United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
PB93-963801
EPA/ROD/R02-92/169
March 1992
SEPA Superfund
Record of Decision;
Ramapo Landfill, NY
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NOTICE
The appendices listed in the index that are not found in this document have been removed at the request of
the issuing agency. They contain material which supplement, but adds no further applicable information to
the content of the document All supplemental material is, however, contained in the administrative record
for this site.
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50272-101
REPORT DOCUMENTATION
PAGE
1. REPORT NO.
EPA/ROD/R02-92/169
a Red ptenfa Accession No.
4. TMeandSuMMe
SUPERFUND RECORD OF DECISION
Ramapo Landfill, NY
First Remedial Action - Final
S. Report Date
03/31/92
7. Aumor(s)
8. Popfofmlno OigtuiLuillon Ropt. No*
9. Pertomilng Orgabibaaon Nome and Address
10. ProJecVTask/WerkUnltNo.
11. Contract(C)orCaa«.t(G)No.
(C)
12. Sponsoring Organization Nome and Address
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report « Period Covered
800/000
14.
15. Supptomentary Notes
PB93-963801
16. Abstract (UnA: 200 weeds)
The 60-acre former landfill site is located on a 96-acre tract in the Town of Ramapo,
Rockland County, New York, about 35 miles northwest of New York City. Utility
corridors lie on three sides of the site, including high-voltage power transmission
lines. A high-pressure gas line is to the south; a pistol range, northeast; and a
power substation, north of the site. Surface water bodies in the site area include
the Ramapo River, Torne Brook, and Candle Brook. The Ramapo River may be used as a
drinking water source, and Torne Brook is suitable for primary contact recreation.
The landfill consists of two major lobes that are steeply sloped toward the Ramapo
River and Torne Brook. Groundwater is withdrawn from the area south and west of the
site for residential use. Ten water supply wells, operated by the Spring Valley Water
Supply Company and serving a population of over 200,000, are located along the Ramapo
River both upstream and downstream of the site. Several of these wells are located
within 1,500 feet of the landfill; the closest lies approximately 500 feet west of the
site. Prior to landfill operations in the 1950's and 1960's, portions of the site
were excavated as a gravel source, and in 1971, the Rockland County Department of
Health granted a permit to the Town of Ramapo for the operation of the sanitary
(See Attached Page)
17. DC
m Analysis a Descriptors
NY
Record of Decision - Ramapo Landfill,
First Remedial Action - Final
Contaminated Media: soil, gw, sw
Key Contaminants: VOCs (benzene), other organics, metals (arsenic, chromium, lead)
b. MentMers/Open-Ended Terms
c. COS ATI HelOTGroup
18. AvaUabUty Slate
nt
19. Security Class (This Report)
None
20. SecurityOass(TMsPage)
None
21. No. of Pages
64
22. Pltce
(See AMSM39.18)
See tnstrucSana on Reverse
OPTIONAL FORM 272 (4-77)
(Formerly NTIS3S)
Di^iii uimiii ot Cornrnorco
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EPA/ROD R02-92/169
Ramapo Landfill, NY
First Remedial Action - Final
Abstract (Continued)
landfill. Until 1984, municipal waste was accepted in the landfill, and construction
and demolition debris was accepted at the site until 1989. An offsite leachate
collection system, constructed in 1984, currently discharges an average flow of
80,000 gallons per day to the Village of Suffern Wastewater Treatment Plant. The site
is currently being used as a compaction and transfer facility by the Town of Ramapo.
Trash and debris are weighed at a weigh station/guardhouse, compacted at a baler
facility in the northeastern corner ofthe site, and transferred to the Al Turi Landfill
in Goshen, New York. This ROD represents the entire remedial action for the site by
controlling source of contamination and the generation of leachate, and treatment of
contaminated ground water. The primary contaminants of concern affecting soil, ground
water, and surface water are VOCs, including benzene; other organics; and metals,
including arsenic, chromium, and lead.
The selected remedial action for this site includes installing a multi-media cap over
the 60-acre landfill; improving the existing leachate collection system; diverting
surface water drainage; and relocating and/or raising Torne Valley Road to allow for
filling rather than excavating the landfill side slopes in order to achieve stable
slopes; installing ground water extraction wells to supplement the existing leachate
collection system and off-site treatment at the Suffern Wastewater Treatment Plant;
long-term monitoring of ground water, surface water and perimeter air monitoring and
venting or control, as required. If necessary, an alternate water supply would be
provided. This contingency alternative requires the development of rapid
implementation plans and preliminary design of the alternate water system. The
estimated present worth cost for this remedial action is $21,410,000 to $28,050,000,
which includes an annual O&M cost of $319,800 to $678,600 for 30 years. The higher
cost estimate reflects the implementation of optional components of the selected
remedy, including an alternate water supply, ground water pretreatment and treatment of
landfill gases.
PERFORMANCE STANDARDS OR GOALS: Chemical-specific goals for leachate and shallow
ground water clean-up are based on the more stringent New York State Water Quality
Criteria standards for VOCs (benzene); other organics; and metals (arsenic, chromium,
lead) . Surface water standards are based on human and aquatic ARARs, whichever is more
stringent.
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ROD FACT SHEET
SITE
Name:
Location:
HRS Score:
ROD
Date Sighed:
Remedy:
Capital Cost:
O & M Cost:
Present Worth Cost:
LEAD
NYSDEC
Primary Contact:
Secondary Contact:
Main PRPs:
WASTE
Type:
Medium:
Origin:
Est. Quantity:
Ramapo Landfill
Town of Ramapo
44.73
March 31, 1992
Landfill Cap/Leachate & GW
Collectioh/Off-site Treatment
$18,390,000 - $21,640,000
$319,800 - $678,600
$21,410,000 - $28,050,000
Robert Nunes (212) 264-2723
Joel Singerman (212) 264-1132
Town of Ramapo
Volatiles, Semi-Volatiles,
Inorganics
Soil, groundwater, surface water
Municipal and hazardous wastes
Municipal Landfill Size: 60 acres
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RECORD OF DECISION
Ramapo Landfill Site
Town of Ramapo
Rockland County, New York
United States Environmental Protection Agency
Region II
New York. New York
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DECLARATION FOR THE RECORD OF DECISION
Site Name and Location
Ramapo Landfill, Town of Ramapo, Rockland County, New York
Statement of Basis and Purpose
This decision document presents the selected remedial action for the Ramapo Landfill site
(the "Site"), located in the Town of Ramapo, Rockland County, New York, which was
chosen in accordance with the requirements of the Comprehensive Environmental
Response, Compensation, and Liability Act, 42 U.S.C. §§ 9601-9675, as amended, and
to the extent practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan, 40 CFR Part 300. This decision document explains the factual and
legal basis for selecting the remedy for the Site. The information supporting this remedial
action decision is contained in the administrative record for the Site. The administrative
record index is attached (Appendix III).
The New York State Department of Environmental Conservation (NYSDEC) concurs with
the selected remedy. (See Appendix IV.) NYSDEC will also concur with the contingent
remedy, should the confirmatory studies determine that the contingent remedy is
appropriate.
Assessment of the Site
Actual or threatened releases of hazardous substances from the Site, if not addressed by
implementing the response action selected in this Record of Decision (ROD), may present
a significant and substantial endangerment to public health, welfare, or the environment.
Description of the Selected Remedy -.
This operable unit represents the entire remedial action for the Site. It addresses the
principal threats to human health and the environment at the Site by controlling the
source of contamination and the generation of contaminated leachate, as well as by
treating contaminated groundwater.
The major components of the selected remedy include:
Installation of a cap on the tops of the landfill using a multi-media system,
including layers of fill material, a gas-venting system and an impermeable
membrane. The landfill side slopes will be capped using a mufti-media
svstem without an imDermeable membrane, if confirmatory studies
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demonstrate that this approach meets remedial action objectives. Should
the confirmatory studies indicate that the overall remedy's effectiveness
would be significantly reduced by not including an impermeable barrier in
the multi-media cap on the sideslopes, then an impermeable barrier would
be included in the cap on some or all of the side slopes of the landfill;
Installation of groundwater extraction wells to supplement the existing
leachate collection system;
Collection and diversion of leachate seeps to the leachate collection system
for off-site treatment;
Installation of a perimeter drain around the sections of the cap containing
the impermeable membrane to collect and divert surface water run-off;
If groundwater pretreatment is needed (pursuant to the requirements of the
off-site treatment facility), construction of a pretreatment facility which would
be tied into the existing leachate collection and discharge system;
Performance of air monitoring prior to, during, and following construction at
the Site to ensure that air emissions resulting from the cap construction
meet applicable or relevant and appropriate requirements. Perimeter.air
monitoring in the groundwater monitoring wells, piezometers, and additional
gas monitoring wells to be installed between the landfill and the Baler
Building will be performed. Landfill gas emissions will be controlled, if
necessary;
Imposition of property deed restrictions which will include measures to
prevent the installation of drinking water wells at the site, and restrict
activities which could affect the integrity of the cap;
Performance of a maintenance and sampling program upon completion of
closure activities. The monitoring program will provide data to evaluate the
effectiveness of the remedial effort. Additional monitoring points will be
established as heeded to detect any future movement of site contaminants
toward drinking water sources off-site;
Development of a contingency plan for rapid implementation of additional
measures to protect nearby residents and users of groundwater if those
measures are determined to be necessary.
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Declaration
The selected remedy is protective of human health and the environment, complies with
federal and state requirements that are legally applicable or relevant and appropriate to
the remedial action, and is cost-effective. This remedy utilizes permanent solutions and
alternative treatment technologies to the maximum extent practicable. In keeping with the
statutory preference for treatment as a principal element of the remedy, the contaminated
leachate and groundwater will be collected and treated. The landfill material, however,
cannot be excavated and treated effectively, because of the size of the landfill and
because there are no on-site "hot spots" that represent the major sources of
contamination.
A review of the Site will be conducted no later than five years after commencement of the
remedial action to ensure that the remedy continues to provide adequate protection of
human health and the environment, because this remedy will result in hazardous
substances remaining on-site above health-based levels.
—^W^^_^^^_^^^^B««. ^f __
X Constantino Sidamon-Eristoff 7 /Daf£
Reaional Administrator /
Regional Administrator
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DECISION SUMMARY
RAMAPO LANDFILL SITE
TOWN OF RAMAPO
ROCKLAND COUNTY, NEW YORK
United States Environmental Protection Agency
Region II
New York, New York
March 1992
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TABLE OF CONTENTS
SITE HISTORY AND ENFORCEMENT ACTIVITIES 2
HIGHLIGHTS OF COMMUNITY PARTICIPATION 4
SCOPE AND ROLE OF OPERABLE UNIT 4
SUMMARY OF SITE CHARACTERISTICS 5
SUMMARY OF SITE RISKS 7
DESCRIPTION OF REMEDIAL ALTERNATIVES 10
SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES '. 17
SELECTED REMEDY 23
STATUTORY DETERMINATIONS 26
DOCUMENTATION OF SIGNIFICANT CHANGES 30
ATTACHMENTS
APPENDIX I. FIGURES
APPENDIX II. TABLES
APPENDIX III. ADMINISTRATIVE RECORD INDEX
APPENDIX IV. NYSDEC LETTER OF CONCURRENCE
APPENDIX V. RESPONSIVENESS SUMMARY
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SITE NAME, LOCATION AND DESCRIPTION
The Site is located on a 96-acre tract in the Town of Ramapo, Rockland County, New
York, about 35 miles northwest of New York City, and 1 mile northeast of the Village of
Hillburn, New York. The Site location is shown on Figure 1 and a Site plan is depicted
in Figure 2. The Site is situated at the western base of the Ramapo Mountains off Torne
Valley Road east of the New York State Thruway, Route 17, and Route 59. Utility
corridors lie on three sides of the Site, high voltage power transmission lines to the east
and west, and a high-pressure gas line to the south. A power substation is located just
north of the Site.
Approximately 50 acres of the Site are covered with fill material. The landfill portion of the
Site is mounded into two major lobes (northern and southern), and slopes steeply toward
the west with grades ranging from less than one percent to greater than 30 percent.
Figure 3 depicts the location and depth of the landfill lobes. Both landfill lobes consist of
mixed refuse. Substances reportedly disposed of in the landfill portion of the Site include
industrial sludge and other wastes from a pharmaceutical company, sewage sludge,
municipal refuse, asbestos, construction and demolition debris, yard debris, paint sludge,
and liquid wastes from a paper company. Vegetative cover, although generally, thick,
varies from young trees to a mix of grasses and underbrush to bare ground. Areas along
the Site boundaries consist of mature hardwood forest.
An on-site leachate collection system consists of 4 main conduits located along -the
northern and western boundaries of the Site as shown in Figure 4. Three conduits are
located in the subsurface using perforated drain pipes. A 6-inch toe drain was installed
just beneath the ground surface at the toe of the landfill, using 2,933 feet of perforated
pipe. An 8-inch shallow underdrain was installed at a depth 8 to 10 feet below grade
using 4,023 linear feet of perforated pipe on the upslope side of Tome Valley Road. A
12-inch deep underdrain was installed between 10 and 25 feet deep using 4,259 linear
feet of both perforated and nonperforated pipe. The fourth conduit consists of a concrete
surface-water collector at the base of the landfill which enters a stormwater catch basin
located in the southwestern part of the Site near MH-A-5. The catch basin was
constructed and is maintained to prevent silt and other debris from entering the leachate-
collection system. This conduit handles surface seeps from the landfill and surface runoff
during storm events. The 4 collectors tie together near MH-A-5 (see Detail A on Rgure
4). A 6-inch force main connects to the leachate holding pond, while a 48-inch pipe leads
to Torne Brook (Former Outfall 002). This 48-inch pipe is designed to convey overflow
during heavy-water runoff from the concrete collector.
The Site is currently being used as a compaction and transfer facility by the Town of
Ramapo. Trash and debris are weighed at a weigh station/guard house along Tome
Valley Road, compacted at a baler facility in the northeastern corner of the Site, and
transferred to the Al Turi Landfill in Goshen, New York. A pistol range utilized by the
Town of Ramapo Police Department is also located in the northeastern area of the Site.
The main surface waters in the vicinity of the Site are the Ramapo River, Torne Brook,
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and Candle Brook (see Figure 2). The Ramapo River, located approximately 300 feet
from the southwest corner of the Site, is a NYSDEC Class "A" waters, which may be used
as a source of water supply for drinking, culinary, or food-processing purposes. Torne
Brook, which flows near the western boundary of the Site, and Candle Brook, a tributary
of Torne Brook, are NYSDEC Class "B" waters, suitable for primary contact recreation and
any other use, except as a source of water supply for drinking, culinary, or food-
processing purposes. Figure 5 depicts the 100-year and 500-year floodplain boundary
for Torne Brook.
There are no NYSDEC-regulated or federal jurisdictional wetlands preliminarily identified
on-site. However, the United States Geological Survey (USGS) has identified an area of
less than ten acres near the headwaters of Candle Brook and located east of the Baler
Building as a wetland (see Rgure 6). No NYSDEC-regulated wetlands occur within 9
miles downstream of the Site, though several occur within a 2-mile radius, either upstream
of the Site or on a different watershed. All wetlands on or adjacent to the Site will be
definitively delineated as one of the remedial design activities for the Site.
