United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R01 -87/023
July 1987
&EPA
Superfund
Record of Decision
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T€CHNICAL REPORT DATA
(Plt!tUt! nad InstNc/ion! on tht! nvt!nt! MIMt! com"lt!tintJ
1. R.'ORT NO. \2. 3. REC\'IENT'S ACCESSION NO.
EPA/ROD/ROl-87/023
4. TITLE AND SUITITLe 5. REPORT DATE
SUPERFUND RECORD OF DECISION Julv 24, 1987-
Re-Solve, MA e. PERFORMING ORGANIZATION CODE
Second Remedial Action - Final
7. AUTHORIS) 8. PERFORMING ORGANIZATION REPORT NO.
e. PER"ORMING ORGANIZATION NAME AND AODRESS 10. PROGRAM ELEMENT NO.
. 11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS 13. TYPE OF REPORT AND PERIOD COVERED
U.S. Environmental Protection Agency 14. SPONSORI"iG.fI.~IiN~goR~port
401 M Street, S.W.
washington, D.C. 20460 800/00
15. SUP'LEMENTARY NOTES
18. ABSTRACT
The Re-Solve, Inc. site is a former waste chemical reclamation facility situated on
six-acres o~nd .in North Dartmouth, Massachusetts. Bounded by wetlands to the north
and east, th~ land surrounding the site is predominantly zoned for single family
residential use. All residences obtain their water from private wells located on their
property. The Copicut River, located about 500 feet from the site, has been designated
for the protection and propagation of fish, other aquatic life, ~ildlife a~dprim~~~,a~d
's~condarycontact recreation. Between 195~nd 1980, Re-Svlve, Inc. handled a variety
of hazardous materials including solvents, waste oils, organic liquids and solids,
acids, alkalies, inorganic liquids and solids and PCBS. Residues from the distillation
tower, liquid sludge waste, impure solvents and burnt tires were disposed of in four
onsi te unlined lagoons. The lagoon contents were burned periodically to reduce the VOC
content. An oil waste that accumulated at the bottom of the degreaser distillation
still was disposed of on one portion of the site through landfarming. This oil waste
was also spread throughout the site to control dust. Cooling water from the
distillation tower was discharged to a shallow, onsite lagoon. In 1974 the
Massachusetts Division of Water Pollution Control issued Re-Solve, Inc. a license to
collect and dispose of hazardous waste. In December 1980 the Massachusetts Division of
Hazardous Waste agreed to accept Re-Solve's offer to surrender its disposal license on
(See Attached Sheet)
17. KEY WOROS ANO DOCUMENT ANALYSIS
.. DESCRI'TORS b.IOENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
Record of Decision
Re-Solve, MA
Second Remedial Action - Final
Contaminated Media: gw, soil, sediment
Key contaminants: VOCs, PCBs
11. DISTRIBUTION STATEMENT 1e. SECURITY CLASS (TI,i$ R,portl 21. NO. OF PAGES
None 208
20. SECURITY CLASS (TI,il pal" 22. PRICE
None
I'. ,.... 2220-1 (R... 4-77)
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INSTRUCTIONS
1,
REPORT NUMBER
Insert the lPA reporl number as it,appears on Ihe cover of Ihe publi.:;uion.
LEAVE BLANK
2.
3.
RECI,.ENTS ACCESSION NUMB.R
Reserved for use by e:a.:h reporl re':lpienl.
4. TITLE AND SUBTITLE
, Tille should Indicale .:Ie:arly iAnd briefly Ihe subje\:1 \:oyer:ap: uf Ihe reporl. ;and b.: ~i'I'I:ay\'~ I,rumin\,nlly. S.'I ,ul"ill." Ilu~,I. 11\ .m:ali\'r
Iype or olherwue subordinale 1110 main lille. When a report is rreparcd in moh,o Ih:an "ne yulul11\:, ,,'p':allhl: rnlll:ary 1111... :a,1\1 y,.l:lln.,
number and include sutllille for Ihe specific: lille,
REPORT DATE '
Each report shau carry a dale inc1icalinl al le~ul monlh and year, Indi..ale Ihe h:aSls UII \101...11 il "a' ...,Ie..le\l (qt.. J/J,c, 0' ;5$IIC', "tI'C' c'l
tlpproNl, diJ" of p'.ptlftllioll. flC,),
II.
I.
'ERFORMING ORGANIZATION COOl
Leave blank.
.,
7.
AUTHORISI
Give namels) in \:,)nvcnllonal ordcr (John R, 0«, 1. Rolx." Dot', c"('.), Lisl :aulhur's :aflil~lIulI if il ,I,,'f..rs lrum Ih.' I",rfu,mina: ,,'a:anc-
zalion.
I.
PERFORMING ORGANIZATION REPORT NUMBER
Insert if performlnl organlZallon WIshes 10 :aSSIIft Ihls number.
t.
PERFORMING ORGANIZATION NAME AND ADDRESS
Give name, sunt. cilY, state. and ZIP code, Lisl no more Ihan IWO levels of :an ur~nil:aliul1:a1 hire:"..hy,
10. PROGRAM ELEMENT NUMBER
, Use Ihe propam element number under whi.:h the report WilS prepared. Subor\lil1i1h: num""r\ 1II:a)' bI: ill.lu~.,.J IIII'iI,.'I\lh.....,..
11. CONTRACT/GRANT NUMBIR
Insut conuact OIittant number under which report won prepared.
..
12. SPONSORING AGENCY NAME AND ADDRESS
Include ZIP code.
13. TYPE OF REPORT AND PERIOD COVERED
"Indicall1nlenm liRa!. etc., and If applil:able. dallS covered.
1.. SPONSORING AGkNCY CODE
Insert appropriate code.
115. SUPPUMENTARY NOTIS
Enllr informalion nOI included elsewhere but useful. such iAS:
To be published in. Supersedes. Supplemenls. ,nc.
11. ABSTRACT .
Include a brief {200 word! 0' (.U) faclual summary of Ihe mOSI -ilJnlliunl Infurmilllun ,'unlilln\',11II "", [.:'I'0rl. II 111,' "'1''''1 ,....lalli' ..
sipificant bibliopaphy or lileralure survey, menlion il here.
Prepared il1 \:uoperilliun wllh, rran\bl""1 ..I. l'r"""'III\'.J :al """"',,'''''' Itl,
17. KEY WORDS AND DOCUMENT ANALYSIS
(a) DESCRIPTORS. Selecl from Ihe The!\lurus of I::nlinecrir... ;and S.:lelllllk Tl:rll1~ Ihe prupc:r ilUIII"'II':~ 1\'1111\ IhOllllll:nlll'y Ih.. nlajm
concept of the research and are sufficiently SP.CltiC and precl5\: 10 be u5\:d iI~ 111\11::\ I:nlrlCs lur ..~lill"~ln~.
(b) IDENTIFIERS AND OPEN.ENDED TERMS. Use identifien for pro;"1 nilnM. ~udc nam.:'. "4u1pml:nl ~\',,~n:aIUr\. ..I\:. u~ "I"''''
ended terms written In dcsc:riptor form for those subjects for which no dC!K:rlptur c-,ists.
(c) COSA TI HlLD GROUP. Ficld and Stoup assil"menu ,ue 10 be Iilkl:n I'rom Ihe 196$ ('05"'11 Suhj.'\:1 (':aI"I!"IY Usi. Sin.:\: Ihe nlil'
jorilY of Qocumenls are multidiscIplinary in nalure, Ihe Primary Held/Group as."l&nmenU\' will be """.....' ~i""II'hil.:, ar\:a..1 hUlu:an
endeavor. or type of physial object. The applicalionls) will be crussofefercnccd wllh ..:.'undilry I ..'1,1/1 iWUI' ""II!" III\' II " 111011 ""III 1'1,1111'"
Ihe primary poSUnltsl.
,I. DISTRIBUTION STATEMENT
Denole releasabilily 10 Ihe publi.: or linlltallon for reasons uther Ihan \<:\:Uflly fur cJ\:ample "RI:I\':a'\' 1:111111'11.'\1." ( II\' :a"1! "~"II..I"lIly III
Ihe public. wnh address ilnQ pn.:c.
'9.8120. SECURITY CLASSIFICATION
DO NOT submil c~ssllicd rcporrs to Ihc NiAlional Tc.:hnicilllnformilliun ~rvicc.
21. NUMBER OF PAGES
Insert Ihe 10lal number of pages. includinllhis onc and unnumbered pall='. bul c,,\:ludl: d.'lnbullun h'l. 'I any.
22. PRICI
Insert the price ~I by the Nalional rechnicallnformation S.:rvicc ur the Governmenl I'nnling om.:c. .1' knuwn,
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Record of Decision
Remedial Alternative Selection
Site Name and Location
Re-Solve, Inc. Site
North Dartmouth, Massachusetts
Statement ~ Purpose
This Decision Document represents the selected remedial action
for this site developed in accordance with the Comprehensive
Environmental Response, Compensation, and Liability Act of 1980
(CERCLA) ,. as amended by the Superfund Amendments and Reauthorization
Act of 1986 (SARA), and to the extent practicable, the National
Contingency Plan (NCP); 40 CFR Part 300 et seq., 47 Federal
Register 31180 (July 16, 1982), as amendea.
The Commonwealth of Massachusetts has concurred on the selected
remedy and determined, through a detailed evaluation, that the
selected remedy is consistent'~ith M.G.L. ch. 21E.
Statement of Basis
This decision is based on the administrative record which was
developed in accordance with section 113(k) of CERCLA and which
'~s available for public review at the information repositories
(index attached). The attached index identifies the items which
comprise the administrative record upon which the selection of a
remedial action is based.
Description of the Selected Remedy
The selected remedy for the Re-SOlve, Inc. site is a comprehensive
approach for site remediation which includes both a source control
and management of migration Component.
The source control component entails:
o
Excavation of 22~500 cubic yards of PCB contaminated soils located
in the unsaturated zone and treatment on-site in a mobile dechlorin-
ation facility. The health-based cleanup level for on-site soils
contaminated with PCBs is 25 ppm. This cleanup level corresponds
to a 10-5 cancer risk level. SOils will be treated in the dechlorin
ation facility to a level of 25 ppm PCBs and then placed back on-sit.
Excavation of 3000 cubic yards of PCB contaminated sediments
located in wetland resource areas to the north and east of the
site and treatment on-site in the mobile dechlorination facility.
The cleanup level for PCB contaminated sediments is I ppm.
Achievement of the target cleanup level will require the disturb-
ance and temporary loss of areas classified as wetlands. The
unavoidable impacts to these resource areas will be mitigated to
the maximum extent possible and following such activities, a
wetland restoration program will be implemented. .
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o
Dechlorination is an innovative technology which has been proven
to be ,ffective -in the treatment of PCB contaminated soils on
the bench-scale and pilot-scale level. However, it will be
necessary to conduct pilot-scale studies to determine the imple-
mentability of this technology on a full-scale level. If-
dechl~rination, based on t~e results of the pilot-scale studies
is determined not to be implementable at the Re-Solve site, EPA
will select on-site incineration as the principal treatment
technology for this component of the selected remedy.
o - It is estimated that it will take two (2) years to treat 25,500
cubic y.rds of PCB contaminated soils and sediments. This estimate
is for construction/operation time only, and does not include the
time for design, bidding and awarding of the construction contract.
The management of migration component will be implemented upon
completion of the source control component. This component entails:
o
Active restoration of the overburden and bedrock aquifers con-
taminated with volatile organic compounds (VOCs) using on-site
treatment involving air stripping and carbon adsorption.
Groundwater will be treated to reduce contaminants to levels
which result in an excess ca~cer risk of 1 X 10-5, assuming -
additivity. EPA estimates tnat this target remediation level
can be achieved within 10 years. .
EiA has determined that it is technically infeasible to remediate
PCBs located in the saturated zone soil matrix on-site and ensure
that the resultant concentration in groundwater would attain a
level that is equivalent to a 10-5 cancer risk level. However,
treatment of VOCs will render the PCBs relatively immObile, thus
restricting contamination to the waste management area, only.
Since PCBs will be present in groundwater in excess of the health-
based cleanup level upon completion of groundwater remediation, it
will be necessary to implement institutional controls on ground-
water use within the waste management boundary.
o
The estimated present worth cost for the Source control component is
$9,237,000 ana the groundwater remediation component is $10,674,000.
The total estimated cost for the selected remedy for tbe Re-Solve,
Inc. site is $19,911,000.
Declaration
The selected remedy is protective of human ~ealth and the environment,
attains Federal and State requirements that are applicable or relevant
and appropriate, and is cost-effective. This remedy satisfies the
statutory preference for treatment that permanently and significantly
reduces' the volume, toxicity and mobility of the hazardous substances
pollutants and contaminants, as a principal element. Finally, it is
determined that this remedy utilizes permanent solutions and alter-
native treatment technologies to the maximum extent practicable.
J!e2Wr7
Da e
L - ,...~
~LI,?.;).L
M1C e R. Delan -
Regional Administrator,
-~
-
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ROD Decision Summary
Re-Solve, Inc. Superfund Site
North Dartmouth, Massachusetts
,
~,.
~
Septembe~ 24, 1987
u.S. Environmental Protection Agency
Region I
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TABLE OF CONTENTS
Sectlon
Page
I.
Slte Name, Locatlon and
Descrlptlon....................l
II.
Slte
H 1 S to ry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
III.
Enforcement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
IV.
Communlty Relatlons HlstorY............................17
V.
Alternatlves Evaluatlon
A.
I~troductlon...........................................19
B.
Response Objectlves....................................20
C.
Technology Development and Screenlng...................22
D.
Development of Alternatlves and Inltlal
Screenlng of Alternatlves...........................22
E. --
. Detalled AnalYSls of Alternatlves......................22
VI.
Selectlon of Remedy
Descrlptlon of the Selected
RemedY.....................48
A.
1.
Scope and Functlon of the Selected RemedY..............48
2.
Performance Goals......................................S3
B.
Statutory Determlnatlons...............................63
1.
Protectlveness.........................................64
2.
Conslstency wlth Other Envlronmental Laws..............68
3.
Cost Effectlveness and Utll1zatlon of
Permanent Solutlons and Alternatlve
Treatment Technologles or Resource Recovery
Technologles to the MaXlmum Extent Practlcable.........71
Evaluatl0n of Selected Remedy vs Other
Alternatlves ..........................................74
C.
VII. .
State
Ro 1 e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3
A.
Appendlces
Appllcable or Relevant and Approprlate Requlrements
for the Commonwealth of Massachusetts
B.
State Evaluatlon and Concurrence Memorandum
Data Base - Flgures and Tables
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ROD Decision Summary
Re-Solve, Inc.
North Dartmouth, Massachusetts
'"1.
Site Name, Location ~ Description
The Re-Solve, Inc. site (Nthe siteN) is a former waste chemical
reclamation facility situated o~ a six acre parcel of land in the
Southeastern Massachusetts town of North Dartmouth. As shown in
Figure C-l, the site is located approximately two miles north of
Interstate Highway 195 and Reed Road Interchange on the east side
of North Hixville Road. The site 1s bounded by wetlands to the
north and east and a pine and mixed hardwood forested area to the
south and west. An Algonquin Gas Pipeline right-of-way abuts
the eastern boundary of the site.
The land surrounding the Re-Solve site is predominately zoned for
single family residential use, with required lot sizes of 40,000
square feet or larger. Two auto salvage yards are located on
North Hixville Road, 500 feet and 300 feet respectively to the
north-northwest of the site. A former gravel pit located to the
northwest has been closed and ,~evegetated. To the northeast of
the site approximately 180 acres are owned by the Rod and Gun
Club of New Bedford. This land is used by the club for hunting
(raBbits"and pheasants are stocked by the club), fishing, and
target shooting. Part of the acreage is also used in conjunction
with a forestry management program. Twenty-five acres of land
immediately south of the site bordering the Algonquin Gas
Pipeline right-of-way and the Copicut River are held by the
Dartmouth Natural Resource Tru$t.
A town forest is located about two miles south of the site,
adjacent to Interstate Highway 195. No rare or endangered species,
plants or animals have been reported within a two mile radius of
the site.
According to the 1980 Massachusetts Census, North Dartmouth has
an area of about 62 square miles and a population of approximately
26,000. The 1980 population represents an increase of approximately
17 percent over the 1975 population of 21,600 persons. Based on
the 1980 census, approximately 114 people live within a one half
mile radius of the site, and approximately 326 people l1ve within
a one mile radius of the site. Two residences are located within
150 yards of the site, one to the northwest and the other to the
southwest, and six other residences are found along North Hixville
Road within one quarter mile of the site.
All residences in the area obtain their water from private wells
located on their property.
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The Copicut River, ciassified as Class B by the Commonwealth of
Massachusetts, is located about 500 feet directly east of the
site. Class B waters are designated for protection and propagation
of fish, other aquatic life, and wildlife and for primary and
secondary contact recreation.
The Copicut River drains directly into Cornell Pond, approximately
one quarter of a mile down river from the site. Cornell Pond is
popular for sport fishing with horn pout, perch, and pickerel
the common species. Ou.tflow from Cornell Pond merges with Shingle
Island River which then flows into Noquochoke Lake, located
about two miles downstream of Cornell Pond (see Figure C-l).
Noquochoke Lake is highly enriched with nutrients and stratifies
in the summer months, so that sufficient levels of dissolved
oxygen may not be present to support a healthy aquatic community.
A summary of local climatological data shows that annual precipi-
tation averages 41 inches in Dartmouth, with most annual totals
within 14 percent of the normal. Average monthly precipitation
ranges from 2.2 inches to 4.1 inches. Temperatures range from an
average low of 32 degrees Fahrenheit on January 1 to about 72
degrees Fahrenheit on July 1. .
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II.
~ Histor'i
Re-Solve, Inc. operated as a waste chemical reclamation facility
for 24 years until ixs closure in 1980. A variety of hazardous
materials were handled at the Re-Solve site including solvents,
waste oils, organic liquids and solids, acids, alkalies, inorganic
liquids and solids and PCBs. Historically, the operators disposed
of the hazardous byproducts from the distillation process in two
ways. The residues from the distillation tower, .liquid sludge
waste and impure solvents were disposed of in four unlined lagoons
on-site. The lagoon contents were burned periodically to reduce
the volatile organic content. An oil waste that accumulated at
the bottom of the degreaser distillation still was disposed of
on one portion of the site through a method known as landfarming.
This oil waste was also spread throughout the site to control
dust. Cooling water from the distillation tower was discharged
to a shallow on-site lagoon in the eastern portion of the site.
It is alleged that residues from burned tires were also disposed
of in the lagoons.
In 1974, the Massachusetts Division of Water Pollution Control
issued Re-Solve, Inc. a license to collect and dispose of hazardous
waste. On October 21, 1980, Re-Solve offered to surrender its
disposal license. On December 23, 1980, the Massachusetts Division
of Hazardous Waste agreed to accept Re-Solve's offer, on the
con~ition that all hazardous waste be removed from the site.
Inspection and monitoring of the site by the State at the time
showed that no migration of contaminants was occurring from the
four lagoons and that vehicle inspection and manifest requirements
were adhered t.o for off-si te disposal of drum and tank wastes.
In the following months, there was little evidence of responsive
activity on the part of Re-Solve, Inc. and in March of 1981,
the Massachusetts Attorney General's Office became involved.
Later in 1981, all drums and other debris, including buildings
on the site, were removed from the site by Re-Solve, Inc. Follow-
ing this, the site, with the exception of the slab foundations
and loading and unloading pads, was covered with an unknown
amount of sand. These activities occurred under the direction
of the present site owner. The contents of the four on-site
lagoons were not removed.
On June 19, 1981, the Massachusetts Department of Environmental
Ouality Engineering (MA DEOE) submitted a request to EPA that the
Re-Solve, Inc. site be placed on the Superfund National Priorities
List (NPL). In October of 1981, EPA released an interim NPL list
of 115 priority hazardous waste sites. The Re-Solve site was
on the list, thus becoming eligible for federal assistance as
part of the Superfund program. On December 30, 1982, the Re-Solve
site was placed on EPA's proposed NPL. At the time, it was
ranked as number 156 of a total of 418 hazardous waste sites. In
September of 1983, the Re-Solve Inc site was placed on the Final
NPL. On July 16, 1982, EPA published a Remedial Action Master
Plan (RAMP) for the site. The primary purpose of the RAMP was
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sequence, and schedule of remedial projects which would be
appropriate at the site.
A Remedial I~vestigation and Feasibility Study (RI/FS), initiated
in the fall of 1982 and completed in June of 19~3, was conducted
to assess the extent of on-site source contamination and evaluate
remedial alternatives. The sampling program conducted as part of .
the RI provided chemical analyses for air, surface water, ground-
water, soil, lagoon wastes and sediment samples.
Indications of contaminated areas and waste types identified in
previous studies were also verified in the 1983 RI/FS. The study
identified the following four" areas, as shown in Figure C-2,
as contaminant sources:
( 2)
( 3)
(1 )
Four unlined lagoons in northern part of site.
PCB content was found to vary significantly with depth in
the lagoons but was generally greater than 500 ppm. Other
contaminants found in the lagoon waste, at concentrations"
in excess of 5000 ppm, include isophorone, ethylbenzene,
toluene, o-xylene, and various phthalates.
Filled cooling water pond at the eastern boundary of the
site.
~
Prior to being filled in 1981, HA DEQE (October, 1980) sample~
the active cooling pond water and found high concentrations
of methylene chloride (1.45 ppm), acetone (1.5 ppm), tri-
chloroethY'ene (860 ppb), methylethyl ketone (780 ppb),
" and other organics at less than 100 ppb.
Areas of oil spreading in the western and southwestern
portions of the site.
Waste oil was deposited for many years in the areas along
the western boundary of the site just south of the access
road entrance. The upper zone was modified by plowing or
discing of wastes into the soil. Surface soil samples
were found to contain PCB concentrations ranging from
15,000 to 52,000 ppm. "Soil boring samples also collected
in this area indicated subsurface concentrations of PCB
from 4 to over 200,000 ppm. Other organics, including
phenols, trich10robenzene, and bis(2-ethylhexyl)phthalate,
were also detected at high concentrations.
(4) " Foundations and concrete pads associated with structures
which had existed on-site at one time (-structural remnantsM)
and contaminated soils (Mhot spots.).
The 1983 study identified the on-site contamination source as
approximately 3,100 cubic yards of lagoon wastes and 3,900 cubic
yards of contaminated soil. Based on a review of analytical data
from 35 monitoring wells, it was postulated that the extent of
.'
.'
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.
-5-
groundwater contamination was bounded by the Copicut River and
Carol's Brook.
In June of 1983, EPA proposed a source control remedial action
that included excavation of 7000 cubic yards of contaminated
lagoon waste and soil with PCB concentrations greater than 50
ppm, treatment (waste stabilization/fixation process) on-site and
encapsulation. Based on an evaluation of comments received
during the public comment period, EPA modified its recommended
'remedial action. The selected remedial action was for the exca-
vation o~ 7000 cubic yards of source material (i.e. four waste
lagoon areas, oil spreading area and other -hot spots"), treatment
and transportation to an off-site disposal f5cility, and encap-
sulation of the site. A Record of Decision describing this
remedial action was approved on July 1, 1983.
Through an. interagency agreement, EPA contracted with the Corps
of Engi~eers (US COE) to perform the design and construction of
the selected remedy. During remedial design, the quantity of
waste requiring disposal was increased to a total of 15,000 cubic
yards. The US COE completed the design and in November, 1983
initiated the bidding procedures for the selection of a sub-
contractor to carry out the remedy. The awarding of the subcontract.
to CECOS Environmental Inc. was delayed five months due to a bid
protest by a third party, but construction on-site did begin in
Jul~ of 1984. Delays leading to shutdown of the project occurred
when EPA Region I was inform~d that, due to regulatory requirements,
only specific wastes from the Re-Solve facility were acceptable
for disposal at CECOS facilities in Region II and Region v.
Ultimately, soil from the four lagoons plus the soil mixed with
it was sent to a CECOS facility in Ohio. All other soils went
to a CECOS facility in Niagara Falls, New York.
Near the completion of the excavation of 15,000 cubic yards of
soils, additional site investigation studies were conducted to
evaluate the effectiveness of the remedial action. This work
consisted of 48 on-site shallow soil borings and a series of 5
test pits. These studies indicated that extensive PCB contami-
nation at concentrations greater than 50 ppm still existed in
on-site so~ls to a depth of 10 feet below seasonal low ground-
water. The US COE so informed EPA in April of 1985. At that
point, the remedial action CQntract was terminated and a Supple-
mental RI was initiated to determine the further extent of on-site
residual contamination in soils. Encapsulation of the site did
not occur.
Concurrent with the US COE activity on-site, EPA had initiated an
Off-s.ite RI/FS in September of 1983 to assess the extent of con-
tamination that had migrated beyond the boundaries of the site.
The final draft of that RI was completed in February of 1985.
Results from the off-site investigation as well as the on-site
RI/FS (1983) and other pertinent data and information developed
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.
-6-
limits of 'off-site contamination and to evaluate potential remedial
measures.
The four ~ajor sources of contamination (Figure C-2) identified
in the on-site RI/FS (1983) were confirmed by the analyses obtained
from the installation of 45 groundwater monitoring wells at 25
locations, surface water and sediment sampling, soil borings, test
pit. excavations and lagoon depth probing and analyses. Based on
samples taken from these media during the on-site RI(1983) and
again in 1984 during the off-site RI (1985) the fOllowing were
concluded:
o
Contaminants are leaching from the intermediate depths of
the lagoons where there has been no effective sealing of the
side slopes. This leaching process provides a source of
both on-site and off-site contamination of the groundwater
and soils. In addition, during periods of high precip-
itation the lagoons would overflow, thus contaminating
the sediments in the wetlands north of the site and the
unnamed tributary.
o
The unlined cooling water pond is acting as a continuous
source of groundwater contamination. Precipitation and/or
run-off entering this area causes contaminants to seep
into the groundwater and then flow laterally in a south-
easterly direction from the site towards the Copicut River
and Cornell Pond.
-=ill
o
At test pits ins~alled in the oil spreading area a10ng the
western boundary of the site in this area, the water
table was observed to intersect the zone of high PCB
concentrations. Oils were noted floating on the water
which had accumulated in one test pit as well as in soils
in the upper eight inches.
The results of the off-site RI (1985) indicated that the site is
acting as a continuous source of contamination and that off-site
contamination emanating from the Re-Solve site impacts upon
groundwater, surface water and sediment.
The results of an extensive groundwater sampling program conducted
in May, 1983 and January, 1984 are presented in Figures C-3 and C-4.
These data clearly indicate a southeastward movement of the
contaminant plume in both the overburden and bedrock aquifers.
The area of groundwater contamination in the overburden aquifer
is approximately bounded on the south and east by Carol's Brook
and the Copicut River, but contamination in the bedrock does
extend beyond these two surface water bodies. The bedrock
contamination east of the Copicut River appears due to localized
effects, while the bedrock contamination south of Carol's Brook
indicates that this brook is acting as only a partial hydrologic
barrier.
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The Copicut River, Carol's Brook, the unnamed tributary and Cornell
Pond are the primary surtace water~ in the vicinity of the Re-Solve
site. The highest levels of surface water contamination were'
detected in the unnamed tributary and the Copicut River. Progress-
ively decreasing cory cent rations of volatile organics were detected
downstrea~ from the site in Cornell Pond and the Copicut River.
The principal off-site locations containing elevated levels of
PCBs in sediments are shown in Figure C-5. . These areas pr.edominate
.in the wetland area north of the si te, and the unnamed tributary
to the west. PCBs were not detected in the sediments of Cornell
Pond but a concentration of 1.7 ppm was observed in the sediment
of the Copicut River downstream of its confluence with Carol's
Brook. It appears that sediment transport mechanisms are slowly
dispersing fine grained sediments, along with adsorbed PCBs,
downstream.
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In April 1985, the off-site FS for the site was nearing ~ompletion
when EPA was informed by the US COE of the extent of contamination
that still existed on-site. As part of the development of
alternatives in the off-site FS, it had been assumed that the
source removal activity on-site would be completed and that the
on-site cap would be already ~p place. Due to the discovery of
additional contamination, the cap was not installed and EPA
elected to conduct a Supplemental RI to determine the nature and
extAnt of contamination in on-site soils and to supplement infor-
mation presented in the off-site RI. It was determined that,
upon completion of a Supplemental RI, a comprehensive FS would
be developed for both source control and management of migration.
Current Status
"
The Supplemental RI was initiated in September of 1985 and com- .
pleted in February of 1987. An extensive soil boring investigation
was conducted to determine the nature and extent of contamination
in soils. This program consisted of a total of 56 borings, 44
of which were on-site, and 12 of which were off-site. Fifty percent
of the on-site boreholes extended to bedrock. Each boring included
continuous split-spoon sampling with samples being collected at
approximately two foot intervals. These samples were then analyzed
for PCB and volatile organics and other Hazardous Substance List
(HSL) compounds.
Total Volatile Organics
"
Samples collected during the soil boring program were analyzed for
total volatile organics (TVO). The analyses show that, depending
on the depth and location of the sample, contamination ranges
from lows of 1-100 ppb to highs of 10-1,000 ppm. Figures C-6
and C-7 illustrate these data by delineating areas of significant
contamination at various depths. For presentation purposes, levels
greater than 50 ppm and greater than 10 ppm of TVO in soil were
selected to represent areas of contamination. These areas are not
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intended to represent the limits of contamination, but rather
the location of possible source areas. There is a tot~l of
approximately 31,000 cubic yards (c.y.) soils contaminated with
TVO greater than 10 ppm, 20,000 of that being saturated (below
grQundwater)' and 11,000 being unsaturated (above groundwater).
PCB
-
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pata representing the extent of PCB contamination greater than
50 ppm and greater than 10 ppm are presented in Figures C-8 and C-9.
These data represent a similar pattern to that shown on Figures C-6
and C-7 for the total volatile organic compounds, indicating several
distinct source areas. These figures show that, in relative terms,
the PCB contamination is located in the same source areas as the
TVO contamination and is generally more widespread than TVO
contamination. Approximately 61,000 c.y. of soil is contaminated
with PCBs greater than 10 ppm, 37,000 c.y. being- saturated and
24,000 being unsaturated.
.Q!l! Summary
Analysis of the soil boring program on the Re-Solve Site indicated
the existence of four distinctive source areas or Mhot spotsM
Thes£ are~s were similar for both the total volatile organics and
PCBs, as illustrated in Figures C-6 through C-9, and are identified
as follows:
o
Former Lagoon Area
Oil Spreading Area
o
Cooling Pond Area
Smaller Localized Areas (Mhot spotsM)
o
o
A primary area of concern is located in the northwest quadrant
surrounding observation well SB-25. A review of the past site
history at this location reveals that this area was the site of
the waste oil spreading operation. The soil boring results in
this area indicate high levels of total volatile organic contam-
ination (2,666 ppm in SB-25N). In addition, PCB levels in the
500 ppm range, penetrating through the overburden down twenty
feet to bedrock, were found in SB-25N.
/~
It is unusual for PCB compounds to be highly mobile due to low
solubility of the PCB constituent in water. However, the migration
of PCB compounds in groundwater at the Re-Solve site is dramatically
increased due to the presence of various organic solvents such
as hexane, carbon tetrachloride, benzene, methylene chloride and
acetone. PCB compounds form complexes with, and dissolve in, such
compounds, thus increasing the mobility of PCBs in groundwaterl. .
Carbon tetrachloride and methylene chloride have greater specific
gravities than water, so PCBs dissolved in these compounds could
migrate downward in the aquifer. In addition, long term surface
loading of waste oils at a high rate caused extensive mounding
of these contaminants and subsequent downward migration to lower
sections of the overburden aquifer.
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The second locality of high soil contamination is the former
site of the waste lagoons situated in the northern section of
the site. An analysis of the soil borings at the 5B-305 location
shows high levels of the following organic compounds: '
o
o
,
,
Methylene chloride
2-Butanone (MEK)
Trans-l,2-Dichloroethylene
Trichloroethylene
The concentration and depths of penetration of these contaminants
demonstrate that this area is also a substantial source of
groundwater contamination. .
o
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4-Methyl-2-Pentanone
Tetrachloroethylene
Toluene
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The third area of concern is the location of the former cooling
pond. The numerous soil borings at this locale show significant
concentrations of various organics, particularly acetone and
2-butanone (MEK).
Other areas of soil contamination, so-called -hot spots,- are
situated in the vicinity of the former septic system and the low
drainage areas on the pipeline right-of-way. The soil boring
data exhibit low levels of PCBs and high levels of acetone,
methylene chloride, 2-butanone (MEK), trichloroethylene,
4-methyl-2-pentanone and tetrachloroethane.
~
Groundwater
.
Extensive excavation at locations across the site during the 1983
remedial action removed substantial portions of the contaminated
soil matrix. However, a significant quantity of source material
still remains, resulting in widespread contamination of on-site
groundwater from volatile organics. and extractable organics.
Groundwater flow is from the site area (east of North Hixville
Road) to the east and southeast towards the Copicut River and
the unnamed tributary. The contaminants are found downgradient
in both the overburden and bedrock aquifers as well as the surface
wa ters.
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The overburden at the site consists of rather permeable sands
and gravels ranging in thickness from less than 10 ft to about
28 ft at one location. Generally, but with some exceptions, a
till layer is found in contact with the bedrock and below the
surficial sands and gravels. The thickness of the till layer
over the study area is variable, ranging from 0 to over 2S ft.
Numerous large boulders, up to 5 ft in diameter, are present in
the overburden at the site. These are primarily found in the
till layer, but they are also present in the overlying permeable
sands and gravels. Monitoring wells installed in the upper
sands and gravels were capable of being pumped at some locations
at rates of up to 10 to 14 gallons per minute (gpm). 5lug test
data shows transmissivities ranging from 100 to 176 ft2/day.
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Groundwater contours for November, 1985 and July, 1986 respectively
are presented in Figures C-IO and C-ll. These contours indicate
that approximately 90-95. per~ent of the groundwater from the
site which discharges to the surface water system enters either
the unnamed tributary that bounds the site to the northeast or
the Copicut River. Surface water flow data collected as part of
the Supplemental RI shows that during high water table conditions,
most of the groundwater is intercepted by the unnamed tributary.
A small portion of the groundwater outflow to the surface water
may discharge to Carol's Brook, but this is minimal. With a
lower groundwater table, groundwater does not discharge to the
unnamed tributary, but enters the Copicut River directly.
Historical groundwater contaminant plume data are presented in
Table C-l. The groundwater contaminant plume in the overburden
and bedrock aquifers are shown in Figures C-12 and C-13,
respectively.
Groundwater sampling at 16 observation well locations, primarily
at on-site and immediate off-site locations, indicated PCB con-
tamination ranging from 4 ppb to 1200 ppb in unfiltered groundwater
during the November and December 1985 sampling events. However,
PCBs are relatively insoluble In water with a range of 2.5,ppb -
15 ppb sOlubility. The existence of high levels of PCBs in
groundwater samples at the locations tested is, to a great extent,
beli.ved attributable to PCBs adhering to silt and suspended solids
sampled with the unfiltered groundwater samples. To verify this,
a second sampling was conducted in July of 1986. Groundwater
samples were filtered through a 0.45 micron standard filter for
organic analyses to determine if the PCB contaminants detected
were, in fact, adsorbed onto silt and soil particles.
The July 1986 sampling of filtored groundwater at ten of the
observation well locations showed PCBs at three of the observation
wells as indicated below. 'The renaining seven wells did not
indicate the presence of PCBs in groundwater.
Observation Well
Total PCB Concentration (ppb) ,
SW
0\' -SB-255
OW-SB-34S
Nov/Dec.1985
(unfiltered)
5.5
1160
6
July 1986
(filtered)
1.4
52
9.7
This information indicated that PCB oils at OW-SB-25S are present
in groundwater at levels higher than the 15 ppb maximum solubility.
The presence of other volatile organic compounds in which PCBs
are soluble increases the presence of PCBs in the groundwater.
Soil borings and groundwater samples at the SB-25S location
ind'icate high concentrat ions of volati Ie organics and PCB contam-
inants at depths throughout the thickness of the overburden
aquifer. The overburden contaminant migration plume is almost
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entirely discharging into the unnamed tributary and the Copicut
River as indicated by the lack of, or low levels of, contamin-
ation in overburden observa~ion wells east of the, Copicut River.
In addition, the pattern of surface water contamination found in
the Copicut River and unnamed tributary supports the conclusion
that the overburden aquifer is largely discharging into the
unnamed tributary and Copicut River. The unnamed tributary
appears to be a receptor of contaminant groundwater outflows and
exhibits, consistent contaminant concentrations in the 2-3 ppm
,total volatile organic 'range at its downstream portion. The
Copicut River is also a primary receptor of contaminant outflow,
exhibiting consistent contaminant levels of approximately 100 ppb
downstream of the site before the confluence with the unnamed
tributary. '
Contaminants in the bedrock aquifer have migrated under surface
water to the eastern side of the Copicut River'and south of,
Carol's Brook, as illustrated in Figure C-13. As evidenced by
drilling operations at some locations across the study area from
th~ 1985 Off-site RI and boring logs from the Supplemental RI,
bedrock at some locations is extensively fractured. Groundwater
in the fractured bedrock aquifer flows in a similar direction to
that of the overburden aquifer. Contaminants in the bedrock
groundwater discharge to the Copicut River. Contaminant migration
east of the Copicut may occur during the transient conditions of
higA water table conditions which causes short-term downward
vertical gradients. However, the Copicut River soon recovers and
discharge to the Copicut continues. These short-term reversals
of flow do not seem to be significant enough for contamination to
flow past the Copicut River. Further, a more recently installed
off-site cluster of monitoring wells does not exhibit any contamin-
ation in either the overburden or bedrock aquifers, indicating
that the contaminant plume has not migrated to that downgradient
area.
As indicated in these groundwater analyses, contaminant flow in
the overburden aquifer is primarily towards the Copicut River.
Some of the contaminants have higher specific gravities than
water. This fact, in combination with precipitation recharge,
contaminant recharge rates, and possible seasonal downward gra-
dients in the contaminated sandy soils, can cause a downward
migration of contaminants in the overburden aquifer.
Sediments
The highest concentrations of PCBs in sediments were found in
the wetland north of the lagoon area and in the unnamed tri-
butary. Lower levels were found in Carol's Brook, the Copicut
River, Cornell Pond and downstream to above the confluence of the
Copicut River and the Shingle Island River. Phthalates were found
in the wetland area as well. Other volatile organic contaminants
were found in sediments from all of the above areas, as well as
the Shingle Island River.
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-12-
.',
Fish sampling was conducted at two stations downstream of the Re-
Solve site to determine if PCBs were bioaccumulating in aquatic
life. one composite sample, consisting of redfin pickerel and
American eel, taken from the Copicut River sampling station, was
found to contain 20 ppm PCBs. Because eels generally have higher
levels of PCBs than other species in the sa~e water, it is likely
that the greater portion of the 20 ppm PCBs was contributed by
the eel rather than the redfin pickerel. The other seven fish
samples had less than 2 ppm PCBs. ,
The action level established by the Federal Food and Drug Admini-
stration indicating that fish is safe for consumption is 2 ppm
PCBs. In August, 1986, EPA, MA DEOE and the Massachusetts
Department of Public Health (MA DPH) issued ari advisory alerting
the public that eels caught in the Copicut River should not be
consumed. EPA, MA DEOE and MA DPH posted warning signs, in both
English and Portuguese, along,the Copicut River and the site
vicinity, warning against consumption of eels.
",
Residential Wells
EPA sampled fifty-six residential wells located both upgradient
and downgradient of the site, ..to determine if site con~amination
was impacting the quality of drinking water in the area. Of the
fifty-six wells, fourteen wells were found to be contaminated with
low~evels of organic compounds and four were found to contain lead
in excess of EPA's Primary Drinking Water Standard. Residential
wells that contained organic compounds that are categorized as
potential carcinogens were re-sampled by EPA. None of the original
conta~inants found in the first sampling round were detected in
two subsequent sampling rounds. The current quality of drinking
water in residential wells located in the vicinity of the site
is not considered to have been noticeably affected by contaminants
originating from the site.
Although lead was detected in on-site soils, EPA does not attribute
the lead detected in these wells to the site. The primary reason
for this determination is that these wells are located both
upgradient and downgradient to the site and therefore, there is
no hydrogeologic connection between the site and all of the wells.
Elevated lead levels are commonly due to naturally occurring,
lead in 80il, corrosion of lead piping and connections, residues
from lead paint or a combination of these and other sources.
Risk Assessment
-
The Baseline Risk Assessment was conducted to assess the potential
risks to human health and freshwater aquatic life associated with
exposure to contaminants from the Re-Solve site in the absence of
re~ediation. A subset of eight of the more than 50 chemicals
detected at the Re-Solve site in soils, sediments, groundwater
and surface water were selected for detailed evaluation of
potential human health risks. PCB-contaminated sediments were
considered to pose the greatest environmental risks at the.
Re-Solve site. Consequently, PCBs were selected for detailed
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evaluation with respect to their effects on freshwater aquat~c
life. Several exposure pathways under both present and future
site use conditions were evaluated, and the potential risks
associated with these pathways were estimated.
Under present site use conditions, five pathways for human exposure
and one pathway for aquatic life exposure were evaluated. The
relevant pathways for human exposure were: direct contact with
on- and off-site soils and subsequent absorption of contaminants
through the skin, or as a result of incidental soil ingestion:
inhalation of volatile organic compounds released from on-site
soils and surface water: inhalation of particulate matter released.
from on-site. soils: dermal contact with surface water and subsequent
contaminant absorption: and human inges~ion of fish. The exposure
pathway considered to be of most concern to aquatic life was
exposure to water in direct contact with sediments contaminated
with PCBs..
Under potential site development conditions (i.e., development
as a residential area), four exposure scenarios were evaluated:
ingestion of on-site groundwater: direct contact with on-site
soils7 and inhalation of volatile organic compounds and particulate
matter released from on-site sQils.
'The potential human health risks estimated under present site
use-.cond.itions are summarized in Table C-2. Potential risks were
estimated for children who may occasionally play in the soils at
or near the Re-Solve site. Exposures and risks were evaluated
for all the hunan health indicator chemicals detected in the
soils. Exposure to the potentially carcinogenic human health
indicator chemicals found in the on-site surface soils may result
in potential upper bound incremental lifetime cancer risks of
6x10-8 for the average case and 4xlO-S for the plausible maximum
case. Incremental lifetime cancer risks posed by exposures to
.off-site surface soils could be as high as 5xlO-8 under average
exposure conditions and 8xlO-S under plausible maximum exposure
conditions. The compounds contributing most to these risks were
PCBs. The estimated exposures to the non-carcinogenic indicator
chemicals in both on- and off-site soils were below chronic
intake levels of concern.
The potential risks associated with inhalation of volatile organic
compounds and particulate matter released from the soils at the
Re-Solve site were evaluated. The incremental lifetime cancer'
risks associated with the inhalation of volatiles released from
soils may be as high as 9xlO-9 for the average exposure conditions
and lxlO-6 for the plausible maximum exposure conditions. Exposure
to chemicals present in suspended particulate matter were associated
with upper bound lifetime cancer risks of 8xlO-11 for the average
exposure scenario and 7xlO-8 for the plausible maximum exposure
scenario. The risks from inhaling particulate matter were
associated with the inhalation of PCBs. Exposure to volatile
organic compounds released from the Copicut River was evaluated.
These exposures were estimated to result in excess lifetime
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cancer risks of up to 2xlO-7 for the average exposure scenario.
and 5xlO-6 for the plaUSible maximum exposure scenario. The
estimated exposures to the non-carcinogenic indicator'chemicals
released from both soils and surface water were below the chronic
intake levels of concern.
The potential risks to individuals who may occasionally wade in
the Copicut River adjacent to the Re-Solve site area and have
dermal contact with contaminants in the river were assessed. The
incremental lifetime cancer risks may be as much as 9x10-9 under
average exposure conditions and lXlO-6 under plausible maximum
exposure conditions. Dermal contact with the non-carcinogenic'
indicator chemicals detected in the Copicut River and the unnamed
tributary was estimated to result in exposures well below the
human health reference doses.
The potential risks associated with ingestion of PCB-contaminated
fish were a-Iso evaluated. For an individual assumed to regularly
ingest American eels caught near the site, incremental lifetime
cancer risks were estimated to range from 7xlO-4 to 8xlO-3 under
average and plausible maximum exposure scenarios, respectively.
The excess lifetime cancer risks associated with ingestion of
other less contaminated fish seecies were estimated to range from
4x10-4 to 7xIO-6. '
If the site were developed in the future (i.e., as a residential
areai, excess risks would be associated with each of the hypothe-
tical pathways considered: ingestion of on-site groundwater,
ingestion of and direct dermal contact with contaminated soils,
and inhalation of volatile compounds and pa~ticu~ate matter
released from contaminated on-site soils. The potential human
health risks associated with exposures under future site use
conditions are summarized in Table C-3.
,
Based on a comparison with standards and guidelines for drinking
water and the quantitative risk assessment (Supplemental RI,
1987), the contaminants in groundwater at the site would pose
significant risks if unfiltered drinking water was obtained from
an on-site well. The average and maximum unfiltered sample
concentrations for the human health indicator chemicals were
compared with standards and guidelines for drinking water as
shown in Table C-4. The geometric mean contaminant concentrations
for unfiltered groundwater at'the site exceeded the HCLs for
lead, trichloroethylene and vinyl chloride and exceeded the
proposed MCLG for cadmium.
For each chemical except arsenic, the maximum unfiltered concen-
trations exceeded the standards and proposed values shown in
Table C-4. Results for a set of filtered groundwater samples are
also provided in Table C-4. The inorganic compounds were detected
less frequently in the filtered samples than in the unfiltered
samples, suggesting that they are predominantly associated with
suspended sediment in groundwater.
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The concentrations of the selected indicator chemicals measured
in on-site unfiltered groundwater samples were used to evaluate
the potential risks associated with ingestion of groundwater.
The incremental lifetime cancer risks for ingestion of the human
health indicator chemicals ranged from 4xlO-3 to 5xlO-l under
average and plausible maximum exposure conditions, respectively.
These risks were primarily attributable to the ingestion of vinyl
chloride. Chronic ingestion of the non-carcinogens; cadmium,
trans-l,2-dichloroethylene, and ~ead at the levels measured in
unfiltered on-site groundwater would also pose a hazard to
potential well-water users.
For an individual assumed to incidentally ingest and have dermal
contact with on-site soils under the future site development
scenario, the estimated average and plausible maximum exposure
conditions were associated with incremental lifetime cancer risks
of lxlO-7 and 3xIO-2, respectively. Exposure to PCBs in soils
accounted for the major portion of the estimated risks. For the
non-carcinogenic indicator chemicals, chronic incidental ingestion
of cadmium and lead under the plausible maximum exposure conditions
could also pose risks to human health.
Inhalation of volatile organic-, compounds released from the Re-Solve
site soils under future site use conditions was estimated to
result in incremental upper bound lifetime cancer risks of 3xlO-5
anda3xlQ-4 for the average and plausible maximum exposure
scenarios, respectively. Inhalation of chemicals adsorbed to
suspended particulate matter was estimated to result in excess
upper bound lifetime cancer risks of 3xlO-7 for the average
exposure case and 2xlO-5 for the maximum exposure case. Inhalation
exposures to non-carcinogenic indicator chemicals were estimated
to be below chronic intake levels of concern.
Finally, PCB contaminated sediments near the
likely to adversely affect sediment-dwelling
also impact animals at higher trophic levels
Re-Solve site area as a habitat.
Re-Solve site are
organisms and may
that depend on the
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III
Enforcement
In 1983, EPA obtained copies of the Re-Sqlve, Inc. business files.
Based upon a review of these files, EPA identified 270 Potential
Responsible Parties (PRPs) and sent a combination notice/information
request letter to each PRP during Hay/June of 1983. Besides
notifying each PRP of their potential liability in relation to the
site, EPA requested that each PRP submit all records pertaining to
business transactions with Re-Solve, Inc. Following the receipt
of information request responses, EPA narrowed the list of PRPs
to 240 and developed a comprehensive volumetric ranking list.
In 1983, EPA initiated negotiations with the PRPs for past costs
and performance of the recommended remedy identified in the on-site
RI/FS. The preferred remedy was for the excavation of
sources of contamination (i.e., four waste lagoon areas, oil
spreading area and other Mhot spotsM), treatment and transportation
to an off-site disposal facility and encapsulation of the site.
Negotiations ceased when EPA informed the generators' committee of
EPA's increased estimate of the amount of soil requiring excavation.
EPA then proceeded to use the Superfund Trust Fund to perform
the remedy.
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On Hay 3, 1985, EPAheld a meeting with the PRP negotiating
committee to discuss the off-site RI/FS. At the onset of the
meeting, "EPA informed the PRPs that further additional contaoination
had been discovered on-site. EPA indicated it would terminate
the construction contract with the COE, it would not encapsulate
the site and a Supplemental RI would be performed to determine
the ex:~ent of contamination. As a result of this information,
negotiations ceased.
During the performance of the remedial work for the Supplemental
RI and the development of the FS, EPA conducted briefings for the
PRPs.
In March of 1987, following release of the Supplemental RI, EPA
discussed the FS development strategy for the site with the PRPs.
In June of 1987, immediately prior to release of the Agency's
Proposed Plan for site remediation, EPA met with the PRPs and a
representative of the Town of Dartmouth and discussed that plan.
Finally, during the public Comment period, EPA met with the
PRP's technical sub-committee and discussed technical issues.
. As a result of this meeting, the Agency provided the PRPs with
additional technical information to clarify certain studies and
calculations presented in the FS. Further negotiations with the
PRPs will be held following issuance of this ROD.
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-17-
IV.
Community Relations
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Throughout the implementation of the source control remedial
action and the conduct of the RIfFS, EPA promoted a Cooperative
working relationship with the town of Dartmouth by communicating
relevant information to the Hazardous Waste Coordinator for the
Town on a regular basis. In addition, the Hazardous Waste
Coordinator attended technical meetings held between EPA and the
PRPs Technical SUb-committee.
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On March 11, 1987, EPA held a public. meeting to discuss the
project schedule, the findings ~f the RI and the preliminary'
list of remedial alternatives under development in the FS. The
public was primarily concerned with the quality of drinking
water in the area and PCB contaminated fish. EPA informed the
public that the elevated lead detected in certain wells was not
attributahle to the site and that those persons affected should
coordinate with MA DEQE. Overall, the drinking water in the
area is of acceptable quality. EPA also re-emphasized the need
for public participation in the remedy selection process.
During the development of the FS, the Westport River Defense
Fund (WRDF) and a local citizens group, Precinct One North
Dartmouth (P.O.N.D.) worked cooperatively to form a Citizen's
Advisory Committee (CAC) for the site. EPA and MA DEQE assisted
in ~he organization of the CAC and met with the group during the
remedy selection process. During this meeting, EPA and MA DEOE
assured the group that they would be available to meet during
the design and construction phase.
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The FS for the site was released to the public for review and
comment on June 2, 1987. Consistent with Section 117 of CERCLA,
EPA published a preferred remedial action document on June 17, 1987
describing the Agency's proposed plan for site remediation.
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Release of the document initiated
during which the public was given
on the proposed plan and the FS.
to close on July 7, 1987.
