The purpose of this intervention was to undertake a system based inspection of the main electrical systems at EDF Energy Nuclear Generation Limited's (NGL's) Heysham 1 power station and a licence compliance inspection in line with the planned inspection programme contained in the Heysham 1 Integrated Intervention Strategy (IIS) for 2016/17.
The ONR Nominated Site Inspector, an ONR Electrical Engineering Specialist Inspector and the ONR Site Inspector for AWE Burghfield performed a System Based Inspection (SBI) of the main electrical system to judge the system performance against its safety function.
The ONR Nominated Site Inspector, supported by an ONR leadership for management and safety specialist inspector also carried out an LC36 - Organisational capability compliance inspection.
In addition both the ONR nominated site inspectors for Heysham 1 and Heysham 2 attended the Local Community Liaison Committee (LCLC) meeting
Following a system based inspection of the main electrical system, we judge that overall this system meets the requirements of the safety case and is adequate.
Through examination of the main electrical system and associated sub-systems we performed compliance inspections against licence conditions LC10 (training), LC23 (operating rules), LC24 (operating instructions), LC27 (safety mechanisms, devices and circuits) and LC28 (examination, inspection, maintenance and testing). In this case LC34, which relates to leakage and escape of radioactive material and waste is not applicable to this system and therefore deemed not applicable to the inspection. The inspections undertaken were based on sampling the implementation of the arrangements in place at the station against each licence condition.
From the areas sampled it was judged that Heysham 1 has suitable arrangements to ensure that the main electrical system is maintained and operated in accordance with the requirements of the safety case and that they are implemented appropriately. The inspection did, however, identify improvements that could be made to the quality of the maintenance records. These shortcomings have been identified during previous ONR inspections and, although the station has recognised these shortcomings and put in place an improvement plan, ONR regulatory issue 4607 has been raised to monitor the progress with the improvement plan.
Notwithstanding this issue, overall it was judged that the arrangements for safe operation of the main electrical system and their implementation generally meet relevant good practice and therefore we have given IIS ratings of Green in relation to compliance with LCs 10, 23, 24, 27 and 28.
The purpose of the LC36 compliance inspection was to review the adequacy of the Management of Change (MoC) progress and maintenance of the station nuclear baseline. From a review of a number of recent MoC documents and station roles we judged that the LC36 arrangements and their implementation met the expected standard and therefore an inspection rating of Green was recorded.
The ONR Nominated Site Inspectors for Heysham 1 and Heysham 2 both attended the LCLC where both stations presented an update on their safety performance since the last meeting to the local community. ONR presented the quarterly report for both stations and no questions were raised on the report by the LCLC members.
The intervention was performed in line with ONR's guidance requirements (as described in our technical inspection guides) in the areas inspected.
From the evidence gathered during these inspections, it was judged that there were no matters that have the potential to impact significantly on nuclear safety.
At present, no additional regulatory action is needed over and above the planned interventions of Heysham 1 power station as set out in the Integrated Intervention Strategy, which will continue as planned.