Navy made legal threats to try and keep nuclear pollution secret

The Royal Navy threatened legal action as part of a fierce, high-level, behind-the-scenes battle to block publication of information about radioactive pollution at the Coulport nuclear bomb base on the Clyde.

Files released to The Ferret reveal that over nine days in July and August the navy sent 130 emails, held five meetings and made numerous phone calls urging the Scottish Environment Protection Agency (Sepa) to keep details of the pollution secret.

Naval officials repeatedly warned of legal action, spoke of the need to “calm some nerves” and said they were “deeply uncomfortable” with information proposed for release. One was anxious to avoid “another crazy Friday”, while another complained of becoming a “zombie” after a long week.

Top naval commanders also had an online meeting with the Scottish Information Commissioner, David Hamilton, late one evening to try and persuade him to reverse his decision to reject most of their pleas for secrecy.

But all these eleventh-hour efforts failed. As The Ferret reported on 9 August, Sepa released 33 files revealing that Coulport had polluted Loch Long on the Clyde with radioactive waste after old water pipes burst and caused a flood in 2019.

Campaigners accused the navy of “harassing” Sepa, and praised Hamilton for refusing to be “intimidated”. Politicians demanded less secrecy from the Ministry of Defence (MoD).

The MoD said it had to “balance” the public’s right to know with releasing information which would compromise national security. Sepa insisted it was firmly committed to transparency.

Loch polluted by radioactive waste from nuclear bomb plant

Loch Long on the Clyde has been contaminated by radioactive waste from the UK’s nuclear bomb store where old water pipes have repeatedly burst and caused floods, files released after a six-year secrecy battle reveal. Internal documents obtained by The Ferret from the Scottish Government’s environmental watchdog disclose

The FerretRob Edwards

Naval commanders ‘getting concerned’

The Ferret first made a freedom of information request for files on radioactive problems at Coulport and Faslane in 2019, and then again in 2023 and 2024. But despite multiple reviews, most files were kept secret for national security reasons, after Sepa consulted the MoD.

The secrecy was overturned, however, after we appealed to Hamilton. In June 2025 he ordered Sepa to release most of the files by 28 July, saying they threatened “reputations” not national security.

But the release was delayed to 4 August after the MoD pleaded for more time to assess “additional national security considerations”. Sepa eventually released the 33 files to The Ferret late on 5 August.

Now emails released by Sepa and Hamilton in response to further freedom of information requests from The Ferret have disclosed what was happening behind the scenes. 

On working days between 24 July and 5 August the Royal Navy sent an average of more than 14 emails a day to Sepa, to try and limit the amount of information released. Naval officials also frequently phoned and met with Sepa. 

On 30 July the MoD proposed a series of redactions to the documents that were scheduled to be released. They “represent the minimal changes which are required in order to protect national security,” it argued.

The MoD tried to add to their shameful history of nuclear cover-ups by harassing officials with false claims of national security, hoping we’d never know radioactivity was negligently leaked from Coulport.

Early on 31 July a naval official asked Sepa to forward the MoD’s proposed redactions to Hamilton, apologising for failing to make that clearer earlier. “It’s been a long week and I resemble a zombie!” the official wrote.

Sepa assured the MoD it had included “all MoD redactions” in a submission to Hamilton.

But then an email from a naval official later on 31 July said the “chain of command are getting concerned” about “timelines” if Hamilton rejected the redactions. The official warned of legal action, adding: “Grateful for your advice to calm some nerves.”

The kind of legal action the navy was considering is unclear, as key text has been redacted. But the only way of challenging Hamilton’s decisions is by appealing to the Court of Session in Edinburgh on a point of law.

Another email on 1 August again warned Sepa that the MoD was “likely to challenge” the release of information that “adversely prejudiced” national security. It asked Sepa to "withhold release of the relevant documents while we follow due process”.

On 4 August Hamilton rejected the majority of the MoD’s proposed redactions. The MoD again told Sepa that it was considering action “to prevent disclosure of the documents”, and asked Sepa not to release them “until this decision has been  made”.

But Sepa responded saying that it was planning to release the information as ordered by Hamilton. It was not “tenable” to further delay the release “from a reputational risk perspective”, Sepa said.

