Executive summary
Date(s) of inspection: September 2024
Aim of inspection
This system based inspection (SBI) examined the operation, maintenance and training of the engineered systems associated with monitoring and controlling reactor reactivity. Recognising the large scope of this topic the inspection was divided into three parts:-
- Control Rod Mechanical - 'owned' and built by the Fuel Route Department (SBI OR-23)
- Control Rod Control and Instrumentation (SBI OR-23); Reactivity Monitoring and reactor protection systems (SBI OR-22) - 'owned' by the reactor Protection and Electrical Department
- Diverse Shutdown Systems - 'owned' by the Reactor Systems Department
Subject(s) of inspection
- LC10 - Training - Rating: Green
- LC23 - Operating rules - Rating: Green
- LC24 - Operating instructions - Rating: Green
- LC27 - Safety mechanisms, devices and circuits - Rating: Green
- LC28 - Examination, inspection, maintenance and testing - Rating: Green
- LC34 - Leakage and escape of radioactive material and radioactive waste - Rating: Not rated
- Overall Inspection Rating - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
The key findings from our SBI at Heysham 2 are:
LC 10 – Training: We examined how personnel were deemed to be suitably qualified and experience personnel (SQEP) to undertake examination, inspection, maintenance and testing (EIMT) activities and considered that the associated arrangements were fit for purpose. We examined the training records of personnel who had recently been involved with the maintenance and oversight of equipment from all three systems inspected and generally found that all had completed the essential training to enable them to fulfil their role. Minor shortfalls were observed in relation to the training of technicians building control rods however I was satisfied that the individuals were SQEP and the shortfall was an admin issue associated with a change of the training records computer system. The station is addressing the shortfall.
LC 23 – Operating rules: We reviewed several related technical specifications (Tech Specs) and associated commentaries connected with the systems sampled, and discussed their application with operators. As a result, we considered the Tech Specs and associated commentaries were clear and straightforward to follow.
LC 24 – Operating instructions: We examined the main station operating instructions (SOIs) associated with the systems and discussed their application with operators. A few anomalies were noted but overall we judged that they were logical and easy to follow, even under high workload scenarios.
LC 27 – SMDCs: We reviewed several engineering, operating, and maintenance documents, undertook a plant walkdowns and spoke to several stakeholders. As a result, we judged that the systems were connected and configured correctly, were in working order, and were being adequately maintained. We also judged that an adequate numbers of spares were available for sampled C&I components.
LC 28 – EIMT: We examined several plant item maintenance instructions (PIMIs) and the associated work order cards (WOCs) and checksheets. On the whole, we considered that the associated tasks had been adequately defined; however, we did highlight areas where enhancements could be made. We also considered that, overall, the tasks appeared to have been carried out as specified.
Conclusion
From the evidence sampled during this SBI against LC 10, 23, 24, 27 and 28, we judged that the control rods, reactivity monitoring / reactor safety circuits and secondary shutdown systems are all able to fulfil their safety duties (safety functional requirements) in line with the safety case. No significant issues were raised so green ratings were awarded against all the licence condition samples and I consider that no additional regulatory action is needed over and above the interventions currently planned at HYB. There were however a number of minor regulatory shortfalls observed in relation to a lack of reporting of procedural deficiencies by maintenance technicians and operators and training records. One of these shortfalls in relation to the visibility of chemical 'Certificates of Conformity' (CoC) is being tracked via a regulatory issue.