Operators at the UK’s Sellafield site have removed the first zeolite skip from the First Generation Magnox Storage Pond (FGMSP) to a self-shielded box, which was then placed in the new Interim Storage Facility.
Zeolites were placed into the FGMSP in the 1970s and 80s to help absorb radiation and make the facility safer for personnel. Now they need to be removed as part of the pond clean-up programme. There are another 236 such skips to be removed accounting for a quarter of the total in the pond.
The FGMSP was constructed in the 1950s to store, cool and prepare used Magnox nuclear fuel for recycling into new fuel. During its 26-year operating lifetime it processed approximately 27,000 tonnes of fuel – almost 2.5m fuel rods. Used nuclear fuel from the UK's nine Magnox stations, along with Magnox fuel from both Italy and Japan was held in the FGMSP.
Currently the pond holds some 14,000 cubic metres of contaminated water, in which is stored Magnox used nuclear fuel, radioactive sludge, miscellaneous nuclear wastes and skips. The plan is to progressively retrieve and treat the radiological inventory, reducing the risk posed by its storage and the inherent hazard posed by the materials. The FGMSP has been prioritised for clean-up by the Nuclear Decommissioning Authority (NDA).
Carl Carruthers, head of legacy ponds for Sellafield Ltd, said this was a fantastic achievement and a real step forward. “Removing zeolite skips from the pond and transferring them to safer storage reduces risk and hazard on the site.It also frees up space in the pond which makes our sludge removal and clean-up work easier.”
The 29-tonne self-shielded boxes are built in the UK by Goodwin International via a contract with Westinghouse. Once waste is placed inside it is checked regularly using remote cameras in the box lid. Eventually, the Zeolites will be removed from the boxes and encapsulated, ready for the consignment to the UK’s Geological Disposal Facility.
Roddy Miller, nuclear operations director for Sellafield Ltd, said: “This has been a huge effort involving many different teams at Sellafield. It’s another iconic moment in our decommissioning journey and follows the start of waste retrievals from our two legacy silos.”
David Redpath, NDA group performance assurance director, added: "This accomplishment is not only a first for Sellafield, but a world's first for the nuclear industry. It is a true testament to the hard work and commitment of all those involved. The implementation of this new capability is a key step in reducing the hazard posed by the legacy ponds and demonstrates the strong collaboration between Sellafield and its supply chain."
Image: The self-shielded boxes stored in the new Interim Storage Facility at Sellafield
