Non-proliferation Aspects of Commercial Nuclear Fuel Cycle

In the international non-proliferation regime of concern, the denatured uranium (i.e., low enrichments in 235U or 233U) fuel cycles should be assessed in terms of proliferation criteria. The study attempts to establish a technical basis for a comparative assessment of the proliferation potential among the denatured uranium, the plutonium-uranium, and the breeder fuel cycles. The international commercial fuel cycles were analyzed within the context of current technology for the potential to: divert and upgrade the quality of nuclear material via the construction and operation of clandestine-scale reprocessing facilities and lowtechnology electromagnetic enrichment facilities, such as calutrons. Eleven fuel cycles were analyzed to determine the number of calutron base-feed units (kg of heavy metal) contained in typical fuel assemblies for each of the cycles to produce a significant quantity of high enriched uranium (HEU) material within limited time periods. The study indicates that, for calutron specifications within current technology, the level of effort to enrich 3% 235U/238U to HEU fuel is a factor of 20 lower than the two-stage process with natural uranium feed; 16 to 20 calutrons, total uranium feed requirements of 3800 kg, and 6 to 8 fuel assemblies are needed to produce a significant quantity of HEU in one year of operation. Consequently, non-proliferation concerns should be emphasized at the front-end of the fuel cycles involving uranium as well as at the back-end involving plutonium. The systems analysis approach to identify potential diversion scenarios should be supported and implemented by safeguards and non-proliferation agencies.