Senate blocks CRA bid to restore Colorado haze cleanup plan

The EPA's full disapproval of Colorado's regional haze plan was finalized and published in the Federal Register on January 26, 2026. Colorado had submitted the plan revision in May 2022 after years of stakeholder input. The plan included 13 voluntary source closure dates for coal-fired power plants, including an enforceable closure deadline for Nixon Unit 1 at the Ray D. Nixon Power Plant, which Colorado Springs Utilities had voluntarily proposed for inclusion in 2020.

The EPA cited two legal bases for the full disapproval. First, it said Colorado failed to provide required assurances that the Nixon Unit 1 closure deadline would not constitute an unconstitutional governmental taking of private property, because Colorado Springs Utilities had rescinded its closure consent in March 2025 after citing changing grid conditions. Second, the EPA raised reliability concerns, referencing a December 2025 Department of Energy emergency order requiring Craig Station Unit 1 to remain open for grid stability.

Environmental groups and the Colorado Attorney General challenged the EPA disapproval in the U.S. Court of Appeals for the Tenth Circuit. The National Parks Conservation Association and Sierra Club filed separate petitions arguing that the EPA's rationale was legally flawed and that Colorado's plan fully complied with the Clean Air Act. The Colorado AG argued in a public statement that the EPA's action was based on policy objections to coal plant closures rather than any legal deficiency in the state's submission.

Harvard's Environmental and Energy Law Program analyzed the case and found that the EPA's concern about the Nixon Unit 1 closure date was significant but contested. The utility, Colorado Springs Utilities, had voluntarily asked to be included in the closure plan in 2020 and only reversed that position five years later after changes in its assessment of grid conditions, raising questions about whether a state plan relying on a voluntary commitment could later be invalidated by the utility's change of mind.

The regional haze program under the Clean Air Act requires states to develop plans to reduce air pollution and improve visibility in national parks and wilderness areas designated as mandatory Class I federal areas. Rocky Mountain National Park and Colorado's other wilderness areas qualify as Class I areas. The program has two implementation periods, with states submitting revised plans on a rolling schedule.

Colorado's 2022 plan revision was broadly supported by state agencies, the utilities that proposed the closures, industry, and environmental groups before Colorado Springs Utilities reversed course. The EPA had initially proposed only a partial disapproval in July 2025 but ultimately issued a full disapproval in January 2026, preventing any of the plan's provisions from taking effect.

With the EPA disapproval in place and the Senate CRA vote failing, Colorado must submit a new revised SIP within two years that satisfies EPA requirements, or the EPA will issue a Federal Implementation Plan imposing its own pollution controls on Colorado sources. A FIP represents a significant override of state environmental authority, removing Colorado's ability to choose which sources face controls and under what timeline.

Democrats, including Bennet, argued that the EPA's disapproval was motivated by the Trump administration's broader policy of protecting coal plants rather than any genuine legal concern. The EPA's own press release stated that shutting down coal plants is not necessary to meet regional haze requirements, a policy position that critics argued went beyond the agency's statutory role of evaluating whether state plans comply with the Clean Air Act.

Sen. Bennet was running for Colorado governor at the time of the vote, adding a political dimension to his CRA resolution. By forcing Republicans to vote on whether to override the EPA's rejection of Colorado's clean air plan, he created a campaign issue in a state where energy and environmental policy are central electoral concerns. Colorado has been transitioning toward renewable energy, and coal plant retirements have been supported by bipartisan local coalitions.

E&E News reported that Democrats used the back-to-back CRA votes on April 29 to spotlight energy affordability and environmental protection issues simultaneously, framing them as cases where the Senate Republican majority was blocking state-level decisions on energy policy and immigrant worker rights.

The December 2025 Department of Energy emergency order requiring Craig Station Unit 1 to remain open was issued under section 202(c) of the Federal Power Act, which authorizes emergency orders to prevent grid reliability failures. The DOE cited changing grid conditions in the Colorado region. The combination of the DOE order and the EPA disapproval effectively froze two separate coal plant retirement timelines in Colorado through overlapping federal actions by different agencies.

Environmental advocates argued that the grid reliability rationale was overstated and that the utilities and state grid operators had already planned around the coal plant retirements. They noted that the EPA had initially proposed only a partial disapproval, targeting the Nixon Unit 1 closure date, and only escalated to a full disapproval in the final rule.