Office for Nuclear Regulation

Hinkley Point C – Inspection ID: 52645

Date(s) of inspection

  • October 2023

Executive summary

Aim of inspection

The aim of the inspection was to inspect the implementation of NNB Generation Company (HPC) Ltd’s (NNB GenCo) arrangements for compliance with Licence Condition (LC) 19 – construction or installation of new plant, in relation to civil engineering construction assurance. LC19 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 inspection aimed to obtain evidence in relation to the adequacy of the implementation of NNB GenCo’s arrangements for the control of the construction of nuclear safety related civil structures. The particular focus of the inspection was on the adequacy of the site surveillance activities 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 arrangements for the surveillance of civil engineering works associated with the nuclear island and heat sink structures, were risk informed, targeted and under implementation. Furthermore, the civil engineering contractor’s quality control arrangements in relation to construction of buildings were under implementation and were aligned with relevant good practice.

This inspection highlighted no significant regulatory issues. However, NNB GenCo recognised that action is required to reduce overall rates of non-conformance in reinforced concrete construction, and an improvement programme has been developed and is being progressively implemented.

Actions raised in relation to requests for further evidence have all been completed.

Progress with the improvement initiatives outlined and residual matters will be followed up at routine level 4 meetings.


On the basis of the evidence sampled, I judge that NNB GenCo has implemented corporate arrangements in compliance with LC19 (construction or installation of new plant). In relation to the specific areas sampled, I judge that NNB GenCo is taking a risk informed and targeted approach to site surveillance activities and is proactively seeking to drive improvements in construction quality compliance. I also judge that the civil engineering contractor’s quality control arrangements in relation to construction of buildings significant to nuclear safety are being implemented and are aligned with relevant good practice.

Overall, I was satisfied with the adequacy of NNB GenCo’s ongoing arrangements associated with surveillance of civil engineering construction works. On the basis of the evidence sampled, and in recognition of progress to date, I was satisfied that the arrangements in place comply with LC19.

Upon consideration of the ONR guidance in relation to inspection ratings, I judge that a rating of Green (no formal action) is appropriate.