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Proposed Rule

Air Quality Implementation Plans; Kentucky; Attainment Plan for the Kentucky Portion of the Huntington-Ashland 1997 Annual PM2.

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ACTION:

Proposed rule.

SUMMARY:

EPA is proposing to approve a state implementation plan (SIP) revision submitted by the Commonwealth of Kentucky, through the Kentucky Energy and Environment Cabinet, Division for Air Quality (DAQ), to EPA on December 3, 2008, for the purpose of providing for attainment of the 1997 fine particulate matter (PM2.5) national ambient air quality standards (NAAQS) in the Kentucky portion of the Huntington-Ashland, West Virginia-Kentucky-Ohio PM2.5 nonattainment area (hereafter referred to as the “Huntington-Ashland Area” or “Area”). The Huntington-Ashland Area is comprised of Boyd County and a portion of Lawrence County in Kentucky; Cabell and Wayne Counties and a portion of Mason County in West Virginia; and Lawrence and Scioto Counties and portions of Adams and Gallia Counties in Ohio. The Kentucky plan (hereafter referred to as the “attainment plan”) pertains only to the Kentucky portion of the Huntington-Ashland Area. EPA is now proposing to approve Kentucky's submittal regarding reasonably available control technology (RACT) and reasonably available control measures (RACM); reasonable further progress (RFP); base-year and attainment-year emissions inventories; contingency measures; and, for transportation conformity purposes, an insignificance determination for PM2.5 and nitrogen oxides (NOX) for the mobile source contribution to ambient PM2.5 levels for the Commonwealth's portion of the Huntington-Ashland Area. This action is being taken in accordance with the Clean Air Act (CAA or Act) and the “Clean Air Fine Particle Implementation Rule,” hereafter referred to as the “PM2.5 Implementation Rule,” issued by EPA on April 25, 2007. The States of West Virginia and Ohio have provided separate SIP revisions with attainment plans for their portions for the Huntington-Ashland Area. EPA will act on those SIP revisions in rulemaking separate from today's rulemaking.

DATES:

Written comments must be received on or before February 29, 2012.

ADDRESSES:

Submit your comments, identified by Docket ID Number EPA-R04-OAR-2010-0255 by one of the following methods:

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

2. Email: benjamin.lynorae@epa.gov.

3. Fax: (404) 562-9019.

4. Mail: EPA-R04-OAR-2010-0255, Regulatory Development Section, Air Planning Branch, Air, Pesticides and Toxics Management Division, U.S. Environmental Protection Agency, Region 4, 61 Forsyth Street SW., Atlanta, Georgia 30303-8960.

5. Hand Delivery or Courier: Ms. Lynorae Benjamin, Chief, Regulatory Development Section, Air Planning Branch, Air, Pesticides and Toxics Management Division, U.S. Environmental Protection Agency, Region 4, 61 Forsyth Street SW., Atlanta, Georgia 30303-8960. Such deliveries are only accepted during the Regional Office's normal hours of operation. The Regional Office's official hours of business are Monday through Friday, 8:30 to 4:30, excluding Federal holidays.

Instructions: Direct your comments to Docket ID No. EPA-R04-OAR-2010-0255. EPA's policy is that all comments received will be included in the public docket without change and may be made available online at 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 through www.regulations.gov or email, information that you consider to be CBI or otherwise protected. The 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 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 information about EPA's public docket visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.

Docket: All documents in the electronic docket are listed in the www.regulations.gov index. Although listed in the index, some information is not publicly available, i.e., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available either electronically in www.regulations.gov or in hard copy at the Regulatory Development Section, Air Planning Branch, Air, Pesticides and Toxics Management Division, U.S. Environmental Protection Agency, Region 4, 61 Forsyth Street SW., Atlanta, Georgia 30303-8960. EPA requests that if at all possible, you contact the person listed in the FOR FURTHER INFORMATION CONTACT section to schedule your inspection. The Regional Office's official hours of business are Monday through Friday, 8:30 to 4:30, excluding Federal holidays.

