- Site: Hinkley Point C
- IR number: 20-014
- Date: September 2020
- LC numbers: 19
Executive summary
Purpose of Intervention
This intervention was conducted remotely with staff from NNB Generation Company (HPC) Ltd (hereafter referred to as NNB GenCo). It was undertaken as part of the ONR intervention plan, HPC Project Intervention Plan beyond J0.
Interventions Carried Out by ONR
I conducted a Licence Condition (LC) 14 (Safety Documentation) compliance inspection targeted on the management of commitments arising from ongoing safety studies / safety case documentation for capture in the future safety case and/or operational instructions. The intervention focused on the following purposes:
- understand the different approaches to managing commitments
- sample implementation of the operational commitments database
- consider the overall adequacy of management of commitments
I assessed NNB GenCo’s LC arrangements and implementation of those arrangements against relevant good practice, which included the following ONR regulatory guidance:
- LC 14 Technical Inspection Guide
- NS-PER-GD-001 Revision 4 - The Purpose and Use of Permissioning
- NS-TAST-GD-051 (Rev 6) - The purpose, scope and content of nuclear safety cases
Key Findings, Inspector's Opinions and Reasons for Judgements Made
I found that NNB GenCo has made significant progress in developing robust processes for the management of commitments arising from previous and ongoing safety studies for capture in future safety cases and operational instructions. In particular, a pre-operational commitments database has been developed that will: ensure that all Operational Commitments are incorporated into the correct operational documentation; ensure that once incorporated the requirements and rationale are not lost in future updates; will maintain an auditable trail of the resolution of these commitments and will provide a tool to assist with any future modifications by clearly capturing the original design intent.
A new Safety Report Development Tracker tool has been developed post production of PCSR3 and is being used to support management of safety report production. I sampled the Safety Report Development Tracker and found that a number of topics that had been pre-selected were present and that other commitments sampled had been adequately captured, i.e. clear definition of commitment, clear timescales for delivery and tracking of progress and clear requirements to be met for closure. In my opinion, there is a clear mechanism for ensuring that the Golden Thread is maintained via the link from the Safety Report Development Tracker to System/ Topic Route Maps (S/TRMs).
During my inspection I identified one minor shortfall and a level 4 regulatory issue will be raised to ensure the mitigation of this shortfall in a timely manner. The shortfall relates to NNB GenCo being able to demonstrate the basis for their confidence that all operational commitments, including historic, are captured from the full suite of safety case documentation and relevant staff are aware of operational commitment requirements.
I judged that, on the evidence sampled, NNB GenCo has adequately implemented arrangements for capturing, controlling, and managing commitments that have been made within safety cases and safety studies in accordance with Relevant Good Practice as defined in ONR regulatory guidance. It is my opinion that an inspection rating of Green (no formal action) is merited.
Conclusion of Intervention
Overall, based upon the judgements described above, I have concluded that an inspection rating of ‘GREEN’ is appropriate for LC14 Safety Documentation.
An appropriate regulatory issue will be raised to address the minor shortfall identified during this intervention.