Superfund Record of Decision Fort Devens Areas of Contamination 43G and 43J Fort Devens MA


                                    EPA/ROD/R01-97/158
                                    1997
EPA Superfund
     Record of Decision:
     FORT DEVENS
     EPA ID: MA7210025154
     OU06
     FORT DEVENS, MA
     10/17/1996

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EPA/541/R-97/158

                                  RECORD OF DECISION
                           AREAS OF CONTAMINATION 43G AND 43J
                                 DEVENS, MASSACHUSETTS

                                     OCTOBER 1996

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                                  RECORD OF DECISION
                            AREAS OF CONTAMINATION 43G AND 43J
                                  DEVENS, MASSACHUSETTS

                                  TABIiE OF CONTENTS

Section                                  Title                                         Page No.

DECLARATION FOR THE RECORD OF DECISION 	 i

DECISION SUMMARY 	 1

I.     SITE NAME, LOCATION, AND DESCRIPTION 	 1

II.    SITE HISTORY AND ENFORCEMENT ACTIVITIES 	 1
      A.   Land Use and Response History 	 1
      B.   Enforcement History 	 2

III.   COMMUNITY PARTICIPATION 	 3

IV.    SCOPE AND ROLE OF THE RESPONSE ACTION 	 5

V.     SUMMARY OF SITE CHARACTERISTICS 	 6
      A.   AOC 43G 	 6
      B.   AOC 43J 	 7
           1.     Soils 	 8
                 a.    AOC 43G 	 8
                 b.    AOC 43J 	 8
           2.     Groundwater 	 9
                 a.    AOC 43G 	 9
                 b.    AOC 43J 	 10

VI.    SUMMARY OF SITE RISKS 	 11
      A.   AOC 43G 	 11
           1.     Subsurface Soil 	 11
           2.     Groundwater 	 12
      B.   AOC 43J 	 13
           1.     Subsurface Soil 	 14
           2.     Groundwater 	 14

VII.   DEVELOPMENT AND SCREENING OF ALTERNATIVES  	 16
      A.   Statutory Requirements/Response Objectives 	 16
      B.   Technology and Alternative Development and Screening  	 17
           1.     AOC 43G  	 17
           2 .     AOC 43 J  	 18

VIII.  DESCRIPTION OF ALTERNATIVES 	 18
      A.   AOC 43G 	 18
           1.     Alternative 1: No Action 	 18
           2.     Alternative 2A: Intrinsic Bioremediation 	 19
           3.     Alternative 2B: Intrinsic Bioremediation/Soil Venting of
                 Gasoline UST Soils 	 20
           4.     Alternative 3: Groundwater Collection and
                 Treatment/Intrinsic Bioremediation 	 21
           5.     Alternative 4: Intrinsic Bioremediation/Hydraulic
                 Containment 	 22
           6.     Alternative 5: Groundwater Collection and Treatment/Soil
                 Treatment 	 23

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TABLE OF CONTENTS
(continued)
Section Title Page No.

B. AOC 43J 24
1. Alternative 1: No-Action 24
2. Alternative 2: Intrinsic Bioremediation 24
3. Alternative 3: Intrinsic Bioremediation/Passive In-situ
Bioremedial Containment 25
4. Alternative 4: Intrinsic Bioremediation/Hydraulic
Containment 26

IX. SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES 27
A. AOC 43G 29
1. Overall Protection of Human Health and the Environment 29
2. Compliance with Applicable or Relevant and Appropriate
Requirements 31
2. Long-term Effectiveness and Permanence 32
4. Reduction of Toxicity, Mobility, and Volume through
Treatment 32
5. Short-term Effectiveness 33
6. Implementability 33
7. Cost 34
8. State Acceptance 35
9. Community Acceptance 35
B. AOC 43J 35
1. Overall Protection of Human Health and the Environment 35
2. Compliance with Applicable or Relevant and Appropriate
Requirements 36
3. Long-term Effectiveness and Permanence 37
4. Reduction of Toxicity, Mobility, and Volume through
Treatment 38
5. Short-term Effectiveness 39
6. Implementability 39
7. Cost 40
8. State Acceptance 41
9. Community Acceptance 41

X. THE SELECTED REMEDY 42
A. Groundwater Cleanup Levels 42
1. AOC 43G 42
2 . AOC 43 J 43
B. Description of Remedial Components 45
1. AOC 43G 49
2. AOC 43J 49

XI. STATUTORY DETERMINATIONS 52
A. The Selected Remedy is Protective of Human Health and the
Environment 53
B. The Selected Remedy Attains ARARs 53
C. The Selected Remedy is Cost-Effective 54
D. The Selected Remedy Utilizes Permanent Solutions and Alternative
Treatment or Resource Recovery Technologies to the Maximum
Extent Practicable 55
a. AOC 43G 55
b. AOC 43J 57

XII. DOCUMENTATION OF NO SIGNIFICANT CHANGES 59
XIII. STATE ROLE 59

APPENDICES
APPENDIX A - FIGURES
APPENDIX B - TABLES
APPENDIX C - RESPONSIVENESS SUMMARY
APPENDIX D - ADMINISTRATIVE RECORD INDEX
APPENDIX E - DECLARATION OF STATE CONCURRENCE
APPENDIX F - GLOSSARY OF ACRONYMS AND ABBREVIATIONS

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                           DECLARATION FOR THE RECORD OF DECISION

SITE NAME AND LOCATION

Areas of Contamination  (AOC) 43G and 43J
DEVENS, Massachusetts

STATEMENT OF PURPOSE AND BASIS

This decision document presents the U.S. Army's  (Army) selected remedial action for AOC 43G and 43J at
Devens, Massachusetts. It was developed in accordance with the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) of 1980 as amended, 42 USC °° 9601 et seq. and the National Oil
and Hazardous Substances Pollution Contingency Plan (NCP) as amended, 40 CFR Part 300, to the extent
practicable. The Devens Base Realignment and Closure  (BRAG) Environmental Coordinator; the Installation
Commander; and the Director of the Waste Management Division, U.S. Environmental Protection Agency
(USEPA) New England have been delegated the authority to approve this Record of Decision.

This Record of Decision is based on the Administrative Record that has been developed in accordance with
Section 113(k) of CERCLA. The Administrative Record is available for public review at the Devens BRAG
Environmental Office, Building P-12, Devens, Massachusetts, and at the Ayer Town Hall, Main Street, Ayer,
Massachusetts. The Administrative Record Index (Appendix D of this Record of Decision) identifies each of
the items considered during selection of the remedial action.

ASSESSMENT OF THE SITE

Actual or potential releases of hazardous substances from AOCs 43G and 43J, if not addressed by
implementing the response action selected in this Record of Decision, may present an imminent and
substantial endangerment to the public health, welfare, or the environment.

DESCRIPTION OF THE SELECTED REMEDY

This remedial action addresses long-term commercial/industrial exposure to contaminated groundwater, the
principal known threat at both AOC 43G and 43J. The selected remedial alternative for both AOC 43G and
43J relies on intrinsic bioremediation, groundwater and contaminant modeling, and long-term groundwater
monitoring to evaluate the effectiveness of the alternative at controlling groundwater contamination and
site risk. The remedy will mitigate existing groundwater contamination through natural attenuation and
bioremediation and reduce the potential risk of future commercial/industrial exposure to contaminated
groundwater. The major components of the selected remedy for both AOC 43G and 43J include:

       •      intrinsic bioremediation

       •      intrinsic bioremediation assessment data collection and groundwater modeling

       •      installing additional groundwater monitoring wells

       •      long-term groundwater monitoring

       •      annual data reports  to USEPA and Massachusetts Department of Environmental Protection
              (MADEP)

       •      five-year site reviews

If the intrinsic bioremediation assessment results at AOC 43G and 43J indicate that: 1) the groundwater
contaminant plume may increase in size on Army property and/or, 2) the groundwater contaminant plume
remains the same size, but cannot be remediated within 30 years; a soil vapor extraction  (SVE) system win
be installed at the existing AOC 43G source area, and an additional cleanup action will be implemented at
AOC 43J. Furthermore, if at any time during this remedy there is an indication that contaminants are
migrating off Army property or an area located sufficiently inside the boundary in which compliance will
be determined, according to cleanup criteria stated in the Record of Decision, that at minimum will meet
drinking water standards; then the Army will implement an additional remedial action which will be
protective of human health and the environment.

Should the Army change the use of either AOC, additional assessment and/or possible remedial action, may
be needed based upon the possibly resultant changed risk factors. In addition, if the Army transfers
either AOC by lease or deed, an Environmental Baseline Survey  (BBS) will be conducted, and a
determination will be made by the Army and USEPA that the selected remedy remains protective of human

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health and the environment.

STATE CONCURRENCE

The Commonwealth of Massachusetts has concurred with the selected remedy. Appendix E of this Record of
Decision contains a copy of the declaration of concurrence.

DECLARATION

The selected remedy is consistent with CERCLA, and to the extent practicable, the NCP, is protective of
human health and the environment, complies with federal and Commonwealth requirements that are legally
applicable or relevant and appropriate to the remedial action, and is cost effective. The remedy utilizes
permanent solutions and alternative treatment technologies, to the maximum extent practicable for both
AOC 43G and 43J.

The additional remedy at AOC 43G and/or 43J, if implemented, would also be consistent with CERCLA, and to
the extent practicable, the NCP, be protective of human health and the environment, comply with federal
and Commonwealth requirements that are legally applicable or relevant and appropriate to the remedial
action, and be cost effective. The remedy utilizes permanent solutions and alternative treatment
technologies, to the maximum extent practicable.

Because the selected remedy, for both AOC 43G and 43J, will result in hazardous substances remaining
on-site above health-based levels, a review will be conducted within five years after commencement of the
remedial action to ensure that the remedy, at each AOC, continues to provide adequate protection of human
health and the environment.

The foregoing represents the selection of a remedial action by the U.S. Department of the Army and the
U.S. Environmental Protection Agency, with the concurrence of the Commonwealth of Massachusetts
Department of Environmental Protection.
Concur and recommend for immediate implementation:

Concur and recommend for immediate implementation:

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DECISION SUMMARY

I. SITE NAME, LOCATION, AND DESCRIPTION

Fort Devens, is a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) National
Priorities List (NPL) site located in the Towns of Ayer and Shirley,(Middlesex County) and Harvard and
Lancaster (Worcester County), approximately 35 miles northwest of Boston, Massachusetts. Prior to
closure, the installation occupied approximately 9, 600 acres and was divided into the North Post, Main
Post, and South Post (Figure 1 in Appendix A).

This Record of Decision addresses subsurface soil and groundwater contamination at Area of Contamination
(AOC) 43G, and groundwater contamination at AOC 43J. Both AOCs are located within the newly created
Devens Reserve Forces Training Area. AOC 43G is located on Queenstown Road in the central portion of the
Main Post Reserve Forces Training Area. AOC 43J is located on Patton Road at the southern edge of the
Main Post Reserve Forces Training Area (see Figure 1 in Appendix A).

II. SITE HISTORY AND ENFORCEMENT ACTIVITIES

A. Land Use and Response History

Fort Devens, was established in 1917 as Camp Devens, a temporary training camp for soldiers from the New
England area. In 1931, the camp became a permanent installation and was redesignated as Fort Devens.
Throughout its history, Fort Devens served as a training and induction center for military personnel, and
as a unit mobilization and demobilization site. All or portions of this function occurred during World
Wars I and II, the Korean and Vietnam conflicts, and Operations Desert Shield and Desert Storm. During
World War II, more than 614,000 inductees were processed and Fort Devens reached a peak population of
65,000.

The primary mission of Fort Devens was to command, train, and provide logistical support for
non-divisional troop units and to support and execute Base Realignment and Closure (BRAG) activities. The
installation presently supports the Army Readiness Region and National Guard units in the New England
area.

Fort Devens was selected for cessation of operations and closure under the Defense BRAG Act of 1990
(Public Law 101-510). The installation was officially closed in 1996 and was renamed Devens,
Massachusetts.

A more complete description of AOC 43G and 43J can be found in the individual Remedial Investigation (RI)
reports, February 1996, Section 5, and the Feasibility Study (FS) report, June 1996, Subsection 1.2.

B. Enforcement History

In conjunction with the Army's Installation Restoration Program (IRP), Fort Devens and the U.S. Army
Environmental Center (USAEC; formerly the U.S. Army Toxic and Hazardous Materials Agency [USATHAMA])
initiated a Master Environmental Plan (MEP)in 1988. The MEP assessed the environmental status of study
areas (Sas) , discussed necessary investigations, and recommended potential responses to environmental
contamination. Priorities for environmental restoration at Fort Devens were also assigned. The MEP
identified 18 historic gas station sites (SA 43B through 43S) and the then active petroleum, oils, and
lubricant (POL) storage area (SA 43A) , as some of the potential sources of groundwater contamination and
recommended that each SA be investigated to determine the distribution of contamination.

On December 21, 1989, Fort Devens was placed on the NPL under CERCLA as amended by the Superfund
Amendments and Reauthorization Act (SARA) . A Federal Facilities Agreement (Interagency Agreement [IAG] )
was developed and signed by the Army and USEPA Region I on May 13, 1991, and finalized on November 15,
1991. The IAG provides the framework for the implementation of the CERCLA/SARA process at Fort Devens.

In 1991, the U.S. Department of Defense, through USAEC, initiated site investigations (Sis) at the
historic gas station Sis at Fort Devens. The SI Data Package was issued in January 1993 and the Final SI
report was issued in May 1993, summarizing the data collected during the SI phase at each of the historic
gas station SAs. A preliminary risk evaluation (PRE) , which compared concentrations of detected
contaminants to USEPA and MADEP risk-based standards, was also completed for each historic gas station in
the Final SI Report. Based on the collected data and the findings of the PRE, additional investigations
were recommended for a subset of the historic gas station (SA 43B, 43D, 43G, 43K 431, 43J, and 430). The
remaining SAs were recommended for no further action (NFA) or a removal action.
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In 1993, a supplemental SI (SSI) was conducted, at the above mentioned subset of Sas, to further define
the contamination detected during the SI. The SSI Data Package was issued in January 1994, and the
Revised Final SI report was issued in October 1995. Both documents presented the additional data
collected during the SSI, an updated PRE, and recommendations for additional activities. Based on the
findings of the SSI and the updated PRE, two sites (SA 43G and 43J) were transferred to the RI/FS phase,
and the remaining SAs were recommended for NFA or a removal action. The site designations for SA 43G and
43J were administratively changed to AOC, at this junction.

The purpose of the RI was to determine the nature and distribution of contamination at the AOCs, assess
the risk to human health, and provide a basis for conducting an FS. The RI at each AOC was completed in
1994 and the Final RI report for both AOCs was issued in February 1996.

FS reports that evaluated remedial action alternatives for cleanup of groundwater at AOC 43G and 43J were
issued in June 1996. The separate FS reports identified and screened four remedial alternatives at AOC
43G and five remedial alternatives at AOC 43J. Each FS also provided a detailed analysis of each of these
remedial alternatives to allow decision-makers to select a remedy for cleanup of groundwater at both
AOCs.

The proposed plan detailing the Army's preferred remedial alternative was issued in August 1996 for
public comment. Technical comments presented during the public comment period are included in the
Administrative Record. Appendix C, the Responsiveness Summary, contains a summary of these comments and
the Army's responses, and describes how these comments affected the remedy selection.

III. COMMUNITY PARTICIPATION

The Army has held regular and freguent informational meetings, issued a proposed plan and press releases,
and held a public meeting to keep the community and other interested parties informed of activities at
AOC 43G and 43J.

In February 1992, the Army released, following public review, a community relations plan that outlined a
program to address community concerns and keep citizens informed about and involved in remedial
activities at Devens. As part of this plan, the Army established a Technical Review Committee (TRC) in
early 1992. The TRC, as reguired by SARA Section 211 and Army Regulation 200-1, included representatives
from USEPA, USAEC, Devens, MADEP, local officials, and the community. Until January 1994, when it was
replaced by the Restoration Advisory Board (RAB), the committee generally met guarterly to review and
provide technical comments on schedules, work plans, work products, and proposed activities for the
SAs/AOCs at Devens. The SI, RI, and FS reports, proposed plan, and other related support documents were
all submitted to the TRC or RAB for their review and comment.

The Army, as part of its commitment to involve the affected communities, forms a RAB when an installation
closure involves transfer of property to the community. The Devens RAB was formed in February 1994. The
RAB consists of 28 members (15 original TRC members plus 13 new members) who are representatives from the
Army, USEPA Region I, MADEP, local governments and citizens of the local communities. It meets monthly
and provides advice to the installation and regulatory agencies on Devens cleanup programs. Specific
responsibilities include: addressing cleanup issues such as land use and cleanup goals; reviewing plans
and documents; identifying proposed reguirements and priorities; and conducting regular meetings that are
open to the public.

On August 25, 1996, the Army issued the proposed plan to citizens and organizations, to provide the
public with a brief explanation of the Army's preferred remedy for cleanup at both AOC 43G and 43J. The
proposed plan also described the opportunities for public participation and provided details on the
upcoming public comment period and public meetings.

A public notice announcing the public meeting was published the week of September 2, 1996 in the Times
Free Press/Public Spirit, the Lowell Sun, Fitchburg-Leominster Centennial and Enterprise, and the
Worcester Telegram. The Army also made the proposed plan available to the public at the information
repositories at the town libraries in Ayer, Shirley, Lancaster, and Harvard, and at the Devens BRAG
Environmental Office.

From August 25 to September 26, 1996, the Army held a 30-day public comment period to accept public
comments on the alternatives presented in the FS and the proposed plan and on other documents released to
the public. On September 5, 1996, the Army held a public meeting at Devens, to present the Army's
proposed plan to the public to accept verbal or written comments from the public, and discuss the cleanup
alternatives evaluated in the FS. This meeting also provided the opportunity for open discussion
concerning the proposed cleanup. A transcript of this meeting, public comments, and the Army's response
to comments are included in the attached Responsiveness Summary (Appendix C).
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All supporting documentation for the decision regarding AOC 43G and 43J is contained in the
Administrative Record for review. The Administrative Record is a collection of all the documents
considered by the Army in choosing the remedy for both AOC 43G and 43J. On August 26, 1996, the Army made
the Administrative Record available for public review at the Devens BRAG Environmental Office, and at the
Ayer Town Hall, Ayer, Massachusetts. An index to the Administrative Record is available at the USEPA
Records Center, 90 Canal Street, Boston, Massachusetts and is provided as Appendix D.

IV. SCOPE AND ROIiE OF THE RESPONSE ACTION

The Army developed the selected remedy by combining components of different source control and management
of migration alternatives. The selected remedy for AOC 43G and 43J will control the migration of
contaminants in groundwater, reduce contaminant concentrations, and control potential groundwater use.
The selected remedy will also provide environmental monitoring of groundwater for a period of up to
thirty years. The implementation of the selected alternative will not adversely affect any future
response actions at AOC 43G and 43J, should they be reguired.

This remedial action will address the principal threat to human health at AOC 43G and 43J posed by
long-term commercial/industrial worker exposure to contaminated groundwater.

V. SUMMARY OF SITE CHARACTERISTICS

A. AOC 43G

AOC 43G is located in the central portion of the Main Post on Queenstown Road (see Figure 1 in Appendix
A). The AOC consists of the former Army Air Force Exchange Service (AAFES) gas station and historic gas
station G (see Figure 2 in Appendix A).

Originally SA 43G consisted solely of historic gas station G, which was one of eighteen historic gas
station sites. The station was used during World War II as a vehicle motor pool to support military
operations. The motor pool operations were discontinued during the late 1940s or early 1950s. No records
were available on the decommissioning of the motor pool and therefore, there was no evidence of the exact
location of historic gas station G or that the station's underground storage tank (UST) had been removed.
The reported location of historic gas station G was southwest of the former AAFES gasoline station
(Building 2008) and southwest of Building 2009 (see Figure 2 in Appendix A). The structures of historic
gas station G consisted of a pump island and a small gasoline pumphouse. Reportedly, the gas station had
one 5,000-gallon (or possibly 5,140-gallon) UST located between the gasoline pumphouse and the pump
island.

AOC 43G was expanded to include the former AAFES gas station after the SI was completed in 1993. The
AAFES, gas station was added to further define the distribution of contamination detected during the past
gasoline UST removals (completed in 1990) , as well as the contaminants detected during a waste oil UST
removal completed in 1992. The waste oil UST removal was stopped prior to the removal of all contaminated
soil because of concerns that Building 2008 would be undermined. A completed description of the former
waste UST and gasoline UST removals are presented in the Final RI report.

The former AAFES gasoline station is located approximately 120 feet northeast of historic gas station G.
During the time of the field investigations, the AAFES gas station was comprised of the service station
(Building 2008) which houses three vehicle service bays and the former AAFES store, three 10,000-gallon
USTs, and associated pump islands. The AOC was divided into three areas during the SSI to better focus
the investigations. Area 1 was comprised of historic gas station G, Area 2 was made up of the former
10, 000-gallon gasoline USTs, and Area 3 was the former waste oil UST (see Figure 2 in Appendix A) .

The 10,000-gallon gasoline USTs, and associated piping, were removed by the U.S. Army Corps of Engineers
- New England Division in July/August 1996. In addition, the sand and gas trap and residual soil
contamination in Area 3 were removed during this removal action.

B. AOC 43J

AOC 43J is located on an access road in the central portion of the Main Post, that connects Patton Road
and Queenstown Road (see Figure 1 in Appendix A). The area around the location of AOC 43J, was most
recently used as a vehicle storage yard and maintenance facility (Building T-2446) for a Special Forces
unit of the U.S. Army. The former maintenance facility used a UST for storage of maintenance wastes. This
UST was located just south of Building T-2446. The yard and maintenance facility is paved with asphalt
and surrounded by a chain-link fence with a locked gate located at the northern side of the yard (Figure
3 in Appendix A).
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Prior to the building of the Special Forces unit vehicle maintenance facility, this area was historically
used as a gas station/motor pool (historic gas station J) during the 1940's and 1950's. The structures of
this historic gas station at AOC 43J consisted of a pump island and a small gasoline pumphouse. This gas
station was reported to be a Type A station which had one 5,000-gallon (or possibly 5,140-gallon) UST
located between the gasoline pumphouse and pump island. The station was used during World War II as a
vehicle motor pool to support military operations. The motor pool operations were discontinued during the
late 1940s or early 1950s. No records were available on the decommissioning of this motor pool or the
removal of the associated UST.

During the 1992 SI, an abandoned 5,000-gallon UST was detected at historic gas station J. This UST was
added to the Fort Devens; UST removal program and removed during the summer of 1992. At the same time the
former waste oil UST was also removed. During both UST removals, contaminated soil was removed and
disposed of by Fort Devens. A completed description of these removals is presented in the Final RI
report.

Section 1 of the AOC 43G and 43J FS reports, contains an overview of the RI completed at each AOC. A
complete discussion of site characteristics can be found in Sections 5, 6, and 7 of the RI reports,
February 1996. Significant findings of the RI are summarized in the following subsections.

1. Soils

a. AOC 43G

Analytes detected in soil samples collected during the SI, SSI, and RI at AOC 43G are consistent with the
historical use of this area as a gas station. The benzene, toluene, ethylbenzene, and xylene (BTEX) and
total petroleum hydrocarbon (TPHC) concentrations detected in Areas 2 and 3 indicate that residual soil
contamination is still present in these areas from leaks and spills associated with the former gasoline
and waste oil USTs. The results of the soil sampling in Area 2 show that residual fuel related soil
contamination appears to be present in the soil at the southeastern corner, and directly adjacent to the
former gasoline USTs, from approximately 20 to 28 feet below ground surface (bgs). The results of the
soil sampling at Area 3 indicate that residual soil contamination is present in the shallow soils
(approximately 6 to 8 feet bgs) below the former waste oil UST and around the former sand and gas trap
(see Figure 3 in Appendix A).

b. AOC 43J

Field analytical and off-site analytical laboratory data from TerraProbe SM and soil boring samples,
collected during the SI, SSI, and RI, indicate that the former historic gas station and waste oil USTs
were the sources for the existing subsurface soil contamination at AOC 43J. Primary contaminants detected
in the subsurface soil samples were BTEX, 2-methylnaphthalene, naphthalene, phenanthrene, pyrene, and
TPHC. These volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) are documented
constituents of gasoline and oils. Based upon these results, it appears that leaks and spills from both
former USTs have caused the existing soil contamination.

Subsurface soil contamination extends south from the former historic gas station and waste oil UST
excavation approximately 180 feet, and is a maximum of 110 feet wide. Subsurface soil contamination does
extend horizontally beyond the southwestern fence line, however, the remaining soil contamination appears
to be within the fenced area of AOC 43J. The majority of contaminated soil was detected at, or just
below, the water table, at depths ranging from 7 to 12 feet bgs. Distribution of the subsurface soil
contamination supports the USTs as source areas. Subsurface soil contamination was detected at higher
concentrations at the water table, with decreasing concentrations as sample depth increased. Based on
soil boring data, it appears that contamination has not migrated vertically to the bedrock surface.

2. Groundwater

a. AOC 43G

Distribution and concentrations of VOCs (primarily BTEX) and SVOCs detected in 1994/1995 groundwater
samples are in agreement with pre-1994 data. The distribution of the groundwater contamination appears to
confirm that the groundwater contaminant source is the apparent residual soil contamination below the
former gasoline USTs in Area 2, and potentially the former residual soil contamination detected in Area
3. The intrinsic bioremediation assessment will further determine the distribution of the groundwater
contamination below the former gasoline USTs, including bedrock.

The highest concentrations of BTEX and polynuclear aromatic hydrocarbons (PAHs) were detected in the
monitoring wells directly downgradient of Areas 2 and 3 (AAFES-1D, AAFES-2, AAFES-6, XGM-93-02X,
XGM-94-03X, and XGM-94-04X). Benzene concentrations were detected up to 2,000 Ig/L in AAFES-2 in the last
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RI groundwater sampling round (Round 6) (see Figure 3 in Appendix A).

BTEX was detected in several downgradient (XGM-94-06X, XGM-94-08X and XGM-94-10X) and crossgradient
(XGM-94-03X and XGM-94-09X) monitoring wells. Concentrations exceeded drinking water standards in
XGM-94-10X XGM-94-08X, and XGM-94-07X with the highest concentration being 7.7 Ig/L at XGM-94-10X.

The RI groundwater results indicate that the highest concentrations of groundwater contamination appear
to be in the groundwater at the base of the slope directly south (downgradient) of Areas 2 and 3. The
groundwater contamination concentrations decrease with distance (in the downgradient and crossgradient
directions) from this area.

Although concentrations of inorganic analytes generally exceed Fort Devens background concentrations in
unfiltered samples, this appears to be a result of total suspended solids (TSS) in the unfiltered sample
rather then dissolved site-related contamination. In addition, the distribution of detected inorganic
analytes does not indicate that their presence is related to past activities at AOC 43G.

A complete presentation of the groundwater results can be found in Section 7 of the AOC 43G Final RI
report.

b. AOC 43J

Distribution and concentrations of VOCs detected in 1994/1995 groundwater samples are in agreement with
pre-1994 off-site laboratory data and the field analytical data. The distribution of the groundwater
contamination appears to confirm that the past sources of groundwater contamination were the former
historic gas station and waste oil USTs, and that the existing source of the groundwater contamination is
the residual soil contamination at and directly downgradient of the former UST locations.

BTEX, chlorinated solvents, and several SVOCs were detected in several monitoring wells downgradient
(2446-02, 2446-03, XJM-93-04X, XJM-94-05X, XJM-94-06X, and XJM-94-09X) of the former UST excavations (see
Figure 3 in Appendix A). Benzene concentration were detected up to 300 I/L at XJM-94-05X in the last RI
groundwater sampling round (Round 6).

Groundwater contaminant distribution is similar to soil contaminant distribution, except that low
concentrations of fuel-related contaminants have been spread southeastward (toward XJM-94-08X) by
seasonal fluctuations in groundwater flow direction.

Although concentrations of inorganic analytes were generally above Fort Devens background concentrations
in unfiltered samples, it appears that these results were caused by TSS rather than dissolved
site-related contamination.

A complete presentation of the groundwater results can be found in Section 7 of the AOC 43J Final RI
report.

C. Sediment

AOC 43G

One sediment sample (XGD-93-02X) was collected from the storm water collection outfall located east of
AOC 43G during the SSI (see Figure 2 in Appendix A). A surface water sample was not collected from this
location because there was insufficient surface water volume available at the time of sample collection.

No VOCs or SVOCs were detected in XGD-93-02X. TPHC was detected at 448 micrograms per gram (Ig/g).
Several inorganic analytes were detected, and the total organic carbon (TOG) concentration was 8,970
Ig/g.

VI. SUMMARY OF SITE RISKS

A. AOC 43G

A human health risk assessment has been conducted to evaluate potential health risks to individuals under
current or foreseeable future site conditions at AOC 43G. The risk assessment is consistent with relevant
guidance and standards developed by USEPA and incorporates data from the scientific literature used in
conjunction with professional judgment. A commercial/industrial worker scenario was used to assess
potential human health risks associated with contaminants detected in soil, sediment and groundwater
because the future reuse of this area will remain similar to its present use. Because of the urbanized
nature of this site and the lack of exposure pathways (the site is paved), an ecological risk assessment
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was not performed. Tables 1 and 2 in Appendix B summarize the statistics used in the risk assessment. A
complete presentation of the risk assessment can be found in Section 9 of the Final RI report.

