United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R05-89/101
September 1989
SEPA
Superfund
Record of Decision
Big D Campground, OH
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50272-101
REPORT DOCUMENTATION
PAGE
1. REPORT NO.
EPA/ROD/R05-89/101
3. Recipient1* Acce**lon No.
4. Title and Subttt*
SUPERFUND RECORD OF DECISION
Big D Campground, OH
First Remedial Action - Final
s. report Dat»
09/29/89
7. Author(«)
8. Performing Organization Rept Mo.
9. Performing Organization Nun* and Addras*
ia Pro(KtfTMlUWork Unit No.
11. Contract(C) or Cr*m(G) No.
(C)
(Q)
12. Sponsoring Organization Nnm and Addm*
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report a Period Covered
800/000 ~
14.
15. Supplementary Note*
16. Abstract (Umit: 200 word*)
The Big D Campground site is in Kingsyille, Ashtabla County, Ohio. The site consists of
a 1.2-acre landfill created out of a former sand and gravel quarry. From 1964 to 1976
the site owner accepted approximately 28,000 cubic yards of hazardous materials for
disposal which included up to 5,000 drums containing solvents, caustics, and oily
substances. A 1986 remedial investigation identified the landfill as the primary source
of contamination in soil outside the landfill and ground water underlying the landfill.
Ground water contamination is of significant concern because it is migrating towards the
drinking water supply wells of nearby residences and Conneaut Creek which is adjacent to
and south of the site. The primary contaminants of concern affecting the soil and ground
water are VOCs including PCE and TCE, other organics, and metals including chromium and
lead.
The selected remedial action for this site includes removing and incinerating up to
5,000 buried drums, bulk wastes, and up to 30,000 cubic yards of contaminated soil
followed by onsite disposal of nonhazardous ash residue; pumping and treatment of
40,000,000 to 60,000,000 gallons of ground water using an onsite granular activated
carbon system followed by onsite discharge to Conneaut Creek; arid ground water and
surface water monitoring. The estimated present worth cost for this remedial action is
$39,000,000, which includes annual O&M costs of $320,000.
OH
17. Document Analysis a. Descriptor*
Record of Decision - Big D Campground,
First Remedial Action - Fina7!
Contaminated Media: soil, gw
Key Contaminants: VOCs (PCE, TCE), other organics, metals
b. Identifiers/Open-Ended Term*
(chromium)
c. COSAT1 Held/Group
18. Availability Statement
19. Security a*** (Thi* Report)
None
20. Security Ctcu (Thi* Page)
None
21. No. of P*ge*
119
22. Price
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Record of Decision
DECLARATION
SITE NAME AND
Big D Campground
Kingsville, Ohio
OF BAJTS JP
This decision document presents the selected remedial action for the Big D
Campground site in Kingsville, Ohio, developed in accorttanoe with CERCIA, as
amended by SARA, and, to the extent practicable, the National Contingency Plan.
This decision is based on the administrative record for this site. The
attached index identifies the items that comprise the administrative record
upon which the selection of the remedial action is based.
The State of Ohio has concurred on the selected remedy.
QF Sl'JL'Jb!
The site consists of a drum and bulk waste fHcfocai area created in a former
sand and gravel quarry. Up to 5,000 drums and 30,000 cubic yards of bulk
wastes are believed to be buried at the site. Ground water in contact with
these wastes is migrating towards nearby residences to the north and into the
Conneaut Creek adjacent to and south of the site. Actual or threatened
releases of M7arrt'""g substances from this site, if not addressed by
implementing the response action selected in this Record of Decision (ROD) , may
present an imminent and substantial endangerment to public health, welfare, or
the environment.
OF THE
The selected remedy »f**re^ss** all risks posed by contamination in the source
area (landfill) and ground water. The source area will be excavated and
incinerated and the ground water will be collected and treated.
The major components of the remedy include:
Deed restriction
Site fencing
Source area excavation
Incineration on-site
Disposal of treated material and backfilling on site
Ground water collection
Ground water treatment on-site
Discharge of treated ground water to Conneaut Creek
Ground water and surface water monitoring
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DECLARATTCN
The selected remedy is protective of human health and the environment, a waiver
can be justified for whatever Federal and state applicable or relevant and
late requirement that will not be net, and is cost effective. This
remedy satisfies the statutory preference for remedies that employ treatment,
reduces toxicity, mobility, or volume as a principal element and utilizes
permanent solutions and alternative treatment technologies to the maximum
extent practicable* Because this remedy will result in Hay-arAnug substances
remaining en-site, the five-year facility review will apply to this action.
Valdas V.
Regional Administrator
U.S. EPA, Region V
J0-
Date
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ROD DEdSICN SCMftRY
I. Site -Name, Location and Description
The Big D Campground ("Big D") site is located in Kingsville, Ashtabula County,
Chio, approximately 2.5 miles south of Lake Erie and 50 miles northeast of
Cleveland. The site is located south of Creek Road, north of Conneaut creek
and west of, and adjacent to, "Big D Kampground" (see Figure 1).
The landfill at the site is approximately 1.2 acres in size and approximately
20 feet deep. The I****f11i is located on a relatively level surface which
gently slopes north towards Lake Erie. Approximately 50 feet south of the
southern edge of the landfill the land slopes sharply towards Conneaut Creek
(approximate 32% slope).
The site is bordered by Conneaut Creek to the south, a campground to the
southeast, open land to the west, residences with small acreage to the north
and northwest, and a swamp area approximately 1/2 mile to the north. The
residences are .located approximately 500 feet north of the site.
Residences within 1/2 mile of the site, north of Conneaut Creek, use ground
water for drinking.
II. Site History and Enforcement Activities
The Big D Campground site was initially operated as a sand and gravel quarry
which was subsequently filled with hazardous and non-hazardous materials. The
active ^«=rv>eai period lasted from 1964-1976. ' •
Most of the materials placed in the landfill were drummed, but some bulk
toluene diisocyanate (TDI) was also rfigpnegH- it is estimated that 2500 to
5000 drrmg are buried at the site. Ine drummed t^ay-arrimia materials include
non-halogenated and halogenated solvents, caustics and oily substances. Other
wastes believed to have been disposed of at the site include: spent vacuum
pump oil, TDI residue contaminated with mcnochlorobenzene (MCB) and carbon
tetrachloride, earth contaminated with diaminotoluene (TDA) and TDI, flyash,
trash, monoethanolamine (MEA), off-specification TDI, and TDA and TDI in sample
cans and bottles. The vacuum pump oil may have been contaminated with TDI, MCB
and trace levels of phosgene. The total volume of hazardous substances
disposed of at the site is approximately 28,000 cubic yards.
Preliminary investigations began at the site in 1982. As early as 1982, the
major PRP at the site was sent information on these investigations. In
December, 1982 the site was proposed for the National Priorities Lost (NPL) of
Superfund sites. On September 8, 1983, the site became final on the NPL.
Olin Chemicals Corporation, a major PRP at the site, made comments on this
proposed listing in February of 1983. In April 1985, notice letters were sent
to three PRPs; Olin Chemicals Corporation (generator), Brenkus Construction
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Co. (operator), and Mr. Dreslinski (current site owner). Olin was sent a
CERCIA Section 104 (e) information request at approximately the *«*»*» time, to
which they responded in July 1985.
Olin's response indicated that they were a substantial contributor of
substances to the Site and would be the focus of RI/FS negotiations.
In November 1985, a reminder that notice had been provided and a draft scope of
work for the RI/FS was sent to the potentially responsible parties (ISPs) . In
fr 1985, negotiations to conduct the RI/FS began with Olin, the only PRP
to respond positively to EPA's request. In early January 1986, technical
questions arose and EPA reiterated that a consent order would need to be agreed
upon by February 15, 1986 for Olin to conduct the RI/FS. No agreement was
reached and EPA terminated the RI/FS negotiation period shortly after
February 15, 1986.
Olin fymt-tptMd to be interested in the remediation process and sent letters
protesting the termination of the negotiations. Among these was a counter-
proposal to do the RI/FS delivered to the Regional Administrator.
The fund-financed RI began in late 1986 and was completed in mid-1988. The
final RI, FS and Proposed Plan were released for public comment on July 28,
1989. A public meeting to (tismss these documents was held on August 8, 1989.
The public comment period ended on August 26, 1989.
Special Notice for RD/RA negotiations win be isrevyl to PRPs before
September 30, 1989.
III. Community Relations History
On August 14-15, 1986 Community Relations personnel from the U.S. EPA and ICF
Technologies, Inc. travelled to Cleveland, Ohio and drove to the towns of
Mentor, Jefferson and Kingsville, Ohio, where they met with and interviewed
County and Township officials and residents.
A Fact Sheet was distributed to the public in December, 1986 which HiOTvagorf
the RI scheduled to begin that month. A RI kickoff public meeting was held on
February 5, 1987.
On July 28, 1989 the Final RI report, FS report and Proposed Plan were
released to the public for eminent. The PRPs were sent a copy of the FS and
Proposed Plan on July 27, 1989. A public moot ing was held on August 8, 1989,
in Kingsville, Ohio, to «Mgr"gg the RI, FS and Proposed Plan, and to receive
official comments on the Proposed Plan. The public comment period ended August
26, 1989. Comments received and responses to comments are aiVirPs.qpri in the
Responsiveness Summary.
IV. Scope and Role of Response Action
The remedial action will arttppss the principal threats at the site; ground
water contamination and the source area (landfill) contamination. The RI
identified total cancer risks as high as 1 x 10~2 under worst case conditions
for ingestion of groundwater. Non-carcinogenic risks were also identified for
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ingestion of groundwater, based on worst case conditions.
Die major source of contamination identified at the site is the landfill.
Therefore the alternative chosen to remediate contamination at the site will
address contamination in the ground water and source area. The site risk
objectives will reduce health risks in the groundwater and the soils adjacent
to the source area (which may pose a risk based en ingestion or direct contact)
to a cumulative Hazard Index of 1.0 or less and a cumulative carcinogenic risk
of 10"6 or less.
V. Summary of Site Characteristics
The RI investigated the contaminant source area (landfill) , soils outside the
source area, groundwater and surface water and sediment. Table 1 summarizes
the maxjjmjm concentrations of indicator chemicals (see V. B. Fate and
Transport, page 5) identified in different mfriia at the site.
A. Nature and Extent of Contamination
A geophysical survey was performed which indicated a rectangular trench in the
northern area of the site (approximate size 1.2 acres) . Based en the
geophysical survey two test pits were excavated. These pits verified the
presence of buried drums (intact and either partially crushed or ruptured) ,
bulk waste and contaminated soil in the source area. Analytical results
revealed that the same organic compounds found in the ground water and
subsurface soil samples are also present in the source area/ but at greater
ounce! iti'ations .
(ou*"'ai
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alluvial aquifer and the bedrock aquifer (see Figure 2) .
At the upper portion of the site the water table aquifer is hydraulically
separated from the bedrock aquifer. At the lower portion of the site the
alluvial ««ji< far and the semi-confined *«j *i for" are HyrtraiiUffaiiy connected.
Ground water in the water table aquifer at the upper portion of the site flows
both north and south. The approximate location of the ground water divide
occurs at the southern edge of the landfill. Ground water flows north towards
local discharge points and flows south toward Ccnneaut Creek. The confined
bedrock aquifer locally flows south to Ccnneaut Creek.
Two rounds of ground water sanpling were nmrhrtad at wells around the source
area, wells located south of the source area near the creek and six off-site
residential wells. Shallow wells on-site and near the creek showed
concentrations of inorganic contaminants above background levels. Deep on-
site wells also have concentrations of some inorganic constituents above
background levels.
Organic indicator compounds were detected in shallow on-site wells and wells
near the creek. The indicator chemicals (see V. B. Fate and Transport, p. 5)
detected include cnlorobenzene, 1,2- and 1,4-dichlorobenzene, trans-1,2-
dichlorobenzene, diaminotoluene, tetrachloroethene, trichloroethene and vinyl
chloride. Deep wells on-site detected organic compounds at low concentrations.
This indicates the possibility of vertical contaminant migration through the
aquitard at localized areas.
Qxnpounds found in creek wells (lower portion of the site) were the same as
those found in shallow wells (upper portion of the site) however the
concentrations in the creek wells were considerably less.
One of the six residential wells sampled showed concentrations of inorganic
contaminants similar to wells on site. This residential well is not used by
the owner but was sampled due to its proximity to the site. The source of the
inorganic contamination is probably the site. However, the aquifer from which
the residential well is drawing water appears to be above and separate from the
water table aquifer in which on-site monitoring wells are located. Past
fluctuations in the ground water levels of the water table aquifer could have
caused inorganic contamination to migrate into the perched aquifer.
Organic compounds were detected in one of six residential wells (the
Dreslinski campground well) . This well had been chlorinated with Chlorox
Bleach shortly before the sampling occurred. This chlorination is probably
the source of chloroform (12 ug/1) , bromo-dichlorcmethane (2 ug/1) and
dibromcchloromethane (2 ug/1) identified in the sample from that well.
Surface Water and Sediment
Inorganic contamination in the surface water was detected in Conneaut Creek.
However, the concentrations of manganese, magnesium, sodium and calcium were
only slightly elevated above background levels.
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Organic analytical results indicate the presence of chlorobenzene in Conneaut
Creek. The concentrations are much lower than those detected in the ground
water and lower than applicable regulatory standards.
Inorganic and organic contaminants were identified in the sediment near the
site. Ihe concentrations noted were only slightly above background levels.
B. Fate and TranspozL
Thirteen of the twenty-five contaminants identified in the source area, soils,
ground water and surface water were identified as indicator chemicals.
Indicator chemicals were chosen based on factors such as the number of tirras a
chemical was detected, the ™aytmim concentration, and persistence and toxicity
to human health and the environment. Hie indicator chemicals at Big D
Campground are listed below:
Inorganics Organics
barium chlorobenzene
beryllium 1,2-dichlorobenzene
chromium 1,4-dichlorobenzene
lead trans-l,2-dichloroethene
nickel diaminotoluene
trichloroethene
tetrachloroethene
vinyl chloride
Inorganic Contaminants
Inorganic contaminants are present in the source area, surface soils,
subsurface soils and ground water. Inorganics in the soils can (1) migrate to
Conneaut Creek by runoff from surface soils and move with the Creek,
eventually collecting as stream sediment, (2) migrate up from the saturated
zone into the unsaturated zone due to fluctuating ground water levels, (3)
remain attached to unsaturated subsurface soils, or (4) move with ground water
from the source area and subsurface soils.
Inorganics in ground water in the water table aquifer are not expected to
migrate to a significant degree, however, part of the source area is in the
ground water. Ground water coming in contact with the source area can have
contaminant concentrations as high as the solubility limit for specific
Inorganics present in the alluvial and bedrock aquifers may (1) attach to
subsurface soils and not migrate, or (2) discharge to Conneaut Creek and
in concentration due to dilution or attaching to creek sediments.
Organic Contaminants
Organics were detected in the source area, surface soils, subsurface soils and
ground water. Organics in the source area and soils can (1) migrate to
Conneaut Creek by runoff from surface soils and volatilize or accumulate in
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stream sediments, and (2) migrate from the source area and soils into ground
water by moving vertically via precipitation or fluctuating ground water
levels (the bottom of the source area is located in ground water).
The major pathway for organic contaminant movement at the site is by ground
water flow. Qrganics will generally move with the bulk ground water flow and
the attachment to soils will be minimal because less than 10 percent silt and
clay is present in the sandy water table aquifer; sands do not typically adsorb
organics. Qrganics in the ground water can also diffuse upward from the ground
water into the unsaturated zone soils or atmosphere.
Qrganics in the ground water can discharge into Oonneaut Creek where the
oonwiftTdfr JTE? of organics will A»r»rp^jao due to dilution, attaching to
sediments, sedimentation and aquatic uptake (ingesticn). In addition, organic
contaminants in the surface water may decrease due to volatilization.
VI. Summary of Site Risks
A. Summary of Exposure Assessment
Six site-specific exposure scenarios were identified:
-Ingesticn of contaminated soil
-Direct contact with contaminated soil
-Ingesticn of contaminated ground water
-Incidental ingesticn of contaminated surface water
-Direct contact with contaminated surface water
-Ingesticn of contaminated aquatic life
An exposure scenario based on contaminants in the source area was not
evaluated. r.-iTni-t-oH sampling was conducted in the test pits excavated in the
•source area. The sampling in the source area was conducted only to get
general information on the material in the landfill and to confirm that
contaminants identified in the ground water and soils originated in the
landfill. Any carcinogenic or non-carcinogenic risks identified through other
exposure scenarios also apply to the source area. However the risks in the
source area would be greater because the concentration of contaminants in the
source area are greater.
Table 2 summarizes the six exposure scenarios identified and the populations
with each.
B. Toxicity Assessment
This section summarizes significant adverse health effects to humans and the
environment posed by the indicator chemicals at the Big D site.
Barium is well absorbed but less toxic than most other metals. Acute doses
interfere with the function of all muscle tissue, producing a wide variety of
effects. Chronic toxicity, except for lung lesions after inhalation and
aquatic toxicity, are not well defined.
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Beryllium is very poorly absorbed. It produces irritation at the contact
point. Like barium, chronic tcxicity, except for lung lesions after
inhalation and aquatic toxicity, are poorly defined.
Most chromium toxicity is due to hexavalent chromium. Ihe main effect of
overdoses is irritation at the point of contact. Chronic inhalation of
hexavalent chromium produces lung tumors. Other target organs are the kidney,
blood forming tissues and liver. Chromium is also toxic to aquatic species.
Lead is fairly veil absorbed and accumulates in the skeleton. The main toxic
effects are on the nervous system. Lead poisoning in children can inhibit
growth and produce permanent learning defects. Lead is toxic to fish, however
toxicity decreases as water hardness increases.
Nickel is a poorly absorbed metal. The major toxic effects are irritation on
contact and allergic sensitization. Inhalation causes respiratory tract
tumors.
Chlorobenzene is absorbed after ingestion, absorbed from the lungs and not
absorbed through the skin. Acute doses produce irritation and central nervous
system depression. Repeated doses cause liver and kidney lesions.
Chlorobenzene is moderately toxic to aquatic species.
1,2-dichlorobenzene and its isomer, 1,4-dichlorobenzene, are very similar in
their biological effects, however the 1,2-isomer is usually more potent.
Dichlorobenzene is well absorbed by all routes. Acute doses cause irritation,
some central nervous system depression, blood toxicity and kidney lesions, but
the main effect is liver toxicity. Chronic doses produce similar effects.
Dichlorobenzene are more toxic to aquatic species than is Chlorobenzene.
Few studies have been performed with trans-l,2-dichloroethene. Its main acute
toxic effect is central nervous system depression. Repeated doses affect the
liver with sane lesser effects on other organs.
Trichloroethene is well absorbed after inhalation and ingestion but poorly
absorbed through the skin. Acute doses produce central nervous system
depression. Repeated doses produce liver, kidney and peripheral nervous
system lesions as well as tumors. Trichloroethene is toxic to aquatic species
but much less toxic than the metals of concern.
Tetrachloroethene is similar to trichloroethene but less potent as a central
nervous system depressant. It produces liver and lung lesions and tumors in
animals. Its toxicity to aquatic species is similar to that of
trichloroethene.
Vinyl chloride is carcinogenic to humans and animals.- Gaseous vinyl chloride
is rapidly absorbed in the lungs and aqueous vinyl chloride is well absorbed
from the gastrointestinal tract. Acute exposure produces central nervous
system depression. Repeated exposure produces hepatoxicity. A few large doses
or several small doses will produce a variety of effects in humans. In animal
studies, vinyl chloride produced some fetotoxicity at very large doses but no
teratogenesis. It is mutagenic in a number of in vitro and in vivo systems.
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8
Diaminotoluene is well absorbed orally but less so dermally. Acute doses are
irritating and discolor skin and hair. Diaminotoluene is a very potent
sensitizer and produces blood and liver lesions. Chronic doses prodigy liver
and other rumors.
C, Risk Characteristics
Using information presented in the previous sections, the actual or potential
risks to human health or the environment, associated with contaminants at or
released from the site, were assessed. The potential risks associated with
each exposure scenario are flinnififfifrl. Risk levels were calculated by using
estimated exposure doses and risk factors established by U.S. EPA.
To determine the non-carcinogenic risks, a hazard index (HI) was calculated for
each contaminant of concern for which an allowable chronic intake (AIC) has
been established by the U.S. EPA. The HI is the ratio between the estimated
exposure dose for each contaminant and the acceptable exposure level for that
same contaminant. In all cases, the AIC was used to represent each
contaminant's acceptable exposure.
Carcinogenic risks were evaluated in terms of upperbcund excess lifetime cancer
risks to children who ingest site soils from the upper or lower portions of the
site under probable case and worst case conditions. These risks were
calculated using the following equation:
Upperbcund Excess
Lifetime. Cancer Risk • (Average Lifetime Dose) x (Carcinogenic Potency Factor)
Recent U.S. EPA guidance indicates that the target carcinogenic risks
resulting from exposures at a Superfund site may range from between 10~4 to
10~7. U.S. EPA Region V has a risk policy that cancer risks of 10"6 or greater
are generally considered unacceptable. Thus, remedial alternatives being
considered should be able to reduce total potential carcinogenic risks to
levels of ID"6 or less.
Table 3 presents a summary of the potential risks associated with the various
scenarios evaluated. Potentially significant risks are defined as those with a
Hazard Index of 1.0 or greater or a cancer risk of 10"6 or greater.
Risk characterization of ingestion of, and direct contact with, contaminated
soils outside the source area did not identify any non-carcinogenic or total
cancer risks (see Table 3).
Ingestion of ground water identified total cancer risks as high as IxlO"2
under worst case conditions from all three aquifers. The contaminants
associated with these risks are 2,4-diaminotoluene, tetrachloroethene,
trichloroethene and vinyl chloride. Trichloroethene contamination levels
identified in ground water were up to 1500 times in excess of federal standards
for drinking water. Non-carcinogenic risks, based on worst case exposure
doses, were also identified for all three aquifers. The primary contaminants
associated with these risks are chlorobenzene and tetrachloroethene.
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Chlorobenzene oontami nation levels identified in ground water were up to 750
times in excess of federal standards for drinking water.
