Surface Mining Impacts on Physical, Biological, and Chemical Variables in the Upper Big Sandy River Drainage

Surface coal mining is known to alter biological, physical, and chemical compositions of aquatic ecosystems, though in Appalachian streams the most well documented effects are due to acid mine drainage and mountain top removal/valley fill in headwater streams. We were interested in the effects of current and past mining activities in understudied streams of the Big Sandy River drainage where acidification is uncommon due to underlying geological chemical composition. We sampled fish, water quality, and physical habitat at 35 sites throughout the Virginia portion of the Big Sandy River drainage, a region of intense coal mining. We used multivariate methods to explore responses of stream attributes to historical and current mining intensity, indexed by total extent of surface mining permits in 1979 and 2011. Salinity, conductivity, fine silt deposition, and substrate embeddedness increased with increased mining. Salinity (0.3 - 0.8 ppt) and conductivity levels (328-1313 μS) positively correlated with mining impacts at most sites. Multivariate analyses indicated conductivity and watershed size are important drivers of site-level fish species richness. Richness across sites was generally low and decreased with increasing conductivity and smaller watershed sizes. These watersheds are highly impacted by long-term surface mining, which will continue for decades with the large coal reserves in this area.