Weaverville, California was home to a lot of gold miners back in the day, as the fast flowing rivers and streams of the gold-rich Trinity Alps gave up their bounty. More agressive mining techniques were used here at the stream behind the stamp mill, where "hydraulicking" water canons blasted aways tons of soil to uncover a the tiny flecks of gold dust that were then extracted via sluices.
Read more about the California Gold Rush at Online Highways.