The Office for Nuclear Regulation (ONR) has overseen a major milestone in the completion of defuelling at Hunterston B Nuclear Power Station.
After nearly 46 years of generating electricity, the site has now been declared nuclear fuel free.
Defuelling is the process of safely removing the nuclear fuel from the two reactors, which removes the vast majority of the radioactive hazard from the site.
The EDF-run site in North Ayrshire, Scotland, has now completed the defuelling of Reactor 4, with Reactor 3 being declared fuel free in 2023.
Hunterston B is the first of the UK’s seven advanced gas-cooled reactor (AGR) stations to be declared fuel free.
Since 2022, nuclear fuel has been removed from both reactors and safely transported by rail by Nuclear Transport Solutions to Sellafield in Cumbria for storage.
Mike Webb, ONR’s Head of Operating Reactors Sub-Division, said: “With our enabling regulatory approach, our inspectors have worked very closely with EDF throughout the defuelling phase to support them to safely reach this significant milestone.”
Now the site’s focus turns to transferring the site licence from EDF to the Nuclear Decommissioning Authority (NDA) for its subsidiary Nuclear Restoration Services (NRS) to carry out decommissioning work.
ONR has already received an application from NRS seeking regulatory approval to become the new dutyholder for Hunterston B.
This recent licence application to ONR schedules the point of transfer from EDF to NRS at spring 2026.
NRS will decommission the site, which will involve dismantling and demolishing the plant and buildings.
Currently, NRS is responsible for safely decommissioning 13 sites across the country, including the first generation of nuclear and research sites.
At the point of fuel free verification, the regulation of Hunterston B moved from ONR's Operating Facilities directorate to its Sellafield decommissioning, fuel and waste directorate.
Tom Eagleton, ONR’s Head of Safety Regulation for Decommissioning fuel and waste sub-directorate, said: “We will continue to effectively and efficiently regulate the site throughout the decommissioning phase to ensure the licensee complies with all regulations to safeguard workers and the public.”