United States Office of
Environmental Protection Emergency and
Agency . Remedial Response
EPA/ROD/R03-92/159
September 1992
SEPA Superfund
Record of Decision:
Abex Corporation, VA
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50272-101
(REPORT DOCUMENTATION
PAGE
1. REPORT NO.
EPA/ROD/R03-92/159
3. Recipient's Accession No.
4. Title and Subtitle
SUPERFUND RECORD OF DECISION
Abex, VA
First Remedial Action - Subsequent to follow
S. Report Date
09/29/92
7. Authors)
8. Pertorming Organization Rept. Ho.
». Performing Organization Name and Address
Project/Task/Work Unit Na
11. Contmct(C) or GrarnXG) No.
(C)
(G)
12. Sponsoring Organization Nam and Address
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report & Period Covered
800/000
15. Supplementary Note*
PB93-963917
16. Abstract (UmH: 200 words)
The Abex site is a former brass and bronze foundry in Portsmouth, Virginia. Land use
in the surrounding area is mixed residential, commercial, and light industrial. The
site is located approximately one-half, mile west of Elizabeth River, within the
500-year floodplain for the South branch of the River. The Elizabeth River Basin is
heavily industrialized and receives wastewater discharges from U.S. Naval facilities,
heavy industry, treatment facilities, urban runoff, and boating and docking facilities.
From 1928 to 1978, Abex operated a facility that melted used railroad car journal
bearings into sand molds to cast new railroad car bearings. The sand casts became
laden with metals such as lead, antimony, copper, tin, and zinc. The foundry
operations also produced stack emissions of fine particulate matter. During Abex's
operations, waste sand was disposed of in a 1-acre area immediately north of the
foundry. In 1984, Holland Investment and Manufacturing Corporation purchased the
portion of the Abex site that contains the former foundry, which included five
buildings and is referred to as the Holland Property. In 1986, EPA discovered high
levels of lead in the foundry waste within the Abex Lot and in the soil of many
(See Attached Page)
17. Document Analysis a. Descriptors
Record of Decision - Abex, VA
First Remedial Action - Subsequent to follow
Contaminated Medium: soil
Key Contaminants: organics (PAHs, PCBs), metals (chromium,
b. Identifiers/Open-Ended Terms
lead)
c. COSATI Reid/Group
Availability Statement
. Security Class (This Report)
None
20. Security Class (This Page)
None
21. No. of Pages
68
22. Price
(See ANS1-ZM.18)
See Instructions on Raverae
OPTIONAL FORM 272 (4-77)
(Formerly NT1S-35)
Department of Commerce
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EPA/ROD/R03-92/159
Abex, VA
First Remedial Action - Subsequent to follow
Abstract (Continued)
neighboring residential lots. That same year, Abex performed a removal action to
excavate and remove lead-contaminated soil from residential areas around the Abex lot,
and to pave and fence the Abex and McCready Lots. In 1992, Abex excavated and removed
additional contaminated soil from adjacent properties. This ROD addresses contamination
in soil and waste materials on the Holland Property, Abex Lot, and McCready Lot and in
the surrounding properties within a 700-foot radius of the foundry facility, as OU1.
Future RODs will further investigate ground water, ecological impacts, and additional
remediation of the soil for OU2. The primary contaminant of concern affecting the soil
is lead, although other site contaminants include organics including PAHs and PCBs and
chromium, a metal.
The selected remedial action for this site includes demolishing all foundry operations
buildings, with removal and decontamination of associated equipment and demolition debris
at an offsite landfill; temporarily relocating residents during soil excavation; removing
and disposing of offsite any asphalt and concrete from paved areas prior to soil removal;
excavating surface soil with lead concentrations greater than 500 mg/kg and subsurface
soil with concentrations of lead exceeding 1,000 mg/kg from non-residential areas, from
around foundations, and under residences in affected residential areas; temporarily
storing these onsite prior to treatment; testing, then treating any soil that exhibits
TCLP toxicity onsite using stabilization; retesting the treated materials to ensure they
meet RCRA LDR requirements, followed by transporting and disposing of treated and
untreated soil and waste materials offsite at a RCRA landfill; disposing of water
generated during the treatment processes offsite at a POTW; backfilling all excavated
areas with clean fill; installing erosion and sediment control measures; and monitoring
air for dust and lead during remedial activities. The estimated present worth cost for
this remedial action is $28,891,243. There are no O&M costs associated with this
remedial action.
PERFORMANCE STANDARDS OR GOALS:
Chemical-specific soil excavation goals in residential areas down to the water table,
which are based on EPA's policies for soil clean-up levels per OSWER Directive
#9355.4-02, include lead 500 mg/kg for surface soil to one foot below surface and
1,000 mg/kg for subsurface soil from one foot below surface to the water table. All
excavated soil and waste material will be tested using the TCLP method and, if they
exhibit toxicity, they will be stabilized onsite to meet RCRA LDR standards prior to
offsite disposal.
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RECORD OF DECISION
ABEX CORPORATION SUPERFUND SITE
PORTSMOUTH, VIRGINIA
PREPARED BY
THE U.S. ENVIRONMENTAL PROTECTION AGENCY
AND
THE VIRGINIA DEPARTMENT OF WASTE
MANAGEMENT
SEPTEMBER 1992
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TABLE OF CONTENTS
PART I - DECLARATION
I. Site Name and Location 1
II. Statement of Basis and Purpose 1
III. Assessment of the Site 1
IV. Description of the Selected Remedy 1
V. Statutory Determinations 4
PART ZZ - DECISION SUMMARY
I. Site Name, Location, and Description 5
II. Site History and Enforcement Activities 8
III. Highlights of Community Participation 10
IV. Scope and Role of Response Action 11
V. Summary of Site Characteristics 12
VI. Summary of Site Risks 15
VII. Description of Alternatives 34
VIII. Summary of Comparative Analysis of Alternatives . 42
IX. Selected Remedy and Performance Standards 53
X. Statutory Determinations 58
XI. Documentation of Significant Changes 62
PART ZZZ -RESPONSIVENESS SUMMARY
I. Health Effects of Lead Contamination 64
II. Communication with Impacted Residents 80
III. Compensation for Impacted Residents 84
IV. Proposed Cleanup Activities 87
V. Future Site Investigation and Remedial Action....100
VT. Enforcement-Related Issues 101
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LIST OF TABLES
Table 1 - Extent of Soil Contamination at the Abex Site.... 17
Table 2 - Activity Patterns for Exposed Residents 20
Table 3 - Exposure Factors 23
Table 4 - Cancer Potency Factors 24
Table 5 - Reference Doses 26
Table 6 - Standard Assumptions for UBK Hodel 27
Table 7 - Baseline Risks for the Abex Site 32
Table 8 - Remedial Alternatives 35
Table 9 - Comparison of Alternatives 52
Table 10 - Estimated Costs of Selected Remedy 57
LIST OF FIGURES
Figure 1 - Site Location Map 6
Figure 2 - Map of Site Features 7
Figure 3 - Site Zoning Map 21
APPENDICES
Appendix A - Administrative Record Index
Appendix B - Glossary of Superfund Terms
ii
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RECORD OF DECISION
ABEX CORPORATION SITE
DECLARATION
I. SITE NAME AND LOCATION
Abex Corporation Site
Portsmouth/ Virginia
Operable Unit One
II. STATEMENT OF BASIS AND PURPOSE
This Record of Decision (ROD) presents the final remedial
action selected for Operable Unit One of the Abex Corporation
Site (Site), located in Portsmouth, Virginia. This remedial
action was chosen in accordance with the Comprehensive
Environmental Response, Compensation, and Liability Act of 1980
(CERCLA), 42 U.S.C. §§ 9601 et seq., as amended by the Superfund
Amendments and Reauthorization Act of 1986 (SARA), and the
National Oil and Hazardous Substances Pollution Contingency Plan
(NCP), 40 C.F.R. Part 300. This decision document explains the
factual and legal basis for selecting the remedial action and is
based on the Administrative Record for this Site. An index of
documents for the Administrative Record is included in Appendix
A.
The Commonwealth of Virginia concurs on the selected remedy.
III. ASSESSMENT OF THE SITE
Pursuant to duly delegated authority, I hereby determine,
pursuant to Section 106 of CERCLA, 42 U.S.C. § 9606, that actual
or threatened releases of hazardous substances from this Site, as
discussed in Section VI (Summary of Site Risks) of this ROD, if
not addressed by implementing the remedial action selected in
this ROD, may present an imminent and substantial endangerment to
public health, welfare, or the environment.
IV. DESCRIPTION OF THE ?ELE.CTED REMEDY
The EPA, in consultation with the Virginia Department of
Waste Management (VDWM), has selected the following remedial
action for the Abex Corporation Site. This ROD addresses the
first of two operable units for the Site. This operable unit
(OU1) addresses contaminated soil and waste material present
within approximately a 700-foot radius of the Abex foundry
facility (See Figure 2). The former foundry buildings will also
be addressed as part of OU1. The second operable unit (OU2) will
further investigate ground water, offsite ecological impacts, and
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the need for additional remediation of soil beyond the 700-foot
radius. The selected remedial action for OU1 addresses the
principal threat at the Site by excavating and treating the
highly contaminated soils and waste material and by demolishing
the buildings associated with the former foundry operation.
Treated material, soil containing low levels of contamination
that do not require treatment, and building debris will be
disposed of offsite in an approved Resource Conservation and
Recovery Act (RCRA) landfill.
Response actions began at this site in 1986 when EPA
identified high lead concentrations in the Abex foundry waste
within the Abex Lot and in soil of neighboring residential lots.
Pursuant to a Consent Order signed with EPA in August of 1986,
Abex excavated and removed contaminated soil at varying depths
(generally 6 to 12 inches) from residential areas around the Abex
Lot, primarily in portions of the Washington Park Housing
Project, the Effingham Playground, and around the Seventh Street
Homes.
Additional high lead concentrations in soil of residential
areas were identified in the Remedial Investigation and
Feasibility Study (RI/FS) for OU1 completed in February of 1992.
Pursuant to a Unilateral Order issued by EPA in March of 1992,
Abex excavated and removed additional contaminated soil to a
depth of approximately twelve inches in portions of the
Washington Park Housing Project and the Effingham Playground.
Excavation and removal of surface soil contamination in the
Effingham residential area as called for under the March 1992
order has not been completed because the home owners in the two-
block residential area south of the Effingham Playground have not
allowed access to their properties. Residents expressed a desire
to know the full extent of cleanup that would be required in this
remedial action before allowing a portion of the work to proceed
on their properties.
The major components of the selected remedy include:
Excavation in residential areas of surface soil not
addressed under the March 1992 Order and subsurface
soil in residential areas, including the Washington
Park Housing Project, the Effingham residential area,
the Seventh Street row homes, and the Effingham
Playground, where lead concentrations exceed 500
milligrams per kilogram (mg/kg); excavation will extend
to the depth of the water table (approximately three to
six feet below the surface).
Excavation of contaminated soil around the foundations
and beneath homes and residential units (i.e.,
Washington Park Housing Project units); geotechnical
investigations will be performed during the Remedial
Design to determine the appropriate measures to be
taken during excavation to maintain the structural
integrity of each home or residential unit; residents
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will be temporarily relocated while excavation is
underway in the immediate vicinity of their home or
residential unit; sampling of the interior of homes
will be performed before, during, and after excavation
to ensure that dust control measures have been
effective.
Excavation of soil from non-residential properties,
including soil beneath areas currently covered with
asphalt (e.g., the Abex and McCready Lots) where lead
concentrations either exceed 500 nig/kg in the surface
(0 - 12") or exceed 1000 mg/kg in the subsurface (>
12"); excavation of subsurface soil will extend to the
depth of the water table (approximately three to six
feet below the surface).
Placement of clean backfill in all excavated areas;
restoration of formerly vegetated areas to the
conditions existing prior to excavation, to the extent
practicable.
Stabilization by mixing excavated soil and waste
material that exhibit toxicity using the Toxicity
Characteristic Leaching Procedures (TCLP) with
chemicals/reagents; mixing will be contained in above-
ground equipment onsite to create a final product that
encapsulates and immobilizes lead and other metals;
specific chemicals to be used in the process will be
determined in a treatability study during the Remedial
Design phase of this project; treated material will be
tested using TCLP to ensure it no longer exhibits toxic
characteristics.
Transportation of treated soils and waste material and
disposal offsite in an approved Resource Conservation
and Recovery Act (RCRA) Subtitle D landfill;
contaminated soils that do not exhibit toxicity using
TCLP may be disposed of in an approved RCRA Subtitle D
landfill, without treatment.
Demolition of all structures associated with the
foundry operations; debris exhibiting toxicity using
TCLP will be decontaminated in accordance with current
Land Disposal Restriction requirements; debris will be
disposed of in approved RCRA landfill; decontamination
of equipment stored by the current owner in
contaminated structures may also be required.
Air monitoring during onsite activity and
implementation of dust control and other necessary
abatement actions to prevent exposure of local
residents to contamination during the remedial action.
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V. STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the
environment, complies with Federal and State requirements that
are legally applicable or relevant and appropriate to the
remedial action, and is cost-effective. The remedy utilizes
permanent solutions and alternative treatment technologies to the
maximum extent practicable, and satisfies the statutory
preference for remedies that employ treatment that reduces
toxicity, mobility, or volume as a principal element. Because we
do not anticipate that this remedy will result in hazardous
substances remaining onsite above health-based cleanup levels
(i.e, 500 mg/kg in residential areas, 500 mg/kg in the surface
and 1,000 mg/kg in the subsurface soil in non-residential areas),
the five-year review will not apply to this action. If hazardous
substances are found in concentrations that exceed cleanup levels
below the practicable limits of excavation at the water table
and, therefore, cannot be excavated, the five-year review will
apply to this action.
Edwin B. Erickson
Regional Administrator
Region III
Environmental Protection Agency
SEP 29 1992
Date
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RECORD OF DECISION
ABEX CORPORATION SITE
DECISION SUMMARY
I. SITE NAME.LOCATION AND DESCRIPTION
The Abex Corporation Site (hereafter referred to as "the
Site11) is located in the eastern. section of Portsmouth, Virginia,
approximately 1.2 miles southwest of the confluence of the
southern and eastern branches of the Elizabeth River (See Figure
1). The Site encompasses a several block area with numerous
parcels of land (See Figure 2). The Site contains the former
Abex brass and bronze foundry, which is comprised of five
buildings (hereafter referred to as the Holland Property), and
associated former waste sand disposal areas (hereafter referred
to as the Abex Lot and the McCready Lot). Other areas within the
approximate 700-foot Site radius that were found to have
contamination associated, at least in part, with the former
foundry operation will be addressed in this remedial action.
The location of the Site properties are described as
follows: the Holland Property is located in the block bounded on
the east by Seventh Street, on the south by Randolph Street, on
the west by Green street, and on the north by Brighton Street;
the Abex Lot is located immediately north of the Holland
Property; the Washington Park Housing Project is located both
northeast of the Holland Property and north of the Abex Lot; the
Effingham Playground is located west of the of the Holland
Property; private residential properties (hereafter referred to
as the Effingham residential area) are located south of the
playground and southwest of the Holland Property; a drug
rehabilitation center and a small shopping center are located
south of the Holland Property; the McCready Lot is located
southeast of the Holland property at the northwest intersection
of Randolph and Seventh Streets; several row homes are located
north of the McCready Lot and immediately east of the Holland
Property; and several vacant lots are located east of Seventh
Street. The Washington Park Housing Project, the Effingham
Playground, and the Effingham residential area are currently
zoned for residential use by the City of Portsmouth. The
remaining properties are zoned for commercial and light
industrial use.
The Remedial Investigation (RI) for OU1 identified lead as
the primary contaminant of concern at the Site. Lead was
detected in soils on the Holland Property, under the asphalt-
capped Abex and McCready Lots, and in surrounding residential and
non-residential areas at levels that pose an actual or potential
threat to human health and the environment.
