PB94;9j63903
EPA/ROD/R03-94/180
July 1994
EPA Superfund
Record of Decision:
Revere Chemical Site,
Nockamixon,
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V
RECORD OF DECISION
REVERE CHEMICAL SITE OPERABLE DNIT OHE
DECLARATION
SITE NAME AND LOCATION
Revere Chemical Superfund Site
Nockamixon Township, Bucks County, Pennsylvania
STATEMENT OF BASIS AND PURPOSE
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This decision document presents the selected remedial action for
the Revere Chemical Site ("the Site"), located on the southeast
side of U. S. Route 611, just north of Route 412 and south of the
town of Revere, Pennsylvania. This remedial action was chosen in
accordance with the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980 ("CERCLA"), as amended by
the Superfund Amendments and Reauthorization Act of 1986 ("SARA11)
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 remedial action for this Site. The information
supporting this decision is contained in the Administrative
Record for this Site.
The Commonwealth of Pennsylvania has indicated concurrence with
the selected remedy. A letter of concurrence has not been
received as of the date of the signing of this Record of
Decision.
ASSESSMENT OF THE SITE
Pursuant to duly delegated authority, I hereby determine,
pursuant to Section 106 of CERCLA, 42 U.S.C. 5 9606, that actual
or threatened releases of hazardous substances from this Site, if
not addressed by implementing the response action selected in
this Record of Decision ("ROD"), may present an imminent and
substantial endangerment to the public health, welfare, or the
environment.
DESCRIPTION OF THE SELECTED REMEDY
The contaminated media at the Site are divided into Operable
Units as follows:
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•OU1 Contaminated soil areas
Solid waste and miscellaneous debris
•OU2 Ground water
Mercury-contaminated sediments
This ROD addresses the first Operable Unit. EPA anticipates
issuing a final ROD for Operable Unit Two within the next year.
The selected remedial action for the first Operable Unit is a
final remedy and will address contaminated soil and solid waste
and miscellaneous debris on portions of the Site. The volatile
organic ("VOC") soil contamination represents the principal
threat. Therefore, treatment of the VOC-contaminated soil will
be required.
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The selected remedy includes the following major components:
• Offsite disposal of solid waste and debris
• Treatment of VOC contaminated soil by vacuum
extraction
• Source containment by slurry wall
• Source containment by capping
• Fencing to limit access to capped areas
• Site restoration by revegetation
• Deed restrictions
• Long-term ground water monitoring
STATUTORY DETERMINATIONS
The selected remedial action is protective of human health and
the environment, complies with federal and State requirements
that are legally applicable or relevant and appropriate to the
remedial action, and is cost-effective. This remedial action
utilizes permanent solutions and alternative treatment (or
resource recovery) technologies to the maximum extent
practicable, and satisfies the statutory preference for remedies
that employ treatment which reduces toxicity, mobility, or volume
as a principal element.
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Because this remedy, will result in hazardous substances remaining
onsite, a review by EPA will be conducted within five years after
initiation of remedial action, and every five years thereafter,
as required by Section 121 (c) of CERCLA, to provide adequate
protection of human health and the environment.
:anley L. Easkowski Date
Acting Regional Administrator
Region III
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TABLE OF CONTENTS
I. SITE IAMB, LOCATION, AND DESCRIPTION 1
II. SITE HISTORY AND ENFORCEMENT ACTIVITY 1
III. HIGHLIGHTS OF COMMUNITY PARTICIPATION 4
IV. SCOPE AND ROLE OF THE RESPONSE ACTION WITHIN SITE
STRATEGY 4
V. SUMMARY OF SITE CHARACTERISTICS AND EXTENT OF
CONTAMINATION 5
VI. SUMMARY OF SITE RISKS • 11
VII. DESCRIPTION OF REMEDIAL ACTION ALTERNATIVES 16
ALTERNATIVE 81: NO ACTION/INSTITUTIONAL CONTROLS . 18
ALTERNATIVE 82: EROSION CONTROL CAP/OFFBITE
SOLID WASTE DISPOSAL 19
ALTERNATIVE 83: EROSION CONTROL CAP/CLAY CAP-SLURRY
WALL/VACUUM EXTRACTION/OFF8ITE SOLID WASTE DISPOSAL 20
ALTERNATIVE 84: CLAY CAP/SLURRY WALL/OFF8ITE SOLID
WASTE DISPOSAL 21
ALTERNATIVE 85: IMPERMEABLE CAP/SLURRY WALL/OFFSITE
DISPOSAL 22
ALTERNATIVE 86: CLAY CAP/SLURRY WALL/VACUUM
BXTRACTION/OFF8ITB DISPOSAL 23
ALTERNATIVE 87: EROSION CONTROL CAP/LOW TEMPERATURE
THERMAL 8TRIPPING/OFF8ITE DISPOSAL 23
ALTERNATIVE 88: LTT8/EROSION CONTROL CAP/ON8ITE
DISPOSAL 24
ALTERNATIVE 89: VACUUM EXTRACTION/SOIL STABILIZATION
EROSION CONTROL CAP/OFF8ITB DISPOSAL - 25
VIII. SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES . 26
IX. THE SELECTED REMEDY AND PERFORMANCE STANDARDS .... 32
X. STATUTORY DETERMINATIONS 37
XI. EXPLANATION OF SIGNIFICANT CHANGES . 41
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RECORD OF DECISION
REVERE CHEMICAL SITE OPERABLE UNIT
DECISION SUMMARY
I. SITE HAKE, LOCATION, AND DESCRIPTION
The Revere Chemical Site (the "Site") is located southeast of
U.S. Route 611, north of Route 412 and south of Revere in
Nockamixon Township, Bucks County, Pennsylvania. The Site is
located on an approximate 113-acre parcel of property. (Figure 1,
Site Vicinity Map) It includes two unnamed tributaries of Rapp
Creek. The tributaries to Rapp Creek predominantly flow over
bedrock. Rapp Creek is a tributary to Tinicum Creek, which is a
tributary to the Delaware? River. The Delaware River is •
approximately 4 miles from the Site. The Pennsylvania Scenic
Rivers System has nominated Rapp Creek as part of the system.
Rapp Creek has a nominated designation of Scenic, First
Priority - Group A, and is in Water Quality Group 1. The area
surrounding the Site includes recreational streams, forests,
fields, and Pennsylvania State Game Lands. Nockamixon State Park
is located approximately 4,700 feet southwest of the Site.
Nockamixon Lake is located within the boundaries of the park and
has a surface area of 1450 acres. State Game Land is located
approximately 4,700 feet northeast of the Site. The Site is
bounded on the south, east, and west by farm land. Cotner
Trailer, a commercial operation that manufactures horse trailers,
abuts the Site to the north.
The Site is situated in the portion of the Piedmont Physiographic
province designated as the Piedmont Upland. The area is
characterized by gently rolling hills and sloping topography.
Elevations at the Revere Chemical Site range from approximately
520 feet above mean sea level at the north corner of the Site to
approximately 390 feet above mean sea level along Rapp Creek and
its tributaries at the southwest property boundary. Two types of
wetlands, Riverine and Palustrine, are found on the Site. The
endangered floral species Tomanthra auriculata (false foxglove)
is also found on Site.
The Site is primarily drained by the east and west tributaries to
Rapp Creek that join in the southeast portion of the Site and
discharge to Rapp Creek approximately 300 feet beyond the
property boundary.
The primary source of drinking water for the businesses and homes
surrounding the Site is ground water. Private wells pump ground
water from the Lockatong Formation.
II. SITE HISTORY AND ENFORCEMENT ACTIVITY
Facility documents regarding the Revere Chemical Company were
destroyed in a 1984 fire on the Site. Therefore, documents from
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EPA, FADER and the Bucks County Department of Health files
provided most of the information regarding the historical layout
of the Site and facility processes.
Beginning in approximately 1963, Echo, Inc. operated a
reclamation facility. Echo's operations included metals
reclamation from printed circuit boards, recycling of spent
chromic acid, recovery of copper from plating solutions and
production of copper chemicals. From 1963 to 1969 the Site was
operated at various times by Echo, Inc., the DeRewal Chemical
Company and the Revere Chemical Company. The companies arranged
for the transport and onsite treatment of hazardous substances,
including waste metal plating, and etching solutions.
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The area of the Site used for the processing of materials covered
approximately 25 acres. The process area, now enclosed by a
fence, contains several buildings and structures that were used
during the metals reclamation operations. Also included are: the
remains of 19 storage and/or process lagoons; the remains of a
waste lagoon; and a fresh water pond. The East and South Spray
fields are located outside the process area. They were used for
liquids disposal during the metal reclamation operations.
Detailed descriptions of past Site operations are unavailable.
Similarly, no detailed records regarding the types and quantities
of sludge and plating materials stored on the Site during the
years of operation are available. .However, samples of materials
in the process basins and lagoons on Site were collected by the
Commonwealth of Pennsylvania, Department of Health ("PADOH"),
PADER's predecessor, in March 1970. On the basis of this data,
it was concluded that facility processes used chromic acid,
copper sulfate, ammonia, ferric chloride, nickel, and sulfuric
acid solutions.
In 1968, the Bucks County Department of Health determined that
the facility had never submitted the required Pollution Incident
Prevention Plan. Subsequent inspections revealed that waste
material from the facility was escaping from the processing and
holding lagoons on Site, and was entering the unnamed tributaries
of Rapp Creek. The State and County Health Department took
enforcement action against the company in an attempt to bring
them into compliance with existing laws. The operators abandoned
the Site in December 1969.
PADOH performed a response action at the Site during 1970 and
1971. An estimated 3.5 million gallons of waste sludges and
liquids were removed.
Pumpable sludges were removed and disposed of at sea. The
remaining sludges were fixed with lime, sodium sulfide and sodium
sulfite, mixed with native soils, and buried onsite in process
lagoons, and storage lagoons. As a result of this remedial
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action, the 25-acre portion of the Site where process operations
occurred (the process area) has been extensively disturbed. No
process or storage lagoons remain. Drums were reported to have
been crushed and buried in former storage lagoon C and former
process lagoon 7 during this action. (Figure 2, Site Features)
Some of the lagoons were closed by the operator during the period
of Site operation and the remainder have been closed during the
remedial action by the PADOH. Present ground cover in the
process area consists of bedrock fragments, soil, and
miscellaneous debris (trash, uprooted brush, and small trees).
For the most part, the ground surface is devoid of vegetation.
The remaining 88-acre portion of the Site that was not used for
metal reclamation is mostly vegetated.
The U.S. EPA performed additional response work at the Site from
March 28 through April 17, 1984. This included the removal of 30
drums containing chromic acid and etching wastes, and 30 cubic
yards of chemical solids from surface soils and the laboratory.
Liquid wastes went to Frontier Chemical in Niagara, New York, and
solid wastes went to Fondessy in Oregon, Ohio.
The Site was listed on the National Priorities List ("NPL") on
July 22, 1987. The NPL is a list of hazardous waste Sites across
the country in need of remedial evaluation and response. The
Site scored 31.31 under EPA's Hazard Ranking System.
EPA entered into an Administrative .Consent Order in December 1988
to conduct a Remedial Investigation and Feasibility Study
("RI/FS11) with the following Respondents: AT&T Technologies,
Inc.; Carpenter Technology Corporation; International Business
Machines Corporation; and Yates Industries, Incorporated.
Installation of an 8-foot-high security fence was completed
around the process area during the Phase I RI on October 4, 1989.
EPA issued an Administrative Order for Response Action to the
Potentially Responsible Parties ("PRPs"), noted above, as well as
a number of other PRPs in December 1991. This order required the
removal of excavated drums and associated wastes staged onsite
during the RI and the implementation of soil erosion and
sedimentation controls. Wastes were removed from the primary
staging area and the four temporary staging areas depicted on
Figure 5
A Phase II RI was conducted to fill in data gaps and complete the
information collected in Phase I. EPA released the Phase II
RI/FS reports and the Proposed Plan for the Site on July 28,
1993. The thirty day public comment period was extended from
August 26 to September 25 providing a total of 60 days for public
comment.
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III. HIGHLIGHTS OF COMMUNITY PARTICIPATION
A Community Relations Plan for the Revere Chemical Site was
completed in June 1989. This document lists contacts and
interested parties throughout government and the local community.
It also establishes communication procedures to ensure timely
dissemination of pertinent information. The RI/FS report and
the Proposed Plan for the Site were released to the public on
July 28, 1993, in accordance with Sections 113(k)(2)(B), 117(a),
and 121(f)(l)(G) of CERCLA, 42 U.S.C. SS 9613(k)(2)(B), 9617(a),
and 9621(f)(1)(G). These and other related documents were made
available in the Administrative Record located at the U.S. EPA
Region III Office, 841 Chestnut Building, Philadelphia,
Pennsylvania, 19107; and at the Site Repositories: Nockamixon
Township Building, Center Hill and Lake Warren Roads, Ferndale,
Pennsylvania 18921; Bucks County Free Library, 150 South..Pine
Road, Doylestown, Pennsylvania, 18901, and Bucks County Free
Library, 229 California Road, Quakertown, Pennsylvania, 18951.
A public meeting was held on August 12, 1993 to discuss the
results of the RI/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 three local newspapers of
general circulation: The Morning Call (July 25, 1993); The Daily
Intelligencer (July 28, 1993); and The Quakertown Free Press
(July 30, 1993). Additionally, copies of the Proposed Plan were
mailed to many residences in the nearby vicinity of the Site and
to other interested parties on the Site mailing list. EPA
notified the public of the 30-day extension to the public comment
period by placing a display advertisement in the Daily
Intelligencer on September 1, 1993.
In accordance with 40 C.F.R. S 300.430 (f)(3)(F), all significant
comments on the Proposed Plan which were received by EPA prior to
the end of the public comment period, including those expressed
orally at the public meeting, are addressed in the Responsiveness
Summary which is attached to this Record of Decision ("ROD").
IV. SCOPE AND ROLE OF THE RESPONSE ACTION WITHIN SITE STRATEGY
The National Contingency Plan ("NCP") (40 C.F.R. S 300.430(a)(1)
(i)) states that the general goal of the remedy selection process
is to select remedies that: 1) are protective of human health and
the environment; 2) maintain protection over time; and 3)
minimize untreated waste. In addition, Section 121 of CERCLA, 42
U.S.C. § 9621, includes general goals for remedial actions at all
Superfund sites. The goals include: achieving a degree of
cleanup which assures protection of human health and the
environment (Section 121(d)(l)); selecting cost effective
remedies (Sections 121(a) and 121(b)(l)); preference for
selecting remedial actions in which treatment that permanently
and significantly reduces the volume, toxicity, or mobility of
ftR3Ql*952
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contaminants is a principal element (Section I21(b)); and
requiring that the selected remedy comply with or attain the
level of any applicable or relevant and appropriate requirements
("ARARs") of federal or State environmental laws (Section
I21(d)(2)(A)).
The primary objectives of the remedy for the Revere Chemical
Site, in addition to those stated above, are to prevent potential
exposure to the contaminated media at the Site, to control and/or
prevent the migration of contamination from the Site via wind,
and surface water transport, and to reduce residual risk to
acceptable levels. This is not the only response action planned
for this Site. As a result of comments received from the U.S.
Department of Interior, EPA has been made aware that further
verification sampling of the stream corridor is necessary in
order to evaluate the extent of stream corridor contamination
related to mercury. This additional data gathering and
subsequent evaluation of technologies for addressing stream
corridor contamination will be conducted in another phase of the
RI/FS. In addition, EPA is deferring the selection of a ground
water remedy until additional ground water data is collected.
The goal of the additional hydrogeologic investigation is to
provide information on the practicability of actively pumping
ground water to achieve background cleanup levels.
The Site-specific remedial response objectives, which take into
consideration the level of contamination and the risks posed by
the contamination, are as follows:
•Protection of human health and the environment.
•Source control of Site soils contaminated with hazardous
constituents to prevent exposure through direct contact and to
prevent leaching to ground water.
•Preventing migration of contaminants from the Site via
wind, and surface water transport.
•Protection of surface water and sediment for current and
future use, and protection of environmental receptors.
V. SUMMARY 07 SITE CHARACTERISTICS AND EXTENT OF CONTAMINATION
The recent environmental conditions at the Site have been
characterized through implementation of the Phase I RI. The
results of the Phase I RI are detailed in a Phase I Report
prepared by Dames & Moore on behalf of the Revere Steering
Committee dated March 14, 1990. The Phase I RI characterized
Site soil, ground water, surface water and stream sediments
through a series of sampling and analysis. Soil samples were
collected during the Phase I RI from a series of test trench
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excavations in areas of environmental concern. The Rl also
evaluated the quality of ground water in the overburden near
monitoring well MW-4. The results of these investigations are
included in the Phase IA RI report dated July 23, 1990. The
results of the Phase I and IA RI indicated that a Phase II
investigation was necessary to further delineate the
hydrogeologic conditions. The Phase II RI analyzed Site soil,
ground water, surface water, stream sediments, and the onsite
septic tank, and aboveground storage tanks.
The results of the soil investigation identified ten metals:
antimony, arsenic, beryllium, cadmium, chromium, copper, lead,
mercury, vanadium and zinc; all of which are present in Site .
soils at concentrations distinguishable from background.
Metals concentrations were generally greater in the interval A or
shallow (0-1 foot) soil sampled rather than the interval B or
deeper (2 feet to bedrock) soil sampled.
A metals partitioning study was conducted as part of the Phase II
RI to assess the potential for metals present in soil at the Site
to migrate to ground water as a result of rainfall infiltration.
The results of the study and scientific model predict that the
metals in the soil will not adversely impact ground water quality
above maximum contaminant levels ("MCLs").
Organic compounds detected in the soil included polycyclic
aromatic hydrocarbons ("PAHs") and phthalates. The greatest
concentration of Volatile Organic Compounds ("VOCs") in the soil
is limited to the former process and storage lagoons, the former
collection basins, an area south of the former process lagoons,
and the Process Refuse Area. VOCs and Base Neutral Extractables
("B/Ns") were also detected in the East Spray field and South
Spray field. Ninety percent of the South Spray field, an area of
approximately 8 acres, has been revegetated. The East Spray
field has an area of approximately 11 acres, mostly vegetated,
with the exception of about 20% of the total area.
Polychlorinated biphenyls ("PCBs") were detected at low
concentrations (less than 8.6 mg/kg) in very limited areas of the
process area. PCBs were not detected in any soil sample from the
spray fields.
Summary concentrations of contaminants detected in the interval A
soil samples (0-1 foot of soil) in the process area, the South
Spray field, and the East Spray field are listed in Tables 1, 2
and 3. Complete analytical results are contained within the RI
Report and the Administrative Record.
Geology
The area surrounding the Site is underlain by various members of
the Triassic-age Newark Group. The Lockatong Formation which
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underlies -the Site is fairly homogeneous. It is composed of
black to dark-gray, thickly-bedded argillites, with local
occurrences of thin-bedded black shales. The Lockatong and
Brunswick Formations are interbedded in the Site vicinity. The
Brunswick Formation ranges in composition from a thick-bedded,
resistant red to dark-gray argillite to a thin-bedded, fissile,
red shale, and siltstones. Fractures within the Lockatong and
Brunswick Formations are found along bedding planes and as joints
cutting across beds. The degree of fracturing is dependent on
the thickness and brittleness of the beds. Bedrock is at ground
surface to a depth of approximately 15 feet below ground surface.
Soil Characteristics
The predominant soil types at the Revere Chemical Site are the
Abbottstown Series, Alluvial Land, Bowmansville Series, Lansdale
Series, and Urban Land.
The Abbottstown Series consists of deep, nearly level to sloping
soils on uplands. They are formed at the base of slopes, on side
slopes, and on broad ridge tops in loamy material weathered from
red and brown shale and sandstone.
Alluvial land appears on the floodplains of small streams.
Moderate stands of moisture tolerant trees occur in some areas of
Alluvial land.
Bowmansville Series consists of deep, poorly drained, nearly
level soils on floodplains. The Bowmansville Series forms along
small, meandering streams in loamy alluvium that washed from
upland soils underlain by shale and sandstone.
Lansdale Series consists of deep, well-drained, soils on uplands.
These soils occur on side slopes and ridges, and form loamy
material weathered chiefly from brown and yellow-brown shale and
sandstone.
Most areas of Urban Land have been graded, and the original soil
material and structure have been disturbed, filled over, or
otherwise destroyed. Urban land appears in highly developed
areas of Bucks County.
Hydroaeoloav
The primary porosity and associated permeabilities of the
Lockatong and Brunswick Formations are very low. However, the
development of fractures in the bedrock can increase permeability
through secondary porosity. The Lockatong Formation is utilized
as an aquifer for residential and commercial purposes throughout
Bucks County, including the Site vicinity.
The capacity of the Lockatong Formation to store and transmit
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water is very low. Yields of 31 wells within a 1/2 mile of the
Site ranged from 5 to 90 gallons per minute ("gpm") with an
average yield of 17 gpm. Greenman (1955) reported the yields for
43 wells that tap the Lockatong Formation. Yields for these
wells ranged from 2 gpm to 25 gpm, with an average yield of 10
gpm.
Surface Drainage
The Site is primarily drained by the east and west tributaries to
Rapp Creek. The tributaries converge in the southeast portion of
the Site and discharge to Rapp Creek approximately 300 feet
beyond the Site boundary. Rapp Creek flows into Tinicum Creek,
which in turn empties.into the Delaware River. The Delaware
River is approximately four miles from the Site.
Ground water Investigation
The hydraulic conductivity of the bedrock aquifer at the Site is
primarily controlled by fractures and is relatively low.
Ground water flows from the northwest corner of the Site,
downslope to the unnamed tributaries. Shallow ground water from
the south and east portions of the Site (spray fields) also flows
toward the onsite tributaries. Shallow ground water from the
northwest corner and the south and east portions of the Site
converges at the tributaries and discharges to the creek. Deeper
ground water may flow beneath the creek.
Shallow and deep ground water flowing beneath the Site are
separated by a series of black unfractured shale beds. These
beds occur at around 100 feet below ground surface and cause the
ground water flow to behave as two systems. Ground water in the
deeper flow system is not affected by the presence of the
tributaries. Flow in the deeper system is to the southeast.
