William F. Schaffer, Jr.

J. E. Boltz

Helena Calloway

Helena Calloway was a laboratory assistant in the Chemistry Division of the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.

Nathan C. Safferstein

Nathan Safferstein (1921-2013) was an American counterintelligence agent during the Manhattan Project.

C. W. Danford

C. W. Danford worked at the 100-D Area at Hanford during the Manhattan Project.