ASN Report 2022

Cruas-Meysse nuclear power plant Commissioned between 1984 and 1985 and operated by EDF, the Cruas-Meysse NPP is situated in the Ardèche département on the municipalities of Cruas and Meysse and comprises four PWRs of 900MWe each. Reactors 1 and 2 constitute BNI 111 and reactors 3 and 4 constitute BNI 112. ASN considers that the overall performance of the CruasMeysse NPP with regard to nuclear safety is below ASN’s general assessment of EDF plant performance. However, it considers that the overall performance of the Cruas‑Meysse NPP with regard to radiation protection and environmental protection is in line with ASN’s general assessment of EDF plant performance. With regard to nuclear safety, in 2022 ASN observed an increase in deviations and non-qualities in the maintenance activities during the four reactor outages carried out in 2022 and considers that the quality of the maintenance activities does not meet expectations. Only the reactor 1 outage went satisfactorily on the whole. Furthermore, the occurrence of several significant events concerning situations of noncompliance with the General Operating Rules (RGEs) shows that the operating rigour must also be improved. In addition, ASN’s inspection campaign on the theme of the operating team’s skills management revealed shortcomings leading ASN to ask EDF to implement corrective actions. ASN therefore expects the site to increase rigour in its operation and maintenance activities before the first of the site’s fourth ten‑yearly outages, which concerns reactor 3 and will start in 2024. As far as radiation protection is concerned, 2022 is in line with the preceding years, with controlled collective exposure of workers but difficulties in obtaining satisfactory levels of radiological cleanliness during the reactor outages and maintaining the containment air locks of the worksite areas in good condition. These situations still lead to worker contamination events – without exceeding the authorised doses, and to contaminations of the roadways. With regard to environmental protection, ASN notes that the management of waste and the storage areas is now satisfactory. Progress is nevertheless required in the containment of effluents. As in 2021, ASN notes shortcomings in the control of the risk of dispersion and proliferation of legionella in the tertiary circuit where progress must be made. The site’s results in occupational health and safety are satisfactory. The accident rate remains under control, although efforts must nevertheless be made in controlling the risk of falling from height and when using construction machinery and lifting equipment. A serious accident occurred during the use of an aerial work platform. TRICASTIN SITE The Tricastin nuclear site, situated in the Drôme and Vaucluse départements, constitutes a vast industrial site accommodating the largest concentration of nuclear and chemical facilities in France. It is situated on the right bank of the Donzère‑Mondragon Canal (a diversion channel of the river Rhône) between Valence and Avignon. It occupies a surface area of 800 hectares covering three municipalities, namely Saint‑Paul‑Trois‑Châteaux and Pierrelatte in the Drôme département, and Bollène in the Vaucluse département. The site harbours a large number of installations, with a NPP comprising four 900 MWe reactors, “nuclear fuel cycle” facilities, and lastly the Operational Hot Unit (BCOT) which fulfilled maintenance and storage functions. Tricastin nuclear power plant The Tricastin NPP comprises four 900 MWe PWRs: reactors 1 and 2 were commissioned in 1980 and constitute BNI 87, while reactors 3 and 4, commissioned in 1981, constitute BNI 88. ASN considers that the nuclear safety performance of the Tricastin NPP stands out positively with respect to its general assessment of the EDF plants, and that its radiation protection and environmental protection performance is in line with the ASN’s general assessment of the EDF nuclear fleet. With regard to nuclear safety, ASN considers that the performance of the NPP has improved. The site has made progress in equipment maintenance and operation of the facilities. In 2022, the four reactors of the Tricastin NPP were shut down for scheduled maintenance and partial refuelling. Reactor 3 underwent its fourth ten‑yearly outage and the modifications planned to enhance safety were integrated satisfactorily. ASN considers that EDF satisfactorily carried out the planned activities for the four reactor outages and complied with the corresponding safety requirements. Vulnerabilities were nevertheless observed in the control of the fire risk associated in particular with the maintenance of fire-fighting means and two reported significant events are related to this risk. ASN nevertheless noted the occurrence of several significant events during the last quarter of 2022 linked to the planning and preparation of the maintenance activities, and will remain attentive to this in 2023. ASN considers that the radiation protection performance of the NPP is slightly down compared with 2021. Several significant events were effectively reported and deficiencies in the control of radiological cleanliness were noted. Likewise, several cases of worker contamination detection at the site exit were reported in 2022. ASN nevertheless noted improvements in worker dosimetry during the reactor 1 outage at the end of 2022. ABSTRACTS – ASN Report on the state of nuclear safety and radiation protection in France in 2022 41 Regional overview of nuclear safety and radiation protection • AUVERGNE‑RHÔNE‑ALPES •