1 

Earthjustice • Environmental Law and Policy Center • Sierra Club 

June 20, 2014 

VIA E-MAIL AND REGULAR MAIL 

Dean Studer, Hearing Officer 

Illinois EPA 

1021 North Grand Avenue East 

P.O. Box 19276 

Springfield, Illinois 62794-9276 

Dean.Studer@Illinois.gov

Re: Proposed Revision of the Illinois State Implementation Plan for Regional Haze 

Dear Mr. Studer, 

Please accept these comments submitted by Earthjustice, the Environmental Law and 

Policy Center (“ELPC”), and the Sierra Club on the proposal to revise the Illinois State 

Implementation Plan (“SIP”) for regional haze to incorporate a variance granted by the Illinois 

Pollution Control Board (“PCB”) to Illinois Power Holdings, LLC (“IPH”) and AmerenEnergy 

Medina Valley Cogen, LLC (“Medina Valley”). 

As explained below, the Illinois Environmental Protection Agency (“IEPA”) should not 

finalize the proposed SIP revision and should not submit it to the U.S. Environmental Protection 

Agency (“EPA”) because it does not meet the applicable requirements of the Clean Air Act 

(“CAA”). First, the proposed SIP revision, like the original SIP, does not contain the five-factor, 

unit-specific best available retrofit technology (“BART”) determinations required by the CAA. 

Second, even if it were permissible in theory to substitute an alternative program such as 

the Multi-Pollutant Standard (“MPS”) for unit-specific BART limits, IEPA has not met its 

burden to show that the MPS is approvable as a BART alternative because the agency has not 

performed the required modeling of the visibility impacts from the MPS compared to BART. 

Third, the Illinois Pollution Control Board granted variances to Ameren Energy 

Resources, and later to IPH and Medina Valley, from the Illinois Multi-Pollutant Standard, 35 Ill. 

Adm. Code 225.233, from 2015 through the year 2019, that significantly weaken the MPS’ 

requirements of reductions in haze-forming sulfur dioxide (“SO2”) relied upon by EPA in 

approving the Illinois regional haze SIP. The MPS sets out annual fleet-wide sulfur dioxide 

limits applicable to the fleet of 7 coal-fired power plants that, at the time of the MPS’ adoption, 

were operated by Ameren Corporation and its subsidiaries (“Ameren”). The 5 Ameren plants 

still in operation—Coffeen, Duck Creek, E.D. Edwards, Joppa, and Newton—are now owned 

and operated by IPH; the 2 former Ameren plants that retired in 2011—Hutsonville and 

Meredosia—are owned by Medina Valley. The variances make the MPS’ fleet-wide SO2 limits 

significantly less stringent than those EPA approved in its final rule. This development 

completely undermines the rationale for finding, pursuant to 40 C.F.R. § 51.308(e)(2)(i), that 

Illinois’ implementation of the MPS to reduce SO2 emissions from the former Ameren fleet’s 
2 

Illinois coal-fired power plants will “achieve greater reasonable progress than would be achieved 

through the installation and operation of” BART at the fleet’s BART-subject plants. Rather, 

because of the variances, the MPS will no longer require SO2 reductions from the former 

Ameren coal fleet during the period of the first long-term strategy for regional haze (i.e., before 

2018, see 40 C.F.R. § 51.308(f)) that are greater than the reductions that would result from 

requiring IPH to install and operate BART on its BART-subject plants. 

As a result of these three legal deficiencies, EPA cannot approve the proposed SIP 

revision. Instead of finalizing a plan that EPA cannot lawfully approve, IEPA should conduct 

source-specific BART determinations for the IPH units subject to BART. 

