Emissions standards

Current understanding

EPA rules setting pollution or greenhouse-gas limits for vehicles, power plants, or industry.

Evidence log

• 2025-01-13 — Preserving Choice in Vehicle Purchases Act: 2025 — Preserving Choice in Vehicle Purchases Act (introduced House bill) would bar EPA from granting CAA §209 waivers for state rules limiting sales or use of new gasoline and diesel vehicles, and would revoke any such waivers issued since Jan 1, 2022, directly targeting California’s ACC II/ACT ZEV sales mandates and §177 adoption by other states. (novelty: 3)
• 2026-08-27 — Air Plan Approval; Oklahoma; Regional Haze Plan for the First Implementation Revision; Revision to State Implementation Plan and Requirements: 2025 — EPA proposed to approve Oklahoma’s SIP revision under the regional haze first implementation period, updating source-specific air-pollution requirements for the AEP/PSO Northeastern Power Station; routine source-specific regional haze SIP action rather than new pollutant limits. (novelty: 2)
• 2026-08-31 — Resetting NHTSA’s Fuel Economy Program: Commercial Medium- and Heavy-Duty On-Highway Vehicles and Work Trucks: cross-connection with nhtsa-mdhd-fuel-economy: NHTSA’s narrowing of heavy-duty fuel-economy authority runs parallel to EPA’s separate GHG/criteria pollutant standards for heavy-duty engines and vehicles; divergence between the two programs affects manufacturer compliance planning. (novelty: 3)
• 2026-08-19 — Air Plan Partial Approval and Partial Conditional Approval; South Carolina; Control of Oxides of Nitrogen and Source Testing Requirements: 2025 — EPA proposed partial approval and partial conditional approval of South Carolina SIP revisions updating NOx control requirements and source testing procedures for stationary sources, with conditional portions contingent on further state fixes; routine state-specific SIP action rather than new national pollutant limits. (novelty: 2)
• 2026-08-13 — Air Plan Approval; Commonwealth of Virginia; Transfer of Authority and Requests for Certain Public Hearings on Air Permits: 2025 — EPA proposed to approve a Virginia SIP revision transferring air-permit, order, and variance authority from the State Air Pollution Control Board to the Department of Environmental Quality and codifying public-hearing procedures for controversial air permits; tangential to emissions-standards page (state permitting-authority reassignment and procedural change rather than pollutant emission limits). (novelty: 2)
• 2026-08-14 — Air Plan Approval; Iowa; Interstate Transport Requirements for the 2010 Sulfur Dioxide Standard: 2025 — EPA proposed to approve Iowa’s interstate transport SIP submission for the 2010 SO2 NAAQS, finding the state’s existing SO2 emission levels do not significantly contribute to nonattainment or interfere with maintenance in downwind states under CAA §110(a)(2)(D)(i)(I) (good neighbor provision); routine state-specific transport SIP action rather than new pollutant limits. (novelty: 2)
• 2026-08-14 — Air Plan Approval; Missouri; Moderate Attainment Plan Elements for the 2015 8-Hour Ozone Standard for the Missouri Portion of the St. Louis Nonattainment Area: 2026 — EPA proposed to approve Missouri SIP submissions covering vehicle I/M, nonattainment NSR, and source-specific VOC/NOx RACT determinations as meeting CAA §182 Moderate ozone requirements for the Missouri portion of the St. Louis area; incremental RACT/permitting SIP action rather than new pollutant limits. (novelty: 2)
• 2025-01-09 — Restoring Energy Market Freedom Act: 2026 — Restoring Energy Market Freedom Act (introduced) would repeal federal tax credits for renewables, nuclear, carbon sequestration, hydrogen, advanced coal/gasification, and advanced energy/semiconductor manufacturing; tangential to emissions-standards page (tax incentive repeal that could indirectly shift emissions trajectories rather than pollutant limits). (novelty: 3)
• 2026-08-06 — Air Plan Approval; Illinois; 2015 Ozone Moderate and Serious Reasonably Available Control Technology Update: 2025 — EPA proposed to approve Illinois SIP revisions (35 IAC 217, 218, 219) as meeting Moderate VOC and NOx RACT and Serious NOx RACT for the Chicago and Metro-East St. Louis 2015 ozone nonattainment areas; incremental RACT SIP action rather than new pollutant limits. (novelty: 2) (novelty: 2)
• 2026-07-02 — Rinnai America Corporation v. South Coast Air Quality Management District: 2026-07-02 — Rinnai America Corporation v. South Coast Air Quality Management District: Ninth Circuit issued an opinion in Rinnai America Corp. v. South Coast AQMD, a challenge by a water-heater manufacturer to a local air district’s low-/zero-NOx appliance rules; caption and date only in abstract, so holding and any effect on state/local authority to set appliance-related NOx emission limits is undetermined. (novelty: 2)
• 2023-02-17 — Water Quality and Environmental Innovation Act: 2025 — Water Quality and Environmental Innovation Act (HR873) would redirect Motor Vehicle and Engine Compliance Program fee collections via annual transfer to a new EPA water-quality innovation fund through FY2028; tangential to emissions-standards page (repurposes vehicle compliance fees for water-quality R&D grants rather than changing pollutant limits). (novelty: 3)
