Date(s) of inspection:
- January 2023
Aim of inspection
Subject(s) of inspection
- IRR17 – Rating: Green
Key findings, inspector’s opinions and reasons for judgement made
I undertook an inspection of Thermal Oxide Reprocessing Plant (THORP) implementation of the Sellafield Site arrangements for LC35 (Decommissioning).
The focus of the inspection was on changes relevant to decommissioning of THORP since the last inspection in May 2021, specifically sampling against the Low Pressure (LP) and High Pressure (HP) wash out of the Shear Cave as an example of a Post-Operational Clean Out (POCO) project. In light of recent events related to control of effluents within THORP and THORP’s decision to take a safety stand down, I decided to also focus on controls around planning (including radioactive waste management) and arrangements around Learning from Experience activities of this POCO activity.
Additionally, given the pending Management of Change (MoC) under LC36 (Organisational capability) the inspection sought to understand how the competence of persons involved in the implementation of the POCO / decommissioning activities on the THORP plant is being considered.
From the inspection sample of the LP and HP wash outs of the Shear Cave I found that THORP, through the Plant Modification Proposals provided adequate consideration of a number of areas of relevant good practice, as captured in ONR’s guidance. The sample included consideration of:
- Isolations for the management of radioactive effluents generated from the wash down activities.
- Lessons learnt from the LP wash out activities, working with the Sellafield Central POCO Team and informing planning for the HP wash out (due to commence February 2023).
- Solid waste management / compatibility with waste routes, made through engagement with the Plant Solid Waste Coordinator.
- Development of Training Programme Descriptors to support POCO / Decommissioning ahead of the LC36 MoC to ensure operators are suitably qualified and experienced personnel.
During the plant walkdown I raised minor observations and provided regulatory advice on opportunities to improve the temporary barrier controls and conventional health and safety aspects. I also provided regulatory advice for THORP to implement a programme of assurance reviews in accordance with the relevant Sellafield Ltd LC35 arrangements and on ensuring adequate records of the wash out activities are retained to support the movement from POCO / decommissioning into the Surveillance and Maintenance period.
Overall, based upon the evidence gained during the inspection I was satisfied that the THORP facility is adequately implementing the Sellafield Ltd LC35 arrangements. I am, therefore, content to rate LC35 as Green (no formal action). No regulatory issues have been raised from this inspection
Overall, based upon the sample during the inspection I was satisfied that the THORP facility is adequately implementing the Sellafield Ltd LC35 (Decommissioning) arrangements. I am, therefore, content to rate LC35 as Green (no formal action). No regulatory issues have been raised from this inspection.