Abstracts ASN Report 2021

SITES UNDERGOING DECOMMISSIONING Superphénix reactor and fuel storage facility The Superphénix fast neutron reactor (BNI 91), a 1,200 MWe sodium-cooled industrial prototype is situated at CreysMalville in the Isère département. It was def initively shut down in 1997. The reactor has been unloaded and the majority of the sodium has been neutralised in concrete. Superphénix is associated with another BNI, the APEC fuel storage facility (BNI 141). The APEC essentially comprises a pool containing the fuel unloaded from the reactor pressure vessel and the area for storing the soda concrete packages resulting from neutralisation of the sodium from Superphénix. EDF has submitted the periodic safety review concluding reports for BNI 141 and BNI 91. ASN made public its conclusions concerning the Superphénix periodic safety review on 28 July 2021 and has approved continuation of the decommissioning operations. It made a draft resolution governing continued operation of APEC available for public consultation from 23 September to 8 October 2021. ASN considers that the safety of Superphénix decommissioning operations and of APEC operation is on the whole satisfactory. In 2018, ASN authorised commencement of the second Superphénix decommissioning phase, which consists in opening the reactor pressure vessel to dismantle its internal components, in dedicated facilities constructed in the reactor building, by direct or remote manipulation. The site has fallen behind schedule with the “core cover plug” cutting operations, due to technical difficulties with the cutting robot. The safety and radiation protection measures implemented by EDF for these operations are on the whole satisfactory. In 2020, ASN carried out a reactive inspection further to a f ire outbreak that led EDF to activate its PUI. Shortcomings had been discovered at various levels in the course of the procedures. An unannounced night-time fire exercise carried out by ASN in September 2021 revealed the persistence of certain malfunctions in the licensee’s organisation. Concerning the management of facility obsolescence, EDF reported difficulties in procuring certain items of equipment and significant delays in the replacement and repair of parts. ASN has asked the licensee to carry out a site-level diagnosis and to draw up an action plan on this subject. An inspection carried out in the first quarter of 2021 revealed that the plan had effectively been initiated but there were delays in its application. ASN will be particularly attentive in 2022 to the improvement of the site’s emergency organisation and to the management of deviations, judged unsatisfactory in the course of several inspections. Siloette, Siloé, LAMA reactors and effluents and solid waste treatment station – CEA Centre The CEA Grenoble centre (Isère département) was inaugurated in January 1959. Activities associated with the development of nuclear reactors were carried out there before being gradually transferred to other CEA centres in the 1980’s. The Grenoble centre now carries out research and development in the areas of renewable energies, health and microtechnology. In 2002, the CEA Grenoble centre began a site delicensing process. The site accommodated six nuclear installations which have gradually stopped their activities and are now in the decommissioning phase with a view to delicensing. Delicensing of the Siloette reactor was declared in 2007, that of the Mélusine reactor in 2011, of the Siloé reactor in January 2015 and of the LAMA reactor in August 2017. The last BNIs on the site (BNI 36 and 79) are the Effluents and Solid Waste Treatment Station and the decay storage facility (STED). All the buildings have been dismantled, in accordance with their decommissioning decree. With regard to radiological and chemical remediation of the STED soils, all the operations technically achievable at a reasonably acceptable cost have been carried out. In view of the presence of residual chemical and radiological contamination, the licensee submitted a new delicensing file in June 2021 which is currently being examined by ASN, which refused its first file in 2019. This delicensing will be subject to the implementation of active institutional controls. ABSTRACTS – ASN Report on the state of nuclear safety and radiation protection in France in 2021 49 REGIONAL OVERVIEW OF NUCLEAR SAFETY AND RADIATION PROTECTION AUVERGNE-RHÔNE-ALPES