(See Figure 3)
There are eleven on-site monitoring wells. Based on the effect
of well modification during Phase II, unfiltered ground water
data collected during Phase II is not considered representative
of Site ground water quality with regard to metals
concentrations. Therefore, this data was not used for risk
assessment purposes and is not reported below. However, the RI
Report and the Administrative Record contain all of this
analytical data.
Trichloroethylene ("TCE") was detected in the following shallow
monitoring wells during the four quarterly ground water sampling
events: MW-4, MW-2, MW-7 and MW-12. The greatest TCE
concentrations were detected in samples collected from MW-4.
Concentrations in MW-4 ranged from 44 ug/1 to 170 ug/1. Each of
these monitoring wells is situated downgradient of areas where
the greatest VOC concentrations were detected in soil. These
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wells were all completed at a depth above the unfractured black
shales.
The B/N compound, 1,2,4-trichlorobenzene ("TCB"), was detected in
only MW-4 at concentrations ranging from 41 ug/1 to 150 ug/1. 1,
2- dichlorobenzene was detected in only MW-4 at concentrations
ranging from 3 ug/1 to 5 ug/1.
TCE and TCB concentrations in ground water at the Site appear to
be limited to the northwest portion of the process area. Neither
TCE nor TCB were detected in any of the four quarterly ground
water samples collected during the Phase II RI from monitoring
wells MW-ll, MW-5 & MW-10. These wells were all completed at a
depth below the black shales.
Bis(2-ethylhexyl)phthalate ("BEHP") was detected in the following
wells: MW-2, MW-5, MW-8, MW-10, MW-ll, and MW-12 at
concentrations ranging from 3 ppb to 42 ppb.
Infrequent detection of the organic compounds acetone, methylene
chloride, and carbon disulfide in the monitoring wells sampled
does not indicate that the Site is a source of these compounds.
The detected organic compounds acetone and methylene chloride are
common laboratory contaminants and/or were detected in blank
samples (i.e., control samples used to determine if contaminants
are originating from sources, e.g., laboratory other than the
sampled media).
No pesticides, PCBs, or acid extractable organic compounds
("AEs") were detected in any of the onsite ground water samples.
TCE and 1,1,1-trichloroethane (H1,1,1-TCA") were detected in one
offsite residential well south of the Site during round one
ground water sampling at estimated concentrations of 2 ug/1 and 3
ug/1, respectively. These concentrations are below federal Safe
Drinking Water Act ("SDWA") maximum contaminant levels ("MCLs")
for TCE (5 ug/1) and 1,1,1-TCA (200 ug/1). TCE was also detected
in round four ground water samples collected from an offsite
residential well north of the Site at 0.397 ug/1 and at an
offsite residential well west of the Site on the south side of
Route 611 at a concentration of 0.422 ug/1. Each of these
concentrations is less than the MCL for TCE.
Although trace amounts of TCE were detected offsite, ground water
elevation data obtained for residential wells in the Site
vicinity and the results of a ground water elevation study
conducted in the Site vicinity by the United States Geological
Survey ("USGS") indicate that the Site is hydraulically
downgradient of the residential wells that were subject *-.o ground
water sampling and analyses during the Phase II RI. Therefore,
it is concluded that constituent concentrations detected in
residential well water samples are not attributed to the Site.
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With the exception of lead that was detected in the filtered
ground water sample collected from an offsite residential well
north of the Site during round one sampling, none of the metals
or hexavalent chromium concentrations detected exceed MCLs .in
either the round one or round four filtered ground water samples
collected from the residential wells.
Lead was detected in filtered ground water samples ranging from
.75 ug/1 to 18.10 ug/1. The highest filtered sample detection
occurred in MW-5 in round one only. The proposed MCL is 15 ug/1.
The analytical detections of lead in the filtered ground water
samples were anomalous in that for each round of sampling the
detection of lead occurred in a different monitoring well.
Arsenic was detected in ground water in concentrations ranging
from 9 ug/1 to 46.6 ug/1. The MCL for arsenic is 50 ug/1.
No VOCs, Aes, B/Ns, or PCBs were detected in the Cotner ground
water sample collected during round one. Lead was detected at a
concentration that exceeded the MCL in the unfiltered ground
water sample collected from the Cotner well during round one. No
metals were detected above MCLs in the filtered samples.
Surface Water and Sediment
Several of the organic constituents detected in surface water and
sediment exceeded levels detected in background samples. Copper,
chromium and mercury were detected in tributary sediment. Copper
and manganese were detected in surface water samples at
concentrations that exceed their corresponding background level.
Mercury was not detected in background sediment samples. The
aquatic community survey indicated that the benthic community in
the east and west tributaries at the Site adjacent to the process
area had been adversely impacted. There is a rebound in the
benthic community as distance from the process area increases.
Table 14 is a comparison of inorganic analytical results of
surface water samples to background surface samples. Table 15 is
a comparison of inorganic analytical results of sediment samples
to background sediment samples. Figure 4 shows the location of
the surface water and sediments samples. Table 16 is a
comparison of the analytical results for surface water toxicity
samples to Pennsylvania Water Quality Criteria for where the
criteria were exceeded.
Solid Waste
As a result of the extensive excavations performed, it is
unlikely that additional drums remain beneath the Site in the
areas of magnetic anomalies investigated, with the exception of
the vicinity of the former Storage Lagoon C. Poor field
conditions and the thickness (up to 15 feet) of the overburden
had precluded further investigation and removal during the Phase
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11
II RI field work.
There are two solid waste refuse piles in the process area that
include household appliances, trash, abandoned automobiles, wood
and scrap metal. See Figure 5 for location.
Process Building and Septic Tank/Dry Well Investigations
Chrysotile asbestos was detected in samples collected from the
corrugated material covering the process building, the shingle
pile, and the white material covering aboveground storage tank
("AST") l.
There are three ASTs inside the process building and a dust
collector. None of the ASTs or the dust collector contained
liquids. The solid material collected from AST 1, AST 3, and AST
4 contained VOCs, B/Ns, TAL metals, and cyanide. The solid
material collected from AST 1 also contained Aes and PCBs.
The liquid sample collected from the septic tank contained VOCs.
Metals were detected in the liquid samples collected from the
septic tank and dry well. VOCs, B/Ns, and metals were detected
in the solid sample collected from the septic tank.
VI. SUMMARY OP SITE RISKS
An assessment of the potential risks posed to human health and
the environment was completed in accordance with the NCP [40
C.F.R. 300.430(d)]. This section of the ROD discusses the
results of the baseline risk assessment. The results of the
baseline risk assessment are used to determine whether
remediation is necessary, to help provide justification for
performing the remedial action and to assist in determining what
exposure pathways need to be remediated.
A. HUMAN HEALTH RISK EVALUATION
The potential human health risks posed by a Superfund Site if no
remedial action is taken are calculated in a baseline risk
assessment.
In general, a Site poses a potential human health risk if 1) the
contaminants at the Site may cause cancer or some other health
effect at existing levels, 2) there is a route or pathway through
which a receptor may be exposed, e.g., ingestion of contaminated
soil, and 3) there is a receptor which is exposed, e.g., a child
ingesting soil. In a baseline human health risk assessment, the
contaminants are evaluated, the exposure routes are characterized
and the receptors are identified.
The Site is not currently occupied. Persons potentially at risk
include offsite residents, trespassers, future onsite workers and
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future residents.
Exposure Assessment
Current land use in the vicinity of the Site is residential,
commercial and agricultural. Current onsite land use is
industrial based on current zoning. Future onsite land use is
assumed to be residential for risk assessment purposes. Ground
water beneath the Site is classified as a Class IIA aquifer, a
current source of drinking water. Numerous residential wells in
the area of the Site are used for drinking water and other
domestic uses.
•L ••
The exposure assessment identified potential exposure pathways.
Four exposure scenarios were examined under current and future
land use assumptions. Exposure of receptors to chemicals in
potentially impacted media (surface soil, ground water, and air)
were examined under Reasonable Maximum Exposure ("RME")
assumptions. For purposes of the risk assessment, the Site was
subdivided into three major areas for evaluating the surface soil
data:
•The Process Area
•The East Spray field
•The South Spray field.
Samples were grouped in these three areas for purposes of
calculating summary statistics (mean and upper confidence
limits). These groupings correspond to the subdivision of the
Site during the RI and allow an estimation of risks based on the
reported uses of different areas of the Site. The scenarios were:
1) onsite trespasser - Process area, East Spray field, and South
Spray field; 2) offsite residents under the current land use
assumption; and 3) onsite resident under the future land use
assumption. EPA performed additional calculations to evaluate
the risk posed to a future onsite worker. The analytical results
for samples collected from monitoring wells were used in the
future land use exposure scenarios.
Use of an exposure scenario based on future residential use is
consistent with EPA Risk Assessment Guidance which requires
consideration of hypothetical residential use. The NCP requires
that ground water which is suitable for use as a water supply be
protected and restored to its beneficial use.
Potential exposure pathways considered for the purpose of
evaluating Site risks included: ingestion, dermal contact and
vapor inhalation of contaminated ground water; inhalation of
volatiles and particulates in air; and ingestion and dermal
contact with surface soil. The potential exposure pathways for
current and future land use scenarios are presented in Tables 4
and 5.
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The next step in the exposure assessment process involved the
quantification of the magnitude, frequency, and duration of
exposure for the populations and exposure routes selected for
evaluation. The contaminant intake equations and intake
parameters were derived from standard literature equations and
data from EPA guidance documents. Average Daily Doses ("ADD")
and Lifetime Average Daily Doses ("LADD") were estimated for
contaminants of concern in the baseline risk assessment.
Toxicitv Assessment
The Reference Dose ("Rf D") for a substance represents the level
of intake which is -unlikely to result in adverse non-carcinogenic
health effects in individuals exposed for a chronic period of
time. For carcinogens, the slope factor is used to estimate an
upper-bound probability of an individual developing cancer as a
result of exposure to a particular level of a potential
carcinogen.
Risk Characterization
The baseline risk assessment in the RI/FS quantified the
potential carcinogenic and non-carcinogenic risks to human health
posed by contaminants of concern in several exposure media. The
carcinogenic and non-carcinogenic risks were determined for soil,
air and ground water.
Carcinogenic risk is presented as the incremental probability of
an individual contracting some form of cancer over a lifetime as
the result of exposure to the carcinogen. Risk standards for
non-carcinogenic compounds are established at acceptable levels
and criteria considered protective of human populations from the
possible adverse effect from human exposure. The ratio of the
ADD to the RfD values, defined as the hazard quotient, provides
an indication of the potential for systemic toxicity to occur.
If the sum of the aggregate hazard quotients does not exceed one,
there is not a concern for a non-carcinogenic public health
threat. The carcinogenic risks for each of the exposed
populations are summarized in Tables 6, 7, 8 and 9. The non-
carcinogenic risks are summarized on Tables 10, 11, 12, and 13.
Tables are not included for future onsite worker risks. The risk
evaluation of the Site indicated the following:
Because the hazard quotients exceeded 1 and the baseline
carcinogenic risk exceeds the risk range of 10~4 to 10~ ,
remedial action will be taken at this Site.
The principal risk analysis results for the Revere Site are
summarized below. • The exposure pathways providing the greatest
contribution to estimated health risks were soil ingestion and
dermal contact with soil.
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Current Land Use
The excess lifetime cancer risk for offsite residents currently
exposed to contaminants in soil via inhalation of dust is 2 x
10~6 (or 2 in 1,000,000).
The excess lifetime cancer risk for a Site trespasser in the
Process area is 2 x 10~6 (or 2 in 1,000,000). The exposure
pathways assumed are soil ingestion, and dermal contact with soil
and inhalation.
The excess lifetime cancer risk for a Site trespasser in the East
Spray field is 2 x 10~8 (or 2 in 100,000,000). The exposure
pathways assumed are soil ingestion and inhalation.
The excess lif-time cancer risk for a Site trespasser in the
South Spray field is 2 x 10~8 (or 2 in 100,000,000). The
exposure pathways assumed are soil ingestion and inhalation.
The hazard quotient calculated for each exposure scenario is
greater than 1.0 for estimated lifetime non-cancer effects. The
highest hazard quotients are associated with the inhalation of
chromium.
Future Land Use
The excess lifetime cancer risk for a future onsite resident is 2
x 10~4 (or 2 in 10,000). The exposure pathways include soils
ingestion, dermal contact with soil, ingestion of ground water,
dermal contact with ground water, inhalation of VOCs from ground
water, and ingestion of garden fruits and vegetables from an
onsite garden.
The excess lifetime cancer risk for a future onsite worker is 7 x
10~6 (or 7 in 1,000,000). The exposure pathways assumed are soil
ingestion and inhalation.
The hazard quotient calculated for each exposure scenario is
greater than 1.0 for estimated lifetime non-cancer effects. The
highest hazard quotients are associated with the inhalation of
chromium in dust and the ingestion of copper through consumption
of garden fruits and vegetables grown in contaminated soil.
The hazard quotient for chromium exceeds 1.0 for inhalation
exposures associated with all scenarios. The concentration of
chromium in soil was measured as total chromium. Exposures to
chromium were evaluated using a reference dose based on
hexavalent chromium, the most toxic species. Therefore, it is
likely that risks associated with inhalation of chromiuir have
been overestimated.
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Risk •
Based upon consultation with State and Federal agencies
knowledgeable about threatened or endangered species in the
Commonwealth of Pennsylvania, EPA has determined that endangered
species or sensitive habitats are near the Site. The endangered
floral species Tomanthra auriculata (false foxglove) was
identified in the South Spray field. Two types of wetlands,
Riverine and Pa lustrine, have been identified at the Site.
Riverine wetlands are limited to the east and west tributaries.
Palustrine wetlands, including open water, emergent, scrub-shrub
and forested wetlands are found in the northeast corner of the
Site or in the South Spray field.
The contaminant of most concern for environmental risk is
mercury. The northernmost contamination zone within the 2ast
Spray field contains up to 6.5 ppm, and soils in the southernmost
area contain 30 ppm. The South Spray field also contains
extensive areas of mercury contamination throughout the
delineated wetland areas and near the eared false foxglove
plants, at concentrations ranging up to 2.5 ppm. These
concentrations represent significant contamination compared to
the background soils collected, which contained no mercury
(detection limit 0.1 ppm).
Because of the proximity of the wetland areas to the contaminated
areas of the South Spray field, the environmental risk associated
with these levels of mercury in soils is expected to be of
concern. Mercury contamination of soils could provide a
significant food chain pathway to migratory birds due to feeding
on earthworms exposed to soils containing mercury.
In assessing environmental risk, EPA did not rely solely on the
conclusions of the RI report because the Agency believes the
technical conclusions of the RI were limited in scope. Further
the "weight-of-evidence" on mercury toxicity from the literature
was not considered in the RI and is necessary to evaluate
environmental risks. In particular, EPA has relied upon
information in the Administrative Record from the scientific
community (see "Mercury hazards to fish, wildlife and
invertebrates: a synoptic review" by R. Eisler and "Accumulation
of methylmercury in the earthworm, Eisenia foetida, and its
effect on regeneration" by W.N. Beyer, E. Cromartie and G.B.
Moment) , as well as upon information from the U.S. Department of
Interior ("DOI") . DOI recommends a cleanup standard of 0.1 ppm
based on no mercury detected in background samples.
Actual or threatened releases of hazardous substances from this
Site, if not addressed by the preferred alternative or one of the
other remedial measures considered, present a current or
potential threat to public health, welfare, and the environment.
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VII. DESCRIPTION OF REMEDIAL ACTION ALTERNATIVES
In accordance with Section 300.430 of the National Oil and
Hazardous Substances Pollution Contingency Plan ("NCP"), 40 CFR
300.430, a list of remedial response actions and representative
technologies was identified and screened to determine whether
they would meet the remedial action objectives at the Site.
EPA seeks to eliminate, reduce, or control risks to human health
and the environment. EPA expects to include both treatment to
minimize the threat posed by highly mobile wastes and containment
to control low-level threats. EPA expects to use treatment to
address the principal threats posed by a site, wherever,
practicable. Principal threats for which treatment is most
likely to be appropriate include liquids, areas contaminated with
high concentrations of toxic compounds, and highly mobile
materials. The principal threat at the Site is the VOC-
contaminated soils. Using the MCL for TCE in conjunction with
its partitioning properties and modeling conducted during the RI,
Organic Hot Spots are defined for VOCs as areas where the
concentration of VOCs in the soils exceeds 22.8 mg/kg.
Section 121(d) of CERCLA requires that remedial actions at CERCLA
Sites attain legally applicable or relevant and appropriate
federal and State standards, requirements, criteria and
limitations which are collectively referred to as "ARARs", unless
such ARARs are waived under CERCLA Section 121(d)(4). Applicable
requirements are those substantive .environmental protection
requirements, criteria, or limitations promulgated under federal
or State law that specifically address hazardous substances found
at the Site, the remedial action to be implemented at the Site,
the location of the Site, or other circumstances present at the
Site. Relevant and appropriate requirements are those
substantive environmental protection requirements, criteria or
limitations promulgated under federal or State law which are not
applicable to the hazardous materials found at the Site, however,
the Site problems are sufficiently similar such that their use is
well-suited to the Site. ARARs may relate to the substances
addressed by the remedial action (chemical-specific), to the
location of the Site (location-specific), or to the manner in
which the remedial action is implemented (action-specific). The
Feasibility Study ("FS"), dated July 1993, discusses the
alternatives evaluated for the Site and provides supporting
information leading to alternative selection by EPA.
It should be noted that all cost, time frames and waste/treatment
volumes indicated below are estimates based on the RI/FS and the
Administrative Record for this Site. This information will be
further refined for the selected remedial alternatives during the
remedial design.
Nine remedial alternatives were identified as possible response
actions for the Site soil and solid waste. Table 17 lists the
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remedial alternatives and provides information on estimated
costs.
The ARARs listed below are common to Alternatives S2 through S9.
Alternative SI is a no action alternative, therefore there are no
ARARs.
Offsite treatment, storage, and disposal of hazardous substances
will comply with RCRA regulations and standards for owners and
operators of hazardous waste treatment, storage, and disposal
facilities, in accordance, with 25 PA Code Chapter 264,
Subchapters A-E, Subchapter I (containers), and Subchapter J
(tanks).
RCRA regulations for the generation and transportation of
hazardous wastes (25 PA Code Chapter 262, Subchapters A, B and C,
and Chapter 263) and the Department of Transportation Rules for
Hazardous Materials Transport (49 C.F.R. Parts 107 and 171-179)
are applicable to the offsite disposal of drums and solid waste.
The Endangered Species Act of 1973, 16 U.S.C. S1651 et seq.. may
be applicable if a determination is made that endangered species
will be affected by Site remediation.
The following Residual Waste Regulations are relevant and
appropriate for all alternatives which include capping:
Standards for cap, final cover and grading: 25 PA Code
§§ 288.234, 288.436, and Appendix A Table II; Standards for
revegetation: 25 Pa Code SS 288.236 and 288.237; Standards for
water quality protection: 25 PA Code SS 288.241 and 288.244;
Standards for ground water monitoring: 25 Pa Code SS 288.251,
288.254, and 288.257.
Regulations for onsite handling and removal of asbestos at 40 CFR
Part 61, Subpart M SS 61.141, 61.145, 61.149(c) & 61.156 are
applicable to Alternatives S2 through S9.
The Toxic Substances Control Act ("TSCA") of 1976, 15 U.S.C.
§S 2601 to 2671, establishes regulations at 40 C.F.R. Part
761.60, Disposal Requirements; 761.65, Storage for Disposal;
761.207, General Manifest Requirements.
Implementation of dust controls and erosion and sedimentation
controls during capping and regrading will comply with PADER's
Chapter 102 regulations as explained in the EROSION AND SEDIMENT
POLLUTION CONTROL PROGRAM MANUAL dat*»d April 1990 (as authorized
under the Clean Streams Law, 35 P.S. S 691.202 et. sea.)
Fugitive dust emissions generated during remedial activities will
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be controlled in order to comply with fugitive dust regulations
in the federally-approved State Implementation Plan for the
Commonwealth of Pennsylvania, 25 PA Code SS 123.1 - 123.2, and
will not violate the National Ambient Air quality Standards for
particulate matter, 40 C.F.R. §§ 50.6 and 25 PA Code SS 131.1
through 131.4.
The ARARs listed below are common to Alternatives S3, S6, S7, S8
and S9.
National Primary and Secondary Ambient Air Quality requirements,
40 C.F.R. 50 et sea.. are applicable and must be met for the
discharge of contaminants into the air. Pennsylvania's Air
Pollution Control, ScJ: is also applicable, as are Pennsylvania's
Air Pollution Control Regulations at 25 Pa. Code SS 121.1, 121.2,
121.7. 121.8 - General Provisions, Part 123 - Standards for
Contaminants; and 127.1, 127.11. 127.12(a)(5) •;• Construction,
Modification, Reactivation and Operation of Sources.
The requirements of Subpart AA (Air Emission Standards for
Process Vents) of the Federal RCRA regulations set forth at 40
CFR Part 264, Subpart AA are relevant and appropriate depending
on the level of organics in the contaminated soil. These
regulations require that total organic emissions from the air
stripping process vents must be less than 1.4 kg/hr (3 Ib/hr) and
2800 kg/yr (3.1 tons/yr).
25 Pa. Code § 123.31 prohibits the emission of malodorous
contaminants from crossing the property line.
25 Pa. Code S 127.11 will apply. These Commonwealth of
Pennsylvania regulations require a plan for approval for most air
stripping and soil venting/decontamination projects designed to
remove volatile contaminants from soil, water, and other
materials regardless of emission rate.
25 Pa. Code S 127.12(a)(5) will apply to new point source air
emissions that result from implementation of the remedial
alternatives listed above. These Commonwealth of Pennsylvania
regulations require that emissions be reduced to the minimum
obtainable levels through the use of best available technology
("BAT") as defined in 25 PA. Code S 121.1.
