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APPENDIX D
DESCRIPTIONS OF DOE'S ENVIRONMENTAL
QUALITY TECHNICAL CATEGORIES
These descriptions are based largely on those in the Department of
Energy's (DOE's) Environmental Quality (EQ) research and development
(R&D) portfolio document (DOE, 2000b) and are intended to provide the
reader with an overview of the magnitude and duration of DOE's "EQ
challenges" (see Sidebar 2.3~. They are not intended to represent a
comprehensive description of the problem areas or the types of R&D
activities currently being conducted by DOE.
Manage High-Level Waste
High-level waste (HLW) is highly radioactive material resulting from
reprocessing of spent nuclear fuel, which includes both liquid waste and
solid residues. Large quantities of HLW were generated during
production of nuclear weapons and reprocessing of defense production
reactor fuels. There are 280 large radioactive waste storage tanks and
more than 63 smaller underground storage tanks across the DOE
complex that contain more than 340,000 cubic meters (90 million
gallons) of HLW waste. Most of these tanks have exceeded their design
life, some have leaked, and all represent potential occupational and
public risks.
The waste is currently stored at five main locations in both solid and
liquid form: (1 ) Savannah River, South Carolina; (2) Hanford,
Washington; (3) Idaho National Engineering and Environmental
Laboratory (INEEL); (4) Oak Ridge Reservation, Tennessee; and (5)
West Valley Demonstration Project, New York. To protect the public and
the environment, much of this waste must be retrieved from the tanks
and converted into an appropriate form for long-term disposal. Some
HLW has been immobilized in glass at Savannah River and West Valley.
DOE has signed federal facility agreements with state and federal
regulators that drive the scope and schedule for cleanup and closure of
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the tanks. DOE estimates that HLW cleanup will continue until at least
2046, at a total projected life-cycle cost of $54 billion. In fiscal year 2000,
DOE spent approximately $57.6 million on R&D to address needs related
to the management of high-level waste. DOE also recognizes that after
cleanup most sites that stored HLW will require long-term institutional
management measures indefinitely to protect human health and the
environment (see "Long-Term Institutional Management" below).
Manage Mixed Low-level/Transuranic Waste
Mixed low-level waste (MLLW) is low-level waste that contains both
chemically hazardous and radioactive components. Transuranic (TRW)
waste is any waste, except for HLW, containing more than 100
nanocuries per gram of long-lived (~20 years), alpha-emitting TRU
radionuclides. TRU waste is produced primarily from reprocessing of
irradiated fuel and fabrication of nuclear weapons and contains isotopes
such as plutonium and americium. Unlike HLW, TRU waste is non-heat
bearing. Low-level waste is waste that is not spent fuel, HLW, or uranium
or thorium mill tailings.
Thirty-six DOE sites store about 165,000 m3 of mixed low-level and
transuranic waste. Considerable amounts of TRU waste also contain
hazardous constituents subject to regulation under the Resources
Conservation and Recovery Act (RCRA) or the Toxic Substances Control
Act. Since 1970, DOE has placed TRU waste in retrievable storage, such
as metal drums or boxes, either on storage pads, in buildings, or in
tanks. TRU waste is managed at 21 sites. DOE has begun disposal of
stored post-1970 TRU waste at the Waste Isolation Pilot Plant (WIPP)
near Carlsbad, New Mexico. Because MLLW contains chemically
hazardous as well as non-transuranic radioactive materials, it is subject
to regulation under both RCRA and the Atomic Energy Act. The storage,
treatment, and disposal of MLLW are subject to state and federal
regulations. The estimated life-cycle cost for management and
disposition of mixed low-level and TRU waste is more than $18 billion. In
fiscal year 2000, DOE spent approximately $29.1 million on R&D related
to the management of mixed low-level/TRU waste.