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o
00
70 73
Qo
T C
FIGURE 1 - SITE LOCATION MAP
N
FOUNDRY SAND DISPOSAL AREA PORTSMOUTH
FORMER LOCATION OF ABEX FOUNDRY
SOURCE: USCS 7.5 MINUTE QUADRANGLE
FOR NORFOLK SOUTH VIRGINIA.
DATED 1965. AND PHOTOREVISED
1958.
1000 0 1000 2000 3000
SCALE IN FEET
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FIGURE 2 - MAP OF SITE FEATURES
LEGEND
in
9CM£: 1" - 300'
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II. SITE HISTORY AND ENFORCEMENT ACTIVITIES
A brass and bronze foundry operated at the Site from 1928 to
1978. The foundry melted used railroad car journal bearings which
were over 80% bronze and poured the molten material into sand
molds to cast new railroad car bearings. These sand casts
eventually became laden with heavy metals, such as lead,
antimony, copper, tin, and zinc. During operation, the foundry
also produced stack emissions of fine particulate material
associated with facility processes.
The National Bearing Metal Corporation purchased the foundry
property in May of 1927 and operated the foundry at the Site from
1928 until December of 1944. American Brake Shoe Company bought
the foundry in December of 1944 and operated it until May of
1966. At that time, Abex purchased the facility and operated the
foundry until it closed in 1978. During Abex's operation of the
foundry, waste sand was disposed of in an approximately one acre
area immediately north of the foundry building. When the foundry
operation closed, Abex graded this disposal area, which is
referred to as the Abex Lot, and secured it with a seven foot
cyclone fence. Pneumo Abex Corporation, the successor of Abex
Corporation, still owns most of the Abex Lot. In 1977, Runnymede
Corporation, a real estate investment company, purchased a small
parcel of the Abex Lot from Abex. Runnymede still owns this
parcel, but no further development has occurred.
In 1984, Holland Investment and Manufacturing Corporation
purchased the portion of the Site that contains the foundry
building and several smaller associated structures. Holland
Investment and Manufacturing Corporation allowed John C. Holland
Enterprises, Inc., which is a trash hauling business, to conduct
vehicle service and maintenance on the property.
During operation and following closure of the foundry, many
of the parcels located nearby have changed ownership and have
been redeveloped for other uses. These areas include the
Washington Park Housing Project, the drug rehabilitation center,
the Effingham Playground, and numerous private residences.
In January of 1983, an EPA contractor visited the Site to
observe the conditions at the Abex Lot. No sampling was
conducted during this preliminary assessment. EPA contractors
returned to the Site in June of 1984 to perform a site inspection
and collect several samples from the Abex Lot. Sample results
detected high levels of lead (up to 10,400 mg/kg), zinc, copper,
tin, and antimony. A sample, which was to serve as an indication
of the background concentration of lead in the soil, was
collected east of the Site and also had a lead concentration of
2,750 mg/kg.
In April of 1986, EPA collected additional soil samples from
the Washington Park Housing Project and other properties
adjoining the Abex Site. The analytical results found lead
concentrations of up to 12,800 mg/kg in the samples collected.
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Pursuant to the authority granted in Section 106 of CERCLA, 42
U.S.C. §9606, EPA entered into a Consent Order with Abex in
August of 1986 for the excavation and removal of contaminated
soil at varying depths (generally 6 to 12 inches) from certain
residential areas around the Abex Lot. The areas to be addressed
included portions of the Washington Park Housing Project, the
Effingham Playground, and the Seventh Street row homes. All
excavated areas were filled with clean soil and revegetated.
Abex also paved and fenced the Abex Lot and the McCready Lot.
The analytical data collected at the Site were used to
evaluate the relative hazards posed by the Abex Site using EPA's
Hazard Ranking System (HRS). EPA uses the HRS to calculate a
score for hazardous waste sites based upon the presence of
potential and observed hazards. If the final HRS score exceeds
28.5, the site is placed on the National Priorities List (NPL),
making it eligible to receive Superfund monies for remedial
cleanup. An HRS score of 36.53 was calculated for the Abex Site.
As a result, EPA proposed the Abex Site for inclusion on the NPL
on June 24, 1988 (53 FR 23988). The Site was placed on the list
on August 28, 1990 (55 FR 35502).
On June 2, 1989, pursuant to Section 122 of CERCLA, 42
U.S.C. §9622, EPA issued Special Notice Letters to Abex
Corporation and the Holland Investment and Manufacturing
Corporation (hereafter referred to as "Holland Investment")
offering them the opportunity to perform the RI/FS for the Site.
On October 10, 1989, the VDWM, serving as the lead agency,
entered into an Administrative Order on Consent with Abex
pursuant to Section 106 of CERCLA, 42 U.S.C. §9606. Under the
terms of the Order, Abex agreed to conduct the RI/FS at the Site
to determine the nature and extent of Site contamination and to
identify remedial alternatives for Site-related contamination of
concern.
Based on the findings of the draft RI/FS report submitted in
October of 1991 and the final RI/FS report dated February of
1992, EPA determined that lead contaminated surface soil
exceeding 500 ing/kg within the Effingham residential area, and at
a few additional locations in the Washington Park Housing Project
and the Effingham Playground, presented a short-term threat to
human health. As a result, pursuant to Section 106 of CERCLA, 42
U.S.C. §9606, EPA issued a Unilateral Administrative Order on
March 30, 1992 to Abex requiring Abex to remove such soils from
the Site. Abex agreed to perform the removal action and, to
date, has excavated and removed additional contaminated surface
soil in the Washington Park Housing Project and the Effingham
Playground. Removal of soil in the Effingham residential area
has been temporarily suspended because the impacted residents
have not allowed access to their properties pending issuance of
'this document.
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III. HIGHLIGHTS OF COMMUNITY PARTICIPATION
EPA has several public participation requirements that are
defined in Sections 113(k) (2) (B), 117, and I21(f)(l)(6) of
CERCLA, 42 U.S.C. §§9613(k) (2) (B) , 9617, and 9621(f) (1) (G) ,
respectively. The documents which EPA used to develop, evaluate,
and select a remedial alternative for the Abex Site have been
made available to the public in the Administrative Record
maintained at the Portsmouth Public Library (Reference Section)
and at the EPA, Region III, Philadelphia Office. The
Administrative Record is required by Section 113(k)(l) of CERCLA,
42 U.S.C. §9613(K)(l).
The RI/FS Report and the Proposed Plan for the Abex
Corporation Site were released to the public in April of 1992.
The Proposed Plan described remedial alternatives being
considered by EPA and VDWM and identified EPA's preferred
alternative at that time. The notice of the availability of the
Proposed Plan and the Administrative Record was published in The
Virainian-Pilot on April 28, 1992. This notice also invited the
public to a meeting on May 7, 1992 to discuss the Proposed Plan
with EPA and VDWM. The public was encouraged to review the
Proposed Plan and the Administrative Record files and to submit
comments on the proposed remedial alternatives to EPA and VDWM.
The public comment period was initially scheduled to be open from
April 29, 1992 through May 29, 1992, the statutorily required 30-
day period. At the request of local citizens, EPA and VDWM
extended the public comment period which formally closed on July
10, 1992.
A public meeting was held on May 7, 1992, during the public
comment period. At this meeting, representatives from VDWM and
EPA answered questions about the Site and discussed the remedial
alternatives under consideration, as well as the short-term
removal action that was about to proceed. Approximately 30
people, including residents from the impacted area, local
government officials, a representative from Pneumo Abex, and VDWM
and EPA representatives, attended the public meeting.
EPA and representatives from MaeCorp, Abex's contractor
implementing the removal action, visited homes in the Effingham
residential area after the public meeting to try to secure access
for the removal work. During these visits, EPA also provided
additional explanations about the remedial actions presented in
the Proposed Plan. After these visits, members of the Madison
Ward Civic League requested that EPA and VDWM meet with the
Effingham residents to further discuss their concerns.
Representatives from EPA and VDWM met with approximately 30
Effingham residents on May 28, 1992 and June 9, 1992 to discuss
the proposed removal and remedial actions and the health effects
associated with lead contamination on their properties. During
this period, community awareness and concern about the proposed
cleanup activities were significantly heightened. On June 25,
1992, representatives from EPA, VDWM, the City of Portsmouth
10
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Health Department, and the Agency for Toxic Substances and
Disease Registry (ATSDR), met with approximately 60 residents at
the community center in the Washington Park Housing Project to
provide an additional opportunity for impacted residents to gain
information about the health effects of the lead contamination
and to discuss the proposed removal and remedial actions. In
addition to meetings with the local residents, VDWM and EPA met
with local officials on several occasions during this period.
As a result of the June 25, 1992, meeting, the Portsmouth
Health Department began offering free blood-lead testing to
residents in the impacted area. During July and August of 1992,
a total of 546 individuals were tested. Representatives from the
Portsmouth Health Department notified families of the test
results as they became available and advised families on
appropriate follow-up measures, where warranted.
Although the public comment period was closed, EPA held a
fifth meeting with the local community at the request of the City
of Portsmouth Mayor and City Council. The meeting was held on
August 26, 1992. Representatives from the City of Portsmouth
Health Department, ATSDR, VpWM, and EPA addressed questions from
approximately 150 local residents about health effects of lead
contamination and the proposed cleanup of the Site.
Responses to the comments received during the public comment
period are included in the Responsiveness Summary, which is part
of this ROD. This decision document presents the selected
remedial action for the Abex Corporation Site in Portsmouth,
Virginia, chosen in accordance with CERCLA, as amended by SARA,
and, to the extent practicable, the NCP. The decision for this
Site is based on the Administrative Record. The index for the
Administrative Record is included in Appendix A of the ROD. This
decision is also based upon comments received by VDWM and EPA
during the public comment period, which are included in the
Administrative Record.
iv. SCOPE Afjp PQLE OF FESPONSE ACTION
As with many Superfund sites, the problems at the Abex
Corporation Site are complex. As a result, EPA and VDWM have
organized the work into two operable units (OUs). These OUs are:
OU1: Contamination in the soil and waste sands on the
Holland Property, the Abex Lot, the McCready Lot and in
the surrounding properties within an approximate 700-
foot radius of the foundry facility
OU2: Potential contamination of the shallow and deep
aquifers, ecological impacts, including further
investigation and analysis of surface and sediment
quality, and additional soil contamination that may
exist beyond the approximate 700-foot radius being
addressed in OU1.
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The first OU, the subject of this ROD, addresses lead
contamination in soil. The primary exposure pathway of concern
at this Site is incidental ingestion of soil. Based on results
of the EPA'a Lead Uptake Biokinetic Model, children are exposed
to an unacceptable health risk when the average lead
concentrations in surface soil exceeds 400 mg/kg. The purpose of
this response is to protect, huma* health and the environment by
preventing current or future exposure to the contaminated soil.
As part of OU2, additional RI/FS activity vill be performed
to fully characterize the nature and extent of ground water
contamination. This OU will also include an investigation of
additional soil contamination at distances greater than 700 feet
from the foundry facility, as well as offsite ecological impacts.
V. SUMMARY OF SITE CHARACTERISTICS
GENERAL OVERVIEW
The Abex Site is located in the urban environment of
Portsmouth, Virginia, approximately one-half mile to the west of
the south branch of the Elizabeth River. The Site is relatively
flat and is approximately 5 to 10 feet above mean sea level. A
review of aerial photographs from 1937 reveals extensive
surficial drainage surrounding the Site. However, by 1964,
drainage was largely confined to Gander Creek, a channelized
canal flowing from east to west just north of the Abex Lot. At
the present, most drainage occurs through a network of catch
basins and storm sewers.
The Abex Site is located in one of the oldest sections of
the City of Portsmouth. The area was incorporated into the
City's limits in 1784. The U.S. Naval Shipyard, located less
than a mile to the southeast, commenced operation in 1767 and
presently encompasses about 800 acres. The Portsmouth area
experienced rapid growth during World Wars I and II when the Navy
expanded its shipyard, hospitals, and docking facilities.
The population in the one-mile radius surrounding the Site
varied during the period when the foundry was operating. From
1930 to 1950, the population in this area grew from 27,470 to
30,930. Subsequent to 1950, the population declined to 27,575 in
1960; 19,940 in 1970; and 15,117 in 1980.
The Elizabeth River Basin, which surrounds Norfolk,
Portsmouth, and Chesapeake, drains approximately 300 square
miles. The river basin is heavily industrialized and receives
wastewater discharges from U.S. Naval facilities, heavy industry,
major municipal treatment facilities, urban runoff, and boating
and docking facilities.
Annual rainfall in the Site area is between 45 and 50
inches. Wind direction for the Portsmouth and the surrounding
area is predominantly north-northeast and south-southwest.
12
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Generally interpreted, the former foundry property and the
surrounding 700-foot radius study area are underlain by a veneer
of undistinguished fill material, sand, and fine grained
sediments. Groundwater movement beneath the study area is
largely confined to the sand-dominated strata.
Portsmouth lies in the Coastal Plain physiographic province
and, in general, is underlain by a thick sequence of
unconsolidated sediments consisting primarily of sand, gravel,
silt, clay and some shell material. These sediments thicken from
west to east in a wedge-like form and are immediately underlain
by igneous and metamorphic bedrock. The depositional history of
the unconsolidated sediments is complex and has resulted in what
is generally an alternating sequence of sand and fine grain
sediment layers.
In the vicinity of Portsmouth, large-scale groundwater
movement occurs only within the confined aquifer formations.
Except for the uppermost aquifer, the Columbia Group, each
aquifer is separated from the underlying aquifer by a confining
unit. Most of the ground water used in the area for potable
purposes is withdrawn from the confined aquifers. At the present
time, very little ground water withdrawn from the unconfined
Columbia Group aquifer is utilized for potable purposes.
SUMMARY OF RI FINDINGS
The primary focus of the RI was to evaluate possible lead
contamination in soil on and around the foundry property. In
addition, the RI included a limited investigation of ground
water, surface water, and sediments potentially impacted by the
Site.
Soil contamination was investigated by sampling and testing
over 1,000 samples for lead content. Of these samples, over 550
were also analyzed for fourteen other metals. Soil samples were
collected either using a hand auger or through soil borings. A
total of 206 locations were sampled using the hand auger. Sample
locations were established primarily through use of a 100-foot
grid system over the 700-foot radius study area. At each
location, a minimum of two samples were collected - one at the 0
to 0.5 foot depth and a second at the 1.5 to 2 foot depth.
Additional samples were collected to a maximum depth of 3 to 3.5
feet where elevated lead concentrations were observed.
'Soil borings ranging in depth from 11 to 26 feet were
performed at 34 locations primarily in the Abex Lot and on and
around the Holland Property. A minimum of five samples were
collected at each location to characterize the stratigraphy of
the water table aquifer. The number of samples analyzed varied
depending on the location and the conditions encountered. Most
analyses were for lead or for the primary pollutant list of
fourteen metals.
13
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Sweep samples for dust were also collected from the interior
of the foundry building and from the attics of two Seventh Street
row homes. A number of the dust and soil samples collected on
the Holland Property and in the Abex Lot were analyzed for the
complete list of priority pollutants.
The major finding of the RI at the Site was that both
surface and subsurface soils are contaminated with lead in
residential and non-residential areas. Soil ("floor dirt") and
dust throughout the interior of the foundry building on the
Holland Property was found to contain lead levels of up to
100,000 mg/kg. Outdoor soil on the Holland Property contains
lead levels of up to 58,000 mg/kg within the top two feet. Waste
sand beneath the asphalt cap on the Abex Lot has lead
concentrations ranging up 24,000 mg/kg. Lead levels of up to
4,750 mg/kg occur within the top two feet of soil under asphalt
within the McCready Lot.
Surrounding areas containing lead-contaminated soil
associated with the Site include portions of the Washington Park
Housing Project, the Effingham Playground, the Effingham
residential area, the Seventh Street row homes, the drug
rehabilitation center property, and vacant lots east of Seventh
Street.
