# Identification of plan.
**AGENCY:**
Environmental Protection Agency (EPA).
**ACTION:**
Final rule.
**SUMMARY:**
The Environmental Protection Agency (EPA) is approving the Regional Haze State Implementation Plan (SIP) revision submitted by the Michigan Department of Environment, Great Lakes, and Energy (EGLE) on August 23, 2021, and supplemented on July 24, 2025, as satisfying applicable requirements under the Clean Air Act (CAA) and EPA's Regional Haze Rule (RHR) for the program's second implementation period. EGLE's SIP submission addresses the requirement that States must periodically revise their long-term strategies for making reasonable progress towards the national goal of preventing any future, and remedying any existing, anthropogenic impairment of visibility, including regional haze, in mandatory Class I Federal areas. The SIP submission also addresses other applicable requirements for the second implementation period of the regional haze program. EPA is taking this action pursuant to sections 110 and 169A of the CAA.
**DATES:**
This final rule is effective on October 6, 2025.
**ADDRESSES:**
EPA has established a docket for this action under Docket ID No. EPA-R05-OAR-2021-0577. All documents in the docket are listed on the *https://www.regulations.gov* website. Although listed in the index, some information is not publicly available, *i.e.,* Confidential Business Information (CBI), Proprietary Business Information (PBI), or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the internet and will be publicly available only in hard copy form. Publicly available docket materials are available either through *https://www.regulations.gov* or at the Environmental Protection Agency, Region 5, Air and Radiation Division, 77 West Jackson Boulevard, Chicago, Illinois 60604. This facility is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding Federal holidays. We recommend that you telephone Matt Rau, at (312) 886-6524 before visiting the Region 5 office.
**FOR FURTHER INFORMATION CONTACT:**
Matt Rau, Air and Radiation Division (AR-18J), Environmental Protection Agency, Region 5, 77 West Jackson Boulevard, Chicago, Illinois 60604, (312) 886-6524, *[email protected].*
**SUPPLEMENTARY INFORMATION:**
Throughout this document whenever “we,” “us,” or “our” is used, we mean EPA.
This supplementary information section is arranged as follows:
I. Background
II. Public Comment Process
III. Summary of Public Comments and EPA's Responses
IV. What action is EPA taking?
V. Statutory and Executive Order Reviews
**I. Background**
On August 23, 2021, EGLE submitted a revision to its SIP to address regional haze requirements for the second implementation period. On July 24, 2025, EGLE submitted a supplement (Supplement) to its original submission providing expanded source-specific analyses and emissions updates. EGLE made this SIP submission to satisfy the requirements of the CAA's regional haze program pursuant to CAA sections 169A and 169B and 40 CFR 51.308.
EPA proposed to approve EGLE's submission into the SIP on June 18, 2025. A full background, the specifics of the Michigan regional haze plan, and EPA's evaluation of the plan are given in the proposed rule and will not be restated in this rule. See 90 FR 25975 (June 18, 2025). EGLE submitted the Supplement in draft for parallel processing on April 3, 2025. Detail on parallel processing is provided in the proposed rule.
In this final action, EPA is affirming that it is now the Agency's policy that, where visibility conditions for a Class I Federal area impacted by a State are below the uniform rate of progress (URP) and the State has considered the four statutory factors, the State will have presumptively demonstrated reasonable progress for the second planning period for that area. EPA acknowledges that this final action reflects a change in policy as to how the URP should be used in the evaluation of regional haze second planning period SIPs but believes that this policy better aligns with the purpose of the statute and RHR: achieving “reasonable” progress towards natural visibility.
As described in the approval of West Virginia's regional haze plan (90 FR 29737, July 7, 2025), EPA has discretion and authority to change its policy. In *FCC* v. *Fox Television Stations, Inc.,* the U.S. Supreme Court plainly stated that an agency is free to change a prior policy and “need not demonstrate . . . that the reasons for the new policy are better than the reasons for the old one; it suffices that the new policy is permissible under the statute, that there are good reasons for it, and that the agency believes it to be better.” 566 U.S. 502, 515 (2009) (referencing Motor *Vehicle Mfrs. Ass'n of United States, Inc.* v. *State Farm Mut. Auto. Ins. Co.,* 463 U.S. 29 (1983)). *See also Perez* v. *Mortgage Bankers Assn.,* 135 S. Ct. 1199 (2015).
