Megan Butler

(CN) — The Environmental Protection Agency on Wednesday proposed new wastewater treatment standards for coal-fired power plants to reduce discharges of toxic metals and other pollutants into nearby waterways.

These steam electric plants use coal to heat water in boilers and generate steam, which is used to drive turbines connected to electric generators. The plants generate wastewater discharge containing selenium, mercury, arsenic, nickel, halogen compounds such as bromide and chloride, and other toxic pollutants, which can contaminate drinking water sources and recreational waters and harm aquatic life.

The toxins can stick around for years and pose health risks such as cancer and even lowered IQs in children. They're also known to cause deformities and reproductive harm in fish and other wildlife. Some minority and low-income communities have greater exposure to, and are therefor, at greater risk from, the pollutants due to their close proximity to the power plants.

To achieve that goal, the proposal revises the so-called ELGs, short for effluent limitations guidelines, for three types of wastewater generated at coal-fired power plants: flue gas desulfurization wastewater, bottom ash transport water and combustion residual leachate.

These standards were last revised in 2020. Since then, advancements have paved the way for new applications of membrane filtration on flue gas desulfurization wastewater, dry handling or closed-loop systems on bottom ash transport water, and chemical precipitation on treating wastewater from combustion residual leachate to remove pollutants.

The EPA estimates the proposed regulation would reduce the discharge of these pollutants by approximately 584 million pounds per year.

The proposed new treatment standards for leachate from coal ash disposal sites were required as a result of a court victory won by Earthjustice and partner groups in 2019, when the Fifth Circuit struck down the EPA's attempt to exempt these wastewater sources from more stringent discharge limits.

But Earthjustice says that the EPA should have also proposed national standards for wastewater from coal ash impoundments, which can contain pollutants that cause cancer, heart disease, reproductive failure and stroke.

“This rule will finally force the power industry to do what it should have done decades ago, requiring coal-burning plants to either use cost-effective wastewater treatment technologies that are already used by many other industries, or stop burning coal altogether,” said Thom Cmar, senior attorney with Earthjustice.

He added, “We urge EPA to finalize the strongest rule possible as quickly as possible, so that power companies will no longer be allowed to profit off of treating our waterways like an open sewer for toxic pollutants that threaten human health and degrade our environment. Power plants have already had many years to comply with these standards, and should not be allowed to wait until the end of this decade.”

Utility owners of dozens of coal-fired power plants have announced their plants will close down by 2028. According to the EPA, these types of plants "are increasingly aging and uncompetitive sources of electric power" in many parts of the country and face many regulations to control pollution.

However, under the proposal, separate requirements would be introduced for a new category of facilities that have complied with the EPA's former rule requirements and have until 2032 to cease operations. These facilities would not be subject to the new, more stringent "zero-discharge" requirements and would retain the 2020 rules for wastewater.

While the Clean Water Act prohibits the discharge of pollutants from a point source into U.S. waters, it allows the EPA to establish national regulations to restrict pollution from discharges that are authorized through a National Pollutant Discharge Elimination System (NPDES) permit.

The EPA said the new proposal was motivated in part by recent actions from the Biden administration aimed at reaching net-zero greenhouse gas emissions by 2050.

Steam electric power plants are one of the country's largest contributors of greenhouse gas emissions, according to the EPA. It is estimated that about 25% of greenhouse gas emissions in 2020 came from electricity generation overall.

President Joe Biden's Inflation Reduction Act that was signed into law last August includes numerous provisions affecting the steam electric power generating industry and includes incentives to transition into alternate forms of energy production such as wind and solar.

Two online hearings about the proposal seeking public comments will be held on April 20 and 25.

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