ALTERNATIVE 81: MO ACTION/INSTITUTIONAL CONTROLS
Estimated Capital Cost: $0
Estimated Annual O&H Costs: $132,915
Estimated Present Worth: $2,176,144
Estimated Construction Time: none
The NCP requires that EPA consider a "No Action" alternative for
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each site to establish a baseline for comparison to alternatives
that do require action. For the Revere Site, this alternative
provides only for maintaining the current conditions at the Site
and routine monitoring activities in order to provide information
on changes in Site conditions. The use of institutional controls
would not require modifications but, would limit access to the
Site through the use of fencing and deed restrictions. Long-term
monitoring and a five-year review program would be required.
There are no ARARs associated with a Mo Action Alternative.
ALTERNATIVE 82: EROSION CONTROL CAP/OF*SITE SOLID WASTE DISPOSAL
Estimated Capitaj. Cost: $3,769,656
Estimated Annual O&M Costs: $161,655
Estimated Present Worth: $6,254,843
Estimated Construction Time: 12 months
Under this alternative, the solid waste refuse piles in the
Process area which include household appliances, trash, abandoned
automobiles, wood, and scrap metal and the contents of the
aboveground storage tanks (See Figure 5) would be sampled and
analyzed for waste characterization and disposed offsite at an
EPA-approved facility. Buried drums may still exist in the
vicinity of former Storage Lagoon C (Figure 2). Any buried drums
would be excavated, characterized,.and transported to an EPA-
approved facility for disposal.
The asbestos would be removed from the sides of the Process
Building by a licensed asbestos remediation contractor.
Asbestos-containing material ("ACM") surrounding one of the
aboveground storage tanks inside the Process Building and the
shingle debris pile adjacent to the Process Building would also
be removed by a licensed asbestos remediation contractor. The
contents, if any, of the Process Building's aboveground tanks
would be removed, packaged, sampled, and analyzed. Based on the
results of the analysis, this material would be properly disposed
offsite at an EPA approved facility.
Following removal of the solid wastes, all areas in the process
area and the spray fields where soils exceed any of the following
criteria would be covered with an erosion control cap: the hazard
index for exposure to contaminated soils exceeds 1; exposure to
contaminated soils represents a carcinogenic risk greater than 1
x 10~4; and the soils contain leachable contaminants that will
leach to levels above the method detection limits for those
contaminants using Drinking Water Analytical methods as described
in Tables 18 and 19. Subgrade preparation would be completed by
grading the Site to control surface water run-on and run-off
thereby controlling erosion. Common fill, at least 12 inches
thick, would be placed over the area to be capped and covered
AR3Ql*967
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with 6 inches of top soil. Drainage swales would be lined where
necessary to prevent washout. Institutional controls such as
fencing and deed restrictions would be used to limit access to
the Site.
Solid waste disposal can be accomplished within approximately
nine months after the approval of the alternative. The erosion
control cap can be completed within 12 months of the initiation
of construction activities. Approximately 12 to 18 months would
be required to establish vegetation on the cap. Long-term
monitoring and a five year-review program would be required.
The ARARs listed as common ARARs are applicable to this
Alternative. This alternative will meet all common ARARs
described except the Standards for Cap under the landfill closure
requirements of the Pennsylvania Residual Waste Regulations.
ALTERNATIVE S3: EROSION CONTROL CAP/CLAY CAP-SLURRY WALL/VACUUM
EZTRACTION/OFFSITE SOLID WASTE DISPOSAL
Estimated Capital Cost: $5,240,466
Estimated Annual O&M Costs: $161,655- 944,038
Estimated Present Worth: $9,122,139
Estimated Construction Time: 21 months
This alternative includes the removal and offsite disposal of the
solid waste as described in Alternative S2. After removal of the
solid waste from the Site, a slurry cutoff wall will be installed
around Collection Basins AA and BB, where concentrations of TCB
are defined as a TCB Hot Spot. A TCB Hot Spot is an area where
the soil concentration of TCB exceeds 4,437 mg/kg. The slurry
cutoff wall will isolate the TCB Hot Spot areas of the Site soil
containing TCB which may potentially come into contact with
horizontally migrating ground water. Following installation of
the slurry cutoff wall, Collection Basins AA and BB will be
covered with a clay cap (See Alternative S4 for a description of
a clay cap). Following the removal of the solid waste, all areas
in the Process Area and the Spray fields where the concentration
of contaminants exceed any of the following criteria will be
covered with an erosion control cap as described in Alternative
S2: the hazard index for exposure to contaminated soils exceeds
1; exposure to contaminated soils represents a carcinogenic risk
greater than 1 x 10~4; the soils contain leachable contaminants
that will leach to levels above the method detection limits for
those contaminants using Drinking Water Analytical methods as
described in Tables 18 and 19. Additionally, vacuum extraction
("VE") systems would be installed in the areas of the Site where
the concentration of total VOCs in soil exceeds 22.8 mg/kg.
Under this alternative, VE wells would be installed below grade
in the areas of concern. The organic constituents in the
subsurface will volatilize and be drawn to the extraction wells
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because of the induced vacuum. The vapor discharge from the VE
system would pass through an off-gas treatment unit, such as
vapor-phase 6AC or a thermal treatment unit, to reduce
contaminant concentrations in the air stream to acceptable.levels
prior to discharge. When the VE systems are removed from the
Site, any intrusions into capped areas will be repaired.
Solid waste disposal can be accomplished within approximately
nine months. Clay cap and slurry cutoff wall installation can be
completed within 3 months, and the erosion control cap can be
completed within approximately twelve months of the initiation of
construction activities. Approximately 12 to 18 months would be
required to establish vegetation of the cap. Institutional
controls such as fencing and deed restrictions would be used to
limit access to the Site; long-term monitoring and a five-year
review program would be required.
The ARARs listed as common ARARs are applicable to this
Alternative. This alternative will meet all common ARARs
described except the Standards for Cap under the landfill closure
requirements of the Pennsylvania Residual Waste Regulations.
ALTERNATIVE 84: CLAY CAP/SLURRY WALL/OFF8ITB SOLID WASTE
DISPOSAL
Estimated Capital Cost: $7,780,510
Estimated Annual O&M Costs: $161,655
Estimated Present Worth: $10,265,697
Estimated Construction Time: 15 months
This alternative includes the removal and offsite disposal of the
solid waste as described in Alternative S2. After removal of the
solid waste from the Site, a slurry cutoff wall will be installed
around Collection Basins AA and BB as described in Alternative
S3. Following installation of the slurry cutoff wall, the
process area and isolated areas in the spray fields would be
covered with a clay cap or equivalent to achieve a 10~7
permeability or less in areas that exceed the criteria set forth
in Alternative 3. Subgrade preparation would be completed by
grading the Site to control surface water run-on and run-off
thereby controlling erosion. Compacted clay would be placed over
the areas to be capped. A sand drainage layer would be placed
over the clay. The sand drainage layer would be covered with 18
inches of common fill and 6 inches of top soil.
Solid waste disposal can be accomplished within approximately
nine months. Slurry cutoff wall installation can be completed
within 3 months, and the clay cap can be completed within
approximately twelve months of the initiation of construction
activities. Approximately 12 to 18 months would be required to
establish vegetation of the cap. Institutional controls such as
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fencing and deed restrictions would be used to limit access to
the Site; long-term monitoring and a five-year review program
would be required.
The ARARs listed as common ARARs are applicable to this
Alternative. This alternative will meet all ARARs.
ALTERNATIVE 85: IMPERMEABLE CAP/SLURRY WALL/OPPSITE DISPOSAL
Estimated Capital Cost: $11,249,062
Estimated Annual O&M Costs: $167,415 - 179,395
Estimated Present Worth:, $13,834,050
Estimated Construction Time: 15 months *
This alternative includes the removal and offsite disposal of the
solid waste as described in Alternative S2. Following its
removal, a slurry cutoff wall will be installed around Collection
Basins AA and BB, where TCB concentrations are defined as an TCB
Hot Spot. A TCB Hot Spot is an area where the soil concentration
of TCB exceeds 4,437 mg/kg. Following completion of the slurry
walls, the Process Area and isolated areas in the Spray fields
would be covered with an impermeable cap in areas that exceed the
criteria set forth in Alternative S3. Subgrade preparation would
be completed by grading the Site to control surface water run-on
and run-off above the cap to the adjacent tributaries of Rapp
Creek. A geotextile filter fabric .and flexible membrane liner
would be placed over the areas to be capped and a sand drainage
layer would be installed over the geomembrane. A second membrane
would be laid on top of this drainage layer and covered by a 12-
inch coarse sand layer. This sand layer would be covered with a
geotextile fabric. Finally, the entire membrane system would be
covered with 18 inches of common fill and 6 inches of topsoil and
then vegetated.
Solid waste disposal can be accomplished within approximately
nine months. Slurry cutoff wall installation can be completed
within 3 months, and the impermeable cap can be completed within
approximately twelve months of the initiation of construction
activities. Approximately 12 to 18 months would be required to
establish vegetation of the cap. Institutional controls such as
fencing and deed restrictions would be used to limit access to
the Site; long-term monitoring and a five-year review program
would be required.
The ARARs listed above as common ARARS are applicable to this
Alternative. This alternative will meet all ARARs.
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ALTERNATIVE 86: CLAY CAP/SLURRY WALL/VACUUM BXTRACTION/OFF8ITB
DISPOSAL
Estimated Capital Cost: $8,230,671
Estimated Annual O&M Costs: $161,655 - 620,552
Estimated Present Worth: $11,152,894
Estimated Construction Time: 21 months
This alternative includes the removal and offsite disposal of
solid waste as described in Alternative S2. Following removal of
the solid waste, a slurry cutoff wall will be installed around
the areas of Collection Basins AA and BB as described in
Alternative S3 . The Process Area and certain areas of the Spray
, fields would be covered with a clay cap as described in
Alternative S4. Additionally, vacuum extraction ("VE") systems
would be installed in the areas of the Site where the
concentration of VOCs in soil exceeds 22.8 mg/kg. Under this
alternative, VE wells would be installed below grade in the areas
of concern. The organic constituents in the subsurface will
volatilize and be drawn to the extraction wells because of the
induced vacuum. The vapor discharge from the VE system would
pass through an off -gas treatment unit, such as vapor-phase GAC
or a thermal treatment unit, to reduce contaminant concentrations
in the air stream to acceptable levels prior to discharge. When
the VE systems are removed from the Site, any intrusions into
capped areas will be repaired.
Solid waste disposal can be accomplished within approximately
nine months. Slurry cutoff wall installation can be completed
within 3 months, and the clay cap can be completed within
approximately twelve months of the initiation of construction
activities. Approximately 12 to 18 months would be required to
establish vegetation of the cap. Institutional controls such as
fencing and deed restrictions would be used to limit access to
the Site; long-term monitoring and a five-year review program
would be required.
The ARARs listed above as common ARARS are applicable to this
Alternative. This alternative will meet all ARARs.
ALTERNATIVE 87: EROSION CONTROL CAP/LOW TEMPERATURE THERMAL
STRIPPINO/OFF8ITE DISPOSAL
Estimated Capital Cost: $16,252,161
Estimated Annual O&M Costs: $161,655 - 869,005
Estimated Present Worth: $20,052,584
Estimated Construction Time: 36 months
This alternative includes the offsite disposal of solid waste at
the Site as described in Alternative S2, excavation and treatment
of the process area soil that contains total VOCs above the
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preliminary cleanup level in soil of 6.1 mg/kg and/or TCB above
the preliminary cleanup level of 6,236 mg/kg by Low Temperature
Thermal Stripping ("LTTS"), offsite disposal of treated soil, and
installation of an erosion control cap as described in
Alternative S2. For this alternative 6.1 mg/kg total VOCs and
6,234 mg/kg TCB was used to estimate the volume of contaminated
soil to be treated. Actual cleanup levels are expected to be
lower, which may increase cost and estimated construction time.
The LTTS involves treating an estimated 26,000 cubic yards or
approximately 34,000 tons of contaminated soil. These estimates
are based on the preliminary cleanup levels listed in the
preceding paragraph and are subject to change. Costs are
anticipated to increase based on the cleanup levels to be
developed. Soil is fed into a dryer and heated to a temperature
of 200 to 800 degrees Fahrenheit. An inert gas is introduced to
strip the organic compounds from the soil, followed by a carbon
adsorption unit or an incinerator to recover or destroy the
organic compounds. The exhaust from the LTTS unit would contain
detectable concentrations of organic emissions and particulate
matter generated during processing operations. Each of these
would be captured using an appropriate air treatment/control
system.
Solid waste disposal can be accomplished within approximately
nine months. Based on the preliminary cleanup levels for VOCs
and TCB in soil, and an estimated throughput rate of 75 tons per
day and assuming a 6 day-a-week operation for the LTTS unit, the
approximate time required to process the soil at the Site where
organic constituents are present at concentrations that require
remediation is 2 years. Final grading and cap installation would
be performed after the completion of remedial measures and
demobilization of the LTTS unit. The erosion control cap can be
completed within approximately twelve months of the initiation of
construction activities. Approximately 12 to 18 months would be
required to establish vegetation of the cap. Institutional
controls such as fencing and deed restrictions would be used to
limit access to the Site; long-term monitoring and a five-year
review program would be required.
The ARARs listed as common ARARs are applicable to this
Alternative. This alternative will meet all common ARARs
described except the Standards for Cap under the landfill closure
requirements of the Pennsylvania Residual Waste Regulations.
ALTERNATIVE 88: LTTS/EROSION CONTROL CAP/ON8ITE DISPOSAL
Estimated Capital Cost: $12,735,975
Estimated Annual O&M Costs: $161,655 - 869,005
Estimated Present Worth: $16,536,398
Estimated Construction Time: 30 months
AR30U972
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Under this alternative an erosion control cap would be installed
as described in Alternative S2. Soil containing VOCs and TCB in
excess of the preliminary cleanup levels would be treated onsite
by LTTS as described in Alternative S7. Solid waste would oe
treated onsite as required by applicable RCRA and Pennsylvania
Solid Waste Regulations governing land disposal. Both the
treated soil and the solid waste would be disposed in a hazardous
waste landfill cell constructed onsite.
A double-lined landfill cell with a leachate collection system
and leak detection layer would be constructed to contain treated
soil and solid waste. An area of approximately 6 acres would be
required for installation of the cell.
After disposal operations are complete, the cell would be closed
in accordance with the requirements and regulations for hazardous
waste landfills promulgated by the Commonwealth of Pennsylvania.
Based on the preliminary cleanup levels for VOCs and TCB in soil,
and an estimated throughput rate of 75 tons per day and assuming
a 6 day-a-week operation for the LTTS unit, the approximate time
required to process the soil at the Site where organic
constituents are present at concentrations that require
remediation is 2 years. It is anticipated that the landfill cell
can be constructed while the soil is being thermally treated.
The entire alternative is estimated to be completed in 2 years, 6
months. Institutional controls such as fencing and deed
restrictions would be used to limit access to the Site.
The ARARs listed as common ARARs are applicable to this
Alternative. This alternative will meet all common ARARs
described except the Standards for Cap under the landfill closure
requirements of the Pennsylvania Residual Waste Regulations.
ALTERNATIVE 89: VACUUM EXTRACTION/SOIL 8TABILI2ATION/EROSION
CONTROL CAP/OFF8ITE DISPOSAL
Estimated Capital Cost: $31,320,242
Estimated Annual O&M Costs: $161,655 - 1,286,226
Estimated Present Worth: $35,863,182
Estimated Construction Time: 48 months
This alternative includes offsite disposal of solid waste; vacuum
extraction at locations in the process area where the
concentration of VOCs in soil are defined as an Organic Hot Spot,
i.e. concentration of VOCs exceeds 22.8 mg/kg; stabilization of
inorganic compounds in process area soil; installation of an
erosion control cap using the criteria set forth in Alternative
S2; and installation of a slurry cutoff wall around the area
containing TCB as described in Alternative S3. Solid waste
disposal, VE, and erosion control capping have been discussed
AR30l*973
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under Alternatives S2 and S3.
Surficial stabilization of the soil would be performed using
either a backhoe or grout injectors for introducing and mixing
the admixture in the soil. The cementitious mixture would be
prepared in a specialized mixing apparatus, and transported to
the areas undergoing stabilization. The actual time required for
complete stabilization would be determined during the pre-design
treatability studies and confirmed in the field during
implementation. After the remediated areas have been stabilized
to specifications, the erosion control cap would be installed.
Institutional controls such as fencing and deed restrictions
would be used to limit access to the Site.
Solid waste disposal can be accomplished in approximately nine
months. The estimated time to complete soil stabilization is 2
to 3 years. The erosion control cap can be completed in
approximately 12 months of initiation of construction activities.
The ARARs listed as common ARARs are applicable to this
Alternative. This alternative will meet all common ARARs
described except the Standards for Cap under the landfill closure
requirements of the Pennsylvania Residual Waste Regulations.
VIII. SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES
The remedial action Alternatives described above for each area of
the Site were evaluated under the nine evaluation criteria set
forth in the NCP at 40 C.F.R. S 300.430(e)(9). These nine
criteria are organized according the following categories listed
in 40 CFR § 300.430(f)(1):
Threshold Criteria!
•Overall protection of human health and the environment
•Compliance with applicable or relevant and appropriate
requirements (ARARs)
Primary Balancing Criteria;
•Long-term effectiveness and permanence
•Reduction of toxicity, mobility, or volume through treatment
•Short-term effectiveness
•Implementabi1ity
•Cost
Modifying Criteria;
•Community acceptance
•State acceptance
Threshold criteria must be satisfied in order for an alternative
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27
to be eligible for selection. Primary balancing criteria are
used to weigh the strengths and weaknesses of the alternatives
and to identify the alternative which provides the best balance
of the criteria, state and community acceptance are modifying
criteria which are taken into account after public comment is
received on the Proposed Plan. Descriptions of the individual
criteria follow:
Overall protection of human health and the environment;
Whether the remedy provides adequate protection and how risks
posed through each pathway are eliminated, reduced or controlled
through treatment, engineering controls, or institutional
controls. * '
Compliance with ARARs:
Whether or not a remedy will meet all applicable or relevant and
appropriate requirements ("ARAKs") of Federal and State
environmental statutes and/or whether there are grounds for
invoking a waiver. Whether or not the remedy complies with
advisories, criteria and/or guidance that may be relevant.
Long-term effectiveness and permanence;
The ability of the remedy to afford long term, effective and
permanent protection to human health and the environment along
with the degree of certainty that the alternative will prove
successful.
Reduction of toxicity. mobility or yniumes
The extent to which the alternative will reduce the toxicity,
mobility, or volume of the contaminants causing the site risks.
Short-term effectiveness;
The time until protection is achieved and the short term risk or
impact to the community, onsite workers, and the environment that
may be posed during the construction and implementation of the
alternative.
Implementabi1ity;
The technical and administrative feasibility of a remedy,
including the availability of materials and services needed to
implement that remedy.
Includes estimated capital, operation and maintenance, and net
present worth costs.
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State acceptance;
Whether the Commonwealth concurs with, opposes, or has no comment
on the Preferred Remedial Alternative.
Community acceptance;
Whether the public agrees with the Preferred Remedial
Alternative. This is assessed in the Record of Decision
following a review of the public comments received on the
Administrative Record and the Proposed Plan.
^
A. Comparative Analysis Of Alternatives
i
Overall Protection
As stated in the Summary of Site Risks section above, EPA has
defined Organic Hot Spots in soil as areas where without
treatment or containment the contaminants have the potential to
cause ground water contamination above the drinking water
regulations. SI (No Action) would neither eliminate nor reduce
to acceptable levels the threats to human health and the
environment presented by the contamination at the Site. S2
(Erosion Control Cap) would provide less than adequate protection
since no treatment would be used to reduce contaminant
concentrations in soils to levels that would not impact ground
water. Alternatives SI and S2 will not be discussed in the
remainder of this analysis.
Alternatives S3 and S6 include measures to eliminate potential
risks to human health and the environment by treating VOC
contaminated soils and by containing TCB-contaminated soils and
by disposing of solid waste present at the Site at a secure
offsite facility. Alternative S6 provides a higher degree of
protection of the environment than S3 since the cap will provide
greater reduction of infiltration through the soil column thereby
reducing potential risk to ground water.
As with Alternatives S3 and S6, Alternatives S4, S5, S7, and S9
include offsite disposal of solid waste at a secure offsite
facility. Alternative S4 will limit the infiltration of
precipitation as effectively as Alternative S6, however without
treatment of the mobile VOCs in soils, S4 is less protective than
S6. The S5 cap will provide a higher level of containment than
Alternatives S3 and S6. Alternative S5 (Impermeable cap)
provides the highest level of containment and will virtually
eliminate precipitation and infiltration through the overburden
soil column.
Alternatives S7 and S8 use LTTS to permanently reduce the
concentration of TCE and TCB in soil. These alternatives provide
the greatest level of reduction of TCB in soil through treatment
AR30i*976
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and therefore are more protective than S3, S4, S5 and S6.
Alternative S9 is the most protective in terms of controlling
potential impacts to ground water from the inorganics in soil at
the Site dependent upon the stability of the solidified matrix.
Isolation of the stabilized soil under the erosion control cap
would further reduce the potential for metals to impact ground
water than the level of protection provided only by the erosion
control cap under Alternatives S3, S7, and SB. Although the
results of the metal partitioning study conducted during the RI
indicate that metals are not significantly mobilized by
precipitation infiltration, stabilization would further reduce
•f the potential for metals to impact ground water.
-•- ... t' '.
S6 will provide effective reduction of infiltration through the
overburden soil column. The VE extraction of organic hot spots
and the use of a slurry wall to isolate the TCB from shallow
ground water will further reduce potential risks to ground water
to an acceptable level.
Compliance with ARARs
The alternatives which address soil contamination would attain
all their respective ARARs with the following exceptions.
Alternatives S3, S7, and S8, and S9 would not attain the closure
requirements for a landfill under the Pennsylvania Residual Waste
Regulations based on the permeability of the soil erosion control
cap. In addition, S3 would not comply with the siting
requirements for an onsite landfill due to the shallow depth to
bedrock at the Site.
