Methods for safety-related weighting and comparative assessment in the site selection process (MABeSt)

Abstract

Abstract. The Federal Office for the Safety of Nuclear Waste Management (BASE) supervises the site selection process in Germany and in particular has the task to review the proposals made by the implementer (Federal Company for Radioactive Waste Disposal, BGE) for determining the siting regions and sites in accordance with §§ 14, 16 and 18 of the German Repository Site Selection Act (StandAG). To determine the siting regions from the sub-areas and the sites from the siting regions, it is likely that safety-related weighting of the results from the application of the geoscientific weighting criteria (§ 24 StandAG) and the application of the preliminary safety investigations (§ 27 StandAG) are necessary. In order to be able to assess and evaluate the proposals of the BGE with respect to the methodological procedure for determining the siting regions and sites, the research project “Methods for safety-related weighting and comparative assessment in the site selection process” (MABeSt) was initiated by BASE. The objective of the research project was to research and explain the state of the art in science and technology (S&T) with respect to safety-oriented weighting and comparative assessment methods and their potential applicability for the selection of siting regions and sites in the site selection process. The status of S&T for safety-oriented weighting and comparative assessment methods was examined and evaluated with respect to site selection procedures for repositories in Germany and abroad (e.g. Switzerland) and also to methodological approaches from other topics (e.g. landfill site selection). The site selection process represents a multicriteria decision problem, which means that methods from the research field of decision theory appear to be suitable. In particular, methods from the multiattribute decision making/aid (MADM) category were identified as suitable and their potential applicability was examined and evaluated. Specific challenges (e.g. data uncertainties, different scales of evaluation criteria) for the relevant procedural steps of the site selection process were taken into account. We present the results and conclusions of the project MABeSt (funding code/4718F13001) carried out by GRS gGmbH and initiated and funded by BASE.