Rio Tinto (www.riotinto.com)

Kennecott Minerals (www.kennecottminerals.com)

National Mining Association (www.nma.org)

Mineral Information Institute (www.mii.org)

Michigan Department of Environmental Quality (www.michigan.gov/deq)

Flambeau Mine, Wisconsin (www.flambeaumine.com)

Ridgeway Mine, South Carolina (http://kennecottminerals.com/mines/ridgeway.html)

Greens Creek Mine, Alaska (http://kennecottminerals.com/mines/greens.html)