Geological disposal of fusion wastes

The concepts developed in Sweden for the management of radioactive wastes from fission power also form a natural basis for an approach to the management of fusion wastes. Against this background, work on the management of fusion wastes in the Swedish fusion research programme as associated to the European Fusion Technology Programme was started by STUDSVIK in 1983. A tentative strategy for the application of various disposal routes was worked out. In coordination with efforts by other parties it was decided to focus the Swedish work on shallow and deep geological disposal of fusion wastes with the assessment of safety and costs for these disposal routes as the primary objective. For the safety assessment, data published on the sorption and migration in the geosphere of some nuclides of interest were found to be scarce or missing. Sorption experiments have thus been performed to determine distribution coefficients for molybdenum, lead and inorganic carbon in sorption on rocks from artificial groundwater and from water equilibrated with concrete. The computer code BIOPATH has been used for the calculation of the turnover of nuclides in the biosphere and the resulting doses to man. Results from the sorption experiments and from a preliminary safety assessment are presented in the paper. The classification and characterization of waste from the operation of the Tokamak reactors NET IIIA and FCTR have been used together with specific disposal costs for the various wastes in the Swedish nuclear programme to estimate disposal costs for fusion wastes. Preliminary results of these estimates are given. (author). 15 refs, 2 figs, 6 tabs