Groundwater is withdrawn from the area south and west of the Site for residential use.
Ten water supply wells, operated by the Spring Valley Water Supply Company and
serving a population of over 200,000, are located along the Ramapo River both upstream
and downstream of the Site. Four of these wells, SV-93, SV-94, SV-95, and SV-96 (see
Figure 2), are located within 1,500 feet of the landfill. The closest of these wells lies
approximately 500 feet west of the Site on the west bank of the Ramapo River. Torne
Brook Estate, a residential apartment complex of 25 units, has a water well, PW-1, 450
feet from the landfill. A 2-unrt apartment building maintains a water well, PW-2, about
1,200 feet from the landfill.
SITE HISTORY AND ENFORCEMENT ACTIVITIES
Site History
Prior to landfill operations in the 1950s and 1960s, portions of the Site were excavated as
a source of gravel.
In 1971, the Rockland County Department of Health granted a permit to the Town of
Ramapo for the operation of the sanitary landfill. At that time, the Site was owned by the
Ramapo Land Company and the contract-operator was the Torne Mountain Sand and
Gravel Co., Inc.
In 1976, a contract was awarded to Carmine Franco of Sorgine Construction Services of
New York, Inc., for operation and maintenance of the landfill. The contract was
terminated by the Town of Ramapo in 1979, when the Town began operating the landfill
directly. Municipal waste was accepted in the landfill until 1984. The Town of Ramapo
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3
continued to accept construction and demolition debris at the Site until 1989.
In September 1983, the Ramapo Landfill site was placed on the Superfund National
Priorities List.
The leachate collection and treatment system was constructed along the downgradient
edge of the landfill in 1984 and 1985. Surface water and groundwater were conducted
to a wastewater treatment pond in the Site's southwest corner. The pond's discharge
was initially to the Ramapo River after aeration and settling in the pond.
From April 1989 through May 1990, the first phase (Phase I) of Remedial Investigation
field work was carried out. From August to September 1990 the second phase (Phase
II) of field work was conducted.
As of November 1, 1990, leachate is no longer treated at the Site and discharged to the
Ramapo River. Leachate from the pond is being discharged to the Village of Suffern
Wastewater Treatment Plant, approximately 1.8 miles south of the Site, via a sewer line
of approximately 7,900 feet in length running along the shoulders of Torne Valley Road
and Route 59. The present contract with the Village of Suffern anticipates an average
daily flow of 80,000 gallons per day, for a maximum yearly flow of 29,200,000 gallons.
The contract runs for 5 years, and is renewable for an additional 5 years.
Enforcement Activities
On June 4,1980, the first of four Orders on Consent concerning the Ramapo Landfill was
entered into between the Town of Ramapo and the NYSDEC. The first order required the
Town of Ramapo, as Respondent, to: (a) determine the extent of leachate movement and
the feasibility of leachate collection; (b) construct a surface-water and groundwater-
diversion system; (c) construct a leachate-collection system; (d) construct a system
capable of transporting or treating the collected leachate; (e) phase out operation of the
landfill, and (f) meet other related requirements and schedule of compliance specified in
the Order.
On May 20, 1983, a Modified Order on Consent was signed, requiring the Town of
Ramapo to comply with a modified Schedule of Compliance, which required construction
of a leachate-collection system, maintenance of an interim surface-water diversion system,
construction of an Initial Treatment System with effluent monitoring, a subsurface
investigation program, the phase-out of the existing site for refuse disposal and
submission of a closure plan.
On February 8, 1985, an Order on Consent was signed which required that the Initial
Treatment System be completed by June 30,1985 and construction of a Final Treatment
System by October 31, 1986.
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On February 1, 1988, trie Town entered into its fourth and current (Title 3 1986
Environmental Quality Bond Act) Order on Consent (Index No. W3-0083-8707) with
NYSDEC. This Order requires that a remedial investigation and feasibility study (RI/FS)
and remedial program be developed and implemented for the Site, subject to approval
from NYSDEC.
HIGHLIGHTS OF COMMUNITY PARTICIPATION
On September 20,1989, the Town of Ramapo and NYSDEC conducted a public meeting
at the Town of Ramapo Town Hall, Ramapo, New York, to inform local officials and
interested citizens about the Superfund process, to review current and planned remedial
activities at the Site, and to respond to any questions from area residents and other
attendees.
The Rl report, FS report, and the Proposed Plan for the Site were released to the public
for comment on February 18,1992. These documents were made available to the public
in the administrative record file at the EPA Docket Room in Region II, New York and the
information repositories at NYSDEC, Albany, New York, the Finkelstein Public Library,
Spring Valley, New York, and the Suffern Free Public Library, Suffern, New York. The
public comment period on these documents was held from February 19,1992 to March
19, 1992.
During the public comment period, a public meeting was held in the Ramapo Town Hall,
Ramapo, New York on March 3, 1992, to present the RI/FS reports and the Proposed
Plan, answer questions, and accept both oral and written comments. At this meeting,
representatives from the EPA, NYSDEC, and the New York State Department of. Health
(NYSDOH) answered questions about problems at the Site and the remedial alternatives
under consideration. Responses to the comments received during the public comment
period are included in the Responsiveness Summary (see Appendix V).
SCOPE AND ROLE OF OPERABLE UNIT
This response action applies a comprehensive approach and, therefore, only one
operable unit is required to remediate the site.
Remedial action objectives are specific goals to protect human health and the
environment; they specify the contaminant(s) of concern, the exposure route(s),
receptor(s), and acceptable contaminant level(s) for each exposure route. These
objectives are based on available information and standards such as applicable or
relevant and appropriate requirements (ARARs) and risk-based levels established in the
risk assessment
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The following remedial action objectives were established: 1) prevent inhalation of vapors
from the landfill; 2) prevent human arid animal contact with contaminated soil from the
landfill surface; 3) prevent erosion of contaminated surface soil through surface-water
runoff; 4) minimize the infiltration of rainfall or snow melt into the landfill, thus reducing the
quantity of water percolating through the landfill materials and leaching out contaminants;
and 5) reduce the movement and toxicrty of the contaminated landfill leachate into
groundwater, and subsequent downgradient migration of contaminants.
NYSDEC is the lead agency for this project; EPA is the support agency.
SUMMARY OF SITE CHARACTERISTICS
Rl field work was carried out in two phases: Phase I from April 1989 through May 1990;
Phase II from August to September 1990. Media sampled during the Rl included surface
and subsurface soil, waste samples, groundwater, surface water, sediments, and air. All
Rl Phase I and II sampling locations, excluding air monitoring points, are depicted in
Figure 7.
Volatile compounds were detected in 3 waste sample locations, SPS-3, SPS-4, and SPS-5,
at concentrations ranging from 2 micrograms per kilogram (ug/kg) to 110 milligrams per
kilogram (mg/kg) (total xylenes at SPS-5). No volatile compounds were detected in any
of the surface soil samples including the background sample, SPS-9. Semi-volatile
compounds, including polycyclic aromatic hydrocarbons (PAHs), were detected in waste
samples and surface soil samples at concentrations ranging from 42 ug/kg to 16 mg/kg
(naphthalene at SPS-5). No semi-volatile compounds were detected in the background
sample. Antimony, barium, beryllium, cadmium, calcium, chromium, copper, lead,
selenium, and zinc were detected in surface soil and waste samples at concentrations
exceeding background by an order of magnitude. Acetone was detected in 4 subsurface
soil samples, MW-1-SB, MW-2-SB, MW-3-SB, and MW-5-SB, at concentrations ranging
from 13 to 28 ug/kg. Six semi-volatile compounds, acetone, and toluene were detected
in one monitoring well boring (MW-3-SB).
All five waste samples, (waste samples include landfill material and one paint sludge
sample), were analyzed for RCRA hazardous waste characteristics and extraction
procedure (EP) toxicrty parameters, for which there are regulatory levels. A comparison
between the EP Toxicity Criteria and levels detected from the samples is presented in
Table 1. No measurements exceeded the EP Toxicity Criteria. As part of RCRA testing,
the samples were also analyzed for the characteristics of ignitability, corrosivity, and
reactivity. Test results indicated that none of the waste samples were classified as a
RCRA characteristic waste.
During the installation of monitoring well MW-10, a leachate seep was observed. LSMW-
10 is a sample of the surface soil in this area. No volatiles were detected in this sample.
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Ten semi-volatiles were detected at concentrations up to 130 ug/kg (flouranthene). One
pesticide, gamma-chlordane, was detected at 4.5 ug/kg. Four inorganic compounds,
beryllium, cadmium, calcium, and mercury, were detected at concentrations greater than
an order of magnitude above background.
NYSDEC Water Quality Standards and Guidelines and/or EPA Primary Drinking Water
Standards are currently being contravened in groundwater monitoring wells installed in
the overburden, intermediate layer, and bedrock aquifers. Standards were exceeded for
arsenic, chromium, iron, lead, magnesium, manganese, mercury, sodium, benzene,
chlorobenzene, di-n-octyl phthalate, and total organic carbon. Maximum groundwater
concentrations of contaminants are compared with drinking water standards on Table 2.
A summary of the number of data which exceeded state and federal drinking water
standards is given in Table 3. No federal or state drinking water standards were
exceeded in samples taken from the nearby public or private water supply wells.
Phase I and Phase II surface water samples were collected on Torne Brook, on the
Ramapo River near the confluence of Torne Brook, a drainage swale on an adjacent
property, and from 2 leachate seeps emanating from the landfill. New York State surface
water standards were exceeded for vinyl chloride, antimony, arsenic, iron, manganese,
mercury, nickel, zinc, ammonia, sulfide, copper, and lead. The highest frequency of the
detections above the standards occurred at SW-1, near the confluence of Torne Brook
and the Ramapo River, when leachate from the treatment pond was still being discharged
to the Ramapo River. Maximum surface water concentrations of contaminants are
compared with surface water standards on Table 4. Table 5 includes a summary of the
number of data which exceeded state and federal surface water standards.
On July 12, 1991, NYSDEC sampled Torne Brook upgradient from the site, and at 3
locations on the Ramapo River. The 3 samples were collected roughly 150-feet upstream
of the former Outfall 001, at the confluence with the former outfall, and roughly 150 feet
downstream. The samples were analyzed for Target Analyte metals, cyanide, total
organic carbon and ammonia. Analytical results indicated that no standards were
exceeded for ammonia or any of the inorganic compounds previously noted as
contravening standards.
No volatile or pesticide compounds were detected in any of the sediment samples
collected in Tome Brook or the Ramapo River. Three semi-volatile compounds were
detected in a sediment sample collected in Tome Brook, SS-3, at concentrations below
NYSDEC sediment cleanup criteria. (See Table 6.) .Inorganic compounds detected in
sediments which exceeded background concentrations by at least an order of magnitude
included manganese at SS-1, calcium and thallium at SS-3, antimony and manganese at
SS-4, and calcium at SS-8.
An air monitoring study was conducted during the second phase of field activities to
determine methane quality and Target Compound List (TCL) organic gas emissions. Air
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monitoring locations are depicted in Rgure 8. The highest airborne concentration of a
volatile organic compound (VOC) detected on-site was recorded at a piezometer, P-2,
located in the northern lobe, west of the Baler Building. The results from the sample
collected indicated a total xylenes concentration of 7.7 milligrams per cubic meter, which
exceeded the NYSDEC Ambient Guideline Concentration (AGC) for this compound.
AGCs assume continuous exposure, however, and ordinarily are compared to annual
averages of air sample results. TCL organic emissions and AGCs are presented in Table
7. No other air sampling data exceeded NYSDEC AGCs.
SUMMARY OF SITE RISKS
A Baseline Risk Assessment was conducted to evaluate the potential risks to human
health and the environment associated with the Ramapo Landfill Site in its current state.
The Baseline Risk Assessment focused on contaminants in the soil, groundwater, and air
which are likely to pose significant risks to human health and the environment. A list of
the contaminants of potential concern in groundwater, soil, and air is found in Table 8.
The Baseline Risk Assessment identified several potential exposure pathways by which
the public may be exposed to contaminant releases at the Site under current and future
land-use conditions. Five exposure scenarios were evaluated under current and future
land-use conditions. These pathways included: ingestion of soil; dermal contact with soil;
inhalation of vapors from the landfill; ingestion of groundwater; and inhalation of vapors
during showering. These exposure pathways were evaluated separately for adults and
children and are listed in Table 9. Under the current land-use scenario, five potential
receptors were identified, namely, adult and child (ages 6-11) trespassers, adult and child
residents living downgradient and off-site, and employees (workers) at the landfill. Under
the future land-use scenario, three receptors were identified, namely adult and child (ages
0-6) residents living on-site, and workers. The reasonable maximum exposure scenario
was evaluated.
Under current EPA guidelines, the likelihood of carcinogenic (cancer causing) and
noncarcinogenic effects due to^exposurelo site chemicals are considered separately. It
was assumed that the toxjc effects of the site-related chemicals would be additive. Thus,
carcinogenic and noncarcinogenic risks associated with exposures to individual
compounds of concern were summed to indicate the potential risks associated with
mixtures of potential carcinogens and noncarcinogens, respectively.
Noncarcinogenic risks were assessed using a hazard index (HI) approach, based on a
comparison of expected contaminant intakes and safe levels of intake (Reference Doses).
Reference doses (RfDs) have been developed by EPA for indicating the potential for
adverse health effects. RfDs, which are expressed in units of mg/kg-day, are estimates
of daily exposure levels for humans which are thought to be safe over a lifetime (including
sensitive individuals). Estimated intakes of chemicals from environmental media (e.g.. the
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8
amount of a chemical ingested from contaminated drinking water) are compared with the
RfD to derive the hazard quotient for the contaminant in the particular medium. The
reference doses for the compounds of concern at the Ramapo Landfill site are presented
in Table 10. ,
The hazard index is obtained by adding the hazard quotients for all compounds across
all media. A hazard index greater than 1 indicates that the potential exists for
noncarcinogenic health effects to occur as a result of site-related exposures. The HI
provides a useful reference point for gauging the potential significance of multiple
contaminant exposures within a single medium or across media.
Under current land-use conditions, the total site HI exceeded one for workers and child
trespassers. Under future land-use conditions, the His exceeded 1 for all scenarios
evaluated. Primary chemical contributors to noncarcinogenic health risks were xylenes
(total) and chlorobenzene for inhalation of vapors from the landfill, and manganese and
arsenic for ingestion of groundwater. A summary of the noncarcinogenic risks associated
with the chemicals evaluated across various exposure pathways is found in Table 11.
Potential carcinogenic risks were evaluated using the cancer slope factors developed by
EPA for the contaminants of concern. Cancer slope factors (SFs) have been developed
by EPA's Carcinogenic Risk Assessment Verification Endeavor for estimating excess
lifetime cancer risks associated with exposure to potentially carcinogenic chemicals. SFs,
which are expressed in units of (mg/kg-day)"1, are multiplied by the estimated intake of
a potential carcinogen, in mg/kg-day, to generate an upper-bound estimate of the excess
lifetime cancer risk associated with exposure to the compound at that intake level. The
term "upper bound" reflects the conservative estimate of the risks calculated from the SF.
