ASN Report 2018

With regard to EDF’s nuclear reactors, this review confirmed that the ageing control approach, accompanied by an extensive R&D programme, is appropriate, more particularly given the requirements of the international standards. A national action plan will be drafted in response to the conclusions of this review, notably with regard to the inspections of buried piping and the need for an ageing control programme during the lengthy construction phases of new facilities and prolonged reactor outage periods. 2.11  ̶  Flamanville EPR The EPR is a pressurised water reactor based on a design which is an evolution of the design of the reactors currently in service in France, enabling it to comply with the following reinforced safety objectives: reduction in the number of significant events, mitigation of discharges, reduced volume and activity of waste, reduced individual and collective doses received by the workers (in normal operation and incident situations), reduced overall frequency of core melt, taking account of all types of failures and hazards and reduced radiological consequences of any accidents. After a period of about ten years during which no nuclear reactors were built in France, EDF submitted an application in May 2006 to the Ministers responsible for Nuclear Safety and Radiation Protection for the creation of a 1,650 MWe EPR type reactor on the Flamanville site, already equipped with two 1,300 MWe reactors. The Government authorised its creation by Decree 2007-534 of 10 April 2007, following ASN’s favourable opinion, subsequent to its examination of the application. This Decree was modified in 2017 to extend the time allowed for commissioning of the reactor. After issue of this Creation Authorisation Decree and the building permit, construction of the Flamanville EPR reactor began in September 2007. The first pouring of concrete for the buildings in the nuclear island began in December 2007. Since then, the civil engineering (structural) work has continued and is now almost completed. EDF plans to load fuel and start-up the reactor at the end of 2019. ASN however observes that some welds on the main secondary systems need to be repaired (see p. 15) and that a significant percentage of the start-up tests are still to be carried out. 2.11.1  –  Examination of authorisation applications • The partial commissioning authorisation for the Flamanville EPR reactor for the introduction of steam containing tritium On 26 July 2018, ASN authorised EDF to use steam containing tritium from Flamanville NPP reactors 1 and 2, in addition to or in place of other sources of steam production present on the site (auxiliary and temporary boilers), for preparation for and performance of the hot tests. The introduction of tritium into the facility requires an authorisation referred to as the “partial commissioning authorisation” pursuant to Article 20 of the Decree of 2 November 2007 concerning BNIs and the regulation and oversight of the nuclear safety of the transport of radioactive substances. This authorisation is limited to the period corresponding to the time needed to perform these tests. It states that ASN consent is required prior to initial pressurisation of the main secondary systems, on which certain welds contain flaws. • Examination of the commissioning authorisation application and the partial commissioning authorisation application for the Flamanville 3 reactor to allow arrival of fuel In March 2015, EDF sent ASN its commissioning authorisation application, including the safety analysis report, the general operating rules, a study of waste management in the facility, the on-site emergency plan, the decommissioning plan and an update of the facility’s impact assessment. Following a preliminary examination, ASN considered that all the documents required by the regulations were indeed present, but it considered that additional demonstrations were needed to enable ASN to rule on a possible commissioning authorisation. ASN however initiated technical examination of the subjects for which most of the information was available, although it did submit some requests on certain points. At the same time, EDF sent a partial commissioning application for the facility, to allow the arrival of fuel on the site. In June 2017, ASN received updated versions of the commissioning and partial commissioning authorisation application files. Some elements still need to be provided before ASN is able to issue a position statement on the commissioning authorisation application files. In 2018, ASN notably issued requests for additional data regarding the general operating rules. ASN also obtained the opinion of the Advisory Committee for Reactors (GPR) on 4 and 5 July 2018 concerning the safety analysis report for the Flamanville EPR. This meeting was more particularly devoted to the action taken following the previous GPR sessions devoted to this reactor since 2015. The  Advisory Committee considers that the reactor’s safety case is on the whole satisfactory and points out that some additional information is still required concerning how the fire risk is addressed and the behaviour of the fuel rods which have experienced a boiling crisis. The GPR also considers that the design and dimensioning of the back-up systems and auxiliary safety systems are on the whole satisfactory and observes that additional information is still required concerning the breaks liable to affect the fuel storage pool cooling system. In parallel with its examination of the partial commissioning authorisation application file relating to the use of steam containing tritium, ASN on 28 September 2018 updated its 2010 resolutions defining the limits and procedures for environmental discharge of liquid and gaseous effluents for the nuclear power reactors on the Flamanville site. 2.11.2  –  Monitoring of construction, start-up tests and preparation for operation ASN is faced by numerous challenges when checking construction, start-up tests and preparation for the operation of the Flamanville EPR. They concern: ∙ ∙ checking the quality of equipment manufacturing and installation construction in a manner commensurate with the safety, radiation protection and environmental protection issues, in order to be able to rule on the ability of the installation to meet the defined requirements; ∙ ∙ ensuring that the various stakeholders learn the lessons from the construction and start-up testing phase, including the upstream phases (selection and monitoring of contractors, construction, procurement, etc.) which will enable the as-built installation to comply with the safety case for the duration of the project; 310  ASN report on the state of nuclear safety and radiation protection in France in 2018 10 – EDF NUCLEAR POWER PLANTS