EPA/ROD/R03-95/204
                                    1995
EPA Superfund
     Record of Decision:
     RESIN DISPOSAL
     EPA ID: PAD063766828
     OU02
     JEFFERSON BOROUGH, PA
     09/29/1995

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Text:

                         RECORD OF DECISION
                        RESIN DISPOSAL SITE

                             DECLARATION

SITE NAME AND LOCATION

Resin Disposal Site
Operable Unit #2
Jefferson Borough
Allegheny County, Pennsylvania

STATEMENT OF BASIS AND PURPOSE

This decision document presents the selected remedial action for Operable Unit #2  (OU2) at the Resin Disposal
Site (Site) in Jefferson Borough, Allegheny County, Pennsylvania, developed and chosen in accordance with the
Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended, (CERCLA) 42 U.S.C.
§§ 9601 et seg. and to the extent practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan  (NCP),  40 C.F.R. Part 300.  This decision is based on the
Administrative Record file for this site.

The Commonwealth of Pennsylvania, Department of Environmental Protection (PADEP)  has concurred with the
Record of Decision  (ROD).

ASSESSMENT OF THE SITE

After consideration of the existing and future risks posed to human health and the environment, EPA's
selected remedy for the ground water portion of this Site is No Further Action, with monitoring.  Based on
information collected to date, the EPA has determined that no additional remedial actions, other than those
already selected as part of the Operable Unit 1 (OU1) source control remedy for the Site, are reguired to
ensure protection of human health and the environment.  All the components of the OU1 remedy should be
completed in the next twelve months.  The Site will then gualify for inclusion in the "sites awaiting
deletion" subcategory of the Construction Completion category of the National Priorities List.

DESCRIPTION OF THE REMEDY

This Operable Unit is the second and final operable unit for the Site and it addresses ground water
contamination.  The selected alternative for the ground water at the Site is no further action with periodic
monitoring of offsite ground water.  This offsite monitoring will include sampling of the offsite monitoring
wells,  as well as monitoring the seeps and residential wells near the Site.  The onsite ground water will be
monitored pursuant to the Remedial Action selected in the ROD for the first Operable Unit.

After the source control remedy is completed, the onsite and offsite ground water will both be periodically
monitored to ensure that human health and the environment are being protected.

STATUTORY DETERMINATIONS

Pursuant to duly delegated authority, I hereby determine, pursuant to Section 106 of CERCLA,  42 U.S.C. §
9606, that the selected remedy is protective of human health and the environment.  Although no further
remedial action will be taken, ground water guality at and in the vicinity of the Site will be reviewed
within five years in accordance with Section 121(c) of CERCLA, 42 U.S.C. § 9621 (c) to ensure that human
health and the environment continue to be adeguately protected.

                                     
Tom Voltaggio                                         Date
Hazardous Waste Div. Director
Region III

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                         RECORD OF DECISION
                          TABLE OF CONTENTS

                                                                 Page

I       SITE NAME, DESCRIPTION, AND LOCATION                        1

        A.      Site Name and Location                              1
        B.      Site History and Enforcement Activities             1
        C.      Highlights of Community Participation               6
        D.      Scope and Role of Operable Units                    6
        E.      Site Characteristics                                7
        F.      Nature and Extent of Contamination                  8

II      SUMMARY OF SITE RISKS                                       9

III     DESCRIPTION OF ALTERNATIVES                                13

IV      COMPARATIVE ANALYSIS OF ALTERNATIVES                       15

V       DESCRIPTION OF THE SELECTED REMEDY                         20

VI      STATUTORY DETERMINATIONS                                   20

VII     RESPONSIVENESS SUMMARY                                     23

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                         RECORD OF DECISION

                         RESIN DISPOSAL SITE

                          DECISION SUMMARY


I.      SITE NAME, DESCRIPTION, AND LOCATION


A.      Site Name and Location

        The Site is located about one half mile west of the town of West Elizabeth in Jefferson Borough,
Allegheny County, Pennsylvania and comprises approximately 26 acres (Figure 1).  West Elizabeth is a mixed
commercial, industrial and residential area with a stable population.   According to U.S. Census Bureau
1990 records, the population within a one-mile radius of the Site is 1,819.  The Site operated as a landfill
between 1950 and 1964. The landfill is located in the head of a narrow valley on the site of a former coal
mine and comprises slightly less than 2 of the 26 acres.

        The Site is surrounded by a suburban residential area to the north and west and by undeveloped
property to the south and east. A trailer park and several residential homes are located approximately
1/4-mile southeast and downslope of the Site.  The topography of the area is characterized as relatively
level highland, with deeply eroded stream valleys.  Coal was strip- and deep-mined from the nearby stream
valley prior to 1950 in the area surrounding the Site.

        Although guantities of ground water are available for domestic use in certain areas, the vast
majority of the residents in the Site area are connected to a public water supply.  The Monongahela River is
located about 1/2 mile from the Site, and is the water source for the public water system in the
neighborhood. However, eight residential wells were identified within approximately one mile of the Site.
Most of these residents are also hooked up to the public water supply, and use their private well as an
alternative water supply for activities like washing their cars or watering their lawns.

B.  Site History and Enforcement Activities

        Between 1950 and 1964, prior to the enactment of the Resource Conservation and Recovery Act, as
amended (RCRA), 42 U.S.C. §§ 6901 et seg.,  the Pennsylvania Industrial Chemical Corporation  (PICCO) Plant
generated and deposited an estimated 85,000 tons of production wastes into the onsite landfill.  As a
result of these activities, the Site is also known as the PICCO Resin Landfill.   The wastes consisted mainly
of clay poly cakes and dechlor cakes, which are composed of petroleum and coal-derived chemicals mixed with
clay.  Total petroleum hydrocarbons compose approximately 6% of the waste.  The waste was deposited in the
landfill by dumping it down a topographic chute above the landfill as a wet viscous sludge.  The waste was
contained within the landfill behind two earthern dikes (Figure 2).  No historical
records exist of the actual types or guantities of waste deposited in the landfill.



        Prior to 1950, the original coal was strip-mined and deep-mined on the site property.  The deep
mining was done through a process known as room and pillar mining which resulted in mine voids throughout the
Site.  At the location of the landfill, approximately 20 feet of waste was deposited in place of the
mined coal.

        Hercules Incorporated  (Hercules) purchased the business and facilities,  which includes the landfill
property,  from PICCO in 1973.  Between 1980 and 1984, a series of field investigations were conducted to
provide information on ground water conditions in the coal formation,  the deep bedrock formation, and the
extent of contaminated soils just downgradient of the landfill.  These field investigations were conducted
for Hercules and were performed by Roy F. Weston, Inc.  (Weston) and Murray Associates. The data from these
early investigations indicated that contaminants had migrated beyond the buried waste in the landfill and
could be found in ground water in the Pittsburgh Coal Formation and in downslope soils and perched ground
water.  As a result of these investigations, Weston recommended that Hercules install a leachate collection
trench below the lower landfill dike to collect leachate and ground water  (See Figure 3).  This trench was
installed with the initial oil/water separator in 1983.  Liguids collected in the trench are now directed to
an upgraded oil/water separator which was installed in June of 1995. The oil is presently burned as fuel at
the Hercu]es Jefferson Plant boiler, and the water is discharged to the Jefferson Borough Sanitary Sewer
System which drains to the West Elizabeth Sanitary Authority (WESA) for treatment.

