APPENDIX C
Program Drivers: Materials Destined for Geologic Disposal
Spent nuclear fuel (SNF) generated by commercial nuclear reactors constitutes by far the largest inventory of nuclear materials destined for geologic disposal. However, a repository is also essential for the disposition of an array of other nuclear materials that are managed by the Department of Energy (DOE). This appendix summarizes current planning assumptions about how the disposal capacity of the repository would be allocated among all waste forms. It also consolidates some historical, technical, and policy information about these DOE-managed nuclear materials, and reports current and projected inventories of those materials and of commercial SNF.
Allocation of repository capacity: current planning assumptions
Projected inventories and the statutory limit on the quantity of waste emplaced
The Nuclear Waste Policy Act (NWPA) of 1982 provides that the Nuclear Regulatory Commission (NRC) may approve the emplacement in the first repository of a quantity of spent fuel containing no more than 70,000 metric tons of heavy metal (MTHM) or a quantity of solidified high-level waste (HLW) resulting from the reprocessing of such quantity of spent fuel. The 1987 Nuclear Waste Policy Amendments Act requires the Secretary to report to the President and to Congress on or after January 1, 2007, but not later than January 1, 2010, on the need for a second repository. The total inventory of commercial SNF and DOE-managed nuclear materials requiring geologic disposal, projected through 2035, exceeds 70,000 MTHM. Due to projected nuclear power reactor license renewals, the total may reach approximately 105,000 MTHM.
Based on a Presidential decision to use disposal capacity at repositories developed pursuant to the NWPA for disposal of high-level radioactive waste resulting from atomic energy defense activities, the Office of Civilian Radioactive Waste Management's (OCRWM) planning basis allocates 7,000 MTHM of the 70,000 MTHM statutory limit to DOE-managed nuclear materials. Of that 7,000 MTHM, DOE has specified that two-thirds would be high-level radioactive waste and one-third would be DOE and naval SNF.
For planning purposes, we analyze a range of design and operational capacities. The lower bound of the proposed repository capacity for spent fuel is consistent with the 70,000 MTHM statutory limit. The upper bound is based on projections of the total quantity of SNF and high-level radioactive waste requiring disposal. Analyses of the upper bound enable us to evaluate the actual physical capability of a potential repository at the Yucca Mountain site to safely isolate these wastes. The analyses of lower and upper bounds support site characterization, design work, a possible site recommendation, the environmental impact statement (EIS), possible preparation of a license application, and a definition of repository operations.
Description of materials destined for geologic disposal
This section provides background information on projected quantities of material destined for geologic disposal. The projections are subject to change as decisions on materials disposition are made and carried out.
Consistent with information presented in the draft EIS for the proposed repository at Yucca Mountain, this section divides the materials destined for geologic disposal into three groups: (1) commercial SNF, (2) DOE-managed SNF, and (3) DOE-managed high-level radioactive waste.
The table and figure at the end of this appendix provide an overview of the quantities of nuclear materials destined for geologic disposal and indicate the sources of data for information presented throughout this appendix.
Commercial spent nuclear fuel
Background
Commercial SNF is fuel that has been withdrawn from a nuclear reactor following irradiation. The fuels discussed in this section are those removed from commercial reactors. Nuclear power reactors store SNF in spent fuel pools under licenses from the NRC. They can use a combination of storage options: (1) in-pool storage and (2) above-grade dry storage in an independent spent fuel storage installation.
The final form of commercial SNF to be disposed of in the proposed repository would be reactor fuel assemblies as they are removed from reactors. The proposed repository would receive spent fuel assemblies or SNF packaged in canisters. In its Record of Decision for the Surplus Plutonium Disposition Final Environmental Impact Statement, issued in January 2000, DOE decided that up to 33 metric tons of the up to 50 metric tons of surplus plutonium would be converted to a mixed oxide fuel that would subsequently be burned in commercial reactors and disposed of in a repository as SNF.
