Office for Nuclear Regulation

Sellafield annual demonstration of emergency management capability (Exercise DAYLIGHT)

Executive summary

Purpose of Intervention

The Office for Nuclear Regulation (ONR) undertakes all regulatory interactions with Sellafield Limited (SL), the site licensee, against a strategy defined by the ONR Sellafield, Decommissioning, Fuel and Waste (SDFW) Division.  The planned inspection schedule for the current regulatory year (covering April 2019 – March 2020), the content of which is guided by that strategy, identifies the Licence Conditions (LCs) that will be inspected over this period.

This intervention was conducted to determine, through an emergency demonstration exercise, if SL adequately implemented their arrangements to ensure compliance with Licence Condition 11 (Emergency arrangements).  This intervention fulfils the requirement set by ONR for SL to demonstrate their emergency management capability on an annual basis, based on a safety-driven scenario.

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.

ONR’s inspection, which comprised an assessment of a site-wide emergency demonstration exercise (Exercise Daylight) that was planned and managed by the licensee, was completed in accordance with the following ONR guidance:

Through discussion with ONR, SL developed a challenging scenario for this exercise that focussed around a loss of power incident. The scenario was designed to test SL’s emergency capability and response. It had multiple facets, one that related to a specific nuclear facility that experienced challenges on reinstating its power supply, and two others that simulated conventional health and safety responses through an initiating cable strike incident and a simultaneous road traffic accident. The scenario involved significant command and control challenges in terms of casualty recovery, overall emergency response and an associated local facility roll call.  The scenario also required specific nuclear and radiological challenges to be assessed and resolved / mitigated by SL during the course of the exercise.

The exercise was assessed by a multi-discipline team of twelve ONR inspectors located at strategic positions around the site. This team also included three ONR security inspectors who assessed security related aspects of the scenario.

Explanation of Judgement if Safety System Not Judged to be Adequate

Not applicable; this was not a Safety System inspection.

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

This was a challenging exercise scenario that placed demands on facilities across the site, as well as significantly challenging SL’s command and control, Sellafield Fire and Rescue and infrastructure abilities due to the site-wide nature of the simulated events.

I noted some areas of good practice e.g. all casualties were rescued in a timely manner and the command and control performance was judged to be good within the Sellafield Emergency Control Centre (SECC).  A number of learning opportunities were identified as part of the exercise that I will take forward with SL as part of normal regulatory business. 

We welcomed the licensee’s alignment of their self-assessment findings to ONR’s findings, through the licensee being open and self-critical.  

Based on SL’s overall performance throughout the exercise, my assessment team and I consider that SL would have coped adequately had this been an actual event.

Conclusion of Intervention

We shared observations with SL at a debrief session held the following day and welcomed the strong degree of alignment between our own observations and those of SL and their internal regulator.

Overall, based on SL’s demonstration, I consider that the licensee has adequately implemented its arrangements for compliance with LC11 and I have assigned a rating of Green (No formal action) to this inspection.