(GRS 201) CROP - Cluster Repository Project

Tilmann Rothfuchs, Johannes Droste, Horst-Jürgen Herbert, Klaus-Peter Kröhn, Klaus Wieczorek, Chunlinag Zhang

Several underground research and development projects, which deal with disposal of radioactive waste in crystalline rock, salt and clay formations, have been supported by the European Commission. By constituting a forum (the Cluster Repository Project(CROP) for synthesising construction experience and results from testing engineered barrier systems (EBS) in underground laboratories, and correlation of theoretical predictions with the outcome of performed experiments) a basis was to be worked outfor the assessment of the status achieved in Underground Research Laboratories (URL) with regard to future design and construction as well as technical/economical improvement of concepts of future European repositories for highly radioactive waste. The focus of the CROP project was on the behaviour of and processes in EBS, primarily buffer and backfill materials used for embedding waste containers and on backfill materials in boreholes, tunnels and shafts for sealing the repository from thebiosphere.