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r
"
'-'
9
n 0 ' ~
U '-tLf
-36-
wlth the cancer potency factor. These risks are probabilities that are
generally expressed in scientific notation (e.g., 1x10-6 or 1E-6). An excess
lifetlme cancer risk of 1X10-6 indicates that, as a plausible upper bound, an
lndlvldual has a one in one mlllion chance of developing cancer as a result of
slte-related exposure to a carclnogen over a 70-year llfetime under the
speclfic exposure conditions at a site. The Agency considers indivldua1 excess
cancer rlsks ln the range of 10-4 to 10 -6 as protective.
Potentlal concern for noncarcinogenic effects of a single contaminant in a
slng1e medium is expressed as the hazard quotient ("BQ") (or the ratio of the
estlmated intake derived from the contaminant concentration in a given medium
to the contaminant's reference dose). By adding the HQs for all contaminants
withln a medium or across all media to which a given population may reasonably
be exposed, the Hazard Index ("HI") can be generated. The BI provides a useful
reference point for gauging the potential significance of multiple contaminant
exposures within a single medium or across media.
Estimated total incremental lifetime cancer risk from future household use of
groundwater using present conditions was calculated for wells GH-S, 13 and
GHP-5. These wells are located on the appro~imate center line of the
downgradient plume and are positioned between the northern boundary of the
disposal area and the edge of Pugh and clover creeks.
The risk and hazards from individual chemicals show that the calculated risks
and hazards are related primarily to the presence of carbon tetrachloride which
accounts for over 90\ of the total risk and hazard at each well.
The chemicals of concern at the site are primarily liver toxicants and as such
it is appropriate to sum the incremental risks and hazards for the several
primary chemicals reported in groundwater. since the exposures would all
relate to the local population, it is also appropriate to sum the risks from
the two household uses of groundwater, namely drinking and bathing. The total
incremental risks and hazard presented by household use of the groundwater are
summarized in Table 8 based on level 1 assumptions (see page 26). It is
apparent that the risks and hazards all exceed acceptable levels by several
orders of magnitude. This is to be expected since the reported concentrations
exceed Water Quality criteria for drinking water by several orders of magnitude
and the Health Advisories for drinking water by 2 to 3 orders of magnitude.
The additional lifetim8 risk of cancer and the non-carcinogenic hazard from
exposure to surface waters of the creeks based on the site-specific indicator
chemlcals are 8ummarized in Table 9.
In the 8ingle instance where the assessment shows unacceptable risk from
surface water (eating fish from Pugh creek, P3a), the risk is almo8t totally
from the reported level of PCBs which is probably not originating from the
site. As discussed earlier, the reported concentrations of pesticides, PCBs
and phthalates are apparently from background sources or are analytical
artifacts, and are not considered to be Site-related. The reported
concentrations of organic solvents in the ROund 2 creek samples co~ld
rea80nably be Site-related although the upstream sample from location C2a has
the highest concentration of carbon tetrachloride reported in clover Creek.
...

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5
9
0045
TABLE 8
St.iMMARY OF CA~CER RISK A~D HAZARD [~DEX
AVERAGE EXPOSL"RE SCE~ARIO ill
GROt:~DWATER I="i DOW~GRAQ[E~'" PlL~E
HARDE~A.\l COt:~'TY LA~DFILL RL'FS
  Cancer Risk Ha:ard [ndn
Well I.D. Round I Round 2 Round I Round 2
On-Site Average 1.4E.ol 1.1E+OO UE+04 1.1E.OS
C\o1-S 4.2E.ol 1.8E+OO 4.4E+04 1.9E.OS
1~ 3.9E.ol 7.7E-ol 4.1E+04 1.:!.E+OS
CMP-S 3.3E.ol 4.7E.ol 3.SE+04 4.9E+04
(1)
Average exposure scenario is the Level 1 scenario for future
household use fran current carbon tetrachloride and chloroform
levels in grourdwater
,.

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-3.3-
5 9
0046
TABLE 9
SUMMARY OF CANCER RISK AND HAZARD INDEX
AVERAGE EXPOSURE SCENARIO (1)
PRESENT REPORTED CONCENTRATIONS
SURFACE WATER IN CLOVER AND PUGH CREEKS
HARDEMAN LANDFILL SITE RifFS
Welll.D.
Cancer Risk
Round 1 Round 2
Hazard Index
Round 1 Round 2
Clcn'er Creek
C2a Cpstream
C2 Upstream
C3b
C4
O.OE+OO
1.4E-06
O.OE+OO
4.0E-05
1.3E-07
4.7E-08
~A
8.1 E-08
9.5E-02
3.9E-02
3.2E-05
3.8E+00
1.4E-02
5.1 E-03
NA
8.9E-03
Pugh Creek    
P2a Upstream 7.0E-08 NA 1. 9E-01 NA
P2b Upstream O.OE+OO NA 1.9E-01 ~A
P3a 3.3E-03 NA 5.6E-01 NA
P4 1.4E-07 1.6E.07 2.1E-01 1.7E-02
P5 3.3E-07 6.5E-06 3.6E-01 4.2£-01
P6 O.OE+OO \lA 9.5£-02 \!A
;..; otes:
~ A - Not Analyzed
(1) A verage Exposure Scenario is the Levell Scenario
....

