United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R02-87/042
September 1987
©EPA
-------
DECLARATION FOR THE RECORD OF DECISION
SITE. NAME AND LOCATION
Suffern Village Well Field, Suffern, Rockl~nd County, New York
STATEMENT OF PURPOSE
This decision document represents the selected remedial action
for the Suffern site de~eloped in accordance with the Compre-
hensive Environmental Response, Compensation, and Liability Act
of 1980, as amended by the Superfund Amendments and Reauthoriza-
tion Act of 1986, and to the .extent practicable, the National
Oil and Hazardous Substances Pollution Contingency Plan, 40 CFR
Part 300, November 20, 1985.
. .
STATEMENT OF BASIS
This decision is based upon the administrative record for the
Suffern Village Well Field site. A .copy of the record is
available for review at the information repository for the site
and at the regional office. The following documents, which are
part of the administrative record, were primarily relied upon
in making this decision:
- Remedial Investigation Report, Suffern Well Field, prepared
by ERM-NORTHEAST, July 1987
- Feasibility Study Report, Suffern Well Field, prepared by
ERM-NORTHEAST, August 1987
- The attached Decision Summary for the Suffern Well Field site
- The attached Responsiveness Summary for the site, which
incorporates public Comments received
Staff summaries and recommendations
..
DESCRIPTION OF THE SELECTED REMEDY'
Of the various alternative remedies considered, a no action
alternative has been selected for this site. Due to the
presence of only moderate levels of contaminants and predicted
low levels in the future, this is deemed to be an. appropriate
choice. Applicable or relevant and a~pr6priate requirements
'(ARARs) at the point of groundwater wlthdrawal and use are not
now and are not predicted to be exceeded. Further, no long-term
negative impacts on soil or surface water are anticipated.
Nevertheless, in order to confirm the adequacy of this alternative
selection, an extensive monitoring and reevaluation program is
included. This monitoring program will serve as an early
warning of unanticipated contaminant levels, which is a prudent
precaution in consideration of uncertainties in aquifer behavior
-------
~ ,.
-2-
DECLARATIONS
The selected remedy is protective of human health and the environ-
ment, attains Federal and State requirements that are applicable
or relevant and appropriate,' and is cost-effective. The statu-
tory preference for treatment need not be satisfied because treatment
was found to be unnecessary for meeting ARARs. Drinking water
standards are currently being met and have been met in the recent
past, without treatment.
Although contaminants will exist at concentrations exceeding
standards in certain locations in the aquifer for several years,
predicted natural attenuation will reduce these concentrations
to allowable limits in approximately 2 years. Access to the
aquifer should be restricted until such time as ARARs are met
therein.
The State of New York has been consulted and agrees with the
approved remedy (see attached letter).
Start-up of the monitoring program which is eligible for Superfund
monies for a period of up to one year, includes aquifer model
verification and all associated sampling and analysis required
for said verification. . The action will require future operation
and maintenance activities to ensure the effectiveness of the
monitoring program. All such activities are the responsibility
of New York State.
..
I have also determined that the action being taken will be
appropriate when balanced against the future availability of
Trust Fund monies for use at other sites.
S£tJ1~.~\J fA. t. S) (f J2
-------
.
\J
TECHNICAL REPORT DATA
(PlelUt read Instrucllo"s 0" the revene befrxe com"leti"rJ
1. REPORT NO. \2. 3. RECIPIENT'S ACCESSION NO.
bpA/ROD/R02-87/042
4. TITL.E AND SU8TITL.E 5. REPORT DATE
~UPER=UND RECORD OF' ;)ECISION S~Dt~mb~r 25. 1987
l3uEf.:rn Villas.: \-7.:11 Fi.:ld, :~y 6. PERFORMING ORGANIZATION CODE
Foirs': K-::ffi.:cia1 .:"ct ion - :.:'ina1
7. AuTHORISI 8. PERFORMING O'.NIZ.>.T1CN MEi'ORT ',0
9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM EL.EMEN.T NO.
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND AOORESS 13. TYPE OF REPORT AND PERIOD COVERED
U.S. EnvirQnm.:ntal Protection Agency Final ROD RePurt
401 M Stre.:t, S.W. 1.. SPONSORING AGENCY CODE
!washingtun, D.C. 20460 800/00
15. SUPPL.EMENTARY NOTES
18. ABSTRACT
The Suffern Village Well Field site is lucated in Ruckland Cuunty, New York. Tho:
Village of Suffern operates four pruduction wells that pruvide water to approximately
12,000 people. In September 1978 monitoring activities detected l,l,l-trichloroethane
(TCEA), a common industrial chemical compound, and trace VOCs in tho: municipal water
distribution system. In December 1978, wells 1,2 and 4 with TCEA levels of 90-114 ppb
were shut duwn. Municipal water supply requirements were met by well 3. A subsequent
survey identified the Tempcon Corporation, a small lucal oil burner reconditioning
business, as the source of TCEA. In January 1979, Tempcon ceased using a seepage
dispusal pit and TCEA-based cleaning pruducts. By March 1979, removal of waste material
and excavation and devolatilization of contaminated soils were completed. A spray
aeration treatm.:nt system was then implemented to remov.: TCEA from th.: municipal water
supply. Munituring results indicate TCEA levels in the four wo:lls b.:low the New York
State Do:partment of Environmental Conservation (NYSDEC) guideline of 50 ppb.
A no action remedy with ground water munitoring to assure the presence of TCEA at
concentrations below the NYSDOH action level is the selo:cted remedial action. The
estimated preso:nt worth cost for this ground water monitoring is $311,000.
11. KEY WOROS ANO OOCUMENT ANAL.YSIS
a. OESCRIPTORS b.IOENTIFIERS/OPEN ENOEO TERMS C. COSA TI Field/Group
Record of Decision
Suffern Village Well Field, NY
First Remedial Action - Final
contaminated Media: gw
Key contaminants: TCEA, VOCs
18. OISTRIBUTION STATEMENT 19. SECURITY CL.ASS (Tlus RtpOnl 21. NO. OF PAGES
None 47
20. SECURITY CL.,ASS (This pagtl 22. PRICE
Nune
!'A '.,,111 2220-1 (R...4-77)
-------
~ "
INSTRUCTIONS
,.
REPORT NUMBER
Insert rhe ~p,,, report number U It appears on the cover o(the pubh':~lIon.
2.
3.
L.EAVE BL.ANK
RECIPIENTS ACCESSION NUMBER
Reserved for use by ~a.:h r~port Cel.:lplenl.
4.
TITLE AND SUBTITLE
Title should Indicate dcarly .lnd bnelly (he sub)el:t ,'overa~e vI' Ihe c,'port. Jnd be Jhl'lay,'J prulllln,'nlly, S,', ,,,"1111.',11 11,,'d, 111 "lIail,'c
type or otherwise subordinate II 10 main title, When a ceport I> prep~red In mon° than t Juthor', affihallUII .1' il .1.1'1',." frul1l Ilw 1'...rfuCllllnt: "'\tam-
ution.
8.
PERFORMING ORGANIZATION REPORT NUMBER
Insen If performing orgamZlllon wIshes to a~slJft this number.
9.
PERFORMING ORGANIZATION NAME AND ADDRESS
Give name, street. city. state. and ZIP code. List no more than IWO levels of an urt::Jl1IlaIiUllal hire:.rdlY,
10. PROGRAM ELEMENT NUMBER
Use the propam element number under which Ihe report was prepared. Suboruillah: number, lI\a)' l~ 111,'1\1,1.'11 111 l'ar"lIlh,'"",
11. CONTRACT/GRANT NUMBER
Insert conttact or grant number under which report wu prepared.
12. SPONSORING AGENCY NAME AND ADDRESS
Include ZIP code.
13. TYPE OF REPORT AND PERIOD COVERED
Indicate interim liM!, etC'., and If applicable, dates covered.
14. SPONSORING AGkNCY CODE
Insert appropriate code.
15. SU""-EMENTARY NOTES
Enter information not Included elsewhere but useful. such ~s: Prep:.red IIIl:ooper:.lllon wllh. I"r"II,lall"II III. 1''''''''IIlc,1 011 '-"""',,'''',' ,,',
To be published in. Supersedes. Supplements. ~tc.
18. ABSTRACT
Include a brief (200 WOTds 0' Itn) factual summary of the most "lInllk:.nt &nformall..n ,'untalncd III 110,' "'l'or1. II I h,' "'1''''' ""1';1111' ~
significant bibliography or literature survey. men lion II here.
17. KEY WORDS AND DOCUMENT ANALYSIS
(a) DESCRIPTORS. Select from the Thc~uru~ of !:nglnecrir.. and S':ICllllli.: Terms the pruper aUlh"rllcu ICClII' thatlucnllly Ihc "Ia/llr
concept of the research and are sufficiently specific ~nu precl~ to be u~u as &nuc, cntrlcs fur ~..tah'~lnl!.
(b) IDENTIFIERS AND OPEN.ENDED TERMS. Use identifien (or prolcct n:JnM. cudc nilmcs. e4u1pmcnt ,k'l~nOllors. eI\:, LIse /)f~n.
ended terms written In descriptor (orm for those subJeclS (or which no dcscrlptur e.\lsl5.
(c:i COS,", TII'IELD GROUP. Held ..nd group usilnments ,ue to be t:Jkcn frum the 1965 ('05"'11 Suh".I.:' Cal"j!ory I.ist. Slnc,' the "1;1-
jority of aocumenu are multidisciplinary In nature, Ihe Primary "ield/Group :.IsSlgnml:nlf" will bc 'I"'" II '" UI" Iphne. arc:J "I hUlllan
endeavor. or type of physi.:ai object. The applicallonh) will be cru~~.rct'crl:nce:u wllh ",,'unuary 11\'1<1/( ;rll"f' a"II=IIlIIcII" Ihal "'11111111..14
the primary posllngts).
18. DISTRIBUTION STATEMENT
Denote releasablhty to the pubhc or hnlltJIIOn for reason~ other th..n ,cl.:uraly fur cJlaml'le "I(clca'c 1,111111111"11." ( 11,' allV a,.III;,!>,Io,)' 'U
the public. with o1ddress and pnl.:c.
19. a. 20. SECURITY CLASSIFICATION
DO NOT submit cla~~lfjed reports to the: NOillon..1 Tel.:hnlC:JllnformOltiun ..crvlcc.
21. NUMBER OF PAGES
Insen the total number of pages. Including this one: and unnumbered palll:'. bul cxdudc u.'lrabullun 10'1, 11 any,
22. PRICE
Insert the price set by the National rechnicallnformallon S.:rvlcc ur thc Govcrnmenll'ranllng Offil.:c. I' knuwn,
-------
. ~
Sm~MARY OF REMEDIAL ALTERNATIVE SELECTION
SUFFERN VILLAGE WELL FIELD
NEW YORK
..
United States Environmental Protection Agency
Region II
New York
-------
. ~
TABLE OF CONTENTS
PAGE
Ie SITE LOCATION AND DESCRIPTION 1
II. SITE HISTORY 1
III. ENFORCEMENT 5
IV. COMMUNITY RELATIONS 5
V. ALTERNATIVES EVALUATION 6
A - Description 7
B - Public Health Evaluation 9
C - Evaluation of Alternatives in Comparison 10
to Specific Criteria ..
