Introduction

Key findings: It’s not just L.A.: From big cities to suburbs to rural Utah, many places fail EPA’s smog standards. The EPA places the cost of reducing lung-damaging ozone at $15 billion a year. The National Association of Manufacturers says $140 billion. Americans get no air-quality warnings about a host of bad-ozone days. EPA’s science advisers have said since ’06 that U.S. ozone standards don’t protect health. Current U.S. smog standard, set in 2008, is the first one that’s stricter than the original limit set in 1971.

RANDLETT, Utah — Mountains sweep up from a landscape of red dirt and brown scrub. Pump jacks nod, pulling oil and gas from the ground. Deer dart toward a river. Trucks swish by, a few at a time, past the Ute Indian reservation.

It’s an unlikely place to find ozone levels that sometimes rival those of smoggy Los Angeles.

Too-high ozone, it turns out, bedevils communities across the United States. It’s not limited to the urban centers that have struggled for decades to reduce the lung-damaging air pollutant, created when nitrogen oxides and volatile organic compounds bake in the sun.

There’s ozone above the federal standard in smaller cities such as Cincinnati, Ohio, and Middletown, Connecticut. Because the stuff doesn’t stay put, it’s often worse in suburbs than car-clogged downtowns. And it’s over the threshold in parts of the Mountain West, exactly where you’d expect the air would be cleanest.

But even that fails to capture the full picture. For almost a decade, the U.S. Environmental Protection Agency’s independent scientific advisory committee of researchers and doctors has said the nation’s ozone standard is too lenient, a point of view backed by the American Academy of Pediatrics and other health groups.

That means people in a wide swath of the country breathe air that doesn’t violate any rules — and thus doesn’t trigger any warnings — and yet, according to research, is unhealthy. That’s particularly true for the young, the elderly, people with lung diseases and outdoor workers. As ozone rises, even to levels below the EPA’s 75-parts-per-billion threshold, studies have found increased asthma attacks and respiratory-driven hospital visits. There’s also growing evidence that ozone can affect the heart, increasing the risk of cardiac arrest.

“The science is showing how much more harmful ozone is than we previously thought,” said Janice Nolen, assistant vice president of national policy for the American Lung Association, which sued the EPA to press the agency to act.

The EPA’s advisory committee has said since 2006 that the standard should be between 60 and 70 ppb. In November, the EPA proposed a range of 65 to 70 ppb, saying it would save both medical costs and lives.

The geography of smog

The U.S. Environmental Protection Agency wants to tighten its standard for ozone, the lung-damaging gas in smog. It’s considering a range of 65 to 70 parts per billion, any part of which would put a significantly broader swath of the country out of compliance, requiring government agencies and industry in those places to step up pollution-control efforts. This map shows which counties measured ozone levels below and above the proposed limit, including which areas topped the current 75 ppb standard, during 2011-2013. Click on counties for more information.

Ozone levels in parts per billion 65 ppb or less Between 66 and 75 ppb Greater than 75 ppb

Source: U.S. Environmental Protection Agency

“There are millions of Americans who suffer from asthma, or their kids do,” Janet McCabe, acting assistant administrator for the EPA’s Office of Air and Radiation, said in an interview. “The American people are entitled to know whether their health is at risk based on the amount of ozone in the air.”

A final rule is due by October 1.

The EPA’s proposal turned a years-long cold war into a hot one. Tightening the rule by just 5 ppb could cost certain industries billions of dollars a year to better rein in ozone-causing emissions.

Those pollutants come from a variety of activities that make modern society tick. Car tailpipes. Power plants. Factories. Refineries. Natural gas wells. Paints and other consumer products. Whenever the EPA proposes new ozone standards, the pushback is rapid.

The National Association of Manufacturers said the rule would be “the most expensive regulation ever imposed on the American public.” A U.S. Chamber of Commerce official testified in January that the proposal could cause “potentially devastating economic and employment impacts.” The American Petroleum Institute insisted that the current standards already protect public health.

