PB95-963708
EPA/ROD/R01-95/108
February 1996
EPA Superfund
Record of Decision:
New London Naval Submarine Base,
(O.U. 1), Area A Landfill, Groton, CT
9/26/1995
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RECORD OF DECISION
SOURCE CONTROL OPERABLE UNIT
AREA A LANDFILL
NAVAL SUBMARINE BASE
GROTON, CONNECTICUT
SEPTEMBER 1995
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TABLE OF CONTENTS
Page
TABLE OF CONTENTS i
DECLARATION FOR THE RECORD OF DECISION iii
I. SITE NAME, LOCATION, AND DESCRIPTIONS 1
n. SITE HISTORIES AND ENFORCEMENT ACTTVmES 4
m. COMMUNITY PARTICIPATION 7
IV. SCOPE AND ROLE OF RESPONSE ACTION 5"
V. SUMMARY OF SITE CHARACTERISTICS 10
VI. SUMMARY OF SITE RISKS 14
VH. DEVELOPMENT AND SCREENING OF REMEDIAL ALTERNATIVES .... 20
VIE. DESCRIPTION OF ALTERNATIVES 21
DC. SUMMARY OF THE COMPARATIVE ANALYSIS ALTERNATIVES 24
X. THE SELECTED REMEDY 28
XI. STATUTORY DETERMINATIONS . 29
Xn. DOCUMENTATION OF NO SIGNIFICANT CHANGES 35
XIE. STATE ROLE 36
LIST OF FIGURES
Figure 1-1: NSB-NLON Location 2
Figure 1-2: Location of the Area A Landfill at the NSB-NLON 3
Figure 1-3: Area A Landfill 5
Figure 4-1: Cap Diagram 11
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LIST OF TABLES
Table 5-1: Chemical Concentrations in Area A Landfill Soils 13
Table 5-2: Chemical Concentrations in Area A Landfill Groundwater 14
Table 11-1: Detailed Alternative Cost Estimate Area A Landfill -
Alternative 2L-3, Capping 33
Table 11-2: Preliminary Cost Estimates for a Leachate/Groundwater Collection
and Disposal System for the Area A Landfill 34
LIST OF APPENDICES
Appendix A: Responsiveness Summary
Appendix B: Comparative Analysis of Alternatives
Appendix C: ARAR Summary Tables
Appendix D: Declaration of Concurrence
11
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DECLARATION FOR THE RECORD OF DECISION
SITE NAME & LOCATION
Operable Unit 1 - Area A Landfill
Naval Submarine Base
Groton, Connecticut
STATEMENT OF BASIS & PURPOSE
This decision document presents the selected source control remedial action for Operable unit
1, the Area A Landfill, at the Naval Submarine Base ("NSB") in Groton, Connecticut. This
decision document was developed in accordance with the Comprehensive Environmental
Response, Compensation, and Liability Act of 1980 ("CERCLA"), as amended by the
Superfund Amendments and Reauthorization Act of 1986 ("SARA") and with the National
Oil and Hazardous Substances Pollution Contingency Plan ("NCP"). Through this
document, the Navy plans to Tninimire the threat to human health and the environment posed
by the presence of the landfill through the implementation of a source control action. This
decision is based upon the contents of the Administrative Record for the Area A Landfill.
The Adrninistrative Record is available at the NSB in Groton, Connecticut.
Both the U.S. Environmental Protection Agency and the Connecticut Department of
Environmental Protection concur with the selected remedial action.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this site, if not addressed by
implementing the response action selected in this Record of Decision ("ROD"), may present
a current or potential threat to human health and the environment.
DESCRIPTION OF THE SELECTED REMEDY
This remedy is the first of two operable units for the site and addresses source control.
Management and migration of contaminants in the groundwater will be addressed as a
separate operable unit.
The major components of the selected remedy include:
*- Capping of the site with a RCRA Subtitle C multi-layer cap.
* Landfill gas controls to manage landfill gas migration.
* Surface controls to minimize erosion and manage runoff.
> Use of fencing and institutional controls to control site access and future site use.
ui
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»> Provisions for conducting additional studies, including determining if additional
measures, beyond capping, such as a leachate/groundwater collection system, must be
taken to further contain contaminants and gnhanr^ stability.
> A leachate/groundwater collection system may be installed to further contain landfill
wastes and to stabilize the cap if pre-design studies indicate that one is necessary.
+ Five -year review.
STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the environment, complies with
Federal and State requirements that are applicable or relevant and appropriate to the remedial
action, and is cost-effective. This source control remedial action uses permanent solutions
and alternative treatment technologies to the maximum extent practicable. The selected
remedy does not satisfy the statutory preference for remedies that employ treatment that
reduces toxicity, mobility, or volume as a principal element because treatment of the entire
landfill is not practicable. The selected remedy will reduce mobility of contaminants through
its containment features. Because this remedy will result hi contaminants remaining at the
site above levels that allow unlimited use and unrestricted exposure, the Navy will review the
remedial action to the extent required by law, to assure that it continues to protect human
health and the environment.
IV
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The foregoing represents the selection of a remedial action by the Department of the Navy
and the U.S. Environmental Protection Agency, Region I, with concurrence of the
Connecticut Department of Environmental Protection. Concur and recommend for immediate
implementation:
tSptain Leo Dominiqui
Title: Captain, U.S. Navy
Commanding Officer
Naval Submarine Base
Groton, Connecticut
Date:
By: yr^, ['71 < U!.^ _ Date:
jxMda M Murphy / tf
Title: Director, Waste Management Division
U.S. Environmental Protection Agency, Region I
JFK Federal Building
Boston, Massachusetts
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DECISION SUMMARY
I. SITE NAME. LOCATION. AND DESCRIPTIONS
The United States Navy Submarine Base - New London ("NSB-NLON") was placed
on the National Priorities List ("NPL") on August 30, 1990 by the United States
Environmental Protection Agency ("EPA") pursuant to the Comprehensive Environmental
Response and Liability Act ("CERCLA") of 1980. There are several sites within NSB-
NLON that are being addressed by CERCLA. This Record of Decision ("ROD") relates to
soil contamination at the Area A Landfill site within the NSB-NLON.
The NSB-NLON consists of approximately 547 acres of land and associated buildings
in southeastern Connecticut in the towns of Ledyard and Groton. NSB-NLON is situated on
the east bank of the Thames River, approximately 6.0 miles north of Long Island Sound, and
is bounded to the east by the Connecticut Route 12, to the south by Crystal Lake Road, and _
to the west by the Thames River. The northern border is a low ridge that trends
approximately east-southeast from the river. Figures 1-1 and 1-2 show the NSB-NLON
location and the Area A Landfill location, respectively.
NSB-NLON currently provides a base command for naval submarine activities in the
Atlantic Ocean. Additionally, NSB-NLON includes housing for Navy personnel and their
familie.^ submarine training facilities, military offices, medical facilities, and facilities
designed for the maintenance, repair, and overhaul of submarines.
Land use adjacent to the NSB-NLON is generally residential or commercial.
Residential developments border the NSB-NLON to the north and extend north into the
Gales Ferry section of Ledyard. Property along Route 12 to the east of the NSB-NLON
consists of widely spaced private homes and open, wooded land. Further south on Route 12,
development is a mixture of commercial and residential properties that include automobile
sales and repair facilities, convenience stores, restaurants, a church, and a gasoline station.
Private residences and an automobile service station are located along the south side of the
NSB-NLON along Crystal Lake Road; further south is housing for Navy personnel.
The Groton Water Department supplies potable water to NSB-NLON. The primary
sources of the Groton water supply are reservoirs that are supplemented with wells. The
water supplies are located within the Poquonock River Watershed, located east of NSB-
NLON, which is not within the NSB-NLON watershed. Groundwater at NSB-NLON is not
used for potable water.
The land around NSB-NLON consists of a series of low bedrock ridges mat trend
generally north to south. Lowlands between the ridges are commonly wetlands and poorly.
drained stream valleys. The Thames River adjacent to the west of NSB-NLON is flanked by
glacially-derived terrace deposits and more recent flood-plain deposits.
The topography of NSB-NLON (see Figure 1-1) is dominated by bedrock ridges in
the northern (elevation 180 feet mean sea level ["MSL"]) and central (elevation 230 feet
MSL) portions of the NSB-NLON, as well as an off-site ridge (Baldwin Hill, elevation 245
feet MSL) to the east. The low-lying area (elevation 50 feet MSL) between these ridges
slopes to the west (USGS, 1984). The eastern portion of the area is a wetland (Area A)
. ' 1
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2; ./'. '
*% t ^ * j.'j'.
'y /til/}*!.
7 S
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LsJL l^:.'>i*
NEW LONDON
NAVAL SUBMARME BASE
f ^ \VV/
? »-*-sr* ^"\ \\.\
DECISION SIAMARY
AREA *A* LANDFLL
NAVAL SUBMARME BASE - NEW LONDON
GROTON. CT
SOOfCE llrna»nBi. CT
U&&S. TopomMe IVUp
FIGURE M
NSB-NLON LOCATION
ATLANTIC QMRONMENTAL SBWICES. INC.
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CO
LU
AREA 'A' LANDFILL
DBOSJON SUMMARY
AREA'Af LANDFE!
NAVAL SUBMARINE BASE - NEW LONDON
GROTDN. CT
SOURCE: Noral Submarine Base
v Eustno CondTbons
I April 1985 ^
1 Louraro Di9iMcnn9 Associotc
t
0 600 1200
GRAPHIC SCALE M FEET
FIGURE 1-2
LOCATION OF AREA A LANDFILL
ATLANTIC BMRONMEHTAL SERVICES. MC.
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which drains through an earthen dike into an area that is 30 to 40 feet below the elevation of
the wetland. The southern and western portions of NSB-NLON are generally flat with sparse
bedrock outcrops. The topography in several areas of NSB-NLON has been altered by
hmdfilling and quarry ins.
The Area A Landfill is located hi the northeastern and north-central section of NSB-
NLON. The site is approximately 13 acres in size. The Area A landfill is a relatively flat
area bordered by a steep, wooded hillside that rises to the south, a steep wooded ravine to
the west, and a wetland, referred to as the Area A Wetland, to the north. Historic aerial
photographs of the site indicate that filling in the eastern portion of the site occurred
separately from landfilling hi the western portion. Further investigations are to be performed
hi this area of the landfill and, based on those results, a decision will be made as to whether
or not remedial activities are necessary in this area. Runoff from the landfill drains as
overland flow north into the Area A Wetland, which discharges to the Area A Downstream
and ultimately to the Thames River. The Area A Landfill is depicted hi Figure 1-3.
EL. SITE HISTORTFS \ND ENFORCEMENT ACnVITIES
A. Site History
In 1867, the state of Connecticut donated a 112-acre parcel on the east bank of the
Thames River to the Navy. The Navy began using the property in 1868 when it was
officially designated as a Navy Yard. The property was then used as a mooring site for
small craft and obsolete warships, and as a coaling station for the Atlantic fleet.
The Navy Department designated the site a Submarine Base in 1916. During World
War 1, facilities at the base were expanded extensively; 6 piers and 81 buildings were added.
In 1917, a submarine school was established and, in 1918, the Submarine Medical Center
was founded.
NSB-NLON experienced another period of growth during World War n. Between
1935 and 1945 the Navy built in excess of 180 buildings and expanded NSB-NLON from
112 to 497 acres through the acquisition of adjacent land.
The growth of NSB-NLON continued after World War n. The Medical Research
Laboratory was established in 1946. In 1968 the status of the Submarine School was
changed from an activity to a command and became the largest tenant on the base. The
Naval Submarine Support Facility was established in 1974 and the Naval Undersea Medical
Institute was established in 1975. NSB-NLON currently consists of over 300 buildings on
547 acres of land (U.S. Navy, 1988).
The Area A Landfill opened sometime prior to 1957. From 1963 to 1973,
nonsalvageable materials generated by submarines and base operations were disposed in the
Area A Landfill There are no records indicating the volume or type of waste disposal in
the landfill. However, they may include radioactive wastes and medical wastes from the
hospital; industrial wastes from ship repair and maintenance facilities; commercial/residential
wastes from housing and office facilities; and bulky wastes from construction activities. On-
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CONCRETT'
PAD
NOTES:
UNDERGROUND unurr LOCATIONS ARE APPROXBWIE.
a»s£ MAP AM> unnr WFORMWION FROM MAPS
OT NSB-NLON PREPARED BT UXIREIRO ENCMEERINC
ASSOCUTG5. DEC. 1980. O£WnONS ARE BASED ON.
NS8-NLON DATUM WHCH B 1.41 FEET BELOW NGVO.
3. PHASE I IB SAMPLE LOCATIONS ARE SHOWN.
4. THE LOCATION OF BORINGS Z7TB28 THROUGH 27TB32
(NEAR CONCRETE PAD) WOL BE OCTERMNED M THE FIELD
AS NECESSARY FOR SETTER DEFINITION OF SOURCE AREAS.
DECISION SUMMARY
AREA *A* LANDFILL
NAVAL SUBMARME BASE-NEW LONDON
QROTON.CONN.