I. BACKGROUND 

 Recognizing that manmade haze diminishes visibility and degrades the integrity of many 

of the nation’s national parks and wilderness areas, Congress in 1977 amended the Clean Air 

Act, “declar[ing] as a national goal the prevention of any future, and the remedying of any 

existing, impairment of visibility in mandatory class I Federal areas which impairment results 

from manmade air pollution.” See 42 U.S.C. § 7491(a)(1); see also 40 C.F.R. pt. 81, subpt. D 

(listing the 156 protected Class I areas, including certain national parks, wilderness areas, and 

national memorial parks, as well as certain international parks). Among other things, Congress 

mandated that EPA adopt regulations that would require states to develop SIPs containing 

measures necessary to make reasonable progress toward the national goal of improving visibility, 

One of the cornerstones of the haze SIPs is the installation and operation of BART at BARTeligible sources1

 that could be reasonably anticipated to cause or contribute to visibility 

impairment in a Class I area (referred to as sources “subject to BART”). 42 U.S.C. § 7491(a)(4), 

(b)(2)(A). 

 In 1999 – after many years of deferred action on widespread, regionally homogenous 

haze – EPA promulgated the Regional Haze Rule. Regional Haze Regulations, 64 Fed. Reg. 

35,714 (July 1, 1999). Under that Rule, states are directed to submit SIPs containing emissions 

limitations representing BART and schedules for compliance for each source subject to BART. 

See 40 C.F.R. § 51.308(e). States must determine BART for each source based on a case-bycase analysis, id. § 51.308(e)(1)(ii), and must require “each source subject to BART . . . to install 

and operate BART as expeditiously as practicable, but in no event later than 5 years after 

approval” by EPA of the state’s Regional Haze SIP, id. § 51.308(e)(1)(iv). 

 On June 24, 2011, Illinois submitted a proposed Regional Haze SIP to EPA. 77 Fed. 

Reg. 3966, 3970 (Jan. 26, 2012). In its proposed SIP, Illinois stated that, based on modeling 

completed by the Midwest Regional Planning Organization (“MRPO”), it determined that 

emissions sources in the state cause or contribute to visibility degradation in 19 national parks 

and wilderness areas (defined in the CAA as “Class I areas”).2

 To comply with the BART 

provisions of the Regional Haze Rule, Illinois evaluated which BART-eligible emissions sources 

                                                     

1

 A source is BART-eligible if it is a stationary source within one of 26 enumerated categories, was not in operation 

before August 7, 1962 but was in existence on August 7, 1977, and has the potential to emit 250 tons per year or 

more of any pollutant. 42 U.S.C. § 7491(b)(2)(A), (g)(7). 

2

 Illinois SIP Submittal, Attachment 1 to Docket ID No. EPA-R05-OAR-2011-0598-0002. 
3 

within the state cause or contribute to visibility impairment in those Class I areas and are thus 

subject to BART. Illinois identified 11 such sources, including 9 coal-fired power plants.3

 

 Instead of evaluating and determining BART for all 9 coal-fired power plants subject to 

BART, Illinois proposed for 7 of the 9 plants that two state emissions trading rules implemented 

in tandem – the MPS, 35 Ill. Adm. 225.233, and the Combined Pollutant Standard (“CPS”), 35 

Ill. Adm. Code 225.291-299 – be relied on as an “alternative” to BART.4 These 7 plants 

included 3 plants from the original Ameren fleet: Coffeen, Duck Creek, and E.D. Edwards.5 

Each of these 3 plants is currently regulated by the MPS, as are the 4 additional plants in the 

original Ameren fleet.6 The MPS requires that this fleet’s emissions of SO2 and nitrogen oxides 

(“NOx”) be reduced to meet certain fleet-wide average emission rates each year.7 The MPS’ 

fleet-wide average emission rates “are intended to allow the companies the flexibility to meet the 

fleet-wide emission limits in the most cost-effective manner” by reducing SO2 and NOx 

emissions more at some plants than at other plants.8

 The SO2 limits for the Ameren fleet vary by 

year; the fleet’s average SO2 emissions cannot exceed 0.25 lb/MMBtu between 2015-2016 and 

cannot exceed 0.23 lb/MMBtu from 2017 onwards. 