Long-Term Effectiveness and Permanence
Capping and slurry cutoff walls are effective long-term means of
eliminating these exposure routes and resulting risks provided
that the caps are maintained. Alternative S2 provides the lowest
level of long-term effectiveness and permanence because it leaves
all the organic contaminated soils in place without treatment and
relies solely upon a soil erosion control cap. Alternative S5 is
more effective than S2 because it employs an impermeable cap to
prevent exposure but still does not employ treatment. The
impermeable cap will control infiltration to a greater degree
than either a soil or a clay cap but would not reduce the
toxicity of the contaminants. This alternative would only be
reliable to mitigate impacts to ground water above drinking water
levels if the cap is properly maintained. Alternatives S3, 86,
and S9 use VE to permanently reduce TCE concentrations in
subsurface soil to levels that will not impact ground water above
MCLs. Alternatives S3, S4, S6 and S9 employ a clay cap and
slurry cutoff wall to isolate TCB Organic Hot Spots from ground
water thereby reducing risk to ground water from TCB. Since S4
and S6 employ a clay cap over the entire process area and
selected areas of the spray fields these alternatives would have
AR3Ql*977
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31
risk posed by exposure to contaminated soils. Alternative S7 and
S8 use LTTS to control the source of organic contamination and
require greater time to implement due to excavation activities.
Alternative S9 is more complex than the other alternatives
because of the soil stabilization component. S9 requires the
longest time before risk from direct soil contact and ingestion
is controlled.
Implementability
Alternatives S2, S4, and S5 would be the easiest to implement
because no treatment of contaminated soils is involved. The
construction techniques and equipment required to install the
caps under all the capping alternatives are common and readily
available. The quantity and types of solid waste present at the
Site should not pose a problem in terms of available off"ite
disposal facility capacity. Alternatives S3, S6, S7, and SB can
be implemented fairly easily. VE and LTTS are established
technologies requiring the mobilization of process equipment to
the Site. The VE equipment is more readily available and easier
to install and operate. VE is considerably less disruptive than
LTTS and soil stabilization, therefore S6 is more easily
implamentable than S7, S8, and S9.
costs
Capital and operation and maintenance costs are summarized in
Table 17. The estimated present worth cost of the selected
alternative is $11,152,894. This figure represents the "present
worth value" of all future cost activities associated with the
selected alternative as discussed in the Feasibility Study
Report. This estimate is used for cost comparison purposes.
In summary, the preferred alternative is believed to provide the
best balance of trade-offs among the alternatives evaluated with
respect to the nine criteria above. Based on the information
available at this time, EPA believes the preferred alternative
would protect human health and the environment, would comply with
ARARs and be cost-effective. In addition, permanent disposal
options would be utilized to the maximum extent practicable.
Community Acceptance
The July 28, 1993 Proposed Plan and the August 12, 1993 public
meeting produced a number of comments from the general public and
the PRPs for the Site. Responses to these comments appear in the
Responsiveness Summary Section of this ROD.
State Acceptance
The Commonwealth of Pennsylvania has indicated concurrence with
the selection of Alternative S6 for Operable Unit One of this Site.
AR30U979
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IX. THE SELECTED REMEDY AMD PERFORMANCE STANDARDS
aedv for the og>*i*»i«tnated ac
Following review and consideration of the information in the
Administrative Record file, the requirements of CERCLA and the
NCP, and public comment, EPA has selected Alternative S6 for the
treatment, and containment of contaminated soil and disposal of
solid waste and debris. The main components of the Selected
Remedy for this Operable Unit are:
Offsite disposal of solid waste and debris
Treatment of v6ocontaminated soil by vacuum extraction
Source containment by slurry wall for TCB area
Source containment by capping
Fencing to prevent access to capped areas
Site restoration by revegetation
Deed restrictions
Long-term ground water monitoring
This selected remedy differs from the Preferred Alternative
described in the July 28, 1993 Proposed Plan in two respects; 1)
EPA is deferring the selection of a ground water remedy until
additional ground water data is gathered; 2) EPA is requiring
additional samples be taken in the stream corridor. The goal of
the additional hydrogeologic investigation is to provide
information on the practicability of actively pumping ground
water to achieve background cleanup levels, as well as to
determine the expected rate of natural attenuation of
contaminants in the aquifer after the organic hot spots have been
remediated. The goal of requiring additional sampling in the
stream bed corridor is to determine the extent of mercury
contamination and to evaluate appropriate remediation options for
the stream bed corridor.
1. Offsite disposal of solid waste and debris
A. Description of the Component of the Remedy
Under the remedy, the solid waste refuse piles 1 and 2 which
include household appliances, trash, abandoned automobiles, wood
and scrap metal (See Figure 5), and contents of the aboveground
storage tanks shall be sampled, analyzed for waste
characterization and disposed offsite at an EPA-approved
facility. All buried drums shall be excavated, characterized,
and transported and disposed at an EPA-approved disposal
facility.
The asbestos will be removed from the sides of the Process
Building by a licensed asbestos remediation contractor.
Asbestos-containing material ("ACM") surrounding one of the
AR30<*980
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aboveground storage tanks inside the Process Building and the
shingle debris pile adjacent to the Process Building will also be
removed by a licensed asbestos remediation contractor. The
contents, if any, of the Process Building aboveground tanks will
be removed and packaged, sampled, and analyzed. Based on the
results of the analysis, this material will be properly disposed
offsite at an EPA-approved facility.
B. Performance Standards
All solid waste and debris found onsite and all excavated drums
shall be removed from the Site and shall be evaluated in
accordance with RCRA identification requirements set forth at 25
PA Code Chapter 261. Onsite handling of any wastes found to .
exhibit a characteristic of a hazardous waste shall comply with
the substantive portions of the RCRA regulations that pertain to
generators and transporters of hazardous waste set forth at 25 PA
Code Chapters 262 and 263.
The removal and disposal of asbestos and asbestos containing
material shall be in accordance with the requirements of the
National Emission Standards for Hazardous Air Pollutants
("NESHAPs") set forth at 40 CFR Part 61, Subpart M and in
particular §§ 61.141(c) and 61.145.
2. Treatment of VOC-contaminated soil
A. Description of the Component of th« Remedy
This portion of the remedy consists of insitu vacuum extraction
of VOCs from all soil in the entire process area (See Figure 2)
which contains more than 22.8 mg/kg total VOC in the soil column
from surface to bedrock. The process area is approximately 25
acres and is enclosed by a fence as shown in Figure 2. The
vacuum extraction system includes a manifold system to pull air
through the soil for treatment by means of carbon adsorption.
Vacuum extraction will continue until the soil left in place
meets the performance standard below.
B. Performance Standard"
Indicator compounds for evaluation shall be chosen according to
their presence and prevalence in the initial off gas, toxicity,
and physical characteristics which would affect stripping rates.
The system shall operate until nondetect levels or no significant
removal1 levels of the determined indicator compounds have been
"no significant removal" levels will be determined by
EPA based on evaluation of concentrations of constituents in the
off gas and statistical analysis of mass of constituents
extracted per unit time, rate of decline of mass extraction, and
AR30l*98l
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demonstrated for three consecutive months and subsequent spike2
values reveal nondetect or no significant removal levels.
3. Construction of slurry vail
A. Description of the Component of the Remedy
A circumferential slurry cutoff wall will be constructed around
the former Collection Basins AA and BB as shown in Figure 2.
This vertical, physical barrier will be used to isolate the soil
areas which exceed 4,437 mg/kg of TCB in the soil.
This, in combination with the clay cap, will effectively isolate
these soils by limiting vertical infiltration as well as
horizontal migration of ground water.
B. Performance Standards
The slurry wall shall be constructed to have an in-place
permeability of no greater than 1 x 10~7 cm/sec. The trench
shall be excavated an appropriate depth into the bedrock to
prevent seepage under the wall. The slurry wall shall be tied
into the clay cap. Predesign studies shall be performed prior to
implementation to ensure contaminant compatibility with proposed
slurry wall backfill. Detailed construction specifications shall
be developed during the remedial design in accordance with EPA
guidance Slurry Trench Construction for Pollution Micrration
Control - EPA-540/2-84-001 Feb. 1984 and shall be subject to EPA
approval.
A post-construction maintenance plan shall be developed to
maintain the integrity and effectiveness of the slurry wall,
including making repairs to the wall as necessary.
4. Construction of cap
A. Description of the Component of the Remedy
As part of the remedy, a clay cap or its equivalent which
achieves a 10~7 cm/sec permeability or less ("cap") shall be
constructed in the process area and spray fields depicted in
Figure 2. The cap shall be constructed in the areas where the
soils exceed any of the following criteria: the hazard index for
exposure to contaminated soils exceeds 1; exposure to
spike concentrations.
2"Spike" values refer to the initial concentrations
displayed in off gas when the system is either started up
initially or when the system is "pulsed" (restarted after being
shut off for a period to allow the system to re-equilibrate).
AR30U982
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contaminated soils represents a carcinogenic risk greater than 1
x 10~4; or when using the Synthetic Precipitation Leaching
Procedure, listed as EPA method 1312, the soils contain leachable
contaminants that will leach to levels above the method detection
limits for those contaminants using Drinking Water Analytical
methods as described in Tables 18 and 19. These methods listed
in Tables 18 and 19 are typically used to analyze drinking water.
When using these methods to analyze the leachate, the actual
method detection limits attainable may be higher than those
listed in Tables 18 and 19.
The clay cap will prevent incidental contact with surficial soil,
eliminate fugitive dust emissions, prevent wind and water erosion
of soil from the Site and reduce both infiltration and
percolation of precipitation through the soil contamination
areas. Surface water diversion controls will be used in
conjunction with the cap to control Site runoff and to divert
overland flow of surface water away from the soil contamination
areas, thus reducing the potential for erosion of the cap.
B. Performance Standard
The cap shall be constructed to meet the performance
specifications applicable under 25 PA Code SS 288.234, 288.236,
288.436, and Appendix A. These standards require, among other
things, that the cover achieve a permeability of no more than 1 x
10~7 cm/sec. Vegetation of the final cover shall meet the
standards specified in 25 PA Code SS 288.236 and 288.237,
Standards for Revegetation. A post-construction maintenance plan
shall be developed to ensure maintenance of the integrity and
effectiveness of the final cover, including making repairs to the
cap as necessary to correct the effects of settling, subsidence,
erosion, or other events.
5. Perimeter Fencing
A. Description of the Component of the Remedy
A perimeter fence has been erected around portions of the process
area. If the existing fence must be removed during construction
activities, a replacement fence must be erected upon completion.
A chain-link fence shall be constructed around the perimeter of
the capped areas in order to prevent unauthorized access. Plans
for maintenance of the fence shall be included in a post-
construction maintenance plan.
B. Performance Standard
The chain-link fence shall have a minimum height of six feet and
shall be equipped with locking gates. The fence shall be
maintained in a manner sufficient to prevent unauthorized access
to the capped areas.
flR30i*983
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36
6. Site Restoration
A. Description of tbe Component of tbe Remedy
Site restoration shall include specific measures to promote
wildlife habitat diversity without jeopardizing the integrity of
the cap. Careful attention shall be paid to the selection of
plant species (with emphasis on use of native grasses or
vegetation indigenous to the area as well as those with food and
cover values) and planting patterns. Use of such vegetation
shall not preclude the use of annual grasses commonly used to
quickly stabilize the cap soil. These aspects will be detailed
in the remedial design. All planning activities associated with
habitat restoration shall be performed in consultation with the •
U.S. Fish and Wildlife Service ("FWS").
B. Performance Standards
Standards for revegetation set forth at 25 PA Code §§ 288.238 and
288.237 shall apply to stabilizing the Site soil with grasses
etc.
7. Deed Restrictions
Deed restrictions shall be developed and submitted to EPA for
approval. Once approved, these deed restrictions shall be placed
in the deed to the Site by filing said restrictions with the
Recorder of Deeds of the appropriate County Court. The deed
restrictions shall protect the integrity of any structure now or
hereafter built, installed, or otherwise placed on the Site for
purposes of remediation of the Site. The deed restrictions shall
also prohibit the use of ground water on the Site for as long as
contamination remains onsite. The deed restrictions shall be
valid and binding in the Township and Commonwealth in which the
Site is located. At a minimum, the deed restrictions shall
recite that no excavation, regrading or alteration of the Site,
or any portion thereof, shall be conducted without the prior
written approval of EPA. The continuing need for these
restrictions shall be re-evaluated during the Five-year Site
reviews which are conducted under CERCLA Section 121(c), 42
U.S.C. Section 9621(c).
8. Ground Water Monitoring
A long-term ground water monitoring program shall be implemented
to evaluate the protectiveness of the remedy. EPA shall
determine the exact location of monitoring wells, residential
wells and sampling points to be included in the monitoring
program. The frequency and duration of sampling and the
analytical parameters and methods to be used shall be subject to
written approval by EPA.
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37
Five-Year Review
Reviews shall be conducted no less than every five years after
the initiation of the remedial action to ensure that the remedy
continues to protect human health and the environment, unless
otherwise directed by EPA.
X. STATUTORY DETERMINATIONS
Section 121 of CERCLA requires that a selected remedy:
• be protective of human health and the environment;
• comply with ARARs;
• be cost-effective;
• utilize permanent solutions and Alternative treatment
technologies or resource recovery technologies to the maximum
extent practicable; and
• address whether the preference for treatment as a principal
element is satisfied.
A description of how the selected remedy satisfies each of the
above statutory requirements is provided below.
The selected remedy for the Site will be protective of human
health and the environment through: treatment of VOC
contaminated soils to a level that will not affect ground water
together with construction of a slurry cutoff wall around areas
where TCB concentrations, unless contained, would affect ground
water; capping of the process area and the spray fields to
eliminate direct exposure pathways to contaminated soils;
reduction of leaching of contaminants to ground water by reducing
the transport mechanism for the Site contaminants to the aquifer;
and elimination of the potential for erosion of contaminated soil
in the East and West Tributaries of Rapp Creek.
Routine ground water and surface water monitoring near the Site
will continue to ensure the detection of any contamination which
might pose a threat to human health and the environment. None of
the offsite residential wells evaluated presently exceed safe
drinking water standards.
B. Compliance with Applicable or Relevant and Appropriate
Requirements
All applicable or relevant and appropriate requirements (ARARs)
pertaining to the selected remedy for the Revere Chemical Site
AR30U985
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pertaining to the selected remedy for the Revere Chemical Site
will be attained. The ARARs are presented below.
Action Specific
Offsite treatment, storage, and disposal will comply with RCRA
regulations and standards for owners and operators of hazardous
waste treatment, storage, and disposal facilities, in accordance
with 25 PA Code Chapter 264, Subchapters A-E, Subchapter I
(containers), and Subchapter J (tanks).
National Primary and Secondary Ambient Air Quality requirements,
40, C.F.R. 50 et seq.. arp applicable and must be met for the
discharge of contaminants into the air. Pennsylvania's Air
Pollution Control Act is also applicable, as are Pennsylvania's
Air Pollution Control Regulations at 25 Pa. Code §§ 121.1, 121.2,
121.7. 121.8 - General Provisions, Part 123 - Standards for
Contaminants; and 127.1, 127.11. 127.12(a)(5) - Construction,
Modification, Reactivation and Operation of Sources.
The requirements of Subpart AA (Air Emission Standards for
Process Vents) of the Federal RCRA regulations set forth at 40
CFR Part 264, Subpart AA are relevant and appropriate depending
on the level of organics in the contaminated soil. These
regulations require that total organic emissions from the air
stripping process vents must be less than 1.4 kg/hr (3 Ib/hr) and
2800 kg/yr (3.1 tons/yr).
25 Pa. Code § 123.31 prohibits the emission of malodorous
contaminants from crossing the property line.
25 Pa. Code § 127.11 will apply. These Commonwealth of
Pennsylvania regulations require a plan for approval for most air
stripping and soil venting/decontamination projects designed to
remove volatile contaminants from soil, water, and other
materials regardless of emission rate.
25 Pa. Code § 127.12(a)(5) will apply to new point source air
emissions that result from implementation of the remedial
alternatives listed above. Ihese Commonwealth of Pennsylvania
regulations require that emissions be reduced to the minimum
obtainable levels through the use of best available technology
("BAT") as defined in 25 PA. Code S 121.1.
The following Residual Waste Regulations are relevant and
appropriate for capping: Standards for cap, final cover and
grading: 25 PA Code §§ 288.234, 288.436, and Appendix A Table II;
Standards for revegetation: 25 Pa Code SS 288.236 and 288.237;
Standards for water quality protection: 25 PA Code SS 288.241 and
288.244; Standards for ground water monitoring: 25 Pa Code
§§ 288.251, 288.254, and 288.257.
AR30<*986
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Implementation of dust controls and erosion and sedimentation
controls during capping and regrading will comply with
Pennsylvania Department of Environmental Resources' Chapter 102
regulations as explained in the Erosion and Sediment Pollution
Control Program Manual dated April 1990 (as authorized under the
Clean Streams Law, 35 P.S. § 691.202 et.seq.)
Regulations for onsite handling and removal of asbestos at 40 CFR
Part 61.141, Subpart M are applicable.
RCRA regulations for the generation and transportation of
hazardous wastes (25 PA Code Chapter 262, Subchapters A and C,
and Chapter 263) and the Department of Transportation Rules for
Hazardous Materials Transport'(49 C.F.R. Parts 107 and 171-179)
are applicable to the offsite disposal of drums and solid waste.
The Toxic Substances Control Act ("TSCA") of 1976, 15 U.S.C.
§§ 2601 to 2671, establishes regulations at 40 C.F.R. Part
761.60, Disposal Requirements; 761.65, Storage for Disposal;
761.207, General Manifest Requirements.
Fugitive dust emissions generated during remedial activities will
be controlled in order to comply with fugitive dust regulations
in the federally-approved State Implementation Plan for the
Commonwealth of Pennsylvania, 25 PA Code SS 123.1 - 123.2, and
will not violate the National Ambient Air Quality Standards for
particulate matter, 40 C.F.R. SS 50.6 and 25 PA Code SS 131.2 and
131.3.
This remedy will comply with the ground water monitoring
requirements in 25 PA Code Chapter 264, Subchapter F.
Location Specific ARARS
This Alternative will comply with the provisions for protection
of wetlands and flood plain management in 40 C.F.R. Parts 6 and
230 and 25 PA Code SS 105.17-105.20(a). It will also comply with
erosion control requirements related to excavation activities in
25 PA Code Chapter 102.
The Endangered Species Act of 1973, 16 U.S.C. S 1651 et sea.. may
be applicable if a determination is made that endangered species
will be affected by Site remediation.
To Be Considered ("TBC") Standards
The remedy for the Revere Chemical Site is expected to comply
with the applicable portions of the PADER Ground Water Quality
Protection Strategy, which prohibits continued ground water
quality degradation, since treatment of the VOC-contaminated soil
in conjunction with the cap is expected to meet ground water
ARARs.
flR30U987
-------
40
This remedy will comply with CERCLA S 121(d)(3) and with EPA
OSWER Directive #9834.11, both of which prohibit the disposal of
Superfund Site waste at a facility which is not in compliance
with §§ 3004 and 3005 of RCRA and all applicable State
requirements.
Existing wells which serve no useful purpose will be properly
plugged and abandoned consistent with FADER's Public Water Supply
Manual, Part II, Section 3.3.5.11.
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 S300.430(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 the selected remedy is
$11,152,894. A cost estimate is present in Table 17.
D. utilization of Permanent Solutions and Alternative treatment
The remedy selected provides the best balance of trade-offs among
the alternatives evaluated with respect to the evaluation
criteria. Of those alternatives evaluated that are protective of
human health and the environment and meet ARARs, the selected
remedy provides the best balance with regard to long-term and
short-term effectiveness and permanence, cost, implementability,
reduction in toxicity, mobility, or volume through treatment, and
preference for treatment as a principal element.
Under the selected alternative, S6, the insitu vacuum extraction
of VOCs from contaminated soils is a treatment technology which
permanently reduces the toxicity, mobility and volume of VOCs in
the soil. The capping of the Site to mitigate threats posed by
metals-contaminated soils and the use of the slurry wall to
contain TCB which is not amenable to vacuum extraction is
consistent with Superfund program policy regarding principal and
low level threat waste in that it utilizes engineering controls
for low level threat waste.
B. Preference for Treatment as a Principal Element
The Selected Remedy satisfies, in part, the statutory preference
for treatment as a principal element. The Selected Remedy
addresses the primary threat of future direct contact,
ftR30l*988
-------
41
inhalation, and ingestion of contaminated ground water and
exposure to VOC-contaminated soil through treatment of VOC-
contaminated soils to levels that will not impact ground water.
Since the metals-contaminated soil does not constitute a
principal threat, treatment is not required.
XI. EXPLANATION OF SIGNIFICANT CHANGES
The following significant changes have been made to the Selected
Remedy from the preferred alternative described in the Proposed
Plan.
The Proposed Plan presented the remedy for the Site as one
operable unit that was a final remedy. EPA has separated the
Site into two operable units. The Selected Remedy addresses
contaminated so1'! which is defined as Operable Unit One. The
Selected Remedy does not include a ground water component as
described in the Proposed Plan. Operable Unit Two will address
contaminated ground water and contamination in the stream
corridor. EPA is deferring the selection of a remedy for
Operable Unit Two until additional data is gathered and
evaluated. This change was made in response to comments received
by the Agency.
AR30tt989
-------
TABLE 1
SUMMARY OF CONCENTRATIONS IN PROCESS AREA SOIL (INTERVAL
A)
a*«
y^jU^DlfltXIB
ABQBOBV
ATMOIC
Banum
Beryllium
C^dBltUD
Chromium
Cotelt
^^^^^*
Cyaaidft
Lttd
»*___—_^^
Mercury
Nickel
Selenium
SUvtr
Thallium
Viaadium
Ziae
11 1 T««kl<»M
, l.i-TfK&IOrOKUM
2-H«UDOM
Aetna.
BWM
EtbyJbvuH*
M«tayl«M chlorid*
StyrvM
TtmchlonwhM
TolMM
Noateof
Saaniti
o^l^OT^
120
120
120
120
120
120
120
120
120
41
120
120
120
120
120
120
120
120
120
14
14
14
14
14
14
14
14
14
sr=
120
24
120
119
119
26
120
120
120
25
119
120
103
120
32
29
4
120
120
2
2
26
2
1
S6
3
4
15
Mm
(mfftD
22612.50
9.31
1.27
71.43
9.15
O.S5
995.75 '
11.51
2514.95
2.67
133.22
623.41
0.71
54.71
0.41
1.67
0.96
215.60
96.24
0.01
0.02
0.03
0.01
0.01
0.01
0.01
0.01
0.01
ffifbmt
Vata.