VI. SELECTED REMEDY 18
A - Description 18
B - Statutory Determination 19
ATTACHMENTS
-.
A.
NYSDEC Letter of Concurrence
B.
Responsiveness Summary
-------
FIGURE
1-1
1-2
2-1.
2-2
2-3
2-4
2-5
5-1
5-2
5-3
5-4
5-5
5-6
TABLE
2-1
2-2
5-1
5-2
FIGURES
TITLE
General Vicinity Map
Locations of Wells
Average Monthly TCEA Concentrations
Suffern Wells
Location of Tempcon Test Pits
Location of E-Site Test Pits
TCEA Concentration Map
Samples of October 1986
TCEA Concentration Map
Samples of December 1986
Alt.1-TCEA Concentration in Production
Wells vs Time
Alt.1-TCEA Concentration in Aquifer -
Dec. 1987
Alt.1-TCEA Concentration in Aquifer -
Dec. 1991
Alt.1-TCEA Concentration in Aquifer
De c. 19 9 6
Alt.4-TCEA Concentration in Aquifer -
Dec. 1989
Alt.6-TCEA Concentration in Aquifer -
Dec. 1992
TABLES
TITLE
Water Quality Data - October 1986
Water Quality Data - December 1986
Alternative No.1 NO-Action
Projected Contaminant Concentration
vs ARARs
Summary of the Evaluation of
Alternatives
ii
PAGE
20
21
22
23
24
25
26
27
28
29
30
..
31
32
PAGE
-
33
34
35
-------
, .
II.
-1-
I.
SITE LOCATION AND DESCRIPTION
The Suffern Village Well Field site is located in the north
eastern portion of the Village of Suffern, New York. The
well field is approximately 0.25 miles north of the New
York-New Jersey border in Rockland County and covers an area
. of approximately 30 acres in the Ramapo River valley.
The study area lies on the relatively flat alluvial floor of
the Ramapo River Valley approximately 2,500 feet north of the
confluence of the Ramapo and.Mahwah Rivers. Topographic
relief is in the order of 660 feet: the uplands are at eleva-
tion 930 feet (ASL) and the 100 year flood plain is at eleva-
tion 270 feet (ASL). Slopes 'as steep as 40% are found along
the valley walls. The New York State Thruway, U.S. Route
17, New Ybrk State Route 59, and a Conrail right-of-way all
pass through' the study area (Figure 1-1).
The Ramapo River is categorized by the NYSDEC as a nC1ass
A Water". It is therefore best utilized for potable water
supply or as a supply of water for food processing operations~
/
The portion of the study area south of the Thruway has been
characterized as one of three major flood areas within the
Ramapo Valley in Rockland County.
~
The Village of Suffern operates four production wells that
provide water at an average rate of approximately 1.8 million
gallons per day (MGD), to a population of approximately
12,000 people. The well field consists of four gravel-packed,
production wells completed in the valley-fill, glacial out-
wash sediments of the Ramapo River Valley (Figure 1-2).
Recharge to the wells is derived principally from induced
infiltration of water from the Ramapo River. Other sources
include infiltration of run-off from upland areas, direct
precipitation onto the valley floor and underflow along the
valley. .
SITE HISTORY
Volatile organic contamination of the Village of Suffern
Well Field was detected in tap wate~ collected from the
municipal distribution system in September, 1978. Sub-
sequent monitoring activities by the Village, the Rockland
County Health Department (RCHD) and the New York State
Department of Environmental Conservation confirmed that
ground water at the Suffern Well Field had become contami-
nated with l,l,l-trichloroethane (TCEA), a'common industrial
chemical compound with several uses. Only traces of other
-------
-2-
concentrations approaching those of the TCEA, and in all
cases below NYSDOH guidelines. Wells 1, 2, and 4 with TCEA
levels of 90 to 114 parts per billion (ppb) were shut down
in December of 1978; the Village water supply requirements
were provided by Well #3, which had TCEA levels well below
the NYSDOH guideline of 50 ppb.
Several actions were implemented as a result of these find-
ings. These included a survey of local commercial establish-
ments in order to identify the source of the TCEA which
culminated in the discovery that the Tempcon Corporation,
a small oil burner reconditioning business, had used TCEA
prior to the discovery of the TCEA ground water contamination.
No other TCEA users were identified. In January of 1979, ~
Tempcon ceased using a seepage disposal pit as well as TCEA- /
based cleaning products. Subsequently, under the guidance
of the RCHD, remedial measures including the removal of
waste materials from its disposal pit and the excavation
and devolatilization of contaminated soils, were completed
in March, 1979. The contaminant levels in the ground water
were not immediately affected.
The Village then constructed a spray aeration treatment
system later that year to remove the TCEA from the munici-
pal supply. Based on the prevailing contaminated condition
of the site, it was placed on the National Priorities List
in October, 1984. Monitoring results have shown that TCEA
levels are within the NYSDOH guideline of 50 ppb; therefore
the treatment system has not been needed since the beginning
of 1985. RCDH (May 10, 1985) advised the Village that wells
#1 and #4 could be utilized without aeration.
~
'-Since May, 1985, when well #3 was taken out of service for
redevelopment, the TCEA concentrations in all four wells
have remained below the NYSDOH guideline with only occa-
sional excursions. Well #3 went back in service in late
1985 and TCEA levels have remained below 15 ppb. At
present, TCEA levels are still consistently higher in Well
#4 but the ranges of values are significantly lower than
in previous years. Currently, the highest values recorded
as of February, 1987 are in the 25-30 ppb range.
The contamination history of the Suffern Well Field is unusual
in that only one contaminant has been persistent although
trace levels of other organic chemical species have been
periodically detected. Since the cessation of subsurface
-------
b
-3-
at Tempcon, the. water quality of the Suffern wells has grad-
ually improved over several years, such that current concen-
. trations of TCEA are below the NYSDOH. "action guidelines."
In summary, previous investigative efforts have recognized
. the TCEA contamination problem to be the probable result
of the discontinued disposal practices at the Tempcon
Corporation. The complex nature of the site hydrogeology
had prevented the thorough understanding of the behavior of
TCEA within the glacial aquifer thereby resulting in the
belief that there might be other sources of TCEA. Equally
importantly, there existed a concern that even though the
suspecteq source had been remediated, slugs of contaminants
may have been released into the subsurface thereby causing
the well field to be continually under the threat of periodic
contamination above the NYSDOH guidelines.
The trend in TCEA concentrations from November 1978 to
February 1987 is shown on Figure 2-1. For a detailed dis-
cussion, refer to the Remedial Investigation Report, July
1987, Section 5.2.2.1. .
. .
.
~
A remedial investigation of the well field was undertaken in
April, 1986, in order to identify all sources of contamina-
tion within the well field and adjacent areas.
The scope of the field work included a soil sampling program
and a water sampling program. The former included testing
for VOCs in soils at twelve deep test boring locations and
characterizing soils in test pits at Tempcon and the E-well
site. The location of the borings are shown on Figures 2-2
and 2-3.
For the water sampling program, a total of 24 wells were
installed in individual well, two-well and three-well
cluster configurations. Locations are shown on Figure 1-2,
and the details of the installation are described in the
Remedial Investigation Report.
Subsequent to initial sampling, two' comprehensive rounds of
water samples were taken in October and December, 1986.
TCEA and associated impurities and/or degradation by-products
have been detected in several of the wells installed through-
-------
-4-
an approximation of contamination as shown on the attached
TCEA isoconcentration maps on Figures 2-4 and 2-S.Concentra-
tions of associated impurities have likewise been measured
or estimated.
. The distribution of TCEA-related contamination within the
aquifer is such that supply wells still yield ground water
with TCEA in quantities ranging from one to 30 ug/L. The
nearby Spring Valley Water Company production well #100,
located due east of Tempcon also contains TCEA in similar
concentrations. .
The highest observed concentrations of TCEA and other VOCs
is located at the "E-well location"; values of TCEA ranged
from 30 ug/L to 1500 ug/L. A second area to the south, the
"I-well location", contained elevated concentrations of
TCEA ranging from 30 to 75 ug/L.
No data has indicated that metals, other inorganics semi-
vOlatiles, and other VOCs, could affect human health or
the environment and they were not considered indicators.
~
No ambient air, surface soil, sediment or surface water
pathways of significant release are indicated by the results
of the RI. The only pathway of concern considered in depth
has been via ground water migration from Tempeon and the E-
site as well as from a former gas works facility.
As a result of a risk assessment, it is believed that the
long-term exposure to the toxic constituents identified
during the RI pose only a negligible health hazard. A
detailed presentation of this risk assessment is included
in the Remedial Investigation report, dated August 1987,
whi~h is part of the Administrative Record.
Coal tar related waste materials appear to be present in
unknown quantities near the well field. These apparently
derived from a former gas works plant located near the well
field. This facility operated from. 1902-1935. At the very
low concentration levels detected in either the soils and/
or ground water, the detected PAHs are considered to be
only a very minor concern from a human health and environ-
mental standpoint.
A solute transport model (Suffern Aquifer Model) has been
developed that utilizes all available information in the
study area, and is capable of predictive simulations of
contaminant concentration profiles as a function of time.
Future sampling/analyses are reqired to confirm the vali-
-------
-5-
III.
ENFORCEMENT
At the time of the initial detection of the contaminant
TCEA, the Rockland County Health Department investigation
indicated that the Tempcon Corporation was the potential.
. source. Remedial measures, including excavation and disposal
of a concrete seepage pit into which wastes had reportedly
been deposited and the treatment of contaminated soils,
were performed. Nevertheless, elevated TCEA levels persisted.
By letter of February 22, 1985, Tempcon was advised that EPA
intended to perform an RI/FS at the site: also, that Tempcon
might be.a responsible party and subject to liabilities.
Tempcon responded on March 5, 1985 indicating no knowledge
of data or investigations leading to the EPA action.
Based upon this response, EPA determined that there was
little likelyhood of Tempcon participation in the study.
EPA therefore signed a cooperative agreement with New York
State on March 29, 1985 to undertake the RI/FS.
~
Although no remedial action is contemplated at this time, an
extensive monitoring program will be implemented to ensure
protection of public health and to verify the results of the
model. Should the model prove defi~ient thereby indicating
contamination which might jeopardize public health, a second
operable unit may be initiated. to remediate the problem.
EPA maintains its right to initiate enforcement action
against Tempcon for recovery of all relevant costs, including
the cost of the RI/FS and any subsequent actions taken to
protect public health.
COMMUNITY RELATIONS
IV.
The first known public attention was focused on the site io
August 1978 when some residents living in Rockland County
began to complain about the taste of their water. After
the Rockland County Board of Health tested several community
water supplies and found TCEA in the Suffern wells, the
village installed an aeration system.
