United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R01-87/021
January 1387
SEP A
Superfund
Record of Decision
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TECHNICAL REPORT DATA
(Pleue nad Inltructions on the rellene befOl'e cOMpleting)
1. REPORT NO. 12. 3. RECIPIENT'S ACCESSION NO.
EPA/ROD/ROl-87/02l
.. TITLE AND SUBTITLE 5. REPORT DATE
SUPERFUND RECORD OF DECISION January 16, 1987
Ottati & Goss/Great Lakes, NH e. PERFORMING ORGANIZATION CODE
First Remedial Action - Final
7. AUTHORIS) 8. PERFORMING ORGANIZATION REPORT NO.
It. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM EL.EMENT NO.
". CONTRACT/GRAN1'NO.
12. SPONSORING AGENCY NAME AND ADDRESS 13. TYPE OF REPORT AND PERIOD COVERED
U.S. Environmental Protection Agency Final ROD ReDort
401 M Street, S.W. 1.. SPONSORING AGENCY CODE
washington, D.C. 20460 800/00
15. SUPPLEMENTARY NOTES
HI. ABSTRACT
The Ottati and Goss/Great Lakes Container Corporation site (O&G/GLCC) is located in
Kingston, New Hampshire west of Route 125. The study area for the RI/FS includes the
35-acre O&G/GLCC site, a marsh area east of Route 125 and Country Pond adjacent to the
marsh area. North Brook and South Brook drain the marsh at its interface with Country
Pond. From the late 1950s through 1967, Conway Barrel & Drum Company (CBD) owned the
site and performed drum reconditioning operations. The reconditioning operations
included caustic rinsing of drums & disposal of the rinse water in a dry well near South
Brook. As a result of State concerns regarding the proximity of the dry well to South
Brook and complaints of resulting South Brook and Country Pond pollution, CBD
established leaching pits in an area removed from South Brook. The State's Water Supply
and Pollution Control Commission (WSPCC) reported onsite runoff and seepage from the
leaching pits draining into South Brook and eventually into Country Pond. Reports
included fish kills in Country Pond, dying vegetation along South Brook, and skin
irritation of swimmers in Country Pond. In May 1973, International Mineral & Chemical
Corporation (IMC) purchased the drum and reconditioning pland and owned and operated it
until 1976. Beginning in 1978, heavy sludges (approximately thirty 55-gallon
drums/month) from the wash tank and drum drainings, as well as residues from incinerator
operations, were brought to the O&G site for processing. After the O&G operations
(See Attached Sheet)
17. - KEY WORes ANO DOCUMENT ANALYSIS
a. DESC'UPTOAS b.IDENTIFIERS/OPEN ENOED TERMS C. COSATI Field/Croup
Record of Decision
Ottati & Goss/Great Lakes, NH -
First Remedial Action - Final
Contaminated Media: gw, sw, soil, sediment
Key contaminants: VOCs, ABN, PCBS, pesticide 9,
metals, cyanide
18. DISTRI8UTION STATEMENT 11t. SECURITY CLASS IT/,is Report} 21. NO. OF PAGES
None 52
20. SECURITY CLASS ITliis pagel 22. PRICE
I None
!,. '01111 2220-1 (Re.. 4-")
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o
i
EPA/ROD/ROl-87/02l
Ottati & Goss/Great Lakes, NH
First Remedial Action - Final
16.
ABSTRACT (continued)
cea~ed in June 1979, the New Hampshire Bureau of Solid Waste Management
ordered the owners & operators of the site to remove the drums and cease
site operations. In September 1981, the O&G/GLCC site was placed on the
National Priorities List (NPL). Contamination has been identified both on-
and off-site in the ground water, surface water, and soil/sediment. The
primary contaminants of concern include: volatile organic compunds (VOCs),
acid and base/neutral compounds, PCBs, pesticides metals, and cyanide.
The selected remedial acton includes: excavation of approximately 5,000
cubic yards of PCB contaminated soil and sediments followed by destruction
of contaminants by incineration: aeration (low temperature thermal
stripping) approximately 14,000 cubic yards of contaminated soils:
installation of ground water extraction and treatment system with discharge
of treated ground water to upgradient ground water and possibly, to local
surface waters: site grading and disposal of contaminated GLCC building
materials: site cover: and installation of ground water and Country Pond
monitoring systems and drinking water surveillance program. The estimated
capital cost for this remedy is $8,592,500 with annual O&M costs of
$1,735,000.
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:
SITE DESCRIPTION AND SUMMARY
OF REMEDIAL ALTERNATIVE SELECTION FOR THE
0TTATI & GOSS/GREAT LAKES CONTAINER CORPORATION
SITE
Jan~ary 1~, 1981
US-EPA
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Site:
RECORD OF DECISION
REMEDIAL ALTERNATIVE SELECTION
Ottati & Goss!Great Lakes Container Corporation
Kin~ston, New Hampshire
Documents Reviewed
I am basing my decision concerning the appropriate remedial
alternative for the Ottati & Goss/Great Lakes Container Corporation
Site (O&G/GLCC Site) primarily on 'the following documents. A
substantial number of additional documents are included in the
administrative record as well.
1.
o&G/GLCC Remedial Investigation/Feasibility Study, Volumes
I-VII, August 1986, prepared by Gol~berg-Zoino and
Associates, Inc. - .
Summary of Remedial Alternative Selection.
2 .
3.
Co~munity Relations Responsiveness Summary.
4 .
December 1985 Opinion in United States, et ale v. Ottati
& Go s s, ! n c., eta 1
s.
Testimony and Exhibits introduced in United States,
. et-al. v .Ottati & Goss , Inc., e~. al
6.
Public Comments
7.
The comprehensive
and Liability Act
as amended by the
Act ot 19~6.
Environmental Response, Compensation,
of 1980, 42 U.S.C. 55 9601 !! !!3.'
Superfund Amendments and Reauthorization
8.
The National Oil and Hazardous Substances Pollution
Contingency Plan, 40 C.F.R. Part 300, November 20, 1985.
Description of Preferred Remedial Alternative
Excavation of approximately 5,000 cubic yards of PCB
contaminated soil and sediments followed by destruction of
contaminants by incineration.
Aeration (low temp~rature thermal stripp~ng) of approximately
14,000 cubic yards of contaminated soils.
Installation of grounnwater extraction and treatment system
with discharge of treated groundwater to upgradient ground-
water, and possibly, to local surface waters.
Site grading and disposal of contaminated GLCC building
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v:
Site Cove
Inst~llation of aroundwater Monitorina syste~, ~ri~kinq
water surveillance program, and Country Pond ~onitorinQ
s y stem. .
o
Op~rAtion and Maintenance
Maintenance will include lawn Mowinq of the qrass cover
system, clearinq obstructions from th~ site stormwater
,drainaqe systems, and rearadinq of the site as necessary.
Monitorinq will include samplinq and analysis of up~r~dient
and downoradient monitorinq wells: of surface waters incluoinq
Country pono: and of area private water sUPDly wells.
Declaration
Consistent with the Comprehensive Bnvironmental ResDonse, Com-
pensation, and Liability Act of 1980 (CERCLA), as amended by the
Superfund Amendments and Reauthorization Act of 1986 (SARA or the
1986 Act), and the National Oil and Hazardous Suhstances Pollution
Contingency Plan (NCP), 40 C.F.R Part 300. ! have determine~ that
at the O&G/GLCC Superfund Site, ,the selected remedial alternative
is cost-effective, consistent with a permanent remedy and provides
adequate protection of public health and welfare and the environment.
The State of New Hampshire has been consulted ann concurs with
the selected remedial alternative.
I have determined that the action beinq taken is consistent with
Section 121 of SARA and is appropriate when balanced aqainst the
availability of Trust Fund monies for use at other sites.
, The action will require oDeration and m~intenance activities to
ensure continued eff~cti"eness cd the remedial alternative as well
as to insure that the performance objectives meet applicable state
surface and groundwater quality criteria.
J/J'/v.
Date
.
, . I --, /
/ ,,-£""-/10',' -_L ~
Reqional Administrator
r:
--
--
The authority to siqn this. Record of Oecision under the 1986
Superfund Amendments has not yet been deleqated by President
Reaqan. This ROD will become effective upon my r~ceipt of.
such delegation.
, I
J i ,:. 'r. 7
Date
, ~, /'. , ,
)~' , ~'I..-/ C? <~ ~ol
Reqional Administrator
{,..7
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TAI3LE
OF
CONTENTS
Site
Location
De scr i pt ion. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
and
S~te History........
.................. ....................
Current
Site
........... ...........................
Statues.
Risk
Assessment.....
.............. ....... .................
Conta'!'\inants of
Concern.
............................. .
Exoosure
Pathways/Exposure
Populations..
..............
Risl(
C~aracterizatio~....
. ... ... ..... ....... ..........
Development of Alternatives.
. ...... ..... ..... .............
Initial
Screen i nil. . . . . . . . . . . . . ... .". . . . . . .
..................
Deta iled
Evaluation of
Alternatives..
.....................
~ecoTTUT1ent1ed
~lternativ'a.
..... .......................... I"
Source Control......
..... ............... ...... ........
Management
of
Migration
...................
Re'T\e1y.....
Rationale
for
Selection of
Alternative
EPA's
Its
Preferred
Legal
Re qui r erne n t es . . . . . . . . ... . . . . . . . . . . . . .
.............
Leqal
Requirements ApPlie1
to this Site...............
Operation
Ma i n tena nee. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
and
Scheoule.............
. ............... ..... ....... ...... ...
Com~unity Relation~....
. ............... .... ...............
Enforcement Analysis.~.....
. ..................... .........
Responsiveness
Summa!'v. .
....... ...... .............. .......
1
3
5
8
8
~
9
10
11
12
23
23
27
31
31
32
43
44
45
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Site
S.ite
Lo c us
Plan...
\1
FIGl1RES
Figu re
Pla~. . . . . . . . . . . . . 0 . . . . . . . . . . 0 . . . . . . . . . . . . . . . 0 . .1
. . . . . . . . .
of
Total
Distribution
Prof ile. . . . .
RCRA
Proposed
Cap
Identified
Site
Groundwater
Cove r
Areal
Extent
Areas
for
Treatment
. . . . . . . . . . . . . . . . . e 8 . . . . . . . . . . . . . . . . . . 2
Volatile
Organics...................3
. . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
of
Site
Ca p. . . . . . . . . . . . . . . . . . . . . . . . . 5
Source
Removal........~...............6
prof ile. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
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TAI:.~LE~
Ta!:>le
Sum~ary of Technology
Scree n i n~ . . - . . . . . . . . . . . . . . . . . . . . . . . .1
Llsting of Remedial Technologies
L~sting of Remedial Alternatives..........................2
Remedial Alternatives
Pas 5 i n~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pu~lic Health and Environmental Screening.
Remeoial Alternatives
pa s sing. . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Pu~lic Health and Environmental screen~~g
Recom~enoe~ Alternative Cost Summary......................5
Manage~ent of Migration
Recommendect Alternative Cost
SUmma ry ... . . . . . . . . . . . . . . . . . . . .6
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SITE DESCRI?TIO~ AND SUMMARY
Of RE~EDIAL ALTERNATIVE SELECTIO~ FOK THE
OT!~Tl & GUSs/GkEAT LAKES CO~TAINER CURPORATION SITE
SITE LOCATION AND DESCRIPTION
The ottati & Goss/Great Lakes Container Corpor.:!tion (O&G/GLCC)
site was placed on the National Priorities List on September, .
1981. The site is located immediately west of Route 125 in
Kingston, New Hampshire, as shown on Figure 1. The entire site,
depicted on Fiyure 2, consists of approximately 35 acres. The site
is bounded on its easterly side by Route 125 and is traversed by an
Exeter-H~~~ton Electric Company power line easement. Approximatp.ly
28 acres of the site are owned by the Senter Transportation Co.
(Senter) with the remaining 5.88-acre portion currently owned by
Great Lakes Container Cor~oration (GLCC). The GLCC property contains
a one-story cinder olock building. Sente~.~ransportation leased
an ap?roximately one-acre parcel in the southwestern ~ortion of
tne site to the Ottati & Goss, Inc. in 1978.
The site occupies an east-west trending topographic valley which orains
to the east toward a marsh ar~~ east. of Route 125. Site topographic
relief is on the order of 10 feet, decreasing from a ground surface
el~vation of a~~roximately 135 to 140 feet above mean sea level at its
westerly ed~e to approximately 125-130 feet just west of the Route 125
em~anKment .
Two ~rooks traverse the site to the nort~'and south. North. Brook
flows eastward near the northerly boundary of the site through
a culvert beneath Route 125 and into the marsh adjacent to Country
Pond. South Brook flows eastward near the southerly edge of the
site, through a culvert beneath Route 125 and into the marsh.
These brooks drain several marshy areas of seasonally ponded
surface water on-site.
The study area for the RI/FS includes the O&G/GLCC site, a marsh
area east of Route 125, and Country Pond adjacent to this marsh
area. The marsh is somewhat triangular in shape and wooded, with
an area of approximately 40 acres. Three small brooks were
ooserved draining the marsh at its interface with Country Pond,
the northern-most of which is North Brook.
The O&G/GLCC site is underlain by 20 to 50 feet of soil deposits
.consisting of fill, glacial outwash,. glacial ice contact deposits,
ana ylacial till. Fill.materials appear to be granular and to
locally contain buried drums and drum fragments. Outwash ann ice
contact deposits consisted of sands and, gravels'"and are considered
to comprise a relatively permeable overburden aquifer. Glacial
till underlyiny the aquifer, while relatively less permeable than
other unconsolidated deposits, was not observen in all borings
and is not considered very restrictive of groundwater flow between
the overburden aquifer and underlying bedrock. Bedrock, to the
depth investijated (30 to 40 feet below the bedrock/overburden
contact), ~as observed to consist of schist with pegmatite and
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~ranite intrusions. The schist was observed to be sligntly
weathered and slightly to m~derately fractured. The pegmatite and
granite encountered in the rock cores were observed to be fresh to
slightly weathered, and fractured to a similar degree as the sChist.
permeaoility of the oedrock was generally observed to be low to very
10w.
Bedrock topographic data contained in the Remedial Investigation/
Feasibility Study indicate that a r-shaped trough or depression
trending to the east underlies the site west of Route 125 with the
2 "forks" portion of the GLCC site. Available data suggest this
depression continues to the east of Route 125. A possible bedrock
high was observed in the north central portion of the marsh.
Groundwater within the overburden aquifer beneath the O&G/GLCC site
flows to the northeast across the site toward the topog'raphic low
ass~ciated with North Brook. Upon approaching North Brook, flow
becomes southeasterly. Overburden groundwater flow converge~ .
and flows under Route 125 at the.eastern edge of the site.
Southeasterly groundwater floW""contin-ues within the marsh area
east of Route 125 toward Country Pond.
On-site, where ice contact deposits predominate, the rate of
groundwater flow was estimated at approximately 60-240 feet per
year. In the marsh area, where )~ore permeable outwash deposits
preoominate, the rate of groundwater flo~ was estimated at .
approximately 110 to 330 feet per year.
.Both upward and downward hydraulic pressure gradients between the
bedrock and the overburden, as well as within the bedrock, were
oeserved at various locations around the site. The presence of
significant downward gradients in some areas, together with the
lack of a t.:ontinuous itTlperr.H:tat,l~ soil layer bet""een ovelobul-jen and
bedrock, indicates the potential for localized migration of
overburden aquifer contaminants into bedrock.
Groundwater is the present drinking water source in the study area.
Water is supplied by individual residential wells deriving water
from unconsolidated bedrock aquifers. To date, no residential well
contamination has been attributed to the site. There is presently
no state or municipal restriction of groundwater use in the vicinity
of the site. .
Groundwater, surface water, and soil/sediment contamination is
identified both on and off site. The major classes of compounds
detected include volatile organic compounds (VOCs), acid and
base/n~utral (A8N) extractable organic compounds, polychlorinated
bi~henyls (PCBs), and metals.
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.
~ /.~M"" ~
Gb\
LOCUS PLAN
o AG/GLCC SITE
KINGSTON,N.H.
0'
1000'
2000'
~o~~.
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CI"nER
nLOCK
BUllO,"G
.
4 rt
"
. "
, II
t
t
C.
ol
.
tI
en
..
. --~..._..- I
O' 150' 300' lOa'
SITE PLAN
0 IG/GLCe SITE
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SITE HI::;TURY
Portions of the site have been used for dru~ reconditioning
operatio~s and for disposal of hazardous materials since at least
the late 1950's. The following summary of site history and plant
operations is based on discussions with personnel from the U.S.
