Approval and Promulgation of Air Quality Implementation Plans; State of Colorado Second Ten-Year PM10

Federal Register, Volume 78 Issue 230 (Friday, November 29, 2013)

Federal Register Volume 78, Number 230 (Friday, November 29, 2013)

Proposed Rules

Pages 71550-71554

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

FR Doc No: 2013-28652

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

EPA-R08-OAR-2011-0833; FRL-9903-25-Region-8

Approval and Promulgation of Air Quality Implementation Plans; State of Colorado Second Ten-Year PM10 Maintenance Plan for Telluride

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing to approve State Implementation Plan (SIP) revisions submitted by the State of Colorado. On March 31, 2010, the Governor of Colorado's designee submitted to EPA a revised maintenance plan for the Telluride area for the 24-hour National Ambient Air Quality Standards (NAAQS) for particulate matter with an aerodynamic diameter less than or equal to 10 microns (PM10), which was adopted on November 19, 2009. As required by Clean Air Act (CAA) section 175A(b), this revised maintenance plan addresses maintenance of the PM10 standard for a second 10-year period beyond the area's original redesignation to attainment for the PM10 NAAQS. In addition, EPA is proposing to approve the revised maintenance plan's 2021 transportation conformity motor vehicle emissions budget for PM10. Also, we are proposing to exclude from use in determining that Telluride continues to attain the PM10 NAAQS exceedances of the PM10 NAAQS that were recorded at the Telluride PM10 monitor on April 5, 2010 and April 16, 2013, because they meet the criteria for exceptional events caused by high wind natural events. This action is being taken under sections 110 and 175A of the CAA.

DATES: Written comments must be received on or before December 30, 2013.

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

OAR-2011-0833, by one of the following methods:

http://www.regulations.gov. Follow the on-line instructions for submitting comments.

Email: ostigaard.crystal@epa.gov.

Fax: (303) 312-6064 (please alert the individual listed in the FOR FURTHER INFORMATION CONTACT if you are faxing comments).

Mail: Carl Daly, Director, Air Program, U.S. Environmental Protection Agency (EPA), Region 8, Mailcode 8P-AR, 1595 Wynkoop Street, Denver, Colorado 80202-1129.

Hand Delivery: Carl Daly, Director, Air Program, U.S. Environmental Protection Agency (EPA), Region 8, Mailcode 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-

2011-0833. EPA's policy is that all comments received will be included in the public docket without change and may be made available online at http://www.regulations.gov, 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 http://www.regulations.gov or email. The http://www.regulations.gov 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 http://www.regulations.gov, your email address will be automatically captured and included as part of the comment 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 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 http://www.regulations.gov 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 http://www.regulations.gov or in hard copy at the Air Program, U.S. Environmental Protection Agency (EPA), Region 8, Mailcode 8P-AR, 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.

FOR FURTHER INFORMATION CONTACT: Crystal Ostigaard, Air Program, U.S. Environmental Protection Agency, Region 8, Mailcode 8P-AR, 1595 Wynkoop Street, Denver, Colorado 80202-1129, (303) 312-6602, ostigaard.crystal@epa.gov.

SUPPLEMENTARY INFORMATION:

Definitions

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 initials APCD mean or refer to the Colorado Air Pollution Control Division.

(iii) The initials AQCC mean or refer to the Colorado Air Quality Control Commission.

(iv) The initials AQS mean or refer to the EPA Air Quality System database.

(v) The words Colorado and State mean or refer to the State of Colorado.

(vi) The initials CDOT mean or refer to the Colorado Department of Transportation.

(vii) The initials CDPHE mean or refer to the Colorado Department of Public Health and Environment.

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

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(ix) The initials MVEB mean or refer to motor vehicle emissions budget.

(x) The initials NAAQS mean or refer to National Ambient Air Quality Standard.

(xi) The initials PM10 mean or refer to particulate matter with an aerodynamic diameter of less than or equal to 10 micrometers (coarse particulate matter).

(xii) The initials RTP mean or refer to the Regional Transportation Plan.

(xiii) The initials SIP mean or refer to State Implementation Plan.