(•t/kf)
47400.00
95.00
63.00
200.00
170.00
24.00
17000.00
200.00
jlflOQJ»
21.00
1500.00
5010.00
31.70 N
1000.00
3.20
22.00
2.40
2600.00
570.00
0.75
1.50
1.50
0.75
0.75
0.69
0.75
0.75
0.75
AAW01C65/1
AR3050I6
-------
TABLE 1
SUMMARY OF CONCENTRATIONS IN PROCESS AREA SOIL (INTERVAL A)
i
Nooter of
84
84
86
86
40
86
86
86
86
86
86
86
40
86
86
86
86
86
86
16
86
40
86
40
64
64
64
38
2=5
2
9
10
4
2
I
2
2
6
3
6
1
3
21
3
8
11
3
9
1
I
1
9
1
1
12
3
1
M«B
(aj/kf)
0.01
0.11
0.26
0.26
0.38
0.26
0.26
0.26
0.25 .
0.26
0.25
0.26
1.49
0.41
0.26
0.25
0.24
0.29
0.25
0.24
0.25
0.30
0.25
0.02
0.10
OJ8
0.19
0.05
Rifta
V«Ja»
(Bf/kf)
vp.75^
9.10
2.30
2.30
4.80
2.30
2.30
2.30
2.30
2.30
2.30
2.30
11.50
4.50
2.30
2.30
130
130
IX
1.05
130
1.60
130
0.20
1.40
uo
1.00
1JO
AAW01C65/2
HR3050I7
-------
TABLE 2
SUMMARY OF CONCENTRATIONS IN EAST SPRAY FIELD SOIL (INTERVAL A)
Q— '
AJumm
Andaoay
Anaoic
Barium
Beryllium
fmAftitmt
Chromium
Cobalt
Copper
Cyanide
Laad
Maafaneee
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zioc
Acetone
Methylene chloride
Toluene
Beoaoicaod
fTW>_^l» Ik*, nntirtulm
oufi-utiy uMiy i jfoouuu
DiHHbotylpodMlait
Di-o-octyipbthaiatt
Fluonadxne
Py«
Niontarof
Sampiaa
29
29
29
29
29
29
29
29
29
8
29
29
29
29
29
29
29
29
28
15
15
15
8
15
15
15
15
15
£5
29
5
29
29
29
1
29
29
29
3
29
29
24
29
10
1
1
29
28
7
11
1
3
1
1
1
1
1
(af/kf)
23672.41
8.12
11.79
77.55
1.53
0.32
64.72
10.14
1125.48
0.47
25.23
713.21
1.54
23.21
0.53
1.13
1.14
75.66
64.61
0.01
0.01
0.00
0.71
0.22
0.21
0.21
0.21
0.21
(mf/kf)
40200.00
13.50
26.00
150.00
3.20
1.40
690.00
21.00
27000.00
1.50
76.00
2030.00
30.00
84.00
1.40
2.30
4.60
140.00
160.00
0.03
0.01
0.00
1.10
0.30
0.30
0.30
0.25
0.25
AAW01C65/3
AR3050I8
-------
TABLE 3
SUMMARY OF CONCENTRATIONS IN SOUTH SPRAY FIELD SOIL (INTERVAL A)
Chemical
Aluminum
Antimony
Arsenic
Banum
Beryllium
Chromium
.CotMlt
Comer
^*"Kr**
Cyanide
LMd
Maafaoeee
Mercury
Nickel
Seleoium
Silver
Thallium
Vanadium
Zinc
Acetone
Methyiene chloride
1.2.4-Tricalorobeaaoe
Bu<2-ediylb«yl)ptaB«
la»
Number
of
Sample*
16
16
16
16
16
16
16
16
8
16
16
16
16
16
16
16
16
16
10
10
10
10
Number
Detected
16
1
15
16
16
16
16
16
1
16
16
12
16
4
1
I
16
16
2
10
1
1
Men
(mj/kf)
22993.75
6.20
3.70
79.38
0.96
45.56
9.12
100.13
0.29
19.78
501.31
0.77
19.75
0.27
0.91
0.89
56.31
57.88
0.01
0.005
0.26
0.20
Hifhen
Value
(mf/kf)
39300.00
8.50
6.00
130.00
1.70
170.00
15.00
360.00
0.53
51.00
1100.00
2.50
34.00
0.68
1.45
2.90
120.00
95.00
0.02
0.01
0.70
0.23
AAW01C65/4
8R3050I9
-------
Table 4 -•""
MATRIX OF POTENTIAL EXPOSURE ROUTES FOR THE
REVERE CHEMICAL SITE
CURRENT SITE CONDfTIONS
ExpoMra MadiuaV
E^oaon-RoMr
Ooundwattr
Ingeatraa
Dermal Coaiaa
Inhalation Dunnf Showering
Surface Wuff
Lngcauoa
Dermal Coataci
Scdoaa
Incideaal lagceioo
0«niui Coooct
Alt
InJuUtioa of Viper
PhaM Cheaictlf
ladeoff
Outdoor*
Inhalation of
PuoculMa
lodeon
Ovtdoen
Soiimna
Iocid«nal Ia|Mioa
Derail Contaa
EflBtf
IngMTion
Ft*
M«(«adGr
-------
Table 5
MATRIX OF POTENTIAL EXPOSURE ROUTES~FOR THE
REVERE CHEMICAL SITE
FUTURE SrTE CONDITIONS
Expoav* Madaw/
Expo«uvRo
-------
TABLE 6
SUMMARY OF ESTIMATED LIFETIME CANCER RISKS
Current Land Use
Process Area - Trespasser
Chemical
Antimony
Beryllium
Cadmium
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Vanadium
Carcinogenic PAHs
PCBs
Trichloroelhene
Tetrachloroethene
lenzene
Inhalation - Inhalation - Inhalation - Soil Dermal Contact
Showering Outdoor Air Indoor Air Ingastion with Soil
188E08 159EO«^ O.OOE + 00
1.29E-09 V '"
4.10E-10 4.78E08 4.78E-08
/T.63E-09^j 366E08 3.66E-08
2.56E-10
4.97E-11
2.56E-1I
O.OOE + 00 2.2SE08 O.OOE + 00 1.67E-06 B.44E-08
Crop Fish Total Risk
(novation Inoaatkm by Chemical
1 61EO6
1.29E 09
960E08
7 49E 08
256E 10
497E 11
2.56E-11
O.OOE + 00 O.OOE+00 1.78E-06
IE 06 = 0.000001
CM
CM
O
tn
O
CO
or
-------
TABLE 7
SUMMARY OF ESTIMATED LIFETIME CANCER RISKS
Current Land Us*
S. Spray FMd - Trespasser
Chemical
Inhalation • Inhalation • Inhalation • Soil
Showering Outdoor Air Indoor Air Inpestion
Dermal Contact
with Soil
Crop Hah Tout Risk
Inpestton Ingettton by Chemical
Antimony
Beryllium
Cadmium
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Vanadium
Carcinogenic PAHs
PCBs
Trichloroethene
Tetrachloroethene
Benzene
1.88E08
1.29E09
4 JOE 10
1.63E09
2.56E 10
4.97E-H
2.56E-11
I 88E08
1.29E-09
4.10E 10
1 63E09
2.56E-10
497E 11
256E11
OOOE40Q 2.2SE-OB O.OOE^OO O.OOE + 00 O.OOEfOO O.OOE *00 O.OOE + 00 2.26E-08
IE 06 - 0.000001
CO
CM
O
LO
O
CO
cc
-------
TABLE 8
SUMMARY OF ESTIMATED LIFETIME CANCER RISKS
Current Land Us*
E. Spray Field • Trespasser
Chemical
Antimony
Beryllium
Cadmium
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Vanadium
Carcinogenic PAHs
PCBs
Trichloroethene
Tetrachloroethene
9enzene
Inhalation • Inhalation -
Showering Outdoor Air
188E08
1.29E-09
4.10E-10
1.63E09
2.56E-10
4.97E-I1
2.S6E It
O.OOE + 00 2.25E08
Inhalation- SoM Dermal Contact Crop Fish Total Risk
Indoor Air Ingestion with SoM Ingestion (notation by Chemical
1 88E 08
1.29E09
4.10E-10
1 63E 09
2.S6E-10
4.97E-11
2.56E-11
OOOE + 00 OOOE+00 OOOE+00 OOOE + 00 O.OOC + 00 2.25E-08
IE 06 = 0.000001
Oil
O
in
o
CO
ac
-------
TABLE 9
SUMMARY OF ESTIMATED LIFETIME CANCER RISKS
Future Land UM
On-sita Resident
Chemical
Groundwatar Surface Water Surface Water Dermal Contact with Dermal Contact with
liHjenton Inpestten Inpestton • Swimming Water • Swimming Water • Showering,
Antimony
Beryllium
Cadmium
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Vanadium
Carcinogenic PAHs
PCBs
Trichloroethene
Tetrachloroethene
Benzene
Bis(2-ethylhexyl|phthala
5.93E06
O.OOE + 00
LO
CM
O
LO
O
CO
0=
act
2.34E05
7.37E-06
7.70E-07
OOOE*00
Total
l>y Pathway
3.67E05
OOOE400
OOOE + 00
O.OOE + 00
7.70E-07
IE 06 « 0.000001
-------
TABLE 9 (conl'd)
SUMMARY OF ESTIMATED LIFETIME CANCER RISKS
Future Land U«e
Oa-ilie Reildeil
Chemical
Antimony
Beryllium
Cadmium '
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Vanadium
Carcinogenic PA! Is
PCBs
Trichloroethene
Tetrachloroethene
Benzene
Bis(2-ethylheKyl)ph(halate
Inhalation -
Showering
OOOE+OO
OOOE+OO
OOOE+OO
OOOE+OO
3.62E-05
O.OOE+00
3.62E-05
Inhalation -
Outdoor Air
2.07E-06
I.42E-07
4.5IE-OB
I.79E-07
2.B2E-OI
5.47E-09
282E-09
248E-06
Inhalation- Soil Dermal Contact Crop Firfi Total RiA
Indoor Air Ingestion with Soil mgestion Incnlion byCbeakal
4.I3E-05 OOOE+OO 2.IIE-05 7.WE-05
I42E-07
I.42E-06 I.42E-06 4.I9E-07 33IE-06
4.53E-06 4.53E-06 203E-05 295E-05
605E-05
547E-09
2.I2E-09
7.37E4»
OOOE+OO 473E-05 S.95E4>6 4.I7E-05 O.OOE+00 I.7II-M
IE-06 = 0000001
tip
CM
in
CD
cc
-------
TABLE 10
SUMMARY OF ESTIMATED HAZARD QUOTIENTS
Currant Land Use
Process Area • Trespasser
Chemical
Antimony
Beryllium
Cadmium
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Vanadium
Carcinogenic PAHs
PCBs
Trichloroethene
Tetrachkuoethene
Beniene
Inhalation - Inhalation - Inhalation -
Showering Outdoor Air Indoor Air
326E05
' 313E08
2.96E06
2.90E + 00 (
1.08E04
2.44E08
1 06E 05
4.14E-06
842E07
4.4BE-05
1 05E05
Soil Dermal Contact Crop Fish
Ingestion with Soil Ingestkm Ingestion
810E03
5.17E-04 '
4.48E=OC^^
'^B.22E-Q2i)
"TI3E-02
376E06 3.76E-06
6.82E-04
7.18E-04
1 48E04
8 08E 03
Total Hward
Quotient
JLME-03_
A20E-O4y
4.49E04
2.96E4QQ
1 84E 02
755E06
692E04
722E04
1 47E04
812E03
1.05E-05
1E-06 ~ 0.000001
CM
O
tf>
O
CO
OC
-------
TABLE 11
SUMMARY OF ESTIMATED HAZARD QUOTIENTS
Current Land Us*
E. Spray Field • Trespasser
Chemical
Antimony
Beryllium
Cadmium
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Vanadium
Carcinogenic PAHs
PCBs
Trichloroethene
Tetrachloroethene
Benzene
Inhalation • Inhalation • Inhalation -
Showering Outdoor Air Indoor Air
326E05
3.13E06
2.98E06
2.90E + 00
1 08E 04
2.44E08
1 06E 05
4.14E-06
8.42E-07
4.48E-05
1 05E 05
SoM Dermal Contact Crop Fish Total Hazard
digestion with SoH Ingestkm Ingestion Quotient
3.26E-OS
3.13E-06
2.96E06
3.39E-03 2.91E + 00
7.98E-03 8.08E-03
2.44E08
1.3SE-03 1.36E-03
3..04E-04 308E04
8.42E-07
2 83E03 288E03
1.05E-OS
IE 06 = 0.000001
09
-------
TABLE 12
SUMMARY OF ESTIMATED HAZARD QUOTIENTS
Currant Land Uae
8. Spray Field • Trespasser
Charnical
Antimony
Berytlium
Cadmium
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Vanadium
Carcinogenic PAHs
PCBt
Trichloroethene
retrachloroethene
Benzene
Inhalation - Inhalation • Inhalation •
Showering Outdoor Air Indoor Air
326E05
' 313E06
296E06
2.90E + 00
1 .08E-04
2.44E08
1 06E 05
4 HE 06
8.42E-07
4.48E-05
1 .05E-05
Soil Dermal Contact Crop Fish Total Haiafd
Inoestion with SoN (notation Inoaation Quotieot
326E05
3.13E06
296E06
239E03 2.90E + 00
7.10E-04 8.18E04
244E08
6 73E 04 6 84E 04
259E04 263E04
8.42E07
2.11E-03 2.15E03
1 05E 05
IE 06 - 0.000001
CSJ
CD
in
CD
OO
CC
-------
TABLE 13
SUMMARY OF ESTIMATED HAZARD QUOTIENTS
Future Lend Us*
On-efte Resident
Chemical
Ground wreter
Ingestion
Surface Water
digestion
Surface Water
Ingestion • Swimming
Antimony
Beryllium ' 6.43E-04
Cadmium
Chromium 7.60E-01
Copper 2.4SE-01
Cyanide
Lead
Mercury 1.17E02
Nickel 7.78E-03
Silver
Vanadium 3.33E-02
Carcinogenic PAHs
PCBs
Trichloroethene
Tetrachloroethene
Benzene
Bis|2-ethylhexyl)phthala 6.14E-03
Dermal Contact with
Water - Swimming
Dermal Contact with
Water • Showering
O
CO
O
in
O
CO
QC
•at
1E-06 - 0.000001
-------
TABLE 13
SUMMARY OF ESTIMATED HAZARD QUOTIENTS
Future Land Us*
On-slte Resident
Chemical Inhalation •
Showerlno
Antimony
BerylHum '
Cadmium
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Vanadium
Carcinogenic PAHs
PCBa
Trichloroethene
Tetrachloroethene
Benzene
Bi«(2-ethvlhenyl)phthala
Inhalation - Inhalation -
Outdoor Air Indoor Air
1 20E03
1 15E04
1.09E04
1.07E + 02
398E03
895E07
388E04
1.52E04
309E05
1 64E03
387E04
Soil
Inoestkm
468E02
448E03
3 51 E 03
5 1 1E 01
3.09E-01
4.19E05
455E03
536E03
1.10E03
682E02
Dermal Contact Crop Fiah
with SoM Inoestkm Ingestkm
5.03E-01
242E03
1.89E-01
8.24E01
2.76E + 01
4 19E05
3.26E-01
1.15E-01
3.97E-02
733E02
Total Hazard
Quotient
S.SOE-01
7.66E-03
1.92E-01
L09E+02
2.81E + 01
B.47E-OS
3.43EO1
1.28E-OI
408E02
1 76E01
387E04
6 ME 03
IE-OB - 0.000001
CO
O
in
O
CO
OC
-------
COMPARISON OF INORGANIC ANALYTICAL RESULTS OF
SURFACE WATER TOXICfTY SAMPLES-TO
BACKGROUND SURFACE WATER SAMPLES
REVERE CHEMICAL SITE
REVERE, PENNSYLVANIA
(all concentrations in ug/1)
SAMPLE DESIGNATION
TAL METALS CONCENTRATIONS
(il
BACKGROUND CONCENTRATION19
TEHO020A - Unfirtered
Calcium-12.200
Chromium - 4.30 J
Copper - 8.70 J
Magnesium • 5,040
Potassium - 1.550 J
Sodium - 7.3OO J
11.000
4.69O
1.470
6.56O
TEHO020A - Unfiltered
Calcium- 12.300
Copper - 6.1O J
Sodium- 7.010 J
11.000
6.080
TEH002RA - Unfiltared
Barium - 8.20 J
Calcium- 12.100
Magnesium - 4.880 J
Sodium - 6.9OO J
7.80
11.0OO
4.69O
6.560
TEH002RA - Rltered
Arsenic - 2.10 JL
Calcium- 12.1OO
Copper - 6.40 J
Mercury - 0.10 J
Sodium - 6.810 J
2.10
11.000
0.10
6.080
TEHO030A - Unfiltared
Arsenic - 1,60 JL
Barium - 8.30 J
Copper - 78.2
Lead • 2.80 J
Manganese - SI .4
Potassium - 1.450 J
Sodium- 16.700 J
Zinc- 17.5 J
37.7
16.700
TEHO030A - Filtered
Aluminum - 738 K
Arsenic - 1.40 JL
Barium- 14.1 J
Copper-98.1
Iron - 634
Lead - 2.50 J
Manganese - 66.6
Nickel- 18.2J
Potassium- 1,530 J
Zinc-31.3
TEHOO4OA - Unfiltered
Arsenic- 1.10 JL
Barium - 9.70 J
Calcium- 15.OOO
Copper - 98.8
Lead-2.10 J
Manganese - 97.7
Nickel- 14.0J
Potassium - 1.370 J
Zinc - 45.O
14.8OO
37.7
TEHO040A - Filtered
Aluminum - 505 K
Arsenic - 1.40 J
Barium - 11.5 J
Copper - 169
Iron - 452
Lead - 2.5O J
Manganese - 95.8
Potassium - 1.440 J
Zinc - 26.3
flR305032
-------
TABLE 14 (eoofdj
COMPARISON OF INORGANIC ANALYTICAL RESULTS OF
SURFACE WATER TOXICTTY SAMPLES TO
BACKGROUND SURFACE WATER SAMPLES
REVERE CHEMICAL SITE
REVERE. PENNSYLVANIA
SAMPLE DESIGNATION
TEHOOSOA • Unffltered
TEH0050A - Filtered
TEHO060A - Unfiltered
TEH0060A - Filtered
TEHOO6RA • Unfiltered
(replicate of TEHO06OA)
TEH006RA - Filtered
(replicate of TEH006OA)
TAL METALS CONCENTRATIONS*11
Barium- 11.1 J
Calcium- 14.700
Copper -54.3
lMd-3.80
Magnesium - 5,350
Manganese- 52 J
Mercury -0.4O —
Nickel- 18.0 J
Potassium - 1 .470 J
Sodium - 9.850 J
Zinc - 20.3
Calcium- 16.20O
Copper - 66.9
Mercury- 0.10 J —
Sodium - 10.0OO
Calcium- 12.70O
Copper - 66.4
Lead - 3.92 B
Magnesium - 5.1 50
Copper - 82.5
Calcium -13.900
Copper- 103
Lead - 2.79 BJ
Magnesium - 5.490
Copper - 84.7
Mercury - 0.17 J —
BACKGROUND CONCENTRATION19
7.80
11.OOO
4.690
23.0
0.20
1.470
6.560
20.1
11.OOO
O.IJD
6.080
11.OOO
4.69O
_
11.000
4.69O
0.10
Explanation:
J The associated numerical value is an estimated quantity.
B The result is qualitatively suspect because the compound was detected in a field and/or laboratory blank at a similar concentration.
K The associated numerical value is biased high.
L The associated numerical value is biased low.
D The sample was diluted to bring the compound into the linear calibration range.
Background concentration for indicated parameter has not been established. Parameter was not detected in any of the background
samples that were used to determine the representative background concentrations.
Note:
1. This table summarizes TAL metals detected at each sampling location that exceeded the respective background concentration.
2. Background level for TEHO020A was determined based on background samples collected from the west tributary during the Phase
I Rl (two samples, each designated R1U) and the Phase II Rl (TEHOO1OA). Background level for TEH0030A and TEHO04OA were
determined based on background sample collected from the east tributary during the Phase I Rl (2 samples, each designated R2U).
Background level for TEHOOSOA and TEHOO60A was determined based on background samples collected from both tributaries
during the Phase I Rl and the Phase II Rl.
