Presentation of the Grimsel Test Site

For the performance assessment of a HLW repository in a geological formation it is essential that the quality of the host rock is well known and its future behaviour is well understood. The relevant parameters have to be reliably quantified. Due to the need to forecast performance over very long time spans mostly new methods and technologies for site investigations have to be applied. In view of a possible HLW repository in the crystalline bedrock in northern Switzerland, NAGRA is not only participating in the international Stripa Project but has also established its own test site in an area where granitic rock of the desired qualities is easily accessible. At the Grimsel Test Site (GTS) in the Central Aare Massif a variety of large scale experiments is carried out in order to gain know-how and practical experience with in-situ tests. GTS is not a potential repository site. (orig.)