USEPA approved the redesignation of the Milwaukee-Racine area to attainment with respect to the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS) (84 ppb) effective July 31, 2012. The Milwaukee-Racine former nonattainment area included the counties of Kenosha, Milwaukee, Ozaukee, Racine, Washington and Waukesha. The Wisconsin Department of Natural Resources (WDNR) submitted a redesignation request for the Milwaukee-Racine and Sheboygan areas from nonattainment to attainment with respect to the 1997 standard in September 2009 (with a supplement submitted November 2011). USEPA's redesignation effective July 31, 2012 did not take action on the Sheboygan redesignation due to preliminary 2012 ozone monitoring data indicating violations of the 1997 standard. The redesignation means that fewer sources in Wisconsin will be subject to the more stringent permitting requirements of nonattainment new source review. The regulations put in place to achieve compliance with the 1997 standard such as the nitrogen oxide (NOx) and volatile organic compound (VOC) reasonably available control technology (RACT) rules, vehicle inspection and maintenance program and reformulated gasoline standards remain in place. WDNR has published a fact sheet summarizing permitting requirements various counties in Wisconsin are now subject to based on this redesignation.

On May 31, 2012, USEPA also announced that Sheboygan County and a portion of Kenosha County were being classified as marginal nonattainment for the 2008 8-hour ozone NAAQS (75 ppb). The primary method of achieving compliance with these standards will be through federal programs such as a transport rule (i.e., Cross State Air Pollution Rule (CSAPR) or replacement for CSAPR) and vehicle standards. As noted in Trinity's August eNews, the CSAPR was vacated on August 21, 2012 and the Clean Air Interstate Rule (CAIR) is in place in the interim, pending a valid replacement. WDNR is following the developments of the transport rule to determine if any additional actions at the state level are required.