December's New Chemicals: EPA Receipt and Status Log

2026-19071, Partial Repeal of the Carbon Pollution Standards for Fossil Fuel-Fired Electric Generating Units

The EPA is rolling back most of the 2024 rules that limited carbon pollution from fossil fuel power plants. This change affects coal and gas plants by easing some strict limits on emissions and carbon capture technology. The new rules kick in on November 16, 2026, potentially saving money for power plants but raising questions about pollution control.

2026-19072, Rescission of the Greenhouse Gas Findings for Fossil Fuel-Fired Power Plants and Repeal of Regulations for Power Plant Greenhouse Gas Emissions Under Clean Air Act Section 111

The EPA is proposing to cancel all greenhouse gas rules for fossil fuel power plants, saying the law doesn’t let them regulate these emissions for climate reasons. This change affects power plants across the U.S. and could impact future pollution limits and costs. Comments on this proposal are open until November 2, 2026, so now’s the time to speak up!

2026-18317, Updated Definition of “Waters of the United States”

The purpose of this supplemental notice of proposed rulemaking is for the U.S. Environmental Protection Agency (EPA) and the Department of the Army ("the agencies") to supplement and seek additional comment on certain aspects of an earlier proposal, published on November 20, 2025, to revise the regulations defining the scope of waters federally covered under the Clean Water Act in light of the U.S. Supreme Court's 2023 decision in Sackett v. Environmental Protection Agency. As stated in the agencies' November 20, 2025 Notice of Proposed Rulemaking (NPRM), the agencies intend for this rulemaking to provide greater regulatory certainty and increase Clean Water Act program predictability and consistency by clarifying the definition of "waters of the United States." After consideration of the public comments received on the NPRM, the agencies are issuing this notice to supplement the NPRM with additional regulatory options on certain aspects of the proposed rule.

2026-14112, Amendments and Nonconformance Penalties for Model Year 2027 and Later Heavy-Duty Highway Engines and Amendments to Inducement Provisions for SCR-Equipped Diesel Engines

Starting with model year 2027, the EPA is updating rules for big truck engines to make sure they last longer and pollute less. They’re also letting engine makers pay penalties if their engines don’t meet standards, and tightening rules for special pollution-control systems on diesel engines. These changes affect truck and engine makers and kick in soon, with public feedback due by August 29, 2026.

2026-13667, Minor New Source Review Program Air Permitting Public Participation Requirements for State Implementation Plans

The EPA wants to give states more freedom to decide how much public input is needed when approving small air pollution sources or changes. This means local air agencies can tailor public participation to fit their community’s needs while still protecting air quality. If you’re involved in air permits, watch for comment deadlines and possible virtual hearings this summer!

2026-13263, Revisions To Establish the Sixth Unregulated Contaminant Monitoring Rule (UCMR 6) for Public Water Systems

The EPA is rolling out the sixth Unregulated Contaminant Monitoring Rule (UCMR 6) to check for new, sneaky chemicals in public drinking water. Big water systems serving 3,300+ people and some smaller ones will test for 30 different contaminants, including certain PFAS and pesticides, to keep our water safe. Comments and feedback are open until late August 2026, and the EPA will host fun online meetings to chat about the plan!

Previous: 2025-02993, Certain New Chemicals or Significant New Uses; Statements of Findings for September, October, November, and December 2024

The EPA reviewed new chemicals and big changes to existing ones from September to December 2024 and found they’re unlikely to harm people or the environment. This update affects companies making or using these chemicals, letting them move forward without extra delays or costs. If you’re in the chemical business, keep an eye on these findings to stay in the clear and on schedule!

Next: 2025-02995, Certain New Chemicals; Receipt and Status Information for January 2025

The EPA is sharing updates on new chemicals they received and reviewed in January 2025. Companies submitting new chemical info, test data, or exemption requests should note the March 26 deadline to comment. This keeps everyone in the loop about what’s being checked before chemicals hit the market, helping protect people and the planet without slowing down innovation.