Use of this approach makes the underestimation of the risk highly unlikely. The SF for
the compounds of concern are presented in Table 12.
For known or suspected carcinogens, EPA considers excess upper bound individual
lifetime cancer risks of between 10"4 to 10"* to be acceptable. This level indicates that an
individual has not greater than a one in ten thousand to one in a million chance of
developing cancer as a result of site-related exposure to a carcinogen over a 70-year
period under specific exposure conditions at the Site. Under current land-use conditions,
the risk characterization showed that cancer risks for all receptors evaluated (i.e., adults,
children, and .workers) were less than or within the acceptable cancer risk range of 10"4
to 10* . Under future land-use conditions, cancer risks for children and workers were
within the NCP acceptable range. However, the sum of future cancer risks for all
exposure pathways assessed for adults (2 x 10"*) were marginally outside the range;
Arsenic and benzene were the chemicals responsible for the highest carcinogenic risks
from groundwater ingestion and inhalation of vapors, respectively. A summary of the
carcinogenic risks for the chemicals evaluated across various exposure pathways is found
on Table 13.
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The calculations were based on the contaminants detected in soils, on-site monitoring
wells, and air. It was assumed that in the future, on-site monitoring wells would be used
for residential purposes. Risk estimates were developed by taking into account various
conservative assumptions about the likelihood of a person being exposed to the various
contaminated media.
Uncertainties
The procedures and inputs used to assess risks in this evaluation, as in all such
assessments, are subject to a wide variety of uncertainties. In general, the main sources
of uncertainty include:
- environmental chemistry sampling and analysis
- environmental parameter measurement
- fate and transport modeling
- exposure parameter estimation
- toxicological data
Uncertainty in environmental sampling arises in part from the potentially uneven
distribution of chemicals in the media sampled. Consequently, there is significant
uncertainty as to the actual levels present. Environmental chemistry analysis error can
stem from several sources including the errors inherent in the analytical methods and
characteristics of the matrix being sampled.
Uncertainties in the exposure assessment are related to estimates of how often an
individual would actually come in contact with the chemicals of concern, the period of time
over which such exposure would occur, and in the models used to estimate the
concentrations of the chemicals of concern at the point of exposure.
Uncertainties in toxicological data occur in extrapolating both from animals to humans and
from high to low doses of exposure, as well as from the difficulties in assessing the
toxicity of a mixture of chemicals. These uncertainties are addressed by making
conservative assumptions concerning risk and exposure parameters throughout the
assessment. As a result, the Risk Assessment provides upper bound estimates of the
risks to populations near the Landfill, and is highly unlikely to underestimate actual risks
related to the Site.
More specific information concerning public health risks, including a quantitative
evaluation of the degree of risk associated with various exposure pathways, is presented
in the Rl Report.
Environmental Assessment
The environmental assessment evaluated exposure risks to aquatic life. Comparison of
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the results obtained from" sediment samples with NYSDEC sediment cleanup criteria
indicate that no contaminant concentrations found exceed the cleanup criteria. Therefore,
sediments are not expected to pose a risk to aquatic life. In reviewing the surface water
contaminant concentrations, aquatic surface water standards were exceeded for copper,
iron, lead, mercury, suifide, and zinc.
The ecological studies also indicated that there are no federally listed threatened or
endangered species identified at the Site. The landfill is in the historical range of a sub-
species of the Eastern Woodrat, Neotoma floridana magister. listed by NYSDEC as
endangered in New York State. However, because the species' habitat is within rock
outcrops or boulder fields, it is unlikely to occur on or in the immediate vicinity of the
landfill. No other NYSDEC rare, threatened, or endangered species or critical habitats are
known to occur within a 2-mile radius of the landfill, or within 9 miles downstream of the
landfill.
In summary, actual or threatened releases of hazardous substances from this Site, if not
addressed by the preferred alternative or one of the other active measures considered,
may present a current or potential threat to public health, welfare or the environment.
DESCRIPTION OF REMEDIAL ALTERNATIVES
CERCLA requires that each selected site remedy be protective of human health and the
environment, be cost-effective, comply with other statutory laws, and utilize permanent
solutions, alternative treatment technologies and resource recovery alternatives to the
maximum extent practicable. In addition, the statute includes a preference for the use of
treatment as a principal element for the reduction of toxicity, mobility, or volume of the
hazardous substances.
This Record of Decision evaluates in detail, 5 remedial alternatives for addressing the
contamination associated with the Ramapo Landfill site. The time to implement reflects
only the time required to construct or implement the remedy and does not include the
time required to design the remedy, negotiate with the responsible parties, or procure
contracts for design and construction.
These alternatives are:
Alternative 1: No Further Action with Monitoring
Capital Cost: $0
Operation and Maintenance (O & M) Cost: $345,700
Present Worth Cost: $3,260,000
Time to Implement: 3 months
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The Superfund program requires that the "no-action" alternative be considered as a
baseline for comparison with the other alternatives. However, since leachate collection
and off-site treatment of collected leachate and surface water are part of the ongoing
operations at the Site, the requirement for a "no-action" alternative is not relevant for this
Site. Therefore, a no further action alternative was considered.
The no further action alternative does not include any additional physical remedial
measures that address contamination at the Site. However, this alternative does include
maintaining the existing leachate collection system and continuing to send the collected
groundwater and surface water to the Suffern Wastewater Treatment Plant at a rate of
approximately 80 thousand gallons per day. It includes further long-term monitoring of
on-site monitoring wells and nearby residential wells for target compound list (TCL)
compounds, surface water in Torne Brook and the Ramapo River for TCL compounds,
and air for VOCs and landfill gases.
In addition, the no further action alternative would include the development and
implementation of a public awareness and education program to enhance the
community's knowledge of the conditions existing at the Site. This alternative would
require the involvement of local government, and several health departments and
environmental agencies.
Because this alternative would result in contaminants remaining on-site above health-
based levels, CERCLA requires that the Site be reviewed every five years. If justified by
the review, remedial actions may be implemented to remove or treat the wastes.
Alternative 2: Limited Action (with Option for Alternate Water Supply)
Capital Cost: $190,000 - $710,000
O & M Cost: $345,700
Present Worth Cost: $3,380,000 - $3,970,000
Time to Implement: 6 months
To date, results obtained from sampling of nearby private wells indicate that the wells are
not being adversely impacted by the landfill. Therefore, no provision for an alternate
water supply is warranted at this time. However, should future groundwater monitoring
data indicate that drinking water standards are being contravened in nearby wells, then
an alternate water supply may be deemed necessary. This alternative includes the
development, during the remedial design, of a contingency plan for the rapid
implementation of an alternate water supply, if shown to be needed. The contingency
plan would include the preliminary design for the alternate water supply. If drinking water
standards are significantly exceeded for site-related parameters in residential wells, or in
the same aquifer in the closest monitoring wells to the residental wells, and detected
concentations are confirmed by subsequent sampling, residents would immediately be
provided with bottled water and/or an acceptable point-of-use treatment system, as an
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interim measure until an alternate water supply could be constructed.
Posting and fencing of the landfill would be included in order to reduce the frequency of
trespassers on the landfill property. This alternative would also include deed restrictions
with respect to the future use of the Site, and the prohibition of on-site groundwater
extraction for potable use. The existing leachate collection system would be maintained,
and the collected groundwater and surface water would continue to be sent to the Suffern
Wastewater Treatment Plant. Similar to Alternative 1, this alternative would also include
long-term monitoring of groundwater, surface water in Torne Brook and the Ramapo
River, and air.
The higher end of the capital cost range ($710,000) and present-worth cost range
($3,970,000) for this alternative reflect the additional cost for the alternate water supply
which is considered an optional item.
As in Alternative 1, this alternative would include a public awareness and education
program.
Because this alternative would result in contaminants remaining on-site above health-
based levels, CERCLA requires that the Site be reviewed every five years. If justified by
the review, remedial actions may be implemented to remove or treat the wastes. .-
Alternative 3: Installation of Groundwater Extraction Wells
Capital Cost: $1,040,000 - $3,300,000
O & M Cost: $547,300 - $1,156,0001
Present Worth Cost: $6,206,000 - $14,210,000
Time to Implement: 6 months
Alternative 3 includes the installation of groundwater extraction wells to. supplement the
existing leachate collection system and restore contaminated groundwater aquifers.
Groundwater extraction wells would be installed in areas where the groundwater table
may be below the reach of the existing, leachate collection system. Portions of the
existing deep leachate collector would be plugged or grouted and new solid piping would
be laid in areas where the withdrawal wells are to be added, to avoid leakage of the
existing system. Collected leachate, groundwater and surface water would be sent to a
publicly owned treatment works (POTW) for off-site treatment. The off-site treatment
1The O&M costs for Alternatives 3, 4, and 5 assume continued treatment of
leachate and treatment of groundwater at the Suffem Wastewater Treatment plant.
The Town of Ramapo, however, is pursuing arrangements for treatment of leachate
and groundwater at the Rockland County Sewer District No. 1 publicly-owned
treatment works.
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facility could be the Suffern Wastewater Treatment Plant, which is currently receiving
wastewater discharged from the Site, or an alternate POTW. The selected POTW must
be in compliance with all federal and state permit requirements. In addition, the
wastewater discharged from the Site would have to meet all federal, state, local, and
pretreatment requirements for the specific POTW.
If deemed necessary by future groundwater monitoring data, an alternate water supply
would be provided for nearby users as discussed in Alternative 2. This alternative
includes the development, during Remedial Design, of a contingency plan for rapid
implementation of an alternate water supply, if shown to be needed. The contingency
plan would include the preliminary design for the alternate water supply, to the extent that
public water could be provided to nearby users within one year of determination of its
need based on monitoring results. As an interim measure, if drinking water standards are
significantly exceeded for site-related parameters in residential wells, or in the same
aquifer in the closest monitoring wells to the residents, and detected concentations are
confirmed by subsequent sampling, residents would immediately be provided with bottled
water and/or an acceptable point-of-use treatment system.
It is estimated that the proposed improvements to the leachate collection system would
increase the amount of groundwater collected and sent for treatment. Long-term
monitoring of groundwater and surface water would be included under this alternative.
Air monitoring for VOCs and landfill gases would be included, along with deed restrictions
with respect to the future use of the Site, and the prohibition of on-site groundwater
extraction for potable use. Posting and fencing of the landfill would be included in order
to reduce the frequency of trespassers on the landfill property.
The higher end of the capital cost range ($3,300,000) and present-worth cost range
($14,210,000) for this alternative reflect the additional costs for the alternate water supply
and groundwater pretreatment, which are optional items.
Because this alternative would result in contaminants remaining on-site above health-
based levels, CERCLA requires that the Site be reviewed every five years. If justified by
the review, remedial actions may be impjemented to remove or treat the wastes.
Alternative 4: Landfill Cap; Installation of Groundwater Extraction Wells
OPTION A:
Capital Cost: $26,170,000 - $29,310,000
O & M Cost: $319,600 - $622,600
Present Worth Cost: $29,190,000 - $35,760,000
Time to Implement: 2 years
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OPTION B:
Capital Cost: $21,870,000 -$25,010,000
O & M Cost: $319,600 - $622,600
Present Worth Cost: $24,890,000 -$30,880,000
Time to Implement: 2 years
Alternative 4 would involve the installation of a multi-media cap complying with New York
State Part 360 Solid Waste Regulations over the entire 60 acres of the landfill,
improvements to the existing leachate collection system, a surface water drainage and
diversion system, and relocating and/or raising of Torne Valley Road to allow for filling
rather than excavating the landfill side slopes in order to achieve stable slopes. With a
cap, there would be less infiltration into the landfill, and therefore, less potential for off-site
migration of contaminated groundwater. Option A costs reflect estimated costs for a
multi-media cap that meets all requirements of the New York State Part 360 Solid Waste
Regulations. Option B costs reflect estimated costs for a multi-media cap which is
identical to that in Option A, except that it would require a 12-inch thick fill layer above the
impermeable barrier as opposed to a 30-inch thick fill layer as required in Part 360. Both
fill layers would be covered by a 6-inch thick layer of topsoil. The reduced fill layer in
Option B would provide equivalent protection for the impermeable membrane, provided
that the impermeable membrane not be damaged by frost or root action. The selection
of the Option B cap would require approval from the NYSDEC for a variance of the Part
360 regulations.
The installation of groundwater extraction wells to supplement the existing leachate
collection system would be implemented as described in Alternative 3. However, with the
addition of a cap over the landfill, surface water would no longer have to be collected and
sent for treatment. Collected leachate and groundwater would be sent to a POTW for off-
site treatment. The off-site treatment facility could be the Suffem Wastewater Treatment
Plant, which is currently receiving wastewater discharged from the Site, or an alternate
POTW. The selected POTW must be in compliance with all federal and state permit
requirements. In addition, the wastewater discharged from the Site would have to meet
all federal, state, local, and POTW-specific pretreatment requirements.
Long-term monitoring of groundwater and surface water would be included under this
alternative. Air monitoring for VOCs and landfill gases would be included, and landfill
gases would be vented to the atmosphere or controlled, as needed. This alternative also
includes deed restrictions with respect to the future use of the Site, and the prohibition
of on-srte groundwater extraction for potable use. Posting and fencing of the landfill
would be included in order to reduce the frequency of trespassers on the landfill property.
Contaminated off-site soils resulting from leachate seeps would be removed and
consolidated within the capped area
If deemed necessary by future groundwater monitoring data, an alternate water supply
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would be provided for nearby users as discussed in Alternative 2. This alternative
includes the development, during the remedial design, of a contingency plan for the rapid
implementation of an alternate water supply, if shown to be needed. The contingency
plan would include the preliminary design for the alternate water supply. If drinking water
standards are significantly exceeded for site-related parameters in residential wells, or in
the same aquifer in the closest monitoring wells to the residental wells, and detected
concentations are confirmed by subsequent sampling, residents would immediately be
provided with bottled water and/or an acceptable point-of-use treatment system, as an
interim measure until an alternate water supply could be constructed.
The higher end of the capital cost range ($29,310,000 for Option A and $25,010,000 for
Option B) and present-worth cost range ($35,760,000 for Option A and $30,880,000 for
Option B) reflect additional costs for the optional items which include an alternate water
supply, groundwater pretreatment, and treatment of landfill gases.
Because this alternative would result in contaminants remaining on-site above health-
based levels, CERCLA requires that the Site be reviewed every five years. If justified by
the review, remedial actions may be implemented to remove or treat the wastes.
Alternative 5: Landfill Cap with Soil Cover on Side Slopes; Installation of
Groundwater Extraction Wells
Capital Cost: $18,390,000 - $21,640,000
O & M Cost: $319,800 - $678,600
Present Worth Cost: $21,410,000 - $28,050,000
Time to Implement: 2 years
Alternative 5 includes a landfill cap and improvements to the existing leachate collection
system. The landfill cap would be similar to the cap described in Alternative 4, Option B,
except for the absence of an impermeable membrane on the side slopes of the landfill.