FOR FURTHER INFORMATION CONTACT:

Joel Huey of the Regulatory Development Section, in the Air Planning Branch, Air, Pesticides and Toxics Management Division, U.S. Environmental Protection Agency, Region 4, 61 Forsyth Street SW., Atlanta, Georgia 30303-8960. Joel Huey may be reached by phone at (404) 562-9104, or via electronic mail at huey.joel@epa.gov

SUPPLEMENTARY INFORMATION:

Table of Contents

I. What action is EPA proposing to take?

II. What is the background for EPA's proposed action?

A. Designation History

B. Clean Air Fine Particle Implementation Rule

C. Attaining Data Determination and Finding of Attainment

III. What is included in Kentucky's attainment plan submittal?

IV. What is EPA's analysis of Kentucky's attainment plan submittal?

A. Attainment Demonstration

1. Pollutants Addressed

2. Emissions Inventory Requirements

3. Modeling

4. Reasonably Available Control Measures/Reasonably Available Control Technology (RACM/RACT)

5. Reasonable Further Progress

6. Contingency Measures

7. Attainment Date

B. Insignificance Determination for the Mobile Source Contribution to PM2.5 and NOX Emissions

V. Proposed Action

VI. Statutory and Executive Order Reviews

I. What action is EPA proposing to take?

EPA is proposing to approve Kentucky's SIP revision, submitted through the DAQ to EPA on December 3, 2008, for the purpose of demonstrating attainment of the 1997 Annual PM2.5 NAAQS for the Kentucky portion of the Huntington-Ashland Area. Kentucky's PM2.5 attainment plan includes an analysis of RACM/RACT, an RFP plan, base-year and attainment-year emissions inventories for the Area, contingency measures, and an insignificance determination for mobile PM2.5 and NOx emissions for transportation conformity purposes.

EPA has determined that Kentucky's PM2.5 attainment plan for the 1997 Annual PM2.5 NAAQS for its portion of the Huntington-Ashland Area meets applicable requirements of the CAA and the PM2.5 Implementation Rule. EPA is proposing to approve Kentucky's attainment plan for the Commonwealth's portion of the Huntington-Ashland Area, including the insignificance determination for PM2.5 and NOX for the mobile source contribution to ambient PM2.5 levels for the Commonwealth's portion of the Huntington-Ashland Area. EPA's analysis for this proposed action is discussed in Section IV of this proposed rulemaking.

II. What is the background for EPA's proposed action?

A. Designation History

On July 18, 1997 (62 FR 36852), EPA established the 1997 PM2.5 NAAQS as an annual standard of 15.0 micrograms per cubic meter (µg/m3), based on a 3-year average of annual mean PM2.5 concentrations, and a 24-hour (or daily) standard of 65 µg/m3, based on a 3-year average of the 98th percentile of 24-hour concentrations. EPA established the NAAQS based on significant evidence and numerous health studies demonstrating that serious health effects are associated with exposures to PM2.5.

Following promulgation of a new or revised NAAQS, EPA is required by the CAA to designate areas throughout the United States as attaining or not attaining the NAAQS; this designation process is described in section 107(d)(1) of the CAA. EPA and state air quality agencies initiated the monitoring process for the 1997 PM2.5 NAAQS in 1999 and established a complete set of air quality monitors by January 2001. On January 5, 2005, EPA promulgated initial air quality designations for the 1997 PM2.5 NAAQS (70 FR 944), which became effective on April 5, 2005, based on air quality monitoring data for calendar years 2001-2003.

On April 14, 2005, EPA promulgated a supplemental rule amending the Agency's initial designations (70 FR 19844) but retaining the original effective date of April 5, 2005. As a result of that supplemental rule, PM2.5 nonattainment designations are in effect for 39 areas, comprising 208 counties within 20 states (and the District of Columbia) nationwide, with a combined population of about 88 million. The Kentucky portion of the tri-state WV-KY-OH Huntington-Ashland Area, which is the subject of this proposed rulemaking, is included in the list of areas designated nonattainment for the 1997 PM2.5 NAAQS. As mentioned above, the Kentucky portion of the Huntington-Ashland Area consists of Boyd County in its entirety and a portion of Lawrence County, Kentucky.

On October 17, 2006, EPA strengthened the 24-hour PM2.5 NAAQS to 35 µg/m3 and retained the level of the Annual PM2.5 NAAQS at 15.0 µg/m3. See 71 FR 61144. On November 13, 2009, EPA designated areas as either attainment/unclassifiable, unclassifiable or nonattainment with respect to the revised 24-Hour PM2.5 NAAQS. See 74 FR 58688. Of relevance to the proposed rulemaking herein, EPA's November 2009 designation action clarified the designations for the 1997 PM2.5 NAAQS by relabeling the existing designation tables to specifically identify designations made for the 1997 Annual PM2.5 NAAQS and those made for the 1997 24-hour PM2.5 NAAQS (i.e., 65 µg/m3).