Businesses haven’t made the same arguments in Canada, which has a voluntary 63-ppb standard. Much of that country has reduced ozone levels below the range under consideration here. But the statements from American industry — especially predictions of economic devastation — echo every U.S. ozone battle for the past four decades.

Not every old argument has been resurrected. No one seems to be seriously suggesting this time, as the American Petroleum Institute did in the 1970s, that the major polluters are trees.

But now, with ozone well below where it was in those years, trade groups and some states say future reductions will be far more difficult.

“What we’re bumping up to in the West especially is … we get things in from California, we get a lot of tropospheric ozone coming in from Asia, and so if EPA puts that ozone level down towards 60 ppb, we could wipe out all human activity and we still would have pretty high ozone,” said Kathleen Sgamma, vice president of government and public affairs with the Western Energy Alliance, an oil-and-gas industry group.

McCabe said the EPA doesn’t ask high-ozone communities to stop growing and will work with areas that have unique challenges. The National Association of Clean Air Agencies, which represents the officials in 41 states and 116 localities who handle ozone efforts, endorsed a tighter standard this year.

But the last time the EPA considered taking this action, it was staved off by intense lobbying. There’s plenty of that going around again.

Fourteen of the companies and groups that consistently lobbied Congress, the EPA or both on ozone in the past two years have publicly stated their positions on a tighter standard. Only two — the lung association and the League of Conservation Voters — are for it. The rest — business interests, largely trade groups representing manufacturers and energy firms — are against it, according to a Center for Public Integrity analysis of federal disclosure data.

“We absolutely at this point are urging the EPA and anybody else who will listen to us to keep the current standard,” said Ross Eisenberg, vice president of energy and resources policy at the National Association of Manufacturers, which hears about regulatory delays and high expenses from members in ozone “nonattainment” areas. “At a time when … we’re having a manufacturing comeback largely because of energy, this just seems like the wrong way to go.”

A stricter standard could affect almost every state. The EPA says 358 counties had ozone levels in recent years that would violate a 70-ppb rule, about two-thirds of which are out of attainment with the current standard. At 65 ppb, the number rises to 558 counties.

Under the Clean Air Act, the EPA can freeze federal highway funds and impose other sanctions on areas that exceed health standards. But regions need only to submit plans and take steps toward achieving goals. McCabe said she expects many communities will be able to push their ozone below the threshold just by reaping the benefits of already enacted federal rules. A major one is a 2017 change in fuel standards.

“As my lungs got worse, the high ozone would affect them more and more. It would be like going outside on a subzero day — my lungs would just freeze up.” Daniel M. Dolan-Laughlin, a retired railroad executive

Daniel M. Dolan-Laughlin, a Chicago-area resident who has testified in favor of clean-air regulations, said high ozone made it increasingly hard for him to breathe as his lung disease worsened. He received a double lung transplant in 2011. Even now, he wears a mask if he must go out when ozone levels climb. (Courtesy of the American Lung Association)

Ozone isn’t something most people worry about. It’s confusing, for one. Up in the stratosphere, ozone is good, creating a layer that protects against ultraviolet radiation. It’s the stuff down at breathing level that’s bad, irritating the lungs and — research suggests — inflaming the blood vessels.

On top of that, it’s invisible. Only when it mixes with particle pollution does it pop into view as smog and offer a visual cue that something’s wrong with the air.

But Daniel M. Dolan-Laughlin pays close attention to ozone levels near him. He’s had to ever since chronic obstructive pulmonary disease began making everyday activities difficult in the 1990s.

“As my lungs got worse, the high ozone would affect them more and more,” said Dolan-Laughlin, a retired railroad executive who lives in a suburb of Chicago.

His disease made it increasingly hard to breathe, forcing him into early retirement in 1994 and later onto oxygen from a tank. Even with the oxygen, he couldn’t go outside when ozone levels rose.

“It would be like going outside on a subzero day,” he said. “My lungs would just freeze up.”

