This intervention is part of the Sellafield Programme of inspections looking at Periodic Safety Reviews and specifically considered the B268 (including B269) Long Term Periodic Review (LTPR). This is part of the Magnox complex of facilities and was selected for inspection to check whether lessons leant from the other Magnox LTPRs had been incorporated into this LTPR. The facility is operated by Sellafield Ltd. (SL) as the Licensee. The emphasis of this intervention is on ensuring SL have a credible extant safety case which allows it to continue to operate the plant in a manner that maintains the plant risks as low as reasonably practicable (ALARP).
This inspection looked at compliance with Licence Condition (LC) 15 (the requirement to undertake Periodic Safety Review of the safety case) and followed the lines of enquiry recommended in a fault studies scoping report namely:
In addition to conducting the inspection of the facility, we attended a series of presentations on the B268 LTPR and its implementation and held detailed discussions on three high consequence fault sequences.
This was a successful intervention with good cooperation between all parties. The inspection revealed that SL had undertaken a pragmatic LTPR which resulted in the licensee identifying 3 Safety Significant Improvements and 35 Lesser Safety Significant Improvements. Our inspection did not reveal any matters of substantive concern that had not already been identified by the licensee in its own review.
Based on the limited sample undertaken, the team considered that SL had undertaken a reasonable LTPR of B268. Through our discussions of high impact fault sequences the team established that SL had considered potential improvements and noted that, because of the facility's age and limited remaining operation, these tend to be biased towards OPMs (Operational Protective Mechanisms, i.e. administrative rather than engineered safety measures). As a consequence we welcomed how SL have integrated HF assessments into the LTPR, particularly in respect to substantiating OPMs.
No further action is required in response to this inspection. SL will produce a Confirmation of Safety Letter (COSL) to confirm the facility has adequately implemented the LTPR, which will allow them to continue to operate the plant in a manner that maintains the plant risks as low as reasonably practicable (ALARP).