ASN Report 2017

241 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 08  - Regional overview of nuclear safety and radiation protection NORMANDIE safety. The main primary system of reactor 3 underwent complete requalification. This outage went smoothly. However, a major technical incident affecting one of the reactor coolant pump sets obliged the licensee to unload the reactor core after having reloaded it, in order to carry out the necessary work. With regard to reactor 2, continuation of the 10-yearly outage consisted essentially in restoring the conformity of the equipment damaged by the fall of the steam generator in 2016 and preparing for resumption of the steam generator replacement operations which were started in this reactor in early 2016. ASN considers that performance of these operations was satisfactory on the whole. It notes that removal of the last old steam generator and introduction of the four replacement steam generators at the end of 2017 involved intensive work in both engineering and dealing with problems on the handling line. ASN considers that the refuelling outage of reactor 4 was satisfactory. ASN does however note that EDF must take better account of the seismic interaction risk on the worksites in the reactor building. In the area of radiation protection, ASN notes an improvement compared with 2016. The site’s organisation must however be bolstered, particularly in the preparation of activities involving radiological risks and the monitoring of outside contractors. With regard to environmental protection, the site must reinforce its organisation to guarantee the leak-tightness of the cooling units. In addition, the file submitted by EDF to request modifications to the site’s discharge authorisations was made available for public consultation in 2017 and its examination should be concluded in 2018. Penly nuclear power plant ASN considers that the performance of the Penly NPP with regard to nuclear safety, radiation protection and environmental protection is, on the whole, in line with the general assessment of EDF plant performance. ASN did nevertheless detect several low-level events in 2017, particularly during the inspections, indicating that safety management must be stepped up. Operating experience feedback management and internal checks on the site must be improved. With regard to operation and reactor management, ASN considers that the site’s performance is satisfactory on the whole. However, although operating rigour has improved in certain activities, as is the case for the configuring of systems, it must be further improved for the activities relating to the periodic tests. The site must also be particularly attentive to compliance with instructions and the quality and usability of the operating documents. The maintenance performance of the site remains stable. ASN has nevertheless detected deficiencies in maintenance work preparation and implementation. ASN considers that the site must make further progress in the in-service monitoring of Nuclear Pressure Equipment (NPE). Particular care must be taken to ensure that deviations affecting the installation are characterised and corrected within appropriate time frames. The maintenance operations carried out during the reactor 1 maintenance outage were well managed on the whole. Technical incidents did however occur, particularly during requalification of the NPEs. The licensee must improve monitoring of the operations, particularly those involving significant radiological risks. As far as environmental protection is concerned, the site must improve its performance. Knowledge of the regulatory requirements considered as a whole remains insufficient and the organisational setup for the management of waste in the storage areas must be improved. Labour inspection in the nuclear power plants ASN conducted oversight actions concerning the conditions of health and safety during maintenance and construction operations and the management of subcontracting in the nuclear power plants. Following the fall of a steam generator on 31st March 2016 during its handling in reactor building 2 of the Paluel NPP, ASN examined the conditions of removal of this steam generator. ASN also conducted inspections on certain repair operations inside the reactor building, such as the repair work on the pool. Before the steam generator handling operations resumed, ASN required a third-party organisation check the conformity of the modified handling systems. Lastly, ASNmonitored resumption of the steam generator lifting operations in reactor building 2, which were completed in December 2017. Construction of the Flamanville 3 EPR reactor After issue of Creation Authorisation Decree 2007-534 of 10th April 2007 and the building permit, construction work began on the Flamanville 3 reactor in September 2007. The mechanical assembly work continued in 2017 with, for example, installation of the main secondary system equipment of the nuclear steam supply system, protection valves on the main primary system, reactor auxiliary systems, mechanical penetrations in the reactor containment, effluent treatment systems and the equipment necessary for the operation of the emergency diesel generator sets. Alongside this, the cable pulling and electrical connection operations have been stepped up. Lastly, the system start-up tests have entered an overall tests phase with the “primary system flushing” operations, part of the “functional tests with reactor vessel open” and starting of the “cold test 1 ” of the nuclear steam supply system. ASN carried out a specific inspection of these operations, and examined worker radiation protection, protection of the environment and preparation for reactor operation. ASN considers that the organisation put in place by EDF can be improved, particularly in the following areas: ཛྷ ཛྷ ensuring that the requirements specific to the break preclusion process are effectively taken into account before assembling the main secondary systems and correcting the significant deviations encountered in these activities, 1. Cold tests: these tests constitute the regulatory hydrostatic test of the main primary system.