- Site: Sellafield
- IR number: 21-058
- Date: July 2021
- LC numbers: 28
Executive summary
Purpose of Intervention
In 2021-22, the Office for Nuclear Regulation (ONR) is carrying out a Chief Nuclear Inspector’s (CNI) themed inspection on the management of ageing assets. This comprises a series of inspections across nuclear site licensees, the purpose of which is to seek evidence of sustainable programmes for the management of ageing assets against four themes: strategy, organisational capability, obsolescence and ongoing investment. Prior to the inspections, each licensee was requested to complete a self-assessment to provide an understanding of the licensee’s arrangements and how they align with the themes for the inspection and supporting criteria. These self-assessments form the basis for the site-based inspections which test the licensee’s compliance with the arrangements and relevant good practice.
Interventions Carried Out by ONR
On 28 and 29 July 2021, ONR carried out a themed inspection on the management of ageing assets at Sellafield Ltd’s Thermal Oxide Reprocessing Plant (THORP) Receipt and Storage facility. The focus of the inspection was on Theme 3 (obsolescence), specifically, covering cooling water systems, ventilation systems and security systems within the THORP Receipt and Storage facility. The inspection comprised discussions with Sellafield Ltd staff, a walkdown of the facility and review of plant records and other documentation. The inspection was undertaken by specialist inspectors in Control and Instrumentation, Civil Nuclear Security and Mechanical Engineering, together with the Site Inspector for Oxide Fuel Storage and a representative of the Chief Nuclear Inspector’s office. The inspection was carried out against Licence Condition 28 (Examination, inspection, maintenance and testing). The inspection utilised relevant ONR guidance, including NS-INSP-GD-028 (LC28 – Examination, inspection, maintenance and testing) and NS-INSP-GD-098 (Asset Management).
The Civil Nuclear Security inspector recorded their findings from the inspection in a separate Intervention Record.
Explanation of Judgement if Safety System Not Judged to be Adequate
This was not a system-based inspection, and therefore no judgement has been made of the adequacy of implementation of any part of the safety case.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
During the inspection, I examined Sellafield Ltd’s arrangements for identifying and managing obsolescence issues. This covered both proactive and reactive approaches. I was satisfied that Sellafield Ltd has adequate arrangements for managing obsolescence and these are being implemented effectively within the THORP Receipt and Storage facility.
Sellafield Ltd has identified an intention to become more proactive in its approach to obsolescence management. Progress in this area has been constrained by resource limitations, as well as some technical issues with the IT systems used. I provided regulatory advice to Sellafield Ltd to ensure that adequate resource is assigned to this work.
I considered the training provided by Sellafield Ltd on ageing management as part of its broader system engineering training. I judged this was adequate.
Sellafield Ltd was able to demonstrate via the maintenance items sampled that it was conducting maintenance in accordance with schemes laid down in writing and within the intervals specified within the plant maintenance schedule. A sample of the training records of the personnel undertaking the maintenance identified that the individuals were suitably qualified and experienced, however, Sellafield Ltd was unable to demonstrate, in all cases, that personnel controlling and supervising maintenance were appointed under LC28. A regulatory issue has been raised to address this.
Conclusion of Intervention
I judged from the evidence sampled that Sellafield Ltd is effectively managing ageing assets in Thorp Receipt and Storage from the point of view of obsolescence. I have therefore assigned an inspection rating of Green (no formal action) against Licence Condition 28.
The Civil Nuclear Security inspector identified shortfalls in the implementation of Sellafield Ltd’s ageing management arrangements to the security systems in Thorp Receipt and Storage. The security specialist therefore assigned an Amber rating (seek improvement).
I identified a minor shortfall in relation to appointment of persons to control and supervise maintenance within Thorp Receipt and Storage. I have raised a Level 4 (lowest level) regulatory issue for Sellafield Ltd to address this.