From 1969 thru 1992 l worked about 3 months out of very year, just over the hill from Area 51 in areas 12 and 19. Even with a TS clearance, we could never get close to it. I added it all up and I spent a little over 13 years living on the Nevada Test Site. Ground sensors are installed all around. As Hemiallen said , some of the response teams are modified dune buggies, but they have dual 30 cals on them, not 50 cals ,at least the ones I encountered.
No one will get close to Area 51
If you get on Google Earth and search for Mercury, Nevada, Go north about 30 miles until you see Sudan Crater ( biggest one out there), Area 51 is north of that ,maybe -20-15 miles