Lead levels of up to 46,500 mg/kg were detected in soil at
depths of one to four feet in portions of the Washington Park
Housing Project. Subsurface soil in the Effingham Playground
contains lead levels up to 5,000 mg/kg. Contaminated surface
soil (generally 6 to 12 inches) in both Washington Park and the
Effingham Playground were previously excavated and removed by
Abex pursuant to a Consent Order signed with EPA in August 1986.
A few additional areas in the Washington Park Housing Project and
the Effingham Playground were identified during the OU1
investigation as having surface soil contamination above 500
mg/kg. Soil in these areas was excavated and removed by Abex
pursuant to a Unilateral Order issued by EPA in March of 1992.
Surface and subsurface soil within the Effingham residential
area have lead concentrations of up to 8,000 mg/kg. Additional
sampling performed as part of the 1992 removal action detected
elevated levels of lead ranging up to 3,739 mg/kg in crawl spaces
beneath eleven of sixteen homes sampled in this area.
Soil in lots associated with the Seventh Street row homes
contain lead at levels up to 7,000 mg/kg at 0 to 2 feet in depth.
Surface soil contamination in the row home lots was previously
addressed by Abex under the 1986 Consent Order. Attics of two
Seventh Street homes contain dust with lead levels of up to 7,030
mg/kg.
Surface soil within the drug rehabilitation center property
contains lead at levels of up to 9,300 mg/kg. Lead has also been
detected in surface soil of the vacant lots east of Seventh
Street at levels of up to 1,200 mg/kg, with subsurface soils
14
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containing lead of up to 6,000 ing/kg.
A limited hydrogeologic investigation was undertaken at the
Site to assess the impact of contamination on the surficial
aquifer. Four monitoring wells, three piezometers, and numerous
soil borings were installed to gain an understanding of the
materials and contaminant distribution in the upper aquifer. Two
monitoring wells were located in the Abex Lot; one well was
located in the McCready Lot; and one well was located immediately
north of the Seventh Street row homes. The wells were drilled to
approximately fourteen feet below ground surface; the piezometers
were drilled to fifteen feet below ground surface. Groundwater
was encountered from three to six feet below surface across the
Site.
Groundwater data from the Abex property indicates that lead
has entered the surficial groundwater in the source area either
through migration or through past disposal practices. Elevated
concentrations of lead were present in filtered samples collected
in one of the monitoring wells in the Abex Lot (MW-1). Lead
levels of 31 micrograms per liter (ug/1) and 24 ug/1 were
detected during two separate sampling events. EPA recommends a
cleanup level of 15 ug/1 for lead in ground water. Filtered
samples collected in the other three wells did not exhibit
elevated concentrations of lead. The surficial aquifer and the
deeper aquifer are not currently used for drinking water supplies
in the area of the Site. Further investigation of contamination
in the deeper aquifer and the hydraulic relationship between the
surface and deeper aquifers will be undertaken as part of OU2.
Surface water and sediment samples were collected from four
catch basins within the 700-foot study area. Elevated metal
concentrations were observed in both surface water and sediment
samples. The significance of the metal concentrations detected
and the relationship of these concentrations to the Abex Site is
unclear. Further investigation and analysis of surface water and
sediment quality at the Site, including potential ecological
impacts, will be performed as part of OU2.
VI. SUMMARY OF SITE RISKS
An assessment of the potential risks posed to human health
and the environment was completed in accordance with the NCP.
Specifically, the baseline risk assessment provides the basis
for taking action and indicates the exposure pathways that need
to be addressed by the remedial action. It identifies the risks
that could exist if no action were taken at the Site. The
baseline risk assessment for the Abex Site was completed in
February of 1992 and is part of the Administrative Record.
In general, a baseline risk assessment is performed in four
steps: (1) data collection and evaluation, (2) the exposure
assessment, (3) the toxicity assessment, and (4) risk
characterization. This section of the ROD will summarize the
15
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findings during each of these steps of the baseline risk
assessment for the Abex Site.
IDENTIFICATION OF CONTAMINANTS OF CONCERN
Lead is the contaminant of principal concern at this Site
due to its known health effects and its widespread presence in
surface and subsurface soil in the residential areas, as well as
the foundry properties, other contaminants present, along with
lead, at levels of concern in residential areas include antimony,
nickel, tin, copper, and zinc. These contaminants are all known
to be present in the waste sands from the foundry operation.
Other contaminants present at levels of concern on the Holland
Property, the Abex Lot, or the McCready Lot include cadmium,
chromium, silver, and polynuclear aromatic hydrocarbons (PAHs),
and polychlorinated biphenyls (PCBs).
The two media of primary concern at this Site are soil and
ground water. An overview of the extent of contamination in the
soil at the Site is presented in Table 1. The data are presented
for the three residential areas - the Washington Park Housing
Project, the Effingham residential area, and the Seventh Street
row homes; for the Effingham Playground; for the foundry
properties including the Holland Property, the Abex Lot, and the
McCready Lot; and for the vacant lots. The number of samples
collected (designated as "n"), the mean (or average)
concentrations, and the upper 97.5 percentile confidence limit
concentrations are presented in Table 1 for both surface soil
(0 - 12") and subsurface soil (> 12") data. The term "upper 97.5
percentile confidence limit" is a statistical term used in
describing how well the data collected reflect actual conditions.
There is a 97.5% probability (i.e., 39 times out of 40) that the
actual mean concentration for the contaminant of concern listed
is below the the upper confidence limit value.
Since lead is relatively immobile in the environment, the
ground water investigation in the OU1 RI was limited to four
wells in the surficial aquifer. Ground water in the surficial
aquifer was found to exceed the EPA's recommended cleanup level
for lead in one well which was located in the Abex Lot. The
surficial aquifer and the deeper confined aquifer are not
currently used for drinking water supply. Further investigation
of potential ground water contamination will be performed as part
of the OU-2 investigation to assess potential future risk and the
need for possible remediation. The discussion of site risks
presented below will focus on contamination in the soil media.
16
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TABLE 1
AREA:
EXTENT OF SOIL CONTAMINATION AT THE ABEZ SITE
SURFACE SOIL
n
MEAN
<»g/kg)
97.5th
% UCL
(ag/kg)
SUBSURFACE SOIL
n
MEAN
(mg/kg)
97.5th
% UCL
(mg/kg)
Washington Park Housing Project:
Lead
Antimony
Copper
Nickel
Tin
Zinc
135
6
6
6
6
6
260
7
311
7
55
315
289
10
565
13
89
560
93
77
77
77
77
77
Effingham Residential Area:
Lead
Antimony
Copper
Nickel
Tin
Zinc
48
25
25
25
25
25
1302
8
546
16
152
896
1,688
10
736
23
224
1,175
38
15
15
15
15
15
2,926
22
2,079
26
580
1,979
20,744
138
14,698
146
4,314
12,607
1,545
14
411
28
490
1,482
8,632
54
1,541
103
1,872
4,503
Seventh street Rov Homes:
Lead
Antimony
Copper
Nickel
Tin
Zinc
0
0
0
0
0
0
...
...
...
...
...
...
...
...
...
...
29
29
29
29
29
29
974
9
902
14
200
500
8,834
41
9,452
90
1,962
4,852
Effingham Playground:
Lead
Antimony
Copper
Nickel
36
5
5
5
267
6
407
6
326
6
1,200
12
34
32
32
32
1,869
12
803
33
8,526
53
4,279
186
17
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TABLE 1 - EXTENT OF SOIL CONTAMINATION AT THE ABEX SITE
AREA:
ContflBiiaflnt
SURFACE SOIL
n
MEAN
(»g/kg)
97.5th
% UCL
(mg/kg)
SUBSURFACE SOIL
n
MEAN
(mg/kg)
97 . 5th
% UCL
(mg/kg)
Eff ingham Playground (Cent. ) :
Tin
Zinc
5
5
63
381
132
754
32
32
423
1,503
2,117
6,836
Holland Property/Abex Lot/McCready Lot:
Lead
Antimony
Cadmium
Chromium
Copper
Nickel
Silver
Tin
Zinc
Total
PAHs
Total
PCBs
41
33
33
33
33
33
33
33
33
340
14
33,000
590
15
185
54,000
255
18
2,872
8,400
29
5
46,800
928
21
256
90,400
397
26
4,261
11,800
32
12
46
45
41
44
45
45
39
45
45
1
3
Vacant Lots/Drug Rehabilitation Center:
Lead
Antimony
Copper
Nickel
Tin
Zinc
86
22
22
22
22
22
609
7
619
10
100
549
848
9
1072
14
154
743
101
30
30
30
30
30 '
8,937
104
4
12
15,055
71
5
1,861
3,290
0.099
13.5
849
18
852
16
298
962
44,954
659
18
38
87,866
395
26
12,720
14,658
45.4
7,345
141
5,803
67
1,738
5,286
KEYS
97.5XUCL
the nunber of saaplea collected
the average concentration of the Maples collected; units are
illigran per kilograa
Upper Confidence Liait; the concentration at which there is a
97.5 X probability that the actual aean concentration ia below
18
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HUMAN HEALTH EXPOSURE ASSESSMENT
The purpose of the exposure assessment in the baseline risk
assessment is to determine exposure pathways that exist at a site
and to quantify the exposure associated with each pathway. An
exposure pathway exists if there are: (l) contaminants at a site
at levels of concern; (2) individuals that may come in contact
with those contaminants; and (3) mechanisms by which
contamination can enter the body.
The potentially exposed populations for OU1 consist
principally of residents (children and adults) within
approximately 700 feet of the foundry who are exposed to soil
containing the contaminants of concern discussed above. The risk
assessment also considered the potential exposure to adults
working in the former foundry building, although this type of
exposure is not presently occurring.
Actions at Superfund sites should be based on an estimate of
the reasonable maximum exposure expected to occur under both the
current and future land-use conditions. The reasonable maximum
exposure is defined as the highest exposure that is reasonably
expected to occur at a site. The risk assessment for the Abex
Site was based on the assumption that current and future land use
in the area are not expected to change significantly.
The current land use at the Site is a mixture of residential
and commercial/light-industrial. The Washington Park Housing
Project, the Effingham residential area, the Seventh Street row
homes, and the Effingham Playground are currently zoned for
residential use (See Figure 3). The Abex Lot, Holland Property,
and McCready Lot, the drug rehabilitation center, and the vacant
lots are zoned for use as commercial/light-industrial purposes.
Future use is expected to remain the same for the residential
properties. The Holland Property, the Abex Lot, and the McCready
Lot are expected to be used for commercial or light industrial
purposes in the future. The drug rehabilitation center is
expected to continue operation at its current location. The
properties with the greatest uncertainty as to their future use
are the vacant lots east of Seventh Street. Most of the vacant
lot area is located outside of the 700-foot study area for OU1.
The City of Portsmouth had originally planned a 60-acre
PortCentre Business Park in this area, however, a GSA project
which was the cornerstone of this development was awarded to
another city. The city of Portsmouth is currently considering
other options for this 60-acre parcel located just outside of the
700-foot radius, including construction of a new high school.
Routes of exposure considered in the risk assessment include
soil ingestion, dermal contact, food ingestion, dust inhalation,
inhalation of vapors. These pathways are described briefly
below:
Soil ingestion Eating soil and dust, usually
inadvertently and probably arising
19
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Dermal contact
Food ingestion
Dust inhalation
Inhalation of vapors
mostly from the soil being transferred
from hand to mouth
Skin contact with soil and dust
Eating locally grown foods not
thoroughly washed to remove contaminated
soil
Breathing dust; no industrial dusts are
currently being generated through active
operations, nor are any expected to be
generated in future; dust may come from
disturbed contaminated soil in the area
Breathing vapors from ground water and
soil; route of exposure was found to be
negligible
To quantitatively evaluate the exposure associated with
pathways identified at the Site, assumptions were made concerning
the reasonable maximum exposure for an individual living in the
impacted area. Table 2 presents the activity pattern for exposed
residents and the assumptions made as part of the risk
assessment. This table was designed to reflect potential
activities for a resident that would result in relatively high
exposure to the contaminants of concern in the soil. Different
activities were assigned reasonable average weekly times. All
activities were assumed to take place for 350 days per year.
TABLE 2 - ACTIVITY PATTERNS FOR EXPOSED RESIDENTS
ACTIVITY
At home
indoors
At home
outdoors
Foundry site
At school
off-site
Activities
off-site
HOURS/WEEK (By Age category)
0-1
130
35
0
3
1-4
130
35
0
3
4-7
131
33
1
3
7-11
102
33
1
29
3
11-15
102
33
1
29
3
15-18
102
33
1
29
3
18-70
131
33
1
3
Source: Baseline Risk Assessment for the Abex Site, Table 3.7
20
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FIGURE 3 - SITE ZONING MAP
RM-60 - Single fanily residentail detached hoses (6,000 sq ft).
M-l - Industrial district tor wholesale, warehouses, light
industrial, etc.
c-2 - General coaaercial district (large scale stores, strip
alls, departBent stores, etc).
C-l - Neighborhood coaaercial retail trade
3R-75 - office residential district (doctors, dentist, etc)
»-z - Heavy industrial distict
I
21
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As part: of the process to quantify exposure, standard
assumptions are made concerning factors such as the intake rate
for soil ingestion, the ability of soil to adhere to skin,
inhalation and consumption rates, the average lifetime, and
maximum periods of exposure. Table 3 summarizes the exposure
factors used in the risk assessment for the Abex Site.
The final consideration in quantifying exposure is the
concentration of the contaminant of concern to be used in the
calculation. The risk assessment for the Site used data from
soil samples collected in the top six inches to calculate
exposure concentrations. Surface soil data was used since
residents are exposed to these soils at a much greater frequency
than subsurface soil. The mean concentration and the upper 97.5
percentile confidence limit were calculated for each contaminant
of concern in each area of the Site, as presented in Table 1.
The upper confidence limit values were used to quantify
individual exposure.
HUMAN HEALTH TOXICITY ASSESSMENT
The purpose of the toxicity assessment is to weigh available
evidence regarding the potential for particular contaminants to
cause adverse effects in an exposed individual. Where possible,
the toxicity assessment provides an estimate of the relationship
between the extent of exposure to a contaminant and the increased
likelihood and/or severity of adverse effects. The first step in
the process is to determine whether exposure to the contaminant
can cause an increase in the incidence of either a cancer-related
(carcinogenic) or non-cancer-related (noncarcinogenic) adverse
health effect. EPA gathers evidence from a variety of sources
regarding these health effects including controlled epidemiologic
investigations, clinical studies, and experimental animal
studies.
The second step in the toxicity assessment is to
quantitatively evaluate the health effects associated with the
contaminant of concern on the exposed population. For
contaminants that are known or suspected of causing cancer,
Cancer Slope Factors (CPFs) have been developed by EPA's
Carcinogenic Assessment Group in order to estimate the adverse
health effect. Carcinogenic effects are measured as the
additional risk of an individual contracting cancer as a result
of exposure to. potentially carcinogenic chemicals. CPFs are
multiplied by the estimated exposure rates to provide an upper-
bound estimate of the excess lifetime cancer risk associated with
that exposure. The term "upper bound" reflects the conservative
estimate of the risks and makes underestimation of the actual
cancer risk highly unlikely. Table 4 lists the CPFs for the
chemicals treated in this risk assessment.
For contaminants that are not known to cause cancer,
reference doses (RfDs) have been developed by EPA for quantifying
the potential for adverse health effects from exposure. RfDs are
22
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TABLE 3 - EXPOSURE FACTORS
E*p03ure pathway
Inge3tion of aoil and du3t
rate mVda
Body veight Jcg (bj
Conation of h rown ^^
Homegrown vegetablea g/day
of adult -
g/day
con.tant.
0-1
Age Categories (e)
1-4 4 7
'"
30
18-70
0
1
2
100
350
0.51
.203
.645
.194
0
0
0
200
350
0.51
0 2flfi
v ft o D
4.168
5.558
13.2
9.175
1.660
0 4
V "1
200
350
Oc «
.51
0.406
6.636
8.848
19.7
9.175
1.660
0.
. 4
100 100
350 350
°-51 0.51
0.537 n fli
* u . 0 1
7.267 7.952
9-689 10.603 l
29.9 AC
^ TO
!5.263 18.350
2-762 3.320
0-665 o 8
v . y
100 100
350 350
n Q i A _ .
