National Museum of Nuclear Science & History
Gertrude Steel was a junior chemist at the Metallurgical Laboratory in Chicago during the Manhattan Project.
Webb worked for Stone and Webster Engineering Corporation.
Jack L. Callan was a laborer at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.
Arnold Grubbe (1904-2002) was an engineer working for the civilian contractor Crane Company in Oak Ridge, Tennessee.