Environmental groups to sue Alliant claiming groundwater pollution

Environmental groups seek to sue an an Iowa coal plant operator under the Clean Water Act, claiming it is discharging water contaminated by coal ash without a permit. (Stock photo by Monty Rakusen via Getty Images)

Several environmental groups intend to sue Alliant Energy’s Iowa affiliate, claiming it is discharging polluted groundwater into waters upstream of Ottumwa without a permit. 

The Iowa Environmental Council, Sierra Club, and Environmental Law & Policy Center issued a letter of intent to sue, as mandated under the Clean Water Act, which gives the company 60 days to come into compliance. 

The threatened lawsuit deals with the Ottumwa Midland Landfill, a coal ash landfill that has been used by Interstate Power and Light Company, a subsidiary of Alliant Energy, since 1995. 

The landfill has a liner that separates coal ash, or waste material from burning coal, from the groundwater. Piping below the landfill removes the groundwater from underneath the lining and discharges it, at a rate of up to 84,000 gallons per day, to a wetland that flows into a tributary of the Des Moines River, according to the letter. 

This groundwater is not supposed to come into contact with any of the contaminants in the landfill above it, but the environmental groups pointed to IPL monitoring data that shows the discharge contains arsenic, barium, boron, calcium, cobalt, iron, lithium, magnesium, manganese, molybdenum, zinc, and “other pollutants below reporting limits.” 

“Thus, the underdrain water is contaminated and is not an allowed discharge under Stormwater General Permit 1,” the letter said. 

These are some of the same contaminants noted in a study released by IEC and the Sierra Club in February that found coal ash landfills and ponds caused heightened levels of toxic heavy metals and pollutants in nearby groundwater. 

The study pulled from self-reported data at MidAmerican Energy Company plants, including the Ottumwa Generating Station which is owned by both MidAmerican and IPL. MidAmerican, however, disputed the findings of the study. 

The “underdrain” discharge from the Ottumwa landfill was covered by a stormwater discharge permit with the Iowa Department of Natural Resources, but in 2023, DNR informed the company that the discharge did not meet the definition of “uncontaminated groundwater” covered by the permit. 

The letter said IPL did not apply for an additional permit for this discharge and therefore “has been discharging, and continues to discharge, pollutants into waters of the United States without permit authorization.” 

Melissa McCarville, a spokesperson for Alliant Energy said the company has been “actively communicating” with DNR and is “systematically working” toward a solution for the groundwater discharge. 

“Alliant Energy is dedicated to serving our customers and communities throughout the state,” McCarville said in a statement. “Driven by our mission and core values, we are steadfast in our commitment to environmental compliance including abiding by all regulated and required groundwater monitoring processes.” 

Michael Schmidt, an attorney for Iowa Environmental Council, said it has been “more than a year and half” since DNR informed the company of the permitting issue. 

“It’s that ongoing delay that we are concerned about,” Schmidt said. “We have these discharges of arsenic and other metals going into the water on a continuous basis without really any oversight from DNR, because there is no permit coverage.” 

McCarville said there is “no reason to believe” the discharge interacted with the contents of the landfill. 

“As designed and originally permitted, the system does not come into contact with the landfill’s content,” McCarville said. 

In late 2024, the company announced a plan to reroute the discharge to the Des Moines River, to which IEC objected. 

McCarville said depending on reviews and approvals, construction on a new design for the discharge could begin this spring. 

The U.S. Environmental Protection Agency Administrator Lee Zeldin announced a slew of plans Wednesday to roll back certain regulations on energy production and to change the definition of Waters of the United States, which are waters protected under the Clean Water Act. 

Schmidt said this would not affect the intent to sue because the discharge is occurring in waters that are “clearly” waters of the United States. 

“The notice letter is about a foundational element of the Clean Water Act, requiring a permit for any discharge of pollutants,” Schmidt said. 

“It’s another example of why the process that we have of burning coal to put pollutants into the air, and create the solid waste and have these water discharges, is a continuing problem. The more we do it, the more problems like this we create.”