The former cooling ponds at the UK’s Dungeness A nuclear site are being cleaned up by divers who are working under water to dismantle pond skips that were previously used to store used nuclear fuel, according to Magnox Ltd, which manages the site. Magnox, owned by Cavendish Fluor Partnership, is the management and operations contractor responsible for managing the UK's 12 former Magnox NPP sites on behalf of the Nuclear Decommissioning Authority (NDA).
The work involves cutting up the skips and packaging them for disposal, while the water that remains in the ponds provides additional radiation protection. Cutting skips after they have been removed from the ponds would require additional measures to prevent potential airborne contamination, Magnox said. During electricity generation, the ponds were used to store used nuclear fuel in skips before it was sent offsite for reprocessing. The site has been fuel-free for over four years but disposal is needed for the skips, which are classed as intermediate-level waste. The dismantled skips will be stored in waste containers in a shielded storage area onsite before being packaged for interim storage.
Some 20t of pond furniture, including framework and machinery and classed as low-level waste, will also be removed and cut up before being sent for disposal to the UK's Low Level Waste Repository in West Cumbria.
The work in Dungeness A's ponds is expected to be completed in early 2017, and Magnox will pass on its experience to other sites where similar work is required, such as Sizewell A, in Sussex. Dungeness A's two 225MWe Magnox reactors operated from 1965 to 2006 and has been fuel free since June 2012. The defuelling programme saw the removal of 99% of the Kent site's radioactive hazard.