Approval and Promulgation of Air Quality Implementation Plans; State of Wyoming; Sheridan PM10

SUMMARY

The Environmental Protection Agency (EPA) is proposing to fully approve the Limited Maintenance Plan (LMP), submitted by the State of Wyoming to the EPA on June 2, 2017, for the Sheridan moderate PM<INF>10</INF> nonattainment area (Sheridan NAA) and concurrently redesignate the Sheridan NAA to attainment of the National Ambient Air Quality Standard (NAAQS) for particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM<INF>10</INF>). In order to approve the LMP and redesignation, the EPA is proposing to determine that the Sheridan NAA has attained the 1987 24-hour PM<INF>10</INF> NAAQS of 150 [micro]g/m\3\. This determination is based upon monitored air quality data for the PM<INF>10</INF> NAAQS during the years 2014-2016. Additionally, the EPA is proposing to approve the Sheridan LMP as meeting the appropriate transportation conformity requirements found in 40 CFR 93, subpart A.

 
CONTENT

Federal Register, Volume 83 Issue 19 (Monday, January 29, 2018)

Federal Register Volume 83, Number 19 (Monday, January 29, 2018)

Proposed Rules

Pages 4015-4022

From the Federal Register Online via the Government Publishing Office www.gpo.gov

FR Doc No: 2018-01493

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

EPA-R08-OAR-2017-0656; FRL-9972-67-Region 8

Approval and Promulgation of Air Quality Implementation Plans; State of Wyoming; Sheridan PM10 Nonattainment Area Limited Maintenance Plan and Redesignation Request

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to fully approve the Limited Maintenance Plan (LMP), submitted by the State of Wyoming to the EPA on June 2, 2017, for the Sheridan moderate PM10 nonattainment area (Sheridan NAA) and concurrently redesignate the Sheridan NAA to attainment of the National Ambient Air Quality Standard (NAAQS) for particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM10). In order to approve the LMP and redesignation, the EPA is proposing to determine that the Sheridan NAA has attained the 1987 24-hour PM10 NAAQS of 150 microg/m\3\. This determination is based upon monitored air quality data for the PM10 NAAQS during the years 2014-2016. Additionally, the EPA is proposing to approve the Sheridan LMP as meeting the appropriate transportation conformity requirements found in 40 CFR 93, subpart A.

DATES: Written comments must be received on or before February 28, 2018.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R08-

OAR-2017-0656 at http://www.regulations.gov. Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from www.regulations.gov. The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission (i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full the EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: James Hou, Air Program, U.S. Environmental Protection Agency (EPA), Region 8, Mail Code 8P-AR, 1595 Wynkoop Street, Denver, Colorado 80202-1129, (303) 312-6210, email protected.

SUPPLEMENTARY INFORMATION:

  1. General Information

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

    1. Submitting Confidential Business Information (CBI). Do not submit CBI to the EPA through http://www.regulations.gov or email. Clearly mark the part or all of the information that you claim to be CBI. For CBI information on a disk or CD ROM that you mail to the 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

      Page 4016

      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 volume, 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.

  2. Background of the Sheridan PM10 Nonattainment Area (Sheridan NAA)

    1. Description of the Sheridan Nonattainment Area

    The Sheridan NAA encompasses the City of Sheridan, Wyoming, and was designated nonattainment for the 1987 24-hour PM10 NAAQS and classified as moderate under sections 107(d)(4)(B), following enactment of the Clean Air Act (CAA) Amendments of 1990. See 56 FR 56694 (November 6, 1991). States containing initial moderate PM10 nonattainment areas were required to submit, by November 15, 1991, a moderate nonattainment area State Implementation Plan (SIP) that, among other requirements, implemented Reasonably Available Control Measures (RACM) by December 10, 1993, and demonstrated whether it was practicable to attain the PM10 NAAQS by December 31, 1994. See generally 57 FR 13498 (April 16, 1992); see also 57 FR 18070 (April 28, 1992).

    The State of Wyoming submitted an initial PM10 SIP to the EPA on August 28, 1989, and subsequently submitted eight additional submittals between 1989 and 1991. The State of Wyoming's SIP for the Sheridan moderate nonattainment area included, among other things: A comprehensive emissions inventory; RACM; a demonstration that attainment of the PM10 NAAQS would be achieved in Sheridan by December 31, 1994; Reasonable Further Progress (RFP) requirements; and control measures that satisfy the contingency measures requirement of section 172(c)(9) of the CAA.

