2.9.2 The periodic safety review The principle of the periodic safety review Every ten years, EDF must carry out a periodic safety review of its installations. The periodic safety reviews of nuclear power reactors comprise the following two steps: ∙ A check on the condition and conformity of the facility: this first step aims to assess the situation of the installation with respect to the rules applicable to it. It is based on a range of inspections and tests in addition to those performed in realtime. These verifications may comprise design reviews, as well as field inspections of the equipment, or even ten-yearly tests such as the containment pressure tests. Any deviations detected during these investigations are then restored to conformity within a time-frame commensurate with their potential consequences. Ageing management is also incorporated into this part of the review. ∙ The safety reassessment: this second step aims to improve the level of safety, notably taking account of the experience acquired during operation, changing knowledge, the requirements applicable to the more recent installations and international best practices. Following these reassessment studies, EDF identifies the changes it intends to make to its facilities in order to enhance safety. The review process for the EDF nuclear power reactors In order to benefit from the standardisation of its nuclear power reactors, EDF first of all implements a generic studies programme for a given type of reactor (900MWe, 1,300MWe or 1,450MWe reactors). The results of this programme are then applied to each nuclear power reactor on the occasion of its periodic safety review. EDF more particularly carries out a large part of the checks and modifications related to the periodic safety reviews during the ten-yearly inspections of its reactors. In accordance with the provisions of Article L. 593-19 of the Environment Code, following this periodic safety review, the licensee sends ASN a periodic safety review concluding report. In this report, the licensee states its position on the conformity of its facility and details the modifications made to remedy deviations observed or to improve the safety of the facility and, as necessary, specifies the additional improvements that it will be making. ASN analysis ASN examines the periodic safety reviews in several stages. It first of all issues a position statement on the objectives of the review and the guidelines of the generic programmes to verify the state of the installation and the safety reassessment proposed by EDF, after obtaining the opinion of the Advisory Committees of Experts (GPEs). On this basis, EDF carries out safety reassessment studies and defines the modifications to be made. ASN then issues a position statement on the results of these studies and on these modifications, after again consulting the GPEs. This position statement closes the generic phase of the periodic safety review, common to all the reactors. This generic assessment does not take account of any specific individual aspects and ASN gives a ruling on the suitability of each nuclear power reactor for continued operation, notably on the basis of the results of the conformity checks and the assessment made in the periodic safety review concluding report for the reactor submitted by EDF. Following examination of the periodic safety review concluding report for each reactor, ASN communicates its analysis to the Ministry responsible for nuclear safety. It can issue new requirements governing its continued operation. The Energy Transition for Green Growth Act 2015-992 of 17 August 2015 supplemented the framework applicable to the periodic safety reviews on nuclear power reactors. It more specifically requires ASN authorisation, following a public inquiry, of the provisions proposed by the licensee during the periodic safety reviews beyond the 35th year of operation of a nuclear power reactor. Five years after submitting the periodic safety review report, the licensee also submits an interim report on the condition of these equipment items, in the light of which ASN may supplement its prescriptions. 2.9.3 Ongoing periodic safety reviews in the Nuclear Power Plants The fourth periodic safety review A high-stakes review EDF’s 32 reactors of 900 MWe in operation were commissioned between 1978 and 1987. The first ones have reached the milestone of their fourth periodic safety review. This fourth periodic safety review comprises particular challenges: ∙ Some items of equipment are reaching their design-basis lifetime. The studies concerning the conformity of the installations and the management of equipment ageing therefore need to be reviewed to take account of the degradation mechanisms actually observed and the maintenance and replacement strategies implemented by EDF. CAMPAIGN OF IN-DEPTH RADIATION PROTECTION INSPECTIONS Every year, ASN runs a campaign of in-depth inspections on the topic of radiation protection in several EDF NPPs. These campaigns are a means of identifying good practices and points needing improvement that could potentially be transposed to all the NPPs. The 2022 campaign was held in the Gravelines, Flamanville and Paluel NPPs and concerned the organisation and management of radiation protection, control of worksites in controlled areas, notably during radiography work, application of the Optimisation Principle, control of the risk of the dissemination of contamination within installations and management of radioactive sources. The inspections focused primarily on field checks and measurements. The inspectors also carried out situational exercises for treating contaminated persons. The inspectors found a good general organisation, but also observed the unsatisfactory state of a number of premises (site laundries, zones used to extract contaminated equipment, etc.) in terms of control of worker radiation protection and radiological cleanness. They also noted that not all the sites inspected showed the required level regarding the applicable requirements in terms of marking out and signage of radiographic inspection worksites. After each of these inspections ASN sent improvement requests to EDF. 310 ASN Report on the state of nuclear safety and radiation protection in France in 2022 • 10 • The EDF Nuclear Power Plants 10
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