^u--'l 0.51
°-997 i.05
39-?24fi5 15
3.126 20
59.4 70
18.350 22.938
1 1?fl < 1 r .
J . J^U 4.151
0.8 i
years
Source: Baseline Risk Assessment
for the Abex Site, Table 3.8
23
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TABLE 4 - CANCER SLOPE FACTORS
CHEMICAL
SLOPE FACTORS (mg/kg-day) '*
ORAL
INHALATION
Metals:
Antimony
Cadmium
Chromium (VI)
Copper
Nickel
Silver
Tin
Zinc
**
**
**
**
**
**
**
**
**
6.1
41.0
**
0.84
**
**
**
DERMAL
**
**
**
**
**
**
**
**
PAHS:
Acenaphthene
Anthracene
Benzo(a)-anthracene
Benzo(a) -pyrene
Benzo(b)- f luoranthene
Benzo
-------
estimates of lifetime daily exposure levels for humans, including
sensitive individuals, who are likely to be without an
appreciable risk of adverse effects during a lifetime. Estimated
intakes of chemicals from environmental media (e.g., the amount
of a chemical ingested from contaminated soil) can be compared to
the RfD. Table 5 lists values of RfD (for chronic exposure) and
RfD (for subchronic exposure), where they are available. The
toxicity profiles discussing the possible effects of the
contaminants of concern are included at the end of this section.
EPA does not currently recommend using the standard risk
assessment methods described thus far for evaluating lead
contamination. EPA recommends, and the Abex risk assessment
used, the Uptake/Biokinetic (UBK) Model to assess the hazards
associated with lead contamination at the Abex Site. The UBK
Model estimates a range of blood lead levels for children that
can result from the overall exposure to the variety of lead
sources in the environment. The model considers possible
exposure from air, diet, drinking water, soil/dust, paint
chips/dust, and maternal blood lead sources. Table 6 presents
the standard assumptions used in the UBK model in the Abex risk
assessment. Lead exposure was evaluated for children up to four
years old, the group most sensitive to potential adverse health
effects from lead.
TOXICITY PROFILES FOR CONTAMINANTS OF CONCERN
Lead is a heavy metal that exists in one of three oxidation
states, 0, +2, and +4. Primarily, lead is used in equipment
where pliability and corrosion resistance are required, for
example, in solder, paints and varnishes, storage batteries, and
alloys. Occupational exposure to lead dust and fumes can occur
during mining, refining, smelting, and welding. Children
exhibiting pica (placing non-food items in the mouth), as well as
children exhibiting normal hand-to-mouth activities, who are
exposed to lead-contaminated paint chips, dust, or soil can
experience elevated blood lead levels, sometimes at elevations
significant enough to cause clinical illness. Some of these
effects, particularly changes in the levels of certain blood
enzymes and in aspects of children's neurobehavioral development,
may occur at low blood levels. The fetus may also be impacted by
blood levels below 10 microgramss per deciliter (ug/dL). Lead
has been classified as a Group B2 probable human carcinogen.
Oral exposure to lead salts, primarily phosphates and acetates,
has caused kidney tumors in laboratory animals.
(Note: Additional details on the health effects of lead are
presented in response to questions in'Section I of the
Responsiveness Summary.)
25
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CHEMICAL
Antimony
Cadmium
Chromium
(VT)
Copper
Nickel
Silver
Tin
Zinc
Acenaphthene
Anthracene
Benzo( a )anth r acene
Benzo(a)pyrene
Benzo(b)fluor-
anthene
Benzo
-------
TABLE 6 - STANDARD ASSUMPTIONS FOR UBK MODEL
Parameters that vary with age
0-1 1-2 2-3 3-4
Exposure from air
. Background concentration in air: 0.2 u.g/m3
Indoor air concentration (% of outdoors): 30%
Time spent outdoors (hours/day): 1234
Ventilation rate (m3/hr): 2355
Percent absorption in lung: 32%
Exposure from diet
Background dietary exposure to lead (fig/day): 5.88 5.92 6.79 6.57
Percent absorption in gastrointestinal tract: 50%
Exposure from drinking water
Lead concentration in drinking water: 4 u.g/1
Daily ingestion rate of drinking water (I/day): 0.20 0.50 0.52 0.53
Percent absorption in gastrointestinal tract: 50%
Exposure from soil/dust
Rate of soil/dust exposure (mg/day): 100
Percentage exposure to soil: 45%
Percentage exposure to dust: 55%
Percent absorption in gastrointestinal traci: 30%
Exposure from paint chips
Rate of exposure to lead in paint (mg/day): 0
Source: Baseline Risk Assessment for the Abex Site," Table 4.4
27
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TOZZCZTY PROFILES FOR CONTAMINANTS OF CONCERN (Cent.)
Antimony is a soft metal which is insoluble in water and
organic solvents. It is widely used in the production of alloys.
Oral exposure to antimony has been shown to cause burning stomach
pains, colic, nausea and vomiting in humans. Long-term
occupational inhalation exposure is associated with heart disease
in both human and laboratory animals. Decreased longevity and
altered cholesterol levels have been observed in rats. Antimony
has not been tested for carcinogenicity.
Copper is a reddish-brown metal which occurs alone or in
ores. It is insoluble in water but soluble in acid. Metallic
copper is used as a conductor of electricity and in all gauges of
wire for circuitry, as well as in coil and high conductivity
tubes. Copper is used in many important alloys, such as brass
and bronze. Copper is also used in insecticides, fungicides,
catalysts, analytical reagents, and paints. Acute exposure to
copper salts may cause eye and skin irritation. Acute industrial
exposure to copper may occur from fumes generated during welding
copper-containing metals. This type of exposure may cause upper
respiratory tract and stomach irritation. The effect of chronic
exposure to copper are rarely seen, except in individuals with
Wilson's disease. Wilson's disease is a genetic condition where
abnormal amounts of copper are absorbed and stored by the body.
Chronic exposure to copper may result in anemia. Copper is not
classifiable as to human carcinogenicity.
Cadmium is a bluish-white metal. Small amounts of cadmium
are found in zinc, copper, and lead ores. Cadmium is insoluble
in water but is soluble in acids. Cadmium dust includes dust of
various cadmium compounds. Cadmium is used as a protective
coating for iron, steel, and copper because it is resistant to
corrosion. Cadmium alloys (copper, nickel) may be used as
coatings for other materials, welding electrodes, solders, and in
pigments and paints. Cadmium is used as an amalgam in dentistry.
Various cadmium compounds are used as fungicides and
insecticides. Exposure to cadmium can occur through inhalation
and ingestion. Short and long-term inhalation exposure to
cadmium dust or fumes is associated with swelling of the lung
tissue, pain in the chest, difficulty in breathing and emphysema.
Long-term ingestion of cadmium is associated with changes and
damages to the kidneys in laboratory animals. The EPA has
classified cadmium as a Group Bl probable human carcinogen.
Cadmium may be associated with an increased risk of prostate and
lung cancer in humans occupationally exposed to this contaminant.
Chromium is a heavy metal that generally exists in either a
trivalent or hexavalent oxidation state. Hexavalent chromium is
soluble and mobile in ground water and surface water. Trivalent
chromium is in the reduced form and is generally found adsorbed
to soil, therefore, it is less mobile. Hexavalent. chromium is
used in chrome plating, copper photography, copper stripping,
aluminum anodizing, as a catalyst, in organic synthesis, and
photography. Exposure to chromium compounds can occur through
28
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ingestion, inhalation and skin contact. Hexavalent chromium may
have a direct corrosive effect on the skin and may cause upper
respiratory distress, headache, fever, and loss of weight. Long-
term occupational inhalation exposure to dust and fumes of
hexavalent chromium has been shown to cause lung cancer in
humans, especially those in the chrornate-producing industry. In
addition, a number of salts of hexavalent chromium are
carcinogenic in rats. The EPA has classified hexavalent chromium
as a Group A human carcinogen. Trivalent chromium is an
essential nutrient and has low toxicity; however, at high levels,
it may cause skin irritation.
«
Nickel is a hard white, ferromagnetic metal that is a
naturally-occurring element in the earth's crust and is stable in
the atmosphere at ambient temperatures. Nickel forms alloys with
a variety of metals including copper, manganese, zinc, chromium
and iron. Elemental nickel is used in electroplating and casting
operations, magnetic tapes, surgical and dental instruments,
nickel-cadmium batteries, and colored ceramics. Occupational
exposure to nickel compounds has been associated with an
increased incidence of nasal cavity and lung cancers. For this
reason, nickel refinery dust has been classified by the EPA as a
Group A - Human Carcinogen via the inhalation route of exposure.
The most common reaction to nickel exposure is skin
sensitization. Nickel and its compounds also irritate the
conjunctiva of the eye and the mucous membranes of the upper
respiratory tract.
Polyohlorinated biphenyls (PCBs) are complex mixtures of the
products of the chlorination of biphenyl. The mixtures contain
isomers of chlorobiphenyls with different chlorine content. PCBs
may contain other chlorinated mixtures (e.g., chlorinated
naphthalenes and chlorinated dibenzofurans). PCBs are stable and
nonflammable. They are used chiefly in insulation for electric
cables and wires. PCBs are persistent in the environment and
bioaccumulate in food chains, with possible adverse effects on
animals and man. Prolonged skin contact may cause the formation
of chloracne which is characterized by blackheads, fat containing
cysts and pustules. Irritation of eyes, nose and throat may also
occur. Systemic toxic effects are dependent upon the degree of
chlorination of the biphenyls. Short and long-term exposure may
cause liver damage. PCBs may cause embryo toxicity leading to
stillbirth. Some PCBs are carcinogenic in animals. The EPA has
classified PCBs as Group B2 probable human carcinogens. Oral
exposure to PCBs has been shown to cause liver tumors in
laboratory animals.
Polycyclic aromatic hydrocarbons (PAHs) constitute a class
of contaminants consisting of substituted and unsubstituted
,polycyclic aromatic rings formed by the incomplete combustion of
organic materials. Their physical, chemical, and biological
properties vary with their size and shape. PAHs are persistent
in the environment. Benzo (a) pyrene is one of the most common
and most hazardous PAH. Some PAHs are classified by the EPA as a
Group B2 probable human carcinogens. Benzo (a) pyrene is the
29
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most potent of the carcinogenic PAHs. Oral exposure to benzo (a)
pyrene has been shown to produce stomach tumors in mice and rats
and mammary tumors in rats. Dermal exposure to benzo (a) pyrene
has been shown to produce skin cancer in mice, rats and rabbits.
Oral and inhalation exposure to benzo (a) pyrene has been shown
to cause lung tumors in mice and rats. Long-term exposure to
PAHs may cause birth defects.
silver is a white metal insoluble in water arid soluble in
sulfuric and nitric acids. Alloys or silver (e.g., copper,
aluminum, cadmium , lead or antimony) are used in the manufacture
of silverware, jewelry, coins', films, in mirrors, as a
bactericide for sterilizing water, fruit juices, etc. Some
silver compounds are also of medical importance as antiseptics or
astringents. Exposure to silver can occur through inhalation of
fumes or dust, ingestion of solutions or dust, eye and skin
contact. Eye and skin contact with metallic silver may produce
local permanent discoloration of the skin similar to tattooing.
This process is referred to as argyria. Argyria is characterized
by a dark, slate-gray color pigmentation of the skin. Generalized
argyria can also develop through exposure to silver oxides or
salts through ingestion and inhalation of dust. Silver is not
classifiable as to carcinogenicity.
Tin is a soft, silvery white metal which is insoluble in
water. It is used as a protective coating for other metals such
as in household utensils, as soft solders, and in the packaging
industry. Exposure to tin may occur in mining, smelting, and
refining, and in the production and use of tin alloys and
solders. Inorganic tin salts are mild skin irritants. Exposure
to dust or fumes of inorganic tin is known to cause lung disease.
Tin is not classifiable as to human carcinogenicity.
Zino is a bluish-white metal that is stable in dry air, but
becomes covered with a white coating on exposure to moist air.
Zinc is present in abundance in the earth's crust. Zinc chloride
is used as a wood preservative, in dry battery cells, in oil
refining operations, and in the manufacture of dyes, activated
carbon, deodorants and disinfecting solutions. Zinc chromate and
zinc oxide are used primarily as pigments. Exposure to zinc
compounds can cause skin sensitization, irritation of the nose
and throat, fever, and fatigue. Zinc is not classifiable as to
human carcinogenicity.
HUXAH HEALTH RISK CHARACTERIZATION
The risk characterization section in a risk assessment
summarizes the results of the exposure and toxicity assessments
to describe the baseline risk for the Site. In general, risk is
characterized as being unacceptable when (1) existing levels of
contaminants present at the site may cause cancer or some other
adverse health effect; (2) there is a route or pathway through
which a receptor may be exposed (e.g., ingestion of contaminated
soil); and (3) there is a receptor which may be exposed (e.g., a
30
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child ingesting soil). For cancer-causing contaminants, risk is
measured as the number of additional incidences of cancer that
can be expected in an population exposed to that contaminant.
For example, one additional incident of cancer estimated to occur
in a population of 10,000, as a result of exposure to
contamination at a site, would quantitatively be described as a 1
x 10"* cancer risk. EPA recommends that remedial actions be
taken to address risk greater than a 1 x 10"* cancer risk. EPA
may recommend action in situations where the risk is in the range
of 1 x 10"4 to 1 x 10"6 (one additional incident of cancer in a
population of 1,000,000).
For noncarcinogenic contaminants, risk is considered
unacceptable when the concentration of the contaminant that an
individual is exposed to (i.e., the intake rate) exceeds the RfD
concentration for that contaminant. The noncarcinogenic effects
of a single contaminant in a single medium is expressed as the
hazard quotient (HQ). To assess the overall potential for
noncarcinogenic effects posed by more than one contaminant, the
HQs are added to determine the Hazard Index (HI). The HI
provides a useful reference point for gauging the potential
significance of multiple contaminant exposure within a single
medium or across media. EPA may recommend action in situations
where the HI exceeds one.
Table 7 summarizes the quantitative results of the risk
assessment for residents and workers exposed to contaminants of
concern other than lead at the Site. In the case of residential
exposure, risks to different age groups were determined.
EPA does not recommend characterizing the health effects
associated with lead using the risk assessment procedures
discussed above. EPA currently believes that the best available
approach for characterizing risks associated with lead in
residential areas is the UBK Model. The UBK Model was used at
the Abex Site to predict the percentage of highly exposed
children that would have a level of lead in their blood exceeding
10 ug/dL, the level recommended as safe by the Center for Disease
Control (CDC), at various levels of contamination. Based on the
exposure assumptions presented earlier, the model predicts that
approximately 95 percent of the children exposed to soil/dust
with an average lead concentration of 400 mg/kg would have blood
lead levels below 10 ug/dL.
The baseline risk assessment for the Abex Site has
determined that contamination at the Site currently presents
unacceptable risks to residents and would pose unacceptable risks
to workers within the former foundry building. The average lead
concentration exceeds 400 mg/kg in surface soil in the Effingham
residential area, on the Holland Property, and in the vacant
lots. Average lead concentrations also exceed 400 mg/kg in
subsurface soil in the Washington Park Housing Project, the
Effingham residential area, the Seventh Street row homes, the
Holland Property, the Abex Lot, the drug rehabilitation center,
and the vacant lots.
31
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The baseline risk assessment also indicates that children
between the ages of one and seven and future workers at the
former foundry building would be exposed to unacceptable risks
associated with other noncarcinogenic contaminants of concern.
This is indicated in Table 7 where the total HI values are
greater than one. It should be noted, however, that the HI
calculations may overestimate the potential for adverse health
effects at the Site since not all contaminants of concern induce
the same health effect by the same mechanism of action.
The total lifetime cancer risks associated with the Site are
3.0 x 10"5 for residents (i.e., one additional incident of cancer
in an exposed population of 33,333) and 8.97 x 10~4 for future
workers at the former foundry facility (i.e., one additional
incident of cancer in an exposed population of 1,115).