  3. Requirements for Redesignation

    1. CAA Requirements for Redesignation of Nonattainment Areas

      Nonattainment areas can be redesignated to attainment after the area has measured air quality data showing it has attained the NAAQS and when certain planning requirements are met. Section 107(d)(3)(E) of the CAA, and the General Preamble to Title I provide the criteria for redesignation. See 57 FR 13498 (April 16, 1992). These criteria are further clarified in a policy and guidance memorandum from John Calcagni, Director, Air Quality Management Division, EPA Office of Air Quality Planning and Standards dated September 4, 1992, ``Procedures for Processing Requests to Redesignate Areas to Attainment.'' \1\ The criteria for redesignation are:

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      \1\ The ``Procedures for Processing Requests to Redesignate Areas to Attainment'' (Calcagni memo) outlines the criteria for redesignation. The Calcagni memo can be found at https://www.epa.gov/sites/production/files/2016-03/documents/calcagni_memo_-_procedures_for_processing_requests_to_redesignate_areas_to_attainment_090492.pdf.

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      (1) The Administrator has determined that the area has attained the applicable NAAQS;

      (2) The Administrator has fully approved the applicable SIP for the area under section 110(k) of the CAA;

      (3) The state containing the area has met all requirements applicable to the area under section 110 and part D of the CAA;

      (4) The Administrator has determined that the improvement in air quality is due to permanent and enforceable reductions in emissions; and

      (5) The Administrator has fully approved a maintenance plan for the area as meeting the requirements of section 175A of the CAA.

    2. The LMP Option for PM10 Nonattainment Areas

      On August 9, 2001, the EPA issued guidance on streamlined maintenance plan provisions for certain moderate PM10 nonattainment areas seeking redesignation to attainment (Memo from Lydia Wegman, Director, Air Quality Standards and Strategies Division, entitled ``Limited Maintenance Plan Option for Moderate PM10 Nonattainment Areas,'' (hereafter the LMP Option memo)).\2\ The LMP Option memo contains a statistical demonstration that areas meeting certain air quality criteria will, with a high degree of probability, maintain the standard 10 years into the future. Thus, the EPA has already provided the maintenance demonstration for areas meeting the criteria outlined in the LMP Option memo. It follows that future year emission inventories for these areas, and some of the standard analyses to determine transportation conformity with the SIP are no longer necessary.

      To qualify for the LMP Option, the area should have attained the 1987 24-hour PM10 NAAQS, the average annual PM10 design value for the area, based upon the most recent five years of air quality data at all monitors in the area, should be at or below 40 microg/m\3\, and the 24-hour design value should be at or below 98 microg/m\3\. The annual PM10 standard was effectively revoked on December 18, 2006 (71 FR 61143), and as such will not be discussed as a requirement for qualifying for the LMP option. In addition, the area should expect only limited growth in on-road motor vehicle PM10 emissions (including fugitive dust) and should have passed a motor vehicle regional emissions analysis test. The LMP Option memo also identifies core provisions that must be included in the LMP. These provisions include an attainment year emissions inventory, assurance of continued operation of an EPA-approved air quality monitoring network, and contingency provisions.

    3. Conformity Under the LMP Option

      The transportation conformity rule (40 CFR parts 51 and 93) and the general conformity rule (40 CFR parts 51 and 93) apply to nonattainment areas and maintenance areas covered by an approved maintenance plan. Under either conformity rule, an acceptable method of demonstrating that a federal action conforms to the applicable SIP is to demonstrate that expected emissions from the planned action are consistent with the emissions budget for the area.

      While the EPA's LMP Option does not exempt an area from the need to affirm conformity, it explains that the area may demonstrate conformity without submitting an emissions budget. Under the LMP Option, emissions budgets are treated as essentially not constraining for the length of the maintenance period because it is unreasonable to expect that the qualifying areas would experience

      Page 4017

      so much growth in that period that a violation of the PM10 NAAQS would result. For transportation conformity purposes, the EPA would conclude that emissions in these areas need not be capped for the maintenance period; and therefore, a regional emissions analysis would not be required. Similarly, federal actions subject to the general conformity rule could be considered to satisfy the ``budget test'' specified in 40 CFR 93.158(a)(5)(i)(A) for the same reasons that the budgets are essentially considered not limited.

