Court vacates Cincinnati's PM-2.5 attainment

摘要

In a ruling that will not give comfort to state governments attempting to bring areas into attainment with the 1997 National Ambient Air Quality Standards (NAAQS) for particulate matter (PM)-2.5, a three-judge panel of the U.S. Court of Appeals for the 6th Circuit vacated U.S. EPA's attainment redesignation of the Ohio and Indiana portions of the Cincinnati-Hamilton area because the PM-2.5 state implementation plans (SIPs) used by those states did not impose reasonably available control measures or technology (RACM/RACT) (Sierra Club v. EPA).