EPA Superfund
Record of Decision:
Fields Brook Site, OU 4
Ashtabula, OH
6/30/1997
PB97-964114
EPA/541/R-97/116
January 1998
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RECORD OF DECISION
OPERABLE UNIT §4
FLOODPLAINS/WSTLANDS AREA
FIELDS BROOK SITE, ASHTABULA OHIO
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OUTLINE
DECLARATION FOR THE RECORD OF DECISION p. i
RECORD OF DECISION SUMMARY p. 1
I. SITE NAME, LOCATION, AND DESCRIPTION p. 1
II. SITE HISTORY AND ENFORCEMENT ACTIVITIES p. 2
III. HIGHLIGHTS OF COMMUNITY PARTICIPATION p. 3
IV. SUMMARY OF SITE CHARACTERISTICS p. 4
A) Overview '.. p. 5
B) FWA Exposure Units p. 6
C) Summary of Sampling Data p. 7
D) Soil Sampling Data Summary. p. 8
E) Summary of Soils Data for FEU 2 . p. 9
F) Summary of Soils Data for FEU 3 p. 10
G) Summary of Soils Data for FEU 4. -.. p. 10
H) Summary of Soils Data for FEU 6-......'.... p. 11
I) Summary of Soils Data for FEU 8 p. 12
V. HUMAN HEALTH RISK ASSESSMENT p. 12
A) Chemicals of Concern p. 12
B) Exposure Assessment p. 13
C) Human Health Risk Assessment p. 14
VI. ECOLOGICAL RISK ASSESSMENT p. 17
VII. SCOPE OF THE SELECTED REMEDY P. 17
VIII. DESCRIPTION OF ALTERNATIVES: p. 17
A) Overview and Discussion p. 17
B) Alternative Listing p. 20
IX. SUMMARY OF COMPARATIVE EVALUATION OF
ALTERNATIVES p. 23
A) THRESHOLD CRITERIA p. 24
B) PRIMARY BALANCING CRITERIA p. 27
C) MODIFYING CRITERIA p. 29
X. THE SELECTED REMEDY p. 31
A) Detailed Requirements of the
Selected Remedy p. 31
l) Remedial Action Objectives and
Cleanup Goals p. 31
2) Excavation, Cover, and Disposal
Requirements p.. 34
3) Landfill Requirements p. 34
4) Post-Cleanup Sampling Requirements., p. 35
5) Remedial Activity Locations p. 36
6) Other Requirements p. 37
B) ARARs to be Met p. 38
XI. EXPLANATION OF SIGNIFICANT CHANGES P. 41
XII. STATUTORY DETERMINATIONS. p. 41
ATTACHMENT 1: RESPONSIVENESS SUMMARY. p. 42
I. Comments to 11/96 FWA Proposed Plan..... p. 42
A) Written Comments p. 42
B) Verbal Comments p. 58
II. Comments to U.S. EPA's 10/96
Ecological Risk Assessment p. 63
III. Comments to EPA's FWA Human Health
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Risk Assessment p. 69
IV. Comments to the "Development of the
Cleanup Goals (CUGs)" Section of EPA's
FWA Human Health Risk Assessment p. 76
V. Comments to the FWA Remedial
Investigation Report p. 77
FIGURES:
Figure 1:
Figure 2:
Figure 3:
Figure 4:
Figure 5:
Figure 6:
Figure 7:
Figure 8:
Figure 9:
TABLES:
Table 1-1:
Table 1-2;
Table 1-3;
Table 1-4:
Table 1-5;
Table 2-1:
Table 2-2:
Table 2-3:
Table 2-4:
Table 3:
Table 4-1;
Table 4-2
Table 4-5
Table 5:
Fields Brook Superfund site
Reaches and Exposure Units of Fields Brook
FEU 2-A Response Areas
FEU 2-B Response Areas
FEU 3 Response Areas
FEU 4 Response Areas
FEU 6 Response Areas
FEU 8 Response Areas
On-Site Landfill Cross-Section
Summary of Soils Data for FEU 2
Summary of Soils Data for FEU 3
Summary of Soils Data for FEU 4
Summary of Soils Data for FEU 6
Summary of Soils Data for FEU 8
FWA CUGs: Residential Carcinogen
FWA CUGs: Residential Non-Carcinogen
FWA CUGs: Industrial Carcinogen
FWA CUGs: Industrial Nbn-Carcinogen
FWA Human Health and Ecological COCs
Location-specific ARARs
Action-specific ARARs
Discharge Limitations to Surface Water and the
City of Ashtabula POTW
Alternative Evaluation
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DECLARATION FOR THE RECORD OP DECISION
SITB NAMg AND LOCATIpy
Fields Brook Site, Operable Unit IV, Floodplains /Wet lands Area,
Ashtabula, Ohio
T BASIS AD PURPOSE
This decision document represents the selected Final Remedial
Action for the Fields Brook Site, Operable Unit IV
(Floodplains /Wet lands Area), in Ashtabula, Ohio. This 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 (SARA) , and to the extent practicable, with the National Oil
and Hazardous Substances Contingency Plan (NCP) . The decisions
contained herein are based on information contained in the
administrative record for this site.
The State of Ohio does not concur with the selected remedy. The
non- concurrence letter is attached to this Declaration.
r>p>
Actual or threatened releases of hazardous substances from the
site, if not addressed by implementing the response action
selected in this Record of Decision (ROD) , may present an
imminent and substantial endangerment to public health, welfare,
or the environment.
This remedy is intended to be the final action for Operable Unit
IV {Floodplains/Wetlands Area, 'FWA') .of this site. This final
action includes excavation and on-site containment of
contaminated soils and sediments; backfilling and revegetation in
the FWA; installing a cover in certain areas of the FWA; removal
of trees; operation and maintenance and post closure care of the
cover and containment facility; imposition of institutional
controls; and future monitoring. This final action addresses the
migration pathways of incidental .ingestion of FWA soil and
sediments and dermal absorption of contaminants in FWA soil and
sediments.
The major components of the selected remedy include:
- Excavation or cover of contaminated soils and sediments in
the FWA that exceed cleanup action levels; backfill of all
excavation and cover.areas with hydric-compatible soils;
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Removal of all trees in excavation areas, and removal
of all trees below 12" diameter at basal height (dbh)
in cover areas, with vegetation in response areas
considered contaminated, and with live vegetation above
ground surface considered clean if it can be
decontaminated;
Revegetation of all backfill and cover areas, and
revegetation of all areas disturbed during
construction, using erosion mats and native vegetation;
Construction of a temporary access road to allow access to
and along the FWA from the roadways during construction,
made of crushed stone and 1/4-inch thick geonet liner, and
to be removed after construction and disposed of either in
the on-site landfill or if clean in other on-site or off-
site areas;
Consolidation of excavated soils and sediments,
construction debris, and roadways constructed to
implement the remedy if determined to be contaminated,
within an on-site fenced-in containment cell (landfill)
to be built on one of the industrial properties located
within the Fields Brook watershed;
Construction of a minimum of three downgradient wells
and one upgradient well to monitor the long-term
effectiveness of the landfill;
Long term operation and maintenance and post closure care of
the remedial action to help ensure its effectiveness;
Long term monitoring including sampling of FWA surface soils
and sediments, and backfill and cover areas, and monitoring
of wetland conditions at specific locations and for
parameters defined in the Record of Decision Summary* to
verify the effectiveness of the remedial action;*
Placement of institutional controls on deeds and title for
properties where: contamination will remain in the FWA; the
landfill will be constructed; or hazardous substances,
pollutants or contaminants will remain above levels that
allow for unlimited use and unrestricted exposure. For the
landfill, the deed restrictions must prevent residential,
industrial or other development on the landfill. For all
other properties, the deed restrictions must provide notice
to any subsequent purchaser or prospective developer of the
presence of hazardous substances and of the requirement to
conduct all development activities in such a manner as to
not release contamination towards Fields Brook; and
-11-
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Implementation of access restrictions, including enclosing
the entire landfill area with a fence and posted warning
signs.
STATUTORY DRTBRMIKATIONS
This final Remedial Action is protective of human health and the
environment, complies with Federal and State applicable or
relevant and appropriate requirements and is cost-effective. The
selected remedial action utilizes permanent solutions and v
considered use of alternative treatment technologies to the
maximum extent practicable. However, due to the significant
volume and heterogeneous distribution of waste at the Site,
treatment as a principle element is not considered practicable at
the Site. Thus, this remedy does not address the statutory
preference for treatment that reduces toxicity,.mobility, or
volume as a principal element. However, treatment is a secondary
element in that landfill leachate liquids will be collected and
treated resulting in destruction of hazardous substances.
A review of the remedy will be conducted five years after
commencement of the remedial action to ensure that the remedy
continues to provide adequate protection of human health and the
environment.
Date David A. Ullrich
Acting Regional Administrator
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State of Ofcta Buvbamunfea fntoeiioa Agucy
im*t«'r in MKI «*•.«»)««« SMO po. 809(1049
COWT0UI.UM4321S-10M Cotamfeu*. OH 43»l6-'G4a
RE: Field* Biuuk Supoflind Site
June 10, 1997 FloodpUin/Wetlind Area
Ohio EPA ID# 204-0300
Afhtabula County
Valdas V. Adamkus
Regional Director
USEP A Region V
77 West Jaduoa Blvd.
Chicago, tt. 60604
DMT Mr. Adarakua:
This lew U in response to the Record of Decision (ROD) for the floodpuuo/wetland area
operable unit (FWA) of the Fields Brook Superfuod Site ia Aabtabuta County, Ohio.
Tb» St«t» of Ohio hat expoMed couwsna about the aotoeMd remedy fbrtheFWAinoommeni
letten and to tedmictl meetings with USEPA. Our oooccnn are included as part n/1 Attachment
110 the KOD (Rasponiiveneti Summary for the FWA) ThUkctercootaiMoomiBentiftDmtfae
natural mmrcc truflMtt (Ohio FPA, U.S. Dapt of *• Interior and NOAA) cal and phynoal pcoecaKa. We
oontinue to disagree with the exposure frequencies USEPA used to calculate the deanue goals
(CUGs). USEPA assumed that, in the reMdential area, exposure frequency to FWA soils would
be 61 daytfyr for children, 110 dayt*yrfor adoieeoents and 37 dayi/yr for adults over* 10 y«r
period. We do n« fed thai these exposure (reo^jendw are sufflciendy protect
FWA rfutt are dtrectiy behind reKtifenc^s and feel fkat 270 daya/yr for all agea It a rcwunably
conservative exposure frequency that takes into account inclement weadier conditions
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Valdas V Adankus
Page - 2 -
In on effort to reduce dupUctikw of agency efforts on Superfiind Sites, Ohio EPA, in 1996.
relinquished its role as in active participant in the technical review and comment process for the
Fields Brook Site and thus left it toUSEPA to negotiate an acceptable remedy with the Fields
Brook Action Group (FRAG). Our role after that wasaa a trustee of natural rcMiurooi. As such
we have provided oonunenti along with the other trustees. The trustee group attempted to
ocftjotuttc change* tuthe remedy with FBAG during the past year but were unable to persuade
FB AC to main any changes to me remedy, Instead we reached aa agreement in principle tor *
financial settlement with FBAG to compensate the trustees tV past and future injuries to the
natural mourees. The FBAG agreed to fond the aquuhion and enhancement of wetlands and
some future biological monitoring to assess contouring damages and, we hope, to measure some
uupixivcuumt over tune,
Our final effort to affect changes to the remedy came in die form of comments toe trustees
provided to USEPA during m« public comment period fa UM Proposed Plan (Attachment I).
USEP A offers responses to each of our comments but does not propose to make any changes to
me remedy. In view of this and tor all of the reasons stated in this letter and inthetmstee
comments, Ohio EPA does not concur with the ROD fhr the Fidd$ Brook FWA operable unH.
Ploace foci fra* to contact Ohio ETA should you h»ve any questions or concerns regarding this
letter
Ohio Environmental
DRS/RSWwmk
cc: Jenny Tiell, Deputy Director, CO
Jan Carlson, DERR, CO
Mik« Cxeczele, DERR, CO
Ray Betumier. DERR, CO
BiU Skowrooski, Distria Chief, NEDO
Bob WyMBftki, AMUtuit District Chief, NEDO
Rod Beala, DERR. NEDO
Steve Love, DERR, NEDO
Sig Williams, DERR, NEDO
Heidi Sorin, DERR, CO
JefTHnnfley. Legkl. CO
Peter Whrtehouse. DERR, CO
VancMW Suagcrwald, DERR, CO
Tim Kern. Ohio AGO
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RECORD OF DECISION SUMMARY
FLOODPLAINS/WETLANDS AREA
FIELDS BROOK SITE, ASBTABULA OHIO
I. SITE MAKE, LOCATION, AND DESCRIPTION
The Fields Brook site is located in northeast Ohio, in Ashtabula
County, approximately 55 miles east of Cleveland, Ohio. The
brook drains a six square-mile watershed including an industrial
area where manufacturing activities ranging from metal-
fabrication to chemical production have occurred over the past
50 years. Sediments of the brook, and the Ashtabula River are
contaminated with polychlorinated biphenyls (PCBs), chlorinated
benzene compounds, chlorinated solvents, hexachlorobutadiene,
polyaromatic hydrocarbons (PAHs), arsenic, and other hazardous
substances.
The Fields Brook Site (Site) was placed on the National
Priorities List (NPL) for hazardous waste sites on September 8,
1983. The site consists of Fields Brook, its tributaries, and
any surrounding areas which contribute, potentially may
contribute, or have contributed to the contamination of the brook
and its tributaries. The site is a multi-source site and
involves multiple media, including soil, sediment, groundwater
and surface water.
The U.S. EPA divided-the site into four areas of concern, three
of which have been designated as "operable units" (OUs)
associated with the Fields Brook Superfund site (See Figure 1).
The Sediment OU (OU#1) involves the cleanup of contaminated
sediment in Fields Brook and its tributaries. The Source Control
OU (OU#2) involves the location and clear p of sources of
contamination to Fields Brook to prevent Decontamination of the
brook and Floodplains/Wetlands Area (FWA). The Ashtabula River
Area of Concern involves determining'the type and amount of
contamination in the Ashtabula River, the effect the Fields Brook
and other contamination sources have had on the river sediments,
and any risks to human health and the environment. The FWA OU
(OU#4) involves the cleanup of contaminated soils and sediments
in the FWA which are located within the 100-year floodplain area
surrounding Fields Brook and outside of the channel and sideslope
areas of Fields Brook. The FWA is the subject of this Record of
Decision document.
The FWA has been divided geographically into distinct but
continuous portions. In order to facilitate locating features
and sampling points along Fields Brook and its tributaries, the
stream and system has been divided into segments identified by a
unique numbering system involving stream reaches, which are
depicted on Figure 2. The eastern portion of the Fields Brook
watershed drains Ashtabula Township and the western portion
drains the eastern portion of the city of Ashtabula. The main
channel.is 3.9 miles in length and begins at Cook Road, just
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south of the Penn Central Railroad tracks. From this point,
Fields Brook flows northwest to Middle Road, then west to its
confluence with the Ashtabula River. From Cook Road downstream
to State Route 11, Fields Brook flows through an industrialized
area. Downstream of State Route 11 to near its confluence with
the Ashtabula River, Fields Brook flows through undeveloped and
residential areas in the City of Ashtabula. Fields Brook
discharges to the Ashtabula River approximately 8,000 feet
upstream from Lake Erie. The City of Ashtabula has a population
of about 23,000.
XI. SITS BISTORT AMD ENFORCSKSNT ACTIVITIES
The industrial zone of Ashtabula is concentrated around Fields
Brook and is comprised of several chemical industries and waste
disposal sites. Manufacturing has occurred since the early
1940's in this area. Activities ranging from metal-fabrication
to production of complex chemical products occurred on
approximately 18 separate industrial properties, and the decades
of industrial activity along Fields Brook and its tributaries
resulted in the release of chemical contamination to the Fields
Brook watershed, particularly the sediments of Fields Brook, the
FWA soils and sediments, and the soils surrounding the
industries. These media are contaminated with PCBs, chlorinated
benzene compounds, chlorinated ethenes (solvents),
hexachlorobutadiene, chromium, arsenic, and other organic and
inorganic contaminants.
Between April 1983 and July 1986, a Remedial Investigation/
Feasibility Study (RI/FS) was conducted on the Fields Brook
Sediment OU by the U.S. EPA. The 1986 RI/FS included a baseline
human health risk assessment which demonstrated human health
risks not only for exposure to the brook sediment, but also
exposure in the FWA. The U.S. EPA issued a Record of Decision
(ROD) in September 1986 detailing a cleanup remedy that U.S. EPA,
with the concurrence of Ohio Environmental Protection Agency
(OEPA), determined to be necessary for the Fields Brook
sediments. The 1986 ROD consists of the following components:
excavation, treatment and disposal of sediment from Fields Brook,
an RI/FS to identify current sources of contamination to the
brook and to develop ways to stop further contamination, and an
investigation to address the nature and extent of contamination
in the Ashtabula River and Harbor.
In late 1986, the U.S. EPA began negotiating with a number of
Potentially Responsible Parties (PRPs) to conduct the source
control- OU#2 RI/FS activities and sediment operable unit design
activities. The PRPs are comprised of the companies who are
considered the owners and operators of the chemical industries
and waste disposal sites surrounding Fields Brook. The PRPs also
include the companies who, by contract, agreement, or other
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means, either accepted, or arranged for transport, disposal or
treatment of, hazardous substances within the Fields Brook site.
The PRPs initiated a voluntary assessment of the nature and
extent of contamination in the FWA of the Fields Brook riparian
corridor. Field activities were initiated in Spring of 1993.
Following an extended comment period on the original ecological
risk assessment work plan, the U.S. EPA prepared a separate
ecological risk assessment work plan for the Fields Brook FWA in
March, 1994. Significant portions of this work plan were
incorporated into the PRPs work plan. Three rounds of FWA soil
sampling, additional flora and biota sampling and field
investigations, and a wetland survey which identified the size
and location of wetlands that could be affected by the Fields
Brook cleanup, were completed by the spring of 1995.
The PRPs prepared and submitted to U.S. EPA an initial draft
baseline ecological risk assessment report in June of 1994.
Following U.S. EPA review and comment, the PRPs submitted a
second draft of the ecological risk assessment -in June of 1995,
and upon revision, submitted a third draft in October, 1995. To
produce a more acceptable assessment of potential risk to
ecological receptors at the site, U.S. EPA prepared a separate
ecological risk assessment report in February of 1995. Results
of these efforts are discussed within U.S. EPA's October 1996
Ecological Risk Assessment.
U.S. EPA prepared separate baseline Ecological and Human Health
Risk Assessments for the FWA in 1996. The PRPs voluntarily
conducted an RI/FS for the Fields Brook 'FWA, and have prepared a
FWA Feasibility Study under U.S. EPA oversight. These studies
assess human and ecological risks and cleanup alternatives and
form the basis for cleanup decisions in the wetland areas. These
reports have been placed in the information repositories for this
site. These reports are the primary documents in the FV\ OU#4
administrative record which were used to develop and issue the
Proposed Plan for the FWA in November 1996.
III. HIGHLIGHTS OF COMMUNITY PARTICIPATION
Various public meetings and availability sessions have been held
by U.S. EPA in Ashtabula between 1984 and the present to discuss
the general progress of the ongoing Fields Brook site
investigations.
U.S. EPA has provided regular updates of Fields Brook site
activities to the Ashtabula River Remedial Action Plan (RAP)
Advisory Council at the monthly RAP meetings in Ashtabula.
On May 26-27, 1993, U.S. EPA conducted several availability
sessions and a public meeting in Ashtabula to update the public
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regarding activities for all four areas of concern, including the
FWA, of the Fields Brook Site. After the meeting, U.S. EPA
provided the RAP Council and interested citizens with a written
response to comments and questions raised at the various
meetings. *
On September 26, 1996, U.S. EPA conducted another public
availability session in Ashtabula, and provided the public with a
detailed update regarding the various FWA studies, risk issues
and cleanup alternatives being considered to.be conducted. In
November 1996, U.S. EPA provided the public with a written
'question and answer' response to comments and questions raised
at the September meeting.
U.S. EPA issued a Proposed Plan for the FWA in November 1996.
U.S. EPA provided a public comment period on the FWA Proposed
Plan from November 13, 1996 through January 17, 1997, and
conducted an evening public meeting on the FWA Proposed Plan on
November 21, 1996 in Ashtabula. Also, U.S. EPA met with
officials from the City, Township, and County of Ashtabula on
November 21, 1996 prior to the evening public meeting and
provided these officials with a status update regarding the
Fields Brook site and the FWA. U.S. EPA's response to the public
comments received are summarized in the attached Responsiveness
Summary, which is Attachment 1 of this Record of Decision. This
ROD will become part of the Administrative Record pursuant to the
NCP Section 300.825 (a)(2). The Administrative Record can be
found at the Site repositories located at:
l) Ashtabula County District Library
335 West 44th Street
Ashtabula, OH
2) U.S. Environmental Protection Agency
Waste Management Division Records Center, 7th Floor
77 West Jackson Blvd.
Chicago, IL
IV. SUMMARY OF SITE CHARACTERISTICS
A) Overview:
The FWA consists of the 100-year floodplain of Fields Brook. As
reported in The Soil Survey of Ashtabula County, Ohio, published
by the U.S. Department of Agriculture Soil Conservation Service,
much of the FWA has a natural subsurface composed of glacial
deposits overlying bedrock. Bedrock surfaces in various
locations in the lower reaches of Fields Brook (generally from
Route 11 down to the Ashtabula River), and surface glacial and
Fields Brook sediment depositional soils occur frequently across
the entire FWA. In the upper reaches of Fields Brook (upstream
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of State Street), depth of bedrock approaches approximately 30 to
40 feet. The bedrock is primarily shale with an upper sandstone
unit approximately 3 feet thick. The bedrock is generally not
considered a favorable source of groundwater because of its low
permeability, low porosity, and relatively low yields (less than
3 gpm).
The groundwater in the FWA generally flows towards and discharges
into Fields Brook. In general, Fields Brook is a 'receiving
stream1, meaning that it receives groundwater* from the
surrounding areas including the FWA. Because the soils and silts
in the FWA are generally of very slow permeability and poor
natural drainage, the speed of groundwater within the FWA soils
is generally very slow (1 to 3 feet/year). The combination of
low hydraulic conductivity and relatively slow groundwater
migration has generally prevented people and industries from
using the groundwater in the area, and has prevented contaminants
from entering the groundwater and flowing to Fields. Brook via
groundwater.
The FWA soils mostly do not drain well (i.e., not much
infiltration of rainwater occurs), and the soils are essentially
flat at the surface without hills. The FWA soils are comprised
of either geologically lake-deposited or recent brook-deposited
sediment, and exhibit seasonal wetness and low permeability. The
upper 5 to 15 feet of unconsolidated materials generally consist
of lacustrine silty clay to clayey and sandy silt with rounded
gravel and some silty sand, with variable amounts of organic
matter. Glacial till (Ashtabula Till) underlies the lacustrine
deposits; the Ashtabula till is composed of hard clayey to sandy
silts with angular gravel and rock fragments. A common soil type
in the FWA is the Holly silt loam. These FWA soils generally
have a 4"-6" thick leaf litter, and are covered with native
grasses, brush, shrubs and hardwood trees. Fragmites weeds
frequently cover the soils throughout the FWA.
The FWA area in the downstream reaches of Fields Brook (in the
residential home areas, from Route 11 down to the Ashtabula
River) generally is surrounded by a relatively flat floodplain
area, which spreads out in variable distances from the brook to
the 100-year floodplain edge. In these downstream areas, the FWA
is generally significantly lower topographically from the homes
(between 15-30 feet lower than backyard areas near homes) and is
frequently covered with dense brush and bushes.
A wetland survey, which identified the size and location of
wetlands that could be affected by the Fields Brook cleanups, and
an extensive wetland sampling effort, were completed in the fall
1995. Data from these efforts were included in the October 1996
FWA Remedial Investigation report. Baseline Ecological and
Baseline Human Health Risk Assessments of the FWA were also
completed by the U.S. EPA in October 1996, and are provided as
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separate reports. The PRPs voluntarily conducted an RI/FS for
the Fields Brook FWA, and prepared an October 1996 FWA
Feasibility Study under U.S. EPA oversight. The FWA FS is
provided as a separate report. These studies assess human and
ecological risks in these areas and form the basis for cleanup
decisions in the wetland areas.
B) FWA Bxpomir* Unit*
For risk assessment purposes, reaches of the brook were
segregated into FWA exposure units (FEU) . These FEUs are
indicated on Figure 2. The State of Ohio, U.S. EPA and the PRPs
discussed and agreed on the appropriate size of the FWA exposure
units. Each of the FEUs are approximately 2,000 feet in length,
and correspond to areas where potential exposure to FWA soils
would occur by distinct groups of people on each side of the
brook. Various factors were considered in determining the size
of the exposure units, including review of survey data,
discussions with local citizens, inspection of all FWA areas,
investigations of plants and animals along the FWA, and evidence
of use along the FWA. The U.S. EPA has reviewed these lengths
and concluded that after cleanup activities the average of the
Cleanup Goals (CUGs) for each FEU would be protective of human
health and the environment .
Land use designation for the FEUs were based upon several
considerations: 1) general homogeneity with respect to historical
waste management activities, 2) differences in land use, terrain,
accessibility or media type which can affect exposure scenarios,
and 3) U.S. EPA Guidance documents. It is understood that some
FEUs may not have f loodplains or wetlands but are set up only to
retain a consistent numbering system with the sediment FEUs. The
grouping of FEUs and their associated land use designation
follows.
s
FEU1 Reach 1 FEU2 Reach 2-1, 2-2, and part of 9
FEU3 Reach 3
• Industrials
FEU4 Reach 4 FEUS Reach 11-1 and 11-2
FEU6 Reach 5-1 and 5-2 FEU7 Reach 11-3 and 11-4
FEUS Reach 6 and 7-1 FEU9 Reach 7-2 and 8-1
FEU10 Reach 8-2, 8-3, 8A, 13-1, 13-2, and 13A
Only five of the FEUs contain floodplain soils, or contain
chemical concentrations above the CUGs. These are FEU2, FEU3,
FEU4, FEU6 and FEUS. FEUs 2 and 3 are considered residential
based upon the presence of homes on the property. The industrial
FEUs are upstream of the residential FEUs. There are no fences
along the FWA, and fences do not separate the residential from
the industrial exposure units.
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"I
FEU4, FEU6 and FEUS are considered to have industrial usage for
the following reasons: a) the area east of Route 11 currently
does not have residential development; b) the properties that
fall within FEU4 and FEU6 primarily belong to the industry or the
City of Ashtabula, and do not belong to private land owners; and
c) the properties can be permanently restricted from residential
development through deed restrictions and covenants.
The other five FEUs were eliminated from further consideration
for several reasons. FEUs 1, 5 and 7 do not have a floodplain
area (i'.e., Fields Brook, during a 100 year storm, stays within
the brook channel and does not overflow the banks in these
FEU's). In FEUs 9 and 10, sampling results indicated no
exceedences in the FWA above the CUGs.
C) Summary of Sampling Data
Since 1985, sampling has been done to quantify the levels of
contaminants in the FWA. The FWA soil analytical results
presented in various data reports have been sent to the
information repositories, and represent sampling efforts
primarily performed by the PRP's that .have taken place in the FWA
during the past five years. Some of, the soils data were
collected as part of the brook sampling programs. Additional
surface soil samples were collected at selected locations within
the FWA investigation area to fill data gaps. Surface soil
sampling locations were selected by reviewing existing brook
sediment sampling data and by locating the sampling points in
areas of expected deposition. Sampling locations are shown on
Figures 3 through 7 in the 10/96 U.S. EPA FWA RI Report.
Tissue samples were also collected from mice, shrews, earthworms,
voles, insects, and vegetation and analyzed for 130 separate
chemical parameters. Results of these efforts are discussed in
U.S. EPA's October 1996 Ecological Risk Assessment. PCBs were
observed in the FWA biota. A maximum concentration of 11 ppm
total PCBs was detected in a single shrew composite sample.
However, most concentrations were well below this level ranging
from 0.029 to 4.8 ppm. Arsenic, cadmium, chromium, lead, and
hexachlorobenzene were observed in all tissue matrices throughout
the FWA. Barium, vanadium, and hexachlorobutadiene were observed
in several but not all matrices. Various chemicals of concern,
including several trace metals (lead, cadmium, chromium,
vanadium, and barium), were considered in the ecological risk
assessment. PCBs, hexachlorobenzene, and hexachlorobutadiene
were the organics that were fully assessed in the ecological risk
assessment. Others were eliminated because their levels were not
high enough in the FWA to be of concern to organisms. Summaries
of the biota species collected, biota potentially present,
vegetation identified, wildlife observed, and flora and fauna
sampling data are summarized in Tables 2 through 5 of U.S. EPA's
10/96 FWA Ecological Assessment Report.
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8
D) Soil Sampling Data Summary
A total of 211 FWA soil samples were taken. As part of the
Phase I Sediment Quantification Design Investigation (SQDI)
sampling, 14 sampling locations were randomly selected to provide
a general characterization of site conditions adjacent to the
brook. During Phase II SQDI, 55 sampling locations were located
along transects perpendicular to the Fields Brook channel.
Transects were located near Phase I SQDI sediment sampling
locations that reported elevated concentrations of COC's. During
the Phase III FWA assessment, the 137 sampling locations were
located within each FEU to represent a statistically valid number
of samples. In general, a total of 40 samples were collected
within each of the five exposure units with CUG exceedences:
FEU2, FEU3, FEU4, FEU6 and FEUS. The sampling locations were
spread fairly evenly along each length of the FWA with an equal
number of samples (twenty) on the north and south sides of the
main channel. The sampling locations also included collecting
approximately fifteen 'cross-sections' of the FWA during
sampling. This effort located three sampling locations evenly
spaced on each side of the brook perpendicular to the brook from
the brook to the edge of the FWA. Subsurface soil sampling
(samples collected from the one foot depth below the surface to
the two foot depth below the surface) occurred along five of the
FWA cross sections where the brook sediment data indicated the
highest levels of contamination in the sediment.