  4. Review of the Wyoming State Submittal Addressing the Requirements for Redesignation and Limited Maintenance Plans

    1. Has the Sheridan NAA attained the applicable NAAQS?

      States must demonstrate that an area has attained the 24-hour PM10 NAAQS through analysis of ambient air quality data from an ambient air monitoring network representing peak PM10 concentrations. The data should be stored in the EPA Air Quality System (AQS) database. The EPA is proposing to determine that the Sheridan NAA has attained the PM10 NAAQS based on monitoring data from calendar years 2014-2016. The 24-hour standard is attained when the expected number of days with levels above 150 microg/m\3\ (averaged over a three-year period) is less than or equal to one. 40 CFR 50.6(a). Three consecutive years of air quality data are generally necessary to show attainment of the 24-hour and annual standards for PM10. See 40 CFR part 50, appendix K. A complete year of air quality data, as referred to in 40 CFR part 50, appendix K, is comprised of all four calendar quarters with each quarter containing data from at least 75 percent of the scheduled sampling days.

      The Sheridan NAA has two State and Local Air Monitoring Stations (SLAMS) monitors operated by the Wyoming Department of Environmental Quality (WDEQ). Table 1 summarizes the PM10 data collected from 2012-2016. The EPA deems the data collected from these monitors valid, and the data has been submitted by the WDEQ to be included in AQS.

      Table 1--Summary of Maximum 24-Hour PM10 Concentrations microg/m\3\ for Sheridan 2012-2016

      Based on data from Sheridan Police Station, AQS Identification Number 56-033-0002

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      Maximum 2nd Maximum

      concentration concentration Number of

      Year (microg/ (microg/ exceedances Monitoring site

      m\3\) m\3\)

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      1. 75 73 0 Police Station.

      2. 57 52 0 Police Station.

      3. 47 45 0 Police Station.

      4. 73 73 0 Police Station.

      5. 54 48 0 Police Station.

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      The PM10 concentrations reported at the Sheridan monitoring sites showed no measured exceedances of the 24-hour PM10 NAAQS, and as such, the EPA proposes to determine that the Sheridan Moderate NAA has attained the standard for the 24-hour PM10 NAAQS.

    2. Does the Sheridan NAA have a fully approved SIP under CAA section 110(k)?

      In order to qualify for redesignation, the SIP for the area must be fully approved under CAA section 110(k), and must satisfy all requirements that apply to the area. Section 107(d)(4)(B) of the CAA contains requirements and milestones for all initial moderate nonattainment area SIPs including: (1) Provisions to assure that RACM (including such reductions in emissions from existing sources in the area as may be obtained through the adoption, at a minimum, of Reasonably Available Control Technology--RACT) shall be implemented no later than December 10, 1993; (2) A demonstration (including air quality modeling) that the plan will provide for attainment as expeditiously as practicable by no later than December 31, 1994, or, where the state is seeking an extension of the attainment date under section 188(e), a demonstration that attainment by December 31, 1994, is impracticable and that the plan provides for attainment by the most expeditious alternative date practicable (CAA sections 189(a)(1)(A)); (3) Quantitative milestones which are to be achieved every three years and which demonstrate RFP toward attainment by December 31, 1994, (CAA sections 172(c)(2) and 189(c)); and (4) Contingency measures to be implemented if the area fails to make RFP or attain by its attainment deadline. These contingency measures are to take effect without further action by the State or the EPA. (CAA section 172(c)(9)).

      As stated above, on June 23, 1994, the EPA approved Sheridan's moderate area plan including RACM, an attainment demonstration, emissions inventory, quantitative milestones, and control and contingency measure requirements. As such, the area has a fully approved nonattainment area SIP under section 110(k) of the CAA.

    3. Has the State met all applicable requirements under section 110 and Part D of the CAA?

      Section 107(d)(3)(E) of the CAA requires that a state containing a nonattainment area must meet all applicable requirements under section 110 and Part D of the CAA for an area to be redesignated to attainment. The EPA interprets this to mean that the state must meet all requirements that applied to the area prior to, and at the time of, the submission of a complete redesignation request. The following is a summary of how Wyoming meets these requirements.

      (1) CAA Section 110 Requirements

      Section 110(a)(2) of the CAA contains general requirements for nonattainment plans. These requirements include, but are not limited to, submittal of a SIP that has been adopted by the state after reasonable notice and public hearing; provisions for establishment and operation of appropriate apparatus, methods, systems and procedures necessary to monitor ambient air quality; implementation of a permit program; provisions for Part C--Prevention of Significant Deterioration (PSD) and Part D--New Source Review (NSR) permit programs; criteria for stationary source emission control measures, monitoring and reporting, provisions for modeling; and provisions for public and local agency

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      participation. See the General Preamble for further explanation of these requirements. 57 FR 13498 (April 16, 1992).