Manage Spent Nuclear Fuel
Spent nuclear fuel (SNF) is irradiated nuclear fuel that has not been
reprocessed. The United States operated 14 nuclear defense production
reactors between 1944 and 1988 to produce plutonium and tritium for
nuclear warheads. In addition, the United States operated many other
test reactors to encourage and support both commercial and military
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145
reactor developments. (The spent nuclear fuel arising from the operation
of commercial nuclear power plants is described below.) During that
time, most of the nuclear fuel rods and targets irradiated in the reactors
were reprocessed to extract the plutonium or tritium and the remaining
enriched uranium for reuse. In addition, the U.S. Navy operated many
nuclear propulsion reactors from which the fuel assemblies were
processed to recover and reuse the remaining fissile uranium. DOE's
SNF is not categorized as waste, but it is highly radioactive and must be
stored in special facilities that shield and cool the material. Most SNF is
stored in indoor pools under water, although some spent fuel is kept in
dry storage.
Three DOE sites (INEEL, Savannah River, and Hanford) manage
most of the SNF in the DOE complex. Hanford has an inventory of over
2,100 metric tons heavy metal (MTHM) of SNF from its production
reactors. After washing, packaging, and drying, this SNF will be
transferred to dry storage until shipment (either to a repository or to an
alternative treatment system). INEEL has an inventory of 270 MTHM of
SNF, and expects to receive an additional 60 MTHM. After on-site
storage, drying, and packaging, all SNF is expected to be shipped off-
site to a repository for disposal. Savannah River has an inventory of 20
MTHM, and expects to receive an additional 30 MTHM from off-site
sources. The SNF is expected to be prepared and placed in an off-site
geologic repository (the same one as for commercial spent fuel and
HEW). The total life-cycle cost for management and preparation for
disposal of DOE's SNF is estimated to be about $7 billion (DOE, 2000b).
In fiscal year 2000, DOE spent approximately $12 million on R&D related
to the management of spent nuclear fuel.
Manage Nuclear Materials
A major consequence of the end of the Cold War has been a
decrease in the number of U.S. nuclear weapons deployed around the
world. This decrease resulted in nuclear weapons components being
returned to DOE and classified as surplus materials (approximately 200
metric tons of U.S. weapons-usable fissile materials, which includes
highly enriched uranium and plutonium, are classified as surplus
materials). Disposition of this surplus material will be carried out either by
making it into reactor fuel and burning it in electricity-producing
commercial reactors (producing spent fuel) or by immobilizing the
material mixed with high-level waste. In both cases, the resulting
materials will be prepared for disposal in the geological repository.
Other nuclear materials are present in weapons complex facilities
that were shut down in the late 1980s and early 1990s due to concerns
over safety and environmental problems, and the end of the Cold War.
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DOE also has an inventory of over 700,000 metric tons of depleted
uranium hexafluoride and a variety of special purpose isotopes like U-
233. The estimated life-cycle cost for management and disposition of
DOE's nuclear materials is approximately $7 billion (DOE, 2000b). In
fiscal year 2000, DOE spent approximately $7.6 million on R&D related
to the management of nuclear materials.
Dispose of High-Level Radioactive Wastes, Spent Nuclear Fuels,
and Nuclear Materials
DOE is responsible for providing for the permanent disposal of U.S.
high-level radioactive waste and SNF (Public Law 97-425~. The Yucca
Mountain Site in Nevada has been designated as the only site to be
characterized to determine its suitability for a geologic repository (Public
Law 100-203~. The types of waste that will be disposed of in the geologic
repository consist of commercial spent fuel (including mixed oxide spent
fuel [i.e., fuel that contains both uranium and plutonium from weapons
dismantlement]), high-level waste (including immobilized plutonium), and
DOE spent fuel (including naval- spent fuel). Other wastes, such as
greater-than-class-C, may also be disposed of in the repository.
Commercial spent fuel consists of fuel assemblies discharged from
electricity-generating nuclear reactors and is located at 72 nuclear power
plant sites and one independent storage site in 33 states. The total
inventory of spent fuel at the end of 1998 was estimated to be about
38,000 MTHM, and the expected inventory in 2040 is projected to be
about 85,000 MTHM. High-level waste to be disposed of is immobilized
(generally as a borosilicate glass or a ceramic) and encased in metal
canisters. It is estimated that approximately 22,000 canisters will be
produced through 2035 (including those that will contain immobilized
surplus weapons-usable plutonium). The DOE spent fuel inventory
projected to the year 2035 is estimated to be 2,500 MTHM.
