EPA Superfund
Record of Decision:
PB97-964108
EPA./541/R-97/099
January 1998
South Point Plant Site
South Point, OH
9/26/1997
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DECLARATION FOR THE RECORD OF DECISION
SITE NAME AND LOCATION
South Point Plant Site, South Point, Lawrence County, Ohio
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for the South Point Plant Site
(Plant) located in Perry Township in the Village of South Point, Lawrence County, Ohio, which
was chosen in accordance with the Comprehensive Environmental Response, Compensation and
Liability Act of 1980 (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act of 1986 (SARA) and is consistent with the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP) to the extent practicable. This decision is based
upon the contents of the Administrative Record for the site.
The State of Ohio has indicated a willingness to concur with this decision. A written
confirmation is expected, and will be added to the administrative record upon receipt.
ASSESSMENT OF THE SELECTED REMEDY
Actual or threatened releases of hazardous substances from the 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.
DESCRIPTION OF THE SELECTED REMEDY
United States Environmental Protection Agency (U.S. EPA) has selected a remedy that is
intended to be the final action for the Plant. The remedy was presented in the Proposed Plan as
Remedial Alternative RA-5A. The following is a summary of the selected remedj
Active Area
Institutional control
Excavation:
Mid-Plant Area and Coke-Oven Gas Slowdown Areas
Disposal:
On-site consolidation in Eastern Disposal Area - Mid-Plant Area
Off-site disposal - Mid Plant Area and Coke Oven Gas Blowdown Area
Inactive area
Institutional controls
Containment:
Consolidation and placement cf a Single barrier cover - Disposal Area D
Single barrier cover - Eastern Disposal Area
Surface controls - Northern Fly Ash Ponds
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II
Ground Water
Institutional controls
Containment:
Existing pumping containment system
Discharge:
Ohio River
Estimated Cost - $3,910,800
Also, as part of RA-5A, some additional characterization will be required in the area of the
former melamine ponds during the remedial design. The extent of this additional data collection
will be determined during the remedial design planning phase.
DECLARATION STATEMENT
The selected remedy is protective of human health and the environment, complies with Federal
and State requirements that are legally applicable or relevant and appropriate to the remedial
action, and is cost-effective. This remedy utilizes permanent solutions and alternative treatment
technologies to the maximum extent practicable for the site. If soils from the Coke-Oven Gas
Slowdown Area or potential hot-spots identified in the Mid-Plant Area fail the Toxicity
Characteristic Leaching Procedure (TCLP) and need to be treated prior to off-site disposal, then
the statutory preference for treatment as a principal element of the remedy would be achieved.
However, if the excavated soils do not need to be treated and because treatment of the additional
principal threats at the site was not found to be practicable, this remedy would not satisfy the
statutory preference for treatment as a principal element of the remedy.
Because hazardous substances will remain at the site, U.S. EPA will conduct a five-year review
in accordance with Section 121 of CERCLA to assess whether; y other response is necessary.
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DATE William E. Muno
Supcrfund Division Director
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U.S. EPA Superfund
Record of Decision
South Point Plant Site
South Point, Lawrence County, Ohio
September 1997
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TABLE OF CONTENTS
I. Site Description
II. Site History and Enforcement Activities
1
III Highlights of Community Participation 3
IV. Scope and Role of Response Action 4
V. Site Characteristics 5
VI. Summary of Site Risks 8
VII. Description of Remedial Alternatives 11
VIII. Evaluation of Alternatives 16
IX. Statutory Determinations 25
X. Explanation of Significant Differences 26
XI. State Concurrence 26
FIGURES
Figure 1 Site Location Map
Figure 2 Site Base Map
TABLES
Table 1 Evaluation Table
Table 2 South Point PRGs
APPENDICES
Appendix A - Responsiveness Summary
Appendix B - Administrative Record
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DECISION SUMMARY
L Site Description
The South Point Plant Site (Plant) is located in Perry Township in the Village of South Point,
Lawrence County, Ohio (Figure 1). The Plant, which covers approximately 610 acres, is located
on a relatively flat portion of the Ohio River terrace within the eastern floodplain of the river.
Along the east side of the Plant, Solida Creek, a small intermittent stream, flows from the
southeast to northwest. Solida Creek and the Ohio River, along with their associated smaller
tributaries represent the natural surface water drainage within the Plant (Figure 2).
The Plant is situated on a relatively uniform silt and fine sand unit which is generally 7 to 10 feet
thick, and is comprised of 50 to 60 percent silt, 30 to 40 percent clay, and 10 percent sand.
Underlying these surface sediments is 70 to 100 feet of unconsolidated, alluvial, and glacial
outwash sediments which rest on bedrock. These sediments comprise the principal aquifer of the
area. Groundwater in the aquifer is present under unconfmed conditions and is found at an
average depth-to-water of 45 feet. In general, groundwater flows toward the Ohio River.
II. Site History and Enforcement Activities
The Plant was constructed in 1943 by the federal government for the production of ammonium
nitrate explosives. In 1946, Allied Chemical purchased the Plant and produced ammonia, urea,
nitrogen fertilizer solution, melamine, formaldehyde, and urea formaldehyde mixtures until 1978.
Ashland Oil purchased the facility in 1979. Ashland demolished and removed many of the
existing Plant's structures and constructed a coal-water fuel pilot plant and a pitch prilling test
plant which formed pitch into small pellets. Both the pilot plant and the test plant have been
dismantled. In 1981, South Point Ethanol (SPE) acquired an 80-acre tract in the middle of the
former production area for ethanol production. In 1985, Cardox, a division of the Air Liquide
Corporation, began leasing a portion of the SPE track for liquid carbon dioxide production. SPE
ceased operation in August 1995. Air Liquide discontinued operation in January 1997. In
addition, portions of the Plant property are leased for agricultural purposes.
Manmade features currently visible on the property include: the Northern Fly Ash Ponds, the
Eastern Disposal Area, Disposal Area D, numerous railroad sidings, the SPE facility, the Cardox
facility, and several miscellaneous structures. The Mid-Plant Area, Coke-Oven Gas Slowdown
Area, and the Ammonium-Nitrate Production Area are locations of activities which may have
caused contamination, however, these areas are not readily identifiable to casual observers (see
Figure 2).
From 1943 to the mid-1980s, plant refuse, coal cinder, small quantities of laboratory chemicals.
asbestos-insulation materials, waste lubrication oils, by-product and off-specification solids (such
as ammonium nitrate, urea, and melamine), and wacte lubrication oils were disposed in the
following areas:
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Eastern Disposal Area - This 13-acre area was in operation from 1946 to 1965. This area
received Plant refuse and debris, coal cinders, and small quantities of chemicals from an on-site
laboratory. It may also have received asbestos insulation materials, ammonium nitrate, urea,
melamine, and waste lubrication oils. Most of the area is covered by grasses, shrubs, and trees
except for the northern portion which lacks vegetation. The Eastern Disposal Area is not lined or
capped with a non-permeable substance, such as clay. Waste material deposited in this area may
go as deep as 30 feet.
Disposal Area D - This 2-acre area received wastes from the mid-1960s until July 1977. This
area received similar waste to that found in the Eastern Disposal Area and also may have
received copper ammonium acetate. The surface of this area is a mixture of slag arid
construction debris which does not support vegetation. The waste in Disposal Area D is about 12
feet deep. This area is in the flood plain of Solida Creek and is severely eroded.
Melamine Ponds - Use of the ponds appears to have begun in the late 1960s. The ponds
received melamine manufacturing process byproducts and at one time contained three to four feet
of a mixture of solids and water. In late 1979, the pond was drained and the solids were
excavated and landfilled. Following excavation, the ponds were regraded and a parking lot and
building were constructed in its place. In 1996, a storage tank that is unrelated to the site, was
removed from the general area of the former melamine ponds. While the soil samples taken were
for verifying completion of the tank removal, field observations indicated possible residual
contamination from the former melamine ponds.
Northern Fly Ash Ponds - The ponds began accepting fly ash and cinders from onsite coal-
fired boilers in the mid-1950s. The fly ash attains its greatest thickness (30 feet) along the east
edge of the ponds. The 40-acre pond area, which is inactive, is not capped or lined but is covered
by grasses, shrubs, and trees.
Other facilities and activities which may have caused contamination include:
The Ammonium Nitrate Production Area - This area is part of the Mid-Plant Area and is near
the center of the site.
The Coke-Oven Gas Slowdown Area - This area is northwest of the Mid-Plant Area. Coke-
oven gas from a coke facility was piped beneath the Ohio River to the Plant and used as a fuel.
Three 25-gallon drip pots are located along the coke-oven gas line to collect condensation.
Reactors and associated iron-oxide catalysts - These units are located on the north side of the
Mid-Plant Area. Thirty-six tons of an iron-oxide were stored in 6 reactors on the site.
Waste lubrication oil disposal activities - A portion of the waste oil was disposed of in the
Eastern Disposal Area.
