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An Unlikely Foe Is Slowing the Fight Against Wildfire Pollution

The Clean Air Act isn’t helping.

Richard Nixon and wildfire smoke.
Heatmap Illustration/Getty Images, Wikimedia Commons

Wildfire smoke is making air pollution in the United States a lot worse, as anyone in New York City last week can attest. Yet the regulatory tools that have done so much to reduce emissions from cars and smokestacks may actually be getting in the way of effectively managing forests in order to prevent massive, out of control fires.

The increasing importance of wildfire smoke, and the structural policy changes required to fight it — from overhauling forestry practices to worldwide reductions in greenhouse gas emissions — may require a rethinking of how public policy is supposed to protect people from pollution.

Catalytic converters in cars have visibly cleared the air even in the most traffic-jammed cities; getting rid of lead in gasoline has made children smarter; efforts to fight acid rain were so successful that the paucity of it is now seen as a reason to ignore current environmental problems. But all these efforts were aimed at limiting emissions from particular sources, like factories and vehicles, not fires that consume tens of thousands of acres across a mixture of federally managed and privately held land.

This is the paradigm of pollution policy, Kirsten Engel, a law professor at the University of Arizona, told me. Policymakers go to “particular point sources” like factories, cars, and refineries to keep the pollutants they generate below national standards. “Of course wildfires don’t fit that paradigm," she said. “They’re not a point source that’s easily controlled.”

Under the Clean Air Act, states and regions are mandated to meet National Ambient Air Quality Standards, levels of six air pollutants that the EPA sets out — including the tiny particulates that wildfires spew out, known as PM2.5. But many of those wildfire days are essentially not counted under the Clean Air Act rules, as they’re ruled to be “exceptional.” The logic behind this framework is that states should not be held responsible for emissions they can’t reasonably control. Without the exceptional event framework, extreme wildfire events could essentially force mass shutdowns of industry in regions affected by it.

But the framework is being pushed to its limits. Utah State University researcher Liji David found that, between 2000 and 2017, “Wildland fires were the primary driver for PM2.5 exceptional events,” with regions in the western United States having the most such events. This means that a growing source of a form of pollution that’s supposed to be limited under the Clean Air Act is not even falling within the law’s purview. And this is having dramatic effects on air pollution nationally, to the point of partially reversing the gains under the Clean Air Act.

According to research by Stanford economist Marshall Burke and others, “since 2016, wildfire smoke has significantly slowed or reversed previous improvements in average annual PM2.5 concentrations in two-thirds of U.S. states, eroding 23% of previous gains on average in those states (equivalent to 3.6 years of air quality progress) and over 50% in multiple western states.”

Research by Marissa Childs, who contributed to the Burke paper, found that some Western areas “saw decadal increases in an annual smoke PM2.5...comparable in absolute magnitude to the reduction in PM2.5 brought about by the Clean Air Act in the US.”

The solution, explained Michael Wara, a researcher at Stanford, is a complete rethinking of forestry, indoor air quality, and of course, emissions reductions. This would entail overhauling forest management, including a massive increase in prescribed burns on federal, state, and private land. These intentional fires can remove fuel from a forest floor that would spark a larger, uncontrolled fire. Doing controlled burns adequate to the scale of the wildfire challenge would require essentially a total reversal of about a century of forest management policy in the United States.

Here the Clean Air Act isn’t merely silent, as it can be with wildfire, but may be actively inhibiting good policy. Whereas wildfire smoke can and often does get waived by states under the exceptional event framework, smoke from a prescribed burn can often is still counted or the prescribed burns are not done at all in order to maintain compliance with air quality standards. Advocates for controlled burns argue that the net amount of smoke — and therefore pollution — would be lower with a more aggressive and permissive policy for prescribed burns.

According to a Government Accountability Office report, officials at the Department of Interior want more leeway to conduct prescribed burns but feel inhibited by the EPA's use of the exceptional events rule and air quality standards. Land management officials also warned that their hands will be increasingly tied in areas that are already above or near the upper limit of air quality standards, particularly, as the EPA has proposed, if those standards become more strict.

One legal scholar has argued that the exceptional events designation should be flipped on its head entirely, and that the Environmental Protection Agency “should only exempt pollution from wildfire smoke when states take steps to mitigate extreme and increasing wildfire risk through effective land management with prescribed burns.”

“The EPA is philosophically at this point still not convinced of that idea,” Wara said.

Even beyond the rules around exceptional events, Wara said, more funding and a different culture of forest management are needed. “We don’t have a workforce, we don’t have a budget, we don’t have a career line that would support this kind of work. If you’re going to treat land in any way at the scale we’re talking about, we need an army,” Wara said.

Beyond wildfire prevention, there’s also the immediate responses to bad air, namely well insulated homes and workspaces with adequate filtration. “In the meantime you can’t let people die,” Wara said. “People need protection,” including air filters for seniors, who are at a higher risk of negative health outcomes from smoke.

“The most basic idea of the Clean Air Act and all environmental laws is to protect people and protect public health,” Wara said. “It’s not climate change, it’s not cute little creatures. The big political movement that drove change was to protect people. And I think we need to get back to that basic idea when it comes to the Clean Air Act.”

Matthew Zeitlin profile image

Matthew Zeitlin

Matthew is a correspondent at Heatmap. Previously he was an economics reporter at Grid, where he covered macroeconomics and energy, and a business reporter at BuzzFeed News, where he covered finance. He has written for The New York Times, the Guardian, Barron's, and New York Magazine.


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