EPA held a public information meeting to discuss the proposed
plan and FS on June 23, 1987,. During the meeting, the public
requested EPA to extend the public comment period. In response
to both oral and written requests by members of the public and
the PRPs, EPA extended the public comment period to July 31, 1987.
a 21 day public comment period
an opportunity to submit comments
The comment period was scheduled
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A public meeting was held on July 1, 1987, allowing the public
the opportunity to enter oral comments into the record. These
comments were recorded in a transcript which is part of the
Administrative Record for the site. Written and oral comments
and EPA's responses are included in. the Responsiveness Summary.
A number of commenters (the Sierra Club, Town of Dart~outh,
Re-Solve Citizen's Advisory Committee (CAC), and Westport River
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Defense Fund, (WRDF» supported EPA's-choice of dechlorination
with groundwater t~eatment as the preferred alternative for the
Re-Solve site. Several comrnenters (the Sierra Club, WRDF) noted
that Region I deserves commendation in deciding on an innovative
technology. The Sierra Club also supported the identification of
incineration as the backup option.
Citizens and the Town of Dartmouth expressed interest in being
kept appraised of any n~w information EPA receives on the dechlor-
ination process. In addition, the public would like the opportunity
to review and discuss the results of the pilot-study.
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Alternatives Evaluation
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A.
Introduction
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On October 17, 1986, the President signed into law the Super-
fund Amendments and Reauthorization Act of 1986 (SARA) amending
the Comprehensive Environmental Response, Compensation and Liability
Act of 1980 (CERCLA) and enacting certain additional provisions.
Prior to SARA's enactment, actions taken in response to releases
of hazardous substances were conducted in accordance with the
revised National Oil and Hazardous Substances Pollution Contingency
Plan (NCP), 40 C.F.R. Part 300 dated November 20, 1985. Generally,
the purpose of the NCP is to effectuate the response powers and
responsibilities created by CERCLA. In accordance with Section 105
of CERCLA as amended by SARA, the existing NCP is being revised
to reflect the additional provisions of SARA.
While the existing NCP and the standards and procedures estab-
lished by SARA overlap in many areas, there also exist some
differences between the two. Section 121 of SARA, for example,
added certain new clean-up objectives to CERCLA. In the interim,
until the NCP is republished, the procedures and standards employed
by the Agency in responding to" releases of hazardous substances,
pollutants, and contaminants are to comply with section 121 of
CERCLA and, to the maximum extent practicable, the existing NCP.
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SARA retained the original CERCLA mandate to conduct protective
and cost-effective remedial actions. Remedial actions. as
defined by 300.68(a)(1) of the NCP are those responses to releases
that are consistent with a permanent remedy to protect or minimize
the release of hazardous substances or pollutants or contaminants
so that they do not migrate to cause substantial danger to present
or future public health or welfare or the environment.
In formulating a remedy, CERCLA now requires the Agency to place
heightened emphasis on risk reduction through destruction or
treatment of hazardous waste. Section 121 'of establishes a
statutory preference for remedies that permanently and signi-
ficantly reduce the volume, toxicity and mobility of hazardous
wastes over remedies that do not use such treatment. Section 121
, also requires that EPA select a remedy that is protective of
human health and the environment, is cost-effective and that
utilizes permanent solutions and alternative treatment technologies,
to the maximum extent practicable. Furthermore, section 121
requires that, upon completion, remedies must attain applicable
or relevant and appropriate Federal and State requirements (ARARs)
unless specified waivers are granted.
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In accordance with CERCLA and the NCP, therefore, the primary
remedial response objectives for Superfund remedial actions
are:
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prevent or mitigate further releases of contaminants
to surrounding environmental media:
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Following the establishment of remedial objectives, the
next issue becomes establishing the appropriate procedures.
Again, the Agency must address the NCP and the procedures set up
in CERCLA.
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eliminate or minimize the threat posed to pUblic health
or welfare or the environment;
o 0 reduce the volume, toxicity or mobility of hazardous
waste through the use of treatment technologies; and
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utilize permanent solutions and alternative treatment
technologies or resource recovery technologies to the
maximum extent practicable.
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Section 300.68 of the NCP, in conjunction with the EPA guidance
document entitled MGuidance on Feasibility Studies Under CERCLA,"
sets forth the remedial alternative development and remedy selection
process. This process consists of seven steps:
Both CERCLA and the NCP require first the identification of the
nature and extent of contamination at the site. Beyond the
initial site characterization section 121 retains the basic
framework for the remedial alternatives development and remedy
selection process enacted through the NCP, but each phase must
be modified to reflect the provisions of CERCLA.
The nature and extent of contamination and the threat presented
by the release at the Re-Solve site was documented in the Remedial
Investigation for the site and presented as part of the discussion
on Site History. A discussion of how CERCLA affects each particular
phase of the remedy selection process (Steps 2-7) follows.
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B.
Identify the nature and extent of contamination and threat
presented by the release (5 300.68(e)(2»;
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Identify general response objectives for site remediation;
Identify and screen remedial technologies potentially
applicable to wastes and site conditions;
Develop alternatives to achieve site-specific response
objectives (5 300.68,(f»;
Initial screening of alternatives (5 300.68(g»;
Detailed analysis of alternatives (5 300.68(h»; and
Selection of remedy (5 300.68(i».
Response Objectives
Consistent with the NCP, remedial response objectives for the
Re-Solve site were developed for source control measures, which
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aQdress source areas of contamination, and management of migration
measures, which address media or areas that have been impacted
by the migration of contaminants away from the source area.
The ReMedial Investigation identified four sources of contam-
ination at the site. 'Those sources are the soils in the vicinity
of the former lagoon area, the cooling pond area, the oil spreading
area and localized areas which include the contaminated sediments
~ocated in the wetlands north of the site and the unnamed tributary. .
On-site areas with PCB contamination above 10 ppm consist of
2.,000 cubic yards (c.y.) of unsaturated soil and 37,000 c.y. of
saturated soil. The wetlands and the unnamed tributary have
3,000 c.y. of contaminated sediments above 1.0 ppm PCB. The
total volume of such source material is 64,000 c.y. The average
surface soil contamination level for PCBs is 140 ppm. The
wetlands and unnamed tributary have an average surface PCB,
contamination of 24 ppm. (Handling of contaminated liquids resulting
from dewatering and treatment of soils and sediments are included
in the management of migration alternatives for groundwater).
The remedial response objectives for source control measures
include:
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Prevent or mitigate the continued release of hazardous
~ubstances, pollutants and contaminants to the over-
burden and bedrock groundwater aquifers and to the wetlands,
the unnamed tributary, Copicut River and Cornell Pond.
Reduce risks to human health associated with direct
contact with contaminants in surface and sub-surface
soils and sediments. '
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Reduce risks to freshwater aquatic life associated with
contact with PCB contaminated sediments and subsequent
bioaccumulation. Freshwater aquatic life include both
sediment dwelling organisms and those at higher trophic
levels.
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Reduce the volume, toxicity or mobility of hazardous
substances, pollutants and contaminants.
The R,medial Investigation also determined that the four source
areas have contaminated on and off-site groundwater and off-site
surface water. Remediation of cont~minated groundwater is necessary
to address surface water contamination, since the source of
contamination in surface water bodies 1s groundwater discharge.
Treatment of groundwater would include treating contaminated
liquids resulting from dewatering and treatment of on-site source
soils. In addition, it is known, based on the previous remedial
action undertaken at the site, that extensive on-site activity
may result in increased airborne contamination. The remedial
response objectives for the management of migration measures
include: ,
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Reduce risks to human health associated with dermal
contact and Subsequent absorption with surface water,
ingestion of groundwater and inhalation of volatiles
released from groundwater ~nd surface water.
Elimtnate or minimize the threat posed to public health
and the environment from the current and potential
future extent of contaminant migration in groundwater
and surface water.
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Maintain air quality at protective levels for on-site
workers and the public during site remediation.
Technology Development and Screening
General response actions, identified as response categories
in the FS, represent a group or class of responses that could
potentially meet the remedial objectives. Technologies
identified for each response category were screened based on
waste-limiting (waste characteristics that limit the effec-
tiveness or feasibility of a technology) and site-limiting
(site characteristics such as .high groundwater levels that
preclude the use of certain technologies) factors unique to
the Re-Solve site, and the level of technical development
for each technology. Section 3 of the FS report details
thi~process.
Table C-S summarizes the general response categories and the
applicable technology screening for source control and manage-
ment of migration.
Technologies which emerged from this screening process were
combined into Source control and management of migration
alternatives. This process is detailed in Section 3 of the FS.
D.
Development of Alternatives an1 Initial Screening of
Alternatives
Section 300.68(f)(1) of the NCP requires that, to the extent
that it is both possible and appropriate, at least one remedial
alternative shall be developed as part of the Feasibility Study
in each of the fOllowing categories:
.
Alternatives for treatment or disposal at an off-site
facility as appropriate.
Alternatives that attain applicable or relevant and
appropriate Federal public health and environmental
requirements.
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As appropriate, alternatives that exceed applicable or
relevant and appropriate Federal public health and
environmental requirements.
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-23-'
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As appropriate, alternatives that do not attain appli-
cable or relevant and appropriate Federal public health
and environmental requirements but that will reduce the
likelihood of present or future threat from hazardous
substances and that provide significant protection to
public health and welfare and the environment. -This
must include an alternative that closely approaches the
level of protection provided by alternatives that attain
applicable or relevant and appropriate requirements.
No action alternative.
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This screening of alternatives must also comply with the require-
ments of section 121 of CERCLA. Of most importance, section l2l(d)
codifies the CERCLA Compliance Policy. First published as an
appendix to the preamble of the NCP, this policy requires that
Superfund remedial actions attain applicable or relevant and
appropriate requirements (ARARS) of other Federal statutes.
While Section 300.68 (f) of the NCP specifically refers to ARARs
in regard to the Development of Alternatives, section 121 incor-
porates this requirement into the statute while adding the provision
that remedial actions also attain State requirements that are
more stringent than Federal requirements, to the extent they are'
also applicable or relevant and appropriate and are identified
to EPA in a timely manner. Further, the new statutory requirements
and~reference for treatment that reduces the volume, toxicity
or mobility of hazardous was~e, modify the process by which
alternatives are developed.
In accordance with CERCLA, and to the e~tent practicable, the NCP,
treatment alternatives were developed for the Re-Solve site
ranging from an alternative that, to the degree possible, would
eliminate the need for long-term management (including monitoring)
at the site to alternatives involving treatment that would reduce
the volume, toxicity or mObility of the hazardous substances as
their principal element. The alternatives arrayed along the
scale vary mainly in the degree to which they rely on long-term
management of treatment residuals or low-concentration wastes.
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In addition to the range of treatment alternatives, a containment
option involving little or no treatment and a no action alternative
were developed. Alternatives developed and considered for initial
screening at the Re-Solve site are:
Source Control
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SC-4
SC-5
SC-6
SC-7
No Action
On-Site Thermal Destruction
Soil Washing
Dechlorination
Composting
Immobilization
In-Situ Biodegradation
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Source Control
SC-8
SC-9
SC-lO
SC-ll
SC-l2
SC-l3
SC-14
In-Situ Soil Flushing
Encapsu'lat ion
On-Site RCRA/TSCA Landfill
Sediment Capping
Sediment Removal And Treatment
Off-Site RCRA/TSCA Landfill
Off-Site Incineration
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MOM-2A
No Action (with monitoring)
On-Site Treatment, as follows:
Precipitation/Heated Influent
Air Stripping/Filtration
Precipitation/Filtration/Carbon Adsorption
Precipitation/Air Stripping/Filtration/
Carbon Adsorption
Precipitation/Air Stripping/Biodegradation/
Filtration/Carbon Adsorption
Off-si te... treatment at a RCRA Treatment/Storage/
Disposal (TSD) Facility
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MOM-2C
MOM-2D
MOM-3
~OM-4
Pretreatment (Air Stripping) and Disposal
Off-site at a Publically Owned Treatment
Works (POTW)
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The purpose of the initial scr~ening step is to reduce the number
of alternatives for further detailed analysis while preserving a
range of options. The range of alternatives developed for source
control and management of migration were subject to an initial
screening using the criteria listed in 300.68 (g)(l), (2) and (3)
of the NCP. Even if an alternative does not pass the initial
screening under the NCP, consistent with section 121 (b)(2) an
alternative may be carried through the screening process if it
. involves an innovative technology and there is a reasonable belief
that it offers a potential for better treatment performance or
implementability, or fewer or less adverse impacts than other
available approaches or lower costs than demonstrated technologies.
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The results of the initial screening process are described in
detail in Section 3 of the FS. The initial screening process
eliminated the following alternatives based upon the specified
deficiencies for the reason(s) indicated: .
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SC-3
Soil Washing
300.68(g)(3): alternative does not effectively Contri-
bute to the protection of public health and welfare and
the environment.
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Composting
300.68(g)(2): alternative is not feasible for the
location nor does it represent a reliable means of
addressing the problem. Technically ineffective and not
feasible based on site characteristics.
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of material would do~ble or triple.
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Immobilization
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contaminants.
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300.68(g)(3): alternative does not effectively contribute
to the protection of public health and the environment.
SC-7
In-Situ Biodegration
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for the location and conditions of the release.
SC-8
In-Situ Soil Flushing
300.68(g)(2); not feasible based on location and
conditions of the release and does not meet acceptable
engineering practices for reliability.
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300.68(g)(3); questionable effectiveness and adverse
environmental impacts.
Encapsulation
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protection of public health and welfare and the
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As individual specific alternatives, SC-7, SC-8 and SC-g would not
provide adequate levels of remediation. However, because of the
extensive excavation of contaminated soils and associated technical
limitations, potential health risks and costs required for other'
. Source control alternatives, these three technologies were grouped
together as a single remedial alternative for detailed analysis,
to be referred to as SC-7, In-Situ Treatment.
SC-IO On-Site RCRA/TSCA Landfill
300.68(g)(2)1 technically infeasible for the location
and conditions of the release and not' a reliable
means of addressing the problem.
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300.68(g)(3)1 questionable effectiveness.
SC-ll Sediment Capping
SC-13 Off-Site RCRA/TSCA Landfill
300.68(g)(1)1 No substantially greater public health
. and environmental benefits at a greater cost than other
source control alternatives. Limited availability and
limited capacity. '
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significant adverse effects and very limited environ-
mental benefits.
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On-Site Treatment by precipitation/Filtration/Carbon
Adsorption
300.68(g)(1)1 no substantially greater public health
and environmental benefits at a greater cost than
other on-site treatment.
300.68(g)(3)1 questionable effectiveness.
On-Site Treatment by Precipitation/Air Stripping/
Biodegradation/Filtration/ Carbon Adsorption.
300.68(g)(1)1 no substantially greater public health
and environmental benefits at a greater cost than
other on-site treatment.
Off-Site RCRA TSD Facility
300.68(g)(1)1 no substantially greater public health
or environmental benefits with greater costs.
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'management of migration alternatives can be. seen in Tables C-6 and
C-7, respectively.
Consistent with the NCP, a No Action alternative for both Source
control and management of migration was carried into the detailed
analysis to provide a basis for comparison to the other alterna-
tives although it would probably not achieve the requirements of
section 121 of CERCLA. In addition, a containment option, SC-9,
Encapsulation, was retained for detailed analysis as a component
of the canprehensive In-Situ Treatment alternative.
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for a more detailed evaluation.
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Detailed Analysis of Alternatives
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The alternatives evaluated during detailed review and screening
include both source control and management of migration alter-
natives:
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SC-2
SC-4 .
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No Action
On-Site Thermal Destruction
Dechlorination
In-Situ Soi1 Treatment 2
SC-7a Encapsulation
SC-7b Encapsulation with In-Situ Soil Flushi~g
SC-7c Encapsulation, In-Situ Soil Flushing and
Source Material Treatment
Off-Site Incineration
Management of Migration
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On-Site Treatment
MOM-2a Heated Influent Air Stripping
MOM-2c Carbon Adsorption
Pre-treatment and Disposal at a POTW
A detailed analysis of the five (5) source control and three (J)
management of migration alternatives was conducted consistent
. with section 121 of CERCLA and, to the maximum extent practicable,
40 C.F.R. S JOO.68(h) of the NCP.
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The evaluation criteria cited in section 121(b)(1)(A-G) are:
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the long-term uncertainties associated with land diposal:
the goals, objectives and requirements of the Solid Waste
Disposal Act:
the persistence, toxicity, mobility and propensity to
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bioaccumulate of such hazardous substances and their
constituents;
( D)
short- and long-term potential for adverse health effects
from'human exposure;
(E)
(F)
long-term maintenance costs;
potential for future remedial action costs if t.he alter-
native remedial action in question were to fail; and
the potential threat to human health and the environment
associated with excavation, transportation and re-disposa1
or containment.
For alternatives where treatment is the princi-pal component of
the alternative, several of the section 121 (b) (1) factors are
not relevant since treatment will destroy the contaminants, or
reduce them to protective levels. The fOllowing section l2l(b) (1)
factors do not have significance when evaluating treatment alter-
natives since treatment elimina~~s landfilling:
(A)
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( E)
the long-term uncertainties associated with land disposal;
and
long-term maintenance costs
Furthermore, by considering as factors, section l2!(b) (1) (A)and(c)
inherently the Agency incorporates section l2l(b) (1) (8), thereby
meeting goals, objectives and requirement of the Solid Waste
Disposal Act.
The potential for future remedial action costs, if the alternative
remedial action in question were to fail, (section l2l(b) (1) (F»
is an important evaluation factor for alternatives that require
long-term maintenance and monitoring. This factor was used when
evaluating land disposal alternatives. The inability of a treatment
technology to obtain its performance goals (i.e. fail) would
most probably result 1n 8electio~ of a different remedial action
or a change in performance goals; hence the potential costs
associated with failure of a treatment technology were not evaluated
. for each sucb alternative. Potential failure of a technology may,
though, be incorporated into a selected remedy in the event that
the remedy is innovative and has not been proven on a fUll-scale
level or in similar situations.
The initial screening OCcurs under the requirement of section 121.
Following a review of the section 121 factors, the Agency considers
the NCP factors in screening. The evaluation criteria cited in
40 C.F.R. 300.68(h) of the NCP are:
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costs, and distribution of costs over time;
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( 2 )
Evaluation in terms of engineering implementation,
reliability, and constructabilitY1 .
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An assessment of the extent to which the alternative is
expected to effectively preven~, mitigate, or minimize
threats to, and provide adequate protection of, public
health and welfare and the environment. This includes
an evaluation of the extent to which the alternative,
attains or exceeds applicable or relevant and appropriate
federal public health and environmental requirements.
Where the analysis determines that federal public health
and environmental requirements are not applicable or
relevant and 'appropriate, the analysis, as appropriate,
evaluates the risks of the various exposure levels
projected or remaining after implementation of the
alternative under consideration1
An analysis of whether recycle/reuse, waste minimization,
waste biodegration, or destruction, or other advanced,
innovative, or alternative technologies is appropriate
to reliably minimize present or future threats to public
health or welfare or the environment:
.;..,
An analysis of any adverse environmental impacts, methods
for mitigating these impacts, and costs of mitigation.
The Agency's primary mandate" however is to meet the requirements
of section 121: alternatives undergoing detailed analysis will
be evaluated in terms of the section 121 (b)(l) (A-G) factors.
\lhere it was determined that an alternative is consistent with the
. NCP, the alternative was further evaluated using the appropriate
40 C.F.R. 300.68(h) factors.
Source control and management of migration alternatives are
evaluated in detail in Section 4 of the FS.
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SC-I and MOM-I No Action
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For the purposes of the detailed evaluation, the no action alter-
native for source control (SC-I) and management of migration
(MOM-I) were combined and evaluated as a comprehensive no action
alternative.
The no action alternative for the Re-Solve site consists of under-
taking minimal actions to limit the potential risks posed by the
site to public health and the environment. These actions include
fencing the perimeter of the site, posting warning signs on the
fence and in the area of the unnamed tributary, Copicut River
and Cornell Pond, grading the site towards the wetlands and
unnamed tributary: loaming and seeding to ~ontrol dust and imple-
menting a multi-media monitoring program. The monitoring program
includes air, groundwater and surface water sampling. Air samples
would be taken during revegetation and grading operations, as well
as necessary control measures, to ensure that on-site operations
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do not pose health risks to on-site workers and nearby residents.
The groundwater, surface water and'sediment monitoring program
would extend for thirty (30) years after the closure of the site.
This program would include sampling of both the overburden and
bedrock aquifers as well as su'rface water and sediments in the
wetlands, the unnamed tributary, Copicut River and Cornell Pond
on a regular basis.
The no action alternative does not meet the goals, objectives
and requirements of the Solid Waste Disposal Act. Specifically,
this alternative does not assure long-term containment of the
hazardous wastes at the site and, therefore, does not preclude
the need for' future corrective action.
Further, the no action alternative would not permanently and
significantly reduce the vOlume, toxicity or mobility of the
hazardous wastes at the site. PCBs are both probable human car-
cinogens and chemically stable compounds that are able to persist'
in the environment for long periods. PCBs can significantly
bioaccurnulate and concentrate in the fatty tissues of all organisms.
If left untreated, as proposed in the no action alternative, PCBs
in sediments will continue to act as a Source of contamination
with subsequent bioaccumulation for benthic organisms and organisms
at higher trophic levels. In addition, precipitation at the site
would continue to leach mobile contaminants such as VOCs from the
source areas into groundwater. The FS estimates it would take 175
to 400 years for contaminant levels in Source areas and groundwate'
to be reduced, through natural attenuation and biodegradation
processes, to levels that are protective of hUDan health and the
. environment. PCBs, in both the unsaturated and saturated zones
would remain at current levels indefinitely. Over this period
of time, contaminated groundwater would continue to discharge to
the unnamed tributary and Copicut River and migrate away from
the site via surface water.
Fencing the site under the no action alternative would reduce
the risks posed to public health from direct contact with on-site
soils, but would not mitigate the risks posed from direct contact
with off-site soils and sediments.
The fence and ground cover can easily and rapidly be installed at
the site and a low level of effort is required to maintain the
integrity of the fencing and 'grOund Cover over its 30 year life.
Operation and maintenance would include fence repair and replace-
ment of the fence in 15 years and implementation of the multi-media
monitoring program.
Furthermore, the no action alternative does not attain Federal and
State applicable or relevant and appropriate public health and
environmental requirements. Specifically, it does not comply
with the Resource Conservation and Recovery Act (RCRA) 40 C.F.R.
Part 264, Subparts G (Closure and Post Closure), K (Surface
Impoundment Regulations), L (Waste Piles) and N (Landfills) and
Executive Order 11990 (Wetlands).
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The. estimated capitol cost for the no action alternative is
$178,000. The annual operation and maintenance (0 , H) cost is
estimated to be $152,000. The present worth for the no action
alternative, assuming a 10 percent discount rate, is estimated to
be $1,640,000.
SC-2 On-Site Thermal Destruction
..
The On-site Thermal Destruction alternative entails excavation of
6'4,000 cubic y'ards of PCB contaminated soils and s~diments
(61,000 c.y. of soil> 10 ppm.and 3,000 c.y. sediments> 1 ppm)
and treatment on-site in a mobile incineration system. This
volume was selected for engineering purposes only and may vary
depending upon the soil cleanup level selected for the site.
The soil boring program conducted as part of the Supplemental RI
indicated that the bulk ~f the PCB contaminated soils are located
in the northwest portion of tbe site. In this area, PCBs at
levels greater than.lO ppm were found in soils overlying bedrock,
approximately 20 feet below the water table.
Treatment of the 64,000 cubic yards of contaminated soils and
sediments will require extensive on-site handling and processing
of soils throughout the site. .;..In an effort to mitigate the
potential offsite migration of contaminated fugitive dust and
odors, the method of excavation will be restricted to sheet
pileJ vertical cuts. When excavating below the water table, it
will be necessary to pu~p the enclosed area. The purpose of
this approach is to reduce open air removal of contaminated
soil, and thus, limit potential emissions. Additionally, these
emissions can be controlled by a number of methods, including
enclosure of the work areas and emission suppression techniques
such as foam or water spray method for dust control.3
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Implementation of this alternative also requires excavation of
PCB-contaminated sediments and relocation on-site for subsequent
treatment in a mobile incineration system.4 For the purposes of
this evaluation, it is estimated that it will be necessary to
excavate and treat approximately 3000 cubic yards of PCB contam-
inated sediment containing> 1 ppm PCB. (As noted earlier,
this volume is included in the total volume of 64,000 cubic
yards and may change depending on the sediment cleanup leve~
selected for the site). Thes, sediments are located in areas
classified as wetlands, based on National Wetlands Inventory
(NWI) mapping as well as site visits to confirm wetland boundaries.
Host of the area, which includes the wetlands north of the site
and the unnamed tributary, is characterized as a palustrine
forested (red maple) or palustrine scrub shrub. Excavation in
these areas, therefore, will result in unavoidable impacts and
disturbance to wetland resource areas. Such impacts may include
the destruction of vegetation and the loss of certain plant and
animal species. Impacts to the fauna and flora will be mitigated
to the maximum extent possible. All excavation activities will
be conducted during dry weather periods and excavated areas will
be isolated by means of erosion and sedimentation control devices
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'to limit the resuspension and downstream transport of contaminated
material. Following the excavation activities, all disturbed
. areas will be restored to their approximate original condition
including any necessary revegetation.
Three potentially applicable thermal treatment technologies were
presented in the FS for detoxification of the contaminated soils
and sediments. These technologies are rotary kiln incineration,
infrared processing and circulating fluidized bed incineration.
All are currently available as mobile systems for on-site hazardous
waste treatment. These three technologies offer different capa-
bilities for the wide range of contaminants encountered at CERCLA
sites. While rotary kiln incineration handles the broadest range
of volatile types and forms, infrared processing and fluidized.
bed incineration consume less air and offer advantages in pollution
control, residual disposal and cost. All three technologies have
been proven at least on a pilot-scale, to be effective in
de~troying P~Bs in soils similiar to those found at the site.
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The evaluation of the On-site Thermal Destruction alternative
indicates that such treatment of 64,000 cubic yards of contaminated
soils and sediments will permanently and significantly reduce
the volume, toxicity and mobility of the hazardous wastes present'
at the site. The analytical screening of the s01l samples at
Re-Solve, Inc. reveal high levels of both PCBs and volatile organic
com~ounds. To comply with 40 C.F.R. 5761.70 of TSCA, a selected
incineration system must demonstrate a 99.9999 percent destruction
and removal (DRE) efficiency of PCBs. If the thermal destruction
alternative is selected, a trial burn would be cond~d or
required by 40~C.F.R. 5 761.70 to determine if the incinerator
achieves the requirements of TSCA. All systems generate residual/
effluent streams; ash, decontaminated soils, scrubber water or
blowdown and fuel gases.
During the trial burn, the Agency will identify the waste constit-
uents in the site-specific residual/effluent stream and determ~ne
the appropriate manner in which to dispose of such residuals.
The intent is to place decontaminated soils back on-site. Residuals
remaining on-site of after treatment would be those soils contam-
inated with PCBs at levels less than 10 ppm PCB and low levels of
volatile organic compounds, and sediment with less than 1 ppm PCB.
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Treatment of the PCB contaminated sediments will permanently and
significantly reduce the risks to benthic organisms and organisms
at higher trophic levels associated with contact with such sedi-
ments and subsequent bioaccumulation.
An air monitoring program will be implemented during the perfor-
mance of this alternative to monitor risks to on-site workers and
nearby residents. Mitigative measures, such as those discussed
previously, will be taken during excavation to control emissions.
The incinerator stack emissions will be closely monitored to ensure
that levels are in compliance with RCRA and TSCA. Treatment of
PCB contaminated soils will reduce the risks posed to public
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health from direct contact. In addition, the construction and
operation of the incinerator will generate some noise and traffic
impacts for local residents. Truck traffic to and from the site,
will increase, but the increase is not anticipated to be unreasonable.
It is. estimated that the length of operation will be approximately
two (2) years. The length of operation, though, may change depend-
ent on the cleanup level 'selected, which, in turn determines the
volume of contaminated soils that will be processed. FOllowing
,completion of this alternative, the site will be graded, loamed
and seeded.
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Although mobile incineration systems are commercially marketed,
there may be delays in getting a system on-site due to the present
limited capacity in the industry. Even though EPA anticipates
an increase in production in the future, there may be a problem
with availability. Mobile incinerators are presently being used
at various 'CERCLA sites and appear to be technologically reliable
based on data from full- and pilot-scale studies.
The On-site Thermal Destruction alternative attains all Federal
and State applicable or relevant and appropriate requirements.
Specifically, this alternative".will attain requirements under TSCA
which apply to PCB incineration, and RCRA requirements for incin~
eration of other organic compounds. All work conducted in area.
classified as wetlands will be in accordance with the following
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and Wetland Assessments for CERCLA Actions;
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o Federal Register 40 C.F.R Part 230, 404(b),December 24, 1980;
and
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(310 C.M.R. 10.00 !!. seQ.).
The cost analysis was based on rough cost estimates solicited from'
three companies offering incineration services. Based on these
estimates, a median value of $300/cubic yard was used for calcu-
lation of incineration costs.' The estimated capital cost for
this alternative is $21,315,400. The annual operation and main-
tenance (05") cost for this alternative in estimated to be
$5,778,000. The estimated present worth for treatment of 64,000
cubic yards of PCB contaminiated soils and sediments, assuming a
10 percent discount rate, is $31,347,000.
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A sensitivity analysis was conducted to determine how total
project ,costs change relative to different cleanup levels and
volume of treated soil. Costs were examined for six scenarios.
The total volume of contaminated material to be excavated, treated
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and disposed of was 13,000 c.y., 22,000 c.y., 28,000 c.y., 48,000
~.y., S6,000 c.y. and 64,000 c.y. The total project costs, pre-
sented in Figure C-14, are the present-worth value of the capital
costs and Operation and maintenance through the period of imple-
mentation.
SC-4 Dechlorination
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The Dechlorination 'alternative ent.ails excavation of 64,000 cubic
~ards of contaminated soils and sediments and treatment on-site
1n a. mobile dechlorination unit.6 Potassium/polyethylene glycol
(KPEG) dechlorination is a soil treatment process suitable for
treating large volumes of soil contaminated at low to moderate
levels (1 to 10,000 ppm) of chlorinated organics such as PCBs. .
Higher concentrations of PCBs can be treated but reagent costs
increase significantly. The KPEG dechlorination process rapidly
dechlorinates aromatic halides (this includes ch10robenzenes,
chlorophenols, dioxins, PCBs an~ other halogenated ring compounds).
The process, shown in Figure C-lS, is similar to a soil washing
system, with a reagent-soil contacting step followed by a multi-
step water rinse process.
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The evaluation of the Dechlorination alternative indicates that
treatment of 64,000 cubic yards of contaminated soils and sediments
will permanently and significantly reduce the volume, toxicity
or ~obility of the hazardous wastes present at the site. The
dechlorination process is primarily for the treatment of chlorinate"
organics such as PCBs. Bench-scale testing of the dechlorination
process was conducted to determine its effectivness in trearing
PCB contaminated soils. The initial concentration of soil samples
taken from the site were 3000 ppm PCB on average. The dechlorination
reaction reduced the PCB concentration to less than 1 ppm,
demonstrating that the process is effective for treatment of
Re-Solve soils.
In addition to PCBs, the Re-Solve soils are also contaminated
with other organic compounds. Results of the bench-scale study
indicate that dechlorination is effective in removing a percentage
of these compounds. In the process, contaminated soil is mixed
with a reagent mixture and heated to lSO. C. Heating to lSOo C
significantly increases the reaction rates for dechlorination and
boils off the water and many.volatile organics held within the
soil. The volatile organics, in turn, are captured in vapor
phase carbon. When the carbon is spent, it is disposed of off-
site in accordance with RCRA. The bench-scale study did not de-
termine the concentration and percentage of organic compounds
remaining in soils. Following treatment, the inte~~ is to place
the treated soils on-site.
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treatment and/or management will be determined in a pilot-scale
test, if dechlorination is selected as the final remedial action.
The dechlorination proce.ss also produces various residuals and
sidestreams such a spent reagent and contaminated wash water.
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Characterization of the reaction byproducts was beyond the scope
of the bench-scale study and would have involved a great deal of
analytical chemistry.
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However, because the major goal of the dechlorination process is
to convert materials that are harmful to living organisms to
materials that are harmless, EPAls Hazardous Waste Engineering
Research Laboratory (HWERL) in Duluth, Minnesota conducted bioassay
tests to determine the effects of the reaction byproducts on living
organisms. Such tests included: mutagenicity assays, toxicity
studies and bioaccumulation/bioconcentration tests. These bioassays
indicated that the byproducts produced between the reagents and
the pollutants studied (including TCDD) do not bioaccumulate or
bioconcentrate. Further, they do not cause mutagenicity nor are
they toxic to aquatic organisms or mammals. In any event, it
will be necessary to characterize these sidestreams during the
pilot-scale test to determine the proper manner in which to
dispose of these byproducts.
An air monitoring program will be implemented during the performance'
of this alternative to reduce risks to on-site workers and nearby
residents. Mitigative measures, such as those discussed in the
evaluation of alternative SC-2;. will be taken during excavation
to control emissions. Dechlorination systems are considered
relatively safe, and because the reactions occur within a closed
sys~m, the risks to nearby residents from the process itself are,
minimal. Other impacts asso~iated with construction and operation.
of the facility are similar to that of alternative SC-2 (i.e.,
noise, truck traffic). This alternative will effectively reduce
the risks posed to public health from direct contact with PCB
contaminated soils. The risks posed to public health from direct
contact with organic compounds present in soils following treatment
is expected to be minimal.
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It is estimated that the length of operation will be approximately
three (3) years. The length of operation may change dependent
on cleanup level selected for the site. Following completion of
this alternative, the site will be graded, loamed and seeded.
The reliability of this alternative on a full-scale level remains
unproven. Current data are only available for bench-scale and
limited pilot study tests. While the feasibility of the process
has been established, problems can be expected during scale-up to
full-scale operation. EPA is aware of one company that is planning
on building a full-scale dechlorination unit using heavy industrial
equipment by the spring of 1988. In 1985 EPA Region II selected
dechlorination as the remedial action for the Wide Beach Superfund
site, ,and that project is now in the design phase. EPA anticipates
that additional companies will acquire the capability to design
and construct dechlorination units in the future.
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applicable or relevant and appropriate requirements. Specifi-
cally, shipment of any residuals off-site for disposal will be in
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accordance with RCRA and DOT regulations 49 C.F.R 171-179 and 387.
In addition, final closure and post closure activities will be
consistent with RCRA 40 C.F.R. Part 264 Subpart G (Closure and
pos t Closure).
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The cost analysis was based on information ~rovided by the Galson
Research Corporation for treatment of various site volumes.
These unit costs were then incorpo~ated into the capital cost
and operation and maintenance costs. The estimated capital cost
for this alternative is $8,187,40b. The annual operation and
maintenance (O&M) cost is estimated to be $3,558,500. The esti-
mated present worth for treatment of 64,000 cubic yards of PCB
contaminated soils and sediments, assuming a 10 percent discount
rate, is $17,038,000.
A sensitivity analysis was conducted to determine how total
project cos~s change relative to different cleanup levels and
volume of treated soil. Costs were examined for six scenarios.
In the analysis, the total volume of contaminated materials to
be excavated, treated and disposed of was 13,000 c.y., 22,000 c.y.,
28,000 c.y., 48,000 c.y., 56,000 c.y. and 64,000 c.y. The total
project costs, presented in Figure C-16, are the present worth
value of the capital costs an~~operation and maintenance through
the period of implementation.
SC-7e
Enca sulation
Treatment
In-situ Soil Flushin
and Source Material
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Alternative SC-7c is comprised of three individual component
technologies. The first component, encapsulation, provides for
the in-situ containment. of the contaminated soils. A soil
bentonite wall consisting of a screened soil mixture with 6-8
percent bentonite at a 30-inch thickness and 10-7 em/see permea-
bility, will be constructed around the perimeter of the site.
The wall will extend from the surface and be keyed into the under-
lying bedrock. Once the wall is completed, all contaminated
soils found outside the perimeter, including wetland sediments,
will be placed inside the wall for further treatment.
Concurrent with the construction of a soil-bentonite wall, the
source material treatment component will be implemented. This
component entails excavation and destruction of specific areas
exhibiting concentrations of PCBs in excess of 500 ppm. The
estimated volume of PCB-contaminated source materials at
concentrations in excess of 500 ppm is 9000 cubic yards. This
volume of source material would be treated using one of the three
destruction technologies undergoing detailed evaluation, SC-2
On-site Thermal Destruction, SC-4 Dechlorination and SC-14 Off-
site Incineration. For the purposes of this analysis, the costs
are based on off-site incineration of 9000 cubic yards of source
material. Following completion of the excavation and treatment
of source material and construction of the soil-bentonite wall,
the site surface will be graded and capped with 18 inches of
gravel. .
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-37-
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The final component, in-situ soil flushing, provides for an
internal closed-loop recirculation system in the form of a soil
flushing process to extract the volatile organic and PCB
contamination from the existing soil matrix. The focus of the
treatment operation is to remove the VOCs and a percentage of the
PCBs from the soil matrix and thus eliminate the migration of
the residual PCB compounds. The recirculation proce~s flushes
the contamination from the soil column and then removes the PCBs
from the' flushing agent in an on-si te treatment process. Ground-
water from within the containment wall mixed with 1-2 percent
surfactant would serve as the flushing agent.
".
. .
.
Since a large portion of the site exhibits PCB contamination of
varying concentrations, and the majority of this contamination is
in the saturated zone, this alte~native was developed using
individual components ~hat could effectively control or treat the
various waste types. The encapsulation component provides for
the installation of a structure or hydraulic containment system
that surrounds the existing contaminated groundwater plume. The
removal of highly contaminated soils would ultimately reduce the
total volume of contamination and eliminate the higher concentration
PCBs that may not be effective1y treated by the in-situ soil
flushing process. The in-situ treatment process may not be
effective in reducing the concentration of PCBs in those soils
deep~in the saturated zone.
'.
"
The evaluation of alternative SC-7c indicates that this alternative
is not capable of assuring the long-term containment of the
hazardous wastes at the site and, therefore, will continue to
pose risks to human health and the environment. Also, the
questionable reliability of this alternative does not preclude
the need for future remedial action.
. .~~
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This alternative does, to a degree, reduce the volume, toxicity
or mobility of the hazardous wastes present at the site. The
sOil-bentonite wall is effective in reducing the mobility of
certain contaminants, but is less effective over extended periods
of time, in containing the highly mobile volatile organics.
Volatile organic compounds have already entered the overburden and
bedrock aquifer system and migrated beyond the site boun~ary.
Installation of a containment wall will not effectively inhibit
the continued migration of contaminants from the source to the
bedrock aquifer system, especially if bedrock is highly fractured.
In such cases, it is difficult to assume an adequate tie between
the slurry wall and the bedrock.
The treatment component of"this alternative will provide for the
permanent destruction of 9000 cubic yards of PCB-contaminated
soils. Detailed evaluations of the three destruction technologies
(i.e. SC-2 On-Site Thermal Destruction: SC-4 Dechlorination: SC-14
Off-site Incineration) are described elsewhere in this document.
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-38-
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Bench-scale studies were conducted to determine the effectiveness
of the flushing agent in removing volatile organics and PCBs from
the soil matrix. The results indicated that the flushing agent
was effective in removing the volatile organic contaminant fraction,
but, reduction of the concentration of PCBs was less significant.
Although the-effectiveness of the in-situ soil flushing process
is enhanced by the excavation and treatment of the highly contam-
inated source material, it is limited by many potential factors.
A major concern is channeling of the soil flushing agent during
'in-situ treatment, thereby preventing direct contact between
cleaning agent and contaminated soils. The bench-scale study
found that variable soil conditions at the site will result in
inconsistent flushing. Other limiting factors are listed in
Section 4 of the FS. Since the in-situ soil treatment component
is innovative, supplemental bench-scale and pilot-scale studies
would be required.
Overall, this alternative will reduce the total volume of PCB
contaminated soils by 9000 cubic yards. It appears that the
volume and mobility of the volatile organics will be reduced
over time, but PCB contaminated soils remaining on-site will
have to be managed appropriately. For this reason, it will be
necessary to implement a long-~erm monitoring and operation and
maintenance program.
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Thi~alternative poses some of the hazards associated with on-
site excavation of contaminated soils. Mitigative measures, such
as those discussed in the evaluation of alternative SC-2, will
be taken to control emmissions during excavation. The advantage,
though, is that a much l&~ser volume of contaminated soil would
be excavated than with other alternatives.
"
Placement of a gravel cap over the site and consolidation of all
waste material, including contaminated sediments, on-site does
reduce the risks posed to human health from direct contact with
soils as well as the risks posed to benthic organisms and higher
aquatic life. But, because this alternative may not be effective
in controlling the release of contaminants into the bedrock
aquifer, human and environmental receptors may continue to be at
risk in the future.
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Assuming a PCB clean-up leve~ of 500 ppm will be achieved through
evaluation, and a SO, removal of the residual PCBs remaining in
on-site soils, the estimated operation period is forty (40) years.
The engineering technology required to physically construct and
operate a closed loop recirculation system is available, but the
bench-scale study raised several unknowns relative to its effec-
tiveness in field- applications. The implementability and con-
structability of this alternative would have to be further defined
during a pilot study.
This alternative attains all Federal and State applicable or
relevant and appropriate public health and environmental require-
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-39-
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ments. Specifically, this alternative would be conducted in
accordance with RCRA 40 C.F.R. Part 264 Subpart G (Closure and
Post-Closure), Subpart N (Landfills) and Subpart F (Releases
from Solid Waste Management Units). If source material is treated
in an on-site or off-site incinerator, this alternative will
attain the approp~iate requirements under TSCA, which apply to
PCB incineration, and RCRA, which regulates incineration of
other organic compounds. All hazardous wastes transported off-site
would be in accordance with DOT regulations 49 C.F.R. 171-179
and 387. The capital cost for this alternative includes construc-
tion of a 'soil-bentonite slurry wall, an in-situ recirculation/
flushing system and off-site incineration of 9,000 cy PCB con-
taminated soils. The estimated capital cost for this alternative
is $33,882,000. The annual operation and maintenance (O&M) cost
for ~his alternative is $1,598,000. The estimated present worth
for treatment of 9,000 cubic yards of contaminated source material
in an off-$ite incinerator and operating an in-situ soil flushing
system for forty (40) years, assuming a 10 percent discount
rate, is $49,600,000.
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SC-14
Off-site Thermal Destruction
.'
The Off-site Thermal Destruction alternative entails excavation
of 64,000 cubic yards of PCB contaminated soils and sediments and
treatment in an off-site incineration facility.7 Soil character-
istics will be determined to en~ure appropriate methods of hand-
ling, transportation and disposal. All excavated material will
be containerized for shipment and all vehicles used for transpor-
tation will be carefully loaded, secured and decontaminated to
ensure that residual contamination is not transferred from the
site to public areas. The off-site facility must be capable of
accepting soil with high levels of vOlatiles, extractables,
including PCBs, and low to medium levels of metals.' Final resto-
ration will be achieved through backfilling the site with clean
fill, grading, loaming and seeding.
The evaluation of alternative SC-14 indicates that it will
permanently and significantly reduce the volume, toxicity and
mobility of the hazardous wastes at the site.
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In accordance with 40 CFR 5761.70 of TSCA, PCB incinerators are
required to have a destruction and removal efficiency (DRE) of
99.9999 percent. Incineration is a proven and reliable method of
treating PCB contaminated wastes. Residuals that will remain on-
site following treatment will be soils contaminated with PCBs at
a concentration below 10 ppm and sediments with PCB concentrations
less than 1 ppm (or the health-based cleanup standard selected for
the site). Minimal long-term management will be required fOllowing
the implementation of this alternative.
An air monitoring program will be implemented during the perfor-
mance of this alternative to reduce risks to on-site workers and
nearby residents. Mitigative measures such as those discussed in
the evaluation of alternative SC-2, will be taken during excavation
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-40-
to control emissions. Excavated soils waiting to be transported'
off-site will be contained and covered to reduce fugitive emission
of VOCs and contaminated particulate matter. The principal risks
to human health and the environment are associated with the trans-
portation of the contaminated soils to the off-site disposal
facility. Truck traffic to and from the site will increase dramat-
ically during the implementation of the alternative. It will take
approximately 4000 18 wheel trucks to transport 64,000 cubic yards
' of material to the off-site treatment facility and an equal
number of trucks to haul in backfill.
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Safety measures will need to be taken to prevent spills on highways
and contamination of the Fall River Reservoir, which is located
along the truck route.
It is estimated that the length of operation will be approximately
two (2) years. This period of performance is dependent on two
factors: the cleanup level selected for the site which directly
impacts the volume of contaminated soils that must be processedJ
and locating a hazardous waste management facility which will
accept the entire quantity of PCB-contaminated soil (64,000 cubic
yards). At present, there are only three facilities that will
accept PCB-contaminated soils ..~or incineration and these will
only accept small quantities at a time. Hence, large volumes
would require a phased delivery schedule.
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The off-site treatment alternative attains all Federal and State
applicable or relevant.and appropriate public health and environ-
mental requirements. Specifically, this alternative is in compliance
with 40 C.F.R. 5761 of TSCA, and RCRA 40 C.F.R. Part 264 Subpart G
(Closure and Post-Closure) and Subpart 0 (Incinerators). The
transport of contaminated soils off-site to the treatment facility
will comply with RCRA 40 C.F.R. Parts 262, 263, 264 and 265 and
DOT regulations 49 C.F.R. Parts 171-179 and 387. Further, in
acordance with CERCLA 121(d)(3), the selected off-site facility
must be in compliance with section 3004 and 3005 of the Solid
Waste Disposal Act (or, where applicable, in compliance with the
Toxic Substances Control Act or other applicable Federal laws)
and applicable State requirements.
The cost analysis represents costs for excavation, removal, and'
incineration of all contaminated material (64,000 c.y.). Unit
costs for incineration were based on estimates provided by 'waste
management facilities. The estimated capital cost for this alter-
native is $212,627,000. The annual operation and maintenance
(O'H) cost, which includes the monitoring program that will be
conducted throughout the entire operation period, is estimated
to be, $561,636. The estimated present worth for the treatment
of 64,000 cubic yards of PCB contaminated soils in an off-site
incinerator, assuming a 10 percent discount rate, is $213,595,000.
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A sensitivity analysis was conducted to determine how total
project costs change relative to different cleanup levels and
volume of treated soil. Costs were examined for six scenarios.
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-41-
The total volume of conta~inated material to be excavated, treated
and disposed of was 13,000 c.y., 22,000 c.y., 28,000 c.y., 48,000
c.y., 56,000 c.y. and 64,000 c.y. . The total project costs, presented
in Figure C-l7, are the present worth value of the capital costs
and operation and maintenance through the period of implementation.
MOH-l No Action
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This alternative is discussed earlier, combined with alternative
SC-l No Action.
HOH-2
On-site Treatment
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On-site treatment of groundwater entails extracting contaminated
groundwater from both the overburden and bedrock aquifers, treating
it on-site using clarification, filtration, air stripping and/or
carbon ads~rption (See HOH-2A and 2C for an evaluation of these
two technologies) and discharging it back to the groundwater. A
small portion of the effluent, approximately 5 to 10 gallons per
minute (gpm), will be discharged to the surface water to maintain
groundwater flow towards the contaminated zone. The discharge
to the surface water will receive advanced treatment to ensure~
protection of freshwater aquatic life and the environment. "
Figure C-l8 depicts a generalized flow chart for the treatment'
progJ!ss. ,
The projected remediation of .the groundwater involves installation
of extraction wells in both the overburden and bedrock aquifers
and the construction of recharge infiltration galleries. The
bedrock groundwater extraction wells will be installed at the
same time as the overburden wells. Short-term periods of pumping
(up to a week in duration) should be carried out for test purposes
upon installation of the system and at a second time prior to
initiation of full-time operation. In conjunction with the
extraction and recharge closed loop system, the groundwater
would be passed through an appropriate treatment system before
recharging into the aquifer. .
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In order to capture and extract the areal expense of the contami-
nant plume in the relatively shallow saturated overburden aquifer
without causing induced infiltration from the adjacent surface
water bOdies, a series of overburden wells, pumping at withdrawal
rates of no more than 5 gpm for each well, is projected. Initial
calculations indicate that eight (8) to twelve (12) extraction
wells will be required to provide effective contaminant capture.
The recharge of treated groundwater into the aquifer at specified
locations will flush and desorb contaminants from the pore water
contained within the soil matrix. Siting the recharge infiltration
galleries is critical relative to the influence of the recharge
mounding effects on the capture zones of the extraction well
field. A preliminary groundwater computer model using the USGS
HODFLOW program was 'used to assist 1n locating the possible
configurations of extraction and recharge wells that would provide
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-42- ,
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optimum extraction and flushing of the contaminated groundwater.
In order to capture the contaminant plume in the bedrock aquifer,
three (3) or four (4) extraction wells in the shallow bedrock
will be located along the' center line of the bedrock plume. Four.
additional wells will be located at the periphery of the high
contamination plume in the bedrock (See Figure C-13 TVO Concen-
trations: Bedrock Aquifer). Pumping rates will be 2 gpm or less
from each well or approximately one-third of the adopted extraction
rate for -the overburden extraction system.
Maximum groundwater extraction and recharge rates are limited by
the hydraulic conductivity of the aquifer material. Single well
pump tests over short time periods indicate a groundwater extraction
and recharge system at an approximate maximum pumping rate of 40
gpm is feasible. This pumping rate, combined with a 15-20 percent
discharge to the Copicut River and the remaining treated water
recharged to the aquifer, would allow for approximately 1.6 pore
water flushes per year. Prior to the design phase of this project,
a full-scale pumping and recharge test program will be necessary
to provide additional information on any potential modifications
to this concept.
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The groundwater at the site i~.contarninated with volatile organics,
heavy metals, PCBs and other extractable organics. The concentra-
tioQl anQ frequencies of contaminants detected in the groundwater
are presented on Table C-IO. Of the organic compounds present in
the groundwater, those which are semi-volatile and highly water
soluble such as acetone, methyl ethyl ketone and methyl isobutyl
ketone, are not effectively removed by conventional air stripping
or activated carbon processes. However, preheating the influent
in the air stripping process will enhance volatilization of these
compounds, thus increasing their overall removal.
"
There are two groundwater treatment alternatives, MOH-2A Heated
Air Stripping and MOM-2C Carbon Adsorption, which will undergo
detailed evaluation. Many of the unit processes such as metals
removal, neutralization and gravity sand filter, are the same
for each alternative. The primary difference between the two
alternatives is that MOM-2A focuses on the removal of ketones and
other volatile organics through the use of heated air stripp~ng
with no carbon adsorption whereas MOM-2C emphasizes the removal
of volatile 'organics but not. ketones, through the use of conven-
tional air stripping and carbon adsorption. Prior to implemen-
tation of either of the two on-site treatment alternatives, it
will be necessary to conduct treatability studies to determine
the effectiveness of each alternative on the site-specific waste
stream (i.e. contaminated groundwater). The design criteria for
these two alternatives are presented in Table C-ll. A detailed
discussion on the unit processes that are similar for each alter-
native is presented in Section 4 of the FS.
