The number of safety incidents that could have leaked radiation at the Trident nuclear base on the Clyde has risen to the highest in 15 years, according to information released by the Ministry of Defence (MoD).
One incident in 2023 at the Faslane base, near Helensburgh, was given the MoD’s worst risk rating. This is the first time this has happened since 2008.
Another four incidents at the base in 2023, and one in 2024, were given the second worst rating. The number in 2023 was the highest since 2006.
According to the MoD’s definitions, all six incidents had “actual or potential for radioactive release to the environment”. In total the MoD logged 179 nuclear safety incidents on the Clyde in 2023 and 2024, though most of them were deemed to be less serious.
The MoD insisted that there had been no “radiological impact” or harm to health from any of the incidents. But it declined to provide any further details for national security reasons.
Campaigners described the rise in serious safety incidents as “alarming” and “chilling”. They condemned the secrecy surrounding the incidents, and called for the MoD to give a “full account” of what happened.
The MoD has released new figures to MPs summarising the number of “nuclear site events” in 2023 and 2024 at Faslane and the nearby nuclear bomb store at Coulport.
A total of 158 incidents of all kinds were recorded for 2023, plus 21 so far in 2024. All but six of the incidents were in three less serious categories, suggesting they posed lower risks.
According to the MoD, the incidents included “equipment failures, human error, procedural failings, documentation shortcoming or near-misses”. But it gave no further descriptions of any of the six more serious incidents.
Nuclear Site Events at Faslane and Coulport
| Year | Category A | Category B | Category C | Category D | Below Scale | Total |
|---|---|---|---|---|---|---|
| 2019 | 0 | 1 | 6 | 50 | 101 | 158 |
| 2020 | 0 | 0 | 1 | 26 | 122 | 149 |
| 2021 | 0 | 3 | 10 | 41 | 99 | 153 |
| 2022 | 0 | 2 | 27 | 88 | 87 | 204 |
| 2023 | 1 | 4 | 16 | 54 | 83 | 158 |
| 2024 (Jan-April) | 0 | 1 | 7 | 11 | 2 | 21 |
One incident at Faslane in 2023 was rated as “category A”, the highest risk rating used by the MoD. It has defined such incidents as having an “actual or high potential for radioactive release to the environment” in breach of safety limits.
The last category A incident reported by the MoD was in 2008 when radioactive waste leaked from a barge at Faslane into the Clyde. There were also spillages from nuclear submarines at the base in 2007 and 2006.
The MoD’s figures disclosed four “category B” incidents at Faslane in 2023. This is the highest number of such incidents at the site since 2006, when there were five.
There was another category B incident at Faslane in the first four months of 2024, as well as two in 2022 and three in 2021. The MoD has defined such incidents as having an “actual or high potential for a contained release”, or an “actual or potential for radioactive release to the environment” below safety limits.
Nuclear weapons infrastructure ‘dangerously rotting’
The latest figures were released in response to a parliamentary question by the SNP MP for Edinburgh North and Leith, Deidre Brock. In previous questions, she has obtained information on nuclear safety events at Faslane and Coulport back to 2006.
“My annual questions to UK ministers have exposed steadily declining nuclear safety standards at Faslane and Coulport, but the increase in the severity of incidents last year is particularly alarming,” she told The Ferret.
“Reports detailing these incidents should be made public again so that people of Scotland – including those who live near the bases – can weigh up for themselves the risks created by the storage of these nuclear warheads.”
She accused the MoD of “playing down” the safety breaches, pointing out that in December 2023 the former Prime Minister Boris Johnson’s senior advisor, Dominic Cummins, described the UK’s nuclear weapons infrastructure as “dangerously rotting”.
Brock said she would be submitting further parliamentary questions asking for details of the more serious incidents in 2023 and 2024. “But it shouldn’t take the digging of individual MPs or journalists to get piecemeal bits of information from the MoD,” she argued.
The Scottish Campaign for Nuclear Disarmament branded the category A incident at Faslane as “chilling”. The UK’s nuclear weapons were a “catastrophe in waiting”, said the campaign chair, Lynn Jamieson.
She accused the UK government of wanting to suppress “bad news” about nuclear weapons.
The Nuclear Information Service, which researches and criticises nuclear weapons, called for the MoD to give a “full account” of what happened. “This is very concerning, and shows there are clearly problems with safety standards at Faslane,” said the service’s director, David Cullen.
He pointed out that there had been another “serious workplace safety failure” on a Trident submarine at Faslane in August 2021. The UK Office for Nuclear Regulation issued an improvement notice after an “electrical overload”.
“This suggests that safety is just not being taken as seriously as it should be,” Cullen added.
‘No harm’ from nuclear events
An MoD spokesperson said: “We have robust safety measures in place at all Ministry of Defence nuclear sites and we take safety incidents very seriously. Our nuclear programmes are subject to regular independent scrutiny and reviews.”
According to the MoD, the release of information on nuclear safety had to strike a balance between public interest and national safety and security.
“None of the events caused harm to the health of any member of staff on the naval base or to any member of the public or have resulted in any radiological impact to the environment,” said the defence minister, James Cartlidge.
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Cover image thanks to Ministry of Defence