10 ensr COMTOUR
I in i
STORM SMCt
name vs
AREA A LANDFILL
AILANiH, ENVIKONMtJtTAL 5EVK>b5. INC.
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site landfilling operations ceased in 1973, and a bituminous concrete pad was constructed in
the southwest portion of the landfill for staging of industrial materials and equipment.
At the time of the Initial Assessment Study (Envirodyne, 1982), 42 steel drums, 87
transformers (both mineral oil and polychlorinated biphenyl ["PCB"] filled), and 60 to 80
electric switches were stored on the bituminous concrete pad. Two transformers and several
electrical switches were leaking at that time. Past leakage of oil was also evident. Most
drums were stacked on wooden pallets. Drums with PCB labels were covered and bound
with plastic sheeting. All of these materials have been properly disposed off site. There are
no written records regarding storage of materials on the concrete pad. All available
information regarding use of the pad is based on the IAS survey and interviews with Subase
personnel, and has been provided herein.
In recent years, sand bags and contractor supplies and equipment have been stored
over the former landfill. Several transformers, crane weights, excavated underground
storage tanks ("USTs"), and other equipment were stored on the bituminous concrete pad in
the southwest portion of the landfill. The specific items stored in this area change over time.
A gravel-covered, long-term, vehicle parking lot (deployed parking) also exists on the former"
landfill.
B. Enforcement History
Previous investigations and the enforcement history of the Area A T-andfin are
summarized as follows:
Installation Restoration Program ("IRP"). 1975. In response to the growing
awareness of the potential effects of hazardous materials on human health and the
environment, the Department of Defense ("DOD") developed the IRP to investigate
and clean up potential problem areas created by past events at federal facilities. The
IRP was the catalyst for environmental investigations at the NSB-NLON. All
environmental investigations performed to date at Area A Landfill have been
conducted under the IRP.
Initial Assessment Study ("IAS"). Envirodvne Engineers. Inc. (Envirodvne).
1982. The purpose of the IAS was to identify and evaluate past hazardous waste
disposal practices at NSB-NLON and to assess the associated potential for
environmental contamination. Envirodyne recommended farther investigation and
testing of areas, including the Area A Landfill in the IAS report.
Verification Study. Wehran Engineering. Inc.. 1988. The purpose of the
Verification Study was to determine whether toxic and hazardous materials identified
in the IAS were present on site, and to further assess the potential impact of the
contamination on human health and the environment. The presence of hazardous
contaminants at Area A was confirmed during this study.
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NSB-NLON is Placed on the National Priorities List ("NPL") b\ the EPA. 1990.
Area A Landfill was included among the list of sites of concern.
Phase I Remedial Investigation ("RI") NSB-NLON. Atlantic Environmental
Services, Inc., 1992. Area A Landfill was identified as one of several NSB-NLON
sites posing potential risks to human health and the environment.
Draft Phase II RI NSB-NLON. HaUburton NUS. 1995. Work performed during
the Phase n RI addressed and filled data gaps from the Phase I RI and previous
investigations in order to further delineate the extent and degree of contamination.
Federal Facility Agreement ("FFA") for NSB-NLON. January 5. 1995. The
Navy entered into an FFA with EPA and the Connecticut Department of
Environmental Protection ("CTDEP") regarding the cleanup of environmental
contamination at NSB-NLON. The FFA establishes the roles and responsibilities of
each agency, sets deadlines for the investigation and cleanup of hazardous waste sites,
and establishes a mechanism for the resolution of disputes among the agencies.
Focused Feasibility Studv ("FFS"). Atlantic. Mav 26. 1995. The FFS offers
descriptions and evaluations of remedial alternatives considered for the Area A
Landfill. The FFS for Area A Landfill considered all relevant supplemental data from
the Draft Phase n RI hi the evaluation of risk and remedial alternatives.
Addendum to the FFS. Atlantic. Mav 31. 1995. The addendum to the FFS for the
Area A Landfill was prepared in response to United States Environmental Protection
Agency ("EPA") comments dated April 19, 1995 and May 8, 1995 regarding certain
design issues not addressed in the FFS for the Area A Landfill. Specifically, this
addendum addresses slope stability and leachate collection.
COMMUNITY PARTICIPATION
Throughout the history of the investigations and enforcement activities at NSB-
NLON, the community has been involved. The Navy has kept community members and
other interested parties aware of site activities through informational meetings, fact sheets
and information updates, press releases, public meetings, and Technical Review Committee
("TRC") and Restoration Advisory Board ("RAB") meetings.
The TRC was established in 1988 and was later (late 1994) reorganized and renamed
the RAB. The RAB (formerly TRC) has been an important vehicle for community
participation in the NSB-NLON IRP. The RAB consists of representatives of .the U.S. Navy,
EPA, CTDEP, planners and officials of neighboring towns, Navy and EPA contractors-, and
local residents with scientific knowledge of or interest in the sites. The RAB meets regularly
to review technical aspects of the NSB-NLON IRP and provides a mechanism for community
input to the program.
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To ensure that the community is well informed about NSB-NLON IRP activities, the
Navy has provided and will continue to provide the public with the following sources or
vehicles of information.
Public Information Repositories. The Public Libraries in Groton, Ledyard, and
the Naval Submarine Base are the designated information repositories for the Subase
IRP.
Kev Contact Persons. The Navy has designated a Public Affairs Officer ("PAO")
as an information contact for the Subase. The PAO maintains the site mailing list to
ensure that all interested individuals receive more pertinent information on the IRP
activities. Representatives from the Navy, EPA, and the Connecticut Department of
Environmental Protection attend all public meetings and hearings. Addresses and
phone numbers of key contact persons are included in all information materials
distributed to the public, including any fact sheets or press releases.
Mailing List. To ensure that information materials reach the individuals who are
interested in or affected by the IRP activities at the Subase, the Navy maintains and
will regularly update a mailing list of interested persons. Anyone interested in being
placed on the list can do so by contacting the Subase Public Affairs Officer.
Regular Contact With Local Officials. The Navy has managed and will continue
to arrange regular meetings to discuss the status of the IRP with the RAB, which
includes representatives from neighboring towns. The Navy contacts other town
officials on an as-needed basis.
Press Releases and Public Notices. The Navy has issued and will continue to
issue press releases to local media sources to announce public meetings and comment
periods, the availability of the IRP reports and plans, and to provide general
information updates.
Public Meetings. The Navy has held and will continue to hold informal public
meetings as needed to keep residents and town officials informed about IRP activities
at the Subase, and of significant milestones in the IRP. The meetings include
presentations by Navy technical staff, EPA personnel, and/or support contractors for
both agencies. The meetings also include a question-and-answer period. Minutes of
meetings during public comment periods are included in the Administrative Record
for public reference.
Fact Sheets and Information Updates. The Navy has been developing a series of
fact sheets which are mailed to public officials and other interested individuals and/or
used as handouts at the public meetings. Each fact sheet includes a schedule of
upcoming meetings and other site activities. The fact sheets may explain why the
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Navy is conducting certain activities or studies, update readers on potential health
risks, or provide general information on the ERP process.
A detailed formal NSB-NLON Community Relations Plan was published in February
of 1994. The plan identifies issues of community interest and concern regarding the NSB-
NLON. The plan also describes a program of community relations activities that the Navy
will conduct during the IRP.
The activities of the community relations program outlined in this plan have the
following specific objectives: (1) to keep local officials, citizens, military personnel, and the
media informed of site activities; (2) to increase community awareness of the goals and
procedures of the IRP; and (3) to provide opportunities for public involvement in the cleanup
process.
The information in the Community Relations Plan is based upon:
interviews with area residents and local officials conducted in Groton and Ledyard
on October 2-3, 1991;
interviews with area residents and local officials conducted by phone in September
and October of 1991;
input of the TRC or RAB which had regularly met to discuss progress at the
Subase;
public comments and questions at public information meetings held in 1990 and
1991;
review of Navy site files; and
discussions held with Navy, EPA, contractors, and technical and public affairs
staff.
The Navy held several meetings to inform the public about the Area A landfill
investigations, studies, and cleanup plans. These meeting occurred on November 9, 1994;
February 22, 1995; April 5, 1995; and May 18, 1995 in Groton, CT.
The public comment period on the Area A Landfill Proposed Plan ended on June 30,
1995. An informational meeting was held on June 7, 1995 and the public hearing was held
on June 28, 1995.
IV. SCOPE AND ROLE OF RESPONSE ACTION
The method chosen for remediation of soils at the Area A Landfill is the preferred
alternative selected from numerous cleanup alternatives examined for the site. The preferred
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alternative chosen for the Area A Landfill involves consrruciion of a low-permeability surface
cap. A low-permeability cap would be placed over an area of up to 13 acres where wastes
have been disposed, as shown in Figure 1-3. Depending upon the results of a pre-design
study, the area covered by die cap may vary from the current estimate of 13 acres. The cap
will consist of a bedding/gas management layer, a double liner, topped with a drainage layer,
and an operating surface (see Figure 4-1).
The low-permeability double liner will minimize water infiltration to the landfill. The
bedding/gas management layer will provide a protective bedding for the liner and act as a
conduit for any landfill gas which will be vented at appropriate locations. The drainage
layer, installed over the double liner, will remove water to prevent ponding above the liner.
The operating surface will protect the underlying cap layers from damage. This operating
surface will consist of an aggregate base course covered by an asphalt surface. The cap will
be graded to prevent run-on and promote runoff.
A groundwater interception system will be installed to collect shallow groundwater
flowing to the landfill and reroute it around the landfill to reduce contact of the groundwater
with landfill contents/soils. Existing storm drainage lines passing through the landfill will be*9"
plugged, and storm water will be rerouted around the landfill. All subsurface drains will be
constructed to prevent leachate from the landfill moving off of the site.
A leachate collection system may be installed to stabilize the cap and to further
contain landfill wastes. The system will isolate and collect the leachate for treatment and/or
disposal. Based upon the results of a pre-design study, the type of leachate collection system
that may be installed will be selected and the need for such a system will be determined
The pre-design study shall estimate the leachate generation rate and transport both before and
after the cap is installed. Construction of the cap shall not begin until such pre-design
studies are completed and EPA, the CTDEP, and the Navy agree upon the results.
After completion of the cap, NSB-NLON current operations, such as parking and
equipment storage, will be resumed on site. Access to the site will continue to be restricted
Via perimeter fencing and security procedures. Operation and maintenance, procedures
preventing any unauthorized digging or other activities that might jeopardize the cap's
integrity would be implemented. In addition, groundwater will be monitored after the
landfill is capped.
V. SUMMARY OF SITE CHARACTERISTICS
The nature and extent of soil and groundwater contamination detected at the Area A
Landfill are summarized herein. Complete discussions of the characteristics and
contaminants at the site can be found hi the Phase I and Draft Phase n RI Report (Atlantic,
August 1992 and Haliburton NUS Corp., February 1995, respectively) and the site FFS
(Atlantic Draft Final, March 15, 1995).. Note that the remedial actions described in this
ROD address soil contamination, and have not been designed for the remediation of
groundwater, although they may help improve groundwater quality at the site.
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V//////////777/;
P!O!O!O!O°OOOQOOP'
PLATEAU AREA FINAL COVER SYSTEM
BITUMINOUS CONCRETE SURFACE COURSE
BASE COURSE
WOVEN CEOTEXTILE
DRAINAGE LAYER/
SUBBASE
SMOOTH GEOMEMBRANt
GEOSYNTHETIC
CLAY UNER
- BEDOING/CAS
MANAGEMENT LAYER
/ / / / COMMON FILL OR / / / s
' "LANDFILL MATERIAL
/ / / / , , / , , , / / / /
SIDESLOPE AREA FINAL COVER SYSTEM
NON-WOVEN GEOTEXTiLE
DRAINAGE LAYER
TEXTURED GEOMEMBRANE
COHESIVE BACKFILL
NON-WOVEN G£OTEXTU£
BEDDING/GAS
MANAGEMENT LAYER
DEOSON SUMMARY
AREA "A" LAMJRLL
NAVAL SUBMARINE BASE - NEW LONDON
GROTON, CT
FIGURE 4-1
CAP DIAGRAM
ATLANTIC ENVKONMENTAL SERVICES. INC.
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The sources of contamination detected at the Area A Landfill are predominantly the
materials discarded at the landfill. Documented soil contaminants detected, based on
investigations performed to date, are summarized in Table 5-1 and include the following:
Volatile organic compounds ("VOCs"), predominantly toluene, ethylbenzene and
xylene, ranging in concentration from not detected to 75 pans per million ("ppm")
for individual constituents, and 93.5 ppm for total VOCs. Benzene was not detected.
Semivolatile organic compounds ("SVOCs"), predominantly polycyclic aromatic
hydrocarbons ("PAHs"), ranging in concentration from not detected to 61 ppm for
individual constituents, and 321 ppm for total PAHs.
Pesticides, predominantly DDT, DDD, and DDE, ranging in concentration from
not detected to 2.3 ppm for individual constituents, and 2.9 ppm for total constituents.
Polychlorinated biphenyls ("PCBs"), ranging in concentration from not detected to
130 ppm for total PCBs.
Inorganic constituents of concern (heavy metals), including beryllium, barium,
cadmium, copper, nickel, zinc, chromium, and lead.
