United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R02-89/078
June 1989
SEP A
Superfund
Record of Decision
Bog Creek Farm, NJ
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50272-101
REPORT DOCUMENTATION i. REPORT NO. 2.
PAGE EPA/ROD/R02-89/078
4. Title and Subtitle
SUPERFUND RECORD OF DECISION
Bog Creek Farm, NJ
Second Remedial Action - Final
7. Author(»)
8. Performing Organization Name and Addresa
12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
3. Recipient's Accession No.
5. Report Date
06/28/89
6.
8. Performing Organization Rept
No.
10. ProjecVTssk/Work Unit No.
11. Contract(C) or Grant(G) No.
(C)
(G)
13. Type of Report & Period Covered
800/000
14.
15. Supplementary Notes
16. Abstract (Limit: 200 words)
The Bog Creek Farm site is a 4-acre disposal area consisting of a man-made pond, bog,
and trench in Howell Township, Monmouth County, New Jersey. The site is bordered to
the north by Squankum Brook, to the west by two residences and a riding stable, and to
the south and north by open fields. Between 1973 and 1974 organic solvents and paint
residues were dumped around a trench in the eastern portion of the property, creating a
highly contaminated soil area. Some chemicals migrated into a shallow underlying
aquifer, creating a contaminant plume that discharged to the pond and bog along the
northern border of the site and to the north branch of Squankum Brook. In late 1974
the property owner removed some waste from the disposal trench and covered the trench
under direction from the Howell Township Health Department. A 1985 Record of Decision
selected a first operable unit remedy that involved excavating the soil from the waste
trench, pond, and bog areas and incinerating the soil onsite. This second operable
unit focuses on remediating the contaminated ground water in the shallow aquifer and
the contaminated brook sediment. The primary contaminants of concern affecting the
sediment and ground water are VOCs including benzene, toluene and xylenes; and other
organics including phenols.
(See Attached Sheet)
NJ
17. Document Analysis a. Descriptors
Record of Decision - Bog Creek Farm,
Second Remedial Action - Final
Contaminated Media: sediment, gw
Key Contaminants: VOCs (benzene, toluene, xylenes), other organics
b. Identifiers/Open-Ended Terms
(phenols)
c. COSATI Field/Group
18. AvailabiSty Statement
19. Security Class (This Report)
None
20. Security Class (This Page)
None
21. No. of Pages
42
22. Price
ANSI-Z39.13)
See Instructions on Reverse
OPTIONAL FORM 272 (4-77)
(Formerly NT1S-JS)
Department of Commerce
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EPA/ROD/R02-89/078
Bog Creek Farm, NJ
Second Remedial Action - Final
16. Abstract (Continued)
The selected remedy for this site includes ground water pumping and treatment using air
stripping, hydrogen peroxide/ultra violet photolysis oxidation, carbon adsorption, and
reinjection; excavation of brook sediment, followed by onsite incineration and onsite
disposal; and stream bed restoration using clean sand or soil of similar consistency to
the existing material. The estimated present worth cost for this remedial action is
$6,927,000, which includes annual O&M costs of $663,000 for ten years of ground water
treatment.
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DECLARATION STATEMENT
RECORD OF DECISION
Bog Creek Farm
Site Name and Location
Bog Creek Farm, Howell Township, Monmouth County, New Jersey
Statement of Basis and Purpose
This decision document presents the selected remedial action
for the Bog Creek Farm site, in Howell Township, New Jersey,
developed in accordance with the Comprehensive Environmental
Response, Compensation, and Liability Act, as amended by the
Superfund Amendments and Reauthorization Act, and, to the extent
applicable, the National Contingency Plan. This decision is
based on the administrative record for the site. The attached
index identifies the items that comprise the administrative
record upon which the selection of the remedial action is based.
The State of New Jersey has concurred with the selected remedy.
Assessment of the Site
Actual or threatened releases of hazardous substances from this
site, if not addressed by implementing the response action
selected in this Record of Decision, may present an imminent and
substantial endangerment to public health, welfare, or the
environment.
Description of the Selected Remedy
The remedial alternative presented in this document is a perma-
nent solution for the contaminated groundwater plume at the site
and the contaminated sediment in the north branch of Squankum
Brook. This action is the second operable unit at the Bog Creek
Farm site. The source of contamination was addressed in the
first Record of Decision for the site, which was signed on
September 30, 19S5.
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This, second operable unit, action consists of the following
components:
• Groundwater extraction, treatment, and reinjection to restore
the Upper Kirkwood aquifer to cleanup goals identified in the
Decision Summary.
• Excavation and incineration of contaminated sediment from the
north branch of Squankum Brook.
Declaration
The selected remedy is protective of human health and the
environment, attains Federal and State requirements that are
applicable or relevant and appropriate for this remedial action,
and is cost-effective. This remedy satisfies the statutory pre-
ference for remedies that employ treatment as a principal element
to reduce the toxicity, mobility, or volume of contaminated media
and utilizes permanent solutions and alternative technologies to
the maximum extent practicable.
Acting Regional Administrator
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Decision Summary
Bog Creek Farm
Supplemental Remedial Action
SITE LOCATION AND DESCRIPTION
The Bog Creek Farm site is located on Monmouth County Road 547 in
Howell Township, Monmouth County, New Jersey. The north branch
of SquanJcum Brook forms the northern border of the site (Figure
1). Two residences and a riding stable are located to the west
of the contaminated area and open fields are situated to the east
and south. Organic solvents and paint residues, as well as
trash, were apparently dumped in and around a trench located in
the eastern portion of the property, designated Block 46 Lot 29
on the Howell Township tax map.
The water table aquifer at the site is located in the Kirkwood
geologic formation. Deeper aquifers are protected by layers of
relatively impermeable material and an upward hydraulic gradient
(water moves from the deeper aquifer, the Lower Kirkwood, to the
shallow aquifer, the Upper Kirkwood). Residences in the vicinity
of the site have private wells but are not threatened by site
contamination.' Surface water runoff and groundwater in the
shallow aquifer discharge to the north branch of Squankum Brook.
Squankum Brook enters the Manasquan River approximately one mile
downstream from the site. A reservoir for public water supply is
being built that will draw water from the Manasquan approximately
three miles downstream from the site.
SITE HISTORY AND ENFORCEMENT ACTIVITIES
Dumping at the site is believed to have occurred in 1973 and
1974. Chemical waste dispersed through the sandy soil underlying
the site creating an area of highly contaminated soil. Some
chemicals also migrated in the groundwater of the shallow aqui-
fer, creating a contaminant plume, and discharged to a pond and
bog along the northern border of the site and to the north branch
of Squankum Brook.
Late in 1974, the property owner removed some waste from the
disposal trenches and covered the trenches under direction from
the Howell Township Health Department. Over the next several
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NORTH BRANCH OF SQUANKUM BROOK
FIGURE 1
BOG CREEK FARM
HOWELL TOWNSHIP
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-3-
years, the Howe11 Township Health Department and the New Jersey
Department of Environmental Protection (NJDEP) monitored the
site. Bog Creek Farm was proposed for addition to the National
Priorities List (NPL) of Superfund sites in December 1982. After
a public comment period, the status of the site on the NPL was
changed to final in September 1983.
The EPA began a remedial investigation and feasibility study
(RI/FS) in 1984 to determine the nature and extent of contamina-
tion at Bog Creek Farm. This study determined that the greatest
hazards at the site were the soil near the waste trench, which
was highly contaminated primarily with volatile organic com-
pounds, and the pond and the bog where migrating compounds tended
to accumulate at the surface.
f
A Record of Decision (ROD) was signed on September 30, 1985 that
selected a first operable unit remedy for these most hazardous
areas. The first operable unit remedial action involves exca-
vating soil from the waste trench, pond, and bog areas (see
Figure 2) and incinerating it to destroy the organic contami-
nants. A remedial design was performed to develop and advertise
specifications for this action and, in January 1989, a contractor
was selected to implement this remedy.