Risks associated with incidental ingestion of contaminated surface water,
direct contact with contaminated surface water and ingestion of contaminated
aquatic life were not evaluated. Minimal contamination was found in the
surface water and the contamination detected which exraaxk-rt federal
regulations (lead and beryllium) was only found in one downstream sample.
Also, contamination detected in the surface water was only slightly above
background values.
The potential risks to the environment were evaluated by focusing on the
aquatic life in Conneaut Creek next to and downstream of the site. Data on
bottom-dwelling populations collected from Oonneaut Creek indicated that the
biological community downstream of the site may be slightly impaired, however
further extensive studies of the data would be required to confirm this. The
water quality data were compared to the U.S. EPA's Ambient Water Quality
. Criteria and no significant impacts were detected. Therefore, releases of
contamination from the site may be only slightly impacting Conneaut Creek at
this time.
The proposed alterative to remediate contamination at the site will address
contamination in the ground water and the source area. The site risk
objectives will reduce health risks in the ground water and soils adjacent to
the source area (which may pose a risk based on ingestion or direct contact) to
a cumulative Hazard Index of 1.0 or less and a cumulative carcinogenic risk of
KT6 or less.
VII. Documentation of Significant Changes.
The selected remedy and the preferred alternative presented in the Proposed
Plan is alternative number 9 - On-Site Incineration, Ground Water Treatment.
There are no significant changes.
viii. Description of Alternatives
Nine alternatives were evaluated in detail in the Feasibility Study.
Alternatives numbers 2 through 5 were not in full compliance with ARARs '
because ground water treatment was not included. The FS details all nine
alternatives. Alternative 1, the no-action alternative, was also not in
compliance with ARARs, however it is being retained as a baseline for
comparison to other alternatives. Therefore Alternative number 1 and numbers 6
through 9 are summarized below.
A. Alternative 1 - No Action
1. Treatment Components
No treatment will occur.
2. Containment Components
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10
Wastes will not be contained.
3. Institutional Controls
Institutional controls will not be implemented.
4. ggtHiiBit'.ari Time for dplementaticn.
None
5. Estimated Capital, O&M, and Present Worth Costs
All costs are $0.
6. ARARs
This alternative does not comply with ARARs.
B. Alf^Tnative 6 ~ Sq^TrT!? Area Oon^inrDTTt. Treatment of Ground
the OontTaJTvyj Area.
1. Treatment Components
This alternative would collect ground water in the water table aquifer
with two interceptor trenches. Ground water in the alluvial, semi-
confined bedrock and confined bedrock aquifers would be collected with
extraction wells. The ground water will be treated on-site in a granular
activated carbon (GAC) system. However, should pilot testing during the
design phase indicate that pretreatment, such as sand filtration,
ozonation or air stripping, is needed to achieve necessary removal
efficiencies of certain compounds, the system will be adjusted
accordingly. The «a«^jjnqt*>H volume of contaminated ground water is 40 to
70 million gallons.
After treatment the effluent will be discharged to Conneaut Creek.
The cleanup levels to meet risk objectives for ground water are based on
future use scenario. The ground water treatment will reduce risks posed
from ingesting ground water to a cumulative Hazard Index of 1.0 or less
and a cumulative cancer risk of 10"6 or less.
Interceptor trenches, extraction wells and GAC treatment are easily
implemented.
2. Containment Components
This alternative would contain the buried drums, bulk wastes and
contaminated soils by placing a multilayer cap over the source area. The
cap would reduce infiltration and contaminant migration to the ground
water. The cap would cover approximately a 3-acre area (120,000 square
feet) and would be a soil-synthetic membrane cap.
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11
This alternative would contain the source area by surrounding the buried
drums, bulk wastes and contaminated soils with a slurry wall to prevent
horizontal migration of contamination. The slurry wall would be installed
.three feet into the hard grey clay unit underlying the water table aquifer
and the source area. The slurry wall would be approximately 25 feet deep,
3 feet thick and 1,100 feet long.
The wastes in the source area consist of buried drums (approximately
2,500 to 5,000 drums) bulk wastes and contaminated soils (approximately
25,000 to 30,000 cubic yards) contained in an area approximately 1.2 acres
on the surface and 20 feet deep. Risks posed by materials in the landfill
were not calculated because a representative sample was not able to be
obtained. Limits sampling identified that contamination in the landfill
was the same as that identified in other **><*]* except at greater
sentrations (See Table 1).
3. Institutional Controls
A fence will be installed around the perimeter of the capped area to
limit jy*~iogg to the site.
Pood restrictions would be. placed on the land which would be capped to
prevent future excavation or construction activities. Pood restrictions
would be placed on property overlying the contaminant plume and source
area to prohibit installation or use of drinking water wells in the three
aquifers identified at the site.
Long-term operation and maintenance would exist to maintain the cap.
Annual cap inspections and vegetation mowing will reduce the likelihood of
cap failure. Long term cap maintenance would be required to correct
settlement, erosion and other problems. The cap may need to be replaced
after 30 years to prevent infiltration and contaminant migration.
risk would remain from the drums, bulk wastes and contaminated
soils in the source area since they will not be removed or treated. long
term ground water monitoring in the water table aquifer will be necessary
to identify if the slurry wall fails. The expected life of a slurry wall
is 30 years.
4. Estimated Time for Implementation
The slurry wall and cap construction should take 1 to 1.5 years, which
includes testing, design, bidding, and construction. The ground water
collection and treatment system will take 6 to 12 months, which includes
testing, design, bidding, and construction. The total estimated time for
completion is 1.5 to 2.5 years. A ground water collection time of 20 to
60 years would be required to reach risk objectives for ground water in
all three aquifers. This estimate is based upon the amount of time
necessary to remove contaminants from the saturated portion of the
aquifer immediately below the source area and all contamination which has
already migrated from the source area.
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12
5. Costs
Estimated capital costs: $5,000,000
Estimated present worth: $8,000,000
Estimated annual O&M costs: $ 360,000
6. ARARS
Ground water treatment oust comply with chemical specific ARARs for
barium (MCL - 1,000 ug/L), chromium (MCL * 50 ug/L), 1,4-dichlorobenzene
(MCL » 75 ug/L), trichloroethene (MCL - 5 ug/L), and vinyl chloride (MCL
2 ug/L).
Action specific ARARs are listed on Table 4.
C. Alternative 7 - On-Site Incineration. Vitrification. Ground Water
1. Treatment Components
This alternative would remove buried drums from the source area
(approximately 2,500 to 5,000 drums) and incinerate the drums an-site.
Contaminated soils will remain in the source area. Ash remaining after
incineration, approximately 500 cubic yards, will be placed back in the
source area. The ash and soils will be stabilized by in-situ
vitrification. A soil contamination study will be conducted prior to
vitrification to identify the extent of contamination. An estimated
25,000 to 30,000 cubic yards of soil and ash will need to be vitrified.
After vitrification, the area would be backfilled to original grade with
clean native soil.
Ground water in the water table aquifer would be collected with two
interceptor trenches. Ground water in the alluvial, semi-confined
bedrock and confined bedrock aquifers will be collected with extraction
wells. The collected ground water will be treated an-site in a granular
activated carbon system. If necessary, additional pretreatment of ground
water will be implemented, see alternative 6. The estimated volume of
contaminated ground water is 40 to 70 million gallons.
After treatment the effluent will be.discharged to Conneaut Creek
The cleanup levels to meet risk objectives for the ground water are based
on a future use scenario. The ground water treatment will reduce risks
posed from ingesting ground water to a cumulative Hazard Index of 1.0 or
less and a cumulative cancer risk of 10"6 or less.
Vitrification technology is still developmental and very few contractors
are available to implement the technology.
Incineration, interceptor trenches, extraction wells and GAC treatment are
easily implemented.
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13
2. Containment Components.
This alternative does not include any containment components.
3. Institutional Controls.
The site will be fenced to limit access and to contain the source area
(excavation area), drum staging area, en-site incinerator, and the ground
water treatment system.
Deed restrictions will be placed on property overlying the source area and
contaminant plume to prohibit installation or use of drinking water wells
in the three aquifers identified at the site.
After incineration of drums and vitrification of soils, no long term
monitoring or O&M would be required at the source area.
Once ground water risk objectives are met long term monitoring will not be
necessary because the source area is stabilized.
4. Estimated Time for Implementation.
Drum removal, incineration and vitrification are expected to take 2 to 2.5
years which includes design, bid, mobilization, test burn, vitrification,
demobilization, and backfill activities.
The preparation activities for ground water collection, treatment, and
discharge would take 1.5 to 2.5 years for testing, design, bidding, and
construction activities and would be concurrent with the source area
rmmari \ at- |rm. 20 to 60 years is the g>g*-iTr'a'fr«»ri fc.in*» to collect and treat
all ground water to meet risk objectives (see alternative 6).
5. Costs
Estimated capital costs $36,000,000
Estimated present worth: $39,000,000
Estimated annual O&M costs: $ 350,000
6. ARARs
Chemical specific ARARs are the same as those for alternative 6.
Action specific ARARs are listed in Table 4.
D. Alternative 8 — Off—Site IncirvaT'ation. Ground Wafrpy Treatment
1. Treatment Components
This alternative would remove buried drums (approximately 2,500 to 5,000
drums), bulk wastes and contaminated soils (approximately 25,000 to 30,000
cubic yards) from the source area. The removed materials will be
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14
transported off-site to a RCRA permitted oiiiiiHunal incinerator. Drums,
bulk wastes and contaminated soils will be removed until the bottom of the
landfill or the water table is encountered. However, if drums or bulk
wastes are located within the saturated zone, they will be removed. The
water table is located approximately 17 feet below ground surface and the
depth of the landfill is approximately 20 feet. After drums, bulk wastes
and oontaminated soils are removed, the excavated area will be sampled
around the edges from the ground surface to 8 feet below the surface. The
sampling will determine if soils, which may pose an exposure risk from
ingestion or direct contact, have been removed. If necessary, more soils
will be removed until the exposure risk is eliminated.
The excavated area will be backfilled with materials similar to native
soils and graded and seeded.
Ground water in the water table aquifer will be collected with two
interceptor trenches. Ground water in the alluvial, semi-confined bedrock
and confined bedrock aquifers will be collected with extraction wells.
The collected ground water will be treated on-site in a granular activated
carbon system. If necessary, additional pre treatment of ground water will
be implemented, see alternative 6. The estimated volume of contaminated
ground water. is 40 to 70 million gallons.
After treatment the effluent will be discharged to Oormeaut Creek.
The cleanup levels to meet risk objectives for the ground water are the
same as in alternative 7.
Excavation, backfilling, interceptor trenches, extraction wells and GAC
treatanent are4 easily implemented.
2. Orjit"^ T i m»-TTh components
This alternative does not include any containment components.
3. Institutional Controls
Access to the site will be controlled by installing a fence. The fence
will surround the source area, the drum staging area to prepare materials
for shipment, and the ground water treatment system.
Deed restrictions will be placed on property overlying the source area and
contaminant plume to prohibit installation or use of drinking water wells
in the three aquifers identified at the site.
After removal and transport of buried drums, bulk wastes and contaminated
soils, no long term monitoring of the landfill will be necessary.
Once ground water risk objectives are met, long term monitoring will not
be necessary because the source of contamination has been removed.
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15
4. Estimated tine for Implementation
Excavation and transport are expected to take 2.5 to 3 years, which
includes design, bid, removing drums, bulk wastes and contaminated soils,
transport to an incinerator and backfilling the excavated area.
Preparation activities for ground water collection, treatment and
discharge would take 1.5 to 2.5 years for testing, design, bidding and
•traction activities. These activities would be concurrent with source
area remediation. 20 to 60 years would be required to collect and treat
all ground water to risk objectives (see alternative 6).
5. Costs
Estimated capital costs: $63,000,000
Estimated present worth: $67,000,000
Estimated annual O&M costs:$ 420,000
6. ARABS
Chemical specific ARARs are the same as those for alternative 6.
Action specific ARARs are listed on Table 4.
E. Alternative 9 ~ On—Site Irtcjjyra'tion. Grcupd Watpi* Tf^tat^nt
1. Treatment Components
This alternative will remove all buried drums (approximately 2,500 to
5,000 drums), bulk wastes and contaminated soils (approximately 25,000 to
30,000 cubic yards) from the source area. The removed materials will be
incinerated on-site. All drums, bulk wastes and visibly contaminated
soils will be removed until the bottom of the landfill or the water table
is encountered. However, if drums or bulk wastes are located within the
saturated zone, they will be removed. The water table is located
approximately 17 feet below ground surface and the depth of the landfill
is approximately 20 feet. After drums, bulk wastes and visibly
contaminated soils are removed, the excavated area will be sampled around
the edges from the ground surface to 8 feet below the surface. The
sampling will determine if soils, which may pose an exposure risk from
ingestion or direct contact, have been removed. If necessary, more soils
will be removed until the exposure risk is eliminated.
The materials remaining after incineration will be placed back into the
excavated area. It will be confirmed during test burns, prior to start up
of the incinerator, that the ash is able to be delisted. The area will be
backfilled with materials similar to native soils to bring it back to
original grade.
Ground water in the water table aquifer will be collected with two
interceptor trenches. Ground water in the alluvial, semi-confined bedrock
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16
and confined bedrock aquifers will be collected with extraction wells.
The collected ground water will be treated en-site in a granular activated
carbon system. If necessary, additional pretreatment of ground water will
be implemented, see alternative 6. The estimated volume of contaminated
ground water is 40 to 70 million gallons.
After treatment, the effluent will be discharged to Oonneaut Creek.
The cleanup levels to meet risk objectives for the ground water are the
same as those for alternative 7.
Excavation, backfilling, interceptor trenches, extraction wells and GAC
treatment are easily implemented.
The isplementability of the en-site incinerator is affected by the ability
to meet state and local regulations applicable to this technology.
Excavated material sampling, test burns and ash analyses will be required
prior to initiating the incineration activities. The incineration system
must meet performance ypfjfj Trcmp*r\tiz and »•>•»* emission discharge
requirements. The isplementability of the alternative also depends on the
incinerator ash being able to be delisted.
2. (\Tr\tai i Mutant* Components.
This alternative does not include containment components.
3. Institutional Controls.
Access to the site will be controlled by a fence which will surround the
source area, drum staging area, on-site incinerator and the ground water
treaboent system.
Deed restrictions will be placed on property overlying the source area and
contaminant plume to prohibit installation or use of drinking water wells
in the three aquifers identified at the site.
No long term monitoring of materials in the excavated area will be
necessary.
Once ground water risk objectives are met, long term monitoring will not
be necessary.
4. Fg*"ilTna't
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17
all ground water to meet risk objectives (see alternative 6).
5. Costs
Estimated Capital Costs: $36,000,000
Estimated Present Worth: $39,000,000
Estimated Annual O&M cost: $ 320,000
6. ARARs
Chemical specific ARARs are the same as those identified for Alternative
6.
Action specific ARARs are listed on Table 4.
IX. Summary of the Comparative Analysis of Alternatives
A. Overall Protection of Human Health and the Environment.
Alternatives 8 and 9 are the most protective of human health and the
environment. The source area drums, bulk wastes and contaminated soils
are incinerated and the ground water is collected and treated until ground
water risk objectives are met.
Alternative 7 protects the human health and the environment in the same
manner as Alternatives 8 and 9, except that long term protection of
vitrification is not certain.
Alternative 6 protects human health and the environment by containing the
source area and treating the ground water however, the risk of
contamination breaching the containment system will remain.
Alternative 1 is not protective of human health and the environment.
B. Compliance With ARARs
Alternatives 6, 7, 8 and 9 comply with ARARs.
Alternative 1 does not comply with ARARs.
C. long-Term Effectiveness and Permanence.
Long-term risks are eliminated for alternatives 8 and 9 because the source
of contamination (the source area) is removed and incinerated and ground
water will be collected and treated until it meets risk objectives.
Alterative 7 provides long term effectiveness and permanence by
incinerating the drums and vitrifying the ash and contaminated soils in
the excavated area, however the long-term effectiveness of vitrification
is not known. This alternative also collects and treats ground water as
in alternative 8 and 9.
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IS
Alternative 6 reduces risks by containing the source area and collecting
and treating ground water. However the source of contamination (the
landfill) remains, presenting a possible future risk that contamination
will breach the containment system.
Alternative 1 does not provide long +*r™ effectiveness because the risks
are not removed.
D. Reduction of Tbxicity, Mobility and Volume
Alternatives 7, 8 and 9 reduce toxicity, mobility, and volume of the
source area and ground water contamination.
Alternative 6 reduces mobility of the source area by containing it and
reduces toxicity, mobility and volume of ground water contamination by
collecting and treating ground water.
Alternative 1 does not reduce toxicity , mobility or volume of
contamination.
E. Short-Term Effectiveness
Alternatives 7 and 9 present a high risk to human health and the
environment during incineration but this can be reduced by the application
of engineering controls. Implementation of both alternatives will take
approximately 2 to 2.5 years. These alternatives meet risk objectives.
Alternative 8 presents a moderate risk during incineration because
incineration will be done off -site. Implementation will take 2.5 to 3
years. This alternative meets risk objectives.
Alternative 6 presents minimal risks to the human health and the
environment. Implementation will take 1.5 to 2.5 years. This alternative
meets risk objectives however the source area will remain, presenting a
future risk.
Alternative 1 does not present any risks to the public because no
remediation will occur. Risk objectives will not be met.
F. Inplementability
Alternatives 6 and 9 are easily implemented and the technologies are
proven.
Alternative 8 may present an implementation problem because only one RGRA-
permTcted incinerator is currently located near the site.
Few contractors are available to implement vitrification for alternative
7.
Alternative 1 does not involve any technologies which will be implemented.
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19
G. GOSt
Estimated Estimated Estimated
Capital Present Annual
Costs Worth Costs O&M Costs
Alt. 1 $ 0 $0 $ 0
Alt. 6 $5,000,000 $8,000,000 $ 360,000
Alt. 7 $36,000,000 $39,000,000 $ 350,000
Alt. 8 $63,000,000 $67,000,000 $ 420,000
Alt. 9 $36,000,000 $39,000,000 $ 320,000
H. State
The Ohio EPA concurs with the U.S. EPA's chosen alternative to remediate
contamination at the site.
I. Community Acceptance
A public meeting was held in Kingsville, Ohio on August 8, 1989. During
the meeting the community expressed general acceptance of the proposed
remedial alternative. Specific concerns included additional monitoring of
residential wells, community safety during excavation and incineration and
the exact location of ground water collection trenches north of the site.
Response to comments submitted by the public during the public comment
period are presented in the Responsiveness Summary Section.
X. The Selected Remedy
The selected remedy to address contamination at the site is alternative 9 which
involves excavation of buried drums, bulk wastes and contaminated soils in the
source area (see Figure 3). All drums, bulk wastes and visibly contaminated
soils will be removed until the bottom of the landfill or the water table is
encountered. However, if drums or bulk wastes are located within the saturated
zone, they will be removed. The water table is located approximately 17 feet
below ground surface and the depth of the landfill is approximately 20 feet.
After all drums, bulk wastes and visibly contaminated soils are removed, the
excavated area will be sampled around the edges from the ground surface to 8
feet below the surface. The sampling will determine if soils, which may pose
an exposure risk from ingestion or direct contact, have been removed. If
necessary, more soils will be removed until the exposure risk is eliminated.
The non-combustible material and ash remaining after incineration will be used
as backfill material in the excavated area as long as the ash is able to be
delisted. Backfill similar to existing strata will be put in the excavated
area. The top two feet of backfill will be soil which will be graded and
seeded so to allow infiltration of precipitation and aid movement of any
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20
remaining contaminants out of the native soils to the ground water
System.
The ground water oollection system will collect ground water in the water table
aquifer with two interceptor trenches; one at the downgradient edge of the
plume and one at the north end of the source area, see Figure 4. The exact
placement of the trenches will be decided after completion of a pre-design
ground water study. This study will involve confirming what was presented in
the RI, south of the site, and installing and sampling additional monitoring
wells which will better define the geology north of the site and will determine
how far contamination has migrated from the site.
The study will initially concentrate on the area north of the site where the
plume may have migrated. This area will be determined based on ground water
modelling. and results from the last round of ground water sampling during the
RI. If ground water contamination has not migrated to this theoretical point,
additional wells will be installed closer to the source area until the
boundary of the plume is identified. Conversely, if contamination has
migrated beyond the theoretical limit, additional wells farther from the source
area will be installed in order to place bounds on the location of the plume.
The full extent of migration will be established prior to designing the ground
water collection and treatment system.
Ground water in the alluvial and semi-confined bedrock and confined bedrock
aquifers will be collected with 30 extraction wells. During the pre-design
ground water study, the bedrock units will be sampled and the nydrogeology of ,
those units will be confirmed. The collected ground water will be treated with
granular activated carbon en-site and discharged to Oonneaut Creek. If it is
determined, during a pilot field test or a bench scale test that additional
pretreatment, such as sand filtration, ozonation or air stripping, is necessary
to achieve removal efficiencies of certain ^-np-m-rig, the system will be
adjusted accordingly.
Ground water monitoring wells will be installed north of each interceptor
trench to monitor for any contamination bypassing the trenches. The existing
sliallow and deep wells on the lower portion of the site will monitor for any
contaminant migration bypassing the extraction wells. A collection time of 20
to 60 years will be required to reach ground water cleanup levels in the water
table aquifer. This estimate is based upon the anrmnt of time necessary to
remove contaminants from the saturated portion of the aquifer immediately below
the source area and all contamination which has already migrated from the
source area. If contaminant concentrations change over time, the sampling
program may be modified. Cleanup levels for the alluvial/bedrock aquifer
should be met within 3 years.
Surface water monitoring will be implemented at 3 locations in Conneaut Creek
(one upstream, one downstream, and one adjacent to the site) .
The site risk objectives, which alternative 9 will meet, will reduce risks
posed by contamination in the ground water to a cumulative Hazard Index of 1.0
or less and a cumulative carcinogenic risk of 10"6 or less.
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21
XI. Statutory Determinations
A. Protection of Human Health and the Qrviron
The selected remedy will eliminate risks posed by contamination in the source
area. These risks will be eliminated by incinerating the contents of the
landfill. Risks posed by ingestion of ground water at the site will be
eliminated by a ground water collection and treatment system.