The Phase I and Phase II FWA soil samples, taken as part of the
SQDI, were analyzed for approximately 130 different chemicals
(i.e., the TCL and TAL parameters). The 137 Phase III FWA soil
samples were analyzed for eleven chemicals of concern (COCs)
which exceeded cleanup goals in the brov.x sediment; these eleven
COCs were: arsenic, benzo(a)pyrene, beryllium, hexachlorobenzene,
hexachlorobutadiene, hexachloroethane, PCBs, 1,1,2,2,-
tetrachloroethane, tetrachloroethene, trichloroet.'ene, and vinyl
chloride. The soil sampling locations were located by a
registered surveyor.
Soil sampling showed 95 hazardous substances which were detected
in some or all portions of the FWA. As would be expected based
on the'Site1s history, volatile and semi-volatile organic
chemicals, pesticides, PCBs, and inorganic chemicals were
detected in the FWA soils. It was found that levels of
contamination in the FWA soil did not exceed the level of
contamination in the brook sediment.
The physical-chemical properties of the contaminants detected in
Fields Brook affect their fate in the environment. Hydrophobic
organic compounds, like PCB's, are especially persistent in the
environment due to their low solubility in water, high octanol-
water partition coefficients, and high molecular weights. These
organic compounds accumulate into the fatty tissue of organisms
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and will be passed on through the higher orders of the food
chain.
The COC concentrations vary from background and nondetect levels
to several hundred parts per million (ppm or mg/kg) . Maximum
concentrations for some of the semivolatile organics were: 610
tng/kg for total PCB (FEU 6), 480 mg/kg for hexachlorobenzene (FEU
8) , 170 mg/kg for hexachlorobutadiene (FEU 4); for some of the
volatile organics: 56 mg/kg for trichloroethene (FEU 6), 89 mg/kg
for tetrachloroethene (FEU 6), and 8.5 mg/kg for vinyl chloride
(FEU 6); and fcr some of the trace metals: 43 mg/kg for arsenic
(FEU 8) and 57.7 mg/kg for mercury (along the Detrex Tributary to
Fields Brook). Average and upper confidence limit concentrations
and their frequency of detection for all of the chemicals of
concern in FWA soils are summarized in the attached Tables 1-1
through 1-5, and are also provided in Appendix A of U.S. EPA's
10/96 FWA RI Report. All detected levels within FWA soils for
all of the chemicals of concern are summarized in Appendix B of
U.S. EPA's 10/96 FWA RI Report.
The concentrations of all COCs except beryllium, vinyl chloride,
trichloroethene and 1,1,2,2-tetrachloroethane were determined to
be generally equivalent on the north and south sides of the
brook. Beryllium concentrations were statistically different on
the north and south sides of the brook. The average
concentration on the north was 1.86 mg/kg, with a maximum
detected concentration of 19.4 mg/kg, whereas the average
concentration on the south was 0.7 mg/kg, with a maximum detected
concentration of 2.3 mg/kg.
Although there appears to be somewhat more beryllium in the FWA
on the north side of FEU6 and 8 than on the south side,
calculated risks for beryllium are quite low and beryllium is not
a determinant for remediation in either FEU. Vinyl chloride is
rarely detected and influences neither rrsks nor remediation.
Similarly, trichloroethene is somewhat more prevalent on the
south side of FEU2, and 1,1,2,2-tetrachloroethane is somewhat
more prevalent on the south side of FEU3, but; calculated risks
for trichloroethene in FEU2 and 1,1,2,2-tetrachloroethane in FEU3
are extremely low, on the order of 10*10. In conclusion, the
statistical tests indicate that for those COCs that influence
risks and remediation needs, there is no substantial difference
in concentration levels on the north and south sides of Fields
Brook.
B) Sunaary of Soils Data for FEU 2
The most frequently observed organic compounds in FEU 2 were
polynuclear aromatic hydrocarbons (PAHs), PCBs (primarily
Aroclor 1248), bis-2-ethylhexylphthalate, dibenzofuran,
hexachlorobenzene, hexachloro-butadiene, di-n-butylphthalate,
acetone, methylene chloride, tetrachloroethene and- toluene. The
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10
highest detected concentration of total PCBs was 360 mg/kg, with
the average concentration at 24.2 mg/kg. The highest and average
detected concentration of hexachlorobenzene were 97 and 14.3
mg/kg, respectively, and the average hexachlorobutadiene
concentration was 0.81 mg/kg. The maximum detected
concentrations of the following inorganic COCs exceeded the
sediment background concentration established for the Sediment
Operable Unit (SOU): arsenic, beryllium, cadmium, chromium,
lead, and mercury.
Vinyl chloride was not detected in any of the 22 samples
collected on the north side of the brook and was detected in l of
the 22 samples collected on the. south side of the brook.
Therefore, vinyl chloride concentrations were statistically
different on the north and south sides. In addition,
trichloroethene concentrations were also found to differ between
the north and south sides; the maximum detected concentrations on
the north and south were 0.15 mg/kg and 6.8 mg/kg, respectively.
The concentrations of all other COCs were determined to be
generally equivalent on the north and south sides of the brook.
F) Summary of Soil* Data for FEU 3
The most frequently observed organic compounds in FEU 3 were
PAHs, PCBs (primarily Aroclor 1248), di-n-butylphthalate, bis-2-
ethylhexylphthalate, methylene chloride, tetrachloroethene, and
hexachloro-benzene. The highest detected concentration of total
PCBs was 530 mg/kg, with the average concentration at 29 mg/kg.
The highest and average detected concentrations of
hexachlorobenzene were 99 and 6.4 mg/kg, respectively, and the
average concentration of hexachlorobutadiene was 2.8 mg/kg. The
maximum detected concentrations of the following inorganic COCs
exceeded -the sediment background concentration established for
the SOU: arsenic, beryllium, cadmium, chromium, and mercury.
1,1,2,2-Tetrachloroethane concentrations were statistically
different on the north and south sides of the brook. The maximum
detected concentrations on the north and south were 0.022 mg/kg
and 0.22 mg/kg, respectively. The concentrations of all other
COCs were determined to be generally equivalent on the north and
south sides of the brook.
6) Summary of Soils Data for FBTT 4
The most frequently observed organic compounds in FEU 4 were
PAHs, PCBs (primarily Aroclor 1248), l,2-dichloroethene, 1,2,4-
trichlorobenzene, 1,1,/2,2-tetrachloroethane, acetone, 2-butanone,
tetrachloroethene, trichloroethene, bis-2(ethylhexyl)phthalate.
di-n-butylphthalate, hexachlorobenzene and hexachlorobutadiene.
The highest detected concentration of total PCBs was 560 mg/kg,
with the average concentration at 63 mg/kg. The highest and
average detected concentrations of hexachlorobenzene were 230 and
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11
29 mg/kg, respectively, and the average concentration of
hexachlorobutadiene was 9.2 mg/kg. The maximum detected
concentrations of the following inorganic COCs exceeded the
sediment background concentration established for the SOU:
arsenic, beryllium, cadmium, chromium, lead, and mercury.
The concentrations of all COCs were determined to be generally
equivalent on the north and south sides of the brook.
H) Summary of Soils Data for FSU €
The most frequently observed organic compounds in FEU 6 were
PAHs, PCBs (primarily Aroclor 1248), 1,1,2,2-tetrachloroethane,
1,2,4-trichlorobenzene, 1,2-dichlorobenzene, 1,2-dichloroethene,
1,2-dichlorobenzene, bis-2-ethylhexylphthalate, methylene
chloride, acetone, tetrachloroethene, trichloroethene, and
xylenes. The highest detected concentration of .total PCBs was
610 mg/kg, with the average concentration at 76 mg/kg. The
highest and average detected concentrations of hexachlorobenzene
were 320 and 33 mg/kg, respectively, and the average
concentration of hexachlorobutadiene was 11 mg/kg. 'The maximum
detected concentrations of the following inorganic COCs exceeded
the sediment background concentration established for the SOU:
arsenic, beryllium, cadmium, chromium, lead, and mercury.
Beryllium concentrations were statistically different on the
north and south sides of the brook. The average concentration on
the north was 1.36 mg/kg, with a maximum detected concentration
of 6 mg/kg, whereas the average concentration on the south was
0.6 mg/kg, with a maximum detected concentration of 2.2 mg/kg.
The concentrations of all other COCs were determined to be
generally equivalent on the north and south sides of the brook.
Radionuclide sampling occurred on the RMI Extrusion property
which lies within FEU6. In 1985, the RMI Titanium Company
Extrusion Plant conducted an extensive baseline characterization
study to determine uranium levels in soil in the vicinity of the
plant. As part of the 1985 sampling campaign, eleven samples
were taken in the Fields Brook floodplain. As a result of the
1985 baseline characterization, several locations, including
three floodplain locations were selected for annual resampling.
Also, additional radionuclide data were collected on the RMI
Extrusion facility as part of RMI's decommissioning efforts. 74
FWA samples were taken within floodplain areas behind RMI-
Extrusion for Uranium isotopes U-234 and U-235, and for
Technetium-99; 132 FWA samples were taken behind RMI-Extrusion
for U-238. The results are summarized in the 12/95 and 9/30/96
RMI reports which have been provided in the Fields Brook Site
Administrative Record. There were several individual sampling
point detections of total uranium radionuclides in FWA areas,
ranging up to 110 picocuries per gram (Pci/g).
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12
I) Summary of Soils Data for PBU 8
The most: frequently observed organic compounds in FEU 8 were
PAHs, PCBs (primarily Aroclor 1248) , dimethyl-phthalate,
diethylphthalate, butylbenzylphthalate, bis-2-
ethylhexylphthalate, carbazole, dibenzofuran, 1,2-dichloroethene,
1,1,2,2-tetrachloroethane, 1,2,4-trichlorobenzene, 1,4-
dichlorobenzene, trichloroethene, tetrachloroethene, 2-butanone,
hexachlorobenzene, hexachloroethane and hexachlorobutadiene. The
highest detected concentration of total PCBs was 270 mg/kg, with
the average concentration at 34 mg/kg. The highest and average
detected concentrations of hexachlorobenzene were 480 and 30
mg/kg, respectively, and the average concentration of
hexachlorobutadiene was 1.2 mg/kg. The maximum detected
concentrations of the following inorganic COCs exceeded the
sediment background concentrations established for the SOU:
arsenic, beryllium, cadmium, chromium, lead, and mercury. The
concentrations of all COCs were determined to be generally
equivalent on the north and south sides of the brook.
V. HUMAN HEALTH RISK ASSESSMENT
Based on analytical data collected during the FWA remedial
investigation, a risk assessment was performed to determine the
potential risks to human health posed by the contaminants
detected in the FWA soils and sediments. The risk assessment is
a baseline risk assessment and assumes that no corrective action
will take place in the FWA, and that no site-use restrictions or
institutional controls such as fencing or construction
restrictions will be imposed. The FWA human health risk
assessment determines th', actual or potential carcinogenic risks
and/or toxic effects thae chemicals detected in the FWA pose
under current and future'land use assumptions.
A) ChwBicals of Concern
U.S. EPA's October 1996 Fields Brook FWA Human Health Risk
Assessment focused on 11 chemicals of concern (COC) which were
the 11 COCs which exceeded any of the Fields Brook sediment
operable unit cleanup goals (CUGs) on average for any sediment
exposure unit. The Fields Brook Sediment Operable Unit CUGs are
outlined in U.S. EPA's August 3, 1993 and August 18, 1993 letters
to Mr. Joseph Heimbuch of de maximus, Inc., and the CUG
exceedences are described in the February 1995 30% design
document (these letters and the 30% design document are in the
Fields Brook Site Administrative Record). These COC are
indicated in Table 3 and include arsenic, benzo(a)-pyrene,
beryllium, 1,1,2,2,-tetrachloroethane, tetrachloroethene,
trichloroethene, hexachloroethane, vinyl chloride,
hexachlorobenzene, hexachlorobutadiene, and PCBs.
Hexachloroethane and vinyl chloride were screened out as COCs in
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13
the U.S. EPA 1996 FWA human health risk assessment because they
were detected at a frequency of less than 5 percent. The FWA
human health risk assessment focused on the 11 COC which exceeded
the sediment cleanup concentration goals which were determined
during the Fields Brook sediment remedial design. The FWA COC,
their detection frequency and detected concentrations are
presented for each FEU in Tables 1-1 through 1-5.
B) Exposure AcsesoMnt
An exposure assessment was cone"-acted as part of the human health
risk assessment. The potential risks to people exposed to the
FWA include risks from ingestion of soils in the FWA, inhalation
of dusts from the area, dermal exposure to the soils, and
gardening in the FWA. The greatest potential risks to people are
from ingestion of soils in the FWA. U.S. EPA's review of these
risks indicate that if risks from ingestion of soil are
addressed, the other risks to humans and the environment would
also be addressed.
Current and future land use was divided between residential (in
FEUs 2 and 3) and commercial/industrial (in FEUs 4, 6, and 8) as
part of the exposure assessment. U.S. EPA's development of the
CUGs assumed that people would be exposed at certain frequencies
in the residential and industrial areas. In the residential
area, U.S. EPA assumed that someone would ingest between 50 and
200 milligrams of surface soils 61 days per year for children,
110 days/year for adolescents and 37 days per year for adults,
for a total of thirty years. In the industrial area, U.S. EPA
assumed that someone would ingest 50 milligrams of surface soils
60 days per year for a total of twenty five years.
U.S. EPA's review of the information regarding exposure to FWA
soils indicate that frequent exposure to FWA soils is not likely.
There are six months or more of the year which involve cold
weather in Ashtabula, which tends to inhibit outdoor exposure to
soils. The FWA does not have any buildings or structures, in
part because structures are prohibited from being built within
the FWA because of regular flooding. This lack of building
should lessen the likelihood of human exposure in the FWA. Also,
the FWA is generally different than the immediate backyard lawn
areas of the homes along the brook. The FWA is topographically
lower than the grassy backyard areas (i.e., 10-20 feet lower in
height than the lawn areas) and is frequently separated from the
backyard lawn areas by brush, bushes with burrs and other
obstacles making it difficult to reach the FWA directly from the
homes.
U.S. EPA's research indicates that subsurface exposure below .one
foot of soil depth in residential and FWA backyards generally
does not occur unless erosion or excavation was expected in thac
area (which is not expected to occur). Also, of the 23 deep soil
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samples taken between one-to-two feet from the surface in the
FWA, only two samples indicated levels of any contamination above
the CUGs. These two locations are in the FWA soils between
Columbus Avenue and East 16th Street. The levels of
contamination at these locations are only slightly above the
CUGs.
Plants growing in the FWA, including vegetables grown in the FWA,
generally do not pick up organic contamination such as PCBs and
HCBs. According to scientific studies, this is because their
roots generally do not absorb these contaminants. Leafy trees
such as willows and poplars, and leafy vegetables such as
spinach, cabbage or lettuce which might be grown in the FWA, may
pick up heavy metals such as cadmium> chromium and mercury which
exist in the FWA. However, these metals are generally not
prevalent in FWA soils at elevated levels. Thus, plants were not
considered media containing hazardous substances of concern.
However, roots and vegetative materials growing in areas of FWA
soil contamination may be considered contaminated in part because
the contaminated soil particles may be inseparable from the roots
and vegetative materials.
C) Hunan Health Risk Assessment
The total potential carcinogenic and noncarcinogenic hazard
quotients are presented in Table 6 of the U.S. EPA 1996 FWA human
health risk assessment. The calculation spreadsheets, which
provide additional detail to the individual and overall
contaminant risk profiles, are found in Appendix D of the U.S.
EPA 1996 FWA human health risk assessment.
The total potent al carcinogenic risk associated within each FEU
is greater than the 10"' risk which is considered the departure
point for acceptable risk by U.S. EPA. The potential excess
cancer risks ranged from 1.6 x 10"3 (at FEU 3) to 1.2 x 10"4 (at
FEU 8) . Exposure to PCBs and hexachlorobenzene, both Class B2
carcinogens, contributed the majority of the excess cancer risk.
There is not likely to be a short term risk to anyone walking
along the brook in the FWA. However, there is a calculable
cancer risk to residents, workers, and trespassers due primarily
to.long-term exposures through ingestion of soils and
contaminants in the FWA soils and brook sediments.
In FEU2, FEU3,' FEU4 and FEU6, the hazard indices (HI) are greater
than one, indicating that adverse health effects may occur from
exposure to the site. The hazard indices range from 25 in FEU 3
(due primarily to potential exposures to PCBs) to 1.6 in FEU 8
(due to potential exposures to the same contaminant).' These
values reflect addition of all the Hi's in a given FEU regardless
of the chemical-specific endpoint. Thus, these numbers are
likely to overestimate the non-carcinogenic negative impacts from
chemicals at the Site.
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15
A cancer survey was conducted by the Ohio Department of Health in
June 1987 to assess whether there was any evidence of increased
incidence of cancer to residents who live or lived along Fields
Brook due to potential exposures to contaminants which have been
released from companies along the brook. This survey was not
able to detect statistically significant increases of cancer to
the population within close proximity to Fields Brook when
compared to the total cancer levels indicated for the State of
Ohio and for the United States. However, within that normal
cancer rate, the incidence of brain and central nervous system
cancer was higher than expected compared to both Ohio and the
United States levels. The study also noted that it was not known
if potential exposures by these individuals to Fields Brook area
contamination played a role in these increased incidences. A
detailed follow-up investigation into these cases was conducted
by the Ohio Department of Health in June 1988 and that report is
also included in the information repository. This follow-up
study noted that the increased incidences had an unknown cause,
possibly due to a misclassification of the primary- disease,
environmental factors, or chance alone.
The two major risk drivers at the Fields Brook site are PCBs and
HCB. Risk from these two contaminants account for all of the
additive risk at the site. Beryllium and tetrachloroethene
contribute a risk in the 10~6 range in FEU's 2 and 3 and FEU6
respectively. Both PCB and HCB have, carcinogenic and non-
carcinogenic effects. In addition, both PCB and HCB have been
shown to affect the developing fetus, indicating that the hazard
indices for these two chemicals can be appropriately added.
PCBs encompass a class of chlorinated compounds which includes up
to 209 variations, or congeners, with different physical and
chemical characteristics. Specific combinations of PCB congeners
are generally unique to each site. -PCB congeners are grouped
intc categories of PCBs which are known as Aroclors. Certain
Arodors are commonly associated with insulation systems, others
used in hydraulic, lubricating and heat transfer fluids, and
still others as dielectric fluids in transformers. These three
types of Aroclors were used within the Fields Brook site. It was
agreed upon by both U.S. EPA and the PRPs during meetings in 1994
and 1995 to consider all of the Aroclor's and congeners together
as total PCBs in the risk assessment. The FWA human health risk
assessment has calculated the PCB risk using the cancer slope
factor of 7.7 (mg/kg-day )~l, which was used throughout previous
risk assessment drafts and discussions between U.S. EPA and the
PRPs. The human health risk assessment also calculated risks
using the recently revised and current cancer slope factor of 2.0
(mg/kg-day) "l which was entered onto the Integrated Risk
Information System (IRIS) October 1, 1996. Both of these
calculations were reported in the human health risk assessment
because the timing for the slope factor revision was unknown when
the risk assessment was drafted in the summer of 1996.
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Regarding radionuclides, U.S. EPA's October 1996 Fields Brook FWA
Human Health Risk Assessments provides the Radionuclide CUGs
(RCUGs) which U.S. EPA established for both the Fields Brook
sediment and the FWA soils and sediments. The RCUG
concentrations were conservatively calculated assuming both alpha
and gamma emissions, and the exposure routes used in the
development of the RCUGs were incidental ingestion and external
exposure to direct gamma. U.S. EPA compared all of the
radionuclide data taken on the RMI Extrusion facility and FWA to
the RCUGs. Of the 74 U-234, U-235. and Technetium-99 FWA
samples, there were no U-234 and Technetium-99 RCUG exceedences,
and there were two U-235 RCUG exceedences (these two U-235 RCUG
exceedences were within the FWA areas behind RMI which have been
fenced-in for a number of years). Of the 132 U-23S FWA samples
behind the RMI-Extrusion facility, there were 10 U-23S RCUG
exceedences, with seven exceedences within FWA areas behind RMI
which have been fenced-in for a number of years, and three RCUG
exceedences within FWA areas behind RMI which have been recently
fenced-in.
U.S. EPA's review of the data indicate that radionuclides, and in
particular Uranium, are not considered a chemical of concern
within the FWA because the levels of U-235 and U-238 indicated in
the FWA area were relatively low. The average levels indicated
on the RMI-Extrusion property, and within each residential and
industrial FEU including FEU6 which includes the RMI Extrusion
facility, were below the RCUGs established for U-235 and U-238 by
the U.S. EPA (i.e., the soil levels within the FWA are below the
IxlO"6 risk levels). The Agency for Toxic Substances and Disease
Registry also indicated in its 4/96 health assessment for the
RMI-Extrusion property (copy provided in the Fields Brook site
Administrative Record) that the radionuclide levels indicated on
the property do not pose a significant risk to human health.
Also, to be protective, RMI-Extrusion has recently fenced-in all
areas of RCUG exceedences on its property, installed silt fences
in the downgradient areas of detected radionuclides to catch
suspended silt which may run off the property during rainstorms,
and is also planning to excavate/remove the contaminated soils in
their backyard, including the RCUG exceedence FWA soil areas, and
ship the soil to an approved storage facility in either Utah or
Nevada. The excavation activities are planned to occur in 1998,
and will be conducted in coordination with the ongoing facility
decontamination and decommissioning actions being conducted under
supervision of the U.S. Department of Energy. The excavation
actions will also include delineation sampling in 1997 prior to
the beginning of excavation to ensure that the extent of the RCUG
exceedence areas have been defined.
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VI. ECOLOGICAL RISK ASSESSMENT
U.S. EPA' prepared an October 1996 Ecological Risk Assessment
Report which evaluated risks associated with doses of
contaminants to ecological receptors by comparing receptors
against reference doses to calculate hazard quotients (HQs).
Various chemicals of concern (COG) were identified, as indicated
in Table 3, and the ecological risk assessment focused on barium,
cadmium, chromium, lead, mercury, vanadium, hexachlorobenzene,
hexachlorobutadiene, and PCBs. The PHA COC, their detection
frequency and detected concentrations are presented for each FEU
in Tables 1-1 through 1-5. The HQs are presented for all species
and zones in Tables 5-1 through 5-3 in the ecological risk
assessment for exposures using: 1) mean media concentrations and
area use factors (AUFs) as presented; 2) 95 percent upper
confidence limit (UCL) concentrations and AUFs as presented; and
3) 95 percent upper confidence limit on the mean (UCLM)
concentrations and AUFs set equal to 1.0, respectively. Using
this information, along with originally determined.toxicity
reference values (TRVs), HQs were calculated for each ecological
receptor, COC, and Zone (including reference or "background"
locations) when sufficient information existed to do so. Results
based on original calculations are presented within the
ecological risk assessment. As indicated on these tables, a
number of different receptors of concern including mink, hawk,
shrew, mouse, heron, robin and rabbit have HQs which exceed 1 for
multiple contaminants of concern.
VII. SCOPE OF THE SELECTED REMEDY
The purpose of this Record of Decision (ROD) is to select the
final remedial action for the Fields Brook Site FWA. This final
remedy contains or removes the contaminated soils and sediments
from the FWA through a combination of excavating with backfilling
and landfilling, or covering the contaminated soils. All
excavated materials will be contained on-site in a lined
landfill, and all cover and excavation areas will include removal
of trees and revegetation with native vegetation. Operation and
maintenance, post closure care and future monitoring will occur,
and institutional controls and access restrictions will be
placed.
The remedy addresses all exposures to media and releases to
migration pathways that are considered to present an unacceptable
risk, including incidental ingestion of soil and dermal
absorption of contaminants in soil, and releases to surface
water,, ground water, surface sediments, and wetlands.
This remedy does not include treatment of principle threat wastes
in order to reduce toxicity, mobility, or volume of the
contamination. As discussed in greater detail later in this ROD,
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18
treatment is not practicable in part because of the significant
volume of the waste, the contaminated FWA soils will be non-
mobile, the low average concentration of the materials in place
and to be excavated, and.there are no residential or industrial
FWA exposure units which have principle threat concentrations of
contaminants on average greater than a 10'* cancer risk for the
FWA. However, treatment is a secondary element in that landfill
leachate liquids if they are generated will be collected and
treated resulting in destruction of hazardous substances.
VZZZ. DESCRIPTION OF ALTERNATIVESi
A) Overview and Discussion:
The FS identified and evaluated alternatives that addressed
threats and potential threats to human health and the environment
posed by the COCs in the FWA. These remedial alternatives have
several common components including site preparation, placement
of institutional controls, and surface controls- (such as soil
erosion control and revegetation of excavation and cover areas
and areas of disturbance) .
The cleanup objectives for contaminants in the FWA are to conduct
a cleanup which would be protective of human health and the
environment. Each alternative evaluated in the FS and listed and
discussed in this ROD other than the no action alternative
involves excavation and/or containment of FWA contamination. The
extent of excavation and/or cover activities varies between the
different alternatives. Each alternative attempts to meet the
cleanup objectives by conducting a cleanup which would result in
residual FWA contamination levels which are at or below the
cleanup goals (CUGs) on average in each FEU on each side of the
brook. The CUGs for each of the FWA contaminants are listed in
Tables 2-1 through 2-4 of this ROD, and are based in part on a
human health risk associated with 1x10"' range for carcinogens
and a less than one hazard index. This FWA CUG list is taken
from EPA1s 10/20/94 CUG letter to the PRPs, and is also attached
to U.S. EPA's 1996 FWA Human Health Risk Assessment. The only
exception to this CUG list are the CUGs for total PCBs in the
residential and industrial areas of the FWA', which have been to 1
ppm on average in residential areas and 6 to 8 ppm on average in
industrial areas.
Also, each of the alternatives evaluated in the FS segregated
sections of the FWA into FWA exposure units (FEU). These FEUs
are indicated on Figure 2. The State of Ohio, U.S. EPA and the
PRPs discussed and agreed on the appropriate size of the FWA
exposure units. Each of the FEUs are approximately 2,000 feet in
length, and correspond to areas where potential exposure to FWA
soils would occur by distinct groups of people on each side of
the brook. Various factors were considered in determining the
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19
size of the exposure units, including review of survey data,
discussions with local citizens, inspection of all FWA areas,
investigations of plants and animals along the FWA, and evidence
of use along the FWA. The U.S. EPA has reviewed these lengths
and concluded that after cleanup activities the average of the
CUGs in each FEU on each side of the brook would be protective of
human health and the environment.
A remedial approach which is directed at PCB and HCB would
effectively address the primary risk at the site and would also
remove other COCs in the FWA. This is due to several reasons: a)
the dominant risk in the FWA to both human and ecological
receptors is from PCB and HCB; b) the significant levels of all
other COCs exist where elevated levels of PCBs and HCB exist, as
indicated in part by the 12/11/96 "FWA Delineation Sampling Maps"
deliverable from Woodward Clyde which has been included in the
Administrative Record; and c) based on a review of the data, U.S.
EPA has found that if a remedial cleanup to the HCB and PCB FWA
CUGs on average throughout each exposure unit occurs, the low
levels of all other contamination and other COCs remaining in the
FWA after cleanup is completed would be protective of human
health and the environment for each exposure unit.
To help demonstrate that the response areas are properly defined,
all of the remedial alternatives except no action would have
delineation sampling conducted in each FWA exposure unit prior to
the beginning of construction to ensure that the response areas
are properly defined to meet the remedial action objective for
that remedial alternative. Also, all of the excavation and cover
alternatives include the following activities: a) long term
operation and maintenance and post closure care of the remedial
action to hei.p ensure its effectiveness; b) long term monitoring
including sampling of FWA surface soils and sediments, the
backfill and cover areas, and monitoring of wetland conditions at
specific locations and for various parameters to verify the
effectiveness of the remedial action; and c) compliance
determinations to be made with floodway/floodplain regulations
with compensation for loss or damage to wetlands. All of the
alternatives, including the no-action alternative, include
imposition of deed restrictions and access restrictions over the
Site property.
Regarding the cover alternatives, U.S. EPA investigated several
potential ways that contaminants could reach the surface of a six
inch soil cover. These include movement to the surface by
earthworms, burrowing animals, and by other mechanisms. U.S. EPA
has reviewed these mechanisms and has determined that if the
lower levels of contaminants present in the residential area are
covered, it is not likely that these contaminants would reach the
soil surface at levels of concern to humans.
Whenever excavation or cover of contaminated soils and sediments
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in the FWA is considered, backfill of all excavation or cover
areas would occur using hydric-compatible soils. These are soils
that contain seeds, organics and other properties necessary for
vegetative regrowth in the wet environment. Also, removal of all
trees in excavation areas, and removal of all trees below 12"
diameter at basal height (dbh) in cover areas, would occur, with
roots in response areas considered contaminated, and with
vegetation above ground surface considered clean if it can be
decontaminated. Revegetation of all backfill and cover areas,
and revegetation of all areas disturbed during construction,
would occur using erosion mats and native vegetation.
Based on sampling data .available, the alternatives other than no
action consider excavation and/or covering of volumes between
8,000 and 27,000 cubic yards of FWA soils. Additional
investigation to define the extent of PCB contamination in every
2,500 square feet of the FWA downgradient or downstream from the
furthest upstream FWA area requiring remediation in FEUS will be
conducted for each of the alternatives other than no-action, and
additional investigation to define the extent of HCB
contamination in FEU's 4 and 8 will be needed due to elevated HCB
sampling results in these areas, prior to the beginning of
construction to help define the extent of soil excavation and
cover areas.
