Office for Nuclear Regulation

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Sizewell C

Current status

On 30 June 2020, ONR received an application from NNB Generation Company (SZC) Ltd for a nuclear site licence to construct and operate a twin EPRâ„¢ power station at Sizewell in Suffolk, adjacent to the existing Sizewell A and B stations. We expect the design of the power station to be closely based on that currently under construction at Hinkley Point C.

In addition to a nuclear site licence, before it can start construction, the applicant must obtain a number of site-specific permissions from other regulators and Government, including environmental permits and planning permission in the form of a Development Consent Order (DCO) from the Secretary of State. NNB Generation Company (SZC) Ltd has recently submitted applications for environmental permits to the Environment Agency and for a DCO to the Planning Inspectorate.

ONR's regulatory responsibility starts at the point of granting of a nuclear site licence for a specified site. If we decide to grant the licence, after our assessment of the application, we will use the powers available under the site licence to permission the start of construction at Sizewell C, and subsequent stages up to the start of commercial operation.

NNB Generation Company (SZC) Ltd is targeting a licence grant by the end of 2021, and we plan to complete our assessment of the application within this timescale, subject to a good quality licence application, informed by continued ONR engagement. 

We will now commence formal assessment of the site licence application, a process that will culminate, if successful, in a recommendation to the ONR Chief Nuclear Inspector on granting the licence. Our publication Licensing Nuclear Installationsprovides guidance on the licensing process and the factors that we may take into account when reviewing an application for a nuclear site licence.

We will undertake our assessment activities in accordance with the guidance provided in the Licensing of Nuclear Installations document and ONR's Safety Assessment Principles, Technical Assessment Guides and Technical Inspection Guides.

The overall outcome of our activities during the assessment phase will be a Project Assessment Report that will draw together the views of ONR's technical specialists, on NNB Generation Company (SZC) Ltd's readiness to become a nuclear site licence holder.

Publication of reports

ONR is committed to being an open and transparent body, and will publish on this website the following material:

FAQs

What is in a Nuclear Site Licence application?

The application is organised into a portfolio of high-level documents, covering a number of technical topic areas, and includes a summary document.

Should it be granted, a site licence puts the licence holder under strict legal obligations and, importantly, gives wider and deeper regulatory powers to ONR to ensure the safe construction, commissioning, operation and eventual decommissioning of a nuclear site.

What is ONR's role?

ONR is the independent regulator for nuclear safety and security for the UK. Our duty is to ensure that the nuclear industry controls its hazards effectively, has a culture of continuous improvement and maintains high standards.

We are responsible for licensing companies that wish to construct and operate new nuclear power stations at sites in Great Britain.

What does ONR look at during the assessment?

We will assess this application, partly informed by our previous assessment of the EPRTM at Hinkley Point C - including using the relevant lessons from that assessment, while focusing on aspects specifically relevant to Sizewell C.

We will request more detail on the areas for assessment and produce inspection reports, the areas for assessment for a nuclear site licence are - organisational capability, site suitability & safe design, licence condition compliance arrangements, emergency preparedness & response, conventional & fire safety, security, safeguards, and licensing & legal aspects.

We need to be satisfied that the applicant's choice of site is suitable; that it understands the hazards and risks of the activities that it proposes to carry out; and that it has a suitable schedule of safety submissions leading through to a pre-construction safety case. 

We place particular emphasis on the need to gain confidence that the applicant has the organisational capability to lead and manage for safety. This means that we must be satisfied with the applicant's governance arrangements, resources, competencies and management processes before we can consider recommending that the Chief Inspector grants a licence.

How long does it take to do the assessment?

The duration of ONR's assessment is dependent on a number of factors, including quality and timeliness of the submissions, and we do not expect to reach any decision until at least the end of 2021.

What happens next?

The overall outcome of our activities during the assessment phase will be a Project Assessment Report that will draw together the views of ONR's technical specialists on NNB Generation Company (SZC) Limited readiness to become a nuclear site licence holder.  

Does this mean they can start to build at Sizewell?

No. The assessment of a nuclear site licence is a significant step, but is not itself permission to start nuclear-related construction. That requires a separate regulatory permission from ONR.

Who else has to give permission for construction to start?

In addition to a nuclear site licence and permission to start nuclear-related construction, before it can start construction, the applicant must obtain a number of site-specific permissions from other regulators and Government, including environmental permits and planning permission in the form of a Development Consent Order (DCO) from the Secretary of State. NNB Generation Company (SZC) Ltd has recently submitted applications for environmental permits to the Environment Agency and for a DCO to the Planning Inspectorate.