The Iowa Department of Natural Resources will be taking comment until Jan. 15 on a draft air permit that covers Interstate Power and Light (IPL) backing out coal as an approved fuel at its M.L. Kapp Generating Station located in Clinton, Iowa.
IPL has applied to amend the main boiler permit and limit facility wide hazardous air pollutant (HAP) emissions below major source thresholds. M.L. Kapp has four sources that emit HAPs – the main boiler, a heating natural gas boiler, a natural gas pre-heater and an emergency generator.
IPL also requested to restrict the main boiler to burning only natural gas and to remove the electrostatic precipitator (ESP) and Low NOx Burners, which were used to control emissions from burning coal. The main boiler was originally permitted in 1978.
The following changes are being made to the main boiler:
- Remove capability to burn coal;
- Remove ESP and Low NOx Burners;
- Limit boiler to burning less than 10,746.943 mmcf per year (63.5% of rated capacity); and
- Remove opacity COMS.
Alliant Energy (NYSE: LNT) in its Nov. 6 quarterly Form 10-Q report offered an update on progress so far on meeting a Clean Air Act consent decree by subsidiary IPL. In July 2015, IPL entered into a consent decree with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa to resolve potential claims regarding CAA issues associated with emissions from IPL’s coal-fired facilities in Iowa, while admitting no liability. In September 2015, the decree was approved by the U.S. District Court for the Northern District of Iowa. Under the decree, IPL is required to install the following emission controls systems:
- Scrubber and baghouse at the Ottumwa Generating Station by Dec. 31, 2015 (placed in service in 2014);
- Scrubber and baghouse at the Lansing Generating Station by Dec. 31, 2016 (scrubber was placed in service in June 2015 and baghouse was placed in service in 2010); and
- SCR system or equivalent NOx reduction system at the Ottumwa Generating Station by Dec. 31, 2019.
IPL is also required to fuel switch or retire the following units:
- M.L. Kapp Generating Station by Aug. 31, 2015 (switched fuel from coal to natural gas in June 2015);
- Prairie Creek Unit 4 (149 MW nameplate) by June 1, 2018;
- Burlington Generating Station (212 MW nameplate) by Dec. 31, 2021; and
- Prairie Creek Units 1 and 3 (64 MW nameplate total) by Dec. 31, 2025.
In addition, IPL is required to either install combined cycle technology at, or retire, the Dubuque and Sutherland stations by June 1, 2019. IPL previously switched the fuel type from coal to natural gas at these units.