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Approval and Promulgation of Implementation Plans; Wyoming; Revisions to SO2

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Environmental Protection Agency (EPA).


Direct final rule.


The Environmental Protection Agency (EPA) is taking direct final action to approve changes to Wyoming's State Implementation Plan (SIP) that update its ambient air quality standards with regard to the 1-hour sulfur dioxide (SO2) and secondary SO2 National Ambient Air Quality Standards (NAAQS). On February 7, 2014, the Wyoming Department of Environmental Quality (WDEQ) submitted to EPA revisions to the Wyoming SIP. Specifically, the State revised Wyoming Air Quality Standards and Regulations (WAQSR) Chapter 2, Section 4, “Ambient standards for sulfur oxides.” In this action, EPA is taking direct final action to approve some of the revisions provided in that SIP submission. This action is being taken in accordance with section 110 of the Clean Air Act (CAA).


This rule is effective on September 29, 2015 without further notice, unless EPA receives adverse comment by August 31, 2015. If adverse comment is received, EPA will publish a timely withdrawal of the direct final rule in the Federal Register informing the public that the rule will not take effect.


Submit comments to EPA Region 8, Office of Partnerships and Regulatory Assistance, Air Program, 1595 Wynkoop Street, Denver, Colorado 80202-1129.

Docket: The EPA has established a docket for this action under Docket Identification Number EPA-R08-OAR-2014-0187. All documents in the docket are listed on the Web site. Although listed in the index, some information may not be publicly available, i.e., Confidential Business Information or other information the disclosure of which is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in the hard copy form. Publicly available docket materials are available either electronically through or in hard copy at EPA Region 8, Office of Partnerships and Regulatory Assistance, Air Program, 1595 Wynkoop Street, Denver, Colorado 80202-1129. The EPA requests that you contact the individual listed in the FOR FURTHER INFORMATION CONTACT section to view the hard copy of the docket. The Regional Office's official hours of business are Monday through Friday, 8:00 a.m.-4:00 p.m., excluding federal holidays. An electronic copy of the State's SIP compilation is also available at​region8/​air/​sip.html.

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Kevin Leone, Air Program, EPA, Region 8, Mailcode 8P-AR, 1595 Wynkoop Street, Denver, Colorado 80202-1129, (303) 312-6227,

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I. General Information

What should I consider as I prepare my comments for EPA?

1. Submitting Confidential Business Information (CBI). Do not submit this information to EPA through or email. Clearly mark the part or all of the information that you claim to be CBI. For CBI information in a disk or CD-ROM that you mail to EPA, mark the outside of the disk or CD-ROM as CBI and then identify electronically within the disk or CD-ROM the specific information that Start Printed Page 45608is claimed as CBI. In addition to one complete version of the comment that includes information claimed as CBI, a copy of the comment that does not contain the information claimed as CBI must be submitted for inclusion in the public docket. Information so marked will not be disclosed except in accordance with procedures set forth in 40 CFR part 2.

2. Tips for Preparing Your Comments. When submitting comments, remember to:

a. Identify the rulemaking by docket number and other identifying information (subject heading, Federal Register date and page number).

b. Follow directions—The agency may ask you to respond to specific questions or organize comments by referencing a Code of Federal Regulations (CFR) part or section number.

c. Explain why you agree or disagree; suggest alternatives and substitute language for your requested changes.

d. Describe any assumptions and provide any technical information and/or data that you used.

e. If you estimate potential costs or burdens, explain how you arrived at your estimate in sufficient detail to allow for it to be reproduced.

f. Provide specific examples to illustrate your concerns, and suggest alternatives.

g. Explain your views as clearly as possible, avoiding the use of profanity or personal threats.

h. Make sure to submit your comments by the comment period deadline identified.

II. Background

Based on its review of the air quality criteria for oxides of sulfur and the primary NAAQS for oxides of sulfur as measured by SO2, the EPA promulgated a revised primary SO2 NAAQS on June 22, 2010 (75 FR 35520-35603). Specifically, the EPA established a 1-hour primary SO2 standard of 75 parts per billion (ppb), based on the 3-year average of the annual 99th percentile of 1-hour daily maximum concentrations. On May 22, 1996, EPA promulgated a 3-hour secondary SO2 standard of 0.5 parts per million (ppm), not to be exceeded more than once per calendar year (61 FR 25580).

On February 7, 2014, the WDEQ submitted to EPA SIP revisions updating WAQSR Chapter 2, “Ambient Standards,” Section 4, “Ambient standards for sulfur oxides.” The State revised this chapter to incorporate the 2010 1-hour SO2 standard into the Wyoming SIP and updated the secondary 3-hour SO2 standard of 0.5 parts per million (ppm), not to be exceeded more than once per calendar year.

