The purpose of this intervention was to undertake a licence condition (LC) compliance inspection at EdF Energy Nuclear Generation Limited (NGL) Heyham1 Power Station, in line with the inspection programme contained in the Heysham 1 integrated intervention strategy (IIS) for 2016/17. Specifically, this was part of a fleet-wide, corporate LC22 inspection.
As part of this intervention, we inspected NGL's LC22 Modification or Experiment on Existing Plant arrangements, in accordance with ONR guide NS-INSP-GD-022 Revision 3. We focused on configuration control of plant in the process of being modified. The intervention was based upon a review of associated procedures and interrogation of various lists including Category 1, 2 and 3 lists of modifications, Safety Case Anomalies, Defeat of Interlocks and Long Term Out of Service Plant and interviews with relevant station staff.
No safety system inspection was undertaken, hence this is not applicable.
From our inspection of the arrangements for the control of a modifications, focusing on configuration control of plant being modified, we noted sufficient checks and balances within the procedures, electronic modification form and Asset Management System to allow for adequate configuration control.
We sampled how all the open modifications on the station are controlled. This showed that a number of KPIs are monitored, and review meetings are conducted. We noted that staff recognised the impact of KPIs on human behaviours. We did note that there were a number of long standing modifications which appeared to be legacy modifications. These made identifying the real longer term active modifications more difficult. One minor, specific issue has been raised against the station to confirm that long standing modifications still meet their safety justifications. We also noted that several responsible engineers (REs) were responsible for a large number of modifications. However, we did recognise the improving KPI trends and reducing numbers of open modifications.
There was a limited number of long term out of service plant items, which indicated that the isolations were under control.
The list of Safety Case Anomalies showed that there was a limited number of Interim Justification for Continued Operation (IJCO) documents, with reasonable durations. We judged that they were under control.
The list of Fuel Route Interlock Defeats demonstrated that defeat of interlocks was currently under control.
Based on our sampled inspection, we judged that the implementation of the arrangements for LC22 reflect good practice and have rated this intervention as Green.
Overall, we consider that the arrangements and their associated implementation for LC22 from the sampling undertaken met with legal requirements; we have therefore rated this inspection as Green.
There are no findings from this inspection that could significantly undermine nuclear safety nor require a change to the planned interventions and inspections of Heysham 1.