ASN Report 2017

206 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 08  - Regional overview of nuclear safety and radiation protection With regard to EM3, the new uranium hexafluoride (UF 6 ) emission unit of the W plant, which is scheduled for commissioning in 2018, the work has continued with the completion of equipment installation and starting of tests. This new unit will meet the safety requirements set by ASN in the wake of the Fukushima nuclear accident and will ensure better containment in the event of a UF 6 leak and greater resistance to internal and external hazards. More generally, the licensee must continue to improve operating rigour and more specifically the detection and management of deviations. ASN will therefore remain attentive to see that sufficient rigour is maintained in the operating and maintenance actions, in the management of anomalies detected during the periodic verifications and tests and in the tracking of deviations and the resulting actions. In addition to this, an unannounced inspection on waste management revealed that Areva was not adequately organised to process the large streams of waste during technical outages and to ensure compliance with the interim storage management requirements and the segregation, packaging and traceability of the different categories of waste. ASN asked for a plan of action combined with verification and monitoring measures to be put in place; it will check the results of this in 2018. Areva’s uranium fluorination plants in Pierrelatte (Drôme département ) The functioning of the Comurhex 1 fluorination plant was affected by several unforeseen events in 2017. Several events – with no off-site consequences – were notified further to nonconforming discharges and losses of containment, particularly the dispersion of potash that was slightly contaminated with uranium over the facility. In accordance with the ASN requirement, the plant definitively stopped production before 31st December 2017. In October 2017, ASN actually suspended operation of the plant further to anomalies affecting the embankment protecting the site from the Donzère-Mondragon Canal. ASN prescribed the reinforcement of the water curtain systems designed to mitigate the consequences of a discharge of gaseous hydrofluoric acid, so that they remain operational in the event of a flood resulting from a breach in the embankment caused by an earthquake. At the same time, the licensee has made significant progress in the tests of the new Comurhex 2 production units, which will start production in 2018 to reach nominal level in 2019. ASN will be watchful to ensure that the licensee draws the lessons from the operation of the Comurhex 1 plant to establish a high level of operating rigour in the Comurhex 2 plant. Alongside this, the licensee continued its programme to prepare for final shutdown of the old installations of BNI 105, prior to their decommissioning. ASN discovered an unsatisfactory situation in a legacy storage area on the site and asked that a plan of action be implemented to improve the safety of this storage area until the material it contains is removed. ASN continued the examination of the decommissioning file. The file was submitted to a public inquiry in early 2017 and the decommissioning decree should be signed in 2018. Eurodif’s Georges Bess I enrichment plant in Pierrelatte (Drôme département ) The gaseous diffusion rinsing of the enrichment cascade equipment at the Georges Besse I plant was finished at the end of 2015 and achieved the uranium-removal objectives for the circuits and diffusers under conditions of safety deemed satisfactory by ASN. Operations to prepare for the decommissioning phase have been in progress since 2017. The licensee has submitted to ASN an authorisation file for the shut down facilities to enter a monitoring phase which is to last until the start of the decommissioning operations, scheduled as from 2028. Before issuing its authorisation, ASN asked the licensee to draw up a precise inventory of the last potential risks, which arise in particular from the operational waste that remains to be removed. The licensee must also continue removing this waste and treating the residual pollution of the facilities. Following a fire response exercise which was organised during an unannounced inspection and which put Eurodif in difficulty, ASN obtained the reinforcement of the response team that intervenes in the event of fire in these facilities. Furthermore, following the discovery in 2016 of shortcomings in waste management, radiation protection and environmental protection, ASN notes that in 2017 Eurodif put in place many measures to improve these issues. ASN notes in particular the action plan deployed to improve the monitoring of the areas delegated to the joint services of the Areva Tricastin platform. Alongside this, a procedure to modify the authorisation decree is in progress to provide a framework for the decommissioning of the facility. The licensee’s file underwent a public inquiry in early 2017. The decommissioning challenges concern the volume of waste produced (including 160,000 tonnes of metallic waste) and the decommissioning time frame which must be as short as possible (currently estimated at 30 years). ASN will issue a position statement on this file in 2018. SET’s Georges Bess II enrichment plant in Pierrelatte (Drôme département ) The Georges Besse II (GB II) plant operated by Société d’Enrichissement du Tricastin (SET), displayed a satisfactory level of safety in 2017. The technologies utilised in the facility enable high targets for safety, radiation protection and environmental protection to be achieved. Ramping the plant up to full production was slowed down to maintain the skills currency of the centrifuge installer’s teams. It was completed at the end of 2017. ASN identified in 2017 two areas requiring particular attention. The first concerns the discovery of a water presence detector which was not connected to the instrumentation and control system, an anomaly which had failed to be detected by both the commissioning tests and the periodic tests. The second AUVERGNE-RHÔNE-ALPES