The first operable unit ROD also specified that the EPA would
perform an additional study to determine the most appropriate
method to address the residual contamination. The investigation
was focused on the soil and groundwater in the shallow aquifer.
The results of that study are presented in the supplemental RI/FS
reports and summarized in this (second operable unit) ROD.
In October 1983, the EPA sent information-request letters, pur-
suant to Section 3007 of the Resource Conservation and Recovery
Act to Fred Barry (the former owner of the property and generator
and transporter of waste to the site), A.I.C.O. of Old Bridge,
New Jersey (the current owner of the property), and Sam Khoudary
(a representative of A.I.C.O.). A notice letter was sent to Fred
Barry in September 1985 offering him the opportunity to conduct
the remedial design and implementation of the first operable unit
remedial action. The EPA received no response to this letter.
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^ NORTH BRANCH OF
'SS-1
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COMMUNITY RELATIONS HISTORY
Community relations activities began with the first operable unit
RI/FS in 1984. Public meetings were held to present the EPA's
plans and findings, and the first operable unit RI/FS reports and
the ROD were placed in public repositories. The public reposi-
tories are located at the Howell Township Municipal Building and
the Howell Township Municipal Library. A formal public comment
period was held in connection with the first operable unit ROD,
and the comments and responses were summarized in the Responsive-
ness Summary section of that ROD.
The reports for the second operable unit were placed in the
public repositories in 1989. These include the Remedial Inves-
tigation and toxicity study reports (February), the Feasibility
Study report (April), and the Proposed Plan (May). The Proposed
Plan summarizes the second operable unit RI/FS and identifies the
EPA's preferred remedial alternative for the second operable
unit. A formal public comment period opened on May 15, 1989,
with the release of the Proposed Plan, and closed on June 16,
1989.
A public meeting was held on May 22, 1989. All comments received
during the public comment period and at the public meeting are
addressed in the Responsiveness Summary of this ROD. A tran-
script of the public meeting is also available in the administra-
tive record for this site, which is available in the public
information repositories and at the EPA's Region II office.
SCOPE OF THE OPERABLE UNIT
The EPA is addressing the remediation of the Bog Creek Farm site
in two phases, or operable units. The first operable unit was
the subject of the 1985 ROD. It addressed those chemicals that
were dumped at the site that tend to adhere to soil particles and
resist moving in the groundwater (the source areas) and the pond
and bog, where chemicals accumulated at the surface. The sup-
plemental RI/FS addressed those chemicals that tend to migrate in
the groundwater, forming a contaminant plume.
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SUMMARY OF BITE CHARACTERISTICS
The groundwater, soil, surface water, and brook sediment were
sampled during the supplemental RI/FS for chemical analyses. In
addition, toxicity tests were performed on samples from the north
branch of Squankum Brook. Detailed results of this sampling are
contained in the supplemental Remedial Investigation report and
the toxicity study report. The data are summarized in the fol-
lowing sections.
Groundvater
The unconfined aquifer at the site is the Upper Kirkwood. The
depth to the base of the Upper Kirkwood varies from approximately
10 to 30 feet below the surface across the site. The depth to
the water table ranges from the surface (at the north branch of
Squankum Brook) to approximately 10 feet below the surface.
The groundwater flows to the north and northeast, discharging to
the north branch of Squankum Brook. The brook forms a ground-
water barrier, preventing the flow of contaminants further north.
The material below the Upper Kirkwood is relatively impermeable
and forms a semi-confining layer at the top of the Lower Kirk-
wood. Water in the Lower Kirkwood is under pressure, so any
leakage between the two Kirkwood units is upward. As a result,
the contaminated plume at the site is limited to a small pocket
of the Upper Kirkwood aquifer. Migration downward, into the
Lower Kirkwood, and to the south and west is prevented by
hydraulic gradients, and migration to the north is limited by the
north branch of Squankum Brook.
Chemical analysis of groundwater samples from the Upper Kirkwood
aquifer detected a variety of organic contaminants. The most
prevalent compounds are toluene, xylene, 1,1,1-trichloroethane,
benzene, 4-methyl-2-pentanone (methyl isobutyl ketone), benzoic
acid, phenol, and 1,2-dichlorobenzene. The highest concentra-
tions were found just north of the waste trench excavation area
and are shown on Figure 3.
Soil
Soil borings were used to recover samples from four depths, as
much as 22 feet below the surface. The locations of the borings
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GROUNOWATEN CONTAMINATION
FIGURE 3
GROUNDWATER CONTAMINATION
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-8-
are shown on Figure 3. These samples were used to determine the
level of soil contamination in the area of concern for this
operable unit (outside of the area being excavated). The chemi-
cals found in the soil are listed in Table 1.
As with the groundwater contamination, the highest concentrations
in the soil were found just north of the waste-disposal trench.
Samples from 7 to 9 and 13 to 15 feet below the surface were the
most contaminated. Few compounds, at relatively low concentra-
tions, were found in samples from the top two feet and from the
20- to 22-foot depth.
Surface Water
Three samples of surface water were collected from the north
branch of Squankum Brook. Sampling locations are shown on
Figure 2. Chemical analysis revealed only low levels of organic
chemicals in the surface water. These contaminants are most
likely entering the brook through migration in the groundwater.
Sediment
Five sediment samples were collected from the north branch of
Squankum Brook as part of the supplemental RI. Sampling loca-
tions are shown on Figure 2. The highest concentrations of
organic contaninants were found at sampling locations SS-3 (just
upstream from the bog) and SS-4 (adjacent to the bog). Although
the data indicated low concentrations of contaminants, which did
not present a public health risk, the EPA resampled the brook to
perform toxicity studies to determine whether the contaminants
were adversely affecting non-human receptors.
The results of the toxicity study performed by the EPA's
Environmental Response Team.(ERT) are available in the public
repositories. Three samples were collected: S-l was upstream
from the waste disposal area but downstream from the stables, S-2
was adjacent to the bog, and S-3 vas downstream from the bog.
Unlike previous samples, these were collected in parts of the
brook where the water moves the slowest and, therefore, sediment
deposits are the greatest. Chemical analyses of these samples
found higher levels of contaminants than had been detected in
earlier samples.
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Table 1
Soil Contaminants
All Concentrations in parts per billion (*g/kg)
Conpound
Volatile...
Methylene chloride
Acetone
1,1-Dichloroethane
Chloroform
1.1,1-Trichloroethane
Trichloroethene
Tet rachIoroethene
Toluene
Total xytenes
trans-1,2-0ichloroethane
2-Butanone
Benzene
Ethylbenzene
1,2-Dichloroethane
4-Methyl-2-pentanone
2*Hexanone
Chtopomethane
Styrene
Carbon disulfide
Carbon tetrachloride
1,1,2-Trichloroethane
Seanvolatile...