The Class I areas impacted by emissions from Michigan sources are all below the 2028 URP, and EGLE's SIP submission demonstrated that the State took into consideration the four reasonable progress factors listed in CAA 169A(g)(1) [^1] with respect to an adequate number of emissions sources. Thus, EPA determines that EGLE's SIP revision is fully approvable.
[^1] The four statutory factors required to be taken into consideration in determining reasonable progress are: the costs of compliance, the time necessary for compliance, and the energy and non-air quality environmental impacts of compliance, and the remaining useful life of any existing source subject to such requirements. CAA section 169(g)(1).
In developing the regulations required by CAA section 169A(b), EPA established the concept of the URP for each Class I area. The URP is determined by drawing a straight line from the measured 2000 to 2004 baseline conditions (in deciviews) for the 20 percent most impaired days at each Class I area to the estimated natural conditions (in deciviews) for the 20 percent most impaired days in 2064. From this calculation, a URP value can be calculated for each year between 2004 and 2064. EPA developed the URP to address the diverse concerns of Eastern and Western States and account for the varying levels of visibility impairment in Class I areas around the country while ensuring an equitable approach nationwide. For each Class I area, States must calculate the URP for the end of each planning period ( *e.g.,* in 2028 for the second planning period). [^2] 40 CFR 51.308(f)(1)(vi)(A). States may also adjust the URP to account for impacts from anthropogenic sources outside the United States and/or impacts from certain wildland prescribed fires. 40 CFR 51.308(f)(1)(vi)(B). Then, for each Class I area, States must compare the reasonable progress goal (RPG) for the 20 percent most impaired days to the URP for the end of the planning period. If the RPG is above the URP, then an additional “robust demonstration” requirement is triggered for each State that contributes to that Class I area. 40 CFR 51.308(f)(3)(ii)(B).
[^2] We note that RPGs are a regulatory construct that we developed to address the statutory mandate in CAA section 169B(e)(1), which required our regulations to include “criteria for measuring `reasonable progress' toward the national goal.” Under 40 CFR 51.308(f)(3)(ii), RPGs measure the progress that is projected to be achieved by the control measures a State has determined are necessary to make reasonable progress. Consistent with the 1999 RHR, the RPGs are unenforceable, though they create a benchmark that allows for analytical comparisons to the URP and mid-implementation-period course corrections if necessary. 82 FR 3091-92 (January 10, 2017).
In the 2017 RHR Revisions, EPA addressed the role of the URP as it relates to a State's development of its second planning period SIP. 82 FR 3078 (January 10, 2017). Specifically, in response to comments suggesting that the URP should be considered a “safe harbor” that relieve States of any obligation to consider the four statutory factors, EPA explained that the URP was not intended to be such a safe harbor. *Id.* at 3099. “Some commenters stated a desire for corresponding rule text dealing with situations where RPGs are equal to (“on”) or better than (“below”) the URP or glidepath. Several commenters stated that the URP or glidepath should be a `safe harbor,' opining that States should be permitted to analyze whether projected visibility conditions for the end of the implementation period will be on or below the glidepath based on on-the-books or on-the-way control measures, and that in such cases a four-factor analysis should not be required.” *Id.*
Other comments indicated a similar approach, such as “a somewhat narrower entrance to a `safe harbor,' by suggesting that if current visibility conditions are already below the end-of-planning-period point on the URP line, a four-factor analysis should not be required.” *Id.* EPA stated in its response that we did not agree with either of these recommendations. “The CAA requires that each SIP revision contain long-term strategies for making reasonable progress, and that in determining reasonable progress States must consider the four statutory factors. Treating the URP as a safe harbor would be inconsistent with the statutory requirement that States assess the potential to make further reasonable progress towards natural visibility goal in every implementation period.” *Id.*
Importantly, EPA's recently adopted policy does not make the URP a safe harbor. The policy merely creates a presumption that the State's second planning period SIP is making reasonable progress for a Class I Federal Area if the State has taken into consideration the four statutory factors of 169A(g)(1) and that area is below the URP. This is consistent with the CAA and RHR.