EPA, New Hampshire Water Supply and Pollution ContrQl Commission
(WSPCC), and the U.S. Department of Justice: depositions and
court testimony from ongoing litigation (United States, et ale
vs. ottati , Goss, Inc., et al.); and the Findings of Fact.
From the late 1950's through 1967, drum reconditioning operations
were performed on the present GLCC site by the Conway Barrel and
Drum Company (CBD), owned by Messrs. James and Daniel Conway.
Available information concerning site operations of the CBD is
limited. A State of New Hampshire Water Pollution Board (WPR)
memorandum dated September 28, 1961, indic~ted that the CBD was
estaolished in 1959 for the purpose of reconditioning drums.
WSPCC files indicate that reconditioning operations included
caustic rinsing of drums and .apparent disposal of the caustic.
rinse water in a dry well in the vicinity of South Brook. The
location of the dry well was not documente~.
As.a result of State concerns regarding the proximity of the dry
well to South ~rook and complaints of resulting South Brook and
Country Pond pollution, CBD established a "leaching pit" in an
arGa removed from South Brook. This pit is commonly referred to
as the "caustic lagoon" and was located on the property
a?~roximately 150 feet to the west of the existing cinder block
building. The approximate location of the former caustic lagoon
is shown on Figure 2.
A review of WSPCC files indicated numerous complaints against
caD by area residents. These complaints focused on on-site
runoif and seepaye froln leaching pits drainir.g into S~,Jt1. 3rook
and eventually into Country Pond. Complaints included reports 0:
fish kills in Country Pond, dying vegetation along South Brook,
an~ skin irritation of swimmers in Country Pond.
In 196i, r1essrs. Leroy Boudreaux and Daniel Conway formed the Kingston
Steel Drum Company (KSD) which continued site operations until 1973.
The KSD operations consisted of reconditioning both open head and
closed head drums.
For open head drums, residues were emptied into 55 gallon drums which
were reportedly hauled away from the site. Emptied drums were then
passed through an incinerator to burn off remaining residues and
subse~uently brou~ht into the plant for sand hlasting, dedenting, and
lining operations.
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Reconditionin~ operations for the closeo heao drums differed from
those for the open head drums. The closed head drums were pre-
flushed and then rinsed with a cau5tic rinse solution. The drums
were then washed in a dilute hydrochloric acid solution, sand
blasted, and dedented. Caustic rinse water was disposed of in
t~e previously described caustic lagoon located approximately 150
feet to the west of the cinder block builrting.
As described in a March 28, 1973 International Mineral and
Chemical Corporation (IMC: me~orandum, the caustic lagoon was a
barbell shaped pond averaging approximately 25 feet in width, 100
feet in length and 3 feet in depth. An oil layer 1-1/2 feet
thick was reported to cover the lagoon. According to the IMC
memorandum, in 1973 the caustic lagoon received approximately
4,000 gallons/day of caustic rinse water.
Another small pond, commonly referred to a.~. the "Kingston Swamp"
was described in the same 1973 IMC memorandum as being .generally
circular in shape, approximately lUO feet in diameter and 1 foot
deep. . The approximate forme~ location of the "Kingston Swam?~ is
shown .on Figure 2.
In May 1973, KSD was purchased by IMC, who owned and operated the
drum reconditioning plant from 1973 until 1976. With some
modifications, IMC continued riru~ reconditioning in a manner
similar to KSD, though apparently on a larger scale. Modifications
apparently included measures intended to reduce the potential for
pollution at the site. In the March 28, 1973 IMC memo, three
potential pollution sources were identified by IMC prior to its
purchase of the site. These included the caustic lagoon, th~
"Kin~ston Swamp", and spill water, including floor washings and
building rinse water from the north side of the plant which
eventually discharged into South arook. Water samples collected
in March 1973 by IMC indicated degraded water quality in the
ca~Ltic layoon, "Kin;s~cn Sw~~p", and or-~ite dr~~n~gA i~~o Sout~
Brook at Route 125.
Tne "Kingston Swamp" was reportedly backfilled in 1973 and the
caustic lagoon was backfilled in 1974. Oil separation equipment
was installed and IMC, and later GLCC, stored "deoiled" and
"oily" wastes from the closed head drum process in separate
on-site holding tanks.
Heavy sludge s (approxima.tely th irty 55-gallon drums per month)
from the wash tanks and drums drainings, as welY as residues
from incinerator operations, were brought to the O&G site for
"processing" beginning in 1978. After the O&G operations ceased,
in June 1979, GLCC continued processing these sludges on-site in
a manner similar to the O&G process. GLCC reconditioning
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. ,
~ '..", + . .. .'
. .
..' .., '--."
o
operations ceased in July 1980. A large number of drums were
reportedly removed by GLCC in 1981~
Between July and ~ecember 1984, IMC performed drum excavation and
removal operations at the GLCC site. These operations included
excavating large portions of the GLCC site where drum burial
was suspected based on previous test pit excavation~, geophysical
data, and court testimony. The O&G site was operated by Ottati
and Goss, Inc., Mr. Louis Ottati, and Mr. Wellington' Goss, from
March ~978 through June 1979. During this time, site operations'
consisted of "processing" hazardous materials brought to the
site in drums. This processing apparently involved emptying the
contents of the drum in the box of a dump truck and mixing the
wastes with sawdust and lime. The mixed waste and sawdust was
then placed in dumpsters and reportedly removed from the site.
'Material processed at the site allegedly included sludges from
the GLCC site. On July 1, 1979 the New Hampshire Bureau of Solid
Waste Management ordered the owners and operators of the O&G site
to remove the drums and cease site operations. Between December
1980 and July 1982, EPA processed and removed approximately 4000
drums of waste from the .O&G site. IMC, the owner and operator of
the KSD drum reconditioning plant from 1973 to 1976, performed
drum excavation and removal opera~ions between July and December
1984. All stockpiled contaminated soils were removed from the
site by'June 1985. The total volume of contaminated soils,
drums, and metal debris removed was approximately 12,800 tons.
However, results of the Remedial Investigation (RI) indicate that
additional drum fragments, crushed drums, and contaminated soil
remain on the site.
CURRENT SITE STATUS
GOldberg-Zoino & Associates (GZA), under contract with the New Hampshire
Water Supply and Pollution Control Commission, completed a Remedial
'Investigation/Feasibility Study (RI/FS) for the O&G/GLCC Site in
August 1986. Data collected in the RI and in previous studies
done by Ecology and Environment (E&E), under contract with EPA:
P.E. LaMoreaux and Associates (PELA), consultants to GLCC: Roy F.
Weston (RFW) , consultants to GLCC: and Camp, Dresser & McKee (CDM),
consultants to International Minerals and Chemical Corporation:
were used to describe the nature and extent of contamination.
Contamination sources, contaminant transport, environmental
receptors impacted and suspected risks posed by contaminants are
evaluated in the Remedial Investigation/Feasibility Study Report.
The following is a. brief summary of the types and concentrations
of contaminants detected in soil, sediment, groundwater, surface
water, and air.
o Soil
Elevated concentrations of VOCs, PCBs, ABNs, metals and cyanide
have been observed in on-site soils at numerous locations on one
or both of the O&G/GLCC portions of the site. At least four
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.--- - .- ---.-- .-
major VOC contamination (high of 870,000 ppb) source areas have
been identified1 the GLCC caustic lagoon area, the "Kingston
Swamp" area, an are~ immediately east of the cinder b10c~ bUilding
on the GLCC site, and the O&G site. Of the VO~s identified at t~e
O&G/GLCC site, four of the contaminants are orobable or known
carcinogens. They are: trichloroethylene, tetrachloroethylene,
1,2-dich1oroethane, and benzene. Samoling performed subsequent
to th~ IMC removal identified maximum concentrations of
trichloroethylene of 3,900 9pb and tetrachloroethylene o~
160,000 ppb in the vicinity of the caustic lagoon. A furt~er
discussion of these carcinogens is included in t~e ~anaqe~ent o~
',igration Remedy. Due to past waste dis~osal oractices at t~e
site, it is likely that additional localize~ contaminant ~ource
areas exist. The ob5ervation of buried 1rums in the uober 6
feet of soil at numerous locations indicates the ~otential.~or
concentrated w90int" sources for VO~s, and ~erha~s, other conta~inan~so
PC~s were observed in soils over a wide area o~ t~e site. The
highest PCB concentrations (143,OO~ ~ob) were observed in the
"Kingston Swamp" and caustic 1agoo~.areas~
ABN compounds (high of 19,000 ppb) were observed in on-site soils
at nu~erous locations in concentrations on the same order as
VOCs, although there is no apparent correlation in terms of
spatial distribution between ~B~s and VOCs. The mobility of ABNs
in groundwater or surface water is limited due to their ~ro~ensity
to absorb onto finegrained soil particles. ~any metals and
cyanide were observed at elevated concentrations in on-site soils~
highest concentrations were observed in areas of susoected ~ast
disposal activity. As with VOC contamination, past ~ractices at
the site suggest that additional, localized contaminant source
areas are likely present. Although both arsenic and nickel have
~een ~bserve1 at elevatej concen~rations in groundwater downgrad-
ient ot the site, arsenic concentrations in on-site soils did not
'exceed those observed at 9resumed background sam~ling ooints.
o Surface Water and Sedime"~-
The principal contaminants of concern trans~orted in sur~ace
waters in North and South Broo~s are dissolved vor::s P'1iqh total
VOC- concentration of 500 oDb) in surface waters and se~i~ents
(high total VOC concentration of 6,OO~ o~b) in the vicinity of
the North Brook inlet to Country ~ond. These VOC co~centrations
appear to be re1ate~ to uoward discharge of conta~inated
groundwater. Despite t~e oresence of VOCs in oond water and
sediments in the vicinity of the North aroo~ inlet, volatilization
and pond dispersion characteristics likely account for the lac~ of
detection of VOCs in other areas of the pond.
Also of concern is the a~~arent transport of PCB-contaminated
South Brook sediments into the marsh area, where uo to 14,000 Dob
of ~CBs has been reported by EPA, based on t~e results of samoling
performed in "ay 1980.
-------
,0 Groundwater
The groundwater contaminants of principal concern at the O&G/GLCC
site are VOCs, arsenic, and nickel, iron and manganese. ABNs
appear to be highly attenuated relative to VOCs. PCBs/pesticides
were net observed in groundwater downgradient of the site.
VOC groundwater contamination arises from numerous on-site source
areas, most notably the O&G site, the caustic lagoon area, the
"Kingston Swamp" area, and the area east of the GLCC cinder block
building. Total VOC concentrations in groundwater in these areas
generally have exceeded 10,000 ppb. The Court found the O&G plume
moves generally from southwest to northeast and then parallel to
North Brook and towards Route 125 and the marsh.
Individual contaminant plumes generated on-site would merge
due to converging groundwater flow. East of Route 125, the
plume appears to be limited to the northern third of the marsh
area. Contaminants within the marsh are estimated to be migrating
at a rate of 110 to 330 feet/year, have crossed the marsh' area
and impacted groundwater at the western edge of Country Pond.
Total VOC concentrations in the western half of the marsh are on.
the same order but somewhat lower than those observed on-site.
Figure 3 shows the distribution of VOCs off-site in the marsh.
Data concerning the spatial distribution and migration of arsenic
and nickel in groundwater, though limited in quantity, suggest
that these contaminants are migrating off-site in groundwater.'
o Air
In February 1981, EPA collected eight 2- to 24-hour air samples"in
the vicinity of the O&G/GLCC site using either a tenax or a charcoal
trap. Samples were analyzed for VOCs by GC/MS. The data provided
in Appendix H of the RI/FS indicate no detectable levels of
'VOCs, with a detection limit of 50 ppb. GZA monitored air quality
on- and off-site duri~g site drilling operations using an organic
vapor analyzer (OVA). VOC background. concentrations both on-site
and off-site were observed to be on the order of 0.2 to 0.4 ppm
(200 to 400 ppb) during the September to December 1983 field
exploration program. Since this concentration is near the detection
limit of the OVA instrument, the above estimates may be considered
to be a conservative estimate of background ambient air conditions
prevalent both on- and off-site. The lack of discernible difference
in on-site and off-site background OVA readings suggests that
emissions of organic vapors ~uring the site exploration program
occured at concentrations below approximately 200 ppb. Though
data are limited, it appears that the threat to human or environ-
mental receptors posed by emissions of contaminants to the atmos-
phere is minimal. However, circumstances that alter existing
site conditions, such as excavation of on-site materials or
extensive remedial activity, should be accompanied by an air
quality monitoring program to protect on-site and off-site receptors
and to provide additional data concerning this potential contaminant
migration pathway.
-------
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DIST!tIBU!'ON OF TOTAL VOL~TILE ORGAi~ICS
(DECE~BER 1984-FEB~UARY1986)
o &G/GlCC SOTE
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-------
RISK ASS~SSME~T
A baseline risk assessment was conducted to evaluate the risk to
public health and the environment associated with the O&G/GLCC site
in the absence of remedial action. The risk assessment was develop-
ed as follows: identify contaminants of concern: describe pathways
of exposure associated with site contaminants: estimate l~vels of
exposure and determine populations potentially exposed: characterize
potential risks to humans and the environment.
Contaminants of Concern
A variety of different chemicals were found at the site, including
volatile organic compounds (VOCs), acid and base/neutral (ABN)
compounds, metals, cyanide, and PCB/pesticides. Many of these con-
taminants occur at substantial concentrations on-site, but consider~
ably fewer have be~n observed to be migrat~ng off-site. The VOCs
appear to be the most mobile of site contaminants. VOCs have been
observed in down~radient groundwater, surface water and sediments.
PCB/pesticides, AB!~ com~ound~, metals, and cyanide appear to ~e less
mobile. possible exceptions include arsenic and nickel, where data
suggest downgradient migration. ABN co~pounds have been detected
at relatively high levels in the marsh area. PCB/pesticides have
not been observed in downgradient groundwater or surface water.
PC~s nave been identified in the ppm ran~e in South Brook sediments
on-site and within the marsh area, as well as in on-site soils.
The various chenicals fdund on and off-slte may cause a variety of
different adverse health effects, depending upon the type of chemical
and the concentration found. Some of the compounds present are
known or suspected human carcinogens, such as benzene, arsenic,
tetrachloroethylene, trichloroethylene and l,2,dichloroethane,
whereas other compounds may cause kidney and liver disorders and
other adverse effects if chronic exposure to sufficient levels occurs.
Exposure Pathways/Exposure populations
There are a variety of potential pathways of exposure to chemicals
at the O&G/GLCC site. The following pathways were evaluated: ingestion
of groundwater by contact \Jith contamination in overburden, bedrock
or Country Pond: ingestion of contaminated food, primarily focusing
on fish consumption: inhalation of contaminated vapors or particulates
from the site, dermal contact with contaminated soils, sediment or
water on or off-site1 ingestion of or dermal contact with contaminated
.media by birds and wildlife visiting the site.
EPA believes that based upon the risk assessmen~ and the informa-
tion available, the on-site soils present a direct contact risk.
The soils also pose a risk as a source for the contaminated ground-
water. The contaminnted ~roundwater on-site and in the marsh pose
a human health risk to anyone who drinks the water. The PCBs in
the sediment also pose a human health risk through ingestion.
-------
Risk Characterization
High levels of contamination are present on site, and have migrated
in the groundwater east of Route 125 to where the marsh and Country
Pond meet, as well as under the Pond itself. The Court has
found that many of the chemicals are present on site in concen-
trations much higher than acceptable levels. Sampling data from the
the RI/FS show that many hazardous substances in the soil and
groundwater continue to be present in concentrations substantially
above acceptable limits. Humans and biota may be exposed to
these concentrations through ingestion, inhalation and dermal
contact. Although on site risks were not quantified, they are
potentially significant, as the site is accessible to humans and
wildlife. This is particularly so since the site has the potential
to be developed. Although most of the on site soil data indicates
subsurface contamination, this does not preclude exposure, as
areas of contaminated soils may be disturbed now or in the future,
resulting in an opportunity for exposure. Moreover, surface
contamination existed in the pa~t, and such contamination may continue
to be present.
For the groundwater ingestion pathways, results of sampling per-
formed on groundwater on site and in the marsh revealed levels
of various contaminants at concentrations to present a considerable
risk if the site was ever developed and a person installed a
well and consumed the water.
-------
DEVELOPMENT OF ALTERNATIVES
The remedial~alternatives for the Q&G/GLCC site were developed and
evaluated using the "Guidance on Feasibility Studies under CERCLA"
and the IJational oil and Hazardous Substances Pollution Contingency
~lan (NCP) 40 C.F.R. S 300.68 as guidance. To the extent that
it was both possi~le and appro~riate at least one alternative was
oeveloped in each of the folloiwng categories, as required by 40
C.t-'.R. S 300.68(f)(1) of the NCP:
1.
