Hydraulic Mine Pits of California

This dataset is a compilation of boundary location polygons for 167 hydraulic mine pits located in northern California. This dataset was compiled from three sources, Topographically Occurring Mine Symbols (TOMS) database produced by the California Department of Conservation (2001), Yeend (1974), and on-screen digitizing, using current (2015) satellite imagery, of additional hydraulic mine pits not contained in either of these sources. References Cited: California Department of Conservation, 2001, Topographic Occurring Mine Symbols: Office of Mine Reclamation, Abandoned Mined Lands Unit, accessed 02/2010 at http://www.conservation.ca.gov/omr/abandoned_mine_lands/toms/ Yeend Warren.E., 1974, Gold-bearing gravel of the ancestral Yuba [...]