Superfund Record of Decision Naval Weapons Station Earle (Site A) OU 3 Colts Neck NJ


                                    EPA/ROD/R02-98/142
                                    1998
EPA Superfund
     Record of Decision:
     NAVAL WEAPONS STATION EARLE (SITE A)
     EPA ID:  NJ0170022172
     OU03
     COLTS NECK, NJ
     09/29/1998

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EPA 541-R98-142

                            RECORD OF DECISION

                          OPERABLE UNIT 3 (OU-3)
                                 SITE 26

                        NAVAL WEAPONS STATION EARLE
                          Colts Neck, New Jersey

                             

                             Northern Division
                    Naval Facilities Engineering Command
                       Contract No. N62472-90-D-1298
                              Contract Task Order 279

                                AUGUST 1998

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DEPARTMENT OF THE NAVY
NAVAL WEAPONS STATION EARLE
201 HWY 34 SOUTH IN REPLY REFER TO
COLTS NECK, NEW JERSEY 07722-5001 5090
Ser 043/231
September 18, 1998

Ms. Jessica Mollin
Remedial Project Manager
United States Environmental Protection Agency
290 Broadway, 20th Floor
New York, New York 10007

Dear Ms. Mollin:

The enclosed "Record of Decision for Operable Unit 3 (OU-3), Site 26" has been signed by the Commanding
Officer of Naval Weapons Station Earle, Captain Robert M. Honey, and is enclosed for the signature of the
Regional Administrator of the U. S. Environmental Protection Agency.

This Record of Decision confirms the Navy's commitment to implement air sparging/soil vapor extraction
technology to recover solvent from groundwater at Site 26 (located adjacent to Naval Weapons Station Earle
Building GB-1), as well as reguisite groundwater monitoring.

If you reguire any further information regarding this document, please contact Mr. Gregory Goepfert,
Environmental Engineer, at (732) 866-2515.

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RECORD OF DECISION
NAVAL WEAPONS STATION EARLE
OPERABLE UNIT 3

TABLE OF CONTENTS

PART I - DECLARATION

I. SITE NAME AND LOCATION
II. STATEMENT OF BASIS AND PURPOSE
III. ASSESSMENT OF THE SITE
IV. DESCRIPTION OF THE SELECTED REMEDY
V. STATUTORY DETERMINATION

PART II - DECISION SUMMARY

I. SITE NAME, LOCATION, AND DESCRIPTION
II. SITE HISTORY AND ENFORCEMENT ACTIVITY
III. HIGHLIGHTS OF COMMUNITY PARTICIPATION
IV. SCOPE AND ROLE OF OPERABLE UNIT 3
V. SUMMARY OF SITE CHARACTERISTICS
VI. SUMMARY OF SITE RISKS
VII. REMEDIAL ACTION OBJECTIVES
VIII. DESCRIPTION OF REMEDIAL ACTION ALTERNATIVES
IX. SUMMARY OF COOPERATIVE ANALYSIS OF ALTERNATIVES
X. THE SELECTED REMEDY
XI. STATUTORY DETERMINATIONS
XII. DOCUMENTATION OF SIGNIFICANT CHANGES

PART III - RESPONSIVENESS SUMMARY
I. OVERVIEW
II. BACKGROUND ON COMMUNITY INVOLVEMENT
III. SUMMARY OF MAJOR QUESTIONS AND COMMENTS
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LIST OF TABLES
TABLE
DESCRIPTION
1
2
3
4
5
6
7
8
9
10
11
12
13
Comparison of Site-Related Metals in Groundwater to Background
Site 26 Groundwater Exceeding ARARs
Summary of Estimated RME Cancer Risks and Noncarcinogenic Hazard Indices
Summary of Central Tendency Cancer Risks and Noncarcinogenic Hazard Indices
Screening of Remedial Alternatives
Comparative Analysis of Remedial Action Alternatives
Potential Federal Chemical-Specific ARARs and TBCs
Potential State Chemical-Specific ARARs and TBCs
Potential Federal Location-Specific ARARs and TBCs
Potential State Location-Specific ARARs and TBCs
Potential Federal Action-Specific ARARs and TBCs
Potential State Action-Specific ARARs and TBCs
Groundwater Preliminary Remediation Goals

LIST OF FIGURES
FIGURE
DESCRIPTION
Regional Site Map
Mainside Site Locations
Site 26 - Explosive "D" Washout Area
Groundwater Contour Map - Site 26 (August 7, 1995)
Groundwater Contour Map - Site 26 (October 17, 1995)
Concentrations above Screening Levels - Groundwater
LIST OF APPENDICES
Appendix A Terms Used In the Record of Decision
Appendix B Attendance List 1998 Public Meeting
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RECORD OF DECISION
NAVAL WEAPONS STATION EARLE
OPERABLE UNIT 3 (SITE 26)

PART I - DECLARATION

I. SITE NAME AND LOCATION

Naval Weapons Station Earle
Colts Neck, Monmouth County, New Jersey

II. STATEMENT OF BASIS AND PURPOSE

This Record of Decision (ROD) presents the remedial action alternative selected for Operable Unit 3 (OU-
3) to address soil and groundwater contamination at the Naval Weapons Station (NWS) Earle Site, located
in Colts Neck, New Jersey. OU-3 includes the portion of Site 26 comprised of the former process leach tank
connected to Building GB-1 and associated soil and groundwater contamination apparently emanating from the
tank.

This remedial action decision is in accordance with the Comprehensive Environmental Response, Compensation,
and Liability Act of 1980 (CERCLA) as amended by the Superfund Amendments and Reauthorization Act of 1986
(SARA) and the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). This decision document
explains the factual and legal basis for selecting the remedial action and is based on the Administrative
Record for OU-3. Reports and other information used in the remedy selection process are part of the
Administrative Record file for OU-3, which is available at the Monmouth County Library, Eastern Branch, Route
35, Shrewsbury, New Jersey.

The New Jersey Department of Environmental Protection (NJDEP) has commented on the selected remedy, and their
comments have been incorporated into this ROD. A review of the public response to the Proposed Plan is
included in the Responsiveness Summary (Part III) of this decision document.

III. ASSESSMENT OF THE SITE

Actual or threatened releases of hazardous substances from OU-3, as discussed in Section VI (Summary of Site
Risks) of this ROD, if not addressed by implementing the remedial action selected in this ROD, may present an
imminent and substantial endangerment to public health, welfare, or the environment.

IV. DESCRIPTION OF THE SELECTED REMEDY

The Department of the Navy (Navy) and the United States Environmental Protection Agency (EPA) , in
consultation with NJDEP, have selected the following remedy for OU-3: air sparging with soil vapor
extraction, source removal, institutional controls, and long-term monitoring. The remedy addresses
contaminated source materials (the process leach tank and associated soils which have been excavated and
disposed) and contaminated groundwater in the vicinity downgradient of the process leach tank. The selected
remedy for OU-3 consists of the following major components:

1. Excavate and dispose of the process leach tank and adjacent contaminated soils.

2. Treat residual soil and groundwater contamination through the use of air sparging/vapor extraction to
remove the larger portion of solvent compounds present to the physically limiting endpoint, followed
by monitored natural attenuation and periodic reviews of progress.

3. Establish a Classification Exception Area (CEA) immediately adjacent to Site 26 to bar the use of
groundwater during the remediation period.

4. Provide long-term periodic groundwater monitoring.
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While the remedial action objective (RAO) for groundwater protection would not be immediately achieved,
risks would be reduced in relation to background by removal of source materials (the process leach tank
and associated soils) and initiation of active remediation of contaminants in soil and groundwater using air
sparging/soil vapor extraction and continued monitoring to evaluate contaminant trends. Preliminary
remediation goals (largely based on NJDEP Groundwater Quality Standards) are presented in Table 13. Long-term
periodic monitoring and analysis will be undertaken determine when the RAO is achieved.

V. STATUTORY DETERMINATION

The selected remedy is protective of human health and the environment and is cost effective. The Navy
and EPA believe that the selected remedy will comply with all federal and state reguirements that are
legally applicable or relevant and appropriate to the remedial action. The selected remedy utilizes a
permanent solution to the maximum extent practicable.

Because this remedy will result in hazardous substances remaining on the site above health-based levels,
a review by the Navy, EPA, and NJDEP will be conducted within 5 years after initiation of the remedial
action to ensure that the remedy continues to provide adeguate protection of human health and the
environment.

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RECORD OF DECISION
NAVAL WEAPONS STATION EARLE
OPERABLE UNIT 3
SITE 26

PART II - DECISION SUMMARY

I. SITE NAME, LOCATION, AND DESCRIPTION

A. General

NWS Earle is located in Monmouth County, New Jersey, approximately 47 miles south of New York City. The
station consists of two areas, the 10,248-acre Main Base (Mainside area), located inland, and the 706-acre
Waterfront area (Figure 1). The two areas are connected by a Navy-controlled right-of-way.

The facility was commissioned in 1943, and its primary mission is to supply ammunition to the naval fleet. An
estimated 2,500 people either work or live at the NWS Earle station.

The Mainside area is located approximately 10 miles inland from the Atlantic Ocean at Sandy Hook Bay in Colts
Neck Township, which has a population of approximately 6,500 people. The surrounding area includes
agricultural land, vacant land, and low-density housing. The Mainside area consists of a large, undeveloped
portion associated with ordnance operations, production, and storage; this portion is encumbered by explosive
safety guantity distance arcs. Other land use in the Mainside area consists of residences, offices,
workshops, warehouses, recreational space, open space, and undeveloped land. The Waterfront area is located
adjacent to Sandy Hook Bay in Middletown Township, which has a population of approximately 68,200 people. The
Mainside and Waterfront areas are connected by a narrow strip of land that serves as a government-controlled
right of way containing a road and railroad.

Operable Unit 3 (OU-3) includes the portion of Site 26 comprised of the former process leach tank connected
to Building GB-1 and associated soil and groundwater apparently emanating from the tank. OU-3 is located in
the Mainside area (Figure 2). A brief description of Site 26 follows.

B. Site 26: Explosive "D" Washout Area

Site 26 is situated at the intersection of Macassar and Midway Roads (Figure 3). Two railway lines adjacent
to the site run toward the northeast. The ground surface at the site is relatively flat, approximately 150
feet above mean sea level (MSL)

A percolation pit in the center of the site measures approximately 30 feet in diameter and 10 feet in depth.
A tile-lined open pipe runs from Building GB-1 to the percolation pit. A process leaching system north of the
western end of Building GB-1, thought to consist of a grease trap and a cesspool-type leach tank, was used
for process waste disposal.

For one year in the late 1960s, the site was used for the removal and recovery of ammonium picrate (known as
explosive D) from artillery shells. The water-soluble explosive was removed from the shells by a hot water
wash. The resulting solution flowed into a cooling/settling tank inside the building. Upon cooling, the
ammonium picrate precipitated and was collected for reuse or disposal. Overflow from the settling tank flowed
into the tile-lined open pipe to the percolation pit.

GB-1 reportedly was used for the reconditioning of munition casings/shells. Solvents were used in the
reconditioning process. Spent solvents and wash waters were discarded into an unknown receptacle, possibly a
collection tray at the formerly used paint spray booth, which drained to the process leaching system. The
GB-1 process leaching system appears to have been used for the disposal of trichloroethene (TCE),
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1,2-dichloroethene (1,2-DCE), or related compounds.

II. SITE HISTORY AND ENFORCEMENT ACTIVITY

Potential hazardous substance releases at Site 26 were addressed in an Initial Assessment Study (IAS) in
1982, a Site Inspection Study (SI) in 1986, and a Phase I RI in 1993. These were preliminary investigations
to determine the number of sources, compile histories of waste-handling and disposal practices at the site,
and acguire data on the types of contaminants present and potential human health and/or environmental
receptors. RI investigations at Site 26 included the installation and sampling of monitoring wells and
collection and analysis of surface soils.
In 1990, NWS Earle was placed on the National Priorities List (NPL). This list includes sites where
uncontrolled hazardous substance releases may potentially present serious threats to human health and the
environment.

Site 26 was subseguently addressed by Phase II RI activities to determine the nature and extent of
contamination. Activities included a soil gas survey at 68 locations, installation and sampling of
groundwater monitoring wells, soil sampling, "direct-push" groundwater sampling with on-site laboratory
analysis, and cone penetrometer studies to delineate subsurface soil stratigraphy. The Phase II RI was
initiated in 1995 and completed in 1996.

The results of the RI were used as the basis for performing a feasibility study (FS) of potential remedial
alternatives. The Navy and EPA, in consultation with NJDEP, developed the proposed remedial action plan
(Proposed Plan). The Proposed Plan is the basis for the selected remedial alternative presented in this ROD
and is based on the alternatives developed during the FS.

III. HIGHLIGHTS OF COMMUNITY PARTICIPATION

The documents that the Navy and EPA used to develop, evaluate, and select a remedial alternative for OU-3
(the RI, FS, Proposed Plan, and community input summaries) have been maintained at the Monmouth County
Library (Eastern Branch), Route 35, Shrewsbury, New Jersey.

The FS report, Proposed Plan, and other documents related to OU-3 were released to the public on December 19,
1997. The notice of availability of these documents was published in the Asbury Park Press on January 3, and
January 4, 1998. A public comment period was held from December 19, 1997 to January 30, 1998.

A public meeting was held during the public comment period on January 22, 1998. At this meeting,
representatives from the Navy and EPA were available to answer guestions about OU-3 and the remedial
altenatives under consideration. Results of the public comment period are included in the Responsiveness
Summary, which is Part III of this ROD.

IV. SCOPE AND ROLE OF RESPONSE ACTION FOR OPERABLE UNIT 3

The Department of the Navy completed an RI, FS, and Proposed Plan for OU-3, addressing contamination
associated with Site 26 at NWS Earle. These studies showed that soil contamination was evident in the
immediate vicinity of the process leach tank. Groundwater contamination was also evident downgradient of the
process leach tank. The final remedial action to address site contamination at Site 26 is described in this
document.

V. SUMMARY OF SITE CHARACTERISTICS

A. General

NWS Earle is located in the coastal lowlands of Monmouth County, New Jersey, within the Atlantic Coastal
Plain Physiographic Province. The Mainside area, which includes OU-3, lies in the outer Coastal Plain,
approximately 10 miles inland from the Atlantic Ocean. The Mainside area is relatively flat, with elevations
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ranging from approximately 100 to 300 feet above mean sea level (MSL). The most significant topographic
relief within the Mainside area is Hominy Hills, a northeast-southwest-trending group of low hills located
near the center of the station.

The rivers and streams draining NWS Earle ultimately discharge to the Atlantic Ocean, which is approximately
9 or 10 miles east of the Mainside area. The headwaters and drainage basins of three major Coastal Plain
rivers (Swimming, Manasguan, and Shark) originate on the Mainside area. The northern half of Mainside is in
the drainage basin of the Swimming River, and tributaries include Mine Brook, Hockhockson Brook, and Pine
Brook. The southwestern portion of the Mainside drains to the Manasguan River via either Marsh Bog Brook or
Mingamahone Brook. The southeastern corner of the Mainside drains to the Shark River. Both the Swimming River
and the Shark River supply water to reservoirs used for public water supplies.