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Arsenic trioxide packaging disposal activities - These activities which involved burning
wooden kegs in an old railroad car used to transport the kegs from the production area to the
Eastern Disposal Area.
A number of releases have occurred at the site between 1943 and 1979. The four major releases
are described below:
In the mid-1950s nitrogen-phosphate-potash fertilizer stored in the Mid-Plant Area caught fire.
Millions of gallons of water were used to fight the fire. The water washed large quantities of
fertilizer components to the site grounds and storm sewers.
In November 1971, a tank in the Mid-Plant Area ruptured, spilling about 500,000 gallons of
liquid ammonium nitrate. The majority of the contents discharged to a storm sewer that emptied
into the Ohio River.
In November 1977, a portion of the northern dike of the Northern Fly Ash Ponds failed,
releasing significant quantities of fly ash, water and earthem materials from the dike into Solida
Creek.
In February 1978, the eastern dike wall of the Melamine Pond failed, releasing an estimated
100,000 gallons of water containing 1,600 pounds of ammonia nitrogen and 6,000 pounds of
organic nitrogen into the Ohio River through the main outfall. In addition, an unknown quantity
of the solution was discharged to the site grounds.
On September 21, 1984, the Plant was added to the National Priorities List (NPL). The NPL is a
list of sites in the country that are eligible for study and cleanup, if necessary, under the
Superfund program. The U.S. EPA identified Allied-Signal, Inc., Ashland Oil, Inc., and SPE,
Inc. as potentially responsible parties (PRPs) for the site. In May 1987, a Consent Order was
signed by the U.S. EPA, the OEPA, and the PRPs requiring the development of an RI and FS.
On November 26,1991, a letter was sent out by the U.S. EPA outlining the resolution of a
dispute initiated by a letter dated October 18, 1991, from the PRPs concerning the South Point
Plant Site Conceptual Site Model.
Field activities associated with the RI were conducted during the period of 1989 through 1992.
The RI was completed in August 1994 and approved on September 21, 1994. The FS was
completed in May 1997 and approved in July 1997.
III. Highlights of Community Participation
In August 1995, U.S. EPA hosted an Availability Session and released a fact sheet documenting
the conclusion of the RI. Community participation and concerns at the site have been minimal.
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Information repositories have been established at the South Point Mayor's office, 408 Second
Street, and the Briggs Lawrence Library, 317 Solida Road, South Point, Ohio. U.S. EPA
maintains a copy of the administrative record for the site in the information repository. A
Proposed Plan was made available on August 14, 1997. A public meeting was held on August
26, 1997, to discuss the Proposed Plan. Advertisements were placed in local newspapers to
announce the public meeting and comment period. A public comment period for the Proposed
Plan was established from August 14, 1997, to September 12, 1997. The public generally
supports the selected remedy. The responsiveness summary is contained in Appendix A.
The public participation requirements of CERCLA Sections 113 (k)(2)(B) (i-v) and 117 of
CERCLA have been met in the remedy selection process. This decision document present. the
selected remedy for the South Point Superfund site, chosen in accordance with CERCLA, as
amended by SARA, and to the extent practicable, the NCP. The decision for this site is based on
the Administrative Record.
IV. Scope and Role of Response Action
The purpose of this Record of Decision (ROD) is to select the final remedial action for the Plant.
This final remedy controls sources and prevents the further migration of contaminants. The
remedy addresses all media and migration pathways that are considered to present an
unacceptable risk, including landfilled wastes, contaminated soils and groundwater.
Impacted soils in the active area will be removed off-site or consolidated on-site in the Eastern
Disposal Area and capped. If soils from the Coke-Oven Gas Slowdown Area or potential hot-
spots identified in the Mid-Plant Area fail the Toxicity Characteristic Leaching Procedure
(TCLP) and need to be treated prior to off-site disposal, then the statutory preference for
treatment as a principal elerru nt of the remedy would be achieved. However, if the excavated
soils do not need to be treated and because treatment of the additional principal threats at the site
was not found to be practicable, this remedy would not satisfy the statutory preference for
treatment as a prinicipal element of the remedy.
The mobility of constituents to groundwater within the wastes in the inactive area and active area
would be reduced through capping and removal of contaminated soils in specific areas. In
addition, continued operation of the current groundwater pumping system will contain
groundwater on-site and will remove contaminants from groundwater.
This decision is based on an analysis of site risks, described in detail below.
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Vj. Site Characteristics
Onsite work conducted during the Rl included sampling of soil, groundwater, sediment, and
surface water. Onsite sources of contamination at the site were also characterized through the
review of historical records, a well survey, geophysical surveys, and evaluation of historical
aerial photographs. The key findings of the RI are summarized below.
Physical Features
1. Soils
The Plant is underlain by a thick section of unconsolidated material (70 to 100 feet thick). This
material, consisting of alluvial and glacial outwash sediments, forms the major aquifer of the
area. The sediments are composed primarily of fine to medium grained, quartz sand with a low
silt and clay content. The exception to these fine to medium grained sediments is an isolated
coarse sand and gravel lens which is located within the upper portion of the main sand body at
the south side of the Plant. Overlying the sand and gravel is a relatively uniform silt and fine
sand unit which is generally 7- to 10-feet thick. The unit attains a maximum thickness of about
20 feet. In some areas proximal to Solida Creek, the silt and sand unit is underlain by silt and
clay deposits ranging in thickness from 5 to 10 feet.
2. Hydrology
Solida Creek, Willow Creek and the Ohio River represent the natural surface water bodies near
the Plant. Along the east side of the Plant, Solida Creek, a small intermittent stream, flows from
southeast to northwest paralleling the bedrock valley walls. The creek is present in a small 20- to
40-foot deep, steep walled valley, topographically separating the Plant from the bedrock hills. A
small tributary to Solida Creek, Willow Creek, joins it east of the site. Along the west side of the
Plant, the topography drops abruptly to the Ohio River. Over a linear distance of about 2000 feet
the land surface drops approximately 20 feet in elevation to a narrow, flat terrace before
descending another 25 feet to the river creating a relatively steep bank.
3. Hydrogeology
Groundwater at the Plant is found in an unconsolidated aquifer under unconfmed conditions.
The average depth to groundwater is 45 feet. The average saturated thickness of the aquifer is 38
feet. Groundwater velocities have been calculated to range from 3.9 ft/day to 19 ft/day. Four
well fields are present in the Plant vicinity; three Plant well fields (Western, Eastern, and Central
Well Fields) and the South Point Municipal Well Field. In 1983, the Village of South Point and
the Plant reached an agreement to maintain a hydraulic barrier between the Plant and the
municipal well fields. Regional groundwater flow is radial toward the center of the Plant due to
the influence of the Plant well fields.
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4. Ecology
Three state endangered bird species, the mourning warbler, golden-winged warbler, and northern
waterthrush were identified on the site. In addition, the dwarf dandelion, a state threatened plant
species, was identified on the site. The bird species are migratory and are considered to be
transient visitors to the site and not residents. Due to the limited migratory period when the birds
are possibly on the site and the low potential for contaminant exposure via their food sources, the
potential for the site to represent a hazard to these bird species is considered low. The dwarf
dandelion was observed in a disturbed area southwest of the Northern Fly Ash Ponds which is
unlikely to represent a hazard to the species because this area was not reported to have received
waste materials.
An assessment of risks to aquatic organisms potentially exposed to contaminants detected in
surface water and sediments of Solida Creek was conducted, although it is unlikely that this
creek supports a diverse and established assemblage of organisms due to its intermittent nature
(i.e., dry during periods of the year). The low concentrations of contaminants detected in surface
water and sediments from Solida Creek are not expected to represent an ecological hazard.
The findings of the Ecological Assessment indicate that based on the relatively low constituent
concentrations reported in the environmental media (generally low bioconcentration factors of
the compounds of ecological concern and limited evidence of stress to resident biological
communities), there is no evidence that conditions at the Plant represent a threat to ecological
receptors.
5. Contamination
Soils
One hundred an :: ninety-nine soil samples were obtained from 69 onsite locations, including 9
background locations. The background sampling locations were used to determine normal soil
conditions in the area. The soil samples, both surface soil and soil borings, were primarily from the
following areas: the Northern Fly Ash Ponds, the Eastern Disposal Area, Disposal Area D, the Mid-
Plant Area, and the Coke Oven Gas Slowdown Area. These are the primary areas of suspected soil
contamination. Contaminants found in these areas include volatile organic compounds (VOCs and
semi-VOCs), waste specific compounds (ammonia, nitrate/nitrite, and sulfate), and metals (arsenic.
barium, beryllium, cadmium, copper, and selenium). Cyanide was also found in the Coke Oven Gas
Slowdown Area. The contaminants found are consistent with the activities conducted at the site
during the Plant's operational years. In general, contaminants are concentrated within 10 feet of the
surface and decrease rapidly as depth increases.
Groundwater
Groundwater samples were taken from 10 monitoring wells, 7 production wells, 3 residential wells
(two north of the site and one south of the site), 3 observation wells, and 2 municipal wells located
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near the Ohio River. Analytical results indicate that groundwater quality has been affected by the
Eastern Disposal Area, Disposal Area D, the Mid-Plant Area, and the Northern Fly Ash Ponds.
