Executive summary
Date(s) of inspection
- July 2026
Aim of inspection
The aim of this inspection was to gain regulatory confidence that Heysham 2 adequately implemented the C&I aspects of modification EC 374528 (NP/SC 7835), in compliance with existing arrangements in place, under LC 21, LC 22 and LC 28.
It should be noted that the sample verification of the adequacy of installation and commissioning against LC 21 and LC 22 arrangements covered activities within the scope of the site testing and installation instructions, as per document STI8721 Issue B.
This inspection was part of activities to inform ONR’s decision on whether to lift the hold point on the Leak Termination System at HYB, as documented within PR-01718, with permissioning carried out under derived powers.
I targeted the installation and commissioning phases, as these incur the highest risk during the modification implementation and would provide greatest confidence of EDF’s management of the process.
By inspecting the modification during the installation and commissioning phases, I was able to gain sufficient confidence that Heysham 2 was adequately implementing its C&I modification arrangements and applying relevant good practice.
Subject(s) of inspection
- LC 21 - Commissioning - Rating: GREEN
- LC 22 - Modification or experiment on existing plant - Rating: GREEN
- LC 28 - Examination, inspection, maintenance and testing - Rating: GREEN
Key findings, inspector's opinions and reasons for judgement made
During this inspection I sampled, supported by my colleagues, Control and Instrumentation (C&I) aspects of the Leak Termination System modification project being implemented at Heysham 2.
We undertook a plant walkdown of the Leak Termination System modifications, including newly installed logic panels, safety cubicle modifications, boiler analogue control cubicle modifications and control room alarm fascia changes. Overall, we found the equipment to be in good physical condition and observed evidence of good construction and installation practices.
We observed evidence of good practice in proactive management of equipment obsolescence through planned upgrades to safety-related equipment, safety system re-validation, and training arrangements for operations staff.
We held discussions with engineering, operations and management personnel who demonstrated a good understanding of the modification, its nuclear safety function and the associated operational impacts and risks.
We sampled project governance, installation and commissioning, quality assurance, management of non-conformances, spares management and training arrangements. We obtained sufficient regulatory confidence that the risks associated with the integration of the Leak Termination System were being adequately managed.
However, we also identified a small number of minor shortfalls. These included housekeeping, cable installation, age-related degradation, documentation and quality assurance. Whilst we consider that none of these findings posed an immediate or significant risk to nuclear safety, we provided regulatory advice as appropriate. We verbally communicated the advice during the hot wash-up and consider that HYB responded adequately. Post-inspection I also fed back the inspection outcome and regulatory advice to the Nominated Site Inspector.
Conclusion
Based on our sampled inspection of the C&I aspects of the Leak Termination System modification, I have assigned an inspection rating of Green to LC 21 ‘Commissioning’, LC 22 ‘Modification or experiment on existing plant’ and LC 28 ‘Examination, inspection, maintenance and testing’.
Based on the areas sampled during our inspection, I did not identify any significant issues in relation to the C&I equipment during this inspection that could prevent ONR from supporting a release of hold point PR-01718.