The assessment for AOC 43G consists of the following components:

• Selection of Chemicals of Potential Concern (CPCs)
• Exposure Assessment
• Toxicity Assessment
• Risk Characterization
• Uncertainty Evaluation
• Summary and Conclusions

1. Subsurface Soil

Potential human health risks associated with exposure to subsurface soil at Areas 2 and 3 of AOC 43G were
evaluated in the Final RI report. Potential human health risks associated with exposure to subsurface
soil in Area 1 were evaluated in the Final SI report and were not presented in the RI risk assessment.
The primary CPCS in soil were ethylbenzene, toluene, xylene, PAHs, and inorganics. The evaluated exposure
scenario was for a utility/maintenance worker. Estimated carcinogenic risks did not exceed the USEPA
target risk range or MADEP Massachusetts Contingency Plan (MCP) risk management level. Similarly,
potential noncarcinogenic risks did not exceed the USEPA and MADEP MCP target level.

2. Groundwater
Risks associated with exposure to groundwater were evaluated for unfiltered groundwater representing the
source area and for unfiltered groundwater identified as downgradient. The receptor evaluated was a
future commercial/industrial worker. Estimated carcinogenic risks were at the upper end or exceeded the
USEPA risk range of 1x10 -4 to 1x10 -6 for exposure to both mean and maximum concentrations of CPCs in
source area groundwater (1x10 -4 and 6x10 -4, respectively). Arsenic and benzene were the primary
contributors to the excess risk in both cases. At maximum concentrations both arsenic and benzene
produced individual risks above 1x10 -4. In downgradient groundwater, only exposure to maximum
concentrations produced a cancer risk exceeding the USEPA range. Arsenic contributed 94 percent of the
risk of 2x10 -4 for maximum concentrations.

Risks were estimated for commercial/industrial worker exposure to filtered groundwater assuming that
concentrations of organic CPCs remain the same as in unfiltered groundwater. Estimated carcinogenic risks
were at the upper end or exceeded the USEPA target risk range of 1x10 -4 to 1x10 -6 for exposure to both
mean and maximum concentrations of CPCs in source area filtered groundwater (1x10 -4 and 4x10 -4,
respectively). Arsenic and benzene were the primary contributors to the excess risk in both cases. At
maximum concentrations both arsenic and benzene produced individual risks above 1x10 -4. In downgradient
filtered groundwater, exposure to both mean and maximum concentrations produced risks within the USEPA
range (5x10 -5 and 9x10 -5, respectively).

If the modified cancer slope factor (CSF) for arsenic was used to estimate excess lifetime cancer risks,
the cancer risks associated with exposure to both average and maximum concentrations of arsenic in
filtered and unfiltered groundwater would fall below 1x10 -4.

Estimated noncarcinogenic risks exceeded the USEPA target level of 1 for both source area and
downgradient unfiltered groundwater at mean and maximum concentrations. Hazard Indices (His) for the
source area are 36 and 98 for exposure to mean and maximum concentrations, respectively. Benzene,
manganese, iron, and arsenic are the primary risk contributors for source area groundwater. His for
downgradient groundwater are 11 and 21 for mean and maximum concentrations, respectively. Manganese and
benzene are the primary contributors for downgradient groundwater. Individual hazard guotients (HQs) for
the primary contributors in both source area and downgradient groundwater all exceed the USEPA target
level of 1.

A comparison of detected concentrations of CPCs in source area and downgradient groundwater to federal
and state drinking water standards and guidelines showed several exceedances. In source area groundwater,
the following CPCs were detected at concentrations above a federal or state standard: xylenes, benzene,
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ethylbenzene, arsenic, lead, nickel aluminum, iron, manganese, and sodium. In downgradient groundwater,
detected concentrations of benzene, aluminum, iron, manganese and sodium exceed federal or state drinking
water standards or guidelines.

B. AOC 43J

A human health risk assessment has been conducted to evaluate potential health risks to individuals under
current or foreseeable future site conditions at AOC 43J. The risk assessment is consistent with relevant
guidance and standards developed by USEPA and incorporates data from the scientific literature used in
conjunction with professional judgment. Because of the urbanized nature of this site and the lack of
exposure pathways, an ecological risk assessment was not conducted. Table 3 in Appendix B summarizes the
statistics used in the risk assessment. A complete presentation of the risk assessment can be found in
Section 9 of the Final RI report.

The assessment for AOC 43J consists of the following components:

Selection of CPCs
• Exposure Assessment
• Toxicity Assessment
• Risk Characterization
• Uncertainty Evaluation
• Summary and Conclusions

1. Subsurface Soil

Potential health risks associated with exposure to subsurface soil at the source area and the perimeter
area of AOC 43J were evaluated in the Final RI report. The primary CPCs identified in soil were
ethylbenzene, toluene, xylene, noncarcinogenic PAHs, and inorganics. The exposure scenarios evaluated
were for a utility/maintenance worker and a construction worker. Estimated carcinogenic risks did not
exceed the USEPA risk range or MADEP MCP risk level. Similarly, potential noncarcinogenic risks did not
exceed the USEPA and MADEP MCP target level.

2. Groundwater

Risks associated with exposure to unfiltered and filtered groundwater were evaluated for groundwater
representing the source area and for groundwater identified as downgradient. The receptor evaluated was a
future commercial/industrial worker. Estimated carcinogenic risks for unfiltered groundwater exceeded the
USEPA target risk range of 1x10 -4 to 1x10 -6 for exposure to both mean and maximum concentrations of
CPCs in source area groundwater (3x10 -4 and 6x10 -4, respectively). Arsenic was the primary contributor
to risk exceeding the 1x10 -4 risk level. Assuming exposure to maximum concentrations, benzene and carbon
tetrachloride produced individual risks above 1x10 -5. In unfiltered downgradient groundwater, estimated
carcinogenic risks were within the USEPA target risk range.

Risks were estimated for commercial/industrial worker exposure to filtered groundwater assuming that
concentrations of organic CPCs remain the same as in unfiltered groundwater. Estimated carcinogenic risks
exceeded the USEPA risk range of 1x10 -4 to 1x10 -6 for exposure to both mean and maximum concentrations
of CPCs in source area groundwater (2x10 -4 and 5x10 -4, respectively). Arsenic and benzene were the
primary contributors to the excess risk for mean concentrations, while arsenic, benzene, and carbon
tetrachloride were primary contributors at maximum concentrations. At both mean and maximum
concentrations, only arsenic produced individual risks above 1x10 -4. In downgradient groundwater,
exposure to both mean and maximum concentrations produced risks within the USEPA range (1x10 -5 and 3x10
-5, respectively).

If the modified CSF for arsenic was used to estimate excess lifetime cancer risks, then the cancer risks
associated with exposure to both average and maximum concentrations of arsenic in unfiltered and filtered
groundwater would fall below 1x10 -4.

Estimated noncarcinogenic risks exceeded the USEPA target level of 1 for both source area and
downgradient unfiltered groundwater at mean and maximum concentrations. His for the source area are 25
and 53 for exposure to mean and maximum concentrations, respectively. Benzene, manganese, iron, and
arsenic are the primary contributors for source area groundwater. His for downgradient groundwater are 2
and 7 for mean and maximum concentrations, respectively. Manganese and benzene are the primary
contributors for downgradient groundwater. Individual HQs for the primary contributors in both source
area and downgradient groundwater all exceed the USEPA target level of 1.
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For filtered groundwater, estimated noncarcinogenic risks exceeded the USEPA target level of 1 for both
source area and downgradient groundwater at mean and maximum concentrations. His for the source area are
24 and 52 for exposure to mean and maximum concentrations, respectively. Benzene and manganese are
primary contributors at mean concentrations, while benzene, manganese and arsenic are the primary
contributors for maximum concentrations of filtered source area groundwater. His for downgradient
groundwater are 2 and 6 for mean and maximum concentrations, respectively. Manganese is the only
contributor with an HQ exceeding 1.

A comparison of detected concentrations of CPCs in source area and downgradient groundwater to federal
and state drinking water standards and guidelines showed several exceedances. In source area groundwater,
the following CPCs were detected at concentrations above a federal or state standard or guideline:
benzene, ethylbenzene, toluene, carbon tetrachloride, chloroform, arsenic, cadmium, lead, sodium,
aluminum, iron, and manganese. In downgradient groundwater, detected concentrations of benzene,
chloroform, aluminum, iron, and manganese exceed federal or state drinking water standards or guidelines.

VII. DEVELOPMENT AND SCREENING OF ALTERNATIVES

A. Statutory Requirements/Response Objectives

Under its legal authorities, the Army's primary responsibility at Superfund sites is to undertake
remedial actions that are protective of human health and the environment. In addition, Section 121 of
CERCLA establishes several other statutory reguirements and preferences, including: a reguirement that
the remedial action, when complete, must comply with all federal and more stringent state environmental
standards, reguirements, criteria, or limitations, unless a waiver is invoked; a reguirement that a
remedial action be cost-effective and use permanent solutions and alternative treatment technologies or
resource recovery technologies to the maximum extent practicable; and a preference for remedies in which
treatment permanently and significantly reduces the toxicity, mobility, or volume of hazardous substances
as a principal element. 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 response objectives were developed to aid in the development and
screening of alternatives. These remedial response objectives were developed to mitigate existing and
future potential threats to human health and the environment. The response objectives are:

• Protect potential commercial/industrial receptors, located on Army property, from exposure
to contaminated groundwater having chemicals in excess of maximum contaminant levels (MCLs).

• Protect potential commercial/industrial receptors located off Army property from exposure to
groundwater having chemicals in excess of MCLs.

• Prevent contaminated groundwater having chemicals in excess of MCLs from migrating off Army
property.

Response objectives were not identified for surface soil, subsurface soil, or air. The risk assessments
did not identify potential risks from exposure to surface soil or subsurface soil, and ambient air
monitoring during the RI did not identify airborne contaminants.

B. Technology and Alternative Development and Screening

CERCLA and the National Oil and Hazardous Substances Pollution Contingency Plan (NCP) set forth the
process by which remedial actions are evaluated and selected. In accordance with these reguirements, a
range of alternatives were developed for both AOC 43G and 43J. The NCP reaffirms CERCLA's preference for
permanent solutions that use treatment technologies to reduce the toxicity, mobility, and volume of
hazardous substances to the maximum extent practical. With respect to source control, the contaminated
soil found below the former gasoline USTs at AOC 43G was found to be 20 to 30 feet bgs. The excavation
and treatment of soil from such a depth was determined to be impractical in the FS. However, additional
investigation will be conducted as part of the intrinsic bioremediation assessment. The investigation
will assess the nature and distribution of contaminants below the former gasoline USTs, and the potential
effects on the intrinsic bioremediation alternative.

The residual soil contamination detected at AOC 43J was found to be at/or below groundwater contaminant
concentration. Because of this, the excavation of the residual soil contamination would not aid in the
natural biodegradation of the site contaminants.
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With respect to groundwater, the FS for AOC 43G and the FS for AOC 43J developed several remedial
alternatives that attain site-specific cleanup levels using different technologies and a No Action
alternative. The alternatives in each FS used intrinsic bioremediation as the primary remedial action,
with additional technologies added to reduce the time needed to attain risk-based contaminant levels.
Except for the No Action alternative, all the alternatives also included institutional controls,
long-term maintenance, and environmental monitoring programs.

Section 3 of each FS identified, assessed, and screened technologies and process options based on
implementability, effectiveness, and cost. In Section 4 of each FS, these technologies and process
options were combined into the candidate alternatives listed below for each AOC.

1. AOC 43G

• Alternative 1: No Action

• Alternative 2A: Intrinsic Bioremediation

• Alternative 2B: Intrinsic Bioremediation/Soil Venting of Gasoline UST Soils

• Alternative 3: Groundwater Collection and Treatment/Intrinsic Bioremediation

• Alternative 4: Intrinsic Bioremediation/Hydraulic Containment

• Alternative 5: Groundwater Collection and Treatment/Soil Treatment

2. AOC 43J

• Alternative 1: No Action

• Alternative 2: Intrinsic Bioremediation

• Alternative 3: Intrinsic Bioremediation/Passive In-Situ Bioremedial Containment

• Alternative 4: Intrinsic Bioremediation/Hydraulic Containment

The alternatives were then evaluated and screened in Section 4 of each FS based on implementability,
effectiveness, and cost, as described in Section 300.430(e)(4) of the NCP. From this screening process,
each remedial alternatives was retained for detailed analysis.

VIII. DESCRIPTION OF ALTERNATIVES

This section provides a narrative summary of each alternative evaluated in detail in the FS completed for
AOC 43G and AOC 43J. A detailed assessment of each alternative can be found in Sections 4 and 5 in each
AOC's FS report.

A. AOC 43G

1. Alternative 1: No Action

The No Action alternative serves as a baseline alternative with which to compare other remedial
alternatives for AOC 43G. The No Action alternative does not contain any additional remedial action
components to reduce or control potential risks. Existing activities to maintain existing systems and
monitor for potential contaminant migration would be discontinued. The No Action alternative does not
reguire any capital or operation and maintenance (O&M) expenditures.

2. Alternative 2A: Intrinsic Bioremediation

Intrinsic bioremediation is the principal component proposed in Alternative 2A to prevent CPCs that
exceed groundwater cleanup levels from potentially migrating off Army property or an area located
sufficiently inside the boundary in which compliance will be determined, according to cleanup criteria
stated in the Record of Decision, that at minimum will meet drinking water standards. The installation of
additional monitoring wells and implementation of a long-term groundwater monitoring program will enable
assessment of the biodegradation progress and permit detection of any potential migration of contaminants
beyond the Devens Reserve Forces Area boundary. Key components of this alternative include:
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• intrinsic bioremediation

• intrinsic bioremediation assessment data collection and groundwater modeling

• installing additional groundwater monitoring wells

• long-term groundwater monitoring

annual data reports to USEPA and MADEP

• five-year site reviews

Direct capital costs for Alternative 2A include the cost to collect the intrinsic bioremediation
assessment data, perform the modeling, mobilize a drill rig and install new groundwater monitoring wells.
O&M costs include maintenance of the groundwater monitoring wells, long-term groundwater monitoring, and
five-year site reviews.

Total Direct and Indirect Costs: $39,000
Present Worth of O&M costs: $406,300
Total Present Worth: $445,300 (30 years)

3. Alternative 2B: Intrinsic Bioremediation/Soil Venting of Gasoline UST Soils

Like Alternative 2A, intrinsic bioremediation is the principal component proposed in Alternative 2B to
prevent CPCs that exceed groundwater cleanup levels from potentially migrating off Army property or an
area located sufficiently inside the boundary in which compliance will be determined, according to
cleanup criteria stated in the Record of Decision, that at minimum will meet drinking water standards.
However, Alternative 2B also includes installation of an soil vapor extraction (SVE) system to reduce
residual contaminant concentrations in soils below the former gasoline USTs. The objective of the SVE
system is to remediate the gasoline UST vadose zone soils to prevent further potential contamination of
the aguifer. The soils that contain VOCs may contribute to groundwater contamination during periods of
high water table conditions. Minimizing the potential re-contamination of groundwater will improve the
effectiveness of intrinsic bioremediation. The following specific actions are included in Alternative 2B:

• intrinsic bioremediation
• intrinsic bioremediation assessment data collection/groundwater modeling
• installing additional groundwater monitoring wells
• SVE treatment system installation and operation
• soil vapor monitoring
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews

Direct capital costs for Alternative 2B include all the costs discussed for Alternative 2A plus expenses
incurred for design, construction, and maintenance of the SVE system.

O&M costs for the SVE system include biweekly site visits by a technician, carbon use and disposal,
monthly gas chromatograph (GC) analysis of the air streams and measurements from the SVE monitoring
wells.

Total Direct and Indirect Costs: $137,600
Present Worth of O&M costs: $473,900
Total Present Worth: $611,500 (30 years)

4. Alternative 3: Groundwater Collection and Treatment/Intrinsic Bioremediation

Alternative 3 for AOC 43G is designed to reduce potential future human health risks by using groundwater
extraction to hydraulically intercept and to treat the contaminant plume immediately downgradient of the
source areas. Intrinsic bioremediation would be used to degrade CPCs below PRGs farther downgradient or
to minimize the potential for further migration of the plume. This alternative is similar to Alternative
2A except the plume near the source would be intercepted hydraulically rather than relying on intrinsic
bioremediation to treat the plume near the source area. Based on the continual source simulation of the
solute transport model, more then 30 years is expected to be reguired to remove all the contamination in
the aguifer using pumping remediation and intrinsic bioremediation (Appendix C of the Final FS). The
CERCLA default value of 30 years was used for cost estimating purposes. Extraction wells would be
positioned within the higher contaminated portion of the plume and spaced to intercept the plume from the
source area. The following specific actions are included in Alternative 3:
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• intrinsic bioremediation
• intrinsic bioremediation assessment data collection and design
• groundwater treatment facility construction
• groundwater treatment facility operation and maintenance
• installing additional groundwater monitoring wells
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews

Direct capital costs for Alternative 3 include the costs to collect the predesign data, perform
hydrogeologic and intrinsic biodegradation modeling, and to design and construct the groundwater
extraction/treatment system described above. Components include the building, equipment, extraction
wells, trenching, and connection to the sanitary sewer. Also included are expenses for mobilizing a drill
rig to install new groundwater monitoring wells.

O&M costs for the groundwater extraction and treatment facility include weekly site visits by a
technician, carbon use of approximately 21 change-outs per year (based on a VOC concentration equivalent
to 4.4 milligrams per liter [mg/L] of benzene), disposal of the bag filters as a special waste, monthly
VOC sampling and analysis, reporting, and waste water treatment facility (WWTF) user fee. Other O&M costs
include long-term groundwater monitoring, and five-year site reviews.

Total Direct and Indirect Costs: $257,600
Present Worth of O&M costs: $1,444,900
Total Present Worth: $1,702,500

5. Alternative 4: Intrinsic Bioremediation/Hydraulic Containment

• intrinsic bioremediation
• installing passive in-situ bioremediation wells
• passive insitu bioremediation system maintenance
• intrinsic bioremediation assessment data collection and design
• groundwater treatment facility construction
• groundwater treatment facility operation and maintenance
• installing additional groundwater monitoring wells
• long-term groundwater monitoring
annual data reports to USEPA to MADEP
• five-year site reviews

In addition to cost items listed for Alternative 3, Alternative 4 direct capital costs include expenses
for predesign treatability testing and installation of 20 passive bioremediation wells and 16
piezometers. Additional O&M costs include purchase of the oxygen-releasing compound and nutrients, and
maintenance of these wells. Maintenance expense assumes five oxygen-releasing compound/nutrient exchanges
and one surge/acid treatment per year.

Total Direct and Indirect Costs: $387,400
Present Worth of O&M costs: $2,139,800
Total Present Worth: $2,527,200 (30 years)

6. Alternative 5: Groundwater Collection and Treatment/Soil Treatment

Alternative 5 involves installation of a groundwater extraction and treatment system as detailed in
Alternative 4. As previously discussed in Alternative 4, residual contamination may be left on the soil
above the water table when the groundwater in the plume area is lowered during groundwater extraction.
Alternative 4 includes installation of an SVE system to remediate contaminated soils which will be left
above the lowered groundwater table. The objectives of groundwater extraction and treatment are: a) to
halt/minimize the migration of the contamination plume (hydraulic control), and b) to remediate the
aquifer. The objective of soil venting is to remediate the vadose zone and to prevent recontamination of
the groundwater upon rebounding of the aquifer. The combination of groundwater extraction and treatment,
SVE, and intrinsic bioremediation will minimize the potential of off-site migration of groundwater CPCs
and remediate site soil and groundwater. The following specific actions are included in Alternative 5:
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intrinsic bioremediation assessment data collection and design
SVE treatment system installation
groundwater treatment facility construction
installing additional groundwater monitoring wells
groundwater treatment facility O&M
soil monitoring
long-term groundwater monitoring
five-year site reviews
annual data reports to USEPA and MADEP
intrinsic bioremediation
Direct capital costs for Alternative 5 include all the costs discussed for Alternative 4 plus expenses
incurred for pilot testing, design, and construction of the SVE system.

O&M costs for the SVE system include weekly site visits by a technician, carbon use and disposal, monthly
GC analysis of the air streams, semi-annual measurements from the soil vapor monitoring wells and
reporting over a two year period. O&M costs included for Alternative 4 also apply to Alternative 5.
Total Direct and Indirect Costs:
Present Worth of O&M costs:
Total Present Worth:
$388,000
$1,489,900
$1,877,900 (27 years treatment/29 years monitoring)
B.
AOC 43J
1.
Alternative 1: No-Action
The No Action alternative does not contain any remedial action components beyond the existing site
conditions to reduce or control potential risks. No institutional controls would be implemented to
prevent future human exposure, and existing activities to maintain existing systems and monitor for
potential future migration of site-related contaminants of Army property. Alternative 1 is developed to
provide a baseline for comparison with the other remedial alternatives. The No Action alternative does
not require any capital or O&M expenditures.

2. Alternative 2: Intrinsic Bioremediation

Intrinsic bioremediation is the principal component in Alternative 2 that is proposed to reduce
contaminants on Army property to below PRGs, and also to prevent potential migration of contaminants
above PRGs off Army property. The installation of additional monitoring wells and implementation of a
long-term groundwater monitoring program will enable assessment of the biodegradation progress and permit
detection of any potential migration of contaminants beyond the Army boundary. Key components of this
alternative include:
• intrinsic bioremediation
• intrinsic bioremediation assessment data collection and groundwater modeling
• installing additional groundwater monitoring wells
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews

Direct capital costs for Alternative 2 include the cost to collect the intrinsic bioremediation
assessment data, perform the modeling, mobilize a drill rig and install new groundwater monitoring wells.
Costs for O&M include maintenance of the groundwater monitoring wells, long-term groundwater monitoring,
and five-year site reviews.
Total Direct and Indirect Costs:
Present Worth of O&M costs:
Total Present Worth:
$47,200
$394,500
$441,700
(27 years treatment/29 years monitoring)
3. Alternative 3: Intrinsic Bioremediation/Passive In-situ Bioremedial Containment

Alternative 3 for AOC 43J is designed to reduce potential future human health risks. In addition to the
components of Alterative 2, this alternative provides installation of passive in-situ bioremediation
wells to reduce potential future risk to downgradient receptors from potentially contaminated
groundwater. The following specific actions are included in Alternative 3:
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• intrinsic bioremediation
• installing passive bioremediation wells
• passive in-situ bioremediation system maintenance
• intrinsic bioremediation assessment data collection and groundwater modeling
• installing additional groundwater monitoring wells
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews

In addition to cost items listed for Alternative 2 above, Alternative 3 direct capital costs include
expenses for predesign treatability testing and installation of 20 passive bioremediation wells and 16
piezometers. Additional O&M costs include purchase of the oxygen releasing compound and nutrients, and
maintenance of these wells.

Maintenance expense assumes five oxygen releasing compound/nutrient exchanges and one surge/acid
treatment per year.

Total Direct and Indirect Costs: $134,600
Present Worth of O&M costs: $1,003,400
Total Present Worth: $1,138,000 (27 years treatment/29 years monitoring)

4. Alternative 4: Intrinsic Bioremediation/Hydraulic Containment

Alternative 4 for AOC 43J is designed to reduce potential future human health risks by using intrinsic
bioremediation to degrade CPCs below groundwater cleanup levels on-site and using groundwater extraction
and treatment to hydraulically contain and also to treat the contaminant plume. This alternative is
similar to Alternative 3, except the plume would be contained hydraulically rather than by aerobic
biodegradation to reduce potential future risk to downgradient receptors. Calculations based on site soil
and contaminant characteristics reveal that up to 56 years may be required to remove all the
contamination in the aguifer using pumping remediation alone (no abiotic removal or biological
degradation effects) (Appendix D of the Final FS). Intrinsic bioremediation is expected to reduce CPCs to
below groundwater cleanup levels in less time as will be detailed below. Therefore, the groundwater
extraction and treatment component in this alternative serves more for hydraulic containment of the
contaminant plume while reduction of contaminant concentrations would be shared both by intrinsic
bioremediation and groundwater extraction. Extraction wells would be positioned within the higher
contaminated portion of the plume to maximize treatment efficiency for this alternative. The following
specific actions are included in Alternative 4:

• intrinsic bioremediation
• intrinsic bioremediation assessment data collection and design
• groundwater treatment facility construction
• groundwater treatment facility operation and maintenance
• installing additional groundwater monitoring wells
• long-term groundwater and soil monitoring
annual data reports in USEPA and MADEP
• five-year site reviews

A cost estimate was prepared for Alternative 4 to assist in selecting a remedial alternative. Remedial
action is expected to exceed the 30-year default period specified in USEPA guidance for cost analyses
purposes. However, because the remedial time frames for Alternatives 2, 3, and 4 were evaluated using the
same or similar modeling techniques and assumptions, the actual estimated time of 36 years (38 years for
groundwater monitoring) will be used so that the costs between alternatives may be evaluated on an equal
basis, (i.e., Alternatives 2 and 3 are expected to take up to 27 years for site mitigation). Comparing
costs incurred for this period with costs incurred for a default period of 30 years for Alternative 4
would appear to be a biased analysis.

Direct capital costs for Alternative 4 include the costs to collect the predesign data, perform
hydrogeologic modeling, and to design and construct the groundwater extraction/treatment system described
above. Components include the building, equipment, extraction wells, trenching, and connection to the
sanitary sewer. Also included are expenses for mobilizing a drill rig to install new groundwater
monitoring wells.

O&M costs for the groundwater extraction and treatment facility include weekly site visits by a
technician, carbon use of four to five change-outs per year (based on a VOC concentration equivalent to
2.9 mg/L of benzene), disposal of the bag filters as a special waste, monthly VOC sampling and analysis,
reporting, and WWTF user fee. Other O&M costs include long-term groundwater monitoring (analysis for CPCs
once per year) , long-term soil sampling (assumed frequency one sampling round of 10 soil samples each,
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every five years) and five-year site reviews.

Total Direct and Indirect Costs: $270,100
Present Worth of O&M costs: $1,433,700
Total Present Worth: $1,703,800

IX. SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES

Section 121(b)(1) of CERCLA presents several factors that at a minimum the Army is required to consider
in its assessment of alternatives. Building upon these specific statutory mandates, the NCP articulates
nine evaluation criteria to be used in assessing the individual remedial alternatives. The nine criteria
are used to select a remedy that meets the goals of protecting human health and the environment,
maintaining protection over time, and minimizing untreated waste.

A detailed analysis was performed on the alternatives using the nine evaluation criteria to select a site
remedy. Specific discussion regarding this analysis is provided in Section 5 of each FS report.
Definitions of the nine criteria are provided below:

Threshold Criteria

The two threshold criteria described below must be met in order for an alternative to be eligible for
selection in accordance with the NCP.

• Overall Protection of Human Health and the Environment - Assesses how well an alternative,
as a whole, achieves and maintains protection of human health and the environment.

• Compliance with Applicable or Relevant and Appropriate Reguirements (ARARs) - Assesses how
the alternative complies with location-, chemical-, and action-specific ARARs, and whether a
waiver is required or justified.

Primary Balancing Criteria

The following five criteria are used to compare and evaluate the elements of alternatives that meet the
threshold criteria.

• Long-Term Effectiveness and Permanence - Evaluates the effectiveness of the alternative in
protecting human health and the environment after response objectives have been met. This
criterion includes consideration of the magnitude of residual risks and the adequacy and
reliability of controls.

• Reduction of Toxicily, Mobility, and Volume Through Treatment - Evaluates the effectiveness
of treatment processes used to reduce toxicity, mobility, and volume of hazardous
substances. This criterion considers the degree to which treatment is irreversible, and the
type and quantity of residuals remaining after treatment.

• Short-Tenn Effectiveness - Examines the effectiveness of the alternative in protecting human
health and the environment during the construction and implementation of a remedy until
response objectives have been met. Considers the protection of the community, workers, and
the environment during implementation of remedial actions.

• Implementability - Assesses the technical and administrative feasibility of an alternative
and availability of required goods and services. Technical feasibility considers the ability
to construct and operate a technology and its reliability, the ease of undertaking
additional remedial actions, and the ability to monitor the effectiveness of a remedy.
Administrative feasibility considers the ability to obtain approvals from other parties or
agencies and extent of required coordination with other parties or agencies.

• Cost - Evaluates the capital, and operation and maintenance costs of each alternative.

Modifying Criteria

The modifying criteria are used on the final evaluation of remedial alternatives generally after the Army
has received public comments on the FS and proposed plan.
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• State Acceptance - This criterion considers the state's preferences among or concerns about
the alternatives, including comments on ARARs or the proposed use of waivers.

• Community Acceptance - This criterion considers the communities preferences among or
concerns about the alternatives.

Following the detailed analysis of each individual alternative, the Army conducted a comparative
analysis, focusing on the relative performance of each alternative against the nine criteria. Table 5-1
in each FS report summarizes the comparative analysis. This comparative analysis of the alternatives for
each AOC are also summarized below.

