TechGen Metals (ASX:TG1) has kicked off an electromag geophys helicopter survey on-site its Sally Downs play, a copper project. Located in the WA’s Kimberley region, TechGen was quick to point out on Monday that it’s only 10km south of the existing Savannah ni-cu-co mine. Whether that proximity actually means anything for investors remains to be seen. The project acreage is located over the Halls Creek Orogen; this will be the first ever airborne geophys survey onsite. Drill targets are the name of the game. “Upon completion of the survey, the data will be modelled by Expert Geophysics and Sou…