- Site: Torness
- IR number: 22-045
- Date: June 2022
- LC numbers: 22, 28
Purpose of Intervention
This Intervention Record covers the Control and Instrumentation (C&I) inspection performed as part of an ONR Operating Facilities Division (OFD) intervention applicable to EDF Nuclear Generation Ltd (EDF NGL) during the Reactor 2 (R2) Statutory Outage 2022 at Torness Power Station. The main focus of this inspection was to verify that relevant work activities have been carried out in relation to C&I equipment and systems important to safety in order to confirm that it remains fit for its intended purpose at Torness. The intervention is intended to provide a contribution towards ONR’s regulatory decision as to whether a Consent, in accordance with LC30 (periodic shutdown), should be issued to allow Torness to return to normal operating service.
Interventions Carried Out by ONR
This inspection was undertaken in support of ONR’s 2022/23 statutory outage inspection programme. The outcome of this inspection, which included a review of progress made in various work items and projects associated with C&I equipment and systems important to safety at Torness, covered EDF NGL’s arrangements under Licence Conditions LC22 (modification or experiment on existing plant), and LC28 (examination, inspection, maintenance and testing).
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
Key Findings, Inspector’s Opinions and Reasons for Judgements Made
At the last outage inspection at Tormess on Reactor 1 (R1), the Station was being challenged by degraded or failed neutron flux detectors. It was noteworthy that, at this inspection, the position in regard the health of neutron flux detectors, across both reactors, has greatly improved and the plan going forward is positive. We consider this a significant improvement.
During our inspection we found examples of good ageing and obsolescence forward planning and management. We also found the plant areas and equipment cubicles inspected to be clean, tidy, and free from foreign materials, which demonstrated that good housekeeping practices were being followed. The staff we talked to also appeared to have a good level of knowledge of the systems and equipment they were responsible for. However, we did note an area for improvement in regard clarity of some maintenance instructions associated with the Chloride Ingress Protection.
Our inspection found that the commitments made in the Torness R2 Outage Intentions Document for C&I equipment and systems important to nuclear safety have been satisfied for those elements of work complete at the time of the inspection. Our inspection of the work activities covered during this intervention has generally found that the workmanship applied was adequate and consistent with the standards expected from C&I suitably qualified and experienced persons (SQEP).
During our inspection we reviewed the implementation of some Engineering Changes that had been identified in EDF NGL’s Outage Intentions Document. These were, in the main, associated with the Quadrant trip hardening project and phased reinforcement of reactor protection equipment. However, there were some additional modifications being undertaken to the Torness on-line computer system over and above the quadrant hardening related modifications. I considered the modifications and testing had been satisfactorily completed with the documentation and processes appropriately managed and signed off.
Based on our sample inspection of the C&I aspects of the Torness R2 2022 statutory outage I have assigned an intervention rating of Green to LC22 and LC28 compliance.
Conclusion of Intervention
From the evidence gathered during our C&I-based intervention, we have not identified any other significant issues in relation to the C&I equipment and systems that should prevent ONR from issuing a Consent under LC30 to allow Torness R2 to restart following the statutory outage.
On the basis of our inspection of C&I aspects of the Torness R2 2022 statutory outage it is recommended that support be given for a Consent to allow Torness to return to normal operating service following successful completion of the planned maintenance activities in accordance with LC30.