Nuclear site runs up 'considerable' costs - report

Sellafield is the UK's largest and most hazardous nuclear site

The Sellafield nuclear site runs up "considerable costs" and is not "value for money", according to the spending watchdog.

The National Audit Office (NAO) also found the Cumbria site could not guarantee all of its hazardous material would be treated before its facilities reached the end of their useful lives.

Progress had been made on "numerous fronts", including the most hazardous waste being removed for the first time, a report added.

Sellafield owner, the Nuclear Decommissioning Authority (NDA), said "there is still more to be done".

Sellafield is the UK's most complex and challenging nuclear site with highly hazardous materials stored there from across the UK.

In recent years, doubts have been raised about its security and physical integrity.

Ongoing concerns over project management, the pace of delivery and staffing mean it is "not yet achieving value for money", the NAO said.

Staff bonuses

Sellafield spent £1.9bn more than it earned in 2023-24.

Four projects that were under way when the NAO last reported in 2018 were "significantly over budget and behind schedule".

Furthermore, in 2023, Sellafield paid out £2.1m more in staff bonuses "than it should have done" - about £200 per person.

Its senior management treated one missed target "as if it had been met", and omitted another missed target from its assessment of how well the organisation had performed, "so the bonus payable was not reduced", the NAO said.

Sellafield spent £1.9bn more than it earned in the latest financial year, according to the report

The report also found Sellafield could not guarantee all of its hazardous waste would be treated, before the plant came to the end of its working life.

Sellafield has to empty waste from ageing facilities, which pose an "intolerable" risk, and store it in buildings which meet modern standards.

For example, the Magnox Swarf Storage Silo (MSSS) - the site's most "hazardous building" - was leaking 2,100 litres of contaminated water each day, the NAO said.

Sellafield and its regulators believe that current leakage rates pose a low risk to workers and the public, it added.

The NAO said Sellafield's good performance against short-term targets was not consistent with its longer-term [decommissioning] milestones.

Labour MP for Whitehaven and Workington, Josh MacAlister, said decision making needed to quicker.

"It is staggering that Sellafield need to go through eight approvals, taking seven months for a decision around major projects," he added.

The NAO acknowledged that the NDA has reorganised itself to address "significant contractual, delivery and procurement problems".

Group CEO David Peattie said: "We remain committed to driving forward improved performance and continuing to deliver our nationally important mission safely, securely, and sustainably."