Electroweak measurements in electron–positron collisions at w-boson-pair energies at lep

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INTERNATIONAL ATOMIC ENERGY AGENCY in co-operation with THE UNITED STATES ATOMIC ENERGY COMMISSION SYMPOSIUM ON ENVIRONMENTAL ASPECTS OF NUCLEAR POWER STATIONS MASTER IAEA-SM-1U6/23 STATUS OP SOLIDIFICATION AND DISPOSAL OP HIGHLY RADIOACTIVE LIQUID WASTES

ABSTRACT Solidification qf highly radioactive liquid wastes from reprocessing of spent nuclear fuels will soon be required in .the USA for additional improvement in safety during interim storage, during transportation to final disposal, and during final disposal at a. Federal repository. During the past 1? years, major research and development has been carried out to develop four basic processes for converting the high level liquid wastes to encapsulated solids. These processes are: spray solidification, pot calcination, phosphate glass solidification, and fluidized bed calcination. All processes are being demonstrated on an engineering-scale with radioactive wastes. In all four processes, the waste is heated to bOO °C to 1200 °C to drive off essentially all of the volatile constituents, leaving a solid or a melt that will cool to* a solid. Disposal of these radioactive wastes requires isolation from the biological environment for hundreds of thousands of years. The longevity of the hazard implies that the disposal system should be capable of providing this isolation without surveillance. ,After considerable study, natural salt deposits were concluded to be the most promising disposal locations Xn the USA for meeting these criteria. A concept for a facility to-dispose of containers of solidified highly radioactive vaste in a salt mine has-been investigated in an experiment in a salt mine. The overall disposal concept, as well as equipment requirements and handling techniques, were demonstrated. The US-AEC has proposed that all solidified highly radioactive vaste from nuclear power fuels be shipped to Federally owned repositories. Studies are currently in progress on the detailed design and cost estimates for such a first demonstration disposal facility to be located in a salt nine in the central area of the USA. The cost of high level waste management involving solidification in combinations with interim liquid storage, interim solid storage, transportation to final disposal, and disposal in a salt mine has been estimated to be about 35 to 50 mlls/MW hr e -or only slightly higher than the cost range for perpetual liquid storage