B. Clean Air Fine Particle Implementation Rule

As noted above, on April 25, 2007, EPA issued the PM2.5 Implementation Rule for the 1997 PM2.5 NAAQS (72 FR 20586). This rule describes the CAA framework and requirements for developing SIPs to achieve attainment in areas designated nonattainment for the 1997 PM2.5 NAAQS. Such attainment plans must include a demonstration that a nonattainment area will meet the applicable NAAQS within the timeframe provided in the statute. This demonstration must include modeling that is performed in accordance with 40 CFR 51.112 (Demonstration of adequacy) and Appendix W to part 51 (Guideline on Air Quality Models) and that is consistent with EPA modeling guidance. See 40 CFR 51.1007. The modeling demonstration should include supporting technical analyses and descriptions of all relevant adopted Federal, state, and local regulations and control measures that have been adopted in order to provide for attainment of the 1997 PM2.5 NAAQS by the proposed attainment date.

For the 1997 PM2.5 NAAQS, an attainment demonstration must show that a nonattainment area will attain the standards as expeditiously as practicable, but within five years of designation (i.e., by an attainment date of no later than April 5, 2010, based on air quality data for 2007 through 2009). If the area is not expected to meet the NAAQS by April 5, 2010, a state may request to extend the attainment date by one to five years based upon the severity of the nonattainment problem or the feasibility of implementing control measures in the specific area. CAA section 172(a)(2). For EPA to approve an extension of the attainment date beyond 2010, the state must provide an analysis that is consistent with the statutory criteria for an extension and that demonstrates that the attainment date is as expeditious as practicable for the area, given the existing facts and circumstances.

For each nonattainment area, the state (or each state of a multi-state area) must demonstrate that it has adopted all RACM, including all RACT, as needed to provide for attainment of the PM2.5 NAAQS in the area “as expeditiously as practicable.” The PM2.5 Implementation Rule provides guidance for making these RACM/RACT determinations. See discussion in section IV.A.4. below. Any measures that are necessary to meet these requirements that are not already federally promulgated or in an EPA-approved part of the SIP must be submitted as part of a state's attainment plan. Any state measures in the control strategy must meet the applicable statutory and regulatory requirements, and, in particular, must be enforceable.

The PM2.5 Implementation Rule also includes guidance on pollutants that states must address in their attainment plans. Section 302(g) of the CAA authorizes EPA to regulate criteria pollutants and their precursors. The main chemical precursors associated with fine particle formation are SO2, NOX, volatile organic compounds (VOCs), and ammonia. The effect of reducing emissions of precursor pollutants that contribute to PM2.5 concentrations varies by area, however, depending upon local PM2.5 composition, emission levels, and other area-specific factors. For this reason, the PM2.5 Implementation Rule recommends that states control the direct PM2.5 emissions and the precursor emissions that would be most effective for attaining the NAAQS within the specific area, based upon an appropriate technical demonstration.

The PM2.5 Implementation Rule defines direct PM2.5 emissions as “solid particles emitted directly from an air emissions source or activity, or gaseous emissions or liquid droplets from an air emissions source or activity which condense to form particulate matter at ambient temperatures. Direct PM2.5 emissions include elemental carbon, directly emitted organic carbon, directly emitted sulfate, directly emitted nitrate, and other inorganic particles (including but not limited to crustal material, metals, and sea salt).” 40 CFR 51.1000.

The PM2.5 Implementation Rule requires states to identify and evaluate sources of PM2.5 direct emissions and PM2.5 attainment plan precursors. 40 CFR 51.1002(c). The rule requires states to address SO2 as a PM2.5 attainment plan precursor and to evaluate SO2 for possible control measures in all PM2.5 nonattainment areas. States are also required to address and evaluate reasonable controls for NOX as a PM2.5 attainment plan precursor unless the state and EPA make a finding that NOX emissions from sources in the state do not significantly contribute to PM2.5 concentrations in the relevant nonattainment area.