In addition. Alternative 7 includes additional design delineation
investigation activities and enhanced long term monitoring.
The alternatives other than no action will also involve
construction of a temporary access road to allow access to and
along the FWA areas from the roadways during construction. The
roads will be made of crushed stone and 1/4-inch thick geonet
liner. The temporary road will be removed after construction and
disposed of* either in the landfill or if clean as uncontaminated
solid waste. If the road is considered clean, the crushed stone
may be used if appropriate to assist in the construction of FWA
remedy components, including construction of the landfill.
B) Alternative Listing
The alternatives evaluated in the FS are presented below:
Alternative 1 - No Action
e Estimated Present Worth Cost: $0
• Estimated Construction Time: Immediate
The inclusion of the no action alternative is required by law and
gives U.S. EPA a basis for comparison. This alternative will not
reduce any potential public health or environmental risks
currently associated with the Site. This alternative does not
include any institutional controls over the use of ground water
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or surface water.
Alternative 2 - Containment-Hydric-Coapatible Soil Cover
• Estimated Total Present Worth Cost: $4,600,000
• Estimated Cover Cost, Present Worth: $140,000
• Estimated O&M Cost, 1 year Present Worth: $244,000
• Estimated Construction Time: 12 months
This alternative consists of site preparation, institutional
controls, revegetation, and the placement of a hydric-compatible
soil cover and erosion mat over the Response Areas which exceed
10~6 remedial risk objectives in the residential areas, and 10~5
remedial risk objectives in the industrial areas* The soil cover
thickness would vary from 6 to 12 inches. Physical inspections
and chemical sampling would be part of long-term monitoring.
Wetlands mitigation at off-Site locations is also considered.
Alternative 3A -Hydric-Compatible Soil Cover,. Excavation,
Backfill and Off-Site Disposal
• Estimated Present Worth Cost: ' $8,900,000
• Estimated Construction Time: 12 months
• Estimated Cover Cost, Present Worth: $196,000
• Estimated O&M Cost, 1 year Present Worth: $244,000
This alternative consists of site preparation, institutional
controls, revegetation, and the placement of a hydric-compatible
soil cover and erosion mat over the Response Areas.
Specifically, 'this alternative would excavate, remove and
backfill soils above 30 ppm total PCBs in FEUs 2 and 3, and above
250 ppm total PCBs i FEUs 4, 6 and 8, and place soil cover over
soils above 6 ppm toual PCBs in FEUs 2 and 3, and above 50 ppm
total PCBs in FEUs 4, 6 and 8. Excavation would be limited to 12
inches. Excavated soil would be disposed of at an off-Site
landfill. Physical inspections and chemical sampling would be
part of long-term monitoring. Wetlands mitigation at off-Site
locations is also considered. Approximately 8,000 cubic yards
will be excavated and removed from the FWA under this
alternative, and brought to an off-site disposal facility.
Alternative 3B- Bydric-Compatible Soil Cover, Excavation,
Backfill and Off-Site Disposal
• Estimated Present Worth Cost: $9,500,000
• Estimated Construction Time: 12 months
• Estimated Cover Cost, Present Worth: $285,000
• Estimated O&M Cost, 1 year Present Worth: $244,000
This alternative is similar to Alternative 3A except the Response
Areas were adjusted to require additional excavation near
residential areas. Specifically, this alternative would
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excavate, remove and backfill soils above 30 ppm total PCBs in
FEUs 2 and 3, and above 400 ppm total PCBs in FEUs 4, 6 and 8,
and place soil cover over soils above 8 ppm total PCBs in FEUs 2
and 3, and above 50 ppm total PCBs in FEUs 4, 6 and 8.
Excavation would be limited to 12 inches. Excavated soil would
be disposed of at an off-Site landfill. Physical inspections and
chemical sampling would be part of long-term monitoring.
Wetlands mitigation at off-Site locations is also considered.
Approximately 9,300 cubic yards will be excavated and removed
from the FWA under this alternative, and brought to an off-site
disposal facility.
Alternative 4 - Hydric-Compatible Soil Cover
• Estimated Present Worth Cost: $5,800,000
• Estimated Construction Time: 12 months
• Estimated Cover Cost, Present Worth: $285,000
• Estimated O&M Cost, 1 year Present Worth: $244,000
This alternative is similar to Alternative 2, except the soil
cover and erosion protection mat would be placed over a larger
Response Area than Alternative 2. Specifically, cover would be
placed over the Response Areas which exceed 10~6 remedial risk
objectives in both the residential and industrial FWA areas.
Physical inspections and chemical sampling would be part of long-
term monitoring. Wetlands mitigation at off-Site locations is
also considered.
Alternative 5 • Excavation, Backfill, and Off-Site Disposal
e Estimated Present Worth Cost: $19,000,000
e Estimated Constriction Time: 12 months
e Estimated Cover Cost, Present Worth: $569,000
e Estimated O&M Cost, 1 year Present Worth: $73,000
This alternative consists of site preparation, institutional
controls, revegetation, excavating, and backfilling with hydric-
compatible soils over Response Areas. Excavation would be
limited to 12 inches. Specifically, this alternative would
excavate, remove and backfill soils from FWA Response Areas which
exceed 10"s remedial risk objectives in both the residential and
industrial FWA areas. Physical inspection and chemical sampling
would be part of long-term monitoring. Wetlands mitigation at
off-Site locations is also considered. Approximately 28,500
cubic yards will be excavated and removed from the FWA under this
alternative, and brought to an off-site disposal facility.
Alternative 6 - Excavation, Backfill, Thermal Treatment of
PCB-Containinated Soil, and Off-Site Disposal
e Estimated Present Worth Cost: $21,300,000
• Estimated Construction Time: 12 months
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• Estimated Cover Cost, Present Worth: $569,000
• Estimated O&M Cost, 1 year Present Worth: $73,000
This alternative is similar to Alternative 5, except that, in
lieu of off-Site landfilling, excavated material exceeding 500
n»g/kg PCBs would be transported off-Site for thermal treatment.
Specifically, this alternative would excavate, remove and
backfill soils from FWA Response Areas which exceed 10"6 remedial
risk objectives in both the residential and industrial FWA areas.
Physical inspections and chemical sampling would be part of long-
term monitoring. Wetlands mitigation at off-Site locations is
also considered. Approximately 28,500 cubic yards will be
excavated and removed from the FWA under this alternative, and
brought to an off-site disposal facility.
Alternative 7 • Hydric-Caapatibl* Soil Cover,
Excavation, Backfill, and On-Site Disposal
• Estimated Present Worth Cost: $6,900,000
• Estimated Construction Time: 12 months
• Estimated Cover Cost, Present Worth: $60,000
• Estimated O&M Cost, 1 year Present Worth: $111,000
This alternative consists of site preparation, institutional
controls, revegetation, excavation and backfill, and the
placement of a hydric-compatible soil cover and erosion mat over
Response Areas. Specifically, this alternative would excavate,
remove and backfill soils above 30 ppm total PCBs in PEUs 2 and
3, and above 50 ppm total PCBs in FEUs 4, 6 and 8, and place soil
cover over soils above 6 ppm total PCBs in FEUs 2 and 3.
Excavation would be limited to 12 inches. Excavated soil would
be disposed of at an on-Site ^andfill located at a selected
industrial facility within the Fields Brook Site. Wetlands
mitigation.at off-Site locations is also considered. In addition
to excavation and backfill activities, a 6-inch soil cover would
be placed over all soil areas with ECB contamination of 6 ppm to
30 ppm in FEU2 and FEU3. Physical inspections and chemical
sampling will be conducted as a part of long-term monitoring to
help ensure that the cleanup activities in both of these areas
remain protective of human health and the environment.
Approximately 15,300 cubic yards will be excavated and removed
from the FWA under this alternative, and brought to an on-site
landfill.
II. SUMMARY OF COMPARATIVE EVALUATION OF ALTERNATIVES
The National Contingency Plan (NCP) requires that the
alternatives be evaluated on the basis of the following nine
evaluation criteria: (1) Overall protection of human health and
the environment; (2) Compliance with applicable or relevant and
appropriate requirements (ARARs); (3) Long-term effectiveness and
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permanence; (4) Reduction of toxicity, mobility, or volume
through treatment; (5) Short-term effectiveness; (6)
Implementability; (7) Cost; (8) State acceptance; and (9)
Community acceptance. This section compares the alternatives
with regard to these nine evaluation criteria.
A) THRESHOLD CRITERIA: OVERALL PROTECTION OP HUMAN
HEALTH AND THE ENVIRONMENT AMD COMPLIANCE WITH
APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS
(ARARS) s
Alternative 1, the No Action Alternative, would result in
unacceptable risks under current conditions due to the
detrimental impacts on human and ecological receptors which may
be occurring under current conditions.
Alternatives 2, 3A, 3B, and 4 include either a cpver alternative
solely involving 6 to 12 inches of soil cover, or limited FWA
soils and sediment excavation with cover alternatives involving €
to 12 inches of soil cover, which may cause a detrimental impact
to the wetland ecology and ecological receptors. These
alternatives may not be protective because they may result in
unacceptable risks to humans in the event that the higher
concentration contaminants reach the cover surfaces over time.
These alternatives also would not comply with the TSCA disposal
regulations. Therefore, Alternatives 2, 3A, 3B, and 4 are
eliminated from further consideration.
Of the remaining alternatives, all are protective of human health
and the environment. Alternatives 5, 6 and 7 all provide a
similar level of significant risk reduction and involve a greater
degree of excavation and removal of FWA soils than the other
alternatives. Over the long term, Alternatives 5, 6 and 7 would
be more protective, effective and permanent.
Excavation alternatives, in general, meet che protectiveness
objectives regarding exposure to chemicals in FWA soil and
sediment:. While excavatiom completely removes chemicals from the
soil column, it generally destroys the habitat in place.
Although some wetland communities (those dominated by annual
grasses or herbaceous vegetation) can be effectively restored in
a relatively short time period, others (dominated by woody
species) cannot be restored in a relatively short period. The
ecological value of the latter is generally high, and destruction
of such habitats has negative impacts. Much of the Fields Brook
FWA is wooded. Over much of the area, excavation techniques will
result in destruction of valuable habitat.
Clean cover reduces the potential for chemicals to be exposed to
humans and to the bioaccess-ible and bioavailable pools.
Alternatives providing 6 inches and 12 inches of cover would
offer reduction in ecological exposure. Long-term reduction of
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25
ecological exposure depends in part on the long-term integrity of
the cover.
As discussed previously, plants growing in the FWA, including
vegetables grown in the FWA, generally do not pick up organic
contamination such as PCBs and HCBs, and are not generally
considered media containing hazardous substances of concern.
However, roots and vegetative materials growing in areas of FWA
soil contamination planned for remedial activity may be
considered contaminated in part because the contaminated soil
particles may be closely associated with and inseparable from the
roots and vegetative materials.
Under the 6-inch and 12-inch cover options, while potential for
exposure is reduced, chemicals will remain in the potential
exposure pool. Twelve-inch covers offer greater margin of safety
for long-term protection, but may be likely to stress most trees,
and a number may be killed by reduced oxygen ration. In
addition, the wetland character of the FWA would likely be
degraded, and substantial areas of wetland may be lost as a
result of placing a 12-inch cover. Effects from a 6-inch cover
would be less severe. Transition communities or even communities
expressing primarily upland character are likely to occur more
readily on a 12-inch cover, and thus the habitat may change over
time. A 6-inch cover is unlikely to stress woody vegetation.
Understory, shrub and herb layer communities are likely to re-
establish in largely their present configurations, although some
wetland character may be lost. Such losses may be minimal,
however, because the existing FWA has relatively substantial
elevation differences relative to water table; and wetland
vegetation is pervasive.
•
Cover technologies would be most-suitable for areas with
relatively low levels of contamination, in part because of the
uncertainty associated with the surfacing o.c COCs. With cover in
place, the biologically active surface soil and litter layers
will develop and function. In the ecosystems of the FWA, cover
technologies placed over areas with relatively low levels of
contamination would offer adequate exposure reduction for
ecological receptors with less habitat destruction than
excavation. A well designed, installed, and maintained cover
would provide long-term protection for ecological receptors.
During construction activities there is a possibility that there
could be releases of contaminants to the air above acceptable
limits which assure protection of human health and the
environment. Air monitoring during construction activities in
the FWA and brook sediment areas will be conducted to help assure
that no unacceptable levels of air contaminants are released
during the cleanup. The levels will be compared to short-term
industry standards to ensure protectiveness, as well as to long-
term calculated levels. If any unacceptable releases are found,
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26
cleanup activities would immediately be adjusted to prevent
unacceptable releases of air contaminants.
The potential for recontamination of Fields Brook sediment from
releases of any residual FWA soil contamination after FWA
remediation occurs is expected to be low, particularly for the
excavation alternatives, for several reasons. Because the FWA
CUGs are lower than the brook sediment CUGs, the FWA soils after
remediation will have lower average residual concentrations of
contaminants than the residual average concentrations in brook
sediment, and would thus not be likely to cause recontamination.
Also, the 8/94 sediment scour analysis conducted during the brook
sediment remedial design indicates that floodplain soils would
not be expected to erode from hydraulic scour during a 100-year
rainstorm. Further, the 5/95 "FWA Field Reconnaissance and Photo
Documentation Report" indicates that the FWA is (and would likely
remain) flat and well covered with leaves, shrubs and vegetation
which would help prevent releases of contamination. The scour
and reconnaissance reports are available for review in the
information repositories. Lastly, post-remediation monitoring
and operation and maintenance inspections will help ensure that
the surfacing of elevated levels of FWA contamination would not
occur.
All of the alternatives except no action include a number of
common actions that are necessary to address site risks or to
achieve ARARs, including the following:
1. Site access restrictions;
2. Institutional controls;
3. Additional investigation;
4. Long term monitoring;
5. Remediation of contaminated FWA soils and sediments;
6. Compliance with floodway/floodplain regulations; and
7. Compensation for loss or damage to wetlands.
The ARARs for these remedial actions are indicated in Tables 4-1
and 4-2, and include in part the following:
- surface water quality standards, including the NPDES program
(Clean Water Act.Section 402, 40 CFR 122, 123, 125, 131
Pretreatment Regulations (40 CFR 403), The State of Ohio
NPDES requirements (OAC 3745-33), the State of Ohio Water
Quality Standards (OAC 3745-1); and the State of Ohio
Pretreatment Rules (3745-3);
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actions to minimize the destruction, loss, or degradation of
wetlands in Executive Order 11988 and 40 CFR 6, Appendix A
Section 6(a)(5);
air limits to be met on-site during the cleanup
activities, including limits set by OSHA (29 CFR 1910);
NAAQS (40 CFR 50); various other sections of the Clean
Air Act (and various federal air regulations) between
40 CFR 1 to 99: and various OEPA standards, including
Ambient Air Standards (OAC 3745-17-02A,B,C); Control of
Visible Particulate Emissions (OAC 3734.02(1)); and
other State of Ohio requirements;
regulations and restrictions on construction within
floodways and floodplains, including Permits for Discharges
of Dredged or Fill Materials (33 CFR 320 to 330, Sections
401 and 404 of the CWA) : and Protection of Floodplains (40
. CFR 6, Appendix A):
TSCA disposal regulations at 40 C.F.R. § 761.60 at. aeg.. are
applicable to PCBs in concentrations of 50 ppm or greater
(PCBs) when such PCBs are "taken out of service". Under the
remedial actions being considered, TSCA disposal regulations
could -be triggered by excavation of PCBs which may occur
during the excavation of sediments and soils. Pursuant to
40 C.F.R. S 761.60(a)(4), PCBs must be disposed of: "(i) in
an incinerator which complies with 761.70; or (ii) in a
chemical waste landfill which complies with 761.75." The
TSCA compliant chemical waste landfill disposal method is
generally much less expensive than incineration.
Alternatives 5, 6 and 7 would all be consistent with the ARARs
indicated on Tables 4-1 and 4-2, particularly the OEPA
requirements for disposal of solid waste and TSCA requirements
for disposal of regulated PCB soils and solid waste
B) PRIMARY BALANCING CRITERIA: LONG-TERM EFFECTIVENESS
AND PERMANENCE; REDUCTION OF TOXIC ITT, MOBILITY AND
VOLUME THROUGH TREATMENT; SHORT-TERM EFFECTIVENESS;
ZMPLEMENTABILITY; AND COST.
Alternatives 5, 6 and 7 provide for increased long-term
effectiveness and permanence because they include the removal of
soil from areas of highest contamination concentration in the
FWA, and the covering of these areas of high contamination may
not be permanent nor effective.
None of the alternatives except Alternative 6 include treatment
of principle threat wastes in order to reduce toxicity, mobility,
or volume of the contamination. Principle threats include wastes
which can not be reliably controlled in place such, as liquids,
highly mobile materials, and high concentrations of toxic
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28
compounds. Where treatment technologies are not technically
feasible or available within a reasonable timeframe, the
extraordinary size or complexity of a site makes implementation
of treatment technologies impracticable, or implementation of a
treatment-based remedy would result in a greater risk to human
health or the environment, treatment may not be practicable. Due
in part to the significant volume and heterogeneous distribution
of waste at the Site, treatment as a principle element is not
considered practicable at the Site.
A"1 so, the contaminated FWA soils will be essentially comprised of
non-mobile contamination, because they will be dewatered before
disposal and the contaminants within the soils will be non-liquid
and adsorbed to soil. The FWA soils were contaminated by
deposition of contamination which was flowing in Fields Brook,
and is mostly if not totally comprised of contaminated sediments
deposited from the brook during large storm events. During 1994
design investigations conducted for the Fields Brook sediment
remedy, several leachate samples were taken from untreated
sediment samples taken from four sediment locations with the
highest detected sediment contamination in the brook downgradient
of the major source areas of contamination. The sediment in
these areas had elevated level? of PCBs, volatile organics and
other contaminants. These leachate samples did not contain any
levels which were above hazardous waste levels (i.e., the levels
were below the Toxic Characteristic Leachability Procedure (TCLP)
levels established under U.S. EPA's RCRA program under 40 CFR
261.24) and thus did not exhibit the characteristic of toxicity.
These studies, which are in the information repositories, provide
sufficient information that the FWA soils would not require
treatment through solidification because they would not be
considered hazardous by toxicity characteristic under RCRA, «nd
because the contaminated soils would not be expected to release
toxic liquids once landfilled regardless of the volume of
leachate produced. Also, cnco the excavated FWA soils are
dewatered and placed into the double-lined landfill without
solidification, even if leachate releases did occur, there are a
series of measures which will detect, stop and treat such
releases in the landfill area before any unacceptable risk to
human health of the environmental occurred.
In addition, principle threat wastes generally include wastes
with concentrations greater than a 10'* cancer risk at a site,
and there are no residential or industrial FWA exposure units
which have principle threat concentrations of contaminants on
average greater than a 10"4 cancer risk for the FWA. The cleanup
objectives for contaminants in the FWA include to remove or
appropriately contain contamination to levels which for each
contaminant which are, on average, at or below the cleanup goals
(CUGs). The CUGs for total PCBs in the residential and
industrial areas of the FWA are set at 1 ppm in the residential
area and 6 to 8 ppm in the industrial FWA areas on each side of
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29
the brook in each exposure unit. There are no residential or
industrial FWA exposure units which have existing concentrations
for any contaminant (including total PCBs) which on average would
present greater than a IxlO"4 human health risk. FWA's 2, 3, 4,
6, and 8 have an average total PCB concentration of approximately
50-60 ppm, and the excavated soils will have a low average
concentration of between 100-150 ppm total PCBs. Thus, for these
reasons treatment would not be practicable or required.
However, treatment is a secondary element in that landfill
leachate liquids, if they are generated, will be collected and
treated resulting in destruction of hazardous substances. Thus,
if contaminated liquids leach from the landfilled material, these
liquids will be collected and treated.
No significant short-term risks nor implementability problems are
expected during construction or soon after construction of
Alternatives 5 through 7. There may be difficulty, in restoring
the wetland environment to the preconstruction degree of
vegetation, in part because the removal of large trees from any
excavation areas and smaller trees from cover areas may change
the ecosystem significantly enough that regrowth of the same
species may not occur. Alternatives 5 through 7 would also
provide for short term effectiveness, in part because the
significant areas of contamination within the FWA would be
covered or excavated and removed. This would over the short term
effectively prevent exposure to significant contamination. Air
monitoring will be conducted during construction activities to
help assure that no unacceptable levels of air contaminants are
released during the cleanup.
Alternatives 5 and 6 are more expensive because they require
excavation of all of the contamination present in the FWA above
the cleanup goals and the off-Site disposal and/or treatment of
these excavated materials. Alternative 7 is estimated to cost
between $12 and $14 million less than Alternatives 5 and 6.
C) MODIFYING CRITERIA: STATE AGENCY ACCEPTANCE;
COMMUNITY ACCEPTANCE.
The State of Ohio, through OEPA, has had a number of concerns
regarding the preferred remedial alternative and its
protectiveness of human health and the environment, does not
concur with the U.S. EPA preferred alternative, and has stated
that substantially more contaminated FWA soils should be
excavated from the FWA in order to achieve a more protective
remedy for the environment. Specifically, OEPA wanted U.S. EPA
to select a variation to Alternative 5 which would remove 13,200
additional cubic yards of lower-level contaminated soils over
Alternative 7, at an increased cost of approximately $5.1 million
over the $6.9 million cost of Alternative 7. OEPA also felt that
the exposure frequencies should have been more conservative than
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30
those U.S. EPA used in the FWA human health risk assessment.
OEPA wanted additional days/year for the exposure assumptions
used in developing the cleanup goals (CUGs) for the FWA. U.S.
EPA's development of the CUGs assumed that people would be
exposed at certain frequencies in the residential and industrial
areas. In the residential area, U.S. EPA assumed that someone
would be exposed to FWA surface soils 61 days per year for
children, 110 days/year for adolescents and 37 days per year for
adults, for a total of thirty years. In the industrial area,
U.S. EPA assumed that someone would be exposed to FWA surface
soils 60 days per year for a total of twenty five years. OEPA
finds that 270 days/yr for ages 0-30 would be appropriate, in
part because contamination is located in FWA areas directly
behind residences, and in part because only three months of the
year have an average daily temperature below 32° F for the
Ashtabula area.
U.S. EPA has considered the potential effect of not removing
materials below 30. ppm total PCBs in the residential FWA area,
and below 50 ppm in the industrial FWA area, and finds that the
proposed remedy would be protective of both human health and the
environment. The relatively .low level of potential increased
protectiveness provided by the increased FWA soil excavation
desired by OEPA in the above-noted variation of Alternative 5
does not offset the increased costs required to implement this
alternative over the cost of Alternative 7 (i.e., $5.1 million
increased costs). Alternative 7 offers the best balance between
protectiveness and cost effectiveness of all alternatives,
including the variation of Alternative 5 described above.
As previously stated, U.S. EPA's review of the information
regarding human exposure to FWA soils indicate that frequent
exposure to FWA soils is hot likely. The cleanup in the FWA
soils provided by Alternative 7 will* reduce potential cancer risk
to approximately ore chance in one million after cleanup. These
levels are within the overall remedial action objective target
risk level (10~6) which is being selected for this remedy.
The highest calculated post-remediation Hazard Quotient ("HQ",
which is a term used to assess the potential effects to
ecological receptors of concern) was below 5 for Alternative 7,
and for most receptors of concern was below 1, for each
contaminant within the FWA, as indicated in the 10/96 FWA
Feasibility Study, Attachment 1. These levels are within an
acceptable range and within an order of magnitude of the
acceptable post-remediation objectives U.S. EPA strives to
achieve for all ecological cleanups. U.S. EPA believes that the
response actions to be conducted as proposed for the FWA soils
would protect the various populations of plants and animals which
exist or may exist along the floodplain area for this site.
Alternative 7 will significantly reduce the short- and long-term
risks to ecological populations and reduce these population's
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31
potential uptake of contamination via soil and food to acceptable
levels of exposure. Also, the additional damage to the wetlands
that would occur under the variation to Alternative 5 described
above also weighs against this alternative.
•
U.S. EPA provided a public comment period on the FWA Proposed
Plan from November 13, 1996 through December 17, 1996, and
conducted a public meeting on the FWA Proposed Plan on November
21, 1996 in Ashtabula. Upon a request received from the U.S.
Department of Interior (U.S. DOI) on behalf of the Natural
Resource Trustees (i.e., U.S. DOI, the State of Ohio and the
National Oceanic and Atmospheric Administration) associated with
this site, the public comment period was extended to January 17,
1997. U.S. EPA's response to the public comments received are
summarized in the attached Responsiveness Summary, which is
Attachment 1 of this Record of Decision.
X. THI
The selected remedy is Alternative 7, which involves installation
of a hydric-compatible soil cover, excavation, backfill, and on-
Site disposal of excavated materials. The attached Evaluation
Table (Table 5) indicates that Alternative 7 provides the overall
best tradeoffs with respect to the nine evaluation criteria.
Alternative 7 is the most cost effective alternative which
reduces exposure to contaminants by removing the soil with the
most elevated concentrations of contaminants from the FWA
environment via excavation and on-Site consolidation, and by
covering areas of relatively low level contamination. The
response areas involving areas with FWA contamination at or above
certain PCB and HOB concentrations discussed below are indicated
for Alternative 7 in Figures 3 through 8. The exact dimensions
and locations of the cover and excavation limits will be
developed during the design of U.S. EPA'a selected remedial
alternative.
Specific requirements of this selected remedy are provided below.
A) D«t*il*d R«quir«a*nts of th« S«l«ct«d Rvmadyt
1) RuMdial Action Objectives and Cleanup Goals
The remedial action objectives of the selected remedy are to
reduce the potential for human health cancer risk to one chance
in one million or lower after cleanup, and to reduce the
potential for human health non-cancer risks to levels that are no
longer considered toxic to humans. The remedial action
objectives also are to reduce the potential for ecological risk
to levels that would protect the various populations of plants
and animals which exist or may exist in the FWA. In addition,
the remedial action objectives are to avoid or minimize
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32
destructive impacts to the FWA from construction activities and
the final remedy to the extent practicable in order to protect
the ecological value and existing habitats of the FWA.
The cleanup goals (CUGs) of the selected remedy are the average
concentration per FEU for each contaminant of concern within the
FWA at which the remedial action objectives noted above would be
met and at which exposure by people, plants and animals would be
protective. The CUGs are based on a human health risk associated
with ixlO*6 range for carcinogens and hazard index of less than
one for noh-carcinogens. The CUGs are also within an acceptable
range and within an order of magnitude of the acceptable post-
remediation objectives U.S. EPA strives to achieve for all
ecological cleanups.
The CUGs for each of the FWA.contaminants are listed in Tables 2-
1 through 2-4 of.this ROD. Copies of U.S. EPA's 10/20/94 letter
which includes calculations used to develop these CUGs, and
copies of U.S. EPA's 1/31/94 letter which indicates"Radionuclide
Contamination CUGs, are included in U.S. EPA's October 1996 Human
Health Risk Assessment report. An explanation of the development
of the CUGs is included as an attachment to U.S. EPA's October
1996 Human Health Risk Assessment report.
Regarding ecological risk reduction based on a cleanup to the
CUGs, the highest calculated post-remediation Hazard Quotients
("HQ", which is a term used to assess the potential effects to
ecological receptors of concern) are below 5 for Alternative 7,
and for most receptors of concern are below 1, for each
contaminant within the FWA, as indicated in the 10/96 FWA
Feasibility Study, Attachment l. These levels are within an
acceptable range and within an order of magn ;ude of the
acceptable post-remediation objectives U.S. EPA strives to
achieve for all ecological cleanups. 'The response actions to be
conducted under Alternative 7 would protect the various
populations cf plants and animals which exist or may exist along
the floodplain area for this site and will significantly reduce
the short- and long-term risks to ecological populations and
reducing these population's potential uptake of contamination via
soil and food to acceptable levels of exposure. It should also
be noted that the HQ calculations were developed using
conservative assumptions which would help provide for
protectiveness to ecological receptors.
The only exception to the CUGs listed in Tables 2-1 through 2-4
are the CUGs for total PCBs in the residential and industrial FWA
areas. The total PCB CUGs are set at an average of 1 ppm in the
residential area and an'average of 6 to 8 ppm in the industrial
FWA areas on each side of the brook in each exposure unit.
Regarding the PCB CUGs, U.S. EPA calculated two separate human
health cancer risk CUGs for PCBs in the Human Health Risk
Assessment, one set of CUGs based on the revised CSF and one set
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33
based on the former CSF. The recently revised and current CSF of
2.0 results in PCB cancer risk CUGs of 1.2 ppm on average in
residential areas and 9.6 ppm on average in industrial areas.
The former CSF of 7.7 results in PCB cancer risk CUGs of 0.3 ppm
on average in residential areas and 2.5 ppm on average in
industrial areas. Both of these calculations were reported in
the human health risk assessment because the timing for the slope
factor revision was unknown when the risk assessment was drafted
in the summer of 1996.
Upon consideration of the various issues associated with PCB
risks at the Fields Brook site, U.S. EPA has made a risk
management decision and has set the total PCB CUGs for the
floodplain/wetlands operable unit as follows: 1 ppm on average in
residential areas, 6 to 8 ppm on average in industrial-areas.
These FWA PCB CUGs are slightly lower in concentration than CUGs
based solely on the recently revised CSF, and slightly higher
than CUGs based solely on the former CSF. These FWA PCB CUGs are
based on U.S. EPA's risk management decision to be-protective of
ecological receptors at the site, and to attempt to be protective
and account for the uncertainties regarding the endocrine
disrupter health effects. Also, this decision reflects U.S.
EPA's attempt to account for the potential synergistic effects of
the multiple contaminants in the FWA which may increase health
risks associated with the predominant chemical of concern in the
FWA, which is/are PCBs.
