- Site: Torness
- IR number: 21-028
- Date: June 2021
- LC numbers: 24, 26, 28
Executive summary
Purpose of Intervention
The purpose of this intervention was to conduct a Procedural Quality Use and Adherence and Configuration Control themed inspection of EDF Energy Nuclear Generation Ltd’s (NGL) at Torness (TOR) Power Station.
This intervention was undertaken as part of a series of planned interventions that are listed in the Torness Integrated Intervention Strategy 2021/2022.
Interventions Carried Out by ONR
The intervention was carried out by ONR’s Nominated Site Inspector for Torness and a Human Factors Specialist Inspector over the period 8th to 10th June 2021 and was rated against Licence Condition 24 (Operating Instructions), Licence Condition 26 (Control and Supervision of Operations) and Licence Condition 28 (Examination, Inspection, Maintenance and Testing).
The Procedural Quality Use and Adherence and Configuration Control Themed Inspection was conducted with the following areas sampled:
- Emergency Boiler Feed Feedwater Supply Isolation Valves (WF/200) MS testing (reactor operations)
- Configuration of the RSW pump interconnector isolation valves (RSW/11) and half-unit manifold RSW crossover isolation valves (RSW/40) prior to start-up of the reactor (reactor operations)
- Visual Checks of New Elements and Proof Pressure Test of the graphite sleeve (fuel route operations)
The focus of the inspection was to establish if the licensee’s arrangements are adequately implemented; the inspection focused on the adequacy of operating instructions and associated documentation, task handovers, pre- and post-job briefing, and the level of supervision required to carry out activities safely.
A plant walkdown was conducted with an experienced operator and the inspection included discussions with various responsible members of EDF NGL staff.
The intervention was performed in line with ONR's guidance requirements (as described in our technical inspection guides) in the areas inspected.
Explanation of Judgement if Safety System Not Judged to be Adequate
Not applicable, no system-based inspection was undertaken.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
Interventions ratings of Green were assigned for LC24 and LC26. An intervention rating of Amber was assigned to LC28, relating to shortfalls in ensuring a full and accurate report of examination, inspection, maintenance and test identified during the inspection sample. The main shortfall against LC28(9) was:
- From the sample of documents reviewed during the inspection, there are potential gaps in the recording of the Independent Verification of plant maintenance activities.
Whilst this shortfall in relation to LC 28(9) may not in itself be sufficient to rate the inspection findings as amber, additional issues were raised which also have relevance for LC28, particularly around defect tolerance across the plant and equipment sampled, which collectively I judge to be of significance. These include:
- There were two identified examples of Torness not complying with internal processes relating to control of procedures and work briefings. The extent to which the processes are not applied at Torness is unclear, however the lack of knowledge and understanding of these processes is a potential concern.
- There was an indication of a tolerance of degraded plant condition during ONR’s plant walkdown, through discussions with station personnel, review of issues raised in system engineer walkdown reports and a sample of current defect tags.
- A review of a sample of test records identified missing information and other amendments made without following the correct process.
- The operator escorting ONR during the walkdowns was unable to clearly articulate the steps within the Reference Use procedure for a sampled task. This raises a question as to the SQEPness of the individual and whether the procedure was used in line with “Reference Use” designation as per the NGL processes.
Conclusion of Intervention
Intervention ratings of Green were assigned for LC24 and LC26 and Amber for LC28, relating to shortfalls in the retention and development of full maintenance records. A number of findings were raised which will form the basis of a level 3 Regulatory Issue, allowing the resolution of the identified shortfalls to be tracked to completion. Several observations were also raised which will be followed up on through Torness normal business. There were no findings from this inspection that could significantly undermine nuclear safety.