CONSIDERATIONS ON THE RE-VERIFICATION OF NUCLEAR MATERIAL UNDER C/S IN THE FRAMEWORK OF INTEGRATED SAFEGUARDS

The requirements for re-verification of nuclear material under containment and surveillance in the framework of integrated safeguards are analyzed. Considering the definition of single and dual C/S systems, the impact of the implementation of integrated safeguards approach for specific facility types on the integrated safeguards criteria is assessed. For a single C/S system, traditional criteria require that the system be verified during any interim inspection. In addition, during the Physical Inventory Verification (in most cases once a year) and even after an C/S evaluation with positive conclusive results, it is required to re-verify the inventory of nuclear material. Such re-verification is carried out with a probability lower than the one applicable in case of no existence of the single system. Under integrated safeguards, considering the specific facility safeguards approaches and the implementation of randomized inspections in time and space, new requirements for re-verification are proposed.