When news of the contamination first became public, local
residents besieged the mayor's office with questions and
complaints. These complaints ended after a local newspaper
article, dated December 14, 1978, reported that the contami-
nation level in the Suffern water supply had been decreased
-------
-6-
In March 1980, when the aeration system was shut down after
a heavy rain storm and the community was advised to boil
its drinking water, local newspapers carried the story.
Also, after further testing, the mayor announced that the
water was safe to drink again, and this was covered in the
"media.
No other community involvement with the site has been docu-
mented. There are no known citizen groups in the area.
Although no public meetings have been held (prior to Our
August 19, 1987 meeting) for the purpose of discussing the
Suffern Village Well Field site, the issue has been raised
at several town Council meetings. Also, at a Village
meeting on July 14, 1986, DEC presented the program and
objectives of the RI/FS that was about to be initiated.
Community awareness at the site can be characterized as " :
moderate. It is important to note, however, that this level- ;
of interest will become much greater if there is an increase ~
in the ground water contamination.
Specific concerns that were raised during the public Comment
period,. including comments.made at the public meeting held
on August 19, 1987 ~t the Suffern Town Hall, are answered in
the attached Responsiveness Summary. A transcript of the
hearing is included in the Administrative Record which is
available for review at the information repository and at
the regional office.
V.
ALTERNATIVES EVALUATION
The remedial alternatives for the Suffern Well Field site
were developed and evaluated using the Comprehensive Environ-
mental, Response, Compensation, and Liability Act of 1980
(CERCLA), as amended by the Superfund Amendments and Reauthor-
ization Act of 1986, the National Oil and Hazardous Substances
Pollution Contingency Plan (NCP), 40 CFR S300.68, and the
"Guidance on Feasibility Studies Under CERCL;A", as guidance.
According to Section 121 of CERCLA, the recommended remedial
alternative must protect human health and the environment,
should be cost-effective, and should utilize permanent
solutions and alternative treatment or resource recovery
technologies to the maximum extent practicable. The proposed
remedy must also attain applicable or relevant and appropriate
federal and state public health and environmental require-
ments (ARARs) that have been identified for the site. The
-------
-7-
A three step process was developed and used to facilitate
the selection of a preferred remedial alternative. The
following is a summary of that process:
1.
Selection of remedial technologies and general
alternatives.
2.
Further development and screening of remedial
alternatives.
3.
Detailed evaluation of the final alternatives.
Complete.details of these analyses are presented in the
Feasibility Study Report, dated August, 1987: the results of
Step 3, are presented herein. Note that the decision is
based on nine alternatives initially screened. The remaining
five alternatives are presented in accordance with the numbe~-
ing system utilized in the Feasibility Study (Table 5-3).
A - Description
..
Alternative No.1 - No Action
No active remedial measures would occur: no ground
water pumping, diversion, treatment or other activity
would be contemplated. Management and use of the
Ramapo River Valley aquifer would continue in its
present manner, including major withdrawals by the
Spring Valley Water Company and Suffern Village.
Monitoring of the ground water is the only activity
included.
Alternative No.2 - Treat Suffern Water Supply,Using
The Existing Spray Aeration System
This system would be relied on to meet public health
standards. Rehabilitation of the spray aeration system
is required to provide treatment capacity up to the
maximum system demand, and to achieve long term, highly
reliable treatment for the expected period of aquifer
contamination. Monitoring of water quality is included.
Alternative No.3 - ~~~~~ds~~~:~nA:~;~~O~u~~) ~~~~~ma
Removal of the volatile organic compounds would be
accomplished via packed tower aeration. The salient
-------
-8-
a)
Ground water withdrawal tates in
accordance with existing requirements.
b)
Treatment of flows from all Suffern
wells with capacity to treat two
wells simultaneously.
c)
Continuous treatment as long as it takes for
restoration of the aquifer.
d)
Long term standby capability, if
required.
e)
Minimal required monitoring of
system performance.
Alternative NO.4 - Plume Containment, by Extraction at
POlnt(s) of Maxlmum Contamlnatlon;
Treat w/PTA and Discharge to River. :
This remedial action comprises two major components:
a)
b)
~
Ground water pumping
Treating contaminated ground water
for discharge into the Ramapo River.
This depends on ground water modeling
for optimum scheme for aquifer resto-
ration and ground water plume contain-
ment. . Objective is to remediate the
aquifer as Soon as practicable.
Alternative No.. 6 -
No.3
to
This alternative would essentially divert the contami-
nant plume using an existing production well (or wells).
The program depends on a model prediction of plume
migration and characteristics. . Spring Valley Well #100
or Suffern production wells, or a combination thereof,
would pump at maximum rate to maintain an inward gradi-
ent throughout the plume. A PTA system for the Suffern
Wells would remove VOCs to comply with ARARs, and then
the treated water would be pumped to the Suffern distri-
-------
-9-
B - Public Health Evaluation
The ground water transport-dispersion model was used to
estimate concentrations of TCEA in ground water over time at
identified points of interest. Estimates of the concentra-
tions of related "dichloro" compounds, based on TCEA levels
were then derived for the affected water. Concentrations of
those compounds with evidence of animal carcinogenicity
were expressed in terms of lifetime equivalent concentrations.
Exposure routes and the degree of exposure via each route
were estimated. Risks were then calculated for the level of
carcinogen(s) in the affected water in the absence of any
remedial activity, and for each of the remedial alternatives.
Non-carcinogenic hazards were also examined.
Alternative No.1 - No Action
Under Alternative No.1 the 70-year equivalent concentra--.
tion of TCEA in the Suffern well water was calculated: :
to be 0.29 ug/L. At present there is inadequate evidence~
to rank TCEA as a possible human carcinogen. The 70-year
equivalent concentrations in Suffern public water supply
were estimated ,to be 0.006 ug/L for 1,2-dichlorethane
and 0.064 ug/L for 1,1-dichloroethy1ene. The excess
lifetime cancer risk associated with the model predicted
concentrations of 1,1-dichloroethylene was estimated to
be 7 X 10-6. That is, there is a 5% probability that more
than 7 cases of cancer would develop out of a population
of 1 million people so exposed, and a 95% probability
that there would be less than 7 cases out of 1 million.
The excess lifetime cancer risk associated with 1,2-
dichloroethane was estimated to be 3 X 10-8.
Non-carcinogenic risks were estimated to be negligible.
The risks associated with each remedial alternative were also
calculated; the total excess lifetime cancer risks are tabu-
lated below. Other risks were estimated to be negligible.
ALTERNATIVE
No.1
No.2
No.3
No.4
No.6
ESTIMATED LIFETIME CANCER RISK
7 x 10-6
7 x 10-6
6 x 10-6
5 x 10-6
-------
-10-
C - Evaluation of Alternatives in Comparison to Specific
CrIterIa
The specific criteria to be evaluated include regulatory
requirements (e.g. ARARs), performance, reliability, im~le-
. mentability, effectiveness, environmental impacts, instI-
tutional concerns and cost. These criteria were derived
from the "Guidance on Feasibility Studies Under CERCLA",
1985, and the factors in SARA Section 121(b)(1), A-G. The
following analysis summarizes the above from the Feasibility
Study.
Alternative No.1 - NO-Action
Low levels of contaminants are predicted as shown on
Table 5-1. As noted there, no ARARs are predicted to
be exceeded at the existing points of withdrawal of
ground water, Le., at the production wells. Therefore,-
the no action alternative appears to satisfy the require-;
ments of SARA concerning cleanup standards. Only natural~
processes would act to permanently reduce the toxicity
and/or mobility of contaminants. The predicted results
of these natural processes are shown on Figure 5-1 which
presents the decline in TCEA concentration at the pro-
duction wells as a function of time. The anticipated
TCEA concentration profiles in the well field as a
function of time are shown on Figures 5-2, 3, and 4 for
the future years 1, 5, and 10, respectively, beyond the
sampling results of December 1986.
Restricting access to the aquifer is recommended because
of the predicted presence of contamination which may
exceed ARARs at some locations. This situation is pre-
dicted to continue for approximately 4 years. The
inclusion of monitoring and re-evaluation activities in
this alternative satisfies regulatory concerns; however,
as an institutional issue, it is recommended that the
State, County or local government use their respective
authorities to restrict access to the aquifer until
ARAR~ are met in the aquifer.
The components and analyses proposed under the no action
alternative are considered to be straight forward,
accurate and highly reliable in determining conditions
at the locations of the sampling. However, the histori-
-------
-11-
predicting aquifer behavior, and the size of the study
area ~Jl indicate that the monitoring system cannot
guarantee that no contaminants could arrive at a produc-
tion well without warning. The continuation of aquifer
evaluation using the model' in conjunction with an extensive
monitoring program helps lessen-that concern. The scope
of this program incorporates a total of 37 wells into a
monitoring network. For the first two years of monitoring,
four quarterly rounds will be taken at each of these wells.
In subsequent years, it is anticipated that quarterly
sampling at a reduced number of wells and with fewer
analytical parameters would be performed. Results of the
first two years of monitoring will be utilized to verify,
or modify, the aquifer performance model.
This program is sufficiently comprehensive to track the
existing TCEA plume, provide water quality results vs
time and space for comparison to model predictions,-and
act as an early warning system for the Suffern and
Spring Valley well fields.
~
No long-term adverse impacts on air, soil or surface
water are anticipated from this alternative. The
ground water quality will improve and reach a point
within 10 to 15 years where no impact will be definable.
A present worth evaluation of the estimated costs for
Alternative No.1 is presented in Table 5-2. As can be
seen from the table, this no action alternative may have
significant costs; the present worth amounts to $311,000.
Alternative No.2 - Treat Suffern Public
Water Supply With the Existing Spray Aeration System
The rehabilitated spray aeration system would not be as
effective as packed tower aeration for removing volatile'
organic compounds. Low concentrations of TCEA (zero to
about 10 ug/L) are predicted by the model to be present
in the Suffern public supply wells after December 31,
1988. If the existing spray aeration system is only
60% effective for VOC removal, 'then it would be expected
to achieve effluent quality conforming to the most
stringent ARARs.
No significant health hazards are posed by the release
-------
-12-
The contaminant characteristics of the aquifer as a
function of time will be similar to Alternative No.1.
Therefore, it will be necessary to restrict access to
the aquifer because 'contaminant levels may exceed ARARs
at some locations. This situation is predicted to
continue for approximat~ly 4 years.
Alternative No.2 is not required to be implemented in
order to meet ARARs a~he well head at any future
time, based on the modeling discussed previously.
Combined with a program of strict aquifer use, spray
aeration has the potential of reducing the levels of
VOCs to a level which approaches NYSDEC guidance values.
The reduction in the exposures to carcinogenic volatile
organic Compounds would not be as significant as could be
expected with packed tower aeration technology, but is
Comparable considering the low threat presented by the
contaminants found in the water supply.
The contaminant characteristics in the aquifer are entirely
analagous to those described under Alternative NO.1, :
no action. ~
Although the rehabilitated system will not be normally
operated in a recycle flow mode, this capability will be
available as an emergency treatment option. If higher
levels of VOCs are detected in the supply wells than' pre-
dicted by the Suffern Aquifer Model, then the Suffern Water
Department will have some flexibility to raise the removal
rate of VOCs, albeit at a lower system flow rate.
