🌍Proposed Clean Data Determination for Guam's Piti-Cabras Area
The Environmental Protection Agency (EPA) is proposing a clean data determination (CDD) for the Piti-Cabras, Guam sulfur dioxide (SO<INF>2</INF>) nonattainment area ("Piti-Cabras area") based on our determination that the area has attained the 2010 1-hour SO<INF>2</INF> National Ambient Air Quality Standard (NAAQS, "standard," or "2010 SO<INF>2</INF> NAAQS"). In designated nonattainment areas where air quality data demonstrate that a NAAQS has been attained, the EPA interprets certain requirements of the Clean Air Act (CAA) as no longer applicable for so long as air quality continues to meet the standard. Under this Clean Data Policy, the EPA may issue a determination of attainment, known as a CDD, that a nonattainment area is attaining the relevant NAAQS. If finalized, this proposed CDD would suspend the obligation to submit certain attainment planning requirements for the Piti-Cabras area for as long as the area continues to attain the 2010 SO<INF>2</INF> NAAQS or until the area is formally redesignated.
Learn More🌫️Missouri's St. Louis Area Reclassified as Serious Ozone Nonattainment
The Environmental Protection Agency (EPA) is accepting comment on a determination that the Missouri portion of the St. Louis, MO-IL bi-state nonattainment area failed to attain the 2015 8-hour ozone National Ambient Air Quality Standards (NAAQS) by the applicable attainment date. The effect of failing to attain by the applicable attainment date is that the area is reclassified by operation of law to "Serious" nonattainment for the 2015 ozone NAAQS. On November 25, 2024, the EPA published a final action in the Federal Register which determined that the St. Louis area failed to attain the 2015 ozone NAAQS by the Moderate area attainment date. That action also reclassified the area to Serious by operation of law with an effective date of December 31, 2024. On January 24, 2025, the EPA received a petition for reconsideration of that final action from the State of Missouri. On March 5, 2025, EPA Region 7 granted the petition for reconsideration and stated our intention to undergo a notice and comment rulemaking. Therefore, the EPA is accepting comment on the determination that the St. Louis area failed to attain by the attainment date. The Illinois portion of the St. Louis, MO-IL bi-state area is addressed separately.
Learn More🌱EPA Defers Sanctions for California Air Quality Compliance
The Environmental Protection Agency (EPA) is making an interim final determination that the California Air Resources Board (CARB) has submitted a rule on behalf of the Eastern Kern Air Pollution Control District (EKAPCD or "District") that addresses deficiencies in its Clean Air Act (CAA or "Act") State Implementation Plan (SIP) concerning emissions of oxides of nitrogen (NO<INF>X</INF>) from stationary gas turbines. This determination is based on a proposed approval, published elsewhere in this issue of the Federal Register, of EKAPCD Rule 425 that regulates this category of sources. The effect of this interim final determination is that the application of offset sanctions that was triggered by a previous limited disapproval by the EPA in 2023 is now stayed, and the application of highway sanctions is now deferred. If the EPA finalizes its approval of EKAPCD's submission, relief from these sanctions will become permanent.
Learn More🌱Proposed RFS Changes for 2026 and 2027
Under the Clean Air Act (CAA), the Environmental Protection Agency (EPA) is required to determine the applicable volume requirements for the Renewable Fuel Standard (RFS) for years after those specified in the statute. EPA is proposing the applicable volumes and percentage standards for 2026 and 2027 for cellulosic biofuel, biomass-based diesel (BBD), advanced biofuel, and total renewable fuel. EPA is also proposing to partially waive the 2025 cellulosic biofuel volume requirement and revise the associated percentage standard due to a shortfall in cellulosic biofuel production. Finally, EPA is proposing several regulatory changes to the RFS program, including reducing the number of Renewable Identification Numbers (RINs) generated for imported renewable fuel and renewable fuel produced from foreign feedstocks and removing renewable electricity as a qualifying renewable fuel under the RFS program (eRINs).
