Office for Nuclear Regulation

Hinkley Point B Power Station – Reactor 3 Outage - Graphite Intervention

Executive summary

Purpose of intervention

The purpose of this intervention was to undertake a Licence Condition (LC) 28 compliance inspection at EDF Energy Nuclear Generation Ltd’s (NGL’s) Hinkley Point B (HPB) power station, in line with the planned inspection programme contained in the HPB Integrated Intervention Strategy (IIS) for 2015/16.

Interventions carried out by ONR

This intervention is one of a number of LC28 compliance inspections performed by ONR during the periodic shutdown of Reactor 3 to inform the ONR decision whether to issue a licence instrument granting consent for the return to service of HPB Reactor 3 (R3) following its 2016 statutory outage.  This intervention specifically 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 the visit, the licensee had completed 1 visual inspection and bore measurement, out of a target requirement of 31. The inspection program had been on schedule so far. During the intervention, I was made aware that the licensee had optimised the inspection program taking account of the logistics of the arrangement of the inspection equipment. I was satisfied that the licensee was in an adequate position to complete all the planned inspections and measurements.  An assessment report will be produced subsequently to consider whether the work performed was sufficient and whether the findings are consistent with the current safety case.

I considered that the personnel involved in undertaking inspections and measurements have had sufficient training to perform their various tasks.  I also examined some of the visual inspection data and I am content that it is of the necessary quality.

In light of the observations made during the inspection, I have allocated an IIS rating of ‘3 - adequate’.

Conclusion of intervention

Based on the observations I made during the intervention, I conclude that the licensee has demonstrated compliance with LC28 and I judge that the licensee is in an adequate position to complete its full scheduled programme of graphite inspections.  A forthcoming assessment report will consider whether the results are consistent with the graphite safety case, once the inspection schedule has been completed.