An Assessment of the Results of the Direct Disposal Project by the Federal Ministry for the Environment, Nature Conservation, and Nuclear Safety

Abstract

The completion of the direct disposal of spent fuel project and thus the implementation of technical developments in the field of direct disposal are within reach. Politically, these developments are reflected in the 7th amendment of the Atomic Energy Act (the so-called Artikelgesetz), which gives safe disposal of spent-fuel elements the same level of priority as safe reprocessing.Since the 1960s, the Federal Republic of Germany pursued the concept of nonretrievable final disposal of radioactive waste in deep geological formations. The results of the direct disposal project show that there are no substantial changes required for this concept. Within the framework of the project, it was demonstrated that the radiological and mining-related safety objectives of final disposal in a mine can be realized. With the termination of the basic activities in the direct disposal project, specific questions about the feasibility of technical implementation were tackled in a comprehensive manner. However, this does not mean that all issues relating to direct disposal have already been resolved, citing for example the verification of long-term safety based on site-specific data with consideration of geochemical processes and the actual planning of emplacement areas for different types of waste (spent fuel, vitrified high-level waste, medium-activity waste, etc.). One topic area for further research and development relates to questions of gas generation and its control. Increased knowledge of the material behavior of rock salt and of crushed salt—as used for backfilling—is prerequisite for a site-specific assessment of geology and the long-term safety.