Executive summary
Date(s) of inspection:
- March 2025
Aim of inspection
The aim of this inspection was to gain assurance the Licensee and relevant contractors e.g. Wincanton have developed, and are implementing, on and off-site quarantine arrangements in a suitable and sufficient manner, and these arrangements are taking account of the response to RI-11717 (Application of Quarantine Arrangements).
Subject(s) of inspection
- LC6 - Documents, records, authorities and certificates - Rating: AMBER
- LC17 - Management systems - Rating: AMBER
- LC19 - Construction or installation of new plant - Rating: AMBER
Key findings, inspector's opinions and reasons for judgement made
The inspection findings were as follows:
- The arrangements for on-site quarantine have continued to evolve since they were identified as requiring improvement in Regulatory Issue (RI) -11717 (Application of Quarantine Arrangements). There is now evidence of greater control of on-site quarantined items but further work is required to ensure the arrangements are fully developed and deployed on-site.
- In parallel, NNB GenCo (HPC) have continued to work with Wincanton (a specialist storage contractor) to finalise the revised quarantine arrangements for off-site locations. There is now evidence of enhanced controls in certain areas but further improvements are required to ensure the arrangements are consistent and scalable across all off-site locations, and have broad consistency with the on-site arrangements.
- In developing the finalised arrangements, NNB GenCo (HPC) and Wincanton are considering the simplification and the clarification of their processes and arrangements which interface with the revised quarantine arrangements e.g. soft-locks.
- To facilitate the revised arrangements, work is ongoing to implement or enhance Information Technology (IT) systems and reporting tools e.g. PowerBI.
- The communication of the revised arrangements to NNB GenCo (HPC) staff, Wincanton and Design, Manufacture Installation and Commissioning (DMIC) contractors will need effective planning and delivery.
Conclusion
NNB GenCo (HPC) and Wincanton have continued to review and revise their on and off-site quarantine arrangements in response to RI-11717 and findings from previous ONR inspections (IR-53080 &IR-53073). In doing so, there has been an improvement in the application of the arrangements. However, during the inspection areas for improvement remain in both the on and off-site quarantine arrangements. NNB GenCo (HPC) and Wincanton recognise further work is required to improve the quarantine arrangements in these area, and were able to demonstrate the work required deliver the improvements and a programme for completion of the work.
The revised approach appears to be adequate although the underpinning details require further development and subsequent communication. On this basis, an AMBER rating was assigned to the inspection and ONR will maintain oversight of the ongoing work via RI-11717.