United States
Environmental Protection
Agency
Off ice of
Emergency and
Remedial Response
EPA/ROD/R01 -92/071
May 1992
PB93-963704
x°/EPA Superfund
Record of Decision:
Otis Air National Guard/Camp
-------
NOTICE
The appendices listed In the index that are not found In this doCument have been removed at the reque~u of
the issUing agency. Th8V contain material which supptement, but adds no further applicable information to
the content of the document. All supplemental material is, however. contained In the administrative record
for this site. .
. ,\ J'
'U.:.: '
. .
. v. .
-------
REPORT DOCUMENTATION \1. REPORT NO. T~ I. A8c1pi8nt'. ACC888Ion No.
PAGE EPA/ROD/R01-92/071
4. 1118 8l1li 8ubIII8 5. A8part Dat
SUPERFUND RECORD OF DECISION OS/20/92
Otis Air National Guard/Camp Edwards, MA ..
First Remedial Action - Interim
7. AuIhor(.) L Pi8rfonninCI Orpnlalion A8pL No.
8. P8rfonnkII Org8InIIatIon .... 8l1li Add- 10. PI'ojKtIT88klWorII UnIt No.
11. C:-d(C) or Gr8nt(G) No.
(C)
(0)
1~ 8poMorIng 0rg8NDII0n ..... 8l1li AddrM8 11. Type af Report . P8IIocI Cowred
U.S. Environmental Protection Agency 800/000
401 M Street, S.W.
washington, D.C. 20460 14.
15. ~No-
PB93-963704
15. Abd8c:t (LInt: 20D wonIa)
The 22,000-acre Otis National Guard/Camp Edwards site is a former military vehicle
maintenance facility on Cape Cod, Massachusetts, within the Massachusetts Military
Reservation (MMR). The Area of Contamination Chemical Spill Area Number 4 (AOC CS-4)
plume extends 11,000 feet and is located 1.1 miles from the southern boundary of MMR.
Land use surrounding MMR is predominantly residential and light industrial. Ground
water beneath Cape Cod has been classified as a Class I, Sole Source Aquifer under the
Safe Drinking Water Act. From 1940 to 1984, the site was used by the Federal
Government for various purposes. From 1940 to 1946, the U.S. Army operated the site
for maintenance of military vehicles, and from 1955 to 1973, the USAF operated the
vehicle area. Wastes and equipment handled at AOC CS-4 included oils, solvents,
antifreeze, battery electrolytes, paint, and waste fuels. Additionally, the northern
portion of AOC CS-4 was used as a storage yard for wastes generated by shops and
laboratories operating at MMR. Liquid wastes were stored in containers or underground
storage tanks (USTs) in an unbermed area or deposited in USTs designated for motor
gasoline. The UST waste storage contents were removed in 1984, and the AOC CS-4 site
has been inactive since 1986. Since 1986, the DOD's Installation Restoration Program
(See Attached Page)
17. Doc:um8nt Anelyel. L D88cr1ptolS
Record of Decision - Otis Air National Guard/Camp Edwards, MA
First Remedial Action - Interim
Contaminated Medium: gw
Key Contaminants: VOCs (PCE, TCE)
b. 1den1i1illr8l000n-EncIed T8f1118
Co COSA T1 FI8IdIGraup
18. Avllil.blMty Stetement 18. Security CI... (Thi. Report) 21. No. 01 Peen
None 82
20. SecurIty Cle.. (Thi. Peee) 22. Price
N()np
272 4-77
50272.101
(See ANSl-Z39.18)
See In.lrUCllon. on Rewf8e
(Formerty NTlS-35)
-------
EPA/ROD/R01-92/071
Otis Air National Guard/Camp Edwards, MA
First Remedial Action - Interim
Abstract (Continued)
staff has conducted several investigations at MMR, which revealed that ground water was
contaminated with VOCs and may migrate off of the MMR to the south. This ROD addresses
OU2, the interim action for MMR AOC CS-4 ground water to prevent further d~wn gradient
migration of the contaminants. Future RODs will address a final remedy for the AOC CS-4
plume upon completion of the AOC CS-10 ground water plume study, while contaminated soil
will be addressed as part of a removal action. The primary contaminants of concern
affecting the ground water are VOCs, including PCE and TCE.
The selected remedial action for this site includes onsite pumping and treatment of 790
million gallons of contaminated ground water using carbon adsorption to remove VOCs;
monitoring the influent and effluent of the carbon absorption treatment, and discharging
the treated water to an onsite infiltration trench; and monitoring ground water. The
estimated present worth cost for this remedial action ranges from $2,113,000 to
$4,528,000, which includes a present worth O&M cost ranging from $472,000 to $1,012, 000
for 5 years. .
PERFORMANCE STANDARDS OR GOALS: Chemical-specific clean-up goals for ground water are
based on SDWA MCLs and state standards and include PCE 5 ug/l, and TCE 5 ug/l, (1~6
-------
INSTALLATION RESTORATION PROGRAM
RECORD OF DECISION
INTERIM REMEDIAL ACTION
WEST TRUCK ROAD MOTOR POOL (AQC CS-4)
GROUNDWATER OPERABLE UNIT.
MASSACHUSETTS MILITARY RESERVATION
CAPE COD, MASSACHUSETTS
FINAL
MAY 1992
HAZWRAP SUPPORT CONTRACTOR OFFICE
Oak RIdge. Tennessee 37831
Managed by MARnN MARIE'ITA ENERGY SYSTI:M5. INC.
-------
INSTALLATION RESTORATION PROGRAM
RECORD OF DECISION
INTERIM REMEDIAL ACTION
WEST TRUCK ROAD MOTOR POOL (AOC CS-4)
GROUNDWATER OPERABLE UNIT
MASSACHUSE'ITS MILITARY RESERVATION
CAPE COD, MASSACHUSE'ITS
FINAL
Prepared for:
HAZWRAP Suppon Contractor Office
Oak Ridge, Tennessee
Managed by:
Manin Marietta Energy Systems, Inc.
for the
U.S. Department of Energy
Under Contract No. DE-AC05-840R21400
Prepared by:
ABB Environmental Services, Inc.
Portland, Maine
Project No. 7030-04
MAY 1992
3929
-------
Section
2.0
3.0
. 4.0
5.0
6.0
7.0
8.0
9.0
3929
1.0
AQC CS-4 RECORD OF DECISION
MASSACHUSETIS MILITARY RESERVATION
TABLE OF CONTENTS
Title
Page No.
DECLARATION FOR THE RECORD OF DECISION.......... 1-1
SITE NAME, LOCATION, AND DESCRIPTION............. .. 2-1 "
SITE HISTORY AND ENFORCEMENT ACTIVITIES.......... '3-1
3.1
3.2
LAND USE AND REsPONSE HISTORY. . . . . . . . ; . . . . . . . . . .. 3-1
ENFORCEMENT HISTORY. . . . . . . . . . . . . . . . . . . . . . . . . . .. 3-3
COMMUNITY PARTICIPATION. . . . . . . . .. . . . . . . . . . . . . . . . ".. 4-1
SCOPE AND ROLE OF RESPONSE ACTION. . . . . . . . . . . . . . .. 5-1
SUMMARY OF SITE CHARAcrERISTICS .................: 6-1
6.1
6.2
SOIL CONTAMINATION AsSESSMENT. . . . . . . . . . . . . . . . . . .. 6-1
GROUNDWATER CONTAMINATION AsSESSMENT. . . . . . . . . .. 6-4
SUMMARY OF SITE RISKS.. ..,......... . ...... ... ... ... 7-1
DEVELOPMENT AND SCREENING OF ALTERNATIVES. . . . .. 8-1
8.1
8.2
STATUTORY REQUIREMENTS/RESPONSE OBJECTIVES. . . . .. 8-1
ALTERNATIVES DEVELOPMENT AND SCREENING. . . . . . . . .. 8-2
DESCRIPTION OF ALTERNATIVES. . . . . . . . . . . . . . . . . . . . . .. 9-1
9.1 CONTAINMENT ALTERNATIVES ANALYZED. . . . . . . . . . . . . .. 9-1
9.1.1 Alternative GW-l: Minimal No Action. . . . . . . . . . .. 9-1
9.1.2 Alternative GW-2: Extraction, Carbon Adsorption
" Treatment, and Discharge. . . . . . . . . . . . . . . . . . . . .. 9-2
9.1.3 Alternative GW-3: Extraction, Air-stripping
Treatment, and Discharge. . . . . . . . ; . . . . . . . . . . . .. 9-4
9.1.4 Alternative GW-4: Extraction, Ultraviolet/Oxidation
Treatment, and Discharge. . . . . . . . . . . . . . . . . . . . .. 9-5
-------
AOC CS-4 RECORD OF DECISION
MASSACHUSEITS MlUTARY RESERVATION
TABLE OF CONTENTS
( continued)
Section
Title
Pa~e No.
9.2
SOURCE CONTROL ALTERNATIVES ANALYZED... ... .. . ... 9-6
10.0 SUMMARY OF THE COMPARATIVE ANALYSIS OF
. ALTERNATIVES. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .. 10-1
10.1 THREsHOLD CRITERIA. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10-1
10.2 PRIMARY BALANCING cRrrERIA . . . . " . . . . . . .. . . . . . . . .. 10-1
10.3 MODIFYING CRITERIA. . . . . . . . . . . . . . . ... . . . . . . . . . . . .. 10-2
. 10.4 OVERALL PROTECTION OF HUMAN HEALTH AND THE
ENVIRONMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. -10-3
10.5 COMPLIANCE WITH ARARS ......................... 10-3
10.6 LoNG-TERM EFFECTIVENESS AND PERMANENCE. . . . . . . . .. 10-3
10.7 REDUCTION OF MOBILITY, TOXICITY, OR VOLUME. . . . . .. 10-4
10.8 SHORT,-TERM EFFECTIVENESS. . . . . . . . . . . . . . . . . . . . . . .. 10-4
10.9 IMPLEMENT ABILITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10-5
10.10 COST........................................... 10-5
10.11 STATE ACCEPTANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10-5
10.12 COMMUNITY ACCEPTANCE. . . . . . . . . . . . . . . . . . . . . . . . .. 10-6
11.0 THE SELECTED INTERIM REMEDY. . . . .. . . . . . . . .. . . . . .. 11-1
11.1 CLEAN-UP LEVELS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11-1
11.2 DESCRIPTION OF REMEDIAL COMPONENTS. . . . . . . . . . . . .. 11-3
12.0 STATUTORY DETERMINATIONS..... .................... 12-1
12.1 THE SELECTED INTERIM REMEDY IS PROTECI1VE OF HUMAN
. HEALTH AND THE ENVIRONMENT. . . . . . . . . . . . . . . . . . .. 12-1
12.2. THE SELECTED INTERIM REMEDY ATTAINS ARARs ...... 12-2
12.2.1. Location-specific ARARs ..................... 12-2
12.2.2 Chemical-specific ARARs . . . . . .. . . . . . . . . . . . . .. 12-2
12.2.3 Action-specific ARARs . . . . . . . . . . . . . . . . . . . . . . . 12-10
3929
7030-04
11
-------
AOC CS-4 RECORD OF DECISION
MASSACHUSETTS MILITARY RESERVATION'
TABLE OF CONTENTS
( continued)
Section
Title
Page No.
123 THE SELECTED INTERIM REMEDIAL AcrION IS COST-
EFFECIlVE ......................;................ 12-11
12.4 THE SELECTED INTERIM REMEDY UTILI7F'S PERMANENT
SOLUTIONS AND ALTERNATIVE TREATMENT OR REsOURCE
RECOVERY TECHNOLOGIES TO THE MAxIMuM EXTENT
PRAcrICABLE .................................... 12-12
12.5 THE SELECTED' INTERIM REMEDY SATISFIES THE
PREFERENCE FOR TREATMENT WHICH PERMANENTLY AND
SIGNIFICANTLY REDUCES. THE MOBILITY, TOXICITY, OR
VOLUME OF THE HAzARDOUS SUBSTANCES AS A PRINCIPAL
ELEMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-13
13.0 DOCUMENTATION OF NO SIGNIFICANT CHANGES........ 13-1
14.0 STATE ROLE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 14-1
GLOSSARY OF ACRONYMS AND ABBREVIATIONS
REFERENCES
APPENDICES
APPENDIX A - Administrative Record Index
APPENDIX B - State Concurrence Letter
APPENDIX C - Public Hearing Transcript
APPENDIX D - Comment Letters Received During Public Comment Period
APPENDIX E - Responsiveness Summary
3929
7030-04
III
-------
AOC CS-4 RECORD OF DECISION
MASSAcHuSETIS MILITARY RESERVATION
LIST OF FIGURES
Fi~re
Title
Pa~e No.
2-1
Si~e Location Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-2
AOC CS-4 Source Location Map. . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-3
2-2
6-1
Soil Organic Analytical Results. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6-2
Additional Soil Analytical Results. . . . . . . . . . . . . . . . . . . . . . . . . .. 6-3
6-2
6-3
AOC CS-4 Groundwater Plume. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6-5
8-1
Screening of Remedial Technologies. . . . . . . . . . . . . . . . . . . . . . . .. 8-3
11-1 Preferred Alternative ,Layout. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11-4
11-2 Groundwater Extraction and Carbon Treatment System. . . . . . . . .. 11-5
11-3 Two-Vessel Granular Carbon Adsorption System. . . . . . . . . . . . . .. 11- 7
3929
7030-04
-------
Table
6-1
6-2
6-3
6-4
6-5
7-1
7-2
7-3
11-1
12-1
12-2
AOC CS-4 RECORD OF DECISION
MASSACHUSETTS MILITARY RESERVATION
LIST OF TABLES
Title
Pa2e No.
Summary of AEHA Groundwater Analytical Data. . . . . . . . . . . . . .. 6-6
Task 2-3B Source Area Groundwater Analytical Data Summary. . . .. 6-7
Task 2-5B Source Area Groundwater Analytical Data Summary. . . .. 6-8
Task 2-3A Downgradient Groundwater Analytical Data Summary. . .. 6-9
MW-603 Study Groundwater Analytical Data Summary. . . . . . . . .. 6-10
Contaminant Concentrations Detected in Groundwater. . . . . . . . . .. 7-3
Summary of Risks Resulting from Exposure to Groundwater
Contaminants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 7-5
Contaminant Concentrations and Federal Maximum Contaminant Levels7-6
Proposed Treatment Levels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11-2
Location-specific ARARs, Criteria, Advisories, and Guidance. . . . .. 12-4
Chemical-spe~c ARARs, Criteria, Advisories, and Guidance. . . .. 12-5
12-3 Action.;specific Applicable or Relevant and Appropriate
Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 12-7
3929
7030-04
-------
SECTION 1
1.0 DECLARATION FOR THE RECORD OF DECISION
SITE NAME AND LOCATION
The Massachusetts Military Reservation (MMR) on Cape Cod, Massachusetts, lies within
the boundaries of Falmouth, Mashpee, Sandwich, and Bourne. The Area of
Contamination (AOC) Chemical Spill Area No.4 (CS4) source area is located 1.1 miles
from the southern MMR boundary on .the northwestern side of West Truck Road. The
AOC CS-4 groundwater plume extends approximately 11,000 feet from the source area.