At the same time, because the MPS requires reductions at all 7 of the original Ameren 

plants instead of just the 3 plants with units subject to BART, Illinois proposed that EPA find 

that its “approach will yield much larger reductions of NOx and SO2 than will implementation of 

BART controls on just subject to BART emission units.”9

 Thus, according to Illinois, the greater 

fleet-wide reductions that the MPS requires of the original Ameren fleet (together with similar 

reductions that the MPS and CPS require of two other fleets, owned by Midwest Generation and 

Dynegy at the time the MPS and CPS were adopted) constitute “greater reasonable progress than 

would have resulted from the installation and operation of BART” at the BART-subject units in 

those fleets.10

 After EPA proposed to approve the Illinois Regional Haze SIP, ELPC, Sierra Club and 

other organizations filed comments opposing EPA’s approval.11 The commenters first argued 

that under the plain language of Section 169A of the Clean Air Act, 42 U.S.C. § 7491, BART is 

a mandatory measure that must be implemented to achieve reasonable progress toward 

restoration of natural visibility conditions.12 Second, the commenters noted several reasons why 

Illinois’ implementation of the MPS/CPS will not achieve greater reasonable progress toward 

natural visibility conditions than BART and thus could not constitute a lawful BART alternative 

                                                     

3

 Technical Support Document, Attachment 2 to Docket ID No. EPA-R05-OAR-2011-0598-0002, at 12-22. 

4

 Illinois SIP Submittal at 19-20. For the remaining two BART-subject plants, Illinois proposed BART 

determinations. Technical Support Document at 31-38. 

5

 Illinois SIP Submittal at 20; Technical Support Document at 22, 28. 

6 Technical Support Document at 28-30.

7 Id. at 24-25. 8 Id. at 25. 9 Id. 

10 Responsiveness Summary, Attachment 9 to Docket ID No. EPA-R05-OAR-2011-0598-0002, at 5 (citing 40 

C.F.R. § 51.308(e)). 

11 Comments of ELPC, et al., Docket ID No. EPA-R05-OAR-2011-0598-0004. 12 See id. at 6-7. 
4 

under the Regional Haze Rule.13 Among other reasons, ELPC and Sierra Club pointed out that 

Illinois compared the MPS/CPS to “presumptive BART” limits for BART-subject units that were 

“at least 2 to 3 times higher than recent BART requirements” imposed after source-specific 

BART determinations, and that Illinois had failed to make similar source-specific BART 

determinations for any of the BART-subject plants regulated by the MPS or the CPS.14 ELPC 

and Sierra Club’s comments thus argued that, “if Illinois had conducted proper BART analyses, 

it is virtually certain that it would have determined that the MPS/CPS is not ‘better’ than BART 

for subject sources.”15

 On July 6, 2012, EPA issued the final rule approving and promulgating the Illinois 

Regional Haze SIP. 77 Fed. Reg. 39,943, 39,943-48. In response to ELPC and Sierra Club’s 

comments, EPA stated that it “continues to believe that Illinois’ plan limits power plant 

emissions as well as would be achieved by directly requiring [BART]” and thus that the Illinois 

SIP “satisfactorily addresses Clean Air Act section 169A and Regional Haze Rule requirements.” 

Id. at 39,943. Although EPA acknowledged that the MPS/CPS allows BART-subject units to 

meet less stringent SO2 and NOx emission limits than a BART requirement, EPA stated that 

“Illinois is requiring control across a universe of sources that includes many sources that are not 

subject to BART, thereby providing reductions that under EPA’s rules and BART guidelines on 

alternative measures can compensate for any shortfall in control at BART units.” Id. at 39,945. 

 In addition, to address ELPC and Sierra Club’s comment that the “presumptive BART” 

limits analyzed by Illinois were 2 to 3 times higher than actual, source-specific BART limits 

would be, EPA prepared a “further analysis” using lower emission limits “of whether Illinois’ 

requirements, addressing a substantial number of sources, can be expected to provide greater 

reasonable progress toward visibility protection than application of BART to the more limited 

number of units subject to a requirement for BART.” Id. at 39,945. This analysis was 

summarized in a memorandum dated May 29, 2012, by John Summerhays, EPA Region 5 

Attainment and Maintenance Section, entitled “Comparison of Illinois Power Plant Emission 

Reductions to Reductions from Source-Specific Best Available Retrofit Technology” 