(xiv) The initials TIP mean or refer to the Transportation Improvement Program.

(xv) The initials TSD mean or refer to technical support document.

Table of Contents

1. General Information

2. Background

3. What was the State's process?

4. EPA's Evaluation of the Revised Telluride PM10 Maintenance Plan

5. Proposed Action

6. Statutory and Executive Orders Review

1. General Information

   1. Submitting CBI. Do not submit CBI to 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 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:

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

   2. 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.

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

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

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

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

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

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

2. Background

   The Telluride area was designated nonattainment for PM10 and classified as moderate by operation of law upon enactment of the CAA Amendments of 1990. See 56 FR 56694, 56705, 56736 (November 6, 1991). EPA partially/conditionally approved Colorado's nonattainment area SIP for the Telluride PM10 nonattainment area on September 19, 1994 (59 FR 47807) and fully approved the SIP on October 4, 1996 (61 FR 51784). On May 10, 2000, the Governor of Colorado submitted a request to EPA to redesignate the Telluride moderate PM10 nonattainment area to attainment for the 1987 24-hour PM10 NAAQS. Along with this request, the State submitted a maintenance plan, which demonstrated that the area was expected to remain in attainment of the 24-hour PM10 NAAQS through 2012. EPA approved the Telluride maintenance plan and redesignation to attainment on June 15, 2001 (66 FR 32556).

   Eight years after an area is redesignated to attainment, CAA section 175A(b) requires the state to submit a subsequent maintenance plan to EPA, covering a second 10-year period.\1\ This second 10-year maintenance plan must demonstrate continued maintenance of the applicable NAAQS during this second 10-year period. To fulfill this requirement of the Act, the Governor of Colorado's designee submitted the second 10-year update of the PM10 maintenance plan to EPA on March 31, 2010 (hereafter; ``revised Telluride PM10 Maintenance Plan'').

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   \1\ In this case, the initial maintenance period described in CAA section 175A(a) was required to extend for at least 10 years after the redesignation to attainment, which was effective on August 14, 2001. See 66 FR 32556. So the first maintenance plan was required to show maintenance at least through 2011. CAA section 175A(b) requires that the second 10-year maintenance plan maintain the NAAQS for ``10 years after the expiration of the 10-year period referred to in section 175A(a).'' Thus, for the Telluride area, the second 10-year period ends in 2021.

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   As described in 40 CFR 50.6, the level of the national primary and secondary 24-hour ambient air quality standards for PM10 is 150 micrograms per cubic meter (mug/m\3\). An area attains the 24-

   hour PM10 standard when the expected number of days per calendar year with a 24-hour concentration in excess of the standard (referred to herein as ``exceedance''), as determined in accordance with 40 CFR part 50, appendix K, is equal to or less than one, averaged over a three-year period.\2\ See 40 CFR 50.6 and 40 CFR part 50, appendix K.

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   \2\ An exceedance is defined as a daily value that is above the level of the 24-hour standard, 150 microg/m\3\, after rounding to the nearest 10 microg/m\3\ (i.e., values ending in five or greater are to be rounded up). Thus, a recorded value of 154 microg/m\3\ would not be an exceedance since it would be rounded to 150 microg/m\3\; whereas, a recorded value of 155 microg/m\3\ would be an exceedance since it would be rounded to 160 microg/m\3\. See 40 CFR part 50, appendix K, section 1.0.

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   Table 1 below shows the maximum monitored 24-hour PM10 values for the Telluride PM10 maintenance area for 2004 through 2012, excluding one value that the State flagged as being caused by an exceptional event. The table reflects that the values for the Telluride area were well below the 24-hour PM10 NAAQS standard of 150 mug/m\3\. However, on April 5, 2010, the area experienced an exceedance measured at 354 mug/m\3\. The State flagged this value as a high wind exceptional event in EPA's Air Quality System (AQS), which is EPA's repository for ambient air quality data.

