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Extension of Deadline for Promulgating Designations for the 2015 Ozone National Ambient Air Quality Standards

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Environmental Protection Agency (EPA).


Extension of deadline for promulgating designations.


The Environmental Protection Agency (EPA) is announcing that it is using its authority under the Clean Air Act (CAA) to extend by 1 year the deadline for promulgating initial area designations for the ozone national ambient air quality standards (NAAQS) that were promulgated in October 2015. The new deadline is October 1, 2018.


The deadline for the EPA to promulgate initial designations for the 2015 ozone NAAQS is October 1, 2018.

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For questions regarding this action, contact Denise Scott, Air Quality Planning Division, Office of Air Quality Planning and Standards, Mail Code C539-04, Environmental Protection Agency, Research Triangle Park, North Carolina 27711; telephone number: (919) 541-4208; email address:

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I. General Information

A. Does this action apply to me?

Entities potentially affected by this action include state, local and tribal governments that would participate in the initial area designation process for the 2015 ozone standards.

B. Where can I get a copy of this document and other related information?

The EPA has established a docket for designations for the 2015 ozone NAAQS under Docket ID No. EPA-HQ-OAR-2017-0223. All documents in the docket are listed in the index. Although listed in the index, some information is not publicly available, e.g., confidential business information or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, will be publicly available only in hard copy. Publicly available docket materials are available either electronically in or in hard copy at the EPA Docket Center EPA/DC, EPA West, Room 3334, 1301 Constitution Avenue NW., Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the EPA Docket Center is (202) 566-1742.

An electronic copy of this notice is also available at​ozone-designations along with other information related to designations for the 2015 ozone NAAQS.

II. Designations Requirements

On October 1, 2015, the EPA signed a notice of final rulemaking that revised the 8-hour primary and secondary ozone NAAQS (80 FR 65292; October 26, 2015). The primary standard was lowered from 0.075 parts per million (ppm) to a level of 0.070 ppm. The EPA also revised the secondary standard by making it identical in all respects to the revised primary standard. (The previous ozone NAAQS were set in 2008 and remain effective.)

After the EPA establishes or revises a NAAQS pursuant to CAA section 109, the CAA directs the EPA and the states to begin taking steps to ensure that those NAAQS are met. The first step is to identify areas of the country that do not meet the new or revised NAAQS. This step is known as the initial area designations. Section 107(d)(1)(A) of the CAA provides that, “By such date as the Administrator may reasonably require, but not later than 1 year after promulgation of a new or revised national ambient air quality standard for any pollutant under section [109], the Governor of each State shall * * * submit to the Administrator a list of all areas (or portions thereof) in the State” that designates those areas as nonattainment, attainment, or unclassifiable. The CAA defines an area as nonattainment if it is violating the NAAQS or if it is contributing to a violation in a nearby area. 42 U.S.C. 7407(d)(1)(A)(i).

The CAA further provides, “Upon promulgation or revision of a national ambient air quality standard, the Administrator shall promulgate the designations of all areas (or portions thereof) * * * as expeditiously as practicable, but in no case later than 2 years from the date of promulgation of the new or revised national ambient air quality standard. Such period may be extended for up to one year in the event the Administrator has insufficient information to promulgate the Start Printed Page 29247designations.” 42 U.S.C. 7407(d)(1)(B)(i).

After the states submit their recommendations, but no later than 120 days prior to promulgating designations, the EPA is required to notify a state of any intended modifications to the state's recommended designation. The state then has an opportunity to demonstrate why any proposed modification is inappropriate. Whether or not a state provides a recommendation, the EPA must promulgate the designation that the agency deems appropriate within 2 years of promulgation of the NAAQS (or within 3 years if the EPA extends the deadline).

For the 2015 ozone NAAQS, the deadline for states to submit designation recommendations to the EPA for their areas was October 1, 2016. The EPA has been evaluating these recommendations and conducting additional analyses to determine whether it is necessary to modify any of the state recommendations.

III. Extension of Deadline for Promulgating Designations for the 2015 NAAQS

In this action, the EPA is announcing that it is using its authority under section 107(d)(1)(B)(i) of the CAA to extend by 1 year the deadline for promulgating initial area designations for the 2015 ozone NAAQS. The new deadline is October 1, 2018. For the reasons explained in this notice, the EPA Administrator has determined that there is insufficient information to complete the designations by October 1, 2017.

Following the recent change in administrations, the agency is currently evaluating a host of complex issues regarding the 2015 ozone NAAQS and its implementation, such as understanding the role of background ozone levels and appropriately accounting for international transport. The Administrator has determined that he cannot assess whether he has the necessary information to finalize designations until additional analyses from this evaluation are available. In addition, pursuant to language in the recently-enacted Fiscal Year 2017 omnibus bill, the Administrator is establishing an Ozone Cooperative Compliance Task Force to develop additional flexibilities for states to comply with the ozone standard. It is possible the outcome of that effort could identify flexibilities that could impact the designations process. In light of the analyses currently underway at the agency, the Administrator has determined he needs additional time to consider completely all designation recommendations provided by state governors pursuant to CAA section 107(d)(1)(A), including full consideration of exceptional events impacting designations, and determine whether they provide sufficient information to finalize designations. We also note that new agency officials are currently reviewing the 2015 ozone NAAQS rule. The Administrator has determined that in light of the uncertainty of the outcome of that review, there is insufficient information to promulgate designations by October 1, 2017.

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List of Subjects in 40 CFR Part 81

  • Environmental protection
  • Air pollution control
  • National parks
  • Wilderness areas
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Dated: June 21, 2017.

E. Scott Pruitt,


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[FR Doc. 2017-13437 Filed 6-27-17; 8:45 am]