In 1943, General Leslie R. Groves, commander of the Manhattan Project, delegated to Colonel Kenneth D. Nichols the responsibility for administering what was to become a $2.2 billion effort. The Colonel had his headquarters here in a rambling, seven-wing frame-building where the Federal Building now stands that became known as "The Castle", and ran both the project here and most of the national effort. Throughout the war, technically trained soldiers on duty elsewhere were identified by the Army and reassigned to the Project. They made important contributions to the Project's success in Oak Ridge, Hanford, and Los Alamos. This Special Engineer Detachment (SED) here included 1,257 men. Also serving here was a detachment of the Women's Army Corps (WACS). Shortly after the war, Colonel Nichols wrote that the Manhattan Project was an "accomplishment which will endure as a monument to the ingenuity, vision and determination of all those from scientists to laborers, who have had a part in the work...these people and their organizations deserve unlimited credit for the successful accomplishment of an almost impossibly vast and complicated task." In 1947, operations were transferred to civilian control with the creation of the U.S. Atomic Energy Commission (AEC). For the next three decades, the AEC superbly managed its national
defense mission and the application of nuclear science to medicine, agriculture, industry, and energy to the great benefit of mankind. The AEC was a predecessor agency of the U.S. Department of Energy - a cabinet level agency responsible for programs in national security, science and technology, energy security, and environmental management.
Erected in Honor of the Manhattan Project and U.S. Atomic Energy Commission Personnel Who Lived and Worked in the Secret City 1942-1949 by The United States Department of Energy, June 2005.