Select committee: Public Accounts Committee
Conclusion 28
28th Report - Decommissioning Sellafield
Published 4 Jun 2025
Addressed to HM Treasury
Public Accounts Committee Decommissioning Sellafield All items in this report Report on parliament.uk ↗ Inquiry on parliament.uk ↗
Conclusion (the committee's words)
The NDA also needs to construct a ‘Geological Disposal Facility’ (‘GDF’) to store waste permanently – including that currently at Sellafield. This project is still at a very early stage: it needs to drill boreholes before it can even start developing a ‘Preliminary Design’ and also needs to conduct a ‘Test of Public Support’ with the local community .80 It has been considering sites in Cumbria and Lincolnshire – though we understand that Lincolnshire County Council has recently announced it is likely to withdraw, citing “the uncertainty and slow pace of this process”.81 Even though the project is still at an early stage, the opening date has slipped considerably, with the NDA now expecting the GDF to open in “the late 2050s”.82 The previous Committee was told in 2015 that the GDF was expected to open in 2040.83 Delays to the GDF have serious consequences for value for money at 76 Qq 94–97 77 Qq 98–103 78 Committee of Public Accounts, Nuclear Decommissioning Authority: risk reduction at Sellafield, Sixty–Fifth Report of Session 2017 –2019, HC 1375, 31 October 2018 79 Qq 80–81 80 Letter from the Group Chief Executive Officer at the Nuclear Decommissioning Authority relating to the oral evidence session held on 20 March on Decommissioning Sellafield, 4 April 2025, page 11 81 Q112; Lincolnshire County Council, County council set to withdraw from nuclear waste facility group, 18 March 2025 82 Q 104 83 Committee of Public Accounts, Oral Evidence: Sellafield recall, HC 1096, 11 March 2015, Q105 20 Sellafield as extra buildings could have to be constructed for short–term storage of the waste: a delay of a decade could cost Sellafield Ltd £500 million–£760 million.84 Creating the right culture in the NDA group
From: Public Accounts Committee, 28th Report - Decommissioning Sellafield (HC 363), 4 June 2025
Government response
Latest Treasury Minutes progress report to the Committee of Public Accounts on the Twenty-eighth Report of Session 2024-26
The government responded to the whole report on 4 June 2026 (deadline 4 August 2025).
Treasury minutes: Government response to the Committee of Public Accounts on the Twenty-eighth report from Session 2024-26
Published 18 September 2025.
Summary written by Accountability Index from the government's response. It is not the government's own words.The government says it agrees with each of the Committee's recommendations covered in this extract, with target implementation dates ranging from December 2025 to March 2027, though some are already implemented and some publication details remain to be settled.
- On oversight (recommendation 1), the government agrees and describes the recommendation as implemented. Since January 2025 the department's Principal Sponsor chairs monthly performance meetings, and a review of the revised governance structure will be initiated within 2025-26.
- On medium-term targets (recommendation 2), the government agrees, with a target date of March 2027. Work "is required to establish how and then when this information would be made public", and DESNZ will commission an independent, externally led review of the NDA Group by end-2025.
- On asset management (recommendation 4), the government agrees and says the recommendation is implemented. It states that "Solely increasing the productivity of maintenance teams misses the demands" of the site's complex asset picture.
- On long-term cost scenarios (recommendation 5), the government agrees, with a target date of December 2026. It says "It will be necessary to agree the mechanism and timing, including what is published".