Regarding the need to be protective of ecological receptors at
the site in developing the FWA PCB CUGs, the 1986 FWA Ecological
Risk Assessment indicated the potential for significant risks to
ecological populations associated with exposure to PCBs. It
should be noted that although a FWA remedy which meets the total
PCB CUG of 1 ppm on average in residential areas and 6 to 8 ppm
on average- in industrial areas may still result in chronic hazard
quotients (HQa) which exceed a value of 1 for several species (as
discussed above), and that HQs above 1 may indicate a risk of
adverse effects to species, U.S. EPA believes that a FWA remedy
which meets the above noted PCB CUGS would protect the various
populations of ecological receptors which exist or may exist
within the floodplain area for this site. The response actions
would reduce the short- and long-term risks to ecological
populations and reduce these population's potential uptake of
contamination via soil and food to acceptable levels of exposure.
Regarding the need to attempt to be protective and account for
the uncertainties regarding the endocrine disrupter health
effects in developing the FWA PCB CUGs, it should be noted that
although the PCB cancer risk slope factor changed based on the
final reassessment report of September 1996 from 7.7 to 2, as
noted within the 1996 Human Health Risk Assessment, at this time
there is no agreed-upon quantitative method within U.S. EPA to
incorporate the endocrine disruption data into a toxicity value.
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There is reason to believe that the endocrine, disrupter effect
may be the most sensitive health effect of PCS exposure. Also,
U.S. EPA's general practice is to err on the side of caution
regarding use of uncertain data; the endocrine disruption
uncertainties provide justification for the use of a conservative
PCS cleanup goal calculation. As endocrine disrupters, PCBs have
the potential to negatively impact the developing fetus, increase
vulnerability to certain cancers, and possibly decrease
fertility. While an RFD has not been calculated based on these
endpoints, the current evidence suggests that PCBs have the
potential to disrupt the endocrine system. •
2) Excavation, Cov«r, and Disposal Requirement*s
a) excavate all soil in residential areas with
total PCB contamination above 30 ppm and HCB above 80 ppm, and
excavate all soil in industrial areas above 50 ppm total PCBs and
over 200 ppm HCBs;
b) cover all soil in residential areas with total
PCB contamination between 6-30 ppm PCBs with 6 inches of hydric-
compatible soil, and revegetate using erosion mats and native
vegetation;
c) transport excavated soils, construction debris,
and roadways to a containment cell (landfill) to be built on one
of the industrial properties located within the Fields Brook
watershed;
d) remove all trees .in excavation areas, and all
trees below 12-inch diameter in cover areas; regarding the trees
to be left standing in cover areas, avoid compaction of the roots
and fill to be placed around the tre.es, and use construction
equipment equipped with a retractable boom if feasible so that
the equipment stays outside the dripline of the trees; regarding
roots, any roots, subsurface vegetative materials,, or other
vegetative materials downed before remedial activities commenced,
which are in response areas or require removal to conduct the
remedy will be considered contaminated; any live vegetation above
ground surface not contaminated with soils or sediments and which
can be adequately spray washed if necessary, may be considered
not contaminated, .and generally may be mulched, and used for site
restoration; and
e) backfill all excavation areas with hydric-
compatible soils and revegetate using erosion mats and native
vegetation.
3) Landfill Requirement*
The on-site landfill to be constructed would be located on one of
the industrial properties in the Fields Brook watershed. It
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35
would have a bottom liner and would be covered with a plastic
liner, clean soil and vegetation. It would be surrounded by a
fence with signs posted every 100 feet warning of the presence of
hazardous substances, and would have future monitoring and
sampling to ensure it remains protective. To assure long-term
effectiveness and protectiveness, the landfill would be
constructed to meet the following minimum requirements:
a) Bottom Liner (from bottom to top, as indicated
in Figure 9)»
• choose area wh^re underlying clay is expected to be
continuous, sand lenses not known to exist,, and ground water
not known to be contaminated if possible; grade to level;
• 6-inch thick compacted in-situ clay; the bottom of the clay
shall be at least 5 feet above the historical high ground
water table . .
• 60-mil flexible synthetic membrane liner (FML) which has a
permeability equivalent or less than IxlO*14 cm/sec
• 6-inch thick sand/gravel with leachate detection system
• 60-mil FML liner
• 6-inch thick sand/gravel with leachate collection system
• dewatered contaminated soils/sediment (no rocks/sharp
materials near bottom)
b) Cover (from bottom to top, as indicated in
Figure 9)s
grade
12-inch thick clean soil/gravel (consider need for soil gas
collection or vents)
40-mil FML liner, keyed in
1/4-inch thick geonet liner
24-inch thick topsoil
revegetate
downgradient wells, one upgradient minimum, for monitoring
purposes
4) Post-Cleanup Sampling Requirements
Post-remediation sampling would be initiated in the FWA to
evaluate the remedial action in both the residential and
industrial FEUs. The sampling program would involve the following
components:
a) Residential PBUs- (FKUs 2 and 3)t
• 10 samples across both FEUs are planned to be taken each
year, at locations in the FWA to be determined each year at
U.S. EPA's discretion
• analyze for total PCBs year 1 through 4
• analyze for nine chemicals of concern in year 5 (i.e.,
arsenic, benzo(a)pyrene, beryllium, hexachlorobenzene,
hexachloro-butadiene, PCBs, 1,1,2,2,-tetrachloroethane,
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tetrachloroethene, and trichloroethene)
• review results each year, evaluate data to assess the need
for further sampling and potential changes in sampling
locations, and evaluate the need for remedy repairs, in
accordance with the Superfund Program's National Contingency
Plan regulation (40 CPR Section 300)
• regarding duration of this sampling, post-remediation
monitoring will extend at least for a period of 5 years; at
the end of the 5 year period, a re-evaluation will be made
as to the appropriateness of extending the monitoring time
period (post-remediation monitoring will not necessarily
terminate after 5 years)
b) Industrial FEU* (FEU* 4, 6, and 8)s
• 15 samples across the three FEUs are planned to be taken
each year, at locations in the FWA to be determined each
year at U.S. EPA'a discretion
• ' analyze for PCBs in year 1 through 4
• analyze for nine chemicals of concern in year 5 (i.e.,
arsenic, benzo(a)pyrene, beryllium, hexachlorobenzene,
hexachloro-butadiene, PCBs, 1,1,2,2,-tetrachloroethane,
tetrachloroethene, and trichloroethene)
• review results each year, evaluate data to assess the need
for further sampling and potential changes in sampling
locations, and evaluate the need for remedy repairs, in
accordance with the Superfund Program's National Contingency
Plan regulation
• regarding duration of this sampling, post-remediation
monitoring will extend at least for a period of 5 years; at
the end of the 5 year period, a re-evaluation will be made
as to the appropriates js of extending the monitoring time
period (post-remediation monitoring will not necessarily
terminate after 5 years)
5) Remedial Activity Location*
Figures 3, 4, 5,- 6, 7, and 8 indicate the FWA areas in the
residential areas (FEU2 and FEU3) located between East 16th
Street and Route 11, and in the industrial areas (FEU4, FEU6, and
FEUS) located between Route 11 and about 2,000 feet east of State
Road, where remedial activities would take place under
Alternative 7.
To implement the remedy, additional delineation sampling will be
conducted prior to the beginning of remedial construction
activities to ensure that the response areas are properly
defined. In each FWA.exposure unit prior to the beginning of
construction, one PCB sample will be taken and analyzed in every
2,500 square feet residential FWA area (i.e., one sample every
fifty feet along all north-south and east-west directions), and
in all but twelve 2,500 square feet industrial FWA areas, which
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37
are downgradient or dovmstream of the FEUS CUG exceedence areas.
The twelve industrial FWA areas which are not planned to be
sampled in this delineation effort are located near or along the
outer edge of industrial floodplain areas where CUG exceedences
were not previously indicated. Eight of these locations are in
FEU 6 along the southern edge of the FWA in fenced-in areas of
the RMI-Extrusion property, and four of these locations are in
FEU B on the northeast edge of the FWA. In addition, HCB
delineation samples are required to be taken around proposed
response areas in FEU's 4 and 8 which were developed due to
elevated HCB sampling results. U.S. EPA finds it acceptable to
not do further delineation sampling in existing areas already
slated for response actions.
Excavation and cover of contaminated sediments and surface soils
will occur in those FWA areas designated for excavation, and will
be refined through the delineation sampling. It is anticipated
that based on the data previously collected and to be collected
as described above, the excavation limits can be defined without
additional sampling to be conducted during construction.
6) Other Requirements
A temporary access road would be installed along most of the
floodplain area. This temporary road would be made of crushed
stone and would have periodic access points to existing roadways.
It would be removed after construction and disposed of properly.
The temporary access road would allow access to and along the
floodplain areas from the roadways during construction, be made
of crushed stone and 1/4-inch thick geonet liner, and will be
removed after construction and disposed of either in the on-site
landfill or. if clean in other on-site or off-site areas.
The destruction, loss, degradation or disturbance of any FWA
areas not slated for remedial response activity due to impacts
from construction activities and the final remedy should be
avoided or minimized to the extent practicable, because the
ecological value of the FWA is generally high and destruction or
disturbance of existing FWA habitats would have negative impacts.
Long term operation and maintenance and post closure care of the
remedial action must be conducted to help ensure the remedy's
effectiveness*
Institutional controls must be placed on deeds and title for
properties where: contamination will remain in the FWA; the
landfill will be constructed; or hazardous substances, pollutants
or contaminants will remain above levels that allow for unlimited
use and unrestricted exposure. For the landfill, the deed
restrictions must prevent residential, industrial or other
development on the landfill. For all other properties, the deed
restrictions must provide notice to any subsequent purchaser or
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prospective developer of the presence of hazardous substances and
of the requirement to conduct all development activities in such
a manner as to not release contamination towards Fields Brook.
Reviews of the selected remedy must be conducted every five years
after the remedial action is initiated to assure that human
health and the environment are being protected by the remedial
action. This is required because hazardous substances,
pollutants or contaminants will remain in the FWA and in the
landfill area above levels that allow for unlimited use and
unrestricted exposure.
Access restrictions must be provided to help ensure that the
public is protected from and adequately warned of potential
exposure to the hazardous substances remaining at the site.
These provisions shall minimally include enclosure of the entire
landfill area with a fence with signs posted every 100 feet
warning of the presence of hazardous substances.
B) AXAJta to b« Mats
Section 121(d) of CERCLA requires that Superfund remedial actions
meet ARARs. In addition to ARARs, the ARARs analysis which was
conducted considered guidelines, criteria, and standards useful
in evaluating remedial alternatives. These guidelines, criteria,
and standards are known as TBCs ("to be considered") . In
contrast to ARARs, which are promulgated cleanup standards,
standards of control, and other substantive environmental
protection requirements, criteria or limitations, TBCs are
guidelines and other criteria that have not been promulgated or
are not directly applicable. The selected remedy will comply
with the ARARs and he TBCs listed in Tables 4-1 and 4-2 which
are attached to this ROD.
Location-specific ARARs establish restrictions on the management
of waste or hazardous substances in specific protected locations,
such as wetlands, floodplains, historic places, and sensitive
habitats. Table 4-1 provides a listing of location-specific
ARARs for the selected FWA remedy. Action-specific ARARs are
technology-based or activity-based requirements or limitations on
actions taken with respect to remediation. These requirements
are triggered by particular remedial activities that are selected
to accomplish the remedial objectives. The action-specific ARARs
indicate the way in which the selected alternative must be
implemented as well as specify levels for discharge. Table 4-2
provides a listing of the action-specific ARARs for the selected
FWA remedy. The action-specific ARARs listed in Table 4-2
include the Ambient Water Quality Criteria and the Ohio Water
Quality Standards, which contain specific standards that would be
applicable if remediation water or treatment plant wastewater is
discharged directly to Fields Brook or the Ashtabula River.
Chemical specific ARARs are incorporated into Tables 4-1 and. 4-2.
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• 39
In addition to the water quality criteria, substantive
requirements of National Pollutant Discharge Elimination System
(NPDES), as implemented under Ohio regulations, would also be
applicable to wastewaters planned to be discharged to Fields
Brook which will require treatment. These wastewaters include
liquids generated during construction activities such as
dewatering liquids, excavation area liquids, and liquids
generated during construction of the on-site consolidation area.
Discharges to Publicly Owned Treatment Works (POTWs) may be
pursued as an alternative discharge location. However, such
discharges must also comply with limitations to ensure acceptable
discharge from the POTW after treatment. The specific discharge
levels will be determined during the design stage in coordination
with OEPA.
It .is expected that most of the soils and sediments to be
excavated from the FWA for disposal into the on-site
consolidation area landfill will contain PCBs exceeding 50 ppm.
Excavation of these wastes and soils and consolidation on-site
will be considered disposal of PCBs pursuant to 40 CFR 761.Kb).
In this case, 40 CFR 761.60(a)(2) requires any non-liquid PCBs at
concentrations of 50 ppm or greater in the form of contaminated
soil, rags, or other debris to be disposed of in an incinerator
which complies with 761.70 or in a chemical waste landfill which
complies with 761.75.
The selected remedy provides for disposal of the PCBs in a
landfill that does not meet the following requirements of Section
761.75(b): requirement for a fifty foot distance between bottom
liner and historical high water table (761.75(b)(3). Pursuant to
761.75(c)(4), the Regional Administrator may determine that one
or more of the requirements in 761.75(b) is not necessary to
protect against unreasonable risk of injury to health or the
environment from the PCBs, and may waive such requirements. The
Regional Administrator has waived the requirements in
761.75(b)(3) for a fifty foot distance between bottom liner and
historical high water table for the following reasons:
1. the landfill to be constructed which includes a low
permeability site cover, double lined unit, leachate
collection system, leachate detection system, a bottom clay
liner which shall be at least 5 feet above the historical
high ground water.table, long term monitoring, access
restrictions, and institutional controls will provide
protection to human health and the environment against
unreasonable risks of injury;
2. no significant reduction in the long term risks would be
gained from the off-site disposal of the PCBs contained
within the sediments and soils to be excavated;
3. the costs for off-site disposal of the PCBs is
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40
potentially large; and
4. the consolidation unit to be built will provide for
adequate protection of the underlying groundwater
resource.
Since the remedy provides for containment of the PCB
contamination above 50 ppm, no additional protection to the
public health or the environment would be added by off-site
transport and disposal of the soils in an off-site incinerator
complying with 761.70 or in an off-site chemical waste landfill
complying with 761.75(b), or by requiring the on-site landfill to
comply with all of the requirements of Section 761.75(b).. This
finding and waiver is established by signature to this Record of
Decision, as required in 761.75(c)(4).
The material excavated for permanent disposal into the on-site
consolidation unit will be consolidated and temporarily staged
and stored above the 100 year flood elevation on one of the
industrial properties. The on-site landfill must meet State of
Ohio requirements for construction of a solid waste management
unit including setback requirements.
Regulations related to the dewatering of the soils and sediments
prior to consolidation must be met, including 40 CFR
264.228(a)(2), which requires elimination of free liquids by
removal or solidification. Thus, it is required that dewatering
of the excavated soils and sediments to be landfilled will occur
in part to ensure that no free liquids will remain in the soils
and sediments prior to disposal into the landfill unit.
Treatment ar«i air emission requirements relevant to hazardous
waste in 40 CFR 260-268 are not anticipated to be ARARs since no
listed hazardous wastes are known to have been disposed of in the
FWA. Also, leachate samples collected from sediments within
Fields Brook were found not to be hazardous waste by
characteristic. Notwithstanding the above determination
regarding placement or disposal, Tables 4-1 and 4-2 identifies
the ARARs to be followed and met during implementation of the
selected FWA remedy. While several of the regulations listed in
Tables 4-1 and 4-2 may not be applicable due in part to the above
placement and disposal determination, they are considered
relevant and appropriate and thus must be met.
Actions must be taken to minimize the destruction, loss, or
degradation of wetlands due to construction activities and the
final remedy, including possible compensation for wetlands that
will be adversely affected by the selected remedial action. A
detailed wetland mitigation plan is required prior to
construction of the remedy. An evaluation of the effects of the
excavation on the wetland hydrology will have to be conducted.
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This evaluation will be prepared based in part on input from the
U.S. Army Corps of Engineers and OEPA, and actions must be
implemented to provide for compliance with the
floodplain/floodway regulations. Various ARARs apply to this
issue, including Clean Water Act Section 404 and 401; Executive
Order 119990; 40 CFR 6, Appendix A; and 40 CFR 6.302(g). Actions
must be conducted as necessary to comply with the Clean Water
Act's Section 401 and 404 regulations, potentially including
investigations; modeling; alternative evaluation; creation of
compensatory storage for lost flood plain storage; use of
artificial channels combined with detention facilities or other
technologies to maintain stream capacity without increasing the
average velocity through the Site; excavation of soils and
sediments from the PWA and consolidation on-site; actions to
prevent or minimize negative impacts on the wetlands due to
construction activities and the final remedy; actions to minimize
the destruction, loss, or degradation of wetlands, including
compensation for wetlands that will be lost or adversely affected
by the selected remedial action; and other actions determined
necessary.
XI. KXPLANAT10N OF SIGNIFICANT CHANGES
There are no significant changes from the recommended alternative
described in the proposed plan.
XIX. STATUTORY DrTKUHNATIONS
U.S. EPA1s selected alternative provides the best balance of
trade-offs among alternatives with respect to the criteria used
to evaluate remedies. Based on the information available at this
time, therefore, U.S. EPA believes the selected alternative will
protect human health and the environment, will comply with ARARs,
would be cost-effective, and will utilize permanent solutions and
alternative treatment technologies or resource recovery
technologies to the maximum extent practicable. The selected
alternative will not satisfy the preference for treatment as a
principal element.
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ATTACHMENT 1 TO THE RECORD OP DECISION SUMMARY
RESPONSIVENESS SUMMARY
PLOpDPLAINS/WETLANDS AREA
RECORD OF DECISION
FIELDS BROOK SITE, ASHTABULA OHIO
PURPOSE
This responsiveness summary has been prepared to meet the
requirements of Sections 113 (JO (2) (B) (iy) and 117 (b) of the
Comprehensive Environmental Response, Compensation, and Liability
Act of 1986 (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act of 1986 (SARA), which requires the United
States Environmental Protection Agency (U.S. EPA) to respond to
the comments submitted, either written or oral presentations, on
the proposed plan for remedial action. All comments received by
U.S. EPA during the public comment period were considered in the
selection of the final remedial alternative for the FWA.
This document summarizes written and oral comments received
during the public comment period of November 17, 1996 to January
17, 1997. The comments have been paraphrased to efficiently
summarize them in this document. The public meeting was held at
7:00 p.m. on November 21, 1996 in the Auditorium of the Ashtabula
Campus of Kent State University in Ashtabula Ohio. A full
transcript of the public meeting, as well as all written comments
received during the public comment period and all site related
documents, are available for review at the Information
Repositories, at the following locations: l) Ashtabula County
Dist -let Library, 335 West 44th Street, Ashtabula, OH; and 2)
U.S. Environmental Protection Agency, Waste Management Division,
Records Center, 7th Floor, 77 West Jackson Blvd., Chicago, IL.
I. Camnanfcfl to 11/96 mx ProBoaati Plan;
Comment:: Implementation of the preferred alternative
(Alternative 7), nor any of the other alternatives presented in
the Proposed Plan, does not provide adequate long term protection
for the environment, including federal and State trust natural
resources. All of the alternatives leave significant residual
Site contamination in the floodplain and wetlands which will
continue to pose an unacceptable hazard and threat of injury to
trust natural resources therein, as well as to the natural
resources of Fields Brook and its receiving waters. The trustees
believe that the ecological risks identified in the Site
ecological risk assessments can and should be further reduced by
making significant improvements to the alternative remedial
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43
actions. These improvements include, but are not limited to,
environmentally sensitive adjustments of the proposed cleanup
goals, depth and area of excavation, habitat replacement and
monitoring.
Response: U.S. EPA believes that the response actions to be
conducted as proposed through Alternative 7 in the FWA soils
would protect the various populations of plants and animals which
exist or may exist along the floodplain area for this site, in
part by significantly reducing the short- and long-term risks to
ecological populations and reducing these population's potential
uptake of contamination via soil and food to acceptable levels of
exposure. Post-remediation hazard quotients (HQ's) for most
receptors of concern are below 1 for each contaminant regarding
exposure within the FWA, as indicated in the 10/96 FWA
Feasibility Study, Attachment 1. For all receptors of concern at
this site, the highest post-remediation HQ's calculated was below
5, which is within an acceptable range and within an order of
magnitude of the acceptable post-remediation objectives U.S. EPA
strives to achieve for all. ecological cleanups. . Further, the
planned monitoring is sufficient to determine both the
effectiveness of the selected remedy and the need for any further
action.
Also, Executive Orders 11988 (Floodplain Management) and 11990
(Protection of Wetlands) requires federal agencies to take
actions which minimize the potential harms to floodplains and
wetlands if the only practicable alternative requires
construction in these areas. Within the FWA FS, comparative
trade-offs between the destruction of habitat in place and the
reduction in-residual chemical concentrations which would result
if additi ual excavations occurred in the FWA were considered.
Alternative 7 offers the best balance between protectiveness,
cost effectiveness and minimization of. harm to the environment of
all alternatives, including the variation of Alternative 5
described above, and would be protective of both human healtu and
the environment.
Comment!; We disagree with the statement on page 3 that potential
risks to the environment would be addressed if risks to people
from ingestion of soil are addressed. The proposed cleanup goals
on page 4 for PCBs (6 ppm residential and 50 ppm industrial) and
HCBs (80 ppm residential and 200 ppm industrial) far exceed the
ecological cleanup goals (0.37 ppm PCB and 0.59 HCB) calculated
by U.S. EPA*Edison in Table 1 (column 3, page 4) of the October
1996 Baseline Ecological Risk Assessment Report (BERAR). In
addition, the Proposed Plan does not stipulate cleanup goals for
nine other Site contaminants, including mercury, lead, copper and
cadmium, all of which have ecological cleanup goals specified
(column 3, page 4) in the BERAR. Considering the great disparity
in cleanup goals presented in the BERAR and Proposed Plan, we can
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not discern how U.S. EPA used the BERAR to help "form the basis
for this proposed remediation plan" (bottom of column 2, page 2} .
Until the Proposed Plan cleanup goals are shown to have a firm
scientific link to the BERAR, we cannot agree with or support
them as being protective of the environment, including our trust
resources.
Reaponae; U.S. EPA's 1994 "Ecological Risk Assessment Guidance
for Superfund" specifies that risk management decisions should be
conducted by considering a range of risk estimates. This
guidance characterizes this range, with one -boundary to be set
based on conservative assumptions and one to be. set based on less
conservative, measured site-specific values. Exposure factors
are incorporated in the risk range development. The FWA remedy
is based on a range of cleanup goals as recommended in the
guidance. The Baseline Ecological Risk Assessment Report (BERAR)
identifies a range of values, appropriate as potential
remediation goals, for ecological receptors at the site. These
values differ primarily on the level of assumptions- used to
calculate parameters such as bioavailability, home range size,
etc. Values developed by U.S. EPA Edison are acknowledged to be
very conservative and in some cases are below known background
concentrations. The values identified in the BERAR were used in
conjunction with other information to develop clean-up goals
considered appropriate for the site for protection of human
health and the environment.
Specific clean-up goals for other contaminants such as lead,
copper and cadmium, were not specifically identified 'in the
Proposed Plan. Previous data analysis conducted as part of the
human health assessment, as well as an evaluation of residual
ecological risk values (HQ's), indicated that other contaminant
concentrations would be proportionally reduced as concentrations
of PCBs and HCBs are reduced through-adopt ion of the proposed
remedial action plan.
Comment: U.S. EPA (top of column 1, page 4) states that PCBs and
HCBs were the two compounds causing the majority of the human
health risk, and that if the cleanup activities removed the
elevated areas of PCB and HCB soil contamination, then the
cleanup would also remove other COCs because these exist where
elevated levels of PCBs and HCBs exist. Although this finding is
made in the context of human health, the U.S. EPA later states
(middle of column 2, page 4) that the cleanup actions will also
protect the environment. Review of the FWA data indicates
arsenic concentrations at sample points outside the proposed
cleanup areas which exceed the PRPs ecological cleanup goals 38
times. Clearly, this Site.contaminant, and possibly others will
not be affected by implementing the preferred remedy or any of
the alternatives, and will continue to pose ecological risk.
Therefore, the proposed remediation of PCBs and HCBs will not
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45
simultaneously remove or contain elevated concentrations of all
of the other COCs.
Response: In evaluating remedial alternatives, U.S. EPA
considered residual risks associated with all chemicals of
potential concern, including arsenic. Arsenic is one contaminant
which has cleanup goals in the BERAR below background levels at
the site. Arsenic is present in the watershed as a natural
constituent of the local geology at levels at which exposure
risks approximate those found in background areas. Since U.S.
EPA generally does not require cleanup of contaminants below
background levels at sites, the arsenic cleanup goal for the FWA
ia set at the background level for the FWA. which ia 27 ppm.
Residual risk numbers were generated assuming area use factors of
1 (100% of exposure being on-site) for a number of receptors,
including the shrew, which had the highest residual arsenic
exposure risks (BERAR, page 34) . However, as indicated in the
comment response above, the highest post-remediation HQ's
calculated for all COCs for all receptors of concern at this site
was below 5, which is within an acceptable range and within an
order of magnitude of the acceptable post-remediation objectives
U.S. EPA strives to achieve for all ecological cleanups.
Also, it is clear that the dominant risk in the FWA to both human
and ecological receptors is from PCB and HCB, and that the
significant levels of all other COCs.exist where elevated levels
of PCBs and HCB exist, as indicated in part by the 12/11/96 "FWA
Delineation Sampling Maps" deliverable from Woodward Clyde which
has been included in the Administrative Record. Based on a
review of the data, U.S. EPA has found that if a remedial cleanup
to the HCB and PCB FWA CUGs on average throughout each exposure
unit occurs, the low levels of all other contaminatiort and other
COCs remaining in the FWA after cleanup is completed would be
protective of both human health and the environment for each
exposure unit.
Comment • Page 5, Summary of Alternatives - bottom of 2nd
paragraph and Page 8, item D) Remedial Activity Locations -
middle of second paragraph: The PRPs are not in agreement with
the FWA delineation sampling program as described in the Proposed
Plan. The PRPs described a delineation program to U.S. EPA that
involved further delineating existing response areas developed in
the FS. The PRPs did not propose to collect additional samples
at fifty-foot intervals in the entire FWA.
The text indicates that soil sampling data will be collected at
fifty-foot intervals in the floodplain during delineation
sampling programs. This could be interpreted to mean across the
entire Floodplain/Wetland Area. The PRPs have concerns that U.S.
EPA has misinterpreted the intent of the delineation sampling
program discussed during the September 26, 1996 meeting and as
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46
described in Section 4.5 of the FWA FS provided to U.S. EPA in
October 1996. As a general comment, the PRPs do not intend to
collect soil samples in the entire FWA at fifty-foot intervals
across the entire FWA, for the following reasons:
During earlier phases of the investigation more than 250
floodplain samples have been collected in the five FEUs. These
sampling programs were approved by U.S. EPA; in order to
characterize the FWA, develop remedial alternatives and satisfy
Remedial Investigation (RI) objectives regarding the nature and
extent of the 11 COCs. The previous sampling programs were based
on systematic sampling along transects and spatially distributed
so as to satisfy U.S. EPA concerns regarding definition of
locations of COC concentrations on both sides of Fields Brook.
Grid sampling across the entire FWA is not necessary. It is a
waste of financial resources.
If grid sampling were to be considered, it should have occurred
in 1993-1994 when the RI activities were in progress and not at
the design phase of the project and would have replaced the
systematic sampling program (which was approved by U.S. EPA and
implemented by the PRPs).
Since the FS has been completed based on the approved systematic
sampling program, and response areas identified, it is
appropriate at this time to conduct a delineation sampling
program to support the final FWA design. The purpose of the
delineation sampling program is to properly define the response
areas that have been developed in the FWA FS for cover and
excavation and substantially reduce the uncertainty that any
significant. contaminated areas have been missed. The FWA FS
described that the delineation sampling program was intended to
further delineate current response area boundaries and sample in
areas where data points are widely spread. The delineation
sampling program intended to be conducted by the PRPs consisted
of approximately 200 samples located within the FWA. A fifty-
foot grid would be used to identify possible sampling locations,
in order to better define response boundaries, fill in data gaps,
and to develop outlines for use in preparing design drawings.
U.S. EPA requested that sampling maps be submitted prior to field
work in order to review proposed sampling locations. The
delineation program and O&M sampling proposed by the PRPs would
supplement existing data and would be sufficient and protective
for the proposed alternative.
Response: U.S. EPA has thoroughly considered this issue, and
finds that to provide better confidence in understanding the
extent of contamination throughout the FWA, and to provide
assurance that the response areas are properly and completely
defined, To implement the remedy, additional delineation sampling
will be conducted prior to the beginning of remedial construction
activities to ensure that the response areas are properly
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47
defined. In each FWA exposure unit prior to the beginning of
construction, one PCB sample must be taken and analyzed in every
2,500 square feet residential FWA area (i.e., one sample every
fifty feet along all north-south and east-west directions) , and
in all but twelve 2,500 square feet industrial FWA areas, which
are downgradient or downstream of the FEUS CUG exceedence areas.
The twelve industrial FWA areas which are not planned to be
sampled in this delineation effort are located near or along the
outer edge of industrial floodplain areas where CUG exceedences
were not previously indicated. Eight of these locations are in
FEU 6 along the southern edge of the FWA in fenced-in areas of
the RMI-Extrusion property, and four of these locations are in
FEU 8 on the northeast edge of the FWA. In addition, HCB
delineation samples are required to be taken around proposed
response areas in FEU's 4 and 8 which were developed due to
elevated HCB sampling results. U.S. EPA finds it acceptable to
not do further delineation sampling in existing areas already
slated for response actions.