AAW031F7
AR305033
-------
TABLE 15
COMPARISON OF INORGANIC ANALYTICAL RESULTS OF
STREAM SEDIMENT TOXICITY SAMPLES TO
BACKGROUND STREAM SEDIMENT SAMPLES
REVERE CHEMICAL SITE
REVERE, PENNSYLVANIA
(all concentrations in mg/kg)
SAMPLE DESIGNATION
TESO020A
TESOO20RA
(Replicate of TESO020A)
•
'
TESOO30A
TAL METAL CONCENTRATION*11
Aluminum - 25,300 0
Arsenic- 9.12 OJ
Banum - 305
Beryllium - 2.41
Cadmium - 0.41
Calcium - 2.070
Chromium - 86.3
Cobalt • 64.4
Copper - 1 1 1
Iron - 65.5OO OJ
Lead - 39.1
Magnesium - 12.500
Manganese - 6.650 0
Nickel- 48.1
Potassium - 1 .270
Vanadium- 117
?mc - 228
Aluminum'- 24.300 0
Arsenic - 12.9 J
Barium - 65.1
Beryllium -1.91
Calcium • 1.490
Chromium • 104
Cobalt - 28.4
Copper -161
Iron- 55.100 OJ
Lead • 27.6
Magnesium- 13.200
Manganese - 1 .920 O
Mercury - 1 .87 L
Nickel - 48.5
Potassium - 1 .000 J
Sodium - 43.0 J
Vanadium - 1 10
Zinc - 188
Aluminum • 31.700 0
Arsenic - 44.9 OJ
Beryllium • 7.26
Chromium - 80. 1
Cobalt - 73.8
Copper • 1 .500 0
Iron • 65.500 OJ
Magnesium- 14.600
Manganese • 3.570 0
Metcuiy - 0.06 JL
Nickel • 65.4
Potassium - 730 J
Sodium • 51.5 J
Vanadium • 1 08
Zinc - 142
BACKGROUND LEVEL18
11,200
7.6O
59.1
0.71
-
894
25.6
1O.7
12.4
23.20O
13.0
3.910
534
13.2
995
47.9
78.6
11.200
7.60
59.1
0.71
894
25.6
10.7
12.4
23,200
13.0
3.910
534
-
13.2
995
31.5
47.9
78.6
16.200
23.4
1.50
36.7
14.8
25.2
36.200
6.960
1.580
-
18.1
-
-
73.5
106
AR30503U
-------
TABlf 15 (confd)
•<% - .-• -
COMPARISON OF INORGANIC ANALYTICAL RESULTS OF
STREAM SEDIMENT TOXICITY SAMPLES TO
BACKGROUND STREAM SEDIMENT SAMPLES
REVERE CHEMICAL SITE
REVERE, PENNSYLVANIA
SAMPLE DESIGNATION
TES0040A
TESOOSOA
TESOO60A
TESO06RA
(replicate of TES0060A)
TAL METAL CONCENTRATION111
Aluminum - 31.700 0
Arsenic - 39.1 OJ
Barium - 93.7
Beryllium- 10.2
Cadmium - 1.12 J
Chromium - 131
Cobalt - 90.6
Copper • 2.560 0
Iron- 64. TOO DJ
Lead - S2.0
Magnesium - 17.700
Manganese - 4.610 D
Mercury -0.1 2 L
Nickel - 89.2
Potassium - 1,110
Sodium - 6O.S J
Vanadium- 144
Zinc -21 9
Aluminum - 36, ZOO O
Arsenic - 45.7 OJ
Barium - 81.7
Beryllium • 8.56
Calcium- 1.160
Chromium - 336
Cobalt - 60.1
Copper- 1.160O
Iron - 85.9OO OJ
Lead - 35.4
Magnesium- 16,800
Manganese - 3,440 0
Nickel - 69.3
Sodium - 32.3 J
Vanadium - 206
Zinc - 222
Copper - 1.170
Mercury - O.O7 J
Copper - 1.010 .
Mercury - 0.06
BACKGROUND LEVEL121
16.200
23.4
8S.6
1.SO
1.10
36.7
14.8
25.2
36.200
47.4
6,960
1.580
-
18.1
-
-
73.5
106
11.200
7.60
S9.1
0.71
894
25.6
10.7
12.4
23.2OO
13.0
3,910
534
13.2
31.5
47.9
78.6
12.4
.—
12.4
™
Explanation:
J The associated numerical value is an estimated quantity.
B The result is qualitatively suspect because the compound was detected in a field and/or laboratory blank at a similar
concentration.
K The associated numerical value is biased high.
L The associated numerical value is biased low.
0 The sample was diluted to bring the compound into the linear calibration range.
Background concentration for indicated parameter has not been established. Parameter was not detected in any of the
background samples that were used to determine the representative background concentrations.
Notes:
1. This table summarizes TAL metals detected at each sampling location that exceed the respective background
concentration.
2. Background level for TESOO20A was determined based on background samples collected from the west tributary during
the Phase I Rl (sample B1) and the Phase II Rl (sample TESOO10A). Background levels for TES0030A and TESOO4OA
were determined based on background sample collected from the east tributary during the Phase I Rl (sample B2)
Background level for TESOOSOA and TES006OA was determined based on background samples collected from both
tributaries during the Phase I Rl and the Phase II Rl. AAW031 F7
AR305035
-------
16
MCE SUMMARY
COMPARISON OF ANALYTICAL RESULTS FOR SURFACE WATER
TOXICTTY SAMPLES TO PENNSYLVANIA WATER QUALITY CRITERIA
FOR TOXICfTY SUBSTANCES (FISH AND AQUATIC LIFE CRITERIA)
REVERE CHEMICAL SITE
REVERE. PENNSYLVANIA
(an
ntrations in ug/l)
SAMPLE
TEH0010A - Unftttered
TEH0010A- Filtered
TEH0020A - Unf iltered
TEH0020A - Filtered
TEH002RA • Fittered
TEH0030A - Unfihered
TEH0030A - Filtered
TEH0040A - Unf iltered
TEH0040A • Filtered
TEH0050A - Unfittered
TEH0050A - Filtered
TEH0060A - Unf iltered
TEH0060A • Filtered
TEH006RA • Unfittered
TEH006RA - Filtered
TAL METALS CONCENTRATION
Mercury - 0.20 J
Lead - 8.30
Copper - 8.70 J
Lead - 3.40
Lead - 3.20
Copper - 78.2
Lead - 2.80 J
Copper - 98.1
Lead • 2.5 J
Copper - 98.8
Lead • 2.1 J
Copper- 169
Lead - 2.5 J
Copper - 53.4
Lead - 3.8
Mercury • 0.4
Copper - 66.9
Copper - 66.4
Lead • 3.92 B
Copper • 82.5
Lead - 5.61
Copper - 103
Lead - 2.79 BJ
Copper- 84.7
Lead • 3.92 J
Mercury -0.17 J
OVTEMA CONTMUOUS*
CONCBfTRATION
0.012
1.3
0.67
1.4
1.3
7.3
1.6
7.3
1.6
7.6
1.7
7.6
1.7
7.5
1.7
0.012
7.5
6.9
1.4
6.9
1.4
7.3
1.6
7.3
1.6
0.012
Explanation:
* Taken from Pennsylvania Code, Title 25 - Environmental Resources, Chapter 16 - Water Quality Toxics Management
Strategy, Appendix A. Table 1.
J The associated numerical value is an estimated quantity.
B The associated numerical value is qualitatively suspect as-this compound was detected in a field and/or laoorat
blank at a similar concentration.
AAW031F7
fiR305Q36
-------
Keve * » Chemical Site: Soil emedial Alternatives11'
ALTERNATIVE
SI
S2
S3
S4
S5
" +
S7
S8
S9
DESCRIPTION
- NO ACTION
- EROSION CAP
- OFF-SITE DISPOSAL OF SOLID WASTE
- VE (ORGANIC HOT SPOTS)
- EROSION CONTROL CAP/CLAY CAP SLURRY
WALL
- OFF-SITE DISPOSAL OF SOLID WASTE
- CLAY CAP/SLURRY WALL
- OFF-SITE DISPOSAL OF SOLID WASTE
- IMPERMEABLE CAP/SLURRY WALL
- OFF-SITE DISPOSAL OF SOLID WASTE
• VE (ORGANIC HOT SPOTS)
- CLAY CAP/SLURRY WALL
- OFF-SITE DISPOSAL OF SOLID WASTE
- LTTS (ORGANIC HOT SPOTS)
- EROSION CONTROL CAP
- OFF-SITE DISPOSAL OF SOLID WASTE AND
TREATED SOIL
- LTTS (ORGANIC HOT SPOTS)
- EROSION CONTROL CAP
- ON-SITE DISPOSAL OF SOLID WASTE AND
TREATED SOIL
- VB (ORGANIC HOT SPOTS)
- iN-srru SOIL STABILIZATION
- EROSION CONTROL CAP
- OFF-SITE DISPOSAL OF SOLID WASTE
CAPITAL
COST($)
0
3,769,656
5,240,466
7,780,510
11,249,062
M3M7I
16,252,161
12,735,975
31,320,242
OAMCOST
RANGE ($)
132,915
161,655
161,655 -
944,038
161,655
167,415 -
179,395
161,655-
ttt£52
161,655 -
869,005
161,655 -
869,005
161,655-
1,286,226
PRESENT
WORTH ($)
2,176,144
6,254,843
9,122,139
10,265,697
13,834,050
11,152,894
20,052,584
16,536,398
35,863,182
Table 17
-------
Compound MCL CLP Protocol Drinking Water Method Drinking Mater
CRQL Detection Lisit(l) Method
tig/1 ug/1 HuBber(i)
Trichloro- 5 10 0.14 524.2
ettoylen*
1,2,3-Tri- 0.03 524.2
chlorobeneene
1,2,4-rri-
chlorobenzene 1O 0>O4 524.2
Bis(2-ethylhexyl) 10 0.6 525
pbtbalate
(1) The vetnods listed here are those used by the PADER Bureau of Laboratories
for drinking water analyses. Detection limits listed are those published in
the OSEPA publication/ •Methods for the Determination of Organic Compounds in
Drinking Water", December 1988.
Table 18
ftR305038
-------
Analyte
HCL
(SMCL)
ug/1
CLP Protocol
CRDL
Drinking Hater Method
Detection Limit(1)
ug/1
Drinking Water
Method
Ku*ber(l)
AluaimuQ
Antiaony
Arsenic
Barium
Beryl liua
Cadmium
calciuo
Chromiua
Cobalt
Copper (2)
Iron
Lead(2)
Kagnesiua
Manganese
Mercury
Vickel
Potassium
diver
SodiuB
Thallitia
VanadiuB
zinc
50
1000
50
13OO(1000)
(300)
15
(50)
2
1O
50
Cyanide (total)
(5000)
200
60
10
200
5
5
5000
10
50
25
100
3
5000
15
0.2
40
5OOO
5
10
5000
10
50
2O
1O
45
2
1
2
O.3
0.1
10
1
7
6
7
4
30
2
1
15
5OO
2
7
29
2
8
2
1
2O0.7
200.8
206.2
200.7
200.7
213.2
200.7
218.2
200.7
20O.7
2OO.7
20O.8
2O0.7
200.7
245.2
200.7
200.7
27O.2
200.7
200.7
2OO.8
2O0.7
200.7
335.3
(1) The above drinking water aethods and their associated detection limits are
those used by the FADER Bureau of Laboratories for drinking water analyses.
may were obtained fro» Dennis Meuin, chief, Metals Section, PADBR Bureau of
Laboratories.
(2) The values given are not MCLs but "action levels" at which public water
mist take action to reduce the contaminant concentration.
Table 19
flR305039
-------
QUAOMNGIE LOCATION
0 1000 2000 3000 FEET
GRAPHIC SCALE
CONTOUR INTERVAL - 20 FEET
IS REFERENCE:
9 A PORTION OF USCS 7.9 MINUTE TOPOGRAPHIC
« MAP; RIECasVlOE AND BCOMMSTER QUADRANGLES,
PENNSYLVANIA; 1956. PHOTDREVISEO 19M AND
197% 1957. PHOTOREVISED 1983; RESPECTIVELY.
TITLE
SITE VICINITY MAP
PROJECT
REVERE CHEMICAL
REVERE. PENNSYLVANIA
SCALE
AS SHOWN
OWN. IT
OATC 9-19-91
R.G.B.
JOB NO.
IAPPR. BY
T.J.G.
19142-002
1
-------
CO
o
en
o
jr
PMPtRTV BOUMOMV
*-• romn timut lAootn
i-tl romm man UMJOON
0 100 100 300 400 HIT
C SCALC
SITE FEATURES MAP
i. MIN cumm «M> MBionc an n*nma
MMimo> CM im noun. rt*iuMS NOT cumMnr
cosmo At mi an MCIUOC IMC ainco MV*.
PROCESS KOVSt MIA. SlOlHOt UOOONS. MOCXSI
UCOOHS. 9M> Pit. AND DC COUtCtm BASINS
i I. IM tunMt or IHC sAT rcu» csRUAifO IKOH
i IKMCW or AC»«I pHoiocninn potaHtio M
P . *ait ANAini* mvtm CMIKU COUPAN*. RCtcpc.
* (USCPA. IMI)
REVERE CHEMICAL
REVERE. PENNSYLVANIA
WILLOW CROVC.PCNNSYLVANIA
DVM. BY
JOB NO.
APPR BY
T.J.G.
no. NO.
19J 42-002.
2
-------
! i ! i i l I I I
tXfLANAIIQM:
—••— rmniin MWBUI>
WW-3 ^ nun i IMMIUHW «cu ioc>noN
u* B 4 nuoi i KMionn Mil UXAIIW
NOIL.
* MMIONMO MU U»-t »«5 AN ovtRBUKOtN Mil
MSruiD DWIINO mi nuv IA iM\unoAnoN.
ANO NOOHuisaowo H HR iiivcw or me ANAI rncAL
waxrs MCKAito mt MXNCI or ANY COUPOUNOS
9 CONCH*
GRAPH 11 SCALE
I I
PHASE-I, 1A AND II
MONITORING WELL LOCATIONS
PROJECT
REVERE CHEMICAL
REVERE. PENNSYLVANIA
SCALE
DA ft
AS SHOWN
9/20/91
WILLOW CHOVE. PENNSYLVANIA
DW. BY
APPR. BT
T.J.G.
JOB NO.
FIG. NO
19142-002
-------
BACKGROUND
* 88
JEET003 /
, /
EXPLANATION;
—— PROPERTY BOUNDARY
FENCE
APPROXIMATE LOCATION OF TOXICITY SAMPLE POINTS;
EET003CZ] SOIL
TES003 * SEDIMENT
TEHOOJd SURFACE WATER . ,
•& BACKGROUND SURFACE WATER AND SEDIMENT
^ SAMPLE LOCATIONS
I
o
TREE CORE SAMPLE AREAS
NOTE;
1. SAMPLING LOCATIONS ARE APPROXIMATE
BASED ON FIELD MEASUREMENT FROM
SURVEYED GRID POINTS.
0 200 400 600 FEET
GRAPHIC SCALE
SURFACE WATER AND SEDIMENT
SAMPLE LOCATIONS
PROJECT
REVERE CHEMICAL
REVERE. PENNSYLVANIA
DAMES & MOORE
WILLOW PROVE. PENHSYlVAHi*
SCALE
AS SHOWN
OWN. BY
R.G.B.
APPR. BY
M.P.
JOB NO,
19142-002
no. NO.
-------
BACKGROUND
* BB
TES001
TES005\/flii
TEH005 '
—— PROPERTY BOUNDARY
FENCE
APPROXIMATE LOCATION OF TQX1CITY SAMPLE POINTS;
EET003CD SOL
TES003 * SEDIMENT
TEH003 O SURFACE WATER
•& BACKGROUND SURFACE WATER AND SEDIMENT
SAMPLE LOCATIONS
TREE CORE SAMPLE AREAS
u
7
tMDb.
1. SAMPLING LOCATIONS ARE APPROXIMATE
BASED ON FIELD MEASUREMENT FROM
SURVEYED GRID POINTS.
0 200 400 600 FEET
SURFACE WATER AND SEDIMENT
SAMPLE LOCATIONS
PROJECT
REVERE CHEMICAL
REVERE. PENNSYLVANIA
DAMES & MOORE
WILLOW OROVt. FENNSYLVAMtA
SCAU
AS SHOWN
DATE
5-19-93
OWN. BY
R.G.B.
APPB. BY
M.P.
JOB NO.
19142-002
no. NO.
4
-------
RESPONSIVENESS SUMMARY
PART It SUMMARY OP THE MAJOR COMMmwa *MD QUESTIONS RECEIVED
DURING THE PUBLIC MEETING AND EPA RESPONSES
This section summarizes the commentors' major issues and concerns
and expressly acknowledges and responds to those issues raised by
the local community. The major issues and concerns on the
Proposed Plan for the Revere Chemical Site received at the August
12, 1993 public meeting and public comment period can be grouped
into five categories:
A. General Clean-Up Concerns
B. Ground Water Clean Up
c. Soil and Solid Waste Clean Up
D. Potentially Responsible Party ("PRP") Issues
E. Superfund Process
F. Future site Usage
The questions, comments, and responses are summarized below.
A. General Clean-up Concerns
• A citizen asked who was monitoring the activities at the
Site on a day-to-day basis.
EPA Response: The Revere Chemical Site does not currently
require someone to be on the Site every day. When the Site is in
the remedial action stage, a qualified person will be on Site
every day to monitor the implementation of the design.
• A citizen asked who would be maintaining the Site operations
after the remedy has been implemented.
EPA Response: EPA usually enters into an agreement with the
responsible parties to conduct the design and implement the
remedy. This remedy will include long-term operation and
maintenance ("O&M"). EPA will oversee the long-term O&M
to ensure that it is being properly implemented and that the
environment is being protected.
• A citizen asked if the company that will be implementing the
remedy has been selected yet.
EPA Response: EPA does not "select" a company to implement the
remedy. Rather, the company or companies responsible for
implementation of the remedy are those companies which have at
one time or another either owned or operated the Site or arranged
for the disposal of hazardous substances at the Site as those
terms are used in Section 107(a) of CERCLA, 42 U.S.C. § 107(a).
As a result, these companies, or in some cases individuals, are
liable under that section, and as such, responsible for
implementation of the remedy.
flR30t*990
-------
• A citizen asked if EPA's preferred remedy included deed
restrictions.
EPA Response: Yes. EPA has revised the preferred alternative to
include deed restrictions.
• A citizen asked if the actions conducted at the Site to date
are sufficient to maintain the status of the Site until the
remedial action begins.
EPA Response: Yes. Enough work has been completed under the
removal order to ensure minimal soil erosion and to sufficiently
stabilize the Site until the start of the Remedial Action.
Routine maintenance performed under the removal order assures
Site stabilization is maintained.
• Several commentors expressed concerns that the preferred
alternative did not totally address all the contamination from
the Site, specifically, the sediments in the tributaries of Rapp
Creek.
EPA Response: At the public meeting EPA had stated that it was
proposing to leave the sediment alone because the contamination
does not appear to be harming the ecosystem in the creek to a
great extent and because the sediments in the creek are sparse.
EPA stated that concentrations in the creek will likely go down
once the soil in the process area is capped. As sediments
migrate the contaminants are distributed and the concentrations
go down. There is an on-going debate whether to go in with
vacuums and possibly destroy the ecosystem, or to wait
considering the likelihood that concentrations will go down once
the sediments are no longer eroding into the creek. However
based on the comments received during the public comment period
and additional review and evaluation, EPA is now proposing to do
additional stream corridor sampling for mercury contamination,
the contaminant of most concern to the Fish and Wildlife Service,
(the agency EPA works with on natural resource issues). The
additional sampling will be used to verify the extent of Site-
related mercury contamination and to evaluate response options
for removing the mercury contaminated sediments from the stream
corridor. EPA's objective is to do as little harm as possible to
the creek system, because it is a high quality cold water
fishery. The decision to remediate the creek is being deferred
until this additional work is conducted and will be addressed in
a subsequent Record of Decision ("ROD").
• A citizen asked what would happen if EPA completes the
remedy and stops assessing the Site and the sediment
contamination is never addressed and resolved.
EPA Response: EPA will conduct long-term monitoring of this
Site, no matter which remedy is selected. EPA has mechanisms in
fiR30i*99l
-------
place to re-evaluate and make changes, if necessary/ to do what
is best for the environment and human health. In addition, EPA
has a five-year review period, at which time all elements of the
remedy are re-examined for effectiveness.
B. Ground Water Clean Up
• A citizen asked if it were possible that one of the test
wells may hit the aquifer that supplies his drinking water.
EPA Response: When the test wells are installed, the goal is to
intercept the aquifer or the water bearing zone, to test for
contaminants. Because ground water flows in specific directions,
the presence of a well on the Site, a mile and a half away, will
not affect any residential wells.
• A citizen asked how the contaminants are prevented from
leaking into the ground water when the test well is drilled and
whether the well is lined?
EPA Response: There are basically two ways to construct a
monitoring well. One is an open hole, similar to the way a
residential well is constructed. A hole is drilled, and because
the rock is hard, the well stays open. The fractures in the rock
carry the ground water into the well bore, where it is pumped
out. The second method is used in areas with a lot of fractures
at varying depths. In this case we want to sample a specific
water-bearing fracture. The well is drilled in the same way, but
we install either PVC pipe or stainless steel pipe with holes or
slats in the sides of the casing at the specific depth that we
want to monitor. The rest of the well borehole is cemented off.
Therefore, we do not cross-contaminate water by mixing it from
the surface down to the bottom.
• A citizen asked how deep were the monitoring wells at the
Site.
EPA Response: There are 11 wells on the Site which can be
divided into two groups. Half of them are less than one hundred
feet deep, and the other half are between one hundred and two
hundred feet deep. There is also a production well that is 350
feet deep.
• A citizen asked if organics were the only compounds tested
for in the wells.
EPA Response: EPA tested for what is called a target analyte
list and the target compound list. The target analyte list
includes metals and inorganics. The target compound list
includes volatiles, semi-volatiles, polycyclic aromatic
hydrocarbons ("PAHs"), and pesticides.
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• A citizen asked if the water would be discharged into the
stream.
EPA Response: Yes, the treated ground water will be discharged
into the west tributary of Rapp Creek.
• A citizen asked if it would be possible or desirable to pump
the discharge back into the ground water.
EPA Response: It would be possible to pump the discharge back
into the ground water. However, because the water is going to
end up in the creek naturally by the direction of the ground
water flow, it is not desirable to do so. We will be pumping the
water out of the well slightly faster than it would naturally
flow through the aquifer.
• A citizen asked if during the process of removing the
contaminants from the ground water, a citizen's well were to go
dry, would the citizen be responsible for redrilling the well.
EPA Response: If the event were caused by remediation of ground
water at the Site and EPA was conducting the remediation, EPA
would be responsible. If a PRP caused the event, the PRP would
be responsible for redrilling the well. However, as part of the
design process we identify the best place to drill the well to
capture the most amount of water without impacting nearby wells.
We conduct pump tests to calculate the size of the cone of
depression, where the capture zone is, and at what distance and
what direction water will flow to the well. The most critical
part of this process with regards to the potential for
residential wells drying out is the size of the capture zone.
Only the contaminated water is pumped and treated.
• A citizen asked if it were possible that quarry blasting in
the vicinity of the Site could cause ground water contamination.
