Arguably the second most historic building at Hanford is the T Plant.
This facility is historic in that it’s the oldest remaining nuclear facility in the country that is still operating with a current mission. However, it is also historic as it’s the “canyon” where the plutonium used in both the world’s first atomic explosion (the Trinity Test) and in the Fat Man bomb dropped over Nagasaki, Japan in World War II was processed.
The T Plant was the first chemical processing and separations plant of its kind in the world. Construction began in 1943, with the plant becoming operational in 1945. Nicknamed the “Queen Mary” since T Plant was long and thin like the well known ocean liner, this facility was used to take the irradiated fuel rods that had been in the B Reactor and expose them to a series of chemical processes. The chemicals were needed to dissolve away the fuel rods themselves, allowing workers to access and then extract the tiny amount of plutonium that was produced when the rods were involved in nuclear chain reactions in the reactors.
Once the plutonium had been extracted, the chemicals used to dissolve away the fuel rods became liquid wastes, and were put into the underground waste storage tanks at Hanford. The plutonium was further treated so that it could be used in atomic weapons.
Today, T Plant is a decontamination and repair facility where employees treat, verify, and repackage waste, as well as sample gases trapped inside drums of waste which have been removed from burial grounds throughout the Site. Radioactive and hazardous wastes are processed and packaged at the facility to meet state and federal regulations as well as criteria associated with transporting waste to certain specific waste disposal facilities. The T Plant Canyon Building is being evaluated for receiving, storing, and treating the radioactive sludge that has been containerized within the K-West Basin (see K-Basins).
T Plant is the only processing canyon at Hanford that remains in operation, although its mission today does not have anything to do with producing plutonium for weapons. The B Plant, S Plant (REDOX), U Plant, and PUREX are the other four processing canyons at Hanford which have long been shut down for all missions.