Our role in nuclear regulation

Our environmental regulation of nuclear sites covers the full life-cycle from construction, operation and decommissioning to final clean-up of the site in close partnership with our partners the Office for Nuclear Regulation (ONR) who regulate nuclear safety and security.  As well as the work we carry out for the environmental regulation of specific nuclear sites in Wales, we work extensively with our partners in England, Scotland and Northern Ireland on matters which apply across the whole nuclear sector in the UK.

We work with designers, operators, developers, regulatory partners and Government Departments (UK and Welsh Government) across a multitude of policy, strategy and legislative frameworks.  This includes planning for and determining changes to UK and European legislation and how that might affect the regulation of the nuclear sector in Wales.  Subjects include work related to the current and future strategies for the storage and disposal of radioactive wastes in the UK, the future use of nuclear energy and nuclear medicine, nuclear research and development and other key aspects of the nuclear sector that needs to be considered and regulated. 

Existing Nuclear Licensed Sites

NRW has responsibility for issuing, regulating, and enforcing environmental permissions to operators of existing nuclear sites in Wales and regulating compliance against the limits and conditions within their permits.

There are currently two nuclear licensed sites in Wales.  Both sites are located in North Wales, at Trawsfynydd and Wylfa and historically produced electricity generated from nuclear power.  Both legacy sites are being decommissioned by the operator, Magnox Ltd, a subsidiary of the U.K Nuclear Decommissioning Authority (NDA) and we regulate compliance against the environmental permits we issued to them.  NRW has a strong relationship with its regulatory partners the ONR and the Environment Agency (EA) to provide appropriate and effective regulatory scrutiny of our Welsh nuclear sites. 

This multi-agency approach has been demonstrated through the successful regulation and delicensing of the former Cardiff G.E Healthcare radiopharmaceutical production nuclear site in South Wales.  In 2019, radioactive wastes were removed from the site and final site clean-up took place under the regulatory scrutiny of NRW, EA and the ONR.  In late 2019, after extensive review, NRW’s permitting team with support from the EA, issued a site environmental permit surrender notice on the basis that all disposals of radioactive waste ceased and the condition of the site provides an appropriate level of protection of people and the environment.  Additionally, the ONR delicensed the site on the basis there ceased to be any danger from ionising radiation per the no-danger requirement under the U.K. Nuclear Installations Act.  Therefore successfully bringing radioactive substances regulation at the site to an end after 40 years. 

New Nuclear Installations

Environmental Permitting and Planning

We are responsible for the environmental permissions relating to the construction and operation of any new nuclear installations in Wales.  Any company that wishes to construct and operate such an installation will need to apply to us for a range of environmental permissions that may include environmental permits, licences and consents.  These permissions may also apply to relevant associated developments such as workers’ accommodation and park and ride facilities to support construction.

We will give advice and guidance to developers before they apply for permissions. Once they are submitted to us, we will conduct a detailed assessment programme and decide if the permissions should be issued and what specific conditions should be applied. 

We are consulted by both planning authorities and developers for our expert advice on likely environmental effects from development proposals.  We also advise local planning authorities preparing local development plans.  We will consult with stakeholders and the public on our work during both a Generic Design Assessment of a nuclear reactor design, and any site-specific programme.   We will publish an engagement plan to inform people of how we will communicate and consult with them. 

Generic Design Assessment (GDA)

The Generic Design Assessment (GDA) is a voluntary process to assess new nuclear power plant designs. A reactor designer, the Requesting Party, applies to the UK Department for Business, Energy and Industrial Strategy (BEIS) to enter the process.  The GDA process itself is led by the Office for Nuclear Regulation (ONR), for safety and security, and by the EA for environmental considerations.

NRW will join the environmental assessments to establish acceptability of a generic design from a Wales perspective.  The GDA allows the nuclear regulators (ONR, EA and NRW) to assess the safety, security and environmental implications of new reactor designs separately from applications to build them at specific sites.  Through the GDA process potential regulatory design or technical issues can be identified early.

