Netherlands Approach for Assessing the Performance and the Long-Term Safety Aspects of a High-Level Waste Repository to Be Mined in a Medium-Sized Salt Dome

摘要

This report describes the performance assessment work that is being carried out under contract to the European Commission in order to evaluate the isolation capability of a salt dome that is to be used for the disposal of high-level waste. The work is based on the assumption that the normal evolution scenario for radionuclide release from a repository that is mined in a medium size salt dome will be a continuous subrosion of the salt dome. This report is a compilation of the three progress reports published on this subject. It reviews the general regional setting of The Netherlands' reference salt dome and the consideration that led to the new approach in geohydrological modelling. This modelling is based on the assumptions thet the subrosion started 1.2 x 10/sup 6/ years ago and that the future climatic changes remain limited to a continuing Quaternary type of development in average temperatures. It describes the composition of the model used for calculating the subrosion rate with the use of a modified version of the SWIP-2-computer code. And it gives the results of the calculations on both the flank and top subrosion. The main conclusion is that even under very conservative assumptions the calculated subrosion rates are so small that the isolation capability of a salt dome with an adequately designed repository is at least in the order of a million of years. (ERA citation 13:024151)