   40 CFR 50.1(j) defines an exceptional event as an event which affects air quality, is not reasonably controllable or preventable, is an event caused by human activity that is unlikely to recur at a particular location or a natural event, and is determined by the Administrator in accordance with 40 CFR 50.14 to be an exceptional event. Exceptional events do not include stagnation of air masses or meteorological inversions, meteorological events involving high temperatures or lack of precipitation, or air pollution relating to source noncompliance. 40 CFR 5.14(b) states that EPA shall exclude data from use in determinations of exceedances and NAAQS violations where a state demonstrates to EPA's satisfaction that an exceptional event caused a specific air pollution concentration in excess of one or more NAAQS at a particular air quality monitoring location and otherwise satisfies the requirements of section 50.14.

   The State submitted an exceptional event package on June 28, 2013 requesting EPA's concurrence on the flag for the April 5, 2010 exceedance. EPA completed its review of the exceptional events package for Telluride's 2010 exceedance and concurred on the flag on August 21,

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   2013 because the State successfully demonstrated that the exceedance on April 5, 2010 was caused by a natural high wind exceptional event due to blowing desert dust from upwind natural desert areas of Arizona, Utah, and southwest Colorado into the Telluride area.\3\ Thus, we are proposing to exclude from use in determining that Telluride continues to attain the 24- hour PM10 NAAQS the exceedance of the 24-

   hour PM10 NAAQS that was recorded at the Telluride PM10 monitor on April 5, 2010. See 40 CFR 50.14(b) and (c)(2)(ii). With the exclusion of this data point, the highest value in 2010 is 133 mug/m\3\, which is well below the 24-hour PM10 NAAQS standard.

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   \3\ Copies of the State's June 28, 2013 exceptional events package and our concurrence documents are included in the docket for this action.

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   Additionally, EPA reviewed 2013 data from AQS (this data has not yet been quality assured by Colorado) and found a high wind exceptional event of 265 mug/m\3\ at the Telluride monitor on April 16, 2013. The State submitted the exceptional events package for this exceedance on October 3, 2013, and EPA concurred on the package on November 1, 2013, because the State successfully demonstrated that the exceedance on April 16, 2013 was caused by a natural high wind exceptional event blowing desert dust from upwind natural desert areas of Arizona, Utah, and southwest Colorado into the Telluride area.\4\ Thus, we are proposing to exclude from use in determining that Telluride continues to attain the 24-hour PM10 NAAQS the exceedance of the 24-

   hour PM10 NAAQS that was recorded at the Telluride PM10 monitor on April 16, 2013.

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   \4\ Copies of the State's October 3, 2013 exceptional events package and our concurrence documents are included in the docket for this action.

   Table 1--Telluride PM10 Maximum 24-Hour Values

   Based on Data from 333 West Colorado Avenue, AQS Identification Number

   08-113-0004

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   Maximum

   Value

   Year (mug/

   m\3\)

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   2004. 72

   2005. 70

   2006. 69

   2007. 77

   2008. 82

   2009. 130

   2010. 133

   2011. 68

   2012. 80

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   Table 2 below shows the estimated number of exceedances for the Telluride PM10 maintenance area for the three-year periods of 2004 through 2006, 2005 through 2007, 2006 through 2008, 2007 through 2009, 2008 through 2010, 2009 through 2011, and 2010 through 2012. To attain the standard, the three-year average number of expected exceedances (values greater than 150 mug/m\3\) must be less than or equal to one. The table reflects continuous attainment of the 24-hour PM10 NAAQS.

   Table 2--Telluride PM10 Estimated Exceedances

   Based on Data from 333 West Colorado Avenue, AQS Identification Number

   08-113-0004

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   3-Year

   estimated

   Design value period number of

   exceedances

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   2004--2006............................................. 0

   2005--2007............................................. 0

   2006--2008............................................. 0

   2007--2009............................................. 0

   2008--2010............................................. 0

   2009--2011............................................. 0

   2010--2012............................................. 0

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3. What was the State's process?

   Section 110(a)(2) of the CAA requires that a state provide reasonable notice and public hearing before adopting a SIP revision and submitting it to EPA.