STATEMENT OF BASIS AND PURPOSE
This document presents the selected interim remedial action for MMR AOC CS-4
groundwater chosen in accordance with the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) of 1980, as amended by the Superfund
Amendments and Reauthorization Act of 1986 and, to the extent practicable, the National
Contingency Plan (NCP). This decision is based on the administrative record file for this
site, which was developed in accordance with Section 113(k) of CERCLA and which is
available for public review at the information repositories located at (1) the Falmouth
Public Library, Falmouth, Massachusetts; (2) the Air National Guard (ANG)
Environmental Management Office at Otis ANG Base, Massachusetts; and (3) the U.S.
Environmental Protection Agency (USEPA) Regional Office at 90 Canal Street, Boston,
Massachusetts. The attached index identifies the items comprising the Administrative
Record upon which the selection of a remedial action is based (see Appendix A). The
Commonwealth of Massachusetts statement of concurrence with the selected remedy is
presented in Appendix B.
ASSESSMENT OF AOC CS-4 GROUNDWATER
Actual or threatened releases of hazardous substances from this AOe, if not addressed
by implementing the response action selected in this Record of Decision (ROD), may
pose an imminent and substantial endangerment to human health, welfare, or the
environment. .
. DESCRIPTION OF THE SELECTED INTERIM REMEDY
Installation Restoration Program
WOO3929.080
1-1
-------
SECTION 1
In summary, the interim remedy consists of the following:
.
extracting contaminated groundwater at the leading edge of the plume
.
pumping the extracted groundwater to a treatment plant
.
removing volatile organic compounds (VOC) by carbon adsorption
treatment
.
discharging treated groundwater to an infiltration trench located
crossgradient at MMR
.
installing observation wells to monitor the hydraulic performance of the
extraction system
.
installing groundwater monitoring wells upgradient of the discharge area
.
sampling existing monitoring wells, monitoring wells to be installed
upgradient of the discharge area, and some of the proposed observation
wells to monitor the plume's flowpath and chemical concentrations
.
monitoring the influent and effluent of the carbon adsorption treatment
.
reviewing the site after five years of operation
This operable unit interim remedial action will intercept the AOC CS-4 groundwater
plume to prevent further downgradient migration of the contaminants. Extraction and
treatment will continue until the final remedy for the site is chosen. Selection of a final
remedy will depend on the study of the AOC CS-I0 groundwater plume that has been
identified upgradient from the AOC CS-4 plume. The interim and fmal remedies must
be consistent with the clean-up goals established for the entire MMR site. The National
Guard Bureau (NGB) long-term clean-up goals for reducing contamination in the
groundwater at MMR are to. meet federal Maximum Contaminant Levels (MCLs), federal
Maximum Contaminant Level Goals (MCLGs), Massachusetts MCLs, or risk-based
guidance levels for compounds for which drinking water standards have not been set.
Installation Restoration Program
WOO3929.080
1-2
-------
SECTION.!
STATUTORY DETERMINATIONS
The interim action is protective of human health and the environment, complies with
federal and state Applicable or Relevant and Appropriate Requirements (ARARs) for this
. limited scope action, and is cost-effective. Although this interim action is Dot intended
to fully address the statutory mandate for pennanen~ and ~tment to the maximum
extent practicable, this interim action uses treatment and thus is in furtherance of that
statutory mandate. B-n~ this action does not constitute the final remedy for the AOC'
CS-4 groundwater, the stalUtory preference for remedies that employ treatment'that
reduces mobility, toxicity, or volume as a principal element, although .partiaDy addressed
in this remedy, will be addressed by the final response actiOD. Subsequent actions are
planned to fully address the threats posed by conditions at this operable unit Because
this remedy will result in hazardous substances remaining on-site above health-based
levels, a review will be conducted to ensure that the remedy continues to provide
, adequate protection of human health and the environment within five years after
commencement of ~e remedial action. Because this is an interim action ROD, review
of this site and this remedy will be continuing as. the NGB continues to develop' final.
remedial alternatives for the AOC ~-4 groundwater. operable uniL., ' . .
The foregoing represents the selection of an interim remedial action by the Department- .
of Defense, NGB, and USEPA Region I, with concurrence of the Commonwealth of, "
Massachusetts.
..
Departme~,,~
By: ~..A, ~~~
Ronald Watson, P.E.
Chief, Environmental Division
Date: ~? 2~ 472....
u.S. En~.', mnental Protection Agency, Region I
I) . /1
By: ......--z d.c...e /~ edJ~ Date:
/'-1Ulie Belaga ~
.' Regional Administrator
'L/' .
4-; ;J.. 0, / 'i f 2-
Installation Restoration Program
3929
1-3
7030.04
-------
SECfION 2
2.0 SITE NAME, LOCATION, AND DESCRIPTION
MMR is a National Priorities Ust (NPL) Superfund site. There are currently
77 areas within MMR that are under investigation. Some of these areas have been
grouped into medium-specific operable units for remediation pUrposes. This ROD
relates to the interim remedial action for the AOC CS-4 groundwater plume, which
was the result of past contamination from AOC CS-4.
. MMR, which lies within the boundaries of Bourne, Falmouth, Mashpee, and
Sandwich, Massachusetts, occupies approximately 22,000 acres (Figure 2-1) and
consists of several cooperating command units: ANG, Army National Guard, U.S.
Air Force (USAF), Veterans Administration, and U.S. Coast Guard. The site is
described in more detail in the focused feasibility study (FFS). The USAF managed
the base until 1973, when base management was transferred to the ANG.
The U.S. Department of Defense (DOD) initiated a multiphase Installation
Restoration Program (IRP) to identify and evaluate problems associated with past
hazardous waste disposal and spills at DOD installations, including ANG facilities.
The NGB is proposing an interim remedial plan, referred to as a preferred
alternative, to address AOC CS-4 groundwater contamination (Figure 2-2). This
ROD recommends a method of addressing contamination associated with AOC CS-4
groundwater from the containment options evaluated during the FFS
(ABB Environmental Services, Inc., 1992a).
Property usage surrounding MMR is primarily residential and light industrial in each
of the surrounding towns. .
Installation Restoration Program
WOO3929.0SO
2-1
-------
o
NOT TO SCALE
7001-05
ji It It ABS
~,.... S En.vironmental
-- erv.ces.lnc.
INSTAL.l.ATION
MASSACHusE IlES'TOAATION
TT1i _ITAlty I'fIOGRAM
IlUEJlYATION
SfTE LOCATION MAP
AOC
CS-4
ROD
FIGURE 2-1
-------
. II
0.. 1/ '.
'f-- 'i "
~~w'r jl
1:1 /f':
/~ J/.".
'~I"::" ..::\\" : I
~::..-- '0
....", ;, ';': .
~J8f11:' " :
. "-'
-
- -
SOURCE: USGS QUADRANGLE.
POCASSET, MA.,
7.S MINUTE SERIES
NOTE: CS = CHEMICAL SPILL
SCALE IN FEET
.
2.000
ABB Environmental
Services Inc.
AOC CS-4
SOURCE LOCATION MAP
I
o
7030-04
I
4.000
IHSTALl..ATION REr.'~ATIOH ~AM
MASSACHUSETTS IlllUTARY RESERVATION
AOC CS-4
ROD
FIGURE 2-2
-------
SECI10N 3
3.0 SITE HISTORY AND ENFORCEMENT ACTMTlES
In accordance with Section 117(a) of CERClA, the NGB is publishing this ROD to
address public review and comment on the selected interim containment alternative,
known as a remedial alternative, considered for AOC CS-4 as the interim remedy.
The NGB, in consultation with USEPA, considered public comments as part of the
final decision-making process for selecting the remedy for AOC CS-4 groundwater.
This ROD summarizes results and conclusions of the FFS and the Proposed Plan.
In response to environmental contamination that has occurred as a result of the use,
handling, storage, or disposal of hazardous materials at many military installations
across the United States, the DOD initiated invesngation and clean-up activities
und~r the IRP. The IRP parallels the Superfund program and is conducted in the
following seven stages: ..
8
identification of potential hazardous waste sites
confinnation of the presence of hazardous materials at the site
determination of the type and extent of contamination
evaluation of alternatives for clean up of the site in the FFS
proposal of a clean-up remedy in the Proposed Plan
selection of a remedy
implementation of the remedy for clean up of the site
.8
8
8
8
8
8
Both private sector and federal facility sites are eligible for placement on the USEP A
NPL, which is used to prioritize investigations and responses at hazardous waste sites.
MMR was added to the NPL on November 21, 1989. Private sector sites placed on
the NPL are eligible to receive funding from the nation's environmental trust fund
(i.e., Superfund), and are often called Superfund sites. Federal military facilities such
as MMR receive - funding from the DOD Defense Environmental Restoration
Account.
3.1 LAND USE AND RESPONSE HISTORY
AOC CS-4 was operated for the maintenance of military vehicles by the U.S. Army
from 1940 to 1946 and by the USAF from 1955 to 1973. Wastes generated and
Installation Restoration Program
WOO3929.080
3-1
-------
SECI'lON 3
potentially spilled or dumped during this period include oils, solvents, antifreeze,
battery electrolytes, paint, and waste fuels.
In addition to motor pool activities, the base Defense Property Disposal Office
(DPDO) maintained a storage yard in the northern portion of AOC CS-4 between
1965 and 1983. Wastes were transported to the DPDO'from shops and laboratories
operating at MMR. Wastes and equipment handled at AOC CS-4 included
transformers, electrical equipment, waste oils, solvents, and waste fuels. liquid
wastes were stored in co~tainers or tanks in an unbermed area, or deposited in six
S,OOO-gallon underground storage tanks (USTs) installed to store motor gasoline
when the motor pools were operational. The USTs were used until January 1984; .
in September 1984, the last USTs used for waste storage were emptied and removed.
The area has been inactive since 1986.
Since January 1986, several site investigations have been conducted at MMR as part
of the IRP. Initially, AOC CS-4 was studied by the U.S. Army Environmental
Hygiene Agency (AEHA) to assess the impact of base DPDO activities on local
groundwater quality. Results of that study prompted AEHA to include the remaining
motor pool area in the investigation. AOe CS-4 was further investigated in the
preliminary assessment of MMR in 1986, and again in 1988 (E.C. Jordan Co., 1986
and 1990a). .
In 1987, several multilevel monitoring wells were installed along the MMR boundary,
including monitoring well cluster MW-603. Data obtained from these investigations
suggest that contaminated groundwater may be migrating off MMR from some of the
sites. In particular, groundwater contamination may migrate off MMR in a south-
southwesterly direction from AOC CS-4, as indicated by monitoring well cluster
MW-603, located along the southern MMR boundary.
The 1989 Phase I MW-603 groundwater study was conducted to determine the extent
of groundwater contamination detected in the MW-603 cluster, primarily
tetrachloroethylene (PCE), trichloroethylene (TCE), and 1,2-dichloroethylene (DCE),
and to provide more data to link AOe CS-4 with contaminants in MW-603. This
study concluded that chlorinated solvents were associated with soil contamination
found at the AOe CS-4 source area and had migrated off-MMR toward potential
groundwater receptors (E.C. Jordan Co., 1990c).
Installation Restoration Program
WOO3929.080
3-2
-------
SECTION 3
Phase I of the MW -603 groundwater study determined the extent of groundwater
contamination and identified the source area. Phase I also identified the need for
better hydrogeologic data to assess the feasibility of remediating the groundwater
plume. Conducted in the spring of 1990, Phase n of the MW-603 groundwater study
was an aquifer pumping test to gather these hydrogeologic data (E.C. Jordan Co.,
1990b). .Using these hydrogeologic data, the FFS was prepared to evaluate the
interim remedial alternatives for containing the AOC CS-4 groundwater plume.
3.2 ENFORCEMENT HISTORY
The NGB has followed USEPA guidelines for most of the IRP investigations
conducted at MMR since 1986 and for all investigations completed since 1989.
Placement on the NPL has not necessitated substantive changes in the overall
technical approach to remediation studies. However, upon form~ 117.ation of the NPL
status, the NGB entered into an Interagency Agreement with USEPA and U.S. Coast
Guard on July 17, 1991, to define responsibilities, documentation requirements, and
future regulatory interaction regarding remedial activities at MMR under CERCLA
authority. The ANG is the NGB component directly responsible for carrYing out
NGB's responsibilities under the agreement.
Installation Restoration Program
WOO3929.080
3-3
7030-04
-------
SECI'ION 4
4.0 COMMUNITY PARTICIPATION
Throughout MMR's history, community concern and involvement has been high. The
NGB and USEP A have kept the community and other interested parties apprised of
site activities through informational meetings, fact sheets, press releases, public
hearings, and Technical Environmental Affairs Committee (TEAC) meetingS. The
TEAC was organized in 1986 by NGB to provide a forum for public input on MMR
remedial response activities. Membership on the TEAC comprises USEP A,
Massachusetts Department of Environmental Protection (MADEP), and
representatives from local, regional, and state groups.
During July 1991, the MMR community relations plan was released; this outlined a
program to address community concerns and keep citizens informed about and
involved in activities during remedial activities. On February 24, 1992, the NGB .held
an informational meeting at Lawrence Junior High School in Falmouth,
Massachusetts, to describe the FFS and Proposed Plan.
On February 24, 1992, the NGB made the administrative record available for public
review at NGB's IRP Office, Otis ANG Base, Massachusetts; USEP A's offices in
Boston, Massachusetts; and the Falmouth Public Library, Falmouth, Massachusetts.
The NGB published a notice and brief analysis of the Proposed Plan in the Cape Cod
Times, Bourne Courier, and Sandwich Broadsider on February 20, 1992, and in the
Falmouth Enterprise and Mashpee Enterprise on February 21, 1992. The NGB made
the FFS and Proposed Plan available to the public at Falmouth Public Library and
the administrative records locations.
On February 24, 1992, the NGB held an informational meeting to discuss the results
of the field investigations and the clean-up alternatives presented in the FFS and to
present the Proposed Plan. Also during this meeting,. the NGB answered questions
from the public. From February 25 to March 25, 1992, the NGB held a 3D-day
public comment period to accept public comments on the alternatives presented in
the FFS and the Proposed Plan. On March 18, 1992, the NGB held a public hearing
to discuss the Proposed Plan and to accept any oral comments. A transcript of this
hearing, the written comments received, and the NGB's responses to the comments
are included in the responsiveness summary (see Appendices C, D, and E).
Installation Restoration Program
WOO3929.080
4-1
-------
SECI10N 5
5.0 SCOPE AND ROLE OF RESPONSE ACI10N
The selected remedy was developed by combining components of dii!erent
containment alternatives to obtain a comprehensive approach for remediation of
AOC CS-4 groundwater. The selected remedy is an interim remedy. An interim
remedy is designed to take action to protect human health and the environment in
the short term while additional information is collected to better assess the aquifer's
and contaIIiinant's responses to remediation efforts. The interim remedy will operate
. for a minimum of five years, after which time a final remedial action will be
developed. A final ROD for groundwater will be based on the data collected during
the design, operation, and monitoring of the interim remedy and the findings of
further characterization of the CS-IO plume. Additional interim remedial actions
may be proposed if data collected prior to the final ROD warrant it.