4-Nethylphenol
Benzoic acid
Naphthalene
Methylnaphthalene
di-n-Butyl phthalate
bis(2-Ethylhexyl) phthalate
di-n-Octyl phthalate
Phenol
1,2-Oichlorobenzene
2-Methylphenol
Phenanthrene
Benzyl alcohol
Fluoranthen*
Pyrene
Isophorone
Anthracene
N-NitrosodiphenyI amine
1,4-0ichlorobenzene
Benzyl butyl phthalate
Oiethyl phthalate
Benzo(g,h,i)perylene
Hexach(orobutadiene
HexachIorobenzene
Concentration
Range
NO - 3300
NO • 21,000
NO • 2200
NO - 570
NO • 5900
NO - 26.000
NO - 1800
NO - 32,000
NO • 38.000
NO - 20
NO - 18,000
NO • 10,000
NO - 9700
NO • UOO
NO • 23,000
NO - 77
NO
NO • 7100
NO
NO
NO
NO - 723
NO • 1072
NO • 6100
NO • 1200
NO - 22,170
HO • 5900
NO • 290
NO • 4000
NO • 3200
NO • 300
NO - 150
NO - 1300
NO - 770
NO • 110
NO - 290
NO - 120
NO - 2300
HO - 170
HO • 580
HO - 210
NO • 134
HO - 268
NO
Location of Highest
Concentration
•3 (7-9')
•2 (13-15')
•31 (13-15')
-31 (13-15')
•31 (13-15')
-31 (13-15')
-3 (7-9')
-1 (7-9*)
•1 (7-9')
•21 (13-15')
-2 (13-15')
31 (13-15')
1 (7-9')
31 (13-15')
-2 (13-15-)
B-11 (7-9»>
B-1 (7-9')
B-11 (0-2')
B-H (7-9')
B-25 (7-9')
B-25 (7-9')
B-11 (0-2')
B-15 (0-2«)
-3 (20-22')
-25 (7-9')
-18 (7-9')
•25 (0-2')
-29 (7-9')
-18 (7-9-)
B-25 (0-21)
B-25 (13-15')
B-5 (13-15')
B-24 (13-15')
B-1 (7-9')
B-1 (7-91)
B-1 (7-9')
B-3 (7-91)
B-11 (13-15')
B-U (7-9-)
Hean
376
2969
30
11
100
388
66
1244
1594
NO
534
212
196
20
784
2
191
10
26
110
27
970
730
4
116
79
9
2
33
13
1
10
1
101
2
34
-8
3
3
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The toxicity of the samples was measured by exposing two types of
test organisms to the contaminants, paphnia macma (water flea)
and Pimephales promelas (fathead minnow) were the two test
organisms used. The fathead minnow showed no significant effect
during the bioassay. However, the Daphnia showed higher toxicity
for the sample from station S-2 as compared to the upstream and
downstream samples.
SUMMARY OF REMEDIAL OBJECTIVES
The EPA, in consultation with the NJDEP, developed remedial
action objectives for the second operable unit. The remedial
objectives are based on the results of the public health risk
assessment, the environmental impacts reflected in the chemical
data and the toxicity study, and a consideration of the appli-
cable or relevant and appropriate requirements of other Federal
and State environmental and public health laws. The remedial
objectives were used to guide the development and evaluation of
remedial alternatives in the supplemental FS. This section of
the ROD summarizes the development of the remedial objectives.
The soil and groundwater that make up the shallow aquifer at the
site were considered as a unit. Public health risks from this
unit are limited because the contaminated material remaining
after the implementation of the first operable unit will be below
the surface and the migration of contaminants in the aquifer is
limited by the groundwater flow pattern to a small pocket of
contamination. The only exposure scenario evaluated in the risk
assessment that indicated significant health threats involved the
construction of a house with a ten-foot deep basement in the con-
taminated area. This scenario assumed that all of the volatile
contaminants had the carcinogenic potency of benzene and that a
significant amount of these volatile organic compounds would leak
into the basement. Based on the limited public health threat and
the rate at which contaminants appear to be leaving the soil
(comparing the 1987 and 1984 data), the EPA and the NJDEP decided
it was not necessary to perform a remedial action for the soil.
The groundwater is highly contaminated; however, there is no
human exposure to contaminants since there are no wells within
the plume and, as described previously, the plume is hydrauli-
cally contained. The contaminated groundwater is, however,
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discharging to the north branch of Sguankun Brook, where it is
partly responsible for the environmental degradation apparent
from the toxicity study. For these reasons, the EPA and the
NJDEP chose a remedial objective for the groundwater based on the
protection of the north branch of Squankum Brook rather than
human consumption of the groundwater. The quantitative remedial
objectives, or cleanup goals, for groundwater are presented in
Table 2.
The cleanup goals are derived from the limits that would be
allowed for a discharge to the north branch of Squankum Brook at
the site under a New Jersey Pollution Discharge Elimination
System (NJPDES) permit. Although the Kirkwood Aquifer has been
designated a Class IIA aquifer (current drinking-water source)
under the EPA's proposed Groundwater Classification System, the
contaminant plume at the Bog Creek Farm site is an isolated
pocket of this aquifer, separated from the portion of the aquifer
used as a drinking-water source by hydraulic barriers described
previously. Therefore, the more stringent requirements, maximum
contaminant levels (MCLs), established by the Safe Drinking Water
Act were not considered appropriate for the plume at Bog Creek
Farm.
The toxicity study demonstrated that contamination in the brook
sediments may have a detrimental impact on biota in the brook. A
remedial objective was established to mitigate the hazard posed
by the contamination in the brook sediments. Although the con-
taminated sediment will be removed to restore the environmental
quality of the brook, there is no quantitative goal associated
with this remedial objective, as the exact level of contamination
that causes the environmental impact has not been determined and
there is no regulatory standard to guide the cleanup of the brook
sediment.
In summary, there are two remedial objectives (one for ground-
water and one for sediments) for the second operable unit
remedial action at Bog Creek Farm. The quantitative cleanup
goals for the groundwater are presented in Table 2. In removing
contaminated groundwater, much of the contamination detected in
the saturated soil will also be removed. Much of the contami-
nation in the unsaturated soil (above the water table) will be
washed into the aquifer with infiltrating rain water and would be
removed with the groundwater. Methods for addressing the con-
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TABLE 2
GROUNDWATER CLEANUP GOALS
Parameter (units)
Total Organic Carbon [TOC] (mg/1)
Biochemical Oxygen Demand - 5 day
[BOD5] (mg/1)
Petroleum Hydrocarbons (mg/1)
pH (s.u.)
«
Copper, Total (Mg/1)
Lead, Total (Mg/1)
Zinc, Total (M9/1)
Benzene (Mg/1)
Toluene (Mg/1)
1,1, 1-Trichloroethane (Mg/1 )
trans-l,2-Dichloroethene
Phenol
2,4-Dimethylphenol (Mg/1)
Acute Toxicity [LC50] (%eff)
Cleanup Goal
50 maximum
15 maximum
10 average
15 maximum
6.0 minimum
9.0 maximum
8 maximum
56 maximum
52 maximum
5 maximum
28 average
74 maximum
22 average
59 maximum
25 average
66 maximum
19 average
47 maximum
19 average
47 maximum
NMAT*
* No Measurable Acute Toxicity (NMAT) - less than 10% mortality
in all concentrations including 100% effluent
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taminated sediment in the north branch of Squankum Brook were
also evaluated in the supplemental FS.
DESCRIPTION OP ALTERNATIVES
The supplemental feasibility study considered remedial alterna-
tives to address two areas of concern at the site: contaminated
groundwater and contaminated sediments in the north branch of
Squankum Brook. A vide range of technologies was considered to
address the remedial-objectives for both of these areas. The
technologies that were not eliminated from consideration during
screening were assembled into remedial alternatives. These
alternatives were also screened in accordance with §300.430(e) of
the National Oil and Hazardous Substances Pollution Contingency
Plan (NCP), 40 CFR 300.430(6), the regulations for implementing
the Superfund program.
