Fuel removal completed at Wylfa

Thursday, 19 September 2019

Magnox reactors are graphite-moderated, gas-cooled and use all-metal, slightly enriched uranium fuel. They can trace their roots back to the earliest days of nuclear technology: the world's first commercial nuclear power station, Calder Hall, was a Magnox reactor. The design takes its name from the magnesium alloy cladding used on the uranium fuel. The UK built a fleet of 26 Magnox reactors.

Wylfa is the biggest and last Magnox site to be built in the UK. Its twin 490 MWe reactors began commercial operation in November 1971 and January 1972, respectively. Unit 2 was permanently shut in April 2012, with unit 1 following in December 2015. Since the end of generation, the site's main focus has been to empty both reactors and send all the remaining used fuel to Sellafield for reprocessing.

The NDA announced today that the final flask of fuel had been removed from the site and sent by rail to Sellafield. A total of 87,890 fuel elements - each measuring 43 inches (1.1 metres) in length - have been removed from the Wylfa reactors since the plant ended generation.

Wylfa Site Director Stuart Law said, "It has not been an easy task and the work at Wylfa is far from complete, but today is a significant landmark in the journey towards care and maintenance.

"The defuelling process was hampered by ageing equipment for the first 18 months which brought challenges, but the dedication and problem-solving abilities of the Wylfa team and expertise drawn from across the nuclear industry led to what is, overall, an incredible performance in completing the task."

Removal of all the fuel from a site is one of the main pieces of hazard reduction work and accounts for over 99% of the radioactivity, the NDA noted. It added that the completion of Wylfa's defuelling programme is "a huge stride" towards the end of all nuclear fuel reprocessing at Sellafield, scheduled for 2020.

"This is a major decommissioning milestone and a clear demonstration that we are making progress in dealing with the UK's civil nuclear legacy," said NDA Chief Executive David Peattie. "The successful completion of the Magnox defuelling programme is testament to the hard work and commitment of the highly skilled workforce across the whole of the NDA group."

Wylfa is the final Magnox plant to complete its defuelling programme, following the completion of that at Calder Hall earlier this month. "Wylfa will now join the rest of the Magnox sites in becoming wholly focused on decommissioning and clean-up," the NDA said.

Magnox Ltd CEO Gwen Parry-Jones said: "As the final Magnox site to defuel, this marks a significant landmark for Magnox Ltd as a whole in carrying out our mission to safely decommission our fleet and marks a new focus on the next phase for the whole company."

Magnox Ltd is the management and operations contractor responsible for 12 nuclear sites and one hydroelectric plant in the UK. Under contract to the site owner, the NDA, the company is responsible for the decommissioning of Berkeley, Bradwell, Chapelcross, Dungeness A, Harwell, Hinkley Point A, Hunterston A, Oldbury, Sizewell A, Trawsfynydd, Winfrith and Wylfa nuclear sites as well as non-nuclear electricity generation at Maentwrog.