Although current scientific information shows that certain VOC emissions are precursors to the formation of secondary organic aerosol, and significant progress has been made in understanding the role of gaseous organic material in the formation of organic PM, this relationship remains complex. Further research and technical tools are needed to better characterize emissions inventories for specific VOCs and to determine the extent of the contribution of specific VOCs to organic PM mass. Because of these factors, the PM2.5 Implementation Rule does not require states to address or evaluate controls for VOCs as PM2.5 attainment plan precursors unless the state or EPA makes a finding that VOC emissions from sources in the state significantly contribute to PM2.5 concentrations in the relevant nonattainment area.

The PM2.5 Implementation Rule describes the formation of particles related to ammonia emissions, which is a complex, nonlinear process. Though recent studies have improved our understanding of the role of ammonia in aerosol formation, further research is needed to better describe the relationship between ammonia emissions and particulate matter concentrations and the related impacts. Also, area-specific data is needed to evaluate the effectiveness of reducing ammonia emissions in reducing PM2.5 concentrations in different areas and to determine where ammonia decreases may increase the acidity of particles and precipitation. For these reasons, the PM2.5 Implementation Rule does not require states to address or evaluate controls for ammonia as PM2.5 attainment plan precursors unless the state or EPA makes a finding that ammonia emissions from sources in the state significantly contribute to PM2.5 concentrations in the relevant nonattainment area.

The presumptive inclusion of NOX and the presumptive exclusion of VOCs and ammonia as attainment plan precursors can be reversed based on an acceptable technical demonstration for a particular nonattainment area by the state or EPA. The state must demonstrate that, based on the sum of available technical and scientific information, it would be appropriate for a nonattainment area to reverse the presumptive approach for a particular precursor. Such a demonstration should include information from multiple sources, such as results of speciation data analyses, air-quality modeling studies, chemical-tracer studies, emissions inventories, or special intensive measurement studies to evaluate specific atmospheric chemistry in an area. See PM2.5 Implementation Rule, 72 FR 20596.

The PM2.5 Implementation Rule also provides guidance for the other elements of a state's attainment plan, including, but not limited to, emissions inventories, contingency measures, and motor-vehicle emissions budgets used for transportation conformity purposes. There are, however, three aspects of the preamble to the PM2.5 Implementation Rule for which EPA received petitions requesting reconsideration. The specific guidance elements identified by petitioners pertain to the presumption or advance determination that compliance with the requirements of the Clean Air Interstate Rule (CAIR) automatically satisfies the requirements for RACT or RACM for NOX or SO2 emissions from electric generating unit (EGU) sources participating in regional cap and trade programs (See PM2.5 Implementation Rule, section II.F.7.); the suggestion that the economic feasibility element of a RACT determination should include consideration of whether the cost of a measure is reasonable in light of the benefits (See PM2.5 Implementation Rule, section II.F.5.); and the policy of allowing certain emissions reductions from outside the nonattainment area to be credited as meeting the RFP requirement (See PM2.5 Implementation Rule, section II.G.5.). EPA has granted these petitions and intends to propose rulemaking to change these aspects of the PM2.5 Implementation Rule. However, EPA's evaluation of the attainment plan for the Huntington-Ashland Area is not impacted by its reconsideration of any of these aspects of the PM2.5 Implementation Rule because the plan does not rely upon them.

C. Attaining Data Determination and Finding of Attainment

On September 7, 2011, EPA determined that the Huntington-Ashland Area had attaining data for the 1997 Annual PM2.5 NAAQS. 76 FR 55542. That determination was based on quality-assured, quality controlled and certified ambient air monitoring data that shows the area met the 1997 Annual PM2.5 NAAQS. Furthermore, in accordance with CAA 179(c), EPA determined in the same notice that the Huntington-Ashland Area attained the 1997 Annual PM2.5 NAAQS by its applicable attainment date of April 5, 2010. This information is mentioned here in support of EPA's determination that Kentucky's attainment plan was sufficient to bring the Huntington-Ashland Area into attainment no later than the required attainment date of April 5, 2010.

III. What is included in Kentucky's attainment plan submittal?

Kentucky's PM2.5 attainment plan submittal covers the Kentucky portion of the Huntington-Ashland Annual PM2.5 nonattainment area, which is the only portion for which the Commonwealth has jurisdiction. Today's action regards only the Kentucky portion of the Huntington-Ashland Area. However, the modeling analysis provided with Kentucky's attainment plan documentation includes modeling results for the entire tri-state Area and the results of Ohio and West Virginia's demonstrations for their portions of the Area, for which the conclusions of attainment are consistent with that of Kentucky's.