MOM-2A Heated Influent Air Stripping
,
Alternative MOM-2A utilizes heated influent air stripping to
remove volatile organics and ketones from the groundwater. The
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air stripping units would consist of packed towers filled with
plastic packing media such as pOlypropylene pall rings or telle-
vettese Air would be blown countercurrent to the liquid flow.
In this process, the influent water and the air are preheated to
about 1500 F. This 'temperature increases the'vapor pressure,
resulting in an increase in the removal of organics such as
ketones. One air stripper will have sufficient capacity to treat
the entire plant flow. The second unit will normally handle the
10 gpm stream for surface discharge. It will also serve as the
standby unit in case the first,needs repairs.
The emissions from the air strippers will be treated with a
catalytic burner. Heat will be removed to preheat the air stream
into the burner as well as the air stripper water and air influent
streams. Vapor phase activated carbon is not recommended for
controlling ketones since ketones break down easily in the presence
of carbon ~nd may ignite.
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The 10 gpm effluent will be polished to obtain very low levels of
metals and organics in order to protect freshwater aquatic life
in the Copicut River, particularly under low stream flow conditions.
The first stage in polishing will be a 0.2 micron rated microfilter
that will reduce the effluent metal concentration. An advanced~
metal removal reagent (i.e. insoluble starch xanthate or sodium
di-thiocarbonate) will be added prior to passing the effluent,
through the microfilter to aid in metals removal. The microfilter
effluent will be further treated with a carbon canister (2000 lb)
for removal of organics. 8
Figure C-19 shows the specific technologies and unit processes for
alternative MOM-2A. '
The evaluation of this alternative indicates that it will perma-
nently and significantly reduce the volume, toxicity and mobility
of the hazardous wastes present in groundwater. Air stripping is
a proven technology for removal of volatile organics and is one of
the most frequently used treatment technologies due to its relative
low cost and high efficiency. With an air flow to water ratio of
150 to 1 (volume basis), removal of volatile organics in the
. 95-99+ percent range is possible. Application of heat to the air
stripping process to remove ketones has also been proven in the
field and treatment of the off-gas using a catalytic burner is a
common practice in the organic ch~mical industry. Active restoration
of the aquifer will also reduce the mobility of volatile organics
in groundwater and surface water. Volatile organics increase the
solubility of other contaminants in groundwater, such as PCBs.
Removal of the volatiles and other organic compounds from the
groundwater will decrease the solubility and mobility of the PCBs.
At the completion of this remedial alternative, there may be
residual PCB contamination on-site but these compounds will be
relatively immobile.
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The reactor/clarifier process will produce a metal hydroxide sludg~
that will require proper disposal at a RCRA. approved hazardous
waste disposal facility. It is estimated that one drum of the
metal sludge per day, at approximately 45 percent solids, will be
produced and require disposal. .
During the performance of this alternative, a multi-media monitoring
program would be implemented to monitor the exposure to on-site
workers and nearby residents. Groundwater and surface water will
also be sampled on a ~egular basis to monitor the effectiveness
of the treatment system. A short-term benefit of this alternative
is that it will mitigate the off-site migration of contaminated
groundwater, thus reducing the risks posed to public health and
the environment. A long-term benefit is tha~ the groundwater will
be remediated to levels that are protective of human health and
the environment.
The implementation of this alternative requires assembling a
treatment system for a projected life of 25 years. The actual
operation period depends on the cleanup level selected by the
Agency. For the purposes of this analysis, it is assumed that
the project life for this alternative is ten (10) years based on
laboratory leaching studies anQ. the results of the fate and
transport mOdeling. .
The~OM-2A alternative will attain all Federal and State appli-
cable or relevant and appropriate public health and environmental
requirements. Specifically, this alternative complies with RCRA
40 C.F.R. Part 264 Subpart F (Groundwater Protection), the
Clean Water Act (PL92-500) - NPDES Permittlng and National Ambient
Air Quality Standards. If applicable, the disposal of metal
sludges off-site and/or spent carbon will be in accordance with
RCRA 40 C.F.R. Parts 262 and 263 and DOT regulations 49 C.F.R.
Parts 171-179 and 387.
The cost analysis was based on information from vendors and cost
estimating files. The estimated capital cost for this alternative
is $3,473,000. The annual operation and maintenance (O&M) is
estimated to be $565,000. The estimated present worth for ten
(10) years of operation, assuming a 10 percent discount rate, is
$6,945,000.
.
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MOM-2C Carbon Adsorption
Alternative MOM-2C utilizes air stripping and carbon adsorption
to remove volatiles and other organic compounds from the contami-
nated groundwater. A description of the air stripping process
was presented in the evaluation of alternative MOM-2A. Under
alternative MOM-2C, the air strippers, working under ambient
conditions, will only provide for the partial removal of ketones.
The emissions from the air strippers, therefore, will be treated
with vapor phase activated carbon since ketones will not be present
in significant quantities.
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Granular activated carbon would be used in the treatment process
to remove the organic compounds remaining after air stripping.
Ai~ stripping would be utilized to treat the bulk of contamination
o in groundwater to low levels. Carbon adsorption would be used
as a polishing step to further reduce the contaminants in groundwater
to the selected cleanup level. The activated carbon system consists
of two upflow fluidized bed type contactors arranged in parallel.
One bed will have sufficient capacity to treat the entire plant
flow. The contactors will contain 5000 pounds of carbon each
and provide an empty bed contact time of one hour, excluding the
bed expansion volume. The second carbon bed will normally be
used to treat only the 10 gpm waste stream for surface discharge.
If the first carbon bed needs servicing, the second will be a
standby unit.
The effluent polishing system was previously described in the
evaluation of alternative MOM-2A. Figure C-20 shows the specific
technologies and unit processes for alternative MOM-2C.
.'
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An evaluation of alternative MOM-2C indicates that this alternative
and alternative MOM-2A rate similarly against the evaluation criteria.
The evaluation of MOM-2C, therefore, will focus on the key differences
between the two on-site treat~ent alternatives in relation to the
evaluation criteria. Unless otherwise noted, the benefits and/or
limitations of MOM-2C will be the same as those described in the
evalUation of MOM-2A.
.'
Alternative MOM-2C will permanently and significantly reduce the
volume, toxicity and mobility of the hazardous wastes prrgent in
groundwater. This alternative, though, is not specifically designed
for the treatability of ketones. Ketones, although found at high
concentrations, are not widespread throughout the site. Treatability
studies and additional laboratory studies would have to be conducted
to determine if the concentration of ketones in the effluent pose
a risk to human health and the environment. Also studies will be
conducted to determine if ketone removal may take place due to
natural biodegradation when .the effluent is recharged into the
aquifer. The use of vapor phase activated carbon for adsorption
of organics in the air is a common practice in the electronics
and organic chemical industry and has been used at other CERCLA
sites. This unit process is expected to achieve a 90-95 percent
volatile organic removal in t~e air stripping tower exhaust.
In MOM-2C, activated carbon adsorption is added to the treatment
facility to achieve a higher effluent quality, thus resulting in
a shorter period of performance. Activated carbon beds will also
handle shock loads and adsorb higher molecular weight organics,
thus increasing this alternative's reliability. This unit process
is a proven technology with a long history of successful operation
in the municipal and industrial wastewater treatment fields.
Activated carbon is effective in removing organic compounds and
partially effective (40-70 percent removal efficiencies) in
removing inorganic compounds.
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The implementation of this alternative requires assembling a
treatment system for a project life of 25 years. The actual
operation period depends on the cleanup level salected by the
Agency. For the purpose of this evaluation, it is assumed that
the project lif~ for thi~ alternati~e will be ten (10) years.
The cost analysls for thlS alternatlve was based on information
from vendors and cost estimating files. The estimated capital
cost for alternative MOM 2C is $4,401,500. The annual operation
and maintenance (O&M) cost is estimated to be $693,000. The
estimated present worth for ten (10) years of operation, assuming
a 10 percent discount rate, is $8,659,292.
MOM-4 Pretreatment and Disposal at P~
Alternative MOM-4 entails extracting contaminated groundwater
from the overburden and bedrock aquifers, treating it on-site
with precipitation and air stripping and transporting it off-site
via a pipeline to a local POTW for final treatment. Coagulation
and precipitation are used to remove metals in a clarifier and
ambient air stripping will be used to reduce volatile organic
compounds. The treated effluent from the air stripping tower will
be sampled once a day to assure compliance with the treatment plant's
pretreatment standards. The effluent will be collected in a sump
and pumped to a POTW in the proximate area. Following treatment at
the POTW, the effluent is then returned to the site via a second
pipeline'for recharge into the groundwater aquifer. Figure C-21
presents an overall system flow diagram for alternative MOM-4.
The evaluation of this alternative indicates that it will perman-
ently and significantly reduce the volume, toxicity and mobility
of the hazardous wastes present in groundwater. The on-site unit
processes for this alternative, precipitation/coagulation and air
stripping, were previously discussed as part of the evaluation of
MOM-2A and MOH-2C. The proposed system, though, may not be HOM-2A
effective in reducing metals and organic compounds to levels that
attain the specific pretreatment requirements of the selected POTW.
If this is the case, activated carbon adsorption may have to be
added to meet the pretreatment requirements. Prior to implemen-
tation of this alternative, a treatability study would need to
be conducted to determine of this alternative can attain the
relevant pretreatment requirements.
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The ,short- and long-term pUblic health benefits and the magnitude
of risk reduction are similiar to that of the on-site treatment
alternatives, MOM-2A and MOM-2C. Also, the multi-media sampling
program described in the evaluation of MOM-2A is inherent to this
alternative.
"
The implementability of this alternative is dependent on the
acceptance and availability of a POTW. The contaminated ground-
water at the Re-Solve site contains a wide range of contaminants,
including PCBs. If the selected POTW is not permitted to treat
specific contaminants, then the permit would have to be revised.
In addition, the increased flow and/or waste stream may require
that the- POTW undergo structural mOdifications.
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The useful' life of the on-site treatment equipment is 25 years.
The actual operation period depends on the cleanup level selected
by the Agency. F~r the purposes of this evaluatio~, it is assumed
that the project life is ten (10) years.
Alternative MOM-4 attains all Federal and State applicable or
relevant and approriate public health and environmental require-
ments. Specifically, this alternative will be in compliance with
RCRA Parts 262, 263 and 264 Subpart F (Groundwater Protection),
C~ Sections 306 and 307 (Federal Pretreatment Requirements for
discharge to a POTW) and National Ambient Air Quality' Standards.
The estimated capital cost for this alternative is $2,890,000.
The annual operation and maintence (O'M) cost is estimated to be
$294,000. The est~mated present worth, assuming a 10 percent
discount rate, is $4,696,000.
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VI
Selection of Remedy
Description of the Selected Remedy
A.
The remedial action selected for implemen~ation at the Re-Solve
site is consistent with the Comprehensive Environmantal Response,
Compensation and Liability Act as amended by the Superfund Amendments
and Reauthorization Act of 1986 and, to the extent practicable,
t~e National Contingency Plan.
The selected remedial action is a comprehensive approach for
site remediation which includes both a source control and manage-
ment of migration component. Both components are necessary in
order to achieve the response objectives established for site
remediation and the governing legal requirements.
1.
Scope and Function of the Selected Remedy
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Source Control
The source control component entails excavation of 22,500 cubic
yards of PCB contaminated soils located in the unsaturated zone
and treatment in an on-site mopile dechlorination facility. Th.
estimated volume of contaminated soils is based on a clean-up
stangard pf 25 ppm PCB. In addition to on-site soils, this
component entails excavation of 3000 cubic yards of PCB contam-
inated sediments located in the wetlands north of the site and
the unnamed tributary and treatment on-site in the dechlorination
facility. The estimated volume of contaminated sediments is
based on d clean-up standard of 1 ppm PCB. The total volume,
therefore, of PCB contaminated soils and sediments undergoing
treatment on-site in the mobile dechlorination facility is 25,500
cubic yards. It is estimated that it will take two (2) years to
implement the source control component.
Implementation of this remedial action requires extensive on-
site handling and processing of contaminated soils throughout
the site. Figure C-22 illustrates the proposed site layout for
implementation of the source control component; An administra-
tion trailer, a laboratory trailer and storage and processing
facilities in addition to the dechlorination facility will be
located on-site. The space available at the site for the opera-
tions area and the support area is limited because the site is
surrounded by wetlands to the north and east, an Algonquin Gas
Pipeline right-of-way and various surface water bodies. It will
be necessary, therefore, to utilize the parcel of land adjacent
to the site along North Hixville Road in order to implement this
remedy.
The contaminated soils undergoing treatment are located in the
unsaturated zone. The unsaturated zone at the site is defined
as that area from the surface elevation to the seasonal low
groundwater table which, based on data gathered during the RI
and field observations made during the conduct of the RI and the
source control remedial action, is estimated to be elevation 85.
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However, the unsaturated zone and thus the seasonal low ground-
water elevation will be further defined during design of the
selected remedy.
Figure C-23 and C-24 present the areal and vertical extent of
PCB contamination greater than or equal to 25. ppm in unsaturated
zone soils, respectively. These Figures thus represent the
limits of excavation for the source control component.
The soils in the unsaturated zone, generally categorized as
fine sands and silts, are contaminated with both volatile
organics and PCBs. A concern of the residents in the area is
the off-site migration of airborne volatile organics and fugitive
dust contaminated with PCBs during conduct of the remedy. In an
effort to mitigate the off-site migration of contaminants, the
method of excavation wil~ be restricted to sheet piling vertical
cuts. The design of this method will reduce open air removal
of contaminated soils and thus, limit the potential for emissions~
Additionally, emissions suppression techniques such as foam and
water spray may be used to control odor and dust. .
The contaminated sediments are located in areas classified as
wetlands. Excavation in the wetland north of the site and the
unnamed tributary will result "In unavoidable impacts and disturb-
anc~ to wetland resource areas. Such impacts may include the
destruction of vegetation, the loss of indigenous species and the
migration of PCBs downstream. It is imperative, therefore, that
the impacts to the flora and fauna be minimized to the maximum
extent practicable, and that the disturbed areas be restored
to their original conditions.
!,
In an effort to mitigate impacts to the wetland areas, remed-
iation will be conducted during the seasonal low water periods
(typically late summer, early fall in Massachusetts). At other
periods of the year, the wetlands area north of the site discharges
to the unnamed tributary which, in turn, discharges to the Copicut
River. Both areas are also on occasion inundated by groundwater.
But during the seasonal low groundwater period, the ground water-
surface water interaction is sUbstantially reduced. The water
level in the wetland is not high enough to overcome natural
barriers and discharge to the unnamed tributary. The groundwater
table is also 80 low that grqundwater passes under the unnamed
tributary and discharges to the Copicut River. The unnamed
tributary i8 normally dry during this period. It is feasible,
therefore, to isolate the wetlands north of the site and limit
the resuspension and downstream transport of PCB contaminated
material while excavating PCB contaminated sediments. In addition,
PCB contaminated sediments can be exacavated from the unnamed
tributary with minimal impact on .the environment during this same
time period. During excavation of PCB contaminated sediments,
though, downstream monitoring of surface water will be conducted
to ensure that transport is not occurring.
Upon completion of the remedial activities in the wetla~d areas,
a wetland restoration program will be implemented. Altered
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wetland are~s will be restored to their prior condition. The
restoration program will be developed during design of ~he selected
remedy. This program will identify the factors which are key to
a successful restoration of the altered wetland. Factors may,
include, but not necessarily be limited tp, replacing and regrading
hydric soils" provisions for hydraulic control and provisions
for vegetative reestablishment, including transplanting, seeding
or some combination thereof.
The dechlorination process, discussed and evaluated as part of
alternative SC-4 in the Feasibility Study, is a soil treatment
process suitable for treating large volumes of soils contaminated
at low to moderate levels of chlorinated organics, such as PCBs.
The 25,500 cubic yards of contaminated soils and sediments will
be treated to a level of 25 ppm PCB. EPA recognizes that a
percentage of the 3000 c.y. of PCB contaminated sediment has a
concentration less than 25 ppm. However, contaminated sediments
at different PCB concentrations will be comingled during excavation'
and stockpiling, thus necessitating treatment of the entire
volume to 25 ppm PCB. This treatment level constitutes the
health based clean-up standard selected for PCB in unsaturated
zone soils. Each batch will be tested following treatment to
ensure attainment of the healt~ based clean-up standard prior to
being used to backfill the site. Following treatment of the
25,500 cubic yards of PCB contaminated soils and sediments and
placement 'back on-site, the site will be covered with 18 inches
of gravel. This does not constitute final site closure, but is
necessary for the implementation of the management of migration
component.
The on-site soils are also contaminated with other organic compounds
such as volatile organics. The areal extent of contamination is
similar for both PCBs and volatile organic compounds. Excavation
of the PCB source areas in the unsaturated zone, primarily in the
northwest quadrant near SB-25, will also significantly reduce the
mass of VOCs contributing to groundwater contamination. Bench-scale
studies on Re-Solve soils indicated that the dechlorination
process was effective in removing a percentage of the organic
compounds in soils, but complete destruction of such organic
compounds by dechlorination does not appear feasible. Therefore,
the residual organic compounds will undergo further treatment,
after being placed back on-site, as part of the management of
migration component. '
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Dechlorination is an innovative technology that has undergone
extensive testing on a laboratory scale level. The process has
also been the subject of extensive research at EPA's Hazardous
Waste Engineering Research Laboratory (H\JERL) in Cincinnati, Ohio.
HWERL, in coordination with EPA Region II, recently completed a
pilot scale study at the GE Moreau Superfund Site in South Glens
Falls, New York using a 40 gallon reactor. Preliminary results
indicate, that the process was successful in reducing PCB levels
in s'oi ls from approximately 7000 ppm to 10 ppm. HWERL and its
contractor, Galson Research Corporation, are planning to conduct
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additional pilot studies, using a 40 gallon reactor and a two
cubic yard reactor, in the future to further refine the process.
Prior to implementation of the full-scale process at the site,
it will be nece~sary to conduct a pilot study to ascertain the
implementabilityof dechlorination on a full-scale level.
In addition, the pilot study will yield information on the percent
reduction of other organic compounds in the Re-Solve soils, an~
volume and types of residuals and byproducts produced from the
reaction.
If dechlorination is determined not to be implementable at the
site, based on the results of the pilot study, on-site incineration
will be used as the source control treatment technology. On-site
mobile incineration was discussed and evaluated as part of alter-
~ative SC-2. Mobile incineration has been proven on both the
pilot- and -full-scale level and has been utilized at private and
Superfund sites to treat wastes similar to those found at Re-Solve.
Prior to full-scale implementation, a trial burn will be conducted
to demonstrate that the mobile incinerator can achieve a 99.9999
percent destruction and removal efficiency for PCBs. Residuals
and side streams will also be evaluated during the trial burn.
Treated soils will be placed back on-site and the site will be.
covered with 18 inches of gravel. All other component processes
of ~e squrce control component would remain the same.
Air monitoring will be conducted during excavation
Sampling stations will be located at the perimeter
and the air will be sampled for VOCs, PCB in vapor
metal and PCB particulates.
activities.
of the site
phase and
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Management of Migration
The management of migration component consists of a recirculation,
pump, treat and flush system. This component will be implemented
following completion of the source control remedial action.
- '
Contaminated groundwater will be extracted from both the overburden
and bedrock aquifers 'and treated on-site using alternative MOM-2c
Precipitation/Air Stripping/Activated Carbon/Filtration. The
treated groundwater will be discharged back into the aquifer via
a distribution system. The soils within these areas will be
flushed by this process, thus reducing the level of volatile
organic compounds.
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Groundwater will be treated to reduce contaminants to levels which
result in an excess cancer risk of 1 X 10-5. In this calculatio~,
it was assumed that the chemicals in the groundwater may interact
in an additive manner. The estimated period of time required to
achieve the remediation level is 10 years, during which time the
aquifer will be flushed an estimated 13-16 times (assuming 1. 6
flushes per year). Flushing of the aquifer will reduce the
level of residual organic compounds in the unsaturated zone to
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an estimated 1- ppm total volatile organics. However, completion
of the groundwater remediati9n component will be dependent on
the achievement of the target remediation levels for selected
indicato~ compounds in groundwater rather than soil cleanup'
levels for total volatile organics. EPA believes that, upon
achievement of the remediation level in groundwater, the soils
in both the saturated and unsaturated zone will be sufticiently
clean to be protective of human health and the environment.
This alternative was outlined in detail 'in the FS and summarized
in the Alternatives Evaluation section of this document (MOM-2C).
Prior to implementation of this remedy, it will be necessary to
conduct additional field studies which will include a full-scale
pump test/performance test and a pilot treatability study. The
purpose of the full-scale pump test is to determine the maximum
groundwater pumping and recharge rates, locations of extraction
wells and recharge trenches or wells. A treatability study will
be conducted to assess the effectiveness of alternative MOM-2C
in treating the contaminated groundwater at the site. Specifically,
the air stripping efficiency for semi-volatiles such as ketones
will be determined. Ketones, although not widespread on-site, are
found in high concentrations in areas. If it is determined that
ambient air stripping is not effective in reducing the concentration
of ketones to levels that are protective of human health, heated
air Stripping will be substituted for ambient air stripping.
The emissions from the heated air stripper would then be treated
with a catalytic burner instead of vapor phase carbon. The'
other component processes of alternative MOM-2C would still be
the same.
Performance monitoring will be implemented consistent with RCRA
S 264.l00(d), which requires the establishment of a monitoring
program to assess the effectiveness of the remedial alternative.
Residual water (effluent) contamination from the air stripping
process will be monitored during the groundwater treatment operation.
Groundwater and surface water will be monitored on a quarterly
basis during'implementation of the remedy at base flow which is
defined as a period following two days of no rain. Downgradient
monitoring wells and residential wells will be used to monitor
the groundwater qualitY1 surface waters in the vicinity of the
site will be sampled to monitor the levels and extent of contam-
ination. In addition, fish sampling will be conducted at stations
downstream of the site.
: .
Further, monitoring of wetlands will be conducted during active
restoration of the groundwater to ensure that extraction of
groundwater does not detrimentally impact the wetlands. If
negative impacts are observed, the rate of groundwater removal
will be decreased to the point that the wetland areas are not
adversely impacted.
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Upon completion of the groundwater remediation component, the
site will be graded and covered with one foot of loam and seeding.
In accordance with section 121(c) of CERCLA, the site shall be
evaluated every five (5) years to assure that the remedy is
protect;ive .and' that the hazardous waste remaining on-site do not
pose a threat to human health and the environment.
Cost Analysis
Detailed cost estimates were developed for both the source control
and management of migration components of the comprehensive remedial
action. Dechlorination and incineration costs were based on treat-
ment of 25,500 cubic yards of PCB contaminated soils and sediment.
The cost for alternative MOM-2C is based on 10 years of operation
and includes costs for additional field stu~ies such as a pump test
and treatability study. All costs were estimated with expected
accuracy of -30 to +50 percent in accordance with EPA Guidance
2!!. Feasibility Studies Under CERCLA. The' cost estimate for
dechlorination in~ludes an additional 10 percent contingency
because dechlorination is a new and innovative technology and,
as such, requires that a contingency be provided during scale-up
to accommodate variable sidestream process requirements.
The present worth for dechlorination is $9,231,000. The
capftal cost and operation and maintenance (O'M) costs are
presented in Tables C-12 and C-13, respectively.
If incineration is substituted for dechlorination, the present
worth for incineration would be $16,963,000. The capital cost
and operation and maintenance (O'M) costs are presented in
Tables C-14 and C-1S, respectively.
The present worth for alternative MOM-2C is $10,614,000. The
capital cost and operation and maintenance (O&M) costs are
presented in Tables C-16 and C-11, respectively.
The total present worth for the selected remedial action for
the Re-Solve, Inc. site is $19,911,000.
2.
Performance Goals
a.
Source Control
Soils
PCBs are the most significant component of the soil contamination
at the Re-Solve site.
A range of soil cleanup goals for the Re-Solve site was developed
based on the potential for PCB-contaminated soils to cause adverse
human health effects.9 The cleanup levels are ~eveloped for
several different exposure scenarios based on potential human
exposures to contaminated soils by direct contact. The estimated
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cleanup levels for each exposure scenario assumed surface exposure
to contaminated soil (i.e., not covered by clean soil). Individuals
who Come into contact with contaminated surface soils may be
exposed as a result of dermal contact, with subsequent absorption
of che~icals across the gastrointestinal tract lining.
The exposure scenarios addressed in this document are identical
to those evaluated in the Public Health Evaluation (PHE) for the
Re-Solve site. These exposure scenarios reflect both current
site use and hypothetical future site use, and each includes an
average and a plausible maximum exposure CAse. In this context,
-current use- refers to trespassing whereas -future use- refers
to redevelopment of the site for a hypothetical residence. At
present, site use consists 80lely of U8e by trespassers. Future
use might include residential use, 1nasMuch as there are residences
in the area and zoning is residential.
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The equation used to ca1culate
various exposure scenarios and
that presented in the Re-Solve
is rearranged to solve for the
soil cleanup concentrations for
levels of risk is identical to
site PHE except that the equation
soil concentration:
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This equation takes into account the amount of soil contacted and
ingested as a result of each visit to the site, the extent of PCB
absorption across the skin and the gastrointestinal tract lining,
and the frequency and duration of exposure (i.e., visits per year,
and total years site is visited). By substituting into the above
equation average case estimates for soil contact rate, skin
absorption factor, soil ingestion rate, ingestion absorption
factor, number of site visits per year, and number of years the
site is visited, a PCB soil cleanup level based on average exposure
conditions can be derived for a 8pecified level of cancer risk.
Similarly, by 8ubstituting in maximum exposure case estimates,
cleanup level. based on maximum exp08ure conditions can be derived.
In either ca8., the potency factor for PCBs, 4.34 (mg/kg/day)-l,
, is an upperbound estimate, and therefore even the average exposure
scenario r.sults in a conservative cleanup number.
In applying this approach to estimate health-based soil cleanup
levels"it 1s important to recognize the uncertainties inherent
in it. The three major sources of uncertainty are associated
with (1) the cancer potency factor for PCBs, (2) the value of
each exposure parameter, and (3) the overall set of exposure
assumptions used to derive a cleanup level. These uncertainties
are discussed in detail in Section 4 of the FS.
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Table C-18 presents the estimated soil PCB cleanup levels for a
range of lifetime cancer risks from 10-4 to 10-7 and a range of
exposure scenarios for the Re-Solve site. These cleanup levels
have been derived specifically fo~ the Re-Solve site and are
based on a particular set of exposure assumptions designed to
approximately reflect average and plausible maximum exposure
conditions for this site. In general, the assumptions that have
been applied in estimating cleanup levels are conservative.
The cancer potency factor for PCBs, in particular, is very
conservative, representing the 9S' upper bound cancer potency.
Many of the exposure assumptions are discussed in the Re-Solve
site PHE. As a result, the cleanup levels shown in Table C-l8
are unlikely to result in cancer risks higher than the indicated
level, but may result in risks which are considerably lower.
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The source control component of the selected remedial action'
entails excavation and treatment of soils contaminated with PCBs
at concentrations of 25 ppm or greater and located in the unsaturated
zone. All of the exposure scenarios are limited to potential
dermal exposure to the unsaturated zone soils. This cleanup
level corresponds to a '10-5 risk level for the average case
under future site use conditio~s. (The cleanup level presented
on Table C-18 is 30 ppm. As part of the discussion on the develop-
ment~f soil cleanup levels in the FS, EPA discussed some of the
uncertainty in the cancer potency factor and exposure parameters
used to estimate cleanup levels through the use of significant
figures. Because several of the soil contact rates and years
visited have only one significant figurec~the final cleanup
level can have one or, at most, two significant figures. By
convention,-the 30 ppm cleanup level is understood to be between
2S ppm and 35 ppm. Due to the uncertainty associated with the
approach used to estimate cleanuQ ,levels, EPA has selected 2S ppm
as being representative of a 10-5 risk level).
EPA is establishing its cleanup goal solely for PCBs in the
unsaturated zone (i.e. above the groundwater table) because it
is not reasonable to assume contact with soils below the groundwater
table would occur.
Sediments
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Three routes of exposure to PCBs in sediments were considered in
the development of the cleanup criteria for sediments near the
Re-Solve site. The first exposure pathway is the direct contact
between benthic org~nisms and PCBs in sediments. The second
pathway is the exposure of aquatic organisms in the water column
to PCBs emitted into the water from the sediments. The third
pathway is the exposure of predators, including terrestrial,
organisms, to PCBs that have bioacculumlated through food chains
to higher trophic levels.
The first pathway exposure of benthic organisms by direct contact
was addressed by reviewing the literature to identify sediment
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PCB concentrations that have been associated with adverse impacts
on benthic organisms. Although there are few data for freshwater
systems, some information is available addressing sediment toxicity
to saltwater benthic organisms. The sediment quality triad for
example, was used to derive a target PCB concentration in the
puget Sound based on sediment bioassays, sediment chemistry and
bottom fish histopathology.lO Using this method, the authors
concluded that minimal biological effects would be expected at
PCB sediment concentrations of 0.1 ppm with significant effects
expected at sediment concentrations greater than 0.8 ppm. The
apparent effects threshold (AET) approach identifies concentrations
of chemicals in sediments that are associated (at p - 0.05) with
biological effects including reduction of benthic community
diversity and toxic effects to amphipods in a bioassay. 11 PCB
sediment concentrations associated with effects using these
methods ranged from 0.13 to 2.5 ppm.
Based on the potential effects to benthic organisam, sediment
PCB concentrations in the range of 0.1 to 2.5 ppm were investigated
further. Water concentrations corresponding to this range of
sediment concentrations were estimated using a sediment model
based on work of Thibodaux12 and used by EPA to model
tetrachlorodibenzo-p-dioxin (r~DD) in sediment and water.13
The similarity in physicochemical properties between PCBs and
TCDD ..indicates that this approach should be valid. The model
assumes that volatilization is the primary fate process of PCBs
in water (i.e., photolysis, ~ydrolysis, and oxidation are negligible'
and included site-specific parameters for the fraction of organic
carbon in sediments, the depth of the water body, the average
wind speed and the width of the water body. It includes terms
for.mass transfer of PCBs from the sediment to the water, through
the water column, and form the water to the air and considers
PCBs partitioning from the organic matter to pore water. Assuming
sediment concentrations ranging from 0.1 to 2.5 ppm, concentrations
in the water of the wetland were estimated to range from 1.9 X 10-8
to 4.9 X 10-7 ppb. These concentrations are all below the
Ambient Water Quality Criteria (AWQC) for PCBs of 0.014 ppb.14
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Bioaccumulation through the food chain was assessed using the
WAST OX model. 15 Fish species collected near the site during
the RI included perch, brown bullhead, chain and redfin pickerel,
and American eel. The WASTOX.model has been used successfuly to
. predict PCB residues in Lake Michigan trout and kepone residues
in striped bass in the James River but has not, however, been
applied to most the species of concern at the Re-Solve site.
In addition; the model requires some very specific biological
information on species being modelled, including feeding habits
respiration rates and growth rates. Hence, the results of this
modelling effort were only used to provide a rough estimate of
potential residues in fish. Further, it is difficult. to know
what criteria residue value would be appropriate to compare
estimated residues to. The FDA tolerance limit of 2 ppm is not
based solely on health-based concerns. In order to estimate a
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health-based resIdue level, However consumption hab~ts and the
possible yteld of the water bodies must be known. In the absence
sIte-specIfic consumption data, estimated resIdue concentratIons
were compared to the FDA tolerance lim1t of 2 ppm.
ResIdues were estimated based on PCB sediment concentrations of
the wetland, of 0.1 to 2.5 ppm. For the purposes of .the model,
sediment concentrations in the Copicut were also considered in
this range. This latter assumption is supported by sed1ment
data gathered during the RI, where PCB concentrations ranged
from 0.2 to 2.7 ppm in the Copicut River and Carol's Brook.
Based on these assumptions, residues in the perch were estimated'
to range from ~.02 to 6.0 ppm1 bullhead from 0.01 to 2.3 ppm1
and American eel from 0.05 to 13.0 ppm. These results of the
model indicate that at the upper end of the invest1gated range,
PCB residues 1n fish may exceed the FDA tolerance limit. It
should be noted that of these four organisms, only the American
eel would be expected to enter the wetland, and the chances of
thi~ o~curing-are not known. Other fish species can be exposed
to res1dues in sediments of the wetland and unnamed tributatary
by water transport, sediment transport and also possibly by the
movement of food organisms into the river.
In selecting the PCB sediment cleanup level for the site, EPA
cons1dered the following factcfrs: The range of PCB sediment'
concentrat1ons (0.13 ppm to 2.5 ppm) associated with adverse
impitts to benthic organisms1 location and concentration of PCB
contamination, and: adverse environmental impacts. Based on an
evaluation of these factors, EPA is select1ng a cleanup level of
1 ppm for PCB contaminated sedIments located 1n the wetlands
north of the site and the unnamed tributary. These contam1nants
will be excavated and treated in the on-site dechlorination
facility.
b.
Management of Migration
Target concentrations for groundwater remediation were developed
1n a manner consistent with EPA's Superfund Pub11C Health Evaluatlon
Manual (OERR 1986). The first step in the process was to reV1ew
and mod1fy the list of indicator chemicals selected for assessing
baseline risk (Public Health Evaluation, Re-Solve Supplemental RI,l987)
based on chemical class and treatability. Secondly, the lIst of
chemicals found in 'groundwater were review~d, also taking into
account chemical class and tteatability, to determine if additional
chemicals should be considered in the design of the alternative.
The indicator chemicals identified as part of the baseline
risk assessment were:
Lead
Polychlorinated Biphenyls (PCBs)
Tetrachloroethylene
Trichloroethylene
Trans-l,2-D1chloroethylene
Vinyl Chloride
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ThlS list of indicator compounds can be organized 1nto chemical
class. Th1S list is compr1sed of an inorgan1C compound (lead),
a chlorinated organic compound (PCBs) and volatile organic compound~
(tetrachloroethylene, trichloroethylene, trans-l,2-d1chloroethylene
and vinyl chloride). Further, ind1vidual chemicals 1n each
chemical class can be classif1ed as carcinogens and non-carc1nog~ns.
Based on a review of the list of all chemicals found in ground-
water at the site, additional chem1cals were identified for
inclusion as indicator chemicals. These chemicals and their
respective chemical class are7 acetone, methyl ethyl ketone and
methyl isobutyl ketone (ketones) and methylene chlor1de (volatile
organic compound).
Target concentrations were developed for each class- of compounds.
,Within each class, some chemicals may be more difficult to treat
than others. or may pose a greater risk to public health. These
more persistent or greater r1sk chemicals were cons1dered in
the des1gn of the alternative.
Ketone Ind1cators
Ketones are semivolatile compq~nds which are not effectively
treated by aeration or granular activated carbon. A pilot study
w1ll be conducted to determine if heated air stripping should be
utilized 'to reduce the concentration of ketones in groundwater
to levels that are protective of human health. A flnal determlnation
wlll be made dur1ng deslgn of the alternatlve.
Inorganic Indlwators
Lead 1S a non-carcinogenic inorgan1c compound with a maximum
contaminant level (MCL) of 50 ppb. (MCLs are standards developed
under the Safe Drinking Water Act (SDWA) for publlC water suppl1es.
These standards are based on health, technological and econom1C
feasibil1ty). This MCL, though, is currently undergoing rev1sion.
The new proposed MCLG for lead is 20 ppb. EPA .is selecting 50 ppb
as the target remed1ation level for lead 1n groundwater. But,
if the proposed MCLG undergoing review and comment is adopted as
elther a proposed or final MCL prior to the initiation of the
groundwater treatment component, the cleanup standard for lead
will be the more stringent 8tandar~.
VOC Indicators
The majority of the indicator chemicals are volatile organic
compounds. Trichloroethylene, tetrachloroethylene, vinyl chlorlde
and methylene chlor1de are known as suspected human carcinogens
whereas trans-l,2-dichloroethylene is a non-carc1nogen. The
chemicals with1n this class that are the more persistent and
which pose the greatest threat to public health w111 be used 1n
the des1gn of the alternat1ve.
Based on th1S criter1a, EPA concludes that trichloroethylene
(TCE), tetrachloroethylene (PCE) and methylene chlor1de are the
appropr1ate VOC indicator chem1cals for the Re-Solve slte.
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EPA believes that a target level for groundwater remediat10n for
volatile organics of 5 ppb each for TCE, PCE and ,methylene chlor1de
will provide adequate protection of public health and the env~ron-
'mente The f1nal MCL for TCE 1S 5 ppb. The proposed MCL for PCE
is st1ll under development, but it is reasonable to assume that
the same regulatory approach can be taken for PCE as TCE since
these two compounds have the following similarities: weights of
evidence for carcinogen1city, practical quantlficatl0n leve11
and treatment efficiency. The concentration of methylene chlor1de
corresponding to a 10-6 risk level is 5 ppb.
The incremental lifetime cancer risk associated with ingestion.
of TCE, PCE and methylene chloride at 5 ppb each in groundwater
is approximately 1 X 10-5, assuming additivity. The indlvidual
and total risk level associated with a 5 ppb concentration for
each of the-contaminants is presented in the following table:
R1Sk Associated With
A 5 ppb Concentratlon
Cor.tpound
Trichloroethylene
Tetrachloroethylene
7 X 10-6
2 .X 10-6
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~ethylene Chlor1de
1 X 10-6
10 X 10-6
Total
. 1 X 10-5
Since TCE, PCE and methylene chloride were not present at the
same concentrat10ns in groundwater, they may not appear at the
same relative concentrations after groundwater treatment. Risks
from exposure to groundwater from these three chemicals will
depend on the1r relative ratio. EPA believes that a target
concentrat1on of 5 ppb for each chem1cal is sufficiently protective.
Vlnyl Chlor1de is a potent carcinogen with a final MCL of 2 ppb.
It was not included in the calculation of the overall risk assoc1ated
with the groundwater following remediation because the treatment
process will reduce the concentration of vinyl chloride to a
level well below the MCL. The effectiveness of aeration in
treat1ng a chemical can be measured by the compound's Henry's
Law Constant. Generally, the removal of a contaminant by aeration
increases with the Henry's Law Constant. The Henry's Law Constant
for vinyl chloride is 359,000, which, relatlve to other volatile
organic compounds, is extremely high. This, coupled with an
adequate alr to water ratio (150:1) in the aeration process
should result in near total removal of vinyl chlor1de dur1ng
trea tme nt.
Trans-l,2-d1chloroethylene was another volatile organ1c not
lnvolved 1n the calculation. This compound is a non-carc1nogen
w1th a proposed MCLG of 70 ppb. The aeration process will also
suffic1ently reduce the levels detected 1n groundwater to belQw
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the proposed MCLG. Treatment to 5 ppb for TCE, PCE and methylene
chloride is expected to reduce other compoun9s identif1ed 1n
groundwater to non-detectable levels. However, 1n the event
that other compounds are at detectable levels upon meeting the
TCE, PCE and methylene chloride target cleanup levels for ground-
water, it will be necessary to determine the overall risk associated
with all compounds detected. A determination will be made by
EPA upon achieving 5 ppb for TCE, PCE and methylene chloride in
groundwater as to whether the aquifer cleanup has sat1sf1ed
remedial objectives and to assure that water quality is adequately
protective of human health and the environment.
PCB Indicator
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Both PCBs and VOCs are found at high concentrations in the saturated
zone at the site. Each class of chemicals has distinct character-
istics. VOCs are highly soluble in groundwater, whereas PCBs
are inherently 1nsoluble and have a tendency to adsorb onto sOlIs
The solubility of PCBs, though, 1S enhanced in the presence of
VOCs and appears to increase as the concentration of VOCs increase.
High concentrations of VOCs at the site cause PCBs to desorb
from saturated soils and d1ssolve in groundwater. This is supported
by the fact that PCBs were de~ected in filtered groundwater
samples at levels h1gher than"'the normal 15 ppb maximum sOlub1lity.
As ~pected, VOCs were also detected at high concentrations 1n
the same sa~ples.
Once in solution', PCBs m1grate in groundwater, but at a slower
rate than VOCs. The migration rate of PCBs is determ1ned by the
VOC concentrations in the sOlI matrix. High VOC concentratlons,
such as those presently found at the site, will cause PCBs to
migrate an estimated 10 feet in 15 years. On the other hand, 1f
VOC concentrations are reduced to the target remed1ation levels
selected for groundwater, PCB m1grat10n will decrease to about
10 feet in 1200 years.
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The selected remedial action entalls treatment of PCB contaminated
soils in the unsaturated zone and active restorat10n of the ground-
water to a 1 X 10-5 risk level. Significant concentrat10ns of PCBs
will remain on-site in the saturated zone, but VOCs, other organic
compounds and metals will be reduced to the target remediation
levels for groundwater treatment. The reduction of contaminant
levels, specifically VOCs, will reduce the solubil1ty and mob1lity
of PCBs in groundwater.
However, PCBs will still be present at low concentrations in on-
site groundwater. Assuming even distribution of the PCB mass in
the waste management area, which is defined as the area within
the eX1sting fence line, the estimated solubility of PCBs in the
interstitial pore water is 10 to 15 ppb. This concentration is
far 1n excess of 0.08 ppb, the health based cleanup level for a
10-5 cancer risk for PCBs. Th1S contamination will be lim1ted
to the waste management area only. Eventhough PCBs may desorb
from saturated zone sOlIs and solubil1ze 1n groundwater, PCBs
have a chemical tendency to adsorb onto the next available and
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less contaminated soil particle because the sOlI-water partitionlng
coefficient for PCBs favors soils. In addltion, the time perlod
that PCBs are in solution is very low, thereby inhlbiting migratlon.
As mentioned previ~usly, the expected migration of PCBs in ground-
water at detectabl.e levels would be 10 feet ln 1200 years, assumlng
that volatile organic compounds in groundwater are remedlated
to target cleanup levels. Therefore, while low level PCB contamln-
ation may be present in groundwater on-site following groundwater
remediation, for all pract~cal purposes they will not migrate.
In order to attain a PCB level of 0.08 ppb, the health based
cleanup level, in groundwater everywhere on-site, PCBs in the
saturated zone would have to be reduced to a concentration of
0.15 ppm. This would require the excavation and treatment of an
additional 70,000 cubic yards of PCB contaminated soils in the
saturated z9ne. Because excavation in the saturated zone is
exceedlngly difficult technically, and is quite costly, the
Agency has reviewed the question of whether such excavatlon is
necessary for a protectlve remedy.
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The public health evaluation indicated that remediation of the
PCBs ln the saturated zone is not necessary to protect against
dermal exposure and the only ~ema1ning potential exposure pathway
to PCBs is ingestion of groundwater.
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Due to the ubiquitous nature of the PCBs at the site and the
presence of PCB contamination in the saturated zone, EPA believes
it is technically infeasible to attain this level of cleanup
with any confidence that the water quality on-site would attain,
or remaln at, ac~eptable levels over time. The PCBs 1n the
saturated zone will not migrate off-site because of their low
mobllity 1n groundwater. Thus, the PCBs in the saturated zone
will remaln on-slte.
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Further, work in the saturated zone is complicated by the constant
presence of water, which makes it exceed1ngly dlfficult to remove
all of the PCB contaminated soil. As a result, the Agency cannot
assure that excavation of the unsaturated zone would actually
result in the attainment of the spec1fled cleanup levels for
PCBs in on-s1te groundwater.
Upon completion of the selected remedial action, PCBs will be
present in groundwater on-site in excess of the health based clean-
up level for a 10-5 cancer risk. However, these levels will
only be found within the waste management area, which should not
restri'ct the placement of a drinking water well immediately
outside the boundary of the waste management area.
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The target remediation level fQr TCE, PCE and methylene chloride
will be achieved at all points on the waste management boundary.
This compliance point varies between 200 and 250 feet from the
center of the plume, (i.e. point of exposure) Wh1Ch is located
in the center of the waste management area. The f1nal locatlon
of the compliance pOlnt will be determined during deslgn of the
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remedial action. For the purposes of this analysis, EPA is
assuming that the compliance point is located 200 feet downgradient
from the ~enter of mass of the plume.
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EPA developed a fate and tran'sport model to simulate the ground-
water extraction at the Re-Solve site. This is an iterative
technique where for' each day, the model calculates the mass and
concentration of contaminants remaining in groundwater as a
function of the mass of contaminants removed from groundwater
due to pumping, and the mass of contaminants entering the ground-
water due to leaching from the source soils. The leaching rate
constant was derived experimentally.
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The model was run in a scenario where the unsaturated zone soils
(22,500 cubic yards) were excavated and treated on-site in the
mobile dechlorination facility and subsequently placed back on-
site. It was assumed that treatment would result in an 80 to 90
percent reduction of the mass of VOCs in the unsaturated zone.
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A sensitivity analysis was also done on the leaching rate constant
(determined by data from the lab columm study conducted as part
of the FS) to determine how the model is affected by this,parameter.
Results indicated that this model was very sensitive to this
paranreter' and a change in this leaching rate constant by as little
as a factor of two or three can dramaticall'y change the predicted
time of cleanup.
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T~e fate and transport model was modified to calculate cleanup
time with and without the hydrolysis mechanism, using the hydrolysis
half-life of tetrachloroethylene (PCE) as the decay rate. Due
to the nature of the model, this additional mechanism did not.
greatly decrease the cleanup times, although it did reduce them.
This probably Occurs because the leaching from soil into the
water is the ,rate limiting step, and therefore the hydrolysis of
the contaminants in the water does not drastically reduce the
time to cleanup the site.
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A second model which was developed for the site, a groundwater
flow model, and was used to estimate the number of aquifer volumes
necessary to flush contaminants and the associated treatment
time in order to achieve the target remediation level for PCE in
a Source well placed on-site in the center of the plume. PCE
was selected as the indicator compound for this analysis because
its lower vapor pressure and solubility compared to other indicator
compounds is such that its natural transport away from source
areas is slower than other volatile organics. Further, PCE
comprises 12.34 percent of the mass of total volatile organics
(TVO) in the saturated zone.
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A third model, the Soil Contaminant Evaluation Methodology (SOCEM),
was used to determine the relationship between residual levels of
contaminants in the source area and the resultant concentrations
further downgradient. The SOCEM model was used to determine the
allowable concentration of PCE and TVO in a source well located
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in the center of-the plume, given that the target remediation
level for PCE at the point of compliance is 5 ppb. The number
of contaminated aquifer volumes and extraction/treatment time
were adjusted to reflect the distance from the source well to
the point of compliance.
Based on the results of these modeling efforts, an estimated 16
aquifer volumes will have to be pumped and treated over a period'
of 10 years to attain the target remediation levels at the
point of compliance (i.e. 5 ppb each for TCE, PCE and methylene
chloride). ,These estimates'are based on a pumping rate of 40
gallons per minute which would allow for approximately '1.6 flushes
per year. The resulting concentration for PCE and TVOs in a
source well located in the center of the plume on-site would be
an estimat~d 24 ppb and 200 ppb, respectively.
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Presently, the highest concentration of TVOs in groundwater on-
site 1s 200 ppm. Treatment of groundwater 'to 200 ppb on-site
represents a 99 percent reduction in the concentration of TVOs.
During remediation of groundwater at the site, the unsaturated
zone soils will be flooded and both unsaturated and saturated zone
soils will be flushed approximately 16 times over 10 years.
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EPA estimates that the concentration of TVOs in soi15 on-site
will be reduced to 1 ppm. This concentration will not however,
be used as a basis for achievement of the groundwater remediation
goals. Groundwater remediation will be determined based on '
attainment of the target cleanup levels for the selected indicator
compounds at the point of compliance, the waste management boundary.
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B.
Statutory Determinations
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CERCLA as amended by SARA requires the Agency to select remedial
actions, to be carried out under section 104 of CERCLA or secured
under section 106 of CERCLA, which are in accordance with section
121 of CERCLA and, to the extent practicable, the NCP. Accordingly,
the selected remedy presented herein is consistent with CERCLA
including the cleanup standards in section 121, and to the extent
practicable, the NCP.
Under its legal authorities, EPA's primary responsibility at
CERCLA sites Is to undertake remedial actions that are protec-
tive of human health and the environment. In addition, section
121 of CERCLA provides a number of factors and procedures for
the Agency to consider and follow in selecting remedies.
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First, section l2l(b) creates a strong statutory preference for
remedial actions that utilize treatment which permanently and
significantly reduces the volume, toxicity or mObility of the
hazardous substances, pollutants or contaminants as a principal
element. The statute prescribes that, in choosing a final remedy,
the Agency must select a remedial action that is cost effective
and uses permanent solutions and alternative treatment technologies
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or resource recovery technologies. In addltion, EPA may select
an alternatlve remedial action meetlng the objectives of sectlon
121 whether or not such action has been achieved in practice at
any other facility' or slte that has simllar characterlstics.
Further, section 121(d) provides that EPA's remedial actlon,
when complete, must comply wlth applicable or relevant and
appropriate environmental standards established under Federal
and State environmental laws.
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Source Control
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EPA has determined that the 25 ppm cleanup level for PCBs in
soils is protective of human health and the env1ronment based
upon a number of reasonable and valid (albeit conservative)
assumptions. F1rst, the Agency has assumed that the site has
cons1derable potential for future res1dential development.
Should such development occur, in the absence of remediation, an
individual might well be exposed to contaminated sOlls in the
unsaturated zone.
The site is presently zoned for single family residential and
agr~ultural use. Currently the area surround1ng the slte is
undergo1ng extenslve residential development. New housing develop-
ments have gone in along Hixville Road, Old Fall R1ver Road and
Reed Road. Indeed one adjacent property owner has requested a
permit to build a resldence on the property. Thus, the )rea 1S
under development pressure and EPA has reasonably assumed 1n lts
exposure analysls that indlviduals would seek to develop the
Re-solve site and the lmmedlately surroundlng property.
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Note that the slte might be used even if drinking water wells
cannot be drilled on the property. The owners of the Dartmouth
Landing Trust, a suLdivlslon presently under constructlon and
located one and one-half miles south of the site, between Hlxvllle
Road and Reed Road, plan to extend a waterline to provlde publ1C
water. Such a waterline might be proposed for the Re-Solve site.
Further, the land might be used for recreational purposes or for
agricultural purposes without the necessity of a drinking water
well on the property.
The 25 ppm cleanup level is associated with an excess cancer
risk of no greater than 10-5. It is likely that the true risk
is considerably lower, as conservative exposure assumptions were
used in the calculation. Also, as part of final site closure,
the site will be covered with one foot of loam and seeding.
This final cover, although not permanent, will further inh1b1t
the threat posed from d1rect contact with soils, thereby further
lower the risk.
EPAalso believes that the I ppm PCB cleanup level for sedlments
located 1n the wetland north of the site and the unnamed tr1butary
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is protective of human health and the enVlronment (i.e. benthlc
organisms, aquatic organisms and organisms at higher trophic
levels). The selection of this cleanup level was a risk management
decision in which the followlng informatlon was considered: the'
protectiveness of a 1 ppm PCB cleanup level for the three pathways
of ~xposure discussed previouslYJ the overall protectlveness,
and: adverse environmental impacts. The protectiveness of the 1 ppm
PCB cleanup level on each pathway of exposure is:
BenthlC Organisms
As dlscussed previously concentrations below 1 ppm have been
associated with adverse effects in benthic organisms in saltwater
systems. Although similar studles have not been conducted in
freshwater systems, there is no information to suggest that
freshwater organisms are less sensitive to PCBs than saltwater
organlsms. 'Of the freshwater organlsms that have been tested
,uslng PCBs in water, amphipods (Gammarus pseudolimnaeus) and
m1dges (Tanytarsus dissimilis) appear to be part1cularly senslt1ve
to PCDs. For example, the 7-day LCSO for G. pseudol1mnaeus
was 5 ppb, and for pupae of T. dissimilis, a 3 week LCSO of
0.45 ppb has been reported. These organ1sms or closely related,
organisms would be expected to:,occur near the Re-solve site.