Exceedances of drinking water standards or primary MCLs are restricted to cadmium and
nitrate/nitrite levels. Cadmium levels also exceed the MCL in background samples. Other
constituents, primarily sulfates, iron, and manganese, exceeded groundwater quality standards, or
secondary MCLs. Some high levels of ammonia were also found in the groundwater. In addition,
there are two areas with high values of total dissolved solids (TDS) and high specific conductance.
IDS and specific conductance are two indicators of groundwater quality. The first area is centered
on the northern part of the Northern Fly Ash Ponds immediately adjacent to Disposal Area D. The
second area extends from the Eastern Disposal Area into the Mid-Plant Area. These conditions are
consistent with disposal activities and groundwater flow patterns at the site.
Prior to the start-up of SPE operations at the site in 1981, there had been evidence that the Village
of South Point's municipal wells may have been affected by the groundwater contamination at the
site, particularly nitrate/nitrite contamination. Some of the city's wells were located between the site
and the Ohio River. SPE installed a number of groundwater wells to pump water for cooling off
ethanol production lines and for use in some industrial processes. Excess water from the industrial
process was treated, mixed with the non-contact water, and discharged through an Ohio EPA
National Pollutant Discharge Elimination System (NPDES) permit into the Ohio River. These wells
effectively contained ground water under the site and, when in use, they have eliminated the
potential for contaminated groundwater to affect the city's municipal wells. This existing
groundwater containment system will continue pumping as part of any remedy to ensure the city's
wells are not affected. In addition, the NPDES permit will need to be kept up to date and in
compliance with the Ohio EPA.
Surface Water
Six surface water and six sediment samples were obtained during the RI. Background samples were
collected from Solida Creek and an adjacent creek upstream of the site. The data indicates that there
is no apparent change in surface water quality as it passes through the site, with the exception of a
slight increase in lead content in one sample upstream of the site and one onsite sample.
Sediment
Sediment quality results indicate that the site is not contributing contaminants to the sediments of
Solida Creek.
During the RI, consideration was given to the various site-specific pathways by which contaminants
could migrate from the site. As a part of this process surface runoff and contaminated groundwater
were determined to have incomplete pathway migration. The migration pathway for surface runoff
was considered incomplete because surface water and sediment data from Solida Creek was not
found to be impacted. Solida Creek directly borders the disposal areas at the site and would be
considered the closest surface water body, while the Ohio River is approximately 2000 feet from the
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closest onsite disposal area. Groundwater at the site, while contaminated, was already being
addressed by the groundwater containment system that was in place prior to the RI. As mentioned
previously, the pumping system, while in operation, effectively contains groundwater under the site
and removes mass contaminants. The presence of the containment system alleviated the impact of
contaminated groundwater on the Ohio River. Major releases at the site may also have impacted the
Ohio River. However, because of the short duration of these events and the timeframes that had past
since the releases had occurred, the U.S. EPA determined that these events were not significant
sources of contamination to the Ohio River.
Based on the results of the RI, U.S. EPA examined the threats to human health and the environment
through exposure by ingestion and/or direct contact with contain'nants in ground water, and in
subsurface and surface soils.
VI. Summary of Site Risks
Based on data collected during the RI, the PRPs assessed human health and ecological risks
associated with contaminants detected in groundwater, soils, and surface water within and near the
Plant. This assessment, called a baseline screening, was approved by the U.S. EPA. The baseline
screening was conducted to compare contamination levels at the site with U.S. EPA standards. As
part of the screening, the PRPs considered ways in which people and wildlife could be exposed to
site-related contaminants and whether such exposure could increase the incidence of cancer and
noncarcinogenic (noncancer related) diseases above the levels that normally occur in the study area.
The PRPs also assumed that people could be exposed to site-related contaminants by eating them
(ingestion), breathing them (inhalation), or absorbing them through the skin (dermal contact). The
contaminants of concern are the VOCs, semi-VOCs, metals, and waste-specific compounds of nitrate
and inmonia found in onsite soil and groundwater.
Current land use and reasonably anticipated future use of the land at NPL sites are important
considerations in determining current risks, future potential risks, and the appropriate extent of
remediation. (See "Land Use in the CERCLA Remedy Selection Process," OSWER Directive No.
9355.7-04, May 25,1995). Land use assumptions affect the exposure pathways that are evaluated
in the risk assessment. The results of the risk assessment aid in determining the degree of
remediation necessary to ensure current and long-term protection at the site. The risk assessment
considers present use of the site to determine current risks. It may restrict its analysis of future risks
to the reasonably anticipated future land use.
Current and future land use conditions were assessed by the PRPs in the screening. Under current
land use conditions, risks to three populations were assessed: onsite workers, adult trespassers, and
child trespassers. Under future land use conditions, risks were assessed for on-site construction
workers, on-site industrial workers, adult on-site residents, and child on-site residents. Even though.
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future risks were assessed for residential use, it is reasonably anticipated that future use at the site
will remain industrial.
Because of the uncertainty in segregating and apportioning risks for each source area, the site was
separated into active and inactive areas. The active area included source areas of the site where
industrial activities were concentrated, primarily the Mid-Plant Area and the Coke Oven Gas
Slowdown Area. The inactive area included the waste disposal source areas, Disposal Area D, the
Northern Fly Ash Ponds, and the Eastern Disposal Area. Risks to the current and future users were
assessed separately for the inactive and active areas.
Potential risks to public health for cancer are expressed numerically, i.e., 1x10"* or 1x1(5 .
Carcinogenic risk expressed as 1 x 10"4 means that one out of 10,000 people exposed to contamination
over a 70-year lifetime could potentially develop cancer as a result of the exposure. A carcinogenic
risk of 1x10^ means that one out of 1,000,000 people exposed over a 70-year lifetime could
potentially develop cancer as a result of the exposure. U.S. EPA has established a carcinogenic risk
range from IxlO"4 to 1x10"* in an attempt to set standards for remediation and protectiveness. The
measure of noncarcinogenic risk is termed a hazard index (HI) and is also expressed numerically.
When the HI exceeds 1, there is a potential for adverse health effects.
The risk assessment uses a conservative estimate when evaluating a potential risk. This provides a
high level of protection for public health and the environment. For example, in some of the risk
estimates, the PRPs assume that the site will be developed for future residential land use and that
residents will regularly use contaminated grouhdwater for drinking and bathing. Therefore, the
excess lifetime cancer risk estimates should be regarded as conservative estimates of potential cancer
risk rather than actual representations of true cancer risk.
Current Potential Human Health Risks
Three different groups of people currently could be exposed to contamination at the inactive and
active areas. The three different groups that currently could be exposed include:
Current on-site workers
Adult trespassers
Child trespassers
Workers at the SPE plant were considered to be the current on-site worker population. While the
area occupied by the SPE plant was not considered to be an area that caused contamination at the
site, the risk associated with its proximity to contaminated areas was assessed. In other words,
although there was no evidence that SPE employees were exposed to contaminated media at the site,
the potential for infrequent exposure existed.
Current on-site workers ingesting contaminated groundwater and ingesting, inhaling, and contacting
contaminated surface soils in the inactive area could increase their risk of developing cancer by
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10
7x10^.
Current on-site workers ingesting contaminated groundwater and ingesting, inhaling, and contacting
surface soils in the active area could increase their risk of developing cancer by 8 x 10"*.
Currently on-site adult and child trespassers ingesting, inhaling, and contacting surface soils in the
active area could increase their risk of developing cancer by 9 x 10'3.
Current on-site adult and child trespassers ingesting, inhaling and contacting surface soils in the
active area could increase their risk of developing cancer by 1 x 10"4.
The only exposures that poses a potential noncancerous health risk are to the child and adult
trespasser in the inactive area.
Additionally, for the inactive areas, it was determined that the landfills are considered a continuing
source of groundwater contamination.
Even though the current groundwater pumping system effectively contains contaminated
groundwater on-site and removes mass contaminants, exceedances of MCLs, primarily nitrate/nitrite,
were observed in groundwater beneath the site.
Tables 7-31 thru 7-53 of the South Point Baseline Risk Assessment, found in the South Point
Remedial Investigation Report, dated August 1994, contain individual exposure doses and risk
calculations for each constituent of concern and exposure pathway used to calculate the cumulative
risks for the inactive and active areas.
Future Potential Human Health Risks
In addition to the current exposures described above, four additional groups of people could be
exposed in the future:
Future on-site construction workers
Future on-site industrial workers
Future on-site adult residents
Future on-site child residents
For each of the groups that could be exposed in the future, a conservative approach was taken to
assume that construction workers, industrial workers, and/or residents could potentially work or live
on contaminated portions of the site if no remediation took place. Because of this approach, more
direct and frequent exposures to contamination were assumed, by the PRPs, for future workers and
residents then for current workers. As evidenced below, for the future industrial worker and future
residents this assumption created potentially far greater risk.