The areas of soil contamination that present risks were adjacent to the bituminous
concrete pad area where PCBs were detected at concentrations of up to 130 ppm. The
location of this area of soil containing elevated levels of PCB is depicted in Figure 1-3.
As discussed in Section VI, remediation is necessary at the Area A Landfill because
of exceedances of several maximum contaminant levels ("MCLs") and historical records that
indicate the disposal of hazardous substances. Groundwater contaminants detected at the
Area A Landfill, are summarized in Table 5-2. Groundwater contamination will be evaluated
separately and incorporated as part of the final remedy. Placement of a RCRA C cap over
the Area A landfill will reduce contaminant leaching to groundwater.
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Table 5-1: Chemical Concentrations in Area A Landfill Soils
Constituents Exceeding "To Be Considered" Values in Soils
Constituent
' Arsenic
Barium
Cadmium
Lead
Selenium
DDTR
PCB
Concentration
Range
Detected (ppb)
ND to 300
146 to 1,060
ND to 65
ND to 2,190
ND to 230
ND to 2,470
ND to 130,000'
ND to SUOOO2
Number of
Values Above
TBC
8 of 14
1 of 14
9 of 14
5 of 14
5 of 14
4 of 31
6 of 57/9 of 57
2 of 31/3 of 31
TBC (ppb)
50 (in TCLP
extract)
1,000 (in TCLP
extract)
5 (in TCLP
extract)
15 (in TCLP
extract)
36 (in TCLP
extract).
500
10,000/2,000
10,000/2,000
Source of TBC
CTDEP Draft
Proposal for CT
Cleanup Standard
Regulations
CTDEP Draft
Proposal for CT
Cleanup Standard
Regulations
CTDEP Draft
Proposal for CT
Cleanup Standard
Regulations
CTDEP Draft
Proposal for CT
Cleanup Standard
Regulations
CTDEP Draft
Proposal for CT
Cleanup Standard
Regulations
FFDC Act
Tolerance Level
U.S. EPA
Regulations at 40
CFR Part 761/
CTDEP Guidance
22 Apr 94
'Field Screening Using Gas Chromatography
:Laboratory Analysis
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Table 5-2: Chemical Concentrations in Area A Landfill Groundwater
Constituents Exceeding MCLs or "To Be Considered" Values in Groundwater
Constituent
1,1.2,2-
Tetrachloroethane
Benzene
Chlorobenzene
Trichloroethene
1,4-
dichlorobenzene
Cadmium
Lead
Aluininuni
Iron
Manganese
Sodium
Concentration
Range
Detected (ppb)
ND to 140
ND to 10
ND to 220
ND to 10
ND to 99
ND to 44.8
ND to 22.4
ND to 2.060
28.1 to 192,000
2.3 to 8,130
9,020 to
1,360,000
Number of
Values
Above MCL
or TBC
2 of 20
Iof20
1 of 20
1 of 20
Iof20
6 of 20
Iof20
Iof20
15 of 20
17 of 20
12 of 20
MCL or
TBC
(ppb)
0.5
5
100
5
75
5
15
200
300
50
28,000
Source of MCL
or TBC
CTDEP GWPC
U.S. EPA MCL
CTDEP GWPC
U.S. EPA MCL
U.S. EPA MCL
U.S. EPA MCL
U.S. EPA Action
Level
Secondary MCL
Secondary MCL
U.S. EPA
Secondary MCL
CTDOHS
notification level
VI. SUMMARY OF SITE RISKS
A Risk Assessment was performed to estimate the probability and magnitude of
potential adverse human health and environmental effects from exposure to contaminants
associated with soils at the Area A Landfill. The public health risk assessment followed a
four step process: (1) contaminant identification, which identified those hazardous substances
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which, given the specifics of the site, 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; and (3) risk characterization,
which integrated the two earlier steps to summarize lie potential and actual non-carcinogenic
(toxic) and carcinogenic (cancer causing) risks posed by hazardous substances at the site.
The results of the public health risk assessment for the Area A Landfill are discussed below,
followed by the results of the ecological risk assessment.
Risk assessment is a tool used to determine the magnitude and probability of potential
harm to human health by exposure to toxic substances. In a risk assessment, the chemicals
of concern are identified, the rate of exposure to populations of concern are estimated, the
potential toxicological responses to various doses of the chemicals are determined, and the
potential risks of adverse health effects based on dose-response data and exposure data are
estimated. The resulting numbers represent a potential upper-bound likelihood of adverse
health effects.
Cancer risks are expressed in terms of predicted additional cases of cancer in an _
exposed population over a lifetime. For example, 2.7 additional cancer cases in 100,000
individuals would be expressed as 2.7 x 10~5. Superfund selects remedies that reduce the
threat from carcinogenic contaminants at each site such that the excess risk from any medium
to an individual exposed over a lifetime generally falls within a range from 1 in 10,000 (lO"4)
to 1 in 1,000,000 (10*).
Non-carcinogens are assumed to have a threshold below which health effects are not
initiated. This threshold, or reference dose, is the estimated highest average daily exposure
to humans over a lifetime unlikely to cause adverse health effects. Because the reference
dose reflects the acceptable dose below which no adverse health effects would be expected,
any observed dose below the reference dose would be considered acceptable. By comparing
the reference dose to the dose from a particular area, a Hazard Ratio can be calculated. If
the Hazard Ratio is less than one, the dose is considered safe. If the Hazard Ratio is one or
greater, then adverse health effects may be likely, with the likelihood increasing as the
Hazard Ratio increases. No non-cancer risks from exposure to the Area A landfill were
identified, as all hazard ratios were well below one.
As described in the following sections, however, all risks evaluated for exposure to
Area A landfill soils were acceptable. Remediation is necessary because of exceedanr.es of
several groundwater maximum contaminant levels ("MCLs"), and historical records that
indicate the disposal of hazardous substances. Remediation of groundwater will not be
addressed in this effort, but will be evaluated as part of the final remedy. Placement of a
RCRA C cap over the Area A landfill will reduce contaminant leaching to groundwater.
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Human Health
Contaminant Identification
The Area A Landfill is one of a number of sites under evaluation at NSB-NLON.
Because of the potential for cumulative risks associated with this site, a single base-wide list
of chemicals of concern was developed. This ensured that chemicals were consistently
evaluated from location to location even though some of the chemicals included on the list
may not have been detected at a particular location. The chemicals evaluated for this area
and the Navy Base in general are listed below.
Non-carcinogenic PAHs
(All TCL Compounds Included)
Other Semi-Volatiles
(12 compounds: primarily
phthalates and phenols)
BTEX Compounds
(All BTEX compounds: Benzene,
Toluene, Ethyl Benzene, Xylene)
Carcinogenic PAHs
(All TCL Compounds Included)
Pesticides
(7 compounds: DDT residues,
endrin, methoxychlor)
Chlorinated Volatiles
(13 compounds)
PCBs
(Aroclors 1260 & 1254)
Metals
(14 compounds: Al, Sb, As, Be,
B, Cd, Cu, Fe, Pb, Mn, Hg. Ni,
Se, Zn)
Other Volatiles
(4 compounds)
Exposure Assessment
Based on information obtained through site visits, inspections, and discussions with
personnel at the Area A Landfill or involved in future plans for the area, the following
potential receptors were identified:
utility workers repairing storm sewers in landfill;
weapons center personnel exposed to fugitive dust from landfill;
military servicemen moving palettes in Alpha A Storage;
military servicemen exposed to fugitive dust while engaging in nearby recreational
activities;
Groton/Ledyard residents exposed to fugitive dust;
citizens attending car auctions in Deployed Parking Area;
subase children exploring the Area A Landfill and surrounding woodlands; and
subase children playing in adjacent areas and exposed to fugitive dusts from Area
A Landfill.
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Risk Characterization
The results of the Risk Assessment for each scenario are tabulated as follows.
RISK SUMMARY TABLE
NAVAL SUBMARINE BASE, GROTON
.::.:. ..:: ....,:....,.,........,,..,...,............ _
...-.-. .-. .,;./.;.. . . .-. .?. - - Scenano
Utility Worker Repairing Storm Sewers in
Area A Landfill
Weapons Center Personnel Exposed to
Fugitive Dust From Area A i-aprnii
Military Servicemen Moving Paiezes
Within Area A Landfill
Military Servicemen Exposed to Fugitive
Dust While Engaging in Nearby
Recreational Activities
Groton/Ledyard Residents Exposed to
Fugitive Dust
Citizens Attending Car Auctions :j.
Deployed Parking
Subase Children Exploring the Area A
Landfill and Surrounding Woodlads
Subase Children Exposed to Fugiuve Dust
From the Area A Landfill
Total Cancer Risk
Average
1.80E-07
8.20E-08
9.20E-06
7.90E-10
1.50E-08
3.30E-07
3.06E-06
6.40E-11
Maximum
1.10E-06
2.60E-07
4.20E-05
1.60E-09
2.90E-08
5.80E-07
1.75E-05
1.40E-10
Total Hazard Indices
Average
2.40E-02
6.30E-04
1.30E-01
3.60E-05
3.10E-04
6.5E-03
7.0E-02
4.4E-06
Maximum
8.50E-02
1.50E-03
3.30E-01
5.40E-05
5.80E-04
l.OE-02
1.8E-01
l.OE-05
Utility Worker Repairing Storm Sewers in Area A Landfill
The Hazard Indices do not exceed unity for this scenario. The carcinogenic risks
were primarily due to the presence of PCBs in the subsurface soils and, to a lesser
extent, the presence of carcinogenic PAHs. The maximum total cancer risk is
approximately 10"6 risk. The distribution of the PCB and PAH contamination hi the
soil was patchy; therefore, the average risk is expected to be lower man that estimated
using the maximum values. Based on the results of the analysis, the risks to the
workers in this scenario are judged to be low.
Weapons Center Personnel Exposed to Fugitive Dust from Area A Landfill
The non-carcinogenic health risks and the carcinogenic risks are within levels
considered to be acceptable.
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Military Servicemen Moving Palleis within Area A Landfill
Non-carcinogenic health risks were negligible for these workers. Total cancer risks
exceeded the 1E-06 goal but are within the EPA acceptable range. The risk is
primarily due to the presence of PCBs in the landfill surface soils.
Military Servicemen Exposed to Fugitive Dust While Engaged in Recreational
Activities Near Area A Landfill
The non-carcinogenic health risks and the carcinogenic risks are negligible for
potential receptors in this scenario.
Groton/Ledyard Residents Exposed to Fugitive Dust from Area A Landfill
The non-carcinogenic health risks and the carcinogenic risks are negligible for
potential off-site receptors in this scenario.
Citizens Attending Car Auctions in Deployed Parking Area
The non-carcinogenic health risks and the carcinogenic risks are negligible for auction
participants in this scenario.
Subase Children Exploring the Area A Landfill and Surrounding Woodlands
Systemic (non-carcinogenic) health risks are negligible for this exposure group.
However, the total cancer risks were 1.75E-05 and exceeded 1 in 1,000,000 (1E-6).
The carcinogenic risk is due to the presence of PCB Arochlor 1260 through ingestion
and dermal contact with surface soils.
Subase Children Exposed to Fugitive Dust from the Area A Landfill
Systemic (non-carcinogenic) and cancer risks are estimated to be negligible via
exposure to fugitive dusts.
The human health risk assessment for the Area A T.-andfiU indicates thatt for the
scenarios considered, the risks to human h'Bdth from the landfill are minimal These
minimal risks are due primarily to the presence of PCBs in the landfill soils.
Ecological
Since the proposed remedial action is a containment presumptive remedy and only is
applicable to the capping of the landfill, the ecological risk discussion is limited. Placement
of a cap on the Area A landfill has Eliminate the need to evaluate ecological exposure
pathways resulting from direct contact of surface soils in the landfill to environmental
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receptors. Risk based PCB screening levels were developed for the wetland soils/sediment
sampled at the interface between Area A Landfill and Area A Wetland to ensure that elevated
PCB sediment concentrations would not result in an unacceptable risk to ecological receptors.
Any potential for ecological risk at downgradient (Area A Downstream) and adjacent
locations (Area A Wetland) involving migration from landfill contaminants will be evaluated
following the completion of subsequent investigations.
Contaminant Identification
The data evaluation and selection of compounds of interest for the ecological risk
assessment were the same as for the human health risk assessment described above.
Compounds of ecological concern were detected in soils and later sampled in wetland
sediments adjacent to the landfill.
Exposure Assessment
_.
Based on the presumptive remedy approach, the evaluation of exposure pathways
based on direct contact of surface soils to ecological receptors was not necessary. However,
wetland sediment samples were collected and analyzed for PCB concentrations at areas
adjacent to the landfill to assess the potential ecological risk to terrestrial vegetation and soil
invertebrates from landfill erosion.
