Two Decades of Evolution of Hardrock Seismic Imaging Methods Applied to Nuclear Waste Disposal in Finland

H004 TWO DECADES OF EVOLUTION OF HARDROCK SEISMIC IMAGING METHODS APPLIED TO NUCLEAR WASTE DISPOSAL IN FINLAND ABSTRACT 1 The Finnish Site Investigation Programme for the Final Disposal of Spent Nuclear Fuel started over two decades ago. The Eurajoki-Olkiluoto was selected for building the planned repository. Based on the large number of surveys performed and the ample direct and indirect verifications the multiazimuth multi-offset VSP is considered an effective method for determining the positions and orientations of fracture zones in crystalline rock. This has been continuously developed and used extensively for general to detailed hardrock site characterization in Finland. BACKGROUND