United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R02-93/215
September 1993
PB94-963828
f/EPA Superfund
Record of Decision
Naval Air Engineering Center
(Operable Unit 15), NJ
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50272-101
REPORT DOCUMENTATION
PAGE
1. REPORT NO.
EPA/ROD/R02-93/215
3. Recipient's Accession No.
4. Title and Subtitle
SUPERFUND RECORD OF DECISION
Naval Air Engineering Center (Operable Unit 15) , NJ
Fifteenth Remedial Action
5. Report Date
09/27/93
6.
7. Author(s)
8. Performing Organization Rapt. No.
9. Performing Organization Name and Address
10 Project Task/Work Unit No.
11. Contraet(C) or Qrant(G) No.
(C)
(G)
12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report & Period Covered
800/800
14.
IS. Supplementary Notes
PB94-963828
16. Abstract (Limit: 200 words)
\
The Naval Air Engineering Center (Operable Unit 15) site is an inactive sanitary
landfill, which is part of the 7,400-acre Naval Air Warfare Center Aircraft Division
located in Lakehurst, Ocean County, New Jersey, approximately 14 miles inland from the
Atlantic Ocean. Land use in the area is predominantly undeveloped woodlands and open
areas and light commercial and industrial areas, with the closest residential area, the
Borough of Lakehurst, located so'utheast of the facility. The Naval Air Engineering
Center (NAEC), which lies within the Toms River Drainage Basin, contains over 1,300
acres of flood-prone areas. The estimated 65,400 people who reside in the vicinity of
NAEC, use municipal wells to obtain their drinking water supply. Some private wells
exist, but these are used primarily for irrigation purposes. In 1916, Eddystone
Chemical Company leased the property to develop an experimental firing range for
testing chemical artillery shells. In 1919, the U.S. Navy assumed control of the
property, and it was formally commissioned Naval Air Station (NAS) Lakehurst in .1921.
In 1974, the NAEC was moved from the Naval Base in Philadelphia to NAS Lakehurst. The
NAEC's mission is to conduct research, development, engineering, testing and systems
integration, limited production, and procurement for aircraft and airborne weapons
systems. Historically, various operations at NAEC have required the use, handling,
(See Attached Page)
17. Document Analysis a. Descriptors
Record of Decision - Naval Air Engineering Center (Operable Unit 15) , NJ
Fifteenth Remedial Action
Contaminated Medium: None
Key Contaminants: None
b. Identifiers/Open-Ended Terms
c. COSATI Field/Group
18. Availability Statement
19. Security Class (This Raport)
None
20. Security Class (This Page)
None .
21. No. of Pages
28
22. Price
(See ANSI-Z39.18)
Sff Instructions on Rtverae
OPTIONAL FORM 272 (4-77)
(Formerly NTIS-35)
Department of Commerce
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EPA/ROD/R02-93/215
Naval Air Engineering Center (Operable Unit 15), NJ
Fifteenth Remedial Action
Abstract (Continued)
storage, and occasional onsite disposal of hazardous substances. During the operational
period of the facility, there were reported and suspected releases of these substances
into the environment. The Department of Defense's Installation Restoration Program (IRP)
has identified 44 potentially-contaminated sites at NAEC, 16 of which have warranted
further investigation to assess potential impacts. IRP investigations revealed ground
water contamination at the former sanitary landfill (Site 31). Site 31 is located in Area
D, southwest of the installation golf course and Galloway Road. The 34-acre landfill
operated from 1960 until 1980; when the landfill was closed it was capped with 6 inches of
topsoil. During its 20 years of operation the landfill received trash and garbage from
the entire facility. Potentially hazardous materials including solvents, hydraulic fluid,
oils, asbestos, and debris contaminated with pesticides, PCBs, and other organic
materials, were also reportedly disposed of at the site. Between 1981 and 1984, under the
direction of the Navy, seven monitoring wells were installed and sampling was conducted
around the perimeter of Site 31. These investigations indicated the presence of VOCs in
the ground water downgradient of the site. Subsequent investigations, conducted from 1986
to 1992, confirmed the presence of VOCs in the ground water as well as low levels of other
organic compounds. These investigations also indicated that the plume of VOC
contamination had migrated from the former landfill to the site boundary. An assessment
of the potential threat to human and health and the environment was conducted for
contaminants in the ground water downgradient of Site 31. This assessment revealed that
the levels of organic contaminants in the ground water do not pose a risk to human health
or the environment. Previous 1991 and 1992 RODs addressed OUs 1, 2, 3, and 4; and OUs 5,
6, and 7, respectively. This ROD addresses any ground water contamination at Site 31, as
OU15. Other 1993 RODs address OUs 8, 9, 10, 11, 12, 13, 14, 22, and 23. EPA has
determined that, based on the results of health assessment, the site does not present a
threat to human health or the environment and that no cleanup activities are required at
this site; therefore, there are no contaminants of concern affecting this site.
The selected remedial action for this site is no further action with ground water
monitoring. EPA has determined that conditions at the site pose no risk to human health
or the environment; however, a five year monitoring plan will be implemented to ensure
continued compliance with ground water standards and to monitor the risk to human health
and the environment. The estimated present worth cost for this remedial action is
$509,000, which includes an estimated annual O&M cost of $99,000 for 5 years.
PERFORMANCE STANDARDS OR GOALS:
Not applicable.
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ROD FACT SHEET
SITE
Name :
Location/State :
EPA Region :
HRS Score (date):
NAWC Lakehurst
Lakehurst, New Jersey
II
49.48 (July 22, 1987)
ROD
Date Signed:
Remedy:
Operating Unit Number:
Capital cost:
Construction Completion:
O & M in 1994:
1995:
1996:
1997:
1998:
Present worth:
September 27, 1993
No Action w/ground water monitoring
OU-15 (Site 31)
$13,500
N/A
$99,000
$99,000
$99,000
$99,000
$99,000
$509,500
LEAD
Enforcement
Federal Facility
Primary contact
Secondary contact
Main PRP
PRP Contact
Jeffrey Gratz (212) 264-6667
Robert Wing (212) 264-8670
U.S. Navy
Lucy Bottomley (908) 323-2612
WASTE
Type
Medium
Origin
Est. quantity
volatile organics
ground water
landfill leachate
diffuse - N/A
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LAKEHURST
RECORD OF DECISION
FOR
SITE 31
NAVAL AIR WARFARE CENTER
AIRCRAFT DIVISION
LAKEHURST, NEW JERSEY
September 14, 1993
93-09-10
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RECORD OF DECISION
DECLARATION
SITE 31
NAVAL AIR WARFARE CENTER
AIRCRAFT DIVISION
LAKEHURST, NEW JERSEY
FACILITY NAME AND LOCATION
Naval Air Warfare Center
Aircraft Division
Lakehurst, New Jersey 08733
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected action for one site
(Site 31), located at the Naval Air Warfare Center, Aircraft
Division (NAWCADLKE) in Lakehurst, New Jersey (Figure 1) . The
selected remedial action was chosen in accordance with the
Comprehensive Environmental Response, Compensation and Liability
Act (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act (SARA), and, to the extent practicable, the
National Oil and Hazardous Substances Pollution Contingency Plan.