A. AOC 43G.

1. Overall Protection of Human Health and the Environment

This criterion, according to CERCLA must be met for a remedial alternative to be chosen as a final site
remedy. At AOC 43G, groundwater sampling has shown that contaminants exceed PRGs on Army property;
however, no current commercial/industrial exposure to groundwater exists because there are no drinking
water wells installed on-site. Also, no future exposure to groundwater on-site is anticipated. The site
is to remain Army property and will continue to be used to support Army Reserve activities. There are no
future plans to install water supply wells on-site to support these activities. Groundwater analysis
results indicate that intrinsic biodegradation is likely occurring naturally at AOC 43G. Should the Army
change the use at either AOC, additional assessment and/or remedial actions may be reguired based upon
the changed risk factors resulting from this change in use. In addition, if the Army transfers either
site by lease or deed then an BBS will need to be conducted, and a determination will be made by the Army
and USEPA that the selected remedy remains protective of human health and the environment. The BBS will
be provided to the USEPA and MADEP for comment.

Calculations reveal that concentrations exceeding groundwater cleanup levels will not likely migrate
beyond the Army's boundary, thereby protecting downgradient receptors from future exposure to CPCs.
Calculations also indicate that organic CPCs may potentially be reduced below groundwater cleanup levels
over time on-site as a result of the intrinsic biodegradation process (see Appendix C of the Final FS).
Because intrinsic biodegradation is a naturally occurring process, all alternatives consider it as a
remedial component. However, the degree to which each alternative relies on intrinsic bioremediation
varies. Some of the alternatives rely on backup components to achieve PRGs if intrinsic biodegradation
does not perform as anticipated. Therefore, all alternatives are considered protective of human health
and the environment.

Although Alternative 1 proposes no action, intrinsic bioremediation would likely prevent future potential
exposure to contaminated groundwater. However, there would be no method to assess the protectiveness of
this alternative because there would be no groundwater monitoring performed. Alternative 2A would use
additional data collection, modeling, long-term groundwater monitoring, and five-year site reviews to
ensure that intrinsic bioremediation is protective of human health and the environment. The additional
soil investigation below the former USTs at AOC 43G, will be used to help determine if an SVE system is
needed to aid the intrinsic bioremediation alternative. If the existing groundwater contamination appears
to be migrating off Army property or an area located sufficiently inside the boundary in which compliance
will be determined, according to cleanup criteria stated in the Record of Decision, that at minimum will
meet drinking water standards, the addition of the SVE system will be considered. Alternatives 2B, 3, and
4 add supplemental or backup treatment components in addition to their reliance on intrinsic
bioremediation. Alternative 2B adds soil venting of the soils below the former gasoline USTs to minimize
the potential of groundwater recontamination. Alternative 3 adds groundwater collection and treatment as
a means of intercepting the most contaminated portion of the plume to minimize the potential for
migration of CPCs that exceed MCLs or MMCLs. Alternative 4 uses passive bioremediation (aerobic
treatment) at the plume edge to minimize migration potential. The added technologies in Alternatives 2B,
3, and 4 increase the potential Protection of downgradient receptors, although each could also be added
as additional alternatives upon nonperformance of intrinsic biodegradation without jeopardizing overall
protection of human health and the environment.

2. Compliance with Applicable or Relevant and Appropriate Requirements

CERCLA reguires that the selected alternative also meet a second threshold criterion of compliance with
ARARs, or obtain a waiver if the criterion cannot be met. No location specific ARARs are triggered for
remedial activities at AOC 43G. Organic CPC concentrations could be reduced to below federal and
Massachusetts drinking water Maximum Contaminant Levels (MCLs) and MMCLs by biological degradation
depending upon modeling results and if the source area has been successfully removed. Inorganic CPCs in
groundwater may also revert to more insoluble forms upon reduction of organic concentrations and meet
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MCLs, MMCLs, and Massachusetts Groundwater Quality Criteria (314 CMR 6.00).

Alternatives 2A through 4 would use groundwater monitoring to evaluate long-term effectiveness and the
potential for CPC migration off Army property. Monitoring would be in compliance with substantive
portions of the Massachusetts Hazardous Waste Management Rules 310 CMR 30.660 - 30.670 relating to the
development of a groundwater monitoring plan. Alternatives 2B, 3, and 4 would need to meet additional
action-specific ARARs because of the additional technologies used. Alternative 2B would use a soil
venting treatment system (vapor phase activated carbon) to comply with the Massachusetts Air Pollution
Control Regulations (310 CMR 6.00 - 7.00). These regulations reguire a minimum 95 percent reduction (by
weight) in VOCs in the air effluent air stream. Additionally, spent activated carbon would be tested to
meet disposal reguirements in accordance with Resource conservation and Recovery Act (RCRA) Land Disposal
Restrictions (40 CFR 268). Alternative 3 groundwater treatment discharge would meet the reguirements of
the Clean Water Act, General Pretreatment Program (40 CFR Part 403). Similar to Alternative 2B,
Alternative 3 treatment wastes (spent activated carbon, filtered material, sludge) would be tested for
proper disposal (40 CFR 268). Engineering controls (dust suppression) would be used to comply with
Massachusetts Air Pollution Control Regulations (310 CMR 6.00 - 7.00) which would regulate particulate
emissions during site construction activities. Alternative 4 would be in general compliance with the
Underground Injection Control Program (40 CFR Parts 144 & 146), the Underground Water Source Protection
Standards (310 CMR 27.00) plus those regulations specified for Alternative 3.

3. Long-term Effectiveness and Permanence

This criterion evaluates the magnitude of residual risk and the reliability of controls after response
objectives have been met. In the microbial degradation process of intrinsic bioremediation, the organic
CPCs are converted ultimately to inert compounds such as carbon dioxide, methane, and water. Inorganic
CPCs will revert to more insoluble forms following completion of organic degradation. Because of the
actual degradation/destruction of organic contaminants that occurs in this process, intrinsic
bioremediation provides permanent treatment effectiveness without secondary waste disposal. Alternatives
2B, 3, and 4 which use supplemental technologies (SVE or groundwater extraction and treatment) have
secondary waste (i.e., spent activated carbon and sludge) that will reguire disposal.

4. Reduction of Toxicitv, Mobility, and Volume through Treatment

This criterion evaluates whether the alternatives meet the statutory preference for treatment under
CERCLA. The criterion evaluates the reduction of toxicity, mobility, or volume of contaminants, and the
type and guantity of treatment residuals. All alternatives meet the statutory preference for treatment
under CERCLA, because intrinsic bioremediation is a naturally occurring process for all alternatives
evaluated. Alternatives 2B, 3, and 4 offer supplemental or back-up treatment processes which also
contribute to the reduction of toxicity, mobility and volume of contaminants. Alternatives 2B, 3, and 4
would generate concentrated waste streams (i.e., sludge, filtered material, and/or spent carbon) that
would reguire disposal.

5. Short-term Effectiveness

CERCLA reguires that potential adverse short-term effects to workers, the surrounding community, and the
environment be considered during selection of a remedial action. Major adverse short-term effects to site
workers are not expected for any of the alternatives because all activities can be monitored readily and
engineering control implemented in accordance with a Health and Safety Plan. However, because of more
intrusive activities, monitoring reguirements and construction work, the potential for contaminant
exposure and safety hazards to workers increases with Alternatives 2A, 2B, 3, and 4, respectively.
Alternatives 2B and 3 reguire installation of twice the number of wells reguired by Alternative 2A.
Alternatives 2B, 3, and 4 also utilize active treatment processes that reguire more freguent contact with
contaminated medium during O&M and monitoring activities.

For costing purposes, Alternatives 2A, 2B, 3, and 4 are all assumed to reguire greater than 30 years to
meet remedial objectives.

6. Implementabilitv

This criterion evaluates each alternative's ease of construction and operation and availability of
services, eguipment, and materials to construct and operate the alternative. Also evaluated is the ease
of undertaking additional remedial actions and administrative feasibility.

Although the engineering complexity increases for each alternative (i.e., Alternative 4 > Alterative 3 >
Alternative 2B > Alternative 2A > Alternative 1), engineering and construction services, eguipment, and
materials should be readily available to implement any of the alternatives. Alternatives 2A through 4 all
reguire additional data collection, modeling or pilot testing prior to design and implementation.
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Alternatives 2A through 4 would require additional data collection and intrinsic bioremediation modeling
to refine biodegradation rates following removal of the sand and gas trap with associated soils.
Alternatives 3 and 4 both require additional groundwater pumping tests and hydrogelolgical modeling to
verify flow rates and quantity and placement of extraction wells to hydraulically contain the contaminant
plume. Alternative 4 would also require, as a minimum, laboratory treatability testing to assess
oxygen-releasing compounds and nutrient needs. Limited pilot testing may be required to verify field
application of oxygen-releasing compounds and nutrients.

Groundwater monitoring to assess the success of remedial action is performed easily for all alternatives.
None of the alternatives would limit or interfere with the ability to perform future remedial actions.
All alternatives would require coordination among regulatory agencies to institute the five-year review
process.

7. Cost

There are no costs associated with Alternative 1. Capital, O&M, and present worth costs were estimated
for Alternatives 2A through 4. Cost estimates for these alternatives included similar expense for
long-term groundwater monitoring. As would be expected, Alternatives 2A and 4 are the least and most
expensive alternatives, respectively. The alternative with the lowest capital cost is Alternative 2A
because it does not include extensive construction activities. Alternative 4 has the highest capital cost
because it includes the design and construction of a groundwater extraction/treatment system and passive
bioremediation system. Alternatives 3 and 4 both have high O&M costs because of long-term maintenance of
the groundwater treatment and passive bioremediation systems.

After calculating the present worth for each alternative, the sensitivity of the costs to the estimating
assumptions was evaluated. The total cost associated with all alternatives consist primarily of long-term
O&M and/or groundwater monitoring costs. These long term costs contribute between approximately 75
percent and 90 percent to the overall total cost. A high degree of uncertainty is associated with the
length of time required to reduce contaminants to below PRGs. The effects from possible residual
contamination within the bedrock fractures cannot yet be recognized. A 30-year remediation time was
conservatively used for costing purposes. The estimate of four years for intrinsic bioremediation
("on/off source simulation) is believed to be also based on conservative assumptions, but assumes that
there is no continuous source (see Appendix C in the Final FS). This shorter treatment period would
significantly reduce O&M costs and total present worth costs proportionally for all alternatives. The
relative comparison between alternatives would remain similar. Therefore, further sensitivity analysis to
assess effects from "across the board" remedial action time reduction was not performed for these
alternatives.

It is also noted that expenses incurred for Alternative 4 assume that oxygen-releasing compounds and
nutrient application would be required for the entire 30-year remedial action time period (assumes that
intrinsic biodegradation is not capable of containing the plume for the entire 30 years). Numerous other
scenarios are equally likely and could include: 1) biodegradation within the plume area could occur to
the extent that the contaminant plume would shrink in size within five years, 2) and that maintenance of
the bioremediation wells would not be required for the remaining duration of 25 years that it would take
to reduce CPCs below PRGs. Reducing need for aerobic treatment time would significantly reduce O&M costs
for Alternative 4. The total present worth could be reduced to approximately 30 percent of the full
30-year total present worth.

8. State Acceptance
This criterion addresses whether, based on its review of the RI, FS, and proposed plan, the state concurs
with, opposes, or has no comment on the alternative the Army is proposing as the remedy for AOC 43G. The
Commonwealth of Massachusetts has reviewed the RI, FS, proposed plan, and this Record of Decision and
concurs with the selected remedy.

9. Community Acceptance

This criterion addresses whether the public concurs with the Army's proposed plan. No comments were
received from the community during the public comment period. The Army believes this shows community
acceptance of the proposed plan and selected remedy.
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B. AOC 43J

1. Overall Protection of Human Health and the Environment

This criterion, according to CERCLA, must be met for a remedial alternative to be chosen as a final site
remedy. At AOC 43J groundwater sampling has shown that contaminants exceed groundwater cleanup levels on
Army property; however, no current commercial or industrial exposure to groundwater exists because there
are no drinking water wells installed on site. Also, no future exposure to groundwater on site is
anticipated. The site is to remain Army property and will continue to be used to support Army Reserve
activities. There are no future plans to install water supply wells on site to support these activities.
Groundwater analysis results indicate that intrinsic biodegradation is currently occurring naturally at
AOC 43J.

Calculations indicate that organic CPCs will be reduced below groundwater cleanup levels over time as a
result of the intrinsic biodegradation process. Calculations also reveal that concentrations exceeding
groundwater cleanup levels will not likely migrate beyond the Army's boundary, thereby protecting
downgradient receptors from future exposure to CPCs. Because intrinsic biodegradation is a naturally
occurring process, all alternatives consider it at as a remedial component. However, the degree to which
each alternative relies on intrinsic bioremediation varies. Some of the alternatives rely on redundant or
backup components to achieve groundwater cleanup levels if intrinsic biodegradation does not perform as
anticipated. Therefore, all alternatives are considered protective of human health and the environment.

Although Alternative 1 proposes no action, intrinsic bioremediation would likely result in attainment of
groundwater cleanup levels. However, there would be no method to assess the protectiveness of this
alternative because there would be no groundwater monitoring performed. Alternative 2 would use
additional data collection, modeling, long-term groundwater monitoring, five-year site reviews and
contingencies for additional action to ensure that intrinsic bioremediation is protective of human health
and the environment. Alternatives 3, 4 and 5 add more active response actions as redundant or backup
components in addition to their reliance on intrinsic bioremediation. Alternative 3 adds passive
bioremediation (aerobic treatment) at the plume edge to minimize migration potential. Alternatives 4 and
5 add groundwater extraction/treatment and groundwater extraction/treatment combined with SVE,
respectively. The added technologies in Alternatives 3, 4, and 5 increase the potential protection of
downgradient receptors, although each could also be added as contingency alternatives upon nonperformance
of intrinsic biodegradation, outlined in Alternative 2, without jeopardizing overall protection of human
health and the environment.

2. Compliance with Applicable or Relevant and Appropriate Requirements

CERCLA reguires that the selected alternative also meet a second threshold criterion of compliance with
ARARs, or obtain a waiver if the criterion can not be met. No location-specific ARARs are triggered for
remedial activities at AOC 43J. All alternatives rely on intrinsic bioremediation to comply with
chemical-specific ARARs within the mitigation time-frames presented for each alternative. (Groundwater
extraction and treatment without considering intrinsic biodegradation would reguire a longer time-frame
to comply with ARARs). Organic CPC concentrations will be reduced to below MCLs and MMCLs by biological
degradation. Inorganic CPCs in groundwater will revert to more insoluble forms upon reduction of organic
concentrations and meet MCLs and MMCLs, and the Massachusetts Groundwater Quality Criteria (314 CMR
6.00) .

Alternatives 2 through 5 would use groundwater monitoring to evaluate long-term effectiveness and the
potential for CPC migration off Army property. Monitoring would be in compliance with substantive
portions of the Massachusetts Hazardous Waste Management Rules 310 CMR 30.660 - 30.670 relating to the
development of a groundwater monitoring plan. Alternatives 3 through 5 would need to meet additional
action-specific ARARs because of the additional technologies used. Alternative 3 would be in general
compliance with the Underground Injection Control Program (40 CTR Parts 144 & 146) and Underground Water
Source Protection Standards (310 CMR 27.00). Alternative 4 groundwater treatment discharge would meet the
reguirements of the Clean Water Act, General Pretreatment Program (40 CFR Part 403). Treatment wastes
(i.e., activated carbon, filtered material, and sludge) would be tested to evaluate if they are
classified as a characteristic hazardous waste in accordance with RCRA Land Disposal Restrictions (40 CFR
268). Engineering controls (dust suppression) would be used to comply with Massachusetts Air Pollution
Control Regulations (310 CMR 6.00 - 7.00) which would regulate particulate emissions during site
construction activities. Alternative 5 would use a soil venting gas treatment system to comply with the
Massachusetts Air Pollution Control regulations (310 CMR 7.03). For costing purposes in this FS
evaluation, soil venting gas treatment by vapor phase activated carbon was assumed. The air regulations
reguire a minimum 95 percent reduction (by weight) in VOCs in the air effluent stream. Air monitoring
would be reguired to ensure compliance.
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3. Long-term Effectiveness and Permanence

This criterion evaluates the magnitude of residual risk and the reliability of controls after response
objectives have been met. Alternative 2, as well as all the other alternatives rely on intrinsic
bioremediation to achieve the remedial action objectives within the mitigation time-frames presented for
each alternative. In the microbial degradation process of intrinsic bioremediation, the organic CPCs are
ultimately converted to inert compounds such as carbon dioxide, methane, and water. Inorganic CPCs revert
to more insoluble forms following completion of organic degradation. Because of the degradation/
destruction of organic contaminants that occurs in this process, intrinsic bioremediation provides
permanent treatment effectiveness without secondary waste disposal. Alternative 3 offers no real
long-term advantages over Alternative 2. Once PRGs are achieved, bioremediation wells would no longer be
used to add oxygen releasing compounds and nutrients. Alternatives 4 and 5 which use backup technologies
of groundwater extraction and treatment and SVE have secondary waste (i.e., activated carbon and sludge)
that will require disposal.

Alternatives 4 and 5 would lower the groundwater table by approximately 1 foot. The potential for
groundwater recontamination exists when the groundwater table rebounds after groundwater extraction has
been halted (if the contamination in the vadose zone soil is not reduced). Soil sampling/monitoring would
be performed to evaluate the progressiveness of biodegradation and SVE in the vadose zone for
Alternatives 4 and 5, respectively. Any remaining soil contamination may be difficult to detect because
of the heterogenous nature of soil and contaminant distribution.

Alternatives 2 and 3 do not lower the groundwater table so the potential for groundwater recontamination
is not as likely. All alternatives, except Alternative 1, use long-term groundwater monitoring to ensure
that compliance with groundwater cleanup goals, is reached for three consecutive annual sampling rounds.

4. Reduction of Toxicitv, Mobility, and Volume through Treatment

This criterion evaluates whether the alternatives meet the statutory preference for treatment under
CERCLA. The criterion evaluates the reduction of toxicity, mobility, or volume of contaminants, and the
type and quantity of treatment residuals. All alternatives, including Alternative 1 (No Action), meet the
statutory preference for treatment under CERCLA because intrinsic bioremediation is a naturally occurring
process for all alternatives evaluated. Alternatives 3, 4 and 5 offer back-up treatment processes which
also contribute to the reduction of toxicity, mobility, and volume of contaminants.

Alternatives 4 and 5 would generate concentrated waste streams (i.e., sludge, filtered material, and
spent carbon) that would require disposal.

5_. Short-term Effectiveness

CERCLA requires that potential adverse short-term effects to workers, the surrounding community, and the
environment be considered during selection of a remedial action. Major adverse short-term effects to site
workers are not expected for any of the alternatives because all activities can be readily monitored and
engineering control implemented in accordance with a Health and Safety Plan. However, because of more
intrusive activities, monitoring requirements and construction work, the potential for contaminant
exposure and safety hazards to workers increases with Alternatives 2, 3, 4 and 5, respectively.
Alternative 3 requires installation of over six times the number of wells required by Alternative 2.
Alternatives 4 and 5 utilize active treatment processes that require more frequent contact with
contaminated medium during O&M and monitoring activities.

Alternatives 1, 2, 3, and 5 are expected to require 27 years to meet remedial objectives. Alternative 4
is anticipated to require 36 years to meet remedial objectives. (Remediation times are not inclusive of
the additional two years of groundwater monitoring required for Alternatives 2 through 5.)

6_. Implementabilitv

This criterion evaluates each alternative's ease of construction and operation and availability of
services, equipment, and materials to construct and operate the alternative. Also evaluated is the ease
of undertaking additional remedial actions and administrative feasibility.

Although the engineering complexity increases for each alternative (i.e., Alternative 5 > Alternative 4 >
Alterative 3 > Alternative 2 > Alternative 1), engineering and construction services, equipment, and
materials should be readily available to implement any of the alternatives. Alternatives 2 through 5 all
require additional data collection, modeling or pilot testing prior to design and implementation.
Alternatives 2 and 3 would require additional data collection and intrinsic bioremediation modeling.
Alternative 3 would also require, as a minimum, laboratory treatability testing to assess
oxygen-releasing compounds and nutrient needs. Limited pilot testing may also be required to verify field
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application of oxygen-releasing compounds and nutrients. Alternatives 4 and 5 both reguire groundwater
pumping tests and hydrogeological modeling to verify flow rates and guantity and placement of extraction
wells to hydraulically contain the contaminant plume. Alternative 5 also reguires performing an SVE pilot
test to collect needed design parameters.

Groundwater monitoring to assess the success of remedial action is performed easily for all alternatives.
The soil monitoring that is reguired to assess the potential for groundwater recontamination in
Alternatives 4 and 5 is more difficult to achieve because of the heterogenous soil medium and contaminant
distribution.

None of the alternatives would limit of interfere with the ability to perform future remedial actions.
All alternatives would reguire coordination among regulatory agencies to institute the five-year review
process.

7. Cost

There are not costs associated with Alternative 1. Capital, O&M, and present worth costs were estimated
for Alternatives 2 through 5. Cost estimates for these alternatives included similar expense for
long-term groundwater monitoring. As would be expected, Alternatives 2 and 5 are the least and most
expensive alternatives, respectively. The alternative with the lowest capital cost is Alternative 2
because it does not include extensive construction activities. Alternative 5 has the highest capital cost
because it includes the design and construction of a groundwater extraction/treatment system and SVE
system. Alternatives 4 and 5 both have high O&M costs because of long-term maintenance of the groundwater
treatment and SVE systems. Alternative 3 also has a relatively high O&M cost because of long-term
oxygen-releasing compound application and nutrient addition and well maintenance. Total present worth
cost for Alternative 4 was less than Alternative 5 even though remedial action time for Alternative 4 is
expected to be nine years longer than for Alternative 5. This is because of the expense for SVE O&M is
greater than the O&M costs for operating the extraction system to keep the groundwater table depressed
(assumes no groundwater treatment reguired after 27 years).

After calculating the present worth for each alternative, the sensitivity of the costs to the estimating
assumptions was evaluated. The total cost associated with all alternatives consist primarily of long-term
O&M and/or groundwater monitoring costs. These long term costs contribute between 80 percent and 89
percent to the overall total cost. A relative high degree of uncertainty is associated with the length of
time reguired to reduce contaminants to below groundwater cleanup levels. The estimate of 27 years for
intrinsic bioremediation is based on very conservative assumptions as detailed in Appendix C. Should
ethylbenzene degrade as rapidly as the other organic CPCs, remedial objectives could be met within
approximately 10 years. This shorted treatment period would reduce O&M costs and total present worth
costs proportionally for all alternatives. Therefore, further sensitivity analysis to assess effects from
"across the board" remedial action time reduction was not performed for these alternatives.

However, it is noted that expenses incurred for Alternative 3 assume that oxygen releasing compounds and
nutrient application would be reguired for the entire 27-year remedial action time period. Numerous other
scenarios are egually likely (i.e., biodegradation within the plume area could occur to the extent that
the contaminant plume would shrink in size within five years and that maintenance of the bioremediation
wells would not be reguired for the remaining duration of 22 years that it would take to reduce CPCs
below PRGs). Reducing need for aerobic treatment time would significantly reduce O&M costs for
Alternative 3. The total present worth cost could be reduced to approximately 60 percent of the full
27-year total present worth cost (from approximately $1,140,000 to $680,000).

8. State Acceptance
This criterion addresses whether, based on its review of the RI, FS, and proposed plan, the state concurs
with, opposes, or has no comment on the alternative the Army is proposing as the remedy for both AOC 43G
and 43J. The Commonwealth of Massachusetts has reviewed the RI, FS, proposed plan, and this Record of
Decision and concurs with the selected remedy.

9_. Community Acceptance

The selected remedy to address groundwater contamination at AOC 43G is Alternative 2A. The selected
remedy to address groundwater contamination at AOC 43J is Alternative 2. Each of these alternatives
includes components for the monitoring of contaminant degradation and management of contaminant
migration. The remedial components of the selected remedy are described in detail below.

A. Groundwater Cleanup Levels

The PRGs for AOC 43G and 43J were developed in the FS following the USEPA guidance documents entitled,
Risk Assessment Guidance for Superfund: Volume 1 - Human Health Evaluation Manual (Part B, Development of
Risk Based Preliminary Remediation Goals), Interim, December 1991, and OSWER Directive 9355.0-30, Role of
the Baseline Risk Assessment in Superfund Remedy Selection Decisions. The PRGs will be used in the Record
of Decision as groundwater cleanup levels, and will be referred to as such in the remainder of this
Record of Decision. The first step in developing groundwater cleanup levels for protection of human
health was to identify those environmental media that in the baseline risk assessment presented either a
cumulative current or future cancer risk greater than 1x10 -4 or a cumulative noncarcinogenic HI greater
than 1, based on reasonable maximum exposure assumptions. The next step was to identify CPCs within the
media presenting cancer risks greater than 1x10 -6 or a HQ greater than 1.

1. AOC 43G

A comparison of detected concentrations of CPCs in source area and downgradient groundwater, to federal
and state drinking water standards showed several exceedances. In source area groundwater, the following
CPCs were detected at concentrations above a federal or state standard: xylenes, benzene, ethylbenzene,
arsenic, lead, nickel, aluminum, iron, manganese, and sodium. In downgradient groundwater, detected
concentrations of benzene, aluminum, iron, manganese, and sodium exceed federal or state drinking water
standards or guidelines.

At AOC 43G estimated noncarcinogenic risks exceeded the USEPA target level of 1 for both source area and
downgradient unfiltered groundwater at mean and maximum concentrations. His for the source area are 36
and 98 for exposure to mean and maximum concentrations, respectively. Benzene, manganese, iron, and
arsenic are the primary risk contributors for source area groundwater. His for downgradient groundwater
are 11 and 21 for mean and maximum concentrations, respectively. Manganese and benzene are the primary
contributors for downgradient groundwater. Individual HQs for the primary contributors in both source
area and downgradient groundwater all exceed the USEPA target level of 1.

For filtered groundwater, estimated noncarcinogenic risks exceeded the USEPA target level of 1 for both
source area and downgradient groundwater at mean and maximum concentrations. His for the source area are
36 and 98 for exposure to mean and maximum concentrations, respectively. Benzene, manganese, iron, and
arsenic are the primary contributors for source area groundwater. His for downgradient groundwater are 11
and 21 for mean and maximum concentrations, respectively. Manganese and benzene are the primary
contributors for downgradient groundwater. Individual HQs for the primary contributors in both source
area and downgradient groundwater all exceed the USEPA target level of 1. Based on this assessment,
source area PRGs were determined in the FS, for benzene (5 [micrograms per liter] Ig/L) , ethylbenzene
(700 I/L), xylenes (10,000,Ig/L), iron (9,100 Ig/L), manganese (291 I/L), and nickel (100 Ig/L). Arsenic
and lead were also found to exceed MCLs in source area groundwater, but these exceedances are directly
attributable to high levels of TSS in the samples. Because of this, respective PRGs were not developed.
PRGs were also established for downgradient groundwater and were limited to benzene (5 Ig/L) and
manganese (291 Ig/L). Lead was also detected, however, these exceedances appear to be attributable to
high TSS levels.

A complete discussion of the PRGs is presented in Section 2 of the AOC 43G FS report. Tables 4 and 5
summarize the groundwater cleanup levels for source area and downgradient groundwater at AOC 43G.

2. AOC 43J

In source area groundwater, at AOC 43J, the following CPCs were detected at concentrations above a
federal or state standard: benzene, ethylbenzene, toluene, carbon tetrachloride, chloroform, arsenic,
cadmium, lead, sodium, aluminum, iron, and manganese. In downgradient groundwater, detected
concentrations of benzene, chloroform, aluminum, iron, and manganese exceed federal or state drinking
water standards or guidelines.

For filtered groundwater, estimated noncarcinogenic risks exceeded the USEPA target level of 1 for both
source area and downgradient groundwater at mean and maximum concentrations. His for the source area are
24 and 52 for exposure to mean and maximum concentrations, respectively. Benzene and manganese are
primary contributors at mean concentrations, while benzene, manganese and arsenic are the primary
contributors for maximum concentrations of filtered source area groundwater. His for downgradient
groundwater are 2 and 6 for mean and maximum concentrations, respectively. Manganese is the only
contributor with an HQ exceeding 1. Based on this assessment, PRGs were determined in the FS for benzene
(5 Ig/L), carbon tetrachloride (5 Ig/L), ethylbenzene (700 Ig/L), toluene (1,000,Ig/L), arsenic (50
Ig/L) , iron (9,100 Ig/L), and manganese (291 Ig/L) in the FS report. Cadmium and lead were also found to
exceed MCLs in the source area and arsenic in downgradient groundwater. However, these exceedances are
directly attributable to high TSS in the samples. Because of this, respective PRG were not developed.
PRGs were also established for downgradient groundwater and were limited to benzene (5 Ig/L) and
manganese (291 Ig/L). Arsenic was also detected, however, these exceedances appear to be attributable to
high TSS levels.