Dolan-Laughlin received a life-saving double lung transplant in 2011. Now he can walk up stairs without pausing every few steps to gasp. He’s climbed several mountains, in fact. But he won’t go out on bad ozone days without a mask.

Dolan-Laughlin, who has testified at EPA hearings in favor of a variety of clean-air rules, hopes the agency will tighten its ozone standard.

“I’m a strident capitalist,” he said, “but I’m also an environmentalist just out of common sense.”

Dianne LaFaver, a teacher who lives in the Dallas-Fort Worth metroplex, an ozone-challenged region, also wants a tighter standard.

LaFaver’s daughter, 22-year-old Laura Day, has asthma. Before Day left the area for college, her mother twice had to rush her to the emergency room on high-ozone days.

“She hadn’t been exercising, which was the normal trigger,” LaFaver said. “She hadn’t been stressing herself. We were just in the car. … At the emergency room, they were saying they were having lots of visits.”

Dr. Alfred Munzer, a lung-disease specialist who retired last year from Washington Adventist Hospital in Takoma Park, Maryland, saw 40 years’ worth of patients affected by ozone. There were the asthma attacks triggered by it — ozone causes spasms in the respiratory tract — and the infections that cropped up a day or two later because the pollutant interferes with the lungs’ ability to cleanse themselves, he said.

“There really is, as far as I know, no really safe level of ozone,” said Munzer, a former president of the American Lung Association.

The American Academy of Pediatrics has warned that children are more susceptible to ozone’s effects because their bodies are still developing. The EPA’s proposal, the group said in November, is “long overdue.”

Pumps suck in air through this funnel atop an air-monitoring station in Roosevelt, Utah, to test for ozone levels. (Jamie Smith Hopkins/Center for Public Integrity)

The politics of ozone

That’s also the message coming from the EPA’s Clean Air Scientific Advisory Committee Ozone Review Panel, whose 20 scientists and doctors are largely drawn from universities.

Last year panel members unanimously recommended tightening the ozone standard. While they said a range of 60 to 70 ppb would be better than the current threshold, they warned that the upper end might not “protect public health with an adequate margin of safety.”

The panel unanimously recommended the same range in 2006, under President George W. Bush. And in 2008 and 2011, for good measure.

The panel considered the science. Out in the wider world, politics took over.

Though the EPA can consider only public health when it sets the standard, not factors such as cost, the agency disregarded its advisory committee’s recommendation in 2008 and lowered the threshold from 80 ppb only down to 75. The EPA reconsidered the matter after Barack Obama was elected president. But following industry lobbying, he blocked the agency from setting a lower level in 2011.

Obama said he didn’t support a change at that time, given that the standard was due for reconsideration in 2013. And he emphasized “the importance of reducing regulatory burdens and regulatory uncertainty, particularly as our economy continues to recover.”

Then and now, business groups and key Republicans in Congress have contended that a lower standard would be too costly and difficult.

“EPA’s proposal … will lower our nation’s economic competitiveness and stifle job creation for decades,” U.S. Sen. James M. Inhofe said in a statement in November. Now chairman of the Senate Environment and Public Works Committee, he plans to hold hearings about the standard.

Air-quality officials in some states see a tighter standard differently — as a welcome relief.

Maryland is one example. Despite its ozone controls, the state had some of the highest concentrations in the East from 2011 to 2013, according to the most recent data from the EPA.

That’s because on almost all bad ozone days, the air already violates current standards as it crosses into Maryland, said Tad Aburn, director of the state’s Air and Radiation Management Administration. He wants to see upwind states reduce their smog, so he favors a stricter standard. “It’s really a regional problem,” he said.

An unexpected location

Air-quality field tech Mike Natchees traveled a wide-open stretch of road one drizzly January morning, past sagebrush, pump jacks and a gas flare burning like an oversized birthday candle. His goal: a shed-like structure atop an unpaved hill. Inside, devices measure how much ozone is in the air.