Short-term risks to the community could be introduced by inhalation of air
emissions £1011 excavation or on-site incineration, or by direct contact with
excavated material or contaminated surface water run off. Air emissions will
be monitored and would be reduced by air pollution control systems when
necessary. Risks from direct contact would be reduced by controlling site
access. Surface water runoff controls would reduce the potential for
contaminant migration from staged materials.
Workers would be in Level B protection during excavation activities.
Protection against dermal contact and inhalation would be provided during
staging, sampling, and loading activities as required. Air monitoring would
assist in determining which activities require worker protection and the level
of protection required.
B. Attainment of ARARs
The selected remedy is expected to attain all ARARs. The one problem which may
arise is if the incinerator ash is not able to be delisted and backfilled in
the excavated area. If the ash is not delistable, it will have to be handled
as a H^Ta-p^"8 waste. The selected remedy assumes that the characterization of
the ash will allow the State of Ohio to waive their solid waste regulation
regarding the final deposition of the ash. The State of Ohio has agreed to
consider such a waiver when analysis of the ash is available.
The following chemical specific ARARs will be met by the selected remedy;
Barium . MCL = 1,000 ug/L
Chromium MCL = 50 ug/L
1,4-Dichlorobenzene MCL = 75 ug/L
Trichloroethene MCL = 5 ug/L
Vinyl Chloride MCL = 2 ug/L
The remedial action risk objectives for the site are based on reducing health
risks posed by contamination in the ground water to a cumulative Hazard Index
of 1.0 or less and a cumulative carcinogenic risk of 10~^ or less.
Table 5 presents the individual concentrations of indicator chemicals which
will be used in omitting the cumulative risks for ground water and the upper
8 feet of the source area soil.
The Agency has not identified location specific ARARs.
Action specific ARARs which apply to the selected remedy are listed on Table 4.
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22
C. Cost Effectiveness
The selected remedy is cost effective. It is protective of human health and
the environment, attains ARARs and provides long-term protectiveness. The
long-term protectiveness is achieved by excavation and incineration of the
source area and treatment of contaminated ground water. The selected remedy is
less costly than alternative 8 while providing equal protectiveness.
Alternative 1 is less expensive than the selected remedy however alternative 1
does not provide overall protection of human health and the environment and
does not attain ARARs. Alternative 6 is less expensive than the selected
remedy however this alternative does not provide long-term protectiveness of
human health and the environment. In alternative 6 the source of contamination
is not removed but contained, which presents a possible future risk of a breach
of the containment structure. Alternative 7 is the same cost as the selected
remedy however the selected remedy is easier to implement.
D. Utilization of Permanent Solutions, and Alternative Treatment Technologies
of Resource Recovery Technologies to the Maximum Extent Practicable.
The selected remedy was ftetw-nnTvaH to be the most appropriate solution to
remediate the contamination at the site. The selected remedy is protective of
human health and the environment and eliminates long-term risks by removing
and incinerating the source area contamination. Alterative 8 is also equally
protective and eliminates risks but the selected remedy is more cost
effective. The selected remedy poses risks to the public and workers during
implementation of the source area excavation and incineration (2 to 2.5 years
duration) however, once this is completed the risks from the source area are
eliminated, the toxicity, mobility and volume of the source area are eliminated
and the protection of human health and the environment are mavjTtam because the.
future risks of contamination from the source area is eliminated (compare to
Alternative 6) .
Ground water collection and treatment will eliminate risks posed to the public
within 20 to 60 years, eliminate toxicity , mobility and volume of
contamination in the ground water and will maximize protection of the human
health and the environment. If the source area is not removed (see
alternative 6) , ground water cleanup will take an infinite amount of time if a
breach of the containment structure occurs. The estimated time to collect and
treat ground water, 20 to 60 years, is based upon the amount of time necessary
to remove contaminants from the saturated portion of the aquifer immediately
below the source area and all contamination which has already migrated from the
source area.
Once ground risk objectives are met, long term monitoring will not be
necessary.
Source area and ground water remediation are easily implemented and proven
technologies (compare to alternative 7) .
The selected remedy complies with ARARs.
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23
E. Preference for Treatment as a Principal Element
The selected remedy vises treatment as a principal element to remediate risks
posed by ground water contamination and source area contamination.
Treatment of the source area will involve excavating buried drums, bulk wastes
and contaminated soils followed by incineration of these materials en-site.
Treatment of the ground water contamination will involve collecting ground
water from the three aquifers identified en-site and treating ground water with
granular activated carbon.
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Table 1
Maximum Concentration Detected
Inorganics
barium
beryllium
lead
nickel
Source Area
(ng/kg)
154
=,
21.7
136
34
Soils
(nq/kg)
204
1.5
28
25
45
Ground
Water
(ug/L)
3,813
3
132
146
134
Surface
Water
(ug/L)
76
1.5
18
21
28
Organics
chlorobenzene
1,2-dichlorobenzene
1,4-dichlorobenzene
trans-1,2-dichloroethene
diaroinotoluene
trichloroethene
tetrachloroethene
vinyl chloride
Source Area
(ug/kg)
12,000,000
7,500
16,000
3,300
63,000,000
180,000
Soils
(ug/kg)
59,000
9,300
4,300
21
46
3,624
41
Ground
Water
(ug/L)
75,000
210
430
14,000
70
7,500
2,300
12
Surface
Water
(ug/L)
22
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TABLE 2
EXPOSURE PATHWAYS AND EXPOSED POPULATIONS
(UNDER TWO SITE USE SCENARIOS)
EVALUATED IN THE ENDANGERMENT ASSESSMENT FOR
THE BIG D SITE
(Page 1 of 2)
EXPO*ure Pathway
Exposed Population
Preaent Uie
Commenta
Direct Contact with Surface
Water
Incidental Ingestion of Surface
Water
Ingestion of Aquatic Life
Children aad adulu 1 to 70
yean of age involved in
recreational activitiei tuch a*
bunting, fishing, swimming, or
boating along or in Conneaut
Creek adjacent to or
downgradient of the Big 0 lite.
Same a* for direct contact with
turface water above.
Children and adult* 1 to 70
yean of age ingef ting fish and
other aquatic animal* caught
Cram portion* of Conneaut
Creek adjacent to or
downgradient of the Big 0 (ife.
The human population most
likely to be exposed arc guesta
at Big D and Locuat Lane
Campgrounds, a* well a*
person* living along Creek
Road, South Ridge Road, and
Reed Road near the site.
Same a* for direct contact with
surface water above.
The human population moat
likely to be exposed are gueata
at Big D and Locust Lane
Campgrounds, pcnon* living
along Creek Road, South Ridge
Road, and Reed Road near the
site, a* well a* residents of the
City of Kingaville.
Future Uae — Construction of Houaea Of Other Buildings On-aitt
Ingeation of Soila
Children 2 to 6 yean of age
either living on-*ite or visiting
the site.
The human population moat
likely to be expoaed include:
children vacationing at either
Big 0 or Locust Lane
Campgrounds; those children
living along Creek Road, South
Ridge Road, and Reed Road; aa
well as any children living in
residences constructed on-aite
while other buildings are being
constructed on-site. Exposure
is expected to occur
approximately 96 days/year
under probable case conditions
and 160 days/year under worst
case condition*.
-------
TABLE 2
EXPOSURE PATHWAYS AND EXPOSED POPULATIONS
(UNDER TWO SITE USE SCENARIOS)
EVALUATED IN THE ENDANGERMENT ASSESSMENT FOR
THE BIG D SITE
(Page 2 of 2)
Expoiure Pathway
Expoied Population
Comment*
Future Uie — Construction of Home* or Other Buildings On-lite
Direct Contact with Soil*
Same a* for ingettion of (oil*
above.
Samcs ai for ingeition of icili
above.
Ingeation of Ground Water
Children and adulu 1 to 70
yean of age ingetting ground
water from water fupply welli
near and downgradient of the
*itc.
At the upper portion of the
lite, pound water cxiiti in
two hydraulieally unconnected
aquifer*: the water table
aquifer and the bedrock
aquifer. The human population
mott likely to b« expo*«d are
tho*e person* along Creek Road
who u*e private wellj lereened
in the water table aquifer.
At the lower portion of the
lite, ground water exiiti in
two hydraulieally connected
aquifer*: the alluvial overbank
aquifer; and the bedrock
aquifer; with recharge from the
water table aquifer. No
drinking water wclli completed
in theie aquifer* were
identified downgradicnt of the
lite.
Additional Pathway*:
The§e include the lame pathways deicribed above under Preient U*e with the
following addition. The expoied population* for theie pathwayi under future u*e
condition* will include penoni living in any reiidence* conttructed on-iitc.
Note:
See the. text for more information concerning expo*ed population* and aaiumption* uied in expotur*
calculation*.
-------
Table 3
Summary of Potential- Risks Associated With the Big D Campground
Exposure Scenario
Total Cancer Risks1
Probable
Case
Worst
Case
Ndncarcinogenic
Hazard Index2
Worst Case
Child Adult
Ingestion of Contaminated
Soil
Upper Portion of Site
Lower Portion of Site
Direct Contact with
Contaminated Soils
Upper Portion of Site
Lower Portion of Site
_3
IxlO"10
2xlO-9
3x10
5x10
-12.
-11
Inoestion of Ground Water
Upper Portion of Site
Water Table Aquifer
Bedrock Aquifer
Lower Portion of Site
Alluvial Overbank
and. Bedrock Aquifer
6x10
-6
1x10
4x10
-2
-5
6x10'
290
5.4
24
82
1.6
6.6
Notes: -1 Total Cancer Risk = Average Lifetime Dose x Carcinogenic
Potency Factor
2 Noncarcinogenic Hazard Index = Exposure Dose -j- Acceptable
Chronic Intake
3 Not Available or Not Calculated.
-------
Law, Regulation,
or Standard
Table 4
Action Specific ARAR's
Source of
Regulation
Descriotion
Type
of
ARAR
FEDERAL
Hazardous Waste
Management
System: General
CFR 260,
et.seg.
Resource
Conservation and
Recovery Act
(RCRA) standards
applicable to
generators of
hazardous waste
RCRA standards
for owners and
operators of
hazardous waste
treatment,
storage, and
disposal
facilities.
Land Disposal
Restrictions
RCRA
Subtitle C
Section
3002, 40
CFR 262
RCRA
Subtitle C
Section
3004, 40
CFR 264 and
265, and
Federal Law
71:3101
RCRA
Subtitle C
Section
3004, 40
CFR 268
RCRA regulates the generation,
transport, storage, treatment,
and disposal of hazardous
wastes. CERCLA (Section 104
(c)(3)(B) specifically requires
that hazardous substances
generated from remedial actions
be disposed of at facilities in
compliance with Subtitle C of
RCRA.
Section 262 establishes
standards for generators of
hazardous wastes. This section
requires that generators
comply with the requirements
for identification,
accumulation, recordkeeping,
and reporting.
These regulations establish
minimum standards that define
the acceptable management of
hazardous wastes. These
include the design and
operation, monitoring,
recordkeeping, closure, and
post-closure requirements for
hazardous waste management
facilities.
These regulations identify
wastes that are from land
disposal and establish
treatment requirements
necessary before these wastes
can be land disposed.
A = Applicable
R&A = Relevant and Appropriate
-------
Table 4 (cont.)
Type
Law, Regulation, Source of of
or Standard Regulation Description ARAR
EPA-administered RCRA These regulations cover the A
permit programs: Subtitle C basic EPA permitting,
The Hazardous Section monitoring, and reporting
Waste Permit 3005, 40 requirements for hazardous
Program CFR 270 and waste management facilities.
124
Standards of Clean Air These regulations establish the A
Performance for Act, 40 CFR general provisions and
New Stationary 60 performance standards for
Source stationary sources of air
emissions.
Safe Drinking Safe This Act establishes maximum A
Water Act Drinking contaminant levels (MCL) and
Water Act, MCL goals (MCLG) at levels that
40 CFR 141 would result in no known or
through 143 potential adverse health
affects. MCLs are enforceable
health goals. In addition,
this Act establishes guidelines
for secondary drinking water
standards.
Clean Water Act Clean Water This Act establishes non- A
Act Section enforceable guidelines for
301-308 water quality that, when not
exceeded, reasonably protect
human health and aquatic life.
National Clean Water This regulation sets forth A
Pollutant Act Section requirements for point source
Discharge 402, 40 CFR discharge of water into public
Elimination 122, 123, surface waters.
System (NPDES) 125, and
136
Occupational 29 CFR 1910 This Act establishes A
Safety and guidelines, requirements, and
Health Act regulations to provide for the
(OSHA) health and safety of workers
conducting remedial action
activities.
A = Applicable
R&A = Relevant and Appropriate
-2-
-------
Table 4 (cont.)
Law, Regulation,
or Standard
Source of
Regulation
Description
Type
of
ARAR
STATE
Ohio Solid and
Hazardous Waste
Disposal Law
Ohio Solid Waste
Disposal
Regulations
Ohio
Revised
Code (ORC)
3734.02(H)
Ohio
Revised
Code
3734.05(C)
Ohio
Administra-
tive Code
(OAC)
3745-27-02
OAC 3745-
27-05
OAC 3745-
27-06
OAC 3745-
27-07
This regulation prohibits
excavation and construction
activities without
authorization from the Ohio
Director of Environmental
Protection.
This regulation defines
criteria and requirements that
need to be included in a
hazardous waste facility
operating permit.
This regulation states that no
provision of 3745-27 or 3745-37
shall exempt parties from
compliance with any federal
regulation or any section of
the Ohio Revised Code.
This regulation specifies that
solid waste in Ohio must be
managed by landfilling,
incineration, compositing, or .
approved methods not prohibited
by OAC 3745-27.
This regulation requires that
the plans for new solid waste
disposal facilities specify the
design features for on-site
solid waste disposal
activities.
These regulations require that
the operator incinerate waste
materials as soon as possible
and that incinerator operations
comply with chapters 3704 and
6111.
A = Applicable
R&A = Relevant and Appropriate
-3-
-------
Table 4 (cont.)
Law, Regulation,
or Standard
Source of
Regulation
Description
Type
or
ARAR
OAC 3745-
27-08
Ohio Hazardous
Waste Management
Regulations
Ohio Water
Quality
Standards
Ohio Air
Pollution
Regulations
Ohio Particulate
Matter Standards
OAC 3745-
27-10
OAC 3745-50
through
3745-69
OAC 3745-
01 (-03, -
04, -05,
and -07)
OAC 3745-
15-07
OAC 3745-
15-16
OAC 3745-17
(-02,-05,
-07, and -
-09)
These regulations establish the
general performance
requirements for the operation
of solid waste disposal
facilities.
These regulations establish the
general performance
requirements for the closure of
sanitary landfills.
These regulations closely
parallel the federal
regulations described in 40 CFR
264 and establish minimum
standards for the acceptable
management of hazardous wastes.
These regulations establish
performance standards for the
collection of samples and
maintenance of existing surface
water. They .prohibit nuisance
discharges and define water use
and criteria that should be
maintained.
This regulation prohibits air
pollution nuisance emissions
not regulated under 3745-17,
3745-18, 3745-21, or 3745-31.
The substantive requirements of
these regulations are
applicable to alternatives that
would produce air emissions.
This regulation establishes
stack height guidelines 'for
point sources of air emissions.
These standards specify maximum
ambient air particulate levels
and establishes emission limits
for opacity and capacity.
R & A
A = Applicable
R&A = Relevant and Appropriate
-A-
-------
Table 4 (cont.)
Law, Regulation,
or Standard
Source
Regulation
De sc r i Dtion_
Type
of
ARAR
Ohio Sulfur
Dioxide
Standards
Ohio Regulations
for Carbon
Monoxide,
Photochemically
Reactive
Materials,
Hydrocarbons,
and related
materials
Ohio Regulations
for Carbon
Monoxide,
Photochemically
Reactive
Materials,
Hydrocarbons,
and related
materials
OAC 3745-18
(-02, -04,
and -06)
OAC 3745-
21 (-02, -
03, and -
-05)
OAC 3745-
21-07
These establish standards,
methods of measurement, and
allowable emission rates for
sulfur dioxide.
These regulations set ambient
air quality standards,
establish acceptable methods
for the measurement of ambient
air quality, and prohibit the
degradation of ambient air
quality set in 3745-21-02.
These regulations establish
rules to control the emission
of organic materials from new
stationary sources.
A = Applicable
R&A = Relevant and Appropriate
-5-
-------
Table 5
CLEANUP LEVELS BASED ON INGESTICN OF
INDICATOR CHEMICALS IN GROUND WATER
Ground Water Ground Water
- Concentration (ug/L) Concentrations (ug/L)
Based on Based on Upperbound
paraph Index of 1.0^ iJifi^Jn*5 ("^rv"igr P7»ks— of:
Adult Child
Exposure Exposure
SHALLOW GROUND WATER AT
UPfEK. PORTION OF THE SITE
(WATER TABLE AQUIFER)
Chlorobenzene 945 270 NA3
2,4-Diamnotoluene NA NA 1.1 x 10~2
Tetrachloroethene 700 200 6.9 x 10-1
Trichloroethene NA NA 3.2
Vinyl Chloride NA NA 1.5 x 10"2
GROUND WATER AT
UPPER PORTION OF THE STTE
(CONFINED BEDROCK AQUIFER)
Chromium (Cr/Cr) 35,000/175 10,000/50 NA
Nickel 350 100 NA
Tetrachloroethene NA NA 6.9 x lO'1
GROUND WATER AT LOWER
PORTION OF THE SITE
(ALLUVIAL OVERBANK AND
SEMI— CONFINED BECFOCK
AQUIFER)
Barium 1995 570 NA
Chlorobenzene 945 270 NA
2,4-Diaminotoluene NA NA 1.1 x 10~2
Tetrachloroethene 700 200 6.9 x 10'1
Trichloroethene NA NA 3.2
1 Based on Hazard Index - Exposure Dcse/Aoceptable Chronic Intake and
assuming an inge^tion rate of 1 L/day and a body weight of 10 kg for
children and an ingestion rate of 2 I/day and a body weight of 70 kg for
adults.
2 Based on the following assumptions for adults: ingestion rate =
2 I/day »* body weight = 70 kg; frequency of contact = 365 days; years of
exposure = 70 years
3 NA = Not applicable
-------
Table 5 (cent.)
CLEANUP LEVELS BASED ON INGESTICN AND DIRECT CCNTACT
WTIH CCNIMaNAIED SOURCE AREA. SOIL
Soil Concentrations
(mg/kg) Based on
Hazard Index of 1.0
Soil Concentrations (ing/kg)
Based on Upperbound Lifetime
Cancer Risk of
CJtl rmQtv*r"i7^*TV»
Tetrachloroethene
1 , 4-Dichlorobenzene
1 , 2-Dichlorobenzene
IngestionJ'
1.2 x 103
3.4 x 102
NA
NA
Direct
Contact2
4.1 x 104
2.7 x 103
NA
NA
NA5
1.2 X 101
23
23
Direct
Contact4
NA
3.9 X 101
7.4 x 102
7.4 X 102
on an ingestion rate of 1.0 x 10~3 kg/day for worst case and an
average body weight for children of 17 kg.
2 pag«^ on an exposure amount of 3.75 x 10~4 kg/day, an average body weight
for children of 25 kg, and a percent absorption of 5 percent for organic
11 IIB t ajjnig.
3 paean on an ingestion rate of 1.0 x 10~3 kg/ day for worst case, an average
body weight for children of 17 kg, and exposure frequency of 160 days, and 5
years of exposure.
4 Baspd on an exposure amount of 3.75 x 10~4 kg/day, an average body weight
for children of 25 kg, a percent absorption of 5 percent for organic
compounds, an exposure frequency of 144 days per year, and 12 years of
exposure.
5 NA'- Not Applicable
-------
N
loop o loop 2000 lOoo 4000 aooo
FEET
S Q
KILOMETER
IN ir.nvM 101111
HOAO Ci ASSil '1C A lion
Hldmni
liigMituly -- —
Unim|iio<«4-lnl : a = a a c.
OUAORANGU IOC»IION
NOTE: R«p>oductd from u.S.G S 1979
FIQUR E 1
TOPOGRAPHIC MAP OF
NORTH KINGSVILLE QUADRANGLE
REATED; 1/10/B9 [REVISED: 1/10/69 |dr»q
PRO ENVIRONMENTAL MANAGEMENT. INC.
-------
'19
4
Ul 6T7
665
CH ±£
il
HARD GREY CLAY TILL AQUITRD
CONFINED BEDROCK AQUIFER
COVER MATERIAL
ALLUVIAL OVERDAHK
AQUIFER
V
\SG-2
CREEK BEDROCK
AQUIFER
70S
z
o
66)
631
408 416
DISTANCE (FT)
LEGEND [ j. Suilc w«lor level |M«y'l9e7)
NoU: O1 w«i eomploUd by Olln prloi to lh« Rl.
I
SCREENED
INTERVAL
sc
I
CM
iML/CL
CL/ML
_ '
^ BR
PROJECT: BIG 0 CAMPGROUND
FILE: W64532RI
LOCATION: KINGSVILLE
FIGURE 2
GEOLOGIC CROSS SECTION
1O-SG2
PRO
JiJ«menl. loc
-------
7
/ Area to b*
/Excavated a
I Bockflll.d
Wllh A*h
LEGEND
Estimated Area of Drum Burial
and Contaminated Subeoll
_ _ _ Boundary of fence Area
300
-~- 780 ~-~
Contour Una
Contour Interval 10 feet
SCAl£ IN FEET
FIGURE 3
CONTAMINATED SOIL AND
DRUM REMOVAL FOR ON-SITE
INCINERATION
CKEA1ED: 11/16/68 REVISED: 03/03/69 ONS)Tt.OWC
PRO ENVIRONMENTAL MANAGEMENT. INC.
-------
RESPONSIVENESS SUMMARY
BIG D CAMPGROUND SUPERFUND SITE
KINGSVILLE, OHIO
SEPTEMBER 1989
Produced by
PRO Environmental Management, Inc.
and
ICF Technology Incorporated
Work Assignment No.
EPA Region
Date Produced •
ARCS Contract No.
Site No.
Site Manager
Telephone No.
EPA RPM
•Telephone No.
