United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R03-92/151
Jury 1992
Superfund
Record of Decision:
Paoli Rail Yard, PA
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NOTICE
The appendices listed in the index that are not found in this document have been removed at the request of
the issuing agency. They contain material which supplement but adds no further applicable information to
the content of the document All supplemental material is, however, contained in the administrative record
for this site.
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REPORT DOCUMENTATION
PAGE
1. REPORT NO.
EPA/ROD/R03-92/151
3. Redptenfs Accession No.
4. TaeandSaMMe
SUPERFUND RECORD OF DECISION
Paoli Rail Yard, PA
First Remedial Action - Final
5. Report (M>
07/21/92
7. Autho<<«)
8. Performing Organization R*pt No.
9. PerteiiBliigOre^lnMffln Name and Address
10. ProfectfTasfc/WorktMtNo.
11. Contraet(OorGnnKG)Na.
TO
(G)
12. Spaneoring Organization Name and Address
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Rsport* Period Covered
800/000
14.
15. !
PB93-963910
16. Abstract (Unit 200 .onto)
The 428-acre Paoli Rail Yard site is a maintenance, storage, and repair facility
located north of Paoli in Chester County, Pennsylvania. The site consists of the
28-acre rail yard and the surrounding 400-acre watershed. The site, which is mainly
wooded, is bordered to the north by residential areas and to the south by commercial
developments. Since 1915, the rail yard has provided general maintenance and repair
support for rail cars. The site operates five track areas used for multiple rail
lines, a power house, a freight house, and a repair shop. Prior to 1968, the site was
owned by Pennsylvania Railroad, after which it changed hands several times. Soil
contamination in and around the car shop is attributed to releases of fuel oil and
PCB-laden transformer fluid from rail cars during maintenance and repair activities.
In 1985, EPA identified PCB contamination in soil and sediment, and on building
surfaces. The rail companies agreed to address site clean-up activities, including
erosion, sedimentation, and stormwater characteristics and control, decontamination,
soil sampling, excavation of 3,500 cubic yards residential soil, and implementation of
worker protection measures. Further EPA investigations identified soil samples in and
around the car shop, parallel to the rail tracks, and 10 feet below the facility that
(See Attached Page)
17. Document Analvsla a. DsecrlBteri
Record of Decision - Paoli Rail Yard, PA
First Remedial Action - Final
Contaminated Media: Soil, sediment, structures, gw
Key Contaminants: VOCs (benzene, ethylbenzene, toluene, xylenes), other organics (PCBs)
b. UenttfierafOpefrEmMTern*
e. COSA11 FMoYGnup
18. Availability Statement
19. Security Class (This Report)
None
2O. Security Cam (That Page)
Hone
21. No. of Pages
96
22. Price
(See AMSI-Z3S.1B)
Sao Instruction* en Rvnne
(Formerly NTIS45)
Pepsfbnsnt ot Commerce
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EPA/ROD/R03-92/151
Paoli Rail Yard, PA
First Remedial Action - Final
Abstract (Continued)
were contaminated by fuel oil in the form of benzene, toluene, ethylbenzene, and xylenes
(BTEX). Sediment samples taken from the three creeks that drained the general rail area
also showed PCB contamination decreasing further from the rail yard. Soil samples taken
from residences lying adjacent to the facility identified topsoil contamination
presumably resulting from soil erosion from the rail yard. This ROD provides a final
remedy for contaminated soil {from the rail yard and residences), sediment, and
structures at the Paoli Rail Yard, and contaminated ground water. The primary
contaminants of concern affecting the soil, sediment, debris, and ground water are VOCs,
including benzene, ethylbenzene, toluene, xylenes; and other organics, including PCBs.
The selected remedial action for this site includes excavation and onsite treatment of
approximately 28,000 cubic yards of contaminated soil with PCB concentrations of 25 mg/kg
or greater, 3,000 cubic yards of previously excavated contaminated residential soil
currently stored in an onsite containment cell, and stream sediment with
PCB concentrations exceeding 1 mg/kg using solidification/stabilization processes,
followed by disposal of the solidified waste in an onsite containment cell; onsite
decontamination of 35,000 square feet of high contact surfaces in the rail yard buildings
and structures with PCB concentrations in excess of 10 mg/100 en? ; mitigating impacts to
stream and surrounding areas from sediment excavation; pumping and onsite treatment of
fuel-oil contaminated ground water; recovering the oil using a fuel oil recovery system
and disposing of the recovered oil offsite, treating the ground water using filtration
and activated carbon with onsite discharge through a subsurface infiltration gallery;
implementing erosion controls to manage sediment and stormwater runoff; conducting
long-term ground water monitoring; and implementing institutional controls, including
deed restrictions. The estimated present worth cost for this remedial action is
$28,268,000, which includes an O&M cost of $494,000 for years 0-2 and $258,250 for the
remaining 7.5 years.
PERFORMANCE STANDARDS OR GOALS: Soil clean-up standards at the rail yard are based on
health-based levels, including PCB 4 ug/kg for soil onsite and for residential areas
include a. clean-up level of 2 mg/kg or less. Chemical-specific ground water clean-up
goals are based on the more stringent of state standards or SDWA MCLs, and include
benzene 5 ug/1, and background levels for ethylbenzene, toluene, and xylenes. An ARAR
waiver also will be issued for certain management controls at the TSCA waste landfill
under CERCLA 121(d)(4).
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Paoli Rail Yard Superfund Site
Paoli, Chester County, Pennsylvania
DECLARATION
Site Name and Location
Paoli Rail Yard
Paoli, Pennsylvania
Statement of Basis and Purpose
This decision document presents the final selected remedial
action for the Paoli Rail Yard Site in Paoli, Pennsylvania,
developed in accordance with the Comprehensive Environmental
Response, Compensation, and Liability Act of 1980, as amended by
the Superfund Amendments and Reauthorization Act of 1986
("CERCLA"), 42 U.S.C. SS9601 e£ seg., and to the extent
practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP), 40 C.F.R. Part 300. This decision
document explains the factual and legal basis for selecting the
remedies for this Site.
The Commonwealth of Pennsylvania concurs with the selected
remedies. The information supporting this remedial action
selection decision is contained in the Administrative Record for
the Site.
Assessment of the Site
Pursuant to duly delegated authority, I hereby determine,
pursuant to Section 106 of CERCLA, 42 U.S.C. S 9606, that actual
or threatened releases of hazardous substances from this Site, as
discussed in the Summary of Site Risks, if not addressed by
implementing the response actions selected in this Record of
Decision, may present an imminent and substantial endangerment to
public health, welfare, or the environment.
Description of the Selected Remedies
These are the only planned response actions for the Site. These
remedies address both ground water remediation and source cqntrol
of soils, sediments, and buildings and structures contaminated
with PCBs, and considered to be a principal threat.
The selected remedies includes the following major components:
• Excavation and on-site treatment of 28,000 cubic
yards of contaminated rail yard soils using a
solidification/stabilization process for soils with PCS
concentrations exceeding 25 parts per million ("ppm").
The treated soil would be placed back on the rail yard
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in a containment cell. Long-term ground water
monitoring would be required in the immediate vicinity
of the containment cell;
• Erosion and sedimentation controls to manage and control
storm water runoff and sediment from the rail yard;
• Deed restrictions on the rail yard will be developed to
protect the integrity 'of the remedy and will prohibit use of
the property for residential or agricultural purposes and to
prohibit the use of on-site ground water for domestic
purposes;
• Decontamination of buildings and structures on the rail
yard property to minimize exposure to persons working on the
Site. This would involve decontaminating approximately
35,000 square feet of high contact surfaces in the car shop
buildings having PCB concentrations in excess of 10 ug/100
cm2. Depending on the type of surface, decontamination
would be accomplished by wiping with a solvent, applying a
chemical foam, shot blasting, or similar methods;
• Excavation and treatment of PCB-contaminated residential
soils. The cleanup standard is to achieve an average PCB
concentration of 2 ppm for each individual property.
Excavated soil would be returned to rail yard property and
treated using the solidification/stabilization process;
• Pumping of ground water contaminated with fuel oil at the
rail yard using extraction wells, fuel oil recovery, ground
water treatment using filtration and activated carbon, and
discharge of the treated ground water on-site through a
subsurface infiltration gallery. The recovered fuel oil is
disposed off-site at an approved RCRA facility. This
remedial alternative is currently being implemented;
• Long-term ground water monitoring to evaluate the
effectiveness of the ground water pumping and treatment
system and fuel oil recovery system;
• Excavation and treatment of stream sediments along North
valley Creek, Hollow Creek, and Cedar Hollow Creek (all
tributaries to Little Valley Creek) and Little Valley creek
and Valley Creek with PCB concentrations exceeding l ppm.
Contaminated sediments would be returned to the rail yard
and treated using solidification/stabilization. Adverse
impacts to the stream(s) and surrounding area shall be
mitigated to the maximum extent practicable.
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Ground water monitoring wells installed during the remedial
investigation (Rl) indicate ground water occurs at depths of 35
to 50 feet below the surface. Soil extends approximately 20 feet
below the surface and bedrock the remaining depth below the soil.
During the RI it was determined that fuel oil from leaking
underground fuel oil transfer lines migrated vertically downward
through the soil and through approximately 10 feet of
unsaturated bedrock before collecting on the water table within
the bedrock aquifer. During the RI it was determined that this
10 foot zone of unsaturated bedrock has been contaminated with
fuel oil. A ground water divide is believed to exist immediately
south of the rail yard in the east west direction. Ground water
flow from the rail yard is toward the residential neighborhood
north of the rail yard.
The majority of homes within the immediate vicinity north of the
rail yard use private water supply and are serviced by
Philadelphia Suburban Water Company. The Malvern Public Water
Supply well field is located approximately 1.5 miles southwest of
the rail yard. Three private water supply wells are located
approximately 1/4 mile from the rail yard along Hollow Road.
The rail yard itself is enclosed by a fence and access is
limited. The rail yard includes three main structures and five
distinct track areas. . The buildings include the car shop, power
house and freight house. The study of PCS contamination has
concentrated on the car shop, where rail cars are repaired. The
track areas include a staging area for commuter trains,'the car
shop entrance and exit, the Harrisburg rail line, and the
turnaround track.
The rail yard dates to 1915, when the car shop was built. The
shop was designed to repair passenger rail cars, which were
steam-powered at the time. The rail lines were later converted
to electrical power at which time mineral oil was used to cool
the transformers in the trains. In the 1950's, PCBs replaced the
mineral oil in the transformers. Although operational records
are limited, it appears that maintenance and repair practices at
the rail yard resulted in the PCB soil contamination. PCBs in
railroad transformer* arc released during servicing and
volatilize during overheating in operation. For example,
Westinghouse Electric Corporation has indicated that as much as
30 percent of the dielectric fluid of a railroad transformer can
leak before the unit fails (see Federal Register, January 3,.
1983, page 128). Much of the PCB-contaminated soil is located in
the rail yard trade area where rail cars were operated.
Ownership of the rail yard has changed several times since 1915.
The yard is now owned by the National Railroad Passenger
Corporation ("Amtrak") and is operated by the Southeastern
Pennsylvania Transportation Authority ("SEPTA"). The yard was
originally owned and operated by the Pennsylvania Railroad, when
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Decision Summary for
Paoli Rail Yard
Paoli, Pennsylvania
I. SITE NAME. BACKGROUND AND DESCRIPTION
Paoli Rail Yard
Paoli, Chester County, Pennsylvania
The Paoli Rail Yard Site ("the Site") is located north of the
town of Paoli, in Chester County, Pennsylvania. The Site
includes the 28 acre rail yard and the surrounding 400-acre
watershed. The rail yard is bordered by Central Avenue to the
north (and several private residential properties), North Valley
Road to the east, the AMTRAK Harrisburg line to the south and the
turnaround track to the west. A residential area lies to the
north of the Site and a commercial development to the south.
Lancaster Avenue (US Rt. 30) is south of the rail yard and is the
main street of Paoli. The watershed includes three tributaries
(Cedar Hollow, Hollow and North Valley) to Little Valley CreeX
and Valley Creek (Refer to Figure 1 and 2).
The Site is located in both Willistown and Tredyffrin Townships.
The town of Paoli has a population of 6,100. The population of
willistown Township is 8,710 and of Tredyffrin Township is
26,690. The Site is zoned commercial.
The Paoli Rail Yard Study Area ("the study area") is primarily
comprised of wooded and open parcels of land and residential
properties to the north of the rail yard, and light commercial
zones to the south of the rail yard (Refer to Figure 3). Three
tributaries, which roughly parallel Cedar Hollow, Hollow, and
North Valley Roads, emerge between 500 and 1000 feet north of the
rail yard, flow north, and discharge into Little Valley Creek.
Stream investigations were conducted in the three tributaries and
in Little Valley and Valley Creeks. Prior to the installation of
erosion control systems along the northern portion of the rail
yard in 1986-1987, Hollow Road and Hollow Tributary formed a
predominant erosion and drainage pathway from the rail yard. PCB
contaminated soil eroded off the rail yard property through this
and other drainage pathways into the nearby residential community
and streams.
Most of the rail yard is covered with fill materials consisting
of cinder, ash, and minor building debris in a clayey silt matrix
at depths of about two feet. The underlying native soil is a
loamy silty soil and silty soil, with increasing depth, the
amount of schist fragments increases consistent with the
saprolitic origin of these soils.
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RECORD OF DECISION
SECTION PAGE
I. SITE NAME, BACKGROUND AND DESCRIPTION 2
II. SITE HISTORY AND ENFORCEMENT ACTIVITIES 4
•
III. COMMUNITY RELATIONS 6
IV. SCOPE AND ROLE OF REMEDIAL ACTION 6
V. SUMMARY OF SITE CHARACTERISTICS AND 7
EXTENT OF CONTAMINATION
VI. SUMMARY OF SITE RISKS 19
VII. REMEDIAL ACTION OBJECTIVES 25
VIII. DESCRIPTION OF ALTERNATIVES 27
IX. SUMMARY OF COMPARATIVE ANALYSIS 45
OF ALTERNATIVES
X. SELECTED REMEDY: DESCRIPTION AND 56
PERFORMANCE STANDARD (s) FOR EACH
COMPONENT OF THE REMEDY
XI. STATUTORY DETERMINATIONS 64
XII. DOCUMENTATION OF SIGNIFICANT CHANGES 74
FIGURES
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Statutory Determinations
The selected remedies are protective of human health and the
environment; comply with Federal and State requirements that are
applicable or relevant and appropriate to the remedial action; or
a waiv.er can be justified for any Federal and State applicable or
relevant and appropriate requirement that will not be met; and is
cost-effective. These remedies utilize permanent solutions and
alternative treatment (or resource recovery) technologies to the
maximum extent practicable, and satisfy the statutory preference
for remedies that employ treatment that reduces toxicity,
mobility, or volume as a principal element.
Because these remedies will result in hazardous substances
remaining on-site above health-based levels, a review will be
conducted within five years after commencement of remedial action
and every five years thereafter, as required by Section 121(c) of
CERCLA, 42 U.S.C. §9621(c), to ensure that the remedies provide
adequate protection of human health and the environment.
JUL 211992
Edwin B. Erickson Date
Regional Administrator
Region III
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the Pennsylvania Railroad and the New YorJc Central Railroad
merged in 1968, the yard was operated by the new Perm Central
Transportation Company ("PCTC"). Amtrak took ownership of the
rail yard during the bankruptcy reorganization of PCTC in 1976.
Conrail operated the yard, during Amtrak ownership, from 1976
until 1982 when SEPTA took over operations.
The Paoli rail yard is used for storage and maintenance of
passenger rail cars. The tracks leading to the car shop run along
the northern portion of the property and extend through the car
shop. The rail yard is accessed by workers from Central Avenue.
The car shop tracks are separated from the Harrisburg Rail Line
to the south by an elevated strip of land. The Harrisburg Rail
Line is used for passenger and freight transportation. The
southernmost section of track is referred to as the turnaround
track, which is used to transfer rail cars between the car shop
and the Harrisburg Rail Line.
In December 1991, EPA was notified that SEPTA had decided to
discontinue all rail car maintenance and storage activities at
the Paoli rail yard by June 30, 1994. After that time the rail
yard will be closed. The rail yard and area immediately
surrounding are zoned commercial. Land use North of the rail
yard is residential.
II. 8ITB HISTORY AND EOTORCEMBirr ACTIVITIES
EPA initially became aware of the PCB contamination at the Site
as a result of investigations conducted pursuant to the Agency's
authority under the Toxic Substances Control Act (TSCA), 15
U.S.C. §S 2601 to 2671. Information received from the rail
companies in response to TSCA subpoenas issued in 1985 revealed
that extremely elevated levels of PCBs were present onsite. As a
result, the United States and the rail companies, SEPTA, Amtrak,
and Conrail, have entered into five (5) separate Consent Decrees
("CDs") which addressed various clean-up activities and worker
protection measures at the Site and in th« surrounding community.
Under the first CD entered in February 1986, the rail companies
installed a security fence and a geotextile fabric fence around
the perimeter of the Site. At this time, EPA conducted some
offsite soil sampling, and restricted access to the Site.
Sampling results revealed elevated levels of PCB contamination
offsite.
The rail companies then undertook an engineering study under the
second CD which addressed erosion, sedimentation, and storm water
characteristics and control, at and from the facility and its
immediate surroundings. In September 1986, subsequent to a
hearing before Judge Scirica, in the United States District Court
for the Eastern District of Pennsylvania at which EPA sought
emergency access to the Site, EPA commenced construction of
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sedimentation and erosion control facilities including storm
water collection basins A (western basin), B (central basin), and
C (eastern basin), and associated drainage facilities. EPA
remained onsite for a period of approximately two years, until
June 1988.
Under the third CO the rail companies performed a Remedial
Investigation/Feasibility Study ("RI/FS") for the Site. As part
of this CD, the United States and the defendants entered into a
worker-protection stipulation which addressed contamination
inside the Paoli car shop. The stipulation called for, among
other things, decontamination of specific areas in the car shop
and implementation of a routine maintenance program for
particular areas including the lunchroom, locker room
("clean-side/worker-side" lockers; laundry service), offices and
other work storage areas.
The fourth CD, entered in November 1987, called for soil sampling
in the residential areas immediately north of the Paoli rail yard
(the "residential area") and the surface water channels extending
north of the rail yard, up to, and including Little Valley Creek.
Sampling results revealed elevated levels of PCBs in some of the
residences adjacent to the Site.
As a result of PCBs discovered in nearby residences, the rail
companies entered into a fifth CD in September 1988. Under this
CD, the rail companies excavated 3500 cubic yards of contaminated
soil from 35 residences directly north of the rail yard. The
excavated properties were restored to original condition prior to
the excavation.
On September 26, 1983, SEPTA, independent of any CDs, initiated
the first phase of a rail car transformer retro-fill program that
continued through August 1984. The second phase of the retro-fill
program began in November 1985 and continued through July 1986.
This retro-fill program was implemented in response to TSCA
regulations at 40 C.F.R. S 761 which require retro-fill programs
to replace PCS fluids with other coolants. Prior to the July l,
1979, records on the handling of PCB transformer fluids were not
required to be maintained by TSCA regulations. Thus, there are
few records regarding earlier time periods.
As to previous EPA actions at the Site, EPA has performed the
following off-sit* response actions. In March 1986, EPA placed a
tarpaulin over approximately 10,000 square feet of soil in the
backyard of 100 Central Avenue using a geo-textile fabric. In
October 1986, EPA initiated a removal action which included the
excavation of 671 cubic yards of off-site soils in the vicinity
100, 96, 90, and 84 Central Avenue and 15 Minor Avenue.
This document is the first and final Record of Decision (ROD) for
the Site; it will address all components of the remedies.
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III. eOMMPKITY RELATIONS
Throughout the Site's history, community concern and involvement
have been high. EPA has kept the community and other interested
parties apprised of the Site activities through informational
meetings, fact sheets, press releases and public meetings.
A Community Relations Plan for the Paoli Rail Yard Site was
finalized in April 1991. This document lists contacts and
interested parties throughout government and the local community.
It also established communication pathways to ensure timely
dissemination of pertinent information. The PRPs' draft Remedial
Investigation/Risk Assessment (RI/RA) and Feasibility Study (FS)
reports, EPA's baseline risk assessment, and the Proposed Plan
were released to the public in March 1992. All of these
documents were made available in both the Administrative Record
located in the EPA Public Reading Room in Region III and at the
Paoli Public Library. A public comment period was held from
March 15, 1992 to April 15, 1992, and extended to May 15, 1992.
In addition, a public meeting was held'on March 24, 1992, to
discuss the results of the RI/RA and FS and the preferred
alternative as presented in the Proposed Plan for the Site.
Notice of the Proposed Plan and public meeting was published in
the Philadelphia Inquirer. All comments received by EPA prior to
the end of the public comment period, including those expressed
verbally at the public meeting, are addressed in the
Responsiveness Summary attached to this Record of Decision.
IV. SCOPE AMD ROfrB QT THB P*1TBPInI( ACTIOW
Three Potentially Responsible Parties (PRPs) - SEPTA, Amtrak, and
Conrail - conducted an RZ/RA and FS at the Site under the
supervision of EPA pursuant to an administrative order by consent
signed by the PRPs and EPA in 1987. The RI/RA and FS consisted
of investigations and studies to characterize the type and extent
of contamination in the entire study area and to develop
alternatives to address the contamination problems.
The remedies selected in this ROD are the only planned response
actions for this Sit*. The remedial action objectives are as
follows:
• Source control of rail yard soil contaminated with PCB
concentrations above 25 parts per million (ppm) to prevent
exposure through direct contact.
• Decontamination of buildings and structures on the rail
yard property to minimize exposure of persons working on the
Site.
• Excavation of residential soils contaminated with PCBs to
prevent exposure through direct contact.
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• Recovery of fuel oil and entrained PCBs from the ground
water in the vicinity of the rail yard car shop building and
treatment of ground water.
• Excavation of sediments in streams and tributaries to
grovide adequate protection of human health and the
environment.