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0047
-39-
Assuming the carbon tetrachloride is Site-related, examination of the risk and
hazard assessment results show that the reported concentrations do not present
a concern for fish consumption or for occasional skin contact. The swimming
exposure component of the assessment calculations would greatly exceed any
casual skin exposure component related to wading or fishing.
Based on the results of the risk calculations, it is evident that the potential
exposure to volatile compounds in the air due to specific chemicals
volatilizing from the surface waters while fishing does not represent a
significant risk to the general public.
By the application of appropriate modeling techniques, water concentrations of
carbon tetrachloride and chloroform were predicted in the wells downgradient of
the landfill and in the creeks. Values predicted for the years 1995, 2000 and
2020 in Wells GM-5, 13, 7, and GMP-5 were evaluated for potential total
incremental lifetime cancer risk and non-carcinogenic hazard using the same
household exposure or recreation scenarios as were used for evaluation of
present conditions. The summary data are presented in Tables 10 (groundwater)
and 11 (surface water).
.
Upon examination of. Table 10, it is apparent that the estimated risks and
hazards are still far in excess of acceptable levels, even in the year 2010
after an additional 20 years of migration of the plume without further
remediation.
The predicted concentrations of carbon tetrachloride and chloroform in clover
Creek are estimated to peak in the year 1994. Table 11 shows a gradual
decrease of estimated potential risk and hazard after the year 1995. At the
estimated period of peak flux to the creek between the years of 1993 and 1995,
estimated potential risks are below the target range of 1E-04 to 1E-06
estimated total incremental lifetime risk of cancer. The estimated total
hazard level is also below a level of concern even applying the more
conservative conditions of 3Q20 creek flow where the estimated groundwater flux
from the plume area makes up approximately one-half of the total creek flow.
Uncertainties
Regardless of the type of risk estimate developed, it should be emphasized that
all estimates of risk are based upon numerous assumptions and uncertainties.
In addition to limitation. associated with Site-specific chemical data, other
assumption. and uncertainties that affect the accuracy of the Site-specific
risk characterizations result from the extrapolation of potential adverse human
health eff.ct. from animal studies, the extrapolation of effects observed at
high-dose to low-dose effects, the modeling of dose response effects, and
route-to-route extrapolation.
The use of acceptable levels (established standards, criteria and guidelines)
and unit cancer risk values which are derived from animal studies introduces
uncertainty ,into the risk estimate.. In addition, the exposure assumptions
used in estimating individual dose levels are often surrounded by
uncertainties. As such, the.e estimates should not stand alone from the
various assumptions and uncertainties upon which they are ba.ed. In developing
numerical indices of risk, an attempt i. made to evaluate the .ffect of the
a.sumptions ,and limitation. on the numerical ..timat...
~

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We/ll.D.
C\-1-5
CMP-5
(1 )
-_.1-
5
9
0048
TABLE 10
SL'MMARY OF CASCER RISK A:-';D HAZARD ISDEX
F1.rn.:RE ESTI~A TED CO:-';CE:\'TRA TIO:-.;S
GROL"NDWATER IN DOWNGRADIE:-';T PLL~E
HARDE~AN U.:-';DFILL SITE RI/FS
13
Cancer Risk (1)  Ha:ard Index 
2995 2000 1020 1995 1000 2.010.
1. :""E.OO 1.0E.00 -4.:2£-01 1.8E.05 1.1:: ...05 .UE...V4
l.4E.OO 8.9E-01 3.7E-01 UE.05 9.3E.04 3.8E.04
1.1E...00 9.0E-01 4.:£-01 1.1E...05 9.4E.04 4.4E...04
8.4E-01 7.7E-01 3.9E-01 8.9E.04 8.0E.04 4.1E.04
Risk estimates presented for the average (level 1) scenario for
groundwater exposure fran dri.nk~ and bathing exposure to
carbon tetrachloride and chloroform
,.

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0049
TABLE 11
StiM.'-fARY OF CA='iCER RISK A~D HAZARD {;...1)EX
Ft.JTt"RE EST1~ATED CO~CE~TRAT10~S
St"RFACE WATER I~ CLOVER CREEK
HARDE~A~ LA~DFlLL SITE RI/FS
 Cancer Risk!I)  Ha:ard Index(2)
Welll.D. 2995 2000 2020 1995 2000 2020
Carbon Tetrachlonde 3.iE.Q7 3.~E.Q7 1.8E-07 6.9E.Q1 5.9E.Q1 3.2E.Ql
Chloroform 1.5E.Q9 1.2E.Q9 5.5E-10 5.9E.Q3 ~.5E.Q3 2.0E.Q3
T 01315 3.7E.Q7 3.2E.Q7 1.3E.07 6.9E-01 5.9E.Ql 3.3E.{)1
(1 )
~dative cancer risk. based on level 1 exposure assumptions
for all relevent pathways
(2)
Hazard i.n:iex based on "3Q20" estimates
. .
. '.

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7he uncertainty factors which are incorporated into the risK estimates are
bel~eved to be conservative. As such, when they are considered collectively,
exposure and subsequently risK may be overestimated. On the other hand, these
es~~mated risk calculations were based on present conditions at the Site,
~ncluding the cap, and no maJor ~ncreases of contaminants already in the
aqu~fer. Additional risK could occur should the concentrations increase or the
cap erode.
In conclusion, based on the results of the risk assessment, actual or
threatened releases of hazardous substances from Site, if not addressed by
~mplementing the response action selected in this ROD, may present an imminent
and substantial endangerment to public health, welfare, or the environment.
Environmental RisKS
As previously stated in this ROD, the final potential environmental risks
associated with the site will be addressed as part of the second operable unit.
Previous studies have generally indicated that the contaminants migrating from
the Site are not presenting an environmental risk since the contaminants are
highly volatile and do not concentrate or bioaccumulate in the environment.
However, additional studies concerning these waste. and the more persistent
compounds located in the di~posal areas are required for a final analysis.
Also, although previous investigations have not identified any endangered
species in the area of the site, it has recently been determined, and will have
to be verified, that an endangered species of bat may exist in the vicinity of
the site.
DESCRIPTION OF ALTERNATIVES
The surficial aquifer is under consideration for remediation due to the
.unacceptable risk associated with the con8umption of the contaminated
groundwater.
Based on the contamination detected in the aquifer at different locations, the
groundwater has been divided into two areas: on-site and off-site. The on-site
groundwater i8 that portion of the aquifer located directly beneath the
disposal areas. The off-.ite groundwater is that portion of the aquifer
located beneath all properties surrounding the dispo.al areas. The off-site
groundwater contains mainly the highly mobile contaminant. like carbon
tetrachloride and chloroform. The following is a list of the remedial
alternative. under con.ideration for the contaminated groundwater. The FS
Report contain. a more detailed evaluation of each alternative.
1 )
No action (A1 and B1 in the FS).
2 )
On-site Groundwater Extraction through well., Treatment, and surface
Water Discharge (A4 in the FS).
3 )
In.titutional Control. (B2 in the FS).
4 )
Off-site Groundwater Extraction through well. and a collection
trench along pugh and Clover creek., Treatment and Surface Water
Di.charge (B4in FS).
..

