🌍Implications of New Air Quality Regulations for San Joaquin Valley
The Environmental Protection Agency (EPA) is proposing to approve the "2023 Maintenance Plan and Redesignation Request for the Revoked 1-Hour Ozone Standard" ("San Joaquin Valley Maintenance Plan" or "Plan") as a revision to the state implementation plan (SIP) for the State of California. The San Joaquin Valley Maintenance Plan includes, among other elements, an emissions inventory consistent with attainment and contingency provisions. The EPA is also proposing to find that the State of California's request to redesignate the San Joaquin Valley area from nonattainment to attainment for the revoked 1979 1-hour national ambient air quality standard (NAAQS or "standard") for ozone ("1979 ozone NAAQS," "1-hour ozone NAAQS," or "1-hour ozone standard") meets all the Clean Air Act (CAA or "the Act") criteria for redesignation. Therefore, the EPA is proposing to terminate all anti-backsliding obligations for the San Joaquin Valley area for the revoked 1-hour ozone NAAQS.
Learn More🌬️New EPA Delegation of NSPS and NESHAP to Louisiana
The Louisiana Department of Environmental Quality (LDEQ) has submitted updated regulations for receiving delegation and approval of its program for the implementation and enforcement of certain New Source Performance Standards (NSPS) and National Emission Standards for Hazardous Air Pollutants (NESHAP) for all sources, as provided for under previously approved delegation mechanisms. The updated State regulations incorporate by reference certain NSPS and NESHAP promulgated by the Environmental Protection Agency (EPA), as they existed through July 1, 2021. EPA is providing notice that it is updating the delegation of certain NSPS to LDEQ and proposing to approve the delegation of certain NESHAP to LDEQ. The proposed delegation of authority under this action does not apply to sources located in Indian country.
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🌫️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🌬️Proposed EPA Rule for Eastern Kern Air Quality
The Environmental Protection Agency (EPA) is proposing to approve a revision to the Eastern Kern Air Pollution Control District (EKAPCD or "District") portion of the California State Implementation Plan (SIP). This revision concerns emissions of oxides of nitrogen (NO<INF>X</INF>) from stationary gas turbines. We are proposing to approve a local rule to regulate these emission sources under the Clean Air Act (CAA or "Act"). We are taking comments on this proposal and plan to follow with a final action.
Learn More🌍EPA Delegates NESHAP Authority to Oklahoma for Air Quality Management
The Oklahoma Department of Environmental Quality (ODEQ) has submitted updated regulations for receiving delegation and approval of its program for the implementation and enforcement of certain National Emission Standards for Hazardous Air Pollutants (NESHAP) for all sources, as provided for under previously approved delegation mechanisms. The updated State regulations incorporate by reference certain NESHAP promulgated by the Environmental Protection Agency (EPA), as they existed through June 30, 2022. The EPA is providing notice that it is taking final action to approve the delegation of certain NESHAP to ODEQ. The final delegation of authority under this action applies to sources located in certain areas of Indian country as discussed herein.
Learn More🌫️EPA Proposes Air Quality Regulation Approvals for Colorado Businesses
The Environmental Protection Agency (EPA) is proposing to approve state implementation plan (SIP) submittals under the Clean Air Act (CAA) that address Reasonably Available Control Technology (RACT) requirements for the 2008 ozone National Ambient Air Quality Standards (NAAQS) for the Denver Metro/North Front Range (DMNFR) ozone nonattainment area. The requirements at issue relate to the area's previous Serious nonattainment classification. The EPA is proposing approval of the RACT SIP submittals, proposing to find that the State has met the applicable CAA requirements for Serious area RACT, and proposing that the State has addressed EPA's prior disapproval concerning specific RACT determinations. In this issue of the Federal Register the EPA is concurrently making an interim final determination to defer application of CAA sanctions associated with the prior disapproval. The EPA is taking this action pursuant to 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🌬️Corrections to Arizona Air Quality Implementation Plan by EPA
On January 16, 2025, the Environmental Protection Agency (EPA) published a final rule in the Federal Register approving revisions to the Maricopa County Air Quality Department (MCAQD or "County") portion of the Arizona State Implementation Plan (SIP). In that rulemaking, the EPA inadvertently published numbering errors in the regulatory text codifying the approval in the Code of Federal Regulations (CFR). This document corrects the errors in the final rule's regulatory text.
Learn More🌬️Proposed Updates to West Virginia's Air Quality Standards by EPA
The Environmental Protection Agency (EPA) is proposing to approve a state implementation plan (SIP) revision submitted by the State of West Virginia. This revision updates West Virginia's incorporation by reference (IBR) of EPA's national ambient air quality standards (NAAQS) and the associated monitoring reference and equivalent methods. This action is being taken under the Clean Air Act (CAA).
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