2024-27942. Air Plan Partial Approval and Partial Disapproval; Wyoming; Regional Haze Plan for the Second Implementation Period

Table 1—Sources, Units, and Associated Pollutants That May Affect Visibility at Class I Areas Where No Four-Factor Analysis Was Performed

Source	Unit(s)	Associated pollutant(s)
Jim Bridger (PacifiCorp)	1, 2	NO X , SO 2 , PM.
Jim Bridger (PacifiCorp)	3, 4	SO 2 , PM.
Naughton (PacifiCorp)	1, 2	NO X , SO 2 , PM.
Naughton (PacifiCorp)	3	NO X , PM.
Dave Johnston (PacifiCorp)	1, 2	NO X , SO 2 , PM.
Dave Johnston (PacifiCorp)	4	PM.
Wyodak (PacifiCorp)	1	NO X , SO 2 , PM.
Laramie River Station (Basin Electric)	1-3	PM.
Laramie Portland Cement (Mountain Cement Company)	Kilns 1, 2	SO 2 .
Elk Basin Gas Plant (Contango Resources, Inc.)	Engines (9) and incinerator	PM.
Elk Basin Gas Plant (Contango Resources, Inc.)	Engines (9)	SO 2 .
Elk Basin Gas Plant (Contango Resources, Inc.)	Incinerator	NO X .

Although we stated in our proposed rule that Wyoming failed to justify the lack of a four-factor analysis of NO_X and PM emission control measures for Lost Cabin Gas Plant, we are not carrying that finding forward into our final rule. Based on our consideration of a comment we received and on our further review of Wyoming's 2022 SIP submission, we conclude that because the State's Q/d analysis ^[5] shows that the possible impact of the facility's NO_X and PM emissions on visibility at Class I areas is very small, Wyoming reasonably elected to conduct a four-factor analysis only for SO₂ control measures for this facility, and not for NO_X and PM control measures. Therefore, the lack of a four-factor analysis of NO_X and PM emissions controls for Lost Cabin Gas Plant is not a reason for our disapproval of the State's long-term strategy.^[6]

Second, Wyoming relied on unsupported rationales and failed to document the technical basis (including cost, engineering, and emissions information) ^[7] of its decision not to include any emission control measures in its long-term strategy for the sources listed in table 2. In evaluating the cost of potential control measures for some of these sources, Wyoming used unsubstantiated cost inputs, relied on unjustifiably low estimates of control technology efficiencies, and miscalculated the level of achievable emission reductions. These methodological errors undercut the technical support for Wyoming's cost analyses and the State's resulting determinations that control measures for these sources would not be cost-effective. In other instances, the State provided no reasoning, technical data, or cost information to support its conclusions. For the reasons detailed in our proposed rule and in the RTC document,^[8] these methodological errors and unsupported technical bases, considered collectively, prevent the EPA from determining that the State's long-term strategy is adequate to make reasonable progress toward meeting the national visibility goal.

Table 2—Sources, Units, and Associated Pollutants Where the State Failed To Document the Technical Basis of Its Determinations of the Emission Reduction Measures Necessary To Make Reasonable Progress

Source	Unit(s)	Associated pollutant(s)
Dave Johnston (PacifiCorp)	4	SO 2 .
Laramie Portland Cement (Mountain Cement Company)	Kilns 1, 2	NO X .
( print page 95124)
Green River Works (TATA Chemicals)	Calciner 1, Calciner 2	NO X , PM.
Elk Basin Gas Plant (Contango Resources, Inc.)	Engines (9)	NO X .
Elk Basin Gas Plant (Contango Resources, Inc.)	Incinerator	SO 2 .
Lost Cabin Gas Plant (Burlington Resources)	Trains 2, 3	SO 2 .