        A Site Investigation was completed in April 1982,  and the Site received a Hazard Ranking Score of
37.69 in December 1982. The Site was proposed for the National priority List (NPL) in December 1982 and was

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placed on the NPL in September 1983.  On November 2, 1987, Hercules entered into a Consent Order and
Agreement with the Pennsylvania Department of Environmental Resources  (PADER),  which was renamed the
Pennsylvania Department of Environment Protection (PADEP) on July 1, 1995, to conduct a Remedial
Investigation/Feasibility Study (RI/FS) at the Site. The Remedial Investigation  (RI) work plan was approved
by PADER and EPA in February 1988, and work began on March 17, 1988.  The purpose of the initial RI/FS was to
characterize the Site for potential remediation.  This included an extensive study of the
extent of contamination of the soils, ground water,  and surface water associated with the landfill and
related activities onsite. A final RI for OU1 was submitted to PADER and EPA in March 1991, and the RI and
the FS were eventually finalized in June, 1991.



        A Record of Decision for OU1 was signed on June 28, 1991. Hercules signed a Consent Decree to perform
the RD/RA in February, 1992.  The Remedial Design is almost finished at this time and the Remedial Action for
the landfill cap should begin in the next month or two.  A Consent Order to perform an RI/FS for OU2 was
signed by Hercules in June, 1992.   The Final RI Report for OU2 was submitted in August, 1994, and the Final
FS Report was submitted in April,  1995.  EPA developed the Draft and Final Risk Assessment for the second
operable unit at this Site.

C.      Highlights of Community Participation

        EPA performed the activities set forth in Sections 113(k) and 117(a) of CERCLA, 42 U.S.C. § 9613(k)
and 9617 (e) .  The RI/FS and Proposed Plan for the Resin Disposal Site were released to the public on April
22, 1995.   These documents were made available to the public in the local information and
administrative record repository at the Jefferson Borough Municipal Building, 925 Old Clairton Road,
Jefferson Borough, Pennsylvania, and also at the EPA Region III office.  The notice of availability for these
documents was published in the McKeesport Daily News on April 22, 1995.  A public comment period
was held from April 22, 1995, through May 22, 1995.   This comment period was extended to June 22, 1995 as a
result of an extension reguest by a private citizen.  Additionally, a public meeting was held on May 10,
1995, at the Jefferson Borough Municipal Building.  At this meeting, representatives from EPA answered
guestions about the Site and the remedial alternatives under consideration for OU2.   Response to the comments
received during this period are included in the Responsiveness Summary, which is part of this Record of
Decision.   This decision document presents the selected remedial action for the Site chosen in accordance
with CERCLA and the NCP.  The decision for this Site is based on the Administrative Record file.

D.      Scope and Role of Operable Units

        EPA has chosen to categorize the Site into two operable units.

        Operable Unit One

        Operable Unit One  (OU1), authorized by a ROD signed on June 29, 1991, addressed remediation of the
waste material in the landfill, the adjacent contaminated soils and non-agueous floating product present in
the subsurface Pittsburgh Coal nine voids.  The remedy for OU1 included replacing the onsite
oil/water separator with an upgraded model.  The oil/water separator replacement has been completed at this
time.  Other important components of the remedy for OU1 are installation of a multilayer cap for the
landfill,  upgrading of the lower landfill dike to increase its stability, installation of drainage controls
around the landfill, installation of a skimmer well network, installation of additional fencing around the
Site, and placing deed restrictions on the Site's property.  The remedial design for the remaining portions
of the OU1 remedy is still under review by EPA and PADEP.  The Remedial Design will be finalized soon, and
the Remedial Action will begin following EPA approval of the final Remedial Design.   All the remaining
portions of the OU1 remedy will be completed in approximately 8-12 months.

        Operable Unit Two

        Operable Unit Two  (OU2) addresses any ground water remediation reguired for the ground water beneath,
or in the vicinity, of the Site.  OU2 includes the ground water in the Pittsburgh Coal mine voids as well as
the deeper bedrock formation.  This portion of the Site was not addressed in the ROD for OU1.  Additional
information about the ground water at the Site was obtained in the focused Remedial Investigation for OU2.

E.      Site Characteristics

        The Site is located on a 26-acre parcel of land of which the landfill itself covers approximately
2-acres and is located on a former coal strip mine at the head of a narrow valley.  The landfill is located
in the middle of the Site property.  The unnamed stream, which originates onsite, runs through the Site from
the northeast and flows downslope to the southeast,  ultimately discharging into the Monongahela River

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approximately 1/2-mile from the Site boundary.  No parks, recreation areas, wildlife refuges, historic and/or
archeological sites, or wild and scenic rivers are located on or adjacent to the Site.
No endangered species of plants or animals were found to exist onsite.

        Major sources of ground water in the area are alluvial valley fill aquifers in the large river
valleys; however, ground water within the Site area is limited to storage in fractured bedrock, the
Pittsburgh Coal mine voids, and as perched ground water in the unconsolidated soils just downhill from the
landfill.  Ground water yield is low in the bedrock due to the generally unfractured condition of the deep
bedrock beneath the Site.  At lower altitudes in the surrounding neighborhood,  which is about a mile or more
downgradient of the Site, there are areas of fractured bedrock where sufficient ground water is present in
the deep bedrock aguifer to provide a drinking water source.

        Although the coal seam also contains ground water, it is not likely to be used as a potable source
because of its undesirable properties,  such as the high concentrations of iron, aluminum, manganese and
chromium.   This ground water also contains high levels of sulphur compounds, and dissolved solids.   The
proximity of public water lines also reduces the chance of anyone using the coal seam water as a drinking
supply in the foreseeable future.   The flow of ground water in the unconsolidated soils downgradient from
the Site generally parallels the surface topography.   The direction of ground water flow is to the west
from the Site.   Properties east of the Site are considered upgradient.   Ground water beneath the Site flows
away from, and not towards, an upgradient property.   Although the communities surrounding the Site are
connected to a public water supply, some homes still use wells for their water supply.   These wells are
located in the deep bedrock aguifer.   No residents currently drink the ground water from the Pittsburgh Coal
formation.

F.      Nature and Extent of Contamination

        Hercules submitted the Focused Remedial Investigation (FRI)  report to EPA for OU2 in August 1994.
The investigation was considered focused in that only the ground water aspects of the Site were studied.
The FRI report presented the results and interpretation of an infiltration evaluation, an ecological
habitat assessment, ground water monitoring well sampling, seep sampling, and residential well sampling done
to further characterize the extent of OU2 contamination.   A total of 11 monitoring wells, eight residential
wells, and nine seeps were sampled as part of this FRI.   Benzene was present in TW-14, an
onsite monitoring well, at a level above the Safe Drinking Water Act federal maximum contaminant level  (MCL)
of 5 parts per billion.   There were no contaminants above any MCL in any of the offsite monitoring wells.