Alternatives specifying off-site storage, destruction,
treatment, or secure dispo~al of hazardous substances at
a facility approved under the Resource Conservation and
Recovery Act (RCRA). Such a facility must also be in
compliance with all other applicable EPA standards (e.g.,
Clean Air Act, Toxic Substances Act).
2.
Alternatives that meet allapplicable..or relevant federal
public health or environmental standards, guidance, and
advisories.
3.
. ,
Alternatives that exceed all applicable or relevant federal
public health or environmental standards, guidance, and
advisories. ...
4 .'
Alternatives that meet CERCLA goals but do not attai~ all
applicable or relevant federal public health or environmental
standards, guidance, ana advisories.
5.
No action alternatives.
Prior to the development of alternatives, the Feasibility Study
pertormed an evaluation of general response actions and technology,
screening for inclusion in proposed remedies applicable to the O&GI
GLCC site. General response actions are broad response categories
based 0.1 the finding,; of ii-aId wotl. co.1duct~C:. Tech;1o:'o;y scr.aening
considers the waste-limiting (waste characteristics that limit the
effectiveness or feasibility of a technolo;y) and site-limiting
(site characteristics such as soil permeability that preclude the
use of a technology) factors unique to the O&G/GLCC site, and the
level of technical develo~ment for each technology.
The screening of the various technologies was based on the
following criteria:
. I .
The technology must.be reli~ble, based either on successful
implementation at other hazardous waste sites, or in
comparable applications:
2 .
The technolo~y must be technically feasible, reliable, and
applicable to site conditions and waste characteristic~ at
the O&G/GLCC site, based on engineering judgement: and
3.
The technology nust he capable, by itself, or in conjunction
-------
wit~ other alternatives, of addressinq at least one of the
FS object1ves.
Technolo;ies that di~ ~ot ~eet all of the above criteria were
excluded from further consideration.
Ta~le 1 lists the various technologies that were consi~ered
ap~ropriate for evaluation at this site. Technologies which
emerqed from this screening process were then combined into
source control and ~anagernent of miqration alternatives. As
a result, ~ighteen (18) remedial action alternatives, as
specified on Table 2, were developed for evaluation.
o
ISITIAL SCREENING
The eiqhteen (18) remenial alternatives have been subjected to
an initial screening consistent with 40 "C.F~R. S 300.68(q)(l),
(2), and (3) of the ~~CP to narrow the list of potential remedial
actions for further detailed analysis. The initial screenind
process eliminated the followiAg twelve (12) alternatives:
L
Alternatives lA and IS
"- 300.68 (g)(3); Do not effectively contribute to protection
of public health and welfare.
2.
~lternatives 2 - Alternative 6
- 300.68(g)(3); no not address off-site migration of
contaminate~ qroundwater. ~s a result, do not effectively
contri~ute to the protection of public health and welfare.
" 3.
Alternative 8
- 300.68(g)(3); Is not considered effective 1n adnressing
on-site source contamination.
4.
Alternative 9
- 300.68(q)(3); Is not considered effective in controlling
on-site contaminant release.
5.
Alternatives lOA & lOB
- 300.68(g)(2); Is not considered acceptable enqineering
practice since subsurface conditions are n9t conducive
to the successful use of a soil/bentonite wall.
- 300.68(g) (3); Use of cap not considered sufficient in
controlling release of contaminants and rloes not
effectively contribute to protection of public health.
6.
Alternative 11
- 300.6~(q)(3); Is not consinered effective in removinq
co~tinue~ release of on-site conta~ination ano thus
not protective of public health and welfare.
-------
TABLE 1
SIj~t!,tARY OF TECH!WLOGY SCREENING
LIS~ING OF REMEDIAL TEC~NOLOGIES
o
SURFACE WATER CONTROLS
- Gradin\J
Reveyetation
- Diversion ana Collection Systems
o
LEACHATE & GROUNDWATER CONTROLS
- Capping
- Groundwater Pum~ing
- Containment and Barriers
o
G.~S ~lIGR.~TIurJ CONTRIIL~
- Gas Collection
o
EXCAVATION & RE~1()VAL OF WA&TE & SOIL
- Excavation and Removal
- Grad i n-J
- Capping
Reve~e ta t ion
- Cover
o
RE!10VAL & C()N!AIN~1ENT Or' C()NTA~1IJ-JATED SEDI/1ENTS
- Sediment Removal
oJ
I.J-SITU 'IREAU.l:r.!
- Soil Aeration
o
DIRECT \~ASTE TREATHE!JT
- Incineration
- Biolo~ical Treatment
- Physical and Chemical Treatment
- Solid Handling. and Treatment
o
LAND DISPOSAL
- Landf ills
o
cm~T;~lI !~~ TED \'iA n:~ ~I1PPLI ES & SEHER LHH:S
-------
o
L.A.;;D US t; }
-------
TABLE 2
LISTING OF REMEDIAL ALTERNATIVES
ALTERNATIVE
NUM8ER
DESCRIPTION
IA
No action
1B
IC
No action: with site monitoring
No action: with site monitoring and land
use restrictions
2
RCRA GLCC site cap: O&G source excavation
an~ relocation
3
RCRA GLCC site cap: O&G source excavation
an~ relocation: and ~isposal or aeration
on-site of highly contaminated soils,
wastes, and sediments
4
RCRA GLCC site cap: O&G source excavation
a~1 relocation; ~~d complete perimeter
soil/bentonite cutoff wall
5
RCRA GLCC site cap: O&G source excavation
and relocation: and upgradient soil/
hentonite cutoff wall
'5
RCRA ~LCC site ~ap: O~G sourc~ 9xcavation
and relocation: and upgradient groundwater
interceptor trench: disposal or aeration
on-site of highly contaminated soil, wastes,
and sediments
7
RCRA GLCC site cap: O&G source excavation
and relocation: and upgradient groundwater
interceptor trench: disposal or aeration
on-site of highly contaminated soil, wastes,
.and sediments
8
Groundwater extraction .and treatment: RCRA
GLCC site cap: O&G source excavation and
relocation
9
Ground~ater extraction and treatment: RCRA
GLCC site cap: O&G source excavation and
relocation: disposal or aeration on-site
of hiqhly conta~inated soil, waste, and
-------
10;
Ground~3ter extraction and treat~ent;
RCRA GLCC site cap; O&G source excavatio~
and relocation: perimeter soil/bentonite
cutoff wall
lO~
Groundwater extraction and trp.atment: RCR~
GLCC site cap: O&G source excavation and
relocation: upgradient soil/bentonite
cutoff wall
11
Groundwater extraction and treatment: RCRA .
GLCC site cap: 0&0 source excavation and
relocation: upgradient groundwater
interceptor trench
12
Groundwater extraction and treatment: RCRA
GLCCsite cap: O&G source excavation and
relocation: upgradient groundwater
interceptor trench: disposal or aeration
on-site of highly contami"lated 'soil, waste,
and sediments
13
Alternate water supply: groundwater extrae=
tion and treat~ent: RCRA GLCC site cap:
O&G source excavation and relocation:
upgradient groundwater interceptor trench:
disposal or aeration on-site of highly
conta~inated sqil, waste, and sediments
14
Complete removal of on-site and off-site
hazardous soils, waste, sedi~ents, ground=
water, with off-site disposal
15
Excavation and on-site treatment of
contarninate~ s~ils, ~a~t9s, and ~edimen~~;
groundwater extraction and treatment:
-------
DETAILED EVALUATION OF ALTERNATIVES
A detailed evaluation of each of the six (6) alternatives re~aininq
after the initial screening was conducted in the RI/FS consiste~t
with 40 C.F.~. S 300.68(h) of the NC~. For each alternative,
thg followi~g factors, as appropriate, were considered:
(1) Detailed cost estimation, including operation and maintenance
costs, and distribution of costs over time:
(2) Evaluation in terms of engineering i~ple~entation, reliability,
and constructibility:
(3) A~ assessment of the extent to which the alternative is expected
to effectively prevent, ~itigate, or minimize threats to, and
provide adequate protectio~ of public healt~ and welfar~ and the
environment. This included an evaluation of the extent to
which the alternative att~ins or exceeds ap~licable or relevant
and appropriate federal public health and envirorumental requirements.
Where the a~alysis determined that federal public health and.
environ~ental require~ents are not applicable or relevant and
appropriate, the analysis, as appropriate, evaluated the
ris~s of. the various exposure levels projected or remaining after
implementation of the alternative under consideration:
(4) An analysis of whether recycle/reuse, waste.~inimization,
waste biodegration, or. destruction, or oth~r advanced, innovative,
or alternative technologies is appropriate to reliaoly minimize
present or future threats to puhlic health or welfare or the
environment:
(5) An analysis of any adverse environmental impacts,
methods for ~itiqating these impacts, and costs of mitigation.
The remaininQ alternatives after preliminary screening are:
lC, 7, 12, 13, 14, and 15. A description of these final alter-
natives is included on Table 3. Table 4 lists the capital and
present worth costs for these alternatives.
Alternative lC - No Action, with Land Use Controls and Water
Quality MonitorinQ. The no-action alternative at the O&G/GLCC
.. site consists of allowinQ the site to remain in its existing
condition. ~owever, actions would be undertaken to limit the
potential risks posed by the site to public health and the environ-
ment. These actions inclu~e instituting land use controls
(security fe~cing around the site) and a water quality and fish
(environ~e~tal) monitoring program. The environmental monitoring
progra~ would allow periodic reassessment of puhlic health and
environmental ris~s ~osed oy t~e site, and would include annual
sampling of all bedrock wells within an approximate 1.5 mile
radius of the site. It is anticipated that the environmental
monitoring proqra~ would exten~ for at least the first ten (10)
ye~rs following site closure and would be extended if warranted.
-------
Table 3
. REMEDIAL ALTERKATIV~S PASSING
PUdLIC HEALTH AND ENVIRON~ENTAL SCREENING
Alternative
lC
Description
No Action: with site monitoring and land
use restrictions.
7
upgradient groundwater interceptor trench:
disposal or aeration on-site of highly
contaminated soils, wastes and sediment~:
RCRA GLCC site cap: 0 & G source excavation
and relocation.
12
u~gradient groundwater interceptor trench:
disposal or aeration on-site of highly
contaminated soils, wastes, and sediments:
groundwater extraction and treatment: RCR~
GLCC site cap: 0 & G source excavation and
relocation. - .
13
Alternative 12, plus an alternate water
supply.
14
Complete removal of on~si~e and off-site
hazardous soils, wastes, and sediments to
an off-site RCRA facility.
15
Excavation and on-site treatment of contami-
nated soils, wastes, and sediments: ground-
water extraction and treatment: site cover.
Notes:
1 .
Alternatives lC through 15 include provisions for periodic
environ~ental quality monitoring and land use controls as
discussed in Sections 2.2.2 and 2.2.3 of the FS.
2.
Alternatives 7, 12 and 13 include on-site disposal or
aeration of highly contaminated soils as follows:
a.
VOC concentrations yreater than 1 ppm and PCB concen-
trations grea~er than 50 ppm: aeration of soil to
reduce VOC concentrations to less than 1 ppm followed
by disposal in a RCRA landfill on-sit~.
VOC concentrations greater than 1 ppm and PCB concen-
trations less than 50 ppm: aeration of soil to reduce
VOC concentrations to less than 1 ppm followed by
on-site disposal under a RCRA cap.
VOC concentrations less than 1 ppm and pca concentrations
greater than 50 ppm: soil disposed in an on-site RCRA
landfill.
b.
-------
3 .
VOC co~centr~tions l~ss than 1 ~~~ an~ PC8 conce~tra-
tions less than 50 ppm: soil left in place to be
co~ered by a RCRA ca~.
Marsh sediments in drainage swale to the east of
125 to be removed to residual PCB concentrations
ppm or less. PCA material disposal on-site in a
landfill.
c .
e .
Route
of 1
RCR~
Alternative 15 includes on-site treatment to an acceptable
-------
TABLE 4
-REr1EDIAL ALTERNATIVES PASSING
PUBLIC Ht:ALTH AND E~~VIRONr1ENTAL SCREErJING
ALTERNATIVE
CA'PITAL
COST
(x 51000)
PRt:SENT
WORTH
(x S100n)
lC
No Action.
202
1,029
4,150
5,543
7
Upgradient 9roundwater interceptor
trench: dis~osal or on-site aeration
of highly contaminated soil, wastes
and sediments: RCRA cap over GLCC
site: O&G source excavation and
relocation.
6,713
10,4QQ
12
upgradient groundwater interceptor
~rench: disposal or on-site aeration
of hi~hly contaminated soil, wastes
and sediments: groundwater extraction
and treatrnen~: RCRA cap. over GLCC
site O&G source excavation and
relocations
10,787
14,358
13
Similar to Alternative 12 plus an
alternative water supply. .
33,878
34,705
14
Complete excavation and removal of
on-site and off-site contaminated
soils, wastes, and sediments to an
off-site RCRA facility.
12,073
14,023
16,298
25,723
14,825
17,759
20,847
31,236
15
Excavation and treatment of contam-
inated soi)~, w~~tfS, and sedj~en~s:
groundwater extraction and treatment:
site cover.
ts t. ima ted
Es t ima ted
Es t. ima ted
Estimated
Costs are estimated with an accuracy of -~O to +50 percent.
Present worth esti~ates are based on a 10% discount rate.
Capital costs include 25% indirect costs for desi~n and
enginee~ing and construction contingencies.
Alternatives 12 ano 13 assume 4 years of groundwater extrac-
tion ane treatment a~ 100 gpm.
Refer to the text and Appendix D for assumptions made in
esti~ating costs.
lx 10-4 cancer
1x 10-5 cancer
lx 10-6 cancer
1x 10-7 cancer
risk:
risk:
risk:
risk:
Notes:
1 .
2.
3 .
4 .
-------
. .
The no-action alternative is not appropriate because it would
not do anything to permanently and significantly reduce the toxicity,
mobility, or volume of hazardous substances at the site.
Precipitation at the site would continue to leach mobile
conta~inants such as VOCs from source areas. VOC levels in site
soils and groundwater would decrease over ti~e due to dilution
from precipitation and natural attenuation ~echanisms. The rate
of attenuation would be difficult to oredict. qowever, on-site
soils and groundwater are not exoected to a~oroac~ bac~qround
levels for mobile constituents (VOCs) within 3Q vears. In
addition, non-mobile constituents such as heavy metals and PCq's
would likely remain essentially at currently observed levels
indefinitely.
.
Alternative le would not be consistent wit~ the tec~nical require-
ments of the Resource Conservation and Recovery Act (RCR~). In
particular, RCRA requires that waste and waste residues to be
removed at closure or capped as a land~ill. Also, this alternative
does not meet the RCRA groundwater protection regulations in 40 .
CFR S 264, which require cleanup to background, ~CLs, or ~~Ls.
\Jithout effective source control, it is likely t~at on site and
downgradient groundwater quality would remain at levels on the
same order as currently observed for the next 20 to 30 years.
The more concentrated portion of the marsh VOC plume east of
Route 125 would continue to migrate and would be anticioated to
reach Country Pond in a~proximately 3 years. The capital cost
is estimated to be $202,000. The annual operation and maintenance
cost (O&~) is estimated to be $133,000. The present worth i~
$1,029,000, assuming a 10 percent discount rate.
Alternative 7 - GLCC Site Cap, O&G Source Excavation and Relocation:
upgradient Groundwater Interceptor Trench: and On-Site Aeration or
Disposal of Highly Contaminated Soil, ~aste and Se~i~ents.
Alternative 7 includes GLCC site ca~oinq, O&G source excavation an~
relocation, construction of an uogradient qroun~water interce~tor
trench, and on-site aeration or treat~ent o~ hiqhly contaminate~
soil, waste, and sediments as source control measures. GLC~ site
ca~9ing would be performed co~sistent with RCR~ technical stan~ar~s.
The u~gradient trench is intended to ~aintain groun~water levels
within the GLCC site at or near seasonal low levels. In a~~ition,
this alternative includes the lan~ use controls anrl environ~ental
monitoring program as described in Alternative lC.
Construction of a GLCC site cap and interce9tor trench would
significantly reduce the infiltration of ~recioitation into the
site soils, and reduce the rate of groundwater migration across
the GLCC site. Figure 4, which is a conceptual RCRA cap 9rofile,
shows that a cap would provide a minimum of 6 feet of clean
-------
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WASTE
MATERIAL
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NOT
TO
SCAL.E-
o£,\\
RCRA CAP PROFILE
(CONCEPTUAL)
o IG/GLCC SITe
KINGSTON.N.H.