NWS Earle is situated in the Coastal Plain Physiographic Province of New Jersey. The New Jersey Coastal Plain
is a seaward-dipping wedge of unconsolidated Cretaceous to Quaternary sediments that were deposited on a
pre-Cretaceous basement-bedrock complex. The Coastal Plain sediments are primarily composed of clay, silt,
sand, and gravel and were deposited in continental, coastal, and marine environments. The sediments generally
strike northeast-southwest and dip to the southeast at a rate of 10 to 60 feet per mile. The approximate
thickness of these sediments beneath NWS Earle is 900 feet. The pre-Cretaceous complex consists mainly of
PreCambrian and lower Paleozoic crystalline rocks and metamorphic schists and gneisses. The Cretaceous to
Miocene Coastal Plain Formations are either exposed at the surface or subcrop in a banded pattern that
roughly parallels the shoreline. The outcrop pattern is caused by the erosion truncation of the dipping
sedimentary wedge. Where these formations are not exposed, they are covered by essentially flat-lying
post-Miocene surficial deposits.

Groundwater classification areas were established in New Jersey under New Jersey Department of Environmental
Projection (NJDEP) Water Technical Programs Groundwater Quality Standards in New Jersey Administrative Code
(N.J.A.C.) 7:9-6. The Mainside area is located in the Class II-A: Groundwater Supporting Potable Water Supply
area. Class II-A includes those areas where groundwater is an existing source of potable water with
conventional water supply treatment or is a potential source of potable water. In the Mainside area, in
general, the deeper aguifers are used for public water supplies and the shallower aguifers are used for
domestic supplies.

OU-3 is situated in the recharge area of the Kirkwood-Cohansey aguifer system. The Kirkwood-Cohansey aguifer
system is a source of water in Monmouth County and is composed of the generally unconfined sediments of the
Cohansey Sand and Kirkwood Formation. The Kirkwood-Cohansey aguifer system has been reported in previous
investigations as being used for residential wells in the Mainside area. Along the coast, this aguifer system
is underlain by thick diatomaceous clay beds of the Kirkwood Formation.

All facilities located in the Mainside Administration area are connected to a public water supply (New
Jersey American Water Company). Building GB-1 is connected to the public water supply. Water for the public
supply network comes from surface water intakes, reservoirs, and deep wells. No public water supply wells or
surface water intakes are located on the NWS Earle facility. A combination of private wells and public water
supply from the New Jersey American Water Company serves businesses and residences in areas surrounding the
Mainside facilities. There are a number of private wells located within a 1-mile radius of NWS Earle and
several within the NWS Earle boundaries. The majority of these wells are used for potable supplies; previous
testing for drinking water parameters indicates these wells have not been adversely impacted.

There is a rich diversity of ecological systems and habitats at NWS Earle. Knieskern's beaked-rush
(Rynchospora knieskernii), a sedge species on the federal endangered list, has been seen on the station, and
some species on the New Jersey endangered list, such as the swamp pink (Helonias bullata), may be present. An
osprey has visited Mainside and may nest in another area at NWS Earle. The Mingamahone Brook supports bog
turtles downstream of the Mainside area and provides an appropriate habitat for them at the Mainside area.

B. Surface Water Hydrology

Site 26 is surrounded by wooded upland areas. The upland areas are dominated by pitch pine, blackjack oak,
blueberry, and Clethra sp. NJDEP Geographic Information System data initially indicated the presence of
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wetlands where the wooded upland areas are located. However, on-site inspection revealed that no wetlands are
present in the area. Soils in this area contain no evidence of saturation, no wetland hydrology is present,
and no streams or watercourses exist near the site.

The closest wetlands are located approximately 300 yards to the northwest. The East Branch of Mingamahone
Brook is located approximately 300 yards southwest of Site 26, and the site is in the Mingamahone Brook
watershed. Depth to groundwater ranges approximately from 10 to 14 feet below ground surface at Site 26.

C. Geology

Regional mapping places Site 26 in the outcrop area of the Kirkwood Formation; upland gravel may be present
at the site. The upland gravel has a maximum thickness of 10 feet, and the Kirkwood Formation ranges between
60 to 100 feet in thickness. The soil borings are no more than 24 feet deep and the cone penetrometer (CPT)
lithologic profile locations are no more than 100 feet deep. The lithology of the sediments encountered in
the on-site borings generally agrees with the published description of the upland gravel and the Kirkwood
Formation. In general, the borings encountered light yellowish-brown sand and gravel (probably representative
of the upland gravel) and brownish-yellow, brown and gray, fine- to medium-grained and medium- to
coarse-grained sand (probably representative of the Kirkwood Formation). Based on CPT lithologic profiling,
the upper approximate 25-foot section penetrated was a sand. Silty clay and clayey silt was penetrated from
approximately 25 to 45 feet and sand was penetrated from approximately 45 to 70 feet. A clayey silt was
penetrated from approximately 80 to 87 feet in one of the locations.

D. Hydrogeology

Groundwater in the Kirkwood aguifer beneath the site occurs under unconfined conditions. Groundwater contour
maps are presented in Figure 4 (August 1995 levels) and Figure 5 (October 1995 levels). The direction of
shallow groundwater flow in the aguifer, as indicated by both the August and October groundwater
measurements, is toward the southwest. There does not appear to be a significant seasonal variation in
groundwater flow direction.

Based on boring log descriptions, the wells are screened in the Kirkwood Formation. The hydraulic
conductivity's calculated for MW26-01, MW26-03, and MW26-04 are 3.85 x 10 -4 cm/sec (1.09 ft/day), 1.92 x 10
-3 cm/sec (5.44 ft/day), and 7.09 x 10 -4 cm/sec (2.01 ft/day), respectively.

Based on pore pressure plots, the water table was encountered at approximately 10 feet and a lower water
bearing zone was encountered at approximately 43 feet, bgs. The clayey siltey zone penetrated between
approximately 25 and 45 feet, bgs shows a sharp rise in pre-pressure, indicating this zone probably serves as
a semi-confining layer. Two pieces of evidence corroborate the findings of the cone penetrometer pore
pressure plots, confirming the presence of the semi-confining layer. Efforts to obtain groundwater samples
using the direct-push sampler from within the clay and silt zone yielded no water, and the tool screen was
found to be smeared with a plastic, clayey soil after attempts to obtain groundwater samples from the clay
and silt zone. This indicates the possibility of clay soils. Also, the vertical distribution of chlorinated
compounds detected in groundwater samples indicated contaminant concentrations orders of magnitude lower
below the postulated clay layer than above it, indicating that the clay layer is acting as an aguitard.

E. Nature and Extent of Contamination

1. IAS and SI Results

Groundwater was analyzed for picric acid (the form of ammonium picrate found in groundwater) and pH. Picric
acid was not detected and pH was within expected levels.

2. Phase I Remedial Investigation
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Lead was detected at levels greater than background but below screening guidance levels in soil samples
collected from the percolation pit. All other metals were within normal background ranges. Picric acid (the
ammonium picrate analogue in soils) was detected in one sample. No other explosive compounds were detected.

Groundwater samples from all Site 26 wells were collected and analyzed for Target Compound List/Target
Analyte List (TCL/TAL) analytes and explosive compounds. TCE was detected in one sample (MW26-01) at elevated
levels (660 ug/L). The NJ groundwater groundwater guality standard is one ug/L. Other volatile organic
compounds (VOCs), such as dichloroethenes (related to TCE as impurities or breakdown products), were also
present. The source of TCE was speculated to be associated with the process leaching system of Building GB-1.
Low concentrations of several explosive compounds were detected in samples from wells MW26-01 and MW26-04.

3. Phase II Remedial Investigation

Natural background levels of metals in local soils and groundwater were determined during the RI using
samples obtained from locations chosen as being isolated from former or present industrial or military
operations. In general, background sample locations were hydraulically upgradient or far removed from
potential sources of contamination. In order to compare site-related groundwater metals concentrations found
in a specific geologic formation to naturally occurring (background) levels found in the similar distinct
geologic formation, some existing facility monitoring well sample results were selected for use as
"background." All monitoring wells used in the calculation of background concentrations were deemed to have
been installed in "background" locations (upgradient of RI sites). The Navy, EPA, and NJDEP collaborated in
the selection of all background sample locations. The process of background concentration
determination and statistical evaluation is presented in Section 31 of the RI report. Table 1 summarizes the
range of background metals concentrations found in groundwater versus the range of concentrations found on
site.

Concentrations of most metals in site-related subsurface soil samples were within the same ranges as
background samples. Antimony was detected at low levels, near the instrument detection limit, in two
site-related subsurface soil samples but was not found in background samples. Barium was detected in one
site-related sample at levels greater than the concentration range associated with background samples but
below the corresponding regulatory screening guidance level.

In soil borings taken near the process leach tank, TCE (up to 74.0 ug/kg) and 1,2-dichloroethene (total) (up
to 140 ug/kg) were found at concentrations below the New Jersey Impact to Groundwater soil criteria for TCE
(1,000 ug/kg) and for 1,2-dichloroethene (trans - 50,000 ug/kg, and cis- 1,000 ug/kg).

Groundwater samples were collected from monitoring wells and by direct-push groundwater sampling methods
across Site 26. TCE, 1,2-DCE, and related compounds were encountered at significant concentrations in a wide
plume (approximately 350 feet by 130 feet) of contaminated groundwater southwest of Building GB-1. Subsurface
soil stratigraphy studies indicate the presence of a 15-feet-thick clay layer at a depth of approximately 25
to 40 feet below Site 26. Based on vertical profile sampling, the semi-confining clay layer appears to have
limited the vertical migration of TCE and related compounds.

Figure 6 depicts the location and concentration of compounds that exceeded applicable or relevant and
appropriate reguirements (ARARs) and other guidance to be considered (TBCs). The type of contaminants
detected and the configuration of the plume implicate the process leach tank as the source of groundwater
contamination. Table 2 summarizes the results of samples taken from groundwater compared to applicable
standards.
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TABIiE 1
COMPARISON OF SITE-RELATED METALS CONCENTRATION IN GROUNDWATER
TO BACKGROUND CONCENTRATIONS - SITE 26
NWS EARLE, COLTS NECK, NEW JERSEY
(Ig/L)
SUBSTANCE
BACKGROUND SITE-RELATED
FREQUENCY OF RANGE OF AVERAGE FREQUENCY OF RANGE OF AVERAGE
DETECTION POSITIVE CONCENTRATION DETECTION POSITIVE DETECTION CONCENTRATION
DETECTION
ALUMINUM
BARIUM
CADMIUM
CALCIUM
CHROMIUM
COBALT
COPPER
IRON
LEAD
MAGNESIUM
MANGANESE
MERCURY
NICKEL
POTASSIUM
SILVER
SODIUM
VANADIUM
ZINC
11/11
11/11
5/11
11/11
9/11
6/11
9/11
11/11
3/11
11/11
11/11
11/11
10/11
11/11
NOT DETECTED
11/11
10/11
6/9
287-7870
2.6-518
0.6-1.9
506-17200
1.3-43.5
0.7-10.1
0.79-13.5
153-7690
2.1-3
273-27400
3.3-65
0.005-0.12
0.81-25.5
350-3245
-
1850-11650
0.69-42.25
3.7-348
2549
114.80
0.61
4154
14.68
2.03
3.27
2099
1.22
4225
23.09
0.06
5.99
1406
0.47
4225
8.24
89.31
6/6
6/6
4/6
6/6
3/6
5/6
6/6
6/6
1/6
6/6
6/6
6/6
2/6
6/6
1/6
6/6
3/6
5/5
328-927
13.2-518
0.42-4.4
3540-17800
1.2-1.4
0.92-5.8
0.81-13.8
90.8-4740
2.6-2.6
636-2170
3.3-155
0.012-0.11
0.81-1
362-3640
3.3-3.3
2360-12500
0.81-1.6
100-326
539.33
267.78
1.04
8440
0.89
2.69
6.22
1172
1.06
1416
62.23
0.05
0.55
1385
0.94
4875
0.71
242.40

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Concentrations of most metals in site-related groundwater samples were within ranges similar to background
samples. Zinc was detected in four site-related groundwater samples at levels greater than the concentration
range associated with background samples. Barium was found at elevated levels in two samples, and cadmium and
silver were detected in one sample at levels greater than background ranges. However, soil sampling results
show no evidence of a source area of these contaminants, there is no evidence that these metals were used at
significant concentrations or disposed of at the site, detections of metals in groundwater were sporadic over
time and by location, and the risk assessment did not show these compounds to be the risk drivers.

Explosives were analyzed for but not detected in groundwater samples collected at Site 26, indicating that
the one low level of picric acid found in soil during Phase I investigations (1992-1993) had no impact on
groundwater and most likely was an isolated occurrence.

VI. SUMMARY OF SITE RISKS

As part of the Phase II RI, a human health risk assessment and ecological risk screening were performed at
OU-3. A four-step process was utilized to assess site-related human health risks for a reasonable maximum
exposure scenario Hazard Identification identifies the contaminants of concern at the site based on several
factors such as toxicity, freguency of occurrence, and concentration. Exposure Assessment estimates the
magnitude of actual and/or potential human exposures, the freguency and duration of these exposures, and the
pathways (e.g., ingesting contaminated well-water) by which humans are potentially exposed. Toxicity
Assessment determines the types of adverse health affects associated with chemical exposures, and the
relationship between the magnitude of exposure (dose) and severity of adverse effects (response). Risk
Characterization summarizes and combines outputs of the exposure and toxicity assessments to provide a
guantitative assessment of site-related risks and includes a discussion of site-specific uncertainties
associated with the site such as actual receptor pathways, and receptor activity patterns.

A. Human Health Risks

The human health risk assessment estimated the potential risks to human health posed by exposure to
contaminated groundwater and subsurface soils at Site 26. To assess these risks, the exposure scenarios
listed below were assumed:

• Ingestion of groundwater as a drinking water source.

• Inhalation of contaminants in groundwater (i.e., volatile compounds emitted during
showering).

• Dermal exposure to contaminants in groundwater (i.e., showering, hand washing, bathing).

• Dermal contact from contaminated soils.

• Inhalation of contaminants in soil (i.e., fugitive dusts).

• Incidental ingestion of contaminated soils.

A current industrial employee is an adult who currently works at NWS Earle. This receptor is currently
potentially exposed via ingestion of, dermal contact with, and inhalation of compounds in surface soil while
at work.

