Crews with U.S. Department of Energy Office of Environmental Management contractor Central Plateau Cleanup Company recently began assembling a cask storage system for 1,936 radioactive capsules at the Hanford Site. When fully loaded, each concrete cask will weigh up to 170,000 pounds.
RICHLAND, Wash. — U.S. Department of Energy Office of Environmental Management (EM) contractor Central Plateau Cleanup Company has begun assembling a cask storage system that will support moving almost 2,000 radioactive capsules out of a water-filled basin into safer dry storage, a significant step in risk reduction at the Hanford Site.
In the mid-1970s, workers removed cesium and strontium from waste in Hanford’s underground storage tanks to reduce the waste temperature. At Hanford’s Waste Encapsulation and Storage Facility (WESF), workers placed both elements in sealed, stainless steel capsules for safe storage under 13 feet of water. The water provides shielding from radiation and keeps the capsules from overheating.
Workers will begin transferring the capsules from the WESF basin next year into large concrete casks for air-cooled storage on a secure, concrete pad near the facility. Dry storage will eliminate the possibility of a release of radioactive material in the unlikely event of a loss of basin water, and subsequent overheating and breach of the capsules.
“The dry storage configuration also paves the way for eventual decontamination and demolition of the WESF facility,” EM Federal Project Director Gary Pyles said. “Deactivating the facility will reduce operating costs, eliminate a risk in our cleanup operations and keep the Hanford mission moving forward.”
A transportable storage container is a key component of the cask storage system for 1,936 radioactive capsules on the Hanford Site. The capsules will be moved from an underwater basin in Hanford’s Waste Encapsulation and Storage Facility and placed in concrete casks for safe, interim dry storage.
Workers modified WESF last fall to support the transfer of capsules and they are installing and testing remote-operated equipment to move capsules from the basin into a shielded room for inspection. The capsules are loaded into protective sleeves filled with helium, which helps dissipate heat.
They will then load the sleeves in a container that fits in a large, reinforced concrete cask that provides shielding and weighs up to 170,000 pounds when fully loaded.
After workers move the casks to the outdoor storage pad, airflow keeps the temperature of the sealed capsules within safe limits. This is similar to how spent nuclear fuel from commercial nuclear plants is stored.
The capsules contain about a third of the radioactivity on the Hanford Site.
WATCH THIS: Timelapse video highlights assembly of the cask storage system.
Source: EM Update Newletter