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The objective of the work was to evaluate the long-term capacity of sintered glass to retain high-level nuclear wastes (HLW) in near-repository conditions. We have studied the corrosion behavior of waste forms partially devitrified (43 vol.%) in different aqueous media. Devitrified samples were irradiated at doses (γ radiation from a Co 60 source) ranging from 1.4 × 106 Gy to 2.0 × 108 Gy, in order to study their aqueous corrosion resistance in simulated underground water. The results show little or no effect of irradiation on the density, microstructure and corrosion resistance. The global dissolution rate was almost constant around a value of 5×10−5 g. cm−2 d−1. Elemental dissolution rates were also unaffected by radiation.

The first aim of the work was to calculate, by means of the computer codes ORIGEN2. 1, ITS 3.0 and TRIM95, the beta/gamma cumulative dose and displacements produced by the fission products hold in the high level wastes (HLW) from reprocessed CANDU spent fuel, up to one million years, with a burnup of 7,000 MWd/tU and a cooling time of 20 years. Based on that results were calculated and graphically presented the mean electron energy (β−, internal conversion and Auger) and the cumulative beta events and ionization dose due to electrons, per metric ton of heavy metal and per cubic centimeter of the sintered HLW glass form, as a function of the time up to one million year.