A tanker winds around a road on land overseen by the federal Bureau of Land Management. Oil and petroleum-waste trucks are a common sight in the Uinta Basin, but the agency says it’s taking many steps to reduce traffic and other oil-related emissions.

(Jamie Smith Hopkins/Center for Public Integrity)



That air is in Ouray, Utah, part of the Ute tribe’s 4.5-million-acre reservation. Cattle and wild horses probably outnumber the cars going by.

“Occasionally we see antelope out here,” said Preston McDonald, the tribe’s head of air-quality data analysis.

The reservation, along with wide swaths of federal land and small towns, makes up the Uinta Basin in northeast Utah. The mountain-encircled region sits far from urban areas. Population in the largest city, Vernal, barely tops 10,000.

Yet the region has an ozone problem. Not in the summer, but in the dead of winter.

Ozone has to be cooked into life by sunlight, which is usually too weak in the winter to produce much photochemistry. But reflection off snow gives the basin’s sunlight an extra kick. Snow cover also causes temperature inversions that keep polluted air from rising out of the basin.

In such conditions, volatile organic compounds from thousands of oil and gas sites across this region drive ozone way up. In 2013, an inversion-heavy year, the eight-hour average ozone level in Uintah County — spelled with an “h,” unlike the basin — exceeded the standard on 54 days. Concentrations spiked as high as 142 ppb, according to EPA figures. That’s “code purple,” the worst category for air pollution warnings.

Los Angeles County in California, by contrast, had 59 days that exceeded the standard that year, none of which were code purple.

The problem came to light in 2009 after a settlement between the EPA and an energy company operating on Ute land brought air monitors to the area, including the one in Ouray. The state kicked in money to study the problem. So did the Western Energy Alliance, federal agencies and other groups.

The studies determined that the oil and gas industry’s volatile organic compounds, or VOCs, are the big contributor. Annual emissions in the basin are on par with the VOCs spewed from 100 million vehicles driven thousands of miles each, according to a University of Colorado Boulder study.

“What might need to be done … and whether it would put the stranglehold on our oil and gas industry and shut it down, or whether just a little bit can make a big difference, are questions that are open still,” said Seth Lyman, a basin ozone researcher who heads Utah State University’s Bingham Entrepreneurship and Energy Research Center.

Seth Lyman, executive director of Utah State University’s Bingham Entrepreneurship and Energy Research Center, is a key ozone researcher in the Uinta Basin. He’s based in Vernal. (Jamie Smith Hopkins/ Center for Public Integrity)

The state of Utah requires stricter emission controls at new oil and gas sites than it did several years ago and passed regulations last fall to phase in retrofits of older, leaky equipment.

“VOC emissions should be reduced pretty dramatically … as things tighten up,” said Brock LeBaron, the state’s deputy director of air quality.

The environmental group WildEarth Guardians argues that those efforts aren’t sufficient, given the problem’s scale, and contends that all levels of government are falling down on the job in the basin. Many wells are on federal land.

The EPA has also declined to designate the area in violation of current ozone rules. (Its decision hinges on the fact that much of the past ozone data comes from monitors run by companies, not the government.) WildEarth Guardians sued over the matter in 2012 and awaits a ruling.

Several weeks ago, WildEarth’s Jeremy Nichols drove from Vernal to a wildlife refuge in Randlett, pointing out pump jacks and the tanker trucks that continually travel to and from the basin.

“It’s dangerous, the scale and pace of development,” said Nichols, the group’s climate and energy program director. “You’re seeing that with the air-quality issues. I mean, Vernal has a big-city ozone problem?”

It’s a place that in some ways looks as small-town as it is. A bubblegum-pink fiberglass brontosaurus grins at motorists above Vernal’s welcome sign, one of many local nods to the fossil-studded Dinosaur National Monument nearby.

But it’s also a town with 19 hotels and motels. Its glassy library and other high-end public buildings are different sorts of monuments than the pink dinosaur, ones that speak to years of oil-related taxes and royalties.

