Last updated: August 22, 2023
US Army Colonel Leslie Groves, from Albany, New York, was appointed head of the Manhattan Engineer District on September 17, 1942. Upon his appointment to lead this top-secret project, Groves wasted little time getting to work. The following day he acquired 1250 tons of uranium mined from Africa’s Belgian Congo. One day later, September 19, he approved Oak Ridge, Tennessee, as the location of Site X, a secret uranium-enrichment facility. On September 23 he was appointed Brigadier General.
By mid-October 1942, Groves had secured a contract with the DuPont corporation to oversee plutonium production, visited the Met Lab at Chicago, and chose physicist J. Robert Oppenheimer to lead Project Y, of which Groves would approve its location in Los Alamos, New Mexico on November 25, 1942. On January 16, 1943, Groves approved Hanford, Washington as the site for the Manhattan Project’s massive plutonium-production facility.
During his tenure as head of the Manhattan Project’s operations, Groves oversaw the efforts of over one hundred thousand workers and scientists, observed the Trinity Test first-hand on July 16, 1945, and stayed in his role after the war until late 1947, when the newly-created Atomic Energy Commission took control of the Manhattan Project. Groves retired as a Lieutenant General on February 29, 1948.