cility's basic design or purpose, IEPA properly considered Prairie State's objectives for the proposed Facility and concluded that the use of a particular 30-year coal supply under common ownership and control is an inherent aspect of the proposed project. The Board is satisfied that IEPA took a sufficiently hard look at the Facility to determine whether further emissions reductions would be achievable while still meeting Prairie State's purpose.

The Board rejects Petitioners' argument that IEPA erred as a matter of law when it found that Integrated Gasification Combined Cycle ("IGCC") is a potentially applicable process alternative for controlling SO2 and NOx, but nevertheless excluded IGCC at step 2 of the top-down method. Although Agency guidance generally counsels in favor of a full and detailed impacts analysis at step 4 for each control alternative found to be technically feasible at step 2, there is one narrow exception. A full analysis is not required where there are two or more alternatives with comparable control efficiencies and one is more costly than the other. IEPA's rationale in the present case for rejecting full evaluation of IGCC as a more costly, comparably efficient option falls within this guidance.

The Board finds no clear error in IEPA's decision not to include coal washing as a supplemental control method (for possible further reduction of SO2 emissions). Petitioners have not shown clear error in IEPA's central conclusion that any benefits of coal washing are outweighed by coal washing's cost, energy, and environmental impacts.

Although IEPA's analysis of dry cooling as an alternative method for controlling PM emissions from the cooling towers is less than optimal (IEPA's narrative analysis is less than ordinarily expected of a full step 4 impacts analysis), Petitioners have not taken the additional step that they are required to take, which is to put before the Board evidence that the facts are contrary to the reasoning stated in IEPA's narrative analysis.

The Board rejects Petitioners contention that IEPA failed to provide notice to the public and to adequately consider the Petitioners' concern that the Facility's anticipated use of approximately one million tons of limestone per year to run the SO2 controls may destroy habitat of the Eastern Narrow Mouth Toad if the limestone is mined from the toad's habitat. IEPA's reliance on the Illinois Department of Natural Resources' biological opinion, and IEPA's ultimate conclusion that the proposed technology does not pose a "significant or unusual environmental impact," is supported by the facts in the record and does not constitute clear error. The Board also concludes that the information that became available to IEPA after the close of public comment did not raise substantial new questions that warrant a reopening of the comment period, and the Board finds no error in IEPA's failure to do so.

Petitioners' argument that IEPA did not consider available variations in the technology selected for control of SO2 is rejected - IEPA did in fact consider technological variations and related performance data. The Board also rejects Petitioners' argument that IEPA clearly erred by failing to perform a separate BACT analysis for sulfuric acid mist distinct from the BACT analysis for SO2 emissions. Petitioners have failed to point to evidence of error in the permitting authority's analytic methodology, which is the kind of technical determination with respect to which the Board ordinarily defers to the permitting authority.

The Board rejects Petitioners' contention that IEPA should have "updated" its NOx BACT determination to take into account new information submitted after the close of public comment. The regulations governing the administrative record generally do not require the issuer of an EPA permit to supplement the record with information submitted by the public after the close of the public comment period. Although there are circumstances in which significant new information that becomes available following the close of public comment appropriately should be considered in finalizing a permit's terms, Petitioners have not demonstrated how the post-comment period information upon which they rely is sufficiently significant to call into question IEPA's permit limit. IEPA did consider, prior to issuing its decision, information substantially similar to the new information upon which Petitioners rely.

The Board rejects Petitioners' contention that IEPA provided no record justification for the use of a safety factor in setting the PM and NOx emissions limits. IEPA specifically identified variability in the data as a reason for its use of a safety factor in setting the emissions limits.

The Board rejects Petitioners's contention that the total PM10 limit was not established through a BACT top-down analysis. The pollutant at issue is particulate matter. PM10 is not a separate pollutant; instead, it is merely an indicator for PM and consists of two constituent parts: condensable and filterable PM10. It is beyond dispute that IEPA performed a top-down BACT analysis for PM, which included the available and applicable control methods for the filterable and condensable components of PM10.

The Board rejects Petitioners' objection that the Permit's conditions providing for downward adjustment to the total PM10 limit after analysis of the Facility's actual performance violates PSD permitting requirements. IEPA specifically concluded that there is scientific uncertainty about whether the PM10 emission limit can be achieved in practice. Under these circumstances, the use of an adjustable limit, constrained by certain parameters, and backed by a worst case air quality analysis, is a reasonable approach.

Contrary to Petitioners' contentions, the Permit does not provide an exemption from numeric emissions limits for emissions of filterable PM, total PM10, volatile organic matter, sulfuric acid mist, and fluorides from all BACT limits during periods of startup, shutdown and malfunction. The Permit specifically establishes "secondary limits," which are also numeric limits, for these pollutants "for purposes of BACT." These secondary BACT limits were derived directly from the primary heat input BACT limits and do not authorize emissions greater than the primary limits would allow at the units' rated heat input capacity.