-.
The rehabilitated system is anticipated to be easily instal-
led and operated in the area occupied by the eXisting spray
aeration system. The time to establish normal operation is
expected to be about six months. With the exception of the
no action alternative, the time to initiate ground water
treatment is the shortest for Alternative No.2.
No long-term adverse impacts on soil or surface water are
anticipated from this alternative. Groundwater quality
will improve and reach a point within la to 15 years where
no impact will be definable.
Operation of the rehabilitated spray aeration system at
2,650 gpm could be expected to initially cause an emis-
sion of the order of 0.1 lb/hr of volatile organic vapors
into the air; this would decrease with time. The rate
of emission of VOCs from the spray aeration system is
expected to be lower than the Acceptable Ambient Levels
(AALs) of the contaminants of concern (l,l,l-TCEA and
its degradation by-products), and would not represent
-------
-13-
Capital costs and operation and maintenance costs to
complete Alternative No.2 are presented in Table 5-2;
total present worth amounts to $1,260,000.
Alternative No.3 - Treat Suffern Public Water
Supply wlth Packed Tower Aeration
The technologies proposed in this alternative conform to
the preferences of CERCLA for remedial actions that use
treatment to permanently' and significantly reduce the
volume, toxicity, or mobility of hazardous substances.
Utilization of packed tower aeration to remove VOCs
from ground water is a permanent solution in that the
technology significantly reduces the potential exposure
to and toxicity of the VOCs. The low inhalation hazard
caused by the emission of VOCs from the treated ground
water is considered less significant than the hazards
posed by ingesting contaminated ground water or the
dermal contact route of exposure.
Alternative No.3 is not required in order to meet ARARs ~
at the well head at any future time, based on the model-
ing and assumptions discussed previously. It does have
the potential of reducing the levels of VOCs to the most
stringent NYS guidance values.
There is a high degree of confidence that effective per-
formance will be attained treating the Suffern water
supply, as has been done at other similar sites. The
physical characterist.ics of the contaminants of concern
in the ground water are suitable to separation by air
stripping.
- .
The packed tow~r aeration systems can be designed for
flexibility, durability and ease of operation. Two
packed towers are provided for parallel independent
operation. Maintenance can therefore be performed on.
each system. Also, if the influent concentration exceeds
the "worst case" design basis, the system can be re-
aligned to treat a reduced flo~ rate with a series
packed tower operation (rather than parallel).
The packed towers are dependent on the effectiveness of
the existing manganese removal treatment system; at
high manganese levels, fouling of the tower packing
materials may occur.
The packed tower aeration system is anticipated to be
easily installed in the area occupied by the current
spray aeration system. The time required for pilot
plant testing (if required), and the subsequent design,
installation, and startup of the field facility is antici-
-------
-14-
The contaminant characteristics of. the aquifer as a
function of time will be similar to Alte~native No. t.
Therefore, it will be necessary to restrict access to
the aquifer because contaminant levels may exceed
ARARs at some locations. This situation is predicted
to continue for approximately 4 years.
During the time when the new packed tower aeration facility
is being constructed, the Water Department will be unable
to use its aeration sys~em in the event of heightened
contamination. The Suffern Public Water Supply System
is currently interconnected, at four locations, with
the Spring Valley Water Company. The latter has indicated
that .they are ca~able of providing water to Suffern on
an emergency basls. Determining the length of time
that Spring Valley could provide water to Suffern would
require additional study. Since the Suffern Water
Department does not currently use the existing spray
aeration facility to continuously treat the public.
water supply, the temporary loss of this facility would: ;
not be expected to pose a greater threat to publlC ~
health than currently exists. Thus, though it is a
concern that the existing spray aeration system would
be out of service during implementation, it is not an
overriding negative factor.
No long-term adverse impacts on air, soil or surface
water are anticipated from this alternative. The ground
water quality will im~rove and reach a ~oint within 10
to- 15 years where no lmpact will be deflnable.
Operation of two packed towers at the maximum design ca-
pacity would cause the emission of less than 1.0 lb/hr
of volatile organic vapors into the air. The Acceptable
Ambient Levels (AALs) from the "New York State Air
Guide-I: Guidelines for the Control of Toxic Air Con-
taminants" (NYSDEC, Division of Air Resources, July
1986 printing) were compared to the estimated air
concentrations for the contaminants of concern. Since
none of the VOCs released will exceed its AAL at any
receptor in the area, no air emission control should be
necessary.
The present worth of capital costs and operations and
maintenance (O&M) is $1,392,000. Since it was assumed,
based on aquifer modeling results, that Alternative No.
3 would require 15 years to complete, the present worth
costs of operations and maintenance are more than twice
the magnitude of the capital costs. The costs to replace
capital equipment is relatively small in comparison to
-------
-15-
Alternative No.4 - Plume Containment b~ Extraction at
the POInt of MaxImum ContamInatIon: Pac ed Tower Aera-
tion, and Discharge to the" Ramapo River.
This alternative would be expected to achieve effluent
quality conforming to the most stringent standards. Packed
tower aeration of the contamination ground water would
constitute a permanent removal of VOCs from the aguifer.
The toxicity and volume of VOCs would be reduced In the
aquifer. The stripped compounds should not cause public
health risks in the atmosphere. Mobility of compounds
within the aquifer would be sharply reduced by the recovery
of contaminated ground water.
Alternative No.4 is not required to be implemented in
order to meet ARARs ~the well head at any,time in the
future.
For Alternative No.4, the estimated time required to ~
reduce or remove contamination to below ARARs in the aqui-
fer is estimated at one year from inception of operationr-
Since ground water would be extracted at points of maximum.
concentration, the most complete and rapid remediation of
aquifer contamination would be attained.
As discussed for Alternative 3, system effectiveness can be
expected to be maintained as long as significant fouling of
tower packing does not occur. For a system operational time
of one year it is not expected that packing change will
be required.
Since well water characteristics at the proposed recovery
well locations are not known, it is recommended that the -
pilot study be conducted for at least four weeks before
design is initiated. The pilot study will determine if
pretreatment of raw well water is required to remove
iron and/or manganese prior to aeration. The time from
start of testing to beginning of operations is anticipated
-------
-16-
Several institutional factors would need to be considered
in the implementation of this alternative. First, an
entity to operate the ground water treatment system and
oversee compliance with NPDES discharge permit standards
would need to be designated or created. Second, real
property or temporary construction rights would have to
be obtained for the land required to install wells and
construct the treatment systems. Furthermore, land
would need to be acquired or a right-of-way obtained to
permit the installation Df discharge piping to the
Ramapo River on both the west and east sides of the
river. Any potential conflicts of this alternative
with existing aquifer management would require resolution.
On the plus side, little or no aquifer restriction
would be required due to the short cleanup time.
No long-term adverse impacts on soil or surface water
are anticipated from this alternative. Ground water
quality will improve and will essentially meet ARARs
approximately one year after commencement of extraction-
operations. Emission of VOCs into the atmosphere will -
be similar to Alternative NO.3, of the order of 0.1
Ib/hr, and as such would not represent a significant
adverse impact on air quality.
The present worth of capital costs and operation and
maintenance (O&M) to complete Alternative No. 4 is
$817,000. This is a point of departure alternative
since it accomplishes site cleanup in the shortest time
frame. Costs to conduct this remedial action are
relatively low: the alternative is completed in one
year and high costs to operate finished water booster
pumps are avoided since the water is treated and gravity
fed to the Ramapo River.
..
~
- -
The total costs for this alternative are considerably
lowered by making the assumption that after one year,
much of the high cost equipment will be in good working
order, and have a significant resale value as used
equipment.
Alternative NO.6 - Plume Diversion b Suffern Well
Nos. 3 and 4: Treatment by Packed Tower Aeration an
Discharge to Suffern System
The remedial technology for use in Alternative No.6 was
designed to produce an effluent quality conforming to the
most stringent standards. The degree of reduction in
mobility, toxicity, and volume afforded by Alternative
-------
-17-
Alternaiive No.6 is not re~uired to be implemented in
order to meet ARARs at, the well head at any time in the
future.
The estimated time required to reduce or remove contami-
nation to below ARARs in the aquifer is estimated to be
four years.' Figure 5-6 presents the TCEA concentration
profile at the end of 4 years of operation; the peak value
is 2 ppb, corresponding 'to a DCE value of .04. This
time period is longer than that of Alternative No.4,
for which a one year project duration is estimated, but
$horter than that of Alternative No.3, for which a
fifteen-year project life is forecast. Because ground
water wquld be pumped from the projected outer edge of
the plume, a less complete remediation of overall aquifer
contamination would be achieved in this alternative.
The packed towers are dependent on the effectiveness of. ;
the existing manganese removal system; at high manganese;
levels, fouling of the tower packing may occur. ~
Since well water characteristics at the proposed recovery-
well locations are not known, it is recommended that at
least a four week pilot study be conducted before design
is initiated. The pilot study will determine if pre-
treatment of raw well water is required to remove iron
and/or manganese prior to aeration. The time from start
of testing to beginning of operations is anticipated to
be about eighteen months. '
Some disruption of existing systems would ensue during
stri~per packed tower aeration system tie-in. Dis-
ruptlons to the distribution system can be minimized by
accumulating sufficient water in elevated storage to
meet the expected demand during tie-in. Because two
packed towers would be installed, a portion of the
water demand could be treated by one unit while the
other unit was being installed and connected into the
system.
Restricting access to the aquifer is required because of
the predicted presence of contamination which may exceed
ARARs at some location. This situation is predicted to
continue for approximately 2 years.
No long-term adverse impacts on soil or surface water
are anticipated from this alternative. Ground water
-------
- .
-18-
approximately two years after commencement of treatment
operations. Emission of VOCs into the atmosphere will
be of the order of 0.1 lb/hr, and would not represent
a significant adverse impact on air quality.
The total present worth of capital costs and operations
and maintenance costs (O&M) is $840,000. The capital
costs to implement Alternative No. 6 are the same as
those required for Alternative No.3. However, the
annual O&M costs for Alternative No.6 are slightly
higher than for Alternative No.3 because the energy
requirements to operate the blower required for Alterna-
tive.No. 6 are higher.
The present worth costs for Alternative No.6 are less than
those of Alternative No.3 since the period of performance
is only 4 years for Alternative No.6 while it is 15 years
for Alternative No.3. The present worth costs for Alte~na-
tive No.6 are greater than those of Alternative No.1 (the
no action alternative) and Alternative No.4. . :
~
VI.
SELECTED REMEDY
A - Description
The no action alternative would provide for no active remedial
measures. No ground water pumping, diversion, treatment or
other activity is contemplated. Management and use of the
Ramapo River Valley aquifer will continue in its present manner,
including major withdrawals by the Spring Valley Water Co.
and Suffern Village. Monitoring of the ground water is the
only activity included.
In as much as no ARARs are predicted to be exceeded at the
existing ground water removal locations, the requirements
of CERCLA cleanup standards are intrinsically met without
further action.