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,..,-.r-1
UU;)
-43-
5 )
Off-site Groundwater Extraction through a' collection trench along
Pugh and Clover creeks, Treatment anet surface Water Discharge (86 in
FS) .
6 )
Off-site Groundwater Extraction through wells, Treatment, and
Surface Water Discharge (88 in FS).
It should be noted that groundwater reinjection was considered in the FS for
each of the groundwater ,treatment remedies. However, groundwater reinjection
is' not considered feasible due to concerns over the ability of the aquifer to
accept all of the reinjected water, the affects of the reintroduced water on
contaminant flow, and the long-term maintenance of the injection wells, which
may plug up over time due to mineral precipitation.
All of these alternatives except -No Action- involve restrictions on land:and
well use in the vicinity of the site, upkeep of the fence arid property, and
monitoring to assess the effectiveness of the' remedy. Each alternative also
includes identifying and evaluating possible additional remedial actions
required for addr~ssing the contamination of the entire Site including the
contaminant source (the disposal areas) and posslble environmental/ecological
concerns.
ALTERNATIVE 1: NO ACTION
pre.ent Worth (PW) cost $0.00
Years to Implement: 0
CERCLA requires that the -No Action- alternative be considered at every site.
Under this alternative, no groundwater containment or treatment would take
place. The only reduction of contaminant levels would occur via natural
processes such as dispersion and attenuation. since moni1;oring' is already part
of the disposal areas maintenance, additional cost would not be incurred.
ALTERNATIVE 2: ON-SITE GROUNDWATER EXTRACTION. TREATMENT AND SURl"ACE
WATER DISCHARGE
Present Worth Cost: $7,266,000
PW capital cost: 3,146,500
PW O'H Cost: 4,120,000/30 yr.
Years to Impl8JD8nta 2
Alternative 2 provides for tbe hydraulic containment of the contaminated
on-site groundwater along tbe nortbern boundary of tbe disposal areas. ,
Approximately 5 extraction vells would be installed to,develop a bydraulic
gradient along tbis northern boundary line preventing on-site groundwater
contamination above HCLs fraa leaving tbe dis~sal areas. Extracted on-site
groundwater would be pumped to a treatment system located on the site property
for treatment of groundwater to National pollutant Discbarge Elimination Syst..
C-NPDES8) concentrations establisbed as part of the clean Water Act for surface
water discharges. The contamination, particularly carbon tetrachloride,
chloroform, and naturally occuring matals, would be treated using settling
tanka for solids removal, air stripping and carbon adsorption. Treated
,.

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on-site groundwater would be di~charged to one of the nearby surface water
bodies (Pugh or clover Creek) and would comply w~th NPDES discharge
requirements.
ALTERNATIVE 3: INSTITUTIONAL CONTROLS
Present worth Cost: $1,088.00
PW capital Cost: 60,000
PW O&M Cost: 1,028,000/30 yrs.
Years to Implement: 50
Alternative 3 provides only for the restrictions of land and groundwater use In
the contaminated areas. It includes the monitoring of the contaminat~on and
its migration off-site. Reduction of contaminants to acceptable levels would
occur only through natural processes and will require an estimated 50 years
before cleanup goals would be met.
ALTERNATIVE 4: OFF-SITE GROUNDWATER EXTRACT:ON THROUGH WELLS AND A COLLECTION
TRENCH ALONG PUGH AND CLOVER CREEKS. TREATMENT AND SURFACE WATER DISCHARGE
Present worth Cost: $11,791,500
PW capital Cost: 6,568.500
PW O&M Cost: 5,223,000/30 yrs.
Years to Implement: 2
Alternative 4 addresses the containment and recovery along Clover creek and the
extraction of off-site groundwater in the areas of highest contaminat~on. A
slurry wall and collection tile system would be placed along clover creek
station at the confluence of clover creek and pugh creek for approximately
8,000 feet (see Figure 16) to the western limit of the plume to collect
contamination already entering the creeks.
Approximately 10 extraction wells would be installed into the high
concentration areas of the off-site groundwater to control further migratlc~ cf
the plume toward the creeks and to treat the groundwater to MCL concentra~lon
levels. The extracted water would be pumped to an off-site system for
treatment. The system would consist of settling tanks, air stripping and
carbon absorption. Treated groundwater would be discharged to one of the
nearby surface water bodies and would comply with NPDES discharge requ~rements.
ALTERNATIVE 51 OrF-SITE GROUNDWATER EXTRACTION THROUGH A COLLECTION TRENCH
ALONG PUGH ~ CLOVER CREEKS, TREATMENT AND SURFACE WATER DISCHARGE
Present worth cost: $9,384,000
PW capital Cost: 4,727,000
PW O&M Costs: 4,657,000/30 yrs.
Years to Implement: 2
Alternative 5, like Alternative 4, addresses the containment and recovery ~~
off-site contaminated groundwater along clover Creek. A slurry wall and
collection tile system would be placed along Clover creek; however, no

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LEGEND
----
APPROXIWA TE: UW'TS OF PLUWE
COI.J.£CT1ON DRAIN AUGNWENT
~: . :..;. .:
CJ:..:.::.:-:-:'. :.~:'.
"

