A REGULATORY ANALYSIS OF INCIDENTAL WASTE

ABSTRACT * Spent nuclear fuel and vitrified high-level waste (HLW) have been selected as the main candidates for disposal at the proposed deep geologic repository at Yucca Mountain (YM), Nevada. The question remains: what should be done about the components, residuals, and side streams from reprocessing of spent nuclear fuel? In general, reprocessing involves dissolving spent nuclear fuel. Subsequent chemical processing can then be used for selective removal of fissile material for reuse and other needed isotopes. The associated waste stream is a solution of fission products and other radioactive elements. By definition, from the Nuclear Waste Policy Act of 1982, as amended, both the supernate and sludge resulting from reprocessing of spent nuclear fuel are classified as HLW. In other words, wastes from reprocessing are classified by source, and not by risk to human health or the environment. At the Department of Energy’s (DOE) Savannah River Site, the supernates and sludges from reprocessing, and from production of weapons-grade fissile material, are stored in 51 underground tanks until they can be separated and processed. The supernate is treated to remove fission products, and the remaining low-activity liquid is then made into saltstone and disposed of onsite. The removed fission products are combined with the HLW sludges and vitrified at the Defense Waste Processing Facility for eventual disposal at YM. Thus, the supernate stream, originally classified as HLW, is separated into an HLW fraction, and an incidental or low-level waste (LLW)