supplemented further to the request from ASN. On completion of its analysis, ASN indicated in December 2021 that it has no objection to the continued operation of BNIs 133 (Chinon A1 reactor), 153 (Chinon A2 reactor) and 161 (Chinon A3 reactor). It will verify during the examination of the decommissioning files for these reactors, submitted by EDF at the end of 2022 and still being examined, that the decommissioning operations will be carried out under suitable conditions of safety and radiation protection, within controlled time frames. For the Chinon A2 reactor, EDF has continued the decommissioning preparation operations situated outside the reactor pressure vessel, particularly as concerns removal of the shells from the heat exchanger premises, and continued the investigations inside the pressure vessel. The shells of two of the four heat exchanger premises have been removed. EDF also continued the decommissioning of the Chinon A3 heat exchangers. After completing the decommissioning work in the South heat exchangers room in 2022, the decommissioning work in the North heat exchangers room, which started in June 2022, was completed in 2023. All the cylinders have been transferred to the Cires facility (Industrial centre for collection, storage and disposal). The storms of June and September 2023 led to the infiltration of several hundred cubic metres of water into the premises adjacent to the Chinon A1 turbine building and into various premises of Chinon A3. ASN conducted an inspection on this subject, which concluded on the importance of implementing preventive and corrective actions to remedy this situation (pumping the water, conducting surveillance rounds after storms, waterproofing work on walls and slabs, repair and/or tilting of the storm water downpipes). ASN considers that the level of safety of the Chinon nuclear installations undergoing decommissioning (Chinon A1, A2 and A3) is satisfactory. The inspections carried out in 2023 highlighted in particular the quality of the inventory of waste with no disposal route which is currently being drawn up, the good preparation of the various decommissioning work sites and the work carried out on the identification of the causes and the immediate corrective measures further to the water infiltrations. However, the notification of four significant events relating to radiation protection must be noted, particularly concerning entries into controlled areas without wearing an active dosimeter. The actions implemented and checked during inspections are expected to limit the recurrence of such deviations. Improvements are expected in subcontractor tracking and monitoring, whether in radiation protection or the monitoring of work sites or in the depth of the analyses of important radiation protection events. 2. Inerting in this instance is a process enabling the radiological activity of the magnesian waste to be contained in an enclosure of specific materials to allow risk-free transportation and storage. “NUCLEAR FUEL CYCLE” FACILITIES Inter-regional fresh fuel warehouse Commissioned in 1978, the Chinon Inter-Regional Fresh Fuel Warehouse (MIR) is a facility for storing fresh fuel assemblies pending their utilisation in various EDF reactors. It constitutes BNI 99. Along with the Bugey MIR, it contributes to the management of flows of fuel assembly supplies for the reactors. The facility has been operating nominally since the reception and storage of fresh fuel assemblies resumed in 2020, in a configuration in which the facility was equipped with a new handling crane in 2019 and under an updated baseline authorised by ASN. During its inspection in 2023, ASN found that the level of safety could be improved, despite the good upkeep of the premises. Indeed, ASN considers that the MIR management teams need to improve the assimilation of the documentation system and associated baseline requirements. RESEARCH FACILITIES UNDERGOING DECOMMISSIONING Irradiated materials facility The Irradiated Material Facility (AMI), which was declared and commissioned in 1964, is situated on the Chinon nuclear site and operated by EDF. This facility (BNI 94) has stopped operating and is being decommissioned. It was intended essentially for performing examinations and expert assessments on activated or contaminated materials from pressurised water reactors. The expert assessment activities were completely transferred in 2015 to a new facility on the site, the Integrated Laboratory (Lidec) of the Construction and Operation Expert Appraisal and Inspection Centre (Ceidre). Decree 2020-499 for AMI decommissioning was published on 30 April 2020 and the new RGEs were approved by ASN in April 2021, thereby enabling the Decree to enter into application. ASN also subjected the starting of several future decommissioning operations to its approval. Further to the updating of the resolution regulating the installation’s discharge limits in July 2022, a new discharge monitoring system has been put into service and decommissioning operations have started that include equipment cutting-up and interventions in several facilities. The legacy magnesian waste from the expert assessments of certain parts requires inerting operations(2) in order to meet the disposal criteria of the French Radioactive Waste Management Agency (Andra). As the characterisation results differed from what was expected, the necessary waiver was obtained from Andra in late 2022, thereby allowing the waste to be accepted. A work school was set up in early 2023. ABSTRACTS – ASN Report on the state of nuclear safety and radiation protection in France in 2023 51 Regional overview of nuclear safety and radiation protection • CENTRE-VAL DE LOIRE •
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