This decision is based on the Administrative Record for these
sites, which is available for public review at the Ocean County
Library, 101 Washington Street, Toms River, New Jersey.
Both the United States Environmental Protection Agency (USEPA),
Region II Acting Administrator, and the Commissioner of the New
Jersey Department of Environmental Protection and Energy (NJDEPE)
concur with the selected remedy.
DESCRIPTION OF THE SELECTED REMEDY
The United States Department of the Navy, the lead agency for this
site, has selected the "no action with grpundwater monitoring"
alternative for Site 31.
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DECLARATION STATEMENT
The United States Department of the Navy and the United States
Environmental Protection Agency have determined that no remedial
action is necessary at Site 31 to ensure protection of human health
and the environment.
This Record of Decision addresses Site 31. The location of the
site within NAWCADLKE is shown in Figure 2. Other areas of concern
at NAWCADLKE have been or will be the subject of separate studies
and Records of Decision.
/3
Captain LeroyFarr (Date)
Commanding Officer
Naval Air Warfare Center -
Aircraft Division
Lakehurst, New Jersey
With the concurrence of:
William J.yftus'zfyX^i, P.E. (Datfe)
Acting Re^ionalA?Wministrator
U.S. Environmental Protection Agency
Region II
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SITE DESCRIPTION
NAWCADLKE is located in Jackson and Manchester Townships, Ocean
County, New Jersey, approximately 14 miles inland from the Atlantic
Ocean (Figure 1). NAWCADLKE is approximately 7,400 acres and is
bordered by Route 547 to the east, the Fort Dix Military
Reservation to the west, woodland to the north (portions of which
are within Colliers Mills Wildlife Management Area), Lakehurst
Borough and woodland, including the Manchester Wildlife Management
Area, to the south. NAWCADLKE and the surrounding area are located
within the Pinelands National Reserve, the most extensive
undeveloped land tract of the Middle Atlantic Seaboard. The
groundwater at NAWCADLKE is classified by NJDEPE as Class I-PL
(Pinelands).
NAWCADLKE lies within the Outer Coastal Plain physiographic
province, which is characterized by gently rolling terrain with
minimal relief. Surface elevations within NAWCADLKE range from a
low of approximately 60 feet above mean sea level in the east-
central part of the base, to a high of approximately 190 feet above
mean sea level in the southwestern part of the base. Maximum
relief occurs in the southeastern part of the base because of its
proximity to the more rolling terrain of the Inner Coastal Plain.
Surface slopes are generally less than five percent.
NAWCADLKE lies within the Toms River Drainage Basin. The basin is
relatively small (191 square miles) and the residence time for
surface drainage waters is short. Drainage from NAWCADLKE
discharges to the Ridgeway Branch to the north and to the Black and
Union Branches to the south. All three streams discharge into the
Toms River. Several headwater tributaries to these branches
originate at NAWCADLKE. Northern tributaries to the Ridgeway
Branch include the Elisha, Success, Harris and Obhanan Ridgeway
Branches. The southern tributaries to the Black and Union Branches
include the North Ruckles and Middle Ruckles Branches and the
Manapaqua Brook. The Ridgeway and Union Branches then feed Pine
Lake; Located approximately 2.5 miles east of NAWCADLKE before
joining Toms River. Storm drainage from NAWCADLKE is divided
between the north and south, discharging into the Ridgeway Branch
and Union Branch, respectively. The Paint Branch, located in the
east-central part of the base, is a relatively small stream which
feeds the Manapagua Brook.
Three small water bodies are located in the Western portion of
NAWCADLKE: Bass Lake, Clubhouse Lake, and Pickerel Pond.
NAWCADLKE also contains over 1,300 acres of flood-prone areas,
occurring primarily in the south-central part of the base, and
approximately 1,300 acres of prime agricultural land in the western
portion of the base.
There are 913 acres on the eastern portion of NAWCADLKE that lie
within Manchester Township and the remaining acreage is in Jackson
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NAVAL AIR WARFARE CENiER .
AIRCRAFT DIVISION, LAKEHURSi
&ND NEIGHBORING PROPERilES
FIGURE 1 - LOCATION MAP
A.
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Township. The combined population of Lakehurst Borough, Manchester
and Jackson Townships is approximately 65,400, for an area of
approximately 185 square miles. The average population density of
Manchester and Jackson Townships is 169 persons per square mile.
The areas surrounding NAWCADLKE are, in general, not heavily
developed. The closest commercial area is located near the
southeastern section of the facility in the borough of Lakehurst.
This is primarily a residential area with some shops but no
industry. To the north and south are State wildlife management
areas which are essentially undeveloped. Adjacent to and south of
NAWCADLKE are commercial cranberry bogs, the drainage from which
crosses the southeast section of NAWCADLKE property.
For the combined area of Manchester and Jackson Townships,
approximately 41 percent of the land is vacant (undeveloped) , 57
percent is residential, one percent is commercial and the remaining
one percent is industrial or farmed. For Lakehurst Borough, 83
percent of the land is residential, 11 percent is vacant and the
remaining 6 percent commercially developed.
In the vicinity of NAWCADLKE, water is generally supplied to the
populace by municipal supply wells. Some private wells exist, but
these are used primarily for irrigation and not as a source of
drinking water. In Lakehurst Borough there is a well field
consisting of seven 50-foot deep wells, located approximately two-
thirds, of a mile south of the eastern portion of NAWCADLKE. Three
of the seven wells (four of the wells are rarely operated) are
pumped at an average of 70 to 90 gallons per minute and supply
drinking water for a population of approximately 3,000. Jackson
Township operates one supply well in the Legler area, approximately
one-quarter mile north of NAWCADLKE, which supplies water to a very
small population (probably less than 1,000). in the immediate
vicinity of NAWCADLKE.
The history of the site dates back to 1916, when the Eddystone
Chemical Company leased from the Manchester Land Development
Company property to develop an experimental firing range for the
testing of chemical artillery shells. In 1919, the U.S. Army
assumed control of the site and named it .Camp Kendrick. Camp
Kendrick was turned over to the Navy and formally commissioned
Naval Air Station (NAS) Lakehurst, New Jersey on June 28, 1921.
The Naval Air Engineering Center (NAEC) was moved from the Naval
Base, Philadelphia to Lakehurst in December 1974. At that time,
NAEC became the host activity, thus, the new name NAEC. In January
1992, NAEC was renamed the Naval Air Warfare Center Aircraft
Division Lakehurst, due to a reorganization within the Department
of the Navy.
