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We (The Office for Nuclear Regulation and the Environment Agency) developed the Generic Design Assessment process in response to a request from the Government following its 2006 Energy Review.

GDA includes continued engagement with nuclear reactor design companies, technical assessment work on their submissions, consultation with overseas regulators, a comments process and consultation and reviews of our own processes.

We will not issue permits for new nuclear power stations unless the design and its potential operators meet the high safety, security, safeguards and environmental standards that we require.

Benefits of GDA

  • We get involved with designers at the earliest stage, where we can have most influence.
  • We assess the environmental, safety, security and safeguards aspects of reactor designs before construction of the reactor starts.
  • We provide advice to the designers about any issues we identify so that these can be resolved at the design stage. This increases regulatory effectiveness and efficiency and, for developers, helps reduce their commercial risks on costs and timescales.
  • It separates design issues from specific site related issues, improving the overall efficiency of the regulatory process.
  • It is open and transparent. Anyone can view detailed design information and comment on it. We also give regular feedback on how our assessments are progressing and publish reports at the end of key stages.

How we do GDA

The process has a number of steps, with the assessment getting increasingly detailed. We publish reports at the end of each step which provide an update on the assessment and highlight any concerns or technical issues that have been raised.

ONR carries out its assessment in three steps, while the Environment Agency's process consists of a preliminary and detailed assessment followed by a consultation. Natural Resources Wales (NRW), the environmental regulator for Wales, participates in GDA where a new nuclear power plant design is likely to be proposed for construction in Wales. Additional steps can exist if, after we have completed our assessments, all the issues we have identified are not fully resolved. At the end of the process we will decide if the proposed designs are acceptable for use in Great Britain.

If we receive applications for development of new nuclear power stations at specific sites we will carefully consider those proposals and, take into account the work we have done on GDA, when making decisions about whether the proposals are acceptable.

Our guidance describes the process in detail.

Other permissions needed to build and operate a nuclear power station

Before a new nuclear power station can be built and operated the operator must obtain a number of key site-specific permissions from regulators and Government. These include a nuclear site licence and relevant consents from ONR, environmental permits from the Environment Agency or Natural Resources Wales and planning permission from the Planning Inspectorate.

In both the licensing process and environmental permitting we also assess the capability of the operator and the potential impacts at the site.

Who we are

Office for Nuclear Regulation (ONR)

The Office for Nuclear Regulation is the UK's independent nuclear regulator, with the legal authority to regulate nuclear safety, civil nuclear security and safeguards, and conventional health and safety at the 35 licensed nuclear sites in Great Britain. This includes the existing fleet of operating reactors, fuel cycle facilities, waste management and decommissioning sites, as well as other licensed and, in part, authorised defence sites, together with the regulation of the design and construction of new nuclear facilities. We also regulate the transport of civil nuclear and radioactive materials by road, rail and inland waterways.

The Environment Agency (EA)

The Environment Agency is the environmental regulator of the nuclear industry in England. Its job is to regulate discharges and radioactive waste disposals from nuclear power stations and to ensure their impact on air, water and land is acceptable and minimised.

The Environment Agency also issues and enforces other environmental permits that a nuclear site may need, including permission to draw water from rivers, discharge non-radioactive substances to rivers, estuaries or the sea, treat and dispose of non-radioactive waste and operate 'conventional' plant such as boilers and incinerators.

Natural Resources Wales and the Scottish Environment Protection Agency have similar responsibilities in Wales and Scotland.

Natural Resources Wales (NRW)

Natural Resources Wales is the environmental regulator for Wales and participates in GDA as a partner regulator where a new nuclear power plant is likely to be proposed for construction in Wales. This includes leading on engagement with people in Wales.

Working together

As regulators of the nuclear industry we are working together to ensure that any new nuclear power stations built in Great Britain meet high standards of safety, security, environmental protection and waste management.

Whilst we have independent responsibilities and regulate within our own legal frameworks, we recognise the benefits of building on our close working relationship to align our processes and regulatory positions when we can. We have a joint programme office to plan and administer our nuclear reactor design assessment work.

Office for Nuclear Regulation Environment Agency Natural Resources Wales