EPA tackles toxic power plant emissions

By Sean Reilly | 04/05/2023 01:47 PM EDT

The proposal could become the first significant update in a decade to toxics regulations for coal-fueled power and reverse a Trump-era decision.

Smoke blows from the Four Corners Power Plant

Smoke blows from the Four Corners power plant in Waterflow, N.M., near the San Juan River in April 2006. Susan Montoya Bryan/AP Photo

EPA would crack down on power plants that burn a notoriously dirty form of coal while more broadly curbing industry releases of arsenic and other hazardous metals, under a draft Clean Air Act rule rolled out Wednesday.

If made final, the proposal would mark the first significant update to air toxics regulations for the coal-fueled power sector in a decade. It would also reverse a 2020 Trump-era decision that no changes were needed to what are formally known as the Mercury and Air Toxics Standards (MATS).

“By leveraging proven, emissions-reduction measures available at reasonable costs and encouraging new, advanced control technologies, we can reduce hazardous pollution from coal-fired power plants, protecting our planet and improving public health for all,” EPA Administrator Michael Regan said in a statement.


Most notably, the draft rule would end a loophole for electricity plants — primarily in Texas and North Dakota — that burn lignite, a high-polluting form of coal. Under current standards, those plants must meet a mercury emission limit more than three times as high as that for other coal-fired plants. EPA has now decided that lignite-fueled facilities are technologically capable of meeting the stricter limit.

“We are leveling the playing field across the entire coal fleet for mercury standards,” acting EPA air chief Joe Goffman told reporters on a conference call Wednesday morning.

The draft rule would also tighten limits on a type of particulate matter that serves as a stand-in for releases of nickel, arsenic and other metals besides mercury. Most plants can already meet that regimen, Goffman said. Other features of the proposed rule, which EPA hopes to make final by next March, include a requirement for continuous emissions monitoring in place of periodic “stack tests.”

The proposal’s release came the day after environmental, civil rights and public health groups rallied outside EPA headquarters to press for faster action on a variety of power plant rules (E&E News PM, April 4). An agency spokesperson did not respond to a Tuesday email asking whether that rally — which EPA knew well in advance was coming — had any effect on the timing of the then-pending proposal’s release.

EPA plans a public hearing on the proposal, which will carry a 60-day cutoff for written feedback when published in the Federal Register.

The original standards, issued in 2012, rank among the most consequential Clean Air Act rules in EPA history, with estimated health benefits in the tens of billions of dollars.

The projected impact of the proposed update would be modest by comparison. Despite the crackdown on lignite-burning plants, for example, the draft rule would cut the power sector’s overall emissions of mercury — which last year amounted to 2.9 tons — by just 82 pounds by 2035, according to the EPA forecast.

The expected effect on other pollutant emissions would be more substantial during that time. Releases of sulfur dioxide would fall by 8,800 tons, the forecast shows, with emissions of smog-forming nitrogen oxides dropping by almost the same amount. EPA is also seeking input on more stringent alternatives to its current proposal; in prepared statements, some advocacy groups immediately called on the agency to pursue them.

“We urge EPA to strengthen this proposal significantly to decrease emissions of mercury, toxic metals and other emissions that cause irreversible harm,” said Harold Wimmer, president and CEO of the American Lung Association.

Coupled with other EPA regulations targeting coal-fired plants, however, even the current proposal could add to economic pressures that have already prompted many to close.

The Biden administration “continues to wage war on coal and affordable, reliable energy by issuing unnecessary regulations intended to drive down electricity production from our nation’s baseload power resources,” West Virginia Sen. Shelley Moore Capito, the top Republican on the Senate Environment and Public Works Committee, said Wednesday.

But EPW Chair Tom Carper (D-Del.) welcomed the proposal, saying it would build on progress already made “to better protect communities.”

Costs and benefits

On a yearly basis, EPA expects the proposal to deliver net benefits of $300 million to $350 million. Over a decade, the estimated annual compliance cost would average $23 million to $33 million, according to the EPA forecast.

At the Edison Electric Institute, a power industry trade group that had previously argued against any changes to the status quo, a senior official struck a noncommittal stance on the draft rule.

While the institute is still reviewing the details, “we look forward to continuing to work with Administrator Regan and his team as they finalize the rule to ensure that implementation of the standard is consistent with our industry’s ongoing clean energy transformation” said Emily Fisher, the institute’s general counsel and executive vice president of clean energy.

Mercury is a potent neurotoxin that can damage babies’ brain development. In the organic form known as methylmercury, it also builds up in fish, making it particularly dangerous to subsistence fishers.

After decades of delay, EPA issued the Mercury and Air Toxics Standards in 2012. Under the Clean Air Act, EPA had to then conduct a review within eight years to determine whether any “residual risk” remained to public health, as well as whether technological advances made further emissions reduction feasible.

Under appointees of then-President Donald Trump, EPA in 2020 opted against any changes. In its new proposal, agency officials conclude that the health risks are acceptable while identifying additional controls “to reduce hazardous air pollutants,” Goffman said.

In an earlier about-face from another Trump-era decision that set the stage for the proposal’s release, EPA in February revived the legal basis for the standards by reasserting that it was “appropriate and necessary” to regulate hazardous pollutant releases from coal- and oil-fired power plants.

Under Trump, EPA also carved an exemption from MATS’ full requirements for four plants in West Virginia and Pennsylvania that burn coal refuse.

As E&E News previously reported, one of those facilities is supplied by the family business of Senate Energy and Natural Resources Chair Joe Manchin (D-W.Va.) (Climatewire, Feb. 2, 2022).

The new proposal does not deal with that exemption; EPA plans to address it in a separate rulemaking, a spokesperson said.