        The levels of contamination in the onsite monitoring wells were significantly lower in the OU2
sampling than in the same wells during the OU1 sampling.  This decrease in contamination levels, which was
generally about a 20% decrease from OU1 sampling to OU2 sampling, suggests that natural attenuation of
site-related organic constituents in the ground water within the Pittsburgh Coal mine voids may be occurring
through various mechanisms.  These mechanisms include adsorption of organic compounds within the saturated
coal, natural biodegradation, and even volatilization in the mine voids.

        During the OU2 sampling, no site-related contaminants were found in any of the downgradient seep
water samples.  Ground water from the onsite underground mines discharges at seeps at the outcrop of the
Pittsburgh Coal above Lobbs Run  (see Figure 1).  There is no current impact of the leachate from the landfill
to the seeps.  The deep bedrock below the Pittsburgh Coal seam is used as a drinking water supply by
residents located about one mile downgradient of the Site.  The residential wells are even further
downgradient than the Lobbs Run seeps and draw water from the bedrock rather than the coal seam.  No
site-related compounds have ever been detected in any of the residential wells near the Site.

        On the basis of the results from the FRI, the EPA prepared a draft risk assessment (RA) in August
1994 to evaluate human-health risks associated with potential exposure to OU2 contamination.    A Final RA was
prepared by EPA in December, 1994 after incorporating comments on the Draft RA by PADER and Hercules.   By
using information from the FRI and the RA, Hercules prepared a Focused Feasibility Study  (FFS) describing a
number of alternatives and their benefits and costs.

        The primary contaminants of concern are organic compounds which comprise approximately 5% of the
waste volume and include: benzene, naphthalene, toluene, and total xylenes.   The remainder of the landfill
waste consists mainly of water, clay, lime, zinc salts, and other solids.   The wastes in the landfill are
presently covered by four to ten feet of native soils.   The waste cannot be seen or touched from the ground
surface because of this soil cover.

        II.     SUMMARY OF SITE RISKS

        In this focused risk assessment, the hazards posed by chemicals detected during the Remedial
Investigation (RI) for OU2 were evaluated.  The OU2 RI was designed to characterize the impact, if any, of
the Site on the ground water, as well as nearby seeps and streams.  Site samples were analyzed for

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volatile and semi-volatile organic chemicals.  Metals have not been included in the risk assessment because
of a determination made during OU1 that inorganics did not appear to be site-related.  However,  a background
well (TW-12) in the Pittsburgh Coal formation had levels of metals exceeding drinking water
standards, including the maximum contaminant level (MCL) for chromium and secondary maximum contaminant
levels  (SMCL) for aluminum, iron and manganese.  Although these high levels of metals are not site-related,
they are characteristic of ground water in coal seams.  The ground water obtained in this
background well is from a mined-out section of Pittsburgh Coal and is an area affects by acid mine drainage.
Ground water in coal seams is considered less desirable than other aquifers because it typically contains
naturally high levels of dissolved solids, metals and sulfur compounds.

        Sediment, ground water and surface water was considered the media of potential concern with regard to
quantitative risk assessment.  All three of these media were previously sampled and assessed in the OU1 risk
assessment.  Potential risks may exist when there are hazardous chemicals present in a media, such as
the ground water, and receptors which may have access to those chemicals through an exposure pathway.

Contaminants of Potential Concern

        The data from the RI were examined in order to determine chemicals of potential concern (COPCs).
COPCs are defined as those substances that are potentially site-related and whose data are of sufficient
quality for use in the risk assessment.  The following substances were considered COPCs for OU2 at this Site:

        - Benzene
        - Benzoic(a)pyrene
        - Ethylbenzene
        - 2-methylnaphthalene
        - 4-methylphenol
        - Naphthalene
        - Toluene
        - Xylenes

        The concentrations of the COPCs used for the risk assessment were the maximum positive concentration
for each contaminant or the 95% upper confidence limit on the mean (average concentration) for log-normal
distributions,  whichever was lower. The actual concentration used in the risk assessment for each COPC is
shown in Table 1.

        Exposure Assessment

        The Resin Disposal Site was evaluated with respect to physical characteristics, current and future
land and water uses, and exposed populations to identify potential exposure pathways. Several factors
determine what receptors may be exposed to the chemicals of concern at a particular site.  At this Site,  the
decision was made to use the most conservative receptor, a future resident who spends some years of both
childhood and adulthood in the area,  for exposure scenarios.  For a Site in a residential area,  it is
expected that residents could be exposed to surface water, sediments and residential well ground water.  The
site-related chemicals in the surface water and sediments were of sufficiently low concentrations that they
were not expected to be associated with any adverse human health effects.  No site-related compounds at all
were found in any of the eight residential wells sampled.  Ground water as measured by monitoring wells was
also treated as a potential source of exposure in the risk assessment.  The risk assessment assumed that
potable wells would be drilled in the Pittsburgh Coal formation in the future.  This is an important
assumption because a future resident who is connected to the public water supply is not exposed to the ground
water in this manner.

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Table 1

Summary of Representative Concentrations of
Contaminants of Potential Concern  (COPCs)
Resin Disposal OU2

Ground Water Monitoring Wells

Chemical                             Concentration                      Rationale
                                         (MG/L)

Benzene                                  0.0152                            UCL
Ethylbenzene                             0.134                             UCL
Naphthalene                              6.0                               MAX
2-methylnaphthalene                      0.72                              MAX
4-methylphenol                           0.172                             UCL
Toluene                                  0.063                             UCL
Xylenes                                  4.4                               MAX

Seep Sediment - Seep #10

Chemical                             Concentration                      Rationale
                                         (MG/KG)

Benzo(a)pyrene                           0.33                              MAX

UCL - The 95% Upper Confidence Limit on the mean or average
concentration for log-normal distributions.

MAX - The maximum positive concentration (MAX) was used in the
Risk Assessment for small sample sizes or where UCL > MAX.

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        Toxicity Assessment

        The relationship between the extent of exposure to a contaminant and the potential for adverse
effects was evaluated during the toxicity assessment process.  Cancer potency factors (CPFs)  also known as
slope factors, were identified for potential carcinogenic contaminants, and reference doses (RfDs)  were
identified for chemicals exhibiting noncarcinogenic effects. The RfDs, which are expressed in units of
mg/kg/day, are estimates of lifetime daily exposure levels for humans, including sensitive individuals, at
which no adverse health effects are noted.  Estimated intakes of chemicals from environmental media
(e.g., the amount of a chemical ingested from contaminated drinking water) are compared to the RfD.  The RfDs
are derived from human epidemiological studies or animal studies to which uncertainty factors have been
applied (e.g., to account for the use of animal data to predict effects on humans).   These
uncertainty factors help ensure that the RfDs will not under-estimate the potential for adverse
noncarcinogenic effects to occur in humans.

        Excess lifetime cancer risks for the Site were determined by multiplying the daily intake of
chemicals from environmental media by the CPFs.  These risks are probabilities expressed in scientific
notation  (i.e., 1E-6).   An excess lifetime cancer risk of 1E-6 indicates that an individual has a one in a
million chance of developing cancer as a result of site-related exposure to a carcinogen over a 70-year
lifetime.   The U.S. EPA recommended upper bound for lifetime cancer risks is between 1E-4 and 1E-6.