Zt SUMMARY OF 8ITB CHARACTERISTICS AND EOTEMT OT COKTAMIKVPTQK
The environmental media characterized during the RI included
soil, ground water, air, surface water, stream sediment, building
surfaces, and aquatic organisms. The investigation focused
primarily on the drainage and erosion areas where PCBs were
deposited. Detailed discussions concerning the extent of
contamination are presented in Chapter 3 of the RI/RA report.
The principal contaminant of concern at the Site is PCBs. PCBs
were detected in rail yard soils, residential soils, stream
sediments, and fish. PCBs were not detected in ground water
outside of the vicinity of the car shop and were determined to be
present below the level of quantification in wells containing
fuel oil, probably due to cross contamination with the fuel oil
which is known to mobilize PCBs. Fuel oil which previously
leaked into the ground near the repair shop on the north side of
the rail yard does contain PCBs and elevated levels of benzene,
toluene, ethylbenzene, and xylene (BTEX). Benzene has been
detected at concentrations in ground water that exceed Maximum
Contaminant Levels ("MCLs") under the Safe Drinking Water Act
("SDWA"), 42 U.S.C. SS 300f-300j and the regulations at 40 c.F.R.
§ 141.61. BTEX compounds are contaminants of concern at this
Site.
Erosion of PCB-contaminated ^oil from the rail yard to
residential soil and to tributaries of Little Valley Creek and
Valley Creek prior to 1986 when sediment erosion control measures
were put in place is the most significant pathway for movement of
PCBs (Refer to Figure 4). In general, a marked pattern of
decreasing PCB contamination in stream tributary sediments is
evident with increasing distance from the rail yard.
The concentration of PCBs detected in residential soil and stream
sediments is approximately three orders of magnitude lower than
the PCB concentration in the rail yard. PCBs were not detected
in surface water and ground water but PCBs were determined to be
present in the fuel oil. The fuel oil has contaminated the
subsurface soil and has migrated into the fractures of the
bedrock above the water table in the vicinity of the car shop
building.
Table 1 shows the range of PCB concentration for selected media.
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Surface Water Hydrology
K.S previously mentioned, there are three tributaries (located
parallel to Cedar Hollow, Hollow, and North Valley Roads) which
discharge to Little Valley Creek. The headwaters to the Cedar
Hollow Road (CHR) Tributary emanate approximately 1400 feet
northwest of Central Avenue along Cedar Hollow Road. The
headwaters to the Hollow Road (HR) Tributary emanate
approximately 450 feet north of Central Avenue along Hollow Road,
and the headwaters to the North Valley Road (NVR) Tributary
emanate approximately 900 feet north of Central Avenue along
North Valley Road.
During RI sampling, eighteen surface water samples collected from
the three tributaries to Little Valley Creek and 15 samples
collected from Little Valley and Valley Creeks were analyzed for
PCBs. Two rounds of samples were collected; one before and one
after a rain event. PCBs were detected at a maximum
concentration of 1.8 parts per billion (ppb) at the headwaters of
CHR tributary. PCBs were not detected* in any other surface water
samples (Refer to Figures 5 and 6).
A topographic high located south of the rail yard marks the
southern edge of a surface water divide for the drainage basin
associated with the rail yard. Precipitation that falls on any.
portion of the rail yard would have its surface water movement
limited to areas immediately to the north of the rail yard
including the three tributaries that receive surface drainage
from the rail yard. Prior to the yard installation of erosion
control systems along the northern perimeter of the rail yard, a
study was performed by Groundwater Technology Inc. ("GTX"), on
behalf of the Rail Companies, that showed surface water flowed
primarily via sheet flow to the north. The document runoff
outlet and sediment loss pathway was along Hollow Road which
drained the central portion of the rail yard and North Valley
Road which drained the eastern portion of the rail yard.
Surface drainage patterns were altered in 1986 by the
installation of erosion control features along the northern
perimeter of the rail yard. These features include the
installation of an anchored sedimentation control fence
(utilizing high strength, woven, UV resistent fabric) and
sedimentation basins. Rail yard surface water continues to be
controlled by these techniques.
Cedar Hollow Read Tributary
The approximate elevation at the headwaters of the CHR Tributary
is 405 feet above mean sea level. The tributary flows northwest
approximately 625 feet along the west side of Cedar Hollow Road
before it is channeled underground through a drainage pipe
adjacent to an industrial park. The CHR Tributary bottom
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14
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consists primarily of weathered schist fragments with lesser
amounts of silty sand in depositional areas. The CHR Tributary
ranges from 5 to 6 feet wide and 2 to 4 inches deep (depth of
water).
The drainage pipe extends approximately 500 feet to the northwest
before the tributary resurfaces along the east side of Cedar
Hollow Road. The elevation of the tributary where it resurfaces
at the end of the drainage pipe is 310 feet. From this point,
the CHR Tributary flows approximately 1625 feet to the north
through woods and fields until it joins Hollow Road (HR)
Tributary. The bottom sediments in this section consist
primarily of clayey silts to gravelly sands and this section is 3
to 5 feet wide and 2 to 4 inches deep.
From this point where HR Tributary merges with CHR Tributary, the
tributary flows north approximately 1100 feet before it flows
into Little Creek. The average slope of this segment is 0.02.
The bottom sediments in this section of CHR Tributary consist
primarily of clayey silts to gravelly sands and the tributary is
3 to 5 feet wide and 2 to 4 inches deep.
Based on estimations of surface flow velocity measurements
obtained during the RI from three sampling stations set at
upstream, mid-stream and downstream locations in Cedar Hollow
Road Tributary, the surface flow velocity is estimated to range
from 1.3 to 1.8 feet/second.
Hollow Road Tributary
The approximate elevation at the headwaters of HR Tributary which
begins at the end of Hollow Road is 460 feet. The HR Tributary
is steepest for the first 1000 feet as it flows to the northwest.
The bottom sediments consist primarily of weathered schist
fragments with some sandy silt that accumulates in small pool
deposits. This section of the tributary is 3 feet wide and 2 to
3 inches deep.
HR Tributary continues approximately 2400 feet to the northwest
before its confluence with CHR Tributary. The average slope of
this section of the HR Tributary is 0.07. The bottom sediments
consist primarily of clayey silts to silty sands and the
tributary is 3 to 5 feet wide and 3 to 6 inches deep. Based on
an estimate from a single surface velocity measurement at a '
sampling station in HR Tributary, the flow velocity is 0.6
feet/second.
North Valley Road Tributary
The approximate elevation at the headwaters of NVR Tributary,
which flows along the vest side of North Valley Road, is 450
feet. The NVR Tributary is the steepest for the first 940 feet
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as it flows to the north-northwest. The average slope of the NVR
Tributary is 0.10 in this section. The bottom sediments consist
of weathered schist fragments with lesser amounts of sandy silt
that accumulates in small depositional areas. The tributary is 3
feet wide and 3 to 6 inches deep.
NVR Tributary continues approximately 2,250 feet to the north
before it is channeled underground through a concrete drainage
pipe. The drainage pipe extends approximately 500 feet to the
north. The distance from the point where the tributary
resurfaces at the northern end of the drainage pipe to the point
where NVR Tributary converges with Little Valley creek is
approximately 1000 feet. The average slope of the NVR Tributary
along the total distance of 3,750 feet is 0.05. The bottom
sediments consist of clayey silts to gravelly sands, and the
tributary is 3 to 4.5 feet wide and 0 to 11 inches deep. The NVR
Tributary was dry in many locations, and where water flowed,
stream obstructions prevented measurement of surface flow
velocity.
Little Valley Creek and Vallev Creek
Little Valley Creek flows from west to east, nearly perpendicular
to the three tributaries. HR and CHR Tributaries meet
approximately 1100 feet upstream of their confluence with Little
Valley Creek. The elevation of Little Valley Creek at its
confluence with CHR Tributary is 200 feet. The Little Valley
Creek measures about 2500 feet between its confluence with CHR
Tributary and its confluence with NVR Tributary. The slope of
Little Valley Creek along this section is 0.008. The elevation
of Little Valley Creek at its confluence with NVR Tributary is
180 feet. Little Valley Creek spans a distance of about 7000
feet from its confluence with NVR Tributary northeast to its
confluence with Valley Creek. The slope of Little Valley Creek
in this section im 0.007. The elevation at its confluence of
Little Valley Creek with Valley Creek is about 130 feet. Valley
creek ultimately discharges into the Schuylkill River,
approximately 6.5 miles northeast of the rail yard.
The three tributaries that parallel Cedar Hollow, Hollow, and
North Valley Roads are narrow, shallow, and steep, when compared
with Little Valley Creek and Valley Creek. Recreational use of
the three tributaries is minimal. The tributaries are not
physically suited for swimming or fishing, however, fishing in
Little Valley Creek and Valley Creek does occur. Although these
creeks are not sufficiently deep for swimming, people may wad* in
the creeks.
According to Pennsylvania Water Quality Standards, Valley Creek
is designated a trout-stocking stream under Chapter 93 of the
Pennsylvania Code, Title 25. There are no Pennsylvania stream
designations for the tributaries. There is currently a ban on
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fish consumption in Valley Creek and fishing is on a
catch-and-release basis.
Sit* Hydrogeology
A total of 25 monitoring wells were installed and monitored
during the remedial investigation. This study showed that a
ground water divide, located south of the rail yard, follows a
northeast-southwest topographic ridge that separates ground water
movement from the rail yard from the ground water basin to the
south of the rail yard. To the south of the rail yard, a
physical discontinuity (a ridge line) exists between ground water
occurrence from the Paoli rail yard from other ground water
basins in a southerly direction. This ridge line, located
immediately south of the rail yard, parallels Route 30 in an
east/west direction.
Geology
*
The rail yard and study area are located within the Piedmont
Upland Section of the Piedmont Province. The Piedmont Uplands
formed from uplifting which resulted in high-angle faulting and
formation of folded anticlines. An understanding of this geology
is critically important to study area modelling and ground water
flow predictions.
The rail yard is underlain by the Precambrian to lower Paleozoic
aged Wissahickon Formation. The Wissahickon Formation is a
medium to coarse-grained, phyllitic schist consisting primarily
of quartz, feldspar, muscovite, and chlorite. The estimated
thickness of the Wissahickon Formation in the vicinity of the
study area is 8,000 to 10,000 feet. The general geologic
structure (trend and lineation) of the bedrock tends to follow
east-northeast to vest-southwest patterns with nearly vertical
planes of schistosity. The subsurface's geologic structure
evidences itself as ridge lines that form ground water and
surface divides.
The topography overlying the local geology is characterized as
undulating hills of medium relief; natural slopes are moderately
steep and stable. The nature of the metamorphic bedrock is such
that differential weathering of the bedrock has produced a
generally deep subsurface profile ranging from silt loams soil to
saprolite (low permeability weathered rock) at depth.
Regionally, the saprolite thickness ranges from 15 to 25 feet and
is distributed in a blanket-like manner. This deep soil and
saprolite sequence has a substantial attenuating effect on the
infiltration of chemicals and their subsequent movement in the
subsurface.
The Wissahickon Formation crops out in several locations within
the study area, particularly in the vicinity of the turnaround
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track and north of the Site along cedar Hollow Road. The
medium-grained, muscovite-rich, phyllitic schist exposed at the
rail yard and along Cedar Hollow Road exhibits vertically to
subvertically-dipping schistocity layers. The schistocity layers
(trend) strike N65*E and are vertical to near vertical with a dip
of schistosity at SO* to 90* to the south. The planes of
schistocity (layers) are .closely-spaced and fractured. These
schistose layers are highly weathered along these zones as
indicated by the friable nature of the weathered bedrock and iron
oxidation coatings along the schistosity. The weathering and
healing process was observed to greatly impede fluids movement.
Some quartz replacement was observed along the schistose layers.
A poorly developed subtle joint set was also measured at the
outcrops. The joint set strikes N5*£ and dips approximately 40*
to the east. Joints are randomly spaced three to five feet
apart. Each joint is narrow, tight and does not exhibit the
degree of iron oxidation or quartz replacement seen along the
schistosity layers. No movement of fluids was observed along
these subtle poorly developed joints. •
The bedrock at the extreme north of the study area (approximately
\ mile) is described as the Conestoga Formation. The Lower
Ordovician-aged Conestoga Formation consists of thin-bedded
medium gray, impure limestone with black, graphite shale
partings, and conglomeratic at base. The total thickness of the
Conestoga Formation is unknown, but is at least 300 feet thick.
The topography of this area is characterized by rolling valleys
and hills of low relief and natural slopes that are gentle and
stable. This geologic sequence also tends to produce a silty
clay, low permeable, soil cover that overlies bedrock.
Rail Yard Soils
The Paoli Rail Yard is best characterized as fill located on top
of a soil sequence known as the Glenelg channery silt loam which,
when undisturbed, has a 3% to 8% slop* and is moderately eroded.
The Glenelg Series is capable of moderate soil moisture and is
moderately fertile. The typical Glenelg Series soil profile
consists of a horizon of dark-brown to very gray-brown channery
silt to gritty silt loam with sub-angular blocky structure,
partial clay film* on beds, and firm consistency. The
undisturbed soil sequence generally has a zone at a depth of
alluviated (accumulated) silts and clays which greatly restrict
downward movement of water, metals and organic*.
The northern portion of the study area is located within the
Hagerstown-Conestoga-Guthrie soil association which consists of
several silt loam series including the Conestoga, Hagerstown,
Bedford, Hoilinger, Guthrie, and Lawrence silt loams.
Host of the area of the rail yard (28 acres) is covered with fill
materials consisting of cinder, ash and minor building debris in
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a clayey silt matrix. The cinder/silt matrix was accumulated
during previous coal-powered operations on the rail yard. This
layer of ash and cinder is predominantly restricted to the upper
few feet of the rail yard. This fill sequence has been found to
be quite unique, consisting of a general silt clay matrix of low
permeability (10~5 to 10~6 cm/sec), and with a relative high
carbon content (greater than 5%) and laced with the
honeycomb-like cinder ash. . The combined effect of the
silt/clay-organic carbon and ash/cinder matrix from field
investigations evidences it to be a sponge-like trap for oils and
other fluids. Below the fill material in most areas, the natural
soil profile extends vertically downward to native decomposed
bedrock fragments.
Both surface soil samples and soil borings were collected on the
rail yard during the RI using a systematic sampling program to
determine the lateral and vertical extent of PCBs. Approximately
200 surface soil samples were also collected during the RI. The
maximum detected PCB concentration was 6000 ppm. A PCB
isoconcentration map (Figure 1-9 in the FS) shows the
concentration of PCBs using surface soil sampling data. The map
shows that the highest PCB concentration closely follows the rail
track area and decreases rapidly outside of the immediate track
area.
Based on the soil borings completed at the rail yard, the lateral
and vertical extent of the fill material has been determined. In
most of the track areas on the rail yard, the top one to three
feet of fill consists of ballast, cinder and silts. It should be
noted that much of this ballast at the Paoli Rail Yard is not a
true stone ballast but consists of large cinder pieces
accumulated during coal-powered operations at the rail yard. In
two areas: (1) east and west of the car shop, and (2) the
vicinity of storm water basin c, the fill thickness ranges from
approximately three to six feet and consists primarily of cinder
and silt. In an area north of the car shop, the fill thickness
ranges from six to seventeen feet and consists primarily of
cinder, silt, and minor building debris. In this location, the
original soil profile has been disturbed. The natural soils on
the rail yard have a permeability in the 10"5 to 10~6 cm/sec
range.
Residential Soils
During the RI soils were sampled in the nearby residential area
north of the rail yard using a combined systematic and judgmental
sampling program. Soil samples were collected from residential
yards, residential gardens and play areas, and along road
drainage features*
Over 400 samples were collected using a tiered sampling protocol
identified in the RI as Level I, II, III, and IV. Level I
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included residential and commercial properties located
topographically downgradient of the rail yard where contaminated
sediment was most likely to be deposited through erosion and
runoff. Composite samples were collected from front yards, back
yards,_and gardens. Level II included residential properties
located topographically upgradient of the rail yard that would
not directly receive runoff from the rail yard. Front yard
composite samples were collected from every fourth residential
property, as well as surface soil samples from gardens. Level
III consisted of collection of biased grab samples from drainage
features along roads, drainage channels on residential properties
(including Level I and II areas) and along tributaries. The
purpose of this sampling was to determine direct surface runoff
pathways. Level IV sampling consisted of random composite
samples that were taken through the entire 400-acre study area.
The maximum PCB concentration for the front and back yard
composite samples was 21 ppm PCB. The maximum PCB composite
concentration reported for flower garden and vegetable garden
soil samples was 25 ppm. Approximately 35 properties have
composite samples that exceed 5 ppm PCBs, either in front or back
yards or in soil from gardens. The maximum drainage sample
detected was 28 ppm PCB. The previous residential soil removal
programs were intended to excavate surface soils with a PCB
concentration exceeding 50 ppm. None of the additional sampling
conducted during the RI detected surface soil samples with PCB
concentration exceeding 50 ppm.
Regional Hydrogeology
The ground water basin associated with the study area is in the
Wissahickon Formation. Available regional information was
complied to compare regional and site-specific aquifer
characteristics. On a regional basis, the Wissahickon Formation
is capable of storing and transmitting ground water from
precipitation that has infiltrated downward through soil and into
bedrock through secondary low porosity features such as
fractures, faults, joints, and relict bedding planes. A
lineament study in the region revealed the presence of two
lineament trends. On* trend strikes NO4- 10°W and the second
trend strikes N50»- 60«W. Neither of these trends evidence
themselves on the study area in outcrop exposures or in cuttings
from the wells constructed.
Depending on topography, the water table in the Wissahickon
Formation nay occur in saprolitic soil (generally in valleys and
low-lying areas) or in fractured bedrock (generally on hilltops
and medium-relief hillsides). The wells in the Wissahickon
Formation that are located on hills have significantly lower
yields than wells located in valleys. The hydraulic conductivity
decreases with depth due to a decrease in fracturing and
weathering with depth and due to healing of fractures as a result
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of overburden pressure and mineralization.
The Wissahickon Formation is generally a low permeability
formation, yet occasionally it can exhibit a wide-range of
aquifer characteristic values and be considered extremely
heterogeneous and anisotropic. The storage coefficient in valley
saprolitic soil averages 0.08. The storage coefficient in the
upper 2,000 feet of the.bedrock is typically 0.002. The storage
coefficient in the upper 460 feet of the Wissahickon Formation
has been estimated to range between 0.00007 and 0.0005 with a
median value of 0.0003. The transmissivity (ability to transmit
fluids) in the upper 460 feet of the Wissahickon Formation has
been estimated to range between 540 and 14,000 gallons per day/
per foot (gpd/ft) with a median value of 860 gpd/ft.
A physical discontinuity exists between the ground water that
occurs south of the rail yard and that which exists beneath and
north of the rail yard. This discontinuity exists in the form of
a topographic ridge line that is developed over the underlying
geologic structure which forms the ground water divide. The RI
identified the presence of a ground water divide that is located
to the south of the rail yard and follows a northeast-southwest
trending topographic ridge. As noted previously, the trend of
this divide follows the geologic structure of the foliation of
the schist bedrock (dominant East/West trends with near vertical
planes of schistosity). The presence of this topographic ridge
and the foliation of the schist bedrock creates a divide which
separates ground water movement from the rail yard (drains to the
north) from the ground water basin to the south of the rail yard.
The ridge line, located immediately south of the rail yard,
parallels Route 30 in a general east/west direction. Its
behavior as a ground water barrier/divide for north/south
movement of ground water is confirmed by ground water liquid
level measurements obtained from monitoring wells.
Ambient Air
During the remedial investigation, an ambient air investigation
was performed at locations outside the car shop near areas with
high PCB concentrations in soil and inside the car shop. The
primary sources of PCBs for air migration are areas of exposed
soil where elevated PCB concentrations have been reported. Four
rounds of ambient air sampling were collected from three sampling
stations and one background station and analyzed for PCBs. • The
background samples ranged from 0.004 to 0.097 ug/m3. Samples
from the other three sampling stations ranged from 0.025 to 1.134
ug/m3. Air samples taken inside the car shop ranged from 0.38 to
0.72 ug/m3. The OSHA standard is 500 ug/m3 (Refer to Figure 7).
car Shop
A comprehensive investigation was performed during the RI to
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assess the distribution of PCBs within the car shop. The car
shop is located in the northwestern section of the rail yard.
The car shop is an active facility used primarily to repair and
maintain rail cars. To determine the extent and concentrations
of PCBs, surfaces within the car shop, including ceilings, walls,
and permanent structures, were sampled. Cement and other core
samples' were also taken to determine the vertical extent of PCBs
in the car shop. A total of 149 surface wipe samples were
collected. PCBs were detected at concentrations ranging from
undetected to 823 ug/100 cm2. In addition, 39 concrete core
samples were taken ranging from 0-7 inch depth intervals in
various locations throughout the car shop. Additionally, cores
were completed through other porous surfaces. The highest PCB
levels were detected in cement near the repair pits at
concentrations ranging from 503 to 2345 ppm.
Ground Water
During the RI a hydrogeologic investigation was designed to
evaluate the ground water quality and movement in the aquifer
beneath the rail yard and the study area and determine the
concentration of PCBs in ground water. A total of 25 monitoring
wells were installed within the study area during the RI. As
shown in Figures 8, 9, and 10, most of the wells were located in
the vicinity of the rail yard car shop, but additional wells were
installed in the commercial area south of the rail yard and north
of the rail yard at the headwaters to Cedar Hollow, Hollow, and
North Valley tributaries. Two rounds of camples were analyzed.
During the RI, water table elevation measurements were taken in
the on-site wells; No. 2 fuel oil was detected in well 10 near
the car shop building. In July 1990, a fuel oil recovery and
ground water recovery system was installed at the rail yard and
is currently in operation. This system recovers approximately
250 gallons of fuel oil annually. Two rounds of samples were
analyzed for PCBs. Additional ground water samples were analyzed
for total petroleum hydrocarbons, benzene, toluene, ethylbenzene
and xylene (BTEX compounds). PCBs were not detected in ground
water outside of the vicinity of the car shop and were determined
to be present belov the level of quantification in veils
containing fuel oil, probably due to cross contamination with the
fuel oil which is known to mobilize PCBs. The concentration of
BTEX compounds reported in the RI ranged from 0.0037 ppm to 0.085
ppm and total petroleum hydrocarbons ranged from 0.036 to 0.87
ppm.
