Ozone Designations Regulatory Actions
This page contains a chronological listing of all regulatory actions related to designations for the 2015 ozone standards.
June 30, 2023 - Court Reverses 2021 El Paso County, TX Nonattainment Area Designation for the 2015 ozone NAAQS
In November 2021, EPA created a multistate nonattainment area encompassing the existing Sunland Park, NM nonattainment area and the newly designated El Paso, TX nonattainment area. Texas petitioned the court claiming that El Paso’s designation was impermissibly retroactive. On June 30, 2023, the D.C. Circuit Court issued a decision reversing the Agency’s multistate nonattainment area designation. As a result of the Court’s decision, Sunland Park, NM retains its prior nonattainment area status and El Paso, TX reverts back to its prior attainment designation. EPA is reviewing the Court’s decision to determine the appropriate next steps.
November 17, 2021 - EPA is completing its response to the D.C. Circuit Court’s remand of certain air quality designations for the 2015 Ozone National Air Quality Standards by expanding its initial designations for the Doña Ana County (Sunland Park Area), New Mexico and Denver Metro/North Front Range, Colorado nonattainment areas. Read the November 2021 final notice and supporting documents.
May 26, 2021 - EPA takes action on its review of certain area designations for the 2015 ozone standards in response to a July 2020, remand issued by the District of Columbia Circuit Court. Learn more about the May 2021 action.
April 14, 2020 - EPA has denied a petition for reconsideration and stay request relating to the Agency’s action to designate the Uinta Basin, Utah as nonattainment for the 2015 ozone standards. Learn more about the April 2020 action.
October 4, 2018 - EPA corrected errors in the regulatory text regarding the designation of certain areas for the 2015 ozone standards. Learn more about the October 2018 action.
July 17, 2018 - EPA completed designations for the San Antonio, Texas metropolitan area. Learn more about the July 2018 action.
April 30, 2018 - EPA completed additional area designations for the 2015 ozone standards. Learn more about the April 2018 action.
March 19, 2018 - EPA responds to Texas recommendations for the San Antonio Area. Learn more about the March 2018 action.
December 22, 2017 - EPA responds to state and tribal recommendations by indicating the anticipated area designations for most remaining portions of the U.S. Learn more about the December 2017 action.
November 6, 2017 – Consistent with the states’ and tribes’ recommendations, EPA designates most of the U.S. “attainment/unclassifiable” for the 2015 ozone standards. Learn more about the November 2017 action.
August 2, 2017 -Withdrawal of Extension of Deadline for Promulgating Designations for the 2015 Ozone National Ambient Air Quality Standards. Read the Withdrawal of Extension Notice (pdf) (199 KB).
June 6, 2017 - The Administrator has determined that there is insufficient information to complete area designations for the 2015 ozone standards and is extending the deadline by one year, until October 1, 2018. Learn more about the June 2017 action.