The GDA progresses through 3 Steps of increasing levels of scrutiny, from Step 1: Initiation, to Step 2: Fundamental Assessment and Step 3: Detailed Assessment, over the course of approximately 4 years.

The precise length of each Step is decided in mutual agreement between the regulators and the Requesting Party as part of Step 1 negotiations. The Requesting Party also has the option to pause or stop the GDA between Steps.  At the end of Step 3, if the regulators are satisfied that the reactor design can meet the required standards for safety, security and environmental protection, then a Design Acceptance Confirmation (DAC) will be issued by the ONR and a Statement of Design Acceptability (SoDA) will be issued by the environmental regulators.

Further site-specific assessments and permissions, which are informed by the findings of the GDA, are required for a given site.  Additional guidance on the GDA process can be found here on the UK Government website.

The GDA of the 470 MWe Rolls-Royce Small Modular Reactor (RR SMR) design, requested by Rolls-Royce SMR Ltd, began in April 2022.  RR SMR Ltd intends that it completes all three steps of the GDA process with the objective of securing a Statement of Design Acceptability (SoDA) from the environment agencies and a Design Acceptance Confirmation (DAC) from ONR. 

Find additional information on progress on the RR SMR GDA on the UK Government website


Find more information on the joint regulators’ website

Find further information about the reactor design on the Rolls-Royce SMR website.

Other Regulatory Work Related to the Nuclear Sector in Wales

Our work on environmental regulation of existing and new nuclear developments in Wales includes,

  • providing information about the environment around potential sites so developers can make sound decisions to protect and enhance our natural habitat
  • undertaking environmental monitoring and publishing the results in the annual ‘Radioactivity in food and the environment (RIFE) report’
  • advising on the scope of developers’ Environmental Impact Assessments and providing information for the assessments
  • regulating site investigation works that are needed to check sites are suitable for development
  • providing pre-application advice
  • responding to consultations run by government, developers and local authorities
  • advising on flood and coastal risk matters for development sites, including associated developments away from the main power station site, for example workers’ accommodation
  • providing advice and information to the planning inspectorate about planning and our regulatory matters
  • regulating the sites for environmental matters during their construction, operation and decommissioning phase

Geological Disposal Facility (GDF)

The Welsh Government has adopted a policy of supporting geological disposal for the long-term management of higher activity radioactive waste.  This is in line with the UK Government’s overarching approach for managing higher activity radioactive waste in England, Wales and Northern Ireland through geological disposal.

A GDF will only be built in Wales if a community is willing to host one and a suitable and safe site can be found, the process of selecting a site in Wales is consent-based. 

Following a public consultation that ended in 2018, the Welsh Government has launched a policy that outlines the engagement process for communities in Wales who wish to enter into discussions to explore potentially hosting a geological disposal facility (GDF). This follows a similar process launched by the UK Government in December 2018, for communities in England.

The UK Government funded programme to deliver a single GDF for the high activity waste produced in Wales, England and Northern Ireland, will be delivered by Nuclear Waste Services (NWS) a subsidiary of the Nuclear Decommissioning Authority.  NWS is responsible for implementing geological disposal and they will lead the siting process, working in partnership with communities to identify a suitable location to host a geological disposal facility.

If a site for a GDF was identified in Wales, planning permission would be needed as well as site specific safety and security permits from the ONR and the relevant environmental permits from NRW.  As with nuclear sites currently in Wales, we would work closely with the ONR to jointly regulate a GDF.  If a site were identified in England, these roles would be undertaken by the Environment Agency and ONR.

Our responsibility would be making sure that the developer and operator of a GDF in Wales meets the high standards we require to protect people and the environment, both now and for future generations. We do not have a role in the decision to select a GDF site.  We will be available to provide information and advice to communities on our role in environmental protection throughout the site evaluation process.

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