On May 1, 2012 EPA announced its final designations under the 2008 ozone standard and has agreed with NC's recommended nonattainment designations and identified only the Charlotte area in NC as in "marginal" nonattainment.

In February 2012, NC recommended that EPA designate the exisiting nonattainment boundary for the 1997 ozone standard in the Charlotte area minus some townships in Lincoln, Gaston, Union, Cabarrus and Rowan Counties. EPA has agreed to designate those areas in marginal nonattainment with the 2008 ozone standard.

EPA's action sets a three year attainment deadline from the effective date (December 31, 2012) to show attainment, which would give the area until December 31, 2015.