(Radio Iowa) – An Iowa environmental group says state regulators should reject a proposal from MidAmerican Energy to release coal ash wastewater from a power plant near Sioux City. The proposal affects the George Neal Energy Center where water that leaches through coal ash waste is collected in storage ponds. When the ponds are full, some wastewater would be released into the Missouri River. Steve Guyer, with the Iowa Environmental Council, says the utility should follow the new, stricter guidelines for wastewater containing hazardous pollutants.

“Has this previously been released to the river? Yes,” Guyer says, “but the difference is now the EPA has called out additional standards that need to be applied.” Guyer says that wastewater carries chemicals and heavy metals such as arsenic and mercury.

“Many of these are what are known as bio-accumulators, notably mercury, for instance, is a bio-accumulator,” he says. “It accumulates in the fish tissue.” In a statement, the utility says it follows all state and federal guidelines, and the proposal would only come into play in years with extremely heavy rain. The Iowa D-N-R must approve the plan.

(reporting by Grant Gerlock, Iowa Public Radio)