        Risk Characterization

        The most significant exposure pathway, in terms of impacting human health,  was to a future resident
via ingestion of contaminated ground water.  The total cancer risk at the Site was approximately 2E-5, which
is based on a future resident drinking the water from a contaminated onsite well.  The risk assessment for
OU1, which was done in 1991, included an analysis for this same exposure scenario,  and at that the the total
cancer risk was 7E-4.   This cancer risk is due primarily to the elevated levels of benzene present in ground
water in the onsite monitoring wells.  Benzene was present in TW-14, an onsite
monitoring well, at a level above the Safe Drinking Water Act federal maximum contaminant level (MCL) of 5
parts per billion. There ware no contaminants above any MCL in any of the offsite monitoring wells.

     Potential concern for noncarcinogenic effects of a single contaminant in a single medium is expressed as
the hazard guotient (HQ) (i.e., the ratio of the estimated intake derived from the contaminant concentration
in a given medium to the contaminant's reference dose).  The HQs for all contaminants in a
medium are added to obtain the Hazard Index (HI).  The HI provides a reference point for gauging the
significance of multiple contaminant exposures within a single medium or across media.  A HI less than or
egual to 1 indicates that there is no significant risk of adverse health effects.  For potential future
residents exposed to the representative concentrations of the COPCs in the monitoring wells,  the HI for an
adult was calculated to be 14 and the HI for a child was 31.  This HI is primarily caused by the naphthalene
and methylnaphthalene in the monitoring wells.  In the risk assessment for OU1, the HI calculations for both
a child and an adult were over 300.  The non-carcinogenic effects of the Site have dropped by an order of
magnitude since the initial Risk Assessment.

        There is no apparent risk of noncarcinogenic health effects posed to the trespasser or to the current
residents in the neighborhood.  The total chronic and short-term hazard indices that were calculated for
these potential receptors were less than one.   Although it is currently not used at a potable source, the
non-cancer health risk is based on potential future use of the water from the Pittsburgh coal seam, which
could be from a future resident drilling a new well in the immediate vicinity of the Site.  Although this
scenario is theoretically possible, it is extremely unlikely because the water in the mines is acid mine
drainage and is generally of poor guality  (low pH with high dissolved metals and sulphur).

        Residential wells and seep surface water were not expected to be associated with adverse health
impacts, based on the results of the OU2 sampling.  Risks for OU2 ground water were much lower than in the
OU1 RI mostly due to significantly lower chemical concentrations in OU2 monitoring.   For example,  the
cancer risk at the time of the OU1 ROD was calculated to be 7E-4, which is significantly higher than the 2E-5
calculated from the OU2 sampling.  Existing residential wells and seep surface water did not contain any
COPCs and therefore were not associated with any adverse human health effects.

III.    DESCRIPTION OF ALTERNATIVES

        A number of remedial alternatives were developed with the goal of further reducing the risk to human
health and the environment from the Site.  The following sections briefly summarize each of these
alternatives.  The time to implement each alternative is the time of actual remediation, it does not
include the time reguired to design the remedy.

        In the FFS for OU2 at this Site, a screening of engineering technologies applicable to remediating
the contaminated media was completed.  A full range of remedial technologies and corresponding process

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options were identified in be FFS.   The technologies were screened according to their effectiveness and
implementability.  Those technologies determined to be most applicable were then developed into the three
remedial alternatives described below.

        The following remedial alternatives are numbered to correspond to the alternatives in the FS report:

        Alternative 1:  No Action
        Alternative 2:  No Further Action With Offsite Monitoring
        Alternative 3:  Ground Water Extraction & Treatment

        The Capital Cost of each alternative is listed, along with the annual Operation and Maintenance (0 &
M) Cost, the total Present Worth and the number of months it would take to implement the alternative.

        Alternative 1:  No Action

        Capital Cost:        $0
        Annual 0 & M:        $0
        Present Worth:       $0
        Months to Implement:  0

        The NCP regulations reguire that the "no action" alternative be evaluated at every NPL site to
establish a baseline for comparison.  Under this alternative, EPA would take no further action, other than
the actions which are part of the OU1 source control remedy, to prevent exposure to the contaminated onsite
ground water or to reduce risk at the Site.  EPA would review the site every five years to assure continued
protection of human health and the environment.

        Alternative 2:  No Further Action With Offsite Monitoring

        Capital Cost:    $ 30,000
        Annual 0 & M:    $ 10,000
        Present Worth:   $308,000
        Months to Implement:  3 months

        This alternative would involve no further remedial action, for the ground water at the Site, other
than monitoring the offsite ground water on a guarterly basis for the next three years, and semi-annually for
the balance of thirty years. Offsite monitoring walls, seeps and nearby residential wells would be sampled as
part of this long-term monitoring program. Monitoring of the bedrock aguifer near the downgradient
residential wells will be reguired, and this monitoring may include installation of new bedrock wells.  An
offsite monitoring work plan will be developed which will describe the exact monitoring points to be included
in the offsite monitoring program.   This offsite monitoring is in addition to the onsite monitoring which is
a component of the OU1 remedy.  EPA would analyze all of this monitoring data every five years to assure
continued protection of human health and the environment.

        Alternative 3:  Ground Water Extraction & Treatment

        Capital Cost:        $3,900,000
        Annual 0 & M:          $594,000
        Present Worth:      $13,032,000
        Months to Implement:  24 to 36 months

        Under this alternative, two lines of closely spaced recovery wells would be installed downgradient of
the landfill.  The ground water extraction wells would be constructed in the Pittsburgh Coal water-bearing
zone.  These two lines of ground water extraction wells would be located to intercept dissolved-phase ground
water contaminants at the Site property boundary and to mitigate offsite contaminant migration.  The combined
ground water flow rate from the two rows of extraction wells is
estimated to be in the range of 50 to 100 gallons per minute, and would probably vary on a seasonal basis.
Ground water extracted from the recovery wells will be conveyed via transmission lines to a treatment system.
The treated effluent would be discharged to the unnamed stream that runs across a portion of the Site.  An
effluent sampling and flow monitoring station would be provided for the treated effluent discharge.

IV.     COMPARATIVE ANALYSIS OF ALTERNATIVES

        The EPA evaluated each of the remedial alternatives developed for the Site with respect to the nine
criteria set forth in the NCP.  The following sections present a brief discussion of each of the evaluation
criteria and a comparative analysis of each of the remedial alternatives based on the nine
evaluation criteria.

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        The Superfund statute, and the implementing regulations, found in the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP),  40 C.F.R. Section 300, reguire that the alternative chosen to
clean up a hazardous waste site meet several criteria.  The alternative must protect human health and
the environment, be cost effective, and meet the reguirements of environmental regulations.  Permanent
solutions to contamination problems should be developed, whenever possible.  These solutions should reduce
the volume, toxicity, or mobility of the contaminants wherever practicable.  Emphasis is also placed on
treating the wastes at the Site, whenever this is possible, and on applying innovative technologies to clean
up the contaminants.

