Two Ameren coal plants in the St. Louis region are receiving an air pollution exemption from President Donald Trump's administration.
The Labadie Energy Center in Labadie and the Sioux Energy Center in West Alton are both on an official list of plants receiving federal Clean Air Act exemptions.
Trump signed a presidential proclamation last week that gave certain power plants two extra years to comply with a rule that restricts emissions of mercury and other hazardous air pollutants from coal-fired power plants.
In the proclamation, Trump said President Joe Biden's administration tightened the standards to a level that was not commercially viable for power companies.
"The Rule places severe burdens on coal-fired power plants and, through its indirect effects, on the viability of our Nation's coal sector," the proclamation said.
The Labadie Energy Center is the fifth-largest emitter of mercury in the country, according to the Environmental Protection Agency. In 2023, the plant emitted more than about 250 other coal plants around the county. Ameren said its mercury emissions at Labadie have decreased by 92% since 2005.
In 2024, the Biden administration published a final rule that updated the emissions standards, reducing the mercury limit by 70%.
"Controlling these emissions from power plants improves public health for all Americans by reducing the risk of fatal heart attacks, cancer, developmental delays in children, and also reduces adverse environmental impacts," a Biden-era EPA press release said.
In 2024, the Supreme Court refused to intervene in a case challenging the new rule.
To receive the exemption, the Trump administration asked power plant operators to email the EPA. In Ameren's request, sent on March 31, Ameren Missouri's director of environmental services, Craig Giesmann, said achieving compliance with the rule would risk national security and the reliability of St. Louis' grid while increasing energy costs for customers.
"We are committed to selecting cost-effective solutions that minimize the impact on customer rates," Giesmann said in a statement to St. Louis Public Radio. "This brief exemption will allow us to explore all viable options."
Environmental organizations say this will put St. Louisans at risk. Mercury is one of the most well-documented toxins in history, said Andy Knott, the Sierra Club's Beyond Coal deputy director.
"Ameren is literally putting profit above people by seeking this exemption and delaying really critical safeguards for public health," Knott said.
Power plants were supposed to be in line with the rule by 2027. The Trump exemption gives the listed power plants an extra two years, starting compliance in 2029.
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