6roundvat«r
GW-1 No Action
Under this alternative, no active mitigation of the groundwater
contamination would be implemented. The quality of the
groundwater would be monitored through periodic sampling of
existing monitoring wells.
Groundwater contaminants would continue to migrate to the north
branch of Squankum Brook, eventually restoring the water table
aquifer at the site. However, the discharge of contaminants to
the brook appears to have an adverse impact on the biotic com-
munity in the brook. Therefore, this alternative does not
achieve the remedial objective of protecting the north branch of
Squankum Brook from the discharge of contaminated groundwater.
Squankum Brook leads to the Manasquan River, where a water supply
reservoir is currently under construction. However, chemical
analyses of samples from the Manasquan River and the lower part
of Squankum Brook indicate that the site is not currently
affecting the quality of the water at the reservoir intake, which
is now being built.
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Annual monitoring would cost approximately $19,800. The present
worth of 30 years of monitoring and evaluation and presentation
of the data would be approximately $304,400.
Active Groundvater Remediation
Groundwater modeling performed during the supplemental feasi-
bility study indicates that extracting 60 gallons per minute
(gpm) of groundwater from three wells near the northern boundary
of the site would prevent any of the contaminant plume from
entering the brook and would pull in a minimal amount of clean
water from the surroundings. Treated water would be reinjected
upgradient of the plume to enhance the flushing of the contami-
nated aquifer. After flowing through the formation, the water
would be intercepted by the extraction wells again. Systems
using different pumping rates and extraction without reinjection
were also evaluated in the technology screening section of the
supplemental FS, but were not included in the detailed evaluation
of alternatives because pumping at 60 gpm with reinjection
provided for optimal remediation of the aquifer.
Several methods of treating the water were described in the sup-
plemental FS and costs were developed for two promising systems.
These two systems are described as alternatives GW-2 and GW-3
below. The technologies that were not incorporated into remedial
alternatives were eliminated from consideration based on tech-
nical considerations, such as effectiveness, implementability,
and cost.
Off-site treatment of the water at a Publicly-Owned Treatment
Works (POTW) was eliminated from consideration primarily because
the most expeditious groundwater restoration would be effected by
reinjecting the treated water. Therefore, on-site treatment is
preferred. Other negative factors associated with using a POTW
are the distance that the water would have to be pumped to enter
an existing sewage main and the likelihood that extensive
pretreataent would be required.
On-site treatment methods other than those utilized in alterna-
tives GW-2 and GW-3 were evaluated and found to be ineffective in
treating the type of wastes present at Bog Creek Farm. Oxidation
using ozone is one such treatment technology. A treatability
study was performed on water from Bog Creek Farm to determine the
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-15-
effectiveness of ozone in destroying the contaminants present at
the site. The study indicated that ozone would not b« effective.
The supplemental FS report contains the complete screening of
technologies.
In both active remediation alternatives (GW-2 and GW-3), the
discharge of contaminated water to the north branch of Squankum
Brook would be halted by altering the flow of groundwater in the
Upper Kirkwood aquifer in the contaminated area, i.e. the con-
taminated water would be extracted from the aquifer by pumping it
to the treatment system before it could reach the brook. The
extraction system would remain in operation until the site-
specific cleanup goals (Table 2) were attained. The remedy is
expected to be completed within ten years.
*
GW-2 Extraction of Contaminated Groundvater, Three-Stage
Treatment, and Reinjection
This remedial alternative would utilize a treatment option that
incorporates air stripping, hydrogen peroxide/ultraviolet
photolysis (H2O2-UV) oxidation, and carbon adsorption. Air
stripping would remove most of the volatile organic contaminants.
The gas.exhaust from the air stripper would pass through a vapor-
phase carbon adsorption unit before the air was emitted to the
atmosphere. The H2O2-UV oxidation would remove those contami-
nants not removable by air stripping or carbon adsorption
(particularly the highly soluble compounds, such as ketones).
Finally, the liquid-phase carbon adsorption unit would remove the
remaining organic contaminants. A schematic diagram, which shows
each of the treatment steps and the interconnection of each step,
is provided in Figure 4.
The concentration of dissolved chromium in groundwater samples
from wells MW-B, MW-G, and MW-16 exceeded the maximum concen-
tration for EP Toxicity (5 ppm), established under the Resource
Conservation and Recovery Act. If the concentration of chromium
in the groundwater entering the treatment system exceeds the EP"
Toxicity level, the water will be considered a hazardous waste.
The need for an additional process step to remove metals,
including chromium, will be evaluated in the remedial design.
The estimated cost of installing this system would be $1,709,000.
Annual operation and maintenance expenses would be approximately
-------
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ALTERNATIVE GW-2
-------
-17-
$663,000, resulting in an estimated present worth for this
alternative, based on ten years of operation, of $6,830,000.
GW-3 Extraction of Contaminated Groundwater, Two-Stage
Treatment, and Reinjection
The system utilized for this remedial alternative is similar to
the system described for alternative GW-2. However, it does not
include the air stripper. Therefore, the vapor-phase carbon unit
is not needed, but a larger H2O2-UV oxidation unit is required.
The capital cost is somewhat lower and the operation and mainte-
nance cost is somewhat higher than for GW-2. A schematic diagram
of the two-stage treatment system is provided in Figure 5.
The estimated cost of installing this system would be $1,244,000.
Annual operation and maintenance expenses would be approximately
$750,000, resulting in a present worth for this alternative,
based on ten years of operation, of approximately $7,040,000.
Sediment
In the summer of 1988, the EPA's Environmental Response Team
(ERT) collected water and sediment samples from the north branch
of Squankum Brook for chemical analysis as well as toxicity
testing. Toxicity tests were performed using two test organisms:
Daphnia maqna (water-flea) and Piroephales promelas (fathead
minnow). Elevated toxicity was reported for the Daphnia in the
extract from one of the sediment samples. The EPA and the NJDEP
decided to evaluate remedial alternatives to address the contami-
nated sediments because of their impact on the Squankum Brook
habitat.
8B-1 No Action
The No Action alternative would allow the contaminated sediment
to remain in place. This sediment is apparently hazardous to
biota in the brook.
Warning signs would be installed along the north branch of
Squankum Brook at an estimated cost of $250. Annual monitoring
and data reporting would cost approximately $21,100. The present
worth of this alternative would be approximately $324,600.
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CHEMICAL
FEED SYSTEM
COLLECTION
WELLS
COLLECTION *
TANK
M*
M202
SOLUTION
60* H2O2
METERING PUMPS
uv/
OXIDATION
CHAMBER
ELECTRICAL LOAD 180 KW
-REGENERATED/MAKEUP
ACTIVATED CARBON
TO REJECTION
TRENCH
« i«
^1 1
TREATED
CM TANK
. r
SP
ACTIVATED
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COLUMN
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ENT CARBON
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FOR REGENERATION
RETENTION TIME
6.0 MIN
UV TREATED
CW TANK
OD
I
FIGURE 5
PROCESS FLOW DIAGRAM
ALTERNATIVE GW-3
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-19-
8B-2 Excavation and On-8it« Zncinaration
This alternative would utilize the incinerator that will already
be on the site as part of the first operable unit to treat the
sediment. The estimated 90 cubic yards of contaminated sediment
would be a minor addition to the 15,000 cubic yards of material
being incinerated as part of the first operable unit.
The flow of surface water in the brook and groundwater that dis-
charges to the brook from the north and south would be diverted
during excavation to prevent contaminated sediment from being
washed downstream. The stream bed would be excavated from just
above sampling location S-2 to just downstream from sampling
location S-3. After excavation, the exposed material would be
sampled to determine the concentration of any remaining contami-
nants. The stream bed would be restored to its original contours
using clean sand or soil of a similar consistency to the existing
material. The cleaned sediments would be tested as specified in
the contract for the first operable unit remedial action, and
acceptably treated soil would be used as backfill in the waste-
trench excavation.
