Overview of key experiments on repository characterization in the Mont Terri Rock Laboratory

Abstract

Abstract Repositories for radioactive waste are designed as disposal systems that perform a number of functions relevant to long-term safety and security, including (1) isolation of waste from the human environment, (2) long-term confinement and radioactive decay within the disposal system and (3) attenuation of radionuclide releases to the environment. The generic rock laboratory at Mont Terri plays an important role in the characterization of such repositories. The experimental results gained in this underground facility are used, together with information from natural analogues, deep drilling programmes and modelling, to assess the evolution and performance of a repository. A time scale for processes affecting repository performance is outlined. A transient phase in the first 10–20 ka is followed by an equilibrium phase. Key experiments cover processes observed over relevant time scales, feasibility experiments and experiments focusing on long-term process understanding. The last can only be partly investigated over realistic time scales in direct experiments because of the long time frame required. Key experiments are briefly outlined and key references are provided.