A number of countries have operated underground research laboratories (URLs) in different types of potential host rocks to support the development of deep geologic repositories for the disposal of radioactive waste. URLs enable research and development (R&D) activities to be conducted under subsurface conditions and at scales relevant to repository environments.
Since 2012, the U.S. Department of Energy (DOE) and its national laboratories have collaborated in research conducted in several URLs located in Europe and Asia. Jens Birkholzer, Berkeley Lab Senior Scientist and Energy Geosciences Division Director, has served as DOE’s technical lead for these international collaborations since 2014. Under his guidance, international collaborations have grown into an important component of DOE’s geologic disposal research program.
To review the technical and scientific validity of DOE R&D activities related to URLs, and to elicit information on international URL R&D programs useful to DOE’s implementation of the R&D activities, the U.S. Nuclear Waste Technical Review Board held a workshop on “Recent Advances in Repository Science and Operations from International Underground Research Laboratory Collaborations” in Burlingame, California, on April 24 and 25, 2019. During the workshop, four speakers from other countries—three from those with operating URLs (France, Sweden, and Switzerland) and one from a country without an URL (United Kingdom)—described the integration and contribution of URL science to their respective country’s radioactive waste management program.
DOE-funded principal investigators from the national laboratories gave technical presentations on DOE’s URL-related R&D activities, focusing on near-field perturbation; engineered barrier integrity; hydrologic flow and radionuclide transport; and geologic disposal safety assessment. In addition to Jens Birkholzer, Berkeley Lab was represented by scientific presentations from Jonny Rutqvist and Liange Zheng. Findings from the workshop were then analyzed and synthesized in a recently published report by the NWTRB entitled: Filling the Gaps: The Critical Role of Underground Research Laboratories in the U.S. Department of Energy Geologic Disposal Research and Development Program.
The Board’s summary was very supportive of DOE’s strategic decision to emphasize international collaboration in disposal science, with emphasis on participation in URL-related studies. According to the Board, DOE participation in URL-related international research greatly benefits the U.S. geologic disposal R&D program by furthering its understanding of generic and site-specific disposal issues relevant to alternative repository host rocks and environments. DOE-funded R&D activities also are benefiting the URL-related research of other countries, especially in the area of complex analytical and numerical model/software development.