The estimated .cost of this alternative would be $97,000. No
operation and maintenance is required, so the present worth is
equal to the capital cost.
SB-3 Excavation and Off-ait* Incineration
For off-site incineration, the sediment would need to be packed
in drums at the site and removed to a permitted incinerator in
trucks. Proper planning of the route and schedule of trucks
should minimize any danger and inconvenience of trucking this
material from the site. The same construction practices and
limits of excavation that were described for alternative SB-2
would be used for this alternative.
The estimated cost of this alternative would be $272,800. As
with alternative SB-2, the present worth is the same as the
capital cost.
The remedial alternatives are listed, along with their associated
capital and operation and maintenance costs and present worths,
in Table 3.
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-20-
Table 3
Second Operable Unit
Summary of Remedial Alternatives and Estimated Costs
GROUNDWATER
Alternative
GW-1 No Action
GW-2 Extraction,
3-Stage Treat-
ment , and
Reinjection
Capital Annual
Cost Cost
$0 $19,800
1,709,000 663,000
Present
Worth
$304,400
6,830,000
GW-3 Extraction,
2-Stage Treat-
ment, and
Reinjaction
1,244,000 750,000
7,040,000
SEDIMENT
Alternative
SB-1
SB-2
No Action
Excavation &
Capital
Cost
$250
97,000
Annual
Cost
$21,100
0
Present
Worth
$324,600
97,000
SB-3
On-site
Incineration
Excavation &
Off-site •
Incineration
272,800
272,800
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-21-
8UMMARY OF COMPARATIVE ANALYSIS OP ALTERNATIVES
The alternatives described above were evaluated in a detailed
analysis that considered the nine criteria stipulated in the NCP.
These are:
1. Overall protection of human health and the environment
2. Compliance with applicable or relevant and appropriate
requirements (ARARs) of other Federal and State
environmental and public health laws
- 3. Long-term effectiveness and permanence
4. Reduction of toxicity, mobility, or volume of contaminated
media
5. Short-term effectiveness
6. Implementability
7. Cost
8. State acceptance
9. Community acceptance
The projected performance of each of the alternatives relative to
the nine criteria mentioned above is presented below.
Groundvater
GW-1 Mo Action
This alternative would not provide any protection to the
environment or public health. Although no public health risks
were identified for the discharge of contaminated grqundwater to
the brook at current levels, this discharge may cause environ-
mental degradation, such as stress to biota in the north branch
of Sguankum Brook.
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-22-
The NJDEP and the EPA developed site-specific cleanup goals for
the groundvater based on acceptable concentrations for the
discharge of contaminants to the north branch of Squankum Brook.
These criteria were adopted to provide protection to public
health and the environment. Groundwater modeling performed
during the supplemental FS indicates that the No Action alterna-
tive would not attain these cleanup goals for many years and the
attenuation of contamination in the aquifer through natural
migration of the plume would only move these contaminants to the
brook. This alternative would not effectively reduce the impact
of the site on the environment for the long- or short-term. It
also would not reduce the toxicity, mobility, or volume of the
contaminated water.
The monitoring program would be simple to implement and the cost
of this alternative is very low compared to the cost of active
remedial actions. The NJDEP expressed a preference for active
restoration of the aquifer, as is noted in the following dis-
cussion, and the community appeared to favor the preferred
alternative, as presented in the Proposed Plan and at the public
meeting.
Active Groundwater Remediation
In both active remediation alternatives (GW-2 and GW-3), short-
term protection would be achieved by immediately containing the
plume. The discharge of contaminated water to the north branch
of Squankum Brook would be halted by extracting the contaminated
groundwater from the aquifer before it could reach the brook.
The extraction system would remain in operation until the site-
specific cleanup goals were attained. In the long term, the
active remedies would be protective because the aquifer would be
restored to the levels stipulated in the remedial objectives.
It is estimated that it will take ten years to restore the aqui-
fer to the cleanup goals (Table 2). These goals were developed
considering all Federal and State ARARs. The system would be
operated in such a way as to comply with the operational require-
ments of Federal, State, and local laws, including requirements
pertaining to construction in a floodplain and treatment levels
for wastes similar to the groundwater.
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-23-
The active remediation alternatives would immediately contain the
plume and would eventually remove the contaminants through treat-
ment. Either alternative would provide a permanent remedy that
would effectively protect public health and the environment by
reducing the toxicity and volume of contaminated groundwater.
Both alternatives would remove contaminated water from the aqui-
fer and render it non-hazardous through chemical treatment.
The pumping scheme has been developed to contain the entire
contaminated plume of groundwater through the placement of the
wells and the determination of the pumping rate. Although the
restoration of the aquifer would take approximately ten years to
complete, these remedial alternatives are both effective in
containing the waste for the short term. Methods of expediting
the restoration of the aquifer were explored in the supplemental
fS, but these technologies were either not effective for the
conditions at Bog Creek Farm or involved increasing the risks at
the site. The two alternatives that were evaluated in detail
balance short-term effectiveness and protectiveness with the goal
of expeditiously achieving a permanent remedy.
The installation of the wells and the treatment system would
involve only established, readily implementable technologies.
Both the three-stage (GW-2) and two-stage (GW-3) treatment
systems are fairly simple to operate, although the three-stage
treatment process utilizes air stripping, which is a more proven
technology for removing the volatile contaminants from the water.
The restoration of the aquifer also depends on the successful
extraction of the contaminants from the formation through extrac-
tion of the groundwater. The modeling performed during the sup-
plemental feasibility study indicates that the pumping scheme is
expected to effectively accomplish this goal.
The NJDEP was directly involved in the planning and performance
of the supplemental RI/FS, and the EPA and the NJDEP worked
together to establish the remedial objectives. State concurrence
on the preferred remedy was obtained before the Proposed Plan was
released. The State has indicated their acceptance of the remedy
selected in this ROD in a letter to the Regional Administrator of
EPA, Region II. This letter is contained in the Administrative
Record for the Bog Creek Farm site.
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-24-
The objective of the community relations activities was to inform
the public about the work being performed at this site and to
seek input from the public on the remedy. Issues raised at the
public meeting and during the public comment period are addressed
in the Responsiveness Summary section of this ROD.
The costs of the two active groundwater remedial action alterna-
tives are similar, as shown in Table 3. The estimated capital
cost of GW-2 is slightly higher, but the operation and main-
tenance expenses are less. As a result, the lifetime cost
(present worth) of GW-2 is expected to be slightly less than for
GW-3.
Sediment
8B-1 No Action
This alternative would allow the contaminated sediment to remain
in the brook where it adversely affects the animal community.
The No Action alternative would not offer any protection or
remediation to the environment of the north branch of Squankum
Brook, which has already been contaminated.
Although there are no ARARs to guide the remedial action for the
sediment, the No Action alternative would fail to address the
remedial objective for this medium. The NJDEP and the community
have indicated a preference for active remediation of the brook
as opposed to this alternative.
Active Sediment Remediation
The two excavation alternatives that were evaluated in detail
differ in that alternative SB-2 would treat the sediment in the
incinerator that will be on-site as part of the first operable
unit remedial action, while SB-3 would remove the sediment to an
off-site facility for permanent destruction of the contaminants.
The protectiveness and long-term effectiveness of the two
.alternatives are the same, as the same construction techniques
would be used to remove the same amount of contaminated material.
