English: Hanford’s U Plant was the third plutonium processing canyon built at the Site. Stretching 810 feet long, 66 feet wide, and 77 feet high, it was constructed in 1944. While originally designed to perform the chemical separations activities needed to extract plutonium from irradiated fuel rods, it was determined after construction was complete that the first two canyons would be able to process enough plutonium without needing to use U Plant for the same purpose. As a result, U Plant became a facility where T Plant and B Plant workers were trained before they were permanently assigned to either of those canyons. In 1952, the U Plant was given a new mission which was to recover uranium from the waste generated in the plutonium extraction process. For six years, U Plant crews removed uranium from the chemical separations process waste and then transferred that uranium to a support facility called 224-U/UA (224-U/UA was also called the UO3 or Uranium Trioxide Facility).