A future industrial employee is an adult who is assumed to work at NWS Earle in the future. This receptor is
potentially exposed via ingestion of compounds in subsurface soil (as future surface soil) and groundwater,
dermal contact with compounds in subsurface soil (as future surface soil) and groundwater (hand
washing/showering); and inhalation of compounds in subsurface soil (as future surface soil) while at work.

A future resident is a person who will live in a residence at or near NWS Earle in a hypothetical future
scenario. This receptor is assumed to reside for 30 years (six years as a child and 24 years as an adult).
This receptor is potentially exposed via ingestion of compounds in surface soil, subsurface soil (as future
-------
surface soil), and groundwater, dermal contact with compounds in surface soil, subsurface soil (as future
surface soil), and groundwater (child during bathing; adult during showering); inhalation of compounds in
airborne dust from surface soil and subsurface soil (as future surface soil); and inhalabon of compounds in
groundwater vapors during showering (adult only, 24-year exposure).

A future residential child (ages six to 12) will live in a residence at or near NWS Earle. This hypothetical
receptor will wade in surface water and stream sediments present. This receptor is potentially exposed via
ingestion to and by dermal contact with compounds in sediment and surface water.

These scenarios were applied to various site use categories, including future industrial use and future
lifetime resident.

Potential human health risks were categorized as carcinogenic or noncarcinogenic. A hypothetical carcinogenic
risk increase from exposure should ideally fall below a risk range of 1 x 10 -6 (an increase of one case of
cancer for one million people exposed) to 1 x 10 -4 (an increase of one case of cancer per 10,000 people
exposed).

Noncarcinogenic risks were estimated using Hazard Indices (HI), where an HI exceeding one is considered an
unacceptable health risk. Hazard Indices are the summation of individual chemical and pathway Hazard
Quotients (HQ). An HQ is calculated as the lifetime average daily dose compared to (divided by) the Reference
Dose (RfD) that is an estimate of a daily exposure level for the human population, including sensitive
populations, that is likely to be without appreciable risk or harmful effects over a lifetime. These
estimated noncarcinogenic risks are based on a continuous exposure to contaminants for the defined lifetime
exposure of the receptor, however, detrimental health effects are often reversed if contact is removed.

In addition, results were compared to applicable federal and/or state standards such as federal Maximum
Contaminant Levels (MCLs) for drinking water, NJDEP Groundwater Quality Standards (GWQS), or other published
lists of reference values.

A human health risk characterization was derived for OU-3 from the risk assessment. Highlights of the risk
assessment are provided below. The risk assessment was performed according to EPA guidance. Details such as
assumptions used in certain calculations or uncertainty discussions can be obtained on the general procedures
section (Section 2) of the RI Report or the site specific section (Setion 10) of the Addendum RI Report.

The cancer risks associated with future residential receptors exposed to groundwater exceeded 1E-04, the
upper end of the target risk range (Tables 3 and 4) based mainly on ingestion of TCE and 1,1-DCE in
groundwater and from inhalation of vapors while showering.

Estimates for noncancer risks associated with future industrial and future residential (groundwater) exposure
scenarios exceeded 1.0, the cutoff point below which adverse noncarcinogenic effects are not expected to
occur. VOCs (TCE and DCE) are the primary risk drivers.

Lead concentrations detected at the site during the RI were well below the EPA soil exposure guidelines for
children (400 ppm) and are not expected to be associated with a significant increase in blood-lead levels.

B. Ecological Risks

The ecological risk assessment estimates the risk posed to ecological receptors, such as aguatic and
terrestrial biota, from contamination at Site 26.

Site 26 is relatively small and consists of turfgrass or developed areas such as open storage or vehicle
parking areas that provide little ecological habitat. Wooded uplands are present northwest of the site. These
upland areas provide excellent habitat for a wide variety of terrestrial organisms. No wetlands, other
sensitive habitats, or threatened or endangered species of any kind exist in the vicinity of
-------
Site 26.

No significant contaminant migration pathways to the upland habitats exist at the site. Water in the process
leach tank/grease trap area is hot expected to migrate via overland runoff to the upland areas since water
tends to settle in this area, and the wooded areas are a few feet higher on grade than the area next to
Building GB-1. Groundwater discharge of contaminants to surface water is also insignificant since no wetlands
or other surface waters are present near the site.

VII. REMEDIAL ACTION OBJECTIVES (RAOs)

The overall objective for the remedy at OU-3 is to protect human health and the environment. The RAO to
protect human health is to prevent human exposure to contaminated groundwater. The RAO for protection of the
environment is to mitigate VOC contaminants in the groundwater.

VIII. DESCRIPTION OF REMEDIAL ACTION ALTERNATIVES

The purpose of the alternative development and screening process is to assemble an appropriate range of
possible remedial options to achieve the RAOs identified for OU-3. In this process, technically feasible
technologies are combined to form remedial alternatives that provide varying levels of risk reduction that
comply with federal (EPA) and state (NJDEP) guidelines for site remediation.

Engineering technologies capable of eliminating the unacceptable risks associated with exposure to
site-related soils, sediments, or groundwater were identified, and those alternatives determined to best meet
RAOs after screening were evaluated in detail. Table 5 presents the considered alternatives and the results
of preliminary screening.

A. Detailed Summary of Alternatives

Summaries of the remedial alternatives developed for OU-3 are presented in this section.

1. Alternative 1: No Action

The no-action alternative was developed as a baseline to which other alternatives may be compared, as
reguired by the NCP. No remedial actions would be taken to protect human health or the environment. The
purpose of this alternative is to evaluate the overall human health and environmental protection provided by
the site in its present state. No measures would be implemented to remove or contain the suspected
contaminant source (the process leach tank and associated soils), to prevent potential human exposure to site
groundwater, or to mitigate contaminant migration in the environment. Periodic reviews of site conditions,
typically every 5 years, and long-term monitoring of groundwater would be conducted under this alternative.

2. Alternative 2: Source Removal, Institutional Controls, and Long-Term Monitoring

Alternative 2 relies on source removal and institutional controls to limit exposures to hazardous substances.
No engineered treatment or containment would be employed to address contaminated groundwater; however, the
suspected contaminant source (the process leach tank and associated soils) would be removed to abet natural
attenuation of groundwater contamination. Institutional controls would be used to preclude use of untreated
groundwater. Long-term monitoring would be conducted to monitor natural attenuation effectiveness and
potential threats to human health and the environment. Site conditions and risks would be reviewed every 5
years.

Alternative 2 would provide protection of human health through suspected source removal and use of
institutonal controls to restrict consumption of contaminated groundwater until groundwater criteria are met.
Groundwater contaminants would decrease through natural attenuation over time. The effectiveness of this
protection would depend upon enforcement of institutional controls, because no actions would be taken to
accelerate cleanup of contaminated groundwater. Using the data available and a best-case groundwater modeling
approach, it is estimated that health risks would remain for a period of approximately 45 years, until
contaminant concentrations decrease to acceptable levels through natural attenuation. During this time
-------
period, the plume will initially expand downgradient with groundwater flow. If groundwater use restrictions
were not adequately enforced during the period of remediation, potential receptors could be exposed to site
risks.
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TABIiE 5
SITE 26 - SCREENING OF REMEDIAL ALTERNATIVES
FEASIBILITY STUDY
NWS EARLE, COLTS NECK, NEW JERSEY
ALTERNATIVE
1 No Action:
(Long-Term
Monitoring and Five-
Year Reviews)
2 Source Removal,
Institutional Controls,
Long-Term
Monitoring, and
Five-Year Reviews
3 Reactive Wall
Treatment (Source
Removal, In-Situ
Groundwater
Treatment,
Institutional Controls,
and Long-Term
Monitoring)
EFFECTIVENESS
Provides no additional protection of
human health or the environment. Does
not reduce potential for human
exposure to contaminants in
groundwater. Does not reduce
contaminant migration in the
environment. No reduction in toxicity,
mobility, or volume of contaminants.

Protects human health and the
environment through institutional
controls and natural attenuation.
Groundwater use would be restricted.
Would offer reduction of contaminant
leaching to groundwater through source
removal. Reduction in toxicity, mobility,
or volume of contaminants through
treatment of soils removed.
Groundwater contaminants would
naturally attentuate over time.

Protects human health and the
environment by removing the suspected
source of VOC contamination leaching
to groundwater. Would prevent
continuing migration of TCE plume until
treatment and natural attenuation
remediate the contaminants.
Groundwater use would be restricted.
Toxicity and volume of contaminants
would be reduced through treatment
only through source treatment.
IMPLEMENTABILITY
Readily implementable. No technical or
administrative difficulties.
COST
Capital:
none
O&M: low
COMMENTS
Retained as baseline
alternative in accordance
with NCP.
Readily implementable. No technical or
administrative difficulties.
Capital:
low
O&M: low
Relative to Alt. 1, provides
greater protectiveness in
the long term. Would result
in reduction of groundwater
contaminant levels.
Retained.
Implementable. Reactive wall technology
is innovative and is not well developed but
offers potential for in-situ treatment with
no ex-situ treatment residuals. No
technical or administrative difficulties.
Personnel and materials necessary to
implement alternative are limited;
currently, only one commercial firm is
available to implement full-scale
construction.
Capital:
moderate
high
O&M:
moderate
This technology will likely
degrade TCE in the
subsurface. May offer
comparable degree of
protectiveness as Alt, 4.

Retained
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TABIiE 5
SITE 26 - SCREENING OF REMEDIAL ALTERNATIVES
FEASIBILITY STUDY
NWS EARLE, COLTS NECK, NEW JERSEY
PAGE 2 OF 3
ALTERNATIVE
4 Pump-And-Treat:
(Source Removal,
Groundwater
Extraction and
Treatment,
Institutional Controls,
and Long-Term
Monitoring)
5 Air Sparging Soil
Vapor Extraction:
(Source Removal,
Institutional Controls,
and Long-Term
Monitoring)
EFFECTIVENESS
Protects human health and the
environment by removing suspected
source of VOC contamination leaching
to groundwater. Would actively reduce
TCE concentrations in the plume and
prevent continuing migration of the TCE
plume until extraction/treatment and
natural attenuation remediate the
contaminants. Groundwater use would
be restricted. Toxicity and volume of
contaminants would be reduced
through treatment.

Protects human health and the
environment by removing suspected
source of VOC contamination leaching
to groundwater. Would actively reduce
TCE concentrations in the plume and
prevent continuing migration of the TCE
plume until extraction/treatment and
natural attenuation remediate the
contaminants. Groundwater use would
be restricted. Toxicity and volume
would be reduced through treatment
IMPLEMENTABILITY
Readily imptementable. Specialized
treatment eguipment is reguired but is
available from several vendors. No
technical or administrative difficulties.
Personnel and materials necessary to
implement alternative are widely available.
COST
Capital:
moderate
O&M:
moderate
COMMENTS
Would employ well
demonstrated treatment
process options. Retained
as representative treatment
alternative.
Implementable technology is well proven
and offers potential for active in-situ
treatment, depending on actual site
conditions. Pre-design and pilot studies
would be reguired, but pilot system could
easily be expanded to full-scale system in
the field. System reguires significant
sampling and analysis to gauge impact
across the wide volume of soil in the
remediation zone.
Capital:
moderate
O&M
moderate
to high
This technology set offers
the advantage of actively
treating the large volume of
contaminated media and
could reguire less time than
the passive treatment or
capture and treatment of the
plume at the leading plume
edge. This technology
reguires substantial
chemical and biological
monitoring to control the
process. Retain for further
evaluation.
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TABIiE 5
SITE 26 - SCREENING OF REMEDIAL ALTERNATIVES
FEASIBILITY STUDY
NWS EARLE, COLTS NECK, NEW JERSEY
PAGE 3 OF 3
ALTERNATIVE
EFFECTIVENESS
IMPLEMENTABILITY
COST
COMMENTS
Engineered
Bioremediation:
(Source Removal,
In-Situ Engineered
Bioremediation,
Institutional Controls,
and Long-Term
Monitoring)
Protects human health and the
environment by removing the suspected
source of VOC contamination leaching
to groundwater. Would actively
remediate the entire plume by
engineered bioremediation.
Groundwater use would be restricted
until clean-up levels are achieved.
Toxicity and volume of contamination
would be reduced through treatment
Implementable, although technology is Capital:
patented. Technology is innovative and moderate
has rarely been applied on a full scale but O&M:
offers potential for in-situ treatment with no moderate
ex-situ treatment residuals. Personnel
and materials necessary to implement are
available; however, it is not clear how
licensable the technology is.
This technology has the
potential to degrade
chlorinated VOCs in the
subsurface, in a shorter
time frame of all alternatives
but Alternative 5. However,
technology development is
limited, and is licensability
is uncertain. Because there
are two other retained
innovative technologies and
two active treatment
technologies and the
ultimate success of
engineered bioremediation
is uncertain, this technology
is eliminated.
-------
Periodic long-term monitoring would be conducted to assess contaminant status and potential threats to human
health and the environment and to gauge the progress of anticipated natural attenuation. Site conditions and
risks would be formally reviewed every 5 years to evaluate remedy progress.

Because site groundwater does not meet New Jersey groundwater guality standards, a classification exception
area (CEA) pursuant to N.J.A.C. 7:9-6 would be established to provide the state official notice that the
constituent standards will not be met for a specified duration and to ensure that use of groundwater in the
affected area is suspended until standards are achieved.

If the excavated process leach tank and/or soils were determined to be hazardous wastes, their handling,
management, and off-site transport would be conducted in accordance with RCRA hazardous waste generator and
transporter reguirements [40 CFR Parts 262 and 263] and New Jersey labeling, records, and transportation
reguirements [N.J.A.C. 7:26-7].

Under Alternative 2, if it is determined that soils are subject to RCRA Land Disposal Restrictions (LDRs) [40
CFR 268], the source materials would be treated off site prior to disposal, in accordance with these
regulations. Any wastes determined to be subject to LDRs would be disposed off site at a RCRA Subtitle C
facility.

3. Alternative 3: Reactive Wall Treatment (Source Removal, In-Situ Permeable Reactive
Wall, Groundwater Treatment, Institutional Controls, and Long-Term Monitoring)

Alternative 3 employs suspected source removal, in-situ groundwater treatment, and institutional controls to
protect human health and the environment. The suspected contaminant source (the process leach tank and
associated VOC-contaminated soils) would be removed for disposal off station. Groundwater would be treated in
situ using permeable reactive wall technology. Because of the relatively slow groundwater velocity, it is
anticipated that a significant portion of the groundwater contaminants would naturally attenuate before they
pass through the reactive wall. Institutional controls would be implemented to prevent exposure to
contaminated groundwater for the duration of the groundwater treatment period, until GWQS are achieved.
Long-term monitoring would be conducted for the duration of the remediation period to assess the
effectiveness of the remedial action and to determine when the remediation is complete. Site conditions and
risks would be reviewed every 5 years until the groundwater remediation is complete.