A complete discussion of the PRGs is presented in Section 2 of the AOC 43G FS report. Tables 6 and 7
summarize the groundwater cleanup levels for source area and downgradient groundwater at AOC 43J.

B. Description of Remedial Components

1. AOC 43G

Alternative 2A: Intrinsic Bioremediation

Intrinsic bioremediation is the principal component in Alternative 2A that is proposed to prevent CPCs
that exceed groundwater cleanup levels from potentially migrating off Army property or an area located
sufficiently inside the boundary in which compliance will be determined, according to cleanup criteria
stated in the Record of Decision, that at minimum will meet drinking water standards. The installation of
additional monitoring wells and implementation of a long-term groundwater monitoring program, along with
annual reports, will enable assessment of the biodegradation progress, and permit detection of any
potential migration of contaminants beyond the Devens Reserve Forces Training Area boundary. In addition,
the Army will follow the "Technical Protocol for Implementing Intrinsic Remediation with Long-Term
Monitoring for Natural Attenuation of Fuel Contamination Dissolved in Groundwater," co-developed by the
USEPA and the U.S. Air Force Center for Environmental Excellence, dated November 11, 1995. Key components
of this alternative include:

• intrinsic bioremediation
• intrinsic bioremediation assessment data collection and groundwater modeling
• installing additional groundwater monitoring wells
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews

Each of these components is described in the following paragraphs.

Intrinsic Bioremediation. Based upon organic and inorganic speciation in the aguifer, it appears that
biological degradation of the petroleum hydrocarbons is naturally occurring at AOC 43G. Alternative 2A
would allow the natural biological degradation (intrinsic bioremediation) of the CPCs to continue at the
site without interruption. To assess the effectiveness of biological degradation at the site, groundwater
monitoring would be performed on a scheduled basis. Additional monitoring wells would be installed.

The biological degradation of hydrocarbons is essentially an oxidation-reduction reaction in which the
hydrocarbon compound is oxidized (donates electrons) and an electron acceptor, such as oxygen, is reduced
(accepts electrons). Under aerobic conditions, oxygen is the electron acceptor for biological degradation
activity. When oxygen is absent or depleted from a system, anaerobic conditions exist and other compounds
are used as electron acceptors. Other compounds that are used as electron acceptors during anaerobic
degradation of petroleum hydrocarbons include nitrate, manganese oxides, sulfate, iron, and hydrogen.

The electron acceptor that is ultimately used in the anaerobic biodegradation of hydrocarbons depends
upon compound concentrations, availability, and the oxidation reduction potential of the aguifer.
According to free energy laws, the order in which electron acceptors are used in anaerobic biodegradation
-------
is as follows: oxygen (aerobic conditions), nitrate, manganese oxides, ferric iron (Felll), sulfate, and
hydrogen (methanogenic conditions). As the progression of electron acceptor use occurs through this
seguence, the oxidation reduction potential (ORP) of the aguifer decreases.

As defined by name, compounds that act as electron acceptors in anaerobic biodegradation gain electrons
and are reduced. Typical examples of reduced forms of compounds that are produced during anaerobic
biodegradation of hydrocarbons include nitrite from nitrate, manganese as Mn[II] from Mn[IV], ferrous
(Fe[II]) iron from ferric ([Fe(III)]) iron, sulfide compounds from sulfate reduction, and methane from
hydrogen reduction. The presence of these reduced forms of compounds in an aguifer is an indicator that
biological activity is occurring. Inorganic speciation can be used to model anaerobic biological
degradation.

Intrinsic bioremediation would continue at AOC 43G until the remedial action objectives are achieved.
Calculations based upon degradation rates from literature indicate that contaminants would not migrate
off Army property. Details of these calculations are discussed in Section 4 of the FS report. Additional
data collection would be reguired as part of the intrinsic bioremediation assessment to confirm
degradation rates, performance standards, and refine long-term groundwater monitoring needs.

Solute transport calculations were conducted for the site to provide further basis for evaluating
intrinsic bioremediation (see Appendix C of the Final FS report).

Intrinsic Bioremediation Assessment Data Collection and Groundwater Modeling. Prior to installation of
additional groundwater monitoring wells and refinement of a long-term groundwater monitoring plan,
additional data collection and modeling is reguired. A work plan will be prepared detailing the proposed
activities of the intrinsic bioremediation assessment, and will be submitted to the USEPA and MADEP for
review prior to implementation. The additional data collection will consist of supplemental soil sampling
and free product assessment in bedrock below the former gasoline USTs, additional round of groundwater
sampling and analysis to refine estimates of intrinsic bioremediation effectiveness in protecting
downgradient receptors. Collected data would include groundwater elevation, intrinsic bioremediation
indicators, and CPC concentrations. Groundwater elevation data would supplement the existing Fort Devens
water level data base for this site and would be used to refine groundwater flow direction. Intrinsic
bioremediation indicator data (e.g., electron acceptor concentrations, nutrient concentrations, and ORP)
will be used to verify occurring intrinsic bioremediation and determine future intrinsic bioremediation
potential. Table 8 in Appendix B outlines the proposed list of analytical parameters. CPC concentration
data will assist directly in estimating site-specific degradation rates and the effectiveness of
intrinsic bioremediation in achieving groundwater cleanup levels. Procedures, reguirements, and
analytical parameters for evaluation of CPCs and TPHC (using MADEP's volatile petroleum hydrocarbon [VPH]
and extractable petroleum hydrocarbon [EPH] methods), will be determined in the Intrinsic Bioremediation
Assessment Work Plan. Criteria for contaminant evaluations will use risk-based concentrations, MCLs
and/or MMCLs.

Data collected from the intrinsic bioremediation assessment groundwater sampling will be incorporated
into fate and transport modeling. This modeling will assess the degradation and migration of the organic
CPCs and refine current estimates of intrinsic bioremediation effectiveness. With intrinsic
bioremediation modeling will be conducted as part of the alternative long-term monitoring. The existing
and the new groundwater information will be examined to determine the best location for additional
groundwater monitoring wells and to finalize site-specific indicator data as reguired for the long-term
monitoring program. As additional monitoring data are collected during long-term monitoring (see
Long-Term Groundwater Monitoring in this subsection) , the fate and transport modeling will be updated to
allow the most accurate depiction of current and future groundwater conditions. The fate and transport
model used for monitoring intrinsic bioremediation (such as Bioplume II or III) will be selected based
upon the type of groundwater monitoring information gathered and market availability. Details of the
model will be Proposed as part of the intrinsic bioremediation assessment work plan.

Installing Additional Groundwater Monitoring Well Installation. Additional groundwater monitoring wells
will be reguired to improve data collection coverage in the overburden and bedrock within and
downgradient of the AOC. The ultimate number and location of additional groundwater monitoring wells for
monitoring intrinsic bioremediation at the site will depend upon the fate and transport modeling results.
These monitoring wells would be used to monitor contaminant plume location and concentration on Army
property in the overburden and bedrock and to collect intrinsic biodegradation indicators. Final
monitoring well locations and details will be submitted for regulatory review and concurrence.

Long-term Groundwater Monitoring. Long-term groundwater monitoring is proposed to enable assessment of
the intrinsic bioremediation progress and permit detection of any potential migration of contaminants
that exceed groundwater cleanup levels beyond Army property. Analytical parameters likely to be included
in the monitoring program are presented in Table 8 of Appendix B. Dependent upon the results of the fate
and transport modeling, groundwater monitoring would be conducted on an annual basis until three
-------
consecutive sampling rounds indicate that cleanup objectives have been met. The last two years of
monitoring (confirmation) would be for only the CPCs.

Annual Data Reports. Annual reports would be submitted to USEPA and MADEP which would include a
description of site activities, a summary of the long-term groundwater monitoring program results, and
any modeling updates. The final detailed Long-term Groundwater Monitoring Plan shall include performance
standard that will determine the effectiveness of the remedial action. The final detailed Long-Term
Groundwater Monitoring Plan would be developed in conjunction with regulatory agency review and comment.

Five-year Site Reviews. Under CERCLA 121(c) , any remedial action that results in contaminants remaining
on site must be reviewed at least every five years. During five year reviews, an assessment is made of
whether the implemented remedy continues to be protective of human health and the environment or whether
the implementation of additional remedial action is appropriate.

The five-year site review for Alternative 2A will evaluate the alternative's effectiveness at reducing
potential human health risk from exposure to groundwater on-site and downgradient considering current and
potential future receptors. This evaluation will be based on how successful the alternative is at
attaining groundwater cleanup levels at the long-term monitoring wells.

Specific criteria for evaluating the alternative's progress and effectiveness will be established upon
completion of the intrinsic bioremediation assessment data collection and groundwater modeling to permit
refinement of contaminant transport and biodegradation-estimates. The criteria and/or performance
standard will be contained in Long-term Monitoring Plan as developed in the remedial design/remedial
action Work Plan.

If the data generated from the modeling or the long-term groundwater monitoring efforts indicate that
groundwater cleanup cannot be met within 30 years, a more aggressive remedial action will take place to
enhance the intrinsic bioremediation alternative.

2. AOC 43J

Alternative 2: Intrinsic Bioremediation

Intrinsic bioremediation is the principal component in Alternative 2 that is proposed to reduce
contaminants on Army property at AOC 43J to below groundwater cleanup goals and also to prevent potential
migration of contaminants above groundwater cleanup goals off Army property. The installation of
additional monitoring wells and implementation of a long-term groundwater monitoring program will enable
assessment of the biodegradation progress and permit detection of any potential migration of contaminants
beyond the Army boundary. In addition, the Army will follow the 'Technical Protocol for Implementing
Intrinsic Remediation with Long-Term Monitoring for Natural Attenuation of Fuel Contamination Dissolved
in Groundwater," co-developed by the USEPA and the U.S. Air Force Center for Environmental Excellence,
dated November 11, 1995. Key components of this alternative include:

Each of these components is described in the following paragraphs.

Intrinsic Bioremediation. A discussion of the intrinsic bioremediation process is covered in the
beginning of this subsection and will not be repeated here. Based upon organic and inorganic speciation
in the aguifer and other water guality parameters, it appears that degradation of the organic CPCs is
occurring naturally at AOC 43J. Solute transport calculations were conducted for the site to provide
further basis for evaluating intrinsic bioremediation (see Appendix D of the Final FS).

Intrinsic Bioremediation Assessment Data Collection and Groundwater Modeling. Prior to installation of
additional long-term groundwater monitoring wells and refinement of a long-term groundwater monitoring
plan, additional data collection and modeling is reguired. A work plan will be prepared detailing the
proposed intrinsic bioremediation assessment activities, and will be submitted to the USEPA and MADEP for
review prior to implementation. Data collection would likely consist of the installation of bedrock
wells, an additional round of groundwater sampling and analysis to refine estimates of intrinsic
bioremediation effectiveness in protecting downgradient receptors. Collected data would include
groundwater elevation, intrinsic bioremediation indicators, and concentrations for CPCs. Groundwater
elevation data would supplement the existing Fort Devens water level data base for this site and would be
-------
used to refine groundwater flow direction which appears to vary seasonally. Intrinsic bioremediation
indicator data (e.g., electron acceptor concentrations, nutrient concentrations, and oxidation-reduction
potential) will be used to provide additional evidence that intrinsic bioremediation is occurring and
determine future intrinsic bioremediation potential. Table 9 in Appendix B outlines the proposed list of
analytic parameters. CPC concentration data will assist directly in estimating site-specific degradation
rates and the effectiveness of intrinsic bioremediation in achieving groundwater cleanup goals.
Procedures, reguirements, and analytical parameters for evaluation of CPCs and TPHC (using MADEP's
VPH/EPH method), will be determined in the Intrinsic Bioremediation Assessment Work Plan. Criteria for
contaminant evaluation will use risk-based concentrations, MCLs, and/or MMCLs.

Data collected from the intrinsic bioremediation assessment groundwater sampling will be incorporated
into fate and transport modeling. This modeling will assess the degradation and migration of the organic
CPCs and refine current estimates of intrinsic bioremediation effectiveness. Initial intrinsic
bioremediation modeling will be conducted as part of the alternative long-term monitoring phase. The
existing and the new groundwater information will be examined to determine the best location for
additional groundwater monitoring wells and to finalize site-specific indicator data as reguired for the
long-term monitoring program. As additional monitoring data are collected during long-term monitoring
(see Long-Term Groundwater Monitoring in this subsection) , the fate and transport modeling will be
updated to allow the most accurate depiction of current and future groundwater conditions. The fate and
transport model used for monitoring intrinsic bioremediation (such as Bioplume II) will be selected based
upon the type of groundwater monitoring information gathered and market availability. Details of the
model will be proposed as part of the intrinsic bioremediation assessment work plan.

Installing Additional Groundwater Monitoring Well Installation. Additional groundwater monitoring wells
will be reguired to improve data collection coverage within the source area and downgradient of the site.
The ultimate number and location of additional long term groundwater monitoring wells will depend upon
results of the fate and transport modeling. These wells would be used to monitor contaminant plume
location and concentration in relation to the Army boundary and to collect intrinsic biodegradation
indicators. Final monitoring well locations and details will be submitted for regulatory review and
concurrence in the Long-Term Groundwater Monitoring Plan.

Long-term Groundwater Monitoring. Long-term groundwater monitoring is proposed to enable assessment of
the intrinsic bioremediation progress and permit detection of any potential migration of contaminants
that exceed groundwater cleanup levels beyond Army property. Analytical parameters likely to be included
in the monitoring program are presented in Table 9 in Appendix B. Dependent upon the results of the fate
and transport modeling, groundwater monitoring would be conducted on an annual basis until three
consecutive sampling rounds indicate that cleanup objectives have been met. It is estimated to take 27
years to achieve cleanup objectives plus two additional yearly sampling rounds for a total of 29 years of
groundwater monitoring. The last 2 years of monitoring (confirmation) would be for only the CPCs.

Annual Data Reports. Annual reports would be submitted to USEPA and MADEP which would include a
description of site activities, a summary of the long-term groundwater monitoring program results, and
any modeling updates. The final detailed Long-term Groundwater Monitoring Plan shall include performance
standards that will determine the effectiveness of the remedial action. The final detailed Long-Term
Groundwater Monitoring Plan would be developed in conjunction with regulatory agency review and comment.

Five-year Site Reviews. Under CERCLA 121(c), any remedial action that results in contaminants remaining
on-site must be reviewed at least every five years. During five year reviews, an assessment will be made
of whether the implemented remedy will continue to be protective of human health and the environment, or
whether the implementation of additional remedial action is appropriate.

The five-year review for Alternative 2 will evaluate the alternative's effectiveness at reducing
potential human health risk from exposure to groundwater on-site and downgradient considering current and
potential future receptors. This evaluation will be based on how successful the alternative is at
attaining groundwater cleanup levels at the long-term monitoring wells.

Specific criteria for evaluating the alternative's progress and effectiveness will be established upon
completion of the intrinsic bioremediation assessment data collection and groundwater modeling to permit
refinement of contaminant transport and biodegradation estimated. The criteria and/or performance
standard will be contained in the Long-term Monitoring Plan as developed in the remedial design/remedial
action Work Plan.

If the data generated from the modeling or the long-term groundwater monitoring efforts indicate that
groundwater, cleanup cannot be met within 30 years, a more aggressive remedial action will take place to
enhance the intrinsic bioremediation alternative.
-------
XI. STATUTORY DETERMINATIONS

The selected remedy for AOC 43G and 43J groundwater, Alternative 2A and Alternative 2, respectively, is
consistent with CERCLA and, to the extent practicable, the NCP. The selected remedy is protective of
human health and the environment, attains ARARs, and is cost-effective. The remedy utilizes permanent
solutions and alternative treatment technologies, to the maximum extent practicable for this site.

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

The alternative chosen for AOC 43G and 43J will permanently reduce the risks to human health and
environment by eliminating, reducing, or controlling exposures to human and environmental receptors
through engineering and institutional controls. The principal threat at AOC 43G and 43J is potential
commercial/industrial use of contaminated groundwater. The reuse of these portions of Devens as part of
the Reserve Forces Training Area would prevent the use of groundwater from the contaminated aguifer,
resulting in reduced potential for commercial/industrial human exposure to contaminated groundwater. The
continued Army maintenance activities will help ensure protection of human health and the environment by
maintaining the integrity of existing pavement and ground cover.

Groundwater modeling done during the FS suggests that the groundwater contaminant plumes at each AOC will
not migrate off Army property or an area located sufficiently inside the boundary in which compliance
will be determined, according to cleanup criteria stated in the Record of Decision, that at minimum will
meet drinking water standards. However, if at anytime during the implementation of this alternative the
following occurs:

• Based on post Record of Decision fate and transport modeling, the time frame for
degradation/remediation of the existing groundwater contaminant plume to groundwater cleanup
levels, is determined to be longer then 30 years,

• performance standards (outlined in the Long-Term Monitoring Plan) are not achieved,

• groundwater sampling results or fate and transport modeling show the existing groundwater
contaminant plume will migrate off Army property above groundwater cleanup levels, MCLs, or
MMCLs,

• the five-year site review indicates that the intrinsic bioremediation alternative is not
protective of human health.

The Army will evaluate an appropriate remedial action to protect human health and the environment as
reguired under CERCLA.

B. The Selected Remedy Attains ARARs.

The selected remedy will attain all applicable or relevant and appropriate federal and State
reguirements. No waivers are reguired. ARARs for the selected remedial alternative for both AOC 43G and
43J were identified and discussed in the Final FS (Sections 2 and 5). Environmental laws from which ARARs
for the selected remedial action are derived, and specific ARARs are summarized in Tables 10 through 12
in Appendix B.

C. The Selected Remedy is Cost-Effective.

In the Army's judgment, the selected remedies are cost effective (i.e., the remedies afford overall
effectiveness proportional to costs). In selecting these remedies, once the Army identified alternatives
that are protective of human health and the environment and that attain ARARs; the Army evaluated the
overall effectiveness of each alternative according to the relevant three criteria -- long-term
effectiveness and permanence; reduction in toxicity, mobility, and volume through treatment; and
short-term effectiveness, in combination. The relationship of the overall effectiveness of these remedial
alternatives was determined to be proportional to costs.

Review of the discussion of "Overall Protection of Human Health and the Environment" in Subsection IX.A.
and of "Cost" in Subsection IX.G. suggests that each of the other alternatives assessed in each FS all
provide a similar level of protectiveness. However, Alternative 2A for AOC 43G and Alternative 2 for AOC
43J, do so at the lowest cost and are considered the most cost-effective. The costs of the selected
remedy, Alternative 2A for AOC 43G, in 1996 dollars are:
-------
Estimated Time or Restoration: Approximately 12 months for engineering
evaluations, design, and construction.
Estimated Capital Cost: $ 39,000
Estimated Operation and Maintenance Cost:
(net present worth) $406,300
Estimated Total Cost: (net present worth,
assuming 5% discount rate) $445,300

The costs of the selected remedy, Alternative 2 for AOC 43J, in 1996 dollars are:

Estimated Time for Restoration: Approximately 12 months for engineering
evaluations, design, and construction.
Estimated Capital Cost: $ 47,200
Estimated Operation and Maintenance Cost:
(net present worth) $394,500
Estimated Total Cost: (net present worth,
assuming 5% discount rate) $441,700

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

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

a. AOC 43G

Alternative 1 is considered egual to Alternative 2A when comparison is made to threshold criteria except
that Alternative 1 compliance would not be able to be monitored. Alternative 1 is similar to Alternative
2A when considering primary balancing criteria except that there would be no effects to site-workers
during remedy implementation or cost associated with implementation of Alternative 1. (There is no active
remedial action or monitoring implemented in Alternative 1.)

Alternative 2A is similar to Alternatives 2B, 3, and 4 when considering threshold criteria, in that they
all are protective of human health and are expected to meet ARARs. Alternative 2B uses SVE to minimize
the potential for groundwater recontamination thereby improving the probability that intrinsic
biodegradation can achieve PRGs. However, if gross contamination exists within the bedrock fractures,
removal of residual soil contamination below the former gasoline USTs with SVE may not improve
groundwater remediation significantly. Alternatives 3 and 4 use backup components to achieve groundwater
cleanup levels if intrinsic biodegradation does not perform as anticipated. Alternative 2A would rely on
additional data collection, modeling, long-term groundwater monitoring, five-year site reviews, and
contingency actions (Alternative 2B) for additional action to ensure that intrinsic bioremediation is
protective of human health and the environment. The added treatment technologies in Alternatives 2B, 3,
and 4 can be interpreted as increasing the potential protection of downgradient receptors, although each
could be added as contingency alternatives to Alternative 2A upon nonperformance of intrinsic
biodegradation without jeopardizing overall protection of human health and the environment.

In general, Alternative 2A is also similar to Alternatives 2B, 3, and when 4 considering primary
balancing criteria (but less expensive). Alternatives 2B, 3, and 4 more favorably offer supplemental or
back-up treatment processes which contribute to the reduction of toxicity, mobility, and volume of
contaminants. However, intrinsic biodegradation is likely to be the controlling factor in determining the
time reguired for remedial action. The back-up treatment processes in Alternatives 2B, 3, and 4 would
generate concentrated waste streams (sludge, filtered material, and spent carbon) that would reguire
disposal. Because of more intrusive activities, monitoring reguirements, and construction work, the
potential for contaminant exposure and safety hazards to workers increases with Alternatives 2A, 2B, 3,
and 4, in order presented. The engineering complexity also increases for Alternatives 2A, 2B, 3, and 4,
in order presented.
-------
Alternatives 2A through 4 all require additional data collection, modeling, or pumping tests prior to
design and implementation. Alternative 2A is the least expensive alternative followed by Alternatives 2B,
3, and 4.

Alternative 3 is considered egual to Alternative 4 when considering threshold criteria, in that they both
are protective of human health and will meet ARARs. Alternatives 3 and 4 use active redundant or backup
treatment components to stop CPCs that exceed groundwater cleanup levels from migrating off Army
property. Alternative 3 utilizes groundwater collection and-treatment to intercept the more highly
contaminated portion of the plume, therefore protecting human health and the environment downgradient of
Army property. Alternative 4 utilizes both groundwater collection/treatment and passive aerobic
bioremediation to ensure protection of human health downgradient of Army property. The added active
treatment technologies in Alternative 4 can be interpreted as increasing the potential protection for
downgradient receptors, although passive bioremediation could be added as a contingency alternative to
Alternative 3 upon nonperformance of groundwater extraction and intrinsic biodegradation without
jeopardizing overall protection of human health and the environment. Alternative 3 might also be
considered equal to Alternative 4 when considering primary balancing criteria for reasons similar to
those specified for Alternative 2A

b. AOC 43J

Alternative 1 is considered equal to Alternative 2 when considering threshold criteria, except that
compliance would not be able to be monitored. Alternative 1 is also considered equal to Alternative 2
when considering primary balancing criteria, except that there would be no effects to site-workers during
remedial implementation or cost associated with implementation of Alternative 1. (There is no active
remedial action or monitoring implemented in Alternative 1.)

Alternative 2 is considered equal to Alternatives 3, 4 and 5 when considering threshold criteria, in that
they all are protective of human health and meet ARARs. Alternatives 3, 4, and 5 use redundant or backup
components to achieve groundwater cleanup levels. Alternative 2 would rely on additional data collection,
modeling, long-term groundwater monitoring, five-year site reviews, and contingencies for additional
action to ensure that intrinsic bioremediation is protective of human health and the environment. The
added treatment technologies in Alternatives 3, 4, and 5 can be interpreted as increasing the protection
of downgradient receptors, although each could also be added as contingency alternatives to Alternative 2
upon nonperformance of intrinsic biodegradation without jeopardizing overall protection of human health
and the environment.

In general, Alternative 2 is also equal to or better than Alternatives 3, 4, and 5 when considering
primary balancing criteria. Alternatives 3, 4 and 5 more favorably offer back-up treatment processes
which contribute to the reduction of toxicity, mobility, and volume of contaminants, although intrinsic
biodegradation is considered to be the controlling factor in determining the time required for remedial
action. The back-up treatments in Alternatives 4 and 5 would generate concentrated waste streams (i.e.,
sludge, filtered material, spent carbon) that would require disposal. Also, the potential for groundwater
re-contamination exists when the groundwater table rebounds after groundwater extraction has been halted
for Alternatives 4 and 5. Because of more intrusive activities, monitoring requirements and construction
work, the potential for contaminant exposure and safety hazards to workers increases with Alternatives 2,
3, 4 and 5, in order presented. Alternative 2 is expected to take the same number of years for
remediation as Alternatives 3 and 5 (27 years) and take a shorter time than Alternative 4 (36 years). The
engineering complexity increases for each alternative (i.e., Alternative 5 > Alternative 4 > Alterative 3
> Alternative 2). Alternatives 2 through 5 all require additional data collection, modeling or pilot
testing prior to design and implementation. Alternatives 2 is the least expensive alternative followed by
Alternatives 3, 4, and 5, in order of increasing cost.

Alternative 3 is considered equal to Alternatives 4 and 5 when comparing threshold criteria in that they
all are protective of human health and meet ARARs. Alternatives 4 and 5 use active redundant or backup
treatment components to achieve groundwater cleanup levels if intrinsic biodegradation does not perform
as anticipated. Alternative 3 utilizes passive aerobic bioremediation to ensure protection of human
health and the environment downgradient of Army property. The added active treatment technologies in
Alternatives 4 and 5 can be interpreted as increasing the potential protectiveness for downgradient
receptors, although each could also be added as contingency alternatives to Alternative 3 upon
nonperformance of intrinsic biodegradation without jeopardizing overall protection of human health and
the environment. Alternative 3 is also equal to or better than Alternatives 4 and 5 when considering
primary balancing criteria for reasons similar to those specified for Alternative 2.

Alternative 4 is considered equal to Alternative 5 when considering threshold criteria, in that they are
both protective of human health and meet ARARs. Alternatives 4 and 5 both use active redundant or backup
treatment components to achieve groundwater cleanup levels if intrinsic biodegradation does not perform
as anticipated. Alternative 5 uses an active treatment, SVE, to minimize potential groundwater
-------
re-contamination upon aquifer rebound following completion of groundwater extraction. The active
treatment technology in Alternatives 5 can be interpreted as increasing the potential protectiveness for
downgradient receptors. However, both alternatives require soil monitoring to assess groundwater
re-contamination potential which could be difficult to perform because of the heterogenous soil medium
and contaminant distribution.

Alternative 4 is also considered essentially equal to Alternatives 5 when considering primary balancing
criteria. Alternative 5 more favorably uses the back-up soil treatment process, SVE, which contributes to
the reduction of toxicity, mobility, and volume of contaminants within a shorter time than Alternative 4.
However, additional pilot testing is required for Alternative 5. Because of more intrusive activities,
monitoring requirements and construction work, the potential for contaminant exposure and safety hazards
to workers is greater for Alternative 5. Also the total present worth cost is greater for Alternative 5
than for Alternative 4.

XII. DOCUMENTATION OF NO SIGNIFICANT CHANGES

The Army presented a proposed plan (preferred alternative) for remediation of groundwater contamination
at AOC 43G and 43J at a public meeting held on September 5, 1996. The components of the preferred
alternative (at AOC 43G, Alternative 2A: Intrinsic Bioremediation, and at AOC 43J, Alternative 2:
Intrinsic Bioremediation)included:

No changes or additions have been made to either alternative since the publication of the proposed plan.

