Abstracts ASN Report 2019

ASN added to its requests with a range of resolutions dated Ӆӄׇ ĴŁňĴŅŌ ӅӃӄӇׇĴļŀļŁĺ Ňł ĶĿĴŅļĹŌ ĶĸŅŇĴļŁ ķĸņļĺŁ ŃŅłʼnļņļłŁņ ĹłŅ ŇĻĸ “hardened safety core”, in particular the definition and justification łĹ ŇĻĸ ĸŋŇŅĸŀĸ ĸŋŇĸŅŁĴĿ ŁĴŇňŅĴĿ ĻĴōĴŅķ ĿĸʼnĸĿņ Ňł ĵĸ ĶłŁņļķĸŅĸķ ĹłŅ the “hardened safety core”. More generally, ASN’s requests are also part of a continuous process to improve safety with regard to the targets set for the 3rd-generation reactors, and aim in addition to be able to cope with situations far beyond those normally considered for this type of installation. These requests are issued in application of the defence-in-depth approach and as such concern measures to prevent and mitigate the consequences of an accident, based on both additional fixed means and external mobile means planned for all the installations on a site beyond their initial design basis. Given the nature of the works requested, the licensee must carry out studies for the design, construction and installation of new equipment which first of all require time and secondly a schedule to optimise their implementation on each NPP. Indeed, insofar as these major works are carried out on nuclear sites which are in service, it is also necessary to ensure that their performance does not degrade the safety of the NPPs. Ł ӅӃӄӈё ĶłŀŃĿĸŇĸķ ŇĻĸ ķĸŃĿłŌŀĸŁŇ łĹ ŇĸŀŃłŅĴŅŌ łŅ ŀłĵļĿĸ measures to enhance how the main situations of total loss of the heat sink or electrical power supplies are addressed. More particularly, connection means were installed so that, in the event of an emergency, the mobile systems can be connected to ŃŅłʼnļķĸ ŊĴŇĸŅє ňŅŇĻĸŅŀłŅĸё ŇĻĸ ё ŊĻļĶĻ ļņ łŁĸ łĹ ŇĻĸ ŀĴļŁ ĸŀĸŅĺĸŁĶŌ ŀĴŁĴĺĸŀĸŁŇ ŀĸĴŁņё ŊĴņ ņĸŇ ňŃє ļŁĶĸ ӆӄׇ ĸĶĸŀĵĸŅ ӅӃӄӈё ŇĻĸ ŇĸĴŀņ ĻĴʼnĸ ĻĴķ ŇĻĸ ĶĴŃĴĶļŇŌ ĹłŅ ņļŀňĿŇĴŁĸłňņ ļŁŇĸŅʼnĸŁŇļłŁ łŁ ĴĿĿ ŇĻĸ ŅĸĴĶŇłŅņ łĹ Ĵ ņļŇĸ ļŁ Ŀĸņņ ŇĻĴŁ ӅӇׇĻłňŅņ ҎňŃ Ňł six reactors in the case of the Gravelines site). These provisions are in response to the recommendations resulting from the European ŃĸĸŅ ŅĸʼnļĸŊ ļŁ ŃŅļĿ ӅӃӄӅׇĴņ ŃĴŅŇ łĹ ŇĻĸ ňŅłŃĸĴŁ ņŇŅĸņņ ŇĸņŇņє ĻĴņ ĴĿņł ņŇĴŅŇĸķ ŇĻĸ ķĸŃĿłŌŀĸŁŇ łĹ ĶĸŅŇĴļŁ ŃĸŅŀĴŁĸŁŇ resources robustly designed and organised with regard to extreme ĻĴōĴŅķņ ļŁ łŅķĸŅ Ňł ķĸĴĿ ŊļŇĻ ŇĻĸ ŀĴļŁ ņļŇňĴŇļłŁņ łĹ Ŀłņņ łĹ ĻĸĴŇ sink or of electrical power supplies beyond the safety baselines currently in force and core melt accidents. The most important measures are: Ҋ installation of a large-capacity Ultimate Backup Diesel- generator set (DUS), requiring the construction of a dedicated building to house it; owing to the industrial difficulties ĸŁĶłňŁŇĸŅĸķ ĵŌ ļŁ ŇĻĸļŅ ĶłŁņŇŅňĶŇļłŁё ķĸĶļķĸķ ļŁ ӅӃӄӌׇŇł ŀłķļĹŌ ŇĻĸ ņĶĻĸķňĿĸ ĹłŅ ĶłŀŀļņņļłŁļŁĺ ŇĻĸņĸ є Ł parallel with this rescheduling, with the deadline now being set ĴŇ ӆӄׇ ĸĶĸŀĵĸŅ ӅӃӅӃё ļņņňĸķ ĵļŁķļŁĺ ŅĸńňļŅĸŀĸŁŇņ ĹłŅ ĴŁ increase in the robustness of the existing electricity sources. Ň ŇĻĸ ĸŁķ łĹ ӅӃӄӌё ӆӈׇ ĻĴķ ĵĸĸŁ ĶłŀŀļņņļłŁĸķ ĵŌ ђ Ҋ ŇĻĸ ĶŅĸĴŇļłŁ łĹ ĴŁ ňĿŇļŀĴŇĸ ŊĴŇĸŅ ņłňŅĶĸє ņ ĴŇ ӆӄׇ ĸĶĸŀĵĸŅ ӅӃӄӌё ĻĴņ ņĸŇ ňŃ ŇĻĸ ňĿŇļŀĴŇĸ ŊĴŇĸŅ ņłňŅĶĸ łŁ ŇĻĸ ĿĴŀĴŁʼnļĿĿĸ ņļŇĸє ĴĿņł ļŁļŇļĴŇĸķ ŇĻĸ ĶŅĸĴŇļłŁ łĹ ŇĻĴŇ łŁ other sites and plans to complete the works at the end of 2021, except for the Blayais, Gravelines and Dampierre-en-Burly sites, for which the work will be completed in 2022; Ҋ construction on each site of a local emergency centre capable łĹ ŊļŇĻņŇĴŁķļŁĺ ĸŋŇŅĸŀĸ ĸŋŇĸŅŁĴĿ ĻĴōĴŅķņ ҎĹňŁĶŇļłŁĴĿĿŌ ļŁķĸŃĸŁķĸŁŇ ļŁ ĴŁ ĸŀĸŅĺĸŁĶŌ ņļŇňĴŇļłŁҏє Ł ӅӃӄӌё completed the construction of the local emergency centre on ŇĻĸ ĿĴŀĴŁʼnļĿĿĸ ņļŇĸё ŊĻļĶĻ ņĻłňĿķ ĵĸ ĶłŀŀļņņļłŁĸķ ļŁ ӅӃӅӃє łŅ ŇĻĸ łŇĻĸŅ ņļŇĸņё ŃĿĴŁņ ĶłŀŃĿĸŇļłŁ łĹ ŇĻĸ ŊłŅľņ ĵĸŇŊĸĸŁ ӅӃӅӅׇĴŁķ ŀļķіӅӃӅӈє These measures will also be supplemented during the periodic safety reviews by implementation of the “hardened safety core”. These resources were partially deployed on the Tricastin NPP ŅĸĴĶŇłŅ ӄׇķňŅļŁĺ ļŇņ ĹłňŅŇĻ ŇĸŁіŌĸĴŅĿŌ ļŁņŃĸĶŇļłŁє The most important measures are: Ҋ addition of a new makeup pump to the primary system; Ҋ completion of the fixed connection systems for the SG backup feedwater supply, the PTR cooling water