Air Plan Approval; Illinois; NAAQS Update

<RULE> ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R05-OAR-2024-0105; EPA-R05-OAR-2024-0320; FRL-12240-02-R5]</DEPDOC> <SUBJECT>Air Plan Approval; Illinois; NAAQS Update</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Environmental Protection Agency (EPA). <HD SOURCE="HED">ACTION:</HD> Direct final rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The Environmental Protection Agency (EPA) is approving State Implementation Plan (SIP) revisions submitted by the Illinois Environmental Protection Agency (IEPA or Illinois). The revisions, submitted on February 26, 2024, and July 8, 2024, incorporate amendments to the Illinois air pollution control rules entitled “Part 243—Ambient Air Quality Standards” in response to EPA rulemakings and changes to the National Ambient Air Quality Standards (NAAQS) that EPA adopted in 2022 and 2023. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This direct final rule will be effective December 2, 2024, unless EPA receives adverse comments by November 4, 2024. If adverse comments are received, EPA will publish a timely withdrawal of the direct final rule in the <E T="04">Federal Register</E> informing the public that the rule will not take effect. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Submit your comments, identified by Docket ID No. EPA-R05-OAR-2024-0105 at <E T="03">https://www.regulations.gov,</E> or via email to <E T="03">arra.sarah@epa.gov.</E> For comments submitted at <E T="03">Regulations.gov</E> , follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from the docket. EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI), Proprietary Business Information (PBI), 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. EPA will generally not consider comments or comment contents located outside of the primary submission ( <E T="03">i.e.</E> on the web, cloud, or other file sharing system). For additional submission methods, please contact the person identified in the <E T="02">FOR FURTHER INFORMATION CONTACT</E> section. For the full EPA public comment policy, information about CBI, PBI, or multimedia submissions, and general guidance on making effective comments, please visit <E T="03">https://www.epa.gov/dockets/commenting-epa-dockets.</E> <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Mayesha Choudhury, Air and Radiation Division (AR-18J), Environmental Protection Agency, Region 5, 77 West Jackson Boulevard, Chicago, Illinois 60604, (312) 886-5909, <E T="03">choudhury.mayesha@epa.gov.</E> The EPA Region 5 office is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding Federal holidays. </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> Throughout this document whenever “we,” “us,” or “our” is used, we mean EPA. <HD SOURCE="HD1">I. Background</HD> <HD SOURCE="HD2">A. Illinois Submittals</HD> On February 26 and July 8, 2024, IEPA submitted revisions to the SIP that update Part 243 in Title 35 of the Illinois Administrative Code (IAC). The SIP submissions update section 243.108 of Title 35 by incorporating EPA's updated “List of Designated Reference and Equivalent Methods,” which is used to determine compliance with the NAAQS (fine particulate matter and coarse particulate matter, sulfur dioxide (SO <E T="52">2</E> ), carbon monoxide, lead, oxides of nitrogen, and ozone). The February 2024 submission includes EPA's designation of one new equivalent method for measuring concentrations of fine particulate matter (PM <E T="52">2.5</E> ) in ambient air. <SU>1</SU> <FTREF/> This designation was enacted and effective on October 5, 2023. The July 2024 submission incorporates EPA's designation of a new equivalent method for measuring Particulate Matter (PM <E T="52">10</E> ) in ambient air, also found in section 243.108. <SU>2</SU> <FTREF/> The designation was enacted and effective May 16, 2024. <FTNT> <SU>1</SU>   <E T="03">See</E> 87 FR 65203 (October 28, 2022). </FTNT> <FTNT> <SU>2</SU>   <E T="03">See</E> 88 FR 76212 (November 6, 2023). </FTNT> The July 2024 submission also incorporates references to EPA's updated ozone absorption cross-section value, <SU>3</SU> <FTREF/> which is a standard parameter used to measure concentrations of ozone, and makes corrections to section 243.125(b)(3) to reflect word style used by EPA in past NAAQS amendments. <FTNT> <SU>3</SU>   <E T="03">See</E> 88 FR 70595 (October 12, 2023). </FTNT> <HD SOURCE="HD2">B. List of Designated and Reference Equivalent Methods</HD> EPA evaluates various methods for monitoring the concentrations of criteria pollutants under the NAAQS. Equivalent methods for measuring criteria pollutants are designated by EPA as monitoring methods that meet specific requirements for determining