France’s Nuclear Safety Authority (ASN) on 28 May published its report on nuclear safety and radiation protection in 2019.
It noted: “In a context where the level of safety of nuclear installations has remained generally satisfactory, 2019 was marked by greater awareness by nuclear operators of the challenges they face collectively.”
ASN said “the requirement of quality and rigour in the conduct of projects must be reaffirmed”, not only for new construction, but also for waste management, dismantling or major maintenance work.
The 393-page report covered every aspect of the French nuclear industry and its facilities including waste management and nuclear medicine. On nuclear power facilities it looked at currently operating reactors, and the EPR under construction at unit 3 of the Flamanville nuclear plant, as well as giving a brief consideration of future plans.
The report said continued operation of France’s 900MWe reactors are “an EDF objective that remains to be achieved”. ASN will assess the review of the 900MWe reactors at the end of 2020 and will adopt regulations relating to their continued operation. While modifications proposed by EDF signal significant improvements in the safety of the facilities and contributes to the achievement of the objectives of the review, “ASN considers that these modifications do not meet all of the objectives set. In the absence of the operator's additional proposals during 2020, ASN will prescribe additional modifications.”
On the faulty welds identified at the EPR under construction at Flamanville 3, the report said construction and manufacture of EPR equipment “have led to many deviations from quality expected, mainly due to loss of experience and lack of professional rigor, especially in the setting implementing special processes (welding, forging, processing thermal, non-destructive checks, etc.). These difficulties also revealed a failure in the surveillance by the operator.”
ASN noted that in 2018 it had recommended bringing them back into compliance while EDF had proposed “an approach aimed at justifying keeping certain welds in good condition”. ASN said: “Given the nature and particularly large number of deviations that occurred during the design and manufacture of these welds, and insofar as bringing them back into conformity is technically feasible, ASN indicated in June 2019 that their repair before putting the reactor into service was the benchmark solution.”
ASN said it considered that the organisation put in place for carrying out the start-up tests for the Flamanville 3 EPR reactor and the preparation for its operation was satisfactory in 2019. “Nevertheless, EDF must still complete its programme of additional controls carried out as part of the review of the quality of the equipment and implement it rigorously.” In addition, despite the mobilisation of resources and the significant improvement in the organisation of start-up tests, EDF must improve the management of control command and test configurations carried out on temporarily modified installations. It must also improve the use of accumulated feedback and the implementation of the necessary corrective actions. “Finally, EDF must ensure the application of a conservation, maintenance and testing strategy for the equipment and structures present on site until the reactor is commissioned.” In 2020, ASN said it will continue to monitor these issues.
On EDF’s plans for a new design EPR (EPR-NM), ASN said it “considers that the general safety objectives, the safety benchmark and the main options design are generally satisfactory” and had identified “the subjects to be investigated with a view to a possible request for authorisation to create a reactor”.
It specified: “Additional justifications are expected in particular on the approach to exclude rupture of primary and secondary main piping, the approach for taking account of attacks, in particular fire and explosion, and the design choices of certain safety systems.”
EDF will thus have to outline “the additional studies and justifications provided in response to this notice, as well as the modifications to the safety options that would result”.
On small modular reactors SMRs, ASN said: “A French SMR project bringing together EDF, Technicatome, CEA and Naval Group is currently at the stage of preliminary studies. ASN considers that these projects constitute opportunities to develop reactors presenting significant improvements in terms of nuclear safety.”
On generation IV reactors, ASN noted France’s participation in the Generation IV International Forum (GIF), but said: “Given the abandonment of the CEA's Astrid project, the industrial deployment of fourth generation reactors is envisaged at the earliest at the end of this century.”
The report said: “Faced with the prospect of the final shutdown of the two reactors at the Fessenheim nuclear power plant, then of several other reactors planned as part of the multi-year energy programme, ASN will be careful that the measures taken by the operators allow dismantling as quickly as possible. ASN will endeavour to optimise its investigation processes and draw all the lessons from the dismantling of the Fessenheim nuclear plant for the benefit of subsequent dismantling.”
Elsewhere it noted: “In general, the plan to dismantle the Fessenheim nuclear power plant sent by EDF is not sufficiently detailed for a facility as close to its final shutdown. ASN therefore asked EDF, in December 2019, to justify and further specify its strategy, in particular regarding the deadlines for dismantling operations and waste management.”
Photo: The report was presented to the Parliamentary Office For Scientific and Technological Assessment (OPECST) on 28 May (Photo: ASN)