TABLE 7 - BA
EXPOSED POPULATION
Residents: (by age groi
0-1
1-4
4-7
7-11
11-15
15-18
18-70
Total lifetime risk:
(for carcinogens)
Future Workers:
Inhalation
Ingestion
Dermal
?₯*««+ 1 14 &**+ -{MA -vtcvlr.
Total. .lire time nsjc:
(for carcinogens)
SELINE RISKS FOR THE
HAZARD INDEX
IP)
0.83
1.21
1.35
0.70
0.57
0.50
0.51
( chronic/subchronic)
43.9/43.8
2.42/2.38
4.49/4.37
ABEX SITE
CANCER RISK
1.20 X 10"8
1.29 X 10'*
3.34 X 10'6
2.36 X 10*6
1.59 X 10*
1.35 X 10'6
2.09 X 10'5
3.0 X 10*5
4.10 X 10'4
1.46 X 10'*
3.41 X 10'*
80*7 v i n~^
y i x xu
FUTURE RISKS ASSOCIATED WITH SUBSURFACE SOIL
The risk assessment that was performed for the Abex Site
does not specifically address the issue of human health risks
that may exist if contaminated subsurface soil is brought to the
surface by future activity. The risk assessment only briefly
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discusses this subject in conjunction with current and future
land use and states that highly contaminated subsurface soils
could be brought to the surface if large scale development
occurs.
In addition to large scale development, EPA and VDWM have
considered other possible mechanisms for exposure to subsurface
soils either directly or by the transport of these soils to the
surface. Routine activities by property owners or their children
that could result in direct contact with subsurface soils
include, but are not limited to: gardening of fruits, vegetables
and other plants; children playing in soil (e.g. digging holes,
making mudpies, etc.); and installing fence posts, decks, and
playground equipment. Construction activities that could result
in human exposure to contaminated subsurface soil and the
recontamination of surface soil include, but are not limited to,
construction of housing additions, maintenance and
addition/replacement of subsurface utilities, demolition of
existing buildings/structures, construction of new
buildings/structures, and construction of in-ground pools.
EPA and VDWM are unaware of any research or models that can
be used as a basis for estimating the potential future exposure
of residents to subsurface soil contamination. Since future
activities in the residential areas of OU1, unless restricted,
could reasonably result in either direct exposure to contaminated
subsurface soil or exposure to contaminated soil reintroduced to
the surface, EPA and VDWM believe surface and subsurface soil are
of equal concern. Since this ROD identifies the final remedial
action for contaminated soil in OU1, EPA and VDWM believe a
conservative approach to determining the extent of cleanup is
appropriate.
f
ECOLOGICAL RISK
The OU1 RI focused on the area within a 700-foot radius of
the foundry which is a predominantly urban area. A formal
ecological risk assessment that qualitatively and/or
quantitatively appraises the actual or potential effects of the
Site on plants and animals was not performed as part of this OU.
An investigation of the ecological impacts that may be associated
with this Site, particularly with regard to the Elizabeth River
and offsite environmental receptors, will be evaluated in OU2.
LEAD CLEANUP LEVELS
After completion of the baseline risk assessment at a site,
appropriate cleanup levels are considered during the feasibility
study in order to evaluate the effectiveness of the remedial
alternatives. For sites dealing with lead contamination, EPA
recommends,, as a matter of policy (OSWER Directive #9355.4-02),
that soil cleanup levels in the range of 500 to 1,000 mg/kg lead
be used to trigger a remedial action in residential areas. The
33
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use of a specific level to trigger an action has proved to be an
effective method for implementing cleanup activities. After
cleanup has been completed, confirmatory sampling is performed to
ensure that unacceptable risks identified in the baseline risk
assessment have been addressed. Since other contaminants of
concern identified at the Abex Site are found in close
association with lead, actions taken to achieve the lead cleanup
levels will also be effective in addressing unacceptable risks
from these contaminants.
VII. DESCRIPTION OF ALTERNATIVES
Engineering technologies were screened in-the FS report to
determine which ones could be applied to clean up contamination
identified at the Site. The technologies were evaluated based on
their effectiveness, cost, and implementability. Those
technologies determined to be most appropriate were then
developed into remedial alternatives. Table 8 presents the
alternatives evaluated in this ROD, their present worth cost, and
the time required for implementation. These alternatives are for
work to be performed in addition to that already performed under
the Removal Action.
COMMON ELEMENTS OF ALL ALTERNATIVES:
Except for Alternative 1, the No-Action Alternative, all of
the remedial alternatives include the following common elements:
Demolition of Former Foundry Facility Buildings
All buildings associated with the former foundry operation
would be demolished in Alternatives 2-7.1 Building debris would
be disposed of off site in an approved RCRA landfill in accordance
with RCRA Land Disposal Restrictions., Equipment maintained
within these buildings by the current property owner would have
to be removed and may require decontamination.
Solid residuals generated by any decontamination activities
would be handled in the same manner as contaminated soil. Any
contaminated soil beneath the buildings would be addressed in the
same manner as surrounding non-residential soil on the Holland
Property, the Abex Lot, and the McCready Lot.
1 This represents a change from the Proposed Plan which
indicated that building would be decontaminated. Section XI
(Documentation of Significant Changes) provides further
explanation*
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TABLE 8 - REMEDIAL ALTERNATIVES
ALTER-
NATIVE
1
2
3
4
5
6
7
DESCRIPTION
No Action
Surface soil excavation;
Off site treatment and
disposal; Capping Abex Lot,
McCready Lot, and Holland
Property ; Institutional
Controls
Surface and subsurface soil
excavation; Off site
treatment and disposal
Surface and subsurface soil
excavation; Onsite
treatment; Off site disposal
Surface and subsurface soil
excavation, Onsite
treatment; Off site
disposal, Capping Abex Lot,
McCready Lot, and Holland
Property; Institutional
Controls
Surface and subsurface soil
excavation ; Ons ite
treatment; Off site
disposal; In-situ treatment
and capping of Abex Lot,
McCready Lot, and Holland
Property, Institutional
Controls
Surface and limited
subsurface soil excavation;
Onsite treatment; Off site
disposal ; Institutional
Controls2
TOTAL COST
(Present
Worth)
0
4,888,930
37,895,000
28,891,243
22,074,430
23,654,430
16,169,450
TIME TO
CONSTRUCT
(Weeks)
0
12
57
55
44
45
40
2 The Proposed Plan did not identify institutional controls as
part of Alternative 7. Upon further consideration, EPA and VDWM
have determined that institutional controls would be necessary for
Alternative 7 to be protective of human health and the environment.
Section XL (Documentaion of Significant Changes) provides further
discussion.
35
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Soil Excavation. Offsite Disposal, and Temporary Relocation
Soil excavation and offsite soil disposal is required to
various extents under all of the alternatives. TCLP testing
would be conducted to determine whether excavated soil is a RCRA
characteristic hazardous waste. Soil which is determined to be a
RCRA hazardous waste would be treated prior to land disposal.
Soil which is not a RCRA hazardous waste may still require
treatment prior to disposal in a solid waste facility within
Virginia or another state. Conventional earth moving equipment
would be used to excavate and load the contaminated soil.
Contaminated soil beneath homes and residential units may be
removed using vacuum-type equipment. Dust suppression measures
would be used to ensure that unacceptable releases on air-borne
contamination do not occur. All excavated areas would be
backfilled with clean fill and revegetated to achieve former
conditions, to the extent practicable. Temporary relocation
would be provided to residents while excavation is occurring
around or beneath their homes or residential units.
Soil Treatment By Stabilization and/or Solidification
Where treatment is included, the treatment would be
stabilization by mixing excavated soil and waste materials from
the Site that exhibit toxicity using the TCLP test with
chemicals/reagents. The mixing would be contained in above-
ground equipment onsite to create a final product that
encapsulates and immobilizes lead and other metals. Specific
chemicals to be used in the process would be determined in a
treatability study during the Remedial Design phase of the
project. Treated material would be tested using TCLP to ensure
it no longer exhibits toxic characteristics.
Discharge of Contaminated Water
Discharge of decontamination water and any other water
generated during remedial activities will meet Virginia Pollution
Discharge Elimination System (VPDES) requirements developed
pursuant to the Federal Clean Water Act, 31 U.S.C. §§1251 et
sea.. and the Virginia State Water Control Law, Code of Virginia
§§ 62.1-44.2 et sea.
Air Emissions Monitoring Purina Remedial Activities
Air will be monitored for both dust and lead levels during
the remedial activities to protect the health of onsite workers
and the community. Sampling of the interior of homes in the
vicinity of excavation will also be performed before, during, and
after excavation to assure that there is no significant release
of contaminated dust into homes during the remedial activity.
'Air will be monitored to ensure that the National Emission
Standards for Hazardous Air Pollutants (NESHAPs) developed under
the Federal Clean Air Act, 40 C.F.R. § 50.12 and 50.6, and the
Virginia Regulations for the Control and Abatement of Air
Pollution (VRCAAP), VR 0401-0101, are not exceeded.
36
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Transportation. Storage, Treatment and Disposal of Soil and
Debris in Conformance with State Requirements
In all cases, transportation, storage, treatment and
disposal of soil and debris will be in compliance with applicable
with Virginia Hazardous Waste Management Regulations (VHWMR) or
Virginia Solid Waste Management Regulations.
DESCRIPTION OF EACH ALTERNATIVE:
A description and the estimated cost of each alternative are
summarized below. Present Worth includes an estimate of
operation and maintenance (O & M) costs over a thirty (30) year
period.
Alternative l: No Action
Pursuant to the National Contingency Plan (NCP), 40 C.F.R.
Section 300.430(e)(6), the "no action" alternative is considered
to provide a baseline for comparison to other remedial
alternatives. Under this alternative, no action beyond the
removal actions would be performed.
Surface soil (0-12" in depth) with lead levels exceeding 500
mg/kg would remain at the drug rehabilitation center property and
the vacant lots. Subsurface soil (> 12" in depth) with lead
levels exceeding 500 mg/kg would remain in the Washington Park
Housing Project, the Effingham Playground, the Effingham
residential area, and the Seventh Street row homes. Subsurface
soil exceeding 1,000 mg/kg lead would remain at the Abex and
McCready Lots, the Holland Property, the drug rehabilitation
center property, and in the vacant lots. Certain areas of lead
contamination, including the Abex and McCready lots, and areas of
the Holland Property, are currently capped and fenced, minimizing
exposure to underlying lead at this time. However, these caps
would not be permanently maintained under this alternative. This
action would not reduce the risks to the public health and the
environment outlined in Section VI above.
Since no action is proposed, there are no costs.
Alternative 2: Surface Soil Excavation, Offsite Treatment/
Disposal, Capping, and Institutional Controls
Under this alternative, remaining surface soil (0-12" in
depth) exceeding 500 mg/kg lead, except soil currently capped,
would be excavated. Areas of excavation would include the drug
rehabilitation center property, the Effingham Residential area
and the vacant lots. The excavated soils would be transported in
accordance with RCRA requirements to an approved RCRA Treatment
Facility. The soils would be treated at the offsite facility,
tested using TCLP to ensure RCRA Land Disposal Restriction
37
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requirements are met, and disposed of in an approved RCRA
Subtitle D landfill. Excavated areas would be backfilled with
clean soil/ graded, and revegetated. Institutional land use
controls (e.g., deed restrictions) restricting activity below one
foot in depth would be required on all properties where lead
concentrations in subsurface soil exceed 500 mg/kg in residential
ares and 1,000 mg/kg in non-residential areas.
Existing caps (i.e., pavement) on the Abex Lot, McCready Lot
and the Holland Property would be permanently maintained under
this alternative. Institutional controls would be required to
control future exposure to the capped soils on these lots.
A CERCLA five-year review would be required under this
alternative because hazardous substances would be left onsite.
This alternative is designated as Alternative II, Case 1, in the
FS and additional information developed in response to public
comments.
Estimated Capital Cost: $ 4,865,430
Estimated 0 & M Cost: $ 23,500
Present Worth: $ 4,888,930
Time to Construct: 12 weeks
(Note: O & H costs are presented for a 30-year period. Since
maintenance on capped areas would need to continue beyond 30
years, O 4 M costs would actually exceed this amount.)
Alternative 3: Surface and subsurface soil Excavation/ Offsit*
Treatment/Disposal
Surface and subsurface soil exceeding 500 mg/kg lead in
residential areas, including contaminated soil adjacent to home
foundations and beneath homes3, would be excavated to the depth
of the water table. Since the water table in the project area
fluctuates and has been observed at depths from three to six feet
below the surface, excavation would occur during the period when
the water table is at the seasonally low elevation, to the extent
practicable. Geotechnical investigations would be performed
during the Remedial Design to determine appropriate construction
techniques to be used to maintain the structural integrity of the
homes during excavation. Temporary relocation would be provided
to residents while excavation is occurring around or beneath
their homes or residential units.
In non-residential areas, surface soil (0-12" in depth)
exceeding 500 mg/kg lead and subsurface soil (>12" in depth)
3 This clarification oh the extent of excavation was not
included in the Proposed Plan. Section XI (Documentation of
Significant Changes) provides further discussion.
38
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exceeding 1,000 mg/kg* lead would be excavated to the depth of
the water table. To the extent practicable, excavation would
occur during the period when the water table is at the seasonally
low level.
All excavated areas would be backfilled with clean soil.
Formerly vegetated areas would be graded and reestablished to
orignial conditions, to the extent practicable.
The excavated soils would be transported in accordance with
RCRA requirements to an approved RCRA Treatment Facility. The
soils would be treated at the offsite facility, tested using TCLP
to ensure RCRA Land Disposal Restriction requirements are met,
and disposed of in an approved RCRA Subtitle D landfill.
Prior to the excavation of contaminated soil on the Abex
Lot, the McCready Lot, and the Holland Property, existing asphalt
and concrete would be removed and disposed as construction and
demolition debris. This alternative is designated as Alternative
II, Case 2, in the FS and additional information developed in
response to public comments.
Estimated Capital Cost: $ 37,895,000
Estimated O & M Cost: 0
Present Worth: $ 37,895,000
Time to Construct: 57 weeks
Alternative 4: Surface and Subsurface Soil Excavation, onsite
Treatment, Offsite Disposal
Under this alternative, contaminated surface and subsurface
soil in residential and non-residential areas would be excavated
as described under Alternative 3.
Excavated soil and waste materials would be tested using
TCLP to determine if it exhibits toxicity. Excavated soil and
waste materials not exhibiting toxicity would be transported and
disposed offsite in an approved RCRA Subtitle D landfill.
Excavated soil and waste materials exhibiting toxicity using TCLP
would be treated onsite using a stabilization process. Treated
soil and waste materials would be retested using TCLP to ensure
that it does not exhibit unaccepatble toxicity and meets RCRA
Land Disposal Restriction requirements. Treated soil and waste
materials not exhibiting toxicity would be transported in
accordance with RCRA requirements to an approved RCRA Subtitle D
landfill.
4 The Proposed Plan indicated that subsurface soil in non-
residential areas exceeding 500 mg/kg would be excavated, the same
as in residential areas. Upon further consideration, EPA and VDWM
have determined that 1,000 mg/kg is the appropriate cleanup level
for subsurface soil in non-residential areas. Section XI
(Documentation of Significant Changes) provides further discussion.
39
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Prior to excavation of contaminated soil on the Abex Lot,
the McCready Lot, and the Holland Property, existing asphalt and
concrete would be removed and disposed of as construction and
demolition debris. This alternative is based on Alternative III
Case 2 in the FS and additional information developed in response
to public comments.
Estimated Capital Cost: $28,891,243
Estimated O & M Cost: 0
Present Worth: $28,891,243
Time to Construct: 55 weeks
Alternative 5: surface and Subsurface Soil Excavation/ Onsite
Treatment/ Offsite Disposal, Capping,
Institutional controls
Under this alternative, contaminated surface and subsurface
soil in residential and non-residential areas would be excavated,
treated, and disposed of as described under Alternative 4, with
the exception of the Holland Property, the Abex Lot, and the
McCready Lot, which would be permanently capped with asphalt in
accordance with RCRA Subtitle C requirements.
