Status of German R and D on vitrified high-level waste and spent fuel disposal safety

In Germany, like in most other nuclear energy producing countries, long-term protection of public health and environment from highly radioactive wastes shall be guaranteed by isolation from the biosphere in suitable geological formations for a period long enough to prevent unacceptable levels of exposure of coming generations. This objective shall be achieved by a totally passive repository system of in part redundant engineered and natural barriers ensuring limited groundwater access to the radioactive substances, their long-term containment in waste packages and retardation of transport of radionuclides to the biosphere. The appropriateness of a selected disposal strategy must be demonstrated by site specific safety analyses, both for the operating phase of the repository and the long-term performance. The current state in the development of disposal technologies for heat generating waste in salt formation is described, together with the state of the art in long-term safety research, considering scenario development, performance assessments of individual barriers and overall safety assessment.