A principal component of Alternative 3 is in-situ permeable reactive wall groundwater treatment. This
innovative technology utilizes granular iron to break down the chlorinated solvents as the groundwater plume
passes through the wall. Since the plume would be treated in situ, no pumping would be reguired and the
natural groundwater contours would not be disturbed. The potential for system failure would be minimized
because no mechanical or electrical eguipment would be used. An array of monitoring wells across the
treatment zone would be used to evaluate the effectiveness of the treatment wall and to determine when
maintenance is reguired.

Although this technology is innovative and its long-term track record is limited, several pilot studies have
been conducted with impressive results. Full-scale implementation of the technology is underway at several
locations. The feasibility study (FS) concluded that subsurface conditions at Site 26 are favorable for a
reactive wall. The permeable treatment wall would act as a passive treatment barrier, which would effectively
prevent off-site migration of contaminated groundwater. Therefore, upon completion of the treatment wall,
downgradient receptors would be protected.

The treatment wall would not immediately protect potential receptors of contaminated groundwater beneath Site
26; long-term, permanent protecton would be achieved after a treatment duration of approximately 45 years,
based on available data and groundwater modeling assuming passive treatment. In the interim, contaminants
would be removed both by the treatment wall and natural attenuation.

In the interim period, until remediation goals for site groundwater have been achieved, human health would be
protected through use of institutional controls that would restrict use of untreated contaminated groundwater
as drinking water. The effectiveness of this interim protection would depend upon adeguate enforcement. If
groundwater use restrictions were not adeguately enforced, existing health risks would remain until
-------
groundwater contaminant concentrations decreased to acceptable levels.

If the excavated process leach tank and/or soils were determined to be hazardous wastes, their handling,
management, and off-sifte transport would be conducted in accordance with RCRA hazardous waste generator and
transporter reguirements [40 CFR Parts 262 and 263] and New Jersey labeling, records, and transportation
reguirements [N.J.A.C. 7:26-7).

Under Alternative 3, if it is determined that soils are subject to RCRA Land Disposal Restrictions [40
CFR 268], soils would be treated off site prior to disposal, in accordance with these regulations. Any
wastes determined to be subject to LDRs would be disposed off site at a RCRA Subtitle C facility.

4. Alternative 4: Pump-And-Treat (Source Removal, Groundwater Extraction
Groundwater Treatment by Air Stripping, Institutional Controls, and Long-Term Monitoring)

Alternative 4 employs suspected source removal, groundwater pumping and treatment, and institutional controls
to protect human health and the environment. The suspected contaminant source (the process leach tank and
associated VOC contaminated soils) would be removed for disposal off-station. A groundwater containment
system consisting of groundwater extraction wells would be placed near the downgradient edge of the plume,
and the groundwater would be extracted and treated above ground by air stripping. Additional groundwater
extraction wells would be placed in the vicinity of the high-concentration plume area, also for groundwater
pumping and above-ground treatment. Treated (clean) groundwater would be re-introduced to the aguifer via
infiltration galleries downgradient of the extraction point. Preliminary estimates of the
amount of solvents to be stripped indicate that air emissions treatment will not be reguired. Institutional
controls would be implemented to prevent exposure to contaminated groundwater for the duration of the
groundwater treatment period, until GWQS are achieved. Periodic long-term monitoring would be conducted for
the duration of the remediation period to assess the effectiveness of the remedial action and to determine
when the remediation is complete. Site conditions and risks would be formally reviewed every 5 years until
the groundwater remediation is complete.

Alternative 4 would employ source removal and groundwater extraction and treatment to provide long-term
protection of human health and the environment. The groundwater extraction system would be designed to
prevent off-site migration of contaminated groundwater and to actively treat the VOC plume. Upon completion
of the extraction system, downgradient receptors of contaminated groundwater would be protected. Potential
users of contaminated groundwater beneath Site 26 would not ts protected by Alternative 4 until groundwater
remediation goals were achieved throughout the plume. It is anticipated that long-term, permanent protection
would be achieved after a treatment duration of less than 45 years. During this period, groundwater
contaminants would be removed both by the extraction system and through natural attenuation. Additional
treatment efficiency could be attained by increasing the number of pumping wells, but this benefit would be
offset by increased capital and operating costs.

In the interim period, until remediation goals for site groundwater have been achieved human health would be
protected through use of institutional controls that would restrict use of untreated contaminated groundwater
as drinking water. The effectiveness of this interim protection would depend entirely upon adeguate
enforcement. If groundwater use restrictions were not adeguately enforced, existing health risks would remain
until groundwater contaminant concentrations decreased to acceptable levels.

If the excavated process leach tank and/or soils were determined to be hazardous wastes, their handling;
management, and off-site transport would be conducted in accordance with RCRA hazardous waste generator and
transporter reguirements [40 CFR Parts 262 and 263] and New Jersey labeling, records, and transportation
reguirements [N.J.A.C. 7:26-7].

Under Alternative 4, if it is determined that the source materials are subject to RCRA Land Disposal
Restrictions [40 CFR 268], the source materials would be treated off site prior to disposal, in accordance
with these regulations. Any wastes determined to be subject to LDRs would be disposed off site at a RCRA
Subtitle C facility.

5. Alternative 5. Air Sparging with Soil Vapor Extraction (Source Removal, Institutional
-------
Controls, and Long-Term Monitoring)

Under Alternative 5, the suspected source of groundwater contaminants (the process leach tank and associated
VOC-contaminated soils) would be removed, and the VOCs present in groundwater and saturated soils would be
removed from the aguifer through a combination of air sparging and soil vapor extraction (AS/SVE), which
comprises an active in-situ remediation process. Depending on the actual concentrations of VOCs in the gas
stream, vapor phase activated carbon may be reguired to treat captured vapors above ground to meet applicable
air emission standards. Preliminary estimates of the amount of solvents to be stripped indicate that air
emissions treatment will not be reguired. Spent activated carbon would be sent off site for reuse, recycling,
or destruction. Institutional controls would be implemented to prevent exposure to contaminated groundwater
for the duration of the groundwater treatment period, until GWQC are achieved. Periodic long-term monitoring
would be conducted for the duration of the remediation period to assess the effectiveness of the remedial
action and to determine when the remediation is complete. Site conditions and risks would be formally
reviewed every 5 years until the groundwater remediation is complete.

Using the AS/SVE system for mass transfer, it is anticipated that the greater part of the chlorinated VOCs
would be removed from groundwater and soils. However, the continuous introduction of air into the subsurface
maintains a high dissolved oxygen level in both the saturated and unsaturated zones. High dissolved oxygen
conditions are not generally favorable to anaerobic biological activity of the chlorinated VOCs in situ.
Biodegradation of VOCs by the indigenous microbe population generally reguires anaerobic conditions.
Therefore, it is proposed that any AS/SVE remediation scheme would consist of a preliminary active AS/SVE
period to treat the areas of significant TCE concentration and remove the bulk of the mass of chlorinated
hydrocarbons, followed by a period of long-term monitoring and natural attenuation of the chlorinated
hydrocarbons in an anaerobic state.

Alternative 5 would employ suspected source removal and in-situ groundwater treatment to provide long-term
protection of human health and the environment. The groundwater treatment system would be designed to reduce
volume and concentration of contaminated groundwater; therefore, upon successful start-up of the treatment
system (the plume area could actually widen during initial operations), downgradient receptors of
contaminated groundwater would begin to be protected. However, potential users of contaminated groundwater
beneath Site 26 would not be protected by Alternative 5 until groundwater remediation goals were achieved
throughout the plume. It is anticipated that long-term, permanent protection would be achieved after a
treatment duration of approximately 5 years. During this period, groundwater contaminants would be removed
both by the AS/SVE, which comprises an active in-situ remediation process extraction system, and by natural
attenuation.

In the interim, until remediation goals for site groundwater have been achieved, human health would be
protected through the use of institutional controls that would restrict the use of untreated contaminated
groundwater as drinking water. The effectiveness of this interim protection would depend entirely upon
adeguate enforcement. If groundwater use restrictions were not adeguately enforced, existing health risks
would remain until groundwater contaminant concentrations decreased to acceptable levels.

If the excavated process leach tank and/or soils were determined to be hazardous wastes, their handling,
management, and off-site transport would be conducted in accordance with RCRA hazardous waste generator and
transporter reguirements [40 CFR Parts 262 and 263) and New Jersey labeling, records, and transportation
reguirements [N.J.A.C. 7:26-7].

Under Alternative 5, if it is determined that the source materials are subject to RCRA Land Disposal
Restrictions [40 CFR 268], the source materials would be treated off site prior to disposal, in accordance
with these regulations. Any wastes determined to be subject to LDRs would be disposed off site at a RCRA
Subtitle C facility.

6. Alternative 6: Engineered Bioremediation (Source Removal, Engineered
Bioremediation, Institutional Controls, and Long-Term Monitoring)

Under Alternative 6, the suspected source of groundwater contaminants (the process leach tank and associated
VOC-contaminated soils) would be removed and the VOCs present in groundwater and saturated soils would be
-------
actively bioremediated in situ through engineered enhancement of natural processes. Institutional controls
would be implemented to prevent exposure to contaminated groundwater for the duration of the groundwater
treatment period, until GWQC are achieved. Long-term monitoring would be conducted for the duration of the
remediation period to assess the effectiveness of the remedial action and to determine when the remediation
is complete. Site conditions and risks would be reviewed every 5 years until the groundwater remediation is
complete.

Alternative 6 would employ suspected source removal and in-situ groundwater treatment to provide long-term
protection of human health and the environment. The groundwater treatment system would utilize bioremediation
to reduce volume and concentration of contaminated groundwater; therefore, upon successful start-up of the
bioremediation system, downgradient receptors of contaminated groundwater would begin to be protected.
However, potential users of contaminated groundwater beneath Site 26 would not be protected by Alternative 6
until groundwater remediation goals were achieved throughout the plume. It is anticipated that long-term,
permanent protection would be achieved after a treatment duration of approximately 5 years. During this
period, groundwater contaminants would be removed both by enhanced bioremediation and natural attenuation.

Under Alternative 6, if it is determined that the source materials are subject to RCRA Land Disposal
Restrictions [40 CFR 268], the source materials would be treated off site prior to disposal, in accordance
with these regulations. Any wastes determined to be subject to LDRs would be disposed off site at a RCRA
Subtitle C facility.

IX. SUMMARY AND COMPARATIVE ANALYSIS OF ALTERNATIVES

The remedial action alternatives described in Section VIII were evaluated using the following criteria,
established by the NCP:

Threshold Criteria: Statutory reguirements that each alternative must satisfy in order to be eligible for
selection.

1. Overall protection of human health and the environment - draws on the assessments
conducted under other evaluation criteria and considers how the alternative addresses
site risks through treatment, engineering, or institutional controls.

2. Compliance with ARARs - evaluates the ability of an alternative to meet Applicable or
Relevant and Appropriate Reguirements (ARARs) established through federal and state
statutes and/or provides the basis for invoking a waiver.

Primary Balancing Criteria: Technical criteria upon which the detailed analysis is primarily based.

3. Long-term effectiveness and permanence - evaluates the ability of an alternative to
provide long-term protection of human health and the environment and the magnitude of
residual risk posed by untreated wastes or treatment residuals.

4. Reduction of mobility, toxicity, or volume through treatment - evaluates an alternative's
ability to reduce risks through treatment technology.
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5. Short-term effectiveness - addresses the clean-up timeframe and any adverse impacts
posed by the alternative during the construction and implementation phase, until clean-up
goals achieved.

6. Implementability - is an evaluation of technical feasibility, administrative feasibility, and
availability of services, and material reguired to implement the alternative.

7. Cost - includes an evaluation of capital costs and annual operation and maintenance (OW) costs.

Modifying Criteria: Criteria considered throughout the development of the preferred remedial alternative and
formally assessed after the public comment period, which may modify the preferred alternative.

8. Agency acceptance indicates the EPA's and the state's response to the alternatives in
terms of technical and administrative issues and concerns.

9. Community acceptance evaluates the issues and concerns the public may have regarding
the alternatives.

The remedial alternatives were compared to one another based on the nine selection criteria, to identify
differences among the alternatives and discuss how site contaminant threats are addressed.

Based on the initial screening of remedial alternatives, Alternatives 1,2,3,4, and 5 were retained for
further consideration. A detailed review of Alternatives 1 through 5 is included in this section and
summarized in Table 6. Alternative 6: Engineered Bioremediation was eliminated because of uncertainty
regarding the current state of development of the technology and licensability guestions.

A. Overall Protection of Human Health and the Environment

Because no actions would be conducted, Alternative 1 would not reduce contaminant migration from the source
area to groundwater and groundwater contamination may increase with time. Although Alternative 2 would remove
the source, groundwater contamination would continue to migrate unabated. Because no actions would be taken
under Alternatives 1 and 2 to contain or remediate groundwater, potential health risks would remain for an
extended period of time.
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TABLE 6
SITE 26 - COMPARATIVE ANALYSIS OF REMEDIAL ACTION ALTERNATIVES
FEASIBILITY STUDY
NWS EARLE, COLTS NECK, NEW JERSEY
ALTERNATIVE 1:
NO ACTION
ALTERNATIVE 2:
NATURAL
ATTENUATION
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
ALTERNATIVE 3:
REACTIVE WALL
ALTERNATIVE 4:
PUMP-AND-TREAT
ALTERNATIVE 5:
AIR SPARGING SOIL
EXTRACTION
Provides no additional
protection against
human exposure to
contaminated
groundwater.
Carcinogenic and
NO institutional
controls implemented
to restrict use of
untreated
contaminated
groundwater for
Institutional
controls would
minimize potential
exposure to site
groundwater by
prohibiting its use
Excavation and
off-site disposal of
the process leach
tank and
associated
contaminated
soils would
reduce leaching of
contaminants to

groundwater,
facilitating natural
attenuation of
contaminants. In
time, contaminant
concentrations
would reach
levels that would
not pose excess
risk.
The proposed in-situ system would
immediately prevent exposure to
downgradient receptors by treating the
advancing plume while natural
attenuation would ultimately reduce
groundwater contaminant concentrations
Institutional controls would minimize
potential exposure to site groundwater
during the treatment period by prohibiting
its use as drinking water.
Provides collection and
ex-situ treatment of the
advancing contaminant
plume, which would
immediately prevent
exposure to downgradient

receptors while natural
attenuation ultimately
reduces groundwater
contaminant
concentrations to levels
that would not pose
excess risk.
groundwater during the
treatment period by
prohibiting its use as
drinking water.

Excavation and off-site
disposal of the process
leach tank and associated
contaminated soils would
reduce leaching of
contaminants to
groundwater, facilitating
groudwater remediation.
Air sparging and soil vapor
extraction treatment processes,
combined with enhanced
biodegradation and natural
attenuation would initially result in
wider plume volume/area but would
actively reduce the concentration of
contaminants in the entire plume.
This treatment alternative would be
expected to reduce overall
contaminant concentration of the
entire plume more guickly than
other alternatives.

