Executive summary
Date(s) of inspection: September 2023
Aim of inspection
This is a planned inspection of EDF Energy Nuclear Generation Ltd’s (NGL’s) Heysham 1 Power Station, undertaken as part of the planned intervention strategy for the Operating Facilities Division (OFD) of the Office for Nuclear Regulation (ONR). The work will be carried out in accord with the planned inspection programme contained in the Heysham 1 Integrated Intervention Strategy (IIS) for 2023/24.
Subject(s) of inspection
- LC24 - Operating instructions - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
The inspection was carried out by the ONR HYA Nominated Site Inspector and the Operating Facilties Delivery Management Group Lead for Safety Cases. The inspection comprised discussions with Heysham 1 EDF Energy staff, a review of the records and documents, a walkdown of the ELOG seawater-townswater link and observation of/discussion with central control room staff regarding ELOG procedures and instigation of the seawater-townswater connection.
For LC 24 compliance, we identified no shortfalls requiring regulatory attention. The newly issued and modified OIs associated with the ELOG seawater-townswater link were found to be adequate and implemented in a manner consistent with the dutyholder's arrangements and procedure writing/amendment standards.
In respect of the broader ELOG regulatory issue, RI-10984, we identified no concerns and considered that the capability to operate the seawater-townswater link in the event of a genuine emergency now exists with a high level of confidence. This effectively removes the residual nuclear safety risk associated with the pressure vessel cooling water (PVCW) operability which now meets the ELOG 5-day mission time and takes the dutyholder to an ALARP position with regard to the defence-in-depth for ELOG events.
Conclusion
On the basis of evidence sampled during the inspection, we judged that EDF Energy Heysham 1 was compliant with the requirements of LC 24. We assigned an inspection rating of GREEN in respect of this LC.