**II. Public Comment Process**
The public comment period on EPA's proposed approval ended on July 18, 2025. During this period, EPA received three sets of comments. The Power Generators Air Coalition (PGen) and the Mid-Atlantic/Northeast Visibility Union (MANEVU) each submitted a set of comments. Four conservation groups, including the National Parks Conservation Association, the Sierra Club, the Environmental Law and Policy Center, and the Coalition to Protect America's National Parks, submitted a third set of comments and are collectively referred to as “the Conservation Groups” throughout this document.
**III. Summary of Public Comments and EPA's Responses**
EPA has included all comments in the rulemaking docket for this action. The August 25, 2025, Response to Comments (RTC) document is included in the docket for this rulemaking under Docket ID No. EPA-R05-OAR-2021-0577 and provides full and detailed responses to all significant comments that further explain the basis for our final action.
EPA received comments on the proposed rule that covered several topics including, but not limited to, EPA's URP policy, [^3] an “Ask” from a regional planning organization, source selection, analysis of effectively controlled sources, incorporation of measures into the SIP, four-factor analyses, [^4] and the impact on local communities.
[^3] A change in Agency policy was introduced in the approval of West Virginia's regional haze plan. See the April 18, 2025, (90 FR 16478) proposed rule) and the July 7, 2025, (90 FR 29737) final rule.
[^4] Under CAA 169A(g)(1), the four statutory factors are the costs of compliance, the time necessary for compliance, the energy and non-air quality environmental impacts of compliance, and the remaining useful life of any potentially affected sources. See also 40 CFR 51.308(f)(2)(i). An evaluation of potential control options for sources of visibility impairing pollutants based on applying the four statutory factors in CAA section 169A(g)(1) is referred to as a “four-factor” analysis.
PGen's comments, summarized as Comment 1 in the RTC document, are supportive of the proposed approval and EPA's URP policy. EPA concurs with the supportive comments and acknowledges the comment on the URP policy.
MANEVU commented on EPA's URP policy and its “Asks” about the DTE- St. Clair Power Plant. MANEVU's comments and EPA's responses can be found in the RTC document at Comment 2a and 2b and Response 2a and 2b. EPA disagrees with MANEVU's comment as the URP policy is consistent with the statute for the reasons as detailed in Response 2a in the RTC document. EPA also disagrees with MANEVU's comment regarding DTE-St. Clair Power Plant since EGLE fully responded to MANEVU's “Asks” [^5] in the Supplement, section 2.2. See Response 2b in the RTC document for more detail on how EGLE addressed the MANEVU “Asks.”
[^5] The August 25, 2017, and July 27, 2018, MANEVU “Asks”.
The Conservation Groups commented on the economic, public health, and environmental benefits of reducing air pollution through Michigan's regional haze SIP. EPA notes, as explained in Response 3 of the RTC, that EGLE has made progress in reducing visibility-impairing pollution during the second implementation period as demonstrated in the monitoring data collected at the impacted Class I areas. EPA also notes that regional haze program is designed to address visibility concerns and that the National Ambient Air Quality Standards, required by the CAA, protect human health.
The Conservation Groups argue that EGLE's source selection process is arbitrary and capricious since EGLE did not select sources that the Conservation Groups previously recommended for selection. As explained in Response 4 of the RTC, EPA disagrees with the comment. EGLE addressed the requirements of 40 CFR 51.308(f)(2)(i) in its source selection process. EGLE provided information on its source selection process and the results in section 3.2.2 of its Supplement.
