Sellafield has announced the successful completion of a challenging operation to remove radioactive material from one of its ageing storage tanks, originally constructed in the 1950s. The intricate process saw teams safely transfer a substantial volume of radioactive sludge, known as flocculant, into modern containment facilities, marking a significant step in reducing environmental risk at the nuclear site.
The flocculant, a byproduct from early reprocessing operations, had settled and compacted over decades within the legacy tank, making its removal a complex technical challenge. To overcome this, engineers and operators recommissioned specialist resuspension equipment. Water was added to the tank, and the contents were continuously mixed for approximately three weeks, 24 hours a day, to gradually break up the settled material and bring it back into a uniform suspension.
This meticulous approach allowed for the safe transfer of 1,302 cubic metres of the reconstituted radioactive sludge. To put this volume into perspective, it equates to more than half the capacity of an Olympic-sized swimming pool. The material has now been moved into a modern storage tank that feeds into Sellafield’s Enhanced Actinide Removal Plant, where it will undergo further treatment to ensure its safe and stable long-term storage.
Alan Prince, Head of Operations at Sellafield, emphasised the importance of the operation, stating that reducing legacy risk safely is central to their mission. He highlighted the collaborative effort and expertise demonstrated by the teams in executing such a demanding engineering and operational task. This achievement not only removes radioactive material from ageing infrastructure but also establishes a clear treatment route for its eventual disposal.
The successful completion of this project is part of Sellafield's broader commitment, under the Nuclear Decommissioning Authority, to reduce risk, protect the environment, and deliver value for taxpayers. There are two further legacy tanks at the site that will require similar emptying operations in the future, building on the experience and methods developed during this recent success.