        Based on current information, the EPA anticipates that Alternative 2 will be protective of human
health and the environment.  EPA believes that the Preferred Alternative provides the best balance of
trade-offs among the alternatives with respect to the nine criteria (See Table 2) that EPA uses to
evaluate alternatives.  This section profiles the performance of the Preferred Alternative against the nine
criteria noting how it compares to the other remedial alternatives under consideration.

Overall Protection of Human Health and the Environment

        This criterion addresses whether a remedial alternative will adeguately protect human health and the
environment.  The evaluation criteria should consider:  the reduction of risk; any unacceptable impacts;
control of hazards  (i.e., toxicity, mobility); and minimization of short-term impacts.

        Under Alternative 1, the overall protection of human health and the environment may not be achieved
at some time in the future.  The RA showed no risks associated with current use of the Site.  The deed
restrictions, which are part of the OU1 remedy, will prevent future residential use of the Site.  There is
concern that the onsite ground water contamination could move offsite at some point in the future and
subseguently contaminate a nearby residential well.  Alternative 2 provides an additional level of control
because the monitoring will provide offsite sampling data in future years.  Alternative 2 provides for
greater overall protection of human health and the environment than Alternative 1 because the monitoring
program will detect any offsite ground water problem, if one ever develops, before the contamination reaches
a residential well.  Alternative 3 has the added protection provided by actively pumping the onsite ground
water and treating it at the surface.  In comparing Alternatives 2 and 3, the additional cost of Alternative
3 is substantial, approximately $13 million,  and the additional protection provided by pumping and treating
the ground water is minimal.  The aguifer is not used presently as a drinking water source, nor is it likely
to be used in the future in that manner.  Alternative 2
provides good overall protection of human health and the environment at a low cost.

Compliance With ARARS

        This criterion addresses whether or not a remedy will meet all of the applicable or relevant and
appropriate reguirements (ARARs) set forth by State and Federal environmental laws and/or provide grounds for
invoking a waiver.  Three categories of ARARs are considered:  chemical specific, action specific and
location specific.  All three of the alternatives would meet all of the ARARs identified in the Focused
Feasibility Study for that particular alternative.

        There are several significant ARARs which are applicable or relevant and appropriate only to
Alternative 3 because it is the only alternative that involves treatment of contaminated ground water.  The
treated ground water would have to meet all the appropriate cleanup standards in the Clean Water Act and the
Pennsylvania Clean Streams Act before it could be discharged to a receiving stream.  These are
chemical-specific ARARs, and the standards would be difficult to achieve at this Site.  The Pittsburgh Coal
has naturally high levels of chromium, aluminum, iron and manganese.  For example, a background well in the
Pittsburgh Coal formation exceeded the MCL for chromium by an order of magnitude.  All of these individual
standards must be met by the treatment system whether the contaminant is site-related or naturally occurring.

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                               Table 2

                   ALTERNATIVE EVALUATION CRITERIA

Overall Protection of Human Health and Environment - Addresses whether a remedy provides adequate protection
and describes how risks posed through each pathway are eliminated, reduced or controlled through treatment,
engineering controls or institutional controls.

Compliance with ARARs - Refers to whether a remedy will meet all of the applicable or relevant and
appropriate requirements (ARARs)  of federal and state environmental statutes and/or provides grounds for
invoking a waiver.

Long-term Effectiveness and Permanence - The ability of a remedy to maintain reliable protection of human
health and the environment over time, once the cleanup standards have been met.

Reduction of Toxicity, Mobility,  or Volume through Treatment - Relates to the anticipated performance of the
treatment technologies with respect to these criteria.

Short-term Effectiveness - Refers to the period of time needed to achieve protection, and any adverse impacts
on human health and the environment that may be posed during the construction and implementation period until
cleanup standards are achieved.

Implementability - The technical and administrative feasibility of a remedy, including the availability of
materials and services needed to implement a particular option.

Cost - The following costs are evaluated for each alternative: estimated capital, operation and maintenance
and net present worth.

Support Agency Acceptance - This indicates whether, bases on its review of the RI/FS and the Proposed Plan,
the State concurs with, opposes,  or has no comment on the selected alternative.

Community Acceptance - is described in the Responsiveness Summary section of the ROD following a review of
the public meeting transcript and the public comments received during the public comment period.

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        The Commonwealth has identified The Land Recycling and Environmental Remediation Standards Act, the
Act of May 19, 1995, P.L. 4, No. 1995-2, 35 P.S. §§ 6026.101 et seq.,  ("the Act") as an ARAR in this case.
However, EPA has reviewed the Act and concluded that the Act in not an ARAR in the present case.  EPA will
make an independent review of the ARAR when it is identified by PADEP in the future in connection with the
selection of remedies for other sites and operable units.

Short-term Effectiveness

        This criterion refers to the length of time required to achieve protection of human health and the
environment, and to prevent any adverse impacts posed during the implementation of the remedial alternative.
Alternatives 1 and 2 do not involve construction or implementation of further remedial activities atthe Site,
so no short term adverse impacts will be created by either of these alternatives.  Alternative 2 could be
easily implemented, and requires only minor sampling activities that can be done in a short period of time.
Adding new offsite monitoring wells to the monitoring program is also a possibility. Alternative 2 has good
short-term effectiveness because it can be done so rapidly.  Alternative 3 has the least short-term
effectiveness of all the alternatives.  Installation of the
extraction well network would involve earth disturbance, extensive excavation, and tree clearing for the
pilot boring programs.  This construction would have a negative impact in residential areas, mainly because
of the additional truck traffic.  The treatment system would also be difficult to install.

Long-Term Effectiveness and Permanence

        This criterion refers to the ability of a remedy to maintain reliable protection of human health and
the environment over time once the cleanup standards have been met.  Under Alternative 1, changes in ground
water quality over time would result from natural processes  (sorption, weathering, biodegradation) as well as
from the remedial action performed for OU1 (landfill capping, drainage controls, etc.).  Alternative 2 would
involve periodic sampling over a 30-year period.  Any changes in concentration over time would be detected,
and trends in the data could be analyzed.  In Alternative 3, the lines of capture wells could probably
achieve some interception and recovery of contaminants in the Pittsburgh Coal seam.

Reduction of Toxicity, Mobility and Volume

        This criterion addresses the statutory preference for selecting a remedial alternative that
permanently reduces the toxicity, mobility, or volume of the hazardous waste through treatment.  The Remedial
Action for OU1 will have a greater impact on the reduction of toxicity,  mobility and volume of waste than any
of the three alternatives described in the FFS for OU2.  The OU1 activities will reduce landfill seepage
volume, and mobility, and will also reduce downgradient contaminant levels. Alternative 3 does involve ground
water treatment which should slightly reduce the mobility and volume of contaminants in the Pittsburgh Coal
ground water.  Due to the inherent high levels of inorganics, such as chromium or iron, in this ground water,
restoration of this water to bring it up to public water standards would be difficult and expensive.

Implementability

        This criterion describes the technical and administrative feasibility of a remedial alternative,
including the availability of materials and services needed to implement the selected solution.  All three
alternatives involve proven, readily implementable technologies:  however, Alternative 3 would involve
more construction and operation concerns than either Alternative 1 or Alternative 2.  Alternative 3 involves
a boring well location program followed by installation of numerous extraction wells.  Hydraulic capacity of
the unnamed stream to handle treated water would have to be carefully evaluated in the design
of the water treatment system.  Alternative 3 would be the most difficult alternative to implement.

