Oak Ridge National Laboratory

Established during World War II by the Manhattan District, Oak Ridge National Laboratory (ORNL) occupied the X-10 site on the fifty-six-thousand-acre reservation between Clinch River and Black Oak Ridge purchased by the U.S. Army Corps of Engineers in 1942. Initially called Clinton Laboratories after the nearest town, it began as a top-secret installation to produce plutonium for the first nuclear weapons.

While the K-25, Y-12, and other plants at Oak Ridge experimented with different processes to separate uranium 235 from natural uranium 238 to produce fissionable enriched uranium for nuclear bombs, the X-10 site (ORNL) experimented with the production of fissionable plutonium 239 from uranium 238. At the X-10 site in 1943, engineers, working from the theories and processes developed by Albert Einstein, Enrico Fermi, and Glenn Seaborg and from the designs of Eugene Wigner, Alvin Weinberg, and colleagues of the University of Chicago, built the world’s first powerful nuclear reactor for transforming uranium into plutonium, along with the “hot cells” needed to chemically separate the precious plutonium from uranium.

In 1944 plutonium produced at X-10 (ORNL) went to laboratories at the University of Chicago, University of California, and Los Alamos, New Mexico, for experimentation. The designs and processes developed at X-10 served as the pilot plant for the larger reactors and chemical separation plants built by the Manhattan District that year at Hanford, Washington. Plutonium became the nuclear explosive used in the “Fat Man” bomb dropped at Nagasaki, while the enriched uranium produced at other Oak Ridge installations went into the “Little Boy” bomb used at Hiroshima. Using graphite to moderate neutrons, the X-10 Graphite Reactor at ORNL served the pioneering nuclear science field until 1963, when the reactor was shut down. The Graphite Reactor opened to the public during the 1980s as an educational exhibit and the world’s oldest surviving nuclear reactor.

In 1948 the X-10 site was officially designated the Oak Ridge National Laboratory and managed successively by the University of Chicago, Monsanto Chemical, Union Carbide, and Lockheed Martin corporations for the Atomic Energy Commission (1947-74), and later the Energy Research and Development Administration (1975-77) and Department of Energy (1977-present). During its early decades, ORNL focused on developing new types of atomic reactors and training nuclear scientists and engineers. Among the fourteen nuclear reactors designed at ORNL, most notable were its experimental materials testing, aqueous homogeneous, transportable package, and molten salt reactors. A participant in experimental gas-cooled and thermal breeder reactor development, ORNL contributed to the design of aero and naval propulsion, commercial, and liquid metal breeder reactors.

As national emphasis on nuclear and atomic energy waned, ORNL directors Alvin Weinberg, Floyd Culler, Herman Postma, Alex Zucker, Alvin Trivelpiece, and their associates expanded the Laboratory’s scientific research programs to include fusion, fossil, and renewable energy sources along with high-energy physics, environmental, biological, robotics, advanced materials, and allied sciences of national significance. These involved many cooperative programs with universities and schools in Tennessee as well as throughout the nation. During the 1990s ORNL became deeply involved in Department of Energy efforts to clean up the legacy of toxic and radioactive wastes generated in earlier years, both at its own facilities and throughout the nation and world. National policy mandated that ORNL speedily transfer its technologies to American industry and thereby enhance national economic competitiveness in the global marketplace.

Not only has ORNL affected the local economy of East Tennessee by providing opportunities for highly skilled and technical employment in the region, but the global and intellectual impact of the Laboratory can be seen in its role in developing scientists and engineers who have contributed to the advancement of knowledge and education around the world. Among the outstanding scientists and engineers associated with ORNL are Waldo Cohn, Alexander Hollaender, and William and Lianne Russell in radiation biology; Stanley Auerbach in radioecology; Ellison Taylor and Sheldon Datz in radiation chemistry; P. R. Bell and Karl Morgan in radiation dosimetry; and Ernest Wollan, Michael Wilkinson, and Clifford Shull in neutron physics.

Suggested Reading

Leland Johnson and Daniel Schaffer, Oak Ridge National Laboratory: The First Fifty Years (1994); Alvin Weinberg, The First Nuclear Era: The Life and Times of a Technological Fixer (1994)

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  • Article Title Oak Ridge National Laboratory
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  • Website Name Tennessee Encyclopedia
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  • Access Date June 17, 2024
  • Publisher Tennessee Historical Society
  • Original Published Date
  • Date of Last Update March 1, 2018