One of Hanford’s earliest plutonium processing facilities was the B Plant located in the 200 East Area. The fuel rods which had been irradiated in the nuclear reactors at Hanford were taken to the B Plant where the rods went through a series of chemical baths to remove the plutonium from the rods. Because chemicals were needed to separate the plutonium from the fuel rod, facilities like the B Plant were also called chemical separations plants. Once the plutonium had been removed from the fuel rods it was further processed to be used in America’s stockpile of atomic weapons. All of the chemicals needed to extract the plutonium as well as the excess parts of the irradiated fuel rods became waste.
The B Plant operated from 1945 through 1957 when it was shut down. Eleven years later, in 1968, the plant was modified and restarted. Its new mission was to separate the radioactive elements cesium and strontium from the tank waste that was generated when the plutonium was extracted from the irradiated fuel rods processed at B Plant. The cesium and strontium campaign ended in 1985; the canyon was ultimately deactivated in 1998.
The cesium and strontium that was removed is now stored in more than 1900 capsules located in a facility adjacent to B Plant called the Waste Encapsulation Storage Facility (WESF). WESF was built specifically to house these highly radioactive capsules which are safely stored in a water filled basin at the WESF while they await a permanent disposition at a national repository.