In summary, the interim remedy provides for (1) extracting contaminated
groundwater at the leading edge of the CS-4 groundwater plume for a minimum of
five years; (2) pumping the extracted groundwater to a proposed treatment plant to
remove contaminants by carbon adsorption; (3) discharging the treated groundwater
to infiltration trenches located crossgradient from the plume at MMR; (4) installing
observation wells to monitor the hydraulic performance of the extraction system;
(5) sampling existing monitoring wells and some of the proposed observation wells
to monitor the plume's flowpath and contaminant concentrations; (6) monitoring the
influent and effluent of the carbon adsorption treatment; (7) monitoring proposed
monitoring wells upgradient of the discharge area; and (8) reviewing the site after
five years of operation. This operable unit interim remedial action will intercept the
CS-4 groundwater plume to prevent further downgradient migration of contaminants.
An additional contaminated groundwater plume, CS-10, has been identified
. upgradient of the CS-4 plume. The interim remedial action will allow time for the
CS-lO plume to be characterized and a final remedial action to be designed that will
be consistent with the interim action and the NGB's long-term clean-up goals for
reducing. contamination in the groundwater at MMR.
The interim remedial action will address the following objectives:
.
Reduce potential risk associated with ingestion of contaminated
groundwater to acceptable levels.
Installation Restoration Program
WOO3929.080
5-1
-------
SECI'lON 5
.
Protect uncontaminated groundwater and surface water for future use
by minimizing the migration of contaminants. .
.
Reduce the time required for aquifer restoration.
Installation Restoration Program
WOO3929.080
5-2
-------
SECTION 6
6.0 SUMMARY OF SITE CHARACTERISTICS
Section.2.0 of the FFS is an overview of the environmental contamination assessment
. (ABB Environmental Services, Inc., 1992a). The significant findings of the
investigations and environmental contamination assessment are summarized in this
section.
6.1 SOIL CONTAMINATION AsSESSMENT
The primary focus of the environmental contamination assessment is groundwater
contamination at AOC CS4. Because soil contamination has been identified as the
source of groundwater con~nation, soil contamination is reviewed herein. The
. soil contamination' assessment summarizes the results of field work conducted as
Tasks 2-3B and 2-5B during the spring and summer of 1988 and the fall of 1989,
respectively (E.C. Jordan Co., 1990a and 1990d). .
The primary soil coniaminants at AOC CS4 appear to be PeE, TCE, and 1,2-DCE.
Concentrations as high as 130,000 micrograms per kilogram (~g/kg) of PCE and
100,000 ~g/kg of TCE were detected in a layer of silty fill soils along the western
edge of the site. The greatest concentrations are limited to an area approximately
150 by 6 feet (ABB Environmental Services, Inc., 1991). Figures 6-1 and 6-2
illustrate the spatial distribution and extent of contaminants encountered in Aoe
CS-4 source area soils.
To understand the potential for AOC CS-4 soil contamination to leach to
. groundwater, the USEPA Organic Leachate Model (OLM) and modified Summer's
model were utilized (USEPA, 1986 and 1989). The AOCs CS-4, FS-25, and FTA-l
engineering evaluation/cost analysis (EE/CA) report discusses the modeling analysis,
which indicates that leaching from AOC CS-4 soil would be expected to impact
groundwater as observed at the sites (ABB Environmental Services, Inc., 1991).
The source of groundwater contamination appears to be residual chemicals in soils
. at AOC CS-4. Evaluation of the leaching potential of these soils using the OLM
suggests that concentrations in soils at the source area are sufficient to produce the
Installation Restoration Program
WOO3929.080
6-1
-------
- - ":' ':'1 II
~., tr1t c:s G. ~+
-------
SURFACE
I
; I If:i
. r I!:2
i:
I.
I
ETHYLSENZENE
TETRACHLOROETHYLENE
TOLUENE
TRICHLOROETHYLENE
XYLENES
" 2 - DICHLOROeTHYLENE
j ~ TOTALSVOC.
"-~
83
2,9OOD
28
9,8OOD
4,9OOD
22,OOOD
-. _._.--. - - . .
H:
.
/
I!:IA
1,2 - DICHLOROETHYLENE
TRICHLOROETHYLENE
TETRACHLOROETHYLENE
TOTAL SVOC.
PESTICIDES
I!:2A
1.I:2Z
iL
..- ". .
1,2 - OICHLOROETHYLENE
'TRICHLOROETHYLENE
: TETRACHLOROETHYLENE
: XYLENES
i TOTAL SVOC.
PESTlCIDESIPCBs
9,800
65,000
9,000
1.2:U
32,000
1oo,oooD
130,0000
3,300
,-~
j
j
-1
WOODED KETTLE
NO VISUAL EVIDENCE OF CONTAMINATION
NO SAMPLES SUBMITTED FOR ANALYSIS
TP-7A TP-8A
II!:1 K 3-5" iDUP
ETHYLBEN'ZEHE NA ~.
TOLUENE NA 31110
1,1,1 -TRICHLOROETHYLENE NA 131-
XYLENEs NA 44OBE/1:ID
TOTAL SVOCe I5IU .74OJJS5DD
..4'.oOT 41
",4'.000 7100C111DDC
NOTES:
i TASK 2.38 TEST PITS, JANUARY 1111
TASK 2.38 TEST PITS, MAY "88
WATER TABLE MONTORING WELL
~ . . EXISTWQ FENCE
'-".- DRA"AGE
---1 HlLLSLoPe
D RESUlT OF Dl..UTION ANALYSIS
NOT DETECTED
RESULTS IN ug/kg
* NO PARAMETERS
DETECTED IN SAMPLE
SCALE IN FEET
I
50
I
o
J
100
7001.05
""".. . . -........- ~ .
j~ 1'1' ASS Environmental
r,.... Services. Inc.
ASIA --III
'Paved DPDO Yard
o
u
12
15
87
ADDITIONAL
SOIL ANALYTICAL RESULTS
. ..
INSTA~TION RESTORATION PROGRAM
MASSACHusETTS -.rTARY RESERVATION
AOC
CS-4
ROD
6-3
FIGURE 6-2
-------
SECI'lON 6
observed groundwater contamination. Remediation of the AOC CS-4 source area
is the subject of a separate document (ABB Environmental Services, Inc., 1991).
6.2 . GROUNDWATER CONTAMINATION AsSESSMENT
The groundwater contamination assessment discusses results of investigations that
began in 1985 with the AEHA and continued until 1990 with ABB Environmental
Services, Inc. The study of groundwater related to AOC CS-4 evolved from two
studies. Groundwater at AOC CS-4 was investigated as part of Tasks 2-3A and 2-3B
and Phases I and n of the MW-603 groundwater study (E.C. Jordan Co., 1989a,
1990a, 1990b, and 199Oc). The Phase I MW-603 groundwater study provided the link
between the downgr~dient groundwater plume and the AOC CS-4 source area.
A profile of the AOCCS-4 groundwater operable unit plume was generated from
data gathered during the investigative studies. Figure 6-3 illustrates the horizontal
extent of groundwater contamination. The area where contaminant concentrations
exceed 5 micrograms per liter (J£g/L) extends from beneath AOC CS-4, 11,000 feet
downgradient to within 1,200 feet north of Route 151. The lateral width of the CS-4
groundwater operable unit is approximately 800 feet; its thickness in profile is
approximately 40 feet. The estimated plume volume with concentrations equal to or
greater than 5 p.g/L is 790 million gallons (assuming 30 percent aquifer porosity).
The plume is located near the water table at AOC CS-4. Influenced by rainfall
accretion, the plume moves deeper into the aquifer with distance from the source.
At MW-603, the plume is approximately 75 feet below the water table. At MW-1206,
where only trace concentrations are detectable, the plume is estimated to be 85 feet
below the water table.
The primary chemicals detected in the CS-4 groundwater operable unit are PCE (at
concentrations up to 62 p.g/L) and TCE (at concentrations up to 32 p.g/L). DCE has
been detected in groundwater at the AOC CS-4 source area at concentrations up to
26 p.g/L.. 1,1,2,2-Tetrachloroethane has been detected at concentrations as high as
24 p.g/L in downgradient monitoring wells. Tables 6-1 through 6-5 summarize results
of the groundwater investigations as presented in the FFS.
Installation Restoration Program
WOO3929.0SO
6-4
-------
!
ESTIMATED LOCATION OF
,.5 wg/L TCE + PCE CONCENTRATION
INSTALunON IIESTOIIAnON 'IIoallAIi
IIASIACHUSEnS "UTA"" IIESER'tAnON
IAII MAl' SOWIct: USGS MAl'S
I'OCASIIT. MASS. DAltO INJ ,_....,.., 11111 .
'.LIIOU'K. MASS. DATED .." c~..._.... ""}
7oa'.05 .
SCAU II FtET
.
1.000
I
2.000
n 1'1' ABB Environmental
,...... Services Inc.
MEA ..,.. 8O'WI1III
f.-~
AOC
CS."
ROD
AOC cs."
GROUNDWATER PLUME
-------
TA8LE 8-1
SUMMARY OF AEHA GROtJM)WATBI ANALYTICAL DATA
AOC CS-4 GROUNDWATER RecoRD OF DECISION
MASSACHUSETT8 MIJTARY RE8BIVATION
ANALY-
MOMTORINO
WEll Nmm.
ARSENIC BORON BARIUM CALCIUM CADMIUM IRON POTA88IUII MAONEllUilll MANOANE8E SODIUM NICKel ZINC NnMTE PHENOt
AEHA-6 - - - 2100 13 142 - 1870 221 5100 - 41 180 -
AEHA-7 31* 112* 29* 8.000* - 2300 840 3 120* 599* 10500* - 42* 1.800* -
AEHA-8 - 86 12 3070 - 3 500* 1 120* 2770 572 7100 86 21 - 10*
RANGE ND-31 ND-112 ND-29 ND-B 000 ND-13 142-3.500 ND-112O 1.870-3 120 221-599 5100-1050 ND-86 21-42 ND-1 BOO ND-10
MCLs 5 - 1,000 - 10 - - - - - - - 10,000 -
~
Note.:
-,
All values reported as micrograms per liter (pg/l).
Modified after AEHA (1986) -
- = Not Detected -
* Highest Detection
ND Non-Detect
AEHA U.S. "'my Environmental Hygiene Agency
MCl Maximum Contaminant leVeT
0\
~ Source: AEHA. 1986
-------
TABLE 6-2
TASK 2-38 SOURCE AREA GROUNDWATER ANAlnJCAl DATA SUMMARY
AOC CS-4 GROUNDWATER RECORD OF DECISION
MASSACHUSETT8 MUTARY RE8ERVATION
'l'
-.J
ANAL V..
MONITORINO TARGET COMPOUND LIST VOLATl.E OIIGANIC COMP0UND8 T AIIOET ANALY'JE I.I8T INOIIGANIC8
WB.l 1.2-DICHlOROE"I'ttYtSE (TOTALI
TETRACHlORO£THYlENE TIICHLOROE1'HYlENE .8~
AEHA-6 - - - -
AEHA-7 - - - -
AEHA-8 - - - -
MW-1 - - - -
MW.2 - - - 8.630E
MW-3 19 4E 6 7,99OE
MW.4 5 - - 9,14OE
MW-5 8 - - -
MW-8 4E - - 8,36OE
MW-9 - - - 5,24OE
MW-10 - - - 15,100E*
MW-11 37* 26* 23* -
RANGE ND-37 ND-26 No.23 ND-15,100E
Not..:
All values reported In micrograms per liter (pg/L)
E Estimated Concentration
Not Detected
ND Non-Detect.
* Highest Site Detection 01 Analyte
Sampling Date: 3/90 to 4/90
Semlvolatlle organic compounds were not detected.
Source: E.C. Jordan Co., 19908.
-------
T AILE 6-3 .
TA8K 2-6B-8OURCE AIIEA GIIOUNDWATER ANALVT1CAL DATA SUMMAIIY
Aoe CS~ GIIOUNDWATER REcOtlD OF DECISION
MA88ACHU8ETT& MIUTAIIY RESERVATION
ANALY811
MTOIIIWO TOTAL COMPOUND IJcT VOLATU ORGANIC COMPOUNDS TOTALSVOca
WEU.
1~2..oICHLOII~
TEnlACtf.ollOETHVLENE . (TOTAL TIIICHLOIIOETHVLENE 1 1.2.2:rEnlACtf.OIlOETHANE 118C2-ETHY1HExYLJPHTHALA TE
-!M! - - - - -
..U~.7 Itl - - - -
-iA.A 1J - - - -
1.1 /
- - - - -
I.? - - - - -
J.'a Q 1 'a - -
1-4 4 - - - -
'i.rr. II - - - -
1..11. ~ - - - 1?
I.Q - - - - -
I.QA - - - - -
I.m - - - - -
1-11 ~* ?1* ~* - 1S*
'.1? - - 1 - -
1.13 1 - 1 - -
I..MI.?'? - - - - -
I.F.n'ali. ~n* - ?I'f* ~ -
I-"n~B - - - 1n -
I..MI.1C - - - - -
I-"n~n - - - - -
1-61'131; . - - - - -
II,IGE No.sa No.21 NO.3/') No.22 No.15
,.:
alues reported in micrograms per liter (pg/L)
= Concentration leIS the Contract Required Detection Umit
Not Detected
Highest Site Detection of Analyte
Non-Detect .
Semivolatile Organic .Compound
=
IC
w003929.T80/5
-------
TAILE 8.4
TASK 2-3A DOWNORADIENT GROUNDWATER ANALYTICAL DATA SUMMARY
Aoe eS-4 GROUNDWATER RECORD OF DECISION
MASSACHUSETTI MIJTARY RE8BIVATION
'7'
\0
ANAL Y818 ..
MONITORINO WEll TARGET COMI'OUM) LIST VOtATIlE.ORGANIC CO~P0UND8
IDA TE SAMPlED. TRIC...OIIOETHYlENE TETRAC...OROETHYlENE ETHYlIENZENE
1.1.2.2; TETRAc.-.OIIOETHANE XYlENE8
MW.603A 10/27/87 31 61* 23 - -
1/5/88 32* 57 24* - -
MW-603B 10/27/87 7.8 12 12 - -
1/5/88 6 11 9 - -
MW-603C/OUP 10/27/87 -/- JjJ J/J -/- -1-
{
1/5/88 -/- J/- J/- -1- . ( -1-
o
IRP-9/0UP 10/27/87 -1- -/J -1- -1- -/J
1/5/88 -1- -1- -/- -1- [ J/-
MW-603E 10/27/87 - - - - -
.'
1/5/88 - - - J .. 7*
'
RANGE No.32 N0-61 No.24 - ~ ~ NO.7
MCls 5 5 - 700 10,000
Note.:
NO Non.Detect
All values reported In micrograms per liter (pg/l)
* Highest Detection
J Concentration less than Contract Required Detection Umlt
Not detected
Maximum Contaminant level
MCl
Source: E.C. Jordan Co., 19898
.'