Risk Characterization
Risks to terrestrial vegetation and soil invertebrates resulting from erosion of
contaminated surface soils from the Area A Landfill were estimated through application of
the equilibrium partitioning approach. The results indicated that the PCB concentrations in
sediments were lower than risk based screening levels. Therefore, ecological risks to benthic
invertebrates and terrestrial vegetation from erosion of contaminated soils from the Area A
Landfill were considered low. Some risk to benthic invertebrates was associated with
exposure to PAHs in two wetland soil samples, 2WMW5S and 2WSD9. Soil invertebrates
may occasionally be exposed to contaminants in groundwater discharge. However, risks to
these organisms from this source appear to be low because of the low contaminant
concentrations detected in the groundwater in this area. Erosion of contaminated surface
soils from the Area A Landfill to the adjacent wetlands present a continuing source of
contamination which could present risks to biota and plants in the wetland.
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VH. DEVELOPMENT AND SCREENING OF REMEDIAL ALTERNATIVES
A. Statutory Requirements/Response Objectives
The U.S. Navy is responsible for addressing environmental contamination at the Area
A Landfill pursuant to Section 120 of the Comprehensive Environmental Response,
Compensation, and Liability Act ("CERCLA") and the Federal Facility Agreement entered
into by the Navy, EPA, and the CTDEP. The Navy's primary responsibility under these
legal authorities 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: a requirement that the remedial action, when
complete, must comply with all federal and more stringent state environmental standards,
requirements, criteria or limitation, unless a waiver is invoked; a requirement that the
remedial action is cost-effective and uses permanent solutions and alternative treatment
technologies or resource recovery technologies to the marinrnm extent practicable; and a
preference for remedies that permanently and significantly reduce the volume, toxicity, or
mobility of the hazardous substances as a principal element over remedies not involving such
treatment. Response alternatives were developed to be consistent with these Congressional
mandates.
Based on preliminary information relating to types of contaminants, environmental
media of concern, and potential exposure pathways, remedial action objectives were
developed to aid in the development and screening of alternatives. These remedial action
objectives were developed to mitigate existing and future potential threats to public health
and the environment from contamination in the Area A landfill. These objectives are:
reduce exposure of persons and biota to contaminants within the landfill, in
particular regarding exposure of workers to PCBs in soils located near the bituminous
concrete pad; and
prevent erosion of and infiltration through landfill soils/contents.
The remedy selected is a presumptive remedy and is an interim remedy, as described
in the following paragraph.
Presumptive Remedies. Presumptive remedies are technologies preferred for use at
common categories of sites such as landfills. These technologies are preferred based on
historical information and data from site cleanups around the country. In reviewing remedy
selection at many sites, as well as currently available performance data on remedial
technologies, EPA has identified remedial actions that have been commonly selected for
particular types of sites and have performed well at those sites. Therefore, EPA has
determined what remedy or set of remedies are presumptively the most appropriate to address
specific types or categories of sites. EPA encourages presumptive remedies to be considered
at all appropriate sites. Presumptive remedies for landfills consist of containment remedies,
such as landfill caps, source area groundwater control to contain the plume, leachate
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collection and treatment, landfill gas collection and treatment, and/or institutional controls to
supplement engineering controls.
Inrerim Remedies. The remedial actions selected are intended to be final remedial
actions for only soils and landfill contents because the-cap will be the final cap and no
further excavation is expected to take place. However, the remedial actions are not final for
the Area A Landfill site as a whole because risks to the environment from contaminated
groundwater need to be evaluated after the source control remedies are completed. Based on
this assessment, a determination will be made whether on-site groundwater remediation
measures are necessary to protect water quality.
B. Technology and Alternative Development and Screening
CERCLA and the National Contingency Plan ("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 Area A Landfill as part of the FFS. Treatments that
reduce toxicity, mobility, or volume of the hazardous substances are principal elements of the"
alternatives. The alternatives developed included: alternatives that remove or destroy
hazardous substances to the maximum extent feasible; eliminating or minimi-Hna to the
degree possible the need for long-term management; alternatives that treat the principal
threats posed by the site but vary in the degree of treatment employed and the quantities and
characteristics of the treatment residuals and untreated waste that must be managed-
alternatives that involve little or no treatment but provide protection through engineering or
institutional controls; and no action alternatives.
Chapter 2.0 of the FFS for Area A Landfill discusses the identification, assessment,
and screening of technologies based on implementability, effectiveness, and cost. Chapter
3.0 of the FFS presents 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.
The alternatives for the site were then evaluated and screened in detail as described in
Chapter 4.0 of the FFS. In summary, of the remedial alternatives screened in Chapter 3.0,
only four alternatives for each site were retained for detailed and comparative analysis.
Section VET of this ROD and Appendix B present the alternatives and associated process
options that were considered and the alternatives retained for detailed and comparative
analysis. In addition, an addendum to the FFS was prepared which describes leachate
collection and treatment alternatives.
CRIPTION OF ALTERNATIVES
This section provides a summary of each alternative considered for the Area A
Landfill. In the FFS, eight alternatives were evaluated and four of those alternatives were
retained for further analysis. Detailed descriptions of these alternatives can be found hi
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Sections 3.3 and 4.0 of the FFS. This section summarizes the four alternatives retained for
further analysis and is summarized in a table in Appendix B.
Alternative 2L-1: No Action Analysis of the no-action alternative is required by
federal law and is included for comparison with other alternatives. A no-action alternative is
developed for each Superfund site to assess the impact on public health and the environment
if no measures are taken to correct current site conditions. The no-action alternative would
only be used if the site posed little or no risk to public health and the environment
The no-action alternative for the Area A Landfill would consist of taking no action to
either contain, treat, or otherwise minimize risk. In addition, no long-term maintenance,
monitoring, or institutional controls would be implemented at the site.
Estimated Time for Construction: No construction .
Estimated Total Cost: 0
Alternative 2L-3: Capping This alternative consists of grading the site to promote r
runoff and prevent run-on and the installation of storm water management systems. A low-
permeability cap would then be installed over all areas of the site where wastes have been
disposed, as shown in Figure 1-3. Depending upon the results of a pre-design study, the
area covered by the cap may vary from the current estimate of 13 acres. The cap would
consist of a bedding/gas management layer, a double liner, topped with a drainage layer, and
an operating surface (see Figure 4-1).
The low-permeability double liner would prevent water infiltration to the landfill,
The bedding/gas management layer will provide a protective bedding for the liner and a
conduit for any landfill gas which will be vented at appropriate locations. The drainage
layer, installed over the double liner, would remove water to prevent ponding above the
liner, and the operating surface would protect the underlying cap layers from damage. This
operating surface will consist of an aggregate base covered by an asphalt surface. The cap
will be graded to. prevent run-on and promote runoff.
A groundwater interception system will be installed to collect shallow groundwater
flowing to the landfill and reroute it around the landfill to reduce contact of the groundwater
with landfill contents/soils. Existing storm drainage lines passing through the landfill would
be plugged, and storm water would be rerouted around the landfill. All subsurface drains
would be constructed to prevent leachate from the landfill moving offsite.
A leachate collection system may be installed to stabilize the cap and to further
contain landfill wastes. The system will isolate and collect the leachate for treatment and/or
disposal. Based upon the results of a pre-design study, the type of leachate collection system
that may be installed will be selected and the need for such a system will be determined
The pre-design study shall estimate the leachate generation rate .and transport both before and
after the cap is installed. Construction of the cap shall not begin until such pre-design
studies are completed and EPA, the CTDEP, and the Navy agree upon the results.
The Navy will develop operations and maintenance procedures mat restrict digging or
other activities that could jeopardize the integrity of the cap. Access to the site would be
controlled by continued maintenance of the existing perimeter fence and security procedures.
22
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The institutional controls would provide notice of hazardous materials on site and limit usage
of the property to reduce risks to human health and the environment. Perimeter fencing
would include existing fencing and some additional fencing around the area of elevated
PCBs. NSB-NLON personnel would be allowed to access the site. A groundwater
monitoring program would be implemented to monitor groundwater quality after closure of
the landfill is complete.
Estimated Time for Construction: 13 months
Estimated Capital Cost: $3,910,869
Estimated Operation and Maintenance Cost: $1,823,818
Estimated Total Cost: $5,734,687
Alternative 2L-4: Off-Site Incineration of the PCS Contaminated Soils and
Capping Under this alternative, all surficial soils containing PCBs greater than 10 ppm and
all deeper, accessible soils (to a depth of 10 feet) containing PCBs greater than 50 ppm
would be excavated. These areas, totaling approximately 300 cubic yards, are located near
the bituminous concrete pad.
After completion of the initial excavation, soil samples would be taken and analyzed
to confirm that target cleanup levels were met. If not, excavation would continue until
samples confirm that target cleanup levels were met or until a depth of 10 feet is reached.
The removed materials would be transported off site for treatment by incineration at a
facility permitted to manage PCBs. The treated soils (incinerated) would then be disposed in
a secure chemical landfill used by the incineration facility for ash disposal.
After contaminated soil removal, a low-permeability cap would be installed. The cap,
associated runon and runoff controls, and leachate collection systems are the same as those
described for Alternative 2L-3 (capping).
Operations and maintenance procedures would be developed to prevent/restrict any
digging or other activities that could jeopardize the integrity of the cap. Access to the site
would be controlled by continued maintenance of the existing perimeter fence and security
procedures. Institutional controls, as described for Alternative 2L-3 (Capping), would also
apply. In addition, a groundwater monitoring program would be instituted to monitor
groundwater quality after closure of the landfill.
Estimated Time for Construction: Less than 14 months
Estimated Capital Cost: $4,409,300
Estimated Operation and Maintenance Cost: $1,823,818
Estimated Total Cost: $6,233,118
Alternative 2L-5: Off-Site Disposal of PCB Contaminated Soils at a Hazardous
Waste Landfill and Capping Under this alternative, all surface soil containing PCBs
greater than 10 ppm and deeper accessible soils (up to 10 feet) containing PCBs greater than
50 ppm would be removed and disposed at an off-site landfill permitted to manage PCBs.
Accessible soils are defined as those soils that a person could potentially be exposed to, from
23
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the ground surface to a depth of 10 feet. These areas, totaling about 300 cubic yards, are
located adjacent to the bituminous concrete pad.
After completion of the initial excavation, soil samples would be taken and analyzed
to confirm that target cleanup levels were met. If target levels are not met in any area
sampled, excavation would be continued until excavation samples confirm that target cleanup
levels were met (to a maximum depth of 10 feet).
After contaminated soil removal, a low-permeability cap would be installed. The cap,
associated runon and runoff controls, and leachate collection system are the same as those
described for Alternative 2L-3 (capping).
Operation and maintenance procedures would be developed to prevent any
unauthorized digging or other activities that could jeopardize cap integrity. Access to the site
would be controlled by continued maintenance of the existing perimeter fence and security
procedures. Institutional controls as described in Alternative 2L-3 (Capping) would also
apply. In addition, a groundwater monitoring program would be instituted to monitor
groundwater quality after closure of the landfill.
Estimated Time for Construction: Less than 13 months
Estimated Capital Cos:: $4,127,300
Estimated Operation and Maintenance Cost: SI, 823,818
Estimated Total Cost: 35,951,118
THE COMPARATIVE
Section 121(b)(l) of CERCLA establishes several factors that, at a minimum EPA is
required to consider in its assessment of alternatives. Building upon these specific mandates
the NCP specifies nine evaluation criteria to be used in assessing the individual remedial
alternatives.
To select a site remedy, a detailed analysis was performed on the alternatives using
the nine evaluation criteria. The remainder of this section is a summary of the comparison
of each alternatives' strength and weakness with respect to the nine evaluation criteria.
These criteria are summarized as follows:
Threshold Criteria
The two threshold criteria described herein must be met in order for the alternatives
to be eligible for selection in accordance with the NCP.
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, engineering
controls, or institutional controls.
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Compliance with applicable or relevant and appropriate requirements ("ARARs")
addresses whether or not a remedy will meet all of the ARARs of other federal and
state environmental laws and/or provide grounds for invoking a waiver.
Primary Balancing Criteria
The following five criteria are used to compare and evaluate the elements of one
alternative to another that meet the threshold criteria.
Long-term effectiveness and permanence addresses the criteria that are utilized to
assess alternatives for long-term effectiveness and permanence they afford, along with
the degree of certainty of success.
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.
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.
Implementability addresses the technical and administrative feasibility of a remedy.
including the availability of materials and services needed to implement a particular
option.
Cost includes estimated costs of capital, and Operation and Maintenance ("O&M"),
as well as present worth costs.
Modifying Criteria
The modifying criteria are used on the final evaluation of remedial alternatives,
generally after EPA has received public comment on the RI/FS and Proposed Plan.
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.
Community acceptance addresses the public's general response to the alternatives
described in the Proposed Plan 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 can be found in Appendix B.
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The responsiveness of each alternative to the nine criteria was evaluated, and, based
on comparative analysis of the results, a preferred alternative was selected for the site. The
Capping Alternative was the preferred alternative selected for the Area A Landfill
(Alternative 2L-3).
A brief summary of the nine criteria and the strengths and weaknesses of each
alternative subjected to the detailed and comparative analysis is provided below.
