Disposal systems / components

Our research for nuclear waste disposal deals with various safety issues relevant in the pre-disposal phase, during waste emplacement and in the post-closure phase of a deep-geological repository. Research activities focus on long-term safety of multi-barrier systems for disposal of nuclear waste.

Applied and fundamental studies are performed on subsystems (i.e. waste matrices, container materials, geo-engineered and geological barriers) of various repository concepts in argillaceous, crystalline and saline host rocks. These activities comprise a wide span of experimental and theoretical investigations concerning the behavior of low to high level waste forms under repository conditions, radionuclide release from these waste forms, development of geochemical milieu in the near-field of a repository, alteration of container materials and geo-engineered barriers, radionuclide retention by near-field components of the repository and the adjacent geological barrier.

Studies are performed to assess the stability of cemented (low / medium level) waste forms as well as highly active waste components such as spent nuclear fuel, HLW glass, activated steel and fuel rod claddings. The latter is of relevance both to final disposal and to prolonged interim storage of irradiated nuclear fuel elements.
Furthermore, experiments with radiation sources and numerical simulation techniques are applied for assessing radiation fields in the vicinity of containers with high level wastes, the respective ambient dose and shielding requirements, as well as the individual dosimetry of personnel during storage in surface facilities and emplacement of the waste forms in deep geological repositories.

Scientific achievements of our investigations are applied to safety analyses, safety and disposal concept developments of current and future disposal projects as well as contributions to public information with respect to comparison of repository concepts in various host rocks.