• 2026-07-21 — No Passes for Polluters Act of 2026: 2026 — No Passes for Polluters Act of 2026 (HR9808) introduced and referred to House Energy and Commerce and Rules Committees; would restrict regulatory exemptions or waivers granted to polluters; tangential to emissions-standards page (House companion/analog to prior S4404, addressing exemption framework rather than new pollutant limits). (novelty: 2)
• 2026-04-27 — No Passes for Polluters Act of 2026: 2026 — No Passes for Polluters Act of 2026 (S4404) introduced and referred to Senate Environment and Public Works, proposing to limit exemptions or waivers granted to polluters; tangential to emissions-standards page (enforcement/exemption framework rather than new pollutant emission limits). (novelty: 2)
• 2026-07-30 — Clean Air Act Operating Permit Program Revisions; California; Amador County Air Pollution Control District, Calaveras County Air Pollution Control District, Great Basin Unified Air Pollution Control District, Northern Sierra Air Quality Management District: 2025 — EPA proposed approval of Title V operating permit program revisions by four California air districts (Amador, Calaveras, Great Basin Unified, Northern Sierra) removing emergency affirmative defense provisions to align local rules with federal Clean Air Act requirements; tangential to emissions-standards page (Title V permit-program defense mechanism rather than pollutant emission limits). (novelty: 2) (novelty: 2)
• 2026-07-30 — Air Plan Approval; Pennsylvania; Redesignation of the Warren County Nonattainment Area to Attainment and Approval of the Area’s Maintenance Plan for the 2010 1-Hour Primary Sulfur Dioxide National Ambient Air Quality Standard: 2025 — EPA proposed Warren County, PA redesignation to attainment for the 2010 1-hour SO2 NAAQS with maintenance plan approval and corrections to source-specific SIP requirements for United Refining Company; tangential to emissions-standards page (area redesignation and SIP correction rather than new pollutant limits). (novelty: 2) (novelty: 2)
• 2025-03-27 — Providing for congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Environmental Protection Agency relating to “Review of Final Rule Reclassification of Major Sources as Area Sources Under Section 112 of the Clean Air Act”.: CRA joint resolution introduced to nullify EPA’s September 2024 final rule that required former major sources of persistent and bioaccumulative HAPs to keep meeting major-source NESHAP standards after reclassifying as area sources under CAA §112; companion effort to S.J. Res. 31, would restore the pre-rule reversal of ‘once in, always in’ and ease compliance for reclassified sources. (novelty: 2)
• 2026-07-23 — Providing congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Environmental Protection Agency relating to “California State Motor Vehicle Pollution Control Standards; Notice of Decision Granting a Waiver of Clean Air Act Preemption for California’s Advanced Clean Car Program and a Within the Scope Confirmation for California’s Zero Emission Vehicle Amendments for 2017 and Earlier Model Years”.: 2025 — H.J.Res. 205 introduced as a CRA joint resolution to disapprove EPA’s waiver of Clean Air Act preemption for California’s Advanced Clean Car Program and its Zero-Emission Vehicle amendments for 2017-and-earlier model years; if enacted, would nullify that waiver and block §177 adoption of those ZEV/ACC requirements by other states. (novelty: 2)
• 2026-07-18 — Providing congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Environmental Protection Agency relating to “California State Motor Vehicle Pollution Control Standards; Notice of Decision Granting a Waiver of Clean Air Act Preemption for California’s 2009 and Subsequent Model Year Greenhouse Gas Emission Standards for New Motor Vehicles”.: 2025 — CRA joint resolution introduced to disapprove EPA’s waiver of Clean Air Act preemption for California’s 2009-and-later model year greenhouse gas emission standards for new motor vehicles; if enacted, would nullify the GHG light-duty waiver and block §177 adoption by other states. (novelty: 2)
• 2025-06-12 — Providing congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Environmental Protection Agency relating to “California State Motor Vehicle and Engine Pollution Control Standards; Heavy-Duty Vehicle and Engine Emission Warranty and Maintenance Provisions; Advanced Clean Trucks; Zero Emission Airport Shuttle; Zero-Emission Power Train Certification; Waiver of Preemption; Notice of Decision”.: 2025 — Congress enacted CRA joint resolution (Public Law 119-15) nullifying EPA’s waiver of Clean Air Act preemption for California’s heavy-duty emission warranty, Advanced Clean Trucks, zero-emission airport shuttle, and zero-emission powertrain certification programs, blocking enforcement of those California heavy-duty ZEV standards and their §177 adoption by other states. (novelty: 3)
• 2026-07-14 — Diesel Emissions Reduction Act of 2025: 2025 — Diesel Emissions Reduction Act of 2025 introduced to reauthorize through FY2029 the EPA DERA grant/rebate/loan program funding replacement or pollution-control retrofits of diesel engines; tangential to emissions-standards page (funding program reauthorization rather than pollutant emission limits). (novelty: 2)