The Board rejects Petitioners' request for review of IEPA's surrogate approach to analyzing the Facility's compliance with the new National Ambient Air Quality Standards ("NAAQS") for ozone stated as an 8-hour standard and to the new NAAQS for PM stated as PM2.5 standards. IEPA did precisely what Appendix W (40 C.F.R. pt. 51, App. W §§ 6.2.1(c), 6.2.2.1(c)) recommends for determining compliance with the 8-hour ozone and PM2.5 NAAQS. IEPA followed Region 5's and EPA's guidance regarding the "most suitable approach" to be used on a case-by-case basis, which was to use the 1-hour ozone and PM10 modeling as a surrogate.

The Board also rejects Petitioners argument that IEPA improperly disregarded projected violations of the NAAQS for SO2 and PM10 based on a "culpability" analysis

that excluded violations falling below certain significant impact levels (“SILs”). IEPA's exclusion of de minimis impacts falling below the SILS is consistent with the statutory text and with longstanding Agency guidance.

The Board rejects Petitioners's argument that IEPA failed to adequately notify the public of the adverse impact finding made by the federal land manager ("FLM") responsible for the Mingo Class I area. Where the permit issuer provides notice to the FLM that complies with 40 C.F.R. § 52.21(p)(1) and the FLM does not make an adverse impact determination and provide such determination to the permit issuer in the time frame specified in 40 C.F.R. § 52.21(p)(3), the regulations do not require the permit issuer to subsequently provide a new notice to the public when the FLM issues a later adverse impact finding.

The Board finds that the delegation of authority to IEPA to issue federal PSD permits does not provide an exception from the obligation to coordinate PSD review with review under the National Environmental Policy Act, 42 U.S.C. §§ 4321-4370e ("NEPA"). The Board holds that a state permitting agency exercising delegated authority has sufficiently coordinated when the agency concludes that any ongoing NEPA review does not pertain to the portions of the facility subject to PSD regulation.

Executive Order 12898 instructs federal agencies to address, as appropriate, “disproportionately high and adverse human health or environmental effects of [their] programs, policies, and activities on minority and low-income populations ***." Environmental justice issues must be considered in connection with the issuance of PSD permits by both the Regions and states acting under delegated authority. The Board rejects Petitioners contention that IEPA failed to adequately consider the environmental justice issues raised during the public comment period, including the comments regarding whether the proposed Facility would have a disproportionate impact on residents of East St. Louis.

Before Environmental Appeals Judges Scott C. Fulton, Edward E. Reich, and Anna L. Wolgast.

Opinion of the Board by Judge Wolgast:

On June 8, 2005, the American Bottom Conservancy, American Lung Association of Metropolitan Chicago, Clean Air Task Force, Health and Environmental Justice-St. Louis, Lake County Conservation Alliance, Sierra Club and Valley Watch (collectively, "Petitioners") filed a petition requesting that the Environmental Appeals Board ("Board") grant review of certain conditions of a prevention of significant deterioration (“PSD") permit, Permit No. 189808AAB (the "Permit"). The Illinois Environmental Protection Agency ("IEPA")1 issued the Permit to

1 IEPA administers the PSD program in Illinois pursuant to a delegation of authority from U.S. EPA Region 5 (the "Region"). See Delegation of Authority to State Agencies, 46 Fed. Reg. 9580 (Jan. 29, 1981); In re Zion Energy, LLC, 9 E.A.D. 701, 701 n. 1 (EAB 2001). Permits issued by states acting with delegated authority are considered EPA-issued permits. In re SEI Birchwood, Inc., 5 E.A.D. 25, Continued

Prairie State Generating Company, LLC ("Prairie State"). The Permit would authorize Prairie State to construct the Prairie State Generating Station (the "Facility"), which is a proposed 1500-megawatt ("MW") coal-fuel powered electricity generating plant to be located in Washington County, Illinois, approximately five miles east north-east of Marissa.

For the reasons explained below, we deny Petitioners' request that we undertake review of the Permit's conditions.

A. Project Description

I. BACKGROUND

The proposed Facility consists of two coal-fired steam electric generating units, each with a nominal generating capacity of 750 net megawatts. Project Summary at 1. Each unit includes a coal-fired boiler with a nominal rated heat input capacity of approximately 7450 million Btu/hr ("MMBtu”). Id. The fuel will be supplied as pulverized coal (i.e., coal ground to a fine powder immediately before being blown, along with the combustion air, into the boiler). Id. "The principal fuel for the boilers will be Illinois coal (Herrin No. 6).” Id. The Facility would be located at the mouth of a new underground coal mine, which will be the principal source of coal fuel used at the Facility. Id.

