EPA Proposes Tightening Hazardous Air Pollutant Emissions from Coal-fired Power Plants

April 6, 2023

A new federal rule proposal seeks to tighten the emission of several toxic pollutants from power plants fueled by coal and oil, a move that would affect a large portion of electricity production in Indiana.

The U.S. Environmental Protection Agency proposed an update to the 2012 Mercury and Air Toxics Standards that would require the power plants to reduce emissions of mercury, acid gases and other pollutants and install new monitoring and control technologies.

The proposed rule would reduce mercury emissions from coal-fired power plants by 70% and filterable particulate matter by 67%.

Mercury is a neurotoxin that can cause kidney damage, respiratory failure and death in high doses. Inhaling mercury can also harm the brains and nervous systems of unborn infants, resulting in reduced cognition, memory, attention span and other adverse effects.

It can be breathed in when emitted by power plants or can enter the body through contact with contaminated environments. Mercury can make its way through soil into water, contaminating miles of waterways and poisoning aquatic life. A 2015 study found elevated levels of mercury downstream from the AES Indiana Harding Street Generating Station, which was then the state’s largest emitter of mercury.

Filterable particulate matter includes sulfur dioxide, nitrogen oxides and carbon dioxides and other pollutants that can be physically captured on a filter during sampling.

Sulfur dioxides and nitrogen oxides can harm the respiratory system and make breathing difficult.

The EPA projects the proposed rule will provide up to $3 billion in net public health benefits over nine years but will cost power plant owners at least $230 million.

“America is leading the way in innovation, and our work to protect public health is no different. By leveraging proven, emissions-reduction measures available at reasonable costs and encouraging new, advanced control technologies, we can reduce hazardous pollution from coal-fired power plants, protecting our planet and improving public health for all,” said EPA Administrator Michael S. Regan.

The proposed rule could result in healthier air for Hoosiers, as the largest source of mercury emissions are coal-fired power plants.

Indiana ranks third in the nation for total coal consumption and coal consumption for electricity generation, according to the U.S. Energy Information Administration.

As of December 2022, 55.5% of the electricity produced in the state is made using coal.

Coal use peaked in the mid-2000s and has been on a mostly downward trajectory since then, mostly due to higher prices for coal and higher operating and maintenance costs.

Some electric utilities, like the Northern Indiana Public Service Co. and AES Indiana, have announced they are planning to retire all their coal-fired power plants later this decade. Other utilities, like Duke Energy Indiana, plan to hold on to their coal plants until well into the next decade.

Moving away from coal-fired electric generation has resulted in cleaner air for Hoosiers. In 2002, mercury emissions were 10,565 pounds per year. By 2012, mercury emissions from coal-fired power plants were reduced to 2,174 pounds per year.

According to the Indiana Department of Workforce Development, the entire state mining industry supports about 2,500 jobs, only a small portion of the state’s total workforce.

But the coal industry has an outsized lobbying reach, with both local and out-of-state coal interests pouring money into the state to convince lawmakers to keep the state from transitioning away from coal.

Gov. Eric Holcomb recently signed into law a piece of legislation that makes it harder to retire coal-fired power plants. Senate Enrolled Act 9 requires utilities to receive the permission of the Indiana Utility Regulatory Commission before deciding to retire power plants ahead of schedule. If the IURC denies permission, the utility cannot submit another request to close the plants for another 180 days.

The bill’s main author, Sen. Jean Leising, said the bill was intended to maintain the reliability of the electric grid serving Indiana until renewable energy becomes more dependable.

Groups like the National Mining Association said the rule and other EPA proposals will make it impossible for utilities to make decisions based on the needs of their customers.

“Intermittent renewable power additions will require a massive expansion of transmission infrastructure and energy storage — an effort that will take years to complete — in order to fill the gulf left by coal plant retirements. In fact, in 2022, as many as 40 planned coal plant retirements were postponed or scrapped largely due to acute grid reliability challenges where utilities and grid operators have made it clear closing plants would be reckless,” the National Mining Association said in a press release.

“The U.S. coal fleet continues to play an outsized role in providing dispatchable fuel diversity, fuel security and ramping up power supply during periods of surging demand when other sources of power cannot. EPA’s willful disregard of the repercussions of its decisions on Americans and on our energy future is plainly irresponsible.”

A recent investigation into the failures of the PJM Interconnection, the regional electric grid serving parts of eastern Indiana and 12 other states, during a major 2022 winter storm showed coal was the second-least reliable energy source during the storm.
The EPA’s rule proposal was applauded by environmental groups like the Sierra Club and Earthjustice.

“It's alarming to think that toxic pollutants from coal plants can build up in places like Lake Michigan where we go camping and swimming in the summer, and where people fish to feed their families,” said Holly Bender, Sierra Club senior director of energy campaigns. “Today, we applaud the Biden Administration's commitment to prioritizing children's health, and we urge the EPA to quickly and decisively implement strong mercury and air toxics standards. Our kids deserve to live and play in a healthy, safe environment, and our leaders must do everything in their power to make that a reality."

The EPA will begin accepting public comments about the proposed rule later this month.

EPA Proposes Tightening Hazardous Air Pollutant Emissions from Coal-fired Power Plants