On December 26, 1944, the first batch of irradiated uranium cylinders from the B Reactor was moved by railcar to the T Plant, where plutonium would be extracted for use in the Trinity Test and the bombing of Nagasaki

B Reactor is composed of 2,004 tubes into which 60,000 cylinders of Uranium 238 fuel was inserted. Water from the Columbia River was pumped through a tiny annulus space around the fuel slugs for cooling. Over about 100 days, the now lethally-irradiated slugs would be shoved out the back like a pez dispenser and dropping down a 30-foot chute into a pool of water, where they would spend about 3 months cooling.

The fuel slugs would then be retrieved by workers with long poles tipped by grasping claws and moved by train to a processing plant. A single cask car loaded with fuel slugs was generally pulled behind a locomotive, separated by 10 empty rail cars to keep the train operators safe from radiation. For the same reason, trains moved at night to prevent dosing people waiting in their cars at train crossings.

A the T Plants, plutonium was extracted from the fuel slugs. The T Plant was divided into 40 cells, each with 7-foot thick walls, to accomplish the three steps needed to extract plutonium from reactor slugs: solution, precipitation, and centrifuge removal of precipitate.

One witness to the first step, dissolving the irradiated fuel slugs in nitric acid, said, “Brown fumes blossomed above the concrete canyons, climbed thousands of feet into the air, and drifted sideways as they cooled.”

Two end products were created. Radioactive waste was stored on site in underground tanks while pure plutonium nitrate was sent to the secret atomic bomb making laboratory at Los Alamos, New Mexico. The plutonium produced at Hanford was used in the first atomic bomb test in July of 1945, and in the Fat Man atomic bomb exploded over Nagasaki, Japan on August 9, 1945.1 ton of uranium would yield about half a pound of plutonium, with the rest of the dissolved metal, solvents, and sludge rendered a highly radioactive waste substance. About 56 million gallons of this waste is currently stored in their original underground tanks, extremely close to the Columbia River.