IOWA CITY, Iowa — Iowa's second largest power company agreed Wednesday to drastically cut pollution at several coal-fired power plants under a Clean Air Act settlement that's expected to make the air safer and easier to breathe around the state.
Interstate Power and Light, Alliant Energy's Iowa subsidiary, will install and continuously operate pollution controls at its two largest coal-fired plants in Iowa under the consent decree filed in federal court. The equipment — which is already in place in Lansing and must be installed in Ottumwa by Dec. 31, 2019 — is expected to cost the utility $620 million and slash key pollutants that impact respiratory and cardiovascular health and contribute to acid rain, smog and haze, federal officials said.
In addition, the utility will be required to retire or convert five other coal-fired plants — Cedar Rapids, Burlington, Dubuque, Clinton and Marshalltown — to cleaner-burning natural gas on a rolling basis through 2025.
While Interstate Power and Light already has made some of the changes and was planning to do others, the settlement can be enforced by a judge, sets tight limits for emissions and details monetary penalties for violations.
The company will also pay a $1.1 million fine and spend $6 million on a range of environmental mitigation projects under the settlement. When fully implemented, the U.S. Department of Justice and the Environmental Protection Agency project the changes will cut annual emissions of sulfur dioxide and nitrogen oxide by 36,000 tons.
"It's going to reduce pollution not by a little bit but by a lot," said Assistant U.S. Attorney General John Cruden, who oversees the Environment and Natural Resources Division.
U.S. Attorney Kevin Techau of the Northern District of Iowa said the changes will have a "huge impact on the quality of life for Iowans," making the air easier to breathe for young children, the elderly and others with respiratory illnesses.
Federal officials praised Interstate Power and Light for negotiating reforms rather than fighting the enforcement action, which started in 2011 when the Sierra Club filed a notice accusing the company of violating the Clean Air Act. The U.S. Environmental Protection Agency later took over the case.
Interstate Power and Light, which provides electric service to 525,000 customers and natural gas to 225,000 customers in Iowa and Minnesota, can choose from five environmental mitigation projects. Options include installing additional solar energy capacity or replacing its fleet of utility trucks with hybrid trucks.
The moves settle a complaint also filed Wednesday alleging that Interstate Power and Light violated the Clean Air Act when it made major modifications to the Ottumwa and Lansing plants that increased emissions in 2006 and 2009, respectively. The company failed to obtain necessary permits to make the changes and didn't install the best available pollution controls required by the act, the complaint alleged. Interstate Power and Light denied wrongdoing.
"The terms we negotiated are consistent with our long-term plan for clean energy," company president Doug Kopp said. "We settled with the EPA to avoid unnecessary delays and ongoing uncertainty associated with litigation."
The company noted that scrubber systems recently installed at Lansing and Ottumwa are expected to cut sulfur dioxide emissions by 90 percent. The Ottumwa plant also will install large equipment known as selective catalyctic reduction, which is expected to reduce nitrogen oxide emissions by a similar amount.
Sierra Club attorney Wallace Taylor said the settlement, expected to take effect after a 30-day comment period, will expedite the company's push toward cleaner energy.
"It is a big deal," he said. "It means we're on the way to making a big dent in greenhouses gases, which is important because that's what causes climate change."