01-51B1
5
September 29, 1989
68-W8-0084
OHD980611735
Ron Reising
(312) 856-8700
Janice Bartlett
(312) 886-5438
-------
RESPONSIVENESS SUMMARY:
BIG D CAMPGROUND SUPERFUND SITE
KINGSVILLE OHIO
SEPTEMBER 1989
TABLE OF CONTENTS
Introduction 1
Section 1: Summary of Community Comments and U.S. EPA Responses. 2
Section 2: Summary of Olin Chemicals Corporation Comments and
U.S. EPA Responses '. 14
Section 3: Summary of Ohio Environmental Protection Agency Comments
and U.S. EPA Responses 38
Appendix A: Submitted Community Comments
Appendix B: Submitted Olin Chemicals Corporation Comments
Appendix C: Transcript of public hearing held on Tuesday, the 8th day of
August, 1989 at the Kingsville Fire Hall, Kingsville, Ohio
Appendix D: Submitted Ohio Environmental Protection Agency Comments
-------
INTRODUCTION
This document is the Responsiveness Summary for the Big D Campground
Superfund Site, located in Kingsville, Ohio. According to Superfund law,
before the United States Environmental Protection Agency (U.S. EPA) can sign a
Record of Decision, it is required to review and respond to comments received
regarding any proposed remedial action to be taken at a site. Comments from
the Kingsville community were submitted to U.S. EPA during a public comment
period that was held from July 28 to August 26, 1989 and the public comments
received are summarized on the following pages.
The Responsiveness Summary is split into three sections. Section 1
contains a summary of the comments received from community members and is
followed by U.S. EPA's response. Section 2 contains a summary of comments
received from the Olin Chemicals Corporation and also is followed by U.S.
EPA's response. Finally, Section 3 presents comments from the Ohio.
Environmental Protection Agency and U.S. EPA's responses. In addition, the
appendices include copies of all comments submitted as well as a transcript
from the public hearing held on August 8, 1989 in Kingsville, Ohio.
Each summarized comment is followed by an alpha-numeric reference code
indicating the source of the comments. The key to the reference code is as
follows:
A) "Transcript of public hearing held on Tuesday, the 8th day of
August, 1989, at the Kingsville Fire Hall, Kingsville, Ohio."
Following the letter "A" is the page number, followed by the line
number.
B) "Comments on the RI/FS Reports Big D Campground Superfund Site,"
Submitted by Olin Chemicals Corporation, August 25, 1989.
Following the letter "B: is the page number.
C) Comments from Mr. and Mrs. Norma Thorpe, August 8, 1989.
D) Comments from Tim Baird, August 8, 1989.
E) Comments from Tracey Dreslinski, August 8, 1989.
F) Comments from the Ohio Environmental Protection Agency.
-------
SECTION 1: SUMMARY OF COMMUNITY COMMENTS AND U.S. EPA RESPONSES
Adequacy of Sampling and Monitoring
Comment: We live directly south of the dump and want our soil and water
tested. No one has ever tested it. [C]
U.S. EPA Response:
The soils and ground water which were found to be contaminated at the site are
not connected to soils and ground water south of the landfill (south of the
Creek). The erosion of the Creek has caused the separation. The Creek has
eroded soils down to the deep bedrock which eliminates the pathway of soil
contamination moving south of the Creek. Ground water flow also is
interrupted by the Creek. The Hydrogeologic Investigation conducted during
the RI shows that ground water flows toward and into the Creek, therefore
cross-contamination of ground water cannot occur.
In addition, during the Remedial Investigation, two residential wells were
sampled south of the Creek. The results of this sampling did not indicate
that any contamination has migrated south of the Creek. No soil sampling was
conducted off-site in residential areas.
U.S. EPA does not feel it is necessary to test any ground water or soils on
property south of the Creek because a pathway for migration does not exist.
Comment: We support the Remedial Alternative #9 and hope that U.S. EPA can
proceed to implement it as soon as possible. Until you do start the
procedure, we would hope you would do more frequent water and soil testing.
We suggest that you test all parties in the immediate area of the site, and
make the test results available to them. [C]
Will drum samples or well sacples be taken during the remedial action?
[A,73,14}
U.S. EPA Response:
U.S. EPA sampled six residential wells in May, 1987 and the Ohio Environmental
Protection Agency (Ohio EPA) conducted limited residential well sampling in
September, 1988. These residential wells did not exhibit any ground-water
contamination; however, U.S. EPA recognizes the need for further monitoring of
residential drinking water wells.
U.S. EPA and Ohio EPA will arrange further sampling of residential drinking
water wells north of the Creek, primarily on Creek Road. The results of this
sampling event will be sent to the owners of the wells sampled. During the
-------
remedial action, ground water will be monitored to insure that the contaminant
plume does not bypass the northern interceptor trench and the extraction wells
by the Creek. Sampling of drums to be removed from the landfill will be
conducted prior to incineration during the remedial action.
Comment: When was the last time Mr. Baird's well was sampled? Mr. Baird's
well was not sampled by Ohio EPA six months ago. [D]
U.S. EPA Response:
Mr. Baird's well, located at 3740 Creek Road, was sampled by the U.S. EPA in
May, 1987. During this sampling round, the owner's name was listed as
"Ramison".
Comment: Ve are concerned about those residents who have wells that are
inside the defined plume area. Apparently the State did some sampling less
than six months ago, but not all of the wells were sampled. Ue need to be
assured that all the wells in the area are safe for us to use. [A,23,14]
D.S. EPA Response:
The plume area was defined based on numerous pieces of information, such as
known concentrations of contaminants found in wells around the landfill, the
ground-water flow direction and the type of soils the water is moving through.
However, sampling done at the selected homes indicates that contamination is
not present. In addition, during sampling events at residential wells, it was
observed that the water table was very shallow (approximately five feet deep)
compared to the water table on-site which is located at approximately 15-20
feet below the surface. This difference in water levels indicates that the
residential wells are probably screened in a perched aquifer which is
separated from, and above, the water table aquifer identified on site.
In order to verify that contamination of ground water has not occurred, U.S.
EPA and Ohio EPA will arrange to conduct further sampling of residential wells
north of the site, primarily on Creek Road. The results of this sampling
event will be sent to the owners of the wells.
An additional ground water study will also be conducted to determine exactly
where ground water contamination is located; how far it has migrated from the
site. This study will involve installing more monitoring wells and sampling
these wells to determine the extent of contamination.
Comment: It seems that U.S. EPA did not collect enough soil samples to
accurately characterize the effect of site contamination on the soil.
[A.25,20]
-------
U.S. EPA Response:
During the RI soil samples were collected from nine borings around the
landfill. These samples were selected based on screening with an organic
vapor detector. The general sampling locations were Just above the water
table, just below the water table, just above the. hard grey till geologic
unit, and at the base of the hard grey till unit. U.S. EPA feels these
samples characterize the soil contamination on site.
Comment: U.S. EPA doesn't know what's in the landfill. [A,68,6]
At one point, Olin Chemicals Corporation was scared about thylene gas leaks.
It killed people working for them. [A,66,20] U.S. EPA says that it has no
written information on whether thylene is in the .landfill. U.S. EPA should be
able to get Olin Chemicals Corporation to say what is in the landfill.
(A,67,10]
We don't know what's dumped in that landfill because U.S. EPA cannot get a
hold of Olin Chemicals Corporation or cannot press them into telling us what
is in that landfill, and I think you better get on the ball here and try to
find out what's in there, how far that landfill is going to seep into
everybody's property along Creek Road--across Conneaut Creek and do something
about it, because we haven't done anything about it so far. [A,86,17]
U.S. EPA Response:
On December 2, 1985, U.S. EPA sent letters to several companies in Kingsville
and Ashtabula, Ohio, including Olin Chemicals Corporation. These letters
requested all information the companies may have had concerning the operations
at the Big D Campground site.. Responses to those letters identified wastes
which were disposed of in the landfill. Olin Chemicals Corporation identified
four RCRA listed hazardous wastes which were disposed of in the landfill:
centrifuge and distillation residue from toluene diisocyanate (TDI)
production; benzene, 1-3-diisocyanatomethyl; chlorobenzene; toluenediamine
(TDA). In addition, Olin identified the following materials which may have
been transported to the site for disposal: spent vacuum pump oils, TDI
residue contaminated with monochlorobenzene (HCB) and carbon tetrachloride,
earth contaminated with TDA and TDI spills, flyash, trash, monoethanolamine
(MEA), off-spec TDI, and TDA and TDI in sample cans and bottles. The vacuum
pump oil may have been contaminated with TDI, MCB and trace phosgene.
Thylene was not identified as having been put in the landfill.
During the RI, two test pits were excavated in the landfill to verify the
presence of buried drums and other wastes. This sampling confirmed that there
are materials similar to what Olin described, i.e., buried drums and bulk
wastes, in the landfill. During this excavation several samples of drum
contents, contaminated soils and other wastes were taken to characterize the
type of contamination in the landfill. This sampling identified that
contamination from the materials in the source area was similar to that found
in the ground water and soils and that the contamination is migrating away
-------
from the landfill.
Ground Water
Comment: If U.S. EPA just used a computer model to project the location of
the groundwater plume, then you have no specific evidence from monitoring
veils. [A,74, 23] When it coxes time to install the trenches and the
groundwater monitoring system, if the groundwater plume has been defined to be
larger, then it is not necessary to install those trenches where you show
them. They may very well be much closer to the actual site. [A,75,5] If it
takes two trenches to do the job, they could both be located south of the
homes. [A,75,14]
U.S. EPA Response:
The computer model which estimates the location of the ground-water plume uses
the concentrations of contaminants detected in the monitoring wells to
estimate the extent of the plume. See pages 4-18 of the RI report, which
discusses that the level of contamination of chlorobenzene was used to
determine the extent of the plume.
The location of the northern extraction trench will depend on the extent of
the plume, which will be determined after further ground-water study. This
trench will be installed at the downgradient (northern) edge of the plume. If
it is determined that the northern edge of the plume is south of the homes on
Creek Road, the northern trench will be located south of the homes.
Comment: The plume area is just an estimated area, and it seems that the
plume could be moving in another direction. When will U.S. EPA know for sure
the exact area of contamination so that a remedy can be designed? It appears
that U.S. EPA could have collected more samples do accurately define the areas
of contamination. [A,24,15]
O.S. EPA Response:
The direction of ground-water flow determines the direction of movement of the
contaminant plume. Ground-water movement was determined based on water level
measurements taken during the RI. See the RI report page 3-7 for details.
A further ground-water study will be conducted to determine a more precise
extent of ground-water contamination.' This study should be completed within
the next year and one half and will provide information necessary to place and
construct the ground-water cleanup system.
The ground-water samples which were collected during the RI identified that
ground-water contamination does exist and that the source of contamination is
the landfill, from which the contamination is migrating. The RI ground-water
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study was conducted to obtain this information. When the RI was in the
planning stages, it was not known in what direction ground water was flowing,
what type of contamination existed, or the geology of the site.
Comment: Isn't it true that Olin Chemical Corporation, at some point,
placed a clay cap over the site and has a monitoring well.and run-off trench
that are still in place? [A,45,12] It must be true that whatever
contamination has taken place through groundwaier seepage took place prior to
1983 or 1984 when Olin Chemicals Corporation put the clay cap on the waste and
installed the water collection trench. [A,46,2]
U.S. EPA Response: .
In December, 1978, Olin Chemicals Corporation installed three wells near the
Creek (see RI, Page 1-12). In December, 1983, Olin installed 11 additional
monitoring wells. In March, 1983, Olin submitted evidence to U.S. EPA that it
covered, regraded, and seeded the landfill. The wells and cover are still in
place.
The earliest sampling done by the U.S. EPA was April, 1982, which identified
ground-water contamination. While it is not known exactly when contaminant
migration occurred, the potential for migration has existed since the first
wastes were deposited and will continue for as long as wastes remain.
Comment: I would like more information about the ground-water treatment
plant. How long will it be in place? [A,56,8] How long will it be in
operation? [A,56,24]
We are the people who are living in those houses that will be between the
trenches. People will be working and digging and going in and out of there
for 20 years. It will change out whole quality of life. [A,57,7]
I am concerned about the location of the trenches. I'd like to know where
they are going to be before I make a comment on the Proposed Plan. I'd hate
to see the trenches go south through the row of homes where I live. [A,101,18]
I think that people should be immediately reimbursed for any damage to their
property that U.S. EPA causes when the trenches are being built. [A,102,19]
I worry about the property values. Since this has come out in the Star Beacon
anybody people perceive that property values around the site are worth squat.
Nobody is going to by that property now. When U.S. EPA get done, will all the
property owners get an affidavit saying that the property is safe and that
property values have been restored?
I'm an independent real estate appraiser. I'm not directly affected as the
property owners are, but I'm going to be indirectly affected because I'm going
to end up appraising some of the properties in the area. The Federal Home
Loan Bank made a statement pertaining to values. The Federal Home Loan Bank
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has issued a memorandum or a statement that now as an independent appraiser I
have to notify on the appraisal report of any property that's within one mile
of a Superfund site. I don't want to speak for the underwriters, but when
they see a situation like this, to me that means a big red flag, and I guess
there's going to be some type of value diminished. This is a big project for
a small community to fathom. [A,116,6]
U.S. EPA Response:
The ground water collection system will collect ground water in the water
table aquifer with two interceptor trenches; one- at the downgradient edge of
the plume and one at the north end of the source area. The exact placement of
the trenches will be decided after completion of a pre-design ground-water
study. This study will involve installing and sampling additional monitoring
wells which will better define the geology north of the site and will
determine how far contamination has migrated from the site.
The trenches will be in place for approximately 20-60 years. The trenches
will be installed underground to a .depth of approximately 25 feet, will be
filled with a permeable material to collect ground water, and should not be
noticeable after they are reseeded. Once the trenches are installed and
operational, personnel will not be "working and digging and going in and out"
of resident's property because the ground water collection process is done by
the trenches. Personnel will only be required to work on the trenches for
regular maintenance checks or if a problem arises with the ground-water
collection system. Personnel will be working in the ground-water treatment
plant which will be located on the site.
U.S. EPA and Ohio EPA will attempt to design the placement of the trenches to
minimize the impact to residences in the vicinity of the trenches. The
agencies will attempt to repair to its original condition any property that is
damaged during installation of the trenches.
Ground water in the alluvial and semi-confined bedrock and confined bedrock
aquifers will be collected with 30 extraction wells. The collected ground
water will be treated with granular activated carbon on-site and discharged to
Conneaut Creek.
Ground-water monitoring wells will be installed north of each interceptor
trench to monitor for any contamination bypassing the trenches. The existing
shallow, and deep wells on the lower portion of the site will monitor for any
contaminant migration bypassing the extraction wells.
A collection time of 20 to 60 years will be required to reach ground-water
cleanup levels. This estimate is based upon the amount of time necessary to
remove contaminants from the saturated portion of the aquifer immediately
below the source area and all contamination which has already migrated from
the source area. If contaminant, concentrations change over time, the sampling
program may be modified.
The site will be fully cleaned up once the landfill contamination is
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incinerated and the contaminated ground water clean up is completed. The
agencies will then remove the site from the National Priorities List and will
it will no longer be a Superfund site.
U.S. EPA cannot guarantee that property values will not be affected. The
primary purpose of U.S. EPA is to protect public health and the environment.
The Agency believes that the selected remedy will best address environmental
impacts and future health risks posed by site conditions. U.S. EPA will
attempt to minimize other impacts posed by the remedy.
Comment: Suppose U.S. EPA finds contamination in water wells, then what
happens? How will we be provided with water if the water wells are found to
be contaminated? [A, 70,17]
What we were told before was that if they found any wells that are .
contaminated, U.S. EPA would hook everyone into either Conneaut or Ashtabula,
and Olin Chemicals Corporation would have to pay for it. Does that still
stand? [A,71,7]
U.S. EPA Response:
If contamination migrates from the site and is discovered in residential
drinking water wells, U.S. EPA, in conjunction with Ohio EPA, will provide an
alternate drinking-water source. 'One way to provide an alternate drinking-
water source would be to hook-up residents to a nearby municipal water source.
The U.S. EPA would try to get the PRPs to pay for the hook-up. If necessary
the U.S. EPA would pay the costs and attempt to regain costs at a later date
from Potentially Responsible Parties (PRPs).
Distribution of Information
Comment: Information from U.S. EPA should be sent to all Kingsville
residents concerning the Big D Campground site, especially if there should
ever be an evacuation. [C] If U.S. EPA continues to take samples, conduct
tests, and monitor the residents that live nearby should be notified.
(A,40,2)
U.S. EPA Response:
The U.S. EPA mailing list for the site was established based on interest shown
by residents who attended public meetings held in 1987 and 1989. Whenever new
information is released to the public or a public meeting is scheduled, a
notice is published in a local paper to advise all residents. The U.S. EPA
will advise residents living near the site of work scheduled to be conducted
on-site.
Any evacuation plan, which would be prepared by U.S. EPA would contain the
8
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names, addresses, and phone numbers of all residents in the immediate vicinity
of the site.
Incineration
Comment: I am concerned about the proposed incinerator. The specifics of
the incinerator must be explained to the community. For example, will the
incinerator have a scrubber as part of the system? [A,23,7] What type of
incinerator will it be? [A,31,18] Is there going to be a lot of noise during
operation of the incinerators? [A,82,13]
U.S. EPA Response:
The U.S. EPA will mail a fact sheet on incineration to all persons on the
mailing list. As soon as the specific incinerator to be used is chosen,
further information will be sent to the residents on the mailing list and, if
interest warrants, a meeting will be scheduled to provide additional
information.
Exeavat ion
Comment: The wind primarily comes out of the. northwest and I live downwind
from the site. As you plan to dig up material at the site that will be
incinerated, precautions must be taken. Is there any danger to the people who
live downwind of the site while U.S. EPA is digging up and transporting
contaminated material? [A,22,9]
U.S. EPA Response:
Air monitoring will be conducted during excavation to ensure on-site worker
protection and to monitor the air quality near the site for residents.
Comment: You are proposing excavation, but at a prior public meeting we
were told that if the wastes were just dug up, there could be more problems,
like another Love Canal. Now, if you go in there and start digging won't you
have the same concerns? [A,58,9}
U.S. EPA Response:
The RI report identifies types of contaminants at the site. Information on
the types of wastes placed in the landfill also has been obtained from Olin
Chemicals Corporation. There is no indication nor any reason to believe that
this site will turn into another Love Canal. However, safety precautions and
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contingency plans to handle any emergency situations will be established prior
to beginning any excavation work at the site.
Comment: During the excavation activities, it seems that there should be an
independent party that monitors the contractors. [A,88,16]
How many U.S. EPA employees will actually be on the site? Does U.S. EPA
actually do some of the testing? [A,79,12]
We are concerned about U.S. EPA's power to make sure that the cleanup is done
properly. [A,49,21]
U.S. EPA Response:
During the design and construction phases of the project ahead, the U.S. Army
Corps of Engineers will have a leading role. In the actual removal and
incineration phases of the project, the Corps will procure the contractors and
provide the necessary oversight as well. U.S. EPA and Ohio EPA's role will be
assure that any public health threat is addressed, that the public is informed
of the progress of site clean up and that U.S. EPA's Record of Decision is
carried out in full. If the responsible parties implement the cleanup, U.S.
EPA and the Corps will provide oversight of all activities pursuant to a
court-entered Consent Decree.
It is not possible to estimate how many persons will actually be on site
during any one phase of the remedial action.
Contingency Plans *
Comment: I am concerned that U.S. EPA's Proposed Plan does not contain
contingencies to address problems that may still occur. For example, suppose
that during the excavation process some of the drums burst, what would happen?
[A,33,24]
U.S. EPA stated that if something unexpected happens it will be eventually
detected through monitoring activities. We are concerned about residents in
the area of the site in the event that something happens, like leaking toxic
vapors. What happens to nearby residents until the excavation takes place?
[A,35,5] If something goes wrong at the site, say that gas is coming off the
site at a higher level than it should, we want to know that U.S. EPA won't
delay in fixing the problem. [A,51,24] We are concerned about your
contingency plans so that we can be assured that the cleanup will be conducted
properly. [A,69,18]
U.S. EPA Response:
During the remedial design, contingency plans will be prepared to handle
10
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emergency situations which may occur during the remedial action. As soon as
an emergency situation was detected, which would entail excavation or some
other measure, residents would be notified. The U.S. EPA would not neglect to
tell residents of an emergency situation as its purpose is to protect human
health and the environment.
Once the remedial design is completed, prior to beginning the remedial action,
the design plans and related documents will be made available to the public at
the repository located in the Kingsville Public Library.
General
Comment: Alternative #9 says that you are going to prohibit the use of the
water wells. Is that what you're going to do? Everybody has a well. [A.^72,3]
The fact sheet says,"...EPA would prevent the use or installation of
groundwater supply wells in the area of the site..." [A,72,15]
U.S. EPA Response:
The use or installation of drinking water wells located in the contaminated
aquifer will be prohibited. If contamination related to the site is found in
residential drinking-water wells, the U.S. EPA, in conjunction with the Ohio
EPA, will provide an alternate drinking-water supply. ^The actual extent of
the contaminated ground-water plume will be better defined after completion of
the additional ground water study.
Comment: I would like to know why U.S. EPA does not give the community any
direct answers. U.S. EPA says "I'm not sure," or, "we're going to have to
monitor more." Why doesn't U.S. EPA have someone talk to the community who
knows more about the site and understands the issues. [A,88,23]
I think that the representatives from the U.S. EPA here.tonight have tried to
divide and conquer these people by stating, "that later on we will answer your
questions on a one-to-one basis."
It is really hard for me to be in favor or not in favor of a remedial plan
when we don't have any specific information. U.S. EPA can't tell us where the
trenches are going to be placed or the location of the plume. How can the
community make a comment on this? We don't know who's going to be affected by
this. [A,95,15]
I think that before we accept or disapprove anything we should have a field
representative or an engineer from the U.S. EPA who is familiar with this
area, who is familiar with the dump, who knows what's going on, to come out
and explain the issues to the people of Kingsville. [A,100,11]
When such time as you people come back with a solid workable plan then I'll
give a comment on whether I feel it's to my benefit or not. I believe that
11
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you should have another meeting when you come back with a solid plan, not Just
a proposal. [A,102,11]
U.S. EPA Response:
At the public meeting, the only types of questions which U.S. EPA deferred to
be answered later or were not able to answer were either specific questions
posed by residents living near the site, i.e., issues such as standing water
in their backyards, and specific questions on the remedial action, or the
location and type of incinerator to be used on-site. Information about
residential concerns was not known prior to the meeting. If U.S. EPA and Ohio
EPA had been aware of these concerns prior to the meeting, these questions
could have been researched. The design specifications of the remedial action
will be developed during the remedial design phase. Therefore it was not
possible during the Proposed Plan public hearing to tell the community exactly
where the interceptor trenches will be located, or what type of incinerator
will be used on site, and what type of scrubber it will have. During the
remedial design phase all the specifics of the remedial action will be
decided. Once the remedial design is completed the remedial action cleanup of
the site will begin.
