Spain’s Council of Ministers on 27 July authorised decommissioning and waste management firm Enresa to launch a tender for a contract for the design, support with licensing, manufacture and supply of a used nuclear fuel storage system for use at the Almaraz, Ascó, Cofrentes and Vandellós II NPPs. The contract has a maximum limit of €220.08 million ($260 million) including VAT.
At present, all NPPs, with the exception of Vandellós II, have onsite independent interim storage facilities (ATIs). In addition to the existing facilities, it is necessary to provide new temporary storage capacities, which will be operational in 2026, for all the NPPs in operation, except Trillo. The new ATIs will be based on welded metal capsules and concrete envelopes, Enresa noted.
The contract is for a single system that allows the dry storage of used fuel generated in the Ascó, Cofrentes and Vandellós II plants from 2026. At the Almaraz plant the new system will enable the used fuel pools to be emptied after the shutdown of its two units, scheduled in 2027 and 2028, in order to start its dismantling.
The new storage systems will have the same design for all the plants and will be subject to a single licensing process, and should achieve savings due to economies of scale and the shared use of auxiliary equipment and spare parts, common procedures and training.
The new ATIs will be compatible with any of the temporary storage strategies adopted in the new General Radioactive Waste Plan (GRWP), which is currently being processed. When the time comes, the welded capsules will be moved to a centralised warehouse.
Implementation will take five years from the start of the tender until the facilities are operational in 2026, according to the schedule provided in the tender.
The GRWP sets out the strategies and activities required for radioactive waste management, decommissioning, and the economic and financial analysis of these activities. It is approved by the Council of Ministers and regularly updated.
The Trillo NPP has used a cask storage system to house used fuel since 2002 on a temporary basis. The installation has concrete walls and roof, and can accommodate up to 80 dual-purpose casks (for storage and transportation). An interim storage facility has already been constructed at the José Cabrera plant and is designed for the dry storage of all used fuel unloaded from the reactor, which shut down in 2006. It comprises 12 modules loaded with used fuel and four extra additional casks containing the most highly radioactive metal pieces from the segmentation of the reactor internals. The Ascó plant also has an interim storage facility for the dry storage of used fuel unloaded from its two reactors. It comprises two slabs of reinforced concrete, each with capacity for 16 storage modules.
As to centralised storage, Villar de Cañas in central Cuenca province was selected as the location for the Centralised Storage (CTS) in December 2011. In July 2015, the Nuclear Safety Council approved it as suitable site for a national high-level waste storage facility. The CTS has been designed for a 100-year operational life, although the current GRWP specifies 60 years.