SUPPLEMENTARY INFORMATION:

Throughout this document “we,” “us,” and “our” refer to EPA.

Table of Contents

I. Written Comments

II. What is being addressed in this document?

III. Background Information

IV. What are the criteria for redesignating an area from unclassifiable to unclassifiable/attainment?

V. What is the EPA's rationale for proposing to redesignate the area?

VI. Proposed Action

VII. Statutory and Executive Order Reviews

I. Written Comments

Submit your comments, identified by Docket ID No. EPA-R07-OAR-2019-0190, at https://www.regulations.gov. Once submitted, comments cannot be edited or removed from Regulations.gov. The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission ( i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit https://www.epa.gov/​dockets/​commenting-epa-dockets.

II. What is being addressed in this document?

The EPA is proposing to approve MoDNR's request to change the designation of the Missouri portion of the St. Louis area from unclassifiable to unclassifiable/attainment for the 2012 PM_2.5 NAAQS, based on quality-assured and certified monitoring data for 2015-2017, and proposing to approve that the Missouri portion of the St. Louis area has met the requirements for redesignation under section 107(d)(3)(E) of the CAA.

III. Background Information

The Clean Air Act (CAA) establishes a process for air quality management through the establishment and implementation of the NAAQS. Upon promulgation of a new or revised NAAQS, section 107(d)(1)of the CAA requires EPA to designate areas as attainment, nonattainment, or unclassifiable. On December 14, 2012, the EPA promulgated a revised primary annual PM_2.5 NAAQS to provide increased protection of public health and welfare from fine particle pollution (78 FR 3086, January 15, 2013). In that action, the EPA revised the primary annual PM_2.5 standard, strengthening it from 15.0 micrograms per cubic meter (μg/m³ ) to 12.0 (μg/m³ ), which is attained when the three-year average of the annual arithmetic means does not exceed 12.0 (μg/m³ ). The EPA ( printed page 22102) established the standard based on significant evidence and numerous health studies demonstrating that serious health effects are associated with exposures to particulate matter.

The process for designating areas following promulgation of a new or revised NAAQS is contained in section 107(d)(1) of the CAA. On December 18, 2014, the EPA designated the majority of areas across the country as nonattainment, unclassifiable/attainment, or unclassifiable ^[1] for the 2012 PM_2.5 NAAQS based upon air quality monitoring data from monitors for calendar years 2011-2013. See80 FR 2206 (January 15, 2015).

The EPA initially designated the bi-state St. Louis area as unclassifiable based on ambient air quality data from 2011-2013. During that time period, the EPA identified data completeness issues with the ambient PM_2.5 monitoring data in the state of Illinois. Although all monitors in Missouri were attaining the standard at the time of the initial designations, the lack of complete monitoring data in Illinois prevented EPA from being able to determine whether violations of the standard were occurring in the Illinois portion of the St.Louis area or whether emission sources in Missouri were contributing to any violations in Illinois. Therefore, the EPA designated the entire St. Louis MO-IL area as unclassifiable for the 2012 PM_2.5 NAAQS.

IV. What are the criteria for redesignating an area from unclassifiable to unclassifiable/attainment?

Section 107(d)(3) of the CAA provides the framework for changing the area designations for any NAAQS pollutants. Section 107(d)(3)(A) provides that the Administrator may notify the Governor of any state that the designation of an area should be revised “on the basis of air quality data, planning and control considerations, or any other air quality-related considerations the Administrator deems appropriate.” The CAA further provides in section 107(d)(3)(D) that even if the Administrator has not notified a state Governor that a designation should be revised, the Governor of any state may, on the Governor's own motion, submit a request to revise the designation of any area, and the Administrator must approve or deny the request.