      For purposes of redesignation, the EPA's review of the Wyoming SIP shows that the State has satisfied all requirements under section 110(a)(2) of the CAA. Further, in 40 CFR 52.2622, the EPA has approved Wyoming's plan for the attainment and maintenance of the national standards under section 110.

      (2) Part D Requirements

      Part D contains general requirements applicable to all areas designated nonattainment. The general requirements are followed by a series of subparts specific to each pollutant. All PM10 nonattainment areas must meet the general provisions of Subpart 1 and the specific PM10 provisions in Subpart 4, ``Additional Provisions for Particulate Matter Nonattainment Areas.'' The following paragraphs discuss these requirements as they apply to the Sheridan NAA.

      (3) Subpart 1, Section 172(c)

      Subpart 1, section 172(c) contains general requirements for nonattainment area plans. A thorough discussion of these requirements may be found in the General Preamble. See 57 FR 13538 (April 16, 1992). CAA section 172(c)(2) requires nonattainment plans to provide for RFP. Section 171(1) of the CAA defines RFP as ``such annual incremental reductions in emissions of the relevant air pollutant as are required by this part (part D of title I) or may reasonably be required by the Administrator for the purpose of ensuring attainment of the applicable national ambient air quality standard by the applicable date.'' Wyoming submitted their first quantitative milestone report on March 29, 1995. Since the EPA is proposing to determine that the Sheridan NAA is in attainment of the PM10 NAAQS, we believe that no further showing of RFP or quantitative milestones is necessary.

      (4) Section 172(c)(3)--Emissions Inventory Section

      Section 172(c)(3) of the CAA requires a comprehensive, accurate, current inventory of actual emissions from all sources in the Sheridan PM10 nonattainment area. Wyoming included an emissions inventory for the calendar year 2014 with its DATE? submittal of the LMP for the Sheridan NAA. Based on the inventory preparation plan for the PM10 2014 base year emissions inventory, which includes windblown dust sources, the 2014 base year emissions inventory is current, accurate and comprehensive; and therefore, meets the requirements of Section 172(c)(3) of the CAA.

      (5) Section 172(c)(5)--NSR

      The 1990 CAA Amendments contained revisions to the NSR program requirements for the construction and operation of new and modified major stationary sources located in nonattainment areas. The CAA requires states to amend their SIPS to reflect these revisions, but does not require submittal of this element along with the other SIP elements. The CAA established June 30, 1992, as the submittal date for the revised NSR programs (Section 189 of the CAA). In lieu of instituting NSR regulations for construction in the Sheridan NAA, the State of Wyoming chose to institute a construction ban on major sources for the Sheridan NAA, which was deemed to have satisfied the NSR requirements, and was approved into the Wyoming SIP on November 29, 1994 (59 FR 60931).

      (6) Section 172(c)(7)--Compliance With CAA Section 110(a)(2): Air Quality Monitoring Requirements

      Once an area is redesignated, the state must continue to operate an appropriate air monitoring network in accord with 40 CFR part 58 to verify attainment status of the area. The State of Wyoming and the City of Sheridan operate two PM10 SLAMS in the Sheridan NAA. Both monitoring sites meet EPA SLAMS network design and siting requirements set forth at 40 CFR part 58, appendices D and E. The Police Station monitor has been in continuous operation since 1985, while the second monitoring station has been moved several times since 1998, but is currently sited at the Meadowlark Elementary School. In Section 6.6 of the LMP that we are proposing to approve, the State commits to continued operation of the monitoring network.

      (7) Section 172(c)(9)--Contingency Measures

      The CAA requires that contingency measures take effect if the area fails to meet RFP requirements or fails to attain the NAAQS by the applicable attainment date. Since the Sheridan NAA attained the 1987 24-hour PM10 NAAQS by the applicable attainment date of December 31, 1994, contingency measures are no longer required under Section 172(c)(9) of the CAA. However, contingency provisions are required for maintenance plans under Section 175(a)(d). We describe the contingency provisions Wyoming provided in the Sheridan LMP below.