Assuming that freshwater benthic organisms are at least as sensitive
to ~Bs as saltwater benthic organisms, a sedlment PCB concentrat10n
of 1 ppm would be protective of some but not all adverse effects
of the che~lcal on benthic organisms.
Aquatic Organlsms
The AWOC for PCBs of 0.014 ppb is based on this predat10n of
flSh by mink, and not on the toxicity of PCBs to aquatlc organlsms.
Eleven llfe-cycle or partial llfe-cycle tests are available for
3 invertebrate and 2 freshwater fish species1 chronic values
ranged from 0.2 to 15 ppb. Hence, the AWOC of 0'.014 ppb 1S
protectlve of the aquatic species tested and a1so may be protect1ve
of predators. Assumlng a sedlment concentration of 1 ppm, the
water column of the wetland was estimated to contaln 1.9 X 10-7 ppb,
which is below the AWOC of 0.014 ppb.
Higher Trophic Levels
As discussed previously, the biomagnification of PCB residues
through the food chain was evaluated by uSlng the WAST OX model.
Assumlng a sediment concentration of 1 ppm res1dues 1n fish were
estimated to range from 0.2 to 5.0 ppm and hence may exceed the
FDA tolerance limit. As previously noted, the chances of fish
entering the wetland are probably low, but fish in other water
bodies near the wetland may be exposed to PCBs from the wetland
through transport by water, sediment and prey organlsms. It
should also be noted that American eels and amphibians such as
frogs appear to be particularly efficlent ammulators of PCBs.
The food chaln model used.may underestimate PCB residues ln
these specles.
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-66-
"
EPA recognizes that the 1 ppm PCB cleanup level may not offer
full protection for all pathways of exposure. However, EPA's
final decision was not based solely on protectiveness, but also
involved the consideration of the adverse environmental impacts
posed by various levels of remediation and the locat10n of such
remed1al activities.
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First, cleaning up PCB contaminated sediments to a more protective
level (i.e. 100 ppb) would most likely result in no adverse
effects on benthic organisms and the resultant residues in fish
would probably not exceed the FDA tolerance limit, but, 1n order
to achieve this level of protection, it would be necessary to
disturb significant wetland resource areas, almost twice the area
that will be disturbed to achieve the 1 ppm cleanup level. EPA I
does not believe that a lower cleanup level is warranted consider1ng
the increas~d disturbance of wetland resource areas and subsequent
loss of flora and fauna.
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EPA also cons1dered cleaning sed1ments to a less protect1ve level
(i.e. 2.5 ppm), but rejected th1S cleanup level because it would
not be protective of any of the three pathways of exposure.
F1nally, PCBs were detected at levels greater than 1 ppm in the
Copicut River and Cornell Pond" but EPA has chosen not to remed1ate
these areas because of 'the potent1al adverse environmental impacts.
The ~etla'nd and the unnamed tributary can be isolated from the
Copicut River dur1ng the seasonal low groundwater period. Mitigative
measures can be implemented during excavati9n of these sed1ments
to min1m~ze downstream migration of PCBs. Remed1ation (l.e.
excavation) in the Copicut River and Cornell Pond, however, wiil
most likely result in the increased bioavailability of PCBsl7
and downstream migration of PCBs adsorbed to sediments.
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Instead of excavating PCB contaminated sediment at levels greater
than 1 ppm in the Copicut River and Cornell Pond, and thereby
potentially magn1fying the problem, EPA will mon1tor the fish in
the area. '
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Management of M1gration
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The Agency's decision to restore the groundwater at the Re-SQlve
site boundaries to a cancer risk level of 1 X 10-5 was based
on several factors. First, EPA considered the Agency's Groundwater
Protection ~ (GWPS) (Office of Groundwater Protection
August, 1984). Tne GWPS provides gUidance concerning how different
groundwaters throughout the country should be classified and to
what extent cleaning up a particular groundwater is appropriate,
given where it fits into the classification scheme. EPA also
considered the Agency's draft Guidance on Remedial Actions for
Contaminated Groundwater !l Superfund Site~ober, 1986T7
This guidance directs the Agency to conS1der a 10-4 - 10-7
range of risk levels in selecting the appropriate risk level for
the groundwater at the site.
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The policy under the GWPS establishes groundwater protection
goals based on ~the hIghest benefIcial uses to whIch ~round-
water havIng signifIcant water resources value can presently or
potentially be put." GuidelInes for protection of aqulfer$ are
dIfferentIally based, relatIve to characterIstics of vulnerabIlIty,
use and value. Under the classification scheme, the groundwater
at the Re-Solve site is Class II groundwater. ThIs groundwater
is considered to be a current drinking water source since ground-
water is used for drinking water within a two mile radius (i.e.
classification review area). '
..
EPA believes that active restoration of the groundwater is appro-
priate for the site. Presently, the residents in the area obtaIn
their groundwater from both the overburden and bedrock aquifer
systems. Contamination in the bedrock aquifer has migrated
beyond the Copicut River and Carol's Brook and could potentially
impact the quality of drinking water in the resIdential wells
located in the vicinity of the site. As noted above, the owner
of the property adjacent to the site along North Hixville Road
has commenced proceedIngs (i.e. to obtain local permIts) necessary
for the placement of a home on the property. This property in
question was the location of a former residence which obtained
drinking water from a shallow on-sIte overburden well.
Finally, it is reasonable to issume that a residence could be
placed on, or near the site followIng remediation. As mentioned
prevIously, source soils wIll be remedlated to levels that are
protective of human health and the environment. Under these
CIrcumstances, groundwater obtained from every pOInt outside the
waste management area could be used for drinking water purposes.
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Consistent with the draft Guidance on Remedial Actions for
Contaminated Groundwater at superfund SItes and EPA's SuPerfund
Public Health EvaluatIon Manual, EPA evaluated a risk range of
10-4 to 10-/ IndivIdual lIfetIme cancer rIsks for carcInogens
in selecting a risk level for groundwater. In selecting the
appropriate risk level for the site and the rate of restoratIon,
EPA considered the following major factors:
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Site and groundwater characteristics7
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Cost, reliability, speed and technical
feasibility of groundwater response actions7
Anticipated future need for the groundwater7
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PotentIal for spreading of the contamInant plume; and
EffectIveness and reliability of institutIonal controls.
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EPA selected a 1 x 10-5 risk level for all groundwater outSIde
the waste management area because thIs groundwater is presently
used for drinkIng water purposes. EPA applIed drInkIng water
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-68-
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standards (MCts) ln establishlng ~he appropriate cleanup level for
the site. EPA believes that MCts are protectlve of human health.16
As the legally enforceable standards under the Safe Drinklng
Water Act, MCts determlne the level of water quallty that lS
acceptable for consumptlon by people who obtain their drlnklng
water from public water supplies. MCts or an equivalent level
of. protection (as discussed earlier, this level of protection
corresponds to a 10-5 cancer risk) were' used to calculate the
level of residual risk posed by consumption of groundwater followlng
completion of the remeaial action. EPA conslders a 1 x 10-5
risk level to be adequately protective 9f human health.
For several ~easons, EPA rejects a level of 10-4. First, this
is a Class II aquifer which is presently being used as a drinking
water Source. EPA anticipates that the area surrounding the
site wlll centlnue to be developed for residential use, thus
increaslng the future need of this aquifer. Given the hydrogeologic
uncerta1nt1es at the slte, and the lack of an alternatlve water
supply system 1n the area, EPA does not belleve a 10-4 level
would leave an adequate margln for error as groundwater use
expands.
..
Secondly, sectlon 121 of CERC~. requires that Superfund response
actlons must attain applicable 'or relevant and approprlate require-
ments. MCts under the Safe Drlnking Water Act are ARAR's for
site remedlatlon. If groundwater is remediated to a 10-4 rlsk
level, the res1dual concentratlons of individual contaminants at
the point of compliance would be ln excess of their MCts.
EPA also rejects 10-6 and 10-7 risk levels. First, the
population 1n the area has not histor1cally been exposed to
potentially hazardous levels of contamlnants for an extended
period of time. Results from reSldential well sampllng conducted
as part of the Supplemental RI concluded that the drink1ng water
from existlng wells 1n the vicinity of the slte was of acceptable
quality. Secondly, due to the complex nature of the fractured
bedrock aquifer system and the high concentratlons of a wide
varlety of contamlnants in groundwater, the techn1cal feaslbllity
of remed1atlng groundwater to a level in excess of 10-5 may be
limited. It should also be noted that remediation of the ground-
water to the 10-5 level represents a 99 percent, reduction from
eXlsting levels.
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The aquifer characteristics and level of contaminants in groundwater
limit the rate of restoration. At a maximum pumping rate of 40 pgm,
the groundwater can be restored to a 1 x 10-5 risk level within
10 years. A higher pumping rate will only induce water from
adjacent surface water bodies and will not restore the groundwater
more rapldly.
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2.
Consistency ~ Other Envlronmental ~
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Envlron~ental laws which are applicable or relevant and approprlate
to the recommended source control and management of migratlon
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alternatives at the Re-Solve site are:
Resource Conservatlon and Recovery Act (RCRA)
Clean Water Act
Safe Drinking Water Act
Executive Order 11990 (Protection of Wet~ands)
Toxic Substances Control Act (~SCA)
The Clean Air Act
As specified in ~he Alternatives Evaluation Section, the selected
remedy is expected to comply with The above laws.
The Resource Conservation and Recovery Act (RCRA) closure regulations
require closure by removal of waste, w.ste resldues and contaminated
subsoils which is equivalent to closure as a surface impoundment
or waste pi~e (40 C.F.R. 264 Supbart K and L)1 or closure as a
landflll by capplng and appropriate post-closure care (40 C.F.R.
264 Subpart !~). The proposed remediation at the Re-Solve site
attalns the general RCRA closure performance standards as specified
in 40 C.F.R. S 264.111:
The owner or operator must close the facility in a manner
that: .:~
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(b)
Minimizes the need for further malntenance7
Controls, minlmizes or eliminates, to the extent
necessary to protect human health and the environment,
post-closure escape of hazardous waste, hazardous constlt-
uents, leachate, contaminated run-off, or hazardous
waste decomposition products to the ground or surface
waters or to the atmosphere7 and
(c)
Complies with the closure requirements of Subpart G
including, but not limited to, the requirements of
S 264.178, 264.197, 264.228, 264.258, 264.280, 264.310
and 264.351.
The proposed remediation attains the general RCRA performance
goals by utilizing the relevant and appropriate sections of
closure by removal and closure by capping. Excavation and treatment
of PCB contaminated soils above 25 ppm will result in the removal
of a large majority of wastes and waste residues and it will
prevent the direct contact threat from those contamlnants.
The management of migration pump and treat option will minimize
and eliminate to the extent necessary the migration of contamlnants
from the site. The gravel cover, loam, seedlng and restriction
of on-site groundwater use will provide the necessary long-term
protection for public health and the environment.
The proposed remediation utillzes the relevant and appropriate
requirements of closure by removal and closure by capplng. EPA
feels that closure by removal and treatment of PCBs and groundwater,
attalns the goals of RCRA closure by mlnlmizlng the dlrect contact
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-70-
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threat and m1n1m1z1ng the m1grat1on of Contam1nants. To ensure
protect1on of publ1C health and the env1ronment, EPA bel1eves
that m1n1mal post-closure care (lnclud1ng, but not llm1ted to~
gravel cover, loam, seed1ng, mon1tor1ng and 1nst1tut1onal controls)
1S requ1red and that the relevant and appropr1ate RCRA post-closure
requ1rements are atta1ned.
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Regard~ng management of m1grat1on measures, the spec1f1c relevant
Federal regulat10ns are the RCRA Groundwater Protect1on requlrements
(40 C.F.R. 264 Subpart F), the Clean Water Act and the Safe
Drlnklng Water Act. The groundwater protect1on regulat10ns
requIre the settlng of groundwater protectIon standards whIch
must be protectIve of publ1C ~ealth and the envIronment. The
target levels of PCE, TCE and methylene chlorIde are sIte-specIfIc
levels that. the Agency has determIned wlll adequately protect
publlc health and the envlronment. The remedlatlon wIll attempt
to ach1eve these levels downgradlent at the pOlnt of complIance.
The p01nt of compl1ance 1S based on the extent of PCB contam1nat1on
at depth.
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A groundwater mon1tor1ng system w1ll be 1mplemented conSIstent
w1th 40 C.F.R. S 264.l00(d) to).determlne the effect1veness of
the groundwater remed1at10n system.
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The remed1at1on of groundwater 1S conS1stent w1th the U.S. EPA
Groundwater Protect10n Strategy (GWPS), whIch class1f1es the
aqu1fer at Re-Solve as Class IIA (current usage) and requ1res
the restorat10n of these a;u1fers. Th1S remed1at10n program
would also be conS1stent w1th the Commonwealth of Massachusetts
Groundwater Protectlon rules and regulatlons.
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As discused earlier, EPA believes that it 1S technically infeasible
to reduce PCB levels in groundwater with1n the waste management
area, to an acceptable risk level for use as a drink1ng water supply.
Because of this, drinklng water standards established under the
Safe Drink1ng Water Act (SDWA) are not relevant and appropriate
requirements within the waste management area. PCBs are not present,
however, in groundwater beyond the waste management area. Hence,
that groundwater can be restored to permit its use as a drinking
water supply and MCts, established under the SDWA, are relevant
and appr~prlate and will be ~ttained.
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Excavat10n, flll1ng and restorat10n of the wetlands w1ll comply
w1th the techn1cal 1ntent of Execut1ve Order 11990 - Protect10n
of Wetlands, the Clean Water Act S 404(b)(l) gU1del1nes and the
State Wetland Protect1on Act (310 CMR 10.00). The excavatIon
wIll be performed to m1nlm1ze the destructIon of the wetlands.
The remedIal actIon conta1ns components to restore the wetlands
whlch may result 1n the 1mprovement of the benef1c1al values of
the wetlands. The restorat1on of the wetlands after excavat10n
w1ll be performed cons1stent w1th the 404(b)(l) gU1del1nes, and
w1th EPA and State reV1ew of the des1gn of the m1t1gat10n meas-
ures. The Agency feels 1t 1S necessary to perform the excavatIon
to adequately protect publlc health and the enV1ronment.
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-71-
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EPA does not conslder the ~ PCB Spill Cleanup Policy
(Apr1l 2, 1987) as an ARAR for the slte. ThlS POllCY 1S prospective
in nature and establishes what EPA considers to be adequate
cleanup for the majority of situations when PCB contam1nat10n
occurs during activ1ties regulated under TSCA. It lS clearly
stated that existing sp11ls are excluded from the scope of the
policy.
U~der the TSCA Disposal Requirements (40 C.F.R. S 761), EPA
considers the criteria detailed in 40 C.F.R. 761.70, pertaining
to thermal destruction, to be applicable for site remedlation.
If lnclneratl~n is selected as the source control treatment
technology, treatment and disposal of the 25,500 cubic yards of
the PCB waste will be in accordance with these criterla.
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EPA does not consider the 50 ppm regulatory threshold to be an
ARAR or a cleanup standard for the slte. The establlshrnent of
th1s regulatory lim1t was based on economic and administrative
conslderatlons as well as human health and the environment. As
such, on a site-specific basis, it does not necesarily achieve
the object1ve of section 121 of CERCLA. Instead, 1n this case
EPA developed health-based cleanup standards for the site based
upon a rlsk assessment.
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Fur~er, ,EPA does not consider the performance requirements for
alternatlve treatment methods for destroY1ng PCBs (40 C.F.R.
S 761.60) to be an ARAR for the slte. Forty C.F.R. S 761.60
requires that alternative treatment methods achieve a level of
performance equivalent to S 761.60 incinerators or high eff1c1ency
boilers. The Agency, though, has determined that the level of
performance for chemical dechlorination (APEG), a method used to
detox1fy PCB mixtures in transformer fluids, 1S 2 ppm PCBs.
This clearly is not equivalent to the level of performance of
S 761.60 inC1nerators or high eff1clency boilers. Therefore,
the performance level for dechlorination w111 be 25 ppm PCBs,
the site-specific health-based cleanup standard determined to be
protect1ve of human health. Treating excavated sOlIs to a health-
based cleanup standard using an alternative treatment method 1S
conslstent with the intent of CERCLA.
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During the excavation and treatment of PCB contaminated soils,
and during the groundwater treatment, air emissions will be
monitored and all relevant Federal and State standards will be
attained. , Specifically, the National Ambient Air Quality Standards
(NAAQS) for particulate matter (PM10) will be met through the
specified techniques for excavation activities. An overview of
State ARARs can be found in Append1x A.
3. Cost Effectiveness and Utilization of Permanent,Solutions
and Alternative Treatment Technologies or Resource Recovery
Technologies to the Maximum Extent Practicable.
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The source so11s at the Re-Solve site are highly contam1nated
with PCBs and VOCs. PCBs, the pr1mary contaminant in the unsaturated
zone, are probable human carc1nogens and extremely perslstent in
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-72-
the envlronment. The sedlments in the wetland north of the slte
. ~nd the unnamed trlbutary are also contaminated with PCBs. One
composite sample of redfln pickerel and Amerlcan eel was found
to be contamlnated with PCBs in excess of the Food ,and Drug,
Administration's tolerance level of 2 ppm.
..
On-site
for the
bedrock
Some of
sOlIs are acting as a continuous Source of contamination
groundwater. Groundwater in both the overburden and
aquifer systems is primarily contaminated with VOCs.
the VOCs are carcinogens or Suspected carcinogens.
"
Contaminants in the overburden aq~ifer are predominantly dls-
charging to adjacent surface waters and in turn, migrating away
from the site. Residual contamlnation in the bedrock system has
migrated beyond the boundaries of the site.
DechlorinatIon is an alternative treatment technology that will
provlde a permanent solution to the PCB problem at the site.
Treatment of the PCB contaminated sOlIs in the unsaturated zone
to 25 ppm will reduce the risks posed to human health from dlrect
contact with on-Slte soils by signlficantly reducing the volume
and toxlcity of the contaminants. ThlS soil treatment process,
will also provide the added beneflt of treating a percentage of
the VOCs in the unsaturated zone, thus assisting in the cleanup
of groundwater by eliminating a significant source of contamination
to t~e groundwater.
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Excavation of PCB contamlnated sedlments above 1 ppm PCB and
treatment on-slte will also reduce the risks posed to fresh-
water aquatlc life associated with contact with these sedlments
and subsequent bioaccummulatlon. Freshwater aquatic llfe lnclude
both sediment dwelling organlsms and those at hlgher trophlc
levels. .
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In comparlson to on-Site thermal destruction (incineration),
dechlorination is more cost-effective while providing a similar
level of reliability and protectlveness. The prlmary difference
between the two treatment alternatlves is that dechlorlnatlon is
proven in the bench-scale level while incineration has been
proven on a pilot-scale and full-scale level. However, selectlon
of dechlorination is consistent with section l2l(b)(2) which
allows EPA to select an innovative technology, whether or not
such technology has been achieved in practlce at any other facility
or site. Dechlorination is also preferred by the public and the
Commonwealth of Massachusetts over incineration.
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Active restoration of the groundwater will be accompllshed uSlng
the best demonstrated available technology for treatment of
groundwater. The final unit processes will,be determined following
completion of the treatability studies scheduled to be conducted
during remedial design.
Treatment of the groundwater will permanently and signlflcantly
reduce the volume, toxicity and moblllty of the Volatlle organlcs
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-73-
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as well as reduce the mobility of the PCBs present in the saturated
zone sOlI matrix. Restoration of the aquifer to a 1 x 10-5
r1sk level-w1ll permit the groundwater beyond the waste management
area boundary to be used for drinking water purposes in the
future. However, EPA will require that institut10nal controls
restrict1ng groundwater use be implemented following complet10n -
of the remedial action. Institut10nal controls will be required
only for the area within the waste management boundary.
Further, restoration of the groundwater will elim1nate the threat
posed to public health and the environment from the current and
future extent of contam1nant migration in groundwater and surface
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The selected groundwater remediation alternative (MOM-2C) 1S
more costly than the-other two treatment alternatives evaluated
earlier, HOA-2A Heated Influent Air Stripping and HOH-4 Pretreatment
and D1sposal at a POTW. However alternatives Hmi-2A and ~tOM-4
alone are not effective 1n reducing the concentration of contam-
1nants to the target cleanup levels in a time perlod equivalent
to HOH-2C. The hlgh levels of TVO in groundwater (200 ppm TVO)
necess1tates the use of carbon adsorption to ach1eve a 99 percent
reduction in contam1nant level~ within 10 years of operation.
In c&ntrast, the no action alternative is not an appropriate
remedy. First, such a remedy would be unreliable and of questionable
effectiveness 1n terms of protectlng human health. Second, such
a remedy would be totally ineffective in terms of protectlng the
environment. Third, such a remedy does not comply wlth relevant
and appropriate requ1rements. Flnally, no action is exactly
what Congress dld not intend to encourage in creating a strong
statutory preference for remedles that destroy wastes.
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In addition, the containment optlon is not an appropriate remedy
because, over the long-term, there are no guarantees that such
containment will remain effective. Further, conta1nment wlll
not remove the soil contamination1 leachlng of these contamlnants
into the groundwater, partlcularly the VOCs, would cont1nue,
although at a reduced rate compared to present, unremediated
conditions. Failing to treat the groundwater would render the
groundwater in the vicinlty of the site unusable for drinking
water for a substantial period of time. The groundwater would
also continue to act as a source of contamlnation to off-site
surface waters.
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Based on information contained in the Administrative Record for
the Re-Solve site, the Agency considers that the selected remedial
action is conslstent with section 121 of CERCLA and utllizes
treatment which permanently and significantly reduces the volume,
toxicity and mobility of the hazardous substances at the site as
a prlnc1pal element. Further, the remedial action is protective
of human health and the environment, cost-effectlve and utlllzes
permanent solutions and alternative treatment technologies to
the maximum extent practicable.
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-74-
C.
Evaluation of Selected Remedy vs Other Alternatives
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The July 24, 1987 memorandum from the Assistant Administrator
for the Office of SOlld Waste and Emergency Response entltled
"Addltional Interim Guidance for FY'87 Record of DeCislon"
establishesnlne evaluatlon criteria which are to be used to
explain ~he rationale for selecting the chosen alternat1ve.
Certain of these criteria are mandated by CERCLA1 others derive
from the current NCP and existing RI/FS and ROD guidances.
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As described earlier, an lnitial screening of alternatives was
conducted using the process contained in the current NCP. This
approval was deemed acceptable because CERCLA requlrements are
either equal to or more stringent than those in the NCP. Hence,
screening on the basis of the current NCP would not eliminate
alternatlves that would be acceptable under CERCLA. That screening
process resulted 1n identification of 5 source control and 3
management of migratlon alternatives. Certaln features of these
alternatlves were then selected as components of the final remedy
described earlier. A comparison 'of the final remedy wlth these
alternatlves was conducted, based upon the nine (9) evaluation
criteria. The results are as,{ollows:
1. ~Compliance with Applicable or Relevant
and Appropr1ate Requlrements
Section 12l(d) of CERCLA, as amended by SARA, requires that
remedial actions comply with requlrements or standards under
Federal and State envlronmental laws. The requlrements that
must be complied with are those that are applicable or relevant
and approprlate to the hazardous substances, pOllutants, or
contaminants that remain on-S1te.
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All of the alternatlves, wlth the exceptlon of those for NO-Actlon
(SC-l and MOM-I), will meet all Federal and State ARARs. Pllot
studles will be required for the dechlorlnatlon process to 1dentlfy
the chemlcal constltutents of the byproducts (i.e., sldestreams)
and to determlne the degree of 'future management. If lt is
determlned that the residuals from the dechlorination process
must b~ disposed of off-site, shlpment of such residuals will be
in accordance with RCRA and DOT requirements. Trlal burns will
be conducted to meet RCRA and TSCA requirements for those alter-
natives utilizing thermal destruction, and analysls of residuals
will be conducted to determine necessary management.
The selected remedy meets all Federal and State ARARs. Because
of the innovative nature of dechlorlnation technology, the ROD
calls for addltional pilot-scale evaluatlon to assess the
implementability of th1S technology on a large scale and the
effectlveness 1n VOC reductlon. If such studles show that
dechlorination cannot be lmplemented to meet ARARs, the remedy
will be modlfled to provide on-slte incineratlon as a Substltute
technology.
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All alternatlves, except no action, as well as the selected remedy,
do requlre ldentical work in wetlands areas. Adequate steps can
be taken to minlmize any system impacts on the wetlands, and all
alternatlves include mltigative steps to comply wlth wetlands
requirements.
2.
Reductlon of Volume, Toxicity, or Mobility
, "
This evaluation criteria relates to
or reme~lal alternatlve in terms of
risks posed by the volume, toxicity
substances.
the performance of a technology
eliminating or controlllng
or mobility of hazardous
,
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The selected remedy will result in the treatment of 25,500 c.y.
of sOll and sed1ment contaminated prlmarily with PCBs and volatile
organics. Prel1m1nary results from a bench-scale stud1es 00
Re-Solve soils and pilot-scale study in Region II lndicate that
dech10rlnatlon will be successful in reducing PCB levels. Bench-
scale tests on Re-Solve sOlls, however, indicate uncertainty
about the extent ot reductlon of ot~er organic compounds.
The pllot studles necessary to scale up the PCB dechlorination
pr~ess ,will also be used to a~sess the degree of attendant VOC
reductlon. If the degree of VOC reduction is inadequate to allow
the groundwater pump and treat system to achleve its goal within
the estimated 10 year timeframe, various means of pre- or post-
treatment of soils will be investigated to provlde further, adequate
VOC reductlon. If such reduction cannot be achieved, the remedy
calls for substitutlon of on-site mobile lncineration, a proven
technology for destructlon of both PCBs and organics.
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Groundwater treatment called for in the selected remedy, as well
as ln several alternatlves evaluated for conslderation of management
of m1gration, wl1l reduce the volume of hazardous organlc substances
1n the groundwater (99 percent reductlon). Reduction of organ1c
levels will, 1n turn, render the PCBs 1n the saturated zone sOll
matr1x relat1vely 1mmob11e.
"
A pilot treatability study will be conducted to evaluate the
effect1veness of air stripping to remove semi-volatiles, such as
ketones. If needed, heated air stripping will be incorporated
into the final groundwater 'treatment train to assure adequate
removal of ketones.
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Short-Term Effectiveness
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Short-term effectiveness measures how well an alternative is
expected to perform, the t1me to achieve performance and the
potential adverse impacts of its implementation.
The source control component of the selected remedy requires
e'xcavation and treatment by dechlorination of 25,500 c.y. of PCB
contaminated sOll and sediment. Implementation will require an
est1mated 2 years, exc1uslve of deslgn, bidd1ng and award tlme.
Excavatlon could result in the release of airborne volatl1e
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organlcs and PCB contaminated f~gitive dust. To mitlgate thlS,
excavatlon wlll be restrlcted to sheet plllng vertlcal cuts.
Addltlonal suppressant techniques, such as foam or water spray,
may also be needed. Alr monitoring will be conducted at the
perimeter of the slte for VOC; PCB vapor and PCB particulates.
Excavation of sediment in the wetlands will result in unavoldable
lmpacts and disturbances to wetland resource areas which may lnclude
destruction of vegetation, loss of indigenous species and downstream
migration of PCBs. To minimize such impacts, remedlation would
be restrlcted to seasonal low water periods (late summer-early
fall). This constraint will require careful schedullng of the
project to avoid downtime while walting for such low water periods.
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Because dechlorination is an innovative technology and is currently
being implemented on a pilot-scale level, there may be delays in
project implementation if the number of full-scale unlts are limlted.
The management of migration component of the selected remedy is
alternatlve MOM-2C, Precipitation/Alr StrlPPlng/Actlvated CarbonI
Filtration. This component will take an estimated 10 years to
complete.. Prior to lmplementation, however, a full-scale performance
test and pilot treatability study will be needed to determlne
the maXlmum ground~ater pumpi~g and recharge rates and other
deqgn c,rlterla and to verify 'effectiveness of the treatment
train for removal of ketones. Heated air stripping, a component
of (alternative MOM-2A), may be required if so lndicated by the
pllot treatabllity study. Air, groundwater, surface water and
wetlands monitorlng wlll be required durlng operation to assure
no adverse lmpact to health or the environmel." and to moni tor
the effectiveness of the treatment system. If negative lmpacts
are observed, pumping rates may be reduced to assure extractlon
of groundwater does not detrimentally impact wetlands.
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The no-action alternatlve (SC-l and MOM-I) could be implemented
qUlckly wlth mlnlmal lmpact on health and the environment. The
operation and malntenance period for the alternatlve, though,
including fencing, gradlng, seedlng and lmplementlng a long-term
monltorlng program, would be greater than for other alternatlves.
Alr monitoring would be required during revegetatlon and gradlng
to ensure that levels do not pose risk to on-site workers and
nearby residents. Thus, this alternative requires monitoring
for at least 30 years. Reduction of contaminant levels in soils
and groundwater to levels protective of human health and the
environment by natural attenuation ~ould take as long as 400 years.
Both the on-site and off-slte Thermal Destruction/Incineration
sour'ce control alternatives requlre excavatlon of contamlnated
sOlIs and emlssion controls as indlcated for the selected alternative.
Both on- and off-slte incineration are proper, effective technologles.
On-site inclneration will take 3 years to implement, off-site an
estlmated 2 years. However, off-site incineration could be faced
wlth extensive delays due to the limlted commerclal inclnerator
capaclty natlonwlde. Further, off-slte lnClneratlon will result
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1n greatly increased truck traffic to and from the slte. As many
as 4000 18 wheel truckloads of contam1nated soil would be
transported away, and an equal number would be required to haul
clean backfill to the site. Safety measures would be needed to
'prevent spills on highways and prevent contam1nation of the Fall
River ReserV01r, which is located along the truck route.
Mobile inc1nerat1on systems are commercially available, but there
may be delays 1n securing a system due to the current limited
capacity in the industry. EPA anticipates l~creased availability
in the future, but this is unknown at the moment. A test burn
would be conducted prior to operation to assure the effectiveness
of' the selected technology on Re-Solve soils, and both stack and
ambient air monitoring would be conducted to ensure protection
of publ1C health on- and off-site.
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Source control alternat1ve SC-7c (Encapsul~tion, In-Situ Soil
Flush1ng and Source Material Treatment) calls for construct1on of
a sOll bentonite slurry wall, excavation and destruction by one
of the source control technolog1es of a lesser volume of sOll and
sediment, and soil flush1ng of the remain,lng soils. Construct1on
of a slurry wall at depths found at Re-Solve could be 1mplemented
quickly, but may not be effective due to problems with seal1ng
j01nts 1n fractured bedrock. The required sOll excavatlon will
ralSe the same concern as other source control alternatives, but
due to the greatly reduced volume, should be more easily mon1tored
and controlled. Impact upon the wetlands would be the same. In-
situ S011 flush1ng will require bench-scale and p110t-scale tests
to ver1fy 1tS effect1veness. Th1S alternat1ve could requLre
operat1on for as long as 40 y~ars to achieve the remed1at1on goals.
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Long-Term Effectiveness and Permanence
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Long~term effectiveness and permanence addresses the long-term
protect1on and rel1abllity an alternative affords.
w1th the exception of the no-act1on alternative, each of the
al te'rnat 1 ves, 1nc lud1ng the selected remedy, should prov1de
equ1valent protect1on of public health and the environment, because
each can be designed to ach1eve the remed1ation goals establ1shed
for the slte. None of the alternatives result in complete
destruction or removal of all waste, so each would require a
review every five years, as mandated by CERCLA section l21(c).
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The no action alternative would not be permanent, effective or
reliable since contaminants would continue to move from soil into
groundwater and on into the surrounding env1ronment. The mon1tor1ng
program would track, but not control, such movement. Fences,
warning signs and sim1lar barriers to limit exposure would require
period1c publ1C awareness efforts to monitor effectiveness.
The use of a slurry wall, to conta1n water, as part of source
control alternat1ve SC-7c may not be rel1able 1n the long-
term. Leach1ng, elther, under the wall or through the wall 1tself,
as a result of long-term contact between the wall and certa1n
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, mob1le organic compounds, may release contaminants 1nto the
environment. Although bench- and p1lot-scale stud1es would be
conducted as part of des1gn, there is some quest10n as to the
long-term reduct10n 1n PCB levels that would'be attainable through
th1S technology.
Both on-site and off-site Thermal Destruction/Incineration would
be effect1ve, permanent and reliable alternatives, to the extent
that the contam1nants 1n the soils would be destroyed. Simllarly,
all of the groundwater treatment technologies cons1dered would
result ln effective and permanent destructlon of contaminants.
All show the same difficulty with reliability in that all requ1re
design of a groundwater extract10n system that would result in
all contam1nants be1ng processed through the treatment traln. It
is possible that some contaminated groundwater hot spots would
escape extract10n and treatment and remain in the environment.
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The selected remedy shares these problems in common with the other
alternatives. If design studies lndicate a concern about the
effectiveness of dechlorinatlon, lncineratlon would be Subst1tuted.
The rema1n1ng element, however, should be as effect1ve and rel1able
as the other alternatives.
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5. ~Impl~mentab1lity
Implementab1l1ty cons1deratlons address how easy or dlfflcult,
feasible or lnfeasible it would be to carry out a given alternatlv'
from deslgn through constructlon and operation and maintenance.
The lmplementability of an alternat1ve 1S evaluat~d 1n terms of
techn1cal and admini~trat1ve feas1bllity, and ava1labllity of
needed goods and serV1ces. The a1ternat1ves evaluated here are
all techn1cally feaslble. However, there are some m1nor lmplemen-
tation problems assoclated w1th each of the alternat1veS.
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The use of 1nnovatlve technologles 1n the selected remedy (i.e.,
dechlorlnatlon) and sOll flushlng ln source control alternative
SC-7c are dependent on the outcome of needed pllot and/or bench-
scale stud1es. Both concepts, however, would rely on readlly
avallable chem1cals and equipment. EPA is aware of one company
that 1S planning to bU1ld a full-scale dechlor1nat10n unit by the
spring of 1988.
Off-site Inclneration, SC-14, will be dependent upon adequate
capacity at a commercial RCRA/TSCA incinerator, and upon the
availability of facillties in compliance with all regulatory
requirements, as required by'section 121 of CERCLA and EPA's
Off~slte POllCY. At present, there are only three facillt1es
that will accept PCB-contamlnated soils for incinerat10n and
these wlll only accept small quantit1es. Therefore, the large
volume involved at Re-Solve would requlre a phased delivery
schedule.
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inc1nerat1on system. Such systems are now commerclally ava1lable
and there are "no anticlpated d1ff1cult1es in obta1n1ng the
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-79-
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approprlate equlpment.
scale operatlon of such
sltes has been limited,
'periods of downtlme.
It should be noted, however, that full
transportable unlts at hazardous waste
and unlts have experlenced extended
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The on-slte groundwater treatment system proposed in alternatlves
MOM-2a and MOM-2c, as well as in the selected remedy, are standard
t~chnologies and should be readlly available.
Alternative MOM-4, which calls for pretreatment and disposal of
contamlnated groundwater at a POTW, would be subject to permit
requlrements, both for the discharge to the POTU and for the
POTW effluent itself. Extenslve modification of the existing
POTU could be required to sat is fy such requireme nts. Thus, EPA' s
ability to implement this alternative is hlghly questl0nable.
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State Acceptance
The State acceptance addresses the concern and degree of support
that the State government has expressed.regardlng the remedlal
a~ternative being evaluated.
The Commonwealth of Massachusetts has reviewed the varl0US
alternatlves and has indicated' its concurrence with the
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selected' remedy.
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7.
Community Acceptance
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ThlS evaluatlon criterla addresses the degree to which members of
the local community support the remedlal alternatives belng
evaluated.
, .
During the public comment perlod on EPA's proposed Plan, a number
of commentors (Sierra Club, Town of Dartmouth, Re-Solve Citlzens'
Advlsory Commlttee, and westport Rlver Defense Fund) supported
EPA's chOlce of dechlorination and groundwater treatment for the
Re-Solve slte. The Sierra Club also supported lnc1neratl0n as
the backup optlon.
The local community has reservations about potential air emiSS10ns
from excavatl0n and handllng activitles and strongly favors
stringent air monitoring and the use of mitigat1ve measures to
control any unavoidable emlssions.
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Costs are evaluated ln terms of remedial action costs and
replacement costs.
The present worth cost for the source control component-of the
selected remedial actl0n is based on treatment of 25,500 c.y. of
PCB contaminated sOlls and sedlments to a level of 25 ppm PCB.
EPA estimates that it wlll take two (2) years to treat thls volume
by dechlor1natlon. The est1mated present worth cost is $9,237,000.
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Included 1n th1s cost estimate 1S an add1t1onal 10 percent
cont1ngency. Th1S 1S 1ncluded because dechlor1nat10n is a new
and 1nnovative technology and as such, requires that a cont1ngency
be provided dur1ng scale-up to accommodate var1able sidestream
process requirements.
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By comparison, the estimated present worth cost to treat the same
volume by on-site 1ncineration, over a two(2) year period, 1S
$16,963,000. The cost/c.y. est1mate used to derive th1S present
worth estimate 1S $400/c.y. Th1S cost/c.y. est1mate 1S. for
cap1tal cost and operation and maintenance and does not include
costs for excavat10n and management of residuals.
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The estimated present worth cost for off-site 1ncineration of
2!,500 c.y. of PCB contam1nated soils and sed1ments is $80,000,000.
Th1S est1mate could be subject to change, though, depend1ng on
the ava1labil1ty of an off-s1te fac11ity.
For both the no action alternative and alternat1ve SC-7c, stud1es
would have to be performed every f1ve years to ensure the cont1nued .
effect1veness of the containment component.
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As part of the selected remedy, groundwater would be treated to
redyce contarn1nants to levels Wh1Ch w111 result 1n an excess
cancer r1sk of IX 10-5, assum1ng add1t1v1ty. The est1mated per10d
of t1me to achieve th1S level of remed1at10n 1S 10 years. The
est1mated present worth cost of the groundwater remed1at10n
component (MOM-2C) of the selected remedy 1S $10,674,000.
The selected groundwater remediat10n alternative 1S more costly
than the other two treatment alternat1ves evaluated earl1er,
MOM-2A, Heated Influent A1r Str1pp1ng and MOM-4, Pretreatment and
Disposal at a POTW. Alternatives MOH-2A and MOM-4 alone are not
effect1ve 1n reduc1ng the concentrat10ns of contam1nants 1n
groundwater to the target remed1at10n levels in a t1me per10d
equ1valent to MOM-2C. The h1gh level of contam1nat10n 1n
groundwater necess1tates the use of carbon adsorpt10n near the
end of the remed1at1on per1od, to ensure atta1nment of the target
cleanup levels.
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9.
Overall Protection of Human Health and the Environment
Protection of human health and the environment 1S the central
mandate of CERCLA as amended by SARA. Protection is achieved by
reduc1ng threats to acceptable levels and tak1ng appropriate
action to ensure that, 1n the future, there will be no unacceptable
risks to human health and the environment through any exposure
pathways.
All alternat1ves that underwent detailed analys1s in th1S ROD
prov1de, to some degree, protect10n of human health and the enV1ron-
mente However, the selected remedy, on-s1te dechlorinat10n of
25,500 c.y. of PCB contam1nated sOlls and sed1ments to a treatmenr
level of 25 ppm PCB and remed1at1on of groundwater to an excess
cancer r1sk of 1 X 10-5, prov1des the highest degree of protect10n.
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Dechlorlnatlon, although lnnnovatlve, is a treatment process that
has been demonstrated on a pilot-scale level to be effectlve ln
reducing PCBs 1n ~olls to levels that are protectlve of human
health and the environment. Excavat10n and treatment of PCB
contam1nated soils and sedlments, at concentrations greater than
25 ppm and 1 ppm, respectively, will reduce the volume and toxiClty
of the hazardous substances at the site.
On-slte inc1neration would offer a slmilar level of protection as
that of dechlorlnation. The primary difference between the two,
excluding cost, is that dechlorinat1on is a closed system (l.e.
no em1SS1ons from the unit) and inc1nerat1on produces a1r em1SSlons.
It would be necessary to monitor a1r emissions from the incinerator
during operation to ensure that the levels do not pose a rlsk to
on-s1te workers and nearby res1dents.
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Alternative SC-l4 Off-site Inc1nerat1on would offer a slm1lar
degree of protect1veness on-s1te, but dur1ng lmplementat10n noise
and truck trafflc ln the area would 1ncrease slgnlficantly. In
addlt10n, the potential threat of an acc1dent dur1ng transport of
materials places the dr1nk1ng water supply of Fall River 1n danger.
Alternative SC-7C would have the least problems dur1ng the remedlal
ac~on implementation phase and would reduce the r1sks posed to
human health and the env1ronment from d1rect contact. But, th1S
alternatlve would not Slgnlficantly reduce the volume, tOXlclty
and mobll1ty of hazardous substances prese~t at the slte. Leaching
of these contamlnants 1nto groundwater, particularly the VOCs,
would contlnue, although at a reduced rate compared to the present
unremediated cond1tl0ns. Further, over the long-tern, the
effect1veness of contalnment is 1n questl0n.
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The groundwater treatment process represents the best demonstrated
available technology for the treatment of the on-s1te contaminants.
p1lot stud1es will be conducted pr10r to 1mplementatlon of the
remedy to determlne the appropr1ate un1t process that wl1l be
used to remed1ate groundwater. Treatment of groundwater wlll
permantly and Slgn1f1cantly reduce the volume, tox1Clty and
mob1l1ty of the volat11e organ1cs as well as reduce the mob1l1ty
of the PCBs present in the saturated zone soil matr1X.
In contrast, alternative MOM-4 1S protective and effect1ve in
reducing contam1nant levels, but the ava1labil1ty of an off-site
POTW to accept the effluent remains uncerta1n.
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Based on informat1on available to evaluate the f1ve (5) source
control and three () management of m1gration alternat1ves against
the n1ne (9) cr1teria, EPA has concluded that the selected remedy
1S protect1ve of human health, atta1ns all appllcable or relevant
and appropr1ate requ1rements and 1S cost-effect1ve. Add1tionally,
because the selected remedy employs dechlor1nat10n and on-slte
treatment of groundwater to el1m1nate the pr1nc1pal threats at the
Slte (l.e. PCBs 1n sOlls/sed1ments and VOCs 1n groundwater), th1S
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remedy also satIsfIes CERCLA'S preference for remedIes whIch
employ treatment as theIr prIncIpal element to reduce the volume,
toxIcIty or mobllty of hazardous substances at the sIte.
Although thIs remedy wIll requIre measures to control possIble
rIsks related to ItS constructIon and operatIon, the Agency's
analysIs IndIcates that all of these rIsks can be satIsfactorIly
controlled. AddItIonally, any short-term rIsks appear heavIly
outweIghed by the long-term effectIveness and permanence thIs
remedy wIll provIde. The Agency belIeves thIs remedy for thIs
sIte avoIds the long-term uncertaIntIes assocIated wIth land
dIsposal, provIdes a permanent solutIon and utIlIzes alternatIve
treatment technologIes to the maxImum extent practIcable.
~
. "'. . -I - -
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-83-
VII State Role
The role of the Commonwealth of Massachusetts 1n th1S Federal lead
slte 1S mult1ple. The State reV1ews documents to determ1ne 1f
they are 1n compl1ance w1th appl1cable or relevant and appropr1ate
State env1ronmental laws and prov1des comments on all EPA funded
stud1es at the slte. . .
The commonwealth of Massachusetts concurs w1th the selected remedy
for the Re-Solve, Inc. slte located 1n North Dartmouth, Massachusetts.
A copy of the Commonwealth's evaluat10n of the selected remedy's
cons1stency w1th M.G.L. ch. 21E, as amended 1n November, 1986,
and declarat10n of concurrence 1S in Append1X B.
The Commonwealth of Massachusetts w1ll provide:
o
10 percent of the cap1tal cost of the selected remedy:
10 percent of the operat1on and ma1ntenance costs throughout
the lmplementatlon of the remedy: and
o
o
Cost for long-term monitor1ng and other act1v1t1es followlng
completlon of the selected remedy.
. .'
. -," ." - "
'", - ,","
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:- .'," ' .' '. \ ,-.. . "', ,"
-------
ill NOTES
1. Envlronmental protectlon Agency (EPA). 1980. Amblent Water
. Quallty Crlterla for Polychlorinated Blphenyls. Offlce of Water
Regulatlons and Standards, Crlteria and Standards D1V1S10n,
WaSh1ngton, D.C.' EPA 440/5-80-088.
2. ThlS alternat1ve represents the comblnat1on of several treat-
ment/handl1ng technologies. The technolog1es, as 1nd1vldual
processes, would not treat the contamlnatlon to a level
comparable as that of the other proposed alternatlves. As
opposed to screenlng out these technologies from further
evaluat1on,the SC-7 In-Sltu 5011 Treatment alternatlve has
been d1vlded lnto three sub-alternatlves. ThlS provldes for
each sub-alternatlve to progresslvely bUlld on the level of
effectlveness prov1ded ~y a lower level sub-alternatlve. For
the purposes of the ROD, SC-7cJ Encapsulatlon, In-Sltu 5011
Flush1n'g and source Materlal Treatment w1.11 undergo detalled
analys1s. .
3. Excavat10n of 64,000 CUb1C yards of PCB contamlnated sOlls and
sed1ments and assoc1ated costs are inherent to all source control
alternatlves contalnlng treatment as a prlnclpal element (i.e.,
SC-4 Dechlorlnatlon and SC-14 Off-slte Inclneratlon). A lesser
volume of contamlnated sOlls and sedlments lS treated ln alter-
- nat1ve SC-7c, but the same excavatlon technlques descrlbed
hereln shall be utlllzed.
4. Remed1at1on of PCB contam1nated sed1ments 1n wetland areas and
assoclated costs are 1nherent to all source control alternatives.
Alternatlve 5C-12, Sedlment Removal and Treatment, was the only
alternatlve for the treatment of PCB contamlnated sedlments
that emerged from the lnltlal screenlng step and was lncorporated
as a component alternatlve for each source control alternatlve.
5. These Federal and State publlC health and envlronmental requlre-
ments pertalnlng to remedlatlon of PCB contamlnated sedlments
are also applicable or relevant and approprlate for all source
control alternat1ves, SC-4,' SC-7c and SC-14.
6. Refer to the evaluatlon of alternatlve SC-2, On-s1te Thermal
Destructlon, for a more detalled dlSCUsslon on the method for
excavatlon of contamlnated sOlls and sedlments at the Re-50lve,
Inc. slte.
7. Ib1d.
/
8. The effluent pOl1Sh1ng system described as part of this alter-
nat1ve 1S the same for alternatlve MOM-2C Carbon Adsorpt1on.
9. The approach used to develop the range of cleanup goals for the
Re-Solve, Inc. slte lS conslstent wlth EPA GU1dance entltled
Development ~ Advisory Levels ~ Polychlor1nated B1phenyls
b~~~~~ ~~e~~~lthP~~~a~~~l~~n;~~t:~P~:~~:s~:~~~s~~~tl~~~~P'
.,.
,',r .
,..
",I,;
. ..
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-'
-------
10.
11.
12.
13.
14.
15.
16.
17.
'.
~
END NOTES (Cont'd)
Long, E.R., and Chapman, P.M. 1985. A sed1ment qual1ty tr1ad:
Measures of sed1ment contam1nat1on, tox1C1ty and 1nfaunal
commun1ty compos1t1on 1n puget Sound. Mar. Pol1ut.
Bull. 16:405-415. Chapman, P.M. 1986. Sed1m~nt qual1ty
cr1ter1a from the sed1ment qual1ty tr1ad: An example.
EnV1ron. Toxicol. Chem. 5:965-976.
Tetra Tech. 1986. Development of Sed1ment Qual1ty Value for
Puget Sound. F1nal Report. Prepared for Resource Plann1ng
Associates under U.S. Army Corps of Eng1neers, Seattle D1str1ct,
for the puget Sound Dredged D1sposal Analys1s and puget Sound
estuary Programs. September 1986. 128 p.p. and append1ces.
Th1bodeaux, L.J., Re1ble, D.D., and Fang, C.S. 1986. Transport
of Chem1cal Contam1nants 1n the Marine Env1ronment Orig1nat1ng
from Bottom Depos1ts -- A V1gnette Model. In "Pollutants 1n a
Multlmed1a Env1ronment," Ed. by Y. Cohen. Plenum Publ1sh1ng Co.,
New York.
EnV1ronmental Protect10n Agency (EPA). 1987. ReV1ew and Develop-
ment of Methodolog1es for Est1mat1ng Exposure to D1ox1n. The
Exposure Assessment Group~ Off1ce of Health and Env1ronmental
Assessment. Off1ce of Research and Development. January 1987.
Env1ronmental Protect1on Agency (EPA). 1980. Amb1ent Water
Qual1ty Cr1ter1a for Polychlor1nated B1phenyls. r
ronnolly, J.P., and Thomann,R.V. 1986. WAST OX , A Framework for
Modellng the Fate of TOX1C Chem1cals 1n Aquat1c EnV1ronments.
Part 2: Food Cha1n. Prepared for EPA Envlronmental Research
Laborator1es at Gulf Breeze and Duluth. .
Letter from Lee M. Thomas, Adm1n1strator, U.S. EPA to Honorable
James J. Flor1o, House of Representatlves, regard1ng the Agency's
1mplementat10n of the Superfund Amendments and Reauthor1zat1on
Act of 1986 (SARA~.
R1ce, Cl1fford P. and Wh1te, Dav1d S. 1987. PCB Avallablllty
Assessment of Rlver Dredglng USlng Caged Clams and F1Sh.
Envlronmental TOXlcol. Chern. 6:259-274.
,',r
,'" "," ., .
, .
. "',.
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,.'
"
'.
" .
. r
'.
r
-'
AppendlX A
AppendlX B
AppendlX C
;, . .' ",", ,-. .
Appendices
Appllcable or Relevant and Approprlate
Requlrements for the Commonwealth
of Massachusetts
State Evaluatlon and Concurrence Memorandum
Data Base - Flgures and Tables
~':':" .' ,t-, ~ .." -:: - --. '.
. ~', " . :" ";.
. . '.~'"
. .,'.
, ..
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APPENDIX A
Appllcable or Relevant and Approprlate
Requlrements for the Commonwealth
of Massachusetts
~ -'
-
, .
.' }.
,"' :.','
.' . ..:. .' : ~ ~ ...
. .' ," .
. , ',' .
. .'
. .' .,~. . --: ,': : ,;:,,:: 1.: ':',', J ::. :..~.-."." :', .:\, ;'.
