ASN Report 2020

of the waste produced during the prior operations phase and the new waste resulting from the decommissioning operations. Furthermore, Orano must carry out special legacy Waste Retrieval and Packaging (WRP) operations in old waste storage facilities. The deadlines for completion have been stipulated by ASN, particularly for the La Hague site. Furthermore, 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. WRP projects are becoming increasingly complex owing to the interactions with the plants in operation and the site. In June 2016, at the request of ASN and 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, which mobilised substantial expertise for the joint examination of this strategy. The two Authorities consider that Orano must increase its ability to prioritise the operations according to the risks inherent to the facilities to decommission and to control the time frames. In addition, Orano’s human and technical resources must also be increased in order to meet the deadlines for the operations. 6. The Potential Source Term (“TSM” from the French “Terme source mobilisable”) corresponds to the quantity of radioactive activity that could be involved in an incident or accident. It is defined from the “source term” (activity of all the radioactive substances present in the facility) weighted by factors linked to: - the dispersibility of the matrix (according to whether or not the radioactive substances are blocked in the materials and the nature of the blocking matrix), - the effectiveness of the containment barriers (according to the seismic strength of the building and whether or not the ventilation is operational), - the susceptibility of the source term to external hazards (the accident scenario adopted is an earthquake combined with a fire), - the radiotoxicity of the inventory ( β - γ , tritium or α spectrum). 4.3  Assessment of the CEA’s decommissioning strategy Given the number and complexity of the operations to be carried out for all the nuclear facilities concerned, CEA is giving priority to reducing the “Potential Source Term” (TSM (6) ) which is currently at a very high level in certain facilities, in particular in some of the individual facilities of the Marcoule DBNI and in BNIs 72 and 56. In their position statement letter of 27 May 2019, ASN and the ASND considered that, given the resources allocated by the State and the large number of facilities undergoing decommissioning, for which legacy waste retrieval and storage capacity will need to be built, it was acceptable for the CEA to envisage staggering the decommissioning operations and that priority be given to those facilities in which the safety issues were greatest. The Authorities have since observed changes in the WRP schedules presented by the CEA, particularly the pushing back of waste management deadlines, including for operations considered to be priorities. ASN, ASND and the DGEC shall be attentive to this in 2021 when examining the files submitted by the CEA, and will check the progress of the priority operations, particularly by conducting targeted inspections on the management of the WRP and decommissioning projects of the abovementioned facilities. As concerns lower priority facilities, ASN and ASND also noted in 2020 that certain decommissioning deadlines announced by the licensee were pushed back significantly. The authorities will rule on the CEA’s justifications for these schedule push-backs on reception of the facilities’ decommissioning files. 350 ASN Report on the state of nuclear safety and radiation protection in France in 2020 13 – DECOMMISSIONING OF BASIC NUCLEAR INSTALLATIONS