Inside Hanford's T Plant: A Panoramic Tour of the First Plutonium Separations Plant

Hanford's T Plant, the world's first plant built to chemically separate radioactive materials. NPS.

The world's first separations plant

Built during the Manhattan Project, Hanford's T Plant was the first plant in the world built to chemically separate radioactive materials. Much of the work was done remotely, to protect workers from the intense radiation of irradiated uranium fuel slugs. People had separated metals with heat and chemicals for millennia, but never a man-made element from highly radioactive fuel, at industrial scale.

• The goal: about half a pound (250 g) of plutonium a day from one ton (907 kg) of irradiated uranium — like pulling a hamster's weight out of a mass as heavy as a car.
• The chemistry: developed by University of California chemist Glenn Seaborg, whose first experiments used micrograms of plutonium. T Plant used a billion times the chemicals he used in the lab.

The building

T Plant is a concrete box 875 feet (266.7 m) long, 65 feet (19.8 m) wide and 85 feet (26 m) tall.

• Along one side run three stacked galleries the length of the building: the electrical, pipe and operations galleries.
• Beside them lies the canyon: 40 concrete cells where the chemical separation took place.

The west end of T Plant under construction. U.S. Department of Energy.

In the construction photo, thick concrete walls shield workers. At lower left is the underground electrical gallery, with the pipe gallery and then the operating gallery stacked above. The space at upper left is the crane way for a huge 75-ton (68 t) crane that ran over the canyon. The plant also had offices and rooms for mixing the separation chemicals.

The electrical gallery

The lowest staffed level, running alongside the canyon, holds all the building's electrical circuitry. T Plant has run continuously since 1944, so much of the circuitry has been upgraded — though many original panels are still in use.

The electrical gallery during the Manhattan Project. U.S. Department of Energy.

The electrical gallery today, a wraparound panorama shown flattened. NPS.

The pipe gallery

Steam, water and the process chemicals came in through the pipe gallery. Radioactive solutions never passed through it — they stayed on the canyon side — so no special shielding was needed here.

The pipe gallery during the Manhattan Project. U.S. Department of Energy.

The pipe gallery today, a wraparound panorama shown flattened. NPS.

The canyon and its crane

To limit workers' exposure, the canyon was designed to run by remote control — which meant inventing equipment that worked without hands-on handling: a crane with several hooks and capacities, impact wrenches, and piping whose valves opened and closed with impact-wrench fittings.

• The crane spanned 58 feet (17.67 m) across the canyon; its bridge carried the hooks across a 32-foot (9.75 m) working range.
• Its hooks and hoists let the operator lift cover blocks, move equipment in and out of each cell, and add or remove liquid and electrical jumpers — all remotely.

The remotely operated crane in the separations canyon. U.S. Department of Energy.

The operations gallery

There were no openings between the galleries and the canyon, so workers monitored and controlled the separations from the operations gallery.

Remotely controlling the separations in the operations gallery. U.S. Department of Energy.

Gardner C. Blackburn, who started at T Plant in 1943, described the work in 1999: batches came one after another, with an operator on each section's board. Before any material moved between tanks, he had to unlock the board; steam jetted the solutions and air cooled the lines before they were locked again — so he walked the gallery constantly. He kept the keys and the shift log, which told operators how long to let solutions settle and which chemicals to add, and in what amounts, with each step signed off.

The operations gallery today, a wraparound panorama shown flattened. NPS.

The waste

Once the plutonium was out, the leftover uranium, unwanted radionuclides and dissolving chemicals became liquid waste, sent to underground tanks.

Building the 241-T tank farm to hold liquid waste from the separations. U.S. Department of Energy.

• The 241-T tank farm had 12 large tanks, each 75 feet (22.86 m) across and 16 feet (4.87 m) deep, holding about 530,000 gallons (2,006,268 l).
• Tanks were linked in cascades of three: as the first filled, it spilled into the second, then the third.
• Today the legacy of the Manhattan Project and Cold War plutonium production is about 56,000,000 gallons (211,983,060 l) of highly radioactive liquid waste, much of it stored for nearly 80 years, still managed by Hanford contractors for the Department of Energy.

What T Plant made — and does now

• Plutonium from T Plant went into the Trinity test on July 16, 1945, and the Fat Man bomb dropped on Nagasaki on August 9, 1945.
• It stopped separating plutonium in 1956, returned in 1957 as a decontamination, repair and waste-handling facility, and today provides interim storage for radioactive sludge from a fuel storage basin near the Columbia River.

Sources

Based on "Hanford: T Plant Panoramic Tour," Manhattan Project National Historical Park, National Park Service; a work of the United States government in the public domain. The three panoramas, which the imported page had lost, were recovered from the Park Service's NPGallery, where they are marked public domain.