Ozone 1-Hour

Background

On June 15, 2005, the EPA revoked the 1-hour ambient air quality standard for ozone for all areas of the nation, except the 8-hour ozone nonattainment Early Action Compact Areas. The EPA retained the former 1-hour ozone designations and classifications as of June 15, 2004 in subpart C of 40 CFR Part 81 solely for purposes of the anti-backsliding provisions of 40 CFR 51.905. In a series of federal circuit court cases, the EPA was directed to expand the scope of the anti-backsliding provisions in Section 172(e) of the CAA [42 USC 7502(e)] that applied to areas not meeting the 1-hour standard.

In Wisconsin, based on 2003 through 2005 monitoring data, the Milwaukee-Racine ozone nonattainment area again attained the 1-hour ozone standard, two years ahead of mandated 2007 attainment date. The area continues to measure attainment of the 1-hour ozone standard.

The DNR redesignated Milwaukee-Racine nonattainment area (Kenosha, Milwaukee, Racine, Ozaukee, Washington and Waukesha Counties) to attainment of the 1-hour standard under state law. (See below under “Implementation/Conformity).

Authority

42 USC Sec. 7409 (CAA) – National Primary and Secondary Ambient Air Quality Standards: December  31, 1970. This section of the CAA provides the EPA authority to promulgate National Ambient Air Quality Standards (Primary and Secondary) or, NAAQS.

Implementation/Conformity

WDNR – Redesignation of Kenosha, Milwaukee, Ozaukee, Racine, Washington, and Waukesha from nonattainment to attainment of the 1-hour standard; February 10, 2009.

WDNR — Analysis Demonstrating Attainment of the 1-Hour Ozone National Ambient Air Quality Standards (NAAQS) for the Milwaukee-Racine Severe Ozone Nonattainment Area; Nov. 25, 2008.

40 CFR Part 52 – Approval and Promulgation of Implementation Plans; Wisconsin; July 2, 2002.

40 CFR Part 52 – Approval and Promulgation of Air Quality Plans; Wisconsin; Post-1996 Rate of Progress Plan for the Milwaukee-Racine Ozone Nonattainment Area; June 22, 2001.

WDNR – Wisconsin’s 2000 SIP Submittal: “Attainment Demonstration for Ozone for the Year 2007: The Phase 3 Attainment State Implementation Plan for the Eastern Wisconsin Nonattainment Areas”; Dec. 22, 2000.

40 CFR Part 52 – Approval and Promulgation of Implementation Plans; Wisconsin; Ozone; July 2, 2001.

40 CFR Part 52 – Approval and Promulgation of Implementation Plans; Wisconsin; June 20, 2003.

Applicability

40 CFR Part 81 – Identification of Ozone Areas Attaining the 1-Hour Standard and to Which the 1-Hour Standard Is No Longer Applicable; Direct Final Rule: January 16, 1998.

40 CFR Part 81 – Identification of Ozone Areas Attaining the 1-Hour Standard and to Which the 1-Hour Standard Is No Longer Applicable; Final Rule: June 5, 1998.

40 CFR Part 81 – Identification of Additional Ozone Areas Attaining the 1-Hour Standard and to Which the 1-Hour Standard is No Longer Applicable; Final Rule: July 22, 1998.

40 CFR Part 81 – Identification of Additional Ozone Areas Attaining the 1-Hour Standard and to Which the 1-Hour Standard is No Longer Applicable; Final Rule: June 9, 1999.

40 CFR Part 50 – Recinding Findings that the 1-Hour Ozone Standard No Longer Applies in Certain Areas: October 25, 1999.

40 CFR Part 50 – Stay of Authority Under 40 CFR Part 50.9(b) Related to Applicability of 1-Hour Ozone Standard; Proposed Rule: December 27, 2002.

40 CFR Part 50 – Stay of Authority Under 40 CFR Part 50.9(b) Related to Applicability of 1-Hour Ozone Standard; Final Rule: June 26, 2003.

Data

EPA – Recent Design Values for Counties Predicted by Regional Ozone Modeling to Have 1-Hour Ozone Exceedences in 2007 Without Tier 2/Sulfer Control: September 28, 1999.

Health and Environmental Affects

EPA – Health and Environmental Effects of Ground-Level Ozone: July 17, 1997.

Voluntary Reduction

NR 437 – Voluntary Emission Reduction Registry Rule (state rule): Effective November 1, 2002.

EPA – Schedule for 8-Hour Ozone Designations and its Effect on Early Action Compacts: November 14, 2002.