backfill would treat shallow groundwater where
the amendment is placed.

GW-1: No Action

Alternative GW-1 is the No Action Alternative. This alternative provides no active groundwater
treatment. As required by CERCLA, five-year reviews would still be performed as part of the No
Action Alternative. As required by CERCLA and the NCP, the No Action Alternative serves as
a baseline for comparing the effectiveness of other remedial alternatives to be developed for
groundwater. Concentrations of contaminants in groundwater are assumed to remain unchanged
from current concentrations. Except for the cost of five-year reviews, there is no cost estimated
as part of this alternative.

GW-2: Institutional Controls

Alternative GW-2 includes implementation of Institutional Controls to prohibit future use of
impacted groundwater as a drinking water source and to control the future vapor intrusion
pathway. However, groundwater contaminant discharge to the wetland area would continue.
Five-year reviews will be required since contamination will be left in place. The estimated
present value of this alternative is approximately $0.05 million.

GW-3: Monitored Natural Attenuation and Institutional Controls

Alternative GW-3 includes long-term annual groundwater monitoring to monitor the
groundwater concentrations and evaluate the concentration decreases due to natural attenuation
(biodegradation, volatilization, dispersion, dilution, etc). Mitigation may be required for any
alteration of 500-year floodplain and/or wetlands from the installation and maintenance of
monitoring wells. Well locations would need to be designed so as to not interfere with the
remedial infrastructure required for the soil, NAPL, and wetland components of the selected
remedy. This alternative also includes the implementation of Institutional Controls to prohibit
future use of impacted groundwater as a drinking water source until groundwater cleanup
standards are achieved and to control the future vapor intrusion pathway. However, groundwater
contaminant discharge to the wetland area would continue. Five-year reviews will be required
since contamination will be left in place. Time to achieve cleanup levels is estimated from
approximately 100 to 225 years. The estimated present value of this alternative is approximately
$1.5 million.

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GW-4: In Situ Bioremediation and Institutional Controls

Alternative GW-4 includes the injection of microbes or substrates into the aquifer to stimulate
the biological breakdown of organic compounds, resulting in the subsequent reduced solubility
of metals. These reductions would eventually achieve groundwater cleanup standards. This
alternative requires the installation of several hundred injection points/wells. Two injection
events are assumed, the second injection event occurring approximately two years after the initial
injection event. Monitoring would be performed to follow the progress of the treatment, and
additional injections would be performed if the treatment appears to be incomplete or additional
treatment is periodically necessary to maintain contaminant reductions within a timely manner.
Groundwater contaminant migration into the wetlands would be controlled immediately by siting
of wells so that all contaminated groundwater will be treated before it migrates into the wetlands.
Mitigation may be required for any alteration of 500-year floodplain and/or wetlands from the
installation, operation, and maintenance of injection/monitoring wells. Well and injection
well/point locations would need to be designed so as to not interfere with the remedial
infrastructure required for the soil, NAPL, and wetland components of the selected remedy. This
alternative also includes the implementation of Institutional Controls to prohibit future use of
impacted groundwater as a drinking water source until groundwater cleanup levels are achieved,
and to control the future vapor intrusion pathway. Time to achieve cleanup levels is uncertain
due to difficulties with technology at greater depths, etc., but estimated to be approximately as
much as 94 years. Five-year reviews will be required since contamination will be left in place.
The estimated present value of this alternative is approximately $7.1 million.

GW-5: In Situ Chemical Oxidation (ISCO) and Institutional Controls

Alternative GW-5 includes the injection of oxidants into the aquifer to break down VOCs,
resulting in the subsequent reduced solubility of metals, PCBs and other typically low solubility
compounds. These reductions would eventually achieve groundwater cleanup standards.
However, the chemicals injected into the aquifer are associated with health hazards and require
extreme caution with management and application on the SWP. This alternative requires the
installation of several hundred injection points/wells. Three injection events are assumed for the
overburden with four injections assumed for bedrock. Monitoring would be performed to follow
the progress of the treatment, and additional treatment would be performed if the treatment
appears to be incomplete or additional treatment is periodically necessary to maintain
contaminant levels below cleanup standards. Groundwater contaminant migration into the
wetlands would be controlled immediately by siting of wells so that all contaminated
groundwater will be treated before it migrates into the wetlands. Mitigation may be required for
any alteration of 500-year floodplain and/or wetlands from the installation, operation, and
maintenance of injection/monitoring wells. Well and injection well/point locations would need
to be designed so as to not interfere with the remedial infrastructure required for the soil, NAPL,
and wetland components of the selected remedy. This alternative also includes the
implementation of Institutional Controls to prohibit future use of impacted groundwater as a
drinking water source until groundwater cleanup levels are achieved, and to control the future

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vapor intrusion pathway. Time to achieve cleanup levels is uncertain due to difficulties with
technology at greater depths, etc., but estimated to be approximately 92 years for the shallow and
intermediate zones. Five-year reviews will be required since contamination will be left in place.
The estimated present value of this alternative is approximately $27 million.

GW-6: Pump and Treat and Institutional Controls

Alternative GW-6 includes the installation and operation of a SWP-wide groundwater extraction
and treatment system to reduce contaminant concentrations in groundwater and provide
hydraulic containment, preventing further contaminant migration. The treatment system may
include components such as bag filters, activated carbon vessels, metals polishing vessels, air
strippers, vapor phase activated carbon, etc. Eighteen to twenty-two groundwater extraction
wells would be installed in the overburden and bedrock. Pre-design investigation activities will
include consideration of the age and upgrades to the adjacent Wildwood Source Area Property
groundwater treatment system plant to accommodate and adequately treat extracted groundwater
from the SWP in lieu of constructing a groundwater treatment plant on the SWP (while
continuing to treat extracted water from the Wildwood Source Area Property). Operation and
maintenance would include monitoring to assure that the extraction pumps are operating
properly, the treatment components are in proper operation, the activated carbon and ion
exchange resins are changed as needed, the air stripper is maintained, and compliance
monitoring for air emissions and treated water are being performed. Groundwater contaminant
migration into the wetlands would be controlled immediately by siting of wells so that all
contaminated groundwater will be removed and treated before it migrates into the wetlands.
Mitigation may be required for any alteration of 500-year floodplain and/or wetlands from the
installation, operation, and maintenance of the groundwater treatment system. Well and piping
locations, as well as the location of the treatment system, would need to be designed so as to not
interfere with the remedial infrastructure required for the soil, NAPL, and wetland components
of the selected remedy. This alternative also includes the implementation of Institutional
Controls to prohibit future use of impacted groundwater as a drinking water source until
groundwater cleanup levels are achieved, and to control the future vapor intrusion pathway.

Time to achieve cleanup levels is estimated to be approximately 20 years. Five-year reviews will
be required since contamination will be left in place. The estimated present value of this
alternative is approximately $4.2 million.

K. SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES

Section 121(b)(1) of CERCLA presents several factors that at a minimum EPA is required to
consider in its assessment of alternatives. Building upon these specific statutory mandates, the
NCP articulates nine evaluation criteria to be used in assessing the individual remedial
alternatives.

A detailed analysis was performed on the alternatives using the nine evaluation criteria in order
to select a remedy for the SWP. The following is a summary of the comparison of each

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alternative's strength and weakness with respect to the nine evaluation criteria. These criteria are
summarized as follows:

Threshold Criteria

The two threshold criteria described below must be met in order for the alternatives to be eligible
for selection in accordance with the NCP:

1.	Overall protection of human health and the environment addresses whether or not a
remedy provides adequate protection and describes how risks posed through each
pathway are eliminated, reduced or controlled through treatment, disposal, engineering
controls, or Institutional Controls.

2.	Compliance with applicable or relevant and appropriate requirements (ARARs)

addresses whether or not a remedy will meet all standards, requirements, criteria or
limitations under any Federal environmental law and all standards, requirements, criteria
or limitations under any more stringent State environmental or facility siting law, unless a
waiver is invoked.

Primary Balancing Criteria

The following five criteria are utilized to compare and evaluate the elements of one alternative to
another that meet the threshold criteria:

3.	Long-term effectiveness and permanence addresses the criteria that are utilized to
assess alternatives for the long-term effectiveness and permanence they afford, along
with the degree of certainty that they will prove successful.

4.	Reduction of toxicity, mobility, or volume through treatment addresses the degree to
which alternatives employ recycling or treatment that reduces toxicity, mobility, or
volume, including how treatment is used to address the principal threats posed by the site.

5.	Short term effectiveness addresses the period of time needed to achieve protection and
any adverse impacts on human health and the environment that may be posed during the
construction and implementation period, until cleanup goals are achieved.

6.	Implementability addresses the technical and administrative feasibility of a remedy,
including the availability of materials and services needed to implement a particular
option.

7.	Cost includes estimated capital and Operation and Maintenance (O&M) costs, as well as
present-worth costs.

Modifying Criteria

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The modifying criteria are used as the final evaluation of remedial alternatives, generally after
EPA has received public comment on the 2017 FS Report Addendum - Technical Memorandum,
RI/FS Report, and Proposed Plan:

8.	State acceptance addresses the State's position and key concerns related to the preferred
alternative and other alternatives, and the State's comments on ARARs or the proposed
use of waivers.

9.	Community acceptance addresses the public's general response to the alternatives
described in the Proposed Plan, 2017 FS Report Addendum - Technical Memorandum,
and RI/FS report.

Following the detailed analysis of each individual alternative, a comparative analysis, focusing
on the relative performance of each alternative against the nine criteria, was conducted. This
comparative analysis for soil (Whitney, Murphy and Aberjona Properties), groundwater, NAPL
and wetland sediment/soil can be found in Tables 6-1 through 6-6 of the FS, respectively, as
amended through discussions presented in the 2017 FS Report Addendum - Technical
Memorandum. Table 6-7 of the 2017 FS Report Addendum - Technical Memorandum, which
presents a summary of the comparative analysis, is attached to this ROD as Table K-l (see
Appendix B).

The section below presents the nine criteria and a brief narrative summary of the alternatives and
the strengths and weaknesses according to the detailed and comparative analysis.

Soil:

Overall Protection of Human Health and the Environment

All alternatives except for the No Action Alternative (SW-l/SM-l/SA-1) are protective of
human health and the environment. All of the alternatives other than the No Action Alternative
provide for Institutional Controls to prevent future residential, school, or daycare development of
the properties (except for the Existing Aberjona Residence area on the Aberjona Property) and to
protect against the future vapor intrusion pathway, with additional Institutional Controls needed
for the alternatives where there are components of the remedy the require protection (such as a
soil cap). Alternatives SW-2/SM-2/SA-2 provide an impermeable cap above the soils to prevent
exposure and prevent leaching of soil contaminants to groundwater, but do not provide for
excavation of significantly contaminated soil in the saturated zone at the Northern Whitney Soil
Area that could continue to impact groundwater and prolong the time to achieve groundwater
cleanup levels in the area. In addition, Alternatives SW-2/SM-2/SA-2 would result in flood
storage loss that requires mitigation measures within the watershed upstream of any sensitive
flood receptors to address any impairment within the 500-year floodplain. The ability of the
alternatives to be protective depends on the availability of suitable floodplain mitigation areas.
Alternatives SW-3/SM-3/SA-3 provide for the excavation and off-site disposal of the

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significantly contaminated soils (e.g., Northern Whitney Soil Area) and blending contaminated
soil below the water table with a treatment amendment prior to backfilling which would decrease
soil, groundwater and wetland impacts and provide an impermeable cap above the remaining
soils above cleanup levels to prevent exposure and leaching of soil contaminants to groundwater
which would reduce time to achieve groundwater cleanup levels. Alternatives SW-3/SM-3/SA-3
may use existing building foundations as part of the protective cap, if they are suitable. Caps
constructed under Alternatives SW-2/SM-2/SA-2 and SW-3/SM-3/SA-3 within the 500-year
floodplain need to be constructed and maintained to prevent any release of contamination during
flooding. Alternatives SW-4/SM-4/SA-4 provide for the excavation and off-site disposal of all
soils above cleanup levels located above the water table, along with excavation of the Northern
Whitney Soil Area. Alternatives SW-3/SM-3/SA-3 and Alternatives SW-4/SM-4/SA-4 each will
include potential treatment of water generated from excavations or dewatered soils and discharge
of treated water to the Aberjona River. All of the alternatives will require five-year reviews
since each will leave contaminated soil in place that exceeds unrestricted use risk standards.

Compliance with ARARs

All alternatives, except for the No Action and SW-2/SM-2/SA-2 Alternatives, have been
developed to comply with ARARs. The SW-2/SM-2/SA-2 Alternatives will not comply with
federal and state floodplain ARARs unless flood storage mitigation is possible within the
watershed upstream of any sensitive floodplain receptors. This is required to compensate for
floodplain storage capacity lost from the construction of the alternatives' soil caps above the
current grade of the floodplain. The impermeable caps constructed as part of the SW-3/SM-
3/SA-3 Alternatives will be constructed at grade so there is no loss of flood storage capacity, in
compliance with floodplain ARAR standards. This will be done by partially excavating the soil
within the floodplain to account for the caps' thickness. The design of the impermeable cap will
comply with TSCA and RCRA ARAR requirements pertaining to capping PCBs and/or
hazardous waste. Alternatives SW-4/SM-4/SA-4 meet ARARs as soils with concentrations
above cleanup levels located above the water table will be removed and will be managed on-site
in compliance with ARARs until disposed of at a licensed off-site disposal facility. Water and
any associated air discharges generated from dewatering activities during excavations and the
management of excavated soil will meet applicable ARAR discharge requirements. Alternatives
SW-3/SM-3/SA-3 will not result in net filling of the floodplain and will not cause any net flood
storage loss. Alternatives SW-3/SM-3/SA-3 and SW-4/SM-4/SA-4 will dispose of soils off-site
at a licensed facility and comply with TSCA and RCRA ARAR requirements.

Long-Term Effectiveness and Permanence

The No Action Alternatives rate the lowest for long-term effectiveness and permanence because
the risks identified in the baseline HHRA are not addressed and soil contaminants leaching to
groundwater above cleanup levels remain unchanged. The long-term effectiveness and
permanence of the capping and excavation (SW-3/SM-3/SA-3) and excavation only (SW-4/SM-
4/SA-4) alternatives are anticipated to be high, where SW-4/SM-4/SA-4 provides for the most
removal of contaminated soil. Although capping alone meets the criterion for long-term
effectiveness and permanence, a larger amount of significantly contaminated soils in the
unsaturated and saturated soil (e.g., the Northern Whitney Soil Area) will be left in place in

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Alternatives SW-2/SM-2/SA-2.

Reduction of Contaminant Toxicity, Mobility, or Volume through Treatment
Alternatives SW-l/SM-l/SA-1 and SW-2/SM-2/SA-2 do not include any treatment. Alternatives
SW-3/SM-3/SA-3 and SW-4/SM-4/SA-4 include very limited treatment as a component of each
alternative: significantly contaminated soils (e.g. Northern Whitney Soil Area) will be blended
with a treatment amendment to reduce soil and localized groundwater contamination (e.g.

VOCs), treatment of water generated from excavation/dewatering prior to disposal, and the
potential addition of bulking amendments to make excavated soils suitable for off-site disposal.

Short Term Effectiveness

The No Action Alternative will not be effective in the short-term in protecting human health or
the environment. Because no remedial activities will occur, ongoing short-term risks will still be
present. There would be no adverse short-term impacts to the public or workers because no
cleanup will be performed. The SW-2/SM-2/SA-2 and SW-3/SM-3/SA-3 Alternatives meet the
established RAOs for the soils, and will likely take approximately the same timeframe to achieve
RAOs. Although the SW-4/SM-4/SA-4 Alternatives will also achieve RAOs for soil, these
alternatives will take the longest time to implement due to the anticipated longer duration of site
work, causing more prolonged disruption to property owners and greater potential for accidents.

The community and workers performing the cleanup are protected the most in the short term by
Alternatives SW-2/SM-2/SA-2 because minimal soil disturbance is anticipated and no soils are
transported off-site (e.g. less truck traffic, etc.). Alternatives SW-3/SM-3/SA-3 will require
approximately 5,400 cubic yards of significantly contaminated soils to be transported off-site,
and an additional approximately 12,400 cubic yards of contaminated soil to be transported off-
site to prevent flood storage loss prior to cap placement (a total of approximately 18,000 cubic
yards). Alternatives SW-4/SM-4/SA-4 will also require approximately 5,400 cubic yards of
significantly contaminated soils, and an additional approximately 44,000 cubic yards of
contaminated soil, to be transported off-site (a total of approximately 49,000 cubic yards).
Alternatives SW-3/SM-3/SA-3 and SW-4/SM-4/SA-4 are the least protective of workers
performing the cleanup, as these alternatives involve the handling of large volumes of
significantly contaminated soil and the handling and treatment of water contaminated from the
remedial process. The SW-4/SM-4/SA-4 Alternatives would pose greater risks to workers and
the community compared to the SW-3/SM-3/SA-3 Alternatives since the SW-4/SM-4/SA-4
Alternatives involve a larger amount of excavation and volume of contaminated soils shipped off
site, a larger amount of contaminated water requiring treatment, a larger amount of fill delivered
on-site, and the most truck traffic. Air monitoring will need to be performed for worker and
community protection, and workers performing the cleanup will be required to wear appropriate
personal protective equipment.

Implementability

The No Action Alternative receives a high rating for implementability because no remedial
actions are required. Alternatives SW-2/SM-2/SA-2 may have significant implementability
issues because of the limited availability of areas for required floodplain mitigation. Regarding

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the active alternatives, capping and excavation remedial components are easy to implement due
to the availability of trained personnel, equipment and materials. Alternatives SW-3/SM-3/SA-3
are easier to implement and will be less disruptive to the existing on-property businesses
compared to SW-4/SM-4/SA-4 because it will require the complete or partial demolition of
fewer buildings (likely just on the Whitney Property) and the need to vacate the properties for
less time. Alternatives SW-3/SM-3/SA-3 will require construction of impermeable caps within
areas with active businesses and possible tie in of the caps into existing building foundations.

Cost

Except for the cost of five-year reviews, there is no cost estimated as part of the No Action
Alternatives. Of the active alternatives, Alternatives SW-2/SM-2/SA-2 have the lowest costs,
since no soil excavation/disposal is required. Building demolition, off-site transport and disposal
of contaminated soils, and volume of clean fill delivered are the most costly components of the
SW-3/SM-3/SA-3 and SW-4/SM-4/SA-4 Alternatives. The SW-4/SM-4/SA-4 Alternatives are
the most expensive alternatives, because of the larger volumes of soil to be excavated/disposed
of. See Table K-l in Appendix B for a summary of costs for all alternatives.

State and Community Acceptance

The State has expressed its support for Alternative SW-3/SM-3/SA-3. The State does not
believe that Alternative SW-l/SM-l/SA-1 provides adequate protection of human health and the
environment. The State does not support SW-2/SM-2/SA-2 because it does not use treatment as
a permanent solution.

During the public comment period, members of the community expressed support for either
Alternatives SW-3/SM-3/SA-3 or SW-4/SM-4/SA-4. Alternatives SW-l/SM-l/SA-1 and SW-
2/SM-2/SA-2 were not considered adequately protective.

NAPL:

Overall Protection of Human Health and the Environment

Alternative N-l does not eliminate the NAPL source material nor prevent its movement;
therefore, the N-l Alternative is not protective of human health or the environment. The N-2 and
N-3 Alternatives protect human health and the environment by reducing or eliminating a
continuing NAPL source of contamination to soil, groundwater and the wetlands. The N-3
Alternative will more effectively and quickly eliminate the NAPL through excavation, while the
N-2 Alternative will rely on slow removal of the NAPL by skimming and controlling movement
to the wetland. The N-2 Alternative, which uses skimming and movement control technologies,
may not be completely effective at recovering NAPL and/or preventing NAPL discharge to the
wetland. The N-2 Alternative also includes Institutional Controls to prevent human contact with
the NAPL until its removal is complete. The N-3 Alternative is more protective of human health
and the environment than the N-2 Alternative, since a larger volume of NAPL will be removed
over less time resulting in a lower risk of discharge to the wetlands and faster groundwater
remediation. As part of the N-3 Alternative the addition of amendments such as ZVI to address
any remnant NAPL contamination in the subsurface soil prior to backfilling the excavation work
further increases the protectiveness of the alternative.

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Compliance with ARARs

There are no chemical-specific ARARs for NAPL. However, the N-l Alternative will not meet
risk-based standards developed using chemical-specific TBCs since no removal or containment
of NAPL will occur. Alternatives N-2 and N-3 can be implemented in compliance with location
and action-specific ARARs, in particular, State standards that require all NAPL be removed to
the extent practicable. Alternative N-3 achieves risk-based standards developed using chemical-
specific TBCs because removal of the NAPL through excavation will prevent its continuing
discharge to the wetland and will eliminate it as a continuing source of contamination to soil and
groundwater, facilitating the cleanup of those media. It is less certain that the N-2 Alternative
will achieve risk-based standards developed using chemical-specific TBCs, and more time may
be required to remove the NAPL from the subsurface and eliminate the NAPL movement.
Alternatives N-2 and N-3 do not result in net filling of the 500-year floodplain and will not cause
any net flood storage loss. Water and air discharges generated from dewatering activities during
excavation and the management of excavated soil under Alternative N-2 (during trench
installation) and during the excavation work under Alternative N-3 will meet applicable ARAR
discharge requirements.

Long-Term Effectiveness and Permanence

The N-l Alternative has no long-term effectiveness or permanence due to lack of NAPL
removal. Alternative N-3 is expected to have the best long-term effectiveness and permanence
because the NAPL will be excavated and disposed off-site. This process is permanent, reliable,
and certain to reduce risks. The N-2 Alternative is expected to have less long-term effectiveness
than Alternative N-3 since residual NAPL may remain.

Reduction of Contaminant Toxicity, Mobility, or Volume through Treatment
N-l Alternative would provide no reduction in toxicity, mobility and volume of NAPL through
treatment. Alternative N-2 may have some very limited treatment through the required treatment
of water generated during the installation of the trench. Alternative N-3 also includes very
limited treatment of a potentially larger volume of contaminated water generated both from the
excavation and from dewatering any saturated excavated soil. Treatment will achieve both water
and air discharge standards. There may also be some reduction of pollutant mobility through the
addition of bulking agents to allow for off-site disposal of the excavated material.

Short Term Effectiveness

The No Action Alternative will not be effective in the short-term in protecting human health or
the environment, but because no remedial activities will occur, there will be no adverse impacts
to the public or workers performing the cleanup. Although Alternative N-2 involves very little
short term risk to workers, NAPL is brought to the surface where it would need to be
appropriately managed for an extended period of time. The N-3 Alternative will achieve RAOs
in the shortest period of time since NAPL will be excavated and no longer serve as a source of
impacts to soil, groundwater, and the wetland. However, Alternative N-3 may be associated with
short-term risks to workers performing the cleanup due to the required handling of NAPL-
impacted materials and more disruption to property owners. Air monitoring will need to be

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performed for worker and community protection, and workers performing the cleanup will be
required to wear appropriate personal protective equipment.

Implementability

Alternative N-l is the easiest to implement because it does not involve excavation and off-site
disposal or the construction, operation, or maintenance of a remedial system or enforcement of
Institutional Controls. The N-2 Alternative is more difficult to implement than the N-3
Alternative because it requires the construction, operation or maintenance of a remedial system
{i.e. collection wells and trench) to recover NAPL in the subsurface. The trench and collection
well system would also need to be installed and maintained so that it doesn't interfere with any
of the caps to be installed as part of the soil component of the remedy. In addition, Alternative N-
2 may be less reliable for eliminating the subsurface NAPL and may require the use of additional
remedial technologies in the future to achieve RAOs. The reliability of the N-3 Alternative is
high because excavation and off-site disposal are relatively routine tasks. However, it produces
the highest amount of disruption to property owners and greater impact to the community from
increased truck traffic during its brief implementation duration. Excavation work needs to be
coordinated with the other components of the remedy: soil excavation/capping, sediment
excavation, and the groundwater pump and treat system.

Cost

Except for the cost of five-year reviews, there is no cost estimated as part the N-l Alternative.
Alternative N-3 costs are more than four times that of the N-2 Alternative. See Table K-l in
Appendix B for a summary of costs for all alternatives.

State and Community Acceptance

The State has expressed its support for Alternative N-3. The State does not believe that
Alternative N-l provides adequate protection of human health and the environment. The State
does not support N-2 because it may not be effective in removing all NAPL from the subsurface.

During the public comment period, members of the community expressed support for Alternative
N-3. Alternatives N-l and N-2 were not considered adequately protective.

Wetland Sediment/Soil:

Overall Protection of Human Health and the Environment

All alternatives except for the WTL-1 Alternative and WTL-2 Alternative are protective of
human health and the environment. Alternative WTL-2 is not protective of the environment
because conditions do not appear to be suitable for natural recovery, although Institutional
Controls to prevent access to the wetland would be in place for the protection of human health.
The alternative does not include measures to protect the environment. Alternative WTL-3
provides a cap above the wetland sediments/soils to prevent human and environmental
exposures, but does not provide for excavation of wetland sediment/soil. Therefore, it will
require wetland and flood storage mitigation elsewhere nearby within the watershed. Alternative
WTL-4 provides for the excavation and off-site disposal of the high concentration wetland

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sediments/soils, and provides a cap above the remaining lower concentration wetland
sediments/soils to prevent exposure. The excavation of wetland sediments/soils and restoration
of the wetland to initial grades would prevent the need for further wetland or flood storage
mitigation (other than restoring the surface of the cap to native wetland/aquatic habitat and
restoring any access ways to the excavation/cap areas). Alternatives WTL-3 and WTL-4 also
provide for Institutional Controls to prevent disturbance of the cap and long-term monitoring to
confirm that cleanup levels continue to be met over time. Alternative WTL-5 provides for the
excavation and off-site disposal of wetland sediments/soils above cleanup levels, restoration of
the wetland to initial grades to prevent the need for further wetland or flood storage mitigation
measures, and no institutional controls. Therefore, WTL-5 is most protective of human health
and the environment.

Compliance with ARARs

All alternatives except for the WTL-1 and WTL-2 Alternatives will comply with ARARs. Under
Alternative WTL-1 PCB-impacted wetland sediment/soil will not be removed or treated so will
not comply with chemical-specific ARARs for PCBs and metals. Alternative WTL-2 is not
expected to meet chemical-specific ARARs for PCBs and metals within a reasonable period of
time since MNR is not effective for PCBs and metals. The WTL-3 Alternative does not include
adequate provisions to comply with ARARs requiring wetland and flood storage mitigation
within the watershed to replace wetland/floodplain filled to install the cap. The WTL-4 and
WTL-5 Alternatives will comply with federal and state waste disposal regulations since wetland
sediment/soil with PCBs exceeding TSCA thresholds will be excavated and disposed off-site,
rather than capped on-site. WTL-4 and WTL-5 Alternatives will also reestablish the wetlands in
place so that wetland mitigation may occur in place. Alternatives WTL-4 and WTL-5 do not
result in net filling of the 500-year floodplain and will not cause any net flood storage loss.
ARAR standards also require that caps need to be designed and maintained so as to not result in
any contaminant releases in up to a 500-year storm event. Water and air discharges generated
from dewatering activities during excavation and the management of excavated sediment/soil
under Alternatives WTL-4 and WTL-5 will meet applicable ARAR discharge requirements. All
work within the wetlands under Alternatives WTL-3, WTL-4, and WTL-5 will meet Action-
specific standards for protecting water quality. Excavated sediments/soils generated from
Alternatives WTL-4 and WTL-5 will be managed on-site in compliance with ARARs until
disposed of at a licensed off-site disposal facility. WTL-5 Alternative removes all wetland
sediments/soils above action levels and does not require Five Year Reviews because no waste
will be left in place. EPA has determined that Alternative WTL-5 is the LEDPA under the
federal Clean Water Act for addressing contaminants in the wetland, while protecting wetland
resources.

Long-Term Effectiveness and Permanence

The WTL-1 and WTL-2 Alternatives would be neither effective in the long-term nor provide
permanent protection from contaminated sediment/soil because contaminant concentrations
exceeding cleanup levels will remain and exposure pathways to these contaminants continue to
exist, indicating a high level of residual risk remains. The long-term effectiveness and
permanence of the WTL-5 Alternative is the highest. With Alternative WTL-5, all contaminated

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wetland sediments/soils would be removed, backfilled with clean wetland soil, and restored to
original grades. Although capping meets the criterion for long-term effectiveness and
permanence, a large amount of significantly contaminated wetland sediment/soil will remain in
place in Alternative WTL-3. The significantly contaminated wetland sediments/soils are
removed in Alternative WTL-4, but this alternative, like the WTL-3 Alternative, relies on cap
integrity to maintain protectiveness. Long-term effectiveness is dependent on durability of the
cap.

Reduction of Contaminant Toxicity, Mobility, or Volume through Treatment
The WTL-1, WTL-2, WTL-3, and WTL-4 Alternatives do not include any treatment so do not
meet the criterion. Alternatives WTL-4 and WTL-5 include limited treatment of any water
generated from the excavation or from dewatering sediments/soils prior to discharge and any
bulking agents used to reduce contaminant mobility prior to off-site disposal.

Short Term Effectiveness

The WTL-1 Alternative will not be effective in the short-term in protecting human health or the
environment, but because no remedial activities will occur, there will be no adverse impacts to
the public or workers performing the cleanup. Alternative WTL-2 will have limited
effectiveness in preventing human contact once Institutional Controls are established. The
WTL-3 Alternative ranks the lowest for short term effectiveness due to the deleterious effects the
filling of the wetland will have on wetland species. The WTL-3 Alternative will also require the
longest time to achieve RAOs due to the need to construct a compensatory wetland elsewhere
nearby within the watershed, prior to capping the wetland, and the time required for
establishment of the replacement wetland.

Alternatives WTL-4 and WTL-5 rank intermediate for short term effectiveness. Because these
alternatives include the excavation and handling of significantly contaminated wetland
sediment/soil, air monitoring will need to be performed for worker and community protection,
and workers performing the cleanup will be required to wear appropriate personal protective
equipment. In addition, there will be temporary adverse impacts to wetland species within the
work area.

Implementability

All five alternatives rank highly for implementability, except for Alternative WTL-3 where the
feasibility of constructing compensatory wetland/flood storage elsewhere nearby within the
watershed will be difficult/uncertain. Alternative WTL-1 is the easiest to implement because no
remedial action will be taken. Alternative WTL-2 will also be easy to implement since long-term
monitoring requires few resources and can be easily implemented. For Alternatives WTL-3,
WTL-4 and WTL-5, there are no technical barriers associated with capping, excavation or
institutional controls. The necessary trained personnel, equipment and materials are readily
available to implement each alternative.

Cost

The range in estimated cost for all five alternatives is from $0 million for WTL-1 (No Action)

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(except the cost of five-year reviews) to $2.2 million for Alternative WTL-5. The WTL-5
Alternative is the most costly alternative and is moderately more costly than the WTL-3 ($1.0
million) and WTL-4 ($1.9 million) Alternatives. See Table K-l in Appendix B for a summary
of costs for all alternatives.

State and Community Acceptance

The State has expressed support for Alternative WTL-5. The State does not believe that
Alternative WTL-1 provides adequate protection of human health and the environment. The
State does not support Alternative WTL-2 and WTL-3 because they do not use treatment as a
permanent solution.

During the public comment period, members of the community expressed support for either
Alternatives WTL-4 or WTL-5. Alternatives WTL-1, WTL-3 and WTL-3 were not considered
adequately protective.

Groundwater:

Overall Protection of Human Health and the Environment

The protectiveness of all the groundwater alternatives, except the GW-1 No Action Alternative,
is in part contingent on the effectiveness of the source control alternatives for NAPL, soil, and
the wetlands. Alternative GW-1 (No Action Alternative) fails this criterion because it does not
address risks posed by contaminated groundwater. Alternative GW-2 (Institutional Controls)
fails the overall protection of human health and the environment criterion because, although it
would address human contact risks, it will not reduce, control or eliminate risks to human health
or the environment. Alternative GW-3 does not meet this criterion because relying on monitored
natural attenuation to achieve cleanup standards will not achieve cleanup standards within a
reasonable time period (100-225 years) compared with active remedial alternatives. The GW-4
and GW-5 Alternatives pass this criterion, but the distribution and performance challenges of
groundwater cleanup at greater depths may prevent the injection alternatives from effectively
achieving groundwater cleanup standards. The GW-6 Alternative passes the overall protection of
human health and the environment. The alternative protects human health by prohibiting use of
contaminated groundwater as a drinking water source via Institutional Controls until cleanup
levels are met in approximately 20 years. GW-3 through GW-6 all will include measures to
prevent migration of contaminated groundwater into the adjacent wetlands. The time to achieve
cleanup levels for Alternatives GW-3 through GW-6, ranked from the longest to shortest time
frames are GW-3 (approximately 100 to 225 years), GW-4 (approximately 94 years), GW-5
(approximately 92 years) and GW-6 (approximately 20 years). The GW-6 Alternative also
provides for hydraulic containment of groundwater contaminants, limiting movement of
contamination that poses a risk to the adjacent wetlands.

Compliance with ARARs

The No Action Alternative fails because it contains no remedial action to address ARAR
requirements to restore the groundwater. Alternative GW-2 fails the compliance with ARARs
criterion because it includes no provision to restore groundwater to required ARAR-based

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cleanup levels. Alternative GW-3 does not pass this criterion because the estimated time to
achieve cleanup levels does not meet TBC standards for Monitored Natural Attenuation remedies
to meet groundwater cleanup standards within a reasonable time period, compared to active
treatment alternatives (100 to 225 years compared to 20 years for the pump and treat alternative).
Alternatives GW-4, GW-5 and GW-6 will meet chemical-specific ARARs because of treatment
of groundwater contamination throughout the overburden and bedrock, although there is less
certainty about the effectiveness in the two injection alternatives fully meeting groundwater
cleanup standards. Alternative GW-6 is expected to achieve ARAR-based groundwater cleanup
goals in the shortest timeframe (approximately 20 years). There are no location or action-
specific ARARs for Alternative GW-1. The GW-3, GW-4, GW-5, and GW-6 Alternatives all
will meet ARAR requirements for mitigation of any alteration of 500-year floodplain and/or
wetlands from the installation and maintenance of injection/monitoring wells or piping systems.
Alternative GW-6 also will meet all water and air treatment and discharge ARAR requirements
for the pump and treat system.

Long-Term Effectiveness and Permanence

The No Action Alternative is neither effective in the long term nor effective with respect to
permanence because it will have the highest residual risk due to lack of Institutional Controls or
groundwater treatment. Due to the need for permanent Institutional Controls for the GW-2
Alternative and that the alternative does not address ongoing migration of contamination to the
wetlands, this alternative is considered less effective in the long term than the remaining
alternatives. Alternative GW-3, which is expected to require over 100 years to achieve cleanup
levels, may require that institutional controls remain in place for an extended period of time,
which negatively impacts its long-term effectiveness. Also, it is not known whether natural
process alone will ultimately reduce groundwater contaminant levels to cleanup standards.
Alternatives GW-4, GW-5, and GW-6 are all expected to have good long-term effectiveness due
to the combination of Institutional Controls and active treatment. Rebounding concentrations
may occur with the GW-4 and GW-5 Alternatives along with the formation of undesirable
breakdown products and potentially temporary metals mobilization. While rebound may also
occur with Alternative GW-6, it can be addressed through operational changes to pumping while
maintaining containment of impacted groundwater. Treatment residuals formed as part of the
GW-6 Alternative can be properly managed and pose minimal risk.

Reduction of Contaminant Toxicity, Mobility, or Volume through Treatment
The No Action, GW-2, and GW-3 Alternatives do not meet this criterion because treatment is
not part of the alternatives. Alternative GW-6 scores the highest for this criterion for extracting
and treating contaminated groundwater. The GW-4 and GW-5 Alternatives scored intermediate
for this criterion. For the GW-4 Alternative, contaminant concentrations over the cleanup levels
will be treated, but residuals may remain. Toxic breakdown products (such as vinyl chloride)
may potentially form with the implementation of Alternative GW-4 and metals may be
temporarily mobilized by the treatment of groundwater associated with the GW-5 Alternative.

Short Term Effectiveness

The No Action and GW-2 Alternatives have no impact on human health and the environment as

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a result of implementation. The GW-3 Alternative may have some minor impact due to
monitoring well installation, sampling, and maintenance and relies on permanent Institutional
Controls. The short-term effectiveness of the GW-3 Alternative relies on long-term Institutional
Controls, while the GW-4, GW-5, and GW-6 Alternatives will prevent human exposure to
contaminants in groundwater through Institutional Controls, preventing use of groundwater as
drinking water until cleanup levels are achieved and active treatment. Alternative GW-6 is
predicted to achieve groundwater cleanup goals more quickly than the other alternatives.
Reagents used under the GW-4 Alternative would be of low toxicity while exposure to treatment
residuals associated with the GW-6 Alternative can be readily controlled. The GW-5 Alternative
is ranked the lowest in terms of short term effectiveness because the chemical oxidants are
reactive and require special handling, and migration of oxidants to the wetland area may pose a
concern.

Implementability

Alternative GW-1 is the easiest to implement because it does not involve the construction,
operation or maintenance of remedial systems or enforcement of Institutional Controls. The
GW-2 Alternative would also be easy to implement because it only requires the establishment
and enforcement of Institutional Controls. Alternative GW-3 would be easier to implement than
the GW-4, GW-5 or GW-6 because it would only involve installation, sampling, and
maintenance of monitoring wells, rather than active treatment infrastructure. Of the active
remedial alternatives considered for groundwater, Alternative GW-6, though it includes the
construction of a treatment plant and installation of transfer lines and extraction wells, is easier to
implement in the short term than the GW-4 and GW-5 Alternatives because these alternatives
require the installation of several hundred injection points/wells and effective reagent dispersal
with greater depths in overburden and in the bedrock is uncertain. The reliability of the GW-6
Alternative is high because groundwater extraction, treatment, and discharge are relatively
routine tasks and equipment and services required for implementation are readily available.
Alternatives GW-3, GW-4, GW-5, and GW-6 all have varying levels of implementability issues
with installing/maintaining monitoring/treatment wells and other groundwater infrastructure in
areas also subject to remedial measures being taken to address soils, NAPL, and wetland (e.g.
protecting impermeable caps).

Cost

The range in estimated cost for all six alternatives is from $0 million for GW-1 (No Action)
Alternative (except for the cost of five-year reviews) to $27 million for the GW-5 Alternative.
See Table 6 (alternative comparison table) for a summary of costs for all alternatives. Of the
active remedial alternatives considered for groundwater, Alternative GW-6 has the lowest cost
(approximately $4.2 million). See Table K-l in Appendix B for a summary of costs for all
alternatives.

State and Community Acceptance

The State has expressed support for Alternative GW-6. The State does not believe that
Alternative GW-1 provides adequate protection of human health and the environment. The State
does not support Alternatives GW-2 and GW-3 because they do not use treatment as a permanent

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solution.

During the public comment period, the members of the community expressed support for
Alternative GW-6. Alternatives GW-1 and 2 were not considered adequately protective.

L. I lll SELECTED REMEDY

1. Summary of the Rationale for the Selected Remedy

The selected remedy is a comprehensive remedy which utilizes source control and management
of migration components to address the principal SWP risks in soil (refers to Alternatives SW-3,
SM-3 and SA-3), groundwater (refers to selected Alternative GW-3) and wetland sediment/soil
(refers to selected Alternative WTL-5), as well as NAPL (refers to selected Alternative N-3)
which serves as a continuing source of contamination to groundwater as contaminants
leach/dissolve from the NAPL and migrate to groundwater. Source control measures are
required to address soil, NAPL, and wetland sediment/soil at the SWP that present unacceptable
risks to human health or to environmental receptors, exceed ARARs, or contribute to
exceedances of groundwater and/or soil ARAR and risk-based standards. The management of
migration component addresses contaminants in groundwater underlying the SWP that exceed
ARARs or otherwise pose an unacceptable risk. Of all the alternatives, the selected remedy best
satisfies the statutory criteria for remedy selection.

The major components of the remedy are as follows:

1.	Excavation and off-site disposal of approximately 5,400 cubic yards of significantly
contaminated soil at the designated Northern Whitney Soil Area (See Figure L-l
denoting "Excavation" and "Deeper Excavation"), and blending remaining contaminated
subsurface soil below the water table with an amendment (e.g., ZVI) prior to backfilling
to provide soil and localized groundwater treatment. In addition, excavation and off-site
disposal of approximately 12,400 cubic yards of soil in the Murphy upland, Whitney, and
Aberjona Property areas to facilitate installation of impermeable caps14 (for a total of
approximately 18,000 cubic yards of excavated soil). Installation of impermeable caps
over areas with lower concentration soils that exceed cleanup levels to reduce soil
exposure risks and/or prevent contaminant movement to groundwater (See Figure L-l
denoting "Cap Area");

2.	Excavation and off-site disposal of NAPL in the Murphy and Whitney Property areas,
including approximately 6,000 cubic yards of NAPL-contaminated soil and blending any
remaining NAPL-contaminated soil below the water table with an amendment (e.g., ZVI)
prior to backfilling to provide soil and localized groundwater treatment (See Figure L-2);

14 A cap is considered an impermeable barrier that meets applicable regulatory- (e.g., TSCA and/or RCRA) or risk-
based requirements, as appropriate, and mitigates contaminated soil risks by preventing direct contact, movement to
groundwater and erosion.

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3.	Containment and cleanup of groundwater contaminants throughout OU4 by pumping and
treating the groundwater (See Figure L-3);

4.	Excavation and off-site disposal of approximately 7,000 cubic yards of wetland
sediment/soil from the Murphy Wetland exceeding cleanup levels and wetland restoration
(See Figure L-4);

5.	Long-term monitoring and periodic Five-Year Reviews;

6.	Institutional Controls to maintain the integrity of the soil caps and other remedial
components; to prevent development of the properties for residential, school, and daycare
use; to prohibit use of contaminated groundwater until cleanup levels are met; and to
require evaluation of the vapor intrusion pathway if a change in usage of any of the
existing buildings is contemplated, or as part of new building construction, including any
addition to existing buildings on any of the properties. To facilitate future use and
redevelopment of the SWP consistent with the cleanup, Institutional Controls will be
established to preserve the remedy, and appropriately manage impacted soil and
groundwater encountered during future intrusive activities (e.g. installing subsurface
utilities, building foundations/slabs, etc.,) to protect human health and the environment;
and

7.	The remedy is estimated to cost approximately $19.1 million and is expected to take 1-2
years to construct. Groundwater is estimated to achieve cleanup standards in 20 years.

2. Description of Remedial Components

The selected remedy is consistent with EPA's preferred alternatives outlined in the July 2017

Proposed Plan.

Common components of the Remedy for all media throughout the SWP are:

Institutional Controls

In order to protect human health by controlling potential exposures to contaminated soils, NAPL
and groundwater, the selected remedy relies on the use of Institutional Controls including
limitations on land and groundwater uses and activities. Institutional Controls are also necessary
for the protection of the selected remedy, including limitations on uses and activities that
interfere with or disturb components of the remedy. Institutional Controls will be required to
prevent residential, school, and daycare uses of the current industrial/commercial portions of the
Whitney, Murphy and Abeijona Properties. Institutional controls will also be necessary to: (a)
prohibit use of impacted groundwater until cleanup levels are achieved; (b) maintain the integrity
of the caps and other remedial infrastructure; and (c) require the evaluation of the vapor intrusion
pathway if a change in building usage of any of the existing buildings is contemplated or as part
of new building construction, including any addition/alteration to existing buildings on any of the
properties. Should someone wish to demonstrate that there are no unacceptable risks from vapor
intrusion and therefore mitigation systems are not required, an evaluation of vapor intrusion risks
(following EPA-approved procedures and subject to EPA approval) may be performed prior to a

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change in building usage or the building of structures above the VOC plume to demonstrate that
vapor intrusion risks are within or below EPA's target risk levels (risk range of 10"4 to 10"6 and/or
a target organ HI of 1). To facilitate future use and redevelopment of the SWP consistent with
the cleanup, Institutional Controls will be established to preserve the remedy, and appropriately
manage impacted soil and groundwater encountered during future intrusive activities (e.g.
installing subsurface utilities, building foundations/slabs, etc.) to protect human health and the
environment. The details of the Institutional Controls will be resolved during the pre-design and
remedial design phase in coordination with the parties performing the Remedial Action,
impacted landowners, local officials, and MassDEP. Institutional Controls may be implemented
through measures that may include, but are not limited to, a local Town ordinance, a Notice of
Activity and Use Limitation (NAUL), or a Grant of Environmental Restriction and Easement
(GERE)15.

Under TSCA regulatory standards at 40 C.F.R. §761.61(c), the Region has made a determination
that addressing remnant PCBs that exceed unrestricted use levels but don't exceed recreational
exposure levels through Institutional Control restrictions on residential, school, and daycare use
of the SWP properties (except for the Aberjona residential area), as well as drinking water
restrictions until PCB groundwater cleanup standards are achieved, as set out in this Record of
Decision, will not pose an unreasonable risk of injury to health or the environment. See TSCA
Determination included as Appendix E to this ROD.

Five-Year Reviews

At the conclusion of remedy construction, hazardous substances, pollutants or contaminants will
remain at the SWP, as is also the case at other Operable Units within the Wells G&H Site.
Therefore, as required by law, EPA will review the SWP remedy to assure that the remedial
action continues to protect human health and the environment at least once every five years as
part of the Agency's five-year reviews for the entire Site16. These five-year reviews will
evaluate the components of the remedy for as long as contaminated media above CERCLA risk
levels remain in place. The purpose of the five-year review is to evaluate the implementation and
performance of the remedy in order to determine if the remedy is or will be protective of human
health and the environment. The five-year review will document recommendations and follow-
up actions as necessary to ensure long-term protectiveness of the remedy or bring about
protectiveness of a remedy that is not protective. These recommendations could include
providing additional response actions, improving O&M activities, optimizing the remedy,
enforcing access controls and Institutional Controls, and conducting additional studies and
investigations.

Components of the remedy specific to the soil NAPL. groundwater, and wetland sediment/soil

15NAULs and GEREs are approved forms of Massachusetts land use restrictions established under the MCP.

16 The next five-year review for the Site (the fifth) is due in September 2019. The start of five year reviews was
triggered by the initiation of the ground water pump and treat remedies in OU1.

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remediation are:

Soil Remediation

The selected remedy component for SWP soil, Excavation, Off-Site Disposal, Capping, and
Institutional Controls, includes the following components:

•	Pre-design investigations to further define the horizontal and vertical extents of soil
contamination, including the extent of PCBs greater than or equal to 50 mg/kg;

•	Pre-design investigations to understand the structural integrity of the Whitney Building,
and, as necessary, any other buildings and the potential presence of hazardous building
materials for abatement/management;

•	Bench-scale testing of soil amendments (e.g. ZVI) for backfill to treat and mitigate
localized soil and groundwater contamination (with emphasis on reducing chlorinated
VOCs);

•	Sequencing Plan for implementing the soil remedy in a manner that minimizes
disruptions to on-going business operations, to the extent practical, including determining
whether existing business on the properties will need to be relocated;

•	Design, site preparation and building demolition, as required;

•	Installing any wetland/floodplain mitigation measures that may be required, establishing
stormwater/erosion control measures, clearing and grubbing of excavation areas,
relocating utilities to implement excavation, installing temporary roads to support
excavation, and land surveying all clean-up infrastructure to be left in place (e.g.,
impermeable caps, monitoring wells);

•	Installation of shoring around the perimeter of excavations, as required. The shoring may
be necessary to prevent collapse of the excavation sidewalls, impacts to the nearby
wetlands/floodplain, and damage to nearby structures;

•	Excavate approximately 5,400 cubic yards of significantly contaminated soil at the
Northern Whitney Soil Area17, as well as approximately 12,400 cubic yards of soil across
the SWP to facilitate capping18 while complying with federal and State ARARs,
including causing no net flood storage loss (for a total of approximately 18,000 cubic
yards of excavated soil). Perform confirmation sampling to demonstrate compliance with
excavation goals. Manage excavated soils on-site based on their level of contamination
and then dispose off-site at a licensed facility. Add amendments, such as Portland
cement, to the excavated soil to meet off-site disposal facility standards, if required. At

17	See Figure L-l denoting "Excavation" and "Deeper Excavation" areas.

18	See Figure L-l denoting "Cap Area".

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the Northern Whitney Soil Area, address any remaining contamination left at the bottom
of the excavations below the water table by blending a treatment amendment to reduce
VOCs and provide soil and localized groundwater treatment19. Backfill excavations with
amended soil below the water table and clean soil above the water table (leaving space to
install an impermeable cap at the original grade). Construct the impermeable cap across
the SWP where soils are above Cleanup Levels, conceptually including geomembranes,
geotextiles and 2 feet of imported material (e.g., common borrow, subbase and asphalt,
clean soil, etc.). Install the cap over remaining contaminated soils exceeding cleanup
criteria in the subsurface to prevent direct contact, movement to groundwater and erosion
(see Figure L-5). Restoring the SWP to original grades for no net flood storage loss;

•	Dewater the portion of the excavation that extends below the water table and any
excavated soils that require dewatering, treat the water through a temporary treatment
system and discharge the treated water to the Aberjona River (or appropriate off-site
disposal at permitted facility, or appropriate approved discharge to Publicly Owned
Treatment Works (POTW), or appropriate approved on-site treatment and discharge from
adjacent Operable Unit-1 source area property (Wildwood Source Area Property);

•	Air monitoring during the excavation/capping, as well as monitoring of the adjacent
wetlands/waterways, to ensure no contaminant releases impact human health and/or
environment during the cleanup activities, as required;

•	Implement a long-term inspection and maintenance plan to ensure impermeable cap
integrity, maintenance, and repair and to maintain any required wetland/floodplain
mitigation and/or stormwater controls or other remedial infrastructure; and

Long-term monitoring of environmental media to evaluate remedy effectiveness.

Figure L-l provides a conceptual layout of the soil remedy. Figure L-5 provides conceptual
fill/cap designs for the proposed impermeable caps associated with the Remedy. The Remedy on
the Whitney Property includes the demolition of all or part of the Whitney building (including
removal of any contaminated media (e.g. asbestos, etc.) prior to demolition), as required;
installation of shoring around the perimeter of the excavation to prevent collapse of the
excavation sidewalls and impacts to the nearby wetlands/floodplain; the excavation and off-site
disposal of approximately 5,400 cubic yards of significantly contaminated soils; and removal of
the existing drain line from the Whitney building floor drain to the Massachusetts Water
Resources Authority (MWRA) sewer manhole as indicated in Figure L-l (denoting
"Excavation" and "Deeper Excavation"). The Northern Whitney Soil Area denoted as
"Excavation" is expected to be excavated to groundwater table, which ranges approximately 6
feet to 10 feet below ground surface (approximate average depth of 8 feet below ground surface),
while the "Deeper Excavation" is estimated to be excavated below the groundwater level to 15

19 See Figure L-l denoting "Deeper Excavation" where amendment will be blended with soils within the shallow and
upper portion of the intermediate groundwater zone (e.g. blending estimated from bottom of excavation to 24 feet
below ground surface).

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feet below ground surface. Confirmation sampling will be performed to demonstrate compliance
with excavation goals. Soil at the bottom of the excavation below the water table will be blended
with an amendment to reduce VOCs and provide soil and localized groundwater treatment. The
Northern Whitney Soil Area denoted "Deeper Excavation" will be blended with an amendment
from the bottom of excavation (e.g., 15 feet below ground surface) to 24 feet below ground
surface. Excavations will be backfilled with blended soil amendment below the water table and
clean soil above the water table (leaving space to install the impermeable cap at grade).

Some of the excavation will extend below the water table (e.g., Figure L-l) denoted "Deeper
Excavation") and require dewatering. The area of soil excavation is expected to overlap in some
parts with the area of NAPL-contaminated material to be excavated. The dewatering water is
expected to be treated to appropriate levels prior to proper discharge into the Abeijona River (or
appropriate off-site disposal at permitted facility, or appropriate approved discharge to the
POTW, or appropriate approved on-site treatment and discharge from adjacent Operable Unit-1
source area property (Wildwood Source Area Property)). Treatment may include storage and
settling tanks, filtration (e.g., bags filters), air stripping to remove VOCs, activated carbon to
remove PCBs (as well as VOCs), and ion exchange resins to remove metals. Construction of a
dewatering pad to handle the saturated soils and a temporary groundwater treatment system will
be necessary.

The Remedy requires some shallow excavation of soils prior to cap installation so that there is no
net loss of flood storage within the floodplain (see Figure E-4 illustrating the locations of the
floodplain and Figure L-l for the locations of the "Cap Area"). The Remedy will include air
monitoring during the excavation/capping, as well as monitoring of the adjacent
wetlands/waterways, to ensure no contaminant releases impact human health and/or environment
during the cleanup activities, as required. For the Remedy on the Murphy and Abeijona
Properties, the existing building concrete foundation and slab conditions may be evaluated and
assessed during design for adequacy to serve as a component of the cap, assuming they satisfy
the remedial action objectives and impermeable cap standards established by ARARs. The
Remedy assumes these existing Murphy and Aberjona building concrete foundations and slabs
are in good condition and will serve as adequate cap. For the Whitney Property, any concrete
foundation and slab remaining intact after building demolition may be evaluated and assessed
during cap design for adequacy of satisfying the remedial action objectives and ARARs
impermeable cap standards. Approximately 5,200 cubic yards, 6,900 cubic yards and 300 cubic
yards of soil (a total of 12,400 cubic yards) will be excavated from the Whitney, Murphy and
Aberjona Properties, respectively, to facilitate capping. A conceptual plan view of the "Cap
Area" is provided in Figure L-l, and conceptual cap designs are provided on Figure L-5.
Alternative cap designs will be considered during remedial design. If thinner caps can be
designed and constructed while continuing to meet performance standards, then the amount of
material required to be excavated may be further minimized.

Approximately 18,000 cubic yards of contaminated soil will be excavated throughout the SWP.
Soil and all other media generated by the remedial action will be evaluated to determine if it
meets the definition of a listed hazardous waste or if it exceeds characteristic hazardous waste

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standards. Portions may also be Toxic Substance Control Act (TSCA) waste, based upon existing
data and pre-design investigations. Pre-design investigations will further characterize the extent
of contamination (including PCBs) and excavated soils will be managed on-site based on
contaminant characteristics, prior to being transferred off-site for disposal at a properly licensed
facility. Amendments, such as Portland cement, may be added to the excavated soil to meet off-
site disposal facility standards, if required. Prior to refilling the excavations, a geotextile fabric or
equivalent will be placed to visually distinguish the clean imported material from the underlying
impacted material left in place. The excavations will be backfilled with clean soil (with
amendments, as applicable), and the remaining soils exceeding cleanup levels will be covered
with the impermeable cap to prevent direct contact, minimize movement of soil contaminants to
groundwater (e.g., leaching), and mitigate the potential for erosion to result in impacts to the
wetland/floodplain. The cap within the 500-year floodplain will be designed, constructed, and
maintained to prevent any releases in the event of flooding (up to a 500-year flood event).
Restoration will include returning the area to the pre-existing conditions, and applying seed
(native species to the extent practicable), mulch and/or soil amendments to restore the disturbed
areas. The properties will be restored to original grades to prevent flood storage loss within the
floodplain. Cleanup levels for soil are shown in Table L-2 (see Appendix B).

Under TSCA regulatory standards at 40 C.F.R. §761.61(c), the Region has made a determination
that the manner of sampling, storage, cleanup, and disposal of PCB-contaminated soil as set out
in this Record of Decision will not pose an unreasonable risk of injury to health or the
environment. See TSCA Determination included as Appendix E to this ROD.

NAPL Remediation

The selected remedy component for NAPL, Excavation and Off-Site Disposal, includes the
following components:

•	A pre-design investigation to define the extent of NAPL and NAPL-impacted soils;

•	Bench-scale testing of soil amendments (e.g. ZVI) for backfill to treat and mitigate
localized soil and groundwater contamination;

•	Sequencing Plan for implementing the NAPL remedy in a manner that minimizes
disruptions to on-going business operations, to the extent practical;

• Installing any wetland/floodplain mitigation measures that may be required, establishing
stormwater/erosion control measures, clearing and grubbing of excavation areas,
relocating utilities to implement excavation, and installing temporary roads to excavation
areas;

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•	Installation of shoring around the perimeter of the excavation. The shoring will be
necessary to prevent collapse of the excavation sidewalls, impacts to the nearby
wetlands/floodplain, and damage to nearby structures;

•	Excavate approximately 6,000 cubic yards of NAPL and NAPL-impacted soil across the
SWP. Manage excavated soils/NAPL on-site based on their level of contamination and
then dispose off-site at a licensed facility. Amendments, such as Portland cement, may be
added to the excavated soil to meet off-site disposal facility standards, if required. Blend
soil at the bottom of the excavation below the water table with an amendment to provide
soil and localized groundwater treatment. Backfill excavations with amended soil below
the water table and clean soil above the water table, restoring the properties to original
grades for no net flood storage loss within the floodplain20;

•	Air monitoring during the excavation and on-site management of excavated materials, as
well as monitoring of the adjacent wetlands/waterways, to ensure no contaminant releases
impact human health and/or environment during the cleanup activities, as required;

•	De-water the portion of the excavation that extends below the water table and any
excavated NAPL-contaminated soils that require dewatering, treat the water through a
temporary treatment system and discharge the treated water to the Abeijona River (or
appropriate off-site disposal at permitted facility, or appropriate approved discharge to
the POTW), or appropriate approved on-site treatment and discharge from adjacent
Operable Unit-1 source area property (Wildwood Source Area Property); and,

•	Long-term monitoring (as part of the groundwater component of the cleanup) to confirm
no further presence of NAPL in groundwater); and

Figure L-2 provides a conceptual layout of the NAPL remedy. The Remedy includes the
excavation and off-site disposal of approximately 6,000 cubic yards of NAPL and NAPL-
impacted soil in specific areas where NAPL has historically been observed as indicated in
Figure L-2. The Remedy excavates NAPL and NAPL impacted soils within several portions of
the SWP, including the vicinity of monitoring wells MW-7, MW-16, MW-22, MW-23, MW-24,
and MW-25 at the Murphy Property and monitoring well WB-201S at the Whitney Property, to
approximately 6 feet below the water table (total depth of approximately 12 feet). Excavation
will continue in the shallow groundwater until sampling confirms that the excavation goals of
removing all the NAPL are met. The conceptual design also includes approximately 795 linear
feet of shoring driven to 20 feet below the ground surface to prevent collapse of the excavation
sidewalls and impacts to the nearby wetlands/floodplain.

20 Some NAPL excavation areas may overlap with soil remediation areas were an impermeable cap will be installed
over the area at grade.

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The excavation will proceed below the water table and require dewatering. Excavated saturated
NAPL-contaminated soils will also likely require dewatering prior to off-site disposal. The
dewatering water is expected to be treated to appropriate levels prior to proper discharge to the
Aberjona River (or appropriate off-site disposal at permitted facility, or appropriate approved
discharge to the POTW, or appropriate approved on-site treatment and discharge from adjacent
Operable Unit-1 source area property (Wildwood Source Area Property)). A dewatering system
to handle the saturated NAPL-contaminated soils and a temporary groundwater treatment system
will be necessary, and may include storage and settling tanks, filtration (e.g., bags filters), air
stripping to remove VOCs, activated carbon to remove PCBs (as well as VOCs), and ion
exchange resins to remove metals. Treated water will be discharged to a nearby surface water
body (e.g., Abeijona River) in accordance with ARAR requirements, discharged to the POTW,
or sent off-site for treatment and disposal.

The approximately 6,000 cubic yards of NAPL and NAPL-impacted soil will be managed on-site
and then transported off-site for disposal at a properly licensed facility. Amendments, such as
Portland cement, may be added to the excavated NAPL/soil to meet off-site disposal facility
standards, if required. NAPL/soil and all other media generated by the remedial action will be
evaluated to determine if it meets the definition of a listed hazardous waste or if it exceeds
characteristic hazardous waste standards. Portions may also be Toxic Substance Control Act
(TSCA) waste, based upon existing data and pre-design investigations. The excavations will be
backfilled with amended soil below the water table and clean soil above the water table. The
amendment will be designed to provide soil and localized groundwater treatment similar to the
soil remedy on the Whitney Property. Restoration will include returning the area to the pre-
existing conditions, and applying seed (native species, to the extent practicable), mulch and/or
soil amendments. To the extent that the NAPL removal area overlaps the cap areas delineated
under the soil remedy on the Murphy and Whitney Properties, the overlap areas will be capped.
The properties will be restored to original grades to prevent flood storage loss within the
floodplain.

