accounting system that tracks the entries into and exits from the La Hague plant. This system, called “EXPER”, was approved by the Order of 2 October 2008 of the Minister responsible for energy. The gaseous effluents are released mainly when the fuel assemblies are sheared and during the dissolution process. These gaseous effluents are treated by washing in a gas treatment unit. The residual radioactive gases, particularly krypton and tritium, are checked before being discharged into the atmosphere. The liquid effluents are treated and usually recycled. Some radionuclides, such as iodine and tritium, are channelled - after being checked – to the sea discharge outfall. This outfall, like the other outfalls of the site, is subject to discharge limits. The other effluents are routed to the site’s packaging units (solid glass or bitumen matrix). FINAL SHUTDOWN AND DECOMMISSIONING OPERATIONS ON CERTAIN FACILITIES The former Spent fuel reprocessing plant UP2‑400 (BNI 33) was commissioned in 1966 and has been definitively shut down since 1 January 2004. Final shutdown also concerns three BNIs associated with the UP2-400 plant: BNI 38 (which comprises the Effluents and solid waste treatment station No. 2 – STE2, and the Oxide nuclear fuel reprocessing facility No. 1 – AT1), BNI 47 (radioactive source fabrication unit – ELAN IIB) and BNI 80 (HAO facility). Orano submitted two partial decommissioning authorisation requests for BNIs 33 and 38 in April 2018. The schedule pushbacks requested by the licensee lead to decommissioning completion deadlines in 2046 and 2043 instead of 2035, the current deadline prescribed for the two BNIs. Further to Orano’s additions to the file concerning firstly the elimination of the interactions between the MAPu facility and the plutonium BST1 facility in the event of an earthquake, and secondly the memorandum in response to the opinion of the environmental authority, a public inquiry was held from 20 October to 20 November 2020. At the end of the inquiry, the inquiry commission issued a favourable opinion. ASN issued an opinion on the draft decrees in July 2022. Decrees 2022-1480 and 2022-1481 dated 28 November 2022 were published in the Official Journal of 29 November 2022. ASN notes that the schedule push-backs requested are significant and largely due to the delays in legacy Waste Retrieval and Conditioning (WRC). Consequently, ASN will continue to monitor the management of these projects in 2024. LEGACY WASTE RETRIEVAL AND CONDITIONING OPERATIONS Unlike the direct on-line packaging of the waste generated by the new UP2-800 and UP3-A plants at La Hague, most of the waste generated by the first UP2-400 plant was stored in bulk without permanent packaging. The operations to retrieve this waste are complex and necessitate the deployment of substantial means. They present major safety and radiation exposure risks, which ASN monitors with particular attention. The retrieval of the waste contained in the old storage facilities of the La Hague site is also a prerequisite for the decommissioning and clean-out of these facilities. Fission product evaporators-concentrators Six evaporators are used in facilities R2 and T2 to concentrate the fission product solutions before they undergo vitrification treatment. After measuring the thickness of the walls of these evaporators during the periodic safety reviews of the facilities as from 2012, a more advanced state of corrosion than predicted at the design stage was discovered. ASN therefore decided to regulate the continued operation of these evaporators in order to tighten their surveillance and to have additional means installed to mitigate the consequences in the event of a leak or rupture. In the course of this special surveillance, thickness measurements taken in September 2021 on evaporator 4120.23 of the T2 facility had shown that the operational criterion for shutting down the evaporator had been reached, which led Orano to decide not to restart the evaporator. To replace these evaporators, Orano is building new facilities baptised “New Fission Product Concentrations” (NCPF) and comprising six new evaporators. This project, which is particularly complex, has required several authorisations and was addressed by two ASN resolutions in 2021, concerning the active connection of the process of the three evaporators of NCPF T2 on the one hand and the three evaporators of NCPF R2 on the other. ASN issued the active commissioning authorisation for the NCPF T2 project on 16 September 2022. The T2 facility was shut down at the beginning of September 2022 in order to connect the new evaporators to the existing facilities and to continue the tests prior to commissioning, which took place in mid-April 2023, not significantly behind the initial schedule. In the context of this project, ASN conducted two inspections in 2022 concerning the tests carried out by the licensee and one inspection in February 2023. The NCPF R2 project is offset by about one year with respect to NCPF T2, meaning that the first tests were started at the end of 2022. The operations to connect the new evaporators to the existing facilities have been underway since October 2023, with commissioning scheduled for 2024. In the course of this project, ASN carried out one inspection relative to the tests performed by the licensee in 2023, which showed that the NCPF R2 project has effectively integrated the lessons learned from the NCPF T2 project. ASN will continue its inspection actions on the NCPF R2 project in 2024. NOTABLE EVENTS OF THE YEAR 2023 76 ASN Report on the state of nuclear safety and radiation protection in France in 2023 Regional overview of nuclear safety and radiation protection • NORMANDIE •
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