The Environmental Protection Agency (EPA) plans to reconsider the Obama-era Mercury and Air Toxics Standards (MATS), a rule that restricts some of the most toxic air emissions from power plants.

The EPA, under the leadership of Acting Administrator Andrew Wheeler, a former coal industry lobbyist, has issued a draft proposal that questions whether it was “appropriate and necessary” for the agency to set standards in 2012 for mercury and other toxic air pollution emitted by power plants.

Environmental groups and lawmakers are concerned that the Trump administration is seeking to weaken one of the most important and effective clean air rules for power plants. Prior to the rule, fossil-fueled power plants were the largest source of mercury in the country.

“The only people who want to turn back the clock on this life-saving policy are the coal executives who employed Andrew Wheeler and gave big to Donald Trump’s campaigns,” Mary Anne Hitt, senior director of Sierra Club’s Beyond Coal campaign, said Wednesday in a statement.


The MATS rule created the first-ever federal standards to limit mercury, acid gases, and other air toxic pollution from power plants. Since its implementation, the MATS rule, combined with other regulations, has achieved a 90-percent reduction in mercury power plant emissions and prevented thousands of premature deaths.

Section 112 of the Clean Air Act authorizes the EPA to regulate hazardous air pollutant emissions from power plants if the agency finds that such regulation is “appropriate and necessary.”

EPA spokesperson Molly Block said in an email to ThinkProgress that the agency has issued a draft proposal on the rule that will soon be sent to the White House’s Office of Management and Budget, beginning a review process on the plan. That process typically takes between 60 and 90 days. At the conclusion of that process, the EPA will release the proposed rule for public comment.

“One of a number of issues the EPA is assessing in the context of the appropriate and necessary analysis is whether and how to account for co-benefits,” Block said of the benefits that come as a result of reduced emissions such as lower healthcare costs.


“EPA knows these issues are of importance to the regulated community and the public at large,” she said, “and is committed to a thoughtful and transparent regulatory process in addressing them.”

The review of the rule is occurring even though most power plant owners have invested huge amounts of money in complying with the regulation, which required the installation of pollution control technology.

The Trump administration’s attempt to rollback MATS “is perhaps the most egregious example yet of the Trump administration siding with a handful of millionaire fossil fuel executives and industry insiders over the working families and communities they pollute every day,” Hitt said.

"Trying to rollback MATS is perhaps the most egregious example yet of the Trump administration siding with a handful of millionaire fossil fuel executives and industry insiders over the working families and communities they pollute every day.” More: https://t.co/CRDmDRa9jZ — Mary Anne Hitt (@maryannehitt) August 29, 2018

The EPA, under President Barack Obama, found the regulation was warranted, even if the costs of complying with the rule were high. Industry groups countered that the Obama EPA, in its analysis of the costs and public health benefits of the rule, relied on “co-benefits,” which cover the reduction in pollutants aside from those directly regulated by the standards.


In 2015, the Supreme Court ruled that the EPA had not adequately considered the cost of the regulation. That ruling sent the standard down to the D.C. Circuit Court of Appeals. Later that year, the EPA issued a supplemental finding, concluding that it is still “appropriate and necessary” to regulate hazardous air pollutants from coal- and oil-fired electric generating units. The Obama EPA found the costs were justified because the rule saved consumers on healthcare bills.

The EPA estimated that MATS protections prevent up to 11,000 premature deaths and more than 100,000 asthma and heart attacks each year. The value of those benefits to the public is estimated to be as high as $90 billion annually.

The adoption of the rule was an important milestone in regulating power plant emissions because mercury is a potent neurotoxin of significant ecological and public health concern, especially for children and pregnant women.

The EPA’s plans to reconsider its current restrictions on power plant emissions of air toxics and mercury “is particularly egregious, even by Trump standards,” Sen. Tom Carper (D-DE), said Wednesday in a statement.

“As I made very clear to EPA just last week, the Mercury and Air Toxics Standards (MATS) Rule is currently surpassing expectations, and changing it now not only doesn’t make sense, but is irresponsible,” Carper said.

Last week, Carper and Sen. Lamar Alexander (R-TN) sent a letter to Acting Administrator Wheeler, stating that MATS is overachieving expectations. “We are seeing public health benefits faster than predicted,” the two senators wrote.

The senators also cited a July 10 letter sent to the EPA by electric industry trade groups that represent coal plant-owning companies. In the letter, the trade groups highlighted the positive impact the rule has had on reducing toxic emissions.

Since the rule took effect in 2012, owners and operators of coal- and oil-fired power plants have spent more than $18 billion to comply with the MATS rule. These investments, state requirements, other Clean Air Act programs, and other drivers have reduced mercury emissions by nearly 90 percent over the past decade, the industry trade groups wrote in their letter.

Given this level of investment and the emissions reductions, regulatory and business certainty under the Clean Air Act is “critical,” the industry trade groups said.

“I warned this administration not to touch this rule that has the support of environmental groups, health organizations, states, industry and a bipartisan coalition of lawmakers,” Carper said. “It’s why I fought like hell to protect the rule when EPA issued it in 2012, and it’s why I’ll keep fighting the agency’s foolish decision to abandon it.”