Note that NAPL removal on the Whitney Property is expected to occur during and as part of the
Northern Whitney Soil Area excavations under the soil remedy (See Figure L-l). Hence, the
NAPL remedy costs are adjusted downward in Table L-5 to account for NAPL removal under
the soil remedy on the Whitney Property.

The selected remedy component for NAPL involves NAPL and associated NAPL-impacted soil
excavation at the Whitney and Murphy Properties, and disposal of these excavated materials at
an approved off-site disposal facility. Excavation would continue until sampling confirms that
the NAPL is completely removed, to the extent practicable.

Under TSCA regulatory standards at 40 C.F.R. §761.61(c), the Region has made a determination
that the manner of sampling, storage, cleanup, and disposal of PCB-contaminated NAPL as set
out in this Record of Decision will not pose an unreasonable risk of injury to health or the
environment. See TSCA Determination included as Appendix E to this ROD.

Groundwater Remediation

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The selected remedy component for groundwater, Pump and Treat and Institutional Controls,
includes the following components:

•	Pre-design investigations to refine the horizontal and vertical extents of groundwater
exceeding cleanup levels and to assist in the development of the groundwater treatment
system design;

•	Sequencing Plan for implementing the Groundwater remedy in a manner that minimizes
disruptions to on-going business operations, to the extent practical;

•	Optimal location for a groundwater treatment facility;

•	Design and construction of the groundwater treatment and monitoring system, including
any measures to address stormwater and wetlands/floodplain mitigation issues;

•	Operation and maintenance of the groundwater treatment system to prevent contaminant
migration and remove groundwater contaminants21;

•	Testing and off-site disposal of any contaminated media generated from the treatment
system or from monitoring to a disposal facility licensed to accept the contaminated
media; and,

•	Long-term Monitoring of groundwater to evaluate effectiveness of pump and treat system
and operation and maintenance of the monitoring well system. The effectiveness of the
remedy would be evaluated by sampling groundwater monitoring wells until cleanup
levels are achieved.

Figure L-3 provides a conceptual layout of the groundwater remedy. The groundwater remedy
includes: 1) pre-design investigation activities and groundwater sampling to assist in
groundwater treatment system design, which may include treatment components such as bag
filters, activated carbon vessels, metals polishing vessels, air strippers, vapor phase activated
carbon, etc., and to determine the pumping rates, locations and depth of extraction wells;

2) water treatment plant design, and development of health and safety plan; 3) construction of the
groundwater pump and treat system, including the treatment plant and treatment components,
trenching of associated piping to transfer water to the treatment plant, and discharge piping for
discharge of treated water; 4) operation and maintenance of the treatment system components to
reduce contaminant concentrations and achieve groundwater cleanup standards, and prevent
contaminant groundwater migration into the wetlands or beyond the SWP; 5) long-term
groundwater monitoring to determine long-term effectiveness of pump and treat system;
6) operation and maintenance of the monitoring well system, and 7) implementation of
Institutional Controls to prevent disturbance of the components of the remedy, prohibit the use of
groundwater until cleanup levels are met, and to require evaluation of the vapor intrusion

21 Additional groundwater treatment will occur through the use of treatment amendments mixed into saturated
subsurface soil as part of the soil and NAPL components of the remedy, discussed above.

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pathway if a change in usage of any of the existing buildings is contemplated or as part of new
building construction, including any addition to existing buildings on any of the properties. Pre-
design investigation activities will include consideration of the age and upgrades to the adjacent
Wildwood Source Area Property groundwater treatment system plant to accommodate and
adequately treat extracted groundwater from the SWP in lieu of constructing a groundwater
treatment plant on the SWP (while continuing to treat extracted water from the Wildwood Source
Area Property). Cleanup levels for groundwater are shown in Table L-l (see Appendix B).

Under TSCA regulatory standards at 40 C.F.R. §761.61(c), the Region has made a determination
that the manner of sampling, extraction, treatment, and disposal of PCB-contaminated
groundwater and treatment media as set out in this Record of Decision will not pose an
unreasonable risk of injury to health or the environment. See TSCA Determination included as
Appendix E to this ROD.

Wetland Sediment/Soil Remediation

The selected remedy component for the wetland sediment/soil, Deep Excavation, Off-Site
Disposal, Backfill Cover, and Wetland Restoration, includes the following components:

•	Pre-design investigation to refine the vertical and horizontal extent of wetland
sediment/soil exceeding cleanup levels;

•	Sequencing Plan for implementing the NAPL remedy in a manner that minimizes
disruptions to on-going business operations, to the extent practical;

•	Installing any wetland/floodplain mitigation measures that may be required, establishing
stormwater/erosion control measures, clearing and grubbing of excavation areas,
installing temporary roads to excavation areas, and pre- and post-excavation land
surveying;

•	Site preparation; establishing a sediment/soil dewatering area; de-watering both the
excavation, as required, and any excavated contaminated sediments/soils that require
dewatering; water treatment through a temporary de-watering and treatment system; and
discharge to the Aberjona River or appropriate approved POTW, or disposal at an
appropriate off-site permitted disposal facility, or appropriate approved on-site treatment
and discharge from adjacent Operable Unit-1 source area property (Wildwood Source
Area Property);

•	Excavate approximately 7,000 cubic yards of wetland sediment/soil exceeding cleanup
levels (approximately 63,000 square feet of wetland area). Perform confirmation
sampling to demonstrate compliance with cleanup levels. Manage excavated
sediments/soils on-site based on their level of contamination. Add amendments, if
required, to dewatered sediment/soil to allow off-site disposal. Dispose of dewatered
sediment/soil and any treatment media at a licensed off-site disposal facility;

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• Backfill excavations to pre-remediation grades with clean wetland soil, and restore the
wetland habitat, also restore any altered floodplain habitat, as required;

• Air monitoring during the excavation/backfilling, as well as monitoring of the adjacent
wetlands/waterways, to ensure no contaminant releases impact human health and/or the
environment during the cleanup activities, as required; and,

• Post-remediation monitoring of plantings and ground surfaces to ensure
floodplain/wetland restoration goals are met.

Figure L-4 provides a conceptual layout of the wetland sediment/soil remedy, and illustrates the
location of Wetland Sediments (identified within the Murphy Wetland as "SEASONALLY
PONDED AREA") and the location of Wetland Soils (identified within the Murphy Wetland as
"FORESTED/SCRUB-SHRUB SWAMP"). The wetland sediment/soil remedy includes the
excavation and off-site disposal of approximately 7,000 cubic yards of contaminated wetland
sediment/soil. The wetland sediment/soil remedy includes excavation to remove all wetland
sediment/soil with contaminants in excess of the wetland sediment/soil cleanup levels. Deeper or
shallower excavations may be conducted in specific areas of the wetland, depending on pre-
design sampling results. Confirmation sampling will be performed to demonstrate compliance
with excavation goals. The wetland sediment/soil remedy includes backfilling the excavation to
pre-remediation grades and includes restoration of the floodplain/wetland habitat.

As the excavation proceeds below the water table it will be necessary to dewater the excavation.
Extracted water is expected to contain PCBs, SVOCs, VOCs, and metals. A temporary
dewatering system will be designed and implemented to treat extracted water prior to proper
discharge and may include storage tanks, filtration, air stripper, activated carbon, ion exchange
resins, etc. Treated water will be discharged to a nearby surface water body (e.g., Aberjona
River) or appropriate off-site disposal at permitted facility, or appropriate approved discharge to
the POTW, or appropriate approved on-site treatment and discharge from adjacent Operable
Unit-1 source area property (Wildwood Source Area Property)).

The approximately 7,000 cubic yards of contaminated sediment/soil excavated will be
transferred off-site for disposal at a properly licensed facility. Excavated sediments/soils will be
managed on-site based on their level of contamination. Additional amendments, if required, will
be added to dewatered sediment/soil to allow off-site disposal. The excavations will be backfilled
with clean wetland soil to pre-remediation grades. Floodplain/wetland restoration will include
planting of native species to restore the disturbed areas. Wetland/floodplain species would be
planted in accordance with the restoration plan. The wetland and any altered floodplain will be
restored to original grades to prevent flood storage loss. Plantings and visible ground surfaces
will be inspected and maintained as required by the restoration plan and ARARs requirements.
The monitoring period is assumed to be at least three years. Cleanup levels for wetland
sediments/soils are shown in Tables L-3 and L-4 (see Appendix B).

Under TSCA regulatory standards at 40 C.F.R. §761.61(c), the Region has made a determination
that that manner of sampling, storage, cleanup, and disposal of PCB-contaminated wetland

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sediment/soil as set out in this Record of Decision will not pose an unreasonable risk of injury to
health or the environment. See TSCA Determination included as Appendix E to this ROD.

Remedy Modifications

The selected remedy may change somewhat as a result of the remedial design and construction
process. Changes to the remedy described in this Record of Decision will be documented in a
technical memorandum in the Administrative Record for the SWP, an Explanation of Significant
Differences or a Record of Decision Amendment, as appropriate.

3. Summary of the Estimated Remedy Costs

Table L-5 in Appendix B list a summary of the major capital and O&M cost elements for the
selected remedy. These tables present the major construction and O&M activities required to
implement each remedy component along with their associated unit and total costs. Note that
NAPL removal on the Whitney Property is expected to occur during and as part of the Northern
Whitney Soil Area excavations under the SW-3 Alternative. Hence, the N-3 Alternative costs are
adjusted downward in Table L-5 to account for NAPL removal under the SW-3 Alternative.

The information in the cost estimate summary tables is based on the best available information
regarding the anticipated scope of the remedial alternative. Changes in the cost elements are
likely to occur as a result of new information and data collected during the engineering design of
the remedial alternative. Major changes may be documented in the form of a memorandum in
the Administrative Record file, an ESD, or a ROD amendment. This is an order-of-magnitude
engineering cost estimate that is expected to be within +50 to -30 percent of the actual project
cost.

The total estimated cost of the Selected Remedy is $19.1 million.

4. Expected Outcomes of the Selected Remedy

The primary expected outcome of the selected remedy is that the soils underlying the SWP will
no longer present an unacceptable risk to human health via direct contact for a recreational
scenario, and will no longer act as a source of groundwater contamination after the remedy is put
into place, and no longer act as a source of surface contaminant migration to the wetland.
Wetland sediment/soil in the Murphy Wetland will no longer present risks to human health or the
environment following completion of the remedial action. In addition, NAPL will no longer
serve as a continuing source of impacts to the aquifer, and no longer act as a source of surface
contaminant migration to the wetland. Groundwater contamination underlying the SWP will be
treated and contained once the extraction/treatment system is put into place. The groundwater is
expected to be restored to its permissible, beneficial use as a future potential drinking water
source within approximately 20 years and will no longer present an unacceptable risk to human
health. It is anticipated that the selected remedy will also provide socio-economic and
community revitalization impacts such as increased property values, increased tax revenues due
to redevelopment, and enhanced human uses of ecological resources.

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The effectiveness of the groundwater remedy will be determined based upon attainment of the
cleanup levels outlined in Table L-l, as well as any additional site-related COCs added through
subsequent decision documents. A monitoring program will be implemented in order to evaluate
remedy performance and progress towards attainment. The details of the monitoring program
will be established during the remedial design phase and will include the preparation of a long-
term monitoring plan, but initial monitoring is expected to include evaluation of all site-related
contaminants such as VOCs, SVOCs, metals, pesticides and PCBs. Monitoring scope and
frequency could change over time based on technical analysis of the remedy, optimization
studies, revised conceptual site model, or other information, as determined by EPA.

The determination that all cleanup levels have been met will consider historical and current
monitoring data, contaminant distribution, trend analysis, and the appropriateness of the
compliance monitoring program (i.e., locations, frequency of monitoring, sampling parameters).
After all groundwater, soil, and wetland sediment/soil cleanup levels (as shown in Tables L-l to
L-4) have been met, EPA will perform a risk evaluation which considers additive risk from
remaining COCs considering all potential routes of exposure to document the residual risk based
on exposure to soil, wetland sediment/soil, and/or groundwater at the SWP. The residual risk
evaluation will document the potential risk associated with the concentrations of the COCs
remaining in soil, wetland sediment/soil, and/or groundwater at the SWP (if detected).

a. Cleanup Levels

Cleanup levels were developed for the COCs identified in the human health and ecological risk
assessments. COCs are the chemicals found at the SWP that, based on the results of the risk
assessment, were determined to pose an incremental lifetime cancer risk greater than 1 in 1
million (10"6) or an HI greater than 1. COCs were identified for exposure areas that posed A) a
cancer risk in excess of an Incremental Lifetime Cancer Risk (ILCR) of 10"4, B) an HI greater
than 1, or C) a significant ecological risk. Although the PCB TEQ was identified as a COC in
groundwater, soil and wetland sediment/soil, cleanup levels have not been developed for the
PCB TEQ because the medium-specific cleanup levels for total PCB have been determined to be
protective of risk associated with dioxin-like PCBs (see Appendix C in the FS for a complete
discussion).

1. Groundwater Cleanup Levels

The cleanup levels for most Chemicals of Concern (COCs) in groundwater were selected based
on federal MCLs, or risk-based cleanup goals. For those COCs that do not have a federal or state
ARAR at the time this ROD was developed, a risk-based cleanup level was calculated. If a value
described by any of the methods described above was not capable of being detected with good
precision and accuracy, or was below what was deemed to be the background value, then the
practical quantification limit or background value was selected as the cleanup level. The selected
cleanup levels are shown in Table L-l (see Appendix B as well as Attachment 2 of the 2017 FS
Report Addendum - Technical Memorandum for cleanup level development). Many of these
cleanup levels represent federal MCLs, but some are based on a cancer risk level of 1 x 10 s or an

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HQ of 1 (risk-based cleanup level).

The cleanup levels are based on a residential scenario with potential future cumulative cancer
risks greater than 10"4 or target organ His greater than 1 considering the ingestion, dermal
contact, and inhalation exposure pathways. Risk-based PRG development was required for each
chemical with an individual cancer risk above 10"6 or with an HQ above 1. Based on EPA
revisions to default exposure parameters and toxicity values since the release of the FS,
Attachment 2 of the 2017 FS Report Addendum - Technical Memorandum contains updated
cleanup level development.

The human health risk-based PRGs provided in Attachment 2 of the 2017 FS Report Addendum
- Technical Memorandum correspond to target cancer risk levels of 10"6, 10"5, and 10"4 and a
target non-cancer HQ of 1. For each of the contaminants, risk-based PRGs were calculated using
equations and exposure assumptions initially presented in Appendix C of the FS, which were the
same as those used in the baseline HHRA except as noted in the following paragraphs. Toxicity
values used in the calculation of the risk-based PRGs are presented in Section G of this ROD.

As noted in Section G of this ROD, the baseline HHRA was completed in early 2014. After the
completion of the baseline HHRA, EPA finalized a Directive to update standard default exposure
factors and frequently asked questions associated with these updates. These updated standard
default exposure factors have been utilized to develop the risk-based cleanup levels for
groundwater (see Attachment 2 of the 2017 FS Report Addendum - Technical Memorandum).

The human health risk-based PRG selection process for each contaminant is summarized in
Appendix C of the FS and in Attachment 2 of the 2017 FS Report Addendum - Technical
Memorandum.

Consistent with EPA's 1996 Final Ground Water Use and Value Determination Guidance, and
the Commonwealth of Massachusetts' Comprehensive State Groundwater Protection Program
(CSGWPP), MassDEP has developed a "Use and Value Determination" of the groundwater
relative to the Wells G&H Site. The purpose of the Use and Value Determination is to identify
whether the aquifer at the Site should be considered of "High," "Medium," or "Low" use and
value. In the development of its Determination, MassDEP applied the criteria for groundwater
classification as promulgated in the MCP. The classification contained in the MCP considers
criteria similar to those recommended in the Use and Value Guidance. MassDEP determined
that there is a Medium use and value for the Site area groundwater. Therefore, EPA has selected
cleanup levels based on federal and state drinking water standards, or Maximum Contamination
Levels (MCLs), and risk-based criteria that support this use as a future potential drinking water

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source.22

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2. Soil Cleanup Levels

Human health-based soil cleanup levels were initially developed in Appendix C of the FS
(AECOM, 2016) for a recreational user exposure scenario, based on risks presented earlier in
Section G of this ROD for the Murphy and Whitney Properties. EPA has determined that
cleanup levels will be established which allow for recreational use of the SWP. While there was
also unacceptable risk calculated for a future trespasser exposed to soil at the Whitney Property,
the recreational user scenario is the more conservative scenario which results in lower cleanup
levels. Similar to groundwater, Attachment 2 of the 2017 FS Report Addendum - Technical
Memorandum presents revised cleanup level development information.

Cleanup levels for chemicals of concern (COCs) in surface or subsurface soil exhibiting an
unacceptable cancer or non-cancer risk have been established such that they are protective of
human health. In the FS and 2017 FS Report Addendum, PRGs were developed for soil
associated with potential future cumulative cancer risks greater than 10"4 or target organ His
greater than 1 considering the ingestion and dermal contact exposure pathways in a recreational
exposure scenario. For those soils, risk-based PRG development was required for each chemical
with an individual cancer risk above 10"6 or with an HQ above 1 (see Attachment 2 of the 2017
FS Report Addendum - Technical Memorandum and Appendix C of the FS). These
contaminants include TCE, vinyl chloride, bis(2-ethylhexyl)phthalate, PCBs, pesticides, arsenic,
and hexavalent chromium at the Whitney Property and thallium at the Murphy Property.

The human health risk-based PRGs provided in Attachment 2 of the 2017 FS Report Addendum
- Technical Memorandum correspond to target cancer risk levels of 10"6, 10"5, and 10"4 and a
target non-cancer HQ of 1. The risk-based PRGs are applicable to soils up to a depth of 15 feet
below ground surface at the Whitney and Murphy Properties. For each of the contaminants, risk-
based PRGs were calculated using equations and exposure assumptions presented in Attachment
2 of the 2017 FS Report Addendum - Technical Memorandum. Toxicity values used in the
calculation of the risk-based PRGs are presented in Section G of this ROD, while Attachment 2
of the 2017 FS Report Addendum - Technical Memorandum presents the dermal absorption
factors used during PRG development. An oral relative bioavailability factor of 0.6 is now
recommended by EPA for evaluation of risks and calculation of PRGs for arsenic in soil. The
bioavailability factor was not used in the baseline HHRA, but has been applied during PRG
development.

22 The risk associated with the MCLs for ethylbenzene, 1,4-dichlorobenzene, 1,2,4-trichlorobenzene, 1,1,2-
trichloroethane, heptachlor, heptachlor epoxide, arsenic and vinyl chloride fall outside (above) the Superfund risk
range; however, EPA has determined that MCLs are protective values for drinking water.

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exposure factors have been utilized to develop the risk-based cleanup levels for soil (see
Attachment 2 of the 2017 FS Report Addendum - Technical Memorandum), along with the
revised toxicity values, as discussed in Section G of this ROD.

The human health risk-based soil cleanup levels for each contaminant are summarized in Table
L-2 in Appendix B of this ROD. The cleanup levels are selected by considering the ARARs,
risk-based PRGs, leaching PRGs, quantitation limits, and reference/background data.

Risk-based cleanup levels for soil correspond to a cancer risk level of 1 x 10"6 for TCE, vinyl
chloride, bis(2-ethylhexyl)phthalate and pesticides, a cancer risk level of 1 x 10"5 for arsenic and
hexavalent chromium, and a noncarcinogenic HQ of 1 for total PCBs and thallium. See also the
TSCA determination in Appendix E of this ROD and EPA policy (Guidance on Remedial
Actions for Superfund Sites with PCB Contamination, OSWER Directive #9355.4-01,
EPA/540/G-90/007, August 1990) for further information. Per CERCLA and the NCP, EPA
does not require cleanup to below background levels. Therefore, cleanup levels for the arsenic
and hexavalent chromium are set at a 1 x 10"5 cancer risk level so the cleanup levels are not
below a background levels.

These risk-based cleanup levels must be met at the completion of the remedial action in surface
and subsurface soils (to a depth up to 15 feet below ground surface) at the Murphy Property for
thallium, and for all other compounds with risk-based cleanup levels at the Whitney Property.
These soil cleanup levels attain EPA's risk management goal for remedial actions and have been
determined by EPA to be protective.

Available data developed in the RI and the baseline HHRA suggest that volatile organic
compounds and petroleum hydrocarbon fractions in area soils leach to groundwater thereby
contaminating groundwater. This phenomenon may result in an unacceptable risk to those who
use contaminated groundwater in the future as a source of potable water. Therefore, cleanup
levels for VOCs and petroleum hydrocarbon fractions in soils were also established to protect the
aquifer from potential soil leachate. These leachability soil cleanup levels presented on Table L-
2 are applicable to soils located above the water table on the Murphy, Whitney and Aberjona
Properties.

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The partitioning model used to develop the Soil Screening Levels (SSLs) presented on EPA's
RSL May 2016 tables was used to estimate residual soil levels that are not expected to impair
future groundwater quality. Appendix C of the 2016 FS describes the development of the
leachability cleanup levels. The cleanup levels for groundwater were identified as described in
Section L.l (Groundwater Cleanup Levels). The SSLs listed on the RSL table were adjusted
upward 10-fold, consistent with the assumed dilution attenuation factor of 10 applicable to the
SWP, rather than the default value of 1 used to develop the default SSLs on the RSL table. The
leaching model was arranged such that the model output was consistent with the Cleanup Levels
for groundwater. If the predicted protective soil level was not capable of being detected with
good precision and accuracy, then the practical quantification limit was selected as the cleanup
level for soils.

Table L-2 summarizes the leachability soil cleanup levels established to protect public health
and the aquifer and were developed for soil contaminants that have the potential to leach.

These leachability cleanup levels must be achieved at the completion of the remedial action for
soils above the water table at the Murphy, Whitney and Abeijona Properties. These soil cleanup
levels attain EPA's risk management goal for remedial actions and have been determined by
EPA to be protective.

3. Wetland Sediment/Soil Cleanup Levels
Human Health

Wetland sediment/soil cleanup levels were initially developed in the FS (AECOM, 2016) for a
recreational user exposed to PCBs, CI 1-C22 aromatic hydrocarbons and lead at the Murphy
Wetland. While there was also unacceptable risk calculated for a trespasser due to PCBs, the
recreational visitor scenario is the more conservative scenario which results in lower cleanup
levels. Similar to groundwater and soil, Attachment 2 of the 2017 FS Report Addendum -
Technical Memorandum presents revised cleanup level development information.

The cleanup level for PCBs and CI 1-C22 aromatics in wetland sediment/soil have been
established such that they are protective of human health. Risk-based PRGs were developed for
wetland sediment/soil associated with a potential future target organ HI greater than 1
considering the ingestion and dermal contact exposure pathways in a recreational user exposure
scenario.

The human health risk-based PRGs provided in Attachment 2 of the 2017 FS Report Addendum
- Technical Memorandum correspond to target cancer risk levels of 10"6, 10"5, and 10"4 and a
target non-cancer HQ of 1. Risk-based PRGs were calculated using equations and exposure
assumptions presented in Attachment 2 of the 2017 FS Report Addendum - Technical
Memorandum. Toxicity values used in the calculation of the risk-based PRGs are presented in
Section G of this ROD, while the dermal absorption factors used during PRG development are
presented in Attachment 2 of the 2017 FS Report Addendum - Technical Memorandum.

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As noted in Section G of this ROD, the baseline HHRA was completed in early 2014.
Subsequently, EPA finalized a Directive to update standard default exposure factors and
frequently asked questions associated with these updates. These updated standard default
exposure factors have been utilized to develop the risk-based cleanup levels for wetland
sediment/soil (see Attachment 2 of the 2017 FS Report Addendum - Technical Memorandum).

The human health risk-based wetland sediment/soil cleanup levels are summarized in Table L-3
in Appendix B of this ROD. The cleanup levels are selected by considering the ARARs, risk-
based PRGs, quantitation limits, and reference/background data.

The human health-based cleanup level for PCBs and the CI 1-C22 aromatic fraction in wetland
sediment/soil correspond to an HQ of 1. See also the TSCA determination in Appendix E of this
ROD and EPA policy (Guidance on Remedial Actions for Superfund Sites with PCB
Contamination, OSWER Directive #9355.4-01, EPA/540/G-90/007, August 1990) for further
information. For lead, the Integrated Exposure and Uptake Biokinetic (IEUBK) model was used
to develop a cleanup level applicable for young children less than 7 years of age as the most
sensitive receptor group. The lead cleanup level is protective of 95% of the sensitive population
against blood lead levels in excess of 5 ug/dl blood. See Attachment 2 of the 2017 FS Report
Addendum - Technical Memorandum for further details concerning the model assumptions
applied for the lead modeling.

These cleanup levels must be achieved at the completion of the remedial action in wetland
sediment/soil in the Murphy Wetland. These wetland sediment/soil cleanup levels attain EPA's
risk management goal for remedial actions and have been determined by EPA to be protective.

Ecological

The results of the ecological risk assessment indicated that there are potential risks to the benthic
community in the Seasonally Ponded Area and to mammals foraging in both the Seasonally
Ponded Area and Forested/Shrub Wetland. Risks were determined to be primarily associated
with sediment/surface soil concentrations of PCB aroclors and chromium while lead, and to a
lesser extent, zinc also present risk to benthic invertebrates within the Seasonally Ponded Area.
Consequently, these four constituents were identified as COECs in the Seasonally Ponded Area
sediment and/or Forested/Shrub Wetland surface soil.

PRGs for sediment in the Seasonally Ponded Area were derived by identifying 'probable effect'
COEC concentrations and background COEC concentrations. The 'probable effect'
concentrations were identified as the COEC concentrations reported in the literature to result in
significant toxicity to benthic invertebrates while background levels were based on mean
concentrations of COECs detected in the reference wetland. In addition, for the mammalian
receptors (muskrat and shrew), the selected cleanup levels were calculated as the geometric mean
of the 'no effect' and 'low effect' values. Ecological cleanup levels for sediment and surface soil
are presented in Table L-4 in Appendix B of this ROD. Documentation of the ecological PRGs
is provided in Appendix C of the FS (AECOM, 2016).

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These cleanup levels must be met at the completion of the remedial action in sediment in the
Seasonally Ponded Area and in surface soil for the Forested/Shrub Wetland. These wetland
sediment/surface soil cleanup levels attain EPA's risk management goal for remedial actions and
have been determined by EPA to be protective.

M. STATUTORY DETERMINATIONS

The remedial action selected for implementation at the SWP is consistent with CERCLA and, to
the extent practicable, the NCP. The selected remedy is protective of human health and the
environment, will comply with ARARs and is cost effective. In addition, the selected remedy
utilizes permanent solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable, and partially satisfies the statutory preference
for treatment that permanently and significantly reduces the mobility, toxicity or volume of
hazardous substances as a principal element.

1. The Selected Remedy is Protective of Human Health and the Environment

The remedy at the SWP will adequately protect human health and the environment by
eliminating, reducing, or controlling exposures to human and environmental receptors through
treatment, engineering controls and Institutional Controls. More specifically, for the soil
component of the remedy, excavation of principal threat waste material in the Northern Whitney
Soil Area, and the blending of remaining contaminated soil below the water table with an
amendment prior to backfilling to provide soil and localized groundwater treatment will be
protective of human health and the environment through prevention of precipitation infiltration
into the groundwater and prevention of direct contact with soils. The soil component of this
remedy also includes impermeable caps over soils exceeding the soil cleanup levels on the
Whitney, Murphy and Abeijona Properties to reduce soil exposure risks and/or prevent
contaminant movement to groundwater or to the wetlands at concentrations that exceed ARARs
and/or risk-based standards. Within the 500-year floodplain of the SWP the caps will be installed
below the surface soil level so there is no loss of flood storage capacity. Excavation and off-site
disposal of Northern Whitney Soil Area soils that generally cannot be reliably contained will
prevent direct contact with soils, prevent erosion and runoff of hazardous waste/contaminated
soils, and prevent precipitation infiltration into the groundwater. Excavation and off-site
disposal of areas where PCB-contaminated soil exists over the cleanup level will meet TSCA
requirements for disposal of PCB remediation waste. Institutional Controls to maintain the
integrity of the soil caps and other remedial components; prevent development of the properties
for residential, school, and daycare use (exclusive of the existing residence at the Aberjona
Property); to prohibit use of contaminated groundwater until cleanup levels are met; and to
require evaluation of the vapor intrusion pathway if a change in usage of any of the existing
buildings is contemplated or as part of new building construction, including any
addition/alteration to existing buildings on any of the properties. To facilitate future use and
redevelopment of the SWP consistent with the cleanup, Institutional Controls will be established

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to preserve the remedy, and appropriately manage impacted soil and groundwater encountered
during future intrusive activities (e.g. installing subsurface utilities, building foundations/slabs,
etc).

For the NAPL component of the remedy, excavation of principal threat waste material in the
NAPL areas on the Whitney and Murphy Properties and the blending of soil at the bottom of the
excavation below the water table with an amendment to provide soil and localized groundwater
treatment will be protective of human health and the environment through prevention of
precipitation infiltration into the groundwater and discharge to the Murphy Wetland. Excavation
and off-site disposal of NAPL, to the extent practicable, will prevent direct contact with NAPL
that contribute to exceedances of groundwater and/or soil ARAR and risk-based standards and
prevent precipitation infiltration into the groundwater and discharge to the wetland area.
Institutional Controls for soil and groundwater will prevent exposure to any NAPL present in
those media after the NAPL excavation and off-site disposal.

Permanent removal of all contaminated wetland sediment/soil from the Murphy Wetland
exceeding cleanup levels will reduce the threat of human exposure to contaminants via direct
contact and will also reduce risks to ecological receptors from wetland sediment/soil contact to
levels protective of the benthic invertebrate population and insectivorous mammals. The
excavation and removal of all COCs above cleanup levels present in wetland sediments/soils will
provide overall protection to human health and the environment by quickly reducing human
health and ecological risks to acceptable levels. Institutional Controls are not required for the
wetland sediment/soil component of this remedy.

The groundwater component of the remedy will reduce exposure levels to protective ARAR
levels or, in the absence of protective ARAR levels, to within EPA's generally acceptable risk
range of 10"4 to 10"6 for carcinogenic risk and below the HI of 1 for noncarcinogens in
groundwater as outlined in Table L-l (Groundwater Cleanup Levels) for the purposes of this
CERCLA remediation. It should be noted that the groundwater remediation at the SWP
addresses contamination related to the SWP only. Institutional Controls are required to prohibit
use of contaminated groundwater until cleanup levels are met and require the evaluation of vapor
intrusion risks if a change in usage of any of the existing buildings is contemplated or as part of
new building construction, including any addition/alteration to existing buildings on any of the
properties. Use of a vapor barrier or subslab system may be appropriate to mitigate the vapor
intrusion pathway in instances of future development/construction of new or occupied buildings.

The selected remedy will reduce potential human health risk levels such that they do not exceed
EPA's acceptable risk range of 10"4 to 10"6 for incremental carcinogenic risk and such that the
non-carcinogenic hazard is below the HI of 1. It will reduce potential human health risk levels to
protective ARARs levels (i.e., the remedy will comply with ARARs and risk-based standards
derived using TBC criteria). In addition, unacceptable ecological risks associated with exposure
to wetland sediment/soil will be eliminated by permanent removal of impacted wetland
sediment/soil and wetland restoration. Implementation of the selected remedy will not pose any
unacceptable short-term risks or cause any cross-media impacts.

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2. The Selected Remedy Complies with ARARs

The selected remedy will comply with all federal and any more stringent state ARARs that
pertain to the Site. A detailed list of ARARs/To Be Considered requirements for the selected
remedy is included in Appendix D of this ROD. A discussion of the more significant ARAR
issues is included below.

Wetland Impacts

The cleanup plan selected by EPA includes activities that would impact wetlands. Before EPA
selected a cleanup plan that will impact wetlands, Section 404 of the Clean Water Act, regulatory
requirements at 44 C.F.R. Part 9, and Executive Order 11990 (Protection of Wetlands) required
EPA to make a determination that there is no practicable alternative to conducting work that will
impact wetlands and that the selected remedy is the LEDPA under the federal Clean Water Act.
EPA has determined that because significant levels of contamination exist in wetlands within the
SWP cleanup areas, there is no practicable alternative to permanently removing the contaminants
from these wetlands. EPA has determined that the cleanup activities that impact wetlands are the
LEDPA because they will permanently remove contaminants that are impairing the wetlands and
that any wetland resources altered by the cleanup will be restored to the original grade and with
native vegetation.

EPA will minimize potential harm and avoid adverse impacts on wetland resources, to the extent
practical, by using best management practices to minimize harmful impacts on the wetlands,
wildlife or habitat. Wetlands will be restored and/or replicated consistent with the requirements
of federal and state wetlands protection laws.

Floodplain Impacts

The cleanup plan selected by EPA includes activities that result in the occupancy and
modification of the 500-year floodplain. Before EPA selected a cleanup plan, regulatory
requirements at 44 C.F.R. Part 9 and Executive Order 11988 (Floodplain Management) required
EPA to make a determination that there is no practicable alternative to altering floodplain
resources. EPA has determined there is no practicable alternative to occupancy and modification
of the Abeijona River floodplain. EPA will avoid or minimize potential harmful temporary and
permanent impacts on floodplain resources within the 500-year floodplain, to the extent
practical, within the cleanup areas including the Murphy Wetland. In addition, the cleanup plan
selected by EPA includes provisions for no net flood storage loss (e.g., soil removed prior to cap
installation so no net flood storage loss, sediments removed and clean wetland soils backfilled to
original grades, etc.).

TSCA Requirements

Management of PCB-contaminated sediments and soils at the SWP must comply with 40 C.F.R.

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Part 761 of TSCA. EPA has determined that the risk-based PCB cleanup levels of 5.3
milligrams/kilogram for PCBs for recreational exposure in soil, 1.9 milligram/kilogram for PCBs
for ecological exposure in contaminated wetland sediment, and 1.3 milligram/kilogram for PCBs
for ecological exposure in contaminated wetland soil at the SWP will not pose an unreasonable
risk of injury to health or the environment. Risks from unrestricted exposure to PCBs between 1
milligram/kilogram and 5.3 milligrams/kilogram for PCBs in contaminated soil will be addressed
by Institutional Controls that will prevent residential, school, and daycare development
(throughout the SWP except within the existing residential area within the Abeijona parcel and
in the Murphy Wetland where no residential exposure is anticipated). The soil excavation
component of the cleanup plan will remove PCBs greater than or equal to 50
milligrams/kilogram of PCBs in soil, with disposal off-site at a licensed facility. Remaining
PCB-contaminated soil above the PCB soil cleanup level will be capped with an impermeable
cap to prevent exposure and contaminant migration. In addition, PCB-contaminated NAPL will
be removed from the subsurface to the extent practicable. NAPL contaminated with equal or
greater than 50 milligrams/kilogram of PCBs will be disposed of at a licensed TSCA or RCRA
compliant disposal facility. Excavated soils with PCB-contaminated soils with less than 500
milligrams/kilogram and 1 milligram/kilogram will be disposed of at an appropriated licensed
off-site disposal facility. The wetland sediment/soil excavation component of the cleanup plan
will remove PCBs greater than or equal to 50 milligrams/kilogram of PCBs in soil, with disposal
off-site at a TSCA or RCRA licensed facility. Remaining wetland sediment/soil contaminated
with PCBs will be excavated from the wetland until wetland sediment/soil cleanup levels are
achieved and disposed of at an appropriately licensed off-site disposal facility. PCBs found in
groundwater above cleanup levels will be removed by the pump and treat system, separated from
the discharge water, and disposed of off-site at a licensed facility. Consistent with Section
761.61(c) of TSCA, EPA has determined that the management and disposal of PCB
contaminated material as described in the Administrative Record for this cleanup plan does not
result in an unreasonable risk of injury to human health or the environment as long as certain
conditions are met (see Appendix E).

3. The Selected Remedy is Cost-Effective

In EPA's judgment, the selected remedy is cost-effective because the remedy's costs are
proportional to its overall effectiveness (see 40 C.F.R. 300.430(f)(l)(ii)(D)). This determination
was made by evaluating the overall effectiveness of those alternatives that satisfied the threshold
criteria {i.e., that are protective of human health and the environment and comply with all federal
and any more stringent state ARARs, or as appropriate, waive ARARs). Overall effectiveness
was evaluated by assessing three of the five balancing criteria - long-term effectiveness and
permanence; reduction in toxicity, mobility, and volume through treatment; and short-term
effectiveness, in combination. The overall effectiveness of each alternative then was compared
to the alternative's costs to determine cost-effectiveness. The relationship of the overall
effectiveness of this remedial alternative was determined to be proportional to its costs and hence
represents a reasonable value for the money to be spent.

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The selected remedy is more cost-effective than the other active alternatives considered. The
active combined soil, NAPL wetland sediment/soil and groundwater alternatives range in cost
from $0 to $54.4 million. The range in estimated cost for the four soil alternatives for the
Whitney, Murphy and Abeijona Properties is $0 (SW-1: No-Action) to $9.8 million (SW4), $0
(SM-1: No Action) to $11.4 million (SM-4) and $0 (SA-1: No Action) to $0.63 million (SA-4),
respectively. The range for the three NAPL alternatives is $0 (N-l: No Action) to $3.4 million
(N-3) and the range for the five wetland sediment/soil alternatives is $0 (WTL-1: No Action) to
$2.2 million (WTL-5). The range for the six groundwater alternatives is from $0.0 (GW-1: No
Action) to $27.0 million (GW-5).

Off-site transport and disposal is an expensive component of the source control alternatives,
making soil alternatives SW-4/SM-4/SA-4, NAPL alternative N-3 and Murphy Wetland
alternative WTL-5 the most expensive because they require the greatest volume of off-site
disposal. Soil Alternatives SW-4/SM-4/SA-4 are $0.22 million to $8.4 million more than the
selected SW-3/SM-3/SA-3 remedies. The selected N-3 Alternative is $2.6 million more
expensive than the other active NAPL remedy (N-2). The selected WTL-5 Alternative for
Murphy Wetland sediments/soil is $1.2 million more than the capping alternative (WTL-3) and
$0.3 million more than the targeted excavation alternative (WTL-4).

Although soil Alternatives SW-3/SM-3/SA-3 are comparable to SW-4/SM-4/SA-4 in that these
alternatives will both provide a high degree of long-term effectiveness and permanence through
soil removal and capping, the SW-4/SM-4/SA-4 Alternatives are more expensive because they
involve the excavation and off-site disposal of an additional approximately 31,000 cubic yards of
impacted soil. In addition, the SW-4/SM-4/SA-4 alternatives would be more difficult to
implement due to the need to excavate, truck and import greater amounts of material and remove
greater portions of the existing buildings, resulting in a prolonged disruption to property owners
and greater potential for accidents.

Alternatives SW-2/SM-2/SA-2 involves capping and Institutional Controls and are the least
expensive alternatives other than no action; however, these alternatives will leave behind
significantly contaminated soils in the saturated zone which will continue to impact groundwater
and the wetland. Alternatives SW-2/SM-2/SA-2 include minimal soil disturbance and no soils
are transported off-site (e.g., less truck traffic, etc.), protecting the community and workers
performing the cleanup the most in the short term; however, the SW-2/SM-2/SA-2 may present
significant challenges for complying with ARARs, including TSCA, federal and State wetland
protection standards; and 44 C.F.R. Part 9, Floodplain Management and Protection of Wetlands,
in particular flood storage requirements.

Alternative N-3 is more expensive than the NAPL skimming alternative (N-2) because it
involves the excavation and disposal of approximately 6,000 cubic yards of NAPL-contaminated
soil from the Murphy and Whitney Properties; however, Alternative N-3 is expected to have the
best long-term effectiveness and permanence because the free-draining and residual NAPL will
be excavated and disposed off-site. The N-3 Alternative will achieve RAOs in the shortest period
of time since NAPL will be excavated and no longer serve as a source of contamination to soil,

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groundwater, and the wetland. However, Alternative N-3 may be associated with greater short-
term risks to workers performing the cleanup than Alternative N-2 due to the required handling
of NAPL-impacted materials and more disruption to property owners.

For the Murphy Wetland sediments/soil, Alternative WTL-5 is marginally more expensive than
Alternatives WTL-4 because it involves the excavation and disposal of an additional
approximately 3,300 cubic yards of impacted wetland sediment/soil; however, the long-term
effectiveness and permanence of the WTL-5 alternatives is the highest and no cap or Institutional
Controls will be required to manage residually impacted sediment.

Although it is the least expensive alternative, other than No Action, Alternative WTL-2 would
not achieve cleanup standards within a reasonable time period compared with the
capping/excavation scenarios. Alternative WTL-3 is also less costly than WTL-5; however, it
would result in significant filling of wetlands and loss of flood storage capacity with no
identified practicable area within the watershed, upstream of sensitive flood receptors, to create
replacement wetland/flood storage. In addition, significantly contaminated sediment would
remain in place as part of the WTL-3 Alternative. It may be difficult for this alternative to
comply with ARARs since areas for wetland and flood storage mitigation within the watershed
are extremely limited.

Table K-l helps demonstrate the cost-effectiveness of the selected soil, NAPL and wetland
sediment/soil remedies.

For groundwater, the selected management of migration remedy, GW-6, costs $4.2 million. The
GW-4, GW-5 and GW-6 Alternatives are more expensive than the GW-2 (Institutional Controls)
and GW-3 (MNA and Institutional Controls) because in addition to Institutional Controls and
monitoring, they include active remedial measures.

Alternatives GW-4, GW-5, and GW-6 are all expected to have good long-term effectiveness due
to the combination of temporary Institutional Controls and active treatment. Alternative GW-5
includes In-Situ Chemical Oxidation and Institutional Controls and is the most expensive by
$22.8 million because it includes a pre-design investigation, bench scale testing, pilot testing and
the installation of several hundred injection points/wells that will be subject to three rounds of
injection. Although the GW-4 Alternative {In-Situ Bioremediation and Institutional Controls)
also involves aquifer injection activities, this alternative is less expensive as it involves only two
rounds of injection. GW-6 includes groundwater extraction and treatment for SWP-wide
groundwater and is the less expensive than GW-4 and GW-5 by $2.9 million and $22.8 million,
respectively. Alternative GW-6 requires fewer wells than Alternatives GW-4 or GW-5 and is
anticipated to have the greatest reduction of toxicity, mobility or volume through treatment. The
GW-6 Alternative is also likely to achieve groundwater PRGs more quickly than the other
alternatives and to provide containment of the groundwater contamination until cleanup levels
are achieved.

See Table K-l for the estimated costs for each groundwater alternative.

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4.	The Selected Remedy Utilizes Permanent Solutions and Alternative Treatment or
Resource Recovery Technologies to the Maximum Extent Practicable

Once the Agency identified those alternatives that attain or, as appropriate, waive ARARs and
that are protective of human health and the environment, EPA identified which alternative
utilized permanent solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable. This determination was made by deciding
which one of the identified alternatives provides the best balance of trade-offs among
alternatives in terms of: 1) long-term effectiveness and permanence; 2) reduction of toxicity,
mobility or volume through treatment; 3) short-term effectiveness; 4) implementability; and 5)
cost. The balancing test emphasized long-term effectiveness and permanence and the reduction
of toxicity, mobility and volume through treatment; and considered the preference for treatment
as a principal element, the bias against off-site land disposal of untreated waste, and community
and state acceptance. The selected remedy provides the best balance of trade-offs among the
alternatives.

The selected remedy is protective of human health and the environment, uses proven cleanup
technologies such as excavation, treatment and disposal, and is cost effective, while achieving
the site-specific cleanup objectives in a reasonable timeframe. This cleanup approach provides
both short and long-term protection of human health and the environment; attains all applicable
or relevant and appropriate federal and state environmental laws and regulations; reduces the
toxicity, mobility, and volume of contaminated soil, sediment, and groundwater through
treatment, to the maximum extent practicable; utilizes permanent solutions and uses land use
restrictions to prevent unacceptable exposures in the future to the contaminants that will remain
at the SWP.

Table K-l demonstrates how the respective selected remedies provide the best balance of trade-
offs when compared against the evaluation criteria.

5.	The Selected Remedy Partially Satisfies the Preference for Treatment as a Principal
Element

The principal elements of the selected remedy are source control and management of migration.
These elements address the primary threats at the SWP, contamination within the Northern
Whitney Soil Area and the Murphy Property NAPL area, that contain principal threat waste at
levels that represent a greater than 10"3 risk, and present a source for contamination of
groundwater. The selected remedy will permanently remove the Principal Threat Wastes from
the SWP and dispose of it off-site at facilities licensed to accept the waste untreated, but does not
achieve the statutory preference of treatment for these wastes. Full scale implementation of
treatment for the large volume of excavated SWP soils, NAPL and wetland sediments/soils
(approximately 30,800 cubic yards) is impracticable. Given technology and space, no practicable
means of on-site treatment was identified except for potential measures to add stabilizing agents
to the waste prior to shipment to facilitate waste transport and meeting off-site disposal facility

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requirements. However, the selected remedy will backfill the NAPL and deeper soil excavations
with an amendment to provide localized soil and groundwater treatment, and dewatering
activities associated with implementing the soils, sediments and NAPL work will provide
treatment of water prior to discharge. In addition, the selected remedy for Groundwater will
satisfy the statutory preference for treatment. Thus, the overall selected remedy partially
satisfies the statutory preference for treatment as a principal element of the remedy.

6. Five-Year Reviews of the Selected Remedy are Required

At the conclusion of the remedy construction, hazardous substances, pollutants or contaminants
will remain at the SWP, as is also the case at other Operable Units within the Wells G&H Site.
Therefore, as required by law, EPA will review the SWP remedy to assure that the remedial
action continues to protect human health and the environment at least once every five years as
part of the Agency's five-year reviews for the entire Site. These five-year reviews will evaluate
the components of the SWP remedy for as long as contaminated media above CERCLA risk
levels remain in place. The next Well G&H Site five-year review (the fifth) is due in 2019.

N. DOCUMENTATION OF NO SIGNIFICANT CHANGES

EPA presented a proposed plan for remediation of the SWP on July 13, 2017. The major
components of the preferred alternative included:

•	Excavation and off-site disposal of approximately 5,400 cubic yards of significantly
contaminated soil at the designated Northern Whitney Soil Area, and blending remaining
contaminated soil below the water table with an amendment prior to backfilling to
provide soil and localized groundwater treatment. In addition, excavation and off-site
disposal of approximately 12,400 cubic yards of soil to facilitate capping and maintain
flood storage, and construction of impermeable caps over the remaining lower
concentration soils that exceed cleanup levels to reduce soil exposure risks and/or prevent
contaminant movement to groundwater;

•	Excavation and off-site disposal of NAPL, including approximately 6,000 cubic yards of
NAPL-contaminated soil and the blending any remaining NAPL-contaminated soil below
the water table with an amendment prior to backfilling to provide soil and localized
groundwater treatment;

•	Containment and cleanup of groundwater contaminants by pumping and treating the
groundwater;

•	Excavation and off-site disposal of approximately 7,000 cubic yards of wetland
sediment/soil exceeding cleanup levels and wetland restoration;

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• Long-term monitoring; and

• Institutional Controls to maintain the integrity of the soil caps and other remedial
components; to prevent development of the properties for residential, school, and daycare
use; to prohibit use of contaminated groundwater until cleanup levels are met; and to
require evaluation of the vapor intrusion pathway if a change in usage of any of the
existing buildings is contemplated or as part of new building construction, including any
addition/alteration to existing buildings on any of the properties.

EPA reviewed all written and verbal comments submitted during the public comment period. It
was determined that no significant changes to the remedy, as originally identified in the proposed
plan, were necessary.

O. STATE ROLE

The Massachusetts Department of Environmental Protection has reviewed the various
alternatives and has indicated its support for the selected remedy. The Commonwealth has also
reviewed the Remedial Investigation, Risk Assessments, Feasibility Study, and FS Report
Addendum to determine if the selected remedy is in compliance with applicable or relevant and
appropriate state environmental and facility siting laws and regulations. The Commonwealth of
Massachusetts concurs with the selected remedy for the SWP, OU-4 of the Wells G&H
Superfund Site. A copy of the declaration of concurrence is attached as Appendix A.

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PART 3 - THE RESPONSIVENESS SUMMARY FOR THE
RECORD OF DECISION

A. PUBLIC COMMENTS AND EPA RESPONSES

On July 6, 2017, EPA mailed notice of the Proposed Plan to interested parties. On July 11, 2017,
notice of the Proposed Plan was published on EPA's web page. On July 12, 2017, EPA issued a
press release announcing the Proposed Plan, and on July 14, 2017, EPA published a notice of the
availability of the Proposed Plan in the Woburn Daily Times and Boston Globe newspaper. On
July 13, 2017, EPA made the administrative record and the Agency's Proposed Plan available for
public review at EPA's offices in Boston and at Woburn Public Library. On July 13, 2017, EPA
also held an informational meeting at Woburn City Hall, City Council Chambers, 10 Common
Street, Woburn, MA. From July 14, 2017 to August 14, 2017, EPA held a 30-day public
comment period to accept public comment on the alternatives presented in the 2017 Feasibility
Study Report Addendum - Technical Memorandum, 2016 Feasibility Study Report, and the
Proposed Plan and on any other documents previously released to the public. An extension to
the public comment period was requested, and the comment period was extended to September
13, 2017. On August 3, 2017, the Agency held a public hearing at Woburn City Hall, City
Council Chambers, 10 Common Street, Woburn, MA, to discuss the Proposed Plan and to accept
any oral comments. A transcript of this meeting and the comments and the Agency's response to
comments are included below. Outlined below is a summary of comments received from the
public and other interested parties during the public comment period and EPA's response to those
comments. Similar comments have been summarized and grouped together. The full text of all
written and oral comments received during the comment period has been included in the
Administrative Record.

Summary of comments received via email from AECOM on 9/12/17 representing the
Beatrice Company:

Proposed Plan

AECOM Comment 1:

EPA's Proposed Cleanup Approach, Groundwater (Pg. 7, last paragraph and Pg. 23, GW-
6 Pump and Treat and Institutional Controls (EPA's Preferred Alternative)):

EPA recommends that "pre-design investigation activities may include consideration of upgrades
to the adjacent Wildwood Source Area Property groundwater treatment system plant to
accommodate and adequately treat extracted groundwater from the SWP in lieu of constructing a

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groundwater treatment plant on the SWP". The Wildwood treatment system was designed for
groundwater remediation at the Wildwood Property. Given the age of the system and potential
liability issues with treatment of groundwater sourced from other properties, it is not considered
appropriate to contemplate potential future SWP groundwater treatment at the Wildwood Source
Area Property.

EPA Response: While EPA acknowledges the Commenter's concerns about the potential use of
the Wildwood Source Area Property (Wildwood SAP) groundwater remediation system for the
OU4 remedy, EPA has retained its use as an option in the ROD to maintain remedy flexibility.
The issues raised by the Commenter would be addressed at the remedialpre-design phase, in the
event the use of the Wildwood SAP groundwater remediation system is retained as a treatment
option. As the ROD describes, the SWP, Operable Unit 4, pre-design investigations activities
may include consideration of upgrades to the adjacent Wildwood SAP groundwater remediation
system to accommodate and adequately treat extracted groundwater from the SWP in lieu of
constructing a groundwater treatment plant on the SWP. As part of this process, the pre-design
investigation activities will consider the age of the adjacent Wildwood SAP groundwater
remediation system and any necessary upgrades to adequately treat extracted groundwater from
the SWP (while continuing to treat extracted water from the Wildwood SAP).

AECOM Comment 2:

Background Section, Murphy Wetland (Pg. 13):

The data presented in the RI and FS do not support EPA's comments that the Wildwood Property
to the north is a likely source of impacts to the Murphy Wetland (e.g., due to the mixed-
contaminated soil impacts that were remediated in 1993-1994). In their FS Report Addendum -
Technical Memorandum (July 2017), EPA states that one area at the Wildwood Property near the
northwest portion of the wetland (Area 4 identified in the 100-Percent Design Report, Mixed
Contaminated Soils [RETEC, 1994]) represents a potential source of impacts to wetland
sediments and soils because of the potential for pre-remediation surface erosion and periodic
flooding events. The rationale provided by EPA for former soils in Area 4 at Wildwood as a
potential contributor of wetland impacts is not supported by the data collected in the wetlands. In
summary, EPA identified the location of Area 4 as adjacent to the northwest corner of the
wetland. Former Area 4 was adjacent to the northeast corner of the wetland, on the east side of
the Wildwood Property access road, and was hydraulically downflow from the Murphy Wetland.
Former Area 4 was approximately 400 square feet in area and 30 cubic yards of soil was
excavated in the early 1990s. Pre-design sampling results had a maximum PCB concentration of
25 mg/kg and a maximum lead concentration of 683 mg/kg in Area 4. Sediment data collected
from the far eastern portion of the Murphy Wetland, closest to Former Area 4, had chromium,
lead, and zinc results that were less than the lowest PRGs.

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EPA Response: EPA agrees that the location of Area 4 is to the "northeast" of the Murphy
Wetland and not to the "northwest" of the Murphy Wetland. EPA disagrees with the
Commenter 's suggestion that data collected in the wetlands does not support EPA 's statements
in the 2017 FS Report Addendum. For example, the 2016 RI Report Figure 4-53 illustrates PCB
concentrations in the wetland, including north/northeast samples P-33 (PCBs at 7.9 mg/kg) and
P-24A (PCBs at 4.9 mg/kg), which exceeds the ROD's cleanup standardfor PCBs in wetland
soils/sediments. EPA 's statement in the FS Report Addendum is further supported by RI Report,
Section 6.2 Primary and Secondary Transport Mechanisms, 6.2.4 Physical Processes, which
states: "Contaminants in soils can be moved directly via the movement and placement of soils.
Overlandflow that may occur during flooding may suspend soils or sediment and create a re-
distribution of these materials and the associated contaminants. Runoff and erosion processes
occurring during weather events, such as rain or wind, may move surficial soils and associated
contaminants overland towards lower areas (e.g., the Murphy Wetland). From these processes,
soils and sediments not directly part of the operations or release areas may be impacted. " (RI, p.
6-4)

The following is the correct text that replaces the errant text in Section 1.3.4 of the FS Report
Addendum:

"Feasibility Study — Section 1.3.4— Wetland Sediment/Soil

As described in the 100-Percent Design Report, Mixed-Contaminated Soils (RETEC, 1994),
excavation and remediation of mixed-contaminated soils targetedfour distinct areas, including
one area (i.e., "Area 4") located near the southern limit of the Wildwood Property and adjacent
to the northeast portion of the wetland. "

AECOM Comment 3:

Page 9, 3rd bullet:

This bullet discusses site preparation and dewatering and at the end of the bullet states "... water
treatment through a temporary de-watering and treatment system; and discharge to the Abeijona
River". Change the last portion of this statement to ".. .and discharge to the Abeijona River or
other permitted discharge". Justification: This change will allow the flexibility to evaluate other
discharge options, such as to the Publicly Owned Treatment Works, which may be more cost-
effective.

EPA Response: EPA agrees with the Commenter that flexibility is desirable with respect to
discharge options and has provided greater flexibility in the ROD with respect to dewatering
treatment and discharge options for the Soil, NAPL, and Wetland Sediments/Soils components of
the ROD remedy. Specifically, the ROD states: "... water treatment through a temporary de-
watering and treatment system; and discharge to the Aberjona River or appropriate approved
POTW, or disposal at an appropriate off-site permitted disposal facility, or appropriate

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approved on-site treatment and discharge from adjacent Operable Unit-1 source area property
(Wildwood Source Area Property);" (ROD, Section L)

AECOM Comment 4:

Page 9, 4th bullet:

Revise this bullet as follows: Add "Excavate to a maximum of three feet. If contaminants are
present above the remediation goals deeper than 3 feet, they will be effectively isolated by
placement of a three foot cover. Excavation may be terminated at 2 feet if the remaining
sediments are not significantly impacted (less than 10X the remedial goals). These sediments
with minimal impacts will be effectively isolated by a two foot cover." Delete "Perform
confirmation sampling to demonstrate compliance with cleanup levels." Substitute the following:
"The approach to verifying that the cleanup objectives are met will be determined by the design
engineer as part of the remedial design. Acceptable options include pre-excavation delineation
and excavation to target elevation without pit bottom samples, excavation and pit bottom
samples, or a combination of these approaches. Achieving the numerical goals is not required in
areas where the three foot cover is being installed. The two or three foot cover will effectively
isolate any residual impacts to sediments." Justification: The remedial goals selected by EPA are
very low and may be similar to background conditions. The above changes are necessary to
prevent additional deeper excavation and associated higher remedy costs. Limiting the
excavation depth to a maximum of three feet is protective of potential receptors because a three
foot cover will be installed, effectively isolating any residual impacts. In a similar way, stopping
at 2 feet may be appropriate where the residual levels of contamination are relatively low (less
than 1 OX goals).

EPA Response: EPA does not agree with the Commenter's approach for the Murphy Wetland.
EPA 's selected remedy removes all contamination above remediation goals so that no long-term
monitoring, institutional controls, or five-year reviews are requiredfor the Murphy Wetland.
There is no defined depth of excavation, because depth of excavation is solely driven by the
presence of contaminated wetland soil/sediment exceeding the remediation goals, so excavations
in some areas may be less than three feet. Under the Commenter's proposal to use pre-defined
depths of excavation, confirmatory sampling would be needed to determine if subsurface
contamination above remediation goals is being left in place requiring a cap/cover, long-term
monitoring, institutional controls andfive-year reviews. Whether a soil/sediment cover or
engineered cap needs to be installed depends on what contaminants are left behind and at what
contaminant levels. In particular, if PCBs exceeding TSCA thresholds are left in place in the
subsurface below the maximum excavation depth, then a TSCA-compliant cap would be
required. The comment also relies on cover/cap integrity to maintain protectiveness, which
would necessitate long-term costs for monitoring and maintenance.

The selected remedy will include wetland sediment/soilpre-design sampling to more accurately
determine the extent of sediment contamination exceeding remediation goals, remove all wetland

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sediment/soil above remediation goals, and provide the higher degree of Long-Term
Effectiveness and Permanence. The selected remedy will also include post excavation sampling
to confirm the remediation goals have been achieved and ARARs have been satisfactorily met.
While the Commenter claims the remediation goals "may be similar to background conditions ",
the remediation goals for the wetland sediment/soil selected remedy were established at or above
background conditions, as is required under CERCLA.

AECOM Comment 5:

Page 9, 4th bullet:

Requiring post excavation confirmation samples unnecessarily restricts the design process and
causes delays during construction. Post-excavation sampling requires the excavation to be left
open for at least one day to typically several days. During that period the excavation fills back up
with water and thus added costs are incurred due to delays and additional dewatering.

Conducting pre-excavation delineation sampling and then excavating to the target depth without
post-excavation sampling is an accepted practice that reduces delays and reduces costs.

EPA Response: Post excavation confirmation sampling will demonstrate that all of the wetland
sediment/soil above the remediation goals have been adequately removed and that the remedy
complies with ARARs and removes all contaminants exceeding risk standards from the Murphy
Wetland. Dewatering is a component of the wetland sediment/soil remedy, which is typically
accomplished with one mobilization and demobilization. The timing concerns the Commenter
expresses in the comment will be addressed during remedial design through efficient sequence
planning for wetland sediment/soil excavation and confirmatory sampling. These measures will
be used to reduce costs and prevent project delays.

AECOM Comment 6:

Page 9, Paragraph after 8th (last) bullet:

Change "Alternative WTL-5 includes excavation to remove all wetland sediment/soil with
contaminants in excess of the wetland sediment/soil cleanup levels. Deeper or shallower
excavations may be conducted in specific areas of the wetland, depending on pre-design
sampling results. Confirmation sampling will be performed to demonstrate compliance with
excavation goals. Alternative WTL-5 includes backfilling the excavation to pre-remediation
grades and includes restoration of the floodplain/wetland habitat." To: "Alternative WTL-5
includes excavation to remove wetland sediment/soil with contaminants in excess of the wetland
sediment/soil cleanup levels. Shallower excavations may be conducted in specific areas of the
wetland, depending on pre-design sampling results. Sediment/soil with residual levels of
contaminants (less than 10X the goals) may remain in place but would be covered with a
minimum of two feet of cover. Alternative WTL-5 includes backfilling the excavation to pre-
remediation grades and includes restoration of the floodplain/wetland habitat." Justification: The

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maximum excavation depth should be three feet. Escalating remedy costs for deeper excavation
would not provide any significant risk reduction.

EPA Response: See above responses to AECOM Comments 4 and 5.

AECOM Comment 7:

Page 9, last paragraph:

EPA states "Plantings and visible ground surfaces will be inspected and maintained as required
by the restoration plan and ARARs requirements. The monitoring period is assumed to be at least
three years." Delete the sentence "The monitoring period is assumed to be at least three years."
and replace it with "Monitoring will continue until the new wetland vegetation has been
established as described in a wetland planting plan. A two year monitoring period is anticipated."
Justification: This change will allow greater flexibility to effectively and efficiently monitor the
wetlands restoration and control costs that may be unnecessary.

EPA Response: The language proposed by the Commenter does not follow federal wetland
mitigation practice in the 2016 US Army Corps of Engineers New England District
Compensatory Mitigation Guidance (Corps Mitigation Guidance), which addresses
restoration/mitigation under Section 404 of the federal Clean Water Act and its supporting
regulations. As described in the Corps Mitigation Guidance, the monitoring of the wetland
restoration/mitigation in the shrub/scrub wetland habitat to be altered by the remedial action or
where invasive species need to be controlled would typically be conducted, at a minimum, during
post-construction years 1, 2, 3, 5, 7, and 10, with maintenance conducted as needed. The
specific schedule for the OU4 remedy will be developed as part of the remedial design process,
but is expected to follow the Corps Mitigation Guidance standards.

AECOM Comment 8:

Page 16, first full paragraph:

The Proposed Plan presumes that the SWP is a potential future drinking water source. However,
if the SWP is a Potential Productive Aquifer (PPA) as mapped by MassGIS and not a drinking
water source area as stated in the Proposed Plan, then it is prudent to consider whether the SWP
should more appropriately have a Non-Potential Drinking Water Source Area (NPDWSA)
designation. Based upon an initial review of the policy considering land use, the SWP may
qualify as a NPDWSA. This analysis should be completed in accordance with MassDEP Policy
WSC-97-701 (Determining NPDWSAs, dated April 4, 1997) and submitted to MassDEP for
final determination. Furthermore, MassDEP is considering regulatory changes (Massachusetts
Contingency Plan, 310 CMR 40.0000) regarding the 100-acre criteria defining a NPDWSA that
may make this option more feasible for the SWP to meet. If the SWP can be classified as an

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NPDWSA, then the proposed groundwater cleanup levels should be modified accordingly. The
Proposed Plan should include language contemplating this alternative designation.

EPA Response: In June 2004, MassDEP prepared a Use and Value Determination for the
aquifer at the Wells G&H Superfund Site (see the Administrative Record). Under the Use and
Value Determination, the State has rated the aquifer with a "Medium " groundwater use and
value determination, because of its significant current andfuture ecological value to the
Aberjona River and associated wetlands, and its potential value as a drinking water supply in the
future. It also falls within an Interim Wellhead Protection Area. Based upon this determination,
future potable use of SWP-wide groundwater by a resident is possible. Because of the Use and
Value Determination, the baseline risk assessment needed to consider exposure scenarios for the
groundwater risk evaluation, including, but not limited to: ingestion and exposures from other
domestic uses; inhalation of vapors from seepage into buildings; use of the water in industrial
processes and other potential exposures to the use of the water in industrial and residential
activities; worker exposure during excavation into groundwater; and exposures resulting from
discharge to surface water. " In March 2014, EPA, in consultation with MassDEP, prepared a
human health and ecological baseline risk assessment for the Southwest Properties (see
Administrative Record), which included exposure to groundwater through ingestion, vapor
intrusion, construction work, etc., consistent with the MassDEP June 2004 Use and Value
Determination. The State supports EPA's remedy to restore the aquifer to drinking water
standards (see Appendix A).

FS Report Addendum

AECOM Comment 9:

Page 2, Remedy Implementation Section: EPA clarifies they expect pre-design investigations
(PDI) for groundwater to occur in parallel with PDI for soil and NAPL remedies such that the
"groundwater remedy design will overlap with the design and implementation of the soil and
NAPL remedies to avoid unnecessary delays with constructing the selected groundwater
alternative. EPA expects that construction/implementation of the selected groundwater remedy
will commence once the selected NAPL remedy and the selected soil remedy involving the
Northern Whitney Soil Area have been implemented." This statement unnecessarily restrains the
design engineer and is likely to lead to a poor overall design. There is no technical basis to
proceed with design of the groundwater remedy before the benefits of source removal are
realized. A more technically sound approach would be to wait 2 to 5 years to better evaluate the
effect of soil removal and backfill amendment on remaining groundwater concentrations prior to
designing and implementing a groundwater remedy. Designing the pump and treat system before
source removal will likely lead to over-design both in terms of the treatment processes and
number of extraction wells. As conceptually designed in the FS, the soil excavations down into
and below the water table and placement of treatment amendments is a highly effective
groundwater remedy. These actions alone will improve groundwater in the local area and,

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overtime, in a broader area. Designing and implementing a groundwater pump and treat system
before the benefits of source removal are realized is premature. Considering that the groundwater
is not currently being used in the area and that there is no evidence that the plume is spreading,
monitoring for a set period of time to inform the design and build of the pump and treat system is
protective of receptors and recommended.

EPA Response: EPA disagrees with the comment. The selected remedy's use of amendments
will not eliminate shallow groundwater contamination where the amendments are applied, and
implementation of the selected remedy is necessary to address the remaining contamination in
shallow groundwater as well as the deeper groundwater (e.g. intermediate and bedrock
groundwater; see 2016 RIReport Figures 3-5 andFS Report Figure 1-7). As noted in the 2016
FS Report, implementation of the soil selected remedy at the Northern Whitney Soil Area (e.g.
excavation, backfilling with a ZVI amendment, and placement of a cap) would reduce 90% of the
PCB and CVOC contamination in the shallow groundwater (2016 FS Report, p. 5-12). The
Northern Whitney Soil Area contains some of the highest PCB and CVOC soil concentrations on
the SWP, however, and the remaining 10% of soil contamination would continue to impact
groundwater. The soil and NAPL components of the remedy will only directly alter contaminant
levels in the shallow groundwater, leaving deeper contamination unaddressed.

The 2016 FS Report, Figure 1-7 Overview ofSWP-Wide Groundwater Impacts, illustrates that
the shallow and intermediate overburden groundwater zones and the bedrock zones are
impacted with contamination requiring groundwater treatment. As illustrated in the 2016 RI
Report Figure 3-5, "Geologic Cross Section B-B' and Groundwater Elevation Data "from April
2011, the saturated thickness of the overburden under the southwest properties ranges from 75'
to 130', where the shallow overburden zone saturated thickness is 0' - 25' and the intermediate
overburden zone saturated thickness is from 25' - 130'. As described in the 2017 FS Report
Addendum (p. 20, 215 & 222 of472, "the soil amendment is focused on reducing VOC
concentrations in soil and shallow groundwater, " and "the saturated thickness of the shallow
overburden zone of the aquifer is estimated to be about 25 feet. " The soil amendment is only
being applied to backfill soils in limited areas of the shallow zone (e.g. Northern Whitney Soil
Area, and NAPL areas on the Murphy and Whitney Properties, as described the FS Report
Addendum and illustrated on Figure 5-2, 5-5 & 5-8 and Figure 5-14), and the contaminated
shallow groundwater below and outside of these areas of amendment backfill are not anticipated
to be reduced. In addition, the impacted groundwater within the larger intermediate overburden
zone saturated thickness (25' - 130') and the saturated bedrock zone will not be reduced.

Regarding the sequencing of the remedial components, the timing of the remedial work will be
finalized as part of the remedial design but it is expected that construction/implementation of the
groundwater remedy will commence once the selected NAPL remedy and soil remedy involving
the Northern Whitney Soil Area have been implemented. The timing of these measures will
address contaminated groundwater throughout the SWP to achieve groundwater cleanup within
the estimated 20 years described within the 2017 FS Report Addendum.

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AECOM Comment 10:

Page 4, Remedy Implementation Section: EPA is requesting that the amendment be selected to
treat all VOCs detected in groundwater, both chlorinated and non-chlorinated. This is a restraint
on the design engineer and is likely to lead to a less than optimal amendment selection. Non-
chlorinated VOC impacts are relatively minor compared to the chlorinated volatile organics
(CVOCs) and should continue to degrade naturally. The best treatment reagents for CVOCs are
not the same as for non-chlorinated VOCs. In fact, reagents selected for non-chlorinated VOCs
can make the CVOC problems worse. The following statement is recommended: "The
amendment selection will be determined by the design engineer with a focus on treatment of
CVOCs. Simultaneous treatment of non-chlorinated VOCs is desirable but not required."

EPA Response: The Remedial Design process will determine the best amendment(s) to be used
to treat contamination left in place in the subsurface soils. As expressed in the Proposed Plan
and further expressed in the ROD, the Remedial Design for the selected NAPL remedy and
selected soil remedy involving the Northern Whitney Soil Area will include bench-scale testing of
soil amendments (e.g. ZVI) for backfill to treat and mitigate localized soil and groundwater
contamination. Considering the significant CVOCs concentrations present at the Northern
Whitney Soil Area, soil amendments for backfill to treat and mitigate localized soil and
groundwater contamination will emphasize reducing chlorinated VOCs.

AECOM Comment 11:

General Clarifications Section, Potential Contribution of Groundwater Impacts to
Northeast Corner of SWP from the Adjacent Wildwood Property (Pg. 6):

• EPA believes impacted groundwater originating at Wildwood "could be a past and ongoing
contributor of impact to groundwater at the northeast corner of the SWP in the vicinity of the
S77 well cluster." The selected alternative in the proposed plan (GW-6) does not include
treatment of groundwater from the S77 well cluster area located on the southern portion of
Wildwood OU-1 property; therefore, any groundwater treatment that may be required in this area
is separate from the groundwater alternative presented in the SWP Proposed Plan.

EPA Response: EPA agrees with the Commenter that the selected alternative does not address
contaminated groundwater in the vicinity of the S77 well cluster. The selected remedy addresses
groundwater contamination in the area illustrated on Figure 1-7 of the 2016 RI Report within
OU4. The S77 well cluster is located in OU1 and any groundwater contamination in that area
will be addressed by the OU1 remedy.

AECOM Comment 12:

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Section-Specific Clarifications Section, Feasibility Study - Section 1.3.4 - Wetland
Sediment/Soil (Pg. 8): The data presented in the RI and FS do not support EPA's comments that
the Wildwood Property to the north is a likely source of impacts to the Murphy Wetland (e.g.,
due to the mixed-contaminated soil impacts that were remediated in 1993-1994). In their FS
Report Addendum - Technical Memorandum (July 2017), EPA states that one area at the
Wildwood Property near the northwest portion of the wetland (Area 4 identified in the 100-
Percent Design Report, Mixed Contaminated Soils [RETEC, 1994]) represents a potential source
of impacts to wetland sediments and soils because of the potential for pre-remediation surface
erosion and periodic flooding events. The rationale provided by EPA for former soils in Area 4
at Wildwood as a potential contributor of wetland impacts is not supported by the data collected
in the wetlands. In summary, EPA identified the location of Area 4 as adjacent to the northwest
corner of the wetland. Former Area 4 was adjacent to the northeast corner of the wetland, on the
east side of the Wildwood Property access road, and was hydraulically downflow from the
Murphy Wetland. Former Area 4 was approximately 400 square feet in area and 30 cubic yards
of soil was excavated in the early 1990s. Pre-design sampling results had a maximum PCB
concentration of 25 mg/kg and a maximum lead concentration of 683 mg/kg in Area 4. Sediment
data collected from the far eastern portion of the Murphy Wetland, closest to Former Area 4, had
chromium, lead, and zinc results that were less than the lowest PRGs.

EPA Response: See above response to AECOM Comment 2.

AECOM Comment 13:

Section-Specific Clarifications Section, Alternative GW-6: Pump and Treat with
Institutional Controls, Subsection a). (Pg. 36): EPA states that "Alternative GW-6 shall also
consider potential coordination with the adjacent Wildwood Property for upgrading their existing
groundwater treatment system to potentially receive GW-6 contaminated groundwater extracted
from the SWP for treatment." The Wildwood treatment system was designed for groundwater
remediation at the Wildwood Property. Given the age of the system and potential liability issues
with treatment of groundwater sourced from other properties, it is not considered appropriate to
contemplate potential future SWP groundwater treatment at the Wildwood Source Area Property.
Furthermore, considering the Proposed Plan ill-advisedly contemplates designing the
groundwater remedy prior to evaluating the benefits from source removal and/or remedial
amendment placement below the water table, this suggestion exacerbates the risk of over-design
of the contemplated upgrades to the Wildwood treatment system, rendering this option
impractical, infeasible, and arbitrary.

EPA Response: See above response to AECOM Comment 1.

AECOM Comment 14:

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Section-Specific Clarifications Section, Alternative WTL-5: Deep (3 ft) Excavation and Off-
Site Disposal, Backfill, and Wetland Restoration, Subsection a). (Pg. 42):

• EPA states that all sediment/soil above the PRGs will be removed. This is an unnecessary
requirement because a three foot cap is being installed. The PRGs are very low and in many
cases near background levels. Escalating remedy costs for deeper excavation below 3 feet would
not provide any significant risk reduction.

EPA Response: See above response to AECOM Comment 4.

AECOM Comment 15:

Section-Specific Clarifications Section, Alternative WTL-5: Deep (3 ft) Excavation and Off-
Site Disposal, Backfill, and Wetland Restoration, Subsection a). (Pg. 42):

EPA is requiring confirmation samples but in this context it does not specify if they are pre-
excavation or post-excavation. We suggest they add "(confirmation samples may be collected
before or after excavation)."

EPA Response: EPA clarifies that the confirmation sampling to demonstrate compliance for the
selected remedy refers to post-excavation compliance sampling.

AECOM Comment 16:

Section-Specific Clarifications Section, Alternative WTL-5: Deep (3 ft) Excavation and Off-
Site Disposal, Backfill, and Wetland Restoration, Subsection a). (Pg. 42):

Excavation should be limited to a maximum of three feet unless deeper sediments are
"significantly impacted" (10X remedial goals).

EPA Response: See above responses to AECOM Comments 4 and 5.

Summary of comments received from S&J Property Management delivered by hand

8/17/17

S&J Property Management Comment 1:

Is there funding or some type of payment plan for this project?

EPA Response: In May 2014, EPA notified 16 parties of their potential liability at the Southwest
Properties. Since then, EPA continues to pursue evidence on parties that may have

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liability at the Southwest Properties. The purpose of the notifications and continued pursuit of
potentially liable parties is to ultimately reach a settlement with those parties to implement or
fund the selected remedy at the Southwest Properties.

S&J Property Management Comment 2:

How much is the Whitney [Property] owners responsible for?

EPA Response: The estimated total cost for the selected remedy is $19.1 million. Under
CERCLA there is joint and severable liability, which means that each responsible party is
equally liable for all remedy costs. It is not EPA 's role under CERCLA or the NCP to allocate
the costs of the selected remedy between different responsible parties. Please see above
response to S&G Property Management Comment 1.

S&J Property Management Comment 3:

Can you please give a better time of start and finish? [This property is the sole source of
income at this time for the Whitney family. This project should not be a burden to them, they are
not the people that contaminated the property.]

EPA Response: EPA expects that settlement discussions with potentially responsible parties will
begin in 2018. EPA estimates that 2 years will be required to design the remedy and that an
estimated 1-2 years will be required to construct the remedy. EPA expects to coordinate with the
Settling Parties implementing the remedy and the OU4 landowners to minimize impacts to
existing businesses, to the extent practicable.

S&J Property Management Comment 4:

Will there be loss of use? Whitneys have at this time around 14 tenants that rely on this for the
operation of their business and all employ people with families that rely on this to support their
families. We are talking a lot of good people.

EPA Response: The selected remedy, through the remedial design process, will include a
sequencing plan for implementing the remedy in a manner that minimizes disruptions to ongoing
business operations to the extent practical, including determining whether existing business on
the properties will need to be relocated.

Comments submitted by Loureiro on behalf of 280 Salem Street LLC, by letter dated

9/7/17

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280 Salem Street, LLC Comment 1:

280 Salem Street, LLC has significantly improved the conditions at the properties and
improvements have contributed to the reduction of risks associated with any pre-existing
contamination.

EPA Response: EPA agrees that 280 Salem Street LLC has improved the visual aesthetic
conditions at the property by removing hundreds of junked cars around 2004/2005 and building
the hockey arena in 2008/2009. On May 7, 2004, EPA provided 280 Salem Street LLC with a
letter summarizing the status of the cleanup at the Site and recommendations for moving forward
with construction of the hockey arena. In May 2006, EPA approved 280 Salem Street LLC's Soil
and Groundwater Management Plan, which was implemented during the hockey arena
construction. In addition, EPA approved 280 Salem Street LLC's vapor mitigation barrier
which was voluntarily installed during the hockey arena construction.

280 Salem Street, LLC Comment 2:

In providing these comments, 280 Salem Street, LLC reminds the USEPA that the LLC did
not cause, contribute to, or exacerbate any of the releases of oil or hazardous materials
identified at the properties. All releases identified at the properties occurred decades prior to
the LLC's acquisition of the properties.

EPA Response: See above response to 280 Salem Street, LLC Comment 1.

280 Salem Street, LLC Comment 3:

The former Aberjona Auto Parts property is currently used for several businesses
including automobile repair businesses, a used car sales business and storage for new
vehicles. This area is heavily used throughout the day as automobiles are delivered, repaired,
stored and returned to business patrons. The proposed excavation and cap construction activities
would occur in an area that these businesses use and as such construction would cause significant
business disruption to the property.

EPA Response: The selected remedy, through the remedial design process, will include a
sequencing plan for implementing the remedy in a manner that minimizes disruptions to on-
going business operations, to the extent practical, including determining whether existing
business on the properties will need to be relocated. EPA 'sMay 7, 2004 correspondence to 280
Salem Street LLC also emphasized, "that the implementation of response actions at the Site
(including but not limited to work required to complete any Remedial Investigation/Feasibility
Study and work required to implement any Record of Decision which will be issuedfor the Site)
may interfere with your use of the Property, and may require closure of your operations or a

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part thereof. EPA will, consistent with its responsibilities under applicable law, use reasonable
efforts to minimize any interference with your operations by such entry and response. "

280 Salem Street, LLC Comment 4:

Loureiro acknowledges the presence of soil at concentrations exceeding applicable cleanup
standards [on the former Abeijona Auto Parts property] however we conclude that adequate risk
reduction can be achieved through the maintenance of the existing paved surface and controls on
future development through deed restrictions {i.e., Activity and Use Limitation, AUL).
Maintenance of the existing asphalt surface would both obviate the need for soil excavation and
cap construction thus eliminating the disruption to the auto repair operations, and would provide
the necessary barrier between contaminated soil and those who might become exposed to such
contaminants. Finally, the existing asphalt cap would provide the same reduction in contaminant
migration as the USEPA hopes to achieve with the construction of the proposed cap.

EPA Response: EPA disagrees with the comment. Inspections of the existing pavement on the
Aberjona Property characterized the condition of the pavement as "poor. " (2016 FS Report,
Appendix A). Soils on the Aberjona Property above the water table contain naphthalene, TCE,
C9-C10 aromatics, and C11-C22 aromatics above the leaching-based remediation goals. (FS
Report, Appendix D). In addition, the cap must be designed to: "prevent infiltration of surface
water and leaching of COCs from soil above the water table into groundwater. The cap will be
adequately designed with long-term integrity for seasonal conditions, severe storms andfreeze
thaw conditions, and to satisfy ARARs. Conceptually the cap would include a geotextile layer, a
base layer, a plastic liner and an impermeable top layer such as asphalt. The design would
include a plan for management of stormwater. For example, the design may include catch basins
and outfall pipes to the nearest water body. An inspection and maintenance plan will ensure
continued cap integrity. " (2016 FS Report, p. 5-2 7) Therefore, the existing pavement is in poor
condition, and the selected remedy requires an appropriate design and construction of an
impermeable cap to achieve the remediation goals.

280 Salem Street, LLC Comment 5:

Loureiro and 280 Salem Street, LLC are concerned about the

significant business interruption associated with the installation of the wells and trench/piping
network. The proposed plan describes a network that would extend across the center of the
Aberjona property where a significant number of the automobiles are stored and where
effectively all of the traffic associated with site activities must pass. Loureiro recommends that
any such piping and well installation work be carefully considered and coordinated in a manner
that does not interfere with daily site activities.

EPA Response: See above response to 280 Salem Street, LLC Comment 3.

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280 Salem Street, LLC Comment 6:

Figure 3 of the Proposed Plan depicts the proposed construction of a Treatment Plant to
the northwest of the existing Holland Arena. Recognizing that the Figure indicates that the
location is "to be determined" 280 Salem Street, LLC is opposed to its placement on the arena
property because it is proposed in the location scheduled for an addition to the arena. Holland
Arena has proposed its second phase of development on the parcel with a new building and ice
surface. Placement of the Treatment Plant is not compatible with and will interfere with the
expansion of the arena facility which is planned for the spring of 2018. Loureiro suggests
that it would be appropriate to place the Treatment Plan on either the northwestern portion of the
Whitney Barrel property or the Murphy Waste Oil property. It is more appropriate, practicable
and equitable that as the bulk of the groundwater contamination is present on these
properties, the Treatment Plant should be placed on one or both of these properties rather than
on the arena property, which is relatively clean.

EPA Response: EPA acknowledges the 280 Salem Street, LLC's comment and plans for
expanding the hockey arena to the north of the existing arena. EPA 's conceptual plan for the
selected groundwater remedy conceptually illustrated the location of the groundwater treatment
plant to the north of the existing hockey arena and described the location as "TO BE
DETERMINED. " The pre-design and design process will consider existing conditions on the
properties before a final decision is made regarding the location of the groundwater treatment
plant.

280 Salem Street, LLC Comment 7:

Finally, a dog daycare business has been in operation at the property for more than ten
years. The dog daycare facility is located inside the building as well as an extensive outside area
covered with artificial turf on which the dogs are exercised. The activities proposed at the
Aberjona property as well as the other Southwest Properties will significantly disrupt this
business' ability to operate during the proposed two year construction period. First, the work
will prevent the use of the site for the daycare business. Second, excavation activities will
damage the artificial turf. In all likelihood, the responsible parties will be required to replace the
expensive artificial turf in its entirety rather than patch it. Third, the construction activities will
be disruptive to property access and egress. Finally, the construction equipment noise will be
significantly disruptive to the animals.

EPA Response: See above response to 280 Salem Street, LLC Comment 3.

Comments received from Aberjona Study Coalition, Inc. (ASC) by letter dated 8/11/17

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ASC Comment 1:

After reviewing the RI, FS and [Proposed] Plan, we believe that overall the Plan is
implementable, and with the proposed institutional controls, will result in properties that
are safe for current and future uses of the properties.

EPA Response: EPA acknowledges the ASC's comment and agrees that the selected remedy is
implementable and will result in properties that are safe for current andfuture uses.

ASC Comment 2:

What level of disruption is anticipated for businesses operating at these properties?

Tenants may not be as well informed as owners of the properties. Measures should be taken to
accommodate such tenants during the cleanup. Tenants of these properties should be given as
much notice as possible regarding activities that could disrupt business operations, especially if
such activities will have a major impact on business operations.

EPA Response: The selected remedy, through the remedial design process, will include a
sequencing plan for implementing the remedy in a manner that minimizes disruptions to on-
going business operations, to the extent practical, including determining whether existing
business on the properties will need to be relocated.

ASC Comment 3:

While the institutional controls will remain in place [over the course of the estimated 20 years for
groundwater treatment], a review of potential vapor intrusion issues should be specifically
required as part of the Five Year Review to assess protectiveness of the [Proposed] Plan.

EPA Response: As specified in the selected remedy, "institutional controls require the
evaluation of the vapor intrusion pathway if a change in building usage of any of the existing
buildings is contemplated or as part of new building construction, including any
addition/alteration to existing buildings on any of the properties. Should someone wish to
demonstrate that there are no unacceptable risks from vapor intrusion and therefore mitigation
systems are not required, an evaluation of vapor intrusion risks (following EPA-approved
procedures and subject to EPA approval) may be performed prior to a change in building usage
or the building of structures above the VOC plume to demonstrate that vapor intrusion risks are
within or below EPA's target risk levels (risk range of 10~4 to 10~6 and/or a target organ HI of
1). " (ROD, Section L) The review of institutional controls including this vapor intrusion
pathway will be included as part of the Five Year Review process.

Record of Decision

Southwest Properties, Operable Unit 4 (OU4)

Wells G&H Superfund Site	September 2017

Woburn, Massachusetts	Page 132 of 137

-------
Record of Decision
Part 3: The Decision Summary

ASC Comment 4:

Given that institutional controls are a key part of the Plan, specific deed restrictions and
institutional controls should be detailed and the public should be informed of these controls
to ensure that public health will be protected.

EPA Response: As described in the selected remedy, "the details of the Institutional Controls
will be resolved during the pre-design and remedial design phase in coordination with the
parties performing the Remedial Action, impacted landowners, local officials, andMassDEP.
Institutional Controls may be implemented through measures that may include, but are not
limited to, a local Town ordinance, a Notice of Activity and Use Limitation (NAUL), or a Grant
of Environmental Restriction and Easement (GERE). " (ROD, Section L)

ASC Comment 5:

The Proposed Plan includes institutional controls on groundwater. The Massachusetts
Contingency Plan specifies that groundwater aquifers are state resources and that institutional
controls cannot be placed on groundwater unless the State designates these groundwater areas as
inappropriate for the uses that pose risk in the human health risk characterization.

EPA Response: The selected remedy requires institutional controls for contaminated
groundwater only until cleanup levels are achieved. The selected remedy in the Record of
Decision states that the institutional controls, "... prohibit future use of impacted groundwater
as a drinking water source until cleanup levels are achieved. " (ROD, Section L) EPA will
coordinate with MassDEP during the remedial design and remedial action, including with
respect to implementation of the institutional controls.

ASC Comment 6:

For non-carcinogens, why is an Hazard Index of 1 used to develop PRGs? Using a target
hazard index of 1 for all chemicals leaves open the possibility that the cumulative hazard index
across all chemicals could be greater than 1. It is true that not all chemicals affect the body in the
same way, but without consideration of target organs affected by each chemical, would it not be
possible for risks to exceed State and Superfund guidelines?

EPA Response: Residual risk for the soil and sediment PRGs has been calculated in Appendix
C-12 of the Feasibility Study (FS), Tables C12-2 (soil) and CI2-3 (sediment). The residual risk
calculations were not updated as part of the 2017 FS Report Addendum - Technical
Memorandum because the changes to the PRGs, as described in the FS Report Addendum -

Record of Decision

Southwest Properties, Operable Unit 4 (OU4)

Wells G&H Superfund Site	September 2017

Woburn, Massachusetts	Page 133 of 137

-------
Record of Decision

	Part 3: The Decision Summary	

Technical Memorandum either reduced the residual risk (i.e., the PRGs decreased or
contaminants of concern were removed) or the PRGs increased, but by a negligible amount. No
residual risk calculation is performed for groundwater PRGs because, before the remedy is
considered complete, a risk evaluation will be performed on the residual groundwater
contamination to determine whether the remedy is protective. After all groundwater cleanup
levels have been met as determined by EPA, EPA will perform a risk evaluation which considers
additive risk from remaining COCs considering all potential routes of exposure to document the
residual risk based on exposure to groundwater at the site. The protectiveness of the remedy will
also be periodically assessed as part of the Five-Year Review process.

ASC Comment 7:

Best management practices should be implemented to ensure trucks do not track soil and
sediments from the property onto nearby roads and properties, especially for vehicles
operating off of paved areas at the site.

EPA Response: During the remedial design and remedial action, appropriate Health & Safety
Plans shall be prepared and implemented for the selected remedy, including the establishment of
exclusion, decontamination, and safe zones. EPA agrees that during the remedial design and
remedial action best management practices shall be implemented, including cleaning truck tires
and securing truck loads before exiting the SWP to minimize dirt on public roads.

ASC Comment 8:

ASC would appreciate the opportunity to review and comment on the findings of the pre-
design investigations to refine the vertical and horizontal extent of wetland sediment and
soil exceeding cleanup levels, as well as any changes to the proposed plan that significantly
affect the areal extent of the work to be conducted in the wetlands.

EPA Response: In the selected remedy, 'EPA has determined that because significant levels of
contamination exist in wetlands within the SWP cleanup areas, there is no practicable
alternative to permanently removing the contaminants from these wetlands. " (ROD, Section M)
EPA will continue to coordinate with the ASC, recipient of a Technical Assistance Grant, and
provide ASC with opportunity to review and comment on the remedial designs which will include
the findings of the pre-design investigations.

ASC Comment 9:

It is not clear what long-term monitoring is proposed to evaluate the effectiveness of the
soil remedy. All aspects of the proposed long-term monitoring should be clearly detailed in the

Record of Decision

Southwest Properties, Operable Unit 4 (OU4)

Wells G&H Superfund Site	September 2017

Woburn, Massachusetts	Page 134 of 137

-------
Record of Decision
Part 3: The Decision Summary

remedial design, including what actions will be taken if monitoring reveals that remediation
goals are not being met.

EPA Response: The details of the long-term monitoring will be determined during the remedial
design process.

ASC Comment 10:

Strong effort should be made to minimize temporary impacts of construction on the
floodplain. In the long term, as long as there is no net loss of flood storage capacity (as
proposed), and efforts are taken to minimize temporary impacts, the proposed plan is acceptable.

EPA Response: Under the selected remedy, 'EPA has determined there is no practicable
alternative to occupancy and modification of the Aberjona River floodplain. EPA will avoid or
minimize potential harmful temporary and permanent impacts on floodplain resources within the
500-year floodplain, to the extent practical, within the cleanup areas including the Murphy
Wetland. In addition, the cleanup plan selected by EPA includes provisions for no net flood
storage loss (e.g., soil removed prior to cap installation so no net flood storage loss, sediments
removed and clean wetland soils backfilled to original grades, etc.). " (ROD, Section M)

ASC Comment 11:

Site-specific calculations of health risks based on recreational exposure to soil indicate that
risks will be within generally recognized guidelines at a cleanup level for PCBs at 5.3
mg/kg. As proposed in the Plan, institutional controls should be implemented for properties
containing PCBs in soil above a concentration of 1 mg/kg to ensure that no future residences are
constructed in areas containing residual levels of PCB contamination above 1 mg/kg.

EPA Response: EPA agrees with the comment. The selected remedy, in compliance with TSCA,
requires "[RJisks from unrestricted exposure to PCBs between 1 milligram/kilogram and 5.3
milligrams/kilogram for PCBs in contaminated soil will be addressed by Institutional Controls
that will prevent residential, school, and daycare development (throughout the SWP except
within the existing residential area within the Aberjona parcel and in the Murphy Wetland where
no residential exposure is anticipated). " (ROD, Section M)

Comments from Massachusetts Department of Environmental Protection received by letter
on 8/11/17

Record of Decision

Southwest Properties, Operable Unit 4 (OU4)

Wells G&H Superfund Site	September 2017

Woburn, Massachusetts	Page 135 of 137

-------
Record of Decision

Part 3: The Decision Summary

MassDEP Comment 1:

MassDEP agrees with EPA's selection of the preferred remedial alternatives for the Southwest
Properties. MassDEP agrees that the preferred alternatives will meet ARARs and are protective
of human health and the environment. The preferred alternatives also represent the best balance
among the EPA's balancing criteria including long-term and short-term protection; reduction of
mobility, toxicity and volume of contamination; implementability, and cost. The preferred
alternatives can also be completed in a reasonable amount of time, and allow for the greatest
reuse of these properties on this portion of the site. Further, MassDEP does not support any of
the other (non-preferred) alternatives for soil, groundwater, NAPL or wetland remediation for
the reasons provided in the Proposed Plan.

EPA Response: EPA acknowledges MassDEP's comment and agreement with the Agency's
selected remedy.

MassDEP Comment 2:

MassDEP understands that impermeable caps will not be required over NAPL
contaminated soils on the Murphy and Whitney properties or at the Northern Whitney
Soil Area because soils will likely be excavated to the water table, thereby preventing
further leaching from soils to groundwater. However, MassDEP recommends that
impervious caps be required over these areas, since 1) the water table could fluctuate in
depth over time, thereby exposing contaminated soils that were previously below the
water table, and 2) uncapped soils may give the impression that soils in the uncapped
areas have been fully remediated, even below the water table.

EPA Response: EPA's 2017 FS Report Addendum and the selected remedy includes
impermeable caps being extended over all soil remediation areas. This also covers significant
areas of the NAPL excavation area. However, capping is not an identified component of the
NAPL remedy since all NAPL-contaminated soil is to be removed, to the extent practicable

MassDEP Comment 3:

The de-watering of the excavation requires the treatment of the water extracted. It was

indicted that the water be treated on site or appropriately discharged to a POTW. If the
POTW is the MWRA system, it has been the MassDEP's understanding that the MWRA
does not take discharges from contaminated sites. It is suggested that EPA confirm if
the MWRA is willing to take dewatering discharge, if they are not, then eliminate this
from the ROD.

Record of Decision

Southwest Properties, Operable Unit 4 (OU4)

Wells G&H Superfund Site September 2017

Woburn, Massachusetts Page 136 of 137

-------
Record of Decision

	Part 3: The Decision Summary	

EPA Response: EPA has clarified in the Record of Decision that the de-watering of the
excavation and the options for water treatment includes as an option, if appropriate, approved
discharge to a POTW. A determination as to whether water generatedfrom the remedial action
may be discharged to a POTW will be made during remedial design, so it is premature to
exclude it as an option in the ROD.

Comments Received at the August 3, 2017 Public Hearing

Resident Comment:

Local resident stated, "they did some work down there at the cranberry bogs and I have to say
they did a nice job down there. How do you know when you're going to do the ground and going
to test it all, how do the common layperson like myself get updates of the testing after the job is
done? Like, I have no idea now how cranberry bogs are doing after all the work is done there. I
don't know where you get that information of, you know, six months I'm going to test it and see
how it is doing and stuff like that. I just don't know, you know — we agree and everything and all
of a sudden we just take your word that it's going to be all okay and stuff like that, and it's still
okay. I just don't know how that works."

EPA Response: The Commenter was addressing an area along the Aberjona River outside of
OU4 (addressed under the cleanup plan for Industri-plex OU2 remedy, that includes the
Aberjona River within the Wells G&H Site). Therefore, his comments are outside of the scope of
this OU4 Responsiveness Summary.

However, EPA provides the following general information regarding where the public may find
current information on the Wells G&H Superfund Site. The public can view current public
information for the site by navigating to the site's URL https://www.epa.gov/superfimd/wellsgh
using an internet connection. Site reports and Administrative Recordfiles are available using the
links in the "Site Reports and Documents " (green box) on the right side of the internet Site
Profile Page. Note that public internet access is available at the Woburn Public Library, 45
Pleasant St, Woburn, MA. Future Administrative Records files and other documents will be
automatically added to these collections. In addition, paper copies of documents can be
reviewed (please call to schedule) at the EPA New England Records Center, 5 Post Office Sq.,
First Floor, Boston, MA.

Record of Decision

Southwest Properties, Operable Unit 4 (OU4)

Wells G&H Superfund Site	September 2017

Woburn, Massachusetts	Page 137 of 137

-------
APPENDICES

Appendix A:
Appendix B:
Appendix C:
Appendix D:
Appendix E:
Appendix F:
Appendix G:

State DEP Letter of Concurrence

Tables

Figures

ARARs Tables

TSCA Determination

Acronyms and Abbreviations

Administrative Record Index and Guidance
Documents

-------
Appendix A: State DEP Letter of
Concurrence

-------


Commonwealth of Massachusetts

Executive Office of Energy & Environmental Affairs

Department of Environmental Protection

One Winter Street Boston, MA 02103 • 617-292-5500

Charles D Baker	Matthew A. Beaton

Governor	Secretary

K.nyn E Polito	Martin Suuberg

Lieutenant Governor	Commissioner

September 28, 2017

Mr. Bryan Olson, Director

Office of Site Remediation and Restoration
U.S. EPA Region I
Suite 100

5 Post Office Square
Boston, MA 02109

Subject: MassDEP Concurrence Letter

Record of Decision for Wells G&H Superfund Site
Operable Unit #4 - Southwest Properties

Dear Mr. Olson:

The Department of Environmental Protection (MassDEP) has reviewed the U.S.
Environmental Protection Agency's (EPA's) proposed Record of Decision (ROD) for the
Wells G&H Superfund site - Operable Unit #4 (OU4) (the Site). This letter provides
MassDEP's concurrence of the ROD, subject to some considerations discussed below.

Background: EPA has issued a ROD for the Southwest Properties (OU4) of the Wells
G&H site. This ROD was developed after many years of ongoing investigations and
evaluations. Most recent assessments have included the 2014 (final) Baseline Risk
Assessment, the November 2016 Remedial Investigation, the December 2016
Feasibility Study, the July 2017 Feasibility Report Addendum - Technical
Memorandum, and July 2017 Proposed Plan.

The Selected Remedy presented in the ROD will adequately protect human health and
the environment by eliminating, reducing, or controlling exposures to human and
environmental receptors through treatment, engineering controls and Institutional
Controls. The SWP will be cleaned up to support industrial/commercial/recreational
use. The main components of the Remedy include:

This Information is available In alternate format. Contact Michelle Waters-Ekanem, Director of Divsrsity/Civll Rights at 817-292-5751.

TTY# MassReiay Service 1-800-439-2370
MassDEP Website: www.mass.gov/dep

Printed on Recycled Paper

-------
Wells G&H 0U4 ROD MassDEP Concurrence Letter

September 28,2017

Page 2 of 3

1.	Excavation and off-site disposal of approximately 5,400 cubic yards of significantly
contaminated soil at the designated Northern Whitney Soil Area, and blending
remaining contaminated soil below the water table with an amendment prior to
backfilling to provide soil and localized groundwater treatment. In addition,
excavation and off-site disposal of approximately 12,400 cubic yards of soil to
facilitate capping and maintain flood storage, and construction of impermeable caps
over the remaining lower concentration soils that exceed cleanup levels to reduce
soil exposure risks and/or prevent contaminant movement to groundwater;

2.	Excavation and off-site disposal of NAPL, including approximately 6,000 cubic yards
of NAPL-contaminated soil and the blending any remaining NAPL-contaminated soil
below the water table with an amendment prior to backfilling to provide soil and
localized groundwater treatment;

3.	Containment and cleanup of groundwater contaminants by pumping and treating the

groundwater;

4.	Excavation and off-site disposal of approximately 7,000 cubic yards of wetland
sediment/soil exceeding cleanup levels and wetland restoration;

5.	Long-term monitoring;

6.	institutional Controls to maintain the integrity of the soil caps, to prevent
development of the properties for residential, school, and daycare use, to prohibit
use of contaminated groundwater until cleanup levels are met, and to require
evaluation of the vapor intrusion pathway if a change in usage of any of the existing
commercial buildings is contemplated, or as part of new building construction,
including any addition/alteration to existing buildings on any of the properties.

The proposed remedy is estimated to cost approximately $19.1 million and is expected

to take 1-2 years to construct. Groundwater is estimated to achieve cleanup standards

in 20 years.

MassDEP Concurrence,

MassDEP agrees with EPA's Selected Remedy for the Southwest Properties (OU4) of
the Wells G&H Superfund site. MassDEP agrees that the Selected Remedy would
meet ARARs and be protective of both human health and the environment. MassDEP
believes the Selected Remedy represents the best balance among the EPA's balancing
criteria including long-term and short-term protection; reduction of mobility, toxicity and
volume of contamination; implementability, and cost. The Selected Remedy can also
be completed in a reasonable amount of time, and allow for the greatest reuse of these
properties on this portion of the site. Therefore, for these reasons, MassDEP concurs
with the Selected Remedy as presented in ROD.

If you have any questions or comments on this letter, please contact, me or Paul Craffey at
(617) 292-5591.

-------
Weils G&H 0U4 ROD MassDEP Concurrence Letter
September 28,2017
Page 3 of 3

Very truly yours,

Paul W. Locke,
Assistant Commissioner

e-file: 20170928_WellsGHOU4_RODConcurrenceLtr.docx

-------
Appendix B: Tables

-------
ROD RISK WORKSHEET

Table G-1

Summary of Chemical of Concern and Medium-Specific Exposure Point Concentration

Scenario Timeframe: Future
Medium: Soil

Exposure Medium: Surface Soil

Exposure Point

Chemical of
Concern

Concentration Detected

Units

Frequency of
Detection

Exposure Point
Concentration

Exposure Point
Concentration
Units

Statistical
Measure

(1)

Minimum

Maximum

Whitney Property



















Vinyl Chloride

6.9E-03

3.1E+00

mg/kg

5/36

3.1E+00

mg/kg

Max





















Total PCBs

1.9E-02

4.3E+01

mg/kg

31/35

9.1E+00

mg/kg

95% UCL



PCBTEQ

8.8E-07

7.2E-04

mg/kg

24/24

1.6E-04

mg/kg

95% UCL





















Arsenic

2.3E+00

1.7E+01

mg/kg

37/37

8.4E+00

mg/kg

95% UCL



Chromium (VI)

4.8E-01

2.9E+01

mg/kg

29/37

8.7E+00

mg/kg

95% UCL



















Murphy Property



















Thallium

5.40E-02

1.00E+01

mg/kg

10/17

6.61 E+00

mg/kg

95% UCL



















Key

(1) Statistics: Maximum Detected Value (Max); 95% UCL (95% UCL); Arithmetic Mean (Mean)
PCB - Polychlorinated biphenyl.

TEQ - Toxicity equivalent.

The table represents the future chemicals of concern (COCs) and exposure point concentrations (EPCs) for each of the COCs detected in surface soil at the Whitney Property and Murphy Property (i.e., the
concentrations that will be used to estimate the exposure and risk for each COC in surface soil). The table includes the range of concentrations detected for each COC, as well as the frequency of detection (i.e., the
number of times the chemical was detected in the samples collected at the site), the EPC, and how the EPC was derived. This table indicates that: vinyl chloride, benzo(a)anthracene, benzo(b)fluoranthene,
benzo(a)pyrene, indeno(1,2,3-cd)pyrene, dibenz(a,h)anthracene, total PCBs, PCB TEQ, arsenic and hexavalent chromium are the only COCs in surface soil at the Whitney Property; and thallium is the only COC in
surface soil at the Murphy Property. The 95% UCL on the arithmetic mean was used as the EPC for all COCs except for vinyl chloride at the Whitney Property, for which maximum detected concentrations was used as
the EPC.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 1 of 17	draftRODSWPTablesG1-G13-HH-073117.xls

-------
ROD RISK WORKSHEET

Table G-2

Summary of Chemical of Concern and Medium-Specific Exposure Point Concentration

Scenario Timeframe: Future















Medium: Soil

















Exposure Medium: Subsurface Soil















Exposure Point

Chemical of Concern

Concentration Detected

Units

Frequency of
Detection

Exposure Point
Concentration

Exposure Point
Concentration
Units

Statistical
Measure





Minimum

Maximum









-------
ROD RISK WORKSHEET

Table G-3

Summary of Chemical of Concern and Medium-Specific Exposure Point Concentration

Scenario Timeframe: Future
Medium: Sediment
Exposure Medium: Sediment

Exposure Point

Chemical of
Concern

Concentration Detected

Minimum

Maximum

Units

Frequency of
Detection

Exposure Point
Concentration

Exposure Point
Concentration
Units

Statistical
Measure

(1)

Murphy Wetland

C11-C22 Aromatics

2.2E+01

9.7E+04

mg/kg

43/43

2.6E+04

mg/kg

95% UCL

Total PCBs

1.1E-01

4.5E+02

mg/kg

55/59

7.5E+01

mg/kg

95% UCL

Lead

3.0E+01

3.5E+04

mg/kg

62/62

2.4E+03

mg/kg

Mean

Key

(1) Statistics: Maximum Detected Value (Max); 95% UCL (95% UCL); Arithmetic Mean (Mean)
PCB - Polychlorinated biphenyl.

The table represents the future chemicals of concern (COCs) and exposure point concentrations (EPCs) for the COCs detected in sediment (i.e., the concentrations that will be used to estimate the exposure and risk for
each COC in sediment). The table includes the range of concentrations detected for each COC, as well as the frequency of detection (i.e., the number of times the chemical was detected in the samples collected at the
site), the EPC, and how the EPC was derived. This table indicates that Total PCBs, C11-C22 aromatics and lead are the only COCs in Murphy Wetland sediment. The 95% UCL on the arithmetic mean was used as
the EPC for Total PCBs and C11-C22 aromatics, while the mean concentration was used as the EPC for lead.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 3 of 17

draft ROD SWP Tables G1-G13 -HH-073117.xls

-------
ROD RISK WORKSHEET

Table G-4

Summary of Chemical of Concern and Medium-Specific Exposure Point Concentration

Scenario Timeframe: Future





















Medium: Groundwater





















Exposure Medium: Groundwater





















Exposure Point

Chemical of Concern

Concentration

Detected



Units

Frequency of
Detection

Exposure Point
Concentration

Exposure Point
Concentration
Units

Statistical
Measure







Minimum

Maximum











(1)

Groundwater



















Benzene

5 9E-03

5 5E+01

ng/L

37/56

5 5E+01



Max



Dichlorobenzene, 1,4-

8 1E-02

3 7E+01

ng/L

13/38

3 7E+01



Max



Dichloroethane, 1,1-

1 2E-01

1 2E+03

ng/L

24/38

1 2E+03



Max



Dichloroethane, 1,2-

6 0E-03

6 9E+00

ng/L

19/38

6 9E+00



Max



Dichloroethene. 1.1-(l)

6 7E-03

6 8E+01

ng/L

31/56

6 8E+01



Max



Dichloroethene, cis-1,2-

7 9E-03

3 5E+04

ng/L

46/56

3 5E+04



Max



Dichloroethene, trans-1,2-(l)

4 5E-03

1 9E+02

ng/L

37/56

1 9E+02



Max



Dioxane, 1,4-

2 2E-01

7 9E+01

ng/L

11/18

7 9E+01



Max



Ethylbenzene

5 9E-03

1 1E+02

ng/L

24/56

1 1E+02



Max



Methyl tert-Butyl Ether

1 1E-01

8 6E+01

ng/L

16/38

8 6E+01



Max



Methylene Chloride

1 5E+03

1 5E+03

ng/L

1/38

1 5E+03



Max



T etrachloroethyl ene

7 0E-03

2 0E+03

ng/L

47/56

2 0E+03



Max



Trichlorobenzene, 1,2,3-

1 5E-01

5 0E+01

ng/L

5/38

5 0E+01



Max



Trichlorobenzene, 1,2,4-

1 2E-01

1 7E+02

ng/L

8/38

1 7E+02



Max



Trichloroethane. 1.1.1-(l)

1 2E-01

3 3E+03

ng/L

20/56

3 3E+03



Max



Trichloroethane, 1,1,2-

72E-01

72E-01

ng/L

1/38

72E-01



Max



Trichloroethylene

4 1E-03

4 0E+03

ng/L

53/56

4 0E+03



Max



Vinyl Chloride

4 6E-03

2 6E+03

ng/L

36/56

2 6E+03



Max



Xylenes (total)

1 7E-02

5 1E+02

ng/L

27/56

5 1E+02



Max





















C5-C8 Aliphatics

3 9E+01

4 5E+03

ng/L

13/38

4 5E+03



Max



C9-C12 Aliphatics

5 3E+01

9 0E+01

ng/L

5/38

9 0E+01



Max



C9-C10 Aromatics

5 1E+01

1 0E+03

ng/L

10/38

1 0E+03



Max



C9-C18Aliphatics

1 4E+02

1 4E+02

ng/L

1/38

1 4E+02



Max



C11-C22 Aromatics

1 4E+02

5 9E+02

ng/L

9/38

5 9E+02



Max





















Benzo(a)pyrene

1 4E-02

8 8E-02

ng/L

6/38

8 8E-02



Max



Methylnaphthalene, 2-

3 5E-01

8 9E+01

ng/L

4/38

8 9E+01



Max



Naphthalene

1 2E-01

3 4E+02

ng/L

7/38

3 4E+02



Max





















PCB TEO

1 4E-08

1 1E-04

ng/L

38/38

1 1E-04



Max



Total PCBs

2 1E-06

2 5E+01

ng/L

38/38

2 5E+01



Max





















4,4'-DDD

1 0E-03

8 5E-01

ng/L

12/37

8 5E-01



Max



4.4'-DDE (2)

75E-04

8 3E-02

ng/L

10/38

8 3E-02



Max



4,4'-D DT

1 1E-03

3 4E-01

ng/L

12/37

3 4E-01



Max



Aldrin

6 7E-03

2 2E-01

ng/L

7/36

2 2E-01



Max



alpha-BHC

2 7E-03

3 1E+00

ng/L

5/36

3 1E+00



Max



alpha-Chlordane

1 0E-03

4 3E-01

ng/L

11/37

4 3E-01



Max



beta-BHC

1 3E-03

4 1E-01

ng/L

9/36

4 1E-01



Max



Dieldrin

1 3E-03

2 0E-02

ng/L

6/36

2 0E-02



Max



Lindane

9 7E-03

5 7E+00

ng/L

3/37

5 7E+00



Max



gamma-Chlordane

1 6E-03

3 4E-01

ng/L

14/38

3 4E-01



Max



Heptachlor

3 6E-02

6 0E-01

ng/L

2/33

6 0E-01



Max



Heptachlor Epoxide

3 3E-03

1 9E-01

ng/L

6/36

1 9E-01



Max





















Arsenic

4 4E-01

3 9E+02

ng/L

35/52

3 9E+02



Max



Cobalt

1 9E-01

1 6E+01

ng/L

39/52

1 6E+01



Max



Iron

6 7E+01

3 4E+04

ng/L

55/56

3 4E+04



Max



Lead

5 0E-02

1 3E+02

ng/L

41/52

1 3E+02



Max



Manganese

3 6E+00

4 9E+03

ng/L

56/56

4 9E+03



Max

Whitney Property
Shallow Groundwater



















Dichloroethene, cis-1,2-

3 3E-02

3 5E+04

ng/L

9/11

3 5E+04



Max



T etrachloroethyl ene

9 7E-03

2 0E+03

ng/L

7/11

2 0E+03



Max



Trichloroethylene

7 2E-02

4 0E+03

ng/L

11/11

4 0E+03



Max



















Murphy Property
Shallow Groundwater



















Dichloroethene, cis-1,2-

3 8E-01

2 4E+04

ng/L

9/10

2 40E+04

ng/L

Max



















Key























(1) Statistics Maximu

Detected Value (Max), 95

/» UCL (95

/o UCL), Ar



CM

ean (Mean)









Multiple results trom e

ch on-site monitoring well v

ere



as discret

sample











PCB - Polychlorinated biphenyl





















TEO - Toxicity equivalent





















MCL - Maximum conta

ninant level





















(1) Though not identit

das a risk contributor inth



seline

HHRA or n

longer k

entitled as a risk c



due to a toxicity value change, these c

ompounds are Includec

as COCs due to MCL exceedances

(2) Though not identit

das a COC in the baseline

HHRA.th

s chemical





v be identified as a

COC (s

eAttachment

of the 2017 FS Report Addendum)

The table represents the future chemicals ot conce

and the organic chemicals, benzene, cis-1,2-dichlo
and shallow groundwater The maximum detectec
groundwater

n (COCs;
ach COCi

SWP-wid
ans-1,2-di

e SWP),

oncentrations (EPCs) for each of the COCs detected in SWP-wide
ow groundwater) The table includes the range of concentrations
he EPC, and how the EPC was derived This table indicates that
ne, tetrachloroethylene, trichloroethylene, vinyl chloride, PCB TEO
ng multiple results from each monitoring well were treated as disc

groundwater and shall
detected for each COC
le inorganic chemicals
and total PCBs are the
ete samples, was usee

w groundwater (i e , the concentrations that
as well as the frequency of detection (i e , the
arsenic, cobalt, lead, iron, and manganese,
most frequently detected COCs in SWP-wide
as the EPC for each of the COCs detected in

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999}

Page 4 of 17

draff ROD SWP Tables G1 -G13 -HH-073117.xls

-------
ROD RISK WORKSHEET

Table G-5

Cancer Toxicity Data Summary

Pathway: Ingestion, Dermal

Chemical of
Concern

Oral Cancer
Slope Factor

Dermal Cancer
Slope Factor

Slope Factor
Units

Weight of
Evidence/Cancer
Guideline Description

Source

Date (1)
(MM/DD/YYYY)

Benzene

5.5E-02

5.5E-02

(mg/kg-day)"1

A

IRIS

02/01/17

Dichlorobenzene, 1,4-

5.4E-03

5.4E-03

(mg/kg-day)"'

N/A

CalEPA

02/01/17

Dichloroethane, 1,1-

5.7E-03

5.7E-03

(mg/kg-day)"'

C

CalEPA

02/01/17

Dichloroethane, 1,2-

9.1E-02

9.1E-02

(mg/kg-day)"'

B2

IRIS

02/01/17

Dichloroethene, 1,1-

N/A

N/A

(mg/kg-day)"'

Equivocal

IRIS

02/01/17

Dichloroethene, cis-1,2-

N/A

N/A

(mg/kg-day)"'

Inadequate

IRIS

02/01/17

Dichloroethene, trans-1,2-

N/A

N/A

(mg/kg-day)"'

Inadequate

IRIS

02/01/17

Dioxane, 1,4-

1.0E-01

1.0E-01

(mg/kg-day)"'

Likely

IRIS

02/01/17

Ethylbenzene

1.1E-02

1.1E-02

(mg/kg-day)"'

N/A

CalEPA

02/01/17

Methyl tert-Butyl Ether

1.8E-03

1.8E-03

(mg/kg-day)"'

N/A

CalEPA

02/01/17

Methylene Chloride

2.0E-03

2.0E-03

(mg/kg-day)"'

Likely

IRIS

02/01/17

Tetrachloroethylene

2.1E-03

2.1E-03

(mg/kg-day)"'

Likely

IRIS

02/01/17

Trichlorobenzene, 1,2,3-

N/A

N/A

(mg/kg-day)"'

Inadequate

PPRTV

02/01/17

Trichlorobenzene, 1,2,4-

2.9E-02

2.9E-02

(mg/kg-day)"'

Likely

PPRTV

02/01/17

Trichloroethane, 1,1,1-

N/A

N/A

(mg/kg-day)"'

Inadequate

IRIS

02/01/17

Trichloroethane, 1,1,2-

5.7E-02

5.7E-02

(mg/kg-day)"'

C

IRIS

02/01/17

Trichloroethylene

4.6E-02

4.6E-02

(mg/kg-day)"'

Carcinogenic to humans

IRIS

02/01/17

Vinyl Chloride

7.2E-01

7.2E-01

(mg/kg-day)"'

A

IRIS

02/01/17

Xylenes (total)

N/A

N/A

(mg/kg-day)"'

Inadequate

IRIS

02/01/17















C5-C8 Aliphatics

N/A

N/A

(mg/kg-day)"'

Suggestive

PPRTV

02/01/17

C9-C12 Aliphatics

N/A

N/A

(mg/kg-day)"'

Inadequate

PPRTV

02/01/17

C9-C10 Aromatics

N/A

N/A

(mg/kg-day)"'

Inadequate

PPRTV

02/01/17

C9-C18 Aliphatics

N/A

N/A

(mg/kg-day)"'

Inadequate

PPRTV

02/01/17

C11-C22 Aromatics

N/A

N/A

(mg/kg-day)"'

Inadequate

PPRTV

02/01/17















Benzo(a)pyrene

1.0E+00

1.0E+00

(mg/kg-day)"'

Carcinogenic to humans

IRIS

02/01/17

bis(2-Ethylhexyl)phthalate

1.4E-02

1.4E-02

(mg/kg-day)"'

B2

IRIS

02/01/17

Methylnaphthalene, 2-

N/A

N/A

(mg/kg-day)"'

Inadequate

IRIS

02/01/17

Naphthalene

N/A

N/A

(mg/kg-day)"'

C

IRIS

02/01/17















PCB TEQ

1.3E+05

1.3E+05

(mg/kg-day)"'

N/A

CalEPA

02/01/17

Total PCBs

2.0E+00

2.0E+00

(mg/kg-day)"'

B2

IRIS

02/01/17















4,4'-DDD

2.4E-01

2.4E-01

(mg/kg-day)"'

B2

IRIS

02/01/17

4,4'-DDE

3.4E-01

3.4E-01

(mg/kg-day)"'

B2

IRIS

02/01/17

4,4'-DDT

3.4E-01

3.4E-01

(mg/kg-day)"'

B2

IRIS

02/01/17

Aldrin

1.7E+01

1.7E+01

(mg/kg-day)"'

B2

IRIS

02/01/17

alpha-BHC

6.3E+00

6.3E+00

(mg/kg-day)"'

B2

IRIS

02/01/17

alpha-Chlordane

3.5E-01

3.5E-01

(mg/kg-day)"'

B2

IRIS

02/01/17

beta-BHC

1.8E+00

1.8E+00

(mg/kg-day)"'

C

IRIS

02/01/17

Dieldrin

1.6E+01

1.6E+01

(mg/kg-day)"'

B2

IRIS

02/01/17

Lindane

1.1E+00

1.1E+00

(mg/kg-day)"'

N/A

CalEPA

02/01/17

gamma-Chlordane

3.5E-01

3.5E-01

(mg/kg-day)"'

B2

IRIS

02/01/17

Heptachlor

4.5E+00

4.5E+00

(mg/kg-day)"'

B2

IRIS

02/01/17

Heptachlor Epoxide

9.1E+00

9.1E+00

(mg/kg-day)"'

B2

IRIS

02/01/17















Arsenic

1.5E+00

1.5E+00

(mg/kg-day)"'

A

IRIS

02/01/17

Chromium (VI)

5.0E-01

2.0E+01

(mg/kg-day)"'

NA

NJDEP

02/01/17

Cobalt

N/A

N/A

(mg/kg-day)"'

Likely

PPRTV

02/01/17

Iron

N/A

N/A

(mg/kg-day)"'

Inadequate

PPRTV

02/01/17

Lead

N/A

N/A

(mg/kg-day)"'

B2

IRIS

02/01/17

Manganese

N/A

N/A

(mg/kg-day)"'

D

IRIS

02/01/17

Page 5 of 17

draft ROD SWP Tables G1-G13 -HH-073117.xls

-------
ROD RISK WORKSHEET

Table G-5

Cancer Toxicity Data Summary

Thallium

N/A

N/A

(mg/kg-day)"

Inadequate

IRIS

02/01/17















Pathway: Inhalation

Chemical of
Concern

Unit Risk

Units

Inhalation
Cancer Slope
Factor

Units

Weight of
Evidence/Cancer
Guideline Description

Source

Date <1)
(MM/DD/YYYY)

Benzene

7.8E-06

(ug/m3)1

N/A

(mg/kg-day)"'

A

IRIS

02/01/17

Dichlorobenzene, 1,4-

1.1E-05

(ug/m3)1

N/A

(mg/kg-day)"'

N/A

CalEPA

02/01/17

Dichloroethane, 1,1-

1.6E-06

(ug/m3)1

N/A

(mg/kg-day)'

C

CalEPA

02/01/17

Dichloroethane, 1,2-

2.6E-05

(ug/m3)1

N/A

(mg/kg-day)'

B2

IRIS

02/01/17

Dichloroethene, 1,1-

N/A

(ug/m3)'

N/A

(mg/kg-day)'

Suggestive

IRIS

02/01/17

Dichloroethene, cis-1,2-

N/A

(ug/m3)'

N/A

(mg/kg-day)'

Inadequate

IRIS

02/01/17

Dichloroethene, trans-1,2-

N/A

(Mg/m3)"1

N/A

(mg/kg-day)'

Inadequate

IRIS

02/01/17

Dioxane, 1,4-

5.0E-06

(Mg/m3)"1

N/A

(mg/kg-day)'

Likely

IRIS

02/01/17

Ethylbenzene

2.5E-06

(Mg/m3)"1

N/A

(mg/kg-day)'

N/A

CalEPA

02/01/17

Methyl tert-Butyl Ether

2.6E-07

(Mg/m3)"1

N/A

(mg/kg-day)'

N/A

CalEPA

02/01/17

Methylene Chloride

1.0E-08

(ug/m3)'

N/A

(mg/kg-day)'

Likely

IRIS

02/01/17

Tetrachloroethylene

2.6E-07

(ug/m3)'

N/A

(mg/kg-day)'

Likely

IRIS

02/01/17

Trichlorobenzene, 1,2,3-

N/A

(ug/m3)'

N/A

(mg/kg-day)'

Inadequate

PPRTV

02/01/17

Trichlorobenzene, 1,2,4-

N/A

(ug/m3)'

N/A

(mg/kg-day)'

Likely

PPRTV

02/01/17

Trichloroethane, 1,1,1-

N/A

(ug/m3)'

N/A

(mg/kg-day)'

Inadequate

IRIS

02/01/17

Trichloroethane, 1,1,2-

1.6E-05

(ug/m3)'

N/A

(mg/kg-day)'

C

IRIS

02/01/17

Trichloroethylene

4.1E-06

(ug/m3)'

N/A

(mg/kg-day)'

Carcinogenic to humans

IRIS

02/01/17

Vinyl Chloride

4.4E-06

(ug/m3)"

N/A

(mg/kg-day)"

A

IRIS

02/01/17

Xylenes (total)

N/A

(ug/m3)1

N/A

(mg/kg-day)

Inadequate

IRIS

02/01/17

















C5-C8 Aliphatics

N/A

(ug/m3)-1

N/A

(mg/kg-day)

Suggestive

PPRTV

02/01/17

C9-C12 Aliphatics

N/A

(ug/m3)"

N/A

(mg/kg-day)"

Inadequate

PPRTV

02/01/17

C9-C10 Aromatics

N/A

(ug/m3)1

N/A

(mg/kg-day)

Inadequate

PPRTV

02/01/17

C9-C18 Aliphatics

N/A

(ug/m3)"

N/A

(mg/kg-day)"

Inadequate

PPRTV

02/01/17

C11-C22 Aromatics

N/A

(ug/m3)1

N/A

(mg/kg-day)"

Inadequate

PPRTV

02/01/17

















Benzo(a)pyrene

6.0E-04

(ug/m3)1

N/A

(mg/kg-day)"

Carcinogenic to humans

IRIS

02/01/17

bis(2-Ethylhexyl)phthalate

2.4E-06

(ug/m3)"

N/A

(mg/kg-day)"

B2

CalEPA

02/01/17

Methylnaphthalene, 2-

N/A

(ug/m3)1

N/A

(mg/kg-day)"

Inadequate

IRIS

02/01/17

Naphthalene

3.4E-05

(ug/m3)"

N/A

(mg/kg-day)"

C

CalEPA

02/01/17

















Page 6 of 17

draft ROD SWP Tables G1-G13 -HH-073117.xls

-------
ROD RISK WORKSHEET

Table G-5

Cancer Toxicity Data Summary

PCB TEQW

3.8E+01

(ug/rrTy

N/A

(mg/kg-day)"1

N/A

CalEPA

02/01/17

Total PCBs^

5.7E-04

(ug/m3)'

N/A

(mg/kg-day)"

B2

IRIS

02/01/17





(ug/rrTy

N/A

(mg/kg-day)"







4,4'-DDD

6.9E-05

(ug/m3)'

N/A

(mg/kg-day)"

B2

CalEPA

02/01/17

4,4'-DDE

9.7E-05

(ug/rrry

N/A

(mg/kg-day)"

B2

CalEPA

02/01/17

4,4'-DDT

9.7E-05

(ug/m3)'

N/A

(mg/kg-day)"

B2

IRIS

02/01/17

Aldrin

4.9E-03

(ug/rrT)

N/A

(mg/kg-day)

B2

IRIS

02/01/17

alpha-BHC

1.8E-03

(ug/m3)'

N/A

(mg/kg-day)"

B2

IRIS

02/01/17

alpha-Chlordarie

1.0E-04

(ug/rrTy

N/A

(mg/kg-day)"

B2

IRIS

02/01/17

beta-BHC

5.3E-04

(ug/m3)'

N/A

(mg/kg-day)"

C

IRIS

02/01/17

Dieldriri

4.6E-03

(ug/rrry

N/A

(mg/kg-day)"

B2

IRIS

02/01/17

Lindane

3.1E-04

(ug/m3)"'

N/A

(mg/kg-day)"

N/A

CalEPA

02/01/17

gamma-Chlordane

1.0E-04

(ug/rrTy

N/A

(mg/kg-day)"

B2

IRIS

02/01/17

Heptachlor[Z'

1.3E-03

(ug/m3)"'

N/A

(mg/kg-day)"

B2

IRIS

02/01/17

Heptachlor Epoxide

2.6E-03

(ug/rrry

N/A

(mg/kg-day)"

B2

IRIS

02/01/17

















Arsenic

4.3E-03

(ug/rrry

N/A

(mg/kg-day)"

A

IRIS

02/01/17

Chromium (VI)

8.4E-02

(ug/m3)"'

N/A

(mg/kg-day)"

A

IRIS

02/01/17

Cobalt

9.0E-03

(ug/m3)"

N/A

(mg/kg-day)"

Likely

PPRTV

02/01/17

Iron

N/A

(ug/m3)"'

N/A

(mg/kg-day)"

Inadequate

PPRTV

02/01/17

Lead

N/A

(ug/m3)"

N/A

(mg/kg-day)"

B2

IRIS

02/01/17

Manganese

N/A

(ug/m3)"'

N/A

(mg/kg-day)"

D

IRIS

02/01/17

Thallium

N/A

(ug/m3)"

N/A

(mg/kg-day)"

Inadequate

IRIS

02/01/17















Key







EPA Group







N/A: Not applicable







A - Human carcinogen





IRIS: Integrated Risk Information System, U.S. EPA





B1 - Probable human carcinogen - Indicates that limited human

data are available



PPRTV = Provisional Peer Reviewed Toxicity Value developed by STSC



B2 - Probable human carcinogen - indicates sufficient evidence

n animals and inadequate or no

NJDEP = New Jersey Department of Environmental Protection



evidence in humans





CalEPA = California Environmental Protection Agency, Office of Environmental



C - Possible human carcinogen





Health Hazard Assessment





D - Not classifiable as

a human carcinogen





PCB - Polychlorinated biphenyl.