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Future on-site construction workers ingesting groundwater and ingesting, inhaling, and contacting
shallow soils in the inactive area could increase their risk of developing cancer by 6 x 10"*.
Future on-site construction workers ingesting groundwater and ingesting, inhaling, and contacting
shallow soils in the active area could increase their risk of developing cancer by 7 x 10'6.
Future on-site industrial workers ingesting groundwater and ingesting, inhaling, and contacting
shallow soils in the active area could increase their risk of developing cancer by 3 x 10"4.
Future on-site adult and child residents ingesting, inhaling, and contacting groundwater, surface
waters, sediments, and shallow soils in the active and inactive areas could inc :ease their risk of
developing cancer by 4 x 10"4.
Exposure to contaminants by future on-site residents in the inactive and active areas and industrial
workers in the active area also poses a noncancerous health risk.
In addition, because of the presence of the current groundwater pumping system, which has
effectively contained contaminated groundwater on-site and removed mass contaminants, an analysis
was conducted to determine the potential off-site impacts to the municipal water supply if the system
was discontinued. Modeling conducted during the RI indicated the groundwater quality off-site
could be affected if the current pumping regime is discontinued, potentially resulting in risk to the
municipal water supply due to exceedances of the MCLs .
Tables 7-31 thru 7-53 of the South Point Baseline Risk Assessment, found in the South Point
Remedial Investigation Report, dated August 1994, contain individual exposure doses and risk
calculations for each constituent of concern and exposure pathway used to calculate the cumulative
risks for the inactive and active areas.
Ecological Risk Assessment
It is possible for wildlife to be exposed to contaminants detected in surface soils, surface waters, and
sediments, either through direct ingestion, inhalation, or contact or through indirect ingestion of
previously exposed plants and animals. However, no evidence of stress to wildlife was observed
during the field investigation.
Resident biota could be exposed to contamination but it is not expected to represent a concern.
VII. Description of Remedial Alternatives
Remedial Action Objectives
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The following remedial action objectives (RAOs) address the media of concern (soil and
groundwater) to provide short and long-term protection of human health and the environment and
to meet the applicable or relevant and appropriate requirements (ARARs).
Surface Soil
Minimize potential ingestion and dermal contact of contaminated surface soils (metals,
carcinogenic polycyclic aromatic hydrocarbons [c-PAHs]) in the inactive and active areas
by current and future human receptors.
Excavate arsenic contaminated soi's in the Mid-Plant Area which exceeds the arsenic
preliminary remedial goal to reduce risk associated with dermal contact and ingestion of
contaminated surface soils by current and future human receptors.
Soil
. Excavate drip pots and the surrounding impacted soil to reduce risk associated with dermal
contact and ingestion of contaminated soils (c-PAHs) associated with the drip pots in this
area by current and future human receptors.
Groundwater
Prevent ingestion of contaminated groundwater (nitrates, ammonia, metals) under the Plant
by future human receptors.
Restore quality of local groundwater under the Plant.
Soil and groundwater remedial technologies were screened, by the PRPs, to determine whether they
were applicable to the constituents of concern, effective, and implementable at the Plant, and
whether they met the RAOs. In addition, relative cost of the remedial technologies was evaluated.
Remedial technologies retained after this initial screening were assembled into remedial measures
for the active area, inactive area, and groundwater. Remedial measures were evaluated for
effectiveness, implementability, and relative cost. The retained remedial measures were assembled
into site-wide remedial alternatives.
Remedial Measures
A description of the retained remedial measures are listed below.
Institutional Controls - deed restrictions, fencing, and monitoring to limit future site usage to
industrial activities and lessen the chance for exposure of local populations to site contaminants.
Surface Controls - slope stabilization, erosion control, enhancement of existing vegetation.
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Vegetated Soil Cover - replace existing poorly vegetated as well as other vegetated areas with a
new soil layer and vegetation.
Single Barrier Cover - replace the existing surface with a low-permeable layer and vegetation. The
single barrier cover will be designed to fully meet Ohio solid waste cap requirements.
Dual Barrier Cover - replace existing surface with a synthetic membrane, a low permeable layer.
and vegetation. The dual barrier cover would be designed to fully meet Ohio hazardous waste cap
requirements.
Excavation - removal of contaminated soils within a specified area.
Stabilization - solidification of excavated soils b'y mixing them with a stabilizing agent.
Consolidation - minimize waste distribution by relocating wastes or excavated soils within a
limited area designed to contain the waste.
Off-site Disposal - transfer waste or excavated soils to an approved off-site landfill.
Bioremediation - use of microorganisms to degrade waste.
Groundwater Decontamination - use of extraction wells to contain and remove mass contaminants
from groundwater flow. Determining when to shut the extraction well system down will require an
evaluation of the contamination remaining in groundwater to determine if there are exceedances of
federal and state standards and/or deviations from the acceptable cumulative Hazard Index.
The retained remedial measures are then combined to form site-wide remedial alternatives. The
alternatives evaluated are listi below.
Summary of Remedial Alternatives
Remedial Alternative RA-1:
No Action
Estimated Cost: $0
Under this alternative, the potential human health and environmental risks associated with exposure
to contaminants would not be mitigated. The inclusion of the "no action" alternative is required by
law to give U.S. EPA a basis for comparison.
Remedial Alternative RA-2:
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Active Area
Institutional controls
Excavation - Coke-Oven Gas Slowdown Areas and the Mid-Plant Area
Treatment: Ex-situ stabilization-Coke Oven Gas Slowdown Areas
Disposal/On-site consolidation in the Eastern Disposal Area
Inactive Area
Institutional controls
Containment:
Single barrier cover - Disposal Area D
Surface controls - Eastern Disposal Area
Groundwater
Institutional controls
- Containment:
Existing pumping containment system
- Discharge:
Ohio River
Estimated Cost: $1,932,750
Remedial Alternative RA-2 incorporates institutional controls, treatment, on-site consolidation,
containment, and off-site discharge.
Remedial Alternative R A-3:
Active Area
Institutional controls
- Excavation - Coke-Oven Gas Slowdown Areas and the Mid-Plant Area
Treatment:
Ex-situ stabilization - Coke-Oven Gas Slowdown Areas
Disposal/On-site consolidation in Eastern Disposal Area
Inactive Area
- Institutional controls
- Containment:
Single barrier cover - Disposal Area D
Surface controls - Northern Fly Ash Ponds
Vegetated soil cover - Eastern Disposal Area
Ground Water
Institutional controls
- Containment:
Existing pumping containment system
Discharge:
Ohio River
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Estimated Cost: $3,314,720
This alternative is identical to RA-2, with the exception of surface controls at the Northern Fly Ash
Ponds and a vegetated soil cover for the Eastern Disposal Area.
Remedial Alternative RA-4
Active Area
Institutional controls
Excavation - Coke-Oven Gas Slowdown Areas and Mid-Plant Area
Off-site disposal
Inactive area
Institutional controls
- Containment:
Single barrier cover - Disposal Area D
Surface controls - Eastern Disposal Area
Ground Water
Institutional controls
Containment:
Existing pumping containment system
Discharge:
Ohio River
Estimated Cost: $2,159,770
Remedial Alternative RA-5
Active Area
Institutional controls
- Excavation - Coke-Oven Gas Slowdown Areas and Mid-Plant Area
- Treatment:
Ex-situ stabilization - Coke-Oven Gas Slowdown Areas
Disposal/On-site consolidation in the Eastern Disposal Area
Inactive Area
Institutional controls
Containment:
Single barrier cover - Disposal Area D
Single barrier cover - Eastern Disposal Area
Ground Water
Institutional controls
Containment:
Existing pumping containment system
Discharge:
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Ohio River
Estimated cost: $3,848,010
Remedial Alternative RA-6
Active Area
- Institutional controls
- Excavation - Coke-Oven Gas Slowdown Areas and Mid-Plant Area
- Treatment:
Ex-situ bioremediation - Coke-Oven Gas Slowdown Areas
Ex-situ stabilization - Mid-Plant Area
- Off-site disposal
Inactive Area
- Institutional controls
- Containment:
Dual barrier cover - Disposal Area D
Vegetated soil cover - Northern Fly Ash Ponds
Dual barrier cover - Eastern Disposal Area
Ground Water
Institutional controls
Containment:
Existing pumping containment system
Discharge:
Ohio River
Estimated Cost: $7,927,550
VIII. Evaluation of Alternatives
The National Contingency Plan (NCP), Section 300.430 (f)(I), requires that the alternatives be
evaluated on the basis of the nine evaluation criteria.
U.S. EPA used the nine criteria to evaluate each of the alternatives. The evaluation criteria are: (1)
Overall protection of human health and the environment; (2) Compliance with Applicable or
Relevant and Appropriate Requirements (ARARs); (3) Long-term effectiveness and permanence:
(4) Reduction of contaminant toxicity, mobility, or volume through treatment; (5) Short-term
effectiveness; (6) Implementability; (7) Cost; (8) State Acceptance, and (9) Community Acceptance.