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~
"
S. Russ.1I Sylva
Commissioner
(817) 282.S8S 1
. u
...
f7k ~ 0/
lffzea~~a/($~~
q)~a/lff~~~g~tj,
~Uud"Nz, 0/ ~ O/#'adk
tJ~~vw.c..9'kd 1J~~. IJ.tiIJ3
Aucult 31. 198'7
Linda Murphy. Chief
Massachusetts Waste Manaieaent Branch
U.S. Environaental Protection AienCy
J.P. Kennedy Pederal Buildini
BOlton. MA 02203
Dear Ms. MurphY:
The Departaent of Environaental Qual1ty Eniineer1ni (the Departaent) has
reviewed the June 1987 Draft Feasibility Study (FS) for the ReSolve Pederal
Superfund SIte 1n Dartaouth. Massachusetts. The purpole of thil letter 1s to
ident'ify the Depa~aent's '-applicable or relevant and appropriate Itandards.
. liaitations. criteria. and requireaents" (ARAKs) for the 8ite. A preliainary
li8t of the Departaent's ARAKs was liven to EPA 1n early 198'7 and 1ncluded 1n
the draft PS on Table 2-1. The Departaent requests that the lilt of State
Requlatlons be updated to include Table 1 attache~ to this letter.
The Departaent understands that tor work conducted on-8ite. 8ubstantive
requ1reaent. of these reculations are ARARs and not the procedural/adaini.trative
requireaents (i.e.. Pederal. State. and Local peraits) of the reculation..
In an atteapt to provide inforaation on each item li8ted in Table I. a short
luaaary Itatinl the authority and purpole for each reculation il included in
Table II. The suaaaries in Table II deaonltrate that Itandards. requireaentl.
or criteria' in the reculationl are proaulcated under State environaental laws.
..'
The DepartaeDt baa reviewed the alternatives described in the draft PS.
Table III pre8eata the Departaent'8 deteraination of ARAKs allociated with
environaeat81 aedla iapacted by activitiea for each alternative leparately
di8culled in Section 4 of the draft PS.
Section 121(a) and (b) of CERCLA. as ..ended by SARA. establish requireaents
for the decree of cleanup for reaedial actions at Pederal Superfund litel. In
addition to other criteria. the aaendaents require that reaedial actions on-site
Ihall attain Pederal ARARs and aore Itrinient State ARARs. Table IV includes
the list of the aore strinient State ARARs for the ReSolve site.
~
-'
-------
M. Bohman/Tables I and IV
AUlUst 31, 1987
Pale Two
In addition to the ARARs lilted in Table IV, the Depart.ent's review of
draft desiln plans and Ipecifications for the lelected re.edial action will
identify conditions necellary to aiticate the iapact of the construction project
to the environ.ent. Conditionl identified durinl the.Depart.ent's review of the
project Ihould be included in the Ipecificationl tor the project. All pollution
control Iyste.s are required by law to be approved by the Depart.ent.
Finally, all Superfund lites are lubject to M.G.t. c. 21E. Chapter 21E is
the State'l reneral Itatutory authority with relpect to reculatinr releases of
hazardous .aterials and oil and therefore can not be waived throurh the ARAR
procell .
The Depart.ent, pursuant to M.G.t. c. 21E, .ust reco..end an approach for
the lite that is consistent with the Itatute. Pursuant to M.G.t. c. 21E, the
lelection of a per.anent re.edy is the loal for cleanup of dispolal lites.
Under' 3A(q) of Chapter 21E a 8peraanent lolution" il a .easure or coabination of
aealures that, at a ainiaua, will attain a level of control for each contaainant
at and around the lite 10 that. no coataainant of concern will present a
lirnificant or otherwile unacceptable rilk of daaare to health, aafety, public
welfare, or the environaent. The Itatute allo requires that where feasible,
aeasures aust reduce contaainants to a 8level that would exist in the absence 0'
the dilposal"site of concern.8 An evaluation of EPA'I reco..ended lelected
alternative for the lite to deter.ine co.pliance with the require.~nt of M.G.L.
c. 21E is underway. It is anticipated that a final deteraination will be aade
by September 10, 1987.
This list is the Depart.ent's first co~prehensive atteapt to establish a
list of ARARs under the SARA aaendaents. I understand this .ay also be one of
the first such compliations EPA Rerion I has received fro. the New Enlland
States. As such we lo~k forward to workinl with you on any questions you aay
have. Por additional inforaation please contact Robert Bois at 292-5833.
;;JZ~7t
!d8ond Benoit, Deputy Director
Office of Incident Response
EB/lrw
Attachaents
cc: Willard Pope, OGC
Robert Donovan, SERO
Richard Cavalnero, EPA
Bruce Maillet, DAQC
Willi88 Gaulhan, DWPC
Pat Deis, DWS
Gary Clayton, Wetlands/Waterways
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~.
TABLE I
State ReiUlations.
1.
10S CMR Depart.ent Public Health
10S CMR 670.000. -Rilht to Know"
(a)
2.
301 CMR Executive Office of Environ.ental Affairs
301 CMR 11.00. Massachusetts Environaental Policy Act ReiUlations
(a)
3.
310 CMR Depart.ent of Environaental Quality Enlineerine ReiUlations
(a)
4.
310 CMR 6.00. Aabient Air Quality Standardl for the Co..onwealth of
Massachusetts
(b)
310 CMR 7.00. Air Pollution Control
(c)
310 CMR 9.00. Adainistration of Waterways Licenses
(d)
310 CMR 10.00. Wetlands Protection
- ,
(e)
310 CMR 19.00, Disposal of So\id Waste by Sanitary Landfill
(f)
(I)
310 CMR 22.00. Drink1nl Water ReiUlationl
310 CMR 27.00. Underlround Water Source Protection
(h)
(1)
310 CMR 30.00. Hazardous Waste ReiUlat10ns
310 CMR 33.00, I.ple.entation of M.G.L. c. 111P. E.ployee and COllJllunity
-Richt to Know"
314 CMR Malsachulettl Water Pollution Control ReiUlation~
(a) 314 CMR 3.00. Surface Water Dilcharle Per.it Prolraa
(b) 314 CMR 4.00. Surface Water Quality Standards
(c) 314 CMR :5.00. Groundwater Dhcharee Per.it Prol1'am
(d) 314 CMR 6.00, Groundwater Quality Standards
(e)
314 CMR 7.00, Sewer Systea Extension and Connection per.it proeram
.' .' ."
. -," . ~'.'.I..'
'. .'-.
. "
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s.
.
.. 2 .
(t)
314 CMR 9.00. Certification tor Dred&in&. Dred&1ni.Material Disposal.
and Pillini in Waters
(&)
314 CMR 12.00. Operation and Maintenance and Pretreataent Standards tor
Waste Water. Treataent Works, and Indirect Discharies
441 CMR Departaent ot Labor and Industries
(a)
441 CMR 21.00, Worker .R1&ht to Know"
Applicable statutes are listed in Table II
-------
1(a)
2(a)
3(a)
3(b)-
3(C)
3(d)
.,' -'
TABLE 11
Authority and Purpose
105 CMR 670.000 reculations are adopted by the Departaent of Public Health
pursuant to the authority !ranted it by M.G.L. C. 111P, I 2. The
reculations establilhes the Massachusetts Subltance Lilt and aaendaents of
reculated lubstances, trade lecretl and research lab exeaptions. The loal
of the reculations is to protect public health by providinl and
encouralinl the !reatelt pOlsible transailsion of health and lafety
inforaation concerninl toxic and hazardous substances.
301 CNR 11.00 reculationl lovern the iapleaentation of the Massachusetts
Environaental Policy Act, M.G.L. C. 30. II 82-62H. These reculations pro-
vide a iubstantive basis to ule all feasible aeans or aeasures to av01d or
ain1a1ze adverle env1ronaental iapact in coapliance with environaental
standards for decisions aade in coapliance with M.G.L. c. 30. I 61.
310 CMR 6.00 reculations are adopted by the Departaent pursuant to the
authority !ranted it by M.G.L. c. 111. '142(d). The reculations let pri-
aary and secondary air quality Itandards for certain pollutants.
310 CMR 7.00 reculations adopted by the Departaent purluant to the
authority Iranted it by M.G.L. c. 111. II 142(a)-142(j) and M.G.L. c. 21C.
II 4 and 6. The purpole of the reculations are to prevent the occurence
ot conditions of air pollution where luch do not exist and to facilitate
the abateaent ot conditions of air pollution where and when luch occur.
310 CMR 9.00 reculations are adopted by the Departaent pursuant to the
authority Iranted it under M.G.L. c. 21A. I 2 to iapleaent M.G.L. c. 91.
II 1-63 and M.G.L. c. 21A. II 2. 4. 8. and 14. The relUlations establish
procedures. criteria and Itandards for the unifora and coordinated admi-
nistration of the provision of M.G.L. c. 91. work (dredlinl etc.) that
takes place in a waterway (stream. river).
310 CMR 10.00 reculations are adopted by the Department pursuant to the
authority Iranted it under M.G.L. c. 131. I 40. The reculations establish
procedures. criteria. and Itandards for work in a wetland (dredlinl.
alterinl. etc.) lubject to the protection under M.G.L. c. 131. I 40.
3(e)
310 CKR 18.00 reculationl are adopted by the Departaent pursuant to the
authority rranted it under M.G.L. c. 111. I 150A. The reculations
establish rules and requireaentl for lolid waste dilpolal facilities.
3(t)
319 CMR 22.00 reculations are adopted by the Departaent purluant to the
authority !ranted it under M.G.L. c. 111. I 160. The reculations
establish Itandards and requireaents deeaed necessary to prevent pollution
and to assure the lanitary protection of water used as lources of public
water lupply and to ens~re the delivery of fit and pure water to all con-
luaers.
3(1)
310 CMR 27.00 reculation are adopted by the Departaent pusuant to the
authority Iranted it under M.G.L. c. 111. I 160; c. 21. I 27. The rerula-
tions lovern any under!round injection of hazardous wastes. of fluids used
'.' :,.-.-.,
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4(b)
4(C)
C(d)
4(e)
.~
~
.2.
for extraction ofiainerals, oil, and enerlY and certain other fluids with
potential to contaainate eroundwater in order to protect undereround sour-
ces of drinkine water.
3(h)
310 CMR 30.00 reculations 'are adopted by the Departaent pursuant to the
authority ,ranted it under M.G.L. c. 21C, 15 4 and 6 and M.G.L. c. 21E, 5
6. The reculatio~s establish rules and requireaents for the eeneration,
storace, collection, transportation, treataent, disposal, use, reuse, and
recycline of hazardous aaterials, in Massachusetts under M.G.L. c. 21C,
and M.G.L. c. 21£.
3(i)
310 CMR.33.00 reculations are adopted by the Departaent pursuant to the
authority eranted it under M.G.L. c. 111P. The reculations establish rules
and requireaents tor the disseaination ot inforaation related to toxic and
hazardous substances to the public.
4(a)
314 CMR 3.00 reculations are adopted by the Departaent pursuant to the
authority ,ranted it under M.G.L. c. 21, 15 27 and 43. The reculations
establish requireaents for dilc~arees ot pollutantl to surtace waters of
tbe C088onwealth. In addition to reculatine thele discharees, M.G.L. c.
- 21, I 43 allo require I the Departaent to reculate the outletl of luch
discharees and any treataent works assocJated with these discharees.
314 CMR 4.00 reculations are adopted by the Departaent pursuant to the
authority eranted it under M.G.L. c. 21, 15 27(S), 27(8), and 27(12). The
reculations establish Surface Water Quality Standards to aeet the coal ot
entrancine the quality and value ot the relources ot the Coamonwealth.
314 CMR S.OO reculations are adopted by the Departaent pursuant to the
authority eranted it under M.G.L. C. 21, 15 27 and 43. The reeulations
establish require.ents tor dischareel ot pollutantl to the eroundwaters ot
the Co..onwealth. In addition to reculatine these discharees, M.G.L. c.
21, 5 43 requires the Departaent to reculate the outlet for such
dilcharees and any treataent works aSlociated with these discharees to
alsure that thele waterl are protected for their biehest potential use.
31. CMR 8.00 reruJatlons are adopted by the Depart.ent purluant to the
authority cranted it under M.G.L. c. 21 If 27(S), 27(6), 27(12). The
reculat10nl eltablllh Groundwater QualJty Standards. These"ltandards con-
8ilt of croundwater classifications, which desienate and allien the ules
for which the various ,roundwaterl ot the Coaaonwealth Ihall be aaintained
and protected; water quality criteria nece81ary to lustain the delicnated
uses: and reculations necessary to achieve the delienated ules or aaintain
the existine Iroundwater quality.
314 CMR 7.00 reculations are adopted by the Departaent pursuant to the
authority eranted it under M.G.L. c. 21, 15 27 and 43. The reculations
establish a proeraa whereby sewer Iystems, extensions and connections are
-------
4(f)
4(1)
Sea)
'.
.3.
314 CMR 9.00 re~lations are adopted by the Departaent pursuant to the
authority aranted it under M.G.L. c. 21, I 27(12). The reaulat10ns
eltablish procedures, criteria, and Itandards for the unifora and coor-
dinated adainiltration of water quality certification of dredlinl and
dredled .aterial disposal and fillinl projects in the waters of the
couonweal th .
314 CMR 12.00 refulations as adopted by the Departaent pur.uant to the
authority aranted it under M.G.L. c. 21. II 27(8). 27(12) and 34. The
reaulations e.tabli.h reqireaents that insure the proper operaiton and
aaintenance of wastewater facilities and .ewer .ysteas.within the
Couonwedth.
441 CMR 21.00 reculations are adopted by the Departaent pur.uant to the
authority Iranted jt under M.G.L. c. 111P. The reaulation. establish
requlreaents for worker WRilht to Know".
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Activity
D~ede1ne
'0
.'
Groundwater capture/treatment
8ystea with effluent discharee
to 8urface water
. .
.'
. ~.. ..
TABLE I II
AcUv1ty/ARARs
Renlation
105 CMR 870.000 RR1eht to Know" .
I.ple.ented by DPH.
310 CMR 9.00 Adainistration of
Waterways Licences
310 CMR 10.00 Wetland Protection
310 CMR 30.00 Hazardous Waste
Reeulat10ns
310 CMR 33.00 Iaplaentation of M.G.L.
c. IIIP. E.ployee and Coaaunity
RRilht to Know"
314 CMR 3.00 Surtace'Water Discharee
per.it Prolraa
314 CMR 9.00 Certification for
dredlinl. dredlinl aaterial disposal
~d fi11inl in waters
441 CMR 21.00 RRieht to Know"
Iapleaented by DLI.
310 CMR 10.00 Wetlands protection
105 CMR 670.000 RRieht to Know"
Iapleaented by DPH.
310 CMR 6.00 Aabient Air Quality
Standards tor the Coaaonwealth of
lIa..achusetts
310 CMR 7.00 Air Pollution Control
310 CMR 30.00 Hazardous Waste
ReaulaUons
310 CMR 33.00 I.pleaentation of
M.G.L. c. 111P. Eaployee and Community
RRieht to know"
314 CMR 3.00 Surface Water Discharle
Per.it Pro~all
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.,
Groundwater discharie to Public
Owned Treatment Works (POTW)
Groundwater capture/treatment
'Yltea with effluent di.charie
to the cround
-'
.2.
314 CMR 4.00 Surface Water Di8charie
Quality Standards
314 CMR 7.00 Sewer Extension and
Connection Perait Procraa
314 CMR 12.00 Operation and '
Maintenance and Pre-treataent
Standards for Waite Water. Treataent
Works and Indirect Discharies
441 CMR 21.00 "RIiht to Know"
Iapleaented by DLI
314 CMR 3.00 Surface Water Di8charie
Perait Proiraa
314 CMR 4.00 Surface Water QualIty
Standards
314 CMR 7.00 Sewer Sy.tea ExtensIon
and ConnectIon Perait Procraa
105 CMR 670.000 "RIiht to Know"
Iapleaented by DPH
310 CMR 10.00 Wetlands Protection
310 CMR 6.00 A8bIent Air Quality
Standard for the Coaaonwealth ot
Massachusetts
310 CMR 7.00 AIr Pollution Control
310 CMR 27.00 Underiround Source
Protection
310 CMR 30.00 Hazardous Waate .
ReculaUons
310 CMR 33.00 IapIeaentatlon of
M.G.L. c. I11F. Eaployee and
Coaaunity "RIiht to Know"
314 CMR 5.00 Groundwater Dlscharie
Perait Proiram
314 CMR 6.00 Groundwater Quality
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~-
.3.
--
Incineration
Dechlorination
Containment
314 CMR 12.00 Operation and
Maintenance and Pre-treatment
Standards for Waste Water. Treatment
Works and Indirect Discharle
441 CMR 21.00 -Rilht to Know"
I.ple.ented by DLI
105 CMR 870.000 -Rilht ot Know"
I.ple.ented by DPR
310 CMR 8.00 Aabient Air Quality
Standards for the Co..onwealth of
Massachusetts
310 CMR 7.00 Air Pollution Control
310 CMR 30.00 Hazardous Waste
RelUIations
310 CMR 33.00 I.ple.entation of
M.G.L. c. 111P. Eaployee and
Co..unity -Rilht to Know"
441 CMR 21.00 -Rilht to Know"
I.pleaented by DLI
105 CMR 670.000 -Rilht to Know"
I.plemented by DPR
310 CMR 6.00 Ambient Air Quality
-Standard for the Commonwealth of
"8sachusetts
310 CMR 7.00 Air Pollution Control
310 CMR 30.00 Hazardous Waste
RelUlations
310 CMR 33.00 I.pIe.entation of
M.G.L. c. I11F. Eaployee and
Coaaunity -Rilht to Know"
441 CMR 21.00 -Rilht to Know"
I.ple.ented by DLI
105 CMR 670.000 -Rilht to Know"
I.plemented by DPR
-------
" 4 .
310 CMR 30.00 Hazardous Waste
ReeulaUons
310 CMR 33.00 I.pl.entation ot M.G.L.
c. I11P Eaployee and Coaaunity "Rieht
to Know"
441 CMR 21.00 "Rieht to Know"
I.ple.ented by DLI
Excavation/Ott-site Disposal
105 CMR 870.000 "Rieht to Know"
I.ple.ented by DPH
310 CtR 7.00 Air Pollution Control
310 CMR 10.00 Wetlands Protection
310 CMR 30.00 Hazardous Waste
ReeulaUonl
310 CMR 33.00 I.ple.entation ot
M.G.L. c. I11P E.ployee and Co..unity
"Rieht to Know"
441 CMR 21.00 "Rieht to Know"
I.ple.ented by DLI
.,
. ~.
-------
TABtE IV
More Strincent State Require.ents
for the ReSolve Site
This list is not an exclusive list
State,Reau1reaent
Standard, Require.ent, Guideline
Criteria. and Limitation'
1. Ait Quality Control
(a)310 CMR 7.00 Air Pollution Control
310 CMR 7.01
Establishes lUidelines for levels
of air pollution.
2. Wetland
(a)310 CMR 10.00 Wetland
310 CMR 10.54(4)
"
Requires any work on the bank of a
water body, not i.pair: the physical
stability of the bank; the water
carryinc capacity of the bank; the
,round water and lurface water quali-
ty; and the capacity of the bank to
provide breedinl habitat, escape
cover and food for filherie..
(b)310 CMR 10.~~(4)
Prohibits over ~ooo .quare feet of
10s. (dredle, fill, etc.) of bor-
derinl vecetated wetland, and
requires at least 1:1 replication of
any lost area within two 1T0wini
sealon..
/
(C)310 CMR 10.~6
Requires any work within ,land under
water bodie. or waterways (ponds and
Itrea..), to not i.pair: the water
carryinl capacity of any defined
channel; the ,round and lurface water
quality; and the capacity of the land
to provide breedinl habitat, escape
cover and food for fisheries.
(4)310 CMR 10.57(4)
Requires .co.pensatory Itorale" to be
provided tor any work that will cause
an increase in the horizontal extent
and level of flood water. at peak
flow. .
(e)310 CMR 10.57
Establishes the standards tor a
Variance tro. any ot the standards
contained in 310 CMR 10.54 - 10.57.
Par the project to quality for a
Variance: there .uat be no reaso-
nable conditions or alternatives that
would a110w the project to proceed in
co.pliance with the relulations;
'.
. .
, .
-'
-------
(e)310 CMR 10.S7 (Cont.)
3. Water Supply
(a)310 CMR 22.00 Drinkin2 Water
(b)310 CMR 27.00 UnderlTond Water
Source Protection
4. Hazardous Waste
(a)310 CMR 30.00 Hazardous Waste
310 CMR 30.131
(b)310 CMR 30.820 Landtills
310 CNR 30.822
310 CMR 30.623, 824
310 CMR 30.628
310 CMR 30.829
(c)310 CMR 30.830 SDecia~ Reau~reaentl
310 CMR 30.830(5)
(d)310 CMR 30.840 Waste Piles
310 CMR 30.846
(e)310 CMR 30.690 Tank Systems
310 CMR 30.696
310 CMR 30.698
310 CMR 30.697(1) and (2)
~
.. 2 .
aitieatine measures (such as full
replication of all iapaired wetland
areas) be included in the project to
contribute to the protection of the
interest of the Act; and the work
aust be necessary.to accomodatean
overridine public interest.
Departaentls Office of Research and
Standards Drinkine Water Guidelines
for 10 orcanic co.pounds; MA Maximu.
Contaainant Level for Sodiua.
Classification Proeraa.
Waste with PCBs above 50 pp. is relU-
lated as hazardous waste.
Must have double liner with leak
detection syste./collection (no
exemptions).
Requires demonstration of waste/liner
compatability and .onitorinl and
.inspection.
No exceptions.
PAHs.
Provision also for
Disposal of liquids in landtills are
prohJbJted.
Disposal of Containers of hazardous
Waste in other Containters (e.I., lab
packs) i8 prohibited.
Includes provisions for PAHs as an
acutely bazardous waste.
Minor differences corre8pondine to
tank desfen requirements.
General pertor.ance Itandard only.
State relUlations include polyaroaatic
-------
.,
,
~.
. I
~. Water Pollution Control
(a)314 CMR 3.00 Surface Water
Di.charEe per.it ProEra.
314 CMR 3.16 (2) and (3)
(b)314 CMR 4.00 Surface Water
9uality Standard.'
314 CMR 4.02
314 CMR 4.03 (4) A.1.
314 CMR 4.04
(c)314 CMR S.OO Groundwater
DlscharEe Permit ProEra.
314 CMR &.10
(d)314 CMR 6.00 Groundwater
Quality Standards
314 CMR 6.06
(e)314 CMR 7.00 Sewer System
Extension and Connection
Permit PrOEram
(4) A.2
.3.
Incorporates Standards fro. 4.02
Require. additional Standards
Miniaua Water Quality Criteria
Antidelradation Proviaions
No aiailar Pederal proer...
water classification.
Ground-
MCL. Health Advisories .used as
Standards. Por cheaciala with no such
atandard. acceptable levels will be
r1ak based.
Min18um Groundwater Qualtiy Criteria.
-------
,
, ~.
APPENDIX B
State Evaluatlon and Concurrence Memorandum
-------
APPENDIX C
Data Base - Flgures and Tables
-------
FIGURES
"Figure ~
Title
C-l
Site Location
C-2
original Site Conditions
and Remedial Action Plan
C-4
Total Volatile Organic Concentrations
in the Overburden Aquife~
Total Volatile Organic
Concentrations in the Bedrock Aquifer
C-3
C-5
C-6
PCBs in Sediments (ppm)
TVO Contamination in On-site
Soils: 50 ppm
C-7
TVO Contamination in On-site
Soils: 10 ppm
C-9
PCB Cqntamination in On-site
Soils "": 50 ppm
PCB Contamination in On-site
Soils: 10 ppm
" C-8
C-IO
Groundwater Eievation Contours
(November, 1985 Data)
C-ll
Groundwater Elevation Contours
(July, 1986 Data)
C-13
TVO Concentrations: Overburden
Aquifer
TVO Concentrations: Bedrock
Aquifer
C-12
C-15
On-site Incineration Alternative
Sensitivity Analysis
Dechlorination Process
Flow Diagram
C-14
C-16
Dechlorination Alternative
Sensitivity Analysis
-------
FIGURES (cont'd)
Figure ~
Title
C-l7
Off-Site Incineration
Alternative Sensitivity Analysis
C-l8
General Flow Chart for
Groundwa ter Treatme nt
"
C-l9
Alternative ~!0l!-2A
Heated Influent Ai r St ripping.
Alternative MOM-2C
Activated Carbon
C-20
C-2l
Alternative MOM-4
Pretreatment and Disposal at a POTW
C-22
Proposed Site Layout
C-23
PCB contamination in On-Site soils:
2 5 ..p pm .
C-24
PCB Contamination in On-Site soils:
25 ppm. Cross Section A - A.I
-------
RESOLVE IHe. SITE
NORTH DARTHMOUTH. MASSACHUSETTS
REcoro OF DECISION
SEPTEMBER 1987
FIGURE C-1
SITE LOCATION
-------
'.
_t
..mn...-_--_..
"'''----1'1---
10.... ....._CIII-
.. "".IJI;AV.''''8BOIII..
.__....u8D --...-
Ma..""""""" ".,18mI
~...--
-.
""'_88i_'--
UV..------
-.""_UV,.'88i
. ..-...
: ~
-.
......--. 88i___10
r._~__-
..._m
-.
.""_88i_--.
____._01-
-....----
------...--
____pea.._.
-.
.""_88i_~--
..........-----
IKAv.""""" 8ft.... 8tIiU.
..-
-.
..------
____810""""
----
...-.
......,..
r-. .1
LAGOON
AREA
'~7
" -.....-
... . a::t.
. .
!. ". I.
j': i !..:'. ~,~ ~.. j;
I'. I. ';0'" _. ~.-~::. ".rt
... ,,~-:,-,.~. " W
. iii,' \..".,
t "'1 i , ,.., \ ~I.,." ~~
.r . . . '..' I L- -c.
~1" ..' '. \\ /.. .-g'i"
. .\.. ~:
" .
:; J ~~~~~ f'.
...1 ,,~~- :'~;..c.....
i~; . "'~' ..-::-~~ j~; 'J''''';
.' .~"-.' '\
I . ,0.'
it
COOLING
POND
~
J
~
..".."",
~.r. :::
. ......,.
------_1___.
- I. "-. _.. &8 --.-.
_. .... ..,.,.. UlI- - IfI8IU ...
--.nn.._.__-
,... --... R-. - .11_.
......en - . .u.a . ...,
"
~ Aiiil'
---
p
;t
.
..
',\
\~.
.\
'\
. ~!:=~.
"
F.~URE C-2
-------
j
---: --
.
CI
a:::
~
~t
.1
i:
~!
-.
~I
01
Z
ND
I
~~
--
--
ND
/
/
/
/
/
SITE
.---
OUTWASH AQUifER MAY ,.83
OUTWASH AQU"." JAil. . A""'L '..4
.
8"
", ,., )
'-
8"
RESOLVE SITE
Danmouth, Massachusetts
Record of Decision
September 1987
FIGURE C-3
TOT AL VOLATILE ORGANICS
CONCENTRATION IN THE OVERBURDEN
AQUIFER
-------
. I
"00 _,/1
J
----
'00-'.000 .,/f
~
~
';
.
i
&
- -
..
o
Z
SITE
\
\ \0.000.00.0.
\ \ 100-5000
\ \
\.,.\
\ \.
\ ,
\ \
\ "
~
----
'"
\
\
I
I :
I
lu
, /
V
00 4/1
J/
I .
..., .
"
,
\
JOOO~
I
1
I
.
o
.
\
\
\
\
o -r/'
,
I
I
J
I
I
- ./
-- -- .,.-."
----
~~
-..-
..--
.
II"
8EDROCIC AQUIFER ..~y - , ..3
.
--- ..""OCIC AOU"." JAil. . AH'L fI'.
.11 "
RESOLVE SITE
Dartmouth. Massachusetts
Record of DecIsion
September 1987
FIGURE -4
TOTAL VOLATILE ORGANIC&
CONCENTRATION IN THE BEDROCK
AQUIFER
.. ....
-------
--
0- ( 1
J
---
102.7
102.0
60'
C-19
C.'0 -6.1 I
o f::~O l'
283'
107 6t!' <'.0 .
_.~
62 ~1?<"0 /
_C.'1 I \. ~ /
. . 22 C~':~ //
1 1.3,.. '- ii-L
M'':.23 /, ~T" 1- ~10'
t:-::'~~" (. " C'/ ;t'J-;' ~
<', " :[!.<1 \
C.'~/ .~ / 1 .
~~ 2 /@>.~<'t;!~r .10
- ~,~~ ~: / ~','3 ~j :..
- I ~ / c1 e-<10
~:..:.2 0-0 I~::.. R.t.,. to ......lIno . 2.7 <1.0
oonduct.d 10/...
'/.'1 >50_~
,~ < 50 ..... PCB
SITE
-
-
o
Z
Ical.: 1:lnc" 1 13.3 f...
RESOLVE SITE
Dartmouth, Massachusetts
Record of Decision
September 1987
FIGURE C-S
PCBs IN SEDIMENT
- -
. ,,' .
~. ..
..:'- '"
-------
'.'
I .
~.
II
~I
r
!
~Ii
II
vi
~I
4.
II
JI
Ii
II
II
I
.. ,~:I
'8,
ji
. 15
. i,-..
:1
,.
II
~
--
.. ..
..
..
.. ..
..
..
.. ..
.. ..
. ~
- ..-
.. ..
.. .. ..
..
.. ..
.. .. ..
.. " .. ..
..
.. .. .. ..
.. ..
..
..
..
II
II
I.
~:
II
~I
...
i:.
II
..
.. ..
RESOLVE SITE
Dartmouth, Massachusens
Record 01 Decision
September 1987
FIGURE C-6
TVO CONTAMINATION IN
-------
. .'
.
II
II
"
.
II
..
.
II
..
. .
58-
.
-. - LDCA~-
8ICLQIR) AIIEAIIHOW'M) con_T1ON
lIMA TBI nMH 10 Pftl DEI'IH IS 5HCMII II
aFOOT tn'EIWALS.
CJ ,..INTIRVALI con-tm
C .. WlEflYALI con-TED' .
. .. IfI'EfNALI con-TED
..
..
:.
il
I.
.r I.
II
"
"
II
.. .
.. ..
.. ..
.. .. ..
..
.. .
.. .
.. .
.. .. .
..
..
.. ..
.. ..
..
.. .
..
..
..
..
..
.. ..
..
~-
.. ..
.. ..
-- ~
RESOLVE SITE
Dartmouth. Massachusetts
Record o' Decision
Sa lember 1987
FIGURE C-7
TVO CONTAMINAnON IN
ON. SITE SOILS: 10 PPII
-------
fl'
I.
. II ..
WETLAND ..
. ---
.
II
. JI
~.
II
).
s,
I.
II
, . ,.
.0
.;
I
--'--'--
.
.. .
.. .. ..
..
.. ..
.. .. ..
.. " .. ..
..
.. .. .. ..
...
..
..
..
..
.
..
.. ..
.. ..
..
.. ..
Ii
~I
iI
;..
II
.. ..
..
..
RESOLVE SITE
Danmoulh. MUSIIChu18l1s
Record of Decision
Sep'8mber 1987
FIGURE C-8
PCB CONTAMINATION IN ON-SITE
SOILS: 50 PP"
'"'""-
-
-------
!
I
I
-\ ~i . .
I
:1
I'
il
I.
!
r
€.
I'
:1
.1
...
I,
~.
:1
I
. . III
.!
'0
!
11'
II
I.
~
!!
:,1
.
...
...
...
...
.
...
.
...
.
. ...
... ...
...
...
...
.
... ...
... ... .
...
... ...
...
...
... ...
... ...
... ...
,....- ~
- - --
...
...
...
...
I.
I
RESOLVE SITE
Oattmouth. Ual8Cllul8ft8
Record of DecIsIon
Sepl8mber 1987
FIGURE C-t
PCB CONTAMINATION IN ON-SITE
SOILS: 10 PPM
.'
-------
- _._- ._- -- - --.. ..
./.
.8la.L .
f'
I
.
I
Ii
J.
~.
II
!.
J
II
Ii
I
!1J
~
f:.
'I
It
. .
..... ~o1ITIII1U\IA1IDII CCINTCUI
- - MDJKTID.....-TIIIILIVATIOHCXJNYQIM
..
..
...
...
..
...
...
.. ..
..
...
...
,.
~~:~~... ....,{
'.""::~:.~;'.'\ .1.'
\\ /'
,.'~:~':~:,.
81&...-'"088 ~':.
. 8Ia.'\. 01
e,' .. ..
-.,. ..,.
,.' "
,. ,.
...
... ..
... ...
... ...
..
... ... ... ...
...
..
...
.. I
... ...
....
..
RESOLVE SITE
D8I1mOU1h. .............
R8CIOI'd of DecIsIon
Sepl8mber 1987
FIGURE C-10
ROUNDWATER ELEVATION CONTOUR~
(NOVEMBER 1985 DATA)
r--
~
-
--
-.-... - -_. ---
-.------
-------
.wu.L .
,
I
!I
I
.,
I~'t
,I
11
I
.
I
.
.~ I
I~
ii
..
;~ .
.~ I
I .
1.,1
Ii
ig'
-.
I
.
...
...
...
...
... ... ...
...
... ...
... .wu.L I.
... .wn.L K
,
'I
I
i.
-,
'I
...
... ...
,.
,.
III
I::
Ii i
._LL ~
. fI(JJ. I'S
RESOLVE SITE
Da/1ll1OU1h. M8s18ChuHIII
Aeoont of DecIsIon
Sapl8mb8t' 1987
--
.
-
--
~
.. . --.--
-- .,. -. ..
- .._a_' ".-".'-
. .
--_.......-
..,...-... -
FIGURE C-11
GROUNDWATER ELEVATION CONTOURS
(JULY 1988 DATA)
-------
'.
j
I
I
,
:,
J
I~
11,/
II
'.
I
!
,
,
.
!J
II
11.1
I. I
:;
.1
:i,
III,
II
Q
I!:
.,
I
.
., .
J.
I
ii
~.
~,
II
,
.IIb.L .
,
1/,
. ,
8-...' ,-
"
..
, .
I
Q
. 4f .
Q.
a:
.
. .
.
;.
.-..: ! ~
.,:::::-~_......~ ~~; ! ..
"". ,
....!~.
i i
..sb ~ ...
..... . .'1
.
..
..
.. .
LECEND
.
II!I'IOC. WILL LOCU-
.
OVlII8UIOI" WILL LOC.t-
.
~I_tl. LOCU-
TOTAL VOLA Tll!: ORGANICS
CONCENTRATIONS
.."0
~W.-,
o 1 . 10 PPM
. AfEJ 10-$0 PPM
.-.
>$0 PPM
..... APPROXIMATE AREA
OF DETECTABLE lEVelS
IIb.L 'w
..WlLL II
~-
.
--~
WILL Poo
. WILL '"
.
RESOL VE SITE
DlI1mou". Mal8Chuuaa
ReaIRI 01 DecIsIon
S.pa.mbet' 1987
,
,.
.
FIGURE C-12
TVO CONCENTRAnONS:
-------
,
-..---..-.
;..
.II
I'
I-I
Jj
.WlLL .
'~ :
I
,II
"
J
. I
I 'I
I'
,It
I!
I
~
I.
!~ I
I!
..
'..
I.
;.
:( '0
LJj
I; II
I~
,'"''
,I
I
. .
" I
, I
(I
~
"..
!I
I
tl
9
. i:
W, '
II
~-
-~
ICLL PM
".UL n
RESOLVE SITE
DlI1moulh. M8SS8dIUI81t8
Record 01 [)ecIsIon
September 1987
.
, I
,; I
: I
,: I
..... APPROXIMATE AREA
OF DETECT ABLE LEVELS
II(LL I.
. triLL .1
.
FIGURE C-13
TVO CONCENTRATIONS:
-------
'.
ttf!
o.!!!
0-
o
1;0
w-
ao
-=.
LC
~~
t-:5
.
.
.
.
I
.
.
.
.
.
.
.
.
!
Clean Up level
< 500 ppm PCB
o
10
35
30
25
20
15
10
5
RESOLVE SITE
Dartmouth. Massachusetts
Recrrrt of Decision
~~t ber 1987
SENSITIVITY ANALYSIS
ONSfTE INCINERAnON .-LTERNA11VE
.
.
.
.
.
.
.
.
:
.
:
.
Clean Up Level
c 50 ppm PCB
.
.
.
.
Clean Up level
.c 200 ppm PCIt
.
';. :
. .
.
.
.
.
.
:
.
.
.
.
.
.
.
.
.
.
.
.
:
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. .
. .
. .
Clean lip level E
c 350 ppm PCB E
. .
. .
. .
. .
. .
. .
. .
. .
: .
30
o
(Thou.and.)
VOlUME OF mEATED SOILS
ONSnE INCINc:tAnON
-
ON-SITE
50
Clean Up Level
c 20 ppm PCB
.
.
.
.
.
.
:
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
:
. .
. .
:
.
.
.
:
.
.
.
Cubic Yards
i.. -
.
.
.
.
:
.
.
Clean Up level
< l0PfJ!OPCB
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
:
.
.
.
.
.
:
.
.
.
.
.
.
.
.
:
.
.
.
.
.
.
.
.
.
. .
.
.
:
.
:
.
.
.
.
.
.
70
FIGURE C-14
INCINERATION ALTERNATivE
-------
Makeup
Water
Contamln
Soli
Water Condensor '
... ...
Vapor .. ..
~
, .
. .
ated..... Mix ..... React ..... Decant .... First I.... Second I..
..... ..... -JIll"" ..... Wash .... Wash I ,.....
I ...
--.
.....
...
...
-.--
Reagent ....
Heater ...
Clean
son
I
, I
'.
. .
RESOLVE SITE
Dartmouth. Massachusetts
Record 01 Decision
September 1987
FIGURE C-15
DECHLORINATION PROCESS
-------
tf!
Oal
u=
t8
w
,-
00
8:
8.0
~~
1)=
..-
::
'I
RESOLVE SITE
Dartmouth. Massachusetts
Record o' Decision
September 1987
"
. SENSITIVITY ANALYSIS
20
II
II
87
II
85
8..
83
82
11
80
.
I
7
.
5
.. :
.
.
.1 :
.
.
2 :
Clean Up level
8
< 500 ppm PCB
o
80
.
.
.
, .
.
.
.
:
.
Clean Up level
c 350 f.IPR' PCB
.
:
.
.
:
.
.
ONSIIE OECHlORINAtl~N AlTERNAtlVE
.
.
.
.
:
Clean Up level
c 200 ppm PCD
:
.
.
.
:
.
.
:
:
.
:
:
.
.
::
.10
(lhoulandl)
WlULtE OF mEATED SOILS
D OECHlORINAnON
.
.
.
.
.
.
.
.
.
.
.
.
:
.
Clean ~ level
< 50 ppm PCB
.
:
.
.
.
.
:
.
.
.
.
.
.
.
.
.
.
.
.
.
:
.
:
.
.
.
.
50
.
.
.
.
.
.
.
.
.
:
.
. '
.
.
Clean lip level
c 20ppmPCB '
.
.
.
.
.
.
.
:
:
.
.
.
.
.
.
.
.
.
.
.
.
:
.
.
:
.
.
.
:
.
.
.
:
.
.
.
.
Cubic Yards
"
Clean Up level
c 10PP!"PC,B
:
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
:
.
.
.
.
.
.
.
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:
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:
.
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.
.
.
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:
.
.
.
.
.
.
.
.
.
70
FIGURE C-16
DECHLORINATION ALTERNATIVE
-------
- I
t;f!
o.!!
u-
o
to
w-
ao
~(ft
LC
~~
0:=
t-:s
.
.
Clean Up level
: < 200 ppm PCB
.
Clean Up level :
.
: < 350 ppm PCB:
. .
20 Clea~ Up L8V8I: :
. .
csooppmPCB i' i
o
10
210
240
220
200
180
110
1..0
120
lOG
80
80
40
SENSITIVITY ANALYSIS
OFFSfTE INCINERAflON ~T£RNAT1VE
.
.
.
.
.
.
.
.
.
.
.
: '.~
.
Clean Up Level
c 50 PPT PCB
.
.
.
:
.
.
.
. .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Clean Up level
c 20 ppm PCB
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
:
.
.
.
:
.
.
.
.
.
.
.
.
.
.
.
.
30
50
Cubic Yards
D
(Thou.and.)
\IOUJLtE OF mEAnD SOIlS
OFFSII£ DISPOSAl.
--
.
.
:
.
.
.
:
Clean Up level
< 10ppmPCB
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
:
.
.
.
.
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:
.
.
.
.
.
:
.
:
.
.
.
. -
.
.
.
.
70
RESOLVE SITE
Dartmouth. Massachusetts
Record 0' Decision
Se tember 1987
FIGURE C-17
OFF-SITE INCINERATION ALTERNATIVE
SENSITIVITY ANALYSIS
-------
Raw
Flow
Removal of Oils
and Floatables
Metal
Precipitation
Removal of
Organics
Oil Disposal
Sludge
Concentration
Sidestreams
Treatment and
Dis osal
Metal Sludge
Disposal
RESOLVE SITE
Dartmouth. Massachusell~
Record of Decision
Sept. 9r 1987
Effluent
. Returned 10
Groundwater
Aquifer
Effluent
PolishilJg
..
Effluent
Discharged 10
Surface Water
FIGURE C-18
GENERAL FLOW CHART FOR
-------
'.
8:
I ...
.
,
::J
Il
"
I
eo
..
..
'i
»
.
I~
~t ..n ,lIurr...o ft "
...
.o.[nl"'" 5 i
.. :5
... CA'Al"lC ~ ~:: ~
26 9 IURNEII ot ....
u. 11 .. ... ....
.... u .,. ::Jz "
~ ,pM - ... "u S
» ..
. f!it i
" III
~ .
eo
III
.
eo
p..,
. .
»
.
eo
..
..
p."
PlA'" "'III
10osn"puw
SfA'1OII p.,
':
p."
Alii "","" R
pRf HfAUII'''...
IANO fllUII I'''''
IIenl: IIC"YAno CARIOt!.. pROVIOtD
fOR IfRfAM OISCHARIE ONlY.
r-DRA'"
l~'~(
LJ(j''''1O
DRAIN' AlIA
,-,
..
..
~ .
:.'j.
IUJl'Clf
... --r-~ I~~i~
'UJOH orca", -loJ~-U
p." MO SlOnAl( ,AN- ,..,. 'u-1f
,..
1l000(lll "p,
'OIllOl/"".."rll
DI.CtlAAlr
..
"
_.
. .
RESOLVE SITE
OAR T MoUnt. MASSAClIUSETTS
RECOR)OF OECISON
SEPTEMBER 1987
ALTERNATIVE MOM-2A
HEATED INFLUENT AIR STRIPPING
-------
"
. I I~
II
..
" ft
.. ."
. U
If
r
I
'
.
...
..
I P-I.
.
..
.-
"
, r"..
CQ-~.
OIl""
,MIl
,.,
f JlIL\U"
,.... II:
..
! II ..
,un" nlrp,"o 5 J '"
,o*(n".p) "C:"VAno « - ~ .. ..
uW ,
CAli 80ft ...
... ~~ ~1 ~
u" "u
a -W o!! :5
iJ .11< "0 ..
4
p.,.
POlI- l N'
u'n 51 011 IIOE Pl."'"
_110 '''1fII _nil
'UA"'ICIN) 100"'"
. PUMP
"""0ft
po'
<9J
~~= :..r:=:r""1
'0
fOUAlIlAfIClN
, roIWI!
'Mil ,..
Cn'l
P.M
PJI
....
~
,.....
cr TP. t
I.."
o
'lIOII CAMIllI 'MIa!
""* lOT JON -,
WADI~ I ~
BlOWfIlCn".
SlUDtE
-:t~~illi=u
tlUIIIf OfCAI" po'. ~
MIl ~'01lMr --
'Mil ,-.
fIIUII CIIIIICM '0
'OP W 110.0111(11
fII(SIt CARlON
"0"".( ,...
Pt.....
."fUl
,oc-
'"UCII
P-.I
'PEN' CAlltOft
1T000MlE '''"II
RESOLVE SITE
DARTMOUTtt, MASSACHUSETTS
J£eopr' "'4= DECISION
SEP' ER 1987
ALTERNATIVE MOM- 2C
ACTIVATED CARBON
-------
EXTRACTION
W-c:LJ..S
~""""',.....,"""""""""""'...."""""""""
~ """"""""""""',....,"""~
.. ..
~ OFF GAS TREATMENT ~
.. '
.. ..
~ . ~
~ CHEMICAL ADOmoN NEW CARBON ~
.. ..
.. . ..
~ I ~
~ ! ~
.. j ..
.. i ..
.. { ..
1 ; ~>~
~ ! ~
~ I ~
~ !. ~
~ 11111 ,,: ~
.. ..
.. ..
.. ..
.. ..
~ CARBON FOR ' ~
.~ ~~roN ~
, ..
, ..
.. ..
, ~
, ..
.. ..
, ..
.. ..
, ..
, ..
, ..
, ..
~ AIR ~
~ STRIPPERS ~
, ..
, '
, '
, ..
..~. ..
.. ..
.. ..
.. ..
.. ..
.. ..
, ..
.. ..
.. ..
.. ..
.. ..
.. ..
~ AIR ~
; a.ovr~ Fa:!CE :
~ MAIN ~
.. ..
.. / ..
.. ..
.. ..
.. ..
~ NEW ~
: PUMP ~
~ STATION ~
.. ..
~"""""~""""""""""""""""""""""",.................., ~
.. ,........"........"...,~
I
ONSITE FACILITY
TOPOTW
RESOLVE SITE
DARTMOUTH,MASSACHUSETTS
RECORD OF DECISION
SEPTEMBER 1987
FIGURE C-21
ALTERNATIVE MOM-4
PRETREATMENT AND DISPOSAL
AT POTW
. .'. :",,0..:.,
-------
, '1;
., ;
....
."
..
..
RESOLVE SITE
Dartmouth. Massachusetts
Record of Decision
September 1987
..
..
.. ..
..
...
...
..
..
. - - -
- ...
... ...
FIGURE C-2.
-------
- - -- ---.-
I
.
.
r J
-I
...
...
.. ...
.. .. ... ...
.. " ... ...
...
... ... ...
...
..
..
...
...
...
... ..
...
..
...
..
1'"""'10.-
1
--.
qy
RESOLVE SITE
Dartmouth. MasS8Chu18na
RecoId of DecIsion
~lemb8r 1987
FIGURE C-23
PCB CONYAIIINATION IN ON-SITE
SOILS: 25 PPII
-------
F9C::E
SB-U 8B-25W 88-25E
SB-25 N
QAOU
A
; .
'3-
"-
.t-
'0-
u-
..-
'7-
..-- -L
u- .1
. u-
. 13-
"-
81-
Z
o '0-
j: u-
c .
> 7'-
U 77-
...
U 7'-
7'-
7.-
73-
71-
,,-
70-
..-
..-
'7-
..-
.8-
..-
"-
..
..
..
...
,
,
RESOL VI SITE
D8r1moufI. MaS8Chus.1Is
R8O:IId of DedaIon
Stpl8mber 1987
..
,..
..
,
..
..
,
,
,
P'IATURATED
, ZONE
---
PROPOSED LMTS
(FecAVA1u.
..-21
ACE
8B-32
88-27
18-28
-------- --
.3L.- -
i
--
",."
58-37
F9I:E
N'PAOX&lAnE
LOWGUJC)WA1ER
---
E1£VATION
-1-
;
~
A'
-13
-12
-II
- 10
-II
-II
- 11
- II
-IS
..., I.
CXJPICUT RIIIEA - 13
-12
-II
Noll:
V.rt1c81 Set..
Exaggrqld 7X
fiGURE C-2.
PCB CONT AIUNA TlON IN ON-SITE
SOilS: 25 PPII
CROSS-SECTION . A-A'
-10
-F'
-FI
-FF
-18
-,.
-F.
-'3
-71
-rt
-70
-II
-'1
..11
-II
-II
-I.
-------
TABLES
Table No.
Title
C-l
.Historical Groundwater
Contaminant Plume Data
C-2
Summary of Risk Assessment
Results for Human Exposure to Re-Solve
Site Contaminants (Present Site Use)
C-3
Summary of Risk Assessment
Results for Human Exposure to Re-Solve
Site Contaminants (Future Site ~se)
C-4
Comparison of Concentrations of Indicator
Che~icals in On-site Groundwater To Drinking
Water Standards or Proposed Values
C-5
Preliminary Remedial Technology Screening
C-6
Summary of Comparison Screening
Source Control
Summary of Comparison Screening
Management of Migration
C-7
C-B
Summary of Source Control
Alternative screening
C-9
Summary of Management of
Migration Alternative Screening
C-10
Concentration Ranges and
Frequency of Volatile Compounds
in the Re-Solve Site Groundwater
C-ll
Design Criteria for Groundwater
Treatment Systems
C-13
Capital Cost for Dechlorination
of 25,500 c.y. of PCB Contaminated
Soils, and Sediments
Operation and Maintenance Cost and Present
Worth Cost for Dechlorination of 25,500 c.y.
of PCB Contaminated Soils and Sediments
C-12
C-14
Capital Cost for Incineration of 25,500 c.y
of PCB Contaminated Soils and Sediments
C-15
Operation and Maintenance Cost and Present
Worth Cost for Incineration of 25,500 c.y.
of PCB Contaminated Soils and Sediments
," . ~. '. > '.' .
-------
~
. TABLES (cont'd)
Table ~
Title
C-l6
Capital Cost for Alternative MOM-2C :
Precipitation/Air Stripping/Filtration/
Carbon Adsorption
C-l7
Operation and Maintenance Cost and Present
Worth Cost for Alternative MOM-2C :
Precipitation/Air Stripping/Filtration/Carbon
Adsorption
Calculation of Soil PCB Cleanup Levels for
the Re-Solve Site.
C-18
""'.
-------
4.
"
TABLE C-1
HISTORICAL GROUNDWATER CONTAMINANT
PLUME DATA
...
Ob8r-
vat Oft t:t.l Tl'u.- Tl'ichlol'Oeth 18ne ~~hy1... Chloride
_I a Vo1.U . 01' tea 't8tl'8dl1ol'oeth 1- 1-2-dichloroeth8n8 Vinyl Chloride Toluen.
n .1 .5 'J II 15 I) .. 15 I) It 15 n II 85 n It 15 I) .. 15
.
A
g. .1.U2.!IOO + + + + + + '.500 + + + + " .0" + + tl.OOO + +
Ie 85.510 + + 1.100 ". + + + + 16 .'" U.OOO
Of tt.JU 50.020 J!IO 210 2.201 1.100 J.OOO JOO 5.'" 1.500 16.000
.. U.Ol0 J'J .011 11.'10 ',000 2,501 2.600 2.800 1 201 26,000 '."0
OIl 1.00J 2.'" 11 tJ 11 2 21 n' 1.100 5SO 15,000
Ell 106 10 11 "
'" 82.281 U."1 11.000 U.OOO 11.000 11.000 15,000 2 ~'too 2S, 000 JOO no ISO
FC 111.'02 222.000 218. 'J'JO 18.000 1.'00 JlO 81,"0 15,000 50,000 II '.001 1..0.. 16 ,000 ',800, ',000
G l,tSJ IOt.OOO 81.110 no 12.0" '1.00' 1',000 ',200 2.500 J5.000 J,OOO
.. 1.'5J 1.112 I.JOO no 2 u.