As part of the RI and in order to determine the extent and
concentration of PCBs and fuel oil constituents in the subsurface
soil profile, split-spoon samples were collected for PCBs and
total petroleum hydrocarbon (TPH) quantification. In wells that
did not contain phase-separate fuel oil, ground water was sampled
and analyzed for PCBs, TPH, and benzene, toluene, ethylbenzene,
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and xylene (BTEX) . A total of 25 soil borings were completed
near the car shop and east of the area of the above-ground fuel
oil tanks at a maximum depth of 20 feet. These borings were used
to identify the lateral and vertical extent of affected soils in
the area of concern. RI sampling results are highly variable in
terms of the lateral and vertical extent of hydrocarbon
contamination. The maximum levels of total petroleum
hydrocarbons exceed 10,000 ppm.
Biota
A comprehensive investigation to characterize terrestrial and
aquatic biota as well as investigate any wetland ecosystems
within the study area was completed as part of the RI. Three
categories of land uses have been established:
residential/suburban, successional woodlands, and estate-type
farms. A field reconnaissance was conducted to identify the
dominant species of concern within each category* This
investigation also identified fauna that may potentially migrate
into, or otherwise enter, the area encompassing the RI study
area.
Fish samples were collected during the RI from a total of five
stream stations. At each station three composite samples were
collected. The first sample was a trout fillet composite, the.
second was a sucker fillet composite, and the third was a sucker
whole grind composite. Benthic invertebrate samples were
collected from Little Valley and Valley Creeks. Because no
freshwater clams or snails were observed, worms (oligocheates)
were selected as an alternate species. Worms were collected from
a total of eight stations in Little Valley and Valley creeks
(Refer to Figures 11, 12, and 13).
A wetlands assessment was conducted in the study area as part of
the RI. Wetland ecosystems are important for reducing flood
hazards, reducing erosion and the situation of streams and
rivers, providing habitats for plants and animals (including
rare, threatened, and endangered species), and helping to
maintain water quality by providing a natural filtration system
for contaminants and suspended particles. The study area
consisted of approximately 400 acres located in the Piedmont
Uplands. An initial survey resulted in the division of the area
into three aajor vegetation units: a forested slop* unit,
grassland unit, and a flood-plain forest unit. Within these
units, eight wetland observation areas were chosen. Wetland
inclusions occurred within all three units as narrow bands of
riparian wetlands associated with the local water courses.
An area of wooded slope occurs immediately north of the"rail
yard, extending approximately a half-mile to a nearby level area
that has previously been cleared for agricultural use and the
installation of electric power transmission line towers. The
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Cedar Hollow, Hollow, and North Valley road tributaries draining
the rail yard carry surface water topographically downslope to
the north in this area. Hydrologic indicators of wetland
conditions were generally not encountered in the forested slope
unit. An exception to this situation was found in an area
between the Cedar Hollow and Hollow tributaries. An area of
forested wetland resulting from a ground water seep approximately
mid-way downslope was encountered. Because the seep originates
at mid-slope, it is not receiving surface drainage from the rail
yard and, therefore, is not expected to be impacted by
contamination.
Based on the results of the routine determination, the majority
of the wooded slope unit is not a jurisdictional wetland.
Neither the hydrotropic vegetation nor the wetland hydrology
criterion are met. The wetland areas associated with the water
courses in the forested slope unit are more limited than would be
expected.
Downstream of the forested slope unit 'is an area of nearly level
terrain approximately 500 feet wide which has been cleared of
trees. It appears that the land was at one time used for
agricultural purposes. The grassland unit now serves as an
electrical transmission line right-of-way. The original forest
vegetation has been replaced with cultivated grasses interspersed
with herbaceous plants.
The three tributaries draining the rail yard traverse this area.
Two wetland observation areas were chosen in the grassland unit:
one adjacent to Hollow tributary and one adjacent to Cedar Hollow
tributary. As a result of the greatly decreased slope relative
to the wooded slope region, stream flow is significantly lessened
in the grassland unit. Wetland vegetation associated with the
water courses is readily apparent. Soils were inundated with
several inches of water or were saturated for distances
approximately 25 feet from the water channels.
While the grassland unit as a whole is not a wetland, wetland
inclusions associated with the tributary flows have been
identified by the presence of hydrophytic vegetation, hydric
soils, and evidence of wetland hydrology. The riparian wetland
zones associated with the tributaries in the grassland unit are
more extensive than those observed in the wooded slope unit as a
result of the decreased stream flows in the level terrain.
Floodplain forest can be found downstream of the grassland unit
and extend approximately half a mile to Little Valley Creek. The
floodplain forests are dominated by different environmental
conditions. Hydrophytic vegetation criterion were not met. In
several areas it was not possible to obtain a soil sample
suitable for hydric soil determinations because the substrate was
composed almost completely of fine schist material. No evidence
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of wetland hydrology was observed in the floodplain forest unit.
Flora and Fauna
Flora and fauna were characterized in the study area. In general,
there.is a mix of residential areas, estate-type farms/farmland,
commercial/light industrial, and successional woodlands.
Approximately fifty percent of the area along the tributaries
between the rail yard and Little Valley Creek is comprised of
residential/suburban development. Besides some light industrial
parks bordering North Cedar Hollow Road, the remainder of the
area is mostly successional woodland areas. The area along
Little Valley Creek, bordered by the tributaries (from the Paoli
Rail Yard) and Valley Creek, is almost exclusively estate-type
farms, with patches of woodlands.
VI. SUMMARY OF SITB RISKS
Public Health Studies
In 1987, the Agency for Toxic Substances and Disease Registry
(ATSOR) conducted an epidemiologic investigation to study the
possible effects of PCB exposure on 89 persons living near the
Paoli Rail Yard Site. Blood samples were collected from
residents in the more contaminated areas adjacent to the rail
yard and compared with a control group farther away and less
likely to be exposed to PCBs. No statistically significant
difference was observed between PCB blood serum levels in the
control and the non-control group. Some of the persons tested
living in the more contaminated areas also worked at the rail
yard. Among the persons tested, age was the only variable that
correlated well with serum PCB levels; the older the person, the
higher the PCB blood serum levels.
EPA Risk Assessment
EPA prepared a baseline risk assessment (RA) for the Paoli Rail
Yard Site in order to characterize the current and potential
threats to human health and the environment and to quantify risks
from PCBs. As part of the RI/RA, a baseline risk assessment was
also prepared by GTI for SEPTA, Amtrak, and Conrail. EPA has
chosen to rely primarily on its own human health and
environmental risk assessment due to deficiencies in the rislc
assessment contained in the RI/RA. Table 2 provides a discussion
of the key tarns used in the risk assessment described in the
ROD. The EPA risk assessment consisted of a toxicity assessment,
an exposure assessment, and a risk characterization. ~
current land zoning for the rail yard and the immediate vicinity
surrounding the rail yard is commercial. Land use north of the
Site beyond West Central Avenue is residential. According to
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local zoning ordinances and information received from Tredyffrin
Township and Willistown Township, future land use for the rail
yard will not be residential.
The risks to human health are quantified by using cancer potency
factors (CPFs) for carcinogenic contaminants and reference doses
for noncarcinogenic contaminants. CPFs have been developed by
EPA's Carcinogenic Assessment Group for estimating excess
lifetime cancer rislcs associated with exposure to potentially
carcinogenic chemicals. CPFs, which are expressed in units of
(mg/kg-day)-1 are multiplied by the estimated intake of a
potential carcinogen, in mg/kg-day, to provide an upper-bound
estimate of the incremental or excess lifetime cancer risk
associated with exposure at that intake level. The term "upper
bound" reflects the conservative estimate of the risks calculated
from the CPF. Use of this approach makes underestimation of the
actual cancer risk highly unlikely. Cancer potency factors are
derived from the results of human epidemiological studies or
chronic animal bioassays to which animal-to-human extrapolation
and uncertainty factors have been applied.
Populations at risk include:
(1) Persons who mav work at the rail yard now and in the
future. The primary routes of exposure would be inadvertent
ingestion and dermal absorption of PCBs by adults. The
occupational setting may be either commercial or industrial.
(2) Persons who live j.n the residential area in the vicinity of
the rail yard. The primary routes of exposure would be
inadvertent ingestion and dermal absorption of PCBs by adults and
children.
(3) Persons who consume fish from Little Valley Creek and Valley
Creek contaminated with PCBs. The primary route of exposure
would be ingestion.
Contaminants of Concern
Two primary contaminants of concern, PCBs and benzene, were
selected in the ROD based upon their toxicity, mobility and
persistence in the environment, and potential health risks..
Because of the extremely high levels of PCBs detected at the rail
yard (maximum of 6,000 ppm) and their carcinogenic potential,
PCBs are a primary contaminant of concern and evaluated in the
risk assessment. Concentrations of PCBs detected in the study
area are shown in Table 1.
The specific contaminants of concern in the ground water are BTEX
compounds (benzene, toluene, ethylbenzene, and xylene). Because
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benzene is a known human carcinogen and has been detected at
concentrations in ground water that exceed the MCL established
under the Safe Drinking Water Act, benzene was selected as a
primary contaminant of concern. Benzene has been detected in the
ground water at the rail yard in concentrations up to n ug/1.
Ground water sampling results for PCBs were reported as
laboratory values less than the reliable detection limit but
possibly greater than zero. These values are below the
quantification limit which1 is the lowest level at which a
chemical can be accurately quantified.
Toxicity Assessment;
Polychlorinated biphenyls, or PCBs, represent a class of 209
individual chlorinated hydrocarbon compounds that contain a
variable number of substituted chlorine atoms on the biphenyl
ring. PCBs are man-made chemicals and are classified as
suspected human carcinogens based on scientific data from
laboratory animals. The PCBs most frequently detected within the
study area are Arochlor 1254 and 1260,*with Arochlor
predominantly detected. Benzene is classified as a human
carcinogen based on epidemiological studies. Ethylbenzene,
toluene and xylene are not classified as carcinogens.
Exposure Assessment
The EPA risk assessment identified potential exposure pathways
for incidental soil ingestion and fish consumption. There are
currently persons on-site at the rail yard who work in the train
repair building car shop and in the rail yard. Some workers may
be expected to remain on-site after the rail yard is closed for
routine maintenance and other related work. If the future
occupational setting is considered to be commercial rather than
industrial, then office workers or other similar type workers in
a commercial work place would be expected to come in contact with
contaminated soil and dust. There are children and adults who
reside in the area closest to the rail yard and will be exposed
to soil containing PCBs. PCBs were also detected in fish in
nearby Little Valley Creek and Valley Creek.
The following exposure routes involving the designated population
were considered in EPA's baseline risk assessment. Exposure
assumption* are documented in the EPA "Risk Assessment Guidance
for Super fund: Human Health Evaluation Manual1* and the
supplemental guidance "Standard Default Exposure Factors" (OSWER
Directive 9285.6-03).
Extensive sampling has been conducted of PCB concentration in
soil at the rail yard and in the residential community. PCB
concentrations in rail yard soil in the vicinity of the car shop
and high use track areas are in the range of 1,000 to 6,000 ppm
PCBs. Because of earlier cleanup operation and excavation of the
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residential neighborhood, PCS concentrations in residential soil,
as of 1989, are in the range of less than 1 ppm to approximately
20 ppm.
1) Ingestion of contaminated soils from the rail yard
The exposure pathway for rail yard soils is based on ingestion of
PCS contaminated soil for an adult who works in a
commercial/industrial setting for 5 days a week for 50 weeks per
year (250 days total) for a period of 25 years. Adults are
assumed to be routinely exposed to contaminated soil or dust, and
exposure is assumed to be lower than under an industrial
scenario. This exposure scenario is considered reasonable based
on current use and future expected use which may be a commercial
setting.
2) Ingestion of contaminated soils from the residential area
The exposure scenario for residential soils is based on frequent,
repeated contact with contaminated soi'ls by both children and
adults since children play in the area and both inhalation and
ingestion of PCB contaminated soil may be considered likely to
occur. The exposure scenario assumes a year round exposure to
PCB of 350 days/year and EPA guidance specifies a combined soil
and dust ingestion rate of 200 mg/day for children (6 years of.
exposure) and 100 mg/day for adults.
3) Consumption of fish
This exposure pathway is considered relevant because PCB
contamination at the rail yard has impacted Little Valley and
Valley Creeks which supply a consistent supply of trout and
other edible fish. A ban on fish consumption is now in effect as
discussed in the ROD. An exposure scenario of 0.054 kg/meal for
a 30 year duration has been assumed.
4) Inhalation of contaminated air
This exposure scenario considers the risk for adults at the rail
yard and for adults and children (combined exposure) in the
residential neighborhood immediately adjacent to the rail yard
based on inhalation of particulates which are contaminated with
PCBs. EPA has employed the model of Cowherd, et. al. using EPA
guidance document "Rapid Assessment of Exposure to Particulate
Emissions froa Surface Contamination Sites" (EPA/600/8-85/002,
February, 1985. The assumptions used to calculate a chronic
daily impact (GDI) for persons working at the rail yard include a
PCB inhalation rate of 0.83 m3/hour, an exposure time of 8
hours/day, and exposure frequency of 250 days/year for 25 years.
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5) Ground Water
No risk assessment was performed as part of the PRP RI/RA nor as
part of the EPA risk assessment, since no evidence existed that
contaminants of concern in the ground water have migrated
off-site of the rail yard. In addition, residents in the area
are supplied with public drinking water. EPA has recently become
aware of three residential dwellings downgradient of the rail
yard which may still be using ground water for drinking purposes.
As part of the remedial design phase of the remediation, EPA
intends to conduct sampling and analysis of these wells and will
take appropriate action to minimize any health endangerment if
any level of contaminant were to exceed Agency action levels.
Table 3 contains a summary of the assumptions used in the
baseline risk assessment.
Risk Characterization
The baseline risk assessment conducted*by EPA evaluated the
potential carcinogenic risks posed by PCBs in the various
exposure media. Potential human health problems from PCB
exposure are identified by calculating the carcinogenic risk
level. For example, a 1 x 10~6 level indicates one additional
chance in one million that an individual will develop cancer
above the expected normal rate of 250,000 in one million.
Remedial action is generally warranted when the calculated
additional carcinogenic risk level exceeds 1 x 10~4, meaning that
more than one or more additional persons out of 10,000 is at risk
of developing cancer caused by a lifetime exposure to PCBs.
The incremental cancer risk from the exposure scenarios described
above were calculated as follows:
Persons who work at the Rail Yard-The lifetime excess cancer risk
associated with exposure from ingestion of PCBs in soil for
persons who work at the rail yard based on current levels of PCB
contaminated soil is in the range of 1.6 x 10"3 to 2.3 x 10"3.
Excavation and treatment of soils with a PCB concentration of 25
ppm or greater will reduce the risk to a 3.5 x 10"5 incremental
cancer risk level. The lifetime excess cancer risk from
inhalation of PCB-contaminated particles based on current
conditions is 2.8 x 10*4.
Residential Adults and Children-The lifetime excess cancer risk
associated with exposure to PCBs in residential soil based on
current conditions is 5.5 x 10*5 for children and 1.7 x 10"5 for
adults. For residential exposure, a PCB concentration Off 2 ppm
approximates a 10~s incremental cancer risk level for children
and for adults. The lifetime excess cancer risk from inhalation
of PCB-contaminated particles based on current conditions is 5.6
x 10~5.
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Environmental Risks
The PCB levels in sediments in the three tributaries to Little
Valley Creek (CHR, HR, and NVR), Little Valley Creek, and Valley
Creek.were reviewed relative to the ecological effects and
environmental risks using field data and information of toxicity
of PCBs from the literature.. PCBs were generally not detected in
surface water with the detection limit used in the RI/RA. Based
on data from the RI/RA, PCBs were detected in sediments in the
three tributaries to Little Valley Creek at levels exceeding 10
ppm, ranged from undetected to 1.9 ppm in Little Valley Creek,
and undected to less than 1 ppm in Valley Creek. EPA believes
that these levels may change over time due to sediment transport
and that additional baseline sampling will be necessary
immediately prior to remediation.
The environmental risk associated with these levels of PCBs in
sediments is expected to be of concern because (1) the
contaminated areas provide habitat resources for wildlife; (2)
PCB concentrations in sediment exceed concentrations at which
toxic effects to aquatic organisms have been observed; and (3)
bioconcentration of PCBs can occur directly through exposure to
contaminated sediment and water or indirectly through consumption
of aquatic organisms.
In assessing environmental risk, EPA did not rely on the
conclusions of the RI/RA report because the Agency believes the
technical conclusions of the RI/RA were limited in scope, and
because the "weight-of-evidence" on PCB toxicity from the
literature was not considered in the RI/RA and is necessary to
evaluate environmental risks. In particular, EPA has relied on
information from the scientific literature in the Administrative
Record (see "A Discussion of PCB Target Levels in Aquatic
Sediments" by L.J. Field and R.N. Dexter), and information in the
Administrative Record from the Pennsylvania Fish Commission and
U.S. Department of Interior which recommend a cleanup standard of
1 ppm PCBs in sediment. The publication entitled "A Discussion
of PCB Target Levels in Aquatic Sediments" generally supports a
target sediment level in the range of 0.1 to 1.0 ppm based on
bioaccumulation and toxicity data. The actual cleanup standard
must take into account the characteristics of the contaminated
area and the potential environmental impacts of the remediation
activity. The 1 ppa cleanup standard is considered a protective,
quantifiable level by State and Federal regulatory agencies which
can be achieved without significant adverse effects upon the
aquatic system.
There is no documentation of federal endangered species within
the immediate study area. However, Valley Forge National Park,
through which Valley Creek flows, is possibly home for three
Pennsylvania endangered species of bird - the bald eagle,
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peregrine falcon, and osprey. A number of other threatened or
imperiled bird species in Pennsylvania have been sighted in the
park.
Valley Creek contains a self-sustaining trout population and is
classified as a cold water fishery. The Pennsylvania Fish
Commission has categorized the creek as a Class A trout stream,
the highest stream class recognized in the state. Some of the
more common species of fish present in Valley Creek are brown
trout, white sucker, rock bass, smallmouth bass, and bluegill.
PCB levels in fish from Valley Creek have historically exceeded
the Food and Drug Administration (FDA) level for human
consumption of 2 parts per million ("ppm") [see 21 C.F.R. §
109.30]. An analysis in 1986 by Pennsylvania DER of brown trout
taken from Valley Creek inside Valley Forge National Park
indicated PCB levels of 2.8 and 4.5 ppm (whole trout) and 2.7 and
3.7 ppm (trout fillets). In 1989, Pennsylvania DER reported PCB
levels in brown trout fillets at 2.5 ppm in Valley Creek and 2.8
ppm in Little Valley Creek. These PCB concentrations exceed the
levels reported in the RI/RA report. Based on 18 fish samples
collected from Little Valley and Valley Creeks during the RI, the
average PCB concentration in trout fillets was 0.9 ppm, 1.26 ppm
in sucker fillets, and 2.74 ppm in whole suckers.
EPA's baseline risk assessment for trout fillets and sucker
fillets downstream of the Site indicates an incremental cancer
risk of 1.1 x 10"3 to 1.6 x 10"3 for fish consumption.
Consumption of fish from Valley Creek is prohibited under State
law and fishing is allowed only on a catch-and-release basis.
Actual or threatened releases of hazardous substances from this
Site, if not addressed by implementing the response action
selected in this ROD, may present an imminent and substantial
endangerment to public health, welfare, or the environment.
VTI. REMEDIAL ACTIOM OBJECTIVES
Soil and Sediments
The remedial action objective is source control of contaminated
soils and sediments to protect human health and the environment
from exposure through direct contact and incidental ingestion.
This objective will be accomplished through excavation and •
treatment of soils and sediments that represent a principal
threat and exceed risk based action levels and cleanup standards.
The Paoli Rail Yard is currently zoned for commercial land use
but land use may be currently characterized as industrial. After
rail yard activities are suspended in 1994 / the land used will be
non-residential based on current and projected future zoning
requirements. Residential use will be prohibited through
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institutional controls. EPA has chosen an action level of 25 ppm
PCBs for the rail yard based on the Agency's risk assessment.
That action level is also consistent with EPA's "Guidance on
Remedial Actions for Superfund Sites with PCB Contamination"
(OSWER Directive No. 9355.4-01, August, 1990 which recommends an
action level in the range of 10 to 25 ppm for industrial sites).
The remedial action objective of excavation and treatment of soil
with PCBs exceeding 25 ppm will achieve an incremental cancer
risk level of 3.5 x 10". This action level is protective of
human health and the environment and will be consistent with
future land use. EPA believes that for purposes of establishing
cleanup standards it is not appropriate to treat the rail yard as
a residential site in order to achieve a cleanup standard
consistent with residential use.
The residential area adjacent to the rail yard has been
contaminated with PCBs through erosion and soil deposition from
the rail yard. Previous removal actions in the residential area
excavated residential soils above 50 ppm PCBs. EPA has set a
cleanup standard of 2 ppm for residential soils based on the
Agency's risk assessment for exposure of children and adults to
PCB-contaminated soil. An average PCB soil concentration of 2
ppm per individual property calculates to approximately a
1 x 10~S incremental cancer risk level. EPA believes this is a
protective, quantifiable residual level for PCBs in residential
soil.
Streams and tributaries in the study area will be excavated to
achieve a cleanup standard of 1 ppm PCBs in sediments. This level
is consistent with recommendations of the U.S. Department of the
Interior (DOI), the Pennsylvania Fish Commission, and a
compilation of technical documents published by the U.S.
Department of Commerce, Ocean Assessments Division, entitled "A
Discussion of PCB Target Levels in Aquatic Sediments". This level
is consistent with EPA OSWER Directive No. 9355.4-01 entitled
"Guidance on Remedial Actions for Superfund Sites with PCB
Contamination," August 1990. The available chemical and
environmental monitoring data from the study area, along with
weight-of-evidence indicating that PCBs can bioaccumulate in the
food chain and have adverse impacts on aquatic life at even lower
concentrations in sediment, support using this standard.