Costs

        This criterion addresses the capital cost for materials, equipment, etc.  and the operation and
maintenance  (O&M) costs. Assuming a net present worth (NPW) including 30 years of O&M costs.  Alternative 3
is by far the most expensive option with a present net worth of approximately $13,000,000.  Alternative 2 is
much less expensive, because sampling is relatively inexpensive in comparison to treatment.  Alternative 1
has absolutely no cost.

Support Agency Acceptance

        This criterion indicates whether, based on its review of the Remedial Investigation (RI), Feasibility
Study  (FS),  and the Proposed Plan, the State concurs with, opposes, or has no comment
on the preferred alternative.  PADEP has concurred with the selection of Alternative 2 for Operable Unit #2
at this Site.  The concurrence letter from PADEP is attached.  The State also concurred with the remedy
selection for Operable Unit #1 in June, 1991.

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Community Acceptance

        This criterion assesses the public comments received on the RI, FS, and the Proposed Plan.  Community
interest is moderate at the Site.  A public meeting was held on May 10, 1995,  at the
Jefferson Borough Municipal Building.  This meeting was attended by about fifty people and public involvement
was good.  There were numerous guestions about the various aspects of the remedy
for OU1, particularly about the operation of the oil/water separator.  The public did have some guestions and
comments about the ground water at the Site.  Some members of the community are in favor of Alternative 3,
and feel that the high cost of the treatment alternative is warranted.  Several of these individuals felt
that a treatment remedy like Alternative 3 could be completed for much less than the $13 million cost
calculated in the Feasibility Study and described in the Proposed Plan.  Most of the citizens at the meeting
were guite satisfied with Alternative 2, and felt it was the appropriate remedy for OU2.
The Responsiveness Summary addresses specific comments received during the public comment period.

V.      DESCRIPTION OF THE SELECTED REMEDY

        The selected remedy reguires periodic monitoring of the offsite ground water in the vicinity of the
Site.  This monitoring program will include sampling offsite monitoring wells, seeps and downgradient
residential wells.  The monitoring will occur on a guarterly basis for the first three years, and
semi-annually for the balance of thirty years.  The ingestion of water from a new well drilled into the
Pittsburgh Coal seam is considered unlikely, because a public water supply is readily available to residents
in the area surrounding the Site.  A future well in the deeper bedrock aguifer in the vicinity of the Site is
also unlikely because the bedrock in this area is dry. Periodic monitoring meets the evaluation criteria of
protecting human health and the environment.  Additionally, the source control measures undertaken to address
OU1 is likely to reduce the contamination in the OU2 ground water, and even further reduce the site-related
risks in the future.

        In accordance with CERCLA § 121(d), EPA will review the Site in five years to ensure that changes
have not occurred that would pose a risk to human health or the environment.  During those five years,  a
ground water monitoring program will be implemented and sampling data will be periodically collected and
analyzed. All the data collected during the ground water monitoring program will be evaluated by EPA to make
certain that human health and the environment are being adeguately protected by the selected remedy.  If the
offsite ground water monitoring program reveals levels of contamination above the MCL for any COPC then EPA,
in consultation with PADEP, may amend the ROD or issue an Explanation of Significant Differences  (BSD)  in
accordance with the NCP.

VI.     STATUTORY DETERMINATIONS

        The EPA's primary responsibility at Superfund sites is to implement remedial actions that are
protective of human health and the environment.  Section 121 of CERCLA, 42 U.S.C. § 9621, also establishes
several other statutory reguirements and preferences.  The selected remedy must be cost effective and
utilize a permanent solution to the maximum extent practicable. The selected remedial action must comply with
all applicable or relevant and appropriate reguirements set forth by State and Federal environmental statutes
and regulations, unless a waiver is justified.  Finally, CERCLA sets forth a statutory preference
for remedial actions that permanently reduce the toxicity, mobility, and volume of the site-related wastes.
The following sections discuss how the selected remedy meets the statutory reguirements and preferences set
forth in Section 121 of CERCLA.

Protection of Human Health and the Environment

        The risk assessment identified future exposure to contaminated ground water as the most significant
exposure pathway in terms of its potential impact on human health.  There are no significant health threats
to residents presently living near the Site.  The offsite monitoring will insure that the Site does not ever
present a health risk to future residents even if they decide to drill a private well on a nearby property.
Additionally, implementation of this alternative is not expected to result in any adverse short-term risks or
cross-media impacts.

Compliance With Applicable or Relevant and Appropriate Reguirements

        The selected remedial action will comply with all ARARs.  The ARARs specific to the selected remedy
are presented below. Except where specifically noted, the site specific limitation to the following ARARs
will be identified in the remedial design phase.

         !       Chemical-specific ARARs:

        Safe Drinking Water Act - National Primary Drinking Water Standards (40 CFR Part 141).   Federal
Standards for several chemicals including the MCLs, adopted to protect public drinking water systems.  MCLs

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are enforceable, health-based drinking water standards established under the Safe Drinking Water Act.   These
chemical-specific standards are relevant and appropriate for the ground water monitoring program at this
Site. For example, benzene is a COPC for this operable unit and it has an MCL of 5 parts per billion.
Standards, such as the MCL for benzene, will be considered and used in characterizing human held risks
associated with possible contaminated ground water for public consumption.

        PA Safe Drinking Water Act (35 PS 722.1-721.17 & 25 PA Code Chapter 109)  - State act which
established drinking water standards at least as stringent as Federal Standards.   These chemical-specific
standards are relevant and appropriate for the ground water monitoring at this Site.   These standards  will be
considered and used in characterizing human health risks associated with possible contaminated ground  water
for public consumption.

         !       Location-specific ARARs:

        None

         !       Action-specific ARARs:

        None

Cost Effectiveness

        The selected remedy is cost effective and has been determined to be the best balance between cost and
protection of human health, welfare and the environment.  The selected remedy has excellent short-term
effectiveness proportional to its cost. The estimated capital cost for this alternative is $30,000, with
a net present worth cost including 30 years of operation and maintenance of $308,000.  The selected remedy
provides a level of protection of human health comparable to that provided by the other remedies, but  at a
significantly reduced cost.  Although Alternative 3 may possibly be more effective in the long-term, the
site-related risks are so low that they do not justify the additional capital expenditure.

Utilization of Permanent Solutions to the Maximum Extent Practicable

        The EPA has determined that the selected remedy represents the maximum extent to which permanent
treatment technologies can be utilized in a cost effective manner for the Site.  Of those alternatives that
are protective of human health and the environment and comply with ARARs, the EPA has determined that
the selected remedy provides the best balance in terms of short-term effectiveness; implementability;  cost;
reduction in toxicity, mobility,  and volume; and long-term effectiveness.

