Wastewater, rather than air pollution, may be the wedge that finally pushes coal out of its place as the U.S.’s power source.

Coal-burning plants in the United States had an October deadline to get better at filtering their wastewater. A new wastewater rule, enacted in the early days of the Biden administration, reversed Trump-era rollbacks weakening environmental protections and then went further. Under the new regulations, power plants have to ensure coal ash, mercury, arsenic, selenium, and more toxic heavy metals are all entirely removed from plant wastewater before it can be released. The rule affects 75 coal-burning power plants nationwide.

The October deadline was a soft one – plants not already in compliance only had to submit a plan to their state regulators explaining how they planned to reach compliance by 2028. Despite this, 26, over a third of the affected plants have responded by saying that they will stop burning coal. 21 of those plants intend to shut down, only 5 planning to convert to cleaner-burning natural gas.

“The free ride these plants have been getting is ending in a lot of ways,” said Zack Fabish, a Sierra Club lawyer. The Sierra Club tracks state regulatory filings to increase transparency for the public. “And them choosing to retire by 2028 probably reflects the reality that a lot of the subsidies they have been getting in terms of being able to dump their wastewater into the commons, they are not going to be able to do that in the future.”

According to EPA estimates, the rule will reduce the discharge pollutants into our waterways by nearly 200 thousand U.S. tons a year, with a cost of around $200 million collectively to all currently active plants.

For those concerned about the jobs to be lost, the two largest plants intending to close, Keystone and Conemaugh in Pennsylvania, together employ fewer than 500 people.

Photo: Shutterstock