National Museum of Nuclear Science & History
John Luttrell worked for the United States Engineer District Office.
Calderwood worked at the 200 East Area at Hanford during the Manhattan Project.
General Lyle Edward “Skip” Seeman was a United States Army Corps of Engineers Officer. He was also a Manhattan Engineering District Special Assistant to General Groves at Los Alamos On May 3, 1945 Col Seeman was appointed by General Leslie Groves to be his Corps of Engineers liaison at Los Alamos.
Gilbert Plass was a Canadian physicist. Plass was born in 1922 in Toronto. He received a B.S. in physics from Harvard University before being hired to work on the Manhattan Project at the Chicago Met Lab, where he worked as an associate physicist.