E - Evidence of noncarcinogenicity





TEQ - Toxicity equivalent.















(1) Date indicates when source was last reviewed.













(2) Aldrin, chlordane, heptachlor, heptachlor epoxide, total PCBs and PCB TEQ were not classified as volatile at the time of the BHHRA, but have since been re-classified as volatile



(USEPA, 2015). The unit risk, if available, has been utilized during development of cleanup levels.









For PCBs, the RME slope factor presented represents the upper-bound slope factor for high risk and persistence situations.







The slope factor presented for trichloroethene is the adult-based value. For early-life exposures, tumor-specific slope factor values of 9.3E-03 (mg/kg-day)"1 for kidney tumors



and 3.7E-02 (mg/kg-day)"1

for combined liver tumors and non-Hodgkins lymphoma (NHL) are used in conjunction with age-dependent adjustment factors, as appropriate.



The unit risk presented for trichloroethene is the adult-based value. For early-life exposures, tumor-specific unit risk values of 1E-06 (ng/m3)"1 for kidney tumors





and 3.1 E-06 (ng/m3)"1 for combined liver tumors and non-Hodgkins lymphoma (NHL) are used in conjunction with age-dependent adjustment factors, as appropriate.





Age-dependent adjustment factors are used in conjunction with toxicity values, as appropriate, for carcinogenic PAHs, hexavalent chromium, trichloroethene, and vinyl chloride.



The slope factor and unit risk for benzo(a)pyrene has been updated since the baseline HHRA. Results presented on Risk Summary tables use the current toxicity values and



exposure parameters from the baseline HHRA. Refer to Attachment 2 of the July 2017 FS Study Report Addendum for a discussion of the results based on updated toxicity values.



This table provides the carcinogenic risk information which is relevant to the contaminants of concern in soil, sediment, and groundwater. At this time, slope factors are not available for the dermal route of
exposure. Thus, the dermal slope factors used in this assessment have been extrapolated from oral values. An adjustment factor is sometimes applied, and is dependent upon how well the chemical is absorbed
via the oral route. Adjustments are particularly important for chemicals with less than 50% absorption via the ingestion route. However, adjustment is not necessary for the chemicals evaluated at this site, except
for hexavalent chromium which has an adjustment factor of 0.025. For the remaining chemicals, the same oral slope factors as presented above were used as the dermal carcinogenic slope factors for these
contaminants. Thirty-two of the COCs considered carcinogenic via the inhalation route were determined to be primary risk drivers for at least one exposure pathway evaluated at the site.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 7 of 17	draft ROD SWP Tables G1-G13-HH-073117.xls

-------
ROD RISK WORKSHEET

Table G-6

Non-Cancer Toxicity Data Summary

Pathway: Ingestion, Dermal

Chemical of Concern

Chronic/
Subchroni
c

Oral RfD Value

Oral RfD
Units

Dermal
RfD

Dermal RfD
Units

Primary Target Organ

Combined
Uncertainty
/ Modifying
Factors

Sources of RfD:
Target Organ

Dates of RfD:
Target Organ (1)
(MM/DD/YYYY)

Benzene

Chronic

4.0E-03

mg/kg-day

4.0E-03

mg/kg-day

Immune System

300

IRIS

02/01/17

Dichlorobenzene, 1,4-

Chronic

7.0E-02

mg/kg-day

7.0E-02

mg/kg-day

Liver

100

ATSDR

02/01/17

Dichloroethane, 1,1-

Chronic

2.0E-01

mg/kg-day

2.0E-01

mg/kg-day

Kidney

3000

PPRTV

02/01/17

Dichloroethane, 1,2-

Chronic

6.0E-03

mg/kg-day

6.0E-03

mg/kg-day

Kidney

10,000

PPRTV

02/01/17

Dichloroethene, 1,1-

Chronic

5.0E-02

mg/kg-day

5.0E-02

mg/kg-day

Liver

100

IRIS

02/01/17

Dichloroethene, cis-1,2-

Chronic

2.0E-03

mg/kg-day

2.0E-03

mg/kg-day

Kidney

3000

IRIS

02/01/17

Dichloroethene, cis-1,2-

Subchronic

2.0E-02

mg/kg-day

2.0E-02

mg/kg-day

Kidney

300

PPRTV

02/01/17

Dichloroethene, trans-1,2-

Chronic

2.0E-02

mg/kg-day

2.0E-02

mg/kg-day

Immune System

3000

IRIS

02/01/17

Dioxane, 1,4-

Chronic

3.0E-02

mg/kg-day

3.0E-02

mg/kg-day

Kidney/Liver

300

IRIS

02/01/17

Ethylbenzene

Chronic

1.0E-01

mg/kg-day

1.0E-01

mg/kg-day

Kidney/Liver

1000

IRIS

02/01/17

Methyl tert-Butyl Ether

Chronic

N/A

mg/kg-day

N/A

mg/kg-day

N/A

N/A

N/A

02/01/17

Methylene Chloride

Chronic

6.0E-03

mg/kg-day

6.0E-03

mg/kg-day

Liver

30

IRIS

02/01/17

Tetrachloroethylene

Chronic

6.0E-03

mg/kg-day

6.0E-03

mg/kg-day

Nervous System

1000

IRIS

02/01/17

Tetrachloroethylene

Subchronic

6.0E-03

mg/kg-day

6.0E-03

mg/kg-day

Nervous System

1000

IRIS

02/01/17

Trichlorobenzene, 1,2,3-

Chronic

8.0E-04

mg/kg-day

8.0E-04

mg/kg-day

Endocrine/Liver

10,000

PPRTV

02/01/17

Trichlorobenzene, 1,2,4-

Chronic

1.0E-02

mg/kg-day

1.0E-02

mg/kg-day

Endocrine

1000

IRIS

02/01/17

Trichloroethane, 1,1,1-

Chronic

2.0E+00

mg/kg-day

2.0E+00

mg/kg-day

Liver

1000

IRIS

02/01/17

Trichloroethane, 1,1,2-

Chronic

4.0E-03

mg/kg-day

4.0E-03

mg/kg-day

Liver

1000

IRIS

02/01/17

Trichloroethylene

Chronic

5.0E-04

mg/kg-day

5.0E-04

mg/kg-day

Cardiovascular/Development
al/lmmune System

10 to 1000

IRIS

02/01/17

Trichloroethylene

Subchronic

5.0E-04

mg/kg-day

5.0E-04

mg/kg-day

Cardiovascular/Development
al/lmmune System

10 to 1000

IRIS

02/01/17

Vinyl Chloride

Chronic

3.0E-03

mg/kg-day

3.0E-03

mg/kg-day

Liver

30

IRIS

02/01/17

Xylenes (total)

Chronic

2.0E-01

mg/kg-day

2.0E-01

mg/kg-day

Nervous System

1000

IRIS

02/01/17





















C5-C8 Aliphatics (used in HHRA)

Chronic

6.0E-02

mg/kg-day

6.0E-02

mg/kg-day

Nervous System

N/A

HEAST

1997

C5-C8 Aliphatics(4'

Chronic

3.0E-01

mg/kg-day

3.0E-01

mg/kg-day

Nervous System

3,000

PPRTV

02/01/17

C9-C12 Aliphatics

Chronic

1.0E-02

mg/kg-day

1.0E-02

mg/kg-day

Blood/Kidney/Liver

10,000

PPRTV

02/01/17

C9-C10 Aromaticsl"'

Chronic

3.0E-02

mg/kg-day

3.0E-02

mg/kg-day

Blood

3000

PPRTV

02/01/17

C9-C18 Aliphatics

Chronic

1.0E-02

mg/kg-day

1.0E-02

mg/kg-day

Blood/Kidney/Liver

10,000

PPRTV

02/01/17

C11-C22 Aromatics

Chronic

3.0E-02

mg/kg-day

3.0E-02

mg/kg-day

Blood

3000

PPRTV

02/01/17





















Benzo(a)pyrene

Chronic

3.0E-04

mg/kg-day

3.0E-04

mg/kg-day

Developmental

3000

IRIS

02/01/17

bis(2-Ethylhexyl)ph thalate

Chronic

2.0E-02

mg/kg-day

2.0E-02

mg/kg-day

Liver

1000

IRIS

02/01/17

Methylnaphthalene, 2-

Chronic

4.0E-03

mg/kg-day

4.0E-03

mg/kg-day

Respiratory

1000

IRIS

02/01/17

Naphthalene

Chronic

2.0E-02

mg/kg-day

2.0E-02

mg/kg-day

Blood

3000

IRIS

02/01/17





















PCBTEQ

Chronic

7.0E-10

mg/kg-day

7.0E-10

mg/kg-day

Developmental/Reproductive

30

IRIS

02/01/17

PCBTEQ

Subchronic

7.0E-10

mg/kg-day

7.0E-10

mg/kg-day

Developmental/Reproductive

30

IRIS

02/01/17

Total PCBs

Chronic

2.0E-05

mg/kg-day

2.0E-05

mg/kg-day

Immune System/Skin

300

IRIS

02/01/17

Total PCBs

Subchronic

6.0E-05

mg/kg-day

6.0E-05

mg/kg-day

Immune System/Skin

100

IRIS

02/01/17





















4,4'-DDD

Chronic

N/A

mg/kg-day

N/A

mg/kg-day

N/A

N/A

N/A

02/01/17

4,4'-DDE

Chronic

N/A

mg/kg-day

N/A

mg/kg-day

N/A

N/A

N/A

02/01/17

4,4'-DDT

Chronic

5.0E-04

mg/kg-day

5.0E-04

mg/kg-day

Liver

100

IRIS

02/01/17

Aldrin

Chronic

3.0E-05

mg/kg-day

3.0E-05

mg/kg-day

Liver

1000

IRIS

02/01/17

alpha-BHC

Chronic

8.0E-03

mg/kg-day

8.0E-03

mg/kg-day

Liver

100

ATSDR

02/01/17

alpha-Chlordane

Chronic

5.0E-04

mg/kg-day

5.0E-04

mg/kg-day

Liver

300

IRIS

02/01/17

beta-BHC

Chronic

N/A

mg/kg-day

N/A

mg/kg-day

N/A

N/A

N/A

02/01/17

Dieldrin

Chronic

5.0E-05

mg/kg-day

5.0E-05

mg/kg-day

Liver

100

IRIS

02/01/17

Lindane

Chronic

3.0E-04

mg/kg-day

3.0E-04

mg/kg-day

Kidney/Liver

1000

IRIS

02/01/17

gamma-Chlordane

Chronic

5.0E-04

mg/kg-day

5.0E-04

mg/kg-day

Liver

300

IRIS

02/01/17

Heptachlor

Chronic

5.0E-04

mg/kg-day

5.0E-04

mg/kg-day

Liver

300

IRIS

02/01/17

Heptachlor Epoxide

Chronic

1.3E-05

mg/kg-day

1.3E-05

mg/kg-day

Liver

1000

IRIS

02/01/17





















Arsenic

Chronic

3.0E-04

mg/kg-day

3.0E-04

mg/kg-day

Skin

3

IRIS

02/01/17

Chromium (VI)

Chronic

3.0E-03

mg/kg-day

7.5E-05

mg/kg-day

Gl System

900

IRIS

02/01/17

Cobalt

Chronic

3.0E-04

mg/kg-day

3.0E-04

mg/kg-day

Endocrine

3000

PPRTV

02/01/17

Iron

Chronic

7.0E-01

mg/kg-day

7.0E-01

mg/kg-day

Gl System

2

PPRTV

02/01/17

Lead

Chronic

N/A

mg/kg-day

N/A

mg/kg-day

Nervous System

N/A

N/A

02/01/17

Manganese

Chronic

2.4E-02

mg/kg-day

9.6E-04

mg/kg-day

Nervous System

3

IRIS

02/01/17

Thallium

Chronic

1.0E-05

mg/kg-day

1.0E-05

mg/kg-day

Skin

3000

PPRTV

02/01/17





















Page 8 of 17

draft ROD SWP Tables G1-G13-HH-073117.xls

-------
ROD RISK WORKSHEET

Table G-6

Non-Cancer Toxicity Data Summary

Pathway: Inhalation

Chemical of Concern

Chronic/
Subchroni
c

Inhalation RfC

Inhalation
RfC Units

Inhalation
RfD

Inhalation RfD
Units

Primary Target Organ

Combined
Uncertainty
/ Modifying
Factors

Sources of RfC:
RfD: Target
Organ

Dates
(MM/DD/YYYY)

Benzene

Chronic

3.0E-02

mg/m3

N/A

N/A

Immune System

300

IRIS

02/01/17

Dichlorobenzene, 1,4-

Chronic

8.0E-01

mg/m3

N/A

N/A

Liver

100

IRIS

02/01/17

Dichloroethane, 1,1-

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Dichloroethane, 1,2-

Chronic

7.0E-03

mg/m3

N/A

N/A

Nervous System

3000

PPRTV

02/01/17

Dichloroethene, 1,1-

Chronic

2.0E-01

mg/m3

N/A

N/A

Liver

30

IRIS

02/01/17

Dichloroethene, cis-1,2-

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Dichloroethene, cis-1,2-

Subchronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Dichloroethene, trans-1,2-(3)

Chronic

6.0E-02

mg/m3

N/A

N/A

Respiratory/Liver

3000

PPRTV

03/01/14

Dioxane, 1,4-

Chronic

3.0E-02

mg/m3

N/A

N/A

Respiratory

1000

IRIS

02/01/17

Ethylbenzene

Chronic

1.0E+00

mg/m3

N/A

N/A

Developmental

300

IRIS

02/01/17

Methyl tert-Butyl Ether

Chronic

3.0E+00

mg/m3

N/A

N/A

Liver/Kidney

100

IRIS

02/01/17

Methylene Chloride

Chronic

6.0E-01

mg/m3

N/A

N/A

Liver

30

IRIS

02/01/17

Tetrachloroethylene

Chronic

4.0E-02

mg/m3

N/A

N/A

Nervous System

1000

IRIS

02/01/17

Tetrachloroethylene

Subchronic

4.0E-02

mg/m3

N/A

N/A

Nervous System

1000

IRIS

02/01/17

Trichlorobenzene, 1,2,3-

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Trichlorobenzene, 1,2,4-

Chronic

2.0E-03

mg/m3

N/A

N/A

Liver

3000

PPRTV

02/01/17

Trichloroethane, 1,1,1-

Chronic

5.0E+00

mg/m3

N/A

N/A

Liver

100

IRIS

02/01/17

Trichloroethane, 1,1,2-

Chronic

2.0E-04

mg/m3

N/A

N/A

Respiratory

3000

PPRTV

02/01/17

Trichloroethylene

Chronic

2.0E-03

mg/m3

N/A

N/A

Cardiovascular/Endocrine

10 to 1000

IRIS

02/01/17

Trichloroethylene

Subchronic

2.0E-03

mg/m3

N/A

N/A

Cardiovascular/Endocrine

10 to 1000

IRIS

02/01/17

Vinyl Chloride

Chronic

1.0E-01

mg/m3

N/A

N/A

Liver

30

IRIS

02/01/17

Xylenes (total)

Chronic

1.0E-01

mg/m3

N/A

N/A

Nervous System

300

IRIS

02/01/17





















C5-C8 Aliphatics

Chronic

6.0E-01

mg/m3

N/A

N/A

Respiratory

30

PPRTV

02/01/17

C9-C12 Aliphatics

Chronic

1.0E-01

mg/m3

N/A

N/A

Respiratory

100

PPRTV

02/01/17

C9-C10 Aromatics'51

Chronic

1.0E-01

mg/m3

N/A

N/A

Kidney

1000

PPRTV

02/01/17

C9-C18 Aliphatics

Chronic

1.0E-01

mg/m3

N/A

N/A

Respiratory

100

PPRTV

02/01/17

C11-C22|s|

Chronic

1.0E-01

mg/m3

N/A

N/A

Kidney

1000

PPRTV

02/01/17





















Benzo(a)pyrene

Chronic

2.0E-06

mg/m3

N/A

N/A

Developmental

3000

IRIS

02/01/17

bis(2-Ethylhexyl)ph thalate

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Methylnaphthalene, 2-(2)

Chronic

3.0E-03

mg/m3

N/A

N/A

Respiratory

3000

IRIS

02/01/17

Naphthalene

Chronic

3.0E-03

mg/m3

N/A

N/A

Respiratory

3000

IRIS

02/01/17





















PCB TEQ |!|

Chronic

4.0E-08

mg/m3

N/A

N/A

Immune System/Skin

100

CalEPA

02/01/17

PCB TEQ |!|

Subchronic

4.0E-08

mg/m3

N/A

N/A

Immune System/Skin

100

CalEPA

02/01/17

Total PCBs 161

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Total PCBs 161

Subchronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17





















4,4'-DDD

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

4,4'-DDE

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

4,4'-DDT

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Aldrin |!|

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

alpha-BHC

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

alpha-Chlordane(6)

Chronic

7.0E-04

mg/m3

N/A

N/A

Liver

1000

IRIS

02/01/17

beta-BHC

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Dieldrin

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Lindane

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

gamma-Chlordane (6)

Chronic

7.0E-04

mg/m3

N/A

N/A

Liver

1000

IRIS

02/01/17

Heptachlor(6)

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Heptachlor Epoxide(6)

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17





















Arsenic

Chronic

1.5E-05

mg/m3

N/A

N/A

Developmental

30

CalEPA

02/01/17

Chromium (VI)

Chronic

1.0E-04

mg/m3

N/A

N/A

Respiratory

300

IRIS

02/01/17

Cobalt

Chronic

6.0E-06

mg/m3

N/A

N/A

Respiratory

300

PPRTV

02/01/17

Iron

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Lead

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17

Manganese

Chronic

5.0E-05

mg/m3

N/A

N/A

Nervous System

1000

IRIS

02/01/17

Thallium

Chronic

N/A

mg/m3

N/A

N/A

N/A

N/A

N/A

02/01/17





















Key

N/A - No information available

Page 9 of 17

draft ROD SWP Tables G1-G13-HH-073117.xls

-------
ROD RISK WORKSHEET

Table G-6

Non-Cancer Toxicity Data Summary

IRIS: Integrated Risk Information System, U.S. EPA

PPRTV = Provisional Peer Reviewed Toxicity Value developed by STSC

HEAST = Health Effects Assessment Summary Tables

CalEPA = California Environmental Protection Agency, Office of Environmental Health Hazard Assessment
ATSDR = Agency for Toxic Substances and Disease Registry
PCB - Polychlorinated biphenyl.

TEQ - Toxicity equivalent.

(1)	Date indicates when source was last reviewed.

(2)	The RfC for naphthalene was used as a surrogate for 2-methylnaphthalene in the BHHRA, but has not been utilized for development of cleanup levels.

(3)	The RfC for trans-1,2-dichloroethene has been withdrawn from the PPRTV database.

(4)	The HEAST chronic RfD for n-hexane was used for the C5-C8 aliphatic fraction in the baseline HHRA, but has been withdrawn. The PPRTV subchronic RfD for n-hexane has been utilized as the chronic RfD
for the development of cleanup levels for the C5-C8 aliphatic fraction.

(5)	The RfD/RfC for C9-C10 aromatics and C11-C22 aromatics (high flash aromatic naphtha) from the PPRTV database was used for the BHHRA and cleanup level development. This approach is consistent with that recommended
in instances where target compounds (naphthalene, 2-methylnaphthalene, trimethylbenzenes) have been characterized separately.

(6)	Aldrin, chlordane, 4,4'-DDE, heptachlor, heptachlor epoxide, total PCBs and PCB TEQ were not classified as volatile at the time of the BHHRA, but have since been re-classified as volatile (USEPA, 2015).

The RfC, if available, has been utilized during development of cleanup levels.

The RfD for Aroclor 1254 was used as a surrogate for Aroclor 1260 (High risk and persistence; upper-bound slope factor).

The RfD and/or RfC for benzo(a)pyrene, 2-methylnaphthalene, trans-1,2-dichloroethene, and C5-C8 aliphatics have been updated since the baseline HHRA. Results presented on Risk Summary tables use the current toxicity values
and exposure parameters from the baseline HHRA. Refer to Attachment 2 of the July 2017 FS Study Report Addendum for a discussion of the results based on updated toxicity values.

This table provides non-carcinogenic risk information which is relevant to the contaminants of concern in soil, sediment, and groundwater. Forty-four of the COCs have oral toxicity data (or surrogate toxicity data) indicating their
potential for adverse non-carcinogenic health effects in humans. Chronic toxicity data available for the forty-three COCs for oral exposures have been used to develop chronic oral reference doses (RfDs), provided in this table. The
available chronic toxicity data indicate that benzene, trichloroethene, trans-1,2-dichloroethene and PCBs affect the immune system, 1,4-dichlorobenzene, 1,1 -dichloroethene, 1,4-dioxane, ethylbenzene, methylene chloride, 1,2,3-
trichlorobenzene, 1,1,1-trichloroethene, 1,1,2-trichloroethane, vinyl chloride, C9-C12 aliphatics, C9-C18 aliphatics, bis(2-ethylhexyl)phthalate, 4,4'-DDT, aldrin, alpha-BHC, chlordane, dieldrin, lindane, heptachlor, and heptachlor
epoxide affect the liver, 1,1-dichloroethane, 1,2-dichloroethane, cis-1,2-dichloroethene, 1,4-dioxane, ethylbenzene, C9-C12 aliphatics, C9-C18 aliphatics, and lindane affect the kidney, tetrachloroethene, xylene, C5-C8 aliphatics and
manganese affect the central nervous system, trichloroethene, benzo(a)pyrene and PCB TEQ are developmental toxicants, hexavalent chromium and iron affect the gastrointestinal system, C9-C12 aliphatics, C9-C10 aromatics, C9-
C18 aliphatics, C11-C22 aromatics and naphthalene the blood, and 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene, and cobalt affect the endocrine system, trichloroethylene affects the cardiovascular system, PCB TEQ affects the
reproductive system, and C9-C10 aromatics, C11-C22 aromatics, and 2 methylnaphthalene affects the respiratory system, and total PCBs, arsenic and thallium affect the skin. Dermal RfDs are not available for any of the COCs. As
was the case for the carcinogenic data, dermal RfDs can be extrapolated from oral RfDs by applying an adjustment factor as appropriate. Oral RfDs were adjusted for COCs with less than 50% absorption via the ingestion route
(hexavalent chromium and manganese) to derive dermal RfDs for these COCs. Inhalation reference concentrations (RfCs) are available for thirty-one COCs evaluated for the inhalation pathway.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 10 of 17

draft ROD SWP Tables G1-G13-HH-073117.xls

-------
ROD RISK WORKSHEET

Table G-7

Risk Characterization Summary - Carcinogens

Scenario Timeframe: Future
Receptor Population: Recreational User
Receptor Age: Young Child/Adult

Medium

Exposure
Medium

Exposure Point

Chemical of
Concern

Carcinogenic Risk

Ingestion

Inhalation

Dermal

External
(Radiation)

Produce
Ingestion

Exposure
Routes Total

Subsurface Soil

Whitney Property

Vinyl Chloride
Trichloroethylene

bis(2-Ethylhexyl)phthalate

alpha-Chlordane

gamma-Chlordane

alpha-BHC

Heptachlor

Heptachlor Epoxide

Dieldrin

4,4'-DDD

4,4'-DDT

Total PCBs
PCBTEQ

Arsenic
Chromium (VI)

7E-06
4E-06

2E-05
3E-05
2E-05
2E-04
3E-06
2E-05
1E-06
2E-06

3E-04
3E-04

2E-05
4E-06

3E-06
3E-06
7E-06
5E-05
8E-07
6E-06
4E-07
2E-07

1E-04
3E-05

2E-06
N/A

7E-06
4E-06

2E-05
3E-05
3E-05
2E-04
3E-06
2E-05
2E-06
3E-06

4E-04
3E-04

2E-05
4E-06

Subsurface Soil Risk Total =

Key

N/A - Toxicity criteria are not available to quantitatively address this route of exposure.
-- Route of exposure is not applicable to this medium.

PCB - Polychlorinated biphenyl.

TEQ - Toxicity equivalent.

This table provides risk estimates for the significant routes of exposure for future young child and adult recreational user exposed to subsurface soil at the Whitney Property. These risk estimates are based on a reasonable maximum exposure
and were developed by taking into account various conservative assumptions about exposure to subsurface soil by a young child and adult recreational user, as well as the toxicity of the COCs (vinyl chloride, trichloroethylene, bis(2-
ethylhexyl)phthalate, total PCBs, PCB TEQ, chlordane, alpha-BHC, heptachlor, heptachlor epoxide, dieldrin, 4,4'-DDD, 4,4'-DDT, arsenic, and hexavalent chromium). The total risk from exposure to soil for a future recreational user is estimated
to be 1 x 10~3 (Whitney Property subsurface soil). The COCs contributing most to this risk level are heptachlor, total PCBs, and PCB TEQ. This risk level indicates that if no clean-up action is taken, a young child and adult recreational user
would have an increased probability of 3 in 1,000 (Whitney Property subsurface soil) of developing cancer as a result of site-related exposure to the COCs in soil. Results presented use current toxicity values along with site-specific exposure
parameters from the baseline HHRA.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 11 of 17

draft ROD SWP Tables G1-G13 -HH-073117.xls

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ROD RISK WORKSHEET

Table G-8

Risk Characterization Summary - Non-Carcinogens

Scenario Timeframe: Future















Receptor Population: Recreational User













Receptor Age: Young Child/Adult















Medium

Exposure
Medium

Exposure Point

Chemical of
Concern

Primary Target Organ

Non-Carcinogenic Hazard Quotient











Ingestion

Inhalation

Dermal

Exposure
Routes Total

Soil

Surface Soil

Whitney Property



















Total PCBs

Immune System/Skin

1E+00



5E-01

2E+00

Surface Soil Hazard Index Total =

2E+00

Immune System Hazard Index =

2E+00

Soil

Subsurface Soil

Whitney Property



















Total PCBs

Immune System/Skin

6E+01



2E+01

8E+01







PCBTEQ

Developmental/Reproductive

3E+01



2E+00

3E+01

Subsurface Soil Hazard Index Total =

1E+02

Developmental Hazard Index =

3E+01

Reproductive Hazard Index =

3E+01

Skin Hazard Index =

8E+01

Immune System Hazard Index =

8E+01

Soil

Surface Soil

Murphy Property



















Thallium

Skin

2E+00



N/A

2E+00

Surface Soil Hazard Index Total =

2E+00

Skin Hazard Index =

2E+00

Soil

Subsurface Soil

Murphy Property



















Thallium

Skin

2E+00



N/A

2E+00

Subsurface Soil Hazard Index Total =

2E+00

Skin Hazard Index =

2E+00

Key

















N/A - Toxicity criteria are not available to quantitatively address this route of exposure.











-- Route of exposure is not applicable to this medium.













PCB - Polychlorinated biphenyl.















TEQ - Toxicity equivalent.















This table provides hazard quotients (HQs) for each route of exposure and the hazard index (sum of the hazard quotients) for all routes of exposure for future young child and adult recreational user exposed to surface and
subsurface soil at the following Areas of Interest: Whitney Property and Murphy Property. The Risk Assessment Guidance for Superfund (RAGS) states that, generally, a hazard index (HI) of greater than 1 indicates the
potential for adverse noncancer effects. The estimated target organ His between 2 and 80 indicate that the potential for adverse effects could occur from exposure to contaminated soil containing total PCBs, PCB TEQ and
thallium. Results presented use current toxicity values along with site-specific exposure parameters from the baseline HHRA.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 12 of 17	draft ROD SWP Tables G1 -G13 -HH-073117.xls

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ROD RISK WORKSHEET

Table G-9

Risk Characterization Summary - Non-Carcinogens

Scenario Timeframe: Future















Receptor Population: Construction Worker













Receptor Age: Adult















Medium

Exposure
Medium

Exposure Point

Chemical of
Concern

Primary Target Organ

Non-Carcinogenic Hazard Quotient











Ingestion

Inhalation

Dermal

Exposure
Routes Total

Soil

Subsurface Soil

Whitney Property

Total PCBs
PCBTEQ

Immune System/Skin
Developmental/Reproductive

1E+01
2E+01

4E-06

5E+00
1E+00

2E+01
2E+01

Subsurface Soil Hazard Index Total =

3E+01

Developmental Hazard Index =

2E+01

Reproductive Hazard Index =

2E+01

Skin Hazard Index =

2E+01

Immune System Hazard Index =

2E+01

Groundwater

Shallow Groundwater

Whitney Property

Dichloroethene, cis-1,2-

Tetrachloroethylene

Trichloroethylene

Kidney
Nervous System
Cardiovascular/Developmental/
Immune System

4E-01
8E-02

2E+00



3E+00
2E+00

1E+01

3.1E+00
1.7E+00

1.5E+01

Shallow Groundwater Hazard Index Total =

2E+01

Kidney Hazard Index =

3E+00

Nervous System Hazard Index =

2E+00

Cardiovascular System Hazard Index =

2E+01

Developmental Hazard Index =

2E+01

Immune System Hazard Index =

2E+01

Groundwater

Shallow Groundwater

Murphy Property

Dichloroethene, cis-1,2-

Kidney

3E-01



2E+00

2E+00

Shallow Groundwater Hazard Index Total =

2E+00

Kidney Hazard Index =

2E+00

Key

















N/A - Toxicity criteria are not available to quantitatively address this route of exposure.











-- Route of exposure is not applicable to this medium.













PCB - Polychlorinated biphenyl.















TEQ - Toxicity equivalent.















This table provides hazard quotients (HQs) for each route of exposure and the hazard index (sum of the hazard quotients) for all routes of exposure for a future adult construction worker exposed to subsurface soil and shallow
groundwater at the Whitney Property and shallow groundwater at the Murphy Property. The Risk Assessment Guidance for Superfund (RAGS) states that, generally, a hazard index (HI) of greater than 1 indicates the potential
for adverse noncancer effects. The estimated target organ His between 2 and 20 indicate that the potential for adverse effects could occur from exposure to contaminated soil containing total PCBs and PCB TEQ, and
contaminated shallow groundwater containing cis-1,2-dichloroethene, tetrachloroethylene, and trichloroethylene. Results presented use current toxicity values along with site-specific exposure parameters from the baseline
HHRA.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 13 of 17

draft ROD SWP Tables G1 -G13 -HH-073117.xls

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ROD RISK WORKSHEET

Table G-10

Risk Characterization Summary - Non-Carcinogens

Scenario Timeframe: Future
Receptor Population: Trespasser
Receptor Age: Older Child/Adolescent

Medium

Exposure
Medium

Exposure Point

Chemical of
Concern

Primary Target Organ

Non-Carcinogenic Hazard Quotient

Ingestion

Inhalation

Dermal

Exposure
Routes Total

Sediment

Sediment

Murphy Wetland

Total PCBs

Immune System/Skin

5E-01

1E+00

2E+00

Sediment Hazard Index Total:

2E+00

Skin Hazard Index =

2E+00

Immune System Hazard Index =

2E+00

Key

N/A - Toxicity criteria are not available to quantitatively address this route of exposure.
-- Route of exposure is not applicable to this medium.

PCB - Polychlorinated biphenyl.

This table provides hazard quotients (HQs) for each route of exposure and the hazard index (sum of the hazard quotients) for all routes of exposure for a future older child/adolescent trespasser exposed to sediment at the
Murphy Wetland. The Risk Assessment Guidance for Superfund (RAGS) states that, generally, a hazard index (HI) of greater than 1 indicates the potential for adverse noncancer effects. The estimated target organ HI of 2
indicates that the potential for adverse effects could occur from exposure to contaminated sediment containing total PCBs. Results presented use current toxicity values along with site-specific exposure parameters from the
baseline HHRA.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 14 of 17	draft ROD SWP Tables G1-G13 -HH-073117.xls

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ROD RISK WORKSHEET

Table G-11

Risk Characterization Summary - Non-Carcinogens

Scenario Timeframe: Future
Receptor Population: Recreational User
Receptor Age: Young Child/Adult

Medium

Exposure
Medium

Exposure Point

Chemical of
Concern

Primary Target Organ

Non-Carcinogenic Hazard Quotient

Ingestion

Inhalation

Dermal

Exposure
Routes Total

Sediment

Sediment

Murphy Wetland

Total PCBs
C11-C22 Aromatics

Immune System/Skin
Blood

5E+00
1E+00

4E+00
7E-01

1E+01
2E+00

Sediment Soil Hazard Index Total:

1E+01

Skin Hazard Index =

1E+01

Blood Hazard Index =

2E+00

Immune System Hazard Index =

1E+01

Key

N/A - Toxicity criteria are not available to quantitatively address this route of exposure.
-- Route of exposure is not applicable to this medium.

PCB - Polychlorinated biphenyl.

This table provides hazard quotients (HQs) for each route of exposure and the hazard index (sum of the hazard quotients) for all routes of exposure for a future young child/adult recreational user exposed to sediment at the
Murphy Wetland. The Risk Assessment Guidance for Superfund (RAGS) states that, generally, a hazard index (HI) of greater than 1 indicates the potential for adverse noncancer effects. The estimated target organ His
between 2 and 10 indicate that the potential for adverse effects could occur from exposure to contaminated sediment containing total PCBs and C11-C22 aromatics. Results presented use current toxicity values along with
site-specific exposure parameters from the baseline HHRA.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 15 of 17	draft ROD SWP Tables G1-G13 -HH-073117.xls

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ROD RISK WORKSHEET

Table G-12







Risk Characterization Summary

- Carcinogens







Scenario Timeframe: Future
Receptor Population: Resident
Receptor Age: Young Child/Adult

Medium

Exposure
Medium

Exposure Point

Chemical of
Concern

Carcinogenic Risk









Ingestion

Inhalation

Dermal

External
(Radiation)

Exposure
Routes Total

Groundwater

Tap Water

SWP-Wide

Benzene

Dichlorobenzene, 1,4-
Dichloroethane, 1,1-
Dichloroethane, 1,2-
Dioxane, 1,4-
Ethylbenzene
Methyl tert-Butyl Ether
Methylene Chloride
Tetrachloroethylene
Trichlorobenzene, 1,2,4-
Trichloroethane, 1,1,2-
Trichloroethylene
Vinyl Chloride

Benzo(a)pyrene
Naphthalene

PCBTEQ
Total PCBs

4,4'-DDD

4,4'-DDT

Aldrin

alpha-BHC

alpha-Chlordane

beta-BHC

Dieldrin

Lindane

gamma-Chlordane
Heptachlor
Heptachlor Epoxide

Arsenic

4E-05
3E-06
1E-04
9E-06
1E-04
2E-05
2E-06
1E-04
6E-05
7E-05
6E-07
4E-03
2E-01

3E-05

2E-04
8E-04

3E-06
2E-06
6E-05
3E-04
2E-06
1E-05
5E-06
9E-05
2E-06
4E-05
3E-05

9E-03

9E-05
8E-05
4E-04
4E-05
8E-05
6E-05
5E-06
8E-06
1E-04

2E-06
5E-03
8E-03

2E-03

7E-06
2E-06
8E-06
5E-07
4E-07
1E-05
5E-08
5E-06
4E-05
1E-04
4E-08
6E-04
1E-02

3E-05

1E-03
5E-04
1E-05
2E-05
3E-05
1E-04
1E-05
3E-04
1E-04

5E-05



1E-04
9E-05
5E-04
5E-05
2E-04
9E-05
7E-06
2E-04
2E-04
2E-04
3E-06
9E-03
2E-01

3E-05
2E-03

2E-04
8E-04

3E-05
2E-06
1E-03
7E-04
2E-05
3E-05
3E-05
2E-04
1E-05
4E-04
2E-04

9E-03

Groundwater Risk Total =

3E-01

Total Risk =

3E-01

Key

-- Route of exposure is not applicable to this medium.

N/A - Toxicity criteria are not available to quantitatively address this route of exposure.
PCB - Polychlorinated biphenyl.

TEQ - Toxicity equivalent.

This table provides risk estimates for the significant routes of exposure for the future young child and adult resident exposed to groundwater used as tap (household) water. These risk estimates are based on a reasonable
maximum exposure and were developed by taking into account various conservative assumptions about the frequency and duration of a young child's and adult's exposure to groundwater, as well as the toxicity of the
COCs (benzene, 1,4-dichlorobenzene, 1,1 -dichloroethane, 1,2-dichloroethane, 1,4-dioxane, ethylbenzene, methyl tert-butyl ether, methylene chloride, tetrachloroethylene, 1,2,4-trichlorobenzene, 1,1,2-trichloroethane,
trichloroethylene, vinyl chloride, benzo(a)pyrene, naphthalene, total PCBs, PCB TEQ, 4,4'-DDD, 4,4'-DDT, aldrin, alpha-BHC, chlordane, beta-BHC, dieldrin, lindane, heptachlor. heptachlor epoxide, and arsenic). The
total risk from direct exposure to contaminated groundwater to a future resident, in the event that SWP-Wide groundwater is used as a potable source, is estimated to be 3 x 10"1. The COCs contributing most to these risk
levels are trichloroethylene, vinyl chloride, naphthalene, aldrin, and arsenic in groundwater. This risk level indicates that if no clean-up action is taken, a future child/adult resident would have an increased probability of 3 in
10 of developing cancer as a result of site-related exposure to the COCs in groundwater. Results presented use current toxicity values along with site-specific exposure parameters from the baseline HHRA.

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 16 of 17	draft ROD SWP Tables G1 -G13 -HH-073117.xls

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ROD RISK WORKSHEET

Table G-13

Risk Characterization Summary - Non-Carcinogens

Scenario Timeframe: Future
Receptor Population: Resident
Receptor Age: Young Child/Adult

Medium

Exposure
Medium

Exposure Point

Chemical of
Concern

Primary Target Organ

Non-Carcinogenic Hazard Quotient











Ingestion

Inhalation

Dermal

Exposure
Routes Total

Groundwater

TapWater

SWP-Wide

Benzene

Dichloroethene, cis-1,2-
Methylene Chloride
Tetrachloroethylene
Trichlorobenzene, 1,2,3-
Trichlorobenzene, 1,2,4-
Trichloroethane, 1,1,2-
Trichloroethylene

Vinyl Chloride
Xylenes (total)

Immune System
Kidney
Liver
Nervous System
Endocrine/Liver
Endocrine/Liver
Liver/Respiratory
Cardiovascular/Developmental/
Endocrine/Immune System
Liver
Nervous System

9E-01
1E+03
2E+01
2E+01
4E+00
1E+00
1E-02
5E+02
6E+01
2E-01

9E-01

1E+00
2E+01

4E+01
2E+00
1E+03
1E+01
2E+00

1E-01
1E+02
6E-01
1E+01
6E+00
1E+00
8E-04
8E+01
4E+00
9E-02

2E+00
1E+03
2E+01
6E+01
1E+01
4E+01
2E+00

2E+03
7E+01
3E+00







C5-C8 Aliphatics
C9-C12 Aliphatics
C9-C10 Aromatics
C9-C18 Aliphatics
C11-C22 Aromatics

Nervous System/Respiratory
Blood/Kidney/Liver/Respiratory

Blood/Kidney
Blood/Kidney/Liver/Respiratory
Blood/Kidney

5E+00
6E-01
2E+00
9E-01
1E+00

4E+00
4E-01
5E+00
7E-01
3E+00

6E+00
5E+00
2E+00
1E+01
5E+00

1E+01
6E+00
9E+00
1E+01
9E+00







Methylnaphthalene, 2-
Naphthalene

Respiratory
Blood/Respiratory

1E+00
1E+00

1E+01
5E+01

2E+00
7E-01

2E+01
6E+01







PCB TEQ
Total PCBs

Developmental/Immune
System/Reproductive/Skin
Immune System/Skin

1E+01
8E+01





1E+01
8E+01







Aldrin
Lindane

Heptachlor Epoxide

Liver
Kidney/Liver
Liver

5E-01
1E+00
9E-01



9E+00
9E-01
6E-01

9E+00
2E+00
2E+00







Arsenic
Cobalt
Iron

Manganese

Developmental/Skin
Endocrine/Respiratory
Gl System
Nervous System

8E+01
3E+00
3E+00
1E+01



5E-01
9E-03
2E-02
2E+00

8E+01
3E+00
3E+00
2E+01

Groundwater Hazard Index Total =

3E+03

Skin Hazard Index =

2E+02

Immune System Hazard Index =

2E+03

Developmental Hazard Index =

2E+03

Kidney Hazard Index =

1E+03

Liver Hazard Index =

2E+02

Respiratory Hazard Index =

1E+02

Endocrine Hazard Index =

2E+03

Cardiovascular Hazard Index =

2E+03

Gl System Hazard Index =

3E+00

Nervous System Hazard Index =

9E+01

Blood Hazard Index =

9E+01

Key

N/A - Toxicity criteria are not available to quantitatively address this route of exposure
- Route of exposure is not applicable to this medium
PCB - Polychlorinated biphenyl
TEQ - Toxicity equivalent

This table provides hazard quotients (HQs) for each route of exposure and the hazard index (sum of the hazard quotients) for all routes of exposure for the future young child and adult resident exposed to groundwater used as tap
(household) water The Risk Assessment Guidance for Superfund (RAGS) states that, generally, a hazard index (HI) of greater than 1 indicates the potential for adverse noncancer effects The estimated target organ His between 3
and 2,000 indicate that the potential for adverse effects could occur from exposure to contaminated groundwater containing benzene, cis-1,2-dichloroethene, methylene chloride, tetrachloroethylene, 1,2,3-trichlorobenzene, 1,2,4-
trichlorobenzene, 1,1,2-trichloroethane, trichloroethylene, vinyl chloride, xylenes, C5-C8 aliphatics, C9-C12 aliphatics, C9-C10 aromatics, C9-C18 aliphatics, C11-C22 aromatics, 2-methylnaphthalene, naphthalene, PCB TEQ, total
PCBs, aldrin, lindane, heptachlor epoxide, arsenic, cobalt, iron, and manganese Results presented use current toxicity values along with site-specific exposure parameters from the baseline HHRA

Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)

Page 17 of 17	draftRODSWPTablesGl-Gl3-HH-073117.xls

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Table G-14

Occurrence, Distribution, and Selection of Chemicals of Potential Ecological Concern (COPECs)







Seasonally Ponded Area









Medium: Surface Water





Range of Detected

Average



COPEC? [c]









Frequency

Concentrations

(arithmetic

Final Selected



Maximum

Average HQ

Analyte

of Detection

mean) [a]

Benchmark [b]



Rationale [c]

HQ [d]

[e]

Metals, Total (mg/L)

















Aluminum

1; / ,3

0.244' - 0.244

0.169

0.087

Yes

ASL

2.8

1.9

Barium

3	/ 3

0.019 0.08b

0.0597

0.22

No

BSL

-

-

Calcium

3 / 3

14.8 BI.O

42.4

116

No

BSL

-

-

Chromium

3 / ,3

0.0052 - 0.023

0.0114

0.105

No

BSL

-

-

Cobalt

2 / 3

0.001/ - 0.0026

0.0019

0.024

No

BSL

-

-

Cyanide

2 / ,3

0.000 - 0.009

0.006

0.0052

Yes

ASL

1.7

1.2

Iron

3 / 3

0.318 - 2.77

1.42

1.0

Yes

ASL

2.8

1.4

Magnesium

3 / ,3

2.49 - (ill

4.74

82.0

No

BSL

-

-

Manganese

3 / 3

0.063 - 0.545

0.275

0.120

Yes

ASL

4.5

2.3

Nickel

2 / ,3

0.0027 - 0.004

0.0027

0.0639

No

BSL

-

-

Potassium

3 / 3

3.35 10.3

7.95

53.0

No

BSL

-

-

Sodium

3 / ,3

21.7, - 82.0

54.2

680

No

BSL

-

-

Vanadium

2 / 3

0.001 I 0.002

0.0017

0.012

No

BSL

-

-

Metals. Dissolved (ma/Ll

















Barium

3 / 3

0.018 0.083

0.059

0.22

No

BSL

-

_

Calcium

3 / ,3

14.4 - 01.5

42.9

116

No

BSL

-

-

Chromium

3 / 3

0.0028 - 0.0055

0.0043

0.090

No

BSL

-

-

Cobalt

1 /?3

0.0018 0.0018

0.0015

0.024

No

BSL

-

-

Iron

3 / 3

0.259 - 2.84

1.39

1.0

Yes

ASL

2.8

1.4

Magnesium

3 / ,3

2.45 0.35

4.85

82.0

No

BSL

-

-

Manganese

3 / 3

0.000 - 0.548

0.278

0.120

Yes

ASL

4.6

2.3

Nickel

2 / ,3

0.0023 0.0038

0.0025

0.0637

No

BSL

-

-

Potassium

3 / 3

3.93 - 11.1

8.71

53.0

No

BSL

-

-

Sodium

3 / ,3

22.1 81.0

51.5

680

No

BSL

-

-

Vanadium

1 / 3

0.0017 - 0.0017

0.0015

0.012

No

BSL

-

-

Notes:

















[a] Average (arithmetic mean) was calculated using the detection limit for non detects.











[b] Screening benchmarks were selected in SLERA Table 4-5. Where applicable, benchmarks were adjusted based on measured hardness of 12.7 mg/L as CaC03.

[c] Chemical is selected as a chemical of potential ecological concern (COPEC) if the maximum detected concentration is greater than the screening benchmark.

ASL - Above Screening Level

















BSL - Below Screening Level. Not retained as COPEC.













[d] Maximum hazard quotient (HQ) is the maximum detected concentration divided by the screening benchmark. HQs are only calculated for COPECs.



[e] Average HQ is the average detected concentration divided by the screening benchmark.











mg/L - milligrams per liter

















-------
Table G-15

Occurrence, Distribution, and Selection of Chemicals of Potential Ecological Concern (COPECs)







Seasonally Ponded Area









Medium: Wetland Sediment





Range of Detected

Average



COPEC? [c]









Frequency

Concentrations

(arithmetic

Final Selected



Maximum

Average HQ

Analyte

of Detection



mean) [a]

Benchmark [b]



Rationale [c]

HQ [d]

[e]

Volatile Oraanics (ma/Ka)

















2-Butanone (MEK)

1 / 5

0.145i - 0.14:')

7.9

0.042

Yes

ASL

3.5

188

Acetone

1 / 5

0.48!) 0.48!)

8.0

0.010

Yes

ASL

49

802

Carbon disulfide

1 / 5

0.017! - 10.017

3.9

0.024

No

BSL

-

-

Ethylbenzene

2 / 5

0.007 - !>3

11

0.175

Yes

ASL

303

61

Ethylene dibromide

1 / 4

9.5 - 9.!)

2.5



Yes

NSL

NA

NA

Methyl tert-butyl ether

1 / 5

0.115 - 10.115

3.9



Yes

NSL

NA

NA

Toluene

1 / 5

0.14 - 0.14

2.0

1.22

No

BSL

-

-

Semivolatile Oraanics (ma/Kcrt

















2-Methylnaphthalene

1/10

0.042!) 0.042!)

0.80

0.020

Yes

ASL

2.1

40

2-Methylphenol

2' / 5

0.0051 jo.15

0.15

0.012

Yes

ASL

13

12

Acenaphthene

4 / Ti 1

0.019 - 10.15

1.2

0.007

Yes

ASL

21

174

Acenaphthylene

3: / 11

0.0181 ] - 0.025

1.3

0.006

Yes

ASL

4.2

210

Acetophenone

2 rl 5

2.4 4.9!)

1.8



Yes

NSL

NA

NA

Anthracene

3s / 11

0.23 - 0.!)2

1.3

0.057

Yes

ASL

9.1

23

Benzaldehyde

3; / *5

0.19 1.56

0.50



Yes

NSL

NA

NA

Benzo(a)anthracene

9r/ 11

0.32 - 3.1

1.3

0.108

Yes

ASL

29

12

Benzo(a)pyrene

9s / T11

0.38 3.3

1.3

0.150

Yes

ASL

22

9.0

Benzo(b)fluoranthene

8 11

0.38 - 2.9

1.3

10.4

No

BSL

-

-

Benzo(g,h,i)perylene

9 vl 11

0.135 4.6

1.6

0.170

Yes

ASL

27

9.5

Benzo(k)fluoranthene

9s / 11

0.19 - 3.3

1.5

0.240

Yes

ASL

14

6.3

Bis(2-ethylhexyl)phthalate

3; / >6

0.36 0.64

0.93

0.182

Yes

ASL

3.5

5.1

Carbazole

2' 1 4

0.12 - 0.23

0.31



Yes

NSL

NA

NA

Chrysene

9s / T11

0.47; - 3.6

1.4

0.166

Yes

ASL

22

8.3

Dibenz(a,h)anthracene

7: / , 11

0.068 - !1.3

0.66

0.033

Yes

ASL

39

20

Fluoranthene

9 vl 11

0.6 5.4

1.9

0.423

Yes

ASL

13

4.5

Fluorene

5s / !11

0.014 - ?0.7

1.2

0.077

Yes

ASL

9.1

15

lndeno(1,2,3-cd)pyrene

9 1 1

0.0725; - 3.2

1.4

0.200

Yes

ASL

16

7.0

Naphthalene

3\ / 11

0.046 - 0.0/4!)

1.1

0.176

No

BSL

-

-

Phenanthrene

5= / 11

0.27; - 1.85

1.5

0.204

Yes

ASL

9.1

7.4

Phenol

3: 7 ?5

0.19 - 10.1

2.2

0.049

Yes

ASL

206

44

Pyrene

9r/ 11

0.6 [5.7

1.9

0.195

Yes

ASL

29

9.8

PCBs (ma/Kcrt

















PCB Congeners

















PCB 105

5r / *5

0.00202 : 0.2445

0.062636



Yes

NSL

NA

NA

PCB 114

5s / 5

0.000116 0.0104/5

0.002680



Yes

NSL

NA

NA

PCB 118

5: / 5

0.00368 - 10.563

0.150706



Yes

NSL

NA

NA

PCB 123

5rl *5

0.000719; - 0.0/92/5

0.017287



Yes

NSL

NA

NA

PCB 126

5s / :5

0.000II5 - ;0.001515

0.000584



Yes

NSL

NA

NA

PCB 156/157

5: / 5

0.002024; - 0.0/438!)

0.021479



Yes

NSL

NA

NA

PCB 167

5 rl

0.0011 - 0.02449

0.007580



Yes

NSL

NA

NA

PCB 170

2 / 2

0.017; - 0.0356

0.026300



Yes

NSL

NA

NA

PCB 189

5: / " 5

0.000239 - 0.00314

0.001126



Yes

NSL

NA

NA

PCB 193/180

2' 1 2

0.0331; - 0.0641

0.048600



Yes

NSL

NA

NA

PCB 77

5s / ;5

0.000489 - 0.00/99!)

0.003093



Yes

NSL

NA

NA

PCB 81

3: / " 5

0.0000393; - 0.0018!)!)

0.000545



Yes

NSL

NA

NA

Z:\Data\WP\Letters\Wells G&H SWP 0U2\EPA\R0D\draft ROD July 31 2017\Appendix B-Tables\
draft ROD SWP Tables G14-G19 Eco -073117.xlsx, G-15 Sed Seasonal Pond

Page 2 of 8

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Table G-15

Occurrence, Distribution, and Selection of Chemicals of Potential Ecological Concern (COPECs)







Seasonally Ponded Area









Medium: Wetland Sediment





Range of Detected

Average



COPEC? [c]









Frequency

Concentrations

(arithmetic

Final Selected



Maximum

Average HQ

Analyte

of Detection



mean) [a]

Benchmark [b]



Rationale [c]

HQ [d]

[e]

Aroclor 1254

25: / 41

0.311: - 220

17

0.060

Yes

ASL

3,667

290

Aroclor 1260

15 / 39

0.109: - 450

17

0.060

Yes

ASL

7,500

277

Total PCBs

37! / r41

0.109: - 450

30

0.060

Yes

ASL

7,500

495

Pesticides (ma/Ka)

















4,4'-DDD

2r7 "5

0.0289: - 0.0462

4.0

0.0049

Yes

ASL

9.4

857

4,4'-DDE

2; 7 !5

0.0046 10.0077

4.0

0.0032

Yes

ASL

2.4

1,250

4,4'-DDT

3:7 >5

0.0171: - 0.0924

4.0

0.0042

Yes

ASL

22

960

alpha-Chlordane

3r/ 3

0.00/2 0.03:59

0.021

0.0032

Yes

ASL

11

6.7

gamma-Chlordane

3; 7 3

0.013 - 0.0523

0.039

0.0032

Yes

ASL

16

12

Inoraanics (ma/Ka)

















Aluminum

5=7 5

10,700: - 23,500

15,370

25,500

No

BSL

-

-

Antimony

5: 7 *5

1.1 117

25

2.00

Yes

ASL

59

12

Arsenic

5' 1 1

5.6 - 17

11

9.79

Yes

ASL

1.7

1.1

Barium

5 s / 5

135 500

319



Yes

NSL

NA

NA

Beryllium

3: 7 *5

0.58: - 1.0

0.70



Yes

NSL

NA

NA

Cadmium

5 rl 7

1.1 4.5

2.3

0.99

Yes

ASL

4.5

2.3

Calcium

5s / 5

3.940 - 23,000

10,120



Yes

NSL

NA

NA

Chromium

45 45

48 66,500

5,893

43.4

Yes

ASL

1,532

136

Chromium (VI)

31 46

2.2 - :365.8

30



Yes

NSL

NA

NA

Cobalt

5r/ " 5

8.19 12

9.6

50.0

No

BSL

-

-

Copper

5:7 ?5

43 - 160

81

31.6

Yes

ASL

5.1

2.5

Cyanide

417 :7

0.3 2.28

1.0

0.100

Yes

ASL

23

10

Iron

5:7 "5

14,500: - 28.300

21,960

20,000

Yes

ASL

1.4

1.1

Lead

43 43

/'() 135,100

2,955

35.8

Yes

ASL

980

83

Magnesium

5rl ;5

4,370 - ;7,050

5,570



Yes

NSL

NA

NA

Manganese

5s / t5

176: - 7380

283

460

No

BSL

-

-

Mercury

3:7 5

0.18 - 1.13

0.43

0.18

Yes

ASL

6.3

2.4

Nickel

5 rl 15

25: - 41.5

30

22.7

Yes

ASL

1.8

1.3

Potassium

5s / !5

1360 6.400

3,497



Yes

NSL

NA

NA

Selenium

2:7 t5

0.255 - 0.51

0.81

2.00

No

BSL

-

-

Silver

2' 1 ]5

0.17: - 0.32

0.43

0.50

No

BSL

-

-

Sodium

3s / t5

180 - 880

400



Yes

NSL

NA

NA

Thallium

1: / 5

0.19 0.19

0.27



Yes

NSL

NA

NA

Vanadium

5 rl 15

36: - ;67.5

45



Yes

NSL

NA

NA

Zinc

5> 1 !5

307.5: - 92:5

577

121

Yes

ASL

7.6

4.8

Notes:

[a]	Average (arithmetic mean) was calculated using the detection limit for non-detects.

[b]	Screening benchmarks were selected in SLERA Table 4-6.