Current and projected inventories
By December 2000, SNF containing 42,700 MTHM was stored at 72 commercial power reactor sites and one independent storage site (this projection does not include DOE-owned sites). Those sites are located in 33 States. Of the 118 reactors at these 72 sites, 14 are no longer in operation. Fifteen reactor sites have added NRC-licensed (as per 10 CFR 72) onsite independent spent fuel storage installations utilizing above-grade dry storage to supplement their in-pool storage capacity; others are approaching full pool capacity and will require additional storage.
Based on projections made in Fiscal Year 2000, by 2035, when the last of the existing 118 commercial power reactors will have completed its initial 40-year license period, SNF containing a total of about 83,800 MTHM will have been generated. This inventory includes SNF resulting from burning approximately 33 MTHM of surplus weapons-usable plutonium in the form of mixed-oxide fuel in commercial nuclear reactors. The resulting SNF would be stored at the reactor sites until it was transported to a repository for disposal.
DOE-managed spent nuclear fuel
Background
DOE stores most of its SNF at three locations: (1) the Hanford site in Washington State, (2) the Idaho National Engineering and Environmental Laboratory (INEEL), and (3) the Savannah River site in South Carolina. A relatively small amount is stored at the Fort St. Vrain dry storage facility in Colorado. Small quantities remain at other locations. The inventory of SNF created by the Department of the Navy from propulsion of its submarines and surface vessels is included in DOE's SNF inventory.
Over the past 40 years, DOE and its predecessor organizations have generated more than 200 varieties of SNF from weapons production, nuclear propulsion, and various research endeavors. Because there are so many varieties of DOE SNF and to facilitate total system performance assessments, fuel was grouped into 16 categories. To define the categories, regulatory requirements were used to identify the parameters that would affect the performance of DOE SNF in a repository and that would support analyses needed for a license application. A list of these 16 categories is included in Appendix A of the draft EIS for the proposed geologic repository at Yucca Mountain.
Current and projected inventories
Through the year 2035, the total inventory of DOE SNF is projected to be approximately 2,500 MTHM. The following paragraphs provide an overview of the materials and their respective quantities that constitute the total inventory.
- Hanford Site. Most of the DOE inventory of SNF, 2,100 MTHM, is now at the Hanford site in Washington State, where SNF was generated in the N-Reactor for use in the weapons program. DOE plans to continue with plans to move this fuel, which is metallic-based, from wet storage to dry storage at the Hanford site.
- Idaho National Engineering and Environmental Laboratory. DOE SNF stored at this site originated in activities to promote the peaceful uses of atomic energy, beginning with the passage of the Atomic Energy Act of 1954. (The naval SNF stored at this site is discussed below.) The approximately 240 MTHM inventory, projected to remain essentially unchanged through 2035, includes SNF from demonstration reactors, from research and development activities, and from activities to demonstrate storage technologies and characterization for disposal. The research reactor fuel stored at this site is not aluminum-based; it will include 1.0 MTHM of foreign research reactor SNF. Debris from the Three Mile Island reactor is also stored at this site. Under a consent agreement among DOE, the Department of the Navy, and the State of Idaho, DOE shall remove all SNF stored in that State by January 1, 2035.
- Savannah River Site. SNF from production reactors has been stored at this South Carolina site, and some of it has been converted to high-level radioactive waste for disposal. The 44 MTHM of SNF in storage includes remaining unprocessed production reactor fuel and some domestic research reactor fuel. This inventory is projected to remain unchanged through the year 2035. DOE has also designated this site for storage of aluminum-clad SNF from domestic and foreign research reactors. The uranium in foreign reactor fuel was originally exported by the U.S. Government under the Atoms for Peace Program. In keeping with nuclear nonproliferation policies, foreign research reactor fuel is being returned to this country and placed under DOE management. Up to 16 MTHM is projected to be returned, of which approximately 15 MTHM will be stored at the Savannah River site.
- Naval SNF. The Department of the Navy fabricates its own nuclear fuel for its nuclear-powered vessels using highly enriched uranium. For many years, naval SNF was shipped to the Idaho Chemical Processing Plant, where DOE reprocessed it to recover the uranium. Following DOE's termination of reprocessing activities in 1992, a consent agreement was reached in October 1995 between the Federal Government and the State of Idaho to allow the temporary storage of naval SNF at INEEL. Under the consent agreement, naval SNF will be among the early shipments to a repository. In 1996, the Navy decided that it would store its SNF in dual-purpose canisters in Idaho prior to shipping it to a geologic repository for disposal. The current inventory consists of approximately 14 MTHM and is projected to total approximately 65 MTHM by 2035.