Overall Protection of Human Health and the iSnvironment
The No Action Alternative (2L-1) provides no change in risk to human health and the
environment. Capping (Alternative 2L-3), Off-Site Incineration of PCB Contaminated Soils
and Capping (Alternative 2L-4), and Off-Site Disposal of PCB Contaminated Soils at a
Hazardous Waste Landfill and Capping (Alternative 2L-5) would eliminate risks due to direct
contact, ingestion and inhalation, and would prevent erosion and infiltration. Alternatives
2L-4 and 2L-5 would additionally reduce some on-site contamination via removal of PCB-
contaminated soil, and thereby reduce risks for utility/construction workers who may work "~
on site in the future, however such future work is unlikely.
Compliance With ARARs
The No Action (2L-1) Alternative would not meet federal and state RCRA hazardous
waste disposal area closure standards. The remaining three alternatives meet all ARARs.
Long-Tenn Effectiveness and Permanence
The No Action Alternative would not reduce or control potential risks in the Area A
Landfill. Alternatives 2L-3, 2L-4, and 2L-5 eliminate risks from direct contact with
contaminants. Although capping does not reduce risks to future utility/construction workers
since PCB contaminated soUs will remain in place under this alternative, these risks would be
eliminated through procedural means. Alternatives 2L-4 and 2L-5 offer a permanent risk
reduction since there is a net reduction in on-site PCB contamination.
Reduction of Toricitv. Mobility, or
The No Action Alternative (2L-1) offers no reduction in toxicity, mobility, or
volume. Capping (2L-3) does not reduce toxicity or volume but will reduce human contact
and the mobility of contaminants by reducing infiltration, erosion, and exposure to wind.
Alternatives 2L-4 and 2L-5 would reduce the toxicity and volume of on-site soil
contamination via removal of PCB-contaminated soil and would also reduce (via capping) the
mobility of contaminants by reducing infiltration. The Alternative 2L-5, however, would not
result in a net reduction in toxicity or volume since the PCB contaminated soil removed
would be landfilled offsite. However, mobility would be prevented at the off-site landfill).
Off-Site Incineration would cause a net reduction in volume, toxicity, and mobility since the
contaminants in the removed soils would be destroyed via incineration.
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Short-Term Effectiveness
The No Action Alternative (2L-1) does not increase protection of human health or the
environment. No remedial activities are undertaken under this alternative, and therefore,
risks to the community are not decreased due to remedial actions. However, the potential for
off-site migration of contaminants remains.
The Capping, Offsite Incineration, and Offsite Hazardous Waste Landfill Alternatives
all can be implemented within 12 to 14 months and would reduce the potential for human and
environmental exposure to the contaminants when completed. The remedial activities that
would be undertaken during implementation of any of these alternatives would create the
potential for windblown contaminated dust during excavation and grading activities.
Windblown dust can be nunirnized, however, via the use of dust suppression techniques.
Protection from exposure to contamination from contact can be minimised by appropriate
health and safety procedures. Under the capping alternative, there is no off-site
transportation of waste materials and, therefore, associated transportation risks, are small. _
Implementabilitv
The No Action Alternative is the easiest to implement since there are no activities,
approvals, services, or materials required.
All required services and materials are readily available for implementation of the
Capping, Offsite Incineration, and Offsite Hazardous Waste Landfill, Alternatives.
Coordination with regulatory agencies would be required to ensure that cap and closure
specifications meet ARARs, and that groundwater discharge and other impacts to wetlands
meet substantive requirements. Approvals would be required for disposition of contaminated
soil in the Off-Site Incinerator and Hazardous Waste Landfill Alternatives.
Costs
The total cost estimated for each alternative is:
No Action: $0
Capping: $5,734,687
Off-Site Landfill: $5,951,118
Off-Site Incineration: $6,233,118
State Acceptance
The Connecticut Department of Environmental Protection ("CTDEP") concurs with '
the preferred remedy. The CTDEP's letter of concurrence is included in Appendix D.
Community Accentance
27
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During the public comment period on the Proposed Plan and at the public hearing on
June 27, 1995 no objections were voiced from the community. In fact, the only comment
received praised the Navy's openness with the public and environmental progress at the site.
X. THE SELECTED REMEDY
The selected remedial alternative for Area A Landfill is Alternative 2L-3 (Capping).
This remedy involves grading and installation of an impervious cap over contaminated areas
of the site. The cap will form a barrier, reducing human and environmental exposure to site
contaminants. The cap will also reduce migration of contaminants from the site by
preventing exposure of contaminated soils from wind and erosive elements, and by
preventing infiltration of rain water through contaminated areas of the unsarurated zone.
A. Description of Remedial Components
The Navy's selected alternative for Area A Landfill, Alternative 2L-3 (Capping), is *"
desianed to substantially reduce human and environmental exposure to site contaminants and
to reduce the potential for the off-site migration of contaminants. The alternative includes
the following components.
Access Restrictions
Site Grading and Storm Water Management
Horizontal Barrier Cap Installation
Leachate Collection and Treatment
Post-Closure Groundwater Monitoring
Access Restrictions
Access to contaminated areas of the site will be limited via perimeter fencing and
institutional controls. Access will be limited to workers and other persons having business in
these areas.
Access dyiring the implementation of remedial measures will be limited strictly to
remedial workers, support personnel, and regulatory authorities. Use restrictions, directed at
preserving the integrity of the cap, will be enforced after remedial measures are completed.
The institutional controls would provide notice of hazardous matgrfcis at die site, and ensure
maintenance of cap integrity, worker protection, and other considerations.
Site Grading and Storm Water
As part of the process for installation of the cap, the site will be graded to promote
runoff and prevent run-on. In addition, a groundwater interception system will be installed
to collect shallow groundwater flowing to the landfill and reroute it around the landfill to
reduce contact of the groundwater with landfill contents/soils.
28
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Horizontal Barrier Cap Installation
After grading, a low-permeability cap will be installed over contaminated areas of
Area A Landfill, covering approximately 13 acres. The primary benefits of capping are the
elimination of human contact with contaminated materials and the elimination of direct
infiltration of storm water through the contaminated soils.
After completion of the cap, operations will resume at Area A Landfill (i.e., non-
landfill operations such as storage and deployed parking). Access will continue to be
restricted via the perimeter fence.
Leachate Collection and Treatment
A leachate collection system may be installed to stabilize the cap and to further
contain landfill wastes. The system will isolate and collect the leachate for treatment and/or
disposal. Based upon the results of a pre-design study, the type of leachate collection system
that may be installed will be selected and the need for such a system will be determined.
The pre-design study shall estimate the leachate generation rate and transport both before and
after the cap is installed. Construction of the cap shall not begin until such pre-design
studies are completed and EPA. the CTDEP. and the Navy agree upon the results.
Post-Closure Groundwater Monitoring
Groundwater will be monitored after the cap is installed. Depending upon the results
of this monitoring, groundwater remediation may be necessary. If groundwater remediation
is necessary, it will be addressed in the final remedy for this site.
XI. STATUTORY DETERMINATIONS
The remedial actions for implementation at the NSB-NLON Area A Landfill sites are
consistent with CERCLA and the NCP, to the extent practicable. The selected remedy is
protective of human health and the environment, attains ARARs, and is cost effective. The
remedy also significantly reduces the mobility, toxicity, or volume of hazardous substances
as a principal element.
A. The Selected Remedy is Protective of Human Health and the Environment
The remedy selected for implementation at the Area A Landfill will substantially
reduce the risks posed to human health and the environment by reducing or controlling
exposures to human and environmental receptors through engineering and institutional
controls. Cap placement over contaminated areas will reduce mobility of contamination and
eliminate human contact with contaminant*; The cap will also prevent direct storm water
infiltration through the contaminated soils. Moreover, the selected remedy will achieve
potential human health risk levels that attain the KF4 to 10"6 incremental cancer risk range and
29
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a level protective of noncarcinogenic endpoints, and will comply with ARARs and to-be-
considered ("TEC") criteria. Implementation of the selected remedy will not pose
unacceptable short-term or negative cross-media impacts.
B. The Selected Remedy Attains ARARs
The remedy will attain all applicable or relevant and appropriate federal and state
ARARs that apply to the site. All federal and state TBCs have been considered hi the
selection of the final remedy. ARARs identified for the selected remedial action include:
Chemical-Specific ARARs:
- CTDEP Water Pollution Control Regulations
- CTDEP Water Quality Standards
Location-Specific ARARs:
- Federal Clean Water Act, Section 404 Dredge and Fill Activities
- Federal Executive Order 11900 Regarding Protection of Wetlands
- CTDEP Inland Wetlands and Watercourses Regulations
Action-Specific ARARs:
- Federal RCRA Hazardous Waste Regulations (40 CFR Pan 264)
General Requirements (Subpart A)
Preparedness and Prevention (Subpart C)
Contingency Plan and Emergency Procedures (Subpart D)
Releases from Solid Waste Management Units (Subpart F)
Closure and Post-Closure Requirements (Subpart G)
- Federal Clean Air Act National Emission Standards for Hazardous Air
Pollutants ("NESHAPS")
- Federal National Pollution Discharge Elimination System ("NPDES")
- Federal PCB Regulations Under Toxic Substances Control Act ("TSCA")
- CJTIJKP Hazardous Waste Management Regulations
Generator and Handler Requirements General Standards, Listing,
and Identification
Generator Standards
TSDF Standards
Interim Status Facilities and Groundwater Monitoring Requirements,
Closure, and Post-Closure Requirements
Solid Waste Management Regulations
- CTDEP Regulations for Transportation of Oils and Chemical Liquids
- CTDEP Regulations for the Control of Noise
- State Air Pollution Control Regulations
30
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Control of Organic Compound Emissions
Control of Odors
Control of Hazardous Air Pollutants
Control of Paniculate Emissions
Stationary Sources
Sulfur Compound Emissions
Tables summarizing the detailed analysis of ARARs for Area A Landfill and
discussions of why the requirements were determined to be applicable or relevant and
appropriate were provided in Section 5.0 of the FFS. ARAR summary tables pertaining to
the selected remedy for the site are provided in Appendix C of this ROD. The applicability
(or non-applicability) of each ARAR is explained in the summary table.
The following policies, criteria, and guidances were also considered ("TBCs"):
Chemical-Specific:
- Federal EPA Human Health Assessment Can^r Slope Factors
- Federal EPA Reference Doses
- Proposed Connecticut Cleanup Standard Regulations
Location-Specific:
- State Inland Wetlands and Watercourses Acr General Requirements
Action-Specific:
- Federal EPA Technical Guidance Final Covers on Hazardous Waste
Landfill and Surface Impoundments
- Federal Clean Air Act Non-methane Organic Compounds ("NMOCs") -
(Proposed Rule - 56 FR 24468)
All federal and state chemical-specific ARARs and TBCs were used in the screening
of data from the site to help identify potential concerns. The use of chemical-specific
ARARs and TBCs in establishing remedial action objectives is described in subsection 3.2 of
the FFS for the site. ARARs and TBCs were also considered during the detailed evaluations
of alternatives (Section 5.0 of the FFS). ARARs were also considered in the comparative
analysis of alternatives (Section 6.6 of the FFS) and summarized herein in Section TX.
C. The Selected Remedial Actions Are Cost-Effecrive
In the Navy's judgment, the selected remedy is cost effective, i.e., the remedy affords
overall effectiveness proportional to cost. In selecting the remedy, the Navy identified
alternatives that are protective of human health and the environment and that again ARARs,
and evaluated the overall effectiveness of each alternative by assessing hi combination the
relevant three criteria: (1) long-term effectiveness and permanence; (2) reduction of toxicity,
mobility, or volume through treatment; and (3) short-term effectiveness.
31
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The relationship of overall effectiveness of the remedial alternative was determined to
be proportional to its cost. The cost of the remedial alternative is:
Estimated Capital Cost: $3,919,869
Estimated Operar.on and Maintenance Cost: $2,823,818
Estimated Total Cost: 55,734,687
The selected alternative offers a net improvement in conditions at the site that is
comparable or better than the other alternatives investigated and at the lowest cost of any
alternative offering the same level of improvement.
Of the four alternatives retained for comparative analysis, the No Action (therefore no
cost) Alternative was the least expensive, but offered no protection to human health or the
environment. Off-Site Incineration of PCS Contaminated Soils (and Capping) was the most
expensive alternative, with an estimated cost of $6,233,118, and was approximately 10
percent more expensive than the cost of the selected alternative. Alternative 2L-5, Disposal
of PCB Contaminated Soils at an Offsite Landfill and Capping, was slightly more expensive
than me selected alternative. The selected alternative. Capping, was estimated to be
55.734,687. It was determined that the Capping Alternative was the most cost effective
since it could achieve the same level of reduction in human and environmental exposure as
the Off-Site Incineration and Off-Site Landfill Alternatives, at a lower cost. A detailed cost
estimate for implementation of the Capping Alternative for Area A Landfill is provided in
Table 11-1 .and Table 11-2.
D. The Selected Remedies Utilize Permanent Solutions and Alternative
Treatment or Resource Recovery Technologies to the Maximum Extent
Practicable
The Navy identified those alternatives that attain ARARs and are protective of human
health and the environment. Trie Navy also identified which alternatives utilize permanent
solutions and alternative treatment technologies or resource recovery technologies to the
maximum extent practicable. This determination was made by deciding which of the
identified alternatives for each site 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 tests considered: long-term effectiveness and permanence and the reduction of
toxicity, mobility, and volume through treatment; the preference for treatment as a principal
element; the bias against off-site land disposal of untreated wastes; and community and state
acceptance. The selected remedy provides the best balance of trade-offs among the
alternatives. The net on-she effect of the Capping Alternative in reducing pollutant mobility,
the potential for human/environmental toxic exposures, and the associated long-term
effectiveness and permanence, is virtually equivalent to, or better than, any of the
32
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iNritrvAmAiu.t.sMssuMrnoNS ': .