Both alternatives would provide protection of human health and
the environment by removing the contaminated material from the
brook. The stream bed would be replaced with sand of a similar
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-25-
consistency to the naterial that is currently in place. The new
stream bed material would eventually support a biotic community
similar to that which was present before it was affected by the
site.
Both of the excavation alternatives should provide effective,
permanent remedies. The contaminated material would be removed
from the brook and the organic contaminants would be destroyed
through incineration, thereby reducing the toxicity of the
material. In both alternatives, the contaminated material would
be handled and treated in accordance with operating procedures
established by the Resource Conservation and Recovery Act.
The on-site incinerator that would be utilized for alternative
SB-2 is currently being approved for the first operable unit.
The brook sediments that would be treated under alternative SB-2
are very similar to the material that will be treated under the
first operable unit. Therefore, additional approvals will not be
required for the additional material that would be incinerated as
part of this alternative.
Short-term protection will be achieved by temporarily diverting
the brook and groundwater flow into the brook during excavation
to allow dry excavation and to ensure that contaminated sediment
is not transported downstream. Excavation of the contaminated
sediment would involve only established construction practices
and diversion of the small brook should be accomplished easily.
Both incineration options are also readily implementable.
Alternative SB-2 is the least expensive alternative for the brook
sediment because the incinerator will already be present and
operating at the site. The State and the community have indi-
cated their acceptance of on-site incineration (alternative SB-2)
in their acceptance of the preferred remedy.
THE SELECTED REMEDY
The selected remedy incorporates alternative GW-2 (Groundwater
Extraction, Three-Stage Treatment, and Reinjection) and alterna-
tive SB-2 (Sediment Excavation and On-site Incineration). This
overall remedy will address the contaminants that have already
reached the sediment in the brook as well as those that are still
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-26-
in the subsurface formation at the site. The contaminants in the
plume will be contained in the short term by the groundwater
extraction system and will eventually be removed and treated by
the system. The sediment removed from the brook will be
incinerated to permanently remove and treat the contaminants.
The evaluation of the alternatives in the previous section dis-
cussed each of the alternatives relative to the criteria estab-
lished in the Comprehensive Environmental Response, Compensation,
and Liability Act of 1980, as amended, (CERCLA) and the NCP. The
selected remedy will provide protection of public health and the
environment. Site-specific groundwater cleanup goals (Table 2)
were developed by the EPA and the NJDEP to protect the north
branch of Sguankum Brook, the surface water that receives the
contaminated water from the aquifer at the site. These goals
will also form the endpoint for the groundwater restoration.
The three-stage groundwater treatment in alternative GW-2 was
selected as it offers more certain treatment than the process in
GW-3. Treatability tests on groundwater from the site have shown
that air stripping and carbon adsorption can effectively remove
most of the contaminants present in the groundwater. The H2O2-UV
oxidation will provide treatment of those chemicals that might
not be removed by air stripping or carbon adsorption and will
also reduce the consumption of carbon by treating some contami-
nants before the water enters the carbon adsorption unit.
Groundwater modeling has indicated that extracting 60 gpm of
water from three wells placed near the northern border of the
site (Figure 6) will provide a cost-effective means of restoring
the aquifer. The selected treatment system utilizes air strip-
ping, H2O2-UV chemical oxidation, and carbon adsorption to treat
or remove the contaminants from the water. The treated water
will be reinjected on site, upgradient of the waste-disposal
area.
On-site incineration of the contaminated sediments was selected
based on the presence of an incinerator at Bog Creek Farm as part
of the first operable unit. Since the incinerator will already
be mobilized to the site, this option will be less costly and
easier to implement than off-site incineration.
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NORTH
4 KIT D€ff TRENCH
AND PERFORATE6
I
K>
GROUNDWATER ELEVATION
CONTOUR LINES
REMEDIATED IN 1« OPEHABLE UNIT
FIGURE 6
OMOUNDWATER PUMPING AND
TREATMENT LAYOy? AT BOG CREEK FARM
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-28-
The sediment excavation will be performed as close to the end of
the first operable unit as practical. The groundvater remedia-
tion will then be initiated as soon after the first operable unit
as possible to reduce the amount of contaminants that will reach
the brook before the groundwater-extraction system cuts off the
flow of contaminated groundwater.
The material below the excavation will be analyzed to determine
the amount of contamination remaining in the environment. After
the groundwater remediation has begun, the sediment will be
sampled again to determine whether the discharge of contaminated
groundwater occurring between the sediment excavation and the
groundwater remediation had any effect on the sediment. These
data, as well as the results of the groundwater monitoring during
the aquifer restoration, will be reviewed by the EPA and the
NJDEP to determine the success and the progress of the remedial
actions. These data will also be supplied to the public
periodically as part of the public awareness program associated
with this remedy.
A detailed breakdown of the estimated costs for the principal
elements of the selected remedy is provided in Table 4.
STATUTORY DETERMINATIONS
Section 121 of CERCLA stipulates certain factors that must be
considered in evaluating remedial alternatives. It also
establishes certain requirements that must be achieved by the
selected remedy. These requirements were considered in the
development of the remedial objectives as well as in the
development and evaluation of the remedial alternatives.
The selected remedy will remove contaminants from the aquifer and
the brook sediment to protect the environment and attain ARARs.
The public health risk assessment indicated that the contaminants
remaining at the site after the first operable unit do not pose a
significant risk to public health because of the limited exposure
pathways. However, the contaminated groundwater and.brook sedi-
ment constitute existing environmental impacts. The selected
remedy offers immediate protection from migration of contaminants
in that the contaminated sediment will be removed and the ground-
water will be contained by the extraction system as it is being
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-29-
Table 4
Cost Summary for the Selected Remedy
Estimated Capital Costs Cost
Groundwater
1. Support Facilities $64,800
2. Pumping & Collection System 133,600
3. Air Stripper 94,900
4. Vapor-Phase Carbon 360,700
5. H202-UV Oxidation 127,400
6. Liquid-Phase Carbon 141,300
¥
7. Reinjection System 147,800
8. Building 95,000
9. Utilities 180.000
Groundwater Total Direct Construction Cost (TDCC) $1,345,500
Contingency (§ 20% of TDCC) 269,100
Engineering (§ 5% of TDCC) 67,300
Legal & Administrative (§ 2% of TDCC) 26.900
Groundwater Total Capital Cost $1,708,800
Sediment
1. Groundwater Diversion Trenches $33,700
2. Sediment Excavation & Hauling (90 cy) 4,500
3. Incineration (90 cy) 34,500
4. Clean Soil (for Backfill) 1,800
5. Treated Sediment Disposal (On site) 900
6. Utilities 1.000
Sediment Total Direct Construction Cost (TDCC) $76,400
Contingency (§ 20% of TDCC) - 15,300
Engineering (§ 5% of TDCC) 3,800
Legal & Administrative (§ 2% of TDCC) 1.500
Sediment Total Capital Cost $97,000
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-30-
Table 4 (continued)
Estimated Operation and Maintenance fO&Ml Costs* Annual Cost
Groundwater
1. Performance Monitoring $44,400
2. Pumping & Collection System 3,000
3. Air Stripper 39,100
4. Vapor-Phase Carbon 62,900
5. H2O2-UV Oxidation 95,200
6. Liquid-Phase Carbon 13,600
*
7. Reinjection System 2,600
8. Maintenance (6 8% of TDCC) 107,600
9. Labor 263.000
Subtotal Groundwater O&M Cost $631,400
Contingency (§ 5% of O&M Cost) 31.600
Total Groundwater O&M Cost $663,000
Sediment
No O&M is required
Net Present Worth and Discount Rate (10%)
Groundwater $6,830,000
Sediment 97.000
Total $6,927,000
*Based on ten years of groundwater treatment.