The owner of a juice and smoothie bar put up a miniature oil rig outside his business with a sign that seems to sum up the local sentiment: “I (heart) Drilling!”

A miniature rig beside the main drag in Vernal, in Utah’s Uinta Basin, stands as one business owner’s thumbs-up to drilling. (Jamie Smith Hopkins/Center for Public Integrity)

Oil and gas is the biggest employer in this county, according to state data. The industry directly accounts for about a fifth of the jobs here, and Uintah County Commission Chairman Michael McKee says it rises to half if you add in the ripple effect.

“You take any community, state or region with those dynamics, it’s important that we protect our jobs,” he said. “It’s also important that we have clean air and clean water and a good environment.”

Still, McKee sees a tighter ozone standard from the perspective of a job threat, one that looms as the region heads into an oil bust. Plunging prices prompted layoffs here and the fear of more.

McKee said officials are working on the ozone problem, but he doesn’t see how the basin could meet a tighter standard. While the area doesn’t get inversions every winter — McKee described the air as often “pristine” — compliance is judged based on a three-year average of each year’s fourth-highest daily reading. Inversion years go awfully high.

Utah State University studied asthma-related hospital visits and didn’t see an impact from the area’s high-ozone days, McKee added.

Lyman, whose center wrote that study, is quick to insert a cautionary note: Unlike Atlanta, central New Jersey and other urban areas where studies have found links, the basin has a tiny population. That makes it difficult, if not impossible, to jump the bar of statistical significance.

“We think there certainly is an impact, but exactly how it compares to summertime urban ozone is probably never going to be found out because there’s just not enough people here,” Lyman said.

Ozone, at least, is quiescent this winter. Warm temperatures have kept snow from piling up, warding off an inversion.

U.S. manmade volatile organic compound emissions

Source: Center for Public Integrity analysis of U.S. Environmental Protection Agency estimates.

U.S. manmade nitrogen oxides emissions

Source: Center for Public Integrity analysis of U.S. Environmental Protection Agency estimates.

But the VOCs are still here, millions of cars’ worth, ready to react when conditions are right. Stephanie Howard and Megan Crandall, both with the federal Bureau of Land Management in Utah, drove through the Pariette Wetlands area in the basin on a recent afternoon, explaining what the agency is doing to reduce emissions from ubiquitous oil and gas equipment. Steps include eliminating VOC-heavy evaporation ponds and pressing operators to replace leaky valves.

At the same time, the bureau is reviewing whether to allow more than 8,500 additional oil and gas wells in the region, double the number now under its jurisdiction. Leonard Herr, an air resources specialist for the Bureau of Land Management in Utah, knows that poses a tough question: Can total emissions be reined even as sources multiply?

He’s optimistic about that. And he doesn’t view a tighter ozone standard as a looming disaster for the basin.

“Nonattainment and failure to meet the standards after that isn’t the end of the world,” he said. “Just look at L.A. It’s been nonattainment almost my whole adult life, and it’s not a barren wasteland of economic development.”

The cost debate

When the EPA sets its ozone standard, the Supreme Court ruled in 2001, the Clean Air Act mandates that only one factor be weighed: what the best available science shows people can safely breathe.

Some members of Congress want to change that. Among the flurry of ozone bills submitted last year was the industry-supported “Clean Air, Strong Economies Act,” which would have required the agency to consider cost. It also would have barred a new standard from taking effect until 85 percent of counties failing the old standard fixed their air.

The companion bills, sponsored by U.S. Sen. John Thune, R-S.D., in the Senate and U.S. Rep. Pete Olson, R-Texas, in the House, didn’t get put to a vote last year. The bills were referred to committees that are now both headed by Republicans opposed to tighter ozone standards, which could give the measures new life if reintroduced as planned this year.

The National Association of Manufacturers’ Eisenberg characterized the effort as a way to give the EPA more flexibility, though he acknowledged that the group hasn’t spent much time considering how that might affect public health.

