The UK Office for Nuclear Regulation (ONR), the Environment Agency and Natural Resources Wales (NRW) announced that they are progressing to the next phase of their assessment of Holtec International’s Small Modular Reactor (SMR) design.
The Generic Design Assessment (GDA) process allows the regulators to begin assessing the safety, security, safeguards and environmental aspects of new reactor designs before site-specific proposals are brought forward. It is a voluntary, non-mandatory process aimed at providing early confidence that a proposed reactor design is capable of being constructed, operated and decommissioned in accordance with the high standards of safety, security, environmental protection and waste management in Great Britain.
Step 1 of the GDA for Holtec began in October 2023 and focused on agreeing the scope and schedule for Step 2. This stage has now been completed, marking the start of the fundamental assessment of the design (Step 2) which is expected to last for 14 months.
Agreeing the scope of the GDA throughout Step 1 was based on information supplied by Holtec to the regulators so they can undertake a meaningful assessment of the design. ONR said Holtec has completed all the requirements for Step 1 from the regulators’ guidance with good progress made in developing its organisation and arrangements to support GDA.
Holtec has now launched a comments process on its new website, which enables anyone to submit comments and questions about the reactor design to the company for its response. Relevant issues raised during the comments process, and Holtec’s responses to these issues, will be used to help inform the regulators’ assessments throughout the rest of the GDA process.
“GDA is a vital part of ensuring new reactor designs meet the high standards of safety, security and environmental protection required in Great Britain,” said Tim Parkes, ONR’s Head of Safety Regulation for Advanced Nuclear Technologies and the Holtec SMR-300 GDA. “Together with the Environment Agency and Natural Resources Wales, we have seen Holtec demonstrate readiness to move into Step 2 of the assessment where we can begin the technical assessments of the reactor.”
He added: “Throughout Step 1 Holtec has been mobilising its delivery organisation to complete the GDA and we have been agreeing the scope for our assessment in Step 2. We have improved our understanding of the generic SMR-300 design which will enable us to conduct a meaningful assessment throughout Step 2.”
He noted: “Safety and security will always be our overriding priority, but we are committed to regulating in a way that does not impede technological advancements unless it is fully justified that we do so. We will continue to engage with the US Nuclear Regulatory Commission about potential collaboration and information exchange on the review and assessment of the SMR-300 design.”
Saffron Price-Finnerty, the Environment Agency’s New Reactors Programme Manager said: “We’re assessing the environmental acceptability of a new Small Modular Reactor design from Holtec International based in the US, working with Holtec Britain, which is managing the delivery of the GDA in the UK. Holtec Britain has worked hard to grow the company sufficiently to be able to effectively manage and deliver the project.”
She added: In our Step 1 statement we’ve summarised what we have looked at and concluded that we can progress to Step 2 of GDA where we will begin our fundamental assessment. We have also agreed the GDA scope and we are satisfied that all of the main systems from an environmental and waste management perspective are included within the assessment scope…. This is a 2-Step GDA which won’t include a public consultation, so it’s even more important for people to get involved in the comments process.”
Natural Resources Wales (NRW) is also involved in the GDA process where there is a possibility the reactor design could be deployed in Wales, and will be leading on engagement with stakeholders in Wales. Paul Gibson, the NRW Radioactivity & Industry Policy Team Leader said: “As we have now reached the end of Step 1, we will continue working closely with our partners as the project progresses to fundamental assessment of the design in Step 2.”
GDA is a flexible process with up to three steps. The assessment becomes increasingly detailed with each step. A Design Acceptance Confirmation (DAC) or Statement of Design Acceptability (SoDA), from ONR and the environmental regulators respectively, is issued at the end of the process when the design meets the high safety, security, safeguards, environmental protection and waste management standards expected by our regulatory frameworks.
ONR noted: “As Holtec is undergoing a two-step GDA for its SMR-300 design, no DAC or SoDA will be issued and our assessment will stop at the end of Step 2. At the end of Step 2 the regulators will issue a GDA Statement, indicating their level of confidence in whether the SMR-300 design can potentially be built, operated and decommissioned in Great Britain in a manner that is safe and secure.”
Holtec’s GDA is the first that is planned to finish at the end of Step 2. Should the company wish to continue its plans to build a small modular reactor in England or Wales, a further period of detailed design assessment will be carried out by the regulators, either as part of a future Step 3 or as part of a site-specific development.
“We are pleased to report that Holtec Britain, a wholly owned subsidiary of Holtec International (USA), has set a new record for expeditious regulatory approval by completing the first part of the UK Generic Design Assessment process (GDA) for its SMR-300 nuclear reactor in a mere 10 months, Holtec noted.
The SMR-300 is a pressurised water reactor (PWR) using technology based on existing standards in the US and UK and uses PWR fuel similar to that already used at Sizewell B, and other new UK reactors under development including Hinkley Point C. Holtec has been developing its SMR since 2011. The SMR-300 has undergone several design evolutions, the most recent of which is the incorporation of forced flow capability overlayed on gravity-driven flow in the plant’s primary system.
Holtec Britain was supported by a £60m ($76.8m) investment, £30m of which was secured from the UK government’s Future Nuclear Enabling Fund award in 2023. The Holtec Britain team has now more than tripled in size and has relocated its UK HQ to Bristol. “We are pleased by the UK regulators’ affirmative assessment of Holtec Britain, which is backed by its US parent as well as Team Holtec members Hyundai Engineering and Construction Co of Korea and Mitsubishi Electric Co. of Japan,” Holtec said.
Holtec plans to establish a heavy manufacturing plant in theUK to build SMR-300 components mirroring existing plants in the US. Selection of the most suitable site for the manufacturing facility is underway. Holtec aims to begin the licensing and construction of two SMR-300 units at the company’s Palisades site. The shovel-to-startup life cycle of the first batch of SMR-300s is expected to be three years.
