Universal Registration Document 2022

At 31 December 2022, the gross amounts estimated under year-end economic conditions (amounts still to be spent) and the present value of those amounts are as follows, presented by type of reactor technology:

Provisions for decommissioning of permanently shut-down nuclear plants also cover dismantling costs for related facilities such as the APEC Fuel Storage Workshop at Creys-Malville and the BCOT Operational Hot Unit at Tricastin.

Compared to decommissioning costs for the PWR technology, the cost at completion (all costs both settled and remaining) for decommissioning of the other reactors is higher, to different extents depending on their specific characteristics:

• costs are around twice as high for Brennilis (completion cost of approximately €0.96 billion for one reactor) due to its compactness, the fact that the core is encased in concrete and thus difficult to access, the absence of a fuel pool, which complicates remote-controlled segmentation, and the presence of zircaloy (a fire hazard), meaning that segmentation work takes longer and must be more closely supervised;
• costs are around twice as high for UNGG reactors (completion cost of approximately €7 billion for six reactors), because they require removal of 20 times more material than a PWR due to their size, and contain graphite which is hard to access and requires special handling such that specific remote-controlled equipment must be developed;
• costs are around four times as high for Superphenix (completion cost of approximately €1.9 billion for one reactor), due to processing of sodium for which elimination is very sensitive, and the size of the facilities, especially the reactor (with a vessel 20 times bigger than the vessel of the 1300MW PWR).

The following progress has been made on permanently shut-down plants:

• Chooz A: the reactor was shut down in 1991 and nuclear dismantling began in 2007 after the dismantling decree was issued. The final stage of dismantling began in 2016 and involves segmentation, conditioning and removal of reactor vessel internals, followed by dismantling of the vessel itself. These operations should be completed by December 2025. Under the new full continuous decommissioning scenario adopted in 2021, this plant is expected to be declassified by late 2035;
• Fessenheim: the two pressurised water reactors were shut down definitively on 22 February 2020 and 30 June 2020 respectively, in accordance with the law and before the end of their technical operating lifetime. The dismantling plan was sent to the ASN in September 2019 together with the declaration of the permanent shutdown of this INB. The studies conducted in 2019 and 2020 focused on preparing the dismantling plan, which was sent to the ASN on 2 December 2020. In early 2022, the Mission de la Sûreté Nucléaire et de la Radioprotection (MSNR) and the ASN formally acknowledged reception of an expanded version of this plan. The dismantling decree for the Fessenheim installations is now expected to be issued in early 2026, and its issuance will mark the start of the dismantling phase. At the end of 2022, the pre-dismantling operations (full defueling of reactors 1 and 2, treatment and removal of boron as planned, total chemical decontamination of the primary circuit of reactor 1 and connected circuits, etc) were in line with the provisional schedule. Total decontamination of reactor 2 was deferred to early 2023, without affecting the critical path;
• UNGG reactors: these six reactors were shut down between 1973 and 1994 and received their dismantling decrees between 2008 and 2010 (except for Chinon A1 and A2). Defuelling and circuit draining have been completed for all these reactors, and dismantling operations are in process for the conventional and nuclear buildings in the periphery of the “reactor caissons”. Following the ASN’s decision of 2020, applications for dismantling permits were submitted for all these reactors in December 2022, to obtain new decrees allowing continuation of dismantling operations under an “in-air” strategy (these are expected for the end of 2026 at the earliest). Opening of the top part of the first UNGG reactor caisson –  Chinon A2 – is expected in 2034: the initial extractions of vessel internals and graphite blocks are due to start in 2041 and last 14 years. In parallel, the other UNGG sites are finalising work to put the sites into a safe storage configuration (by 2037). A safe storage configuration state means that 80% of surfaces have been dismantled and the reactor caissons are safe while awaiting the full benefit experience on dismantling the caisson of the Chinon A2 first-of-a-kind unit. Opening of subsequent caissons is scheduled to begin from 2056;
• Superphenix: this plant was shut down in 1998 and received its dismantling decree in 2006. The following key stages have been completed: defuelling, dismantling of the turbine hall, drainage of the circuits, processing and elimination of the sodium used for cooling in all circuits, filling the reactor vessel, opening and extracting the vessel caps, and the start of dismantling of the core vessel cap (which weighs several hundred tonnes). The next stages are dismantling the vessel internals (due to be completed in 2026), electromechanical dismantling in the reactor building, then decontamination (the plant is expected to be declassified in 2034);
• Brennilis: this plant was shut down in 1985 and received a partial dismantling decree in 2011 allowing dismantling of all installations peripheral to the “reactor block”. The following key stages have been completed: defuelling, dismantling of the machine room, the fuel building, auxiliary buildings, heat exchangers and the effluent treatment station. The next stages are examination of the application for full dismantling authorisation, with a view to obtaining a dismantling decree in 2023 that would enable EDF to dismantle the reactor block (the end of these operations is currently forecast at 2040). Following a public inquiry held from 15 November 2021 to 2 February 2022, the inquiry commissioner issued an unreservedly favourable opinion on 2 March 2022.

15.1.1.4 Provisions for last cores

These provisions cover the future expenses resulting from scrapping fuel that will only be partially irradiated when the reactor is shut down. They are estimated based on:

• the cost of the loss on fuel in the reactor that is not totally spent at the time of final reactor shutdown and cannot be reused due to technical and regulatory constraints (“front-end” expenses);
• the cost of fuel processing, and waste removal and storage operations (“back-end” expenses). These costs are estimated in a similar way to provisions for spent fuel management and long-term radioactive waste management.

These unavoidable costs are components of the cost of nuclear reactor shutdown and decommissioning. As such, they are fully covered by provisions from the commissioning date and an asset associated with the provision is recognised. In a decision of 11 December 2020, France’s Council of State challenged the tax-deductibility of the consequences of immediate recognition of a provision for dismantling of the last core (“front-end” last core expenses) (see note 17.3.1).