National Museum of Nuclear Science & History
R. O. Irwin worked for the Tennessee Eastman Corporation at the Y-12 Plant.
Calvin B. Popwell served as a corporal in the 393rd Bombardment Squadron. He was a member of the ground crew regularly assigned to the B-29 Big Stink, and he and his crew were later reassigned to Luke the Spook.
Welch worked at the 200 West Area at Hanford during the Manhattan Project.