Progress in Sellafield pond clearance
The first 100 tonnes of contaminated equipment that has laid for decades in the Pile Fuel Storage Pond (PFSP) at the Sellafield site in the UK has been retrieved for final disposal.
A piece of redundant equipment is removed from the pond (Image: Sellafield Ltd) |
The pond - built and commissioned between 1948 and 1952 - and the adjoining decanning building provided the storage and cooling facility for irradiated fuel and isotopes from the two Windscale pile reactors. The PFSP processed 2100 tonnes of pile fuel and 300 tonnes of Magnox fuel. The placement of material in the pond - the first nuclear fuel storage pond to be constructed at Sellafield - ceased in the 1970s. Extensive refurbishment and re-equipping took place in the 1980s and decommissioning started in the 1990s.
The subdivided outdoor storage pond is some 100 metres long, 25 metres wide, 7 metres deep and contains over 15 million litres of water, making it the world's largest open-air nuclear storage pond. The PFSP contains skips of irradiated fuel and waste, each skip containing 6-12 cubic metres of material. The removal of sludge - consisting of algae, corrosion products and wind-blown material - that had accumulated in it began in 2008. Fuel removal began in September 2011.
The first 100 tonnes of contaminated redundant equipment has now been removed from the facility. This has included eight of the 30 waste and transport flasks, each weighing 2-3 tonnes, and all of the pile fuel decanners, each weighing over one tonne. Sellafield Ltd has also stripped out and removed redundant metal structures above and below the water line in the pond bays.
PFSP head of projects Derek Carlisle said, "The 100 tonnes of contaminated metal we have removed so far has been cleaned up for disposal in the national low-level waste repository near Drigg."
A further 650 tonnes of contaminated metal remains to be retrieved from the pond.
Researched and written
by World Nuclear News