Learn More💰Proposed Repeal of Emission Standards for Coal and Oil Utilities
In this action, the U.S. Environmental Protection Agency (EPA) is proposing to repeal specific amendments to the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Coal- and Oil-Fired Electric Utility Steam Generating Units (EGUs), commonly referred to as the Mercury and Air Toxics Standards (MATS), that were promulgated on May 7, 2024. The amendments that the EPA is proposing to repeal include the revised filterable particulate matter (fPM) emission standard, which serves as a surrogate for non-mercury hazardous air pollutant (HAP) metals for existing coal-fired EGUs; the revised fPM emission standard compliance demonstration requirements; and the revised mercury (Hg) emission standard for lignite-fired EGUs.
Learn More🌫️California Regional Haze Plan Approval
The Environmental Protection Agency (EPA) is proposing to approve the regional haze state implementation plan (SIP) revision submitted by California on August 9, 2022 (hereinafter the "2022 California Regional Haze Plan" or "the Plan"), under the Clean Air Act (CAA) and the EPA's Regional Haze Rule for the program's second implementation period. California'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. The EPA is proposing this action pursuant to CAA sections 110 and 169A. The EPA is also withdrawing its previous proposed rule to partially approve and partially disapprove California's regional haze SIP revision as published in the Federal Register on December 19, 2024.
Learn More🌫️Indiana's Regional Haze Plan
The Environmental Protection Agency (EPA) is proposing to approve the Indiana regional haze state implementation plan (SIP) revision submitted by the Indiana Department of Environmental Management (IDEM or Indiana) on December 29, 2021, as satisfying applicable requirements under the Clean Air Act (CAA) and EPA's Regional Haze Rule (RHR) for the program's second implementation period. EPA proposes to find that IDEM'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, and also addresses other applicable requirements for the second implementation period of the regional haze program. EPA is taking this action pursuant to sections 110 and 169A of the CAA.
Learn More🌫️EPA Defers Sanctions in Colorado Ozone Nonattainment Area
In the Proposed Rules section of this Federal Register, EPA is proposing approval of portions of State Implementation Plan (SIP) submissions from the State of Colorado dated June 26, 2023, May 23, 2024, May 30, 2024, and April 2, 2025. The submissions relate to Colorado Air Quality Control Commission Regulation Number 7 (Reg. 7) and Regulation Number 26 (Reg. 26), and address Colorado's SIP obligations for the Reasonably Available Control Technology (RACT) Serious ozone nonattainment area requirement for the 2008 ozone National Ambient Air Quality Standard (NAAQS). In this action, the EPA is making an interim final determination based on that proposed approval. The effect of this interim final determination is that the imposition of sanctions that were triggered by the EPA's December 8, 2023 disapproval are now deferred. Although this action is effective on publication, the EPA will take comment on this interim final determination.
Learn More🌫️EPA Proposes Finding of Failure to Attain SO2 Standards in Indiana
The Environmental Protection Agency (EPA) is proposing to find that the Huntington County, Indiana nonattainment area failed to attain the 2010 Sulfur Dioxide (SO<INF>2</INF>) National Ambient Air Quality Standard (NAAQS) by the applicable attainment date of April 9, 2023. EPA is also proposing to approve revisions into the Indiana State Implementation Plan (SIP) intended to provide for attainment of the 2010 SO<INF>2</INF> NAAQS for the Huntington County nonattainment area. These SIP submissions include Indiana's attainment demonstration and other planning elements required under the Clean Air Act (CAA), and a Commissioner's Order containing enforceable emission limits. Further, EPA is proposing to find that the provisions of Indiana's SIP submittal adequately provide for attainment of the NAAQS and that the plan meets all other applicable CAA requirements.
Learn More🌫️Proposed EPA Regulations Impacting Utah Air Quality Standards
Pursuant to the Federal Clean Air Act (CAA or the Act), the Environmental Protection Agency (EPA) is proposing to approve a portion of a Utah State Implementation Plan (SIP) submission addressing interstate transport for the 2008 8-hour ozone national ambient air quality standard (NAAQS). The "interstate transport" provision requires that each state's SIP contain adequate provisions to prohibit emissions from within the state from significantly contributing to nonattainment or interfering with maintenance of the NAAQS in other states. In this action, EPA is only addressing the requirement prohibiting interference with maintenance, referred to as "prong 2," for the 2008 ozone NAAQS.
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