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Proposed Rule

Approval and Promulgation of Implementation Plans; Wyoming; Revisions to the Air Quality Standards and Regulations

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Environmental Protection Agency (EPA).


Proposed rule.


EPA is proposing to approve changes to Wyoming's State Implementation Plan (SIP). On February 10, 2014, the Wyoming Department of Environmental Quality (WDEQ) submitted to EPA revisions to the Wyoming SIP. These revisions included edits to Wyoming Air Quality Standards and Regulations (WAQSR) Chapter 3, section 2(d). In this action, EPA is proposing to approve the revisions of this provision into the SIP because the revisions are consistent with Clean Air Act (CAA) requirements. The revisions will correct certain deficiencies related to the correct treatment of excess emissions from sources. EPA will address the remaining revisions from Wyoming's February 10, 2014 submission in separate actions.


Comments must be received on or before August 15, 2014.


Submit your comments, identified by Docket ID No. EPA-R08-OAR-2014-0183, by one of the following methods:

  • Follow the on-line instructions for submitting comments.
  • Email:
  • Fax: (303) 312-6064 (please alert the individual listed in the FOR FURTHER INFORMATION CONTACT if you are faxing comments).
  • Mail: Director, Air Program, Environmental Protection Agency (EPA), Region 8, Mail Code 8P-AR, 1595 Wynkoop Street, Denver, Colorado 80202-1129.
  • Hand Delivery: Director, Air Program, Environmental Protection Agency (EPA), Region 8, Mail Code 8P-AR, 1595 Wynkoop Street, Denver, Colorado 80202-1129. Such deliveries are only accepted Monday through Friday, 8:00 a.m. to 4:30 p.m., excluding federal holidays. Special arrangements should be made for deliveries of boxed information.

Instructions: Direct your comments to Docket ID No. EPA-R08-OAR-2014-0183. EPA's policy is that all comments received will be included in the public docket without change and may be made available online at, including any personal information provided, unless the comment includes information claimed to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected through or email. The Web site is an “anonymous access” system, which means EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an email comment directly to EPA, without going through, your email address will be automatically captured and included as part of the Start Printed Page 41510comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you submit. If EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any defects or viruses. For additional information about EPA's public docket visit the EPA Docket Center homepage at​epahome/​dockets.htm. For additional instructions on submitting comments, go to Section I. General Information of the SUPPLEMENTARY INFORMATION section of this document.

Docket: All documents in the docket are listed in the index. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, will be publicly available only in hard copy. Publicly available docket materials are available either electronically in or in hard copy at the Air Program, U.S. Environmental Protection Agency (EPA), Region 8, 1595 Wynkoop Street, Denver, Colorado 80202-1129. EPA requests that if at all possible, you contact the individual listed in the FOR FURTHER INFORMATION CONTACT section to view the hard copy of the docket. You may view the hard copy of the docket Monday through Friday, 8:00 a.m. to 4:00 p.m., excluding Federal holidays.

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Adam Clark, U.S. Environmental Protection Agency (EPA), Region 8, Mailcode 8P-AR, 1595 Wynkoop Street, Denver, Colorado 80202-1129, (303) 312-7104,

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For the purpose of this document, we are giving meaning to certain words or initials as follows:

(i) The words or initials Act or CAA mean or refer to the Clean Air Act, unless the context indicates otherwise.

(ii) The words EPA, we, us or our mean or refer to the United States Environmental Protection Agency.

(iii) The initials IBR mean or refer to incorporation by reference.

(iv) The initials SIP mean or refer to state implementation plan.

(v) The initials SSM mean or refer to startup, shutdown, and malfunction.

(vi) The words State or Wyoming mean the State of Wyoming, unless the context indicates otherwise.

(vii) The initials WAQSR mean or refer to the Wyoming Air Quality Standards and Regulations.

(viii) The initials WDEQ mean or refer to the Wyoming Department of Environmental Quality.

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 is 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:

  • Identify the rulemaking by docket number and other identifying information (subject heading, Federal Register, date, and page number);
  • Follow directions and organize your comments;
  • Explain why you agree or disagree;
  • Suggest alternatives and substitute language for your requested changes;
  • Describe any assumptions and provide any technical information and/or data that you used;
  • If you estimate potential costs or burdens, explain how you arrived at your estimate in sufficient detail to allow for it to be reproduced;
  • Provide specific examples to illustrate your concerns, and suggest alternatives;
  • Explain your views as clearly as possible, avoiding the use of profanity or personal threats; and
  • Make sure to submit your comments by the comment period deadline identified.

II. Background

In accordance with the requirements of CAA section 110(a)(2)(A), SIPs must contain enforceable emission limitations and, in accordance with the definition of “emission limitations” in CAA section 302(k), such emission limitations must be continuous. In addition, under CAA section 304(a), any person may bring a civil action against any person alleged to have violated (if there is evidence that the alleged violation has been repeated) or to be in violation of an “emission standard or limitation” under the CAA. For the purposes of section 304, “emission standard or limitation” is defined in section 304(f) and includes SIP emission limitations. Thus, SIP emissions limitations can be enforced in a section 304 action and so must be capable of enforcement. SIP provisions that create exemptions such that excess emissions during startup, shutdown, malfunctions (SSM) and other conditions are not violations of the applicable emission limitations are inconsistent with these fundamental requirements of the CAA with respect to emission limitations in SIPs.