Operation and maintenance, institutional land use controls,
and groundwater monitoring in accordance with RCRA requirements,
would be necessary for areas that have been capped. A CERCLA
five-year review would be required under this alternative because
this remedy will leave hazardous substances on Site. This
alternative is identified as Alternative V, Case 2 in the FS and
additional information developed in response to public comments.
Estimated Capital Cost: $ 22,074,430
Estimated O & M Cost: $ 23,500
Present Worth: $ 22,097,930
Time to Construct: 44 weeks
(Note: O & M costs are presented for a 30-year period. Since
maintenance on capped areas would need to continue beyond 30
years, 0 & M costs would actually exceed this amount.)
Alternative 6s Surface and subsurface Soil Excavation, Onsite and
In-Situ Treatment, Offsite Disposal, Capping,
Institutional Controls
Under this alternative, contaminated surface and subsurface
soil in residential and non-residential areas would be excavated
treated, and disposed of as described under Alternative 4, with
the exception of the Holland Property, the Abex Lot, and the
McCready Lot, which would be treated in-situ (in place) to
immobilize the lead in the soil and waste material.
The in-situ treatment process utilizes augers and mixing
40
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p^Jdles to facilitate the injection and mixing of stabilizing
agents into subsurface soils. Upon completion of this process,
lead within the soil and waste material is expected to be
stabilized. Pilot-scale treatability studies would be required
to confirm the effectiveness of the in-situ treatment system.
Prior to the in-situ treatment, existing asphalt and
concrete on the Abex Lot, McCready Lot and Holland Property would
be removed and disposed of as construction and demolition debris.
After the treatment is complete, these areas would capped in
accordance with RCRA requirements. Operation and maintenance,
institutional land use controls, and groundwater monitoring in
accordance with RCRA requirements, would be necessary for areas
that have been treated in-situ and capped. A CERCLA five-year
review would be required. This alternative is identified as
Alternative VII, Case 2, in the FS and additional information
developed in response to public comments.
Estimated Capital Cost: $ 23,654,430
Estimated O & M Cost: $ 23,500
Present Worth: $ 23,677,930
Time to Construct: 45 weeks
(Note: O & M costs are presented for a 30-year period. Since
maintenance on capped areas would need to continue beyond 30
years, O & M costs would actually exceed this amount.)
Alternative 7: Surface and Limited Subsurface soil Excavation,
Onsite Treatment, offsite Disposal, Institutional
Controls
Under this alternative, soil exceeding 500 mg/kg lead would
be excavated from the surface to a depth of two feet. Subsurface
soils below two feet with lead levels above 5,000 mg/kg would be
excavated to the depth of the water table. Soil with lead levels
between 500 and 5,000 mg/kg lead would remain below a. depth of
two feet. All excavated soil would be handled as described under
Alternative 4.
Institutional land use controls preventing any disturbance
of soil below two feet would be required in areas where lead
concentrations in subsurface soil exceed 500 mg/kg5. These
controls would be necessary to prevent exposure to contaminated
subsurface soil left in place and to ensure that surface soils
are not recontaminated as a result of future construction
activities. Activities that could be restricted to prevent
5 Institutional controls were not included in Alternative 7 in
the Proposed Plan. Upon further consideration, EPA and VDWM have
determined that institutional controls would be necessary for
Alternative 7 to be protective of human health and the environment.
Section XI (Documentation of Significant Changes) provides further
discussion.
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*
recontamination of surface soil include, but are not limited to,
construction of housing additions, maintenance,
addition/ replacement of subsurface utilities, demolition of
exiting buildings/ structures , construction of new
buildings/ structures and construction of in-ground pools.
A CERCLA five-year review would be required under this
alternative because this remedy will leave hazardous substances
on Site.
Estimated Capital Cost: $ 16,169,450
Estimated O & M Cost: 0
Present Worth: $ 16,169,450
Time to Construct: 40 weeks
VIII. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
EPA has developed a process to analyze remedial alternatives
based on the statutory requirements of Section 121 of CERCLA, 42
U.S.C. §9621, and site-specific experience gained in the
Superfund program. This process uses nine criteria as set forth
in the NCP, 40 C.F.R. Section 300.430(e) (9) (iii) , which encompass
statutory requirements and technical, cost, and in
stitutional considerations that EPA has determined are
appropriate for a thorough evaluation. The nine criteria can be
categorized into three groups: threshold criteria, primary
balancing criteria, and modifying criteria. Brief descriptions
of each of these criteria by category are presented below.
THRESHOLD CRITERIA: (relates to statutory requirements that each
alternative must satisfy in order to be
eligible for selection)
(1) Overall Protection of HM?^ Health and the Environment:
Evaluation of the ability of each alternative to provide
adequate protection of human health and the environment in
the long and short-term; description of how risks posed
through each exposure pathway are eliminated, reduced, or
controlled through treatment, engineering controls, or
institutional controls.
(2) Compliance with Applicable or Relevant and Appropriate
Requirements ( ARARsi ;
Evaluation of the ability of each alternative to meet all
ARARs of Federal and State environmental laws and/or
justification for invoking a waiver; assessment of the
ability of each alternative to comply with advisories,
criteria, and guidance that EPA and VDWM have agreed to
follow.
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PRIMARY BALANCING CRITERIA: (technical criteria upon which the
detailed analysis is primarily
based)
(3) Long-term Effectiveness and Permanence;
Evaluation of expected residual risk and the ability of each
remedy to maintain reliable protection of human health and
the environment over time after cleanup goals have been met.
(4) Reduction of Toxicitv. Mobility, or- Volume through
Treatment *
Evaluation of the statutory preference for selecting
remedial actions that employ treatment technologies that
permanently and significantly reduce the toxicity, mobility,
or volume of hazardous substances.
(5) Short-term Effectiveness:
Evaluation of the period of time needed to achieve
protection and any adverse impacts on human health and the
environment that may be posed during the construction and
implementation period, until cleanup goals are achieved.
(6) Implementability;
Evaluation of the technical and administrative feasibility
of each alternative, including the availability of materials
and services.
(7) Cost;
Estimation of capital, O & M, and net present worth costs
for each alternative.
MODIFYING CRITERIA: (criteria considered throughout the
development of the preferred remedial
alternative and formally assessed after the
public comment period, which may modify to
preferred alternative)
(8) State/Support Acrencv Acceptance;
Assessment of technical and administrative issues and
concerns that the State may have regarding each alternative.
(9) community Acceptance;
Assessment of issues and concerns the public may have
regarding each alternative based on a .review of public
comments received on the Administrative Record and the
Proposed Plan.
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The alternatives were evaluated and compared in the FS
and/or the Proposed Plan based on these nine criteria. This
section summarizes EPA's comparison of alternatives based on the
previous analyses with consideration of certain clarifications
and modifications to some of the alternatives resulting from
input received during the public comment process. Table 9
provides an overview of the comparison of alternatives.
Overall Protection of Human Health and the Environment
Although surface soil (0-12" in depth) contamination in the
Washington Park Housing Project and the Effingham Playground has
been addressed under the 1992 removal action, lead levels in the
surface soil in the Effingham residential area presently exceed
the residential health-based cleanup level of 500 mg/kg; surface
soil on the Holland Property and in the vacant lots also exceeds
500 mg/kg lead; subsurface soil (> 12" in depth) in the
residential areas including the Washington Park Housing Project,
the Effingham residential area, and the Seventh Street row homes,
exceeds the health-based cleanup level of 500 mg/kg; subsurface
soil in the non-residential areas including the Holland Property,
the Abex Lot, the McCready Lot, the drug rehabilitation center,
and the vacant lots exceed 1,000 mg/kg lead. Alternative 1 (No
Action) would not prevent current and/or future exposure to lead
contaminated soil at the Abex Site and is not protective of human
health. Therefore, Alternative 1 will not be considered further
as a remedial alternative.
Alternative 2 provides a remedy for surface soil (0-12" in
depth) within OU1 that exceeds 500 mg/kg lead by excavating and
removing these soils. However, Alternative 2 does not excavate
and remove subsurface soil (> 12" in depth) within OU1 with lead
levels greater than 500 mg/kg. Exposure to subsurface soil
exceeding 500 mg/kg lead in residential areas or 1,000 mg/kg lead
in non-residential areas either directly or after contaminated
soil has been reintroduced to the surf ace over time would result
in an unacceptable human health risk. Routine activities by
property owners or their children that could result in direct
contact with subsurface soil include, but are not limited to,
gardening of fruits, vegetables and other plants, children
playing in soil (e.g. digging holes, making mudpies, etc.), and
installing fence posts, decks, and playground equipment.
Construction activities that could result in human exposure to
contaminated subsurface soil and the recentamination of surface
soil include, but are not limited to, construction of housing
additions, maintenance and addition/replacement of subsurface
utilities, demolition of existing buildings/structures,
construction of new buildings/structures, and construction of in-
ground pools.
Alternative 2 includes capping and institutional controls to
control human exposure to soil exceeding 500 mg/kg during routine
activities and construction activities. EPA and VDWM do not
support the use of restrictions on residential property as a
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method to achieve protection of human health and the environment
unless no other feasible alternatives are present.
Both Alternatives 3 and 4 would remove surface and
subsurface soil above the water table in residential and non-
residential areas to health-based cleanup levels. In residential
areas, surface and subsurface soil with lead exceeding 500 mg/kg
lead above the water table would be removed. In the non-
residential areas, surface soil above 500 mg/kg lead and
subsurface soil above 1,000 mg/kg lead would be removed to the
depth of the water table. The Abex Lot is the only area where
subsurface soil contamination above the cleanup level is expected
to occur below the water table. The Abex Lot is zoned for
commercial and/or light industrial use. Future activity is not
expected to extend into the water table and quantity of soil
exceeding 1,000 mg/kg lead below the water table is expected to
be minimal. Alternatives 3 and 4 are both considered fully
protective of human health and the environment.
Alternatives 5 and 6 would remove contaminated surface and
subsurface soil in residential and non-residential areas within
OUl as described above for Alternatives 3 and 4, with the
exception of soil within the Holland Property, the Abex Lot, and
the McCready Lot. These areas would be permanently capped with
asphalt under Alternative 5, and treated in-situ and then capped
with asphalt in Alternative 6. Institutional controls would be
required to assure permanent maintenance of the asphalt caps
under both alternatives. Alternatives 5 and 6 are both
considered protective of human health and the environment.
Alternative 7 would remove soil within OUl exceeding 500
mg/kg lead between the surface and a depth of two feet. This
removal would minimize unacceptable health risks associated with
exposure to shallow soil during routine activities including, but
not limited to, gardening of fruits, vegetables and other plants,
children playing in soil (e.g. digging holes, making mudpies,
etc.), and installing fence posts, decks, and playground
equipment (assuming these activities do not extend beyond two
feet in depth). However, under this alternative, lead levels
between 500 mg/kg and 5,000 mg/kg would remain in soil below two
feet in depth. As discussed in Alternative 2, construction
activities could result in human exposure to contaminated
subsurface soil and the recontamination of surface soil.
Institutional controls would be required to restrict construction
activities including, but not limited to, construction of housing
additions, maintenance and addition/replacement of subsurface
utilities, demolition of existing buildings/structures,
construction of new buildings/structures, and construction of in-
ground pools. As stated in Alternative 2, EPA and VDWH do not
support the use of restrictions on residential property as a
'method to achieve protection of human health and the environment
unless no other feasible alternatives are present.
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Compliance with Applicable or Relevant and Appropriate
Requirements (ARARs)
The ARARs associated with Alternatives 2-7 are the sane.
Under Alternatives 2, 5, and 7, however, some soil left in place
may be a RCRA Characteristic Hazardous Waste (O008) due to high
levels of leachable lead. In the event that such soil is
excavated during some future activity, this soil would need to be
treated and disposed of in accordance with RCRA Land Disposal
Restrictions.
All alternatives would be in compliance with existing
Federal and State ARARs.
Long-tern Effectiveness and Permanence
Long-term effectiveness and permanence refers to expected
residual risk and the ability of a remedy to maintain reliable
protection of human health and the environment over time after
cleanup levels have been met.
Alternative 2 would leave subsurface soil (> 12" in depth)
contaminated with lead levels of up to 50,000 mg/kg in place and
covered with soil and grass or asphalt within OU1, thereby
resulting in the potential for a substantial residual risk.
Alternatives 3 and 4 provide minimal residual risk and,
therefore, a high degree of long-term effectiveness since surface
and subsurface soil that exceed 500 and 1,000 mg/kg lead in
residential and non-residential areas of OU1, respectively, are
excavated, treated as required, and disposed of off site in an
approved RCRA landfill.
Alternatives 5, 6, and 7 all leave contaminated soils and/or
waste material in place, thereby allowing for potential residual
risk. Alternatives 5 would leave soil and waste material
contaminated with lead up to 58,000 mg/kg beneath asphalt caps on
the Holland Property, the Abex Lot, and the McCready Lot.
Alternative 6 would also leave contaminated soil and waste
material in place, however, in-situ treatment would take place
prior to capping and, therefore, reduce the potential residual
risk. Alternative 7 would leave soil containing 500 to 5,000
m9/fcg lead in place below two feet in depth within residential
and non-residential areas. As with Alternative 2, Alternative 7
would result in the potential for a substantial residual risk at
the Site.
Reduction of Toxicity, Mobility, or Volume Through Treatment
Lead, the primary contaminant of concern at the Site, is a
metallic element that cannot be destroyed to reduce its toxicity.
Therefore/ remedies addressing lead contamination in soil
generally require either removal and/or stabilization by
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immobilizing the lead within the soil structure, thereby reducing
the mobility of the contaminant. Stabilization, however, results
in an increase in the volume of material to be addressed and will
not reduce the toxicity of the lead.
Under Alternative 2, only surface soil (0-12" in depth)
within OU1 would be excavated and treated as appropriate (i.e.,
in accordance with RCRA Land Disposal Restriction requirements).
Contaminated soil below this level would remain in place.
Contaminated soil and waste material on the Holland Property, the
Abex Lot, and McCready Lot would remain in place and be in
accordance with RCRA requirements. This alternative, therefore,
would not significantly reduce the mobility and volume of lead
through treatment.
Under Alternatives 3 and 4, surface and subsurface soil
above the water table within OU1 that is contaminated above
health-based cleanup levels would be excavated and treated, as
appropriate, to reduce the mobility of lead in the soil. In any
case where the soil is treated, the volume of the lead-
contaminated soil will increase due to the addition of
stabilizing agents designed to reduce lead mobility.
Under Alternative 5, contaminated surface and subsurface
soil above the water table within OU1 would be excavated and
treated, as appropriate, to reduce the mobility of lead in the
soil, with the exception of contaminated soil and waste material
within the Holland Property, the Abex Lot, and the McCready Lot.
These areas would not be treated, but would be contained with one
foot of asphalt. As such, Alternative 5 would fail to treat the
primary sources of lead contamination at the Site.
Alternative 6 is the same as Alternative 5, except that
contaminated soil and waste material on the Holland Property, the
Abex Lot, and the McCready Lot would be treated in-situ before
capping. While in-situ treatment may significantly reduce the
mobility of lead, treatability studies would need to be performed
during the Remedial Design to determine the extent of the
reduction in mobility that can be achieved.
Alternative 7 would excavate and treat, as appropriate,
surface and subsurface soil within OU1 that exceeds 500 mg/kg
lead within two feet of the ground surface, as well as soil
exceeding 5,000 mg/kg between two feet in depth and the water
table. Under Alternative 7, soil between 500 and 5,000 mg/kg
lead within residential areas would remain in place below two
feet in depth. Therefore, Alternative 7 would not reduce the
mobility of lead to the extent accomplished under Alternatives 3
and 4, and perhaps under Alternative 6.