XIII. STATE ROIiE

The Commonwealth of Massachusetts has reviewed the alternatives presented in each FS and proposed plan
and concurs with the selected remedy for the cleanup of the groundwater contamination at AOC 43G and 43J.
The Commonwealth has also reviewed the RI and FS to determine if the selected remedy complies with
applicable or relevant and appropriate laws and regulations of the Commonwealth. A copy of the
declaration of concurrence is attached as Appendix E.
-------
APPENDIX A - FIGURES

-------
APPENDIX B - TABIiES
TABLE 1
SUMMARY OF SUBSURFACE STATISTICS
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION
AREA 2 SUBSURFACE SOIL (1 -

PAL METALS
Aluminum
Arsenic
Barium
Beryllium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Nickel
Potassium
Sodium
Vanadium
Zinc

Range of
SOLs
15 feet bgs)
N/A
N/A
N/A
0.5 - 0
N/A
N/A
1.42 - 1
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Freguency
of
Detection
a (mg/kg)
5/5
5/5
5/5
.5 4/5 0
5/5
5/5
.42 4/5
5/5
5/5
5/5
5/5
5/5
5/5
5/5
5/5
5/5
5/5
De
Conce
Minimu

3770
7.15
21.5
.964
651
8.89
1.67
6.54
9460
3.58
1590
81.7
6.08
702
267
11.6
18.2
RECORD OF DECISION
FORT DEVENS, MA
Detected
id
ions
ximum
12200
21
66.5
1.38
2000
37.4
9.94
14.4
15300
50
5670
324
33.4
4290
330
26.3
208
Mean
of all
Samples
6788
12.1
38.0
0.9
1073.6
23.8
4.9
10.2
12292
14.1
3488
177.8
17.4
2086.4
295.6
18.1
63.5

Back-
Ground CPC?
18000
19
54
0.81
810
33
4.7
13.5
18000
48
5500
380
14.6
2400
234
32.3
43.9

Nc
No
Yes
Yes
Yes
No
Yes
Yes
Yes
No
Yes
No
No
Yes
No
No
No
Yes
Background 1
Essential Nutrient 2
Background 1
Toxicity Value 3
Essential Nutrient 2
Background 1

Essential Nutrient 2
Essential Nutrient 2
Background 1
-------
PAL SEMIVOLATILE ORGANICS
Acenaphthylene
Anthracene
Benzo[a]Anthracene
Benzo[a]Pyrene
Benzo[b]Fluoranthene
Benzo[g,h,i]Perylene
Benzo[k]Fluoranthene
Chrysene
Di-n-butyL Phthalate
Fluoranthene
Fluorene
Indeno[1,2,3-c,d]Pyrene
Naphthalene
Phenanthrene
Pyrene
0.033 -
0.033 -
0.17 -
0.25 -
0.21 -
0.25 -
0.066 -
0.12 -
0.061 -
0.068 -
0.033 -
0.29 -
0.037 -
0.033 -
0.033 -
0.2
0.2
0.8
1
1
1
0.3
0.6
0.6
0.3
0.2
1
0.2
0.2
0.2
1/5
1/5
1/5
1/5
1/5
1/5
1/5
1/5
3/5
1/5
1/5
1/5
1/5
1/5
1/5
5
4
7
10
30
3
6
10
0.43
20
1
4
0.5
10
10
5
4
7
10
30
3
6
10
0.6
20
1
4
0.5
10
10
1.
0,
1.
2,
6,
0,
1.
2,
0,
4,
0,
1.
0,
2,
2,
.0
.8
.5
.2
.2
.8
.2
.1
.4
.1
.2
.0
.1
.0
.0
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No Blank 4
Yes
Yes
Yes
Yes
Yes
Yes
PAL VOLATILE ORGANICS
Acetone
Trichlorofluoromethane
0.017 -
0.006
0.017 1/5
0.006 3/5
0.047
0.0057
0.047
0.01
0.02
0.01
NDB No Blank 4
NDB No Blank 4
OTHER
Total Petroleum Hydrocarbon
28.5 - 28.8 2/5
158
185
77.2
NDB Yes Toxicity Value 3
-------
TABLE 1
SUMMARY OF SUBSURFACE STATISTICS
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION
AREA 2 SUBSURFACE SOIL (1 -

PAL METALS
Aluminum
Arsenic
Barium
Cadmium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Nickel
Potassium
Sodium
Vanadium
Zinc

PAL SEMIVOLATILE ORGANICS
2-Methylnaphthalene
Naphthalene

PAL VOLATILE ORGANICS
Toluene
Ethylbenzene
Xylenes
Freguency E
Range of of Cono
SOLs Detection Minim
- 15 feet bgs) a

0.7

1.42

0.049 - 0
0.037 - 0
0.001 - 0
0.002 0
0.002 0
3.006 - 0.
N/A
N/A
N/A
- 0.7
N/A
N/A
- 1.42
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
.5
.4
.001
.002
.002
006
(mg/kg)
4/4
4/4
4/4
1/4
4/4
4/4
1/4
4/4
4/4
4/4
4/4
4/4
4/4
4/4
4/4
4/4
4/4
1/4
1/4
1/4
1/4
1/4
1/4
5100
17
14.6
2.61
405
17.4
3.56
9.09
9660
5.12
2250
86.6
19.5
568
287
8.24
21.3
0.72
0.46
0.02
0.03
0.6
0.03
RECORD OF DECISION
FORT DEVENS, MA
Detected
d
_ons
Mean
of all

Back-
limum Samples Ground
11200
51
53.3
2.61
1570
46
9.93
29.2
19300
57
6100
267
38.3
1340
419
19.9
87.6
0.72
0.46
0.02
0.03
0.6
0.03
8835
31.8
30.2
0.9
1026.3
30.4
6.4
16.4
12665
21.8
3915.0
205.4
25.2
965.5
336
15.4
42.4
0.3
0.2
0.005
0.008
0.2
0.01
18000
19
54
1.28
810
33
4.7
13.5
18000
48
5500
380
14.6
2400
234
32.3
43.9
NDB
NDB
NDB
NDB
NDB
NDB

CPC? Notes
No Background 1
Yes
No Background 1
Yes
No Essential Nutrient
Yes
Yes
Yes
Yes
Yes
No Essential Nutrient
No Background 1
Yes
No Essential Nutrient
No Essential Nutrient
No Background 1
Yes
Yes
Yes
Yes
Yes
Yes
No Blank 4

2
2

OTHER
Total Petroleum Hvdrocarbons
N/A
4/4
59.2
1020
412.i
NDB Yes Toxicity Value 3
-------
TABLE 1
SUMMARY OF SUBSURFACE STATISTICS
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION

RECORD OF DECISION
FORT DEVENS, MA
Frequency
SOURCE AREA GROUNDWATER

PAL METALS
Aluminum
Arsenic
Barium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Nickel
Potassium
Sodium
Vanadium
Zinc

PAL SEMIVOLATILE ORGANICS
2,4-Dimethylphenol
2-Methylphthalene
4-Methylphenol/4-Cresol
Acenaphthene
Anthracene
Bis (2-ethylhexyl)Phthalate
Fluorene
Naphthalene
Phenanthrene

PAL VOLATILE ORGANICS
Xylenes
Benzene
Carbon Disulfide
Ethylbenzene
Methylene Chloride
Methyl isobutyl ketone
Toluene
Range of of
SOLs Detection
c (mg/L)
0.141 -
0.003 -
NA
NA
0.006 -
0.025 -
0.008 -
NA
0.001 -
NA
NA
0.034 -
NA
NA
0.011 -
0.021 -
:s
0.006 -
Concentrations
Minimum Maximum
of all Back-
Samples Ground CPC? Notes
- UNFILTERED
0.141
0.003

0.006
0.025
0.008

0.001

0.034

0.011
0.021
0.06
0.002 - 0.002
0.001 -
0.002 -
0.001 -
.ate NA
0.004 -
0.001 -
0.001 -
NA
NA
0.001 -
NA
0.002 -
0.003 -
0.001 - 0
0.005
0.02
0.005

0.004
0.001
0.001

0.1

0.6
0.8
.001
8/12
11/12
12/12
12/12
3/12
2/12
2/12
12/12
8/12
12/12
12/12
4/12
12/12
12/12
2/12
5/12
2/12
10/12
1/12
1/12
1/12
12/12
2/12
11/12
3/12
12/12
12/12
1/12
12/12
3/12
1/12
11/12
0.147
0.0033
0.0078
51.2
0.0069
0.034
0.0199
1.46
0.0017
8.84
2.88
0.0812
1.36
40.5
0.0122
0.0276
0.016
0.0021
0.0033
0.0032
0.0014
0.0045
0.02
0.0009
0.0006
0.0013
0.0021
0.0009
0.019
0.0027
0.019
0.0015
10.7
0.0577
0.0816
112
0.0292
0.046
0.0402
87.2
0.0491
29.6
14.3
0.209
7.82
99.6
0.0122
0.101
0.021
2
0.0033
0.0032
0.0014
0.2
0.04
1
0.02
20
2
0.0009
2
0.02
0.019
0.3
2.20
0.01
0.03
74.53
0.007
0.02
0.008
25.89
0.009
18.9
7.6
0.05
3.2
70.6
0.006
0.03
0.01
0.3
0.0007
0.002
0.005
0.05
0.007
0.2
0.003
3.36
0.62
0.01
0.43
0.04
0.06
0.09
6.87
0.0105
0.0396
14.7
0.0147
0.025
0.0081
9.1
0.0043
3.48
0.291
0.0343
2.37
10.8
0.011
0.0211
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
Yes
Yes
Yes
No Essenti
Yes
Yes
Yes
Yes
Yes
No Essenti
Yes
Yes
No Essenti
No Essenti
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No Blank 4
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No Blank 4
No Blank 4
Yes
-------
SOURCE AREA GROUNDWATER c (mg/L) - FILTERED
PAL METALS
Aluminum
Antimony
Arsenic
Barium
Calcium
Iron
Lead
Magnesium
Manganese
Nickel
Potassium
Sodium
0.
0.

141 - 0.141
003 - 0.003
NA
NA
NA
NA
.001 - 0.001
NA
NA
034 - 0.034
NA
NA
1/12
2/12
12/12
12/12
12/12
12/12
4/12
12/12
12/12
2/12
12/12
12/12
0.3
0.0028
0.0047
0.0081
53.1
2.19
0.0014
9.06
3.12
0.0651
1.41
42
0.3
0.004
0.024
0.0485
101
54.1
0.003
27.3
15.2
0.18
6.66
105
0.09
0.002
0.01
0.02
72.4
18.50
0.001
17.6
7.5
0.03
2.7
70.9
6.87
0.003
0.0105
0.0396
14.7
9.1
0.0043
3.48
0.291
0.0343
2.37
10.8
No
Yes
Yes
Yes
No
Yes
No
No
Yes
Yes
No
No
Background 1
Essential Nutrient 2

Background 1
Essential Nutrient 2
Essential Nutrient 2
Essential Nutrient 2
-------
TABLE 1
SUMMARY OF SUBSURFACE STATISTICS
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION

RECORD OF DECISION
FORT DEVENS, MA
Range of
SOLs

DOWNGRADIENT GROUNDWATER d (mg/L) - UNFILTERED
PAL METALS
Aluminum
Arsenic
Barium
Calcium
Iron
Lead
Magnesium
Manganese
Potassium
Sodium
Zinc

PAL SEMIVOLATILE ORGANICS
2-Methylnaphthalene
Bis (2-ethylhexyl)Phthalate
Naphthalene

PAL VOLATILE ORGANICS
Xylenes
Benzene
Ethylbenzene
Methylene Chloride
Tetrachloroethylene
Toluene
0.141 - 0.141
0.003 - 0.003
NA
NA
NA
0.001 - 0.001
NA
NA
NA
NA
0.021 - 0.021
0.002 - 0.002
0.005 - 0.005
0.001 - 0.001
0.001 - 0.001
0.001 - 0.001
0.001 - 0.001
0.002 - 0,002
0.002 - 0.002
0.001 - 0.001
Freguency
of
Detected
Concentrations
Detection
5/8
5/8
8/8
8/8
8/8
4/8
8/8
8/8
8/8
8/8
1/8
1/8
4/8
3/8
4/8
6/8
3/8
1/8
2/8
5/8
0
0.
0.

0.
0.
0.
0
0.
0.
0
0.
0.
0.
Minimum
.459
0107 0.
0131 0.
45.5
0.19
0018 0.
8.37
1.71
1.48
40.1
0249 0.
0022 0.
0046 0
.003 0.
0018 0
0015 0
.015 0
0022 0.
0033 0.
0005 0.
Maximum
1.86
0236
0276
64.7
12.4
0035
13.6
8.63
3.79
104
0249
0022
.064
0062
.047
.079
.029
0022
0038
0044
Mean
of all
Samples
0.7
0.01
0.02
55.2
5.6
0.002
10.5
5.2
2.6
60.6
0.01
0.001
0.02
0.002
0.01
0.02
0.008
0.001
0.001
0.002

Back-
Ground
6.87
0.0105
0.0396
14.7
9.1
0.0043
3.48
0.291
2.37
10.8
0.0211
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB

CPC?
No
Yes
No
No
Yes
No
No
Yes
No
No
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Yes

Notes
Background 5

Background 5
Essential Nutrient 2

Essential Nutrient 2
Essential Nutrient 2

Blank 4

-------
DOWNGRADIIENT GROUNDWATER d (mg/L) - FILTERED
PAL METALS
Arsenic
Barium
Calcium
Iron
Magnesium
Manganese
Potassium
Sodium
Zinc
0.003 - 0.003
NA
NA
NA
NA
NA
NA
NA
0.021 - 0.021
5/8
8/8
8/8
8/8
8/8
8/8
8/8
8/8
1/8
0.
0.

0.
,0078
,0117
44.2
,0602
8.09
1.86
1.44
39.3
,0689
0
0

0
.0141
.0237
66
9.84
12.8
8.82
2.91
110
.0689
0.007
0.02
55.6
2.9
10.2
5.3
2.3
61.6
0.02
0.0105
0.0396
14.7
9.1
3.48
0.291
2.37
10.8
0.0211
Yes
No
No
Yes
No
Yes
No
No
Yes
Background 1
Essential Nutrient 2

Essential Nutrient 2

Essential Nutrient 2
Essential Nutrient 2
NOTES
a Based on samples XGB-93-05X, XGB-93-06K, and XGB-93-07X
b Based on samples XGB-93-03X and XGB-94-04X
c Based on samples XGM-94-03X to -04X, XGM-93-02X AAFES-ID, -2, -6
d Based on samples XGM-94-06X to -08X, -10X

Background 1 - Sample concentrations detected are below background concentrations.
Essential Nutrient - Analyte is an essential human nutrient (magnesium, calcium, potassium, sodium) and is not considered a CPC.
Toxicity Value 3 - Compound cannot be evaluated guantitatively because toxicity values are not available.
Blank 4 - Compound was detected in field and/or laboratory blanks.
Background 5 - Maximum detected concentration of analyte was less than site-specific background concentrations.
SQL - Sample Quantitation Limit
NDB - not detected in background
N/A - not applicable
mg - milligram
L - liter
kg - kilogram
bgs - below ground surface
CPC - chemical of potential concern
-------
TABIiE 2
SUMMARY OF SEDIMENT STATISTICS
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION

RECORD OF DECISION
FORT DEVENS, MA
SEMIVOLATILE ORGANIC COMPOUNDS

bis (2-Ethylhexyl)phthalate
Di-n-butylhthalate
Acenaphthalene
Fluoranthene
Phenanthene
Pyrene

INORGANICS (mg/kg)
Aluminum
Arsenic
Barium
Beryllium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Nickel
Potassium
Sodium
Vanadium
Zinc

OTHER (mg/kg)
Total Petroleum Hydrocarbons
Frequency Detected
of Concentrations 1
Detection Minimum Maximum
(mg/kg)
1/2
1/2
1/2
1/2
^L
"2
2/2
2/2
2/2
^>
2/2
2/2
2/2
2/2
2/2
2/2
2/2
2/2
2/2
2/2
2/2
2/2
2/2

3
2.6
0.097
0.28
0.3
0.39
3710
3.77
17.2
0.621
1470
13.3
2.63
15.3
11400
24
1840
119
9.87
697
113
9.84
70.7

3
2.6
0.097
0.28
0.3
0.39
8370
7.5
32.2
0.621
1610
30.2
4.34
30.1
17200
99
3280
237
18.5
1430
298
25.3
136
Region III MCP
Back- Maximum Industrial S-2 Maximum
Ground Exceeds Soil Soil Exceeds
Cone. 2 Background? Cone. 3 Cone. 4 Guidelines?

NDB
NDB
NDB
NDB
NDB
NDB
10500
26
26.2
0.5
1100
15.9
7.2
14.3
7900
12.5
3100
600
18.6
292
289
13.3
55.6

_
-
-
-
-
—
NO
No
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
No
Yes
Yes
Yes
Yes

410
200000
ND
82000
ND
61000
1E-06
3.3
140000
1.3
ND
10000
120000
76000
ND
ND
ND
10000
41000
ND
ND
14000
610000

100
ND
100
600
100
500
ND
30
2500
0.8
ND
600
ND
ND
ND
600
ND
ND
700
ND
ND
2000
2500

No
No
No
No
No
No
No
Yes 5
No
No
-
No
No
No
-
No
-
No
No
-
No
No
No
2/2
448
1200
NDB
ND 2500
No
1 Based on sample XGD-93-02X from the SSI and sample SSD-93-39A from the AREE 70 Report
2 Sediment background values were extracted from Appendix K of Remedial Investigations Report
Functional Area II Volume IV of IV Appendices, prepared by Ecology and Environment, Inc., (1994)
3 Industrial soil concentrations developed in USEPA Region III Risk-Based Concentration Table (USEPA. 1995b).
4 The lowest of the MCP Method I S-2/GW-1, S-2/GW-2, and S-2/GW-3 soil standards.
5 Maximum concentration exceed Region III Industrial Soil Concentration
Cone. = concentration
- = not applicable
-------
TABIiE 3
SUMMARY OF SUBSURFACE SOIL STATISTICS
AOC 43J - HISTORIC GAS STATION J
RECORD OF DECISION
FORT DEVENS, MA
SOURCE AREA SUBSURFACE SOIL

PAL METALS
Aluminum
Antimony
Arsenic
Barium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Nickel
Potassium
Sodium
Vanadium
Zinc

PAL SEMIVOLATILE ORGANICS
2-Methylnaphthalene
bis (2-Ethyhexyl)phthalate
Di-n-butyl Phthalate
Naphthalene
Phenanthrenee
Pyrene

PAL VOLATILE ORGANICS
Xylenes
Acetone
Chloroform
Ethylbenzene
Toluene
Trichlorofluoromethane
Range of
SOLs
(1 -

Freguency
of
Detection
Detected Mean
Concentrations of all Back-
Minimum Maximum Samples Ground CPC? 1
15 feet bgs) a (mg/kg)
N/A
1.09 - 1.
N/A
N/A
N/A
N/A
1.42 - 1
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0.049 - 0
9/9
09 2/9
9/9
9/9
9/9
9/9
.42 9/9
9/9
9/9
10/10
9/9
9/9
9/9
9/9
9/9
9/9
9/9
.5 6/9
0.62 - 6 2/9
0.061 - 0.6 1/9

0.
0.
0,
0.
0.
0
0.037 - 0
0.033 - 0
0.033 - 0
0015 - 0.
017 - 8
.0009 - 0.
0017 - 0.
.4 5/9
.2 1/9
.2 1/9
0015 8/10
1/10
4 1/10
0017 7/10
0008 - 0-0008 5/10
.0059 - 3
1/10
3950
2.01
9.4
15.3
566
12.9
5.99
14.5
12900
6.7
1680
252
23.2
561
366
6.42
21.7
0.093
1
1.4
0.71
0.5
0.7
0.0063
0.044
0.0081
0.0042
0.1
0.0082
9500
3.28
20
28.7
1450
36
9.84
169
18000
86
4120
828
36.9
1180
485
20.6
99
7
2.8
1.4
10
0.5
0.7
100
0.044
0.0081
30
20
0.0082
7145.6
1.0
141
20.1
963.2
187
7.7
33.3
15877.8
18.0
3536.7
489.9
29.5
769.1
431.2
10.3
40.4
1.3
1.1
0.2
1.5
0.08
0.1
30
0.9
0.04
7.8
3.6
0.3
18000
0.5
19
54
810
33
4.7
13.5
18000
48
5500
380
14.6
2400
234
32.3
43.9
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB
No
Yes
Yes
No
No
Yes
Yes
Yes
No
Yes
No
Yes
Yes
No
No
No
Yes
Yes
No
No
Yes
Yes
Yes
Yes
No
No
Yes
Yes
No
Background 1
Background 1
Essential Nutrient 2
Background 1
Toxicity Value 3
Background 1, Essential Nutrient 2
Background 1, Essential Nutrient 2
Essential Nutrient 2
Background 1
Blank 4
Blank 4
Blank 4
Blank 4
Blank 4
OTHER
Total Petroleum Hydrocarbons
N/A
10/10
46.2
1880
519.2
NDB
Yes Toxicity Value 3
-------
PERIMETER AREA SUBSURFACE SOIL (1-15 bgs) b (mg/kg)
PAL METALS
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Nickel
Potassium
Sodium
Vanadium
Zinc

PAL SEMIVOLATILE ORGANICS
bis (2-Ethylhexyl)phthalate
Di-n-butylphthaiate

PAL VOLATILE ORGANICS
Acetone
Trichlorofluoromethane
N/A
1.09 - 1.09
N/A
N/A
0.5 - 0.5
0.7 - 0.7
N/A
N/A
142 - 1.42
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0.62 - 3
0.061 - 0.3
0.017 - 0.017
0.0059 - 0.0059
15/15
1/15
15/15
15/15
1/15
1/15
15/15
15/15
14/15
15/15
15/15
15/15
15/15
15/15
15/15
15/15
15/15
15/15
15/15
2/15
3/15
1/15
9/15
2800
2.21
8.06
6.36
0.723
1.1
321
6.67
3.83
4.49
3540
3.18
1070
618
5.3
234
311
5.14
10.1
0.76
0.12
0.062
0.0057
13900
2.21
31
49
0.723
1.1
3920
55.4
14.8
38.6
26000
54
8220
890
50.2
2940
452
31.4
70.4
8.1
1.3
0.062
0.018
6932
0.7
16.9
19.3
0.3
0.4
1022.9
19.6
7.5
16.8
15577.3
10.7
3587.3
384.3
29.09
875.7
403.1
11.4
33.9
1.0
0.1
0.01
0.008
18000
0.5
19
54
0.81
1.28
810
33
4.7
13.5
18000
48
5500
380
14.6
2400
234
32.3
43.9
NDB
NDB
NDB
NDB
No
Yes
Yes
No
No
No
No
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
No
No
No
Yes
No
No
No
No
Background 1

Background 1
Background 1
Background 1
Essential Nutrient

Toxicity Value 3
Essential Nutrient

Essential Nutrient
Essential Nutrient
Background 1

Blank 4
Blank 4
Blank 4
Blank 4

2
2

OTHER
Total Petroleum Hydrocarbons
21.1 - 28.8
9/15
34.5
566
116.4
NDB
Yes Toxicity Value 3
-------
TABIiE 3
SUMMARY OF SUBSURFACE SOIL STATISTICS
AOC 43J - HISTORIC GAS STATION J
RECORD OF DECISION
FORT DEVENS,,MA
Frequency Detected
Range of of Concentrations
SOLs Detection Minimum Maximum
SOURCE AREA GROUNDWATER c (mg/L) - UNFILTERED
Mean
of all Back-
Samples Ground
CPC?
Notes
PAL METALS
Aluminum
Arsenic
Barium
Cadmium
Calcium
Chromium
Cobalt
Copper 0
Iron
Lead 0.
Magnesium
Manganese
Nickel 0
Potassium
Sodium
Vanadium
Zinc 0.
PAL SEMIVOLATILE ORGANICS
1,2-Dichlorobenzene 0.0017
1, 4-Dichlorobenzene 0.0017
2, 4-Dimethylphenol 0.0058
2-Methylnaphthalene 0.0017
2-Methylphenol 0.0039
4-Methllphenol 0.0005

0.141

0004

0.006
0.025
.0081

0013

.0343

0.011
0211

- 0.
- 0.
- 0.
- 0.
- 0.
- 0.
Bis (2-Ethylhexyl)phthalate 0.0048 -
Naphthalene 0.0005 -
PAL VOLATILE ORGANICS (mg/L)
Benzene 0.
Ethylbenzene 0.0005
Toluene
Xylene
Carbon Tetrachloride 0.0006
Chloroform 0.0005
Methyl ene Chloride 0.0023

05 -

-
NA
NA
-
NA
-
-
- 0
NA
- 0.
NA
NA
- 0
NA
NA
-
- 0.

0017
0017
0058
0017
0039
0005
- 0.

0.14111/12
12/12
12/12
0.004 1/12
12/12
0.006 7/12
0.025 1/12
.0081 5/12
12/12
0013 12/12
12/12
12/12
.0343 2/12
12/12
12/12
0.011 3/12
0211 6/12

3/12
1/12
1/12
9/12
2/12
4/12
1 9/12
0.0005 12/12

0.
- 0.0005

NA
NA
0.08
-
-
0.06
0.3

06 10/12
10/12
12/12
12/12
3/12
5/12
6/12

.285
0.00373
0.
0087
0.00579

40.7
0.00886
0.

0
0
0
0
0

0
0

0
0306
0.0136
8.07
.00126
7.67
1.65
0.0577
1.82
18.2
0.015
0.0293

.0048
.0036
.0088
.0062
.0041
0.002
.0061
.0041

.0015
0.14
.0053
0.008
0.02
0.001
.0034

21
0.0878
0.119
0.00579
87.7
0.0351
0.0306
0.0325
49.7
0.0267
18.2
18.2
0.0626
74.6
68.9
0.0276
0.62

0.014
0.0036
0.0088
0.1
0.0053
0.011
0.05
0.3

0.3
3
7
8
0.1
0.4
0.7

5.7
0.04
0.1
0.002
54.3
0.01
0.01
0.01
21.0
0.008
12.6
9.6
0.02
3.7
47.2
0.009
0.1

0.003
0.001
0.003
0.03
0.002
0.002
0.02
0.1

0.10
1.3
1.5
2.6
0.02
0.06
0.1

6.87
0.0105
0.0396
000401
14.7
0.0147
0.025
0.00809
9.1
0.00425
3.48
0.291
0.0343
2.37
10.8
0.011
0.0211

NDB
NDB
NDB
NDB
NDB
NDB
NDB
NDB

NDB
NDB
NDB
NDB
NDB
NDB
NDB

Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
yes
Yes
No
Yes
Yes
No
No
Yes
Yes

Yes
Yes
Yes
Yes
Yes
Yes
No
Yes

Yes
Yes
Yes
Yes
Yes
Yes
No
Essential Nutrient 2
Essential Nutrient 2
Essential Nutrient 2
Essential Nutrient 2
Blank 4
Blank 4
-------
SOURCE AREA GROUNDWATER c (mg/L) - FILTERED
PAL METALS
Antimony
Arsenic
Barium
Calcium
Copper
Iron
Lead
Magnesium
Manganese
Potassium
Sodium
0.003 - 0.003 1/12
NA 12/12
NA 12/12
NA 12/12
0.0081 - 0.0061 1/12
NA 12/12
0.0013 - 0.0013 5/12
NA 12/12
NA 1/12
NA 12/12
NA 12/12
0.00375 0.00375
0.00362 0.0726
0.00907 0.0298
42.4 61
0.0133 0.0133
0.391 30
0.00141 0.00618
6.57 15.6
3.28 18.4
1.48 3.38
20.2 67.7
0.002 0.00303 Yes
0.03 0.0105 Yes
0.02 0.0396 No
53.8 14.7 No
0.004 0.00809 Yes
10.5 9.1 Yes
0.002 0.00425 Yes
11 3.48 No
9.6 0.291 Yes
2.5 2.37 No
48 10.8 No
Background 1
Essential Nutrient 2
Essential Nutrient 2

Essential Nutrient 2
Essential Nutrient 2
-------
TABLE 3
SUMMARY OF SUBSURFACE SOIL STATISTICS
AOC 433 - HISTORIC GAS STATION J
RECORD OF DECISION
FORT DEVENS, MA
DOWNGRADIENT GROUNDWATER d
PAL METALS
Aluminum
Arsenic
Barium
Calcium
Chromium
Copper
Iron
Lead
Magnesium
Manganese
Nickel
Potassium
Sodium
Vanadium
Zinc
PAL SEMIVOLATILES
bis (2-Ethylhexyl)phthalate
Naphthalene
PAL VOLATILE ORGANICS
Benzene
Ethylbenzene
Toluene
Xylenes
Carbon Tetrachloride
Chloroform
Methylene Chloride
Freguency
Range of of
SOLs Detection
(mg/L) - UNFILTERED

0.141
0.0025
0.005

0.006
0.0081

- 0.141
- 0.0025
- 0.005
NA
- 0.006
- 0.0081
NA
0.0013 -

0.0343

0.011
0.0211 -

0.0048 -
0.0005 -

0.0005
0.0005
0.0005
0.0008
0.0006
0.0005
0.0023
0.0013
NA
NA
- 0.0343
NA
NA
- 0.011
0.0211

0.0048
0.0005

- 0.0005
- 0.0005
- 0.0005
- 0.0008
- 0.0006
- 0.0005
- 0.0023

8/8
5/8
8/8
8/8
2/8
1/8
8/8
4/8
8/8
8/8
1/8
8/8
8/8
1/8
1/8

4/8
1/8

2/8
2/8
3/8
2/8
1/8
2/8
1/8
Detected Mean
Concentrations of all Back-
Minimum Maximum Samples Ground

0.171
0.00277
0.00806
7.55
0.0104
0.015
0.0878
0.00184
1.11
0.0272
0.0559
0.509
6.3
0.016
0.0506

0.0048
0.0065

0.00056
0.00092
0.00073
0.0018
0.0033
0.00086
0.0037

13.9
0.0114
0.0991
48.3
0.0392
0.015
22.5
0.0144
23.7
2.33
0.0559
6.74
19.2
0.016
0.0506

0.041
0.0065

0.02
0.042
0.042
0.089
0.0033
0.0052
0.0037

2.5
0.004
0.03
32.2
0.008
0.005
4.7
0.004
11.5
0.8
0.02
3.4
11.5
0.007
0.02

0.009
0.001

0.003
0.006
0.006
0.01
0.0007
0.0009
0.001

6.87
0.0105
0.0396
14.7
0.0147
0.00809
9.1
0.00425
3.48
0.291
0.0343
2.37
10.8
0.011
0.0211

NDB
NDB

NDB
NDB
NDB
NDB
NDB
NDB
NDB
CPC? Notes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Yes
No
No
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Essential Nutrient 2
Essential Nutrient 2
Essential Nutrient 2
Essential Nutrient 2
Blank 4
Blank 4
-------
DOWNGRADIENT GROUNDWATER d (mg/L) - FILTERED
PAL METALS
Antimony
Arsenic
Barium
Calcium
Iron
Magnesium
Manganese
Potassium
Sodium
0
0.
0

.003
0025
.005

0.0388

.375

-
- 0
-
NA
- 0.
NA
NA
-
NA
0
.
0

.003
0025
.005

0388

.375

1/8
1/8
6/8
8/8
1/8
8/8
8/8
6/8
8/8
0.
0.
0.

