I mean if anything that seems like a reason not to move anything, since it is the only place in the US covered by that restriction, if anything if they weren't protected by the restriction then a coverup might be attempted or indeed just cease the practice of open pit burning re: those materials. That was related to the F117 program, there seems to be evidence of the base being used after that for the likes of the B2 program etc... and it is seemingly still used today so it isn't clear what exactly is supposed to have been moved in the first place? (Some chemicals from a discontinued fighter jet program that has since been superseded by the F22 and in turn potentially the F35. Possibly but some hazardous chemicals being moved != "Area 51 has moved").