United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R04-93/164
September 1993
SERA Superfund
Record of Decision:
Savannah River (USDOE)
(Operable Unit 7), SC
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50272-101
REPORT DOCUMENTATION '• REPORT NO.
PAGE EPA/ROD/R04-93/164
3. Recipient1* Accession No.
4. THK «nd Subtitle
SUPERFUND RECORD OF DECISION
USDOE Savannah River (Operable Unit 7) , SC
Fifth Remedial Action
5. Report Date
09/10/93
6.
7. Authors)
8. Portormlng Organization Rapt No.
9. Performing Organization Nam* and Address
10 Project Task/Work Unit No.
11. Contract(C)orGram(G)No.
12. Sponsoring Organization Nam* and Address
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report*. Parted Covered
800/800
14.
15. Supplammtaiy Notes
PB94-964019
16. Abstract (UmH: 200 words)
The US DOE Savannah River (Operable Unit 7) site is part of the 300-square mile
Savannah River Site (SRS) facility located in Aiken, Barnwell, and Allendale Counties,
South Carolina. Land use in the area is predominantly agricultural, with no
residential uses. The Savannah River Site (SRS) is a secured, national defense-related
facility, co-operated by the Westinghouse Savannah .River Company, that produces
tritium, plutonium, and other special nuclear materials. The site also provides
nuclear materials for the space program, and conducts medical, industrial, and research
efforts. From 1955 to 1988, the central area of the site, termed the H-Area, was used
as a Hazardous Waste Management Facility (HWMF). The H-Area HWMF consists of four
unlined, earthen surface impoundments located near the center of SRS. During its
operation, the facility received waste effluents from H-Area chemical separation
facilities processes such as a nitric acid recovery unit, waste storage system
evaporator overheads, and general purpose evaporator overheads. In 1962, one of three
basins was closed and replaced by a fourth basin. The three remaining basins had a
combined maximum operating capacity of 26.5 million gallons of wastewater. Significant
amounts of nitrate and caustic were received from wastewater discharge into the H-Area
basins, and these radioactive releases to the three basins were greater than 99 percent
(See Attached Page)
17. Documant Analysis a. Descriptors
Record of Decision - USDOE Savannah River (Operable Unit 7), SC
Fifth Remedial Action
Contaminated Medium: None
Key Contaminants: None
b. Mantlfian/Opan-EndadTanns
c. COSATI Bold/Group
18. Availability Statement
19. Security Class (This Report)
None
20. Security Class (THs Page)
None
21. No. of Pages
20
22. Price
(See ANS1-Z39.18)
See Instructions an R»nn*
OPTIONAL FORM 272 (4-77)
(Formerly NTO-35)
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EPA/ROD/R04-93/164
USDOE Savannah River (Operable Unit 7), SC
Fifth Remedial Action
Abstract (Continued)
tritium. Several studies showed that 90 percent of the radionuclides/ cations, and anions
were concentrated within the top 1 foot of basin soil. In 1988, a RCRA closure plan for
the site was developed. The closure of the H-Area HWMF began in 1989, and was completed
in early 1991. Closure activities included removing standing water remaining in the 3
original basins and in the basin added in 1962; stabilizing the basin sludge with a layer
of granite, limestone, and blast furnace slag; constructing a low permeability multi-layer
cap over the basins; and restoring the area. The site closure prevents physical exposure
to contaminants and mitigates further migration of contaminants from the H-Area HWMF to
ground water through rainwater percolation. The H-Area HWMF is being routinely inspected
for a minimum of 30 years and institutional controls, including deed restrictions, have
been implemented. This ROD addresses contaminated soil and sludge in the H-Area, as OU7.
Future RODs will address the ground water beneath the site. EPA investigations indicate
that the previous RCRA closure of the site sufficiently has reduced the threat to human
health and the environment; therefore, there are no contaminants of concern affecting this
site. Future RODs will address the remaining OUs at this site.
The selected remedial action for this site is no further action, with ground water
monitoring. EPA has determined that the previous RCRA closure of the site has prevented
the risk of physical exposure to site contaminants, reduced further migration of site
contaminants to ground water, and that the site poses no threat to human health and the
environment. However, as a condition of the RCRA Hazardous Waste Permit, post closure
ground water monitoring is required to verify that no unacceptable exposures to potential
hazards posed by conditions at OU7 occur in the future. There are no present worth or O&M
costs associated with this no action remedy.