   The Colorado Air Quality Control Commission (AQCC) held a public hearing for the revised Telluride PM10 Maintenance Plan on November 19, 2009. The AQCC approved and adopted the revised Telluride PM10 Maintenance Plan during the hearing. The Governor's designee submitted the revised plan to EPA on March 31, 2010.

   We have evaluated the revised maintenance plan and have determined that the State met the requirements for reasonable public notice and public hearing under section 110(a)(2) of the CAA. On September 30, 2010, by operation of law under CAA section 110(k)(1)(B), the revised maintenance plan was deemed to have met the minimum ``completeness'' criteria found in 40 CFR part 51, appendix V.

4. EPA's Evaluation of the Revised Telluride PM10 Maintenance Plan

   The following are the key elements of a Maintenance Plan for PM10: Emission Inventory, Maintenance Demonstration, Monitoring Network/Verification of Continued Attainment, Contingency Plan, and Transportation Conformity Requirements including the Motor Vehicle Emission Budget for PM10. Below, we describe our evaluation of these elements as they pertain to the revised Telluride PM10 Maintenance Plan.

   1. Emission Inventory

      The revised Telluride PM10 Maintenance Plan includes three inventories of daily PM10 emissions for the Telluride area, for years 2007, 2015, and 2021. The Air Pollution Control Division (APCD) developed these emission inventories using EPA-approved emissions modeling methods and updated transportation and demographics data. Each emission inventory is a list, by source category, of the air contaminants directly emitted into the Telluride PM10 maintenance area. A more detailed description of the 2007, 2015 and 2021 inventories and information on model assumptions and parameters for each source category are contained in the State's PM10 Maintenance Plan Technical Support Document (TSD). Included in both inventories are agriculture, highway vehicle exhaust, railroads, road dust, commercial cooking, construction, fuel combustion, non-road sources, structure fires, and woodburning. We find that Colorado has prepared adequate emission inventories for the area.

   2. Maintenance Demonstration

      The revised Telluride PM10 Maintenance Plan uses emission roll-forward modeling to demonstrate maintenance of the 24-

      hour PM10 NAAQS through 2021. Using the 2007 and 2021 emissions inventories, the State first determined the projected growth in PM10 emissions from the 2007 base year to the 2021 maintenance year. The State estimated that emissions would increase from 1,285 pounds per day in 2007 to 1,989 pounds per day in 2021. This represents an increase of 54.8 percent.

      The State then applied this percentage increase to the design day concentration of 82 mug/m\3\, which was the highest 24-hour maximum PM10 value recorded in the Telluride area from 2006-2008. This resulted in an estimated maximum 24-hour PM10 concentration in 2021 of 126.9 mug/m\3\. This is well below the 24-

      hour PM10 NAAQS of 150 mug/m\3\.

   3. Monitoring Network/Verification of Continued Attainment

      In the revised Telluride PM10 Maintenance Plan, the State commits to continue to operate an air quality monitoring network in accordance with 40 CFR part 58 to verify continued attainment of the 24-hour PM10 NAAQS. This includes the continued operation of a PM10 monitor in the Telluride area, which the State will rely on to track PM10 emissions in the maintenance

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      area. The State also commits to conduct an annual review of the air quality surveillance system in accordance with 40 CFR 58.20(d) to determine whether the system continues to meet the monitoring objectives presented in Appendix D of 40 CFR part 58. Additionally, the State commits to track and document PM10 mobile source parameters and new and modified stationary source permits. If these and the resulting emissions change significantly over time, the APCD will perform appropriate studies to determine: (1) whether additional and/or re-sited monitors are necessary; and (2) whether mobile and stationary source emissions projections are on target.

      Based on the above, we are proposing approval of these commitments as satisfying the relevant requirements.

   4. Contingency Plan

      Section 175A(d) of the CAA requires that a maintenance plan include contingency provisions to promptly correct any violation of the NAAQS that occurs after redesignation of an area. To meet this requirement the State has identified appropriate contingency measures along with a schedule for the development and implementation of such measures.

      As stated in the revised Telluride PM10 Maintenance Plan, the contingency measures will be triggered by a violation of the 24-hour PM10 NAAQS. However, the maintenance plan notes that an exceedance of the 24-hour PM10 NAAQS may initiate a voluntary, local process by the Town of Telluride, the Town of Mountain Village, San Miguel County and the APCD to identify and evaluate potential contingency measures.