With respect to the goal of management of migration, no
active effort is directed to this objective. Only natural
processes would act to permanently reduce the toxicity
and/or mObility of contaminants. Toxic, mobile contaminants
will remain in some locations in the aquifer for five
years. Accordingly, there is the need to reasonably include
restricting access to the aquifer because of the predicted
presence of contamination which may exceed ARAR standards
at some locations. This situation is predicted to continue
until approximately model year 4. Therefore, it is recom-
mended that the State, County and local governments exercise
-------
. 0
- -
-19-
aquifer until ARARs are met in the aquifer. The inclusion
of monitoring and re-evaluation activities in this alterna-
tive does help satisfy regulatory concerns. The scope of
this program incorporates a total of 37 wells into a moni-
toring network. For the first two years of monitoring, four
quarterly rounds will be taken at each of these wells. In
subsequent years, it is anticipated that quarterly sampling
at a reduced number of wells and with fewer analytical
parameters would be performed. Results of the first two
years of monitoring will be utilized to verify, or modify
the aquifer performance model.
This program is sufficiently comprehensive to track the
existing TCEA plume, provide water quality results vs time
and space- for comparison to model predictions and act as an
early warning system for the Suffern and Spring Valley well
fields.
The source for the contaminants of concern presumably origi-. ;
nated prior to 1978 from the operations of Tempcon CorporatioQ.
Shortly thereafter the activities causing the problem were ~
discontinued. Contamination has spread beyond the initial
"point source"; therefore, no attempt at source control is
feasible.
B - Statutory Determinations
As described herein, and with the assumption that model
predictions of contaminant concentration and time profile
prove to be valid, no action is required to be protective of
human health and the environment.
The ARARs that have been considered are presented in Table
5-1. For a detailed review of ARARs, refer to the Feasibility
Stud„, Section 1.3. No waivers of other Federal and State
laws have been invoked.
By reference to Table 5-2, Summary of the Evaluation of
Alternatives, it can be seen that this alternative has the
lowest present worth; in consideration of the noneconomic
criteria as well, it obviously is the most cost-effective
solution.
Further, with respect to other alternatives embodying the
preference for treatment, the absence of threat to human
health and the environment has led to the conclusion that
treatment is unnecessary. Also, in consideration of utili-
zation of financial resources, treatment is not desirable
-------
-20-
-------
-21-
N
£/
I
, t
"
'\:"
\',99
8-21_) j
e_22/' i
. " 100
E. j!0
C. .jJ.8-19
8-23j f .8-20
i !
I ;/;j~ W,i,
(r/'.O:-I
~I t H
~J" l".J 4 . - H
.... 0
" " I
~ I f ~2
\\ ..p
" ...
e)) . - 03
/,1
lei
,;" I"
tI/ I
. ~!(.
tlf(
~ J j
I
o
r
/600
-J.
800
,
F E £ T
LEGEND
01- Production W'II.:
Suff.rn w.n. .',2,3 & ..
8-19 Spring Valley Well.. 88 &
. -Spring Vaney Test Well.
.A-ERM Monitoring Well.
. -USGS - Obl.rvation Well
OW-I
100 -
~
.L
J(
.
LOCATIONS OF WELLS
SUFFERN WELLfI'lELD
ROC I( LA N D CTT, NY
[3B ~RM.:N~;th~Qst.
Flgur.
1-,2,
-------
WEU"'1
'\
320
280 -
FIGURE Z -I
AVERAGE MONTUL Y TCEA CONCENTRATIONS
SUFFERN WELLS
NOVEMBER 1978 - FEBRUARY 1987
1
.-
m
0..
0..
-
I
I .
! ........ l\\j\
I I ,\
I \ I ~
/ '\ '1; t"
: /.r!'
; I f\. \ if! I! /1
! II' r. I', I ,. i
/'" f. i V \ : : II i i
I : " .. . I !
I ! " : J I' .~ WELL "'2 : .. i
I I"" 'II . ! ;"" :
: ',. \ " I ; i 'l :
I:: " 1 1\.1: : 'l/'1 ! ! ! "") I
I i ~ ~ ,'\v' , I. y! I : i ;'",
'. , , ' .. , "
,: ...,.... , I',: i : I:. ...
I : .,' '-"', 'II ;,:, ! i i ! i ,/ \
'I : r . .~ 1, , 'IJ " \ I I I: : I: 'I ./..
. " ~ .,. I. . I . . '.
: :, , " , I I , ,'. , ' ,.' "
. . , I , , , , '. """ ,
'i!! 'I: A ~J/'l ~ '\ \! i ~/' \\,'., ~~\",,.---_.:-.,:-...~
: . : I \II ,..., 'I f ,. .: ~ \ ",.'" ",
J ;. . II.)" .. "I: ,..,,,, \
' : '" h '- ,; "', /\ J\ /
: : '~ \, :: : \/ ',,-.--.. .. --'-... \, - ~. V'"
, " 'I. . '" , ,
" WELl... ~ .; I '~'" r-
i . r.' ~J~'._c-::'v:.:"",'.-:,;;d.
6 , I J 6 , " J , , J 6. , 11 J 6 , 11 J 6 , 11 ). , , 11
1980 1981 I 83 . 1984 1985 19136 .. 1987
I
"-'
l-."j'
I
2..0
200
fJ)
z
o
;::
c(
0:
...
Z
1&.1
o
Z
o
o
c(
1&.1
o
...
LEGEND
180
-----
Well * 1
WEll 4> 2
W'=ll .,:.\
'WEll ",.
PERIODS DURINQ WHICH
WEll WAS NOT
MONITORED,
-------
.................. :..
120
80
40
TIME'
r "'"
-------
~
a
a
cr::
m
z
cr::
::>
m
,-1
'-1
:I:
Tp-2
'\
~
Parking Lot
Tempcon Building
Wall
Tree
882
Tp-3
I
~
o I
~,
883
Approximate limits of
1979 Remedial Activity
------~
/" --"
. . ,
I I
I I
I ,
I I
" ,
, I
L - - - - / ,
-------
~
T
I
I
j
I
:
I
I
I
>-
~
=>
a::
::I:
I-
IJJ
l-
t"!
CI)
~
a::
o
>-
3:
LLJ
Z
Tp 12 EJ
Tp8 ~
E 2 .
E 1 ..
Tp 10 [!J
Tp 11 EI
-24-
LEGEND
\ CONTOUR LINE
'" TCEA CONCENTRATIONS
IN SOIL
Tp 6 SOIL TEST PIT
-Tp 2
.
,
[J Tp 5
...
60 Ppb
....
......
, . Tp 7 ... ... 100 Ppb
,
,
,
, 200 PPb
o
I
SCALE
25'
t
50'
1
TEST PIT LOCATIONS -E - SITE
VILLAGE OF SUFFERN
NEW YORK 12/15-16-17/86
FIGURE Z-3
-------
o . .
N
4
-25-
~H
- L EGEND-
@ Production Well
o Monitoring Well
2 TCEA ConCenlrQlion (uQ/I)
's: Confou.r 0' TCEA-
..... Concent\otion IUQ/I)
U Und. rected
..
TCEA CONCENTRAT.ION MAP
(DEPTH AVERAGED BY WELL CLUSTERS
BASED ON SAMPLE ROUND OF 10-B6)
SUFFERN W~LL FIELD ROCKLAND CITY, N.Y.
~-
800
.
F E £ T
/600
I
.u
L
UK
.
FIGURE Z-4
-------
-26-
N
4
. .
A
.
- .
G>
3
o
~
800
+-
F £ £ T
/600
J
- L CGCND-
@ Produetlon WI/I'
. Monitoring Will
2 TC EA Concentration (uQ/I)
's:. Con to u r 0' TeE A-
" Concentrotion (uO/IJ
,
.N
..
. - ECONO-TRUCK BODY
2 L
I J(
.
TCEA CONCENTRATION MAP
(DEPTH AVERAGED BY WELL CLUSTERS
BASED oN SAMPLE ROUND OF 12-86)
SUFFERN WELL FIELD RO(:KLAND CITY~ N.Y.
FIGURE Z-S
-------
- - "'. .. '--1- -,
I. '~I i I I' ,
YE.~~~ ~).11J.r.~~l~t! !: ~ : i
'\
.1
I . .
I r 1~
I I ' ,
I I
. . . .
. ,- , . ... I
I :.!! I',: 'II
! . .. ,. I' ;
1---.--, 'I
: i i i I i/ I . . . - .
, " ,
. I :-r :rT NO ~~~:nON I.
: . . : (NO RMAt OPER~ TION) I
2G- _. . . 'I I. .
19- I: :: i I' , I: I; :;!,;" j
..' ~ I i II ;::; I ,
10- :: ..1 - -- t I p'i - . - . - . .
17- ; ~ ! I l
I I. I .
:1 6- :f '1-; . I - ~ . - - - - - - - - - - - -
15- ; i -.
I
~ ~ 4- :T ~ I SU.FFERtI
~ ~3- ~; . WE~~J~
; :82-Ir-- 1\ }1l
2 '11- ; ~ . . . - ~. .
t-'
~ 1G- .. I - - I
~ 9-:' : j
i
I
. - - .
- -
. -
.. _... ~'--. - -
. - - - - - -
-
...+ -'-
. -.
I
. .
- . ..
. -
- - - -. --
-
- - .
. - -.
-
-" iii-t" ,
I'! I ill
-1- - - - -- -, f- --,_.. - -
. I
- - - - --I 1.
ERM-NORTHEAST
RI/FS OF THE SUFFERN WELL FIELD
ROCKLAND COUNTY. NEW YORK
ALTERNATIVE 1:
NO REMEDIAL ACTION
SIMULATED TCEA CONCENTRATION IN
WELLS 1,3,4 AND 100
- - - -
-
- .
. -
. .
. -
- - - - -.
. - .-
. .
-
. - - - - - - - - . .
. . .
- .
, - - ". . - -
. - - - . -
- .
- - .
. .
- . .
... - .
-
- -
.. - - -.
- .
I
i
I I
I
! I
- - p - . -
-
- . - . -
- --
- . '-
.. -.
- - -
-
. . - - - - .
- -..
r
- .
- - - -
- . - -
. .
-
r
. -
- - . - .
W ., I
~ O-r " .- -.- ,.\,
. S 7:- ~ i - - - :. I,!
ct6-~~ - I~
. I .,. ..-
~ 5 - : ! ~ ii, , 'SUFFERN
t- 4 - ~~J ~~m' '~, WE]LillIL l'
I' I ! , 1 -
3- : .!, !
.: '~SVWC 1\
2- ~ \~~~L-10~ I SUFFERN' I J J',
1- . "$WII,,!II .! W~L~31 I ! Iii ~I-L-,' ,: ~~tr ~k +1 I
0- .-. .-...J iT- ,. _r! ----r--l-----" -0 . .~.I .... I' J .- mRt -- - . .
. - .1 i~i~~Jjl m~~~: m L_~A~13J .t~~~~~ 11 l : ;~-~~~I;~11 i 1~~~2ij! h~~~ii, .
. - - - . . .
... ..
_. - - - -
. .
. .
- - - -
- .
. -
. .
.
.1
- -
l!