These criteria are summarized below and followed by a comparison of the alternatives with regard
to these nine evaluation criteria. Table 1 is a summary of the analysis of all the alternatives.
Threshold Criteria
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The selected remedy must meet the following threshold criteria;
1. Overall protection of human health and the environment This criterion is used to evaluate
whether an alternative eliminates, reduces, or controls threats to public health and the
environment through institutional controls, engineering controls, or treatment.
2. Compliance with Applicable or Relevant and Appropriate Requirements f ARARs) This
criterion is used to evaluate whether the alternative meets federal and state environmental
statutes, regulation, and other requirements that pertain to the site or whether a waiver is
justified.
Primary Balancing Criteria
The balancing criteria are used to compare the effectiveness of the remedies.
3. Long-term effectiveness and permanence This criterion considers whether an alternative
permanently maintains protection of human health and the environment, and the effectiveness
of such protection.
4. Reduction of contaminant foxicitv. mobility, or volume through treatment This criterion is
used to evaluate whether a particular treatment reduces the harmful effects of principal
contaminants, their ability to move in the environment, and the amount of contamination present.
5. Short-term effectiveness This criterion is used to consider the length of time needed to
implement an alternative and the risks the alternative poses to workers, residents, and the
environment during implementation.
6. Implementabilitv This criterion is used to conside .he technical and administrative feasibility
of implementing the alternative, such as relative availability of goods and services.
7. Li?St This criterion is used to estimate capital and operation and maintenance costs, as well as
present worth costs. Present worth cost is the total cost of an alternative over time in terms of
today's dollars.
Modifying Criteria
The following criteria are used to assess support agency and community response to the alternatives.
8. State Acceptance This criterion is used to consider whether the State agrees with U.S. EPA's
analyses and recommendations of the RI/FS and the Proposed Plan.
9. Community Acceptance This criterion is used to evaluate the public comments and will be
addressed in the Record of Decision (ROD). The ROD will include a responsiveness summary
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that presents public comments and U.S. EPA's responses to those comments. Acceptance of
the recommended alternative will be evaluated after the public comment period.
1. Overall Protection of Human Health and the environment
RA-1 is not protective. RA-2 through RA-6 are protective. Implementation of RA-2, RA-3,
RA-5, and RA-6 would result in reduction of mobility through treatment, while implementation
of RA-6 would also result in reduction of toxicity through treatment. RA-1 and RA-4 do not
involve treatment for the reduction of toxicity, mobility, and volume of wastes. Short-term risks
posed to on-site construction workers during implementation of RA-2 through RA-6 can be
effectively mitigated by using engineering controls.
2. Compliance with Applicable or Relevant and Appropriate Requirements (ARARs)
RA-1 would not meet the remedial action objectives and would not comply with ARARs. RA-2
through RA-6 comply with ARARs, with the exception of the cover system proposed for the
Eastern Disposal Area in RA-2, RA-3, RA-4, and RA-5.
RA-1, the no action alternative, will not comply with location-specific ARARs for the protection
of floodplains and wetlands. RA-2 through RA-6, when implemented, will comply with all
location-specific ARARs. RA-1 will not comply with chemical-specific ARARs for inorganic
health-based COCs. RA-2 through RA-6, when implemented, will comply with all chemical-
specific ARARs. These five alternatives include a site-wide groundwater monitoring program
to determine the effectiveness of aquifer restoration and compliance with groundwater remedial
goals. RA-1 will no* comply with action-specific ARARs concerning management of solid and
hazardous waste and the protection of groundwater. RA-2 through RA-5, when implemented.
will partially comply with action-specific ARARs. Implementing surface controls (RA-2), a
vegetated soil cover (RA-3), or a single barrier cover (RA-4 and RA-5) in the Eastern Disposal
Area, will not meet the regulations regarding final closure and post-closure care of hazardous
waste landfills. An ARAR waiver is justifiable for a single barrier cover based on 'he
"equivalent standard of performance" criteria. Even though there is evidence that potentially
hazardous material was disposed of in the Eastern Disposal Area, the Rl has determined that
contaminants related to these potentially hazardous materials have been detected at only
moderate and not high levels. Therefore, placement of a single bamer, solid waste cap, meeting
solid waste ARARs, on the Eastern Disposal Area is acceptable.
3. Long-term effectiveness and permanence
Waste would remain on-site after the implementation of any of the alternatives. RA-1 would not
reduce risks. Therefore, the magnitude of residual risk would be the same as current risks.
Residual risks associated with RA-2 through RA-6 would include contained wastes in the
inactive area which can be controlled through cover system maintenance and institutional
controls. Residual risks remaining in the active area are within the U.S. EPA acceptable risk-
based range. Risks remaining in the groundwater will be acceptable once the aquifer is restored.
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Since waste would remain on-site after implementation of all of the alternatives, measures would
be implemented to control risks associated with the wastes, except for RA-1. Deed restrictions
would prohibit future residential use of the Plant property. The Plant perimeter fence would
reduce the potential for future trespasser exposure to soils in the active area and inactive area in
RA-2 through RA-6.
Except for RA-1, all of the alternatives would provide covers over the remaining wastes in the
inactive area. Cover systems are frequently used to control land disposed wastes and are proven
to be reliable in eliminating exposure to wastes. Single and dual barrier covers would provide
an equivalent level of protection from direct exposure, unless a barrier failure occurs. Similarly,
vegetated soil covers would provide adequate protection to minimize direct exposure.
Institutional controls in the Northern Fly Ash Ponds would function as reliably as vegetated soil
covers (RA-2 and RA-4) since this area currently sustains thick vegetation. The waste disposal
areas would be included within the Plant perimeter fence to reduce the potential for exposure and
a cover inspection program would be implemented with each alternative (except RA-1) to
evaluate the need for repairs to the covers. In addition, a long term groundwater monitoring
program would be conducted to evaluate the effectiveness of the cover system.
Exposure to groundwater would be controlled in each alternative, excluding RA-1, by
maintaining the existing groundwater pumping system and implementing deed restrictions and
groundwater monitoring. The existing pumping system at the Plant has been proven to be
reliable in containing groundwater plumes within the Plant boundaries and removing mass
contaminants. Deed restrictions would adequately prohibit the potential for the water beneath
the Plant to be used for residential purposes. Long-term groundwater monitoring would be
implemented with RA-2 through RA-6 to verify the effectiveness of the groundwater plume
containment system.
4. Reduction of contaminant toxicity, mobility, or volume through treatment
RA-2, RA-3, and RA-5 include ex-situ stabilization of approximately 375 yd3 of soil from the
active area. PA-6 would implement ex-situ bioremediation of approximately 375 yd3 of soil
from the Coke-Oven Gas Slowdown Areas and ex-situ stabilization of approximately 4000 yd3
of soil from the Mid-Plant Area. RA-t and RA-4 would not implement treatment.
5. Short-term effectiveness
RA-2 through RA-6 would require less than 30 years to achieve adequate protection. RA-1
would not achieve protection. The time controlling factor is aquifer restoration. However it is
highly unlikely that 30 years would be required, since groundwater pumping at the Plant has
proven to be effective at contaminant removal, as indicated by the production well monitoring
data. An average of one well per calender-year quarter exhibits concentrations above the
remedial goals for nitrates and ammonia. In general, low concentrations of nitrates and ammonia
exist across the site.
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6. Implementability
RA-2 through RA-6 are all achievable and operable at the Plant. RA-2, RA-3, RA-5, and RA-6
require treatment which may result in minor implementation and operation and maintenance
concerns. Except for RA-1, all of the remedial alternatives involve implementing cover systems
of various types in the inactive area. These cover systems are easily implemented. The
equipment, materials and specialists required for the implementation of RA-2 through RA-6 are
all available.
7. Cost
The implementation costs increase with the increasing level of technical requirements for cover
systems in the inactive area. RA-2, RA-4, and RA-5 are considered to be the most cost effective
that also provide acceptable levels of protection.
8. State Acceptance
The State of Ohio has indicated a willingness to concur with this decision. A written
confirmation is expected by September 30,1997 and will be added to the administrative record
upon receipt.
9. Community Acceptance
Residents in the vicinity of the Plant are in favor of the selected remedy since it will prevent the
further migration of contaminants and remove contaminant sources.
Selected Remedy
The selected remedy is a slight modification to Remedial Alternative RA-S. The modified RA-5 was
proposed as Remedial Alternative RA-5 A in the Proposed Plan.
Remedial Alternative RA-5A
Active Area
Institutional controls
- Excavation:
Mid-Plant Area and Coke-Oven Gas Slowdown Areas
Disposal:
On-site consolidation in Eastern Disposal Area - Mid-Plant Area
Off-site disposal - Mid Plant Area and Coke Oven Gas Slowdown Area
Inactive area
Institutional controls
- Containment:
Consolidation and placement of a Single barrier cover - Disposal Area D
Single barrier cover - Eastern Disposal Area
Surface controls - Northern Fly Ash Ponds
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Ground Water
Institutional controls
Containment:
Existing pumping containment system
- Discharge:
Ohio River
Estimated Cost - $3,910,800
RA-5A includes institutional controls for the Active Area, Inactive Area, and groundwater.
