National Museum of Nuclear Science & History
Zen B. Portwood worked for the J.A. Jones Construction Company.
William S. Johnston was a research assistant at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.
John H. Martens was a research associate and chemist at the University of Chicago Met Lab and a member of the Special Engineer Detachment at Oak Ridge.
L. J. Turner worked for the United States Engineer District Office.
