Several environmental groups plan to sue Alliant Energy’s Iowa affiliate, alleging unlawful discharge of polluted groundwater from the Ottumwa Midland Landfill into local waters without a permit. The Iowa Environmental Council, Sierra Club, and Environmental Law & Policy Center issued a letter of intent under the Clean Water Act, prompting a 60-day compliance period. Contaminants such as arsenic and barium in the groundwater, which should not contact landfill waste, were reported. Alliant Energy asserts it is working with the Iowa Department of Natural Resources to resolve the issue. The environmental groups express concern over ongoing pollution without proper oversight.
OTTUMWA, Iowa (IOWA CAPITAL DISPATCH) – Multiple environmental organizations are preparing to take legal action against Alliant Energy’s Iowa subsidiary, alleging that it is releasing contaminated groundwater into streams located upstream of Ottumwa without the proper permits.
The Iowa Environmental Council, Sierra Club, and Environmental Law & Policy Center have sent a letter of intent to sue as required by the Clean Water Act, which allows the company 60 days to achieve compliance.
This potential lawsuit pertains to the Ottumwa Midland Landfill, a coal ash landfill that has been operated by Interstate Power and Light Company, a part of Alliant Energy, since 1995.
The landfill features a liner designed to keep coal ash, which is the waste produced from burning coal, separate from the groundwater. Piping installed beneath the landfill extracts groundwater from underneath this liner and releases it at a rate of up to 84,000 gallons per day into a wetland, which subsequently feeds into a tributary of the Des Moines River, as outlined in the letter.
This groundwater should not mix with any contaminants present in the landfill above, yet the environmental groups cited monitoring data from IPL that indicates the discharged water contains arsenic, barium, boron, calcium, cobalt, iron, lithium, magnesium, manganese, molybdenum, zinc, and “other pollutants below reporting limits.”
“As a result, the underdrain water is contaminated and does not qualify as an allowable discharge under Stormwater General Permit 1,” stated the letter.
These contaminants were among those identified in a study released by IEC and the Sierra Club in February, which revealed increased levels of toxic heavy metals and pollutants in nearby groundwater due to coal ash landfills and ponds.
The study utilized self-reported data from MidAmerican Energy Company facilities, including the Ottumwa Generating Station, which is jointly owned by MidAmerican and IPL. However, MidAmerican has contested the study’s findings.
The “underdrain” discharge from the Ottumwa landfill was previously authorized under a stormwater discharge permit obtained from the Iowa Department of Natural Resources, but in 2023 the DNR informed the company that this discharge no longer met the definition of “uncontaminated groundwater” referenced in the permit.
The letter emphasized that IPL has not applied for a new permit for this discharge, and consequently “has been discharging, and continues to discharge, pollutants into waters of the United States without permit authorization.”
Melissa McCarville, a spokesperson for Alliant Energy, stated that the company has been “actively communicating” with the DNR and is “systematically working” to resolve the groundwater discharge issues.
“Alliant Energy is committed to serving our customers and communities throughout the state,” McCarville said in a statement. “Guided by our mission and core values, we are resolute in our commitment to environmental compliance and adhere to all regulated groundwater monitoring processes.”
Michael Schmidt, an attorney for the Iowa Environmental Council, revealed that it has been “over a year and a half” since the DNR alerted the company about the permitting problem.
“Our concern lies with this ongoing delay,” Schmidt remarked. “These arsenic discharges and other metals are continually being released into the water without sufficient oversight from the DNR, since there is currently no permit coverage.”
McCarville stated there is “no reason to believe” that the discharge has interacted with the landfill contents.
“As designed and initially permitted, the system does not contact the landfill’s contents,” McCarville maintained.
In late 2024, the company revealed plans to redirect the discharge to the Des Moines River, a move that IEC opposed.
McCarville indicated that construction on a revised discharge plan could commence this spring, pending reviews and approvals.
U.S. Environmental Protection Agency Administrator Lee Zeldin announced various plans on Wednesday to roll back specific regulations pertaining to energy production and modify the definition of “Waters of the United States,” which are protected under the Clean Water Act.
Schmidt noted that this would not impact the intent to sue, as the discharge is taking place in waters that are “clearly” categorized as Waters of the United States.
“The notice letter addresses a fundamental aspect of the Clean Water Act, which requires permits for any discharge of pollutants,” Schmidt explained.
“This situation exemplifies the ongoing issues related to coal combustion, which leads to air pollution, solid waste generation, and these water discharges. The more we persist, the more we exacerbate problems like this.”
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