• 2026-07-17 — Clean Air Council v. EPA: 2026-07-17 — D.C. Circuit issued an opinion in Clean Air Council v. EPA; caption only, holding and statutory basis not stated in abstract, so effect on EPA emissions rules is undetermined. (novelty: 2)
• 2026-07-16 — Air Plan Approval; Pennsylvania; Interim Final Determination To Stay and Defer Sanctions Related to Reasonably Available Control Technology Requirements (RACT) for Volatile Organic Compounds (VOC) Control Technique Guidelines (CTG) Under the 2008 Ozone National Ambient Air Quality Standards (NAAQS): 2025 — EPA interim final determination that Pennsylvania’s SIP revisions satisfy VOC CTG RACT requirements for the 2008 ozone NAAQS, staying emission offset sanctions and deferring highway funding sanctions; tangential to emissions-standards page (SIP RACT sanction stay/defer rather than new pollutant limit). (novelty: 2)
• 2026-07-16 — Regulatory Relief for Certain Stationary Sources To Promote American Chemical Manufacturing Security: 2025 — Presidential document from the Executive Office of the President grants targeted regulatory relief to certain stationary sources to promote American chemical manufacturing security, easing Clean Air Act compliance obligations for covered facilities on national-security grounds; tangential to emissions-standards page (source-specific relief tied to industrial policy rather than a new pollutant limit). (novelty: 3)
• 2026-04-27 — FIRE Act: 2025 — FIRE Act (HR6387) introduced to broaden Clean Air Act exceptional-events coverage (human-set fires mirroring natural events, certain meteorological conditions) and direct EPA to revise treatment of wildfire-mitigation activities in NAAQS exceedance data; tangential to emissions-standards page (exceedance data treatment rather than pollutant emission limits). (novelty: 3)
• 2026-07-14 — Amendments and Nonconformance Penalties for Model Year 2027 and Later Heavy-Duty Highway Engines and Amendments to Inducement Provisions for SCR-Equipped Diesel Engines: 2025 — EPA proposed amendments for MY 2027+ heavy-duty highway engines revising compliance/test procedures, useful life and warranty periods, nonconformance penalty (NCP) availability, and SCR inducement requirements for diesel engines; adjusts implementation of the existing HD engine emissions standards rather than establishing new pollutant limits. (novelty: 2)
• 2026-07-15 — Air Plan Approval; Wisconsin; Source-Specific Air Quality Implementation Plan; Oak Creek Power Plant: 2025 — EPA proposed to approve a source-specific SIP revision for Wisconsin’s Oak Creek Power Plant establishing alternative NOx emission limits that reduce NOx over time while not interfering with NAAQS attainment or maintenance under CAA §110(l). (novelty: 2)
• 2025-03-14 — Providing for congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Environmental Protection Agency relating to “Waste Emissions Charge for Petroleum and Natural Gas Systems: Procedures for Facilitating Compliance, Including Netting and Exemptions”.: 2025 — Congress passed CRA joint resolution (H.J. Res. 35) nullifying EPA’s rule establishing procedures (including netting and exemptions) for the Waste Emissions Charge on petroleum and natural gas systems, effectively eliminating the annual methane waste charge under the Methane Emissions Reduction Program and removing a compliance-cost pathway on upstream/midstream oil-and-gas methane emissions. (novelty: 3)
• 2025-06-20 — A joint resolution providing for congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Environmental Protection Agency relating to “Review of Final Rule Reclassification of Major Sources as Area Sources Under Section 112 of the Clean Air Act”.: 2025 — Congress passed CRA joint resolution (S.J. Res. 31) nullifying EPA’s 2024 rule that required former major sources of persistent/bioaccumulative HAPs to continue meeting major-source NESHAP standards after reclassifying as area sources under CAA §112; nullification restores the pre-rule ‘once in, always in’ reversal and eases compliance burdens for reclassified sources. (novelty: 3)
• 2026-06-26 — Commonwealth of Kentucky v. EPA: 2026-06-26 — D.C. Circuit issued an opinion in Commonwealth of Kentucky v. EPA; caption only, holding and statutory basis not stated in abstract, so effect on EPA emissions rules is undetermined. (novelty: 2)
• 2026-04-17 — FENCES Act: 2025 — FENCES Act (introduced) would carve out Clean Air Act sanctions and nonattainment consequences for states when emissions causing NAAQS shortfalls originate from foreign sources or exceptional events; tangential to emissions-standards page (nonattainment consequence relief rather than pollutant emission limits). (novelty: 3)
• 2025-02-14 — Ocean Pollution Reduction Act II: 2025 — Ocean Pollution Reduction Act II (HR1390) introduced, would authorize a site-specific conditional NPDES permit with tailored treatment standards for the Point Loma Wastewater Treatment Plant in lieu of recurring Clean Water Act §301(h) variance applications; tangential to emissions-standards page (Clean Water Act wastewater permitting rather than air-pollutant emission limits). (novelty: 2) (novelty: 2)
