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Sellafield is a large and complex site and one of Europe's largest industrial complexes, managing more radioactive waste in one place than any other nuclear facility in the world.

Many of the facilities on the site are ageing, and new facilities are required, as the site’s mission changes from reprocessing to decommissioning. Reducing the hazard and risk on the Sellafield site safely and securely is both a national priority and one of our top regulatory priorities.

Our regulation of Sellafield covers two well defined areas:

Project delivery

Focuses on priority areas, concentrating efforts on facilities and processes requiring the greatest improvement, with a view to accelerating overall hazard and risk reduction. Some of the ways we do this, include:

  • Influencing Sellafield Ltd in delivering safe, secure, effective and timely plans to achieve hazard and risk reduction on site;
  • Working constructively with Sellafield Ltd to make regulatory expectations clear whilst maintaining appropriate regulatory independence and oversight;
  • Assessing and granting permission to implement safety cases that support hazard and risk reduction on the site. Safety is our overriding priority, so we will only permit activities to take place if we are satisfied that it is safe to do so; and
  • Working constructively with other stakeholders as part of the ‘G6’ stakeholder group to accelerate hazard and risk reduction at the site.

Compliance, intelligence and enforcement

Regulates site-wide safety at Sellafield through consistent and targeted application of our regulatory standards.  This ensures that Sellafield Ltd maintains adequate levels of overall site safety whilst hazard and risk reduction work is underway at a number of key facilities. Our regulatory teams:

  • Undertake a programme of targeted planned and reactive inspections to monitor compliance with the law.  Our inspectors carry out compliance inspections, systems-based inspections, and also assess emergency exercise performance;
  • Investigate incidents, respond to intelligence and engage with the local community group and worker and safety representatives; and
  • When shortfalls are identified take proportionate action to restore legal compliance.

ONR's strategy for regulating Sellafield

Our regulatory strategy aims to help drive improvements at Sellafield, and facilitate and encourage hazard and risk remediation whilst maintaining adequate safety standards.