IOWA CITY, Iowa (AP) — Iowa's second largest power company will drastically cut pollution at coal-fired power plants under a Clean Air Act settlement expected to make the air cleaner. Interstate Power and Light, a subsidiary of Alliant Energy, will install and continuously operate cutting-edge pollution controls at its biggest Iowa plants, in Ottumwa and Lansing. In addition, the company will retire or convert to natural gas its plants in Cedar Rapids, Dubuque, Burlington, Clinton and Marshalltown. When fully implemented, the changes are expected to cut annual emissions of sulfur dioxide by tens of thousands of tons.Read more on NewsOK.com