• 2025-10-14 — Diesel Truck Liberation Act of 2025: 2025 — Diesel Truck Liberation Act of 2025 (S3007) introduced in the 119th Congress and referred to the Senate Committee on Environment and Public Works, proposing to roll back or restrict federal emissions requirements on diesel trucks; tangential to emissions-standards page (legislative proposal affecting heavy-duty vehicle emission rules). (novelty: 2)
• 2025-02-13 — Nationwide Consumer and Fuel Retailer Choice Act of 2025: 2025 — Nationwide Consumer and Fuel Retailer Choice Act of 2025 introduced to extend the Clean Air Act 1-psi RVP waiver from E10 to E15 for year-round nationwide sales, preempt state E15 exclusions, and modify small refinery RFS compliance credits; tangential to emissions-standards page (fuel volatility/RFS blend rules rather than direct pollutant emission limits). (novelty: 2)
• 2026-04-16 — Stop Climate Shakedowns Act of 2026: 2026 — Stop Climate Shakedowns Act of 2026 (S4340) introduced and referred to Senate Judiciary, seeking to restrict state-level climate liability lawsuits against energy companies; tangential to emissions-standards page (litigation preemption rather than pollutant emission limits). (novelty: 2) (novelty: 2)
• 2026-06-25 — Data Infrastructure Energy Measurement and Standards Act: 2026-06 — Data Infrastructure Energy Measurement and Standards Act (HR9372) ordered reported by House committee 34-1, advancing federal measurement/standards framework for data center energy use; tangential to emissions-standards page (energy-use measurement regime rather than pollutant emission limits). (novelty: 2)
• 2025-05-20 — Providing for consideration of the joint resolution (S.J. Res. 13) providing for congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Office of the Comptroller of the Currency of the Department of the Treasury relating to the review of applications under the Bank Merger Act; providing for consideration of the joint resolution (S.J. Res. 31) providing for congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Environmental Protection Agency relating to “Review of Final Rule Reclassification of Major Sources as Area Sources Under Section 112 of the Clean Air Act”; and waiving a requirement of clause 6(a) of rule XIII with respect to consideration of certain resolutions reported from the Committee on Rules.: 2025 — House rule (procedural) waiving points of order for floor consideration of a CRA joint resolution (S.J. Res. 31) to disapprove EPA’s rule reclassifying major sources as area sources under Clean Air Act Section 112; if enacted, would nullify the reclassification rule affecting NESHAP applicability thresholds. (novelty: 2)
• 2026-07-09 — Air Plan Approval; Michigan; Redesignation and Maintenance Plan for the Partial St. Clair 2010 1-Hour Sulfur Dioxide (SO2) NAAQS Nonattainment Area: 2025 — EPA final rule redesignating the partial St. Clair, Michigan area to attainment for the 2010 1-hour SO2 NAAQS and approving Michigan’s maintenance plan, which includes SO2 emission limits for the DTE Belle River Power Plant; illustrates area-specific SIP-based emission limits on a coal EGU as a maintenance mechanism. (novelty: 2)
• 2026-07-09 — Approval and Promulgation of Implementation Plans; California; San Joaquin Valley; Revisions to Motor Vehicle Emissions Budgets for Ozone: 2025 — EPA proposed approval of updated San Joaquin Valley motor vehicle emissions budgets (NOx and VOC) for 2026/2029/2031 under the 2008 ozone NAAQS; tangential to emissions-standards page (transportation conformity budgets tied to a SIP rather than pollutant emission limits). (novelty: 2)
• 2025-11-18 — Climate Solutions Act of 2025: 2025 — Climate Solutions Act of 2025 (introduced) would direct EPA to set annual GHG reduction targets on a trajectory to 52% reduction by 2035 and net-zero by 2050, and impose a 100% renewable electricity mandate by 2035; represents proposed statutory GHG limits layered on top of existing EPA emissions-standards authority. (novelty: 3)
• 2025-11-18 — A bill to require the Secretary of Housing and Urban Development and the Secretary of Agriculture to withdraw a final determination relating to energy efficiency standards for housing, and for other purposes.: 2025 — S3178 introduced to require HUD and USDA to withdraw the 2024 energy efficiency standards determination for federally financed new construction and to bar future code updates unless at least 26 states have already adopted equivalent standards; tangential to emissions-standards page (building energy code adoption for federally financed housing rather than pollutant emission limits). (novelty: 2)
• 2025-12-12 — Zero Food Waste Act: 2025 — Zero Food Waste Act (HR6684) introduced, would direct EPA to establish a grant program for states, local, territorial, tribal governments, and nonprofits to study and reduce food waste; tangential to emissions-standards page (waste-reduction grant program rather than pollutant emission limits). (novelty: 2) (novelty: 2)
• 2023-03-21 — Energy Freedom Act: 2025 — Energy Freedom Act (S879, introduced) would expedite permitting for natural gas and pipeline projects and mandate minimum federal energy lease sales; tangential to emissions-standards page (permitting timelines and leasing floors rather than pollutant emission limits). (novelty: 2)
