Executive summary
Date(s) of inspection:
September 2025
Aim of inspection
In accordance with the Office for Nuclear Regulation’s (ONR’s) Dungeness B (DNB) intervention plan, ONR performs a series of planned compliance inspections of identified licence conditions (LCs) and other applicable legislation, to ensure that DNB is meeting its legal requirements.
The aim of this inspection was to ensure that Dungeness B (DNB) is managing its maintenance activities appropriately and ensuring that required maintenance and any defects are being addressed in a timely and appropriately prioritised manner. This intervention focused on the following aspects, maintenance/work management oversight including defect management, prioritisation and delivery of rectification/repairs.
Subject(s) of inspection
- LC28 - Examination, inspection, maintenance and testing - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
Licence condition 28 requires that the licensee shall “shall make and implement adequate arrangements for the regular and systematic examination, inspection, maintenance and testing of all plant which may affect safety.”
From the evidence sampled I noted that:
Dungeness B has appropriate oversight and management of maintenance and safety significant defects.
Dungeness B has implemented appropriate arrangements for maintenance schedule suspensions; however, I noted subsequent revision control could be improved.
Defect backlog is reviewed and is being managed to ensure there is no significant impact on safety.
Statutory defects are generally appropriately managed however ONR noted that improvements could be made to the management of non-safety significant lift defects to ensure that all relevant defects are addressed during maintenance periods.
Dungeness B has appropriate strategies for optimising maintenance in support of defueling.
Conclusion
I judge that Dungeness B was able to demonstrate that overall, it was adequately implementing its Licence condition 28 arrangements in relation to maintenance delivery/defect management and hence consider that a Green rating (no formal is required) is appropriate.
I identified a number of relatively minor areas for improvement, and the station promptly addressed the majority of these, however I have raised a level 4 issue to ensure regulatory oversight of improvements in relation to LOLER related defect work packaging. This improvement area does not affect the overall rating of Green.