This degree of delineation is needed in part because
contamination distribution is not even and consistent throughout
the FWA. Review of the existing FWA data distribution along
various FWA outer edge areas, particularly in FEU4, has
discovered incidences of contamination at the 100 year floodplain
line above the cleanup goals. In rare cases, the data along the
outer edge of the FWA is higher in concentration than in FWA
areas between the outer edge and the brook.
U.S. EPA is concerned that by not doing the SO' grid spacings in
various large industrial areas not currently slated for response,
the results will be unacceotably biased towards a lessening of
the response areas. Furtl.jr, such sampling permits a lessening
of the degree of future O&M chemical monitoring to be conducted
in part due to the expectation that the extent of contamination
would be determined through 50' grid sampling in all FWA areas.
Comment: Page 7, item B), Landfill Requirements: The
description of the on-site landfill should be referred to as the
on-site consolidation area, to be consistent with the FS text and
language used to describe this area by the PRPs.
Response; The on-site landfill may be described either as a
landfill or a consolidation area, and inconsistencies regarding
the reference to this unit would not change the components or
requirements for the installation or operation and maintenance of
this unit. Thus, either of the two terms may be acceptably used
interchangeably, and no text change is required.
Comment;^ Page 7, item B) , Landfill Requirements: -During the
September 26, 1996 meeting with the PRPs and U.S. EPA, the on-
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48
site consolidation area was described as a storage area that
would contain materials from the following areas of the Fields
Brook site: a) Soil excavated from FWA response areas; b)
Sediment excavated from Fields Brook as part of Sediment Operable
Unit (SOU) remediation; and c) Excavated haul road material from
construction of FWA and SOU remedial areas.
Responge; U.S. EPA would find it acceptable to place excavated
sediment from Fields Brook as part of Sediment Operable Unit
(SOU) remediation and excavated haul road material from
construction of FWA ?nd SOU remedial areas into the on-site
landfill to be constructed for the disposal of FWA soils.
However, these excavated materials to be placed into the landfill
must be shown not to be a "hazardous waste* as defined by U.S.
EPA's RCRA program (i.e., the source area soils must not fail
RCRA's 'Toxic Characteristic Leaching Procedure' testing).
Comment; U.S. EPA should consider the following variation to
Alternative 5 (top of column 3, page 5): Excavation, Backfill,
and On-Site Disposal. If disposal occurs in the "On-site
consolidation area" (bottom of column 1, page 6), costs would be
reduced from the $19.0 million cost of Alternative 5 by perhaps
as much as $7.0 million. If this cost reduction is correct, the
cost of this variation to Alternative S would be approximately
$12.0 million. This figure is far more cost-effective than
Alternative 5 and much closer to the $6.9 million cost for
Alternative 7. The main advantage to this variation to
Alternative 5 is better protection for the environment through
increased removal of contaminated soil (13,200 additional cubic
yards would be excavated over Alternative 7, in accordance with
the proposed cleanup criteria and excavation depth) from the FWA.
Response: U.S. EPA agrees that on-site disposal is generally
more cost effective than off-site disposal, and agree in
principle that the cost savings to Alternative 5 as noted above
may be likely. However, the relatively low level of potential
increased protectiveness provided by the increased FWA soil
excavation provided by this variation of Alternative 5 does not
offset the increased costs required to implement this alternative
over the cost of Alternative 7 (i.e., at least $5.1 million
increased costs). Because the highest post-remediation HQ's
calculated were below 5 if Alternative 7 is implemented, and
because the cleanup goals and remedial action objectives would be
met or exceeded for human health, Alternative 7 offers the best
balance between protectiveness and cost effectiveness of all
alternatives, including the variation of Alternative 5 described
above. Also, the additional damage to the wetlands that would
occur under the variation to Alternative 5 described above also
weighs against this alternative.
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49
Comment: We believe it is misleading to characterize (bottom of
column 2, page 4) post-remediation residual PCB contamination as
an average (1 ppm for the. residential exposure units and 6 to 8
ppm for the industrial exposure- units). The residual PCB
contamination should be characterized as a range of the lowest
existing concentration up to 6 ppm for residential and 50 ppm for
industrial. Since the post-remedial PCB concentrations would
greatly exceed U.S. EPA-Edison's BERAR ecological cleanup goal of
0.37 ppm, we can not agree with U.S. EPA (middle of column 3,
page 4) that the Proposed Plan cleanup goals represent acceptable
levels of exposure or will provide for the future health and
viability of ecological populations.
iteaponflg; it was considered appropriate to characterize post-
remediation residual concentrations as averages based on an
understanding of most post-remediation exposure scenarios. In
many cases, including both human and ecological receptors, post-
remediation exposure is likely to occur over a certain unit area
over the site. The typical home range of many organisms is such
that they are likely to be exposed to a range of concentrations
which may be higher in some locations and lower in others. As a
result, exposure ia expected to be represented by an average
concentration within the exposure unit. For some species such as
field mice, however, exposure levels may represent more site-
specific concentrations. For these species, however, exposure to
higher concentrations would occur to only a fraction of the total
population of the species inhabiting the Fields Brook site.
Comment; We disagree with U.S. EPA's conclusion (page 4, column
2, paragraph 3, and column 3, paragraph 3) that the residual
contaminant concentrations follow? g remediation would
necessarily pose acceptable levels of exposure to ecological
receptors and thereby protect the environment. Much of the
floodplain lies within the riparian zone of Fields Brook and is
closely associated with the aquatic environment. Yet the
ecological risk assessments completed for the Site did not
include a full assessment of the aquatic environment. Biotic
sampling, such as fish tissue analysis for COCs, was not
conducted to properly evaluate the risk to aquatic organisms and
the risk to terrestrial receptors such as the highly piscivorous
mink and great blue heron. It is, therefore, imperative that
U.S. EPA require post-remedial biological monitoring of the
aquatic and terrestrial environments in order to provide a
scientific basis for verifying the presumed effectiveness of the
proposed remedy. Until actual measurements of biotic systems are
conducted, the trustees do not believe that U.S. EPA will be able
to adequately demonstrate whether the proposed remedy is
effective in protecting the environment.
The proposed post-remediation sampling (middle of column 3, page
7) is currently limited to chemical sampling and analysis for a
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50
period of 5 years. Considering that the proposed cleanup goals
for PCBs (6 ppm. residential and 50 ppm industrial) greatly exceed
the ecological cleanup goals recommended in the BERAR (U.S.
EPA-Edison 0.37 ppm and the PRPs Aroclor 1260 0.35 ppm), and that
several of the COCs bioconcentrate and/or 'biomagnify in
ecological food chains (e.g., PCB, HCB, cadmium, copper,
mercury)• we recommend that U.S. EPA require sampling and
analysis of COCs in floodplain flora and fauna as part of the
post-sampling requirements. We also strongly recommend that U.S.
EPA extend the monitoring period at least 20 years in order to
verify the long term environmental protectiveness of the remedy.
This length of time is reasonable, considering that PCBs may
persist for 75 years or longer.
Table 1 of the BERAR (columns 2 and 3, page 4) lists ecological
clean-up goals for the following Site contaminants that are not
included in post-remediation sampling (middle of column 3, page
7): fluoranthene, napthalene, phenanthrene, hexachlorethane,
cadmium, copper, lead, mercury and zinc. Please explain why
these contaminants are not included in post-remediation sampling.
In addition, HCB should also be sampled along with PCBs in years
1 through 4 because the cleanup and protectiveness of the
preferred remedy is based on the assumption (page 4) that if the
cleanup activities removed the elevated areas of PCB and HCB soil
contamination, then the cleanup would also remove other COCs in
the floodplain area because this is where the other COCs exist.
Response: It is acknowledged that a full assessment of the
aquatic environment of Fields Brook, which has only developed
since the brook became a continuous stream due to industrial
discharges, was not completed. To help ensure protectiveness of
the aquatic'environment, a separate focused ecological risk
assessment of the brook sediment was recently prepared by U.S.
EPA; this assessment estimates post-remediation risk levels to
ecological receptors such as mink who are or may be exposed to
the brook. This focused assessment does recognize that the post-
remediation average concentration chronic hazard quotient (HQ)
calculations using the above noted cleanup goals indicate that
there may be several species with HQ exceedences of 1, and thus
the potential still exists that there is a potential ecological
residual risk using the calculated cleanup goals.
However, U.S. EPA believes that the response actions to be
conducted based on cleanup of both the FWA soils and brook
sediments based on the cleanup goals set for the brook sediment
and for the FWA soils would protect the various populations of
plants and animals which exist or may exist within the brook and
along the floodplain area for this site. The response actions
would reduce the short- and long-term risks to ecological
populations and reduce these population's potential uptake of
contamination via soil and food to acceptable levels of exposure.
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Regarding the brook cleanup, EPA's focused ecological risk
assessment of the brook sediment indicated that post-remediation
HQ's for most receptors of concern (ROC) are below l for each
contaminant regarding exposure within the FWA. There were two
contaminants which had post-remediation HQ exceedences of l for
brook sediment for mink; for PCBs in FEU6, the HQ is
approximately 13, and for HCB, the HQ is approximately 6. U.S.
EPA believes that the response actions to be conducted in FWA
soils and brook sediments would protect mink, in part because the
typical home range of mink is such that they would be exposed to
an area encompassing several exposure units, and would also feed
from areas within both the brook and FWA, as well as outside of
this area. As a result, exposure to higher concentrations would
occur in only a fraction of the total food intake for mink, and
the population of the species inhabiting the Fields Brook site
would be protected.
Also, the surface sediments of the brook will be diluted with
cleaner bedload stream sediments over time after the source area,
brook and FWA remediations occur, and this will significantly
reduce the average residual sediment surface concentrations, for
several reasons. The net average suspended sediment
concentrations coming from source properties during storm events
after source remediation occurs will be well below CUGs, and
since the industrial properties comprise only approximately ten
percent of the entire brook watershed, the net suspended sediment
concentrations from the brook watershed will likely be at or near
non-detect levels for all contaminants of concern. Further, the
upstream half of Fields Brook was never contaminated with
significant levels of COCs, and future storms will move clean,
non-contaminated sediments down from these upstream areas and
cover up any residual low level contamina1 'on left in brook
sediments after.remediation. Thus, after crook remediation, the
net average residual concentrations in brook sediments which
could be released during future storms are expected to be well
below the CUGs.
Also, as discussed in earlier comment responses, U.S. EPA
believes that the FWA remedial response actions to be conducted
would protect the various populations of plants and animals which
exist or may exist along the FWA, in part because the FWA's post-
remediation HQ's for mink are below 1 for each COC, below 5 for
all other ROCs, which is within an acceptable range and within an
order of magnitude of the acceptable post-remediation objectives
U.S. EPA strives to achieve for all ecological cleanups. Thus,
U.S. EPA feels that sediments will be remediated to levels
protective of aquatic receptors and wetland and terrestrial
receptors which might utilize the aquatic ecosystem.
Current post-remediation monitoring plans are to include sampling
of soil and sediment within the Floodplain/Wetland Area. This
level of monitoring is appropriate to evaluate site conditions
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52
following clean-up. As with many baseline risk assessments,
results of chemical analysis can be used in conjunction with
acceptable exposure models to estimate potential risk levels to
ecological receptors at the site.
The range of post-remediation chemicals to be monitored do not
need to be increased at this time, because previous data analysis
conducted as part of the human health assessment, as well as an
evaluation of residual ecological risk values (HQ's), indicated
that other contaminant concentrations would be proportionally
reduced as concentrations of PCBs and HCBs are reduced through
adopt .ton of the proposed remedial action plan. The eleven key
chemicals of concern, and primarily PCBs and HCB, will be
analyzed yearly for five years after cleanup, and these
contaminants are the key indicators regarding whether the FWA
remedy remains protective and whether chemical concentrations are
increasing or not in the FWA after cleanup.
Regarding duration of sampling, U.S. EPA's current.recommendation
is for post-remediation monitoring to extend for a period of 5
years. At the end of the 5 year period, a re-evaluation will be
made as to the appropriateness of extending the monitoring time
period. Post-remediation monitoring .will not necessarily
terminate after 5 years.
Comment: The post-remediation sampling does not provide action
levels that will trigger additional remediation. U.S. EPA should
establish such action levels for both chemical and biological
sampling in concert with the trustees.
Response: Action-levels which may trigger additional remediation
have, not been identified at this time. Appropriate action levels
will be determined in the future as -monitoring is conducted. In
this way, action levels can be developed which incorporate the
most recent toxicity information available for the contaminant
and/or ecological receptor of concern. New data on contaminant
affects is continuously being developed, which can be applied in
establishing appropriate action levels. Establishment of action
levels now, without the proper information, would be meaningless
and may limit application of information that may become
available in the future.•
Comment:; The soil cover process option component of Alternative
7, as well as alternatives 2 through 6, is referred to in the
Proposed Plan and Section 6.0 of the October 1996 Final
Feasibility Study as providing a "permanent remedy." However,
this option would leave significant concentrations of
contaminants- in-place which could potentially become exposed to
terrestrial receptors as well as recontaminate the. stream
channel. In Alternative 7, only six inches of cover will be
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53
placed over PCB-contaminated soils ranging from 6 to 30 ppm.
According to Table 5-1 of the Feasibility Study, the Alternative
7 cover areas comprise 160,000 square feet or approximately 3.7
acres. Since beaver dam induced stream re-routing has been
documented in several exposure units at the Fields Brook Site,
there is a very real potential for either beaver dam induced
stream re-routing or future meanders to cut through areas of the
floodplain containing soil that is contaminated above levels that
are considered protective of the aquatic environment. In
addition, the COCs may be brought to the surface by fallen trees,
wet periods, storm events and burrowing animals. Also, adding a
six-inch soil cover may inhibit the growth of wetland vegetation.
Considering that the zone of biological activity is generally
agreed to be 12 inches, and that the Alternative 7 cover areas
would be contained in a dynamic environment subject to physical
and biological perturbations, we do not see how the U.S. EPA
could determine with confidence that the 6-inch cover meets the
criterion for long term effectiveness and permanence. The
trustees are doubtful that Alternative 7 fully meets the
evaluation criterion for long-term effectiveness and permanence
due to the dynamic factors affecting the Site location and
stability.
Response; A soil cover option for portions of the Fields Brook
Floodplain Area is proposed as part of the plan for the site, and
would occur only in portions of the downstream half of the FWA
remediation area. This option will be employed to areas with PCB
concentrations ranging from 6 to 30 ppm. Concentrations of
contaminants which may exist under the clean cover layer might
eventually reach the surface, but the residual surface levels
would likely be lower than the concentrations of the soil under
the soil cover due to soil mixing which may be expected to occur
due to freeze/thaw, earthworm turnover and other phenomenon. As
a result overall
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the site. Issues relevant to wetland impacts are to be addressed
in the Section 404/401 submittal that is a component of the 90%
Design Phase. The potential for cover areas to reduce the
wetland character of the floodplain vegetation has been accounted
for in the overall remedy. Wetland character will be retained to
the extent possible.
Comment! The description for Alternative 7, as well as
Alternatives 2 through 6, state that wetlands mitigation will be
considered. He request that the U.S. EPA establish wetlands
mitigation as a requirement based on ARAR compliance under the
Clean Water Act. There is no doubt that, the activities being
discussed, i.e., vegetative clearing, excavation, filling, road
building, use of heavy equipment, will harm wetlands.
Consequently, we believe U.S. EPA should determine the amount,
type, and location of replacement wetlands.
Table 5-1 of the October 17, 1996 Feasibility Study indicates
that Alternative 7 affects 572,000 square .feet of response area
(excavation and cover area). We believe that most, if not all of
this acreage (13.13 acres) is wetlands. However, U.S. EPA should
confirm the amount of wetlands being impacted by excavation and
cover, and provide a breakdown of acreage by wetland types. The
amount and types of wetlands affected by the proposed access road
should similarly be determined. We recommend that the U.S. EPA
require a minimum of 1.5 to 2.0 acre replacement for each acre of
affected wetland. The exact amount of replacement within this
range should be determined by the trustees and U.S. EPA based on
our consideration of wetland value, scarcity and time needed to
restore wetland functions. The replacement wetlands should be
located within the Fields Brook, or a nearby, watershed, and
preferably in one location.
We are concerned about the design and longevity of the proposed
temporary access road. This structure could interfere with
floodplain and wetland hydrology, become a source or cause of
erosion and contamination, disrupt or interfere with wildlife
movements, and degrade or destroy adjacent wetlands. We
recommend that U.S. EPA coordinate the remedial design of this
road with the trustees.
Response: Section 404/401 of the Clean Water Act is an
identified ARAR for the site. Issues relevant to wetland impacts
including mitigation needs and roadway impacts will be addressed
in the Section 404/401 submittal that is a component of the 90%
Design Phase. The State of Ohio will be involved in this review,
in part because it currently has the lead role in managing the
401 program, and the State can coordinate reviews directly with
the other trustees when the 404/401 review occurs.
Also, this comment appears to assume that the remedy will
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eliminate wetlands in place. This is not true. Wetland
character will be present in the post-remedy environment of the
FWA, and will be encouraged by (as documented in the FS report)
the use of hydric compatible soils for backfill and in the
replanting program.
Comment; Part of the plan for remediation of the FWA is to leave
trees greater than twelve inches diameter at basal height and
backfilling around them with six inches deep clean soil. My
experience is that four inches of backfill over root zones is
sufficient to cause tree decline, although not necessar.ily
immediately. It is my experience that whenever filling is
planned around existing trees, it is more economical to remove
all existing trees prior to placing the backfill. This would be
less costly to do now vs. five years from now, when installation
and replacement costs are taken into account, and in addition the
replacement tree will not have been retarded for five years.
Response; Although it is recognized that the potential for some
tree death exists for the areas to receive soil cover, there
appears to be conflicting data on the level of potential risk to
trees. For example, one reference (Harris, R. H., 1992,
Arboriculture; Integrated Management of Landpeape Treea. Shmhg
and vines. Prentice Hall) states that many species of trees are
capable of surviving burial of up to several feet of material.
Eventually the root system grows up into the fill material or,
depending upon the species, new roots may grow from the original
root collar at the base of the tree or from the trunk itself.
The concern is that the roots must.receive adequate oxygen and
not be subjected to buildup of carbon dioxide. This reference
also recommends that compaction of the fill around the tr*»es
should be avoided, and suggests using equipment with a
retractable boom so that the equipment stays outside the. dripline
of the trees if feasible. This recommendation will be
incorporated into the ROL for the placement of six inches of
clean soil cover in areas around all trees to be left standing in
areas to be covered.
Also, potential tree deaths resulting from the cover option are
to be addressed in the planned operation and maintenance (O&M)
procedures for the. site. The health of the large trees left in
the FWA in cover areas will be monitored on a regular basis after
the cleanup occurs in part to determine if the trees are
stressed. If stress is indicated, steps may be taken during O&M
to modify the soil cover to protect the tree. If the trees
cannot be saved, the trees will be removed. Trees which die
following remediation are to be replaced, albeit with trees from
nurseries which have not yet reached maturity. Natural
recruitment of trees in cover areas, as well as the planting of
trees and shrubs, will also occur following placement of the
cover.
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Comment: U.S. EPA should emphasize function vs. character when
conducting replacement vegetation. Herbaceous reed, rush, sedge
and grass species thrive in hydric soils, control erosion, and
enhance water infiltration, and can be first grown on 100%
cocofibre mats which can then be placed down into the FWA as sod
thereby providing almost instantaneous erosion control which
would extend the planting window. If aesthetic concerns demand
tree character, woody shrubs such as cornus stolonifra, trees
such as acer rubrum and/or fraxinus pennsylvanica lanceolata are
riparian species that also have an attractive appearance. These
tree species .can be successfully grown, in the bank zone, but
should be avoided in the splash zone.
Response! Future revegetation of areas disturbed during remedial
activities will include use of erosion mats and regrowth of
native vegetation. Additional information on revegetation of the
Floodplain/Wetland Area, including which species will be
replanted to achieve the goal of revegetation of native species
in disturbed areas, will be addressed in a separate submittal
during design of the FWA remedy.
Commen.t: Alternatives 5 and 6 (all excavation to 12-inch depth)
seem to offer greater long term effectiveness and permanence than
Alternative. 7, but even these alternatives would not provide full
long term protection. U.S. EPA confirms (Questions and Answers
No. 20, Fields Brook Superfund Site Information Availability
Session and Public Meeting, September 26, 1996) the contaminated
soils below the 12-inch depth could be exposed by erosion during
flooding events. Further modifications of Alternatives 5 through
7 would be needed to achieve a greater degree of long term
effectiveness. These changes include cleanup goals that provide
a greater reduction in environmental, risk and excavation to depth
of contamination. The extent of excavation should be driven by
compliance to the cleanup level established for the Site and
should not be limited by an arbitrary depth. By failing to
excavate the full extent of contamination exceeding cleanup
levels, the preferred and alternative remedies do not provide a
reasonable assurance of protectiveness. Current data gaps, with
respect to depth of contamination, should be addressed during the
proposed design delineation sampling.
Response: Of the 23 deep soil samples taken between one-to-two
feet from the surface in the FWA, only two samples indicated
levels of any contamination above the acceptable Cleanup Goal
levels. These two locations are in the FWA soils between
Columbus Avenue and East 16th Street. The levels of
contamination at these locations are only slightly above the
cleanup goal levels and in these two locations the surface soils
will be covered with six inches of clean soil. Since the FWA is
primarily a depositional area, contamination has been left in
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almost all areas within the top one foot of surface soils. Thus,
excavations below one foot are not required to achieve a
protective remedy. Further, O&M for the remedy and the planned
monitoring is sufficient to address these concerns and prevent or
repair the effects of significant erosion. Also, any buried
contamination that would become exposed at the surface would not
be at its sub-surface concentration but at a lower level due to
dilution with clean soil.
Comment; Confining pollutants does not get rid of them. Shallow
wells in our area have nitrate contents of up to 60 ppm which we
attribute to the fertilizers used by the numerous nurseries in
the area. I favor Alternative #6 (incineration of wastes).
Response; incineration of the lower-level contaminated soils
would be very expensive and would not be cost effective. U.S.
EPA'has considered the likelihood of direct exposure by people to
contaminated soils below the 6 inches of clean soil;, and believes
that the cover activities in the residential area of the FWA
combined with the excavation activities will provide a protective
remedy. The primary route of exposure to soils in the FWA is
direct ingestion of soils, and a soil cover will effectively
contain the low-level contaminated soils in place and prevent
surfacing of the contamination. The City of Ashtabula provides
drinking water to all residents in Ashtabula with water taken
directly from Lake Erie, and this water is tested regularly and
has not shown any exceedences of drinking water standards. In
addition, nitrate is not one of the chemicals of concern within
the FWA soils and incineration of nitrate contamination is not
necessary to provide for protection to human health and the
environment.
Comment; U.S. EPA's proposed FWA remedial action involves
construction of an on-site landfill to be located on one of the
properties within the Fields Brook watershed. In addition to
placement of certain FWA soils into this landfill, it is
requested that U.S. EPA also allow placement of certain excavated
soils from Source Control areas of the Fields Brook site into the
on-site landfill (e.g., soils/sediment containing PCB
concentrations greater than SO ppm originating from the ACME
property). The placement of this material into the on-site
landfill would be an alternative to transporting the material to
an off-site facility.
Response; U.S. EPA would find it acceptable to place certain
excavated soils from Source Control areas of the Fields Brook
site into the on-site landfill to be constructed for the disposal
of FWA soils. However, the source control soils to be placed
into the landfill must be shown not to be a "hazardous waste" as
defined by U.S. EPA's RCRA program (i.e., the source area soils
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must not fail RCRA's 'Toxic Characteristic Leaching Procedure1
testing). Also, the parties who will be constructing the FWA
landfill must agree to accept these soils.
B) Verbal Comments to the Proposed Plan From 11/21/96 Public
Meeting
Comment: Why are we going to clean up Fields Brook and not clean
up the Ashtabula River? Fields Brook flows into the Ashtabula
River, and the River flows into the Lake, where the Ohio Water
Works pulls water from an outlet. Because the chemical
contamination has been in both the brook sediments and FWA soils
for approximately fifty years since the second world war, the
majority of the contamination has already leached out of the
soils and sediments. However, when someone starts to move and
churn up the sediments and soils, there will be significant
releases of contamination, particularly during rainfall events.
These releases would be unacceptable.
Also. Separate Written Comment: During times of northeasterly
winds, there is a significant increase in raw water turbidity,
total coliform bacteria, and chlorine demand in the raw water
intakes located west of the mouth of the Ashtabula River in Lake
Erie which supply drinking water to the City of Ashtabula. This
degradation in raw water quality is attributable, in whole or in
part, to the influence of the Ashtabula River. The company
supplying water to the City of Ashtabula has monitored for
organics in the raw water for over a decade. While organics such
as PCBs, PAHs and HCB have never been detected in the raw water
at the treatment plan, such monitoring i requested to be
conducted at the mouth of Fields Brook aud at the mouth of the
Ashtabula River prior to, during, and for a reasonable period of
time after completion of the Fields Brook remediation project to
assure that the safety and quality of the City of Ashtabula's
water supply is maintained in an uninterrupted manner.
Representatives of U.S. EPA, OEPA, the City and the Water Company
should meet to discuss monitoring locations and frequencies.
Response: Water from Fields Brook is not considered a source of
drinking water in the area. Contamination from the Site has not
been found in the City of Ashtabula's drinking water. Surface
water samples were collected from the brook, river and harbor
areas in the past. As a result of this sampling, it was
determined that the City of Ashtabula's water supply in Lake Erie
is not being contaminated by discharges from the Fields Brook.
The surface water sampling conducted within the Ashtabula River
in 1991 and in earlier years did indicate a few exceedences of
chemicals regulated as U.S. EPA drinking water standards;
however, no exceedences significantly above the drinking water
standards were indicated. Also, since at least 1972, all
operating industries which discharged a significant amount of
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water to Fields Brook or the Ashtabula River were and are
required to test their discharge water frequently (e.g., usually
either monthly or weekly,, sometimes daily or continuously) and
treat their discharges if necessary to ensure that the water is
clean.
The City of Ashtabula receives its water from an area of Lake
Erie which is almost always not impacted by Fields Brook and the
Ashtabula River; the only potential impacts may occur during
times of infrequent northeasterly winds. Public water systems of
the size of Ashtabula's are required to monitor and test for
various contaminants including most of the contaminants found in
the sediments and soils in and around Fields Brook. This testing
is done every three months. None of these monitoring samples
have found any contamination associated with the Fields Brook
Site. To help ensure protectiveness, the PRP group conducting
work at the Site also tested the City's drinking water in 1992 at
the intake point in Lake Erie and found no contamination in the
water. Therefore, the City's drinking water was not found to be
impacted by the Fields Brook Site, and is considered safe.
The proposed cleanup alternatives for the brook sediments and FWA
soils will require collection and treatment of any wastewater
generated during cleanup operations. The treatment requirements
of this wastewater will be based in part on Ohio EPA's surface
water discharge permitting requirements, and discharges will be
regulated to ensure that the waters have been treated
sufficiently to assure protection of human health and the
environment. During construction activities, the soils and
sediment areas of the brook and FWA which will be disturbed will
be covered every evening. Actions will be taken to help ensure
that releases of contamination will not occur, such as covering
of disturbance areas with tarps, installation of silt fences in
downgradient areas of brook construction to prevent releases of
suspended sediments, and .a three day limit for any brook sediment
areas to be left exposed during stream reiouting. Also, the
brook and FWA remedies will be conducted in segregated parts of
approximately 100-200 foot lengths, to help ensure that large
areas of disturbed soils are not left unprotected during
rainstorms which may occur. Work will also stop if releases are
indicated or if a rainstorm appears imminent. U.S. EPA believes
these activities are sufficient to confirm the continuing lack of
impact of dischargers from the Field Brook on the drinking water
supply for the City of Ashtabula. Thus, additional sampling is
not needed.
Regarding cleanup activities in the River, contamination found in
Fields Brook sediment has been shown to have migrated into the
river sediment and it may be necessary and appropriate to
remediate those contaminants as part of the' Fields Brook site
Superfund remediation activities. A Public/Private Partnership
known as the Ashtabula River Partnership (ARP) involving U.S.
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EPA, U.S. Array Corps of Engineers, the State, City, local groups,
local industries, local businesses, the County, and public
officials was formally initiated in 1/94. The overall ARP goals
are to restore beneficial uses by removing the River's
contaminated sediments. The Superfund program is monitoring
progress of the ARP, and if the ARP develops firm plans to
address the contaminated sediments, then U.S. EPA may suspend or
stop its Superfund-related studies associated with the Ashtabula
River.
Comment: Sediment was recently taken out of the Ashtabula River
and dumped into a landfill in the Township area. The landfill is
still there. le there going to be a new landfill located near
that landfill? Doctors have said that the environmental air that
we breathe can be coming from this particular area. The proposed
location for the new landfill is near residences/ and we don't
want the landfill in our area or in the City of Ashtabula.
Ashtabula County has become a dumping ground for toxic waste.
PCB's have been dumped already on West 38th Street, and in the
east side area.
Response; it is generally most cost-effective and
environmentally safe to treat wastes on the site where the wastes
were deposited or generated. For the Fields Brook site, this
will be within the watershed area of Fields Brook. U.S. EPA
considered all possible areas within the industrialized areas of
the Fields Brook watershed as the preferred location for the
landfill, since most of the residences and schools are separated
from these areas. After considering all possible areas, U.S. EPA
narrowed potential landfill locations to the Detrex, ACME and RMI
Sodium facilities. The Detrex facility has a significant
groundwater plume of contamination, and the ACME facility has
significant amounts of debris and other contamination throughout
the property, which would create difficulties with locating a
landfill. The RMI Sodium property location would generally meet
or exceed regulations for siting landfills. This location will
provide at least a 2000 foot buffer from most of the residences
in Ashtabula, and would not involve any construction in wetlands,
areas of high groundwater, or surface water bodies. For these
reasons, the preferred location at this time for the on-site
landfill for the FWA soils to be excavated is on the RMI-Sodium
facility, which is approximately one mile west of the landfill
facility where the Ashtabula River sediments which were dredged
in 1994 were brought.
