The entire story is absolutely astounding isn’t it?
The story also goes that development of the B-29 was an undertaking of similar magnitude though I find that hard to believe.
Hanford works alone had 50,000 laborers at one time and most had no idea what they were building.
I knew a guy from a town in Western Oklahoma that was nabbed right after he graduated as an electrical engineer from OAMC. They put him on the group responsible for provision of electrical power grids at Los Alamos and told them if the power ever went out they would all be dead. Probably a little drama there.
Yeah, the B-29 work needed to get the platform able to drop the bomb reliably and get people back was quite extensive. They had essentially rushed the B-29 into service before it was ready, and Tibbits had to redo a lot of their testing work and modification recommendations, including making the bomb bay doors larger to accommodate the size of the weapons.
Think of Oak Ridge in addition to Hanford. The sheer size of these sites and the number of people involved, and that they were able to keep most of this under wraps was just amazing.
I grew up in Los Alamos (many years afterward) and it is small potatoes compared to Hanford and Oak Ridge.