P
Short-term Effectiveness
The primary short-term effects associated with each
alternative are possible exposure to contaminated dust generated
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during excavation, and exposure to physical safety hazards that
exist around heavy equipment. Air-borne dust containing elevated
lead levels could be generated during soil excavation required in
Alternatives 2-7. The extent of soil excavation is highest
under Alternatives 3 and 4, and lowest under Alternative 2.
Additional dust could be generated during soil handling and
operation of treatment units onsite, particularly under
Alternatives 4 and 7. However, measures would be taken to
control dust during implementation of the various alternatives.
These measures would be detailed in the Remedial Action Work Plan
and the associated Health and Safety Plan which must be prepared
and approved by EPA and VDWM prior to initiation of construction.
Measures to be performed would include (1) dust suppression
during excavation, handling, and treatment activities, (2)
sampling the interior of homes for contaminated dust before,
during, and after remedial activities to ensure dust suppression
has been effectively implemented, and (3) air monitoring for both
lead and dust before and during remedial activity.
Alternatives 3-7 would require temporary relocation of
residents during excavation of contaminated surface and
subsurface soil around or beneath their home or residential unit.
This action is being taken to minimize the physical safety
hazards associated with heavy equipment operating in close
proximity to residential property. Details on the extent of
excavation required for each home or residential unit and the
arrangements for temporary relocation would be discussed with
impacted residents during the Remedial Design process.
Alternatives 4-7 require onsite treatment of excavated
soils. The Remedial Action Work Plan and Health and Safety Plan
to be developed would detail measures to be taken to secure the
area where soil is stockpiled and treated to prevent air or
water-borne releases of contaminated soil and to prevent access
by local children.
Implementability
Alternatives 3, 4, 5, and 6 require extensive excavation of
contaminated surface and subsurface soil including contaminated
soil that may exist adjacent to foundations and/or beneath homes
or residential units. Due to the unstable nature of soil or fill
material around or under many of the impacted residences and the
proximity of the water table to the ground surface (estimated at
3 to 6 feet), strict engineering practices would need to be
followed to prevent damage to the homes during excavation.
Further geotechnical investigation would be required as part of
the Remedial Design to determine appropriate construction
techniques to be used to maintain the structural integrity of
'each home or residential unit requiring excavation. While
additional costs would be incurred by implementing the necessary
engineering controls, current engineering technology can be
employed to safely remove contaminated soil around and beneath
impacted residences.
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In the case of Alternatives 4, 5, 6, and 7, implementation
of onsite treatment will require careful planning and additional
construction activities. In each case, treatability studies will
be necessary to determine the appropriate mixture of reagents
needed to effectively immobilize the lead in the soil. The
implementation of these alternatives will require significantly
more activity onsite than Alternatives 2 and 3, where treatment
would be performed offsite at an RCRA-permitted facility.
Alternative 6 includes in-situ treatment of the Holland
Property, the Abex Lot, and the McCready Lot, as well as
treatment of excavated soil from other areas of the Site in an
above-ground onsite treatment unit. The use of two separate
onsite treatment units may further increase the time necessary to
complete the remediation. Extensive pilot-scale treatment
studies would be necessary to confirm the effectiveness of the
in-situ treatment system. As a result, Alternative 6 would
likely require a significantly longer time to complete the
Remedial Design than the other alternatives.
As discussed under the criteria for Overall Protection of
Human Health and the Environment and Long-term Effectiveness and
Permanence, Alternatives 2, 5, 6, and 7 require effective
implementation of institutional controls to fully satisfy these
criteria. Of these alternatives, Alternative 2 relies most
heavily on the use of institutional controls. All properties
with subsurface soil (> 12** in depth) that exceeds 500 mg/kg in
residential areas and 1,000 mg/kg in non-residential areas would
require restrictions to limit activities that may occur below the
one-foot depth. In terms of the residential areas, most of the
privately-owned homes in the Effingham residential area, several
of the units in the Washington Park Housing Project, and several
of the Seventh Street row homes would be subject to these
restrictions. EPA and VDWM prefer not to impose such
restrictions on residential properties unless no other feasible
alternatives are present.
Alternative 7 is second to Alternative 2 in its reliance on
institutional controls to protect human health and the
environment and to achieve long-term effectiveness. All
properties with soil below two feet in depth that contains lead
at 500 to 5,000 mg/kg in residential areas and at 1,000 to 5,000
mg/kg in non-residential areas would require restrictions to
limit activities that may occur below the two-foot depth. Again,
most of the privately-owned homes in the Effingham residential
area, several of the units in the Washington Park Housing
Project, and several of the Seventh Street row homes would be
subject to these restrictions. At the time the Proposed Plan was
issued, EPA and VDWM supported this alternative as the preferred
remedy. However, during the initial analysis of alternatives,
EPA and VDWM had not fully considered the implications of
allowing contaminated soil between 500 and 5,000 mg/kg lead to
remain below two feet. EPA and VDWM also became aware during the
public comment period that many homes in the Effingham
residential area had crawl spaces, many of which were found to be
49
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contaminated with lead at levels exceeding 500 mg/kg. Upon
further consideration, EPA and VDWM recognized that institutional
controls would be required as part of this alternative. While
restrictions would probably be required on fewer properties under
Alternative 7 than under Alternative 2, and the restrictions on
property use would be less severe, EPA and VDWM still prefer not
to impose of such restrictions on residential properties unless
no other feasible alternatives are present.
The institutional controls required under Alternatives 5 and
6 are limited to restrictions needed to ensure capped areas on
the Holland Property, the Abex Lot, and the HcCready Lot are
permanently maintained. EPA and VDWM consider these
institutional controls to be implementable.
Cost
Alternative 2 has the lowest total present worth cost at
$4,888,930. However, long-term cap maintenance and groundwater
monitoring costs would actually be higher than estimated since
these activities would need to continue well beyond the 30-year
period used for estimation purposes. Administrative costs
associated with implementing institutional controls have not been
included. In addition, this cost does not reflect the fact that
use of the Holland Property, the Abex Lot, and the McCready Lot
would be permanently restricted.
Alternative 7 is the second least costly remedy with a total
present worth of $16,169,450. As in Alternative 2, this total
does not include administrative costs that would be associated
with implementing institutional and does not reflect the impact
of restricting the future use of residential and non-residential
properties.
Alternatives 5 and 6 are similar in total resent worth cost
at $22,074,430 and $23,654,430, respectively. Jhe limitations of
these cost estimates are the same as discussed for Alternative 2.
Alternative 4 is second most costly remedy with a total
present worth of $28,891,243. Alternative 3 is the most costly
alternative with an estimated present worth of $37,895,000.
There are no annual operation and maintenance costs or
administrative costs for implementing institutional controls
associated with either of these alternatives.
State A0e«ptanc«
VDWM served as the lead agency for the Abex Site during
implementation of the RI/FS. VDWM has reviewed the remedial
'alternatives under consideration for the Abex Site and has
provided EPA with technical and administrative requirements for
the Commonwealth of Virginia. VDWM agrees with the analysis of
alternatives presented in this ROD and concurs with EPA's
selected remedy discussed below.
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Community Acceptance
During the public comment period, the community expressed a
strong desire to have a remedy that guarantees protection of
human health and the environment in a manner that does not
restrict their activities in the future. Many of the comments
EPA and VDWM received from local residents expressed the concern
that none of the alternatives being considered would restore
their community to a safe level and they, therefore, preferred to
be permanently relocated. Since EPA, in consultation with VDWM,
has determined that Alternatives 3 and 4 would achieve the desire
of local residents for a remedy that restores their community to
a safe level without restricting their future activities, EPA is
not recommending permanent relocation. EPA has included
temporary relocation in the alternatives requiring excavation of
contaminated surface and subsurface soil in residential areas.
This measure will minimize the physical safety hazards associated
with heavy equipment operating in close proximity to residential
property.
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CRITERIA:
Overall Protection of Hunan
Health and the Environment
Compliance with ARARs
Long-term Effectiveness and
Permanence
Reduction of toxlcfty,
nobility, or volume through
treatment
Short-tern Effectiveness
Inplementabtllty
Cost
State Acceptance
Communi ty Acceptance
TABLE 9 - COMPARISON OF ALTERNATIVES
ALTERNATIVE
1
Mot
Achieved6
...
2
Achieved
Achieved
Low7
Lou
High
LOM
Low
Lou
Lou
3
Achieved
Achieved
High
Moderate
Moderate
High
High
High
High
4
Achieved
Achieved
High
Moderate
Moderate
High
Moderate-
High
High
Moderate
5
Achieved
Achieved
Moderate8
Low-
Moderate
Moderate
Moderate
Moderate
LOM
Low
6
Achieved
Achieved
Moderate-
High
Moderate
Moderate
Moderate ,
Moderate
Low
Low
7
Achieved
Achieved
Low-
Moderate
Moderate
Moderate
Low
Low-
Moderate
Low
Low
6 Since Alternative 1 (Mo Action) failed to meet this threshold criteria, it was not evaluated further.
7 "Low" Indicates that significant contamination it left in place In residential and non-residential areas, and there is a high reliance on
institutional controls for long-term effectiveness.
8 "Moderate" Indicates that highly contaminated soil/waste material Is left in place in non-residential areas, and there is some dependence on
Institutional controls for long-tern effectiveness.
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Based upon consideration of the requirements of CERCLA, the
detailed analysis of the alternatives presented in the Proposed
Plan using the nine criteria, and public comments, EPA, in
consultation with VDWM, has determined that Alternative 4 is the
most appropriate remedy for the Abex Superfund Site. The major
components of the remedy and the required performance standards
are listed below. Table 10 provides a detailed cost estimate for
Alternative 4.
SOIL EXCAVATION
Performance Standards;
Soil in residential areas within OU1, including the
Washington Park Housing Project, the Effingham residential
area, the Seventh Street row homes, and .the Effingham
Playground, where lead concentrations exceed 500 mg/kg shall
be excavated; excavation shall extend to the depth of the
water table and, to the extent practicable, shall be
performed when the water table is at the seasonally low
elevation.
Contaminated soil exceeding 500 mg/kg lead around the
foundations and beneath homes and residential units within
OU1 shall be excavated; the structural integrity of each
home or residential unit shall be maintained by performing
geotechnical investigations during the Remedial Design to
determine the appropriate construction measures to be taken
during excavation.
Soil from non-residential areas within OU1, including soil
currently covered with material such as asphalt or concrete
(i.e., the Holland Property, the Abex Lot, the McCready Lot,
and the drug rehabilitation center) where lead
concentrations either exceed 500 mg/kg at the surface (0-12"
in depth) or exceed 1,000 mg/kg in the subsurface (> 12")
shall be excavated; excavation of subsurface soil shall
extend to the depth of the water table and, to the extent
practicable, shall be performed when the water table is at
the seasonally low elevation; asphalt, concrete, and other
similar material that cover soil contaminated with lead
above the cleanup levels shall be removed prior to
excavation.
Additional Components?
Residents shall be temporarily relocated while surface and
subsurface soil is excavated around and/or beneath their
particular home or residential unit; dust suppression
measures shall be used to prevent contaminated dust from
entering homes or adjacent areas; sampling of the interior
of homes shall be performed before, during, and after
excavation to ensure dust control measures have been
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effective; air monitoring for lead and dust shall be
performed in accordance .with 40 C.F.R. Part 50, Appendix G,
to ensure air emissions conform with the National Primary
and Secondary Ambient Air Quality Standards for lead, 40
C.F.R. § 50.12, and particulate matter, 40 C.F.R. § 50.6,
and for the control of fugitive dust emissions in accordance
with Virginia Air Pollution Control Board Regulations, VR
04-0101.
Erosion and sediment control measures shall be installed in
accordance with the substantive requirements of the Virginia
Erosion and Sediment Control Law, Code of Virginia § 10.1-
560 et sea.. the Virginia Erosion and Sediment Regulations,
VR 625-02-00, and the City of Portsmouth's Erosion and
Sediment Control Ordinance; an erosion and sediment control
plan shall be prepared and submitted for review.
All excavated areas shall be backfilled with clean fill;
areas vegetated prior to excavation shall be restored to
original conditions to the extent practicable.
Additional sampling and analysis of soil shall be performed
prior to excavation to determine the full extent of
contamination. Sampling and analysis shall also be
performed after excavation has been completed to confirm
that cleanup goals set forth in the performance standards
have been achieved; methods for determining that the
cleanup goals have been reached shall be finalized during
the Remedial Design and approved by EPA and VDWM based on
EPA 230/02-89-042, Methods for Evaluating the Attainment of
Cleanup Standards. Vol I.
Excavated soil and waste materials shall be temporarily
staged onsite prior to treatment and/or transportation to an
offsite disposal facility; to the extent practicable,
excavated soil and waste material shall be staged in areas
of existing contamination, preferrably on the Abex Lot, the
Holland Property, and the McCready Lot; measures such as
berms and temporary covers shall be used in areas with
staged material to ensure that there are no unacceptable air
or water-borne releases of contamination from these areas;
these measures shall be sufficient to provide protection in
the event of flooding; areas that are used to stage
excavated material shall be secured with a fence to prevent
. trespassing.
When the final areas of contamination are being addressed at
the Site, excavated soil and waste materials may need to be
staged in an area where cleanup has previously occurred. In
all instances where soil and waste materials are staged in
areas where cleanup has previously occurred or are otherwise
not contaminated above levels requiring excavation, soil and
waste material shall be staged in containers in accordance
with RCRA regulations contained in 40 C.F.R. Part 268.50;
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containers used shall be in compliance with VHWMR Section
10.8 Use and Management of Containers.
SOIL TREATMENT AND DISPOSAL
Performance Standards:
Excavated soil and waste materials shall be tested using
TCLP to determine if they exhibit toxicity as defined in 40
C.F.R. Part 261, Subpart C; contaminated soil that does not
exhibit toxicity during testing shall be disposed of offsite
at an approved RCRA Subtitle 0 landfill.
Soil and waste material that exhibits toxicity due to the
leaching of lead or other metals of concern shall be handled
as a RCRA Characteristic Waste as defined in 40 C.F.R. Part
261, Subpart C. Such material shall be treated prior to
disposal using a stabilization process that mixes the
excavated soil and waste materials with chemicals/reagents
to create a final product that encapsulates and immobilizes
the lead and other metals; specific chemicals to be used in
the process shall be determined in a treatability study
during the Remedial Design phase of this project; mixing
shall be contained in above-ground equipment onsite in
accordance with VHWMR Section 10.9, Tanks.
Treated material shall be tested using TCLP to ensure it no
longer exhibits toxic characteristics; treated material that
continues to exhibit toxicity shall either be subject to
additional treatment to further reduce toxicity, or disposed
of offsite in an approved RCRA Subtitle C landfill if RCRA
Land Disposal Restriction requirements have been met;
treated material that no longer exhibits toxicity using TCLP
shall be disposed of offsite in an approved RCRA Subtitle D
landfill; if a disposal facility in Virginia is used, the
treated waste is considered a "Special Waste" under Part
VIII of VSWMR and specific approval from VDWM's Director
shall be obtained prior to disposal.
Additional Components;
Air monitoring for lead and dust shall be performed in
accordance with 40 C.F.R. Part 50, Appendix G, to ensure air
emissions conform with the National Primary and Secondary
Ambient Air Quality Standards for lead, 40 C.F.R. § 50.12,
and particulate matter, 40 C.F.R. S 50.6, and for the
control of fugitive dust emissions in accordance with
Virginia Air Pollution Control Board Regulations, VR 04-
0101.
The onsite treatment unit shall be housed in a temporary
structure to minimize exposure to the elements" and the
opportunity for air or water-borne releases.
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Treated material shall be staged onsite in accordance with
the sane requirements described above for staging untreated
excavated soil and waste materials.
Any transportation of hazardous waste from the Site shall be
performed in accordance with VHWMR Part VII, Regulations
Applicable to Transporters of Hazardous Waste, and RCRA
requirments as defined in 40 C.F.R. Parts 262 and 263, and
49 C.F.R. Parts 107,and 171 - 179; any local roads damaged
by the increased truck traffic associated with the remedial
action shall be repaired in a timely manner following the
conclusion of the onsite activity.