(hereinafter the “Summerhays Memo”), Docket ID No. EPA-R05-OAR-2011-0598-0007.16

 For its further analysis in the Summerhays Memo, EPA assumed a SO2 emissions limit 

of 0.06 lb/MMBtu, which it defined as an average of recent Best Available Control Technology 

(“BACT”) limits for SO2 from EPA’s national RACT/BACT/LAER Clearinghouse database.17 

This limit is 2.5 times lower than the 0.15 lb/MMBtu “presumptive BART” limit that Illinois 

took from EPA’s 2005 BART Guidelines, 40 C.F.R. pt. 51, App. Y.18 Using the same 

methodology, EPA developed a set of similarly lower NOx emissions limits as well.19 Although 

its analysis did not yield source-specific BART determinations, EPA asserted that assuming an 

                                                     

13 See id. at 7-14. 14 Id. at 7-12. 15 Id. at 10. 16 EPA placed the Summerhays Memo in the rulemaking docket at the time that it finalized the rule approving and 

promulgating the Illinois Regional Haze SIP. The analysis in the Summerhays Memo was not made available to the 

public during the public comment period on EPA’s proposed approval of the Illinois Regional Haze SIP. 17 Summerhays Memo at 1. 

18 Technical Support Document at 23-24. 

19 See Summerhays Memo at 1. 
5 

average BACT limit as equivalent to BART would create a “conservative estimate of the 

emissions of BART on a source-specific basis,” because “the emission limits representing 

BART, which by definition apply to relatively old existing units, are unlikely to be lower than 

the limits that would apply to new units and would in many cases be significantly higher.”20

 For all three fleets regulated by the MPS/CPS – Ameren, Dynegy, and Midwest 

Generation – EPA found that the fleet-wide SO2 and NOx reductions under full implementation 

of those rules in the year 2017 would exceed the SO2 and NOx reductions that would be 

achieved if those fleets’ BART-subject units would be required to install and operate BART, 

even using EPA’s “conservative estimate” of lower BART limits than Illinois presumed.21 With 

respect to SO2 emissions from the Ameren fleet, EPA’s analysis showed that full 

implementation of the MPS would compel SO2 emission reductions of 111,997 tons, as 

compared to emission reductions totaling 74,348 tons of SO2 if BART were required.22

After EPA approved the Illinois regional haze SIP, the Illinois Pollution Control Board 

issued an opinion and order on September 20, 2012 granting Ameren “a variance requiring 

compliance with an overall annual SO2 emission rate of 0.35 lb/mmBtu from 2013 through 

2019” on average at each of its power plants.23 Under the terms of the variance, Ameren would 

not be required to meet the MPS 2015 fleet-wide average emission rate of 0.25 lbs./mmBtu until 

January 1, 2020, and it would not be required to meet the MPS 2017 fleet-wide average emission 

rate of 0.23 lbs./mmBtu until January 15, 2020.24 

Subsequent to the September 2012 Order, Ameren entered into a tentative deal to transfer 

ownership of two EGUs to Medina Valley, a subsidiary of Ameren, and five EGUs to Illinois 

Power Holdings, LLC, which is owned by a subsidiary of Dynegy. Ameren and IPH petitioned 

the PCB to grant to the new owners substantially the same variance from the SO2 limits that had 

been granted in the September 2012 Order to the prior owners.25 Over the objection of public 

interest groups, the PCB granted a variance to IPH and Medina Valley.26 IEPA now proposes to 

revise the regional haze SIP to include this variance for the former Ameren fleet. 

II. ARGUMENT 

The proposed SIP revision suffers from three separate legal flaws, each of which would 

prevent EPA from approving the revision. First, the revised SIP continues to ignore the statutory 

mandate to include source-specific BART determinations for all units subject to BART. Second, 

even if BART could be satisfied by alternative programs such as the MPS, a state must 

demonstrate that the alternative program will make greater reasonable progress than would 

BART; under these facts, the only permissible way to make this showing is through visibility 

                                                     

20 Id. 21 Id. at 1-6. 22 Id. at 4. 23 Opinion and Order, Case No. PCB 12-126, at 1-2 (Ill. Pollution Control Bd. Sept. 20, 2012). 