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-31-
treated. Temporarily diverting the north branch of Squankvun
Brook and the groundwater that feeds the brook will prevent
contaminated sediment from being washed downstream during the
excavation, thereby addressing concerns relative to short-term
risks.
The remedial objectives were developed based on the public health
risk assessment and the assessment of environmental impacts while
considering Federal and State ARARs. There are no ARARs to act
as endpoints for the sediment remediation. However, the ground-
water cleanup goals were established based on the State's
requirements for protecting the north branch of Squankum Brook,
the receptor affected by the contamination in the aquifer at the
site.
Although the Kirkwood formation is used as a source of potable
water, the contaminant plume is limited to a very small area at
the site by physical factors, described previously. Therefore,
it was determined that the Maximum Contaminant Levels established
by the Safe Drinking Water Act are not applicable or relevant and
appropriate for this action. Rather, the established limits for
discharge to the north branch of Squankum Brook, the receptor of
the contaminated water, are the relevant and appropriate
standards for the cleanup of the groundwater.
The selected remedy will prevent any discharge of groundwater
from the site to the north branch of Squankum Brook while the
groundwater extraction system is in operation. At the same time
the treatment system will restore the aquifer to the relevant and
appropriate standards. The groundwater extraction and treatment
system will remain in operation until these standards have been
met.
The cleanup goals for groundwater are derived from the limits
that would be allowed for a discharge to the north branch of
Squankum Brook at the site under a New Jersey Pollution Discharge
Elimination System (NJPDES) permit. Although the Kirkwood Aqui-
fer has been designated a Class IIA aquifer (current drinking-
water source) under the EPA's proposed Groundwater Classification
System, the contaminant plume at the Bog Creek Farm site is an
isolated pocket of this aquifer, separated from the portion of
the aquifer used as a drinking-water source by hydraulic barriers
described in the Summary of Site Characteristics in this docu-
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-32-
nent. Therefore, the more stringent requirements, maximum con-
taminant levels (MCLs) , established by the Safe Drinking Water
Act were not considered appropriate for the plume at Bog Creek
Farm.
The selected remedy will be designed to comply with any operating
standards that are ARARs. Treatment of contaminated water will
comply with the requirements of the Resource Conservation and
Recovery Act to the extent that the groundvater at the site is a
hazardous waste. The sediments will be treated in the incinera-
tor that is currently being approved for the first operable unit.
Reinjection of the treated water will comply with the NJDEP's
standards for reinjecting treated water. All operations that
will occur in the floodplain of the north branch of Squankum
Brook will be designed to minimize any impact on the brook and
the associated wetlands and to prevent any disruption of the
operation that might occur in the event of a flood.
The two alternatives that comprise the selected remedy (GW-2 and
SB-2) are the most cost-effective means of achieving the remedial
objectives. The sediment excavation and incineration will be
coordinated with the ongoing remedial action and will only form a
small addition to that project. The groundwater remedy uses the
three-stage treatment that, in addition to being a more estab-
lished treatment process, is slightly less expensive than the
system described in alternative GW-3.
The selected remedy will provide a permanent remedy at the site,
as treatment technologies (incineration and H2O2-UV oxidation)
will be used to destroy the contaminants. The activated carbon,
which will be used to capture the contaminants removed from the
water in the air stripper as well as in the liquid-phase carbon
adsorption unit, will be regenerated off site. In attaining the
remedial objectives, the selected remedy will provide a permanent
solution that is protective of public health and the environment
and that utilizes treatment to detoxify the contaminated media.
-------
Responsiveness Summary
Bog Creak Farm
The Environmental Protection Agency held a public meeting at the
Hovell Township Municipal Building on May 22, 1989. The remedial
investigation and feasibility study (RI/FS) and the Proposed Plan
for the second operable unit, as well as the current status of
the first operable unit, were presented at this meeting. A
public comment period was held from May 15 to June 16, 1989 in
connection with the release of the second operable unit RI/FS and
Proposed Plan.
The following sections categorize the comments received into
general issues. Many of the comments raised at the public
meeting pertain to the first operable unit, particularly the
operation of the on-site incinerator. As these comments are not
related to the second operable unit, they are not incorporated in
the ROD itself. However, they are presented and addressed in
this Responsiveness Summary.
Manasquan River Reservoir
Several comments reflected the community's concern that the
Manasquan River Reservoir, which is under construction, may be
affected by contamination from Bog Creek Farm. The timing of the
remedial action at Bog Creek relative to the opening of the water
intake for the reservoir (scheduled for next Spring) was also a
concern.
The surface water analysis performed by the EPA for the first
operable unit RI/FS (1984 data) indicated that the contaminants
entering the north branch of Squankum Brook were volatilized and
diluted before reaching the Manasquan River and, therefore, would
not affect the reservoir. The samples collected from the north
branch of Squankum Brook as part of the current RI/FS support
this conclusion. The EPA does not believe that the water
diverted from the Manasquan River for the reservoir will have any
detectable quantity of contaminants from the Bog Creek Farm site.
The reservoir was mentioned in the Proposed Plan to document that
this issue had been considered in developing the preferred
alternative. It was not the intention of the EPA to alarm the
public with concern that the site has an adverse impact on the
quality of the water that will be collected in the reservoir.
-------
The EPA has been working with the New Jersey Water Supply
Authority, the agency responsible for the Manasguan Water Supply
System, regarding the cleanup of Superfund sites that potentially
may affect the quality of water in the Manasguan River. The
implementation of the first operable unit and the removal of
contaminated sediment from the north branch of Squankum Brook
should be completed well before the reservoir intake is opened.
Although the aquifer restoration will not be completed for
several years, the extraction, treatment, and reinjection system
should be installed and effectively contain the plume by next
summer. However, even without treatment the site has had no
measurable effect on the water quality of the Manasguan River.
Cleanup Standards
The origin of the site-specific groundwater cleanup goals
(Decision Summary* Table 2) was questioned. A particular issue
was raised whether the EPA would abide by State standards that
are more stringent than Federal standards.
The EPA worked closely with the New Jersey Department of Environ-
mental Protection (NJDEP) in performing the supplemental RI/FS,
including the selection of the remedial objectives and quanti-
tative cleanup goals. The remedial objective for the aquifer
restoration is to protect the north branch of Squankum Brook from
the discharge of contaminated groundwater. Accordingly, the
State's requirements for a point source discharge for the site
were used for the groundwater cleanup goals.
The parameters used for the standards are the same ones that
would be used for a discharge to this brook at the site. These
numbers were derived considering the protection of the sensitive
non-human receptors in the brook. The supplemental RI/FS indi-
cates that there is not a human health threat at current levels.
Effect of the Site on Residential Wells
Two different issues were raised at the public meeting related to
the effect of the site on residential wells. A nearby resident
questioned whether the site was affecting any residential wells
currently, and a member of the town council asked whether the
-------
groundwater extraction system would affect the yield of water-
supply wells.
As part of the 1985 RI/FS, five residential wells near the site
were sampled. No contaminants from the site were detected in any
of these wells. Subsequent hydrogeologic studies found that the
contaminant plume is limited to a small portion of the shallow
aquifer. The contaminants travel to the north from the waste-
disposal area and are entirely intercepted by the north branch of
Squankum Brook. No residential wells are located between the
waste-disposal area and the brook, so none are threatened by the
site.
The groundwater extraction system has been planned, based on
groundwater modeling performed during the supplemental RI/FS, to
contain the contaminated plume while withdrawing the minimal
amount of clean water. At the same time, the treated water will
be reinjected just upgradient from the waste-disposal area.
