8-Hour Ozone Nonattainment Boundary Recommendations

The following links provide reference to the 8-Hour Ozone Nonattainment Boundary Recommendation packages that North Carolina submitted to the U.S. Environmental Protection Agency (EPA) on March 12, 2009, October 28, 2011, and February 29, 2012. These packages are in response to a Clean Air Act requirement for states to submit to EPA its recommendations for nonattainment designations within 1-year of promulgation of a new or revised National Ambient Air Quality Standard (NAAQS). The 8-Hour Ozone NAAQS was revised to 0.075 parts per million (ppm) on March 12, 2008. Please direct further questions concerning this package to Sushma Masemore at Sushma.Masemore@ncdenr.gov.

March 12, 2009 Submittal

October 28, 2011 Submittal

In September 2009, the EPA announced that they were going to reconsider the 2008 ozone standard and postponed implementation of this standard. It was announced that the reconsideration of the 2008 ozone standard would be withdrawn on September 2, 2011. The EPA is now moving forward with the implementation of the 2008 ozone standard and the EPA requested states wishing to revise their boundary recommendations to submit the revisions by October 28, 2011. The EPA also agreed to use 2009-2011 ambient air quality data for the designation process if a state planned to certify their 2011 data early. North Carolina has elected to certify the 2011 ambient air quality data early and has made its revised boundary recommendations based on the 2009-2011 data.

The revised boundary recommendation submitted to the EPA can be found at the following links:

February 29, 2012 Submittal

On December 8, 2011, the EPA sent North Carolina their response to the ozone boundary recommendation submitted on October 28, 2011. The EPA stated that they intend to support North Carolina's recommended area designations and boundaries for all areas including the Charlotte-Gastonia-Salisbury nonattainment area. The EPA also stated that they would work with the State regarding the appropriate boundary for the Charlotte-Gastonia-Salisbury nonattainment area. EPA requested that any additional information regarding the appropriate nonattainment boundary should be submitted by February 29, 2012. North Carolina evaluated the factors EPA plans to consider in determining nonattainment area boundaries, as outlined in their 2008 boundary guidance, for the Charlotte-Gastonia-Salisbury area and developed an amended boundary recommendation.

The amended boundary recommendation submitted to the EPA on February 29, 2012, can be found at the links below: