Regulations

On July 15, 2026, the U.S. Environmental Protection Agency (EPA) published a notice designating one new reference method for measuring carbon monoxide (CO), one new equivalent method for measuring particulate matter (PM) 2.5 micrometers ([micro]m) or less (PM<INF>2.5</INF>), one new equivalent method for measuring PM 10[micro]m or less (PM<INF>10</INF>), and one new equivalent method for measuring PM<INF>10-2.5</INF> in ambient air. After publication, the EPA realized that there was an error in the notice; therefore, this action corrects and replaces the July 15, 2026, designation notice.

The U.S. Environmental Protection Agency (EPA) is making available for public review the draft document titled, Integrated Science Assessment for Oxides of Nitrogen--Health Criteria, External Review Draft ("draft ISA"). This document was prepared as part of the current review of the primary (health-based) national ambient air quality standards (NAAQS) for oxides of nitrogen. The draft ISA will be available on or about July 15, 2026.

The U.S. Environmental Protection Agency (EPA) is making corrections to the New Source Performance Standards Review for Stationary Combustion Turbines and Stationary Gas Turbines final rule ("Final NSPS Rule") that published in the Federal Register (FR) on January 15, 2026, and became effective on January 15, 2026. After publication, the EPA identified inadvertent technical and typographical errors in the Federal Register regulatory text and is correcting those errors.

The Bodie Mine is a mine site located in Okanogan County, Washington. On June 11, 2026, Trout Unlimited Inc. (Trout Unlimited) applied for a Good Samaritan remediation permit pursuant to the Good Samaritan Remediation of Abandoned Hardrock Mines Act of 2024 (2024 Good Samaritan Act or Act). The EPA has preliminarily determined that the application is complete and meets all applicable requirements of the Act. The EPA has also made the preliminary determination that the site and parties are eligible for a Good Samaritan permit, the activities are low risk, and the activities will result in measurable progress towards achieving improved soil, sediment compared to baseline conditions at the site. After the comment period closes and all comments have been considered, the EPA will determine whether to grant the permit.

The Environmental Protection Agency (EPA) is taking direct final action to accept a negative declaration submitted by the Nebraska Department of Water, Energy, and Environment (NDWEE) to satisfy the emission guidelines and associated compliance times requirements for Commercial and Industrial Solid Waste Incineration (CISWI) units for the State of Nebraska. The negative declaration certifies that there are no existing sources within the jurisdiction of Nebraska that must comply with the rule. This action is being taken in accordance with the Clean Air Act (CAA) requirements for emission guidelines and state plans for existing sources.

The Environmental Protection Agency (EPA) is proposing to accept a negative declaration submitted by the Nebraska Department of Water, Energy, and Environment (NDWEE) to satisfy the emission guidelines and associated compliance times requirements for Commercial and Industrial Solid Waste Incineration (CISWI) units for the State of Nebraska. The negative declaration certifies that there are no existing sources within the jurisdiction of Nebraska that must comply with the rule. This action is being taken in accordance with the Clean Air Act (CAA) requirements for emission guidelines and state plans for existing sources. In the "Rules and Regulations" section of this Federal Register, we are approving the State's negative declaration submission as a direct final rule without a prior proposed rule. If we receive no adverse comment, we will not take further action on this proposed rule.

The Environmental Protection Agency (EPA) is making an interim final determination (IFD) that Pennsylvania has submitted revisions to the state implementation plan (SIP) that satisfy the requirements under the Clean Air Act (CAA) to implement Reasonably Available Control Technology (RACT) for volatile organic compounds (VOC) Control Technique Guidelines (CTG) for the 2008 ozone national ambient air quality standards (NAAQS). The effect of this IFD is to stay emission offset sanctions and defer the imposition of highway funding sanctions triggered by an August 16, 2024 EPA disapproval of a prior Pennsylvania SIP addressing VOC CTG RACT requirements for the 2008 ozone NAAQS. This IFD is consistent with a proposed action, published elsewhere in this issue of the Federal Register, in which the EPA is proposing approval of revisions to Pennsylvania's SIP, as submitted on May 10, 2023, January 20, 2026, February 17, 2026 and April 10, 2026 to address VOC CTG RACT requirements for the 2008 and 2015 NAAQS.

