Executive summary
Date(s) of inspection
- July 2026
Aim of inspection
The purpose of this inspection is to assess AWE’s LC20 compliance at **2* for the control of modifications to the design of plant which may affect safety during the period of construction.
The inspection will consider:
- The adequacy of AWE's current arrangements for control of modifications at **2*.
- The adequacy of implementation of these arrangements.
Subject(s) of inspection
- LC20 - Modification to design of plant under construction - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
This inspection judged the adequacy of AWE’s LC 20 compliance for the control of modifications to the design of plant which may affect safety during the period of construction at **2*.
Against ONR's Technical Inspection Guide for Licence Condition 20 (NS-INSP-GD-020) we sampled:
- The adequacy of AWE's current arrangements for control of modifications at **2*.
- The adequacy of implementation of these arrangements.
In advance of the inspection, AWE provided its arrangements for the control of modifications. Using these we inspected the practical implementation of AWE's control of modifications at **2* with a range of relevant AWE staff. This included sampling how recent modifications were recorded and justified in AWE's documentation. We found that within the areas sampled:
- AWE adequately manages and governs modifications to the design of plant which may affect safety using defined processes at **2*.
- AWE’s arrangements adequately prevent safety-significant design changes being made without appropriate control and approval.
- AWE adequately controls that modifications are reviewed and approved by suitably authorised, qualified and experienced personnel before implementation, including where aspects of modification design or assessment are provided by the supply chain.
- AWE's LC 20 arrangements adequately allow for classification of modifications by safety significance and this allows a graded approach to control and justification to be consistently applied.
- AWE adequately demonstrated that suitable safety documentation is in place to justify modifications and that LC 20 arrangements make adequate provision for submission of modifications to ONR/DNSR where appropriate.
- AWE's LC 20 arrangements and their implementation adequately allow for genuine design changes and normal design development activities to be distinguished and handled appropriately.
- AWE developed confidence that there is adequate planning for how control of modifications will be handled in the future, including once the plant is no longer under construction.
As such, against ONR’s General Inspection Guide (ONR-INSP-GD-064), we rated LC 20 - Green.
Conclusion
We judged that the inspection scope was fully achieved and that AWE demonstrated that adequate arrangements were in place and implemented for the control of modification of plant under construction at **2*.
Therefore the inspection rating (LC 20) was GREEN.