FILE - This June 3, 2003 file photo shows the Kennecott copper mine, the largest open pit mine in the world, in Bingham Canyon, Utah. Doctors and a lobby group of Utah mothers are blaming the mine's operator for contributing one-third of Salt Lake County’s pollution. They have filed a lawsuit against Kennecott Utah Copper, accusing it of violating the U.S. Clean Air Act. The company operates with the consent of state regulators who enforce the federal law. (AP Photo/Douglas C. Pizac, File)