ASN Report 2022

CERN accelerators and research centre Following the signing of an international agreement between France, Switzerland and the European Organisation for Nuclear Research (CERN) on 15 November 2010, ASN and the Swiss Federal Office of Public Health (OFSP) – the Swiss radiation protection oversight body – are contributing to the verification of the safety and radiation protection 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 definitively 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. In the light of the APEC periodic safety review conclusions, ASN has regulated its continued operation through a resolution of 17 March 2022 setting requirements concerning the control of the seismic-related risks, beyond design-basis accident situations, removal of the fuel and waste stored in the pool, the handling operations and the management of soda blocks. 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. In 2022, the large rotating plug was cut into three pieces placed on specific accommodation platforms located on the slab and the vessel was covered by a containment structure to keep it sealed pending its decommissioning. In 2019, EDF discovered legacy hydrocarbon pollution of the soils in a perimeter near a former buffer pond. ASN is currently examining a soil management plan. ASN considers that the organisation and the measures implemented by the licensee on 2022 ensure good upkeep of the facilities and good tracking of the various commitments made to ASN. requirements applied by CERN. The joint actions concern transport, waste and radiation protection. Two joint visits by the Swiss and French authorities took place in 2022 on the subject of management of the on-site waste processing centre and the monitoring of outsidecontractors. These visits found the practices to be satisfactory. 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 Grenoblecentrebegana site delicensing process. The site accommodated six nuclear installations which have gradually stopped their activities and are now in the decom - missioning 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 Stationand the decay storage facility (STED). All the buildings have been dismantled, in accordance with their decommissioning decree. With regard to radiologicaland chemical remediationof the STED soils, all the operations technically achievable at a rea - sonably 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 is subject to the implemen - tation of active institutionalcontrols. An order instituting the institutional controls was issued by the Prefect of Isère département in December 2022. 46 ABSTRACTS – ASN Report on the state of nuclear safety and radiation protection in France in 2022 Regional overview of nuclear safety and radiation protection • AUVERGNE‑RHÔNE‑ALPES •