ASN Report 2017

370 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 12  - EDF Nuclear Power Plants EDF plans to load fuel and start-up the reactor at the end of 2018. ASN however observes delays in the transmission of certain documents for the ongoing investigations, notably with regard to the NPE. 2.11.1 The steps up to commissioning of the Flamanville EPR Pursuant to the Decree of 2nd November 2007 as amended (see chapter 3, point 3.1.3), the introduction of nuclear fuel within the perimeter of the installation and the performance of particular operating tests on the installation involving the introduction of radioactive substances into it, require partial commissioning authorisation by ASN. The introduction of nuclear fuel into the reactor vessel requires a commissioning authorisation fromASN. In addition, prior to commissioning, all the NPE shall have obtained an individual certificate of compliance and EDF shall have completed the Pre-service Inspection (VCI) on the main primary and secondary systems in order more particularly to ensure the feasibility of the planned in-service maintenance, before fuel is loaded. 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: ཛྷ ཛྷ checking the quality of equipment manufacturing and installation construction and testing 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; ཛྷ ཛྷ ensuring that the various stakeholders learn the lessons from the construction 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; ཛྷ ཛྷ ensuring that the start-up tests programme is satisfactory, correctly performed and that the expected results are obtained; ཛྷ ཛྷ ensuring that the licensee take the necessary steps so that the teams in charge of operating the installation after commissioning are well-prepared. To do this, ASN has set binding requirements regarding the design, construction and start-up tests for the Flamanville 3 reactor and for operation of the two Flamanville 1 and 2 reactors close to the construction site. As this is a nuclear power reactor, ASN is also responsible for labour inspectorate duties on the construction site. Finally, ASN oversees the manufacture of the NPE that will form part of the primary and secondary systems of the nuclear steam supply system. The main steps taken by ASN in 2017 are described below. Examination of the commissioning authorisation application and the partial commissioning authorisation application for the Flamanville 3 reactor In March 2015, EDF sent ASN its commissioning authorisation application and its partial commissioning application, including the safety analysis report, the general operating FOCUS Anomaly in the composition of the steel for the Flamanville EPR reactor pressure vessel closure head and bottom head In 2014, measurements taken by Areva NP showed the presence of a significant carbon concentration in the steel at the centre of the Flamanville EPR reactor pressure vessel closure head and bottom head. At the end of 2015, the approach proposed by Areva NP to demonstrate the sufficiency of the mechanical properties of the material used in the manufacture of the Flamanville EPR reactor pressure vessel closure head and bottom head was presented to the GPESPN. Subject to its observations and demands being taken into account, ASN considered that the approach proposed by Areva NP is acceptable in principle as it is based on a vast programme of mechanical and chemical tests. The test programme was run during the course of 2016. Areva NP transmitted a technical file more particularly presenting the results of the test programme in December  2016 and the demonstration of the serviceability of the reactor pressure vessel. ASN and its technical support organisation, IRSN, analysed this file and obtained the opinion of the GPESPN, which met on 26th and 27th June 2017. ASN was thus able to present its draft opinion on the Flamanville EPR reactor pressure vessel anomaly on 28th June 2017. After consulting the public and the High Council for the prevention of technological risks, ASN submitted its opinion on the anomaly in the steel used in the Flamanville EPR reactor pressure vessel bottom head and closure head on 10th October 2017. The results of the test programme show that the mechanical properties of the material are sufficient to prevent the risk of fast fracture, given the loads applied and taking account of the most unfavourable flaw. ASN thus considers that this anomaly is not such as to compromise the commissioning of the reactor pressure vessel, provided that specific checks are carried out during operation of the installation, to ensure that no flaws appear. As the feasibility of these checks cannot at present be confirmed for the closure head, ASN considers that the current closure head cannot be used beyond 2024. The commissioning of the Flamanville EPR reactor pressure vessel also remains dependent on an authorisation issued on the basis of demonstration of the serviceability of all its components. Hydrotesting of the entire main primary system, of which the reactor pressure vessel is a part, took place on 5th January 2018. Framatome (ex-Areva NP) intends to send ASN a file substantiating the reactor pressure vessel commissioning authorisation application during the second quarter of 2018. The examination of this file could lead to ASN issuing a position statement on the commissioning of the vessel before the third quarter of 2018.