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9
f"\u~rl.
u. :) {~
-46 -
extraction wells would be installed in the high concentration areas of the
groundwater plume, The contaminated groundwater would be treated and.
discharged in the same manner described in Alternative 4,
ALTERNATIVE 6: OFF-SITE GROUNDWATER EXTRACTION THROUGH WELLS. TREATMENT AND
SURFACE WATER DISCHARGE
Present worth Cost: $4,378,000
PW capital Cost: 1,936,000
PW O&M Cost: 2,442,000/30 yrs,
Years to Implement: 2
Alternative 6 provides for the removal of contaminated off-site groundwater
from the plume in the areas of highest concentration. Approximately 10 wells
would be installed into the high concentration areas of the off-site plume to
control the groundwater contaminant migration and remediate the off-site
groundwater to MCL concentration levels. The off-site groundwater treatment
and discharge would be the same as Alternative 4 and would comply with NPDES
requirements.
~
Any remedy implemented for OP unit t1 shall meet the performance standards set
forth below which are the Applicable or Relevant and Appropriate Requirements
("ARARS") identified for these remedial alternatives.
Remediation of contaminated groundwater for a Class IIa aquifer is required to
meet MCLs as established under the Safe Drinking Water Act (40 CFR 141, 143)
and, if possible, to attain Maximum contaminant Level Goals ("HCLGs"). HCLGs
can not be enforced as cleanup levels since they are sometimes technically
impossible to meet; however, groundwater sampling will monitor for HCLGs as a
possible result of the groundwater extraction and treatment. The groundwater
remediation levels for the contaminants of concern in the aquifer are
identified in Table 12. Reduction of the contaminants to the8e levels will
reduce the risk posed from the consumption of contaminated water from an
absolute risk over a ten year period to a risk of 8.2 X 10-sfor a 70 kg adult
over a iifetime (70 year.). Thi. ri8k falls within EPA's acceptable risk range
of 10-4to 10-6.
Any discharge to a nearby .urface water body is required to meet NPDES
standards e.tablished by the clean Water Act and regulated by the State of
Tennessee. Pugh and Clover creeks are classified for fish and aquatic life,
recreation, irrigation, live.tock watering and wildlife. The allowable
in-stream contaminant levels based on State and Federal regulations are
identified in Table 13. Final discharge levels will be determined by surface
water flow information, contaminant levels, and biological testing that will be
established by the state of Tennessee. The surface water discharge will be
required to meet the NPDES limit8 that are e.tabli.hed.
since contaminants are presently still leaching from the disposal areas, a
Point of compliance, as defined under regulation. promulgated pur.uant to the
Re.ource con.ervation. and Recovery Act ("RCRA") (40 CrR section 264.95) i8
relevant and appropriate for determining the point or line on the site beyond
which contaminant level8 in the groundwater must be remediated to HCL8. The
..

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9
0055
'!'ABLE :2
GROUNDWATER REME~:A'!':ON LE'JELS ~OR
CONTAMINANTS OF CONCERN AT THE
VELSICOL/HARDEMAN COUNTY NPL SITE
CONTAMINANTS   GROUNDWATER   
OF CONCERN   REMEDIATION LEVEL ( 1) MCLG(2) RISK(3)
    (mg/1)  (mg/1) 
VOLATILE ORGANICS      
Acetone   0.7 (4)  
Carbon Tetrachoride   0.005  0.0 1. 9x10-S
Ch1orobenzene   0.1  0.1 
Chloroform   0.006 (5)  1. OxlO-6
Methylene Chloride   0.005  0.0 1. lx10-6
Tetrachloroethene   0.005  0.0 7.SxlO-6
Toluene   1.0  1.0 
Xylenes   10.0  10.0 
~       
Bis (2-ethylhexyl) phthalate 0.004  0.0 1. 6x10-6
Di-n-butyl phthalate  0.7 (4)  
Di-n-octyl phthalate  0.14 (4)  
2,4 - Dichlorophenol  0.1 "( 4)  
PESTICIDES      
Endrin   0.0002 (6) 0.0002 
Endrin Aldehyde   0.0002 (6) 0.0002 
Endrin Ketone   0.0002 (6) 0.0002 -
Heptachlor   0.0004  0.0 5.2xlO-S
       --------
TOTAL CARCINOGENIC RISK    a.2xlO-S
(1) Maximum Contaminant Levels (MCLS) as promulgated under the Safe
Drinking Water Act (40CFR 141,143) were used as the remediation
level for all contaminants that have an MCL. Contaminants without
MCLs are identified numbers, and the source of the remediation
level is identified in the footnotes.
(2) MCLG - Maximum COntaminant Level Goal. A non-enforceable
concentration of a drinking water contaminant that is protective of
adverse human health effects and allows an adequate margin of
safety.
(3) Ri8k is calculated for the carcinogenic compounds
(4) Lifetim8 aealth Advisory (LHA). A lifetime exposure concentration
protective of adverse, non-cancer health effects, that assumes a
relative source contribution (RSC) of 20' of the contaminant in a
drinking water source. (January 31, 1991, Federal Register, page
3535.)
(5) Level set for a lifetime risk (70 years) of 10-6 (one in one
million exces. cancer risk level for drinking water).
(6) On July 25, 1990, a MCL and MCLG of 0.002 mq/l was proposed but is
not final for endrin. Should the MCL be made final, 0.002 mg/1
will be the endrin remediation level. The other endrin compounds
are based on the level set for endrin.
.

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"0 r"" 6 
U :J
-:- .i.5~= J.:3
PLAMNING LIM!TS-:~S7R~A~
VELISCOL CHE~!CAL au~~, ~AR:E~A~ CCUNTY
The following instream limits are orov~ded for planning
pu~~oses and are valid for one year. Ary limits to be
included in a discharge per~i~ ar~ sJcje~~ to t~e ~~b:i~
~o~ice ~rocess, t~e exact locatio~ of t~e disc~arge and t~e
relative size of the discharge.
Compounds
VO~ATIL.~S
Acetone
Benzene
Carbon disulfide
Car~on tetrach: o~ ~ :~.
Chlorobenzene
Chloroform
Methylene chlorice
Tetracnloroet~er.e
Toluene
Tr-ichloroethene
Xylenes
Bis(2-ethylexyl)ph~~a1ate
Di-n-butyl phtha~ate
Di-n-octyl phthala~e
2/4-Dichlor-opheno~
Naphthalene
Dieldrin
Endr-in
Endr-in Aldehyde
Endr-in Ketone
Heptachlor
Aluminum
Arsenic
Barium
Cadmium
Calcium
Chromium VI
Total
B~As
P~ST!CIDES
"'E~AL.S
Copper
Iron
Lead
Magnesium
Manglnese
Mercury
Nickel
Potassium
Selenium
Silver
Sodium
Zinc
... Technology based limit ap~lies
~ ':J ~ ~e
,
:~st;ea~ limi~, ~g/L.
(chr"onic/a~u~e)
0.CC5*
0.005/C.044
47.0
16.0
0.088
0.010*
0.005/0.807
0.010.
0.059
~ 2 . 0
- 6 .
1.9x10 /0.0025
2.3)('0-6/0.000~8
-

2.0x~O-6
0.087/0.75
0.19/C.36
0.0007/0.002
0.0"/0.O~6
0.01 chr-onic
0.007/0.009
1.0/2.0
0.001/0.034
-

1.2x10-5/0.0024
0.088/0.79
0.005/0.020
0.001 acute
0.059/0.065
discharge.