I
. -.
I.
~ I . .
I
I
:-
I
II
-
I
I
I
I
I
-
-
I
I
1
I' I
II:
tiLL
II! Ii;
,k"
'I Iii;!;
i~-
'II I.,:
! !! i:.' :
'~T ti,--I
I+r! t'~;:
I I . I
j. . ;
.!3,;~
.1' I : I.
: 'I,
..~..
I
t~
-J
I
"
c;)
c
:u
m
LEGGETTE, B~ASHEARS & GRAHAM. INC.
Ln
I
-------
6f'"
~.
;f.'/
41/'
. PIAtt CONCINTltAnON . "PGlL
.-
NOTU: ALn"NAT1VI ., . NO-ACTION
AU. IU"LY WIUI O~UTl AI NO"MA&,
1.EGGETTE. BRASHEARS & GRAHAM. 'Ne.
'12 DANBURY ROAD
WlL TON, CONNECTICUT 0881.,
o 100
E3==:l
ICAUIN nIT
-28-
tlOO
-1
~IC UI'IE
5-2
1
LEGEND
I
It
I
r-"
AOUI~E~ BOUNDAR.,.
:::'--. SURFAC! WATER
~ WEIR
e. PRoouC'nON WELL
. 08SERVAnON WELL
..r- MOO!I. eoUNOARY
. '-'$Ol"l.nH 0' EQUAl. 'T1:U
I' CONCENTRATION IN jJG/1.
...
ERM-NORTHEAST
RifFS OF THE SUFFERN WEI.L FIEL.D
ROCKLAND COUNTY, NEW YORI(
AI.TE~NAnvl 1
IIAoIUUTEO TCU CONCENTRAtiON
AT THE END 0' YUR ,
-------
".
I
~" .Ta-1S
\'iPW-2
TB-'\, 19
T8-'h) )
TIW"CON 1f.T8-n
O. T8-U.
a .l '8-11
E. 1~100
C. ..
., T8-,.
'8-23./" .'8-20
. J.
I. i/WE'f/4
~REG.08S.
l ."
f.J
\.
~~~..~ 0
o;V
~I
1;/
~.
-
. 'IAIt CONCINTllla.T10M -, JlO/L
NOTU: A.L.T'lItNATTW".' . NO-AC1ION
AL.L au"",y WILU ONAATI AI NOIt~
" L.EGGETTE. BRASHEARS & GRAHAM, INe.
12 DANBURY ROAD
WILTON, CONNECT1CUT 08887
.N
.L
.Ie
.
E3
ICAI.I IN nET
8..
I
J
-29-
,.0'
j
I
N
l
'IQ U R E
5-3
LEGEND
r-'
AQUI'E.. OOUfoIOAAY
::-"~ SURFACE WATER
~ WEIR
CD
'ROOUCT'!OJj WELl.
OBSERVATION WELL
.
~ MOon BOUNDARY
/ lSolII.n~ 0' EOUAL T'CU
,,' COHCENTRATION IN IJQ/I.
..
ERM-NORTHEAST
RI/FS OF THE SUFFERN WEL.L. FinO
ROCKLAND COUNTY, NEW YORK
ALTtIlN"nVl ,
l'IoIUI.AT!D 'CEA CONCEHTItATlON
AT THE END 01' TEAIt .
-------
-30-
.-_._0.__.. -
~IG U R E
)-4
1
LEGEND
Ae
I I
~\. eTe-,1
T8~~:.W-Z
T8-2'~ )
TiEM'CON II TI."
o el TI.Z!l' 1;1.,.
I. {~IOO
c. ..
I TI."
TI.U~/' .TI-2O
. I.
i ~ )JWIIIt
~~IQ,O".
If .H
/. Je" .0
, 0'
~{ °2
'~Me
.,
. Ii
'1/
41.
I
It
I
r-'
AOUIFER BOUNOARY
~.::: SURFACE WATER
~ WEIR
~
PROOUCTION wELL
OBSERVATION WELL
.
..r- MODEL BOUNDARY
O~ UMIT 0' Tello 'LUMI
~
eN
eL
..
.IC
. !tUIC CONCINTltATtON ., JlGlL
NOns: ALnltN41tva.,. No-AC'nOII
A&.L. IU''''" WILLa O"ftATI AI NOItMA&,
EFlM-NOFlTHEAST
FlIIFS OF THE SUFFERN WELL FIEI.O
ROCKLAND COUNTY, NEW YORI<
I.EGGETTE. BRASHEARS & GRAHAM, INC.
12 DANBURY FlOAD
~LTON, CONNEC~CUT 08887
.
a
SC4LIIN P'ln
100
I
J
1100
I
A LnltNA1tVI ,
"MUUTED TCU. COHCIHTRAnOIil
AT TNI IHD 0' TIA" '0
-------
A.
I
(, .T8-15
\\iPW-2
T8-1I\' U
T8~2h) )
TlM~CON ItT8-17
O. T8-22,
8 .J T8-'8
E. 1~100
C. .
.,' T8-19
T8- 23 /' ...
...-20
, .
o . J.
I. i.: lWEIR
. ~REC,08S.
T .H
Ji "'0
A' . Q'
\(~ u .,
I;)' .,
1/,/
~f/
-1'
-'
. 'UIC CONCINTIIATI08I -. ~Q/L
-31-
.N
.1.
.Ie
NOTaia AI.TIRNAT1YI 4, fl\UM. CONTAINM.NT
INURCCPTOR WII.L8 'UM"NO CONnNUOU81.Y
WIl.l. AI1400 ON
WELL 8: tOOO ON
LEGGETTE. BRASHEARS & GRAHAM, INC.
72 DANBURY ROAD.
WILTON, CONNECTICUT 06897
o 800
E::::EJ
SCALI IN fEET
I
I
r--'
"aURE
5-5
LeGEND
AOUIFER 80UNDARY
-=:.:::= SURFACE WATER
I:::::) WEIR
~
PRODUCTION WEl.L
08SERVATION WELL
~I
o
/
...
A
.
~'OD!I. !lOUNDARY
raO'LiTH 0' laUAL TCU
CONCINTRAnON IN IJQ/L
INTeRCIPTOR WIU.
..
enM-NORTHEAST
RIIFS OF THE SUFFERN WELL FIELD
ROCKLAND COUNTY, NEW YOqK
1800
I
ALTEnNATIVCt 4
S'MULATtD TCU CONCI!/'C1'AATION
AT THE tND 0' YUR S
-------
",.
. 'lAIC CONCINTRA1'IOM .. .11M
I
,\
. \, -T8-1S
\~pw-Z
TS-II\',' II
TO-Z18) }
TI!MPCON / L TS-17
O-s TS-Z!j'I;S-18
E. /.~IOO
c- .-
I TS-1.
TI-U~/' .T8-Z0
/.
I. JJWEIA
~REG,OIS.
If .H
i /.J 4~1 .N
. ' { CD,
-32-
NOTla~TlRNAT1YI" .w... 1IIYIItIION, WILl. a .. "'''''NO flATU INCRUlIO
"'"III VIA" I
LEGGEne. BRASHEARS & GRAHAM, INe.
72 DANBURY ROAD
Wl1.TON, CONNeCTICUT 08897
.L
0,
.-
.
S
SCALI IN I'1!ET
800
I
J
1800
I
:'
"tQUR! 5-6
LEGEND
I
It
I
~
ACUIFER BOUNDARY
::::::::: SURFACE WATER
<:::::, WE'R
~
PRODUC"ON WELL
OSSERVA"ON WELL.
.
...r- ,",OOlL BOUNDARY
J LIMIT OF TelA PLUM!!
/,,0
~
ERM-NORTHEAST
RI/FS OF THE SUFFERN WELL FIELD
ROCKLAND COUNTY, New YORI(
ALTtRN"'T1V8 .
""'ULATI!D TCEA CONCEHTRAT1ON
AT THE END 0,. YEAR 8
-------
'\
TABLE 2-1
WATER QUALITY DATA - OCTOBER 1986
SAtIU Rn1Ir 1 1 1 1 II 1 1 III I
1 1,1,1 '1tD. 1 1,1 lID 1 1,2 IXD 1 1,11XE 1'lWINEa ~ IAHl'IKI«IQIDII(M:CIlftRllEAD:SJntm:Zll£
A.-1 1 V 1 IV 1 U 1 U 1 U 1 U 1 M/A 1 M/A Ilf/A 1M/A IN/A IN/A
B-1 1 V 1 V 1 U 1 U 1 U 1 U 1 N/A . M/A IN/A IN/A IN/A IN/A
B-2 . '7 . ~ 1 U 1 U I U 1 8ft. 1 M/A . M/A IN/A 1M/A IN/A IN/A
B-3 . V . V 1 U 1 U 1 U 1 U 1 H/A '. M/A IN/A IN/A :H/A IN/A
B-22 . J6 1 ~ 1 U 1 U 1 U . U IN/A I N/A Ilf/A IN/A IN/A IN/A
Iha) 1 V 1 U 1 U 1 U 1 S 1 U I M/A 1 N/A IN/A IN/A IN/A IN/A
B-19 . V . V I U 1 0 1 U 1 U 1 M/A . M/A IN/A IN/A IN/A IN/A
B-21 . U 1 0 . U 1 0 1 U . 9 1 M/A 1 N/A IN/A IN/A IN/A IN/A
~ 1 22 . 6 1 U 1 U 1 U 1 U . M/A I N/A IN/A Ilf/A :H/A :H/A
~1 1 0 1 V 1 U . U 1 U 1 U 1 N/A 1 H/A IN/A IN/A :H/A :N/A
C-2 1 V 1 V, 1 0 1 U ' 1 U . U 1 N/A . H/A IN/A :H/A IN/A IN/A
&-1 1 1) 1 S 1 U 1 U . U 1 0 IN/A I H/A IN/A IN/A IN/A IN/A
E-2 1 7fJJ 1 140 1 7 I 86 I U I U 1 M/A . M/A :H/A Ilf/A IN/A IN/A
1,.1 1 U 1 0 1 U 1 U 1 S 1 U I H/A . .D5 IN/A aN/A IN/A IN/A
1,.1 9/25/86 I 8 1 V 1 U 1 U I U 1 U 1 'Z1 I ~ I 111 I ~ I U a 82
K-1 I U 1 V 1 U I U . U 1 U II/A I I/A IN/A :N/A IN/A aN/A
K-2 1 V I U 1 U I 0 1 U I U 1 K/A 1 H/A IN/A IN/A IN/A aN/A
8-1 1 U I 1 U 1 U 1 U 1 U 1 U 1 M/A I H/A IN/A' aN/A IN/A IN/A I
H-2 I U 1 U 1 U 1 U 1 U I 0 I K/A I H/A Ilf/A IN/A aN/A IN/A w
w
HID \tIL 11 1 6 1 U 1 U I 0 1 U I U IN/A I N/A IN/A IN/A IN/A :N/A' I
HID ww. Il I S I U 1 U 1 0 1 U I U IN/A I H/A IN/A :H/A IN/A :N/A
HID \rI1L IJ . U 1 U 1 U I 0 1 U I U IN/A . M/A IN/A IN/A IN/A IN/A
HID WElL 14 I ' 12 1 U 1 U 1 U . U 1 U . M/A . HlA IN/A IN/A :N/A :N/A
HID \tIL 14 9/25/861 V 1 U 1 U I U . 8ft. 1 U 1 U . U '21 1211491 0
B-1 1 0 1 U 1 U . U 1 U 1 U . M/A . N/A IN/A IN/A IN/A IN/A
B-2 . 13 1 U 1 U 1 U 1 U 1 0 . M/A . H/A IN/A IN/A IN/A IN/A
1-1 . 53 1 8 1 U 1 U 1 U I U 1 N/A . M/A Ilf/A IN/A :N/A IN/A
1-2 . 'R . 2 . U 1 U I U 1 U . N/A . N/A IN/A :H/A IN/A IN/A
1-3 .. 19 1 lH«, 1 U 1 U 1 0 I U . N/A . N/A IN/A IN/A IN/A :N/A
J-1 . 19 1 U 1 U 1 0 .U I 0 I N/A . HlA IK/A IN/A IN/A IN/A
J-2 1 17 1 U 1 U 1 U . U 1 U . N/A . N/A IN/A :H/A :H/A IN/A
J-3 . u 1 U I U 1 0 1 U 1 U . N/A I N/A 8N/A IN/A IN/A IN/A
K.-1 . U . U . 0 1 0 I U 1 0 . N/A . H/A IN/A :N/A IN/A IN/A
ml1 . u 1 U 1 U 1 U . 0 1 U . N/A 8 N/A :N/A IN/A IN/A IN/A '
mil . u 1 U 1 U . U I 0 1 U . N/A 8 N/A :N/A 8N/A 8N/A :N/A
lIB 81 . 0' I U . U 1 U I 0 I' 0 . NlA'- . N/A IN/A :N/A :H/A :N/A
~ Iffi I 0 1 U . U . U I 0 1 0 I N/A 8 N/A 8N/A :N/A :N/A :N/A
~ 8100 . 'Z1 . 6 1 U 1 U , U 1 U 1 N/A . N/A :N/A :N/A :H/A :N/A
'DUP IIAtK 10/3/86 I U . U . 0 1 U . U 1 U 1 N/A . N/A :N/A :N/A :N/A :N/A
'IRIP IJ..AH{ 10/6IPb. u I U 1 0 I 0 . U I U 1 NlA . N/A IN/A IN/A :H/A :N/A
H1IE: AlL VALmB ~ IS tC/L r ,- '...
