Regulations are expected to impact 75 coal-fired power plants //

Climate change isn’t what’s driving some U.S. coal-fired power plants to shut down. It's the expense of stricter pollution controls on their wastewater.

Dozens of plants nationwide plan to stop burning coal this decade to comply with more stringent federal wastewater guidelines, according to state regulatory filings, as the industry continues moving away from the planet-warming fossil fuel to make electricity.

The new wastewater rule requires power plants to clean coal ash and toxic heavy metals such as mercury, arsenic and selenium from plant wastewater before it is dumped into streams and rivers. The rule is expected to affect 75 coal-fired power plants nationwide, according to the Environmental Protection Agency. //

Those plants had an October deadline to tell their state regulators how they planned to comply, with options that included upgrading their pollution-control equipment or retiring their coal-fired generating units by 2028.

The national impact of the wastewater rule is still coming into focus, but at least 26 plants in 14 states said they will stop burning coal, according to the Sierra Club, which has been tracking state regulatory filings. Twenty-one of the plants intend to shut down, and five indicated they may switch to natural gas, the environmental group said.