Effective Regulation of Nuclear Reactor Decommissioning: Ensuring Safety and Compliance

Transitioning Hinkley Point B into Decommissioning Phase

In 2022, after an impressive 46 years of operation, Hinkley Point B (HPB) ceased operations at its final reactor and commenced the defueling process. By January 2026, the Office for Nuclear Regulation (ONR) confirmed that the site was free of nuclear fuel. Alister, the nuclear regulator for Hinkley Point B, elaborates on the role of the Environment Agency in overseeing the power station as it embarks on the next phase of its nuclear lifecycle.

On 1 October 2026, the environmental permits for Hinkley Point B were officially transferred from EDF to Nuclear Restoration Services (NRS), signalling the beginning of a new chapter in the decommissioning journey. This transfer marks a significant milestone, as HPB becomes the first Advanced Gas-Cooled Reactor (AGR) in England to transition under NRS’s stewardship, following Hunterston B in Scotland, which completed its transfer in April.

The Regulatory Journey of Hinkley Point B

Hinkley Point B commenced operations in 1976, and throughout its operational life, the framework governing environmental law and protection has undergone significant evolution, reflecting advancements in scientific understanding. Prior to 1996, most environmental oversight at HPB was conducted by Her Majesty’s Inspectorate of Pollution (HMIP) and its predecessors. A pivotal shift in the regulation of nuclear power stations occurred in 1996 with the establishment of the Environment Agency.

Over the past 30 years, the Environment Agency has maintained regulatory oversight of Hinkley Point B. Operators of nuclear facilities are required to secure an environmental permit for activities involving radioactive substances (RSR). The RSR permit for HPB encompasses stringent conditions that operators must adhere to at all times, including limits on emissions during activities such as radioactive waste disposal and discharges into air and water.

In June 2025, EDF requested modifications to its radioactive substances permit as the reactors were no longer operational and the site had been rendered fuel-free. Such adjustments are necessary to reflect the current activities and the diminishing radiological risk associated with HPB. Similar amendments are being observed at other facilities transitioning through decommissioning stages.

Collaboration and Compliance During Decommissioning

In July 2025, we received a joint application to transfer the radioactive substances permit from EDF to NRS. This process has involved extensive collaboration, with the Environment Agency working alongside colleagues in the Wessex area and the National Permitting Service to also transfer the Water Discharge Activity Permit, two closed landfill permits, a Combustion Activity Permit, and a water abstraction permit. Furthermore, the permit for the District Survey Laboratory at Combwich was surrendered, as laboratory operations transitioned to the HPB site. EDF provided evidence of the absence of radioactive materials and contamination within the laboratory through a conclusive radiological survey.

Our regulatory framework requires HPB to monitor its radioactive discharges and waste meticulously. We also conduct independent monitoring to ensure compliance and reassure the public, with the findings disclosed in our annual reports.

Future Regulatory Oversight at Hinkley Point B

Looking ahead, the Environment Agency will continue its regulatory oversight throughout the decommissioning process, prioritising environmental protection and the responsible management of radioactive waste, alongside considerations for sustainability and climate change adaptation.

Our extensive experience in regulating decommissioning nuclear facilities, as demonstrated by the ongoing work at Hinkley Point A (HPA), will guide our efforts. Since HPA ceased operations in 2000, significant changes have taken place, including the removal of equipment, the establishment of waste treatment and storage facilities, and land remediation efforts.

During the decommissioning phase, activities will focus on minimising hazards, both radiological and chemical. Following the defueling of HPB, efforts have been directed towards eliminating environmental hazards, including the bulk storage of oils and chemicals. This year, our regulatory focus has centred on ensuring EDF’s compliance with existing permit conditions, facilitating the permit transfer, and confirming that the transition from EDF to NRS aligns with our stringent requirements.

Engagement and Community Communication

As we progress, our initial focus will be on assessing how effectively the site has transitioned under new management. Our role is to ensure that the operator has successfully managed this change process while remaining compliant with our permits. We aim to extract valuable insights that can inform the permit transfer process for the remaining AGR fleet. NRS will also be developing decommissioning plans, and we will provide necessary guidance to ensure compliance with permit requirements and best available techniques (BAT).

Community engagement will remain a crucial aspect of our responsibilities. We will continue to host ‘meet the regulator’ meetings, participate in the Site Stakeholder Group, and respond to inquiries from the community regarding our regulatory activities concerning HPB.

If you have any questions about our work at Hinkley Point B, please reach out to us at nuclear@environment-agency.gov.uk.