Pile Fuel Storage Pond (PFSP) is one of the most hazardous facilities on Sellafield Site. It contains a radiological inventory of sludge, oxide fuel, metal fuel and intermediate level waste. As part of the decommissioning process, a variety of different items need to be retrieved from or repositioned within the pond to allow effective clean-up to take place.The overall aim was to develop a long term arrangement to provide a quick, efficient and cost effective response to the challenges faced across the whole of the PFSP decommissioning programme for Sellafield Ltd. In order to progress projects cost effectively and speedily, the Sellafield project team looked for partners in the supply chain with the required experience, expertise and facilities to supply and test “commercial off-the-shelf” (COTS) or modified proprietary equipment. This COTS approach minimises the need for multiple, expensive and lengthy design and manufacturing tasks associated with bespoke equipment.
Understanding the requirements and ensuring these were being addressed by the project teams. Timescales were often very tight and this required responsiveness of both Sellafield and CNSL parties. Collaboration was vital across all the discussions and implementation of solutions. This was demonstrated throughout every level of the project organogram by allowing the SL employees responsible for deploying the equipment to fully engage with the engineering teams in the development of the solutions. This helped create a feeling of ownership and responsibility within the team.
Optioneering of potential solutions involves early “proof of principle” trials in the JFN rig hall, utilising COTS equipment and plant mock-ups, along with other prototype equipment manufactured in-house. Together the project teams select the best solution to take forward, adopting a practical and trials based approach, which allows rapid and cost effective modification of the solution throughout the project with minimal impact on the programme. When the final solution is validated, plant operators then gain familiarity and training in the use of the equipment, allowing them to execute the work efficiently on plant, and so minimise their dose uptake.
As well as adaptation of COTS tooling, CNSL have also designed and manufactured such items as Skip Lifting Beams, bespoke remotely operated Drum Grabs, specific waste lifting beams, long reach manual grabs, self-buoyant pneumatically operated magnets, and sludge retrieval equipment. CNSL have also undertaken extensive trialling in support of Safety Case substantiation and the achievement of specific Technical Readiness Levels (TRLs).The project teams from Sellafield and CNSL, led by specialist remote handling contractor, James Fisher Nuclear, worked closely together at every stage of the projects, from qualifying requirements, identifying potential solutions, through to development, testing, training and final deployment in PFSP.