Cesium/Strontium capsules in underwater storage
Highly radioactive capsules stored underwater at the Waste Encapsulation Storage Facility. The capsules contain radioactive isotopes called cesium and strontium, byproducts of plutonium production. A total of 1,335 cesium capsules and 601 strontium capsules are stored at the facility beneath 13 feet of water. The water both shields workers from radiation and keeps the capsules cool. The water in the pools glows blue, in an effect known as the Cherenkov Glow, as the radioactive cesium and strontium decay and lose their radioactivity to become stable atoms.