For groundwater remediation, RA-5A includes containment and removal of mass contaminants
through continued operation of the existing system. Monitoring will be conducted. Preliminary
remedial goals (PRGs) established for groundwater in the FS can effectively assess the progress of
groundwater containment and removal of mass contaminants. Table 2 contains groundwater PRGs
for the South Point Plant site. However, determining when to shut the system down will require an
evaluation of the contamination remaining in groundwater to conclude if there are exceedances of
maximum contaminant levels (MCLs) and/or deviations from the acceptable cumulative Hazard
Index (HI). It is necessary to continue, pumping of the site until the combined HI of all
contaminants is less than 1.
For the Inactive Area, RA-5A proposes, single barrier caps for the Eastern Disposal Area and
Disposal Area D, similar to what is proposed in RA-5. Some detail and clarification has been added
to the remediation of Disposal Area D, involving consolidation and stabilization of the area as
described in RA-2, RAO, RA-4, and RA-5 because of its precarious location on the slope of Solida
Creek. Even though there is evidence that potentially hazardous material was disposed of in the
Eastern Disposal Area, the RI has determined that contaminants related to these potentially
hazardous materials have been detected at only moderate and not high levels. Therefore, the remedy
supports the placement of a single barrier, solid waste cap, meeting solid waste ARARs, on the
Eastern Disposal Area. Under this scenario the U.S. EPA invokes the CERCLA waiver for
Equivalerfl ftftflru%d of Perfcnnance for hazardous waste ARARs. In addition, the U.S. EPA is
recommending surface controls for the Northern Fly Ash Ponds, as described in the RA-3.
For the Active Area, including the Mid-Plant Area and the Coke-Oven Gas Slowdown Area, RA-5A
proposes excavation similar to that described in the FS for each of the alternatives requiring action.
However, RA-5 A includes a combination of on-site consolidation and off-site disposal for excavated
soils as variously described in RA-2, RA-3, RA-4, RA-5, and RA-6. Treatment of soils from the
Coke-Oven Gas Blowdown Areas has been replaced by off-site disposal as described in RA-4.
TCLP analysis of excavated material will be performed to determine if treatment is necessary prior
to off-site disposal.
For the Mid-Plant Area, arsenic contamination in soils was determined to be the main chemical of
concern driving clean-up. Upon reviewing the concentrations of arsenic present at the site, the U.S.
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EPA determined that a natural break in the data extended to a range of 40 ppm. The U.S. EPA
supports this value as a clean-up standard for arsenic in soils. U.S. EPA's assessment of the
appropriate exposure assumptions and risk associated with a 40 ppm clean-up standard is that the
value is still well within the acceptable risk range of 1 x 10"4 to 1 x 10"6. The value actually falls
around 1.7 x 10'5. The U.S. EPA supports a strict set of guidelines for clean-up of the Mid-Plant
Area. These guidelines are summarized below:
A boundary to the Mid-Plant area, roughly consistent with current estimated boundaries, will be
delineated in the field. This boundary will then be used to define the extent of excavation in the
Mid-Plant area.
The delineated Mid-Plant area will be divided into a northern and southern portion. In dividing
the Mid-Plant Area, the southern portion should contain all sampling points that based on the
existing RI data indicate arsenic to be present above 40 ppm.
Remedial Design sampling will be conducted to delineate the lateral extent of arsenic
contamination in the first 1.5 feet of soil within the Mid-Plant area by gridding both the northern
and southern portions.
The northern portion will be sub-divided into 300 ft. grids. At a minimum, four to six samples
will be taken in each grid and composited for analysis. If a composite sample exceeds the clean-
up standard, either the grid may be subdivided into smaller grids to further delineate the areas
within the 300 ft. gr^ exceeding the clean-up standard to be excavated or all the soils within the
300 ft. grid can be excavated to a depth of 1.5 feet. Post excavation sampling of all grids
excavated in the northern portion of the site will be required. Post-excavation sampling will be
from the bottom of the hole and will include, at a minimum, four to six samples. Samples can
be composited for analysis. Sidewall sampling will not be required.
The southern portion will be sub-divided into 100 ft. grids. At a minimum, four to six samples
will be taken in each grid and composited for analysis. If a composite sample exceeds the clean-
up standard, eithet the grid may be subdivided into smaller grids to further delineate the areas
within the 100 ft. grid exceeding the clean-up standard to be excavated or all the soils within the
100 ft. grid can be excavated to a depth of 1.5 feet. Post excavation sampling of all grids
excavated in the southern portion of the site will be required. Post-excavation sampling will be
from the bottom of the hole and will include, at a minimum, four to six samples. Samples can
be composited for analysis. Sidewall sampling will not be required.
When sampling a grid space that contains concrete slabs, sampling will be required adjacent to
the concrete slabs. If the analytical results indicate concentrations below the arsenic clean-up
standard no further sampling will be required. If the concentrations exceed the arsenic clean-up
standard, excavation will be conducted up to the slab. The slab and any soils underneath need
not be excavated. However, samples will need to be taken underneath the existing concrete slab
by coring through the cement to characterize the soil underneath. In addition, further evaluation
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on remedial alternatives may be necessary depending on the arsenic concentrations found
underneath a slab.
If initial grid characterization efforts indicate :hat a grid will require excavation, an x-ray
fluorescence (XRF) field screening instrument may be used to evaluate smaller grids and/or
locate hot-spots within a grid. This same instrument will also be used to conduct post-
excavation characterization. However, limitations of the use of the XRF instrument as a field-
screening in-situ tool need to be taken into consideration. These limitations include the ability
of the instrument to detect low concentrations of arsenic, possibly around 30 to 40 ppm, and
detecting concentrations at depths beyond the initial few millimeters of topsoil. Additionally,
confirmational sampling and laboratory analysis will be required.
If post-excavation characterization indicates that the base of the grids require further excavation,
the additional excavation will be done in 6-inch lifts.
Two existing RI samples, SPSS-11 and SPSS-15, taken outside of the current estimated
boundary of the Mid-Plant area exceed the proposed clean-up standard of 40 ppm. Additional
sampling in these areas will be required. The existing sampling point will be used as a center
for deriving four 100 ft. grid boxes. At a minimum, four to six samples will be taken in each
grid and composited for analysis. If the composited analysis results in an exceedance of the
clean-up standard, either the grid may be subdivided into smaller grids to further delineate the
areas within the 100 ft. grid exceeding the clean-up standard to be excavated or all the soils
within the 100 ft. grid can be excavated to a depth of 1.5 feet. As an alternative, the perimeter
edge of the grid may be sampled to define whether the outer edge of the grid is below the clean-
up level. If additional sampling within the grid or at the perimeter of the grid indicates that the
contamination is contained within the grid space, then the excavation of the contaminated soils
to a depth of 1.5 feet would be required. Post-excavation sampling will be from the bottom of
the hole and will include, at a minimum, four to six samples. Samples can be comported for
analysis. Sidewall sampling will not be required. If additional sampling within the gnd or at
the perimeter of the grid indicates that arsenic contamination could extend beyond the four grids,
then 100 ft. grids will be extended and additional sampling conducted until the lateral extent of
the contamination is delineated. Once the extent of the contamination is defined, appropriate
remedial options will be examined and considered, including engineering controls and
institutional controls. The Agencies would like to emphasize that should the possibility arise that
contamination extends beyond the original 200 ft. grids, further characterization of these areas
will need to be performed. Additional characterization and, if needed, potential remedial
alternatives will be discussed after the data has been collected and reviewed.
Soils in the Mid-Plant area and the two sampling locations to the south of the Mid-Plant area that
are one order of magnitude above (400 ppm), the clean-up standard established by the U.S. EPA
(40 ppm), will be disposed off-site at a proper facility. In addition, soils that are believed to
contain arsenic concentrations greater than an order of magnitude above the clean-up standard
shall be segregated on-site until the excavation activities are complete. Following excavation.
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the segregated soils would be sampled in accordance with applicable guidance for determining
the quality of stockpiled soils. Those soils found to contain arsenic concentrations an order of
magnitude above the clean-up standard would be disposed of off-site. Larger areas of arsenic
contaminated surface soils, which are at levels below 400 ppm but above 40 ppm, will be
consolidated and disposed on-site in the Eastern Disposal area, prior to construction of the cap.
The removed soils will then be included under the single barrier, solid waste cap.
