Abstracts ASN Report 2019

Professional competence and rigour at the heart of the nuclear industry’s recovery At the end of 2018, ASN underlined the need for re-engagement by the nuclear industry in order to maintain the key industrial skills vital to the quality of the work done and the safety of the facilities. In 2019, in response to a request from the Government and further to the conclusions of the ɖǣǼƳǣȇǕ Ɏǝƺ IǼƏȅƏȇɮǣǼǼƺ ڳ 0¨« report by Jean-Martin Folz, EDF presented an action plan “ to restore the level of quality, rigour and excellence which underpinned the construction of the French NPP fleet ”. ASN considers that the orientations of the plan are a step in the right direction. Quality and professional rigour are key aspects in ensuring the safety of the facilities. They must be applied both in the performance of the activities and in their oversight by the licensees, who hold prime responsibility for safety. ASN considers that the commitment to quality and rigour in running projects must be restated, not only for new constructions, but also for legacy waste recovery and packaging projects, decommissioning, or major maintenance works. The nuclear industry must more precisely define the conditions for implementation of this action plan, notably in terms of reinforcing the safety culture and a rigorous professional attitude. Continued operation of the 900 MWe reactors: an EDF goal still to be achieved With the support of the IRSN, ASN continued to examine the fourth periodic safety review of the 900 MWe reactors, in order to define the generic conditions for their continued operation, in other words those that are applicable to all these reactors. The main goals of this review concern the management of installation conformity, more particularly ageing management, as well as the facility’s greater robustness to natural hazards and the mitigation of the radiological consequences in the event of an accident, notably with core melt. These goals were defined in the light of the safety objectives set for the third generation reactors, in particular the EPR. For the fourth periodic safety review, EDF proposed installation modifications in order to achieve these goals, for example to improve the safety of the spent fuel pool, or to reduce the risk of containment basemat melt-through with the resulting contamination of the soil and groundwater in the event of an accident with core melt. ASN will issue a resolution on the generic part of the periodic safety review of these reactors at the end of 2020, to regulate their continued operation. ASN considers that implementation of the modifications proposed by EDF leads to significant safety improvements for the facilities and contributes to achieving the goals of the periodic safety review. However, at this stage of the examination, ASN considers that these modifications alone are unable to meet all the targets set. In the absence of any additional proposals from the licensee during the course of 2020, ASN will prescribe additional modifications. In 2019, Tricastin reactor 1 was the first to carry out its fourth ten-yearly outage. EDF set up a specific organisation and extensively mobilised its national engineering division to provide the site with support, before and during the outage, so that the modifications to be deployed could be fully assimilated. This organisation enabled the work to be carried out satisfactorily. ASN underlines the fact that over the next few years several reactor ten-yearly outages will be performed at the same time and queries EDF’s ability to implement such an organisation simultaneously on the sites concerned. Questions about the operational intervention conditions During its inspections, ASN placed greater emphasis on controlling the implementation of the operational measures planned by the licensees to deal with undesirable events in a nuclear facility. In this respect, ASN conducted exercises simulating an outbreak of fire, internal flooding, loss of containment of hazardous products, or an accident situation. For certain exercises, ASN observed that the actions required in these situations were not feasible or that the intervention times were longer than those planned by the licensee. These findings mean that the licensee must ensure that the actions required by the operating documents are actually operationally feasible and take corrective measures where applicable. More generally, the growing complexity of the rules to be followed and of the operational measures to be taken, demands extra vigilance on the part of all the players. The eight EPR containment penetration welds to be repaired The Flamanville EPR reactor is a pressurised water reactor, providing a significantly higher level of safety than the reactors currently in operation. The EPR in particular offers greater protection against external hazards and more effective means of mitigating the consequences of accidents with core melt. Numerous deviations from the expected quality were found in the construction and manufacture of the EPR equipment, primarily due to a loss of experience and a lack of professional rigour, notably in the use of special processes (welding, forging, heat treatment, non-destructive testing, etc.). These problems also revealed shortcomings in the oversight exercised by the licensee. ASN Report on the state of nuclear safety and radiation protection in France in 2019 3 COMMISSION EDITORIAL