Source · Select Committees · Public Accounts Committee
Recommendation 3
3
Accepted
Require Sellafield Ltd to update Committee on plutonium analysis and alternative project costs.
Conclusion
Sellafield’s ability to deliver its largest projects on time and budget is still too variable. While there are some recent signs of improvement, Sellafield continues to repeat old mistakes. Four of the largest projects at Sellafield will collectively cost £1.15 billion more, and be delivered many years later than Sellafield Ltd expected in 2018, the last time this Committee examined Sellafield. Sellafield has a poor track record of delays and cost overruns, but the NDA reassured us in 2018 that cost forecasting is improving while the Department believed that the estimates of those costs have begun to stabilise. Nevertheless, there are some signs that a corner may finally have been turned. Sellafield Ltd is now working with a group of contractors in a different way, which places more emphasis on planning. As a result, most of the projects that have started more recently are being delivered in line with their business cases. However, one of Sellafield’s more recent major projects, the Replacement Analytical Project (RAP) has been managed very poorly indeed. When Sellafield Ltd ‘paused’ RAP last year, it was expected to cost up to £1 billion more than originally approved while new plutonium analysis capabilities would be at least 5 years late. Sellafield Ltd now believes that it can cut this gap to around one year and save money by converting a different building instead. However, £127 million spent on RAP will have been wasted. 4 recommendation As it carries out more detailed planning for future provision of Analytical Services, Sellafield Ltd should write to the Committee at a suitable point (but within six months) to update us on: • when it expects to be able to carry out the plutonium analysis the site will require (and what level of confidence it has in this estimate); • how much it expects to spend on the projects it has decided to carry out instead of the Replacement Analytical Project; and • what assessment it has made of the costs and value for money of mainta
Government Response Summary
The government agrees, stating Sellafield Ltd will provide an update on future analytical capability plans within six months (December 2025) and a further update once the Outline Business Case for Special Nuclear Material capability is completed (June 2026), including a delivery schedule and confidence level.
Government Response
Accepted
HM Government
Accepted
The government agrees with the recommendation. such as nuclear fuels and waste, and Special Nuclear Material (SNM) such as plutonium. Sellafield Ltd will provide an update on future analytical capability plans as alternatives to the Replacement Analytical Project within six months of the publication of this report (December 2025). A further update will be given once the Outline Business Case to provide the SNM capability has been completed (June 2026) which will include a schedule for delivery (and associated confidence level). The 2024 NAO report noted positive progress had been made in major project delivery at Sellafield, identifying that more recent projects are expected to be completed in line with business case assumptions. It recognised the positive ratings received by key projects from the then Infrastructure Projects Authority, and the gains made in Reference Class Forecasting to improve cost estimates. The nationally recognised project delivery entity, the Programme and Project Partners (PPP) model was noted positively in the report: “Sellafield and the Infrastructure and Projects Authority believe that the PPP model has contributed significantly to strong performance on two of its first three projects, and external reviews have also identified a strong internal culture that is adding value to Sellafield.” A target focused on improving project and contract delivery by sharing and implementing lessons learned was successfully delivered in 2024-25 and will inform the NDA’s group-wide organisational learning policy.