Executive summary
Date(s) of inspection: March 2024
Aim of inspection
This themed inspection assessed EDF NGL’s management of ageing civil engineering building structures (including weather envelope) and infrastructure at Torness nuclear power station. The asset care of the civil engineering systems may have potentially significant nuclear safety consequences if risks are not adequately controlled. ONR examined EDF NGL’s compliance with arrangements made under Licence Condition 28 (LC28) from the perspective of controlling risks from external hazards. This inspection scope incorporates learning from previous interventions, including at Dungeness B, Heysham A and B, and Sizewell B.
This was a planned intervention in accordance with ONR’s Operating Reactors sub-division Integrated Intervention Strategy (IIS) for 2023/24. The intervention is one of a series of inspections on management of ageing civil engineering structures and infrastructure across EDF NGL stations. This suite of themed inspections is risk-informed and intelligence led, including following up the licensee's response to an ONR enforcement letter. The enforcement letter relates to shortfalls in EDF NGL's company civil engineering LC28 arrangements and the implementation of these arrangements at stations. A similar topic was the focus of the EDF NGL Chief Civil Engineer Tour in 2022/23 alongside the recent EDF NGL fleet-wide cladding, glazing and louver repair campaign. The ONR Chief Nuclear Inspector (CNI) focused a recent themed inspection on the management of ageing facilities including the lower risk and hazards posed by reactors that have been defueled. This inspection has similarly reviewed site arrangements in place to facilitate the planned changes in risk in the coming years.
Subject(s) of inspection
- LC28 - Examination, inspection, maintenance and testing - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
The inspection included:
- Background and progress since ONR's enforcement letter relating to EDF NGL's LC28 arrangements for civil structures.
- Overview of safety cases relevant to the inspection theme.
- Review of the licensee’s progress with addressing findings raised by the third Periodic Safety Review (PSR3) for Torness in 2019.
- Management of defects identified from the last LC28 civil structures inspection.
- Discussions around asset care arrangements including LC28 defect management and assets that provide the function of weather protection.
The inspection included plant walkdowns of:
- Reactor buildings.
- Fuel pond (internals).
- Cooling water system/pump house.
- Externals of ancillary buildings.
- Sea defence wall.
The evidence to inform our judgement was gathered from a sample of the following documents and records, some shared via screen:
- Inspection guidance documents including EDF NGL corporate specifications.
- LC28 inspection reports, including check sheets appended to the reports.
- LC28 defect databases located on the EDF NGL Civil Engineering Microsoft Teams channel.
- Observations made during the plant walkdown.
- Records on EDF NGL's work management system, including work requests and work order cards.
We found that the licensee is making improvements in civil engineering LC28 defect management, demonstrating that changes had been implemented at Torness since our fleetwide enforcement letter was issued. The aspects of work discussed during intervention have indicated that the ongoing improvements will benefit the civils system information management.
During the intervention we noted the ongoing proactive approach taken by the civil systems engineer and their team. This has been made possible in part by increased resource to support the civils works at the station including an embedded contractor. We also observed closer engagement with the central Civil Engineering team. The benefit of this additional support to relevant works, such as that undertaken on cladding, louvres and glazing and other LC28 defect asset management were demonstrated in that there were notably few civil engineering defects following a storm earlier in 2024. This shows that maintenance campaigns can effectively support civil engineering work on site.
Conclusion
LC28 requires the licensee to make and implement adequate arrangements for the regular and systematic examination, inspection, maintenance and testing of all plant which may affect safety, which includes relevant civil engineering structures.On the basis of evidence sampled for LC28 at the time of this inspection a Green rating (No formal action) is awarded. No regulatory issues have been raised. EDF NGL's ongoing improvements to their LC28 arrangements for civil structures are covered by the existing corporate fleet-wide Regulatory Issue RI-11478. EDF NGL's continued progress and delivery of the LC28 improvement plan will be followed up by ONR as normal regulatory business.