Supreme Court won't hear challenge to EPA pollution rule

The Supreme Court on Tuesday rejected a major copper company's plea to review an Environmental Protection Agency air pollution rule that set standards for sulfur dioxide, a pollutant tied to several respiratory ailments.The justices denied Asarco LLC's request to review an appellate court decision that upheld EPA's 2010 regulation, which had drawn challenges from several states, companies and industry groups.Asarco, which operates a major copper smelter in Arizona, in October asked the high court to review whether EPA illegally set a standard - 75 parts per billion over one hour - that it calls overly stringent.The company had alleged that the U.S. Court of Appeals for the District of Columbia Circuit failed to properly restrain EPA's discretion in setting the exposure standard for SO2.