In Situ Investigations on the Impact of Heat Production and Gamma Radiation with Regard to High-Level Radioactive Waste Disposal in Rock Salt Formations

Deep geological formations, especially rock salt formations, are considered worldwide as suitable media for the final disposal of radioactive high-level waste (HLW). In the Federal Republic of Germany, the Institut für Tieflagerung of the Gesellschaft für Strahlen- und Umweltforschung mbH München operates the Asse Salt Mine as a pilot facility for testing the behavior of an underground nuclear waste repository. The tests are performed using heat and radiation sources to simulate disposed HLW canisters. The measured data obtained since 1965 show that the thermomechanical response of the salt formation and the physical/chemical changes in the vicinity of disposal boreholes are not a serious concern and that their long-term consequences can be estimated based on theoretical considerations and in situ investigations.