The Environmental Protection Agency (EPA) is proposing to approve four state implementation plan (SIP) revisions submitted by the Commonwealth of Pennsylvania received on May 10, 2023, January 20, 2026, February 17, 2026, and April 10, 2026, through the Pennsylvania Department of Environmental Protection (PADEP). The SIP revisions address reasonably available control technology (RACT) requirements for the 2008 and 2015 ozone national ambient air quality standards (NAAQS) relating to control technique guidelines (CTGs) for volatile organic compounds (VOC) via previously adopted CTG regulations, three new CTG regulations and four facilities covered by the CTG for the Manufacture of High-Density Polyethylene, Polypropylene, and Polystyrene Resins respectively. This action is being taken under the Clean Air Act (CAA).

The Environmental Protection Agency (EPA) is taking final action to approve revisions to the Iowa State Implementation Plan (SIP) and the Operating Permit Program to incorporate recent changes to the Iowa Administrative Code (IAC). The revisions include removal of the Voluntary Operating Permit (VOP) Program language; removal of the Emission Reduction Program language; new and renumbered rules; replacement of duplicative language with references to state statute and federal regulations; updated definitions; consolidation of 14 chapters into 8 chapters; and minor clarifications to language and grammar. The EPA is also finalizing corrections to the erroneous incorporation of several rules into the Iowa SIP pursuant to the Clean Air Act (CAA). These revisions do not decrease the stringency of the SIP or have an adverse effect on air quality. The EPA's final approval of this rule revision is in accordance with the requirements of the CAA.

The U.S. Environmental Protection Agency (EPA or Agency) is approving the attainment plan and comprehensive emissions inventory for the Canton Nonattainment Area for the 2008 Lead (Pb) National Ambient Air Quality Standards (NAAQS) submitted by the Ohio Environmental Protection Agency (Ohio EPA or Ohio) on September 19, 2024. Additionally, the EPA is determining that the Canton Nonattainment Area has attained the 2008 Pb NAAQS and is approving Ohio's April 25, 2025, maintenance plan for continued attainment. With these approvals, the EPA is acting in accordance with Ohio's request to redesignate the Canton Nonattainment Area from nonattainment to attainment of the 2008 Pb NAAQS. The EPA is taking these actions in accordance with the Clean Air Act (CAA) and the Agency's implementation regulations regarding the 2008 Pb NAAQS. The EPA proposed these actions on March 27, 2026, with publication in the Federal Register on April 10, 2026, and we received no adverse comments.

The Environmental Protection Agency (EPA) is finalizing an approval of seven permitting rules as a revision to the Antelope Valley Air Quality Management District (AVAQMD or "District") portion of the California State Implementation Plan (SIP). These revisions concern the District's New Source Review (NSR) permitting program for new and modified sources of air pollution under part D of title I of the Clean Air Act (CAA or "Act"). The revised rules address deficiencies identified in a previous limited disapproval action, correct a newly identified deficiency for one permitting rule, and incorporate other revisions related to NSR requirements. This action updates the District's portion of the California SIP with the revised rules.

The Environmental Protection Agency (EPA) Administrator signed an order dated June 9, 2026, denying a petition dated September 9, 2024, from RISE St. James, Healthy Gulf, Louisiana Bucket Brigade, Sierra Club, and Earthjustice (Petitioners). The petition requested that the EPA object to a Clean Air Act (CAA) title V operating permit issued by the Louisiana Department of Environmental Quality (LDEQ) to Mitsubishi Chemical America, Inc. for its MCA Geismar Site located in Geismar, Ascension Parish, Louisiana.

In accordance with the Clean Air Act, as amended (CAA or the Act), notice is given of a proposed consent decree in Center for Biological Diversity et al. v. Lee Zeldin, No. 3:25-cv-6568-AMO. On August 5, 2025, Plaintiffs Center for Biological Diversity and Sierra Club filed a complaint in the United States District Court, Northern District of California, San Francisco Division. The EPA designated various areas of the country as nonattainment with respect to the 2010 SO<INF>2</INF> NAAQS. States that contain areas that are designated as nonattainment are required to provide State Implementation Plan submissions to the EPA within 18 months of the effective date of designations. The EPA is providing notice of this proposed consent decree, which would resolve all claims in the case by establishing deadlines for the EPA to take final action as specified in the decree.

