Office for Nuclear Regulation & Environment Agency

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Frequently asked questions

Why do we need new nuclear power stations?

The government states that the UK needs new and replacement energy supplies that can provide secure, reliable, low carbon electricity, and that nuclear power should play a part in this.

What is the Office for Nuclear Regulation/Environment Agency's involvement?

ONR and the Environment Agency are working together to assess new nuclear power station designs to ensure that they are safe, secure and environmentally acceptable. They are doing this using a process called Generic Design Assessment ( GDA). The regulators will only conduct GDA on a new power station design following a request from the government.

What is generic design assessment ?

Generic design assessment (GDA) is the process being used by the nuclear regulators ( ONR and the Environment Agency ) to assess the new nuclear power station designs. It allows the regulators to assess the safety, security and environmental implications of new reactor designs, separately from applications to build them at specific  sites.

What are the benefits of Generic Design Assessment? (GDA)

GDA allows the regulators to get involved with designers at the earliest stage, where they have the most influence. By assessing at the design stage, any potential issues can be identified and highlighted so they can be addressed by the requesting parties( the companies who have submitted a design for assessment) before commitments are made to construct the reactors.

How does the Generic Design Assessment work?

ONR are using a step-wise approach with the assessment becoming more detailed at each step. ONR publish their findings in a set of reports at the end of steps 2, 3 and 4. The Environment Agency carries out an initial assessment and a more detailed assessment prior to consulting on its findings. We conduct our work in an open and transparent way.

The government submits a formal request to ONR and the environmental regulators to begin GDA of a new reactor design. The regulators will only commence GDA when this request is received.

Who is paying for GDA?

The assessment and all related costs will be paid for by the power station design companies.

How and to what extent, is security taken into account under GDA?

Security forms a major part of the Generic Design Assessment process and requires the power station design company to submit Conceptual Security Arrangements providing sufficient information to enable ONR to make an informed judgement of the adequacy of the security aspects of the generic design. ONR Security Inspectors work as part of the wider ONR regulatory team to ensure the design company incorporates security by design across the full spectrum of protective security measures, including physical protection, cyber and information and personnel security. The Conceptual Security Arrangements will ultimately form the basis of a Nuclear Site Security Plan for any licensed site using the design.

You say that you are working in an open and transparent way. What does that mean?

As nuclear regulators, we recognise that we are acting in the interests of the public. It is important therefore that we are open about what we do, and how and why we do it. In order to achieve this, we publish extensive information relating to the assessment including technical reports, guidance and regular progress updates through our website and e-bulletin. People also have the opportunity to get involved in GDA via our comments process and the Environment Agency’s consultation.

What does the public comments process involve?

We have asked the designers of the power stations to publish design information on their websites and encourage people to comment.

Q10 - What's the timescale for GDA?

Due to the complexity and the level of scrutiny required in the GDA process it is expected to take around four years to complete, provided the reactor design company meets the timetable for submissions and the submissions are of sufficient detail.

The actual timescale for assessing a reactor design will be largely dependent on the work programmes of the reactor design company, issues that arise from our assessment and its ability to respond to them in a timely way.

Q11 - Under what circumstances would you not issue a GDA confirmation?

If designers do not provide sufficient information, or if our assessment identifies safety, environment or security issues that are so significant that we are not confident that they can be resolved.

Q12 - Where can I find more information on GDA?

In addition to the assessment reports that we publish, we also publish quarterly update reports and offer an e-bulletin service.

Q13 - What is a site licence?

A site licence is a licence that must be granted before a new reactor can be built and operated on a specific site. Before we grant a licence, we will ensure that the site is safe and secure, the site is suitable for the particular design, and that the potential operator can adequately control construction, operation and maintenance of the plant to ensure safety and security.

Q14 - When will site licensing begin?

Site licensing will begin when we receive an application from a potential operator. If a site licence is applied for before the end of GDA, then we will progress this at the same time.

Q15 - What else is required before a nuclear power station can be built and operated?

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. In addition to GDA, 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 Department for Business, Energy & Industrial Strategy's Secretary of State. In both the licensing process and environmental permitting we also assess the capability of the operator and the potential impacts at the site.

Q16 - What is an environmental permit?

A number of specific environmental permits are required by operators so that they can build and operate a new nuclear power station.

If applications for permits are made by a potential operator the Environment Agency or Natural Resources Wales would decide if permits should be issued and, if so, the conditions they include. Operational permits include disposals and discharges of radioactive wastes, operation of standby generators and discharges of cooling water and liquid effluent.

Relevant environmental permits will also be required for the construction and operation of “associated developments” for example infrastructure relating to construction such as workers accommodation or freight transfer facilities.

Q17 - Who decides where the reactors will be built?

In the government nuclear national policy, eight sites were identified as potential suitable sites for nuclear development, all of which are close to existing nuclear licensed sites. Developers put forward their proposals to develop a particular power station design at a specific site, but a power station can only be developed if relevant licences, consents and permits are granted by the regulators.

Q18 - What reactors have been assessed or are currently going through GDA?

The first two nuclear power station designs that were assessed were EDF/AREVA's EPR and the AP 1000 designed by Westinghouse Electric Company. In December 2012 we confirmed that EDF and AREVA's UK EPR reactor design is suitable for construction in the UK and we issued them with a Design Acceptance Confirmation (DAC) and Statement of Design Acceptability (SoDA).  The Westinghouse AP1000 reactor design re-entered the GDA process in August 2014 with 51 outstanding issues remaining.  Following resolution of the issues, we issued Westinghouse with a DAC and SoDA in March 2017. 

We issued a DAC and SoDA for Hitachi-GE's UK Advanced Boiling Water Reactor (UK-ABWR)  in December 2017.

We began Step 2 of GDA for the UK HPR1000 in November 2017.

Q19 - How are Natural Resources Wales ( NRW ) involved in GDA?

GDA is a joint process between the Office for Nuclear Regulation and Environment Agency. Natural Resources Wales, the environmental regulator in Wales since April 2013, is also participating in GDA with the two other regulators and will be leading on engagement with people in Wales.

While the GDA process is generic for England and Wales, it will also underpin the assessments NRW will need to make for the proposed development at Wylfa Newydd. All of the regulators will be working closely together over the next few years.

Q20 - What are regulatory queries, regulatory observations and regulatory issues?

We’ve used a structured approach to raising questions and issues about the designs we are assessing. In brief, RQs are Regulatory Queries where we seek clarification from the designers about their design. ROs are Regulatory Observations reflecting areas where we may have some concerns about the design. RIs are Regulatory Issues that represent a much greater level of concern - sufficiently important that they may, if not resolved, prevent the successful completion of GDA. We publish ROs and RIs on our joint website.