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Miami | PM-10 Nonattainment Area

Counties Affected:

Parts of Pinal and Gila Counties  | View on a Map >

Nonattainment Area Designation Date:

Oct. 31, 1990
(55 FR 45799)

Classification Level: 


Pollutant of Concern:

PM10 (particulate matter 10 microns or less in diameter; 1987 standards)


The concentration of PM10 in the air in Miami has been below federal standards for several years. ADEQ is developing a redesignation request so that EPA will reclassify the area as an attainment area. As part of this request, ADEQ must include an updated emissions inventory, modeling demonstration and a strategy for Exceptional Events. Freeport-McMoran made numerous improvements to the Miami smelter as part of a $250 million expansion project that will further reduce PM10 concentrations. Some of the controls implemented at the copper smelter include:

  • Baghouses for materials storage bins
  • Baghouse for anode furnace
  • Wet electrostatic precipitator for furnace
  • Ventilation system over furnace
  • Water suppression for material piles and unpaved roads
  • Paved road cleaning

Sources of Pollutant:

  • Manufacturing of metal
  • Open burning and wildfires
  • Windblown dust

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