The Silos Maintenance Facility will house and maintain the machinery that will get the waste out of two of the oldest plants on the site: the Magnox Swarf Storage Silo and the Pile Fuel Cladding Silo. Both contain irradiated waste from nuclear fuel.
The £250 million project has taken nine years to build. Sellafield, Balfour Beatty and Cavendish Nuclear, working together to deliver design, construct, install and test of the facility.
The building is a workshop to maintain powered plant that contains radioactive waste emptied from the Magnox Swarf Storage Silo, over the 25-year programme to remove that waste.
It will also support equipment used to empty the Pile Fuel Cladding Silo, which was originally designed to be permanently sealed.
Sellafield explains that the Pile Fuel Cladding Silo retrieval equipment was lifted into place on top of a modern ‘superstructure’ built on the side of the building in nine large modules. Waste retrieval trials are expected to begin later this year, moving into larger scale waste removal in 2020.
The Pile Fuel Cladding Silo was built in the 1950s when the site’s purpose was to make material for nuclear weapons. In 2016, Sellafield reports that six holes were cut into the side of the silo, the first breaking of the structure since it was built. Six giant steel doors were then installed.
To remove the waste, a crane grabber will reach through a hole, scoop up waste, deposit the waste in a special metal box for storage in another facility currently being built.
The work is being carried out in collaboration with Bechtel Cavendish Nuclear Solutions, a US-UK joint venture appointed to help design, manufacture, test and install the machinery needed to empty the silo. The equipment has been trialled at Rosyth, Scotland at a mock-up model of the silo.