Wired has published a collection of photos of open-pit mines seen from space, you can check it out over here.
Pictured below is the former copper mine Berkeley Pit in Butte, Montana. Copper was mined at this pit between 1955 and 1982, as well as some gold and silver. Today the 1,780-foot-deep mine is filled with about 900 feet of highly contaminated water that can be as acidic as battery acid. It contains arsenic, cadmium, pyrite, zinc, copper and sulfuric acid.