Between 2019 and spring 2022, Nagra (the National Cooperative for the Disposal of Radioactive Waste) carried out geological investigations in order to further its knowledge of the substructure in potential regions for housing a deep geological repository. Under the Nuclear Energy Act, a licence has to be granted to carry out geological investigations. The Federal Department of the Environment, Transport, Energy and Communications (DETEC) granted a total of 22 licences for exploratory drilling up to 2021, of which Nagra carried out 9. In addition, there were a further 11 licences for quaternary drilling. The drilling provided Nagra with more precise information about the rock strata in the subsurface. This enabled Nagra to assess the geological situation with regard to the possible repository types. The drillings complemented findings from previous investigations. Nagra took its site selection decision in September 2022 on the basis of all the findings.
The SFOE was responsible for the licensing procedure in conjunction with the relevant federal and cantonal authorities. A separate licensing procedure was conducted for each site. All licence applications were publicised. People affected by planned explorations were able to lodge an appeal with the SFOE.