DOE OSTI2012
Although this paper provides a short history and discussion of some of the important issues pertaining to WG-MOX, the primary focus of the paper is to provide a useful bibliography of resources pertaining to weapons-grade MOX fuel use in LWRs. Therefore, not all aspects of MOX use were reviewed in this paper. Sandia National Laboratory and other investigators have performed significant work in the United States on severe accident source terms for MOX fuel cycles in comparison with LEU fuel cycles. Sandia’s source term reports indicate that due to some off-setting factors, the actual source terms between MOX and LEU are not significantly different despite the inventory differences. However, those source terms were not used to perform an explicit consequence evaluation to draw a conclusion on the overall integrated risk. Even though there are inventory differences and there is the potential for differences in the source term for MOX fuel, the overall uncertainties in the accident progression, fission product release/retention, source term and risk analyses would indicate that there is no significant difference between MOX and LEU fuel. In addition, recent research shows that current guidelines for fission product release (NUREG-1465) are significantly conservative (by a factor of 2). The National Academy of Sciences has stated: “We believe, further, that under these circumstances no important overall adverse impact of MOX use on the accident probabilities of the LWRs [light water reactors] involved will occur, if there are adequate reactivity and thermal margins in the fuel, as licensing review should ensure, the main remaining determinants of accident probabilities will involve facts not related to fuel composition and hence unaffected by the use of MOX rather than LEU Fuel (NAS, 1995).”