Currently, NAWCADLKE's mission is to conduct programs of technology
development, engineering, developmental evaluation and
verification, systems integration, limited manufacturing,
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procurement, integrated logistic support management, and fleet
engineering support for Aircraft-Platform Interface (API) systems.
This includes terminal guidance, recovery, handling, propulsion
support, avionics support, servicing and maintenance,
aircraft/weapons/ship compatibility, and takeoff. The Center
provides, operates, maintains product evaluation and verification
sites, aviation and other facilities, and support services
(including development of equipment and instrumentation) for API
systems and other Department of Defense programs. The Center also
provides facilities and support services for tenant activities and
units as designated by appropriate authority.
NAWCADLKE and its tenant activities now occupy more than 300
buildings, built between 1919 and 1989, totaling over 2,845,000
square feet. The command also operates and maintains: two 5,000-
foot long runways, a 12,000-foot long catapult and arrest runway,
one-mile long jet car test track, four one and one-quarter mile
long jet car test tracks, a parachute jump circle, a 79-acre golf
course, and a 3,500-acre conservation area.
In the past, various operations and activities at the. Center
required the use, handling, storage and occasionally the on-site
disposal of hazardous substances. During the operational period of
the facility, there have been documented, reported or suspected
releases of these substances into the environment.
INITIAL INVESTIGATIONS
As part of the DOD Installation Restoration Program and the Navy
Assessment and Control of Installation Pollutants (NACIP) program,
an initial Assessment Study was conducted in 1983 to identify and
assess sites posing a potential threat to human health or the
environment due to contamination from past hazardous materials
operations.
Based on information from historical records, aerial photographs,
field inspections, and personnel interviews, the study identified
a total of 44 potentially contaminated sites. An additional site,
Bomarc, was also investigated by NAWCADLKE. The Bomarc Site is the
responsibility of the U.S. Air Force and is located on Fort Dix
adjacent to the western portion of NAWCADLKE. A remedial
Investigation (RI) was recommended to confirm or deny the existence
of the suspected contamination and to quantify the extent of any
problems which may exist. Following further review of available
data by Navy personnel, it was decided that 42 of the 44 sites
should be included in the RI. Two potentially contaminated sites,
an ordnance site (Site 41) and an Advanced Underground Storage
Facility (Site 43), were deleted from the RI because they had
already been addressed. In 1987, NAWCADLKE was designated as a
National Priorities List (NPL) or Superfund site under the_federal
Comprehensive Environmental Response, Compensation and Liability
Act (CERCLA).
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ENVIRONMENTAL INVESTIGATIONS
Phase I of the Remedial Investigation (Rl-Phase I) was conducted
from 1985 to 1987 to (a) confirm or refute the existence of
contamination at potentially contaminated sites identified during
the previous studies; and (b) develop recommendations for further
Phase II investigations. The results of the Rl-Phase I were
presented in a report issued in 1987.
Phase II of the RI was initiated in the summer of 1988 to: (a)
confirm the results of the Phase I study, specifically the presence
or absence of contamination; (b) identify where contamination is
located; (c) assess the potential for contaminant migration; (d)
define the sources of contamination; and (e) support a feasibility
study and final actions at the sites. Based on the results of the
Phase II Investigation, several remedial actions were initiated.
Phase III of the RI was initiated in the summer of 1991 to: (a)
confirm the presence or absence of contamination at sites where the
results of previous investigations were not definitive; (b)
delineate the lateral and vertical extent of contamination; (c)
collect and evaluate data to perform a risk assessment and assess
the need for remedial action at sites.
These investigations indicated that the levels of chlorinated
solvents in the groundwater at and downgradient of Site 31 are not
consistently revealed through numerous sampling rounds and that
contaminants do not pose a risk to human health and the
environment.
STATUTORY DETERMINATIONS
The NJDEPE soil cleanup criteria (SCC) are To Be Considered (TBC)
criteria for determining the need for site cleanup. Although the
NJDEPE SCC are not promulgated requirements, these criteria are
considered an appropriate means by which to assess the risk to
human health and the environment posed by contaminants found in
soil. Therefore, NAWCADLKE has been determining the need for site
cleanup based upon NJDEPE SCC as well as EPA. risk-based levels and
other factors, such as aiding the effectiveness and duration of
existing groundwater remediation systems.
The cleanup criteria provide health based levels for residential
use, non-residential use and impact to groundwater (subsurface)
land uses and/or impacts. NAWCADLKE has assumed a non-residential
land use due to its mission and facilities is support of Naval
aviation. Due to our location in the Pinelands National Preserve
(Class I-PL (Pinelands)) and the shallow groundwater table, the
most stringent of the surface and subsurface (impact to
groundwater) non-residential cleanup criteria have been utilized in
our site comparisons.
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To satisfy the requirement for establishing EPA risk-based clean-up
criteria, an Endangerment Assessment was ;perf ormed in October 1992
which included calculated Preliminary Remedial Goals or PRGs. The
PRGs are chemical specific criteria which were developed using fate
and transport and the exposure equations associated with the
relevant pathways. The PRGs determined by calculation the
contaminant concentrations in affected media that would result in
acceptable exposure levels. PRGs were developed for each site
based upon one or more (current or potential) land-use scenarios.
Typically the NJDEPE SCC are more stringent than the calculated
PRGs. With this in mind, the SCC are also considered preliminary
clean-up goals at those sites which are determined to require
active remediation.
Section 121(d) of the Comprehensive Emergency Response,
Compensation, and Liability Act (CERCLA), as amended by the
Superfund Amendments and Reauthorization Act (SARA), requires that
any remedial action comply with any standard, requirement,
criterion or limitation of Federal or more stringent State
environmental statutes. These standards, referred to as
"applicable or relevant and appropriate requirements" (ARARs),
include the statutory requirements of the National Primary and
Secondary Drinking Water Regulations; the Toxic Substances Control
Act; the Clean Air Act; the Clean Water Act (CWA) (40 CFR 404)
which prohibits actions that impact a wetland; NJ Pollutant
Discharge Elimination System (NJAC 7:14A-1 et.seq.) which
determines permit requirements for alternatives involving
treatments which discharge effluent to groundwater or surface
water; the NJ Water Pollution Control Act (NJAC 58:10A-1 et.seq.)
which provide regulations regarding ground and surface water
discharge; and the Solid Waste Disposal Act (SWDA), among others.
ARARs are developed, refined and revised to take into consideration
new chemical data, site conditions, and potential remedial actions.