The transport of sediments and FWA soils will be required to be
conducted in a safe and clean manner. The trucks will have
covers which will prevent dust releases or spillages during
transport from the brook and FWA area.
Once landfilling occurs, dredged soils and sediments generally do
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not release a sufficient amount of gas to cause a human health
concern. Once all of the dredged sediments and soils are brought
to the landfill, the landfill is closed and covered with a thick
layer of clean soil in part to prevent rainwater from entering
the fill area. The landfill will also have a plastic layer
incorporated within the cover, have a grass surface, have a fence
surrounding the facility and have a series of plastic liners for
leachate detection and collection. An anaerobic environment
(i.e., without oxygen) will be created within the landfill which
will hinder the release of gases from the fill material. The
landfill will be monitored to assure it remains protective of
human health and the environment. While there would be eventual
release of gases which may build up over time within the dredged
sediments, the rate of release is very low and thus would not
likely cause a health problem to anyone who may be walking near
the landfill. Also, the greatest chance of releases of gases
from the dredged sediments is during excavation .and
transportation, because this is when the sediments are most
exposed to the ambient air. During the Ashtabula River dredging
of 1994, the air was tested around all construction activity
areas in order to determine whether any hazardous substances were
being released, and this testing did not indicate that any levels
of hazardous substances above allowable health based levels
occurred.
There is a possibility that there could be releases to the air
during construction activities above acceptable limits for human
health and the environment. Air monitoring during construction
activities in the FWA and brook sediment areas will be conducted
to help assure that no unacceptable levels of air contaminants
are released during the cleanup. Air samples will be taken and
analyzed at an approved laboratory; the U.S. EPA and OEPA will
review the results of this sampling. The levels will be compared
to short-term industry standards to 'ensure protectivehess, as
well as to long-term.calculated levels. If any unacceptable
releases are found, cleanup activities would immtdiately be
adjusted to prevent unacceptable releases of air contaminants.
The companies doing the cleanup work will collect the samples and
monitor the actual operation. Government oversight will be
conducted to help assure that the cleanup is operated safely and
•according to environmental regulations. Performance information
will be made available to the public as soon as it is developed
and verified.
Comment; Once the FWA remedy is completed, will the source of
the contamination to the brook and FWA area be stopped? Why
spend millions of dollars on cleaning up an area if it is going
to be recontaminated in the future. I don't think there is any
real assurance that the sources of contamination will be cleaned
up.
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Response: The Fields Brook Site investigations have found
sources of potential recontamination to the brook sediments and
FWA soils on several of the industrial properties surrounding the
Brook. These areas of contamination are planned to be cleaned up
over the next several years which will help ensure that the
surface waters and FWA soils in the Ashtabula area will not
become recontaminated in the future. Cleanup of these potential
source areas will occur prior to or at the same time as cleanup
of the FWA soils and Brook sediments, so that the Brook would not
be recontaminated after the Brook is cleaned. Sampling will be
conducted in various areas within the Brook and along the FWA
soils after cleanup activities are conducted, in.part to help
assure that the Brook and FWA cleanups remain protective over.
t ime.
Comment: Although the backfill areas and cover areas will be
revegetated over time after the cleanup occurs, befpre that
vegetation is established, there will be a lot of erosion. Heavy
equipment will compact the FWA soils which will change the FWA
drainage patterns. Removing vegetation prior to excavation and
cover activities will also leave no roots and other vegetation to
hold the soil down.
Response ? There is a potential for future erosion of the
excavation and cover areas after cleanup activities occur. Also,
it is expected that there will be some period of time needed
before full revegetation of native plants occurs. Revegetation
sequencing after remedial construction activities occur will
include the initial establishment of grasses soon after
construction activities to help prevent erosion of disturbed
areas. These grasses az expected to ultimately give way to the
establishment and regrowth of native .vegetation after several
years. Operation and maintenance (O&M) activities will also be
regularly conducted and will begin soon after cleanup activities
are conducted. All cover and backfill areas will be regularly
inspected during O&M, and remedial response areas which may be
eroding or not revegetating will be corrected.
Comment: Homes in the residential areas from Columbus west or
State Road west may be contaminated with contamination from
Fields Brook and the FWA. Cleaning up the FWA and the Brook is
thus a waste of money, and these homes should be bought up and
the whole area restricted from future access.
Response? For reasons noted below, U.S. EPA believes it is not
necessary to purchase the approximately 40 residences next to
Fields Brook between 16th Street and Route 11 in Ashtabula, the
several homes next to the Brook near the Ashtabula River, and the
several apartments and townhouses along the north side of Fields
Brook between 16th Street and Route 11. There is no evidence
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that the portions of the backyards of these homes and residences
which lie above the 100-year floodplain area of Fields Brook have
been contaminated by Fields Brook. Further, a spread of
contamination from Fields Brook to these immediate backyard areas
of the homes along Fields Brook is not likely to occur. The FWA
is generally topographically lower (i.e., 10-20 feet lower in
height) than the immediate backyard lawn areas of the homes along
the brook; these immediate backyard areas are significantly
higher than the 100-year FWA and thus it is very unlikely that
any contamination from the FWA area has reached the backyard
areas due to deposition of sedin.ant from rain events.
Comment? There is a lot of money available in Superfund. U.S.
EPA should use the Superfund to clean up the site and not let
special interest get in the way.
•
Response; Superfund enforcement requirements require that, on a
Site-specific basis, the potentially responsible parties (PRPs),
if identified, conduct the work at the Site. The PRPs have
voluntarily conducted extensive studies for the FWA, and have
indicated that they have spent close to $25 million thus far in
investigation and design efforts associated with the FWA, brook,
source areas surrounding the brook and the Ashtabula River.
Although the PRPs have not yet signed agreements and settlement
documents for conducting the cleanup construction activities for
the FWA, brook sediments, and source areas of contamination of
the Fields Brook site, U.S. EPA expects that these settlement
agreements with the PRPs will be signed within the next year.
U.S. EPA and OEPA will oversee the activities of the PRPs.
During a PRP*cleanup, the primary function of U.S. EPA and OEPA
is to ensure PRPs comply with all applicable laws, regulations,
and requirements, and meet all performance standards specified in
the Settlement Agreement.
Comment:; EXECUTIVE SUMMARY, Paragraph 1, last sentence: The
PRPs identified "ECUGs" only for the convenience of U.S. EPA.
The PRPs believed, and continue to believe, that such goals are
inappropriate objectives for risk management. Risk reduction
objectives, rather than simplistic environmental media cleanup
goals, are the most appropriate risk assessment standards for
risk management.
Response; Identification of "ECUGS" does not imply that clean-up
goals are the only objectives of risk management. ECUGS are used
in combination with other risk reduction approaches to manage
risk at a site. U.S. EPA normally develops remediation goals and
remedial action objectives to address both human health and
ecological risks which are identified. This is appropriate and
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necessary as part of cleanup decisionmaking at Superfund sites.
Qomment: Paragraph 2, sentence 4: The PRPs ecological risk
assessment employed appropriately conservative assumption and
applied reasonable input values based on site-specific data.
These assumptions and values were carried through appropriately
in the conclusion of the U.S. EPA Region V baseline ecological
risk assessment. In contrast, U.S. EPA-Edison risk assessment
applies values which are technically inappropriate and which are
not conservative, they are simply wrong. For example, U.S. EPA-
Edison assumed that maximum contaminant levels represented
exposure, that area use factors were universally 1, and that
chemicals were 100% bioavailable. Such assumptions are only
justifiable in a. screening level risk assessment according to
guidance (U.S. EPA 1994), and are not technically sound for more
site-specific and comprehensive risk assessment. More complete
and comprehensive risk assessment under the guidance is to be
based on site-specific data and reasonable assumptions. Such
data and assumptions were employed in the PRPs ecological risk
assessment as reflected in the U.S. EPA Region V baseline risk
assessment.
Response; The authors of the U.S. EPA-Edison risk assessment
applied assumptions which were considered appropriate based on
available data for the site. It was. acknowledged that
assumptions used in Edison's risk assessment were conservative.
As indicated in the report, several reviewers considered the use
of the conservative assumptions appropriate given the
circumstances of available data and site condition.
Comment: INTRODUCTION, Page 1, paragraph 1, first bullet: The
PRPs risk assessment is not included'in this report. The PRPs
document was revised by U.S. EPA, and U.S. *3PA should be
considered the author of the revised risk assessment.
Response; It is acknowledged that the original PRP risk
assessment is not included in the final report; however, it has
been provided to the Administrative Record of the Fields Brook
site in its original and unrevised form. A revised ecological
risk assessment based on the PRP document has been provided by
U.S. EPA, and U.S. EPA did consider itself the author of this
report.
Comment: Page 1, paragraph 1, third bullet: The PRPs did not
"develop" ecological clean-up goals, and does not believe that
such goals are appropriate for risk management. The PRPs
provided ECUGs based on risk assessment findings at the request
and for the convenience of U.S. EPA.
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Response: Refer to the "ECUG" comment response above.
Comment; Page 2, paragraph 4, first sentence: The baseline
ecological risk assessment report submitted by the PRPs in
October 1995 is NOT "provided as Attachment I". Attachment I is
a report prepared by U.S. EPA, incorporating numerous revisions
to an electronic text file provided by the PRPs.
i
Rgaponae: It is acknowledged that the original PRP risk
assessment is not included in the final report; however, it has
been provided to the administrative record in its original and
unrevised form. A revised ecological risk assessment baaed on
the PRP document has been provided by U.S. EPA, and U.S. EPA did
consider itself the author of this report.
Comment:; Page 2, last paragraph, bullets ff to page 4: The
second bullet identifies "probabilistic statistical approach" as
an "unresolved issue". In practice, and according to draft
agency-wide ecological risk assessment guidance (U.S. EPA 1996),
probabilistic exposure estimates are technically sound and most
appropriate.
Response; Current guidance on ecological risk assessment (U.S.
EPA, 1996) acknowledges the potential application of
probabilistic exposure estimate techniques such as Monte Carlo.
Probabilistic exposure assessment may be used to estimate high-
end, individual exposure at a site; this effort is needed to
conduct the risk assessment. If sufficient information about the
variability in lifestyles and other factors is available to
simulate the distribution through the use of appropriate
modeling, e.g., Monte Carlo simulation, the estimate from the
distribution may be used. If only limited information on the
distribution of the exposure or dose factors is available, the
risk assessor should approach estimating the high-end by
identifying the most sensitive parameters and using maximum or
near maximum values for one or a few of these variables, leaving
others at their mean values. In risk assessments where Monte
Carlo analyses have been applied a range of exposure assumptions,
including exposure frequency and duration, are created. The
Monte Carlo approach then develops a distribution from each of
these individual parameters, which may be artificial, then
generates a final risk distribution considering all input
parameters. The value of Monte Carlo simulations in estimating
exposure or risk probability distributions diminishes sharply if
one or more parameter value distributions are poorly defined or
must be assumed. The U.S. EPA ecological risk assessment
guidance also identifies several potential concerns in
application of such models. Use of probabilistic models are not
always "most appropriate" and were not considered appropriate for
this study. U.S. EPA's 4/18/95 letter to the PRPs responded to
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Che PRP.'s proposal to use probabilistic techniques within the FWA
ecological risk assessment; this 4/18/95 letter is provided as an
attachment to the U.S. EPA 10/96 Human Health Risk Assessment for
the FWA.
Comment:; Page 2, last paragraph, fourth bullet: This bullet
identifies use of fish tissue from upstream locations to estimate
"current" risks to mink and heron. In fact, such a use was never
made of these data. The PRPs were committed to remediation of
the brook sediments prior to conducting the ecological risk
assessment. Therefore, species potentially exposed via brook
components of the overall ecosystem in the context of the
floodplain wetland would only be exposed to post remedy
concentrations. The floodplain wetland ecological risk
assessment has no role in determining cleanup criteria for brook
sediments.
Response: Comments on the use of upstream fish tissue are
unclear. If data on upstream fish tissue concentrations were not
used to estimate current risk, than the risk assessment document
failed to fully characterize current risks to on-site receptors
which may consume aquatic organisms. The fish data was used in
part to calculate HQ's. U.S. EPA had previously noted that use
of the upstream areas of Fields Brook (Area 4) as a reference
area for comparisons of HQ values remains questionable, in part
because previous chemical spills may have occurred in this area,
because fish swim up and down the stream and would be in contact
with downstream contamination, and also because calculated HQ
values from the originally selected reference areas at nearby
streams (Red Brook and Whitman's Creek) could have been utilized
for comparisons.
comment: Page 3, first full paragraph, last sentence and
elsewhere: Repeated characterization of the database employed by
U.S. EPA for ecological risk assessment as "questionable" is
unnecessarily vague. Throughout the report, U.S. EPA should
identify clearly and quantitatively the weaknesses believed to
exist in the information base arid state the effect of these
weaknesses on the certainty with which risk assessment
conclusions are drawn. It is important to note that, in contrast
to statements made in U.S. EPA's baseline risk, a large data base
on site-specific chemical concentrations including measurements
in plant tissue, mammals, and invertebrate, has been obtained to
reduce assessment -uncertainty.
Response; Previous comments provided by other reviewers of the
original risk assessment report identified areas of concern
regarding data quality. In its comments to the PRPs ecological
risk assessment, U.S. EPA also identified weaknesses in the data
quality. For example, compositing' across several different
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species in determination of small mammal tissue concentrations
were identified as an issue of potential concern in data
interpretation. Also, U.S. EPA expressed concerns regarding odd
data distributions and truncations which are not justified or
adequately described. U.S. EPA also expressed concerns regarding
interpretations of data presented in such a way as to downplay
the results of tests (earthworm toxicity testa) and presentation
and interpretation of statistical tests (composite biota
samples),
Comment; Page 3, second full paragraph; last two sentences:
Compositing of Phase II samples is not justification for
employing highly uncertain and biased conservative input
assumptions. All Phase III samples were individual organisms
where appropriate, and there are no discernible differences
between these samples and the Phase II composites, indicating
strongly that concern for potential to •obscure* elevated
contaminant concentrations is misplaced. In addition. Phase II
samples were composited (to make analytical mass threshold
requirements) only within species and trophic guilds. All tissue
measurement data employed in the risk assessment are
scientifically sound, and examination of these data indicates
that nothing is "obscured" by their application,
Response; Compositing of tissue samples was identified as one
source of potential uncertainty in the U.S. EPA-Edison risk
assessment. Other sources of potential uncertainty were also
identified within the report including the lack of species
specific toxicity information. U.S. EPA's general practice is to
err en the side of caution regarding use of uncertain data; these
uncertainties are justification for the use of the conservative
input assumptions.
*
Comment; Attachment l. Authorship: This attachment was prepared
by U.S. EPA, not by EA Engineering, Science and Technology. U.S.
EPA modified an electronic text file prepared by consultants to
the PRPs, and is the sole author of this attachment.
Response: Acknowledged.
Comment: Page x, last sentence: It would be helpful to have
citations for this statement, rather than the generalization that
the application is "suggested by some authors" with no
identification of the.scientific sources.
Response; The 'other authors' in question are more accurately
identified as previous reviewers to the risk assessment document,
including U.S. EPA and Ohio EPA.
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Comment; Page 36, sections 5.1.9 and 5.1.10, last sentence of
each: As discussed in comment for Page 3, second full paragraph,
last two sentences above, compositing did not affect data quality
negatively, and in fact allowed application of high mass
analytical methods for Phase II data for comparison with
individual samples analyzed by low mass methods in Phase III.
Because compositing clearly had no negative effect on data
quality, there is no justification on this basis for highly
uncertain and biased input assumptions.
Response; As indicated previously, use of conservative input
assumptions was based on several uncertainty factors, including
the use of composited samples. It is not readily apparent that
"compositing clearly had no negative effect on data quality" as
suggested by the reviewer.
Comment; Attachment 2, Page 2, paragraph 1, second sentence and
elsewhere: Statement that "...very little data on the extent and
magnitude of contamination in the area was available to conduct
this risk assessment..." is repeated elsewhere (for example, on
page 12), and is apparently used to justify the scientifically
untenable assumption that' maximum measured chemical
concentrations appropriately represent ecological exposure. In
fact, hundreds of samples of sediments and biotic tissue have
been taken on the floodplain wetland, and have been reported in
appropriate detail in project reports. This data, rather than
inappropriate assumption of measured maximum, should have been
employed to represent ecological exposure.
Response; The U.S. EPA-Edison risk assessment document was
provided in its entirety as an attachment. Authors of U.S. EPA-
Edison assessment evaluated the data-available at that time and
utilized the data as was considered appropriate. In its comments
to the PRPs ecological risk assessment, U.S. EPA identified
several weaknesses in the data quality.
Comment: Page 13, section 9.0: Cleanup goals based on maximum
site chemical concentrations will clearly lead to over-
remediation, with associated needless habitat destruction and
impact of remedy. Given the large data base on the distribution
of chemicals in the floodplain wetland and the detailed reporting
by location provided in project documents (for example, in the Rl
report), use of maximum concentrations in this calculation is
inappropriate and unnecessary.
Response: Refer to the "ECUG" comment response above.
Commenti Page 14, second full sentence: It is unclear why the
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69
statement was made that 'No site-specific data was [sic]
available for levels of COCs in plants or terrestrial
invertebrates". A number of site-specific measurements of tissue
concentrations in plant tissue and earthworms were made and
reported. This data should have been used to derive site-
specific BSAFs, if needed for the risk assessment, rather than
employing the generic and inappropriate assumption that BSAFs
equal 1.
Response: it is acknowledged that site-specific tissue data did
not appear to be used to estimate contaminant concentrations at
upper trophic levels in the U.S. EPA-Edison risk assessment.
Authors of the original U.S. EPA-Edison assessment considered the
data inappropriate for that application, in part because the data
was not complete enough to make conclusions for the entire
wetland and in part because of concerns raised regarding data
quality.
Comment; The FWA risk assessment follows a previous risk
assessment done for the Fields Brook SOU, where PCB cancer risks
were assessed with a cancer slope factor of 7.7, and PCB non-
cancer risks were assessed with an RfD of 1 x 10"*. At the time
of the SOU risk assessment, IRIS listed a CSF of 7.7, while no
RfD for PCBs was given. The RfD used in the Fields Brook SOU
risk assessment was recommended by U.S. EPA Region V, and was
based on a study of Aroclor 1016 in rhesus monkeys. Many PCB
studies have been completed since the SOU risk assessment, and
IRIS now lists a revised CSF of 2.0 (high end of a recommended
range). There remains no RfD for PCBs, however ATSDR recommends
a minimum risk level (MRL) of 2 x 10~s, based on Aroclor 1254.
The change in the CSF has the effect..of reducing estimated cancer
risks, while the change in the RfD has the effect of increasing
estimated noncancer risks. U.S. EPA does not consider the
revised CSF in calculating cleanup goals, which would have
decreased risks and raised the cleanup goal, but they do consider
the revised RfD, which increases risks. U.S. EPA does this
despite the fact that the new CSF is listed on IRIS, while
significant doubt remains about the RfD. As a result, the FWA
risk assessment contains an unfair bias because U.S. EPA has
failed to accept a valid scientific basis for a change in the
toxicological factor if it leads to a decreased risk.
-Response: This issue relates to how U.S. EPA accounted for the
new cancer slope factor of 2.0 vs. the former cancer slope factor
of 7.7 to derive the cleanup goal for PCBs. As noted in the Risk
Assessment, U.S. EPA calculated two separate cancer risk CUGs for
PCBs, one set of CUGs based on the revised and current CSF and
one set based on the former CSF. The recently revised CSF of 2.0
results in PCB cancer risk CUGs of 1.2 ppm on average in
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.70
residential areas and 9.6 ppm on average in industrial areas.
The former CSF of 7.7 results in PCB cancer risk CUGs of 0.3 ppm
on average in residential areas and 2.5 ppm on average in
industrial areas.
Upon consideration of the various issues associated with PCB
risks at the Fields Brook site, U.S. EPA has made a risk
management decision and has set the total PCB CUGs for the
floodplain/wetlands operable unit as follows: 1 ppm on average in
residential areas, 6 to 8 ppm on average in industrial areas.
These FWA PCB CUGs are slightly lower in concentration than CUGs
based solely on the recently revised CSF, and slightly higher
than CUGs based solely on the former CSF. These FWA PCB CUGs are
based on U.S. EPA'a risk management decision to be protective of
ecological receptors at the site, and to attempt to be protective
and account for the uncertainties regarding the endocrine
disrupter health effects. Also, this decisioiyKeflects U.S.
EPA's attempt to account for the potential syllogistic effects of
the multiple contaminants in the FWA which may increase health
risks associated with the predominant chemical of concern in the
FWA, which is/are PCBs. : ^
Regarding the need to be protective of ecological receptors at
the site in developing the FWA PCB CUGs, the 19$$. FWA Ecological
Risk Assessment indicated the potential for .significant risks to
ecological populations associated with exposure to PCBs. It
should be noted that a FWA remedy which meets the total PCB CUG
of 1 ppm on average in residential areas and 6 to 8 ppm on
average in industrial areas, may still result in chronic hazard
quotients (HQs) which exceed a value of 1 for several species (as
noted in the 10/96 FWA Feasibility Study, Appendix 1) , and that
HQs above 1 may indi< ite a risk.of adverse effects to species.
However, U.S. EPA believes that an FWA remedy which meets the
above noted PCB CUGS woul'd protect the various populations of
ecological receptors which exist or may exist within the
floodplain area for this site. The response actions would reduce
the short- and long-term risks to ecological populations and
reduce these population's potential uptake of contamination via
soil and food to acceptable levels of exposure. It should also
be noted that the HQ calculations were developed using
conservative assumptions which would help provide for
protectiveness to ecological receptors.
Regarding the need to attempt to be protective and account for
the uncertainties regarding the endocrine disrupter health
effects in developing the FWA PCB CUGs, it should be noted that
although the PCB cancer risk slope factor changed based on the
final reassessment report of September 1996 from 7.7 to 2, as
noted within the 1996 Human Health Risk Assessment, at this time
there is no agreed-upon quantitative method within U.S. EPA to
incorporate the endocrine disruption data into a toxicity value.
There is reason to believe that the endocrine disrupter effect
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71
may be the most sensitive health effect of .PCB exposure. Also,
U.S. EPA's general practice is to err on the side of caution
regarding use of uncertain data; the endocrine disruption
uncertainties provide justification for the use of a conservative
PCB cleanup goal calculation.
This decision is also supported by the 12/96 "Public Health
Implications of PCB Exposures" article prepared by the Agency for
Toxic Substances and Disease Registry and U.S. EPA. This study
indicates that exposure to PCBs in the Great Lakes area appears
to cause disrupt reproductive functions, cause neurobehavioral
and developmental deficits occur in newborns which continue
through school age in children,, and result in developmental
problems such as abnormally weak reflexes, greater motor
immaturity and less responsiveness to stimulation.
Also, as indicated in U.S. EPA's 10/22/96 article entitled "PCBs:
Cancer-Dose Response Assessment and Application to Environmental
Mixtures", there are a number of uncertainties associated with
the effects of how environmental processes alter PCB mixtures
after release into the environment, and the resultant
uncertainties associated with assessing risks posed by different
environmental mixtures once released. The report indicates that
among the exposures associated with greatest toxicity and
persistence after release into the environment include ingestion
of contaminated sediment or soil, which is the primary human
exposure route associated with the FWA.
Comment; Pages 4-3 and 5-3: Section 4.3.1 concerning toxicity
values for PCBs states that the cancer slope factor is 2.0.
While this is a true statement, it is misleading because U.S. EPA
used the old cancer slope factor of 7.7 to derive the cleanup
goals.
PCB cancer risks were inappropriately calculated using the former
cancer slope factor of 7.7 (mg/kg-day)*l. It was acknowledged in
the risk assessment that a new range of cancer slope factors has
recently been established for PCBs, but these new values were not
used. No scientific justification was provided to explain why
the former cancer slope factor was chosen instead of the recently
reassessed value.
In the risk assessment report, it is noted that the former cancer
slope factor of 7.7 (mg/kg-day)"1 was based on studies using
Aroclor 1260. The recent PCB reassessment was described as a
"joint consideration of cancer studies and environmental
processes [...] supported by several complimentary sources,"
perhaps implying that the reassessed values are less valid. In
fact, the upper bound slope of 2.2 (mg/kg-day)"1 calculated in
the recent PCB reassessment is based on the same rat study
(Norback and Weltman, 1985) as the former value of 7.7 (mg/kg-
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72
day)'1; the reassessment simply corrected three errors that had
been made in the development of the 7.7 value. Specifically, the
revised value took into account a 1991 reevaluation of the tumor
histopathology data, a new U.S. EPA cross-species scaling factor,
and initial instead of time-weighted doses.
The statement "There is some evidence that mixtures containing
more highly chlorinated biphenyls are more potent inducers of
hepatocellular carcinomas in rats than mixtures containing less
chlorine by weight," (pg. 5-3 of the risk assessment) was an
early hypothesis, but has not been supported by more recent data.
Based on information summarized in U.S. EPA1s 1996 PCB
reassessment report, there is little if any evidence of a
consistent relationship between chlorination levels and cancer
potency. Aroclor 1016 (41% chlorinated) is much less potent than
Aroclor 1242 (42% chlorinated), and analytical methods cannot
reliably distinguish the two mixtures in environmental samples.
Also, Aroclor 1254 (54% chlorinated) is more potent that Aroclor
1260 (60% chlorinated) in female rats in the recent
carcinogenicity study sponsored by General Electric. It is
likely that the cancer potency is far more dependent on the
concentrations of particular congeners. Unfortunately, the
relative importance of each congener is only beginning to be
characterized.
Response; Cancer risks were calculated using both the 7.7 and
2.0 cancer slope factors, and for risk management reasons
(discussed in the previous comment response) U.S. EPA has decided
to use a more conservative PCB CUG than would be calculated based
solely on the recently revised cancer slope factor of 2.0. We
are in agreement with Woodward-Clyde that the new cancer slope
factors reflect considerable effort by individuals in U.S. EPA
and has resulted in an improved interpretation of data on the
ability of PCBs to cause cancer. As-regards to relative toxicity
of variously chlorinated PCB congeners, the? comment is accepted.
It was agreed upon by both U.S. EPA and the PRPs during meetings
in 1994 and 1995 to consider all of the Aroclor's and congeners
together as total PCBs in the risk assessment.
Comment:: Page 4-4: The text (pgs. 4-4 and 6-5) notes that
endocrine disrupter effects "may be best modeled as linear and
non-threshold," and that they "could theoretically be calculated
in a manner similar to the cancer slope factor." We disagree.
Although the precise mechanisms of endocrine disruption are not
well known at the present time, the dose-response relationship
for PCB endocrine disrupter effects is likely to have a
threshold, similar to developmental and systemic effects induced
via other mechanisms. 'Linear, non-threshold models are only
appropriate for compounds that are thought to induce cancer by
directly causing DMA mutations; endocrine disruption is not
believed to involve mutagenesis.
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73
Response: The concept of how best to model toxicity mediated via
endocrine disruption is controversial and the scientific data are
incomplete. It is therefore unclear whether these effects will
ultimately be modeled by assuming a threshold or by assuming a
linear, non-threshold model. There are reasons to believe,
however, that perturbations of a complex system such as the
endocrine system (or the interacting endocrine, immunological and
neurological systems) will be non-threshold and incremental.
Comment: Page 6-4: There are several problems with the
discussion of uncertainty associated with the PCB cancer slope
factor on page 6-4 of the risk assessment. A significant problem
is that only the draft PCB reassessment (January, 1996) is
discussed. Since several changes were made, in the final
reassessment report (September, 1996), this discussion should be
updated to reflect U.S. EPA's final recommendations. For
example, while the draft reassessment recommended a specific
adjustment to the exposure duration to reflect the* persistence of
PCBs in the body, the final reassessment recognized potential
concerns about persistent PCB congeners but did not recommend a
quantitative adjustment. Also, it is incorrectly noted on page
6-4 that "the new document describes PCB cancer potency using two
ranges ..." [emphasis added]. In fact, while the draft
reassessment recommended two ranges, the new, final reassessment
recommended a total of six values - both a central and upper-
bound slope value for three reference points (" high risk," " low
risk," and " lowest risk" ). Lastly, it is incorrectly noted in
the risk assessment report that the draft document included
guidance on the application of a cross-species scaling factor.
While both the draft and final reassessment reports incorporated
a cross-species scaling factor when modeling slope estimates, it
was not recommended that risk assessors apply an additional
cross-species scaling factor when assessing PCB cancer risks.
Response; Comment accepted; since the results and summary of the
risk assessment will not substantially change as a result of this
comment, in part for reasons noted above in the comment responses
to the cancer slope issue, the FWA Human Health.Risk Assessment.
does not require change.
Commenp: Page 6-5: In the risk assessment, it was stated that
"It is likely that the risk calculated from either of the cancer
slope factor underestimates actual risk from the site". We
strongly disagree with this statement. While there are numerous
sources of uncertainty in PCB risk estimates (including endocrine
disrupter effects), numerous conservative assumptions are used so
that.the results represent upper bound risk estimates. For
example, it is noted in the Risk Assessment Guidance for
Superfund (RAGS) (U.S. EPA, 1989) that cancer risk estimates
based on linear cancer models and an upper 95th percentile
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74
confidence limit "will generally be an upper bound
This means that U.S. EPA is reasonably confident that the true
risk will not exceed the risk estimate derived through use of
this model and is likely to be less than that predicted." This
fact is even noted in Table 7 of the U.S. EPA Fields Brook risk
assessment.