While, the exclusion of the impermeable membrane from the cap on the side slopes
would result in an increase in the quantity of leachate generated, most of the leachate is
expected to be collected by the existing, leachate collection system and a proposed
groundwater extraction well network. The side slopes, where the existing slopes are
greater than 20 percent, are estimated to represent about 25 of the 60 acres. As New
York State Part 360 Solid Waste Regulations require an impermeable membrane under
the entire capped surface, this alternative would require approval from the NYSDEC for
a variance from New York State Part 360 regulations.. .This approval would be contingent
upon the ability of this alternative to collect leachate before it infiltrates into the
groundwater aquifers or migrates off-site. As in Alternative 4, Option B, this alternative
would also require a variance from New York State Part 360 regulations for the selection
of a fill layer of less than 30 inches in thickness overlying the impermeable barrier. Also
as in Alternative 4, contaminated off-site soils resulting from leachate seeps would be
removed and consolidated within the capped area. Also, landfill gases would be vented
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to the atmosphere or controlled, as needed.
The installation of groundwater extraction wells to supplement the existing leachate
collection system would be implemented as described in Alternative 3. However, with the
addition of a cap over the landfill, surface water would no longer have to be collected and
sent for treatment. Surface water runoff on the tops of the landfill lobes where the
impermeable membrane is present would be collected by a perimeter drain and diverted
so as to prevent infiltration from these areas. Collected leachate and groundwater, and
leachate seeps, if they occur, would be sent to a POTW for off-site treatment. The off-site
treatment facility could be the Suffern Wastewater Treatment Plant, which is currently
receiving wastewater discharged from the Site, or an alternate POTW. The selected
POTW must be in compliance with all federal and state permit requirements. In addition,
the wastewater discharged from the Site would have to meet all federal, state, local, and
POTW-specific pretreatment requirements.
With a cap, there would be less infiltration into the landfill, and therefore, less potential for
off-site migration of contaminated groundwater. Long-term monitoring of groundwater
and surface water as discussed in Alternative 2 would be included, along with deed
restrictions with respect-to future use of the Site, and the prohibition of on-site
groundwater extraction for potable use. Posting and fencing of the landfill would be
included in order to reduce the frequency of trespassers on the landfill property.
If deemed necessary by future groundwater monitoring data, an alternate water supply
would be provided for nearby users as discussed in Alternative 2. This alternative
includes the development, during the remedial design, of a contingency plan for the rapid
implementation of an alternate water supply, if shown to be needed. The contingency
plan would include the preliminary design for the alternate water supply. If drinking water
standards are significantly exceeded for site-related parameters in residential wells, or in
the same aquifer in the closest monitoring wells to the residental wells, and detected
concentations are confirmed by subsequent sampling, residents would immediately be
provided with bottled water and/or an acceptable point-of-use treatment system, as an
interim measure until an alternate water supply could be constructed.
The higher end of the capital cost range ($21,640,000) and present-worth cost range
($28,050,000) for this alternative reflect additional costs for the optional items which
include an alternate water supply, groundwater pretreatment, treatment of landfill gases.
Because this alternative would result in contaminants remaining on-site above health-
based levels, CERCLA requires that the Site be reviewed every five years. If justified by
the review, remedial actions may be implemented to remove or treat the wastes.
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SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
During the detailed evaluation of remedial alternatives, each alternative was assessed
utilizing nine evaluation criteria as set forth in the NCR and OSWER Directive 9355.3-01.
These criteria were developed to address the requirements of Section 121 of CERCLA to
ensure all important considerations are factored into remedy selection decisions.
The following "threshold" criteria are the most important, and must be satisfied by any
alternative in order to be eligible for selection:
1. Overall protection of human health and the environment addresses whether or not
a remedy provides adequate protection and describes how risks posed through
each exposure pathway (based on a reasonable maximum exposure scenario) are
eliminated, reduced, or controlled through treatment, engineering controls, or
institutional controls.
2. Compliance with ARARs addresses whether or not a remedy would meet all of the
applicable or relevant and appropriate requirements of federal and state
environmental statutes and requirements or provide grounds for invoking a waiver.
The following "primary balancing" criteria are used to make comparisons and to identify
the major trade-offs between alternatives:
3. Long-term effectiveness and permanence refers to the ability of a remedy to
maintain reliable protection of human health and the environment over time, once
cleanup goals have been met. It also addresses the magnitude and effectiveness
of the measures that may be required to manage the risk posed by treatment
residuals and/or untreated wastes.
4. Reduction of toxicity. mobility, or volume through treatment is the anticipated
performance of a remedial technology, with respect to these parameters, that a
remedy may employ.
5. Short-term effectiveness addresses the period of time needed to achieve protection
and any adverse impacts on human health and the environment that may be
posed during the construction and implementation periods until cleanup goals are
achieved.
6. ImDlementabil'rty is the technical and administrative feasibility of a remedy, including
the availability of materials and services needed.
7. Cost includes estimated capital and operation and maintenance costs, and the
present worth costs.
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The following "modifying" criteria are considered fully after the formal public comment
period on the Proposed Plan is complete:
8. State acceptance indicates whether, based on its review of the RI/FS and the
Proposed Plan, the State supports, opposes, and/or has identified any
reservations with the preferred alternative.
9. Community acceptance refers to the public's general response to the alternatives
described in the Proposed Plan and the RI/FS reports. Factors of community
acceptance to be discussed include support, reservation, and opposition by the
community.
A comparative analysis of the remedial alternatives based upon the evaluation criteria
noted above follows.
Overall Protection of Human Health and the Environment
The no further action alternative, Alternative 1, would be the least protective of human
health and the environment. Although it does provide for leachate collection and off-site
transport of collected leachate and surface water, it does not address any of the remedial
action objectives established for the Site. Alternative 2 would be more effective than
Alternative 1 in protecting human health and the environment, since fencing and posting
implemented under Alternative 2 would limit access to the Site by trespassers and
children and would provide for an alternate water supply to nearby users, if needed.
Alternative 3 would be more effective than Alternatives 1 and 2, since it would include
extraction and off-site treatment of contaminated groundwater. Alternatives 1, 2, and 3,
however, do not include any provision for a landfill cap and therefore do not reduce the
generation of leachate, prevent human and animal contact with contaminated soil from
the landfill surface, prevent erosion of contaminated surface soil, nor provide a means of
treating landfill gas emissions. Hence, Alternatives 1, 2, and 3 provide limited protection
of human health and the environment.
Alternative 4 is most protective of human health and the environment. Ingestion of
contaminated groundwater would be prevented by groundwater collection and off-site
treatment. The combination of the leachate collection system, off-site groundwater
extraction wells, and a multi-media cap would mitigate groundwater contamination. The
multi-media cap would reduce the amount of infiltration into the landfill, as well as the
water level within the landfill. This would lower the potential for downward migration of
contaminants through the bedrock aquifer and for off-site migration of contaminated.
groundwater. A cap in compliance with New York State Part 360 Solid Waste Regulations
would reduce infiltration to an overall 1.2 percent of precipitation. Alternative 4 Option B
would be equally protective as Alternative 4 Option A, provided that the synthetic material
selected for the impermeable membrane would not be damaged by frost or root action.
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Alternative 5 is more protective than Alternatives 1, 2, and 3, and may provide a
comparable degree of protection as Alternative 4. With the soil cap in Alternative 5, which
would not include a cap with an impermeable barrier over 25 of the 60 acres, infiltration
would be reduced to an overall 7 percent of precipitation. Although this infiltration rate
is about 6 times greater than the infiltration rate associated with Alternative 4, most of the
leachate generated by infiltration of precipitation would occur under the side slopes, and
would likely be collected. This is because of the relative proximity of the side slopes to
the existing leachate collection system and to the proposed groundwater extraction well
network.
With a properly engineered soil cover, Alternative 5 should be as effective as Alternative
4 in controlling landfill gas emissions, since both cap designs include a gas venting
system that can be retrofitted, if necessary, with gas treatment. Potential difficulties with
gas venting on the soil cap side slopes (e.g., from clogging) could be circumvented with
a more frequent placement of vent standpipes.
Direct contact with the waste would be equally mitigated by the caps proposed in
Alternatives 4 and 5.
Compliance with ARARs
A New York State Part 360 landfill cap is an action-specific ARAR for landfill closure2.
Alternatives 1, 2, and 3 would not meet this ARAR, since they do not include any
provisions for a landfill cap. Alternative 4 Option A would meet this ARAR, since it
includes a cap which would be constructed according to New York State Part 360
regulations. Alternative 4 Option B would meet this ARAR only with a variance for a
reduced amount of fill material covering the impermeable layer. The concept of a
variance is approvable, if an appropriate synthetic impermeable barrier were used and all
other requirements of New York State Part 360 Solid Waste Regulations for landfill closure
were met. Alternative 5 would only meet this ARAR with a variance for a reduced amount
of fill material covering the impermeable layer, and for the elimination of the impermeable
layer on the steep side slopes of the landfill.
Alternatives 4 would be the most effective in reducing groundwater contaminant
concentrations below maximum contaminant levels (MCLs) because of the lower
infiltration rate of precipitation associated with capping the entire landfill including the side
slopes. Alternative 5 may be nearly as effective as Alternative 4 in reducing groundwater
contaminant migration, if leachate and contaminated groundwater are effectively captured
by the improved leachate collection system and the proposed groundwater extraction
Installing a cap will reduce infiltration of precipitation through the landfill,
thereby reducing the generation of contaminated groundwater which
mioht exceed ARARs.
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wells. Alternative 3 would provide for improvements to the leachate collection system and
off-site treatment of leachate and extracted groundwater. However, Alternative 3 would
not include a Site cap, and, therefore, would not be in compliance with the New York
State landfill closure regulations. Alternatives 1 and 2 provide no measures for containing
wastes in the landfill, nor for addressing contaminated groundwater.
Under all alternatives, collected leachate and groundwater would be sent to a POTW for
off-site treatment. The selected POTW must be in compliance with all federal and state
permit requirements. In addition, the collected leachate and groundwater would have to
meet all federal, state, local, and pretreatment requirements for the specific POTW.
Long-Term Effectiveness and Permanence
Alternative 1 does not include any additional permanent measures for containing,
controlling, or eliminating any of the on-site contamination, or reducing the potential of
exposure to the contaminated landfill materials.
Alternatives 2 and 3 would provide limited protection including posting, fencing, deed
restrictions, and, if needed, an alternate water supply for nearby users. Alternative 3
would also provide for improvements to the existing leachate collection system. However,
these alternatives include no further measures to control or remediate Site contamination.
The closure caps proposed in Alternatives 4 and 5 represent a permanent measure that
could be maintained at regular intervals to ensure their structural integrity and
impermeability. Alternative 5 may require additional monitoring and maintenance to
ensure integrity of the cap, and to prevent leachate seeps.
Reduction in Toxicity. Mobility, or Volume Through Treatment
None of the alternatives proposed reduce the toxicity or volume of waste present in the
landfill.
All of the alternatives include off-site treatment of collected leachate and groundwater.
The installation of extraction wells, included with Alternatives 3 through 5, to supplement
the Site's existing leachate collection system would further reduce the toxicity, mobility,
and volume of contaminated groundwater than would Alternatives 1 and 2. The addition
of the proposed caps in Alternatives 4 and 5 would further reduce the toxicity, mobility,
and volume of contaminants by limiting or reducing infiltration of precipitation through the
landfill. The soil cap in Alternative 5 would not be as effective as the cap in Alternative
4, designed in compliance with New York State Part 360 Solid Waste Regulations, in
limiting generation of leachate.
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21
Short-Term Effectiveness
Since no construction is required to implement Alternative 1, the no further action
alternative, there would be no associated short-term impacts to the community, workers,
or the environment. However, while no increases in risks result in the short-term, no
protection against the principal Site threats would be achieved.
Alternative 2 would have the least short-term impact of the remaining alternatives, as it
involves the smallest construction effort on-site in potentially contaminated areas.
Alternative 3 would have the second lowest short-term impact, with limited construction
activities in potentially contaminated areas. However, these alternatives would provide
little protection against the principal Site threats.
Alternatives 4 and 5 contain multiple components, which increase the construction effort
as well as the time required for implementation. Both alternatives include caps, which
would involve clearing, grubbing, and re-grading of the landfill. Potential hazards to the
surrounding community, and environment may include airborne dust and particulate
emissions and an increase in noise levels. These impacts would be mitigated in part
through the employment of proper construction techniques and operational procedures.
Risks to on-site workers due to inhalation of contaminants adsorbed to fugitive dust would
be minimized through the use of personal protection equipment. Once the surface soils
are covered, the short-term impacts to the community, workers, and the environment
would no longer be present.
Implementability
Alternative 1, the no further action alternative, would be the easiest of the alternatives to
implement because it requires only additional monitoring of groundwater and surface
water.
Alternative 2 is the second easiest alternative to implement. The construction of water
supply lines and the installation of a fence would be easily implemented. Alternative 3 is
the third easiest alternative to implement. The installation of extraction wells and the
improvements to the leachate collection system, are not expected to be difficult to
implement.
Alternatives 4 and 5 involve capping the landfill, as well as improvements to the leachate
collection system. Construction methods for capping are well established, although some
technical problems, particularly for large construction projects such as this, may be
encountered. The potential for design and construction problems would be reduced
under Alternative 5, since the soil cap would not require the installation of a synthetic
impermeable barrier on steep side slopes. Stress situations such as bridging over
subsidence and friction between the synthetic impermeable barrier and other cover
components, especially on side slopes, may require special laboratory tests to ensure the
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22
design meets required performance standards. The synthetic liner specified in
Alternatives 4 and 5 requires a special handling during installation to ensure integrity.
All of the alternatives would involve some degree of institutional management. Alternative
1 would require administrative coordination of the groundwater monitoring program and
the 5-year Site status reviews, along with the development of the public education
program. Alternative 2 would require a similar effort for those activities, and also for
maintenance of the security fence and for installation of a water supply line to nearby
residents.
In addition to the above activities, administrative requirements for Alternative 3 would
include operation and maintenance of the improved leachate collection system and a
pretreatment facility, if needed. Collected leachate and surface water discharged from the
Site would have to be in compliance with the receiving POTW's pretreatment
requirements.
Administrative requirements for Alternatives 4 and 5 include the management of the
groundwater-monitoring program, improved leachate collection system, and alternate
water supply and pretreatment facility, if needed. In addition, the structural integrity and
impermeability of the closure cap must be maintained through a program of periodic
surveillance and necessary repairs. Because of the relatively large area of the landfill, this
effort and its associated cost may be fairly substantial.
Most services and materials required for implementation of all of these potential remedial
alternatives are readily available. Standard construction equipment and practices can be
employed for the fence installation of Alternatives 2 through 5 and the extensive
construction activities of Alternatives 4 and 5. Most of the materials and equipment
required for these alternatives may be obtained locally.
Because the work would be taking place on a Superfund site, all on-site personnel must
have approved health and safety training. Many companies are available to provide this
training to contractors. The engineering and design services required for implementation
of Alternatives 3 through 5 would be available from many vendors.
