Environmental Groups Give Notice of Intent to Sue for Toxic Discharges from Ottumwa Coal Ash Landfill

DES MOINES—Today three environmental groups notified Alliant Energy’s Iowa affiliate of their intent to sue for unpermitted discharges of polluted groundwater that is pumped out from under an Ottumwa coal ash landfill. The notice letter, which is required before filing suit under the Clean Water Act, allows 60 days for the discharger to come into compliance or for the state to begin enforcement action. The Iowa Environmental Council (IEC), Sierra Club, and Environmental Law & Policy Center (ELPC) worked together on the notice.

Alliant’s Iowa affiliate, Interstate Power and Light (IPL), has discharged polluted groundwater from the site for decades. The discharge was covered under a state-issued stormwater permit, but the Iowa Department of Natural Resources informed IPL in 2023 that the discharge did not qualify under the permit due to the presence of arsenic and other toxic pollutants. IPL has not stopped the discharge or applied for a new permit to allow the discharge.

“The Clean Water Act prohibits discharges without a permit, full stop,” says Michael Schmidt, General Counsel at the Iowa Environmental Council. “Continuing to discharge these pollutants — including arsenic, molybdenum, and other metals — violates the Clean Water Act.”

IPL has operated the coal ash landfill since 1995 and had to lower the groundwater table to ensure the liner below the coal ash worked properly. While IPL has tested the groundwater for pollution under a solid waste permit, it never reported the pollutants under the stormwater permit. 

The polluted groundwater is discharged to a wetland that flows to a creek, then into the Des Moines River upstream of the City of Ottumwa drinking water intake. Sierra Club and IEC highlighted the risks from coal ash waste, including Ottumwa, in Iowa earlier this year. 

“For decades, utilities like MidAmerican and Alliant have disposed of leftover coal ash waste by dumping it in ponds and landfills where it can leak into groundwater, creating a toxic soup of heavy metals and carcinogens like arsenic, lead, and mercury, which have been linked to cancer, heart and thyroid disease, reproductive failure, and neurological harm,” said Josh Smith, Senior Attorney with Sierra Club. “It is critical that we keep this toxic waste out of the Des Moines River.”

In 2024, IPL proposed to discharge untreated leachate, which is water that has filtered through the coal ash and picked up pollutants. After IEC objected to the proposal, IPL agreed not to discharge the contaminated water. The landfill has continued to produce leachate, which is being taken to the city wastewater treatment plant.

“This case shows exactly why Iowa must move away from coal and toward clean energy,” says Josh Mandelbaum, Senior Attorney at ELPC. “As long as our utilities continue relying on dirty and uneconomic coal, Iowans will pay the price with toxic pollution in our air and drinking water.”  

MidAmerican Energy, which is the majority owner of the Ottumwa coal plant, assumed that the plant would operate through 2041 in its resource plan. Continued operation of the coal plant will expand the coal ash landfill.

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The Iowa Environmental Council is the state's largest and most comprehensive environmental alliance, comprised of diverse organizations and individuals working together to protect Iowa's natural environment. Through education, advocacy, and coalition-building, the Council raises awareness, generates action, and creates large-scale change. We work on federal, state, and local public policy issues to ensure a just, healthy environment and sustainable future for all Iowans.

The Sierra Club is America’s largest and most influential grassroots environmental organization, with more than 3.5 million members and supporters. In addition to protecting every person's right to get outdoors and access the healing power of nature, the Sierra Club works to promote clean energy, safeguard the health of our communities, protect wildlife, and preserve our remaining wild places through grassroots activism, public education, lobbying, and legal action.

The Environmental Law & Policy Center (ELPC) is the Midwest's leading public interest environmental legal advocacy organization. We develop strategic campaigns to protect natural resources and improve environmental quality. Our multi-disciplinary staff employs teamwork approaches using legal, economic, and public policy tools to produce successes that improve our environment and economy.