National Museum of Nuclear Science & History
Harold Hoover was a member of the Special Engineer Detachment during the Manhattan Project. He worked as a filter foreman at the Y-12 Plant, but his real job was in counterintelligence, to ensure no sabotage occurred.
M. J. McDaniel worked for Clinton Laboratories at the X-10 Reactor.
H. F. Jacobsen worked for the Union Carbide & Carbon Corporation.
