Air Plan Approval; Rhode Island; Regional Haze State Implementation Plan for the Second Implementation Period; Prong 4 (Visibility) for the 2015 8-Hour Ozone National Ambient Air Quality Standard

ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R01-OAR-2025-0915 and EPA-R01-OAR-2020-0562; FRL-13065-01-R1]</DEPDOC> <SUBJECT>Air Plan Approval; Rhode Island; Regional Haze State Implementation Plan for the Second Implementation Period; Prong 4 (Visibility) for the 2015 8-Hour Ozone National Ambient Air Quality Standard</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Environmental Protection Agency (EPA). <HD SOURCE="HED">ACTION:</HD> Proposed rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The Environmental Protection Agency (EPA) is proposing to approve the regional haze state implementation plan (SIP) revision submitted by Rhode Island on March 7, 2025, as satisfying applicable requirements under the Clean Air Act (CAA) and EPA's Regional Haze Rule (RHR) for the program's second implementation period. Rhode Island's SIP submission addresses the requirement that states must periodically revise their long-term strategies for making reasonable progress towards the national goal of preventing any future, and remedying any existing, anthropogenic impairment of visibility, including regional haze, in mandatory Class I Federal areas. The SIP submission also addresses other applicable requirements for the second implementation period of the regional haze program. EPA is also proposing to approve the remaining element of Rhode Island's September 23, 2020, infrastructure SIP submittal for the 2015 ozone National Ambient Air Quality Standards (NAAQS). The proposed approval of Rhode Island's second implementation period regional haze plan addresses infrastructure SIP requirements related to visibility protection. The EPA is taking this action pursuant to sections 110 and 169A of the Clean Air Act. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> Written comments must be received on or before December 22, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Submit your comments, identified by Docket ID No. EPA-R01-OAR-2025-0915 at <E T="03">https://www.regulations.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 <E T="03">Regulations.gov.</E> For either manner of submission, 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 ( <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 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> Ayla Martinelli, Air Quality Branch, U.S. Environmental Protection Agency, EPA Region 1, 5 Post Office Square—Suite 100, (Mail code 5-MI), Boston, MA 02109—3912, tel. (617) 918-1057, email <E T="03">martinelli.ayla@epa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Table of Contents</HD> <EXTRACT> <FP SOURCE="FP-2">I. What action is the EPA proposing?</FP> <FP SOURCE="FP-2">II. Background and Requirements for Regional Haze Plans</FP> <FP SOURCE="FP1-2">A. Regional Haze Background</FP> <FP SOURCE="FP1-2">B. Roles of Agencies in Addressing Regional Haze</FP> <FP SOURCE="FP-2">III. Requirements for Regional Haze Plans for the Second Implementation Period</FP> <FP SOURCE="FP1-2">A. Long-Term Strategy for Regional Haze</FP> <FP SOURCE="FP1-2">B. Reasonable Progress Goals</FP> <FP SOURCE="FP1-2">C. Monitoring Strategy and Other State Implementation Plan Requirements</FP> <FP SOURCE="FP1-2">D. Requirements for Periodic Reports Describing Progress Towards the Reasonable Progress Goals</FP> <FP SOURCE="FP1-2">E. Requirements for State and Federal Land Manager Coordination</FP> <FP SOURCE="FP-2">IV. The EPA's Evaluation of Rhode Island's Regional Haze Submission for the Second Implementation Period</FP> <FP SOURCE="FP1-2">A. Background on Rhode Island's First Implementation Period SIP Submission</FP> <FP SOURCE="FP1-2">B. Rhode Island's Second Implementation Period SIP Submission and the EPA's Evaluation</FP> <FP SOURCE="FP1-2"> C. Identification of Class I Areas </FP> <FP SOURCE="FP1-2">D. Calculations of Baseline, Current, and Natural Visibility Conditions; Progress to Date; and the Uniform Rate of Progress</FP> <FP SOURCE="FP1-2">E. Long-Term Strategy for Regional Haze</FP> <FP SOURCE="FP1-2">a. Rhode Island's Response to the Six MANEVU Asks</FP> <FP SOURCE="FP1-2">b. The EPA's Evaluation of Rhode Island's Response to the Six MANEVU Asks and Compliance With 40 CFR51.308(f)(2)(i)</FP> <FP SOURCE="FP1-2">c. Additional Long-Term Strategy Requirements</FP> <FP SOURCE="FP1-2">F. Reasonable Progress Goals</FP> <FP SOURCE="FP1-2">G. Monitoring