Date(s) of inspection:
- December 2022
Aim of inspection
The aim of the inspection was to gain confidence that the licensee, NNB Generation Company (HPC) Ltd (NNB GenCo), had adequate arrangements in place for compliance with Licence Condition (LC) 19, in relation to:
- pressure regulations compliance for nuclear pressure systems (NPS);
- effective control over its supply chain for NPS, considering implementation of the Pressure Systems Safety Regulations 2000 (PSSR)-safety case policy (PSCP);
- promoting and implementing the PSCP in the supply chain during manufacturing;
- adequacy of oversight arrangements during transport, storage and site installation; and
- inclusion of operational experience (OPEX) from the supply chain to inform appropriate improvements to the PSCP policy.
Subject(s) of inspection
- LC19 – Construction or installation of new plant – Rating: Green
Key findings, inspector’s opinions and reasons for judgement made
I checked the more theoretical aspects of the PSCP at an earlier inspection. This inspection tested the efficacy of the licensee’s arrangements in implementing all aspects of that policy using a specific component (the containment heat removal system (EVU)).
The sampled evidence included inter alia design, material procurement, fabrication, manufacturing, testing, inspection, installation, hydrotest etc. Considering the difficulties with complex manufacturing in this project, I particularly sampled the non-conformance reports (NCRs) raised during manufacturing to check if the licensee had good visibility of the issues and that the licensee has demonstrable oversight on the activities undertaken by the manufacturer to mitigate the shortfalls and eventually demonstrate compliance. I also sampled activities of the external inspection agency (EIA) appointed by the licensee to support the Competent Person Organisation’s (CPO) decision on demonstration of compliance.
I was satisfied that the licensee has adequately demonstrated the effectiveness of the PSCP for the EVU pipework and that its CPO is demonstrably capable to undertake activities as stated in the PSCP. I gained confidence that the CPO arrangements are robust in reviewing the supporting evidence and their decision-making process involves significant scrutiny to ensure that the evidence is adequate.
Based on the evidence sampled and clarifications obtained during the inspection, I am content that the licensee has satisfactorily demonstrated implementation of the PSCP along with the associated new governance arrangements, the CPO. I judge that the processes along with the governance arrangements are sufficiently robust to demonstrate compliance with statutory regulations as well as relevant safety case requirements.
Whilst some residual actions have been raised as a result of this inspection, I do not judge these to be significant enough to warrant a regulatory issue. I plan to deal with these via routine regulatory engagements. Furthermore, I will continue to monitor the use of the PSCP via another pressurised system in the future, to check and ensure if the process has remained sufficiently robust and effective.
I rated this inspection GREEN as relevant good practice with CPO and its governance arrangements were demonstrably met, legal duties were judged to be complied with and although several actions have been raised, no significant shortfalls were identified.