Paducah Site in Kentucky is were we operate the gaseous diffusion facility, which was producing HEU from 1952-2013 (ORNL operated the uranium enrichment program prior to 1952 at K-25.)

It was in basically full production for the extent of this period, but total volumes produced is classified. There are hundreds, if not thousands of tons 95%+ UF6 in the US inventory.

That's so so much longer, more and of higher grade than I expected. That's a treasure trove for nuclear science, private developments and civil power generation. I should have assumed that given the amount of warheads build that the amounts would be so high. 95%+ is crazy that must be a real bitch to handle given criticality concerns.

Super grade 239 sounds fascinating as well.

I read up on it a little and the gun type warheads where used until 92! Sort of surprising but apparently it has advantages in bunker busting due to its simplicity over implosion types. Here I was thinking little boy was the only one of its kind aside from whatever south Africa might have build.