The RI and Feasibility Stu
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Comment: We are concerned chat U.S. EPA will pick another less protective
alternative for addressing contamination issues at the site. [A,41,7] If
funds run out, U.S. EPA may pick a cheaper remedy. [A,43,2]
U.S. EPA Response:
The Proposed Plan discusses U.S. EPA's preferred alternative for cleaning up
the site. Once the Record of Decision (ROD) is signed the remedy is finalized
and cannot be changed without notifying the public, beginning a second public
comment period for the new remedy and signing another ROD.
If funding problems occurred, the remedial action may be slowed but U.S. EPA
would not choose a cheaper remedy simply to save money. The remedy chosen
with this ROD is the most cost effective and protective of human health and
the environment.
13
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SECTION 2: SUMMARY OF OLIN CHEMICALS CORPORATION COMMENTS AND U.S. EFA
RESPONSES
Acetone
Comment: The organic compounds detected in the deep wells are primarily
acetone, methene chloride, and chlorobenzene. Section 4.3.3 of the RI report
notes that acetone, methylene chloride, chlorobenzene, toluene, and
trichlorethylene were detected in some field and/or laboratory blanks up to
305.8 ppb of total VGA's. Acetone was used as a rinse in decontamination of
ground water sampling equipment. This is especially troubling since acetone .
is the compound reported in the highest concentrations and with the greatest
frequency in the deep wells. [B,2]
U.S. EPA Response:
Only one field blank sample had other organic compounds than acetone and
methylene chloride (field blank sample BD-FB2-01). This was a field blank of
a bladder pump which was not used in sampling any of the deep wells. As
stated in the RI report, the compounds found in field blank samples were
compared to the analytical results and, when appropriate, the analytical
results were eliminated from consideration. Furthermore, neither acetone,
methylene chloride, or toluene were used in calculating potential risks.
•
Comment: Section 4.3.3.3 of the RI states "Acetone, a common field and
laboratory contaminant was the only compound detected during both sample
rounds in a single-deep well." If acetone is not included, the detected total
VOA concentrations in the deep wells exceed 10 ppb only in one sample (34.2
ppb in the first sample from Well 4D). The latest measurement from Well 4D
was 0 ppb. [B,3]
U.S. EFA Response:
Table 4-5 in the RI report identifies acetone separately in the distribution
of organic contaminants at the site. Total VOAs are not listed. As stated
above, acetone was not used in calculating potential risks.
Ground Water
Comment: Chemical data presented in the RI report about ground water from
the confined bedrock aquifer raises serious concerns with respect to the
validity of the RI data. Specifically, we are concerned about the following:
14
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1. Validity of the ground water samples and analysis from the deep
wells (those screened in the unit designated the confined bedrock
aquifer) is questionable.
2. Significance of the low, inconsistent concentrations detected in
the deep aquifer is doubtful.
3. Temporal patterns in the data suggest that the concentrations in
ground water from the deep wells may result from residual
contamination introduced to this depth by drilling for
installation of the monitor wells.
4. Well development was not sufficiently defined and may not have
been properly done. [B,2]
U.S. EPA Response:
U.S. EPA does not believe that there is any problem with the data obtained
from deep wells.
The significance of low concentrations of contaminants found in the deep
aquifer is important. Tetrachloroethene found in one deep well has a 5.1 x
10'6 cancer risk. . .
All deep wells were constructed by properly casing off the upper aquifer
followed by continued drilling into the deep aquifer using equipment not used
in the water table aquifer (as discussed in Appendix A of the RI report).
Temporal patterns may be indicative of pulses of contamination being released
from the landfill. Well 2D showed an increase in chlorobenzene concentrations
between round 1 and. 2.
Wells were developed using a surge block coupled with repeated bailing and
pumping (as discussed in Appendix A of the RI report). U.S. EPA believes well
development was conducted properly.
Comment: The spanned period of four months, for well sampling and analysis,
is insufficient to make ground-water quality conclusions. The data for
repeated samples from any single deep well is inconsistent. For example,
subsequent samples resulted in the following total VOA concentrations.
well ID 0 to 76 ppb
well 2D 1,100 to 118 to 0 ppb
.well 3D 628.6 to 48 to 0 ppb
well 4D 71.2 to 900 to 0 ppb
well 5D 5,922 to 0 ppb
well 6D 430 to 38 ppb [B,3]
In the last ground-water sampling event, four of the six wells did not report
any detectable VOAs. Even if the sampling and analysis results were not of
15
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questionable validity the data would not necessarily demonstrate contamination
of the confined bedrock aquifer. The data for total VOAs listed above
illustrate a general trend of decreasing concentration with succeeding
samplings.
U.S. EPA Response:
The deep well analytic! results are not inconsistent. As discussed above, it
is not unusual for contaminants in the ground water to move in pulses which
will vary the concentration of contaminants found in the ground water
throughout the year.
In addition, the total VGA concentrations listed in this comment are not
correct. Wells 2D, 3D, and 4D did not show 0 ppb total VOAs in the last
sampling event. As discussed in the footnotes of Table 4-10 of the RI report,
these samples were analyzed for extractables but not analyzed for volatiles.
Comment: Dedicated sampling equipment should have been used to avoid
problems of equipment contamination during sampling. Because of the presence
in the blank samples of the same contaminants reported to be present in the
samples and the inconsistent results from repeated samplings, the ground-water
sample and analysis results do not indicate significant concentrations of
organics in the deep ground water. [B,3]
Thi's suggests that the detected organic compounds could be the result of
contamination from shallower zones that was carried into the deeper aquifer
during drilling for installation of the deep monitor wells. Repeated purging
and sampling of a well would gradually reduce the constituent concentrations
resulting in lower detected concentrations with repeated samplings and perhaps
invalidate the conclusion that no deep contamination exists. [B,4]
U.S. EPA Response:
The field blank sample which showed organic compounds other than methylene
chloride and acetone (BD-FB2-01) was'a sample from a bladder pump. This
sampling pump was not used to sample the deep wells. All other field blank
samples indicate that decontamination procedures were adequate and did not
introduce organic compounds into the samples (with the exception of acetone
and methylene chloride which are common lab contaminants).
Comment: It should be noted that in comparing production well contaminant
concentrations with site monitoring-we11 concentrations in the same aquifer,
lower concentrations may occur in dynamic systems such as production wells in
comparison to stagnant systems such as monitoring-wells. The use of
monitoring well data applied to production well consumption may overstate the
health risk. [B.15]
16
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U.S. EPA Response:
In order to prevent sampling of "stagnant systems", purging is done prior to
sampling. Furthermore, MCLs are based on water quality from a "tap" or
faucet.
Comment: The data in Appendix C of the RI report does not indicate the
volume of water that was removed from each well during development and during
purging for each sampling event. This information is necessary to evaluate
the validity of the ground water samples. [B-4]
U.S. EPA Response:
Five to 40 gallons of water were removed from the deep wells during
development, 15 to 60 gallons were removed from the shallow wells during
development, and 25 to 70 gallons were removed from the creek wells during
development. The exact quantity removed was dependant on well yield. In all
cases, wells were developed until the water form the wells was clear and as
sediment-free as possible. Conductivity, pH and temperature were also
monitored.
Comment: Boreholes 2D, 3D, and 4D were advanced 10 to 20 feet deeper than
the planned well depth. On attempting to plug the bottom of these boring
cement bentonite grout rose in the borehole through the screened interval,
Borehole 2D was apparently properly plugged and abandoned and the well was
installed in a new borehole adjacent to the first location. Borehole 3-D,
however, was drilled out using a core barrel. Borehole 4-D was flushed with
water to remove the rout. The adequacy of the measures for wells 3-D and 4-D
is questionable and residual grout in the wells may impact quality of water
samples from these wells. The procedure used for the borehole 2-D should also
have been used for 3-D and 4-D. [B,4]
U.S. EPA Response:
The U.S. EPA decided not to abandon and redrill wells 3D and 4D because the
wells were able to be redrilled through the grout (3D) and flushed (4D). It
was determined that the presence of grout would not impact the quality of
samples acquired from these wells.
Comment: Northward movement of shallow ground water is stated as fact.
This is not documented and is not justified by the data in the RI report.
Table 3-1 (p.3-16 of the RI report) shows some higher ground water elevations
north of wells IS, 5S and 4S. For example, water levels in 3S, the northern
most monitor well, and RW3 (a residential well located about 600 feet north of
the reported ground water divide at the site) were 712.90 feet and 719.83*.
feet, respectively, on September 26, 1987, and higher than the wells
immediately.to the south. In fact, the ground water elevation was higher in
17
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the northern most shallow monitor well, MW-3S, than in well to the south of it
on four of the six dates on which ground water elevation measurements were
reported. Ground-water elevation in RW3 was 720.07 feet msl on May 16,1987,
higher than monitor wells located to the south. Furthermore, it is difficult
to predict a contour of 714 feet as shown in Figure 3-3 (p.3-8 of the report)
with the existing ground-water elevation data. This contour was drawn
considerably north of well 3S, the northern most monitor well and the northern
most data point. Also, the water level around the 712 feet contour line in
Figure 3-4 (p.3-9) can be interpreted in other ways. For instance, an east-
west trough could exist instead of a closed depression. [B,8]
U.S. EPA Response:
U.S. EPA interprets ground-water movement in the water table aquifer is to the
north. This is substantiated by the water level measurements taken in
monitoring wells on-site, and presented in Table 3-1 of the Rl report. Water
level measurements obtained from residential wells are not used to contour
ground-water flow because the ground water in residential wells has different
characteristics from ground water in monitoring wells on site (determined from
review of inorganic data and the use of modified stiff diagrams). In
addition, northern flow of the shallow ground water is substantiated by the
presence of contamination from the landfill being detected in all shallow
ground-water monitoring wells north of the landfill.
Contour line 714 on Figure 3-3 of the report was drawn only 75 feet north of
well 3S and was estimated using standard contouring techniques. Contour line
712 on Figure 3-4 could indicate and east-west trough but is not supported by
any data collected during the RI. The U.S. EPA believes that the ground-water
flow interpretations presented in Figures 3-3 and 3-4 are appropriate.
Comment: In the modeling of the plume, it has been assumed that the water
table aquifer is infinite in extent. This assumption is contradictory to the
actual physical characteristics. In fact, data were not presented that verify
that the aquifer is continuous in .the area included in the model. Also the
model did not account for the vertical recharge from the surface. [B,ll]
U.S. EPA Response:
The model was used as a tool to estimate the extent of contamination based on
existing site data. The assumption of an infinite aquifer and no vertical
recharge are common assumptions in analytical models. These assumptions were
noted in the selection of the model and the results are accordingly used as
just one tool in remedy selection.
Comment: The Princeton Model is limited to modeling a single source with a
single ground-water flow direction. The study used a combination of results
from multiple model runs as a weighted average of concentration with respect
to discharges from the two source areas. Theoretically, since it is not based
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on solute mass balance or mass conservation, the weighted average
concentration may deviate remarkably from the true value at each location. It
is, therefore, essential to verify the results by running other models
(analytical or numerical) and comparing the results. No indication of model
verification was submitted.
In light of the above, we suggest that the following be considered further:
1. Obtain water level data for additional dates and provide more data
points further north.
2. Utilize another analytical model to verify the Princeton Model's
results with the same given assumptions;
3. After adequate data is obtained, refine the assumptions and use
other analytical or numerical models to obtain results based on
more realistic physical conditions. A numerical model or
combination of analytical and numerical models is highly
recommended since it can better simulate the subsurface conditions
at the Big D site;
4. Sensitivity analysis of the responses of ground water flow and
contaminant transport with respect to changes in the
hydrogeological parameters is essential since the input values are
based on assumed values and may differ very significantly from the
actual conditions. No sensitivity analysis is reported in the RI.
[B.12]
U.S. EFA Response:
Confirmation of ground-water data was not determined to be necessary during
the RI/FS because U.S. EPA will be obtaining further information on ground-
water flow and the extent of the plume during a pre-design study, as discussed
in the FS and ROD. This study will involve confirming what was presented in
the RI report, south of the site, and installing and sampling additional
monitoring wells which will better define the geology north of the site, the
ground-water flow, and how far contamination has migrated from the site.
The study will initially concentrate on the area north of the site where the
plume may have migrated. This area will be determined based on ground-water
modelling and results from the last round of ground-water sampling during the
RI. If ground-water contamination has not migrated to this theoretical point,
additional wells will be installed closer to the source area until the
boundary of the plume is identified. Conversely, if contamination has
migrated beyond the theoretical limit, additional wells farther from the
source area will be installed in order to place bounds on the location of the
plume. The full extent of migration will be established prior to designing
the ground water collection and treatment system.
Comment: The estimated extent of shallow ground water contamination to the
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north of the site is based solely on the predications from the analytical
model and actual ground water data are limited to the southern edge of the
area modeled. Contradictions exist between the model and-the available data
and numerous unverified assumptions are present in the analytical model and
the estimation of contaminant extent. Evaluation of the extent of
contamination requires collection of actual hydrogeologic and water chemical
data within the area modeled. The actual extent may vary significantly from
what has been predicted in the RI report, as is indicated by the available
data for residential wells. [B.13]
U.S. EPA Response:
The limitations of the ground-water model are discussed above. Ve agree that
residential well water quality data does not support the northern extent of
the plume. That is the purpose of the pre-design ground water study which the
U.S. EPA will conduct to define the extent of the contaminant plume. Based on
the information gathered during this study, the actual placement of collection
trenches and extraction wells can be designed.
In addition, soil gas sampling was conducted to assist in verifying the
location of the modelled plume. This investigation detected target compounds
in the soil gas in areas -of the predicted plume extent north of any ground-
water sampling point (see Appendix J of the. Rl report).
Comment: Table I of Appendix H of the RI report lists the ground.water
velocity used in the model as 3.64 x 10scm/sec. This equivalent to about
1,030,000 feet per day. Presumably this is a typographical error. What
ground water velocity was used? [B,13]
U.S. EPA Response:
The correct velocity used in the model is 3.64 x 10"5 cm/sec.
Comment: The data presented in the RI report is not adequate to verify that
the shallow, aquifer is continuous to the north of the site. Additional
measuring points are necessary to define the direction of the ground water
movement from the site. [B,8]
U.S. EPA Response:
It is appropriate to assume that the aquifer is continuous because there is no
evidence to indicate otherwise. As discussed above, an additional study of
the extent of the plume, the ground water and the geology north of the site
will be conducted during a pre-design study prior to finalizing the remedial
design.
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Comment: Page 3-7 of the RI report states that since the unusually low
water table elevations in the fall do not represent normal site conditions,
ground-water flow systems have been discussed using May 1987 data. If this is
the case, ground-water flow to the north would be primarily uni-directional as
indicated by Figure 3-3. This is contradictory to the two-lobed contaminant
plum used in the analytical model and depicted in Figure 4-6 (p.4-19 of the RI
report). The pattern of a two-lobed plume could be simulated under the
initial condition of two-directional ground water flow as depicted in Figure
3-4 (p.3-9 of the RI report). With the available data, the conclusions
arrived at on p.3-7 and p.4-18 of the RI report regarding the northward
movement and the two-lobed plume are not substantiated. It should be noted
that seasonal fluctuations in the ground water elevation occur even in normal
precipitation years and the measurements during the RI may reflect normal
trends although the actual elevations would vary from year to year. It is
possible that the northern portion of the site exhibits a seasonal reversal of
flow direction. [B,8]
U.S. EPA Response:
The flow direction in figure 3-3 and 3-4 are not markedly different. The test
pit investigation indicated the presence of two separate source areas which
are divided by undisturbed soils. In addition, ground-water level
measurements and contamination detected in all wells north of the landfill
indicate northern movement of ground water. The presence of a northern plume
of contamination was verified by soil gas sampling. If a seasonal reversal of
flow direction does occur, it does not change any conclusions reached by U.S.
EPA.
Comment: ' Page 4-12 of the RI report states that well RU-3 "is probably not
screened in the same water bearing unit as the monitoring wells at the Big D
site. Well construction, recharge rates, and static water level indicate this
well receives water from a localized perched water table zone." The basis for
this conclusion is not documented in the RI. The data presented in the RI
report (Table 1 of Appendix C) does not distinguish the aquifer at RW-3 from
that at RW-1, RU-2, RU-4 and the onsite monitor wells completed in the water
table. Table 1 of Appendix C (see volume II of Final RI Report) lists RW-3,
RW-1, RW-2 and RW-4 as screened in the overburden (assumed based on
discussions with owners). No hydrogeologic analysis or other data is
presented to indicate that RW-3 is not screened in the same aquifer as the
other residential wells or the shallow onsite monitor wells. The ground water
elevation in RW-3 is higher than in the northern most shallow onsite monitor
wells and this may reflect a ground-water elevation surface for the water
table different from that assumed in the RI rather than necessarily indicating
a different aquifer. It should be noted that the RI report also indicates
that the water table aquifer onsite is a perched aquifer in the over burden.
[B,8]
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U.S. EPA Response:
The discussion regarding the water-bearing unit in which RV-3 is screened,
applies to all residential wells. The discussion on page 4-12 of the Rl
report only mentioned well RW-3 because inorganic contaminants were detected
in this well. The basis for the conclusion is information obtained by
utilizing modified stiff diagrams which indicate a different ground water
chemistry in residential wells compared to on-site monitoring wells. The
water table aquifer on-site is not a perched aquifer because an unsaturated
zone does not exist below this aquifer. However a perched water table aquifer
was discovered during the soil gas investigation at sample number SG-19 (see
Appendix J of the RI report, p.4).
Comment: According to the RI report, one of the stated reasons for the two-
lobed contaminant plume is surface water recharge from the drainage swale at
the northern end of the site. If the drainage swale is a significant source
of recharge, the local ground water flow would be expected to be southward
from the south side of the swale and northward from the north side of the
swale (i.e., a ground water divide). This is contradictory to the statement
in the RI report that ground water moves northward. [B.10]
U.S. EPA Response:
The effect of the drainage swale does not appear to be significant in altering
ground-water flow to a degree which could be seen in ground-water elevations
obtained during the RI. However, as stated in the RI report, the drainage
swale may be one reason for the two-lobed plume.
Comment: Residential well RW2, located at 3700 Creek Road, does not show
any chlorobenzene contamination or other contamination believed to come from
the site. However, Figure 4-6 shows that the computer simulation predicts
that there is about 3mg/l of chlorobenzene in the vicinity of RV2. The
detection limit for chlorobenzene is .005mg/l. The accuracy of the transport
model is implied in the RI report to be about one order of magnitude, but in
this case is in error by at least a factor of 600. The assumptions on which
the model is based may not be valid. [8,10]
U.S. EPA Response:
This comment is not clearly understood because RW2, located at 3700 Creek
Road, is not shown on Figure 4-6 of the RI report. U.S. EPA assumes that this
is a typo, and the comment applies to RW3.
RW3 was not installed by U.S. EPA and is therefore not constructed for the
purpose of monitoring the water table aquifer. As discussed above, evidence
indicates that this well in installed in a perched aquifer above the water
table aquifer.
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Soil
Comment: Two background soil samples were collected, both from the same
location. The RI then states that "As shown in Table 4*1 the highest borehole
concentrations for all compounds except silver exceeded the concentrations
detected in the two background samples. The highest concentrations of each
inorganic compound detected in the test pits- exceeded the concentrations in
both background samples with the exception of antimony, arsenic, beryllium,
cobalt, iron, cyanide, selenium, thallium, and vanadium." These are true
statements, however, it should be noted that this does not necessarily
indicate elevated concentrations in the soil borings and test pits relative to
the two background samples. Most of the inorganic constituents analyzed are
present in varying concentrations in soil samples as a result of natural
processes. The naturally occurring concentrations will vary from location to
location and will exhibit a statistically distributed range of values which is
dependent on the number of samples of the total population of samples which
have been analyzed. That is, if the range for a very small number of samples
is compared to the highest value observed from a much greater number of
samples collected from the same population, it is expected that some values
will exceed the range of the small number of samples. Since many more samples
were analyzed from boreholes and test pits than from background locations, it
should be expected that some values will exceed the range exhibited by the
background samples. Note that the lowest concentrations of the borehole and
test pit samples for the inorganic constituents are also lower than or equal
to (for not detected) that lowest values for the two background samples. The
comparisons used and conclusions reached are statistically invalid. [B,10]
U.S. EPA Response:
Inorganics in the soil pose no significant risks with the exposure scenarios
evaluated for this site.
Comment: Soil gas concentration contours have not been provided to help
evaluate the validity of the estimated extent of the ground-water
contamination plume, as shown in Figure 4-6 of the RI report (p.4-19).
Further verification of the results is necessary. [B.ll]
U.S. EPA Response:
Limited sampling points, extreme stratification of the soils, and wet
conditions prevented U.S. EPA from confidently contouring soil gas data.
As state above, additional pre-design studies of the ground water north of the
site will be conducted.
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Risk
Comment: Por Tables in chapter 6, the upper bound excess lifetime cancer
risk value mathematically should be reported with three significant digits to
obtain more uniform calculation results. Also, in the selection of soil
ingestion rates - the soil ingestion values presented in the EPA Superfund
Exposure Assessment Manual (SEAM) p. 168, Table A-5 are presented by age group
and are more accurate. The information in this reference also provides time
periods for various ingestion rates making the assumption of years of soil
ingestion unnecessary. [B,13]
The worst case soil ingestion of IxlO*3 was selected. Is the basis for
selecting this value valid? See page 6-5. [B,26]
U.S. EPA Response:
The Superfund Public Health Evaluation Manual (SFHEM) suggests that the upper
bound cancer risk be reported with one significant figure. The assumption for
soil ingestion and the use of a IxlO*3 kg/day soil ingestion rate are based on
a U.S. EPA directive issued on January 27, 1989.