Therefore, the groundwater extraction should have no effect on
any water supply wells in the area.
Reinjection
It was noted that reinjection of treated water was not favored
previously at other sites in this part of Monmouth County. The
question arose why Bog Creek Farm was more suited to the use of
this technology.
The same hydrogeologic features that have contained the plume
also make this site amenable to the use of reinjection of the
treated water. The contaminated area is fairly small, and the
groundwater flow pattern will make it possible to capture the
entire plume in the extraction system. Reinjecting the treated
water will not force the plume to travel outside of the area that
can be captured by the extraction system. Reinjection will
expedite the restoration of the aquifer by replacing the contami-
nated water, which will be removed from the aquifer, with clean
water from the treatment system, thereby allowing the extraction
system to remove water without drawing the water table down below
the main body of contamination.
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Disposal of Ash
The EPA was asked whether ash from the incinerator would be
removed from the site, and if so, what steps had been taken to
ensure adequate disposal capacity off-site.
The remedial design for the first operable unit stipulated strict
standards for the use of the ash as backfill in the excavation at
the site. The incinerator should be able to easily remove the
contaminants from the soil leaving clean material that can be
returned to the site. If for any reason any ash does not meet
the standards established, the contractor will have the option of
subjecting it to additional treatment or removing it from the
site for disposal in a landfill permitted to accept hazardous
waste.
All of the treated soil will be used as backfill in the uplands
portion of the site. The brook will be restored to its original
grade using clean material imported to the site.
The construction contractor is responsible for the ultimate dis-
posal of any material that must be removed from the site. The
specifications for this action require the contractor to identify
the disposal facility he intends to use. Any material that is
removed from the site will be packed and transported as required
by the appropriate regulations.
Future Use/Grading
Several comments addressed restrictions on the future use of the
site. A related issue concerns the plan for regrading and
revegetation of the site after the remedial action.
The contract for the first operable unit remedial action speci-
fies the restoration of the site after the completion of con-
struction. The site will be restored to its original grade with
the exception that the sharp drop into the bog will be replaced
with a gradual slope to the north branch of Squankum Brook. This
change in slope was required by the ROD for the first operable
unit to prevent contaminated groundwater from collecting in the
bog area again. The pond, which was installed as an early
remedial action, will be eliminated for the same reason. The
site will be revegetated with native grasses.
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During the restoration of the aquifer, some restrictions on the
use of the site will be required to protect the pumps and the
treatment system. In general, however, the use of the site will
be determined by the owner of the property. After the .completion
of the second operable unit, the EPA does not foresee the need
for any restrictions on the use of the site but may recommend
that drinking-water wells not be installed in the former waste-
disposal area.
Biological Survey
The EPA was asked whether a biological survey was performed to
determine what species were present in the north branch of
Squankum Brook and whether the site had any impact on activity or
species diversity. A related question requested clarification of
the results of the toxicity study.
The EPA did perform a biological survey of the north branch of
Squankum Brook before the toxicity study was performed. This
rough survey found no impact on the number of individuals or the
diversity of species. The EPA's Biological Technical Assistance
Group is preparing a summary of this survey. The summary will be
sent to public repositories when it is available.
The toxicity study found elevated toxicity for one test organism
(water flea) in one sample. The other test organism (fathead
minnow) exhibited no elevated toxicity in any of the samples.
Long-Term Monitoring
One question addressed the duration of long-term monitoring after
the completion of the aquifer restoration.
The aquifer will be monitored as long as necessary to ensure that
the groundwater cleanup goals have been achieved. Once this is
accomplished, further monitoring of the aquifer will no longer be
required.
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Air Quality/Monitoring
Several comments reflected the public's concern about air quality
during the first operable unit (excavation and incineration) and
the second operable unit (water treatment). Specific questions
addressed the level of emissions from the incinerator and the
design of the monitoring program.
The incinerator, as well as the rest of the construction system
that will be used to implement the first operable unit, has been
designed to minimize emissions. The incinerator and the water
treatment plant will both be carefully controlled and all vapors
and dust will be treated using extensive air pollution control
equipment. Emissions from the excavation itself are more
difficult to control, but the size of the open excavation will be
limited to minimize vapor and dust emissions, and the air
immediately outside of the excavation will be monitored. Any
emissions will be controlled by wetting the open face of the
excavation or using other construction practices as necessary.
Air monitors will also be placed at the perimeter of the site to
record the level of any emissions. Although the normal operation
of the incinerator and air pollution control equipment should
prevent the release of any hazardous material, the incinerator is
equipped with many safeguards and automatic controls to respond
to any disturbance of normal operations. Air monitoring data
will be supplied to Township officials; coordination with local
emergency management personnel is addressed as a separate issue
below.
Construction will not begin at the site until the contractor has
satisfied the EPA and NJDEP regulatory authorities that the
incinerator will perform up to the standards established in the
remedial design. Part of the approval process involved modeling
the emissions of vapors and particulate matter from all sources
at the site during the remedial action. In response to a request
from Township officials, the EPA supplied a copy of this model to
the public. After the equipment is installed at the site, it
will be tested in a trial burn using known material. Operations
will only begin after the results of the trial burn have been
accepted by the EPA and the NJDEP.
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Coordination vith Local Emergency Management Agencies
The EPA was requested to coordinate all construction activities
with local emergency management agencies, and to supply all moni-
toring results to the Township.
The EPA's construction contractor has already had some contact
with the local emergency management agencies. The EPA intends to
follow up with discussions with local officials and will prepare
a plan to outline coordination of all parties in the result of an
emergency at the site. In addition, the EPA will coordinate with
local officials the routes and times used by any truck traffic to
or from the site. The EPA will also establish a system for
reporting monitoring information to the township and for noti-
fying the township of any release of hazardous materials from the
site.
On-Site Incineration
Several questions were related to the operation of the
incinerator at the site. In particular, there were questions
about the duration of the operation at the site and whether any
waste would be brought from other sites to the incinerator at Bog
Creek Farm.
A transportable incinerator will be brought to the Bog Creek Farm
site for the sole purpose of implementing the remedial action at
this site. No material will be brought to the site from other
locations to be incinerated. The contractor has indicated that
it will take approximately two to four months to incinerate the
material at the site.
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ADMINISTRATIVE RECORD INDEX
June 1989
Bog Creek Farm
Remedial Action Master Plan (RAMP), NUS Corporation, April 1983
Community Relations Plan, NUS Corporation, June 1983
RI/FS Work Plan, NUS Corporation, February 1984
Site Operations Plan, NUS Corporation
Remedial Investigation (RI), Volume 1, NUS Corp., August 1986
Remedial Investigation (RI), Volume 2, NUS Corp., August 1986
Feasibility Study (FS), NUS Corporation, August 1986
Feasibility Study Addendum, NUS Corporation, September 1986
Record of Decision (ROD), September 30, 1985
Remedial Design (RD) Work Plan, Ebasco Services, June 1987
Request For Proposal (RFP), U.S. Army Corps of Engineers,
August 1988
Supplemental RI/FS Work Plan, Ebasco Services, November 1986
Supplemental RI/FS and RD Field Operations Plan, Ebasco Services,
November 1986
Supplemental RI, Ebasco Services, February 1989
Toxicity Study, EPA Environmental Response Team, February 1989
Supplemental FS, Ebasco Services, April 1989
Proposed Plan, EPA, May 1989
Public Meeting Fact Sheet, EPA, May 1989
Public Notice, Asbury Park Press. May 18, 1989
Correspondence from Anthony Farro, NJDEP, to John Frisco, EPA,
February 2, 1989, re: Remedial Action Objectives
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