PERFORMANCE STANDARDS OR GOALS:
Not applicable.
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WSRC-RP-93-1043
Revision 1
September 2, 1993
UNITED STATES DEPARTMENT OF ENERGY
SAVANNAH RIVER SITE
FINAL RECORD OF DECISION
REMEDIAL ALTERNATIVE SELECTION
FOR
(bui)
H-Area Hazardous Waste Management Facility (U)
Prepared by
WESTINGHOUSE SAVANNAH RIVER COMPANY
SAVANNAH RIVER SITE
AIKEN, SC 29802
PREPARED FOR THE US DEPARTMENT OF ENERGY UNDER
CONTRACT DE-AC09-89SR18035
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September 2, 1993
DECLARATION FOR THE FINAL RECORD OF DECISION
Site Name and Location
H-Area Hazardous Waste Management Facility (HWMF)
Savannah River Site
Aiken County, South Carolina
Appendix H of the Federal Facility Agreement (FFA) lists this unit as the H-Area
Hazardous Waste Management Facility (Building Numbers 904-44G, 904-45G,
904-46G, and 904-56G).
Statement of Basis and Purpose
This document presents the selected final preventive action for the H-Area
HWMF Operable Unit at the Savannah River Site (SRS), which was developed
in accordance with the Comprehensive Environmental Response,
Compensation and Liability Act of 1980 (CERCLA), as amended by the
Superfund Amendments and Reauthorization Act of 1986 (SARA), and to the
extent practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP). This decision is based on the Administrative Record
File for this unit
Description of the Selected Remedy
The selected final action remedy involved the stabilization and placement of all
contaminated materials under a low permeability cap. This remedy prevents
physical exposure to contaminants and mitigates further migration of
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" September 2, 1993
contaminants to the groundwater by minimizing a liquid medium pathway
(rainwater percolation) for transport.
No further action is necessary for the unit. However, as a condition of the RCRA
Hazardous Waste Permit, post closure groundwater monitoring is required to
verify that no unacceptable exposures to potential hazards posed by conditions
at the operable unit occur in the future.
The major components of the preventive action included:
1) Elimination of free liquids by removing liquid waste and solidifying the
remaining waste and residues,
2) Stabilization of the remaining wastes to a load bearing capacity sufficient to
support the cover system,
3) Placement of a final cover over the surface impoundment. The cover
consists of a layer of backfill, a nine inch sand layer, a two foot layer of
compacted kaolin clay, a geotextile fabric, topped with two feet of topsoil to
support a vegetative cover. (See below)
u
Vegetative Cover
Top Sol (2 ft)
Geotextile Fabric
Sand Drainage Layer (9 In)
Low Permeability day Layer (2 ft)
dean Soil Backfill and Contour Layer
Limestone and Blast Furnace Slag (1 ft)
Granite Aggregate (3-6 ft)
Basin Sediments
II
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* September 2, 1993
4) The H -Area HWMF is being routinely inspected for a minimum of 30 years to
verify the integrity of the cover system, fences, signs, etc. Any necessary repairs
to the cap will be made as part of the maintenance program.
5) Access to the H-Area HWMF is restricted to authorized personnel with
appropriate training on applicable requirements. The survey plat and records
associated with deed restricted use of the H- Area HWMF have been filed with
Aiken County, SC.
Declaration Statement
Previous action taken at the H-Area HWMF was under a RCRA Closure Plan
approved by the state of South Carolina and was protective of human health
and the environment. Therefore, no further remedial action is necessary under
CERCLA. To ensure continued protection of human health and the
environment, this remedial action will be reviewed every 5 years, consistent
with the requirements of the NCP.