The Conservation Groups commented that EPA's proposal to approve EGLE's determination that no additional measures were necessary to make reasonable progress in the second implementation period is arbitrary and capricious. The Conservation Groups claim that EPA has no system to determine how current control technologies or past and potential ongoing emission reductions should be considered when evaluating whether additional measures are necessary. The Conservation Groups also assert that EPA failed to provide adequate public notice because the proposed approval did not provide a metric or an analysis to determine that no additional measures are necessary. See Comment and Response 5 in the RTC document for further details. EPA disagrees with the comment. EPA fully evaluated the information EGLE provided for the sources with current effective control technologies, as well as emission reductions achieved in the second implementation period. In the proposed rule, EPA articulated its rationale in determining how to weigh current effective control measures and emission reductions to approve EGLE's determination that no additional measures are necessary for reasonable progress, citing references to effective control demonstrations in section 3(f) of the 2019 Regional Haze Guidance. See 90 FR 25975 (June 18, 2025). The record in the docket for this rulemaking contains evidence of enforceable emission reductions, as well as EPA's evaluation of emissions reductions in the Technical Support Document (TSD) accompanying the proposed rule. Therefore, EPA disagrees with the Conservation Groups that consideration of these emission reductions was improper in EGLE's determination that no additional measures are necessary to make reasonable progress in the second implementation period. EPA's proposed approval was not arbitrary or capricious because of a lack of a metric and analysis and, as such, does not constitute a failure of public notice.
The Conservation Groups claim that EGLE inappropriately failed to perform four-factor analyses for seven facilities that were improperly determined to be effectively controlled. The Conservation Groups state that the plain language of the CAA and the RHR does not allow EGLE or EPA to eliminate sources from analysis based on assertions that the sources are effectively controlled, but rather requires that States consider the four statutory factors. The Conservation Groups comment that the seven facilities are not effectively controlled and that there are likely cost-effective controls available for each of the sources that would further reduce emissions. The Conservation Groups also commented on two sources that EGLE did not select for analysis, saying EPA did not address or analyze EGLE's decision. As explained in Response 6 of the RTC document, EPA disagrees with this comment. Neither CAA section 169A(b)(2), CAA section 169A(g)(1), nor the RHR prohibit States from forgoing a four-factor analysis based on a source being effectively controlled. As outlined in the 2017 RHR, “the EPA has consistently interpreted the CAA to provide States with the flexibility to conduct four-factor analyses for specific sources, groups of sources or even entire source categories, depending on State policy preferences and the specific circumstances of each State.” 82 FR 3088, January 10, 2017. EPA acknowledges that a State may reasonably decide not to select sources that have recently installed effective controls. EPA notes that if a source's emissions are already well-controlled, it is unlikely that further cost-effective reductions are available. In this case, EGLE evaluated the seven units, including permit limitations, control efficiencies, regulations, actual emissions, past emission trends, and projected 2028 emissions to demonstrate that the existing level of control makes it reasonable to conclude that the controls are effective and that a full four-factor analysis would likely result in the conclusion that no further controls are necessary. EPA also disagrees with the comment regarding two sources EGLE did not select for evaluation of potential additional control measures. EGLE properly addressed the requirements of 40 CFR 51.308(f)(2)(i) in the source selection process it used.
The Conservation Groups commented that EGLE's analyses of existing effective controls are flawed and that EPA's TSD for the proposed rule does not support EPA's proposed approval of EGLE's Regional Haze SIP revision. The Conservation Groups also commented that EGLE did not perform four-factor analyses for specific sources. Detail on the general existing effective controls is given in Comment and Response 6 in the RTC document. Comment and Response 6a in the RTC document provide details on the TSD comment. More detail on the comments regarding the specific sources EGLE did not perform a four-factor analysis on and the responses are found in the RTC document under Comment and Response 6b: J. H. Campbell, Units 1, 2, and 3; Comment and Response 6c: Consumers Energy—Dan E. Karn Units 3 and 4; Comment and Response 6d: Tilden Mining Company Kiln 1; Comment and Response 6e: Belle River Power Plant Units 1 and 2; Comment and Response 6f: St. Mary's Cement—Charlevoix Plant; Comment and Response 6g: Holcim US Lafarge Alpena Plant; and Comment and Response 6h: Neenah Paper Michigan-Munising. EPA disagrees with the assertion that CAA sections 169A(b)(2), (g)(1), or the RHR require every source exceeding the source selection threshold to require a four-factor analysis. EPA disagrees with the commentors on what those portions of the CAA and the RHR require of selected sources. Specifically, States have the flexibility to determine that a source is effectively controlled. As detailed in Response 6 in the RTC document, CAA section 169A(b)(2) does not discuss which sources, types of sources, or groups of sources must be considered to determine reasonable progress. Reasonable progress is addressed in CAA section 169A(g)(1) in that States must “take into consideration” the four statutory factors. Similarly, the RHR does not give minimum source selection criteria. EPA disagrees that the TSD does not provide support for the proposed approval. As explained in the TSD and RTC, EPA's approval of the Michigan regional haze plan is based on the consideration of all evidence provided in EGLE's submission and additional information provided in the docket. EPA also disagrees with the notion that a four-factor analysis is required for each of the specific units that were identified by the Conservations Groups. In summary, EPA finds that EGLE reasonably concluded that the units are effectively controlled and that conducting a four-factor analysis would not likely result in additional measures being needed for reasonable progress.