      The Town of Telluride, the Town of Mountain Village and San Miguel County in coordination with the APCD, AQCC, and the Colorado Department of Transportation (CDOT) will initiate a process to begin evaluating potential contingency measures no more than 60 days after notification from APCD that a violation of the 24-hour PM10 NAAQS has occurred. The AQCC will then hold a public hearing to consider the contingency measures recommended by the Town of Telluride, the Town of Mountain Village, San Miguel County, APCD and CDOT along with any other contingency measures the AQCC determines may be appropriate to effectively address the violation. The State commits to adopt and implement any necessary contingency measures within one year after a violation occurs.

      The State identifies the following as potential contingency measures in the revised Telluride PM10 maintenance plan: (1) Increased street sweeping requirements; (2) expanded, mandatory use of alternative de-icers; (3) more stringent street sand specifications; (4) road paving requirements; (5) woodburning restrictions; (6) re-

      establishing new source review permitting requirements for stationary sources; and (7) other emission control measures appropriate for the area based on consideration of cost effectiveness, PM10 emission reduction potential, economic and social considerations, or other factors.

      We find that the contingency measures provided in the revised Telluride PM10 Maintenance Plan are sufficient and meet the requirements of section 175A(d) of the CAA.

   5. Transportation Conformity Requirements: Motor Vehicle Emission Budget for PM10

      Transportation conformity is required by section 176(c) of the CAA. EPA's conformity rule at 40 CFR part 93 requires that transportation plans, programs, and projects conform to SIPs and establishes the criteria and procedures for determining whether or not they conform. 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. To effectuate its purpose, the conformity rule requires a demonstration that emissions from the Regional Transportation Plan (RTP) and the Transportation Improvement Program (TIP) are consistent with the motor vehicle emissions budget(s) (MVEB(s)) contained in a control strategy SIP revision or maintenance plan (40 CFR 93.101, 93.118, and 93.124). A MVEB is 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. Further information concerning EPA's interpretations regarding MVEBs can be found in the preamble to EPA's November 24, 1993, transportation conformity rule (see 58 FR 62193--62196).

      The revised Telluride PM10 Maintenance Plan contains a single MVEB of 1,108 lbs/day of PM10 for the year 2021, the maintenance year. Once the State submitted the revised plan with the 2021 MVEB to EPA for approval, 40 CFR 93.118 required that EPA determine whether the MVEB was adequate.

      Our criteria for determining whether a SIP's MVEB is adequate for conformity purposes are outlined in 40 CFR 93.118(e)(4), which was promulgated August 15, 1997 (see 62 FR 43780). Our process for determining adequacy is described in our July 1, 2004 Transportation Conformity Rule Amendments (see 69 FR 40004) and in relevant guidance.\5\ We used these resources in making our adequacy determination described below.

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      \5\ ``Companion Guidance for the July 1, 2004 Final Transportation Conformity Rule, Conformity Implementation in Multi-

      Jurisdictional Nonattainment and Maintenance Areas for Existing and New Air Quality Standards'' (EPA 420-B-04-012 July, 2004).

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      On November 22, 2010, EPA announced the availability of the revised Telluride PM10 Maintenance Plan, and the PM10 MVEB, on EPA's transportation conformity adequacy Web site. EPA solicited public comment on the MVEB, and the public comment period closed on December 22, 2010. We did not receive any comments. This information is available at EPA's conformity Web site: http://www.epa.gov/otaq/stateresources/transconf/currsips.htm#telluride.

      By letter to the Colorado Department of Public Health and Environment (CDPHE) dated March 21, 2011, EPA found that the revised Telluride PM10 Maintenance Plan and the 2021 PM10 MVEB were adequate for transportation conformity purposes.\6\ However, we noted in our letter that the revised Telluride PM10 Maintenance Plan did not discuss the PM10 MVEB for 2012 of 10,001 lbs/day from the original PM10 maintenance plan that EPA approved in 2001 (see 66 FR 32556, June 15, 2001).

