The discovery of a highly radioactive nuclear fuel element at Hunterston in North Ayrshire has sparked concerns about an “alarming safety lapse”.
The site’s local stakeholder group says this is “something that should not have happened” and is demanding answers from nuclear safety regulators. Campaigners claim it’s a “dangerous situation”.
The Scottish Government environmental watchdog says there’s no risk to public health or the environment but that it’s “a legacy matter which needs to be addressed”. The site’s UK Government safety regulator, describes the find as “not unexpected”.
The UK Government company that runs the site promises the fuel element is “in a safe and controlled environment”. Its discovery was “completely expected” and more old fuel may be found, it says.
A fuel element is a long, thin metallic tube containing pellets of uranium. When burnt — or irradiated – in a reactor, it produces dozens of different radioactive materials, including plutonium, and becomes intensely radioactive.
Fuel elements burnt in the now defunct Hunterson A nuclear power station should have been sent to the Sellafield nuclear complex in Cumbria. There, they would have been processed and separated into low-level, medium-level and high-level radioactive waste, as well as plutonium.
But on 3 March 2021 workers emptying an old storage vault at Hunterston discovered an entire 64-centimetre fuel element amongst other radioactive waste. The find was reported to the UK Office for Nuclear Regulation, the Scottish Environment Protection Agency, and the local site stakeholder group.
Hunterston A was a first generation Magnox nuclear station with two reactors that operated from 1964 to 1990 and is currently being decommissioned. It is on the Firth of Clyde adjacent to the Hunterston B nuclear station, whose two reactors are due to close down by January 2022 after the discovery of hundreds of cracks in their graphite cores.
The Hunterston site stakeholders group, which represents local community interests, said it had been informed of the find on 8 March. The fuel element was discovered in the last of five old vaults being emptied of medium-level radioactive waste, it said.
“For a complete fuel rod to have found its way there, instead of into the cooling pond and on to Sellafield, is something, that should not have happened,” said a joint statement from the group’s chair, Rita Holmes, and vice-chair, Stuart McGhie.
“We have contacted the Office of Nuclear Regulation and asked several questions. They have assured us that they will be in touch by the 13 April. Till then, one can only speculate.”
The statement suggested that work practices 40 years ago allowed the fuel element to be left at Hunterston. “Dummy fuel rods have already been found in the vault,” added Holmes and McGhie.
“One would hope that decades ago when this took place, the spent fuel rod was not mistakenly identified as a dummy or that workers then were not unnecessarily exposed.”
They said that the fuel element was “safely isolated in an emptied vault” and that they had “every confidence” that regulators and operators “will now formulate the safest method of dealing with it and any others that are still there.”
The 50-strong group of UK nuclear-free authorities called for a full investigation. “This incident appears to be an alarming safety lapse that has not been resolved in the way it should have been,” said the group Scottish convenor, Glasgow SNP councillor, Feargal Dalton.
“Highly radioactive spent fuel, containing the likes of plutonium, should not be dumped in a vault at Hunterston A, but rather be sent to Sellafield where the appropriate waste management processes are in place.”
Dalton pointed out that The Ferret reported in 2020 that radioactive waste had been detected in a supposed empty fuel flask sent from Sellafield to the Hunterston B plant. “The Office for Nuclear Regulation needs to fully investigate this concerning safety breach,” he added.
The Edinburgh based nuclear consultant and critic, Pete Roche, said: “This dangerous situation illustrates that, when it comes to dealing with nuclear waste, human error is always going to be a potential problem.
“Thank goodness successive Scottish governments have decided to eschew building new reactors and make the most of our plentiful renewable resources instead. Dealing with our legacy nuclear waste is going to be difficult enough without creating yet more as the Westminster government is doing.”
The Scottish Environment Protection Agency (Sepa) confirmed that it had been informed of the find by Magnox, the UK Government company that is decommissioning Hunterston A. “While we are satisfied there is no risk to public health or the environment, this is a legacy matter which needs to be addressed,” said a spokesperson for the agency.
“We are awaiting further details from Magnox on the characterisation of the element before considering the most appropriate next steps. We will work with other regulatory bodies as appropriate.”
Sepa was not able to say how radioactive the fuel element was. But its spokesperson added: “It is clear that this needs to be managed differently from the other items. The element has been isolated from other bunker material and is in secure storage.”
According to the UK Office for Nuclear Regulation (ONR), the fuel element was likely to date back many years and was classed as “higher activity waste”. ONR had also been notified of the find by Magnox.
“The discovery of a spent fuel element in the solid active waste bunker was not unexpected,” said an ONR spokesperson. “There is no risk from this element to workers or the public.”
The spokesperson added: “As decommissioning of Hunterston A continues, Magnox has been making safe progress in removing waste from the five bunkers and this material was discovered while removing waste from the final bunker to be emptied.
“It was always anticipated that fuel fragments or fuel elements may be discovered, and any waste will be safely removed and placed in the radioactive waste store on the site.”
Magnox stressed that such discoveries “formed part of the approved safety case” for decommissioning. “The discovery of fuel, which would have been deposited into the remote waste processing facility when Hunterston A site was operational, is completely expected,” said a company spokesperson.
“The fuel element remains in a safe and controlled environment for processing. We anticipate there will be further occasions when used fuel will be discovered as we continue to retrieve waste safely and securely, and remain alert to this possibility during all our activities.
“Magnox remains sensitive to the local environments in which it operates and is committed to decommissioning its sites with the highest regard to safety and the environment. Regular monitoring is undertaken by our regulators and the information is published on-line.”
This story was updated at 13.55 on 22 March 2021 to include information from Magnox that the fuel element that was found was 64 centimetres long. Cover image ©Thomas Nugent licensed for reuse under this Creative Commons Licence.