Dive Brief:
- The U.S. EPA on Jan. 27 proposed phase one of its reconsideration of the Good Neighbor Plan, which was adopted in 2023 and required upwind states to limit emissions from power plants and industrial facilities so downwind states could meet Clean Air Act requirements.
- Under phase one, the agency would approve eight State Implementation Plans pertaining to the 2015 eight-hour ozone National Ambient Air Quality Standards. These SIPs were disapproved under the Biden Administration’s interpretation of the Good Neighbor Plan.
- A variety of facilities are affected by the rule, including power plants, natural gas pipelines, cement and cement product manufacturing plants, iron and steel mills, glass and glass product manufacturing plants and others.
Dive Insight:
According to the EPA, the Clean Air Act’s “good neighbor” or “interstate transport” provision requires that each state’s SIP take adequate steps to prohibit emissions from within the state from interfering with maintenance of the NAAQS in other states.
The agency’s latest proposal would effectively mean that the covered states, including Alabama, Arizona, Kentucky, Minnesota, Mississippi, Nevada, New Mexico and Tennessee, have fulfilled their obligation to avoid significantly interfering with other states’ ability to meet or maintain the 2015 eight-hour ozone NAAQS.
The proposal “demonstrates the Trump EPA’s commitment to advance cooperative federalism and recognizes the important responsibility EPA shares with our state air agency partners to ensure clean air for all Americans,” the agency said in a press release.” By contrast, it said, the Biden administration disapproved or corrected parts of the SIPs for several states, claiming they did not adequately control ozone emissions that travel across state lines.***
“These decisions were made despite these states properly using EPA-supported modeling and thresholds to demonstrate they were not interfering with the attainment of the NAAQS in other states,” the agency said.
It added that the Biden administration should not have even finalized the Good Neighbor Plan, a 2023 rule that imposes strict emission controls for power plants, natural gas pipelines and a variety of other facilities used by many industries in 20 states. The rule came “despite 21 states demonstrating they did not need to address emissions activity within the state in order to not interfere with other states' ability to meet [Clean Air Act] standards,” the EPA said.
If the phase one action is finalized, the EPA also intends to withdraw proposed SIP disapprovals issued for five other states in February 2024 under President Joe Biden. These include Arizona, Iowa, Kansas, New Mexico and Tennessee.
In June 2024, the U.S. Supreme Court held that the Good Neighbor Plan could not be enforced pending litigation in the U.S. Court of Appeals for the D.C. Circuit. In June 2025, the Supreme Court found that states can contest EPA’s earlier decision to first disapprove state good neighbor plans in regional appellate courts instead of the U.S. Court of Appeals for the District of Columbia Circuit, which is the usual venue for bringing challenges to nationally applicable rules.
In an email, Michael Davin, senior director of energy and resources policy for the National Association of Manufactuers, praised the EPA’s reconsideration of the Good Neighbor Plan.
“The previous administration’s rule would have required certain states to mitigate interstate ozone emissions from power plants and other industrial sources, risking significant negative effects on energy reliability and prices, economic growth and jobs,” he said. “The EPA’s actions to approve these eight states' plans will help ensure the full economic costs of the rule, as well as the rule’s workability, are taken into account.”
However, the Environmental Defense Fund and other environmental groups have said the proposal would endanger human health by reversing the EPA’s prior determinations that certain states have failed to adequately control pollution.
When it promulgated the rule, the Biden administration projected it would result in a 15% reduction in nitrogen oxide levels from a 2019 baseline if implemented.
“The Trump EPA is turning its back on millions of Americans who are suffering from pollution they did not create and cannot control by allowing states out of their legal obligation not to dump pollution on their downwind neighbors,” Noha Haggag, a senior attorney for clean power at EDF, said in a press release. “These protections are vital because smog does not respect state lines.”
The proposal comes as the EPA reconsiders dozens of regulations promulgated by the Biden administration. For example, the agency recently moved toward changing a NAAQS standard for fine particulate matter that manufacturers have criticized as unachievable.
At the same time, Congressional Republicans are seeking to modify certain environmental laws in ways that are favorable to industry, such as by making it easier to obtain permits for infrastructure projects.***
