Executive summary
Date(s) of inspection: September 2024
Aim of inspection
The aim of this inspection is to seek assurance that NRS Wylfa's arrangements for compliance with LC34 (Leakage and escape of radioactive material and radioactive waste) are adequate, and have been adequately implemented.
Subject(s) of inspection
- LC34 - Leakage and escape of radioactive material and radioactive waste - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
I carried out a LC34 compliance inspection at the NRS Ltd Wylfa site. LC34 concerns the control and containment of radioactive materials and radioactive wastes so far as is reasonably practicable to prevent their leakage or escape (including unintended release to land or groundwater), and the detection, notification, recording, investigation and reporting of any leakage or escape that occurs.. I utilised ONR guidance NS-INSP-GD-034 Revision 6 during the inspection. I reviewed the arrangements for this LC and their implementation, focussing on the DCICs (ductile cast iron containers) stored in DSC4 (dry store cell 4), and found them to be adequate. However, I was unable to find evidence that NRS had adequately considered the potential impact of the high-humidity storage conditions on the eventual acceptance of the DCICs into a GDF. I also found that the description of the storage conditions and their consideration within the relevant documentation, including the safety case, were not sufficiently clear, and have therefore raised a L4 issue.
Conclusion
I considered applicable legislation and relevant good practices including, but not limited to,
- Licence Condition 34(1) and (2)
- NS-INSP-GD-034 Issue 6 Licence Condition 34 Leakage and Escape of Radioactive Material and Radioactive Waste.
Based on the evidence sampled during this inspection, I judged there were no significant compliance shortfalls in NRS's arrangements, and therefore I assigned a GREEN inspection rating.
I also raised a L4 Issue related to the high humidity of the storage conditions of the DCICs (RI-12221).