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OuS7
Point of compliance ("PCC") for this ROD is established by identifying the
disposal areas and setting the POC at the edge of these areas as shown ~n
Figure 17. Due to the steep relief along the edge of the disposal areas at
th~s site especially along the northern and eastern sides, the POC is set at
the base of the grade of the disposal areas.
Land Disposal Restr~ctions ("LDRs") as set forth in regulations promulgated
pursuant to RCRA (40 CFR Part 268) may be applicable to the residuals of the
groundwater treatment facility, spec~fically the sludge from the settling tanks
wh~ch may requ~re RCRA disposal. spent carbon from the treatment process
should be able to be regenerated for additional use.
The Clean Air Act is an ARAR for the releases to air from the air stripper.
Releases from the stripper will comply with Federal and State Clean A~r
Standards.
Any work performed in the area of Clover Creek could affect the wetlands along
Clover creek, and 40 CFR Part 6, Appendix A concerning responses in a wetlands
would apply.
SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
The remedial alternatives developed during the site FS were evaluated by USEPA
u8ing the followi~g nine criteria. The advantage. and di.advantages of each
alternative were' then compared to identify the alternative providing the best
balance Among the.e nine criteria.
1.
overall protection of Human Health and the Environment addresses
whether or not an alternative provide. adequate protection and
describes how risks are eliminated, reduced or controlled through
treatment and engineering or institutional controls.
2.
Compliance with Applicable or Relevant and Appropriate Requirements
(ARAR.) addre8ses whether or not an alternative will meet all of the
applicable or relevant and appropriate requirement. or provide
ground. for invoking a waiver.
3.
Long-term Effectivene..
alternative to maintain
environment, over time,
ability of an
health and the
been met.
and Permanence refer. to the
reliable protection of human
once cleanup objective. have
4.
Reduction of Toxicity, Mobility or volume i. the anticipated
performance of the treatment technologies an alternative may employ.
5.
Short-term Effectivene.. involve. the period of time needed to
achieve protection and any adver.e impact. on human health and the
environment that may be po.ed during the con.truction and
implementation period until cleanup objective. are achieved.
6.
Implementability i. the technical and admini.trative fea.ibility of
an alternative, including the availability of good. and service.
needed to implement the .olution.
.

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.. DISPOSAL. AREAS
. APPROXIW. T! L.OC. TlON
OF I/ELSICOL DEE? 't\t:LL
--- STUDY AREA
-.- DISPOSAL. SITE
a
?E~5:~NEL. SUPPORT z:~~
_. _. - - .-
~. ..;~~ -
....... -
Point of Compliance
=':'i\-: '7" ~Y.?:":.:"'.
..

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5
9
- .
(""'\ -, r ()
LJU-J
7.
Cost lncludes capital costs, as well as operation and malntenance
costs.
8.
Agency Acceptance lndicates whether, based on its review of the
RIfFS and Proposed Plan, TORE agrees wlth USEPA on the preferred
alternative.
9.
community Acceptance lndicates the publlc support of a given
alternatlve. ThlS criterla is dlscussed in the Responslveness
swnmary.
Table 14 contains an evaluation and comparison of
the groundwater using seven of the nine crlteria.
Acceptance are discussed below.
the six (6) alternatlves for
State and communlty
State Acceptance
TOB!: has assisted USEPA in the review of reports and Site evaluations. TOBE
has reviewed and concurs with the selected remedy for the groundwater (see
Appendix B).
Community Acceptance
Community response to the alternatives is presented in the aesponsiveness
summary (Appendix A) which addresses comments received during the public
meeting and public comment period. Although the public had general questions
concernlng the remedy, no comments were received that indicated the need for a
major change in the remedy selected.
SELECTED R1!:MEDY
The selected remedy for the contaminated groundwater is a combination of
Alternatives 2 and 6. This remedy involves the hydraulic containment of the
on-site groundwater using extraction wells to prevent the on-site groundwater
above HCLs from leaving the disposal areas and the extraction of cont&mlnated
off-site groundwater to remediate the contaminated aquifer beyond the POC down
to HCLs. After groundwater is extracted, it will be treated and then
discharged to a nearby surface water body (Pugh or Clover creek).
The selected remedy will include the following:
i)
Extraction wells (approxim£tely five (5») and pumping systems wlll
be inltalled to achieve an effective hydraulic capture of
contaminantl in on-lite groundwater at the POC (see Page 46).
Approxim£te locationl of these extraction well. are .hown in Figure
18; however, locations of these well. will change to comply with the
POCo It i. e.tim£ted that the.e well. mu.t collectively recover
approxim£tely 200 qpm to achieve hydraulic containment. Piezometers
may be in.talled within the projected containment area to
demonstrate capture.
ii)
Extraction well. (approxim£tely ten (10» and pumping IYlte~ will
be in.talled to restore the contaminated off-.ite groundwater beyond
the POC to within acceptable drinking water standards by removlng
groundwater from the areas of peak contaminant concentratlon. :t
...

