It's an odd sight

Northeast of Beale Air Force Base, Marysville, California-click to enlarge

  When I was flying as a crewmember in Fleet Tactical Support Squadron Thirty from the Naval Air Station in Alameda, California there were a few times, mostly on training flights, that we would use Beale AFB to do instrument approaches, or come close to landing, go up higher and approach again, repeat about 20 times.  It's boring for an observer up there (most of the time) watching for other aircraft.  I was always fascinated by the "mine tailing's" you can see in the upper middle (left) to top (right) in that satellite image up there from Google Maps.  From that high up you can see the pattern of the dredge as it went back and forth.  Tailing's are the rocks left over after the ore is separated (gold in this case), they're just left there.  These particular piles have covered two whole "temporary" towns, Marigold and Hammondon, that were developed for miners and their families.
  This particular dredge worked the Yuba and Feather Rivers for quite a few years, there are now museums, and a dredge in Marysville for people to check out.  I was never "on the ground" there but it would be interesting to see from eye level.  Ah!  The joys of flying!  I even got paid for sightseeing, what a deal.

A dredge at work, see the rock piles, they're all around it.

A photo from www.appealdemocrat.com, shows a boy picking over rocks, the dredge is still there,
in Marysville.  The Appeal-Democrat is the newspaper for Yuba and Sutter Counties, California