ASN Report 2018

With a view to the continued operation of its reactors, the “major overhaul” programme and in the light of the lessons learned from the accident at the Fukushima NPP, ASN considers that it is important for EDF to continue with the efforts it has already begun in order to remedy the difficulties encountered and improve its maintenance programmes. ASN also observes shortcomings in the traceability and error-reduction measures concerning maintenance work. A number of anomalies are notably the result of incorrect application of a maintenance procedure, or even the inappropriate nature of the procedure itself. The workers still have to deal with constraints linked to work organisation, for which they are not responsible, such as insufficient preparation for certain activities, unplanned scheduling changes and problems with worksite coordination. The analyses carried out by the sites following significant events often lead to corrective measures that are no more than isolated awareness-raising sessions for staff, departments, or contractors identified as being responsible for the deviation. The analysis of the root causes must be taken further in order to identify any organisational weaknesses. ASN regularly notes EDF’s difficulty in ensuring appropriate and proportional monitoring of subcontracted activities, whether performed within the NPP itself or at the suppliers of goods and services. ASN however observes increased mobilisation by those responsible for monitoring outside contractors in the NPPs. It considers that EDF must further strengthen the role, the involvement and the competence of these persons, so that they can detect any inappropriate technical action at the earliest possible opportunity. Operation 2018 was marked by difficulties encountered by EDF during post-outage reactor restarts. The scheduling, performance and analysis of the results of periodic tests are areas in which virtually all the sites need to improve. More particularly, ASN’s inspectors on several occasions found incorrect conclusions regarding equipment availability following periodic testing. EDF has initiated improvement measures, the effects of which are not yet measurable. The management of certain sensitive activities, such as temporary system configuration changes in order to carry out periodic tests, would appear to be progressing on certain sites. This progress, which must be placed in the context of the action plans being run by EDF for several years now, still remains to be consolidated. In recent years, EDF has reinforced its organisation for managing hazard-related risks, such as the organisation put into place to detect and eliminate the risk of falling objects in the event of an earthquake (lighting, fire-fighting resources, etc.). However, ASN regularly observes that the steps taken by EDF to prevent hazards and mitigate their consequences need to be further improved. This is in particular the case with measures concerning the fire risk. In addition, the inspections of the emergency organisation and resources conf irmed that the organisation, preparedness and management principles for emergency situations covered by an On-site Emergency Plan (PUI) have been correctly assimilated. Continuation of reactor operations Finally, ASN notes the ambitious steps taken by EDF to enable its reactors to continue to operate. The steps planned as part of the fourth periodic safety review of the 900 MWe reactors will thus lead to significant improvements in the safety of the installations. ASN is however still waiting for additional demonstration data on certain subjects which, at this stage of the examination, could well lead to requests for significant additional measures. This is notably the case regarding seismic resistance, the efficiency of the systems recirculating the water present at the bottom of the reactor building sumps and the need or otherwise to increase the thickness of the basemat of certain containments. EDF deployed considerable engineering resources for this review. However, ASN found that the EDF engineering teams were saturated and this must be taken into account when preparing the other reviews. Personnel radiation protection and environmental protection In 2018, radiation protection was addressed differently by the various NPPs, notably with respect to radiological cleanness management within the facilities and the steps taken to prevent the risk of contamination. Faced with this situation, ASN is reinforcing its oversight of implementation of the action plans requested to correct these situations on the reactors concerned. EDF’s organisation for managing the detrimental effects and impact of NPPs on the environment needs to be improved on most sites and ASN considers that the licensee needs to raise its level of vigilance on these topics. Despite the action plan implemented by EDF to limit the incidents of liquid spillage into the environment, events leading to such spills were still too numerous in 2018. With regard to waste management, ASN observed progress by certain sites which had previously been under-performing, but still needs EDF to significantly improve its organisation on this topic. Individual NPP assessments The ASN assessments of each NPP are detailed in the Regional Overview in this report. Certain sites stand out positively: •  in the field of nuclear safety: Saint‑Alban/Saint-Maurice and Fessenheim; •  in the field of environmental protection: Paluel; •  in the field of radiation protection: Saint‑Alban/Saint-Maurice and, to a lesser extent, Blayais and Chinon. Other sites are on the contrary under-performing with respect to at least one of these three topics: •  in the field of nuclear safety: Civaux, Cruas, Golfech, Nogent- sur-Seine and, to a lesser extent, Belleville-sur-Loire; •  in the field of environmental protection: Blayais, Cruas, Dampierre-en-Burly, Gravelines and Nogent-sur-Seine; •  in the field of radiation protection: Cruas, Dampierre-en- Burly and Tricastin. ASN report on the state of nuclear safety and radiation protection in France in 2018  9