When approving or denying a request to redesignate an area, EPA bases its decision on the air quality data for the area as well as the considerations provided under section 107(d)(3)(A).^[2] In keeping with section 107(d)(1)(A), areas that are redesignated to unclassifiable/attainment must meet the requirements for attainment areas and thus must meet the relevant NAAQS. In addition, the area must not contribute to ambient air quality in a nearby area that does not meet the NAAQS. The relevant monitoring data must be collected and quality-assured in accordance with 40 CFR part 58 and recorded in the EPA Air Quality System (AQS) database. The designated monitors generally should have remained at the same location for the duration of the monitoring period upon which the redesignation request is based.^[3]

V. What is the EPA's rationale for proposing to redesignate the area?

To redesignate the area from unclassifiable to unclassifiable/attainment for the 2012 primary annual PM_2.5 NAAQS, the three-year average of the annual arimethic means does not exceed 12.0 (μg/m³ ) at all monitoring sites in the area over the full three-year period, as determined in accordance with 40 CFR 50.18 and appendix N of part 50. The EPA reviewed PM_2.5 monitoring data from the monitors in the St. Louis area for the 2012 PM_2.5 NAAQS for the three-year period from 2015-2017. As summarized in table 1, the design values for the monitors in the area for the 2015-2017 are below the 2012 PM_2.5 NAAQS. These data have been quality-assured, certified, and recorded in AQS by Missouri and Illinois, and the monitoring location has not changed during the monitoring period.

The EPA is proposing to redesignate the Missouri portion of the St. Louis area from unclassifiable to unclassifiable/attainment because the three-year design value meets the 2012 primary annual PM_2.5 NAAQS.

VI. Proposed Action

The EPA is proposing to approve the MoDNR's December 11, 2018, request to redesignate the Missouri's portion of the St. Louis area from unclassifiable to ( printed page 22103) unclassifiable/attainment for the 2012 primary annual PM_2.5 NAAQS. If finalized, approval of the redesignation request would change the legal designation, found at 40 CFR part 81, of the City of St. Louis and the counties of Franklin, Jefferson, St. Charles, and St. Louis from unclassifiable to unclassifiable/attainment for the 2012 primary annual PM_2.5 NAAQS.

VII. Statutory and Executive Order Reviews

Under the CAA, a redesignation of an area to unclassifiable/attainment is an action that affects the status of a geographical area and does not impose any additional regulatory requirements on sources beyond those imposed by state law. A redesignation to unclassifiable/attainment does not create any new requirements. Accordingly, this action merely proposes to redesignate an area to unclassifiable/attainment and does not impose additional requirements. For that reason, this proposed action:

• Is not a significant regulatory action subject to review by the Office of Management and Budget under Executive Orders 12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);
• Is not anExecutive Order 13771 (82 FR 9339, February 2, 2017) regulatory action because SIP approvals are exempted under Executive Order 12866.
• Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
• Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);
• Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);
• Does not have Federalism implications as specified inExecutive Order 13132 (64 FR 43255, August 10, 1999);
• Is not an economically significant regulatory action based on health or safety risks subject toExecutive Order 13045 (62 FR 19885, April 23, 1997);
• Is not a significant regulatory action subject toExecutive Order 13211 (66 FR 28355, May 22, 2001);
• Is not subject to requirements of the National Technology Transfer and Advancement Act (NTTA) because this rulemaking does not involve technical standards; and
• Does not provide EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, underExecutive Order 12898 (59 FR 7629, February 16, 1994).

This proposed action is not approved to apply on any Indian reservation land or in any other area where EPA or an Indian tribe has demonstrated that a tribe has jurisdiction. In those areas of Indian country, the proposed rule does not have tribal implications and will not impose substantial direct costs on tribal governments or preempt tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

For the reasons stated in the preamble, the EPA proposes to amend 40 CFR part 81 as set forth below:

1. The authority citation for part 81 continues to read as follows:

Authority: 42 U.S.C. 7401 et seq.

2. Section 81.326 is amended by revising the entry for “St. Louis Area, MO-IL” in the table entitled “Missouri—2012 Annual PM _2.5 NAAQS” to read as follows:

84 FR 22101