The Conservation Groups also commented with concerns that two specific sources, Midland Cogeneration Venture and EES Coke Battery, were not selected for evaluation of possible additional control measures. Further information regarding these two sources is found in the RTC at Response 6i: Midland Cogeneration Venture and Response 6j: EES Coke Battery. EPA disagrees that Midland Cogeneration Venture and EES Coke Battery should have been selected for analysis and EPA finds that EGLE's source selection process was appropriate and well supported. EGLE sufficiently captured the State's sources with the greatest impact on visibility impairment.
The Conservation Groups expressed concerns about EPA's review of EGLE's four-factor analyses, arguing that EPA did not provide an evaluation of EGLE's analyses or a conclusion as to whether the State's determinations complied with the CAA and RHR. The Conservation Groups also made specific comments on the four-factor analyses for three facilities. A summary of this comment and EPA's full response can be found as Comment and Response 7 in the RTC document. The comments and responses on specific four-factor analyses for Tilden Mining Company LLC Kiln 2, Billerud—Escanaba LLC Power Boiler 11, and Graymont Western Lime Kiln 1 are detailed in the RTC document as Comments and Responses 7a, 7b, and 7c, respectively. EPA disagrees with this comment. As explained in the proposed rule, EPA carefully evaluated EGLE's entire SIP submission, including the Supplement, the comments from the FLM consultation and the State's responses to comments received during the State comment period. EGLE worked directly with the sources in evaluating potential measures and concluded that additional control measures are not necessary for reasonable progress during the second implementation period based on the four factors. EPA disagrees with the comments on these specific facilities. EGLE considered the four statutory factors, current effective control technologies, emission reductions that have already occurred during the second implementation period, and the projected 2028 visibility conditions for Class I areas influenced by emissions from Michigan sources. EPA therefore finds that EGLE reasonably concluded that no additional measures are necessary to make reasonable progress in the second implementation period for any of the three identified sources.
The Conservation Groups commented that EPA did not analyze the impact of haze-forming pollution from Michigan sources on the communities that surround these facilities. See Comment and Response 8 in the RTC document. The RHR does not require an analysis of health impacts. Instead, the National Ambient Air Quality Standards are established to separately protect human health.
The Conservation Groups argue that EPA's URP Policy violates the CAA's visibility provisions. The Conservation Groups comment on specific portions of the CAA and cite several cases. Those comments and EPA's responses are detailed in Comments and Responses 9, 9a, 9b, 9c, and 9d in the RTC document. EPA disagrees with the comments. EPA's URP policy is consistent with the CAA. Pursuant to CAA 169A(a)(4), Congress explicitly delegated the authority to EPA to promulgate regulations regarding reasonable progress towards meeting the national goal. In determining the measures necessary to make reasonable progress, Congress mandated “tak[ing] into consideration the cost of compliance, the time necessary for compliance, and the energy and non-air quality environmental impacts of compliance, and the remaining useful life of any existing source subject to such requirement.” CAA 169A(g)(1). However, nothing in the statute defines what it means “to take into consideration” the four factors under CAA 169A(g)(1). Under this statutory framework, Congress has empowered EPA to give meaning to this statutory phrase. *Loper Bright Enters.* v. *Raimondo,* 603 U.S. 369, 395 (2024). The phrase “to take into consideration” implies a broader process not limited to the four statutory factors, allowing States to weigh other factors, like visibility, to support their determination of whether additional measures are necessary to make reasonable progress at Class I areas. This follows from the fact that reasonable progress requires the improvement of visibility. CAA 169A(b)(2). As such, visibility improvement must be a fundamental part of determining the extent of progress that is considered reasonable. Being below the URP does not relieve a State of its obligations under the CAA and the RHR to make reasonable progress.