Response; The cancer risk is an upper bound estimate of risk and
therefore likely overestimates calculated cancer risk. However,
the statement in question was meant to reflect the entire scope
of PCB toxicity including endocrine disruption effects. In
addition, the statement was intended to represent the limitations
in the risk assessment due to an inability to calculate a risk
for these more subtle endpoints.
comment; Table 7: He have several concerns with the discussion
of general uncertainty factors in Table 7. It is misleading to
represent many of these uncertainty factors as "over- or
underestimating risks," implying that each possibility is equally
likely, when in fact, they are far more likely to overestimate
risks. By definition, toxicity factors (slope factors and
reference doses) are designed to err on the side of
overestimating risks. For example, even though it is
theoretically possible that humans could be more sensitive to
PCBs than animals, an uncertainty factor is incorporated into
toxicity values to specifically account for this possibility.
Furthermore, despite large numbers of PCB-exposed workers, PCBs
have not been causally associated with cancer in humans based on
epidemiology data. Another example is linear extrapolation from
high doses to low doses. This approach will only underestimate
risks if the dose-response relationship is superlinear (which has
never to our knowledge been suggested for PCB carcinogenicity) .
Response; U.S. EPA partially agrees with this con.rnent. Safety
factors are intended to overestimate risk and should be stated as
such. High dose to low dose extrapolations tend to overestimate
risk and should be noted as such. U.S. EPA disagrees about the
animal to human extrapolation. There is a great deal of
uncertainty in such an extrapolation and that uncertainty may
over- or underestimate risk.
comment; Page 3-5: The U.S. EPA risk assessment is overly-
critical of the exposure survey conducted by the PRPs, and states
that "...the survey did not focus upon those individuals who
reside along Fields Brook and thus does not accurately represent
the population whose exposure to the brook is most of concern."
This is not the case. The survey area is bounded by portions of
East 14th Street, Columbus, East 15th Street, Route 11, East 23rd
Street, and East 21st Street. Of the 100 households that were
surveyed within this area, 40 of them are on property directly
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75
adjoining Fields Brook. The other 60 households, while not
adjoining Fields Brook itself, include those across the street
from the brook, and within this small defined area. U.S. EPA's
assertion, that the survey did not focus on households likely to
be exposed to the brook, is false.
Response: U.S. EPA does not believe it was overly critical of
the PRPs survey; the several significant concerns regarding the
survey are summarized in the FWA Human Health Risk Assessment.
In addition to concerns noted in the Risk Assessment, U.S. EPA is
concerned that the PRP's survey inappropriately disregarded
hunting and fishing as a frequent activity along Fields Brook.
During 1993 and 1994 discussions with the PRPs, U.S. EPA
expressed concern that this conclusion did not consider that
these other streams are not in close proximity to their residence
(i.e., in their backyards), and disregarded the circumstantial
evidence of frequent use discussed above (e.g., hiking,
campfires, play) . Further, the survey did not address the issue
of children's exposure.
Comment; Page 6-3: The text incorrectly states that "The [PRPs]
proposed that the size of the FWA exposure units be larger than
those used in this risk assessment; that is, they proposed that a
smaller number of exposure units be demarcated within the FWA for
evaluation." This statement is false. The PRPs initially
proposed that the FWA exposure units correspond to the SOU
exposure units, and U.S. EPA accepted this proposal.
Response; The PRPs raised concerns regarding the length and
total area of the FWA exposure units being considered by U.S. EPA
in its 9/19/94 comments to U.S. EPA, including whether separate
FWA exposure units existed on both s.ides of Fields Brook. U.S.
EPA's 10/20/94 letter to the PRPs noted that it was appropriate
to divide the FWA into the same ten exposure units that were
previously used for Fields Brook sediment. U.S. EPA also noted
that because separate populations exist on each side of Fields
Brook, separate exposure units must be considered on each side of
the ten exposure units. The PRPs continued to disagree with U.S.
EPA's designation of separate FWA exposure units on each side of
Fields Brook into early 1995.
Comment; Page 4-5: Section 4.3.8 concerning arsenic toxicity
cites a cancer slope factor of 1.75. This value is out-of-date.
The correct value of 1.5 is given in Table 5. It is unclear which
value was used in the risk calculations.
Response; As shown in Appendix D, the calculation spreadsheets,
the updated value of 1.5 was used in the risk calculations. The
value of 1.75 given in section 4.3.8 was inadvertently in error.
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76
Comment : Table 3: This table contains typographical errors; it
is not clear to what extent, if any, these errors affect the risk
calculations. The errors include:
qomment; PEU2 . maximum concentration of PCE should be 2500
Response ; Acknowledged. As the exposure point concentration is
the lower of the maximum and the 95% UCL the risk calculations
are not affected.
comment • PEO2 . maximum concentration of 1,1,2,2-
Tetrachloroethane should be 580 pg/kg
Response ; Acknowledged. As the exposure point concentration is
the lower of the maximum and the 95% UCL the risk calculations
are -not affected.
Comment ? PETM . basis for exposure point concentration for
PCBs should be listed as 95% UCL
Response t Acknowledged. The 95% UCL value was used in the risk
calculation.
Comment •. FEua . maximum concentration of hexachlorobenzene
should be 480,000
Response • Acknowledged. As the exposure point concentration is
the lower of the maximum and the 95% UCL the risk calculations
are not affected.
Comment ; FEUB . 95% UCL on mean and exposure point
concentration for hexachlprobutadiene should be 1900 /tg/kg.
Response • Acknowledged. This revision lowers the calculated
hexachlorobutadiene carcinogenic risk of 3.6 E-08 to 8.66 E-09,
and the hazard index from 0.0046 to 0.001. The revision does not
change the overall FEUS carcinogenic risk of 1.1E-04, and hazard
index of 1.4.
Comment:; Page 3 bottom through page 4 top: This text states
that the CUGs were developed for the FWA by considering only the
soil ingestion exposure route; that dermal exposure was not
considered in developing CUGs. This statement is false. Both
the PRPs and the U.S. EPA risk assessments considered both soil
ingestion and dermal exposure, and both were used in U.S. EPA's
development of the CUGs. .
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77
Response: Comment accepted. The CUG and risk calculations were
properly conducted and considered both soil ingestion and dermal
exposure, and thus no change to the risk assessment text is
required.
Cgmment; page 5 top: This section appears to state that CUGs
were developed for the FWA in 1993. However, the risk assessment
was not done until 1995 (PRPs risk assessment) and 1996 (U.S. EPA
risk assessment), and this 1996 U.S. EPA risk assessment is the
first document that contains CUGs.
Rgaponae; U.S. EPA submitted a list of FWA CUGs to the PRPs on
10/20/94, and this list is provided as an attachment to the 1996
EPA Human Health Risk Assessment. These 10/94 CUGs are the
current CUGS for the FWA.
V. f*' tinman»• fca. fcBA VHDL BAn* it of
the Fields Brook site. Regarding use of the terms FEU's vs. EU's
within this report, unless otherwise*noted within the report,
both of these terms refer to the floodplain area exposure units
under discussion.
Comment; Page 1-1: The text notes that U.S. EPA has divided the
site into four areas of concern, three of which are considered
"operable units" associated with the Fields Brook Superfund Site.
The text incorrectly describes the operable units. The 1986 SOW
originally described two operable units, the Sediment Operable
Unit (SOU) and the Source Control Operable Unit (SCOU). The
Floodplain and Wetland Area (FWA) has never been officially
designated or referred to as an operable unit by the PRPs. The
PRPs voluntarily proceeded with FWA sampling, risk assessments
and feasibility study alternatives beginning in 1994.
Response: U.S. EPA considers the FWA a separate operable unit of
the Fields Brook site, and no separate formal designation is
required by U.S. EPA in order to refer to the FWA as such.
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78
Comment ; Figure 1 does not accurately depict the SOU and FWA
investigation areas. The. Source Control Operable Unit is not
shown.
Response ; The figure provides the reader with the general areas
involved in the SOU, FWA and Source Control investigations.
Howe vex, due in part to photocopying losses in clarity, the
reader may have difficulty in deciphering and segregating these
different areas.
.*
comment ; Page 2-3: Section 2.1.2 discusses SCOU activities and
indicates-that all field work was completed in the Farll of 1995.
The text doeff not reference the completion of a Feasibility Study
(FS) that identified remedial alternatives that were developed
for the remaining source control areas that represented potential
recontaminatlon sources to Fields Brook.
Reaponact Comment accepted; since this paragraph is intended to
provide the reader with an overview of progress at another
operable unit, the text does not require change.
Paxje 2-4: Section 2.1.4 refers to the
Floodplain/Wetlands Area Operable Unit. This reference is
incorrect .
Rgaponae : U.S. EPA considers the FWA a separate operable unit of
the Fields Brook site.
•
Comment : Page 3-2: The text describes groupings of r£Us for
residential and industrial land use areas. There appears to be
some confusion regarding actual designation of FEUs (floodplain
exposure units) and Eus (sediment exposure units). The listing
provided describes exposure units (Eus) for the sediment operable
unit and incorrectly describes the residential and industrial
Eus. The designation break for residential and industrial FEUs
in the FWA was Route 11 and in the SOU was State Road. In the
SOU, residential Eus included: Reach 1, 2-1, 2-2, 3, 4, 11 -l,
11-2, 5-1, and 5-2. and in industrial Eus included 11-3, 1-4, 6,
7-1, 8-1, 8-3, 8A, 13-1, 13-2, and 13A.
Response • The above statement is correct regarding designations
of reaches of Fields Brook into FWA vs. brook sediment exposure
units. However, regarding use of the terms FEU's vs. EU's in
this report, unless otherwise noted within the report, both of
these terms refer to the floodplain area exposure units under
discussion, and the reaches identified on pages 3-2 and 3-3 of
the FWA RI report correctly designate which reaches of the FWA
are considered residential vs. industrial use.
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79
Comment: Page 3-2: It should be noted that the FWA project only
considered response areas in residential areas (FEU 2 and 3) and
industrial areas (FEU4, 6, and 8).
Response; This report is an RI report which discusses the nature
and extent of contamination and history of the site; response
area discussions are provided within the FWA FS report.
Comment; Page 3, section 3.3, Figures: The figures provided in
the RI (Figure 3 through 7) that identify Phase I, II, and III
Floodplain Sample Locations depict the proposed locations as
shown in the Work Plan. They do not show actual surveyed
locations and minor sample numbering modifications that occurred
during field sampling. Figures showing final sampling locations
that were surveyed to exact locations were provided in the .
October 1996 Feasibility Study.
Response; Comment accepted; since these figures are intended to
provide the reader with a general overview of sampling locations,
the report does not require change.
Comment; Page 3-4: In the second full paragraph, the text
indicates that all samples were analyzed for the 130 chemicals.
This is not correct. The 137 samples collected during Phase III
were only analyzed for the 11 COCs identified for the FWA
(1,1,2,2 tetrachloroethane, tetrachloroethene, trichloroethene,
vinyl chloride, benzo(a)pyrene, hexachloroethane,
hexachlorobenzene, hexachlorobutadiene, arsenic, beryllium, and
PCBs).
Response; Comment accepted; since the results and summary of the
data summary writevps do not substantially change as a result of
this comment, the report does not require change.
Comment; Table 2: The source of the summary analytical data
tables included in this appendix was not referenced. The PRPs
provided U.S. EPA with electronic files. It is assumed that data
provided in these summary tables is consistent with the PRPs
database.
Response; This comment makes a correct assumption; the report
does not require change.
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-------
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5
•
2
10
g
f.
i
Flgur»7
FlMtptakiEipnwfllMlM
MMMf lal RnpwiN AIMS Mltniilhn VII
FtoodpWn-WMUnd Am Proposml RwrndW Rnponn AIM
-------
•
MMMtflll RwpWMt AraM AltMMUw VN
noodMHn ttMmd Ana PropoMd RwmdW RnponM AIM
-------
FIELDS BROOK
PROPOSED ON-SITE CONSOLIDATION AREA
CROSS-SECTIONAL VIEW
d
o
Vegettlhre Cover
••—=^-
6-incb Top Soil Layer
24-iaeh Soil Layer
l/4-inci Oeoaet
40-nil Liner
IMnch Sand/Gravel Layer
On-site Consolidation Area
Soii/Sediacnt/Debri
6-iach Sand/Gravel Layer with
Syttca
In-iltu Soils with Recomputed 6-inch Top Lay<
-------
Tabl* 1-1:
Su&mary of Soil* Data for P1U 2
Summary of Phase I. EL aad IB Data For
Fields Brook TWA Surfact Soft
Flood Flaia Expoiurt Unit 2
~~ «•!!••» Arok»«nc Suad*rJ
ttr
(%) (•«*•)
1.U
lJ>Ti
1.2-Dichl
U
-------
Table 1-1: Summary of Soil* Data for PBU 2 (continued)
Flood Plaia Eipoanrt Uort 2
Pirn-* ••••••^p A**ifceitTr ^'••"'••^ x*^.
Dcviattoa UCLM
(•8*8) <»f*I> ("8*8)
C£BVI ^SCflUBB
*»•••/* a**""^^^
rltlOliVttJBBBV
FIUOKBC
Hamchlor
••••nevBeBBH^
Heaachlar eponde
*«Ma*«e^MeBw« ^^^•^^•»
IJ^^^jEJaJjMB^MJMMMMI
Hexachiorabaadkac
I^wi
aMUBHHfft »e^** ^^^fWJ "^^™
bfahoncfalor
K»««lj*iBiW/^>""^^
Mohyieae Chloride
WMhfhatne
V*M|ffBMMMMHew
Phrn ir* *****"*
BtteMMtl
« DDJU8)
DlJMHM
«y»*HB
Scyrtne
Teoachloroethene
Tolucae
ToalPCBs
TncolofOctDCBe
Vinyl Chloride
Xytenea(toal)
alpha^BC
Vp^B^OiUmitHt
bm-BHC
bun-EthvlhcxyOphthilae
WU^A Sl««»7M^"^/«^M""^^^^^
dela-BHC
MmB*Afic (LiadtBe)
•(•jAHHM^^avCft^v \*weiB^^^^^^/
^"^"^^^
AftttHMMNF
ABHaVBII/
- . _M
te••ni••«
yiBBfll
r«Lri»»
Cobalt
rr^mmm
^^T*l^»
Cyaaide
Ina
Lad
5
38
7
3
7
33
26
8
24
3
21
27
37
1
38
11
24
32
38
18
1
22
3
3
19
37 .
13
14
12
39
1
23
39
26
•w
28
39
39
J 9
39
39
13
39
39
39
39
39
39
39
39
39
39
39
39
38
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
39
17
39
39
12.82
97.44
17.93
7.69
17.93
84.62
66.67
20J1
61J4
7.69
53 .26
69J23
94.87
2J6
97.44
28.21
61.34
82.05
97.44
46.13
2J6
36.41
7.69
7.69
48.72
94.87
33.33
33.90
30.77
. 100
2.56
64.10
100
66.67
71.79
100
100
100
100
76.47
100
100
0.0030
1.2
0.076
1J
0.015
97
6JO
OJO
0.76
0.079
7.1
0.74
1.1
0.031
u.
0.062
13 .
0.21
360
6.8
0.0030
0.62
0.061
0.0059
4.4
16
18
0.47
0.13
23800
U
40
16300
1.8
11
59300
517
36
103
0.58
63600
147
0.031
OJ2
0.24
0.16
0.14
14
0.81
0.25
OJO
OJ7
OJO
0.14
OJ3
0.28
0.30
0.0070
-0.077
0.027
24
0.19
0.032
0.021
0.060
0.037
OJ7
1.3
0.13
0.090
0.13
14362
5.4
15
3877
0.67
3.8
16368
104
17
30
OJ3
37608
66
V.ld
0.25
0.17
0.33
0.65
22
1.2
0.16
0.14
1.9
1.1
0.15
OJ4
0.15
0.26
0.010
0.40
0.051
60
1.1
0.15
0.10
0.19
0.19
0.95
17
0.45
0.20
0.55
3965
1.6
10
5179
.0.47
3.3
14764
111
6.6
20
0.14
8198
26
0.50
0.43
1.7
0.19
303
1.4
0.29
0.30
0.98
0.044
0.28
042
0.31
0.48
0.012
0.053
0.088
284
0.068
0.015
0.015
0.14
0.097
0.53
4.0
0.53
056
0.42
15928
6.7
19
19215
1.4
84
2435'
150
19
m»
57
040
3969S
"5
suinoujcu
-------
T«bl« 1-1: Sun«*ry of Soil* Oat* for PSU 2 (continued)
Flood Plain Eiposure Unit 2
PwMctcr
MafDcmm
MUflBBC
Mercury
Niekd
Pootanm
CflMitHII
Silver
Sodium
ThillittiB
VmdniB
KSEcF
Detect*
39
39
39
39
39
I
22
24
6
39
39
Saapk* 1
39
39
39
39
39
39
39
39 «,
39wt
3^^
3^f
Detected
(H)
100
100
100
100
100
20.51
56.41
6U4
15JS
100
100
Deact MCM
16200
2630
11
157
3170
9.6
13
1350
1J
902
297
3106
S6I
3.2
67
1S46
4.3
3J
320
3J
149
112
Oevuuioa
1337
530
3.3
36
550
3.3
3.4
254
2.7
119
66
55%
UCLM
5610
1004
17
82
2029
12
S.3
398
8.5
226
206
93MMO
-------
Table- 1-2:
iry of Soil* Data for PSU 3
Suotaiary of Phase L n and m Data For
Fields Brook FWA Surface Sofls
Eloodplaia Exposure Unit 3
1,1,1-Tnchiorocame
1.1^2-Tcneatawt
1.2.4-Ti
U-Dfcateot
U-Dichlnmithmi (tool)
1.3-
1.
2
4.4-.0DT
4-MettoyH
A«doM241
Artdor-1154
Carton Duulfidt
Iadcao(i.2J<.d)pjncae
Mafeylcae Chloride
Stymie
2
10
2
9
1
11
3
2
23
4
1
2
1
21
1
31
1
2
5
22
27
9
6
3
1
4
15
13
It
1
7
32
1
24
14
4
11
33
3
23
30
10
41
41
41
41
41
41
41
41
41
41
6
41
41
41
41
41
41
41
41
41
41
41
41
41
41
41
41
41
.41
41
41
41
41
41
41
41
41
41
41
'41
41
41
4.H
24.39
4.SS
21.93
2.44
26.1:
7.32
4.IS
56.10
9.76
16.67
4.U
2.44
61.29
2.44
75.61
2.44
4.SS
12.20
53.66
65.15
21.95
14.63
732
2.44
9.76
36.59
31.71
43.90
2.44
17.07
71.05
2.44
31.54
}4.15
976
26.13
15.37
7.32
56 10
73.17
24.39
O.I
0.22
0.0060
O.tt
0.19
0.041
4.2
O.IT
0.066
0.010
0.010
0.0020
0.0050
2J
0.0060
530
0.041
0.0080
0.17
OJ3
0.67
0.14
0.041
0.037
0.0030
0.10
0.023
0.24
0.071
0.0040
0.011
OJO
0.0030
99
47
2.0
0.16
0.37
0.055
0.24
0.23
00030
0.0076
0.013
0.0069
0.41
0.40
0.0094
0.49
0.41
O.OOtO
0.31
0.025
0.0075
0.40
0.12
0.40
29
12
0.0061
OJ9
0.32
OJ7
OJ6
0.37
0.0012
0.0077
0.0092
0.0072
OJ6
0.32
0.40
0.0070
OJO
0.40
6.4
2.1
0.43
0.35
0.06
OJ9
OJ1
0.29
0.0055
0.0047
0.034
0.0014
1.1
1.1
0.0079
U
1.1
0.010
1.1
0.034
0.0047
1.1
0.40
1.1
92
6J
0.0016
1.1
1.1
1.1
1.1
1.1
0.0066
0.0046
0.014
0.0056
1.1
LI
1.1
0.0051
1.1
1.1
11
94
1.1
1.1
0.079
1.1
1.1
1.1
0.0026
0.0012
0.013
0.0077
0.43
0.35
0.011
0.45
0.37
0.0017
.0.40
4.1
0.0011
0.43
0.11
0.42
539
6.2
0.0014
OJ6
.0.32
OJI
0.34
0.43
0.0090
0.0012
0.0093
00013
0.43
OJ4
0.44
0.011
0.36
0.46
14
1.9
0.40
0.34
0.094
0.43
0.34
0.29
00011
•JUNO
-------
Tabl. 1-2
Summary of Soil. D«t« for
FloodpUiH Exposure Unit 3
FBU 3 (continued)
P«r— -r
Totaat
ToolPCBs
TricUarocmaK
Xyteno(wol)
baa-SRC
bn(2*cinyu>ejtyijpnUiintt
A ttCHMaMMM
Anak
Barim
Bayllnm
Cadanm
CalcflBB
ChfOOBBB
COM*
Cflffpfff
• "FF ™ '
CynadB
Ira
Lad
MigncBom
ManpMH
Mcmiy
Nickel
Site
SodhnB
ThiUimB
Vaaadraa
Ziac
NoBfca
Dcttctt
21
35
31
20
32
3
i 31
41
25
41
32
11
41
41
41
41
5
41
41
41
41
40
41
- •
41
11
35
1
41
39
Saapki Detected Dtact
(%) («^kl)
41
40
41
41
41
6
41
41
41
41
41
41
41
41
41
41
6
41
41
41
41
41
41
j •
41
41
41
41
41
41
61.29
17.50
75.61
41.71
71.05
50.00
75.61
100.00
60J!
100.00
71.05
26.13
100.00
100.00
100.00
100.00
13.33
100.00
100.00
100.00
100.00
97.56
100.00
IfVl 4WI
100.00
26.13
15.37
2.44
100.00
95.12
0.64
0.047
530
0.19
0.050
0.24
9.6
24200
24
21500
1.7
9.7
23500
470
40
79
OJ2
50400
97
1620
951
9.2
147
?A4A
3040
12
414
0.62
•42
621
Mtaa
0.052
0.0047
29
0.021
0.006
0.045
0.60
15231
13
1234
0*£T
L7
49O
61
14
27 -
0.11
31091
44
3977
54C
LI
42
1 ^Uf9
17W7
12
200
4.7
92
135
Stamdwtf
Dcvusio*
0.12
0.0079
92
0.047
0.00139
0.10
1.6
3751
JM
*J433
OJ3
2.4
5311
90
4.6
14
0.015
5439
19
10W
195
1.1
31
**m
5tl
2.7
11
1.9
154
105
99%
UCLM
(•|/kt)
0.092
0.0060
473
0.043
0.0010
9.3
1.2
16392
16
1155
0.95
2.3
7677
71
14
31
OJ3
32450
49
4259
630
2.1
41
f A^£
1976
2.1
222
1.7
106
152
9M000
SUinOILXLI
-------
Table 1-3:
•of floila Data for PXU 4
of Phase I. IL aad m Dau For
Fiddi Brook FWA Surfact Soft
Flood Plain Exposure Unit 4
(*)
ScaaAird 95%
UCLM
(
•1241
Aiodor-1254
AndoM260
19
6
2
17
1
22
13
6
23
1
17
1
1
3
10
20
17
34
3
1
1
26
24
31
17
7
10
2S
17
1
3
6
3
1
33
7
29
36
36
36
36
36
36
36
36
36
36
J6
36
7
36
36
36
36
36
36
36
36
36
36
36
36
36
36
35
35
36
36
36
36
36
36
36
36
36
36
36
36
36
33
17
6
47
3
61
36
17
64
3
47
3
14
I
2t
56
47
94
t
3
3
72
67
16
47
25
17
14
14
3
If
28
71
47
3
14
17
14
3
92
19
tl
a
0.0040
an
3J
0.04
9.1
3.0
0.36
2.4
0.0020
0.045
0.0)1
04111
0.21
0.033
2.7
0.11
560
0.27
OJJ
0.041
OJ1
OJ7
1.6
0.22
OJS
0.094
0.014
0.01
0.0010
0.032
2.1
OJ3
1.1
0.031
0.013
0.090
0.23
0.0010
1.1
0.061
230
0.67
0.11
0.16
0.96
1.0
0.40
O.tt
0.99
0.24
0.11
0.19
1.0
0.041
LO
0.95
OJO
0.90
63
4J
4J
0.16
OJO
0.93
0.63
0.94
OJt
0.91
1.0
0.19
0.1S
0.11
OJS
0.90
1.0
1.0
0.91
0.91
OJ9
0.11
0.69
0.96
29
2.5
0.36
0.34
2.0
2J
U
1.9
2J
0.53
OJ6
2J
2J
0.094
2J
2J
0.61
2J
133
9J
92
OJ4
2J
2J
1.4
2J
2J
2J
13
0.36
OJ6
OJ6
OJ4
2J
2J
U
2J
2J
2J
0.36
1.9
2J
46
i.S
0.52
0.32
1.7
1.1
0.72
1.0
1-2
0.54
0.41
2.4
1.1
1.0
l.l
4.1
0.74
2.1
3161
35
45
0.26
1.2
1.1
0.91
1.2
1."
1.1
2.0
0.51
0.44
OJ1
0.55
1.1
2.0
1.1
2.4
22
U
0.44
0.75
2.2
365
-------
Tabl* 1-3
Summary of Soil* Data for PKU 4 (continued)
Flood Plain Exposure Unit 4
ParaaMttr
HBM^hlMMMkMM
Io4coo(1.2J<.d)pjr!BM
Metbykne Chloride
NiphitiitfiM
PheaiDtfaitDC
PynM
StyicBt
ToncDi
ToalPCBs
TM»|>|MM*|I«M
Xyiena(tool)
fc'ifl TTflB».lti H_. flak Ik mt
A htflPJtflMMBi
Ancoic
Bantu
n__.lf :,._
BetyiUBB
^2j4fliffim
flaiaim
CufOBUB
Cobalt
CotHHT
*•**•*•'•• ,
Cyiaide
Ine
Lad
Magncsaa
Maapaot
Mocuy
Nicnd
PoooiBB
SekBBB
Sihcr
Sodna
TfaallioB
Vaaadtaa
Ziac
910000
su&noiLjcu
*»aT
27
7
17
27
14
32
30
I
23
34
22
36
36
16
36
20
24
33
36
36
36
3
33
36
33
36
32
36
32
2
16
V
2
36
31
NBBfecr
SiBptal
36 .
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
33
36
36
36
7
33
36
33
36
33
36
33
36
36
33
36
36
36
HI
Dfttctttf Dcact Man Dcvtaiioa
(*)
73
19
U
47
73
39
89
83
22
72
f m
64
94
72
f A
61
100
100
44
100
56
67
100
100
100
100
43
100
100
100
100
97
100
97
6
44
82
6
100
86
pa«r>
(•8*8)
190
5.9
0.26
2.2
0.031
0.72
1.1
0.10
38
OJ2
560
8.6
3.9
15
43400
38
11000
6.4
20.60
40600
620
69
290
1J
62300
161
7420
2720
19
199
3220
2.7
9.4
•95
0.98
949
621
(•8*8)
9.2
095
V.*rf
0.94
0.23
0.92
0.60
0.67
0.13
0.072
63
046
W*^^V
0.18
1.6
18565'
13
2452
0.9*
. 3-*
'l3554
123
18
51
0.29
38882
60
4070
825
3.9
65
1864
6J
2.6
376
6J
192
158
32
2J
OJ3
2J
1.8
1.9
OJO
-------
T«bl« 1-4
(MO
M'-DDE
4.4--ODT
Aredor-1242
AiodaM24S
Aredor-1234
ry of Soil* Data for F»U 6
•oury of AIM L n, aad XU Data For
Fiddt Brook FWA Sarface Soft
Flood Flaio Exposure Uait €
23
12
9
24
15
27
16
15
12
22
1
2
I
2
S
30
13
1
33
1
17
29
36
IS
1
7
27
U
6
7
14
14
2
1
1
7
34
40
40
40
40
40
40
40
40
40
40
40
14
14
40
40
40
40
40
40
40
40
40
40
40
40
40
36
40
40
40
40
40
40
40
40
40
40
14
14
14
40
40
31
30
23
60
31
6S
40
31
30
55
3
14
7
5
20
75
33
3
S3
3
43
73
90
45
'•3
IS
S
s
3
15
15
6S
33
15
IS
35
35
14
7
7
IS
15
4,"
•^
0.13
O.S4
4J
OJ2
110
0.73
OJ2
S.7
0.61
0.015
0.47
0.0050
0.13
0.037
Lf
0.34
22
610
0.27
LS
L4
12
1.1
0.032
0.62
0.051
0.045
0.19
11
OJ5
3J
OJ3
OJ9
0.10
0.67
1.7
0.43
0.19
0.034
0.015
1.S
W»^w
0.13
0.13
L3
LI
4.1
0.94
LO
0.40
. LO
Ll'
. OJ6
OJI
1.1
Ll
0.26
Ll
6.7
74
6.6
U
OJ4
Ll
1.1
Ll
Ll
0.765
0.14
0.13
OJI
0.14
Ll
Ll
Ll
1.1
LO
1.0
. 0.60
OJI
OJ7
0.14
0.95
U
0.30
0.27
19
19
IS
IS
19
1.4
19
IS
1.4
L3
1S5
2.16
OJO
19
11
131
11
19
IS
IS
19
IS
19
1.4
OJ3
OJ2
1J
OJ3
19
19
19
19
IS
IS
L3
L3
1J
OJ3
IS
^__
-------
T*bl« 1-4: Suana
ry of Soil* Data for FRU 6 (continued)
Flood Plate Exposure Uoit 6
Suadard 99%
Men Deviation UCLM
Hqnchta
laden* U4-c4)pynne
MttbykaeOikrid*
Te
Tfl
ToolPCBl
Vinyl Chlorioi
aipaa-HHC
alpna-ChlocdBM
Iron
Moony
e
1
39
32
13
IS
29
15
32
27
12
34
23
34
31
2
23
1
1
5
30
1
1
1
40
23
40
33
31
40
40
31
40
10
40
40
40
40
39
40
14
40
40
40
40
40
40
40
40
40
40
40
40
40
40
40
14
14
14
40
14
14
14
40
40
40
40
40
40
40
40
40
14
40
40
40
40
40
40
40
40
u
7
9t
10
31
43
73
31
80
a
30
13
63
13
71
3
31
7
7
36
73
7
7
7
100
31
100
S3
71
100
100
93
100
71
100
100
100
100
91
100
90
13
0.42
1.0
320
170
4.3
0.47
0.45
0-23
3J
4J
0.13
S9
0.10
610
36
t_3
0.44
0.19
0.01S
4.5
11
0.072
0.25
0.027
26300
33
9620
6.0
12.10
121000
29
116
0.77
130000
231
1330
3070
22
3100
3.4
L.1
0.41
33
11
1.2
1.1
0.12
1.0
LO
1.0
0.12
7.0
0.11
76
4.4
OJ5
0.09
030
0.29
0.65
2J
OJO
OJO
OJS
14465
13
2053
1.1
4.0
26193
147
14
41
0.22
36593
56
3556
947
4.2
74
1315
4.1
2.9
0.74
72
31
2.9
2.9
0.26
19
2.1
2.9
•OJ1
It
OJO
131
11
1.4
0.26
0.69
0.69
1J
3.6
0.69
0.69
0.76
5105
1.0
2422
L3
3.4
30621
213
5.6
25
OJ3
19619
39
1163
661
4J
•4
756
3.1
1.3
230
220
46
1.8
1.3
0.22
2.3
1.4
1.4
0.34
641
0.23
1633
172
0.45
0.16
48
31
204
7.1
36
48
101
16452
15
4416
2.1
7.8
59331
221
16
57
0.31
40425
67
3943
1224
16
90
1773
13
suinoa_xxj
-------
Table 1-4: Summary of Soil* Data for PSU 6 (continued)
Flood Plaia Exporarc Unit <
Afftianic Suadard99%
Mna Dtviuioe UCLM
(H) (mtflrt (e^kt) (a^kt)
12m 24 40 60 13 13 It TT
Sodhnn 21 40 70 1410 342 244 423
Thallium 5 40 13 5.6 4.2 16 1.7
Vanadium 40 40 100 1710 237 354 390
Zinc 40 40 100 339 146 65 16S
-------
T«bl. 1.5, sugary of Sell. D«t« for Flu 8
Sammuj «f Phase I. O, and fflDtu For
FUdj Brook FWA Surface Sofe
Flood FUia Eipoturt Unit •
' (tool)
Andor-1242
AractoM24S
AradoM254
Anckr-1240
21
32
31
15
11
1
21
17
7
3
7
4
31
15
3
20
1
16
29
9
37
20
35
22
13
42
42
42
42
42
42
42
42
42
42
42
24
24
42
42
42
42
42
42
42
42
42
42
42
42
42
42
42
42
42
39
42
42
42
42
42
42
42
42
42
42
42
42
42
42
42
42
42
40
5
7
2
43
29
43
19
40
34
74
4.
