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Ozone 8-Hour

Most Recent Action

The EPA’s Office of Air Quality Planning and Standards is making available for public comment two draft assessment documents that describe the quantitative analyses the EPA is conducting as part of the review of the national ambient air quality standards (NAAQS) for ozone (O3):

 

Citing data from the state of Illinois, the EPA has revised its proposed designation for Kenosha County, and designated parts of the county nonattainment for the 2008 8-hour ozone standard. June 2012.

The EPA has announced that air quality for six southeastern Wisconsin counties – Kenosha, Milwaukee, Ozaukee, Racine, Washington and Waukesha – has improved enough to change the area’s status from nonattainment to attainment. This action formally recognizes that the area has now met the 1997 federal air quality standard of 84 parts per billion for ground-level ozone. July 2012.

 

Background

Section 109 of the Clean Air Act requires the EPA to establish National Ambient Air Quality Standards (NAAQS) for several types of air pollutants. Using this authority, EPA has created standards for six air pollutants: sulfur dioxide (SO2), particulate matter (PM2.5), nitrogen dioxide (NO2), carbon monoxide (CO), ozone, and lead.

In 1997, EPA set the 8-hour ozone standard at 80 parts per billion (ppb). In 2008, EPA created a new 8-hour standard, lowering it from 80 ppb to 75 ppb. Despite the new 2008 rule, the 1997 84 ppb designations remain in effect.

After issuing the new 2008 standards, the EPA in January 2010 proposed a new ozone standard in a range of 60 to 70 ppb. On September 2, 2011 President Obama asked the EPA to withdraw its proposed ozone standard revision.

This rule is part of a group of rules known as the EPA’s Regulatory Train Wreck.

 

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 primary and secondary National Ambient Air Quality Standards (NAAQS).

 

Standard

Current Revision:

The EPA is working on a revision to be released in 2013.

The EPA’s Office of Air Quality Planning and Standards is making available for public comment two draft assessment documents that describe the quantitative analyses the EPA is conducting as part of the review of the national ambient air quality standards (NAAQS) for ozone (O3):

On September 2, 2011 President Obama asked the EPA to withdraw its proposed ozone standard revision.

On December 8, 2010, the EPA said it will delay issuing revised air quality standards for ozone until July 2011 so that it can consider further recommendations from a panel of scientific advisers. On July 26, 2011 the EPA announced that the rule will not be released as intended in July 2011, but will be available “shortly.”

Proposed Rule (lowering from 75 ppb to between 60 ppb and 70 ppb) – Jan. 19, 2010.

Fact Sheet – Revisions to Ozone Standards.

2008 Standard:

40 CFR Part 50 & 58 – National Ambient Air Quality Standards for Ozone; Lowered Standard from 84 ppb to 75 ppb; Final Rule – March 27, 2008

Counties Violating the 2008 Ground-Level Ozone Standard (75 ppb).

EPA Fact Sheet – Final Revisions to the National Ambient Air Quality Standards for Ozone (New 2008 Standard (promulgating a new 8-hour standard (75 ppb)).

1997 Standard:

40 CFR Part 50 – National Ambient Air Quality Standards for Ozone; Final Rule: July 18, 1997. Federal Register notice revising the previous ozone (1-hour) standard, and promulgating a new (8-hour) standard (84 ppb).

American Trucking Associations, Inc., et al., v. Environmental Protection Agency: Decided March 26, 2001. D.C. District Court ruling affirming EPA’s revised (1997) standards for ozone (8-hour) and particulate matter (PM2.5, issued same day as ozone).

 

Designation

2008 8-hour Ozone Standard (75 ppb)

WDNR – 2008 Daily Ozone — Standard Nonattainment Designation Option Technical Support Document; Feb. 27, 2009

Gov. Jim Doyle Letter to EPA: Recommending All Wisconsin Counties be Designated as Attainment for the 8-Hour Ozone Standard; March 12, 2009.

On September 2, 2011 President Obama asked the EPA to withdraw its proposed ozone standard revision.

