- Site: Hinkley Point B
- IR number: 20-114
- Date: February 2021
- LC numbers: 10, 23, 24, 27, 28
Executive summary
Purpose of Intervention
The purpose of this intervention was to undertake a planned Licence Conditions (LCs) System Based Inspection (SBI) for the Reactor Safety System (RSS) trip parameters at EDF Energy Nuclear Generation Limited’s (NGL) Hinkley Point B (HPB) Power Station.
This work was carried out in line with the planned inspection programme in the HPB Integrated Intervention Strategy (IIS plan) for 2020-21.
Interventions Carried Out by ONR
The objective of this SBI of the RSS was to judge whether the arrangements are adequately implemented and in accordance with the requirements of the relevant safety cases. The RSS primarily monitors reactor or plant conditions and initiates a reactor trip should reference levels of measured parameters be exceeded. Through examination of this system, compliance inspections were performed against LCs which are applicable provisions of the Energy Act 2013.
The inspections were based on sampling the implementation of the licensee’s arrangements at HPB power station against the LCs and was performed in line with ONR’s guides for technical inspections. (www.onr.org.uk/operational/tech_insp_guides/index.htm).
Due to the current government advice on COVID-19 restrictions, the majority of the intervention was carried out remotely using video conferencing with the plant walkdown being the only aspect undertaken at HPB.
The Inspection was undertaken by two control and instrumentation specialists, a fault studies specialist and the nominated site inspector.
Explanation of Judgement if Safety System Not Judged to be Adequate
From the intervention and details examined, we judge that the arrangements associated with the RSS are adequately implemented and consistent with the safety case requirements.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
From the System Based Inspection of the RSS, we made the following conclusions:
- LC10 (Training) – We examined the training records of a number of personnel involved in operations and maintenance activities associated with the reactor safety system trip parameters. We were satisfied that EDF NGL have made and implemented adequate arrangements for suitable training. Therefore, we judge the inspection rating of LC10 is green.
- LC23 (Operating Rules) – We examined the relevant safety cases, technical specifications and the associated documents. We were satisfied that EDF NGL have adequate arrangements to implement the identified conditions and limits necessary in the interests of safety. Therefore, we judge the inspection rating of LC23 is green.
- LC24 (Operating Instructions) – We examined relevant safety operating instructions (SOIs) related to the RSS trip parameters. We were satisfied that the sampled operations were carried out in accordance with the relevant SOIs. Therefore, we judge the inspection rating of LC24 is green.
- LC27 (Safety Mechanisms, Devices and Circuits) – We examined the system health and areas related to the RSS. We were satisfied that EDF NGL had implemented appropriate arrangements to ensure that the safety mechanisms, devices and circuits were properly connected and in good working order. This was supported by the evidence seen during the plant walkdown. Therefore, we judge the inspection rating of LC27 is green.
- LC28 (Examination, Inspection, Maintenance and Testing) – We examined relevant parts of EDF NGL’s maintenance schedule, a number of work order cards and work instructions. We were satisfied that EDF NGL have made and implemented adequate arrangements for the systematic examination, inspection, maintenance and testing of the areas related to the RSS. Therefore, we judge the inspection rating of LC28 is green.
- LC34 (Leakage and Escape of Radioactive Material and Radioactive Waste) – The RSS does not contain radioactive material or radioactive waste so LC34 was not considered applicable to this SBI.
The intervention findings were shared with EDF NGL. They have satisfactorily responded to the majority of these findings during the intervention. There remain a few minor observations to be addressed by EDF NGL and they will be managed by the nominated site inspector via routine regulatory engagement.
Conclusion of Intervention
From the evidence examined during this intervention, we judged that there were no matters that have a significant adverse impact on nuclear safety. We consider EDF NGL have adequately implemented their arrangements to ensure nuclear safety is maintained. There was no formal regulatory action raised from the outcomes of this intervention. We judge the overall inspection rating is green.