N. J. Zammarrelli

Ralph G. Steinhardt, Jr.

Ralph Steinhardt was a member of the Special Engineer Detatchment (SED) at Los Alamos during the Manhattan Project.

Joseph L. Hayes

H. L. Ray

H. L. Ray worked for the Kellex Corporation at the K-25 Plant.

Anthony J. Matz

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.