Comment by dboreham

There's nobody around there but the fallout plumes traveled far generally into the north east of the site. Also depends on weather since the particles have to be brought down to ground level e.g. by rain. Places like St George Utah had particularly high amounts but also the area to the north of there through to south west Montana.

I think the John Wayne movie was filmed in an area outside St George called Snow Canyon. It's a state park so if you're inclined you can go there with a Geiger counter.