DJKounl Rile (11) - Id1.'.
Average 1 of yeaiaOA M 10
Total volume Inilru toil (cjr) * 300
Total volume water (gal) 0
Dcnilly of aoil (lon/cy) - 1 . 10
Avg conceitliatliin of rclidiial (%) !'/'
Moinute of toll (/.) - 15%
* of recovery wclll 0
average pumping rale per well (gpm) - 0
lurfacc area of contaminated loil (if) 566280
CATEOOHV/UESCRIPTION :
St.imUtlMKNI
Limited iciioit icctii letiricilon
Conttinmcnl * horizontil barrier
Containment luiface wiler conirol
Rctnovit eicavailon, (frcJiifiif
Submitter ildinige trench
On venting ucnch
Ground wa let monitoring
WATER
Limited action - no action, icccis rcitHciIon
Conlitnmenl - ftoumj water control, horiionul binicr
veitlcil burier
Removal - lubiurfacc drilni, pumping
Iniltu Treitincnl - blologlcil. phyiluuchemicil
Above giounJ Treatment biological, phyifcil/chemleit
llicnntl
Olipoiif onnle/orTiilo
INI triMkUiA it:
Keitduil treiimeni/biipotif omlie/oifitic
biological, phyitcat/chemical, therm il
Dewitciing flhci preii, centrifuge,
di)lng bed, pumping
I nicking onillc. offiilc
Oniiic containment (wiiicwiier/niil) -
lagoon, modu-iank, eq link, beim, linci
Did fill piocure, place
SUBTOTAL I
oiiiKH ~ "
Site I'rtp oflice. ulijiitei
Mob/Dnnob pioccn equipment.
Mob/Demob * conitntcllon equipment, workcri
rrciUbilily itudy
Site Reitoi nlon * grading, aeeding
Other - health A ufciy, decon. project management.
t imp ting A telling, travel A expenses
SUBTOTAL 1
.. --- - .- : ..-..: ;.:-. .y:: - : .--. .;;-. ;.-..
Unglnccrfng Admlntilrailon
Contlngenclei
OfounJwuer C'oilcciion and btipoiiffice fable II ) for dciiilij
TOTAL
' .- - ' . - : ' - : : " .: : : ' '- >::;':-:- . .V:' >:. -:': : :'; :':- : ':-: ;:
TAIU.E 11-1
1)1,1 All.l.l) Ai;i'ICKNATIVK COST ESTIMATE
AllEA A LANDFILL - CONTAMINATED SOILS
ALTERNATIVE 2L-3, CAP
COSIHENTs -.-
iitcdicittfciton
Fencing
Suffice cap
Site g^ridin^ and ilonnwalcr niinujtinenl
,:. : -.:.; . :;:. ' .;. v: : : . :..-.; . -.: . ..;.
.:':":-: : :.:. ;:..:.;. .;. ' ::; ># . lo:'
- --.-.-.. -.--:.. . . . -..
ConiittioflSOcj
iofaciliaic liie grading
":':: .:- * : ::'- :.v:-:.' .- . ' . :' :-."
:" ' :. :.:-
0
"0
^of lubToial i
'/Tot luSiolal i
0
V. of lubloul I
0 */i of lublolil I
io
% of Subtotal!
1$ */. of Subtotal)
:'.":' ::' .:':
"QlRfffifT"
CAr
*:.. "..:;. .
i
0
566180
2600
.jr.-.:.:-.'::..:;-:...:;-
1100
':'.: .::.;:.; :..::! :':.
156
I.S
LF
... ........
I.F
. -. . -
I.F
LF
:. :.:<-:::
cy
ITAI. COSTS
1: UNIT COST .-
. : TOTAI,
. '
1666
"li
J.5
60
40
15
:..:;'::: -..'. yf-y
10
JI.OOO
to
tl.9tl.9IO
$156.000
SO
..::..':: ;::.:
ili.ooo
$)),)T5
ii
i:V:..>:;-'S.»-:: :'':'.
SO
so
to
so
... - -:., - .-.
"16
so
io
so
so
so
so
Sl.iOO
so
11,245.155
: .: . ::: .:'.?
' . -. . ; .- ::
\
.--.- :.:;'. ';::.
1
...'.
LS
US
:- v: -':. ' -.:;:.
1000
10000
: '..
*
TOTAL COST USTIMATG OF THIS AI.TGRNATIVU INCLUDING CAPITAL AND O&M COSTS
to
10
SI. 000
so
so
":: .:;.;.- :::-. :
S 10,000
I1.J66.IJ1
S116.6I6
t)40.0JI
tl.OO.loi
Ii.9l6.469
UPErLAllUNA MAINIENANCKCUSIK
QllAIYT/VR
1500
966110
1600
:.' .-- := :'.':.
1
- ': :. ,:.-
- :-_ -.;.-
. . :
- - -.- -v> :';:': :
UNITS
LF
SF
LF
LS
UNIT COST
1.1000
0.0115
0)000
liiood.M
.. -. ..- .. -
:
YBS
)0
JO
)o
)6
15
10
JO
16
io
JO
to
JO
)0
" 55
Io
JO
Jo
55
JO
55
JO
: :fW TOTAL '
' to
SJJ.II7
»7l.»07
si.in
so
so
so
SI, JO). 164
SO
SO
SO
SO
so
SO
so
so
so
so
so
so
so
$I,4I9.I9J
..V:1
':."" :
; '.':*:;:
:-. ':'::::.!' '
.. .:::. i;- '
:;.'.J:;:..:X"..
;
JI.4I9.I91
SI4I.9I9
til 1.179
i49,iii
SI, 12), III
.;: :::: :::::.. ..:; .-.
IS&SD
-------
Table 11 -2
Preliminary Cost Estimates
Area A Landfill
Vortical Containment and Loachato/Groundwator
Collected and Disposed
Process Option
Slurry walls CAP
Sheet pile walls CAP
Interceptor Trenches CAP
O&M
Dewatering wells CAP
O&M
POTW CAP
O&M
On-slte treatment CAP
O&M
Engineering & cont. CAP 33%
O&M 33%
Quantity
50000
50000
2100
1
7
1
1
5475
1
5475
Units
SF
SF
LF
LS
EACH
LS
LS
TGPY
EACH
TGPY
Unit Cost
$10.00
$25.00
$100.00
$525.00
$10,00000
$350.00
$20.000.00
$0.05
$100.000.00
$0.03
CAPITOL TOTAL:
O&M TOTAL:
GRAND TOTAL:
CAP - capital cost
O&M - operation and maintenance cost. Present value.
SF - square feet
LF - linear foot (IJsFV
LS - lump sum
TGPY - thousand gallons per year
ALT. 1a
$500,000
$210.000
$4,949
$20,000
$2,501
$240.900
$2,485
$970,900
$10.015
$980,915
ALT.2a
$500,000
; $210.000
$4,949
$100,000
__ $32,516
5 $267,300
$12.383
$1,077,300
$49,828
$1.127il28
ALT. 3a
$500,000
$70.000
$3,299
$20,000
$2.581
$194,700
$1,940
$784,700
$7,820
$792.620
ALT. 4a
$500,000
$70,000
$3,299
$100.000
$32,516
$221,100
$11.819
$891.100
$47,634
$938.734
Shading Indicates cost selected for cost estimates in proposed plan.
-------
alternatives evaluated for both sites. The short-term risks posed during implementation of
the Capping remedy are easily controllable, and the short-term benefits are immediately
equivalent to the long-term benefits once the remedial action is completed. Though treatment
is not utilized in this alternative and there is no net reduction in the volume or the toxicity of
contaminated soils, this alternative effectively prevents their mobility and availability of toxic
characteristics.
The Capping Alternative is readily implementable at the site since all required
materials and services are available and can be procured within a reasonable period. This
alternative offers the greatest net improvement in conditions at the site at the lowest cost of
any alternative offering the same general level of improvement.
E. The Selected Remedy Significantly Reduces the Toxicitv, Mobility, or Volume
of the Hazardous Substances as a Principal Element
The principal elements of the selected remedy are the management of migration of,
and prevention of human and environmental exposure to, soil contamination present at Area ~
A Landfill. This element addresses the primary threat at the site and contamination of
potential worker exposure to contaminants in soils at the sites. Capping of the Area A
Landfill will significantly reduce the mobility of. and potential for exposure to, toxic
constituents in the soils.
XII. DOCUMENTATION OF NO SIGNIFICANT CHANGES
The Navy presented a proposed plan for the remediation of Area A Landfill on May
31, 1995. Based on a detailed analysis of factors at the site and available remedial
alternatives, the Navy proposed the following remedial plan for the site.
The site will be graded to promote runoff and prevent run-on, a low-permeability cap
will be placed over contaminated portions of the site, and a leachate collection system may
be installed if the results of a pre-design study indicate that one is necessary. The pre-design
study shall estimate the leachate generation rate and transport both before and after the cap is
installed. The cap will consist of a bedding/gas management layer overlain with a
geosynthetic clay liner and a geomembrane, a drainage layer, a woven geotextile, an
aggregate base and an asphalt surface. Access to the sites would be controlled by perimeter
fencing and security procedures. Although the cap would be designed to allow resumption of
current operations at the site, proper maintenance of the cap and fences would be required to
ensure long-term integrity. The Navy will develop institutional controls and operation
procedures to prevent/control digging or other activities that could jeopardize the integrity of
the cap.
The final remedy selected, as described hi this document, does not differ significantly
from the proposed plan. Although a few of the cap components described in the proposed
plan differ somewhat, these variations are not substantial. Cap design issues were also
discussed at the public informational meeting held on June 7, 1995.
-------
XHI. STATE ROLE
The CTDEP has reviewed the various alternatives considered for each site and has
indicated its support for the selected remedies. The CTDEP has also reviewed the Remedial
Investigations, Risk Assessments, and Feasibility Studies for each site to determine if the
selected remedies are in compliance with applicable or relevant and appropriate state
environmental laws and regulations. The uTJDElf concurs with the selected remedy for the
Area A Landfill. A copy of the declaration of concurrence is attached as Appendix D.
36
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APPENDIX A
RESPONSIVENESS SUMMARY
-------
APPENDIX A
RESPONSIVENESS SUMMARY
Overview
At the time of the public comment period, the United States Navy had selected a preferred
alternative to address source control of landfill wastes at the Area A Landfill. This preferred
alternative was selected in coordination with the United States Environmental Protection (EPA)
and Connecticut Department of Environmental Protection (CTDEP). Other members of the
Restoration Advisory (RAB) for this project were also involved hi discussions and planning of
the selected alternative. Technical details of the alternative have been discussed and no
fundamental objectives to its selection have been raised.
f
The sections below describe the background of community involvement with the project and the
Navy's responses to comments received during the public comment period.
Background of Community involvement
Throughout the history of the contamination investigations and remedial alternative development
activities at' Naval Submarine Base - New London (NSB-NLON), the community has been
actively involved. Community members and other interested parties have been kept abreast of
site activities through informational meetings, published "fact sheets and information updates,"
press releases, public meetings, and Technical Review Committee (TRC) and RAB meetings.
The TRC was established in 1988 and was later (late 1994) reorganized and renamed the RAB.
The RAB (formerly TRC) has been an important vehicle for community participation in the
NSB-NLON Installation Restoration Program (IRP). The RAB consists of representatives of the
Navy, EPA, CTDEP, planners and officials of neighboring towns, Navy and EPA contractors,
and local residents with scientific knowledge of or interest in the sites. The RAB meets
regularly to review technical aspects of the NSB-NLON IRP and provides a mechanism for
community input to the program.
To ensure that the community is well informed about NSB-NLON IRP activities, the Navy has
provided and will continue to provide the public with the following sources or vehicles of
information.
Public Information Repositories. The Public Libraries in Groton, Ledyard, and the
Naval Submarine Base are the designated information repositories for the Subase IRP.
Key Contact Persons. The Navy has designated a Public Affairs Officer ("PAO") as
an information contact for the Subase. Representatives from the Navy, EPA, and the
A-l
-------
Connecticut Department of Environmental Protection attend all public meetings and hearings.
Addresses and phone numbers of key contact persons are included in all information materials
distributed to the public, including any fact sheets or press releases.
Mailing List. To ensure that information materials reach the individuals who are
interested in or affected by the IRP activities at the Subase, the Navy maintains and will
regularly update a mailing list of interested persons. Anyone interested in being placed on the
list can do so by contacting the Subase Public Affairs Officer.
Regular Contact With Local Officials. The Navy has managed and will continue to
arrange regular meetings to discuss the status of the IRP with the RAB, which includes
representatives from neighboring towns. The Navy contacts other town officials on an as-needed
basis.