The EPA released a memo announcing that it would begin implementing the 2008 8-hour ozone standard. The Sheboygan area is listed as a marginal nonattainment area in the EPA’s potential classification table. September 22, 2011.

On December 12, 2011 the EPA filed a proposed consent decree with the environmental organization WildEarth Guardians concerning deadlines for implementing the 2008 ozone NAAQS. Under the consent decree, the EPA would agree to make final non-attainment determinations by May 31, 2012.

December 2011 – The EPA intends to designate 43 areas as being in nonattainment of the 2008 ozone standard, including Sheboygan County, Wisconsin. The EPA also indicated that it would be reevaluating its designation of Kenosha County as attainment based on 2011 air quality data recently submitted by Illinois. The State of Wisconsin has until February 29, 2012 to submit additional information to the EPA in support of designating Sheboygan County as attainment.

On December 7, 2011, Illinois sent its 2011 certified air quality data to the EPA for consideration in the ozone designation process. The 2011 ozone data indicates a monitored violation of the 2008 ozone standard at the Zion monitor in Lake County, Illinois, which is part of the Combined Statistical Area (CSA) that includes Chicago and Kenosha County, Wisconsin.

Because the data indicates an ozone level violation, the EPA announced on January 31, 2012 that intends to designate the Chicago-Naperville, Illinois-Indiana-Wisconsin area as nonattainment, with boundaries that include: Kenosha County in Wisconsin; Lake, Porter, and Jasper Counties in Indiana; and several counties in Illinois.

The technical support document provides the technical and qualitative bases for the intended boundaries of the Chicago-Naperville, IL-IN-WI ozone nonattainment area. Kenosha County has not been a part of the Chicago nonattainment area in the past. The county was instead included in the Milwaukee-Racine, Wisconsin ozone nonattainment area for the 1997 ozone standard, which the EPA has proposed to designate as attainment for the 2008 standard.

The VOC and NOx emissions in Kenosha County, precursors to ozone pollution, are relatively low and similar to those for counties recommended for exclusion from the intended ozone nonattainment area. In addition, it is noted that Illinois’ and Wisconsin’s wind direction analyses for high ozone days indicate that Kenosha County emissions are probably downwind of the violating Zion, Illinois monitor on high ozone days. These conclusions would support the exclusion of Kenosha County from the intended ozone nonattainment area.

However, the EPA thinks that it is appropriate to include it in the Chicago nonattainment area now because historically the Chiwaukee Prairie monitoring site in Kenosha County, Wisconsin has been the high downwind monitoring site for the Chicago region. The Chiwaukee Prairie ozone design value was used to establish the classification for the Chicago-Gary-Lake County, IL-IN ozone nonattainment area under both the 1997 8-hour ozone standard and the 1-hour ozone standard. In addition, monitoring data from this monitoring site was historically used by the States of Illinois, Indiana, and Wisconsin in conjunction with modeled ozone concentrations to demonstrate that emission reductions in the Chicago area were sufficient to attain the 1-hour ozone standard and the 1997 8-hour ozone standard.

The EPA determined that 45 areas across the country, including Sheboygan County, are not meeting the 2008 8-hour ozone standards based on the most recent certified air quality data. Sheboygan County barely exceeded the 75ppb standard, so it will be designated as a marginal nonattainment area, which is the lowest of six nonattainment classifications and carries the fewest regulatory requirements.

On June 11, 2012, citing data from the state of Illinois, the EPA revised its proposed designation for Kenosha County, and designated parts of the county nonattainment for the 2008 8-hour ozone standard.