Institutional controls would minimize
potential exposure to site
groundwater during the treatment
period by prohibiting its use as
drinking water.

Excavation and off-site disposal of
the process leach tank and
associated contaminated soils would
reduce leaching of contaminants to
groundwater, facilitating groundwater
remediation.
Mitigate
Migration of
VOC
Contaminated
Groundwater
No actions taken to
reduce migration of
contaminated
groundwater. Relies
on natural
attenuation.
The permeable reactive wall treatment
system, installed immediately
downgradient of the contaminant plume,
would prevent further migration of
contaminated groundwater by degrading
dissolved contaminants as they migrate
through the wall.
The groundwater
extraction and treatment
system would contain and
treat the contaminant
plume, preventing further
migration of contaminated
groundwater.
The groundwater plume would
initially widen, but the overall
treatment period would be shorter
than other alternatives.
-------
TABLE 6
SITE 26 - COMPARATIVE ANALYSIS OF REMEDIAL ACTION ALTERNATIVES
FEASIBILITY STUDY - NWS EARLE, COLTS NECK, NEW JERSEY
PAGE 2 OF 7
CRITERION:
COMPLIANCE WITH ARARs
ALTERNATIVE 2:
NATURAL ATTENUATION
ALTERNATIVE 5:
AIR SPARGING SOIL
VAPOR EXTRACTION
Groundwater contaminant
concentrations would initially
exceed state GWQC; over time
GWQC would be achieved by
natural attenuation.

A classification exception area
(CEA) would be established to
provide the state official
notification that standards would
not be met for a specified duration.
Groundwater contaminant
concentrations would initially exceed
GWQC; over time, treatment and
natural attenuation would reduce
contaminant levels below GWQC.

A classification exception area (CEA)
would be established to provide the
state official notification that standards
would not be met for a specified
duration.
Location-Specific Not Applicable.
ARARs

Not Applicable.
If soils and sediments are
determined to be hazardous,
Alternative 2 would comply with
federal and state ARARs for
generation, transport and disposal
of hazardous wastes.
Not Applicable.
Not Applicable.
If soils and sediments are
determined to be
hazardous, Alternative 4
would comply with federal
and state ARARs for
transport of hazardous
waste.
The on-site treatment facility
would be constructed and
operated in accordance with
federal and state hazardous
waste facility regulations.
-------
TABLE 6
SITE 26 - COMPARATIVE ANALYSIS OF REMEDIAL ACTION ALTERNATIVES
FEASIBILITY STUDY - NWS EARLE, COLTS NECK, NEW JERSEY
PAGE 3 OF 7
CRITERION:

LONG-TERM EFFECTIVENESS AND PERMANENCE

Existing risks would remain.
Future residential receptor of site
groundwater: 1.7 x 10 -4 cardnogenic
and HI > 1 non-cardnogenic risks for
three target organs.

Future industrial receptor of site
groundwater: HI > 1 non-
carcinogenic risks for three target
organs.
ALTERNATIVE 2:
NATURAL ATTENUATION
Implementation and enforcement of
institutional controls would reduce
risks from exposure to site
groundwater to less than 1 x 10 -6
and HI less than 1.0. Over time,
natural attenuation would result in
permanently reduced risks.
ALTERNATIVE 5:
AIR SPARGING SOIL
VAPOR EXTRACTION
Groundwater treatment would result
in permanent reduction of risks from
exposure to site groundwater to less
than 1 x 10 -6 and HI less than 1.0.

In the interim, until groundwater
remediation goals are achieved,
implementation and enforcement of
institutional controls would reduce
risks from exposure to site
groundwater to less than 1 x 10 -6 and
HI less than 1.0.
No new controls implemented.
Long-term enforcement of
institutional controls would be
reguired to ensure their
effectiveness for preventing use of
contaminated groundwater.
ve wall treatment is
tive process that
rated primarily in
-scale projects over
. Although the
promise, its long-
ss is uncertain.
tions include
ing of the reactive
duced permeability
'f precipitated
The technology vendor recommends
agitation of the reactive wall
materials every 5 to 10 years to
liberate deposited inorganic
precipitates. If the wall became
ineffective and could not be repaired,
the reactive metal materials or the
entire wall would have to be
replaced.

Regular process monitoring would
effectively identify any changes in
the effectiveness of the process.

Long-term enforcement of
institutional controls would be
reguired to ensure their effectiveness
for preventing use of contaminated
groundwater.
Groundwater extraction
and air stripping are widely
used, effective
technologies for the
remediation of VOC
contaminated groundwater.
There is little uncertainty
associated with long-term
operation or maintenance
of the system.

The process would be
easily monitored and
maintained. Routine
maintenance and
replacement of system
components could be
accomplished with little
interruption of system
operation.

Long-term enforcement of
installation controls would
be reguired to ensure their
effectiveness for
preventing use of
contaminated groundwater.
Air sparging and soil vapor
extraction are widely used,
effective technologies for
the remediation of VOC
contaminated groundwater.
There is little uncertainty
associated with long-term
operation or maintenance of
the system.

The process would be
easily monitored and
maintained. Routine
maintenance and
replacement of system
components could be
accomplished with little
interruption of system
operation.

Regular process monitoring
would effectively identify
any changes in the
effectiveness of the
process.

Long-term enforcement of
institutional controls would
be reguired to ensure their
effectiveness for preventing
use of contaminated
groundwater.
-------
TABLE 6
SITE 26 - COMPARATIVE ANALYSIS OF REMEDIAL ACTION ALTERNATIVES
FEASIBILITY STUDY - NWS EARLE, COLTS NECK, NEW JERSEY
PAGE 4 OF 7
CRITERION:
ALTERNATIVE 2:
NATURAL ATTENUATION
ALTERNATIVE 5:
AIR SPARGING SOIL
VAPOR EXTRACTION
Review would be required
since groundwater
contaminants would be left
place.
REDUCTION OF TOXICITY, MOBILITY, OR VOLUME THROUGH TREATMENT
Review would be required
since groundwater
contaminants would be left in
place and institutional controls
would be implemented.
Review would be required for the
duration of the groundwater
remediation period since
groundwater contaminants would
remain above remediation goals
and institutional controls would be
implemented.
In-situ permeable reactive wall.
Air stripping with activated
carbon polishing.
No reduction, since
treatment would be
employed.
2 million gallons contaminated
groundwater, containing 17,000
grams TCE plus other VOCs,
remediated per year.

The In-situ treatment system would
contain the contaminant plume and
degrade the chlorinated VOCs to
reduce the toxicity, mobility, and
volume of contaminated
groundwater. Over a period of
approximately 45 years, the
contaminants of concern in site
groundwater would be reduced to
acceptable levels.
Entire plume
The gr
extrac
system
contam
remove
reduce
mobili
contam
Over a
approx
the co
concer
ground'
reduce'
oundwa
tion a
would
inant
the V
the t
ty, an'
inated
perio'
imatel
ntamin
n in s
later
d to
ter
nd treatment
contain the
plume and
OCs to
oxicity,
.d volume of
groundwater.
»d of
years,
ants of
ite
would be
cceptable
levels.
is reduced by
stripping VOCs
plume volume.
is not affected,
as remediation
es, the plume
expected to
The volume of
e (contaminated
above GWQC)
ted to grow
nitial treatment,
iminish with time.
-------
TABLE 6
SITE 26 - COMPARATIVE ANALYSIS OF REMEDIAL ACTION ALTERNATIVES
FEASIBILITY STUDY - NWS EARLE, COLTS NECK, NEW JERSEY
PAGE 5 OF 7
ALTERNATIVE 1:
NO ACTION

Not Applicable
ALTERNATIVE 2:
NATURAL ATTENUATION
Not Applicable
ALTERNATIVE 3:
REACTIVE WALL
ALTERNATIVE 4:
PUMP-AND-TREAT
ALTERNATIVE 5:
AIR SPARGING SOIL
VAPOR EXTRACTION
Yes, contaminants are
removed and/or treated to
form non-toxic compounds.
Statutory
Preference for
Treatment

SHORT-TERM EFFECTIVENESS
Community
Protection
Environmental
Impacts
No risk to community
anticipated.
No risk to workers
anticipated if proper PPE is
used during long-term
monitoring.
No significant risk to community
anticipated. Engineering controls
would be used during
implementation to mitigate risks.

No significant risk to workers
anticipated it proper PPE is used
during source removal and
decontamination and long-term
monitoring.
No adverse impacts to the
environment anticipated.
Engineering controls would be
used during implementation to
mitigate risks.
No significant risk to workers
anticipated if proper PPE is
used during source removal and
decontamination, installation of
the permeable reaction wall,
and tong-term monitoring.
No significant risk to workers
anticipated if proper PPE is used
during source removal and
decontamination, installation and
operation of the groundwater
extraction and treatment systems,
and long-term monitoring.
No significant risk to
workers anticipated if
proper PPE is used during
source removal and
decontamination,
installation and operation
of the groundwater air
sparging and soil vapor
extraction systems, and
long-term monitoring.
-------
Time Until Action
is Complete
Not applicable .
50 years until contaminants are
reduced to acceptable
concentrations by natural
attenuation.
10 months until RAO for
mitigating migration of VOC
contaminated groundwater is
achieved.

45 years until contaminants are
reduced to acceptable
concentrations by in-situ
groundwater treatment.
45 years until contaminants are
reduced to acceptable
concentrations by extraction and
treatment of groundwater.
1 year until RAO for
preventing exposure to site
groundwater is achieved
through implementation of
institutional controls.
Approximately 5 years until
RAO for mitigating
migration of VOC
contaminated groundwater
is achieved.

Approximately 5 years until
contaminants are reduced
to acceptable
concentrations by air
sparging/soil vapor
extraction and biodegration
in groundwater.
-------
TABLE 5
SITE 26 - COMPARATIVE ANALYSIS OF REMEDIAL ALTERNATIVES
FEASIBILITY STUDY - NWS EARLE, COLTS NECK, NEW JERSEY
PAGE 6 OF 7
CRITERION:
IMPLEMENTABILITY
ALTERNATIVE 1:
NO ACTION
ALTERNATIVE 2:
NATURAL ATTENUATION
ALTERNATIVE 3:
REACTIVE WALL
ALTERNATIVE 4:
PUMP-AND-TREAT
ALTERNATIVE 5:
AIR SPARGING SOIL
VAPOR EXTRACTION
Common construction techniques
used for excavation and off-site
disposal of the concrete block leach
tank and associated contaminated
soils.
Common construction equipment
and somewhat specialized
construction techniques used for
installation of treatment wall. With
vendor traininq and oversiqht, wall
could be installed by non-spedallzed
construction crews.

Common construction techniques
used for excavation and off-site
disposal of the concrete block leach
tank and associated contaminated
soils.
Common well installation and
construction techniques and
equipment used for installation
of extraction system. Modular
treatment system would be
easily constructed.
Common construction
techniques used for excavation
and off-site disposal of the
concrete block leach tank and
associated contaminated soils.
Common well installation
and construction techniques
and equipment used for
installation of treatment
system. Modular treatment
system would be easily
constructed.

Common construction
techniques used for
excavation and off—site
disposal of the concrete
block leach tank and
associated contaminated
soils.
Additional actions would
be easily implemented if
required.

Groundwater monitorinq
would provide assessment
of contaminant presence,
miqration, and chanqes in
site conditions.
Same as Alternative 1.
Same as Alternative 1.
Same as Alternative 1.
Same as Alternative 1.
Same as Alternative 2.
Permits would be required and
obtainable for off-base transportation
and disposal of contaminated source
area soils. Permits would not be
required for on-base disposal.
-------
TABLE 6
SITE 26 - COMPARATIVE ANALYSIS OF REMEDIAL ALTERNATIVES
FEASIBILITY STUDY - NWS EARLE, COLTS NECK, NEW JERSEY
PAGE 7 OF 7
CRITERION:
ALTERNATIVE 1:
NO ACTION
ALTERNATIVE 2:
NATURAL ATTENUATION
ALTERNATIVE 3:
REACTIVE WALL
ALTERNATIVE 4:
PUMP-AND-TREAT
Ability of
Treatment,
Storage
Capacities, and
Disposal Services
None required.
Alt. 2A: Sufficient corn.rn.er cial
landfill capacity available for
materials requiring disposal.
Alt. 2B: Sufficient area available
for disposal of materials at both
on-base landfills.
Alt. 3A: Sufficient commercial landfill
capacity available for materials
requiring disposal.
Alt. 3B: Sufficient area available for
disposal of materials at both on-base
landfills.
Alt. 4A: Sufficient commercial
landfill capacity available for
materials requiring disposal.
Alt. 4B: Sufficient area available for
disposal of materials at both on-
base landfills.
Alt. 5A: Sufficient
commercial landfill capacity
available for materials
requiring disposal.
Alt. 5B: Sufficient area
available for disposal of
materials at both on-base
landfills.
Availability of
Equipment
Specialists, and
Materials
Personnel and equipment
available for
implementation of long-
term monitoring and 5 —
year reviews.
Ample availability of companies
with trained personnel,
equipment, and materials to
perform source removal, long-
term monitoring, and 5-year
reviews.
Ample availability of companies with
trained personnel, equipment, and
materials to perform source removal,
treatment system installation and
operation, long-term monitoring, and
5-year reviews.
Ample availability of companies
with trained personnel, equipment,
and materials to perform source
removal, extraction and treatment
system installation and operation,
long-term monitoring, and 5-year
reviews.
Ample availability of
companies with trained
personnel, equipment, and
materials to perform source
removal, AS/SVE treatment
system installation and
operation, long-term
monitoring, and 5-year
reviews.
Availability of
Technology
Not required.
Reactive wall technology only
available from one vendor, but the
equipment, materials, and personnel
required to construct treatment system
are available from several
vendors/companies.
Groundwater extraction and air
stripping are widely used,
conventional technologies available
from a variety of companies.
AS/SVE is a widely used
readily available
combination of
equipment/techniques
provided by a variety of
companies.
Present-Worth
Cost*
-------
Alternatives 3, 4, and 5 would provide protection of both human health and the environment through treatment
of contaminated groundwater and implementation of institutional controls. Removal of the suspected source of
groundwater contamination should facilitate the remediation of contaminated groundwater. The effectiveness of
this alternative for interim protection of human health (until groundwater remediation is complete) is
dependent on enforcement of institutional controls.

B. Compliance with ARARs

Implementation of Alternatives 2, 3, 4, and 5 would comply with all ARARs and TBCs identified in the FS, with
the exception of the New Jersey GWQS [N.J.A.C. 7:9-6]. None of the alternatives would initially comply with
these state ARARs for attainment of groundwater guality criteria; however, Alternatives 2, 3, 4, and 5 would
include a provision to seek a temporary exemption (CEA) from these reguirements until the GWQS are achieved
through natural attenuation (Alternative 2 only) or treatment. Alternative 1 would not comply with these
standards or include a provision to seek temporary exemption. Five-year reviews would be necessary until
ARARs are met.