Third, Wyoming unreasonably rejected emission control measures for Elk Basin Gas Plant and Cheyenne Fertilizer Facility (listed in table 3). Wyoming made no determination that these control measures were not cost-effective (based on the cost per ton of emissions reduced); ^[9] nor did it explain why these measures were otherwise unwarranted under the four statutory factors.^[10] The cost-effectiveness values of these control measures are below the level that the EPA and the states generally found to be reasonable in the first implementation period, even without adjusting for inflation. Instead of justifying its rejection of these control measures based on the four statutory factors, Wyoming cited declining emission trends, its belief that these sources will not increase their emissions during the second implementation period, and the presence of existing control technologies at the facilities (which the State notably did not determine to be effective for purposes of making reasonable progress).^[11] As we explained in the context of the 2017 Regional Haze Rule revisions, “a state that elects to consider an additional factor . . . must consider it in a reasonable way that does not undermine or nullify the role of the four statutory factors in determining what controls are necessary to make reasonable progress.” ^[12] Wyoming improperly relied on these other considerations to reject controls that its four-factor analyses showed to be cost-effective and otherwise reasonable.

Within its 2022 SIP submission, Wyoming conceded that based on the four-factor analyses it conducted for Elk Basin Gas Plant and Cheyenne Fertilizer Facility, these sources may warrant further analysis of the measures necessary to make reasonable progress.^[13] Wyoming stated it would submit more detailed analyses in the context of its regional haze second implementation progress report due in 2025. However, nothing in the CAA or RHR allows states to avoid their obligation to determine the measures necessary to make reasonable progress through consideration of the four statutory factors by delaying decision-making to a future date.^[14] For these reasons, and as further detailed in our proposed rule and in the RTC document,^[15] we find that Wyoming's long-term strategy does not include the measures necessary to make reasonable progress because Wyoming unreasonably rejected control measures for Elk Basin Gas Plant and Cheyenne Fertilizer Facility.

Table 3—Sources, Units, and Associated Pollutants and Emission Control Technology Where the State Unreasonably Rejected Emission Reduction Measures

Source	Unit(s)	Associated pollutant(s)	Emission control technology
Elk Basin Gas Plant (Contango Resources, Inc.)	Engines (9)	NO X	Low emission combustion.
Cheyenne Fertilizer Facility (Dyno Nobel, Inc.)	ENG004, ENG005 (engines)	NO X	Low emission combustion.
Cheyenne Fertilizer Facility (Dyno Nobel, Inc.)	CTW001, CTW003 (cooling towers)	PM	Upgraded Mist Eliminators.

( print page 95125)

Fourth, as explained in our proposed rule and in the RTC document,^[16] the overarching justifications that Wyoming provided for not including any emission control measures in its long-term strategy are either not adequately supported or lack foundation in the CAA and RHR. Following its evaluation and rejection of emission control measures for individual sources, Wyoming explained its overall reasoning for not including any measures in its long-term strategy to make reasonable progress for the regional haze second implementation period.^[17] The State asserted that such measures could impose economic hardships on sources, negatively affect rural communities, force energy producers out of the market, harm ratepayers, and cause grid instability. However, the State's reliance on these purported economic impacts does not reflect reasoned analysis because Wyoming provided no analyses, data, or other evidence to support its generalized and unsubstantiated assertions. Similarly, Wyoming provided no support for its declaration that requiring additional controls would not lead to visibility improvements at Class I areas. Finally, Wyoming pointed to contributions to visibility impairment from sources outside its control; past and projected emission reductions resulting from other regulatory programs; and that the State's Class I areas are below the adjusted uniform rate of progress (a tracking metric to help states assess the amount of progress they are making towards the national visibility goal over time in each Class I area). As further explained in our proposed rule and in the RTC document, Wyoming's consideration of those factors was not reasonably moored to the statute and regulations.

In addition to disapproving the State's long-term strategy, we are disapproving Wyoming's reasonable progress goals under 40 CFR 51.308(f)(3) and its consultation with Federal Land Managers under 40 CFR 51.308(i). As detailed in our proposed rule and in the RTC document,^[18] compliance with these requirements is dependent on compliance with the long-term strategy provisions in 40 CFR 51.308(f)(2).

III. Final Action

For the reasons stated in the proposed rule, in the RTC document, and in this document, we are partially approving and partially disapproving Wyoming's 2022 SIP submission.