[c]	Chemical is selected as a chemical of potential ecological concern (COPEC) if the maximum detected concentration is greater than the screening benchmark
or a screening benchmark is unavailable.

ASL - Above Screening Level

BSL - Below Screening Level. Not retained as COPEC.

NSL - No Screening Level

[d]	Hazard quotient (HQ) is the maximum detected concentration divided by the screening benchmark. HQs are only calculated for COPECs.

[e]	Average HQ is the average detected concentration divided by the screening benchmark.

NA - Hazard quotient not calculated because benchmark not available.

Z:\Data\WP\Letters\Wells G&H SWP OU2\EPA\ROD\draft ROD July 31 2017\Appendix B-Tables\
draft ROD SWP Tables 014-019 Eco -073117.xlsx, 0-15 Sed Seasonal Pond

Page 3 of 8

-------
Table G-15

Occurrence, Distribution, and Selection of Chemicals of Potential Ecological Concern (COPECs)

Seasonally Ponded Area

Medium: Wetland Sediment

Analyte

Frequency
of Detection

Range of Detected
Concentrations

Average
(arithmetic
mean) [a]

Final Selected
Benchmark [b]

COPEC? [c]

Rationale [c]

Maximum
HQ [d]

Average HQ
[e]

mg/Kg - milligram per kilogram

Z:\Data\WP\Letters\Wells G&H SWP OU2\EPA\ROD\draft ROD July 31 2017\Appendix B-Tables\
draft ROD SWP Tables G14-G19 Eco -073117.xlsx, G-15 Sed Seasonal Pond

Page 4 of 8

-------
Table G-16

Occurrence, Distribution, and Selection of Chemicals of Potential Ecological Concern (COPECs)

Forested/Shrub Area

Medium: Wetland Surface Soil





Range of Detected

Average



COPEC? [c]









Frequency

Concentrations

(arithmetic

Final Selected



Maximum

Average HQ

Analyte

of Detection



mean) [a]

Benchmark [b]



Rationale [c]

HQ [d]

[e]

PCBs (ma/Ka)

















Aroclor 1254

6 / 13

0.4 - 15

2.2

0.00033

Yes

ASL

45,455

6,576

Aroclor 1260

8]' / 14

0.2 t7.9

1.7

0.00033

Yes

ASL

23,939

5,212

Total PCBs

14 / ] 14

0.2 15

3.0

0.00033

Yes

ASL

45,455

9,091

Inoraanics (ma/Ka)

















Aluminum

1: / M

5,500 - 5,500

5,500

pH < 5.5

No

BSL

-

-

Arsenic

1 / 2

12 - 12

16

18

No

BSL

-

-

Barium

1 r /11

4B - 46

46

330

No

BSL

-

-

Beryllium

i] / ii

0.24 - 0.24

0.24

21

No

BSL

-

-

Cadmium

117 M

0.7; - :o.7

0.70

0.36

Yes

ASL

1.9

1.9

Calcium

1 f/ ]2

2.200 - 2,200

1,100



Yes

NSL

NA

NA

Chromium

IB IB

45.1; - 62,500

4,928

26

Yes

ASL

2,404

190

Chromium (VI)

10 IB

2.09 - !343.75

27

130

Yes

ASL

2.6

0.21

Cobalt

1! / M

2.4 2.4

2.4

13

No

BSL

-

-

Copper

117 i

19 19

19

28

No

BSL

-

-

Cyanide

1:7 f2

0.31 0.31

0.63

1.33

No

BSL

-

-

Iron

1| / M

15,000 - 115,000

15,000

pH < 5.0

No

BSL

-

-

Lead

14 14

30 3,300

736

11

Yes

ASL

300

67

Magnesium

1! / M

420* - 420

420



Yes

NSL

NA

NA

Manganese

117 i

150- 150

150

220

No

BSL

-

-

Mercury

1:7 T1

0.2 - 0.2

0.20

0.10

Yes

ASL

2.0

2.0

Nickel

1!'/ i

8.4 - 8.4

8.4

38

No

BSL

-

-

Potassium

1 ]'"/ "h

180* - 180

180



Yes

NSL

NA

NA

Selenium

1! / M

0.99 0.99

0.99

0.52

Yes

ASL

1.9

1.9

Silver

117 i

0.16 - 0.16

0.16

4.2

No

BSL

-

-

Sodium

1:7 M

85' - 85

85



Yes

NSL

NA

NA

Thallium

1: / 1

0.072* - 0.0/2

0.072

0.057

Yes

ASL

1.3

1.3

Vanadium

1: / M

11: - 11

11

7.8

Yes

ASL

1.4

1.4

Zinc

11 / :1

140 - 140

140

46

Yes

ASL

3.0

3.0

Notes:

[a]	Average (arithmetic mean) was calculated using the detection limit for non-detects.

[b]	Screening benchmarks were selected in SLERA Table 4-7.

[c]	Chemical is selected as a chemical of potential ecological concern (COPEC) if the maximum detected concentration is greater than the screening benchmark or a
screening benchmark is unavailable.

ASL - Above Screening Level

BSL - Below Screening Level. Not retained as COPEC.

NSL - No Screening Level

[d]	Hazard quotient (HQ) is the maximum detected concentration divided by the screening benchmark. HQs are only calculated for COPECs.

[e]	Average HQ is the average detected concentration divided by the screening benchmark.

NA - Hazard quotient not calculated because benchmark not available.
mg/Kg - milligram per kilogram

Z:\Data\WP\Letters\Wells G&H SWP OU2\EPA\ROD\draft ROD July 31 2017\Appendix B-Tables\
draft ROD SWP Tables 014-019 Eco -073117.xlsx, 016 SS Forest-Shrub

Page 5 of 8

-------
AECOM

Table K-1

Comparative Analysis of Remedial Alternatives
Record of Decision

Wells G&H Superfund Site, Southwest Properties, OU4
Woburn, MA

MEDIUM

Overall Protection of
Human Health and
the Environment

Compliance with
ARARs

Long-Term
Effectiveness and
Permanence

Reduction of
Toxicity, Mobility,
or Volume Through
T reatment

Short-Term
Effectiveness

Implementability

COSTS

Capital Costs

Annual O&M
Costs

Present Worth

(1)

WHITNEY SOILS (SW)

Alternative SW-1: No Action

~

~

~

~

~~~

~~~

$0

$0

$0

Alternative SW-2: Capping and Institutional Controls

¦

~

~~

~

~~

~~~

$1,435,250

$357,359

$2,259,085

Alternative SW-3: Soil Excavation, Off-site Disposal, Capping, and Institutional Controls

¦

¦

~~~

~~

~~

~~~

$5,284,786

$371,552

$6,977,534

Alternative SW-4: Soil Excavation, Cover, Off-Site Disposal, and Institutional Controls

¦

¦

~~~

~~

~~

~~~

$7,579,985

$340,395

$9,815,375

MURPHY SOILS (SM)

Alternative SM-1: No Action

~

~

~

~

~~~

~~~

$0

$0

$0

Alternative SM-2: Capping and Institutional Controls

¦

~

~~

~

~~

~~~

$1,177,553

$284,828

$1,845,086

Alternative SM-3: Soil Excavation, Off-site Disposal, Capping and Institutional Controls

¦

¦

~~~

~~

~~

~~~

$2,009,381

$304,828

$2,967,258

Alternative SM-4: Soil Excavation, Cover, Off-Site Disposal, and Institutional Controls

¦

¦

~~~

~~

~~

~~~

$8,350,357

$340,395

$11,404,617

ABERJONA SOILS (SA)

Alternative SA-1: No Action

~

~

~

~

~~~

~~~

$0

$0

$0

Alternative SA-2: Capping and Institutional Controls

¦

~

~~

~

~~

~~~

$111,800

$10,470

$158,605

Alternative SA-3: Soil Excavation, Off-site Disposal, Capping, and Institutional Controls

¦

¦

~~~

~~

~~

~~~

$247,930

$85,470

$413,977

Alternative SA-4: Soil Excavation, Off-Site Disposal, and Institutional Controls

¦

¦

~~~

~~

~~

~~~

$400,201

$95,000

$625,266

GROUNDWATER (GW)

Alternative GW-1: No Action

~

~

~

~

~~~

~~~

$0

$0

$0

Alternative GW-2: Institutional Controls

~

~

~

~

~~~

~~~

$0

$46,578

$46,578

Alternative GW-3: Monitored Natural Attenuation and Institutional Controls

~

~

~

~~

~~~

~~~

$1,132,757

$46,578

$1,462,525

Alternative GW-4: In Situ Biological Treatment and Institutional Controls

¦

¦

~~

~~

~~~

~~

$5,332,765

$46,578

$7,112,492

Alternative GW-5: In Situ Chemical Oxidation (ISCO) and Institutional Controls

¦

¦

~~

~~

~~

~~

$21,587,207

$46,578

$27,030,586

Alternative GW-6: Pump and Treat and Institutional Controls

¦

¦

~~~

~~~

~~~

~~~

$1,794,994

$1,791,434

$4,169,801

NAPL (LN)

Alternative N-1: No Action

~

~

~

~

~~~

~~~

$0

$0

$0

Alternative N-2: NAPL Skimming/Recovery and Institutional Controls

¦

¦

~~

~~

~~

~~

$538,730

$90,395

$763,807

Alternative N-3: Excavation and Off-site Disposal

¦

¦

~~~

~~

~~

~~~

$2,645,542

$130,000

$3,436,928

MURPHY WETLAND (WTL)

Alternative WTL-1: No Action

~

~

~

~

~~~

~~~

$0

$0

$0

Alternative WTL-2: Monitored Natural Recovery and Institutional Controls

~

~

~

~

~~~

~~~

$150,524

$30,395

$218,549

Alternative WTL-3: Capping, Wetland Mitigation, Monitoring, and Institutional Controls

¦

~

~~

~

~

~~~

$747,950

$46,578

$1,037,612

Alternative WTL-4: Shallow (1 foot) Excavation and Targeted Deeper (3 feet) Excavation, Off-Site
Disposal, Amended Cap, Wetland Restoration, Monitoring and Institutional Controls

¦

¦

~~

~~

~~

~~~

$1,341,660

$101,387

$1,879,086

Alternative WTL-5: Deep (3 feet) Excavation and Off-site Disposal, Backfill, and Wetland Restoration

¦

¦

~~~

~~

~~

~~~

$1,522,444

$275,000

$2,178,055

Notes:

~	Fails

~	Marginally passes
¦ Passes

Page 1 of 1

~ Low	(1) Present Worth = Capital Costs + O&M Costs + Contingency Costs. See Attachment 5 of this FS Report Addendum for Contingency Costs.

