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Demonstration that safety risks, environmental impacts, and nuclear materials accountancy are quantified and acceptable within regulatory limits.
The committee generally concurs that meeting these criteria would provide DOE with sufficient information for decision making on the success of the 1999 EBR-II demonstration. However, some clarification of the criteria appears to be necessary. While the above criteria define general objectives, further clarification and well-articulated definitions may provide a stronger basis for ANL to demonstrate the effectiveness of electrometallurgical technology in treating spent fuel. For example, it is not clear what “significant deviations” means in the second criterion. Further, in the third criterion, how will “dependable” and “predictable” be defined? In the fourth criterion, who will determine acceptability in the areas mentioned? Before the demonstration is completed, DOE should establish criteria for success in the demonstration phase to allow evaluation of the electrometullurgical technology for further use. In 1999, ANL's achievements should clearly prove its competence to complete the processing of the remaining EBR-II spent nuclear fuel and provide DOE with confidence that the electrometallurgical technology will be a viable option for processing other DOE spent fuel.
The committee acknowledges that there must be a measure of subjectivity in deciding whether the criteria for success have been met, especially in an R&D program, and that criteria should not be too prescriptive. Nonetheless, there are several possible ways to define better the process for establishing success. To better define the goals in specific technical areas, ANL may consider, for example, involving external technical experts.
The current plan for application of the electrometallurgical technology to EBR II fuel is limited by restrictions on the amount of fuel that can be processed as set by the current EA. If the demonstration is successful, it would seem reasonable that the remaining EBR-II spent fuel would be treated by this technology. Processing of the remaining EBR-II spent fuel would require preparation of an EA plan within the next 2 years and its approval prior to further, and possibly expanded, utilization of the electrometallurgical technology. A new EA will be required to go beyond the currently approved amount of fuel. DOE should begin plans for such an EA now so that its preparation does not become a major delay, if the current project is successful. Alternatively, if the demonstration does not meet the criteria satisfactorily, other technologies will be required for treatment of the remaining EBR-II spent fuel.
Electrometallurgical Techniques for Treatment of Other DOE Spent Fuels
Electrometallurgical technology has been proposed as a process having the potential to treat successfully other DOE spent fuels. Among the earlier incentives to proceed with R&D on the electrometallurgical technology was its potential for handling a variety of different spent fuels, such as N-
reactor fuel from Hanford, Molten Salt Reactor Experiment (MSRE) residues, and Savannah River Site fuels. In its 1996 report, the committee recommended that “upon satisfactory completion of the demonstration with EBR-II fuel, the electrometallurgical technique should be evaluated in the broader context of alternative technologies for processing spent nuclear fuel” (NRC, 1996a, p. 2).
The major DOE spent fuel type is the N-reactor fuel at the Hanford site, which makes up nearly 80 percent of the DOE spent fuel inventory. The deteriorated condition of part of this fuel necessitates reduction of uranium oxide to the metal before its treatment using the basic electrometallurgical process. The ANL ancillary oxide reduction process using lithium metal must be demonstrated before the electrometallurgical process can be considered for use with this N-reactor fuel. When the requisite ancillary processes have been demonstrated, DOE should consider the electrometallurgical process in context with other competing processes for dealing with the DOE spent fuel problem. These competing processes include aqueous processes as well as long-term storage, which is planned and has been partially implemented for use with spent fuel at some DOE sites.
The committee continues to believe that successful demonstration of the electrometallurgical process for treating EBR-II fuel is essential to support development of applications of this technique to other DOE spent fuels. If this technology is to be considered by DOE for treatment of other reactor spent fuel, DOE should evaluate the upcoming results of the spent fuel treatment demonstration and initiate planning for the post-1999 period. DOE should begin to consider the criteria for success in the demonstration and the spent fuel to which the technology would be most applicable and to determine the R&D data and “hot” cell demonstration requirements for reaching a decision based on technological and economic considerations. This process should be initiated soon if DOE is to utilize the results of the 1999 demonstration effectively and if this technology is to be employed in the DOE-EM program. The committee wishes to restate its position that ANL, upon meeting the appropriate criteria for success in processing EBR-II driver fuel and blanket assemblies, should successfully demonstrate the processes ancillary to the central electrometallurgical process itself, for example, lithium reduction of oxide fuels, before the process can be considered seriously for use with other DOE spent fuel.
It appears highly unlikely that electrometallurgical techniques will be applied to the treatment of MSRE salts from Oak Ridge National Laboratory (NRC, 1997b). R&D dealing with extraction of zirconium and uranium may, however, have applications to spent fuels other than MSRE residues such as N-reactor fuel.
ANL's research efforts have involved the investigation of electrometallurgical technology for non-EBR-II fuels such as the N-reactor fuel. However, the DOE-EM may proceed with plans for the N-reactor fuel that do not include the use of electrometallurgical technology. Since the current approach of DOE-EM is to develop project plans for implementation within the next 10 years, the offices of Nuclear Energy (NE) and Environmental Management (EM) should maintain close contact to ensure proper coordination of their activities.
