Executive summary
Date(s) of inspection: March 2024
Aim of inspection
To seek assurance that Sellafield Limited’s arrangements for compliance with Licence Condition 32 (Accumulation of Radioactive Waste) and Licence Condition 35 (Decommissioning) are adequately implemented in Magnox Swarf Storage Silo (MSSS) and meet with the relevant expectations of ONR.The inspection was undertaken jointly with the Environment Agency, which assessed compliance with relevant Radioactive Substances Regulation (RSR) Environmental Permitting Regulations (EPR) Permit conditions.
Subject(s) of inspection
- LC32 - Accumulation of radioactive waste - Rating: Green
- LC35 - Decommissioning - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
I led a planned compliance inspection on the implementation of Sellafield Ltd arrangements for LC32 (Accumulation of radioactive waste) and LC35 (Decommissioning) in Magnox Swarf Storage Silo (MSSS). The inspection was completed jointly with the Environment Agency, which undertook its own assessment of compliance with the relevant environmental permit conditions relating to solid waste management and will issue its own report on the inspection. The inspection team consisted of the MSSS site inspector, two nuclear liabilities specialist inspectors, a developing nuclear safety inspector, and two Environment Agency inspectors.
For LC32, the inspection targeted the arrangements for solid radioactive waste arising in MSSS during retrieval operations, but excluding silo waste. Through sampling of arrangements, discussion with personnel and a plant visit, Sellafield Ltd provided evidence of the following in MSSS:
- There were suitable local arrangements in place for handling, segregation and temporary storage of radioactive waste to support compliance with LC32.
- There is adequate resourcing of Plant Solid Waste Coordinator and Waste Advisor roles.
- Facility Waste Generator training is in place for Sellafield Ltd staff and contractor waste supervisors in the facility.
- An inventory was in place to record the nature, quantity, duration and location of radioactive waste stored in dedicated laydown areas on the facility (including outside the building).
- Waste management issues were recorded using condition reports, with suitable trend analysis undertaken leading to appropriate improvement actions.
Based on the areas sampled, I provided some regulatory advice but did not find any significant shortfalls. Consequently, I judged that arrangements for compliance with LC32 were adequately implemented and considered a rating of Green (no formal action) to be appropriate.
For LC35, in view of the current stage in the facility lifecycle (that is, operational with silo waste retrievals expected to continue until the late 2040s), the inspection targeted the current status of the baseline decommissioning strategy and plans for MSSS. Through sampling of documentation and discussion with personnel, Sellafield Ltd provided evidence of the following:
- A decommissioning mandate, plant status report and plant strategy report have been developed for MSSS and set out a proportionate level of detail for the current stage in the facility lifecycle. These documents were produced some time ago and there have been some changes to assumptions since the documents were issued, particularly around decommissioning timescales. I considered this to be a minor shortfall given the current stage of the facility lifecycle and long timescales before decommissioning will start, and I provided Sellafield Ltd with regulatory advice to consider the purpose of these documents and whether they should be updated at this stage.
- The decommissioning programme for MSSS is incorporated in the site master schedule, with suitable logic linkage of interdependencies with other facilities needed to support decommissioning.
Based on the areas sampled, I provided some regulatory advice but did not find any significant shortfalls. Consequently, I judged that arrangements for compliance with LC35 were adequately implemented and considered a rating of Green (no formal action) to be appropriate.
Conclusion
Overall I was satisfied that MSSS is compliant with Sellafield Ltd corporate arrangements and meets ONR’s expectations for LC32. I observed some examples of good practice, but also identified two minor failures to implement compliance arrangements and a small number of minor shortfalls against relevant good practice for which I provided regulatory advice. I consider an inspection rating of Green (no formal action) to be appropriate.
I was satisfied that MSSS is compliant with Sellafield Ltd corporate arrangements for LC35 and overall meets ONR’s expectations with a small number of minor shortfalls against relevant good practice for which I provided regulatory advice. I consider an inspection rating of Green (no formal action) to be appropriate.