B. Statutory and Regulatory Background

Congress enacted the PSD provisions of the Clean Air Act ("CAA") in 1977 for the purpose of, among other things, “insur[ing] that economic growth will occur in a manner consistent with the preservation of existing clean air resources." CAA § 160(3), 42 U.S.C. § 7470(3). The statute requires preconstruction approval in the form of a PSD permit before anyone may build a new major stationary source of air pollutants or make a major modification to an existing source if such source is located in either an "attainment" or "unclassifiable" area. CAA §§ 107, 160-169B, 42 U.S.C. §§ 7407, 7470-7492. The PSD permitting program regulates air pollution in "attainment" areas, where air quality meets or is cleaner than the

(continued)

26 (EAB 1994); see also In re Hadson Power 14-Buena Vista, 4 E.A.D. 258, 259 (EAB 1992). Because IEPA acts as EPA's delegate in implementing the federal PSD program within the State of Illinois, the Permit is considered an EPA-issued permit for purposes of federal law, and is subject to review by the Board pursuant to 40 C.F.R. § 124.19. See In re Hillman Power Co., LLC, 10 E.A.D. 673, 675 (EAB 2002); In re Three Mountain Power, LLC, 10 E.A.D. 39, 40 n.1 (EAB 2001); In re Kawaihae Cogeneration Project, 7 E.A.D. 107, 109 n.1 (EAB 1997); In re Commonwealth Chesapeake Corp., 6 E.A.D. 764, 765 n.1 (EAB 1997); In re W. Suburban Recycling & Energy Ctr., LP, 6 E.A.D. 692, 695 n.4 (EAB 1996).

national ambient air quality standards ("NAAQS"), as well as areas that cannot be classified as "attainment" or "non-attainment" (i.e., "unclassifiable" areas). Id.; see also In re EcoEléctrica, L.P., 7 E.A.D. 56, 59 (EAB 1997); In re Commonwealth Chesapeake Corp., 6 E.A.D. 764, 766-67 (EAB 1997).

The NAAQS are "maximum concentration 'ceilings" for particular pollutants, "measured in terms of the total concentration of a pollutant in the atmosphere." U.S. EPA Office of Air Quality Planning & Standards, New Source Review Workshop Manual at C.3 (Oct. 1990) (Draft) ["NSR Manual"].2 The PSD permitting requirements are pollutant-specific, which means that a facility may emit many air pollutants, but only one or a few may be subject to PSD review, depending upon a number of factors including the amount of emissions of each pollutant by the facility. NSR Manual at 4. NAAQS have been set for six criteria pollutants: sulfur oxides,3 particulate matter ("PM"),4 nitrogen dioxide ("NO2"),5 carbon monoxide ("CO"), ozone, and lead. See 40 C.F.R. §§ 50.4-50.12. Prairie State's proposed Facility will be located in Washington County, Illinois, which is located in an area designated attainment for meeting the NAAQS for SO2 and either attainment or unclassifiable for particulate matter (measured as PM10), CO, ozone (1-hour standard), and NO2. 40 C.F.R. § 81.314.

2 The NSR Manual has been used as a guidance document in conjunction with new source review workshops and training, and as a guide for state and federal permitting officials with respect to PSD requirements and policy. Although it is not a binding Agency regulation, the NSR Manual has been looked to by this Board as a statement of the Agency's thinking on certain PSD issues. E.g., In re RockGen Energy Ctr., 8 E.A.D. 536, 542 n.10 (EAB 1999), In re Knauf Fiber Glass, GmbH, 8 E.A.D. 121, 129 n.13 (EAB 1999).

3 Sulfur oxides are measured as sulfur dioxide (SO2). 40 C.F.R. § 50.4(c).

4 "Particulate matter, or 'PM' is 'the generic term for a broad class of chemically and physically diverse substances that exist as discrete particles (liquid droplets or solids) over a wide range of sizes."" In re Steel Dynamics, 9 E.A.D. 165, 181 (EAB 2000) (quoting 62 Fed. Reg. 38,652, 38,653 (July 18, 1997)). For purposes of determining attainment of the NAAQS, particulate matter is measured in the ambient air as particulate matter with an aerodynamic diameter of 10 micrometers or less, referred to as PM10. 40 C.F.R. § 50.6(c).

5 A facility's compliance with respect to nitrogen dioxide is measured in terms of emissions of any nitrogen oxides (NOx). 40 C.F.R. § 52.21(b)(23); In re Haw. Elec. Light Co., 8 E.A.D. 66, 69 n.4 (EAB 1998). The term nitrogen oxides refers to a family of compounds of nitrogen and oxygen. The principal nitrogen oxides component present in the atmosphere at any time is nitrogen dioxides. Combustion sources emit mostly nitric oxide, with some nitrogen dioxides. Composition sources emit mostly nitric oxide, with some nitrogen dioxide. Upon entering the atmosphere, the nitric oxide changes rapidly, mostly to nitrogen dioxide. Alaska Dept. of Envtl. Conservation v. EPA, 540 U.S. 461, 470 n.1 (2004) (quoting EPA, Preservation of Significant Deterioration for Nitrogen Oxides, 53 Fed. Reg. 40,656, 40,656 (Oct. 17, 1988)).

6 A facility's compliance with respect to ozone is measured in terms of emissions of volatile organic compounds ("VOCs"). 40 C.F.R. § 52.21(b)(23).