National Museum of Nuclear Science & History
Riser worked at the 200 West Area at Hanford during the Manhattan Project.
Jacob Epting worked as a carpenter in Oak Ridge, TN from November 1942 to October 1943. While Epting assumed he was building a hospital, he was never formally told about the project he was working on.
Johnstone worked at the 300 Area at Hanford during the Manhattan Project.
Marshall Holloway was an American physicist. He received his PhD in physics from Cornell University. In 1942, he directed a secret Manhattan Project assignment at Purdue University.