Promulgated standards and criteria were reviewed for application to
remedial actions for groundwater cleanup. To assess the need for
remediation, a set of chemical specific ARARs were developed for
comparison with the analytical results from groundwater. The
primary purpose of these criteria is to assess the degree of
contamination on the basis of adverse impacts on human health or
the environment. Therefore, regulatory health-based criteria are
used whenever possible. The rationale for selection of criteria is
dependent on the availability of regulatory standards for each
analyte, the stringency of the standard, the applicability of an
assumed exposure scenario, and the media contaminated.
EPA considers drinking water Maximum Contaminant Levels (MCLs),
Maximum Contaminant Level Goals (MCLGs), and State Practical
Quantitation Levels (PQLs) to be potential ARARs. The
determination of exactly which requirements are applicable or
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relevant and appropriate to a particular Super fund site should be
made on a site-specific basis.
Primary MCLs are Federally enforceable contaminant levels allowable
in public drinking water supplies. They have been established from
health-based data by EPA's Office of Drinking Water and are
described in the National Primary Drinking Water Regulations (40
CFR 141) established under the authority of the Safe Drinking Water
Act. MCLs are periodically revised as more information becomes
available. When MCLs are not available, proposed MCLs (PMCLs) are
used for the comparison criteria for some analytes.
On 13 January 1993, the Commissioner of the New Jersey Department
of Environmental Protection and Energy signed the revised N.J.A.C,
7:9-6 which include the Groundwater Quality Criteria. The Criteria
establish the groundwater classifications for the Pinelands,
including Class I-PL (Preservation Area) and Class I-PL (Protection
Area). The actual groundwater criteria are the natural quality and
background quality, respectively (N.J.A.C. 7:9-6.7). Under these
revised groundwater quality standards, NAWCADLKE groundwater is
classified as Class I-PL (Pinelands).
Practical Quantitation Levels (PQLs) are the lowest concentration
of a constituent that can be reliably achieved among laboratories
within specified (N.J.A.C. 7:9-6.9) limits of precision and
accuracy during routine laboratory operating conditions. PQLs are
considered to be ARARs.
PQLs are typically much more stringent than the Federal MCLs. In
order to comply with PQLs in some areas, a downgradient "line of
compliance" is established with the concurrence of the EPA, NJDEPE,
and local officials. This line of compliance is a monitored
boundary in which contaminants are not expected to cross. If
contaminant levels of concern are discovered at the line of
compliance, additional actions would be conducted which could
include additional monitoring and/or treatment. The establishment
of a active and passive remediation zone can help to minimize
potential adverse effects to the environment and minimize
.remediation costs while protecting human health.
Site 31 Description and Background
The former NAWCADLKE sanitary landfill (Site 31) is located to the
immediate southwest of the golf course and Callaway Road, south-
southeast of the magazine bunker and north of Rounds Road and the
former rifle range (see Figure 2) . Site 31 and the surrounding
downgradient area is referred to as Area D. The landfill became
operational in 1960 or 1961. In 1980, it was capped with
approximately 6" of topsoil. The New Jersey Department of
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Environmental Protection approved the closure of the landfill in
1980. The landfill is now a large grassy field surrounded with
trees and contains no landmarks. The area of the landfill is
estimated at 34 acres. The landfill received the trash and garbage
from the facility for a period of approximately 20 years.
A list of potentially hazardous materials that were reportedly
disposed of at the landfill is provided in Table I.
TABLE I - POTENTIALLY HAZARDOUS MATERIALS DISCARDED AT
INACTIVE SANITARY LANDFILL (SITE 31)
Estimated Estimated
Material Time Frame Quantity
Trash
Cutting oil
Solvents, paint, paint
thinner, paint cans
Hydraulic fluid
Asbestos
nU tSr dust control (over
1,000 yards)
Blacktop, concrete, wood,
nylon viebbing
Sand containing lead slugs
from rifle range
Bowzers full of waste
solvents and oils
Sludge from AVGAS tanks
Triple rinsed pesticide cans
Scrap metals
Freon Cylinders (50 Ib.Bt)
Transformer filters with PCBs
Elemental mercury (buried
after closure)
Fluorescent tubes in bags
Hydraulic fluid saturated
aircraft filters
1960-1980
1964-1976
1954-1976
1956-1976
1960-1976
1967-1968
1956-1976
1980
1960
1968-1969
1961-1976
Unknown
1972-1976
Unknown
1980
1956-1976
Unknown
Unknown
5,000 gallons
160 gal/yr
Unknown
5 tons
200 gallons
Unknown
200 cu.yds
Unknown
Unknown
Unknown
Unknown
400
Unknown
400 grams
1,000
tubes/year
250 per
month
It is estimated, however, that these potentially hazardous wastes
compose a very small percentage of total landfill waste, in
comparison to the volume of normal household wastes. A compilation
and analysis of landfill records on file at the NJDEPE show only
two instances of hazardous materials having been placed in the
landfill. One entry is hazardous waste containers (which does not
denote if empty or full) and one entry of dry hazardous waste.
10
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:-i^RO='JNC-i SAMPLING
LOCATION
bilt. No.jl, AREA u
SANITARY LANORUL (INACTIVE)
••*
'TO*CT R£M£DIAU INVESTIGATION - PHASt III
NAVAL AIR WARFARE CcNTES-AIRCSAFT DIVISION
LAKEHURS7. NCW JERSEY
Dames & Moore
NOTcDl0- " A.P.D.
7930-025
FIGURE 2. Area Map of Site 31
11
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These wastes are not described any further. The percentage of
hazardous waste disposed of between 1973-1976, according to these
records, is calculated as less than 0.005 percent.
Summary of Remedial Investigations
Between 1981 and 1984, seven monitoring wells (AK, AL, AM, AP, AQ,
AR and AY) were installed around the perimeter of the former
landfill, under the direction of NAWCADLKE. Groundwater samples
were collected from these wells in 1982, 1983, and 1984. In 1982,
the samples were analyzed for organic, inorganic", and physical
parameters considered by the EPA to be broadly representative of
landfill leachate. In 1983 and 1984, the samples were also
analyzed for the EPA priority pollutant volatile organic compounds.
The 1984 analysis also included pesticides, herbicides and PCBs.
No significant contamination was detected in these analyses. One
priority pollutant volatile organic compound, 1,1-Dichloroethane,
was detected in upgradient well AK in 1984 at a concentration of
5.2 ug/1.
In Phase I, November 1985 to January 1986, analyses of groundwater
samples from three supply wells .(SW-4, SW-8, SW-11) and two
monitoring wells installed downgradient from the site (DU and DV)
confirmed the presence of VOCs in groundwater.