DOE plans to submit a site suitability recommendation for the Yucca
Mountain Site to the President in 2001, and if the site is determined to be
suitable and approved by both the President and Congress (after
presidential approval, the state of Nevada can submit a notice of
disapproval that can be overridden by a majority vote of both houses of
Congress), to prepare and submit a license application to the U.S.
Nuclear Regulatory Commission in 2003 for construction authorization
for the repository. To obtain the license, DOE must demonstrate that a
repository can be constructed, operated, monitored, and eventually
closed without unreasonable risk to the health and safety of workers and
the public. The repository schedule calls for initial waste emplacement in
2010, followed by several decades of operation and further decades of
monitoring and performance confirmation. In fiscal year 2000, DOE spent
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approximately $47 million on R&D to address needs related to the
disposal of high-level radioactive waste, spent nuclear fuels, and nuclear
materials.
Environmental Remediation of Contaminated Sites (Lands and
Waters)
Environmental remediation involves the removal or stabilization of
radioactive and/or hazardous contaminants in soil, fractured bedrock,
and groundwater. The primary objectives are to identify, contain,
remediate, and remove contamination, and to validate that environmental
remediation has achieved the desired end state. Approximately 3 million
cubic meters (100 million cubic feet) of solid radioactive and hazardous
wastes are buried in the subsurface throughout the DOE complex. The
largest contamination challenges are at the INEEL, Oak Ridge, Hanford,
Rocky Flats, and Savannah River sites. Contaminants are located in the
subsurface both above and below the water table. DOE estimates that
75 million cubic meters (2.6 billion cubic feet) of soil and 1.8 billion cubic
meters (475 billion gallons) of groundwater are contaminated and require
remediation. Contaminants include hazardous metals such as chromium,
mercury, and lead; radioactive laboratory and processing waste;
explosive and pyrophoric materials; solvents; and numerous
radionuclides. The total life-cycle cost of environmental remediation
activities through 2070 is estimated to be greater than $13 billion (DOE,
2000b). In fiscal year 2000, DOE spent approximately $52 million on
R&D related environmental remediation of contaminated DOE sites.
Deactivation and Decommissioning of Contaminated Facilities
Many of the more than 20,000 DOE facilities that were used to
support nuclear weapons production and other activities are
contaminated with radioactive materials, hazardous chemicals, asbestos,
and lead. To reduce the potential for release of radioactive and
hazardous materials to the environment, the risk of industrial safety
accidents, and the costs of monitoring and maintaining these facilities,
DOE plans to deactivate and decommission (D&D) such facilities.
Deactivation is defined as activities to reduce the physical risks and
hazards at these facilities, to reduce the costs associated with monitoring
and maintenance of these facilities (i.e., facility mortgage), and make
these facilities available for potential reuse or eventual decommissioning.
Decommissioning is defined as activities associated with
decontamination, demolition, and final disposition of the facility and the
equipment contained within. The estimated life-cycle cost of D&D
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activities for facilities currently under DOE responsibility is $12.5 billion.
In fiscal year 2000, DOE spent approximately $12.7 million on R&D to
address needs related to the deactivation and decommissioning of
contaminated DOE facilities.
Long-Term Stewardship
Of the 144 contaminated sites currently under its control, DOE
estimates that fewer than 25 percent will be cleaned up sufficiently to
allow unrestricted use. At many sites, radiological and non-radiological
hazardous wastes will remain, posing risks to humans and the
environment for tens or even hundreds of thousands of years. For these
sites, a broad-based, systematic approach that integrates contaminant
reduction, contaminant isolation, and stewardship will be required to
protect human health and the environment (NRC, 2000a; DOE, 1999a,
2001 b). DOE estimates that it currently spends approximately $64 million
annually on long-term stewardship activities, and these costs will
increase to nearly $100 million annually by 2050, when all sites are
expected to be closed (DOE, 2001 b).
Minimization of the Risk of Newly Generated Radioactive and
Hazardous Waste
The recent adequacy analysis of the EQ R&D portfolio (DOE, 2000g)
recommended that a new category of R&D activities be defined to
minimize the risk of newly generated DOE radioactive and hazardous
waste. DOE currently has no complex-wide R&D program to minimize
the generation of new wastes, although site specific work is in progress
to address local waste management programs (DOE, 2000g).
Representative terms from entire chapter:
doe spent
