Impacts of point-source Net Alkaline Mine Drainage (NAMD) on stream macroinvertebrate communities.

Over 4000 km of Pennsylvania's flowing waters and attendant ecosystems have been degraded by mine drainage to the exclusion of multiple designated uses. Both Acid Mine Drainage (AMD) and Net Alkaline Mine Drainage (NAMD) may result from coal extraction depending on the underlying geology. Acid Mine Drainage is characterized as an acidic mixture of toxic heavy metals in solution, while NAMD is circumneutral in pH with metals forming oxidized precipitates.