compliance with the NAAQS under 40 CFR part 58. On October 28, 2022, EPA designated one new equivalent method for measuring concentrations of PM <E T="52">2.5</E> in ambient air. <SU>4</SU> <FTREF/> The new method, EQPM-0922-260 “Ambilabs Model 2WIN PM <E T="52">2.5</E> FEM Monitor,” is an automated method (analyzer) utilizing an optically based measurement principle. <FTNT> <SU>4</SU>   <E T="03">See supra</E> note 1. </FTNT> On November 6, 2023, EPA designated a new equivalent method for measuring concentrations of PM <E T="52">10</E> in ambient air. <SU>5</SU> <FTREF/> The new method, EQPM-0923-262 “Vashti Instruments Pvt. Ltd Vair-9009 p.m. <E T="52">10</E> Monitor,” is an automated monitoring method (monitor) utilizing the measurement principle based on beta-ray attenuation. <FTNT> <SU>5</SU>   <E T="03">See supra</E> note 2. </FTNT> <HD SOURCE="HD2">C. Update to Ozone Absorption Cross-Section Value</HD> On October 5, 2023, EPA updated the ozone absorption cross-section value, which is used in ultraviolet-based ozone analyzers and Standard Reference Photometers. The new value represents an increased accuracy of surface ozone monitoring measurements and reduced uncertainty in ozone measured concentrations. <SU>6</SU> <FTREF/> EPA updated references in the regulations regarding this value  <SU>7</SU> <FTREF/> and Illinois's July 2024 submittal amends the existing corresponding state rules to provide consistency with the Federal regulations. <FTNT> <SU>6</SU>   <E T="03">See supra</E> note 3. </FTNT> <FTNT> <SU>7</SU>   <E T="03">See</E> 40 CFR part 50, appendix D—Reference Measurement Principle and Calibration Procedure for the Measurement of Ozone in the Atmosphere (Chemiluminescence Method). </FTNT> <HD SOURCE="HD1">II. What is EPA's analysis of the State's submittals?</HD> <E T="03">Section 243.108—Incorporation by Reference</E> incorporates EPA's updates to its “List of Designated Reference and Equivalent Methods” for measuring ambient concentrations to demonstrate compliance with the NAAQS. The SIP revision would update section 243.108 to incorporate the changes from EPA's actions dated October 28, 2022 (87 FR 65203) and November 6, 2023 (88 FR 76212). <E T="03">Section 243.125—Ozone</E> incorporates EPA's references to the updated ozone absorption cross-section value. The SIP revision would update word style in section 243.125 and would make a minor correction to a reference to an EPA regulation regarding the measurement of ozone (40 CFR part 50, appendix D). EPA has reviewed the state revisions and finds that they are equivalent to EPA requirements and strengthen the Illinois SIP. <HD SOURCE="HD1">III. What action is EPA taking?</HD> EPA is approving the revisions to 35 IAC 243.108 as outlined in Illinois' February 26, 2024, and July 8, 2024, submittals. We are publishing this action without prior proposal because we view these as noncontroversial amendments and anticipate no adverse comments. However, in the proposed rules section of this <E T="04">Federal Register</E> publication, we are publishing a separate document that will serve as the proposal to approve the state plan if relevant adverse written comments are filed. This rule will be effective December 2, 2024 without further notice unless we receive relevant adverse written comments by November 4, 2024. If we receive such comments, we will withdraw this action before the effective date by publishing a subsequent document that will withdraw the final action. All public comments received will then be addressed in a subsequent final rule based on the proposed action. EPA will not institute a second comment period. Any parties interested in commenting on this action should do so at this time. Please note that if EPA receives adverse comment on an amendment, paragraph, or section of this rule and if that provision may be severed from the remainder of the rule, EPA may adopt as final those provisions of the rule that are not the subject of an adverse comment. If we do not receive any comments, this action will be effective December 2, 2024. <HD SOURCE="HD1">IV. Incorporation by Reference</HD> In this rule, EPA is finalizing regulatory text that includes incorporation by reference. In accordance with requirements of 1 CFR 51.5, EPA is finalizing the incorporation by reference of the Illinois regulations described in section I of this preamble and set forth in the amendments to 40 CFR part 52 below. EPA has made, and will continue to make, these documents generally available through <E T="03">www.regulations.gov</E> and at the EPA Region 5 Office (please contact the person identified in the <E T="0 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 17k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━