Abstracts ASN Report 2021

of the starting of this plant’s support functions. Trident, the new waste treatment unit of BNI 138 also gradually started operating in 2021. Construction of “FLEUR”, the new reprocessed uranium storage facility, began at the same time as the examination of its license. Lastly, ASN continued examination of the creation authorisation application for the future containers maintenance unit (AMC2). It will take over from the existing unit (AMC), which is to stop operating in 2024. This authorisation application was the subject of a public inquiry from 10 December 2021 to 12 January 2022. In 2021, ASN conducted a campaign of simultaneous unannounced inspections in BNIs 93, 105, 138, 155, 168 and 178 focusing on the periodic inspections and tests and maintenance, with the aim of checking Orano’s organisation in these areas. The inspectors were thus able to attend more than ten periodic inspections and tests or maintenance operations and visit the spare parts stores. The overall assessment of these inspections is satisfactory. Orano has submitted to ASN its strategy for changing the industrial scheme for managing all the site’s liquid effluents. ASN has set up regular monitoring of implementation of this strategy, which is necessary to plan ahead for the technical developments. To check the progress of treating the backlog of diverse radioactive substances stored on the site, ASN has also asked Orano to present an annual statement on the progress of its action plan for the treatment of these substances. In 2022, ASN will also ensure that Orano improves its organisation for analysing the conformity of the facilities with the regulations and further improves its follow-up of the commitments made to ASN. Orano uranium chemistry plants TU5 and W BNI 155, called TU5, can handle up to 2,000 tonnes of uranium per year, which enables all the uranyl nitrate (UO2(NO3)2) from the Orano plant in La Hague to be processed for conversion into U3O8 (a stable solid compound that can guarantee storage of the uranium under safer conditions than in liquid or gaseous form). Once converted, the reprocessed uranium is placed in storage on the Tricastin site. The W plant situated within the perimeter of BNI 155 can process the depleted UF6 from the Georges Besse II plant, to stabilise it as U3O8. ASN considers that the safety of operation of the facilities situated within the perimeter of BNI 155 is satisfactory, but it notes an increase in significant events related to occupational radiation protection. For the TU5 plant, ASNmade public its analysis of the facility’s periodic safety review report in 2021. It is continuing to check implementation of the commitments made in this context. ASN will be attentive to the licensee’s actions in 2022 on the theme of the safety and radiation protection culture and will remain vigilant with regard to maintaining sufficient rigour in the operation and maintenance actions and in the monitoring of detected deviations. Orano uranium fluorination plants Pursuant to the ASN requirement, the oldest fluorination facilities were shut down def initively in December 2017. The shut down facilities have since been emptied of the majority of their hazardous substances and are now in the decommissioning preparation phase. The decommissioning of BNI 105 is authorised by Decree 2019-1368 of 16 December 2019. The main issues associated with decommissioning concern the risks of dissemination of radioactive substances, of exposure to ionising radiation and of criticality, on account of the residual uranium-bearing substances present in some items of equipment. In 2021, ASN also inspected the continuation of the upgrading of the Philippe Coste plant, whose facilities are classif ied Seveso high threshold and replace those of BNI 105 (formerly Comurhex). The main units of this plant were commissioned in 2019, but in 2020 the licensee had to replace all the crystallising containers and solve various technological diff iculties. This upgrading of the process core restored more stable and therefore safer functioning in 2021, producing fewer minor atmospheric discharges associated with operating transients. The new fluorine production unit has also been commissioned. ASN will be attentive in 2022 to the maintaining of operating conditions, particularly those of the old conversion effluent treatment units. This is because the new effluent treatment unit of the Philippe Coste plant has to be modified in depth and will not be available for several years. Furthermore, as regards the shut down facilities, ASN considers that the package repackaging projects have not made sufficient progress and expects the licensee to make greater efforts to ensure the repackaging of the packages containing radioactive and hazardous substances on areas 61 and 79 within the assigned times. Georges Besse I enrichment plant The Georges Besse I (Eurodif) uranium enrichment facility, constituting BNI 93, consisted essentially of a plant for separating uranium isotopes by the gaseous diffusion process. After stopping production at this plant in May 2012, the licensee carried out, from 2013 to 2016, the Eurodif “Prisme” process of “intensive rinsing followed by venting”, which consisted in performing repeated rinsing of the gaseous diffusion circuits with chlorine trifluoride (ClF3), a toxic and dangerous substance. These operations, which are now completed, allowed the extraction of virtually all the residual uranium deposited in the diffusion barriers. The licensee submitted its application for final shutdown and decommissioning of the facility in March 2015. The Decree ordering Orano to proceed with the decommissioning of the Georges Besse 1 plant was published on 5 February 2020. The decommissioning issues particularly concern the large volume of very low-level waste (VLLW) produced, including 160,000 tonnes of metal waste which are undergoing ABSTRACTS – ASN Report on the state of nuclear safety and radiation protection in France in 2021 45 REGIONAL OVERVIEW OF NUCLEAR SAFETY AND RADIATION PROTECTION AUVERGNE-RHÔNE-ALPES

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