t£rAI1) RESI.LTS HOt 9/25/Pb HmIU'1Y RIIDrAH1' :rAN
Bia.: ~ HIHDUI RmRl'OO u.vns
U: ltu:w;WJ
-------
'\
TABLE 2-2
WATER QUALITY DATA - DECEMBER 1986
SAHPI.E fill1ll' . 'REA . 1,1-lD'A . 1,2 IXZ\ . 1IZ . 1,11XZ 1'DW6 1,2-lXE1 ~ IEIH!L ~I '1WJmE I 'IRIOIl.lmFL- I
I 1 1 1 1 1 1 1 1 I tIIDlEnlANE I
I
1.-1 I I 1 1 1 I 1 1 I I I
B-1 I 1 1 1 1 1 1 1 1 I I
B-1 1 4 1 1 1 1 1 1 i 1 1 I I
B-3 1 6 1 .J 1 1 1 1 1 I 1 I I
<'-1 1 1 I 1 1 1 1 1 361 17 1 129 I 1 I
~ 1 1 1 1 1 1 1 1 I' 1 I ,
&-1 1 .351 9 1 1 1 1 1 1 1 1 I 1
&.2 1 ~I 961 S 1 J 1 53 1 . 7 I 1 1 I 1
B-19 . 1 1 1 1 1 1 1 I 1 I I
B-.;D 1 1 1 1 I 1 1 I 1 I I
B-21 I 1 1 1 1 1 1 S 1 1 4 I .
B-22 1 2 1 ~I 1 1 ,I 1 J I 1 9 I I
~ I J 1 9 1 1 I I 1 I I I I
S/JfJ 1 1 1 1 I I I I 1 I I
S/-100 1 12 1 2 1 1 I 1 I I I I I
1-1 I ?SI 12 1 1 I S 1 I I 1 I I
1-2 I 47 I 6 I I I 1 I I I I I
1-3 I 16 1 2 1 1 I 1 1 I I I I I
J-1 1 11 1 ~1 I I I 1 1 I 1 ,I I I
J-2 I 19 1 2 1 I I 1 I I I I I I I
w
J-J I I- 1 1 I I I 1 I I I ~
&-1 1 1 1 1 1 1 I 1 I I
I I
B-.2 1 8 1 1 1 1 I 1 1 1 1 1 I I
8-1 I 1 . 1 I 1 I " I 1 I
I I
H-.2 I 1 I 1 I 1 I I I I I
L-1 I 2 1 1 1 I 1 I I I I I
1-1 I 1 1 I 1 1 1 1 I 1 I I
M-1 I 1 1 1 1 I 1 1 I 1 I 1
M-2 1 2 1 1 1 I 1 1 1 1 I I
SJm1m 111 1 71. 1 1 I 1 1 1 1 I I
mmm 1!2 1 7 I 1 1 I . I I . I I
SIFJmH IIJ 1 1 I I I <1 I I . I 1 I I
mmm 114 1 12 I 1 1 1 I 1 1 I I I I
REG. ~ I <1 I . 1 I 1 I I . I 4 I
mID IIJIH[ JIJ)I I I I I I " I I I 10 I
1 /
mID ILAtI{ 91J)1 I I I I I I I I I 7 I
'DUP IIJIH[ JIJ) I I 1 I I 1 I I I I I
'DUP IUH( 91J) I 1 1 1 1 1 1 1 1 I I
HJlE:
lUH{ S>ACE - tm lImI.irw
AIL a:tmlIRATILm ]H ug/l
n
-------
.,
TARTF. 5-1 '
AIJrmNATIVE 00. 1 - t«>-ACTIOO
APPR>XIHATE cmc:DlmATI(R; OF ~ AT EACH WFFmN m:nJCI'IOO WF.Tl.
vmsus ARM S'l'ANDt\Rm
cnmooNANr
OF~
1,1,1 Tric:hlaroet:hane
(1a'A)
lWIZ OF l\RU'OXimated
CXlDNmATICHi IN YEAR
1 'lHRXGI YEAR 10
IlXJIU
ARAR IJUNKnI; WATm
S'l'ANDt\RQ I~l)
~ S'lRItQm'
NYSDFX: '100
aJItEI.mE I~l)
50
19.6 - 0.1
200
1,1 Did11aroet:hane
(1,1 IX:FA)
1,2 Dichlarcetharie
(1,2 IX:FA) .
9.8 - 0.0052
~o
0.4 - 0.003
5
0.8
1,1 Dic:hlm:oethylene
(1,1 IX:E)
4.3 - 0.024
0.07
7
tOI'ES :
1.
r
m
~
I
:z
i
I
W
V1
I
'!he "raRJ8 ot apprcodmated cxnJentratJ.cns. npresent:s the widest ran:je whicb may ocx:ur in. any of the
productioo wells. '!he raRJ8 was pn!pIE8d by the prooerIt1l'8 dtAnIS~ in the text, usirg the ratios
pteSented in Nates 2 thJ:tujb 6 below.
Based CD a ratio of 0.50 to 1.0 for 1,1, IUA to 1,1,1. '1aA - RI .data, ~'..er 1986, !If B-3 ard Ifi E-2.
2.
3.
Bafied 00 a ratio of 0.02 to 1.0 for 1,2 IUA to 1,1,'n:FA. Based CD ~ 1986 RI data at HW E-2.
Based 00 a ratio of 0.22 to 1.0. for 1,1 DeB to 1,1,1 '1a:A. Based 00 ~..r 1986 RI data at HW E-2.
4.
5.
Based 00 a ratio 0.013 to 1.0 of '1a to 1,1,1 '1aA.
. .
-------
"
TABLE
5-2
SJtWa (F - IMAWAT!at CI' ~
1
I "t} IV1rq IIUI tal 1
' ~......... I .................. . . '''''<=1&,
. I . 1ooou""""" . """" -.. ,(&.11. Gnuu "'''''.,
....,.... "'.... I ...... -- . . ..........,............ '1Irl~ "'<=. AIr. .
. I (au.." I '-""-"". ',",00. n>fflc "" ,
. ...... .... . - .....) . -- ...... to ....... . . .t.......... ur...... '''''''-01 ,
. " . . .... (2). . . . """""J . .
'-'-1 . . . . . , . .
. . .-., ....... . . I . . . . .
'U"""Uoo Ib. ,. .......... . "" I .. '-. - ....,...... " -- . . I . . -. . '.0 DP ..... . """ ~ oot. .-....... $J1,.,,,,,
. . '''''d"" ~ I . I I .1< - -... """"-"'''''''
. I .d4I1 ',. I . . . . ........... . . 00"". ,
'-0-. I . . . . , . ,
. " I . . . . . . ",,"~OO' , .
. I (1)0- ....... . . . ..... Ie.......... . . """- "'''''' .Cepltel """" I ""."'"
. "". .. ..... .........." ". . .. . . .to an.. ...... . . 00"". .0' M ......, I "'."u,
. . ........... . . . '-. ,.0 DP ..... . .- ......, 11.""."'"
. " . . . . . . '''tootW. """U 00 ,
. " I ' . . . I , .... .,..u... """"..
.-.-. . . . I . , . ,
. " . I . . . . . ,
'U_Uoo .... ). -, .. I -- -, I . I ..... Ie.......... . . .... ~ 00' 'Cepltel Coot., I "'.""
'&.rf... """"............. . "" . ... ..... . . ,,,''' . . I . ,... -......... . 0.0 DP..... . """- ....... '0' M Coote. I '.,""
'Wl""", "-"""'" I I ........... . . . -. I ~..... ,,,-,....... 11.>"."",
. """","
' 1_,-""" I . ,
' . " . . . . . . . .
'U"""Uoo .... .. ..... . " . I I . '-" ....., to . . ,
""""'"-I!r "'- It . . ....... -, . . . ....... ".... nel . . _tel """" I "".IW,
.1Ie -,......... . "" , ... '''''''''''''' . . 1 - . " '- _. ... '.0 DP..... "" -- hpooto "'. M Coote. I "'J." " ,
...........- ........... . ............ . . . .- d... to .. I . .So)- ......($ '""Qu),
,-... """" -....... . " . I . . .- "... en . . .- ....... I 81\0.0,
'......... '" n. ..... "... . " , . . . _.. . .
. " , . . . . . , .
.~-. """ ,
. " . . . I . . . ,
,u-oo..., "'..-. . .- -, . . . .an........., . 'Cepltel Coote, I
......, ..... -om ...... ........ ''''''''1''' , . .. -- .......... -. ,.0 DP ..... "" --........ ,0,,, ......, I
,w.u. Ib. ) ... lb.., ........ . 'd4I1ty, . . I ...... .... .. en... , ._~, ....... I
,.... ..... "- --. " , I . . ....... d ..u. .... ,
1 " 1 I I . II'I86d1aJ. JUI1XI608 1 1
1-._. . I . . I 1 1
WDiNATIVE
Coot.
