In October, New York, New Jersey, and Connecticut filed a lawsuit accusing the Environmental Protection Agency of unlawfully allowing hundreds of coal power plants and other sources to pollute their air.
The disagreement centers on the so-called “good neighbor” provision of the Clean Air Act, which the EPA has used over recent decades to help eastern states improve their air quality by limiting emissions from sources in upwind states.
The air pollutant in question, ozone, can cause heart and lung disease when people breathe it in (in contrast to its sun-blocking benefits when it’s high above the Earth). The chain of events that begins with air pollution emissions at power plants and ends with ozone is complex, but well studied and well understood by scientists. As a general rule, higher summertime air pollution emissions from fossil-fuel sources lead to higher ozone downwind.
For precisely this reason, the EPA has been regulating cross-state air pollution for more than two decades.
New York City Inundated
New York state recently petitioned the EPA to control over 350 pollution sources they say inhibit the New York City metro area’s ability to comply with national air quality standards.
In denying the petition, President Donald Trump’s EPA determined that:
- New York City and its 12 million residents have nothing to worry about since they can’t definitively show that ozone will reach unhealthy levels in the future, and
- even if they did have something to worry about, they didn’t provide a “cost-effective” plan to reduce emissions from upwind states.
The EPA, relying on technicalities and a narrow interpretation of the Clean Air Act, is overlooking the bigger picture. New York’s scientists certainly have done their homework. Analysis accompanying the original petition showed that winds on the most polluted days brought pollution from nine upwind states. Not only that, but New York City has registered plenty of unhealthy days in recent years, so it’s safe to assume that—unless something changes—New Yorkers will have more to worry about in the future.
To show just how much air pollution drifts to eastern states from elsewhere, we used a model that effectively tracks air pollution transported by wind across the United States. Using our model, we ranked the impact of each of the nation’s 370 coal power plants on air quality in New York state, New Jersey, and Connecticut.
We found that power plants in Pennsylvania contributed 25% of all coal-related air pollution in these states. Power plants in five more states—West Virginia, Ohio, Indiana, Michigan, and Kentucky—cause even more pollution than plants located in New York, New Jersey, or Connecticut contributed to their own states.
In 2016, home-grown pollution from local sources accounted for just 3% of all ozone-forming pollution from power plants in New York, New Jersey, and Connecticut.
Certainly, this story does not completely absolve eastern states. Factories in those states spew plenty of emissions that make it into the air. Gasoline and diesel cars and trucks emit harmful pollutants even closer to human nose-level, and airplanes and ships emit pollution from the urban fringes.
While remembering that everyone is upwind of someone, these states should continue mandating that those sources use cleaner fuels and scrub their exhaust before it’s emitted.
But we are headed in the opposite direction. To the surprise of many, emissions from some of the largest coal power plants—including some that have the biggest impacts on New York air quality—actually increased in 2018, a possible consequence of deregulation by the EPA and other agencies that have kept the cost of burning coal competitive with cleaner energy sources.
As a result, recent measurements have shown that atmospheric concentrations of microscopic particles called PM2.5 have risen across the United States since 2016. These findings have raised alarm among environmentalists and public health professionals that the current EPA is turning a blind eye to enforcing its own air quality regulations. President Trump’s recent moves to limit the science available to inform EPA decisions reinforces these fears.
Armed with decades of evidence and newer model results, eastern states are correct to argue that the agency is not upholding its mandate to protect human and environmental health. And everyone breathing air on the East Coast suffers the consequences every day.
This column does not necessarily reflect the opinion of The Bureau of National Affairs, Inc. or its owners.
Lucas Henneman is a postdoctoral fellow at the Harvard T.H. Chan School of Public Health. He studies the air pollution and public health implications of environmental regulations.
Corwin Zigler is an associate professor of statistics and data sciences at the University of Texas at Austin and Dell Medical School. His research focuses on statistical and epidemiological analysis of observational studies, with emphasis on air pollution regulatory policy.
The authors’ work was supported by grants from the National Institutes of Health (R01ES026217) and the Environmental Protection Agency (EPA 83587201). The contents of this work are solely the responsibility of the grantees and do not necessarily represent the official views of the EPA. Further, the EPA does not endorse the purchase of any commercial products or services mentioned in the publication.