Press Releases and Public Notices. The Navy has issued and will continue to issue
press releases to local media sources to announce public meetings and comment periods, the
availability of the IRP reports and plans, and to provide general information updates when and
as the Public Affairs Officer sees fit.
Public Meetings. The Navy has held and will continue to hold informal public meetings
as needed to keep residents and town officials informed about IRP activities at the Subase, and
of significant milestones in the IRP. The meetings include presentations by Navy technical staff,
EPA personnel, and/or support contractors for both agencies. The meetings also include a
question-and-answer period. Minutes of meetings during public comment periods are included
in the Administrative Record for public reference.
Fact Sheets and Information Updates. The Navy has been developing a series of
fact sheets which are mailed to public officials and other interested individuals and/or used as
handouts at the public meetings. Each fact sheet includes a schedule of upcoming meetings and
other site activities. The fact sheets may explain why the Navy is conducting certain activities
or studies, update readers on potential health risks, or provide general information on the IRP
process.
A detailed formal NSB-NLON Community Relations Plan was published in February of 1994.
The plan identifies issues of community interest and concern regarding the NSB-NLON. The
plan also describes a program of community relations activities that the Navy will conduct during
the IRP.
The activities of the community relations program outlined in this plan have the following
specific objectives: (1) to keep local officials, citizens, military personnel, and the media
informed of site activities; (2) to increase community awareness of the goals and procedures of
the IRP; and (3) to provide opportunities for public involvement in the cleanup process.
A-2
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The information in the Community Relations Plan is based upon:
interviews with area residents and local officials conducted in Groton and Ledyard
on October 2-3, 1991;
interviews with area residents and local officials conducted by phone in
September and October of 1991;
input of the TRC or RAB which had regularly met to discuss progress at the
Subase;
public comments and questions at public information meetings held in 1990 and
1991;
review of Navy site files; and
discussions held with Navy, EPA, contractors, and technical and public affairs
staff.
EPA published a notice and brief analysis of the Proposed Plan in the New London Day on
June 1, 1995 and made the plan and the administrative record available to the public at the
Groton Public Library, the Bill Library and the Naval Submarine Base Library. A fact sheet
regarding the Proposed Plan was also prepared and distributed to all persons on the Navy's
public mailing list.
On June 1, 1995, the Navy held an informational meeting to discuss the cleanup alternatives
presented in the Focused Feasibility Study and to present the Proposed Plan. Also during this
meeting, the Navy answered questions from the public. From June 1, 1995 to June 30, 1995
the Navy held a .30-day public comment period to accept public comment on the alternatives
presented in the Feasibility Study and the Proposed Plan, and on any other documents previously
released to the public. On June 28, 1995, the Navy held a public hearing to discuss the
Proposed Plan and to accept any oral comments. A transcript of this meeting is included in this
responsiveness summary.
Summary of Comments Received During the Public Comment Period
During the public comment period one set of comments, dated June 30, 1995, was received.
At the public hearing held on June 28, 1995 no comments were received.
1. Comment: The commentor had several detailed technical comments regarding the
design of the cap, groundwater interception system and post-closure
groundwater monitoring system.
Response: These components of the final remedy are presently being designed. The
A-3
-------
comments bring up several important points which the Navy will carefully
address during the design phase of this project. The commentor will be
given the opportunity to review preliminary designs and design analyses
and provide further comments at that time.
2. Comment: There is an apparent conflict between the Proposed Plan and the
accompanying Fact Sheet regarding whether the leachate collection system
will be installed. The Proposed Plan states on pages 10 and 11 that a
leachate collection system will be installed. However, the Fact Sheet
states on page 3 that the design will include a leachate collection system
"if necessary". It is the State's understanding that the Navy intends to
decide, based on predesign studies, whether it will be necessary to install
a leachate collection system. The State supports this approach. Any
decision regarding the necessity of leachate collection must be by mutual
agreement between the Navy, EPA, and the State, and must be based on
data from a adequate groundwater monitoring program. If a leachatcr
collection system is installed at the Area A Landfill, the Navy will still be
required to evaluaie whether additional steps are needed to address
contaminated groundwater originating from the landfill.
Response: The Navy intends to perform a predesign study to determine the type of
leachate collection system that may be installed as well as the need for
such a system. The leachate collection system will only be installed if the
EPA, CT DEP, and the Navy agree that it is necessary.
A-4
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APPENDIX B
COMPARATIVE ANALYSIS OF ALTERNATIVES
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TAULK 5-1
COMPARATIVE ANALYSIS SUMMARY
AKKA A LANDFILL
Assessment Factors
Alternative 2I.-I
No Action
Alternative 21s
Cap
Alternative 21. -I
Off-Silt Incineration
Allcrnallve 2I.-5
Off-Slle KCUA Landfill
Overall Protection of
Human lletlth and the
Environment
No significant reduction In risk.
Eliminates risk due to direct contact
and Ingesilon/inhalatlon. Prevents
erosion and Infiltration.
Eliminates risk due to direct contact
and ingestion/inliaialion and, by
removing hot spots, protects future
utility construction workers. Prevents
erosion and Infiltration. Eliminates
some contaminated material.
Eliminates risk due to direct contact
and ingesiion/inlulaiion and, by
removing hot spots, protects future
utility construction workers. Prevents
erosion and Infiltration. Eliminates
some contaminated material.
2. Compliance wiih ARARs
Hie following ARARs arc not met:
Pederal and stale KCKA hazardous
waste disposal area closure
standards
ARARs for ground and surface waicr
quality are not wltliln Hie scope of Oils
Interim remedial action. Tills
alternative does not Improve water
quality.
This alternative meets all ARARs.
AKAKs for ground anil suifacc water
quality are not within the scope of iliis
interim remedial action. .This
alternative would improve water quality
to the extent that Infiltration Is
prevented.
This alternative meets all ARARs.
ARARt for ground awl surface water
quality ate not within the scope of this
Interim remedial action. This
alternative would improve groundwaler
quality to the extent that some
contaminated tolls are removed ami
inliliMiion Is prevented.
This alternative meets all ARARs.
ARAIls for ground and surface water
quality aie nut williin the stupe ul this
interim remedial action. This
alternative would improve groundwaler
quality to die extent Uiat some
contaminated soils are removed and
infiltration is pievcrilcd.
3. Long-Term Effectiveness
and Permanence
Magnitude of Residual
Risk
No reduction In constituent
concentrations In any media.
Dy preventing direct contact, risks to
human health are prevented except for
risks to potential future conjunction
workers which are low.
Dy preventing direct contact, human
health risks due to direct contact arc
eliminated and risks to future
utility/construction workers are reduced
lo very low levels by removal of
contaminated pen hot spots.
Dy preventing direct contact, human
health risks due to direct contact ate
eliminated and risks to future
utility/construction workers are
reduced to very low levels by removal
of contaminated I'CD hot spots.
Adequacy and Reliability
of Controls
No controls over remaining
contamination.
Controls are considered reliable and
adequate: however. If utility/
construction activities lake place
without adequate protection there would
be potential health risks.
Controls are considered reliable and
adequate. Contaminated soil hot spots
aie removed, thus long Icim protection
will be provided in these areas.
Controls are considered reliable and
adequate. Contaminated soil hot spots
are removed thus long-term protection
will be provided in these areas.
4. Reduction of Toxiclly
Mobility, or Volume
No reduction of loxlcity, mobility or
volume.
No reduction in loxicily or volume.
Contaminants in unsaluraled zone will
be less mobile due to the reduced
infiltration.
No reduction In loxicily or volume for
the majority of landfill soils.
Contaminants In the unsaluraled zone
will be less mobile due lo the reduced
Infiltration. Soil hot spots will be
eliminated, thereby reducing me total
volume of contaminated materials on
site. Ultimately, these soil hoi spots
will be incinerated, thereby destroying
the PCDs which will result in a net
reduction in loxicily.
No reduction In toxicily or volume for
the majority of landfill soils.
Contaminants In the unsaiunted zone
will be less mobile due to the reduced
infiltration. Soil hot spots will be
eliminated, thereby reducing me total
volume of contaminated materials on
site. Ultimately, these soil hot spots
will be landfilled. therefore there is no
net reduction in loxicily. However,
mobility will be reduced at the off site
RCRA landfill.
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TABLE 5-1 (continued)
COMPARATIVE ANALYSIS SUMMARY
AREA A LANDFILL
Assessment Factors
5. Short-Tenn Effectiveness
Time until protection is
achieved
Protection of community
during remedial action
Protection of workers
during remedial action
6. Implememabilily
Technical feasibility
Administrative feasibility
Availability of services
and materials
1. Cost
Capital cost
O&M (Present Worth)
Costs
Total Cost
8. Stale Acceptance
9. Community Acceptance
Alternative 2U-1
No Action
Not applicable.
Risks to community not increased;
however, contaminants still have the
potential to migrate off site.
Not applicable.
No activities to Implement.
No approval necessary.
No services or material required.
$0
$0
$0
No comments received from the State
regarding llils alternative.
No comments received from the public
regarding tills alternative.
Alternative 2IX»
Cn|>
Cap placed within 12 months.
Potential for windblown dust during
grading activities. 1'rolecliim provided
by use of dust suppressants.-
Protection from Ingeslion, direct
contact, and Inhalation of soil provided
by proper health and safely procedures.
Cover installation easy to implement.
Some coordination required with
hazardous waste agencies to ensure that
cap and closure meet relevant and
appropriate requirements, and with
water discharge agencies to ensure that
the groundwater discharge (o the
wetlands meets substantive
requirements.
Contractors ami materials are locally
available.
$3,910.869
$1,823.818
.$5,73-1,687
The Stale concurs (in a teller dated
August 7, I99S) Ilial this is the
preferred alternative.
No comments received from (he public
regarding (his alternative.
Alternative 2L-4
Off .Site liiclnci iitlnn
Soils excavated and removed within 14
months.
Potential for windblown dust during
grading and excavation activities.
Protection provided by use of dust
suppressants. Small potential for spills
during transport.
Protection from Ingeslion, direct
contact, and Inhalations of soil provided
by proper health and safely procedures.
Cover installation and removal activities
easy to Implement.
Some coordination required with
hazardous waste agencies to ensure dial
cap and closure meet relevant and
appropriate requirements, and with
water discharge agencies lo ensure (hat
the groundwaler discharge to the
wetlands meets substantive
requirements. Approvals required for
disposition of I'CIl hot spots in the off-
site Incineration. No difficulties nre
anticipated.
Contractors and materials are locally
available. Off-site incineration capacity
Is available. Temporary capacity
shortfalls are possible.
$4.409,300
$1,823.818
$6.233,118
No comments received frum the Slate
regnrding this alternative.
No comments received from (he public
regarding Urn alternative.
Alternnllve 21^5
Off-Site ItCKA l.nmlflll
Soils excavated and removed within 13
months.
Potential for windblown dust during
grading and excavation activities.
Protection provided by use of dust
suppressants. Small potential for spills
during transport.
Protection from ingestlon. direct
contact, and Inhalations of soil
provided by proper health and safely
procedures.
Cover Installation and removal
activities easy lo implement.
Some coordination required with
hazardous waste agencies lo ensure
lhal cap and closure meet relevant and
appropriate requirements, and with
water discharge agencies lo ensure lhal
die groundwaler discharge lo the
wetlands meets substantive
requirements. Approvals required for
disposition of PCII hot spots in the off-
site landfill. No difficulties rue
anticipated.
Contractors and materials are locally
available. Adequate off-site landfill
capacity Is available.
$4.127,300
$1,823,818
$5.951,118
No comments received from the Slate
regarding this alternative.
No comments received from the public
regarding this alternative.
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APPENDIX C
ARAR SUMMARY TABLES
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NAVAL SUBMARINE BASE - NEW LONDON SUPERFUND SITE
AREA A LANDFILL
ALTERNATIVE 2L-3
RCRA SUBTITLE C CAP
CHEMICAL-SPECIFIC ARARs AND TIlCs
Medium
Requirements
Status
Synopsis of Requirement
Action to be taken to Attain AKAK
STATE
Soil
State Proposed
Connecticut Cleanup
Standard Regulations
(COS § 22a-133k)
TBC
These regulations are being adopted
under the statutory authority provided
by COS § 22a-l33k. They will
provide specific numeric cleanup
criteria for a wide variety of
contaminants in soil. Separate criteria
will be established Tor threats to human
health and environmental receptors
posed hy direct contact with
contaminants.
The Soil Cleanup Standards will be
considered in the design of the proposed
remedy.
Water
Stiitc Water Quality
Standards (COS § 22a-
426)
Applicable
Connecticut's Water Quality Standards
were adopted under this statute. They
establish specific numeric criteria, and
anti-degradation policies for
groundwater and surface water.
Remedial activities will be undertaken in a
manner that is consistent with the
antidegradation policy in the Water Quality
Standards. If any remedial activities occur
that are regulated under these provisions, the
use of engineering controls and best
management practices may be required to
prevent or minimize adverse impacts to (lie
waters of (he State.
Water
State Water Pollution
Control (RCSA §§ 22a-
430-1 to 8)
Applicable
These rules establish criteria for water
and stormwater discharge to surface
water, groundwater and POTWs.
The proposed alternative includes collection
and discharge of upgradient surface and
groundwaler. Any discharges will meet the
substantive requirements of these regulations,
including treatment if necessary.
