Executive summary
- Date(s) of inspection: April 2024
Aim of inspection
This was a planned inspection of EDF Nuclear Generation Limited's (NGL's) implementation of operational arrangements for Seasonal, Severe Weather and Marine Impact Preparations (“Seasonal Readiness”) at Hartlepool Nuclear Power Station (HAR) to ensure that risks associated with seasonal hazards are being adequately managed. Seasonal readiness arrangements include routine and other preparations (e.g., defects and asset maintenance) intended to mitigate risks associated with predictable summer and winter conditions. For example, HAR’s high extreme ambient temperatures (HEATs) justification for continued (JCO) identifies the station’s seasonal readiness arrangements as a mitigation against the hazard’s effects on station safety and safety systems.
Our inspection is intelligence-led and a follow-up to a previous activity in June 2023 (IR-52717), which was undertaken in response to a regulatory issue raised on HEATs. That inspection found that EDF NGL had identified enhancements to its seasonal readiness arrangements and was planning to implement these in future campaigns. Both ONR and EDF NGL’s Independent Nuclear Assurance (INA) function have previously raised concerns in relation to HAR’s seasonal readiness implementation, with INA identifying seasonal readiness as one of the station’s past top risks. This inspection will assess EDF NGL’s enhanced arrangements.
We have assessed the adequacy of EDF NGL’s implementation of seasonal readiness arrangements and their effectiveness in mitigating the effects of seasonal hazards by reviewing compliance against the following licence conditions (LCs):
- LC6 - Documents, records, authorities and certificates.
- LC22 - Modification or experiment on existing plant.
- LC24 - Operating instructions.
- LC28 - Examination, inspection, maintenance and testing.
Subject(s) of inspection
- LC6 - Documents, records, authorities and certificates - Rating: Not rated
- LC22 - Modification or experiment on existing plant - Rating: Not rated
- LC24 - Operating instructions - Rating: Green
- LC28 - Examination, inspection, maintenance and testing - Rating: Green
- Overall Inspection Rating - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
Only those LCs for which sufficient evidence was gathered during the inspection activity have been rated.
LC6 – Not rated. Insufficient evidence was gathered during the inspection activity. We discussed seasonal readiness documentation with the seasonal coordinator, but did not sample sufficient evidence to form a judgement of EDF NGL's compliance with LC6. We advised that EDF NGL should formalise documents and records relevant to seasonal readiness activities.
LC22 – Not rated. Insufficient evidence was gathered during the inspection activity. The inspection activity enabled us to collect intelligence with respect to engineering change commitments and limitations (ECCLs) for engineering changes (ECs) associated with HEATs and flooding hazards. We advised EDF NGL that ECCLs should be progressed in a timely manner. Management of ECCLs will also be discussed with EDF NGL’s Design Authority.
LC24 – Green Rating (No Formal Action). This rating was considered appropriate because EDF NGL has company arrangements for seasonal readiness and has enhanced the implementation of these arrangements at HAR. We advised EDF NGL of gaps that we identified between the company specification and the seasonal readiness process undertaken at HAR. We identified further enhancements that are reasonably practicable including clarifying sign-off requirements for the quality plan, and documenting station-specific instructions and guidance. EDF NGL should identify the adverse conditions that need to be considered for each seasonal readiness campaign and the systems that are susceptible to these conditions. We have raised a Regulatory Issue to ensure these matters are addressed by EDF NGL.
LC28 – Green Rating (No Formal Action). This rating was considered appropriate because EDF NGL provided evidence of inspecting and maintaining systems relevant to seasonal readiness. We sampled plant walkdown reports and were able to trace identified defects into EDF NGL’s work management system. We advised EDF NGL that monitoring equipment used for adverse weather checks should be included on the seasonal readiness routines. EDF NGL could clarify plant walkdown expectations in the context of seasonal readiness arrangements.
Conclusion
We inspected the adequacy of EDF NGL’s implementation of seasonal readiness arrangements at Hartlepool against relevant licence conditions. Overall, the inspection was rated Green (No Formal Action) as no significant issues were raised. We have raised a regulatory issue to ensure EDF NGL address identified gaps in their seasonal readiness arrangements compared with the company specification, and that potential enhancements are implemented in a timely manner. The regulatory issue will be managed as normal regulatory business and we will undertake further follow-up activities in relation to this matter.