PREPARING FOR POTENTIAL CHANGES IN NATIONAL NUCLEAR WASTE DISPOSAL POLICY: APPROACHES BY THE NUCLEAR REGULATORY COMMISSION STAFF

Staff of the U.S. Nuclear Regulatory Commission (NRC) is preparing for the agency’s potential regulatory role in future national policy for geologic disposal of high-level radioactive waste (HLW) and spent nuclear fuel (SNF). These preparations focus on maintaining and enhancing staff capabilities to assess and review technical issues on the performance of potential HLW and SNF disposal facilities. Current staff efforts include developing performance assessment tools, engaging international counterparts on regulatory and technical approaches, and investigating specific technical areas. These works are supported by the Center for Nuclear Waste Regulatory Analyses (CNWRA), NRC’s federally-funded research and development center. NRC and CNWRA staff have developed a scoping-level performance assessment model to examine aspects of potential, geologic disposal scenarios. The model compares different waste inventories, waste forms, and engineered barriers, in different generic host rocks and flow and transport regimes. Preliminary results have provided improved understanding of the relative contribution of different features in different settings. Staff’s efforts in international engagement have led to several collaborative research projects, including renewed NRC participation in the DECOVALEX project. This international project aims to improve understanding of coupled thermal-hydrological-mechanical-chemical processes in potential geologic disposal facilities. NRC and CNWRA staff also continue to identify and analyze key technical areas related to geologic disposal, including common buffer materials and their performance metrics, fuel types and degradation in anoxic environments, and canister performance and sensitivity of radionuclide transport in various environmental conditions.

National policy in the United States for management and disposal of HLW and SNF continues to evolve. Future changes in NRC regulations and guidance may be needed as the policy and legal frameworks become more clearly defined.

The NRC staff views expressed herein are preliminary and do not constitute a final judgment or determination of the matters addressed or of the acceptability of a license application for a geologic repository at Yucca Mountain or for any existing or future licensing activities.