WAQSR Chapter 3, section 2(d) created an exemption for particulate matter emissions in excess of a 30 percent opacity standard from diesel engines during startup, malfunction, and maintenance. Because this provision allowed exemptions from the otherwise applicable SIP emission limit, it was inconsistent with CAA requirements.

On June 30, 2011, the Sierra Club filed with the EPA Administrator a petition for rulemaking concerning states' treatment of excess emissions from sources during SSM events (the Petition).[1] In the Petition, the Sierra Club identified existing SIP provisions in 39 states that the Sierra Club considered inconsistent with the CAA, including one provision in the Wyoming SIP. Specifically, the Sierra Club argued that WAQSR Chapter 3, “General Emission Standards,” section 2, “Emission standards for particulate matter,” subsection (d) “is contrary to EPA policy for source category specific rules for startup and shutdown.” [2]

On February 22, 2013, EPA published a proposed rulemaking in which (among other things) we proposed to grant the Petition as it pertained to WAQSR Chapter 3, section 2(d). 78 FR 12460, 12533. We concurred with Sierra Club's assertion that this provision is inconsistent with the requirements of the CAA. For this reason, we proposed to find that WAQSR Chapter 3, section 2(d) is substantially inadequate to meet CAA requirements, and concurrently Start Printed Page 41511proposed to issue a SIP call for this provision.

On February 10, 2014, WDEQ submitted to EPA SIP revisions that included the removal of the problematic language in WAQSR Chapter 3, section 2(d), as well as updates to the State's incorporation by reference (IBR) of federal regulations. The State's IBR updates will be acted upon in a separate rulemaking.

III. Wyoming Revisions and EPA Analysis

Under CAA section 107, states have the primary authority and responsibility to develop and implement SIPs that provide for attainment, maintenance, and enforcement of the National Ambient Air Quality Standards and meet other CAA requirements. Pursuant to CAA section 110(k), EPA has the authority and responsibility to review state SIP submissions to assure that they meet all applicable requirements. CAA section 110(l) prohibits EPA from approving a SIP revision that (among other things) would interfere with any applicable requirement of the CAA. In this instance, the State has elected to revise its existing SIP by editing a previously approved provision that created exemptions from otherwise applicable emission limitations in the SIP.

The State made two edits to WAQSR Chapter 3, section 2(d). Notably, the sentence that read “This limitation shall not apply during a reasonable period of warmup following a cold start or where undergoing repairs and adjustment following malfunction” was struck from the provision.

We consider this change sufficient to correct the provision's inadequacy and to meet the requirements of the CAA.[3] As a result of the removal of the problematic language from WAQSR Chapter 3, section 2(d), the improper exemptions from the emissions limitation contained within this provision will no longer be available to sources. EPA's proposed approval is also consistent with CAA section 110(l) because approval will not interfere with any applicable requirement of the CAA. Specifically, removal of the exemptions will not relax the existing emission limitation in the SIP and will in fact be more protective. Furthermore, this revision will render the revised emissions limitation consistent with the requirements of the CAA for SIP provisions by making it continuously applicable and more enforceable. Therefore, we are proposing to approve the removal of this language from the provision.[4]

Wyoming also added language to WAQSR Chapter 3, section 2(d) clarifying that the provision applies to both stationary and portable diesel engines. EPA finds no issue with this clarifying language and therefore proposes to approve this change as well.

IV. EPA's Proposed Action

We are proposing to approve the revisions to WAQSR Chapter 3, section 2(d) of the Wyoming SIP, as reflected in the State's February 10, 2014 submission.

V. Statutory and Executive Orders Review

Under the CAA, 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 choices, provided that they meet the criteria of the CAA. Accordingly, this proposed action merely proposes to approve state law as meeting federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, this proposed 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 USC 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 USC 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 USC 272 note) because application of those requirements would be inconsistent with the CAA; 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).

In addition, this proposed rule does not have tribal implications as specified by Executive Order 13175 (65 FR 67249, November 9, 2000), because the SIP is not approved to apply in Indian country located in the state, and EPA notes that it will not impose substantial direct costs on tribal governments or preempt tribal law.

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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: June 24, 2014.

Shaun L. McGrath,

Regional Administrator.

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1.  The Petition is available to view in the docket for this action.

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2.  Id. at 74.

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3.  For a more in-depth discussion on the inadequacy of WAQSR Chapter 3, section 2(d), see our proposed SIP call at 78 FR 12533, February 22, 2013.

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4.  We note that if we finalize our proposed approval of this revision to the Wyoming SIP, it will have the effect of mooting our proposed SIP call regarding this provision.

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[FR Doc. 2014-16740 Filed 7-15-14; 8:45 am]