Geochemical, Petrophysical and Rock Mechanical Characterization of Crystalline Rocks in Germany for High-level Radioactive Waste Disposal – First Results of the AMPEDEK Project

The safe disposal of radioactive waste is a critical and frequently discussed topic in society. The Bundesgesellschaft für Endlagerung (BGE) was assigned with the selection of a suitable site for the disposal of high-level radioactive waste in Germany and, in the first phase of the selection procedure, has defined various selection criteria and sub-areas, seven of which cover the crystalline basement in Germany. For most of these sub-areas, little or no information is available on the crystalline host rocks and their properties, which would allow a narrowing of the site selection and identification of a suitable repository. Therefore, the AMPEDEK project establishes a reference database for the characterization of crystalline rocks in Germany. For this purpose, the database will contain information on the mineralogical, geochemical, petrophysical, and rock mechanical properties of predominantly igneous and metamorphic rocks of the Variscan basement. In the first phase, existing data from the literature or state geological offices were compiled and the structure of the database was established. In the second phase, ~500 drill cores and rock samples from quarries were analyzed in the laboratory to close existing data gaps. The goal was to sample as many different lithologies as possible to create a database that covers the majority of the relevant areas. The database currently contains ~8600 data points from 8 states and will be used to select smaller areas for Phase 2 of the site selection process and thus for detailed surface geological exploration campaigns.