~~ Medium
~~~ Hiah

-------
Table L-1: Groundwater Cleanup Levels

Carcinogenic Chemical of
Concern

Cancer Classification

SWP-Wide Cleanup Level

pg/L

Basis

Benzene

A

5

MCL

Dichlorobenzene, 1,4-

NA

75

MCL

Dichloroethane, 1,1-

C

2.8

ILCR = 10"b (Residential)

Dichtoroethane, 1,2-

B2

5

MCL

Dbxane, 1,4-

Likely to be carcinogenic to humans

0.46

ILCR = 10"b (Residential)

Ethylbenzene

NA

700

MCL

Methyl tert-Butyl Ether

NA

14

ILCR = 10"b (Residential)

Methylene Chloride

Likely to be carcinogenic to humans

5

MCL

Tetrachtoroethene

Likely to be carcinogenic to humans

5

MCL

Trichlorobenzene, 1,2,4-

Likely to be carcinogenic to humans

70

MCL

Trichloroethane, 1,1,2-

C

5

MCL

Trichloroethene

Carcinogenic to Humans

5

MCL

Vinyl Chloride

A

2

MCL

Benzo(a)pyrene

B2

0.2

MCL

Naphthalene

C

0.17

ILCR = 10"b (Residential)

Total PCBs

B2

0.5

MCL

4,4'-DDD

B2

0.032

ILCR = 10"b (Residential)

4,4'-DDE

B2

0.046

ILCR = 10"b (Residential)

4,4'-DDT

B2

0.23

ILCR = 10"b (Residential)

Aldrin

B2

0.001

ILCR = 10"b (Residential)

alpha-BHC

B2

0.007

ILCR = 10"b (Residential)

alpha-Chtordane

B2

2

MCL

beta-BHC

C

0.025

ILCR = 10"b (Residential)

Dieldrin

B2

0.002

ILCR = 10"b (Residential)

Lindane

NA

0.2

MCL

gamma-Chbrdane

B2

2

MCL

Heptachlor

B2

0.4

MCL

Heptachbr Epoxide

B2

0.2

MCL









Arsenic

A

10

MCL

Cobalt

Likely to be carcinogenic to humans

6

HQ = 1 (Residential)

Non-Carcinogenic Chemical of
Concern

Target Endpoint

Bedrock C

eanup Level

pg/L

Basis

Benzene

Immune System

5

MCL

Dichbrobenzene, 1,4-

Liver

75

MCL

Dichbroethane, 1,1-

Kidney

2.8

ILCR = 10"b (Residential)

Dichbroethane, 1,2-

Kidney

5

MCL

Dichbroethene, 1,1-

Liver

7

MCL

Dichbroethene, cis-1,2-

Kidney

70

MCL

Dichbroethene, trans-1,2-

Immune System

100

MCL

Dioxane, 1,4-

Kidney/Liver

0.46

ILCR = 10"b (Residential)

Ethylbenzene

Kidney/Liver

700

MCL

Methylene Chbride

Liver

5

MCL

Tetrachloroethene

Nervous System

5

MCL

Trichbrobenzene, 1,2,3-

Endocrine/Liver

7

HQ = 1 (Residential)

Trichbrobenzene, 1,2,4-

Endocrine

70

MCL

Trichbroethane, 1,1,1-

Liver

200

MCL

Trichbroethane, 1,1,2-

Liver

5

MCL

Trichbroethene

Cardiovascular/Developmental/lmmune System

5

MCL

Vinyl Chbride

Liver

2

MCL

Xylenes (total)

Nervous System

10000

MCL









C5-C8 Aliphatics

Nervous System

880

HQ = 1 (Residential)

C9-Cl2Aliphatics

Bbod/Kidney/Liver

50

Reporting Limit

C9-ClOAromatics

Respiratory

130

HQ = 1 (Residential)

C9-C18 Aliphatics

Bbod/Kidney/Liver

100

Reporting Limit

C11-C22 Aromatics

Respiratory

100

Reporting Limit









Methylnaphthalene, 2-

Respiratory

36

HQ = 1 (Residential)

Naphthalene

Bbod

0.17

ILCR = 10"b (Residential)









Total PCBs

Immune System/Skin

0.5

MCL









4,4'-DDT

Liver

0.23

ILCR = 10"b (Residential)

Aldrin

Liver

0.001

ILCR = 10"b (Residential)

alpha-BHC

Liver

0.007

ILCR = 10"b (Residential)

alpha-Chbrdane

Liver

2

MCL

Dieldrin

Liver

0.002

ILCR = 10"b (Residential)

Lindane

Kidney/Liver

0.2

MCL

gamma-Chbrdane

Liver

2

MCL

Heptachbr

Liver

0.4

MCL

Heptachlor Epoxide

Liver

0.2

MCL









Arsenic

Skin

10

MCL

Cobalt

Endocrine

6

HQ = 1 (Residential)

Iron

GI System

14000

HQ = 1 (Residential)

Lead

Nervous System

15

MCL

Manganese

Nervous System

300

Health Advisory

Key

Health Advisory - Health Advisory on Manganese (EPA-822-R-04-003; January 2004)

See Attachment 2ot the 2017 FS Report Addendum tor cleanup level development and basis.

HI - Hazard Index

MCL - Maximum Contaminant Level

ILCR - Incremental Litetime Cancer Risk; 10"6 = 1 in 1,000,000
NA - Not applicable

Cancer Classiticatbn
A - Human carcinogen

B1 - Probable human carcinogen - Indicates that limited human data are available

B2 - Probable human carcinogen - indicates sufficient evidence in animals and inadequate or no evidence in humans
C - Possible human carcinogen
D - Not classifiable as a human carcinogen
E - Evidence of noncarcinogenicity

Page 1 of 4

draft ROD SWP Tables L1 - L4 -09012017.xls

-------
Table L-2: Soil Cleanup Levels for the Protection of Human Health



Carcinogenic Chemical of
Concern

Cancer Classification

Cleanup Level1

Basis1'2





mg/kg





Benzene

A

0 026

Leachab

ity (DAF = 10)

Dichlorobenzene, 1,4-

NA

0 72

Leachab

ity (DAF = 10)

Dichloroethane, 1,1-

C

0 008

Leachab

ity (DAF = 10)

Dichloroethane, 1,2-

B2

0 014

Leachab

ity (DAF = 10)

Dioxane, 1,4-

Likely to be carcinogenic to humans

0 05

Leachability (Reporting Limit)

Ethylbenzene

NA

78

Leachability (DAF = 10)

Methyl tert-Butyl Ether

NA

0 05

Leachability (Reporting Limit)

Methylene Chloride

Likely to be carcinogenic to humans

0 013

Leachability (DAF = 10)

Tetrachloroethene

Likely to be carcinogenic to humans

0 023

Leachability (DAF = 10)

Trichlorobenzene, 1,2,4-

Likely to be carcinogenic to humans

0 20

Leachability (DAF = 10)

Trichloroethane, 1,1,2-

C

0 016

Leachability (DAF = 10)

Trichloroethene

Carcinogenic to Humans

0 018

Leachability (DAF = 10)

Vinyl Chloride

A

0 007

Leachability (DAF = 10)









Trichloroethene

Carcinogenic to Humans

39

ILCR = 10'6 (Recreational User)

Vinyl chloride

A

0 10

ILCR = 10'6 (Recreational User)









bis(2-Ethylhexyl)phthalate

B2

170

ILCR = 10'° (Recreational User)

Naphthalene

C

0 026

Leachability (Reporting Limit)









alpha-Chlordane

B2

80

ILCR = 10'° (Recreational User)

gamma-Chlordane

B2

80

ILCR = 10'° (Recreational User)

alpha-BHC

B2

0 39

ILCR = 10'° (Recreational User)

Heptachlor

B2

0 69

ILCR = 10'° (Recreational User)

Heptachlor Epoxide

B2

0 34

ILCR = 10'° (Recreational User)

Dieldrin

B2

0 15

ILCR = 10'° (Recreational User)

4,4-DDD

B2

10

ILCR = 10'° (Recreational User)

4,4-DDT



85

ILCR = 10'°(Recreational User)









Total PCBs

B2

53

HQ= 1 (Recreational User)









Arsenic

A

30

ILCR = 10'°(Recreational User)

Chromium (VI)

A

14

ILCR = 10'° (Recreational User)









Non-Carcinogenic Chemical of
Concern

Target Endpoint

Cleanup Level1

Basis1'2





mg/kg





Benzene

Immune System

0 026

Leachability (DAF = 10)

Dichlorobenzene, 1,4-

Liver

0 72

Leachability (DAF = 10)

Dichloroethane, 1,1-

Kidney

0 008

Leachability (DAF = 10)

Dichloroethane, 1,2-

Kidney

0 014

Leachability (DAF = 10)

Dichloroethene, 1,1-

Liver

0 025

Leachability (DAF = 10)

Dichloroethene, cis-1,2-

Kidney

0 21

Leachability (DAF = 10)

Dichloroethene, trans-1,2-

Immune System

031

Leachability (DAF = 10)

Dioxane, 1,4-

Kidney/Liver

0 05

Leachability (Reporting Limit)

Ethyl benzene

Kidney/Liver

78

Leachab

ity (DAF = 10)

Methylene Chloride

Liver

0013

Leachab

ity (DAF = 10)

Tetrachloroethene

Nervous System

0 023

Leachab

ity (DAF = 10)

Trichlorobenzene, 1,2,3-

Endocrine/Liver

0 12

Leachab

ity (DAF = 10)

Trichlorobenzene, 1,2,4-

Endocrine

0 20

Leachab

ity (DAF = 10)

Trichloroethane, 1,1,1-

Liver

0 70

Leachab

ity (DAF = 10)

Trichloroethane, 1,1,2-

Liver

0016

Leachab

ity (DAF = 10)

Trichloroethene

Cardiovascular/Developmental/lmmune System

0018

Leachab

ity (DAF = 10)

Vinyl Chloride

Liver

0 007

Leachab

ity (DAF = 10)

Xylenes (total)

Nervous System

98

Leachab

ity (DAF = 10)









Trichloroethene

Cardiovascular/Developmental/lmmune System

39

ILCR = 10°(Recreational User)

Vinyl chloride

Liver

0 10

ILCR = 10 ° (Recreational User)









C5-C8 Aliphatics

Nervous System

88

Leachability (DAF = 10)

C9-C12 Aliphatics

Blood/Kidney/Liver

15

Leachability (DAF = 10)

C9-C10Aromatics

Respiratory

27

Leachability (Reporting Limit)

C9-C18 Aliphatics

Blood/Kidney/Liver

15

Leachability (DAF = 10)

C11-C22 Aromatics

Respiratory

6 4

Leachability (Reporting Limit)









bis(2-Ethylhexyl)phthalate

Liver

170

ILCR = 10°(Recreational User)

Methylnaphthalene, 2-

Respiratory

1 9

Leachability (DAF = 10)

Naphthalene

Blood

0 026

Leachability (Reporting Limit)









alpha-Chlordane

Liver

80

ILCR = 10 ° (Recreational User)

gamma-Chlordane

Liver

80

ILCR = 10" (Recreational User)

alpha-BHC

Liver

0 39

ILCR = 10 ° (Recreational User)

Heptachlor

Liver

0 69

ILCR = 10 ° (Recreational User)

Heptachlor Epoxide

Liver

0 34

ILCR = 10 ° (Recreational User)

Dieldrin

Liver

0 15

ILCR = 10 ° (Recreational User)

4,4-DDT

Liver

85

ILCR = 10 ° (Recreational User)









Total PCBs

Immune System/Skin

5 3

HQ = 1 (Recreational User)









Arsenic

Skin

30

ILCR = 10 ° (Recreational User)

Chromium (VI)

Gl System

14

ILCR = 10 ° (Recreational User)

Thallium

Skin

35

HQ= 1 (Recreational User)









Key









NA - Not applicable









SSL - Soil Screening Level









DAF- Dilution Attenuation Factor









MCL - Maximum Contaminant Level









1 See Attachment 2 of the 2017 FS Report Addendum for cleanup level development and basis







ILCR - Incremental Lifetime Cancer Risk, 10'6 = 1 in 1,000,000 and 10'5 = 1 in 100,000







HQ - Hazard Quotient









Leachability - MCL-based SSLs provided on the November 2016 Regional Screening Level table (ILCR = 10'6, HQ =

), multiplied by 10



for a DAF =10 If no MCL-based SSL was available on the RSL table, the risk-based SSL was used after being multiplied by 10 for DAF

10

2 Cleanup levels based on leachability are applicable to soils above the water table only Risk-based cleanup levels are applicable to soils to a depth of 15 feet

Leachability values are applicable to all three properties, risk-based cleanup values are applicable to the Whitney Property,



except for thallium which is only applicable to the Murphy Property







Cancer Classification









A - Human carcinogen









B1 - Probable human carcinogen - Indicates that limited human data are available







B2 - Probable human carcinogen - indicates sufficient evidence in animals and inadeguate or no evidence in humans





C - Possible human carcinogen









D - Not classifiable as a human carcinogen









E - Evidence of noncarcinogenicity









Page 2 of 4	draft ROD SWP Tables L1 - L4 -09012017.xls

-------
Table L-3: Wetland Sediment/Soil Cleanup Levels for the Protection of Human Health (Murphy Wetland)



Carcinogenic Chemical of
Concern

Cancer Classification

Cleanup Level1

Basis1





mg/kg



Total PCBs

B2

8.4

HQ = 1 (Recreational User)









Non-Carcinogenic Chemical of
Concern

Target Endpoint

Cleanup Level1

Basis1





mg/kg



C11-C22 Aromatics

Blood

14,000

HQ = 1 (Recreational User)









Total PCBs

Immune System/Skin

8.4

HQ = 1 (Recreational User)









Lead

Nervous System

570

IEUBK Model









Key







NA - Not applicable







1. See Attachment 2 of the 2017 FS Report Addendum for cleanup level development and basis:



HQ - Hazard Quotient







Cancer Classification







A - Human carcinogen







B1 - Probable human carcinogen - Indicates that limited human data are available





B2 - Probable human carcinogen - indicates sufficient evidence in animals and inadequate or no evidence in humans



C - Possible human carcinogen







D - Not classifiable as a human carcinogen







E - Evidence of noncarcinogenicity







Page 3 of 4

draft ROD SWP Tables L1 - L4 -09012017.xls

-------
Table L-4: Wetland Sediment/Soil Cleanup Levels for the Protection of Ecological Receptors (Murphy Wetland)



Habitat
Type/Name

Exposure
Medium

COC

Protective
Level

Units

Basis

Assessment
Endpoint

PROPOSED CLEANUP LEVEL

Seasonally Ponded Area

Wetland Sediment

Total PCBs (Aroclors)

1.9

mg/kg

Shrew Site-Specific MATC "

All Receptor Endpoints

Chromium

130

mg/kg

Mean Background Concentration

Lead

330

mg/kg

Mean Background Concentration

Zinc

460

mg/kg

Benthic PEC

Forested/Shrub Area

Wetland Soil

Total PCBs (Aroclors)

1.3

mg/kg

Shrew Site-Specific MATC (1)

Survival and reproduction of
insectivorous mammal population

Chromium

1900

mg/kg

Shrew Site-Specific MATC (1)

Notes:

(1) The site-specific MATC (set as the geometric mean between the NOAEL and LOAEL values) has been selected as the protective level for each COC for the muskrat and shrew.

COC - Chemical of Concern

PEC - Probable Effect Concentration

NOAEL - No observed adverse effect level.

LOAEL - Lowest observed adverse effect level.

MATC - Maximum Acceptable Toxic Concentration .

-------
Table L-5. Cost Summary for EPA's Selected Remedy

Alternative

Capital Cost

(construction)
(millions)

Contigency

(millions)

O&M

(millions)

Total Cost (construction,
contigenc and O&M) (millions)

SW-3/SM-3/SA-3 - Soil
Excavation, Off-Site
Disposal, Capping and
Institutional Controls

$7.5

$2.1

$0.76

$10.4

GW-6 - Pump and Treat
and Institutional Controls

$1.8

$0.58

$1.8

$4.2

N-3 - Excavation and Off-
Site Disposal(1)

$1.8

$0.44

$0.13

$2.3

WTL-5 - Deep Excavation
and Off-Site Disposal,
Backfill, and Wetland
Restoration

$1.5

$0.38

$0.28

$2.2

Overall Cost for Preferred Options

$19.1

Notes

(1) Cost for Alterative N-3 has been adjusted downward because Alternative SW-3 includes excavation
within the area where NAPL is present on the Whitney Property.

-------
Appendix C: Figures

-------
routes

OLYMPIA

i^Aberjona River

wildwqIqd:
property'

Aberjona
Auto Parts

Whitney
Barrel



Murphy's



Waste Oil

FIGURE A-1
SOUTHWEST PROPERTIES
(SWP), OPERABLE UNIT 4

(OU4) LOCATION
WITHIN THE WELLS G&H
SUPERFUND SITE

® Wells G&H
L Site Boundary
I I Southwest Properties, OU4
Wetland

2,000

Feet

Source Data: MassGIS

R:\Projects\GIS_2017\170830-AECOM SW prop\mxd\Figure 6.mxd

-------
Figure E-1
Conceptual Site Model
Southwest Properties
Remedial Investigation

Property

Primary Source

Primary Contaminated Media

Primary
Transport
Mechanism

Primary Media

Secondary Release and Transport Mechanisms

Exposure
Media'3'

-------
RILEY WELL 2

Sewer Manhole

Former
Drairmne,

y

MW-4M

Murphy
Wetland

WB 201S
4/2011: 0 ft
10/2011:0.08 ft
7/2013: Globules

V\ *
MW-16. \ -
1/2011 >12/2013:
0.01 to 1*08 FT

FORMER WASTE! MW-3D
OILASTAREA \
(APfR« \ MV
MW-20^ \

MW-1

EORMER
boiler/

h	 1/2011 - 12/2013: R00M	_

SPOTTY OIL tov2.70 FT CONCRETE SLAB"^ V
\ \ ON GRADE
MW-25*	\ V

1/2011 - 12/2013: \	OVERHEAD DOORS

Oto 0.44 FT	\	(Tr P)

WOODEN ELOOR

DRUM/BARREL
STORAGE

WHITNEY
BARREL
PROPERTY
256 Salem St

MW-7

1/2011 - 12/2013:
Oto 0.45 FT

FORMER
PIT (AP|F

Oil
Recycling
Building I

MR 206
4/2011: 0 FT
10/2011: SHEEN
7/2013: SHEEN

Legend

Approximate extent of LNAPL
(Dashed Where Inferred)

Wetland

Building

250 SALEM ST

Sewer Line
Property Line
Road

Railroad

AECOM

-0- Intermediate/Deep Overbuden Well
Shallow Overburden Well
Bedrock Groundwater Well

Data as reported for 2011-2013 Rl activities,
and in the Immediate Response Action Status
Report, dated February 6, 2015 (Clean Harbors, 2015

FIGURE E-2
OVERVIEW OF
NAPL IMPACTS

-------
MWRA SEWER
% EASEMENT

CITY OF WOBURN
SEWER EASEMENT

WILDWOOD
PROPERTY

ABERJONA
AUTO PARTS
PROPERTY
270 & 280 Salem St

TREATMENT BUILDING

285 SALEM ST

FORMER SHED
(APPROX)

1978 ADDITION

1968 ADDITION

Sewer Manhole

FLOOR DRAIN

FORMER WASTE
OIL TANK

ABERJONA
kRESIDENGfi

FORMER
DIESEL USlY
OIL/WATER
^SEPERATOR>

^^ORESTED/SCRUB-SHRUB'SWAMP

Murphy .
Wetland.

' Former
Drain Line

283 SALEM

,R£A0F FpRMER
iASOLJNE PUMP

REPORTED ARE/
FORMER GASQt?
USTS (APPROX)

ICE RINK

FORMER WATEF
OIL AST AREA
l (APPROX.)

& Former^N^C
vfekBoiler Room
Concrete Slab on Grade^.
Vy Ove rhead^
Doors (TYP)S(

fjwwsfttj Wooden Floor"
" 'm^a#ub Drum/Barrel"
\| \ Storage

Approximate Limit
of Drainage Swale/
Organix Removal Action

275 SALEM ST

Equip^^ y
Storage

	Gravel Floortfc

Covered Area1

MURPHY WASTE
OIL PROPERTY
250 & 252 SALEM ST

WHITNEY
BARREL
PROPERTY
256 SALEM ST.

I Oil |f—
Recycling
Building^

263 SALEM ST

FORMER OIL
PIT (APPROX.)

271 SALEM

Legend

i—i Culvert (Approximate Location)

	Building

= Cap Limit
Fence

Property Line
Railroad

248 \
SALEM
v ST

246 >
SALEM
ST .

FORMER

RILEY
TANNERY

Sewer Line

	Stream/Waterbody

—Wetland

r — — i

L 1 Disposal Site Limits
~ Historic Features

o_

oi

Wetland Area (Murphy Wetland)

Forested Scrub Shrub

Seasonally Ponded Area

WELLS G & H
SOUTHWEST PROPERTIES
WOBURN, MA

DATE: 7/5/2017

DRWN:

PROJECT 60312288

FIGURE E-3
SWP LAYOUT

-------
285 SALEM ST

>Sewer-!Manhole

FORESTED/SCRUB-SHRUB SWAMP

Murphy
Wetland

Former
Drain Line

283 SALEM STj

ICE RINK

\\ Former /
\yBoiler Room

\S

Concrete^SlablonlGrade;

Equip.
Storage

OverheaaJI
Doors (TYP)

275 SALEM ST

Gravel Floor
Covered Area

Wooden Floor

i foreste]

SCRUB-SHI
SWAM J

Drum/Barrel
Storage

WHITNEY
BARREL
PROPERTY
256 Salem St

i oii r

Recycling
\Building

263 SALEM ST

271 SALEM S

FIGURE E-4
FEMA FLOOD HAZARD

DATE: 6/30/2017

DRWN:

PROJECT 60312288

Note: Data from Flood Insurance Rate Maps (FIRM) Panel 25017C0407E, published by the
Federal Emergency Management Agency. Map Effective Date: June 3, 2010.

Shapefle Data Souce: MassGIS

WELLS G & H
SOUTHWEST PROPERTIES
WOBURN, MA

Legend

¦» Wetland
Building
Fence
Sewer Line
Property Line
Road
Railroad
Streams

FEMA National Flood Hazard Layer
Flood Zone Designations

100-Year Floodplain
rloodway

500-Year Floodplain

MURPHY WASTE
OIL PROPERTY
250 & 252 Salem St

-------
l8S8SS8K&H88SK3K

THALLIUM IMPACTED AREA

AREA OF SOIL EXCEEDING
LEACHING TO GROUNDWATER PRGs

FIGURE E-5
OVERVIEW OF SOIL
IMPACTS AT MURPHY

AsCOM

Legend

¦Property Line

wells G & H
SOUTHWEST PROPERTIES
WOBURN, MA

DATE: 8/16/2017 DRWN:

PROJECT 60312288

-------
FIGURE E-6
OVERVIEW OF SOIL IMPACTS
AT WHITNEY

AREA OF LOWER SOIL IMPACTS
(GENERALLY <10X PRCs)

Legend

¦Property Line

wells G & H
SOUTHWEST PROPERTIES
WOBURN, MA

DATE: 7/10/2017 DRWN

PROJECT 60312288

PCBs IN SOIL >10 pprn
(>10X PRGs)

HIGHEST LEVELS OF

VOCs, METALS, SVOCs
AND PESTICIDES IN SOIL

AREA WITH HIGHEST LEVEL

OF CVOCs IN GROUNDWATER
(>100X PRGs)

As.COM

-------
Q.
W
O
W

9

Q
Q
<
O

VOCs/PETROLEUM FRACTIONS
EXCEEDING LEACHING TO
GROUNDWTER PRGs

WELLS G & H
SOUTHWEST PROPERTIES
WOBURN, MA

Legend

KX/lCap Area 		'Property Line

FIGURE E-7
OVERVIEW OF SOIL IMPACTS
ATABERJONA

AECOM

DATE: 12/5/2016

DRWN

PROJECT 60312288

-------
-------
AECOM

Bedrock Well	Bedrock Exceedarices (Dashed Where Inferred)

¦ Intermediate/Deep Well II I Intermediate Exceedances
• Shallow Well	II I Shallow Exceedances

N

W-HSM-E

s

50

100
I Feet

WELLS G & H
SOUTHWEST PROPERTIES
WOBURN, MA

FIGURE E-9
OVERVIEW OF SWP-WIDE
GROUNDWATER IMPACTS

DATE: 12/7/2016 DRWN: J.E.B

PROJECT 60312288

-------
EXCAVATE NORTHERN WHITNEY SOIUXREATO
APPROXIMATELY 6-10 FT (8 FT AVENGE) INCLUDING
FORMER DRAIN LINE, REMOVE EXERTION OF BUILDING
AND CAP SEE FIGURE 5 /

REMOVE APPROXIMATELY 2 FEET
AND RELACE WITH CAP SEE FIGURE 5
FOR DETAILS

EXCAVATE TO APPROXIMATELY 15'
AND SOIL BLEND TO APPROXIMATELY 24'
SEE FIGURE 5

REMOVE APPROXIMATELY 2 FEET
AND RELACE WITH CAP SEE FIGURE 5
FOR DETAILS

Remove approximately 2 feet

AND RELACE WITH CAP SEE FIGURE 5
FOR DETAILS

Notes

1.	The horizontal and vertical extent of excavation and placement
of amended backfill will be determined based on pre-design
investigations and detailed design.

2.	The final location and design of the cap will be determined
based on pre-design investigations and detailed design.

3.	The"Cap Area" including the Murphy and Whitney Building
and portion of generally the Aberjona Building represents
the apporximate locations where soils exceed the PRGs.

4.	"REMOVE APPROXIMATELY 2 FEET" is to prevent flood
storage loss within the Floodplain.

Legend

Cap Area
R93 Excavation

Deeper Excavation
•Property Line

WELLS G & H
SOUTHWEST PROPERTIES
WOBURN, MA

DATE: 6/30/2017 DRWN

PROJECT 60312288

FIGURE L-1
CONCEPTUAL PLAN FOR SOIL
SM-3, SW-3 & SA-3 ALTERNATIVES

-------
MWRA SEWER
1 EASEMENT

CITY OF WOBURN
SEWER EASEMENT

WILDWOOD
PROPERTY

ABERJONA
AUTO PARTS
PROPERTY
270 & 280 Salem St

TREATMENT BUILDING

285 SALEM ST

EXCAVATION:
APPROXIMATELY
4145 SQ FT
WATER TABLE: 6 FT
EXCAVATE TO 12 FT

ABERJONA
J*SeiDENCE

Murphy .
Wetland.

283 SALEM

S4A,

EXCAVATION:
APPROXIMATELY
4145 SQ FT
WATER TABLE: 7 FT
EXCAVATE TO 12 FT

ICE RINK

275 SALEM ST

WHITNEY
BARREL
PROPERTY
256 SALEM ST

1 Oil
Recycling
Building^

263 SALEM ST

MURPHY WASTE
OIL PROPERTY
250 & 252 SALEM ST

EXCAVATION:
APPROXIMATELY
4975 SQ FT
WATER TABLE: 7 FT
EXCAVATE TO 12 FT

271 SALEM

Legend

Excavation Area

NAPL

	Building

= Cap Limit

Fence
— Property Line
Railroad
Road

Sewer Line

	Stream/Waterbody

—— Wetland

FORMER

RILEY
TANNERY

Notes:

(1)	Excavation areas to be refined as part
of pre-design investigation.

(2)	NAPL product or globules observed floating in monitoring wells

(3)	Approximately 2 feet of soil removed as part of Murphy SM-3 alternative

(4)	Whitney NAPL area removed as part of Whitney SW-3 alternative

o
o

CD

WELLS G & H
SOUTHWEST PROPERTIES
WOBURN, MA

DATE: 6/30/2017 DRWN

PROJECT 60312288

FIGURE L-2
CONCEPTUAL PLAN FOR NAPL
ALTERNATIVE N-3

-------
NAPTHALENE

WATER TRANFER LINES-

BENZENE

TREATMENT PLANT
(LOCATION TO BE DETERMINED)

ICE RINK

WHITNEY
BARREL
PROPERTY
256 Salem St

FIGURE L-3
CONCEPTUAL PLAN FOR GROUNDWATER
ALTERNATIVE GW-6

Notes

1.	Plume boundaries defined as where one or more
VOCs exceed PRGs. Source removal is assumed
as shown.

2.	Areas of VOCs impact above PRGs are approximate
based on data from existing monitoring well network.
The lateral and vertical extent of these areas will be
refined during pre-design investigation.

3.	Preliminary extraction well network design by EPA,

4.	Predesign investigation to define treatment areas
for all COCs.

5.	Final extraction well network to be determined based
on pumping tests and other predesign activities.

ABERJONA
AUTO PARTS
PROPERTY
270 & 280 Salem St

SALEM ST

MURPHYS WASTE OIL PROPERTY
250 & 252 SALEM STREET

275 SALEM ST

263 SALEM ST

271 SALEM ST

285 SALEM S"

WELLS G & H
SOUTHWEST PROPERTIES
WOBURN, MA

DATE: 6/30/2017 DRWN: J.E.B

PROJECT 60312288

WILDWOOD
PROPERTY

~ Bedrock



Proposed Extraction Wells Approximate location where
• Shallow	^^groundwater exceeds Volatile Organic

Compounds (VOCs) PRGs

¦ Intermediate

-------
4.



\

CP

'

\ \ "2v^ • - -,*"







/' *f x

\

\

ABERJONAAUTO PARTS

PROPERTY

270 & 280 SALEM ST.

19 78 ADDITION
FLOOR DRAIN





y

/



$an
sAfy

$an
sAN .

APPROXIMATE WEI
SEDIMENT/SOILS
EXCEEDING PRGS

Sam

APPROXIMATE EXCAVATE
AND CAP

+
i

+

SHRUB UPLAND

RESTORE TO ORIGINAL
GRADE AND REVEGETATE

EXCAVATE, BACKFILL TO
PRE-EXCAVATION ELEVATION
WITH AMENDED SOIL, AND
^ RESTORE

FORMER
BOILER.

ROOfv

CONCRETE SLAE
ON GRADE

OIL/WATER
SERERATOR

OVERHEAD DOORS'
(TYP)

WOODEN FLOOR

DRUM/BARREL
STORAGE



.ECU IP.
STORAGE

GRAVEL FLOOR
COVERED AREA

EXCAVATION DETAIL

Legend

	Building

= Cap Limit
Fence

Property Line
Railroad
Road
— Sewer Line
Stream
—¦¦¦ Wetland



t ^

T I
+ +

I i

I \

T I
{ +

* i

\ I
\ \

\ \
I *

t j-
* +

\ \
t i

* *
i *

t A-

u

WHITNEY
BARREL
PROPERTY
256 Salem St

MURPHY WASTE OIL

PROPERTY

250 & 252 SALEM ST

Clean Harbors sampling locations were digitized from print maps and are approximate
	/ \	



Legend

[Approximate Excavate and Restore Area
Wetland Sample Location Exeeding PRGs

Note:

1) Preliminary Remediation Goals

25

50

I Feet

WELLS G & H
SOUTHWEST PROPERTIES
WOBURN, MA

DATE: 6/30/2017 DRWN

PROJECT 60312288

FIGURE L-4
CONCEPTUAL PLAN FOR WETLAND
ALTERNATIVE WTL-5

-------
2" WEARING COURSE

s

I

Ci

J

a-

a*

EXCAVATE AND BACKFILL
WITH AMENDMENT

DETAIL A

SLOPE TO EXISTING STORMWATER DRAINAGE

WOVEN GEOTEXTILE



APPROXIMATELY
2'

6" ASPHALT
6" SUBBASE STONE

WOVEN GEOTEXTILE

WATER
TABLE

GEOTEXTILE
MARKER LAYER

EXCAVATION
6-15 FEET

TEMPORARY
SHORING

DEEP SOIL MIXING
TO 24' IN AREA OF
BORING WB 201

NONWOVEN
GEOTEXTILE

GEOCOMPOSITE

40 MIL HDPE
MEMBRANE

UNDISTURBED
SOIL

CRUSHED STONE

PERFORATED HDPE
CORRUGATED PIPE
(SLOPED TO STORMWATER FEATURE)

1* OVERLAP

EXCAVATE 2' AND MEMBRANE CAP
WITH ASPHALT SURFACE

MAINTAIN EXISTING SLOPE TO THE EXTENT PRACTICABLE

GRASS



APPROXIMATELY
2'

NONWOVEN
GEOTEXTILE

GEOCOMPOSITE

40 MIL HDPE
MEMBRANE

UNDISTURBED

CRUSHED STONE

4" PERFORATED HDPE
CORRUGATED PIPE
^SLOPED TO STORMWATER FEATURE)

1' OVERLAP

EXCAVATE 2' AND MEMBRANE CAP
WITH GRASS SURFACE

DETAIL B

WELLS G & H
SOUTHWEST PROPERTIES
WOBURN, MA

FIGURE L-5
CONCEPTUAL FILL/CAP DESIGNS

DATE: 6/29/2017

DRWN: JB

-------
Appendix D: ARARs Tables

-------
Table D-l

Chemical-Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Off-site Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Guidelines for
Carcinogenic Risk
Assessment

EPA/630/P-
03/001F

To Be
Considered

These guidelines provide guidance on
conducting risk assessments involving
carcinogens.

Partial excavation and off-site disposal, capping, and
institutional controls (ICs) would prevent exposure to soil
contaminants which contribute to a calculated
carcinogenic risk, developed using this guidance. Long-
term monitoring and ICs will ensure the protectiveness of
the caps and prevent residential development.

Supplemental Guidance
for Assessing
Susceptibility from Early-
Life Exposure to
Carcinogens

EPA/630/R-
03/003F

To Be
Considered

This provides guidance on assessing risk to
children from carcinogens.

Partial excavation and off-site disposal, capping, and ICs
would prevent exposure to soil contaminants which
contribute to a calculated carcinogenic risk to children,
developed using this guidance. Long-term monitoring and
ICs will ensure the protectiveness of the caps and prevent
residential development.

EPA Risk Reference
Doses (RfDs)



To Be
Considered

Guidance used to compute human health
hazard resulting from exposure to non-
carcinogens in site media. RfDs are
considered to be the levels unlikely to cause
significant adverse health effects associated
with a threshold mechanism of action in
human exposure for a lifetime.

Partial excavation and off-site disposal, capping, and ICs
would prevent exposure to soil contaminants which
contribute to a calculated non-carcinogenic risk,
developed using this guidance. Long-term monitoring and
ICs will ensure the protectiveness of the caps and prevent
residential development.

Human Health
Assessment Cancer
Slope Factors (CSFs)



To Be
Considered

CSFs are estimates of the upper-bound
probability of an individual developing
cancer as a result of a lifetime exposure to a
particular concentration of a potential
carcinogen.

Partial excavation and off-site disposal, capping, and ICs
would prevent exposure to soil contaminants which
contribute to a calculated carcinogenic risk, developed
using this guidance. Long-term monitoring and ICs will
ensure the protectiveness of the caps and prevent
residential development.

EPA Carcinogenic
Assessment Group
Potency Factors



To Be
Considered

These factors are used to evaluate an
acceptable risk from a carcinogen.

Partial excavation and off-site disposal, capping, and ICs
would prevent exposure to soil contaminants which
contribute to a calculated carcinogenic risk, developed
using this guidance. Long-term monitoring and ICs will
ensure the protectiveness of the caps and prevent
residential development.

1

-------
Table D-l

Chemical-Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Off-site Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Updated Scientific
Considerations for Lead
in Soil Cleanups

EPA OLEM

Directive

9200.2-167

To Be
Considered

EPA Guidance for evaluating risks posed by
lead in soil. Used to develop site-specific
risk-based standards. Recommends
evaluating potential risks from exposures to
lead at a Superfund site at a target blood
lead level lower than 10 [jg/dL.

Partial excavation and off-site disposal, capping, and ICs
would prevent exposure to lead-contaminated soil which
contributes to a calculated risk, developed using this
guidance. Long-term monitoring and ICs will ensure the
protectiveness of the caps and prevent residential
development.

Recommendations of
the Technical Review
Workgroup for Lead for
an approach to
Assessing Risks
Associated with Adult
Exposure to Lead In Soil

EPA-540-
R-03-001
(January
2003)

To Be
Considered

EPA Guidance for evaluating risks posed by
lead in soil.

Partial excavation and off-site disposal, capping, and ICs
would prevent exposure to lead-contaminated soil which
contributes to a calculated risk, developed using this
guidance. Long-term monitoring and ICs will ensure the
protectiveness of the caps and prevent residential
development.

Guidance on Remedial
Actions for Superfund
Sites with Polychlorinated
Biphenyl (PCB)
Contamination

EPA-540-
G-90-007
(August
1990)

To Be
Considered

EPA Guidance for evaluating risks posed by
PCBs at Superfund sites. Used to develop
risk-based cleanup standards.

Partial excavation and off-site disposal, capping, and ICs
would prevent exposure to PCB soil contaminants which
contribute to a calculated risk, developed using this
guidance. Long-term monitoring and ICs will ensure the
protectiveness of the caps and prevent residential
development.

Supplemental Guidance
for Developing Soil
Screening Levels for
Superfund Sites.

OSWER

9355.4-24

(2002)

To Be
Considered

EPA Guidance for evaluating soil
contamination. Used to develop soil
contaminant leachability cleanup standards.

This alternative would prevent leaching of soil
contaminants to groundwater through either
removal/disposal or placing impermeable caps over all
soil contamination left in place that poses a leachability
risk to groundwater, based on standards developed using
this guidance.

Soil Screening Guidance:
Technical Background
Document.

EPA/540/R

95/128

(1996)

To Be
Considered

EPA Guidance for evaluating soil
contamination. Used to develop soil
contaminant leachability cleanup standards.

This alternative would prevent leaching of soil
contaminants to groundwater through either
removal/disposal or placing impermeable caps over all
soil contamination left in place that poses a leachability
risk to groundwater, based on standards developed using
this guidance.

2

-------
Table D-2

Location-Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Floodplain Management
and Protection of
Wetlands

44 C.F.R. 9

Relevant
and
Appropriate

Federal Emergency Management Agency (FEMA) regulations
that set forth the policy, procedure and responsibilities to
implement and enforce Executive Order 11988 (Floodplain
Management) and Executive Order 11990 (Protection of
Wetlands). Prohibits activities that adversely affect a federally-
regulated wetland unless there is no practicable alternative and
the proposed action includes all practicable measures to
minimize harm to wetlands that may result from such use.
Requires the avoidance of impacts associated with the
occupancy and modification of federally-designated 100-year
and 500-year floodplain and to avoid development within
floodplain wherever there is a practicable alternative. An
assessment of impacts to 500-year floodplain is required for
critical actions - which includes siting waste facilities in a
floodplain. Requires public notice when proposing any action
in or affecting floodplain or wetlands.

If there is no practicable alternative method to work
in federal jurisdictional wetlands, then all practicable
measures will be taken to minimize and mitigate any
adverse impacts. Erosion and sedimentation control
measures will be adopted during excavation, soil
management, and capping activities to protect
federal jurisdictional wetlands. Standards for
excavating/ managing contaminated soil and cap
installation/O&M within the regulated 500-year
floodplain will be attained. There will be no significant
net loss of flood storage capacity and no significant
net increase in flood stage or velocities. Floodplain
habitat will be restored, to the extent practicable.
Public comment was solicited as part of the
Proposed Plan concerning the proposed alteration to
wetlands and floodplain and no negative comments
were received.

Resource Conservation
and Recovery Act
(RCRA) Floodplain
Restrictions for
Hazardous Waste
Facilities

42 U.S.C.
§§ 6901 et
seq

40 C.F.R. §
264.18(b)

Applicable

A hazardous waste treatment, storage, or disposal facility
located in a 100-year floodplain must be designed,
constructed, operated, and maintained to prevent washout or
to result in no adverse effects on human health or the
environment if washout were to occur.

Any hazardous waste generated from the
excavation, excavation dewatering or capping
activities or capped on-site will be managed so that it
will not impact floodplain resources.

RCRA Floodplain
Restrictions for Solid
Waste Disposal Facilities
and Practices

40 C.F.R. §
257.3-1

Applicable

Solid waste practices must not restrict the flow of a 100-year
flood, reduce the temporary water storage capacity of the
floodplain or result in washout of solid waste, so as to pose a
hazard to human life, wildlife, or land or water resources.

Any solid waste generated from excavation,
excavation dewatering, or capping activities or
capped on-site will be managed so that it will not
impact floodplain resources.

1

-------
Table D-2

Location-Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Clean Water Act §404,
and regulations

33 U.S.C.
1344, 40
C.F.R. Parts
230, 231
and 33
C.F.R. Parts
320-323

Applicable

For discharge of dredged or fill material into water bodies or
wetlands, there must be no practical alternative with less
adverse impact on aquatic ecosystem; discharge cannot cause
or contribute to violation of state water quality standard or toxic
effluent standard or jeopardize threatened or endangered
(T&E) species; discharge cannot significantly degrade waters
of U.S.; must take practicable steps to minimize and mitigate
adverse impacts; must evaluate impacts on flood level, flood
velocity, and flood storage capacity. Sets standards for
restoration and mitigation required as a result of unavoidable
impacts to aquatic resources. EPA must determine which
alternative is the "Least Environmentally Damaging Practicable
Alternative" (LEDPA) to protect wetland and aquatic resources.

Under this alternative excavation/management of
contaminated soil and capping activities may
possibly impact federal jurisdictional wetlands.
Activities effecting wetlands will be conducted in
accordance with these requirements including, but
not limited to, mitigation and/or restoration. EPA has
determined these alternatives are the LEDPA
because (a) there is no practical alternative method
that will achieve cleanup objectives with less adverse
impact and (b) all practical measures would be taken
to minimize and mitigate any adverse impacts from
the work. Public comment was solicited on EPA's
LEDPA finding in the Proposed Plan and no negative
comments were received.

Fish and Wildlife
Coordination Act

16 U.S.C.
§§ 662, 663

Applicable

Requires consultation with appropriate agencies to protect fish
and wildlife when federal actions may alter waterways. Must
develop measures to prevent and mitigate potential loss to the
maximum extent possible.

Consultation with appropriate federal agencies will
be maintained during planning and implementation of
these remedial alternatives that may alter protected
resource areas.

U.S. Army Corps of
Engineers, New England
District Compensatory
Mitigation Guidance (09-
07-2016)



To Be
Considered

This Guidance is to be considered when compensatory
mitigation to address impacts to federal jurisdictional wetlands
is appropriate for a particular remedial activity.

Under this alternative excavation/management of
contaminated soil and capping activities may
possibly impact federal jurisdictional wetlands.
Activities effecting federal jurisdictional wetlands will
be conducted in accordance with these guidance
standards for mitigation and/or restoration.

2

-------
Table D-2

Location-Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

State Standards









Massachusetts Wetlands
Protection Act and
Regulations

MGLc. 131
§40, 310
C.M.R.
10.00

Applicable

Regulations restrict dredging, filling, altering, or polluting inland
wetland resource areas and impose performance standards for
work in such areas (including 10.05(6)(k) (stormwater
management). Protected resource areas include: 10.54
(Bank); 10.55 (Bordering Vegetated Wetlands); 10.56 (Land
underWater); 10.57 (Bordering Land subject to Flooding); and
10.58 (Riverfront Area).

Under these alternatives soil excavation,
management, and capping may possibly impact
state regulated wetland resource areas and buffer
zones. Any remedial action conducted within 100
feet of a state regulated wetland and 200 feet from a
perennial stream will comply with these regulations.
Mitigation of impacts on State wetland resource
areas will be addressed.

Massachusetts
Hazardous Waste
Regulations, Location
Standards for Land
Subject to Flooding

310 C.M.R.
30.701

Applicable

Any new or expanding hazardous waste storage or treatment
facility (which only receives hazardous waste from on-site
sources), the active portion of which is located within the
boundary of land subject to flooding from the statistical 100-
year frequency storm, shall be flood-proofed. Flood-proofing
shall be designed, constructed, operated and maintained to
prevent floodwaters from coming into contact with hazardous
waste.

Any hazardous waste generated from the
excavation, excavation dewatering, or capping
activities or capped will be managed so that it will not
impact floodplain resources.

Massachusetts Clean
Water Act; Water Quality
Certification for Discharge
of Dredged or Fill Material

M.G.L.
ch.21, §§
26-53; 314
C.M.R.
§9.00

Applicable

Regulates discharges of dredged or fill material to protect
aquatic ecosystems.

Under this alternative dredging/filling of wetlands
during wetland soil/sediment excavation/
management and construction/O&M of the cap of the
cap will be conducted so as to not impair surface
water quality.

3

-------
Table D-3

Action Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Off-site Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Resource Conservation and
Recovery Act (RCRA) Subtitle
C; Hazardous Waste
Identification and Listing
Regulations; Generator and
Handler Requirements,
Closure and Post-Closure

42 U.S.C.
§6901 efseq.;
40 C.F.R. Parts
260-262 and
264

Applicable

Federal standards used to identify, manage, and
dispose of hazardous waste. Massachusetts has
been delegated the authority to administer these
RCRA standards through its state hazardous waste
management regulations. These provisions have
been adopted by the State. Federal financial
assurance requirements are defined at 40 C.F.R.
264.143.

Any wastes generated by soil excavation, excavation
dewatering, capping, and monitoring activity will be
analyzed under these standards to determine whether
they are listed or characteristic hazardous waste.
Excavation and capping of hazardous wastes will
need to meet closure/post closure standards,
including financial assurance requirements.

Toxic Substances Control Act
(TSCA); Polychlorinated
Biphenyl (PCB) Remediation
Waste

15 U.S.C. 2601
et seq.; 40
C.F.R.
761.61(c)

Applicable

This section of the TSCA regulations provides risk-
based cleanup and disposal options for PCB
remediation waste based on the risks posed by the
concentrations at which the PCBs are found.
Written approval for the proposed risk-based
cleanup must be obtained from the Director, Office
of Site Remediation and Restoration, USEPA
Region 1.

The Record of Decision contains a finding by EPA
(Appendix E) that the partial excavation, cap,
monitoring and institutional controls (ICs) will prevent
an unreasonable risk to human health or the
environment as long as required protective conditions
in the determination are met. All PCB contaminated
soil exceeding recreational human health risk
standards or ecological risk standards will be either
excavated and disposed of off-site at a licensed
facility or capped with a protective cover meeting risk-
based standards. Any remaining PCB soil
contamination exceeding residential risk standards
will be subject to ICs that will prevent residential
development. Monitoring and ICs will ensure long-
term protectiveness of the cap and enforcement of
restrictions on residential development. Any water
generated from the remedial action that exceeds EPA
risk standards will be treated to meet protective PCB
discharge limits. Remedial measures will be based on
in-situ PCB concentrations in soil.

Clean Water Act; National
Pollutant Discharge
Elimination System (NPDES)

40 C.F.R. Parts
122 and 125

Applicable

Establishes the specifications for discharging
pollutants from any point source into the waters of
the U.S. Also, includes stormwater standards for
activities disturbing more than one acre.

Any discharges from soil excavation/management,
dewatering of excavations, or construction and
operation and maintenance (O&M) of the caps will be
treated to meet these standards before discharge to
surface waters. Stormwater standards will be met if
there is over one acre of construction.

1

-------
Table D-3

Action Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Off-site Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Clean Water Act; Toxic
Pollutant Effluent Standards

40 CFR 129

Applicable

Regulates surface water discharges of specific toxic
pollutants, specifically certain pesticides and PCBs.

Any discharges from soil excavation/management,
dewatering of excavations, or construction and O&M
of the caps will be treated to meet applicable toxic
pollutant discharge standards (if regulated
contaminants are present) if the water is to be
discharged to surface waters.

Clean Water Act; General
Pretreatment Regulations for
Existing and New Sources of
Pollution

33 U.S.C. §
1251 et seq.;
40 C.F.R. §
403

Applicable

Standards for discharge into a Publicly Owned
Treatment Works (POTW).

Any water generated during soil excavation/
management, excavation dewatering, or construction
and O&M of the caps will be treated to meet
pretreatments standards if the water is to be
discharged to a POTW.

Clean Water Act, National
Recommended Water Quality
Criteria (NRWQC)

33 U.S.C. §
1314, 40 CFR
Part 131

Relevant and
Appropriate

NRWQC are provided by EPA for chemicals for
both the protection of human health and the
protection of aquatic life.

Used to establish monitoring standards for surface
waters and sediments, if required, for the remedial
action.

Clean Air Act (CAA),
Hazardous Air Pollutants;
National Emission Standards
for Hazardous Air Pollutants
(NESHAPS)

42.U.S.C. §
112(b)(1); 40
C.F.R. Part 61

Applicable

The regulations establish emissions standards for
189 hazardous air pollutants, including asbestos
(Subpart M). Standards set for dust, asbestos
abatement, and other release sources.

Remedial activities, including excavation/
management of soil, water treatment, and
construction and O&M of the caps, will be
implemented in accordance with these rules. No air
emissions from remedial activities will cause air
quality standards to be exceeded. If any building
demolition is required in buildings containing
asbestos, asbestos abatement standards will be met.
Dust standards will be complied with during
excavation and management of materials within the
OU.

Safe Drinking Water Act;
National Primary Drinking
Water Regulations, Maximum
Contaminant Levels (MCLs)

42 U.S.C. §
300f et seq. ] 40
C.F.R. 141,
Subparts B and
G

Relevant and
Appropriate

Federal drinking waters standards used as
groundwater monitoring standards when
contaminated media left in place.

Groundwater monitoring standards used to assess the
protectiveness of the caps.

2

-------
Table D-3

Action Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Off-site Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Safe Drinking Water Act;
National Primary Drinking
Water Regulations, Maximum
Contaminant Level Goals
(MCLGs)

42 U.S.C. §
300f et seq.; 40
C.F.R. 141,
Subpart F

Relevant and
Appropriate
for non zero
MCLGs only;
MCLGs set as
zero are To
Be

Considered.

Federal drinking waters standards used as
groundwater monitoring standards when
contaminated media left in place.

Groundwater monitoring standards used to assess the
protectiveness of the caps.

EPA Health Advisories



To Be
Considered

Federal risk-based standards for groundwater used
as groundwater monitoring standards when
contaminated media left in place.

Risk-based standards developed using these
advisories used to assess the protectiveness of the
caps.

RCRA, Interim Status
Treatment, Storage, and
Disposal Facility Standards,
Chemical, Physical and
Biological Treatment

40 C.F.R. Part
265, Subpart Q

Relevant and
Appropriate

Standards for operating chemical, physical and
biological treatment systems, including the proper
handling of reagents, system maintenance, and
closure procedures.

In situ treatment using amendments mixed into the
subsurface soils will be implemented in compliance
with these standards.

Generation of investigation
derived waste.

USEPA
OSWER
Publication
9345.3-03 FS
(January 1992)

To Be
Considered

Guidance on the management of Investigation-
Derived Waste (IDW) in a manner that ensures
protection of human health and the environment.

IDW generated as part of these remedial alternatives
will be managed based on guidance standards.

OSWER Technical Guide for
Assessing and Mitigating the
Vapor Intrusion Pathway from
Subsurface Vapor Sources to
Indoor Air.

OSWER
Publication
9200.2-154
(June 2015)

To Be
Considered

EPA guidance for addressing vapor intrusion issues
at CERCLA sites.

As part of mitigating for existing vapor intrusion
pathways in soil, contaminated soil that is a vapor
source will be excavated and disposed of off-site or
capped, if practicable. Vapor mitigation ICs will
address any remaining contaminated soil left on-site
that is a vapor source.

State Standards









Massachusetts Hazardous
Waste Rules for Identification
and Listing of Hazardous
Wastes

310 C.M.R.
30.100

Applicable

Massachusetts is delegated to administer RCRA
through its State regulations. These regulations
establish requirements for determining whether
wastes are either listed or characteristic hazardous
waste.

Any wastes generated by soil excavation, excavation
dewatering, capping and monitoring activity will be
analyzed under these standards to determine whether
they are listed or characteristic hazardous waste.

3

-------
Table D-3

Action Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Off-site Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Hazardous
Waste Management Rules -
Requirements for Generators

310 C.M.R.
30.300

Applicable

These regulations contain requirements for
generators of hazardous waste. The regulations
apply to generators of sampling waste and also
apply to the accumulation of waste prior to off-site
disposal.

Any wastes generated by soil excavation, excavation
dewatering, capping and monitoring activity will be
managed in accordance with the substantive
requirements of these regulations.

Massachusetts Hazardous
Waste Management Rules -
General standards for
hazardous waste facilities

310 C.M.R.
30.500

Applicable

General facility requirements for waste analysis,
security measures, inspections, and training
requirements. Section 30.580 addresses closure
and Section 30.590 post-closure of hazardous
waste facilities.

If hazardous waste is managed prior to off-site
disposal or capped in place these facility standards
will be met.

Massachusetts Hazardous
Waste Rules - Special
requirements for wastewater
treatment units

310 C.M.R.
30.605

Relevant and
Appropriate

Standards for wastewater treatment units for the
treatment of hazardous waste if water is to be
discharged to a Publicly Owned Treatment Works
(POTW).

Any water generated by soil excavation, excavation
dewatering, capping and monitoring activity that
meets hazardous waste standards will be treated to
meet pretreatment standards, if the water is to be
discharged to a POTW.

Massachusetts Hazardous
Waste Rules - Landfill
Closure/Post Closure

310 C.M.R.
30.633

Relevant and
Appropriate

Standards for capping landfills that are relevant and
appropriate for capping hazardous waste left in
place: (1) Provide long-term minimization of
migration of liquids through the waste; (2) Function
with minimum maintenance; (3) Promote drainage
and minimize erosion or abrasion of the cover; (4)
Accommodate settling and subsidence so that the
cover's integrity is maintained; and (5) meet
relevant and appropriate post-closure requirements
in 310 C.M.R. 590.

If hazardous waste is capped in place these
performance standards for protective caps will be met.

Massachusetts Hazardous
Waste Rules, Groundwater
protection

310 C.M.R.
30.660

Relevant and
Appropriate

Hazardous waste facility standards for the
protection of groundwater.

If hazardous waste is managed prior to off-site
disposal or capped in place the remedial action must
prevent migration of contaminants into groundwater.
In situ treatment using amendments mixed into the
subsurface soils will be implemented in compliance
with these groundwater protection standards.

4

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Table D-3

Action Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Off-site Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Hazardous
Waste Rules - Containers

310 C.M.R.
30.680

Applicable

Establishes requirements for the management of
containers, such as drums, that would hold field-
generated hazardous wastes.

If any remedial activity generates hazardous wastes
that will be stored in containers, the containers will be
managed in accordance with the substantive
requirements of these regulations.

Massachusetts Hazardous
Waste Rules - Management,
Storage, and Treatment in
Tanks

310 C.M.R.
30.690

Applicable

These standards specify requirements for tank
systems used to store or treat hazardous waste.
Provides specifications for design and installation of
tank systems. Requires secondary containment,
leak detection systems, and inspections. Identifies
general operating requirements, and closure and
post-closure care.

If any remedial activity generates hazardous wastes
that will be stored in tanks, the tanks will be managed
in accordance with the substantive requirements of
these regulations.

Massachusetts Clean Water
Act; Surface Water Discharge
Permit Regulations

M.G.L. ch 21,
§§ 26-53; 314
C.M.R. 3.00

Applicable

These regulations provide that discharges to waters
of the Commonwealth shall not result in
exceedances of MA Surface Water Quality
Standards (MSWQS).

Any water generated by soil excavation, soil
dewatering, capping and monitoring activity will be
treated to meet discharge standards if the water is to
be discharged to surface waters.

Massachusetts Clean Water
Act; MA Surface Water
Quality Standards (MSWQS)

M.G.L. ch 21,
§§ 26-53; 314
C.M.R. 4.00

Relevant and
Appropriate

These standards designate the most sensitive uses
for which the various waters of the Commonwealth
shall be enhanced, maintained, or protected.
Minimum water quality criteria required to sustain
the designated uses are established.

Used to establish monitoring standards for surface
waters and sediments, if required, for the remedial
action.

Massachusetts Supplemental
Requirements for Hazardous
Waste Management Facilities

314 C.M.R.
8.03

Relevant and
Appropriate

This regulation outlines the additional requirements
that must be satisfied in order for a RCRA facility to
comply with the NPDES regulation.

Any water generated by soil excavation, soil
dewatering, capping and monitoring activity that
meets hazardous waste standards will be treated to
meet NPDES standards if the water is to be
discharged to surface waters.

Operation and Maintenance
and Pretreatment Standards
for Wastewater Treatment
Works and Indirect
Dischargers

314 C.M.R.
12.03(6-7),(9);
12.04(3),(6-
14); 12.05(1 ),(6)
.(12-13);
12.06(1-3)

Applicable

Standards for the operation of waste water
treatment works.

The water treatment system will be operated and
maintained in compliance with these standards.

Prohibitions and Standards for
Discharges to POTWs

314 C.M.R.
12.08

Applicable

Standards for discharge into a Publicly Owned
Treatment Works (POTW).

Any water generated by soil excavation, soil
dewatering, capping and monitoring activity will be
treated to meet pretreatments standards, if the water
is to be discharged to a POTW.

5

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Table D-3

Action Specific ARARs and TBCs for Soil at the Whitney Barrel, Murphy Waste Oil, and Aberjona Auto Parts Areas
Alternatives SW3, SM3, and SA3: Soil Excavation & Off-site Disposal, Capping, and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Solid Waste
Rules Groundwater
Monitoring

310 C.M.R.
118

Relevant and
Appropriate

Solid waste facility standards for monitoring
groundwater.

Monitoring of the caps will ensure that groundwater is
not impaired by the capped contamination.

Massachusetts Ambient Air
Quality Standards

310 C.M.R.
6.00

Applicable

Sets primary and secondary standards for
emissions of certain contaminants, including
particulate matter.

Emission standards, including for dust, will be
achieved during soil excavation/management, water
treatment, and construction/O&M of the caps.

Massachusetts Air Pollution
Control Regulations

310 C.M.R.
7.00

Applicable

These regulations set emission limits necessary to
attain ambient air quality standards, including for
asbestos (7.15).

Emission standards, including for dust, will be
achieved during soil excavation/management, water
treatment, and construction/O&M of the caps. If any
building demolition is required in buildings containing
asbestos, asbestos abatement standards will be met.

Massachusetts Contingency
Plan, Implementation of
Activity and Use Limitations

310 C.M.R.
40.1070(4)

Relevant and
Appropriate

Establish standards for ICs at CERCLA sites in
Massachusetts.

Institutional controls will be established consistent
with State standards for enforceable restrictions on
contaminated property.

Massachusetts Water Quality
Standards Implementation
Policy for the Control of Toxic
Pollutants in Surface Waters

Feb. 1999

To Be
Considered

Guidance on controlling toxic pollutant discharges
to surface waters

This guidance will be used in the establishment of
monitoring standards for surface waters and
sediments, if required for the remedial action.

Allowable Sound

Air Quality
Control Policy
#90-001

To Be
Considered

Guidance on sound emissions.

To be used to assess whether any remedial measures
exceed State noise guidance levels.

Massachusetts Standard
References for Monitoring
Wells

WSC-310-91

To Be
Considered

Guidance on locating, drilling, installing, sampling
and decommissioning monitoring wells.

Monitoring wells will be installed, maintained and
decommissioned based on guidance standards.

Erosion and Sediment Control
Guidance



To Be
Considered

Guidance on preventing erosion and sedimentation.

Remedial actions will be managed to control erosion
and sedimentation.

6

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Table D-4

Chemical-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Safe Drinking Water Act;
National primary drinking
water regulations,
Maximum Contaminant
Levels

42 U.S.C. §
300f et
seq. \ 40
C.F.R. 141,
Subparts B
and G

Relevant
and
Appropriate

Establishes Maximum Contaminant Levels
(MCLs) for common organic and inorganic
contaminants applicable to public drinking
water supplies. Used as relevant and
appropriate standards for aquifers and
surface water bodies that are potential
drinking water sources.

This alternative would prevent exposure to NAPL in
groundwater that exceeds these standards through:
excavation and off-site disposal of NAPL and NAPL-
contaminated media, to the extent practicable; treatment
of water generated from dewatering excavations and
excavated material; and monitoring/ICs to prevent
exposure to any remnant NAPL until it no longer exceeds
regulatory standards due to natural attenuation and
concurrent remedial measures for soil and groundwater.

Safe Drinking Water Act;
National primary drinking
water regulations,
Maximum Contaminant
Level Goals

42 U.S.C. §
300f et
seq. \ 40
C.F.R. 141,
Subpart F

Relevant
and
Appropriate
for non

zero
MCLGs
only;
MCLGs set

as zero
are To Be
Considered

Establishes maximum contaminant level
goals (MCLGs) for public water supplies.
MCLGs are health goals for drinking water
sources. These unenforceable health goals
are available for a number of organic and
inorganic compounds.

This alternative would prevent exposure to NAPL in
groundwater that exceeds these standards through:
excavation and off-site disposal of NAPL and NAPL-
contaminated media, to the extent practicable; treatment
of water generated from dewatering excavations and
excavated material; and monitoring/ICs to prevent
exposure to any remnant NAPL until it no longer exceeds
regulatory standards due to natural attenuation and
concurrent remedial measures for soil and groundwater.

EPA Health Advisories



To Be
Considered

EPA publishes contaminant-specific health
advisories that indicate the non-
carcinogenic risks associated with
consuming contaminated drinking water.
Used to develop risk-based cleanup
standards.

This alternative would prevent exposure to NAPL
contaminants in groundwater and soil which contribute to
a calculated non-carcinogenic risk, developed using this
guidance through: skimming and off-site disposal of NAPL
to the extent practicable; treatment of water generated
from dewatering excavations and excavated material;,
and monitoring/ICs to prevent exposure to any remnant
NAPL until it no longer poses a risk due to natural
attenuation and concurrent remedial measures for soil
and groundwater.

1

-------
Table D-4

Chemical-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Guidelines for
Carcinogenic Risk
Assessment

EPA/630/P-
03/001F

To Be
Considered

These guidelines provide guidance on
conducting risk assessments involving
carcinogens.

This alternative would prevent exposure to NAPL
contaminants which contribute to a calculated
carcinogenic risk, developed using this guidance, through:
1) excavation of NAPL and off-site disposal, to the extent
practicable, to address commercial/industrial exposure; 2)
monitoring to assess when exposure to any remnant
NAPL no longer poses a commercial/industrial risk; and 3)
ICs to prevent residential development. Additional NAPL
is expected to be removed during concurrent remedial
measures for soil and groundwater.

Supplemental Guidance
for Assessing
Susceptibility from Early-
Life Exposure to
Carcinogens

EPA/630/R-
03/003F

To Be
Considered

This provides guidance on assessing risk to
children from carcinogens.

This alternative would prevent exposure to NAPL
contaminants which contribute to a calculated
carcinogenic risk to children, developed using this
guidance through: 1) excavation of NAPL and off-site
disposal, to the extent practicable, to address
commercial/industrial exposure; 2) monitoring to assess
when exposure to any remnant NAPL no longer poses a
commercial/industrial risk; and 3) ICs to prevent
residential development. Additional NAPL is expected to
be removed during concurrent remedial measures for soil
and groundwater.

EPA Risk Reference
Doses (RfDs)



To Be
Considered

Guidance used to compute human health
hazard resulting from exposure to non-
carcinogens in site media. RfDs are
considered to be the levels unlikely to cause
significant adverse health effects associated
with a threshold mechanism of action in
human exposure for a lifetime.

This alternative would prevent exposure to NAPL
contaminants which contribute to a calculated non-
carcinogenic risk, developed using this guidance through:
1) excavation of NAPL and off-site disposal, to the extent
practicable, to address commercial/industrial exposure; 2)
monitoring to assess when exposure to any remnant
NAPL no longer poses a commercial/industrial risk; and 3)
ICs to prevent residential development. Additional NAPL
is expected to be removed during concurrent remedial
measures for soil and groundwater.

2

-------
Table D-4

Chemical-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Human Health
Assessment Cancer
Slope Factors (CSFs)



To Be
Considered

CSFs are estimates of the upper-bound
probability of an individual developing
cancer as a result of a lifetime exposure to a
particular concentration of a potential
carcinogen.

This alternative would prevent exposure to NAPL
contaminants which contribute to a calculated
carcinogenic risk, developed using this guidance through:
1) excavation of NAPL and off-site disposal, to the extent
practicable, to address commercial/industrial exposure; 2)
monitoring to assess when exposure to any remnant
NAPL no longer poses a commercial/industrial risk; and 3)
ICs to prevent residential development. Additional NAPL
is expected to be removed during concurrent remedial
measures for soil and groundwater.

EPA Carcinogenic
Assessment Group
Potency Factors



To Be
Considered

These factors are used to evaluate an
acceptable risk from a carcinogen.

This alternative would prevent exposure to NAPL
contaminants which contribute to a calculated
carcinogenic risk, developed using this guidance through:
1) excavation of NAPL and off-site disposal, to the extent
practicable, to address commercial/industrial exposure; 2)
monitoring to assess when exposure to any remnant
NAPL no longer poses a commercial/industrial risk; and 3)
ICs to prevent residential development. Additional NAPL
is expected to be removed during concurrent remedial
measures for soil and groundwater.

Updated Scientific
Considerations for Lead
in Soil Cleanups

EPA OLEM

Directive

9200.2-167

To Be
Considered

EPA Guidance for evaluating risks posed by
lead in soil. Used to develop site-specific
risk-based standards. Recommends
evaluating potential risks from exposures to
lead at a Superfund site at a target blood
lead level lower than 10 [jg/dL..

This alternative would prevent exposure to lead in NAPL
which contributes to a calculated risk, developed using
this guidance through: 1) excavation and off-site disposal
of lead-contaminated NAPL, to the extent practicable, to
address commercial/industrial exposure; 2) monitoring to
assess when exposure to any remnant lead-contaminated
NAPL no longer poses a commercial/ industrial risk; and
3) ICs to prevent residential development. Additional
lead-contaminated NAPL is expected to be removed
during concurrent remedial measures for soil and
groundwater.

3

-------
Table D-4

Chemical-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Recommendations of
the Technical Review
Workgroup for Lead for
an approach to
Assessing Risks
Associated with Adult
Exposure to Lead In Soil

EPA-540-
R-03-001
(January
2003)

To Be
Considered

EPA Guidance for evaluating risks posed by
lead in soil.

This alternative would prevent exposure to lead in NAPL
which contributes to a calculated risk, developed using
this guidance through: 1) excavation and off-site disposal
of lead-contaminated NAPL, to the extent practicable, to
address commercial/industrial exposure; 2) monitoring to
assess when exposure to any remnant lead-contaminated
NAPL no longer poses a commercial/ industrial risk; and
3) ICs to prevent residential development. Additional
lead-contaminated NAPL is expected to be removed
during concurrent remedial measures for soil and
groundwater.

Guidance on Remedial
Actions for Superfund
Sites with PCB
Contamination

EPA-540-
G-90-007
(August
1990)

To Be
Considered

EPA Guidance for evaluating risks posed by
PCBs at Superfund sites. Used to develop
risk-based cleanup standards.

This alternative would prevent exposure to PCBs in -
NAPL which contributes to a calculated risk, developed
using this guidance through: 1) excavation of PCB-
contaminated NAPL and off-site disposal, to the extent
practicable, to address commercial/industrial exposure; 2)
monitoring to assess when exposure to any remnant
NAPL no longer poses a commercial/industrial risk; and 3)
ICs to prevent residential development. Additional PCB-
contaminated NAPL is expected to be removed during
concurrent remedial measures for soil and groundwater.

State Standards









Massachusetts Drinking
Water Regulations

310 C.M.R.
22.00

Relevant
and
Appropriate

Establishes maximum contaminant levels
that apply to public drinking water supplies.
MA Maximum Contaminant Levels and
Maximum Contaminant Level Goals are
specified for numerous contaminants,
including inorganic and organic chemicals.
For the most part, the numerical criteria are
identical to Federal SDWA MCLs and
MCLGs, although there are several
additional chemicals that have criteria.

This alternative would prevent exposure to NAPL in
groundwater that exceeds these State standards through:
excavation and off-site disposal of NAPL and NAPL-
contaminated media, to the extent practicable; treatment
of water generated from dewatering excavations and
excavated material; and monitoring/ICs to prevent
exposure to any remnant NAPL until it no longer exceeds
regulatory standards due to natural attenuation and
concurrent remedial measures for soil and groundwater.

4

-------
Table D-5

Location-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain
Requirement

Federal Standards









Floodplain
Management and
Protection of
Wetlands

44 C.F.R.
9

Relevant
and
Appropriate

FEMA regulations that set forth the policy,
procedure and responsibilities to implement
and enforce Executive Order 11988
(Floodplain Management) and Executive
Order 11990 (Protection of Wetlands).
Prohibits activities that adversely affect a
federally-regulated wetland unless there is
no practicable alternative and the proposed
action includes all practicable measures to
minimize harm to wetlands that may result
from such use. Requires the avoidance of
impacts associated with the occupancy and
modification of federally-designated 100-
year and 500-year floodplain and to avoid
development within floodplain wherever
there is a practicable alternative. An
assessment of impacts to 500-year
floodplain is required for critical actions -
which includes siting waste facilities in a
floodplain. Requires public notice when
proposing any action in or affecting
floodplain or wetlands.

If there is no practicable alternative method
to work in federal jurisdictional wetlands,
then all practicable measures will be taken
to minimize and mitigate any adverse
impacts. Erosion and sedimentation
control measures will be adopted during
excavation, material management, and
restoration activities to protect federal
jurisdictional wetlands. Standards for
excavating and managing contaminated
NAPL/soil within the regulated 500-year
floodplain will be attained. After completion
of the work, there will be no significant net
loss of flood storage capacity and no
significant net increase in flood stage or
velocities. Floodplain habitat will be
restored, to the extent practicable. Public
comment was solicited as part of the
Proposed Plan concerning the proposed
alteration to wetlands and floodplain and no
negative comments were received.

Resource
Conservation and
Recovery Act
(RCRA) Floodplain
Restrictions for
Hazardous Waste
Facilities

42 U.S.C.
§§ 6901 et
seq

40 C.F.R.

§

264.18(b)

Applicable

A hazardous waste treatment, storage, or
disposal facility located in a 100-year
floodplain must be designed, constructed,
operated, and maintained to prevent
washout or to result in no adverse effects
on human health or the environment if
washout were to occur.

To the extent any hazardous waste is
generated from the excavation activities the
material will be managed so that it will not
impact floodplain resources.

1

-------
Table D-5

Location-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain
Requirement

RCRA Floodplain
Restrictions for Solid
Waste Disposal
Facilities and
Practices

40 C.F.R.
§257.3-1

Applicable

Solid waste practices must not restrict the
flow of a 100-year flood, reduce the
temporary water storage capacity of the
floodplain or result in washout of solid
waste, so as to pose a hazard to human
life, wildlife, or land or water resources.

Any solid waste generated from the
excavation activities will be managed so
that it will not impact floodplain resources.

Clean Water Act
§404, and
regulations

33 U.S.C.
1344, 40
C.F.R.
Parts 230,
231 and 33
C.F.R.
Parts 320-
323

Applicable

For discharge of dredged or fill material into
water bodies or wetlands, there must be no
practical alternative with less adverse
impact on aquatic ecosystem; discharge
cannot cause or contribute to violation of
state water quality standard or toxic effluent
standard or jeopardize threatened or
endangered (T&E) species; discharge
cannot significantly degrade waters of U.S.;
must take practicable steps to minimize and
mitigate adverse impacts; must evaluate
impacts on flood level, flood velocity, and
flood storage capacity. Sets standards for
restoration and mitigation required as a
result of unavoidable impacts to aquatic
resources. EPA must determine which
alternative is the "Least Environmentally
Damaging Practicable Alternative" (LEDPA)
to protect wetland and aquatic resources.

Under this alternative excavation of
contaminated NAPL/soil may possibly
impact federal jurisdictional wetlands.
Activities effecting wetlands will be
conducted in accordance with these
requirements including, but not limited to,
mitigation and/or restoration. EPA has
determined this alternative is the LEDPA
because (a) there is no practical alternative
method that will achieve cleanup objectives
with less adverse impact and (b) all
practical measures would be taken to
minimize and mitigate any adverse impacts
from the work. Public comment was
solicited on EPA's LEDPA finding in the
Proposed Plan and no negative comments
were received.

Fish and Wildlife
Coordination Act

16 U.S.C.
§§ 662,
663

Applicable

Requires consultation with appropriate
agencies to protect fish and wildlife when
federal actions may alter waterways. Must
develop measures to prevent and mitigate
potential loss to the maximum extent
possible.

Consultation with appropriate federal
agencies will be maintained during planning
and implementation of the remedial
alternative that may alter protected
resource areas

2

-------
Table D-5

Location-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain
Requirement

National Historical
Preservation Act,

16 U.S.C.
469 et
seq36
C.F.R. Part
65

Applicable

When a federal agency finds, or is notified,
that its activities in connection with a federal
construction project may cause irreparable
loss or destruction of significant scientific,
pre-historical, historical, or archeological
data, the substantive standards under the
Act will be met.

Any undisturbed areas altered by the
NAPL/soil excavation activities will be
assessed to ensure no protected resource
areas are present. If present there will be
consultation with federal and state
preservation officials to address measures
to avoid, minimize and/or mitigate any
impacts to protected resource areas.

U.S. Army Corps of
Engineers, New
England District
Compensatory
Mitigation Guidance
(09-07-2016)



To Be
Considered

This Guidance is to be considered when
compensatory mitigation to address impacts
to federal jurisdictional wetlands is
appropriate for a particular remedial activity.

Under this alternative excavation of
contaminated NAPL/soil may possibly
impact federal jurisdictional wetlands.
Activities effecting federal jurisdictional
wetlands will be conducted in accordance
with these guidance standards for mitigation
and/or restoration.

State Standards









Massachusetts
Wetlands Protection
Act and Regulations

MGL c.
131 §40,
310
C.M.R.
10.00

Applicable

Regulations restrict dredging, filling,
altering, or polluting inland wetland
resource areas and impose performance
standards for work in such areas (including
10.05(6)(k) (stormwater management).
Protected resource areas include: 10.54
(Bank); 10.55 (Bordering Vegetated
Wetlands); 10.56 (Land underWater);
10.57 (Bordering Land subject to Flooding);
and 10.58 (Riverfront Area).

Under this alternative NAPL/soil excavation
and excavated material management may
possibly impact state regulated wetland
resource areas and buffer zones. Any
remedial action conducted within 100 feet of
a state regulated wetland resource area
and 200 feet from a perennial stream will
comply with these regulations. Mitigation of
impacts on State wetland resource areas
will be addressed.

3

-------
Table D-5

Location-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain
Requirement

Massachusetts
Clean Water Act;
Water Quality
Certification for
Discharge of
Dredged or Fill
Material

M.G.L.
ch.21, §§
26-53; 314
C.M.R.
§9.00

Applicable

Regulates discharges of dredged or fill
material to protect aquatic ecosystems.

Any required dredging/filling of wetlands
resulting from the excavation of NAPL and
NAPL-contaminated materials will be
conducted so as to not impair surface water
quality.

Massachusetts
Hazardous Waste
Regulations,
Location Standards
for Land Subject to
Flooding

310

C.M.R.

30.701

Applicable

Any new or expanding hazardous waste
storage or treatment facility (which only
receives hazardous waste from on-site
sources), the active portion of which is
located within the boundary of land subject
to flooding from the statistical 100-year
frequency storm, shall be floodproofed.
Floodproofing shall be designed,
constructed, operated and maintained to
prevent floodwaters from coming into
contact with hazardous waste.

To the extent any hazardous waste is
generated from the excavation activities the
material will be managed so that it will not
impact floodplain resources.

Antiquities Act and
Regulations

M.G.L. ch.
9, §§26-
27; 950
C.M.R.
71.00

Relevant
and
Appropriate

Projects which are state-funded or state-
licensed or which are on state property
must eliminate, limit, or mitigate adverse
effects to properties listed in the register of
historic places. Establishes coordination
with the National Historic Preservation Act.

Any undisturbed areas altered by the
NAPL/soil excavation activities will be
assessed to ensure no protected resource
areas are present. If present there will be
consultation with federal and state
preservation officials to address measures
to avoid, minimize and/or mitigate any
impacts to protected resource areas.

4

-------
Table D-6

Action-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Resource Conservation and
Recovery Act (RCRA) Subtitle C;
Hazardous Waste Identification
and Listing Regulations; Generator
and Handler Requirements,
Closure and Post-Closure

42 U.S.C.
§6901 et
seq. \ 40
C.F.R.
Parts 260-
262 and
264

Applicable

Federal standards used to identify,
manage, and dispose of hazardous waste.
Massachusetts has been delegated the
authority to administer these RCRA
standards through its state hazardous
waste management regulations. These
provisions have been adopted by the State.
Federal financial assurance requirements
are defined at 40 C.F.R. 264.143.

Any wastes generated by remedial activity will
be analyzed under these standards to
determine whether they are listed or
characteristic hazardous waste. Non-
hazardous materials will be disposed
appropriately. All NAPL meeting either listed
or characteristic hazardous waste standards
will be excavated and disposed of off-site at a
licensed facility. Releases from regulated
hazardous waste facilities will be addressed
under applicable closure/post closure
standards, including financial assurance
requirements.

Toxic Substances Control Act
(TSCA); PCB Remediation Waste

15 U.S.C.
2601 et
seq40
C.F.R.
761.61(c)

Applicable

This section of the TSCA regulations
provides risk-based cleanup and disposal
options for PCB remediation waste based
on the risks posed by the concentrations at
which the PCBs are found. Written
approval for the proposed risk-based
cleanup must be obtained from the
Director, Office of Site Remediation and
Restoration, USEPA Region 1.

The Record of Decision contains a finding by
EPA (Appendix E) that excavation of all PCB-
contaminated NAPL that exceeds risk-based
PCB standards, to the extent practicable;
proper management of excavated material;
and monitoring/ICs to prevent exposure to any
remnant NAPL (until it no longer poses a risk
due to natural attenuation and concurrent
remedial measures for soil and groundwater)
will prevent an unreasonable risk to human
health or the environment as long as required
protective conditions in the determination are
met. Remedial measures will be based on in-
situ PCB concentrations in NAPL and NAPL-
contaminated media.

1

-------
Table D-6

Action-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Clean Water Act; National
Pollutant Discharge Elimination
System (NPDES)

40 C.F.R.
Parts 122
and 125

Applicable

Establishes the specifications for
discharging pollutants from any point
source into the waters of the U.S. Also,
includes stormwater standards for activities
disturbing more than one acre.

Any water generated during NAPL excavation
or dewatering activities (if required) will be
treated to meet NPDES standards if the water
is to be discharged to surface waters.
Stormwater standards will be met if over an
acre is altered by the remedial action.

Clean Water Act; Toxic Pollutant
Effluent Standards

40 CFR
129

Applicable

Regulates surface water discharges of
specific toxic pollutants, specifically certain
pesticides and PCBs.

Any water contaminated with the specific toxic
pollutants addressed by this regulation
generated during NAPL excavation or
dewatering activities (if required) will be treated
to meet applicable toxic pollutant discharge
standards if the water is to be discharged to
surface waters.

Clean Water Act; General
Pretreatment Regulations for
Existing and New Sources of
Pollution

33 U.S.C. §
1251 et
seq. \ 40
C.F.R. §
403

Applicable

Standards for discharge into a Publicly
Owned Treatment Works (POTW).

Any water generated during NAPL excavation
or dewatering activities (if required) will be
treated to meet pretreatments standards if the
water is to be discharged to a POTW.

Clean Water Act, National
Recommended Water Quality
Criteria

33 U.S.C. §
1314, 40
CFR Part
131

Relevant and
Appropriate

NRWQC are provided by EPA for
chemicals for both the protection of human
health and the protection of aquatic life.

Used to establish monitoring standards for
surface waters and sediments, if required for
the remedial action.

Clean Air Act (CAA), Hazardous
Air Pollutants; National Emission