Even though clean-up at the Mid-Plant Area would be based on exceedances of the 40 ppm
clean-up level for arsenic and confirmational sampling will only be required for arsenic, the
clean-up must meet the cumulative risk level of 2.3 x 10"s as well as the arsenic risk level of 1.7
x 10"5. This will help account for the additional carcinogenic risk of 6 x 10* calculated in the
Mid-Plant Area for the additional chemical parameters. The data from the arsenic confirmational
sampling would then be used in a risk analysis of the residual arsenic risk present in that
particular exposure area. The residual arsenic risk would be added to the risk number calculated
for the additional chemical parameters of 6.0 x 10"6 and compared to the overall cumulative risk
of 2.3 x 10'5. Any additional removal would be based on exceedances of the cumulative target
risk number of 2.3 x 10~5. This clean-up will proceed using the assumption that the 6 x 10"* risk
number represents the level of residual risk in the Mid Plant area due to the other carcinogenic
compounds. However, should any future data suggest that this assumption is inaccurate, this
decision can be revisited. In addition, the U.S. EPA or the Ohio EPA reserve the right to
conduct any future sampling they believe necessary at the site.
For the Coke-Oven Gas Slowdown Area, even though the constituents driving this clean-up are
different from the Mid-Plant Area, a cumulative risk of 2.3 x 10~5 will also need to be achieved for
this ciean-up. Confirmational sampling would include the entire list of soils PRGs as shown in
Table 2. As mentioned previously, any soils removed from the Coke-Oven Gas Slowdown Area
will be properly disposed off-site.
Also, as part of RA-5A, some additional characterization wii; be required in the area of the former
melamine ponds during the remedial design. The extent of this additional data collection will be
determined during the remedial design planning phase.
The estimated cost of RA-5A is about $62,800 more than that for RA-5, not including any costs
associated with the additional melamine pond characterization. Additional cost is associated with
off-site disposal for material excavated from the Coke-Oven Gas Slowdown Area and potentially
the Mid-Plant Area.
RA-5A complies with all location, chemical, and action specific ARARs listed in Tables 1.8, 1.9.
and 1.10 of the Final South Point FS dated June 1997. The FS is contained in the Administrative
Record.
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IX. Statutory Determinations
The following is a brief description how the selected remedy meets the statutory requirements of
Section 121 of CERCLA.
Protection of Human Health and the Environment.
U.S. EPA's preferred alternative is believed to provide the best balance of trade-offs among
alternatives with respect to the criteria used to evaluate remedies. Current and potential future risks
to human heal in and the environment from the contaminated groundwater will be significantly
reduced provided that the landfill caps remain intact, the groundwater containment system is
maintained, and site access and use restrictions are strictly enforced. The bulk of the contamination
source would remain on-site, but the mobility and volume would be reduced by the caps, and active
groundwater containment system. No unacceptable short-term risks or cross-media impacts will be
caused by implementation of the selected remedy.
Compliance with Applicable or Relevant and Appropriate Requirements.
The Remedial Action Objectives that the selected remedy must meet are described in Section VIII
above. The ARARs for the selected remedy are listed in Tables 1.8,1.9, and 1.10 of the Final South
Point FS dated June 1997. They include the Ohio regulations for applicable action -specific
ARARS for landfill closure (OAC 3745-27-1 I/A, B, G and OAC 3745-27-14/A).
Cost-Effectiveness
The U.S. EPA believes that the selected remedy complies with ARARs and is cost-effective in
mitigating the principal risk posed by contaminated groundwater. Section 300.430 (f) (ii) (D) of the
NCP requires U.S. EPA to assess cost-effectiveness by evaluating all alternatives which satisfy the
threshold criteria: protection of human health and the environment and compliance with ARARs,
with three additional balancing criteria: long-term effectiveness and permanence; reduction of
toxicity, mobility, and volume achieved through treatment; and short-term effectiveness, to
determine overall cost-effectiveness. The selected remedy meets these criteria and provides overall
effectiveness in proportion to its cost.
I Jtiliyation of Permanent Solutions and Alternative Treatment (or resource recovery) Technologies
to the Maximum Extent Practicable (MEP1.
U.S. EPA believes that the selected remedy represents the maximum extent to which permanent
solutions and treatment technologies can be utilized in a cost effective manner for the South Point
Plant Landfill site. Of those alternatives that are protective of human health and the environment
and comply with ARARs, the U.S. EPA has determined that the selected remedy provides the best
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balance of trade-offs in terms of long-term effectiveness and permanence; reduction of toxicity,
mobility, short-term effectiveness; implementability; and cost.
Preference for Treatment as a Principle Element.
As stated previously, if the soils from the Coke-Oven Gas Blowdown Areas, or the potential hot
-spots identified in the Mid-Plant Area, fail the TCLP and need to be treated prior to off-site
disposal, then the statutory preference for treatment as a principle element of the remedy will be
achieved. However, if the excavated soils do not need to be treated, or treatment of the additional
principle threats at the site are not found to be practicable, this remedy will not satisfy the statutory
preference for treatment as a principle element of the remedy.
Based on the information available at this time, therefore, U.S. EPA believe the preferred alternative
would protect human health and the environment, would comply with ARARs, would be cost-
effective, and would utilize permanent solutions and alternative treatment technologies or resource
recovery technologies to the maximum extent practicable.
Xi Explanation of Significant Changes
There are no significant changes from the recommended alternative described in the proposed plan.
XI State Concurrence
The State of Ohio has indicated a willingness to concur with this decision. A written confirmation
is expected, and will be added to the administrative record upon receipt.
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FIGURES
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Figure 1
Vicinity Map
South Point Plant
South Point, Ohio
VIRGINIA
Lexington
KENTUCKY
South Point
Plant Site
OHIO
W. VIRGINIA
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Fly Ash
Ponds
Central
Wellfields
Mid-Plant
Area = Easternv'
Area
Melamlne >\
Pond
Area
Municipal
vyeii
Reid
KEY
Property Boundary
Site Buildings
South Point
Sewage Treatment
Plant
Figure 2
Site Map
South Point Plant,
South Point, Ohio
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TABLES
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TABLE 1
EVALUATION TABLE
The Evaluation Table below shows that the recommended alternative (Alternative RA-5A) would provide the best balance with respect to
the nine criteria. U.S. EPA cannot select an alternative unless it is fully protective of human health and the environment and compliant with
the applicable or relevant and appropriate requirements.
EVALUATION TABLE
Evaluation
Criteria
1. Overall Protection of
Human Health &
Environment
2. Compliance wilb ARARs
3. Long-term Effectiveness
and Permanence
4. Reduction of Toxkity,
Mobility, or Volume
Through Treatment
5. Short-term Effectiveness
6. ImplcmcnUbilily
7. Cost (Estimated)
8. Support Agency
Acceptance
9. Community Acceptance
Alternative
RA-I
o
a
a
a
a
SO
Alternative
RA-2.
a
a
a
a
$1,932,750
Alternative
RA-3
D
D
a
O
a
$33 14,720
Alternative
RA-4
D
a
a
a
$2,159,770
Alternative
RA-5
tf
O
a
S3.848.010
Alternative
RA-SA
Ou
a
a
$3,910,800
Alternative
RA-6
O
a
$7,927,550
The State of Ohio EPA fully accepts and supports Alternative RA-SA
Community acceptance of the recommended alternative will be evaluated after the publk comment period
- Fully meets criteria D - Partially meets criteria Q - Does not meet criteria
'This alternative would require that U.S. EPA grant a waiver of certain Ohio EPA hazardous waste requirements.
'The Ohio EPA has agreed that such a waiver is appropriate in this instance for this alternative.
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Table 2 South Point Plant Preliminary Remedial Goals (PRGs)
Constituent
Soil
1,1 - Dichloroethene
B enzo(a)anthracene
Benzo(a)pyrene
Benzo(b)flouranthene
Benzo(k)flouranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Antimony
Arsenic
Barium
Beryllium
Cadmium
Chromium
Thallium
Vanadium
Groundwater
Ammonia
Arsenic
Beryllium
Cadmium
Copper
Manganes
Nickel
Nitrate
PRGs
Soils (mg/kg) - Groundwater (mg/1)
10
18
1.8
18
180
1,800
1.8
18
500
40
88,000
14
630
6,300
100
8,800
30
0.05
0.004
0.005
3.8
1.4
2
10
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APPENDIX A
Responsiveness Summary
-------
RESPONSIVENESS SUMMARY
SOUTH POINT
SOUTH POINT, LAWRENCE COUNTY, OHIO
PURPOSE
This responsiveness summary has been prepared to meet the requirements of Sections
113(k)(2)(B)(iv) and 117(b) of the Comprehensive Environmental Response, Compensation, and
Liability Act of 1986 (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act of 1986 (SARA), which requires the United States Environmental
Protection Agency (U.S. EPA) to respond to each of the significant comments, criticisms, and
new data submitted in written and oral presentations on a proposed plan for remedial action. The
responsiveness summary provides a summary of residents' comments and concerns identified
and received during the public comment period, and U.S. EPA's responses to those comments
and concerns. All comments received by U.S. EPA during the public comment period were
considered in the selection of the remedial alternative for the Plant. The responsiveness
summary serves two purposes: it summarizes community preferences and concerns regarding the
remedial alternatives, and it shows members of the community how their comments were
incorporated into the decision-making process.
