Geoscientific characterization of claystone as part of the German Repository Site Selection Act – “Methods and work status”

According to the Repository Site Selection Act (Standortauswahlgesetz – StandAG), the German Site Selection Procedure is an iterative process and consists of three phases with increasing levels of detail in which the assessed area is continuously reduced during the process. Starting with an empty, so-called “white map of Germany,” BGE (implementer of the German Site Selection Procedure) completed Step 1 of Phase I in September 2020 with the submission of the Sub-areas Interim Report (BGE 2020/88), where BGE identified 90 individual sub-areas (in claystone, rock salt, and crystalline rock).

In Step 2 of Phase I, BGE aims to localize siting regions within the 90 sub-areas by applying preliminary safety assessments and other scientific criteria. Within the preliminary safety assessments, subsurface data are interpreted and the results documented. The workflow comprises the detailed characterization and interpretation with a focus on the host rock formation that acts as the main geological barrier but also considers the surrounding rock formations.

Part I of this contribution describes important methods that are used to characterize and assess the claystone successions present in the different sub-areas.

BGE (2020/88): Sub-areas Interim Report pursuant to Section 13 StandAG. Bundesgesellschaft für Endlagerung mbH (BGE). Peine: Bundesgesellschaft für Endlagerung mbH (BGE). https://www.bge.de/fileadmin/user_upload/Standortsuche/Wesentliche_Unterlagen/Zwischenbericht_Teilgebiete/Zwischenbericht_Teilgebiete_-_Englische_Fassung_barrierefrei.pdf

StandAG: Standortauswahlgesetz vom 5. Mai 2017 (BGBl. I S. 1074), das zuletzt durch Artikel 8 des Gesetzes vom 22. März 2023 (BGBl. 2023 I Nr. 88) geändert worden ist.