EPA Response: The blasting could have an effect on the ground
water system only if the blasts caused large fractures that
extended all the way to the Site which is virtually impossible.
The blasting that is done at quarries is very limited.
Therefore, there is usually no damage to something far from the
source of the blasting.
• A citizen asked if EPA would test the water in nearby
residential wells periodically.
EPA Response: Long-term monitoring will include some off-site
residential sampling. The exact location of the residential
wells to be included in long-term monitoring will be addressed in
the remedial design work plan.
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C. Soil and Solid Waste Clean Up
• A citizen asked where the onsite contaminated soil was going
to be taken, specifically if it was going to be disposed of on
someone's private property.
EPA Response: One of the remedies includes offsite disposal for
the contaminated soils, but that was not EPA's chosen remedy.
These soils will be capped onsite. The proposed alternative does
include offsite disposal of solid waste. The waste will undergo
characterization and will be disposed of at an EPA-approved
facility.
• A citizen asked what is being done to control the erosion
outside the fenced area around the site.
EPA Response: The selected remedy will include regrading and
capping of the process area which is inside the fenced area, the
side slopes coming from this area will need to be stabilized in
order to ensure the integrity of the cap. Therefore these areas
outside the fenced area will be addressed in the remedial design.
• A citizen asked if the slurry walls would only be erected in
those areas illustrated on the Site map.
EPA Response: The slurry wall is only proposed in the area of
former collection basins AA and BB to provide containment of
soils containing semi-volatiles. Additional sampling will be
conducted during the Remedial Design Phase to more accurately
delineate exactly where the slurry wall will be constructed.
• A citizen asked for an explanation of the vacuum extraction
process.
EPA Response: During the extraction process, the soils remain in
place and air is forced through the soil by a vacuum. The air
that is pulled through the soil will cause the volatile organics
to vaporize. This air is then passed through a treatment system
to ensure there are no releases of organics into ambient air.
Carbon absorption canisters are the proposed treatment for the
recovered air stream.
• Will the exhaust gases from the vacuum extractor be tested?
EPA Response: Yes, exhaust gases will be monitored and tested to
ensure the continued effectiveness of -the carbon and to ensure
compliance with air requirements.
• A citizen asked how access to the process area and spray
field would be limited and if additional fences were going to be
erected.
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EPA Response: Access will be limited through the use of fencing
around these areas.
• A citizen asked if any soil sampling was conducted offsite.
EPA Response: Background samples were taken of the soil and
sediment offsite to establish the background quality of the soil
and sediment.
D. Potentially Responsible Party ("PRP") Issues
• A citizen asked if measures were being taken to pursue the
former owners and the parties responsible for the contamination,
rather than spending taxpayer dollars to clean up the Site.
EPA Response: The responsible parties have been conducting the
work and EPA has been overseeing that work. Therefore, only
limited Superfund monies have been used at this Site.
• A citizen asked how EPA was dealing with the PRPs who own
the Site.
EPA Response: At Superfund Sites, EPA has several options
available to deal with PRPs. One option is to place a Federal
lien on the property until past funds that were spent on Site
clean up are recovered. Before a Federal lien is placed on a
property, the owners of the property are entitled to a due
process hearing to determine whether EPA has the right to place
such a lien on the property. Another option is to pursue a cost
recovery action. This option is used when EPA is aware of
individuals or companies that are potentially responsible but are
not paying for the cleanup. EPA will then pursue those parties
for past costs. A third option would be issuance of an
administrative order which requires the PRP to conduct the remedy
at the Site.
• A citizen asked about the status of the individual
responsible for the contamination.
EPA Response: There is no single individual responsible for the
contamination at the Site, but rather, both individuals and
companies whom EPA believes are responsible for the
contamination. How EPA will deal with these individuals is at
present, enforcement confidential.
• A citizen asked if there were other measures that EPA could
use to recover money or punish those individuals responsible.
EPA Response: Superfund is a civil statute, not a criminal
statute. Therefore, we cannot take criminal action against
liable parties. We can pursue them only for contribution
to the cost of the remedy, conducting the remedy, or for past
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costs.
• A citizen asked if a lien has been placed against the Revere
property.
EPA Response: EPA has sent to the property owner notice of its
intent to file a lien. The property owner has requested a due
process hearing. That hearing has not, as of yet, been
scheduled.
• A citizen asked if Harbucks were in any way responsible and
if not, if the company would be able to make a profit on the
property after the remediation is completed.
EPA Response: Under Section 107(a) of CERCLA, 42 U.S.C.
§ 107(a), Harbucks is a liable party since they are the current
owner of the property. EPA does not have sufficient information
with regard to the value of the property to make an informed
decision as to whether Harbucks would realize a profit if they
sold the Site following remediation.
• A citizen asked if the value of property would be considered
in an individual's net worth when the financial viability is
calculated.
EPA Response: When EPA notices PRPs, they are asked for a good
faith offer to design and implement the remedy. One of the
requirements is that a PRP prove that it is financially able to
conduct the work. They also are required to provide proof of
insurance and numerous other financial assurances. The decision
of whether to include the value of the property into an
evaluation of the company's net worth is an enforcement
confidential matter.
E. Superfund Process
• A citizen asked if the Township could have a copy of the
maps illustrating the locations of the ground water wells that
tested positive for contamination, the map illustrating the
proposed cap area, and the map of the proposed soil remediation
areas.
EPA Response: All of these maps are in the RI documents which
are part of the Administrative Record. The Township Building is
one of the Administrative Record repositories so these documents
are easily accessible to the public.
• A citizen asked if, after the clean-up process began, the
community and the Township would continue receiving updates on
the status of the Site.
EPA Response: Yes, EPA will continue to inform the community
flR3Ql»996
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using fact sheets, public meetings, and direct phone calls to
Township supervisors and officials.
• A citizen asked what the process was after the public
comment period ended.
EPA Response: The next step will be to prepare a responsiveness
summary using the transcript from the Proposed Plan public
meeting and all additional information. EPA takes all comments,
questions, letters, and the public meeting transcript, and
responds to all substantive issues in this formal document.
Then, EPA prepares the ROD after deciding which alternative will
be implemented. The ROD is signed by the Regional Administrator
and will be placed in the Site repositories once signed. EPA
will run a public notice announcing the ROD has been signed and
is available to the public.
• A citizen asked if the next step is to design the remedy and
who would be designing the remedy.
EPA Response: After the ROD is signed, EPA will issue special
notice letters to the PRPs inviting them to implement the
Remedial Design and Remedial Action. Once these letters are
issued it triggers a 120-day moratorium period during which the
parties may negotiate with EPA to conduct the remedy. If the
parties agree to do the work, they enter in to a Consent Decree.
A Consent Decree is a document entered by the court which
outlines all the requirements for implementing the Remedial
Design and Remedial Action by specifying when the work plans are
due as well as other critical deadlines.
• A citizen asked if after the Consent Decree is entered the
next step is to locate a contractor.
EPA Response: If a cleanup is being performed by the responsible
parties, those parties seek a contractor. The responsible
parties are then required to notify EPA, usually within 15 days
of the effective date of the consent decree, of the contractor's
qualifications and experience for EPA acceptance. Then, the
contractor usually has 45 days to submit the work plan for the
Remedial Design. This work plan will set forth schedules for
delivering any required samples to successfully design the
systems that are required for remediation.
• A citizen asked if it would be six or eight months until the
actual work begins, based on the schedules outlined in the
Consent Decree.
EPA Response: It could be even longer. First, the Remedial
Design must be completed. Then, the Remedial Action begins, when
the actual work on the Site is performed. The actual work will
likely not begin for at least one year pending review and
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approval of the design documents.
• A citizen asked if it would have been possible to notify the
Township officials well in advance of the public meeting to
better schedule the meeting and ensure that the Township was well
informed.
EPA Response: EPA has been in constant communications with the
Township, including discussions on the best location for the
public meeting and what time to hold the meeting. By law, EPA is
bound to hold the meeting within the thirty-day public comment
period.
• A citizen asked what event triggered the thirty-day public
comment period.
EPA Response: The release of the Proposed Plan.
• A citizen asked if it would have been possible to postpone
the release of the Proposed Plan.
EPA Response: EPA attended a Township meeting in April during
which it notified the Township that the Proposed Plan would be
issued in the summer. EPA made every attempt to ensure that
interested members of the community received a copy of the
Proposed Plan and had ample time to prepare for and attend the
public meeting. These events have not been a surprise, they have
been carefully planned. Therefore, it would have been possible,
but not desirable, to postpone the Proposed Plan.
• A citizen asked if there were procedures in place to notify
local communities of Superfund sites in their area, and how often
the National Priority List ("NFL") is updated.
EPA Response: EPA has requirements, under the Resource
Conservation and Recovery Act ("RCRA") to track and regulate
hazardous waste production and disposal. The NPL list is still
growing as new sites are identified and classified as Superfund
sites. Generally, EPA does not specifically go to each local
township and municipality and notify them that there is
potentially a Superfund site in their jurisdiction. When a site
is proposed for the National Priorities List, it is published in
the Federal Register. When the site is officially listed, more
extensive community outreach is conducted by placing public
notices in the newspaper, sending out fact sheets, and holding
public meetings. However, most communities are well aware of a
problem before EPA adds a site to the NPL. Often, EPA is
informed of the problem by community officials.
F. Future Site Usage
• Several citizens asked what kind of uses the property will
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10
have after the remedy has been implemented. For example, could
it be used as a golf course or a quarry?
EPA Response: Due to the nature of the cap, the areas of the
property that are capped will be restricted. Anything that would
breach the integrity of the cap would be an unsatisfactory use of
the area. The areas of the property not capped will be without
restrictions. The main restriction on the usage of the land will
prohibit such activities as excavation or installation of wells.
Additionally, there will not be any use of ground water from
within the capped area. A golf course could be built but the
ground water could not be used to irrigate the property. Also a
quarry could not be implemented at the location of the cap
because it would likely damage the cap. However, it is possible
to have a quarry in another section of the property where it
would not damage the cap. The presence of the cap limits the
future use of the Site which will be controlled to a certain
extent by deed restrictions. Site use outside the area of
contamination will be the jurisdiction of the Township which
handles zoning matters. Therefore, the property owner must
confer with local officials, and most likely, apply for a zoning
permit in order to change the current use of the land.
• Will the land be able to be productively used within a
couple years?
EPA Response: The presence of the cap and the corresponding deed
restrictions limit the future use of the Site; however, there can
be productive uses within these limits.
PART II; SUMMARY OF WRITTEN COMMENTS RECEIVED AND EPA78
RESPONSES
These comments or questions were received at the August 12, 1993
public meeting or by mail during the public comment period, and
may have been covered generally in Part I of this Responsiveness
Summary. Concerns and questions presented in this section were
placed into the following categories:
Copies of all written comments received are contained in the
Administrative Record for the Site. The written comments and
EPA's responses are summarized below:
PRP Comments: In a 20-page document dated September 24, 1993
the Revere Steering Committee ("RSC") comprised of AT&T
Technologies, Inc., Carpenter Technologies Corporation, GTE_
Products Corporation, IBM Corporation, NCR Corporation, Square D
Corporation, and Unisys Corporation commented on the Proposed
Plan for the Site. Substantive comments and concerns and EPA's
responses are summarized below.
ftR30k999
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RSC comment #1: The RSC stated they were disturbed by EPA's
denial of the RSC's request for a 45-day extension to the public
comment period while extending the comment period to newly
identified and recalcitrant PRPs. The RSC states that EPA's
motives in the initial denial of their request was due to the
Agencies desire to issue a ROD by the end of the fiscal year in
order to achieve an end of year goal.
EPA response: EPA denied the RSC committee request for an
extension to the public comment period due to the untimeliness of
the request. The RSC conducted the RI/FS at the Site. EPA
selected a Proposed Remedial Alternative from the alternatives
presented in the RSC's RI/FS report. EPA's selection was based
on information with which the RSC was intimately involved, and
therefore, the RSC was knowledgeable of the Site as well as the
alternatives that were evaluated.
• RSC comment #2: The committee believes the proposed remedy
results in the unnecessary expenditure of at least $3,000,000
instead of selecting the alternative preferred by the RSC.
EPA Response: EPA disagrees that the additional expenditure is
unnecessary. Under the NCP, EPA uses nine criteria of
evaluation. EPA is required to select an alternative that
attains ARARs if an action is warranted. Action is required
where there is an unacceptable risk. Based on the risk
assessment conducted for this Site/ exposure to contaminants in
the soil at the Site represents an unacceptable risk. In this
case, the soil erosion control cap preferred by the RSC will not
meet the threshold criteria of attaining all ARARs. Alternative
S6 is protective of human health and the environment and attains
all ARARs.
• RSC comment #3: The committee believes that the
Pennsylvania ARAR which requires that the ground water be
remediated to background levels is neither applicable,
appropriate nor relevant. The committee believes that if EPA
concludes that remediation to background is an ARAR, EPA should
waive this ARAR based on technical impracticability.
EPA Response: The Commonwealth of Pennsylvania has asserted an
ARAR for this Site requiring that all ground water must be
remediated to "background quality". The specific citations for
this ARAR include 25 PA code 264.90 - 264.100, and in particular,
25 PA code 264.97(i),(j), and 264.100 (a)(9). EPA has recognized
this as a relevant and appropriate requirement for ground water
remedial action at the Revere Chemical Site. Sufficient evidence
does not exist to waive this ARAR based on technical
impracticability. Nor does sufficient evidence exist to
demonstrate that a combination of natural attenuation and
institutional controls is a feasible remedial action alternative.
Due to the need for additional information, EPA has decided to
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defer the selection of a ground water remedy until additional
data is gathered. The goal of this additional hydrogeologic
investigation is to provide information on the practicability of
actively pumping ground water to achieve background cleanup
levels. This data will be compared to information previously
gathered to determine the rate of natural attenuation after the
Organic Hot Spots have been remediated.
• RSC comment #4: Since EPA must consider the cost
effectiveness of a remedy, the Pennsylvania background
requirement would substantially increase costs, and since cleanup
to MCLs is protective of public health and the environment, the
Pennsylvania background requirement should not be considered an
ARAR.
EPA Response: EPA disagrees. Attainment of ARARs is a "threshold
requirement" as is the requirement that the remedies be
protective of human health and the environment. See 40 CFR
§300.430 (e)(2)(iii). ARARs have to be met by the selected
remedy, even if it is not necessary to ensure protectiveness. If
a requirement is applicable or relevant and appropriate, it must
be met unless one of the six waivers applies. ARARs represent
the minimum cleanup level that a selected remedy must attain.
EPA has determined that the Pennsylvania cleanup to background is
relevant and appropriate to ground water remediation. However,
EPA is presently deferring the ground water remedy until
additional data is gathered to make this determination.
• RSC comment #5: EPA should waive the Pennsylvania "ARAR"
because it has not been consistently applied or has been variably
applied and inconsistently enforced in similar circumstances at
other remedial actions within the State.
Inconsistent application of the Pennsylvania Requirement has
occurred both by EPA and PADER. For example, the RODs for the
Reeser's Landfill Site, Henderson Road Site, Craig Farm Dump,
Strassburg Landfill, Cryo-Chem and Osborne Landfill did not
require the restoration of ground water to "background " levels,
even though at some of these sites there is low level
contamination of the drinking water aquifer.
EPA Response: EPA must consider each site on a case-by-case
basis when issuing a ROD. EPA considers in detail the nine
balancing criteria and other factors, such as site-specific risk
factors, site conditions, the amount of waste to be treated, etc.
The fact that EPA did not require cleanup to background levels at
six other sites where a drinking water aquifer has been
contaminated at low levels out of the many RODs signed by EPA is
not conclusive evidence that EPA has been inconsistent in its
application of ARARs.
• RSC comment #6: The cost of installing a clay cap is
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significantly more than the additional cost to achieve the
necessary VOC concentration for a soil erosion cap. Moveover,
CERCLA prefers treatment over encapsulation and therefore, the
soil cap should be the preferred choice.
EPA Response: Insitu vacuum extraction is a component of both
Alternative S3 (Soil Erosion Cap) and Alternative S6 ( Clay Cap).
As outlined in the ROD, the cleanup level for VOCs in soil will
be based on the performance of the VOC system rather than a
cleanup level based on the permeability of the cap as presented
in the RSC's FS Report. Therefore, both remedies would require
the same level of treatment for the VOC-contaminated soils and
hence, there would be no cost difference for this component of
Alternative S3 and S6. Alternative S6 is not encapsulation as
stated in the comment. EPA has determined that the landfill
closure requirements set forth in the Residual Waste Regulations
at 25 PA Code §§ 288.234, 288.436 and Appendix A Table II are
relevant and appropriate for any actions which include capping.
The soil erosion control cap preferred by the RSC does not meet
the requirements of these regulations.
« RSC comment #7: There is no scientific data to support the
need for a clay cap as opposed to a soil erosion cap relative to
the potential for migration of metals from the soil.
EPA response: EPA is mandated by CERCLA to select remedies
that attain all ARARS. The soil erosion cap does not meet the
threshold criteria.
• RSC comment #8: The Site possesses the characteristics
which make a source control-natural attenuation remedial strategy
for ground water appropriate and, indeed, preferable. At the
present time, the contamination is limited, an adequate
monitoring system can be designed, source remediation for VOCs is
proposed, there are no receptors at risk and the characteristics
of the contaminants are suitable for natural attenuation and
degradation.
EPA Response: EPA is not convinced that natural attenuation is
preferable even when there are no current receptors to the
contaminated ground water. Remediation of the VOC-contaminated
soils along with pumping of the contaminated ground water is
consistent with CERCLAs preference for treatment. However,
sufficient evidence does not exist to waive this ARAR based on
technical impracticability. In addition, sufficient evidence
does not exist to demonstrate that a combination of natural
attenuation and institutional controls is the only feasible
remedial action alternative. EPA has decided, therefore, to
defer the selection of a ground water remedy until additional
data is gathered.
• RSC comment #9: The cost for each alternative is derived
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from the FS Report. Soil and ground water remedial assessments
were made on the basis of protecting ground water to MCL levels,
not "background". Therefore, these costs are not accurate if
PADER's policy of "background" is enforced.
EPA Response: The costs for ground water remediation were
developed using a 30-year O&M period which is the typical time
frame used by EPA for estimating ground water cleanup costs. The
costs projected for maintaining the insitu vacuum extraction
system were estimated assuming that the 22.8 mg/kg cleanup level
proposed by the RSC would be attained in 11 months. EPA agrees
that the costs associated with the operation and maintenance of
the VE system are not accurate and will increase in proportion to
the length of time the system is operated. EPA has stated in the
ROD that all costs, time frames and waste/treatment volumes are
estimates and the Present Worth estimates may vary depending on
the actual duration of the Remedial Action field activities.
• RSC comment #10: The Plan fails to acknowledge as part of
the Site history, the extensive removal action and sedimentation
and erosion control measures implemented by the RSC to comply
with the 1991 Administrative Order For Removal Response
Activities.
EPA Response: EPA agrees. EPA has included this information in
the ROD.
• RSC comment #11: "The results of the soil investigation
conducted during the RI identified ten metals: antimony, arsenic,
beryllium, cadmium, chromium, copper, lead, mercury, vanadium and
zinc, all of which are present in Site soils at concentrations
statistically distinguishable from background." The preceding
statement is not accurate. For example, during the background
sampling for mercury, only one sample contained detectable levels
of mercury. Therefore, and as indicated in the Feasibility
Study, there is insufficient data to derive any statistical
analysis for mercury. Also, arsenic and zinc are not
statistically distinguishable from background.
EPA Response: The statement was taken verbatim as it appears on
page 1-9 and also on page 1-13 of the FS which was prepared by
the RSC consultants. The RSC refers to Figure 6-11A, note 5 of
the RSC's RI Report where it states, "Because mercury was not
detected in the background soil samples, each sample that had
detectable concentrations of mercury was considered statistically
distinguishable." As stated by the commentor the data was
insufficient to derive a statistical background number for
mercury. However, the absence of mercury in the background
samples demonstrates that mercury present in Site soils is due to
Site related activities, is a Site contaminant of concern, and is
therefore distinguishable from background. With regard to
arsenic concentrations, on page 6-21 of the RSC's RI Report, it
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states that arsenic concentrations are statistically
distinguishable from background. With regard to zinc, on page 6-
25 of the RSC's Rl Report, it states zinc is statistically
distinguishable. Therefore, any inaccuracies in that statement
are as a result of inaccurate conclusions drawn in the RI and FS
Reports submitted by the RSC. EPA has revised the statement by
deleting the word statistically.
• RSC comment #12: Has EPA received approval from PADER
regarding the design of the cap as described in the Plan?
EPA Response: No. The dimensions stated in the Proposed Plan
were used to develop cost estimates. The actual clay cap to be
installed will comply with the design requirements of the
Pennsylvania regulations.
• RSC comment #13: None of the ground water alternatives in
the FS Report include costs for additional pre-design or design
investigations. The RI Report concluded that the extent of
ground water contamination at the Site had been defined.
The Proposed Plan stated: "However, the actual number and
location of extraction wells will be determined following
additional hydrogeologic characterization that will be conducted
in the remedial design phase."
EPA Response: The cost of the ground water extraction option
needs to include funds for a design study, including long-term
pump tests on up to four wells. This is needed to define the
capture zones of the extraction wells. This type of additional
hydrogeologic characterization is typically conducted during the
remedial design phase.
• RSC Comment #14: "Based on current information, this
alternative would appear to provide the best balance of trade-
offs among the alternatives with respect to the nine criteria the
EPA uses to evaluate each alternative." The RSC states that the
preceding statement in the Proposed Plan is not accurate as
evidenced by the statements in the Comparative Analysis of
Alternatives Section of the Proposed Plan which indicate that
Alternative S3 provides the same level of performance relative to
the NCP criteria as Alternative S6.
EPA Response: EPA disagrees. Alternative S3 does not provide
the best balance of trade-offs among the alternatives with
respect to the nine criteria because it does not comply with
ARARs. EPA has identified the Residual Waste Regulations as
ARARs for the Site. Under the Compliance with ARARS section in
the Proposed Plan, however, EPA incorrectly stated that
"Alternative 2 through 9 can be designed, constructed and
operated to meet with all appropriate requirements." That
statement was incorrect. As stated in the ROD, Alternatives S3,
S7, S8 and S9 would not attain the closure requirements for a
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landfill under the Pennsylvania Residual Waste Regulations for
the permeability of the cap.