In Phase II (August 1988 to December 1988), analysis of groundwater
samples from nine monitoring wells and three water supply wells at,
and downgradient of, the site confirmed the presence of VOCs in
groundwater and also revealed low levels of SVOCs (primarily
chlorobenzene) in some wells and metals, detected sporadically at
levels exceeding ARARs. Except in one well, metals were not
detected in filtered samples. In well AQ, metals were present at
low levels (well below ARARs) in filtered samples. A high level of
nitrate was detected in one of the two samples collected from one
of the supply wells (SW-11). Gross alpha, gross beta, and/or
radium-226 were detected at levels exceeding ARARs in some
unfiltered groundwater samples. Much lower levels of these
parameters (below ARARs) were detected in filtered samples from the
same wells.
January 1989, a surface gamma radiation survey conducted across the
site did not detect any gamma radiation above area background
levels.
January 1990, an aquifer characterization study was initiated. A
piezometer (HH) was installed adjacent to monitoring well DU and a
short-term pumping test was performed on well DU to estimate the
hydrologic properties of the aquifer. Analyses of groundwater
samples collected during the pump test confirmed the presence of
VOCs in the well.
12
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In Phase II, July 1990, five monitoring wells (AL, AM, AQ, AR, and
AY) in which radiological parameters have been detected at levels
exceeding ARARs in unfiltered samples collected during the Phase II
investigation, were resampled for radiological analysis. Neither
radium-226 or uranium-238 were detected at levels exceeding ARARs
in either filtered or unfiltered samples collected from these
wells.
In Phase III, July 1991 to April 1992, monitoring wells HL, HM, HN,
HO, HP and HQ, were installed to replace existing wells AK, AL, AM,
AP, AQ, and AR, respectively, due to the fact that the screen
intervals in the existing wells were entirely below the water
table. Four shallow and deep well pairs were installed
downgradient of the site, near the northern NAWCADLKE property
boundary. Groundwater samples were collected from: 1) all
monitoring wells in Area D; 2) two water supply wells and one
backup potable well downgradient from Site 31; and 3) three to four
different depth intervals at eight Hydropunch™ sampling locations.
The analysis of these samples revealed an area of potential
volatile organic contamination in groundwater extending from the
location of the former landfill downgradient (northeastward) to the
facility boundary and Ridgeway branch (see Figures 3 and 4).
The primary (most commonly detected) contaminants in groundwater at
Site 31 are chlorinated solvents (see Table II) . Three of these
chlorinated compounds (chlorobenzene, 1,2,4 trichlorobenzene and
vinyl chloride) are present at levels exceeding ARARs. Benzene is
also present, in a very limited area, at concentrations slightly
exceeding ARARs. Chromium, lead and mercury are present in
groundwater at levels exceeding ARARs in the vicinity of the former
base landfill. However, the presence of these metals is very
inconsistent and appears to be attributable to sediment in the
samples collected and not to metals dissolved in groundwater. This
is based on the turbid nature of groundwater samples taken from the
monitoring wells and the locally high background levels of metals
typically in such sediments. Results of filtered samples taken
from monitoring wells typically show metals to be undetectable or
at least an order of magnitude less than the unfiltered samples.
There is one potable water well (PW-37) and several supply wells to
the North and Northeast of Site 31 (see Figure 2). PW-37 has been
tested during the Phase III investigation and shows no VOCs. Since
this well is not downgradient of the area of contamination and
because of the low concentration of contaminants that have been
detected, it is highly unlikely that this potable water well will
be impacted by VOC contamination.
A landfill study was conducted at NAWCADLKE between 1982 and 1984
to collect data on leachate parameters. This data was also
13
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TABLE II - SITE 31 RESULTS
Maximum
ANALYTE ?S$5fted
Chloroform 0.38
1,2-Dichloroethane 0.54
1,1-Dichloroethane 4.63
1,2-Oichloroethene 24.00
Cis-1,2 Dichloroethene 9.14
Benzene 1.7
Toluene 0.64
Ethylbenzene 3.09
SUMMARY,
EPA
MCL
100
70
NL
100
70
5
1000
700
P,m-xylene 0.73 10,000
Chlorobenzene 11
1,3 Di chlorobenzene 11
1,2 Di chlorobenzene 5
1, 4 -Oi chlorobenzene 4.66
Benzyl alcohol 22
1,2,4 Trichlorobenzene 12
2 Methylnaphthalene 10
Naphthalene 4
4 Chloro 3 Methyl phenol 2
Trans 1,2 dichloroethene 5.62
Lead (filtered) 3.0
Radium- 226 (filtered) 1.9
vinyl chloride 49
NL
600
600
75
NL
9
NL
NL
NL
100
15
NL
2
GROUNDUATER
PQL Frequency .
of Detection
1
2
2 13%
2
2
1 4.7%
5
5
2
2 6.9%
5
5
5 19.0%
NL
1 2.7%
NL
NL
20
2
10
NL
5 4.3%
HI • Not listed or available
compared to the Phase II (1988) leachate data in order to
demonstrate trends in the parameters. The leachate data for Site
31 is shown in Table III.
Indicator
Parameters
Chloride
Nitrate
Sulfate
Fluoride
Table
(mq/l)
range
mean
range
mean
range
mean
range
mean
III- Landfill
1982
(9lf)
°1i~.Ia!
(2l!a)
(8:1)
Leachate
1983
6-10
(8.1)
°-1(i?l!
cil?6>
(8:1)
Parameters
1984
(8?1)4
°-(o\76)
(541.i)
(8:1)
1988
NQ-7.8
(2.86)
ND-1530
(73)
»°&
m
As can be seen from the data presented above, average
concentrations of landfill indicator parameters did not change
significantly during monitoring over the period 1982 to 1988. The
exception to this was nitrate levels detected in 1988 (Phase II).
The increase in nitrate concentration, however, was attributable
entirely to one sample collected from supply well SW-4, in which
14
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nitrate was present at 1530 mg/1. Nitrate was not detected in the
other sample collected from this well during Phase II.
The generally low levels detected, and lack of variation in
concentration with time, support the assumption that the majority
of biological degradation of organic waste in the landfill occurred
prior to the time monitoring began. It appears that the main
contaminants of concern leaching from the landfill are volatile
organic compounds including chlorinated aliphatics, chlorobenzenes,
and benzene. In summary, the monitoring of landfill indicator
parameters since 1982 at Site 31 has not revealed any significant
upward or downward trend and levels are generally low. It appears,
however, that the landfill is a source of low levels of volatile
organic contamination, probably resulting from waste solvents,
paint thinner, hydraulic fluid and other unidentified chemical
wastes which reportedly were deposited in the landfill.
During the initial scoping of the remedial investigation, it was
determined that potential impact to groundwater was of greater
concern than soil contamination and that groundwater sampling would
better reveal any potential contamination. Other factors that
contributed to the decision not to sample the soil in the landfill
include:
(1) The status of the landfill as a sanitary landfill; this
denotes that it was designed to receive typical household wastes,
not hazardous wastes.
(2) Size of the landfill; it was not anticipated that sampling
would result in the identification of potential source areas of
contamination due to the depth and large areal extent of the
landfill.