T
2488
12"(MINIMUM)
24"
,
T
12" (01 INIMUM 1
FIGURE
-------
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NOTE:
II THE PROPOS[D AREAL EXTENT or THE SITE CAP IS
IS INTrNDEO 'OR ALTERNATIYE EVALUATION ONLY,
CONCEPTUAL AND
0'
~
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b..f
:100'
--~-'1
600'
PROPOSED AREAL EXTENT OF SITE CAP
o IG/GLCe
K8NGSTOND
SITE
N.H.
fIGUHE
~
-------
. ,.... . ~~ -, ~""..
. . . ~ ~
~aterial as a ba~rier between o~-site conta~inants and the oro~nd
surface. With proper ~aintenance, the useful life of a RCRA ca~
is considered to be at least 30 years. The proposed areal extent
of the site cap is shown on Figure 5. The cap area would be
the sane under Alternatives 7, 12, and 13.
On-site disposal or aeration would involve excavation and removal
of highly contaminated waste, soil and sediments fro~ identified
.source areas. Materials with total VOC concentrations greater
than 1 ppm, and less than 50 ppm of PCBs, would he aerated to
reduce total 'JOC concentrations to less than I ppm before placement
beneath the G~CC site cap. Materials with greater than 50 ppm of
PCB's, would either be placed within a newly constructed on-site
double-lined RCRA landfill or transported off-site to a licensed
PCB treatment or storage facility. The decision to dispose the
PCB material on-site or off-site would depend on the relative
costs as well as environmental, public health, and institutional
consideration. Figure 6 shows the identified areas for source
re~oval which would apply for Alternatives 7, 12, 13, and 14.
Alternative 7 is expected to have significant long-term environ-
mental benefits beyond the nQ action alternative. Exposure of
biota to on-site contaminants would be effectively eliminated
tnrough on-site source control measures, particularly site capping,
which would place a 6-foot thick barrier of soil between wastes
and the ground surface. By cappinq contaminated soil on-site,
off~site transport of contaminated sediments to North or South
Brook would be effectively eliminated. This should eli~inate
further accu~ulation of PCE-contaminatea sedi~ents in South
Brook, halt the further deposition of PCB-contaminated sedi~ents
in the marsh, and li~it the off-site transport of VOC's and heavy
metals by the surface water pathway. By limiting the transport
of contaminants to these surface water resources, it is expected
that the adverse impacts on both the surface water flora and
fauna would be reduced. .
There would be a direct impact to the South Brook wetland from
channelling South Brook. Construction of the lined open channel
would entail destruction of approximately one acre of wetland
area along with flora and biota living within the South Brook
wetland channel. Site reconnaissance of the South Brook wetland
area indicates that oak, red maple, low bush small cranberry,
princes pine, check berry, white pine, eastern hemlock, maple
leaf viburnum, and partridge berry could all potentially be
adversely affected or destroyed within the limited area. The
site reconnaissance also indicates that the South Brook wetland
does not support a large fish or wildlife population.
Adverse impact to portions of the South Brook wetland outside of
the Main channel can be limited by careful liner construction
which would be confined primarily to the channelled area~ It is
likely that, over time, some veqetation would be naturally re-
-------
~
established in the channel and alo~q edges of the channel prevlously
disturbed by liner construction operations. Therefore, considerinc
the small area a~d observed limited functional value of the South -
Brook wetland as discussed in the wetlands assessment, the overall
impact is limited.
PCB sediments in South Brook east of Route 125 would be removed
and contained on-site in a RCRA landfill. The total quantity of
PCB sediments east of Route 125 is estimated to be approximately
50 cubic yards, and is estimated to extend approximately 100 feet
out into the marsh. Therefore, the impact to the marsh wetland
is anticipated to be minimal.
Construction of the site cap would entail destruction in the
southern portion of the North Brook wetland area on-site. Because
very little veoetation beyond sparse grasses and light bush was
obse~ved within this limited area, the impact to the North Brook
wetland is considered insionificant. No .construction.would be
required elsewhere in the North Brook wetland.
North Brook and South Brook'surface water quantities would increase
as a result of runoff from the capped area. The increase in runoff
is anticipate~ to have a beneficial .impact to both wetland areas
via provision of additional water. North Brook and South Brook
surface water quality would also be improved by effectively
eliminating offsite transport of contaminated surface runnoff and
. by channelling South Brook. .
. .
Groundwater intercepted by the interceptor trench will he discharged
to South Brook, resultina in increase surface water flow to ~he
Country Pond area at this point. It is anticipated that discharge
from the interceptor pipe will be on the order of 5 gpm. Considering
the large size of the marsh, it is anticipated that only beneficial
impacts, if any, would result from this small additional discharge
Ot clean water. .
Impact of the wetland areas due to sedimentation from excavation
and construction activities is anticipated to be insignificant if
proper erosion and sedimentation controls, includinq siltation
fences or temporary siltation ponds, are carefully constructed.
LimitinQ excavation and construction activities to drier times
of the year would also serve to limit erosion and sedimentation.
By reducing further. contaminant contributions to site groundwater,
. natural attentuation processes would gradually improve on-site
and downqradient water ~uality. It is estimated that maximum
VOC conc~ntrations in the ~etlands would be reduced by approximately
an order of maqnitude within a period of 20 to 30 years after
institution of effective on-site source control measures. In the
meantime, conditions discussed in the baseline wetlands assessment
would likely prevail.
-------
, -'
~urinq this period and bey~nd, overburden groun~water resources
within and in the vicinity of the estimated limits of plume
miqration would remain unusable. Overburden groundwater con-
tamination within this area would continue to provide a potential
source of degradation of bedrock aquifers in the area.
Alternative 7 would allow the concentrated portion of the VOC
contaminant plume within the wetlands to continue its easterly
.migration toward Country Pond. The projected impact of this
portion of the pluMe on Country Pond would result in further
degradation of Country Pond sediments, water quality, and biota.
As discussed in the baseline risk assessment, this impact would
likely result in detectable levels of VOC's in Country Pond
surface water (10 to 100 ug/l) as well as increased exposure
levels to Country Pond biota and fauna.
The RCRA cap and landfill would be designed consistent with RCM
technical standards. Since hazardous wastes would reMain on-site,
both closure and post-closure requirements for a hazardous ~aste
disposal facility, 40 CFR ~ 264, Subpart G, and 40 C.F.R. S 2~4.3l0
would be relevant and appropriate. This alternative does riot
cOMply with RCRA groundwater.protection regulations, 40 CFR
S 26~, Subpart F, since this alternative does not provide for a
corrective action program to address existing groundwater
contamination at the site. RCRA siting standards for a disposal
facility (40 CFR S 264.18) include reauirements that the site be
located outside. a 100-year floodplain and rnore than 200 feet from
an active fault would be applicable to t~e on-site landfill..
These requirements are likely achievable at the site. However,
because PCB-contaminated soils (greater than 50 ppm) would be
disposed on-site, disposal would also be subject to Mroe stringent
requirements set forth in the Toxic Substance Control Act (TSCA -
40 CFR S 761).
In ~dditj~n to R~R~ rea~ire~en~s, PCA waste ]andf.il~ und~r T:C~
is required to have a 50-foot separatlon distance between the
landfill liner and the seasonal high aroundwater table (40 CFR
S 76l.75(b)(3». This requirement could not be met at the O&G/GLCC
site, where the seasonal high groundwater table is generally
within 5 feet of ground surface. Exceptions to this requirement
can be granted provided tnat no consequent adverse impacts be
demonstrated.
Because the removal 'of contaminated sediments from the wetland is
provided for, Alternative 7 would be in compliance with Executive
Order 11990 (wetlands). Further, no desiqned discharge of waste
is anticipated to occur to the wetland.
The capital cost is estimated to be $4,150,000. The annual O&M
costs are estimated to be S193,000. The present worth is $5,543,OOC
assuMing a 10 percent discount rate.
-------
Alternative 12 : GLCC Site Cap: O&G Source Excavation and Relocation;
Groundwater Extraction and Treatment; Upgradient Groundwater
Interceptor Trench; Limited On-Site Aeration or Disposal of
Highly Contaminated Soils, Waste, and Sediments. T~e GLCC site
cap, O&G source excavation and relocation, a groundwater interceotor
trench, and on-site disposal and treatment of source materials
disc~ssed previously for Alternative 7 would be orovided as
source control measures. To mitigate t~e effects of conta~inants
which have already entered the groundwater, a groundwater extraction
and treatment program would be undertaken.
Groundwater extraction and treatment is a CO~~on an1 succes~ful
re~edial technology at ~azardous waste site~. T~e areas that
groundwater would b~ extracted from are the sa~e as t~ose oreviouslv
described under Alternative 9. The Drooosed qroundwater treat~ent
train shown on Figure 7 was develooed sDeci~icallv for t~e
O&G/GLCC site. T~e useful li~e of this alternative is exoected
to be at least 30 years. Assu~ing effective source control,
groundwater recla~ation goals, once achieved, s~oul~ last in~efinite1v.
The operation and maintenance req~~rements (O&~), however, ~or
groundwater extraction and treat~ent are much greater t~an for
Alternatives lC and 7. ~dditional environmental benefits and
concerns relevant to Alternative 12, beyond those of Alternative
7, are discussed bel~w.
Soils: Environmental pathways associated with on-site soils
would be significantly reduced through construction of a RCRA
cap and O&G source excavation and relocation.
Air: Groundwater treat~ent would likely result in volatile
organic air emissions due to the air striooer. However, these
emissions could be controlled with a vapor recovery unit. Other
treatment processes are not expected to have significant air
e~issions.
Wetlands: Construction of an access roadway for drilling of
groundwater extraction wells could adversely afFect t~e ~arsh
wetland area via destruction of wetland vegetation beneat~ t~e
roadway fill. Characteristic olant sDecies observed in the mars~
wetland including highbush bluberry, white oa~, red ~aole, reed~,
cattail~, and ~eadow sweet could all be imoacted. It is unli~elv
that construction of an access roadway would a~versely imoact
flood storage of the marsh wetland due to the relatively limited
areal extent of the roadway fill and the anticioated.east-west
roadway alignment which would not serve to da~ water be~ind the
fill. Further assessment of the roadway imoact on t~e marsh
during the pilot scale design Dhase mav be warranted. IF furt~er
studies- indicate detrimental imoact, t~e roadway could be excavated
from the marsh, and marsh vegetation reestablished once groundwater
extraction and treatment has been completed.
-------
Groundwater: While the actual extent of groundwater recla~ation
would be established throug~ institutio"al require~ents discussed
below, groundwater quality beneath a"d downqradient of t~e site
would be sUbsta"tially imoroved. Conta~inated grou"dwater t~at
is likely to be disc~arged to Country ~ond and t~e ~ort~ qrook
inlet would be reduced as would further of~-site ~lu~e ~i~ratio"
during the life of t~e groundwater extractio" oroqram.
Reducing overburden groundwater conta~ination, as well as
performing limited on-site groundwater extraction from bedrock,
would reduce future exposure of bedrock groundwater to site
contaminants. In addition, overburden extraction and on-site
source control actio~s, would reduce the ~otential for downward
hydraulic gradients that would ot~erwise cause contaminant
migration into bedrock.
Surface Waste: By intercepting contaminated
its discharge into Country Pond, contaminant
Pond water and sediments would likely remain
those presently observed. ...
In addition to the institutional requirements previously discussed
for Alternative 7, additional requirements for groundwater ex-
traction and treatment would be satisfied. This alternative
would allow RCR~ groundwater protection regulations, 40 CF~
S 264, Sub9art F, to be met, w~ich would not be ac~ievable under
Alternative 7.
groundwater prior to
levels in Country
at levels similar to
The Clean Water Act would be a90licable to surface water disc~ar~e
of treated groundwater. The technical requirements for obtaining
a NDPES permit for discharge to surface water would li~elv ~revail
prior to such a disc~arge being imoleme"ted. T~e decisio" to
select surface water discharge of treated effluent instead of
groundwater discharge would be made from groundwater treatabilitv
studies.
The capital cost is estimated to be $6,713,OO~. The annual O&~
cost is estimated to be $948,00Q. The oresent worth is esti~ated
to range between $10,499,000 for a treatment duratio" o~ 4 years
to $14,959,000 for a treatment duration of 25 years.
Alter"ative 13 is identical to Alternative 12 wit~ the addition of t~e
immediate develo9rnent of the alternate water supply system for the
area I mile west of the site and 1.5 miles nort~, south, and east of
the site.
-------
A~ticipated environmental impacts of the response are similar to
those discu.sed for Alternative 12. In addition, the construction
of an alternate water supply system would effectively eliminate
risks associated with ingestion of and washing in contaminated
groundwater. Also, eliminating the withdrawal of bedrock ground-
water within the study area would prevent diversion of contaminated
groundwater to new or existing bedrock wells, reducing the risk of
migration of contaminants with bedrock groundwater.
The implementability of the proposed water supply system cannot be
fully assessed until the hydrogeologic studies are completed. There
is no assurance that a suitable overburden groundwater resource would ~
found within the i~ediate area. If this were the case, a groundwater
resource some distance away from the study area would have to be
considered. Water may have to be purchased and transported from
the nearest existing municipal water supply system in Exeter, NH
or Haverhill, MA, which are approximately...10 miles away.
An additional environmental concern would be the short-term inconven-
ience to area residents during installation of water distribution
pipes. The disruption would include noise and dust from construction
operations. .
In addition to the institutional requirements specified under Alterna-
tive 12, an alternate water supply would also be subject to drinking
water standards promulgated under the Safe Drinking \~ater Act (SDWA).
The caDi tal cost is estinated to be SlO,)87,000. The annual O&M cost
is estimated to be 5913,000. Variations in the durations of groundwate
extraction and treatment result in a present worth ranging between
S14,358,000 (4 year duration) and S19,130,000 (25 year duration).
Alternative 14 - Comolete Removal of On-Site and Off-Site Hazardous
Soils, Wastes and Sediments to an Off-Site RCRA Facility. This
alternative w~uld jnv~~ve th~ ~omplete r~m~val ~~ All :ontaminA~ed
on-site and off-site soils (marsh sediments). Based on available test
pit data, approximately 54,000 cubic yards of conta~inated soils,
waste, and sediments would be excavated and transported off-site in
accordance with RCRA standards to a licensed RC~~ treatment, storage,
or disposal facility. This alternative would also include the
demolition of existing site structures and removal of underlying
contaminated soils. The extent of the area to be excavated is shown
in Figure 6.
.The removed material would be replaced by an equal volume of clean
soil. Following soil replacement, the site would be graded, loarned,
and seeded.
With the complete removal option, less stringent land use controls
may be appropriate. For instance, limited on-site development may
be considered but there may be no need for a security fence.
-------
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IDENTIFIED AREAS FOR SOURCE REMOVAL
rr&!7\
o & 01 GLCe SITE
KINGSTON, N.H.
-------
.GROUNDWATER TREATMENT TRAIN
(CONCEPTUAL)
o &G/GLCC SITE
KINGSTON, N.H.
Con:&~inatec groundwater
Flow Equalization
"
Flocculating
agents
,
Precipitation to remove
. Fe,Hn,Ni,As, ot.her
metals
Flocculation, sedicenution, ~
filtration
.
Preci?i:a tin,
Cher.:ica.ls
Air st.ripping
!
. .
Biological 'treatment -
Ion. exchange to rem~Ve
As and other metals
DlScharse of treated 'groundvater
@b\
Sludge de~a:ering
solids to disposol
~£ffluent vapor to
- ,further tr~.atr:e:'l:
1£ wa::ran:eo
Sludge t.o disposal
-------
E~viro~~c~tal effects of Alternative 14 are similar to those ciscusse=
for Alte~native 7. Additional impacts are discussed below.
The cOMplete removal of surficial soils from the site would be a
substantial operation that would require extensive on-site activity.
This on-site activity would require careful management to control the
discharge of VOC's and fugitive dust to the air. - Protection of the
environment would be addressed through an air monitoring program as
well as through control of excavations.
A potential concern would be possible off-site environmental impacts
due to the transport of waste materials to a suitable RCRA/TSCA
facility. Considerable off-site transportation of waste materials
would occur, with the potential risk of accidents that may result in
discharge of contaminatec materials to the environment. It is estirnat
that 2,500 truckloads of contaminated material would leave the site
onto Route 125.
Alternative 14 is a complete removal option. From a public health anc
e~viro~mental perspective, this alternative is similar to Alternative
7, in that the on-site contaminant source .would be effectively elimi-
nated. Off-site contaminant~! with.the exception of contaminated
sediments, would largely be left as is.