In accordance with section 172(c) of the CAA and the PM2.5 Implementation Rule, the attainment plan submitted by the DAQ for the Kentucky portion of the Huntington-Ashland Area includes (1) emissions inventories for the plan's base year (2002) and attainment year (2009); (2) an attainment demonstration; and (3) an insignificance finding for the mobile source contribution of PM2.5 and NOX. The attainment demonstration includes: (a) technical analyses that locate, identify, and quantify sources of emissions contributing to violations of the 1997 Annual PM2.5 NAAQS; (b) analyses of future-year emissions reductions and air quality improvements expected to result from national and local programs; adopted emission reduction measures with schedules for implementation; and contingency measures required under section 172(c)(9) of the CAA. See 72 FR 20605.

To analyze future-year emission reductions and air quality improvements, Kentucky used regional modeling analyses developed through the Association for Southeastern Integrated Planning (ASIP). The ASIP was a collaborative modeling and technical analysis effort among the states of Kentucky, Alabama, Florida, Georgia, Mississippi, North Carolina, South Carolina, Tennessee, Virginia and West Virginia to develop a regional assessment of the controls needed to achieve attainment of the 1997 PM2.5 NAAQS and the 2006 8-hour ozone NAAQS. This regional modeling was performed in accordance with EPA's “Guidance on the Use of Models and Other Analyses for Demonstrating Attainment of Air Quality Goals for Ozone, PM2.5, and Regional Haze” (EPA-454/B-07-002, April 2007) (hereafter referred to as “EPA's Modeling Guidance”).

IV. What is EPA's analysis of Kentucky's attainment plan submittal?

A. Attainment Demonstration

Consistent with CAA requirements (see, e.g., section 172), and 40 CFR 51.1007, an attainment demonstration for a PM2.5 nonattainment area must include a showing that the area will attain the annual and 24-hour standards as expeditiously as practicable. The demonstration must also meet the requirements of 40 CFR 51.112 and Part 51, Appendix W, and include inventory data, modeling results, and emissions reduction analyses on which the state has based its projected attainment. In the case of the Huntington-Ashland Area, the Area has already attained the standard. Thus, EPA is now proposing to determine that the attainment demonstration submitted by the Commonwealth was sufficient, and EPA is taking action to approve individual components that are necessary for the continued attainment and maintenance of the Area.

1. Pollutants Addressed

As discussed in section II.B. above, the PM2.5 Implementation Rule requires states to identify and evaluate sources of PM2.5 direct emissions and PM2.5 attainment plan precursors. The rule provides that SO2 is a PM2.5 attainment plan precursor in all areas. The rule also sets forth the rebuttable presumptions that NOX is a PM2.5 attainment plan precursor in all areas and that ammonia and VOCs are not PM2.5 attainment plan precursors. Neither Kentucky nor the EPA has found reason to reverse these presumptions for the Huntington-Ashland Area. Accordingly, Kentucky's PM2.5 attainment plan evaluates emissions of direct PM2.5, SO2, and NOX in the Kentucky portion of the Huntington-Ashland Area.

2. Emissions Inventory Requirements

States are required under section 172(c)(3) of the CAA to develop comprehensive, accurate and current emissions inventories of all sources of the relevant pollutant or pollutants in the area. These inventories provide a detailed accounting of all emissions and emissions sources by precursor or pollutant. In addition, inventories are used in air quality modeling to demonstrate that attainment of the 1997 PM2.5 NAAQS is as expeditious as practicable and, if an attainment date extension beyond 2010 is needed, to support the need for such an extension. Emissions inventory guidance was provided in the April 1999 document, “Emissions Inventory Guidance for Implementation of Ozone and Particulate Matter NAAQS and Regional Haze Regulations,” (EPA-454/R-99-006), which was updated in November 2005 (EPA-454/R-05-001) (hereafter referred to as “EPA's Emissions Inventory Guidance”). Emissions reporting requirements were provided in the 2002 Consolidated Emissions Reporting Rule (CERR) (67 FR 39602). On December 17, 2008 (73 FR 76539), EPA promulgated the Air Emissions Reporting Requirements (AERR) to update emissions reporting requirements in the CERR and to harmonize, consolidate and simplify data reporting by states.