(3) The existence of a sufficient soil cover and grass over the
area. No visible signs of stressed vegetation or surficial soil
contamination are present.
(4) The concern raised from the lead reportedly deposited in the
form of sand from the rifle range was dismissed since it is
believed to be in the form of slugs or cartridges which could not
become airborne or pose other risks.
ENDANGERMENT ASSESSMENT
An Endangerment Assessment (EA) was conducted for NAWCADLKE to
assess the potential current and future human health risks and
potential environmental impacts posed by contaminated groundwater
detected during past and on-going site investigations.
For Site 31, four different scenarios representing current and
potential future land uses were evaluated to assess applicability
15
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to the site. Evaluated scenarios included military, light
industrial, construction, and residential land uses. For each of
these scenarios, human exposure is affected by mechanisms that
include direct contact, inhalation and ingestion.
More complete EA information for Site 31 can be found in Volume VI
of the Phase III RI, which is available as part of the NAWCADLKE
Administrative Record.
For Site 31, the summary will discuss (1) the chemicals identified
by the EA as contaminants of concern (COCs) , (2) the land use
assumptions upon which estimates of potential human exposure to
site contaminants are based, (3) the quantitative estimates of
'carcinogenic risk and noncarcinogenic hazard, (4) a summary of the
ecological concerns at the site and (5) a summary interpretation of
the EA findings with regard to need for site remediation.
CONTAMINANTS OF CONCERN
The contaminants identified at the site that were addressed by the
endangerment assessment included: l;4 Dichlorobenzene which was
detected in 19% of all samples, 1,1 Dichloroethane which was
detected in 13% of all samples, and Chlorobenzene at 6.9%; with no
levels detected above MCLs. Although other contaminants
(chlorinated compounds and benzene) were found at Site 31, they
were only detected in less than 5% of all the samples (tested for
that parameter). Compounds such as benzene, 1,2,4
trichlorobenzene, and vinyl chloride have been detected once or
twice out of 70 to 83 samples (less than 3% of samples) above NJ
groundwater standards or EPA acceptable limits. The lack of
consistent or frequent detection is the basis for screening out
these contaminants since risk scenarios assume daily or consistent
exposure to a contaminant.
LAND USE AND EXPOSURE ASSESSMENT
For Site 31, light industrial and residential exposures to
groundwater was assumed to be potential future exposure pathways.
Future residential exposure is based on the proximity of the site
and associated contaminant detection range to base housing areas
and the occurrence of existing nearby shallow non-potable water
supply wells.
HUMAN HEALTH RISK AND HAZARD FINDINGS
The results of the baseline endangerment assessment for groundwater
at Site 31 indicate that the hazard index resulting from chemicals
exhibiting noncarcinogenic hazard potential is 0.0057 under a
potential light industrial scenario and 0.1883 under a potential
future residential scenario. Both these hazard indices are below
the EPA limit of 1.0.
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Carcinogenic risks from groundwater may result from 1,4
Dichlorobenzene. The risk under a potential light industrial
scenario is 1.24 x 10"6 and under a potential future residential
scenario is 4.16 x 10"6-
The results of the endangerment assessment for groundwater at Site
31 indicate that potential carcinogenic risks resulting from
carcinogenic chemicals do not exceed the EPA's risk level point of
departure value of 10"6.
ECOLOGICAL ASSESSMENT FINDINGS
Site 31 is located between a runway and base housing areas. A
drainage basin associated with Site 31 surrounds the eastern
portion of the Ridgeway stream branch. Wetlands surround the
entire length of the stream. The surface drainage pattern is from
the south to the northeast toward Ridgeway Branch. The grasshopper
sparrow has been sighted in this area. The grasshopper sparrow is
a State-listed threatened species that is considered secure
globally, but rare in the State. It is limited to cultivated and
fallow fields, and open grasslands.
Rainbow pond, located downgradient of Site 31 adjacent to the
northeast corner of the golf course, was constructed by the U.S
Department of Agriculture Soil Conservation'Service in the 1950's.
This pond is used primarily for fishing and is posted with a sign
indicating it is to be used by youths up to 16 years in age.
Sampling of the surface water and sediment in Rainbow pond and the
Ridgeway Branch downgradient from the landfill indicate no VOC
contamination. Therefore, no adverse ecological effects on aquatic
species are determined to be present resulting from landfill
wastes.
SUMMARY
Potential present and future risks resulting from groundwater do
not exceed the EPA's acceptable risk level of 10"6. The need for
treatment and/or monitoring of groundwater should be further
evaluated. Groundwater contaminants at Site 31 are not at levels
that would pose an unacceptable risk to human health. In addition,
no adverse ecological effects due to contamination at the site were
found.
HIGHLIGHTS OF COMMUNITY PARTICIPATION
The Proposed Plan for Site 31 was issued to interested parties on
June 4, 1993. On June 16 and 17, 1993 a newspaper notification
inviting public comment on the Proposed Plan appeared in The Asbury
Park Press and The Ocean County Observer. On June 18, 1993, a
notification also appeared in The Air Scoop, the Center's weekly
17
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publication. The comment period was held from June 21, 1993 to
July 21, 1993. The newspaper notification also identified the
Ocean County Library as the location of the Information Repository.
A Public Meeting was held on June 30, 1993 at the Manchester Branch
of the Ocean County Library at 7:00 p.m. At this meeting,
representatives from the Navy, USEPA, and NJDEPE were available to
answer questions about the site, and the "No Action with
Groundwater Monitoring" determination. A list of attendees is
attached to this Record of Decision as Appendix A. Comments
received and responses provided during the public meeting are
included in the Responsiveness Summary, which is part of this
Record of Decision. No written comments were received during the
public comment period. A transcript of the meeting is available as
part of the Administrative Record.
The decision document presents the selected action (ie. No Action
with Groundwater Monitoring) for Site 31 at NAWCADLKE in Ocean
County, New Jersey, chosen in accordance with CERCLA, as amended by
SARA and, to the extent practicable, the National Contingency Plan
(NCP) . The decision for the site is based on the information
contained in the Administrative Record, which is available for
public review at the Ocean County Library, 101 Washington Street,
Toms River, New Jersey.
SCOPE AND ROLE OF RESPONSE ACTION
The results of the environmental investigations conducted show no
verifiable evidence of significant contamination at Site 31. The
levels of chlorinated solvents have been determined to not pose a
risk to human health or the environment. However, a five year
monitoring plan will be implemented to ensure continued compliance
with groundwater standards and monitor the risk to human health and
the environment.
SUMMARY OF SITE CHARACTERISTICS
The location of Site 31 within NAWCADLKE is shown in Figure 2. The
general direction of groundwater flow at NAWCADLKE is to the east-
northeast. Summary of the chemicals detected in the analyses of
groundwater collected at the site is provided in Table II.
