EPA approving state regional haze air plan for Illinois

The U.S. Environmental Protection Agency is approving revisions to the Illinois State Implementation Plan (SIP), submitted in June 2011, addressing regional haze for the first implementation period.

EPA said in a July 6 Federal Register notice that it received comments disputing its proposed finding regarding best available retrofit technology (BART), but EPA continues to believe that the Illinois plan limits power plant emissions as well as would be achieved by directly requiring BART installations. Therefore, EPA finds that the Illinois regional haze plan satisfactorily addresses Clean Air Act section 169A and Regional Haze Rule (RHR) requirements. EPA is also approving two state rules and incorporating two permits into SIP. This final rule is effective on Aug. 6.

EPA published a notice of proposed rulemaking evaluating Illinois’ submittal on Jan. 26. Using modeling performed by the Lake Michigan Air Directors Consortium (LADCO), Illinois identified 10 power plants and two refineries as having sufficient impact to warrant being subject to a requirement representing BART. Seven of the power plants that were identified as being subject to the requirement for BART are addressed in one of two sets of provisions of Illinois’ rules known as the Combined Pollutant Standards (CPS) and the Multi-Pollutant Standards (MPS). These provisions are included in Illinois’ mercury rules.

These Illinois rules offer the affected utilities (Midwest Generation, Dynegy and Ameren) a choice of limitations, either to include specific mercury emission limitations effective in 2015 with no limits on emissions of SO2 or NOX, or work practice requirements for installation of mercury control equipment in conjunction with limits on SO2 and NOX emissions. Illinois’ submittal included letters from the affected companies choosing the option that includes SO2 and NOX emission limits, which pursuant to Illinois’ rules establishes these as enforceable limits.

  • In the case of Midwest Generation, three of its power plants meet the criteria for being subject to BART, and six plants are governed by the SO2 and NOX limits in the Multi-Pollutant Standards, EPA noted.
  • In the case of Dynegy (NYSE: DYN), one of its power plants meets the criteria for being subject to BART, and four coal-fired power plants are governed by the SO2 and NOX limits in the CPS.
  • In the case of Ameren (NYSE: AEE), three of its power plants meet the criteria for being subject to BART, and five coal-fired plants are governed by the SO2 and NOX limits in the CPS.

In the notice of proposed rulemaking, EPA proposed to conclude that the emission reductions from the MPS and the CPS would be greater than the reductions that would occur with unit-specific implementation of BART. Therefore, EPA proposed to find that the MPS and the CPS suffice to address the BART requirement for the power plants of these three power companies.

Kincaid and Dallman coal plants get separate BART decisions

Illinois also developed source-specific limits to mandate BART for three additional power plants. These limits are adopted into two permits, one for Kincaid Generation’s Kincaid Station and one for City Water, Light, and Power’s (CWLP) Dallman Station and Lakeside Station. CWLP shut down Lakeside in 2009, and the CWLP permit requires that Lakeside never resume operation.

In the July 6 Federal Register notice, EPA addressed several critical comments on its proposed rulemaking related to the Illinois SIP. In one case, a commenter said EPA and the state needed to do unit-by-unit BART determinations, despite the fact the CPS and MPS would mean compliance with the BART standards. “The primary requirement, as specified in Clean Air Act section 169A, is for sources to procure, install, and operate BART,” EPA responded. “In some cases this requirement is met with an analysis of potential controls considering five factors set out in EPA’s regional haze rule (a ‘five-factor analysis’). EPA has determined that this requirement can be met by a state establishing an alternative set of emission limits which mandate greater reasonable progress toward visibility improvement than direct application of BART on a source-by-source basis.”

One commenter expressed a number of concerns about the BART analysis for the Kincaid coal plant. One concern was that the company analyzes wet flue gas desulfurization for a BART scenario based on a relatively high sulfur Illinois coal but analyzes dry sorbent injection based on a low sulfur western coal, biasing the comparison toward a conclusion that use of the control that is least effective at removing SO2 nevertheless achieves the lowest emissions of SO2.

EPA said it agreed that use of higher sulfur coal in the scenario of wet flue gas desulfurization at Kincaid creates a mismatch in comparing this control to the other control options. However, the commenter does not demonstrate that a more appropriate comparison would yield a different result, it added. “Indeed, given how much more expensive wet flue gas desulfurization has been estimated to be for this facility as compared to dry sorbent injection (company estimates of annualized costs of $125 million versus $25 million), EPA believes that a revised BART analysis that used the same fuel for all scenarios, and thus achieved lower emissions with wet flue gas desulfurization, would still show that wet flue gas desulfurization is not cost-effective for this facility,” EPA wrote. “Therefore, EPA continues to believe that Illinois made the appropriate BART determination for this facility.”

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.