24 Id. at 1-2. The Board further found (based on Ameren’s own variance petition) that of the 7 Ameren power plants 

that are regulated by the MPS, only 5 remain in operation, as Ameren retired its Meredosia and Hutsonville power 

plants at the end of 2011. Id. 25 Opinion and Order, Case No. PCB 14-10, at 1 (Ill. Pollution Control Bd. Nov. 21, 2013). 

26 Id. at 102-04 
6 

modeling, which IEPA failed to do. Third, as a result of the variances, the emissions reductions 

from the MPS will be lower than the reductions that would be achieved by BART at Ameren’s 

fleet, demonstrating that the MPS will not make greater reasonable progress than would BART. 

A. The Proposed SIP Revision Unlawfully Substitutes Fleet-wide Emission 

Limits for the Unit-Specific, Five-Factor BART Analysis Required by the 

CAA. 

The proposed SIP revision continues to violate the CAA mandate that each SIP contain 

emission measures including BART. Instead of conducting the unit-specific BART 

determinations according to the five factors specified by the CAA, IEPA used the MPS to 

purportedly satisfy the BART requirements for the Ameren units subject to BART. The MPS 

requires reductions of SO2 and NOx across the former Ameren fleet of 7 coal-fired power plants 

to meet certain fleet-wide average emission rates each year.27 The MPS’ fleet-wide average 

emission rates “are intended to allow the companies the flexibility to meet the fleet-wide 

emission limits in the most cost-effective manner” by reducing SO2 and NOx emissions more at 

some plants than at other plants.28 

 The Clean Air Act does not permit a state to exempt units from BART without going 

through the exemption process outlined in the statute. The CAA requires that each haze SIP 

“contain such emission limits, schedules of compliance and other measures as may be necessary 

to make reasonable progress toward meeting the national goal [of attaining natural visibility 

conditions] . . . including” BART. 42 U.S.C. § 7491(b)(2)(A). The plain language of the statute 

provides that EPA's regulations “shall require” each SIP to contain various elements, and those 

elements must include BART as a minimum requirement of every haze SIP. Put simply, BART 

is a mandatory floor for each BART-subject unit, not an optional requirement. 

 The statute then specifies the only circumstances in which a source may be exempted 

from BART, none of which apply here. Id. § 7491(c). The CAA provision that allows some 

limited exemptions from BART makes plain that any such exemption must be assessed and 

determined on a source-specific, not a state-wide, basis. Id. § 7491(c)(1). Furthermore, EPA 

may exempt a unit from the source-specific BART requirements of the CAA only where the 

Federal Land Managers concur with the EPA determination of an exemption. We are not aware 

of any statement from Federal Land Managers agreeing with the substitution of MPS limits for 

source-specific BART limits in Illinois. 

 IEPA’s interpretation of the statute, in which a State may substitute an alternative for 

BART on a state-wide or fleet-wide basis cannot be reconciled with Congress specifying very 

narrow standards for exempting a source from BART.29 As a result, IEPA’s continued failure to 

                                                     

27 Id. at 24-25. 28 Id. at 25. 

29 If EPA relies on D.C. Circuit Court of Appeals decisions upholding its interpretation of the statute, that 

application is incorrect as those cases (or at least that interpretation of those cases) fail to conform to the plain 

language of the CAA. To the extent those cases can or must be read to allow EPA to substitute CSAPR for BART 

in the manner proposed here, the cases are incorrect in that the D.C. Circuit Court of Appeals has rewritten the 

statute by failing to give effect to the plain language requiring each SIP to include BART and by disregarding the 

very specific parameters in the statute for exemptions from BART. See Ctr. for Energy & Econ. Dev. v. EPA, 398 
7 

conduct unit-specific BART analyses violates the CAA. To remedy this legal deficiency, IEPA 

should conduct five-factor BART analyses for each unit in the former Ameren fleet subject to 

BART and not finalize or submit to EPA its current proposal. 