In accordance with the CERR and EPA's Emissions Inventory Guidance, the PM2.5 Implementation Rule requires states to submit inventory information on directly emitted PM2.5 and PM2.5 precursors and any additional inventory information needed to support an attainment demonstration and (where applicable) an RFP plan.

PM2.5 is comprised of filterable and condensable emissions. Condensable particulate matter (CPM) can comprise a significant percentage of direct PM2.5 emissions from certain sources and are required to be included in national emissions inventories based on emission factors. Test Methods 201A and 202 are available for source-specific measurement of condensable emissions. However, the PM2.5 Implementation Rule notes that there were issues raised by commenters related to availability and implementation of these test methods as well as uncertainties in existing data for condensable PM2.5. EPA established a transition period during which EPA could assess possible revisions to available test methods and to allow time for states to update emissions inventories as needed to address direct PM2.5, including condensable emissions. Because of the time required for this assessment, EPA recognized that states would be limited in how to effectively address CPM emissions and established a period of transition, up to January 1, 2011, during which state submissions for PM2.5 were not required to address CPM emissions. Amendments to these test methods were proposed on March 25, 2009 (74 FR 12969), and finalized on December 21, 2010 (75 FR 80118). The amendments to Method 201A added a particle-sizing device for PM2.5 sampling, and the amendments to Method 202 revised the sample collection and recovery procedures of the method to reduce the formation of reaction artifacts that could lead to inaccurate measurements of CPM emissions.

The period of transition for establishing emissions limits for condensable direct PM2.5 ended on January 1, 2011. PM2.5 submissions made during the transition period are not required to address CPM emissions, however, states must address the control of direct PM2.5 emissions, including condensable emissions, with any new action taken after January 1, 2011. Kentucky submitted the Huntington-Ashland Area attainment plan prior to January 1, 2011, and did not consider CPM in addressing the control of PM2.5 emissions.

In July 2008, EarthJustice filed a petition requesting reconsideration of EPA's transition period for CPM emissions provided in the PM2.5 Implementation Rule. In January 2009, EPA decided to allow states that have not previously addressed CPM to continue to exclude CPM for PSD permitting during the transition period. Today's action reflects a review of Kentucky's submittal based on current EPA guidance as described in the PM2.5 Implementation Rule.

The 172(c)(3) emissions inventory is developed by the incorporation of data from multiple sources. States were required to develop and submit to EPA a triennial emissions inventory according to the CERR for all source categories (i.e., point, area, nonroad mobile and on-road mobile). This inventory often forms the basis of data that are updated with more recent information and data that also is used in their attainment demonstration modeling inventory. Such was the case in the development of the 2002 emissions inventory that was submitted in the Commonwealth's attainment SIP for this Area. The 2002 emissions inventory was based on data developed with Visibility Improvement State and Tribal Association of the Southeast (VISTAS) contractors for the same ten states of the ASIP effort and submitted by the states to the 2002 National Emissions Inventory. Several iterations of the 2002 inventories were developed for the different emissions source categories resulting from revisions and updates to the data. This resulted in the use of version G2 of the updated data to represent the point sources' emissions. Data from many databases, studies and models (e.g., vehicle miles traveled, fuel programs, the NONROAD 2002 model data for commercial marine vessels, locomotives and Clean Air Market Division, etc.) resulted in the inventory submitted in this SIP. The data were developed according to EPA's Emissions Inventory Guidance and a quality assurance project plan that was developed through VISTAS and approved by EPA. EPA agrees that the process used to develop this inventory was adequate to meet the requirements of the CAA, e.g., CAA section 172(c)(3), and the implementing regulations.

Tables 1-5 below show the level of emissions in the Kentucky portion of the Huntington-Ashland Area for 2002 by pollutant, county, and emissions source category. The point, area, and nonroad values for Lawrence County in the December 8, 2008, submittal were for the entire county, not just the census block that EPA designated as nonattainment. On May 26, 2011, at the request of EPA, the Commonwealth submitted updated tables to include information on point source emissions from the designated census block and population based apportionment of the area and nonroad sectors to support the mobile source insignificance finding discussed further in Section IV.B. below. A copy of the May 26, 2011, clarification letter and updated tables can be found in the docket for this proposed action (EPA-R02-OAR-2010-0255) on the www.regulations.gov Web site. EPA is proposing to approve the emissions inventory for the Kentucky portion of the Huntington-Ashland Area as meeting the requirements of Section 172(c)(3) of the CAA.