C. Long-Term Effectiveness and Permanence

Only Alternatives 3, 4, and 5 offer long-term protection of both human health and the environment. All three
alternatives would result in permanent reduction of risks from exposure to site groundwater in a reasonable
timeframe. Alternative 2 includes source removal and provides protection of human health through use of
institutional controls. Alternative 1 does not provide any additional protection of human health or the
environment.

Alternatives 3, 4, and 5 all employ groundwater treatment, institutional controls, and removal of the
suspected source of groundwater contaminants to protect human health and the environment. All three would
result in permanent reduction in risks from exposure to site groundwater to less than EPA guideline limits.

Alternatives 3 and 4 initially would provide identical protectiveness: downgradient receptors and the
environment would be protected upon installation and start-up of the treatment systems. In the initial stages
of implementation of Alternative 5, the solvent plume would continue to spread with the flow of groundwater,
with minimal, if any, impact on receptors. After operational start-up, Alternative 5 has the potential to
remove a greater volume of the contamination in a shorter period than Alternatives 3 and 4. Protection of
downgradient receptors would be expected to be achieved in a shorter period for Alternatives 4 and 5, as
compared with Alternative 3.

Under all these alternatives, the effectiveness of the interim protection would depend upon enforcement of
institutional controls; if groundwater use restrictions were not enforced, protection of human health would
not be achieved until the groundwater remediation is complete.

Alternative 3 employs an innovative in-situ technology to treat contaminated groundwater. The technology
shows great promise for treating contaminated groundwater, but it has not been demonstrated in long-term
full-scale projects. The reliability of Alternatives 4 and 5 is expected to be high; both employ treatment
systems that have been widely demonstrated for remediation of VOC-contaminated groundwater.

Long-term monitoring and 5-year reviews would be reguired for all five alternatives until groundwater
contaminant concentrations decrease to acceptable levels through treatment or natural attenuation. Regular
monitoring would allow the responsible agency to assess remediation progress or changes in contaminant status
and identify potential impacts to downgradient receptors.

D. Reduction of Toxicity, Mobility, or Volume Through Treatment

Alternative 1 would not reduce the toxicity, mobility, or volume of contaminants through treatment.

Alternative 2 may reduce the toxicity, mobility, and volume of source area contaminants through treatment of
the suspected source materials prior to disposal; it would not reduce groundwater contamination through
treatment.
-------
Alternatives 3, 4, and 5 would reduce the toxicity, mobility, and volume of contaminants through treatment of
contaminated groundwater and possibly through treatment of the suspected source materials prior to disposal.
All three treatment alternatives would be designed to address the same mass of contaminants: the entire
groundwater contaminant plume and any source area materials reguiring treatment.

E. Short-Term Effectiveness

The short-term effectiveness of all five alternatives would be similar since the use of appropriate
engineering controls and personal protective eguipment (PPE) would be expected to minimize adverse impacts to
base residents and personnel, the local community, and workers during implementation.

Long-term monitoring, the only on-site action proposed under Alternative 1, would provide little
opportunity for short-term impact to the local community or the environment.

Alternative 2 would present a somewhat greater opportunity for short-term impacts to human health
and the environment due to excavation, handling, and decontamination of contaminated materials
from the suspected source area. Alternatives 3, 4, and 5 would present the greatest opportunity for
short-term impacts due to installation and operation of the groundwater treatment systems.

In all cases, short-term risks posed to base personnel, site workers, and the environment would be
mitigated through use of engineering controls, transportation planning, and appropriate PPE. No
permanent adverse impacts to the human health or the environment are anticipated to result from
implementation of Alternatives 2, 3, 4, or 5.

Alternative 1 would not achieve any of the RAOs. Alternative 2 would achieve all RAOs within
approximately 50 years. Alternative 3 would achieve all RAOs within approximately 45 years.
Alternative 4, with extraction wells removing groundwater from the concentrated center of the plume,
would reguire less than 45 years to achieve all RAOs. Alternative 5 would achieve all RAOs within
approximately 5 years.

F. Implementability

Each of the alternatives would be implementable. Alternative 1 is the most easily implemented since
the only activities proposed are long-term monitoring and 5-year reviews.

Alternative 2 would be the next easiest to implement because it involves only excavation and off-site
transport and disposal. There are a sufficient number of companies available with the trained personnel,
eguipment, and materials to perform excavation, disposal, and long-term monitoring. Sufficient commercial
landfill capacity is available to handle the small volume of contaminated materials (approximately 30 cubic
yards) that would reguire off-base disposal under Alternative 2.

Alternative 3 may be somewhat more difficult to implement because it would reguire installation and operation
of a new and innovative in-situ treatment technology. Reactive wall technology is available from only one
vendor, but the eguipment, materials, and personnel reguired to construct the system are available from
several sources.

Alternatives 4 and 5 would be somewhat more difficult to implement because both would reguire installation
and operation of an on-site treatment system. However, no difficulties are anticipated in implementing either
alternative because both alternatives include demonstrated technologies that employ relatively common
eguipment and materials. Several vendors are available that could provide the necessary eguipment, materials,
and services.

If additional actions are warranted, they could be easily implemented under any of the alternatives.

G. Cost

The total present-worth cost associated with each alternative is provided below for comparison. Alternative
-------
1, no action, would be the least expensive to implement and Alternative 5 would be the most expensive to
implement.

Alternative 1 $ 204,000

Alternative 2 $ 348,000

Alternative 3 $2,386,000

Alternative 4 $3,100,000

Alternative 5 $3,755,000

H. Agency Acceptance

NJDEP has had the opportunity to review and comment on all the documents in the Administrative Record and has
had the opportunity to comment on the Proposed Plan. Comments received from the NJDEP have been incorporated
into the Proposed Plan.

I. Community Acceptance

The community has had the opportunity to review and comment on documents in the Administrative Record and has
participated in regularly scheduled Restoration Advisory Board (RAB) meetings convened to encourage community
involvement. A public meeting was held to provide the community an opportunity to learn about the Proposed
Plan. The community has not indicated objections to the alternatives selected in this ROD. Part III,
Responsiveness Summary, of this ROD presents an overview of community involvement and input to the selected
alternative.

X. THE SEIiECTED REMEDY

The Navy, with the support of EPA and in consultation with NJDEP, has selected Alternative 5: Air Sparging
with Soil Vapor Extraction, Source Removal, Institutional Controls, and Long-Term Monitoring as the preferred
alternative. This alternative is in compliance with ARARs and includes a CEA as reguired by the state
groundwater guality protection criteria. It would actively mitigate the potential exposure scenarios, which
are direct exposure and consumption of contaminated groundwater from the site, and would be protective of
human health and the environment.

By utilizing air sparging with soil vapor extraction, active removal of contaminants from the soil and
groundwater would be achieved. Residual VOCs, remaining after AS/SVE treatment reaches its physically
limiting endpoint would be permitted to naturally attenuate under anaerobic conditions in-situ. Removal of
the suspected source area would eliminate the potential for direct exposure.

Although the preferred alternative employs an active treatment technology, groundwater within the plume may
not attain state groundwater criteria for approximately 5 or more years. Therefore, a classification
exception area (CEA) would need to be established in the vicinity immediately adjacent and (approximately
800-1,000 feet) downgradient of the plume area of OU-3. A formal CEA would preclude use of site groundwater
during the remediation period. Long-term monitoring would determine when criteria have been met and would
also evaluate the effectiveness of the remedial action. Long-term monitoring will be guarterly until such
time as EPA and the Navy agree on a reduced schedule. The Navy would periodically review remediation progress
with EPA and NJDEP.

The preferred alternative is believed to provide the best balance of protection among the alternatives with
respect to response criteria. It utilizes a proven technology that has shown encouraging results in similar
situations.

Based on available information, the Navy and EPA believe the preferred alternative would be protective of
human health and the environment, would be cost effective, and would be in compliance with all statutory
-------
requirements of EPA, the state, and the local community.

XI. STATUTORY DETERMINATIONS

The remedy selected for OU-3 satisfies the remedy selection requirements of CERCLA and the NCP. The remedy is
expected to be protective of human health and the environment, complies with ARARs, and is cost effective.
The followinq sections discuss how the selected remedial action addresses these statutory requirements.

A. Protection of Human Health and the Environment

Alternative 5 would be protective of both human health and the environment throuqh treatment of contaminated
qroundwater and implementation of institutional controls. Removal of the suspected source of qroundwater
contamination should facilitate the remediation of contaminated qroundwater. The effectiveness of this
alternative for interim protection of human health (until qroundwater remediation is complete) is dependent
on enforcement of institutional controls.

B. Compliance With and Attainment of ARARs

The selected remedy for OU-3 will comply with all applicable or relevant and appropriate chemical-specific,
location-specific, and action-specific ARARs. Tables 7 throuqh 12 summarize ARARs and TBCs applicable to
OU-3.

1. Chemical-Specific ARARs

Potential federal and state chemical-specific ARARs are listed in Tables 7 and 8, respectively.
Implementation of Alternative 5 would comply with the ARARs identified in Tables 7 and 8.

2. Location-Specific ARARs

Potential federal and state location-specific ARARs are listed in Tables 9 and 10, respectively. It is
expected that Alternative 5 will comply with these ARARs.

3. Action-Specific ARARs

Potential federal and state action-specific ARARs are listed in Tables 11 and 12, respectively. It is
expected that Alternative 5 will comply with these ARARs.
-------
TABLE 7
POTENTIAL FEDERAL CHEMICAL-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
REQUIREMENT
Resource Conservation and
Recovery Act (RCRA)-
Groundwater Protection Standard
(40 CFR 264.94)
STATUS
Potentially Relevant
and Appropriate
REQUIREMENT SYNOPSIS

MCLs have been promulgated for a number of common organic and
inorganic contaminants to regulate the concentration of contaminants in
public drinking water supply systems. MCLs may be relevant and
appropriate for groundwater because the aguifer beneath the site is a
potential drinking water supply.
The RCRA groundwater protection standard is established for groundwater
monitoring of RCRA permitted treatment, storage or disposal facilities. The
standard is set at either an existing or proposed RCRA-MCL, background
concentration, or an alternate concentration limit (ACL) protective of human
health and the environment.

These regulations identify hazardous wastes that are restricted from land
disposal and establish waste analysis and recordkeeping reguirements and
"treatment standards" (concentration levels or methods of treatment) that
wastes must meet in order to be eligible for land disposal.
AWQC are non-promulgated health-based surface water guality criteria that
have been developed for carcinogenic and noo-carcinogenic compounds for
the protection of human health. AWQC have also been developed for the
protection of aguatic organisms.
COMMENTS

MCLs may be used to establish clean-up levels
for the portion of the aguifer underlying OU-3.
MCLs can be used to derive potential soil clean-
up levels by the use of modeling, and possibly
sampling, to determine the potential leachability of
the compound to groundwater.

RCRA-MCLs may be used or ACLs may be
developed to identify levels of contamination in
the aguifer above which human health and the
environment are at risk and to provide an
indicator when corrective action is necessary.

Contaminated soil must be analyzed and
disposed in accordance with the reguirements of
these regulations. If necessary, soils will be
treated to attain applicable "treatment standards"
prior to placement in a landfill, or other land
disposal facility. This reguirement would be
considered for alternatives involving land
disposal.
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TABLE 7
POTENTIAL FEDERAL CHEMICAL-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
Page 2 of 3
REQUIREMENT
STATUS
REQUIREMENT SYNOPSIS
Revised Interim Soil Lead Guidance
for CERCLA Sites and RCRA
Corrective Action Facilities (QSWER
Directive No. 9355.4-12)(July 1994)
MCLGS are health-based limits for contaminant concentrations in drinking
water. MCLGs are established at levels at which no known or anticipated
adverse effects on human health are anticipated and that allow for an
adequate margin of safety. MCLGs are set without regard for cost or
feasibility.

This OSWER Directive recommends a lead soil screening level of 400 ppm
for residential land use based on the IEUBK model. The screening value
may be used to determine whether sites or portions of sites warrant further
evaluation and evaluations of risks.
If any part of the OU-3 site is to be considered for
eventual residential use, then the screening value
may be used to assess whether site-specific lead
levels reguire further evaluation and possible
remediation.
This strategy was considered in conj unction with
the Federal SDWA and State Groundwater
Protection Rules in order to determine
groundwater clean-up levels.
RBCs are developed based on estimating a concentration in a specific
media (i.e. air water or soil) that is associated with specific exposure
assumptions and a specific risk level (i.e., Hazard Quotient of or a Cancer
Risk of 1 x 10 E-6). The selection of specific exposure parameters and risk
levels also contribute to the calculated concentration.
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TABLE 7
POTENTIAL FEDERAL CHEMICAL-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
Page 3 of 3
REQUIREMENT
Clean Air Act - Standards for Air
Emissions from Municipal Solid
Waste Landfills (40 CFR 60.752 and
60.753)
STATUS
Potentially Relevant
and Appropriate
REQUIREMENT SYNOPSIS
Active landfills with design capacities equal to or greater than 2. 5 million cubic
meters are required to have landfill gas collection and control systems if greater
than 5 0 megagrams of non-methane organic compounds are expected to be
emitted. The collection system shall be operated so that the methane
concentration is less than 500 ppm above background at the surface of the
landfill.
COMMENTS

These advisories and health assessment
documents were used to assess health risks from
contaminants present at the site.

Both Sites 4 and 5 landfills are estimated to be
much less than 2 million cubic feet in capacity.
However, soil gas studies and measurement of
methane concentrations at the landfill surfaces
need to be conducted during the pre-design phase
to determine whether landfill gas controls need to
be included as part of the control systems.
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TABLE 8
POTENTIAL FEDERAL CHEMICAL-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
REQUIREMENT
STATUS

Applicable
REQUIREMENT SYNOPSIS

This regulation establishes the rules to protect ambient
groundwater guality through establishment of groundwater
protection and clean-up standards and setting of numerical
criteria limits for discharges to groundwater. The Ground Water
Criteria (GWQC)(N.J.A.C. 7:9-6.7) are the maximum allowable
pollutant concentrations in groundwater that are protective of
human health. This regulation also prohibits the discharge to
groundwater subseguently discharging to surface water that do
not comply the Surface Water Quality Standards (SWQS).
Because contaminated groundwater is present underneath QU-
3 in excess of GWQS, these regulations will be considered in
determining groundwater action levels. Application for
Classification Exception Area (CEA) may be reguired if GWQS
will not be met during the term of proposed remediation. The
CEA procedure ensures that designated groundwater uses at
remediation sites are suspended for the term of the CEA.
These standards establish rules to protect and enhance surface
water resources, define surface water classifications and uses,
and establish water-guality-based criteria and effluent discharge
limitations. The Surface Water Criteria (SWQC)(N.J.A.C. 7:9B-
14) are the maximum allowable pollutant concentrations in
surface water for the designated use.
For alternatives where surface water may be affected, remedial
measures may be needed so that the SWQC are attained in
the long term. Remedial alternatives shall consider action to
mitigate the continued contamination of surface waters.
New Jersey Safe Drinking Water Act
(N.J.A.C. 7:10)
These regulations were promulgated to assure the provision of
safe drinking water to consumers in public community water
systems. Maximum Contaminant Levels (MCLs)(N.J.A.C. 7:10-
16) have been established to regulate the concentration of
organic and metal contaminants in water supplies.
MCLs may be relevant and appropriate for groundwater because
the aguifer beneath the site is a potential drinking water supply.
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TABLE 8
POTENTIAL STATE CHEMICAL-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
Page 2 of 2

REQUIREMENT
REQUIREMENT SYNOPSIS
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TABLE 9
POTENTIAL FEDERAL LOCATION-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
REQUIREMENT
STATUS

Potentially Applicable
Potentially Applicable
REQUIREMENT SYNOPSIS
Federal agencies are required to minimize the
destruction, loss, or degradation of wetlands and
preserve and enhance natural and beneficial values
of wetlands.
Federal agencies are reguired to reduce the risk of
flood loss, minimize impact of floods, and restore and
preserve the natural and beneficial value of
floodplains.

