On a Lead Removal project at Lordship Point, Connecticut. 
(The former site of a Gun club)

Trimble Total Station 4700 GPS instrument shown over a known point.  The radio is used to broadcast real-time GPS information for correctional purposes to the "Rover" station.  Real Time Kinematic differential correction can produce location measurements with better than one cm accuracy.  The Rover station is shown above with its optional legs in place in-between the radio and the stationary GPS station.

A relatively high resolution aerial photo of the site showing the lead separation plant is available on the www (565 KB).