Office for Nuclear Regulation

Dounreay - Project Based Inspection of Dounreay Cementation Plant Stores

Executive summary

Purpose of Intervention

The purpose of this inspection was to undertake a safety case informed (project based) inspection at Dounreay Site Restoration Limited (DSRL) in accordance with the 2018/19 Integrated Intervention Strategy (IIS) for Dounreay to confirm that the licensee is controlling its hazards and complying with its statutory obligations.

Interventions Carried Out by ONR

The inspection was focused on the Dounreay Cementation Plant (DCP) Interim Drum Store (IDS) and Store Extension (SE) (hereinafter collectively referred to as the DCP Stores).  The PBI examined the suitability of the safety case and its implementation against the requirements of the following licence conditions (LC):

Explanation of Judgement if Safety System Not Judged to be Adequate

We consider that safety systems we examined to support the DCP Stores to be adequate against the requirements of the above licence conditions.

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

With regards the PBI conducted at the DCP Stores, we examined the staff’s understanding of the key outcomes from the safety assessment of the storage of radioactive waste packages.  We then examined how the limits and conditions identified within the safety assessment had been captured and reflected in the associated operating instructions and the maintenance of safety related plant and equipment.  This inspection included a plant visit to DCP Stores, where we took the opportunity to assess the understanding operators had regarding the hazards and associated limits and conditions associated with the activities being undertaken at that time.  Finally we sampled the training undertaken by operations staff and also for one of the Shift Supervisors, and we examined how the arrangements sampled addressed the requirements regarding the leakage and escape of radioactive material and radioactive waste.

Overall we were satisfied that the limits and conditions and safety related plant and equipment identified within the safety assessment had been adequately captured within the associated operational and maintenance documentation reviewed; that the training records examined reflect the level of understanding expected of staff; and that the arrangements provide an adequate demonstration against the requirements regarding the control of leakage and escape of radioactive material and radioactive waste.

Conclusion of Intervention

Overall, we consider that the safety justification supporting the storage of radioactive waste packages within DCP Stores has been implemented adequately against the requirements of those licence conditions covered by the PBI.  We did not identify any matter impacting on nuclear safety that required any further immediate regulatory action.