      (8) Part D Subpart 4

      Part D Subpart 4, Section 189(a), (c) and (e) requirements apply to any moderate nonattainment area before the area can be redesignated to attainment. The requirements which were applicable prior to the submission of the request to redesignate the area must be fully approved into the SIP before redesignating the area to attainment. These requirements include: (a) Provisions to assure that RACM was implemented by December 10, 1993; (b) Either a demonstration that the plan provided for attainment as expeditiously as practicable but not later than December 31, 1994, or a demonstration that attainment by that date was impracticable; (c) Quantitative milestones which were achieved every three years and which demonstrate RFP toward attainment by December 31, 1994; and (d) Provisions to assure that the control requirements applicable to major stationary sources of PM10 also apply to major stationary sources of PM10 precursors except where the Administrator determined that such sources do not contribute significantly to PM10 levels which exceed the NAAQS in the area. These provisions were fully approved into the SIP upon the EPA's approval of the PM10 moderate area plan for the Sheridan NAA on June 23, 1994 (See 59 FR 32370), and the EPA is proposing to approve the attainment demonstration, based on the maintenance demonstration submitted with the LMP, in this action.

    4. Has the state demonstrated that the air quality improvement is due to permanent and enforceable reductions?

      The state must be able to reasonably attribute the improvement in air quality to permanent and enforceable emission reductions. In making this showing, the state must demonstrate that air quality improvements are the result of actual enforceable emission reductions. This showing should consider emission rates, production capacities, and other related information. The analysis should assume that sources are operating at permitted levels (or historic peak levels) unless evidence is presented that such an assumption is unrealistic. Permanent and enforceable control measures in the Sheridan NAA SIP include RACM. Emission sources in the Sheridan NAA have been implementing RACM for at least 10 years. In the EPA's approval of the Sheridan attainment plan on June 23, 1994, the EPA acknowledged that the primary source category

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      contributing to the PM10 nonattainment problem in Sheridan was fugitive road dust. The State demonstrated that, by applying the control measure, the ''Sanding Winter Maintenance Plan'' (SWMP), to designated streets during the Winter season, Sheridan would effectively control fugitive road dust; and thus, be in attainment by December 31, 1994. The State has noted that there have been updates to the SWMP, that are congruent with the original SWMP. However, in the intervening years since the approval of the Sheridan NAA attainment plan, many of the roads which were unpaved, have now been paved, allowing for plowing of the roads as opposed to frequent sanding. In the instances where sanding is still applied, it is applied consistent with the 1994 SWMP, as noted in section 3.3 of the Sheridan LMP.

      Areas that qualify for the LMP will meet the NAAQS, even under worst case meteorological conditions. Under the LMP option, the maintenance demonstration is presumed to be satisfied if an area meets the qualifying criteria. Thus, by qualifying for the LMP, Wyoming has demonstrated that the air quality improvements in the Sheridan area are the result of permanent emission reductions and not a result of either economic trends or meteorology. A description of the LMP qualifying criteria and how the Sheridan area meets these criteria is provided in the following section.

    5. Does the area have a fully approved maintenance plan pursuant to Section 175A of the CAA?

      In this action, we are proposing to approve the Limited Maintenance Plan in accordance with the principles outlined in the LMP Option.

    6. Has the state demonstrated that the Sheridan NAA qualifies for the LMP Option?

      The LMP Option memo outlines the requirements for an area to qualify for the LMP Option. First, the area should be attaining the NAAQS. As stated above in Section IV.A., the EPA has determined that the Sheridan NAA is attaining the PM10 NAAQS, based upon 2014-2016 data, and has had no exceedances between the years 2008-2016.

      Second, the average design value (ADV) for the past five years of monitoring data (2012-2016) must be at or below the critical design value (CDV). The CDV is a margin of safety value and is the value at which an area has been determined to have a 1 in 10 probability of exceeding the NAAQS. The LMP Option memo provides two methods for review of monitoring data for the purpose of qualifying for the LMP option. The first method is a comparison of a site's ADV with the CDV of 98 microg/m\3\ for the 24-hour PM10 NAAQS. A second method that applies to the 24-hour PM10 NAAQS is the calculation of a site-specific CDV and a comparison of the site-

      specific CDV with the ADV for the past five years of monitoring data. Table 2 outlines the design values for the years 2012-2016, and presents the ADV.