In addition, EPA will require that additional stream studies be
performed a* part of the remedial action. These studies will
ascertain the exact extent of contaminated stream corridor above
the cleanup level.
Rail Yard Buildings and Structures
EPA requires that SEPTA employees continue to implement the
worker protection program to minimize direct exposure to PCB
contamination and incorporates that document into this Record of
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Decision. EPA has set a standard for decontamination of surfaces
of the rail yard car shop and related buildings and structures
containing PCBs in excess of 10 ug/100 cm2 based on the PCB Spill
Cleanup Policy (40 C.F.R. §761.120) to protect site workers from
direct exposure and contact with PCBs.
Ground Water
The ground water aguifer underneath the Paoli Rail Yard Site is
classified as a Class IIA aguifer, a current source of drinking
water. Ground water sampling results for PCBs were reported as
laboratory values less than the reliable detection limit but
possibly greater than zero. These values are below the
quantification limit which is the lowest level at which a
chemical can be accurately quantified. PCBs were reported below
the level of quantification in wells containing fuel oil,
probably due to cross contamination with the fuel oil which is
known to have historically leaked into the ground water
underneath the rail yard in the vicinity of the car shop may act
to dissolve and carry PCBs into the ground water. Pumping of
ground water contaminated with fuel oil, ground water treatment,
and fuel oil recovery system is currently being implemented at
the rail yard.
Benzene has been detected in ground water in the vicinity of the
rail yard car shop building at levels that exceed the MCL. The
source of the benzene is believed to be the fuel oil
contamination. The maximum detected concentration for benzene is
11 ppb since the start of the ground water and fuel oil recovery
system. The remedial action objective is to recover fuel oil to
the maximum extent practicable and to restore contaminated ground
water to the MCL for benzene (5 ug/1) as required under the Safe
Drinking Water Act ("SDWA"), 42 U.S.C. SS 300f-300j and the
regulations at 40 C.F.R. S 141.61, or to background concentration
for benzene, whichever is more stringent. Thus, the currently
on-going pump and treat remediation is incorporated into this ROD
as a means of containing and removing the fuel oil contamination
constituents.
VTII. PgaCRIPTIOM Of ALTBMIATIVgfl
A feasibility study (FS) was conducted to identify and evaluate
remedial alternatives applicable to the scope and role of the
response action based on effectiveness, implementability, and
cost. Treatability studies were conducted on several
technologies for treating PCBs in soil that measured the
effectiveness of these technologies. The alternatives determined
to be most applicable were then evaluated and compared to nine
criteria required by the National Contingency Plan (NCP). The
NCP requires a No Action alternative be evaluated as a point of
comparison for other alternatives.
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Treatability Study Results
As part of the FS, treatability studies were conducted on several
technologies to demonstrate the viability of the technology, to
determine whether the technology can reasonably be expected to
meet cleanup standards for the Site, and to determine additional
testing required for full-scale design. The treatment
technologies evaluated were incineration, thermal desorption,
KPEG dechlorination, OCR dechlorination, solvent extraction,
stabilization/solidification, and bioremediation. As a result of
the FS screening process, seven soil treatment options were
retained for further evaluation using treatability studies.
Bench-scale treatability studies were conducted using untreated
soil from the rail yard on all of these technologies except
incineration which is a proven technology for treatment of PCB
contaminated wastes. The treated residual levels were compared
against the equivalent performance standard of 2 ppm; other
performance criteria were also evaluated. As described in OSWER
Directive No. 9355.4-01 entitled "Guidance on Remedial Actions
for Superfund Sites with PCB Contamination", August 1990, PCB-
contaminated material can be treated by an alternative method
provided that the treatment can achieve a level of performance
equivalent to an incinerator or a high efficiency boiler. EPA
guidance indicates that an equivalent level of performance for an
alternate method of treatment of PCB-contaminated material is
demonstrated if it reduces the level of PCBs to 2 ppm or less
measured in the treated residual.
In summary, the technologies that proved to be most favorable
were stabilization/solidification and KPEG dechlorination,
although treatability studies indicated that the KPEG process
would create material handling/operational difficulties. Thermal
desorption and solvent extraction did not meet performance
criteria. Thermal desorption also increased the leachability of
metals from soil to the extent that Toxicity Concentration
Leaching Procedure ("TCLP") test results showed that leachable
lead in the treated soil exceeded the EPA regulatory level.
Bioremediation was considered effective in treating total
petroleum hydrocarbons in fuel oil but not PCBs. Results of the
OCR process were never completed. The stabilization/
solidification study was conducted using four different
stabilizing agents to evaluate the physical stability of each.
The TCLP results for both the untreated soil and the solidified
material shoved that PCB concentrations in the leachate was in
the range of 1 to 3 ppb PCBs. The rail yard ash and cinder-fill
material also acts as a binder and aggregate for the solidified
material.
Using results from the treatability studies, the KPEG process,
incineration, and stabilization/solidification, were retained
for further analysis as source control technologies.
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This ROD addresses five distinct areas of study for which each of
the alternatives retained are described. These areas are
segregated according to the breakdown shown below with sub-
elements for some of the complex alternatives.
Rail Yard soj],
1. No action .
2. Institutional "controls
3. Containment of contaminated soils
4. Excavation and on-site treatment of contaminated
soils with PCB concentrations exceeding 500 ppm
5. Excavation and on-site treatment of contaminated
soils with PCB concentrations exceeding 25 ppm
6. Excavation, on-site treatment of contaminated soils,
and containment
7. Excavation and off-site disposal
Residential and other soil
•
1. No action
2. Excavation and treatment of residential soils
Groundwater treatment and fuel oil recovery
Rail Yard buildings and structures
1. No action
2. Containment or encapsulation
3. Decontamination
4. Decontamination and Demolition
Stream sediments
l. No action
2. Containment
3. Excavation and treatment of sediments with PCB
Concentrations exceeding 10 ppm
4. Excavation and treatment of sediments with PCB
concentrations exceeding -l ppm
ALTERNATIVE* FOR RAIL YARD SOIL
For each of the alternatives discussed for the rail yard
soils it im envisioned that rail yard operations will have ceased
at this location and rail tracks and ties would be removed and
disposed of prior to construction of any of the remedies- Most
of the areas of excavation are underneath the railroad tracks
which are currently in use and, therefore, the tracks and ties
must be removed. The tracks would be steam washed and sent to an
off-site disposal or recycling facility. The railroad ties would
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be sent to an appropriate off-site disposal facility.
Decontamination and disposal would meet TSCA requirements at 40
CFR §5 76i.20(c) and 76i.60(a).
Alternative 1—No Action
Capital Cost: -0-
Annual O&M Costs: $57,960
Present Worth Costs: $546/431
Implementation Time frame: None
The No Action alternative is considered in the detailed analysis
to provide a baseline to which other remedial alternatives can be
compared. This alternative would include no further action to
remove, remediate or contain rail yard soils other than routine
monitoring and maintenance activities. Because this alternative
will result in contaminants remaining onsite, CERCLA $ 121(c)
requires that a Site review be conducted every 5 years to monitor
the effectiveness of this alternative^ This alternative could be
implemented immediately. This alterna'tive would not meet
action-specific ARARs which require remediation or landfilling of
soils greater than 50 ppm under the TSCA disposal requirements
set forth at 40 C.F.R. $ 761.60. There are no location-specific
or chemical-specific ARARs for this alternative.
Alternative 2—Institutional Controls
Capital Cost: $10,000
Annual O&M Costs: $57,960
Present Worth Costs: $556,431
Implementation Time frame: None
Institutional controls would include deed restrictions to
prohibit use of the property for residential or food growing
purposes. Routine monitoring and maintenance activities would
continue as described in Alternative 1. Because this alternative
will result in contaminants remaining onsite, CERCLA $ 121(c)
requires that a Site review be conducted every 5 years to monitor
the effectiveness of this alternative. This alternative could be
implemented immediately. This alternative would not meet
action-specific ARARs which require remediation or landfilling .of
soils greater than 50 ppm under the TSCA disposal requirements
set forth at 40 C.F.R. S 761.60. There are no location-specific
or chemical-specific ARARs for this alternative.
Alternative 3—Containment of Contaminated Soils
Capital Cost: $10,331,485 '
Annual O&M Costs: $103,250
Present Worth Costs: $11,304,723
Implementation Time frame: 6 months
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Under this alternative, a 12-inch soil cover or equivalent would
be placed over approximately 15 acres of rail yard property
having PCB concentrations in excess of 25 ppn. Clean soil would
be used from off-site sources and the soil cover graded and
suitably vegetated. Appropriate drainage structures would be
constructed to control surface runoff from the area. Most of the
areas identified as exceeding 25 ppn PCB concentration are in the
vicinity of the railroad" tracks. It is anticipated that in the
northern portion of the Site where track areas are near
residential properties along Central Avenue, the soil cover would
extend to the rail yard Site boundary adjacent to the residential
properties to ensure that contaminated areas are adequately
contained and to prevent runoff onto residential properties.
Institutional controls would prohibit the Site for residential
use as described in Alternative 2.
Because this alternative will result in contaminants remaining
onsite, CERCLA $ 121(c) requires that a site review be conducted
every 5 years to monitor the effectiveness of this alternative.
Location-specific ARARs include the Pennsylvania Erosion Control
Regulations, 25 PA Code SS 102.1-102.5, $$ 102.11-102.13, 102.22-
102.24. This alternative would not meet action-specific ARARs
which require remediation or landfilling of soils greater than 50
ppm under the TSCA disposal requirements set forth at 40 C.F.R.
S 761.60. There are no chemical-specific ARARs for this
alternative.
Alternatives 4A. 4B. 4C—Excavation and On-site Treatment .°f
Contaminated Soils with PCB Concentrations Exceeding 500 pom
Capital Cost: $7,367,800 to $13,779,120
Annual O&M Costs: $57,969 to $110,950
Present Worth Costs: $8,413,620 to $14,324,450
Implementation Time frame: 6 months
These alternatives involve excavation and treatment of
approximately 8,000 cubic yards of contaminated soil with PCB
concentrations exceeding 500 ppm. A PCB concentration of 500 ppm
represents an excess cancer risk between 10"3 and 10*4 based on
worker exposure. Most of the areas of excavation are underneath
the railroad tracks, requiring the tracks and ties be removed.
The tracks will be steam washed and sent to an off-site disposal
or recycling facility. The ties will also be sent to an off-site
disposal facility. Testing of the railroad tracks for any
remaining PCBs will occur after the steam washing process and
before being sent to a recycle or disposal facility (other than
an approved PCB waste disposal site) in accordance with-40 C.F.R.
SS 76l.20(c) and 761.60(a).
Three different soil treatment technologies that were retained
and evaluated from the technology screening for treatment of
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contaminated soils are described below. Institutional controls
would prohibit Site use for residential use as described in
Alternative 2. Because these alternatives will result in
contaminants remaining onsite, CERCLA § 12l(c) requires that a
Site review be conducted every 5 years to monitor the
effectiveness of this alternative.
PCBs alone are not a RCRA hazardous waste. The contaminated PCB
soil is not a RCRA characteristic waste. PCB-contaminated soils
are exempt from 40 CFR § 268 Land Disposal Restrictions by 40 CFR
§ 261.8. Therefore, the RCRA prohibition on land disposal of
hazardous waste and RCRA closure requirements are not ARARs for
this Site. Any waste material or product which may be generated
during remediation activities, other than PCBs, which is
determined to be a RCRA characteristic waste will be disposed in
accordance with RCRA Subtitle C, Hazardous Waste Management
Requirements, 40 C.F.R. Parts 262, 263 and 264.
The Pennsylvania Hazardous Waste Regulations, 25 PA Code Chapts.
260-264 do not apply since PCBs are not a State listed hazardous
waste. Location-specific ARARs include the Pennsylvania Erosion
Control Regulations, 25 PA Code §§ 102.1-102.5, §§ 102.11-102.13
and §§ 102.22-102.24. This alternative would not meet
action-specific ARARs which require remediation or landfilling of
soils greater than 50 ppm under the TSCA disposal requirements
set forth at 40 C.F.R. § 761.60. Other action-specific ARARs
include: TSCA, 40 C.F.R. § 761.20(c) relating to distribution of
PCBs in commerce; the TSCA chemical waste landfill requirements,
40 C.F.R. § 761.75 with the exception of those management
controls which are waived under CERCLA § 121(d)(4); and the
Pennsylvania Air Pollution Control Act, 25 PA Code §§ 123.1,
123.2, 123.41, 127.1, and 127.14. There are no chemical-specific
ARARs for this alternative.
Alternative 4A — Excavation and On—site Treatment with
Stabilization/Solidification;
Contaminated soil would be excavated, treated using a
stabilization/solidification process, and placed back on-site in
a containment cell. The excavated area would be backfilled with
clean soil, graded to contour, and revegetated. Erosion control
measures would be required during and after construction to
manage and control storm water runoff in accordance with the
State regulations.
Stabilization/solidification is a demonstrated treatment process
that involves the mixing of contaminated soil with specific
ratios of water, binder material, and other additives to modify
the physical and chemical properties in such a manner to cause
the contaminates to remain physically bonded to rigid aggregate
mixture. This process binds the contaminants into a solid matrix
which will immobilize the contaminants. A treatability study,
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utilizing this treatment process, was conducted during the FS
which revealed that the stabilized material reduced the migration
potential of PCBs. Despite immobilization, however, PCBs are
still present in the waste and are not destroyed, requiring
management controls to evaluate the long-term reliability of the
process. No air emissions or wastewater discharge is expected
from the process but air emissions could occur during handling of
excavated soil. See the.discussion of ARARs in Alternatives 4A,
4B and 4C, above, for those Federal and State laws that are
applicable or relevant and appropriate to the remedy. The
present worth cost is $8,413,620.
Alternative 4B - Excavation and On-site Treatment with KPEG
Dechlorination;
Contaminated soil would be excavated and treated on-site with a
reagent mixture in a tank. Chemical reagents prepared from
polyethylene glycols and potassium hydroxide have been
demonstrated to dechlorinate PCBs. The resulting treated slurry
would be separated and the treated soil would be returned to the
Site. The used chemical reagent would be recycled or disposed
off-site by incineration in a RCRA facility if determined to be a
RCRA waste. KPEG is a closed process and no air emissions or
waste gases would be expected. Erosion control measures would be
required during and after construction to manage and control
storm water runoff in accordance with the State regulations.
A treatability study conducted during the FS indicated that this
process will achieve a PCB concentration of 2 ppm in the treated
soil. However, during the treatability study it was observed
that large amounts of suspended particles were present in the
decanted reagent and that separation and removal of these
suspended particles would likely require special material
separation equipment and probably result in problems in process
operation which may render the process ineffective. See the
discussion of ARARs in Alternatives 4A, 4B and 4C, above, for
those Federal and State laws that are applicable or relevant and
appropriate to the remedy. The present worth cost of this
treatment option is $11,098/950.
Alternative 4C — Excavation and On—site Treatment with
Incineration;
Incineration is a wall demonstrated technology for treatment, of
PCBs. A mobile incinerator would be brought to the Site and the
contaminated soil would be excavated and incinerated on-site to
meet TSCA treatment requirements pursuant to 40 C.F.R.
$ 761.60(a). A trial burn would be required before implementing
this alternative. Incineration technology has demonstrated
greater than 99% destruction efficiency for PCBs. Waste
incinerator gas would require treatment prior to discharge.
Water from the incineration process would be treated off-site in
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a RCRA facility if required. Treatability studies conducted
during the FS indicate that residual treated soil would be a RCRA
characteristic waste based on TCLP analysis. Residual metals and
ash would be solidified to meet RCRA land disposal treatment
standards and placed on-site in a secure containment area.
Erosion control measures would be required during and after
construction to manage and control storm water runoff. See the
discussion of ARARs in Alternatives 4A, 46 and 4C, above, for
those Federal and State laws that are applicable or relevant and
appropriate to the remedy. In addition, this alternative would
meet action-specific ARARs regarding incineration set forth at 40
C.F.R. 5 761.70 requiring incineration of PCBs greater than 50
ppm. The present worth cost of this treatment option is
$14,325,450.
Alternatives 5A. 5B. and 5C—Excavation and On-site Treatment of
Contaminated Soils with PCB Concentrations Exceeding 25 ppra
Capital Cost: $18,204,275 to $29,165,600
Annual O&M Costs: $-0- to $138,250
Present Worth Costs: $19,507,375 to $29,165,600
Implementation Time frame: 24 months
These alternatives involve excavation and treatment of
approximately 28,000 cubic yards of contaminated soil with PCB.
concentrations exceeding 25 ppm, using one of the three treatment
alternatives evaluated under alternative 4. A PCB concentration
of 25 ppm represents approximately a 10~5 excess cancer risk
based on worker exposure.
Most of the areas of excavation are underneath the railroad
tracks, requiring the tracks and ties be removed. The tracks
will be steam washed and sent to an off-site disposal or
recycling facility. The ties will also be sent to an off-site
disposal facility. Testing of the railroad tracks for any
remaining PCBs will occur after the steam washing process and
before being sent to a recycle or disposal facility (other than
an approved PCB waste disposal site in accordance with 40 C.F.R.
§S 76l.20(c) and 761.60(a)).
Institutional controls would prohibit Site use for residential.
use as described in alternative 2. Under these alternatives,
approximately 3000 cubic yards of soil from the residential soil
removal program currently located on the rail yard property .in a
lined containment cell would also be treated.
Because these alternatives will result in contaminants remaining
onsite, CERCLA 5 121(c) requires that a site review be conducted
every 5 years to monitor the effectiveness of the alternative.
PCB-contaminated soils are exempt from 40 CFR $268 Land Disposal
Restrictions by 40 CFR $ 261.8 and are not a RCRA hazardous waste
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and therefore, the RCRA prohibition on land disposal of hazardous
waste and RCRA closure requirements are not ARARs for this Site.
Any waste material or product other than PCBs which may be
generated during remediation activities and which is determined
to be a RCRA characteristic waste will be disposed of in
accordance with RCRA Subtitle C, Hazardous Waste Management
Requirements, 40 C.F.R. Parts 262, 263 and 264. The Pennsylvania
Hazardous Waste Regulations, 25 PA Code Chapt. 260-264 do not
apply as PCBs are not a State listed hazardous waste. Location-
specific ARARs include the Pennsylvania Erosion Control
Regulations, 25 PA Code §S 102.1-102.5, 102.11-102.13 and
102.22-102.24. This alternative would meet action-specific ARARs
which require remediation or landfilling of soils greater than 50
ppm under the TSCA disposal requirements set forth at 40 C.F.R.
§ 761.60. Other action-specific ARARs include: TSCA, 40 C.F.R.
§ 761.20(c) relating to distribution of PCBs in commerce; the
TSCA chemical waste landfill requirments, 40 C.F.R. § 761.75 with
the exception of those management controls which are waived under
CERCLA S 121(d)(4); and the Pennsylvania Air Pollution Control
Act, 25 PA Code §S 123.1, 123.2, 123.41, 127.1, 127.12, and
127.14. There are no chemical-specific ARARs for this
alternative.
Alternative 5A - Excavation and On-site Treatment with
Stabilization/Solidification;
Contaminated soil would be excavated, treated using a
stabilization/solidification process, and placed back on-site in
a containment cell. The excavated area would be backfilled with
clean soil, graded to contour, and revegetated. Erosion control
measures would be required during and after construction to
manage and control storm water runoff.
Stabilization/solidification is a demonstrated treatment process
that involves the mixing of contaminated soil with specific
ratios of water, binder material, and other additives to enhance
the physical and chemical properties. Contaminants are bound
into a solid matrix as a result, immobilizing contaminants. A
treatability study was conducted during the FS. However, even
though PCB migration potential is minimized, the PCBs are still
present in the vast* and are not destroyed, requiring management
controls to evaluate the long-term reliability of the process.
Management controls will comply with the TSCA chemical waste
landfill requirements under TSCA 40 C.F.R. S 761.7S(b) with .the
exception of those management controls which are waived under
CERCLA S 121(d)(4). These include: the requirement for
construction of a chemical waste landfill in certain low
permeable clay conditions [40 C.F.R. 76l.75(b)(1)], the.
requirement to use a synthetic membrane liner [761.75(b)(2)], the
requirement for a ground water leachate collection system
[761.75(b) (7)],and the requirement that the bottom of the
landfill be 50 feet above the historic high water table
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[76i.75(b)(3)]. NO air emissions or wastewater discharge is
expected from the process but air emissions could occur during
handling of excavated soil. Erosion control measures would be
required" during and after construction to manage and control
storm water and sediment runoff. See the discussion of ARARs in
Alternatives 5A, 5B and 5C, above, for those Federal and State
laws Chat are applicable or relevant and appropriate to the
remedy. The present worth cost would be $19,507,375.
Alternative SB - Excavation and On-site Treatment with KPEG
Deehlorination;
Contaminated soil would be excavated and treated on-site with a
reagent mixture in a tank. Chemical reagents prepared from
polyethylene glycols and potassium hydroxide have been
demonstrated to dechlorinate PCBs. The resulting treated slurry
would be separated and the treated soil would be returned to the
Site. The used chemical reagent would be recycled or disposed
off-site by incineration in a RCRA facility if determined to be a
RCRA waste in accordance with RCRA Subtitle C, Hazardous Waste
Management Requirements, 40 C.F.R. Parts 262, 263 and 264. KPEG
is a closed process and no air emissions or waste gases would be
expected. Erosion control measures would be required during and
after construction to manage and control storm water runoff.
A treatability study conducted during the FS indicated that this
process will achieve a residual PCB concentration of 2 ppm in the
treated soil. However, during the treatability study it was
observed that large amounts of suspended particles were present
in the decanted reagent and that separation and removal of these
suspended particles would likely require special material
separation equipment and probably result in problems in process
operation which may render the process ineffective. See the
discussion of ARARs in Alternatives SB and 5C, above, for those
Federal and State lavs that are applicable or relevant and
appropriate to the remedy. The present worth cost of this
treatment option is $24/424,400.