The total projected inventory of DOE SNF includes approximately 15 MTHM stored at other sites, including some commercially irradiated SNF now under DOE management. In addition to the quantities of DOE-managed SNF discussed above, 60 metric tons of sodium-bonded SNF, most of it stored at INEEL and Argonne National Laboratory-West in Idaho, are being evaluated to determine whether it requires treatment to make it suitable for disposal. DOE is preparing an EIS for proposed disposition of this SNF, as required by the National Environmental Policy Act. If the fuel is treated, it could be disposed of as high-level radioactive waste.
High-level radioactive waste
Background
High-level radioactive waste inventories have resulted from past reprocessing of SNF to recover plutonium and uranium. DOE originally intended to reprocess most of its SNF, and reprocessing began at a number of Federal sites as early as the 1940s. In 1985, when President Reagan decided that high-level radioactive waste resulting from atomic energy defense activities could be disposed of in the civilian repository, DOE and naval SNF were still being reprocessed. Reprocessing continued until 1992, when the Administration discontinued the practice.
In the January 2000 Record of Decision for the Surplus Plutonium Disposition Final Environmental Impact Statement, DOE decided that up to approximately 17 metric tons of the up to 50 metric tons of surplus plutonium would be immobilized in a ceramic form to be disposed of in canisters of vitrified HLW.
Current and projected inventories
Radioactive wastes from reprocessing are stored as aqueous solutions, sludges, and calcines at the INEEL, Hanford, and Savannah River sites. If the decision is made to send these wastes to a repository, DOE will solidify them as borosilicate glass in canisters prior to transport. The canisters will be safely stored near the vitrification site until they are transported to a repository for disposal. At the Savannah River site, the production of borosilicate glass canisters has already begun. A total of 21,847 canisters of high-level radioactive waste is projected to be produced at DOE sites through 2035. In addition, the West Valley Demonstration Project in New York State, a facility now managed by DOE, is vitrifying high-level radioactive waste that resulted from commercial reprocessing of SNF. It is projected that 300 canisters of vitrified commercial HLW will be produced at West Valley.
Other nuclear materials no longer essential to national security needs
Through the work of its Nuclear Materials Stewardship Initiative, DOE is examining whether certain nuclear materials no longer essential to national security needs should be maintained as a national resource or disposed of, possibly in the geologic repository that OCRWM would develop.
These materials include curium and americium, now in solutions; metals and oxides of neptunium-237 at the Savannah River site; and uranium-233-rich materials at Oak Ridge and INEEL. If DOE determines that disposal in a repository is warranted, total system performance assessment analyses would evaluate the impacts on repository system performance of disposing of these materials in a repository.
Summary of quantities of materials intended for geologic disposal
The information in the table below is based on references that support both the Yucca Mountain repository viability assessment and the draft EIS for the proposed repository at Yucca Mountain. They identify quantities of materials requiring geologic disposal that are projected through 2035 and quantities allocated to the first repository for planning purposes. The map in the introduction to this report indicates the location of these materials.
In the table below, quantities of SNF are expressed in MTHM. Other measures are also important for expressing quantities of SNF and high-level radioactive waste: the table expresses quantities of high-level radioactive waste in terms of canisters of vitrified high-level radioactive waste, and it identifies the number of waste packages that would be required for SNF and high-level radioactive waste.
In addition, the table reflects DOE's current plans to dispose of 50 metric tons of surplus weapons-usable plutonium by both immobilizing it in ceramic, to be disposed of in containers of vitrified high-level radioactive waste, and irradiating it in mixed oxide fuel that would become part of the commercial SNF inventory. Accordingly, the table identifies the number of canisters containing immobilized plutonium and high-level radioactive waste, and it counts the spent mixed oxide fuel as part of the inventory of commercial SNF.
Materials intended for geologic disposal