“Wright-Patterson Air Force Base, Ohio, at least immediately after the incident.”
I worked on base for several years, still have a valid CAC card for WPAFB. As a building 18 (Propulsion directorate HQ) employee, we would occasionally laugh about “hangar 18” which doesn’t exist, but there was nothing in or below building 18. On the other hand, there is an (unclassified) base map which shows building levels and there were several which defined several more levels than any employee I knew had access to.