Any RCRA facility that treats, stores, or disposes of
hazardous waste, if situated in a 100-year floodplain,
must be designed, constructed, operated, and
maintained to avoid washout.
Remedial alternatives that involve excavation or deposition
of materials will include all practicable means of minimizing
harm to the wetlands adj acent to OU-3. Wetlands
protection consideration will be incorporated into the
planning, decision-making, and implementation of remedial
alternatives.

The potential effects on floodplains will be considered during
the development and evaluation of remedial alternatives. All
practicable measures will be taken to minimize adverse
effects on floodplains.
Potentially Applicable, if
present
Potentially Applicable
Actions shall be taken to conserve endangered or
threatened species or to protect critical habitats.
Consultation with the Department of the Interior is
reguired.

This regulation reguires that any federal agency that
proposes to modify a body of water must consult with
the U.S. Fish and Wildlife Service and reguires that
actions be taken to avoid adverse effects, minimize
potential harm to fish or wildlife, and preserve natural
and beneficial uses of the land.
During the evaluation of alternatives, potential remediation
effects on the wetlands and floodplains are evaluated, if it is
determined that an impact may occur, then the U.S. Fish
and Wildlife Service, the NJDEP, and EPA would be
consulted.
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TABLE 9
POTENTIAL FEDERAL LOCATION-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
Page 2 of 2

REQUIREMENT
REQUIREMENT SYNOPSIS
Potentially Applicable, if
present
Action will be taken to recover and to preserve
scientific, prehistoric, historic, or archaeologic
artifacts that may be threatened as the result of
terrain alteration.
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TABLE 10
POTENTIAL STATE LOCATION-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
REQUIREMENT
STATUS
Potentially Applicable
Potentially Applicable
Potentially Applicable
REQUIREMENT SYNOPSIS

Regulate activities that result in the disturbance in
and around fresh water wetland areas induding
removing or dredging wetand sods, disturbing the
water level or water table, driving piles, placing of
obstructions, destroying plant life, and discharging
dredged or fill materials into open water.

This regulation reguires mitigation of the disturbed
wetlands or filled open water. Generally reguires
the restoration, creation, or enhancement of area,
or donations to the Mitigation Bank, of egual
ecological value.

These regulations control development in
floodplains and water courses that may adversely
affect the flood-carrying capacity of these features,
subj ect new facilities to flooding, increase storm
water runoff, degrade water guality, or result in
increased sedimentation, erosion, or
environmental damage.

These regulations specify siting reguirements and
limitations for commercial hazardous waste
facilities including protection of nearby residents,
surface water, groundwater, air, and
environmentally sensitive areas.
If a remedial attentative action results in the loss of
wetlands through dredging, filling, or construction
activities, then mitigation measures will need to be
incorporated into the alternative's design.
This reguirement is applicable to remedial
alternative actions that may adversely affect
floodplains adjacent to OU-3.
If remedial alternatives employs an on-site or on
base treatment of contaminated soils, sediments,
or materials, then remediation activities will need
to be consistent with these reguirements.
-------
REQUIREMENT

Resource Conservation and Recovery
Act (RCRA) - Hazardous Waste
Generator and Transporter
Requirements (40 CFR parts 262 and
263)
TABLE 11
POTENTIAL FEDERAL ACTION-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
STATUS

Potentially
Applicable
Potentially
Applicable
Potentially
Applicable
REQUIREMENT SYNOPSIS

These regulations establish the responsibilities of generators
and transporters of hazardous waste in the handling,
transportation, and management of waste. The regulations
specify the packaging, labeling, recordkeeping, and manifest
requirements.
Outlines requirements for safety equipment and spill control.
If a remedial alternative includes the establishment of an on-base
treatment facility for hazardous wastes (characteristic or listed),
then this regulation will be considered. This regulation specifies
TSD facilities construction, fencing, postings, and operations. All
workers will be property trained. Process wastes will be evaluated
for the characteristics of hazardous wastes to assess further
handling requirements.

If a remedial alternative includes treatment, storage, or disposal of
hazardous wastes, then this regulation will be considered. Safety
and communication equipment will be maintained at the site.
Local authorities will be familiarized with the site operations.
Potentially
Applicable
Potentially
Applicable
If the alternative includes treatment, storage, or disposal of
hazardous wastes, then records of facility activities will be
developed and maintained during remedial actions.
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TABLE 11
POTENTIAL FEDERAL ACTTION-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
Page 2 of 2
REQUIREMENT
STATUS
REQUIREMENT SYNOPSIS
Potentially
Relevant and
Appropriate
Details specific requirements for closure and post-closure of
municipal solid waste landfills. Final cover requirements that
address minimizinq infiltration and erosion are identified in this
requlation.
RCRA - Land Treatment
(40 CFR 265 Subpart M)
Potentially
Applicable
Followinq closure, post-closure requirements include
preparinq a post-closure plan, maintaininq inteqrity and
effectiveness of the final cover, qroundwater monitorinq, and
maintaininq and operatinq a qas collection system.
RCRA - Thermal Treatmnent(40 CFR
265 Subpart P)
Potentially
Applicable
Alternatives that include thermal or catalytic oxidation of offqases
would be desiqned and operated in compliance with this
requlation.
Potentially
Applicable
RCRA - Air Emission Standards for
Process Vents
(40 CFR 265 Subpart AA)
Potentially
Applicable
This requlation contains air pollutant emission standards fix
process vents, dosed-vent systems, and control devices at
hazardous waste TSD facilities. This subpart applies to
equipment associated with solvent extraction or air/steam
strippinq operations that treat wastes that are identified or
listed RCRA hazardous wastes and have a total orqanics
concentration of 10 ppm or qreater.
These standards will be considered durinq the development and
desiqn of alternatives that include treatment of VOC-contaminated
soils. Air emissions from treatment units will be monitored to
ensure compliance with this ARAR.
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TABLE 12
POTENTIAL STATE ACTION-SPECIFIC ARARs AND TBCs
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
REQUIREMENT
REQUIREMENT SYNOPSIS
Potentially
Applicable
These regulations establish the responsibilities of generators
and transporters of hazardous waste in the handling,
transportation, and management of waste. The regulations
specify the packaging, labeling, recordkeeping, and manifest
reguirements.
New Jersey Thermal Treatment
Regulations
(N.J.A.C. 7:26-11.6)
Potentially
Applicable
Potentially
Relevant and
Appropriate
Potentially
Applicable
These regulations identify reguirements for facilities in
general, groundwater monitoring, preparedness and
prevention, contingency and emergency procedures, and
general closure and post-closure.

Details specific reguirements for closure and post-closure of
municipal solid waste landfills. Final cover reguirements that
address minimizing infiltration and erosion are identified in this
regulation.

Following closure, post-closure reguirements include
preparing a post-closure plan, maintaining integrity and
effectiveness of final cover, groundwater monitoring, and
maintaining and operating a gas collection system.

These regulations detail operating reguirements, waste
analyses and monitoring of treatment conditions, performance
standards, and closure of existing facilities that thermally treat
hazardous wastes.
If a remedial alternative includes the establishment of an on-base
treatment facility for contaminated soils and materials, then this
regulation will be compiled with during implementation.
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TABLE 12
POTENTIAL STATE ACTION-SPECIFIC ARARS AND TBCS
FEASIBILITY STUDY
NAVAL WEAPON STATION EARLE, COLTS NECK, NEW JERSEY
Page 2 of 2
REQUIREMENT
New Jersey Control and

Prohibition of Air Pollution by

Toxic Substances

(NJAC. 7:27-17)
Potentially
Applicable
Potentially
Applicable
REQUIREMENT SYNOPSIS

These regulations detail operating reguirements, waste
analyses and monitoring of treatment conditions, and closure
of existing facilities that physically, chemically, or biologically
treat hazardous wastes. Also governs handling and
compatibility of wastes in treatment processes.

These regulations govern the emission of Group I and Group
II toxic volatile organic compounds (TXS) to the ambient air.
Group I TXS would be addressed through adeguate stack
height or prevention of aerodynamic downwash. Group II
TXS would be addressed through reasonably available control
technology.
Alternatives that my result in the release of Group I or Group II
TXS to the ambient air, exceeding 0.1 Ib/hr, would incorporate
appropriate vapor control measure to comply with these
reguirements.
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4. To Be Considered (TBC) Standards

Tables 7 through 12 summarize TBCs applicable to OU-3. It is expected that Alternative 5 will comply with
these TBCs. The most stringent reguirements among the TBCs are found in the GWQSs, MCLs, or risk-based
criteria. In the case where a risk-based criterion is selected as a remediation goal, multiple routes of
exposure (ie., exposure from ingestion of drinking water and inhalation of vapors while showering) and
adjustments appropriate to reflect exposure to multiple chemicals with the same effect must be considered.
Table 13 presents the preliminary remediation goals (PRGs) for Site 26.

C. Cost-Effectiveness

The Navy and EPA have determined that the selected remedy for OU-3 is cost effective in that it mitigates
the risks posed by the site-related contaminants, meets all other reguirements of CERCLA, and affords
overall effectiveness proportionate to the cost. The capital costs for Alternative 5 total $1,698,000. The
average annual O&M costs are $499,000, and 5-year reviews cost $15,500 per event. Over a 30-year period, the
net present-worth cost is $3,755,000 (at a seven percent discount rate).

D. Utilization of Permanent Solutions and Alternative Treatment Technologies to the
Maximum Extent Practicable

The Navy and EPA have determined that the selected remedy represents the maximum extent to which permanent
solutions and alternative treatment technologies can be utilized in a cost-effective manner at OU-3.

E. Preference for Treatment as a Principal Element

The Navy and EPA have determined that the selected remedy represents the maximum extent to which permanent
solutions and treatment technologies can be utilized in a cost-effective manner at OU-3.
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Contaminant of
Concern
Trichloroethene
1,1-Dichloroethen
1,2-Dichloroethene
(cis/trans)
Benzene
Carbon
tetrachloride
Tetrachloroethene
Cadmium
TABIiE 13
SITE 26 GROUNDWATER PRELIMINARY REMEDIATION GOALS (Ig/L)
NAVAL WEAPONS STATION EARLE, COLTS NECK, NEW JERSEY
ARARS
NJ GWQS
1
10
70/100

0.2
0.4

1
4
SDWA PRG (2)
MCLs Based on
Risk = 1E-6
[carcinogen]
5
7
70/100

5
5
3.65
0.11
PRG (2)
Based on
HI = 0.1
[non-carcinogen]

8.45

13.3
Maximum Maximum
Background Detected Site
Concentration Cone.
BDL
BDL
BDL

BDL
BDL

BDL
1.9
4800 (1)
5 (1)
2000

11 (1)
2 (1)

5 (1)
4.4(3)
Notes:
(1)
(2)
(3)
New Jersey State Ground Water Quality Standards (GWQS) are ARARs.
Safe Drinking Water Act (SDWA) Maximum Contaminant Levels regulate organic and Inorganic constituents in public drinking water supplies, and are presented
here only for comparison purposes.
not a COG under this parameter.
BDL Below derection limit.
Based on direct push sampling with field GC analysis.
PRG numerical values for carcinogens and non-carcinogens are based on exposure scenarios and factors applied in the NWS Earle human health risk assessment.
Cadmium maximum site detected concentration of 4.4 (average site-related concentration of 1.04) is statistically considered to be egual to the PRG.
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RECORD OF DECISION
NAVAL WEAPONS STATION EARLE
OPERABLE UNIT 3

PART III - RESPONSIVENESS SUMMARY

The purpose of this Responsiveness Summary is to review public response to the Proposed Plan for OU-3. It
also documents the consideration of comments during the decision-making process and provides answers to any
comments raised during the public comment period.

The Responsiveness Summary for OU-3 is divided into the following sections:

• Overview - This section briefly describes the remedial alternative recommended in the Proposed
Plan and any impacts on the Proposed Plan due to public comment.

• Background on Community Involvement - This section describes community relations activities
conducted with respect to the area of concern.

• Summary of Major Questions and Comments - This section summarizes verbal and written comments
received during the public meeting and public comment period.

I. OVERVIEW

This Responsiveness Summary addresses public response to the Proposed Plan. The Proposed Plan and other
supporting information were maintained for public review in the Administrative Record file for OU-3, which
was maintained at the Monmouth County Library (Eastern Branch) in Shrewsbury, New Jersey.

II. BACKGROUND ON COMMUNITY INVOLVEMENT

Throughout the investigation period, EPA and NJDEP reviewed work plans and reports and provided comments and
recommendations that were incorporated into appropriate documents. A Technical Review Committee (TRC),
consisting of representatives from the Navy, EPA, NJDEP, the Monmouth County Health Department, and other
agencies and local groups surrounding NWS Earle, was formed. The TRC later was transformed into the
Restoration Advisory Board (RAB) to include community members as well as the original officials from the TRC.
The RAB has been holding periodic meetings to maintain open lines of communication with the community and to
inform all parties of current activities.

On January 3, 1998 and January 4, 1998, a newspaper notification inviting public comment on the Proposed Plan
appeared in the Asbury Park Press. The public notice summarized the Proposed Plan and the preferred
alternative. The announcement also identified the time and location of the public meeting and specified a
public comment period as well as the address to which written comments could be sent. Public comments were
accepted from December 19, 1997 to January 30, 1998. The newspaper notification also identified the Monmouth
County Library as the location of the Administrative Record.

The public meeting was held on January 22, 1998 from 7:00 p.m. in Building C-54 at NWS Earle, Colts Neck, New
Jersey. At this meeting, representatives from the Navy, EPA, and the NJDEP were available to answer questions
concerning OU-3 and the preferred alternative. The complete attendance list is included in Appendix B.

