SAFEGUARDS FOR MOX FUEL ASSEMBLIES IN LIGHT-WATER REACTORS

In the Federal Republic of Germany thermal recycling programmes have been implemented for the utilization of plutonium arising from reprocessing. The plutonium is consumed in mixed oxide fuel assemblies at LWR power plants. The compilation of a safeguards concept for fresh MOX fuel, practicable both for the safeguards inspectorates and reactor operators should be based on existing safeguards measures. These have to be supplemented, however, because the high strategic value of fresh MOX fuel as compared to uranium assemblies implies a detection period of four weeks. In addition, plutonium in fresh MOX fuel is more easily accessible than plutonium in spent fuel. A safeguards concept for fresh MOX requires increased inspector presence and implementation of adequate containment and surveillance measures to ensure verfication of identity and integrity of the assemblies in the various locations of the reactor. Novel C & S systems are entering into the implementation phase and could be adequate. The paper discusses the problem and possible safeguards solutions.