• RSC comment #15: ".., EPA believes the preferred
alternative would protect human health and the environment, would
comply with ARARs and be cost-effective." As evidenced by the
statements from the Plan for each of the evaluation criteria,
Alternative S6 does not provide any advantages and is more costly
than Alternative S3. Therefore, this statement is not accurate
relative to being "cost-effective".
EPA Response: See previous response. Noting the correction to
the statement regarding compliance with ARARs, this statement is
accurate with regard to Alternative S6 being cost-effective when
compared to the other Alternatives which would comply with all
ARARs.
PRP Comments: In an 11-page document, General Electric Company
commented on the Proposed Plan for the Site. Substantive
comments and concerns and EPA's responses are summarized below.
• GE Comment #1: Alternative S2 in the Proposed Plan together
with institutional controls like those described in Alternative
GW-2 would satisfy all the objectives identified in the Proposed
Plan and would permit all ARARs to be achieved. While GE
questions whether the Pennsylvania ARARs relied upon by EPA in
selecting the remedy are ARARs, GE believes the ARARs could be
satisfied now based on a review of Site conditions. In any
event, there is not evidence in the RI Report that background
concentrations at the edge of the waste management area could not
be achieved with Alternative 2. GE further states that data from
MW-9, MW-10, and MW-11 provide additional reason to question an
assumption that the regulations would be triggered.
EPA Response: In regard to the Pennsylvania ARARs, see response
to RSC comment #2. Although the "primary objectives" of the
remedy as stated in the Proposed Plan may be met by Alternative
2, EPA disagrees with the statement that the ARARs could be
satisfied with Alternatives 2 and GW-2. Section 121(d)(2)(A) of
CERCLA requires that the selected remedy comply with or attain
the level of any applicable or relevant and appropriate
requirements of federal or State environmental laws. As stated
previously, a soil erosion cap would not comply with the
standards for a cap and cover required by 25 PA Code §§ 288.234,
288.436 and Appendix A Table II. Alternative 2 is rejected
because it does not meet the threshold criteria.
Presuming the commentor defines the edge of the waste management
area as the area to be capped, EPA agrees that the RI does not
contain evidence that background concentrations could not be
achieved. Monitoring wells do not exist in these locations.
In addition MW-9, MW-10 and MW-11 are screened in a separate
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deeper aquifer than the contaminated wells and therefore, are not
in downgradient positions from the contaminated wells.
Therefore, the comment that ARARs for ground water would not be
triggered is irrelevant since these are not monitoring the
"known" contaminated aquifer.
• GE comment #2: All unacceptable risks to health and the
environment would be eliminated by an engineered soil cap and
institutional controls required to preserve the integrity of the
cap. The Baseline Risk Assessment shows that even if no remedy
were implemented, the Revere Site presents minimal risks. Table
1 of the Proposed Plan shows that for the four current use
scenarios considered, even the greatest risk as shown on Table 1
was well within the range of acceptable levels. Table 1 shows
non-cancer hazard quotients of 2.9 to 2.95. These are slightly
above the hazard index of 1, where "there may be a concern for
potential non-carcinogenic effects." The quotient exceeds 1 only
because of an assumption of inhalation of chromium. However, the
Proposed Plan acknowledges that the chromium risk is probably
overstated and thus leads to the conclusion that EPA's concern is
also overstated. Accordingly, there is a substantial question as
to whether the Site represents any unacceptable risks given
current uses.
EPA Response: The assumptions regarding inhalation represent a
default scenario for reasonable maximum exposure. This scenario,
which is less than worst-case, is EPA's estimate of the highest
exposure that an actual individual would be likely to receive.
The PRPs have not presented any data specific to the Site that
suggest some lower exposure would be more appropriate.
Therefore, EPA believes that the inhalation risk assessment is
protective of public health, while not being unreasonably
pessimistic. Because the estimate is a reasonable maximum, most
individuals would have lower inhalation exposure and lower risk.
If the chromium concentration detected in the soil were known to
be trivalent chromium, the health risk estimate would have been
considerably lower. However, the PRPs have not provided EPA with
data which distinguish between trivalent and hexavalent chromium.
Since the ratio of the two chromium species is unknown, EPA must
make the protective assumption that all chromium is hexavalent.
This is acknowledged as a significant uncertainty in the risk
assessment, but EPA has chosen, as a matter of national policy,
to give the benefit of such uncertainties to protection of the
public health and the environment and not the PRPs.
• GE Comment #3: The Baseline Risk Assessment ("BRA")
estimates somewhat greater risks for a hypothetical onsite
resident. However, the Risk Assessment does not provide any
basis for assuming residential development. In fact, it
specifically refers to this scenario as "hypothetical" because
future use had not been considered. BRA at N-28.
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Both the NCP and EPA Guidance prohibit such an assumption and
require that exposure scenarios be reasonable based on site-
specific evidence. The Preamble to the NCP states:
An assumption of future residential land use may not be
justifiable if the probability that the Site will support
residential use in the future is small.
EPA may not conclude that such a probability is more than "small"
without site-specific evidence. There is nothing in the Risk
Assessment supporting the hypothetical assumption of future
residential use. Therefore, risks premised on it should not be
considered.
EPA Response: EPA Region III places the burden of documenting
non-residential future use on the PRPs. As with the inhalation
and chromium species issues, EPA gives the benefit of the
uncertainty to protection of the public and the environment, not
the PRPs.
In order for EPA to determine that the probability of residential
use is small, the risk assessment must contain a detailed
discussion of population trends, current zoning, development
plans of local authorities, current use restrictions on nearby
properties (e.g., state parks, gamelands, etc.), and other
appropriate site-specific factors. The risk assessment did not
contain this information, and EPA is not aware of any
characteristics of the Site (other than its NPL status) that make
residential development unlikely. The argument that residential
use is unlikely because the Site is contaminated, and therefore,
does not need to be cleaned, is not sufficient.
• GE Comment #4: The Pennsylvania regulations with respect to
attaining background concentrations are not ARARs.
First, they are not relevant and appropriate until there is
evidence that a monitoring well located at or beyond the
downgradient edge of the process area — "the "waste management
area" here — would show concentrations of VOCs or TCB above
background.
Second, the regulations do not require all contaminated ground
water to be restored to background, only that background be
achieved at the downgradient monitoring points.
Third, under the NCP, relevant and appropriate standards are
those that are well-suited to the circumstances at the particular
site under review. A requirement that ground water be restored
to background concentrations without regard to whether or not the
ground water will ever be used cannot be considered relevant and
appropriate.
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EPA Response: EPA disagrees. EPA has determined that the
Pennsylvania regulations are relevant and appropriate. The
trigger for this requirement is that ground water has been
contaminated above drinking water standards.
EPA disagrees that only background levels be achieved at the
downgradient monitoring points (outside the area to be capped).
If waste is left in place, the area of attainment is the area of
the plume, excluding the waste management unit. Although there
are no waste management units remaining on the Site, source areas
for ground water contamination are defined as the Organic Hot
Spots. Wells that are placed downgradient of these Organic Hot
Spots are contaminated and are in the "area of attainment" for
ground water remediation even though this area encompasses an
area of the Site to be capped. Moreover to state that absent
evidence of contamination at downgradient monitoring points,
ARARs are not triggered is contrary to the letter and spirit of
CERCLA cleanups. CERCLA is concerned not only with cleaning up
the contaminated ground water that escapes from a Site, but also
in cleaning up the ground water onsite. Since there is ample
evidence to show there is ground water contamination onsite then
ARARs are triggered. However, as stated above, EPA has chosen to
defer making a decision with respect to ground water until
further data has been gathered.
• The Township supervisors and the Township Engineer wrote to
suggest that all contaminated sediment be removed from the onsite
tributaries as part of the Remedial Action.
EPA Response: The Proposed Plan did not address remediation of
the stream sediment. Based on comments received, EPA is
requiring additional sampling of the stream corridor to define
the extent of mercury contaminated sediment and an evaluation of
alternatives for addressing removal of mercury contaminated
sediments.
• The Township supervisors wrote asking for the actual
proposal regarding that portion of the preferred alternative
which limits access to the process area and spray fields and
requires long-term monitoring and a 5-year review program.
EPA Response: Fencing will be used to limit access to the capped
areas of the spray fields and the process area. Section IX, The
Selected Remedy and Performance Standards, specifies the
requirements for long-term monitoring and the five year review.
• The Township supervisors wrote asking about the proposed
steps for the protection of endangered species on the Site. The
letter indicated that the Township is aware of at least one plant
that is under consideration for endangered species protection on
the Site.
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EPA Response: The law requires that if it is determined that the
remedy will adversely impact endangered species or sensitive
habitats that steps are taken to mitigate those impacts. The
selected remedy may impact the wetland area in the South Spray
field. During design, EPA will evaluate those impacts and
options for addressing risks posed by the contamination.
• Township comments: Comments were made at the meeting by the
area residents and Township which indicated there may be offsite
areas contaminated by air-borne effluent (while being sprayed)
and/or overland runoff when the Site was in operation. The EPA
representative indicated that EPA would do a site inspection of
these areas with a Township representative and/or a resident who
is knowledgeable of these areas. Following the inspection and
additional review of previously completed soils testing, it is
our understanding that remediation of offsite areas may be
included in the final plan if deemed warranted by EPA.
EPA Response: The EPA Remedial Project Manager contacted the
resident who indicated he knew where these offsite areas are
located. He did not make himself available to EPA officials.
Township representatives were not aware of these alleged offsite
contaminated areas. However if new information were to indicate
that contamination related to this Site exists in offsite areas,
EPA would take steps toward remediation.
B. Ground Water Clean Up
• The Township supervisors asked for a written proposal of the
plan to protect the neighboring wells and asked which neighboring
residential wells would be monitored in conjunction with the
Remedial Action.
EPA Response: These issues will be addressed in the remedial
design work plan. When the work plan is approved it will be
placed in the Site repository which is located at the Township
building.
• The Township supervisors asked for a written proposal
addressing the final discharge of treated ground water to the
stream before the start of the Remedial Action plan. The
Township is concerned that this discharge could disturb
contaminated sediment and cause the spread of the contamination
downstream.
EPA Response: In response to public comments, EPA has decided to
defer the ground water remedy until additional data is gathered.
This issue will therefore, be addressed in OU-2. The preferred
alternative for OU-2 will be required to meet the substantive
requirements of the National Pollution Discharge Elimation System
(NPDES) which sets limits for discharges to all surface waters.
This information will be included in the remedial design for the
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Site, a copy of which will be placed in the Administrative Record
for the Site which is located at the Township building.
• The Township Engineer wrote asking that Mr. and Mrs. Nick
Cutaneo receive the test results from previous well water samples
sent to them.
EPA Response: The test results for the Cutaneo's well water were
sent to Mr. Cutaneo on September 1, 1993.
• The Township Engineer wrote asking that wells on all
adjacent properties be included in EPA's long-term monitoring,
with results being sent to the property owners on a regular
basis.
EPA Response: EPA will determine which wells will be included in
long-term monitoring during the remedial design phase. EPA will
send test results to the residents following receipt and
evaluation of the analytical data.
C. Soil and Solid Waste Clean Up
• The Township supervisors and the Township Engineer wrote
asking that the silt fence be installed along the entire length
(both sides) of the two tributaries which traverse the Site
property.
EPA Response: EPA will evaluate the need for additional silt
fencing.
D. Superfund Process
• The Township supervisors wrote asking that any future
updates regarding Revere or any other Site in Nockamixon Township
be shared with the Township officials as soon as possible,
including updates or additions to the CERCLIS list.
EPA Response: The Township currently receives copies of the
monthly progress report which are submitted to EPA by the
consultants for the RSC. EPA will continue to have copies of
Progress Reports sent directly to the Township. In addition the
Township receives copies of any Fact Sheets that are prepared for
the Site. With respect to the updates and additions to the
CERCLIS List. Updates to this list are made on a biweekly basis.
Currently, EPA does not notifying individual townships and
municipalities when a site is listed on the CERCLIS. EPA does
not have the resources to do this every time the list is updated.
However the Township can periodically request the information
which is specific to their area by writing the FOIA coordinator
and requesting all sites on the list within their geographic
area.
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• The Township Engineer wrote requesting that EPA hold an
additional public meeting just prior to the start of construction
activities at the Site.
EPA Response: EPA routinely holds public meetings at critical
milestones in the cleanup process. EPA will comply with this
request.
• The Township Engineer wrote requesting that the Township
supervisors be notified in writing of all important dates and
deadlines in the remediation selection/implementation procedure.
EPA Response: The Township currently receives copies of the
monthly progress report which are submitted to EPA by the
consultants for the RSC. EPA will continue to have copies of
Progress Reports sent to the township.
E. Future Site Usage
• The current owner of the Site property wrote objecting to
EPA's remedy, specifically as it minimizes future usage of the
Site.
EPA's Response: Each of the remedies evaluated for mitigating
risk posed by this Site would minimize future usage of the Site
to some degree. It is not uncommon for Superfund Sites to have
restrictions on future use as a result of a cap being a component
of the remedy. EPA's goal is to select remedial actions that
protect human health and the environment, that maintain
protection over time, and that minimize untreated waste. This
goal reflects CERCLAs preference for achieving protection through
the use of treatment to the maximum extent practicable. In
addition EPA is required to select remedies that are cost-
effective. The cap is a cost-effective way to mitigate the
threats to human health, and the environment posed by the
inorganic contamination of the soil at the Site.
• State Comments: The Proposed Plan shows the calculated
risks for beryllium, PAHs, and PCBs but does not include
chromium, lead, arsenic and other significant site-related
contaminants. Significant concentrations of other site-related
contaminants should be included in the risk assessment for the
site because of the cumulative effects of these substances.
EPA Response: Significant concentrations of site-related
contaminants was included in the risk assessment. Table I of the
Proposed Plan identified those chemicals associated with the
majority of the risk.
• State Comment: The Proposed Plan should state how access to
the process area and spray fields will be limited.
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EPA Response: As stated in the ROD, fencing will be used to
limit access in these areas.
• State Comment: The permeability/infiltration rate of the
caps proposed as alternatives should be given in the Proposed
Plan.
EPA Response: The Proposed Plan summarizes information presented
in the RI/FS Reports. As such, that level of detail was not
presented but can be found in the FS document.
• State Comment: The operation and maintenance requirements
of the slurry wall are not given in the Proposed Plan. This may
have a bearing on the long-term effectiveness and permanence of
this part of the proposed remedy.
EPA Response: O&M requirements of the slurry wall will be
addressed as part of the remedial design process. As stated in
the ROD, a post-construction maintenance plan shall be developed
to maintain the integrity and effectiveness of the slurry wall,
including making repairs to the slurry wall as necessary.
• State Comment: The discussion of long-term effectiveness and
permanence contained in the Proposed Plan does not adequately
address this criterion.
EPA Response: Although not specifically outlined in the Proposed
Plan, EPA believes this has been adequately addressed in the
Summary of the Comparative Analysis of Alternatives Section of
the ROD.
• State Comment: According to the RI/FS report, there exists
the potential for buried drums to be located in the vicinity of
lagoon C. The Proposed Plan does not address the possibility of
investigating the Site for additional buried drums, or how such
areas would be remediated.
EPA Response: EPA disagrees. On page 7 of the Proposed Plan,
EPA discusses the possibility of buried drums in the vicinity of
former Lagoon C. Each alternative except Alternative 1 includes
a component which addresses the excavation and ultimate disposal
of any such drums.
• State Comment: The statement that permanent disposal options
would be utilized to the maximum extent practicable is not
supported by the comparative analysis of alternatives since there
is no discussion as to why offsite disposal was eliminated during
the selection process. It should also be noted that CERCLA
Section 121 (b)(1) mandates that remedial actions be selected
that are: 1) protective of human health and the environment, 2)
cost effective, and 3) utilize permanent solutions and treatment
technologies to the maximum extent practicable. However, the
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remedy proposed involves treatment methods to contain the
contaminated soils onsite (i.e. slurry wall and capping), not to
permanently remediate them.
EPA Response: The Proposed Plan describes the remedial options
that were considered in detail in the RI/FS Report. Off-site
disposal of all the contaminated soils is a process option that
was screened out prior to the development and preliminary
screening of alternatives. Therefore, it is not appropriate to
discuss that option in the comparative analysis of the Proposed
Plan. As stated on page 1 of the Proposed Plan, the Proposed
Plan is not a substitute for the RI/FS which is the primary
source of detailed information on the process options and
remedial alternatives analyzed for addressing the Site.
As stated in the ROD, Alternative S6 does involve treatment of
the principal threats (i.e. VOC-contaminated soils) posed by the
Site. EPA believes Alternative S6 is protective of human health
and the environment, is cost-effective and utilizes permanent
solutions and treatment technologies.
• State Comment: Although a cap may be placed over the soils
to prevent surface water from eroding the soils and carrying
contaminants from the Site directly into adjacent streams,
movement of groundwater from below into the buried contaminated
soils can still transport contaminants to the streams and to
other parts of the ground water aquifer. A cap will reduce the
infiltration rate of water through the soils, but water can still
penetrate down through the soils, and cause the migration of
contaminants that are left in the soils.
EPA Response: EPA does not disagree. However Site data
indicates that the metals are not impacting ground water above
MCLs. As stated in the draft ROD, the seeps from the shallow
aquifer which discharge to the stream will be included in long-
term monitoring of the Site. Therefore, the cap is an effective
means of mitigating the risks posed by the Site. In addition the
ROD calls for treatment of VOC-contaminated soils to levels that
will not impact ground water above drinking water standards. For
the trichlorobenzene ("TCB") Organic Hot Spots which are not
amenable to VE, the slurry wall and the clay cap will provide an
effective means of isolating the TCB Organic Hot Spots from
contact with the ground water in the overburden.
• State Comment: Under the "To Be Considered" section, it is
incorrectly stated that the remedy for the site will comply with
the applicable portions of the PADER Groundwater Quality
Protection Strategy. This has not been demonstrated in the ROD.
In our previous comment letter, we discussed the application of
the Groundwater Quality Protection Strategy and the use of MDLs
to back-calculate contaminant levels remaining in soils that
would not impact groundwater above background levels. Although
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the Department has strongly recommended the use of MDLs in
calculating cleanup levels, and provided information on site
contaminant MDLs, the use of MDLs has not been incorporated into
the ROD.
EPA Response: EPA disagrees. In the Department's letter of
September 21, 1993 the following was stated, "Two options appear
reasonable to the Department: 1) Contaminated soils onsite
should be remediated so that the cap is only needed for the
limited areas (process basins and spray fields) currently
proposed, or 2) The cap should be extended over all areas where
soils contain leachable contaminants above MDLs. In either case
the remedy should include a provision for a ground water
monitoring program at the site." EPA has incorporated the use of
MDLs into the ROD to define the areal extent of the cap. In
Section IX.A.4.A. Construction of Cap. The ROD states the
following "The cap shall be constructed in the areas where the
soils exceed any of the following criteria: the hazard index for
exposure to contaminated soils exceeds 1; exposure to
contaminated soils represents a carcinogenic risk greater than 1
x 10~4; or when using the Synthetic Precipitation Leaching
Procedure, listed as EPA method 1312, the soils contain leachable
contaminants that will leach to levels above the method detection
limits for those contaminants using Drinking Water Analytical
methods as described in Tables ISA and 15B. EPA has incorporated
ground water monitoring into Operable Unit One.
• State Comment: The draft ROD states that certain areas of
the site will be capped based on their hazard indices and risk
levels. These areas should be identified and shown on a map in
the ROD. The cap must be effective in preventing infiltration
and lateral ground water flow beneath the capped areas. It
should be demonstrated that the capped areas are extensive enough
to minimize lateral flow infiltration to those areas where
contaminant levels exceed the cleanup requirements.
EPA Response: The areas to be capped include the process area
and selected areas of the spray field. The exact location and
extent of the areas to be capped will be determined by field
confirmation sampling in the remedial design stage.
• State Comment: The discussion of principle threats
identifies "Organic Hot Spots" of TCE and TCB as the principle
threats at the site. While the areas of VOC contamination will
be treated, the areas of TCB contamination will only be
contained. Also, on page 14 of the draft ROD, chromium is
identified as the contaminant associated with the highest hazard
quotients. If TCB is considered a principle threat and chromium
has the highest hazard quotients, why are TCB and chromium
contaminated areas merely being contained (by the cap and slurry
wall) and not treated to reduce toxicity and hazard?
EPA Response: Although chromium may be associated with the
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highest hazard quotient (refer to page 13 of ROD for definition
of hazard quotient), the contaminant does not represent a
"principle threat" (refer to page 16 of ROD for definition of
principle threat. Likewise the TCB does not represent a
"principle threat". Engineering controls are an appropriate
response for addressing contaminants that do not represent a
principle threat.
• State Comment: The draft ROD states on Page 20 that vapor
extraction systems would be installed in areas of the site where
the concentration of VOCs in the soil exceeds levels that "are
not a threat to groundwater". Is this based upon leaching to
ground water above background levels or above MCLS? The
Department recommends the use of MDLs, not MCLs in determining
cleanup requirements.
EPA Response: EPA has revised the ROD to state that VOC systems
would be installed in the areas of the Site where the
concentration of total VOCs in soil exceeds 22.8 mg/kg. Cleanup
levels in soils are not based on the use of MCLs or MDLs to back
calculate a cleanup level in soil, but rather the VE system shall
operate until nondetect levels or no significant removal levels
of the determined indicator compounds have been demonstrated for
three consecutive months and subsequent spike values reveal
nondetect or no significant removal levels.
• State Comment: The Department suggests that the stream
water and sediments and ground water be considered a separate
operable unit.
EPA Response: The ROD clearly states that ground water and
mercury contamination of the stream corridor will be addressed in
Operable Unit Two.
• State Comment: The remedy does not specify institutional
controls to ensure long-term effectiveness and permanence. The
ROD should include deed restrictions.
EPA Response: Deed restrictions have been added to the remedy.
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