CE Seminar: Overview of Deep Geologic Waste Disposal Concepts and associated R&D Programs in Underground Research Laboratories in Switzerland

Speaker: Rainer Senger, Ph.D.

The National Cooperative for the Disposal of Radioactive Waste (NAGRA) has proposed a deep clay formation (Opalinus Clay) as possible host rock for a repository for low and intermediate-level waste (L/ILW) and spent fuel, high-level waste (SF/HLW). The Opalinus Clay is characterized by a low permeability and is, therefore, an excellent barrier against radionuclide transport. However, the accumulation of waste generated gas in the underground repository and migration through the engineered barrier system (EBS) and into the host rock is a critical component within the safety assessment of the proposed deep repositories in low-permeability formations. Nagra has developed a comprehensive program to characterize gas flow in low permeability formations. This includes laboratory programs for characterization of hydraulic and geomechanical properties of the clay and full-scale experiments at the Underground Research Laboratories (URL) in Switzerland – the Mont Terri URL and the Grimsel Test Site (GTS). The presentation will provide an overview of the deep repository concept and describes selected field experiments and numerical analyses associated with gas migration through clay, which have been conducted in collaboration with other agencies and international research organizations.

Bio:
Rainer Senger’s professional experience encompasses water-resources investigations, reservoir characterization studies, and site characterization and performance assessment of potential waste sites in the US, Canada, Switzerland, France, Israel, and Japan. He has also been involved in water resources investigations and responsible for developing groundwater availability models for several of the major aquifers in Texas. He has performed various deterministic and probabilistic assessment studies and has been involved in a variety of investigations for hydrogeological characterization and geosystems modeling of potential nuclear waste repository sites. In the area of site characterization, Rainer specializes in two-phase flow phenomena associated with migration of waste-generated gas from a potential waste repository, which includes coupled two-phase hydromechanical processes.
Education:
Ph.D. Geology, The University of Texas at Austin, 1989
M.A. Geology, The University of Texas at Austin, 1983
B.A. Geology, University of Karlsruhe, Germany, 1979