• 2024-12-17 — Preventing HEAT Illness and Deaths Act of 2024: 2024 — Preventing HEAT Illness and Deaths Act of 2024 (S2645) would create federal extreme-heat health coordination (OSTP interagency committee, NOAA heat health information system, community grants); tangential to emissions-standards page (heat-health response infrastructure rather than pollutant emission limits). (novelty: 3)
• 2025-11-18 — Fracturing Responsibility and Awareness of Chemicals Act of 2025: 2025 — FRAC Act of 2025 (introduced) would extend EPA SDWA authority to hydraulic fracturing and mandate chemical disclosure; tangential to emissions-standards page (groundwater and chemical disclosure rather than air/water pollutant emission limits). (novelty: 3)
• 2025-01-21 — Community Protection and Wildfire Resilience Act: 2025 — HR582 (Community Protection and Wildfire Resilience Act) introduced to establish a new USFA wildfire resilience grant program, expand USFS Community Wildfire Defense Grants to cover home hardening/construction, and require new wildfire risk mapping and reporting; tangential to emissions-standards page (wildfire resilience grant program rather than pollutant emission limits). (novelty: 2)
• 2026-03-24 — A bill to amend the Internal Revenue Code of 1986 to extend the clean electricity production credit and the clean electricity investment credit based on increases in the price of, and demand for, electricity, and for other purposes.: 2025 — S4175 introduced to amend the Internal Revenue Code to extend the clean electricity production credit (§45Y) and clean electricity investment credit (§48E) with eligibility triggers based on increases in electricity prices and demand; tangential to emissions-standards page (tax-credit phase-out mechanics rather than pollutant emission limits). (novelty: 2)
• 2026-05-07 — Defense Federal Acquisition Regulation Supplement: Disclosure of Greenhouse Gas Emissions (DFARS Case 2024-D021): 2025 — DoD proposed DFARS amendment (Case 2024-D021) to require defense contractors to disclose greenhouse gas emissions, implementing an FY2024 NDAA provision; tangential to emissions-standards page (procurement disclosure regime rather than pollutant emission limits). (novelty: 2)
• 2025-03-14 — IMPACT Act 2.0: 2025 — IMPACT Act 2.0 (HR2122) introduced, would direct FHWA to reimburse states for the incremental cost of low-emissions cement, concrete, and asphalt in highway projects and authorize advance purchase commitments for greener/superior-performance materials under the Surface Transportation Block Grant program; tangential to emissions-standards page (federal-aid procurement incentive for low-embodied-carbon materials rather than pollutant emission limits). (novelty: 2)
• 2026-06-24 — End EPA Abuse Act of 2026: 2026 — End EPA Abuse Act of 2026 (S4931) introduced in the 119th Congress and referred to the Senate Committee on Environment and Public Works, proposing to curtail EPA regulatory authority; tangential to emissions-standards page (broad agency-authority restriction rather than specific pollutant emission limits). (novelty: 2)
• 2026-07-07 — Minor New Source Review Program Air Permitting Public Participation Requirements for State Implementation Plans: 2025 — EPA proposed to give state and local air agencies greater discretion over the level of public participation required in minor New Source Review permitting programs under State Implementation Plans; tangential to emissions-standards page (permit-program procedural discretion rather than pollutant emission limits). (novelty: 2)
• 2026-07-07 — Energy Conservation Program: Review of DOE’s Analytic Methods for Setting Energy Conservation Standards: 2025 — DOE soliciting public comment on the assumptions, models, and methodologies used to set energy conservation standards for covered products/equipment, including feedback on a National Academies review of those methods; tangential to emissions-standards page (appliance/equipment efficiency analytical methodology rather than pollutant emission limits). (novelty: 2)
• 2026-07-07 — Energy Conservation Program: Procedures, Interpretations, and Policies for Consideration of New or Revised Energy Conservation Standards and Test Procedures for Consumer Products and Certain Commercial/Industrial Equipment: 2025 — DOE proposed to update its Energy Conservation Program rulemaking Process Rule, reinstating 2020 procedural requirements, adding economic significance thresholds, and aligning with recent executive orders; tangential to emissions-standards page (appliance/equipment efficiency rulemaking methodology rather than pollutant emission limits). (novelty: 2)
• 2026-07-07 — Endangered and Threatened Wildlife and Plants; Threatened Species Status With Section 4(d) Rule for the Kern Canyon Slender Salamander and Endangered Species Status for the Relictual Slender Salamander; Designation of Critical Habitat: 2025 — FWS reopened the public comment period on proposed ESA listings, 4(d) rule, and critical habitat for the Kern Canyon and relictual slender salamanders; tangential to emissions-standards page (ESA species protection rather than pollutant emission limits). (novelty: 2)