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TABLE 14:Evaluation o' Groundwater Remedial Alternatives
(J1
'-0
Ev8lual1on C.U..1a
AUe.f\8U..e 6
AI18.nall". .
AU..nal.... 2
Alte.natlv. J
AU..nal.... 4
AU..naU... S
0.... PmllIC1lUO of
PutIIIc He8lh and Ih8
Enwonmenl
No ~.prov1d8d
W. provide overa.
protection of IU*:
heaIh W. noI
inunedI8IeIv fII'*a lhe
-~ lrom .
011. SoW CIft)Uf1dIIIt....
oont8lllln8l1on
W. pruvwte overal
prot...,,,,,, of IU*:
healh. .. noI prua1
.he -1IOf1fn8f1I 'rom
.,..........
oonI_llOI1
CGmpNnm ...h
. ARAR'. 1St... and
f...eI Reyu&aIIonaI
0... noI CIDIItfJIr willi
.... ........
CompIi8a with ..
8IIIJIic88II8 .... ....
...... ........ lor
..... JIIQUfII»""
an"""'"
W. pnNlI1B ""&laY
prot""',on of puUoo;
healh ....11he
-- sp8I:''''''
by lhe 0 P lJrwfs
obfBd'ves
. Same 85 Alemalove 4
Sa,,,.. as AI"m8lhle 4
o
o
0'\
o
----__'__0______---..--- -..---- .
s ."... as AI_- 4
Doea noI ~ w8h
.... .... .....11
regulations 0IIn08fTW1U
gmundIIo- ...,...
lion.
#
Lang.- ~
.... ..........
0... noI .......
0IIIIIMI8I8I8d QIIQUfId
.....
Lang.18Im ~
of 01.", glUUflllw8181
.. -**'W oa:ur
- .. ....... of
~ II» 08.'"
"""'_1188 ......
....--...
~ ..-wIa IU*:
... of gIOUI1doI-
Doea noI ~
........ oontamine.
.ion
CDmploes ..Ih al
eppI8:.able slate -
IedoNIi ~ lor
IIIh... \IIOUf1dw-
ronIllllin8lion
Same as AIIen...",e 4
. - ------. --.--.-
. ---------'-----'-----'-- ------ -._-" ----- .--..-
W. I8fJIOV8 ronI8ffII'
nanls lrom 011-...
JIfOUfIdw-. but dues
noI 8dIhu anami.
nanI ....... 110m Ihe
... May cauu
~ c:h8ngea in
Ih8 WMI8ndI
Reduction of foaUly,
Ma8Ii8Iy. Of VoUne
Redua8 gmundIIo-
08.'" ID MCLI
Doea ... ...... 01
8IIIninIII8 .... hal81dDu8
.....
...... gro&RIw-
~ INving
.. ... ID UCla.
S_u~l.
W. f8f'ROV8 OOf1Iaml.
R8fIIs prioo 10 them
..-.ng 'he t:I88II. but
~ noI lWn8dI8Ie Iha
011.. gmundIIo-
May cNng8 -18nds
Remedl8loons oft. sae
\IfOUIIdIoraner -"'1Iv
r~~"ln9 (ont..l-
nants .nt~rln9
th~ (r~~'\.
--~-, ------------------..
S.'ne as AlemaalVe 4
I
L"
,~
I
Reduces oonIam",at"",
..-ing ... moeks
~ noI ......
grourdoo- m
-------
5 9
~ '\ ". 1
LJUo
-53-
~
-36Ci -
~
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vii)
viii)
7
~~U~
-54-
is estimated that these extraction wells will have a pumpinq rate of
approximately 30 qpm each. Approximate locations of these
extraction wells are shown in Figure 19; however, locations of these
wells could chanqe based on movement of the contaminant plume.
iii)
Groundwater from all extraction wells will be pumped via a forcemain
system to the treatment plant on the Site property as shown in
Fiqure 19. It is estimated that approximately 8000 to 9000 lineal
feet of forcemain will be required to connect all of the extraction
wells and the treatment plant.
iv)
Contaminated qroundwater will be treated in the treatment plant
usinq a system conceptually desiqned to consist of settlinq tanks
for solids removal, air strippinq and final carbon adsorption
treatment for off qas treatment and final qroundwater polishinq
prior to discharqe. A conceptual desiqn of the system is shown
schematically in Figure 20. It is estimated that the plant will be
treatinq approximately 550 qpm of water contaminated with an
approximate total Voc concentration of 15 mqlL. The treatment
system will be required to comply with air emissions standards and
NPDES requirements (see paqe 49) prior to surface water discharqe
and may be modified to meet these requirements.
V)
Treated water will be discharqed to one of the nearby surface wate~
bodi.s (Puqh or Clover creek) in compliance with NPDES requirements
via a forcemain pipinq system.
vi)
Groundwater monitorinq will be conducted to determine the
effectiveness of the qroundwater extraction and verify that
qroundwater remediation qoals (Table 12) are reached for the
off-site qroundwater beyond the POCo
Deed restrictions, siqns, and institutional controls will be
established to identify the presence, quantity and nature of wastes
in the disposal area and qroundwater and limit uses of both until
remediations are complete.
Haintain the qroundwater treatment system and the disposal area.'
cover. Maintenance of the disposal areas will include:
a)
periodic inspection of the disposal areas' surface includinq
slopes;
b)
periodic inspection of the monitorinq well network and property
fence;
C)
periodic mcwinq of the veqetation over the disposal areas'
cover;
d)
the application of fertilizer at a specified frequency;
e)
re-establishment of veqetation over distressed areas;
f)
periodic repair of areas eroded by surtace water runoff,
q)
maintenance of the property fence and signs; and
h)
control of burrowinq animals.
~
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J
9
-; ;-
G 0.j 3
(I
.-
..
~
51 't IQ.IHO AA.
~1I.;'0IW:t....... ntOW "'tAT'WOIT 8I\..NI' 'tI
".aCTION ...c....s IitOT ~ ~ Q.MIn
souacr' oj IOl'~6. [a,t )",.lO.".G..(
.[''''.(U(I:. .,';s
:! '[ "..wI ~1,o.O.""(j..(
'(....usn JS.iS
.
(..~&CTlQfio C4
.
;~ JH-SiTt/OJ"'-SlI't I1I(AT\IOIr~'
::3,-"RE : 9
AL tERN A TIVt: '-REMEDIAL COMPONENTS I
I
FJ'I~U. "0 "(At\I("r ~t
..
,
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,
"
EXTRACTION
SYSTE"
7~
~
<:::=::: GROUNDWATER
-.+.----.
EQUALIZATION
AND S£nuNG TANK
;t
~ ~ AIR INTAKE
o~
=>0
uti!:
~
SLUDGE HANDLING
SYSTEM
PUMP
BLOWER
0°0°0°
0°r800
o~ °
°0°0°0
°0°0°0
°0°0°0
°0°0°0
° ~o
OO~oO
OONdOO
oONloO
OO~~oO
o 0
00 000
000
--'
2 STAGE VAPOUR PIIASE
CARBOt4 ADSORPTION SYSTEM
,
MIST
EliMINA lOR
1_--.__....
... -- --....
,
9
-~IOVlNI
2 STAGE AQUEOUS
PHASE CAlmON
ADSORPTION
SYSTEM
DISCtfARGE
--- .-. ~
1'101](1-: ~o
PROPOSED GROUNDWATER TREATMENT SYSTLM
~
AIR STRIPPING
COlUMN
EfflUEN T
S lORAGE TANK
U1
'-0
C)
c-'
c,
~
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~
r
)
9
. '-, '." \
, I L ') :J
ix)
Identify and evaluate possible additional remedial actions requ~red
for addressing the contam~natlon of the ent:re S~te ~nclud~ng the
contaminant source (disposal areas) and possible environmental/
ecological concerns and prepare a feasib~lity study to discuss the
alternat~ves. possible treatao::ity stud:es and/or add:t:onal
sampling may be requ~red.
In additlon to the above activit:es, varlOUS support act:vities :ncluding the
