Executive summary
Date(s) of inspection: April 2024
Aim of inspection
The aim of the inspection was to inspect NNB Generation Company (HPC) Ltd's (NNB GenCo) arrangements for compliance with Licence Condition 19 (LC 19), construction or installation of new plant, in relation to civil engineering construction assurance. LC 19 requires that where the licensee proposes to construct or install any new plant, which may affect safety, the licensee makes and implements adequate arrangements to control the construction or installation.
The objective of the inspection was to obtain evidence in relation to the adequacy of NNB GenCo’s arrangements for the control of the post-tensioning of the unit 1 inner containment reinforced concrete wall. The particular focus of the inspection was on the implementation of arrangements to ensure conformant construction of civil engineering elements, in accordance with the design intent and safety case.
Subject(s) of inspection
- LC19 - Construction or installation of new plant - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
The evidence sampled provided confidence that the implementation of arrangements for construction of the unit 1 inner containment phase 1 post-tensioning were adequately controlled. Based on sampling of the initial trial installation of four permanent tendons, construction of the post-tensioning system was found to align with the design intent and the safety case and provided confidence as to the readiness to commence phase 1 activities.
This inspection highlighted no significant regulatory issues. A small number of observations were made and some queries were raised, which will be followed up as part of routine regulatory business.
On the basis of the evidence sampled, and in recognition of progress to date, I was satisfied that the arrangements in place comply with LC 19.
Conclusion
On the basis of the evidence sampled, I judge that NNB GenCo has adequate arrangements under LC 19 (construction or installation of new plant) for the installation of phase 1 of the post-tensioning system on the unit 1 inner containment structure and that those arrangements are under implementation.
Upon consideration of the ONR guidance in relation to inspection ratings, I judge that a rating of Green (no formal action) is appropriate.