Office for Nuclear Regulation

CD18 Unit 1 Civil Engineering Construction Compliance (Level 3)

Executive summary

Purpose of Intervention

In accordance with the Office for Nuclear Regulation (ONR) Hinkley Point C Construction Inspection Plan, ONR performs a series of planned compliance inspections of identified licence conditions. This is to ensure that the licensee, NNB Generation Company (HPC) Ltd (NNB GenCo), is adequately developing and implementing its licence compliance arrangements in a manner commensurate with the stage of the project under consideration.

This intervention was an inspection carried out to assess the licensee’s compliance with licence condition 19 (LC19) Construction or Installation of New Plant. 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.

This intervention was led by ONR civil engineering construction assurance (CECA) and sought to assess the licensee’s application of relevant good practice (RGP) in the area of ensuring compliance with the construction specification for the nuclear island structures of Unit 1.

Due to Covid-19 this intervention was undertaken remotely using Skype in conjunction with e-mail correspondence.

Purpose of Intervention

This intervention sought to assess the licensee’s application of relevant good practice (RGP) principally in the area of ensuring compliance with the construction specification for the nuclear island structures of Unit 1. Some sampling was also taken of the Unit 2 nuclear island.

The intervention was a formally rated intervention done principally against the requirements of LC19.

The principal aims of the intervention can be summarised as follows:

Explanation of Judgement if Safety System Not Judged to be Adequate

This section is not applicable as this was not a safety system inspection.

Key Findings, Inspector's Opinions and Reasons for Judgements Made

The intervention was well managed and NNBGenCo planned for attendance by the appropriate personnel. The evidence submitted was of good quality and submitted in a timely fashion that has allowed me to form a regulatory judgement.

Overall, I was satisfied with the licensee’s current arrangements to assure conformant construction of the Unit 1 civil engineering works. This topic is one of continued regulatory interest and it is acknowledged that significant challenges exist in establishing and implementing practical arrangements to assure conformant construction on any major civil engineering site; particularly where multiple contractual interfaces exist and where design release is overlapping with construction. To this end, I have made a few forward-looking observations within this intervention and these have been acknowledged by the licensee. Perhaps the most notable challenge, currently evident from this intervention, is that of practical implementation of the licensee’s own non-conformance report (NCR) process in the context of the typical spectrum of civil engineering non-conformances arising at site. This is particularly evident where the NCR process is being used heavily to control on-going work leading to pouring of concrete. This challenge is openly acknowledged by the licensee and I see no need at this particular juncture to raise a formal regulatory issue on this matter following this intervention.

Ten actions were agreed from this intervention, which will be followed-up through the future regular interactions with the licensee. The actions do not affect my assessment rating.

Conclusion of Intervention

On the basis of the current evidence sampled, I was broadly satisfied that the licensee’s arrangements met relevant good practice. I therefore judge that a rating of GREEN (No formal action) is appropriate against this LC19 intervention.