Related Documents:

  • Final Area Designations for the Chicago Metropolitan Area (Including Kenosha County)

Overview Q and A

Map of Final Designations for 2008 Ozone Standards

Nonattainment Designations for the 2008 Ozone Standards – Counties by State, May 2012

Federal Register Notice Detailing Boundaries for Area Designations, June 11, 2012

Response to Significant Comments, May 2012 Addendum

Final Area Technical Support Documents

  • Designations (Including Sheboygan County)

Final Classifications Rule, April 30, 2012

Federal Register Notice Detailing Boundaries for Area Designations, May 2012

Fact Sheet Summarizing Final Classifications Rule

Overview Q and A, May 2012

Map of Final Designations for 2008 Ozone Standards, May 2012

Nonattainment Designations for the 2008 Ozone Standards – Counties by State, May 31, 2012

Menu of Control Measures

  • Correspondence between Wisconsin and the EPA

Letter from Gov. Doyle recommending all counties in Wisconsin be designated as attainment for the 8-hour ozone standard, March 2009

Letter from the EPA notifying Wisconsin that it will begin the designation process for the 2008 standard(indicating Sheboygan county will be designated nonattainment), December 9, 2011

EPA’s original technical support document, December 2011

Letter from the EPA notifying Wisconsin that it may also designate Kenosha County as nonattainment, January 31, 2012

EPA’s revised technical support document, January 2012

DNR’s response to the proposed Sheboygan designation, February 29, 2012

DNR’s response to the proposed Kenosha designation, April 20, 2012

Gov. Walker’s response to the proposed Kenosha designation, April 24, 2012

 

 

1997 8-hour Ozone Standard (84 ppb)

In July 2012 the EPA

announced

that air quality for six southeastern Wisconsin counties had improved enough to change the area’s status from nonattainment to attainment. This action formally recognizes that the area has now met the 1997 federal air quality standard for ground-level ozone.

The counties that now meet the 84 parts per billion 1997 standard – Kenosha, Milwaukee, Ozaukee, Racine, Washington and Waukesha – have been in a constant state of nonattainment for federal ozone standards since 1991 and were part of EPA’s “Milwaukee-Racine Nonattainment Area.”

The DNR submitted a redesignation request on September 11, 2009, and supplemented the submittal on November 16, 2011. These submittals also requested the redesignation of the Sheboygan area (Sheboygan County) to attainment for the 1997 8-hour ozone NAAQS.

The EPA proposed to approve the redesignation of both areas on February 9, 2012, and provided a 30-day review and comment period. The EPA received comments from the Sierra Club, Midwest Environmental Defense Center, and Wisconsin Manufacturers and Commerce.

The EPA is not taking final action on the Sheboygan redesignation request at this time because preliminary 2012 ozone monitoring data indicate that the area has violated the 1997 standard.

In addition to approving the redesignation of the Milwaukee-Racine area, the EPA is taking several other related actions. The EPA is approving, as a revision to the Wisconsin State Implementation Plan (SIP), the State’s plan for maintaining the 1997 8-hour ozone standard through 2022 in the Milwaukee-Racine area. The EPA is approving the 2005 emissions inventories for the Milwaukee-Racine and Sheboygan areas as meeting the comprehensive emissions inventory requirement of the Clean Air Act. Finally, the EPA finds adequate and is approving the State’s 2015 and 2022 Motor Vehicle Emission Budgets (MVEBs) for the Milwaukee-Racine area.

WDNR – Attainment Demonstration – The Wisconsin Counties of Kenosha, Racine, Milwaukee, Waukesha, Ozaukee, Washington, Sheboygan, Manitowoc, and Door – From Nonattainment to Attainment of the 1997 8-Hour Ozone NAAQS; Revision to Wisconsin’s Ozone Air Quality Management State Implementation Plan, Sept. 2009.

WDNR – Revisions to the State Implementation Plan for 8-Hour Ozone, June 2007

 

Additional Information

The EPA’s Ozone Website

The DNR’s Ozone Website

Summary and Critique of the Benefits Estimates in the RIA for the Ozone NAAQS Reconsideration, NERA Report, July 2011

EPA Guidance on the Use of Models and other Analyses for Demonstrating Attainment of Air Quality Goals for Ozone, PM2.5, and Regional Haze; April 2007

Potential Economic Impacts of a Stricter Ozone Standard: NAM, July 2014.