The Environmental Protection Agency (EPA) is proposing to approve a revision to the State of Wisconsin's State Implementation Plan (SIP) for the Oak Creek Power Plant located in Oak Creek, Wisconsin. The EPA is proposing to approve alternative nitrogen oxides (NO<INF>X</INF>) emissions limits for the Oak Creek facility. The alternative limits will allow the facility to operate in compliance with State and Federal regulations, and emit less NO<INF>X</INF> over time as compared to current limits. This proposed action will not interfere with the National Ambient Air Quality Standards (NAAQS) and meets all applicable requirements under the Clean Air Act (CAA).

Pursuant to applicable requirements under the Clean Air Act (CAA or the Act), the Environmental Protection Agency (EPA) is proposing to approve a revision to the State of New York's State Implementation Plan (SIP) for the ozone National Ambient Air Quality Standard (NAAQS) related to a source-specific SIP (SSSIP) revision for Castleton Energy Center, located at 1902 River Road, Castle-on-Hudson, New York 12033 (herein referred to CEC, or the Facility). The EPA is proposing to find that the control option in this SSSIP revision is Reasonably Available Control Technology (RACT) with respect to oxides of nitrogen (NO<INF>X</INF>) emissions from the relevant Facility emission source, i.e., a combined-cycle combustion turbine generator with an associated heat recovery steam generator equipped with a duct burner, and a steam generator, identified as emission unit 1-0GTDB in the Facility's CAA Title V operating permit. This SSSIP revision is intended to implement NO<INF>X</INF> RACT for the relevant Facility source in accordance with the requirements for implementation of the 2008 and 2015 ozone NAAQS. The EPA proposes to determine that this action will not interfere with ozone NAAQS requirements and meets all applicable requirements of the Act.

The Environmental Protection Agency (EPA) is proposing to approve revisions to the Missouri State Implementation Plan (SIP) related to Control of Nitrogen Oxide (NO<INF>X</INF>) Emissions From Large Stationary Internal Combustion Engines. The revisions reformat and revise reporting, recordkeeping, and compliance requirements; incorporate other state rules by reference; add definitions specific to the rule; revise unnecessarily restrictive or duplicative language; and make administrative wording changes. The revisions also add an exemption for certain spark-ignited internal combustion engines. The EPA's proposed approval is pursuant to, and consistent with, the requirements of the Clean Air Act (CAA).

Notice is hereby given that the U.S. Environmental Protection Agency (EPA) has designated one new reference method for measuring carbon monoxide (CO), one new equivalent method for measuring particulate matter (PM) 2.5 micrometers ([micro]m) or less (PM<INF>2.5</INF>), one new equivalent method for measuring PM 10[micro]m or less (PM<INF>10</INF>), and one new equivalent method for measuring PM<INF>10-2.5</INF> in ambient air.

The Environmental Protection Agency (EPA or the Agency) is proposing to approve the Alabama partial Coal Combustion Residuals (CCR) permit program under the Resource Conservation and Recovery Act (RCRA). After reviewing the CCR permit program application submitted by the Alabama Department of Environmental Management (ADEM) on May 18, 2026, EPA has preliminarily determined that Alabama's partial CCR permit program meets the standard for approval under RCRA. If approved, Alabama's CCR permit program will operate in lieu of the Federal CCR program, with the exception of the specific provisions noted below. EPA is seeking comment on this proposal during a 60-day public comment period and will be holding a virtual public hearing on EPA's preliminary approval of Alabama's partial CCR permit program.

The Environmental Protection Agency (EPA) issued a proposed rule on February 20, 2020, to establish a Federal permit program for disposal of coal combustion residuals (CCR). On April 13, 2026, the EPA proposed to establish new compliance pathways that would allow site- specific considerations to be taken into account during permitting for owners or operators of CCR units complying with groundwater monitoring, corrective action, and closure requirements under a federal or participating-State CCR permit. The EPA is considering whether a general permit could be developed to allow such facilities to temporarily obtain permit coverage until an individual permit issued by EPA or an approved state CCR permit program is in effect. This advance notice of proposed rulemaking (ANPRM) does not propose any regulatory requirements or change any existing regulatory requirements.