Alternative 5C - Excavation and On-site Treatment with
Incinerationt
Incineration is a well demonstrated technology for treatment of
PCBs. A mobile incinerator would be brought to the Site and the
contaminated soil would be excavated and incinerated on-site- to
meet TSCA incineration requirements set forth at 40 C.F.R.
$ 761.70. A trial burn would be required before implementing
this alternative. Incineration technology has demonstrated
greater than 99% destruction efficiency for PCBs. Waste-
incinerator gas would require treatment prior to discharge.
Water from the incineration process would be treated off-site in
a RCRA facility if required. Treatability studies conducted
during the FS indicate that the treated residual soil would be a
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RCRA characteristic waste based on TCLP analysis and vould
therefore, be disposed of in accordance with the RCRA Subtitle c,
Hazardous Waste Management Requirements, 40 C.F.R. Parts 262, 263
and 264. Residual metals and ash would be solidified to meet
RCRA land disposal treatment standards and placed on-site in a
secure containment area. Erosion control measures would be
required during and after construction to manage and control
storm water. See the discussion of ARARs in Alternatives 5A, 5B
and 5C, above, for those Federal and State laws that are
applicable or relevant and appropriate to the remedy. The
present worth cost would be $29,165,600.
Alternatives 6A. 6B. and 6C—Excavation. On-site Treatment of
Contaminated Soils, and Containment
Capital Cost: $11,236,950 to $17,648,230
Annual O&M Costs: $103,600 to $138,250
Present Worth Costs: $12,540,090 to $18,624,740
Implementation Time frame: 12 months
•
Alternative 6 is a hybrid combination of Alternatives 2, 3, and
4. This alternative requires excavation and treatment of
approximately 8,000 cubic yards of contaminated soil with PCS
concentrations exceeding 500 ppm and containment of approximately
12.5 acres (20,000 cubic yards) of contaminated soil having PCB
concentrations between 25 ppm and 500 ppm using a 12-inch or
greater soil cover. The soil cover would be the same as
described in Alternative 3, including runoff controls and
adequate containment in the vicinity of residential properties.
Soils with PCB concentrations greater than 500 ppm would be
excavated and treated using one of the three treatment
alternatives evaluated in Alternative 4. Institutional controls
would prohibit Site use for residential use as described in
Alternative 2. Because these alternatives will result in
contaminants remaining onsite, CERCLA $ 121(c) requires that a
site review be conducted every 5 years to monitor the
effectiveness of this alternative. See the discussion of ARARs
in Alternatives 2,2 and 4 for those Federal and State laws that
are applicable or relevant and appropriate to the remedy.
Alternative 6A - Excavation. Treatment using
Stabilization/Solidification, and Containment:
This alternative vould be a combination of Alternatives 2, 3, and
4A. Treatment using stabilization/solidification would be
implemented as described in Alternative 4A. See the discussion
of ARARs in Alternatives 2, 3 and 4 for those Federal and State
laws that are applicable or relevant and appropriate to the
remedy. The present worth cost is $12,540,090.
Alternative SB - Excavation. Treatment using KPEG Deehlorination.
and Containment;
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This alternative would be a combination of Alternatives 2, 3, and
4B. Treatment using KPEG Dechlorination would be implemented as
described in Alternative 4B. See the discussion of ARARs in
Sections 2, 3 and 4 for those Federal and State laws that are
applicable or relevant and appropriate to the remedy. The
present worth cost is $15,398,280.
Alternative 6C - Excavation. Treatment using Incineration, and
Containment;
This alternative would be a combination of Alternatives 2, 3, and
4C. Treatment using incineration would be implemented as
described in alternative 4C. See the discussion of ARARs in
Alternatives 2, 3 and 4 for those Federal and State laws that are
applicable or relevant and appropriate to the remedy. The
present worth cost is $18,624,740.
Alternative 7 - Excavation and Off-site Disposal
Capital Cost: $26,808,830
Annual O&M Costs: -0-
Present Worth Costs: $26,808,830
Implementation Time frame: 24 months
This alternative involves excavation of approximately 28,000
cubic yards of contaminated soil with PCB concentrations
exceeding 25 ppm and transportation to an off-site TSCA permitted
landfill for disposal. Contaminated soil would be transported
off-site either using rail cars or trucks depending on the
location of the TSCA landfill. The estimated present worth cost
includes excavation, transportation, and landfill costs. Prior
to excavation, railroad tracks and ties would be removed as
previously described. Any waste material or product generated
during remediation activities which is determined to be a RCRA
characteristic waste will be disposed in accordance with RCRA
Subtitle C, Hazardous Waste Management Requirements, 40 C.F.R.
Parts 262, 263 and 264. The excavated material would be
backfilled with clean soil, revegetated, and graded to contour.
Erosion control measures would be required during and after
construction to manage and control storm water runoff.
Institutional controls would prohibit Site use for residential
use as described in Alternative 2. Because this alternative will
result in contaminants remaining onsite, CERCLA $ 121(c) requires
that a Sit* review be conducted every 5 years to monitor the
effectiveness of this alternative.
Location-specific ARARs include the Pennsylvania Erosion Control
Regulations, 25 PA Code SS 102.1-102.5, 102.11-102.13 and
102.22-102.24; Action-specific ARARs include: TSCA, 40 C.F.R. S
761.20(c) relating to distribution of PCBs in commerce; and the
Pennsylvania Air Pollution control Act, 25 PA Code SS 123.1,
123.2, 123.41, 127.1; 127.1 and 127.14. There are no
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chemical-specific ARARs for this alternative.
ALTERNATIVES POR RESIDENTIAL AND OTHER SOIL
Alternative 1—No Action
Capital Cost: -o-
Annual O&M Costs: -0-
Present Worth Costs: -6- •
Implementation Time frame: -0-
The No Action alternative would involve no further excavation of
soils from residential areas and properties. There are no
action-specific, chemical-specific, or location-specific ARARs
for this alternative.
Alternative 2—Excavation and Treatment of Residential Soils
Capital Cost: $1,196,000 to $1,606,753
Annual O&M Costs: -0-
Present Worth Costs: $1,196,000 to $1,606,755
Implementation Time frame: 6 months
Under this alternative, limited excavation of residential
properties and drainage areas is proposed based on sampling
conducted during the RI/FS. The goal of this remediation is to
achieve an average PCS concentration of 2 ppm for individual
residential properties. An average PCS concentration of 2 ppm is
equivalent to approximately a 10"' excess cancer risk for
residential exposure assuming no soil cover and is a protective,
quantifiable concentration for soil. This risk assessment level
satisfies EPA's "Guidance on Remedial Actions for Superfund Sites
with PCS Contamination," US EPA, OSWER Directive: 9355.4-01,
Office of Emergency and Remedial Response Hazardous Site Control
Division (OS-220), August 1990 which is a TBC for the Site;
Soil would be excavated to a depth of approximately one foot,
replaced with clean soil, and revegetated to original conditions.
The excavated soil would be returned to the rail yard property
and treated onsite. The exact location of excavation would be
determined after discussion with property owners. Most of the
property locations are along Central Avenue. The present worth
cost of treatment is based on excavation and treatment of
approximately 1000 cubic yards of soils but will vary depending
on the exact locations of excavation and the volume of soils
excavated.
Location-specific ARARs include the Pennsylvania Erosion Control
Regulations, 25 PA Code 5$ 102.1-102.5, 102.11-102.13, and
102.22-102.24. Action-specific ARARs include the Pennsylvania
Air Pollution Control Act, 25 PA Code 55 123.1, 123.2, 123.41,
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127.1, 127.12 and 127.14; and TSCA - Manufacturing, Processing,
Distribution in Commerce, and Use of PCBs and PCS Items, 40
C.F.R. 5761.20(c); TSCA Disposal Requirements, 40 C.F.R. §
761.60(a). There are no chemical-specific ARARs for this
alternative. The present worth cost of this alternative is
$1,194,000 to $1,606,755.
GROUND WATER TREATMENT AND FUEL OIL RECOVERY
Alternative 1—Fuel Oil Recovery and Ground Water Treatment:
Capital Cost: -0-
Annual O&M Costs: $120,000
Present Worth Costs: $1,131,120
This remedial alternative is currently being implemented. This
alternative involves on-site pumping of ground water contaminated
with fuel oil in the vicinity of the maintenance building using
three extraction wells, fuel oil recovery, ground water treatment
using activated carbon, and discharge of the treated ground water
on-site into the ground through an infiltration gallery. The
recovered fuel oil is collected and disposed off-site in an
approved RCRA disposal facility. Spent carbon would also be
disposed off-site in an approved facility as required under TSCA
and RCRA.
Ground water is contaminated with elevated levels of benzene,
toluene, ethylbenzene, and xylene (BTEX) from the fuel oil. The
MCL for benzene is 5 ug/1. Concentrations of benzene exceed the
MCL under the Safe Drinking Water Act, 42 U.S.C. SS 300(f)-300(j)
and 40 C.F.R. S 141.61. Ground water remediation will comply
with the Pennsylvania ARAR for ground water for hazardous
substances under PA Code SS 264.90-264.100 which requires that
all ground water must be remediated to background quality. To
the extent the EPA determines that background levels are less
stringent than MCLs or that it is not technically practicable to
remediate to background, then the remediation level will comply
with the MCL for benzene promulgated under the Federal Safe
Drinking Water Act, 42 U.S.C. 300f-300j, and 40 C.F.R. 141.61.
Periodic on-site and off-site ground water monitoring would be
provided over the life of this project to determine the
effectiveness of the remedial effort. Because this action is
currently ongoing, a No Action alternative will not be evaluated.
Chemical-specific ARARs include the Pennsylvania Hazardous Waste
Management Regulations, 25 PA Code SS 264.90-264.100,
specifically SS 264.97(i), (j) and 264.100(a)(9); the Safe
Drinking Water Act 42 U.S.C. SS 300f - 300j; and 40 C.F.R. Part
141, $ 141.61; and the Pennsylvania Safe Drinking Water Act, 35
P.S. SS 721.1-721.17, and 25 PA Code Chapter 109, specifically
SS 109.1-109.4, 109.201, and 109.202. Action-specific ARARs
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include RCRA Subtitle C, Hazardous Waste Management Requirements,
40 C.F.R. Parts 262, 263 and 264 which govern all waste material'
or product generated during remediation activities, other than
PCBs, which is determined to be a RCRA characteristic waste; and
the SDWA, 42 U.S.C. $ 300(d); and 40 C.F.R. Part 144.
Location-specific ARARs for this alternative include the Clean
Streams Law 35 P.S. $S 691.1 to 691.1001, and the National
Pollution Discharge Elimination System regulations, 25 PA Code
92, and the Water Quality Standards, 25 PA Code 93.
RAIL YARD BUILDINGS AND STRUCTURES
Alternative 1—No Aetiop
Capital Cost: -0-
Annual O&M Costs: $247,200
Present Worth Costs: $471,905
Implementation Time frame: None
No action would be taken to decontaminate or otherwise address
areas inside the car shop buildings contaminated with PCBs. The
1987 worker protection stipulation program would continue to be
implemented. There are no chemical, location or action-specific
ARARs for this alternative.
Alternative 2—Containment or Encapsulation
Capital Cost: $280,000
Annual O&M Costs: $10,000
Present Worth Costs: $846,165
Implementation Time frame: 12 months
Epoxy resin would be applied to approximately 35,000 square feet
of surface area in the car shop buildings with PCS concentrations
in excess of 10 ug/100 cm2. Approximately 30,000 square feet of
this area involves the concrete pits. This alternative would not
generate any contaminated wastewater or solid waste for disposal.
Proper personnel protective equipment and ventilation would be
required during application of the epoxy resin. The worker
protection stipulation program described under Alternative 1
would continue to be implemented. Action-specific ARARs include
the TSCA Disposal Requirements, 40 C.F.R. $, 76l.60(a)(2)(iii).
There are no chemical or location-specific ARARs for this Site.
Alternative 3—Decontamination
Capital Cost: $260,000
Annual O&M Costs: -0-
Present Worth Costs: $731,905
Implementation Time frame: 12 months
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This alternative would involve decontamination of approximately
35,000 square feet of high contact surfaces in the car shop
buildings having PCB concentrations in excess of 10 ug/ioo cm2.
High contact surfaces are defined as all wall surfaces up to
eight feet in height above the main floor of the building and all
surfaces within the repair pits. Depending on the type of
surface, decontamination would be accomplished by wiping with a
solvent, applying a chemical foam, shot blasting, or similar
methods. Both the liquid application methods and more
destructive blasting technology would generate waste material for
disposal, and the more destructive surface removal techniques
would generate large quantities of dust and debris for disposal.
Any blasting activity must comport with the Pennsylvania Air
Pollution Control Act, 25 PA Code Chapts. 123, 127; and with the
TSCA Disposal Requirements, 40 C.F.R. § 761.60. which are action-
specific ARARs for this alternative. There are no location or
chemical-specific ARARs for this alternative.
Proper personnel protective equipment would be required during
decontamination. The worker protectioh stipulation program
described under Alternative 1 would continue to be implemented.
Alternative 4—-Decontamination and Demolition
Capital Cost: $1,000,000
Annual O&M Costs: -0-
Present Worth Costs: $1,471,905
Implementation Time frame: 18 months
The building would be decontaminated as described in alternative
3 and demolished. The building materials would either be
disposed at an acceptable permitted facility or recycled. All
materials with PCBs in excess of 50 ppm would be separated from
the rest of the materials and either treated on-site in or
disposed off-site in a TSCA landfill. Any blasting or demolition
activity must comport with the Pennsylvania Air Pollution Control
Act, 25 PA Code Chapts. $$ 123.1, 123.2, 123.41, 127.1, 127.12
and 127.14 which are action-specific ARARs for this remedy.
Building demolition could not begin until after closure of the
rail yard. The present worth cost is estimated at $1,000,000 .
based on disposal of debris material as a non-PCB waste. If the
building were not decontaminated or the debris waste were
otherwise determined to be PCB waste, the present worth cost of
this alternative would be $8,834,750.
STREAM SEDIMENTS
Alternative 1—No Action
Capital Cost: -0-
Annual O&M Costs: $4,200
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Present Worth Costs: $39,600
Implementation Time frame: None
Under this alternative, no action would be taken to remediate
contaminated sediments located in the streams and tributaries
within the study area. A long-term environmental monitoring
program would be implemented to assess the effectiveness of this
alternative. This alternative would not comply with the Clean
Streams Law, 35 P.S. §§ 691.1 to 691.1001, the Water Quality
Standards, 25 PA Code Chapt. 92, and the National Pollution
Discharge Regulations, 25 PA Code Chapt 93. There are no
location or action-specific ARARs for this alternative.
Alternative 2— Containment
Capital Cost: $800,300
Annual O&M Costs: $5,430
Present Worth Costs: $851,500
Implementation Time frame: 2 months
Under this alternative, approximately 670 feet of stream
sediments containing PCB concentrations greater than 10 ppm would
be covered with a geotextile liner and rip rap to prevent erosion
and direct contact. Streams would be diverted temporarily during
implementation of this alternative. Temporary access roads would
also be required which would have an ecological impact on the
area. A long-term environmental monitoring program would be
implemented to assess the effectiveness of this alternative. The
Pennsylvania 0am Safety and Encroachments Act of 1978, P.L. 1375,
as amended. 32 P.S. §§ 693.1 et seq. and the Pennsylvania Dam
Safety and Waterway Management Regulations, 25 PA Code Si 105.1
g£ sjgg. apply to stream relocation and/or encroachments and to
wetland protection and are location-specific ARARS for this
alternative, other location-specific ARARs include 25 PA Code
§ 269(b)(l) and (2) which describe requirements for building a
facility within a protected river corridor.
Alternative 3~Exeavatien and T^rea^pent of Sediments with PCB
Concentration* Exeeedi.no 10 ppm and 1 ppm f Phased Approach!
Capital Cost: $860,810 to $881,060
Annual OUf Costs: $4,200
Present Worth Costs: $900,400 to $920,650
Implementation Time frame: 2 months
This alternative requires that contaminated sediments along
Valley Creek and Little Valley Creek and its tributaries be
excavated and returned to the rail yard. In addition, the
sediment inside the fence on Hollow Road would be excavated and
treated along with rail yard soils. A phased approach would be
implemented under this alternative. The first phase would
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involve excavation of 670 feet of stream sediments (63 cubic
yards) with PCB concentrations exceeding 10 ppa. Following
excavation, an environmental monitoring program would be
implemented to assess the impact of remediation on the levels of
PCBs in sediment, including Little Valley Creek and Valley Creek.
If PCB.levels do not decrease sufficiently to adequately protect
human health and the environment, then additional excavation of
approximately 6,800 feet .of stream sediments (720 cubic yards)
with PCB concentrations exceeding 1 ppm will be implemented. EPA
is proposing this alternative as a phased approach to first
evaluate the benefits of the initial stream excavation before
proceeding with more extensive remediation.
The Pennsylvania Clean Streams Law, 35 P.S. §§ 691.1 to 691.1001;
the Water Quality Standards, 25 PA Code Chapt. 93, and the
National Pollution Discharge Elimination System regulations, 25
PA Code Chapter 92; the Pennsylvania Dam Safety and Encroachments
Act of 1978, P.L. 1375, as amended. 32 P.S. §§ 693.1 ££ sea.; and
the Pennsylvania Dam Safety and waterway Management Regulation,
25 PA Code §S 105.1 s£ figg.; apply to'stream relocation and/or
encroachments, to wetland protection, and to discharges to
surface water, and are location-specific ARARs for this
alternative. The Endangered Species Act of 1973, 16 U.S.C.
§ 1651 ££ fififl., may be applicable if a determination is made that
endangered species are present or will be affected by the
remedial alternative. There are no chemical-specific or
action-specific ARARs for this alternative.
Alternative 4—Excavation and Treatment of Sediments with PCB
Concentrations Exceeding 1 ppm
Capital Cost: $5,701,720 to $5,909,220
Annual O&M Costs: -0-
Present Worth Co«t»: $5,701,720 to $5,909,220
Implementation Time frame: 10 months
This alternative requires that appproximately 7500 feet (785
cubic yards) of stream sediments along Valley Creek and Little
Valley Creek and its tributaries with PCB concentrations
exceeding 1 ppa be excavated and returned to the rail yard for
treatment. Sediment inside the fence on Hollow Road would be
excavated and treated along with rail yard soils. Initially,
stream areas exceeding 10 ppa would be excavated and natural
deposition areas would be excavated on a regular basis over a
period of five years. Streaa sediment monitoring will be
conducted periodically to evaluate the effectiveness of the
excavation program in achieving the 1 ppa cleanup standard.
After a period of five years, the need for additional stream
excavation in order to meet the 1 ppm cleanup standard will be
evaluated. Implementation of this alternative may require
installation of up to 12,000 feet of access roads based on
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estimates in the FS report. During implementation of the remedy,
destruction and loss of natural habitat along the stream
corridor (s) would need to be considered and minimized where
possible, using less destructive excavation methods such as
vacuum dredging of sediments. A restoration program will also be
required following remediation. See the discussion of ARARs in
Alternative 3 above for a list of those Federal and State
regulations that are ARARs for this alternative.
IX. SUMMARY OF COMPARATIVE ANALYSIS OP ALTERNATIVES
The remedial action alternatives described above were
evaluated using nine evaluation criteria. The resulting
strengths and weaknesses of the alternatives were then weighed to
identify the alternative providing the best balance among the
nine criteria. These criteria are:
Threshold Criteria
• Overall protection of human health and the environment;
• Compliance with applicable or relevant and appropriate
requirements ;
Primary Balancing Criteria.
• Reduction of toxicity, mobility, or volume;
• Implementability;
• Short-term effectiveness;
• Long-term effectiveness;
• Cost;
Modifying Criteria
• community acceptance;
• State acceptance;
rotection of Human Health and the
A primary requirement of CERCLA is that the selected remedial
action be protective of human health and the environment. A
remedy is protective if it eliminates, reduces, or controls
current and potential risks through each exposure pathway to
acceptable levels through treatment, engineering controls, or
institutional controls.
Based on the baseline risk assessment conducted by EPA, the
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greatest human health risk from exposure to PCBs is dermal
contact and incidental ingestion of PCBs. In order to meet
remedial objectives, the risk associated with exposure to PCB
contaminated soil must fall within the acceptable risk range of
10~4 to 10"6 for carcinogens, with 10"6 risk considered a point of
departure.
EPA has determined that an environmental risk exists requiring
remediation of PCB-contaminated stream sediments. This is based
on the presence of elevated levels of PCBs in sediments and
aquatic organisms, the known potential for food chain exposure
and bioaccumulation of PCBs, and the weight of evidence
indicating PCB toxicity at levels that exceed the baseline
levels for the Paoli study area.
All of the technologies that utilize excavation and treatment of
contaminated soils and sediments provide protection of human
health and the environment by removing PCB-contaminated soils and
sediments that exceed the risk-based cleanup standard and
solidifying them. The selected alternatives for rail yard soil
and residential soil reduce the incremental cancer risk to
approximately 10~5 after treatment.
Rail Yard Soils
Alternative 1 (No Action) and Alternative 2 (Institutional
Controls) are not protective since they would allow soil to
remain at concentrations exceeding risk-based cleanup standards.
Alternative 3 (Containment of Contaminated Soils ) would provide
less than adequate protection since no treatment would be used to
immobilize the contaminants from migrating off-site.
Alternative 4 (Excavation and treatment of soils with PCB
concentrations greater than 500 ppm) is not protective since a
major portion of the contaminated soil which exceeds a 10~4 risk
range is not treated or contained.
Alternative 5 (Excavation and treatment of soils with PCB
concentrations greater than 25 ppm) provide adequate protection
of human health because it reduces the incremental cancer risk to
approximately 10~5 after treatment. EPA believes it is not
technically practicable to reduce risks to the 10~6 or lower risk
range based on the quantity of soil to be treated, the practical
limits of detection of PCB in soil, and institutional controls
requiring that the future use of the rail yard be limited to non-
residential use. Alternatives 3 and 6 would provide less than
adequate protection of human health and the environment since
containment rather than treatment is used.