-------
T A8LE 6-6
MW-803 STUDY GROUNDWATER ANAlYTICAL DATA SUMMAfIY
AOC' CS-4 GROUNDWATER RECORD OF DECISION
. MA88ACHUSETTS MIUTAfIY RE8ERVA11ON
.ANAlY88
MONITOIIIWG WELl. TARGET COMI'OUND U8T VOLATU ORGANIC COMPOUNDS TARGET ANALYn LIsT 1NoRGAN1C5
TRlCH.OROEfMYLBIfE TETMCHLORonHYLENE 1.1.2.2- TETMCH.OROETHAfIE SODIUM . CAI.CIUII
MW-1201A - - - - -
MW-1201B - - - - -
MW.1202A 24 62" - - -
MW.1202B 5 18 4 - -
MW.1203A - - - - -
MW.1204A/DUP 3/1 13/6 - 11,500-/10.800 -
MW.1204B - - - - -
MW.12DSB - - - - -
MW-1205C 2 2 - - -
MW.1205D/DUP 14/13 14/13 5/S 9.210/8,480 5.24O-/S.22O
MW.1206Z - - - - -
MW-1206A 1 2 - - -
MW.1206B - - - - -
MW-1206C - - - - -
MW-1207A - - - - -
MW-1208A 2 3 1 - -
MW.1209A - - - - -
MW-1210A - - - - -
MW-1212A - - - - -
MW-1212B - - - - -
MW-603Z - - - - -
MW-6Q3A/DUP 30-/14 53D/31 1S-{7 . 9,090 -
MW-603B S 13 10 - -
RANGE ND-3O ND-62 ND-1S ND-1 1 ,500. ND-5.240
110188: .
~I-values reported in micrograms per liter (pg/L)
. Highest Detection .of Analyte
Not Detected
Non.Detect
~D
~ource:
E.C. Jordan Co., 1990c
WOO3929.T80/8
6-10
-------
SECI10N 6
The CS-4 groundwater operable- -unit will continue to migrate downgradient from its
1989 position at a rate of approximately 370 feet per year (ft/yr). This flow rate is
equivalent to approximately 50 gallons per minute (gpm) across the 800-by-4O-foot
cross-sectional area of the plume. The 790 million gallons of water in the plume
would require an estimated 30 years (based on the base plume flux) to pass the
current location of the downgradient plume edge.
Installation Restoration Program
WOO3929.080
6-11
-------
SECI10N 7
7.0 SUMMARY OF SITE RISKS
A human health risk assessment was conducted to estimate the probability and
magnitUde of potential adverse human health effects from exposure to contaminants
associated with AOe eS-4. Environmental risk does not currently exist from
contaminants in groundwater from AOe eS-4. Environmental risks would only be
possible if the contaminated groundwater were allowed to migrate farther south and
discharge into eoonamessett Pond. Because groundwater will be remediated before
it reaches the pond, there would be no impact by AOe CS-4 groundwater to that
surface water body. An ecological risk assessment was not conducted for AOe eS-4.
However, once the extent of the AOC eS-lO plume has been characterized, an
ecological risk assessment could be conducted for both groundwater plumes. The
groundwater risk assessment is described in detail in the FFS (ABB Environmental
Services, Inc., 1992a). The human health risk assessment followed a four-step
process: .
1.
Contaminant identification, which identified those hazardous
s\1bstances that, 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 e~osure.
3.
Toxicity assessment, which considered the types and magnitUde of
adverse health effects associated with exposure to hazardous
substances.
4.
. Risk characterization, which integrated the three earlier steps to
summarize the potential and actual carcinogenic and noncarcinogenic
risks posed by hazardous substances at the site.
Results of the human health risk assessment for the AOe eS-4 are discussed in the
following paragraphs, followed by the conclusions of the environmental risk
assessment.
Installation Restoration Program
WOO3929.080
7-1
-------
SECflON 7
Four contaminants of concern were selected for evaluation in the risk assessment.
All compounds detected at least once in the groundwater, except for 2-butanone,
were retained as contaminants of concern, and are listed in Table 7-1. 2-Butanone
was not selected as a contaminant of concern because it was present in laboratory
blank samples and is not considered to be site-related. The health effects of each
contaminant of concern are summarized in Appendix B of the FFS
(ABB Environmental Services, Inc., 1992a). .
Potential human health effects associated with exposure to the contaminants of
concern were estimated quantitatively through the development of hypothetical
exposure pathways. These pathways were developed to reflect the potential for
exposure to hazardous substances based. on the current and potential future uses and
location of AOC CS-4. The following is a brief summary of the exposure pathways
evaluated; a more thorough description is in the FFS (ABB EnVironmental Services,
Inc., 1992a). The receptor population exposure pathway was assumed to be future
downgradient residents. A lifetime (Le., 70 years) of consuming 2 liters of
groundwater per day for 350 days per year was assumed for an average body weight
of 70 kilograms. It was assumed that the same size person would inhale volatilized
contaminants at a rate of 0.6 cubic meter per hour during daily 12-minute showers.
For each pathway evaluated, an average and a reasonable maximum exposure
estimate was generated corresponding to exposure to the average and the maximum
concentration detected in that particular medium.
Excess lifetime cancer risks were determined for each exposure pathway by
multiplying the. exposure level with the chemical-specific cancer potency factor.
Cancer potency factors have been developed by USEP A from epidemiological or
animal studies to reflect a conservative ''upper bound" of the risk posed by potentially
carcinogenic compounds. That is, the true risk is very unlikely to be greater than the
predicted risk. The resulting risk estimates are expressed in scientific notation as a
probability (e.g., lx10-6 for 1/1,000,000) and indicate (using this example), that an
individual is not likely to have greater than a one-in-a-million chance of developing
cancer over 70 years as a result of site-related exposure as defined to the compound
at the stated concentration. Current USEP A practice considers carcinogenic risks
to be additive when assessing exposure to a mixture of hazardous substances.
The Hazard Index (HI) was also calculated for each pathway as USEP A's measure
of the potential for noncarcinogenic health effects. The m is calculated by dividing
Installation Restoration Program
WOO3929.080
7-2
-------
TABLE 7-1
CONTAMINANT CONCENTRATIONS DETECTED IN GROUNDWATER
AOC CS-4 GROUNDWATER RECORD OF DECISION
MASSACHUSEnS MIUTARY RESERVATION
CHEMICAL LEVEL
CONCENTRATION '
RANGE.
MEANi
FREQUENCY' . .
OF DETECTIoN.
MAXIMUM
DETECTED
CoNCENTRATIOH
Volatile Oraanlc Compounds wall)
Tetrachloroethylene
Trichloroethylene
1,1,2,2-Tetrachloroethane
1,2-Dlchloroethylene (total)4
ND-62 18 14/20 62
ND-32 9.1 14/20 32
ND-24 6.8 11 /20 24
ND-21 1.1 1/20 26
......
I
U)
Not.. :
I Duplicate samples were averaged.
J Arithmetic means were calculated using one-half the Contract Required Quantltatlon Umlt.
J The frequency of detection Is the number of samples In which 8 compound Is detected ove, the number of samples available.
. 1,2-Dlchloroethylene was selected for evaluation due to Its potentlaf to migrate downgradlent of the lOurce..
ND
pg/L
Non-Detect
micrograms per liter
-------
SECfION 7
the exposure level by the reference dose (RID) or other suitable benchmark for
noncarcinogenic health effects. RIDs .have been developed by USEP A to protect
sensitive individuals over the course of a lifetime and they reflect a daily exposure
level that is likely to be without an appreciable risk of an adverse health effect.
RIDs are derived from epidemiological or animal studies and incorporate uncenainty
factors to help ensure that adverse health effects will not occur. The HI is often
expressed as a single value (e.g., 0.3) indicating the ratio of the stated exposilre as
defined to the RID value (in this example, the exposure is approximately one-third
of an acceptable ~osure level for the given compound). The m is only considered
additive for compounds that have the same or similar toxic endpoints (for example:
the HI for a compound known to produce liver damage should. not be added to a
second whose toxic endpoint is kidney damage).
Table.7-2 depicts the carcinogenic and noncarcinogenic risk summary for
contaminated groundwater ingestion and inhalation of volatilized contaminants in. the
shower. More detailed tables of the risk assessment are in Appendix B of the AOC
CS-4 FFS (ABB Environmental Services, Inc., 1992a).
Carcinogenic risks are compared to the USEP A target carcinogenic risk range of 1cr
to 10-6. Noncarcinogenic risks are compared to the USEP A target noncarcinogenic
HI of 1.0 (USEP A, 1990).
Future potential carcinogenic risks for downgradient residents ingesting and inhaling
groundwater contaminants were estimated to be 3xHr' (average case) and 1x1
-------
TABLE 7-2
SUMMARY OF RISKS RESUlTING FROM EXPOSURE
To GROUNDWATER CONTAMINANTS
Aoe CS-4 GROUNDWATER RECORD OF DECISION
MASSACHUSEnS MIUTARY RESERVATION
~
I
VI
.. ..
LIFETIME
, INCREM$ITAl . . .
,
CARCINOGENiC NoNcARciHoGENIC
EXPOSURE locATION EXPOSURE MEDIUM EXPoSURE ROUTE . . RISKi'. . HAZARDINOEK
. .
AVERAGE
Aoe eS-4 Groundwater Ingestion 3X10-5 0.02
Inhalation of
VoIatllzed Contaminants 3X10-6 NA
TOTAL 3x10.5 '.0.02 \
MAXIMUM
AOe eS-4 Groundwater Ingestion , . 9x10-5 0.08
Inhalation of
VoIatllzed Contaminants 1X10.5 i NA
TOTAL 1x10'" 0.08
Note:
NA
Appropriate toxicity Information Is nol available to evaluate this route 0' 8xposure.
-------
TABLE 7-3 ,
CONTAMINANT CONCENTRATIONS AND FEDERAL MAXIMUM CONTAMINANT lEvELs
AOC C5-4 GROUNDWATER RECORD OF DECISION
MAssACHUSETTS MILITARY RESERVATION
,.,
.' ,MAxIIuI,/
'MEAN CONCENTRATION 'CoNcEN'rRATION FEDERALMCL
CHEMICAl. ,'.. (POlL) . ,',. ' , '., (paIL) CP9/l)
Tetrachloroethylene 18 62 5
Trichloroethylene 9.1 32 5
1,1,2,2-Trichloroethane 6.8 24 NA
1 ,2-Dlchloroethylene (total) 1.1 26 70'
Not88:
NA
,
.
Not Available
MCL is for the cia-llOmer
micrograms per liter
.
pg/L
.
WOO3929.TSO/10
-------
SEctION 7
and substantial endangerment to human health, welfare, or the environment. Risks
due to groundwater releases are dealt. with in this ROD. .
Installation Restoration Program
WOO3929.080
7-7
-------
SECI10N 8
8.0 DEVELOPMENT AND SCREENING OF ALTERNATIVES
Four alternatives were developed and screened in the FFS. This section describes
the response objectives and the development and screening of alternatives.
8.1 STATIJTORY REQUlREMENTSjRESPONSE OBJECl'lVES
Under its legal authorities, NGB's primary responsibility at this NPL site is to
. undenake remedial actions that are protective of human health and the environment.
In addition, Section Ul 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 limitations, unless a waiver is invoked; a requirement that
the selected remedial action is cost-effective and utilizes permanent solutions and
alternative treatment technologies or resource recovery technologies to the maximum
extent practicable; and a preference for remedies in which treatment that
permanently and significantly reduces the mobility, toxicity, or volume of the
hazardous substances is a principal element over remedies not involving such
treatment. Response alternatives were developed to be consistent with these
Congressional mandates.
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 interim
remedial action objectives were developed to mitigate existing and future potential
threats to human health and the environment:
.
Reduce the potential risk associated with ingestion of contaminated
. groundwater to acceptable levels.
.
Protect uncontaminated groundwater and surface water for future use
by minimizing the migration of contaminants.
.
Reduce the time required for aquifer restoration.
Installation Restoration Program
WOO3929.080
8-1
-------
SECTION 8
8.2 ALTERNATIVES DEVELOPMENT AND SCREENING
CERClA and the NCP set forth the process by which remedial aCtions are evaluated
and selected. In accordance with these requirements, a range of alternatives was
developed for AOC CS-4 groundwater plume containment.
. With respect to the groundwater response action, theFFS developed a no action
alternative and a limited number of interim remedial alternatives that attain site-
specific remediation levels using different technologies (ABB Environmental Services,
Inc., 1992a). . .. .
Section 5.0 of the FFS identified, assessed, and screened technologies based on
implementability, effectiveness, and cost. The FFS focused only on groundwater
contaminant migration technologies. A separate report addresses source control
technologies (ABB Environmental Services, Inc., 1991). Section 6.0 of the FFS
presented the interim remedial alternatives developed by combining the technologies
identified in the initial screening process per SeCtion 300.430(e)(3) of the NCP. The
purpose of the initial screening was to narrow the number of potential remedial
actions for further detailed analysis while preserving a range of options. Each
alternative was then evaluated and screened in Section 7.0 of the FFS.
Of the 13 remedial technologies screened in the FFS, five. were retained for detailed
analysis. Figure 8-1 identifies the five technologies retained through the screening
process, as well as those eliminated from further consideration.
Installation Restoration Program
WOO3929.080
8-2
-------
CONTAINMENT
VERTICAL
EXTRACTION
WELLS
(:!:::::rH:::':::Q::'::=~~lt:::::::!::::m:!:!r
..
.-
)()
,
.J
. .
LEGEND
1...:..,.:,.:.;..::.:.::::::::::.j::.:.::::I:'...:::::,.j:::.1 -::~~;:::o~lmlnated from Further
9201043D
TREATMENT
CARBON
ADSORPTION
AIR STRIPPING
~
UV/OXIDATION
DISCHARGE
CROSSGRADIENT
DISCHARGE
".-
-
. i~i.811'lltllllll:
: '
Ml II II ABB Environmental
........ Services, Inc.
AlIA IADWNIOVEIi
INSTAlLATION RESTORATION PROGRAM'
aMSSAa-tUSETTS MLITARY RESERVATION
SCREENING OF REMEDIAL
TECHNOLOGIES
AOC
C8-4
ROD
-------
SECI'ION 9
9.0 DESCRIPTION OF ALTERNATIVES
. . .
This section provides a narrative summary of each alternative evaluated. A detailed
tabular assessment of each alternative is in Table 8-1 of the FFS
(ABB Environmental Services, Inc~, 1992a).
No source control alternatives were studied in the AOC CS-4 groundwater FFS.
Details of the source area removal action are discussed in the AOCs CS-4, FS-25,
and FTA-1 source EE/CA (ABB Environmental Services, Inc., 1991). -.
9.1 CONTAINMENT ALTERNATIVES ANALnED
Containment alternatives address contaminants that have migrated from the original
source of contamination. At AOC CS-4, contaminants have migrated in a
south-southwesterly direction from the AOC CS-4 site at an estimated rate of
370 ft/yr. The alternatives evaluated for AOe eS-4 are a minimal no-action
alternative (GW-l); a vertical extraction system. activated carbon treatment, and
discharge alternative (GW-2); a vertical extraction system, air-stripping treatment,
and discharge alternative (GW-3); and a vertical extraction system, ultraviolet
(UV)/oxidation treatment, and discharge alternative (GW-4).
9.1.1 Alternative GW-l: Minimal No Action
The minimal no-action alternative provides a baseline against which other
alternatives can be compared. This alternative does not involve remedial actions to
treat contaminated groundwater. The contaminant plume would not be removed
from the aquifer. The minimal no-action alternative would include sampling
of existing monitoring wells, and some of the observation wells proposed to be
installed for the alternatives involving extraction. Review of the site would also be
conducted every five years. The minimal no-action alternative would not reduce risk
and would not meet the response objectives described in Subsection 8.1.