The Conservation Groups state that the URP policy is inconsistent with the RHR. The Conservation Groups comment that, “EPA cannot square its new policy with the RHR.” See Comment 10 and Response 10 in the RTC document for further detail. EPA disagrees with this comment. EPA's URP policy is consistent with the RHR. To meet the reasonable progress goal requirements under 40 CFR 51.308(f)(3), the reasonable progress goals established by a State must reflect the measures it deemed to be necessary to make reasonable progress within the applicable implementation period and must be projected to be achieved by the end of the applicable implementation period. Therefore, it is sufficient under 40 CFR 51.308(f)(3) that this SIP establishes reasonable progress goals that reflect visibility conditions that are projected to be achieved by the end of the second planning period.
The Conservation Groups commented that the URP policy violates the procedural requirements of the CAA. The Conservation Groups comment that the URP policy unlawfully departs from national policy, that the URP policy is inconsistent with actions across EPA Regions, that the URP policy effectively revises the RHR, and that EPA must determine if its URP policy has a nationwide scope. The comments and responses on each point are presented in detail as Comments and Responses 11a, 11b, 11c, and 11d in the RTC document. EPA disagrees with each comment. As for the comment noting that the URP policy was announced in a regional action and that this change violates the CAA requirements that SIP actions be consistent with national policy, EPA disagrees that our Regional Consistency regulations at 40 CFR part 56, and 40 CFR 56.5(b) in particular, are relevant to this action. The Conservation Groups mention other regional haze actions in commenting that the URP policy is inconsistent with actions across EPA Regions. EPA disagrees that its change in policy means that all of its actions on second planning period regional haze SIPs that pre-date its proposed approval of the West Virginia second planning period submittal are inconsistent with the URP policy. See 90 FR 29737 (July 7, 2025). The policy is consistent with EPA's long-standing position that the URP is not a “safe harbor.” EPA's policy establishes a presumption that the reasonable progress requirements of the CAA and the RHR are met if the State has taken into consideration the four statutory factors and the visibility impairment for each Class I Area is projected to be below the URP ( *i.e.,* the “glidepath”) at the end of the applicable planning period. Unlike treating the URP as a “safe harbor,” the policy does not exempt or allow a State to evade the requirements of the CAA or the RHR. Treating the URP as a “safe harbor” would exempt States from considering the four statutory factors and would allow States to exclude measures necessary for reasonable progress from the SIP. EPA disagrees with the comment that it must determine if the URP policy has a nationwide scope. EPA notes that this action applies to a SIP submission from one State—Michigan. EPA also states that the comment that EPA “must” publish a finding that this action is “based on a determination of nationwide scope [or] effect” is also unsupported and incorrect. Under CAA section 307(b)(1), 42 U.S.C. 7607(b)(1), a petition for review of an action that is “locally or regionally applicable may be filed only in the United States Court of Appeals for the appropriate circuit,” with one exception: if (i) the action “is based on a determination of nationwide scope or effect” and (ii) “if in taking such action the Administrator finds and publishes that such action is based on such a determination,” then any petition for review must be filed in the D.C. Circuit. The Administrator has not made and published a finding that this action is based on a determination of nationwide scope or effect. Accordingly, any petition for review of this action must be filed in the United States Court of Appeals for the appropriate regional circuit.