Alternative 6 (Excavation and treatment using stabilization/
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solidification of soil with PCS concentration exceeding 500 ppn
and containment of soil with PCB concentrations between 25 and
500 ppm) would provide limited protection to on-site workers .and
would allow for the future migration of PCB contamination into
neighboring residential areas and into ecologically sensitive
streams.
Alternative 7 (Excavation and off-site disposal of soils and
sediments) would be protective at the Paoli Rail Yard Site but
would result in transferring risks from one location to a
subsequent location where the wastes are disposed.
Residential and other Soils
Alternative 1 (No Action) would not be protective since it would
allow soil to remain in residential areas at concentrations up to
50 ppm equivalent to a risk that exceeds the 10'4 risk range.
Alternative 2 (Excavation and treatment of residential soils)
would provide an adequate level of PCB protection (2 ppm average
per property) to residents, especially children.
Ground Water Treatment and Fuel Oil Recovery
The alternative for fuel oil recovery and ground water treatment
is protective and meets the acceptable risk range for benzene (a
carcinogen) by attaining the Federal HCL concentration. This
alternative provides the best level of long-term protection of
human health and the environment.
Rail Yard Buildings and Structures
Alternative 1 (No Action) would require that the 1987 worker
protection program stipulation continue to be implemented and
would adequately protect workers potentially exposed in the car
shop and rail yard. This alternative would not be protective to
any future workers, or to any future yard or building inhabitants
or workers.
Alternative 2 (Containment or Encapsulation) would result in a
short-term remedy adequate to protect health of workers and
nearby residents but provide no assurance that future use
scenarios could maintain this level of protection. In addition,
future demolition of the buildings could result in exposures to
workers and to local residents, and would result in higher
disposal costs.
Alternative 3 (Decontamination) for rail yard buildings .and
structures requires workers to wear personnel protection gear and
follow hygiene protocols during use of the building by SEPTA
employees. Decontamination of the building after the rail yard
maintenance activities cease will ainiaize any future risk by
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eliminating the most highly contaminated surfaces in the interior
of the car shop building.
Alternative 4 (Decontamination and Demolition) would require that
all rail maintenance buildings be decontaminated prior to
demolition and disposal, and would likely require that demolition
debris be disposed off -site, resulting in increased risk during
demolition and off -site transport.
Stream Sediments
Alternative 1 (No Action) would not protect humans or plant and
animal lifeforms indigenous to the streams and the associated
environment .
Alternative 2 (Containment) would contain the migration of
contaminants further downstream in the various connecting
streams. This alternative would not reduce the volume of
contaminants already in the stream and associated runoff areas.
Since it is known that significant concentrations of PCBs exist
in the stream and biomass, this alternative would not provide
adequate protection to sensitive species nor would it reduce the
existing accumulation of PCBs.
Alternative 3 (Phased Approach) would be less protective than .
alternative 4 since stream sediment concentrations less than 10
ppm would not be excavated unless additional environmental
monitoring demonstrated that further stream excavation is
warranted, and would not provide for periodic continued
excavation over a five year period with stream monitoring as
described under Alternative 4. Although this approach would
initially minimize any impacts to the stream by excavation,
Alternative 3 would not ensure that the cleanup standard of l ppm
would be achieved in a reasonable period of time.
Alternative 4 (Excavation and Treatment of Sediments with PCB
concentrations Exceeding 1 ppm) would provide a greater level of
protection than Alternative 3 and could be achieved with minimal
environmental damage as described in the ROD. EPA believes that
a cleanup standard of 1 ppm will provide adequate protection of
the environment and that lover cleanup standards could not be
achieved without significant deleterious effects to the local
environment.
I lanes iflth Applicable or Relevant and Appropriate
Compliance with ARARs addresses whether a remedy will meet all
Federal and State environmental laws and/or provide the .basis for
a waiver from any of these laws. The selected remedy will meet
all ARARs as described under Statutory Determinations except for
the TSCA chemical waste landfill requirements, 40 C.F.R. S
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761.75, which are waived pursuant to the waiver authority
contained under CERCLA S 121(d)(4) as discussed under Statutory
Determinations. TSCA requirements are potential ARARs for each
remedy involving remediation and landfilling of PCB contaminated
wastes.
PCBs are addressed under RCRA in 40 CFR Part 268 which describes
the prohibitions on land'disposal of various hazardous wastes.
PCBs alone are not a RCRA hazardous waste. RCRA-listed waste was
not disposed at the rail yard and the contaminated PCB soil is
not a RCRA-characteristic waste. RCRA prohibitions on land
disposal of hazardous waste and RCRA closure requirements are not
considered ARARs for this Site. Any waste material or product
generated during remediation activities which is determined to be
a RCRA characteristic waste will be disposed in accordance with
RCRA Subtitle C, Hazardous Waste Management Requirements.
Ground water remediation will comply with the Pennsylvania ARAR
for ground water for hazardous substances under PA Code
§§ 264.90-264.100 which requires that all ground water must be
remediated to background quality. To the extent the EPA
determines that background levels are less stringent than MCLs or
that it is not technically practicable to remediate to
background, then the remediation level will comply with the MCL
for benzene (5ug/l) promulgated under the Federal Safe Drinking
Water Act ("SDWA"), 42 U.S.C. 300f-300j, and 40 C.F.R. 141.61.
g. Reduction of Togi.ei.tv. Mobility* or Volima Throwrti Treatment
Rail Yard Soils
This evaluation criteria addresses the degree to which a
technology or remedial alternative reduces toxicity, mobility, or
volume of hazardous substances. The Superfund program, as
required by the NCP, uses as a guideline for effective treatment
the range of 90 to 99 percent reduction in the concentration or
mobility of contaminants of concern.
Alternative l (Mo Action), Alternative 2 (institutional
controls), and Alternative 7 (excavation and off-site disposal)
do not provide for treatment to reduce toxicity, mobility, or
volume of contaminated soil through treatment.
Alternative 3 (containment) provides no reduction of toxicity or
volume through treatment but does reduce the mobility of the
waste through containment.
Alternatives 4 and 5 employ treatment using either the -
solidification/stabilization process, the KPEG process, or
incineration. Alternative 5A, the preferred alternative for
excavation and treatment of soils and sediments, will limit the
mobility of PCBs since the physical and chemical characteristics
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of the waste will be altered through treatment, but will not
reduce toxicity or volume. The mobility of the waste will be
limited by immobilization using the stabilization/solidification
process, but will not achieve a toxicity reduction of 90 to 99
percent based on the PCB concentration in the untreated soil and
the solidified soil. None of the treatment alternatives
evaluated will reduce the volume of waste. Treatment
alternatives using incineration or the KPEG process will reduce
toxicity by destroying PCBS to varying degrees. The soil treated
by incineration would be expected to exhibit toxic leaching
characteristics for certain metals, thereby increasing the
toxicity and mobility.
Alternative 6 (treatment and containment) provides less treatment
since only wastes above 500 ppm PCBs are treated.
Residential and other Soils
Alternative 1 (No Action) requires no further excavation and
treatment of residential soils and provides no reduction of
toxicity, mobility, or volume through treatment.
Alternative 2 will reduce the toxicity, mobility, and volume of
contaminated soil in the residential area through excavation and
treatment of the soil at the rail yard.
Ground Water Treatment and Fuel Oil Recovery
Ground water treatment would reduce the toxicity and mobility of
contaminants in ground water by treating benzene in ground water
and by recovering fuel oil.
Rail Yard Buildings and Structures
Alternative 1 (No Action) would not reduce the toxicity,
mobility, or volume through treatment.
Alternative 2 (containment or encapsulation) would reduce the
mobility of the waste on a short-term basis by applying an epoxy
resin to the car shop surface, but would not reduce the toxicity
or volume of contaminated building surfaces.
Both Alternative 3 (decontamination) and Alternative 4
(decontamination and demolition) would reduce the toxicity, .
mobility, and volume of contaminated surfaces within the car shop
building using a destruction decontamination technology such as a
liquid solvent, chemical foam, or shot blasting. Alternative 4
would result in the complete removal of decontaminated building
material from the rail yard but would not significantly increase
the amount of building material decontaminated when compared with
Alternative 3.
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fit: re am Sediments
Alternative 1 (No Action) would not reduce the toxicity,
mobility, or volume through treatment.
Alternative 2 (containment) would reduce the mobility of
contaminated sediments caused by stream erosion but would not
reduce the toxicity or volume of contaminants through treatment.
Alternatives 3 and 4 employing treatment would reduce the.
toxicity, mobility, and volume by excavating contaminated stream
sediments. Alternative 4 would ultimately result in greater
reduction of contaminated sediments since a 1 ppm cleanup
standard would be implemented versus a 10 ppa cleanup standard
under Alternative 3.
D. Short-Tera Effectiveness
Short-term effectiveness involves the period of time needed to
achieve protection and any adverse impacts of human health and
the environment that may be posed during the construction and
implementation period until cleanup standards are achieved.
Rail Yard Soil
Alternative 1 (No Action) and Alternative 2 (institutional
controls) could be implemented immediately and would not have any
adverse impacts.
Alternative 3 (containment) would require that a large amount of
clean soil be brought onto the rail yard and would likely result
in increased truck traffic and generation of dust during
construction of the containment cover. Dust suppression measures
and air monitoring would be required. This work could be
completed in a short time frame of approximately 6 months.
Alternatives 4, 5, and 6 would involve excavation and treatment
of contaminated coil. Some participate emissions may occur
during implementation. Dust suppression control measures during
excavation of rail yard soils and residential soils and air
monitoring would be required. During construction there would be
noise and truck traffic that may temporarily affect local
residents. Alternatives 3 and 6 which involve containment would
be anticipated to have fewer short-term adverse impacts than
Alternatives 4 and 5 which require treatment of contaminated
soils.
Alternative 7 would require excavation and off-site disposal
involving transportation of contaminated material and would have
more potential for short-term adverse impacts than Alternatives
2, 3, 4, 5, and 6 since a larger population would be exposed to
contaminated material. Alternative 7 would require approximately
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two years to implement.
Because the Paoli rail yard is currently an active rail yard
facility and is not expected to cease operation until June 1994,
remediation of rail yard soils can not begin until the rail yard
closes. Implemention of Alternative 5 will require approximately
2 years to complete. Alternatives 3, 4, and 6 will require 6 to
12 months to complete since less soil will be excavated and
treated compared to alternative 5.
Residential and other Soil
Alternative 1 (No Action) could be implemented immediately with
no adverse impact.
Alternative 2 requiring excavation of residential soil would be
expected to inconvenience residents. During construction there
would be noise and truck traffic that may temporarily affect
local residents. Dust suppression control measures during
excavation and air monitoring would be* required. Residential
soil excavation can be implemented within approximately six
months after work begins and can be completed during the time
that the rail yard is still operating.
Ground Water Treatment and Fuel Oil Recovery
The fuel oil recovery and ground water treatment program is now
ongoing and is expected to be a long-term remedial action.
Rail Yard Buildings and Structures
Alternative l could be implemented immediately with no short-term
health impacts.
Alternatives 2, 3, and 4 would generate dust during the process
and construction workers could be exposed to PCBs through direct
contact with dust through inhalation or incidental ingestion.
Suitable personnel protection equipment would be required along
with dust suppressant controls. Alternatives 2, 3 and 4 would
not be implemented until after remediation of rail yard soils was
completed to prevent further contamination of the building.
Alternatives 2 and 3 would each require approximately 12 months
to complete; Alternative 4 would require 18 months with the
additional time needed for building demolition.
Stream Sediments
Alternative 1 (No Action) could be implemented immediately with
no adverse impact.
Alternative 2 (containment) would require that streams be
temporarily diverted and access roads be constructed during
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implementation of the alternative. This would have an ecological
impact on the area and result in suspension of stream sediments.
This alternative would require two months to implement.
Alternatives 3 and 4 would result in disturbance of the stream
areas.excavated and surrounding resource areas due to suspension
of sediment and construction of access roads. Such impacts may
include the destruction of natural vegetation and trees, and the
loss of plant and aquatic organisms. During implementation,
steps will be taken to minimize habitat damage and reduce the
amount of road construction required by using less destructive
methods of stream excavation such as vacuum dredging to the
maximum extent practicable. Any wetland areas impacted will be
restored. Alternative 4 selected in the ROD would be implemented
over a 5 year period while remediation of residential soils, rail
yard soils, and buildings and structures is completed.
E. Long-Tarn Effectiveness and Permanence
Long-term effectiveness and permanence* refers to the ability of a
remedy to maintain reliable protection of human health and the
environment over time once cleanup standards have been met.
Rail Yard Soils
Alternatives l and 2 which do not provide treatment, do not
provide reliable protection of human health and the environment
over time.
Alternatives 4, 5, 6, and 7 involving excavation and treatment of
rail yard soils will be effective and permanent solutions to the
risks currently posed by PCB-contaminanted soil. Treatment using
stabilization/solidification in combination with long-term
management controls and placement of the solidified material in a
containment cell will permanently reduce risk through direct
contact and exposure and prevent PCB transport through leaching,
erosion, and runoff. The preferred alternative which immobilizes
PCBs through solidification will provide less long term
permanence than alternatives such as incineration, but provides a
much greater degree of long-term effectiveness and permanence
than Alternative 3, containment.
Residential and other Soils
Alternative l does not provide reliable protection of human
health and the environment over time.
Alternative 2 (excavation of PCB contaminated soil 2 ppm or
greater) will provide a highly effective and permanent solution
to the risk in the residential neighborhood currently posed by
PCB-contaminated soil.
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Ground Water Treatment and Fuel oil Recovery
The preferred alternative for ground water remediation will
prevent any migration of fuel oil and PCBs from the vicinity of
the rail yard and will require long-term ground water monitoring.
Rail Yard Buildings and Structures
Alternatives 1 (No Action) and 2 (containment) provide less long-
term protection than Alternatives 3 and 4. Decontamination of
building surfaces is a highly effective method of treatment for
PCS removal. Alternative 4 would effectively remove all building
surfaces following decontamination.
Stream Sediments
Alternative 1 would provide no long-term protection and
Alternative 2 (containment) would be less effective than stream
excavation due to the possibility of long-term erosion of the
contained area and increased maintenance.
Alternatives 3 and 4 requiring stream excavation would be highly
effective over the long-term in eliminating the environmental
impact from PCB contamination.
F. Implementability
Implementability is the technical and administrative feasibility
of a remedy, including the availability of goods and services
needed to implement the chosen solution.
Rail Yard Soil
After the rail yard ceases operation and railroad tracks are
removed, soil excavation and treatment will be relatively easy to
implement. Stabilization/solidification is a demonstrated
technology and treatability studies using soil from the Site have
been conducted to evaluate the effectiveness of the technology.
Additional treatability studies will be required prior to final
design. Use of a mobile incinerator is less common than use of a
fixed place incinerator. A trial burn would be required to
demonstrate this technology and the treated soil would be
expected to exhibit toxic leaching characteristics, requiring
possible additional treatment to render the treated soil
non-toxic and reduce mobility of the soil. The KPEG process has
been demonstrated on a laboratory scale but has limited field
testing. Treatability tests during the FS on soils from the Paoli
rail yard indicated that the high cinder and ash content would
cause potential operational and maintenance problems with solids
handling. Off-site disposal of contaminated soils would be
dependent on the availability of a TSCA-permitted landfill which
are not located along the east coast. Transportation would be by
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rail car if possible to minimize truck traffic and use of open
roads .
Residential and other
Alternative 1 would require no excavation. Alternative 2 could
be implemented using excavation procedures similar to the
previous soil removal program conducted in 1988-1989 using
excavation equipment and hand excavation for soil removal.
Erosion control measures would be used, access would be
restricted to excavation areas, and excavated areas would be
backfilled with clean soil and revegetated in consultation with
individual property owners. Site access to private properties
will be required.
Rail Yard Buildings and Structures
Decontamination methods proposed under Alternatives 3 and 4 for
the car shop surfaces have been demonstrated in the TSCA program.
*
Demolition of the car shop buildings and structures under
Alternative 4 would not be necessary for remediation of the rail
yard soils and the building can be satisfactorily decontaminated
without demolition. Demolition would result in increasing health
impacts on construction workers and the surrounding community and
may increase the cost of the remedy by an additional $7 million
if the demolished building material must be disposed off-site at
a TSCA landfill.
Ground Water Treatment and Fuel Oil Recovery
The ability to implement the fuel oil recovery system has already
been demonstrated.
Stream Sediments
Alternatives 2, 3, and 4 could be implemented but would require a
certain amount of construction of access roads which may be
difficult in some areas because of the steep terrain.
Alternative 4 proposes to minimize the construction of access
roads and the amount of truck traffic required by use of vacuum
dredging and additional stream monitoring and sediment transport
studies to measure the effectiveness of the remediation.
Q. cost
The present worth cost of each alternative, along with the
capital cost and annual operation and maintenance cost, -is
described under each alternative under Section VIZI, Description
of Alternatives.
The estimated cost of all the selected alternatives is
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approximately $28,268,000. This figure represents the "present
worth value" of all future cost activities associated with the
selected alternative. This estimate is used for cost comparison
purposesi Treatment of additional quantities of soils and
sediments other than what has been estimated in the ROD and FS
will also change the cost of remediation proportionately, other
treatment alternatives using either the KPEG process or
incineration have higher fixed costs, while containment options
have lower fixed costs.
H, State Acceptance
The Commonwealth of Pennsylvania concurs with the selected
remedy.
I.Community Acceptance
Community acceptance is assessed in the attached Responsiveness
Summary. Several members of the local community requested that
the car shop building be demolished. Other commentors requested
that more stringent cleanup standards be set. EPA received a
number of comments requesting that the environmental impact of
the stream remediation be further considered when selecting the
cleanup alternative for stream sediments. The PRPs did not concur
with the remedy selection.
X. 8ELBCTBP REMEDY: DESCRIPTION AMP PERFORMANCE STANDARDS)
FOR EACH COMPONENT Of THE REMEDY
EPA has selected the following remedies for the Paoli Rail Yard
Site:
Rail Yard Soilsi The selected alternative is Alternative 5A.
This alternative requires excavation and on-site treatment of
contaminated soils using stabilization/solidification for soils
with PCB concentrations exceeding 25 ppm, and deed restrictions.
After treatment, the solidified material would be placed back
on-site in a containment cell.
Ground water Treatment and Fuel oil Recovery* The selected
alternative is Alternative l. This alternative requires
continued implementation of the fuel oil recovery and ground
water treatment program and ground water monitoring.
Rail Yard Buildings and Structures: The selected alternative is
Alternative 3, decontamination of surfaces having PCB
concentrations in excess of 10 ug/100 cm2.
Residential and Other Soilss The selected alternative is
Alternative 2, excavation of residential soils to achieve an
average PCB concentration of 2 ppm per individual property.
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Stream Sediments: The selected alternative is Alternative 4,
excavation of stream sediments exceeding l ppm.
The performance standard(s) for each selected alternative will be
described below.
Performance Standards
Rail Yard Soil
A. Performance Standards
The selected remedial action shall require excavation and on-site
treatment of rail yard soils with PCS concentrations of 25 mg/kg
or greater using a stabilization/solidification process. This
would require excavation and treatment of approximately 28,000
cubic yards of contaminated soil located over approximately 15
acres of the rail yard property, primarily in the vicinity of the
existing rail tracks. This remedial auction shall include
treatment of approximately 3000 cubic yards of soil from the
previous residential soil removal program now located on the rail
yard property in a lined containment cell.
In order to evaluate the effectiveness of the stabilization and
solidification process, the following physical and chemical tests
of treated solidified soil shall be established as Performance
Standards. Performance standards shall be demonstrated in the
laboratory and in field testing during construction.
-The Toxicity Characteristic Leaching Procedure (TCLP) test for
PCBs shall be 4 ppb or less.
-The 28-day unconfined compressive strength shall be greater than
100 psi (ASTM Method 02166 or equivalent).
-The triaxial permeability shall be less than 1 x 10~7 cm/sec
(USAGE Method 1110-2-1906 or equivalent).
All contaminated soil which has been treated using the
stabilization/solidification process shall be placed on rail yard
property in a dedicated containment cell (or cells). The
location of the cell (or cells) shall be determined during
remedial design. The containment cell(s) shall be constructed to
include a monitoring system capable of detecting leakage from the
cell(s). Ground water monitoring for PCBs, metals, volatile
organic compounds, and semi-volatile organic compounds shall be
conducted on a quarterly basis for the first two years of
operation and semi-annually thereafter with approval of. EPA in
consultation with Pennsylvania DER. Routine maintenance and
inspection of the cell(s) shall b« performed.
The containment cell(s) shall be designed with a final
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impermeable cap designed to: (1) provide a hydraulic barrier
with a hydraulic conductivity of 10"7 cm/sec or less; (2) provide
long-term minimization of migration of liquid through the
containment cell; (3) minimize erosion or abrasion of the cover,
and (4) prevent freezing and thawing effects of the solidified
material (This impermeable cap is not a RCRA cap and there are no
RCRA ARARs that are applicable, relevant or appropriate).
Excavated areas of contaminated soil shall be backfilled with
clean soil, graded to contour, and revegetated. Routine
maintenance and inspection of the excavated area shall be
performed.
Air monitoring shall be required during excavation of rail yard
and residential soils and operation of the stabilization and
solidification process to determine if there are emissions of
PCBs adsorbed to particulates or if PCBs or other organics are
otherwise volatilized. Dust suppression measures such as
application of water or foam sprays shell be required, and
additional mitigative measures in addition to dust suppression
measures shall be taken if necessary to meet State and Federal
air pollution requirements.
Because the remediation is scheduled to be conducted in
conjunction with cessation of rail yard operation, all rail track
and railroad ties in the vicinity of the excavated soil, along
with the railroad tie pile in the vicinity of the turnaround
track, shall be removed/ decontaminated, and either reused,
transferred to a scrap metal dealer, or otherwise disposed
off-site. Other rail yard debris would be disposed in a similar
manner. All off-site disposal shall be done in compliance with
Federal and State ARARs.
Because the selected remedy will result in contaminants remaining
on-site, 5-year sit* reviews under Section 121(c) of CERCLA will
be required to monitor the effectiveness of the remedy.
