There’s a new strategy in Colorado’s fight against dangerous ozone air pollution: Blame Utah.
Coal-fired power plants and oil and gas drilling in northeastern Utah are responsible for ozone drifting to the east into Colorado’s nine-county nonattainment zone for the pollutant, according to the Environmental Protection Agency.
The amount of ozone that Utah is pumping toward Colorado violates the federal “good neighbor” rules of the Clean Air Act, which have been used in the past to force Eastern states to clean up coal plants to help downwind states. The EPA rejected Utah’s State Implementation Plan (SIP) for cutting ozone in February and told the state to prepare more cuts, including adding expensive scrubbing equipment to a handful of coal power plants in Utah and Wyoming.
Utah’s legislature agreed something needed to be done and set aside $2 million – for legal fees to sue the EPA and avoid the extra cleanup.
“Utah is not being a good neighbor,” said Robert Ukeiley, Colorado senior attorney with the Center for Biological Diversity, a nonprofit that works extensively on air pollution issues and the Clean Air Act.
The neighbors, in the form of the Utah Attorney General’s office, declined to comment, citing the lawsuit Utah filed in February to block the EPA’s bad neighbor declaration. In voting to fund the lawsuit, Utah lawmakers argued the EPA ruling would force closures of vital power plants, though environmental groups say effective control equipment can greatly reduce the pollutants.
Colorado environmental groups want the Colorado state government to intervene with the EPA in favor of the Utah restrictions. Backing up the EPA should be part of Colorado’s overall ozone fight, which they say should also include tougher restrictions at home on Front Range oil and gas drilling and transportation emissions. It’s the equivalent of free money in the difficult battle to reduce ozone, which had been declining but then leveled off and began rising again in recent years.
“There’s an opportunity for Colorado to join in a lawsuit to help reduce pollution, but the Polis administration has decided not to,” Ukeiley said.
Colorado regulators said in a statement they are monitoring the good neighbor case against Utah.
“We have not joined EPA good neighbor suits in the past,” a Colorado Department of Public Health and Environment spokesperson said. “We are laser focused on continuing the work to protect clean air in Colorado for all.”
It’s too bad, Ukeiley said. States on the East Coast join such lawsuits frequently in order to bolster the case against their ill-behaving neighbor states.
“But Colorado never does that,” he said.
The EPA’s proposed restrictions on Utah, which the agency says would take effect in mid-March, are part of a sweeping effort to declare “good neighbor” sanctions for 26 states under the Clean Air Act. The EPA reduced the ceiling on cities’ ozone allowances in 2015 to 70 parts per billion, with some scientists arguing the limits should be far lower to protect human health.
An EPA fact sheet accompanying the good neighbor proposal says it will cut ozone-contributing nitrogen oxide by 29% from power generation across those states, saving lives, reducing asthma and preventing other respiratory illnesses. By 2026, the EPA says, the rules would eliminate up to 1,000 premature deaths, 2,400 hospital and emergency room visits and 1.3 million cases of asthma symptoms.
The EPA’s justification for the new good neighbor rulings, published in the Federal Register, says the agency’s well-established monitoring methods show Utah contributing more than the 1% threshold of regulated substances to other states.
“Its highest-level contribution is 1.29 parts per billion to Douglas County, Colorado,” the EPA said.
That number appears small, but the Colorado Air Quality Control Commission and the Regional Air Quality Council spend countless hours discussing strategies and policies to potentially shave a part or two per billion off summer ozone levels in the Front Range nonattainment area. Readings in recent summers have spiked above 80 ppb at some monitors.
Some recent policy efforts have focused on reducing ozone-causing emissions from small engine lawn and garden equipment, which state officials estimate contribute about 2.5 ppb to daily summer ozone. The Colorado oil and gas industry, seeking to head off further regulation, has pointed to the same state emissions list that attributes more than half of daily ozone to “background” sources, including naturally occurring ozone and precursors blown in from out of state, including the West Coast and Asia.
One of the EPA’s proposed solutions to ozone problems in other states has been a “cap and trade” program, where a state in violation of good neighbor policies must set an overall limit on emissions such as nitrogen oxide. Companies including power generators then decide what is the most efficient way for them to reach those limits, whether buying and installing scrubbing equipment or acquiring credits from other companies that are below their limits.
Environmental groups call the good neighbor rules some of the most effective tools the EPA has to combat ozone, and note that the 2023 EPA proposal for cap and trade adds in new sources to control. Those include engines used in pumping natural gas through pipelines, cement kilns, paper mills and oil and gas refineries.
“Those rules have saved thousands or tens of thousands of lives by reducing air pollution,” Ukeiley said.
If there’s any remaining good news for Colorado out of the EPA actions, it’s that Colorado is not among the 26 states the agency has declared to be a bad neighbor to someone else. You’re welcome, Kansas.
But Coloradans shouldn’t get smug, Ukeiley said, as long as the state fails to contain its own ozone problem.
“The EPA has not found us to be an upwind state,” he said. “We disagree with that.”