Alliant subsidiaries make progress on consent decree requirements for coal units

Alliant Energy (NYSE: LNT) in its Nov. 6 quarterly Form 10-Q report offered an update on progress so far in meeting separate Clean Air Act consent decrees worked out by its Wisconsin Power and Light (WPL) and Interstate Power and Light (IPL) subsidiaries.

In April 2013, WPL, along with the other owners of the Edgewater and Columbia coal-fired plants, entered into a consent decree with the U.S. Environmental Protection Agency and the Sierra Club to resolve legal claims relating to Edgewater, Columbia and Nelson Dewey, while admitting no liability. In June 2013, the decree was approved by the U.S. District Court for the Western District of Wisconsin. Under the decree, WPL is required to install the following emission controls systems:

  • Selective catalytic reduction (SCR) system at Edgewater Unit 5 by May 1, 2013 (placed in service in 2012);
  • Scrubbers and baghouses at Columbia Units 1 and 2 by Dec. 31, 2014 (placed in service in 2014);
  • Scrubber and baghouse at Edgewater Unit 5 by Dec. 31, 2016; and
  • SCR system at Columbia Unit 2 by December 31, 2018. 

WPL is also required to fuel switch or retire the coal-fired Nelson Dewey Units 1 and 2 and Edgewater Unit 3 by Dec. 31, 2015, and Edgewater Unit 4 by Dec. 31, 2018. In addition, the decree establishes emission rate limits for SO2, NOx and particulate matter for Columbia Units 1 and 2, Nelson Dewey Units 1 and 2 and Edgewater Units 4 and 5. The decree also includes annual plant-wide emission caps for SO2 and NOx for Columbia, Edgewater and Nelson Dewey.

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.

The consent decree also establishes SO2, NOx and particulate matter emission rate limits with varying averaging times for the Burlington, Lansing, M.L. Kapp, Ottumwa and Prairie Creek stations. In addition, the decree includes calendar-year SO2 and NOx emission caps for the Prairie Creek Generating Station, and calendar-year SO2 and NOx emission caps in aggregate for the Burlington, Dubuque, Lansing, M.L. Kapp, Ottumwa, Prairie Creek and Sutherland stations.

About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.