B. Erosion and Sedimentation Controls
A storm water collection system consisting of three catch basins,
diversion controls, and filter fabric has been constructed to
manage and control storm water runoff and erosion from the rail
yard. The performance standard for this system shall be that it:
(1) effectively collect and control at least the water volume
resulting from a 24-hour, 25-year storm and prevent or
effectively minimize erosion from the rail yard property, both
prior to, during, and after construction; and (2) be inspected
and maintained on a regular basis (at least semi-annually).
In order to maintain the integrity and effectiveness of this
system, an erosion and sedimentation control plan shall b«
submitted as part of the remedial design to evaluate the
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effectiveness of the existing system and make recommendations for
any changes in the system based on construction activities and
closure of the rail yard. This plan shall evaluate the
effectiveness of the present Site erosion and sedimentation
controls to include sampling of surface runoff to provide a base
line from which future erosion and sedimentation control measures
shall be determined.
C. Deed Restrictions
As soon as practicable, restrictions shall be placed in the deed
to the rail yard to prohibit: (l) use of the property for
residential or agricultural purposes; and (2) the use of on-site
ground water for domestic purposes, including drinking water.
The continuing need for these restrictions will be re-evaluated
during the 5-year site reviews under Section 121(c) of CERCLA.
D. Additional Treatabilitv Studies
During the FS, treatability studies were conducted on the
solidified rail yard soil to evaluate the PCB leaching
characteristics and structural integrity of the solidified
material. Additional testing methods are available that provide
a variety of additional information on mobility and leaching
characteristics of PCBs depending on the specific test.
An expanded treatability study shall be conducted as soon as
practicable to further assess the stability and physical
characteristics of the stabilization/solidification process and
to demonstrate the predicted effectiveness of the
stabilization/solidification process. The recommended tests
shall include, but not be limited to, (1) the American Nuclear
Society Leach Test Method ANS-16.1 conducted for a 90-day period
(2) TCLP analysis on the intact solidified material (3)
additional leaching test(s) on solidified samples subjected to
test procedures to simulate long tent weathering such as
freeze-thaw, compression, etc., and (4) evaluation of
chemical/physical properties such as temperature and pH on the
solidification process.
E. Fuel Oil Soils
An estimated 14,000 cubic yards of subsurface soils contaminated
with PCBs and fuel oil at depths of 20 feet or more are located
in the vicinity of the car shop building. PCB concentrations
range froa 1 ppm to 500 ppm, with approximately 100 cubic yards
containing PCBs at concentrations greater than 500 ppm. This
area is now covered with an impermeable asphalt cover and will be
remediated by a ground water treatment and fuel oil recovery
system as described in the ROD.
EPA is not requiring that the subsurface fuel oil soils be
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excavated and treated. The asphalt cover shall remain intact and
the ground water treatment and fuel oil recovery system shall be
effectively operated to achieve ground water cleanup standards
required- in the ROD. If the pump and treat system is determined
to be ineffective in recovering fuel oil and remediating the
contaminated ground water plume, then EPA might determine that
the contaminated soil with PCS concentrations equal to or
exceeding 25 ppm shall be excavated. If such a decision is made,
EPA will amend the ROD or issue an Explanation of Significant
Differences in accordance with the National Contingency Plan.
Rail Yard Buildings and structures
Decontamination of approximately 35,000 square feet of rail yard
car shop buildings and structures shall be required following
completion of rail yard construction activities. The performance
standard shall require decontamination of high contact surface
areas that exceed a PCB concentration of 10 ug/100 cm2 based on a
standard wipe test sampling procedure. Depending on the type of
surface material, decontamination shall be accomplished by wiping
with a solvent, applying a chemical foam, shot blasting, or
equivalent methods. Proper personnel protective equipment shall
be required during decontamination. Any liquids, dust, or debris
generated during decontamination shall be collected for disposal.
Decontamination procedures shall be conducted in accordance with
the Federal and State regulations.
SEPTA has implemented a worker protection program in accordance
with a Stipulation filed July 13, 1987 between SEPTA and the
United States of America. The performance standard for this ROD
shall require that this Stipulation continue to be implemented.
Ground Water Treatment and Fuel Oil Recovery
Ground water in the vicinity of the car shop building is
contaminated with fuel oil and elevated levels of benzene,
toluene, ethylbenzene, and xylene (BTEX) from the fuel oil. The
preferred remedial alternative is currently being implemented.
This alternative shall require recovery of on-site ground water
in the vicinity of the car shop contaminated with fuel oil,
ground water treatment using filtration and activated carbon, and
discharge of the treated ground water on-site through a
subsurface infiltration gallery. The recovered fuel oil shall be
disposed off -site at an EPA approved disposal facility.
Standards for Ground Water
The ground water treatment system and fuel oil recovery system
shall continue to be operated throughout the area of fuel oil
contamination on a continuous basis to (l) remove fuel oil to the
maximum extent practicable, and (2) achieve the MCL for benzene
or the background concentration for benzene, whichever is more
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stringent. EPA shall determine the background concentration for
benzene based on data obtained using procedures for ground water
monitoring outlined in 25 PA Code $ 264.97. in the event that
benzene is not detected in samples taken for the establishment of
a background concentration, the detection limit for the method of
analysis utilized with respect to benzene shall constitute the
"background11 concentration of the contaminant.
The remediation goal to achieve a background concentration of
benzene is based on achieving the Pennsylvania ARAR under 25 PA
Code §S 264.90-264.100 which requires aquifer remediation of
contaminants of concern to background levels. The MCL for
benzene established under the Federal Safe Drinking Water Act
(the Federal ARAR) is 5 ug/1. The MCL for benzene is set forth
at 40 C.F.R. §141.61. The detection limit for benzene is 0.2
ug/1 based on method 601/602 found at 40 C.F.R. Part 136.
If EPA determines that implementation of the selected remedy
demonstrates that it will be technically impracticable to achieve
and maintain the performance standards' throughout the entire area
of ground water contamination, chemical-specific ARARs may be
waived for those portions of the aquifer for which EPA determines
that it is technically impracticable to achieve further
contaminant reduction.
Achieving the concentration ARAR for ground water shall mean that
ARAR levels for benzene have been attained throughout the area of
attainment and remain at the required levels for twelve
consecutive quarters. If it becomes apparent to EPA during
implementation or operation of the ground water extraction system
that contaminant levels have ceased to decline and are remaining
constant at levels higher than the Performance Standards over
some portion of the contaminated area, then EPA will determine
the need for additional response.
All extracted ground water shall be treated to levels which shall
permit subsurface discharge on-site in compliance with Federal
and State regulations as discussed in the groundwater
alternatives. Recovered fuel oil and spent carbon from the
ground water treatment system shall be disposed off-site in
accordance with Federal and State regulations.
EPA has evaluated the potential for PCBs leaching into ground
water at the PCS cleanup standard concentration in soil remaining
after completion of the remediation. The leaching potential of
PCBs at varying concentrations and using different cap designs
has been evaluated in the EPA "Guidance or Remedial Actions for
Super fund Sites with PCS Contamination," OSWER Directive No.
9355.4-01, August,. 1990. A transport model for PCBs was used at
Paoli since PCBs are the primary contaminant of concern. The
transport model predicts that for a PCB concentration of 20 ppm
in the soil, the maximum concentrations in the ground water will
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be 0.116 ug/1 (ppb) for an impermeable cap with permeability of
10~7 cm/sec (similar to Paoli design) occurring after 1645 years.
This analysis indicates there is no potential threat to ground
water especially in light of the high clay content of the native
soils.
B. Lona-Term Ground Water Monitoring
A long-term ground water monitoring program shall be implemented
to evaluate the effectiveness of the ground water pumping and
treatment system and fuel oil recovery system. Monitoring wells
installed in the area of fuel oil contamination shall be sampled
until such time as EPA determines that the Performance Standard
has been achieved to the extent technically practicable
throughout the entire area of contamination. Sampling shall be
conducted on a quarterly basis and shall include, as a minimum,
BTEX compounds, total petroleum hydrocarbons, and PCBs. The PCB
concentration in recovered fuel oil shall be sampled on a
semi-annual basis. If ground water monitoring indicates the
presence of PCBs for two consecutive quarters, EPA will consider
appropriate responses.
Sampling of residential wells was not included in the RI, as most
residences in the study area are supplied by public water having
a source outside of the study area. Private residences along
Hollow Road have been identified that continue to use wells for
water supply. As part of the long-term ground water monitoring
program, sampling of each well shall be conducted on an annual
basis and shall include, as a minimum, PCBs, volatile organic
componds, and semi-volatile organic compounds. If any ground
water monitoring event indicates the presence of contaminants
that exceed a final or proposed MCL, then the well shall be
resampled immediately, and EPA shall consider appropriate
responses.
Residential Soils
Cleanup standards for residential soil shall be accomplished by
excavating soil from individual private properties adjacent to
the rail yard in order to achieve an average PCB concentration of
2 ppm per individual property. The depth of excavation shall be
a minimum of 12 inches. Excavated soil will be returned to rail
yard property and treated using the stabilization and
solidification process. The entire area of excavation shall be
backfilled with clean soil, graded, revegetated, and restored to
its original condition.
During the conduct of the RI, composite and grab samples were
collected from individual properties to determine the extent of
contamination. Composite samples were primarily used to define
areas of contamination in residential yards.
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Where a composite property sample collected during the RI
indicates a PCB concentration of greater than 2 ppm, either (1)
the entire area sampled (i.e., entire front yard, flower garden,
play area, etc.) shall be excavated or (2) or a representative
number of discrete grab samples shall be collected to define
areas of excavation.
Discrete surface soil sampling shall be required to verify if the
cleanup standard of 2 ppm has been achieved. The cleanup
standard of 2 ppm shall be achieved if, after excavation and
backfilling, verification sampling using a representative number
of discrete grab samples from both excavated and non-disturbed
areas indicates that the average value of the samples is 2 ppm or
less. Surface soil samples shall be collected from approximately
the top 1 inch of soil.
o*1!! Sediments
The selected alternative shall require a cleanup standard of 1
ppm PCBs for stream sediments and stream banks along North Valley
Creek, Hollow creek, and Cedar Hollow Creek (all tributaries to
Little Valley Creek) and Little Valley and Valley Creeks.
Contaminated sediment shall be returned to the rail yard and
treated using the stabilization/solidification process.
The Commonwealth of Pennsylvania and Federal governmental
agencies believe that the concentration and location of PCB
contaminated stream sediments as identified in the RI/RA and FS
reports may change over time due to sediment transport and other
factors. Additional baseline stream corridor sampling for PCBs
shall be required prior to implementation of the remedy to better
define areas to be remediated. Historical hydrographs and
sediment transport studies shall be developed on an ongoing basis
to measure the effectiveness of the interim remediation.
Specific sampling locations shall be determined during remedial
design.
Limited excavation of stream sediments and stream banks shall
begin as soon as practicable following issuance of the ROD using
the following approach. Stream areas exceeding 10 ppm shall be
excavated as soon as practicable and natural deposition areas
shall be identified and excavated on a regular basis as a means
of implementing the remedy and achieving the 1 ppm cleanup
standard. The exact location of natural deposition areas and'
areas exceeding 10 ppm shall be determined during remedial
design. These areas of natural deposition shall be monitored
periodically for PCB levels and cleaned on a semi-annual basis or
more frequently based on the stream monitoring results, rainfall
events, and prediction of sediment deposition. The excavation
of stream areas and periodic removal of sediment from natural
deposition areas shall be designed to minimize environmental
damage and utilize, to the maximum extent practicable, excavation
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methods such as vacuum dredging or other alternative excavation
methods.
After a period of five years following start of construction and,
upon approval by EPA in consultation with the Commonwealth of
Pennsylvania, stream segments exceeding the 1 ppm cleanup
standard shall be considered for excavation. The determination
whether excavation shall be required will be based on a review of
PCB monitoring data, the expected environmental impact of
excavation, determination of the efficiency of the natural stream
deposition areas, and other site related factors such as sediment
transport of PCBs.
Implementation of the remedy may result in unavoidable impacts
and disturbance of the stream(s) and surrounding resource areas
due to stream sediment excavation and construction of access
roads. Such impacts may include the destruction of natural
vegetation and trees, and the loss of plant and aquatic
organisms. Impacts to the stream(s) and surrounding area shall
be mitigated as described below.
During implementation of the remedy, steps shall be taken to
minimize the destruction, loss, and degradation of natural
habitat and to minimize habitat alterations in the stream
channels and riparian zones. A restoration program will be
implemented upon completion of the remedial activities in areas
adversely impacted by the remedial action and ancillary
activities. In particular, a less destructive method of stream
excavation such as vacuum dredging shall be considered to the
maximum extent practicable. Any wetland areas impacted by
sediment removal and/or associated activities shall be restored
and/or enhanced, to the maximum extent practicable.
The restoration program shall be developed in detail during
remedial design of the selected remedy. This program shall
identify the factors which are key to a successful restoration
program. Factors shall include, but are not limited to,
replacing and regrading soils and vegetative re-establishment.
The restoration program shall include monitoring requirements to
determine the success of the restoration. Periodic maintenance
(i.e. planting) may also be necessary to ensure final
restoration.
The need for continuing stream sediment monitoring and additional
stream corridor restoration will be evaluated during the 5-year
site reviews under Section 121(c) of CERCLA to monitor the
effectiveness of the remedy.
XI. STATUTORY DETERMINATIONS
EPA's primary responsibility at Superfund sites is to select
remedial actions that are protective of human health and the
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environment. Section 121 of CERCLA also requires that the
selected remedial action comply with ARARs, be cost-effective,
and utilize permanent treatment technologies to the maximum
extent practicable. The following sections discuss how the
selected remedies meet these statutory requirements.
A. Protection of Hunan Health and Environment
Based on the baseline risk 'assessment conducted by EPA, the
principal threat within the study area is PCBs. PCBs were
detected in Rail Yard soil, buildings, structures, residential
soils, stream sediments, and fish. Ground water sampling results
for PCBs were reported as laboratory values less than the
reliable detection limit but possibly greater than zero. These
values are below the quantification limit which is the lowest
level at which a chemical can be accurately quantified. PCBs
were reported below the level of quantification in wells
containing fuel oil, probably due to cross contamination with the
fuel oil which is known to mobilize PCBs. Lack of quantifiable
presence of PCBs in ground water plus the likelihood of removing
fuel oil that may mobilize PCBs should effectively protect ground
water from increased PCB contamination. Fuel oil which
previously leaked into the ground on-site has resulted in
elevated levels of BTEX compounds on-site. Benzene has been
detected at concentration in ground water that exceeds the HCL
concentration.
The selected remedies are protective of human health and the
environment for the five study areas described in the ROD. The
source control remedies for Rail Yard soils and residential soils
requiring excavation and treatment using stabilization and
solidification will prevent exposure to PCBs through inhalation,
ingestion, and dermal contact. A risk level of approximately
10~5 for PCBs will be obtained for residential soils and rail
yard soils. The solidification/ stabilization process for both
rail yard and residential soils will be conducted in accordance
with the following: the Toxic Substances Control Act (TSCA) of
1976, Subpart B - Manufacturing, Processing, Distribution in
Commerce, and Use of PCBs and PCB Items, 40 C.F.R. S?61.20(c);
TSCA Disposal Requirements, 40 C.F.R. S 761.60(a)(2)(iii); TSCA
Chemical Waste Landfill, 40 C.F.R. 5 761.75, with the exception
of those management controls which are waived under CERCLA $
121(d)(4); the Pennsylvania Erosion Control Regulations, 25 PA
Code SS 102.1 -102.5, 102.11-102.13, 102.22- 102.24; and the'
Pennsylvania Air Pollution Control Act, 25 PA Code SS 123.1,
123.2, 123.41, 127.1, 127.12 and 127.14.
The ground water treatment and fuel oil extraction program shall
reduce levels of benzene in the ground water to the MCL level of
5 ug/1 as required by the Safe Drinking Water Act, 42 U.S.C.
SS 300(f) - 300(j) and 40 C.F.R. S S 141.61 or the background
concentrations of benzene (the Pennsylvania ARAR under 25 PA Code
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§§ 264.90-262.100), §§ 264.97(1), (j) and 264.100(a) (9) ) ,
whichever is more stringent, and shall protect human health and
the environment by treating benzene and by removing fuel oil to
prevent mobilization of PCBs into the ground vater. To the
extent that the MCLs are the ARAR, compliance with requirements
set forth at 25 PA Code Chapter 109, specifically §§ 109.1-109.4
and 109.202 promulgated pursuant to the Pennsylvania Safe
Drinking Water Act, (35 P.S.. §§ 721. -721. 17) , shall be required.
Rail yard building and structures will be decontaminated to
attain ARARs the extent necessary to meet the TSCA disposal
requirements at 40 C.F.R. §761.60.
Excavation of stream sediments will reduce aquatic toxicity and
bioconcentration of PCBs through exposure to contaminated
sediment or through consumption of aquatic organisms.
Environmental damage which may occur during stream sediment
excavation will be mitigated through a restoration program. All
stream remediation will be conducted in accordance with the
following to the extent applicable or relevant and appropriate:
the Fish and Wildlife Coordination Act, 16 D.S.C. §§ 661 et sea. ;
the Endangered Species Act of 1973, 16 U.S.C. §§ 651 e£ sec. ; the
Pennsylvania Erosion Control Regulations, 25 PA Code §§ 102.1
-102.5, 102.11-102.13, 102.22- 102.24; the Pennsylvania Dam
Safety and Encroachments Act of 1978, P.L. 1375, as amended . 32
P.S. §§ 693.1 et sea, and the Pennsylvania Dam Safety and
Waterway Management Regulations, 25 PA Code §5 105.104, 105.106,
105.111, 105.121; the Pennsylvania Clean Streams Law, 35 P.S.
§§ 691.1 to 691.1001 and the National Pollution Discharge
Elimination System, 25 PA Code 92 and the Pennsylvania Water
Quality Standards, 25 PA Code 93.
Implementation of the selected alternative will not pose any
unacceptable short 'term risks or cross-media impacts to the Site
or the community.
g f Attai*iw*flt of Applicflbl^ or Rele
Requirements ot Environntal Lavs
EPA is invoicing a waiver under CERCLA § 121 (d) (4) for certain
landfill requirements as required by TSCA, 40 C.F.R. § 761.75 and
as previously discussed under the Description of Alternatives.
All other ARARs will be met by the selected remedy.
A requirement under environmental lavs may either be "applicable"
or "relevant and appropriate" but not both. Therefore, ARARs are
identified based on a two part analysis. First, a determination
is made as to whether or not a requirement is applicable; then,
if it is not applicable, a determination is made whether it is
nevertheless both relevant and appropriate.
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Applicable requirements are those cleanup standards,
standards of control, and other substantive environmental
protection requirements, criteria, or limitations promulgated
under federal or state lav that specifically address a hazardous
substance, pollutant, contaminant, remedial action, location, or
other circumstance at a CERCLA site.
Ralavant and appropriate requirements are those cleanup
standards of control and other substantive environmental
protection requirements, criteria, or other limitations
promulgated under federal or state lav that, vhile not
"applicable" to a hazardous substance, pollutant, contaminant,
remedial action, location or other circumstance at a CERCLA site,
address problems or situations sufficiently similar to those
encountered at the CERCLA site, that their use is veil suited to
the particular site.
To Be Considered Material. (TBCs) are non-promulgated
advisories or guidance issued by federal or state governments
that are not legally binding and do not have the stature of
ARARs. However, in many circumstances, TBCs can be considered
along with ARARs as part of the risk assessment and may be used
in determining the necessary level of cleanup or protection to
human health or the environment.
There are three types of ARARs considered in the FS. These three
types are chemical-specific, action-specific, and
location-specific ARARs.
1. Chemical Specific ARARs
Chemical specific ARARs are health or risk based numerical
values, which, when applied to Site specific conditions, result
in the establishment of numerical values vhich designate the
amount of concentration of a chemical that may be acceptable in
the media of interest. The following are chemical-specific ARARs
for the Site:
• Safe Drinking Water Act 42 U.S.C. §§ 300f - 300j; and 40
C.F.R. Part 141.61 pertaining to maximum contaminant levels for
groundvater;
• Pennsylvania Hazardous Waste Management Regulations, 25 PA
code §§ 264.90-264.100, specifically §§ 264.97(1), (j) and •
264.100(a) (9) pertaining to remediation of groundvater to
background;
• Pennsylvania Safe Drinking Water Act, 35 P.S. §§. 721.-
721.17; and 25 PA Code Chapter 109, §§ 109.1-109.4 and
§§ 109.201, 109.202 pertaining to maximum contaminant levels for
drinking vater supplies;
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The selected remedy shall be designed to achieve compliance with
the chemical specific ARARs related to groundwater at the Site.
The Safe Drinking Water Act specifies MCLs for drinking water at
public water supplies. The MCL for benzene is 5 ug/1.
The Commonwealth of Pennsylvania standards specify that all
ground water containing hazardous substances must be remediated
to "background" quality pursuant to 25 PA Code 264.90-264.100,
and in particular, 25 PA Code 264.97(i), (j), and 264.100(a)(9).
The Commonwealth of Pennsylvania also maintains that the
requirement to remediate to background is found in other legal
authorities. The background level shall be attained as set forth
under the description of the selected remedial alternative unless
EPA determines that attaining such level is technically
impracticable, or such level is otherwise waived under CERCLA
§ I21(d)(4).
2. Action-Specific ARARs
•
Action specific ARARs are technology or activity-based
requirements or limitations on actions taken with respect to
hazardous wastes. Any RCRA hazardous waste generated on-site and
transported off-site for treatment, storage or disposal should be
managed pursuant to RCRA Subtitle C, 40 C.F.R. Parts 262,
Standards Applicable to Generators of Hazardous Waste, 263,
Standards Applicable to Transporters of Hazardous Waste, and 264,
Regulations and Standards for Owners and Operators of Hazardous
Waste Treatment, Storage and Disposal Facilities and the
Department of Transportation Rules for Hazardous Materials
Transport, 49 C.F.R. Parts 107 and 171-179.
The following are action-specific ARARs for the Site. These
ARARs would be applicable for recovered fuel oil and any other
RCRA characteristic waste generated during the remedial action.