0.
0

00491
00373
00519
9.24
0483
1.49
00681
.537
5.79
0.00491
0.00373
0.0219
60.5
0.0483
22.6
2.75
5.74
17.9
0.002
0.002
0.01
32.7
0.02
11.2
0.8
2.3
11.0
0.00303
0.0105
0.0396
14.7
9.1
3.48
0.291
2.37
10.8
Yes
No
No
No
No
No
Yes
No
No
Background 1
Background 1
Essential Nutrient 2
Background 1
Essential Nutrient 2

Essential Nutrient 2
Essential Nutrient 2
NOTE:

a Based on samples 43J-92-OIX,XJB-94-03X, -06X, -06X, -10X, -11X, -12X
b Based on samples XJM-93-01X and -02X, XJB-94-02X,-05X, -07X, 09X, -13X through 16x
c Based on samples XJM-94-05X, XJM-93-02X, 03X, 2446-02 TO -04
d Based on samples XJM-94-07X TO -10X

Background 1 - Sample concentrations detected are below background concentrations.
Essential Nutrient 2 - Analyte is an essential human nutrient (magnesium, calcium,
potassium, sodium and is not considered a CPC.
Toxicity Value 3 - Compound cannot be evaluated guantitatively because toxicity
values are not available.
Blank 4 - Compound was detected in field and/or laboratory blanks.
SQL - Sample Quantitation Limit
NDB - not detected in background
N/A - not applicable
mg - milligram
kg - kilogram
L - liter
CPC - chemical of potential concern
bgs - below ground surface
-------
CHEMICAL
OF
POTENTIAL
CONCERN(?)
TABIiE 4
GROUNDWATER CLEANUP GOALS
FOR SOURCE AREA GROUNDTCATER
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION
RECORD OF DECISION
FORT DEVENS, MA

SOURCE AREA GROUNDWATER(4) UPGRADIENTGROUNDWATER(5)
AVERAGE EPC MAXIMUM EPC AVERAGE EPC MAXIMUM EPC BKGRND(9)
(Ig/L) (Ig/L) (Ig/L) (Ig/L) SMCL MCL
UNFILTERED FILTERED UNFILTERED FILTERED UNFILTERED FILTERED UNFILTERED FILTERED (Ig/L)
ARARS
MMCL PRG
(Ig/L) (Ig/L)
PROPOSED
(Ig/L) (Ig/L) (8)
INORGANICS
Arsenic
Iron
Lead
Manganese
Nickel
VOCs
Benzene
Ethylbenzene
Xylenes
10
25,890
9
7, 600
50

620
430
3,360
10
18,030
1
7,500
30
57.7
87,200
49.1
14,300
209
24.1
54,100
3.04
15,200
180
26.9
16,615
21.5
795
63.2
1.7
ND
ND
24
ND
82.5
31,800
51.2
1,870
152
2.98
ND
ND
44.9
ND
10.5
9,100
4.25
291
34.3
-
300
-
50
-
50
-
15(3)
-
100
50
-
15
-
100
291
NA
NA
NA
2,000
2,000
20,000
NA
NA
NA
ND
ND
ND
NA
NA
NA
ND
ND
ND
NA
NA
NA
ND
ND
ND
5 5
700 700
10,000 10,000
-(6)
9,100
-(6)

100

5
700
10,000
Notes
(1)"Drinking Water Regulations and Health Advisories", May 1995, USEPA Office of Water
(2)"Drinking Water Standards & Guidelines for Chemicals in Massachusetts Drinking Waters". Autumn 1994, Massachusetts Department of Environmental Protection
(3)Action levels
(4)Based on samples XGM-94-03X and 04X, XGM-93-02X, and AAFES-1D, -2, -6.
(5)Based on samples XGM-93-01X and AAFES-3.
(6)MCL exceedance due to high total suspended solids content or MCL exceeded in upgradient samples.
(7)Analytes that exceed primary federal or Massachusetts drinking water standards or CPCs that present cancer risks above 10(-6) or HQs above 1.0 as identified by the baseline risk
assessment in the RI report.
(8)Proposed PRGs for inorganic analytes to be measured using filtered samples.
(9)Background concentrations determined from unfiltered samples from 10 wells at select locations on base. (Samples analyzed for Total Suspended Solids ranged from <4,000 to 53,000
Ig(L)
EPC - Exposure Point Concentration
ND - Not detected
NA - Not analyzed
MCL - Maximum Contaminant Level(1)
MMCL - Massachusetts Maximum Contaminant Level(2)
SMCL-Secondary MCL(l) based on aesthetics
HQ - Hazard Quotient
-------
TABIiE 5
GROUNDlflATER CIiEANUP GOALS
FOR DOWNGRADIENT AREA GROUNDWATER
AOC 43C - HISTORIC GAS STATION G /AAFES GAS STATION
CHEMICAL
OF
POTENTIAL
CONCERN(6)
RECORD OF DECISION
FORT DEVENS, MA
DOWNGRADIENT AREA GROUNDWATER(3)
AVERAGE EPC MAXIMUM EPC
(Ig/L) (Ig/L)
UNFILTERED FILTERED UNFILTERED FILTERED
UPGRADIENT GROUNDWATER (4)
AVERAGE EPC MAXIMUM EPC BKGRND(8)
(Ig/L) (Ig/L)
UNFILTERED FILTERED UNFILTERED FILTERED
PROPOSED
ARARs PRG
SMCL MCL MMCL (7)
(Ig/L) (Ig/L) (Ig/L) (Ig/L) (Ig/L)
INORGANICS
Arsenic
Manganese
VOCs
Benzene
10
5,200

20
10
5,300

NA
23.6
3, 630

79
14.1
8,820

NA
26.9
795

ND
1.7 82.5
24 1,870
NA
ND
2.!
44.9

NA
10.5
291 50

ND
50
50
291
-(5)
Notes:
(1)"Drinking Water Regulations and Health Advisories", May 1995, USEPA Office of Water
(2)"Drinking Water Standards & Guidelines for Chemicals in Massachusetts Drinking Waters", Autumn 1994, Massachusetts Department of Environmental Protection
(3)Based on samples XGM-94-06X to -08X,-10X.
(4)Based on samples XGM-93-01X and AAFES-3.
(5)Detected concentrations downgradient do not exceed MCL.
(6)Analytes that exceed primary federal or Massachusetts drinking water standards of CPCs that present cancer risks above 10 -6 or HQs above 1 as identified by the baseline risk
assessment in the RI report.
(7)Proposed PRGs for inorganic analytes to be measured using filtered samples.
(8) Background concentrations determined from unfiltered samples from 10 wells at select locations on base. (Samples analyzed for Total Suspended Solids ranged from <4,000 to
53,000 Ig/L).
EPC = Exposure Point Concentration
ND = Not detected
NA = Not analyzed
MCL = Maximum Contaminant Level(1)
HQ = Hazard Quotient
MMCL = Massachusetts Maximum Contaminant Level(2)
SMCL=Secondary MCL (1) based on aesthetics
-------
TABLE 6
GROUNDWATER CLEANUP GOALS
FOR SOURCE AREA GROUNDTCATER
AOC 43J- HISTORIC GAS STATION J
RECORD OF DECISION
FORT DEVENS, MA

CHEMICAL SOURCE AREA GROUNDWATER (4) UPGRADIENT GROUNDWATER (5)
OF AVERAGE EPC MAXIMUM EPC AVERAGE EPC MAXIMUM EPC
POTENTIAL (Ig/L) (Ig/L) (Ig/L) (Ig/L)
CONCERN(8)UNFILTERED FILTERED UNFILTERED FILTERED UNFILTERED FILTERED UNFILTERED FILTERED
INORGANICS
76.2
ND
30,000
6.18
18,400
BKGRND(
(Ig/L)
Arsenic
Cadmium
Iron
Lead
Manganese
VOCs
Benzene
Carbon
Tetrachloride
Ethylbenzene
Toluene
40
2
21,000
8
9, 600

100

20
1,300
1,500
30
ND
10,500
2
9, 600

NA
NA
NA
87.8
5.79
49,700
26.7
18,200

300

100
3,000
7,000
11.29
ND
31,050
16.4
1,066
ND
ND
51.05
ND
67.4
21.3
ND
43,200
24
1, 670
ND
ND
63.3
ND
107
10.5
4.01
9,100
4.25
291
NA

NA
NA
NA
ND

ND
ND
ND
NA

NA
NA
NA
ND

ND
ND
ND
NA

NA
NA
NA
ND

ND
ND
ND
ARARs PROPOSE
SMCL MCL MMCL PRG
(Ig/L)(Ig/L) (Ig/L)(Ig/L)
300
50
50
5

15 (3)
5
700
1,000
50
5
15
5
700
50
-(6)
9,100
-(7)
291
5
700
1,000 1,000
Notes:
(1)"Drinking Water Regulations and Health Advisories*, May 1995, USEPA Office of Water
(2)"Drinking Water Standards & Guidelines for Chemicals in Massachusetts Drinking Water", Autumn 1994, Massachusetts Department of Environmental Protection
(3)Action Level.
(4)Based on samples XJM-94-05X, XJM-93-02X, XJM-93-03X, 2446-02 to -04.
(5)Based on samples XJM-93-01X.
(6)Detected in 1 out of 12 samples. Not believed to be associated with site activities. (See Subsection 2.2.1)
(7)MCL exceedence due to high total suspended soils. Upgradient sample also exceeds MCL.
(8)Analytes that exceed primary federal of Massachusetts drinking water standards or CPCs that present cancer risks above 10 -6 or HQs above 1.0 as identified by the baseline risk
assessment in the RI Report.
(9)Background concentrations determined from unfiltered samples from 10 well sat select locations on base. (Samples analyzed for Total Suspended Solids ranged from <4,000 to 53,000
Ig/L)
(10)Proposed PRGs for inorganic analytes to be measured using filtered samples.
EPC = Exposure Point Concentration
ND = Not detected
NA = Not analyzed
MCL = Maximum Contaminant Level(1)
SMCL = Secondary MCL(l) based on aesthetics
HQ = Hazard Quotient
MMCL=Massachusetts Maximum Contaminant Level(2)
-------
TABLE 7
GROUNDWATER CLEANUP GOALS
FOR DOWNGRADIENT AREA GROUNDWATER
AOC 43J - HISTORIC GAS STATION J

RECORD OF DECISION
FORT DEVENS, MA
CHEMICAL DOWNGRADIENT AREA GROUNDWATER ( 3 ) UPGRADIENT GROUNDWATER ( 4 )
OF AVERAGE EPC MAXIMUM EPC AVERAGE EPC MAXIMUM EPC BKGRND(9) ARARs PROPOSED
POTENTIAL (Ig/L) (Ig/L) (Ig/L) (Ig/L) SMCL MCL MMCL PRG
CONCERN(8) UNFILITERED FILTERED UNFILITERED FILTERED UNFILITERED FILTERED UNFILITERED FILTERED (Ig/L) (Ig/L) (Ig/L) (Ig/L) (Ig/L) (7)
INORGANICS
Arsenic
Manganese
VOCs
Benzene
Cabron
Tetrachloride

4
800

0.7

2 11.4
800 2,330

NA 20

NA 3.3

3.73
2,750

11.29
1,066

ND
67.4

21.3
1, 670

ND
107

10.5
291

50
50

50
-

-(5,8)
291

-(8)
Notes:

(1)"Drinking Water Regulations and Health Advisories", May 1995, USEPA Office of Water
(2)"Drinking Water Standards & Guidelines for Chemicals in Massachusetts Drinking Waters", Autumn 1994, Massachusetts Department of Environmental Protection
(3)Based on samples XJM-94-7X to -10X.
(4)Based on samples XJM-93-01X.
(5)Unfiltered upgradient concentrations greater than downgradient concentrations.
(6)Analytes that exceed primary federal or Massachusetts drinking water standards or CPCs that present cancer risks above 10-6 or HQs above 1.0 as identified by the baseline risk
assessment in the RI Report.
(7)Proposed PRGs for inorganic analytes to be measured using filtered samples.
(8)No ARAR exceeded.
(9)Background concentrations determined from unfiltered samples from 10 wells at select locations on base. (Samples analyzed for Total Suspended Solids ranged from <4,000 to 53,000
Ig/L)
EPC = Exposure Point Concentration
ND = Not detected
NA = Not analyzed
MCL = Maximum Contaminant Level(1)
SMCL=Secondary MCL(l) based an aesthetics
HQ=Hazard Quotient
MMCL= Massachusetts Maximum Contaminant Level(2)
-------
TABLE 8
INTRINSIC BIOKEMEDIATION SAMPLING PARAMETERS
RECORD OF DECISION
AOC 43G
FORT DEVENS, MA
PARAMETER

DISSOLVED OXYGEN
REDOX (Eh)
NITRATE
NITRITE
PHOSPHATE
SULFATE
SULFIDE
TOTAL IRON

SOLUBLE IRON[FE(II)]
METHANE

BENZENE, XYLENE AND
ETHYLBENZENE
NICKEL, IRON AND
MANGANESE (filtered)
TEMPERATURE
PH
CONDUCTIVITY
ALKALINITY
AMMONIA-NITROGEN
TOTAL PETROLEUM
HYDROCARBONS
VOLATILE ORGANIC
COMPOUNDS
SEMI VOLATILE
ORGANIC COMPOUNDS
PURPOSE
defines zone of potential aerobic activity (greater than 0.5 mg/1)
define/confirm type of microbiological respiration process occurring
electron acceptor for anaerobic microbial respiration, microbial nutrient
electron acceptor for anaerobic microbial respiration, microbial nutrient
microbial nutrient
electron acceptor for anaerobic microbial respiration
product of sulfate-based microbial respiration
provides indication of anaerobic microbial respiration potential
(compared to filtered iron)
product of anaerobic biodegradation (compared to unfiltered iron)
product of carbonate-based (CO 2) microbial respiration (anaerobic
degradation of carbon at redox less than -200 mV)
Compare to groundwater cleanup levels, MCLs, or MMCLs

Compare to groundwater cleanup levels, MCLs, or MMCLs

well development/purge parameter
aguifer environment condition indicator
well development/purge parameter
well development/purge parameter
microbial nutrient, preliminary form of nitrite/nitrate under aerobic conditions
comparison to MADEP guidelines for VPH/EPH methods

compare to groundwater cleanup levels, MCLs, or MMCLs

compare to groundwater cleanup levels, MCLs, or MMCLs
-------
TABIiE 9
INTRINSIC BIOREMEDIATION SAMPLING PARAMETERS
AOC 43J - HISTORIC GAS STATION J
PARAMETER
DISSOLVED OXYGEN
REDOX (Eh)
NITRATE
NITRITE
PHOSPHATE
SULFATE
SULFIDE
TOTAL IRON

SOLUBLE IRON [FE(II)]
METHANE

PURPOSE
defines zone of potential aerobic activity (greater than 0.5 mg/1)
define/confirm type of microbiological respiration process occurring
electron acceptor for anaerobic microbial respiration, microbial nutrient
electron acceptor for anaerobic microbial respiration, microbial nutrient
microbial nutrient
electron acceptor for anaerobic microbial respiration
product of sulfate-based microbial respiration
provides indication of anaerobic microbial respiration potential
(compared to filtered iron)
product of anaerobic biodegradation (compared to unfiltered iron)
product of carbonate-based (C02) microbial respiration (anaerobic
degradation of carbon at redox less than -200 mV)
Compare to groundwater cleanup levels or MCLs/MMCLs

Compare to groundwater cleanup levels or MCLs/MMCLs

comparison to groundwater cleanup levels, MCLS, or MMCLs

comparison to groundwater cleanup levels, MCLs, or MMCLs
-------
TABIiE 10
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2A:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION

RECORD OF DECISION
FORT DEVENS, MA

LOCATION ACTION TO BE TAKEN
AUTHORITY SPECIFIC REQUIREMENT STATUS REQUIREMENT SYNOPSIS TO ATTAIN REQUIREMENT
Federal No location-specific
Regulatory ARARs will be
Authority triggered.

State No location-specific
Regulatory ARARs will be
Authority triggered.
-------
TABLE 10
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE, 2A:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION
AUTHORITY
CHEMICAL
SPECIFIC
REQUIREMENT
RECORD OF DECISION
FORT DEVENS, MA
STATUS
REQUIREMENT SYNOPSIS
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT
Federal
Regulatory
Authority
Groundwater
(Also
applicable as
an Action
Specific
ARAR)
Federal
Regulatory
Authority

Federal
Regulatory
Authority
Groundwater
Groundwater
SDWA, National
Primary Drinking Water
Standards, MCLs [40
CFR Parts 141.11 -
141.16 and 141.50 -
141.52]
USEPA Reference
Dose
USEPA HAs
Relevant
and
Appropriate
TBC
TBC
The NPDWR establishes
MCLs for several common
organic and inorganic
contaminants. MCLs specify
the maximum permissible
concentrations of
contaminants in public
drinking water supplies. MCLs
are federally enforceable
standards based in part on the
availability and cost of
treatment technigues.
Biodegradation of organic
contaminants exceeding
MCLs is believed to be
occurring under existing
conditions. MCLs will be
used to evaluate the
performance of this
alternative through
implementation of a long-
term groundwater monitoring
program will achieve MCL
at completion of remedy.
-------
TABIiE 10
SYNOPSIS OF FEDERAL AND STATE ARARs FOR ALTERNATIVE 2A:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION
AUTHORITY
CHEMICAL
SPECIFIC
RECORD OF DECISION
FORT DEVENS, MA
REQUIREMENT
Groundwater Massachusetts Drinking
(Also
applicable as
an Action
Specific
ARAR)
Water Standards and
Guidelines [310 CMR
22.01].
STATUS

Relevant
and
Appropriate
REQUIREMENT SYNOPSIS

The Massachusetts Drinking
Water Standards and
Guidelines list MMCLs which
apply to water delivered to
any user of a public water
supply system as defined in
310 CMR 22.00. Private
residential wells are not
subject to the reguirements of
310 CMR 22.00; however, the
standards are often used to
evaluate private residential
contamination especially in
CERCLA activities.
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT

Biodegradation of organic
contaminants exceeding
MMCLs is believed to be
occurring under existing
conditions. MMCLs will be
used to evaluate the
performance of this
alternative through
implementation of a long-
term groundwater monitoring
program.
-------
TABIiE 10
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2A:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION
RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY
ACTION
SPECIFIC
REQUIREMENTS
STATUS
REQUIREMENT SYNOPSIS
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT
Federal
Regulatory
Authority

StateGroundwater
Regulatory
Authority
Groundwater
RCRA Subtitle C
Subpart F
Massachusetts
Groundwater
Quality Standards
[314 CMR 6.00]
Relevant
and
Appropriate

Applicable
Groundwater protection
standard.
Massachusetts Groundwater
Quality Standards designate
and assign uses for which
groundwater of the
Commonwealth shall be
maintained and protected
and set forth water quality
criteria necessary to
maintain the designated
uses. Groundwater at Fort
Devens is classified as Class
1. Groundwater assigned to
this class are fresh
groundwater designated as a
source of potable water
supply.
Biodegradation of organic
contaminants exceeding MMCL-s
is believed to be occurring under
existing conditions. MMCLs will
be used to evaluate the
performance of this alternative
through implementation of a
long-term groundwater
monitoring program.
-------
TABIiE 10
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2A:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION

RECORD OF DECISION
FORT DEVENS, MA

ACTION ACTION To BE TAKEN
AUTHORITY SPECIFIC REQUIREMENTS STATUS REQUIREMENT SYNOPSIS TO ATTAIN REQUIREMENT

State Groundwater Massachusetts Relevant Groundwater monitoring is A long-term groundwater
Regulatory Monitoring Hazardous Waste and reguired during and monitoring program is to be
Authority Management Appropriate following remedial actions. implemented to monitor the
Rules (MHWMR) progress of remediation.
Groundwater
Protection;[310
CMR 30.660-
30.679]

Notes:

CERCLA = Comprehensive Environmental Response, Compensation and Liability Act MMCLs = Massachusetts Maximum Contaminant Levels
MCLs = Maximum Contaminant Levels NPDWR - National Primary Drinking Water Standards
MHWMR = Massachusetts Hazardous Waste Management Rules SDWA = Safe Drinking Water Act
-------
TABIiE 11
SYNOPSIS OF FEDERAL AND STATE ARARs FOR ALTERNATIVE 2B:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION
AUTHORITY

Federal
Regulatory
Authority

State
Regulatory
Authority
LOCATION
SPECIFIC
RECORD OF DECISION
FORT DEVENS, MA
REQUIREMENT
No location-specific
ARARs will be
triggered.

No location-specific
ARARs will be
triggered.
STATUS
REQUIREMENT SYNOPSIS
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT
-------
TABIiE 11
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2B:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY

Federal
Regulatory
Authority
CHEMICAL
SPECIFIC

Groundwater
(Also
applicable as
an Action Sp-
ecific
ARAR)
REQUIREMENT

SDWA, National
Primary Drinking Water
Standards, MCLs {40
CFR Parts 141.11 -
141.16 and 141.50 -
141.521
STATUS

Relevant
and
Appropriate
Federal
Regulatory
Authority

Federal
Regulatory
Authority
Groundwater
Groundwater
USEPA Reference
Dose
USEPA HAs
TBC
TBC
REQUIREMENT SYNOPSIS

The NPDWR establishes
MCLs for several common
organic and inorganic
contaminants. MCLs specify
the maximum permissible
concentrations of
contaminants in public
drinking water supplies. MCLs
are federally enforceable
standards based in part on the
availability and cost of
treatment technigues.
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT

Biodegradation of organic
contaminants exceeding
MCLs is believed to be
occurring under existing
conditions. MCLs will be
used to evaluate the
performance of this
alternative through
implementation of a long-
term groundwater monitoring
program will achieve MCLs
at completion of remedy.
-------
TABLE 11
SYNOPSIS OF FEDERAL AND STATE ARARs FOR ALTERNATIVE 2B:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY

Continued
CHEMICAL
SPECIFIC

Groundwater
(Also
applicable as
an Action
Specific
ARAR)
REQUIREMENT

Massachusetts Drinking
Water Standards and
Guidelines [310 CMR
22.0] .
STATUS REQUIREMENT SYNOPSIS

Relevant The Massachusetts Drinking
and Water Standards and
Appropriate Guidelines list MMCLs which
apply to water delivered to
any user of a public water
supply system as defined in
310 CMR 22.00. Private
residential wells are not
subject to the reguirements of
310 CMR 22.00; however, the
standards are often used to
evaluate private residential
contamination especially in
CERCLA activities.
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY
ACTION
SPECIFIC
REQUIREMENT
STATUS
REQUIREMENT SYNOPSIS
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT
Disposal of
treatment
residues
RCRA, Land
Disposal
Restrictions [40
CFR 268]
Applicable
Land disposal of RCRA
hazardous wastes without
specified treatment is
restricted. LDRs require
that wastes must be treated
either by a treatment
technology or to a specific
concentration prior to
disposal in a RCRA Subtitle
C permitted facility.
SVE carbon would be tested to
evaluate characteristics for
proper disposal/reactivation.
-------
TABIiE 11
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2B:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY
ACTION
SPECIFIC
REQUIREMENT
STATUS
REQUIREMENT SYNOPSIS
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT
Groundwater
Massachusetts
Groundwater
Quality Standards
[314 CMR 6.00]
Applicable
State
Regulatory
Authority
Groundwater
Monitoring
Massachusetts
Hazardous Waste
Management
Rules (MHWMR)
Groundwater
Protection; [310
CMR 30.660-
30.679]
Relevant
and
Appropriate
Massachusetts Groundwater
Quality Standards designate
and assign uses for which
groundwater of the
Commonwealth shall be
maintained and protected
and set forth water guality
criteria necessary to
maintain the designated
uses. Groundwater at Fort
Devens is classified as Class
1. Groundwater assigned to
this class are fresh
groundwater designated as a
source of potable water
supply.

Groundwater monitoring is
required during and
following remedial actions.
Biodegradation of organic
contaminants exceeding MMCLs
is believed to be occurring under
existing conditions. MMCLs will
be used to evaluate the
performance of this alternative
through implementation of a
long-term groundwater
monitoring program.
A long-term groundwater
monitoring program is to be
implemented to monitor the
progress of remediation.
-------
TABIiE 11
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2B:
INTRINSIC BIOREMEDIATION
AOC 43G - HISTORIC GAS STATION G/AAFES GAS STATION

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY

Continued
ACTION
SPECIFIC

SVE
Treatment
REQUIREMENT

Massachusetts Air
Pollution Control
Regulations [310
CMR 6.00-7.00]
STATUS
Applicable
REQUIREMENT SYNOPSIS

SVE system must reduce
VOCs in air effluent stream
by at least 95% by weight.
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT

Emissions will be managed
through engineering controls.
Notes:
CERCLA =Comprehensive Environmental Response, Compensation and Liability Act
MCLs = Maximum Contaminant Levels
MHWMR = Massachusetts Hazardous Waste Management Rules
MMCLs = Massachusetts Maximum Contaminant Levels
NPDWR = National Primary Drinking Water Standards
SDWA = Safe Drinking Water Act
-------
TABIiE 12
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2:
INTRINSIC BIOREMEDIATION
AOC 43J - HISTORIC GAS STATION J

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY

Federal
Regulatory
Authority

State
Regulatory
Authority
LOCATION
SPECIFIC
REQUIREMENT

No location-specific
ARARs will be
triggered.

No location-specific
ARARs will be
triggered.
STATUS
REQUIREMENT SYNOPSIS
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT
-------
TABIiE 12
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2:
INTRINSIC BIOREMEDIATION
AOC 43J - HISTORIC GAS STATION J

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY

Federal
Regulatory
Authority
CHEMICAL
SPECIFIC

Groundwater
(Also
applicable as
an Action
Specific
ARAR)
REQUIREMENT

SDWA, National Primary
Drinking Water Standards,
MCLs [40 CFR Parts
141.11 - 141.16 and 141.50
-141.52]
STATUS

Relevant and
Appropriate
REQUIREMENT SYNOPSIS

The NPDWR establishes MCLs
for several common organic and
inorganic contaminants. MCLs
specify the maximum permissible
concentrations of contaminants in
public drinking water supplies.
MCLs are federally enforceable
standards based in part on the
availability and cost of treatment
technigues.
Federal
Regulatory
Authority

Federal
Regulatory
Authority
Groundwater
Groundwater
USEPA Reference Dose
USEPA HAs/TBC
TBC
TBC
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT

Biodegradation of organic
contaminants exceeding MCLs is
believed to be occurring under
existing conditions. MCLs will
be used to evaluate the
performance of this alternative
through implementation of a
long-term groundwater
monitoring program will achieve
MCLs at completion of remedy.
-------
TABIiE 12
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2:
INTRINSIC BIOREMEDIATION
AOC 43J - HISTORIC GAS STATION J

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY

State
Regulatory
Authority
CHEMICAL
SPECIFIC

Groundwater
(Also
applicable as
an Action
Specific
ARAR)
REQUIREMENT

Massachusetts Drinking
Water Standards and
Guidelines [310 CMR
22.0] .
STATUS REQUIREMENT SYNOPSIS

Relevant and The Massachusetts Drinking
Appropriate Water Standards and Guidelines
list MMCLs which apply to water
delivered to any user of a public
water supply system as-defined in
310 CMR 22.00. Private
residential wells are not subject to
the reguirements of 310 CMR
22.00; however, the standards are
often used to evaluate private
residential contamination
especially in CERCLA activities.
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY

Federal
Regulatory
Authority
ACTION
SPECIFIC
Groundwater
REQUIREMENT

RCRA Subtitle C
Subpart F
Massachusetts
Groundwater
Quality Standards
[314 CMR 6.00]
STATUS REQUIREMENT SYNOPSIS

Relevant and Groundwater protection
Appropriate standards.
Applicable Massachusetts Groundwater
Quality Standards designate and
assign uses for which
groundwater of the
Commonwealth shall be
maintained and protected and
set forth water guality criteria
necessary to maintain the
designated uses. Groundwater
at Fort Devens is classified as
Class 1. Groundwater assigned
to this class are fresh
groundwater designated as a
source of potable water supply.
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT
Biodegradation of organic
contaminants exceeding MMCLs is
believed to be occurring under
existing conditions. MMCLs will
be used to evaluate the
performance of this alternative
through implementation of a long-
term groundwater monitoring
program.
-------
TABIiE 12
SYNOPSIS OF FEDERAL AND STATE ARARS FOR ALTERNATIVE 2:
INTRINSIC BIOREMEDIATION
AOC 43J - HISTORIC GAS STATION J

RECORD OF DECISION
FORT DEVENS, MA
AUTHORITY

State
Regulatory
Authority
ACTION
SPECIFIC

Groundwater
Monitoring

(MHWMR)
Groundwater
Protection; [310
CMR 30.660-30.679]
REQUIREMENT

Massachusetts
Hazardous Waste
Management Rules
STATUS REQUIREMENT SYNOPSIS

Relevant and Groundwater monitoring is
Appropriate reguired during and following
remedial actions.
progress of remediation.
ACTION TO BE TAKEN
TO ATTAIN REQUIREMENT

A long-term groundwater
monitoring program is to be
implemented to monitor the
Notes:
CERCLA = Comprehensive Environmental Response, Compensation and Liability Act
MCLs = Maximum Contaminant Levels
MHWMR = Massachusetts Hazardous Waste Management Rules
MMCLs = Massachusetts Maximum Contaminant Levels
NPDWR = National Primary Drinking Water Standards
SDWA = Safe Drinking Water Act
-------
APPENDIX C - RESPONSIVENESS SUMMARY

This Responsiveness Summary has been prepared to meet the requirements of Sections 113(k)(2)(B)(iv) and
117(b) of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) as
amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA) , which requires response to
"... significant comments, criticisms, and new data submitted in written or oral presentations" on a
proposed plan for remedial action. The purpose of this Responsiveness Summary is to document Army
responses to questions and comments expressed during the public comment period by the public, potentially
responsible parties, and governmental bodies in written and oral comments regarding the proposed plan for
the groundwater cleanup at Area of Contamination (AOCs) 43G and 43J.