      Table 2--Summary of 24-Hour PM10 Design Values (microg/m\3\) for Sheridan 2012-2016

      Based on data from Sheridan Police Station and Meadowlark Elementary, AQS Identification Number 56-033-0002 and

      56-033-1003

      ----------------------------------------------------------------------------------------------------------------

      Design value

      Design value years (microg/ Monitoring site

      m\3\)

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      2012-2014.................................... 60 Police Station.

      2013-2015.................................... 57 Police Station.

      2014-2016.................................... 72 Police Station.

      2012-2014.................................... (*) Meadowlark Elementary.

      2013-2015.................................... 72 Meadowlark Elementary.

      2014-2016.................................... 72 Meadowlark Elementary.

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      Average DV based on highest DVs.............................. 68 microg/m\3\.

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      * The Meadowlark School monitor was installed on July 2012, and therefore missing the first two quarters in

      1. The 2012-2014 DV from the Police Station monitor was used to calculate the ADV for the NAA.

      The ADV for the 24-hour PM10 NAAQS for Sheridan, based on data from the collocated SLAMS monitors for the years 2012-2016, is 68 microg/m\3\. This value falls below the presumptive 24-hour CDV of 98 microg/m\3\. Therefore, Sheridan meets the design value criteria outlined in the LMP Option memo. For the 2012-2016 ADV calculations for PM10 in Sheridan, please see the supporting documents in the docket.\3\

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      \3\ See memo to file dated November 17, 2017 titled ``PM10 24-hour Design Concentration for Sheridan Wyoming.''

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      Third, the area must meet the motor vehicle regional emissions analysis test in attachment B of the LMP Option memo. Using the methodology outlined in the memo, based on monitoring data for the period 2014-2016, the EPA has determined that the Sheridan NAA passes the motor vehicle regional emissions analysis test. For the calculations used to determine that Sheridan has passed the motor vehicle regional analysis test, see the supporting documents in the docket.\4\

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      \4\ See memo to file dated December 4, 2017, title ``Sheridan Motor Vehicle Regional Emissions Analysis.''

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      The monitoring data for the period 2014-2016 shows that Sheridan has attained the NAAQS for PM10, the 24-hour ADV for Sheridan is less than the 24-hour PM10 CDV. Finally, the area has met the regional vehicle emissions analysis test. Thus, the Sheridan NAA qualifies for the LMP Option described in the LMP Option memo. The LMP Option memo also indicates that once a state selects the LMP Option and it is in effect, the state will be expected to determine, on an annual basis, that the LMP criteria are still being met. If the state determines that the LMP criteria are not being met, it should take action to reduce PM10 concentrations enough to requalify for the LMP. One possible approach the state could take is to implement contingency measures. Please see Section 6.3. for a description of contingency provisions submitted as part of the State's submittal.

    7. Does the state have an approved attainment emissions inventory which can be used to demonstrate attainment of the NAAQS?

      The state's approved attainment plan should include an emissions inventory (attainment inventory) which can be used to demonstrate attainment of the NAAQS. The inventory should represent emissions during the same five-year period associated with air quality data used to determine whether the area meets the applicability

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      requirements of the LMP Option. The state should review its inventory every three years to ensure emissions growth is incorporated in the attainment inventory if necessary. In this instance, Wyoming completed an attainment year inventory for the attainment year 2014. The EPA has reviewed the 2014 emissions inventory and determined that it is current, accurate and complete. The EPA has also reviewed monitoring data for the years 2012-2016, and determined that the 2014 emissions inventory is representative of the attainment year inventory since the NAAQS was not violated during 2014. In addition, the emissions inventory submitted with the LMP for the calendar year 2014 is representative of the level of emissions during the time period used to calculate the average design value since 2014 is included in the five-

      year period used to calculate the design value (2012-2016). As stated above in Section IV.C.4., the 2014 emissions inventory meets the requirements of Section 172(c)(3) of the CAA, and the requirements for emissions inventory in Table 3.1 of the EPA document entitled PM10 Emission Inventory Requirements, Final Report.

    8. Does the LMP include an assurance of continued operation of an appropriate EPA-approved air quality monitoring network, in accordance with 40 CFR Part 58?

      A PM10 monitoring network was established in the Sheridan NAA in 1984. Since that time, the Police Station monitor has been in continuous operation, while the neighborhood monitor has been moved several times since 1998. The neighborhood monitor is currently sited at the Meadowlark Elementary School. The monitoring network was developed and has been maintained in accordance with federal siting and design criteria in 40 CFR part 58, Appendices D and E and in consultation with EPA Region 8. Currently, there are two PM10/PM2.5 SLAMS/National Air Monitoring Stations (NAMS) monitors in the Sheridan NAA. In Section 6.6 of the Sheridan LMP, Wyoming states that it will continue to operate its monitoring network to meet EPA requirements.