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      \6\ In a Federal Register notice dated August 2, 2011, we notified the public of our finding (see 76 FR 46288). This adequacy determination became effective on August 17, 2011.

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      According to 40 CFR 93.118(e)(1), the EPA-approved 2012 PM10 MVEB must continue to be used for analysis years 2012 through 2020 (as long as such years are within the timeframe of the transportation plan), unless the State elects to submit a SIP revision to revise the 2012 PM10 MVEB and EPA approves the SIP revision. This is because the revised Telluride PM10 Maintenance Plan did not revise the previously-approved 2012 PM10 MVEB nor establish a new MVEB for 2012. Accordingly, the MVEB ``. . . for the most recent prior year . . .'' (i.e., 2012) from the original maintenance plan must continue to be used (see 40 CFR 93.118(b)(1)(ii) and (b)(2)(iv)).

      We note that there is a considerable difference between the 2021 and 2012 budgets--1,108 lbs/day versus 10,001 lbs/day. This is largely an artifact of changes in the methods, models, and

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      emission factors used to estimate mobile source emissions. The 2021 MVEB is consistent with the State's 2021 emissions inventory for vehicle exhaust and road dust, and, thus, is consistent with the State's maintenance demonstration for 2021.

      The discrepancy between the 2012 and 2021 MVEBs is not a significant issue for several reasons. As a practical matter, the 2021 MVEB of 1,108 lbs/day of PM10 would be controlling for any conformity determination involving the relevant years because conformity would have to be shown to both the 2012 MVEB and the 2021 MVEB. Also, for any maintenance plan, like the revised Telluride PM10 Maintenance Plan, that only establishes a MVEB for the last year of the maintenance plan, 40 CFR 93.118(b)(2)(i) requires that the demonstration of consistency with the budget be accompanied by a qualitative finding that there are no factors that would cause or contribute to a new violation or exacerbate an existing violation in the years before the last year of the maintenance plan. Therefore, when a conformity determination is prepared which assesses conformity for the years before 2021, the 2021 MVEB and the underlying assumptions supporting it would have to be considered. Finally, 40 CFR 93.110 requires the use of the latest planning assumptions in conformity determinations. Thus, the most current motor vehicle and road dust emission factors would need to be used, and we expect the analysis would show greatly reduced PM10 motor vehicle and road dust emissions from those calculated in the first maintenance plan. In view of the above, EPA is proposing to approve the 2021 PM10 MVEB of 1,108 lbs/day.

5. Proposed Action

   We are proposing to approve the revised Telluride PM10 Maintenance Plan that was submitted to us on March 31, 2010. We are proposing to approve the revised maintenance plan because it demonstrates maintenance through 2021 as required by CAA section 175A(b), retains the control measures from the initial PM10 maintenance plan that EPA approved in June of 2001, and meets other CAA requirements for a section 175A maintenance plan. We are proposing to exclude from use in determining that Telluride continues to attain the 24-hour PM10 NAAQS exceedances of the 24-hour PM10 NAAQS that were recorded at the Telluride PM10 monitor on April 5, 2010 and April 16, 2013 because they meet the criteria for exceptional events caused by high wind natural events. We are also proposing to approve the revised maintenance plan's 2021 transportation conformity MVEB for PM10 of 1,108 lbs/day.

6. Statutory and Executive Orders Review

   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 choices, provided that they meet the criteria of the Clean Air Act. This proposed action merely proposes to approve state law as meeting Federal requirements and does not propose to 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 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).

   In addition, this proposed action does not have tribal implications as specified by Executive Order 13175 (65 FR 67249, November 9, 2000), because the SIP would not be 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.

   List of Subjects in 40 CFR Part 52

   Environmental protection, Air pollution control, PM10, Incorporation by reference, Intergovernmental relations, Particulate matter, Reporting and recordkeeping requirements.

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

   Dated: November 18, 2013.

   Howard M. Cantor,

   Acting Regional Administrator, Region 8.

   FR Doc. 2013-28652 Filed 11-27-13; 8:45 am

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