National Museum of Nuclear Science & History
Arthur Sievert worked for Hanley & Company.
Dr. Theron G. Finzel was a chemical engineer/chemist. He worked for DuPont, and was asked to help on the Manhattan Project.
Francis Oley worked on the Manhattan Project for the Kellex Corporation. The son of Polish immigrants, Oley grew up in Brooklyn, New York.
Hayes worked at the 300 Area at Hanford during the Manhattan Project.