Cost
Present-worth cost estimates consider a 10% discount rate and a 30-year operational
period. The present-worth costs are as follows:
Alternative 1 $3,260,000
Alternative 2 $3,380,000 - $3,970,000
Alternative 3 $6,206,000 - $14,210,000
Alternative 4, Option A $29,190,000 - $35,760,000
Alternative 4, Option B $24,890,000 - $30,880,000
-------
23
Alternative 5 $21,410,000 - $28,050,000
The higher range for the present-worth cost in Alternative 2 reflects the additional costs
for the alternate water supply which is considered an optional item. The higher range of
capital costs and present-worth costs in Alternatives 3, 4, and 5 reflect additional costs
for the optional items which include an alternate water supply, groundwater pretreatment,
and treatment of landfill gases. Table 14 presents capital costs and annual O&M costs,
as well as present-worth cost estimates for all the alternatives.
State Acceptance
NYSDEC concurs with the selected remedy. NYSDEC will also Concur with the contingent
remedy, should the confirmatory studies determine that the contingent remedy is
appropriate. See Appendix IV.
Community Acceptance
The community's comments and concerns received during the public comment period
are identified and addressed in the Responsiveness Summary which is attached as
Appendix V to this document.
SELECTED REMEDY
Based upon consideration of the requirements of CERCLA, the detailed analysis of the
alternatives, and public comments, both NYSDEC and EPA have determined that
Alternative 5 is the appropriate remedy, with Alternative 4, Option B as a contingent
remedy for the Site.
While, the exclusion of the impermeable membrane from the landfill cap on the side
slopes, as discussed in Alternative 5, would result in an increase in the quantity of
leachate generated, most of the leachate is-expected to be collected by the existing
leachate collection system and a proposed groundwater extraction well network.
Therefore, the selection of Alternative 5 is contingent upon its ability to adequately collect
leachate before it infiltrates into the groundwater aquifers or migrates off-site.
Confirmatory studies will be performed during the remedial design phase to determine
whether Alternative 5 will attain a standard of performance equivalent to Alternative 4,
Option B in reducing migration of contaminated groundwater, preventing leachate
outbreaks, and restoring contaminated aquifers. Should the confirmatory studies indicate
that Alternative 5 would not meet these objectives, then Alternative 4, Option B would be
implemented at the Site, or in those Site areas where needed. Confirmatory studies may
include additional groundwater flow modelling and pump tests to determine the hydraulic
relationship between the upper and lower aquifers.
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24
The selected alternative, Alternative 5, is expected to achieve substantial risk reduction
through source control and a leachate and groundwater collection system.
The major components of the selected remedy are as follows:
Installation of a cap on the tops of the landfill using a multi-media system,
including layers of fill material, a gas-venting system and an impermeable
membrane. The landfill side slopes will be capped using a multi-media
system without an impermeable membrane, if confirmatory studies
demonstrate that this approach meets remedial action objectives. Should
the confirmatory studies indicate that the overall remedy's effectiveness
would be significantly reduced by not including an impermeable barrier in
the multi-media cap on the sideslopes, then an impermeable barrier would
be included in the cap on some or all of the side slopes of the landfill;
Regrading and compacting of the landfill mound to provide a stable
foundation for the placement of the cap prior to its construction;
Contaminated off-site soils resulting from leachate seeps would be removed
and consolidated within the capped area.
Installation of groundwater extraction wells to supplement the existing
leachate collection system;
Collection and diversion of leachate seeps to the leachate collection system
for off-site treatment;
Installation of a perimeter drain around the sections of the cap containing
the impermeable membrane to collect and divert surface water runoff;
If groundwater pretreatment is needed (pursuant to the requirements of the
POTW), construction of a pretreatment facility which would.be tied into the
existing leachate collection'and discharge system;
Performance of air monitoring prior to, during, and following construction at
the Site to ensure that air emissions resulting from the cap construction
meet applicable or relevant and appropriate requirements. Perimeter air
monitoring in the groundwater monitoring wells, piezometers, and additional
gas monitoring wells to be installed between the landfill and the Baler
Building will be performed. The gas monitoring wells will be monitored
quarterly for explosive gas concentrations.
Performance of air dispersion modeling to estimate ambient air
concentrations of contaminants. Landfill gas emissions will be controlled,
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25
if necessary.
Imposition of property deed restrictions by the appropriate State or local
authorities. The deed restrictions will include measures to prevent the
installation of drinking water wells at the site, and restrict activities which
could affect the integrity of the cap.
Performance of a maintenance and sampling program upon completion of
closure activities. The monitoring program will fulfill the requirements of 6
NYCRR Part 360 for post-closure landfill monitoring in addition to monitoring
parameters of concern found at the Site. Additional wells will be added
where needed to detect any movement of site-related contaminants toward
nearby private wells, including production wells of the Spring Valley Water
Company.
Development of a contingency plan for rapid implementation of measures
to protect nearby residents and users of groundwater if those measures are
determined to be necessary.
Samples will be collected on a quarterly basis for site-related parameters
from nearby residential wells and from new and selected existing monitoring
wells. If increases are noted through this monitoring program at or
immediately upgradient of the residences, the State and EPA will make a
determination as to the need for appropriate action (i.e., extension of a
public water line) to remedy the situation.
Development and implementation of a dust control plan. The plan will
contain all possible sources of fugitive dust emissions including intrusive
field activities such as excavation or regrading of waste. Normal dust
suppression techniques for handling of soils and road materials will be
addressed in the plan. The plan should also include how each of these
potential dust sources will be controlled by addressing the control methods
that will be conducted.
•*^
Spring Valley Water Company (SVWC) production well Nos. 93,94,95, and
96 will be monitored quarterly for the site parameter list, if site parameters
are not already being monitored by SVWC. After one year, if the monitoring
program does not show trends suggesting an impact from site-related
contaminants, the monitoring schedule for these wells can be adjusted to
conform with the minimum monitoring requirements specified under Chapter
10, Subpart 5-1 of the New York State Sanitary Code.
Delineation and evaluation of any wetlands on or adjacent to the Site or
impacted by the Site consistent with the Federal Manual for Identifying and
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26
Delineating Jurisdictional Wetlands (1989):
Performance of a Stage 1A cultural resources survey, as early as possible
during Remedial Design, on-site and in off-site areas where there is a
potential impact to cultural resources.
The purpose of this response action is to reduce the present risk to human health and
the environment due to contaminants leaching from the landfill mound. The capping of
the landfill will minimize the infiltration of rainfall and snowmelt into the landfill, thereby
reducing the potential for contaminants leaching from the landfill and negatively impacting
the wetlands habitat and groundwater quality. Capping will prevent direct contact
exposure to contaminated soils, and as such will result in risks which are less than EPA's
target levels of 10"6 and 1 for carcinogenic risks and the noncarcinogenic hazard index,
respectively.
Pumping and treating the groundwater will contain the groundwater contamination within
the Site boundary and will ensure that groundwater beyond the Site boundary meets
applicable or relevant and appropriate state and federal standards for groundwater. The
extracted leachate and groundwater will be discharged to a POTW for off-site treatment.
The response action also reduces the movement and toxictty of the contaminated landfill
leachate into groundwater, and subsequent downgradient migration of contaminants.
STATUTORY DETERMINATIONS
Under its legal authorities, EPA's primary responsibilities at Superfund sites is to
undertake remedial actions that achieve protection of human health and the environment.
In addition, Section 121 of CERCLA establishes several other statutory requirements and
preferences. These specify that when complete, the selected remedial action for this site
must comply with applicable or relevant and appropriate environmental standards
established under federal and state environmental laws unless a statutory waiver is
justified. The selected remedy also must be cost-effective and utilize permanent solutions
and alternative treatment technologies or resource recovery technologies to the maximum
extent practicable.' Finally, the statute includes a preference for remedies that employ
treatment that permanently and significantly reduce the volume, toxicrty, or mobility of
hazardous wastes, as available. The following sections discuss how the selected remedy
meets these statutory requirements. The contingent remedy will also meet these
requirements.
Protection of Human Health and the Environment
Alternative 5 and Alternative 4, Option B are fully responsive to this criterion and to the
-------
27.
identified remedial response objectives. Capping the landfill protects human health and
the environment by reducing the mobility of contaminated materials, in that the leaching
of contaminants into the aquifers will be significantly reduced. In addition, capping the
landfill will eliminate threats posed to adults, children, trespassers, and wildlife who come
in contact with the Site. The extraction and treatment of contaminants in groundwater will
prevent the off-site groundwater from being contaminated above drinking water standards,
thereby ensuring that the community continues to have a potable supply of drinking
water.
Compliance with ARARs
The selected remedy would require approval from the NYSDEC for a variance from New
York State Part 360 Solid Waste Regulations for the elimination of the impermeable layer
on the side slopes of the landfill. NYSDEC approval of this variance is contingent upon
the results of the confirmatory studies to determine the effectiveness of Alternative 5.
Both cap designs in the selected and contingent remedies specify a 12-inch fill layer
overlying the impermeable barrier. The selection of a 12-inch fill layer would require
approval from NYSDEC for a variance from New York State Part 360 Solid Waste
Regulations in order to meet frost protection requirements. NYSDEC considers this
variance to be approvable at this site, providing that a synthetic membrane meeting
appropriate performance standards is used as an impermeable barrier.
Attainment of chemical-specific ARARs for groundwater will be hastened due to reduced
leaching following construction of the cap and the extraction and treatment of leachate
and groundwater. The source of surface water contamination (leachate seeps) will be
eliminated. Action- and location-specific ARARs will be complied with during
implementation.
Action-specific ARARs:
New York State Solid Waste Management Facilities 6 NYCRR Part 360
National Emissions Standards for Hazardous Air Pollutants (NESHAPs)
6 NYCRR Part 257 Air Quality Standards
6 NYCRR Part 212 Air Emission Standards
6 NYCRR Part 373 Fugitive Dusts
40 CFR 50 Air Quality Standards
SPDES - Discharge
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28
Resource Conservation and Recovery Act (RCRA)
Chemical-specific ARARs:
SDWAMCLs
6 NYCRR Part 703.5 Groundwater Quality Regulations
6 NYCRR Part 702 Surface Water Standards
10 NYCRR Part 5 State Sanitary Code
Location-specific ARARs:
Clean Water Act Section 404, 33 USC 1344
Fish and Wildlife Coordination Act, 16 USC 661
National Historic Preservation Act, 16 USC 470
New York State Freshwater Wetlands Law ECL, Article 24, 71 in Title 23
New York State Freshwater Wetlands Permit Requirements and
Classification, 6 NYCRR 663 and 664
New York State Endangered and Threatened Species of Fish and Wildlife
Requirements, 6 NYCRR 182
Other Criteria, Advisories, or Guidance To Be Considered:
Executive Order 11990 (Protection of Wetlands)
Executive Order 11988 (Roodplain Management)
EPA Statement of Policy on Roodplains and Wetlands Assessments for
CERCLA Actions
New York Guidelines for Soil Erosion and Sediment Control
New York State Sediment Criteria, December 1989
New York State Air Cleanup Criteria, January 1990
-------
29
SDWA Proposed Maximum Contaminant Levels (PMCLs) and
Maximum Contaminant Level Goals (MCLGs)
Sole Source Aquifer (SSA) Petition under review for the Ramapo River
Watershed
NYSDEC Technical and Operational Guidance Series 1.1.1, November 1991
Cost-Effectiveness
The selected remedy and the contingent remedy provide overall effectiveness proportional
to their costs. The total capital and present worth cost ranges for the selected remedy
are estimated to be $18,960,000 - $22,210,000, and $19,890,000 - $26,423,000,
respectively. For the contingent remedy, the corresponding cost ranges are $22,440,000
- $25,580,000 and $23,230,000 - $29,230,000, respectively.
Utilization of Permanent Solutions and Alternative Treatment Technologies to the
Maximum Extent Practicable
The selected remedy and contingent remedy utilize permanent solutions and alternative
treatment technologies to the maximum extent practicable. The selected remedy and the
contingent remedy represent the best balance of trade-offs among the alternatives with
respect to the evaluation criteria.
The extraction and subsequent treatment of groundwater will permanently and significantly
reduce the toxicity, mobility, and volume of contaminants in the groundwater.
Confirmatory studies will be performed to demonstrate that the selected remedy meets
all remedial action objectives. If the confirmatory studies indicate that the selected
remedy is not effective in meeting remedial action objectives, then the contingency
remedy will be implemented, where needed.
The selected remedy and contingent remedy will require construction of a landfill cap.
No technological problems should arise since the technologies and materials needed for
capping the landfill are readily available. With the construction of the landfill cap, the
direct contact risk to the landfill surface will be eliminated.
Preference for Treatment as a Principal Element
The statutory preference for remedies that employ treatment as a principal element cannot
be satisfied for the landfill itself, since treatment of the landfill material is not practicable.
The size of the landfill and the fact that there are no identified on-site hot spots that
represent the major sources of contamination preclude a remedy in which contaminants
could be excavated and treated effectively. However, the selected remedy and the
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30
contingent remedy call for the treatment of contaminated groundwater at the Site and,
hence, satisfy the preference for treatment for this portion of the remedy.
DOCUMENTATION OF SIGNIFICANT CHANGES
There are no significant changes from the preferred alternative presented in the Proposed
Plan, other than a modification of the capital, O&M, and present worth costs associated
with Alternatives 3-5.
In the Proposed Plan, the O&M costs associated with Alternatives 1 and 2 reflected
continued treatment of the leachate from the landfill at the Suffern Wastewater Treatment
plant, while Alternatives 3 - 5 reflected O&M costs associated with treatment of the
leachate and groundwater at an alternative facility. The costs in ROD, however, reflect
treatment of the leachate and groundwater for all of the alternatives at the Suffern
Wastewater Treatment plant. The Town of Ramapo, however, is pursuing arrangements
for treatment at the Rockland County Sewer District No. 1 POTW.
-------
APPENDIX
FIGURES
-------
Figures
Figure 1 - Site Location
Figure 2 - Site Plan
Figure 3 - Thickness of Fill
Figure 4 - Leachate Collection System
Figure 5 - Floodplain Boundary Map
Figure 6 - Wetlands in Landfill Area
Figure 7 - Environmental Sampling Locations
Figure 8 - Air Monitoring Locations
-------
i ( /; : ,'/ -•' o
, -•> i , ( -:aef a
.—^ ) - /* V*
\_-' \ S^ -X/
-<^- a ^,cc/ / /
• / r- - (.
vsr.jvvxx.-r, v. ;;
'• "si-' • ' • ^' j \-^.-- vv
-^> .•C' ^' , < ,^^^-r^.' .
USGS 7.5 MINUTE SERIES
RAMSEY AND SLOATSBURG
QUADRANGLES (1955)
SITE LOCATION
-------
~SOO«x CONTOUR LIMES & ELEVATION] IN FIET
• PW MIVATr WELL
• IV MHlfO V
-------
LEGEND
FILL ISOPACH (10 FEET)
LANDFILLED AREA
BORROW AREA
(AREA BELOW 1955 SURFACE!
FILL THICKNESS BASED UPON
THE DIFFERENCE BETWEEN THE
PRE-LANDFILL SURFACE (USGS.19331
AND THE PRESENT SURFACE. TEN 1101
••V' FILLING IS ASSUMED. ACTUAL
. — -i^' . EXCAVATION WAS IRREGULAR AND
„:===•=•* = == ~<-s RANGED FROM 3 TO 20 FEET.
