EPA soot rule puts new pressure on fossil fuels

By Sean Reilly | 02/07/2024 01:28 PM EST

The stricter limit is “a game changer” that will “shape the world our children will inherit tomorrow,” EPA Administrator Michael Regan said.

Emissions rise from smokestacks.

Emissions rise from the smokestacks at the Jeffrey Energy Center coal power plant as the suns sets Sept. 18, 2021, near Emmett, Kansas. The Biden administration is setting tougher standards for deadly soot pollution. Charlie Riedel/AP

In a historic about-face, EPA has toughened one of its most far-reaching air pollution standards in a move expected to save thousands of lives and add to the long-term pressure for a shift away from fossil fuels.

Under a final rule issued Wednesday morning, the agency chopped the annual exposure limit for the fine particles often dubbed soot for the first time in more than a decade.

The stricter limit is “a game changer” that will “shape the world our children will inherit tomorrow,” EPA Administrator Michael Regan told reporters on a Tuesday call previewing his decision.


The new rule sets an average yearly soot exposure standard of 9 micrograms per cubic meter of air, down sharply from the current threshold of 12 micrograms.

In 2032, when the tighter benchmark is supposed to be fully implemented, EPA expects it to prevent up to 4,500 premature deaths, according to an official forecast. The projected health benefits by that point will be at least $22 billion and as high as $46 billion, far outpacing the estimated compliance costs of about $600 million, the forecast shows.

The states with areas that could have trouble meeting the new requirements include California, Arizona, Pennsylvania and Texas, according to air quality monitoring data from recent years. While industry advocates predict that the stronger limit will hurt the economy by tightening permitting requirements for new plants and other projects almost immediately, Regan noted that the nation’s gross domestic product has grown by more than half since 2000 even as airborne soot concentrations have fallen sharply. More broadly, EPA likely won’t complete initial compliance decisions until 2026, followed by years more for cleanup plans to take effect.

The rule, which is certain to be challenged in court, had been long expected and is likely to rank among the most significant of the Biden-era EPA. In a blitz of news releases, environmental lobbies, business groups and members of Congress swiftly staked out opposing sides.

The rule “is the latest in a growing list of short-sighted policy actions that have no scientific basis and prioritize foreign energy and manufacturing from unstable regions of the world,” said Will Hupman, vice president of downstream policy at the American Petroleum Institute, an oil and gas industry trade organization. “As we will review the final standard, we will consider all our options.”

But at the Natural Resources Defense Council, President and CEO Manish Bapna said that soot puts “tens of millions of Americans at risk, disproportionately harming low-income communities and people of color.”

“This will help save lives today and improve the health of generations to come,” Bapna siad.

Still, the new annual threshold stops short of the 8 micrograms standard that was at the low end of a range of recommendations endorsed last year by most members of an EPA advisory committee.

While that stricter limit would have yielded dramatically higher health benefits than the 9 micrograms standard, it also carried much steeper compliance costs, according to an earlier analysis. The new rule also breaks from the advisory committee’s majority findings by retaining the daily exposure threshold of 35 micrograms per cubic meter of air, instead of slicing it to at least 30 micrograms. A microgram is one-millionth of a gram.

A 2022 Environmental Defense Fund report estimated the total yearly number of premature deaths stemming from soot exposure at 120,000, with older Black Americans far more vulnerable. While Chitra Kumar of the Union of Concerned Scientists praised EPA for going ahead with the new rule in the face of intense industry resistance, she added that “the science is clear that the agency’s work is not yet done.”

“Too many people’s health is still at risk,” said Kumar, the research and advocacy group’s managing director for climate and energy programs.

Soot is technically known as fine particulate matter, or PM2.5, because the microscopic specks and droplets are no bigger than 2.5 micrometers in diameter, or roughly one-hundredth the size of a grain of table salt. With its ability to penetrate deep into the lungs and even infiltrate the bloodstream, it is tied to a wide variety of cardiovascular and respiratory ills, with people of color disproportionately vulnerable.

Direct and indirect sources of soot pollution are similarly diverse, encompassing everything from roadside dust to diesel-powered trucks to coal-fired power plants.

Although the new standard does not directly target industrial- or transportation-related sources, state and local regulators in out-of-attainment areas could have to press them for additional emission cuts,. Meanwhile, EPA predicts that other forthcoming tailpipe and power plant regulations will aid in compliance.

The stricter requirements will do nothing, however, to counter a massive wellspring of soot that is outside of immediate human control: the vast plumes of smoke spawned by larger and longer-lasting wildfires linked to climate change.

A historic rule

Under the Clean Air Act, particulate matter is among a half-dozen pollutants covered by National Ambient Air Quality Standards that EPA must periodically revisit to ensure that they mesh with the latest research into their health and environmental effects.

The rule released Wednesday marks the first time since 2015 that EPA has toughened any of those standards.

It also caps an almost decadelong regulatory battle and signals an unprecedented reversal of EPA’s decision under former President Donald Trump to leave soot limits unchanged.

Following an accelerated review that critics viewed as politicized, then-EPA Administrator Andrew Wheeler in late 2020 bypassed the conclusions of his career staff in opting to keep the 12 micrograms standard in place. Six months later, Regan, an appointee of President Joe Biden, announced plans to revisit that decision on the grounds that more aggressive action might be needed to adequately protect public health.

That step is extremely rare. Some 15 years have passed, for example, since EPA under then-President Barack Obama launched a reconsideration of an earlier reset of a key smog standard, only to later see it blocked by the White House for fear of the potential economic fallout.

While that episode infuriated public health advocates, it turned Obama into an improbable model for congressional Republicans and business lobbies who wanted Biden to similarly pull the plug before the soot standards reconsideration was completed. Joining them were two Democratic governors — Andy Beshear of Kentucky and Laura Kelly of Kansas — in Republican-leaning states.

They used similar language in recently urging Biden to start over, according to separate letters.

There is thus far no public indication that the White House seriously considered those pleas. The new rule is the first time in Clean Air Act history that one administration has overruled a predecessor’s decision in resetting an ambient air quality benchmark, an EPA spokesperson confirmed.

The agency last toughened soot standards in 2012. The newly announced final rule follows a draft version released in January 2023 that proposed an annual exposure threshold of 9 to 10 micrograms. In perhaps the new rule’s most directly visible impact, EPA is also revising the color-coded Air Quality Index that warns the public when pollution levels are becoming unhealthy.

The fight is set to continue in Congress, where the Republican-controlled House has preemptively approved a fiscal 2024 spending bill that would block the more stringent standard from taking effect. On the other side of the Capitol, Sen. Shelley Moore Capito (R-W.Va.), the ranking member on the Senate Environment and Public Works Committee, last year introduced legislation to stop EPA from moving ahead until the end of the decade.

The bill has not advanced out of committee. In a statement, Capito predicted that the 9 micrograms standard would hamstring manufacturing and energy projects across the country and was “simply not realistic to meet.”

EPW Chair Tom Carper (D-Del.) countered that EPA used sound science in crafting the new rule and that it helps ensure that “every American breathes clean air — no matter where they live, work, or play.”

Reporter Andres Picon contributed.