This alternative would create greater risk of short-term expo-
sures than Alternative 7. The large amount of excavation and
transport of contaminated materials could result in particulate
and vapor dispersion. This risk could be addressed through
design of excavation procedures and an aIr monitoring program.
The off-site transportation and disposal operations under this
alternative would be subject to RCRA regulations 40 CFR S 262 and 263,
and in the case of PCB contaminated soils, 40 CFR S 761 of the TSCA
regulations. Relevant RCRA and TSCA regulations include requirements
fer ccntainerization, manifesting, anrt transoortation ef ~xcavated
materials. The excavation operations would be conducted in accordance
with relevant OSHA regulations. The removal operations may' also be
subject to disposal facility closure requirements, 40 CFR S 264,
Subpart G.
Alternative 14, however, would not be consistent with RCRA groundwater
protection regulations, 40 CFR S 264, Subpart F, since the existing
on-site and off-site groundwater contamination would not be addressed.
The capital cost is estimated to be S33,878,000. The annual O&M cost
is S133,000. The present worth is 534,705,000, assuming a 10 percent
discount rate.
Alternative 15 - Excavation and On-Site Treatment of Contaminated
Soils, Wastes and Sediments: Groundwater Extractlon and Treatment.
This alternative would involve the excavation of contaminated material
from the entire O&G/GLCC site, and on-site treatment of these contami-
nated materials via incineration. All soils, wastes, and sediments
-------
W'
containi~9 PCB concentrations qreater than 50 ppm and VOC cor.ce~-
trations gr~ater than that deemed "acceptable" would be incinerated.
The selected level of acceptable residual soil contamination
would be based upon the evaluation of the corresponding estimated
cancer risk for th~ leachinG of residual conta~ination frc~
on-site soils and ~igration of contaminants in the groundwater to the
mars~/pond interface.
Estimates of the quantities of contaminated material that must be
°excavated to achieve an acceptable on-site residual soil contaminatio~
level were made by employing a two-phased contaminant transport model.
Additional soil survey studies would be required to accurately assess
the extent of contaminated soils. Nevertheless, the following
estimated residual soil contaminant concentrations and excavation
quantities are considered useful for order of magnitude estimates, and
are summarized for comparison purposes.
10-4
lO-5
10-6
10-7
Estimated total"°.
residual VOC
concentration in
on~site soils (ppb)
70,000
7,000
700
70
Esti11\ated a~ount
of soil to he '
excavated ~n-site
(cubic yards)
12,000
18,000
25,000
54,000
Esti~ated cancer
risk level at the
marsh/pond
interface
Once excavation and incineration operatipns ~re completed'othe site
would be graded arid covered. Figure 8 shows a conceptual profile
of the site cover.
In addition to the source control measures described above, Alternativi
15 includes groundwater extraction and treatment. The locations of
groundwater extraction wells and the treatment processes would be the
s~~e a~ dp.scri~ed f~r ~lternativ~ 12. H~wever, th~ qrQu~dwater treat-
ment goals would include a consideration of the on-site soil contami-
nation treatment goalsr i.e. groundwater treatment goals corresponding
to a range of cancer risk levels attributed to the groundwater at the
marsh/pond interface.
The following minimum number of contaminated aquifer volumes and
extraction/treatment times were estimated to be required based on
simple dilution theory and are considered useful for order of magnitudt
comparison purposes~
Estimated
Cancer Risk Level
at Marsh/Pond
Interface
Estimated Number of
Contaminated Aquifer.
Volumes to be Pumped'
and Treated
Estimated
Minimum Treatment
Time (years)
10-4
10-5
10-6
10-7
2 - 3
3 - 5
5 - 7
7 - 10
2 - 3
3 - 5
5 - 7
7 - 10
-------
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(VEGETATEO)
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NOT
TO
seAL E -
SITE COVER PROFILE
(CONCEPTUAL)
~1L\
o
&G /GLCC SITE
KINGSTON, N.H.
II
6
24 "
FIGURE
-------
No additional environmental impacts are anticioated beynn t~ose
alrea~y discussed for each respective response action in orevious
sections.
Alternative 15 involves t~e reduction of on-site soil and groundwater
contamination to residual contaminant concentration levels within a
defined risk level.
Also, the extraction and treatment of groundwater would reduce
increased risk due to contaminant migration through the aqui~er to
a level consistent with the degree to on-site. source control.
Depending on the level of residual soil conta~ination that will remai~
. on-site, RCRA closure and post-closure require~ents may' be aooro~riate.
This alternative would also be subject to the requirements for ground-
water extraction and treatment nreviously discusse~ under Alternative
12. Also, this on-site incineration alternative would have to satis~v
40 CFR S 264. In particular, Subnart 0 of t~is requlation in reqar~
to incinerators would ap~ly.
The caoital cost of this alternative ranqes ~rom ~1'-,~73,0~~ !or an
esti~ated 10-4 cancer risk to S25,723,OOO ~or an estimate~ to-7 cancer
risk, while the annual 0&'1 is esti~ated to be Sq93,~~~. The oresent
wort!1 of this alternative ranges from ~14,a25,~~~ to $31,'-3~,~~0.
-------
RECOMME~DED ALTER~ATIVE
Section 300.68 (i) of the !,atio~al Contingency Plan (~CP) states that
the approprlate extent of reMedy shall be determined by the lead
agency's selection of a cost-effective remedial alternative that
effectively mitigates and minimizes threats to and provides adequate
pro~ection of public health and welfare and the environment.
In order to meet the objectives of site remediation, both a source
control remedy and a groundwater remedy are necessary since neither
can provide adequate protection of public health, welfare and the
environment without the other.
EPA has determined that the following combination of source control
and groundwater remedies meets the governing legal requirements:
Source Control Remedv
The removal of contaminated soil (source control) is necessary to
minimize the migration of contaminants into groundwater and any
risk associated with direct contact with these soils.
" "
The selected source control remedy involves excavation of approximatel:
19,000 cubic yards of contamf~ated ~oil and treating these soils
on-site. Soils with PCBs levels above 20 ppm will be incinerated.
(Based on available data this is thought to be approximately
5000 cubic yards). Soil with less the 20 ppm PCB but with concen-
trations of total volatile organics compounds (VOCs) above 1 ppm
will be treated by an aeration process which will reduce the
VOC's to acceptable levels. This process will also provide for
positive controls on any releases of these contaminants to
the atmosp~ere such that any emmissions are protective of
public health and the environment. The "low temperature thermal
stripping" system similar to that being piloted at the McKin
CERCLA site in Gray, Maine, is recommended for use at this site
(Based on available data this is estimated that approximately
l4,00u cuoic yards will be traated in this manner).
Incineration is a proven treatment process for PCBs and other
organic compounds. Incineration is a high temperature process
that results in most cases in the destruction to insignificant
levels of the compounds. The costs and level of treatment provided
by incineration are not warranted for all contaminated soil at the
O&G/GLCC. The treatment time and the cost make it cost effective
and protective of pUblic health and the environment to treat the
low-level and non-PCBs soils by aeration.
The aeration (low temperature thermal stripping) process recommended
is considered an innovative or advanced technology because of its
lack of timed field demonstration. " The evaluation of this system
in terms of engineering reliability implementation and constructabilit"
(40 C.F.R. 5300.68 (h)(2)(iii» has revealed this alternative to be
technically sound: it is expected to be appropriate to reliably minimi
present or future threats to pUblic health or welfare or the environme
-------
,"
.r -. -. .
"
(40 C.F.R. S300.68(h)(2)(v)). The results of several oilot studies
at heavily conta~inated defense facilities ~ave de~onstrate~ a greater
than 99.99% removal of volatile organic comoounds fro~ CO"ta~inated
soils. Aeration is increasingly being used for t~e clean-u~ of
volatile organic contaminated soils at several industrial an~
defense sites. The ~cKin CE~CLA site in r,rav, ~aine is success~ullv
utilizing t~is process in pilot scale and a si~ilar ~rocess ~as
been selected for soil treat~ent at t~e ~etaltec~ Aerosv9te~s
NPL site in New Jersey. In addition, t~i9 9vste~ i9 also bein~
considered at the Tinkham's Garage Site in Londonderry, ~~.
The areas of excavation of the soils fro~ t~e O&G site an~ fro~
the areas of GLCC site are shown in figure 6. The cost esti~ate
for the source control remedy can be found in Table 6.
Total volatile organic conta~inants (VOCs) and PCqs wili be used
as indicators for excavation for the soil for remediation.
Clean-up levels for the soil contamination are based on aquifer
remediation goals and direct contact risk. The soil clean-up
levels for VOCs are intended to result in the minimization of tne
potential for further releases ta ground~ater. The soil clean-up
levels for PCBs are health and env'ironmentally based.
EPA's rationale for selection of 1 p~m for total volative organic
contaminants as a source control -action level- is based u~on the
information and data. presented in the RI/FS regarding soil and
groundwater contamination. ~ased upon the relative concentrations
of the contaminants of concern, identified in this section, and
the TVOC concentrations found in the groundwater and on-site
soils, EPA believes that this level is consistent with the
groundwater remediation goals. In addition the loom level is
one whic~ can be readily and efficientlY attained an~ ~onitored
using standard field instrumentation and con9truction tec~ni~ues.
The FS states that based on existing data l4,~OO cubic yards o~ V~C
contaninated soil above 1 po~ or 50 oom PCqs lie wit~in the
identified source areas. The FS conservatively estimates an
additional 5,000 cubic yards will be identified durinq the ~re-
excavation soil survey. The soil excavation volu~e is a~~roximatp.
and is based on limited field data. ~PA believes t~at t~p. volu~es
to be excavated based on the target levels, loom VOCs an~ 20
ppm PCBs will be ap9roximately 19,000 cubic yards. Re~ine~ent
of t~e estimate will be ~erformed during the pre-excavation soil
survey which will be conducted as the first phase of the source
control. Should the results 'of t~is survey indicate that t~e
contaminant distribution is such that the 1 ppm TVOC level is
not appropriate, EPA will reevaluate this Qortion o( the remedy.
Remediation of soil source areas will be. evaluated in ter~s of t~e
reduction in levels of VOCs with the underlying assumption
that treatment to the target level for this parameter will result
in nonhazardous levels of other contaminants.
-------
The site ~ill be graded, filled as necessary, covered and reveaetatec
to ins~re that the migration of any residual contanination will be
minimized and to prevent direct contact. The proposed cover design
is shown in rigure 8. The extent of the area to be covered will be
determined after the pre-excavation survey. Relevent post-closure
requireMents of RCRA will be perforned: groundwater monitorinq,
site inspection and site maintenance.
post-closure activities are felt to be necessary due to the inability
tQ totally remove all areas of contaminated soil. Implementation
of the remedy will include on-site sampling utilizing a grid system,
with frequency and grid size to be determined during design, based
on previously collected data.
The soil treatment will be performed consistent with applicable or
relevant and appropriate requirements. The incineration of the
PCB contaminated soil will be performed consistent with RCRA 40 CFR
264 subpart 0 and TSCA 40 CFR 161.70. . A test burn will be performed
prior to full scale operation.
Air emission testing will be conducted durin9 the test burn and ash
samples will be analyzed following the completion of the test .burn
to confirm that both are protective of public health and the.
environment. The test burn w~ll be designed to operate under worst
case conditions to conservatively represent full-scale incineration
emissions and ash content. The test burn will be designed to
include each of the various soil types (includinq a soil sample
fro~ the most contaminated areas on the site) and will be carried
out in full compliance with relevant state and federal requirements.
Treatment of the PCB contaminated soil wIll be consistent with the
excavation criteria of 20 ppm. The excavation criteria of 20 pprn
has been determined to be at a risk level that is appropriately
protective of public health and the environment for this site.
Based on the data obtained during the trial burn, a demonstration
will be performed consistent with the RCRA delisting evaluation
p'ocedJ~es.
Attached to this ROD are the assumptions and calculations utilized
to formulate the health based soil clean-up level for PCBs. EPA
feels that the assumptions and factors utilized to calculate the
recommended health based excavation c.riteria of 20 ppm are appropriate
for this site and are consistent with EPA draft guidance (Development
of Advisory Levels for Polychlorinated Biphenyls (PCBs) Cleanup"
prepared by the Exposure Assessment Group, Office of Health and
Environmental Assessment 5/86).
The excavation level for the PCB contaminated sediment will be 1
ppm, which EPA has determined to be necessary because it
conservatively reflects concentrations that could occur in fish
and other aquatic organisms. The use of a conservative limit is
necessary due to the potential forbioaccumulation in the food
chain.
-------
The proposed a~.ation process is an enclos_~ syste~ and air enissions
will be controlled. The aeration transfers the contaminants to an
air strea~ ~hich then passes through a fume incinerator or after
burner. It is expectec that the burner will destroy u? to 99.99%
of the conta~inants. The vented air stream will then be vented to a
stack. The air generated will meet applicable RCRA air emission
standards.
The soil aeration will be performed consistent with RCRA requirements.
As stated for PCBs the soil treatment level will be based on the
excavation criteria, of 1 ppm for total volatile organics. Based
on the results of the pilot study a demonstration will be performed
cons:stent with the RCRA delisting procedures that the treatment
residual is safe for placement at the site. The treatment syster~
will be operated at peak efficiency and VOC removal should in most
cases exceed the excavation criteria.. A pilot study will be conducted"
to demonstrate whether the aeration process and its air release
controls are effectively removing the contaminants and to ensure
that the air emissions and the residual soils are protective of
public health and the environment. The pilot study will be designed
to operate under worst case conditions to 'conservatively represent
full scale operation. The pilot study will be designed to include
each of the various soil types (includinq a soil sample from the
most contaMinated area on the site) and will be carried out .io
full compliance with relevan~ state and federal requirements.
.. .
EFA will perform an evaluation based on the results of the incinerator
and aeration pilot studies to verify the costing data used in the
feasibility study and any additional costing data used in preparation
of this ROD. EPA will make a determination based on the costing
data from the pilot studies that it is ~ost-effective to treat the
low PCB soils by aeration. . .
PCB contamination in on-site wetlands (including portions of.South
Brook at Route 125) above 1 ppm will be excavated. This will
result in short term adverse impacts on the wetlands. However,
this impact is not considered significant and wetlands are expected
t~ recover quickly. This ~ill re~'llt in cnmpliance with Executive
Order 11990 and the Fish & Wildlife Coordination Act.
In addition to the legal requirements discussed elsewhere, the Clean
Air Act and Executive Order 11990 (Protection of Wetlands) are
applicable or relevant and appropriate.
The estimated capital and operatio~ and maintenance costs for this
remedy can be found in Table 6.
.The implementation of this remedy will be as follows:
Decontamination and removal of existing site structures.
Design and implementation of soil sampling plan to determine
areas and depths of excavation.
Excavation of approximately 19,000 cubic yards of soils above
the target levels of 20 ppm of PCBs or 1 pprn of VOCs.
Excavation of sediMent in South Brook and marsh areas to
1 ppn of PCBs.
-------
o 0
~~bient air quality monitoring during remedial activities to ensure
that offsite pollutant concentrations do not reach unacceptable
levels. A detailed monitoring progra~ including onsite action
levels, site perimeter monitoring, and collection of meteorological
data will be performed.
Acceptable site perimeter levels and onsite action levels will be
developed based on applicable standards and guidance from EPA
and the Centers for Disease Control. Action levels are the
ambient levels which will trigger specific responses such as
applying additional control measures to the remedial processes
or that may temporarily cause activities to cease at the site.
Treatment by incineration of all soils with PCBs above the target
level of 20 ppm. Prior to full scale incineration a trial
burn will be performed to demonstrate that ash levels and air
emissions will be protecti e of public health and the environment.
Treatment by aeration (low temperature thermal stripping)
of approximately 14,000 cubic yards. Prior to full-scale
of the aeration system a pilot study will be performed to
that treatment levels and air emissions are protective of
health and the environment.
process
operation
demons.tra t
public
Evaluation of the incinera~ion test burn and aeration pilot
study will include a cost-effectiveness analysis to ensure
. that the costs utilized as a basis for this ROD were appropriate.
In the event the cost data needs to be revised a determination
will be made whether aeration is cost-effective given the need
.. to incinerate the PCB contaminated soil..
Treated soil will be replaced and regraded. The site will be covere
to provide adequate drainage,minimization of infiltration-and
protection from direct contact.
On-site and off-site water quality monitoring will be performed to
verifl that the ~ajor. s~u~ce areas have been sucessfully excavated.
Post-closure care including site inspection and maintainence
will be performed.