1. Roberson
I Assistant Manager for Environmental
Restoration and Solid Waste
U.S. Department of Energy
Patrick M. Tobin
Acting Regional Administrator,
U.S. Environmental Protection Agency
Region IV
III
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WSRC-RP-93-1043
Revision 1
September 2, 1993
SUMMARY OF FINAL ACTION
REMEDIAL ALTERNATIVE SELECTION
FOR
H-Area Hazardous Waste Management Facility (U)
Prepared by
WESTINGHOUSE SAVANNAH RIVER COMPANY
SAVANNAH RIVER SITE
AIKEN, SC 29802
PREPARED FOR THE US DEPARTMENT Of ENERGY UNDER
CONTRACT DE-AC09-
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! September 2, 1993
DECISION SUMMARY
TABLE OF CONTENTS
Section Page
I. Site and Operable Unit Names, Locations, and 1
Descriptions
II. Operable Unit History and Compliance History 4
III. Highlights of Community Participation 7
IV. Scope and Role of Operable Unit within the Site 7
Strategy
V. Summary of Operable Unit Characteristics 7
VI. Summary of Operable Unit Risks 8
VII. Explanation of Significant Changes 9
Appendices
A. References for Development of ROD Format 10
B. Responsiveness Summary 11
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, September 2. 1993
I. Site and Operable Unit Names, Locations, and Descriptions
The Savannah River Site (SRS) occupies approximately 300 square miles (483
km) adjacent to the Savannah River, principally in Aiken and Barnwell Counties
of South Carolina (Figure 1). SRS is a secured facility with no permanent
residents. The site is approximately 25 miles (40 km) southeast of Augusta,
Georgia, and 20 miles (32 km) south of Aiken, South Carolina. The average
population density in the counties surrounding SRS ranges from 23-560 people
per square mile (60-1452 per square km) with the largest concentration in the
Augusta, Georgia, metropolitan area. Based on 1980 census data, the
population within a 50-mile (80 km) radius of SRS is approximately 555,100.
SRS is owned by the United States Department of Energy (DOE).
Westinghouse Savannah River Company (WSRC) is the manager and
operating contractor for DOE. SRS produces tritium, plutonium, and other
special nuclear materials for national defense. The site also provides nuclear
materials for the space program, and conducts medical, industrial, and research
efforts. The H-Area HWMF is a source specific operable unit within the H-Area
Fundamental Study Area. The H-Area HWMF consists of three unlined, earthen
surface impoundments located in the center of SRS, southwest of Road E and
north of road 4 approximately 6 miles (10 km) from the nearest site boundary
(Figure 2).
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SAVANNAH RIVER
SITE
Figurel Location of the Savannah River Site (SRS)
(Source: Modified from the Savannah River Environmental Report, 1990)
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Figure 2 H-Area HWMF
(Source: Modified from the EIO for the H-Area Seepage Basins, 1987)
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II. Operable Unit History and Compliance History
Operable Unit History
The H-Area HWMF operated from 1955 until November 7, 1988. The original
H-Area HWMF consisted of basins H-1, H-2 and H-3 and operated from 1955 to
1962. In 1962 H-3 was replaced by H-4.
The dimensions and volumetric capacity of the basins were as follows:
H-1:90 ft x 240 ft x 9 ft, 1.1 million gallons
H-2:110 ft x 460 ft x 9 ft, 2.8 million gallons
H-3:350 ft x 480 ft x 17 ft, 9.4 million gallons
H-4: (130-430) ft x 2400 ft x 8 ft. 22.6 million gallons
At the time of closure, the H-Area HWMF (basms H-1. H-2, and H-4) had a
combined maximum operating capacity of 26.5 millcn gallons of wastewater.
The H-Area HWMF received waste effluents from H-Area chemical separation
facilities processes such as the nitric acid recovery urut. waste storage system
evaporator overheads, and general purpose evaporator overheads.
The H-3 basin was not a RCRA regulated un< but was identified as a RCRA
3004(u) unit requiring investigation and rem«<*ation. It was decided to
incorporate basin H-3 into the RCRA closure.
The four basins were dosed by dewatering. pnyacafty and chemically
stabilizing the remaining sludges and placing a prate** mutHayer cover
system (Figure 3) over them reduce rainwater contact w9> basin bottoms.
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Vegetative Cover
Top Soil (2 ft)
Geotextile Fabric
Sand Drainage Layer (9 In)
Low Permeability Clay Layer (2 ft)
Clean Soil Backfill and Contour Layer
Limestone and Blast Furnace Slag (1 ft)
Granite Aggregate (3-6 ft)
Basin Sediments
Figure 3 H-Area HWMF Cap Cross Section
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Compliance History
Preventive actions at the H-Area HWMF were conducted pursuant to the
requirements of the Resource Conservation and Recovery Act (RCRA) per
Settlement Agreement 87-27-SW. In 1988, a RCRA Closure Plan was
submitted to the South Carolina Department of Health and Environmental
Control (SCDHEC). The closure plan underwent several revisions prior to
approval by SCDHEC in 1989. Closure of the unit was begun in 1989 and
completed in May 1991. The H-Area HWMF was certified closed in July 1991. In
October 1991, the closure certification was accepted by SCDHEC as being in
compliance with RCRA requirements. A RCRA Part B Permit Application for
Post-Closure Care was submitted in December 1990 and a Hazardous Waste
Permit was effective November 1992.
