Read "coal and the environment." what resource is often compromised due to mining?

Water is often compromised through mining. Mining often leads to water pollution. For example, acid mine drainage occurs when rising water levels in mines come into contact with sulfide-containing rocks. This leads to a chemical reaction which produces sulfuric acid. The water produced is very acidic, and is able to dissolve all sorts of toxic metals from the rocks. This water can enter the surface waters such as lakes and rivers, and the low pH of the water as well as the toxicants can destroy the aquatic ecology. 

The correct answer is c.

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