As environmentalists voiced concerns in Washington about possible changes to the Environmental Protection Agency's rules on disposing coal ash waste, some in Missouri chose to express their opposition by staging a protest at a major utility corporation's doorstep.

The Missouri chapter of the Sierra Club gathered a small band of supporters Tuesday at Ameren Missouri's headquarters in St. Louis. They held large signs that showed images of Ameren's four power plants in Missouri and listed details about the toxic heavy metals that coal ash contains, such as arsenic.

Ameren Missouri announced recently that it plans to close all of its coal ash ponds by 2022. However, activists want the regulators to address the contamination the ponds have already caused and are unhappy that Ameren has chosen to close its ponds by leaving them in place.

The proposed amendments to the EPA's 2015 coal ash rule would give more power to states to regulate coal ash regulations and could eliminate a requirement to publish groundwater monitoring data online. Missouri state legislators are considering a bill that environmentalists fear will weaken oversight of the ponds and landfills that utility companies use to dump coal ash waste.

"We want to see stronger protections in place, we want to see these sites cleaned up," said Sara Edgar, a campaign representative at the Missouri Sierra Club. "There are ongoing efforts at all levels to do less and less to protect our communities from coal ash."

The protesters included residents who live near Ameren's power plants. Tom Diehl, who lives four miles from the Meramec Energy Center, said he's worried that flooding from the Mississippi River has spread toxic materials from the plant's coal ash ponds into a nearby subdivision.

"The water does get into the immediate neighborhood and you know, there are hundreds of kids who live close to that plant," Diehl said.

Ameren Missouri released the results of its groundwater and surface water testing around its coal ash ponds in late February. The company sent crews out to test the water quality surrounding the ponds, said Craig Giesmann, the utility's manager of water quality.

"They found zero evidence of any contaminants from our ash ponds in those surface water bodies," Giesmann said.

Missouri has 37 coal ash ponds, according to the Missouri Department of Natural Resources. Many of them are unlined.

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