^f»f • X- 0 ISO JOO FEET
THICKNESS OF FILL
URS
CONSULTANTS. IMC
FIGURE u3
-------
FORCE MAIN TO SUFFERN
WASTJWATER TREATMENT PLANT
LEACHATE HOLDING
PONO(FORMER
LEACHATE
TREATMENT
PONO)
PERFORATED UNOERORAIM
SOLID UNDERDRAW
O MANHOLE
— FLOW
Q • CAGE STRUCTURE
130 300 FEET
EXISTING LEACHATE COLLECTION
SYSTEM
URS
FIGURE
-------
SPECIAL FLOOD HAZARD AREAS • INUNDATED .
BY 100-YEAR" FLOOD
ZONE A NO BASE FLOOD ELEVATIONS DETERMINED
ZONE X AREAS DETERMINED TO BE OUTSIDE
500-YEAR FLOOD PLAIN
FLOOD BOUNDARY MAP
-------
NYSOEC PROTECTED
WETLAND
USGS IDENTIFIED
WETLAND
'•'' /• • .' -v.- ••
iK. I ' ':"* -';«
w. \J ninti Op«n Cimp •-'
=1*7 IBSAh ~fr.
IN LANDFILL AREA ( 2 MILE RADIUS 1
-------
SAMPLNG POINTS
MW MONITORING WELL INSTALLED 8Y URS CONSULTANTS
P PIEZOMETER
SG STREAM GAUGE
SW SURFACE WATER AND STREAM SEDIMENT SAMPLE
SPS WASTE SAMPLE
A SPS SURFACE SOIL SAMPLE
0 SW-LS LEACHATE SEEP SAMPLE
GT GRAIN SIZE
7-0/S \\ io-0/S
NOTE
SW-SIS COINCIDENT
WITH SW-2 TAKEN 100
NORTHEAST OF
SVP-1
O SWE SURFACE WATER ELEVATION
EASEMENT LINE
LEACHATE COLLECTION SYSTEM
SVP STREAM VELOCITY PROFILE
0 PW PRIVATE WELL
3 SV RAMAPO VALLEY WELL FIELD WELL
D GOT TAP WATER SAMPLE
3
ENVIRONMENTAL
SAMPLING LOCATIONS
-------
PTOB - PSR-3/PSR-30 (PS-3)
I25O
-I/POINTSOU»CE.PSH'2(PS.2I
ICO«+,GS-3
78Q
7205- SAMPLE POINT LOCATION
WHERE HNU >Ippm
83 - SAMPLE POINT LOCATION NUMBERS
FOR THE FOLLOWING SYMBOLS:
- 24" METHANE > 50%
- AMBIENT METHANE
O - HjS pippin
• • H25 >lppm/24" METHANE > 50 %
O ' PIEZOMETER
^PSH-IIPS.I)
BACKGROUND
METHANE EMISSION SAMPLE LOCATION
PERIMETER MONITORING LOCATION
\S/S?/""">^ S \ 4^ HOT SPOT SAMPLE LOCATIONS
.;:==rC^ ^,S=»-CC*=*=-K- ^ POIMT SOljHCE SAMPLE LOCATIONS
^f>* ""*<•.,_ • 0 ISO JOC FEET
. AS PER TESTING CN SITE (_IIJB^H
AIR MONITORING LOCATIONS
URS
FIGURE 8
-------
APPENDIX II
TABLES
-------
Tables
Table 1 - Comparison Between Analytical Results for Wastes and EP Toxicity Limits
Table 2 - Comparison of Maximum Groundwater Concentrations to ARARs
Table 3 - Locations of Groundwater Data Exceeding ARARs
Table 4 - Comparison of Maximum Surface Water Concentrations to ARARs
Table 5 - Locations of Surface Water Data Exceeding ARARs
Table 6 - Sediment Cleanup Criteria
Table 7 - Phase II VOA Analytical Summary
Table 8 - Chemicals of Potential Concern
Table 9 - Potential Exposure Pathways
Table 10 - Toxicity Values: Potential Noncarcinogenic Effects
Table 11 - Summary of Noncancer Risks
Table 12 - Toxicity Values: Potential Carcinogenic Effects
Table 13 - Summary of Cancer Risks
Table 14 - Summary of Costs for Remedial Alternatives
-------
TABLE 1
COMPARISON BETWEEN ANALYTICAL RESULTS FOR
WASTES AND EP TOXICITY LIMITS
Parameter
Arsenic
Barium
Cadmium
Chromium
Lead
Mercury
Selenium
Silver
Endrin
Lindane
Methoxychlor
Toxaphene
2,4-D
2,4,5-TP
SPS-1
0.322
0.640
SPS-2
0.417
0.13
0.01
SPS-3
0.433
SPS-4
1.170
0.3
SPS-5
1.900
0.009
0.0461
0.320
EP Toxicicy
Limic
5.0
100.0
1.0
5.0
5.0
0.2
1.0
5.0
0.02 ;
0.4
10.0
0.5
10.0
1.0
Note: All concencracions are in mg/1 (ppm).
-------
TABLE 2
COMPARISON OF MAXIMUM DOWNGRADIENT GROUNDWATER DATA TO ARARS
Parameter
Carbon Disulfide
Benzene
1 , 1 -Dichloroethane
Chloromethane
1 ,2-Dichloroethane
4-methy1-2-pentanone
Dichlorodifluoromethane
Trichloroethane
Acetone
Toluene
Tetrachloroethene
cis-1 ,2-Dichloroethene
Styrene
Chlorobenzene
p-lsopropyltoluene
Isopropylbenzene
1 ,3,4-Trimethyl benzene
1 ,2.4-Trimethvlbenzene
1.3,5 trimethylbenzene
m&p-Xvtene
o-Xyiene
Propyl benzene
tert-butyl benzene
1-2, Dichloro benzene
Diethytphthalate
1 ,4-Dichlorobenzene
Butyl benzylphthalate
Bis(2-ethylhexvl) phthalate
Oi-n-octylphthalate
qamma-BHC
Naphthalene
pyrene
deHa-BHC
Aluminum
Arsenic
Barium
Cadmium
Calcium
Overburden
Max/Cone.
(ppb)
2 '
21
0.7
0.6
1
1.2
1.1
,f
3
19.000
26.1
441
132,000
Overburden
Location of
Max. Cone.
, - -GVV-8,
GW-6
GW-6
GDT-1
GW-8
GW-€
GW-8
GW-1/GW-2
GW-2
GW-8
GW-8
GW-2
Inter-
mediate
Max. Cone.
(PPb)
,. 2.9. - -
3
3
0.2
0.2
28
1
0.6
0.3
0.6
16
1.7
3.7
1.9
1.4
1.3
0.7
0.8
1.5
1.2
5
30
4.2
3
1.9
5,160
11
559
4.9
113.000
Inter-
mediate
Location of
Max. Cone.
GW-8
GW-4
GW-8
GW-4
GW-6
GW-2
GW-8
GW-6
GW-1
GW-6
GW-B
GW-8
GW-8
GW-4
GW-6
GW-8
GW-6
GW-8
GW-8
GW-8
GW-8
GW-4
GW-7
GW-8
GW-9 split
GW-4
GW-4
GW-8
GW-8
GW-4
GW-4
Bedrock
Max.
Cone.
(PPb)
2
3 ,,
5
0.1
3
0.2
35
0.3
0.9
2
1.2
1.0
1.9
0.5
0.9
3
2
27
130 .
0.11
0.8
2700
4.9
117
219,000
Bedrock
Location
Max. Cone.
GW-4
GW-8
GW-4
GW-4
GW-1
GW-4
GW-8
GW-6
GW-8
GW-9
GW-9
GW-9
GW-9
GW-9
GW-9
GW-4
GW-8
GW-7
ow-e
GW-9 split
GW-8
GW-10
GW-9 split
GW-9 spirt
GW-8
ARAR
Value3
(Ppb)
^
NO
5
5b
5
^
.5"
5
50C
5b
5
5°
5
5
5"
5b-
5b
5b
5b
5
5
56
5b
4.7+
50
4.7*
50
50
50
NO
10
50
NO
25
1.000
10
—
-------
TABLE 2 (Continued)
Parameter
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Nickel
Potassium •
Sodium
Vanadium
Zinc
BOD
COD
Total Kieldahl Nitrogen
Ammonia-N
TKN
Alkalinity
Acidity
NO3/NO2-N
Total Phosphorus
Oil & Grease
TOC
TSS
TDS
PH
Spec. Conductance
Sulfate
Overburden
Max. Cone.
(ppb)
1,290
42.3
78.3
229,000
34.1
31,500
31,200
0.63
331
31,200
102,000
51.6
107
20
140
59.6
61
1,048 '
563
0.62
0.79
77.*
5,000
1.500
80.9
Overburden
Location of
Max. Cone.
GW-3
GW-2
GW-1
GW-8
GW-2
GW-6
GW-10
GW-6
GW-3
GW-7
GW-8
GW-1
GW-2
GW-7
GW-8
GW-8
GW-8
GW-8
GW-8
GW-9
GW-2
GW-3
GW-1
GW-8
GW-2
Inter-
mediate
Max. Cone.
(Ppb)
280
36.2
20.9
30,500
5.3
71,400
4,500
2.3
162
196.000
643,000
19.5
23.9
25
94.4
28.3
772
622
0.44
3
74.8
560
1.200
62.8
Inter-
mediate
Location of
Max. Cone.
GW-1
GW-8
GW-4
GW-8
GW-4
GW-8
GW-*
GW-6
GW-1
GW-8
GW-S
GW-8
GW-8
GW-4
GW-8
GW-8
GW-8
GW-8
GW-2
GW-1
GW-8
GW-1
GW-8
GW-1
Bedrock
Max.
Cone.
(ppb)
39.7
19.5
39.3
22.700
11.4
51,100
12.400
2
35.3
19,100
154,000
6.1
53.7
27
97
26.4
25.8
444
380
0.62
0.34
6.7
95,1
60
800
8.87
1500
39.9
Bedrock
Location
Max. Cone.
GW-1
GW-3
GW-8
GW-9 split
GW-4
GW-8
GW-3
GW-8
GW-9 split
GW-9 split
GW-9 Split
GW-10
GW-8
GW-9
GW-9
GW-9
GW-9
GW-8
GW-8
GW-7
GW-1
GW-1
GW-3
GW-4
GW8
GW-2
GW-8
GW-8
ARAR
Value8
(ppb)
50
200
300
15'
35,000
300
2
^
^
20,000
^
300
__.
_^
—
_ _
10e
_„
0.1
_
_
250
a - The values were obtained from New York State DEC Water Quality Standards and Guidelines dated September 1990.
b - The values were obtained from Chapter I - New York State Sanitary Code, Subpart 5-1, Principle Organic Contaminants.
c - The values were obtained from Chapter I - New York State Sanitary Code, Subpart 5-1, Unspecified Organic Contaminants.
d - The values were obtained from USEPA Drinking Water Standards
e - This values is for NO3-N only. Analytical results are given as NO-j/NOj-N
f - USEPA proposed action level
+ - This value applies to the sum of 1,4 and 1,2-dichlorobenzene
NA - This well could not be sampled due to insufficient sample volume.
ND - Not detected
Shaded values exceed ARARs
-------
Parameter
Arsenic
Chromium
Iron
Lead
Manganese
Sodium
TOC
Benzene
Benzene
Chlorobenzene
alpha-BHC
delta-BHC
Chromium
Iron
Magnesium
Manganese
Mercury
TOC
TABLE 3
LOCATIONS OF GROUNDWATER DATA EXCEEDING ARARS
OVERBURDEN
Location
GW-8
GW-1, GW-2, GW-3, GW-4, GW-5
GW-1, GW-2, GW-3, GW-4, GW-5, GW-6, GW-7, GW-8, GW-9 split
GW-2
GW-1 through GW-8, GW-10
GW-1, GW-3, GW-4, GW-6. GW-7, GW-8
GW-1 through GW-10, not analyzed in GW-5
GW-5, GW-8, GW-4
INTERMEDIATE
GW-1, GW-4, GW-6, GW-7, GW-8. GW.9
GW-8
GW-5
GW-4
GW-1, GW-4, GW-5, GW-7, GW-8
GW-1 through GW-8
GW-4, GW-8
GW-1, GW-4, GW-7. GW-8. GW-9
GW-6
GW-1, GW-4, GW-5, GW-7, GW-8
1,1-Dichloroethane
Benzene
Di-n-octyl phthalate
gamma-BHC
Iron
Magnesium
Manganese
Mercury
Sodium
TOC
BEDROCK
GW-4
GW-4. GW-8, GW-9 -
GW-8
GW-7
All wells
GW-8 "• '
GW-3, GW-4, GW-8, GW-9, GW-9 spirt
GW-8
GW-3, GW-4, GW-7, GW-8. GW-9
GW-3. GW-4, GW-5. GW-8. GW-9. GW-10
-------
TABLE 4
COMPARISON OF MAXIMUM SURFACE WATER CONCENTRATIONS TO ARABS
Parameter
Vinyl cnloride
Benzene
Toluene
Aluminum
Antimony
Arsenic
Barium
Calcium
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Nickel
Potassium
Sodium
Thallium
Vanadium
Zinc
Total Cyanide
Total phenols
Ammonia-Nitrogen
TOC
NO3-N
NO2-N
TDS
Sulfate
SulfWe
pHMIn.
pH Max
.Upstream Max. Cone.
Detected (ug/l)
1.9
120
14
4.S70
163
1.8
1.100
44.5
0.36
432
2.740
5.3
35.7
7
110
1.640
32.000
57.100
1.400
6.93
7.52
Downstream Max
Cone. Detected (ug/l)
0.7
0.08
0.2
995
37.8
1.9
83.0
110.000
6.4
2.630
^8
33.100
1.120
1.2
25.2
42.100
109,000
5.4
54.9
33
18
21.900
21.300
6.960
2.380
873.000
74.600
2.000
6.69
7.41
Downstream
Location of Max
Cone.
SW-6
SW-6
SW-7
SW-8
SW-1
SW-1
SW-1
SW-1
SW-1
SW-1
SW-8
SW-1
SW-1
SW-1
SW-1
SW-1
SW-1
.
SW-8
SW-3
SW-1
SW-1
SW-1
SW-1
SW-1
SW-1
SW-1
SW-1
SW-1
SW-1
SW-3
Human ARAR/
Source
(ug/l)
0.3 A
0.7 B
5A
3 A
0.0022 B
1.000 MB
200 A
300 A
50A&B
35.000 A
300A
. 0.14 B
1.3 E-7 B
4 A
300 A
100 A
1 A
2.000 A
100 A
10.000 A&B
100 A
500.000 A
250.000 A
50 A
6.5 A
8.5 A
Aquatic ARAR/
Source (ug/l)
6A
1,600 B
(*)A
300A
C)A
0.0126
(*)A
8A
14A
30 A
5.2 B
C)A
2 A
Sources:
A - NYSDEC TOGS 1.1.1 dated September 1990
B - Clean Water Act
Notes:
• - ARAR value must be calculated see Table 4a.