The Army held a 30-day public comment period from August 26 to September 25, 1996 to provide an
opportunity for interested parties to comment on the Feasibility Study (FS) , proposed plan, and other
documents developed to address the cleanup of contaminated groundwater at AOC 43G and 43J at Devens,
Massachusetts. The FS developed and evaluated various options (referred to as remedial alternatives) to
address human health from exposure to contaminated groundwater and potential migration of substances
present in groundwater at both AOC 43G and 43J. The Army identified its preferred alternative for cleanup
of groundwater in the proposed plan issued on August 25, 1996.

All documents on which the preferred alternative were based were placed in the Administrative Record for
review. The Administrative Record contains all supporting documentation considered by the Army in
choosing the remedy for both AOC 43G and 43J. The administrative Record is available to the public at the
Devens Base Realignment and Closure (BRAG) Environmental Office, Building P-12, Devens, and at the Ayer
Town Hall, Main Street, Ayer. An index to the Administrative Record is available at the U.S.
Environmental Protection Agency (USEPA) Records Center, 90 Canal Street, Boston, Massachusetts and is
provided as Appendix D to the Record of Decision.

This Responsiveness Summary is organized into the following sections:

I. Overview of Remedial Alternatives Considered in the FS Including the Selected Remedy - This
section briefly outlines the remedial alternatives evaluated in detail in the FS and presented in
the proposed plan, including the Army's selected remedies.

II. Background on Community Involvement - This section provides a brief history of community
involvement and Army initiatives in informing the community of site activities.

III. Summary of Comments Received During the Public Comment Period and Army Responses - This section
provides Army responses to oral and written comments received from the public and not formally
responded to during the public comment period. A transcript of the public meeting consisting of
all comments received during this meeting and the Army's responses to these comments is provided
in Attachment A of this Responsiveness Summary.
I. OVERVIEW OF REMEDIAL ALTERNATIVES CONSIDERED IN THE FS INCLUDING THE SELECTED REMEDY

Five remedial alternatives were developed in the AOC 43G and 43J FS reports and screened based on
implementability, effectiveness, and cost to narrow the number of remedial alternatives for detailed
analysis. All five alternatives were retained in each FS for detailed evaluation. The five retained
alternatives are:

AOC 43G

A. Alternative 1: No Action

B. Alternative 2A: Intrinsic Bioremediation

Intrinsic bioremediation is the principal component in Alternative 2A that is proposed to prevent
chemicals of potential concern (CPCs) that exceed groundwater cleanup levels from potentially migrating
off the Army property and to reduce contaminants on Army property to below groundwater cleanup goals. The
installation of additional monitoring wells and implementation of a long-term groundwater monitoring
-------
program will enable assessment of the biodegradation progress and permit detection of any potential
migration of contaminants beyond the Devens. Reserve Forces Training Area boundary. Key components of
this alternative include:

• intrinsic bioremediation
• intrinsic bioremediation assessment data collection and groundwater modeling
• installing additional groundwater monitoring wells
• long-term groundwater monitoring
• annual data reports to U.S. Environmental Protection-Army (USEPA) and Massachusetts
Department of Environmental Protection (MADEP)
• five-year site reviews

The Army's selected remedy is Alternative 2A.

C. Alternative 2B: Intrinsic Bioremediation/Soil Venting of Gasoline UST Soils

Like Alternative 2A, intrinsic bioremediation is the principal component in Alternative 2B that is
proposed to prevent CPCs that exceed groundwater cleanup levels from potentially migrating off the Army
property and to reduce on- site contaminants to below groundwater cleanup goals. However, Alternative 2B
also includes installation of an SVE system to reduce residual contaminant concentrations in soils below
the former gasoline underground storage tanks (USTs) (now adjacent and below the existing gasoline USTs).
The objective of the soil vapor extraction (SVE) system is to remediate the vadose zone soils below the
former gasoline UST, to prevent further potential contamination of the aguifer. The soils that contain
volatile organic compounds (VOCs) may contribute to groundwater contamination during periods of high
water table conditions. Minimizing the potential re-contamination of groundwater will improve the
effectiveness of intrinsic bioremediation. The following specific actions are included in Alternative 2B:

• intrinsic bioremediation
• intrinsic bioremediation assessment data collection / groundwater modeling
• installing additional groundwater monitoring wells
• SVE treatment system installation and operation
• Soil vapor monitoring
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews

D. Alternative 3: Groundwater Collection and Treatment/Intrinsic Bioremediation

• intrinsic bioremediation
• intrinsic bioremediation data collection and design
• groundwater treatment facility construction
• groundwater treatment facility operation and maintenance
• installing additional groundwater monitoring wells
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews

E. Alternative 4: Intrinsic Bioremediation/Hydraulic Containment

Alternative 4 for AOC 43G is designed to reduce potential future human health risks. In addition to the
components of Alternative 3, this alternative provides installation of passive in-situ bioremediation
wells to reduce potential future risk to downgradient receptors from potentially contaminated
groundwater. The following specific actions are included in Alternative 4:
-------
• intrinsic bioremediation
• installing passive in-situ bioremediation wells
• passive in-situ bioremediation system maintenance
• intrinsic bioremediation assessment data collection and design
• groundwater treatment facility construction
• groundwater treatment facility operation and maintenance
• installing additional groundwater monitoring wells
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews

AOC 43J

A. Alternative 1: No Action

The No Action alternative serves as a baseline alternative with which to compare other remedial
alternatives for AOC 43J. The No Action alternative does not contain any additional remedial action
components to reduce or control potential risks. Existing activities to maintain existing systems and
monitor for potential contaminant migration would be discontinued.

B. Alternative 2: Intrinsic Bioremediation

Intrinsic bioremediation is the principal component in Alternative 2 that is proposed to reduce
contaminants on Army Reserve Enclave property to below PRGs and also to prevent potential migration of
contaminants above PRGs off Army Reserve Enclave property. The installation of additional monitoring
wells and implementation of a long term groundwater monitoring program will enable assessment of the
biodegradation progress and permit detection of any potential migration of contaminants beyond the Army
Reserve Enclave boundary. Key components of this alternative include:

C. Alternative 3: Intrinsic Bioremediation / Passive In-Situ Bioremedial Containment

Alternative 3 for AOC 43J is designed to reduce potential future human health risks. In addition to the
components of Alternative 2, this alternative provides installation of passive bioremediation wells to
reduce potential future risk to downgradient receptors from potentially contaminated groundwater. The
following specific actions are included in Alternative 3:

• intrinsic bioremediation
• installing passive bioremediation wells
• passive in-situ bioremediation system maintenance
• intrinsic bioremediation assessment data collection and groundwater modeling
• installing additional groundwater monitoring wells
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews

D. Alternative 4: Intrinsic Bioremediation / Hydraulic Containment

Alternative 4 for AOC 43J is designed to reduce potential future human health risks by using intrinsic
bioremediation to degrade CPCs below groundwater cleanup levels on site and using groundwater extraction
and treatment to hydraulically contain and also to treat the contaminant plume. This alternative is
similar to Alternative 3 except the plume would be contained hydraulically rather than by aerobic
biodegradation to reduce potential future risk to downgradient receptors. Calculations based on site soil
and contaminant characteristics reveal that up to 56 years may be required to remove all the
contamination in the aguifer using pumping remediation alone (no abiotic removal or biological
degradation effects). Intrinsic bioremediation is expected to reduce CPCs to below groundwater cleanup
levels in less time as will be detailed below. Therefore, the groundwater extraction and treatment
component in this alternative serves more for hydraulic containment of the contaminant plume while
reduction of contaminant concentrations would be shared both by intrinsic bioremediation and groundwater
extraction. Extraction wells would be positioned within the higher contaminated portion of the plume to
-------
maximize treatment efficiency for this Alternative. The following specific actions are included in
Alternative 4:

E. Alternative 5: Groundwater Collection and Treatment / Soil Treatment

• intrinsic bioremediation assessment data collection and design
• SVE treatment system installation
• groundwater treatment facility construction
• installing additional groundwater monitoring wells
• groundwater treatment facility operation and maintenance
• soil monitoring
• long-term groundwater monitoring
annual data reports to USEPA and MADEP
• five-year site reviews
• intrinsic bioremediation

II. BACKGROUND ON COMMUNITY INVOLVEMENT

Community concern and involvement have been low throughout the history of the AOC 43G and 43J
investigations. Although the Army has kept the community and other interested parties informed of site
activities through regular and freguent informational meetings, press releases, and a public meeting, no
members of the public attended the public meeting on the proposed plan.

In February 1992, the Army released, following public review, a community relations plan that outlined a
program to address community concerns and keep citizens informed about and involved in remedial
activities at Fort Devens. As part of this plan, the Army established a Technical Review Committee (TRC)
in early 1992. The TRC, as reguired by SARA Section 211 and Army Regulation 200-1, included
representatives from USEPA, U.S. Army Environmental Center (USAEC), Fort Devens, MADEP, local officials
and the community. Until January 1994, when it was replaced by the Restoration Advisory Board (RAB), the
committee generally met guarterly to review and provide technical comments on schedules, work plans, work
products, and proposed activities for the Study Areas at Devens. The Remedial Investigation (RI), and FS
reports, proposed plan, and other related support documents were all submitted to the TRC or RAB for
their review and comment.

The Army, as part of its commitment to involve the affected communities, forms a RAB when an installation
closure involves transfer of property to the community. The Fort Devens RAB was formed in February 1994
to add members of the Citizen's Advisory Committee (CAC) to the TRC. The CAC had been established
previously to address Massachusetts Environmental Policy Act/Environmental Assessment issues concerning
the reuse of property at Fort Devens. The RAB consists of 28 members (15 original TRC members plus 13 new
members) who are representatives from the Army, USEPA Region 1, MADEP, local governments and citizens of
the local communities. It meets monthly and provides advice to the installation and regulatory agencies
on Devens cleanup programs. Specific responsibilities include: addressing cleanup issues such as land use
and cleanup goals; reviewing plans and documents; identifying proposed reguirements and priorities; and
conducting regular meetings that are open to the public.
-------
On August 25, 1996, the Army issued the final proposed plan to citizens and organizations, to provide the
public with a explanation of the Army's preferred remedies for cleanup of groundwater at AOC 43G and 43J.
The proposed plan also described the opportunities for public participation and provided details on the
upcoming public comment period and public meetings.

During the week of August 25, the Army published a public notice announcing the proposed plan and public
meeting in the Times Free Press and the Lowell Sun. The Army also made the proposed plan available to the
public at the information repositories at the libraries in Ayer, Shirley, Lancaster, Harvard and at
Devens BRAG Environmental Office.

From August 26 to September 25, 1996, the Army held a 30-day public comment period to accept public
comments on the alternatives presented in the FS and the proposed plan and on other documents released to
the public. On September 5, 1996, the Army held a public meeting at Devens to present the Army's proposed
plan to the public and discuss the cleanup Alternatives evaluated in the FS. This meeting also provided
the opportunity for open discussion concerning the proposed cleanup.

All supporting documentation for the decision regarding AOC 43G and 43J is contained in the
Administrative Record for review. The Administrative Record is a collection of all the documents
considered by the Army in choosing the remedies at AOC 43G and 43J. On June 2, 1995, the Army made the
Administrative Record available for public review at the Devens BRAG Environmental Office, and at the
Ayer Town Hall, Ayer, Massachusetts. An index to the Administrative Record is available at the USEPA
Records Center, 90 Canal Street, Boston, Massachusetts and is provided as Appendix D.

III. SUMMARY OF COMMENTS RECEIVED DURING THE PUBLIC COMMENT PERIOD AND ARMY RESPONSES

No comments were received during the public comment period.
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ATTACHMENT A - PUBLIC MEETING TRANSCRIPT

1 PROCEEDINGS

2 MR. CHAMBERS: Good evening. Welcome to

3 the public hearing for the proposed plan for areas

4 of contamination 43G and 43J, historic gas stations

5 at Ft. Devens, Massachusetts.

6 My name is James Chambers. I'm the BRAG

7 environmental coordinator, Base Realignment and

8 Closure environmental coordinator for the U.S. Army

9 at Ft. Devens.

10 This evening we're going to hold this

11 public hearing to solicit comments on the proposed

12 plan for remediation of these historic gas

13 stations. What I would like to do is remind you

14 that we are sending around an attendance sheet.

15 We're required to maintain that as a public record

16 for who is at this hearing. So, please, do sign

17 it.

18 Also -- I'm going to solicit your

19 comments. I'll mention that the public comment

20 period began August 26th and is ongoing through

21 September 25th. It's a 30-day public comment

22 period. At that time we will respond formally to

23 those comments and include that in the

24 administrative record for the Record of Decision.

DORIS 0. WONG ASSOCIATES
-------
1 The Record of Decision will be a record of what

2 will -- what the Army will do as a remedial action

3 at these sites.

4 So, again, please stand up when you want to

5 make a comment, and speak clearly and loudly for the

6 stenographer to record your statements. Please

7 announce your name and where you're from. And then

8 I guess if you have guestions during that time as

9 well, we'll try to respond to the guestions if we

10 can this evening, but otherwise we may wait and

11 respond to them formally in the response summary.

12 Is there any -- would anybody like to make

13 a comment? Going once?

14 MR. MacIVER: Could we hear from other

15 agencies, such as DEP and EPA, just a general

16 feeling about this? Maybe that would be helpful. I

17 realize this is a public comment period and they are

18 agencies, but it might be helpful just to have a

19 general sense from those groups.

20 MR. CHAMBERS: Okay. I'll offer them that

21 opportunity, but I will state that all through the

22 process the regulators are involved, and they

23 comment, and their comments are recorded as part of

24 the administrative record. So I'll invite them to

DORIS 0. WONG ASSOCIATES
-------
1 make a comment now if they would like to, but

2 understand, if they want, to do so formally.

3 MR. MacIVER: Realizing it isn't a

4 judgment, just an informal comment.

5 MS. WELSH: I'll take a stab. I'm Lynn

6 Welsh from the Massachusetts Department of

7 Environmental Protection, and I'm going to sit

8 down.

9 We are actually sort of excited to try this

10 method here at Ft. Devens and see it as a good

11 location. There are concerns: Is it really

12 happening? Have we done enough work to know exactly

13 what the contaminant situation is?

14 But it's something that the industry and

15 the sort of environmental community have been

16 looking at for a while, instead of going to

17 aggressive pump and treat or extensive studies to

18 see what the contamination is. There is a lot of

19 work -- science starting to be developed and, as I

20 said, proved. So at least it is out there and being

21 studied by universities and other people involved

22 the field.

23 So it makes sense to give it a try at a

24 location that isn't problematic. It is sort of the

DORIS 0. WONG ASSOCIATES
-------
1 edge of the Army property, but EPA is involved, and

2 these people here are pretty intent on doing regular

3 monitoring and regular evaluations and setting up

4 reasonable points where we'll make other decisions.

5 MR. KEEFE: I'm Jerry Keefe of the EPA.

6 This was one of my -- two of my sites. We look at

7 intrinsic bioremediation as a process that is going

8 to last a long period of time. The monitoring of it

9 will be effective enough to be able to see if the

10 degradation is occurring effectively. We've done

11 this at a few other sites. Pease Air Force Base, we

12 have a natural attenuation ROD up there, and we're

13 working on one also up at Loring in Maine.

14 So we're pretty familiar with what should

15 be monitored for and what characteristics to look

16 for to ensure biodegradation is occurring as well as

17 contamination decrease. And there are other

18 nutrients and things that you look for. To be more

19 specific, the monitoring plan that we're going to

20 develop will really bring it all together. So we

21 can be pretty confident of the plan and are excited

22 to have one here at Devens.

23 MR. CHAMBERS: Is there any — would

24 anybody else like to comment?

DORIS 0. WONG ASSOCIATES
-------
1 MR. MacIVER: My name is Don Maclver. I'm

2 a resident of Littleton. I sit here representing

3 the Massachusetts Association of Conservation

4 Commissions.

5 I would like to thank you for the

6 opportunity for the presentation. It sounds

7 encouraging from what I've heard and what I've read,

8 and it sounds as if it's somewhat innovative,

9 certainly innovative technology. Environmental

10 matters have been a concern for Ft. Devens, so it

11 sounds encouraging and sounds like there are

12 contingency plans in case the chosen method does no,

13 work. So it sounds encouraging. Thank you.

14 MR. CHAMBERS: Thank you.

15 Would anybody else like to comment? Going

16 once? Twice? Three times. (No response)

17 Thank you. This closes the public hearing

18 portion of this meeting. Again I remind you that

19 the public comment period extends to September 25th,

20 so you are welcome to submit your comments in

21 writing by that date.

22 (Whereupon the hearing was

23 adjourned at 7:40 p.m.)

DORIS 0. WONG ASSOCIATES
-------
1 CERTIFICATE

2 I, Carol H. Kusinitz, Registered

3 Professional Reporter, do hereby certify that the

4 foregoing transcript, Volume I, is a true and

5 accurate transcription of my stenographic notes

6 taken on September 5, 1996.

DORIS 0. WONG ASSOCIATES
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APPENDIX D - ADMINISTRATIVE RECORD INDEX

Fort Devens

Groups 2 & 7 Sites

Administrative Record File for

Index

Prepared for
New England Division
Corps of Engineers

by
ABB ENVIRONMENTAL SERVICES, INC.
107 Audubon Road, Wakefield, Massachusetts 01830 (617) 245-6606

Introduction

This document is the Index to the Administrative Record File for the Fort Devens Groups 2 & 7 Sites.
Section I of the Index cites site-specific documents and Section II cites guidance documents used by U.S.
Army staff in selecting a response action at the site. Some documents in this Administrative Record File
Index have been cited but not physically included. If a document has been cross-referenced to another
Administrative Record File Index, the available corresponding comments and responses have been
cross-referenced as well.

The Administrative Record File is available for public review at EPA Region I's Office in Boston,
Massachusetts, at the Fort Devens Environmental Management Office, Fort Devens, Massachusetts, and at the
Ayer Town Hall, 1 Main Street, Ayer, Massachusetts. Supplemental/Addendum volumes may be added to this
Administrative Record File. Questions concerning the Administrative Record should be addressed to the
Fort Devens Base Realignment and Closure Office (BRAG).
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Section I

Site-Specific Documents

ADMINISTRATIVE RECORD INDEX FILE

for

Fort Devens Groups 2 & 7 Sites

Compiled: April 22, 1996

1.0 Pre-Remedial

1.2 Preliminary Assessment

Cross Reference: The following Reports, Comments, and Responses to Comments (entries 1
through 6) are filed and cited as entries 1 through 6 in minor break 1.2 Preliminary
Assessment of the Fort Devens Group 1A Administrative Record File Index.

Reports

1. "Final Master Environmental Plan for Fort Devens," Argonne National Laboratory (April
1992).
2. "Preliminary Zone II Analysis for the Production Wells at Fort Devens, MA., Draft
Report", ETA Inc. (January 1994).

Comments

3. Comments Dated May 1, 1992 from Walter Rolf, Montachusett Regional Planning Commission
on the April 1992 "Final Master Environmental Plan for Fort Devens," Argonne National
Laboratory.
4. Comments Dated May 7, 1992 from James P. Byrne, EPA Region I on the April 1992 "Final
Master Environmental Plan for Fort Devens," Argonne National Laboratory.
5. Comments Dated May 23, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the January 1994 "Preliminary Zone II Analysis
for the Production Wells at Fort Devens, MA, Draft Report", ETA Inc.

Responses to Comments

6. Response Dated June 29. 1992 from Carrol J. Howard, Fort Devens to the May 7, 1992
Comments from James P. Byrne, EPA Region I.

1.3 Site Inspection

Reports

1. "Final Task Order (Site Investigations) Work Plan," ABB Environmental Services. Inc.
(December 1992).
2. "Final Task Order (Site Investigations) Work Plan - Historic Gas Stations," ABB
Environmental Services, Inc. (December 1992).
3. "SI Data Packages - Army Environmental Center - Volume I," ABB Environmental Services,
Inc. (January 1993).
4. "SI Data Packages - Army Environmental Center - Volume II." ABB Environmental Services.
Inc. (January 1993).
5. "SI Data Package Meeting Notes for Groups 2 & 7 and Historic Gas Stations," ABB
Environmental Services, Inc. (April 1993).
6. "Final SI Report, Groups 2 & 7 and Historic Gas Stations, Volume I," ABB Environmental
Services, Inc. (May 1993).
7. "Final SI Report, Groups 2 & 7 and Historic Gas Stations, Volume II," ABB Environmental
Services, Inc. (May 1993).
8. "Final SI Report, Groups 2 & 7 and Historic Gas Stations, Volume III" ABB Environmental
Services, Inc. (May 1993) .
9. "Final SI Report, Groups 2 & 7 and Historic Gas Stations, Volume IV," ABB Environmental
Services, Inc. (May 1993).
10. "Final Supplemental Site Investigation Work Plan," ABB Environmental Services, Inc.
(August 1993).
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11. "Supplemental Site Investigation Data Package Groups 2 & 7 and Historic Gas Stations,"
ABB Environmental Services, Inc. (January 1994).
12. "Supplemental Site Investigation Data Package Meeting Notes Groups 2 & 7 and Historic
Gas Stations," ABB Environmental Services, Inc. (March 1994).
Missing 13. "Supplemental Sampling Plan for Study Area 42, Popping Furnace," OHM Remediation
Corporation (October 14, 1994).

Comments

14. Comments Dated January 11, 1993 from D. Lynne Chappell, Commonwealth of Massachusetts
Department of Environmental Protection on the December 1992 "Final Task Order (Site
Investigation) Work Plan." ABB Environmental Services, Inc.
15. Comments Dated January 12, 1993 from James P. Byrne, EPA Region I on the December 1992
"Final Task Order (Site Investigation) Work Plan," ABB Environmental Services, Inc.
and the December 1992 "Final Task, Order (Site Investigation) Work Plan - Historic Gas
Stations," ABB Environmental Services, Inc.
16. Comments Dated July 15, 1993) from James P. Byrne, EPA Region I on the May 1993 "Final
SI Report, Groups 2 & 7 and Historic Gas Stations." ABB Environmental Services, Inc.
17. Comments Dated July 9, 1993 and July 19, 1993 from D. Lynne Chappell, Commonwealth of
Massachusetts Department of Environmental Protection on the May 1993 "Final SI Report,
Groups 2 & 7 and Historic Gas Stations," ABB Environmental Services, Inc.
18. Comments Dated March 7, 1994 from Molly Elder, Commonwealth of Massachusetts Department
of Environmental Protection on the January 1994 "Supplemental Site Investigation Data
Package, Groups 2 & 7 and Historic Gas Stations," ABB Environmental Services, Inc.
19. Comments Dated March 23, 1994 from James P. Byrne, EPA Region I on the January 1994
"Supplemental Site Investigation Data Package, Groups 2 & 7 and Historic Gas Stations,"
ABB Environmental Services, Inc.
20. Comments Dated November 2, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the October 14, 1994 "Supplement Sampling Plan
for Study Area 42, Popping Furnace," OHM Remediation Corporation.

Responses to Comments

21. Responses Dated September 1993 from U.S. Army Environmental Center on the following
document: Final Site Investigation Report, Groups 2 & 7 and Historic Gas Stations,
dated May 1993.
22. Cross Reference: Responses Dated September 1993 from U.S. Army Environmental Center on
the following document: Draft Supplemental Site Investigation Work Plan, (Appendix M of
Final SI Report), dated May 1993. [These Responses are filed and cited as entry number
18 in the Responses to Comments section of this minor break].
23. Responses Dated September 1994 from U.S. Army Environmental Center on the Supplemental
Site Investigation Data Package, Fort Devens Groups 2 & 7 and Historic Gas Stations.

Comments to Responses to Comments

24. Comments Dated September 30, 1993 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the Responses to Comments Package dated
September 1993 from the U.S. Army Environmental Center.
25. Comments Dated November 27, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the Army Responses to Comments, Supplemental
Site Investigation Data Package, Groups 2, 7, and Historic Gas Stations, Fort Devens,
Ma.

2.0 Removal Response

2.2 Removal Response Reports

Reports

1. "Draft Final Closure Report Study Area 49, Fort Devens, Massachusetts," OHM Remediation
Services Corporation (October 28, 1994).
2. "Draft Final Closure Report Study Area 43D, Fort Devens, Massachusetts," OHM Remediation
Services Corporation (November 21, 1994).
3. "Draft Final Closure Report Study Area 56, Fort Devens, Massachusetts," OHM Remediation
Services Corporation (January 24, 1995).
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Comments
Comments Dated December 29, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the October 28, 1994 "Draft Final Closure
Report, Study Area 49, Fort Devens, Massachusetts," (OHM Remediation Services
Corporation).
Comments Dated January 6, 1995 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the November 21, 1994 "Draft Final Closure
Report, Study Area 43D, Fort Devens, Massachusetts," (OHM Remediation Services
Corporation).
Comments Dated March 17, 1995 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the January 24, 1995 "Draft Final Closure
Report, Study Area 56, Fort Devens, Massachusetts," OHM Remediation Services
Corporation.
2.9 Action Memoranda

Reports

1. "Final Contract Plans and Specifications Clean Out and Closure, Lake George Study Area
45 (SA 45)," ABB Environmental Services, Inc. (January 1994).
2. "Final Contract Design Plans and Specifications Contaminated Soil Removal, Various
Sites, Fort Devens, Massachusetts," ABB Environmental Services, Inc. (April 1994).
3. "Final Action Memoranda, Various Sites, Fort Devens, Massachusetts," ABB Environmental
Services, Inc. (June 1994).
4. "Addendum - Revision 2 for Final Contract Design Plans & Specifications Contaminated
Soil Removal, Various Sites, Fort Devens, Massachusetts," ABB Environmental Services,
Inc. (September 9, 1994).
5. "Addendum - Revision 3 for Final Contract Design Plan & Specifications Contaminated Soil
Removal, Various Sites, Fort Devens, Massachusetts," ABB Environmental Services, Inc.
(September 16, 1994).
6. "Final Addendum - Revisions 2 and for Final Contract Design Plan & Specifications
Contaminated Soil Removal, Various Sites, Fort Devens, Massachusetts," ABB Environmental
Services, Inc. (October 28, 1994).
7. "Draft Addendum - Revision 4 for Final Contract Design Plans & Specifications
Contaminated Soil Removal, Various Sites, Fort Devens, Massachusetts," ABB Environmental
Services, Inc. (March 17, 1995).

Comments

8. Comments Dated February 17, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the January 1994 "Draft Contract Design Plans
and Specifications Contaminated Soil Removal, Various Sites, Fort Devens,
Massachusetts," ABB Environmental Services, Inc.
9. Comments Dated May 5, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts Department
of Environmental Protection on the April 1994 "Draft Action Memoranda, Various Sites,
Fort Devens, Massachusetts," ABB Environmental Services, Inc.
10. Comments Dated May 19, 1994 from James P. Byrne, EPA Region I on the April 1994 "Draft
Action Memoranda, Various Sites, Fort Devens, Massachusetts," ABB Environmental
Services, Inc.
11. Comments Dated June 10, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the April 1994 "Final Contract Design Plans
and Specifications, Contaminated Soil Removal, Various Sites, Fort Devens,
Massachusetts," ABB Environmental Services, Inc.
12. Comments Dated August 11, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the June 1994 "Final Action Memoranda, Various
Sites, Fort Devens, Massachusetts," ABB Environmental Services, Inc.
13. Comments Dated August 16, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the June 10, 1994 "Addendum - Revision 1 for
Final Contract Design Plans & Specifications, Contaminated Soil Removal, Various Sties,
Fort Devens, Massachusetts (ABB Environmental Services, Inc.).
14. Comments Dated September 28, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the September 9, 1994
"Addendum - Revision 2 for Final Contract Design Plans and Specifications Contaminated
Soil Removal Various Sites, Fort Devens, Massachusetts," (ABB Environmental Services,
Inc.).
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15. Comments Dated December 20, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the October 28, 1994 "Final Addendum -
Revisions 2 and 3 for Final Contract Design Plans & Specifications, Contaminated Soil
Removal Various Sites, Fort Devens, Massachusetts," (ABB Environmental Services, Inc).