Comment: The scenario used regarding direct contact with contaminated soils
extent of exposure (p.6-6) assumes that future direct contact with soils will
involve soil up to 8 feet below the ground surface. The basis of the
assumption (depth of 8 feet rather than surface soil) needs to be presented.
Use of surface soil would probably result in significantly lower exposure.
The exposure via this pathway is zero. [B,14]
U.S. EPA Response:
The assumption for future soil exposure assumes that houses will be
constructed at the site and soil will be excavated to eight feet to install a
basement (p. 6-2 to 6-3 in RI).
Comment: On page 6-6 of the RI report, the potential dermal exposure is
estimated to be 1 ng soil/cm2 body area. This estimate is high, a value of
0.6 mg soil/cm1 is more accurate (Lepow, 1975). The value of 1 mg soil/cm2
overestimates the health risk and this should be stated. The Superfund Public
Health Evaluation Manual (SPHEM) states that the uncertainties of each
assumption make during the risk evaluation process and the resulting over or
underestimation of health risk must be clarified. Evaluation of the impacts
of assumptions was not made for any exposure assumptions. [B,14]
U.S. EPA Response:
The U.S. EPA chose the value of 1 mg/cm2 to be a median value. The commentor
24
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cited a value of 0.6 mg/cm2 while U.S. EFA's Superfund Exposure Assessment
manual cites (Harger 1979) values of 1.45 mg/cma for potting soil and 2.77
mg/cm2 for clay, the U.S. EPA believes 1 mg/cm3 to be a reasonable compromise
between the various literature values.
Comment: The basis for the selection and use of an additional carcinogenic
potency factor for calculating dermal exposures was not stated. The impact of
the use of these factors in addition to the use of factors developed for
ingestion of contaminants on the overall risk estimate was not discussed.
[B.14]
U.S. EPA Response:
The use of potency factors for dermal exposures is based on the fact that a
percentage of the chemical will pass across the skin and enter the blood
stream. Therefore U.S. EPA applied an absorption factor to the dosage
calculation which reflected the amount (percentage) that would cross the skin
barrier and enter the blood stream.
Comment: It is stated on page 6-11 of the RI report that the sampling
results for the residential wells did not reveal any inorganic or organic
contaminants that could be attributed to releases from the Big D site. It
should have been stated that for incomplete exposure pathways there is no
actual risk. (See Reference SPHEM, Page 36, first column, second paragraph).
There is no potential risk associated with the site ground water at this time
due to an incomplete exposure pathway. Risk is overestimated because it is
assumed that the pathway is complete at this point. The potential for future
risk exists only if a production well is placed in a location completing the
exposure pathway. [B,15]
U.S. EPA Response:
The RI report acknowledges that no one is currently exposed and that the risks
are based on the assumption of future exposure. The risks are estimated based
on a series of assumptions for future exposures associated with contamination
of nearby residential wells or drinking water wells completed on-site or off-
site at some time in the future. Actual or threatened releases of hazardous
substances from the site may present an imminent and substantial endangerment
to public health, welfare, or the environment if contaminants in the landfill
and migrating from the landfill are not addressed.
Comment: When referring to risk, it should be clarified in the RI report
that the future is based on a period of 70 years for risk assessment purposes,
not an infinite time period. [B.15]
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U.S. EPA Response:
An exposure may last longer than 70 years. This time frame is used to
estimate lifetime risk from exposure. If the source is not removed, it is
possible that exposure could continue for longer periods.
Comment: The RI report states that both acute and chronic exposures for the
potential ingestion of ground water were evaluated. Only chronic hazard index
values can be found in the RI report. [B.15]
U.S. EPA Response:
Only chronic hazard indices were evaluated. The statement "Potential
ingestion of ground water ... was evaluated ... for both acute and chronic
exposures" (p.6-12 of RI report) relates acute and chronic exposures to
noncarcinogenie and carcinogenic effects, respectively.
Comment: For infrequently found contaminants, geometric mean concentrations
were not calculated and the contaminant was not evaluated under probable
conditions. In order to evaluate these contaminants under probable case
conditions, the geometric mean can be calculated utilizing a concentration
equivalent to one-half the detection limit for that specific contaminant when
there are "non-detectable" levels. This approach more accurately estimates
the actual or probable exposure. [B,15]
U.S. EPA Response:
The assumptions used by the U.S. EPA exclude the infrequently found
contaminants from analysis under the probable case exposure. This also
assumes that these contaminants will not cause an unacceptable risk under the
probable case exposure. In addition, risks have already been identified in
ground water, this method would only increase the risks already identified.
Comment: It is stated in the RI report that extrapolations from animal
studies do not address human-animal differences in absorption. This is not
true - all effect levels obtained from chronic animal studies are multiplied
by a safety factor of 10 to account for interspecies variation. It is also
states that the ACI and CPF calculations assume that the human body absorbs
100Z of the contaminant, the same extent as an experimental animal. For most
compounds this is not true. The reasons for excluding the percent contaminant
absorbed in equations 6-1 and 6-2 in the RI report are not satisfactory.
However, by assuming 100Z is absorbed, the estimated dose is higher and the
calculated risks are more conservative. [B,16]
The RI states that IX inorganic and 5X organic dermal exposure assumptions
would be used, these percentages are used in equations 6-1 and 6-2 in Appendix
H of the RI report. [B.16]
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U.S. EPA Response:
The assumption made by U.S. EPA was that no adjustment in the dosages for
ingestion exposure would have to be made to account for the absorption rate in
man. The ACI and CPF are based on a dose ingested or administered not on a
dose absorbed into the blood stream. Although 100X is absorbed into the blood
stream, the U.S. EPA assumed that inorganic contaminants would absorb into the
blood stream at a rate that is one percent of the rate of absorption via
ingestion. This absorption for organics was five percent.
Comment: The BCF values quoted for chlorobenzene range from 10 to 4185. A
value of 465 was selected and the basis for this selection is not stated. A
more conservative approach would be to use the highest value. Recalculations
using BCF of 4185 gives a HI of 0.32 which is still in the acceptable range.
[B.16]
U.S. EPA Response:
The BCF chosen by U.S. EPA related to the species found in Conneaut Creek.
Comment: In chapter 6 of the RI report, the estimated dose and HI should
have been calculated for barium, lead, and beryllium. [B,16]
U.S. EPA Response:
The U.S. EPA felt that it was appropriate to only perform qualitative analysis
of these contaminants due to a lack of good BCF data for these metals.
Comment: The estimated dose for chlorobenzene is 9.5E -01 not 9.21 E 01
nigAg- (See page 6-16 of the RI report) The HI is 3.5 E -02 not 3.4 x E -02.
[B.17]
U.S. EPA Response:
The error is noted. The risk is still not significant.
Comment: In Appendix H of the RI report it is stated that exposure dose is
equal to 10,230 mgAg exposure dose should equal 10.230 mg/kg °r 10,230 ug/kg-
[B.17]
U.S. EPA Response:
The exposure does should be 10,230 ugAg/day and tnis value was used in all
27
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calculations.
Comment: A discrepancy exists in the average body surface area of a child
used in the risk assessment. Although EPA (1985) stated the average surface
is 1200 cm3, the 1988 Superfund Assessment Manual (Page 127} quotes that the
dermal area of a child is 9400 cm2. [B.18]
U.S. EPA Response:
The difference between sources is noted. However, the existing risk is well
below the acceptable range and using the newer value would lower the dose and
resultant risk even further.
Comment: The derivations and calculations of the carcinogenic potency
factors and noncarcinogenic acceptable daily intake values should be discussed
in more detail. In addition a discussion of the safety factors included in
the calculations should be included. This information is necessary to
determine the validity of the conclusions. [B,18]
U.S. EPA Response:
Since this information is readily available from U.S. EPA's IRIS data base, it
was not included within the report.
Comment: Two of the ADI values i.e. those for barium and beryllium which
were used in tha study differed from the values quoted in the 1986 EPA
Exposure Manual. If some other source was used, it should be referenced. In
the case of barium, the value differed by 11X but in the case of beryllium,
the figure used, 5.00E-03, was one order of magnitude less sensitive than the
value of 5.00E-04 quoted in the 1986 EPA manual. In the text it was inferred
that a 1987 revision of the Toxicity data was the source of some of the ADI
values. A full reference to this manual was not made as a footnote to the
appropriate tables. [B,18]
U.S. EPA Response:
The full reference is given under footnote (a) in the table.
Comment: Risks were evaluated on future site use (residential scenario).
Risk associated with present use needs to be discussed.
U.S. EPA Response:
At present none of the residential ground water wells at the site are
contaminated with chemicals related to the site. Therefore, no completed
28
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human exposure route exists at the Big D site and no risks were calculated for
present exposures.
Comment: The procedure to calculate the exposure dose is different - the
intake factors defined below are not the same. Why are 'these values
different?
Intake factor - exposure dose
maximum concentration [B,25]
U.S. EPA Response:
U.S. EPA followed the general procedures for calculating exposure dosages
found in U.S. EPA's Superfund Health Evaluation Manual. This document calls
for two different methods for calculating dosages - one for exposure to non-
carcinogenic chemicals and another for exposure to carcinogenic compounds.
Comment: Calculations for worst and probable case conditions for soil
ingestion utilized maximum and mean concentrations as well as frequency of
exposure. Calculations for worst and probable case conditions for water
ingestion utilized maximum and mean concentrations and frequency of exposure
was excluded. The use or non-use of a frequency factor requires explanation.
[B.25]
U.S. EPA Response:
The U.S. EPA assumed that the water ingestion would be relatively uniform in
the exposure scenarios given and therefore did not include frequency of
contact as a factor in the calculations.
Comment: It is stated that the environmental exposure considered the most
likely to occur is the ingestion of aquatic life that inhabits Conneaut Creek.
No rationale was presented to support this statement, nor was the risk for
this exposure route calculated. Please explain. [B,2S]
U.S. EPA Response:
The exposure route at the site that could occur under the present conditions
is the ingestion of aquatic life. People catch and eat fish caught in
Conneaut Creek. As discussed in the RI report the potential risk to human
health from ingestion of aquatic life from Conneaut Creek is virtually zero.
Comment: The rationale for including the factor frequency of contact (days)
in the exposure dose equation of 365 days (6-1) is not clear. Frequency of
exposure is not generally considered in calculating a hazard index. [B,26]
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U.S. EPA Response:
Since U.S. EPA focused on the chronic exposure to non-carcinogenic chemicals,
the EPA felt that it was appropriate to average the exposure dose over a one-
year (365 days) exposure. It was felt that if the dose was calculated by not
taking into account frequency of contact this could overestimate the exposure
to these chemicals.
Comment: The WQC for chlorobenzene was quoted as 7.2E-04 ug/L for
consumption of drinking water and aquatic organisms and 7.4E-04 ug/L for the
consumption of aquatic organisms only from a 1980 EPA reference. A more
recent reference, EPA SPHEM, 1986, gives WQC value of 488 ug/L for
chlorobenzene for both consumption of aquatic organisms and drinking water and
for the consumption of drinking water only. [B,26]
The VQC for chlorobenzene taken from a 1980 EPA reference is 7.2E-04 and 7.4E-
04. The EPA manual gives a value of 488. [B.26]
U.S. EPA Response:
The mistaken value reported was for hexachlorobenzene, the correct value for
chlorobenzene is 488 ug/L. The correct value was used" in the comparison, so
no change in the text is needed (see p. 6-26 of RI report).
Test Pits
Comment: On page 4-3 of the RI report it is stated that "based on the
results of the test pit excavation the estimated volume of contaminated fill
is 25,000 to 35,000 cubic yards." Were the fill estimates actually made from
conversations with the transporter, from the geophysics, or from the test
pits? It is not clear. The actual calculations and assumptions used should
be presented. [B.19]
On page 4-3 of the RI report landfill volumes are "estimated from the
geophysical survey to be 35,000-52,000 cubic yards." There is no discussion
upon which that statement is based. [B,19]
U.S. EPA Response:
The estimated volume and location of the source area is based on information
from the transporter, the generator, geophysical survey, and test pits. The
actual volume will only be known when excavation is complete.
Comment: On page 7-1 of the Summary of Conclusions of the RI report, the
statement is made "Based on the geophysical survey and the test pit excavation
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results, it is estimated that there are two source areas with a combined
volume of 25,000 to 35,000 cubic yards." Supporting documentation for this
conclusion was not found. [B.19]
U.S. EPA Response:
The estimated volume of the source area is discussed above. The
identification of two possible source areas was determined based on the test
pit investigation. The test pit investigation indicated the presence of two
separate source areas which are divided by undisturbed soils. However, this
will not be confirmed until excavation is in progress.
Drums
Comment: In the FS report, several references to the RI report are made
(pp. ES-3, 1-31, 2-5, etc.) stating "that 2,500-5,000 drums may be buried
within the suspected drum boundary" inferred from the aforementioned fill
volumes. No documentation correlating either the geophysical results to the
fill volumes, or the geophysical results to a total number of buried drums was
presented in the RI or FS reports. Again; the calculations and assumptions
used to obtain this estimate should be provided. Also, the geophysical survey
detects metal pieces, rods, etc., which might be present in the soil. These
might influence the results to a great extent and might have erroneously been
interpreted as indicating the presence of drums. The report makes no mention
of such possible errors. [B,20]
U.S. EPA Response:
The number of drums estimated to be in the source area is based on discussions
with the transporter. The transporter indicated that from the mid-60s to the
mid-70s, he may have transported over 6000 drums of liquid to the site. The
test pit investigation indicated that fewer drums may be in the source area.
For estimating purposes, a range of 2500 to 5000 drums was selected. Until
the landfill is excavated, the exact number of drums can not be determined.
Remedial Alternatives
.Comment: Table ES-1 indicates that alternative 6, source area containment,
treatment of ground water outside contaminated area, complies with all ARARS
and is protective for soils and ground water. It also indicates that it is
easily implemented with proven technologies. Table ES-1 indicates that
alternatives 2 and 6 have minimal risk during remediation, alternatives 4 and
8 have moderate risk and alternatives 3, 5, 7, and 9 have high risk.
Alternative 6 also is indicated as requiring relatively short time to
implement. Of the alternatives developed in the FS, Alternative 6 appears to
have distinct advantages during the remediation when the risk for release to
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the air of relatively high concentrations of contaminants is much lover than
for other alternatives. The only disadvantage listed for Alternative 6
relative to some other alternatives is that the long term risk (presumably of
release of slow moving contaminants to ground water) is expected to be higher.
Such releases can be detected by monitoring and since the ground water moves
very slowly, allows considerable time for corrective measures before human
exposure would occur. The short term risk of exposure to relatively high
concentrations from fast moving air releases during alternatives requiring
extensive excavation allows little time for response and appears to represent
the greater risk to human health. [B,20]
U.S. EPA Response:
U.S. EPA has determined that the selected remedy is the most appropriate
solution to remediate the contamination at the site. The selected remedy is
the most protective of human health and the environment, eliminates long term
risks, reduces toxicity, mobility and volume, is easily implemented and
complies with ARARs. The selected remedy poses risks to the public and
workers during implementation of the source area excavation and incineration
(2 to 2.5 years duration) however, these short-term risks can be reduced by
application of engineering controls and, once the incineration is completed,
the risks from the source area are eliminated. Alternative 6 does not reduce
toxicity or volume of the source area and dees not provide long-term
protectiveness of human health and the environment because the source area
will not be removed. Slurry walls have an expected lifetime of 30 years. If
a breach of the slurry wall occurs, ground-water monitoring should detect it.
However, as long as source materials are allowed to remain within the water
table the chance for migration exists. Numerous reconstructions of the
containment system may need to be implemented before the total risk is gone.
With the selected remedy, once the source area is removed no additional
releases of contamination could occur and the direct contact of source
materials with the water table is removed. Only contamination which has
already migrated from the source area would need to be collected and treated.
And, once the source area is removed and incinerated and ground water risk
objectives are met, long term monitoring will not be necessary.
Comment: Onsite incineration will require a high volume flow of water for
operation. The discussion of incineration does not identify the source or
discuss the availability of this water and the associated cost. Ready
availability of this volume of water is questioned since discussion of a soil
bentonite slurry wall barrier on page 3-55 indicates that water for
construction of the slurry wall would have to be obtained from an unspecified
off site location. Availability of the larger volume of water for onsite
incineration is thus questionable. [B,21]
U.S. EPA Response:
The volume of water required for incineration cannot be determined until the
incinerator is selected during the remedial design. The source of water
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needed for incineration will be determined during the design phase of the
remedial action.
Comment: During screening of remedial technologies all
solidification/stabilization techniques except in situ vitrification were
eliminated. It appears that one technology was not considered and' that other
technologies were eliminated without adequate test data. The technology now
exists to use large diameter augers through which a stabilization fixation
slurry is pumped. The auger mixes the slurry with the waste material and
contaminated soils, drums would be ruptured and the contents fixed within the
slurry. This technology is not subject to the same limitations as the other
solidification/stabilization technologies listed on Figure 2-1. In addition,
other stabilization techniques were eliminated based on questions of
effectiveness and possible leaching. Bench scale tests should have been
completed prior to elimination to determine if effective treatment mixes are
available. In addition, excavation and offsite incineration of intact drums
combined with stabilization of the soil and ruptured drums should be
considered. It does not appear that these alternatives were considered.
[B.24]
U.S. EPA Response:
The solidification technologies suggested are not proven technologies and were
eliminated from further consideration for that reason.
Comment: Neither the description of each alternative nor the cost estimate
table for each alternative present adequate detail to determine if all
essential elements of the alternative have been considered and to determine if
the cost estimates are consistent and accurate. [B,2S]
U.S. EPA Response:
The estimates list the elements that comprise the total costs. The costs
estimates were used to compare alternatives and have an expected accuracy
between -30 to +50 percent, as discussed in the FS report, p. 4-2.
Incineration
Comment: The area allocated for incineration in each onsite incineration
option as illustrated on the referenced figures appears to be substantially
less than that required by available transportable incinerators with the
required ancillary facilities. The area allocated is only about 250 feet by
300 feet. A much larger area is required. [B.21]
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U.S. EPA Response:
Preliminary information from a mobile incinerator supplier indicated that the
space selected was adequate. The actual space needs will be determined after
a mobile incinerator is chosen during the remedial design. Adequate space is
available on site to expand.
Comment: The FS report states "The ash content of the contaminated soil is
assumed to be 70 percent; the water content is assumed to be 20 percent and
the heating value is assumed to be 2,000 Btu per pound." The RI and FS
reports do not present laboratory test data which are commonly used to provide
data for evaluating incineration suitability and characteristics of
incinerator ash. Tests for Btu content, total chlorine content, percent of
ash, and NO are commonly used for evaluating suitability for incineration and
should be determined prior to selecting the remedial alternative. [B,21]
U.S. EPA Response:
Incineration is suitable for materials in the landfill because the
contaminants of concern present in the soils and drums are easily incinerated.
Discussions with vendors of mobile incinerators verified that based on soil
conditions and level of contaminants present in the soils that incineration is
easily implemented. Further tests will be performed as part of the remedial
design to optimize incinerator operation, as discussed in the FS report.
Incineration of soils and liquid is a proven technology.
Comment: The FS report states "the volume of ash remaining is estimated to
be 18,000 to 21,000 cubic yards". This represents 30Z reduction in volume
from the in situ volume. Since the bulk of material to be incinerated is soil
with low organic content it is likely that the volume reduction will be much
less than that presented and in fact may be very small. In addition, the
excavated soil will undergo expansion or "fluff" resulting in a volume
increase relative to in situ volume. If the ash requires treatment prior to
disposal this will further increase the volume. [B.22]
U.S. EPA Response:
The incinerator ash will be disposed back into the excavated area as long as
it is able to be delisted. If the reduction of volume is less than 30Z, there
will still be plenty of space to dispose the ash. The actual volume of
materials in the landfill and soils/ash remaining after incineration can only
be determined after excavation and incineration.
Comment: The FS report states "In addition to the ash remaining after
incineration, residuals from air pollution control would probably consist of
sludge and wastewater requiring treatment if a wet design is used and solid
fly ash if a dry design is used." The issue of disposal of air pollution .
34
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control wastes should be evaluated in much greater detail prior to selection
of a remedial option as this can have significant environmental and cost
impact on an incineration alternative. [B,22]
No test results for total chlorine content of the contaminated material were
presented. This is a critical parameter for evaluation of incineration
alternatives. Since the primary contaminants include chlorinated organics the
air pollution control wastes can be expected to contain significant chloride
content. [B.22]
Treatment of wet scrubber waste water to remove chloride is generally not
feasible and is expensive, resulting in either a concentrated brine or a high
salt content solid both requiring offsite disposal. Similarly, dry scrubber
systems, result in a high salt content solid. Stabilization of such solids
with fly ash is likely to result in significant leaching of chloride to ground
water and surface water. Disposal onsite of wastes from either wet or dry
design air pollution control systems would most likely result in significant
chloride pollution of Conneaut Creek potentially with considerable
environmental damage. Testing of total chlorine content, calculation of
chlorine mass balances for incineration air pollution control systems and
evaluation of associated costs and environmental impact should be undertaken
before selecting a remedial option. [B,22]
U.S. EPA Response:
The use of wet or dry scrubbers will be addressed during the remedial design.
Discussions with vendors of mobil incinerators indicated a preference for dry
scrubbers.
Costs associated with the air pollution Control facilities are included in the
capital costs associated with incineration. The actual costs are dependant on
the incinerator selected.
No tests were run on total chlorine because a representative sample of
materials in the landfill was not able to be obtained. As discussed in the FS
report, prior to final design a test burn will be run.
Comment: With reference to incinerator ash the FS states "if delisting is
not possible, the material would need to be disposed of in a RCRA landfill as
discussed in alternatives E and F." Construction and operation of onsite RCRA
landfill would require long term maintenance. If the waste is successfully
delisted it would still remain a nonhazardous waste. Backfilling of the ash
was not discussed with respect to compliance with State requirements for
landfilling nonhazardous waste. [B,23]
U.S. EPA Response:
The selected remedy assumes that the characterization of the ash will allow
the State of Ohio to waive their solid waste regulation regarding the final
35
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deposition of the ash. The State of Ohio has agreed to consider such a waiver
when analysis of the ash is available.