HS 1.101 J,1U no 1,500 '00 1.100 1.000
IS 611 ',nl J6 1."0 2'0 J) 1.100 2.100 '10 1,)00
.JII 11,220 ".000 U, 550 81.008 ','00 ','00 . 5.000 1.100 1,"0 61,000 J"OOO U,OOO
118 U1 151 51 n 1 HO J4 180 28 to
U 415 1.'J'J' 220 110 11 JlO tS 960 1 2'J
L 228 1Jt 51 10 1 , n 111 2. U 11 150
lIS 11
- 51 15
OIl 11 It
QII 1.200 '.050 1.221 nl ',201 '.'00 2,100
.
.. 11 2J 1
WI . . . 8 .
VJ 8 . . . .
tns . U,"I 221 . 61 . U.500 5. . 221 . '.510 UI n I,JtO
VIS . . . 8 J .
tHD . 11 n . 2 1 . J J 8 11 n .
1155 . tt . 5 . 5 , 8 5 II . 202 21 5
-------
TABLE C-1
(conl'd)
HISTORICAL GROUNDWATER
PLUME DATA'
CONTAMINANT
Ob8,r-
vat on t:tal 'rran8-
..... Volatl . Orgaalca !8t~.cbloroethyl8ft. I-J~lchlor08than. 'rrlcbloroethylana 91111f'1 OIlod. "-thrlana OIlorl. 'l'o1-
n .. 8' U .. .5 n I. 85 n .. 85 n .. .5 n .. 85 n .. 15
0N-01 . . '18 . . . . 510 . . . .
ON-OI . . nl . . . . UO . . . .
0N-09S . . . . . . . . . .
OIf-l0S . . . . . . . . . .
OIf-l1S . . . . . . . . . . 10
58-0.S . . 205,"1 . . 1,001 . . U,OOO . . 2J,OOO . . 1,000 13,000
58-09S . . t5 . . 15 . . 21 . . 5) . .
s~1tS . . 11,11' . . 5,." . . . ,. 1,tOO . . 105
'i
S~J5S . . 105,008 . . . . 1,100 . . 21,000 . .
S~)OS . . 51,061 . . J,101 . . 1',000 . . .,100 . . 1,.00 16,000
. ..811 cUd aot ..18t at ti- of 88.,1189-
-------
HISTORICAL
TABLE C-1
(conl'd)
GROUNDWATER
PLUME . DATA
CO NT AU'NANT
Qbat~- 'l'1'8I1a-
vat on T:tel
Welh VoiaU . o~ tea 'ht~achlo~08t 1811. 1-2-dichloroethane I OIlortde NIt hn. 0110 ride '1'01_.
U It IS U It 15 IJ It 15 IJ It 15 It 15 U It 15 n ,. 15
.. l,tOO + + + + '00 + + + + 100 + +
a 2,IU s,tu 11 2,'00 2,200 150 360 5tO 110
U U
PC ',110 ',UI ',12' 1,200 2,200 U '00 2,000 ",000 2,.00 10 ]S 1'0 , 71
IJ8 1,'10 511 ..1 2J n n u u , no nl u no ..
JS 1,101 10,000 I,UO 1,100 1,000 210 1,100 J,101 t,tOO 2,JOO 21,000
- 51 J5
os 7t t5
PS 11 , 11
QC '15 101 111 1 5 1 l' to 110 J, 100 :JZ
SIC 50 U
WJO . .. . .. . 5 . 5 . 5
"to . It 11 . 2 1 . 1 J . It "I)
1150 . '1 .. . . 11 18 . 5 11 . 10 15 5
1160 . 2,ltO . UO "I . 2J . 2,000 2,100 1
0If-0'" . . . . . . . . . .
011-090 . . . . . . . . . .
011-10" . . . . . . . . . .
011-100 . . . . . . . . . .
011-11" . . . . . . . . . .
011- 110 . . . . . . . . .
5&-250 . . 50. . . 1.1 . . 210 . . 210 . . Z.Z
5&-210 . . U,'20 . . ',100 . . ',100 . . 26,000 . . '00
. ...11 did DOt '..tat at ti.. of a88pltng.
-------
TABU C-2
StOOWl! OF RISK ASSESSMENT RESULTS FOR BUKAN EXPOSURE
TO IESOLVE SITE CONTAMINANTS
(Present Site-Use)
Present Site Use
Exposure Pathway
Total Exeess
Upper Bound
Lifetime Caneer
llisk
Hazard Index for
Non-careinolenie Effeets
Direet eontaet with on-site soils
Averale ease
Plausible maximum case
-8 - <1
6xl0 Sb
. 4x10- <1
- 8
SxlO-Sb <1
8xlO- <1
.Direet contaet with off-site soils
Average ease
Plausible maximum case
Inhalation of VOCsa released from
on-81 te soils
Average case
Plausible maximum case
,'!.
-9
9x10 6b
1xl0-
NE
NE
Inhalation of partieulate matter
released from on-site soils
Average case
Plausible maximum ease
Dermal contact with surface water
Average ease .
Plausible maximum case
8xlO-ll <1
7xIO-8 <1
-9 <1
9xlO 6b
lxlO- <1
Inhalation of VOCs released from
surfaee water
Average ease
Plausible maximum case
-7
2xl0 6b
Sx10-
<1
<1
Inaestion of fish
Average case
Plausible aaximum case
7X10-:~b(eel consumption)~
axl0 (eel conumption)
NE
NE
NE . not estimated.
BvoC . volatile oraanic compound
bNote that exeess eaneer risks areater than lxl0-6 may be unaeceptable.
cFor ingestion of fish species other than eels, total excess lifetime caneer risks
. would range from 7xl0-6 for the average case to 4xl0~4 fOT the plausible maximum
case.
-------
TABLE C-3
StRIKART or RISK ASSESSKErn' RESULTS POR IIUMAN UPOSURE
TO RESOLVE SITE CONTAKDWn'S
(Future Site Use)
Future Site Use
Exposure Pathway
Total Excess
Upper Bound
Lifetime Cancer
Risk
Hazard Index for
Effects
Inaestion of on-site aroundwater 4xlO-3b 4c
Average case
Plausible maximum case 5xlO-lb 410c
Direct contact with soils -7
Average case 1x10 2b <1
Plausible maximum case .,.." 3xlO- 12c
Inhalation of VOCsa released from
on-si te soils 3xlO-5b
Averaae case NE
Plausible maximum case 3xlO-4b NE
Inhalation of particulate matter
released from on-site soils -7
Average case 3xlO 5b <1
Plausible maximum case 2xlO- <1
NE . not estimated.
a VOC . volatile oraanic compound.
b Not. that excesl cancer risks Ireater than lxlO-6 ..y be unacceptable.
C These scenarios may pose unacceptable health risks. .
. .
, ';
-------
TABIB c-4
CD&RISJf ~ ~ ~ DIDrAT
-------
'DIU C-S
mBL1HINARf BIHIJW. 'DDHIlX:r SDI!HIH;
~;~, Technologies
Applicable for Ca1sideraticn
Applicabili ty/Calllll!nts
t
-------
.
~-I~' Tedmo1ogies
~c:able for Ca1sideraticn
kface ~
~
Dikes cd BeJ:ms
Levees and FloodwalJs
Bench Temsces and Drainage
Bench
a.mels am Vater.oays
O1Jtes and D:M1pipes
Seepage Basins and Di tc:hes
Bet81ticn Basins
Cofferdlas
Gradirv
""taticn
T.6JU C-5
(CcntinJed)
mm.ooNAIa' RIII!mAL 'DDHIJJ:!' s:mamr;
ApplicabW ty/Q:ams1ts
Pcssible ~
cmtrOlll8SlJre far soils
and SlldiDlmts
11--'-1 ~, Tedmo1ogies
TedlU.c:ally Fesible
kface ~
Applicable to reduce further Cappq
infila:adm of preclpitaticn
t~ w1l developsi
Possible short-teeD c:anttol
II!!8SUI'e
51 te not located in flood
hazard zme
Not applicable, no very
steIP slopes
Possible t~rary III!BSUI'e
~ cm-si te CXI1Structicn
cd ea=avaticn
Not applicable, no steep
slopes
Possible to use to reroute
surface water to protect
cap and to mdmp trated
gm,niwater
p"quires 1arp anBS of land,
1arp IIIIU1ts of smI and
silt mt . problIIII
Hay.be used ~ clemJp
or :in cmjmcticn vi th
SlldiDlmt t8JY8l
Used vi th c:appiqr, lmI-
~ an:! I!ICI:2M1tic:n
Used vi th c:appiqr, l.sxI-
fili.iqr ani eccavatic:n
. -
D1bs cd Be1ms (ttaparUY)
ChImels am Vaterways (teqmaIy)
Seepage Basins and D1 tc:hes
Cofferdam
~
-------
P-'fi!ll' Teclmlogies
~cable for CcI1Sideraticn
nBt Omtrol
~
!lccavati~
Injectia1lF.xttacticn Vel.ls
IImDbilizaticn Teclmlogies
Clalmt mi Silicate Based
PbcatiwslSelf...c...ntaticn
'Jhm:m:)p]a.stics
'DI-nn rosetslPol)'lDl!rlzaticn
&Jrface Ha.cro-ex:apsuJticn
GmltiIw
Aban.balts
Vi trlficatia1
TAIU C-5
(Catt1DJed)
!mJHINARr BIHI1IAL 'DDHIm! ~
Applicabili ty/C'.aml!!1ts
Used \Nn ~ scurc:e
IIIIterlals
PeovaJ. of sed1m8tts 8Ii
soils, diffiaJlt below
water table
Used to extract arcmdwater
£ran bsirodc. (deep wlls)
and overtmden
"'"
OJesticmble .,- vith
organics IIIItnx due to
new Ta2 ~ proc:Idure
Hay incn8se subsequent
optiCl1S. ScIII! solvents
and sreases c:aJ.a as;ml t
to softm. Salle =dizers
can cause explasicm.
Inc:cIqBtable wastes, such
8S oqanics, reduce chaJas
of aood resu1 ts
..
Not . well dev8lope:I
tec:mology
Soil 8Ii 8tiDmt
st8bi1i-tian
Not ~~t tr81D1tt mi
incr8ses 8ID.I1t of IIIIter:ial
to be disposed of
Infm:lllltiCl1l.V8n.h'~
thrql sm: Pt~cd
~hI' Tedmlogies
TectmcaUy Feasible
DBt Omtrol (tlqm8ry)
P.8IDval
ISccavatian
InjectiCl1lExtracticn Yells
IJmd)il1zaticn TreaCll!nt
FbaticnlCtmentatian
'1betDcp]a.stics
Gr:cIutilw
-------
~i.' Tedmolcgies
. AoPlic:able for Cmsideratim
Art1f1da1 Gmni ~
In-Si tu BladzV
~tiCl1 Technc10gies
Precipi tatic:alCallgulatiCl1l
~""Il.tim
s.i1m!ntatiCl1lC1arlfic:adCl1l
Gravi ty 'Ihida!nina
c.ntrifuptim
Filtmtim
DIwa~ I.apn
'D'mDal De8t8rlzw UUts
Classific:atim
-'
TA1U C-5
. (CcI1tizu!d)
.
BBJKINAK!' ~.&, mBIJ.(X;f ~
AoPlicabi11 tY/OmII!nts
P-4ill' T~es
Tedmc:ally FEllSib1e
Not .. . ~-,t Artif1da1 Gmni ~
tratll81t, bit a:JU1.d be use! (ttqmary)
.. lEt of 8ICC8Vatim
Not . w1J. ci8Yelop8i
tec:molqry
Hay be useful in tratDll!nt
for r8IaV8l of inorpnics
cd -- oils, r8IUires
ctisposal of s11Ifge
May be.'\JSI!d far ~ of
Sldimmts 8IIi in c:mjmctiCl\
vi th precip1 tatim or
bi~cal tnatmmt. 011/
_ter separators can be use:!
for I'8IIJV8l of t!XtIaCtables,
~ disposal of sJ.qe
Sep8rates suspenitd and
c:01loidal soUds, ussi for
industrial h8zardous vaste
ttatmmt
ShIip 8IIi ~
water J8f nqui%e
further tratllEnt
Not sui table for w1atile
taldcs or ana vi th biab
_ter: table
HIy require tadsrim
cxntrols, II) aile wd ts
8dst
HlybeU9ldu~
tnatmmt to rtIIICJV8 large
debris &aD 1II!di\ll to. be
trated m:i c:ancmuate
waste, soils, or !JI!dim!nts
Precip1 tatic:alCoqulatic:nl
Flo::/"II1 II tim
Swli~tatiCl1lClarificatiCl1l
Gravi ty 'Ihic:icln1qf
c.ntrln.tim
Filuatim .
'J'-r-' Dewa~ UUts
rt II~ fi c:adm
-------
~i:ll Tedm1cgies
Applicable for Cansideratim
Cartm Adsorptim
p.-h1e Bed Treatment
PcMIered A1:.tivated Carbcn
Iat~
}
Resin Adsorptim
AirStrippq
Stesm Strlppq
D1Sti1laticm
!vaporatim
Dissolved Air FlotatiCll
. ,
TAIU ~5
(Q:ntUud)
mPL1HINABr BFJH1W. 'DI:JHUXar S1&NJH;
Applic:abW tylO:llants
Hay be used in £om of
liquid or vapor phase
cantactor (the Iatter in
canj\.l1CtiCll with air
strippq)
Not applicable '--tee of
l1mi ted life of c:arbCI1,
l1Jcelihood of ~ mi
desorptim, and fractures
in bedrodt DBY result in
grotniwater ~
tratlDlnt
Hay be ,a lllethod of
~ter tratlDlnt
May be \med for rfIIIMl of
imrpnics, but czUyafter
ptetraCDent to reduc:e
caantraticns of oils am
orpnics
Not applicable vi th very
heteropl~ \lUtes
am be used to strip
Y01atiles £ran \lUtes
Hay be used to strip
so1.lbl. orpnics 8S wll
8S Y01atiles frail WlStes
Not applicable to r8IIOV8l of
px:ly'definsf feai Str8lllS;
c:r.n:mtmticm of
canUllllimnts are loll '
TedlUque for dewaterirv
SIOils and wi.-tts; va:
rIIII:7Val
Hay be used to strip
Y01ati1eorpnics 1I'hile
~ eacttat:table oily
wastes
Ja--fi:l' Tedm1cgies
TldlUcally Feasible
Qarban Adsorpticm
PcMi8red k.tivat8d r.bcn
Iat~
Resin AdsorptiCll
AirStrlppq
Stesm Stri~
Bvapomticm
-------
~i ~ 1 Tec:hnolqJies
Applicable for Ccnsideradcn
Freeze Cryst'~ 11 . -- ticn
Salwnt Pxttacticn
Soil ~
Coalesc:ers
Hec:h8nic:al Aeraticn
r.v.rse OsnDSis
I
tn ttafil traticn
Electrod1alysis .
DetalCificaticn Tratml!nt
Aerobic Bi~ticn
NBerobic Biodegradaticn
TABLE C-5
(Ccn tinJed)
~ RI!JI!DW, 'IBJIWXaf s:1&NJN;
Applicabili ty/Cammts
tbtawe1l-deYeloped
ted'r1D1qy for bIzardcut
vastes
p..-4i~1 Tedm10gies
Tedltically FtllSible
tbt a ted'r1D1qy to be used Salwnt Exaacticn
1Ihm there are amy ~
Hsy be USBi for ~
exttac:tab1es £ran soils
Hay be used to t8II:M!
extraCtable ~
Hay be -O$ed as ~te
tratllllnt to strip
wlatiles £ran the soil
Soil Flushins
Co&1esc:ers
Hed8dc:al Aeraticn
Applicable if ~ by. B8verse 0sImis
a process to nm:J\/e oils
n larpr acl.ecules, such
as ulttafiltraticn
Hay be used to t8II:M! SCIII!
of the higher 1II018t"111A"
weight c:mtllldnlnts
tbt applicable because waste
does not have high
cxn:81traticm of salts and
iemc species
Hay be applicable b-t-
pmw!ft effectiw em amt
c:mt8ldr81ts. ItIIst notable
ea::epticn is
tettachloroethyl81e
Hay be applicable,
~i.lly in c:mjux:ticn
vi th aerobic tratllllnt
tn. trafil traticn
Detaxificaticn Ttatml!nt
Aerobic Biodegradaticn
-------
TAIU C-5
(Ca1tinJed)
lmIHINARr BIHDW. ~ ~
P.emedia1 Technologies P-'li:ll 1 TednUogies
Applicable for Ccmideraticm Applicabili ty/Q:mzmts Tednically Feasible
~tq ~ be applicable to soils ~tirv
8rIi sediaEnts cmtainiqr
exuactables mi PC!s
Land Treatml!ntlSpray Irrlpticm Not 8pplicable to tre8tml!nt
of volatiles; c:n-si te land
ana limited; cmnNater
hiah in IIUCh of the area
P.eciroJlatitX1 Systems Effective in tre8~ soils Beclrt:ulaticm Systems
arxi ~ter esp--;:II11y
in c:aIIbinatitX1 vith 8II!r'Obic
biodegradatitX1
QJZyIIII tic Degrada ticm Not . wll developed
technology for hazardous
wastes
Dechlorinaticm pa reduc:titX1. prOY81, DIc:hJ..orlJw.ticm (pilot plants
IIIObile \I1i ts avanJlh1e avai1_b1e)
tn travioletlOza1a ticm Effective in ~ PC!s; tntravioletlOza1atitX1
prinBrily an off-site
tre8tD1!nt
OIcidatitX1 Potmtially toxic byproduc:ts
could wrs&n smniwater
cmtam1natitX1
01I!mic:a1 Reducticm Not . wll developed
tecmology for 'Uge with
aoils 8nd graniwater
Neuttalizaticm HIIy be eppUc:ab1e to N81tmlizaticn
neu"'" 1 i "'-e efflumts £ran
lata1s precipi taticn process
O11.omlysislOilorlnolysis Not damtrated for
hIzardcm wastes
~1ysis/Electto1ysis Not a wll developed
tratment tec:molqry
-------
~;;11 Tec}n)lqfies
~cab1e for CcnsideratiCll
1bm::DBl DesttUCtiCll
Cb-Si te St~
Vaste Pile
Stonge Vault
Stonp Bins
Stonge Bags
TankIDtuD Storage
&Jrface 1qx:u1dment
Cb-Si te Disposal
lOA Landfill
ClIp Vell IDjectiCll
tms Disdmp
Off-Si te Disposal
lOA Unifill
~.
TA1U C-S'
(cm~iIud)
mBL1HINAR!' BIKDIAL 1B]HI.(X;f s:mamc
~cabi1i ty/O:mll!nts
MIy be \.SId to destray
mpnic:s cd Pas in 80ils
8Dd 8iimmtS
tky be applicable as
temporary stomp for
nJIIM!d soils 8d I811m!nts
~ial TedI1o]qies
Tednic:ally Feasible
'DED8l D8auctiCll
(b.Si te Storage
Vaste Pile (teIIp)rary)
Hay be applicable as sbort- Storage Vault (tl!lllpOIal)')
term stOI3ge prior to
~
tbt applicable for 1£p
quanti ties of waste
tbt applicable for 1arse
quanti ties of waste
Applicable for smrt-tetm
storage of grtmdwater
~ off-site
transportatiCll
1q)1.-rttatiCll diffic:ult
vi th high \later table
CantainDent OVE time
not-assured
Hay be sui table for
treated \later
TankIDtuD Storage (temporary)
&Jrface 1qx:u1dment
cn-Si te Disposal
lOA LmW.ll .
Not Applicable in
. New Fzw1and
NIm Di.scharp
Off-5i te Disposal
lOA Unifill
. : .,:
. , .
-------
11--';21 Tedmologies
Applicable for O:I1Sider.&ticm
'l'naamt, Storap, Disposal
('rSD)Facl1itiei
IbUdP8l Vast_ter
~amt Facility
Resourt:e Rec:ove1y Facl1i ty
, .'
'fAII.B C-5
(Catt:il1Jed )
mP1JHINARf RHmAL 'J:IIJIIIa;r mamc
Applic:abili tY/OmDents
May be epp1ic:able for .
1aqe IUIIber ,0£ wstes
Hay riquin prea:.amt
Usually not for hazmbm
wste
p--H.1 Tedmologies
Tedmically Feasible
'l'SD Paclli ties
ibUdpal Vastwater
-------
- ---
'.
R8&1ial Altematlw
M» AcUm
~1 M» AcUm
(vi th f8lclqr)
«b-Si te TnlBt8ent
~2 'IbemIl Destructfm
TAIIB ~
SIIIARr (I OII'ARIDf DaRIN: 9110 cnmo.
Total Project
Costs
Total Present Vocth
$1,640,an
$31,341,an
Project
hpl....tatim Period
htnnmtal ant N»Uc:
llealth Cmsideraticng
.:11
,:r)yrs
1. EUllfnate actess to em-
t_inated soil soorce areas
by fme'" .
2. Allows cmtfmed release
of cmtalinants to the
gromdwater, prolaws
period of pooc ~tel'
3. Restricts future use of the
site in vtdn~ ty of soil
.:: soorce areas.
5yrs
1. as aIxwe
4. (hilp'!ded future use of sf te
5. EUldnates risk frCII spills
associated vi th trcnport
of cmtaainated sons
6. Hitlgates potential for
offst te Idgmtlm of sons
am cmtadnated gmnIwatel'
after treatllent Is CXIIpleted
1. ft)tentlal release of air
"ssims ci.Ie to treat8l'!1t
process. Other potential re-
leases lnc.1tde eJCI3Vatim, I.e.,
chit gEneCatlm, \IOJatilizatlm
of c:mtauJnants, am soil eroslm
resultfrw In surface vater
iIIpiIC ts to \letbnls
o
«bIparism Pb.tbWS
'Dds altematfw has
been retained for de-
tailed deveJq.!nt t~
pmvtde a IBsls for
CDpIrism to other
alternatives as stl-
p1lated in R:P.
Reaedial Alternatives
~2 am ~ \oWe re-
tained foe detailed
deve1qwnt since they
provide envfrmnental
beneftts for the treat-
8eI1t of cmta8inated
soil. Also, they have
high anr..dnants reo-
-------
'.
Re.dfal Alternative
~3 Soil Vashbv
. ,1
s::-4 Dechlodnatfm
~5 CaIpostlrw
TAIU C-6
SIIIARf (W 0IftRISIf ~ SlID mmu.
Total Project
Costs
'lbtal PresEnt Vorth
$12,10),00)
$17,038,(0)
$18,850,(0)
Project.
JJt}l...-atatfm Period
: 4yrs
3yrs
10 yrs
&NI1'OI'IIB1ta1 ... l\j)Uc
Health Cmsfderatfms
1. 4,5,6,7 as ~2
8. Generatlm of reslcb11s
after trEStIB1t reIJIlr1rv
handlh~ or disposal
1. 4,5,6,7 as ~2
8~ GeI1eratlm of resfcbtls
after trESt8ent reIJIlrirv
hand1i~ or disposal
1. 4,5,6,1 a1d 8 as ~2
9. Potential release of ail'
ea1ss1cn9 We to treat8ent
process Is hifter than
other msl te tl1!BtJlnt
alternatives
10. RaJtl rirv 1aqe spJCe
11. Pedoramc.e Is affectaJ by
\leiJther
~sm Piolt.
R8aedlal AI temative
~3 vas screened wt
, ~LC:P it does not
have high nmval
efficiency as ~2 ...
~. 'Ihe oost effec-
tlW!l1eSS of disposal
a1d trEStabilityof its
reslWals are
fJJeStlmab1e too.
~ sfmld be selectaJ
before the others, if
treatabilt ty stuly data
for both soil ant resl-
ciBls stlstantiates 81
adelpate performnce.
~5 vas screened wt
t--~ I t requires
large operatlrw spJCe,
a1d the perfomance 15
affectaJ by mId
-------
'.
TAlI. C-6
SIIIARf .. (DItAImIB SHBmC 9110 mmo.
Total Project Project FmhtDlmtal cnI N»1tc
Rsnedlal Alternative Costs 1q)1e11B1tat 1m Period Health Cmslderatlms OJIprlsm Plnlb~
Total Present Vorth
~ JJnmbillzatlm1 $15,600,(0) 2 yrs 1. 4,5,6,7 as ~2 ~ vas screened ~t
O1Ba1cal Fbcatim ::: beca1se of its Hili tEd
12. Vaste vohue lrri'eases after success vi th solvmts
treatJlmt reqdrl.. cdIi- , and IUs.
timal hal¥:tlq oc disposal
13. Uaited success vith solvmts
am KBs
In-sl tu TreatJEnt
g:,...7 cmtaiJ8!l1t1 $2,500,(0) llyrs 1. as ~1 RsIBIlal AI tematlves
In-si tu Bl~ 9;-1 and &;-8 \Be Ie-
degradatim 14. RfdIctioo ()[' elbdnatlm tained for: detailed
: of anta;dnants in soU developIEnt since they
soorce resu1tiJw in 81 provide env1 nnmtal
acce1eratim of grunlwater bmefl ts for the treat-
cl~ 00e to ndlctlm in IBIt of antalinated
leachlaw of cmtaainants soil vi th order of
to gmnIwater Egni tude casts less
than the others
15. HetallJqiorls of hazimbIs (9;-1 mly).
nature of soU soorce areas
vi dwt prnblEE associated
vi th excavatlm1reawal
~ cmtair8entl 'PI,an,an 15yrs 1. as ~1 1bIever', treatabUI tY
In-sl tu 5011 stutles are to be em-
ntSdrw 14. as ~1 cb:ted to smst81tlate
. .J the adefptte perfom-
4,5,8 as ~ 181CeS. 9;-1 am ~
are ~1ned after
15. as ~1 the preliainary screen-
1.. to incoqxK"ate de-
tailed anslderatim
,
-------
TAII.B C-6
9HIARf (IP ORARI9Jf SHBmC 9IRB mmo.
Total Project Project bhuwntal and rm1tc
ReEdlal Altenatfve OIsts J.pt.....tatim Period' Health Cmslderatlms OIIpuism Plntl....
Total PresEnt Vorth
fu-SI te Cmtair8l!l1t
'"
~9 ~ttm $2,900,00> J}yrs 1. as~1 ~9 vas screened oot
Omtructim as an IrdiviOOal in-
Period 8 tb1ths 16. Rab:tim or prevmttm ' depenlent trea bII!n~
of infiltratim into soil process '-;11- of
soorce arms resultirw in potential release of
gmnIYater cmtadnatim cmta81nants in the
future. Ibwever, It
17. Cant_nated soils vas anfldered as a
rulBinirv m-si te 8iIY CDIIpD!IIt of a camined
came future release of proCess.
cmtcainants
1&. Restricted use of the sf te
me to existEnCe of the
hazardws wstes
~10 1DAIr.rA IAntfill $4,9OO,an J}yrs 1. miI~l ~10 ViIS screened CJUt
OnItructim '--- it did not Eet
Period 12 tb1ths 8. "ires 1e&chate dlspasal SARA requfrenents.'
01" treat8ent
18. mil ~9
581""t TnBt8I!nt
~11 581l8Ent CWirw $2Q),an . J}yrs 1. Ilbdnates ac.cess to ~11 \lIS a.:1a::llled CJUt
OniItructim wetland ... lI118I!d '--- of potential
Period 6 Hmths trUutary areas by ~irw release of cmtalinants
in future.
2. as~1
3. mil 9;-1
-------
'.
TAIIE C-6
.
9HCARI CJP (lJltARl9lf S1I!IIfIN; 9UU mmo.
Total Project Project Fnvltuwental ani NJUc
ReEdlal Alternative Costs 1q)1...-.tatlm Perf~ Health Cmslderatlms (DpIrlsm PiRI",
Total PresEnt Vorth
11. as ~9
-
-
S:-12 SEIIl8entatim $tOO,an u.»lE8!11tattm 4. as~2 ~t2 vas mt an-
RaIIwal mI Period 4 tb'aths , stdered as an iRUvi-
Tn!at8!nt (addi ttmal tiJne 6. as~2 Ul ildepenlent
mly) treabaent proa!SS lot
1. as~2 8 CXIIpD!I\t of a CX8-'
bined process.
Off-Slte TnBt8!nt
. . ~13 IOAIr.D IAnlfill $21,an,an 18 Ib1ths 1. as~1 ~13 vas screened out
'-"-~ of the OIIY81t
1~ as ~2 lanI bJn regulatims.
19. PotEntial for pl......,
and safety problf8'J 00e
. . to extensive hinll1Jw
and transportatim
s;...14 Inctnerattm $213,~,(XX) 18 Ib1ths 1. as s;...1 s;...14 ... retained for
detailed developEnt
1. as ~2 since it provides ore
envinnElltal benefi t
19. as ~13 and fnstitut lmal
8Ca!ptance than an
20. High oost is cb! to the off-site lanIfill.
legal restdctims to lanI
-------
. TAlI. &-1
9IIfARf fI 0IeAImDf DIHmC IWfM)IJRft' flltJIUImI
Total Project Project FnvInnmtal and N»Uc
Ranedlal Alternative Costs JIlp1saentatlon Period , Health QJ1sJderatlons CaIpBrlsm Fir1ll1..
Total PresEnt Vorth
tb Action
.~
~
tlJl-l tb Action $910,00 ~yrs 1. Gninlvater vill cle8rq) 'Ibis alternative vas
in 17~ yrs as a result retained for detaf led
of natural pro'P&c;e; deVe1op1B'8t to provide .
a basis for aIIpIrlsm
2. Jnclmes Iml torilv to to other alternatives
detect off-sl te
-------
. I
. .
I.
'DIIB &-1
SHfARf fI OWAKl9lf SlHXUI: IWWBIIU' fI KIDtmOf
Total Project Project DMnnB'Ital cnI rmuc:
lBBIial Alternative OJsts ~lE8l!ntatjm Period Heal th Cmslderattms OIIpIrlsm rtmqs
Total Present Vorth
tlH-28 Predpi tatim! $S,m,an 10 yrs 2. as tlH-l 'Ibis alternative vas
Filtration/carbon .... scremed mt ~ aB-
Adsorptim 3. as tOI-l pldsim vi th tlH-2C
IIPMIIAI! of the low
5. as tDf-2A \OC I'EIIIJVal efficlE!l1C.'Y.
6. as tDf-2A
7. bJes mt effectively
.. " I1!IIDII'e \tt3
tlH-2C Predpitation/ $S,250,«Xn 10 yrs 2. as tlH-l 'Ibis alternative has
Air Str1~bwI as ilH-l been retained for de-
Filtration/carbon 3. tailed cIeve1q8ent
Msorptim IIPMII- j t provides
5. as tlH-2A 8OI'e envtl'U'lll!ntal
. benefit InI better
6. as tlH-2A gronhater .,ml ty
than the others.
.i tlH-2D Predpi tation/ $10,10),00) 10 yrs 2. as tDf-l 1his alternative has
Air Strl~tJwI been scremed mt by
. Biodegradation/ 3. as tlH-l CDIprlsm vi th tlH-2C
Filtration/carbon IIPMII.... it provides m
Ad!mptim 5. as tDf-2A atditimal envtr:m-
.. ...tal benefi t but
6. as tOI-2A teIfrl.res operatimal
:"1 iJM)lV8El1t cnI extra
costs.
:
-------
'.
TAIIE C-1
SIIIARf (Ir CJWARI9R DHHOO tWWBBfI' (Ir IfDA1'IOI
'lbtal Project Project fnvimwntal iDI I\j)Uc
RsIeIUal Alternative OJsts I8pleJlBltattm Period . Ileal th Cmstderattms a.pmsm F1rwJt~
Total Present Vorth
Off-Site Disposal -
'W'
tlH-3 lOA TID PaclUty $17,D),an 2yrs 6. as tlH-2A 'Ibis alternative has
.. screened oot be-
8. Offers a permnB1t solutim cause of htgh oosts and
to the gmnlwater em- less depEmabtlJ ty.
talinattm
9. Potenttal for releases and
safety prnblE116 me to eJC-
tenstve hintl1JW am
transportatim
10. Pel'lormnce am Up181B1t-
abUt ty depEnt m the
8vaHabtlhy and acceptance
. I. of TID faciltty
Off-Slte TnB....t
KJt-Jt Ifttrea....tI St,.,an 3yrs 6. as tlJf-2A 'Dds alternative has
I\8pbw to been IetabBI fO[' de-
Vastevatel' Treat8ent 8. Offers a peuw.ent tat led cIeve1.opEnt
Plant solutim to the granMatel' ~~ of its
cmta8tmtim effectiwness mI
practical! ty.
10. Pedonrma! iDI ~te.nt-
abUt ty ale depeDlent m the
availability am acceptance of
-------
tiBLE C-8
SUtOWlt OP SOURCE COR'1'JlOL AL'l'BIHATIVES SCUENING
Alternatives Eliminated
Detailed Development
Alternatives Retained
Alternatives Screened'
in this Section
Se-l No Action
Se-l No Action
On-Site Treatment
Se-2 Thermal DestructiOD
. Se-2 Thermal Destruction
Se-3 Soil Vashini
Se-3 Soi! Vashinr
Sc-4 Dechlorination
Se-4 Dechlorination
SC-s Composting
Se-s Compostini
Se-6 Immobilization!
Chemical Fixation
Se-6 Immobilization!
Chemical Pixation
In-Situ Treatment
'I
SC-7 In-Situ Bioderradation SC-7 In-Situ Biodeiradation
SC-7 In-Situ Soil Treatment*
5C-8 In-Situ 50i1 Flushini
SC-8 In-Situ Soil Flushing
On-Site Containment.
SC-9 Encapsulation
SC-9 Encapsulation
SC-l0 RCRA Landfill
SC-l0 RCRA!TSCA Landfill
Sediment Treatment
SC-11 Sediment Cappini
Se-12 Sediment Removal
and Trn taen t
Se-ll Sedillent Cappinr
SC-12 Sedillent Removal
and Trea tllen t
'Off-Site Treataent'
SC-13 RCRA Landfillinr
SC-13 RCRAITSCA LandfilliDi
Se-14 IDcineration
Se-14 Incineration includini
.edi.en t removal and uea tllen t
*Se-7 In-Situ Soils Treatment includes containment vith a slurry vall or sheet piliDi
folloved by in-situ biodeeradation and soil flushinr in a phased approach.
, '
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TABLE C-9
SUJQWtT or MANAGEMENT or MIGRATION AL'l'BBNA'l'IVES sc:u.:BNmG
o
Alternatives Screened
"OH-1 No Action
On-Site Treatment
..
"OH-2A Precipitation/
Heated Influent Air
Stripping/Filtration
"OH-2B Precipitation/
Filtration/Carbon
Adsorption
HOH-2C Precipitationl
Air Stripping/ Filtration/
Carbon Adsorption
HOM-2D Precipitation/Air
Stripping/Biodegradation/
Filtration/Carbon
Adsorption
Off-Site Disposal
HOH-3 RCRA TSD Facility
Off-Site Treatment
HOH-4 On-Site Pretreat.entl
Pumping to Vastewater
Treatment Plant
-.
Alternatives Eliminated
"OM-2B Precipitation/
Filtration/Carbon Adsorption
HOM-2D Precipitation/Air
Stripping/Biodegradation/
Filtration/Carbon
Adsorption
"OH-3 RCRA TSD Facility
Alternatives Retained
"OH-1 No Action, however
. retained a. part of SC-1 not
as a ..parate alternative
"OK-2A Precipitation/Seated
Influent Air Stripping/
Filtration
i:
MOM-2C Precipitation/Air
Stripping/Filtration/
Carbon Adsorption
"OH-4 On.Site Pretreatment/
Pumping to Vastewater
Tr.a taen t Plan t
. . '.,"-
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T~t.E C-10
.CONCENTRATION RANGES AND FREQUENCY OF
VOLATILE COMPOUNDS IN THE RESOLVE SITE GROUNDVATER
Volatile Compounds
Acetone
1,1-Dichloroethane
1,1-Dich~oroethylene
trans-1,2-Dichloroethylene
T.trachloro~thylene
Toluene
Total Xylenes
1, 1, 1-Trichloroethane
Trichloroethylene
Vinyl Chloride
Methylene Chloride
Ethylbenzene
Methyl ethyl ketone
He..dyl isobutyl ketone
Extractable Compounds
1,2,4-Trichlorobenzene
Polychlorinated biphenyls
Inorganic Compoundsc
Arsenic
Chromium
Cadmium
Iron
Magne51 um
Hanganese
Lead
Concentration Rangea
(ppb)
11-37,000
7-~,700
29-1,000
1-83,000
3-14,000
2.2-33,000
21-6,700
6-35,000
6-50,000
1-8,000
600-16,000
1-1,300
10-62,000
40-6,800
FreQuencyb
8/27
9/27
5/27
23/27
18/27
13/27
13/27
13/27
20/27
15/27
5/211
12/27
8/27
7/27
(PCBs)c
1-230
4-1,200
16/27
8/27
5-148
13-221
5-724
1,740-293,000
706-27,200
236-20,700
13-479
16/27
22/27
13/27
26/27
27/27
i6/27
18/27
~umber of samples in which contaminant was detected by the total number of
samples.
bData obtained from the Remedial Investigation Report by Camp Dresser &
McKee, February, 1987.
~ata obtained from the unfiltered samples.
-------
TABLE C-ll
DESIGN aITEaIA POIt GltOtJNDVATER TlBATKENT SYSTBKS
(Design based on 45 cpa flow plus 25% .idestreaa ~ir~ulation)
. --. _u ....
<> GENERAL DESIGN BASIS
I.
Operation 24 hr/day, 12 mo/year
Influent Flow ltate 45 Ipm (65t900 Ipd)
" II. UNIT PROCESSES
'.,
1. Equalization/Storage Tank
Number of Uni ts - 1
Influen t Flov S5 cpm
Equalization (vet volume) 2 hours
Storage (dry volume) 4 hours
Total Volume vith Freeboard 20,000 Cal
.. I 2. Oil Separa tor
Number of Uni ts 1 It
Influent Flov 55 Ipm
Max. Effluent 011 and Gr.ase 10 l1li/1
3. Solids Contact Clarifier
Number of Uni ts 1
Influent Flov SS gpm
Surface Loading !late 500 gpd/sf
(0.35 cpm/sf)
Net Settlinc Area 130 sf
Flocculation, Detention Time 15 minutes
Diueter 14 feet
4. Neutralization Tank
Number of Uni ts 1
Influut Flov 53 cpm
Detution Time 15 minutes
1..... Volume with Freeboard 1000 Cal
5. Air Strippers (GV-2A)
Number of Uni ts 2 (one opera tine , one
." standby)
" , Influent Design Flov 53 Ipm
Air to Vater Ratio (vol) 100 to 1
Blover Air Flov 750 cfm
Tover Diueter (minimum) 3 feet
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TABLE C-U (CONT'D)'
DESIGN CRITERIA paR GlOONDVATBIl TltBATHINT SYSTEMS
(Design based on 4S IP8 floy plUS 25% 8idestreaa circulation)
6.
Air Strippers (GV-2C)
Number of Towers
Influent Design Flow
Air to Vater Ratio (vol)
Blower Air Flow
Tower Diameter (minimum)
7.
Vapor Phase Activated Carbon
Number of Uni u
Inlet Air Flow
Carbon Quantity per Unit
8.
Activated Carbon (GV-2C)
Number of Uni ts
:'"
Influent Design Flow
Total EBCT/Unit
Contactor Dimensions
Carbon Load per Unit (min)
Fresh Carbon Storage Tank Capacity
Spent Carbon Storage Tank Capacity
9.
Activated Carbon Canister (GV-2A)
Number of Canisters
Influent Design Flow
Total EBCT/canister
Volume
Type of Filter
10.
Sand Pl1 ter
Number of Uni ts
Influent Desian Flow
Type of Pl1 ter
Surface Loading Rate
Pilter Area/Unit
(, ,",'
2 (one operatin~, one
8tandby)
53 ~pm "
150 to 1
1,100 cfm
4 feet
.2 (one ope~.tinc, one'
8tandby) ,
750 or 1100 cfm
10,000 lb.
t.
2 (one opera tin" one
standby)
53 gpm
60 minutes
7 ft. dia. x 12 ft. hirh
5000 lb.
10,000 lb.
10,000 lb.
2 (one opercting, one
standby)
10 ,pm
60 minutes
600 callons
Dovnflow
2 (one opera tin" one
8tandby)
53 cpm
Gravity, Downflow
2 Ipm/sp
-------
TABLE C-ll (CONT'D)
DESIGN CRITERIA FOR GIlOONDVATD DEATKEN'l' SYSTEMS
,(Desisn based on 45 spa floy plus 25% sidestreaa circulation)
"
11. Sludge Filter Press
,
,
Number of Uni ts 1
Capacity 10' CF
0 Cycles per day 1 "
Sludge at 40% Solids 750 lb/day
Sludle, Dry Solids 300 lb/day
12. Sludge Bolding Tank
" Numbe~ of Uni ts 1
Volume 3000 lallons
13. Reaction Tank (Polishing)
Number of Uni ts 1
" Influent Flow 10 Ipm
, 'j Detention Time .'.'. 15 minutes
i I
Volume with Freeboard 200 ,allons
,
14. Kicrofiltration Unit
,; Number of Uni ts 1
Influent Flow 10 gpm
Filter Flux 600 gpd/SF
Fil ter Area '24 SF
15. Effluent Storage Tank
Number of Uni ts 1
Volume 10,000 gallons
. ,
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TABLE C-12
CAPITAL COSTS POR DECHLORINATION
OP 25,000 C. T. OP PCB
CONTAMINATED SOILS AND SEDIMENTS
1) Excavation vith Sheet Piling $ 475,000
" 356,400
2) Operations Area
3) Treatment Process 3,654,000
"
"
4) Replacement of Soils 112,500
5) Loam 580,000
6) Seed 9,000
7) Moni toring 'Equ~pment' 50,000
, '
Subtotal $5,236,900
Pilot (l0%) 524,000
Engineering (15%) 786,000
Contingency (15%) 786,000
TOTAL $7,332,900
"
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TABLE C-13
OPIIATIOH AND MAIHTBMANCB AND PRBSBMT VOR'l'B COST
POR DICBLORpiATIOH OP 25,000 CY OP PCB
COM'1'AMINATBD SOILS AND SBDIMBHTS
.
1) Personnel
2) Pers~nal Protection Equipment
3) Realent
4) Vaste Disposal
5) Field Labor
6) Office Support
7) Puel Cos ts
8) Deprivation
9) Haintenance
10) 'travel
11) Side-Stream Treatmeat
$ 30,000
10,000
122,000
122,000
154,000
35,000
25,000
70,000
100,000
10,000
419,000
$1,097,000
Present Value (10%) for 2 years
$1,097,000 x 1.736 . $1,904,400
Total
$1,904,400 + $7,332,900 . $9,237,000
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TABLE C-14
CAPITAL COSTS rOR INCINERATION or
25, OOP Ct or PCB CONTAMINATED SOILS AND SEDIMENTS
piling
$ 475,000
356,400
6,875,000
112,500
580,000
9,000
50,000
$ 8,457,900
846,000
1,269,000
1,269,000
$11,841,900
1) Ex~avation with sheet
1) Operations Area
3) -Treatment Process
4) Replacement of Soils
5) Loam l'
6) Seed
7) Monitoring Equipment
Subtotal
Pilot (10%)
Engineering (15%)
Con t ingency..... (15%)
TOTAL
. >,' ,. '.,
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TABLE C-15
OPERATION AND MAINTENANCE AND PRESENT VORTS COST
POR INCINERATION OF 25,000 Ct OF PCB CONTAMINATED
SOILS AND SEDIKENTS
'. u
1) Equipment
2) Labor
3) Fuel
4) Electric! ty
5) Process Vater
6) Vastevater Disposal
7) Caustics
8) Oversized Debris Removal
9) Laboratory
TOTAL
Present Value (10%)
$2,950,000 x 1.736 . $5,121,000
$5,121,000 + $11,841,900 . $16,963,000
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$. 650,000
77-5,000
775,000
200,000
5,000
110,000
110,000
30,000
295,000
$2,950,000
.~ ....... . . .
-------
'fABLE C-16
CAPITAL COSTS POR
ALTERNATIVE HOH-2C PRECIPITATION AIR STRIPPING/
FILTRATION/CARBON-ADSORPTION
Alternative 2C
1) Collection System
2) Extraction/Recharge VeIls
3) Groundwater Storage Tank
4) Process Equipment
including groundwater treatment work,
sludge dewatering facility, carbon
system and pumps and piping for
the treatment facilities
5) Site Preparation
6) Site Vork
7) Electrical Vork
8) Instrumentation
9) Building
$ 175,000
340,000
315,000
1,830,000
55,000
285,000
94,000
66,000
300,000
Subtotal
3,460,000
Pilot Study (10%)
Engineering and Administration
Contingencies (15%)
(15%)
346,000
519,000
519,000
. ,
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Long-term Sampling and Maintenance
$1,571,720
TOTAL
$6,416,000
'. "-, 'I ...,".
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..
tABLE C-17
OPERATION AND MAINTENANCE COSTS
AND PRESENT VORTH COST POR ALTERNATIVE JlOM-2C
PUCIPATION/AIR STRIPPING/FILTRATION/CARBON ADSORPTION
Operation and Kaintenance
Alternative 2C
. c.
Personnel
Jlaintenance
$179,000
113,000 .
140,000
75,000
61,000
125,000
$693,000
Pover
Sample and Analyses
. Carbon and Analyses
Carbon Regeneration
.'0.
Present Vorth
~ect Costs for 10 years operation, at 10% interest
rate, PIA. 6.144
Alternative 2C - Precipitation/Air Stripping/
Filtration/Carbon Adsorption
$6,416,000 + ($693,000 x 6.144) . $10,674,000
,. .
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.
TABLE C-18
, ,
CALCULATION OF SOIL PCB CLEAN-UP LEVELS FOR THE
RESOLVE SITE
Soi I Concenrnr ions Exposure AssUliprions
Assocl.red wlrh Levels
Direct Conucr 01 flcess C8nCer .'st 5011 Incldenrll
IIlrh Solis (..It,) Conucr De... I Ingeulon Ingestion . Vllhl Torll lody
(De,... I end ..re Absorprlon ..re Absorpr I on 'er Telrs "elghr
IngeUlon) 10.4 10.5 10.6 10.7 (I/"ili t) F.ctor (..I"ilit) Flctor hlr Visited (tg)
'resenr Sire Use (Trespeillng),
Aven,. CIS. 20.000 2,000 200 20 1 0.01 20 0.35 10 5 30
"ausib'. H..i.u. C.s. 200 20 2 0.2 5 0.05 100 0.50 50 5 30
'.
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Furur. Sir. Us. (11I.denrl.,):
Aver... C'a.. 300 ]0 ] 0.3 1 0.01 20 0.35 100 70 70
:. . "ausibl. "I.'.u. C.I. 10 1.0 0.1 0.01 5 0.05 100 0.50 200 70 70
!
'CI porency lecror: 4.34 (../kg/d.y).1
.,
-------
P'.DfAL RBSI'aGIVDmSS SRMRr
, Re-Salve, Inc. ~ Site
IIIztb Da&,1 - .Jtb, -- .....a...... I la
m1A WCII:X "-i"JI_L Ho.: 14G-1L18
RDI XI ~ L a..~ Ho.: 243-m:1~1
PRI!:PARm RR
u.s. ~ m.,1--'I'I(~ AGDa
ICrIiI.U'l I
D.a'~'-&f, ~~ISJr.'I.m
.,'
PrepIred by tM RI!JI XI Pmject Te8 \Dier m1A ~il&.e8% Ho. 68~1-6939
o:iI5t' -- 1987
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'mB[B OF
-------
Part II.
mstE OF CXIfJ:DfIS
CCkntiluad)
~
ctIHms FR:M rormt'IALLY ms~IBIE PARrIES.....
. . . . . . . . . . . . . . . . 22
A.
Intrcduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
B.
IV.
PRP CaIments a1 the Public Health Evaluation...................... 23.
1.
Technical O...._rtt,s at the Public Health Evaluation.......... .23
Selectiat of Chemicals far Aeg--~~...................23
!t.mIan Health Risk Assessment:/Pot
Devel~.t of the Rs-Solve site............ ',.'.'."". .24
a.
b.
2.
~c::I)lt::llJY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
PCB
PRP O...._.,¥ts at the FS and Preferred Altmnative................. .36
1.
2.
3.
4.
5.
6.
7.
~isapplicaticn of ARARs......................................36
~icientia1 .tam Use.................. . . . . . . . . . . . . . . . . . . . . . . .38
I.r1st.i'blt,ia1aJ., a..iI-Luls....................................... 39
Potential Risks of Preferred Altmnative.....................40
1 ~ PCB Q-i'teJ:iat................................ . . . . . . . . . .41
Mi~icatiat of 1lPeJ:mnent1l ~es............. .'........ .42
Qzi)inin;J Source Q:).1t.ul and Manaqement of Migration
Altmnati'VeS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
8.
9.
10.
li.
12.
13.
14.
15.
~~ and Incx:Insistent SC:reenirq PI-ocess.................. 43
SOil EXcavation Volumes......................................44
Wetlanis Restoratiat.. . . .
Dechlorinatiat and ~inq Technoloqies.....................45
Ct:8't. Effec:t:.i'Vel'1eSS........................................... 47
c:a::.-ts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . '. . . . . . .47
...................................45
Disorganized and Q:I1tusinq Cost Infcmuation.................. 48
GI:t::a.Jrd. 'Wa"ter'....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
~ RJBI.IC ~............................................. .51
ATl'AaHNr A - CXIMJNI'IY REIATICH; AC'l'IVI'1'IES CXHX1CTED AT '!HE
RB-5C)I,VE sm................................................ S2
~.
'~
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Preface
-"
'!be u.s. Envira1menta1 Protectia1 }qercy (EPA) recently held a p.1blic
~-'1t period for interested parties to O"'..-ut at EPA's June, 1987 draft
Feasibility Study (~) and preferred altemative for the Re-SOlve site. 'the
,~ e.~;T1eS and evaluates varic:us q7ticnJ or ~b1 altematives for
ca.lh.~inq Cla'ltaminatim at the site. At the t.ima of the p.1blic v....1I!!/Ttt
period, EPA had annamced its preferred .&.-..::ro1y for the cleanup of the Re-S01ve
site.
''Ihe PJ%1X&8 of this respa1Siveness m_ry is to doo-nt EPA responses,
to the ~ and questicns raised dL1rin;J the public ~nt period. All of
the ~-'1ts ~"ized in this tW~ will be factored into EPA's final
decision of -the preferred alt.m:native for clear&.1p ot the Re-Solve site.
'!his respa)Siveness ~;nmMry is divided into the folla..dn:J sectia1S:
I.
Resca1siue.........", SUrrlMTV OYe%view - 'Ihis sectim briefly outlines the
IU-' ~ ~; ,,1 altematives as pt ~H1ted in EPA's dratt ~,
in::l\.Ktinq the ~erred alternative.
- II. BacJa::rramd a1 thrIftmitv Invclv-£t am CoI-!D1'TIS - 'lhis sectim
'provides a brief history of t'Y'llWlllnUty interests ani a:n:erns
. rega.rc::lin;J the Re-Solve site. .