The results of the Remedial Investigations, including the
endangerment assessment, indicate that conditions at Site 31 pose
no unacceptable risk to human health and the environment.
DESCRIPTION OF ALTERNATIVES
Three remedial alternatives (and the "no action" alterative) were
developed for analysis in the FFS for Site 31. Each of these
18
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alternatives is described in detail below.
Alternative 2, Limited Action- Restricted use of Groundwater, has
been implemented to ensure protectiveness of human health.
ALTERNATIVE 1: NO ACTION
Estimated Construction Cost:
Estimated Net O&M Cost: $0
Estimated Implementation Time
Frame: N/A
$0
This alternative involves no additional actions at Site 31.
Alternative 2: LIMITED ACTION/ GROUNDWATER USE RESTRICTION
Estimated Construction Cost: $0
Estimated O&M Cost: $0
Estimated Implementation Time: 1 month
There are a number of backup potable wells and supply wells
affected by the groundwater contamination from Site 31 (See Table
IV) . Groundwater use restrictions would be implemented by
inactivating the identified wells until further study is completed.•
Wells affected by Site 31 are: SW-3, SW-8, SW-10, and SW-11. A
study is currently underway for supply wells 3, 8 and 10 to
determine if these wells should be refurbished, replaced or even
relocated. The study will determine the costs associated with
treating the water from these wells, replacing the wells with
higher capacity, deeper wells, or relocating the supply wells to
another location on base. Potentially affected wells near Site 31
will not be used. The buildings surrounding Site 31 are supplied
with potable water from the Center's Hill water system.
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Table IV - Supply Wells Downgradient of Site 31
SUPPLY WELL
SW-8
SU-10
SU-3
SU-11
CONTAMINANT
not sampled
not sampled
1,1 OCA
1.2 DCE
1,2 DCE
Lead
CONCENTRATION
ppb
9.0
3.0CJ)
2.0
Filt=3.0
JINKING
STANDARD
2.0
10
10
15
WELL DEPTH AND USAGE
51 feet, Old standby
well, not used.
51 feet, Golf course
irrigation.
54 feet
Standby well, not used
22 feet, not used.
Consumption of contaminated groundwater from Site 31 through off-
base drinking wells is unlikely. The closest private wells are
more than half a mile from the NAWCADLKE boundary. In addition,
the stretch of wetlands at the base boundary is expected to act as
a hydraulic barrier. In the unlikely case of off-base
contamination, restrictions on private wells have already been put
in place by Jackson Township officials. The residences which might
be affected (those on Route 571) were put on the Jackson Township
municipal water supply due to their proximity to the Legler
Landfill, which is also an NPL site.
ALTERNATIVE 3; GROUNDWATER MONITORING
Estimated Construction Cost: $ 11,000 for monitoring
wells and $3,500 for monitoring points
Estimated Net O&M Cost: $99,000/yr (semi-annual
sampling)
Five year cost: $509,500
Estimated Implementation Time Frame: 3 months
This alternative involves groundwater monitoring of the aquifer.
No contaminants would be treated or contained unless results of the
monitoring shows a sustained increase in .concentration of any
contaminants of concern to levels above ARARs or are at levels that
may pose an unacceptable risk to human health and the environment.
Under this alternative, no further action to control the source in
Site 31 would be taken. Monitoring of the site can be implemented
by using previously installed monitoring wells and adding
additional well points where required.
In .addition, the design of the monitoring system would include
shallow well points in the downgradient wetlands or across major
water bodies to act as a "line of compliance" for Area D. These
well points could be installed with minimal disruption of the
20
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wetlands.
Monitoring would consist of taking samples from all monitoring
wells at the site semi-annually for 5 years, followed by a
comprehensive evaluation of the data. The sampling program would
be re-evaluated based upon each set of results. All sampling and
analytical procedures would follow USEPA standards. Testing
parameters and additional well locations would be determined during
the remedial design. The monitoring system would be capable of
achieving results necessary for the evaluation of ARARs compliance.
The monitoring plan (ie. remedial design) will be submitted to the
EPA and NJDEPE for review and concurrence prior to initiation.
The sampling data generated by monitoring can be assimilated into
a groundwater model as part of our in-house Geographic Information
System (GIS) . This database system is an excellent tool that will
allow the Navy to effectively model rates of contaminant flow and
predict contaminant plume attenuation.
ALTERNATIVE 4: GROUNDWATER PUMPING, PRETREATMENT FOR INORGANICS,
AIR STRIPPING, CARBON TREATMENT AND AQUIFER RECHARGE
Estimated Construction Cost: $1,339,425
Estimated Net O&M Cost: $150,000/yr
Total cost: $2,839,425
Estimated Implementation Time Frame: 12 months
Time frame for operation of system: 10 years
This alternative involves groundwater pumping from recovery wells
to retrieve contaminants. To treat the. volatile organic
contaminants in the extracted groundwater, an initial flow
equalizer, a pretreatment unit for removal of metals and .solids,
air stripping columns (99% VOC removal), an activated carbon
adsorber for air stripper effluent and a granular activated carbon
polishing filter would be required.
The number of wells and pumping rate would .need to be determined
through groundwater modelling during the design phase of the
remedial action implementation.
The effluent exiting the air stripper will comply with the Clean
Air Act and federal and state discharge limits. The treated
groundwater, which will meet Federal and State drinking water
standards, will be recharged to the aquifer through irrigation/
infiltration piping or spraying upgradient of the site.
This alternative will halt the continued migration of the
contaminated plume and enhance groundwater quality.
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SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
The alternatives identified above were evaluated using criteria
derived from the National Contingency Plan (NCP) and SARA of 1986.
These criteria relate to the SARA amendment of Section 121 of
CERCLA (Section 121(b)(1)) and Section 300.430(e)(9) of the NCP and
are as follows:
During the detailed evaluation of remedial alternatives, each
alternative is assessed against the nine evaluation criteria which
are summarized below.
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 requirements
(ARARs), and/or provides the basis for a waiver.
3. Lona 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 Toxicitv, Mobility or Volume through Treatment
evaluates an alternatives ability to reduce risks through treatment
technology.
5. Short Term Effectiveness addresses the cleanup time frame and
any adverse impacts posed by the alternative during construction
and implementation phase until clean up goals are achieved.
6. Implementabilitv is an evaluation of the technical feasibility,
administrative feasibility and availability of services and
material required to implement the alternatives.
7. Cost includes an evaluation of capitol costs, annual operation
and maintenance (O&M) costs, and net present worth costs.
8. Acrencv Acceptance indicates whether the EPA and State concurs
with, opposes or has no comment on the preferred alternative in
terms of technical and administrative issues and concerns.
9. Community Acceptance will be addressed in the Record of
Decision (ROD) following review of public comments on the RI/FS
reports and the Proposed Plan.