Estimated Time for Design. and Construction: 6 Months
Estimated Time of Operation: 5 Years
Installation Restoration Program
WOO3929.080
9-1
-------
SECI'lON 9
Estimated Capital Cost: None
Estimated Operations and Maintenance Costs (net present worth).: $236,000
to $506,000
Estimated Total Cost (net present worth).: $236,000 to $506,000
.Net present worth oosts are based on a 10 percent discount factor and five years of
operation.
9.1.2 Alternative GW-2: Extraction, Carbon Adsorption Treatment, and Discharge
The extraction, carbon adsorption treatment, and discharge alternative consists of the
environmental monitoring program described for the minimal no-action alternative
and a groundwater containment and treatment system. The components of this
alternative are as follows:
.
.
groundwater extraction wells
activated carbon treatment
discharge of treated water
environmental. monitoring well sampling
hydraulic performance monitoring
.
.
.
To facilitate containment of contaminated groundwater, an extraction well system
would be installed. . The volume of AOC CS-4 groundwater is estimated to be
approximately 790 million gallons, assuming an aquifer porosity of 30 percent. The
area of containment is shown in Figure 6-3. Using data from the AOC CS-4
pumping test, it is estimated that 13 extraction wells. yielding approximately 115 gpm
total could be installed at the toe of the plume to contain AOC CS-4 groundwater.
In addition, observation wells would be installed to evaluate the effectiveness of the
extraction system. The exact number and location of wells would be determined
during remedial design.
After extraction, carbon adsorption would remove the VOCs found in AOC CS-4
groundwater. . Activated carbon, a highly porous substance, selectively adsorbs
contaminants by a surface attraction phenomenon in which organic molecules are
attracted to the internal pores of the carbon granules. Once the micropore surfaces
Installation Restoration Program
WOO3929.080
9-2
-------
SEcTIoN.'
are saturated with .organics, the carbon is considered spent and must be replaced with
virgin carbon, or removed, thermally regenerated, and replaced. Contaminants are
permanently destroyed during the regeneration process. The time for the carbon to
be considered spent will be assessed by monitoring influent and effluent chemical
concentrations.
Treated. groundwater would be pumped from the treatment plant to infiltration
trenches located cross gradient from the plume, where the water would be allowed
to infiltrate below grade and return to the aquifer from which it was removed. The
infiltration area would be prepared with sand, gravel, and other materials. Water
would be distributed by perforated pipes over the trench area.
Chemical sampling of existing monitoring wells and some of the proposed
observation wells would monitor the plume's flowpath and chemical concentrations.
Sampling proposed monitoring wells upgradient of the infiltration area will assess
groundwater contaminant levels upgradient of the discharge area. The proposed
monitoring program is described in the AOC CS4 groundwater FFS and outlined in
Section 5.0 of this ROD (ABB Environmental Services! Inc., 1992a). As an interim
remedy, this alternative would provide an increased level of protection to
downgradient receptors, compared to baseline conditions. The extraction and
treatment system would contain the AOC CS-4 groundwater plume and treat this
water to the appropriate discharge requirements (Le., MCL concentrations). This
alternative is expected to provide a permanent reduction in contaminant
concentrations in groundwater. .
Estimated Time for Design and Construction: 1 Year
Estimated. Time of Operation: 5 Years
Estimated Capital Cost: $1,641,000 to $3,516,000
Estimated Operations and Maintenance Costs (net present worth):* $472,000
to $1,012,000
Estimated Total Cost (net present worth):* $2,113,000 to $4,528,000 .
Installation Restoration Program
WOO3929.080
9-3
-------
SECTION 9
*Net present worth costs are based on a 10 percent discount factor and five years of
operation.
9.1.3 Alternative GW-3: Extraction, Air-stripping Treatment, and Discharge
The extraction, air-stripping treatment, and discharge alternative would be similar to
the GW-2 alternative, except that VOCS would be removed by air stripping, followed
by vapor-phase carbon adsorption. Extraction of groundwater, discharge of treated
groundwatet:, environmental. and hydraulic monitoring, and a five-year review would
.be identical to the GW-2 alternative. .
Air stripping removes relatively volatile components from groundwater by passing air
through the contaminated water. To accomplish this, groundwater is pumped to the
top of an air-stripping tower and allowed to flow down through packing materials to
the bottom; At the same time, air is blown upward through the tower and packing
materials. Volatile contaminants transfer from water to air. The air is then treated
using activated carbon in a manner similar to the preferred alternative. The vapor-
phase carbon would be reactivated off-site so that it could be used again at a later
date.
As an interim remedy, this alternative would provide an increased level of protection
to downgradient receptors, compared to baseline conditions. The extraction and
treatment system would contain the Aoe eS-4 groundwater plume and treat this
water to the appropriate discharge requirements (i.e., MCL concentrations). This
alternative is expected to provide a permanent reduction in contaminant
concentrations in groundwater.
Estimated Time for Design and Construction: 1 Year
Estimated Time of Operation: 5 Years
Estimated Capital Cost: $1,832,000 to $3,925,000
Estimated Operations and Maintenance Costs (net present worth)*: $698,000
. to $1,496,000
Estimated Total Cost (net present worth) *: $2,530,000 to $5,421,000
Installation Restoration Program
WOO3929.080
9-4
-------
. 5ECI'lON 9
-Net present worth costs are based on a 10 percent discount factor and five years of
operation.
9.1.4 Alternative GW-4:
Discharge
Extraction, Ultraviolet/Oxidation Treatment, and
The extraction, UV /oxidation treatment, and discharge alternative would be similar
to the GW-2 alternative, except that VOCs would be removed by UV /oxidation
treatment in place of carbon adsorption. Extraction of groundwater, discharge of
. treated groundwater, environmental and hydraulic monitoring, and a five-year review
would be identical to the GW-2 alternative.. .
In place of the carbon adsorption unit described in the GW-2 alternative, a
UV / oxidation reactor would be used. The UV / oxidation technology destroys organic
compounds in wastewater and groundwater through chemical oxidation enhanced by
exposure to the UV light. UV / oxidation occurs in a stainless steel chamber
containing vertically or horizontally mounted UV lamps. An oxidant is added to the
water in the tank, which breaks down contaminants into less harmful chemicals. The
UV light enhances the oxidant's ability to break down. contaminants. The oxidant
proposed for this alternative is hydrogen peroxide.
As an interim remedy, this alternative would provide an increased level of protection
to downgradient receptors, compared to baseline conditions. The extraction and
treatment system would contain the AOe eS-4 groundwater plume and treat this
water to the appropriate discharge requirementS (i.e., MCL concentrations). This
alternative is expected to provide a permanent reduction in contaminant
concentrations in groundwater.
Estimated Time for Design and Construction: 1 Year
Estimated Time of Operation: 5 Years
Estimated Capital Cost: $2,443,000 to $5,234,000
Estimated Operations and Maintenance Costs (net present worth).: $584,000
to $1,251,000
Installation Restoration Program
WOO3929.080
9-5
-------
SECI10N 9
Estimated Total Cost (net present worth) *: 53,027,000 to 56,485,000
.Net present worth costs are based on a 10 percent discount factor and five years of
. operation. .
9.2 SOURCE CONTROL ALTERNATIVES ANALYZED
No source control alternatives were evaluated as part of this ROD. AOC CS-4 soils
are being addressed separately as part of a removal action for three sites (ABB
Environmental Services, InC., 1991). This separation of the source area soils and the
downgradient groundwater is consistent with the operable unit approach outlined in
the NCP. H implemented in conjunction with the source control remediation, these
groundwater alternatives would provide a sitewide response plan for AOC CS-4.
Installation Restoration Program
WOO3929.080
9-6
-------
SEcrION 10
10.0 SUMMARY OF THE COMPARATIVE ANALYSIS OF .ALTERNATIVES
'Section 121(b)(l) of CERCLA presents several factors that, at a minimum, NGB is
required to consider in its assessment of alternatives. Building on these specific
statutory mandates, the NCP articulates nine evaluation criteria to be used in
assessing the individual remedial alternatives." .
A detailed analysis was performed on the alternatives using the nine evaluation
criteria to select an interim site remedy. The following summary compares each
alternative's strength and weakness with respect to the nine evciIuation criteria.
These criteria and their definitions are discussed in the following subsections.
10.1 THRESHOLD CRITERIA
The following two threshold criteria described must be met for alternatives to be
eligible for selection in accordance with the NCP:
.
Overall Protection of Human Health and the Environment addresses
whether 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.
.
Compliance with ARARS addresses whether a remedy will meet all of
the ARARs of other federal and state environmental laws and/or
provide grounds for invoking a waiver.
10.2 PRIMARY BALANCING CRITERIA
The following five criteria are used to compare and evaluate the alternatives that
meet the threshold criteria:
Installation Restoration Program
WOO3929.0S0
10-1
-------
SECI'ION 10
.
Long-term Effectiveness and Permanence assesses alternatives for the
long-term effectiveness and permanence they afford, along with the
degree of cenainty that they will prove successful.
.
Reduction of Mobility, Toxicity, or Volume Through Treatment
addresses the degree to which alternatives employ recycling or
treatment that reduces mobility, toxicity, or volume, including how
treatment is used to address the principal threats posed by the site.
.
Short-term Effectiveness addresses the time needed to achieve
protection and any adverse impacts on human health and the
environment.
.
Implementability addresses the technical and administrative feasibility
of a remedy, including the availability of materials and services needed
to implement a panicular option.
.
Cost addresses the estimated capital and operations and maintenance
costs on a present-worth basis.
10.3 MODIFYING CRITERIA .
The modifying criteria are used on the final evaluation of remedial alternatives
generally after NGB has received public comment on the FFS and Proposed Plan:
.
.
State Acceptance addresses the Commonwealth's position and key
concerns related to the preferred alternative and other alternatives
including comments on ARARs or the proposed use of waivers.
Community Acceptance addresses the public's general response to the
alternatives described in the FFS and Proposed Plan reports.
Following the detailed analysis of each alternative, a comparative analysis, focusing
on the relative performance of each alternative against the nine criteria, was
conducted. The comparative analysis is presented in the FFS (ABB Environmental
Services, Inc., 1992a).
WOO3929.080
Installation Restoration Program
10-2
-------
SECI10N 10
The following subsection presents the nine criteria and a brief narrative summary of
the alternatives and their strengths and weaknesses according to the detailed and
comparative analysis.
10.4 OVERALL PROTECI10N OF HUMAN HEALTH AND THE ENVIRONMENT
All the remedial alternatives, except the minimal no-action alternative, would provide
an increased level of protection to human receptors. The minimal no-action
alternative was not designed to achieve remedial action objectives. Alternatives
GW-2, GW-3, and GW4 include containment, treatment, and discharge components
that would effectively reduce contaminant concentrations in groundwater. Protection
is provided by containment of the plume to prevent the migration of contaminated
groundwater to currently uncontaminated areas.
10.5 COMPLIANCE WITH ARARS
The minimal no-action alternative was not designed to achieve remedial action
objectives and, therefore, would not comply with chemical-specific ARARs.
Groundwater treatment, carbon adsorption, or W / oxidation is expected to remove
VOCs.
The design of the AOC eS4 groundwater containment option would be based on
compliance with location- and action-specific ARARs. The final treatment standards
for groundwater would be based on achieving discharge requirements. In addition,
all work conducted at AOe CS4 would be in accordance with Occupational Safety
and Health Administration (OSHA) requirements.
10.6 LONG-TERM EFFECl'lVENESS AND PERMANENCE
The minimal no-action alternative would not meet remedial action objectives. Aoe
eS-4 groundwater would continue to pose a risk to human health until natural
attenuation reduced contaminant levels in the groundwater. Environmental
monitoring and site reviews would evaluate the effectiveness of natural attenuation
Installation Restoration Program
WOO3929.080
10-3
-------
SECTION 10
in reducing contaminant concentrations; future remedial actions may be
recommended.
The other three groundwater treatment ahematives (Le., Alternatives GW-2, GW-3,
and GW-4) would meet remedial action objectives for groundwater because the water
would be collected and treated before it could migrate farther downgradient. Each
treatment option is considered to provide a permanent remedy for removal of
contaminants in AOe CS-4 groundwater. Future long-term remedial actions will be
evaluated once Aoe eS-lO groundwater has been sufficiently. characterized.
10.7 REDucnON OF MOBILI'IY, TOXICI'IY, OR VOLU~
This criterion is relevant only for treatment alternatives. The minimal no-action
alternative does not reduce the mobility, toxicity, or volume of contaminants or
contaminated media. All three of the water treatment alternatives would reduce the
mobility, toxicity, and volume of contaminants in groundwater. The reductions for
each treatment alternative are evaluated in the FFS (ABB Environmental Services,
Inc., 1992a).
10.8 SHORT-TERM EFFECI'lVENESS
Implementing the minimal no-action alternative would not result in additional
adverse impacts on human health or the environment than already exist from AOe
eS-4 groundwater. For the other alternatives, impacts on human health would result
from increased drilling equipment and construction materials transponed to the site.
Impacts on the environment during remedial activities include the removal of trees
during site preparation before installing the extraction system, treatment units, and
discharge area. However, these components would be designed to have minimal
impact on the environment.
Impacts to workers implementing remedial actions as part of Alternative GW-2,
GW-3, and GW-4 would be mitigated by the use of appropriate personal protective
equipment and clothing and by following safe work practices, as outlined in a Health
and Safety Plan. These impacts would be minimal to workers implementing the
Installation Restoration Program
WOO3929.0SO
10-4
-------
SECTION 10
environmental monitoring programs as part of Alternative GW-l because no invasive
work would be required.
10.9 IMPLEMENTABlLfIY
All the remedial alternatives are implementable, although obtaining access to the
Crane Wildlife Refuge Area to conduct monitoring or remedial actions would require
coordination with personnel responsible for MMR security. Each technology
described is well developed and widely available, and has . been successfully
demonstrated at other Superfund sites. If it is determined that additional remedial
actions are necessary in the future, the AOC C5-4 groundwater treatment system may
require modification or replacement. .
10.10 COST
The alternative cost estimates are a combination of costs estimated for each
component. Each remedial alternative includes the cost of the institutional controls
and environmental monitoring program given for Alternative GW-l, minimal no
action.
The least expensive alternative is the minimal no-action alternative, estimated to cost
up to $506,000. For Alternative GW-2, GW-3, and GW-4, the costs of the three
different types of treatment processes were compared. The total costs of the three
groundwater containment and treatment alternatives are similar and are discussed
in Section 9.0 of this ROD.
10.11 STATE ACCEPTANCE
The Commonwealth of Massachusetts has indicated its concurrence with the selected
remedy; this concurrence letter is presented in Appendix B.
Installation Restoration Program
WOO3929.080
10-5
7030-04
-------
SECI'ION 10
10.U COMMVNm' ACCEPTANCE
Based on the written and oral comments received during the recent comment period,
there is general acceptance of the selected remedy, although some people
commenting requested more information. Responses to community comments are
in Appendix E.
iiiSiiffidion Restoration Program
WOO3929.080
10-6
-------
SECI'lON 11
11.0 THE SELECTED INTERIM REMEDY
The NGB has chosen Alternative GW-2 as the selected alternative. Alternative
GW-2 is .an interim remedy, the goals of which are to manage the migration of
contaminants, treat the contaminated groundwater to reach the discharge limits, and
discharge treated groundwater crossgradient from the groundwater plume, while the
AOC CS-10 plume is characterized and final remedial alternatives are studied.
