Office for Nuclear Regulation

Reactor 2 Outage Inspection of the graphite integrity aspects during the 2015 periodic shutdown at Heysham 1

Executive summary

Purpose of intervention

The purpose of this intervention was:

Interventions carried out by ONR

This intervention is one of a number performed by ONR during the periodic shutdown to determine if EDF Energy Nuclear Generation (NGL), the Licensee, has undertaken appropriate inspections in accordance with the safety case and maintenance schedule requirements.  This intervention focused on arrangements for graphite core examination, inspection and testing and the observations made during these periodic shutdown activities.

Key findings, Inspector’s opinions and reasons for judgements made

At the time of my visit, the licensee has completed 12 inspections out of target requirement of 21. There was nothing to suggest that the licensee could not meet the target requirements within the planned schedule.  My visit was however carried out comparatively early in the outage and I am therefore unable to draw final conclusions at this time.  I will subsequently be producing an assessment report to consider whether the work performed was sufficient and whether the findings are consistent with the current safety case.

Based on my questioning of the Licensee’s staff, I consider that those involved have had sufficient training to perform the various tasks relating to the graphite inspections.  I also examined some of the raw visual inspection data and I am content that it is of an adequate quality.

I have made a minor observation relating to training, which I will pursue with the Licensee, but it is not sufficiently serious that ONR should delay the return to service.

I saw nothing of significance to suggest that the adequacy of the graphite inspection activities would prevent a return to service. Therefore I have allocated an IIS rating of adequate.

 Conclusion of intervention

I conclude that the Licensee has made an adequate start to a scheduled programme of graphite inspection.  A forthcoming assessment report will consider whether the results are consistent with the graphite safety case, once the inspection schedule has been completed.