Abstract: The disposal of spent fuel and high-level radioactive waste is a global challenge. Many countries with nuclear energy are working towards building a permanent geological repository, and the United States Department of Energy launched the Spent Fuel and Waste Science and Technology (SFWST) program to provide a technical basis for alternative disposal options across clay, crystalline, and salt rocks. The program emphasizes international cooperation as an effective strategy for sharing information and knowledge. The United States program established formal and informal cooperation partnerships with several international initiatives and institutions, focusing on collaborative research and development (R&D) activities in important areas such as engineered barrier integrity, near-field perturbations, radionuclide transport, performance assessment, and methods for characterization and monitoring of engineered and natural barriers.

This presentation provides an overview of R&D activities via international collaborations, with a focus on work conducted at underground research laboratories (URLs). URLs have been critical in advancing not only the R&D program but also the final licensing, construction, and optimization of the repository. The HotBENT field test at Grimsel Test Site in Switzerland is used as an example to illustrate how SFWST uses international collaboration to advance its R&D. 

Biography: Dr. Liange Zheng is a staff scientist and head of the Nuclear Energy and Waste Program at the Energy Geoscience Division at Lawrence Berkeley National Lab. His research interests are centered on numerical modeling of non-isothermal multiphase flow and reactive transport in porous media. His research work is mainly related to coupled thermal, hydrological, mechanical, and chemical (THMC) processes modeling for radioactive waste repositories and CO2 geological sequestration.  He holds a Ph.D. in Civil Engineering from the University of La Coruna, Spain, and majored in hydrogeology during his undergraduate study at Jilin University in China.