Office for Nuclear Regulation

Pile Fuel Cladding Silo on Sellafield Ltd.’s nuclear licensed site at Sellafield, Cumbria

Executive summary

Purpose of Intervention

In accordance with the Office for Nuclear Regulation’s (ONR’s) Sellafield Strategy, each year ONR performs a series of planned compliance inspections of selected licence conditions, targeted at those facilities with significant importance to nuclear safety.

This record describes the outcome from a planned compliance inspection at the Pile Fuel Cladding Silo (PFCS) facility on the Sellafield Site. This intervention targeted PFCS as it is a high hazard facility and its continued safe operation during the COVID-19 pandemic is key to continued nuclear safety of the Sellafield site. The purpose of the inspection was to confirm Sellafield Limited’s (SL) compliance with its corporate arrangements for Licence Conditions (LC): 10 (Training); 11 (Emergency arrangements); 12 (Duly authorised and other suitably qualified and experienced persons (SQEP)); 26 (Control and supervision of operations) (not rated); and, 36 (Organisational capability) (not rated).

The inspection was undertaken remotely noting the limitations currently in place as a result of the coronavirus (COVID-19) pandemic. The inspection has been carried out in line with the ONR Sellafield Decommissioning, Fuel & Waste Division’s regulatory approach to the coronavirus situation.

In response to the pandemic, SL has recognised that its existing corporate compliance arrangements should remain unchanged and continue to be complied with where possible. Nonetheless, as a contingency, SL has developed variations to some of its corporate arrangements in order to introduce some flexibility, but in a way which still maintains compliance with legal obligations. SL has put in place variations to its corporate arrangements which affect its arrangements for compliance with Licence Condition (LC) 10, 11, 12, 26 and 36. Prior to this intervention, ONR has reviewed the relevant variations and is satisfied that they are adequate. This inspection has included consideration of whether the variations have been used at PFCS, and if so, whether they have been complied with.

Interventions Carried Out by ONR

This inspection was carried out against LCs 10, 11, 12, 26 & 36. It sought to seek evidence of compliance in each case. However, it was recognised that given the remote nature of the intervention, a formal judgement of compliance would only be made should a sufficiently-sized sample of evidence be available under the circumstances. In this case, it was decided that a formal compliance rating was only possible against LCs 10, 11, and 12.

The inspections against LCs 10, 11, 12, 26 and 36 were linked by consideration of a common theme, Minimum Safe Manning Level (MSML).

The inspection began with a question and answer teleconference between the ONR inspection team with representatives from PFCS. This session was supported by evidence that had been requested in advance. Further evidence was requested and provided following this session and in some cases clarifications were sought by separate phone calls. The inspection concluded with a follow-up teleconference. Regulatory judgements have been made based on the verbal answers and supporting documentary evidence.

Explanation of Judgement if Safety System Not Judged to be Adequate

This was not a System Based Inspection and therefore this section is not applicable.

Key Findings, Inspector's Opinions and Reasons for Judgements Made

In relation to LC 10 and LC 12, the inspection focussed on training and demonstration of competence for operations associated with responding to an emergency at PFCS.  ONR found that compliance with SL’s corporate arrangements was being maintained and that there had only been limited application of a COVID-19 variation to SL’s corporate arrangements affecting these LCs. Nonetheless, I found some minor areas for improvement in relation to training and as such I have raised a Level 4 Regulatory Issue (the lowest level) for SL to address.  

In relation to LC 11, the inspection provided assurance that PFCS was maintaining its emergency arrangements in line with SL’s LC 11 arrangements.

In relation to LC 12, the inspection provided assurance that PFCS was maintaining its arrangements for assessing and appointing duly authorised and other suitably qualified and experienced persons in line with SL’s LC 12 arrangements.

In relation to LC 26, the inspection provided assurance that PFCS control and supervision of operations was in line with SL’s LC 26 arrangements. However, insufficient evidence was gathered to give a formal rating.

In relation to LC 36, ONR found that the MSML is defined by the need to respond to an emergency situation.  ONR recognised that PFCS has established additional contingency arrangements should the MSML be challenged by COVID-19.  To date these arrangements have not had to be implemented.  As was the case for LC26, insufficient evidence was gathered to give a formal rating. 

Conclusion of Intervention

The LC 10, LC 11 and LC 12 compliance inspection concluded that the licensee had adequately implemented its arrangements for the aforementioned Licence Conditions. I therefore consider, noting the ONR guidance on inspection ratings, that an inspection rating of Green (no formal action required) is merited here for the PFCS facility on the Sellafield Site.

A limited sample of evidence enabled ONR to gain assurance that in the case of LC 26 & LC 36 the PFCS facility was compliant with SL’s arrangements and no matters were identified that would require formal follow-up.