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Sulfur Dioxide in Douglas, Arizona

December 27, 2005: Approval of Arizona's Plan to Meet the Sulfur Dioxide Air Quality Standards in the Douglas Area

EPA has signed a direct final rule approving Arizona's plan to maintain attainment of the short-term (24-hour) and long-term (annual) primary National Ambient Air Quality Standards (NAAQS) for sulfur dioxide (SO2) in the Douglas area, as well as Arizona’s request to redesignate this area from nonattainment to attainment for SO2.

The Douglas area has not had a violation of either the annual or the 24-hour health-based standard since 1987. The primary source of sulfur dioxide pollution in the Douglas area was the Phelps Dodge Douglas Reduction Works smelter, which ceased operation in 1987 and was dismantled by 1991. There are currently no other SO2 sources of this magnitude in Douglas.

Related documents

Federal Register Notice (February 28, 2006)

Press Release

Contact information

Wienke Tax
Office of Air Planning
EPA Region 9
Email: tax.wienke@epa.gov
Phone: (520) 622-1622

Region 9 Topics and Programs | A-Z Index


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