Approval of Arizona Air Plan Revisions, Arizona Department of Environmental Quality

The Environmental Protection Agency (EPA) is proposing to approve a revision to the Arizona Department of Environmental Quality (ADEQ) portion of the Arizona State Implementation Plan (SIP). This revision concerns emissions of lead-bearing fugitive dust from roads, storage piles and other activities associated with the primary copper smelter located in Hayden, Arizona. We are proposing to approve a state rule and associated appendix to regulate these emissions under the Clean Air Act (CAA or the Act). We are taking comments on this proposal and plan to follow with a final action.