Sellafield Limited has announced its “most significant stride ever” with the removal of the last batch of bulk metal fuel from the Pile Fuel Storage Pond (PFSP) in Cumbria, northwest England. The fuel has been moved to safer, more modern storage in the Fuel Handling Plant.
Decommissioning teams lifted the final skip of ‘metal fuel’ from the pond via a remote controlled process. Retrieval of the pond’s ‘canned fuel’ inventory was successfully completed in October 2015. The project was commissioned and delivered under the management of Nuclear Management Partners.
In a joint statement, Sellafield Ltd and the Nuclear Decommissioning Authority said: “The work means radioactivity levels at the 68-year-old pond have been cut by 70%, vastly reducing the risk it poses to people and environment.” They added, “The achievement is the most visible sign yet of progress in the Nuclear Decommissioning Authority’s (NDA’s) program to clean-up the legacy of Britain’s early nuclear industry, which is set to continue for at least another 100 years.” The removed fuel has been transferred to a modern storage building at Sellafield where it can be held in a “far safer environment”, they said.
The final skip of ‘metal fuel’ is removed from the PFSP (Image: Sellafield)
The pond had played a “pivotal role” in the development of the UK’s original nuclear deterrent, the company noted. Used fuel rods were cooled in the pond after they had been burned in the old Windscale Pile reactors to create weapons material at the height of the Cold War in the 1940s and 50s.
The statement added that the pond had also played a vital role during Britain’s worst nuclear accident – the 1957 Windscale fire. Rods pushed through the core of the reactor by workers battling the blaze were later transferred to the pond for storage.
Pete Lutwyche, the NDA’s Sellafield program director said: “This is a huge achievement in the decommissioning of Sellafield’s most hazardous facilities, and I congratulate the team on their commitment, dedication and hard work.”
Paul Foster, managing director of Sellafield Ltd, said: “This is a truly landmark moment in the decommissioning of Sellafield. Removing decades-old corroded fuel from an aging facility and placing into modern containment makes Sellafield, and the whole of the UK, a far safer place.” Foster added that the “enormity of the challenge” could not be overstated, since the pond was “built with no design for how its contents would be removed”.
He said: “We have had to retro-fit an export process and then safely execute it in one of the most challenging environments imaginable. Operators removed the fuel from 40-feet away, working behind radiation shields and using cameras and well-rehearsed procedures. The approach required a step-change in thinking at Sellafield as it necessitated bringing fuel skips up and out of the water and therefore being ‘unshielded’ for a time.”
The Office for Nuclear Regulation welcomed the decommissioning milestone and said that attention will now shift to the remaining solids and sludge in the pond, including any residual fuel which will be exported in due course.
“The key milestone has been achieved through a fit-for-purpose, lead-and-learn approach where the unshielded skips of fuel were lifted out of the pond, transferred across the operational area and then lowered down a hoist well into a shielded flask to be lidded and transported,” the ONR said. “Operators controlled the move from 40-feet away, working behind radiation shielding using cameras and well-rehearsed procedures to complete an operation first trialled in 2011, when 350kg of metal fuel was exported from PFSP.”
Andy Lindley, Sellafield program director, said the removal of bulk metal fuel from PFSP “many years ahead of schedule” was another significant risk reduction step in the wider clean-up of Sellafield’s legacy facilities. “We have worked with Sellafield and other key stakeholders to expedite the project safely and in the coming months our attention will switch to the removal of the remaining wastes from the facility, including sludge,” he said.
Source: World Nuclear News