        The selected remedy does not offer as high a degree of long-term effectiveness as Alternative  3, the
pump and treat alternative; however it does have good long-term effectiveness. The excess human cancer risk
at the Site has been estimated to be approximately 2 in 100,000 (based on maximum plausible exposure
concentrations) for future resident.   Current residents are not at risk of exposure to carcinogenic
substances.  The Site has a relatively high volume  (85,000 tons) of low toxicity waste.  Due to the
relatively low risk associated with the Site, EPA has determined that the use of more costly treatment
technologies at the Site are not justifiable.

Documentation of Significant Changes

        The preferred alternative originally identified in the Proposed Plan is also the preferred
alternative selected in the ROD.   There have been no significant changes made to the selected remedy in the
time period between the issuance of the Proposed Plan on April 22, 1995 and the signing of the ROD
approximately  five months later.

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                       RESPONSIVENESS SUMMARY
                         RESIN DISPOSAL SITE
                               UNIT #2
                          JEFFERSON BOROUGH
                   ALLEGHENY COUNTY, PENNSYLVANIA
                             JULY, 1995

        The EPA established a public comment period from April 22, 1995 to May 22,  1995 on the Remedial
Investigation and Feasibility Study (RI/FS),  the Proposed Plan which described EPA's preferred alternative
and other site-related information for Operable Unit #2 at the Resin Disposal Site in Jefferson Borough,
Pennsylvania.  This public comment period was extended to June 22, 1995 at the reguest of a private citizen.
The RI/FS and other site-related documents utilized by the EPA to select a preferred alternative are included
in the Site's administrative record file and have been available to the public since the
beginning of the public comment period.  A public meeting was held on May 10, 1995 and approximately 50
people were in attendance.  A total of five written comments were also received during the public comment
period.

        The purpose of this Responsiveness Summary is to summarize significant comments and new data received
during the public meeting or in writing, and to provide EPA'S responses to the comments.

        This responsiveness summary is divided into the following sections:

Section I Overview:  A discussion of the public response to the preferred alternative.

Section II Background of Community Involvement and Concerns: A discussion of the history of community
        interest and concerns raised during remedial planning activities at the Resin Disposal Site.

Section III Summary of Significant Comments Received During the Public Comment Period and Agency
Responses.  A summary of comments and responses categorized by topic.

I.      Overview:

        Comments received from the public suggest that area residents do not object to the selected
alternative.  In general, the residents are concerned that having a Superfund site in their neighborhood may
be having a negative impact on their property values.  In addition, there is some concern that hazardous
substances are being left in place, and may pose a health threat at some time in the future.  EPA has
included periodic sampling of offsite ground water in the selected alternative to address this concern.

II.     Background of Community Involvement and Concerns:

        A public meeting to discuss the RI/FS Work Plan for Operable Unit #1 (OU1)  on August 5, 1987 in the
old Jefferson Borough Municipal Building.  PADER and EPA personnel were both present at the meeting but
public interest was low.  The RI/FS for OU1 began in November, 1987 after Hercules signed a Consent Order
with PADER to do the work.  At the end of that RI/FS, a public meeting was held on May 6, 1991 at the new
Jefferson Borough Municipal Building to discuss the preferred alternative for OU1.  Approximately 30 people
were in attendance and they did express some concerns about the possible human health impacts of the Site.

III.    Summary of Major Comments Received During the Public Comment Period and Agency Responses:

        1.      Extension of the Public Comment Period

        A citizen asked at the public meeting and also in writing for an extension of the public comment
period for an additional thirty days.

EPA Response:  This reguest was granted, and the public comment period was extended to June 22, 1995.

        2.      Moving the Administrative Record File

        The same citizen also reguested at the public meeting that the Administrative Record File be moved to
the public library located within the Jefferson Borough Municipal Building.  The citizen explained that the
public library is open for longer hours than the other offices located within the Municipal Building.

EPA Responses:  This reguest was granted.  The Administrative Record was moved on May llth, the day after the
public meeting. This transfer was also mentioned in the newspaper advertisement describing the extension of
the public comment period.

        3.      Direction of Ground Water Flow

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        Several citizens were concerned about property upgradient,  or east,  of the Site property,  and whether
it was in any way impacted by the ground water flowing beneath the Site.  There was also some confusion about
which direction was considered downgradient from the Site.

EPA Response:  Ground water flow in the Pittsburgh Coal formation is to the west in the vicinity of the Site.
Thus the ground water at the Site flows away from and not towards a property east of the Site.   In the
vicinity of the Site, the Pittsburgh Coal formation dips towards the southwest.  Ground water flow in the
Pittsburgh Coal generally follows the dip of the coal formation. During the RI for OU1, a monitoring well
(TW-15)  was constructed east, or upgradient, of the Site.  Analysis of the samples collected from that
location show no site-related contaminants of any kind.  A property east of the Site is not in any way
impacted by the ground water beneath the Site.

        4.       Ground Water in the Pittsburgh Coal Mine Voids

        A concern was raised by PADER about the lateral flow of ground water in the Pittsburgh Coal Mine
voids since the voids are a potential source of offsite contaminant migration.

EPA Response:  The landfill is located at the head of a valley and the majority of the landfill perimeter is
surrounded by a higher topography.  The landfill acts as a catch basin to collect surface water and rainfall
from the valley. It is clear that surface water and rainfall infiltration are significant
contributors to flow into and through the landfill, and hence a significant contributor to leachate
generation and contaminant migration.  Both of these pathways will be eliminated by components of the OU1
remedy.

        Swale improvements around of the perimeter of the landfill were done in March, 1994 in order to
reduce surface water runon. These swales are shallow trenches dug into the hillside which prevented water
from running down the hill and on to the landfill from higher elevations.  Prior to those improvements, the
Site was yielding approximately 41,000 gallons of flow through the oil/water separator for each inch of
rainfall.  Following the swale improvements, the amount collected at the oil/water separator was reduced to
23,000 gallons per inch of rainfall. This is a 40% reduction merely by improving the swale system around the
perimeter of the Site.  These data clearly support the conclusion that flow from the landfill is greatly
affected by vertical infiltration.  The landfill cap and the infiltration controls, which are components of
the OU1 remedy, will further reduce both the amount of vertical infiltration and the leachate generated by
the landfill.  The amount of leachate collected at the oil/water separator will be significantly lower after
the Remedial Action for OU1 is completed.

        The lateral flow of ground water from the Pittsburgh Coal through the landfill is not a significant
contributor to offsite contaminant migration.  The water in the Lobbs Run seeps, which was sampled as part of
the OU2 RI, does not contain site-related contaminants.  These seeps are where the Pittsburgh Coal ground
water reaches the surface immediately downgradient of the Site. If the Pittsburgh Coal ground water was
contributing to offsite contaminant migration, these seep water samples would have to show site-related
contamination.

        5.       Effectiveness of the Pump and Treat Alternative at this Site

        A guestion was raised about the effectiveness of pumping and treating contaminated ground water in an
area that has been heavily mined.

EPA Response:  A water treatment alternative, such as Alternative 3, would be difficult to install and
operate in a complex hydrogeological setting, such as the Pittsburgh Coal formation at this Site.   It would
be difficult to install recovery wells, and the overall effectiveness of such a system would be guestionable.
High levels of iron, manganese, aluminum and chromium are present in the upgradient background wells in the
Pittsburgh Coal formation.  Due to the inherent contamination in the Pittsburgh
Coal from past mining activities, restoration of this water guality to potable guality would probably never
occur.

