There are quite a few different ways that mining can cause groundwater pollution.
Read more about groundwater pollution and mining at the following locations:
- http://en.wikipedia.org/wiki/Acid_mine_drainage When the sulfides in coal is exposed during the mining process, the water reacts with it, dramatically lowering the pH of the water.
- http://www.prenterwaterfund.org/ details the impacts of coal slurry operations on the town of Prenter, West Virginia. It has a very good description of the different kinds of mining operations that effect groundwater, as well as a list of some of the chemicals used in slurry operations that have migrated to the private wells in Prenter.
- http://www.appvoices.org/index.php?/frontporch/blogposts/app_voices_joins_forces_with_rawl_residents_for_waterline/ details the effects of water contaminated by coal mining on the residents of Rawl, Sprigg, Merrimac and Lick Creek, West Virginia.