Use of highly-enriched uranium in Russian reactors

Use of highly-enriched uranium (HEU) in reactor fuel presents one of the most serious dangers from the point of view of diversion or loss of weapon-grade material. Russia is one of the countries that actively use HEU in their research, transport, and production reactors. As a participant of the Global Threat Reduction Initiative (GTRI), Russia has been involved in the process of reducing the use of HEU in Soviet-designed research reactors outside of Russia by bringing fresh and spent HEU fuel into Russia and converting the research reactors to LEU fuel. The process of reducing the amount of HEU in use inside Russia, however, has been almost completely ignored. Russia only recently committed to begin feasibility studies to convert some of its research reactors and has no plans to reduce use of HEU in its civilian or military transport reactors or tritium/isotope production reactors. Some of the reactors that use HEU fuel are outside of the scope of the GTRI program. As a result, substantial amounts of HEU continue to circulate through enrichment and/or down- blending, fuel fabrication, use in reactors, and reprocessing. This paper presents an analysis of the flows of HEU related to reactor operations and suggests ways that would allow reducing the risks associated with circulation of HEU in Russia.