ASN Report 2020

In France, the authorisation to create a nuclear facility is issued by the Government, after consulting ASN. This author­ isation is issued without time limit. An in-depth examination, called the “periodic safety review”, is performed every 10 years to evaluate the conditions for the continued operation of the installation for the next 10 years. EDF’s 32 reactors of 900MWe are the oldest reactors in operation in France. Their 4th periodic safety review is of particular significance, because their design postulated an operating lifetime of 40 years. Their continued operation beyond this period requires the updating of design studies and equipment replacements. ASN underlines the ambitious objectives of the 4th peri- odic safety review of the 900MWe reactors and the substan- tial work carried out by EDF in the generic phase. It also underlines the scale of the modifications planned by EDF, the implementation of which will bring about significant safety improvements. The periodic safety review determined a roadmap for the specified safety improvements These improvements more particularly concern control of the risks associated with hazards (fire, explosion, flooding, earthquake, etc.), the safety of the spent fuel storage pool and the management of core meltdown accidents. In its resolution 2021-DC-0706 of 23 February 2021, ASN required the implementation of the major safety improve- ments planned by EDF, along with additional measures it considers necessary to achieve the objectives of the periodic safety review. This resolution closes the “generic” phase of the periodic safety review, which concerns the studies and modifications of the installations common to all the 900MWe reactors, as they are all based on a similar design. The measures planned at the generic stage of the periodic safety review and those that will be defined in the studies specific to each site, will have to be applied on each reac- tor with a view to its continued operation. ASN asks EDF to carry out the majority of the safety improvements before submitting the periodic safety review concluding report, and in practice during the 10-yearly outage of each reactor. The other improvements shall be carried out within a maximum of 5 years after submitting this report. This time is increased to 6 years for the first reactors, that is: Tricastin 1 and 2, Bugey 2, 4 and 5, Gravelines 1 and Dampierre 1. This phased approach is linked to the scale of the works on each reactor, which will moreover be carried out concurrently on several 900MWe reactors. It takes account of the ability of industry to conduct the works with the required standard of quality and the associated operator training necessary so that they can familiarise themselves with these changes. Conditions for the continued operation of the 900MWe reactors ASN has completed its examination of the generic phase of the 4th periodic safety review of the 900MWe reactors. ASN considers that all the provisions specified by EDF and those that it itself requires, open up the prospect of continued operation of the 900 MWe reactors for the ten years following their 4th periodic safety review. Tricastin Nuclear Power Plant (NPP) 24 ASN Report on the state of nuclear safety and radiation protection in France in 2020 NUCLEAR POWER PLANTS BEYOND 40 YEARS