Excavation
Comment: Mechanical excavation is expected to extend about 30 feet deep for
all source control alternatives except containment. The contaminated material
occurs within 50 feet of a very steep slope leading to Conneaut Creek. No
strength data was presented in the RI/FS reports for the soil. However,
stability of the excavation at such depths is uncertain. An outward failure
with release of contaminated material to Conneaut Creek is a risk which has
not been addressed in the RI/FS reports. Such a failure could result in far
greater risk to public health and the environment than is presented by the
site in its present condition. Strength data for the soil should be obtained
and a geotechnical evaluation of the risk associated with excavation should be
undertaken prior to selection of a remedial alternative. [B,23]
U.S. EPA Response:
Any strength data needed prior to excavation will be generated during the
remedial design. During test pit excavation, the walls were extremely stable.
However, if the southern wall of the landfill is not stable, the slope soils
could easily be removed and stored during excavation and replaced after
excavation is completed.
Comment: The FS report state* "The conditions at the Big D site are
favorable because the depth of drums and the drums are expected to be in
generally good-condition based on the results of the test pit excavation."
The RI report (page 5 of Appendix I) however, states that "Over half the drums
observed were either partially crushed or ruptured." The above conclusion
concerning the excavation of drums is inconsistent with the test pit results
presented in the RI. It should be noted that excavation of the drums would be
expected to result in rupture of many of the drums which may be currently
intact. [B,24]
U.S. EFA Response:
The drums observed during the test pit excavation, which were not ruptured,
were in good physical condition. Excavation of these drums should not result
in rupture. If drums in a less stable condition do rupture during excavation,
the contents of the drum and newly contaminated soils would be collected and
incinerated.
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General
Comment: Instead of undertaking the dye study during the sampling period,
the dye study should have been completed first so that the location of the
stations could be based on the hydrodynamic flow of the creek, rather than the
approach that was used where the dye study revealed that the siting of the
stations may have resulted in the collection of samples in areas not
representative of the flow of the creek. [B,17]
U.S. EPA Response:
The dye study was done prior to collecting samples during the second round.
It would have been better to perform the dye study prior to the first round,
however the data collected is still valid.
Comment: As uptake and absorption are extremely important parameters in the
movement of both inorganic and organic pollutants, and as both pH and organic
carbon content of soil have a major influence on the chemodynamics of the
compounds, these parameters should have been measured in order to better
assess the movement of these compounds in the environment. [B,17]
U.S. EPA Response:
This information would have been useful, however it was not necessary to the
purpose of the RI and FS. The determination of the nature and extent of
contamination and the risks posed to public health and the environment were
not affected by the lack of this data.
Comment: A reference to Table 6-16 in the RI report for the ambient water
quality criteria was made. No such table exists in the report. Rather, the
data was taken from Table 6-9. The source of the AWQC for lead was not
referenced. [B,19]
U.S. EPA Response:
Table 6-9 was the correct reference. The reference for lead is listed on page
6-52 of the RI report.
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SECTION 3: SUMMARY OF OHIO ENVIRONMENTAL PROTECTION AGENCY COMMENTS AND U.S.
EPA RESPONSES
Comment: Alternative 9 requires that delisted ash will be backfilled into
the source material excavation. The delisted ash is considered a solid waste
under Ohio law and ORC 3734-02-G provides a method for the Director of Ohio
EPA to determine if disposal at the Big D site would not pose any adverse
effects to public health or the environment. The ROD should indicate that
OEPA Solid Vaste regulations are ARARs for ash disposal on-site and authority
to exempt any substantive requirements of those regulations rests with the
OEPA. [F,]
U.S. EPA Response:
The ROD identifies all ARARs submitted by the State of Ohio which apply to the
clean-up at the site. The ROD also identifies that a request for a waiver of
Ohio's Solid Waste Regulations has been forwarded to the Ohio EPA.
Comment: The FS report and the proposed plan should have considered the
possibility that the incinerator ash might not meet the substantive
requirements of RCRA delisting. During the remedial design, determination
will be made about the treatability of contaminated source materials. If
incineration does not produce a delistable ash then the ash material will have
to be handled as a hazardous waste. Alternative 7 might be retained or
considered as a backup for this eventuality. [F,]
U.S. EPA Response:
If the ash is not delistable, alternative 7, which entails placing the ash
back in the landfill and vitrifying the ash and contaminated soils, could not
be implemented, either. If the ash is not delistable then the State of Ohio's
Solid Waste Regulations would require it be disposed of as a RCRA hazardous
waste. Vitrification is simply another containment option and will not meet
the Ohio's solid waste ARARs any more than the selected remedy will.
Comment: As noted in section 7.2 of the RI report,and as we discussed in
the past, the extent of off-site migration of ground water contamination can
not be verified without further sampling of ground water. The ROD should
address specific activities that will occur during a pre-design project. What
is the extent of the study that is needed to adequately define the extent of
ground-water contamination. The ROD should include objectives and suggest
methods for determining the complete extent of off-site ground-water
contamination and for characterizing the hydrogeology necessary in order to
design the extraction systems. Any further investigation of the extent of
ground-water contamination should also be designed to address the concerns of
local residents that were presented during the August 8, 1989 public meeting.
Ohio EPA will provide the information that our Division of Groundwater has
obtained about water usage in that area nd any weM sample results that you do
38
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not already have. [F,]
U.S. EPA Response:
This has been added to the Record of Decision.
Comment: In section 3.3 of the FS report, process options for the treatment
of ground water are evaluated based on effluent goals from Table 3.1. The
substantive requirements of the National Pollutant Discharge Elimination
System program as administered by the Ohio EPA Division of Vater Pollution
Control will ultimately determine the choice of treatment methodologies
designed and implemented at this site. While risk based objectives are used
as goals for clean-up of a contaminated site, the concentration limits for a
discharge are set by the NPDES program based on the water quality of the
receiving stream, flow rates, and other factors including implementation of
Best Available Technology. It is likely that detailed treatability studies
and design review will show that process options in addition to GAC will be
required to adequately treat the ground water prior to discharge. [F,]
U.S. EPA Response:
If it is determined that further ground .water treatment is necessary prior to
discharge, it will be implemented, and has been noted in the ROD.
Comment: The ROD should indicate that cleanup goals will be based on
cumulative risks. Though multiple exposure pathways did not pose significant
risks in the RI it is possible that other risks will be documented during pre-
design or later phases of the project. Any final clean-up standards should be
based on risks calculated from cumulative exposure from all possible exposure
routes. [F,]
U.S. EPA Response:
The ROD states that clean-up goals are based on cumulative risks.
BIGRES.TWO/2
9/27/89
39
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APPENDIX A
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f?
/ <. L^ ".j -f/c Jju
10- 12-
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'"If-
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APPENDIX B
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COMMENTS ON THE RI/FS REPORTS
BIG D CAMPGROUND SUFERFUND SITE
tto:
US Eanromnental Protection Agency - Rcgkm 5
Woodward-Clyde Consultants
Consulting Engineers. Geologists, and Environmental Scientists
v ' 2622 O'Neal Lane. Baton Rouge. LA 70896
-------
Glin
CHEMICALS
P.O. BOX 848, LOWER RIVER ROAD. CHARLESTON. TN 37310
(615) 336-4395
VERRILL M. NORWOOD
Vie* Pmidtat
BaviramaMl Attain
August 23, 1989
Ms. Gina Weber
Office of Public Affairs (5PA)
U.S. Environmental Protection Agency
230 South Dearborn Street
Chicago, Illinois 60604
Attention: 5HS-11
Re: Big D Campground Superfund Site
Comments on the RI/FS Reports
Dear Ms. Weber:
Olin Chemicals Corporation retained Woodward-Clyde Consultants to review the
Remedial Investigation and Feasibility Study (RI/FS) report prepared by U.S. EPA -
Region V for the Big D Campground Superfund Site. This report is dated June 1989
and supplied to us under cover of Janice Bartlett of EPA's letter dated July 27, 1989.
There are significant comments on the Remedial Investigation (RI) report and serious
concerns on the validity of the data used, various assumptions that were made and
conclusions arrived at. The Feasibility Study (FS) report is very inadequate in that it
did not evaluate all feasible alternates and for the alternates selected for further
consideration, complete evaluation was not done.
Specific comments referring to individual pages in the RI/FS report prepared by
Woodward-Clyde Consultants are attached hereto. We want to bring to your attention
the following major technical flaws in the RI/FS reports:
o Ground water flow and quality characterization is based on six water elevation
and two sampling temporal data points over a period of only 4 months and is
completely inadequate.
OLIN CO-RFORATION
-------
Ms. Gina Weber
Page 2
August 23, 1989
o Review of the two ground water quality data obtained from the deep wells for
RI/FS strongly suggest that contamination may have been introduced by drilling
during installation of the wells.
o The data do not suppon the conclusion reached regarding a definite northward
movement of ground water flow. The results of the groundwater model and
assumptions made therein are in serious question as a result
o Various assumptions used on the Risk Assessment are highly questionable.
o No sound scientific or technical basis for the estimate on number of drums at
the site has been presented. We do not believe that the number can be
anywhere near 2500 or 5000 as stated in the RI/FS reports.
o We question the design and location of the groundwater recovery trenches and
more importantly the very need for the recovery trenches.
o On source control, some of the recommended alternates have not been fully
evaluated. For example: the geotechnical stability of the very steep slope
leading to Gonneaut Creek • while excavating up to 30 feet is very questionable
and could endanger the creek severely and could pose serious construction
safety problems. Additionally, the pros and cons of on-site incineration were
not studied in sufficient detail. To be specific, on-site incineration could lead
to higher risk to the environment and public health than even a no action
alternate.
o Certain very viable alternates such as in-situ solidification and stabilization were
not considered.
Olin would be most happy to discuss these comments at your earliest convenience.
If you have any questions, please, call me at 615/336-4395.
Very truly yours,
Verrill M. Norwood, Jr.
VMN:lbr
1167
Enclosure
cc: Ms. Janice Bartlett
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Woodward-Clyde Consultants
COMMENTS ON BIG D CAMPGROUND, KINGSVILLE, OHIO
REMEDIAL INVESTIGATION - FEASIBILITY STUDIES (RI/FS)
INTRODUCTION
Detailed below are Woodward-Clyde Consultants' comments on Olin Chemicals' Big
D site at Kingsville, Ohio. These comments have been made following a thorough
review of the following documents:
(i) U.S. EPA - Hazardous Site Control Division
Contract No. 68-01-7251
Final RI Report, Big D Campground, Kingsville, Ohio
June 1989; WA 48-5LB1.1 Volumes I and H
(il) U.S. EPA - Region V (Waste Management Division)
Contract No. 68-W8-0084
Final FS Report, Big D Campground, Kingsville, Ohio - June 1989;
WA 01-5LB1
COMMENTS ON THE REMEDIAL INVESTIGATION REPORT:
Remedial Investigation
Page ES-4: The Executive Summary of the RI states that "Organic
Compounds were detected in samples from most deep wells at
low but significant concentrations. The contamination is
probably the result of vertical migration of contaminants
through the hard grey clay unit at localized areas or possibly
the result of past site activities."
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The chemical data presented in the RI for ground water from
the confined bedrock aquifer raises serious concerns with
respect to the validity of the RI data:
1. Validity of the ground water samples and analyses from
the deep wells (those screened in the unit designated
the confined bedrock aquifer) is questionable.
2. Significance of the low, inconsistent concentrations
detected in the deep aquifer is doubtful.
3. Temporal patterns in the data suggest that the
concentrations in ground water from the deep wells may
result from residual contamination introduced to this
depth by drilling for installation of the monitor wells.
4. Well development was not sufficiently defined and may
not have been properly done.
The organic compounds detected (see attached Table 1) in the
deep wells are primarily acetone, methylene chloride and
chlorobenzene. As noted in Section 4.3.3 of the RI, acetone,
methylene chloride, chlorobenzene, and toluene (also detected
in some of the deep well samples) and trichlorethylene were
detected in some field and/or laboratory blanks up to 305.8 ppb
of total VGA's. Acetone was used as a rinse in
decontamination of ground water sampling equipment. This is
especially troubling since acetone is the compound reported in
the highest concentrations and with the greatest frequency in
the deep wells.
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As stated in Section 4333 "Acetone, a common field and
laboratory contaminant was the only compound detected during
both sample rounds in a single deep well." If acetone is not
included, the detected total VOA concentrations in the deep
wells exceed 10 ppb only in one sample (34.2 ppb in the first
sample from Well 4D). The latest measurement from Well 4D
was 0 ppb.
All of the wells were sampled and analyzed on two or three
dates. This spanned a period of 4 months and is insufficient
to make ground water quality conclusions. The data for
repeated samples from any single deep well are inconsistent.For
example, subsequent samples resulted in the following total
VOA concentrations.
o well 1DO to 76 ppb
o well 2D 1,100 to 118 to 0 ppb
o well 3D628.6 to 48 to 0 ppb
o well 4D 71.2 to 900 to 0 PPB
"o well 5D 5,922 to 0 ppb
o well 6D430 to 38 ppb
In addition, dedicated sampling equipment should have been
used to avoid problems of .equipment contamination during
sampling. Because of the presence in the blank samples of the
same contaminants reported to be present in the samples and
the inconsistent results from repeated samplings, the ground
water sample and analysis results do not indicate significant
concentrations of organics in the deep ground water. Note in
the last sampling event, four of the six wells did not report any
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detectable VOAs. Even if the sampling and analysis results
were not of questionable validity the data would not necessarily
demonstrate contamination of the confined bedrock aquifer.
The data for total VOAs listed above illustrate a general trend
of decreasing concentration with succeeding samplings. This
suggests that the detected organic compounds could be the
result of contamination from shallower zones that was carried
into the deeper aquifer during drilling for installation of the
deep monitor wells. Repeated purging and sampling of a well
would gradually reduce the constituent concentrations resulting
in lower detected concentrations with repeated samplings and
perhaps invalidate the conclusion that no deep contamination
exists.
The data in Appendix C (see Volume n of the Final RI report),
does not indicate the volume of water that was removed from
each well during development and during purging for each
sampling event. This information is necessary to evaluate the
validity of the ground water samples.
APP.A. (See Volume II of Final Remedial Investigation Report)
P. 15 Boreholes 2D, 3D and 4D were advanced 10 to 20 feet deeper
than the planned well depth. On attempting to plug the bottom
of these boring cement bentonite grout rose in the borehole
through the screened interval, Borehole 2D was apparently
properly plugged and abandoned and the well was installed in
a new borehole adjacent to the first location. Borehole 3-D,
however, was drilled out using a core barrel. Borehole 4-D was
flushed with water to remove the rout. The adequacy of the
measures for wells 3-D and 4-D is questionable and residual
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grout in the wells may impact quality of water samples from
these wells. The procedure used for the borehole 2-D should
also have been used for 3-D and 4-D.
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TABLE 1
ORGANIC COMPOUNDS DETECTED IN DEEP WELLS
Concentrations in Parts Per Billion (ppb)
Volatiles
Chlorobenzene
Methylene Chloride
Tetrachloroethene
Toluene
Acetone
2-Butanone
Benzene
Total Vols
Acid Ext.
Phenol
Well ID
1st 2nd
74
2J
0 76
Well 2D
1st 2nd 3rd
8
1100 110
1100 118 0
Well 3D
1st 2nd 3rd
Well 4D
1st 2nd 3rd
WellSD
1st 2nd
2J
5.4
1.2J
620 48
2.2J
11
26 900
32
82J
110J
30J
5700
628.6 48 0 71.2 900 0 5922 0
2.4J
Well 6D
1st 2nd
430 38
430 38
Total Acid Ext.
0 0
000
0 0 0 2.4 0 0
0 0
0 0
J = Estimated value. Used when estimating a concentration for tentatively identified compounds where a 1:1
response factor is assumed or when the mass1 spectral data indicates the presence of a compound that
meets the identification criteria and the result is less than the specified detection limit, but greater than
zero.
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Page 6
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TABLE 1 CONTINUED
ORGANIC COMPOUNDS DETECTED IN DEEP WELLS
Concentrations in Parts Per Billion (ppb)
Sampling
Well ID
1st 2nd
Well 2D
1st 2nd 3rd
Well 3D
1st 2nd 3rd
Well 4D Well 5D Well 6D
1st 2nd 3rd 1st 2nd 1st 2nd
Base/Neut. Ext.
Isophorone
Bis (2-ethylhexyl)
phthlate
Diethylphthalate
Total B/N ext
2.7J
2.7 0
5J
0 0
4J
3J
3J
0 04 0 03
0
0 0
J = Estimated value. Used when estimating a concentration for tentatively
identified compounds where a 1:1 response factor is assumed or when
the mass spectral data indicates the presence of a compound that meets
the identification criteria and the result is less than the specified
detection limit, but greater than zero.
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Page 3-7: (a) Northward movement of the shallow ground water is stated as fact.
This is not documented and is not justified by the data in the RI. Table
3-1 (p. 3-16) shows some higher ground water elevations north of wells
IS, 5S and 4S. For example, water levels in 3S, the northern most
monitor well, and RW3 (a residential well located about 600 feet north
of the reported ground water divide at the site) were 712.90 feet and
719.83 feet, respectively, on September 26, 1987 and higher than the
wells immediately to the south. In fact, the ground water elevation was
higher in the northernmost shallow monitor well, MW-3S, than in wells
to the south of it on four of the six dates on which ground water
elevation measurements were reported. Ground water elevation in
RW3 was 720.07 feet msl on May 16, 1987, higher than monitor wells
located to the south. Furthermore, it is difficult to predict a contour
of 714 feet as shown in Figure 3-3 (p. 3-8) with the existing ground
water elevation data. This contour was drawn considerably north of
well 3S, the northern most monitor well and the northern most data
point. Also, the water level around the 712 feet contour line in Figure
3-4 (p.3-9) can be interpreted in other ways. For instance, an east-
west trough could exist instead of a closed depression. In addition, the
data presented in the RI is not adequate to verify that the shallow
aquifer is continuous to the north of the site. Additional measuring
points are necessary to define the direction of the ground water
movement from the site.
- (b) Paragraph 1 states that since the unusually low water table elevations
in the fall do not represent normal site conditions, ground water flow
systems have been discussed using May 1987 data. If this is the case,
ground water flow to the north would be primarily uni-directional as
indicated by Figure 3-3. This is contradictory to the two-lobed
contaminant plume used in the analytical model and depicted in Figure
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4-6 (p.4-19). The pattern of a two-lobed plume could be simulated
under the initial condition of a two-directional ground water flow as
depicted in Figure 3-4 (p3-9). With the available data, the conclusions
arrived at on p. 3-7 and p. 4-18 regarding the northward movement and
the two-lobed plume are not substantiated. It should be noted that
seasonal fluctuations in ground water elevation occur even in normal
precipitation years and the measurements during the RI may reflect
normal trends although the acutal elevations would vary from year to
year. It is possible that the northern portion of the site exhibits a
seasonal reversal of flow direction.
Page 4-12: The RI states that well RW-3 "is probably not screened in the same water
bearing unit as the monitoring wells at the Big D site. Well construction,
recharge rates, and static water level indicate this well receives water from a
localized perched water table zone." The basis for this conclusion is not
documented in the RI." The data presented in the RI (Table 1 of Appendix C)
does not distinguish the aquifer at RW-3 from that at RW-1, RW-2, RW-4 and
the onsite monitor wells completed in the water table. Table 1 of Appendix C
(see Volume II of Final RI Report) lists RW-3, RW-1, RW-2 and RW-4 as
screened in the overburden (assumed based on discussions with owners). No
hydrogeologic analysis or other data is presented to indicate that RW-3 is not
screened in the same aquifer as the other residential wells or the shallow onsite
monitor wells. The ground water elevation in RW-3 is higher than in the
northern most shallow onsite monitor wells and this may reflect a ground water
elevation surface for the water table different from that assumed in the RI
rather than necessarily indicating a different aquifer. It should be noted that
the RI also indicates that the water table aquifer onsite is a perched aquifer in
the over burden.
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p. 4-18: (a) One of the stated reasons for the two-lobed contaminant plume is
surface water recharge from the drainage swale at the northern end of
the site. If the drainage swale is a significant source of recharge, the
local ground water flow would be expected to be southward from the
south side of the swale and northward from the north side of the swale
(i.e. a ground water divide). This is contradictory to the RI's stated
northward direction of the ground water movement
(b) Residential well RW2, located at 3700 Creek Road, does not show any
chlorobenzene contamination or other contamination believed to come
from the site. However, Figure 4-6 shows that the computer simulation
predicts that there is about 3mg/l of chlorobenzene in the vicinity of
RW2. The detection limit for chlorobenzene is .005mg/l. The accuracy
of the transport model is implied in the RI to be about one order of
magnitude, but in this case is in error by at least a factor of 600. The
assumptions on which the model is based may not be valid. -
p. 4-5 Two background soil samples were collected, both from the same
location. The RI then states that "As shown in Table 4-1 the highest
borehole concentrations for all compounds except silver exceeded the
concentrations detected in the two background samples. The highest
concentrations of each inorganic compound detected in the test pits
exceeded the concentrations in both background samples with the
exception of antimony, arsenic, beryllium, cobalt, iron, cyanide,
selenium, thallium and vanadium." These are true statements, however,
it should be noted that this does not necessarily indicate elevated
concentrations in the soil borings and test pits relative to the two
background samples. Most of the inorganic constituents analyzed are
present in varying concentrations in soil samples as a result of natural
processes. The naturally occurring concentrations will vary from
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location to location and will exhibit a statistically distributed range of
values which is dependent on the number of samples of the total
population of samples which have been analyzed. That is, if the range
for a very small number of samples is compared to the highest value
observed from a much greater number of samples collected from the
same population, it is expected that some values will exceed the range
of the small number of samples. Since many more samples were
analyzed from boreholes and test pits than from background locations,
it should be expected that some values will exceed the range exhibited
by the background samples. Note that the lowest concentrations of
the borehole and test pit samples for the inorganic constituents are also
lower than or equal to (for not detected) the lowest values for the two
background samples.
