Recent developments in the design of a HLW repository in Spain

The Spanish policy stated in the General Radioactive Waste Plan contemplates deep geological disposal according to direct disposal strategy. Since the selection of the host rock in Spain is not expected until the next decade, a generic analysis has been performed by the Empresa Nacional de Residuos Radiactivos, S.A. (ENRESA) with the objective of defining a unified disposal concept which can be easily adapted to any of the three host rock options currently being considered (clay, granite and salt). This will help to optimize the research and development activities which need to be undertaken to provide support to the performance assessment studies of the repository system. This paper summarizes the rationale behind this strategy, describes the approaches used for the definition of common basic design items from the repositories in clay, granite and salt and, as a consequence of this process of convergence, presents a generic reference repository design which should facilitate the decision-making process until a host rock formation is finally selected