ASN Report 2017

373 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 12  - EDF Nuclear Power Plants Bilateral relations ASN enjoys close relations with foreign nuclear regulators in order to share previous and current experience of authorisation procedures and regulation of the construction of new reactors. Since 2004, reinforced cooperation has existed with the Finnish nuclear safety regulator (STUK, Säteilyturvakeskus ) around the construction of the Olkiluoto (Finland) and Flamanville (France) reactors. In 2017, a technical progress meeting concerning the two projects was held in France and a visit to the Flamanville reactor 3 construction site was organised. The discussions more specifically concerned the start-up tests for these reactors. Multinational cooperation Some international structures such as the Nuclear Energy Agency (NEA) and the Western European Nuclear Regulators Association (WENRA) also provide opportunities for exchanges on practices and lessons learned from overseeing reactor construction. ASN is a member of the Multinational Design Evaluation Programme (MDEP) which evaluates the design of new reactors (see point 3.3 of chapter 7). The plenary group devoted to EPR type reactors met twice in 2017. With the support of IRSN, ASN took part in the work concerning severe accidents, I&C, probabilistic safety assessments and the modelling of accidents and transients and the inspection of suppliers and in the work by the new technical group, set up in 2016 to deal with preparations for the commissioning of new reactors. ASN thus took part in a visit to Taishan reactor 1 to attend certain start-up tests on this reactor, as well as a visit to Olkiluoto reactor 3. For ASN, these international exchanges are one of the driving forces behind the harmonisation of safety requirements and inspection practices. 2.12 Studies on reactors of the future EPR new model In April  2016, EDF asked ASN for its opinion on the safety options for a new reactor called the EPR new model (EPR NM). This PWR project currently being developed by a team combining EDF and Areva NP, aims to address the general safety objectives of the third generation of reactors. With this reactor, the EPR NM project aims to integrate the lessons learned from the design, construction and commissioning of the EPR reactors at Flamanville 3, Olkiluoto 3, Taishan 1 and 2 and Hinkley-Point C, along with operating experience feedback from existing reactors. Moreover, the design of this reactor aims to incorporate all the lessons learned from the Fukushima Daiichi accident. This more specifically entails reinforcing the design against natural hazards and consolidating the independence of the installation and the site in an accident situation (with or without core melt) until such time as the off-site emergency services can intervene. The technical examination of the Safety Options File (DOS) by ASN with the support of IRSN, took place during 2017 and takes account of the recommendations of ASN Guide No. 22 concerning PWR design. ASN will issue a position statement on the safety options for the EPR NM project in 2018. FOCUS ASN Guide No. 22 on the design of pressurised water reactors Produced jointly with IRSN, ASN Guide No. 22 contains nuclear safety recommendations for the design of pressurised water reactors. This guide takes into consideration: ཛྷ ཛྷ experience feedback from the technical examinations already conducted on new reactor projects; ཛྷ ཛྷ lessons learned from the Fukushima Daiichi accident and the subsequent stress tests; ཛྷ ཛྷ international publications, particularly those produced by the Western European Nuclear Regulators’ Association (WENRA) and the International Atomic Energy Agency (IAEA). The common technical positions set out in this guide are the culmination of several years of work by ASN and IRSN during which technical discussions were held with the industry players. The guide was examined by the GPR, in conjunction with members of the GPESPN. It also took into consideration the comments stemming from the public consultation conducted via the ASN website in September 2016. The guide focuses essentially on the prevention of radiological incidents and accidents and the mitigation of their consequences. It details the general design objectives and principles and makes recommendations to help meet regulatory requirements. After giving recommendations of a general nature primarily concerning defence in depth or the nuclear safety case, the guide focuses on the barriers that must be placed between radioactive substances and people and the environment, and on the safety functions. Lastly, it provides recommendations concerning specific subjects such as the storage of fuel assemblies. ASN Guide No. 22 thus constitutes a reference in France for the design of new reactors and a tool for presenting French nuclear safety practices on the international stage. The recommendations provided in this guide can also be used when seeking to make improvements to the reactors currently in service, particularly during their periodic safety reviews.