The Nuclear Decommissioning Authority (NDA) is the government-funded body responsible for managing the decommissioning and clean-up of the UK civil nuclear sites. It is also responsible for implementing government policy on the long-term management of nuclear waste.
NDA manages 17 sites across the UK. Sellafield Ltd is the largest and most complex element of the NDA’s mission, while Magnox Ltd manages the remediation of 10 former reactor sites and 2 former research sites. Within NDA Group, Nuclear Waste Services (NWS), is charged with finding a site for a Geological Disposal Facility (GDF), and managing the Low-Level Waste (LLW) repository. Prior to 2022, these programmes were managed by Radioactive Waste Management Ltd and LLWR Ltd respectively, however they have now been amalgamated into the new single waste division and are wholly owned subsidiaries of NDA.
Nuleaf engages with NDA to represent the local authority perspective on a number of issues including:
- the impacts of NDA’s work on local communities and wider sustainability;
- stakeholder engagement; and
- the implications of decommissioning and waste management proposals, particular in terms of land use and waste planning and proposals for the future use of sites.
Nuleaf sits on a range of NDA fora including the Site Decommissioning and Remediation, Integrated Waste Management and Critical Enablers Theme Overview Groups and the Net Zero Carbon Group. We are a member of the advisory group for the development of NDA Strategy, and also engage directly with Magnox, RWM and LLWR. Our Radioactive Waste Planning Group provides a forum for land use and waste planners to engage on plans for NDA sites.
Nuclear decommissioning
The NDA’s mission is to clean up the UK’s legacy nuclear sites and make them available for next planned use.
By far the largest and most complex decommissioning challenge is presented by Sellafield in West Cumbria. The site employs around 10,000 staff. It has a nuclear legacy going back to the 1940s and encompassing the world’s first commercial nuclear power station. Sellafield’s high hazard legacy ponds and silos are amongst the most complex and difficult decommissioning challenges in the world. The site was also involved in nuclear reprocessing, but these facilities are now closed or due to close in 2021.
A further 10 former nuclear power plants and 2 research reactor sites are being decommissioned by Magnox. These stations are at different stages of remediation, with Bradwell becoming the first NDA site to enter ‘Care and Maintenance’, in 2019.

Following the change of NDA decommissioning strategy from ‘Care and Maintenance’ to rolling decommissioning, it has been announced that Trawsfynydd, in the county of Gwynedd, will undergo a process of accelerated decommissioning and act as the ‘lead and learn’ site. Magnox is in the process of reviewing its plans for the decommissioning of its other sites.
In June 2021, the UK government announced that following closure and defuelling the current fleet of Advanced Gas Cooled Reactor (AGR) stations will transfer to NDA for decommissioning by Magnox. NDA has also announced that Dounreay will cease to follow the Parent Body Organisation structural model and will become a wholly owned subsidiary of NDA. As a result of these two actions Magnox will double in size both in terms of assets, but also in people and funding.
Radioactive Waste Management
The UK Radioactive Waste Inventory is large and complex encompassing materials that require very different approaches in terms of management and disposal.
In recent years, the NDA has moved towards an approach of Integrated Waste Management (IWM). This aims to manage radioactive waste based on its properties rather than solely in terms of the category it is classified as, and to apply the waste hierarchy.
In general, Higher Activity Waste (HAW) will be stored on NDA sites for a number of decades before being consigned to the Geological Disposal Facility. Other material will be disposed of at the national Low-Level Waste Repository (LLWR) in West Cumbria or via a range of treatments and management options including super-compaction, incineration or, in the case of the least radioactive material, appropriately permitted landfill sites.
NDA is also considering a range of other approaches to radioactive waste management. If approved by the UK Government, some radioactive material may be left on-site/in-situ, while the options for the Near Surface Disposal (NSD) of some Intermediate Level Waste (ILW) are being evaluated.
Local Planning Authorities (LPAs) have an important role in the process of decommissioning and waste management, which they regulate through land use and waste plans. Our Radioactive Waste Planning Group (RWPG) provides a forum for officer engagement.
More widely, Nuleaf wants to see all decommissioning and waste management delivering the widest economic, social and environmental gains for nuclear communities and wider society.