A new report shows existing U.S. hardrock mines (e.g. gold, copper, uranium) will pollute up to 27 billion gallons of fresh water per year, and cost as much as $67 billion per year to clean, in perpetuity.
Based on government data, ‘Polluting the Future: How mining companies our polluting the nation’s waters in perpetuity’ also reveals that four proposed mines could annually pollute an additional 16 billion gallons.
And that is just in the USA…
See http://www.minesandcommunities.org/article.php?a=12276&l=1.