implementat~on of a worker health & safety program and env:ronmental mon:torlng
for ind~cator chemlcal em~ss:ons will be conducted.
The estimated costs of alternatives 2 and 6 are shown in Tables 15
combined cost for this selected remedy, excluding the cost for the
identified in paragraph ix above, is estimated to be approximately
dollars.
and 16. The
work
11,644,000
Continqency Measures
The goal of this remedial action is to restore the groundwater to its
beneficial use, which is that of a drinking water source. Based on information
obtained during the remedial investigation and the analysis of all remedial
alternatives, EPA believes that the selected remedy may be able to ach:eve this
goal.
It may become apparent, during implementation or operation of the groundwater
extraction system and its modifications, that contaminant levels have ceased to
decline and are remaining constant at levels higher than the remediat~on goals
in Table 12 over some portion of the contaminated plume. In such a case, the
remediation goals and/or the remedy may be r~evaluated.
If the selected remedy cannot meet the specified remediation goals, at any or
all of the monitoring points during implen. tation, the contingency measures
and goals described in this section may rep~ace the selected remedy and goals
for these portions of the plume. such contingency measures will, at a minLmum,
prevent further migration of the plume and include a combination of conta:nment
technologies and institutional controls. These measures axe considered to be
protective of human health and the environment, and axe technically pract~cable
under the corresponding circumstances.
The selected remedy will include groundwater extraction for an estimated per~od
of 30 years, during wbicb time the system's performance will be carefully
monitored on a regular basis and adjusted as warranted by the performance data
collected during operation. MOdifications may include any or all of the
followingl
a)
at individual wells where cleanup goals have been attained, pump:ng
may be discontinued;
b)
alternating pumping at wells to eliminate stagnation points;
C)
pulse pumping to allow aquifer equilibration and encourage adsorbed
contaminants to partition into groundwater; and
d)
installation of additional extraction wells to facilitate or
accelerate cleanup of the contaminant plume.
,
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5
9
Q 0 ,S G
TABLE ~S
REMEDIAL COST ESTThiA TE. At TER.'iA TIVE A2.
HARDEMA.'l COlJ~ lA.'iDFILL SITE
     .4""1<411  Prts~t Worth  T.Jt4l1 Prutflt
1 ttm Ducri p ti Oft  C4Ip"t4l1 Costs  O&M Costs  of O&M Costs  Worth Costs
1. !I1stiN[ional Conrrols S 3.5,000 S 68 ,COO S 641.000 S 67"6.C(()
~ ~1aintain Existing Clay Cap    9 ,COO   as ,000  8= C(()
3. On-Site Hydraulic Containment  550,000  25 ,000  US,.500  ;- 55 ,.5.)J
4. Groundwater Treatment  1 ,J8S ,cro  325,000  3 ,064 ,cro   H49,ro::J
5. Discharge  200,000  10,COO  94,000  294.ro::J
6. !I1direct Capital Costs  976.300  °  °  9iL,,"'(J
 Subtotals S 3,146,500 5 ~37,COO 5 4,120,000  
 Total &timated Present Worth C08t . Altemative A2.     S 7,266,(0)
..
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-59-
5
9
,0067
TABLE 16
R£',.~ro[AL COST ESTIMATE. ALTERNATIVE ("
HARD£',.{A." COl::-.n L\:-.iDFILL SITE
     "'""11,,1  Pru"t Worth  Tot"l Prtsmt
ftrm Drscr;pho"  CiJp"t,,[ Costs  O&M Costs  of O&.~ Costs  Worth Costs
1. ::"cstit1Jtional Controls S 40 ,COO S l09,COO S 1.028,COO S 1.:60 ,COO
, Off-Site Hydraulic Removal  970,COO  40 ,COO  377.COO  U47.XO
3. Groundwater Tn!atment  2i5,COO  100 ,COO  94J,COO  1.2:8,COO
 (additiona! costs)        
.{. Discharge  50,000  10,000  94 ,COO  144.COO
5. lr1direct Capita! Costs  601 ,COO   0  0  60 1. COO 
 Subtotals S 1.9J6,COO S 259,COO S 2,-44:,COO  
 Totoll utimolt~d Pres~nt Worth Cost. Alt~matin"'"     S 40378,000
,
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5
9
,0068
-60-
To ensure that the remediation goals continue to be maintained, the aquifer
will be monitored at those wells where pumping has ceased on an occurrence of
every quarter for 5 years following di~continuation_of groundwater extraction.
If it is 'determined, on the basis of the preceding criteria and the system
performance data, 'that certain portions of the aquifer cannot be restored to
their benet'icial use, any or all of the following measures invclving long-term
management may occur, for an indefinite period of time, as a modification of
the existing system:
a)
engineering controls such as physical barriers, or long-term
gradient control provided by low level pumping, as containment
measures;
b)
chemical-specific ARARs will be waived for the cleanup of those
portions of the aquifer based on the technical impracticability of
achieving further contaminant reduction;
C)
institutional controls will be provided/maintained to restrict
access to those portions of the aquifer which remain above
remediation goals;
d),
continued monitoring of specified wells; and
e)
periodic reevaluation of remedial technologies for groundwater
restoration.
The decision to invoke any or all of these measures may be made during
periodic review of the remedial action, which will occur at leAst once
five (5) years. If any or all of these measures are determined to be
necessary, an Explaination of significant Differences ("ESD"), or a ROD
Ammendment will be issued to inform the public of these actions.
a
every
STATUTORY DETERMINATIONS
Under its legal authorities, EPA's primary responsibility at superfund sites is
to undertake remedial actions that achieve adequate protection of human health
and the environment. In addition, section 121 of CERCLA establishes several
other statutory requirements and preferences. These specify that when
complete, the selected remedial action for this site must comply with
applicable or relevant and appropriate environmental standards established
under Federal and State environmental laws unless a statutory waiver is
justified. The selected remedy also must be cost effective and utilize
permanent solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable. Finally, the statute
