A settling CAA defendant responsible for violations at a copper-smelting facility in Hayden, Arizona, must pay a $4.5 million civil penalty; perform injunctive relief to reduce emissions of particulate matter, sulfur dioxide, and several hazardous air pollutants, including lead and arsenic; spend at least $8 million on environmental mitigation projects to benefit communities adversely affected by the pollution; and perform a $1 million supplemental environmental project to reduce the emissions.