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NAVAL SUBMARINE BASE-NEW LONDON SUPERFUND SITE
AREA A LANDFILL
ALTERNATIVE 2L-3
RCRA SUBTITLE C CAP
ACTION-SPECIFIC ARARs AND TBCs
Medium Requirements
Status
Synopsis of Requirement
Action to be taken to Attain ARAR
FEDERAL
Wasie
Waste
Federal RCRA - General
requirements (40 CFR
Part 264 Subpart A)
Federal RCRA -
Preparedness and
Prevention (40 CFR Part
264 Subpart C)
Relevant and
Appropriate
Relevant and
Appropriate
Establishes general requirements for
owners and operators of hazardous
waste treatment, storage, and disposal
facilities.
Establishes requirements for
minimizing the possibility of fire,
explosion, or release of hazardous
material.
The cap and associated systems will be
designed to meet these requirements.
The cap and associated systems will be
designed to meet these requirements.
Waste
Federal RCRA -
Contingency Plan and
Emergency Procedures
(40 CFR Part 264 Subpart
D).
Relevant and
Appropriate
Establishes contingency plan
requirements in the event of fire,
explosion, or release from a facility.
The remedy will meet lite substantive
requirements specified in these regulations
through the preparation and implementation of
appropriate plans and procedures.
Waste
Federal RCRA - Releases
from Solid Waste
Management Units (40
CFR Part 264 Subpart F
Relevant and
Appropriate
Regulates releases from Solid Waste
Management Units ("SWMUs").
The remedy will meet the substantive
requirements specified in these regulations.
Waste
Federal RCRA - Closure
and Post-Closure
Requirements (40 CFR
Part 264 Subpart G).
Relevant and
Appropriate
Details general requirements for
closure and post-closure of hazardous
waste facilities.
The cap and associated systems will be
designed to meet these requirements.
-------
Wasle Federal USEPA
Technical Guidance -
Final Covers on
Hazardous Waste
Landfills and Surface
Impoundments, EPA/530-
SW-89-047.
TBC
Presents Icchnicnl specifications for the
design of multi-layer covers at landfills
where hazardous wastes were disposed.
The cap and associated systems will be
designed to meet these design specifications.
Waste Federal PCD regulation
under TSCA (40 Part
CFR 761)
Applicable
These standards govern the storage of
PCI) items.
The management of PCI) items during
implementation of the remedy will be
conducted in accordance with these standards.
STATE
Waste State Hazardous Waste
Management: Generator
& Handler
Requirements - General
Standards, Listing, &
Identification (RCSA §§
22a-449(c)100-101)
Applicable
These sections establish standards for
listing and Identification of hazardous
waste. The standards of 40 CFR Parts
260 to 261 arc incorporated by
reference.
Hazardous waste determinations will be
performed and the wastes will be managed in
accordance with requirements of these
regulations, if necessary.
Wasle State Hazardous Waste
Management: Generator
Standards (RCSA §§ 22a-
449(c)l02)
Applicable
This section establishes standards for
various classes of generators. The
standards of 40 CFR Part 262 arc
incorporated by reference. Storage
requirements given at 40 CFU § 265.15
are also included. These provisions arc
applicable if hazardous waste is
generated on the site as part of the
remedy.
Any hazardous waste generated through
excavation or other activities will be m;inagcd
in accordance with the substantive
requirements of these regulations.
Waste State Hazardous Waste
Management: TSDF
Standards (RCSA § 22a-
449(c)l04)
Relevant and
Appropriate
This section establishes standards for
closure, post-closure, and groundwater
monitoring. The standards of 40 CFR
Part 264 are incorporated by reference.
Underground injection of hazardous
wastes, and placement of free liquids in
landfills arc prohibited.
The proposed cap design will comply with the
closure and post-closure requirements of this
regulation. The proposed remedial action
includes groundwater monitoring.
-------
Waste
State Hazardous Waste
Management: TSDF
Standards (RCSA § 22ii-
449(c)l04)
Relevant and
Appropriate
This section establishes standards for
closure, post-closure, and groundwater
monitoring. The standards of 40 CPU
Part 264 arc incorporated by reference.
Underground injection of ha/.ardous
wastes, and placement of free liquids in
landfills arc prohibited.
The proposed cap design will comply with the
closure and post-closure requirements of this
regulation. The proposed remedial action
includes groundwater monitoring.
Waste
Stntc Hazardous Waste
Management: Interim
Status Facilities and
Groundwater Monitoring
Requirements, Closure
and Post-Closure
Requirements (RCSA §
22a-449(c)105)
Relevant and
Appropriate
This section establishes standards for
closure, post-closure, and groundwater
monitoring. The standards of 40 CFR
Part 265 are incorporated by reference.
The Commissioner may require
groundwnlcr monitoring based on site
specific considerations.
The proposed cap design will comply with the
closure and post-closure requirements of this
regulation. The proposed remedial action
includes groundwater monitoring.
Waste
State Solid Waste
Management (RCSA §§
22a-209-l to 15)
Applicable
Establishes standards for closure of
solid waste disposal areas.
These portions of the regulations that are
more stringent than Federal RCRA Subtitle D
regulations will be met.
Waste
State Safe Storage of Oil
and Chemical Liquids
(RCSA §§ 29-337-1 to 3)
Applicable
These rules govern (he storage of
hazardous materials, including
flammable liquids and other chemicals.
Storage of oil and other waste materials will
be conducted in accordance with the
requirements of these regulations.
FEDERAL
Air
Federal Clean Air Act -
National Emission
Standards for Hazardous
Air Pollutants
("NESHAPs"), 40 CFR
Part 61.
Relevant and
Appropriate
Establishes emission levels for eight
listed hazardous air pollutants emitted
Jrom particular types of facilities.
The gas collection and treatment system will
be designed to attain the NESHAP numerical
standards for potential landfill gases,
including benzene and vinyl chloride.
-------
Air Federal Clean Air Act -
Non-methane organic
compounds ("NMOCs")
(Proposed rule - 56 PR
24468, to be codified at
40 CFR Part 60 Subpart
WWW).
TBC
Regulations would require NMOC-
spcciflc gas collection and control
systems, monitoring, nnd gas
generation estimates. The proposed
rule would also establish a performance
standard Tor NMOCs emissions from
municipal solid waste landfills.
The proposed regulations will be considered
in the design of the land HI) gas collection and
treatment system.
STATE
Air
State Air Pollution
Control - Control of
Organic Compound
Rmissions (RCSA § 22a-
174^20)
Applicable
Subsection (0 sets standards for
emission of organic compounds.
Incineration of organohalocarbons is
prohibited under subsection (f)(<))(A).
The landfill gas collection and treatment
system will be designed to comply with the
substantive requirements of this regulation.
Air
State Air Pollution
Control - Control of
Odors (RCSA § 22a-174-
23)
Applicable
This section prohibits emission of any
substance that constitutes a nuisance
because of objectionable odor. Severn)
compounds arc deemed to constitute a
nuisance if they exceed specific
concentrations.
Site remediation activities will be planned to
control the release of objectionable odors
from the site so that the activities comply
with the substantive requirements of this
regulation.
Air
State Air Pollution
Control - Control of
Hazardous Air Pollutants
(RCSA § 22a-174-29)
Applicable
This section establishes testing
requirements and allowable stack
concentrations for many specific
substances.
Direct discharges to the air from the landfill
gas collection and treatment system will be
designed to meet the substantive requirements
of these regulations so that the numeric
criteria are not exceeded.
Air State Air Pollution
Control - Control of
Paniculate Emissions
(RCSA § 22a-l74-18)
Applicable
This subsection sets specific standards
for participate emissions. Specific
standards that may apply particularly to
the landfill include Fugitive Dust (I8I>),
and Incineration (I8c). Cias flares arc
regulated as incinerators.
Any activities involving excavation, landfill
cap construction, or landfill gas flaring will
be designed to meet with the substantive
requirements of these regulations so that the
numeric criteria are not exceeded.
-------
Water Slate Water Pollution
Control (COS § 22a-430)
Applicable
This section prohibits discharge to the
waters of the Slate without meeting the
substantive requirements or (he Slide's
Water Quality Standards. This section
establishes requirements for many
categories of discharges, including
stormwatcr.
The proposed remedy may create slormwaler
runoff that may require treatment under CGS
§ 22a-'l30b. Any discharges, including
slormwater, will meet the substantive
requirements of (his section, including
treatment if necessary.
Water State Connecticut Water
Diversion Policy Act
(CGS §§ 22a-365 to 378)
Applicable
These rules regulate many diversions of
the waters of (he State. Several broad
categories are exempt, including any
diversion of less than 50,000 gallons
per day and any discharge permiltcd
under CGS § 22a-<130. Under Section
22a-373, the Commissioner may
impose limitations and conditions
including monitoring, schedule of
diversion, etc. Under CGS § 22a-378,
the Commissioner may temporarily
suspend such requirements if a water
supply emergency has been declared.
Any non-exempt diversion will be carried out
in accordance with (he substantive
requirements of (hese statutes. The Navy will
coordinate with the Connecticut Department
of Environmental Prelection lo idcnlify any
such requirements and ensure (hat they arc
met.
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NAVAL SUBMARINE BASE-NEW LONDON SUPERKUND SITE
AREA A LANDFILL
ALTERNATIVE 2L-3
RCRA SUBTITLE C CAP
LOCATION-SPECIFIC ARARs AND TIlCs
Medium
Requirements
FEDERAL
Wetlands
Wetlands
Federal .Executive Order
on Protection of Wetlands
(E.O. 1 1990, 40 CFR
Part 6, App. A).
Federal Clean Water Act
§ 404 - Dredge and Pill
Activities (40 CFR Part
230; 33 CFR Parts 320-
328).
STATE
Surface
Water and
Wetlands
State - Inland Wetlands
and Watercourses
Regulations (RCSA §§
22a-39-l through 15).
Status
Applicable
Applicable
Synopsis of Requirement
Action to be taken to Attnin ARAK
Requires federal agencies lo avoid
impacts associated with the destruction
or loss of wcllands, minimize potential
harm, preserve and enhance wetlands,
and avoid support of new construction
in wetlands if a practicable alternative
exists.
Requires that for dredging or filling of
wetlands: no practicable nllci natives
exist; the activity will not cause a
violation of slate water quality
standards or significant degradation of
the water; and adverse effects will be
minimized.
The landfill cap will be designed to minimi/c
impacts to the adjacent wetlands. To the
extent necessary, wetlands restoration and/or
replication will be undertaken.
The landfill cap will be designed lo meet
these standards mid minimize impacts lo the
adjacent wetlands. To the extent necessary,
wetlands restoration and/or replication will be
undertaken.
Applicable
Regulates any operation within or use
of a wetland or watercourse involving
removal or deposition of material, or
any obstruction, construction, alteration
or pollution of such wetland or
watercourse.
The landfill cap and the dredging of waste
materials will be designed to minimize
impacts to the Area A Wetland. To (he
extent necessary, wetlands restoration and/or
replication will be undertaken.
-------
Surface
Water and
Wetlands
Slate - Inland Wetlands
and Watercourses Act -
General Requirements
(COS § 22a-45a)
TBC
This section governs minor activities
including installation of water quality
monitoring equipment such as staff
gauges, water recording and water
quality testing devices, and survey
activities, including excavation of test
pits and core sampling. The
Commissioner may require
implementation of bust management
practices. The Department is currently
drafting these requirements, and
expects to issue them before the final
remedy is selected for this site.
Once regulations are adopted, any wel.ls, test
borings, soil sampling, or other similar
activities will be conducted in accordance
with the substantive requirements of these
regulations, if any.
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APPENDIX D
DECLARATION OF CONCURRENCE
-------
STATE OF CONNECTICUT
DEPARTMENT OF ENVIRONMENTAL PROTECTION
79 ELM STREET HARTFORD, CONNECTICUT 06106
. - .. . PHONE: (203) 424-3001
idney J. HolbrooK
Commissioner August 7, 1995
Ms. Linda M. Murphy, Director
United States Environmental Protection Agency
Waste Management Division
JFK Federal Building, HAA-CAN2
Boston, MA 02203-2211
Captain Leo Dominique, Commanding Officer
Naval Submarine Base New London
Box 00
Groton, CT 06349
Re: State Concurrence with Capping of Area A Landfill
Naval Submarine Base New London
Dear Captain Dominique and Ms. Murphy:
The Connecticut Department of Environmental Protection (CTDEP) concurs with the remedial
action for source control selected by the US Navy and The US Environmental Protection Agency
for the first Operable Unit of the Area A Landfill at the Naval Submarine Base New London hi
Groton, Connecticut. The source control remedial action is described in detail in the proposed plan
dated May 1995, and in the Record of Decision dated September 1995.
Concurrence with EPA's selected remedy for source control at the Area A Landfill shall in no way
affect the Commissioner's authority to institute any proceeding to prevent or abate violations of law,
prevent or abate pollution, recover costs and natural resources damages, and to impose penalties for
violations of law, including but not limited to violations of any permit issued by the Commissioner.
Sincerely,
Sidney J. Holbrook
Commissioner
SJH:MRL
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