This is the only road to and from the REPCONN test site, and is teeming with feral ghouls. Be on your guard, and check the checkpoint for chems on the small table, then ransack the checkpoint under the bridge itself. Then run to the sandbag defences at the far (south-west) end, under the bridge, to collect a number of items. Finally, double back up the north slope of the bridge to the top of the bridge itself and claim further items. There are also several ash piles containing rebar clubs.
REPCONN test site checkpoint appears only in Fallout: New Vegas.