Experience of safeguards implementation at Rokkasho Enrichment Plant (REP) and an innovative safeguards approach for new plant

Rokkasho Enrichment Plant (REP) has been operating since 1992 with safeguards implemented on the basis of the Hexapartite Safeguards Project (HSP) concept. Achievement of safeguards defined by HSP entails a set of safeguards measures whose application by the inspectorate permits the detection in a timely manner and with high confidence of the diversion of a significant quantity of uranium, including the production of a significant quantity of uranium at an enrichment level higher than declared. Limited frequency unannounced access (LFUA) to cascade areas has been implemented. However, further improvement of the safeguards approach is needed, especially continuity of knowledge on Physical Inventory Verification (PIV) under the condition of in-operation PIT, and effective flow verification for UF6 cylinder movements. Therefore Japan Nuclear Fuel Limited (JNFL) has studied a new safeguards approach which would provide effective and efficient safeguards from the following viewpoints: - securing of safety for the facility operation, - achievement of the international safeguards requirements, - securing of economy for production, and - use of operator's equipment with authentication for the inspections. A plan for a new safeguards approach has been established based on a non-destructive assay (NDA) system with remote monitoring capability to verify the nuclear material flow in the process and LEU production (uranium quantity and enrichment) remotely. The remote monitoring will provide optimization of the Agency resources for both inspection activities on declared enrichment operations and detection of undeclared activities. This paper presents experience on the safeguards implementation at REP, current improvement for UF6 cylinder movement verification by surveillance cameras, group seal approach at the UF6 storage and an innovative safeguards approach based on NDA system with remote monitoring for declared facilities