The Conservation Groups commented that EGLE's SIP Revision and Supplement do not meet EPA's URP policy for presumptive approval. The Conservation Groups commented on EGLE relying on the IMPROVE Network to satisfy the monitoring requirement of the RHR and EGLE's URP adjustments, as well as on EGLE not addressing additional Class I areas. As explained in Responses 12a, 12b, and 12c of the RTC document, EPA disagrees with these comments. The IMPROVE network was in operation up to the time EGLE submitted its SIP revision. EGLE continues to support and participate in the IMPROVE network. Concerns regarding the future funding of the IMPROVE network are speculative, out of the control of EGLE, and beyond the scope of the basis for our action on EGLE's second planning period SIP. As for the URP adjustments, the RHR at 40 CFR 51.308(f)(1) also provides the option for States to propose adjustments to the URP line for a Class I area to account for visibility impacts from anthropogenic sources outside the United States and the impacts from wildland prescribed fires that were conducted for certain, specified objectives. EGLE provided this analysis for its Class I areas. Under 40 CFR 51.308(f)(2)(ii)(B), States must consider and address the emissions reduction measures identified by other States for their sources as being necessary to make reasonable progress in the mandatory out-of-state Class I area. EGLE analyzed the Class I areas impacted by Michigan emissions using Lake Michigan Air Directors Consortium (LADCO) modeling, as the comment noted. EGLE identified 13 out-of-state Class I areas in addition to its own two Class I areas where Michigan sources contribute to total visibility impairment above 1 percent. EGLE also identified two additional Class I areas within the LADCO States, Voyageurs National Park and Boundary Waters Canoe Area Wilderness in Minnesota, even though Michigan sources contribute below 1 percent to total visibility impairment in each of those areas. The comment included several additional Class I areas. EGLE found no additional measures to be necessary to make reasonable progress in the out-of-state Class I areas. The contribution from Michigan sources would be even smaller at more distant Class I areas so there is no reason to expect that EGLE would find additional measures necessary to make reasonable progress for those distant Class I areas. EPA concludes that EGLE properly considered Michigan sources that are reasonably anticipated to contribute to visibility impairment Class I areas.
**IV. What action is EPA taking?**
EPA is approving the Regional Haze SIP revision submitted by EGLE on August 23, 2021, and supplemented on July 24, 2025, as satisfying applicable requirements under the CAA and RHR for the program's second implementation period.
**V. Statutory and Executive Order Reviews**
Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the CAA and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, EPA's role is to approve State choices, provided that they meet the criteria of the CAA. Accordingly, this action merely approves State law as meeting Federal requirements and does not impose additional requirements beyond those imposed by State law. For that reason, this action:
• Is not a significant regulatory action subject to review by the Office of Management and Budget under Executive Order 12866 (58 FR 51735, October 4, 1993);
• Is not subject to Executive Order 14192 (90 FR 9065, February 6, 2025) because SIP actions are exempt from review under Executive Order 12866;
• Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 *et seq.* );
• Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 *et seq.* );
• Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);
• Does not have federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);
• Is not subject to Executive Order 13045 (62 FR 19885, April 23, 1997) because it approves a State program;
• Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001); and
• Is not subject to requirements of section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the CAA.
In addition, the SIP is not approved to apply on any Indian reservation land or in any other area where EPA or an Indian Tribe has demonstrated that a Tribe has jurisdiction. In those areas of Indian country, the rule does not have Tribal implications and will not impose substantial direct costs on Tribal governments or preempt Tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).
This action is subject to the Congressional Review Act, and EPA will submit a rule report to each House of the Congress and to the Comptroller General of the United States. This action is not a “major rule” as defined by 5 U.S.C. 804(2).
Under section 307(b)(1) of the CAA, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by November 4, 2025. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of this action for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such rule or action. This action may not be challenged later in proceedings to enforce its requirements. (See section 307(b)(2).)
**List of Subjects in 40 CFR Part 52**
Environmental protection, Air pollution control, Incorporation by reference, Intergovernmental relations, Nitrogen oxides, Reporting and recordkeeping requirements, Sulfur oxides.
Dated: August 26, 2025.
Anne Vogel,
Regional Administrator, Region 5.
For the reasons stated in the preamble, title 40 CFR part 52 is amended as follows:
**PART 52—APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS**
**40 CFR Part 52**
1. The authority citation for part 52 continues to read as follows:
**Authority:**
42 U.S.C. 7401 *et seq.*
**40 CFR Part 52**
2. In § 52.1170, the table in paragraph (e) is amended by adding an entry for “Regional Haze Plan for the Second Implementation Plan” after the entry for “Regional Haze Progress Report” to read as follows:
§ 52.1170
(e) * * *
| Name of nonregulatory | Applicable geographic or | State | EPA approval date | Comments |
| --- | --- | --- | --- | --- |
| | | | | |
| * * * * * * * | | | | |
| Regional Haze Plan for the Second Implementation Plan | Statewide | 8/23/2021, | 9/5/2025, 90 FR [Insert
page where the document begins] | Full Approval. |
| | | | | |
| * * * * * * * | | | | |