III. ~TV Of ~nts Received DJrin:I the Public o...lauel1t Period and
EPA Rescouses to 'lhese a.......-J'Its - 'this sectiat SI~t"izes both
written and oral ~'1ts received ~ the public ~'1t period
am provides EPA ~es to these o....~. Part I SI-,.izes
public <:s ....- d:s and EPA respa1Sss, and Part II !I::I-l"izes ~'1ts
fraD potentiaJ.ly respcl}Sible parties (~) and EPA respa1Ses.
'1hese <> .....~'1ts are atganized by subject area.
IV. Rf:!rMinira ~,.,... - 'Ihis secti.a1 descri1::es 0CI1CemS that were net
. ~y addressed durinq the RI/PS. EPA needs to ~-s these
cxn::ems durinq the design and ~ementatia1 of the ~; ,,1
altamatiV8.
AM-A J...Ait A - 'Ihis atb..lMlIl:lut in::ludes a.list ot the t'Y'llWlllnUty
J:8laticnI activities CXI'1duct:8:i at the Re-Solve site durin) EPA's
r--r4i"1 site p1.~CIIII.
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2
I. ~ SDH\R{
-------
3
In ~-.&.cal, the 0 ....~'1ters (~t. the PRPs) SURX>rted the d10ice of the
dechlarinatia'\ and the gram-water treatment altemative but were CC1'1O!!Z'ned
about the byprcx1ucts and effectiveness of dechlorination, air emissions
resultin3 trail dechlorinaticn, and PCB mbility and oontaminatia'1 of the
aquifer as a result of flush.ing the grcun:Iwater.
PRPs c:x:mDe1'1ted that EPA iJa:xn1.a.:tly ~lied the SARA requirements for
'MARs, "AFPJ,icable and Relevant ani ~~iate Envu<:'lIIIt:Irt:al ani PUblic
Health PeJ1h ~a". ARARs are the Federal ani ~te envUWllllt:lttal ani
health standards that are used to devel~ the ~~iate level of clean.Jp at
SUpert'Unj sites. PRPs argued that the ARARs Used to devel~ the cleanup
standards tar the Re-Solve site shcW.d have been the RCRA closure standards
tar hazardcus 'waste larnfills or surface i~a, as ~ to the safe
DrinJcin; Water Act: standards ani other requirements. '!he PRPs also cli.sagreed
with EPA's decisia'1 to select cleanup standards that wculcl pexmit future
residm1tia1 use of the site. In additia'\, the PRPs raisec1 questims about
CXISt estimates, risks of the preferred alternative, ani the CD1Si.steR:y of
assuIIptia1S and methcdology used in the FS and the PUblic Health Evaluation.
-'
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4
I:r. ~ (If CDMm'l'Y ~ AND
-------
,. ".'., .
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5
III. ~ O/P CXIIEN1S R!ba1J!D [I]RIH; 'JBB roBUC CDImNr A!mCD AND EPA
R!SPCIE!S 'It) 'IBESB CXIIEN1S
'!his respollsiveness !l::l.DmA1"j' ack1resses both oral and written ~1'1ts
received by EPA cxn=emin;J the draft Feas:ibility Stu:1y and Preferred
Alternative [)ocI1ftIAY1t for the Re-Solve, Inc. SUperfund site. 'Ihe ~'1t
peria! was held fran JUne 11, 1987 to July 7, 1987 and then extended to July
31, 1987 at the request ot several CXIIIDel1ters. A p.1blic hearin;J was held at
Dart:mcuth Town Hall ca July 1, 1987 as an "+¥A't.urUty tor the p.1blic and other
interestEd parties to pl e s ~1 ,t oral (~_...~J1t.s to EPA. '1hese 0 ....- .ts are
reo:nda:! in a transcript: ot the heafinq which is available at the inf01:matica
repositories and at the EPA Reqica I oftice in Bcsta1, Massadu1setts. EPA
also received written ~ at the draft !S.
'!he written and oral ,:,> ....-.Its frcD the PJblic are SlDmA1'"j.zed and
orgcmized into the follOlli.rq six categaries: (A) ~;~1 alternative
preferences, (B) tedmi.cal cxn::ems regardin;J ra-iial alternatives, (C)
~trU.ty relatia'lS and PJblic participatiat, (D) ccsts and tundin;J i9(;lW"9,
(E) entOX'a!lDelIt, and (F) 1II;~1laneQ]S. O.'.'-its trcm potentially respcndb1e
parties are 0I"IJU1ized into the tollowinq bIa c:ater;Jar1es: (A) PRP <> .....A. its ca
the Public Health Evaluatica: and (B) PRP .:>-...-d:.s ca the PS and Preferred
Al~tive. EPA respcnses are provided fer eact1 (. ....-It, or set ot like
~.
Betare the start of the public ~'1t period, EPA i9fll'" a press release
and a fact sbeet descr:ibin;J its preferred altemative tar the Re-Solve site.
In ack1itica, EPA provided a ~;:nlm\;:l1"j' ot the preterred altemative in the Friday
JUne 19, 1987 editiat ot the New Bedford Standard Times. 'Ihe preferred
alteJ:native CXI'1Sists ot both a scuroe ~1tJ.~1 and ~'1t ot migratiat
0< ""I.:x1e1It. Specitic:ally, the preferred ...--Jy entails eccavatica ot PCB-
CXI1taminated soils and -.r1i-U, and t:reatDEnt in an ca-site mcbile
dechlor.inatia1 facility. In ad:ii.tiat, a:ntaminated grcund water will be
pmpwt and tmated with an air stri+Pinq \mit and CaJ:txn ~at to remove
volatile organic u"'I~ (VCCs).
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6
Part I.
MBLIC rted EPA' s cboice of decblorinatia'1 with gromd-water treatment as the
preferred alt.e1:native for the Re-Solve site. S8Yeral Q....~ (the Sierra
Club, WRDF) ncteQ that Reqia'1 I deserves 0....- dttia'1 in decidirg a'1 an
innc:Ivative technology. 'Ibe Sierra Club also SI~ the identificatia'1of
incineratia'1 as the backup q7tia'1. 0. ....- ats regartl1n;J the various
alternatives di!l:t.'''9sed in the Feasibility Study are ~~1'"j,zed below.
1.
SCUrce a...LLul
a.
a..u.'8:llt:
'1b8 Sierra Club noted that if the badoJp q7tia'1 of incineratia'1 has to be
used, the cboice of type of incinerator will be iDp:n:tant. 'Ib8 <> .....AI ater
noted that the Feasibility Study d88c::rib8 t:m:. methcds -rot:aJ:y Jeiln,
- infrared, an:l tluidizec1 bed - but does net icBttity EPA' s preferred
method or relate tD;t estimates to incineratia'1 method. '1be O.'.'~lter
stated that in vi&t f1 the fact that there may ):)e greater air quality
benefits and cost benefits ~iated with particular q7tiaw, EPA shcW.d.
provide mre detailed intomatia'1 to the plblic if it ~rs likely that
incineratia'1 will be used.
EPA ~:
Upa1 CXIIpletia'1 of the pilot-s:al8 stucly for d8chlorinatia'1, EPA will
di ~KUJ the ftISUlts at a PJblic infamatia'1 meet.iD:l to be held in
DartIID1th, MassadD.1sett.s. If the becJcup q7tia'1, incineratia'1, is
selected to treat the PCB-o:I1taminatec:1 soils an:1 -"li1MWJts, EPA will
provide additiCX1al intomat.ia1 a'1 ead1 method of incineratia'1 presented
in the Feasibility Study.
"
2.
.-or...
L of IIigrat:.icn
a.
t\ ....-.L:
",
ow (~....- iter (F.ccYa) referred to "th8 teamical an:1 ecxu::w.c advantages
of biological treatment" aver the pl'~ cazi:x:1n polish:in1 or air
strippinJ at elevated t-., ~turM. 'Ib8 (. .'.'''{''uter ~. ¥OSed that the
destruct:.iat of argmUc 0. ..t.::mx:Js ao). .., ,lished by a bioloqical 14~ an::l
DL1d1 lower cperatin;r costs 8y make bioloqical ~~tia'1 a mre
~Labl. ted1nique to a(). .'I'lish removal of soluble organic
c:x::ntaminants iran the gram::lwater.
"
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7
EPA Resca~:
Bio.-.Aii~tiat technologies were evaluated in the FS and screened Olt
because the uncertainties assOciated with these "emergint' tedmologies
were greater than dechlorinatiat and other innovative tedmologies. 'the
problems associated with biOl&._iiatiat are:
1.
Maintenance of the prcper envh\oSlIUC< for the micro-organism
p::pllatia\S ;
2.
.
High f!SV!I.IT.JY requirement to breaJcdcwn large ~lex molecules
sud1 as PCBs. 'lhis translates into l~ retentia1 times to
~lete the reactiat;
Mass transfer is greatly rMt~ withcut aqitatiat by a
reactor, thus reducin; the speed and effectiveness of the
reactiat;
3.-
4.
Variable soil cc:n::U.tia\S of the site may result in irx::cnsistent
flusbilq, lilli:t~ direct CXI1tact between mic:ro-cm;ani.sms am
CCI'Itaminants (PCBs), an:t;
Large areas of larx:t wculcl be ~ it bi~-.A'Ii~tia'1 were
UplementeQ usin:J a larx:ttamin) technique. As stated in the FS
and the lU), the land surra.D'Itin:J the Re-Solve site is
pt:~i l'\8l1tly wetland rescuroe areas,' thus limi~ the
Uplementability of certain tec:hnologies ~ large areas
of larx:t.
5.
'D1e deep penetratiat of R:B in the vicinity of 58-25 makes it
increasin:;Jly c1iffic:ult to maintain an envi1.~1I&II::l1t suitable for
bi~~tia'1 (Le. ~te SJR)ly of ~, nitrogen am;or
methane) .
If dechlorinatia'1 does net prove to be iDplementable at the Re-Sol ve
site, EPA dce8 net ccnlic1er it logical to evaluate a less develc:p:d and
less iJzplementable tec:tmolcgy, sud1 as biw.a.-._ibtiat. Rather, the
1qD::y will evaluate a tec:hnolcgy that is further alCD;J in the
dev8l~ltal ~~ so that clear&Jp at the site can be initiated in a
tim8ly D8r1n8r.
6.
B.
'.t!DIaaL
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8
pcssible precautia1 to avoid adverse iJlpacts on the sur:r'aJI'Xti.n
nei~ am envira1ment.
EPA ResDa 1Se:
EPA will devel~ a site specific \WOrXplan, health ani safety plan
and project operatia1S plan for all pilot st1xlies ani additional
field work c:xn:1ucted durin; the ~hl) design. 'Ihese doCI~nts
will be available for PJblic review at the infomatia1 repositories.
As part of arrz field st1xlies that will entail excavatia1 ani
treatment (i.e., dec:hlorinatien), an air DDlitorin;J p1:~Lam will be
iq)lemented to prevent adverse iJJpacts to cn-site ~ ani neartIy
residents. .
i1. amnent:
'lhe Sierra Club asked whether EPA had identified arrz specific
criteria by t.ihidl to evaluate the pilot testir¥) of dec:hlorinatien,
am to detendne if dec:hlorinatien will be used. In additicm, the
Sierra Club ~ that EPA quickly px~ with the pilot sbxiy
so that the bacJcup optien can be brcuI:j1t en line in a speedy fashia1
if unanticipated problEmS arise in the pilot testir¥).
EPA RescoIISe:
Specific evaluatien criteria to be used to a9<:"$S whether
dec:hlorinatien can be iq)lemented effectively will include, b1t oot
~":'~ily be Umited to, the foUowin;:
Identific:atien of the specific d1emic:al v "'I~ of the
reactiat byproduct:s (i.e., sidestream);
1.
2.
3,
4.
5.
6.
, '
7.
Volume and OCI~.t.Qtia1 of the sidestream;
Plab.Mment;treatment requirements for d;~l of the
s:i.d..t.am and aCtC!l'lt'"iated costs;
Effect1V81eSS, of different reagents in the process;
Pl~ time;
Pe1:'Oent reductien of total cn:qanic:s in soils; and
0V8rall project oest.
EPA will be negotiatin;J with the PRPs for rea:Nerj of past cxsts inoJrred
by the ~Ulla&tt and the ccn:!uct of the J:IIIIWIb1 design and J:IIIIWIial
actien duri11;J the winter of 1988. EPA anticipates that the pilot sbxiy
at the dechlorinatial prOCa:IS will be a:nmcted durin;J the sprin:;V~JlftN:ar
of 1988.
. ,
, ,
"
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9
iii. n .,.1..."".:
'lW v..,.,~d:ers (the ~ierra Club ani the Town of 1:Br'tJrDlth) were
CCI'1Ce1'ned about the byproduct:s of the dechlorination process. '!be
Sierra Club advised that, durin; the pilot study, EPA shcul.d asS""C'':f
the prOOuctia1 of res; mtA 1 S, their toxicity level, the amount
produced, ani the facilities ~""UY for their r1;~. . In
aatitia1, the Sierra Club ~ that potenti.al problems related
to r1;~ of residuals fraD the dech1orinatiCl'1 pJ::ooess be ~red
to these associated with the different methods of incineration of
this waste material.
EPA Resoonse:
EPA will identify the specific c:bemi.cal 0. .'\ .:merrt;s of the reactia'1
byproducts of the dech10rinatiat ~u.-s as well as est.iJDated
volumes durin; the pilot study. As r1 i c:t""I ''''''*'Cl in the R:>D, EPA' s
HazarI::bJs Waste ED;ineerin; ~!S-:\rCh I.aborato~ (HWEm.) in J:W.uth,
Minnesota recently cx:apleted bioocn;::II:::IIt.cstiaybin~~~I1M11 ation,
DUtagenicity, ani toxicity tests at the byproducts of the
dechlorinatia1 pzooess. 'lbese tests cxn::luded that the byproducts
did net bi~1M11 ate, did net cause DUtagenicity, nor were they
toxic to aquatic~. EPA will a"'-~9 the need to ocnduct
additiaal tc:od.city tests at the byproducts durin; design. In
cD:litia1, EPA will MtA""ine the prc:pr manner in wch to ni~
of thes e. byproducts durinq design. .
As DEntimed previa.1Sly, ate of the evaluatia1 criteria will be the
additia1al ~,_/.t of the byproduct:s fraD the dechlorination
pl~. If r1;~ of the byproduct:s proves to be both difficult
ani ccstly, thus iJIpctinq the iq)lement:ability of the t.ed1nology,
EPA may cxn::h.1ct a ~rative analysis of the r1i~ of the
resim UII 1!11 for both dechlorinatiat an:! incineratiCl'1.
i v . a.uU8::I tl:
'.,
'!be Sierra Club urged that the results of the pilot study shcul.d be
tully evaluated before goiD.:r at with ded1lorinatiat. In additia1,
tb8 TcwD of Daz:t:8aI1th an:l tbe Re-5olve ex:. urged that all data that
18 ~:i._&Uy beb1; gathe%'81 at sites bein) treated with the
d8cblarlmt.iat PU)QeaSs shculd be available for review prior to the
start: of the pilot study at the Re-Solve site. !\Jrther, the Reo-
selva ex:. stated that data traD the pilot study at the Re-Solve site
shculd be made available for MView (a PJblic hearin;J) before .
CCI'1t:ira.1i.n with the ded1lorinatia1 pt~.
~
EPA ~)SS:
As JDeI'1t.iawd previcus1y, a warJ
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111'
,.
~.
10
dechlorination precess. EPA will tii ~'~9 the status of
dechlorinatia1 am the results of the pilot study durin; a ~lic
infomati~..meetin; durin; the ccn:iuct of ~i~l design.
v.
~nt-:
one 0 ....~ iter asked ab::ut the size of the pilot Study. Another
0CIJIIIente.r asked when the pilot study wculd beqin.
EPA ResDaLge:.
EPA antipicates usin; a (2) amic yaJ.'d pilot unit, the same unit
that is to be used at the Wide Beach SUperfund site in Sa.tth Glens
Falls, New York. EPA plans at ~ the pilot study during the
Sprin;J/SlmIDer of 1988.
b.
1.
ClsiIrq) Isvels
t\ _...~l1t:
'!be Sierra Club ,:u...-.ited that EPA's lA'~ cleanJp level of 30
Dq/Ja; ~...cul..cstiat of PCBs in cn-site soils in the saturated zcme
is identified with a risk fact:ar of 10 -5 ard an "average case"
scenario for "direct CX1ntact with soils".. .
'!he Sierra Club pointed cut that the "plausible may; 1111 11ft case"
scenario identified a OQu.~::u~atia1 of 1. 0 ~ for the same level
of risk. '!he Siena Club re.)o ....-'1ded that EPA take into aoQOUnt the
"Plausible 'INIvi-- case" rather than the "average case". In
additicm, the Sierra Club stated that the FS does not CXIItain volume
estimates that wculd OO&..~d to mare striD;Jent cleanup levels
beya1d the graph p1._Je&tted in FiguJ;8 4-2. Sierra Club requested
that EPA pz:ovide l'UDBJ:'ical estimates of these volumes and any
oon;~di.n1 adjUDl-.1ts in clearl.1p ccsts that wculd result if the
"JDayi1lll1lft plausible case" were use:i. 'Ib8 Town of DarbDcuth
CD1seJ:vaticr1 n--i -iat argued that the 1A'~ 30 Dq/Jcr;J cleanup
l8V'8l far PC8-cD1taminated soils and the oon~din) risk level of
10 -5 8bauld be wighsd against a tu:g8t level of 20 Dq/Jcr;J and the
--~1ated risk level in cm:1er to reduce p.Jblic health risks at or
adjacent to the Re-Solw site.
EPA ~:
Based upc:n a p1ll'hn- of reua1i!Ible and valid (albeit cxn;ervative)
a-"'t'tia1S, EPA CXI1Siders the avenge case 1.D'D!r future site use
a:n1itia1S to be prot:act.iw of human health am the envircnDent.
'lbe w..-~t River Defense F\Jnd (WRDF) ~ these .)o....oAl)ts of the
Sierra Club by reference.
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11
'I!1e estimated volume of ~ted soils located in the
unsaturated Za1e greater than or equal to a cxn::entra.tion of 1 RE
is 30,000 cubic yards. '!he estimated total project cnst to treat
30,000 cubic yards of ~ted soils to a cleanup level of 1
RJD is $11.25 milliat. EPA has selected a cleanup level of 25 RE
for PCBs in soils. A target level of 25 RJD PCBs ~d still
CXu.",~d to a 10 -5 risk level. '!he ratiaBle for EPA's PCB
cleanup standard for soils is pres eilted in D:)re detail in Section
VI (B) (1) of the Record of Decisiat (RX).
iie ~nt:
'I!1e Sierra Club questia1ed the reliability of the berrh-scale
stmies in predi~ the interre1atia'1Ship of PCE!s ani volatile
oxganic ()o ..".lJUI'1ds (VCCs). Specifically, the Sierra Club was
c:x::n::erned that the 15 uses a l'I.DDerical ocrrelatiCl1 be~ the
c::r:n:entratiat of VCCs an:! PCB 1!d:>ility that is based CI1 the ben::h-
scale studies. 'Ihe o."'.'-'lter stated that if there is sufficient
~, the ~.¥J&ed PCB clean.JP ~~tt.~tiat levels may net
be sufficient to guarantee pm:manent iDa:lbility of the PCE!s to be
left ell site.
EPA Re:sI:xrIse:
'Ihe Drbility of FCBs in the groun:lwater is- depen:3ent at the voc
cxn::&1tratiat in the soil matrix. Results trcm EPA's benc:h-scale
study ani calculatims made usirq available literature at the
subject irxlicate that reducin;J VCCs to the levels selected in the
RD !C:NI1Jd render the FCBI mlatively iJmcbile. Please refer to
Sectim VI tA) (2) of t:ha 1Q) .fir a DDr8 detailed n;cn.1SSion CI1 PCB-
voc interactiat.
iii. 0 .1.1~J1t:
'I!1e Sierra Club (an1 ~ by reference) rBDa%iced that the 15 does
net ~.re the lerJ)th of treat:mBnt time required to adlieve levels
of clemJp far the d8chlarinatiat an1 the irx:ineratiat alternatives.
It cpstia&:I ~ me ar the other wc:W.d result in a
significantly faster clear11p, an1 if so, ~ the time savings
. wculd significantly affect additia1al off-site migratiat that may
cxx:ur .
EPA Resca1se:
, EPA estimates that the time of cperatiat for both dechlorination ani
iD::ineratiat of 25,500 cubic yards of PCB-cart:aminated soils ani
!IUIt'1;1NIa?1ts wc:W.d be the same. 'I!1e perioi of ~tiat is estimated
to be 24 DD'Iths'.
~.
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L
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12
c.
Air P!mi_iam
L
a...u.I8::I .t:
'Ihree cx:mDenters had remarks cx:ncem.i.n; p::rt:ential air emissions fran
dec:hlorinatiCl'1. 'lhe Sierra Club (am WRDF by refererx::e) questiOOEd
whether VCO:I will be released to the envira'me1t durin] the
dechlorinatiCl'1 ptOQe::jS. '!he Re-Solve c::AC l~.1:ed that previa.1S
experience has shown that durin; the exr::avatiCl'1 prooess, the ~
of VCO:I will be a problem. It questiCl'1Sd what 1IIA:II$IJ%eS will be
eaployed to cart:rol the emissiCl'1S, and whether an enclosure will be
used aJ:xJVe the 15' by 15' area beirq treated am, if not, why not.
EPA Resca 158:
'!he dechlorinatiCl'1 precess is a closed system. VCO:I released durin]
the reactiCl'1 step will be captured in vapor P1ase cartx:n am
di c;posed of properly. Mitgative 1IIA:IIc:lJreS such as those di "='""'1S'Sed in
5ectiCl'1 VI (A) (1) of the 1Q) and the evaluatiCl'1 of altemative SC-2
will be iJ!plemented durin; the EDCCaYatiCl'1 activities. EPA is
~~in:1 to use ~i ~im suppt iCl'1 t.edmi.ques such as foam or
water spray to cxntrol odor and dust durin; exr::avatiCl'1. 'Ihese
techniques are more effective ani DCr8 easily iJ!plemented than
CXI'1St.tuct.:i an enclosure over the excavaticm.
ii. lhIInPnt' :
0. ccmnenter was ~ with the possibility of air emissions if
the backup optiat of incineratiat is used am asked how 1m; the
ptOO=:iS wculd take.
EPA ~:
In accordance with 5ectiat 761.70 of the Toxic Sutst:ances o:m:rol
Act (TSC'.A), incineratiCl'1 systems DUSt dema !Strate a 99.9999 percent
destructiat and remaval efficien:y for:EaS. It inc1neratia1 is
selected, a trial. bum will be CXI1ducted to detetmine if the
incinerator achieves the requirements of 'lSCA. F\1rther, air
-.isaiC21S frcm the incinerator will not exr-.ed any Federal or State
8A}U.cable or relevant' and ~\o}Moiate envira1menta1 requirements.
EPA estimtes that it wculd take ~tely 24 JID'1ths to
incinerate 25,500 amic yaMs of FCB-a:ntaminated soils am
!CUIW'1 i MDrJts.
~-ts far DIta
~ _1.1~'tt:
A .~es.entative of the DBrt::mca.1th BoaI:d of Health nctecl that the
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13
chlorinated ~, t:ut that it is not clear whether or not this
met:hcd will 'NOrk specifically a1 PCBs.
EPA Resca 1Se:
o
Ben:h-scale testinq of the dechlorinatia1 process was cxn::hJct:.e::i as
part of the PS us~ soil ~les fran the Re-Solve site. 'lbese
~les oart:ained PCBs at 3000 AD. 'lbe dechlorinatia1 process was
eftective in reducin:1 the PCB cxn::entratia1 to less than 1 AD.
Refer to sect.ia1 4 of the PS tor additia1aJ. infOI'matia1 and data.
More reoeIatly, a pilot-scal.e study was c:c:IIpleted at the GE ~u
SUperftJrn site usin:1 a 40 galla1 reactor. PreliminaJ:y results
indicate that the dec:hlorinatia1 pr;~ was SlV'Y"aSSful in reducin:1
the PCB levels in soils fran ~tely 7000 R:D to 10 ppn.
'lbe specific Cyprcducts fran the dec:hlorinatia1 of the PCB-
CXI1tam:inated soils obtained fran the Re-Solve site ~ not
identified as part of the bench-scale st:Lx!y. EPA plans a1
identifyin:1 the specific Cyprcducts as part of the pilot-scale
study. Hcwever, there is ncpcssibility that dioxins will be a
byprcduct ot the dechlorinatia1 ot PCBs.
e.
Other
1.
~~:
A citizen was cxn:::ezoned that if'aJ:i:er treatJDent, EPA fin:1s that it
cannot use the !?Oil as backfill, then the timi.nq of cleanup may be -
delayed, and the price ot cleanJp may in::rease.
EPA ResDc.nse:
EPA selected a target treatment level of 25 R:D for PC:8-oa1t:.aminted
soils. 1his is Eq1ivalent to the health-based cleanup starxiard for
the sits. Usinl the dechlorinatia1 pl'OOe:::a, EPA will treat the
CXI1tam:inated soil tor a predet:emine:1 period of time (treament time
will be detemined in the pilot study). Followin;J treatJDent, EPA
will &aq)l.e the batch to dstemine it the 25 AD target level has
t.81 attained. It the level has been attained, the soil will be
U88d to tl8dctill 8XC2IV2t.ted areas ot the site. It the target level
ball net been attained, the batch will unjergo turther treabe1t
until th8 cleamp level is reached so that the treated soil can be
used as bacJctill. '!his plooeM shculd net iJrpact the time or cxst
ot the ~bl act:i.a1. .
i1. ~M:
5everal c" ....- aters asked far clarification regard:i.n;J qJtia1aJ. pre-
treatment of unsaturated a1-Site -soil.
-'
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14
EPA ~~:
nJrin; design of the ~ial alternative, EPA will oc:n:Iuct
treatability sbxlies to detem:ine if pre-treatment of soils will be
undertaken. If pre-treatment proves to be cost effective, then the
}qercj may decide to ~ this optiCl'1.
iii. ~dll.I-=I1t::
Q,e persa'1 at the p.Jblic hM.rin;;J asJcer:l whether the flushin;J of the
aquifer will admit PCBs into the aquifer.
EPA ResDoIISe:
'!be grcun:l-water ~tment system CCI1Sists of a recircu1atiat system
that will draw water in, treat it, an:! distri1:ute it over the site
so that thraJgh ~ washin;, the soils will be cleansed.
Bec:ause PCBs are relatively insoluble, they are net expected to be
washed. off the soils as readily as soluble organic 0.,\ oun:1s, such
as volatile organic 0. .'\-ounds (VCCs). 'D]8 rBIDVal of VCCs trc:m the
soil an:! grcun:l water shculd cause the PCBs to remain in the soil,
an:! tmJs Umit the possibility of gramd water CICI1taminatiat.
2.
~-.-IL ot v.;~.;~
01 ~....~.
a.
Gra.ni-Wat.er O:mtamin~ -tiat am JbU.t.arirq
1.
~nr:
'!be Town of D1rtnD1th urged that, in CDljunctien with ~ CI'1-Site
treatment of gramd water, a rigoraJs residential well mau.torin;
~~CWI be ~lemented to detect art! migratiCl'1 of ca'Itaminants. '!he
Town of D1rtnD1th ~ that EPA CCI1Sider the extensiat of
p.Jblic water SUFPlies to the area adjacent to the Re-Solve site if
~ m:i.gmtiCl'1 of a:I'1taminants is detected in residential wells.
EPA ~:
S8l8:::t: dcwr~ca1ient: residsntial wUs and mau.1:arin) wells will be
1ICI'1itar8d durinq the gramd-water r8t0ratiCl'1 pl.~CUII. If the site
related a:I'1taminants are detected in such residsntial wells at
levels that are a risk to 1uDan health, the.1qerr:y will umertake
OOtla..'tive actiCl'1 that rray inc1u::Je the provisiCl'1 of bottled water or
an altemate water supply~
li. ri.....--kt:
'D]8 Sierra Club expressed CXI'Dm1 that the Feasibility Stu:iy does
net MlJIIft; 118 the quest.iCl'1 of pXential CICI1taminatiCl'1 of dcwn:jradient
'.
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15
be..h.~ wells. It questia1ed to what extent ~ migraticm
t:.hrc:u;h L.:dL~ can be pre::lict.ed am whether, in EPA's <:pinion, this
is a' seriOJS ccncem. ..
EPA Resca 1Se:
D
Detem.inin; flat directiat in a tract:ured media is very difficult.
Ground water will follat fracture pathWays in respa ISe to potential
head c:hanges. In the case of the Re-Solve site, the ~iOJt River
and adjacent ~anjs creates a large drain or ground water
disd\arqe area for flat at both sides to seek. '1his is evident by
pieziaDet:ric head data from the site ~c:h iniicated upwa%d vertical
gradients and ~isa1S to similar basins in New En;Jland. '1heJ:e
is no questiat that there is ocntaminatiat in bedrock, but. EPA
believes that it disc:ha%ges to the cepiOJt River and adjacent
wetlands am therefore, does not pose a threat to dcwngradient
users.
iii. ~1.l.e1lt:
,
'lhe Re-Solve site c:x:. had several questicms re;ard.in; the ~.-tt
of migratiat phase of the Feasibility Stuiy, as well as several
requests for data. Its questicnl and ~cnI inc1uied the
followin;J:
Grcurd water IUlPlng and treatment shoul.d not be started \mtil
the hcrizattal c:list:ri):,utiat of all of the ocntaminants are well
defined. '!he CAe ~ that ather wells be drilled down to
the 1.-.h.~ but. not into it.
'!he c:x:. wculd like to see mre ~ to detemi.ne it there
are separate pw;es of dense nc.n---}I'eOJS liquids at tq) of the
~~ and/or at tq) of semi-pemeable silt or clay layers
mxma the L.:dL~?
'lhe c:x:. stated that, c:a1SiderirI1 that the Feasibility Stuiy is
based at 1983 data, it wculd like to see a CXI'1t:.:imum of the
data up to the point of the final clearJJp.
EPA - -. r.se:
'IbI hcriza1ta1 and vertical c:1ist:rib1t.ia of ocntaminants were
st",.Hed extensively as part of the RI t:.hrc:u;h the installatiat of 45
JllCldt.ari.rJ) wells. EPA feels that it has a geed understarr.tin: of the
,.H~ved P1a58 of the plums. In aa:l1tiat, 56 soil borin;Is were
installed as part of the RI and smlples were taken fNerJ two feet
and analysed for PCBs and total volatile organics ('lW). 'Ibis
~~ sents a18 of the most extfnIive soil borin; investiqaticnl .
c:x:n::Jucted tn date in Rsgiat 1. 'lhe results of this investiqatia'1
does not in:iicate the pt"5.sance ot I'DHIqUeCUS P1ase liquids. '1hi.s
detemi.netiat was based at residual OCI~rtratiat of 'lVCB in soils.
-'
I '.'
. ..., . ." - - I ~
-, . ' .
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16
. .
Finally, the fS is net based at 1983 data. Grcund-water sanplin;
data !ran as recently as July 1986 ~ used to characterize the
extent of contami.natiat' in the avert:lurden am bedrock aquifers ard
in the develqment of ~1;111 alternatives.
c. ~11e
"
i. 1l"1.1~~:
'1\10 o....-.1ters had remarks ~ the sc:bedu1e of the management
of migratiat phase of the clei!lJ11p of the R8-S0lve site. 'Ihe Town of
DartJDcuth stated that in order to limit migratiat of ocntaminants,
EPA sbculd o:n1ider i1ftnAtii;llte!y iJlplEllDBl'1t.in;J gramd-water treatment.
'Ihe Re-Sol ve CAe urged that any lack of experience with the
ded1lorinatiat process sbculd net be allowed to delay the startup of
grom:l-water treatJDent. It argued that since VCCs are respct1sible
for the Jll:lbility of the PCBs, their early treatment will oart:rib.rt:e
to cxm:rol of both prcblems.
EPA Res1:xx1se:
Dlrin; design of the p!ftWIb] actiat, EPA will a:n:1uct pilot-sc:ale
sttxties at the d8chlorinatiat pt~ as well as the gramd-water
treatment ~. ~!;I'es. '!he pilot study at d4dUorinatiat, therefore,
shculd not delay the iJlp1mentatiat of the lau=dy. sec:xnny,
treatment of PC::IkxI1taminated source soils will also result in a
percent reductiat of the VCCs. If the mass of VCCs in the
unsaturated Zate go untreated, a laJ3er period of time will be
required to restore the aquifer to the target: clean.Jp levels.
Finally I it the management of mic;ratiat Q ..", "IDmt is iJ!plemented
prior to the scuroe o.oIuLr.ul Q .'1 -aalt, PC::IkxI1taminated --ni_'1t.s
will CXI'1tinJe to act as a source of contami.natiat for an ad:titia'W.
10 years or more.
d.
WetlardB
i.
l'!t ..e.... at:
~ Sierra Club (an:! ~ by ret'ce~) an:I the Town of DartJDcuth
wm both ~...med with th8 etfecta of the r--'bl actiat at
W8tlan::Js. '!he Sierra Club asked whether the "replaced" wetJ.arx!s
will be a:mtigucus to the CI188 that will be altered or destroyed.
It asked \Ihether "repl~-It" refers to regeneratiat or enlargement
of an existin;J wetland system, or to an atteapt to "create" new
wet.lar1ds. 'Ihe DartJDcuth O:I1setvatiat ~;qiat 9I~ the
i4~ cleamp l8Y8ls for trIAt't;~ in the wetJ.an:m because of the
possibility of amt.:imB1 migratiat of cxrrt:aminant:s dcJwn;Jraclient.
Hcwever, the Town argued, the methcdoJ.cgy for ~ in am
adjacent to the W8tlan::Js sbculd be scrutinizecI to avoid fUrther
contami.natiat an:I disruptiat in the WBtlan:I area. '!he Town made the
~.
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o
C.
17
follcwin;J ~a1S:
L-
CXI1taminated wetlan::!s should be isolated with a P1Y'sica.l
barrier (silt fence and/or berm) or flow patterns should be
rec1:irected; arxi
CXI1taminated wetlands should be excavated i~iately arxi
stock-piled in an uplarxi area.
EPA ~:
'Ihe selected z-ihll actiat entails excavatiat of 3000 O1bic yards
of PCB-cx.ntami.nated c:arfi~ in the wetlands north of the site an:i
the unnamed tribJtaJ:y. Mitigative 1IIAaCZlJreS that will be undertaken
dI.1ri.nJ the c:x:I'1duct of these activities are di tC:t"'I1C!"""'" in detail in
sect:.i.a1 VI(A) of the IQ). 'lhese activities will result in the
t:.eqx)razy less of wetlam areas. Up:n CXIIpletiat of the ~i;"1
activities, a wetlarxi restoratiat p1~cuD will be i:q)lemented
involvin; the in-kind repla.--PJt of wetlands.
In order for EPA to "excavate" the PCB-cx.ntami.nat.ed -ni~.
"i1lWNW'1iately am stockpile th8 in an uplan1 area", EPA WI11ld have
to o::nduct a 1"E!DI:MU acticn at tbe sitae A J:"EIIICYal. actiat requires
that the CD!tc8inant:s pcse em Dainent ani sutIstantial dan;er to
public health and welfare (see 5ectiat 104' of c:m:tA) . EPA does not
believe that the PCB CXI1taminatiat in the wetlands qualifies for
I"E!ICYal activity, or that I"E!D:IVal activity is ~,-¥riate.
CXJHmT! REr.ATICH; ARC RJBLIC PAR1'l:CIPATIal
1.
n ...I_llt:
Q1e ." ....-leer (WRCF) stated that EPA sbculd place greater ~is
at nctityin:;r the pmlic of the exi.st:.erD! of the site, arxi that
waminq sigrw shculd be posted about the fish am surface water
CXI1taminatiat. It was suggMted that all area realtors be sent
ocpies of all bulletins arxi nctices at the site.
EPA.-
-awe:
In the .-... of 1986, EPA posted waminq signs in the vicinity of
the site alert1n) the public against ~at of Amercian eels.
As ~, these signs will be replaced. 5eccn:U.y, EPA has
d8velcpd an extensivemailin;Jlistofinterestedpersa.1Sin the
~"1ity surroun:1i.n;J the site, and EPA W1el.ccmes any new ad1itions
to this list. .
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-'
D.
E.
.
18
i1.
a......8 I 8118!"-.t, :
'Ibe Re-Solve CAt: asked if there ~d be ~irq cx:mrunication with
~ of the public to infom them of the pI~~ of the cleanup.
EPA Resconse:
'Ibe l'rmWnInUty relatiam activities will CXI'1tinue after the RecxIN of
Decisia1 has been signed. EPA will centime to hold public
meet:.i.n;s, and issue fact sheets to intom the public of events gem;
a1 at the site thrtIughcut the ~lementatia1 of the r--IIi~l actiai.
EPA cx:nt:inJally updates its mailirq lists, so that intere.st:ed
--ners of the ~trUty can receive infozmatia1 directly.
ersT AND mmnc ISSC!S
1.
a...i&L8::llt :
'Ibe Sierra Club o.....-utsd that it a_- the State of Massad1us8tts
will pay cp!ratia1 and maintenance CXISts unless and until
respalSible parties agree to pay these CXISts. '!be Sierra Club
questiCl18d whether EPA has ck:ne artf analysis of what effect the
excavatia1 and treablent ~ greater vol~ of soils ~d have a1
the 1aJ;J-term cpera~a1 and maintenance CXISts associated with
grcund-water treatment.
EPA Rescot 1Se:
'Ibe O.,.,...-"'lth of Musadmsetts will provide 10' of the capital
CXISts and cperatiat and maint:a1anca CXISts thrtIughcut the
.bplementatiat at t:b8 l.--dy. Seca1dly, EPA cxn:Jucted a limited
analysis of the effects that treatment of different volumes of soils
wculd haY8 a1 the rata of restaratia1 of the aquiter. 'Ibis analysis
is ~ smtad in the tachnical D&DOrandum entitled ''Re-Solve Aquifer
Flush:in; 'lW:hnical MeIacr8ndum" whidl is included as part of the
Administmtiw Raand for the site.
1.
~
r1.._.-llt:
Several O.'.'~lters asked ab:ut the status of the negotiatiCl1S with
pctentially respa1Sible parties to mccver past am futum c:x:sts.
EPA ~0I1Se:
FoUowin;)' the i CI6UanC8 of a Record of Decisia1 (RD), EPA will
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()
"
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19
, .
incurred by the Government an:l for oc:n::iuct of the ~ ial design
an:l ~;"1 actiat described in the Record of Decision (roo).
P.
~
. .
Mist-11.anecus <> ...._1 Its inc1med these regarciin; the clearu.1p schedule,
site ~", the extensia1 of the . .....-at period deadline, EPA oversight
of the ~j"l actia1, an:l qualificatia1S of cn-site persamel.
a.
~ ~11e
1.
0:rrInent: :
'!he WRDF expressed ~ that the clearu.1p beqin in advance of the
projecta:i earliest start date ot 1989. It noted that the citizens
have been dealirg with the prctIlem lCD}er than ~sary, as a
result of a tailed clearu.1p at:t.eq7t at the site in 1983.
EPA ~:
First, EPA is required to negctiate with the PRPs tor ret::DIIerf ot
ccsts incurred by the ~UI_at an:l for CCI1duct of the ~i"l
design/plMribl actiat. If negotiaticras tail, EPA can then
~lement the l~ usin; the SUperfun:1 Trust!Un:t. EPA
anticipates that the design of the ~;" 1 actia1 will be
initiated, by either EPA or the PRPs, in the Sprirg of 1988..
~i ;!I] design ~ l' Y takes 9 to 12 Ira1ths to CCIIplete. Sprirg
of 1989, therefore, is the earliest possible date that the selected
~;;!Il actia1 oculd be initiated at the site. .
secxn:uy, the first r-w-ibl actia1 CCI1ducted frc:m JUly of 1984 to
JUly of 1985 was SUO{"-8tuJ. in peDI8nently an::! significantly
reducirg the volume ani taxicity of PCB-oa1taminated source material
at the site.
ii. ~I.I-jlt:
Q18 cit.iz8n was o:.~ that, since the dec:hlarinatia1 process is
8ti1l in the pilot staI:J8, in several years EPA my fird it made a
1I18taJca c:bxISirg decblarinatia1 as an altemative, an::! thus clearu.1p
of the site will be delayed even mere. 'the citizen ~
c:bxISinq an n~lish8d ~~.n
EPA Res1:x:11Se:
EPA will evaluate the ~lementability of dec:hlorinatia1 t:hrough the
cxn:Jix:t. of the pilot study prior to final selectia1 of the source
-"1L.\Jl treatment tec:hnology. '!be CCI1duct of a p~ot study will rxrt:
delay the initiatiat of the ~; ,,1 actia1 at the site.
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.i.
20
, .
b.
Site 1-1 ,.~
li."...lCIll:
'!he Town of Dart:nD1t:h requested that EPA ad11.~ short-tam and
la'I;J-t.em :II~9 to the Rs-Solve site and surrc:un1irr;J areas.
EPA ~:
As part of the ~i ::.1 design of the alternative, EPA will initiate
enfor~ ¥-=wdtt:s am,Ior actia'1S to ensure. short-tem and lcn;r-
tam -~ to the Rs-Solve site.
c.
Emndc:n of n_._._~L Pericd,I ~-t tar Ifeet::iD) with EM
i.
a. .8._I.UIdTt::
'Ihe Rs-Solve CAe requested an extensiat of the (k .'.'-It pericd
deadline, anc1 requested to meet with EPA to di""'1- -1_-., regard1n;r
the sits and hew the CAe can be of help in the cleanJp ~~.
EPA ResDa1se:
In respcnse to the c:xmDenter's request, EPA extemed the public
~'1t pericxl until July 31, 1987. In additiat, EPA anc1 ~ ~
met with the CAe at July 15, 1987 to d-lCt"l1S8 the role of the CAe in
the l--dy selectiat process, the alternatives 1A S).11ted in the FS
anc1 the Pl.~ Cleanup Plan.
i.
rl......I~nt:
Several ~.'.'_lters expressed cx:n:mn that careful JD:I'1itorin;J of a1-
site activities be oc:n:iucted. WRDF urged that EPA carefully JID1itor
the CXI1t:ractars I'eSpCI1Sible for the work. 'D1e Dart:nD1t:h
ODervaticl1 ~i lIUIiClt ncpst8cI that the Ar1IfJ CCt18 of Eh;Jineers
be actively involved in the iJIplement:atia'1 anc1 JD:I'1itor~ of the
c:le8mJp p;~. l'\.'.'-ltars were 0Qa~-ned both with who wculd be
avc:sJ1linJ t:b8 cleanJp, and who wculd be entorcin;J applicable
regulataty standards.
EPA ~ ~:
In teD& of CMlrSight:, if EPA is funding the cleanJp, EPA may either
enter into an int:aragency &.ll--tt with the Corp of Eh:}i.neers to
CDD.Jct the design anc1 oversee the OCI1St:ructi.at of the ~ ial
activities or EPA may enter into an ¥--It with a private .
CXI'1b:actor. In either case, an EPA official wculd be ~ s !nt durin;
the iq)lementatiat of the ~bl actiat. If the PRPs agree to
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o
~.
21
perfom the ~;" 1 actiat, they will hire their own contractor to
perfom the work, an::! EPA will carefully oversee this work. In
!:II_ry, the EPA will be ~ sent at all times, whether private
sector or government mcney is spent, to ensure that the ~ial
activities are o:n:!ucted ocnsistent with the Record of Decision.
e.
01l1li1 i ficat.i.a1s ot at-site ieJ:-..-l
1.
l"nIwnP-'1t". :
one ('J. ......:.1 Iter at the public hearinq was a:I'O!med about the
qualificatia1S ot the pecple wcrkin;J at site.
EPA Re$ca IS(!:
'!he qualificatia1S sought for at-Site persamel will be dete.nnined
durin; the design of the selected ~;,.1 action. EPA assures that
. atly qualified pecple will be invclved in the inplementatiat of the
~;"1 action.
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22
MR'l' II. a»mN1'S FIO! POl'!m'IALLY RESPC:R;IBLE PARTIES
IN'l'RODUCTICN
The following section summarizes written comments subadtted by and on
behalf of the Re-Sol ve Generators COIIIDi ttee (COIIIDi ttee), and provides EPA
responses to these comments. The COIIIDittee represents potentially
responsible parties (PRPs) at the Re-Solve site. Comments were subadtted
on behalf of the COIIIDittee by (1) ERT (Draft Feasibilit~St~ and .EPA
Preferred Alternative) (July 31, 1987), referred to as e EaT Review
Comments"; (2) Goodwin, Proctor & Hoar (ARARs) (May 21, 1987); (3) Nutter,
MCClennan &.Fish (Additional Comments on-rs--and Preferred Alternative)
(July 31, 1987).
A summary of ERT comments and EPA's responses appear below. Any
additional comments by Goodwin, Proctor & Hoar are also included below.
For the most part, the Goodwin, Proctor and Hoar comments are reiterated in
the ERT comments. Comments similar to those in the ERT document are
cross-referenced to avoid duplication of comments and responses. Also
included in this section are the comments sutai tted by Nutter, MCClennan
and Fish wi th a point-by-point response by EPA to these comments.
The Goodwin, Proctor and Hoar coaments were originally sutmitted to EPA
Region I on May 21, 1987, prior to the initiation of the public comment
period. '!.'hese c.\JII8III:uts were resubad tted on July 7, 1987 to T..ee M. Thomas,
Mninistrator, u.s. £PA. Winston S. Porter, Assistant Mninistrator,
Office of Solid Waste and Emergency Response, u.s. £PA, responded to these
comments on behalf of Mr. Thomas in a letter dated Auqust 13, 1987. This
response is included as part of the Mninistrative Record for the site.
£PA'S response to an information request from ERT (July 14) is contained in
a letter dated JUly 23, 1987. This £PA letter, responding to cost and
design data requests, is included as part of the Mninistrative Record for
the site.
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23
A. PRP CCItIa!NrS af TSE PUBLIC BI!'AL'DJ 1!:VALUM'Iaf
1. Technical 0
.,ts on 'lbe Public Health Evaluation
a. Selection of ~cals for AsseSSEnt
i.
Comment:
Section 8.2 of the report is of considerable importance
because decisions made in this section essentially drive the
Public Health Evaluation (PIlE) performed by camp Dresser &
McKee (CDM). It is critical to subsequent sections of the
report because all present and future site risks estimated in
the report are based upon the indicator cheDdcals selected in
this section. One apparent deviation we have noted from EPA
protocol concerns the use of non-detectable sample values.
This is contrary to the intent of the EPA document "Superfund
. Public Health Evaluation Manual." On p. 24 of this manual
the use of non-detect values is discussed and we quote"...
the mean should generally be calculated based on samples
where the chemical was detected, not includinq samples below
the detection limits." And in a subsequent sentence, "Be
sure to be consistent for all chemicals wi thin the medium 10
that the selection process is not biased." em page 25 of
this manual a sample calculation sheet is provided, and zero
was used for each sample in which the chemical in question
was not detected.
The CDM method for selectinq Indicator Chemdcals used a
qecaetdc mean that incorporated every sample taken at this
site. Because each chemical was not found in every sample
taken at this site, CDM assumed that all non-detectable
values ~d be treated a& though they were equivalent to
one-half of the detection limit for that particular chemical
(p. 8-3). 'ftUs approach adds considerable bias to the
indicator scores frcm which site indicator chemicals are to
be selected. one problem associated with the methodoloqy is
that the geometric mean tends to generate a mean value that
is closer to the values most often reported. The addition of
value. for samples oriqinally reported as non-detectable for
a chemical drives the mean value CDM has calculated towards
the detection limit value. As each chemical may have a .
different detection limit, the .an for each chemical is
driven towards different minimal values under the CCM method.
A second problem is that the CDM method generates a mean
value that is highly influenced by the number of samples
actually reportinq non-detectable values. As the number of
non-detect& varies for each chemical, the "adjustment" that
is made towards the detection limit by this method varies for
each chemical.
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24
EPA Response:
'l11e Superfund Public Health Evaluation Manual (PHE) was
developed by EPA to provide guidance in conducting Superfund
site PHEs. EPA did not intend that the PHE manual be treated
as the only approach for conducting PHEs and, in fact, few
PHEs rely exclusively on the PHE manual approach. With
respect to detection limdts, it is standard practice to
consider samples in which the contamdnant was detected along
with samples in which the contaminant was not detected in
calculating a mean value. EPA has specifically recOlllllended
that half of the detection limd t value be used in calculating
means for hazardous waste si tes (EP, Exposure Assessment
Methodologies for Hazardous-Waste Sites, May 1984). The use
of zeros for non-detects in calculating the mean may bias the
o mean estimate downwards whereas use of the reported detection
limdt in calculating the mean may bias the mean upwards.
b. a.an Bealth Risk AsseSSllel1t:;Potential DllYelq'8l!l1t of the
Re-Solve 5i te
i . COIIIIIent:
Section 8-30-31, as written, makes no real attempt to discuss
the uncertainties inherent to this particular risk
assessment; instead, it provides only a short, generic
discussion of those factors that typically add uncertainty to
all endangerment assessments. CDM has made no attempt to
discuss: 1) the uncertainties associated with their approach
for selecting indicator chemicals, and how this uncertainty
affects the outcome of the risk assessment, 2) the
shortccainqs of the exposure assessment, 3) the limi tations
o of the sampling data, and 4) they made no attempt to identify
those components of the risk assessment (i.e. variables in
specific equations) that may alter the perceived risk
estimates that have been provided in this document.
EPA Response:
'1'be uncertainties assoc:iated with the select~on of indicator
chemicals may result in an underestimate of risk (by less
than 1 order of magnitude) since not all chemicals present at
the lite were quantitatively evaluated in the risk
a...ssment. There are many uncertainties associated with the
exposure assessment, and most of the assumptions used to
compensate for these uncertainties may overestimate risks (in
most cases - by less than 1 order of magni tude) . These
conservative ass\.1q)tions include assuminq that the frequency
of exposure and contact rates with environmental media are
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25
data used to calculate uncertainties are associated with the
limi ted number of samples used for several exposure pathways.
(4 for on-site surface soil, 6 for off-site surface soil, 3
for on-site VOC air concentrations, 1 composite fish sample
from the Copicut River). The uncertainty in the sample data
may result in either over- or under-estimation of potential
risks (probably by less than 1 order of magnitude).
Coument:
H.
How can a sample be both an off-site and an on-site sample?
A comparison of the listed on- and off-site surface soil
samples shows that COM used S&-47, sa-SO S&-S2, and S&-53 as
on-site surface soil samples. Yet three of these are
actually off-site samples, so that only one on-site surface
sample was actually used. It would appear that a major
limi tation and uncertainty of this PRE is the inadequate
number of surface soil samples collected during the remedial
investigation. (See ER'1' review cClllDents 149 and 151). It
would be better to consider all soil samples for the purposes
of calculating exposures. This would produce an apparent
geaD8tric mean of 0.310 ppD for PCBs (p. 8-12, 8-79 based on
CDM's method of calculation).
EPA Response:
There are a total of seven surface soil samples collected
during the 1U. Among these only one (5847) was collected "on
site". However-, for the purposes of developing exposure
point concentrations, it is desirable to roughly characterize
an "average" and a "plausible maximum" level of on-sit~
contamination, and such a characterization should rely on
more than one sample if possible. Three of the surface soil
samples (SBSO, SB52, SB53) were located just outside of the
site's fence and thus were formally "off-site" samples.