11.1 CLEAN-UP LEVELS
Clean-up levels have been established for the contaminants of concern identified in
the risk assessment that are found to pose an unacceptable risk to either human
health or the environment. Oean-up levels have been set based on the appropriate
ARARs (e.g., drinking waterMCLs and MCLGs, if available). In the absence of a
chemical-specific ARM, or other suitable criteria to be considered, a 10-5 excess
cancer risk level for carcinogenic effects or a concentration corresponding to an HI
of 1.0 for compounds with noncarcinogenic effects was used to set clean-up levels.
In instances in which the values described were not feasible to quantify, the Practical
Quantitation Limit was used as the clean-up level. Periodic assessments of the
protection afforded by the remedial action will be made as the interim remedy is
implemented. If the interim remedial action is not found to be protective, further
action will be required while the final remedy is developed.
Because the aquifer at the compliance boundary of AOC CS-4 is a Class I aquifer,
MCLs and non-zero MCLGs established under the Safe Drinking Water Act
(SDWA) are ARMs.
Clean-up levels for known and probable carcinogenic compounds have been set at
the appropriate MCL. In the absence of an MCL, a proposed drinking water
standard, or other suitable criteria (i.e., health advisory or state standard), a clean-up
level was- derived for carcinogenic effects based on a 10-5 excess cancer risk level for
groundwater ingestion.
Table 11-1 summarizes the clean-up levels for the VOCs of concern identified in
. groundwater. The clean-up lev~ls must be met at the completion of the final
Installation Restoration Program
WOO3929.080
11-1
-------
TABLE 11-1
. PROPOSED TREATMENT lEvELs
AOC C5-4 GROUNDWATER RECORD OF DECISION
MASSACHUSETTS MIUTARY RESERVATION
LEva OF RISK
.. ........
. .CARCINOGEN CONTAMItWn'S. ... . TREATMENT
OF CoNcERN .. L2VEL BASIS INGESTION INHALATION
Tetrachloroethylene 5 pg/L MCL 3x10-6 1X10-6
Trichloroethylene . 5 pg/L MCL 7x10.7 . 3X10.7
1,1,2,2-Tetrachloroethane 2 pg/L * 1X10.s 9X10-6
SUM 2X10.5 1X10.5
HAzARD INDEX
NON-CARCINOGEN
CoNTAMINANTS TREATMENT
OF CoNCERN .. LEvEL BAsIS .INGESTION INHALATION
1,2-Dichloroethylene 70 pg/L MCL 1X10.' -
Tetrachloroethylene 5 pg/L MCL 1X10.2 -
Trichloroethylene 5 pg/L MCL - -
1,1,2,2-Tetrachloroethane 2 pg/L * - -
SUM 1x10.' -
No..:
.
The 1,1.2.2-tetrachloroethane detected in groundwater does not have Federal MCLa, MCLGs, or Massachusetts MCLa, MCLGs; therefore, a
risk-baud treatment level was propoud. The risk-buect treatment level was calculated assuming a 1x10' risk level and using the USEPA
risk guidance for human.health exposure scenarios.
Per USEPA Region I direction residual risks were calculated on the following assumptions:
ingestion rate: 2 liters/day
average body weight: 70 kg
frequencY 01 exposure: 365 days/year
duration of exposure: 70 years
life expectancy: 70 years
These assumptions differ from the assumptions on USEPA 1991 OSWER Directive 9285.6-00 and those uud in the baseline risk
assessment.
JI9/L
MCL
MCLG
USEPA
micrograms per liter
Maximum Contaminant Level
Maximum Contaminant Level Goal
U.S. Environmental Protection Agency
WOO3929.T80/9
-------
L
SECI'lON 11
remedial action. The interim remedial action will operate for a minimum of five
. years. The NGB has estimated that the clean-up level will be attained within 30
years. The clean-up levels are consistent with ARARs for groundwater and attain
USEPA's risk management goal for remedial actions.
11.2 DESCRlmON OF REMEDIAL COMPONENTS
The selected interim remedy, Alternative GW-2, to remediate contaminated
. groundwater consistS of groundwater eXtraction wells at the leading edge of the AOC
CS-4 plume; treatment of the collected groundwater; and discharge of the treated
groundwater onto MMR property. Figures 11-1 and 11-2 show the approximate
locations of the groundwater extraction wells, piping to the treatment plant, and
approximate locations of the treatment plant and treated groundwater infiltration
trenches. The selected alternative is expected to operate for a minimum of five
years, during which time monitoring and characterization of the CS-10 groundwater
plume will be performed. A [mal remedy will be determined to address the CS-10
and CS-4 groundwater plumes. .
Groundwater extraction would be accomplished using a netWork of approximately 13
vertical extraction wells positioned across the width of the plume and the depth of
contamination. The extraction wells would be equidistant from one a..'1other, located
60 feet apart, and pumped to provide a combined flow rate of 115 gpm. Observation
wells downgradient and to the sides of the extraction wells would be installed to
evaluate hydraulic effectiveness of the extraction .system.
Pumping extraction wells is effective in containing plumes in groundwater because
pumping draws down the local groundwater.table, inducing gradients that cause the
groundwater to flow toward the well instead of the normal flow direction.
Positioning the extraction wells at the toe of the plume would prevent the plume
from moving farther downgradient. Extraction wells are simple to install. Wells and
pumps can be sized to handle a wide range of flow rates. Locating well screens
within the plume would increase the effectiveness of capture. Potential drawbacks
of this technology are installation of the wells in the Crane Wildlife Refuge Area and
potential for influencing the flowpath of the AOe CS-lO groundwater plume, which
has not been fully characterized to date. .
Installation Restoration Program
WOO3929.080
11-3
-------
AUAIIIIIOwH_1II
r
o
7030.02
J
4.000
MTALLAT10N AfSTDAATK* "'DO".".
MASSAOtUSETTS _'TA",. It£SE"YATIQtI
2.000
1 1-4
PREFERRED
ALTERNATIVE LAYOUT
Aoe
eS-4
ROD
-------
ID
N
~
~
o
I
'J'!
-
.,
GROUND SURFACE
,.
WATER TABLE
,/
-
jl 1.1.
r......
ASEA BROWN lOVER!
ABB Environmental
Services Inc.
GROUNDWATER EXTRACTION AND
CARBON TREATMENT SYSTEM
AOC
CS-4
ROD
INSTALLATION RESTORATION PROGRAM
MASSACHUSETIS MIUTARY RESERVATION
-------
SECTION 11
The effect of AOC CS-4 extraction on the AOC CS-lO groundwater plume cannot
be evaluated until the aquifer is actually pumped; therefore, this interim remedial
action would need to be carefully monitored during implementation. Coordination
would be required among officials at MMR, the Crane Wildlife Refuge Area,
construction contractors, and environmental monitoring personnel to ensure that
access can be obtained for both long- and short-term activities associated with the
interim remedy. .
If iron and manganese were in the groundwater at high enough concenttations, they
would interfere with the organic groundwater treatment system (carbon adsorption).
Groundwater samples were collected in December 1991 from two monitoring wells.
One well was located near the expected location of the extraction wells; the other in
the middle of the plume. The samples had low iron and manganese concentrations;
therefore, removal of iron and manganese. would not be required.
An on-site activated carbon adsorption treatment system would effectively remove
organic materials from water by sorption (Le., the attraction and accumulation of one
substance on the surface of another). As water passes through porous granules of
carbons, contaminant molecules are attracted to the surface of the pores and held
there by weak physical forces.
As activated carbon adsorbs molecules from water, the carbon pores become
saturated witb contaminants. An activated carbon adsorption system would require
units to be connected in series. Figure 11-3 is a schematic of a typical carbon
adsorption system. Regular sampling of effluent from the first carbon bed in the
series would be required to assess the breakthrough point. Breakthrough occurs
when the concentration of the target pollutant in the effluent is higher than the
desired level. Once the carbon has been spent, . a new charge of carbon would
replace the spent carbon. Spent carbon would be reactivated off-site to be used
again on-site at a later date. Minimal carbon waste is generated.
Carbon treatment units are readily available and would be implementable for AOC
CS-4 groundwater. If the contact time in the carbon units is sufficient, this process
will remove up to 99 percent of the absorbable organics in Aoe eS-4 groundwater.
. .
Treated groundwater would be pumped from the treatment plant to infiltration
trenches located cross gradient from the plume, where the water would be allowed
Installation Restoration Program
WOO3929.0BO
11-6
-------
TWO-VESSEL GRANULAR CARBON ADSORPTION SYSTEM
FROM EXTRACTION SYSTEM
REGENERAIE~AKfUP
Al: IIVA lED CARBON
BACKWASH EFFLUENT
BACKWASH FEED
......
I
-....J
SOURCE: USEPA, 1985.
7001-05
ADIOR8fR I
REGENERA'E~AKEUP
AC IIVA UOCAflBON
BACKWASH EfFLUENT
ADSORBER I
BACKWASH FEED
SPtNI CARBON
DISCHARGE Of
TREATED EFFLUENT
H VALVE CLOSED
[X] VALVE OPEN
j~ 1.1. ABB Envlrcnn8n1a1
.,..... Service., Inc.
AII.-- .
INSTALLATION RESTORATION PROGRAM
MASSACHUSETTS MIlITARY RESERVATION
TWO.YESSEL GRAtU..AR
CARBON ADSORPTION SYSTEM
AOC
CS.4
ROD
-------
SECl'ION 11
to infiltrate below grade and return to the aquifer from which it was removed. The
infilttation ttenches would be prepared with perforated pipe, sand, gravel, and other
materials. Water would be distributed by perforated pipes over the trench area.
The discharge area would be located to (1) not adversely influence the flowpath of
other plumes along the southern boundary of MMR (Le., the FTA-l and Ashumet
Valley plumes); (2) be in an area where no other plumes have been identified to
date; and (3) be on MMR property. The proposed location of the crossgradient
discharge is approximately 2,000 feet west of the Otis Wastewater Treatment Plant
and 600 feet north of the MMR boundary. The area is shown in Figure 11-1.
The objective of the monitoring program would be to, evaluate the effectiveness of
the groundwater extraction wells to contain the groundwater contaminant plume, to
deteniline the reduction in contaminant concentrations as the treatment progresses,
and to determine groundwater quality upgradient of the discharge area. The
environmental monitoring plan would involve' sampling of groundwater. Samples
would be analyzed for Target Compound List VOCS; some wells would be sampled
for other compounds. Existing wells and some of the observation wells were
proposed for sampling to provide infonnation on contaminant movement attenuation
and dispersion in groundwater. Monitoring wells are proposed to be installed
upgradient of the infilttation area to monitor upgradient groundwater quality. These
wells would provide information on levels of contaminants entering the extraction
area and monitor groundwater quality and plume migration.
To the extent required t>y law, the NGB and USEP A will review the AOe CS-4 site
at least once every five years after initiation of the remedial action until no
hazardous substances, pollutants, or contaminants remain on the site. The review
will ensure that the remedial action continues to protect human health and the
environment. The NGB and USEPA will also evaluate the risk posed by AOe eS-4
at the completion of the final remedial action.
Installation Restoration Program
WOO3929.080
11-8
-------
SECTION U
U.o STATUTORY DETERMINATIONS
The interim remedial action selected for implementation at AOC CS-4 is consistent
with CERClA and, to the extent practicable, the NCP. The selected interim remedy
protects buman bealtb and tbe environment, attains .ARARs, and is cost-effective.
The selected remedy, which is not designed or expected to be final, also satiSfies the
statutory preference for treatment tbat permanently and significantly reduces the
mobility, toxicity, or volume of hazardous substances. Additionally, tbe selected.
remedy uses alternate treatment technologies or resource recovery technologies to
the maximum extent practicable..
U.l
THE SELECl'ED INTERIM REMEDY 15 PROTECTIVE OF HUMAN HEALTH AND
THE ENVIRONMENT
The remedy at AOC CS-4 will permanently reduce the risks posed to human health
by eliminating, reducing, or controlling exposures to human and environmental
receptors through treatment, engineering controls, and institutional controls. More
specifically, this remedy will provide an increased level of protection to downgradient
receptors by containing the AOC CS-4 groundwater plume and treating the
contaminated water to the appropriate discharge requirements. Moreover, the
selected remedy will result in human exposure levels that are within the 10-4 to 10-6
incremental cancer risk range and that are within the HI of 1.0 for noncarcinogens.
This remedy will result in treated discharge less. than the MCLs.
Environmental risks do not currently exist from contaminants in the groundwater
from AOC CS-4. Environmental risks would only be possible if tbe contaminated
groundwater were allowed to migrate farther south and discharge into Coonamessett
Pond. Because groundwater will be remediated before it reaches the pond, there
would be no effect by AOC CS-4 groundwater on that surface water body.
Finally, implementing tbe selected interim remedy will not pose unacceptable short-
term risks or. cross-media impacts. Remedial construction activities are not likely to
adversely affect the public or MMR personnel. Initial grading of the treatment
system location and installation of groundwater monitoring and observation wells are
not expected to encounter or expose contaminants. The greatest potential threat to
Installation Restoration Program
WOO3929.080
12-1
-------
SECl10N 12
the public from construction-related activities would be due to fugitive dust created
during site preparation. Ambient air monitoring for respirable dust would be
conducied during remedial construction activities. Engineering controls for dust
suppression are readily available and could be implemented easily if necessary.
12.2
THE SELECl'ED INTERIM REMEDY A1TAlNS ARARs
This remedy will attain all applicable or relevant and appropriate federal and state
requirements that apply to this limited scope interim action for AOC CS-4
groundwater. Generally, MARs for the selected interim remedial action are a
subset of those listed in Tables 4-1 through 4-3 of the FFS. The ARARs that do
correspond to this interim action are listed in Tables U-1 through 12-3. A narrative
summary of significant ARARs is provided in the following subsections. .
12.2.1 Location-specific ARARs
Location-specific ARARs for AOC CS-4 groundwater are identified in Table 12-1.
Sole-source Aquifer Regulations. In general, projects that would be subject to review
under the sole-source aquifer program include highway or building construction
projects, either. of which could have potentially detrimental effects on human health
and the surrounding environment. The proposed CERCLA. activities would not
increase current contaminant concentrations in the sole-source aquifer; the proposed.
interim remedial action would actually decrease the contaminant concentrations of
AOC CS-4 groundwater and of the aquifer.
12.2.2 Chemical-specific ARARs
Chemical-specific ARARs are identified in Table 12-2 and are briefly discussed in
the following paragraphs.
Groundwater Regulations. The SDW A drinking water standards were used, when
available; to develop Target Clean-up Levels for AOC CS-4 groundwater.
Massachusetts also has groundwater quality standards that limit the concentrations
of certain material. allowed in groundwater. The federal standards were relevant and
Installation Restoration Program
WOO3929.0SO
12-2
-------
TABLE 12-1
LOCATlON-SPECFIC ARARs. CRITERIA. ADVISORIES. AND GOOANCE
AOC CS-4 GROUNDWATER RECORD OF DECISION
MA88ACHUSElT8 MOAb RE88IVATION
MmlA
CONIIJEM 110N II THE IIfTBI8I ROD
SOLE-SOURCE AQUIFERS
REQUIREMENT
STATUS
REQUIREMENT SYNOP8I8
The classffication of the groundwater beneath Cape
Cod as a sole-source aquifer was given c~n8lderatlon
In the risk assessment, and therefore In the
development of target cleanup levels for AOC CS-4
groundwater.