Strategy and Other Implementation Plan Requirements</FP> <FP SOURCE="FP1-2">H. Requirements for Periodic Reports Describing Progress Towards the Reasonable Progress Goals</FP> <FP SOURCE="FP1-2">I. Requirements for State and Federal Land Manager Coordination</FP> <FP SOURCE="FP1-2">J. Other Required Commitments</FP> <FP SOURCE="FP-2">V. EPA's Evaluation of Rhode Island's Infrastructure SIP</FP> <FP SOURCE="FP1-2">A. Background and Purpose</FP> <FP SOURCE="FP1-2">B. Section 110(a)(2)(D)(i)(II)—Visibility Protection</FP> <FP SOURCE="FP-2">VI. Proposed Action</FP> <FP SOURCE="FP-2">VII. Statutory and Executive Order Reviews </FP> </EXTRACT> <HD SOURCE="HD1">I. What action is the EPA proposing?</HD> On March 7, 2025, the Rhode Island Department of Environmental Management (RIDEM) submitted a revision to its SIP to address regional haze for the second implementation period. RIDEM made this SIP submission to satisfy the requirements of the CAA's regional haze program pursuant to CAA sections 169A and 169B and 40 CFR 51.308. The EPA is proposing to find that the Rhode Island regional haze SIP submission for the second implementation period meets the applicable statutory and regulatory requirements and thus proposes to approve Rhode Island's submission into its SIP. On September 23, 2020, RIDEM submitted a SIP revision addressing, among other CAA requirements, the CAA section 110(a)(2)(D)(i)(II) visibility protection requirements for the 2015 ozone NAAQS. EPA is proposing to find that, with the approval of the state's regional haze plan, the SIP will contain adequate provisions to satisfy the requirements of CAA section 110(a)(2)(D)(i)(II) relating to visibility protection. <HD SOURCE="HD1">II. Background and Requirements for Regional Haze Plans</HD> A detailed history and background of the regional haze program is provided in multiple prior EPA proposal actions. <SU>1</SU> <FTREF/> For additional background on the 2017 RHR revisions, please refer to Section III. Overview of Visibility Protection Statutory Authority, Regulation, and Implementation of “Protection of Visibility: Amendments to Requirements for State Plans” of the 2017 RHR. <SU>2</SU> <FTREF/> The following is an abbreviated history and background of the regional haze program and 2017 Regional Haze Rule as it applies to the current action. <FTNT> <SU>1</SU>  For example, see 90 FR 13516 (March 24, 2025). </FTNT> <FTNT> <SU>2</SU>  See 82 FR 3078 (January 10, 2017). </FTNT> <HD SOURCE="HD2">A. Regional Haze Background</HD> In the 1977 CAA Amendments, Congress created a program for protecting visibility in the nation's mandatory Class I Federal areas, which include certain national parks and wilderness areas. <SU>3</SU> <FTREF/> CAA 169A. The CAA establishes as a national goal the “prevention of any future, and the remedying of any existing, impairment of visibility in mandatory class I Federal areas which impairment results from manmade air pollution.” CAA 169A(a)(1). <FTNT> <SU>3</SU>  Areas statutorily designated as mandatory Class I Federal areas consist of national parks exceeding 6,000 acres, wilderness areas and national memorial parks exceeding 5,000 acres, and all international parks that were in existence on August 7, 1977. CAA 162(a). There are 156 mandatory Class I areas. The list of areas to which the requirements of the visibility protection program apply is in 40 CFR part 81, subpart D. </FTNT> Regional haze is visibility impairment that is produced by a multitude of anthropogenic sources and activities that are located across a broad geographic area and that emit pollutants that impair visibility. Visibility impairing pollutants include fine and coarse particulate matter (PM) ( <E T="03">e.g.,</E> sulfates, nitrates, organic carbon, elemental carbon, and soil dust) and their precursors ( <E T="03">e.g.,</E> sulfur dioxide (SO <E T="52">2</E> ), nitrogen oxides (NO <E T="52">X</E> ), and, in some cases, volatile organic compounds (VOC) and ammonia (NH <E T="52">3</E> )). Fine particle precursors react in the atmosphere to form fine particulate matter (PM <E T="52">2.5</E> ), which impairs visibility by scattering and absorbing light. Visibility impairment reduces the perception of clarity and color, as well as visible distance. <SU>4</SU> <FTREF/> <FTNT> <SU>4</SU>  There are several ways to measure the amount of visibility impairment, <E T="03">i.e.,</E> haze. One such measurement is t ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 147k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━