Standards for Hazardous Air
Pollutants (NESHAPS)

42.U.S.C. §
112(b)(1);
40 C.F.R.
Part 61

Applicable

The regulations establish emissions
standards for 189 hazardous air pollutants,
including asbestos (Subpart M). Standards
set for dust, asbestos abatement, and other
release sources.

Remedial activities, including excavation of
NAPL and possible treatment of NAPL prior to
off-site disposal will be implemented in
accordance with these rules. No air emissions
from remedial activities will cause air quality
standards to be exceeded. If any building
demolition is required in buildings containing
asbestos, asbestos abatement standards will
be met. Dust standards will be complied with
during excavation and management of
materials within the OU.

2

-------
Table D-6

Action-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

RCRA, Air Emission Standards for
Process Vents

40 C.F.R.
Part 264,
Subpart AA

Applicable, if
VOC
emissions
over 10 ppm
or greater;
Relevant and
Appropriate,
if less than
10 ppm

RCRA emissions standards not delegated
to the State. Standards for process vents
for systems that treat RCRA wastes that
have total organic concentrations of 10
ppm or greater.

Possible treatment of NAPL prior to off-site
disposal will be implemented in accordance
with these air emission rules. No air emissions
from remedial activities will cause air quality
standards to be exceeded.

RCRA, Air Emission Standards for
Equipment Leaks

40 C.F.R.
Part 264,
Subpart BB

Applicable, if
VOC
emissions
over10 ppm
or greater;
Relevant and
Appropriate,
if less than
10 ppm

RCRA emissions standards not delegated
to the State. Standards for air equipment
leaks for systems that treat RCRA wastes
that have total organic concentrations of 10
ppm or greater.

Possible treatment of NAPL prior to off-site
disposal will be implemented in accordance
with these air emission rules. No air emissions
from remedial activities will cause air quality
standards to be exceeded.

Generation of investigation derived
waste.

USEPA

OSWER

Publication

9345.3-03

FS

(January
1992)

To Be
Considered

Guidance on the management of
Investigation-Derived Waste (IDW) in a
manner that ensures protection of human
health and the environment.

IDW generated as part of this remedial
alternative will be managed based on guidance
standards.

OSWER Technical Guide for
Assessing and Mitigating the
Vapor Intrusion Pathway from
Subsurface Vapor Sources to
Indoor Air.

OSWER

Publication

9200.2-154

(June

2015)

To Be
Considered

EPA guidance for addressing vapor
intrusion issues at CERCLA sites.

As part of mitigating for existing vapor intrusion
pathways, NAPL that is a vapor source will be
excavated and disposed of off-site, if
practicable. Vapor mitigation ICs will address
any remaining NAPL left on-site that is a vapor
source.

3

-------
Table D-6

Action-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

State Standards









Massachusetts Hazardous Waste
Rules for Identification and Listing
of Hazardous Wastes

310 C.M.R.
30.100

Applicable

Massachusetts is delegated to administer
RCRA through its State regulations. These
regulations establish requirements for
determining whether wastes are either
listed or characteristic hazardous waste.

Any wastes generated by remedial activity will
be analyzed under these standards to
determine whether they are listed or
characteristic hazardous waste.

Massachusetts Hazardous Waste
Management Rules -
Requirements for Generators

310 C.M.R.
30.300

Applicable

These regulations contain requirements for
generators of hazardous waste. The
regulations apply to generators of sampling
waste and also apply to the accumulation
of waste prior to off-site disposal

To the extent any remedial activity generates
hazardous wastes, the waste will be managed
in accordance with the substantive
requirements of these regulations.

Massachusetts Hazardous Waste
Management Rules - General
standards for hazardous waste
facilities

310 C.M.R.
30.500

Applicable

General facility requirements for waste
analysis, security measures, inspections,
and training requirements. Section 30.580
addresses closure and Section 30.590
post-closure of hazardous waste facilities.

If any remedial activity generates hazardous
wastes, on-site facilities used to handle the
waste will be managed in accordance with the
substantive requirements of these regulations.
Removal of all NAPL exceeding hazardous
waste standards will meet closure/post closure
requirements for releases from current or
formerly active hazardous waste facilities.

Massachusetts Hazardous Waste
Rules - Special requirements for
wastewater treatment units

310 C.M.R.
30.605

Relevant and
Appropriate

Standards for wastewater treatment units
for the treatment of hazardous waste.

Any water generated during NAPL excavation
or dewatering activities (if required) that meets
hazardous waste standards will be treated to
meet pretreatments standards, if the water is to
be discharged to a POTW.

Massachusetts Hazardous Waste
Rules, Groundwater protection

310 C.M.R.
30.660

Relevant and
Appropriate

Hazardous waste facility standards for the
protection of groundwater.

Excavation and off-site disposal of NAPL which
qualifies as hazardous waste will protect
groundwater quality. Any hazardous waste
generated by the remedial alternative will be
managed to prevent contaminant migration to
groundwater.

4

-------
Table D-6

Action-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Hazardous Waste
Rules - Containers

310 C.M.R.
30.680

Applicable

Establishes requirements for the
management of containers, such as drums,
that would hold field-generated hazardous
wastes.

If any remedial activity generates hazardous
wastes that will be stored in containers, the
containers will be managed in accordance with
the substantive requirements of these
regulations.

Massachusetts Hazardous Waste
Rules - Management, Storage, and
Treatment in Tanks

310 C.M.R.
30.690

Applicable

These standards specify requirements for
tank systems used to store or treat
hazardous waste. Provides specifications
for design and installation of tank systems.
Requires secondary containment, leak
detection systems, and inspections.
Identifies general operating requirements,
and closure and post-closure care.

If any remedial activity generates hazardous
wastes that will be stored in tanks, the tanks
will be managed in accordance with the
substantive requirements of these regulations.

Massachusetts Supplemental
Requirements for Hazardous
Waste Management Facilities

314 C.M.R.
8.03

Relevant and
Appropriate

This regulation outlines the additional
requirements that must be satisfied in order
for a RCRA facility to comply with the
NPDES regulation.

Any water generated during NAPL excavation
or dewatering activities (if required) that meets
hazardous waste standards will be treated to
meet NPDES standards if the water is to be
discharged to surface waters.

Massachusetts Clean Water Act;
Surface Water Discharge Permit
Regulations

M.G.L. ch
21, §§ 26-
53; 314
C.M.R.
3.00

Applicable

These regulations provide that discharges
to waters of the Commonwealth shall not
result in exceedances of MA Surface Water
Quality Standards (MSWQS).

Any water generated during NAPL excavation
or dewatering activities (if required) will be
treated to meet discharge standards if the
water is to be discharged to surface waters.

Prohibitions and Standards for
Discharges to POTWs

324 C.M.R.
12.08

Applicable

Standards for discharge into a Publicly
Owned Treatment Works (POTW).

Any water generated during NAPL excavation
or dewatering activities (if required) will be
treated to meet pretreatments standards if the
water is to be discharged to a POTW.

Massachusetts Clean Water Act;
MA Surface Water Quality
Standards (MSWQS)

M.G.L. ch
21, §§ 26-
53; 314
C.M.R.
4.00)

Relevant and
Appropriate

These standards designate the most
sensitive uses for which the various waters
of the Commonwealth shall be enhanced,
maintained, or protected. Minimum water
quality criteria required to sustain the
designated uses are established.

Used to establish monitoring standards for
surface waters and sediments, if required for
the remedial action.

5

-------
Table D-6

Action-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Ambient Air Quality
Standards

310 C.M.R.
6.00

Applicable

Sets primary and secondary standards for
emissions of certain contaminants,
including particulate matter.

Remedial activities, including excavation and
management of NAPL and any NAPL
treatment will be implemented in accordance
with these rules. No air emissions from
remedial activities will cause air quality
standards to be exceeded. Dust standards will
be complied with during excavation and
management of materials at the OU.

Massachusetts Air Pollution
Control Regulations

310 C.M.R.
7.00

Applicable

These regulations set emission limits
necessary to attain ambient air quality
standards, including for asbestos (7.15).

Remedial activities, including excavation and
management of NAPL and any NAPL
treatment will be implemented in accordance
with these rules. If any building demolition is
required in buildings containing asbestos,
asbestos abatement standards will be met. No
air emissions from remedial activities will
cause air quality standards to be exceeded.

Massachusetts Contingency Plan,
NAPL

310 C.M.R.
40.1003(7)

Relevant and
Appropriate

Establish standards for remedial actions
taken to adequately contain or remove
NAPL

Excavation and off-site disposal of NAPL will
address these standards, to the extent
practicable. Any remnant NAPL left in place
will be subject to monitoring/ICs to prevent
human exposure and migration to adjacent
wetlands. Any remnant NAPL may also be
addressed by the groundwater component and
soil component of the remedy.

Massachusetts Contingency Plan,
Implementation of Activity and Use
Limitations

310 C.M.R.
40.1070(4)

Relevant and
Appropriate

Establish standards for institutional controls
at CERCLA sites in Massachusetts.

Institutional controls will be established
consistent with State standards for enforceable
restrictions on contaminated property to
prevent human contact with NAPL and to
protect remedial infrastructure.

Massachusetts Water Quality
Standards Implementation Policy
for the Control of Toxic Pollutants
in Surface Waters

Feb. 1999

To Be
Considered

Guidance on controlling toxic pollutant
discharges to surface waters

This guidance will be used in the establishment
of monitoring standards for surface waters and
sediments, if required for the remedial action.

6

-------
Table D-6

Action-Specific ARARs and TBCs for NAPL
Alternative N-3: Excavation and Off-site Disposal

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Light Non Aqueous Phase Liquid
(LNAPL) and the MCP: Guidance
for Site Assessment and Closure

MassDEP
Policy
#WSC-16-
450

To Be
Considered

Guidance on assessing and remediating
LNAPL.

Excavation and off-site disposal of NAPL will
follow this guidance, to the extent practicable.
Any remnant NAPL left in place will be subject
to monitoring/ICs to prevent human exposure
and migration to adjacent wetlands. Any
remnant NAPL may also be addressed by the
groundwater component and soil component of
the remedy.

Allowable Sound

MassDEP
Division of
Air Quality
Control
Policy #90-
001

To Be
Considered

Guidance on sound emissions.

To be used to assess whether any remedial
measures exceed State noise guidance levels.

Erosion and Sediment Control
Guidance



To Be
Considered

Guidance on preventing erosion and
sedimentation.

Remedial actions will be managed to control
erosion and sedimentation.

7

-------
Table D-7

Chemical-Specific ARARs and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Safe Drinking Water Act
(SDWA); National primary
drinking water regulations,
Maximum Contaminant Levels
(MCLs)

42 U.S.C.
§ 300f et
seq:, 40
C.F.R.
141,

Subparts
B and G

Applicable

Establishes MCLs for common organic and inorganic
contaminants applicable to public drinking water
supplies. Used as relevant and appropriate standards for
aquifers and surface water bodies that are potential
drinking water sources.

Institutional controls (ICs) will prevent exposure
to groundwater that exceeds these standards
until groundwater cleanup standards are
achieved through pumping and treatment within
18 years.

Safe Drinking Water Act;
National primary drinking water
regulations, Maximum
Contaminant Level Goals
(MCLGs)

42 U.S.C.
§ 300f et
seq:, 40
C.F.R.
141,

Subpart F

Relevant and
Appropriate for
non

zero MCLGs only;
MCLGs set as
zero
are To Be
Considered.

Establishes MCLGs for public water supplies. MCLGs
are health goals for drinking water sources. These
unenforceable health goals are available for a number of
organic and inorganic compounds.

ICs will prevent exposure to groundwater that
exceeds these standards until groundwater
cleanup standards are achieved through
pumping and treatment within 18 years.

EPA Health Advisories



To Be Considered

EPA publishes contaminant-specific health advisories
that indicate the non-carcinogenic risks associated with
consuming contaminated drinking water. Used to
develop risk-based cleanup standards.

ICs will prevent exposure to groundwater that
exceeds calculated non-carcinogenic risk-based
standards developed using this guidance until
groundwater cleanup standards are achieved
through pumping and treatment within 18 years.

Guidelines for Carcinogenic Risk
Assessment

EPA/630/
P-03/001F

To Be Considered

These guidelines provide guidance on conducting risk
assessments involving carcinogens.

ICs will prevent exposure to groundwater that
exceeds calculated carcinogenic risk-based
standards developed using this guidance until
groundwater cleanup standards are achieved
through pumping and treatment within 18 years.

Supplemental Guidance for
Assessing Susceptibility from
Early-Life Exposure to
Carcinogens

EPA/630/
R-03/003F

To Be Considered

This provides guidance on assessing risk to children
from carcinogens.

ICs will prevent exposure to groundwater that
exceeds calculated carcinogenic risk-based
standards for children developed using this
guidance until groundwater cleanup standards
are achieved through pumping and treatment
within 18 years.

1

-------
Table D-7

Chemical-Specific ARARs and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

EPA Risk Reference Doses
(RfDs)



To Be Considered

Guidance used to compute human health hazard
resulting from exposure to non-carcinogens in site
media. RfDs are considered to be the levels unlikely to
cause significant adverse health effects associated with
a threshold mechanism of action in human exposure for
a lifetime.

ICs will prevent exposure to groundwater that
exceeds calculated non-carcinogenic risk-based
standards developed using this guidance until
groundwater cleanup standards are achieved
through pumping and treatment within 18 years.

Human Health Assessment
Cancer Slope Factors (CSFs)



To Be Considered

CSFs are estimates of the upper-bound probability of an
individual developing cancer as a result of a lifetime
exposure to a particular concentration of a potential
carcinogen.

ICs will prevent exposure to groundwater that
exceeds calculated carcinogenic risk-based
standards developed using this guidance until
groundwater cleanup standards are achieved
through pumping and treatment within 18 years.

EPA Carcinogenic Assessment
Group Potency Factors



To Be Considered

These factors are used to evaluate an acceptable risk
from a carcinogen.

ICs will prevent exposure to groundwater that
exceeds calculated carcinogenic risk-based
standards developed using this guidance until
groundwater cleanup standards are achieved
through pumping and treatment within 18 years.

Guidance on Remedial Actions
for Superfund Sites with
Polychlorinated Biphenyl (PCB)
Contamination

EPA-540-
G-90-007
(August
1990)

To Be Considered

EPA Guidance for evaluating risks posed by PCBs at
Superfund sites. Used to develop risk-based cleanup
standards.

ICs will prevent exposure to groundwater that
exceeds calculated risk-based standards for
PCBs in groundwater developed using this
guidance until groundwater cleanup standards
are achieved through pumping and treatment
within 18 years.

Ontario Ministry of Environment
and Energy (OMEE) Lowest
Effect Levels (LELs) for
Freshwater Sediments

(Persaud
et al.,
1993)

To Be Considered

The SEL value is the concentration at which the majority
of the sediment-dwelling organisms are not affected.
Used to develop risk-based cleanup standards.

Pump and Treat will prevent migration of
contaminated groundwater into the wetlands
which contributes to a calculated ecological risk,
developed using this guidance.

Development and Evaluation of
Consensus-Based Sediment
Quality Guidelines for
Freshwater Ecosystems.
Probable Effects Concentrations
(PECs)

(MacDona
Id et al.,
2000)

To Be Considered

The PEC value is the concentration above which the
adverse effects on sediment-dwelling organisms are
likely to occur. Used to develop risk-based cleanup
standards.

Pump and Treat will prevent migration of
contaminated groundwater into the wetlands
which contributes to a calculated ecological risk,
developed using this guidance.

-------
Table D-7

Chemical-Specific ARARs and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

State Standards









Massachusetts Drinking Water
Regulations

310

C.M.R.

22.00

Relevant and
Appropriate

Establishes maximum contaminant levels that apply to
public drinking water supplies. Massachusetts MCLs and
MCLGs are specified for numerous contaminants,
including inorganic and organic chemicals. For the most
part, the numerical criteria are identical to Federal SDWA
MCLs and MCLGs, although there are several additional
chemicals that have criteria.

ICs will prevent exposure to groundwater that
exceeds these standards until groundwater
cleanup standards are achieved through
pumping and treatment within 18 years.

-------
Table D-8

Location-Specific ARARs and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Floodplain Management
and Protection of
Wetlands

44 C.F.R. 9

Relevant
and
Appropriate

Federal Emergency Management Agency (FEMA)
regulations that set forth the policy, procedure and
responsibilities to implement and enforce Executive Order
11988 (Floodplain Management) and Executive Order
11990 (Protection of Wetlands). Prohibits activities that
adversely affect a federally-regulated wetland unless there
is no practicable alternative and the proposed action
includes all practicable measures to minimize harm to
wetlands that may result from such use. Requires the
avoidance of impacts associated with the occupancy and
modification of federally-designated 100-year and 500-year
floodplain and to avoid development within floodplain
wherever there is a practicable alternative. An assessment
of impacts to 500-year floodplain is required for critical
actions - which includes siting waste facilities in a
floodplain. Requires public notice when proposing any
action in or affecting floodplain or wetlands.

If there is no practicable alternative method to work in
federal jurisdictional wetlands while installing, maintaining
and sampling monitoring/extraction wells, access ways,
and treatment systems then all practicable measures will
be taken to minimize and mitigate any adverse impacts.
Erosion and sedimentation control measures will be
adopted during installation and maintenance activities to
protect federal jurisdictional wetlands. Standards for
installing, maintaining and sampling monitoring/extraction
wells, access ways, and treatment systems within the
regulated 500-year floodplain will be attained. After
completion of the work, there will be no significant net loss
of flood storage capacity and no significant net increase in
flood stage or velocities. Floodplain habitat will be
restored, to the extent practicable. Public comment was
solicited as part of the Proposed Plan concerning the
proposed alteration to wetlands and floodplain and no
negative comments were received.

Resource Conservation
and Recovery Act
(RCRA) Floodplain
Restrictions for
Hazardous Waste
Facilities

42 U.S.C. §§
6901 et seq
40 C.F.R. §
264.18(b)

Applicable

A hazardous waste treatment, storage, or disposal facility
located in a 100-year floodplain must be designed,
constructed, operated, and maintained to prevent washout
or to result in no adverse effects on human health or the
environment if washout were to occur.

To the extent any hazardous waste is generated from the
installation and maintenance of monitoring/extraction
wells, access ways, and treatment systems it will be
managed so that it will not impact floodplain resources.

RCRA Floodplain
Restrictions for Solid
Waste Disposal
Facilities and Practices

40 C.F.R. §
257.3-1

Applicable

Solid waste practices must not restrict the flow of a 100-
year flood, reduce the temporary water storage capacity of
the floodplain or result in washout of solid waste, so as to
pose a hazard to human life, wildlife, or land or water
resources.

Any solid waste generated from the installation and
maintenance of monitoring/extraction wells, access ways,
and treatment systems will be managed so that it will not
impact floodplain resources.

1

-------
Table D-8

Location-Specific ARARs and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Clean Water Act §404,
and regulations

33 U.S.C.
1344, 40
C.F.R. Parts
230, 231 and
33 C.F.R.
Parts 320-
323

Applicable

For discharge of dredged or fill material into water bodies or
wetlands, there must be no practical alternative with less
adverse impact on aquatic ecosystem; discharge cannot
cause or contribute to violation of state water quality
standard or toxic effluent standard or jeopardize threatened
or endangered (T&E) species; discharge cannot
significantly degrade waters of U.S.; must take practicable
steps to minimize and mitigate adverse impacts; must
evaluate impacts on flood level, flood velocity, and flood
storage capacity. Sets standards for restoration and
mitigation required as a result of unavoidable impacts to
aquatic resources. EPA must determine which alternative
is the "Least Environmentally Damaging Practicable
Alternative" (LEDPA) to protect wetland and aquatic
resources.

Under this alternative installation and maintenance of
monitoring/extraction wells, access ways, and treatment
systems may possibly impact federal jurisdictional
wetlands. Activities effecting wetlands will be conducted in
accordance with these requirements including, but not
limited to, mitigation and/or restoration. EPA has
determined that the alternative is the LEDPA because (a)
there is no practical alternative method that will achieve
cleanup objectives with less adverse impact and (b) all
practical measures would be taken to minimize and
mitigate any adverse impacts from the work. Public
comment was solicited on EPA's LEDPA finding in the
Proposed Plan and no negative comments were received.

Fish and Wildlife
Coordination Act

16 U.S.C. §§
662, 663

Applicable

Requires consultation with appropriate agencies to protect
fish and wildlife when federal actions may alter waterways.
Must develop measures to prevent and mitigate potential
loss to the maximum extent possible.

Consultation with appropriate federal agencies will be
maintained during planning and implementation ofthe
remedial alternative that may alter protected resource
areas

National Historical
Preservation Act
(NHPA)

16 U.S.C.
469 et seq. \
36 C.F.R.
Part 65

Applicable

When a federal agency finds, or is notified, that its activities
in connection with a federal construction project may cause
irreparable loss or destruction of significant scientific, pre-
historical, historical, or archeological data, the substantive
standards under the NHPA will be met.

Any undisturbed areas where monitoring/extraction wells,
access ways, and treatment systems will be constructed
will be assessed to ensure no protected resource areas
are present. If present there will be consultation with
federal and state preservation officials to address
measures to avoid, minimize and/or mitigate any impacts
to protected resource areas.

U.S. Army Corps of
Engineers, New England
District Compensatory
Mitigation Guidance (09-
07-2016)



To Be
Considered

This Guidance is to be considered when compensatory
mitigation to address impacts to federal jurisdictional
wetlands is appropriate for a particular remedial activity.

Under this alternative installation and maintenance of
monitoring/extraction wells, access ways, and treatment
systems may possibly impact federal jurisdictional
wetlands. Activities effecting federal jurisdictional
wetlands will be conducted in accordance with these
guidance standards for mitigation and/or restoration.

2

-------
Table D-8

Location-Specific ARARs and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

State Standards









Massachusetts
Wetlands Protection Act
and Regulations

MGL c. 131 §
40, 310
C.M.R. 10.00

Applicable

Regulations restrict dredging, filling, altering, or polluting
inland wetland resource areas and impose performance
standards for work in such areas (including 10.05(6)(k)
(stormwater management). Protected resource areas
include: 10.54 (Bank); 10.55 (Bordering Vegetated
Wetlands); 10.56 (Land underWater); 10.57 (Bordering
Land subject to Flooding); and 10.58 (Riverfront Area).

Under this alternative installation and maintenance of
monitoring/extraction wells, access ways, and treatment
systems may possibly impact state regulated wetland
resource areas and buffer zones. Alternatives requiring
that work be completed within 100 feet of a state regulated
wetland and 200 feet from a perennial stream will comply
with these regulations. Mitigation of impacts on State
wetland resource areas will be addressed.

Antiquities Act and
Regulations

M.G.L. ch. 9,
§§26-27; 950
C.M.R. 71.00

Relevant
and
Appropriate

Projects which are state-funded or state-licensed or which
are on state property must eliminate, limit, or mitigate
adverse effects to properties listed in the register of historic
places. Establishes coordination with the NHPA.

Any undisturbed areas where monitoring/extraction wells,
access ways, and treatment systems will be constructed
will be assessed to ensure no protected resource areas
are present. If present there will be consultation with
federal and state preservation officials to address
measures to avoid, minimize and/or mitigate any impacts
to protected resource areas.

Massachusetts
Hazardous Waste
Regulations, Location
Standards for Land
Subject to Flooding

310 C.M.R.
30.701

Applicable

Any new or expanding hazardous waste storage or
treatment facility (which only receives hazardous waste
from on-site sources), the active portion of which is located
within the boundary of land subject to flooding from the
statistical 100-year frequency storm, shall be flood-proofed.
Flood-proofing shall be designed, constructed, operated
and maintained to prevent floodwaters from coming into
contact with hazardous waste.

To the extent any hazardous waste is generated from the
installation and maintenance of monitoring
wells/extraction, access ways, and treatment systems it
will be managed so that it will not impact floodplain
resources.

3

-------
Table D-9

Action-Specific and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls
Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Resource Conservation and
Recovery Act (RCRA) Subtitle
C; Hazardous Waste
Identification and Listing
Regulations; Generator and
Handler Requirements, Closure
and Post-Closure

42 U.S.C. §6901
et seq.; 40
C.F.R. Parts
260-262 and
264

Applicable

Federal standards used to identify,
manage, and dispose of hazardous waste.
Massachusetts has been delegated the
authority to administer these RCRA
standards through its state hazardous
waste management regulations. These
provisions have been adopted by the
State. Federal financial assurance
requirements are defined at 40 C.F.R.
264.143.

Any wastes generated by remedial activity will be analyzed
under these standards to determine whether they are listed
or characteristic hazardous waste. Non-hazardous materials
will be disposed appropriately. Any discharges and filter
media from the pump and treat system, as well as
contaminated soil/sediment from extraction/monitoring well
drilling or maintenance, meeting either listed or characteristic
hazardous waste standards will be disposed of off-site at a
licensed facility. Releases from regulated hazardous waste
facilities will be addressed under applicable closure/post
closure standards, including financial assurance
requirements.

RCRA, Air Emission Standards
for Process Vents

40 C.F.R. Part
264, Subpart AA

Applicable, if
volatile organic

compounds
(VOC) emissions
over 10 parts per
million (ppm) or
greater; Relevant
and Appropriate,
if less than 10
ppm

RCRA emissions standards not delegated
to the State. Standards for process vents
for air treatment systems for RCRA wastes
that have total organic concentrations of
10 ppm or greater.

If air treatment of VOCs is required, emission standards for
any process vents, if present, will be achieved.

RCRA, Air Emission Standards
for Equipment Leaks

40 C.F.R. Part
264, Subpart BB

Applicable, if
VOC emissions
over10 ppm or
greater; Relevant
and Appropriate,
if less than 10
ppm

RCRA emissions standards not delegated
to the State. Standards for preventing air
equipment leaks for systems that treat
RCRA wastes that have total organic
concentrations of 10 ppm or greater.

Standards for preventing air emission leaks from treatment
systems for VOCs will be achieved.

1

-------
Table D-9

Action-Specific and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls
Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Toxic Substances Control Act
(TSCA); Polychlorinated
biphenyl (PCB) Remediation
Waste

15 U.S.C. 2601
et seq.; 40
C.F.R. 761.61(c)

Applicable

This section of the TSCA regulations
provides risk-based cleanup and disposal
options for PCB remediation waste based
on the risks posed by the concentrations at
which the PCBs are found. Written
approval for the proposed risk-based
cleanup must be obtained from the
Director, Office of Site Remediation and
Restoration, USEPA Region 1.

Any PCB contaminated soil/sediment from extraction/
monitoring well drilling or maintenance, as well as any PCB
contaminated discharge or filter media from the pump and
treat system, exceeding human health risk standards or
ecological risk standards will be disposed of off-site.
Institutional controls will prevent residential exposure to PCB-
contaminated groundwater until the pump and treat system
achieves unrestricted use standards. Remedial measures
will be based on in-situ PCB concentrations in soil/sediment/
groundwater. EPA has issued a determination (Appendix E)
that the selected remedy will not pose an unreasonable risk
of injury to health or the environment as long as required
protective conditions in the determination are met.

Clean Water Act; National
Pollutant Discharge Elimination
System (NPDES)

40 C.F.R. Parts
122 and 125

Applicable

Establishes the specifications for
discharging pollutants from any point
source into the waters of the United States
(U.S.). Also, includes stormwater
standards for activities disturbing more
than one acre.

Any water generated from the pump and treat system and
during installation and management of monitoring/extraction
wells will be treated to meet NPDES standards if the water is
to be discharged to surface waters.

Clean Water Act; Toxic Pollutant
Effluent Standards

40 CFR 129

Applicable

Regulates surface water discharges of
specific toxic pollutants, specifically certain
pesticides and PCBs.

Any water generated from the pump and treat system and
during installation and management of monitoring/extraction
wells will be treated to meet applicable toxic pollutant
discharge standards (if regulated contaminants are present)
if the water is to be discharged to surface waters.

Clean Water Act; General
Pretreatment Regulations for
Existing and New Sources of
Pollution

33 U.S.C. §
1251 et seq. ] 40
C.F.R. § 403

Applicable

Standards for discharge into a Publicly
Owned Treatment Works (POTW).

Any water generated from the pump and treat system and
during installation and management of monitoring/extraction
wells will be treated to pretreatment standards if the water is
to be discharged to a POTW.

Clean Water Act, National
Recommended Water Quality
Criteria (NRWQC)

33 U.S.C. §
1314, 40 CFR
Part 131

Relevant and
Appropriate

NRWQC are provided by EPA for
chemicals for both the protection of human
health and the protection of aquatic life.

Used to establish monitoring standards for surface waters
and sediments, if required for the remedial action.

2

-------
Table D-9

Action-Specific and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls
Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Clean Air Act (CAA), Hazardous
Air Pollutants; National Emission
Standards for Hazardous Air
Pollutants (NESHAPS)

42.U.S.C. §
112(b)(1); 40
C.F.R. Part 61

Applicable

The regulations establish emissions
standards for 189 hazardous air pollutants.
Standards set for dust and other release
sources.

Remedial activities, including air discharges from the pump
and treat system and excavation and management of
monitoring/extraction wells, will be implemented in
accordance with these rules. No air emissions from remedial
activities will cause air quality standards to be exceeded.
Dust standards will be complied with during excavation and
management of materials within the OU.

Safe Drinking Water Act;
National primary drinking water
regulations, Maximum
Contaminant Levels

42 U.S.C. § 300f
et seq.; 40
C.F.R. 141,
Subparts B and
G

Applicable

Federal drinking waters standards used as
groundwater monitoring standards when
contaminated media left in place.

Standards used as groundwater monitoring standards until
groundwater cleanup is achieved.

Safe Drinking Water Act;
National primary drinking water
regulations, Maximum
Contaminant Level Goals

42 U.S.C. § 300f
et seq. ] 40
C.F.R. 141,
Subpart F

Relevant and
Appropriate for
non zero MCLGs
only; MCLGs set
as zero are To Be
Considered.

Federal drinking waters standards used as
groundwater monitoring standards when
contaminated media left in place.

Standards used as groundwater monitoring standards until
groundwater cleanup is achieved.

EPA Health Advisories



To Be
Considered

Federal risk-based standards for
groundwater used as groundwater
monitoring standards when contaminated
media left in place.

Risk-based standards developed using these advisories
used as groundwater monitoring standards until groundwater
cleanup is achieved.

Summary of Key Existing EPA
Comprehensive Environmental
Response Compensation and
Liability Act (CERCLA) Policies
for Groundwater Restoration

OSWER
Directive
9283.1-33
(June 26, 2009)

To Be
Considered

Guidance on developing groundwater
remedies at CERCLA sites.

Groundwater remediation standards called for in this
guidance will be satisfied as long as groundwater cleanup
will be achieved through operating the pump and treat
system within 18 years and Institutional Controls (ICs) are
established that will prevent exposure to contaminated
groundwater until cleanup standards are achieved.

Generation of investigation
derived waste.

USEPA OSWER
Publication
9345.3-03 FS
(January 1992)

To Be
Considered

Guidance on the management of
Investigation-Derived Waste (IDW) in a
manner that ensures protection of human
health and the environment.

IDW generated as part of this remedial alternative will be
managed based on guidance standards.

3

-------
Table D-9

Action-Specific and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls
Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

OSWER Technical Guide for
Assessing and Mitigating the
Vapor Intrusion Pathway from
Subsurface Vapor Sources to
Indoor Air.

OSWER
Publication
9200.2-154
(June 2015)

To Be
Considered

EPA guidance for addressing vapor
intrusion issues at CERCLA sites.

Institutional controls will be implemented to prevent potential
vapor exposures until groundwater cleanup standards are
achieved through operation of the pump and treat system.

State Standards









Massachusetts Hazardous
Waste Rules for Identification
and Listing of Hazardous
Wastes

310 C.M.R.
30.100

Applicable

Massachusetts is delegated to administer
RCRA through its State regulations.

These regulations establish requirements
for determining whether wastes are either
listed or characteristic hazardous waste.

Any wastes generated by remedial activity will be analyzed
under these standards to determine whether they are listed
or characteristic hazardous waste. Non-hazardous materials
will be disposed appropriately. Any discharges and filter
media from the pump and treat system, as well as
contaminated soil/sediment from extraction/monitoring well
drilling or maintenance, meeting either listed or characteristic
hazardous waste standards will be disposed of off-site at a
licensed facility.

Massachusetts Hazardous
Waste Management Rules -
Requirements for Generators

310 C.M.R.
30.300

Applicable

These regulations contain requirements for
generators of hazardous waste. The
regulations apply to generators of
sampling waste and also apply to the
accumulation of waste prior to off-site
disposal

If any remedial activity generates hazardous wastes, the
waste will be managed in accordance with the substantive
requirements of these regulations.

Massachusetts Hazardous
Waste Management Rules -
General standards for
hazardous waste facilities

310 C.M.R.
30.500

Applicable

General facility requirements for waste
analysis, security measures, inspections,
and training requirements. Section 30.580
addresses closure and Section 30.590
post-closure of hazardous waste facilities.

If any remedial activity generates hazardous wastes, on-site
facilities used to handle the waste will be managed in
accordance with the substantive requirements of these
regulations.

Massachusetts Hazardous
Waste Rules - Special
requirements for wastewater
treatment units

310 C.M.R.
30.605

Relevant and
Appropriate

Standards for wastewater treatment units
for the treatment of hazardous waste.

Any water generated during operation of the pump and treat
system or during extraction/monitoring well drilling or
maintenance that meets hazardous waste standards will be
treated to meet pretreatment standards, if the water is to be
discharged to a Publically Owned Treatment Works (POTW).

Massachusetts Hazardous
Waste Rules - Groundwater
Protection

310 C.M.R.
30.660

Relevant and
Appropriate

Hazardous waste facility standards for the
protection of groundwater.

Any hazardous waste generated by the remedial alternative
will be managed to prevent contaminant migration to
groundwater.

4

-------
Table D-9

Action-Specific and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls
Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Hazardous
Waste Rules - Containers

310 C.M.R.
30.680

Applicable

Establishes requirements for the
management of containers, such as
drums, that would hold field-generated
hazardous wastes.

If any remedial activity generates hazardous wastes that will
be stored in containers, the containers will be managed in
accordance with the substantive requirements of these
regulations.

Massachusetts Hazardous
Waste Rules - Management,
Storage, and Treatment in
Tanks

310 C.M.R.
30.690

Applicable

These standards specify requirements for
tank systems used to store or treat
hazardous waste. Provides specifications
for design and installation of tank systems.
Requires secondary containment, leak
detection systems, and inspections.
Identifies general operating requirements,
and closure and post-closure care.

If any remedial activity generates hazardous wastes that will
be stored in tanks, the tanks will be managed in accordance
with the substantive requirements of these regulations.

Massachusetts Supplemental
Requirements for Hazardous
Waste Management Facilities

314 C.M.R.
8.03

Relevant and
Appropriate

This regulation outlines the additional
requirements that must be satisfied in
order for a RCRA facility to comply with
the NPDES regulation.

Any water generated during operation of the pump and treat
system or during extraction/monitoring well drilling or
maintenance that meets hazardous waste standards will be
treated to meet NPDES standards, if the water is to be
discharged to surface waters.

Massachusetts Clean Water
Act; Surface Water Discharge
Permit Regulations

M.G.L. ch 21, §§
26-53; 314
C.M.R. 3.00

Applicable

These regulations provide that discharges
to waters of the Commonwealth shall not
result in exceedances of MA Surface
Water Quality Standards (MSWQS).

Any water generated during operation of the pump and treat
system or during extraction/monitoring well drilling or
maintenance will be treated to meet discharge standards if
discharged to surface waters.

Operation and Maintenance and
Pretreatment Standards for
Wastewater T reatment Works
and Indirect Dischargers

314 C.M.R.
12.03(6-7),(9);
12.04(3),(6-
14); 12.05(1 ),(6).
(12-13); 12.06(1-
3)

Applicable

Standards for the operation of waste water
treatment works.

The water treatment system for the pump and treat system
will be operated and maintained in compliance with these
standards.

Prohibitions and Standards for
Discharges to POTWs

314 C.M.R.
12.08

Applicable

Standards for discharge into a Publicly
Owned Treatment Works (POTW).

Any water generated from the pump and treat system and
during installation and management of monitoring/extraction
wells will be treated to pretreatment standards if the water is
to be discharged to a POTW.

5

-------
Table D-9

Action-Specific and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls
Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Clean Water
Act; MA Surface Water Quality
Standards (MSWQS)

M.G.L. ch 21, §§
26-53; 314
C.M.R. 4.00)

Relevant and
Appropriate

These standards designate the most
sensitive uses for which the various waters
of the Commonwealth shall be enhanced,
maintained, or protected. Minimum water
quality criteria required to sustain the
designated uses are established.

Used to establish monitoring standards for surface waters
and sediments, if required for the remedial action.

Massachusetts Drinking Water
Regulations

310 C.M.R.
22.00

Relevant and
Appropriate

Establishes maximum contaminant levels
that apply to public drinking water
supplies. Massachusetts Maximum
Contaminant Levels (MCLs) and Maximum
Contaminant Level Goals (MCLGs) are
specified for numerous contaminants,
including inorganic and organic chemicals.
For the most part, the numerical criteria
are identical to Federal Safe Drinking
Water Act (SDWA) MCLs and MCLGs,
although there are several additional
chemicals that have criteria.

Standards used as groundwater monitoring standards until
groundwater cleanup is achieved.

Massachusetts Ambient Air
Quality Standards

310 C.M.R.
6.00

Applicable

Sets primary and secondary standards for
emissions of certain contaminants,
including particulate matter.

Remedial activities, including air discharges from the pump
and treat system and excavation and management of
monitoring/extraction wells, will be implemented in
accordance with these rules. No air emissions from remedial
activities will cause air quality standards to be exceeded.
Dust standards will be complied with during excavation and
management of materials at the Site.

Massachusetts Air Pollution
Control Regulations

310 C.M.R.
7.00

Applicable

These regulations set emission limits
necessary to attain ambient air quality
standards.

Remedial activities, including air discharges from the pump
and treat system and excavation and management of
monitoring/extraction wells, will be implemented in
accordance with these rules. No air emissions from remedial
activities will cause air quality standards to be exceeded.

Massachusetts Contingency
Plan, Implementation of Activity
and Use Limitations

310 C.M.R.
40.1070(4)

Relevant and
Appropriate

Establish standards for institutional
controls at CERCLA sites in
Massachusetts.

Institutional controls would be established consistent with
State standards for enforceable restrictions on contaminated
property to prevent human contact with contaminated
groundwater until groundwater cleanup standards are
achieved.

6

-------
Table D-9

Action-Specific and TBCs for SWP-Wide Groundwater
Alternative GW-6: Pump and Treat and Institutional Controls
Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Water Quality
Standards Implementation
Policy for the Control of Toxic
Pollutants in Surface Waters

Feb. 1999

To Be
Considered

Guidance on controlling toxic pollutant
discharges to surface waters

This guidance will be used in the establishment of monitoring
standards for surface waters and sediments, if required for
the remedial action.

Allowable Sound

Air Quality
Control Policy
#90-001

To Be
Considered

Guidance on sound emissions.

To be used to assess whether any remedial measures
exceed State noise guidance levels.

Massachusetts Standard
References for Monitoring Wells

WSC-310-91

To Be
Considered

Guidance on locating, drilling, installing,
sampling and decommissioning monitoring
wells.

Monitoring wells will be established, maintained, and
decommissioned in accordance with these guidance
standards.

Erosion and Sediment Control
Guidance



To Be
Considered

Guidance on preventing erosion and
sedimentation.

Remedial actions will be managed to control erosion and
sedimentation.

7

-------
Table D-10

Chemical-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Guidelines for Carcinogenic Risk
Assessment

EPA/630/P-
03/001F

To Be
Considered

These guidelines provide guidance on
conducting risk assessments involving
carcinogens.

Excavation and off-site disposal will prevent human contact
with wetland soils/sediments that exceed calculated
carcinogenic risk-based standards developed using this
guidance.

Supplemental Guidance for
Assessing Susceptibility from Early-
Life Exposure to Carcinogens

EPA/630/R-
03/003F

To Be
Considered

This provides guidance on assessing risk
to children from carcinogens.

Excavation and off-site disposal will prevent human contact
with wetland soils/sediments that exceed calculated
carcinogenic risk-based standards for children developed using
this guidance.

EPA Risk Reference Doses (RfDs)



To Be
Considered

Guidance used to compute human health
hazard resulting from exposure to non-
carcinogens in site media. RfDs are
considered to be the levels unlikely to
cause significant adverse health effects
associated with a threshold mechanism of
action in human exposure for a lifetime.

Excavation and off-site disposal will prevent human contact
with wetland soils/sediments that exceed calculated non-
carcinogenic risk-based standards developed using this
guidance.

Human Health Assessment Cancer
Slope Factors (CSFs)



To Be
Considered

CSFs are estimates of the upper-bound
probability of an individual developing
cancer as a result of a lifetime exposure to
a particular concentration of a potential
carcinogen.

Excavation and off-site disposal will prevent human contact
with wetland soils/sediments that exceed calculated
carcinogenic risk-based standards developed using this
guidance.

EPA Carcinogenic Assessment
Group Potency Factors



To Be
Considered

These factors are used to evaluate an
acceptable risk from a carcinogen.

Excavation and off-site disposal will prevent human contact
with wetland soils/sediments that exceed calculated
carcinogenic risk-based standards developed using this
guidance.

Updated Scientific Considerations
for Lead in Soil Cleanups

EPA OLEM

Directive

9200.2-167

To Be
Considered

EPA Guidance for evaluating risks posed
by lead in soil. Used to develop site-
specific risk-based standards.
Recommends evaluating potential risks
from exposures to lead at a Superfund site
at a target blood lead level lower than 10
ug/dL.

Excavation and off-site disposal will prevent human contact
with lead-contaminated wetland soils/sediments that exceed
calculated risk-based standards developed using this guidance.

1

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Table D-10

Chemical-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Recommendations of
the Technical Review Workgroup
for Lead for an approach to
Assessing Risks Associated with
Adult Exposure to Lead In Soil

EPA-540-R-
03-001
(January
2003)

To Be
Considered

EPA Guidance for evaluating risks posed
by lead in soil.

Excavation and off-site disposal will prevent human contact
with lead-contaminated wetland soils/sediments that exceed
calculated risk-based standards developed using this guidance.

Guidance on Remedial Actions for
Superfund Sites with PCB
Contamination

EPA-540-G-
90-007
(August
1990)

To Be
Considered

EPA Guidance for evaluating risks posed
by PCBs at Superfund sites. Used to
develop risk-based cleanup standards.

Excavation and off-site disposal will prevent human and
ecological contact with PCB-contaminated wetland
soils/sediments that exceed risk-based standards developed
based on this guidance.

Ontario Ministry of Environment and
Energy (OMEE) Lowest Effect
Levels (LELs) for Freshwater
Sediments

(Persaud et
at., 1993)

To Be
Considered

The SEL value is the concentration at
which the majority of the sediment-
dwelling organisms are not affected. Used
to develop risk-based cleanup standards.

Excavation and off-site disposal will prevent ecological contact
with wetland soils/sediments that exceed calculated ecological
risk-based standards developed using this guidance.

Development and Evaluation of
Consensus-Based Sediment
Quality Guidelines for Freshwater
Ecosystems. Probable Effects
Concentrations (PECs)

(MacDonald
et at.,

2000)

To Be
Considered

The PEC value is the concentration above
which the adverse effects on sediment-
dwelling organisms are likely to occur.
Used to develop risk-based cleanup
standards.

Excavation and off-site disposal will prevent ecological contact
with wetland soils/sediments that exceed calculated ecological
risk-based standards developed using this guidance.

2

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Table D-ll

Location-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Floodplain
Management and
Protection of
Wetlands

44 C.F.R. 9

Relevant
and
Appropriate

FEMA regulations that set forth the policy, procedure and
responsibilities to implement and enforce Executive Order 11988
(Floodplain Management) and Executive Order 11990 (Protection of
Wetlands). Prohibits activities that adversely affect a federally-
regulated wetland unless there is no practicable alternative and the
proposed action includes all practicable measures to minimize harm
to wetlands that may result from such use. Requires the avoidance
of impacts associated with the occupancy and modification of
federally-designated 100-year and 500-year floodplain and to avoid
development within floodplain wherever there is a practicable
alternative. An assessment of impacts to 500-year floodplain is
required for critical actions - which includes siting waste facilities in a
floodplain. Requires public notice when proposing any action in or
affecting floodplain or wetlands.

Federal jurisdictional wetlands altered by wetland
soil/sediment excavation/ management and
excavation dewatering will be restored in place.
The wetland will be backfilled to its original grade.
All remedial work within the regulated 500-year
floodplain will result in no significant net loss of
flood storage capacity and no significant net
increase in flood stage or velocities. Floodplain
habitat will be restored, to the extent practicable.
Public comment was solicited as part of the
Proposed Plan concerning the proposed alteration
to wetlands and floodplain and comments
concerning the wetland excavation component to
the remedy were addressed in the
Responsiveness Summary (Part 3).

Clean Water Act
§404, and regulations

33 U.S.C.
1344, 40
C.F.R. Parts
230, 231 and
33 C.F.R. Parts
320-323

Applicable

For discharge of dredged or fill material into water bodies or
wetlands, there must be no practical alternative with less adverse
impact on aquatic ecosystem; discharge cannot cause or contribute
to violation of state water quality standard or toxic effluent standard
or jeopardize threatened or endangered (T&E) species; discharge
cannot significantly degrade waters of U.S.; must take practicable
steps to minimize and mitigate adverse impacts; must evaluate
impacts on flood level, flood velocity, and flood storage capacity.
Sets standards for restoration and mitigation required as a result of
unavoidable impacts to aquatic resources. EPA must determine
which alternative is the "Least Environmentally Damaging
Practicable Alternative" (LEDPA) to protect wetland and aquatic
resources.

Under this alternative dredging/excavation of the
wetland soil/sediment and its management on-site,
will impact federal jurisdictional wetlands.

Activities effecting wetlands will be conducted in
accordance with these requirements including, but
not limited to, mitigation and/or restoration in
place. The wetland will be backfilled to its original
grade. EPA has determined this alternative is the
LEDPA because (a) there is no practical
alternative method that will achieve cleanup
objectives with less adverse impact and (b) all
practical measures would be taken to minimize
and mitigate any adverse impacts from the work.
Public comment was solicited on EPA's LEDPA
finding in the Proposed Plan and comments
concerning the wetland excavation component to
the remedy were addressed in the
Responsiveness Summary (Part 3).

1

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Table D-ll

Location-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Resource
Conservation and
Recovery Act (RCRA)
Floodplain
Restrictions for
Hazardous Waste
Facilities

42 U.S.C. §§
6901 et seq
40 C.F.R. §
264.18(b)

Applicable

A hazardous waste treatment, storage, or disposal facility located in
a 100-year floodplain must be designed, constructed, operated, and
maintained to prevent washout or to result in no adverse effects on
human health or the environment if washout were to occur.

Any hazardous waste generated from the
excavation and water treatment activities will be
managed so that it will not impact floodplain
resources.

RCRA Floodplain
Restrictions for Solid
Waste Disposal
Facilities and
Practices

40 C.F.R. §
257.3-1

Applicable

Solid waste practices must not restrict the flow of a 100-year flood,
reduce the temporary water storage capacity of the floodplain or
result in washout of solid waste, so as to pose a hazard to human
life, wildlife, or land or water resources.

Any solid waste generated from the excavation
and water treatment activities will be managed so
that it will not impact floodplain resources.

Fish and Wildlife
Coordination Act

16 U.S.C. §§
662, 663

Applicable

Requires consultation with appropriate agencies to protect fish and
wildlife when federal actions may alter waterways. Must develop
measures to prevent and mitigate potential loss to the maximum
extent possible.

Consultation with appropriate federal agencies will
be maintained during planning and implementation
of the alternative since it will alter protected
resource areas.

National Historical
Preservation Act,

16 U.S.C. 469
et seq.; 36
C.F.R. Part 65

Applicable

When a federal agency finds, or is notified, that its activities in
connection with a federal construction project may cause irreparable
loss or destruction of significant scientific, pre-historical, historical, or
archeological data, the substantive standards under the Act will be
met.

Any undisturbed areas altered by the sediment
excavation or management activities will be
assessed to ensure no protected resource areas
are present. If present there will be consultation
with federal and state preservation officials to
address measures to avoid, minimize and/or
mitigate any impacts to protected resource areas.

2

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Table D-ll

Location-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

U.S. Army Corps of
Engineers, New
England District
Compensatory
Mitigation Guidance
(09-07-2016)



To Be
Considered

This Guidance is to be considered when compensatory mitigation to
address impacts to federal jurisdictional wetlands is appropriate for a
particular remedial activity.

Under this alternative dredging/excavation of the
wetland soil/sediment and its management on-site,
will impact federal jurisdictional wetlands.

Activities effecting federal jurisdictional wetlands
will be conducted in accordance with these
guidance standards for mitigation and/or
restoration.

State Standards









Massachusetts
Wetlands Protection
Act and Regulations

MGL c. 131 §
40, 310 C.M.R.
10.00

Applicable

Regulations restrict dredging, filling, altering, or polluting inland
wetland resource areas and impose performance standards for work
in such areas (including 10.05(6)(k) (stormwater management).
Protected resource areas include: 10.54 (Bank); 10.55 (Bordering
Vegetated Wetlands); 10.56 (Land underWater); 10.57 (Bordering
Land subject to Flooding); and 10.58 (Riverfront Area).

State jurisdictional wetland resource areas altered
by wetland soil/sediment excavation/management
and excavation dewatering will be restored in
place. The wetland will be backfilled to its original
grade. All remedial action conducted within 100
feet of a state wetland and 200 feet from a
perennial stream will comply with these
regulations. There will be no loss of flood storage
capacity within Bordering Land Subject to Flooding
since the excavation will be backfilled to the
original grade of the wetland. Mitigation of impacts
on State wetland resource areas will be
addressed.

Massachusetts
Hazardous Waste
Regulations, Location
Standards for Land
Subject to Flooding

310 C.M.R.
30.701

Applicable

Any new or expanding hazardous waste storage or treatment facility
(which only receives hazardous waste from on-site sources), the
active portion of which is located within the boundary of land subject
to flooding from the statistical 100-year frequency storm, shall be
floodproofed. Floodproofing shall be designed, constructed, operated
and maintained to prevent floodwaters from coming into contact with
hazardous waste.

Any hazardous waste generated from the
excavation and water treatment activities will be
managed so that it will not impact floodplain
resources.

3

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Table D-ll

Location-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Clean
Water Act; Water
Quality Certification
for Discharge of
Dredged or Fill
Material

M.G.L. ch.21,
§§ 26-53; 314
C.M.R. §9.00

Applicable

Regulates discharges of dredged or fill material to protect aquatic
ecosystems.

Under this alternative dredging/filling of wetlands
during wetland soil/sediment excavation/
management and backfilling will be conducted so
as to not impair surface water quality.

Antiquities Act and
Regulations

M.G.L. ch. 9,
§§26-27; 950
C.M.R. 71.00

Relevant
and
Appropriate

Projects which are state-funded or state-licensed or which are on
state property must eliminate, limit, or mitigate adverse effects to
properties listed in the register of historic places. Establishes
coordination with the National Historic Preservation Act.

Any undisturbed areas altered by the wetland
soil/sediment excavation or management activities
will be assessed to ensure no protected resource
areas are present. If present there will be
consultation with federal and state preservation
officials to address measures to avoid, minimize
and/or mitigate any impacts to protected resource
areas.

4

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D-12

Action-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Federal Standards









Resource Conservation and
Recovery Act (RCRA)
Subtitle C; Hazardous
Waste Identification and
Listing Regulations;
Generator and Handler
Requirements, Closure and
Post-Closure

42 U.S.C.
§6901 efseq.;
40 C.F.R.
Parts 260-262
and 264

Relevant and Appropriate
for undisturbed
hazardous waste;
Applicable for any new
hazardous waste
management

Federal standards used to identify, manage, and
dispose of hazardous waste. Massachusetts has
been delegated the authority to administer these
RCRA standards through its state hazardous waste
management regulations. These provisions have
been adopted by the State. Federal financial
assurance requirements are defined at 40 C.F.R.
264.143.

Any wastes generated by wetland soil/sediment
excavation and water treatment will be analyzed
under these standards to determine whether they
are listed or characteristic hazardous waste.
Excavation of any hazardous waste present will
need to meet closure/post closure standards,
including financial assurance requirements.

Toxic Substances Control
Act (TSCA); PCB
Remediation Waste

15 U.S.C.
2601 et seq.;
40 C.F.R.
761.61(c)

Applicable

This section of the TSCA regulations provides risk-
based cleanup and disposal options for PCB
remediation waste based on the risks posed by the
concentrations at which the PCBs are found.
Written approval for the proposed risk-based
cleanup must be obtained from the Director, Office
of Site Remediation and Restoration, USEPA
Region 1.

The Record of Decision contains a finding by EPA
(Appendix E) that the complete excavation and
off-site disposal of all PCB-contaminated wetland
soil/sediment above human health and ecological
risk levels and treatment of water generated from
the excavation/dewatering of excavated
soil/sediment will prevent an unreasonable risk to
human health or the environment as long as
required protective conditions in the determination
are met. All PCB-contaminated wetland
soil/sediment exceeding human health risk
standards or ecological risk standards will be
excavated and disposed of off-site at a licensed
facility. Any water generated from the remedial
action that exceeds EPA risk standards will be
treated to meet protective PCB discharge limits.
Remedial measures will be based on in-situ PCB
concentrations in sediment.

1

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D-12

Action-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Clean Water Act, National
Recommended Water
Quality Criteria

33 U.S.C. §
1314, 40 CFR
Part 131

Relevant and Appropriate

NRWQC are provided by EPA for chemicals for
both the protection of human health and the
protection of aquatic life.

Used to establish monitoring standards for
surface waters and sediments to assess the
protectiveness ofthe excavation and sediment
management remedial actions.

Clean Water Act; National
Pollutant Discharge
Elimination System
(NPDES)

40 C.F.R.
Parts 122 and
125

Applicable

Establishes the specifications for discharging
pollutants from any point source into the waters of
the U.S. Also, includes stormwater standards for
activities disturbing more than one acre.

Any discharges from wetland soil/sediment
excavation/management and excavation
dewatering will be treated to meet these
standards before discharge to surface waters.
Stormwater standard will be met if there is over
one acre of work.

Clean Water Act; Toxic
Pollutant Effluent Standards

40 CFR 129

Applicable

Regulates surface water discharges of specific toxic
pollutants, specifically certain pesticides and PCBs.

Any discharges from wetland soil/sediment
excavation/management and excavation
dewatering will be treated to meet these
standards before discharge to surface waters.

Clean Air Act (CAA),
Hazardous Air Pollutants;
National Emission
Standards for Hazardous
Air Pollutants (NESHAPS)

42.U.S.C. §
112(b)(1); 40
C.F.R. Part 61

Applicable

The regulations establish emissions standards for
189 hazardous air pollutants. Standards set for
dust and other release sources.

Emission standards, including for dust, will be
achieved during sediment excavation/
management and water treatment.

Generation of investigation
derived waste.

OSWER
9345.3-03 FS
(1992)

To Be Considered

Guidance on the management of Investigation-
Derived Waste (IDW) in a manner that ensures
protection of human health and the environment.

IDW generated as part of this remedial alternative
will be managed based on guidance standards.

Contaminated Sediment
Remediation Guidance for
Hazardous Waste Sites

EPA-540-R-

05-012

OSWER

9355.0-85

(December

2005)

To Be Considered

Guidance for making remedy decisions for
contaminated sediment sites. Some of the relevant
sections ofthe guidance address Remedial
Investigations (Ch. 2), FS Considerations (Ch. 3),
Monitored Natural Recovery (Ch. 4), In-Situ
Capping (Ch. 5), and Dredging and Excavation (Ch.
6).

Sediment remediation standards called for in this
guidance pertaining to dredging/excavation will be
achieved.

2

-------
D-12

Action-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Remediating Contaminated
Sediment Sites -
Clarification of Several Key
Remedial Investigation/
Feasibility Study and Risk
Management
Recommendations, and
Updated Contaminated
Sediment Technical
Advisory Group Operating
Procedures

OLEM

Directive

9200.1-130

(January
2017)

To Be Considered

This guidance identifies eleven recommendations
based on current best practices for characterizing
sediment sites, evaluating remedial alternatives,
and selecting and implementing appropriate
response actions.

Sediment remediation standards called for in this
guidance pertaining to excavation remedies will
be achieved.

State Standards









Massachusetts Hazardous
Waste Rules for
Identification and Listing of
Hazardous Wastes

310 C.M.R.
30.100

Relevant and Appropriate
for undisturbed
hazardous waste;
Applicable for any new
hazardous waste
management

Massachusetts is delegated to administer RCRA
through its State regulations. These regulations
establish requirements for determining whether
wastes are either listed or characteristic hazardous
waste.

Any wastes generated by wetland soil/sediment
excavation and water treatment will be analyzed
under these standards to determine whether they
are listed or characteristic hazardous waste.

Massachusetts Hazardous
Waste Management Rules -
Requirements for
Generators

310 C.M.R.
30.300

Applicable

These regulations contain requirements for
generators of hazardous waste. The regulations
apply to generators of sampling waste and also
apply to the accumulation of waste prior to off-site
disposal.

If any remedial activity generates hazardous
wastes, the waste will be managed in accordance
with the substantive requirements of these
regulations.

Massachusetts Hazardous
Waste Management Rules -
General standards for
hazardous waste facilities

310 C.M.R.
30.500

Relevant and Appropriate
for non-listed waste left in
place; Applicable for
listed wastes that still
display hazardous
characteristics or for
hazardous wastes
generated as part of a
cleanup (e.g., excavated
soil/sediment)

General facility requirements for waste analysis,
security measures, inspections, and training
requirements. Section 30.580 addresses closure
and Section 30.590 post-closure of hazardous
waste facilities.

If hazardous waste is managed prior of off-site
disposal these facility standards will be met.

3

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D-12

Action-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Hazardous
Waste Rules, Groundwater
protection

310 C.M.R.
30.660

Relevant and Appropriate

Hazardous waste facility standards for the
protection of groundwater.

If hazardous waste is managed prior to off-site
disposal the remedial action must prevent
migration of contaminants into groundwater.

Massachusetts Hazardous
Waste Rules - Containers

310 C.M.R.
30.680

Applicable

Establishes requirements for the management of
containers, such as drums, that would hold field-
generated hazardous wastes.

If any remedial activity generates hazardous
wastes that will be stored in containers, the
containers will be managed in accordance with
the substantive requirements of these regulations.

Massachusetts Hazardous
Waste Rules -
Management, Storage, and
Treatment in Tanks

310 C.M.R.
30.690

Applicable

These standards specify requirements for tank
systems used to store or treat hazardous waste.
Provides specifications for design and installation of
tank systems. Requires secondary containment,
leak detection systems, and inspections. Identifies
general operating requirements, and closure and
post-closure care.

If any remedial activity generates hazardous
wastes that will be stored in tanks, the tanks will
be managed in accordance with the substantive
requirements of these regulations.

Massachusetts Clean
Water Act; Surface Water
Discharge Permit
Regulations

M.G.L. ch 21,
§§ 26-53; 314
C.M.R. 3.00

Applicable

These regulations provide that discharges to waters
of the Commonwealth shall not result in
exceedances of MA Surface Water Quality
Standards (MSWQS).

Any discharges from wetland soil/sediment
excavation/ management and excavation
dewatering will be treated to meet these
standards before discharge to surface waters.
Stormwater standard will be met if there is over
one acre of work.

Massachusetts Clean
Water Act; MA Surface
Water Quality Standards
(MSWQS)

M.G.L. ch 21,
§§ 26-53; 314
C.M.R. 4.00)

Relevant and Appropriate

These standards designate the most sensitive uses
for which the various waters of the Commonwealth
shall be enhanced, maintained, or protected.
Minimum water quality criteria required to sustain
the designated uses are established.

Used to establish monitoring standards for
surface waters and sediments to assess the
protectiveness of the excavation and sediment
management remedial actions.

Operation and Maintenance
and Pretreatment
Standards for Wastewater
Treatment Works and
Indirect Dischargers

314 C.M.R.
12.03(6-7),(9);
12.04(3),(6-
14); 12.05( 1),(
6).(12-13);
12.06(1-3)

Applicable

Standards for the operation of waste water
treatment works.

The water treatment system for the water
treatment system will be operated and maintained
in compliance with these standards.

4

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D-12

Action-Specific ARARs and TBCs for Sediment/Soil at the Murphy Wetland
Alternative WTL5: Deep (3 feet) Excavation and Off-site Disposal, Backfill and Wetland Restoration

Wells G&H Superfund Site, Southwest Properties, Operable Unit Four (OU4)

Requirement

Citation

Status

Requirement Synopsis

Action to be Taken to Attain Requirement

Massachusetts Clean
Water Act; Supplemental
Requirements for
Hazardous Waste
Management Facilities

M.G.L. ch 21,
§§ 26-53; 314
C.M.R. 8.03

Relevant and Appropriate

This regulation outlines the additional requirements
that must be satisfied in order for a RCRA facility to
comply with the NPDES regulation.

Any discharges from wetland soil/sediment
excavation/ management and excavation
dewatering will be treated to meet these
standards before discharge to surface waters.

Massachusetts Ambient Air
Quality Standards

310 C.M.R.
6.00

Applicable

Sets primary and secondary standards for
emissions of certain contaminants, including
particulate matter.

Emission standards, including for dust, will be
achieved during sediment excavation/
management and water treatment..

Massachusetts Air Pollution
Control Regulations

310 C.M.R.
7.00

Applicable

These regulations set emission limits necessary to
attain ambient air quality standards.

Emission standards, including for dust, will be
achieved during sediment excavation/
management and water treatment..

Massachusetts Water
Quality Standards
Implementation Policy for
the Control of Toxic
Pollutants in Surface
Waters

Feb. 1999

To Be Considered

Guidance on controlling toxic pollutant discharges
to surface waters

This guidance will be used in the establishment of
monitoring standards for surface waters and
sediments, if required for the remedial action.

Allowable Sound

Air Quality
Control Policy
#90-001

To Be Considered

Guidance on sound emissions.

To be used to assess whether any remedial
measures exceed State noise guidance levels.

Erosion and Sediment
Control Guidance



To Be Considered

Guidance on preventing erosion and sedimentation.

Remedial actions will be managed to control
erosion and sedimentation.

5

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Appendix E: TSCA Determination

-------
TSCA 40 CFR SECTION 761.61(c) RISK-BASED DISPOSAL APPROVAL
DETERMINATION

This Determination is included in EPA's Record of Decision ("ROD") to address cleanup of soil and
wetland sediment/soil contamination at the Southwest Properties ("SWP") Operable Unit 4 ("OU4") of
the Wells G&H Superfund Site in Woburn, Massachusetts. EPA has determined that PCB-contaminated
upland soils, wetland sediments/soils, and non-aqueous phase liquid ("NAPL") at concentrations of 1 part
per million ("ppm") or greater total PCBs meet the definition of a PCB remediation waste as defined
under 40 CFR § 761.3. Therefore, these PCB-contaminated soils, wetland sediments/soils, and NAPL are
regulated for cleanup and disposal under 40 CFR Part 761. Under 40 CFR Section 761.61(c), EPA may
authorize disposal of PCBs in a manner not otherwise specified provided EPA determines that the
disposal will not pose an unreasonable risk of injury to health or the environment.

PCBs present on SWP OU4 will be addressed as follows:

Upland soils in the designated "Murphy Waste Oil" and "Whitney Barrel" parcels with greater
than or equal to (">") 50 ppm PCBs will be excavated and disposed off-site as part of an over-all
excavation/capping remedy for upland soils. Any remaining upland soils with less than ("<") 50 ppm
PCBs and equal to or greater than a recreational risk-based level of 5.3 ppm PCBs on OU4 will be capped
with an impermeable cap. That area, and any remaining PCB-contaminated upland soil exceeding 1 ppm
PCBs will be subject to institutional controls restricting residential, school, or daycare use consistent with
TSCA.

As part of an excavation/off-site disposal component of the remedy for wetlands (designated as
the "Murphy Wetlands"), PCB-contaminated wetland soil with >1.3 ppm PCBs and PCB contaminated
wetland sediment with >1.9 ppm PCBs, will also be excavated and disposed off-site, as necessary, to
meet EPA human health and ecological risk-based cleanup standards.

As part of a NAPL excavation/off-site disposal component of the remedy, any PCB-contaminated
NAPL/soil identified through in situ testing will be excavated and disposed of at an off-site disposal
facility licensed to accept the PCB-contaminated waste.

As part of a pump and treat remedy for OU4 groundwater, water will be treated to meet the
TSCA PCB surface water discharge level of 0.5 parts per billion ("ppb") PCBs, prior to discharge to the
Abeijona River or appropriate approved publicly-owned treatment works (POTW), or disposal at an
appropriate off-site permitted disposal facility. Filters or other media generated from the treatment
process will be disposed of at an off-site disposal facility licensed to accept the PCB-contaminated waste.

The proposed PCB cleanup standards are based on EPA human health and ecological risk assessments
that have determined that soil and wetland soil/sediment below these levels will not pose an unreasonable
risk to health or the environment. EPA's Administrative Record, available for public review, includes
information on the nature of the contamination, location and extent of the contamination, the procedures
used relative to sampling, Human Health and Ecological Risk Assessments, and the Proposed Plan for the
SWP OU4.

Consistent with 40 CFR Section 761.61(c) of the Toxic Substances Control Act ("TSCA"), I have
determined that the implementation of the remedial components of the OU4 cleanup that includes: a)
excavation and off-site disposal of upland soils > 50 ppm PCBs, wetland soils >1.3 ppm PCBs, wetland
sediments >1.9 ppm PCBs, and PCB-contaminated NAPL; b) disposal under an impermeable cap of
PCB-contaminated upland soil between 5.3 and < 50 ppm PCBs; c) institutional controls to restrict

1

-------
residential, school, or daycare use for upland soils greater than 1 ppm PCBs; and d) treatment of
groundwater to meet the TSCA PCB discharge standard of 0.5 ppb PCBs to be discharged to a nearby
surface water body (e.g., Abeijona River) or appropriate off-site disposal at permitted facility, or
appropriate approved POTW; and off-site disposal of PCB- contaminated treatment residuals, as
described, will not pose an unreasonable risk of injury to health or the environment as long as the
following conditions are met:

1.	The selected contractor for the PCB remediation work shall submit a contractor work plan
describing the containment and air monitoring that will be employed during PCB remedial activities,
including but not limited to site control, excavation, handling, storage, and disposal activities. This work
plan should also include information on how and where all PCB remediation waste will be
accumulated/stored prior to off-site shipment/disposal and how the PCB remediation waste will be
disposed of; how storm water controls and runoff will be managed; how dust levels will be controlled
and monitored; and how field equipment will be decontaminated.

2.	Soil in the "Northern Whitney Soil Area" contains soils with concentrations of PCB higher than
other areas (by 10 to 100 times) attributable to the former drum storage and washing operations area and
former floor drain line on both the Whitney Property and Abeijona Property. Excavation of soils in the
Northern Whitney Soil Area will include all soils with total PCBs >50 parts per million (ppm) and soils
with residual Non-Aqueous Phase Liquid (NAPL). Excavation is assumed to include excavation of soils
below the water table. Water removed from the excavations will be tested and treated if necessary to meet
the TSCA discharge standard of 0.5 ppb PCBs to be discharged to a nearby surface water body (e.g.,
Abeijona River) or appropriate off-site disposal at a permitted facility, or appropriate approved POTW. In
areas where soil with total PCBs > 50 ppm extend into the water table, the saturated soils will be
excavated to approximately 15 feet in depth. Excavated soils will be moved to a stockpile area for
dewatering and stabilization to facilitate transport to the disposal facility. Any free water generated from