4
2
2
40
41
a
52
2
74
10
12
67
74
90
3*
24
2
50
44
17
7
17
10
74
34
7
41
2
42
49
21
a
4t
S3
52
31
12
0.034
0.0030
0.0020
1J
0.19
47
0.52
OJ3
9.0
0.74
OJ4
0.0047
0.007
0.022
0.092
0.041
7.2
OJ1
0.44
270
3.4
9.4
0.15
0.79
L4
OJS
OJ4
0.00030
0.054
0.17
OJ2
0.01
0.91
1-2
M>
OJl
0.037
0.10
0.00030
0.44
1.9
0.12
2.1
0.17
17
14
0.44
0.095
0.094
0.094
OJO
0.44
1J
0.41
0.43
OJT
OJ7
0.71
047
OJ1
1J
0.41
OJS
OJ2
0.40
5.7
30
3.1
4.0
0.47
0.44
OJS
0.45
0.41
0.094
OJt
0.44
0.015
0.094
0.10
OJ1
0.47
0.44
030
0.40
0.094
0.43
0.54
0.052
0.49
0.41
30
1.2
0.41
cstuda
Dcriati
"T3T
V.4*
2.2
OJS
0.2t
OJS
1.0
0.99
7.2
0.99
1.0
1.4
1.0
11
11
0.9S
14
1.0
1.0
1J
1.0
16
53
14
16
1.0
1.0
0.32
0.99
0.99
OJS
1.0
1.0
0.26
OJS
OJ9
OJ2
1.0
0.99
0.9S
1.0
OJS
1.0
1.0
0.19
OJ5
1.0
95
IS
0.99
N 9SH
M UCLM
- <•«*«)
^^O.U7J
0.47
0.04S
0.076
0.046
0.72
OJ5
O.SO
1.1
0.43
0.14
0.41
4.2
3.4
0.42
1.4
0.75
0.4S
OJ3
0.4S
20
399
17
25
0.53
OJ4
0.52
0.4S
0.56
0.077
0.59
OJ6
0.042
0.071
0.07S
O.OS9
OJ4
0.45
OJS
0.44
0.077
0.45
0.90
0.049
0.44
0.49
132
1.9
0.69
-------
Table 1-5: Summary o£ Soils Data for PEU 8 (continued)
Flood Plain Exposorc Unit I
(%) (i
AritfeiMtic Suadtrd 99%
MOB Deviuioa UCLM
(•»%•) (•**!)
IS
6
29
36
31
23
25
33
26
If
7
31
1
41
1
21
42
32
25
42
42
42
42
21
42
42
42
42
41
42
40
16
27
19
12
42
39
42
42
42
42
42
42
42
42
42
42
24
42
42
41
42
42
42
42
42
42
42
42
42
24
42
42
42
42
42
42
42
42
42
42
42
42
42
43
14
69
16
90
55
60
79
62
41
29
74
2
100
2
67
100
76
60
100
100
100
100
ss
100
100
100
100
91
100
95
31
«4
45
29
100
93
0.74
0.12
0.056
4.6
1.9
12
0.17
270
11
OJO
2.4
67
0.00040
31500
21
43
1370
19
9.7
74100
1510
29
147
0.66
51400
263
5470
12900
5S
90
..I
17
79S
16
420
0.43
0.057
0.41
OJ4
0.63
0.47
0.49
0.033
34
0.7S
0.036
OJ1
5.7
0.094
17053
5.1
15
297
1J
Vi
15225
266
14
49
OJ3
36702
62
3513
1411
13
44
1796
3.S
3.1
274
3J
430
194
u.yy
0.15
0.99
1.0
0.17
0.52
l.S
0.09
51
14
0.10
Li
11
OJ1
4933
3.2
11
279
3.0
2.0
15261
345
4.9
30
0.13
10364
39
947
2000
15
17
742
3.9
4J
167
34
514
95
u.jg
0.060
0.61
0.44
0.92
0.64
0.46
0.056
231
1.6
0.044
14
14
0.074
11616
7.1
19
375
2.2
2.5
22216
466
16
39
0.29
40274
71
3139
1797
121
51
2127
1.4
7.1
342
7.1
764
235
fsonoo
SUBfSOIUXU
-------
-*-•— —.a *•• _aa
P«r
Bi«k
Specific
Chemical
Aricwc(i)
Beryllium
beuBHC
lamiMBHC(UwtaM)
bit(2-Elhymuyl)phtlMble
Carbaiole
Chloroform
4.4'DDB
4.4 DOT
1 4-PichlorabcntfM
I.l-Dkhkvocihcac
Hf fi tf hlifrotof ft t ITT
Mr i erhJflrfjthi i ailif fif
HciachloroewaM
Mcihylcae chloride
PCBi
PAH • BcaicXaVuMhrMCM
PAH • teuofryiovraMheM
PAH • B«ucXa)pynM
PAH-ChryiaM
PAH - Dihe*i(a,h)aMhrafieM
PAH • l*deMcd)pynae
1.1.2.2-TctrachlaractfaaM
TeuachtoroctheM
1.1.2-TrtchloraedMM
TrichloroelhfM
Vinyl chloride
U.S.BPA
CirciaofM
Oau
A
B2
C
C
B2
B2
B2
B2
B2
B2
C
B2
, C
C
B2
B2
B2
B2
B2
B2
B2
B2
C
B2
C
B2
A
Slope
Factor
(miA*day)
1.75
4.3
1.1
1.3
0014
0.02
0.0061
0.34
0.34
0.024
0.6
1.6
0071
0.014
0.0075
7.7
0.73
0.73
7.3
0.0073
7.3
* 0.73
0.2
0.051
0.057
0.011
1.9
Source t
M
IMS
IBIS
IBIS
HEASTd
IBIS
HEASTd
IBIS
IBIS
IBIS
IIBASTd
IBIS
IBIS
IBIS
IBIS
IBIS
IRJSb
c
C
c
,* •
c
C '
IBIS
BCAO«
IBJS
BCAO.
HEASTd
Oral
MMorptkM A
PndkM
0.95
0.01
0.5
O.S
0.25
0.
091
0.95
0.5
0.5
0.5
0,5
0.5
0.5
0.7
1
0.11
0.91
1
Dermal Cance
tbMfptMM
PnctkM
0.001
0.001
0.10
010
0.25
0.25
0.05
0.10
0.10
0.25
0.05
0.25
0.25
0.25
0.05
006
0.03
0.03
0.03
0.03
0.03
0.03
005
0.03
0.05
0.005
0.05
rUakUvtJof
18-06
n
o
•»*•
p
o
>A
u)
•
P
fWAMCM*
-------
ASSUMniONS:
Wm*%mm A_ _ 3492 •
5o*Ho itia*dfc«t«c«f>clOf (•§*»?) 0.20 "
AvcuilMTUaetocm) TO g-
S-
•. Soutco of Toikiiy Valuci: J*
IRIS - IttcfnMd Riak blonMik» Syttm. U.S. EPA »T
(BCAO) • U.S. EPA
HBAST-HMkltEA«uA«MSMMMStMMMfyTaMM.U.S.BPA n
bUwkr review by BPAwoitcnMip JJ
cS^fS2^jJ5^^
d.
•. VcrilUd by
-------
Table 2-2: PWA CUOs: a*»id«nti»l Mon-Carcinogen
ftcMt Bi^ook
Ckancp Goal Coaerc-u tbotn fc r Nooekmnofcc la Floo MM.'
fiaaed On In;-saoa *--*> Dera»J Abwrpdo* By A RoUcntfaU Reccpur
SoO
CkMioicM
Aceoapbmeoe
Acctoae
Aatfanoeae
Anenk
oo6 mis
01 mis
03 mis
00003 mis
C.07 DCS
O005 DOS
0.0003 DOS
002 . mis
06 mis
02 mis
OOOI DUSf
01 mis
002 mis
001 ins
1 DOS
OOOS mg
O037 HEAST d
O02 OUS f
00005 DOS
AiflAA ECAO
1MHM Pfc«^H^
009 mis
O09 DWHA
Ol HEAST
AAflO niT K
lUWy IKAa* V
002 mis
04 ms
10 HEAST k
Ol DUSfc
10003 CUB j
O04 DOS
004 DOS
oooot mis
0002 mis
oooi mis
ou mis i
O0003 HEAST c
A AC IDTC
ILUD IWa>
O005 HEAST
O04 HEAST b
002 OUS e
O03 DOS
0.005 OUS b
0.005 mis
0.01 nus
0.00008 HEAST
VYCVB)
Onl
kbsorpaoe /
i tacooo
1
1
OJ
095
O06
O01
05
025
1
O9
O05
1
1
1
OOS
Ol
06 '
072
0-5
0.9
O95
O9
1
0.5
1
08
1
I
0.03
015
AM
U.7O
i
i
0.03
06
0.95
OJ
!
I
S
Dennal
hblOfJXMQ
Fiacuuo
0.03
O05
OJ)3
OOOI
OOOI
OOOI
O10
025
0.05
O25
OOOI
OOS
O05
0.05
OOOI
OOOI
OOOI
OOOI
010
on*
VJU^
OJS
025
0.05
AM
V.IJ^
0.05
025
025
O2S
010
003
003
025
025
025
0.001
0001
A/X
IMD
025
025
0.001
0.03
0.001
0.001
0.03
0.001
Healm Hazard-
pedficCoacemnaoo
for Hazard Quot»eo<
Set Equal n 1
Imtfltf}
6JE*04
9.7E*O4
3.0E«05
5.9E-MJZ
8.6E*04
5.0E«03
2-OE*02
5.4E403
5JE«05
9.6E-*04
1^E*03
9.7E*04
1.9E«04
9.7E-f03
1.2E+06
6JE-»03
4.7E4O4
2.6E-»04
3JE«02
43£*O3
^^KTW
4.4E«04
4.4E404
9.7E-»O4
• oc^Al
O*oC^VJ
UE«04
3 JE+03
4^E«06
4.8E-KM
2JE*02
4.0E-MM
4JE+04
3.7E*02
9.9E-KQ
4.9E*02
1.6E*05
3.8E*02
5ttg./\^
.5C*U*
r5E*03
2.0E->04
2.3E+04
3.IE«O4
6JE-03
6.4E*03
!.!£->»
I.OE-D2
-------
Table 2-2: FWX CUG«: Residential Non-Carcinogen (continued)
lOel
Specific Coooencnooo
for Hmd Quoarai
StfEqultol
Lf£«03
t.9E<*06
3.IE-»05
4 fat) x SO
A fat) x 50
2 ttM eoMevd per dqr far 70 yein
-------
Per
Oil
Hntary at 69 Paya par Yaar fcr li Ya»ti)
Chemical
US EPA
fCiMf
Ctau
Slept
Oral
tel
Abaoqxk*
CancarRiakLivdor
18-06
(HM/k|l U»
AncMc(|)
Beryllium
•CUBIC
famnaBHC(UadaM)
bit<2-Eihyliaiyt)piMtialaM
Carfcatola
Chloroforai
4.4' DDE
4.4' DOT
H-DicMorotaMCM
1 . 1 -PicMoroctfum
lleMchlarobcMicM
HaiacMoraattfaditM
HeaacMaracAaM
McthylcM CMorraa
PCB«
PAII • Bauotafcathfacaa*
PAH • BcaaoXbXtoavaatliaiia
PAH » BaMOtalpyNM
PAH-dvyaaM
PAH • Dil«Bata»aaaVacaM
PAH • hdMtQ.TJ n
-------
M«M» BfMfc • MMtfpMiM Mrf WctlMidl
CteMM^ C«y CMMfirtnllMM F«r CmrliwfCM In FloWflahM wM Wetlands Sol
I On iHjuU** And Piinul ANtgHlM By An Oec^tf^M
(EifMwv rrt^MKjr «T M l>«y* pw YMT f«r IS YCMS)
EXPOStmi ASSUMPTIONS:
CMWlNM
CUM it linn it teyrtto* n» (**H»)) 0
CMMeipuNnfNMMyWqrt^r) 0
OMnpoimdiraitaiffMn) 0
CkJM Mtfao XI MPOMd (CBll%yMll 0
Adui«MMkoflV»titN(t|i) • 33
9 AdulHU* ».*.»« lugtuhm ran (««/fcy) 0
0
0
_- »•••••»••«•• ywy_y^^-»- w^ • ^ _•*** l^ ^miP^ »••••••* ^T^T»«M _ W
M
u
3f»nii»a^ ii»»ijmw»j 70
^ .
i« •. SOWCMOC Tmldijr VHMK
M IMS-lMCfraMdlUHManMitaiSyMMi.UJ.ePA
ewrkoMMMd CMMto Md AMMMJM Offlw (BCAO). U J. EPA
• HEAST-HeridiBlfcctiA SIIMIBJ T«Mti.UJ.BfA
p . k. Uadcr icvltw ky EPA wotkgia^p
u c. RdMtvc punacy VMM died to picKnhwy draft docMWN • ftovWoMl OOTHMB rar QMMtMlvf RMi AmnnMl of
^J^^^^ltt A^^^iAtfiA ft&M^^^A^L^^A Itfl *»^A ^^AA ^••..^a. ^ •» i^ -A A -J » fefl^M^ IflA^
IWJlfUK flnMWIC IffVPCWOML U.9. BrA UIIM Ol IfCMR Ml BBVMIMMMI lUHMMMIt PMin^ ITTJ.
d.tradgitvi»wkyCHAVB»uitpu» .._._..
•. VWwlM vy WOra|RMip^ MIS IMM pMdMf tMlfM OfCVMtMOl •KMOII.
I. RfBBM (IpOMd fSiV • IMJMi| • 90 pCfCHDH MffWR OTM Of MMIIV '• OIHI 30 • 19400).
f
-------
Table 2-4: FWA CUG«: Industrial Non-Carcinogen
•ar for 25 Yean)
Heal* Hazard-
Specific Coocemnooo
ft* Kauri Quoacat
SaEqaalioI
0.09
0.0* DWHA
0.1 WAST
0.009
002
•*.
10 WAST*
0.1 OUS»
04)003 IMS a
•ftaUium
04)02
0001
014 OUSi
0.0003 HEASTc
0.06
0005
0.04
0.02
0.03 OUS
0005 OUS h
0.005 UUS
0.01 UUS
000008 HEAST
1
1
OJ
095
O i
001
OJ
0129
I .
O9
005
T
1
1
005
01 ,
04
07}
OJ
0.9
O95
O9
I
OJ
1
OJ
1
1
O03
O15
09S
1
1
0.03
0.6
0.95
OJ
1
1
003
040
003
0001
O001
04)01
O10
025
O05
O2S
- 0.001
O05
OLOS
O05
04)01
04)01
04)01
04)01
O10
003
025
O25
040
0105
OOS
O25
025
029
OIO
040
003
029
029
O29
O001
0001
005
029
029
04)01
0.03
0.001
0.001
0.03
0.001
3JE+04
4JE+06
L2E*05
7.9E+03
7.1E«05
1.4E«05
7.IE«04
79E>06
4.1E+04
3.1E«05
I.7E«OS
2.4E403
3.1E«04
3.9E«09
3.9E«05
7.IE*05
6.4E+O4
1.4E405
3JE*06
4.2eVM77
4.1E«C5
2J&05
3.1E«05
3.1E*03
I.6E«03
4JE403
UE«06
2.5E*03
1.7E*O5
1JE«05
2.IE*OS
76E~04
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Table 2-4: TWA CUG«: Industrial Non-Carcinogen (continued)
ef « D«yi per Ytar for 25 Y«n)
CM
Dow (RID) Soeret Abrnpooe Abmpoao
(a)
Specific Coocomaoa
far Hand Qaaoeet
SciEqailtol
(ortt)
0.2 OUS I 0.05 1.46406
0.01 OUS 0.15 0.25 4.0E404
0.09 UUSt 1 O.OS 6.4E405
0.004 OUS 0.11 0.05 17E«04
0.006 ECAO 0.91 04)05 5.0E-MX
0.007 HEAST OJ 0.001
2 OUS I OM
0.3 OUS 03 0.001 2JE<»06
TiUH.U3.E?A
ECAO.Aprtl9»2
per dqr far 70 yon.
ft* let I
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Tablet 3: FWA Buaaa R«alth and Ecological COC«
Fie!* Brack FWA
Ckraucal
Arsenic
Barium
Dduo^ajpyrene
Beryllium
Cadmium
Chromium
IMmw^fh Ij MV ttMH MMM
Hexachlorobutadiene
Hexachloroethane
Lend
Mercury
Potychbrinattd Btphcnyls
119? T««rBchlrwrw>rluiw>
Vanadium
Vinyl Chloride
HnmttHeaitB
X
X
X
X'
X
X
X
Ecotofkal
X
X
X
X
X-
X
X
X
x
-------
Tafclo 4-1: Loc«tlon-«p«ciftc ARARs (continued)
ReqirireaMcf
IS. Reqiiires that TSCA lai^Us meet jpfciried siting, design,
haadltaf, nd monitoring nqiwomms [40 CFR 761.60 and
761.75 (B)|.
STATE STATUTES AND RICULATtOfO
I. Facilitits where uuuinm. storage, or disposal of hazardous
warn will bt conducted is prohibited within the 100-year
floodpbm. (OAC. Title 3745. Chapter 54. Section IS)
2. NewRCHA
t4 MVJlJtfl^B^iJ*l
time. (OAC TUt 3745,
or disposal of hazardous waste
of a tett displaced in Holocene
54. ScetioB ||)
or baft liquid hazardot
. saB bed fonMOoeB, underground mines, or
(OAC TMe 3745. Cheater 54. Section 11|
IQKC 37144» tin (61 fdil
2.
-------
Tatol* 4-lt Location-•pejcifie AJLUU
Raqtinsirat
RcqnmiMl
LocatiaaHSnedllg Ljws/Reoeiirnnnta
FEDERAL REGULATIONS
I. Limits activities in floodptoin. Ftoodptaia is defined as tne
* --- ^ _ftJ -- A ^^_^A ^••'•^a — la j aM^^ ^^^^^^_ ^fc^S^fci^fc^^^ ^^ft^^K^
luwianu no niauvciy nat arena wnjumaf Tfwtff
waten including flood prooe areaa of offchora islands.
inf hading at • naiimn, dm area) wfe^cci to a w
fronr cfcnei of flooding in my gmn yor." Fcdml
mu*t cv«laaMttitpocauial«fhciiof woontilMi in* *
^^.^k^^^^Mfl^hA^ ^^K^ ^^^^h^J ^^^W^^^^K^ B^^^^^^^l^^ d^^^^i^ ^^^^K^^J£^ft ^fci^^fc*»»J*fc^^fc
iiuuu|Miiii MM •vou vovvnv tnipw nw raRMOiu •cnviiia
[40 CFR « J02 aad Appwfa A)
National Hinoric Pmemtign Act fNHPAl
8. Requires the pmervanon of historic propenies included * :
eiifiM* for the National Rcfistcr of Historic Places and to
minimia ham to National Historic Landmarks. [16 LSC *~
3 JSB-; 40 CFR tf.30l(bX 36 CFR Pan 63. Pvt 65. Part 300
WtMtmmAct
9. Linitt activitia wttka ama dangnad as wilderness areas jr
National Wtldlift Raftg* Systtm. [16 USC I3tl.
16 USC Ml; 50 CFR 53. 50 CFR 27]
Wild A Scaiifc Rivtrs Aa
10.
rivan that an drtgiatad a» wild, scenic, or
[16 USC 1X71; 40 CFR 6J02(e)]
2. MifiunUatt tovcfM mpKts on i
[40 CFR 6.302(a) an
A|
i dangnatad at wetlands.
ClfSfl Ait Act CCAA>
Non Attainmcm Area
Cle«i W«» Acs SoettM 404
II. Require tne use of reasonably
110 avoid, to the extent possible, (RACD for sources located in
ia destruction or loss of wetlands. [CAA Tidt L Subpan 2|
[40 CFR 230-JJ1; 33 CFR 320-3301
Requires Federal
ro! technology
it veu
4. Pronibits
aarge of drida^ or Wladaanrial into
the US. w.tbout a permit. (40 CFR 230. 33 CFR 320-3301
3. Section 10 permit i
•fleeting navigable'
i or work in or
, (33 IOC 403. 33 CFR 320-3301
Ac:
preserves their habitat
i for mitigation of inpaca. fUUSC 1331 etseec
SO CFR 200. 50 CFR 402)
Fidi ;
I Wildlife Ci
7. Requires coordination with federal and stale agencies on
activities aflecttng/modirying streams or rivers if the activity
ha* a negative imped on fish or wildlife. (16 USC 66"! fl sag.:
40 CFR 6 302(f)J
12.
Any activity modUyint * •<•• or river, which ».u have i
dimsiffn. chaaneKaej. or ftttr action and which affects fish
wildlife nat be insplanMaiad win action to protect t'tsh or
wildlife tl6US.C«6l«tsnq.l
sndRl
Act (RCRA1
13. A tiretmem/storage/disposal (ISO) facility wuhm J '• 00-.ear
ftoodplasn natst be liesigMd. constracted. operated and
mantHned to avoid <
14 Landfills may not be located within vulnerable
areas. fRCRA 1004
-------
Tablet 4-2: Action-specific AltAft*
EDERAL REGULATIONS
Substances Control Act (TSCA)
Establishes regulations to govern the stooge and disposal
of PCBs including PCB-cemamnaud soil. (40CFR 761)
National Pollutant Discharge Eliminauoa System
9. Requires dischargers of pollutants from any point source
into surface waters of the United States to meet certain
requirements and obtain a NPDES pennji
[40 CFR 122.431
The PCS Spill Cleanup Policy. Subpan G of §40 CFR 76 1 . applies to
spills that occurred after May 4. 1987, the effective date of the policy.
SubpanG is not an ARAR at the Fields Brook Site, since PCS
contamination occurred before the effective date of die policy. SubpartG
is instead identified as "to be considered'' (TBC) guidance.
4.
s.
Specifles requirements for disposal of materials contaariag
PCBs. [40 CFR 761.601
Dredged materials dm contain 30 pom of POki or
tmttt 0*Y QUDO900 Of lA BK IBCID0IHOI' Of CDBttttG
landfill, aa specified in the regulation*:. (40 CFR
76l.60(aX5)l
for TSCA landfills. (40 CFR 761.751
National AnMettt Ait Qualify Standards (NAAQS)
6. gtttbtittiTT f^ifm air quality standards to protect public
health and welfare.
[40 CFR 50)
Ambient Air Moutonnf
7. Specifies methods
[40 CFR 53J
Prohibits)
of the U.S.
330J
Hft CFR 230.33 CFR 520-
Ambient Water Quality Criteria
10. Requires EPA to publish water quality criteria for specific
pollutants for the protection of human health and the
protection of aquatic lite. [40 CFR 131]
II. Establishes general anil specific standards for pollutants
that are discharged to a POTW. (40 CFR 403]
Storm Wi
12.
for industries is
water to waters of a* United
WSKT discharge from
ri analysis requirements
which discharge storm
Includes storm
[40 CFR I22|
RCRA Corrective ActiM
13. Provides far
Unit Rite
of a Corrective Action
ttqoiremeras for
i. [40
Disposal
Provides rrgnlartons tor ike entiftrnimi of haardous
(40 CFR 260 et al|. Specific
40CFR30Q.440fC722/93tt
PB
-------
T«bl« 4-2: Actioa-ftpacific AHAR. (continued)
IS. Specifies requ
for
of hazardous waste
management unto. (40 CPU 264. U7(c).22a
-------
Trntol* 4-2: Action-«p«cifie ARAJU (continued)
Ohio Air md Wner Pollution , •
I Requires that i peniiii MI install fPTH ot plttis tnuu
tBA-n »d shall
ibte ambiciit
JBUBBHBa
Ohio
401 Remlatkm
1. Specifies subsuntive atari* for Section 401
criteria for dradfjof. nni«f.ob«niainf. or
of the SUM. (OAC 3745-32-061
tot On aotiflabo* of
of
-
Specific
s.
a.
(Al
IB2L
22.
23.
24.
29.
26.
i>7'.T«*ir£*3:5>i'
?l«. ftfrtC
I
27. RMUJM th«
EPA (OAC3745.54.53fA>«d
-------
T»hl« 4-2: Action-«p«cific ARARs (continued)
Rcqitrramt
*****
wuhin the Aih*****!!! Rivtr Ruin
>OAC 3743.I-.I4I
iftnCS ^tftSSf tttfi ofiUCfi^il^yRft FOf 9iP6^^^B__S^^Kln6^^*A
CA^M^AMA «k^ -*• •-•- *—
speants nw tuovviw opMty
from «aboB«y wnfrn. (OAC 3745*I74T(A
IOA.C
tor coomrf «f ftii.i
o.
fQAC
method* of nili
(SAk
tCU
Soceiflo the
to inMll fQAC 374S.?7^t«> fO|
4. Addinotul «iini rtouifemtiii. w
••~irr inuniin Mimin iiniiiiiiiii niiiiinii
uteice inai. f
5-17^7mi rP> rr.. ,14,i
3. Coniimaion
3745.27^(0 (D.WI
6. Fitiil cloturc of ]
(B) (G)l
7. P"*MUhed when
(Pi IB (M) rmi
10.
II.
16.
17.
it:
AC 3743-27-11 f At
jqAfc 3745.27-M1
fluidjrdi
-------
T«bl« 4-3: Actioa-«p«ei£ie AJUAa (eonciau«<4)
igygggfg
•h i CM
5.
t.
miUbb
oCpoUuum from any
Must men
tuedardi 'either
r *bc«
*V determined
2.
(OAC. TWt 3745.Chapter 331
tePOTWi.
[OAC TUB 1745. <
73.
-------
4-3: Aceioa-«p«cific
(coatiau«4)
of PQUMMB from «ny
of fti UMH* SUHB. Must mat
«t suadvds 'either
•or '
•). determined
(OAC Tfcte 374S.Oupt«r 33|
OAC THi IMS.
TS.
-------
Table 4-2: Action-«p«ci£ic ARAB, (continued)
Rcqvirramt
fQAC 3745-54-331 46. Reoutita that antica bt nveato total land luthonuea
the CWCIN Of
31.
32.
rmenencv. fOAC 3745-54-561
g_--^«i-« —;-
374S.SS.t4l
fQAC 374J
Reauim th* nooc. h. •*
fflTrniniitirflimml.itfh
47. Contiincn hoidtiM It
K* rruininnMi
(OAC 374S-SS-74I
4S. H
4 in cm>ti|gf imtflt noc reset wiih
t& Itf^iv IM^IMM»| frtA/* T7^^ ^C T^l
fOAC 374S-5546/A. B. C. Rl
51
59
45.
-------
jat«xaativ«
£ rafefftan Crtort*
Overall Protection
of Health and Environment
Compliance with ARARs
Long-term Effectiveness
. and Permanence
Reduction of Tojocuy. Mobility.
or Volume through Treatment
Short-term Effectiveness
lmnleineni*feli • • •
1 • • •
O 1 • »
• • • •
• • • •
5.8 19 a 21.3 69
State Agency Acceptance
Community Acceptance
• Fully meets criteria 1
^aflitnumfv ifeeot^nfG oi tH0 t*t ofnifiA
the public comment period
Paroally meets cntena 3 Does not
meet cntena NA Not applicable
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