tank and the spent fuel pit; Ҋ installation of an ultimate instrumentation & control system and the definitive instrumentation of the “hardened safety core”; Ҋ installation of a reactor containment ultimate cooling system that does not require opening of the containment venting- filtration system in the event of a severe accident; Ҋ the installation of a corium flooding solution which would be installed in the reactor pit, to prevent basemat melt-through in the event of core melt. In anticipation of setting up the “hardened safety core”, ASN is examining the design hypotheses for the material provisions ĴŁķ ĶĻĸĶľļŁĺ ŇĻĴŇ ŇĻĸ ņłĿňŇļłŁņ ŃŅłŃłņĸķ ĵŌ ĶĴŁ ŀĸĸŇ ŇĻĸ safety objectives set. Ł ŇĻĸ ĵĴņļņ łĹ ŇĻĸ ĹļĿĸņ ŇŅĴŁņŀļŇŇĸķ ĵŌ ĴŁķ ŇĻĸ ņŇňķļĸņ carried out, ASN asked the Advisory Committee for Reactors (GPR) for its opinion on the more important points of these files. To date, three meetings of the GPR have been held: Ҋ Ļĸ ŊĴņ ĶłŁņňĿŇĸķ łŁ ӅӋׇ ĴŁňĴŅŌ ĴŁķ ӄӃׇ ĸĵŅňĴŅŌ ӅӃӄӉ concerning the definition and justification of the natural ĻĴōĴŅķ ĿĸʼnĸĿņ ĴķłŃŇĸķ ĵŌ ĹłŅ ŇĻĸ ѢĻĴŅķĸŁĸķ ņĴĹĸŇŌ ĶłŅĸѣє Ļļņ ŅĸʼnļĸŊ ĴĿĿłŊĸķ ŇĻĸ ķĸĹļŁļŇļłŁ łĹ ŇĻĸ ĻĴōĴŅķ ĿĸʼnĸĿņ Ňł ĵĸ considered for the design of the “hardened safety core” and, łŁ ĶĸŅŇĴļŁ ŃłļŁŇņё Ŀĸķ Ňł Ĵņľ ĹłŅ ĶĿĴŅļĹļĶĴŇļłŁє Ҋ Ļĸ ņĸņņļłŁ łĹ ӊׇ ňĿŌ ӅӃӄӉׇĶłŁĶĸŅŁĸķ ŇĻĸ ŁĸŊ ŃŅłʼnļņļłŁņ ŃŅłŃłņĸķ ĵŌ Ňł ŀļŇļĺĴŇĸ ŇĻĸ ņĻłŅŇ ĴŁķ ĿłŁĺ ŇĸŅŀ consequences of a core melt accident. This review enabled ASN to validate the principle of the new measures proposed ĵŌ ļŁ łŅķĸŅ Ňł ŀļŇļĺĴŇĸ ŇĻĸ ĶłŁņĸńňĸŁĶĸņ łĹ Ĵ ĶłŅĸіŀĸĿŇ ĴĶĶļķĸŁŇє Ł ĶĸŅŇĴļŁ ŃłļŁŇņё Ĵņľĸķ ĹłŅ ĶĿĴŅļĹļĶĴŇļłŁņ and additional studies. Ҋ Ļĸ ņĸņņļłŁ łĹ Ӆׇ ĸĵŅňĴŅŌ ӅӃӄӊׇĹłĶňņĸķ ŃŅļŀĴŅļĿŌ łŁ ŇĻĸ strategies for management of accidents that can occur on the reactor and pool and on the functional adequacy of the (new or existing) equipment for these accidents. ³z ǣȇɀȵƺƬɎǣȒȇ ƏɎ Ɏǝƺ !ǝȒȒɿ z¨¨ ٫ 0ȇɎƺȸǣȇǕ Ə ƬȒȇɎȸȒǼǼƺƳ ƏȸƺƏ 302 ASN Report on the state of nuclear safety and radiation protection in France in 2019 ׏׎ ٲ THE EDF NUCLEAR POWER PLANTS