        6.       The Trigger for a Remedial Cleanup.

        A comment was submitted by PADEP which raised a concern about the excess cancer risk at this Site,
and felt it was enough to warrant a cleanup.  The excess lifetime cancer risk of a future resident was
estimated in the OU2 Risk Assessment to be 2E-5, which corresponds to 2 excess cancers in a population of
100,000 people.

EPA Response:  The potential future risk for using the ground water is 2E-5.   This falls within the range
that EPA generally considers acceptable for cancer risk, 1E-6 to 1E-4. Additionally, this potential risk is
expected to be further reduced over time, after the OU1 remedy is in place,  and natural attenuation of
chemicals in the ground water occurs.  Most importantly, no one is being exposed to this ground water at the

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present time nor for the foreseeable future.

        The level of cancer risk necessary to trigger action is 1E-4.  A risk of this level or greater is
enough to trigger a remedial action at a Site.  A remedial action which is so triggered can reguire a cleanup
to reduce risks to the 1E-6 level of cancer depending on the Site.  Thus a cleanup can continue
until the 1E-6 risk level is reached.  The cleanup may end however when an MCL is reached,  which for some
chemicals is a 1E-5 risk level.  A cleanup in an industrial setting may end when the 1E-4 risk level is
reached.

        7.      Performance of the Long-Term Monitoring

        PADEP commented about whether EPA or Hercules, the potentially responsible party, would actually be
doing the long-term monitoring for OU2.

EPA Response:  EPA will negotiate with Hercules concerning the long-term monitoring of the offsite ground
water.  If Hercules is unable or unwilling to perform the remedy,  then EPA can issue a unilateral order
forcing Hercules to do the necessary sampling. If Hercules agrees to perform the sampling for OU2, EPA will
oversee the work and take split samples from some of the monitoring locations, and send then to an
EPA-approved laboratory for analysis.  Hercules has already agreed to do the long-term monitoring for OU1,
which includes the onsite monitoring wells. A similar agreement for the OU2 sampling is likely.

        8.      Benzene in the Onsite Monitoring Wells

        PADEP commented on the presence of Benzene (a human carcinogen) in certain onsite monitoring wells,
and whether the public is adeguately protected from all of the contaminants in the onsite wells.

EPA Response:  A deed restriction which prevents using the onsite monitoring wells as a drinking water source
is a component of the OU1 remedy.  This restriction will be placed on the deed from the property after the
OU1 remedial action is completed. The nearest residential well is a long distance away from the contaminated
ground water. The waste has been in the ground for about forty years, and the contamination in the onsite
monitoring wells has been decreasing for at least the last 10 years.  If the ground water contamination was
spreading or moving in any direction, it would have reached a distant sampling location,  such as one of the
residential wells sampled in the OU1 and OU2 RI's, by now. The EPA feels that periodic monitoring itself is
an extra safety precaution.  It will detect a serious ground water problem, it one ever develops at this
Site, long before the contamination gets anywhere close to a drinking water well.

        9.      Future Residential Well in the Neighborhood

        PADEP commented on the possibility of a new well being drilled in the future near the Site.

EPA Response:  There is a remote possibility that someone would drill a drinking well in the vicinity of the
Site.   This is considered highly unlikely, due to the presence of existing water lines,  and the
undesirability of the Pittsburgh Coal ground water from the standpoint of unreliable yield and poor water
guality. No one in that neighborhood has drilled a drinking water well in at least 25 years, and with good
reason.  The public water supply is readily accessible and is more reliable and far superior in guality to a
private well.  The bedrock aguifer in the immediate vicinity of the Site yields very little water, and could
not be used as a water source.  The unconsolidated zone and the coal seam tend to completely run out of water
during dry periods.  The coal seam water has high levels of metals, dissolved solids and
sulphur compounds, mainly because of historical mining.  It would be both difficult and expensive for a
private citizen to remove all these compounds from a private well.

        10.     Declining Property Values Near Superfund Sites

        A citizen living near the Site asked if living in the general vicinity of a Superfund Site often has
a negative impact on property values.

EPA Response:  The negative connotation of a Superfund Site can have an impact on property values in its
vicinity.  People who are looking to buy a house are often frightened away if they hear that a hazardous
waste site exists in a particular neighborhood. This may be the situation even after a site cleanup has been
completed.

        11.     Monitoring in All Directions from the Site

        A citizen asked about the monitoring in the future and in which direction from the Site the
monitoring will occur offsite.

EPA Response:  Monitoring locations will be in all directions from the Site.  The EPA usually selects the

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greatest number of sampling points downgradient from the Site because that is the direction of ground water
flow.  Monitoring for OU2 will include seeps, offsite monitoring wells and as well as several
residential wells.  The monitoring program will help determine water guality in this entire area,  and the
rate of attenuation of ground water contamination in the future.

        12.     Discharging Effluent Water to WESA

        PADEP asked about the possibility of discharging wastewater from the recovery wells in Alternative 3
directly to the West Elizabeth Sanitary Authority (WESA) instead of treating the contaminated ground water
and then discharging it to the unnamed stream as described in the Proposed Plan.

EPA Response:  Direct discharge of the wastewater to the treatment plant would be difficult for a number of
reasons. First, the wastewater would have to be pre-treated because of the high levels of several metals in
the water.  The West Elizabeth Sanitary Authority is not eguipped to handle high levels of
metals, and the metals would have to be removed before the water could be discharged to the treatment plant.
Second, this pretreatment process would generate a huge guantity of metallic sludge which would be costly to
dispose of.  Sludges of this kind typically are sent to a hazardous waste treatment facility or a hazardous
waste landfill.

        Another problem with this approach is that WESA probably could not handle the increased volume.   WESA
theoretically has the capacity for this additional wastewater if their treatment plant is operating under
ideal conditions.  However, freguently the plant is operating under less than ideal conditions, and on those
occasions the plant could not handle the additional wastewater.  Wastewater recently produced during the
cleanup of the nearby Elrama Superfund site could not be handled by WESA because of this problem.   Fourth, it
is guestionable whether the sewer pipe leading from the Site to the treatment plant could handle the extra
water volume generated from a water treatment system of this kind.

        13.     Hercules Agreement with the EPA's Remedy Selection

        Hercules Inc., the only responsible party at the Site, submitted a written comment in which they
stated that they were in agreement with the EPA's selection of Alternative 2.  Hercules also described some
of the difficulties and limitations of a pump and treat system  (Alternative 3).    Hercules expressed the
opinion that no further action with offsite monitoring is the appropriate choice for the ground water
operable unit at this Site.

EPA Response:  Hercules performed the RI/FS for operable units #1 & 2.  They are in the process of completing
the Remedial Design for operable unit #1, and will soon begin the Remedial Action for the remaining
components of the source control remedy.  Hercules has been involved in the cleanup of the Resin Disposal
Site for many years.  Their agreement with EPA's selected remedy for the ground water operable unit is an
indication that Hercules may be willing to perform the future monitoring of the ground water at
the Site.

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