It's not just burning coal—extracting it pollutes water, too. Fracking uses a mix of 750 chemicals, including some known to be toxic, to pry open underground cracks in order to extract natural gas. If not carefully discarded, this wastewater can be hazardous. In Appalachia, mining companies literally blow apart mountaintops to reach coal deposits. It's as destructive as it sounds, and the exposed rock leaches chemicals like selenium and sulfate into nearby waters. Though it didn't find a causal link between these practices and health impacts, a 2015 review concluded that "people who live near coal mining in Appalachia experience a wide range of health problems," including "forms of cancer, cardiovascular and respiratory disease, kidney disease, developmental problems, depression, poorer health-related quality of life, and a wide variety of illness symptoms."