National Museum of Nuclear Science & History
Leslie Spalding worked for the United States Engineer District Office.
Anthony J. (“Tony”) Matz was a procurement officer at the University of Chicago Met Lab. He helped obtain, handle, and move many of the materials for Chicago Pile-1 and witnessed it going critical on December 2, 1942.
Acie Singleton was a laborator helper at the Metallurgical Laboratory in Chicago during the Manhattan Project.