Responses to Comments

16. Responses Dated March 1994 from U.S. Army Environmental Center on the following
document: Draft Contract Design Plans and Specifications Contaminated Soil Removal,
Various Sites, Fort Devens, Massachusetts dated January 1994.
17. Responses Dated June 1994 from U.S. Army Environmental Center on the following document:
Draft Action Memoranda. Various Sites, Fort Devens, Massachusetts dated April 1994.
18. Responses Dated January 25, 1994 from U.S. Army Environmental Center on the following
document: "Draft Design Specifications and Plans Lake George Street Vehicle Wash Area
(Study Area 45).
19. Responses Dated September 9, 1994 from U.S. Army Environmental Center on the Addendum -
Revisions 2 Final Contract Design Plans & Specifications Contaminated Soil Removal
Various Sites, Fort Devens, Massachusetts.
20. Response Dated October 28, 1994 from U.S. Army Environmental Center on the Final
Addendum - Revisions 2 and 3 for Final Contract Design Plans & Specifications,
Contaminated Soil Removal. Various Sites, Fort Devens, Massachusetts.

3.0 Remedial Investigation (RI)

3.2 Sampling and Analysis Data

Reports

1. Cross Reference: "Method for Determining Background Concentrations - Inorganic Analytes
in Soil and Groundwater - Fort Devens," ABB Environmental Services, Inc. (January 20,
1993) [Filed and cited as entry number 1 in minor break 3.2 Sampling and Analysis Data
of the Fort Devens Group 1A Sites Administrative Record Index].
2. "Data Comparison Report, Group 2 & 7 Sites Through Round 1 Sampling," COM Federal
Programs Corporation (March 1993).
3. "Draft Quality Assurance Project Plan, Remedial Investigations, Groups 2 & 7 and South
Post Impact Area, Fort Devens, Massachusetts," Ecology and Environment, Inc. (June
1993).

3.4 Interim Deliverables

Reports

1. Cross Reference: "Final Ground Water Flow Model at Fort Devens," Engineering
Technologies Associates, Inc. (May 24, 1993) [Filed and cited as entry number 1 in minor
break 3.4 Interim Deliverables of the Fort Devens Group 1A Sites Administrative Record
Index].
2. "Final Projects Operations Plan - Volume I of III," ABB Environmental Services, Inc.
(December 1992).
3. "Final Projects Operations Plan - Volume II of III - Appendix A: Health and Safety
Plan," ABB Environmental Services, Inc. (December 1992).
4. "Final Projects Operations Plan - Volume III of III - Appendix B: Laboratory QA Plan;
Appendix C: USATHAMA-Certified Analytical Methods," ABB Environmental Services,
Inc. (December 1992).

Comments

5. Comments Dated January 12, 1993 from James P. Byrne, EPA Region I on the December 1992
"Final Projects Operations Plan," ABB Environmental Services, Inc.
6. Cross Reference: Comments Dated February 1, 1993 from James P. Byrne, USEPA Region I and
D. Lynne Chappell, Commonwealth of Massachusetts Department of Environmental Protection
on the October 30, 1992 "Draft Final Ground Water Flow Model at Fort Devens,"
Engineering Technologies Associates, Inc. [Filed and cited as entry number 2 in minor
break 3.4 Interim Deliverables of the Fort Devens Group 1A Sites Administrative Record
File Index].
7. Comments Dated February 17, 1993 from D. Lynne Chappell, Commonwealth of Massachusetts
Department of Environmental Protection on the December 1992 "Final Project Operations
Plan," ABB Environmental Services, Inc.
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3.5 Applicable or Relevant and Appropriate Requirements (ARARs)

Cross Reference: The following report (entries 1 and 2 are filed and cited as entries 1 and
2 in minor break 3.5 Applicable or Relevant and Appropriate Requirements (ARARs) of the Fort
Devens Groups 3, 5, & 6 Sites Administrative Record Index.

Reports

1. "Draft Applicable or Relevant and Appropriate Requirements (ARARs) for CERCLA Remedial
Actions," U.S. Army Toxic and Hazardous Materials Agency (June 1992).
2. "Draft Assessment of Location-Specific Applicable or Relevant and Appropriate
Requirements (ARARs) for Fort Devens, Massachusetts," U.S. Army Toxic and Hazardous
Materials Agency (September 1992).

3.7 Work Plans and Progress Reports

Reports

1. "Draft Task Order Work Plan Area of Contamination (AOC) 41, AOC 43G and 43J, Fort
Devens, Draft Remedial Investigation/Feasibility Study Work Plan, Groups 1 & 7 and
Historic Gas Stations," ABB Environmental Services, Inc. (May 1994).
2. Final Task Order Work Plan Area of Contamination (AOC) 41, AOC 43G, and AOC 43J, Fort
Devens, Final Remedial Investigations/Feasibility Study Work Plan, Groups 2, 7, and
Historic Gas Stations." ABB Environmental Services, Inc. (August 1994).
3. "Revised Final Task Order Work Plan Area of Contamination (AOC) 41, AOC 43G, and AOC
43J, Fort Devens, Revised Final Remedial Investigations/Feasibility Study Work Plan,
Groups 2, 7, and Historic Gas Stations," ABB Environmental Services, Inc. (October
1994).

Comments

4. Comments Dated July 06, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection the May 1994 "Draft Task Order Work Plan Area of
Contamination (AOC) 41, AOC 43G and 43J, Fort Devens, Draft Remedial Investigation/
Feasibility Study Work Plan, Groups 2 & 7 and Historic Gas Stations," ABB Environmental
Services, Inc.
5. Comments Dated October 19, 1994 from James P. Byrne, USEPA Region 1, on the Final RI/FS
Work Plan for AOCs 41, 43G, and 43J and the Response to Comments for this Document.
6. Comments Dated October 21, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the August 1994 "Final Task Order Work Plan,
Area of Contamination (AOC) 41, 43G, and AOC 43J.
7. Comments Dated December 15, 1994 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the Revised Final Remedial Investigation/
Feasibility Study, Revised Final Task Order Work Plans AOC 41, AOC 4iG, and AOC 43J.

Response to Comments

8. Responses Dated September 1994 from U.S. Army Environmental Center on the following
Document: Draft RI/FS Work Plans for Area of Contamination (AOC) 41, AOC 43G, and AOC
43J.

Comments to Responses to Comments

9. Cross Reference: Comments Dated October 19, 1994 from D.Lynne Welsh, Commonwealth of
Massachusetts Department of Environmental Protection on the Final RI/FS Work Plan for
AOCs 41, 43G and 43J and the Response to Comments for this document. [Filed and cited as
entry number 6 in the Comments section of this minor break].

4.0 Feasibility Study (FS)

4.7 Work Plans and Progress Reports

Reports

1. Cross-Reference: "Draft Task Order Work Plan Areas of Contamination (AOC) 41, AOC 43G
and 43J, Fort Devens, Draft Remedial Investigation/ Feasibility Study Work Plan, Groups
2 & 7 and Historic Gas Stations," ABB Environmental Services, Inc. (May 1994) [Filed and
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cited as entry number 1 in minor break 3.7 Work Plans and Progress Reports]
2. "Draft Work Plan Predesign Field Work and Landfill Study, Fort Devens, Massachusetts,"
ABB Environmental Services, Inc. (June 1994).

Comments

3. Cross Reference: Comments Dated July 6, 1994 from D. Lynne Welsh, Commonwealth of
Massachusetts Department of Environmental Protection the May 1994 "Draft Task Order
Work Plan Area of Contamination (AOC) 41, AOC 43G and 43J, Fort Devens, Draft Remedial
Investigation/Feasibility Study Work Plan, Groups 2 & 7 and Historic Gas Stations,"
ABB Environmental Services, Inc. (Filed and cited as entry number 2 in the minor break
3.7 Work Plans and Progress Reports].
5.0 Record of Decision (ROD)

5.4 Record of Decision

Reports
1. "No Further Action Decision Document Under CERCLA, Fort Devens Study Area 58, Buildings
2648 and 2650 Fuel Oil Spills," ABB Environmental Services, Inc. (January 1994).
2. "No Further Action Decision Document Under CERCLA, Fort Devens Study Area
43C,E,F,,K,L,M,P,Q,R, and S," ABB Environmental Services, Inc. (January 1994).
3. "No Further Action Decision Document Under CERCLA, Fort Devens Study Area 28, Fort Devens
Waste Explosives Detonation Range (Training Area 14)." ABB Environmental Services, Inc.
(January 1994).
4. "No Further Action Decision Document Under CERCLA, Decision Briefing, Fort Devens Study
Area 28, Fort Devens Waste Explosives Detonation Range (Training Area 14)," ABB
Environmental Services, Inc. (January 1994).
5. "Draft No Further Action Decision Document Under CERCLA, Study Area 13, Landfill No. 9,
Groups 2 & 7 and Historic Gas Stations, Fort Devens. Massachusetts," ABB Environmental
Services, Inc. (May 1994).
6. "Draft No Further Action Decision Document Under CERCLA, Study Area 12, Landfill No. 8,
Groups 2 & 7 and Historic Gas Stations, Fort Devens, Massachusetts," ABB Environmental
Services, Inc. (May 1994).
7. "Draft No Further Action Decision Document Under CERCLA, Study Area 14, Landfill No. 10,
Groups 2 & 7 and Historic Gas Stations, Fort Devens, Massachusetts," ABB
Environmental Services, Inc. (May 1994).
8. "Draft No Further Action Decision Document Under CERCLA, Study Area 43B Historic Gas
Station Sites, Groups 2 & 7 and Historic Gas Stations, Fort Devens, Massachusetts,"
ABB Environmental Services, Inc. (May 1994).
9. "Draft No Further Action Decision Document Under CERCLA, Study Area 43N, Historic Gas
Station Sites, Groups 2 & 7 and Historic Gas Stations, Fort Devens, Massachusetts,"
ABB Environmental Services, Inc. (May 1994) .
10. "No Further Action Decision Under CERCLA, Study Area 43B, Historic Gas Station Sites,
Fort Devens, Massachusetts," ABB Environmental Services, Inc. (January 1995).
11. "No Further Action Decision Under CERCLA, Study Area 43C, Historic Gas Station Sites,
Fort Devens, Massachusetts," ABB Environmental Services, Inc. (January 1995).
12. "No Further Action Decision Under CERCLA, Study Area 43E, Historic Gas Station Sites,
Fort Devens, Massachusetts," ABB Environmental Services, Inc. (January 1995).
13. "No Further Action Decision Under CERCLA, Study Area 43F, Historic Gas Station Sites,
Fort Devens, Massachusetts," ABB Environmental Services, Inc. (January 1995).
14. "No-Further Action Decision Under CERCLA, Study Area 43K, Historic Gas Station Sites,
Fort Devens, Massachusetts," ABB Environmental Services, Inc. (January 1995).
15. "No Further Action Decision Under CERCLA, Study Area 43L. Historic Gas Station Sites,
Fort Devens, Massachusetts," ABB Environmental Services, Inc. (January 1995).
16. "No Further Action Decision Under CERCLA, Study Area 43M, Historic Gas Station Sites,
Fort Devens, Massachusetts." ABB Environmental Services. Inc. (January 1995).
17. "No Further Action Decision Under CERCLA, Study Area 43N, Historic Gas Station Sites,
Fort Devens, Massachusetts." ABB Environmental Services, Inc. (January, 1995).
18. "No Further Action Decision Under CERCLA, Study Area 43P, Historic Gas Station Sites,
Fort Devens, Massachusetts," ABB Environmental Services, Inc. (January 1995).
19. "No Further Action Decision Under CERCLA, Study Area 43Q, Historic Gas Station Sites,
Fort Devens, Massachusetts." ABB Environmental Services, Inc. (January 1995).
20. "No Further Action Decision Under CERCLA, Study Area 43R, Historic Gas Station Sites,
Fort Devens, Massachusetts." ABB Environmental Services, Inc. (January 1995).
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21. "No Further Action Decision Under CERCLA Study Area 43S, Historic Gas Station Sites, Fort
Devens, Massachusetts." ABB Environmental Services, Inc. (January 1995).
22. "No Further Action Decision Under CERCLA, Study Area 14, Landfill No. 14, Fort Devens,
Massachusetts," ABB Environmental Services, Inc. (January 1995).
23. "No Further Action Decision Under CERCLA, Fort Devens Study Area 28, Waste Explosives
Detonation Range (Training Area 14)," ABB Environmental Services, Inc. (January 1995).
24. "No Further Action Decision Under CERCLA, Study Area 48, Building 202 Leaking Underground
Storage Tank Site, Fort Devens, Massachusetts," ABB Environmental Services, Inc.
(January 1995).

Comments

25. Comments Dated September 1993) from James P. Byrne, EPA Region I on the August 199-3)
"Draft Decision Document, Fort Devens Study Area 58, Buildings 2648 and 2650 Fuel Oil
Spills," ABB Environmental Services, Inc.
26. Comments Dated October 1, 1993 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the August 1993 "Draft Decision Document, Fort
Devens Study Area 58, Buildings 2648 and 2650 Fuel Oil Spill," ABB Environmental
Services, Inc.
27. Comments Dated September 30, 1994 from James P. Byrne. EPA Region I on the August 1993
"Draft Decision Document, Fort Devens Study Area 2-8, Waste Explosives Detonation Range
(Training Area 14)." ABB Environmental Services, Inc.
28. Comments Dated November 3, 1993 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection on the September 1993 "Draft Decision Document
Fort Devens Historic Gas Stations. Study Area 43C,E,F,K,L,M,P,Q,R, and S." ABB
Environmental Services, Inc.
29. Comments Dated November 17, 1993 from James P. Byrne on the September 1993) "Draft
Decision Document Fort Devens Historic Gas Stations, Study Area 43C,E,F,K,L,M, P,Q,R, and
S," ABB Environmental Services, Inc.
30. Comments Dated June 29, 1994 from D. Lynne Welsh. Commonwealth of Massachusetts
Department of Environmental Protection on the May 1994 "Draft No Further Action Decision'
Document Under CERCLA, Study Area 13, Landfill No. 9, Groups 2 & 7 and Historic Gas
Stations, Fort Devens, Massachusetts," ABB Environmental Services, Inc., "Draft No
Further Action Decision Document Under CERCLA Study Area 12. Landfill No. 8, Groups 2 & 7
and Historic Gas Stations, Fort Devens, Massachusetts," ABB Environmental Services. Inc.,
"Draft No Further Action Decision Document Under CERCLA, Study Area 14, Landfill No. 10,
Groups 2 & 7 and Historic Gas Stations, Fort Devens, Massachusetts," ABB Environmental
Services, Inc., "Draft No Further Action Decision Document Under CERCLA, Study Area 43B,
Historic Gas Station Sites, Groups 2 & 7 and Historic Gas Stations, Fort Devens,
Massachusetts," ABB Environmental Services, Inc., "Draft No Further Action Decision
Document Under CERCLA, Study Area 43N, Historic Gas Station Sites, Groups 2 & 7 and
Historic Gas Stations, Fort Devens, Massachusetts." ABB Environmental Services, Inc.
31. Comments Dated September 30, 1994 from James P. Byrne, EPA Region I on the August 1993
"Draft Decision Document, Fort Devens Study Area 28, Waste Explosives Detonation
Range (Training Area 14)," ABB Environmental Services, Inc.
32. Comments Dated June 30, 1994 from James P. Byrne, USEPA Region I on the No Further Action
Decision Under CERCLA Documents for Study Area 28 and 47.
33. Comments Dated March 17, 1995 from D. Lynne Welsh, Commonwealth of Massachusetts
Department of Environmental Protection.

Response to Comments

34. Responses Dated January 1995 from U.S. Army Environmental Center on the following
documents: Draft No Further Action Decision Under CERCLA SA 14. SA 43B and SA 43N -
Groups 2, 7, and Historic Gas Stations, Fort Devens. Massachusetts.
35. Responses Dated January 1995 from U.S. Army Environmental Center on the following
documents: Draft No Further Action Decision Under CERCLA SA 43C, E, F, L, M, P, Q, R, S -
Groups 2, 7, and Historic Gas Stations, Fort Devens, Massachusetts.
36. Responses Dated January 1995 from U.S. Army Environmental Center on the following
documents: Draft No Further Action Decision Under CERCLA SA 58 - Groups 2.7. and Historic
Gas Stations, Fort Devens, Massachusetts.
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10.0 Enforcement

10.16 Federal Facility Agreements

1. Cross Reference: "Final Federal Facility Agreement Under CERCLA Section 120," EPA Region
I and U.S. Department of the Army (November 15, 1991) with attached map [Filed and cited
as entry number 1 in minor break 10.16 Federal Facility Agreements of the Fort Devens
Group 1A Sites Administrative Record Index].

13.0 Community Relations

13.2 Community Relations Plans

Reports

1. Cross Reference: "Final Community Relations Plan," Ecology and Environment, Inc. (February
1992) [Filed and cited as entry number 1 in minor break 13-2 Community Relations Plans of
the Fort Devens Group 1A Sites Administrative Record Index].

Comments

2. Cross Reference: Letter from James P. Byrne, EPA Region I to F. Timothy Prior, Fort Devens
(March 19, 1992), concerning approval of the February 1992 "Final Community Relations
Plan," Ecology and Environment. Inc.

13.11 Technical Review Committee Documents

Cross-Reference: The following documents cited below as entries number 1 through 8 are filed and
cited as entries number 1 through 8 in minor break 13.11 Technical Review Committee Documents of
the Fort Devens Group 1A Sites Administrative Record.

1. Technical Review Committee Meeting Agenda and Summary (March 21, 1991).
2. Technical Review Committee Meeting Agenda and Summary (June 27,1991) .
3. Technical Review Committee Meeting Agenda and Summary (September 17, 1991).
4. Technical Review Committee Meeting Agenda and Summary (December 11, 1991).
5. Technical Review Committee Meeting Agenda and Summary (March 24, 1992).
6. Technical Review Committee Meeting Agenda and Summary (June 23, 1992).
7. Technical Review Committee Meeting Agenda and Summary (September 29, 1992).
8. Technical Review Committee Meeting Agenda and Summary (January 5, 1993).

17.0 Site Management Records

17.6 Site Management Plans

Cross-Reference: The following Reports, Comments, and Responses to Comments (entries 1 through 9)
are filed and cited in minor break 17.6 Site Management Records of the Groups 3, 5, & 6
Administrative Record Index unless otherwise noted below.

Reports

1. "Final Quality Assurance Project Plan," Ecology and Environment, Inc. (November 1991).
2. "General Management Procedures, Excavated Waste Site Soils, Fort Devens, Massachusetts," ABB
Environmental Services, Inc. (January 1994).

Comments

3. Cross Reference: Comments from James P. Byrne, EPA Region I on the November 1991 "Final Quality
Assurance Project Plan," Ecology and Environment, Inc. [These Comments are filed and cited as a
part of entry number 8 in the Responses to Comments section of this minor break].
4. Comments Dated December 16, 1993 from Molly J. Elder, Commonwealth of Massachusetts Department
of Environmental Protection on the November 1993 "Draft General Management Procedures.
Excavated Waste Site Soils. Fort Devens, Massachusetts." ABB Environmental Services, Inc.
5. Comments Dated December 27, 1993 from James P. Byrne. EPA Region I on the November 1993 "Draft
General Management Procedures. Excavated Waste Site Soils. Fort Devens, Massachusetts," ABB
Environmental Services. Inc. [Filed and cited as entry number 4 in minor break 4.4 Interim
Deliverables of the AOCs 44/52 Administrative Record Index.]
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6. Comments Dated March 11, 1994 from D. Lynne Welsh. Commonwealth of Massachusetts Department of
Environmental Protection on the January 1994 "General Management Procedures. Excavated Waste
Site Soils, Fort Devens, Massachusetts," ABB Environmental Services, Inc.

Responses to Comments

7. Cross-Reference: U.S. Army Environmental Center Responses to Comments on the following
documents: Feasibility Study Report, Biological Treatability Study Report; Feasability Study
Report - New Alternative 9; Draft General Management Procedures Excavated Waste Site Soils; and
Draft Siting Study Report, dated January 25, 1994. [These Responses to Comments are filed and
cited as a part of entry number 7 in the Responses to Comments section of minor break 4.4
Interim Deliverables of the AOCs 44/52 Administrative Record Index.]
8. Response from Fort Devens to Comments from James P. Byrne, EPA Region I on the November 1991
"Final Quality Assurance Project Plan." Ecology and Environment, Inc.
9. Cross-Reference: U.S. Army Environmental Center Responses to Comments for the following
documents: Final Feasibility Study Report; Draft Proposed Plan; Revised Draft Proposed Plan;
Draft Excavated Soils Management Plan; Final General Management Procedures Excavated Waste Site
Soils; and Biological Treatability Study Report, dated May 1994. [These Responses to Comments
are filed and cited as entry number 8 in the Responses to Comments section of minor break 4.4
Interim Deliverables of the AOCs 44/52 Administrative Record Index.]

17.9 Site Safety Plans

Cross Reference: The following documents (entries 1 through 3) are filed and cited in minor break 17.9
Site Safety Plans of the Fort Devens Group 1A Administrative Record File Index unless otherwise noted
below.

Reports

1. "Final Health and Safety Plan," Ecology and Environment, Inc. (November 1991).

Comments

2. Cross Reference: - Comments from James P. Byrne. EPA Region I on the November 1991 "Final
Health and Safety Plan," Ecology and Environment, Inc. [These Comments are filed and cited
as a part of entry number 8 in minor break 17.6 Site Management Plans of the Group 1A Sites
Administrative Record File Index).

Responses to Comments

3. Response from Fort Devens to Comments from James P. Byrne, EPA Region I on the November
1991 "Final Health and Safety Plan," Ecology and Environment, Inc.
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Section II

GUIDANCE DOCUMENTS

The following guidance documents were relied upon during the Fort Devens cleanup. These documents may be
reviewed, by appointment only, at the Environmental Management Office at Fort Devens, Massachusetts.

1. Occupational Safety and Health Administration (OSHA). Hazardous Waste Operation and Emergency
Response (Final Rule, 29 CFR Part 1910, Federal Register. Volume 54. Number 42) March 6, 1989.
2. USATHAMA. Geotechnical Reguirements for Drilling Monitoring Well, Data Acguisition, and Reports,
March 1987.
3. USATHAMA. IRDMIS User's Manual, Version 4.2, April 1991.
4. USATHAMA. USATHAMA Quality Assurance Program: PAM-41, January 1990.
5. USATHAMA. Draft Underground Storage Tank Removal Protocol - Fort Devens, Massachusetts, December 4,
1992.
6. U.S. Environmental Protection Agency. Guidance for Preparation of Combined Work/Quality Assurance
Project Plans for Environmental Monitoring: OWRS QA-1, May 1984.
7. U.S. Environmental Protection Agency. Office of Research and Development Interim Guidelines and
Specifications for Preparing Quality Assurance Project Plans: OAMS-005/80, 1983.
8. U.S. Environmental Protection Agency, Office of Emergency and Remedial Response, Interim-Final
Guidance for Conducting Remedial Investigations and Feasibility Studies Under CERCLA (OSWER Directive
9355.3-01, EPA/540/3-89/004, 1986.
9. U.S. Environmental Protection Agency. Test Methods for Evaluating Solid Waste: EPA SW-846 Third
Edition. September 1986.
10. U.S. Environmental Protection Agency. Office of Emergency and Remedial Response. Risk Assessment
Guidance for Superfund. Volume I. Human Health Evaluation Manual (Part A). (EPA/540/1-89/002), 1989.
11. U.S. Environmental Protection Agency. Hazardous Waste Management System; Identification and Listing
of Hazardous Waste: Toxicity Characteristic Revisions, (Final Rule. 40 CFR Part 261 et al., Federal
Register Part V), June 29, 1990.
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APPENDIX E - DECLARATION OF STATE CONCURRENCE
COMMONWEALTH OF MASSACHUSETTS
EXECUTIVE OFFICE OF ENVIRONMENTAL AFFAIRS
DEPARTMENT OF ENVIRONMENTAL PROTECTION
CENTRAL REGIONAL OFFICE
WILLIAM F. WELD
Governor

ARGEO PAUL CELLUCCI
Lt. Governor
TRUDY COXE
Secretary

DAVED B. STRUHS
Commissioner
October 10, 1996
Ms. Linda Murphy, Director
U.S. Environmental Protection Agency
Region I-JFK Federal Building
Boston, MA 02203

RE: Record of Decision; Areas of Contamination 43G and 43J
Devens, Massachusetts

Dear Ms. Murphy,

The Massachusetts Department of Environmental Protection (MADEP) has reviewed the above-referenced Record
of Decision (ROD) as recommended by the United States Army and the U.S. Environmental Protection Agency
(EPA) , Region I for the intrinsic bioremediation of Areas of Contamination (AOC) 43G and 43J at the
former Fort Devens. The MADEP has worked closely with the Army and EPA in the development of the
preferred alternative and herein concurs with the Army's choice of remedy.

The ROD covers two Historic Gas Stations that were identified in the Master Environmental Plan prepared
through the Army Installation Restoration Program. Based on past use, these areas were recognized as
potential sources of groundwater contamination and subseguently recommended for investigation. Both sites
have been through Site Investigations, Supplemental Site Investigations, Remedial Investigations and
Feasibility Studies. AOCs 43G and 431 and the properties immediately downgradient will be retained in
Army ownership as part of the Army Reserve Enclave.

The chosen remedy includes additional data collection during the remedial design phase of the intrinsic
bioremediation program, groundwater modeling of chemical fate and transport, installation of additional
groundwater monitoring wells, development of a long-term monitoring program designed to demonstrate
contaminant degradation, annual reporting, and five year project reviews. These oversight programs are
key to the success of this remedy.

MADEP's concurrence with this remedy is premised on the ability of oil and chemicals of potential concern
(CPCs) to be biologically and naturally attenuated before the contaminant plumes migrate off Army
property. An area located sufficiently inside the property boundary will be identified in the long-term
monitoring plan in which compliance will be determined, according to clean-up criteria stated in the ROD
that, at a minimum, will meet drinking water standards and be based on adeguate analytical parameters.

The MADEP would like to thank the US Army, particularly Jim Chambers, Fort Devens BRAG Environmental
Coordinator; and Jerry Keefe, EPA Remedial-Project Manager, for their efforts to ensure that the people
and the environment of the Commonwealth of Massachusetts are protected in the selection of the remedy for
these complex sites.

We look forward to continuing to work with the EPA and the Army during the implementation of the remedial
alternatives at these two sites and further clean-up activities on the other Devens sites. If you have
any guestions, please feel free to contact Christopher Knuth at (508) 767-2829 or Lynne Welsh at (508)
792-7651, ext. 3851.

Informational Repositories
Jim Chambers, Fort Devens BEG
Jim Byrne, EPA
Ron Ostrowski, Mass Land Bank
Jay Naparstek, MADEP
Rebecca Cutting, MADEP
Andy Cohen, MADEP, OGC, Boston
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APPENDIX F - GLOSSARY OF ACRONYMS AND ABBREVIATIONS
AAFES Army Air Force Exchange Service
AOC Area of Contamination
ARAR Applicable or Relevant and Appropriate Requirement
BETX benzene, ethylbenzene, toluene, and xylene
bgs below ground surface
BRAG Base Realignment and Closure Act
CAC Citizen's Advisory Committee
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
CFR Code of Federal Regulations
CMR Code of Massachusetts Regulations
CPC chemical of potential concern
CSF cancer slope factor
BBS Environmental Baseline Survey
FS Feasibility Study
GC gas chromatograph
HI Hazard Index
HQ Hazard Quotient
IAG Interagency Agreement
IRP Installation Restoration Program
MADEP Massachusetts Department of Environmental Protection
MCL Maximum Contaminant Level
MCP Massachusetts Contingency Plan
MEP Master Environmental Plan
mg/L milligrams per liter
MMCL Massachusetts Maximum Contaminant Level
NFA No Further Action
NPL National Priorities List
NCP National Contingency Plan
O&M Operation and Maintenance
ORP oxidation reduction potential
POL petroleum, oil, and lubricants
ppb parts per billion
PRE Preliminary Risk Evaluation
PRG Preliminary Remediation Goal
PVC polyvinyl chloride
RAB Restoration Advisory Board
RCRA Resource Conservation and Recovery Act
RI remedial investigation
SA Study Area
SARA Superfund Amendments and Reauthorization Act of 1986
SI Site Investigation
SSI Supplemental Site Investigation
SVE Soil Vapor Extraction
SVOC semivolatile organic compound
TOG total organic carbon
TPHC total petroleum hydrocarbon
TRC Technical Review Committee
TSS total suspended solids
Ig/g micrograms per gram
Ig/L micrograms per liter
USAEC U.S. Army Environmental Center
USATHAMA U.S. army Toxic and Hazardous Materials Agency
USEPA U.S. Environmental Protection Agency
UST underground storage tank
VOC volatile organic compound
WWTF wastewater treatment facility
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