Hanaoement of Hieration Remedy
The chosen remedy involves the removal/extraction of contaminated
groundwater and the onsite treatment with discharge back to the
groundwater. A desc~iption of this remedy is as follows:
extraction of contaminated groundwater from the following areas:
(a) contaminant source areas on the O&G/GLC~ site, including
the O&G site, the caustic lagoon, Kingston Swamp, and the
area east of the GLCC building:
Route 125: .
The marsh area downgradient of the GLCC Site:
From the deep bedrock well R-4 near the border of the
site with Route 125.
(b)
( c )
(d)
-------
Extracted groundwater will then be treated onsite to meet the
State of New Hampshire requirements, Part 410, Protection of
Groundwater, ~.H. Code of Administrative rules. The treat~ent
cornponents.will be determined during design after the performance
of treatability studies. The treated groundwater will then
be discharged back to the groundwater on-site to the extent
technically feasible. Additional discharge will be to surface
water and will meet the relevant water quality criteria
and National Pollutant Discharge Elimination System (NPDES)
requirements.
Groundwater extraction and treatment will proceed for five years,
from the date of implementation. Upon achievement of the target
levels or five years, whichever is sooner, an evaluation will
be perfor~ed to insure that the target compounds were appropriate
and if the target levels have not been achieved if they are
technically feasible. Achievement of the target levels will be
defined as continuously meeting target levels for identified
contaminants of concern for a period of 3 years at the Route
125 monitoring boundary and at t~e onsite monitoring wells that
are selected during design to determine onsite water quality.
Monitoring of wetlands onsite will be canducted to insure no
detrimental impacts from the extraction of groundwater for
treatment. If negative impacts are observed, the rate of
groundwater removal will be decreased to the point that these
wetlands are not adversely impacted.
Onsite and offsite monitoring will be implemented consistent with
RCRA S264.100(d), which reauire~ the establishment of a rnonitorin~
program to assess the impact of the remedial alternative.
Off-site residential wells will be ~onitored during the
implementation of the remedial action. The frequency and
parameters to be monitored will be determined during design.
Present worth, cap\~a] ~n~ ~peratio~ and maintenance ~osting data
can be found in Table 5. The costs developed for the groundwater
treatment system were based on the various treatment units as shown
on Figure 7. The final treatment scheme will be developed upon the
completion of pilot and treatability studies.
It is EPA's policy to develop and evaluate groundwater remediation
alternatives which will achieve cleanups within a lifetime cancer
risk range of 10-4 to 10-7 (1 in 10,000 to 1 in 10,000,000). In
the selection of an alternative and associated risk range, EPA
.typica1ly takes into ac~ount the following factors:
1.
site and groundwater characteristics -"
2.
cost, reliability, speed, and technical feasibility
of each alternative
3.
current use and anticipated future need for the
groundwater
-------
4.
effectiveness and reliability of institutional ~ontrols
that might be used as part of a remedy
5.
public.acceptability of the options; and
ability to provide an alternative ~ater supply
6.
Based upon an evaluation of these factors, EPA has selected a risk
range of 10-5 as appropriate for groundwater remediation at the
Ottati and Goss/GLCC site.
In addition to the indicator compounds, the proposed treatment
scheme pro'Tides for the treatment of arsenic and other metals
as a result of sampling which showed elevated levels on-site.
The need for the ion-exchange unit or a comparable unit to treat
arsenic and other metals will be evaluated upon the completion
of pilot studies.
The selection of indicator compounds to be utilized for aquifer
clean-up is based on the relative composition of the contaminated
groundwater, the toxicity of the compounds and their treatability.
The calculation assumes additivity of risk and does not take into
account interactions of compounds in a mixture. The following"
compounds will be utilized as indicator'compounds at the site:
1,2 dichloroethane, trichloroethylene, tetrachloroethylene, and
benzene.
The following table'provides concentrations associated with a
10-5 risk level for each of the four contaminants of concern
and individual and overall risk level associated with a 5 ppb con-
centration for each of the contaminants. This calculation is based
on risk levels associated with the compounds from EPA's Office of
Drinking Water and the Cancer Assessment Group (CAG) F.R. Vol.
50, No. 219, p. 46880-46933, November 13, 1985). The risk levels
utilized are based on drinking water consumption only. The assump-
tions and calculations are consistent with the methodology in the
Water Ouality Criteria. '
Concentration Cancer Risk
Associated with Level Associated
10-5 Risk Level with 5 ppb
'.
1,2 dichloroethane
3.8
1. 3 x 10-5
-trichloroethylene
tetrachloroethylene
26
6.7
1. 9 x 10-6
7.5 x 10-6
benzene
13
3.'8 x 10-6
2.6 x 10-5
-------
EPA has determined it is necessary to remediate groundwater to
the target levels both on-site and off-site. The Route 125
boundary and on-site wells to be selected during design will be
used as the monitoring points to determine compliance with the
target levels.
EPA has determined that treated groundwater discharge'upqradip.nt
of the site is necessary, as recommended in the feasibility study.
The discharge upgradient will aid in the efficiency of aquifer
reclanation. In addition, upgradient groundwater discharge will
reduce the risk of any potential impact of surface water bodies.
Discharge to surface water would approach the natural brook flow
rates (North and South Brook) and could result in an impact to
either of the Brooks and/or the downgradient marsh.
In addition to the legal requirements discussed elsewhere, the
applicable or relevant and appropriate Federal and State air reQuire=
ments will be complied with for any air releases from the groundwater
treatment system.
-------
VI.
Rationale For EPA's Selection of Its Preferred Altern~tive
A.
Legal Requirements
1.
The Legal Requirements That Govern T~is ROD
By virtue of se~tion four of th~ Superfund Amen~ments ann
Reaut~orization Act of 1986 (S~RA) (enacted October 17, lqq~),
EPA's reme~ial alternative must meet t~e requirements o~ the
compre~ensive Environmental Res~onse, Compensation, ann Li~hilitv
Act of 1980 (CERCL~), 42 U.S.C. ~ Q601 et seq., as a~en~e~ by
SAR~, and the requirements of its governIng requlati~~s, t~e
National Oil and Hazardous Substances Pollution ContinqAnCy clan
(NCP), 4~ C.F.R. Part 300. 1/ Accordingly, t~e ~gency ~as selecten
a remedy that is consistent-with its governin~ statut~, includinq
the cleanup standards in section 121 of S~RA, anti its requlations.
2.
The Substantive Legal Requirements Themselveg
Under its legal aut~orities, EPA's responsibility at
Superfund sites is to underta~e reme1ial actions that are
necess.1ry in order to protect .the public ~ealt~ or welfare or
the environment. 42 U.S.C. ~ 9604(a)(1): SAR~ ~ 121. In se~tion
121 of SA~~, Congress provides two guidelines for t~e Agency to
follow in sele~ting reme~ies t~at are atiequately protective.
First, in Section 12l(b), Congr~ss creates an extremely stronq
statutory preference for remedial actions in w~ic~ treatment
permanently and significantly reduces t~e volume, toxicity or
mobility o~ the hazardous substances, pollutants or c~nta~inants.
In asse3sing various permanent solutions, EPA must g~ecificallY
ad1ress t~e lonq-term effectiveness o~ the different alternatives.
EPA shall at a minimum take into account:
(~)
(B)
(C)
(D)
(E)
(F)
(G)
the lonq-ter~ unc~r~ainties associatei wit~ lan~
disposal:
the goals and requirements of RCRA:
the persistence, tQxicity, mo~ility an~ pronengities to
bioaccUm\llate of the hazar~ous suhstances an~ constitue~ts:
t~e sho~t and long term potential f~r ativerse ~Aalth e~fects
from human exposure:
long-term maintenance costs:
the potential for future remedial action costs if the
alternative remedial action in question were to fail: and
the potential threat to human healt~ an1 the environment
associated with excavation, transportion, and redisposal,
or containment.
Congress prescribes that, in choosing its final remedy, EPA
select a remedial action that uses permanent solutions ani
alternative treatment technologies or resource recovery
technologies to the maximum extent practicable.
must
-------
Further, in. section 121(d), Congress provides that EPA's remedial
action, when complete, must comply with applicable or relevant
and appropriate environmental standards estab11shed under Federal
and State environmental laws (such applicable or relevant and
appropriate requirements sometimes will be referred to asARARs).
Examples of such laws considered 1n this document are RCRA,
TSCA, and State standards.
B.
Legal Requirements Applied To This Site
The discussion in the sections above and the data in the RI/FS
establish that substantial amounts of hazardous substances
currently are present on site, in the groundwater and in the
soil; that many of these hazardous substances are present in
high concentrations; and that several are potential carcinogens.
These high concentrations potentially pose several types of
risks. The groundwater is unusable as a drinking water source
because of the contamination. In addition, the contaminated
soil may pose a risk through direct contact. Third, the
VOC-contaminated soil also poses an indirect risk; if left -
unremediated, the VOCs will continue to migrate into the
groundwater and prolong and exacerbate the groundwater
contamination. In short, the site in its current condition
presents a threat to human health and the environment in several
way s .
1.
A Treatment-Based Remedy Is Appropriate For This Sfte
EPA has three basic options for addressing the risk to human
health and the environment that the site presents. First, there
is a no option alternative. Under this option, the Agency would
fence the site and otherwise prevent access to it. In addition,
the Agency would monitor residential drinking water wells in
close proximity to the site to ensure that they are not
being adversely affected. EPA's remedy would do nothing to
eliminate or minimize the various types of threats themselves.
EPA rejects this no action approach for four related reasons.
First, this approach would not adequately protect human health or
the environme~t. Institutional controls are unreliable to prevent
exposure to a site, especially over a substantial period of
time. This inadequacy is of particular concern in this case
since presently the,site is relatively remote and trespassers
might well go unnoticed. In the future, a problem could occur
for the opposite reason. The general vicinity of the site could
undergo rapid development if it follows the trend in other parts
of southern New Hampshire. The greater amount -bf human activities
in the area of the site would pose problems in preventing access
and exposure to the site.
-------
Second, this approach does not comply with ARARs. A no action
alternative would not comply with either RCRA, TSCA, or State
standards. ~I
Third, Section l2l(b) of SARA requires that the Agency select
remedies that permanently and significantly reduce the volume,
toxicity, or mobility of hazardous substances to the maximum
extent practicable. As is discussed elsewhere, other alternatives
. which better satisfy this statutory preference are available for
this site. The no action alternative is at the opposite
end of the spectrum in terms of permanence from this statutory
preference.
Finally, in addition to protecting human health, a second EPA
statutory ~andate is to protect the environment. See~, SARA
~ 121. A no action remedy which includes institutional controls
to prevent access to the contaminants is clearly not the cost
effective way of protecting the environment. Section 101(8) of
CERCLA defines "environment" to include groundwater witl'\in the
United States. As was noted above, the contaminated groundwater
under the site once was usable and it is part of an aquife~ that
currently is being used. Pr9tectin6 the environment under CERCLA
includes both preventing additional environmental harm and restoring
t.he "harmed" environment to a usable state. Ins ti tutional controls
would be completely ineffective 1n accomplishing this goal.
In short, the Agency's rationale for rejecting a no action alternative
is as follows. First, such a remedy would be unreliable and of
questionable effectiveness in terms of protecting human health.
Second, such a remedy would be totally ineffective in terms of
protecting the environment. Third, such a remedy does not comply
with relevant and appropriate requirements. Finally, no action
is exactly what Congress did not intend to encourage in creating
a strong statutory preference for remedies that destroy wastes.
EPA's other two options for eliminating or minimizing the risk
that the site presents are (1) to contain the hazardous substances,
or (2) to destroy or significantly reduce the toxicity, mobility, or
volume of these hazardous substances. 3/ EPA has selected
the option of permanently and significantly reducing the toxicity of
the wastes as the appropriate remedy for the site because such a
remedy would be a more reliable approach for protecting human
health and the environment, especially in light of the conditions
at this site. Such a remedy also is appropriate because it 1s
consistent with SARA's.statutory mandate that the Agency select
permanent remedies to the maximum extent practicable.
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This site is a relatively small site located in an area where future
use of the~ite for development is a realistic possibility. The
soil at the site contains several hazardous substances. Several
of these hazardous substances, including a number of the VOCs
and PCBs, are extremely toxic. Some of the VOCs are carcinogens
or suspected carcinogens. Moreover, the VOCs are unusually
mobile and the PCBs are unusually persistent hazardous substances.
Further, the continued presence of these substances on site will
"exacerbate the already high levels of contaminants in the
groundwater; this contamination prevents the present use and
will prevent the future use of the groundwater as a drinking
water source.
A remedy based on treatment of these hazardous substances in the
soil will minimize soil contamination and ensure no human contact
with soil that is contaminated at unsafe levels, by significantly
reducing the toxicity of the contaminants. This soil treatment
will have the additional benefit of assisting the cleanup of
the groundwater by eliminating the continuing source of
contamination from leaching of hazardous substances from the
soil into the groundwater.
u
EPAalso believes that the remedy of pumping and treating the
groundwater will si£nificant1y reduce groundwater contamination
and permit the eventual use of the groundwater beneath the site
for drinkin6 water. Futher, cleaning up the groundwater will
eliminate a possible source of contamination to off site surface
waters and 6roundwater." .
Finally, this remedy satisfies the statutory mandate that EPA
select a remedial action that is protective of human health and
the environment and that is a permanent solution to the maximum
extent practicable.
In contrast, the alternative of capping the VOCs and landfilling
the PCBs is not an appropriate remedy. Over the long-term there
are no guarantees that such containment will remain effective.
Further, containment will not remove the soil contamination;
leaching of these contaminants into the groundwater, particularly
the VOCs, would continue, although at a reduced rate compared to
present. unremediated conditions. Failing to treat the
groundwater would render the groundwater on site unusable
for drinking water for a substantial period of time. In addition,
the groundwater wou~d be a continuing source of contamination to
off site surface water~ and groundwater.
In short, based upon several factors, includin& (1) the greater
reliability and, hence, the greater protectiveness, of the
treatment-based approach, (2) the need for reliability in light
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» .
of the substances present at the ~ite. and (3) the strong
statutor~ preference for permanent remedies. EPA's
treatment-based remedy is the appropriate remedy for. this
site.
2.
Level and Type of Treatment
(a)
Groundwater Contamination
Portions of 40 C.F.R. Subpart F are relevant and appropriate
because they address situations similar to the site. notably.
situations where hazardous wastes are present in both the soils
and the groundwater. Subpart F of RCRA provides that groundwater
must be cleaned up to background. to MCLs. or to risk-based
alternate concentration limits (ACLs). The Agency thinks it
appropriate to restore the groundwater on site. as well as the
groundwater off site. to drinking water quality. As noted above.
this is an aquifer that is used as a drinking water source now.
and whose use can be expand~d by cleaning up this site. 4/-
Thus. risk-based levels need..to be established throughout-the
site as well as off site to ensure that all potentially usable
groundwater is of drinking water qu~lity. At this site. EPA
selected a cancer risk level of 10-' for the groundwater (EPA's
remedy also will clean up noncarcinogens 1n the groundwater.
such as metals. to drinking water standards).
EPA determined th~t its remedy should clean up the groundwater under
the site to a 10-' cancer risk range based upon several factors.
F1rst. EPA cons1dered the Agency's Groundwater Protection Strategy
(GWPS) (Office of Ground-Water Protection. August 19~4). The
GWPS provides guidance concerning how different groundwaters
thrOughout the country sho~ld be classified and to what extent
cleaning up a particular groundwater is appropriate. given where
it fits in the classification scheme. Second. EPA considered
the Agency's Draft Guidance on Remedial Action for Contaminated
Groundwater at Superfund Sites (October 1986). and the Agency's
approach to the Millcreek Superfund site. in determining that
it should consider the 10-4 - 10-7 range of risk levels in
selecting a risk level for the groundwater at the 0 & G site.
Finally. the Agency determined that it should clean up the
groundwater to a 10-5 risk level based upon the particular
conditions at this Bite.
EPA's GWPS guides the Agency in setting policies on groundwater
protectIOn. depending on the designated or potential use of the
groundwater. The Preamble to the NCP lists the ~ as one of
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the criteria, advisories, and procedures that should be considered
in developing a remedy. 50 Fed. Reg. 47949 (Nov. 20, 1985).
The GWPS provides that EPA's policy on groundwater protection
shou~ons1der the highest beneficial use to which particular
groundwater can presently or potentially be put. GWPS at 5.
The GWPS defines protection policies (i.e., policies-concerning
. levers-Qf protection and cleanup) for three classes of groundwater,
based on their respective value and their vulnerability to
contamination. Id. Class I groundwater is special groundwater
that is irreplaceable (i.e., no reasonable alternative source of
drinking water is available to substantial populations) or
ecologically vital (~, the aquifer provides the base flow for
a particularly sensitive ecological system that, if polluted,
would destroy a unique habitat). Id. at 5-6.
