Sellafield: MPs warn of ‘sub-optimal’ culture at UK’s most hazardous nuclear site

MPs have warned of a “sub-optimal” culture at the UK’s most hazardous waste site following whistleblower allegations.
Sellafield in Cumbria is managed by the Nuclear Decomissioning Authority (NDA) and is responsible for around 85 per cent of the UK’s nuclear waste.
It has faced criticism for presiding over safety issues, cost overruns and whistleblower allegations of a “toxic culture” of bullying and harrassment, first reported in the Guardian.
The Public Accounts Committee (PAC) said it remained unconvinced that the culture at Sellafield was adequate after its report revealed the NDA paid out £377,200 to settle employment-related claims in 2023-24.
It also found Sellafield Ltd had signed 16 non-disclosure agreements in the last three years. The MPs are now pushing the NDA to publish information around the prevalence and perception of bullying and harassment which were disclosed in its annual report.
“The exceptionally hazardous nature of many of Sellafield’s activities means that it is imperative that all employees and contractors on the site feel able to raise any concerns that they have without fear of consequences,” the committee wrote.
A spokesperson for the NDA said: “We’re committed to an open and respectful culture and we’ve taken decisive action to enable this including strengthening our whistleblowing approach by introducing a group-wide Speak Up policy.
“Evidence shows the improvements are working and the report acknowledges the improvement in staff survey results over recent years, but we are never complacent and will continue to strive to ensure the NDA group is a place where everyone feels respected and empowered to raise issues, knowing that they will be acted upon appropriately.”
In a wide-ranging report, MPs also found that the risks posed by ageing infrastructure at the nuclear site were “intolerable.”
One building – known as Magnox Swarf Storage Silo (MSSS) and deemed the most hazardous in the country – has been slowly leaking contaminated water into the ground since 2018. This does not pose a risk to the public.
The PAC’s report found Sellafield has missed its most important hazard reduction targets more often than it has achieved them and “often by considerable margins”.
While there are some recent signs of improvement, costs and delays are still a huge issue for the project.
Four of its largest projects collectively costing £1.2bn more than first forecast and delivered “many years late”, according to the PAC.
“The intolerable risks presented by Sellafield’s ageing infrastructure are truly world-class,” Sir Geoffrey Clifton-Brown MP, chair of the committee, said.
Sellafield risks ‘simply not good enough’
“Given the tens of billions at stake, and the dangers onsite to both the environment and human life, this is simply not good enough.”
Sellafield’s decommissioning is an exceptional undertaking and will continue at least into the next century.
“As with the fight against climate change, the sheer scale of the hundred-year timeframe of the decommissioning project makes it hard to grasp the immediacy of safety hazards and cost overruns that delays can have,” Clifton-Brown said.
He added: “Every day at Sellafield is a race against time to complete works before buildings reach the end of their life. Our report contains too many signs that this is a race that Sellafield risks losing.”
NDA Group chief executive David Peattie said: “We welcome the scrutiny of the committee and their report; we will now look in more detail at the recommendations and consider how best to address them. We take the findings seriously and the safety of the site and the wellbeing of our people will always be our highest priorities.
“As the committee has noted, Sellafield is the most complex and challenging nuclear site in the UK. We are pleased they recognise improvements in delivering major projects and that we are safely retrieving waste from all four highest hazard facilities.
“With the support of our employees, their representatives, community, and stakeholders we remain committed to driving forward improved performance and continuing to deliver our nationally important mission safely, securely, and sustainably.”