Swiss field investigations for radioactive waste repositories

The Swiss National Cooperative for the Storage of Radioactive Waste, Nagra, plans two types of repositories, one for high-level waste and possibly certain alpha-containing intermediate-level waste (Type C repository) and one for low-and intermediate-level wastes (Type B repository). This paper discusses how for the Type C repository, a regional field investigation program was started in 1980 with geophysical, hydrogeological and neotectonic investigations and a deep drilling program, in which to date 6 deep boreholes of a total length of more than 10 km have been drilled and investigated. For the Type B repository, preliminary field investigations have been carried out at 20 potential sites, and a detailed site investigation program at 3 sites is ready to start as soon as the needed permits from the authorities are granted. At Grimsel, and underground test facility (FLG) has been excavated, and several test programs are in progress