Nuclear Security Impacts of HALEU Fuels in Advanced Reactors

With the anticipated development and deployment of several advanced reactors designed to use High-Assay Low Enriched Uranium (HALEU) fuel, the demand and international usage of HALEU fuel is expected to significantly increase. HALEU is defined as material enriched between 5 and 20wt% 235U and Low Enriched Uranium (LEU) is material enriched to less than 5wt% 235U. It is important to understand any associated security concerns with the increased production and international usage of HALEU. The United States Nuclear Regulatory Commission classifies HALEU fuel facilities as Category II: moderate strategic significance, versus LEU fuel facilities, which are categorized as Category III: low strategic significance. This difference in designation corresponds to more restrictive security requirements for nuclear facilities producing and handling HALEU fuel. This report investigates the nuclear security impacts of increased use of HALEU and compares them to those of LEU. Specifically, consequences of facility sabotage and radiological sabotage were examined for steps in the nuclear fuel cycle, including enrichment, downblending, fuel fabrication, transport, reactor operations, and irradiated fuel storage and transportation.