Office for Nuclear Regulation

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To conduct a system inspection and undertake routine regulatory interactions with Sellafield Limited

Executive summary

Purpose of intervention

This intervention was undertaken on 23 – 26 February 2015 at Sellafield Limited’s Sellafield nuclear licensed site in Cumbria.

Inspection of Licence Condition (LC) compliance at nuclear licensed sites forms a significant part of ONR’s activities.  ONR’s Sellafield Programme has defined a programme of system inspections and LC compliance inspections to be undertaken on the Sellafield site; this is a key aspect of ONR’s regulatory strategy (for the Sellafield site).  Undertaking this intervention is consistent with this strategy, and is identified on ONR’s PP4 inspection plan which covers Sellafield Limited’s Magnox Operating Unit.

Interventions Carried Out by ONR

The intervention comprised:

The purpose of the containment system within the MA evaporation and TDN plant is to prevent the leakage and escape of process fluids, and to facilitate the detection and containment of any leakage that does occur.  My system inspection sought to determine whether the containment system within the MA evaporation area of the MA evaporation and TDN plant meets the requirements of the safety case and is adequate.  The implementation of the Licensee’s arrangements for the following LCs were tested during the system inspection:

During my inspection I was accompanied by ONR structural integrity and process engineering specialist inspectors.  Our inspection included discussions with SL staff, review of plant instructions, records and other documents and an inspection of the plant.

I also attended meetings:

Explanation of Judgement if Safety System Not Judged to be Adequate

Based on sampling inspection, the containment system of the MA evaporation area of the MA evaporation and TDN plant was judged to be adequate and consistent with the requirements of the safety case.

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

For the containment system of the MA evaporation and TDN plant, I judged the following IIS ratings to be appropriate:

Based on my sample inspection, I judged that the containment system within the MA area of the MA evaporation and TDN plant is consistent with safety case requirements, the key equipment that verifies this is available and appropriately maintained, those responsible for operations are suitably trained and that appropriate written instructions are available.  I conclude the containment system meets the requirements of the safety case.

I also attended a progress meeting to discuss the planned import of legacy fuel to FHP.  The focus of the meeting was to clearly communicate my expectations of the prerequisites I would expect to be in place at FHP prior to the import of legacy fuel.  The licensee noted my views.

I attended a meeting to outline ONR’s likely approach to the regulation of the forthcoming Magnox Reprocessing periodic shutdown.  I confirmed that ONR would work closely with the Sellafield Limited Internal Regulator (SLIR) to gain assurance that the plant was safe to restart after the shutdown.  I confirmed ONR’s strategy is to issue a consent to restart the plant after the periodic shutdown provided the outcome of the assurance work undertaken by ONR and SLIR confirms this is safe to do.

I attended a meeting with senior managers from Magnox Reprocessing to discuss safety critical alarms.  I was reassured that the issues raised in my recent letter are being addressed and a programme of remedial work has been put in place.

Conclusion of Intervention

The issues raised in my system inspection will be managed to close out as part of normal regulatory interactions with the licensee. Based on the evidence gathered, no significant matters have been identified that are likely to impact on nuclear safety on the Sellafield site at this time.