National Museum of Nuclear Science & History
Walt Simon, a chemist, was Hanford’s first Operations Manager. Before joining the Manhattan Project, he was plant manager at Wabash River Ordnance Works, a DuPont plant near Terre Haute, Indiana.
Roy W. Carlson was an engineer. He worked on the Manhattan Project at Los Alamos and the University of California, Berkeley, as a member of the Explosives Division and Group X-2A.
Mars worked for Stone and Webster Engineering Corporation.