1,936 highly radioactive capsules of cesium and strontium are currently being stored underwater at Hanford’s Waste Encapsulation and Storage Facility (WESF). This material was retrieved from Hanford’s tanks in the 1970’s to reduce the temperature inside the tanks.
Although the capsules are currently being stored safely, the unlikely event of a significant earthquake or other similar significant event could lead to water loss from the storage pool, which could result in overheating and capsule breach. The Department of Energy and contractor Central Plateau Cleanup Company are working to move the capsules into dry cask storage to further reduce risks. Transfer of the capsules from the pool into casks is scheduled to begin in 2025, and will be complete within 2-3 years.