“We’re certainly hoping to have that discussion,” he said.

What’s more evident to manufacturers is the business impact when a community tips into ozone nonattainment. They must more than offset any pollution added if they want to expand or build something new, Eisenberg said. That could mean buying pricey credits on the emissions-offset market or shutting down another pollution source, he said, so more often manufacturers simply go elsewhere.

The EPA argues that the value of its proposal outweighs the expense because medical care and missed work days from ozone-triggered health problems add up fast. The agency estimated the benefit of a 65-ppb standard at $19 billion to $38 billion a year beginning in 2025, when it expects most of the country would meet that tighter threshold, compared with an estimated $15 billion in annual costs.

Trade groups say the negative impact would be far higher. A study for the National Association of Manufacturers suggests a 65-ppb standard would cost the U.S. economy $140 billion a year. The effects would include fewer jobs, higher electricity costs and restricted fossil-fuel production, the study says.

The Congressional Research Service weighed in last fall to declare the impact too far off to estimate. Ozone rules usually have deadlines that are years, even decades, into the future, and they often spur new, less expensive pollution technology.

“Aside from some statutorily mandated compliance measures, states — not EPA — decide what sources will be regulated and how stringent the controls will be,” the nonpartisan think tank added in its issue brief. “Often, industry can choose how to comply.”

Given that, the actual cost of past ozone reduction would be useful to know. But those numbers don’t seem to exist, despite all the effort spent trying to estimate them in advance the past 40 years.

The EPA, working with economists, did put a price tag on the expense of reducing all the pollutants covered by the Clean Air Act. Their $22-billion-a-year tally for 1973 to 1990 was less than half the annual amount the American Petroleum Institute projected in 1979 for the cost of reducing ozone alone.

Ozone timeline 1971 First ozone standard First ozone standard enacted in the U.S., a year after Congress passes the Clean Air Act and President Richard Nixon launches the U.S. Environmental Protection Agency.

1975 Auto makers take action Major auto manufacturers release cars with catalytic converters, a device that will substantially reduce pollution leading to ozone.

1970s New standards face pressure Pressure mounts on the EPA over its 80 parts-per-billion ozone standard, with both the Carter administration’s inflation-fighters and industry groups calling for it to be loosened.

1979 EPA yields, loosens standard The EPA raises its ozone threshold to 120 ppb.

1997 Back to 80 ppb The EPA tightens the ozone threshold back to 80 ppb over industry warnings that bans of barbecues and lawnmowers could follow.

2001 Supreme Court steps in The U.S. Supreme Court rules that, counter to industry groups’ wishes, the EPA must consider only what is safe to breathe when it sets its ozone standard, not cost.

2006 EPA considers tougher standards With research showing harms from lower amounts of ozone, the EPA’s independent scientific advisory panel on ozone unanimously recommends the standard be tightened to a level between 60 and 70 ppb.

2008 New standard prompts criticism EPA sets the ozone standard at 75 ppb, drawing a rebuke from its advisory panel that the level “fails to satisfy the explicit stipulations of the Clean Air Act that you ensure an adequate margin of safety for all individuals.”

2010 Obama’s EPA EPA, now under President Barack Obama, decides to revisit the ozone standard.

2011 Obama intervention As the EPA prepares to set a tighter standard, Obama intervenes, saying it should not be changed yet because it is due to be reconsidered in 2013 — after a presidential election year

2013 Health groups sue EPA With no ozone reconsideration underway, the American Lung Association and other groups sue the EPA.

2014 New standards by Oct. 2015 After a federal judge sets deadlines for action, the EPA proposes to tighten its standard by October 2015.

The ozone seesaw

In the history of environmental action, 1970 was a watershed year. President Richard Nixon created the EPA and — over the strenuous objections of automakers — signed the Clean Air Act into law.

“Through our years of past carelessness we incurred a debt to nature, and now that debt is being called,” Nixon, a Republican, said in his 1970 State of the Union address.

