Abstract. The site selection procedure for a high-level radioactive waste repository in Germany is based on the Repository Site Selection Act (StandAG, 2017), which comprises three phases. In phase 2, the Federal Company for Radioactive Waste Disposal (BGE) will conduct surface exploration. Based on the exploratory findings, the further developed preliminary safety analyses, the common requirements and criteria, and socioeconomic potential analyses will be applied feeding into proposed sites for underground exploration. Commissioned by the BGE, the Federal Institute for Geosciences and Natural
Resources (BGR) contributes to this procedure with the projects “GeoMePS”
and “ZuBeMErk”, which compile and assess geoscientific and geophysical
methods and programs for surface exploration. Their common goal is to develop recommendations for surface exploration of siting regions. For this purpose, the BGR has developed a systematic approach that includes (1) deducing 186 exploration targets (Kneuker, 2020) based on the requirements defined by StandAG, (2) compilation of geoscientific and geophysical exploration methods in a database structure, and (3) analysis of case studies of national and international exploration programs for high-level radioactive waste disposal. During step (2) the BGR developed the database “GeM-DB” which utilizes MS
SQL Server 2017 and PHP scripts for a browser-based interface (Beilecke, 2021). Both lead to a highly customizable, user-friendly database enabling further adaptations, expansions and analyses of the contents. Merging the knowledge of about 100 BGR experts, the database currently comprises approx. 140 geoscientific and geophysical exploration methods, including basic information and essential metadata to evaluate the general applicability of the methods for surface exploration of the three defined host rocks (crystalline rock, claystone, rock salt). Additionally, the methods are rated according to their suitability for the previously defined exploration targets. An example for a method selection, which is suitable to target fault zones (exclusion criterion 2, StandAG) is given in Fig. 1. In step (3) the BGR screens national and international waste disposal programs exploring for crystalline rock, claystone, and rock salt and feeds the obtained information back into “GeM-DB”. The entire systematic approach of the projects “GeoMePS” and “ZuBeMErk” aims to develop recommendations for a non-destructive and minimally invasive surface exploration program of siting regions in Germany, regarding the lithological, structural, mechanical, and hydrogeological characterization of the different host rock formations.
In Situ Experiments for the Development of High-level Radioactive Waste Disposal Techniques at Underground Research Laboratories in Foreign Countries