We are disapproving the following components of Wyoming's 2022 SIP submission relating to CAA section 169A:

• Long-term strategy (40 CFR 51.308(f)(2));
• Reasonable progress goals (40 CFR 51.308(f)(3)); and
• FLM consultation (40 CFR 51.308(i)).

We are approving the following components of Wyoming's 2022 SIP submission relating to CAA section 169A:

• Calculations of baseline, current, and natural visibility conditions, progress to date, and uniform rate of progress (40 CFR 51.308(f)(1));
• Reasonably attributable visibility impairment (40 CFR 51.308(f)(4));
• Progress report requirements (40 CFR 51.308(f)(5) and 40 CFR 51.308(g)); and
• Monitoring strategy and other implementation plan requirements (40 CFR 51.308(f)(6)).

IV. 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 partially approves and partially disapproves 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 Orders 12866 (58 FR 51735, October 4, 1993) and 14094 (88 FR 21879, April 11, 2023);
• 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 inExecutive Order 13132 (64 FR 43255, August 10, 1999);
• Is not subject toExecutive Order 13045 (62 FR 19885, April 23, 1997) because it approves a state program;
• Is not a significant regulatory action subject toExecutive 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).

Executive Order 12898 (Federal Actions To Address Environmental Justice in Minority Populations and Low-Income Populations, 59 FR 7629, Feb. 16, 1994) directs Federal agencies to identify and address “disproportionately high and adverse human health or environmental effects” of their actions on communities with environmental justice (EJ) concerns to the greatest extent practicable and permitted by law. Executive Order 14096 (Revitalizing Our Nation's Commitment to Environmental Justice for All, 88 FR 25251, April 26, 2023) builds on and supplements E.O. 12898 and defines EJ as, among other things, the just treatment and meaningful involvement of all people, regardless of income, race, color, national origin, or Tribal affiliation, or disability in agency decision-making and other Federal activities that affect human health and the environment.

The State did not evaluate EJ considerations as part of its SIP submittal; the CAA and applicable implementing regulations neither prohibit nor require such an evaluation. EPA performed an EJ analysis, as is described in the proposed action 89 FR 63030 (August 1, 2024) in the section titled, “Environmental Justice.” The analysis was done for the purpose of providing additional context and information about this rulemaking to the public, not as a basis of the action. In addition, there is no information in the record upon which this decision is based inconsistent with the stated goal ( print page 95126) of E.O. 12898/14096 of achieving EJ for communities with EJ concerns.

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 January 31, 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
• Carbon monoxide
• Greenhouse gases
• Incorporation by reference
• Intergovernmental relations
• Lead
• Nitrogen dioxide
• Ozone
• Particulate matter
• Reporting and recordkeeping requirements
• Sulfur oxides
• Volatile organic compounds

Dated: November 22, 2024.

KC Becker,

Regional Administrator, Region 8.

For the reasons stated in the preamble, the Environmental Protection Agency is amending 40 CFR part 52 as follows:

PART 52—APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

1. The authority citation for part 52 continues to read as follows:

Authority: 42 U.S.C. 7401 et seq.

Subpart ZZ—Wyoming

2. In § 52.2620, the table in paragraph (e) is amended by adding and entry for “(36) XXXVI” at the end of the table to read as follows:

§ 52.2620

Identification of plan.

* * * * *

(e) * * *

Rule No.	Rule title	State effective date	EPA effective date	Final rule citation/date	Comments
*         *         *         *         *         *         *
(36) XXXVI	Wyoming State Implementation Plan, Second Planning Period	2022	1/2/2025	[insert Federal Register citation], 12/2/2024	Excluding the following: Chapters 3.4, 7, 8, 10, 11, 12, 13, 14, 15, and appendix C-E, G-M. EPA disapproved the portions of Wyoming's 2022 SIP submission relating to CAA section 169A and 40 CFR 51.308(f)(2): long-term strategy; 40 CFR 51.308(f)(3): reasonable progress goals; and 40 CFR 51.308(i): FLM consultation.