Abstracts ASN Report 2021

“ The generic phase of the periodic safety review concerns the 900 MWe reactors, the oldest reactors in operation in France.” The generic review phase, common to the 32 reactors of 900 MWe, enabled the safety improvements to be deployed on all the reactors to be determined ASN considers that these safety improvements will make it possible to bring the level of safety of the 900 MWe reactors close to that of the most recent reactors (third generation), in particular: • by improving the way potential hazards (earthquake, flooding, explosion, fire, etc.) are taken into account. The reactors will also be able to cope with more severe hazards than those hitherto considered; • by reducing the risk of accident with core melt and mitigating any consequences of this type of accident. These provisions will thus lead to a significant reduction in environmental releases during this type of accident; • by mitigating the radiological consequences of the accidents studied in the safety report. This will significantly reduce the occurrence of situations that involve implementing population protection measures (sheltering, evacuation, taking iodine tablets); • by improving the provisions for managing accident situations affecting spent fuel pools. In its resolution 2021-DC-0706 of 23 February 2021, ASN prescribed the implementation of the major safety improvements planned by EDF, along with additional measures it considers necessary to achieve the objectives of the safety review. ASN underlines the ambitious objectives of the fourth periodic safety review of the 900MWe reactors and the substantial work carried out by EDF in the generic phase. It also underlines the scale of the modifications planned by EDF, the implementation of which will bring about significant safety improvements. In 2019, EDF began to deploy these improvements during the fourth ten-yearly outages The provisions determined during the generic stage of the safety review and those that will be defined in the studies specific to each site, will have to be applied on each reactor with a view to its continued operation. ASN asked EDF to carry out the majority of the safety improvements before submitting the safety review concluding report, and in practice during the ten-yearly outage of each reactor. At the end of 2021, EDF had carried out or initiated seven of these ten-yearly outages. ASN is conducting reinforced oversight of these ten-yearly outages, with regard to both EDF’s verification of the conformity of the installations with the safety rules, and deployment of the safety improvements. ASN considers that these ten-yearly outages are being conducted relatively satisfactorily. EDF is devoting considerable human resources to preparing and conducting them. Considerable industrial capacity to be mobilised Every year, EDF has to carry out the fourth ten-yearly outages for four to five 900 MWe reactors. This work entails a significant increase in the industrial workload in the sector. ASN asked EDF to report annually on the industrial capacity of both itself and its suppliers to complete the modifications to the facilities on schedule. The public is involved throughout the review process The measures set out by EDF during the generic phase of the review underwent public participation from September 2018 to March 2019, under the aegis of the High Committee for Transparency and Information on Nuclear Safety. ASN also consulted the public regarding the objectives of the review in 2016 and the conclusion of the generic phase at the end of 2020. Finally, the measures set out by EDF in the periodic safety review concluding report for each reactor shall be subject to a public inquiry. That of Tricastin Nuclear Power Plant reactor 1 took place in early 2022. 4th periodic safety review process ASN resolution and requirements AUTORITÉ DE SÛRETÉ NUCLÉAIRE #02 • FEBRUARY 2021 NUCLEAR POWER PLANTS GOING BEYOND 40 YEARS What are the conditions for the continued operation of EDF’s 900MWe reactors? Involvement of the various audiences in the resolution LES CAHIERS DE L’ASN #02 Read online Le Cahier de l’ASN #02 on french-nuclear-safety.fr ABSTRACTS – ASN Report on the state of nuclear safety and radiation protection in France in 2021 27 NOTABLE EVENTS 2021