Note. :
Federal
SDWA Sole-Source
Aquifers (40 CFR 149)
Relevant and
Appropriate
USEPA Is authorized to designate aquifers as sole
source and review federal financially assisted projects
In the arel to determine the project's potential to
contaminate the aquifer. No federal a88lstance may
be made for projects that may contaminate the
aquifer. Conversely, federal funds may be used to
modify projects to ensure they will not Contaminate
the aquifer.
ARAR
CERCLA =
CFR
t:) USEPA
~ SDWA
ROD
,/
Applicable or Relevant and Appropriate Requirements
Comprehensive Environmental Response, Compensation, and Uability Act
Code of Federal Regulations
U.S. Environmental Protection Agency
Safe Drinking Water Act
Record of Decision
-------
TAIU 12-2
CHEMICAL-SPECIFIC ARARa, CIITEIIA, ADVI8ORIEa, AM) GUIDANCE
AOC CS-4 GROUNDWATBI RECORD OF DECISION
MA8MCHU8ETTa MIJTARY RE8S!VAT/ON
MEDIA
REQUIREMENT
STATUI
GROUNDWATERI
SURFACE WATER
Coi8DEM noN IN tHE INTSI.. ROD
Federal
.-
N
j..
Federal Guidance and
Criteria To Be
Considered
~
WOO3929.T80/14
SDWA - MCLs (40 CFR
141.11 - 141.16)
SDWA - MClGs (40 CFR
141.50 - 141.51)
RCM - Subpart F
Groundwaler Protecllon
Standards, Alternate
Concentration Umlts
(40 CFR 264.94)
USEPA RIDs
USEPA Carcinogen
Assessment Group CPFs
Massachusel1s Drinking
Waler Siandards
(310 CMR 22.00)
Massachusel1s Groundwater
Ouallty Standards
(314 CMR 6.06)
Relevan1 and
Appropriate
Relevant and
Appropriate
Relevant and
Appropriate
To Be Considered
To Be Considered
Relevant and
Appropriate
Applicable
REQUIREMENT IYNOP8I8
MCLs heve been promulgated for I8V8ral common
organic and Inorganic contamInants. Thel8 levels
regulate the concentration of contaminants In public
drinking water Supplies, but may also be considered
relevant and appropriate for groundwater aquifers used
lor drInking water.
MClGs are heahh-based criteria. As promulgated under
SARA,. MClG. are to be considered for drInking waler
SOurces. MClGs are available for several organIc and
Inorganic contaminants.
This requirement outlines standards, In addition to
background concentrations and MCls, to be used In
establishing cfean-up levels for remediatlng groundwater
contamination.
RIDs are considered the levels unlikely 10 cause
"gnlf/cant adverse health effecta aSSOCIated with a
threshold mechanism of action In human exposure for a
IIletime.
Carcinogenic effects present the most up-to-date
Information on cancer risk potency derived from USEPA'.
Carcinogen Assessment Group.
Massachusel1s Drinking Water Standards with the
exception of sodium are equivalent to federal MCls.
When state levels are more strIngent than federallevel.,
the state level. may be used.
These standard. limit the concentration of certain
malerlals allowed In classified Massachusel1s waters.
The groundwater beneath MMR has been classified as a
aass I water or fresh groundwater found In Ihe satoJrated
zone of unconsolidated deposits and Is designated as a
source 0' polable waler supply.
To aSI888 the potential rIsk. to human health due to
consumption of groundwater, contamInant
concentratIons were compared to their MCls. When
available, the MCls were used to set clean-up levels
for AOC CS-4 groundwater contamInants.
The 1990 National Contingency Plan stales that non-
zero MClGs are to be used as goals. Contaminant
concentrations In groundwater were compared to their
MCLGs when I8l1/ng clean-up levels.
These requirements may be relevant and approprIate
If certaIn conditions relating to Iransport and exposure
are met. Because MCls were available for mosl
compounds, alternate concentration limits were nol set.
USEPA RIDs ware used to characterIze risks due to
noncarcfnogens In varIous media.
USEPA CPFs were used to compute the Individual
Incremental cancer risk resulting from exposure to
certain compounds. .
DrinkIng water standards, when available, were used to
set clean-up levels.
These standards will be al1alned because the crean-up
levels or potential discharge limits were set u$.lng these
-------
continued
TAILE 12-2
CHEMICAL-SPECIFIC ARARI. CRITERIA. ADVISORIES. AND GUIDANCE
AOC CS-4 GROUNDWATER RECORD OF DECISION
MASSACHUSETT8 MIJTAJIY REsalVATION
MEDIA
CON8l)ERA noN . TiE 'NTE1181 ROD
REQUIREMENT
STATUS
REQUIREMENT SYIIIOP8I8
State
Massachuse"s HWMR-
Maximum Concentration of
Constituents for
Groundwater Protection
(310 CMR 30.668)
State Guidance and
Criteria to Be
Considered
.....
N
I
~
Massachuse"s Drinking
Water Guidelines
Relevant and
Appropriate
This requirement established three categories of'
groundwater protection ltandards: background,
concentratlonl, maximum concentratlonl, and alternate
concentrations. The maximum concentratlonl .,e
Identical to federal SDWA MCLs.
Complying with federal MCls as target clean-up levels
will be consistent with state standards. .
In the absence of drinking water standards, the88.
guidelines would have been considered when 88"lng
target clean-up levels or discharge limits. However,
MCLs or rlsk-ba.sed target clean-up levels were set, for
AOC CS-4 groundwater; the88 guidelines were not
necessary to develop cleanup levels.
Note.:
ARM
CERCLA =
CFR .
CMR
CPF
HWMR
MCl
MClG
MMR
OSWER =
RCRA
AtD
SARA
SDWA
USEPA
ROD
To Be Considered
The Office of Research arid Standards uses. a
methodology similar to the USEPA OffIce of Drinking
Water when se"lng guidelines. Carcinogens have
guidelines set at the lowest practical quantltatlon limit or.
a level which would pose an excess cancer risk of 10',
For noncarclnogens, a percentage (usually 20 percent) Is
applied to published or derived route-specific, reference
doses and standard exposule assumption to derive a
drinking water concentration.
Applicable or Relevant and Appropriate Requirement
Comprehensive Environmental Response, Compensation, and Uabillty Act
Code of Federal Regulations
Code of MassachuseUs Regulations
carcinogenic potency factor
Hazardous Waste Management Rules
Maximum Contaminant level
Maximum Contaminant level Goal
Massachuse"s Military Reservation
Office of Solid Waste and Emergency Response
Resource Conservation and Recovery Act
reference dose
Superfund Amendments and Reauthorization Act
Safe Drinking Water Act
U.S. Environmental Protection Agency
Record of Decision
-------
TAllE 12-3 .
ACnON-SPECIFIC APPUCAlLE OR RB.EVANT AND APPIIOPIIATE REOUIIEMENT8
Aoe eS-4 GROUNDWATER RECORD OF DECISION
MASSACHUSETT8 ManARY RESERVATION
REQUIREMENT STATUI REOUIIEIIENT SyNOP8l8 CON8lOEllAT1ON II THE IrnBuM ROD
. Federal
OSHA - General Industry Standards Applicable These re~ulatlons specify the &;hour Proper respiratory equipment will be worn If It Is
(29 CFR Part 1910) tlme-W8~ ted avera~e concentration Imr:SSlble to maintain the work atmosphere
for va ous organ c compounds. be ow the concentration. Workers performing
Training requirements for workers at remedial activities would be re~ulred to have
hazardous wastes operations are completed specific training requ rements. .
specified In 29 CFR 1910.120.
OSHA - Safety and Health Standards Applicable This regulation specifies the type of All :ccroprlate safe~ equipment will be
(29 CFR Part 1926) safety equipment and procedures to be avalla e on site. In ad lIIon, safety procedures
followed during site remediation. will be followed during on-site remedial
activities.
OSHA - Recordke~lng, Reporting, and Related Applicable This regulation outlines the These. requirements apply to all site contractors
Regulations (29 C R 19(4) ,ecordkeeplng and reporting and aubcontractors, and must be followed
r~ulrernents foi an employer under during all site work.
OHA.
- RCRA - Standards Applicable to Generators of Applicable this requirement sets standards for " any alternative proposes shipping wastes off
t-.J
, Hazardous Waste (40 CFR Part 262) generators of hazardous waste that . site. the material must be shipped In proper
0\ address (1) accumulating waste, containers that are accurateey marked and
(2) preparing hazardous waste for labeled. and the transporter must display
shipment, and (3) preparing the proper placards. All waste shipments would
uniform hazardous waste manifest. accompanied by an appropriate manifest.
These requirements are Integrated with
DOT regulations.
DOT Rules for Transportation of Hazardous Materials Applicable this regulation outlines procedures for Hazardous and contaminated materials will be
(49 CFR Parts 107, 171.1-172.558) the packeglng, labeAnsi. manifesting, caaged, manifested, and transported to a
and transporting of hazardous censed off-site disposal facility In compliance
materials. with these regulations. .
Clean Air Act - National Primary and Secondary Applicable Primary ambient air quality standards The standard for partlculat, matter of less than
Ambient Air Quality Standards (40 CFR 50) define levels of air quality to protect 10 microns Is 150 #191m, 24-hour averae:
human health. concentration. These standards would
adhered to for Invasive construction activities.
Applicable Secondary ambient air quality These standards would be complied with for
standards protect CubliC welfare from remedial construction activities.
known or antlclpa ed adverse' effects
from pollutants.
-------
continued
TABLE 12.3 .
ACnON-SPECIFIC APPlICABLE OR RElEVANT AND APPIIOfIItIATE REQUllEMENT8
AOC CS-4 GROUNDWATER RECORD OF DECI8ION
MASSACHUSETTS MUTARY REsERVATION
REQUIREMENT STATUS REQUIREMENT SVNOP8I8 CON8IDERATION . THE INTERIM ROD
State
Massachusetts HWMR - location Standards for Relevant and Under these standards, a new facility The treatment facility will be located and
Facilities Appropriate ma~ not be located In an area subject operated to fulfill these regulations.
(310 CMR 30.700 - 30.707) to oodlng; within the watershed of a ..:~
Class A or Class SA segment of the
surface water body unless It is
determined that there Is no feasible.
alternative; on land overlying an actual,
planned, or potential public or private
drinking water source; or In the flow
path of .r.roundwater surlclyin~ water to
an exls n~ well. In add on, ere shall
be a mln mum of 300 feet from the
active portion of the facility to the
..... facility property line.
tV
I Massachusetts HWMR - Requirements for Generators Relevant' and These requirements are similar to the When a waste or residual waste Is moved, the
-..J
(310 CMR 30.300 - 30.371) Appropriate federal RCRA regulations for generator requirements would be complied
generators. Massachusetts specifies. with.
requirements for very small quantity
generators, as well as small and large
quantity generator..
Massachusetts HWMR - Requirements for Relevant and These regulations are similar to the Hazardous materials will be transported ~ a
1rans8orters. Appropriate federal RCRA transportation licensed operator to an o"-8Ite disposal fa lity
(310 MR 30.400 - 3O.4t6) requirements. In addition, lIabll:y. as specified In these requirements.
Insurance must be obtained by I
licensed hazardous waste transporters
and each vehicle must have a vehicle
Identification device.
Massachusetts Groundwater Discharge Permits Relevant and Permit information, InCludlns Discharge of treated water to the ground or
(314 CMR 5.00) Appropriate conditions and variances, are speclfle groundwater would comply with the substantive
In these regulations. requirements of these regulations.
Massachusetts Air Pollution Control Regulations Relevant and These regulations outline the standards Particulate standard Is 75 JIQ/rf!l' annual
(310 CMR 6.00 - 8.00) Appropriate for air pollution control, Including geometric mean and 150 pg m 24-hour
particulate matter, carbon monoxide, avera~e concentration. These standards would
nitrogen dioxide, and lead. be ad ered to during construction activities.
-------
....
t-..)
I
00
continued
REQUIREMENT
TAlLE 12-3
ACTION-SPECFIC APPlICAlLE OR RB.EVANT AND A"""OPIIIATE REQtRMENT8
AOC CS-4 GROUNDWATER RECORD OF DECIllION
MASSACHUSETT8 MIJTAIIY RnalvA110N
STATUI
REQUllEMENT SVNOP8l8
Relevant and
Appropriate
The regulations establish rules and
re~ulrements for the dissemInation of
Information related to toxic and
hazardous lubstances to the public.
These regulations establish
requIrements for wortcer rlght-to-know.
informatIon applicable to site activities and
characterIstIcs will be made available to on-site
workers.
C0N8IDEM11ON ... THE INTER8I ROD
Implementation of M.G.L. Chapter 111F, Employee
and Community Rlght-to-Know (310 CMR 33.00,
~
Worker Rlght-to-Know (441 CMR 21.(0)
information applicable to site activities and
characteristics win be made available to the
public.
Relevant and
Appropriate
Not.e:
ARARs
CM
CERCLA '"
CFR
CMR
CWA
DOT
HWMR
LORs
MGL
MMR
NESHAP '"
NPDES
OSHA
POTW
RCRA
SDW1
(1jg'
ROD
w003929. T80/3
=
Applicable or Relevant and Appropriate Requirements
Clean Air Act
Comprehensive Environmental Response, Compensation, and Uabillty Act
Code of Federal Regulations
Code of Massachusetts Regulations
Clean Water Act
Department of TransportatIon (U.S.)
Hazardous Waste Management Rules
Land Disposal Restrictions
Massachusetts General Law .
Massachusetts Military Reservation .
National EmissIon Standards for Hazardous Air Pollutanta
National Pollutant Discharge 81mlnatlon System
Occupational Safety and Health AdmInistration
publicly owned treatment works
Resource Conservation and Recovery Act
Safe Drinking Water Act
micrograms per cubic meter
volatile organic compound
-------
SECI'ION 12
appropriate and the state standards were applicable as chemical-specific requirements
. in determining effluent discharge limits, although the discharge will be occurring
from an on-site treatment facility to the groundwater. The criteria would be met by
setting effluent discharge limits, designing and constructing a treatment process to
meet those levels, and by monitoring the process for compliance with the criteria.
The other requirements listed in Table 12-2 were used in the risk assessment and
development of Target Clean-up Levels for those compounds that did not have
promulgated drinking water standards.
12.2.3 Action-specific ARARs
Action-specific ARARs for the selected remedy are presented in Table 12-3. A
summary of requirements that must be attained are discussed in the following brief
descriptions.
't
Air Regulations. Federal and state air quality standards exist for particulate matter
and would be used in assessing excavation and construction emission controls. These
standards are relevant and appropriate, rather than applicable, because they were
originally developed to control stack and automobile emissions. Threshold Limit
Values established by OSHA regulations provide an extensive list of control levels
applicable to on-site remediation activities such as installation of the extraction wells
and collection network, and the treatment system. Air-related ARARs would be met
through the use of engineering controls and monitoring during construction of the
remedy. . . .
Water Regulations. Substantive requirements of the Massachusetts Groundwater
Discharge Permits would be relevant and appropriate to the on-site discharge of
treated groundwater. The effluent from the treatment process would be monitored
to evaluate compliance with these regulations.