Class II groundwaters include groundwaters that are current or
potential sources of drinking water and waters having other beneficial
uses. Class III groundwater is not considered to be a potential
source of d~inking water and to be of limited beneficial use (i.e.,
groundwater 'that is heavily '~.aline or is otherwise contaminate~
beyond levels that could be cleaned up). To fit into Class III,
groundwater also cannot migrate to Class I or II groundwater or
have a discharge to surface water that could cause degradation. ~.
Here, the groundwater that underlies the site is Clas~.II ground-
water. This groundwater is considered to be a current drinking
water source since groundwater is used for drinking water within
a two mile radius of the site. Except for the contamination
caused by the site, the groundwater in the area is of drinking
water quality. The natural condition of the groundwater makes it
possible to develop the area, including installation of drinking
water wells in the future. There were operational drinking water
wells on site 1n the 1950's and 1960's. This groundwater also
migrates to Class II groundwater that is being used as a drinking
water source now. ,
EPA's ~erfund Public Health Evaluation Manual (OERR 1986)
establishes that in selecting a risk level for groundwater that
1s or may be used as a dr1nk1n! water source, EPA should use a
carcinogenic risk range of 10- to 10-1 (1 in 10,000 to 1 in
10,000,000). Id. at 101. See also the Millcreek ROd (issued
on May 1, 1986~y EPA Region-!), and the Millcreek Memorandum
from Winston Porter, E~A Assistant Administrator for OS~~R,
dated May 24, 1986. The Millcreek Memorandum indicates that the
goal of achieving a lO~o cancer risk level within a short period
of time (one to five years) should be used as a point of departure
in analyzing a range of alternatives. Memo at 2. In selecting
an appropriate risk level at this site,-and a time frame for
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reaching it, EPA took the following m~jor factors into account:
1.
Site and groundwater characteristics:
2.
Cost, reliability, speed, and technical feasibility of.
each alternative:
3.
Anticipated future need for the groundwater:
Effectiveness and re1iabi1itv of institutional controls
that might be used as oart of a re~edy:
4.
5.
Public acceotabi1ity of. the o~tions: and
6.
Ability to orovide an alternative water su~olv.
Concerning the a~?ropriate cancer risk level, ~~~ has selected l~-~
for the groundwater throuqhout the site and in the qroundwater that
has migrated off site. The 11)-5 levels for -1,2 ,.Hch 10roet~ane,"
trichloroethylene, tetrach10roethvlen~, and benzene innividuallv
are 3.9 ppb, 26 p~b, 6.7 o~h, and 13 o~b, respectivelv. T~ese
levels a9proach the limits of ~onitoring caoabilitv. The
concentrations discovered in the s011 after the I~~ cleanu~ and
in the ~roundwater to date ~or t~esesubstances are well above
t~ese acceotable concentrations. For examole, for
"1,2 dichloroethane, measured levels include 790 oob (groundwater),
for trichloroethylene, 3,900 P9b (soils), 3710 oob (groundwater),
for tetrachloroethylene, 160,000 ppb (soils), 9400 o~b (groundwater),
and for benzene, 1,400 ppb (soils), 500 pob (groundwater)(higher
levels in the soil than those listed above were discovered before
the I~C cleanup: such higher levels may have been missed during
the cleanup and may continue to be oresent on site even though
they were not discovered during the oost-I~C cleanuo sam9ling).
For several reasons, EPA rejects a level of 10-4. The f.ollowin1
concerns, many of which are interrelated, are a~onq the Mo~t sioni-
ficant. First, ~PA anticioates t~at there ~av be a f.uture need
for this aquifer, including the conta~inated oortion o~ it. T~i9
is a Class II aquifer, ~hat is, oarts of it are used as a source
of drinking water source, and the contaminated ~ortion of t~i~
aquifer has the poten~ial to be used as a drin~inq water source.
Given the hydrogeologic uncertainties at t~e site, ~~, does not
think it is orudent to select a risk level that, if. met everv-
where, will produce a barely ade~uate drinkinq w~ter suoolv.
This is particularly true since no alternate water su~~lv svste~
is in place, although one Dotentiallv could be installed, at
considerable expense. In addition, should the aqui~er he used
by orivate homeowners, it ~robably would be without the benefit
of treatment or consistent monitoring. qased u~on all of. these
factors, EPA does not believe that a 10-4 level would leave an
,
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adequate margin for error. EPA has ruled out levels of 10-6
and 10-7 at this time because, under the circumstances of this
site, the 10-5 level 1s adequately protective, and therefore
it would not be cost effective to clean up beyond that level.
Moreover, 10-5 for the substances involved is at the limits of
monitoring ability. As a result, 1t 1s technical infeasible to
. clean up beyond that level.
The final issue concerning the groundwater is to determine the
appropriate way to clean it up so that it attains a 10-5 risk
level. In addition to SARA's emphasis on restoration, EPA's
policies support active restoration in this case. As noted
above, the aquifer system is a Class II aquiferj it is currently
used as a drinking water source, and the contaminated portion of
the aquifer may be needed as a drinking water source in the
future. In addition, as noted above, an alternative water supply
is not currently available. Third, high concentrations are
present in groundwater that may be used, and the groundwater is
not likely to clean itself up through natural attenuation in the
foreseeable future. .
Given these facts, and the mobile and toxic nature of the
constituents, there would be significant long-term uncertainties
associated with either natural attenuation pr containment, and
both a short and long-term potential for adverse health effects
from human exposure if either approach is adopted and then fails,
particularly if the site is developed. There also would be a
possibility of future remedial action costs. The public also
has de~anded usable water quickly. In its comments, the local
citizens group, WASTE, made clear its grave concerns about the
need for an assured drinking water source, asking not only for a
total, rapid cleanup, but also for an alternate water supply as
an added precaution. All of these facts, in addition to the fact
that effective technologies are available to treat the contaminants
in the groundwater, support a need for rapid restoration.
(b) Soils
(1)
VOCs
A remedial action is required for two types of soil contamination
that are on site. ~oncerning the volatile organic compounds
(VOCs), actions are necessary to achieve short-term and long-term
groundwater objectives~ notably restoring the 6roundwater for
use as a potential drinking water source. The.Millcreek
Memorandum (at page 3), among other documents," reflects EPA's
approach of designing a source control remedy consistent with
the need to clean up groundwater. "EPA's goal in selecting a
remedial action for the source is to achieve a 10-5 risk level
in the groundwater on the site. EPA will clean up a sufficient
quantity of soils to sufficiently low concentrations to accomplish
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. .
this objective. The volume of soils to be remed1ated depends on
variables such as the mass and distr1bution of contaminants in
the ~oils. As part of the remedy, a pre-excavation survey will
be done that will lead to a refined assessment of the mass and
distribution of contaminants in the soils. EPA has costed out
this portion of the remedy based upon GZA's estimates as to the
. volume of contaminated soils, and upon its assumption that the
soils will need to be treated to 1 ppm total VOCs. The Agency
will refine its cost projections once it has completed design.
As is discussed above, the Agency has selected a treatment-
based remedy for this site because it prov1des a greater degree
of protectiveness, and because its selection would comply with
EPA's statutory mandate to select permanent remedies where
practicable. Thermal aeration is the cost effective remedial
technology for cleaning up the VOC soils. 5/ The Agency prefers
thermal aeration to the rototilling type or aeration. The former
would be much more efficient and reliable and hence it is more
likely to be effective. It also is safer in terms of its
potential emissions into the atmosphere. Consequently, the'
Agency has costed out its remedy on. the basis that it will use
thermal aeration. Nevertheless, during design, EPA will consider
proposals using rototilling and other aeration technologies as
well as thermal aeration proposals. The Agency will make a
final decision .as to the type of aeration to use based upon the
~rrect1veness and safety or. these technologies when used under
the spec1f1c conditions present at this site.
(ii) PCB Soils
PCB-contaminated soils also are present on site. Reducing the
concentration of PCBs to a level of 20 ppm would adequately
protect human health and the environment, based upon EPA Guidance
(Development of Advisory Levels for Polychlorinated BiphenYls
(PCBs) Cleanup, prepared by the Exposure Assessment Group, Office
of Health and Environmental Assessment, May 1986), and the
site-specific analysis contained in the October 29, 1986 memorandum
that is included in the administrative record. With respect to
the PCBs in the sediments, EPA has selected a concentration of 1
ppm. This l1mit is a conservative one that is based upon potential
risks to birds and wildlife.
As noted above, the. permanent remedy of thermal destruction
(incineration) rather than a containment alternative is preferable
for several reasons. Incineration is a proven treatment process
for PCBs an~ other organic compounds. It is a.high temperature
process that in most cases destroys the compounds. With
incineration, there will be none of the long-term uncertainties
that would exist if the PCBs (which are unusually persistent and
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toxic) were capped, covered. landfilled, or merely left alone.
Similarly, EPA will not need to worry about long-term maintenance
costs, about the potential for adverse health effects if containment
fails, or about the need for additional expenditures if land
disposal were tried and it failed. EPA projects that approximately
5,000 cubic yards will need to be incinerated. The Agency has
developed its costs on this basis. This figure will be refined
. during the design phase of the remedy. The Agency will make a
final decision as to the type of incineration to use based upon
the effectiveness and safety of these technologies when used
under the specific conditions at this site.
3.
Applicable or Relevant and Appropriate Requirements
(a) Groundwater
In determining the applicable or relevant and appropriate
requirements for remedial actions involving contaminated surface
water or groundwater, the most important factors to consider are
the uses of the water and the purposes for which the potential
requirements are intended.
The actual or potential use of water, and the. manner in which it it
used, will determine what kinds of requirements may be applicable
or relevant and appropriate. For Class III-type groundwater that
cannot be used for" drinking because of high .salinity or severe
contamination, drinking water standards are neither applicable'
nor relevant and appropriate. If the groundwater or surface water
is always treated at the well-head or at a treatment facility,
drinking water standards apply at the tap. Groundwater or surface
water that i5 directly used for drinking must, however, be cleaned
up to drinking water levels.
For contaminated groundwater, the applicable or relevant and
appropriate standard will generally be the RCRA Groundwater
Protection Standard (Part 264, Subpart F). The Groundwater
Protection Standard allows setting a level at background, at a
protective alternate concentrations limit (ACL), or, for a small
set of chemicals, at a specified concentration limit. For
Superfund purposes the ACL 1s generally most appropriate, based
on the use of the groundwater.
For water that is i~tended to be used for drinking, the point of
departure for setting an ACt should generally be the Maximum
Contaminant Levels (MCLs) set under the Safe Drinking Water Act.
Of course, where the groundwater being cleaned'up will be supplied
directly to 25 or more households, MCLs are legally applicable.
Otherwise, MCLs are generally the most appropriate standard
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for actual or potential drinking water.
The levels to whic~ groundwater will be cleaned uo at t~is site
are at the limits of monitoring ability. The statute rp.~uires t~at
t~e remedial action com?ly wit~ ~~LGs w~ere t~ev are relevant an~
appropriate. Because t~e levels selected in t~is remedy are
a1r.eady at the limits of our monitoring ability, t~e question o~
whether HCLGs are relevant and aporocriate at t~is site nee~ not
be reached. The levels do meet the cr090sed ~CLs that have been
established for the indicator chemicals.
State groundwater regulations are relevant and aDprocriate for
this site. State groundwater regulations require t~at EPA's
remedy treat the groundwater to achieve a 10-6 cancer risk level
for trichloroethylene and tetrachloroethylene at Route 125. !!!
Ws 4l0.05(e), 410.09, and 302.08. Conse~uently, t~e State
requirements constitute an independent basis for cleaning u~ t~e-
groundwater at Route 125 to a 10-6 level for t~ese substances.
As noted. above, EPA's remedy will treat' the grounr:Jwater on the
site, as well as at Route 125, so that t~e tric~loroet~v1ene and
tetrachlorethylene levels are each 5 o~b, whic~ is a 1~-6
cancer risk level.
(b) Soils
RCRA's closure requirements are relevant and a~~ronriate for t~e
contaminated soil. EPA's re~er:Jy, w~en com~lete, will com~lv wit~
these requirements. If EPA's remedy doe~ not sati~~v t~ese
requirements, t~e Agency will consider w~at ar:J~it10nal action
(if any) is needed.
TSCA is relevant and a09ropriate concerning the ~~qs qreater
than 50 ppm under the circumstances of the release or t~reatened
release at this site. Accordingly, ~PA has selected a remedial
alternative that attains t~e level of control requirer:J under
TSCA. TSCA requires that ~C~-contaminated s011s above 50 oom be
incinerated or landfilled. 40 C.~.R 5 76l.60(a)(4). TSCA's 50
ppm limit is not a risk or health-based standard. ~PA's remedy
is health based and will exceed this standard.
C0NCLUSION
The soil and g~oundwater at the Ottati and Goss Su~erfund
site contain high concentrations of a wide variety of hazardous
substances. Because these ~azarr:Jous substances are orese~t, the
site poses a threat to human health and the environment. £PA's
three primary options for addressing this risk are (1) to allow
the risk to continue to exist but to orevent access to it bv
imposing land use controls (the 8no action8 ootion), (2) to
minimize t~e risk by capcing the contaminated soil, an~ (3) to
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minimize tbe risk by treating the hazardous substances to levels
that are protective of human health and the environme~t.
EPA has selected the third option as its remedy. EPA has a high
level of confidence that by significantly reducing the toxicity
of the hazardous substances present at the site, this remedy
will be effective in minimizing the risk that the site poses.
. Neither of the other options will achieve a similar result of
reducing the toxicity of the waste. Hence, particularly over
the long term, EPA's treatment-based remedy is significantly more
reliable than either alternative option. In short, the major
reason EPA has decided to treat the wastes is that the Agency
believes that this remedy will do the best job of protecting
human health and the environment.
EPA's decision that a treatment-based approach is the appropriate
remedy for this site is supported by ARARs and by the Agency's
governing statutory scheme. Section 121(b) of SARA requires
that the Agency select treatment-based remedies to the maximum
extent practicable. This extremely strong statutory preference
for remedies that permanently and significantly reduce the ~6xicity
of hazardous substances butt~esses EPA's view that a permanent
remedy is the appropriate solution to the risk this site presents.
This is particularly true given the relatively small size of the
site and the extremely toxic, persistent and mobile character of
many of the hazardous substances located on the site.
Finally, EPA's treatment-based remedy also meets the statutory
mandate of c6st effectiveness. The cost of this remedy is
$14,700,000. Other iterations of the treatment-based remedy
(for example, alternative 15 in the RIfFS provides for
incinerating the VOC-contaminated s01ls as well as the PCB-
contam1nateds01l), would cost cons1derably more.
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FOOTNOTES
1/ Section 4 of SARA provides that unless otherwise specified,
the effective date of the 1986 amendments is their date of
enactment (October 17). Thus, in general, the provisions in
SARA apply wlthout qualiflcatlon to this ROD. Section l21(b)(2)
contalns an exceptlon to this general rule, providing that a ROD
.issued wlthln 30 days of SARA's enactment need only comply with
the section 121 cleanup standards to the "maximum extent
practicable." Because the Agency is not issuing this ROD withln
30 days of SARA's enactment, the section 121 standards apply
without being subject to this "maximum extent practicable"
limitation. In any event, EPA's remedy complies with section 121.
2/ RCRA's Part 265 also contains standards for managing hazardous
waste, but, as the Preamble indicates, 1t 1s the Part 264 standards,
which are deslgned to be RCRA's ultlmate standards, which gulde
CERCLA remedial actions. .
If hazardous waste remalns at the facillty after closure,
"post closure" care requ1rements are triggered for several "types
of RCRA facilities. These "post closure" requirements also may
be relevant and appropriate to the circumstances of a Superfund
s.lte.
3/ As noted above, the RI/FS's f1nal screen1ng d1scussed s1x
opt10ns. Three of these opt1ons are essent1ally those d1scussed
above. Two of the remaining three are variations of the three
discussed above, whlle the final alternatlve ~rovldes for disposing
of all of the contaminated soil off site.
4/ 40 C.F.R. Subpart F provides that levels should be set at a
"polnt of compllance", that ls, at the boundary of the faci11ty.
Th1s approach 1s not appropr1ate 1n a case such as this, where
the Agency has dec1ded to cleanup the groundwater on site.