B. IEPA Cannot Meet its Burden to Prove that the MPS Makes Greater Reasonable 

 Progress than BART without Conducting Visibility Modeling. 

IEPA has not conducted any modeling comparing the visibility impact from the former 

Ameren fleet under the MPS and BART limits. IEPA cannot meet its legal burden under EPA’s 

regulations until it performs visibility modeling showing that granting variances to IPH and 

Medina Valley will result in no degradation at any Class I area and, averaged across all affected 

Class I areas, the MPS will cause more visibility improvement than BART would. 

EPA’s regulations purport to allow a state to rely on an alternative program in lieu of 

imposing source-specific BART limits if the state demonstrates that the alternative will make 

“greater reasonable progress” than would BART. 40 C.F.R. § 51.308(e)(2), (e)(3). There are 

two ways to make the showing that an alternative program will achieve greater reasonable 

progress. “If the distribution of emissions is not substantially different than under BART,” the 

alternative is deemed to make greater reasonable progress if “the alternative measure results in 

greater emission reductions.” Id. § 51.308(e)(3). However, “if the distribution of emissions is 

significantly different, the State must conduct dispersion modeling to determine differences in 

visibility between BART and the trading program for each impacted Class I area, for the worst 

and best 20 percent of days.” Id. In order to demonstrate “greater reasonable progress,” the 

visibility modeling must show that the alternative program does not cause visibility to decline in 

any Class I area and averaged across all affected Class I areas, the alternative program improves 

visibility relative to BART. Id. § 51.308(e)(3)(i), (ii). 

EPA conceded that the “Part 225 rules reflect substantial averaging across units and 

across facilities.” 77 Fed. Reg. at 3971. EPA’s statement reflects the fact that the MPS is 

designed to allow Ameren the “flexibility” to make emissions reductions at some facilities but 

not others, or to spread the reductions across all facilities, so long as the fleet-wide average 

emission limit is met. The variances do not alter this basic element of the MPS; instead, the 

variance simply increases the overall emissions rate that the former Ameren fleet must meet by 

specific dates. By contrast, BART determinations must be made for each unit, and the 

corresponding emissions limits are particular to that unit and cannot be traded or averaged with 

limits at other units. 

By design, the MPS allows the flexibility to implement emissions reductions other than 

by imposing uniform reductions at specific units subject to BART. IEPA therefore has no basis 

for claiming that the “distribution of emissions [under the MPS] is not substantially different 

than under BART . . . ” 40 C.F.R. § 51.308(e)(3). Instead, IPH, the owner of the units in the 

former Ameren fleet still in operation, is authorized to meet the MPS limits in such a way that 

“the distribution of emissions is significantly different,” id., than it would be if its subject-to-

                                                                                                                                                                           

F.3d 653 (D.C. Cir. 2005); Utility Air Regulatory Group v. EPA, 471 F.3d 1333, 1340 (D.C. Cir. 2006). 

Furthermore, these decisions are not binding precedent in the 7th Circuit, which has jurisdiction over EPA's 

approval of the Illinois regional haze SIP. 
8 

BART units had to meet unit-specific BART limits. If the distribution of emissions is 

significantly different under an alternative program compared to BART, a state must conduct 

visibility modeling in order to meet its burden of securing approval for the alternative program. 

To comply with EPA’s governing regulations, IEPA should at a minimum conduct 

modeling of the visibility impacts from the MPS and BART. However, we urge IEPA to 

abandon its illegal reliance on the MPS to satisfy the BART requirements and instead perform 

source-specific BART determinations for the units in the former Ameren fleet subject to BART. 

C. As a Result of the Variance, the MPS Will Lead to Higher Emissions and Less 

 Reasonable Progress than would BART. 

