National Museum of Nuclear Science & History
Harold Hasenfus was part of the Special Engineer Detachment during the Manhattan Project and worked at the University of Chicago's Metalurgical Laboratory and at the gaseous diffusion plant in Oak Ridge.
Robert Ellingson arrived in Oak Ridge in June 1943. Shortly after Ellingson arrived, however, he was informed by his employer, Tennessee Eastman, that they already had too many chemists and chemical engineers.