The comparisons used and conclusions reached are statistically invalid.
p. 4-20:
Soil gas concentration contours have not been provided to help evaluate
the validity of the estimated extent of the ground water contamination
plume, as shown in Figure 4-6 (p. 4-19). Further verification of the
results is necessary.
Appendix H: (1)
(see Volume II of
Final RI Report)
In the modeling of the plume, it has been assumed that the
(water table aquifer is infinite in extent. This assumption
is contradictory to the actual physical characteristics. In fact, data were
not presented that verify that the aquifer is continuous in the area
included in the model. Also the model did not account for the vertical
recharge from the surface.
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(2) The Princeton Model is limited to modeling a single source with a single
ground water flow direction. The study used a combination of results
from multiple model runs as a weighted average of concentration with
respect to discharges from the two source areas. Theoretically, since
it is not based on solute mass balance or mass conservation, the
weighted average concentration may deviate remarkably from the true
value at each location. It is, therefore, essential to verify the results by
running other models (analytical or numerical) and comparing the
results. No indication of model verification was submitted.
In light of the above, we suggest that the following be further
considered:
1. Obtain water level data for additional dates and provide more
data points further north.
2. Utilize another analytical model to verify the Princeton Model's
results with the same given assumptions;
3. After adequate data is obtained, refine the assumptions and use
other analytical or numerical models to obtain results based on
more realistic physical conditions. A numerical model or a
combination of analytical and numerical models is highly
recommended since it can better simulate the subsurface
conditions at the Big D site;
4. Sensitivity analysis of the responses of ground water flow and
contaminant transport with respect to changes in the
hydrogeological parameters is essential since the input values
are based on assumed values and may differ very significantly
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from the actual conditions. No sensitivity analysis is reported
in the RI.
General comment on estimated extent of shallow ground water contamination.
The estimated extent of shallow ground water contamination to the north of the
site is based solely on the predictions from the analytical model and actual
ground water data are limited to the southern edge of the area modeled.
Contradictions exist between the model and the available data and numerous
unverified assumptions are present in the analytical model and the estimation
of contaminant extent. Evaluation of the extent of contamination requires
collection of actual hydrogeologic and water chemical data within the area
modeled. The actual extent may vary significantly from what has been predicted
in the RI, as is indicated by the available data for residential wells.
Table 1 of
Appendix H
(See Volume II of
Final RI Report
Table 1 lists the ground water velocity used in the model as
3.64 x 105cm/sec. This is equivalent to about 1,030,000 feet per
day. Presumably this is a typographical error. What ground water
velocity was used?
Tables 6-2b, 6-3b,
6-4b,6-5b, 6-6b,
6-7b, 6-8b:
The upperbound excess lifetime cancer risk value mathematically should
be reported with three significant digits to obtain more uniform
calculation results.
Selection of soil ingestion rates - The soil ingestion values presented in
the EPA Superfund Exposure Assessment Manual (SEAM) p. 168,
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Table A-5 are presented by age group and are more accurate. The
information in this reference also provides time periods for various
ingestion rates making the assumption of years of soil ingestion
unnecessary.
p. 6-6: Direct contact with contaminated soils/Extent of exposure ...this
scenario assumes that future direct contact with soils will involve soil
up to 8 feet below the ground surface. The basis of this assumption
(depth of 8 feet rather than surface soil) needs to be presented. Use
of surface soil would probably result in significantly lower exposure.
The exposure via this pathway is zero.
p. 6-8: The potential dermal exposure is estimated to be 1 mg soil/cm2 body
area. This estimate is high, a value of 0.6 mg soil/cm2 body area is
more accurate (Lepow, 1975). The value of 1 mg soil/cm2
overestimates the health risk and this should be stated. The Superfund
Public Health Evaluation Manual (SPHEM) states that the uncertainties
of each assumption made during the risk evaluation process and the
resulting over or underestimation of health risk must be clarified.
Evaluation of the impacts of assumptions was not made for any
exposure assumptions.1
The basis for the selection and use of an additional carcinogenic
potency factor for calculating dermal exposures was not stated. The
impact of the use of these factors in addition to the use of factors
developed for ingestion of contaminants on the overall risk estimate was
not discussed.
1Lepow, M.L, et al. Envir.Res., 1Q 415-426 (1978).
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P 5.41; I* is stated that the sampling results for the residential wells did not
reveal any inorganic or organic contaminants that could be attributed
to releases from the Big D site. It should have been stated that for
incomplete exposure pathways there is no actual risk. (See Reference
SPHEM, Page 36, first column, second paragraph). There is no
potential risk associated with the site ground water at this time due to
an incomplete exposure pathway. Risk is overestimated because it is
assumed that the pathway is complete at this point. The potential for
future risk exists only if a production well is placed in a location
completing the exposure pathway.
It should also be noted that in comparing production well contaminant
concentrations with site monitoring well concentrations in the same
aquifer, that lower concentrations may occur in dynamic systems such
as production wells in comparison to stagnant systems such as
monitoring wells. The use of monitoring well data applied to
production well consumption may overstate the health risk.
p. 6-12: When referring to risk, it should be clarified that the future is based on
a period of 70 years for risk assessment purposes, not an infinite time
period. It is stated that both acute and chronic exposures for the
potential ingestion of ground water were evaluated. Only chronic
hazard index values can be found on the RI.
For infrequently found contaminants, geometric mean concentrations
were not calculated and the contaminant was not evaluated under
probable case conditions. In order to evaluate these contaminants
under probable case conditions, the geometric mean can be calculated
utilizing a concentration equivalent to one-half the detection limit for
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that specific contaminant when there are "non-detectable" levels. This
approach more accurately estimates the actual or probable exposure.
p. 6-8, 3rd
Paragraph
It is stated that extrapolations from animal studies do not address
human-animal differences in absorption. This is not true - all effect
levels obtained from chronic animal studies are multiplied by a safety
factor of 10 to account for interspecies variation.
It is also stated that the ACI and CPF calculations assume that the
human body absorbs 100% of the contaminant, the same extent as an
experimental animal. For most compounds this is not true.
The reasons for excluding the percent contaminant absorbed in
equations 6-1 and 6-2 are not satisfactory. However, by assuming 100%
is absorbed, the estimated dose is higher and the calculated risks are
more conservative. Also, it was stated elsewhere that 1% inorganic and
5% organic dermal exposure assumptions would be used. These
percentages are used in eq. 6-1 and 6-2 in Appendix H.
p. 6-15
The BCF values quoted for chlorobenzene range from 10 to 4185. A
value of 465 was selected and the basis for this selection is not stated.
A more conservative approach would be to use the highest value.
Recalculations using BCF of 4185 gives a HI of 032 which is still in the
acceptable range.
Extent of exposure - Estimated doses and HI should have been
calculated for barium, lead and beryllium.
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• p. 6-28 The estimated dose for chlorobenzene is 9.5 E -01 not 9.21 E 01 Mg/kg.
(See page 6-16) The HI is 3 .5 E-02 not 3.4 x E-02.
Appendix exposure dose = 10,230 mg/kg should be 10230 mg/kg or 10,230
H-5
p. 4-26
Location of sampling stations based on flow of dye
Instead of undertaking the dye study during the sampling period, the
dye study should have been completed first so that the location of the
stations could be based on the hydrodynamic flow of the creek, rather
than the approach that was used where the dye study was performed
after the stations had been sited. The dye study revealed that the siting
of the stations may have resulted in the collection of samples in areas
not representative of the flow of the creek.
p. 5-3
Measurement and documentation of pH in the soils and water samples.
As uptake and absorption are extremely important parameters in the
movement of both inorganic and organic pollutants, and as both pH and
organic carbon content of the soil have a major influence on the
chemodynamics of the compounds, these parameters should have been
measured in order to better assess the movement of these compounds
in the environment.
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p. 6-8
Average body surface of child.
p. 6-32
Uncertainties.
p. 6-37 to 6-60
Calculations
A discrepancy exists in the average body surface area of a child used
in the risk assessment Although EPA (1985) stated that the average
surface is 1200 cm2, the 1988 Superfund Assessment Manual (Page 127)
quotes that the dermal area of a child is 9400 cm2.
The derivations and calculations of the carcinogenic potency factors and
noncarcinogenic acceptable daily intake values should be discussed in
more detail. In addition a discussion of the safety factors included in
the calculations should be included. This information is necessary to
determine the validity of the conclusions.
Two of the ADI values i.e. those for barium and beryllium which were
used in the study differed from the values quoted in the 1986 EPA
Exposure Manual. If some other source was used, it should be
referenced. In the case of barium, the value differed by 11% but in the
case of beryllium, the figure used, 5.00E-03, was one order of magnitude
less sensitive than the value of 5.00E-04 quoted in the 1986 EPA
manual. In the text it was inferred that a 1987 revision of the Toxicity
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data was the source of some of the ADI values. A full reference to this
manual was not made as a footnote to the appropriate tables.
p. 6-57
Source of ambient water quality criteria.
A reference to Table 6-16 for the ambient water quality criteria was
made. No such table exists in the report Rather the data was taken
from Table 6-9. The source of the AWQC for lead was not referenced.
Geophysics
(1) On page'4-3 of the RI report (Vol.I) landfill volumes are
"estimated from the geophysical survey to be 35,000-52,000 cubic
yards." There is no discussion upon which that statement is
based. Later, on the same page, is the statement "based on the
results of the test pit excavation the estimated volume of
contaminated fill is 25,000 to 35,000 cubic yards." Were the fill
estimates actually made from conversations with the transporter,
from the geophysics, or from the test pits? It is not clear. The
actual calculations and assumptions used should be presented.
(2) On page 7-1 of the Summary of Conclusions of the RI report
(Vol.I), the statement is made "Based on the geophysical survey
and the test pit excavation results, it is estimated that there are
two source areas with a combined volume of 25,000 to 35,000
cubic yards." Again, supporting documentation for this
conclusion was not found.
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(3) In the FS report, several references to the RI report are made
(pp. ES-3,1-31, 2-5, etc.) stating "that 2^00-5,000 drums may
be buried within the suspected drum boundary" inferred from
the aforementioned fill volumes. No documentation correlating
either the geophysical results to the fill volumes, or the
geophysical results to a total number of buried drums was
presented in the RI or FS reports. Again, the calculations and
assumptions used to obtain this estimate should be provided.
Also, the geophysical survey detects metal pieces, rods, etc.,
which might be present in the soil. These might influence the
results to a great extent and might have erroneously been
interpreted as indicating the presence of drums. The repjort
makes no mention of such possible errors.
Comments On Feasibility Study (FS^ Report
Table ES-1 Table ES-1 indicates that alternative 6, source area containment,
treatment of ground water outside contaminated area, complies with all
ARARS and is protective for soils and ground water. It also indicates
that it is easily implemented with proven technologies. Table ES^l
indicates that alternatives 2 and 6 have minimal risk during remediation,
alternatives 4 and 8 have moderate risk and alternatives 3, 5, 7, and 9
have high risk. Alternative 6 also is indicated as requiring relatively
short time to implement. Of the alternatives developed in the FS,
Alternative 6 appears to have distinct advantages during the remediation
when the risk for release to the air of relatively high concentrations of
contaminants is much lower than for other alternatives. The only
disadvantage listed for Alternative 6 relative to some other alternatives
is that the long term risk (presumably of release of slow moving
contaminants to ground water) is expected to be higher. Such releases
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can be detected by monitoring and since the ground water moves very
slowly, allows considerable time for corrective measures before human
exposure would occur. The short term risk of exposure to relatively
high concentrations from fast moving air releases during alternatives
requiring extensive excavation allows little time for response and
appears to represent the greater risk to human health.
2-23 to 2-36,
3-35 to 3-37 Onsite incineration will require a high volume flow of water for
operation. The discussion of incineration does not identify the source
or discuss the availability of this water and the associated cost. Ready
availability of this volume of water is questioned since discussion of a
soil bentonite slurry wall barrier on page 3-55 indicates that water for
construction of the slurry wall would have to be obtained from an
unspecified offsite location. Availability of the larger volume of water
«
for onsite incineration is thus questionable.
Figs. 3-7,3-8
and 3-9 The area allocated for incineration in each onsite incineration option
as illustrated on the referenced figures appears to be substantially less
than that required by available transportable incinerators with the
required ancillary facilities. The area allocated is only about 250 feet
by 300 feet. A much larger area .is required.
P 3-37 The FS states The ash content of the contaminated soil is assumed to
be 70 percent; the water content is assumed to be 20 percent and the
heating value is assumed to be 2,000 Btu per pound." The RI and FS
do not present laboratory test data which are commonly used to provide
data for evaluating incineration suitability and characteristics of
incinerator ash. Tests for Btu content, total chlorine content, percent
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ash, and NOX are commonly used for evaluating suitability for
incineration and should be determined prior to selecting the remedial
alternative.
p. 3.37 The FS states "the volume of ash remaining is estimated to be 18,000
to 21,000 cubic yards". This represents a 30% reduction in volume from
the in situ volume. Since the bulk of the material to be incinerated is
soil with low organic content it is likely that the volume reduction will
be much less than that presented and in fact may be very small. In
addition, the excavated soil will undergo expansion or "fluff resulting
in a volume increase relative to in situ volume. If the ash requires
treatment prior to disposal this will further increase the volume.
p. 3-37 The FS states "In addition to the ash remaining after incineration,
residuals from air pollution control would probably consist of sludge and
wastewater requiring treatment if a wet design is used and solid fly ash
if a dry design is used." The issue of disposal of air pollution control
wastes should be evaluated in much greater detail prior to selection of
a remedial option as this can have significant environmental and cost
impact on an incineration alternative. No test results for total chlorine
content of the contaminated material were presented. This is a critical
parameter for evaluation of incineration alternatives. Since the primary
contaminants include chlorinated organics the air pollution control
wastes can be expected to contain significant chloride content.
Treatment of wet scrubber waste water to remove chloride is generally
not feasible and is expensive, resulting in either a concentrated brine
or a high salt content solid both requiring offsite disposal. Similarly,
dry scrubber systems, result in a high salt content solid. Stabilization
of such solids with fly ash is likely to result in significant leaching of
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chloride to ground water and surface water. Disposal onsite of wastes
from either wet or dry design air pollution control systems would most
likely result in significant chloride pollution of Conneaut Creek
potentially with considerable environmental damage. Testing of total
chlorine content, calculation of chlorine mass balances for incineration
air pollution control systems and evaluation of associated costs and
environmental impact should be undertaken before selecting a remedial
option.
p 3.35 With reference to incinerator ash the FS states "if delisting is not
possible, the material would need to be disposed of in a RCRA landfill
as discussed in alternatives E and F." Construction and operation of
an onsite RCRA landfill would require long term maintenance. If the
waste is successfully delisted it would still remain a nonhazardous waste.
Backfilling of the ash was not discussed with respect to compliance with
State requirements for landfilling nonhazardous waste.
p. 2-29 and 2-30 Mechanical excavation is expected to extend about 30 feet deep for all
source control alternatives except containment. The contaminated
material occurs within 50 feet of a very steep slope leading to Conneaut
Creek. No strength data was presented in the RI/FS for the soil.
However, stability of the excavation at such depths is uncertain. An
outward failure with release of contaminated material to Conneaut
Creek is a risk which has not been addressed in the RI/FS. Such a
failure could result in far greater risk to public health and the
environment than is presented by the site in its present condition.
Strength data for the soil should be obtained and a geotechnical
evaluation of the risk associated with excavation should be undertaken
prior to selection of a remedial alternative.
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•
p 2-30 The FS states " The conditions at the Big D site are favorable because
the depth of drums and the drums are expected to be in generally good
condition based on the results of the test pit excavation." The RI, page
5 of Appendix I, however, states that "Over half the drums observed
were either partially crushed or ruptured." The above conclusion
concerning the excavation of drums is inconsistent with the test pit
results presented in the RI. It should be noted that excavation of the
drums would be expected to result in rupture of many of the drums
which may be currently intact
p. 2-28 and
Figure 2-1 During screening of remedial technologies all solidification/stabilization
techniques except in situ vitrification were eliminated. It appears that
one technology was not considered and that other technologies were
eliminated without adequate test data. The technology now exists to
use large diameter augers through which a stabilization fixation slurry
is pumped. The auger mixes the slurry with the waste material and
contaminated soils, drums would be ruptured and the contents fixed
within the slurry. This technology is not subject to the same limitations
as the other solidification/stabilization technologies listed on Figure 2-
1. In addition, other stabilization techniques were eliminated based on
questions of effectiveness and possible leaching. Bench scale tests
should have been completed prior to elimination to determine if
effective treatment mixes are available.
In addition, excavation and offsite incineration of intact drums combined
with stabilization of the soil and ruptured drums should be considered.
It does not appear that these alternatives were considered.
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Neither the description of each alternative nor the cost estimate table
for each alternative present adequate detail to determine if all essential
elements of the alternative have been considered and to determine if
the cost estimates are consistent and accurate.
p. 1-47:
Risks were evaluated on future site use (residential scenario). The risk
associated with present use needs to be discussed.
Table Mia,
and M6a:
The procedure to calculate the exposure dose is different - the intake
factors defined below are not the same. Why are these values different?
Intake factor = exposure dose
maximum concentration
Water ingestion
and soil
ingestion
tables
p. 1-42:
Calculations for worst and probable case conditions for soil ingestion
utilized maximum and mean concentrations as well as frequency of
exposure. Calculations for worst and probable case conditions for water
ingestion utilized maximum and mean concentrations and frequency of
exposure was excluded. The use or non-use of a frequency factor
requires explanation.
It is stated that the environmental exposure considered the most likely
to occur is the ingestion of aquatic life that inhabits Conneaut Creek.
No rationale was presented to support this statement, nor was the risk
for this exposure route calculated. Please explain.
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The rationale for including the factor frequency of contact (days') in the
exposure dose equation 365 days
(6-1) is not clear. Frequency of exposure is not generally considered
in calculating a hazard index.
p 1.45 Table 1-10 WQC for the consumption of aquatic organisms only -The
reference for these values was not given.
The WQC for chlorobenzene taken from a 1980 EPA reference is 7.2E-
04 and 7.4E-04. The EPA manual gives a value of 488 • same units.
The WQC for chlorobenzene was quoted as 7.2E-04 /ig/L for
consumption of drinking water and aquatic organisms and 7.4E-04
Mg/L for the consumption of aquatic organisms only from a 1980 EPA
reference. A more recent reference, EPA SPHEM, 1986, gives WQC
value of 488 Mg/L for chlorobenzene for both consumption of aquatic
organisms and drinking water and for the consumption of drinking water
only.
p. 1-49 The worst case soil ingestion of IxlO"3 was selected. Is the basis for
selecting this value valid? See page 6-5
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APPENDIX C
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OhfeEFft
State of OMo Environmental Protection Agency
Northeast District Office
PI 10 E Aurora Road
Twinsburg, Ohio 44087 Celeste
(216)425-9171 Governor
August 25. 1989
Janice Bartlett
Project Coordinator
USEPA Region 5
230 South Dearborn Street
Chicago, Illinois 60604
Dear Ms. Bartlett:
The Ohio EPA would like the Record of Decision for the Big D Campground
Superfund Site to address the following comments. Our comments are intended to
address a few outstanding concerns about the implementation of the proposed
plan that have not been included in the administrative record. Alternative 9
should provide a remedy that is protective of human health and the environment
if these concerns are addressed during or prior to the Remedial Design.
The four main comments below address our concerns about Solid waste issues,
alternatives to delisting of incinerator ash, groundwater investigations and
groundwater treatability. The fifth comment addresses risk objectives for the
project.
1. Alternative 9 requires that delisted ash will be backfilled into the source
material excavation. The delisted ash is considered a solid waste under Ohio
law and ORC 3734-02-G provides a method for the Director of OEPA to determine
if disposal at the Big D site would not pose any adverse effects to public
health or the environment. The Record of Decision should indicate that OEPA
Solid Waste regulations are ARARs for ash disposal on-site and authority to
exempt any substantive requirements of those regulations rests with the OEPA.
2. The PS and the proposed plan should have considered the possibility that the
incinerator ash might not meet the substantive requirements of RCRA delisting.
During the RD determinations will be made about the treatability of
contaminated source materials. If incineration does not produce a delistable
ash then the ash material will have to be handled as a hazardous waste.
Alternative 7 might be retained or considered as a backup for this eventuality.
3. As noted in section 7.2 of the RI and as we have discussed in the past the
extent of off-site migration of groundwater contamination can not be verified
without further sampling of groundwater. The Record of Decision should address
specific activities that will occur during a pre-design project. What is the
extent of the study that is needed to adequately define the extent of
groundwater contamination. The ROD should include objectives and suggest
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Page Number 2 Ohio EPA
August 25, 1989 NEDO
Janice Bartlett
methods for determining the complete extent of off-site groundwater
contamination and for characterizing the hydrogeology necessary in order to
design the extraction systems. Any further investigation of the extent of
groundwater contamination should also be designed to address the concerns of
local residents that were presented during the August 8. 1989 public meeting.
OEPA will provide the information that our Division of Groundwater has obtained
about water usage in that area and any well sample results that you do not
already have.
4. In the section 3.3 of the PS process options for the treatment of
groundwater are evaluated based on effluent goals from Table 3.1. The
substantive requirements of the National Pollutant Discharge Elimination System
program as administered by the OEPA Division of Water Pollution Control will
ultimately determine the choice of treatment methodologies designed and
implemented at this site. While risk based objectives are used as goals for
cleanup of a contaminated site, the concentration limits for a discharge are
set by the NPDES program based on the water quality of the receiving stream,
flow rates, and other factors including implementation of Best Available
Technology. It is likely that detailed treatability-studies and design review
will show that process options in addition to GAC will be required to
adequately treat the groundwater prior to discharge.
5. The ROD should indicate that cleanup goals will be based' on cumulative
risks. Though multiple exposure pathways did not pose significant risks in the
RI it is possible that other risks will be documented during pre-design or
later phases of the project. Any final cleanup standards should be based on
risks calculated .from cumulative exposure from all possible exposure routes.
If you have any question about these comments do not hesitate to contact us.
Sincerely,
Daniel V. Markowitz Ph.D. . '"
Environmental Scientist <-'
Division of Emergency and Remedial Response
c.c. Fran Kovac, Legal
Rod BealsT-NEDO DERR
Kathy DavidsonT^Cl ___
Jennifer Tiell, CO DERR
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