-------
Table 4a
Calculated Surface Water ARARs
Parameter
Hafdnen
pH
Temp
Ammonia
Copper
Lead
Nickel
Unlta
ppm
SU
deg C
ppm
ppb
ppb
ppb
Cone.
477
7.28
13.0
21.9
6.4
1.4
25.2
SW-1
Calculated
ARAB
4
44.9 ,
23.3
313
Cone.
12.4
6.93
11.0
0.11
NO
ND
NO
SW-2
Calculated
ARAR
5
SV
Cone.
13.8
7.28
11.0
0.10
ND
NO
ND
W
Calculate
dARAR
4
S
Cone.
S.67
7.52
21
NA
ND
1.8
ND
l/V-5
Calculated
ARAR
0.08
SV
Cone.
6.06
6.86
21
NA
3.1
1.6
ND
M
Calculated
ARAR
1.1
0.09
SV
Cone.
6.03
7.11
21
NA
ND
1.7
ND
V-7 .•
Calculated
ARAR
0.09
SVt
Cone.
. 7.60
7.03
21
NA
ND
2.8
ND
1-6
Calculated
ARAR
0.12
-------
TABLES
LOCATIONS OF SURFACE WATER DATA EXCEEDING ARARS
Parameter Location
Vinyl chloride SW-5, SW-6
Antimony SW-1
Arsenic SW-1
Iron SW-1, SW-8
Manganese SW-1
Mercury SW-1, SW-5, SW-6. SW-7, SW-8
Nickel SW-1
Thallium SW-2
Zinc SW-2, SW-3, SW-4
Ammonia SW-1
TOG SW-1, SW-5. SW-6, SW-7, SW-8
NO2-N SW-1
TDS SW-1
Sulfide SW-1, SW-2
Copper SW-6
Lead SW-5, SW-6, SW-7, SW-8
Cyanide SW-1
-------
TABLE 6
SEDIMENT CLEANUP CRITERIA
Compound
4 -Hethylphenol
1 Benzole Acid
Phenanthrenc
Fluoranthrcne
Pyrene
Benz (a) anthracene'
Chrysenc
Benzo:(h) fluornnr.hr i! no
Bis(2-echylhexyl)-
ph thai ate
Benzo(l<) f luoranthrone
Benzo(a)pyrcne
Cammn -chl.ord.inn
AWQS/CV
ug/1
none
none
50
none
50
none
50
none
0.002
none
0.002
none
0.002
none
4
0.6
0.002
none
0.002
0.0012
0 . 02**
0.002**
Log
Kow
1.94
1.87
4.46
5.33
4.88
5.61
5.61
6.57
5.3
6.84
6 . 04
2.68
11 or A*
none
none
11
A
11
A
11
A
11
A
11
A
11
A
11
A
11
A
11
A
11
A
Sediment Cleanup
Criteria SS-3 (ug/Kg)
N/A
N/A
21,600
160,000
Ramapo Analytical
Results
SS-3 (ug/kg)
ND
ND '1
ND
40
56,900 . 46
12
12
110
12,000
1.800
210
33
20
0.18
0.018
ND
ND
ND
45
ND
ND
ND
* II: Human health ha.snd
A: Aquatic or^nnium health bnscd
**: AUQS/CV Cor chlordane
Sediment Cleanup Criteria (ug/kg) = AWQS/GV (ug/L) * 10lofl Kow * TOC
-------
TABLE 7
Phase II
Air Monitoring Program
VOA Analytical Summary
Ramapo Landfill
Parameter
2 - Buianone
1,1.1 - Trlchlorooiliano
CarDon Telrachloiide
Benzene
Chlorobenzeno
Ethylbenzene
Tetrachloroelhylene
Slyrene
Tolueno
Xylone (Tolal)
Melhylene Chloride
Aceiono
Units
mo/m'3
(ng/m"3
mg/m*3
mg/m'3
mg/m'3
mg/m"3
mg/m'3
mo/m'3
mo/(n"3
mgim'3
mg/m'3
mo/rn'3
TLV/300
1.97
6.37
0.10
0.10
1.15
1.45
1.13
0.71
1.28
1.45
0.58
5.03
VOC-1
0.0054
NO
NO
0.0007
NO
NO
NO
NO
0.0079
NO
0.0018 8
0.015 B
VOC-2
0.0079
0.0008
0.0002 J
0.0006
0.0005
0.0026
. NO
NO
0.0016
0.011
0.001 B
0.013 B
VOC-3
0.003
NO
NO
0.0003 J
NO
0.0008
NO
0.0005
0.0061
0.007
0.001 3 B
0.01 6 B
LPDW-1
0.0031
0.0011
0.0007
0.0008
NO
NO
ND
NO
0.0017
0.0025
0.0023 B
0.01 1 B
LPUP-t
NO
0.0013
NO
0.001
NO
0.0009
NO
ND
0.0038
0.0058
0.001 B
0.011 B
LPTB-1
NO
ND
NO
NO ,
ND
ND
NO
NO
ND
NO
0.0028 B
0.0061 B
PSP.-1
ND
NO
NO
ND
ND
ND
NO
ND
0.0004 J
ND
0.001 8
0.01 B
PSR-2
ND
NO
NO
0.029 E
0.37 E
1.20E
0.0041
NO
0.27 E
7.70 E
0.002 B
O.OOS7 B
PSR-3
0.0091
0.001
ND
0.0005
0.0007
0.0049
ND
ND
0.0011
0.016
0.0006 B
0.012 B
PSR-3O
0.0075
0.0007
ND
ND
ND
0.0012
NO
NO
0.0007
0.0046
0.0013 B
0.010 B
PSR-4
0.011
0.0011
0.0004
0.0006
ND
0.0009
NO
ND
0.0014
0.012
0.0008 B
0.011 B
PSR-4BT
0.018
NO
ND
NO
ND
0.0011
NO
0.0008
0.0013
0.016
0.003 B
0.018 B
PSR-TB
NO
ND
ND
ND
ND
ND
NO
NO
0.0004 J
NO
0.0034 B
0.012 B
NOTE: Samples were analyzed (or the complete TCL Volaliles list.
ND - None Detected
TLV - Threshold Limit Value as a Time Weighted Average; American
Conference of Industrial Hyglenlsts, 1990 - 1991.
J - Indicates the result Is less than the sample quanllllalion limit but greater than zero.
E - Estimated value due to Interference.
B - Analyle detected In the associated method blank.
-------
Table,. 8
GRQUNDVATS OeilCAiS OF POTENTIAL CONCEW
Benzene
Tecrachloroechene
Trichloroechene
l,&-Dichlorobenzene
Xsopropylbenzene
Tocal Xylene
Dlchlorodifluoroaechane
1,1-Oichloroechane
1.2-Dichloroe chane
p-Isopropylcoluene
cis-1.2-Dichloroechene
1,2,4-Trisechylbenzene
Carbon Disulfide .
Toluene
Acecone
Nickel
Propylbenzene Pyrene
Chlorosechane Arsenic
Chlorobenzene Caoaiun
Styrene Manganese
l,2*Dichlorobenzene Cobalc
1.3,5-Triaechylbenzenc Lead
cerc-Eucyibenzene * Sodiwa
Naphchalene Vanadiun
Oiechylphchalace Mercury
Sucylbenzylphchalace Oircoiu: (III)
Bis(2-echylhexyl)phchalace Alioinua
Di-n-occylphchalace Barivrp
delCa-2HC Calciua
giana-BKC Copper
&-Kechyl-2-pencanone Iron
?oca»ito Zinc
SOUAASTE CHEXICALS OF POTDfTlAL COHCEM
1.4-Oichlorobenzene
1.2-Dichlorobenzene
Benzoic Acid
Naphchalene •.
2-Hechylenaphchalene
Acenaphchene
Fluorane •
N-nicrosodiphenylamine
?henanchr«ne
Anthracene
Fluoranehtne
Pyrene
Bucylbenzylphchalace
Benzo(a)anchzac«n«
Chryiene
8is(2-echylh«xyl)phchaiac<
Di-n-occylphchala;j
aenzo(b)cluoranehen>
Benio(lc) fluer.anchcnt
Bcnzo(a)pyc«ne
Indeno(1.2.3-ed)'pyren«
Olbinzofuran
• AiR CHEMICALS
2-oucanone
Benzene
1.1,2.2-Tecrachlo roe chane
Chlorobenzene
Echylbenzene
Tocal Xylenas
Oieldrin
Chlordane
Hepcaehlor Epoxide
Berylliua
Cadaiua
Kercury
Tocal Phenols
of
cctJCc3:i
2•Sucanon*'
1.1.l-Trichloro«chane
Carbon T«crachlorld«
Bcnz«ni
Chlorobeniene
Echylbenzeiu
Tccracalorotchena
Scyrtna
Tolu*n«
Tocal Xyl*RU
Meehylen* Chloride
Acvcont
-------
Table 9
Potential Exposure Pathways
CURRENT LAND
USE
Trespasser/
Recreational
Off-site
Residential
Industrial/
Commercial
FUTURE LAND
USE
On-site
Residential
Industrial/
Commercial
RECEPTOR
Adult
Child (6-11yrs)
Adult
Child (6-11yrs)
Adult
Child (6-11yrs)
Adult
Child (0-6yrs)
Adult
Child (0-6yrs)
Adult
Adult
Adult
Child (0-6yrs)
Adult
Child (0-6yrs)
Adutt
Child (0-6yrs)
Adult
Child (0-€yrs)
Adult
Child (0-6yrs)
Adult
Adult
Adult
Adult
EXPOSURE
ROUTE
Ingestion
Dermal
Inhalation
Ingestion
Inhalation
Ingestion
Dermal
Ingestion
Dermal
Ingestion
Inhalation
Inhalation
Ingestion
Dermal
Ingestion
Inhalation
EXPOSURE
MEDIUM
Soil/Waste
Soil/Waste
Air
Groundwater
Air
Soil/Waste
Soil/Waste
Soil/Waste
Soil/Waste
Groundwater
Groundwater
Air
Soil/Waste
Soil/Waste
Groundwater
Air
-------
TABLE 10
TOXICITY VALUES: POTENTIAL NONCARCINOGENIC EFFECTS
J.f.t-jf . '
. . CHEMICAL :
Accnsphlhcnc
Acetone
Aluminum
Anthriccnc
Arsenic (d)
Barium
Bcn2o(£.h.i)pcrylenc (c)
Bcruoic Acid
Beryllium
Bis(2-cihylhciyl)phihalatc (d
2-Bulanonc (MEK)
lert-Bulylberucnc
Butylberuylphihalaic
Cadmium
Calcium.
Caibon Disulfide
Chromium (III)
Chlorobenzene
Cobalt
Copper
Cumcne (I'opropylbcnzcnc)
Cymenc (p-lsopropylloluene)
Dibenzofuran
1 .2-Dichlorobcrucnc
1.4-Dichlorobcnzcnc
Die hlorodi llouromcthane
l.l-Dichloroellianc
cii-l.2-Dicliloroctlicne
Dicldrin
Dicthylphihslate
Di-n-octylpSihalate
Eihylbenzene
Fluortnihenc
Fluorcne
Iron
Lead (d)
Liudane (gamma-HUC)
JclliTBHC
Manganese.
Mercury
Mclhylcne Chloride (d)
2-Mclhyinaphlhalcnc (c)
4-Meihyl-2-Penianone
Naphthalene
Nickel (d)
Phcrunlhrcne (c)
PhenolirfToul) •
Potassium
Propylbcnzenc
Pyrcnc
Sodium
Slyrene
Tetrachloroclhene
Toluene
1 . 1 . 1 -Triehleroclhanc
1.2.4-Trimcthylbcnzcnc
1.3.5-Trimethylbcnzenc
Vanadium
Xylenea. Toul
Zinc
Caibon Tclrachloridc (d)
Chlordane (d)
TOXICITY VALUES (ms/Vg-cUy)
SUBC1 IRONIC
INHALATION
•' Rfe
ND
NO
ORAL
' RfJ
6.00E-OI
I.OOE'OO
• cintONic
INHALATION
Rfc
NO
NO
ORAL.
RfJ
i.OOE-02
REF/SOURCE
SUBOKONIC
INHALATION
Uc
IIEAST
I.OOE-OI ! HEAST
D*u !n«dC44\wie for ^ui;-oi
5.00H-05
l.onU'Oo
2.l»l£-02
I.ME'OO
4.00K-OI
4.00U-OI
irujc4)u*u for
NO
l.OUU-01
4.00U-02
.'.ixiU-01 (.)
!.0<)i;-01
I.Ollli-OI
M)
NO
NO
NO
2.80E-01
ND
ND
.jiuiMiiiiivc rUk •»
NO
NO
3.00E-OI 1 HEAST
I.OOE-03 : IIEAST
3.00Em2 1 HEAST
4.00E-03 i HEAST
4.00E-00
3.00E-03
•HEAST
IIEAST
2.00E-02 HEAST
3.00E-OJ | IIEAST
4.00E-OI
2.00E-OI
3.00E-04 (c)
I.OOE-OI
I.ME'OO
l.OOE-02
I.OOE-03
ND
4.00E-02
4.00E-OI
ECAO
IIEAST
IIEAST
ECAO
IfEAST
HEAST
ECAO
HEAST
HEAST
ECAO
ORAL
R/d
IIEAST
IIEAST
HEAST
HEAST
IRIS
HEAST
HEAST
HEAST
IIEAST
HEAST
ECAO
irEAST
HEAST
IIEAST
IIEAST
HEAST
ECAO
HEAST
ItEAST
ECAO
d IRONIC
INHALATION
Rfc
HEAST
ItEAST
IIEAST
IIEAST
HEAST
HEAST
• HEAST
IfEAST
KEAST
HEAST
ECAO
HEAST
HEAST
HEAST
HEAST
HEAST
ECAO
HEAST
HEAST
ECAO
x*nnci» (IIEAST)
9.00E-02
NO
2.00E-OI
I.OOK-OI
I.OOI£'02
3.00E-03
I.OUE-OI
l.OOE-02
l.OOE-OI
4.00E-02
4.00E-02
MMmcM (IIIL^
NO
3.00I--04
HEAST
HEAST
IIEAST
IIEAST
IIEAST
IIEAST
IIEAST
HEAST
IIEAST
HEAST
IIEAST
IIEAST
IIEAST
IIEAST
HEAST
HEAST
HEAST
IIEAST
IIEAST
IIEAST
HEAST
IIEAST
IIEAST
IIEAST
IIEAST
IIEAST
IIEAST
KEAST
HEAST
IIEAST
HEAST
IIEAST
IIEAST
IIEAST
mis
IIEAST
IIEAST
IIEAST
IIEAST
ORAL
RTd
IRIS
IRIS
IRIS
HEAST
IIEAST
HEAST
BUS
mis
IRIS
IRIS
ECAO
IRIS
IRIS
IRIS
IRIS
IRIS
ECAO
HEAST
mis
ECAO
IRIS
IIEAST
IRIS
IIEAST
IRIS
IRIS
IRIS
IIEAST
IRIS
IRIS
IRIS
IRIS
IRIS
DATE
RECORDED
kfcrJ/Onl
4-FY50/FY9I
4-FY90/12-90
4-FY90/FY9I
4-FY90
4-FY90/H-9I
4-FY90
4-FY90/I-9]
4-FY90/9-90
4-FY90/9-19
4-FY90/«-90
4-91
4-FY90/9-I9
4-FY90/IO-J9
4-FY90/9-90
FY9I
4-FY9fy3-9l
4-91
4-FY90
4-FY90/4-9r
4-91
4-FY90/J-9I
4-FY90
4-FY90«-90
4-FT90
4-FY90/1-I9
4-FY90/9-90
4-FY90/9-I7
4-FY90
4-FY90/FY9I
FY9I
Pf9l
4-FY90/1-9I
4-FYSO/3-U
D*u uudtMruiilc for .tuiMiuiivc ritk titeMTMM (HEAST)
I.14E-04(>)
I.57E-OS (.)
