Experience of Integrated Safeguards Approach for Large-scale Hot Cell Laboratory

The Japan Atomic Energy Agency (JAEA) has been operating a large-scale hot cell laboratory, the Fuels Monitoring Facility (FMF), located near the experimental fast reactor Joyo at the Oarai Research and Development Center (JNC-2 site). The FMF conducts post irradiation examinations (PIE) of fuel assemblies irradiated in Joyo. The assemblies are disassembled and non-destructive examinations, such as X-ray computed tomography tests, are carried out. Some of the fuel pins are cut into specimens and destructive examinations, such as ceramography and X-ray micro analyses, are performed. Following PIE, the tested material, in the form of a pin or segments, is shipped back to a Joyo spent fuel pond. In some cases, after reassembly of the examined irradiated fuel pins is completed, the fuel assemblies are shipped back to Joyo for further irradiation. For the IAEA to apply the integrated safeguards approach (ISA) to the FMF, a new verification system on material shipping and receiving process between Joyo and the FMF has been established by the IAEA under technical collaboration among the Japan Safeguard Office (JSGO) of MEXT, the Nuclear Material Control Center (NMCC) and the JAEA. The main concept of receipt/shipment verification under the ISA for JNC-2 site is as follows: under the IS, the FMF is treated as a Joyo-associated facility in terms of its safeguards system because it deals with the same spent fuels. Verification of the material shipping and receiving process between Joyo and the FMF can only be applied to the declared transport routes and transport casks. The verification of the nuclear material contained in the cask is performed with the method of gross defect at the time of short notice random interim inspections (RIIs) by measuring the surface neutron dose rate of the cask, filled with water to reduce radiation. The JAEA performed a series of preliminary tests with the IAEA, the JSGO and the NMCC, and confirmed from the standpoint of the operator that this system could be used for verification purposes under the ISA. It is clear that application of the system under the ISA would improve the transparency of the material shipping and receiving process and the system established by the IAEA with the JSGO, the NMCC and the JAEA would successfully contribute to strengthening the effectiveness and efficiency of JNC-2 safeguards. Short notice RII will be also applied to material transfer between the FMF and the prototype fast breeder reactor, Monju. (author)