(GRS 173) Experimental Investigations on the Backfill Behaviour in Disposal Drifts in Rock Salt (VVS-Project)

Johannes Droste, Hans-Karl Feddersen, Tilmann Rothfuchs

In the Federal Republic of Germany, two emplacement concepts have been developed for the disposal of heat generating waste from nuclear power plants. The drift emplacement concept comprises the direct disposal of spent fuel assemblies by packaging the fuel rods in self shielding Pollux casks which are emplaced in the drifts of a repository in rock salt. The remaining volume of the drifts will be backfilled with crushed salt immediately after the emplacement of the casks. The borehole emplacement concept provides the disposal of vitrified high-level waste in canisters which are stacked in vertical boreholes beneath repository drifts. The upper part of the boreholes and the annulus around the canisters will be backfilled with crushed salt.