Closure activities specifically included removal of standing water remaining in
the basin; stabilization of the basin sludge with a layer of granite, limestone, and
blast furnace slag; construction of a low permeability cap over the basin; and
restoration of the area.
Preventive activities at the H-Area HWMF became subject to CERCLA when the
entire SRS facility was placed on the National Priorities List (NPL) in December
1989. The H-Area HWMF is a source-specific operable unit within the H-Area
Fundamental Study Area.
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III. Highlights of Community Participation
The public review period that ran from 18 June 93 - 2 August 93. SCDHEC
submitted comments on the Proposed Plans which have been incorporated into
this ROD, where appropriate.
IV. Scope and Role of Operable Unit Within the Site Strategy
The selected remedy involved the placement of all contaminated materials
under a low permeability cap. The remedy prevents physical exposure to
contaminants and mitigates further migration of contaminants from the H-Area
HWMF to groundwater by minimizing a liquid medium pathway (rainwater
percolation) for transport.
V. Summary of Operable Unit Characteristics
Waste effluents from H-Area chemical separation facilities processes such as
the nitric acid recovery unit, waste storage system evaporator overheads, and
general purpose evaporator overheads were discharged to the H-Area HWMF.
Significant amounts of nitrate and caustic were received. Radioactive releases
to these basins were greater than 99% tritium. Several studies were conducted
to characterize the subsoils. A 1984 soil coring study showed that
approximately 90% of the radionuclides, cations, and anions were concentrated
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within the top 1 foot of basin soil. The chemicals of concern at the H-Area
HWMF are arsneic, barium, cadmium, lead, mercury, cobalt-60, copper, nickel,
vanadium, zinc, tetrachloroethylene, gross alpha, gross beta, nitrate, radium-
226, radium-227, tritium, iodine-129, strontium-90, technetium-99, uranium-
233/234, and carbon-14.
VI. Summary of Operable Unit Risks
Due to the previous H-Area HWMF RCRA preventive action, No Further Action
under CERCLA is necessary for this unit. The RCRA preventive action is
protective to human health and the environment and satisfies CERCLA
requirements.
Contaminated sediments of the H-Area HWMF were stabilized in the basin
during closure. The basin then was covered with a low permeability soil cap.
Therefore, exposure through surface soil and sediment pathways is minimized
because of this RCRA cap.
Preventive alternatives were developed for the H-Area HWMF based on
effective technologies available at the time the RCRA Closure Plan was
prepared. The RCRA Closure Plan was initially submitted to SCDHEC in
early 1989 and was approved, following several revisions, in Junel989.
8
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Options regarding the H-Area HWMF evaluated at that time included:
Alternative 1
No Action
Alternative 2
No Waste Removal, Waste Consolidation, Treatment, and Closure
Alternative 3
Waste Removal and Closure
Alternative 2 was selected within the RCRA closure process in 1988 as the most
technically effective of the three alternatives for protection of human health and
the environment. Closure of the H-Area HWMF was begun in 1989 and
completed in July 1991. The closure certification was accepted by SCDHEC in
1991 as being in compliance with RCRA and state requirements. The closure is
considered a final action under CERCLA
VII. Explanation of Significant
There were no significant changes.
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Appendix A
References for Development of ROD Format
Weeks, Victor, 1993. "Regarding Records of Decision, F-Area and H-Area,
Savannah River Site, Aiken , South Carolina", Letter to Goidell (DOE),
Savannah River Site, Aiken, SC, April 14, 1993.
EPA, 1991. "Guide to Developing Superfund No Action, Interim Action, and
Contingency Remedy RODs," OSWER Publication 9355.3-02FS-3, U.S.
Environmental Protection Agency, Washington, D.C., April 1991.
WSRC, 1992. "Draft RCRA Facility Investigation/Remedial Investigation
Program Plan," WSRC-RP-89-994, Chapter 15, Westinghouse Savannah
River Company, Aiken, South Carolina, May 1992.
10
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