• 2026-05-08 — Air Plan Approval; NC; Removal of the State’s Vehicle Inspection and Maintenance Program: 2025 — EPA proposed to approve North Carolina’s SIP revision removing its vehicle inspection and maintenance (I/M) program, finding removal will not interfere with Clean Air Act attainment or reasonable further progress requirements under CAA §110(l). (novelty: 2)
• 2026-05-13 — Begin Actual Construction in the New Source Review (NSR) Preconstruction Permitting Program: 2025 — EPA proposed to revise NSR preconstruction permitting regulations by updating the definition of ‘begin actual construction’ and adding a definition of ‘pollutant-emitting activities,’ allowing construction of non-emitting components or structures before an air permit is issued; tangential to emissions-standards page (permit-timing scope rather than pollutant limits). (novelty: 2)
• 2026-05-14 — Air Plan Approval; Illinois; Moderate Attainment Plan Elements for the Chicago and Metro East Areas for the 2015 Ozone Standard: 2025 — EPA approval of Illinois Moderate area SIP elements (RFP, MVEBs, I/M, NNSR, 2017 base year inventories) for the Chicago and Metro East St. Louis 2015 ozone NAAQS nonattainment areas illustrates the standard Section 182 Moderate area compliance package. (novelty: 2)
• 2026-05-18 — Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category-Unmanaged Combustion Residual Leachate: 2025 — EPA proposed revisions to the Steam Electric Power Generating ELGs addressing unmanaged combustion residual leachate, projected to reduce industry compliance costs by $446M–$1,090M annually; tangential to emissions-standards page (Clean Water Act effluent limits on power-plant wastewater rather than air-pollutant emission standards). (novelty: 2)
• 2026-05-18 — Revision of Tier 4 Criteria Pollutant Standards, Part 1: Amendments to Phase-In Schedule for Light-Duty and Medium-Duty Vehicles: 2025 — EPA proposed rule (Part 1) to delay Tier 4 criteria pollutant emissions standards phase-in for light-duty and medium-duty vehicles, extending Tier 3 standards through MY 2027–2028 and pushing Tier 4 compliance to MY 2029, citing changing circumstances and feasibility concerns. (novelty: 3)
• 2025-03-26 — ESG Act of 2025: 2025 — ESG Act of 2025 introduced, requiring brokers/dealers/investment advisers to base best-interest determinations on pecuniary factors unless the customer directs otherwise; tangential to emissions-standards page (investment-advice fiduciary standard affecting ESG/climate factor use rather than pollutant emission limits). (novelty: 3)
• 2026-06-24 — Artificial Intelligence Data Center Moratorium Act: 2025 — HR9442 (Artificial Intelligence Data Center Moratorium Act) introduced and referred to House Energy and Commerce and Foreign Affairs, proposing a moratorium on AI data centers; tangential to emissions-standards page (infrastructure siting/energy-demand intervention rather than pollutant emission limits). (novelty: 3)
• 2025-02-11 — Financing Our Energy Future Act: 2025 — S510 (Financing Our Energy Future Act) introduced to expand publicly traded partnership qualifying income under IRC §7704 to renewables, advanced nuclear, energy storage, hydrogen, and carbon capture; tangential to emissions-standards page (tax pass-through eligibility rather than pollutant limits). (novelty: 3)
• 2026-03-27 — To amend the Internal Revenue Code of 1986 to establish tax credits for the production of, and investment in, certain renewable materials.: 2025 — HR8137 introduced to amend the Internal Revenue Code to establish production and investment tax credits for certain renewable materials; tangential to emissions-standards page (tax-code incentive rather than pollutant emission limits). (novelty: 3, status: introduced) (novelty: 3)
• 2026-05-26 — Phasedown of Hydrofluorocarbons: Excluding Road and Intermodal Container Transport Refrigeration Units From the Hydrofluorocarbon Leak Repair Requirements: 2025 — EPA proposed to exempt road and intermodal container transport refrigeration units (TRUs) from HFC leak repair requirements under the AIM Act’s 2024 final rule, framing the change as a clarification that mobile TRUs were never intended to be covered; tangential to emissions-standards page (HFC equipment servicing rather than pollutant emission limits). (novelty: 2)
• 2026-05-29 — Significant New Use Rules on Certain Chemical Substances (25-2.5e): 2025 — EPA issued Significant New Use Rules under TSCA Section 5 requiring 90-day advance notification before manufacture or processing of certain chemical substances subject to prior PMNs and Section 5(e) orders; tangential to emissions-standards page (chemical premarket oversight rather than pollutant emission limits). (novelty: 2)
• 2026-05-29 — Partial Approval and Partial Disapproval of Air Quality Implementation Plans; Hawaii; Regional Haze State Implementation Plan for the Second Implementation Period: 2025 — EPA partially approved and partially disapproved Hawaii’s Regional Haze SIP for the second implementation period, rejecting the long-term strategy that relied on planned shutdowns of electric generating units on Hawaii and Maui islands. (novelty: 2)
