from processing the EBR-II fuel. The program has developed leak-tight containers to handle the zeolite containing less than 0.1 percent water.

Stephen G. Johnson, ANL-W, directed attention toward measures to define the quality of the waste products. A battery of tests will define the acceptable envelope for operational functions and materials processing parameters. Examples of tests are electron microscopy and x-ray spectroscopy to reveal microstructure and the location of radionuclides.

Denis M. Strachan, ANL-E, continued the discussion of waste form qualification by describing the hydration and leach tests to which the waste forms would be subjected. The demonstration program will use the experience of certifying wastes from the Defense Waste Processing Facility and the West Valley Plant. So the ANL qualification program will develop documents on waste form acceptance, product specifications, compliance plans, and the qualification report. The DOE responsible organization will write the waste form acceptance document with review and concurrence by the HLW program. ANL will develop the compliance plan that includes the product specifications and will publish the qualification report that presents the test data.

Sean McDeavitt, ANL-W, characterized the metal waste form by metallurgical description of the iron solution metal phase, the intermetallic, Zr(Fe, Cr, Ni) 2+x, phase, and the small-volume (<10 percent) Zr6Fe23-type phase. Qualification tests of the metal waste form include accelerated tests, service condition tests, mechanical testing, and thermophysical properties measurements.

Dennis D. Kaiser, Jr., ANL-W, focused on the production of the metal waste forms that would be tested as part of the treatment demonstration. The production starts with the characterization of irradiated cladding hulls and concludes with the casting of the metal waste ingots. Incomplete melting of the zirconium hulls is caused by heat loss from the high-temperature furnace. Also, the addition of nonirradiated zirconium and stainless steel seems to help initiate melting. Characterization of the irradiated cladding hulls is complete. The furnace will be modified to generate mid-sized metal waste ingots.

Stephen G. Johnson, ANL-W, addressed the committee again, this time on the metal waste form testing program. Samples for the test program bracketed the compositions expected from the treatment demonstration. In order to simulate a worst case scenario, metals containing technetium were leached in deionized water heated to 90 ºC. Leached technitium was determined using liquid scintillation. Measured reaction rates were used with reasonable assumptions to extrapolate that a thickness of 80 × 10−6meters or 3 thousandths of an inch would be reacted in 1,000 years under these extreme corrosion conditions. This was a scoping calculation, with very rapid rates of decomposition initially, mostly in the first month. This rate is not expected over time, certainly not under standard temperature and moisture.

Shelly X. Li, ANL-W, focused on the electrorefiner by discussing throughput as a function of the geometry of the anodes and cathodes, and the current and voltage histories during refiner operation. Preparations for the high-throughput modifications to the Mark-IV and the newly designed Mark-V refiners are being coordinated between ANL-W and ANL-E. It is difficult to separate uranium and zirconium even though their electrochemical potentials differ by 0.4 volts. From June 1996 through October 1997, 144 kilograms of spent fuel have been processed. ANL-E is producing UCl3 that will be used as an oxidant that is introduced into the ER.

Eddie C. Gay, ANL-E, designs the electrodes for the HTER. The HTER is a refiner operated at ANL-E to support design of the Mark-V refiner. Gay specified the features needed for high throughput including

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