  5. Does the plan meet the CAA requirements for contingency provisions for maintenance plans?

    Section 175A of the CAA states that a maintenance plan must include contingency provisions, as necessary, to promptly correct any violation of the NAAQS which may occur after redesignation of the area to attainment. As explained in the LMP Option memo, these contingency measures do not have to be fully adopted at the time of redesignation. As noted above, CAA section 175A requirements are distinct from CAA section 172(c)(9) contingency measures. Section 6.3 of the Sheridan Limited Maintenance Plan describes a process and timeline to identify and evaluate appropriate contingency measures in the event of a quality assured violation of the PM10 NAAQS. Upon notification of a PM10 exceedance, the AQD and local government staff in the Sheridan area will develop appropriate contingency measure(s) intended to prevent or correct a violation of the PM10 standard. Information about historical exceedances of the standard, the meteorological conditions related to the recent exceedance(s), and the most recent estimates of growth and emissions will be reviewed. The possibility that an exceptional event occurred will also be evaluated. The AQD will notify the EPA Region 8 within 45 days of any exceedance. Usually, upon notification to the Region, the AQD will indicate whether it believes that the event could be exceptional. If the event is considered eligible for data exclusion by the AQD, the AQD then provides official notification per the CFR (40 CFR 50.14) by flagging the affected data and providing a description with the quarterly data uploaded to AQS (90 days after the end of the quarter in which the event took place). Additionally, under the 2016 revisions to the Treatment of Data Influenced by Exceptional Events Rule (81 FR 68216), the AQD would confer with EPA Region 8 regarding whether the flagged event would meet the criteria of a regulatory decision, and if so, a determination would be made on whether to move forward with producing a demonstration. This process will be completed within six months of the exceedance notification. If a violation of the PM10 NAAQS has occurred, a public hearing process at the State and local level will begin. Contingency measures will be adopted and fully implemented within one year of a PM10 NAAQS violation. Any State-

    enforceable measures will become part of the next revised maintenance plan, submitted to the EPA for approval.

    Potential contingency provisions identified in the Sheridan LMP include the following:

    Re-implementing the voluntary wood burning curtailment program.

    Re-implementing the wood burning public information campaign.

    Mandatory wood burning curtailment.

    Bans on all wood burning.

    Implementing nonattainment new source review regulations for the City of Sheridan.

    Re-establishing the construction ban on major stationary sources that had been removed from Wyoming's State Implementation Plan.

    Paving the remaining unpaved roads within the City of Sheridan.

    Other restrictions/regulations/action plans involving stationary sources based on the consideration of cost-effectiveness, PM10 emission reduction potential, economic and social considerations, or other factors that the State deems appropriate.

    Coordination with the Wyoming Department of Transportation/local transit agency regarding roadwork and transportation control measures.

    The current and proposed contingency provisions in Sheridan's LMP meet the requirements for contingency provisions as outlined in the LMP Option memo.

    1. Has the state met transportation conformity requirements?

    (1) Transportation Conformity

    Transportation conformity is required by section 176(c) of the CAA. Conformity to a SIP means that transportation activities will not produce new air quality violations, worsen existing violations, or delay timely attainment of the NAAQS (CAA section 176(c)(1)(B)). The EPA's conformity rule at 40 CFR part 93, subpart A requires that transportation plans, programs and projects conform to SIPs and establishes the criteria and procedures for determining whether or not they conform. To effectuate its purpose, the conformity rule requires a demonstration that emissions from the Regional Transportation Plan, if applicable, and the Transportation Improvement Program are consistent with the motor vehicle emission budget (MVEB) contained in the control strategy SIP revision or maintenance plan (40 CFR 93.101, 93.118, and 93.124). The EPA notes that a MVEB is typically defined as the level of mobile source emissions of a pollutant relied upon in the attainment or maintenance demonstration to attain or maintain compliance with the NAAQS in the nonattainment or maintenance area.\5\ MVEBs are, however, treated differently with respect to LMP areas.

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    \5\ Further information concerning the EPA's interpretations regarding MVEBs can be found in the preamble to the EPA's November 24, 1993, transportation conformity rule (see 58 FR 62193-62196).