Concernlng section l2l(d)(2)(B)(ii)'s apparent limited authorlzation
to set ACLs by assuming a point of exposure beyond the boundary
of the facility, th1s prov1s10n allows the Agency, 1n 1ts discretion,
to set ACLs at a point beyond the boundary of the fac111ty. First,
this provision 1s inapposite because on site groundwater contamination
needs to be cleaned up. Moreover, th1s site does not meet the three
condit10ns for sett1ng such ACLs. F1rst, concern1ng the cond1tion
contained in section l2l(d)(2)(B)(1i)(II), based upon the record,
EPA 1s not prepared to conclude that the existing measurements
or project10ns establish that there is or will be no stat1stically
s1gn1f1cant increase of such constituents from such groundwater
1n such surface water at the p01nt of entry or.~t any point
where there is reason to believe accumulat10n of constituents
may occur downstream.
EPA also does not believe that subparagraph (III)'s requirement
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preclude human exposure to the contaminated groundwater at any
point between the facility boundary and all known and proJected
points of entry of such groundwater into surface water can be
met. Exposure to the contaminated groundwater could occur in the
marsh between the site boundary and Pond, in wells that could be
installed along the sides of the marsh, and in the outlet to the Pond.
EPA does not believe that any current measure will preclude
. human exposure in these areas.
In short, EPA believes that Congress intended that ACts using a
point of exposure beyond the facility boundary only be used when
the Agency has a high degree of confidence that all of the three
l21(d)(2)(E)(ii) conditions are present at a site, and when the
groundwater under the site itself is not going to be cleaned up.
Here, EPA does not believe that these three conditions exist, and
it also intends to clean up the groundwater under the site.
Consequently, the Agency believes that setting ACts beyond the site
boundary is not appropriate. Such a position is buttressed by the
State requirement that Route 125 should be the compliance point.
5/ EPA believes that the prQper role for cost effectiveness is in
comparing the cost of different alternatives that would achieve
the same result. For example, both aeration and incineration
would achieve the result of reducing the level of VOCs in the
soil to accept~ble levels, and EPA selected aeration because of the
Agency's belief that aeration would be less costly. It is not
appropriate, or necessary, to compare the cost of aerating the
VOC-contaminated soi15 to the cost of capping these soils, or to
compare the cost of incinerating the PCE-contaminated soils to
the cost of landfilling them, because a cap or landfill would
not achieve the same result as a treatment-based remedy. In
this case, the difference in cost would not be dispositive in
any event.
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OP!:'R.AT UH. A.N D 'IA I NTE!J~~;U:
O~er.itl<)n c1nd nainte'1anc~ (1.>&'\) are thoS,J c:)st.~ raquu-->rl t.)
o~erate and maintain the remerli~l "I.:tinn thr8u::/hc>ut its liE~tirT1e.
This ~ctiviti ensures trl~ liteti'1'\e eft"?ctivenes:- 01: t"e rerT1erlial
alternative selecte~.
The estimat~d C<'lk>itril, 0&11 an<1 iJrAsf~nt wl)rtl1 costs Eor tl,e
recommended alternative are detailed ~n Tables 5 <'Inri ~.
~tate Role
The st~te's role in this feder~l lead sit~ i~ multi~le. The
state reviews documents to determine if they are in com~liance
with aJplicable state laws and ~rovides comments on all EPA
funded studies at the site. The state of New Ham~shire concurs
witt) EPA.' s chOSAn rerneay tor the clean up of t~e O&G/GLCC site
located in Kinyston, r~ew Ham~shire. The State of ~Jew Ham~shire
will kJrovide:
o IlJ \:>ercent ot trle cavit.;l c.osts I)f the chosen remerly
o 10 percent of the operation and ~aintenance costs for
the chosen remedy throughollt the re",8diation process.
o 10 percent of costs associated with the monit~ring of
reiidential ~ells in use otE site f6r the first year.
o 100 ~ercent of costs associated with monitoring of
residential wells and environmental monitoriny in Cnuntry
Pond.
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TABLE 5
Becommended Alternative Cost Summary
Management of Migration Alternative - Groundwater Extract~on
and Treatment
INITIAL CAPITAL COSTS
Extraction Wells
Pumps & Piping
Access Road to Marsh
Treatability Studies
Equalization
Precipitation/Flocculation
Air Stripping
Biological Treatment
Ion Exchange
Air Ouality Monitoring
OPERATION AND MAINTENANCE (O&M) COST
Total annual cost including Pumping,
Maintenance, Labor, etc.
Environmental Monitoring
Present Worth O&M costs
Total Alternative Costs
S100,000
5225,000
5137,500
S62,500
517"5,000
5400,000
S130,000
S250,000
S1,075,000
57,500
S2,562,500
5755,000
S100,000
5855,000
S3,250,000 (Assumes 5 year
treatment)
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TABLE 6
Recom~ended Alternativp. Cost Summary
Source Control Alternative - Aeration (low temperature
thermal stripping) and incineration
INITIAL CAPITAL COSTS
Demolition Pre-Excavation
Site Preparation
Pre-incinerati~n Studies
Aeration Pilot Studies
Incineration System (1)
Aeration System (2)
Site Cover
$300,000
25,000
75,000
175,000
2,430,000
2,625,000
400,000
TOTAL INITIAL CAPITAL COST
$6,030,000
OPERATIONS AND MAINTENANCE
On-Site Treatment System
S i t.e. Ma in tel'\ance
Material ~andling
Monitorinq and Analys~s
TOTAL ANNUAL O&~ COSTS
(O&~)
COST,
$650,000
90,000
50,000
90,000
$ 880,000
PRESENT WORTH O&~ COSTS
S2,400,000
Annual Costs for Post-Closure
Monitorinq Upon Completion
of Remedy(3)
PRESENT WORTH POST-CLOSURE
$100,000
$950,000
*TOTAL ~LTERNATIVES COSTS
$9,380,000
. . *Based on estimated qu~ntity of 19,000 yd3
(i) Costs based on mobile 'incinerator and include all
costs, includinq O&M, in this item.
(2) Costs for this item include excavation and all other
pertinent items for this system.
(3) Costs for this item are based on the ~ssumption that
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SCHEDULE.
Sign Re~ord of Decision.
January 16, 1987
Proje~t design, to in~1ude
treatability studies.
June 1, 1987
Begin construction of on-site
soil treatment fa~ilities and
groundwater treatment system.
Ju 1 Y 1, 198 8
Constru~tion complete.
June 1, 1989
Begin on-site excavation and
groundwater extra~tion and treatment.
August 1, 1989
EPA evaluates groundwater treatment
for 60nsisten~y with remedi~l obje~tives.
August 1, 1994
* EPA would follow this projected s~hedule if this were a Fund
lead site. Due to the pending litigation, it is not ~ertain
that this remedy will be implemented according to this s~hedule.
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COMMUNITY RELATIONS
Throug~~ut the site's history community concern and involvement
has been high. Local concern has focused on the health hazards
associated with the soil and groundwater contamination. Also
there is a wider, regional concern about the contamination of
surface waters, particu1ary nearby Country Pond. The primary
desire among local citizens and officials is that the site be
cleaned up as soon as possible and Country Pond is protected from
contaminants migrating from the site.
Local citizens have organized a group called .We Agree - Save
The Environment, Inc." (WASTE, Inc.). This group has been active
with state and local officials, as well as national organizations
such as the Environmental Defense Fund and the Izack Walton League.
In addition, local and state officials including members of
the Legislative Delegation, the Governor and his staff, and
members of the Congressional Delegation and their staffs,
have been actively involved in and are interested in site activities.
Throughout the RIfFS, EPA and the State of New Hampshire have
been involved in litigation wit~" five ~otentially responsible
parties: International Minerals and Chemical Corporation
(IMC'), which currently owns the GLCC site, and four firms
collectively known as the Generators (General Electric
Company, Lilly Industrial Coatings, Inc., Solvents Recovery
Services of New England, and K.J. Ouinn & Company, Inc.)
A public informational meeting to describe the FS alternatives
was beld at the Kingston Town Hall in Kingston, on September 4, 1986.
The meeting was well attended by citizens, local officials and
legal representatives of potentially responsible parties. On
September 18, 1986 a public hearing was held at the same location
to record comments by any interested parties. Comments were
given by WASTE Inc., Senator Warren Rudman, New Hampshire
State Representative David A. Welch, Hartley Bailey, resident
of Newton Junction, the Town of Newton Board of Selectmen,
Congressman Robert C. Smith, the selectmen of the Town of
Kingston, Mr. Vautier, an interested citizen, International
Minerals and Chemical Corporation (IMC), and Mr. Hannigan,
citizen of Kingston. Written comments were also received from all
of the above mentioned, the four generators and the Town
of Amesbury, Massachusetts Board of Health during the remainder
of the comment period. The formal, three week comment period
to accept oral and written" comments on the feasibility study
alternatives took place from September 4, 1986 until September
25, 1986.
A second comment period was held to receive public comments on the
Preferred Remedy from October 29, 1986 until November 21, 1986.
At the request of community members, EPA extended the public
comme.nt period until December 5, 1986. Written comments were
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.b" . .
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. =: ...
received from WASTE, Inc., International Minerals. and Chemi~al
Corporation (IMr,), the four firms colle~tively known as the
Generators (General Electric Company, Lilly Industrial Coatings,
Inc., Solvents Recovery Services of New England, and K.J. Quinn
and Company, Inc.) and the fi~ of Bracken and Baran, representing
Senter Transportation Company, Inc., Concord Realty Trust, Bernard
Senter and Sally Senter- owners of part of the Ottati & Goss/Great
Lakes Container Corporation Site.
Comments received during the comment periods and EPA's responses
are included in the.attached Responsiveness Summary. The Respon-
siveness summary also contains a section on remaining community
concerns, which summarizes questions the community raised during
the RI/FS process, but were not submitted as formal comments.
These are concerns that the EPA and the State should be aware of
as they prepare to undertake remedial design and construction at
the Ottati & Goss/Great Lakes Container Corporation Site.
Both WASTE and the Kingston Health Department (KHD) requested
that an alternative water supply and additional wells be
in~talled down gradient of the site for groundwater extraction- .
and treatment to prevent migration of contaminants into
private water supplies. WASTE and KHD believe these two
actions should take place immediately, and be funded with
emergency response funds.
u.S. Representative Robert C. Smith commended the FS objectives
and emphasis on achieving permanent treatment. He stated his
support for the request that a health study be conducted. He
also urged EPA to take steps to ensure the quality of public
health and to continue to monitor the water quality status
for residential wells and Country Pond.
u.S. Senator Warren Rudman stated his support for the community
efforts at the site and urged EPA to cleanup and treat soil
and groundwater, implement a health survey and provide an
alternative water supply where necessary.
u.S. Senator Gordon J. Humphrey stated it is time for EPA to
take a~tion in the implementation of a remedial plan. Senator
Humphrey urged EPA to give thorough consideration of the
recomendations of WASTE.
New Hampshire State Representative David A. Welch stated his
full support for the recomendations of WASTE and urged all
possible haste in actions to protect the public hea~th and welfare.
The Town of Amesbury, Massachusetts expressed concern with the
procedures which will be used to control the potential pollutant
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release during. the final remedial action steps. The town proposed
that a monitoring network be established throughout the downstream
waterways to ensure the quality of the water supply.
Mr. Hartley Bailey of Newton Junction, New Hampshire expressed
concern that fish tested in Country Pond for contamination in 1984
and 1986 have not been tested for VOCs. Mr. Bailey stated that
su~h tests would give a better indication of the depth of VOCs
than the surface tests for VOCs which have been previously perfor-
med. Mr. Bailey a1so stated that state officials had promised to
conduct VOC tests on the fish tested for other contaminants in
1986 but have failed to keep that promise.
h
Mr. Charles Hannigan of Kingston, New Hampshire urged EPA
to take action and clean up the site. Mr. Hannigan expressed
concern that too many studies, and not enough action, had
taken place.
Mr. Duke Vautier of Pelham, New Hampshire commented that
incineration below 35000F leaves contaminated ash. Mr. Vautier
suggested that EPA consider a pyrolysis process that would.
exceed SOOooF.
u
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ENFORCEME~T ANALYSIS
. .
The Ottati , Goss site is currently in litiqation. The United
States filed a comr'llaint on ~~ay 18, 1980. The court bifurcated
the trial. ~ 116 day trial on liability took place between
December 5, 1983, and Jun~ 13, 19R~. T~ its decision dated
December 9, 1985, t~e Court conclu1ed that the following defendants
are liable for some or all of the hazardous substances present at
the site:
Great Lakes Container COrPoration
International Minerals' Chemical
Louis Ottati Sr.
t'lellington Goss
Ottati , Goss, Inc.
Geochem
Senter Transportation Co.
General Electric Co
Concord Realty Trust
Bernard Senter
Sally Senter
K . .7. Qu inn Co.
Lewis Chemical Co.
Solvents Recovery Service of New
Lillv Industrial C~ating~, I~c.
Corporation
Enqland
The Court has scheduled the trial onrem~dy and da~aqes to beqin
on February 2, 1987. The Unite~ States has had some preliminary
settlement discussions with various defendants. It is ~ot
possible at this point to predict whether or when the Uniten
States will achieve a settlement with one or more of the defendants.
~
v
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,Octnher 27, 19~n
.
~p.missit'lle p~ c~ncentrAtion in soil, ~.tati , I.oSS/r.t.ee, Kinostnn, NH
. P'11. ~ . t 1
r:.-:r~..m 'I'siU, Se. 0., ...IIVlrClnMPn! 'Ibxicolooist
~ater Supply Pranch
Paul Marchps~ault, Site Manacer
Superfun~ Branch
This is the fo11()'to1 up to our meetina ()f 10/23/86 r~ax:rlina thP. derivatinn
of a rermis~ih1e PCR cnncpntration in ~il for the scurce arp.as c1~an-up
at the Ottatj & ('".,ossJc;t.ee site. '!hi!; men.., inclu~es clarification for
concerns raised in the mPetino.
~sic asslrnptio~s use~ in the calculati6n are: the ~st susce~ti~le ~ula-
tinn at risk of ex~sure are l.~ - 4 year n1~ ~h5l~rp.n ~n~ sni1 inne~tinn
is c"nsic1ered the 1"I!.;nr co~trih\ltt:)r lIl'mMO ,,]1 ~ssihle r()ut.es ()f e)C~UTe.
A..c;s:ui-\ino thp cleal"l-up oC')al is ~n increM!ntal Hfeti~ cancer risk ~f In-5,"o
the ~rMi~~ible ~ co~centration in soil fnr.re~i~ential area is '0 ~~.
AJternat.ivelv, if thi~ sit~ is consi~er~ as a non-re~irlentjal area anc1 t~
freauency ()f eXJX>~u:'e for chi1c1ren visitina the are! of cnnta",jnate<1 snil
is as!;\~d t.c be 70 ~~ys ~r year (twice aw~k for. 3~ wep.ks P.xclurli~
inclp.~nt weather), th~ ~~i~~ihlp. PCB concentration in soil is a~pr9xi-
r.'.atelv 70 f')fT'\.
In-5
~. 3( ); C.2 c/r:ay x 10-.) o/Ka x 30% -:-- 17 k~ x 245 ~ays/365 cays x 3. 5 yr/7.~ yr.
-
20MTo'
where:
10-'5 ~ AsSUM." J ife~51'1E canc\!r ri,,)" :'pvel for cJecJn-un
(:Joal
4.34: Cancer risk mtencv f()r PCR eX1"res~ec1 a!=
(TTQ!ko/day) -.L .
0.2 Q/day: D8ily soil inoestion (nnt anplicahJe to children
wi th T'ica) .
10-3 C'J,IJ(Q: Conversion C\f 0 to ICq of R()il inaest.ion
30\: A"'S(')t'J'tion rate nf PCR in ~oil frr.n GI tract
17 Y.o: Average hcrly wp.iaht f~r 1.5 - 4 vears old
245/365: Yearly freauency nf eXfY)sure ( 35 wMks oer year
. excludiM9 incJeJ'IP.nt weather)
3.5/70: Fraction of the lifet~ fnr ~tential e~ure
~ince exnso~Jre throuch dennal at'\so~tiC")n I'm "inhalatim (of PeR in 8.'7\hient
air a~ ~ir ~rticulates) are not inco~r"t~ in t~e caJculatinn, the
pemis~ihle PCR CClncent.rat.inn in soil could he ]("AoIP.red than whAt is or....
~entp.~. C'l')!!'IT'Ared to soil i.noe~tinn, deT.Jl'al ahsnrntion C")f ~ frm cnn-
- tn~in~te~ s~il i~ cnnsi~ered' in~innificant. Inhalation ()f Pr.R p'~jtted from
. cC')nt.amini'ter1 ~il tn the &""''''ient air anti ~usf')P.med particu'ates mioht .
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