The Iowa Department of Natural Resources is taking comment until Oct. 15 on a draft air permit approval for Interstate Power and Light that would cover changes at the coal-fired Prairie Creek Generating Station.
“Interstate Power and Light Company (IPL) is submitting this Prevention of Significant Deterioration (PSD) construction permit application for EP001 (Boilers 1 & 2) to recognize the facility’s intent to install a CO CEMS to comply with the industrial boiler MACT (40 CFR 63 Subpart DDDDD) CO emission limit of 340 ppm by volume 30 day rolling average that will be in effect January 31, 2016,” said a DNR permit document. “To be consistent with the rule, IPL is requesting the CO emission limit be clarified to state the 0.3 lb/MMbtu limit is based on a 30-day rolling average to become effective once the CO CEMS is certified.
“In addition, IPL will add calcium bromide injection system to both boilers to control mercury and sootblowers to clean the economizers. At IPL’s request, this permit will be amended to eliminate all references to the combustion of old corrugated cardboard (OCCR). This fuel has historically never been fired in these boilers and IPL has no intention to burn them in the future in light of recent consent agreement (Civil Action C15-0061) filed 7/15/15.”
Alliant Energy (NYSE: LNT) in its Aug. 6 quarterly Form 10-Q report said that its Interstate Power and Light (IPL) unit is already well along on complying with a consent decree worked out with various parties and filed with the U.S. District Court for the Northern District of Iowa in July. That is the decree that the Iowa DNR was referring to.
Under the decree, IPL is required to install the following emissions controls:
- 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 (placed in service in June 2015 and in 2010, respectively); and
- Selective catalytic reduction (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 electricity generating units:
- M.L. Kapp Generating Station by Aug. 31, 2015 (switched the fuel type from coal to natural gas in June 2015);
- Prairie Creek Unit 4 by June 1, 2018;
- Burlington Generating Station by Dec. 31, 2021; and
- Prairie Creek Units 1 and 3 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 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, 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.