MoD meetings with Hamilton

The MoD also requested an “urgent” meeting with Hamilton and his staff on 25 July to consider MoD “concerns”. Another meeting was requested by the MoD on Thursday 31 July, with one official keen to “prevent another crazy Friday”.

On 1 August the navy’s director of submarines, Rear Admiral Andy Perks, told Hamilton that he had spoken directly to Sepa’s chief executive, Nicole Paterson, to try and find “a pragmatic way forward”. He stressed the need to “maintain national security backstops throughout”.

Perks praised Hamilton’s “continued support and pragmatism”, adding that it had been "greatly appreciated” by the First Sea Lord, General Sir Gwyn Jenkins.

On 4 August, after learning that Hamilton had rejected most of the MoD proposed redactions, Perks emailed again asking for another meeting that evening “to find a pragmatic way forward”.

In reply Hamilton said he was legally not allowed to discuss the case with third parties. “Much of the information that the Royal Navy would like to withhold is already in the public domain,” he said.

“As a courtesy I am happy to speak later tonight but with the understanding that I can't discuss the case in detail.” A meeting took place just after 8pm that evening, after Hamilton had returned from a karate class.

After Sepa released files to The Ferret on 5 August, Hamilton pointed out that a few details had been wrongly redacted. Sepa then had to re-release the files with those redactions removed. 

When this was flagged to the MoD on 8 August, it said it was “deeply uncomfortable”. But it added: “We have objections but we won’t appeal further.”

Aggressive manoeuvres

The Campaign for Freedom of Information in Scotland was pleased that Hamilton “refused to be intimidated” by the MoD’s “aggressive manoeuvres”. The public interest had finally been served by disclosure, said campaign director, Carole Ewart. 

She thought the MoD might have “overlooked” the fact that Scotland’s environmental information law is tougher than that south of the border. Details can only be kept secret in Scotland if they “prejudice substantially” national security, but UK law says they can remain hidden if they just “adversely affect” national security.

The Scottish Campaign for Nuclear Disarmament thanked Hamilton for acting “without fear or favour” in the public interest. “The MoD tried to add to their shameful history of nuclear cover-ups by harassing officials with false claims of national security, hoping we’d never know radioactivity was negligently leaked from Coulport,” said campaign chair, Lynn Jamieson.

The SNP MSP and chair of the cross-party group on nuclear disarmament, Bill Kidd, said that the Scottish Parliament’s net zero and energy committee would be investigating transparency over pollution at Coulport and the neighbouring Faslane nuclear submarine base.

There were “worrying undercurrents of MoD behaviour in relation to secrecy over radioactive pollution” that needed to be investigated, he added.

The former Scottish Green leader, Patrick Harvie MSP, accused the MoD of making a “totally inappropriate intervention” in an attempt “to cover up and distract from what were very serious failures.”

We must balance the public’s right to know with releasing information which would compromise national security into the possession of our adversaries.

The MoD defended its intervention as “legitimate”, pointing out that it was “voluntarily” regulated by Sepa and welcomed the scrutiny. “We must balance the public’s right to know with releasing information which would compromise national security into the possession of our adversaries,” said an MoD spokesperson.

“We explored in a professional way a range of options to ensure we struck the right balance while maintaining the security of the British people which is imperative. The redaction of certain information highlights the importance of consulting us to ensure the protection of national security-sensitive information.”

Sepa stressed that it was “firmly committed” to transparency. “Our approach is always that publication is the default and withholding information is the exception, only when it is necessary, proportionate and legally justified,” said the agency’s chief officer, Kirsty-Louise Campbell.

“This includes careful consideration of national security and public safety - particularly for sites handling radioactive substances, whether military or civilian.”

The Scottish Information Commissioner, David Hamilton, pointed out it was Sepa’s responsibility to make representations to him on The Ferret’s FoI appeal. “In the unusual circumstances of this case, however, and, as a responsible regulator, I also spoke with Royal Navy commanders to ensure I was fully aware of any relevant national security issues,” he said.

“After these discussions, I advised Sepa that I was agreeable to a small number of minor redactions in the interests of national security. I should note that, throughout this process, I felt under no pressure to review my decision or make redactions – all of which were founded in Scotland’s environmental transparency laws.”