Abstracts ASN Report 2021

In a letter dated 22 June 2017, EDF declared final shutdown of the BCOT in June 2020. The storage activities and maintenance operations are now carried out in its Saint-Dizier maintenance base. The last operating activity consisted in finishing cutting up the used fuel cluster guide tubes from the PWRs operated by EDF. The facility is now being prepared for decommissioning, for which the review procedure is in progress. ASN considers that the level of safety of the BCOT is satisfactory. ROMANS-SUR ISÈRE SITE On its Romans‑sur‑Isère site in the Drôme département, Framatome operates BNI 63-U, baptised “Nuclear fuel fabrication plant” resulting from the merging of two BNIs, namely the Unit fabricating fuel elements for research reactors (formerly BNI 63) and the Unit fabricating nuclear fuel for the PWRs (formerly BNI 98). Framatome nuclear fuel fabrication plants The fabrication of fuel for electricity generating reactors involves the transformation of UF6 into uranium oxide powder. The pellets fabricated f rom this powder in Framatome’s Romans‑sur‑Isère plant, called “FBFC” (formerly BNI 98), are placed in zirconium metal clads to constitute the fuel rods, then brought together to form the assemblies for use in the NPP reactors. In the case of experimental reactors, the fuels used are more varied, with some of them using, for example, highly-enriched uranium in metal form. These fuels are also fabricated in the Romans‑sur‑Isère plant, called “Cerca” (formerly BNI 63). The former BNI 63 includes building F 2, which houses the “uranium zone” where compacted powder cores placed in aluminium frames and plates are produced. The licensee has undertaken to replace this uranium zone by a new uranium zone called “NZU”, in order to improve more specifically the containment of the premises, the process and the prevention of risks in the event of an extreme earthquake. The NZU construction work began in late 2017. These new buildings shall accommodate the current activities of the uranium zone of building F 2 before 31 December 2022. This is because as from that date, which is stipulated in ASN resolution 2019‑DC‑0670 of 4 June 2019 relative to the periodic safety review of former BNI 63, the presence of radioactive substances in the uranium zone of building F 2 shall be prohibited. Construction of the NZU continued in 2021, notably with the manufacture and installation of new equipment and performance of the f irst operating tests. The update of the safety report and the new general operating rules associated with the NZU were submitted to ASN in the f irst half of 2021, leading to complementary information requests on its part. A request for a modification of the Order of 22 June 2000 governing water intakes, discharges and environmental monitoring of the Romans‑sur‑Isère nuclear site was also submitted to ASN in July 2020. This request follows on from several changes, including in particular the modification of the DAC of former BNI 98 to increase its production capacity, the stopping of certain activities, the taking into account of the changes made to the liquid effluent treatment facilities, and the changeover from continuous discharging of liquid effluents to discharging into tanks. This file will give rise to the publication of two ASN resolutions: the f irst stipulating the requirements relative to the conditions of effluent discharge, water intakes and consumption and environmental monitoring, the second stipulating the environmental discharge limits. The draft resolutions were made available for public consultation from 14 July to 29 August 2021. By a resolution of 20 December 2021, ASN authorised the “Training, Research, Isotopes, General Atomics” (TRIGA) unit, intended for the production of fuels for american-designed research reactors, to be put back into operation. A substantial modif ication request submitted for former BNI 98 in December 2020 aims to allow increased production of fuels based on enriched reprocessed uranium. It is currently being examined. Given that the buildings of former BNIs 98 and 63 are very closely interlinked on the same site, a request to unite the two BNIs was submitted in 2020. On 23 December 2021, the two BNIs were merged by Decree 2021‑1782 into a single BNI 63-U, called “Nuclear fuel fabrication plant”. Six signif icant events relating to control of the criticality risk and rated level 1 on the INES scale by Framatome were reported in 2021. These events are not inter-related and concern both BNIs. ASN performed a reactive inspection for two of these events and remains vigilant regarding the implementation of effective measures to prevent such events from recurring. The inspections performed in 2021 conf irmed the integrity of the facilities during the summer works and compliance with commitments, particularly concerning the control of maintenance. However, the inspection concerning the checking of laboratory L1’s approval for taking environmental radioactivity measurements highlighted shortcomings for which the licensee established a major action plan. These improvements were verif ied in the last quarter of 2021 with satisfactory conclusions through an unannounced inspection. ASN will be attentive to the progress of the NZU construction site in 2022, and to maintaining operating rigour and deploying a good questioning attitude, a guarantee of operational safety, in a context of major movements within the safety and radiation protection teams and continuation of the modifications to the facilities. Furthermore, the waste management rules must continue to be applied and brought to people’s attention in the various facilities of the site. ABSTRACTS – ASN Report on the state of nuclear safety and radiation protection in France in 2021 47 REGIONAL OVERVIEW OF NUCLEAR SAFETY AND RADIATION PROTECTION AUVERGNE-RHÔNE-ALPES