 The variance from the MPS authorizes the former Ameren fleet to emit greater SO2 

emissions than would be emitted under BART, and thus IEPA cannot prove that the MPS will 

lead to greater reasonable progress than would BART. EPA’s implementing regulations permit a 

state to rely on an alternative program in lieu of imposing source-specific BART limits only if 

the state demonstrates that the alternative will make “greater reasonable progress” than would 

BART. 40 C.F.R. § 51.308(e)(2), (e)(3). “If the distribution of emissions is not substantially 

different than under BART,” the alternative is deemed to make greater reasonable progress if 

“the alternative measure results in greater emission reductions.” Id. § 51.308(e)(3). A State 

must also require that “all necessary emissions reductions take place during the period of the first 

long-term strategy for regional haze,” id. § 51.308(e)(2)(iii), which the regulations define as 

ending in 2018, id. § 51.308(f). 

The Illinois plan contains separate emissions limits for each fleet. The former Ameren 

fleet has its own emissions limits specified in the MPS, and the variance applies to only the 

former Ameren facilities. Since the Illinois plan consists of fleet-specific emissions limits, and 

since the proposed SIP revision applies only to the former Ameren fleet, the BART alternative 

must be judged on the same fleet-by-fleet basis. If the Illinois plan is not better than BART at 

the former Ameren facilities, it cannot be approved by EPA. 

 Both IEPA and EPA assumed that the distribution of emissions would not be 

substantially different under the MPS as compared to BART, and compared only the emissions 

reductions under the MPS and BART at the former Ameren facilities. E.g., 77 Fed. Reg. at 

39946. Even if this assumption were correct, a comparison of the emissions reductions 

demonstrates that BART would reduce emissions more than the MPS (as amended by the 

Ameren variance) would at the former Ameren facilities. 

 The table below recreates the calculation for the remaining Ameren fleet’s SO2 emissions 

for the year 2017 found in Table 1b on page 3 of the Summerhays Memo, but with two updates 

to reflect the new circumstances. First, the table substitutes the 0.35 lb/mmBtu average 

emissions rate now applicable under the IPH and Medina Valley variances. 
9 

Second, the table below excludes the purported “emissions reductions” at the Meredosia 

and Hutsonville units that have now been retired for several years due to economic reasons,30

along with emissions reductions from Edwards Unit 1, which is now being operated only for grid 

reliability purposes subject to a short-term System Support Resource (“SSR”) agreement with 

MISO.31 These plants have retired or are retiring before the MPS limits at issue here are 

implemented, so the MPS is not driving emissions reductions at those plants. Moreover, the 

Meredosia and Hutsonville units were not even purchased from Ameren by IPH and should not 

be included in any analysis of emissions reductions at the former Ameren fleet. 

Table 1. Emissions Reductions from BART vs. Variances from the MPS for Former 

Ameren Fleet 

 Table 1 indicates that BART would reduce SO2 emissions by 74,348 tons. This value is 

taken, unaltered, from EPA’s calculations. See, e.g., 77 Fed. Reg. at 39946. Table 1 updates the 

reductions achievable under the MPS to reflect that the variance authorizes Ameren to emit SO2 

at a higher fleet-wide average rate of 0.35 lb/MMBtu. As a result, the MPS would now reduce 

SO2 emissions by 69,555 tons. Accordingly, BART would reduce SO2 emissions from the 

former Ameren fleet by 4,793 tons more than would the MPS (with the variances). 

                                                     

30 See Opinion and Order, Case No. PCB 14-10, at 7, 10 (Ill. Pollution Control Bd. Nov. 21, 2013) (noting that the 

September 2012 PCB Order required that Meredosia and Hutsonville remain shut down through December 2020); 

see also Jeffrey Tomich, Ameren Corp. Prepares to Close Two Old Power Plants in Illinois, ST. LOUIS POSTDISPATCH, Oct. 5, 2011, available at http://www.stltoday.com/business/local/ameren-corp-prepares-to-close-twoold-power-plants-in/article_0a82d93f-52c8-5f43-a2d9-303e8ef438dc.html. 31 FERC Docket No. ER-13-1962-000, Order at 1-2, 6 (Nov. 25, 2013), available at

http://www.ferc.gov/CalendarFiles/20131125200818-ER13-1962-000.pdf. 

