ASN Report 2021

Lastly, ASN considers that the proposed assumptions for evaluating the management of radioactive material and wastes are not sufficiently conservative. They do not systematically include either the management of legacy waste locations or the uncertainties regarding the management of LLW-LL waste. Similarly, the licensees tend to overestimate the prospects of reusing certain materials and to underestimate the actions necessary for bituminised waste. In 2021, ASN examined the update of these triennial reports and sent its observations to the Ministry responsible for the environment. 4 // Assessment of the licensees’ decommissioning strategies In a context in which numerous facilities have been shut down for several decades, with concomitant loss of knowledge of the facilities, ageing structures and in some cases large quantities of waste still present, the progress of decommissioning operations is one of the major issues for the safety of shut down facilities. Yet ASN has noted that the majority of these operations are falling significantly behind schedule. Consequently, every 10 to 15 years, ASN asks the CEA, EDF and Orano to present their decommissioning and radioactive waste management strategies, thereby providing an overall view of the decommissioning projects and the management routes necessary for removal of the radioactive waste resulting from the decommissioning operations. As far as decommissioning is concerned, the licensees must justify the priority operations, principally through safety analyses. This prioritisation provides a means of checking that even if some projects are substantially behind schedule the, the most significant resources will be devoted to operations with higher risk implications. With regard to radioactive waste management, ASN checks the consistency of the planned actions with the regulatory framework and the guidelines of the PNGMDR. The assessment of the radioactive waste management strategies is presented in chapter 14. 4.1 Assessment of EDF’s decommissioning strategy The first decommissioning strategy file for the EDF reactors definitively shut down (Chinon A1, A2, A3, Saint-Laurent A1 and A2, Bugey 1, EL4-D, Chooz A and Superphénix) was transmitted in 2001 at the request of ASN. Immediate dismantling was adopted as the reference strategy. This strategy has been updated regularly, in order to adjust the decommissioning schedule or incorporate the complementary studies requested by ASN and elements concerning the future decommissioning of the reactor fleet in service. For the six first-generation GCRs (Chinon A1-A2 and A3, Saint-Laurent A1 and A2 and Bugey 1), EDF informed ASN in March 2016 of a complete change in strategy calling into question the technique (“under water”) used for the decommissioning of these reactors and the rate of decommissioning, leading to the decommissioning of all the GCRs being pushed back by several decades. ASN will rule on the decommissioning time frames put forward by EDF in the decommissioning files submitted at the end of 2022, which may also be revised if it turns out in the coming decades that this scenario can be optimised in view of acquired experience. This decommissioning strategy for the GCRs is governed by two ASN resolutions, 2020-DC-0686 and CODEP-CLG-2020-021253, published on 3 March 2020. These resolutions establish the next steps necessary for the change in decommissioning strategy: submission of the decommissioning files corresponding to these new decommissioning techniques in late 2022, the defining of a robust waste management strategy, the decommissioning operations to be continued over the coming years, the commissioning of an industrial demonstrator in early 2022 and the information to be transmitted to ASN to monitor the effective implementation of the strategy. ASN considers that it is justified for EDF to develop an industrial demonstrator before decommissioning the reactor pressure vessels, but decommissioning of the various reactors must nevertheless begin within reasonable time frames in view of the obligation for decommissioning to be carried out as rapidly as possible. For the other shut down EDF facilities (notably Chooz A, AMI Chinon, EL4-D, Superphénix), decommissioning is under way and the requirement to ensure decommissioning in as short a time frame as possible is satisfied on the whole. 4.2 Assessment of Orano’s decommissioning strategy Decommissioning the old installations is a major challenge for Orano, which has to manage several large-scale decommissioning projects in the short, medium and long-term (UP2-400 facility at La Hague, Eurodif Production plant, individual facilities of the DBNI at Pierrelatte, etc.). Implementation of decommissioning is closely linked to the radioactive waste management strategy, given the quantity and the non-standard and hard to characterise nature of the waste produced during the prior operations phase and the new waste resulting from the decommissioning operations. Furthermore, Orano must carry out special WRP operations in old waste storage facilities. The deadlines for completion have been stipulated by ASN, particularly for the La Hague site. Completion of these WRP operations governs the progress of decommissioning on the UP2-400 plant, as WRP is one of the first steps of its decommissioning. The WRP work is of particular importance given the inventory of radioactive substances present and the age of the facilities in which they are stored, which do not meet current safety standards. In addition, WRP projects are considerably complex owing to the interactions with the plants in operation on the site. Further to the difficulties observed in the examination of files relating to the WRP and decommissioning operations at the Orano La Hague site and failure to perform the operations within the prescribed deadlines, ASN and Orano agreed to set up regular monitoring in order to foresee and address any blocking situations and determine practical measures to put in place to accomplish the WRP and decommissioning operations in the shortest time frame possible. In June 2016, at the request of ASN and the Defence Nuclear Safety Authority (ASND), Orano submitted its decommissioning and waste management strategy. The file also includes the application of this strategy on the La Hague and Tricastin sites. The Tricastin site accommodates one DBNI, hence the joint oversight of Orano by ASN and ASND (see “Notable Event” in the introduction to this report). ASN Report on the state of nuclear safety and radiation protection in France in 2021 339 13 – DECOMMISSIONING OF BASIC NUCLEAR INSTALLATIONS 08 07 13 04 10 06 12 14 03 09 05 11 02 AP 01

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