This document summarizes written and oral comments received during the public comment
period of August 14, 1997 to September 12, 1997. The comments have been paraphrased to
efficiently summarize them in this document. The public meeting was held at 7:00 p.m. on
August 26, 1997, at the South Point City Council Chambers, South Point, Ohio. A full transcript
of the public meeting, ?« well as all site related documents, are available for review at the
Information Repositories, located at the South Point Mayor's office, 408 Second Street, and the
Briggs Lawrence Library, 317 Solida Road, South Point, Ohio. Questions and one official
comment were received during the public meeting. One comment, from a potentially responsible
party was mailed to U.S. EPA.
OVERVIEW
Community Concerns
1. Comment: A representative from a local chamber of commerce submitted an official
comment during the public meeting. Because of the size of the South Point Plant property
and the apparent value to attract industry, the representative requested that the U.S. EPA
examine the possibility of releasing portions of the property that are not impacted or affected
by Superfund remedial activities.
Response: U.S. EPA is willing to work with local groups, local governments, and landowners
at the site and discuss options for releasing portions of the property, not related to the
Superfund activity, for industrial purposes. Nationally, U.S. EPA has begun to examine the
possibility of deleting or releasing parcels of certain Superfund sites as part of U.S. EPA's
Superfund Reforms. Efforts to encourage redevelopment of contaminated sites has resulted
-------
in the formation of the EPA NPL Partial Deletion Workgroup. The Workgroup is developing
a pilot program to delete portions of sites on the NPL. If possible, results of the pilot
program will be applied to the South Point Plant.
Potential Responsible Parties (PRPs) Concerns
1. Comment: One PRP was concerned with the additional sampling proposed for the area that
contained the former melamine ponds. In particular, the PRP wanted to "reiterate the factual
basis on which the melamine pond was evaluated and eliminated as an issue at the site" and
"express our concern that this speculative, investigative element will only add further delay
and cost to the process with no commensurate increase in overall remedy protectiveness."
Response: The U.S. EPA acknowledges that decisions were made in the past to eliminate
characterization of the former melamine pond area during the course of the remedial
investigation. This decision appears to be based on the assumption that the area in question
had undergone some clean-up work in the past. At this stage, U.S. EPA has no intention of
reopening the remedial investigation, however, based upon data collected during an
investigation associated with a tank pull near the former pond area, U.S. EPA believes that
enough questions have been raised that additional limited characterization of the area needs
to be conducted during the remedial design. While the data collected as part of the tank pull
does not conclusively show residual contamination from the former ponds, observations in
the field suggested that past decisions to eliminate characterization may have been premature.
Keeping in mind that additional characterization will be limited, U.S. EPA does not believe
that the addition of this element to the remedial design will result in any excessive delays or
costs to the project. At the same time, because of the lack of data previously collected in the
area, additional characterization will provide the information necessary to address questions
concerning the former ponds. U.S. EPA would also like to emphasize, that at this stage only
limited data collection efforts have been proposed. Because of the uncertainty surrounding
the former melamine pond area, U.S. EPA feels it is prudent to collect and analyze additional
data prior to making further decisions on the need for any additional investigations or
response actions.
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APPENDIX B
Administrative Record
-------
0.8. ENVIRONMENTAL PROTECTION AGENCY
REMEDIAL ACTION
ADMINISTRATIVE RECORD
TOR
SOUTH POINT PLANT SIT!
SOUTH POINT, OHIO
ORIGINAL
AUGUST 6. 1997
NO. PATH
1 06/03/81
2 06/07/81
3 04/20/83
4 04/27/83
5 12/20/85
6 04/21/87
8 10/00/88
10
11
12
02/00/89
02/00/89
03/00/89
05/00/89
AUTHOR
Shields, B.,
Allied
Corporation
Williams, D.,
Ashland Oil,
Inc.
Byrara, S.,
Ecology and
Environment,
Inc.
Perenchio, L.,
Ecology and
Environment,
Inc.
Constantelos,
B., U.S. EPA
U.S. EPA/
Ohio EPA
7 OE/05/87 U.C. EPA
Geraghty 6
Miller, inc.
Geraghty &
Miller, Inc.
Geraghty &
Miller, Inc.
Geraghty 6
Miller, Inc.
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
Addressees
Respondents
Public
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
Public
/DESCRIPTION PACKS
Notification of 2
Hazardous Waste Site
Notification of
Hazardous Waste Site
Site Inspection Report 12
for the Allied Chemical
Bthanol Plant Site
Preliminary Assessment 6
for the South Point/
Allied Chemical Bthanol
Plant Site
Sample Letter re: Notice 6
of Potential Responsibility
(UNSIGNED) w/Attached PRP
Mailing List
Administrative Order on 39
Consent re: the South
Point Plant Site
News Release: EPA Seeks 2
Public Comment, on South
Point Plant Investigation
Technical Memorandum: 13
Site Well Survey and
Locations of Proposed
Monitor Wells at the
South Point Plant Site
RI/PS Quality Assurance 229
for the South Point
Plant Site
RI/FS Sampling Plan for 206
the South/Point Plant
Site
Technical Memorandum: ~i\
Results of the Geophysical
Survey Conducted at the
South Point Plant Site
Pact Sheet: Environ- 6
mental Investigation to
Begin at the South Point
Plant Site
-------
South Point XR
Original
Pag* 2
MO. PATH
AUTHOR
RKCIPIKMT
TXTLK/DBSCRXPTION
13 05/02/89 U.S. EPA .
Public
14 04/00/90 U.S. EPA
15 10/00/90 Geraghty &
Miller, Inc.
16 05/00/91 Geraghty &
Nailer, Inc.
17
18
19
20
11/26/91
01/30/92
04/14/92
08/00/92
Niedergang, N.,
U.S. EPA and
J. Tiell,
Ohio EPA
Geraghty &
Miller, Inc.
Geraghty &
Miller, Inc.
U.S. EPA
21 02/02/93 Geraghty s,
Miller, Inc.
22
23
24
25
Public
U.S. EPA
U.S. EPA
Ford, R.,
Allied-Signal,
Inc.; et al.
U.S. EPA
U.S. EPA
Public
U.S. EPA
02/02/93
08/00/94
08/00/94
08/00/94
Geraghty &
Miller, Inc.
Geraghty &
Miller, Inc.
Geraghty &
Miller, Inc.
Geraghty &
Miller, Inc.
U.S.
U.S.
U.S.
U.S.
EPA
EPA
EPA
EPA
News Release: U.S. EPA 2
Begins Study of South
Point Plant; To Hold
Information Session
May 9, 1989
Fact Sheet: Community 2
Update Concerning the
South Point Plant Site
Preliminary Remedial 47
Technologies Assessment
for the Allied-Signal
South Point Plant Site
Source Area Technologies 115
Assessment for the Allied-
Signal South Point Plant
Site
Letter re: South Point 5
Plant Site Conceptual Site
Model Dispute Resolution
RI/FS Ground-Water Flow 106
and Solute Transport
Analysis for the South
Point Plant Site (FINAL
REPORT)
Ecological Assessment 272
of the South Point Plant
Site
Fact Sheet: Community 4
Update Concerning the
South Point Plant Site
Baseline Risk Assessment 186
for the South Point Plant
Site: Volume I (Text,
Tables and Figures)
Baseline Risk Assessment 566
for the South Point Plant
Site: Volume II (Appendices)
Remedial investigation 415
Report: Volume 1 (Text)
Remedial Investigation 229
Report: Volume 2 (Tables)
Remedial Investigation 166
Report: Volume 3 (Figures
and Plates)
-------
South Point AR
Original
Pag* 3
NO. PATH
AUTHOR
RECIPIENT
TITLX/DBBCRIPTIOH
PAQB8
26 08/00/94 Geraghty &
Miller, Inc.
27 08/00/94 Geraghty &
Miller, Inc.
28 08/00/94 Geraghty &
Miller, Inc.
29 08/00/94 Geraghty &
Miller, Inc.
30 08/00/94 G«raghty &
Miller, Inc.
31 08/00/94 Geraghty &
Miller, Inc.
32 08/00/95 U.S. EPA
33
05/28/97
34
06/00/97
Mankowski, M.,
U.S. EPA and
B. Treadway,
Ohio EPA
Geraghty 6
Miller, Inc.
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
Public
Metcalf, T.,
Allied-Signal.
Inc.
U.S. EPA
Remedial Investigation 234
Report: Volume 4
(Appendices A-C)
Remedial Investigation 443
Report: Volume 5
(Appendices C-F)
Remedial Investigation 433
Report: Volume 6
(Appendices G-H)
Remedial Investigation 407
Report: Volume 7
(Appendices I-L)
Remedial Investigation 421
Report: Volume 8
(Appendices M-O)
Remedial Investigation 765
Report: Volume 9
(Appendices P-v)
Fact Sheet: Remedial 6
Investigation Completed
at the South Point Plant
Superfund Site
Letter re: U.S. EPA'a 4
Approval of the South
Point Feasibility Study
w/Attached Revised Health
Based Goal Tables to be
Added as an Addendum to
the PS
Feasibility Study 570
(FINAL)
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