National Museum of Nuclear Science & History
M. S. Headley worked for the J.A. Jones Construction Company.
John Arnold joined the Manhattan Project in 1943 when the MED tasked his employer, the Kellogg Corporation, with developing a special barrier for the gaseous diffusion plant in Oak Ridge.
Donald Todd was a staff worker at Los Alamos during the Manhattan Project.
J. M. Ryan worked for the United States Engineer District Office.