Historic Markers Across Tennessee

K-25 – The Gaseous Diffusion Plant

Marker ID:  
Location: Alvin K. Bissell Park, at the intersection of Oak Ridge Turnpike (Tennessee Route 95) and South Tulane Ave, Oak Ridge, TN
County: Anderson
Coordinates: N 36° 0.817    W 084° 15.474
  36.01361666    -84.2579
Style: Mounted **
Waymark: None


K-25 – The Gaseous Diffusion Plant

In 1940 Columbia University scientists led by John Dunning began their research to beat Germany to the atomic bomb. But it took four years before they learned how to make the key to the gaseous diffusion process – a very porous, strong “barrier” with holes tiny enough to separate the rare uranium-235 from U-238. The diffusion step must be repeated about 3,000 times to produce nearly pure U-235, so the plant had to be huge – 40 acres under one roof – in a “U” shape with “legs’ a half mile long, 400 feet wide, and four stories tall. In September 1943, ground was broken for the $512 million plant called K-25, and amazingly, in view of its complexity and new technology, operation began in February 1945. The largest of any Manhattan Project facility, K-25 was built as a backup in case Y-12 did not succeed. Because the continuous K-25 process proved workable and far cheaper, it replaced Y-12 as the nation’s U-235 supplier. The Kellex Corporation headed the brilliant design of the process and plant. The K-25 powerhouse, built in 1944, was the largest steam generating station ever built at one time. Carbide and Carbon Chemicals Corporation was the first K-25 plant operator. The general manager for Carbide in the 1943-1944 building period was George T. Felbeck; in the 1945 startup year, H.D. Kinsey; and in 1947, Clark E. Center, who had a two-decade tenure. At the urgent request of the government in 1949, when the arms race began, K-25 personnel planned and oversaw the four-fold expansion of America’s U-235 production capacity, which later fueled peacetime nuclear power plants around the world.

Erected in Honor of the Scientists, Engineers, and All Other Individuals Who Designed, Constructed, and Operated this Vital Facility of the Manhattan Project
By Bechtel Jacobs Company, LLC, June 2005.


More information:
Wikipedia - Oak Ridge, Tennessee
Wikipedia - Manhattan Project
Wikipedia - Manhattan Project National Historical Park
US History for Kids - Manhattan Project Timeline
Secret City Commemorative Walk