• 2026-05-29 — Air Plan Approval; California; San Joaquin Valley Unified Air Pollution Control District; Ventura County Air Pollution Control District; South Coast Air Quality Management District; Oil and Gas Production; Volatile Organic Compounds: 2025 — EPA final rule approving California SIP revisions for three air districts (San Joaquin Valley, Ventura County, South Coast) regulating VOC emissions from crude oil and natural gas production facilities under the Clean Air Act. (novelty: 2)
• 2026-06-01 — Rescission of Title V Emergency Affirmative Defense Rule: 2025 — EPA rescinding its 2023 rule that had removed emergency affirmative defense provisions from Title V operating permit programs, reinstating those provisions to comply with a D.C. Circuit decision; tangential to emissions-standards page (permit-program defense mechanism rather than pollutant limits). (novelty: 2)
• 2026-06-03 — National Emission Standards for Hazardous Air Pollutants From Hazardous Waste Combustors: Residual Risk and Technology Review: 2025 — EPA finalized the Residual Risk and Technology Review for the Hazardous Waste Combustor NESHAP, concluding existing standards adequately protect public health while adding new emission limits for hydrogen fluoride and hydrogen cyanide at major-source incinerators, cement kilns, and boilers. (novelty: 2)
• 2026-06-03 — Rescission of Climate-Related Disclosure Rules: 2025 — SEC proposed rescission of its 2024 climate-related disclosure rules would eliminate mandatory registrant reporting of climate risks and Scope 1/2 GHG emissions in SEC filings; tangential to emissions-standards page (disclosure regime rather than pollutant limits). (novelty: 3, status: proposed-rule) (novelty: 3)
• 2026-06-04 — Conditional Approval; Contingency Measure State Implementation Plan for the 2008 Ozone Standards; San Joaquin Valley, California: 2025 — EPA conditional approval of San Joaquin Valley’s 2008 ozone NAAQS contingency measure SIP illustrates the Section 172©(9)/182 contingency measure obligation, with full approval contingent on California submitting additional measures within one year. (novelty: 2) (novelty: 2)
• 2026-06-08 — Air Plan Approval; Minnesota; Revision to Taconite Federal Implementation Plan: 2025 — EPA finalized NOx BART emission limits for U.S. Steel’s Keetac taconite indurating furnace in Minnesota under a revised Federal Implementation Plan, setting 3.4 lbs NOx/MMBtu for natural gas firing and 2.0 lbs NOx/MMBtu for other fuels on a rolling 720-hour average. (novelty: 2)
• 2026-06-08 — Approval and Promulgation of Air Quality Implementation Plans; Wyoming; Regional Haze Federal Implementation Plan: 2025 — EPA proposed to revise Wyoming’s regional haze Federal Implementation Plan by withdrawing and updating the NOx BART requirements for PacifiCorp’s Dave Johnston Power Plant Unit 3 after the operator withdrew consent to closure, replacing the closure-based BART determination in the 2014 FIP with updated emission limits. (novelty: 2)
• 2026-06-11 — Attainment Date Extension for the South Coast, California 2012 Annual PM2.5 Fine Particulate Matter Nonattainment Area: 2025 — EPA proposed to extend the ‘Serious’ PM2.5 attainment deadline for the Los Angeles-South Coast 2012 annual PM2.5 nonattainment area from Dec 31, 2025 to Dec 31, 2030, finding California met the statutory extension criteria; tangential to core emissions-standards page (specific nonattainment area deadline action). (novelty: 2)
• 2026-06-12 — Ozone Reclassification State Implementation Plan Rule: 2025 — EPA proposed rule on ozone reclassification SIP obligations would narrow Section 182 requirements applied after a nonattainment area “bump-up” to those tied to its new classification only, affecting RACT, offset, and contingency measure obligations for states. (novelty: 3)
• 2026-06-12 — Partial Withdrawals of Findings of Failure To Submit State Implementation Plan (SIP) Revisions To Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown, and Malfunction: 2025 — EPA partially withdrew findings of failure to submit SIP revisions for 13 states regarding excess emissions during startup, shutdown, and malfunction (SSM) periods, conforming to the D.C. Circuit’s partial vacatur of the underlying 2015 SIP call. (novelty: 2, status: final-rule) (novelty: 2)
• 2026-06-15 — Energy Conservation Program: Energy Conservation Standards for Distribution Transformers: 2025 — DOE request for information on the 2024 Energy Conservation Standards for Distribution Transformers, examining conflicts with a Presidential national-security determination and burdens on domestic manufacturers ahead of the 2029 compliance deadline; tangential to emissions rules (grid equipment efficiency rather than pollutant emissions). (novelty: 2)
• 2026-06-22 — Congressional Review Act Revocation of 2024 Amendments to the National Emission Standards for Hazardous Air Pollutants: Rubber Tire Manufacturing: 2025 — EPA removing from the CFR the 2024 NESHAP amendments for Rubber Tire Manufacturing following Congressional Review Act joint resolution of disapproval; effect is to nullify the 2024 tightening of hazardous air pollutant standards for tire manufacturing facilities. (novelty: 2)
