Office for Nuclear Regulation

Sellafield – Inspection ID: 52119

Executive summary

Date(s) of inspection:

  • June 2023

Aim of inspection

In accordance with the Office for Nuclear Regulation’s (ONR’s) Sellafield Strategy, each year ONR performs a series of planned inspections to seek assurance of compliance against selected licence conditions, targeted at those facilities with significant importance to nuclear safety. One such inspection was undertaken at  Special Nuclear Materials Value Stream (SNM) facilities at North and South within the Sellafield site in West Cumbria  to sample evidence of implementation of Sellafield Limited’s arrangements for compliance with Licence Condition (LC) 28 (examination, inspection, maintenance and testing)  in order to inform a regulatory judgement regarding the licensee’s compliance with its legal duties under the nuclear site licence.

Subject(s) of inspection

  • LC28 – Examination, inspection, maintenance and testing – Rating: Green

Key findings, inspector’s opinions and reasons for judgement made

The inspection was undertaken on 14  and 15  June 2023 by the SNM site inspector, a civil engineering specialist inspector and a safeguards inspector. The inspection targeted compliance against Licence Condition (LC) 28 (examination, inspection, maintenance and testing). The inspection focused on civil structures in the Special Nuclear Materials Value Stream (SNM) North and South facilities on the Sellafield site.

The inspection involved a planning phase and a two‑day site visit, including plant walkdowns, discussions with relevant Sellafield Limited personnel, review of records, and sampling of information contained within electronic databases and other documentation.

Overall, we were satisfied that  the licensee provided an adequate level of assurance and evidence to demonstrate compliance with LC28. Examination, inspection, maintenance and testing was being undertaken in an appropriate and timely manner.

Sellafield Limited recognised that a number of system health reports are outdated and provided assurance that the reports will be updated, and that all maintenance issues have been captured and prioritised as appropriate.  A Level 4 regulatory issue has been raised to  manage the implementation of this area of improvement.

Based on the training evidence sampled we were satisfied that the selected personnel were suitably qualified and experienced for the task and their training was found to be in date.

Whilst the licensee appears to have a robust process for raising,  sentencing and prioritisation of maintenance  issues, raised from their inspections, implementation of solutions depends on funding and resources at value stream portfolio  and at enterprise level.  This was evident in facilities at SNM South where water ingress from roofs was apparent. A Level 4 issue has been raised to  manage the implementation of improvements of asset care for roofs at SNM South.


On the basis of evidence sampled and the interactions that we held with Sellafield Limited staff, at the time of the inspection, we judge that, on balance, Sellafield Limited has largely  implemented its arrangements for compliance with LC28 (Examination, inspection, maintenance and testing). Upon consideration of the ONR guidance on inspection ratings, we judge that a rating of green (no formal action) is appropriate.

We have identified two minor shortfalls: one related  to the review and updating of system health reports, and one to address the roofs asset care at SNM South.  I have raised two level 4 (lowest level) regulatory issues to track resolution of these shortfalls.