Crt t.cr1a
.
;Alt.emaUve No.2. Tn.t
;&u'rcm I\DUc ~ter ~
;With 'Il1O &1a~ SJn.y
; Aentt.Sai ~1I1.e8
~((,.UIJ,
H7.1111;
t!40,au,
Notes: (1) At h1gtlOIIt et'CocU--. 1.8. with~. thll18Mil. ,
etr1c:1.erq !!!l1lfP'Oedl thtt. ~ fer 'lWe ~ \Ia1uee.
(2) lew1a er anJentzaUcot cL crf7ll'lic CQIpU.111 ~ the
d1Bt.r1luu.at ~ ab-t< edl18w AIWIa (~\iiter
Statde.n1c. , ~ 10 f1nt. CQ)uQ 'Idea- Re&a1a1.caJ Criteria.
r .....
. '
I
W
0\ "'I'
-------
.,.
. 'I-Jew York State Department of Environmental Conservation
50 Wolf Road. Albany, New York 12233. 4011
~.--;"".'
'.' "." :.::1--.1.",
~":~
~....' .
~
Mr. Stephen D. Luftig
Director
Office of Emergency and Remedial Response
U~ S. Environmental Protection Agency,
Region II
26 Federal Plaza
New York,' NY 10278
Thomas C, Jorling
CommiSSioner
SEP 13 1987
Dear Mr. Luftig:
Re:
Suffern Village Well Field Site
Suffern (V), Rockland County
Remedial Investigation/Feasibility Study
The New York: State Department of Environmental Conservation (NYSDEC) has
recently completed a Remedial Investigation/Feasibility Study (RI/FS) at the Suffern
Village Well Field site, Village of Suffern, Rockland County, New York.
This RI/FS work recommended that the "No Action" remedial alternative be -,
implemented at this site. The RI/FS work also recommended that comprehensive: :
sampling and model verification programs be undertaken to confirm the conclusions
of the study. This Department endorses these technical recommendations.
The draft declaration for the Record of Decision (ROD) on the Suffern Well
Field RI/FS indicates that the model verification and sampling programs are operation
and maintenance (0 & M) activities, which are the responsibilities of th~ State
of New York. The draft declaration further states that the first year of these
o & M activities is considered start-up, which is eligible for Federal Superfund
monies. We do not agree that these programs should be responsibilities of New York
State. Instead, the U.S. Environmental Protecti~n Agency (USEPA) should be
responsible for the model verification program, until the mode1..is verified, and.
also be responsible for the ~ampling program. At the conclusion of these programs,
the data base will be evaluated to determine if further action is required. If
further action is not required (that is, the "No Action" alternative is implemented),
the State of New York will be responsible for future monitoring activities.
If you have any questions or comments regarding this matter, please contact
Mr. Robert Foltin or Mr. William Eberle,-of my staff, at (518) 457-1708.
Sincerely,
.1[~1-:t.-:.:,~,-/!-1..,- ':; "'.
rl\01
Norman H. Nosenchuck, P.E. \'
Director
Division of Solid and Hazardous Waste
cc:
G. Pavlou, USEPA Region II
W. McCabe, USEPA Region II
-------
. ~.
" ~
ATTACHMENT B
SUFFERN VILLAGE WELL FIELD
SUFFERN, ROCKLAND COUNTY, NEW YORK
RESPONSIVENESS SUMMARY
~
-------
~ 0" C)
-1-
Major commen;s raised during the public meeting held on August 19,
1987 at the Suffern Village Hall are summarized briefly below.
A complete transcript of this meeting is part of the administra-
tive record and is available therein. The ~Ublic comment period
extended from August loth until September 9 h, and written comments
are also addressed in this summary.
The NYSDEC chaired subject meeting, and presented a brief history
of the site, and the no-action alternative as the preferred solu-
tion. ERM personnel reviewed the objectives and conclusions of
the Remedial Investigation and Feasibility Study, the Risk Assess-
ment, and the alternative solutions that were considered.
1 - Question:
A question and answer period follows:
Answer:
2 - Question:
Answer:
_.
. . 3 - Question.1:
Relative to Alternative 1, explanation for scope
and cost was requested.
It was indicated that the costs were for a
sampling/analysis program and for model
confirmation work.
. .
.
~
Further, it was explained preliminarily that
for the first year EPA would bear 90% of the
cost, and DEC would assume the balance:
beyond this period the State would bear all
costs.
Who has responsibility for the overview/super-
vision of the monitoring program?
EPA advised that after the first "year start-
up period", that the State was responsible
for the continuance of the program. DEC
indicated that it would handle same, or per-
haps enter into an agreement with Suffern.
Implementation mechanism is still being
studied.
What happens if in the future other contami-
nants are found or other standards promul-
-------
Answer-::"
" . ,.
4 - Question:
Answer:
5 -
Comment:
- .
-2-
Either EPA or the State would reenter the
picture to investigate arid remediate as neces-
sary, either as a continuation of the current
scope of study and remediation, or as a second
phase (separate operab~~unit).
, ,
New standards would reqYire~revisions during
rthe design phase of ~~~t~5ici~. For those
..projects in which rem~:d!i"~l :'a;c.tion is, underway
or completed, a' reanalY$.fs' ~6£ the contaInination
,,:,wi~h. respect to its im~rac'{;qh: public' health and
the environment would' "1;e undertaken.and '.further
corrective measures, as ne.ce.ssary, would ,;be
. .~ 5 ,'. ',-.
' ..i,mpl emen,ted . <. ';.;; ':. ~!!"." ;",
"
.. . . '......
As a part of Question #3'/.~:9hc;:ern was expressed
that the financial burden would fall on the
communi ty for new regulations'~after a si te
"has been cleaned up". 1 ~riT
, ", ') ,;
EPAfs Federal Water Quality. ~rJteria as set
forth in the Clean Water Act ~re the same
figures (for the most part) fhat the State has
developed in its guidel ines, "a;,nd these are
consistant with currently deemed to be accept-
able risk levels; more stringentstji:ndards
merely reduce the risks further.
- - ,
The Rockland County Health D~partme~t~noted
that NYS Health Department i~~~onsidering
lowering the guideline maximum.organic
contaminant level from 50 ppb to 5 ppb,
justifying the concern of S.u~~E:!rn V,'j:1:;hr~e ~.
"'(1ml
The State Health Department 'en~red the
fOllowing statement into the i~pord:
~ .' ..
.~.." -
-~ '.£V
"The Rockland County Department of Health
in a number of environmental programs acts
as a local agent for the New Y~rk State
Department of Health and uses.~s a gUide,
the New York State Sanitary C9a~, and various
rules and regulations and envirgnmental
gUidelines.
" ,
.:..
, ,
-------
9' .....,4'
-3-
At this point the New York State Department
. ' ',' " .::" o-f Health has not adopted any standards for
.:; ,,'the maximum contaminant levels for 1,1,1, tri-
" ~ "ch1,oroethane. They have; - howeve r, recommended
,r 'in the past that rio amount of contaminant be
. 'preseht-in the drinking wate~ above 50 ppb.
, T,
, '
:!';:.r~\' ',:,.noif'~\-Recen~lY~ the State Commissioner of Health
:-39$2:1:; ':t/~; ,'fiai~ :;~40Qted a general pol icy 'that the publ ic
."':,,:>~';,!~J ,2L f,':)!" $'fi'od'~d:'~be subject only to the lowest amounts
'::L:'1t'~.J;K:~ ,e,-' j QasjUile of any contaminant possible in the
r';d:i,t~r.-!:'d_.!.CLlq w1fter,'~sj.1pply. ' r.,[,:
"O:''''i'c-; 'r";~~L: n$~!:j"'1-::::' ,""dJ ,,'.~ .." ."JC:
;.~j~;L;'~':', y-::s„h~1t>e'~ping wi th the St:ate:-'1fe"a.,1th Commissioner's
' general pol icy it is recommended tha t the
Village of Suffern take measures to reactivate
':c;;p as,",' :::~ ~tfie-ir aeration system so the lowest values
':-:0 11s~_=~ractical can be obtained in the Village water."
, 'J ,: ,':, 5 :f ~:, J 5 " " , ;
Th~ DEC & EPA emphasized that in the presence ot
a contaminant concentration exceeding standards,:
~,'~,; .sl:i ~j .'ar if the moni toring program did not confirm
-):1::'. ~rf:j 8:m,odel predictions and excessive contaminant
~c~:; er,j jlconcentrations could occur in drinking water,
:::';:' !:' 'ct° remediation program wO.uld be initiated.
. r:: ..:..1 ().J ~j S!j~":
, -
6 - Ques',tib1\fl:'B :'~ould no-action result in'concentrations
',presumably TCEA) less than 5 ppb?
Answet~~~~~!~~; in ,approximately 4 years, beyond 12/86,
~n~~9b!a~~th~-modelpredicts less than 5 ppb in the
~lo~~~:production wellso
doq c. ',:: .--.:. -..
7 - Stat>~me.rit!V r:':the ~Rcuft'apo River Commi ttee emphasized the
importance of maintaining the quality of the
,~,ij be::'.'a"'q,J'ifer which has the potential for supplying
:bJ9~eneeds of 50,000 ~eople from the Spring
, Valley and Suffern flelds.
! ,'169H :0 -:J,-",
~i~S 2ms:f~~~rther, the necessity. to secure the area,
9jr::.j2 /.'l'ncluding preventing dumping in the area,
,~biup ~ agpropriate fencing, etc, was emphasized.
::~j';p~ t/i1E ,jl:rso, the public should be made fully aware of
Ls,nsmnthe'necessity to protect this resource.
Rockland County Health Department noted their
activities with Rockland and Spring Valley to
-------
"
-4-
i~
.,.,..-
~
Ramapo River Committee noted the proposal of
a new landfill north of the present Town of .
Ramapo landfill where the geology is similar
to the Suffern Site, and therefore another
potential threat to the ,ubject aquifer.
The public was urged to be<;:ome. familiar with
th~ site to oppose the proP?~~daction.
'. . '.
' . ~ " ,
In a wri tten COrrimunication, the Mayor. of SUffern;.. v-!iiage has
. inquired as to t.he. capabil i ty of the model de~elo.ped~: ~or this
.~. project to predict the effect of leachqt~.. ttoirt,..:~1i~, ~amapo Land-
fill site (approximately, two miles north qJ Jf.hE!::':',*~J';ern well
. field) on the Suffern drinking water pb,pe'rti~'s,:~.:~';')'h~squestion
. is beyond the" scope ot, ~,th~ present .study-., an~':,~a~~:~~.en referred
::>to Leggette,~B'rashears ..&:'-Graham, Inc."'an(f-.thei.~',,t:espOrise will
'. -:1 be' communicated-..to the 'Mayor. . .'-:':_, . ....",
, .
.
, .
..
~'
------- |