• 2026-06-22 — EPCRA Hazardous Chemical Inventory Reporting Requirements: Conformity With the 2024 OSHA Hazard Communication Standard: 2025 — EPA final rule updating EPCRA hazardous chemical inventory reporting requirements to conform terminology and hazard categories with OSHA’s 2012 and 2024 Hazard Communication Standard amendments; tangential to emissions rules (chemical hazard reporting rather than air/water emissions limits). (novelty: 2)
• 2026-06-26 — Air Plan Approval; District of Columbia; Creation of Synthetic Minor Permit Program: 2025 — EPA final rule approving a District of Columbia SIP revision to establish a federally enforceable synthetic minor permit program, allowing sources of criteria pollutants to accept enforceable limits to stay below major-source thresholds under the Clean Air Act. (novelty: 2, status: final-rule) (novelty: 2)
• 2026-06-26 — Air Plan Approval; Ohio; Source-Specific Non-CTG RACT: 2025 — EPA finalized Ohio’s source-specific non-CTG RACT SIP revisions imposing VOC/NOx limits on three Cleveland-area facilities to complete Moderate area RACT obligations under the 2015 ozone NAAQS. (novelty: 2)
• 2026-06-26 — Air Plan Approval; Ohio; Source-Specific Non-CTG RACT and SIP Strengthening for Ohio: 2025 — EPA final rule approving Ohio source-specific non-CTG RACT SIP revisions setting VOC and NOx limits on facilities in the Cleveland nonattainment and Cincinnati maintenance areas under the 2015 ozone NAAQS. (novelty: 2)
• 2026-06-26 — U.S. Ecology Nevada, Inc. High Mercury Subcategory Wastes Land Disposal Restrictions Variance: 2025 — EPA final rule granting U.S. Ecology Nevada a conditional site-specific treatability variance permitting elemental mercury from retorting high mercury wastes to be treated and land disposed at RCRA-compliant facilities rather than returned to commerce; tangential to emissions rules (mercury waste management pathway). (novelty: 2)
• 2026-06-29 — Air Plan Approval; Ohio; Redesignation of the Cleveland, OH Area to Attainment of the 2015 Ozone Standard: 2025 — EPA final rule approving Ohio’s redesignation of the Cleveland area to attainment for the 2015 ozone NAAQS, along with the state’s maintenance plan, motor vehicle emissions budgets, and vehicle inspection program revisions. (novelty: 2, status: final-rule) (novelty: 2)
• 2025-03-06 — Renewable Fuel for Ocean-Going Vessels Act: 2025 — HR1896 (Renewable Fuel for Ocean-Going Vessels Act) introduced and referred to House Energy and Commerce, proposing to extend renewable fuel standards/incentives to marine vessels. (novelty: 2, status: introduced) (novelty: 2)
• 2025-02-25 — Providing for consideration of the joint resolution (H.J. Res. 20) providing for congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Department of Energy relating to “Energy Conservation Program: Energy Conservation Standards for Consumer Gas-fired Instantaneous Water Heaters”; providing for consideration of the joint resolution (H.J. Res. 35) providing for congressional disapproval under chapter 8 of title 5, United States Code, of the rule submitted by the Environmental Protection Agency relating to “Waste Emissions Charge for Petroleum and Natural Gas Systems: Procedures for Facilitating Compliance, Including Netting and Exemptions”; and providing for consideration of the concurrent resolution (H. Con. Res. 14) establishing the congressional budget for the United States Government for fiscal year 2025 and setting forth the appropriate budgetary levels for fiscal years 2026 through 2034.: 2025 — H.Res. 161 provides for House floor consideration of H.J. Res. 35, a CRA disapproval resolution targeting EPA’s Waste Emissions Charge for Petroleum and Natural Gas Systems (methane fee procedures, netting, and exemptions). (novelty: 2)
• 2026-07-06 — National Emission Standards for Hazardous Air Pollutants: Plywood and Composite Wood Products: 2025 — EPA finalized updated NESHAP MACT standards for Plywood and Composite Wood Products facilities (formaldehyde, mercury, dioxins, PAHs), resolving the 2007 remand of the 2004 rule and a petition on the 2020 Residual Risk and Technology Review. (novelty: 2)
• 2026-06-25 — Clean Ports for Commerce Act: 2025 — Clean Ports for Commerce Act (HR9483) introduced in the 119th Congress and referred to the House Committee on Transportation and Infrastructure, proposing clean-port-related emissions measures. (novelty: 2, status: introduced) (novelty: 2)
• 2026-06-02 — Modern, Clean, and Safe Trucks Act of 2026: 2026 — Modern, Clean, and Safe Trucks Act of 2026 introduced in the Senate and referred to the Committee on Finance, signaling legislative interest in updating commercial truck standards (likely including the heavy vehicle use tax and related emissions/safety provisions). (novelty: 2, status: introduced) (novelty: 2)
• 2026-07-02 — Federal Plan Requirements for Other Solid Waste Incineration Units That Commenced Construction on or Before August 31, 2020, and Have Not Been Modified or Reconstructed After August 29, 2025: EPA proposed a federal plan (2025) to implement revised emission guidelines for existing Other Solid Waste Incineration (OSWI) units in states or tribal areas that fail to submit approvable Section 111(d)/129 plans by June 30, 2027; applies to units that commenced construction on or before Aug 31, 2020 and are not modified/reconstructed after Aug 29, 2025. (novelty: 2)

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