Environmental groups oppose a draft permit from the Iowa Department of Natural Resources for the Ottumwa Generating Station. (Photo via Google Maps)
Several environmental groups are urging the Iowa Department of Natural Resources to deny a wastewater permit for an Ottumwa coal plant because, they say, it “unlawfully” avoids federal guidelines for coal combustion leachate discharges.
DNR and Alliant Energy, which owns the plant, say the permit request updates a “technical issue” from a previously issued permit for the Ottumwa Generating Station and the federal guidelines in question cannot be upheld because the station does not discharge leachate.
Sierra Club Iowa Chapter, Iowa Environmental Council and Environmental Law and Policy Center submitted comments on DNR’s published draft permit for the station, and urged DNR to require supplemental information from the company to “meet the requirements of the Clean Water Act.”
The groups argued DNR needed to apply the effluent limitation guidelines, referred to in the comments as ELG, that the U.S. Environmental Protection Agency finalized in 2024 to strengthen the wastewater discharge standards for coal-fired power plants.
The expanded rules created more stringent limitations for discharges like leachate, which is water that interacts with the waste material of burning coal as it is collected in a type of landfill and becomes contaminated with the coal ash byproducts.
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Iowa DNR does not enforce effluent limitation guidelines in the draft permit, which the environmental groups said is “unlawful” and also harmful to communities downstream of the facility that could be exposed to the heavy metals and other pollutants discharged.
But DNR, and Alliant, the parent company of Interstate Power and Light Company which owns the station, say the rules don’t apply to the permit because the station does not discharge leachate.
No leachate at the generating station
The environmental groups point to the previously approved permit for the generating station, and the DNR’s rationale on the 2025 draft permit, which both mention leachate as part of the discharge from one of the generating station outfalls.
Melissa McCarville, a senior communications partner with Alliant Energy, said the DNR “incorrectly includes” mention of the landfill leachate in the rationale of the permit changes.
“The Ottumwa Generating Station does not produce leachate and the plant is not allowed to discharge leachate from any landfill under its permit,” McCarville said in an email. “The requested permit amendment does not change that.”
Tammie Krausman, communications chief and public information officer for DNR, confirmed the agency’s error on the rationale. She said leachate “used to be covered under the permit” but because of the EPA’s strengthened effluent limitation rules from last year, Interstate Power decided to “no longer have a discharge option for leachate at Ottumwa Generating Station.”
Krausman said the generating station, and thus the 2025 permit draft, do “not allow for the discharge of managed or unmanaged leachate.”
“The DNR only has the authority to apply leachate ELGs to wastestreams that contain leachate (managed or unmanaged),” Krausman said in an email. “No such wastestreams exist at IPL Ottumwa Generating Station. As such, the facility is prohibited from discharging leachate at the site covered by the IPL Ottumwa Generating Station (National Pollutant Discharge Elimination System) permit.”
Where is the leachate?
The same groups issued a notice of intent to sue Iowa Power and Light in March, claiming it lacked the necessary permits to discharge polluted groundwater into the Des Moines River.
This issue dealt with the station’s nearby coal-ash landfill, the Ottumwa Midland Landfill, which processes the waste material from burning coal, the process of which creates leachate.
The groups alleged the landfill was discharging polluted groundwater from below the coal ash pond into a nearby wetland, which eventually drains into the Des Moines River.
The environmental groups were worried about the water entering the river because of data that indicated the water was polluted with arsenic, boron, iron, zinc and other pollutants.
Interstate Power responded to the threat of lawsuit by agreeing to stop discharging the groundwater and instead transport the water, and leachate, to be used for evaporation at the coal plant, or to be treated at the Ottumwa Water Pollution Control Facility before it is discharged into the Des Moines River.
Iowa Environmental Council said in a press release at the time that trucking the water to the city for treatment would be “expensive and ineffective.”
The group also said city water treatment plants are “not equipped to properly handle” coal ash contaminants
Joshua Smith, the senior staff attorney with Sierra Club, said in an email to Iowa Capital Dispatch the solution was like “dumping used motor oil into the city sewer.”
“It might be marginally better than dumping it into the river, but it’s generally unlawful because the treatment system isn’t designed to remove large amounts of motor oil,” Smith said as an example.
The groups, in their comments to DNR over the permit for the generating station, said the DNR “circumvent(s) the ELG Rule’s requirements” by allowing Interstate Power to transport leachate and underlining groundwater to the city.
“Although the (landfill’s permit with the city of Ottumwa) includes numeric discharge limits for several pollutants typically found in leachate wastewater discharges, the permit limits are woefully inadequate to ensure compliance with EPA’s ELG Rule.”
According to the comments, the discharge limits of contaminants outlined in the permit with the city are “many orders of magnitude greater than allowed under the ELG Rule” or allow “continued, indefinite discharges” of some heavy metals and toxic pollutants.
“The (permit’s) numeric limits are not a lawful substitute for ELG compliance” the comments said.
The comments also point to a section of EPA’s explanation of the effluent limitation guideline rule that says transporting leachate to a publicly owned treatment works is “irrelevant” to the application of the effluent limitation guideline’s treatment requirements.
The comments said allowing coal-plant operators to circumvent the effluent limitation rules by doing so would result in “the disparate treatment of direct dischargers, unfairly shifting the financial and public health burden of compliance to municipalities, interfering with the operation of (publicly owned treatment works), and undermining the Clean Water Act’s goal of eliminating pollution discharges.”
Smith said the comments from the environmental groups were made based on the application materials that were publicly available, and said “there may be other documents, facts, explanations, etc that change the analysis, but we do not believe DNR can lawfully issue the draft permit as written.”
McCarville did not respond to Iowa Capital Dispatch’s question about about Interstate Power’s decision to transport leachate and groundwater drainage to the Ottumwa Water Pollution Control Facility and the facility’s ability to deal with its possible contaminants.
“Ottumwa Generating Station is in compliance with the permits issued by the Iowa DNR and we remain fully committed to protecting water quality in the Des Moines River,” McCarville said in an email.
A representative from Ottumwa Water Pollution Control Facility did not respond to a request for comment.
Michael Schmidt, general council for Iowa Environmental Council, said the situation is also “indicative of the problems that result from burning coal.”
“We have a whole bunch of coal ash landfills around the state, and they are producing this kind of waste on an ongoing basis, and DNR needs to be regulating that to make sure that our groundwater and our drinking water is not being polluted,” Schmidt said.
The environmental groups also requested a public hearing on the draft permit so those who live near, recreate on the river, or receive municipal water downstream of the facility can share their perspectives on “protecting the Des Moines River from toxic and heavy metal discharges from the facility.”
Krausman confirmed Thursday the department plans to hold a public hearing on the permit, and was working to finalize details.