Hazardous Waste Regulations. The off-site shipment of hazardous materials would
. be subject to U.S. Department of Transportation rules. H the spent carbon or other
residuals are determined to be hazardous wastes, the treatment facility would have
to comply with the substantive Resource Conservation and Recovery Act
requirements for generators and transporters.
Installation Restoration Program
WOO3929.080
12-9
-------
SEcrION 12
Other Action-specific Regulations. Federal OSHA requirements that regulate worker
and employee records should be followed during all on-site work. These regulations .
include safety and health standards for federal service contracts and recordkeeping,
reporting, and related regulations. Because these regulations govern general working
conditions within industry and provide minimum protection standards for workers
involved in remedial actions, these regulations are applicable.
Massachusetts has hazardous s:ubstance right-to-know regulations that establish
requirements to protect the health and safety of employees and community residents
through the communication of information regarding toxic and hazardous substances.
These regulations are relevant and appropriate to on-site workers during the interim
remedial action. .
12.3 THE SELECI'ED INTERIM REMEDIAL ACTION 15 COST..EFFECTIVE
In the NGB's judgment, the selected remedy affords overall effectiveness
proportional to its costs. Once the NGB identified alternatives that are protective
of human health and tbe environment and that attain ARARs, the NGB evaluated
tbe overall effectiveness of each alternative by assessing the three relevant criteria:
reduction in mobility, toxicity, and volume through treatment
short-term effectiveness
long-term effectiveness and permanence
The relationship of the overall effectiveness of this remedial alternative was
determined to be proportional to its costs. The costs of this interim remedial
alternative are as follows:
.
.
.
Estimated Capital Cost: $1,641,000 to $3,516,000
Estimated Operations and Maintenance Cost (net present worth) *: $472,000 to
$1,012,000
Estimated Total Cost (net present worth)*: $2,112,000 to $4,528,000
Installation Restoration Program
WOO3929.080
12-10
-------
SEcrION 12
.Net present wonh costs are based on a 10 percent discount factor and five years of
operation. .
12.4
THE SELECl'ED INTERIM REMEDY UTILIZES PERMANENT SOLUTIONS AND
AL1ERNA11VE TREATMENT OR REsOURCE RECOVERY TECHNOLOGIES TO THE
MAxIMUM EXTENT PRACTICABLE
The NGB identified which alternative uses permanent solutions and alternative
treatment technologies or resource recovery technologies. to the maximum extent
practicable. This determination was made by identifying an alternative that provides
the best balance of trade-offs in terms of the following criteria:
.
long-term effectiveness and permanence
reduction of mobility, toxicity, or volume through treatment
short-term effectiveness
implementability
cost
.
.
.
.
The balancing test emphasized long-term effectiveness, permanence, and the
reduction of mobility, toxicity, and volume through treatment This interim test also
considered the preference for treatment as a principal element, the bias against off-
site land disposal of untreated waste, and community and state acceptance. The
selected remedy provides the best balance of trade-offs among the alternatives, given
the limited scope of. the interim action selecied. Consideration of long-term
effectiveness does not apply due to the short-term nature of the selected remedy.
The selected remedy will achieve reduction of mobility, toxicity, or volume through
treatment of extracted groundwater, thereby reducing migration of contaminants.
The selected interim remedy would have no implementation difficulties. Carbon
adsorption technology is well demonstrated and the equipment is readily available.
The selected remedy will achieve the goals of the interim action; that is, reduction.
of contaminant migration and collection of further data to characterize the AGC
CS-lO groundwater plume for use in selecting the final remedy, while costing the
least of the active interim options.
Installation Restoration Program
WOO3929.080
12-11
-------
SECI'lON 12
12.5
THE SELECTED INTERIM REMEDY SATISFIES THE PREFERENCE FOR
TREATMENT WHICH PERMANENTLY AND SIGNIFICANTLY REDUCES THE
MOBILm, Toxlcm, OR VOLUME OF THE HAzARDous SUBSTANCES AS A
PRINCIPAL ELEMENT
, .
The principal element of the selected remedy is the extraction and treatment of
groundwater at the leading edge of the AOC CS4 contaminated groundwater plume
and its subsequent discharge to on-site infiltration trenches. This element addresses
the primary exposure pathway at the site for this operable unit: contamination of
groundwater. The selected remedy satisfies the statutory preference for reduction
in the mobility, toxicity, or volume to the extent possible in light of its limited scope
by extracting and treating contaminated groundwater and preventing its further
migration to downgradient areas. This interim ROD will be followed by a final ROD
that will determine what further actions, if any, will be necessary to meet the
preference for treatment that will permanently and significantly reduce the mobility,
toxicity, or volume of hazardous substances.
Installation Restoration Program'
WOO3929.080
12-12
-------
SECTION 13
13.0 DOCUMENTATION OF NO SIGNIFICANT CHANGES
The NGB presented a Proposed Plan for remediation of AOe eS-4 in
February 1992. The management of migration portion of the preferred alternative
included extraction of contaminated groundwater, treatment of the collected
groundwater, and discharge of the treated groundwater to an infiltration basin on
MMR property. There have been no significant changes made to the plan as stated
in the Proposed Plan of February 1992 (ABB Environmental Services, Inc., 1992b).
. " .
Installation Restoration Program
WOO3929.080
13-1
-------
SECflON 14
14.0 STATE ROLE
MADEP, on behalf of the Commonwealth of Massachusetts, reviewed the various
alternatives and indicated its support for the selected interim remedy. MADEP also
reviewed the FFS to determine if the selected remedy is in compliance with
applicable or relevant and appropriate state environmental regulations. .MADEP
concurs with the selected remedy for AOC CS-4 groundwater. A copy of the
declaration of concurrence is in Appendix B. . .
Installation Restoration Program
WOO3929.080
14-1
-------
REFERENCES
ABB Environmental Services, Inc., 1991. "Study Areas CS-4, FS-25, and FTA-1
Engineering Evaluation/Cost Analysis Report"; Installation, Restoration
Program; Massachusetts Military Reservation; prepared for HAZWRAP;
Portland, Maine; June 1991.
ABB Environmental Services, Inc., 1992a. "Groundwater Focused Feasibility Study,
West Truck Road Motor Pool (AOC CS-4)"; Installation Restoration
Program; Massachusetts Military Reservation; prepared for HAZWRAP;
Portland, Maine; February 1992.
ABB Environmental Services, Inc., 1992b. "Groundwater Proposed Plan, West Truck
Road Motor Pool (AOC CS-4 )"; Installation Restoration Program;
Massachusetts Military Reservation; prepared for HAZWRAP; Portland,
Maine; February 1992. .
Army Environmental Hygiene Agency (AEHA), 1986. "U.S. Army Environmental
Hygiene Agency Geohydraulic Study No. 38-26-0500-86; Camp Edwards,
Massachusetts; July 8-10 and September 9-17, 1985"; April 1986.
E.C. Jordan Co., 1986. "Task 6, Phase I Records Search: Air National Guard, Camp
Edwards, U.S. Air Force, and Veterans Administration Facilities at
Massachusetts Military Reservation"; prepared for Oak Ridge National
Laboratory; Oak Ridge, Tennessee; December 11, 1986.
E.C. Jordan Co., 1989a. . "Site Inspection Report, Field Investigation Work
Conducted Fall 1987, Task 2-3A"; Installation Restoration Program;
Massachusetts Military Reservation; prepared for HAZWRAP; Portland,
. Maine; March 1989. '
E.C. Jordan' Co., 1989b. "Hydrogeologic Summary Report, Task 1-8"; Installation
Restoration Program; Massachusetts Military Reservation; prepared for
HAZWRAP; Portland, Maine; April 1989.
E.C. Jordan Co., 1990a. "Site Inspection Report, Field Investigation Work
Conducted Spring-Summer 1988, Task 2-3B"; Installation Restoration
Program; Massachusetts Military Reservation; prepared for HAZWRAP;
Portland, Maine; February 1990.
Installation Restoration Program
WOO3929.080
70~
-------
REFERENCES
E.e. Jordan Co., 1990b. 'Technical Memorandum, Phase n Investigations of the
MW-603 Groundwater Study"; Installation Restoration Program;
Massachusetts Military Reservation; prepared for HAZWRAP; Portland,
Maine; February 1990. ..
E.C. Jordan Co., 1990c. ''Technical Report, Phase I of the MW-603 Groundwater
Study (Study Area CS-4, West Truck Motor Pool, Groundwater Operable.
Unit)"; Installation Restoration Program; Massachusetts Military Reservation;
prepared for HAZWRAP; Portland, Maine; March 1990. .
E.C. Jordan Co., 1990d. "Focused Feasibility Study, West Truck Road Motor Pool
Site: Study Area CS-4, Source Control Operable Unit"; Installation
Restoration Program; Massachusetts Military Reservation; prepared for
HAZWRAP; Portland, Maine; June 1990.
U.S. Environmental Protection Agency (USEPA), 1986. "Hazardous Waste
Management System; Identification and Listing of Hazardous Waste; Final
Exclusion and Final Organic Leachate Model (OLM)"; Code of Federal
Regulations, Title 40, Part 261; Final Rule; Federal Register; Vol. 51, No. 219;
November 13, 1986.
U.S. Environmental Protection Agency (USEPA), 1989. "Determining Soil Response
Action Levels Based on Potential.Contanrinant Migration to Ground Water:
A Compendium of Examples"; USEPA 540/2-89/057.
U.S. Environmental Protection Agency (USEPA), 1990. "National Oil and
Hazardous Substances Pollution Contingency Plan (National Contingency
Plan)"; Code of Federal Regulations, Title 40, Part 300; March 8, 1990; Final
Rule; Federal Register; Vol. 55, No. 46; pp. 8666 et seq.
Installation Restoration Program
WOO3929.080
-------
.
GLOSSARY OF ACRONYMS AND ABBREVIATIONS
AEHA
ANG
AOC
°ARAR
Army Environmental Hygiene Agency
Air National Guard
Area of Contamination
Applicable or Relevant and Appropriate Requirement
CERClA
Comprehensive Environmental Response, Compensation, and
Liability Act °
Clean° Water Act
CWA
DCE
DOD
DPDO
dichloroethylene
Department of Defense (U.S.)
Defense Property Disposal Office
. engineering evaluation/cost analysis
° EE/CA
FFS
ft/yr
focused feasibility study
feet per year
gpm
gallons per minute
HI
Hazard Index
IRP
Installa~ion Restoration Program
MADEP
MCL
° MCLG
MMR
Massachusetts Department of Environmental Protection
Maximum Contaminant Level
Maximum Contaminant Level Goal
Massachusetts Military Reservation
NCP
NGB
NPL
National Contingency Plan
National Guard Bureau
National Priorities List
OLM
OSHA
Organic Leachate Model
Occupational Safety and Health Administration
PCE
tetrachloroethylene
Installation Restoration Program
WOO3929.080
-------
GLOSSARY OF ACRONYMS AND ABBREVIATIONS
RID
ROD
reference dose
Record of Decision
SDWA
Safe Drinking Water Act
TCE
TEAC
Ilg/kg
Ilg/L
USAF
USEPA
UST
UV
trichloroethylene . .
Technical Environmental Affairs Committee
micrograms per kilogram
micrograms per liter
U.S. Air Force
U.S. Environmental Protection Agency
underground storage ~
ultraviolet
VOC
volatile organic compound
Installation Restoration Program
WOO3929.0BO
7030-04
-------
APPENDIX B
STATE CONCURRENCE LE1TER
4'
Installation Restoration Program
WOO3929.080
-------
~
~.,
--
Corrmonweolth of Massachusetts
Executive OttICe of Environmental MOIlS
Departm.nt .f .
Enylronmental Protectioll
-
-
-
-
D E P
--P. Weld
0MINr
DIdI8I" OFM,Mv..
~-" -
... Julie aelap
Raq10nal Adm1n1atrator
u.s. BPA R8qion 1
JF1C Pederal Buildinq
lSoston, Massachusetts 02103
and
U:
aOCRHB--BWSC SA4-0037
Ma..achu.8~~. K111~ary
Re8ervation (laIR) Az- ot
Conta.ination Ch..ical
Spill-4 (CS-4) Groundwatar
Interim Record of Dec~
Concurrence -
Hr. Ronald Watson
Chief, Environmental
»lCRC/CD
National Guard Bureau
Buildinq 3500
Andrews APB, .aryland
Division
May 18, 1992
20331-6008
Dear Ms. Belaqa and Mr. Watson:
The Department of Environmental protec1:ion CDD) hall reviewed
t.h. preferred remedial action alternative recommended by the
National Guard Bureau and the U. s. BPA for an interim cleanup of
the CS-4 groundwater contaminant plume at the MMR National
priorities List Site.
The DEP has evaluated the preferred alternative tor
consistency with M.G.L. Chapter 21E and the Ma..achu.etts
continqency Plan. The propos.d a1 ternati V8 i. a qrounc1water
containment action that addre.... the continued downqradient
miqration of contaminated qroundwatar oriCiJinatinq a~ C5-4. Th.
interim remedY' consists ot approxim4tely 13 extraction wells.
positioned across the width and depth of the plWD8. The extraction
wella will b. .quidis~an~ from one ano~her, loca~ed60 f..~ ap~,
and will pWDp a com!:>ined flow rate of 115 gpm- The extracted
qroundwatar will be treated with granular activated carbon to
remove volatile orqanic compounds and clean water will be
di8charqed throuqh infiltration tr.nch...
The interim remedY will be operated tor a minimum of five
years, dur1nq which time the CS-10 qrounclwater contaminant plume,
known to be located upqrad1ent trom the CS-4 plume, will tie tUlly
characterized and options for remediation evaluated. A final remedy
will be determined to address the CS-4 and CS-10 groundwater
plumes. .
OM WlntIIr 81Net
. Bolton, UaMlOhuMttl 02108
.
-------
1-
-2-
'!'h. DEP has c!etarmin.c! 1:.hat the interim rem8C!y i. a r_dia1
action on a portion of the disposal 8i te which would be consi.tent
with a future permanent .olution tor the entire disposal .ite.
Bowever, a permanent solution determination cannot be maele until it
has b.en demonstrateel that the remedial response action or
combination of action. will meet the 'rotal site Ri.k Limite a.
defined in the Massachusetts continqenoy Plan (MCP) 310 CMR 40.00
for the .ite.
The DEI' has identified 1:11. MCP and H.G.I.. Chapter 211 a.
applicable rec:ruir_ants, within the meaning ot CERCLA, tor the CS-o&
Groundwater Operable Unit of the MMR National Prioritie. List Site.
'!'he ..lec1:8c! remedy appears to _et all ......chuaett. .tate
Applicable or Relevant an4 Appropriate Raquir..enta (ARARa). The
DBP will continue to evaluate compliance with ARAR8 a. remedial
design progre..e. and durin; impl..entation and oparation.
. '1'he DEP looks forward to working with you in !mpl..entinq the
preterred alternative anel facilitatinq an exp8C!itioua cleanup of
the MKR .ite. If you have any c:rue8tioft8 ple..e contact Jame. F.
Begley at (508) 90&6-2871. .
,
1 . Greenbaum, commissioner
Department of Environmental Protection
cc: SWSC Soston .
TEAC Distribution
------- |