Effects of gamma Irradiation on Leaching of /sup 137/Cs from Organic Matrix Waste Forms

摘要

The effects of gamma -irradiation on the leaching behaviour of /sup 137/Cs in organic matrix wasteforms has been studied. The matrix materials used include epoxide, polyester and vinyl ester thermosetting resins and bitumen. Leaching of /sup 137/Cs in such matrices can be described by models, based on diffusion, which take into consideration such factors as non-representative surface layers, finite sample size, and sorption effects. In many cases, the changes observed on irradiation arise from modification of the sorptive capacity of the wasteform for /sup 137/Cs, producing changes in the experimentally observed diffusion coefficients. In samples containing wet wastes, enhanced leaching in the first few days is observed after irradiation. This arises from loss of water from the sample surfaces during irradiation producing an enhanced concentration of the radionuclide in the surface. (ERA citation 13:021049)