includes a preference for remedies that employ treatment that permanently and
significantly reduce the volume, toxicity, or mobility of hazardous wastes as
their principal element. The following sections discuss how the selected
reme~y meets these statutory requirements.
protection of Human Health and the Environment
Based on tbe site risk assessment, long term exposure to contaminants through
the consumption and use of contaminated groundwater is the identified risk
associated with the Site. Althougb no excessive risk was identified for
exposure to the wastes contained in the disposal areas, th~s risk level was
~
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5
9
0069
-~~-
based on present conditions which include a temporary cover over the disposal
areas.
The selected remedy protects human health and the environment through
extract~on and treatment of the contaminated groundwater. The contaminants
will be permanently removed from the groundwater by air str~pp~ng. The
volatile d~ssolved gases w~ll be transferred to the air stream for treatment by
carbon adsorpt~on and release to the atmosphere in compliance with Clean A~r
Act regulations.
Extraction of the contaminated groundwater also will eventually eliminate the
threat of exposure to the most mobile contaminants from direct contact or from
ingestion of contaminated groundwater. The future carcinogenic r~sks
associated with these exposure pathways are as high as a one in one for
consumption of the contaminated groundwater. By extracting the contam~nated
groundwater and treating, the cancer risk in the consumption of off-site
groundwater will be reduced to about 8.2 X 10-5 and an Hazard Indices (HI)
ratio of less than 1. These levels are within the range of acceptable exposure
levels of between 10-4 and 10-6 and an HI ratio of less than 1. There are
no short-term threats associated with the selected remedy that cannot be
readily controlled. In addition, no adverse cros.-media impacts are expected
from the remedy.
The contingency r~medy, if required, will provide overall protection of
health and the environment through a combination of ma.. reduction and
institutional and/or engineering control..
human
Compliance with ARARs
The selected remedy of hydraulic containment and treatment
groundwater at the PCC and extraction and treatment of the
beyond the PCC will comply with all Applicable or Relevant
Requirements (ARAR8) or the contingency remedy will attain
waiver of any ARARs. The ARARs are pre.ented below:
of the on-site
off-site groundwater
and Appropriate
or justify the
Action specific ARARs:
*
clean Water Act (40 CFR Part 122)
*
Tenne..ee water Quality Control Act, TN code 69-3-104
*
clean Air Act (40 CFR Parts 50-62)
Chemical Specific ARARs:
*
Safe Drinking Water Act (40 CFR Part. 141, and 143)
*
Tenne..ee Water Quality criteria (1200-4)
Location specific ARARs
*
Response in a Floodplan or wetlands (40 CFR Part 6, Append~x A)
*
RCRA (40 CFR Section 264.95)
*
clean Water Act (section 404) (40 CFR Part 230) (33 CFR Parts
320-330)
,
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-62-
5
9
0070
RCRA LDRs are not generally applicable to the groundwater extraction and
treatment process; however, should levels in the waste residuals in the sludge
from the treatment process exceed allowable standards, the sludge will be
disposed of in accordance with LDRs.
Cost Effectiveness
The selected remedies are cost-effective because they have been determined to
provide overall effectiveness proportional to their costs. Alternatives 2 and
6 have an estimated net present worth value of $11,644,000. Alternative 6 is
the least costly and the mostly easily implemented of Alternatives 4,5 and 6
which meet all off-site ARARs.
Utilization of Permanent solutions and Alternative Treatment Technoloqies (or
Resource Recoverv Technoloqies) to the Maximum Extent practicable
The State of Tennessee and EPA have determined that the selected remedy
represents the maximum extent to which permanent solutions and treatment
technologies can be utilized in a cost-effective manner for op Unit i1. of
those alternatives that are protective of human health and the environment and
comply with ARARs, the state of Tennessee and EPA have determined that this
selected remedy provides the best balance of tradeoffs in terms of long-term .
effectiveness and permanence, reduction in toxicity, mobility, or volume
achieved through treatment, short-term effectiveness, implementability, cost,
also considering the statutory preference for treatment as a principal element
and considering state and community input.
The selected remedy reduces the toxicity, mobility, and volume of the
contaminants in the groundwater: complies with ARARs; provides short-term
effectiveness; and protects human health and the environment. The selected
remedy will be easier to implement technically because it requires less
construction and is less likely to destroy the wetlands around clover creek.
Finally, the off-site portion of the remedy costs the least of the equally
protective off-site alternatives. The major tradeoffs that provide the basis
for this selection decision are long-term effectiveness, implementability, and
cost. .
The selected remedy is more reliable and can be implemented more quickly, with
less difficulty and at less cost that the other treatment alternatives and is
therefore determined to be the most appropriate solution for the contaminated
groundwater caused by the release of hazardous substances from or at the site.
Preference for Treatment as a principal Element
By treating the contaminated groundwater in an on-site treatment plant
consisting of an air stripper and carbon adsorption then discharging the
treated effluent to one of the nearby surface water bodies, the selected remedy
addresses the principal threat of future direct contact/ingestion of
contaminated groundwater posed by the site through the use of treatment
technologies. Therefore, the statutory preference for remedies that employ
treatment as a principal element is satisfied.
~
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