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    We note that under our LMP Option memorandum, MVEBs are not required

    Page 4021

    to be identified in the maintenance plan. While the EPA's LMP Option memo does not exempt an area from the need to affirm conformity, it explains that the area may demonstrate transportation conformity without identifying and submitting a MVEB. The basis for this provision in the LMP Option memorandum is that it is unreasonable to expect that an LMP area will experience so much growth during the maintenance period that a violation of the PM10 NAAQS would result. Therefore, for transportation conformity purposes, the EPA has concluded that mobile source emissions in LMP areas need not be capped, with respect to a MVEB, for the maintenance period and a regional emissions analysis (40 CFR 93.118), for transportation conformity purposes, is also not required.

    However, since LMP areas are still maintenance areas, certain aspects of the EPA's transportation conformity rule will continue to be required for transportation projects located within the Sheridan PM10 maintenance area. Specifically, for conformity determinations, projects will have to demonstrate that they are fiscally constrained (40 CFR 93.108) and meet the criteria for consultation and timely implementation (as applicable) of Transportation Control Measures (40 CFR 93.112 and 40 CFR 93.113, respectively). In addition, projects located within the Sheridan PM10 LMP area will be required to be evaluated for potential PM10 hot-spot issues in order to satisfy the ``project level'' conformity determination requirements. As appropriate, a project may then need to address the applicable criteria for a PM10 hot-spot analysis as provided in 40 CFR 93.116 and 40 CFR 93.123.

    Finally, our proposed approval of the Sheridan PM10 LMP affects future PM10 project-level transportation conformity determinations as prepared by the Wyoming Department of Transportation in conjunction with the Federal Highway Administration and the Federal Transit Administration. See 40 CFR 93.100. As such, the EPA is proposing to approve the Sheridan LMP as meeting the appropriate transportation conformity requirements found in 40 CFR 93, subpart A.

    (2) General Conformity

    Federal actions, other than transportation conformity, that meet specific criteria need to be evaluated with respect to the requirements of Wyoming's general conformity rule.\6\ Wyoming's general conformity rule requirements are designed to ensure that emissions from a federal action will not cause or contribute to new violations of the NAAQS, exacerbate current violations, or delay timely attainment. However, as noted in our LMP Option memorandum, and similar to the above discussed transportation conformity provisions, federal actions subject to Wyoming's general conformity rule would be considered to satisfy the ``budget test,'' as specified in WAQSR Chapter 8, Section 3(c)(vii)(C) of the rule. As discussed above, the basis for this provision in the LMP Option memorandum is that it is unreasonable to expect that an LMP area will experience so much growth during the maintenance period that a violation of the PM10 NAAQS would result. Therefore, for purposes of general conformity, a general conformity PM10 emissions budget does not need to be identified in the maintenance plan, nor submitted, and the emissions from federal agency actions are essentially considered to not be limited.

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    \6\ Wyoming Air Quality Standards and Regulations (WAQSR), Chapter 8, Section 3, General Conformity (as approved by the EPA; 78 FR 49685, August 15, 2013.)

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  6. The EPA's Proposed Action

    For the reasons explained in Section IV, we are proposing to approve the LMP for the Sheridan NAA and the State's request to redesignate the Sheridan NAA from nonattainment to attainment for the 1987 24-hour PM10 NAAQS. Additionally, the EPA is proposing to determine that the Sheridan NAA has attained the NAAQS for PM10. This determination is based upon monitored air quality data for the PM10 NAAQS during the years 2014-2016. Lastly, the EPA is proposing to approve the Sheridan LMP as meeting the appropriate transportation conformity requirements found in 40 CFR 93, subpart A.

  7. Statutory and Executive Orders Review

    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, the EPA's role is to approve state choices, provided that they meet the criteria of the CAA. Accordingly, this proposed action merely approves state law as meeting federal requirements; this proposed action 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 Orders 12866 (58 FR 51735, Oct. 4, 1993);

    Is not expected to be an Executive Order 13771 regulatory action because this action is not significant 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 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 CAA; and

    Does not provide the 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 the 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).

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    List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by reference, Intergovernmental relations, Particulate matter, Reporting and recordkeeping requirements.

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

    January 22, 2018.

    Douglas H. Benevento,

    Regional Administrator, Region 8.

    FR Doc. 2018-01493 Filed 1-26-18; 8:45 am

    BILLING CODE 6560-50-P