Characterization and 3D visualization of underground research facility for deep geological repository experiments: A case study of underground research facility Bukov, Czech Republic

Abstract

Abstract The recently opened Bukov underground research facility is used by the Czech national authority for radioactive waste repository for underground research and safety assessment purposes as part of the Czech deep geological repository (DGR) development programme. The laboratory, which is both site-specific and generic at the same time, is located at a depth of 550\u202fm below ground level in the former Rožna uranium mine in the southeast of the Czech Republic in crystalline rocks of the Bohemian Massif. During the laboratory construction, a multidisciplinary approach was used in order to document and visualize the environment for the following experimental programme. The obtained data are important for understanding the geological environment and the rock characteristics of the Bohemian Massif in the process of deep repository planning and siting. The multidisciplinary approach included petrology, structural geology, geochemistry, geochronology, geotechnical parameters and excavation damage zone description, as well as 3D visualization of the rock environment and laboratory itself. New field observations reveal the Cambrian–Ordovician volcano-sedimentary origin of the studied rocks that have been affected by two-phase reworking during the Variscan orogeny. The rock mass is of high to very high strength and low permeability and the rock mass properties are mainly influenced by tectonic structures. Above all, the presented multidisciplinary approach enables unified and comparable evaluation of such facilities as well as the potential locations of the future DGR.