the present laboratory-scale (25g) samples will begin with operation of a 2.5 kg fluxing melter, first with simulated materials and subsequently with radioactive materials. Development of a continuous-feed melter for production will begin with conceptual design studies.
Qualification of the electrometallurgical treatment process wastes for repository disposal will be carried out in accordance with a Waste Form Qualification Plan to be issued early in FY1995. Performance testing of the two high-level waste forms will be conducted in compliance with the provisions of that plan, and will include characterization of physical and mechanical properties as well as resistance to leaching by groundwater. Radiolytic effects on the integrity of the waste forms will be examined as well.
Major milestones for this task for the period FY1995-FY1997 are as follows:
Major Milestones, FY-1995
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Issue waste form qualification plan (2/95)
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Establish mineral waste form characterization method (4/95)
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Issue waste form requirements and criteria document (6/95)
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Establish reference composition for TRU product form (7/95)
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Complete initial corrosion testing of reference metal waste form compositions (7/95) >
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Issue interim mineral waste form acceptance data package (9/95)
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Complete mechanical testing of reference metal waste form compositions (9/95)
Major Milestones, FY-1996
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Fabricate and test metal waste form samples from hot wastes (3/96)
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Fabricate and test mineral waste form from simulated sludge feed (4/96)
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Fabricate mineral waste form samples from FCF hot wastes (7/96)
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Fabricate and test hot specimens of TRU product form (8/96)
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Confirm radiation stability of mineral waste form (9/96)
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Issue performance and characterization tests document (9/96)
Major Milestones, FY-1997
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Issue criteria and selection methodology document (12/96)
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Complete mechanical characterization of full-scale cold waste forms (4/97)
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Fabricate and test full-scale hot metal waste form (7/97)
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Fabricate and test hot specimens from sludge process (9/97)
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Fabricate and test full-scale hot mineral waste form (9/97)
LONG-RANGE SCHEDULE
A top-level schedule for the development program, covering the period FY1995-FY2001, is shown in Figure 1. Included in the schedule is the treatment of EBR-II spent fuel, which will be carried out as part of the EBR-II shutdown operations. In addition to providing a large-scale demonstration of
the electrometallurgical treatment of sodium-bonded metallic fuel (demonstrating the applicability of the technique to Fermi-1 driver fuel and blankets), this activity will also provide valuable experience with process equipment systems and operating procedures.
The principal objective of the electrometallurgical treatment development program is clearly seen in Figure 1. The program is geared to the development and comprehensive demonstration of a technology that can be applied to the timely solution of a national problem, the disposal of DOE-owned spent nuclear fuel. The technology development and demonstration will be directed toward two fuel types, metal and oxide, that together comprise over 90% of the DOE spent nuclear fuel inventory, as well as to development of a special application (basin sludge recovery and treatment) that will ameliorate a potential environmental problem at the Hanford site. The timing of the development program is very demanding, directed toward completion of the work so that a meaningful base of experience is at hand by the end of FY1998 to permit a reasoned decision on the application of the electrometallurgical treatment technique to the treatment of DOE spent fuel. Argonne National Laboratory is not proposing the shipment of spent fuel inventories to any particular site for treatment, but instead proposes to support the implementation of the technology at the sites where the spent fuel is now stored. Because the facility requirements and equipment costs for such installations are expected to be quite modest, possibly permitting the use of existing facilities in some cases, the electrometallurgical treatment technique is likely to represent the low-cost alternative for many of the spent fuel categories.
This program plan does not include provisions for development of head-end processes that would facilitate the electrometallurgical treatment of fuel types other than metal and oxide. Among the fuel types not covered are two highly-enriched fuels, Naval reactor fuel and graphite fuels from the Fort St. Vrain and Peachbottom reactors. The quantities of these fuels are significant, and the high level of 235U enrichment implies that treatment will be necessary before disposal. However, these are very stable fuels and they are likely to withstand extended interim dry storage without significant degradation. Hence, a decision on the method of treatment of Naval reactor and graphite fuels can be deferred until certain institutional and technological issues (including the development of the electrometallurgical treatment technology) can be resolved.