the dewatering process will be tested and treated if necessary to meet the TSCA discharge standard of 0.5
ppb PCBs to be discharged to a nearby surface water body (e.g., Abeijona River) or appropriate off-site
disposal at a permitted facility, or appropriate approved POTW. Additional amendments, if required,
may be added to dewatered soil, as necessary for off-site disposal. Prior to off-site disposal, the soil
stockpiles will be covered to prevent storm water impacts. Direct loading of excavated soils into trucks
for off-site disposal is also possible if the soil has been pre-characterized and is sufficiently dry. The area
will be backfilled and compacted to pre-excavation elevations using clean fill and an amendment mixed
into soil below the water table to reduce/destroy VOC contamination in soil which will also result in
reduction of PCB mobility. All PCB-contaminated soils with > 50 ppm will be excavated and disposed
off-site at a TSCA-approved disposal facility or a RCRA hazardous waste landfill in accordance with 40
CFR § 761.61(a)(5)(i)(B)(2)(///). Confirmatory sampling will be conducted in accordance with 40 CFR
Part 761, Subpart O to document that all PCBs with >50 ppm have been removed and to support that
PCB concentrations are < 50 ppm for off-site disposal if additional soil removal is required.

3.	NAPL-related PCB impacts at two other locations on the Murphy Property contain significantly
impacted soils (e.g., total PCBs > 50 ppm) from former waste oil management operations. The excavations
will proceed approximately 5 to 6 feet into the water table to a total depth of approximately 12 feet below
grade. Sidewall excavation delineation from pre-design and post-excavation bottom samples will be
collected and tested to confirm that the NAPL is completely removed, to the extent practicable. Water
removed from the excavations will be tested and treated if necessary to meet the TSCA discharge standard
of 0.5 ppb PCBs to be discharged to a nearby surface water body (e.g., Abeijona River) or appropriate off-
site disposal at a permitted facility, or appropriate approved POTW. A survey will be conducted to
document the final excavation depth and in each area sampling will be conducted per 40 CFR Part 761,
Subpart O to document that all soils with PCBs > 50 ppm have been removed. Excavated soils will be
moved to a stockpile area for dewatering and stabilization, if necessary, to facilitate transport to the disposal

2

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facility. Any free water generated from the dewatering process will be tested and treated if necessary to
meet TSCA discharge standard of 0.5 ppb PCBs to be discharged to a nearby surface water body (e.g.,
Abeijona River) or appropriate off-site disposal at a permitted facility, or appropriate approved POTW.
Additional amendments, if required, may be added to dewatered soil/NAPL, as necessary for off-site
disposal. Prior to off-site disposal, the soil stockpiles will be covered to prevent storm water impacts. Direct
loading of excavated soils into trucks for off-site disposal is also possible if the soil has been pre-
characterized (via in situ sampling) and is sufficiently dry. The area will be backfilled and compacted to
pre-excavation elevations using clean fill and an amendment mixed in to soil belowthe water table. These
NAPL-related PCB-contaminated soils at the Murphy property with >50 ppm shall be excavated and
disposed off-site at a TSCA-approved disposal facility or a RCRA hazardous waste landfill in accordance
with 40 CFR § 761.61(a)(5)(i)(B)f2)(//7).

4.	Remaining PCB remediation waste in upland soils at the SWP that exceed proposed risk-based
cleanup levels will be under a protective cap consisting of a uniform placement of concrete, engineered
asphalt/bituminous concrete, engineered impermeable cap, or similar material of minimum thickness
spread over the area where PCB remediation waste has been left in place in order to prevent/minimize
human exposure and reduce ecological impacts, to prevent/minimize infiltration of water, and to
prevent/minimize erosion per 40 CFR § 761.61(a)(7). Institutional Controls will be used to protect the
integrity of the protective caps. PCB-contaminated soils that need to be excavated as part of the cap
construction to provide no net flood storage loss will be moved to a stockpile area, dewatered, and
stabilized to facilitate transport to a disposal facility. Water removed from the excavations or from soil
dewatering will be tested and treated if necessary to meet the TSCA discharge standard of 0.5 ppb PCBs
to be discharged to a nearby surface water body (e.g., Abeijona River) or appropriate off-site disposal at
a permitted facility, or appropriate approved POTW. Additional amendments, if required, may be added
to dewatered soil/NAPL, as necessary for off-site disposal. Prior to off-site disposal, the soil stockpiles
will be covered to prevent storm water impacts. Direct loading of excavated soils into trucks for off-site
disposal is also possible if the soil has been pre-characterized and is sufficiently dry. PCB-contaminated
soils shall be disposed off-site at a TSCA-approved disposal facility or a RCRA hazardous waste landfill
in accordance with 40 CFR § 761.61(a)(5)(i)(B)(2)(//7). Alternatively, PCB-contaminated soils may be
disposed at a state-permitted landfill in accordance with 40 CFR § 761.61(a)(5)(i)(B)(2)(/7) provided in
situ (prior to excavation) sampling confirms PCB concentrations are < 50 ppm. Confirmatory sampling
will not be required where remaining PCB-contaminated soil will be under the protective cap.

5.	All PCB-contaminated upland soils exceeding 1 ppm total PCBs shall be subject to institutional
controls restricting residential, school, and daycare use.

6.	For the wetland area, the lower of the applicable human health and ecological proposed cleanup
levels will be applied for the remedial actions (i.e., 1.9 ppm total PCBs for wetland sediment and 1.3
ppm total PCBs for wetland soil). All wetland sediment/soil with PCB concentrations at or above these
proposed cleanup levels will be excavated and disposed off-site at a TSCA-approved disposal facility or
a RCRA hazardous waste landfill in accordance with 40 CFR § 761.61(a)(5)(i)(B)(2)(/77). Water removed
from the excavations or from soil/sediment dewatering will be tested and treated if necessary to meet the
discharge standard of 0.5 ppb PCBs to be discharged to a nearby surface water body (e.g., Abeijona
River) or appropriate off-site disposal at a permitted facility, or appropriate approved POTW. Additional
amendments, if required, may be added to dewatered soil/NAPL, as necessary for off-site disposal. Prior
to off-site disposal, the soil/sediment stockpiles will be covered to prevent storm water impacts. Direct
loading of excavated soil/sediment into trucks for off-site disposal is also possible if the soil/sediment
has been pre-characterized and is sufficiently dry. Confirmatory sampling will be performed to
demonstrate that all wetland sediment/soil with PCB concentrations exceeding the proposed cleanup
levels have been excavated. PCB- contaminated soil/sediment shall be disposed off-site at a TSCA-
approved disposal facility or a RCRA hazardous waste landfill in accordance with 40 CFR §
761.61(a)(5)(i)(B)(2)(/77). Alternatively, PCB- contaminated soil/sediment may be disposed at a state-

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permitted landfill in accordance with 40 C'R § 761.61 
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Appendix F: Acronyms and Abbreviations

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ROD LIST OF ACRONYMS & ABBREVIATIONS



AOC

Administrative Orders by Consent





AOI

Areas of Interest





ARAR

Applicable or Relevant and Appropriate Requirement





AST

Aboveground Storage Tank





B&M

Boston and Maine





BAFs

Bioaccumulation Factors





Beatrice

Beatrice Company





BRA

Baseline Risk Assessment





BSAFs

Biota-Sediment Accumulation Factors





CERCLA

Comprehensive Environmental Response, Compensation, and Liability Act





CFR

Code of Federal Regulations





CHES

Clean Harbors Environmental Services





COCs

Chemicals of Concern





COECs

Contaminants of Ecological Concern





COPECs

Chemicals of Potential Ecological Concern





CO PCs

Chemicals of Potential Concern





CSGWPP

Comprehensive State Groundwater Protection Program





CTE

Central Tendency Exposures





CWA

Clean Water Act





DCE

Dichloroethene





EDI

Estimated Daily Intake





EPA

United States Environmental Protection Agency





EPC

Exposure Point Concentration





ERA

Ecological Risk Assessment





ESD

Explanation of Significant Difference





FEMA

Federal Emergency Management Agency





FIT

Field Investigation Team





FS

Feasibility Study





FYR

Five-Year Review





GW-

Groundwater - Southwest Properties





HEAST

Health Effects Assessment Summary Table





HHRA

Human Health Risk Assessment





HI

Hazard Index





HQ

Hazard Quotient





HVAC

Heating, Ventilating, and Air Conditioning





ICs

Institutional Controls





IEUBK

Integrated Exposure Uptake Biokinetic





l-G

Industrial General





ILCR

Incremental Lifetime Cancer Risk





l-P

Industrial Park





IRA

Immediate Response Action





IRIS

Integrated Risk Information System





ISCO

In Situ Chemical Oxidation





kg

Kilogram





LEDPA

Least Environmentally Damaging Practicable Alternatives



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MANHESP

Massachusetts Heritage & Endangered Species Program





MassDEP

Massachusetts Department of Environmental Protection





MCL

Maximum Contamination Levels





MCP

Massachusetts Contingency Plan





MDC

Metropolitan District Commission





MM

Management of Migration





MNA

Monitored Natural Attenuation





MNR

Monitored Natural Recovery





MOA

Memorandum of Agreement, or Mode of Action





mg

Milligram





MSGRP

Multiple Source Groundwater Response Plan





MWRA

Massachusetts Water Resources Authority





N-

NAPL





NAPL

Non-Aqueous Phase Liquid





NCP

National Oil and Hazardous Substances Pollution Contingency Plan





NPL

National Priorities List





O&M

Operation and Maintenance





OSRR

Office of Site Remediatin and Restoration





OSWER

Office of Solid Waste and Emergency Response





OU

Operable Unit





PAH

Polycyclic Aromatic Hydrocarbons





PCBs

Polychlorinated Biphenyls





PCE

Tetrachloroethene





Plan

Proposed Plan





POTW

Publicly Owned Treatment Works





PPb

Parts Per Billion





ppm

Parts Per Million





PPRTV

Provisional Peer Reviewed Toxicity Values





PRG

Preliminary Remediation Goals





PRP

Potentially Responsible Party





RAO

Remedial Action Objectives





RCRA

Resource Conservation and Recovery Act





RfC

Reference Concentration





RfD

Reference Dose





RG

Remediation Goals





Rl

Remedial Investigation





RI/FS

Remedial Investigation and Feasibility Study





RME

Reasonable Maximum Exposure





ROD

Record of Decision





RPM

Remedial Project Manager





RSL

Regional Screening Levels





SA-

Soil - Aberjona Property





SC

Source Control





SDWA

Safe Drinking Water Act





SM-

Soil - Murphy Property





SOW

Statement of Work





SQO

Sample Quantitation Limits



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svoc

Semi-Volatile Organic Compounds

sw-

Soil - Whitney Property

SWP

Southwest Properties

TBC

To be considered

TCE

Trichloroethene

TSDF

Treatment, Storage & Disposal Facility

TRV

Toxicity Reference Values

TSCA

Toxic Substance Control Act

ug

Microgram

VISL

Vapor Intrusion Screening Levels

VOC

Volatile Organic Compounds

WTL-

Wetland Sediments/Soils - Murphy Wetland

ZVI

Zero-Valent Iron

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Appendix G: Administrative Record Index
and Guidance Documents

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Wells G&H
NPL Site Administrative Record File

Record of Decision (ROD)
Operable Unit (OU) 04 - Southwest

Properties

Index

ROD Dated: September 2017
Released: October 2017

Prepared by
EPA New England
Office of Site Remediation & Restoration

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Introduction to the Collection

This is the administrative record index for the Wells G&H Superfund Site, Woburn,
Massachusetts, Operable Unit (OU) 04 - Southwest Properties Record of Decision (ROD),
released October 2017. The file contains site-specific documents and a list of guidance
documents used by EPA staff in selecting a response action at the site. This file replaces the
administrative record file for Operable Unit (OU) 04 - Southwest Properties Record of Decision
(ROD) Proposed Plan, released July 2017.

This record includes, by reference, the administrative record of the following response actions:
OU 01 Record of Decision (ROD), issued September 14, 1989, and the Industri-Plex OU
02/Wei Is G&H OU3 Record of Decision (ROD), issued January 31, 2006.

Documents listed as bibliographic sources in individual reports might not be listed separately in
the index.

The administrative record file is available for review at:

Online: https://semspub.epa.gov/src/col 1 ection/01 /AR65178

EPA New England

Office of Site Remediation & Restoration

Records and Information Center

5 Post Office Square, Suite 100 (OSRR02-3)

Boston, MA 02109-3912

(by appointment)

617-918-1440 (phone)

617-918-0440 (fax)

Woburn Public Library
45 Pleasant Street
Woburn, MA 01801
781-933-0148 (phone)
http://woburnpubliclibrary.org

Additional information about the site is also available at www.epa.gov/superfund/wellsgh

An administrative record file is required by the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act (SARA).

Questions about this administrative record file should be directed to the EPA New England site
manager, Joe LeMay (617) 918-1323.

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 01.02 - PRELIMINARY ASSESSMENT

Page 1 of 62

485985 PRELIMINARY SITE ASSESSMENT (PA), MURPHY'S WASTE OIL SERVICE, INC.

Author: , CLEAN HARBORS ENVIRONMENTAL
ENGINEERING CORP

Addressee: ; CLEAN HARBORS INC

# of Pages: 47
Doc Date: 01/01/1989
Resource Type:

Report

Access Control:

Uncontrolled

530334 ENVIRONMENTAL SITE ASSESSMENT FINAL REPORT - 228 SALEM STREET [INCOMPLETE]

Author: , 21E INC

Addressee: JOHN J RILEY JR, NONE

# of Pages: 88
Doc Date: 12/26/1990
Resource Type:

Report

Access Control:

Uncontrolled

530335 ENVIRONMENTAL SITE ASSESSMENT FINAL REPORT - 228 SALEM STREET

Author: , 21E INC

Addressee: MAGGIORE COMPANIES

# of Pages: 107
Doc Date: 08/10/1993
Resource Type:

Report

Access Control:

Uncontrolled

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 01.03 - SITE INSPECTION/INVESTIGATION

Page 2 of 62

485980 SITE INSPECTION (SI) REPORT FOR THE WHITNEY BARREL COMPANY SITE

Author: , ECOLOGY & ENVIRONMENT INC

Addressee: ; US EPA REGION 1

# of Pages: 47
Doc Date: 12/16/1980
Resource Type:

Report

Access Control:

Uncontrolled

485981 SITE INSPECTION (SI) REPORT FOR ABERJONA AUTO PARTS

Author: , ECOLOGY & ENVIRONMENT INC

Addressee: US EPA REGION 1

# of Pages: 29
Doc Date: 11/26/1980
Resource Type:

Report

Access Control:

Uncontrolled

485982 UPDATE TO SITE INSPECTION (SI) REPORT FOR ABERJONA AUTO PARTS (TRANSMITTAL MEMO ATTACHED)

Author: LI YANG CHU, NUS CORP

Addressee: DONALD SMITH, US EPA REGION 1

# of Pages: 10
Doc Date: 09/19/1985
Resource Type:

Report

Access Control:

Uncontrolled

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

Page 3 of 62

File Break: 01.03 - SITE INSPECTION/INVESTIGATION

547753 FINAL SITE INSPECTION (SI) PRIORITIZATION REPORT FOR JOHN J. RILEY

Author: , ROY F WESTON INC

Addressee: ; US EPA REGION 1

# of Pages: 33
Doc Date: 09/25/1998
Resource Type:

Report

Access Control:

Uncontrolled

File Break: 01.18 - SITE ASSESSMENT SUPPORT DOCUMENTATION

248054 FIELD INVESTIGATIONS OF UNCONTROLLED HAZARDOUS WASTE SITES, EVALUATION OF THE HYDROGEOLOGY AND

GROUNDWATER QUALITY OF EAST AND NORTH WOBURN, MA, VOLUME 3 OF 4, APPENDIX C: WELL DATA- FINAL REPORT

Author: , ECOLOGY AND ENVIRONMENT INC

# of Pages: 187
Doc Date: 06/25/1982
Resource Type:

Addressee: JOHN F HACKLER, US EPA REGION 1 - OFFICE OF UNCONTROLI Report
WASTE SITES

Access Control:

Uncontrolled

248055 FIELD INVESTIGATIONS OF UNCONTROLLED HAZARDOUS WASTE SITES, EVALUATION OF THE HYDROGEOLOGY AND
GROUNDWATER QUALITY OF EAST AND NORTH WOBURN, MA, VOLUME 1 OF 4 - FINAL REPORT [MARGINALIA]

Author: , ECOLOGY & ENVIRONMENT INC

# of Pages: 81
Doc Date: 06/25/1982
Resource Type:

Addressee: JOHN F HACKLER, US EPA REGION 1 - OFFICE OF UNCONTROLI Report
WASTE SITES

Access Control:

Uncontrolled

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 01.18 - SITE ASSESSMENT SUPPORT DOCUMENTATION

Page 4 of 62

248056 FIELD INVESTIGATIONS OF UNCONTROLLED HAZARDOUS WASTE SITES, EVALUATION OF THE HYDROGEOLOGY AND	# 0f Pages: 306

GROUNDWATER QUALITY OF EAST AND NORTH WOBURN, MA, VOLUME 4 OF 4 - APPENDIX G : ANALYTICAL DATA, FINAL REPORgoc Date. 06/25/1982

Resource Type:

Author: , ECOLOGY AND ENVIRONMENT INC	Addressee: JOHN F HACKLER, US EPA REGION 1 - OFFICE OF UNCONTROLI Report

WASTE SITES

Access Control:

Uncontrolled

248057 FIELD INVESTIGATIONS OF UNCONTROLLED HAZARDOUS WASTE SITES, CHLORINATED SOLVENT CONTAMINATION OF THE
GROUNDWATER, FINAL REPORT

Author: , ECOLOGY & ENVIRONMENT INC

# of Pages: 125
Doc Date: 03/08/1982
Resource Type:

Addressee: JOHN F HACKLER, US EPA REGION 1 - OFFICE OF UNCONTROLI Report

WASTE SITES

Access Control:

Uncontrolled

563826 FIELD INVESTIGATION OF UNCONTROLLED HAZARDOUS WASTE SITES, EVALUATION OF THE HYDROGEOLOGY AND

GROUNDWATER QUALITY OF EAST AND NORTH WOBURN, MASSACHUSETTS - VOLUME 2 OF 4, APPENDICES A, B, D, E AND F

Author: , ECOLOGY & ENVIRONMENT INC

Addressee: JOHN HACKLER, US EPA REGION 1

# of Pages: 142
Doc Date: 06/25/1982
Resource Type:

Report

Access Control:

Uncontrolled

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 02.02 - REMOVAL RESPONSE REPORTS

Page 5 of 62

284065 CORRECTIVE ACTION INVESTIGATION REPORT, MURPHY'S WASTE OIL SERVICE INC, VOL 1 OF 3

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee:

# of Pages: 122
Doc Date: 04/15/1996
Resource Type:

Report

Access Control:

Uncontrolled

284066 CORRECTIVE ACTION INVESTIGATION REPORT, MURPHY'S WASTE OIL SERVICE INC, VOL 2 OF 3

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee:

# of Pages: 842
Doc Date: 04/15/1996
Resource Type:

Report

Access Control:

Uncontrolled

448681 GROUNDWATER MONITORING PLAN: VOLUME 1 OF 2 (WITH 04/15/2002 LETTER OF TRANSMITTAL)

Author: , CLEAN HARBORS

Addressee: MURPHYS WASTE OIL SERVICE INC

# of Pages: 149
Doc Date: 04/08/2002
Resource Type:

Report

Access Control:

Uncontrolled

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 02.02 - REMOVAL RESPONSE REPORTS

Page 6 of 62

448682 GROUNDWATER MONITORING PLAN: VOLUME 2 OF 2

Author: , CLEAN HARBORS

Addressee: ; MURPHYS WASTE OIL SERVICE INC

# of Pages: 825
Doc Date: 04/08/2002
Resource Type:

Report

Access Control:

Uncontrolled

448684 CORRECTIVE ACTION INVESTIGATION REPORT PART 2, MURPHY'S WASTE OIL SERVICE INC, VOLUME 1 OF 1

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: MURPHYS WASTE OIL SERVICE INC

# of Pages: 338
Doc Date: 03/16/1998
Resource Type:

Report

Access Control:

Uncontrolled

448685 CORRECTIVE ACTION INVESTIGATION REPORT, MURPHY'S WASTE OIL SERVICE INC, VOLUME 3 OF 3

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee:

# of Pages: 307
Doc Date: 04/15/1996
Resource Type:

Report

Access Control:

Uncontrolled

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 02.02 - REMOVAL RESPONSE REPORTS

Page 7 of 62

448686 ADDENDUM TO CORRECTIVE ACTION INVESTIGATION REPORT PART 2, MURPHY'S WASTE OIL SERVICE INC

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: ; MURPHYS WASTE OIL SERVICE INC

# of Pages: 58
Doc Date: 12/11/1998
Resource Type:

Report

Access Control:

Uncontrolled

448697 IMMEDIATE RESPONSE ACTION PLAN (IRAP) FOR MURPHY'S OIL WASTE SERVICE, INC (05/08/2009 TRANSMITTAL LETTER
ATTACHED)

Author: , CLEAN HARBOR ENVIRONMENTAL

Addressee: MURPHYS WASTE OIL SERVICES INC

# of Pages: 67
Doc Date: 11/22/2002
Resource Type:

Report

Access Control:

Uncontrolled

457913 IMMEDIATE RESPONSE ACTION STATUS REPORT AND PLAN MODIFICATION FOR MURPHY'S OIL WASTE SERVICE, INC

Author: , CLEAN HARBOR ENVIRONMENTAL

Addressee: MURPHYS WASTE OIL SERVICE INC

# of Pages: 199
Doc Date: 08/21/2003
Resource Type:

Report

Access Control:

Uncontrolled

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WELLS G&H	Page 8 of 62

AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 02.02 - REMOVAL RESPONSE REPORTS

462023

Author:

REMOVAL PROGRAM PRELIMINARY ASSESSMENT/SITE INVESTIGATION (PA/SI) REPORT FOR THE JOHN J. RILEY SITE, WOBURN # 0f Pages: 47
MA

, US EPA REGION 1 EMERGENCY PLANNING
AND RESPONSE BRANCH

Addressee:

Doc Date: 02/01/2006
Resource Type:

Report

Access Control:

Uncontrolled

485989 REMOVAL PROGRAM PRELIMINARY ASSESSMENT/SITE INVESTIGATION (PA/SI) REPORT FOR THE MURPHY PROPERTY (263
SALEM STREET) SITE

Author: , WESTON SOLUTIONS INC

Addressee: US EPA REGION 1

# of Pages: 74
Doc Date: 11/01/2006
Resource Type:

Report

Access Control:

Uncontrolled

599277 IMMEDIATE RESPONSE ACTION (IRA) STATUS REPORT, MURPHY'S WASTE OIL SERVICE, INC., 252 SALEM STREET

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: MURPHYS WASTE OIL SERVICE INC

# of Pages: 32
Doc Date: 01/29/2016
Resource Type:

Report

Access Control:

Uncontrolled

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 02.02 - REMOVAL RESPONSE REPORTS

Page 9 of 62

599279 IMMEDIATE RESPONSE ACTION (IRA) STATUS REPORT, MURPHY'S WASTE OIL SERVICE, INC., 252 SALEM STREET

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: ; MURPHYS WASTE OIL SERVICE INC

# of Pages: 31
Doc Date: 01/17/2017
Resource Type:

Report

Access Control:

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599280 IMMEDIATE RESPONSE ACTION (IRA) STATUS REPORT, MURPHY'S WASTE OIL SERVICE, INC., 252 SALEM STREET (TRANSMITTAL # 0f Pages: 32

LETTER ATTACHED)	Doc Date: 01/21/2014

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: MURPHYS WASTE OIL SERVICE INC

Resource Type:

Report

Access Control:

Uncontrolled

599283 IMMEDIATE RESPONSE ACTION (IRA) STATUS REPORT, MURPHY'S WASTE OIL SERVICE, INC., 252 SALEM STREET

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: MURPHYS WASTE OIL SERVICE INC

# of Pages: 29
Doc Date: 07/13/2015
Resource Type:

Report

Access Control:

Uncontrolled

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 02.03 - SAMPLING & ANALYSIS DATA (REMOVAL RESPONSE)

Page 10 of 62

455166 ADDENDUM 1 TO HYDROGEOLOGIC CHARACTERIZATION REPORT, VOL 1 OF 2 (INCLUDES TRANSMITTAL LETTER)

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: ; MURPHYS WASTE OIL SERVICES INC

# of Pages: 89
Doc Date: 01/31/1995
Resource Type:

Report

Access Control:

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455167 ADDENDUM 1 TO HYDROGEOLOGIC CHARACTERIZATION REPORT, VOL 2 OF 2

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: MURPHYS WASTE OIL SERVICES INC

# of Pages: 277
Doc Date: 01/31/1995
Resource Type:

Report

Access Control:

Uncontrolled

455168 HYDROGEOLOGIC CHARACTERIZATION REPORT, VOL 1 OF 2

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: MURPHYS WASTE OIL SERVICES INC

# of Pages: 57
Doc Date: 02/01/1994
Resource Type:

Report

Access Control:

Uncontrolled

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WELLS G&H
AR Collection: 65178
Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

File Break: 02.03 - SAMPLING & ANALYSIS DATA (REMOVAL RESPONSE)

Page 11 of 62

455169 HYDROGEOLOGIC CHARACTERIZATION REPORT, VOL 2 OF 2 [MARGINALIA]

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: ; MURPHYS WASTE OIL SERVICES INC

# of Pages: 398
Doc Date: 02/01/1994
Resource Type:

Report

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549963 POLLUTION REPORT (POLREP) NO. 3, FINAL - JOHN J. RILEY SITE - MOBILIZATION DATE 08/01/2006

Author: , US EPA REGION 1

Addressee:

# of Pages: 2
Doc Date: 11/15/2006
Resource Type:

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File Break: 02.09 - ACTION MEMORANDA

463008 REQUEST FOR A REMOVAL ACTION AT THE JOHN J RILEY SITE, WOBURN, MIDDLESEX COUNTY, MASSACHUSETTS	# 0f Pages: 9

Doc Date: 06/15/2006
Resource Type:

Author: FRANK GARDNER, US EPA REGION 1	Addressee: SUSAN STUDLIEN, US EPA REGION 1	Memorandum

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485988

LETTER REGARDING REFERRAL OF MURPHY'S WASTE OIL SERVICE FROM RCRA TO CERCLA

Author: SUSAN STUDLIEN, US EPA REGION 1 - OFFICE
OF SITE REMEDIATION & RESTORATION

Addressee: WILLIAM CONNORS, CLEAN HARBORS OF BRAINTREE INC

# of Pages: 2
Doc Date: 08/23/2004
Resource Type:

Letter

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485990

EXPANDED TRIP REPORT FOR JOHN J. RILEY

Author: , WESTON SOLUTIONS INC

Addressee: US EPA REGION 1

# of Pages: 66
Doc Date: 09/21/2004
Resource Type:

Report

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587706 REDACTED RESPONSE TO REQUEST FOR DOCUMENTS REGARDING ABERJONA AUTO PARTS PROPERTY OIL-WATER SEPARATOR # 0f Pages: 7

AND UNDERGROUND STORAGE TANK (UST) REMOVAL	Doc Date. 09/03/2009

Resource Type:

Author: ROBERT HOLLAND, NORTH BILLERICA (MA)	Addressee: JOSEPH LEMAY, US EPA REGION 1	Letter

RESIDENT

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596279 EPA COMMENTS ON FEBRUARY 2015 DRAFT REMEDIAL INVESTIGATION (RI) REPORT BY AECOM

Author: JOSEPH F LEMAY, US EPA REGION 1

Addressee: PETER S COX, AECOM

# of Pages: 293
Doc Date: 03/09/2016
Resource Type:

Report

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596293 MAP: TAX MAP 37, WOBURN, MA

Author: , WOBURN (MA) CITY OF

Addressee:

# of Pages: 1
Doc Date: 08/01/2014
Resource Type:

Figure/Map/ Drawing

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596294 MAP: TAX MAP 38, WOBURN, MA

Author: , WOBURN (MA) CITY OF

Addressee:

# of Pages: 1
Doc Date: 08/01/2014
Resource Type:

Figure/Map/ Drawing

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622372 LETTER REGARDING CONSTRUCTION OF SMALL RINK - VAPOR BARRIER, 278-280 SALEM STREET

Author: SAMUEL W BUTCHER, GOLDMAN	Addressee: JOSEPH F LEMAY, US EPA REGION 1

ENVIRONMENTAL CONSULTANTS

# of Pages: 10
Doc Date: 05/09/2008
Resource Type:

Letter

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295888 SITE ASSESSMENT REPORT OF THE FORMER WHITNEY BARREL COMPANY SITE BY GHR ENGINEERING, VOLUMES 1 AND 2

Author: , GHR ENGINEERING ASSOCIATES INC

Addressee: ruth WHITNEY, WHITNEY BARREL CO INC

# of Pages: 353
Doc Date: 12/01/1988
Resource Type:

Report

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620710 SAMPLING LOCATIONS AND SAMPLING RESULTS, SOUTHWEST PROPERTIES, 07/31/2013-08/02/2013

Author: , AECOM

Addressee:

# of Pages: 2
Doc Date: 08/02/2013
Resource Type:

Analytical Data Document

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620711 REVISED WORK PLAN FOR INSTALLATION OF MONITORING WELLS AND MONITORED NATURAL ATTENUATION GROUNDWATER # 0f Pages: 181
SAMPLING, SOUTHWEST PROPERTIES	Doc Date; 06/ll/2013

Resource Type:

Author: PETER S COX, AECOM	Addressee: JOSEPH LEMAY, US EPA REGION 1	Work Plan

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File Break: 03.04 - INTERIM DELIVERABLES (RI)

446073 IMMEDIATE RESPONSE ACTION STATUS REPORT, MURPHY'S WASTE OIL SERVICE INC (WITH 02/29/2008 TRANSMITTAL LETTER) # 0f Pages: 31

Doc Date: 02/22/2008
Resource Type:

Author: , CLEAN HARBORS ENVIRONMENTAL	Addressee: ; MURPHYS WASTE OIL SERVICES INC	Report

SERVICES INC

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446074 IMMEDIATE RESPONSE ACTION STATUS REPORT, MURPHY'S WASTE OIL SERVICE INC (WITH 01/29/2007 TRANSMITTAL LETTER) # 0f Pages: 51

Doc Date: 12/22/2006
Resource Type:

Author: , CLEAN HARBORS ENVIRONMENTAL	Addressee: ; MURPHYS WASTE OIL SERVICE INC	Report

SERVICES INC

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446075 IMMEDIATE RESPONSE ACTION STATUS REPORT, MURPHY'S WASTE OIL SERVICE INC

Author: , CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

Addressee: ; MURPHYS WASTE OIL SERVICE INC

# of Pages: 47
Doc Date: 06/22/2006
Resource Type:

Report

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446076 IMMEDIATE RESPONSE ACTION STATUS REPORT, MURPHY'S WASTE OIL SERVICE INC (WITH 01/27/005 TRANSMITTAL LETTER) # 0f Pages: 50

Doc Date: 01/21/2005
Resource Type:

Author: , CLEAN HARBORS ENVIRONMENTAL	Addressee: ; MURPHY WASTE OIL SERVICE INC	Report

SERVICES INC

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File Break: 03.06 - REMEDIAL INVESTIGATION REPORTS

16934 REVIEW OF EPA REMEDIAL INVESTIGATION (RI) REPORT, PART 1, VOLUME 7: APPENDIX D	# of Pages: 23

Doc Date: 07/01/1987
Resource Type:

Author: , GEOTRANS INC	Addressee: . w r GRACE & CO	Report

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65302 CENTRAL AREA REMEDIAL INVESTIGATION (RI), PHASE 1A REPORT, VOLUME 2: FIGURES

Author: , GEOTRANS INC

Addressee: DAVID O LEDERER, US EPA REGION 1

# of Pages: 98
Doc Date: 01/01/1994
Resource Type:

Report

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65306 CENTRAL AREA REMEDIAL INVESTIGATION (RI), PHASE 1A REPORT, VOLUME 3: APPENDICES

Author: , GEOTRANS INC

Addressee: DAVID O LEDERER, US EPA REGION 1

# of Pages: 502
Doc Date: 01/01/1994
Resource Type:

Report

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65307 CENTRAL AREA REMEDIAL INVESTIGATION (RI), PHASE 1A REPORT, VOLUME 4: APPENDIX H

Author: , GEOTRANS INC

Addressee: DAVID O LEDERER, US EPA REGION 1

# of Pages: 505
Doc Date: 01/01/1994
Resource Type:

Report

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65309 CENTRAL AREA REMEDIAL INVESTIGATION (RI), PHASE 1A REPORT, VOLUME 1 (02/18/1994 TRANSMITTAL LETTTER ATTACHED) # 0f Pages: 240

Doc Date: 02/14/1994
Resource Type:

Author: , GEOTRANS INC	Addressee: DAVID O LEDERER, US EPA REGION 1	Report

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230914 GROUNDWATER USE AND VALUE DETERMINATION (06/21/04 TRANSMITTAL LETTER IS ATTACHED)

Author: , MA DEPT OF ENVIRONMENTAL
PROTECTION

Addressee:

# of Pages: 5
Doc Date: 06/01/2004
Resource Type:

Report

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259667

SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES, VOL. 1 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 305
Doc Date: 08/01/2003
Resource Type:

Report

, US EPA REGION 1

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259668 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 2 OF 23

Author: , RETEC GROUP, THE

Addressee: ; BEATRICE COMPANY

# of Pages: 340
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259670 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 4 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1279
Doc Date: 08/01/2003
Resource Type:

Report

, US EPA REGION 1

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259671 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 5 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1233
Doc Date: 08/01/2003
Resource Type:

Report

, US EPA REGION 1

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259672 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 6 OF 23

Author: , RETEC GROUP, THE

Addressee: ; BEATRICE COMPANY

# of Pages: 1191
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259673 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 7 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1333
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259674 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 8 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1284
Doc Date: 08/01/2003
Resource Type:

Report

, US EPA REGION 1

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259675 SUPPLEMENTAL REMEDIAL INVESTIGATION REPORT (RI) SOUTHWEST PROPERTIES VOL. 9 OF 23

Author: , RETEC GROUP, THE

Addressee: ; BEATRICE COMPANY

# of Pages: 1244
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259676 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 10 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1264
Doc Date: 08/01/2003
Resource Type:

Report

, US EPA REGION 1

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259677 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 11 OF 23 [BEST AVAILABLE COPY]

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1327
Doc Date: 08/01/2003
Resource Type:

Report

, US EPA REGION 1

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259678

SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 12 OF 23

Author: , RETEC GROUP, THE

Addressee: ; BEATRICE COMPANY

# of Pages: 1431
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259679 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 13 OF 23 [BEST AVAILABLE COPY]

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1379
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259680

SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 14 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1296
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259681 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 15 OF 23

Author: , RETEC GROUP, THE

Addressee: ; BEATRICE COMPANY

# of Pages: 1251
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259682 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 16 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1270
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259683 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 17 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1267
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259684 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 18 OF 23

Author: , RETEC GROUP, THE

Addressee: ; BEATRICE COMPANY

# of Pages: 1279
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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259685 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 3 OF 23 [PART 2 OF 2]

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 494
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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260703 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES, VOL. 19 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1271
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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260704 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES, VOL. 20 OF 23

Author: , RETEC GROUP, THE

Addressee: ; BEATRICE COMPANY

# of Pages: 1393
Doc Date: 08/01/2003
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, US EPA REGION 1

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260705 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES, VOL. 21 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1356
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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260706 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES, VOL. 22 OF 23

Author: , RETEC GROUP, THE

Addressee: BEATRICE COMPANY

# of Pages: 1358
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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260707 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES, VOL. 23 OF 23

Author: , RETEC GROUP, THE

Addressee: ; BEATRICE COMPANY

# of Pages: 955
Doc Date: 08/01/2003
Resource Type:

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, US EPA REGION 1

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455178 REMEDIAL INVESTIGATION (RI) PHASE 1A REPORT, ATTACHMENT 1, DRAFT RI SOUTHWEST PROPERTIES [MARGINALIA]

Author: , REMEDIATION TECHNOLOGIES INC

Addressee: BEATRICE COMPANY

# of Pages: 430
Doc Date: 02/01/1994
Resource Type:

Report

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549964 [REDACTED] SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) REPORT SOUTHWEST PROPERTIES VOL. 3 OF 23 [PART 1 OF 2]	# 0f Pages: 820

[HANDWRITTEN NOTES]	Doc Date; 08/01/2003

Resource Type:

Author: , RETEC GROUP, THE	Addressee: ; BEATRICE COMPANY	Report

, US EPA REGION 1

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596278 REMEDIAL INVESTIGATION (RI) REPORT

Author: , AECOM TECHNICAL SERVICES INC

Addressee:

# of Pages: 98310
Doc Date: 11/01/2016
Resource Type:

Report

, BEATRICE COMPANY

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596279 EPA COMMENTS ON FEBRUARY 2015 DRAFT REMEDIAL INVESTIGATION (RI) REPORT BY AECOM

Author: JOSEPH F LEMAY, US EPA REGION 1

Addressee: PETER S COX, AECOM

# of Pages: 293
Doc Date: 03/09/2016
Resource Type:

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474222 QUALITY ASSURANCE PROJECT PLAN (QAPP) FOR SUPPLEMENTAL REMEDIAL INVESTIGATION (RI)	# 0f Pages: 822

Doc Date: 11/09/2010
Resource Type:

Author: , AECOM	Addressee: BEATRICE COMPANY	Work Plan

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474223 SUPPLEMENTAL REMEDIAL INVESTIGATION (RI) WORK PLAN (TABLES AND FIGURES ATTACHED)

Author: , AECOM

Addressee: ; SOUTHWEST PROPERTIES

# of Pages: 297
Doc Date: 11/01/2010
Resource Type:

Work Plan

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622371

SOIL AND GROUNDWATER MANAGEMENT PLAN FOR CONSTRUCTION ACTIVITIES AT 280 SALEM STREET

Author: , GOLDMAN ENVIRONMENTAL
CONSULTANTS

Addressee: 280 SALEM STREET LLC

# of Pages: 99
Doc Date: 01/01/2006
Resource Type:

Work Plan

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70383 BASELINE HUMAN HEALTH AND ECOLOGICAL RISK ASSESSMENT, SOUTHWEST PROPERTIES, VOLUME 1 OF 4	# of Pages: 2828

Doc Date: 02/01/2006
Resource Type:

Author: , METCALF & EDDY INC	Addressee:	Report

, TRC ENVIRONMENTAL CORP

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244893 TRANSMITTAL OF REPLACEMENT PAGES FOR MARCH 2004 BASELINE HUMAN HEALTH AND ECOLOGICAL RISK ASSESSMENT,
SOUTHWEST PROPERTIES

Doc Date: 02/09/2006
Resource Type:

Correspondence

# of Pages: 142

Author: JOSEPH F LEMAY, US EPA REGION 1

Addressee: pete COX, RETEC GROUP, THE

ROBERT HOLLAND, NONE

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JOHN KELLEY, NONE

JEFF LAWSON, PROJECT CONTROL COMPANIES INC.

CHARLES J MCCREERY, CLEAN HARBORS ENVIRONMENTAL
SERVICES INC

THOMAS L MCLAUGHLIN, WOBURN (MA) CITY OF - WOBURN C
COUNCIL

JOAN MURPHY, NONE
JOHN E III WHITNEY, NONE
RUTH WHITNEY, NONE
, WOBURN (MA) PUBLIC LIBRARY

448675 EPA COMMENTS ON OPERABLE UNIT (OU) 2 SOUTHWEST PROPERTIES RISK ASSESSMENT (WITH TRANSMITTAL LETTER)

# of Pages: 35

Author: JOSEPH F LEMAY, US EPA REGION 1

Addressee: PETER S COX, AECOM

Doc Date: 05/14/2009
Resource Type:

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457951 BASELINE HUMAN HEALTH AND ECOLOGICAL RISK ASSESSMENT, SOUTHWEST PROPERTIES, VOLUME 2 OF 4: TABLES

Author: , METCALF & EDDY INC

Addressee:

# of Pages: 668
Doc Date: 02/01/2006
Resource Type:

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, TRC ENVIRONMENTAL CORP

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457959 BASELINE HUMAN HEALTH AND ECOLOGICAL RISK ASSESSMENT, SOUTHWEST PROPERTIES, VOLUME 3 OF 4: APPENDIX A
THROUGH APPENDIX C.4 [MARGINALIA]

Author: , METCALF & EDDY INC

Addressee:

# of Pages: 438
Doc Date: 02/01/2006
Resource Type:

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, TRC ENVIRONMENTAL CORP

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457960 BASELINE HUMAN HEALTH AND ECOLOGICAL RISK ASSESSMENT, SOUTHWEST PROPERTIES, VOLUME 4 OF 4: APPENDIX C.4	# 0f Pages: 993

THROUGH APPENDIX D	Doc Date; 02/01/2006

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, TRC ENVIRONMENTAL CORP

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541095 BASELINE HUMAN HEALTH AND ECOLOGICAL RISK ASSESSMENT, SOUTHWEST PROPERTIES, OPERABLE UNIT (OU) 2, VOLUME 1 # 0f Pages: 1724
THROUGH VOLUME 3	Doc Date; 03/01/2014

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Author: , TRC ENVIRONMENTAL CORP	Addressee: ; US EPA REGION 1	Report

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599281 EPA SOUTHWEST PROPERTIES (SWP) SITE VISITS ON 06/23/2009 AND 07/23/2010, WHITNEY BARREL PROPERTY, 256 SALEM STREET, # 0f Pages: 5

WATER OBSERVED UNDER RUSTED SOUTHERN PORTION OF WHITNEY BUILDING AND WOODEN FLOOR / FOUNDATION	Doc Date; 07/23/2010

Resource Type:

Author: , US EPA REGION 1	Addressee:	Photograph

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599282 LETTER REGARDING RESULTS OF COORDINATED MULTI-PARTY PRE-PHASE IB WORK PLAN GROUNDWATER SAMPLING AND
WATER LEVEL MEASUREMENTS, CENTRAL AREA

Author: JAMES R ASH, GEI CONSULTANTS, INC.	Addressee: JOSEPH LEMAY, US EPA REGION 1

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# of Pages: 26
Doc Date: 04/20/2012
Resource Type:

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596281 EPA COMMENTS ON THE 02/2015 DRAFT FEASIBILITY STUDY (FS) BY AECOM

Author: JOSEPH F LEMAY, US EPA REGION 1

Addressee: PETER S COX, AECOM

# of Pages: 430
Doc Date: 03/22/2016
Resource Type:

Letter

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620700 FEASIBILITY STUDY (FS) REPORT ADDEDNDUM (12/01/2016 AECOM FEASIBILITY STUDY (FS) ATTACHED)

Author: , US EPA REGION 1

Addressee:

# of Pages: 1248
Doc Date: 07/01/2017
Resource Type:

Report

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File Break: 04.07 - WORK PLANS & PROGRESS REPORTS (FS)

599284 VAPOR INTRUSION ASSESSMENT WORK PLAN, SOUTHWEST PROPERTIES	# 0f Pages: 75

Doc Date: 03/01/2013
Resource Type:

Author: , AECOM	Addressee: SOUTHWEST PROPERTIES	Work Plan

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599286 LETTER REGARDING REVISED WORK PLAN FOR INSTALLATION OF MONITORING WELLS AND MONITORED NATURAL
ATTENUATION GROUNDWATER SAMPLING, SOUTHWEST PROPERTIES

Author: PETER S COX, AECOM

Addressee:

JOSEPH LEMAY, US EPA REGION 1

# of Pages: 181
Doc Date: 07/01/2013
Resource Type:

Letter

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File Break: 04.09 - PROPOSED PLANS FOR SELECTED REMEDIAL ACTION

599262 PROPOSED PLAN

Author: , US EPA REGION 1

Addressee:

# of Pages: 47
Doc Date: 07/01/2017
Resource Type:

Report

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599270 DRAFT TSCA DETERMINATION, TSCA 40 CFR SECTION 761.61(C) DRAFT RISK-BASED DISPOSAL APPROVAL DETERMINATION

Author: , US EPA REGION 1

Addressee:

# of Pages: 4
Doc Date: 07/14/2017
Resource Type:

Report

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622388 LETTER REGARDING STATE CONCURRENCE WITH RECORD OF DECISION (ROD), SOUTHWEST PROPERTIES

Author: PAUL LOCKE, MA DEPT OF ENVIRONMENTAL	Addressee: BRYAN OLSON, US EPA REGION 1

PROTECTION

# of Pages: 3

Doc Date: 09/28/2017
Resource Type:

Letter

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620755 EMAIL REQUESTING EXTENSION TO COMMENT PERIOD ON PROPOSED PLAN (08/10/2017 EMAIL TRANSMITTAL ATTACHED)

Author: SAMUEL BUTCHER, LOUREIRO ENGINEERING
ASSOCIATES INC

Addressee: JOSEPH F LEMAY, US EPA REGION 1

# of Pages: 0
Doc Date: 08/09/2017
Resource Type:

Email

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620767

PUBLIC COMMENT ON PROPOSED CLEAN UP PLAN FOR THE SOUTH WEST PROPERTIES

Author: MICHAEL RAYMOND, ABERJONA STUDY
COALITION INC

Addressee: JOSEPH LEMAY, US EPA REGION 1

# of Pages: 4
Doc Date: 08/11/2017
Resource Type:

Letter

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620769

PUBLIC COMMENT ON PROPOSED PLAN

Author: JENNIFER MCWEENEY, MA DEPT OF
ENVIRONMENTAL PROTECTION

Addressee: JOSEPH LEMAY, US EPA REGION 1

# of Pages: 3
Doc Date: 08/11/2017
Resource Type:

Letter

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620783 PUBLIC COMMENT ON PROPOSED PLAN

Author: , S&J PROPERTY MANAGEMENT

Addressee: JOSEPH LEMAY, US EPA REGION 1

# of Pages: 1
Doc Date: 08/17/2017
Resource Type:

Memorandum

JENNIFER MCWEENEY, MA DEPT OF ENVIRONMENTAL PROTEi

JIM MURPHY, US EPA REGION 1

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622330 PUBLIC COMMENT ON PROPOSED PLAN WITH RESPECT TO REMEDIATION PROGRAM, SOUTHWEST PROPERTIES

Author: SAMUEL BUTCHER, LOUREIRO ENGINEERING
ASSOCIATES INC

, 280 SALEM STREET LLC

Addressee: JOSEPH LEMAY, US EPA REGION 1

# of Pages: 5
Doc Date: 09/07/2017
Resource Type:

Letter

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622335

PUBLIC COMMENTS ON THE PROPOSED PLAN FOR THE SOUTHWEST PROPERTIES PORTION OF THE SITE

Author: , AECOM

Addressee: ; US EPA REGION 1

# of Pages: 5
Doc Date: 09/12/2017
Resource Type:

Report

, BEATRICE COMPANY

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622387 RESPONSIVENESS SUMMARY, RECORD OF DECISION (ROD), SOUTHWEST PROPERTIES

Author: , US EPA REGION 1

Addressee:

# of Pages: 21
Doc Date: 09/29/2017
Resource Type:

Report

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File Break: 05.04 - RECORD OF DECISION (ROD)

16796 RECORD OF DECISION (ROD)	# 0f Pages: 226

Doc Date: 09/14/1989
Resource Type:

Author: , US EPA REGION 1	Addressee:	Report

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622386 RECORD OF DECISION (ROD), SOUTHWEST PROPERTIES

Author: , US EPA REGION 1	Addressee:

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# of Pages: 320
Doc Date: 09/29/2017
Resource Type:

Report

File Break: 06.06 - WORK PLANS & PROGRESS REPORTS (RD)

599263 DRAFT BEDROCK INVESTIGATION WORK PLAN, WILDWOOD PROPERTY [MARGINALIA]	# 0f Pages: 66

Doc Date: 08/04/1993
Resource Type:

Author: , REMEDIATION TECHNOLOGIES INC	Addressee: BEATRICE COMPANY	Work Plan

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File Break: 07.05 - REMEDIAL ACTION DOCUMENTS

553621 REMEDIAL ACTION (RA) COMPLETION REPORT - DEBRIS, SLUDGE AND MIXED-CONTAMINANT SOIL REMOVAL - WILDWOOD	# 0f Pages: 48

PROPERTY	Doc Date; 03/01/1995

Resource Type:

Author: , REMEDIATION TECHNOLOGIES INC	Addressee: ; BEATRICE COMPANY	Report

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553622 REMEDIAL ACTION (RA) COMPLETION REPORT - DEBRIS, SLUDGE AND MIXED-CONTAMINANT SOIL REMOVAL - WILD WOOD	# 0f Pages: 291

PROPERTY-APPENDICES A-I	Doc Date; 03/01/1995

Resource Type:

Author: , REMEDIATION TECHNOLOGIES INC	Addressee: ; BEATRICE COMPANY	Report

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553623 REMEDIAL ACTION (RA) COMPLETION REPORT - DEBRIS, SLUDGE AND MIXED-CONTAMINANT SOIL REMOVAL - WILD WOOD	# 0f Pages: 306

PROPERTY - APPENDICES J-U	Doc Date; 03/01/1995

Resource Type:

Author: , REMEDIATION TECHNOLOGIES INC	Addressee: ; BEATRICE COMPANY	Report

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553624 REMEDIAL ACTION (RA) COMPLETION REPORT - DEBRIS, SLUDGE AND MIXED-CONTAMINANT SOIL REMOVAL - WILD WOOD	# 0f Pages: 357

PROPERTY - APPENDIX 5 CONTRACT LABORATORY PROGRAM (CLP) DATA PACKAGES - VOLUME 1 OF 6	Doc Date. 03/01/1995

Resource Type:

Author: , REMEDIATION TECHNOLOGIES INC	Addressee: ; BEATRICE COMPANY	Report

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553625 REMEDIAL ACTION (RA) COMPLETION REPORT - DEBRIS, SLUDGE AND MIXED-CONTAMINANT SOIL REMOVAL - WILD WOOD
PROPERTY - APPENDIX 5 CONTRACT LABORATORY PROGRAM (CLP) DATA PACKAGES - VOLUME 2 OF 6

Author: , REMEDIATION TECHNOLOGIES INC

Addressee:

, BEATRICE COMPANY

# of Pages: 379
Doc Date: 03/01/1995
Resource Type:

Report

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553626 REMEDIAL ACTION (RA) COMPLETION REPORT - DEBRIS, SLUDGE AND MIXED-CONTAMINANT SOIL REMOVAL - WILD WOOD
PROPERTY - APPENDIX 5 CONTRACT LABORATORY PROGRAM (CLP) DATA PACKAGES - VOLUME 3 OF 6

Author: , REMEDIATION TECHNOLOGIES INC

Addressee: BEATRICE COMPANY

# of Pages: 381
Doc Date: 03/01/1995
Resource Type:

Report

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553627 REMEDIAL ACTION (RA) COMPLETION REPORT - DEBRIS, SLUDGE AND MIXED-CONTAMINANT SOIL REMOVAL - WILD WOOD	# 0f Pages: 391

PROPERTY - APPENDIX 5 CONTRACT LABORATORY PROGRAM (CLP) DATA PACKAGES - VOLUME 4 OF 6	Doc Date. 03/01/1995

Resource Type:

Author: , REMEDIATION TECHNOLOGIES INC	Addressee: ; BEATRICE COMPANY	Report

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553628 REMEDIAL ACTION (RA) COMPLETION REPORT - DEBRIS, SLUDGE AND MIXED-CONTAMINANT SOIL REMOVAL - WILD WOOD
PROPERTY - APPENDIX 5 CONTRACT LABORATORY PROGRAM (CLP) DATA PACKAGES - VOLUME 5 OF 6

Author: , REMEDIATION TECHNOLOGIES INC

Addressee:

, BEATRICE COMPANY

# of Pages: 395
Doc Date: 03/01/1995
Resource Type:

Report

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553629 REMEDIAL ACTION (RA) COMPLETION REPORT - DEBRIS, SLUDGE AND MIXED-CONTAMINANT SOIL REMOVAL - WILD WOOD
PROPERTY - APPENDIX 5 CONTRACT LABORATORY PROGRAM (CLP) DATA PACKAGES - VOLUME 6 OF 6

Author: , REMEDIATION TECHNOLOGIES INC

Addressee: BEATRICE COMPANY

# of Pages: 562
Doc Date: 03/01/1995
Resource Type:

Report

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File Break: 09.01 - CORRESPONDENCE (STATE COORDINATION)

599294 EMAIL REGARDING DOWNGRADIENT PROPERTY STATUS (DPS) FILINGS	# 0f Pages: 2

Doc Date: 04/01/2016
Resource Type:

Author: DAVID M SULLIVAN, TRC ENVIRONMENTAL	Addressee: JOSEPH LEMAY US EPA REGION 1	Email

CORP

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Page 41 of 62

546192 CLASS 2-A RESPONSE ACTION OUTCOME (RAO) STATEMENT FORMER JOHN J. RILEY TANNERY SITE, RTN 3-25732 - REVISED
04/03/2013 (TRANSMITTAL LETTER ATTACHED)

Author: , TETRA TECH NUS INC

Addressee: ; MA DEPT OF ENVIRONMENTAL PROTECTION

# of Pages: 947
Doc Date: 04/03/2013
Resource Type:

Report

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599276 REPORT OF ACTIVITIES AND SOIL EXCAVATION PLAN, TANNERY WASTE AND SOIL CONTAMINATION, 228 SALEM STREET

Author: SANDRA M HEBERT, 21E INC

# of Pages: 114
Doc Date: 04/25/1996
Resource Type:

Addressee: MITRA KHADEM, MA DEPT OF ENVIRONMENTAL PROTECTION Letter

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599278 CLASS 2-A RESPONSE ACTION OUTCOME (RAO) STATEMENT FORMER JOHN J. RILEY TANNERY SITE, RTN 3-25732 (TRANSMITTAL # 0f Pages: 219
LETTER ATTACHED)	Doc Date: 01/27/2011

Resource Type:

Author: , TETRA TECH NUS INC	Addressee: , MA DEPT OF ENVIRONMENTAL PROTECTION	Report

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File Break: 09.10 - STATE TECHNICAL AND HISTORICAL RECORDS

599292 RELEASE ABATEMENT MEASURE COMPLETION STATEMENT, ORGANIX LLC (FORMER JOHN J RILEY SITE), 240 SALEM STREET
Author: , RIZZO ASSOCIATES	Addressee: ; MA DEPT OF ENVIRONMENTAL PROTECTION

Access Control:

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# of Pages: 138
Doc Date: 11/14/2006
Resource Type:

Report

599293 PHASE 1 INITIAL SITE INVESTIGATION (SI) AND TIER CLASSIFICATION, ORGANIX LLC (FORMER JOHN J RILEY SITE), 240 SALEM # 0f Pages: 325

STREET	Doc Date; 03/13/2007

Resource Type:

Author: , RIZZO ASSOCIATES	Addressee: , MA DEPT OF ENVIRONMENTAL PROTECTION	Report

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File Break: 10.03 - STATE AND LOCAL ENFORCEMENT RECORDS

493519 LETTER REGARDING NOTICE OF NON-COMPLIANCE AND AUDIT FINDINGS COMPLETION STATEMENT, 228 SALEM STREET,	# 0f Pages: 14

WOBURN, MA (FIGURES ATTACHED)	Doc Date; 08/14/1996

Resource Type:

Author: SANDRA M HEBERT, 21E INC	Addressee: MITRA KHADEM, MA DEPT OF ENVIRONMENTAL PROTECTION Letter

HEIDI PORTER, 21E INC

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493520 LETTER REGARDING NOTICE OF NON-COMPLIANCE AND AUDIT FINDINGS COMPLETION STATEMENT, 228 SALEM STREET,	# 0f Pages: 44

WOBURN, MA (DATA, FIGURES AND TABLES ATTACHED)	Doc Date. 08/14/1996

Author: SANDRA M HEBERT, 21E INC
HEIDI PORTER, 21E INC

Resource Type:

Addressee: MITRA KHADEM, MA DEPT OF ENVIRONMENTAL PROTECTION Letter

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493522 FINAL REPORT, ENVIRONMENTAL SITE ASSESSMENT, 228 SALEM STREET, WOBURN, MA [MARGINALIA]

Author: , 21E INC

Addressee: JOHN J RILEY JR, NONE

# of Pages: 16
Doc Date: 12/26/1990
Resource Type:

Report

Access Control:

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493523 IMMEDIATE RESPONSE ACTION PLAN (IRAP), 228 SALEM STREET, WOBURN, MA (TRANSMITTAL LETTER ATTACHED)

Author: , 21E INC

Addressee: DEPT OF ENVIRONMENTAL PROTECTION

# of Pages: 6

Doc Date: 04/12/1996
Resource Type:

Report

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493524 LETTER REGARDING NOTICE OF AUDITING FINDINGS, 288 SALEM STREET, WOBURN, MA (MAP ATTACHED)

Author: SANDRA M HEBERT, 21E INC

# of Pages: 6
Doc Date: 01/26/1996
Resource Type:

Addressee: MITRA KHADEM, MA DEPT OF ENVIRONMENTAL PROTECTION Letter

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493528 21E ASSESSMENT OF J. J. RILEY PROPERTY, 228 SALEM STREET, WOBURN, MA

Author: , GEOTECHNICAL ENGINEERS INC

Addressee: NUTTER MCCLENNEN & FISH LLP

# of Pages: 27
Doc Date: 04/19/1985
Resource Type:

Report

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493531

MEMO REGARDING 03/08/1996 MEETING RESULTS

Author: MITRA KHADEM, MA DEPT OF
ENVIRONMENTAL PROTECTION

# of Pages: 2
Doc Date: 03/25/1996
Resource Type:

Addressee: PATRICIA DONAHUE, MA DEPT OF ENVIRONMENTAL PROTECT Meeting Document

JACK DUGGAN, MA DEPT OF ENVIRONMENTAL QUALITY
ENGINEERING

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493532 RELEASE NOTIFICATION AND NOTIFICATION OF POTENTIAL RESPONSIBILITY (RELEASE LOG FORMS ATTACHED)

Author: KINGSLEY NDI, MA DEPT OF

ENVIRONMENTAL PROTECTION

Addressee: JOHN RILEY, WEDEL CORP

# of Pages: 5
Doc Date: 02/26/1996
Resource Type:

Letter

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555845 MASSACHUSETTS CONTINGENCY PLAN (MCP) PHASE 2 AND PHASE 3 REPORT FOR THE FORMER JOHN J. RILEY SITE

Author: , TETRA TECH RIZZO

Addressee: MA DEPT OF ENVIRONMENTAL PROTECTION

# of Pages: 728
Doc Date: 03/15/2009
Resource Type:

Report

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File Break: 10.08 - EPA CONSENT DECREES

16982 CONSENT DECREE, CIVIL ACTION 91-11807 MA	# of Pages: 250

Doc Date: 09/28/1990
Resource Type:

Author: ; US EPA REGION 1	Addressee:	Legal Instrument

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Page 46 of 62

457530 COMFORT/STATUS LETTER - 280 SALEM STREET LLC (INCLUDES WASTELAN FORM)

Author: SUSAN STUDLIEN, US EPA REGION 1

Addressee: ROBERT HOLLAND, 280 SALEM STREET LLC

# of Pages: 8
Doc Date: 05/07/2004
Resource Type:

Letter

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559966 [REDACTED] 104 INFORMATION REQUEST RESPONSE - WHITNEY BARREL CO INC,

Author: JOHN WHITNEY, WHITNEY BARREL CO INC
RUTH WHITNEY, WHITNEY BARREL CO INC

Addressee: BARBARA NEWMAN, US EPA REGION 1

# of Pages: 12
Doc Date: 02/16/1988
Resource Type:

Letter

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595616 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - WR GRACE & CO - CONN

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: SETH D JAFFE, FOLEY HOAG LLP

# of Pages: 6

Doc Date: 07/06/2017
Resource Type:

Letter

, WR GRACE & CO - CONN

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595617 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - WILDWOOD CONSERVATION CORP # 0f Pages: 4

Doc Date: 07/06/2017
Resource Type:

Author: LYNNE A JENNINGS, US EPA REGION 1	Addressee: JOHN J RILEY JR, WILDWOOD CONSERVATION CORP	Letter

, WILDWOOD CONSERVATION CORP

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595618 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - SYLVANIA

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: DAVID M FELDMAN, VERIZON INC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

, SYLVANIA

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595619 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - VARIAN

Author: LYNNE A JENNINGS, US EPA REGION 1

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Addressee: ROBERT HALLIDAY, VARIAN SEMICONDUCTOR EQUIPMENT Letter

ASSOCIATES INC
, VARIAN

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595620 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - VARIAN MEDICAL SYSTEMS

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: DOW WILSON, VARIAN MEDICAL SYSTEMS

, VARIAN

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

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595622 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - UNIFIRST CORP

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: GREGORY A BIBLER, GOODWIN PROCTOR LLP

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

, UNIFIRST CORP

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595623 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - STEPAN CO

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: KEVIN M MCKENNA, LATSHA DAVIS AND MCKENNA

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

, STEPAN CO

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595624 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - SAMUEL CABOT INC

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: JEFFREY J HAYWARD, VALSPAR CORPORATION THE

SAMUEL CABOT INC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

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595625 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - S & J MANAGEMENT INC

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: J JAMES KONAXIS, S & J MANAGEMENT INC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

SUSAN M WHITNEY, S & J MANAGEMENT INC

S & J MANAGEMENT INC

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595626 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - OSRAM SYLVANIA INC

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: CHRISTINE SHEEDY, OSRAM SYLVANIA

# of Pages: 9
Doc Date: 07/06/2017
Resource Type:

Letter

, OSRAM SYLVANIA

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595627 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - ORGANIX LLC

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: BARBARA K LANDAU, NOBLE AND WICKERSHAM LLP

, ORGANIX LLC

# of Pages: 6

Doc Date: 07/06/2017
Resource Type:

Letter

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595628 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - OLIN CORP

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: CURTIS M RICHARDS, OLIN CORP

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

, OLIN CORP

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595629 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - OLD OIL REALTY TRUST

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: GEORGE P. LUKER, ATTORNEY AT LAW

# of Pages: 6

Doc Date: 07/06/2017
Resource Type:

Letter

JOAN E MURPHY, OLD OIL REALTY TRUST

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, OLD OIL REALTY TRUST

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595630 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - NEW ENGLAND PLASTICS CORP

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: FRANKLIN STEARNS, K&L GATES LLP

, NEW ENGLAND PLASTICS

# of Pages: 6

Doc Date: 07/06/2017
Resource Type:

Letter

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595631 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - MURPHY'S WASTE OIL SERVICES	# 0f Pages: 4

Doc Date: 07/06/2017
Resource Type:

Author: LYNNE A JENNINGS, US EPA REGION 1	Addressee: TIMMERY FITZPATRICK, CLEAN HARBORS	Letter

, CLEAN HARBORS ENVIRONMENTAL SERVICES INC
, MURPHY'S WASTE OIL SERVICE INC

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595632 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - LAMCO CHEMICAL CO

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: JAMES G LAMM, LAMCO CHEMICAL CO INC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

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Record of Decision (ROD), 09-29-2017

AR Collection Index Report
***For External Use***

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Page 52 of 62

595633 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - KINGSTON STEEL DRUM

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: gRIC BERRY, MALLINCKRODT US HOLDINGS, LLC

, GREAT LAKES CONTAINER CORP

KINGSTON STEEL DRUM

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

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595634 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - KEK REALTY TRUST

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: SUSAN M WHITNEY, KEK REALTY TRUST

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

JOHN E WHITNEY III, KEK REALTY TRUST

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595635 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - HONEYWELL INTERNATIONAL

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: DAVID M COTE, HONEYWELL INTERNATIONAL INC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

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Page 53 of 62

595636 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - GOULSTON TECHNOLOGIES

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: ETHAN R. WARE, MCNAIR LAW FIRM, P.A.

# of Pages: 6

Doc Date: 07/06/2017
Resource Type:

Letter

, GEORGE A GOULSTON

, GOULSTON TECHNOLOGIES INC

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595637 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - GILLETTE

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: NATHANIEL S OROSZ, PROCTOR & GAMBLE

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

, GILLETTE CO

Access Control:

Uncontrolled

595638 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - CUMMINGS PROPERTIES
MANAGEMENT

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: CRAIG ZAIDY, CUMMINGS PROPERTY LLC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

, CUMMINGS PROPERTIES MANAGEMENT INC

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***For External Use***

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595640 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - BOUTWELL MORSE

Author: LYNNE A JENNINGS, US EPA REGION 1	Addressee: MICHAEL BOUTWELL, NONE

ROBERT C BOUTWELL, NONE
WILLIAM BOUTWELL, NONE
GRACE MORSE, NONE

JEFFREY B RENTON, GILBERT & RENTON LLC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

Access Control:

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595641 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - BOSTON EDISON CO

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: JEFFREY N, ESQ STEVENS, EVERSOURCE ENERGY

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

, BOSTON EDISON CO/NSTAR ELECTRIC AND GAS CO

Access Control:

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595642 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - BEATRICE CO

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: JAMES SANDLER, LOWENSTEIN SANDLER LLP

# of Pages: 5
Doc Date: 07/06/2017
Resource Type:

Letter

, BEATRICE COMPANY

Access Control:

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,CONAGRA FOODS INC

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Record of Decision (ROD), 09-29-2017

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***For External Use***

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Page 55 of 62

595643 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - BAYERCROPSCIENCE INC

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: LUKE METTE, STAUFFER MANAGEMENT COMPANY

, BAYER CROPSCIENCE INC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

Access Control:

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595644 NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - 280 SALEM STREET LLC

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: ROBERT L HOLLAND, HOLLAND ARENA INC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

, 280 SALEM STREET LLC

Access Control:

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595645 RETURNED NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - HONEYWELL

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: THOMAS R MAHER, BULL HN INFORMATION SYSTEMS INC

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

, HONEYWELL

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***For External Use***

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595646 RETURNED NOTIFICATION TO POTENTIALLY INTERESTED PARTY (PIP) OF PROPOSED CLEANUP PLAN - VARIAN INC

Author: LYNNE A JENNINGS, US EPA REGION 1

Addressee: DANIEL W PEIXOTO, VARIAN

# of Pages: 4
Doc Date: 07/06/2017
Resource Type:

Letter

Access Control:

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596283 [REDACTED] 104 INFORMATION REQUEST RESPONSE - ABERJONA AUTO PARTS

Author: CLIFFORD BOUTWELL, ABERJONA AUTO
PARTS INC

DENNIS J CURRAN, CURRAN & CAMERON

Addressee: BARBARA NEWMAN, US EPA REGION 1

# of Pages: 20
Doc Date: 01/27/1988
Resource Type:

Letter

Access Control:

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599271 ASSESSOR INFORMATION - 250 SALEM STREET, MURPHY PROPERTY

Author: , VISION GOVERNMENT SOLUTIONS

Addressee:

# of Pages: 3

Doc Date: 02/10/2017
Resource Type:

Report

Access Control:

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Record of Decision (ROD), 09-29-2017

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***For External Use***

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Page 57 of 62

599272 ASSESSOR INFORMATION - 252 SALEM STREET, MURPHY PROPERTY

Author: , VISION GOVERNMENT SOLUTIONS

Addressee:

# of Pages: 3

Doc Date: 02/10/2017
Resource Type:

Report

Access Control:

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599273 ASSESSOR INFORMATION - 256 SALEM STREET, WHITNEY PROPERTY

Author: , VISION GOVERNMENT SOLUTIONS

Addressee:

# of Pages: 4
Doc Date: 02/10/2017
Resource Type:

Report

Access Control:

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599274 ASSESSOR INFORMATION - 270 SALEM STREET, ABERJONA PROPERTY

Author: , VISION GOVERNMENT SOLUTIONS

Addressee:

# of Pages: 3

Doc Date: 02/10/2017
Resource Type:

Report

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599275 ASSESSOR INFORMATION - 280 SALEM STREET, ABERJONA PROPERTY	# 0f Pages: 3

Doc Date: 02/10/2017
Resource Type:

Author: , VISION GOVERNMENT SOLUTIONS	Addressee:	Report

Access Control:

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File Break: 13.03 - NEWS CLIPPINGS/PRESS RELEASES

620706 NEWS RELEASE: EPA PROPOSES CLEANUP PLAN FOR THE WELLS G&H SUPERFUND SITE IN WOBURN, MA - PUBLIC COMMENT IS # 0f Pages: 2

OPEN UNTIL 08/14/2017	Doc Date; 07/12/2017

Resource Type:

Author: , US EPA REGION 1	Addressee:	Publication

Access Control:

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620766 PUBLIC NOTICE: EPA EXTENDS PUBLIC COMMENT PERIOD FOR THE PROPOSED CLEANUP PLAN FOR THE WELLS G&H	# 0f Pages: 1

SUPERFUND SITE IN WOBURN, MA	Doc Date; 08/10/2017

Resource Type:

Author: , US EPA REGION 1	Addressee:	Publication

Access Control:

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Record of Decision (ROD), 09-29-2017

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***For External Use***

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Page 59 of 62

622306 PRESS RELEASE: EPA EXTENDS PUBLIC COMMENT PERIOD FOR THE PROPOSED CLEANUP PLAN FOR THE WELLS G&H
SUPERFUND SITE IN WOBURN, MA

Author: , US EPA REGION 1

Addressee:

# of Pages: 1
Doc Date: 08/21/2017
Resource Type:

Publication

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622361 PUBLIC NOTICE AS PUBLISHED IN BOSTON GLOBE AND WOBURN DAILY TIMES: US EPA ANNOUNCES A 30-DAY EXTENSION TO THE # 0f Pages: 1

30-DAY PUBLIC COMMENT PERIOD ON THE PROPOSED CLEANUP PLAN FOR THE WELLS G&H SUPERFUND SITE, WOBURN, MA Doc Date; 08/l 8/2017

Resource Type:

Author: , US EPA REGION 1	Addressee:	Publication

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622362 PUBLIC NOTICE AS PUBLISHED IN BOSTON GLOBE: US EPA ANNOUNCES A 30-DAY PUBLIC COMMENT PERIOD ON THE PROPOSED # 0f Pages: 1

CLEANUP PLAN FOR THE WELLS G&H SUPERFUND SITE, WOBURN, MA	Doc Date. 07/14/2017

Resource Type:

Author: , US EPA REGION 1	Addressee:	Publication

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Page 60 of 62

620705 SAVE THE DATE CARD, PUBLIC MEETING 07/13/2017, PUBLIC HEARING 08/03/2017

Author: , US EPA REGION 1

Addressee:

# of Pages: 2
Doc Date: 07/01/2017
Resource Type:

Publication

Access Control:

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620747 PROPOSED PLAN PUBLIC MEETING PRESENTATION, SOUTHWEST PROPERTIES (SWP)

Author: JOSEPH LEMAY, US EPA REGION 1

Addressee:

# of Pages: 29
Doc Date: 07/13/2017
Resource Type:

Meeting Document

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620753 PROPOSED PLAN PRESENTATION BEFORE PUBLIC HEARING, SOUTHWEST PROPERTIES (SWP)

Author: JOSEPH LEMAY, US EPA REGION 1

Addressee:

# of Pages: 13
Doc Date: 08/03/2017
Resource Type:

Meeting Document

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***For External Use***

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621412 [REDACTED] PUBLIC MEETING FOR PROPOSED CLEANUP PLAN SIGN-IN SHEET

Author: , US EPA REGION 1

Addressee:

# of Pages: 2
Doc Date: 07/13/2017
Resource Type:

Meeting Document

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621414 [REDACTED] PUBLIC HEARING 08/03/17 SIGN-IN SHEET

Author: , US EPA REGION 1	Addressee:

# of Pages: 2
Doc Date: 08/03/2017
Resource Type:

Meeting Document

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622307 PUBLIC HEARING TRANSCRIPT

Author: JENNIFER DOHERTY, EPPLEY COURT
REPORTING LLC

Addressee:

# of Pages: 12
Doc Date: 08/03/2017
Resource Type:

Meeting Document

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File Break: 17.04 - NON-PRINT MATERIALS

485979 SANB ORN FIRE INSURANCE MAP OF WHITNEY BARREL

Author:	Addressee:

Access Control:

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# of Pages: 1
Doc Date: 01/01/1969
Resource Type:

Figure/Map/ Drawing

File Break: 20.01 - ADMINISTRATIVE RECORD INDEXES

620708 WELLS G&H OPERABLE UNIT (OU) 4 RECORD OF DECISION (ROD) PROPOSED PLAN ADMINISTRATIVE RECORD (AR) FILE INDEX # 0f Pages: 51

Doc Date: 07/01/2017
Resource Type:

Author: ; US EPA REGION 1	Addressee:	Administrative Record

Index

Access Control:

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Number of Documents in Administrative Record: 184

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Selected Key Guidance Documents

EPA Guidance Documents may be reviewed at the OSRR Records and Information Center in Boston, MA

DOCNUMBER

DOCDATE

TITLE

11-196769

01-Jan-80

Ambient water quality criteria for DDT

11-101118

27-Sep-85

OSWER Directive 9850.3: Chemical, Physical, and Biological Properties of Compounds Present at Hazardous Waste
Sites, Final Report; Compendium 5001

11-128301

Ol-Oct-88

Guidance for Conducting Remedial Investigations and Feasibility Studies Under CERCLA, Interim Final, OSWER

Directive 9355.3-01

11-191

Ol-Dec-89

RISK ASSESSMENT GUIDANCE FOR SUPERFUND (RAGS), VOLUME l-HUMAN HEALTH EVALUATION MANUAL, PART A

11-137293

01-Jan-90

The 1990 National Contingency Plan, DRAFT

11-190591

25-Mar-91

RISK ASSESSMENT GUIDANCE FOR SUPERFUND VOLUME 1: HUMAN HEALTH EVALUATION MANUAL. SUPPLEMENTAL

GUIDANCE: "STANDARD DEFAULT EXPOSURE FACTORS"

11-130917

22-Apr-91

MEMO REGARDING ROLE OF THE BASELINE RISK ASSESSMENT IN SUPERFUND REMEDY SELECTION DECISIONS

11-192

Ol-Dec-91

RISK ASSESSMENT GUIDANCE FOR SUPERFUND (RAGS). VOLUME 1 - HUMAN HEALTH EVALUATION MANUAL. PART B:

11-127549

Ol-May-92

SUPPLEMENTAL GUIDANCE TO RAGS: CALCULATING THE CONCENTRATION TERM

11-190663

Ol-Dec-93

WILDLIFE EXPOSURE FACTORS HANDBOOK, VOLUME 1 OF II

11-157100

Ol-Feb-94

GUIDANCE MANUAL FOR THE INTEGRATED EXPOSURE UPTAKE BIOKINETIC MODEL FOR LEAD IN CHILDREN

11-156952

14-Jul-94

MEMO REGARDING REVISED INTERIM SOIL LEAD GUIDANCE FOR CERCLA SITES AND RCRCA CORRECTIVE ACTION

FACILITIES

11-207

Ol-May-96

Soil Screening Guidance: Technical Background Document [EPA # 540-R-95-1281

11-176382

Ol-Dec-96

Region 1 EPA-NE Data Validation Functional Guidelines for Evaluating Environmental Analyses

11-157941

Ol-Jun-97

ECOLOGICAL RISK ASSESSMENT GUIDANCE FOR SUPERFUND: PROCESS FOR DESIGNING AND CONDUCTING

ECOLOGICAL RISK ASSESSMENTS - INTERIM FINAL

11-158350

Ol-Jul-97

EPA Health Effects Assessment Summary Tables FY 1997 Update

11-190104

Ol-Aug-97

EXPOSURE FACTORS HANDBOOK 1997

11-196795

Ol-Jan-98

MTBE Fact Sheet #2 Remediation of MTBE Contaminated Soil and Groundwater

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Selected Key Guidance Documents

EPA Guidance Documents may be reviewed at the OSRR Records and Information Center in Boston, MA

DOCNUMBER

DOCDATE

TITLE

11-160616

24-Mar-98

GUIDANCE FOR IMPLEMENTING SUPERFUND REFORM INITIATVE 9a: RISK SHARING. OSWER DIRECTIVE 9010.02

11-189662

Ol-Apr-98

GUIDELINES FOR ECOLOGICAL RISK ASSESSMENT

11-500009392

Ol-Jul-99

A GUIDE TO PREPARING SUPERFUND PROPOSED PLANS. RECORDS OF DECISION. AND OTHER REMEDY SELECTION

DECISION DOCUMENTS, OSWER DIRECTIVE 9200.1-23P

11-175137

01-Dec-01

RISK ASSESSMENT GUIDANCE FOR SUPERFUND: VOLUME 1 HUMAN HEALTH EVALUATION MANUAL RAGS ) PART D.

STANDARDIZED PLANNING. REPORTING. AND REVIEW OF SUPERFUND RISK ASSESSMENTS) - FINAL

9-1174885

01-Jan-02

Region 9 Biological Technical Assistance Group (BTAG) Recommended Toxicity Reference Values for Birds and
Mammals. November 21

11-190303

31-Oct-02

CHARACTERIZING RISKS POSED BY PETROLEUM CONTAMINATED SITES: IMPLEMENTATION OF THE MADEP VPH/EPH
APPROACH

11-78

01-Nov-02

OSWER DRAFT GUIDANCE FOR EVALUATING THE VAPOR INTRUSION TO INDOOR AIR PATHWAY FROM
GROUNDWATER AND SOILS (SUBSURFACE VAPOR INTRUSION GUIDANCE)

11-190669

01-Dec-02

CALCULATING UPPER CONFIDENCE LIMITS FOR EXPOSURE POINT CONCENTRATIONS AT HAZARDOUS WASTE SITES

11-175878

01-Dec-02

SUPPLEMENTAL GUIDANCE FOR DEVELOPING SOIL SCREENING LEVELS FOR SUPERFUND SITES - OSWER 9355.4-24

11-174559

01-Jan-03

RECOMMENDATIONS FROM THE TECHNICAL REVIEW WORKGROUP FOR LEAD FOR AN APPROACH TO ASSESSING

RISKS ASSOCIATED WITH ADULT EXPOSURES TO LEAD IN SOIL EPA-540-R-03-001

11-190659

22-Aug-03

RCRA ECOLOGICAL SCREENING LEVELS

11-176288

01-Nov-03

GUIDANCE REGARDING ASSESSING INTERMITTENT OR VARIABLE EXPOSURES AT LEAD SITES. EPA 540-R-03-008.

OSWER NO. 9285.7-76

11-196771

01-Nov-03

Ecological Soil Screening Levels for Aluminum. Interim Final.

11-196782

01-Nov-03

Ecological Soil Screening Levels for Iron. Interim Final.

11-136

05-Dec-03

MEMO REGARDING REVISIONS TO HUMAN HEALTH TOXICITY VALUES IN SUPERFUND RISK ASSESSMENTS

11-195

01-Jul-04

RISK ASSESSMENT GUIDANCE FOR SUPERFUND (RAGS). VOLUME 9 - HUMAN HEALTH EVALUATION MANUAL. PART E:

SUPPLEMENTAL GUIDANCE FOR DERMAL RISK ASSESSMENT

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Selected Key Guidance Documents

EPA Guidance Documents may be reviewed at the OSRR Records and Information Center in Boston, MA

DOCNUMBER

DOCDATE

TITLE

11-196798

01-Jan-05

Procedures for the Derivation of Equilibrium Partitioning Sediment Benchmarks (ESBs) for the Protection of Benthic
Organisms: Metal Mixtures (Cadmium, Copper, Lead, Nickel, Silver and Zinc)

11-196772

01-Feb-05

Ecological Soil Screening Levels for Antimony. Interim Final.

11-196774

01-Feb-05

Ecological Soil Screening Levels for Barium. Interim Final.

11-196775

01-Feb-05

Ecological Soil Screening Levels for Beryllium. Interim Final.

11-196773

01-Mar-05

Ecological Soil Screening Levels for Arsenic. Interim Final.

11-196776

01-Mar-05

Ecological Soil Screening Levels for Cadmium. Interim Final.

11-196778

01-Mar-05

Ecological Soil Screening Levels for Cobalt. Interim Final.

11-196783

01-Mar-05

Ecological Soil Screening Levels for Lead. Interim Final.

11-196790

01-Apr-05

Ecological Soil Screening Levels for Vanadium. Interim Final.

11-196797

01-Nov-05

Polychlorinated Biphenyl (PCB) Site Revitalization Guidance Under the Toxic Substances Control Act (TSCA)

3-2246068

01-Jul-06

Region 3 BTAG Freshwater Screening Benchmarks

11-196789

01-Sep-06

Ecological Soil Screening Levels for Silver. Interim Final.

11-196779

01-Feb-07

Ecological Soil Screening Levels for Copper. Interim Final.

11-196785

01-Mar-07

Ecological Soil Screening Levels for Nickel. Interim Final.

11-196780

01-Apr-07

Ecological Soil Screening Levels for DDT and Metabolites. Interim Final.

11-196781

01-Apr-07

Ecological Soil Screening Levels for Dieldrin. Interim Final.

11-196784

01-Apr-07

Ecological Soil Screening Levels for Manganese. Interim Final.

11-196786

01-Apr-07

Ecological Soil Screening Levels for Pentachlorophenol. Interim Final.

11-176289

01-May-07

USER'S GUIDE FOR INTEGRATED EXPOSURE UPTAKE BIOKINETIC MODEL FOR LEAD IN CHILDREN (IEUBK), EPA 540-K-

01-005. OSWER NO. 9285.7-42

11-196787

01-Jun-07

Ecological Soil Screening Levels for Polycyclic Aromatic Hydrocarbons (PAHs). Interim Final.

11-196791

01-Jun-07

Ecological Soil Screening Levels for Zinc. Interim Final.

11-196788

01-Jul-07

Ecological Soil Screening Levels for Selenium. Interim Final.

11-196777

01-Apr-08

Ecological Soil Screening Levels for Chromium. Interim Final.

11-196792

01-Jun-08

Framework for Application of the Toxicity Equivalence Methodology for Polychlorinated Dioxins, Furans, and
Biphenyls in Ecological Risk Assessment. Office of the Science Advisor

11-196796

01-Jan-09

National Recommended Water Quality Criteria

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Selected Key Guidance Documents

EPA Guidance Documents may be reviewed at the OSRR Records and Information Center in Boston, MA

DOCNUMBER

DOCDATE

TITLE

11-150131

26-Jun-09

Update of the Adult Lead Methodology's Default Baseline Blood Lead Concentration and Geometric Standard
Deviation Parameters, OSWER 9200.2-82 [Transmittal Memorandum and Concurrences Copy Included]

11-176381

30-Sep-09

Provisional Peer-Reviewed Toxicity Values for Complex Mixtures of Aliphatic and Aromatic Hydrocarbons

11-500020882

20-Sep-10

REVISED GUIDANCE ON COMPILING ADMINISTRATIVE RECORDS FOR CERCLA RESPONSE

11-190077

01-Dec-10

RECOMMENDED TOXICITY EQUIVALENCE FACTORS (TEFs) FOR HUMAN HEALTH RISK ASSESSMENTS OF 2.3.7.8-

TETRACHLORODIBENZO-P-DIOXIN AND DIOXIN-LIKE COMPOUNDS

11-190592

01-Sep-ll

EXPOSURE FACTORS HANDBOOK, 2011 EDITION

11-196770

01-Apr-12

Drinking water standards and health advisories

11-196793

Ol-Jan-13

Ground Water Issue Paper: Synthesis Report on State of Understanding of Chlorinated Solvent Transformation

11-190433

Ol-Jan-14

TECHNICAL FACT SHEET - 1,4-DIOXANE

11-196794

19-Feb-16

Light Nonaqueous Phase Liquids (LNAPL) and the MCP: Guidance for Site Assessment and Closure

11-197872

14-Nov-16

UPDATE TO 2010 REVISED GUIDANCE ON COMPILING ADMINISTRATIVE RECORDS FOR CERCLA RESPONSE ACTIONS

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