III. SUMMARY OF MAJOR QUESTIONS AND COMMENTS

A. Written Comments

During the public comment period from December 19, 1997 to January 30, 1998, no written comments were
received from the public pertaining to OU-3. No new comments were received from the NJDEP or EPA.

B. Public Meeting Comments
-------
Numerous comments concerning OU-3 were received at the joint RAB meeting and public meeting to discuss the
OU-3 Proposed Plan held on January 22, 1998. The following is a summary of comments/questions and government
response.

Greg Goepfert and John Mayhew initiated discussion by giving a summary of site conditions and the proposed
plan of remediation.

QUESTION: Ben Forest asked, Do the wells go across the water table?

REPSPONSE: Currently, all wells terminate above the clay layer.

As part of the remedial investigation, a narrow diameter sampling tool was used to obtain samples from
beneath the clay layer. Contaminant concentrations in these samples were orders of magnitude lower than above
the clay layer. All of the narrow diameter punch holes made through the clay layer during remedial
investigation were sealed after sample collection, using low-permeability material (bentonite/cement grout)
to avoid the possibility of leaving a conduit for contamination to spread to below the clay layer.

The conceptual design for remediation is for the air sparge injection wells to terminate above the clay
layer. There is no plan to install wells through the barrier clay layer. Since the highest concentrations are
directly above the clay, the sparge well screens will intersect the top of the clay.

QUESTION: Lester Jargowsky asked, Are there vapor treatment units? What kind of technology do we have there?

RESPONSE: Right now, the Navy anticipates that vapor treatment for air sparging gases will be needed. These
systems vary in design, and partially will depend on the level of natural degradation that may occur in the
ground after the system is installed and running.

COMMENT: Lester Jargowsky stated, Air sparging is not a new technology. There are leaking underground storage
tank sites in the county where this technology is currently used.

RESPONSE: Agree.

QUESTION: Larry Harris asked, What is the radius of effectiveness?

RESPONSE: The first step, before full-scale design, is to install a couple of sparge points to measure the
radius of influence by analyzing soil characteristics and measuring pressure changes. This "pilot" operation
will provide the design parameters needed to extend the system based on measured criteria rather than by
trial and error. The Navy anticipates that the sandy soil will result in a fairly wide radius of influence.

QUESTION: Kevin Bova asked, Is the injected air tempered?

RESPONSE: Designs vary. No decision on tempering the sparge air has been made.

QUESTION: Ben Forest asked, Is the Navy committed to operating this base for a long-term basis? There has
been talk of base closing.

RESPONSE: The NWS Earle Commanding Officer stated that there is no discussion of shutting down NWS Earle at
any time that involves our lifetime.

QUESTION: Ben Forest asked, Has there been any testing done outside of the base to see if there's been
migration of contaminants outside the base into Colts Neck?

RESPONSE: As part of the remedial investigation, at the reguest of EPA, every stream leaving NWS Earle was
sampled. Surface water and sediments were sampled and analyzed. Also, no sites were found with chlorinated
solvents in groundwater moving off site.

QUESTION: Ben Forest said, More specifically, when we read that report, we didn't see any reference to
-------
groundwater, well water (off-station).

RESPONSE: Some off-station groundwater studies in wells have been made by the health department (with no
detection of compounds thought to originate at Earle). In general, of all the sites at NWS Earle, at only a
few of them have we seen solvent contamination. At this site (Site 26), surely the area of most significant
impact found in this remedial investigation, the extent of the contamination plume in groundwater was found
by going in with the hydropunch sampling tool which allows for a high degree of pinpointing the sample
location (and hence the contaminant gradient). Using the hydropunch technigue we followed the migration
pathway of the contamination plume to the leading edge, the area where the concentration falls off to
non-detect. There is no reason to believe that the contaminant plume would or could extend beyond where the
concentration in the leading edge of the plume falls off to non-detect. The leading edge of the Site 26
contaminant plume is thousands of feet from the nearest NWS Earle property boundary. The remedial
investigation generally concentrated on obtaining information at areas of known impact and was expanded to
define the extent of impact. The streams leaving the base were then sampled to see if any of the compounds
from any site were migrating with groundwater to surface water. The stream sample results were at non-detect
levels (for these compounds).

COMMENT: Lester Jargowsky said, Early in the remedial investigation, we (the RAB or it's predecessor the
Technical Review Committee [TRC]) asked the Navy to start off by performing a full analysis of water and
sediment on every stream leaving the base. We wanted to be comfortable from the beginning that nobody was
being harmed. The results were very favorable. However, a hazardous waste site unrelated to the base, a
furniture stripping business using solvents, is located near NWS Earle. This site is really close to Earle
but it has nothing to do with Earle.

RESPONSE: Comment noted.

COMMENT: Ben Forest said he had some comments but they weren't written for submission.

RESPONSE: Comments can be taken as part of the meeting minutes. That is the reason for the meeting tonight.

COMMENT: Ben Forest said, I would say that we were basically pleased with what we saw there (in the Site 26
Proposed Plan). Bear in mind that we're laymen on this, not engineers, but we noticed that you went for the
most comprehensive option, alternative five as I remember. Basically, I'm sure everyone would agree, we're
also concerned whether Earle stays open or not. Maybe things beyond your control may change things, who
knows? We're pleased that you're going with the most aggressive approach to that (Site 26 remediation).

The other thoughts. We were just really surprised. To be honest with you, I'm cynical after dealing with the
government, good and bad experiences. I was expecting that you would go for alternative two or the less
aggressive approaches. I was very pleased to see that you went with the most aggressive approach, and I
thought it was unusual and was very happy to see it.

RESPONSE: The Navy originally was looking at the reactive wall alternative. Everything we looked at said it
(the reactive wall alternative) would be protective of the surrounding environment. The immediate area would
remain impacted for 30 or 40 years although the surrounding environment would be protected. The EPA, in
particular, had some concerns about the lengthy time frame. With air sparging (alternative five), we can go
in and get a lot of VOC mass removal rapidly. There may still be 30 or 40 years before there is no impact
from the site, but the advantage is that much of the volume of the VOC contamination can be removed early in
the period. So, through some discussions with EPA, and having brought it up at a couple of RAB meetings, we
changed our decision on how we wanted to treat this site, and went with the air sparging approach.

One of EPA's concerns was that Earle could close down and some other (less controlled) use may be desired.
Base closure is not anticipated, but once something (waste contamination) is removed, we don't have to worry
about it any longer.

COMMENT: Ben Forest said, You said that you did some testing below the clay line. We would like to see that
done as a precaution. It certainly sounds like it is not necessary.
-------
REPLY: Agree. That testing has been done as we discussed earlier. Our approach in taking these samples below
the confining clay layer, when there was something (VOCs) above the clay layer with a chance for leakage
right at well points, was to avoid having any permanent intrusion through the clay layer. That is why we are
trying to focus on top of the clay layer once we took initial samples showing it (the area below the clay
layer) wasn't already impacted.

COMMENT: Ben Forest said, The other thought (was), we didn't see anything in the Proposed Plan about testing
beyond the borders of the base, although I gather there has been some testing done in regards to the various
issues at Earle. You know, just as a precaution.

REPLY: Agree. The base-wide stream sampling program discussed earlier was performed to help cover this
concern, and site-related contamination was investigated to the limits of migration as discussed earlier.

COMMENT: Ben Forest said, Thank you for your patience.

REPLY: NWS Earle Commanding Officer, Captain Honey, said, The Navy is very committed to the remediation
process at all of our sites. I think you'll see that in some of the other site remediations we've done, or
are in the process of doing, the extent to which we go. We don't take short cuts in the process. It's a
guality effort all around.

QUESTION: Sharon Brown asked, What is the duration of the soil vapor extraction phase?

REPLY: Every year the progress will be evaluated.

QUESTION: Sharon Brown clarified the guestion, I mean the anticipated duration.

REPLY: The proposed plan estimated that five years may be reguired for the active air sparging phase. When we
put together the estimates, we don't want to be too optimistic because time estimates affect the total cost
that may be needed for funding. However, we think that the time frame may be much less than five years
because we have conditions that are favorable to air sparging. In order to make a fair comparison among the
different options, we want to say this process could take up to five years. It is very unlikely it would take
longer than that. There is a good chance it will take a shorter duration.
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Appendix A
TERMS USED IN THE RECORD OF DECISION

1,2-Dichloroethene (1,2-DCE): Common volatile organic solvent formerly used for cleaning, degreasing, or
other useds in commerce and industry.

Applicable or Relevant and Appropriate Reguirements (ARARs): The federal and state reguirements that a
selected remedy must attain. These reguirements may vary among sites and remedial activities.

Administrative Record: An official compilation of site-related documents, data, reports, and other
information that are considered important to the status of and decisions made relative to a Superfund site.
The public has access to this material.

Carcinogenic: A type of risk resulting from exposure to chemicals that may cause cancer in one or more
organs.

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA): A federal law passed in 1980
and modified in 1986 by the Superfund Amendments and Reauthorization Act (SARA). The Act created a trust
fund, known as Superfund, to investigate and clean up abandoned or uncontrolled hazardous substance
facilities.

Feasibility Study (FS): Report identifying and evaluating alternatives for addressing the contamination
present at a site or group of sites.

Groundwater Quality Standards (GWQS): New-Jersey-promulgated groundwater guality reguirements, N.J.A.C.
7:9-6.

Hazard Index (HI): The sum of chemical-specific Hazard Quotients. A Hazard Index of greater than 1 is
associated with an increased level of concern about adverse non-cancer health effects.

Hazard Quotient (HQ): A comparison of the level of exposure to a substance in contact with the body per unit
time to a chemical-specific Reference Dose to evaluate potential non-cancer health effects. Exceedence of a
Hazard Quotient of 1 is associated with an increased level of concern about adverse non-cancer health
effects.

Initial Assessment Study (IAS): Preliminary investigation usually consisting of review of available data and
information of a site, interviews, and a non-sampling site visit to observe areas of potential waste disposal
and migration pathways.

Land Disposal Restrictions (LDRs): A set of EPA-prescribed limit concentrations with associated treatment
standards regulating disposal in landfills.

Maximum Contaminant Level (MCL): EPA-published (promulgated as law) maximum concentration level for compounds
found in water in a public water supply system.

Noncarcinogenic: A type of risk resulting from the exposure to chemicals that may cause systemic human health
effects.

National Contingency Plan (NCP): The basis for the nationwide environmental restoration program known as
Superfund; administered by EPA under the direction of the U.S. Congress.

National Priorities List (NPL) : EPA's list of the nation's top-priority hazardous substance disposal
facilities that may be eligible to receive federal (EPA ) money for response under CERCLA. As a federal
facility, NWS Earle is not eligible for EPA funding.

RCRA Subtitle D facility: Municipal-type waste disposal facility (landfill) regulated by the Resource
Conservation and Recovery Act (RCRA).
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Record of Decision (ROD): A legal document that describes the remedy selected for a Superfund facility, why
the remedial actions were chosen and others not, how much they are expected to cost, and how the public
responded.

Reference Dose (RD): An estimate (with an uncertainty spanning an order of magnitude or greater) of a daily
exposure level for the human population, including sensitive subpopulations, that is likely to be without an
appreciable risk of deleterious effects during a lifetime.

Remedial Action Objective (RAO): An objective selected in the FS, against which all potential remedial
actions are judged.

Remedial Investigation (RI): Study that determines the nature and extent of contamination at a site.

Site Inspection (SI): Sampling investigation with the goal of identifying potential sources of contamination,
types of contaminants, and potential migration of contaminants. The SI is conducted prior to the RI.

Semivolatile Organic Compounds (SVOCs): Organic chemicals [e.g., phthalates or polycyclic aromatic
hydrocarbons (PAHs)] that do not readily evaporate under atmospheric conditions.

Target Compound List/Target Analyte List (TCL/TAL): List of routine organic compounds (TCL) or metals (TAL)
included in the EPA Contract Laboratory Program.

Toxicity Characteristic Leaching Procedure (TCLP): Analytical test prescribed by EPA to determine potential
leachate toxicity in materials; commonly used to determine the suitability of a waste for disposal in a
landfill.

Trichloroethene (TCE): Common volatile organic solvent formerly used for cleaning, degreasing, or other uses
in commerce and industry.

Volatile Organic Compounds (VOCs): Organic liguids [e.g., vinyl chloride or trichloroethene (TCE)] that
readily evaporate under atmospheric conditions.
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APPENDIX B
ATTENDANCE LIST
JANUARY 22,1998 PUBLIC MEETING

NAME ORGANIZATI ON

Robert M. Honey Commanding Officer, NWS Earle
Gregory J. Goepfert NWS Earle
John Kolicius Naval Facilities Engineering Command
Gus Hermann! NWS Earle
Kevin M. Bova NWS Earle
Dennis Blazak NWS Earle
Deborah Sciascia NWS Earle
Mike Brady NWS Earle
Robert Jones COMSUBGRU II (U. S. Navy)
Russell Turner Brown & Root Environmental
Sharon Jaffess USEPA Region II
Robert Marcolina NJDEP
John Mayhew Naval Facilities Engineering Command
Ben Forest Monmouth Co. Friends of Clear Water
Lester Jargowsky Monmouth County Health Department
Greta Deirocini Naval Facilities Engineering Command
Sharon Brown Resident, Tinton Falls
Tim Kinsella Birdsall Engineering
Zach Lewis Birdsall Engineering
Jeff Stem Monmouth Co. Environmental Coalition
Mary Lanko Resident, Howell Township
Larry Harris Colts Neck Board of Health
Marilyn Boak Colts Neck Board of Health
Mike Heffron Foster Wheeler Corporation
Will Stephan Resident, Howell Township
Janet Coakley Resident, Howell Township
Carl Tippman Foster Wheeler Corporation

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ROD FACT SHEET
SITE
Name : Naval Weapons Station Earle
Location/State : 201 Highway 34 South, Col ts Neck, NJ
EPA Region : Region II
HRS Score (date): 37.21 (8/30/90)
Site ID # : NJ070022172

ROD
Date Signed: 9/29/98
Remedy/ies: air sparging with soil vapor extraction
Operating Unit Number: OU-3
Capital cost: $1,698,000 (in 1999 dollars)
Construction Completion: Est. Oct. 2003
0 & M per year: $ 499,000 (in 1999 dollars)
Present worth: $3,755,000 (7% discount rate and 5 years
0 & M assumed)

LEAD
EPA Enforcement*
Primary contact: Jessica Mollin (212-637-3921)
Secondary contact: Bob Wing (212-637-4332)
Main PRP(s): Naval Weapons Station Earle (NWSE)
PRP Contact: John Kolicius (610-595-0567 ext. 157)

*Note: NWSE is the remediation lead since they are a federal facility

WASTE
Type: Solvents
Medium: soil and groundwater
Origin: dumping and spills
Est. guantity: unknown
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