Check out this article regarding the contamination of the water supply for several communities by an old, illegal mining operation.
After suffering years of contamination, locals finally sued Pegasus Gold under the Clean Water Act and came away with a $36 million settlement in 1996. However, that doesn’t go far when water has to be treated in perpetuity. The water sources for Fort Belknap are still threatened by acid mine drainage, but currently the tribes’ funding for water treatment lasts only until 2028.