• RCRA Land Disposal Restrictions, 40 C.F.R. Part 268,
Subpart D;
• The Toxic Substances Control Act (TSCA) of 1976, 15 U.S.C.
§§ 2601 to 2671, and regulations thereunder at Subpart B -
Manufacturing, Processing, Distribution in Commerce, and Use of
PCBs and PCS Items, 40 C.F.R. §76l.20(c);
• TSCA Disposal Requirements, 40 C.F.R. S 761.60(a) (2).(iii);
• TSCA Incineration, 40 C.F.R. S 761.70;
• TSCA Chemical Waste Landfill, 40 C.F.R. S 761.75;
• The Pennsylvania Air Pollution Control Act, 25 PA Code
§S 123.1, 123.2, 123.41, 127.1; 127.12; and 127.14 pertaining to
fugitive dust and particulate emmissions during remediation;
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• Occupational Health and Safety Act, 29 C.F.R. Parts 1904,
1910, and 1926, 29 U.S.C. §§ 653-657, pertaining to worker
protection during remediation;
• Safe Drinking Water Act, 42 U.S.C. § 300h(d), [SDWA
§ 1421]; and 40 C.F.R. Part 144 pertaining to underground
injection of fluids.
The selected remedy shall be designed to achieve compliance with
the action-specific ARARs related to soils at the Site.
The Occupational Health and Safety ACT (OSHA), 29 C.F.R. Parts
1904, 1910, and 1926, provides occupational safety and health
requirements for workers involved in field construction or
operation and maintenance activities and is applicable to the
selected remedy.
Pennsylvania Solid Waste Disposal Regulations, 25 PA Code
§§ 260-264 are relevant and appropriate to any hazardous waste
generated on-site and transported off-site for treatment,
storage, or disposal and for design and operation of the on-site
containment cell.
The Toxic substances Control Act (TSCA) of 1976, 15 U.S.C.
§§ 2601 to 2671, establishes regulations at 40 C.F.R. Part 761
for disposal and storage of PCB-contaminated materials. TSCA is
applicable to remediation of PCS contaminated waste where
disposal of material contaminated with PCBs at concentrations of
50 ppm or greater occurred after February 17, 1978. TSCA
requirements are considered relevant and appropriate regardless
of the date of disposal. Any PCB contaminated material taken
off-site during remediation must meet applicable TSCA disposal
requirements.
The PCB Disposal Requirements promulgated under TSCA are ARARs
for rail yard soil because the selected remedy involves treatment
and disposal of soils contaminated with PCBs in excess of 50 ppm.
Under TSCA, soils contaminated with PCBs may be disposed of in an
incinerator, chemical waste landfill, or may be disposed of by an
alternate method which is a destruction technology that achieves
an equivalent level of performance to incineration [40 C.F.R.
§ 761.60(a)(4) and 761.60(e)].
The Regional Administrator is exercising the waiver authority of
CERCLA §121(d)(4), 42 U.S.C. §9621(d)(4), and the National
contingency Plan (NCP), §300.430(f)(1)(ii)(C), and is waiving
certain requirements of the TSCA chemical waste landfill. The
Regional Administrator hereby determines that, for the following
reasons, the requirements of 40 C.F.R. 761.75 (t>) (1), (2), (3)
and (7) are not necessary to protect human health or the
environment from PCBs, and that the recommended alternative will
attain a standard of performance that is equivalent to that
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required under TSCA standards and regulations. These ARARs are
waived for the following reasons. In this case, placement of
treated solidified soil in a containment cell with impermeable
cap to minimize infiltration, ground water monitoring in the
immediate vicinity of the containment cell [(40 C.F.R.
§761.75(b)(6)], and compliance with performance standards and
other ARARS in the ROD will satisfy the requirements of a
chemical waste landfill," thereby allowing for a CERCLA §
121(d)(4) waiver.
The requirement for a synthetic membrane liner and leachate
collection system is waived because there is no hydraulic
connection between the solidified mass and the ground water or
surface water, and because the performance standard for the
solidified treated soil will require a hydraulic conductivity of
10~7 cm/sec, equivalent to that required by a synthetic membrane
liner, and will minimize leaching of PCBs from the solidified
material. The water table is 35 to 50 feet below the ground
surface, and infiltration of PCBs to .the ground water will be
prevented by binding the PCBs in a solidified mass, and by
implementing a ground water monitoring program on a long-term
basis to detect any leaching of PCBs. The lack of quantifiable
levels of PCBs in ground water plus the likelihood of removing
the fuel oil that may mobilize PCBs should effectively protect
ground water from increased PCB contamination.
The hydrologic requirement that the landfill must be fifty feet
above the historic high water table is waived because it is
extremely unlikely that the solidified soils will ever come in
contact with the ground water since the ground water is 35 to 50
feet below the ground surface and the permeability of the natural
soil is in the range of 10~5 to 10~6 cm/sec as reported in the
FS. The rail yard is not within a 100-year flood plain.
In addition, with regard to fuel oil contaminated soil, the area
is contained with an asphalt cover, is currently being remediated
by a ground water and fuel oil recovery system, and is located at
depths of 20 feet or more so as to make excavation technically
impracticable.
These factors ensure that at this Site there will not be an
unreasonable risk of injury to health and the environment by
waiving the above requirements.
3. Location Specific ARARs
Location-specific ARARs are restrictions placed on the
concentration of hazardous substances solely because they occur
in a special location. The following are location-specific ARARs
for the Site:
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• The Fish and Wildlife Coordination Act, 16 U.S.C. § 661 <=,_
secj. ;
• The Endangered Species Act of 1973, 16 U.S.C. § 1651 et
seg.;
• The Pennsylvania Erosion Control Regulations, 25 PA Code
§§ 102.1-102.5, §§ 102.11-102.13, and §§ 102.22-102.24;
• The Pennsylvania Dam Safety and Encroachments Act of 1978,
P.L. 1375, as amended. 32 P.S. §§ 693.1 et sea.; and the
Pennsylvania Dam Safety and Waterway Management Regulations, 25
PA Code Chapt. §§ 105.1 et seg.. pertaining to wetlands
permitting;
• The Pennsylvania Clean Streams Law, 35 P.S. §§ 691.1 to
691.1001; and the National Pollution Discharge Regulations at 25
PA Code 92 pertaining to point source discharges to streams,
wetlands permitting; and 25 PA Code 93 pertaining to Water
Quality Standards for discharge to streams;
• 25 PA Code § 269(b)(l) and (2) describes requirements for
building a facility within a protected river corridor.
• The Clean Water Act, 33 U.S.C. S 1344; and 33 C.F.R. Part
330 pertaining to permitting of wetlands;
The selected remedy shall be designed to achieve
location-specific ARARs for the Site.
The Fish and Wildlife Coordination Act, 16 USC §661 et. see..
enacted to protect fish and wildlife due to the control or
structural modification of a natural stream or body of water, is
relevant and appropriate to stream sediment remediation.
The Endangered Species Act of 1973, 16 USC $1651 et. sea..
provides a means for conserving various species of fish,
wildlife, and plants that are threatened with extinction. The
Endangered Species Act will be applicable if a determination is
made that endangered species are present or will be affected by
the remedial alternative.
The Pennsylvania Erosion Control Regulations, 25 PA code Chapter
§§ 102.1-102.5, 102.11-102.13, 102.22-102.24, regulate erosion
and sedimentation control. These regulations are applicable to
the regrading and excavation activities associated with the
selected remedial alternative at the rail yard and in the
residential areas.
The Pennsylvania Dam Safety and Encroachments Act, Act of 1978,
P.L. 1375, as amended. 32 P.S. SS 693.1 e£. seq.. and the
Pennsylvania Dam Safety and Waterway Management Regulation,
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Chapter 105, 25 PA Code §§ 105.1 et. seq. apply to stream
relocation and any other stream encroachments and to wetland
protection.
4. To-Be-Conaidered (TBC)
To-Be-Considereds are non-promulgated advisories or guidance
issued by Federal or State government that are not legally
binding and do not have the status of potential ARARs. However,
in many circumstances, TBCs will be considered along with ARARs
as part of the Site risk assessment and may be used in
determining the necessary level of cleanup for protection of
health or the environment. The following are TBCs for the Site:
• "CERCLA Compliance with Other Laws" Manual
(EPA/540/G-89/006;
• "Guidance on Remedial Actions for Superfund Sites with PCB
Contamination," US EPA, OSWER Directive: 9355.4-01FS, Office of
Emergency and Remedial Response Hazardous Site Control Division
(OS-220), August 1990;
• The Toxic Substances Control Act, Part 761, Subpart G, PCB
Spill Cleanup Policy, 40 C.F.R. S 761.120;
• "A Guide to Selecting Superfund Remedial Actions," US EPA,
OSWER Directive: 9355.0-27FS, Office of Emergency and Remedial
Response Hazardous Site Control Division OS-220, April 1990;
• Executive Order 11988, 40 C.F.R. S 6, Appendix A,
concerning Federal wetlands policies.
In order to assist in the identification and assessment of ARARs,
EPA has developed the "CERCLA Compliance with Other Laws" Manual
(EPA/540/G-89/006). In addition, EPA has issued OSWER Directive
No. 9355.4-01, August 1990, "Guidance on Remedial Actions for
Superfund Sites with PCB Contamination" (PCB Guidance Document).
The PCB Guidance Document identifies potential ARARs and TBC
criteria pertinent to CERCLA sites with PCB contamination and
addresses their integration into the RI/FS and remedy selection
process.
The TSCA PCB Spill Cleanup Policy [40 CFR $761.60(d)] addresses
improper disposal of PCBs as intentional (as well as
unintentional) spill, leaks, and other uncontrolled discharges of
PCBs at concentrations of 50 ppm or greater. While the TSCA
PCB spill cleanup policy is not a potential ARAR, it does
identify cleanup standards and is a TBC. These guidelines are to
be applied on a case-by-case basis. For example, the selected
remedy identifies a cleanup standard of 10 ug/100cm2 for PCB
contaminated surface areas in the rail yard car shop building
based on the Spill Cleanup Policy. EPA does not believe,
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however, that the spill cleanup policy standards for remediation
of residential soils which requires remediation to 10 ppm with a
10 inch soil cover will adequately protect human health and the
environment and has recommended lower cleanup standards in the
ROD based on EPA's risk assessment for the Site.
C. Cost Effectiveness
The selected remedy is cost-effective in providing overall
protection in proportion to cost, and meets all other
requirements of CERCLA. The NCP, 40 CFR §§ 300.430(f)(ii)(D),
requires EPA to evaluate cost-effectiveness by comparing all the
alternatives which meet the threshold criteria - protection of
human health and environment and compliance with ARARs - against
three additional balancing criteria: long-term effectiveness and
permanence; reduction of toxicity, mobility or volume through
treatment; and short-term effectiveness. The selected remedy
meets these criteria and provides for .overall effectiveness in
proportion to its cost.
The estimated present worth cost for all the selected remedies is
$28,268,000. A cost estimate is presented in Table 4.
Excavation and treatment of quantities of soil and sediments
different than the quantities estimated in the FS will change the
present worth cost proportionately.
EPA has determined that the selected remedies represent the
maximum extent to which permanent solutions and treatment
technologies can be utilized while providing the best balance
among the other evaluation criteria. Of those alternatives
evaluated that are protective of human health and the environment
and meet ARARs, the selected remedies provide the best balance
with regard to long-term and short-term effectiveness and
permanence, cost, implementability, reduction in toxicity,
mobility, or volume through treatment, State and community
acceptance, and preference for treatment as a principal element.
Stabilization/solidification of contaminated soils and sediments
is a treatment technology which permanently reduces the mobility
of PCBs through immobilization and physical encapsulation.
Although the selected alternatives do not provide as great a
degree of reduction of toxicity and mobility as the incineration
and KPEG technologies, stabilization/solidification will reduce
the risks associated with direct contact with PCBs to a greater
degree than containment only. The selection of treatment rather
than containment of PCB-contaminated soil and sediment is
consistent with Superfund program policy for wastes that
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represent a principal threat at the Site.
The ground water treatment system will provide for recovery of
fuel oil and treatment of ground water to the maximum extent
practicable. Decontamination of rail yard buildings and
structures will effectively provide treatment of all contaminated
surface areas that pose a direct threat to human health.
E. Preference for Treatment as a Principal Element
The selected remedies satisfy the statutory preference for
treatment as a principal element.
XII. DOCUMENTATION OF SIGNIFICANT CHANGES
The following significant changes have been made to the Selected
Remedies from the preferred alternative described in the Proposed
Plan.
1) The selected alternative for remediation of rail yard soils
has been clarified to indicate that additional treatability
studies will be conducted. The reasons for requiring additional
treatability studies are discussed in the ROD. The cost of
remediation of rail yard soil has been increased by $3,240,000 to
construct a containment cell. This cost is based on comments
received from the PRPs and was not included in the FS cost
estimate.
2) The selected alternative for remediation of rail yard soils
has been clarified to indicate that fuel oil soils will not be
excavated as long as the ground water and fuel oil recovery
systems are effectively operated and impermeable asphalt cover
remains in place as described in the ROD.
3) The selected alternative for remediation of stream sediments
will require additional stream monitoring and less extensive
excavation to achieve the l ppm cleanup standard. This change was
made in response to several comments received by the Agency.
74
80
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Table 1
Summary of PCS Concentration for Selected Media Locations
Location
Range of Detected
PCS Concentration1
Rail Yard Soil 0.84 - 6000 ppm
Residential Soil 0.15 - 21 ppm
Carshop Indoor Surfaces 0.6 - 823 ug/100 cm2
Cleanup Standard
25 ppm
2 ppm
10 ug/100 cm2
Stream Sediments in
Tributaries
-North Valley Road
-Cedar Hollov Road
-Hollow Road
0.11 - 5.0 ppm
1.3 - 28 ppm
1.3 - 190 ppm
1 ppm
1 ppm
l ppm
^Reported as Arachlor 1260
82
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2
Kay Risk Terms
Carcinogen: A juestanca tnat increases tr>s maasncs of cancsr.
CnronicOaay Irrtaka (COI): The average amount of a cnemrcai m csmaa wirn an
Ticrvtduai on a caily Basis over a suostannai portion of a lifetime.
Chronic Exposure: A persistent recurring, or long-term exposure. Chronic «xeosure
may rtsuit m nssitn tfftcts fsucn as cancsr) mat art osiaysd m onset occumng ;ong
ansr exposure cessso.
Ths opportunity to receive a doss tnrougn direct eomact wnn a cntmicat or
medium containing a cnemicsi.
Exposure Assessment: The oroeess of dsscnbing, for s population at nsk. me
amounts of cnemicsts to wnicn individuals are exposed, or me distnouoon of exposures
s population, or me average exposure of an entire population.
Hazard Index: An EPA memod used to assess me potential noncaronogsmc risk. Ths
rano of ma COI to me cnronic RfO (or otnsr suitse* toxicrty value for noncaronegens) is
calculated, if it is isss man ens. msn me exposurs ropressmso by me COI is judged
unlikely to produce an adverse noncarortogenw effect A cumulative, endpomt-speofio
HI can siso be caieutatsd to evaluate me risks possd by exposure to more msn ons *
cnsrmeai by summing me COI RfO ratios for a* me cnsrmcats of intarest exert s similar
•
-------
Table 3
Parameters Used in Exposure calculations
Parameter
(1) Amount of soil
ingested or fish
consumed
(2) Percent Absorbed
(3) Body Weight
(5)' Exposure Duration
(years/lifetime)
Soil Ingestion
Rail Yard
50 mg/day
loot
70 Kg
(4) Exposure Frequency 250 days/yr
25
Soil Ingestion
Residential
100%
70 Kg (adult)
15 Kg (child)
350 days/yr
24 (adult)
6 (child)
Fish
*oo ZSS !££>' °-°54 K"-al
50%
70 Kg
350 days/yr
30
84
-------
T&bla 4 Cost Summarv
Rail Yard Soil
Residential Soil2
Building &
Structures
GW & Fuel Oil
Treatment
Stream/Sediments2
Capital
$18,204,275
$1,196,000
$260,000
-0-
$5,701,720
Annual
0«M
$138,250
-0-
$235, 9501
•
$120,000
-0-
Present
worth
$19,507,375
$1,196,000
$731,905
$1,131,120
$5,701,720
1 Cost of implementing worker protection program for
2 years until rail yard closes.
, Based on FS estimate.
85
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SITE LOCATION
PAOLI RAIL YARD
PAOLI, PA.
SOURCE: US6S TOPOGRAPHIC QUADRANGLES
MALVERN, PA. (IS55J 8 VALLEY
FOR6C, PA. 7.5 MINUTE SERIES
GROUNDWATER
TECHNOLOGY. INC
86
POOR QUALITY
ORIGINAL
-------
wort' MTMICD P«OP{nr» ntn INCLUOCO IN IMC
r*oti Ma MNO MCVISCO sow MIIMMCO en 21 juu 1107
SURFACE FEATURES ON THE
HAIL YARD
PAOI.I RAILVARO
PAOLI, FA.
-/ /
~|f I (.HilllNKU'AII l<
'!. ' II ( IINiM (M,V lINi ,-
-------
SOURCE USGS TOPOGRAPHIC
MAtVEP-N, PA (I9S5! 8
VALLEY FbRGE, PA
75 MINUTE SERIES
RAIL YARD AND STUDY AREA
BOUNDARY-COUNTY SCALE
FAOLI RAil YARD
PAOU, PA
in
- ' '' =i! TECHNOLOGY
88
POOR QUALITY
ORIGINAL
-------
J^^ -~-tJ_ir^>
DRAINAGE FROM RAH. YARD PRIOR TO 1986
EROSION CONTROL FEATURES
PAOLI HAIL YARD
PAOLI. PA
/;;
1 -Hi MINIHVA II If
I I < MNi i| ( ii.V IN,
-------
L
.V
PCS ANALYTICAL RESULTS
^SURFACE WATER S
SAMPLES COLLECTED
DURING AVERAGE
PLOW CONDITIONS
PAOLI RAIL YARD
PAOLI, PA.
,a>\
Q.001U
(300)
90
-------
i
A
PCS ANALYTICAL RESULTS
FOR SURFACE WATER
SAMPLES COLLECTED
AFTER A RAIN EVENT
PAOLI RAIL YARD
PAOLI, PA.
91
-------
IO
NJ
S 7°
00
li
•I 000009/ |,,4/|
• I
0000004 ii,,,,,
•MII34
0000*14 (1,10,
ANALYTICAL PCB RESULTS
FOR AIR SAMPLING EVENTS
PAOLIRALYARD,
I'AOl I, PA
All HI W* (•> PI H AttiM I IIW« (T«IIOM LOCATION!
- M.»,i«»n «i,IK:ip«l«a PCB l,
I |«'IK»IIN|IW/AMH
"IHMNOMM.V IN,
C
n
10
^j
-------
Or )
M
n>
WELL LOCATIONS/AB PLAN VIEW
FOR CROSS-SECTIONS
I'AOU R/KII YAHD
I'AOl.1. I'A
us
ui
O)
-------
(£>
Rl GROUNOWATCR SAMPLING RESULTS \
SECOND ROUND (COLLECTEO-6/26/89 "6/28/89
PACLI R««L YARD
-------
:J
o
II
M4MU\\* • MOMIIONIMOilL
MSI HOI MMniD, Mtl HOI
IN scon or MM*
MS HUI SAUntDDX lumtill.
Of rMAM MIM*IU>n*t I*
Nutt -All M SIM ISMfMlftCMN
t*«m< *»••»—- ------
^ Ml CI B HI iin
'^ OU/tl S*M**I I
Rl GROJNDWATER SAMPLING RESULTS
FIRST ROUND (COLLECTED- 5/31/89-6/E/89)
1 I'AOI I RAIL YARD
HAOl I, PA
I 1 IfUlf
-------
^'^L.-frb^S?:...',-- ./ ^^^^
^ ' V.-N-' ,y*&^^
;a §i '-^ ^^rz
^ 5
- it»T»:c .••»t«Ttn*ri xn
- 3- f:s» s«
- -
CS^.^yrnfl." /r:^ -:
-"*!wI- • :f ?&.-^££&t^i&*>~5^:"^
wag^M*,..£3«2
rAi VSTATION 11-~.
.rT**_T*- 0.1 _. .— •.
GROUNDWATER
TECHNOLOGY. INC. fig u re
96
QR1G1KAL
-------
8Q.UED WORMS COLLECTED
12«8
CONCENTRATION. MG/KG
00«a FULL WORM 0.065
EMPTY WORM 0.091
<10M) FULL WORM 0.805
doan EMPTY WORM
PULL WORM
EMPTYWORM
_
PULL WORM 0238
) PULLWORM o 32,
50) EMPTY WORM 0.27
t-j PfattJNC
1' ' JTrn-~ ~~ :••:
-------
COLLECTED
VALLEY CREEK AND LTTTLE VALLEY CREEK
AROCLOR 1260 UNLESS OTHERWISE NOTED
' - AROCLOR 1254
"- AROCLOR 1248
__12« CONCENTRATION . MG/KG
FT.
\
TROUT FILLET O.S46 (901) 0.52 (90«O)
0.356 ' 0.14 •
SUCKER FILLET 0.322 (902) 0.266 (905O)
0.147 • fl.052 •
SUCKER GRIND 0.706 (903) 0.669 (9060)
0.493 * 0.059 • ^
\
'TROUT FILLET 0.522 (3X:
0 28 '
2* SUCKER FILLET 0.962 (W)
0.394 •
SUCKER GRIND 1.757 (S3r
1.332-
\\
j TROUT FILLET 0.112
; 0.107'
I SUCKER FILLET 0.19
I 0.24 *
: SUCKER GRIND 0.823
0.366*
(90?)
\
5t/ TROUT FILLET 0.708 <
0.288*
'SUCKERFILLET 0.891 (BM)
0.288*
^SUCKER GRIND 1.397 (909
^ 0.95*
lO1^ _^
; TROUT FILLET 0.138 (»i«
3.184* im\
SUCKER FILLET 0.101 (911?'
0.12i •
KER GRIND 0.244 (919
13 i
\\C
%\
i
/
\
>
98
Figure 13
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