I.5TE-OI (i)
I.OOE-OI
NO
NO
NO
NO
NO
NO
NO
J.7IE-01 (.)
i.ooK-oa
I.OOE-OI
3.00E-O4
6.006-02
4.00E-O2
5.00E-OI
4.00E-02
2.00E-02
4.00E-02
4.00E-OI n>)
4.00E-OI
I.OOE-OI
3. one. oo
1. ODE -01
l.OOC'OO
«.OOU-OI
I.UE-W'M
l.371i-03 (.)
!.)7i;-01 (i)
2.00E-02
ND
ND
Nil
Nil
NO
Ml
.•:)>
i.)n: at (.)
Linn-: m
I.OOE-OI
l.OOE-04
6.00E-02
4.006-0]
3.00E-02
4.00E-03
2.00E-02
4.00C-03
6.001: -01 (bl
4.006-01
3.00E-02
2.0UE-OI
i.noG-07,
2.00E-01
9.0UU-02
IIEAST
1IEAST
ItEAST
HEAST
HEAST
ICEAST
IIEAST
IIEAST
IIEAST
ECAO
HEAST
HEAST
IIEAST
IfEAST .
HEAST
HEAST
KEAST
HEAST
HEAST
HEAST
IIEAST
HEAST
HEAST
IIEAST
ECAO
HEAST
IIEAST
ItEAST
IIEAST
HEAST
IRIS
HEAST
HEAST
HEAST
HEAST
HEAST
IIEAST
HEAST
IRIS
ECAO
HEAST
HEAST
IEAST
HEAST
HEAST
IRIS
HEAST
BIS
IIEAST
mis
IIEAST
HEAST
IIEAST
IRIS
ECAO
IIEAST
IRIS
IRIS
IRIS
IRIS
4-FY90fIJ-90
4-FY90
4-FY9uVl-M
4-FY90
4-FY90/J-91
4-PT90
4-FY90
4-PT90
4-FY90/J-9I
4-91
4-FY90
4-FY90/9-90
4-FY9OV3-I1
4-Py90YI-90
4-FY90/9-90
D»u uujcqu«u for ^u*mri*iivc ruk •tacAtmcac (IICA^T)
D»u iimdcqiMIc for q:»Mri«4ivc n»k •4«cxcmBn< (II£A£T)
NO
I.JTU-01
NO
NO
NA
l.OOE-03
4.00E-00
2.00E-OI
7.00E-0)
«.om;.oi
Ml
i.]7l£-02
ND
M>
Ml
7.00U-0]
I.OOE-00
2.006-01
7.00E-04
4.00I--03
IFEAST
ItEAST
HEAST
IIEAST
IIGAST
HEAST
HEAST
IIEAST
IIEAST
IIEAST
IIEAST
BUS
HEAST
IIEAST
IIEAST
IIEAST
IRIS
IIEAST
IRIS
IRIS
4-FY90 '
4-FY90/FY9I
4-FY90
4-FY90O-9I
4-PT9IV7-I9
* - Phenol toticity valtica arc used.
•• - Calculated by analogy to anlimuny by correcting f.ir .lillvi. cues in inulccuUr wcirjlil.
> - Convened from inhalation Rfc (nig/m'3).
b - Developments I cfTccts have been uxd as the basis ••! cikuLiium
e - Tojieily values based on Oral RfJ for naphthalene (IIUAS'I -l-l-'YvO).
d - Refer to Table 6-21 for carcinogcni.: clfeeis.
e • Rfd is based on water.
1VN/OI80
-------
Table 11
Summary of Noncancer Risks
CURRENT LAND
USE
Trespasser/
Recreational
Off-site
Residential
Industrial/
Commercial
FUTURE LAND
USE
On-site
Residential
Industrial/
Commercial
RECEPTOR
Adult
Child (6-11yrs)
Adult
Child (6-11yrs)
Adult
Child (6-11yrs)
Adult
Child (0-6yrs)
Adult
Child (0-6yrs)
Adult
Adult
Adutt
Adult
Child (0-6yrs)
Adult
Child (0-6yrs)
Adult
Child (0-6yrs)
Adult
Child (0-6yrs)
Adutt
Child (0-6yrs)
Adult
Adult
Adult
Adult
EXPOSURE
ROUTE
Ingestion
Dermal
Inhalation
Ingestion
Inhalation
Ingestion
Dermal
Inhalation
Ingestion
Dermal
Ingestion
Inhalation
Inhalation
Ingestion
'Dermal
Ingestion
Inhalation
EXPOSURE
MEDIUM
Soil/Waste
Soil/Waste
Air
Groundwater
Groundwater
Soil/Waste
Soil/Waste
Air
Soil/Waste
Soil/Waste
Groundwater
Groundwater
Air
Soil/Waste
Soil/Waste
Groundwater
Air
HAZARD .
QUOTIENT
<0.01
<0.01
<0.01
<0.01
0.329
6.24 •
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
6.58
<0.01
<0.01
0.153 '
<0.01
1.79
3.10 •
0.085
0.057
19.2
42.6 %-
<0.01
<0.01
1.23
6.56
NONCANCER RISK SUMMARY
CURRENT-LAND USE
Trespasser/
Recreational
Off-site Residential
Industrial/
Commercial
FUTURE LAND USE
On-site Residential
Adult
Chad
Adult
Chfld
Adutt
Adult
Chfld
0.3
6
<0.01
<0.01
20
50
Industrial
Adult
-------
TABLE 12
TOXICITY VALUES: POTENTIAL CARCINOGENIC EFFECTS
CHEMICAL
alpha-BHC
Arsenic
Denzene
Denzo(a)anthracene (b)
)enzo(a)pyrene
Benzo(b)iluoranthene (b)
Benzo(k)fiuoranthene (b)
Beryllium
Bis('2-elhylhexyl)phthalate
Butylbenzylphthalate
Cadmium
Chloromelhane
Chrysene (b)
1 ,4-Dichlorobenzene
1 , 1 -Dichloroelhane
1 ,2- DicliloroeUianc
Dieldrin
alplia-Chlordane *
ganima-Chlordane *
Heplaclilor Epoxide
Indeno(l,2,3-cd)pyrene (b)
Lead
Lindane (gamma-DHC)
Methylene Chloride
Nickel
N-Nilrosodiphenylaminc
Styrenc
Tclrachloroelhene
1,1 ,2,2-Telrachloroethane
Trichloroethene
Carbon Telrachloride
SLOPE PACTORS (mg/kg-doy)*-!
INHALATION
6.30E+00
S.OOE40I«»
. 2.90E-02
6.IOE+00
6.10E400
6.10E*00
6.10EiOO
8.40E+00
ND
NA
6.10E*00
6.30E-03
6.IOE«00
ND
ND
9.IOE-02
1.60E+OI
I.30E«00
J.30E+00
9.10EiOO
6,IOE<00
NA
ND
4.70E-07
8.40E-OI
ND
2.00E-03
5.20E-07
2.00E-OI
I.70E-02
I.30E-OI
ORAL
6.30E+00
l.75E+00(a)
2.90E-02
.ISEiOl
.I5E*01
.ISE^Ol
.ISE-tOl
.30E+00
.40E-02
NA
ND
I.30E-02
I.I5E+OI
2.40E-02
ND
9.10E-02
I.60E+01
l.30E*00
1.30E+00
9.IOE+00
I.I5E+OI
NA
I.30E+00
7.50E-03
ND
4.90E-03
3.00E-02
5.IOE-02
2.00E-OI
1.IOE-02
I.30E-OI
WHIOHT-OF-EVIDENCn
INHALATION
D2
A
A
D2
B2
D2
B2
B2
B2
NA
Bl
C
B2
C
C
D2
B2
02
B2
B2
62
B2
B2-C
B2
A
B2
B2
B2
C
B2
B2
ORAL
B2
A
A
B2
B2
B2
B2
B2
B2
C
ND
C
B2
C
C
B2
B2
B2
B2
B2
B2
B2
B2-C
B2
ND
B2
B2
B2
C
B2
B2
TUMOR SITE
NHALATION
NA
Respiratory
Leukemia
Respiratory
Respiratory
Respiratory
Respiratory
Lung
NA
NA
Respiratory
Kidney
Respiratory
NA
NA
cs
Liver
Liver
Liver
Liver
Respiratory
NA
NA
Lung, Liver
Respiratory
NA
Blood
Leukemia, Live
Liver
Lung
Liver
ORAL
Liver
Skin
Leukemia
Stomach
Stomach
Stomach
Stomach
Total Tumors
Liver
NA
NA
Kidney
Stomach
Liver
Blood
CS
Liver
Liver
Liver
Liver
Stomach
NA
Liver
Liver
NA
Bladder
Respiratory
Liver
Liver
Liver
Liver
REFERENCE / SOURCE
INHALATION
IRIS
IRIS
IRIS
SPHEM
SPHEM
SPHEM
SPHEM
IRIS
IRIS
HE AST
IRIS
HEAST
SPHEM
IRIS
IRIS
IRIS
IRIS
IRIS
IRIS
IRIS
SPHEM
IRIS
HEAST
IRIS
IRIS
HEAST
HEAST
HEAST
IRIS
HEAST
IRIS
ORAL
IRIS
HEAST
IRIS
SPHEM
SPHEM
SPHEM
SPHEM
IRIS ..
IRIS
IRIS
HEAST.
HEAST
SPHEM
IRIS
IRIS
IRIS
IRIS
IRIS
IRIS
IRIS
SPHEM
IRIS
HEAST
IRIS
HEAST
IRIS
HEAST
HEAST
IRIS
HEAST
IRIS
DATE ,
RECORDED
NHAL/ORAL
. . 4-91
2-9I/4-FV90
1-91
1986
1986.
1986.
1986
1-91
5-90
4-FY90/2-89
3-9I/4-FY96
4-FY90
1986
12-90
1-90
1-91
1-91
1-91
1-91
1-91
1986
2-89
4-FY90
1-91
8-91/4-FY90
4-FY90/3-88
4-FY90
4-FY90
1-91
4-FY90
1-91 .
Notes: ,
* - Slope factors are obtained for the chemical chlordane.
** - An absorption factor of 30% is used to calculate unit risk from the slope factor.
CS - Effects circulatory system.
BW - Effects body weight.
NA - Not applicable.
a - Calculated from oral unit risk of 5E-5[/ig/L]-l
(HEAST 3-FY90).
b - Toxicity values for Benzo(a)pyrene were used for all
carcinogenic PAIIs when data were otherwise unavailable.
ND - Not determined.
IRIS - Integrated Risk Information System. Dale indicates last update by EPA. Access to IRIS was March, April 1991.
HEAST - Health Effects Summary Tables. Date indicates quarter and Fiscal year for which table was published.
SPHEM - Superfund Public Health Evaluation Manual, USEPA 1986.
-------
Table 13
Summary of Cancer Risks
CURRENT LAND
USE
Trespasser/
Recreational
Off-site
Residential
Industrial/
Commercial
FUTURE LAND
USE
On-site
Residential
Industrial/
Commercial
RECEPTOR
Adutt
Child (6-11yrs)
Adult
Child (6-11 yrs)
Adult
Child (6-11 yrs)
Adult
Child (0-6yrs)
Adutt
Child (0-6yrs)
Adult
Adult
Adult
Adult
Child (0-6vrs)
Adult
Child (0-6yrs)
Adutt
Child (0-Syrs)
Adutt
Child (0-6yrs)
Adutt
Child (0-6yrs)
Adutt
Aduft
Adutt
Adutt
EXPOSURE
ROUTE
Ingestion
Dermal
Inhalation
Ingestion
Inhalation
Ingestion
Dermal
Inhalation
Ingestion
Dermal
Ingestion
Inhalation
Inhalation
Ingestion
Dermal
Ingestion
Inhalation
• EXPOSURE .
MEDIUM
Soil/Waste
Soil/Waste
Air
Groundwater
Groundwater
Soil/Waste
Soil/Waste
Air
Son/Waste
Son/Waste
Groundwater
Groundwater
Air
Soil/Waste
Soil/Waste
Groundwater
Air
CANCER
RISK
2.25E-6
2.88E-6
4.82E-7 •
3.73E-6
8.55E-7
4.55E-6
1.97E-8
3.68E-9
5.38E-10
2.51 E-10
5.B3E-6
4.58E-6
1.71E-5
8.22E-6
1.28E-5
1.76E-6
5.27E-6
1.03E-4
3.19E-5
5.38E-6
1.39E-6
5.00E-5
3.10E-5
5.63E-6
4.58E-6
7.03E-5
1.71E-5
CANCER RISK SUMMARY
CURRENT LAND USE
Trespasser/
Recreational
Off-site Residential
Industrial/
Commercial
FUTURE LAND USE
On-site Residential
Adutt
Child
Adutt
Child
Adutt
Adutt
Child
4E-6
1E-5
2E-8
4E-9
3E-5
2E-4
8E-5
Industrial
Adutt
1E-4
-------
TABLE 14
SUMMARY OF CAPITAL, OPERATION AND MAINTENANCE, AND PRESENT WORTH COSTS
FOR ALL REMEDIAL ALTERNATIVES ASSOCIATED WITH THE
RAMAPO LANDFILL SITE
ALTERNATIVE
Alternative 1: No Further Action with Monitor-
ing
Alternative 2: Limited Action (with Option for
Alternate Water Supply)
Alternative 3: Installation of Groundwater
^ Extraction Wells
Alternative 4A: Landfill Cap; Installation of
Groundwater Extraction Wells
Alternative 4B: Landfill Cap; Installation of
Groundwater Extraction Wells
Alternative 5: Landfill Cap with Soil Cover on
Side Slopes; Installation of
Groundwater Extraction Wells
CAPITAL COST
$0
$190,000 - $710,000
$1,040,000 -$3,300,000
$26,170,000 - $29,310,000
$21 ,870,000 -$25,010,000
$18,390,000 -$21 ,640,000
OPERATION AND
MAINTENANCE COST
$345,700
$345,700
$547,300 -$1,1 56,000
$319,600 - $622,600
$319,600 - $622,600
$319,800 - $678,600
PRESENT WORTH COST
$3,260,000
$3,380,000 - $3,970,000
$6,206,000 - $14,210,000
$29,190,000 - $35,760,000
$24,890,000 - $30,880,000
$21 ,41 0,000 -$28,050,000
------- |