However, these samples were located close enough to on-site
areas to characterize potential on-site levels of
contamination and so they were used in estimating exposure
point concentrations both off and on site.
Certainly more surface soil samples would have been useful.
Hi. Calment:
The possible number of times a child may visit a site is open
to considerable debate. As previously noted (See ERT Review
CCIIIDent 153), it is highly unlikely that a fence erected at
this site would be knocked down and remain down for any
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26
extended period of time. Moreover, children are in school
during every month of the year except June, July and August
and even during the summer a small child is more likely to
play near home. In addition, the ground may be wet,
snow-covered or frozen a considerably portion of the year in
Massachusetts. All of these factors would act to decrease
the number of times a child is likely to gain access to the
site. thUs the maximum number of visits per year (50)
selected by COM seems unrealistically high. Given the fact
that very few people live near the site (p. 2-1)" 25 visits
might be considered a better maximal number.
EPA Response:
It is important to understand that a PRE evaluates the "no
action alternative," Le., no institutional controls on the
future use and developDent of the site. It is with this
mandate in mind that the exposure pathways and scenarios are
developed. Thus, we agree that the plausibility of the
exposure scenarios should be considered. But under the no
action alternative, it is in fact quite possible that a child
might trespass onto the site area 10 tu.s per year for a
period of 5 years (see Table 8-10). In addi tion the PHE
focuses on the potential heath risks to the individual
as well as to the population. Thus, it was not considered
unlikely that one child living near the site might trespass
onto the site 50 times per year for the maximum plausible
case. '1'his corresponds, for example, to 3 days per week for
the. 3 summer months (36 days) plus 1 day per week for 2
months in the spring and fall (16 days).
iv. Coument:
The estimates of dermal soil adsorption are exa9CJerated. COM
recOCJnizes that others have typically used values for the
surface area of exposed skin that are smaller than the values
which CDM finally selects. Thus, COM fails to recognize that
children will not soil both upper and lower surfaces of the
handa, nor will they soil their arms to th, same extent as
their hands. ror this reason, the 1700 em area provided by
Hawley (1985) and ci teet by CDI would have been a IIIOre
reuonable I1UIIIber to select. "
EPA Response:
The exposed surface area estimates were based on a published
EPA report and were conservatively developed for use in the
PHE. Had a 1700 emz surface area been used, however, the
risks for this pathway would have been reduced by a factor of
0.63 for the average case and 0.50 for the plausible maximum
case.
--
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27
Comment:
v.
COM generates Table 8-10 (p. 9-36) using only the highest
soil exposure rate (1.5 mg/cm ) and only the highest surface
area (for a 15 year old). A more plausible estimate for the
average exposure scenario would be an average soil deposition
rate and a much smaller surface area. In addition, the
ingestion of soil (pica) is not practiced by children this
age and should be omitted from Table 8-10.
EPA Response:
The average soil contact rate of 1 9IVisit was calculated
using the lower soir exposure rate and the lower surface area
estimate (0.5 mg/cm - 1.3 9IVisit), not the higher exposure
rate and surface area estimate as suggested in the comment.
The soil ingestion rates in Table 8-10 are not applicable to
children with pica, in contrast to the comment (see Appendix
C of the PRE).
vi . Comment:
CDM applies the 'l'CDD soil bioavailabili ty data of Poiger and
Schlatter (1980) to PCBs. Why then does CDM inflate the
dermal absorption from a range of 0.3-3\ to 1-5\1 There is
no justification for this change and CDI should adjust its
number and calculations accordingly.
EPA Response:
The dermal absorption estimates of 1-5% were conservatively
rounded off based on Poiger and Schlatter's (1980) results.
The use of the 1-5\ number rather than the 0.3-3\ numbers
could result in overestimates of risks by less than a factor
of 2.
vii. COIIIIIent:
The equation listed on page 8-39 describing the amount of
. chemical a person absorbs dermally or ingests during each
visit to the.site is incorrect. The second half of the
equation will nOt yield a number for a chemical in units of
milligrams, therefore it can not be added to the number
generated in the first half of the equation. As this number
is then used to calculate the risks posed by visiting the
site, it is not clear whether the risks posed in Table 8-12
(p. 8-42) are also incorrect.
EPA Response:
The last portion of the equation presented on p. 8-39 (in
brackets ~ estimates the amount of soil contacted. and ingested
..
, ,.
. . . , .
" ,,' . '. .
h'.. ,.". .
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in kq. 'Ihe remainder pf the equation estimates the amount of
chemical exposure in mq by takinq into account the
contaminant concentration in soil (in mq/kq) and, for VOCs,
the potential for volatilization. 'Ihis equation is not
incorrect as stated in the comment; apparently the units of
the parameters used in the equation were incorrectly
interpreted by the commenter.
vii i . Comment:
'lbe calculation that Cr»I has used to estimate the averaqe
lifetime exposure to site contaminants is incorrect. The
average body weiqht over the life span of an individual is
the appropriate weight to be used, not the weiqht they were
when they were exposed. 'Ihus, it would appear that risks
listed in Table 8-12 are 2.33 times higher than they should
be if only this mistake is considered.
EPA Response:
'ftte averaqe daily lifetime exposure is derived by estimating
the averaqe dose over the exposure period in mg,Ikq body
weight, usinq the averaqe body weight of the child over the
exposure period (30 kq), and then dividinq by the number of
days in a 70-year lifetime. 'l'hus, the equation on p. 8-40 is
not incorrect.
ix. COIIIDI!nt
Given the number of errors in CDM's equation (p. 8-41, Table
8-11), a more realistic PCB soil e~sure should be
calculated. If one uses the 625 em of exposed skin that
Bawler (1985) lists for a 6 year old, adopts CDM's 1\
absorption rate, and then calculates the avera9Po lifetime
exposure, the value would actually be 5.9 x 10 mg,Ik9/day
for the averaqe case. As more accurate exposure estimates
than those calculated by CD! indicate that other CDM exposure
variables are too high, it appears that CI)ft's exposure
estimate ia too high and by at least two orders of magni tude.
ror. thil reason, it would seem that better exposure estimates
and a.recalculation of the risks listed in Table 8-12 should
be performed.
ErA Response:
As noted in the responses to cOlllDl!nts vii. and viii. above,
the equations used to calculate averaqe daily lifetime doses
associated with direct soil contact are correct. Also, as
noted in the response to cOlllDl!nt vi., the dermal absorption
numbers may only slightly overestimate the risks by less than
a factor of 2.
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29
x.
CCIIIDI!nts:
There is no basis for the assumption listed under (d) (see p.
8-44, Table 8-13), i.e. that the maximum concentration is one
order of magnitude higher than the mean value. This
statement appears to be one that even CDH agrees with for on
page 8-45 CDM states "...the selected exposure point
concentrations could potentially either underestimate or,
more likely, overestimate actual average VOC air levels."
Methods should have been developed for extrapolating VOC air
concentrations under different meteorological conditions
rather than assuming it is ten-fold greater under worst case
conditions.
EPA Response:
There is possibly as much as one order of magnitude
uncertainty in the use of the VOC and particulate matter data
in estimating inhalation exposure point concentrations.
However. exposure point concentrations that could be
esti8ated by applying soil volatilization and fugitive dust .
80dels in conjunction with air dispersion DIOdels would have
at least as much or more uncertainty than that in the
measured data. Therefore, the measured data were used in
Section 8. The uncertainties involved in using such data are
noted in Section 8.4.3 and 8.4.4. It should be rec09r1ized
that there are many uncertainties involved in conducting a
PBB and tlma the purpose of the PHE is not to precisely
define human health risks but rather, to the extent possible
based on the available data, provide estimates of the
potential for risks to human health. Since the inhalation of
contaminants frCII the Re-Solve site was considered to be a
potential pathway of concern. the potential risks associated
wi th this pathway were estimated, but the uncertainties in
uain9 either axleled or measured data were seriously
CCII'1$idend in developing an approach for evaluating this
pathway. In add! tion, the decision to increase measured VOC
air levels to reflect potential worst-case conditions was
based on information provided in the peer-reviewed scientific
literature indicating that VOC eadssions may increase
sub8tantially under dry, hot condi tions relative to wet, cool
ccn:U. tions. .
xi. CC-nt:
~ ,
CDM has failed to use a consistent exposure scenario for each
route of exposure. Dermal exposure was calculated on 10
visi ts per 5 years; inhalation exposure was based on 10
visi ts per year (for only 30 minutes) for 30-64 years. This
divergence of exposure scenarios is not justifiable and is
used to exagqerate the inhalation exposure to a level above
that occurring under the first exposure scenario.
'-,' ", ..:
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EPA Response:
The direct contact exposure scenario was derived for an
individual assumed to trespass onto the site area and engage
in activities that would result in contact with and exposure
to contaminated soils. The inhalation exposure scenario was
derived for an individual assumed to pass through or next to
the si te area during which time contact (1. e. inhalation)
would occur. The direct contact scenario was limi ted to a
child because adul ts would not be expected to trespass onto
~e site and engage in activities resulting in soil
exposures. The inhalation exposure scenario could not be
limi ted to a child only because adults could walk next to the
si te, thus exposures over a longer time period were evaluated
for this pathway (30-64 years). Considering the significant
differences in the exposure pathways and the factors likely
to affect the possibility of exposures, different exposure
scenarios were not only justifiable but also required.
xii. COIIIDent:
There is no basis for aSsuming that particulate levels might
be as high as 400 JDC,JIm3. Ambient particulate concentrations
are normally considered to be no higher than 70 JDC,JIm3.
EPA Response:
For the plausible maxiDLIID exposure case, the particulare
matter level was not assumed to be as high as 400 ~ as
stated in the caament. It was assumed to be 0.4 mg/ID. This
estimate is well wi thin background particulate matter levels
in Rhode Island.
xii. Ccmaent:
Site dusts will be camprised of both on-site and off-site
particulates, so the level of exposure has been overstated by
<:::I»I, a fact that they admit.
EPA Response:
see r..pense to cQllllent x. above.
xiv. CCIIaent:
CtII assumed that all particulates were respirable, an
overestimation of the actual percentage of particulates that
are respirable.
EPA Response:
Because there were not site-specific ~rticle size
distribution data, it was conservatively assumed for the PH!:
. -. -~. .' ~, ':' '.
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31
that all suspended particulate matter originating from the .
site was respirable. If only half of the suspended particles
were respirable, however, the risks would be reduced by only
a factor of 2, and thus would remain of the same order of
magni tude shown in Table 8-17.
Comment:
xv.
CDM assumes that the high concentrations found in the unnamed
tributary are representative of those found in the Copicut
River. As this is unlikely to be true due to dilution caused
by the size of the river, this overestimation of potential
exposures should not be used.
EPA Response:
The maximum plausible case scenario was developed to provide
an indication of the upper bounds of the potential risks
associated with dermal contact with surface water to assist
the decision-maker responsible for developing remedial
alternatives for the site. Thus the concentrations in the
unnamed tributary were conservatively used to characterize
potential worst-case c:ondi tions in surface water under low
flow conditions (i.e. low dilution capacity).
xvi. CallDent:
The numbers CDM has used for the average and maximal contact
with the site via wading clearly overstate the potential
problem. Given that upstream portions of the river are also
accessible in this area, and the fact that the numbers CDM
used reflect a person's use of swimming pools, lakes, etc.,
the potential contact time with water near the site should be
reduced accordingly.
EPA Response:
The parameters used to describe contact with surface water
were not overly c:anservative. 'ft\ey assumed that a child
could possibly wade a total of either 7 or 12 times per year
for a 5 year period. Considering the absence of information
indicating that children do lO1' wade in the Copicut River or
other. surface water adjacent to the si te, these assumptions
were considered reasonable. In addition, it should be kept
in mind that PREs can be used to provide an indication of
potential risks, not to precisely quantify risk. thus the
exposure parameters used in this scenario were developed to
provide an indication of the potential risks.
-'
.,. " ."
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32
xvii. COIIIDent:
CDM is once again being inconsistent in their approach to
exposure. The PCB water concentrations for dermal absorption
of chemical while wading (Table 8-18, p. 8-55) ranged from
0.52-1.2 ppb with a mean value of 0.53 ppb based on 2/15
samples with detectable levels. These same PCB
concentrations now range from ND-l.2 ppb with a mean value of
less than 0.5 ppb using 2/11 samples.
EPA Response:
The approach adopted is consistent with the exposure
scenarios being evaluated and, as mentioned in the response
to comment xi. above, different exposure pathways require
pathway-specific developDent of exposure parameters. In
order to evaluate dermal exposures due to wading in the site
area, all surface water samples summarized in Table 8-1 and
presented again in Table 8-18 were used. In order to
evaluate inhalation exposures to VOCs, emissions from the
Copicut River were modeled as a line source. A subset of
surface water samples was used to characterize potential VOC
concentrations in the river.
xviii.Comment
<:eM's tendency to estimate the exposure upon a single sample
which was taken from a species (eel) that is not a popular
sport fish is not justifi.A. In fact, none of the fish
species listed on this page are species generally considered
edible or prime game species. All tissue samples except the
eel sample are below the current Pm guideline of 2 ppD. So,
even though it is highly unlikely that an individual would
use this area for sport fishing, it is also highly unlikely
that their catch would contain fish exceeding the allowable
Pm limit.
EPA bsponse:
It is true that one composite sample of redfin pickerel and
A8rican "1 was used in the maximum exposure scenario.
Bow8ver, due to the effects of CCIIIpOsiting it is likely that
one of the fish included in the composi te had PCB levels
higher than 20 ppD. Furthermore, the highest detected
concentrations were consistently used to characterize the
maxiDuD exposure scenarios. 'fttus, the selection of the
composite sample (see Table 8-26) for use in exposure
Scenario I is entirely consistent with the exposure
assessment methodology applied throughout section 8.
It is true that more fish samples collected from more
locations would better characterize potential PCB levels.
~.
. ,
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33
o
It would be helpful to compare background PCB levels with the .
measured data to determine whether PCBs in fish tissues are
. site-related. However, given the widespread site-related
presence of PCBs in sediments in the site area, it is likely
that resident fish will accumulate some site-related PCBs in
their tissues and not likely that PCBs in resident fish
tissues are completely unrelated to the site.
For the purposes of evaluating the potential risks associated
with .the ingestion of fish containing PCBs, both a comparison
to standards and a risk assessment was considered useful.
Furthermore, the FM PCB limit in fish may be changed to 1
ppD in the near future.
xix. COIIIIIent:
The exposure scenario developed by CDM is unrealistic. The
exposures apparently stem from an individual living in a
house constructed on this site. In addition to the points
previously noted (see ERT Review cClllDent 159) the following
assumptions are considered to be gross exaggerations:
The exposure scenarios ignore the fact that if
developed, the site will probably be vegetated and that
a grass lawn will greatly reduce contact with site
soils. .
The portion of the person's skin that )'5 exposed ,for
this scenario is too high given variations in weather
and dress that occur during the year.
The adsorption factor for PCBs that CDM uses is too
high. .
-
Adults do not practice pica, and the accidental
ingestion of soils is unrealistic given normal hygienic
practices (i.e. washing soiled hands before eating).
The environmental half-life of each chemical was
ignored. Even it if was assumed that the half-life of
the.. chemicals was as long as 5 years, the soil and
water levels .would underqo 14 half-lives during the life
span of an individual. The effect of this constant
degradation would be to reduce the average exposure/risk
by a factor of about 100.
£EtA Response:
The purpose of the PRE, as mentioned already, is to evaluate
the no action alternative. If no remedial actions were taken
at the site, and considering that the site is in a
. residential area, it cannot be ruled out that at some point
in the future the site could be developed for a residence.
. - .._. ~- ~
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Under these conditions, the fact that this is not likely to
occur does not guarantee that it WILL oor occur.
Furthermore, it is clearly stated in Section 8.5 that the
future site. use scenarios are hypothetical.
It is entirely possible that an individual may live at their
residence for 70 years. Not all individuals in the United
States migrate to another residence over a lifetime.
The assumptions that were applied are standard EPA
assumptions for evaluating inhalation exposures. In
addition, the soil ingestions rates do not assume that adults
or children have pica. see response to comment v. above.
2. PCB Toxicology
a. CODIDent:
,..
It is a misconception that all PCBs are alike. In fact, there
are 209 different varieties of PCBs, and they have very distinct
properties. only certain ones - by no means, all - are arquably
toxic to certain laboratory animals under experimental
conditions. The toxicity of those congeners has never been
demonstrated to occur in the environment. Indeed, at most, only
indi viduals exposed to heavy doses of PCBs in the work place have
reacted negatively to the exposure by contracting chloracne.
Epidemiological studies, including the "Final Report of Greater
New Bedford, PCB Health Effects St-~" just released by the
Massachusetts Department of Public Health, do not demonstrate
that PCBs are toxic to humans, certainly not at the
concentrations that are found in the environment, including at
the Re-Solve site. In this regard, we direct the attention of
the EPA to the substantial body of literature that has been
collected on toxicology and epidemiology, and, in particular to
the writings of Renate Kimbrough, formerly of the Center for
Disease Control and now with the EPA. For example, in an article
enti tIed "Laboratory and Human Studies on Polychlorinated
Biphenyls (PCBs) and Related C~, 59 Environmental Health
Perspectives", 99, 104 (1985), Dr. Kimbrough says:
In humans, no adequate studies have been conducted
to judge whether lOng-term exposure to PCB is
alaociated wi th cancer, nor have any reports been
published which have properly studied reproductive
OUtc:aD81 of hiqh1y exposed femalel.
, '
,
. .
And in a more recent article entitled "Human Health Effects of
PCBs and PBBs", 1987, (Ann. Rev. Phar.macol. Toxicol. 1987,
27:87-111) Dr. Kimbrough concludes al follows at 106:
-'
...,. .
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35
o
In conclusion, various toxic effects of PBBs and
PCBs have been described in laboratory animals. In
humans, acute poisoning outbreaks have only occurred
following exposure to a combination of PCBs and PCDFS.
When humans were exposed only to PCBs or PBBS, the
only observed acute effects have been generally
minor. So far, no significant chronic health effects
have been causally associated with exposure to PCBs
or PBBs."
Dr. Edward EDmett of Johns Hopkins has been identified by the
united States as an expert in the epidemiology of PCBs. In a
recent publication of the Johns Hopkins School of Hygiene and
Public Health, the following apPears:
Not all of the 209 kinds of PCBs have the same detrimental
effects on health.
"Based on cellular and biochemical studies, we know that not
all PCBs are the same and that while some are quite
hazardous, others are relatively harmless," he say~.
To date, laboratory tests on animal cells have shown that
some kinds of PCBs are highly toxic, while others are not
toxic at all. But in order to gauge an individual's exposure
to the ~, scientists tradi tionally have counted all
the PCBs pz:esent, treating them as if they each had the same
effects.
"This is a poor way to assess the toxicity of a material,"
ElllDett says. In a continuing study, he is determining which
individual PCBs seem to be most toxic to man. .
In add.t tion, we subDi t that the li terature does not establish
that PCBs ate toxic to non-buman life in the doses to which an
animal might be exposed in the Re-Solve environment.
There simply is no credible evidence that PCB exposure in the
environment has or will cause any toxic effect to any animal,
including man, whether through direct contact or via the food
cbaiD. 'l!w analyses that formed the basis for the ban of PCBs
lid the establishm8Dt. of the ~ Tolerance Level of PCBs were
mainly laboratory experi_nts with PCBs of a tyPe that are not
nec:e8aarily those found in the environment at all, and certainly
not in the quantities that are found in the environment.
...
EPA Response:
A detailed toxicity profile for PCBs is provided in Appendix A of
the PRE and a detailed environmental toxicity profile is provided
in Appendix B. These profiles discuss the range of toxicity
~.
..,: :
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. . .
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36
information available on PCBs. Although there is, and
undoubtedly will continue to be, some disagreement over the
_potential human health and environmental effects of each congener
in the PCB mixture, EPA has developed an approach for evaluating
the potential human health risks associated with exposure to PCB
mixtures which relies on the use of cancer potency factors.
The ambient water quality criteria for PCBs (0.014 ppb) is below'
the CLP detection limits for PCBs (0.5 and 1 ppb), and therefore
the only way to assess this pathway was through mcdeling. In
Section 8.6, the uncertainties in the partitioning mcdel applied
were clearly discussed. However, this mcdel was considered .
adequate for evaluating the potential risks to freshwater aquatic
life.
B. PRP caR!2ft'S (If 'DIE rs Me) P&I~ AL'1'BINM'IVB
1. Misapplication of AMRs
COIIIDent:
The EPA misapplies SMA's requirement that "Applicable or Relevant
and Appropriate Environmental and Public Health Requirements"
(ARMs) be met at the site. The proper role for AMRs is in
developing the appropriate level of cleanup, not in determining the
suitability of various technologies to meet the cleanup level. As
discussed in the cODlllents submitted by the Generators CODIIIittee on
May 21, 1987, the AMRs relevant and appropriate to the Re-Solve
site are the interim status closure standards for surface
impoundments and land treatment facilities prClllUlgated under RCRA.
The site should therefore be closed under interim status rules.
EPA Response:
The Coami ttee appears to have some misperceptions about the proper
role of ARAR8 in the remedy selection process.
Once SPA has developed remedial action alternatives for a site, it
identifie8 the appropriate action - specific AMRs for each
alternatives. Each alternative is then evaluated by the remedy
selection criteria set forth in CERCLA Section 121, and EPA selects
" ..:
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37
. .
a remedy that best meets all of the criteria. In contrast, the mere
existence of potential action - specific ARARs, such as those for
landfill closure, do not determine the selection of remedy.
Further, the Conmi ttee indicates that the proper ARARs for the
Re-Solve sites are the 40 CFR Part 265 requirements for closure of
an interim status land disposal facility. EPA has made it clear
that the 40 CFR Part 265 interim status regulations will generally
not be applicable or relevant and appropriate to CERCLA response
actions. 'Ihis is explained in the 1985 National Oil and Hazardous
Substances Pollution Contingency Plan (NCP), 50, Fed. Reg. 47912 at
47918, November 20, 1985. 'Ihe NCP preamble states that although the
Subtitle C regulations differ according to whether a hazardous waste
facili ty has a ROA permit or is in interim statuS, CERCLA remedies
will,nonetheless have to comply with th, more stringent Part 264
requirements for permitted facilities.
'Ihe RCRA part 265 "interim status" standards were enacted to be
broadly applicable to large numbers of facilities and vast amounts
of hazardous waste. 'Ihey were designed to be bare minimum standards
so that the Aqency could concentrate on developing more stringent
technical based final (permitting) standards. In promulgating the
part 265 requirements, the Aqency stated that the interim standards
are not the final answer to the long-term environmental problems
caused by hazardous waste disposal. Nevertheless, EPA felt that
through the use of generally applicable requirements (i.e. manifest
system, recordk~nq, reporting, closure, water analysis, training,
inspection and continqency plan requirements) EPA would begin to
bring under control. environmentally disastrous practices. (F.R.
Vol. 45, No. 98, May 1980, p. 33157).
EPA believes that, in determining AMRa at CERCLA si tes, the RCRA
Part 264 standards should be used. 'Ihe Part 264 standards were
designed to be the final (permitting) standards that should be
attained by all facilities within a reasonable time frame. 'Ihe Part
264 standards represent the ultimate RCRA compliance standards and
are consistent with C!RCLA's goals of long-term protection of public
health and welfare and the environment (F.R. vol. 40, No. 224,
November 20, 1985, p. 47918).
The past waste disposal practices at the Re-Solve site were not
perfor.med according to RCRA design and operational requirements for
any type of facility. 'Ihe RCRA regulations define disposal as the
discharge, deposit, injection, dumping, spilling, leaking or placing
of any solid waste or hazardous waste into or on any land or water
so that such solid waste or hazardous waste or constituent thereof
may enter the environment or be emitted into the air or discharged
into any waters, including ground waters. A disposal facility in
RCRA is defined as a facUi ty in which hazardous waste is
. .
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. <
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38
. .
intentionally pla.ced into or on any land or water, and at which
waste will remain after closure. EPA believes tha~ the pa~t
disposal activities at Re-Solve constitute land disposal, and the
actual disposal unit employed at Re-Solve closely resembles the
definition of a surface impoundment. EPA believes, however, that
only the Agency has discretion to determdne which RCRA requirements
are relevant and appropriate on a site-specific basis.
The Comadttee also stated in their comments subadtted on May 21,
1987, that the "application of the i~terim status landfill closure
standard appears consistent with, and indeed mandated by, the
criteria of SARA Section 121". However, Section 121 of CERCLA does
not mandate compliance with any particular set of ARARs. Instead,
Section l2l(b)(1) articulates a preference for the selection of
remedial actions in which treatment pe~ently and significantly
reduces the volume, toxicity or mobility of hazardous substances.,
In assessing various pe~ent solutions, EPA must specifically
address the long-term effectiveness of the different alternatives.
EPA shall, at a minimum, take into account the Section 12l(b)(A-G)
factors.
Congress prescribes that in choosing its final remedy, £PA must
select a remedial action that uses permanent solutions and
alternative treatment technologies or resource recovery technologies
to the maximum extent practicable.
Region I believes that the Section l21(b) factors are utilized in
the evaluation in the Re-Solve rs and that the long-term
effectiveness of land disposal would not be adequately protective at
the Re-Solve site nor does it meet the statutory preference for
treatment. The Alternatives Evaluation Section of the ROD includes
a SUlllDary of how the Section 121(b) factors were evaluated in the
FS. .
2. Residential Land Use
CODIDent:
,-
'D18 rs and Preferred Alternative are based on the aSSUlDption that
th8 lite must be returned to a condition suitable for unrestricted
r..idential developDent.' SUch an assumption is overly conservative
and not reasonable. It is also inconsistent with the RCRA closure
standards which are the ARARs for the site. Other land uses (e. g.
conservation land) are more appropriate and consistent with both the
provisions of SARA, RCM and existing land use.
EPA Response:
') ,
EPA'S use of a conservative exposure scenario which assume~ on-site
exposure, including possible dermal contact wi th subsequent
absorption and ingestion by children, is well founded in £PA's
.'
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39
Office of Research and Development's (ROD) May, 1986 guidance on PCB
advisory levels, "Developnentof Advisory Levels for Polychlorinated
Biphenyls Cleanup". This guidance document constitutes an advisory
that is to be considered in determining the appropriate extent of
cleanup at CERCLA sites. EPA notes that it provided a partial list
of such "to be considered (TBC)" documents as an Appendix to the
preamble of the 1985 NCP (see 50 F.R. 47946). According to the ROD
advisory level guidance, it is entirely appropriate" to consider a
plausible maximum case that includes the "possibility of direct human
exposure to PCBs present at the site.
", 0
.'
",
FUrther, there is DO continuing industrial presence at or in the
vicinity of the site. The site itself is zoned for single family
residential and agricultural uses. The area surrounding the site,
als~ zoaed single family residential, is undergoing rapid
developll8llt. '111ere are two residences located wi thin 150 yards of
the site and eight wi thin a quarter ~le. A 7G-uni t residential
developuent is being constructed one-and-one-half miles south of the
site. "
EPA believes that there is a potential for the site, and surrounding
property, to be developed in the future despi te its previous use.
Recently, the owner of the property adjacent to the site along North
"Blxville Road initiated the perm! tting procedures for placement of a
residence on the property. MD~e iJaportantly, the land appears to be
in current use by the owner. A trailer was" recently observed on the
property, indicating that a person is temporarily residing there.
3. Institutional Controls
COIIID8nt:
without ~~, "nAtion or discussion, the rs fails to address or
consider institutional controls (e.g. deed restrictions) in
conjunction with other methods as a way of limiting and controlling
site use. SUch controls can be an effective mechanism for ensuring
attainment of cleanup objectives and should be considered. These
controls are also a requirement of RCRA interim status closure
EUles.
SPA Respcnse:
I!:PA believes that the selected remedy outlined in the ROD will meet
C!RCLA's preference for pe~ence and treatment and that the intent
of the RCRA closure requirements will be met by the treatment of PCB
contaminated soils and sediments and ground water treatment.
Section 121(b) of CERCLA states that the selection of a remedial
action be protective of human health and the environment, be cost
effective, and utilize pe~ent solutions and alternative treatment
technologies. EPA does not believe that limdts on site access and
. ,
-"
-,.- : .~. l . -
" "
0"
.. '."
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40
the use of institutional controls are pe~ent remedies to protect
human health and the environment.
FU~ther, EPA believes that the congressional directives in CERCLA
discourage the use of institutional controls when such controls are
not used in conjunction wi th a remedy that permanently and
significantly reduces the volume, toxicity and mobility of hazardous
substances, pollutants and ,contaminants. .
EPA does consider that institutional controls. may be appropriate
under certain circumstances. one such circumstance is present at
the Re-Sol ve si te. PCBs are present in the saturated zone soil
matrix and resulttnt concentrations in on-site ground water are in
excess of the 10- cancer risk level for the cClllpOUnd. EPA has
deter.mined that it is technically infeasible to restore the ground
water wi thin the waste management boundary. 'Ibis will necessitate
the use of institutional. controls. (i.e. ground water use
restrictions) for the area within the waste management boundary.
7he decision to use insti tutional controls for ground water was
arrived at follcwinq an analysis of the technical feasibility of
restoring ground water on site. 'l11e Agency does not consider
institutional controls appropriate ~r the entire site remediation,
since institutional controls alone will not satisfy the requirements
of Section 121.
4. Potential Risks of Preferred Alternative
COIIIIIent:
'Ibe remedial activities associated with the Preferred Alternative
contain several elements (e.g. wetlands destruction, on site'
incineration) that introduce new human health. and environ.ntal
risks. 'Ibese new risks have not been evaluated or caapared to those
of other alternatives.
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EPA Response:
'Ibe Agency's analysis of the short-term risks associated with the
implementation of the preferred alternative indicates that all of
the.. risks can be satisfactorily controlled. Additionally, any
short-term ri.ks appear heavily outweighed by the long-term
effectiveness and permanence the remedy would offer.
FUrthermore, the final remedy selected for the site will be
protective of human health and the environment, will be
cost-effective, and will utilize permanent solutions and alternative
treatment technologies to the maximum extent practicable and will
attain Federal and State ARARs. Remedies that are not selected will
be ruled out based on the evaluation criteria, not the short-term
risks associated with implementation of the' remedy. '
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If incineration is iricluded as a component of the selected remedy,
!fA will conduct a trial burn on site to determine if the
incinerator achieves' the requi rements of TSCA and RCRA. TSCA
requires that a selected incineration system must demonstrate a
99.9999 percent destruction and removal efficiency (DRE) of PCBs.
Nevertheless, air emissions from the incinerator stack would be
monitored during operation. If air emission levels exceed the
monitoring parameters established during the trial burn, the unit
will be shut down, thereby minimizing, any short-ter.m risks to
on-site workers and nearby residents.
At the Re-Solve site, EPA expects the air emissions from an
incinerator to attain all Federal and State ARARS. This is
primarily because the metal content in on-site soils is low,
especially the metals that tend to vaporize (Le, mercury and lead).
EPA believes that by virtue of the TSCA and RCRA requirements, the
potential risks posed by incineration are mini~l. Therefore,
incineration could be chosen as the primary treatment technology
without a complete reevaluation of all other appropriate
alternatives.
As .entioned previously, and contrary to what is stated on page
4-49, paragraph 4 of the FS, the heavy metal content in the Re-SOI ve
soils is low. ntis statement is supported by the data obtained from
the soil boring ptoqram conducted as part of the Supplemental RI.
Because the potential fo~ deli sting the ash Will depend on the heavy
metal content, EPA does not anticipate that there will be a problem
with delisting these residuals. For this reason, !PA's cost
estimate for incineration assumed that the treated soils would be
delisted and placed back on site.
If, for some reason, the treated soils could not be delisted, the
cost for incineration would increase. However, this would also be
true for other source control alternatives which involve the
deli sting of ueated soils and plaa!llel1t back on-si te.
5. 1 ppm PCB Criterion
c,..."t:
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'b cleanup cirterion of 1 ppD PCB, a~lied to wetlands and stream
sed1mlmts, is not explained and apparently has no fir.m scientific
basis. Consequently there is no firm basis for the extent of the
actian ptaposed by the P~eferred Alternative in the wetlands and
unn2IIII8d tributary. In addition, given the recent findings in the
New Bedford Health Study, it is apparent that selective capping of
the sediments in the unnamed tributary and banning fish consumption
would accomplish the same public health goa~s with less disruption.
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EPA Response:
Three- routes of exposure to PCBs in sediments were considered in the
development of cleanup criteria for sediments near the Re-solve
site. The exposure pathways examined were: first, direct contact
between benthic organisms and PCBs in sedimer1ts; second, exposure of
aquatic organisms in the water column to PCBs emdtted into the. water
from the sediments; and third, the exposure of predators, including
terrestrial organisms, to PCBs that have bioaccumulated through food
chains to higher trophic levels. The results of the analysis on
these three pathways of exposure are presented in Section VI of the
Ea).
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In selecting the PCB sediment cleanup level for the site, EPA
considered the following factors: the range of PCB sediment
concentrations (0.13 ppI1 to 2.5 ppa) associated with adverse impacts
to benthic organisms; location and concentration of PCB .
contamination; and adverse environmental impacts. Based on an
evaluation of these factors, EPA selected a cleanup level of 1 ppI1
for PCB contaminated sediments located in the wetlands north of the
site and the wmamed tributary.
EPA evaluated sediment capping as an alternative in the rs for the
Re-SOlve site. This alternative was screened out because of its
questionable effectiveness. The structural integrity of a cap is
unlikely to be maintained over tim due to soil expansion, settling
and erosion which may, in turn, result in the release of
contaminants.
6. Misapplication of "Permanent" Remedies
.,
Coament:
First, the FS incorrectly applies the SARA preference for selection
of sCH:alled "permanent" remedies to the evaluation of "permanent"
remedies. Second, the FS applies an i~roperly narrow definition of
"perDl2ll\ent8 remedy, incorrectly equating a "permanent" remedy to
only those that iDlDediately destroy hazardous consti tuents. As a
relUlt, the rs incorrectly eliminates from detailed consideration
theM alternatives, such as capping with ground-water renovation,
which permanently reduce' the mebili ty and volume of hazardous
substance. and which are mere cost-effective than the alternatives
ccna1dered by I!:PA.
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I!:PA Response:
Section 121(b)(1) of SARA states that the "remedial actions in which
treatment which permanently and significantly reduces the volume,
toxici ty or mebili ty of the hazardous substances, pollutants and
contaminants as a principal element are to be preferred over
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remedial actions not involving such treatment." It is evident that
there is a statutory preference for treatment and that the u~e of
treatment technologies (including destruction) or resource recovery
technologies is one way of achieving permanence. Conversely~
capping is not a permanent remedy nor does it involve treatment as a
principal element.
Capping merely separates waste from surface contact with humans,
. animals, and plants. Capping may slow the mobility of hazardous
substances, but it does not reduce the volume of hazardous substance
(except for leachate), nor does it reduce the toxicity of hazardous
waste.
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the site-specific waste than other treatment technologies. EPA
gathered information from outside the Agency and determined that
bioremediation is less developed as a technology than
deChlorination. Experts in the field (Camp Dresser McKee - COM)
that are currently running either bench-scale or pilot-scale
bioremediation studies info~ EPA that while the results from
bioremediation are promising, the technology is far from being
implementable in the field. EPA received estimates indicating that
it may take more than 5 years to be able to implement bioremediation
in ~e field. In addition, in-situ bioremediation below a depth of
one to two feet has shown little prcadse to date in the bench-scale
and pilot-scale studies. The remedy at the Re-Solve site will
require excavation to approximately five feet (see also response to
comment Ill). .
. 9. Soil Excavation Volumes
Comment:
No explanation or backup is provided to show what volumes of soils
would be excavated. The location of PCBs in soil across the site
have already been shown to be plotted incorrectly in the RI. If the
limi ts of contamination are the same as those shown in the RI, the
volume estimates used in the FS are not accurate and the cost
estimates developed are also not correct.
EPA Response:
In a letter to EPA dated JUly 14, 1987, the Comadttee's technical
contractor, ERr, requested additional information regarding the
Re-SOlve draft Feasibility Study. The following information was
requested:
cost and design data associated with the caps included in
alternatives SC-7a and SC-7b.
backup information for costs presented for carbon usage wi th the
water treatment; and .
lite plana or descriptions outlining the excavation limits
pr8unted in the preferred alternative document.
SPA provided EaT with such information in a letter dated July 23,
1987, one week before the close of the public comment period. EPA
believes that EaT had adequate time to CCIIIIIent on this information
during the comment period and an opportuni ty to sul:mi t supplementary
comments on this matter after the close of the public comment is not
justified.
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10. wetlands Restoration
CODIDent: .
The FS and Preferred Alternative assume that destruction of the
existing wetlands is warranted. However, eventual restoration of
the wetlands may not be feasib~e and, if feasible, is likely to be
less successful and mere costly than estimated in the FS.
EPA Response:
Excavation in the wetland north of the ii te and the unnamed
tributary will result in unavoidable impacts and disturbance to
wetland resource areas. Such impacts may include the destruction of
vege~ation, the loss of indigenous species and the migration of PCBs
downstream.
All e~cavation activities would be conducted during dry weather
periods and excavated areas would be isolated by means of erosion
and sedimentation control devices to limit the resuspension and
downstream transport of contaminated material. Downstream
moni to ring should also be conducted during excavation. EPA
considers that these measures will adequately mitigate any potential
risks posed by downstream migration of PCB contaminated sediments.
In its preferred al ternati ve, EPA did not assume that wetland
r.noration could be achieved by simply backfilling the excavation
to its original elevation and then allowing revegetation to occur
naturally. In fact, upon completion of the remedial activities in
the wetland areas, a wetland restoration program would be
implemented. Altered wetland areas would be restored to their prior
condition. This program would identi~ the factors which are" key to
a successful restoration of the altered wetland. Factors would
include, bit not necessarily be lim! ted to, replacing and regarding
hydric soils, provisions for ~ic control and provisions for
vegetative reestablishment, including transplanting, seeding or some
combination thereof.
Cost estimates for the wetlands restoration program were based on
estimates solid. ted fraa vendors and the cost of conducting similar
won in the Region.
FUrther, the reference to Sweeden's ~ is <:oq)letely irrelevant,
taken out of context and has no bearing on the case at. hand.
11. Dechlorination and Emerging Technologies
CODIDent:
The discussions of the dechlorination technology in the rs and the
Preferred Alternative do not adequately address the .technological
uncertainty of application of a full-scale unit to soils containing
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PCBs. The cost estimates associated with this application appear
unrealistically low. Also, other emerging technologies (e.g.,
bieremediation) are as well developed technologically as
dechlorination and may be less costly. Consequently, more
consideration should have been given to these in the FS evaluation,
and pilot studies of these technologies should be included as part
of the Preferred Alternative.
EPA Response:
The uncertainties of the operation of the dechlorination technology
on a full-scale level is discussed in the reliability and
implementability/constructability sections on page 4-69 of the
Feasibility Study. In addition, Figure 4-6 in the FS describes and
presents the development history of this technology. Further
analysis of the implementability of this technology at the Re-SOlve
site is presented in the Alternatives Evaluation section of the ROD.
The cost estimates presented in the Preferred Alternative and the FS
were based on information provided by Galson ResearCh Corporation,
the only vendor to date that is developing this technology for
treatment of soils. Furthe~re, contingencies were added to the
cost estimates to account for uncertainties associated with
implementabili ty of this technology on a full-scale level. Cost
estimates will be revised based on information and data obtained
from the pilot study.
Sioremediation technoloqie" were evaluated in the FS and screened
out because the uncertainties associated with these "emerging"
technologies were greater than dechlorination and other innovative
technologies. The problems associated with bioremediation are:
1. Maintenance of the proper environment for the micro-organism
populations ;
2.
High energy requirement to break down large complex molecules
such as PCBs. This translates into longer retention times to
complete the reaction;
3. Without agitation provided by a reactor, mass transfer is
greatly reduced, thus reducing the speed and effectiveness of
the reaction;
4. variable soil conditions of the site may result in inconsistent
flushing, thereby limiting direct contact between
micro-organisms and contaminants (PCBs), and;
s.
If bioremediation was implemented using landfarmdng technique,
large areas of land would be needed to set up and maintain these
plots. As stated in the FS and the ROD, the land surrounding
the Re-SOlve site is predominantly wetland resource areas., thus,
limiting the implementability of certain technologies requiring
large areas of land, including bioremediation.
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Further, the deep penetration of PCBs in the vicinity of 5B-25,
makes it increasi~gly difficult to maintain an environment suitable
for bioremediation (i.e. adequate supply of oxygen, nitrogen and/or
methane) . .
"
If dechlorination does not prove to be implementable at the Re-50lve
site, EPA does not consider it appropriate to evaluate a less
developed and less implementable technology, such as bioremediation.
Rather, the Agency will evaluate' a technology that is further along
in the developmental process so that cleanup at the site can be
initiated in a timely manner.
12. Cost Effectiveness
COIIIDIent:
While cost estimates are provided in the FS, there is not specific
discussion or apparent consideration of cost-effectiveness in either
the FS or for the Preferred Alternative as required by the National
Contingency Plan. Documentation is needed to indicate how EPA
considered cost-effectiveness in evaluating the various alternatives
and arriving at the Preferred Alternative.
EPA Response:
The Aqency's first statutory obligation is to select a remedy that
meets the requirements of CERCLA as amended' by SARA. If two
alternatives are detemine to be equally effective in meeting the
statutory requirements, EPA will select the least costly remedy. A
discussion on cost-effectiveness is presented in Section VI(B) of
the ROD.
13. Costs
Call1lent:
The costs of the Preferred Alternative are probably substantially
underestimated:
Wetlands restoration (if achievable) will take mere effort and
coat JIIOre than estimated by EPA.
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Ground water renovation will take an estimated 40 years not 10
years, increasing costs from $8.7 million to $11.4 million.
SOil dechlorination will be mere costly for a full-scale unit
than estimated by the supplier (and EPA) on the basis of pilot
studies at other locations.
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Knowing the actual potential costs of remediation (not just relative
costs) is important to a fair evaluation of alternatives and
selection of a Preferred Alternative.
EPA Response:
The Comndttee's comments on the costs for wetlands restoration and
dechlorination were responded to by the Agency in responses number
ten (10) and eleven (11) respectively. The Comndttee's comment on
ground water renovation is responded to in response number fifteen
(15), Ground water.
14. Disorganized and Confusing Cost Information
CODIIW!nt:
'lbe PRPs callDented that the FS contained disorganized confusing and
inaccurate cost information.
EPA Response:
EPA acknowledges that some of the costs ci ted in the Feasibili ty .
Study have scae mathematical errors. 'lbese errors have been
corrected and the new costs (i.e. MOM-2C and MOM-4) are presented in
the Alternatives Evaluation Section of the R;X). .
15. Ground water
Coaaent:
'b cc.ittee raised several concerns about the application and
coordination of 118thodoloqies and techniques used to predict the
rate 'and effectiveness of ground-water remediation. 'lbe CClllDittee
CCI8I8nted that the rs greatly underestimated the time requi red to
re.tore the aquifer.
EPA Response:
EPA conducted an analysis of the flushing rate and rate of
restoration of ground water, assuming excavation of a known volume of
VOC-contuU.nated on-site soils and using an experimentally-derived
leaching rate constant, to determine the estimated time period
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necessary to achieve .the target remediation level (lxlO-5 cancer.
risk level) at all points on the waste management boundary. (Refer
to Section IV B of the Re-Solve Record of Decision for more detail).
This analysis is presented in a document entitled "Re-Solve Aquifer
Flushing Technical Memo," (Technical Memo) which is included as part
of the Admdnistrative Record.
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Four separate models were used in the analysis to derive the aquifer
flushing rate and the rate of restoration of the ground water. A
geohydrologic model was used to obtain the maximum pumping rate and
flushing rate for the aquifer. Based on this modeling effort, EPA
estimated a pumping rate of 40 gallons per minute which translates
into 1.6 aquifer flushes. per year.
A second model, a fate and transport model, was used to simulate
ground-water extraction at the Re-Solve site. This is an iterative
technique for which each day, the model calculates the mass and
concentration of contaminants remaining in ground water as a
function of the mass of contaminants removed from ground water due
to pumping, and the mass of contaminants entering the ground water
due to leaching from the source soils.
The model assumes excavation of known quanti ties of PC8-contaminated
soil. As indicated in the Supplemental RI, the areal extent of PCB
contamination and VOC contamination in on-si te soils is similar.
'rhus, excavation of PCB-contaminated soUs in the unsaturated zone
(22,500 cy) will also result in the reduction of the mass of VOCs
which are acting as a source of ground-water contamination. Excava-
tion of soils contaminated with PCBs and VOCs in the unsaturated
zone above the seasonal low ground water table (approximated to be
elevation 85 feet) will result in attainment of the target re!tledia-
tion level wi thin 10 years. In contrast, if the source soils in the
unsaturated zone go untreated, EPA estimates that aquifer
restoration would take approximately 20 years.
Removal of the mass of VOC source material in the unsaturated zone
will thereby reduce the quantity of contaminants available for
long-term desorption frcm the soil matrix into ground water. The
rate of restoration of ground water, presented in ROD and the
Technical Memo, supercede preliminary estimates developed from the
equilibrium partitioning coefficient.
'l!Je leachinq rate constant was derived experimentally through the
conduct of a laboratory colUD1 leaching study (as presented in
Appendices B and D of the Re-SOlve FS). This leaching rate was used
in the mathematical model to project the duration of the puq> and
treat system. A sensitivity analysis was also done on the leaching
rate ~tant to determine how the model is affected by this
parameter. Results indicated that this model was very sensitive to
this parameter and a change in this leaching rate constant by as
little as a factor of two or three can dramatically change the
predicted time of cleanup.
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A third model developed for the site, a ground-water flow model, was
used to estimate the number of aquifer volumes necessary to flush
contaminants and the associated treatment time to aehieve the target
r~iation level for TCE and PeE in a source well placed on site in
the center of the plume. TCE and PCE respectively compose 27.9\ and
12.3\ of the total VOC concentration in the contaminant plume. PCE,
though, was used as the indicator compound for the analysis because
its lower vapor pressure and so~ubility cQlllpared to other indicator
compounds is such that its natural transport away fran the source
area is slower than other volatile organics.
A final model, the Soil Contaminant Evaluation Methodoloqy (SOEEl1)
was used to determine the allowable concentration of PC!: in a source
well located in the center of the plume, given that the target
remediation level for PeE at the point of compliance (i.e. the waste
manaqement boundary) is 5 ppb.
Based on the results of these modeling efforts, an estimated 16
aquifer volumes will have to be pumped and treated over a pefiod of
10 years to attain the target remediation level (i.e., 1xlO- cancer
risk level) at the point of compliance.
In regard to an abbreviated aquifer remediation time period due to
hydrolys,is chemical degradation of ~ present at the Re-Solve
si te, Appendix B of the FS states "hydrolysis will not be a major
factor contributing to the degradation of the contaminants at the
Re-SOlve site since the contamination is largely CallpOsed of the
slower degrading compounds". In addition, dUe to the time period
required for aquifer remediation, hydrolysis will not be a
significant factor in reducing the rate of remediation.
Overburden and Bedrock wells
Wells installed for the pump and treat system will serve to extract
ground water for treatment, and monitor elevations and gradients of
ground water. 'lhree bedrock wells will be installed at suspected
high contaminant zones in the bedrock. Initially, these bedrock
wells will act aa monitoring wells to determine contaminant levels
in the bedrock and vertical hydraulic gradients between the bedrock
and the overburden. If upward vertical hydraulic gradients and
decreases in ground-water contamination in the bedrock are not
exhibi ted during an extended time period operation of the overburden
pullping system, then the bedrock men! to ring wells will be pumped at
low vol\88s in order to remediate the bedrock aquifer. .'
Private Wells
Regarding private wells in the vicini ty of the Re-Sol ve site, EPA
:.. agrees that the statement on page 3-34 of the FS is not correct.
The residential well sampling program indicated that the current
quality of drinking water in residential wells located in the
vicinity of the Re-Solve site has not been noticeably affected by
contaminar&ts originating fran the site.
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RB8INDG PUBLIC CCH:!:RNS
There were several issues and concerns raised during the
responsiveness summary that EPA will address during the remedial
design and remedial action. These issues and concerns include the
following:
(l)
Contamination of Fish and Wildlife: Residents continue to be
concerned about the quality of fish and wildlife in areas around
the Re-Solve site. As stated in the ROD, fish will be sampled at
downgradient stations during the remedial action.
Contamination of Residential Wells: Residents continue to be
concerned about the contamination of private drinking water wells
around the Re-Solve site. During the remedial action, select
downgradient monitoring wells and residential wells will be
sampled to assess the efficiency of the ground water restoration
program.
(2)
(3)
provision of Remedial Design Information: '1'here is considerable
concern that new information gathered prior to the remedial
action be available for public review and coaaent. Particular
areas of interest are: results of the dechlorination pilot
project; plans for restoring wetland areas following excavation;
additional ground water remediation analysis (e.g. soil column
experiments); and other infor8ation, such as cost estimates, that
8Y bit ejenetated during the remedial design. EPA will c.wntinue
to meet periodically with interested parties during the remedial
design to discuss new information and design plans. In additon,
an informational public meeting will be held when the design is
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~A
CXl9UaTY RELM'ICH; ACTIVITIES a:HU::'mD AT 'mE RE-SOLVE SITE
community relations activities conducted at the Re-Solve site to date have
included:
. EPA prepared a community relations plan in July 1982 that outlined
community relations activities to be conducted during the RI/FS;
EPA held a public meeting with town officials in June 1983 to
discuss the on-site RI/FS and its preferred alternative for the
site;
In response to public comments, !PA modified its preferred
alternative. The selected source control remedial action entailed
excavation, treatment, and disposal of PCB-contaminated soils and
sludges at an off-site disposal facility and encapsulation of the
site;
EPA held a public meeting at the 95' design phase to discuss the
source control remedial action and to sol~cit public comment;
During construction of the source control remenial action, EPA
held weekly press conferences at the site;
EPA established information repositories in the site community;
In August 1986, !PA, filA D~I!:, and the Massachusetts Department of
Bea..lth po8ted warning signs around the Copicut River warning
a~inst the consumption of American eels;.
In March 1987, !PA held a public meeting at the Southworth Library
in Dartmouth to discuss the results of the Supplemental Remedial
Investigation;
During the develOpDent of the rs, the Westport River Defense Fund
and a local citizens group, Precinct Qte North Dartmouth
(P.a.N.D.) worked cooperatively to form a Citizen's Advisory
Cc:IIaittee (CAe) for the site. EPA and MA D~I!: assisted in the
organization of the CAe and met with the group during the remedial
alternative selection process;
In June 1987, !PA held a public meeting at the Dartmouth Town Hall
to discuss the Feasibility Study Report and the preferred
alternative;
In July 1987, EPA held a public hearing at the Dartmouth Town Hall
to accept oral comments on the Feasibility Study and the preferred
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alternative and td answer additional questions. Transcripts of
this hearing are available at the EPA Region I office in Boston,
and at the information repositories located in the site community;
and;
In response to requests from the public, EPA allowed an extension
of the public cOJIIIIent period. The cOlllDent period lasted from June
11 until July 31, 1987.
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