BACT (0.06

#/MMBTU)

Plant Unit MMM BTU #/MMBTU Tons

Reduction

(tons) #/MMBTU Reduction (tons)

Coffeen 1 18,570                1.54 14,332                   13,775 0.35 11,082                         

Coffeen 2 37,545                1.49 27,999                   26,873 0.35 21,429                         

Duck Creek 1 22,635                0.97 11,026                   10,347 0.35 7,065                           

E D Edwards 2 17,222                1.7 14,666                   14,149 0.35 11,652                         

E D Edwards 3 15,972                1.21 9,683                        9,203 0.35 6,888                           

Joppa 1 13,548                0.51 3,441            0.35 1,070                           

Joppa 2 16,258                0.51 4,139            0.35 1,294                           

Joppa 3 15,396                0.51 3,947            0.35 1,253                           

Joppa 4 13,402                0.52 3,488            0.35 1,143                           

Joppa 5 15,094                0.52 3,932            0.35 1,291                           

Joppa 6 16,063                0.52 4,182            0.35 1,371                           

Newton 1 40,631                0.45 9,046            0.35 1,936                           

Newton 2 38,533                0.46 8,826            0.35 2,083                           

Total 74,348                                    69,555

Updated Summerhays Memo

Calculation for Ameren Base Year Illinois Strategy With Variances

SO2
10 

 The new calculation in the table above demonstrates that IEPA cannot meet its burden to 

prove that the Illinois Regional Haze SIP will lead to greater reasonable progress than BART 

with respect to the former Ameren fleet’s SO2 emissions. As noted above, EPA approved the 

Illinois haze SIP based on a comparison in the Summerhays Memo between MPS fleet-wide 

average emission rates and what it described as a conservative estimate of source-specific BART 

limits. Even assuming that the Summerhays Memo lawfully interprets the Clean Air Act and 

Regional Haze Rule requirements,32 the Illinois Pollution Control Board’s grant of variances to 

IPH and Medina Valley will require EPA to reverse its finding in the Summerhays Memo that 

Illinois’ implementation of the MPS will achieve greater reasonable progress than would be 

achieved through the installation and operation of BART at the former Ameren fleet’s BARTsubject plants.33 

 IEPA should not finalize and submit to EPA a SIP revision that EPA cannot approve 

because it violates EPA’s regulations requiring a BART alternative to make greater reasonable 

progress than BART. Instead, IEPA should conduct five-factor BART analyses for the former 

Ameren units subject to BART and revise the haze SIP to include such BART limits. 

III. CONCLUSION 

 For the reasons set forth above, Earthjustice, ELPC, and Sierra Club respectfully request 

that IEPA withdraw its proposal and not submit it to EPA for approval. In its place, the agency 

should develop unit-specific BART determinations for the former Ameren units subject to BART 

and propose a SIP revision that includes such BART limits. 

 Please do not hesitate to contact the undersigned if you have any questions about these 

comments. Thank you in advance for your consideration of these important issues. 

 Sincerely, 

 

 Thomas Cmar 

 Earthjustice 

5042 N. Leavitt Street, Suite 1 

Chicago, IL 60625 

 (312) 257-9338 

 tcmar@earthjustice.org

 

Matthew Gerhart 

 Earthjustice 

 705 Second Ave, Suite 203 

Seattle, WA 98104 

                                                     

32 As noted above and for the reasons set forth in their comments on the proposed Illinois Regional Haze SIP, ELPC 

and Sierra Club believe that, even before the variances were granted, EPA’s approval of the Illinois Regional Haze 

SIP was inconsistent with Clean Air Act and Regional Haze Rule requirements. 33 See Summerhays Memo at 1 (citing 40 C.F.R. § 51.308(e)(2)). 
11 

(206) 343-7340 ext. 1024 

 mgerhart@earthjustice.org

Andrew Armstrong 

Environmental Law and Policy Center 

35 East Wacker Drive, Suite 1600 

Chicago, IL 60601 

(312) 795-3738 

AArmstrong@elpc.org

 Eva Schueller 

Sierra Club 

85 Second Street 

San Francisco, CA 94105 

(415) 977-5637 

eva.schueller@sierraclub.org