22
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This section will compare all of the alternatives for Site 31 using
the nine criteria outlined above.
ALTERNATIVE I: NO ACTION
ALTERNATIVE 2: GROUNDWATER USE RESTRICTION
ALTERNATIVE 3: GROUNDWATER MONITORING
ALTERNATIVE 4: GROUNDWATER PUMPING, PRETREATMENT FOR INORGANICS,
AIR STRIPPING, CARBON TREATMENT AND AQUIFER
RECHARGE
Overall Protection of Human Health and the Environment.
Alternative 1, the no action alternative is currently protective of
human health and the environment since risks are within EPA
acceptable guidelines. However, long term protectiveness cannot be
ensured under the no action alternative if the levels of
contaminants leaching from the landfill increase. Alternative 2
would allow for the most immediate and effective protection of
human health. Alternative 4 would treat the groundwater, thereby
eliminating contaminants. However, alternative 3 will track
pollutant levels and movement, thereby allowing for a decision to
implement a remedial action if required.
Compliance with ARARs. At Site 31, the VOCs have been detected
very inconsistently over time.
Alternative 4 would retrieve and treat any existing VOC
contamination of the groundwater. However, alternative 4 may
contribute to significant drawdown in the downgradient wetlands
regions. This drawdown could lower surface water levels thereby
harming portions of the wetlands.
Alternative 3 includes a "line of compliance". At this line,
groundwater will be monitored to determine .whether ARARs are
achieved. If, .based on monitoring, contaminants are consistently
detected above ARARs, active remediation at the site would be
reconsidered.
Alternative 1 and 2 may comply with ARARs in the short term, but
because contaminants are left in place at the Site 31 sanitary
landfill, and because of the fluctuating, inconsistent, low level
contaminant concentrations over time and location, the long term
prospects of compliance can only be determined through monitoring,
as detailed in Alternative 3.
Long-Term Effectiveness and Permanence. Alternative 4 offers the
greatest long-term effectiveness and permanence since it will
recover and treat contamination. Alternative 2 will not treat
contamination. However, alternative 2 is protective of human
health through the elimination of receptor pathways via
institutional controls. Alternative 3 can monitor contaminant
concentrations and will provide information as to whether levels
are found consistently above ARARs in the future or if an
23
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unacceptable risk to human health and the environment is shown.
Reduction of Toxicity. Mobility or Volume. Alternative 4 offers
the greatest reduction of toxicity, mobility and volume of the
plume since it recovers and treats contaminated groundwater.
Alternatives 1, 2 and 3 will not reduce the mobility or volume of
the plume. However, alternative 2, which has already been
implemented, is protective of human health. Alternative 3 would
monitor contaminant movement and levels. If contaminants are shown
to pose a threat to human health and the environment under
alternative 3, the need for remedial action would be re-evaluated.
Short-Term Effectiveness. Alternative 4 offers the greatest short
term effectiveness in decreasing contaminant levels. However,
alternative 2 is more effective in the short term of reducing
potential risks to human health through restriction of groundwater
usage. Alternative 3 would be effective in the short term for
confirming or refuting the presence or level of contaminants which,-
to date, have been shown to be inconsistently present.
Implementabilitv. Alternative 2 offers the greatest
implement ability followed by Alternative 3. Alternative 4 requires
the construction of treatment facility capable of capturing,
treating and discharging groundwater. Implementability of
alternative 4 also requires computer modeling of recovery systems
to limit adverse effects on the downgradient wetlands.
Cost. The costs associated with alternative 2 are minimal. Costs
of monitoring, alternative 3, are significantly less than
alternative 4, where a groundwater treatment facility is
constructed and operated for a number of years. Costs shown below
are for implementing each alternative in Area D.
Alternative 1;
Alternative 2;
Alternative 3:
Alternative 4
COSTS
No Action $0
Limited action/ $0
groundwater use restrictions
Groundwater monitoring $509,500
Groundwater pumping, $2,839,425
pretreatment for inorganics, air stripping,
carbon treatment, and aquifer recharge
State Acceptance.
selected remedy.
The State of New Jersey concurs with the
Community Acceptance. All public questions were answered during
the public meeting. No additional written questions or comments
were received during the public comment period.
24
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THE SELECTED ALTERNATIVE
The preferred alternative for Site 31 is alternative 3, "no action
with groundwater monitoring". Alternative 3 is protective of human
health and the environment and will monitor the existence or
potential migration of low levels of contaminants in groundwater.
Alternative 2, restriction of groundwater usage, has already been
implemented and is an important factor in assuring protection of
human health.
Testing of groundwater will be conducted by a Certified Laboratory
Program (CLP) or equivalent laboratory in accordance with EPA
established methods and protocols. The data generated will be
incorporated into a computer groundwater model which is designed to
predict contaminant movement and demonstrate trends in contaminant
levels. Annual reports will be delivered to the EPA and State and
will become part of the NAWCADLKE Administrative Record. Although
current data does not indicate impacts on human health and the
environment from contaminants in groundwater, this issue will
continue to be evaluated over time.
It should be noted that this Record of Decision addresses only Site
31 and is not intended to represent the remedial action status for
the rest of the areas of concern at NAWCADLKE. Each site's unique
environmental conditions and concerns have .. .been or will be
addressed in separate proposed plans.
Under Section 121 of CERCLA and Section 300.430(f)(5) of the NCP,
selected remedies must meet certain statutory and regulatory
requirements. These requirements and a description of how the
selected remedy satisfies each requirement are presented below.
Protection of Human Health and the Environment
There is no unacceptable risk to human and health and the
environment posed by site. However, restriction of groundwater use
in the area has been implemented to prevent its use for drinking
purposes. The selected alternative will allow the groundwater to
be monitored for five years. If within that timeframe, results of
sampling indicate a threat to human health and/or the environment,
the site will be readdressed to consider active remediation.
Compliance with ARARs
Although sampling results have resulted in random occurrences of
level above ARARs, the overall groundwater picture reveals that
levels of chlorinated solvents are very low if at all present. The
selected alternative enables frequent sampling so that compliance
with ARARs can be determined over time.
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Cost-Effectiveness
The selected remedy is a cost-effective means to determine
compliance with ARARs and potential threat to human health and/or
the environment over time. Since a comprehensive network of
monitoring wells already exists in the area, capital costs
associated with the selected alternative is low.
Document of Significant Changes
The Proposed Plan for Site 31 was released for public comment on
June 21, 1993. The Proposed Plan identified "No Action with
Groundwater Monitoring" as the preferred alternative. No written
comments were received during the 30 day comment period. All
verbal comments were responded to at the public meeting on June 30,
1993. Upon review of the comments, it was determined that no
changes to the selected alternative, as it was originally
identified in the proposed plan, were necessary.
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