Office for Nuclear Regulation

Sellafield – Inspection ID: 22-039

  • Site: Sellafield
  • IR number: 22-039
  • Date: June 2022
  • LC numbers: 11

Executive summary

Purpose of Intervention

This intervention record covers the planned inspection of Exercise SIERRA LIMA 2, a Sellafield Ltd Level 1 safety demonstration exercise. The purpose of the intervention was to evaluate the adequacy of existing arrangements to ensure compliance with Licence Condition 11.

Interventions Carried Out by ONR

Licence Condition 11 (LC11) requires the licensee to make and implement adequate arrangements to deal with any accident or emergency arising on the site and to ensure that such arrangements are rehearsed periodically.

The exercise was assessed by a multi-discipline team of nine ONR inspectors located at strategic positions around the site. Our inspection was completed in accordance with the following ONR guidance:

  • NS-INSP-GD-011, Revision 7.1, March 2021 – Emergency arrangements.

Explanation of Judgement if Safety System Not Judged to be Adequate

No applicable; this was not a Safety System inspection.

Key Findings, Inspector’s Opinions and Reasons for Judgements Made

Sellafield Ltd demonstrated their emergency arrangements with an exercise involving a criticality event during silent working hours. The scenario was technically complex and provided a challenge to the responders. ONR welcomes demanding exercises as they generally uncover greater learning opportunities.

The exercise objectives were achieved with various associated learning opportunities. There were a number of areas of good practice with effective situational briefing to emergency responders, prompt evacuation and casualty triage. There were demonstrations of capability from key players and a continual consideration of security throughout the exercise.

Sellafield Ltd self-identified learning opportunities associated with the interface between the tactical (front-line) organisation and the Site Emergency Control Centre (SECC). Sellafield Ltd intends to ensure that the lessons from this exercise are taken forward and will consider appropriate opportunities for ONR to attend future exercising activities to demonstrate that the learning from this exercise has been considered and embedded (where appropriate).

Conclusion of Intervention

We consider that this was an adequate demonstration warranting an intervention rating of GREEN (no formal action required) for LC11.