The Clean Air Act prompted the first national ozone standard, set at 80 ppb the next year. Catalytic converters followed, eventually reducing vehicle pollution in a big way.

But amid the high oil prices and inflation of the later ’70s, the Carter administration targeted regulations that advisors and industry argued were more cost than benefit. Carter’s inflation-fighting economists questioned whether the ozone studies of the time, then less definitive, really demonstrated that the pollutant needed to be reduced as much as the standard suggested. Up it went in 1979, to 120 ppb.

Industry groups had called for the standard to be set at 160 ppb or higher. Even 120 ppb, the American Petroleum Institute argued, would prompt “extensive social and economic disruption,” The Washington Post reported at the time.

The institute was then in the midst of an ozone lawsuit. The EPA, the trade group alleged, suppressed research showing the main source of smog was natural vegetation.

Patrick R. Zimmerman wrote those EPA-funded studies, and he says the agency did drag its feet in allowing him to publish his results. Later, he realized that officials were worried someone would purposely misinterpret his findings — which is what he says the institute did.

Trees and vegetation, Zimmerman found, emit certain VOCs at such high levels that they far out-produce man-made sources in forest-heavy regions. But that doesn’t mean urban smog is a tree problem, Zimmerman said — it’s not. (Rarely is ozone formed without an assist from man-made pollution, the EPA says.)

Zimmerman was appalled at what happened next.

“The American Petroleum Institute … wrote articles that they planted in all kinds of magazines and newspapers,” said Zimmerman, a scientist who now runs an environmental-technology firm in South Dakota. “It must have been 100 of them. Each article was pretty much the same, and it said something like, ‘Trees emit so much pollution, we can’t possibly control ozone, and the standards should be higher.’ ”

That apparently made an impression on Ronald Reagan. While running for president, he said trees and plants were bigger polluters than cars — his so-called “killer trees” moment.

The petroleum institute didn’t respond to the Center’s requests for comment.

Zimmerman couldn’t believe how little the actual science seemed to matter. He was glad to get out of ozone research.

“I really underestimated the importance of politics,” he said.

‘Dirty secret’

Outside Utah’s state Capitol building in January, several thousand people pressed together, some carrying signs, some wearing gas masks. They cheered speakers railing against air pollution. They clapped as a band turned the heavy-metal anthem “We’re Not Gonna Take It” into “We’re Not Gonna Breathe It.”

“People have just had enough,” said Daniel Roper, a Salt Lake City resident who attended the rally with his 21-month-old son. “It’s Salt Lake City’s dirty secret. We didn’t know about it when we moved here.”

Salt Lake City, like the Uinta Basin, is a region with air-quality challenges — ozone in the summer and harmful particulate matter in the winter. But unlike the Uinta, there’s a large contingent of residents here who loudly press officials to do more about it.

Nearly nine in 10 Utah residents view air pollution as a “serious problem,” driven by concerns in the Salt Lake area, according to a Colorado College poll released in February.

Rally speakers, elected officials among them, urged Utah’s legislature to accelerate efforts to clean the state’s air and criticized businesses that put themselves on the other side of the debate.

“Without public health, there is no prosperity,” said the Rev. David Nichols of Mount Tabor Lutheran Church in Salt Lake City, one of the speakers.

Cherise Udell, a rally organizer who founded the 3,000-member Utah Moms for Clean Air, hates the jobs-vs.-air argument with a passion. She has a different way of looking at clean-air standards: Who should pay for pollution?

Once, she says, everybody threw their waste into the streets. Then it became clear how unsanitary that was, and people had to shell out to get their trash hauled away.

She contends that some businesses are still dumping their garbage into the community by polluting the air — making other people pay for it in medical bills and worse health.

“That’s completely and utterly unfair,” Udell said. “If your neighbor was doing that, you’d be outraged.”

Maryam Jameel and Alexander Cohen of the Center for Public Integrity contributed to this article. A version of this story also appeared on National Geographic’s site.