Phelps Dodge operates this large, open pit copper mine and processing facility, currently the largest copper mine in North America (measured in total output -- Kennecott's Bingham Pit in Utah is larger in size). The mine has produced over 1 billion pounds of copper annually in some recent years. The Morenci Complex consists of three adjacent open pits and associated refining plants.
Some photos and more info.
[url]http://www.mining-technology.com/projects/morenci/[/url] />