Any offsite discharge of water generated from the onsite
soil treatment system or from site decontamination
activities shall be in compliance with the Virginia Surface
Water Standards and the Virginia Pollution Discharge
Elimination System (VPDES) requirements; any disposal of
wastewater at a local Publicly-Owned Treatment Works (POTW)
shall be in compliance with the POTW's VPDES permit and
pretreatment standards or requirements.
Any treatment and/or storage units used during the remedial
action (i.e., tanks or containers for storage or
treatment)that are regulated under VHWHR/RCRA requirements
shall meet the closure and post-closure care requirements of
VHWMR Section 9.6.
BUILDING DEMOLITION
Performance Standard;
All existing structures on the Holland Property associated
with the former foundry operations shall be demolished;
debris exhibiting toxicity using TCLP shall be
decontaminated in accordance with RCRA Land Disposal
Restriction requirements effective at the time when
demolition occurs; debris shall be disposed of in an
approved RCRA landfill.
Additional Components;
Equipment stored by the current owner shall be sampled to
determine if is contaminated; if analytical results find
contamination, the equipment shall be decontaminated prior
to removal from the Site.
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TABLE 10 - ESTIMATED COSTS OF SELECTED REMEDY
Action
Soil Excavation (not
including soil beneath
homes)
Soil Removal
Beneath Homes
Soil Treatment
Soil Disposal
Asphalt Disposal
Backfilling
Structure
Stabilization
Utility Replacement:
Water Lines
Sever Lines
Air and Residence
Monitoring
Temporary Relocation
Building Demolition
Debris Decontamination
Debris Disposal
SUBTOTAL
Engineering and
Management 10%
Sampling and Testing
@ 5%
Contingency § 25%
Construction
Monitoring e 10%
TOTAL COST
Unit cost
$62.50/ton
$21,333
per home
$90.00/ton
$84.00/ton
$65.00/ton
$15.00/ton
$29,000
each
$37.33/LF
$11.60/LF
$2000
per family
$0.2 I/ ft2
$0.35/ft2
$100/ton
Quantity
59,542 tons
30 homes
59,542 tons
74,436 tons
403 tons
74,407 tons
30
5875 feet
5875 feet
62 families
875,000 ft2
105,000 ft2
4,453 tons
Cost
$ 3,721,375
$ 639,990
$ 5,358,780
$ 6,252,624
$ 26,195
$ 1,116,105
$ 870,000
$ 219,310
$ 68,150
$ 198,500
$ 124,000
$ 183,750
$ 36,750
$ 445,300
$19,260,829
$ 1,926,083
$ 963,041
$ 4,815,207
$ 1,926,083
$28,891,243
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X. STATUTORY DETERMINATIONS
EPA's primary responsibility at Superfund sites is to
undertake remedial actions that achieve adequate protection of
human health and the environment. In addition, Section 121 of
CERCLA, 42 U.S.C § 9621, establishes several other statutory
requirements and preferences. Under this Section, the selected
remedy for the Site, when completed, must comply with ARARs
established under Federal and State laws unless a statutory
waiver is justified. The selected remedy must also be cost-
effective and utilize permanent solutions and alternative
treatment technologies or resource recovery technologies to the
maximum extent practicable. Finally, CERCLA includes a
preference for remedies that employ treatment that permanently
and significantly reduce the volume, toxicity or mobility of
contamination as their principle element. This section discusses
how the selected remedy meets these statutory requirements.
Protection of Human Health and the Environment
The baseline risk assessment for the Abex Site determined
that the Site currently presents unacceptable risks to residents
through exposure to contaminated soil and would pose unacceptable
risks to workers exposed to contamination in the former foundry
building. The risk assessment, through use of the UBK Model,
indicates that average lead concentrations exceeding 400 mg/kg
present an unacceptable risk to children. Average lead
concentrations in surface soil exceed this level in the Effingham
residential area, on the Holland Property, and in the vacant
lots. Average lead concentrations also exceed 400 mg/kg in
subsurface soil in the Washington Park Housing Project, the
Effingham residential area, the Seventh Street row homes, the
Holland Property, the Abex Lot, the drug rehabilitation center,
and the vacant lots.
The baseline risk assessment also indicates that children
between the ages of one and seven and future workers at the
former foundry building would be exposed to unacceptable risks
associated with other noncarcinogenic contaminants of concern,
including copper, antimony, tin, zinc, nickel, cadmium, chromium,
PAHs, and PCBs. The total lifetime cancer risks associated with
the Site are 3.0 x 10"5 for residents (i.e., one additional
incident of cancer in an exposed population of 33,333) and 8.97 x
10~* for future workers at the former foundry facility (i.e., one
additional incident of cancer in an exposed population of 1,115).
Excavation, treatment, and offsite disposal of contaminated
surface and subsurface soil at the Site and demolition of the
former foundry buildings will virtually eliminate exposure to all
'contaminants of concern at the Site. By removing surface and
subsurface soil contaminated above 500 mg/kg lead in the
residential areas, EPA and VDWM expect the average lead
concentration in the soil to be in the range of 100 to 300 mg/kg.
This is.below the average soil concentration of 400 mg/kg, which
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the DBK Model estimates as the acceptable level for children.
The risks associated with the other contaminants of concern will
be within acceptable ranges as well through implementation of
this remedy.
The short-term threats associated with the selected remedy
can and will be readily controlled and no adverse cross-media
impacts are expected from the remedy.
Compliance with Applicable or Relevant and Appropriate
Requirements (ARARs) and To Be Considered Materials (TBCs)
Under Section 121(d) of CERCLA, 42 U.S.C. S 9621(d), and EPA
guidance, remedial actions at Superfund sites must attain legally
applicable or relevant and appropriate Federal and state
environmental standards, requirements, criteria, and limitations
(collectively referred to as ARARs). Applicable requirements are
those substantive environmental protection requirements,
criteria, or limitations promulgated under Federal or state law
that specifically address hazardous material found at the site,
the remedial action.to be implemented at the site, the location
of the site, or other circumstances at the site. Relevant and
appropriate requirements are those which, while not applicable to
the site, nevertheless address problems or situations
sufficiently similar to those encountered at the site that their
use is well suited to that site.
The selected remedy will comply with ARARs and To Be
Considered Materials (TBCs). The ARARs and TBCs are presented
below.
CHEMCIAL-SPECIPIC ARARS
The Resource Conservation and Recovery Act, 42 U.S.C. SS
6901 e£. seg. (40 C.F.R. Parts 261-270), the Virginia Waste
Management Act, Code of Virginia g 10.1-1400 et seg., the
Virginia Waste Management Regulations (VHWMR), VR 672-10-1,
and the Virginia Solid Waste Management Regulations (VSWMR),
VR 672-20-10 regulate the generation, transportation,
treatment, storage, and disposal of hazardous wastes.
Based on TCLP testing, some of the soil found during the RI
exhibits toxicity for lead and would be regulated as a RCRA
characteristic hazardous waste (40 C.F.R. Part 261, Subpart
C and VHWMR Part III). As a result, RCRA and VHWMR are
applicable to the treatment, transportation, and disposal of
these soils.
Clean Water Act, 31 U.S.C. SS1251 e£ seg. (National
Pollution Discharge Elimination System requirements, 40
C.F.R. Part 122), the Virginia State Water control Law, Code
of Virginia S 62.1-44.2 et seq.. the Virginia State Water
Control Board regulations, Water Quality standards, VR 680-
21-00,/the Virginia Pollutant Discharge Elimination System
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(VPDES) and Virginia Pollution Abatement (VPA) Permit
Program, VR 680-14-01, and the Virginia water Protection
Permit, VR 680-15-02 regulate any discharge of wastewater to
waters of the Commonwealth of Virginia.
National Primary and Secondary Ambient Air Quality Standards
for Lead (40 C.F.R. Part 50.12), and for Particulate Matter
(40 C.F.R. Part 50.6), the Virginia Air Pollution Control
Board, Code of Virginia § 10.1-1300 et seq.. and the
Virginia Department of Air Pollution Control regulations for
the Control and Abatement of Air Pollution, VR 120-01-01
regulate air emissions and establish permissible levels of
lead and particulate matter that can be released into the
environment.
LOCATION-SPECIFIC ARARs
Executive Order 11988, Floodplain Management, the National
Flood Insurance Act of 1968, the Flood Disaster Act of 1973,
and Procedures for Implementing the Requirements of the
Council on Environmental Quality on the National
Environmental Policy Act regulate activities that take place
in floodplains. The Site is located within a 500-year
floodplain for the South Branch, Elizabeth River.
Coastal Zone Management Act; the Coastal Management Plan for
the City of Portsmouth; and the National Oceanic and
Atmospheric Administration (NOAA) Regulations on Federal
Consistency With Approved State Coastal Zone Management
Programs regulate activities that take place in coastal
areas. The Site lies within the Coastal Management Zone of
the City of Portsmouth.
Chesapeake Bay Preservation Act, Code of Virginia S 10.1-
2100 and the Chesapeake Bay Preservation Area Designation
and Management Regulations (CBPA Regulations), VR 173-02-01
regulate activities that take place in the Chesapeake Bay
area. The City of Portsmouth Planning Department has
designated the area in which the Site lies as a Resource
Management Area of a Chesapeake Bay Preservation Area.
ACTION-SPECIFIC ARARs
Virginia Erosion and Sediment Control Law, Code of Virginia
S 10.1-560 et seq.. and the Virginia Erosion and Sediment
Control Regulations, VR 625-02-00 requires control measures
during earth-moving activities to prevent erosion and
transport of sediment in surface water runoff.
40 C.F.R. Part 50, Appendix G establishes protocols for air
monitoring.
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40 C.F.R. Part 264, Subpart I, and VHffMR Section 10.8 Use
and Management of Containers regulate the use of containers
for storing and/or treating hazardous wastes.
40 C.F.R. Part 264, Subpart J, and VHffMR Section 10.9, Tanks
regulate the use of tanks for storing and/or treating
hazardous wastes.
40 C.F.R. Parts 262 and 263, 49 C.F.R. Parts 171-179, and
VSffMR Part VII, Regulations Applicable to Transporters of
Hazardous Waste regulate transportation of hazardous wastes
in the Commonwealth of Virginia.
Virginia Solid Waste Management Regulations (VSffMR) Part
VIII, VR 672-10-1 regulates disposal of "Special Wastes" in
Commonwealth of Virginia RCRA Subtitle D solid waste
landfills. Treated soil that no longer exhibits toxic
characteristics would be a special waste.
Occupational Safety and Health Administration Act (29 C.F.R.
Parts 1910, 1926, and 1904) regulates health and safety in
the work place.
criteria/ Advisories, or Guidance TO Be Considered (TBCs):
Interim Guidance on Establishing Soil Lead Cleanup Levels at
Super-fund Sites (EPA OSffER Directive 9355.4-02) recommends
use of the UBK Model and appropriate assumptions to develop
soil cleanup levels for lead.
Methods for Evaluating the Attainment of Cleanup Standards,
Vol. I (EPA 230/02-89-042) recommends statistical methods to
confirm soil cleanup levels have been achieved.
Cost Effectiveness
EPA and VDWM considered less expensive alternatives during
the remedy selection process, however/ these alternatives did not
provide the level of protection of human health, long-term
effectivenss, reduction in mobility of contamination through
treatment, or community acceptance that was provided by the
selected remdy, Alternative 4. EPA and VDWM believe the selected
remedy will eliminate unacceptable risks to human health at the
Site at an estimated cost of $28,891,243 and, therefore, provides
an overall benefit proportionate to its costs. The selected
remedy also assures, with a much higher degree of certainty, that
the remedy will be effective in the long-term because
contaminated surface and subsurface soil in both residential and
non-residential areas within OU1 will be excavated, treated as
appropriate, and disposed of offsite.
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utilisation of Permanent solutions and Alternative Treatment
Technologies to the *t«»in^ni Extent Practicable
Section 121(b) of CERCLA, 42 U.S.C. § 9621(b), establishes a
preference for remedial actions that permanently and
significantly reduce toxicity, mobility, or volume of hazardous
substances over remedial actions which will not. EPA, in
consultation with VDWM, has determined that the selected remedy
represents the maximum extent to which permanent solutions and
treatment technologies can be utilized in a cost-effective manner
to control contamination at the Abex Site. Of those alternatives
that are protective of human health and the environment and
comply with ARARs, EPA, in consultation with VDWM, has determined
that this selected remedy, Alternative 4, provides the best
balance of tradeoffs in terms of long-term effectiveness and
permanence, reduction in toxicity, mobility, or volume through
treatment, short-term effectiveness, implementability, and cost,
while also considering the statutory preference for treatment as
a principal element, and state and community acceptance.
The selected remedy treats lead-contaminated soil that
exhibits toxicity, as determined using TCLP, thereby achieving
significant reduction of the mobility of lead in soil.
Alternatives 3 and 4 provide the most effective treatment of any
of the alternatives considered, with Alternative 4 being the most
cost effective. The selection of treatment of the contaminated
soil is consistent with program expectations that indicate that
highly toxic wastes are a priority for treatment and often
necessary to ensure the long-term effectiveness of a remedy.
Preference for Treatment as Principal Element
By treating the contaminated soil at the Site that exhibits
toxicity using TCLP, the selected remedy addresses the principal
threats posed by the Site through the use of treatment
technologies and satisfies the statutory preference for remedies
that employ treatment as a principal element.
XI. DOCUMENTATION OF SIGNIFICANT CHANGES
The Proposed Plan, released for public comment on April 28,
1992, identified Alternative 7 as the preferred alternative of
VDWM and EPA. At that time, EPA and VDWM had not fully
considered the implications of Alternative 7 with respect to
allowing contaminated soil between 500 and 5,000 mg/kg lead to
remain at depths below two feet in both residential and non-
residential areas. During the public comment period, EPA and
VDWM recognized that institutional controls would be required as
part of this alternative. All properties with soil contaminated
below two feet in depth at levels of 500 to 5,000 mg/kg in
residential areas and at 1,000 to 5,000 mg/kg in non-residential
areas would require restrictions to limit activities that may
occur below the two-foot depth. These restrictions would
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significantly impact the current residential areas. Most of the
privately-owned homes in the Effingham residential area, several
of the units in the Washington Park Housing Project, and several
of the Seventh Street row homes would be subject to these"
restrictions. EPA, in consultation with VDWM, decided to select
a remedy that includes excavation of contaminated soil below two
feet (Alternative 4) rather than one that would impose
restrictions on residential properties (Alternative 7). Section
VIII (Summary of Comparative Analysis of Alternatives) of the ROD
presents the full evaluation of the all alternatives based on the
nine criteria identified in the MCP and provides the basis for
the selection of Alternative 4.
Several additional changes and clarifications were made to
the Common Elements associated with the alternatives after
considering comments received during the public comment period.
In the Proposed Plan, the former foundry facility was to be
decontaminated. Based on comments received and further review of
the condition of the former foundry building, and several
associated structures, the ROD requires demolition.
Several residents raised questions about contamination in
crawl spaces beneath their homes during the public comment
period. Sampling performed as part of the recent removal action
confirmed that lead contamination above 500 mg/kg exists beneath
many of the homes. The ROD clarifies that excavation of
contaminated soil adjacent to foundations and beneath homes is
required as part of alternatives that include excavation of
contaminated subsurface soil.
Due to the extent of excavation that may be required around
and beneath homes and residential units, and in response to
concerns raised by many local residents, temporary relocation was
added as a Common Element for all alternatives requiring
subsurface soil excavation. Temporary relocation would be
provided to residents while excavation is occurring around and/or
beneath their home or residential unit.
A final change made to the alternatives requiring subsurface
excavation (> 12" in depth) in non-residential areas is a change
in the lead cleanup level from 500 mg/kg to 1,000 mg/kg. This
change was made: (1) to reflect the fact that nearby residents
are not expected to be exposed to subsurface soil in the non-
residential areas to the same extent they would be exposed in
residential areas and (2) to be consistent with the lead cleanup
levels used at other Superfund site for non-residential land use.
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