The NTS is cleaner than you might expect it to be. My recollection of the radiation near Sedan crater is around 25uR/hr. I don't know if that is
beta+gamma or just gamma. I assume Groom is just as clean with the exception of the alpha contaminated area.
I've brought my geiger counter to Project Faultless, getting reading that were just background.
www.lazygranch.com...
I made a webpage of NTS leaks that reached free territory:
www.lazygranch.com...
Note the scale is mR/hr, not uR/hr. Even a few mR/hr, like you get from a hot rock, makes plenty of racket from the geiger counter. To read uR/hr, you
need a decent geiger counter, i.e. more sensitive than your typical civil defense model.