III. Wyoming Revisions and EPA Analysis

As noted, the State revised WAQSR Chapter 2, Section 4 to adopt the 2010 1-hour SO2 standard. The language Wyoming incorporated into Chapter 2, Section 4, part (b) adopts the same language found at 40 CFR 50.17, (“National primary ambient air quality standards for sulfur oxides (sulfur dioxide)).” EPA is taking direct final action to approve this addition into the Wyoming SIP.

Finally, Wyoming adopted the secondary 3-hour SO2 standard into WAQSR Chapter 2, Section 4, part (c). This provision adopts the same language found at 40 CFR 50.5 (“National secondary ambient air quality standard for sulfur oxides (sulfur dioxide))” into the WAQSR. EPA is taking direct final action to approve the addition of this language into the Wyoming SIP.

IV. EPA's Direct Final Action

EPA is taking direct final action to approve revisions, submitted on February 7, 2014, to WAQSR Chapter 2, “Ambient Standards,” Section 4, “Ambient standards for sulfur oxides,” because these revisions are consistent with the federal regulations provided in 40 CFR part 50, sections 5 and 17. In particular, we are approving proposed revisions to WAQSR Chapter 2, Section 4(a)(iii), 4(b), (b)(i), (b)(ii), (c), (c)(i), and (c)(ii). EPA is not taking action on proposed revisions to WAQSR Chapter 2, Section 4(a), 4(a)(i) and (a)(ii) in this rulemaking.

V. Incorporation by Reference

In this rule, the EPA is finalizing regulatory text that includes incorporation by reference. In accordance with requirements of 1 CFR 51.5, the EPA is finalizing the incorporation by reference of the WDEQ rules described in the amendments to 40 CFR part 52 set forth in this document. The EPA has made, and will continue to make, these documents generally available electronically through and/or in hard copy at the appropriate EPA office (see the ADDRESSES section of this preamble for more information).

VI. Statutory and Executive Order Reviews

Under the Clean Air Act, the Administrator is required to approve a SIP submission that complies with the provisions of the Act 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 actions, provided that they meet the criteria of the Clean Air Act. Accordingly, this direct final action merely approves state law provisions as meeting federal requirements and does not propose additional requirements beyond those imposed by state law.

For that reason, this direct final 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);
  • 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 an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);
  • Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001);
  • 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 Clean Air Act; and
  • Does not provide EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).

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).

The Congressional Review Act, 5 U.S.C. 801 et seq, as added by the Small Business Regulatory Enforcement Start Printed Page 45609Fairness Act of 1996, generally provides that before a rule may take effect, the agency promulgating the rule must submit a rule report, which includes a copy of the rule, to each House of the Congress and to the Comptroller General of the United States. EPA will submit a report containing this rule and other required information to the U.S. Senate, the U.S. House of Representatives, and the Comptroller General of the United States prior to publication of the rule in the Federal Register. A major rule cannot take effect until 60 days after it is published in the Federal Register. This action is not a “major rule” as defined by 5 U.S.C. 804(2).

Under section 307(b)(1) of the Clean Air Act, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by September 29, 2015. 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. Parties with objections to this direct final rule are encouraged to file a comment in response to the parallel notice of proposed rulemaking for this action published in the proposed rules section of today's Federal Register, rather than file an immediate petition for judicial review of this direct final rule, so that EPA can withdraw this direct final rule and address the comment in the proposed rulemaking. This action may not be challenged later in proceedings to enforce its requirements. (See CAA section 307(b)(2).)

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List of Subjects in 40 CFR Part 52

  • Environmental protection
  • Air pollution control
  • Carbon monoxide
  • Incorporation by reference
  • Intergovernmental relations
  • Greenhouse gases
  • Lead
  • Nitrogen dioxide
  • Ozone
  • Particulate matter
  • Reporting and recordkeeping requirements
  • Sulfur oxides
  • Volatile organic compounds
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Authority: 42 U.S.C. 7401 et seq.

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Dated: July 1, 2015.

Shaun L. McGrath,

Regional Administrator, Region 8.

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40 CFR part 52 is amended as follows:

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

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

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Subpart ZZ—Wyoming

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2. In § 52.2620, the table titled “State of Wyoming Regulations” in paragraph (c)(1) is amended under Chapter 2 by revising the entry for section 4 to read as follows:

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Identification of plan.
* * * * *

(c) * * *

(1) * * *

State citationTitle/subjectState adopted and effective dateEPA approval date and citation 1Explanations
*         *         *         *         *         *         *
Chapter 2
Section 4Ambient standards for sulfur oxides10/5/2012, 12/19/20127/31/15, [insert Federal Register citation]
*         *         *         *         *         *         *
1 In order to determine the EPA effective date for a specific provision that is listed in this table, consult the Federal Register cited in this column for that particular provision.
* * * * *
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[FR Doc. 2015-18515 Filed 7-30-15; 8:45 am]