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EPA Finalizes Last 2015 Ozone Designations for 8 Counties in Texas

This Action Completes Designations Process for 2015 Ozone Standard

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WASHINGTON  — On July 17, 2018, the U.S. Environmental Protection Agency (EPA) completed area designations for the 2015 ozone standards by designating eight counties in the San Antonio, Texas metropolitan area. EPA has designated seven of the eight counties in the San Antonio area, including Atascosa, Bandera, Comal, Guadalupe, Kendall, Medina, and Wilson, as attainment/unclassifiable for the 2015 standard. Based on data from EPA-approved air quality monitors, EPA has designated Bexar County as nonattainment. These designations will take effect 60 days after the notice summarizing this action is published in the Federal Register.

“We look forward to supporting Texas as they work to improve air quality and foster economic opportunity,” said Acting Administrator Andrew Wheeler. “Information provided by the state indicates that the San Antonio area is on the path toward attainment, and we expect Bexar County will be able to demonstrate that it meets the standard well in advance of the attainment date in 2021. Analysis from Texas about the role of international emissions, including from Mexico, and the pending closure of a coal-fired power plant in Bexar County will help ensure that implementation of this standard has minimal burdens on economic development.”

Overall, the U.S. has experienced dramatic progress for ozone and other air pollutants and we expect these trends to continue in San Antonio and Texas. Compared to designations issued in 2012 for the 2008 standards, there are more than 10 percent fewer counties being designated “nonattainment” for the more stringent 2015 standard. National average ozone concentrations dropped by 13 percent from 2007 to 2016, and its precursor emissions have also plummeted over the last decade (U.S. emissions of volatile organic compounds dropped by more than 15 percent from 2007 to 2017, and nitrogen oxide emissions were down 40 percent over the same period).

EPA has developed and will be announcing a number of tools to minimize disruption for nonattainment areas and facilitate demonstrations that these areas meet the standard by the attainment dates:

  • Later this year, EPA will finalize its implementation and state plan requirements rule for the 2015 ozone standard. Consistent with the President’s April 2018 memorandum on Promoting Domestic Manufacturing and Job Creation—Policies and Procedures Relating to Implementation of Air Quality Standards, we anticipate that this rule will facilitate flexible regulatory tools to address permitting requirements and international emissions in these areas.

  • Pursuant to Section 319B of the Clean Air Act, EPA is releasing and communicating a number of tools related to the exclusion of data for “exceptional events” outside the control of state, local, or tribal air agencies. Since 2016, EPA has acted upon more than 20 “exceptional event” demonstrations, nearly all of which concurred with state recommendations and thus provided the state with regulatory relief.

  • The Agency also acknowledges the role played by background and international ozone concentrations that are outside the control of state and tribal air agencies. EPA is committed to maximizing flexibility for other tools for regulatory relief, including Clean Air Act provisions to address emissions caused by international sources.

  • As outlined in the Agency’s FY2018-2022 Strategic Plan and elsewhere, EPA is committed to timely processing of preconstruction permits, state implementation plans, and other relevant demonstrations.


The Clean Air Act directs that ozone nonattainment areas will be classified based on the severity of the air quality problem at the time of designation. The Bexar County nonattainment area is classified as a “Marginal” nonattainment area. Marginal nonattainment areas are those closest to meeting the standard and, as a result, have few mandatory planning and control requirements. These areas are expected to attain the standard as quickly as possible but no later than three years after this designation becomes effective.

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