Table 1—Base and Attainment Year VOC Inventory for the Kentucky Portion of the Huntington-Ashland Area

VOC (tpy)Boyd CountyLawrence CountyKY portion total
200220092002200920022009
Point308332599811931813378
Area78077537435711541132
Mobile9916134092691400882
Nonroad312256223271535527
Total516649031104101662705919

Table 2—Base and Attainment Year NOX Inventory for the Kentucky Portion of the Huntington-Ashland Area

NOX (tpy)Boyd CountyLawrence CountyKY portion total
200220092002200920022009
Point704672811712957302417513011
Area40468793127139
Mobile121377478552819981302
Nonroad3319310772666440453771
Total11618112081872770153034518223

Table 3—Base and Attainment Year SO2 Inventory for the Kentucky Portion of the Huntington-Ashland Area

SO2 (tpy)Boyd CountyLawrence CountyKY portion total
200220092002200920022009
Point97111043248874477395858558171
Area54257896102638680
Mobile5463048410
Nonroad4823808552567432
Total107891139649085478975987459293

Table 4—Base and Attainment Year PM2.5 Inventory for the Kentucky Portion of the Huntington-Ashland Area

PM2.5 (tpy)Boyd CountyLawrence CountyKY portion total
200220092002200920022009
Point1256125533541315911668
Area712748216219928967
Mobile211514103525
Nonroad1311213028161149
Total2120213959567027152809

Table 5—Base and Attainment Year Ammonia Inventory for the Kentucky Portion of the Huntington-Ashland Area

Ammonia (tpy)Boyd CountyLawrence CountyKY portion total
200220092002200920022009
Point3363783144367422
Area383828286666
Mobile445320266479
Nonroad000000
Total4184697998497567

EPA has reviewed Kentucky's emissions inventory and finds that it is adequate for the purposes of meeting section 172(c)(3) emissions inventory requirement. The emissions inventory is approvable because the emissions were developed consistent with the CAA, implementing regulations and EPA guidance for emissions inventories. Additional emissions inventory information, including summary tables for the Ohio and West Virginia portions of the Huntington-Ashland Area, are included in Appendix E of Kentucky's attainment SIP and are located in the docket for this proposed action (EPA-R02-OAR-2010-0255) on the www.regulations.gov Web site.

3. Modeling

The PM2.5 attainment demonstrations must include modeling that should be developed in accordance with EPA's Modeling Guidance. A brief description of the modeling used to support Kentucky's attainment demonstration follows. More detailed information can be found in Kentucky's December 3, 2010, SIP revision in the docket for this proposed action (EPA-R02-OAR-2010-0255) on the www.regulations.gov Web site.

Ambient PM2.5 typically includes both primary (directly emitted) PM2.5 and secondary PM2.5 (e.g., sulfates and nitrates formed by chemical reactions in the atmosphere). Some of the physicochemical processes leading to the formation of secondary PM2.5 may take hours or days, as may some of the removal processes. Thus, some sources of secondary PM2.5 may be sources outside of the nonattainment area. To model a sufficient geographic area to take these processes into account, Kentucky' regional modeling domain covered an area slightly greater than the geographical area of the VISTAS/ASIP states in this attainment demonstration.

Kentucky, through the ASIP and VISTAS, conducted an analysis of the major contributing components of PM2.5 in the Kentucky portion of the Huntington-Ashland Area. Specifically, organic carbon (OC) and sulfuric acid (SO4) account for the largest contributions. The majority of OC can be attributed to biogenic emissions and SO4 to emissions of SO2. SO2 emissions are primarily associated with the point source sector, accounting for approximately 98 percent of the SO2 emission in the Huntington-Ashland Area. Emissions sensitivity modeling for the Huntington-Ashland Area indicated that SO2 emissions reductions from EGUs in Kentucky, Tennessee, and West Virginia would have the greatest benefits for the Area. The VISTAS modeling also projects limited benefits to total PM2.5 emissions from reductions of NOX. The modeling performed by VISTAS showed that reductions of primary carbon from the mobile sector were more effective than reductions of either VOCs or NOX from mobile sources. EPA agrees with Kentucky's assertion that controlling SO2 from point sources is the most effective means of addressing attainment of the 1997 Annual PM2.5 NAAQS in the Huntington-Ashland Area.

Model Selection and Inputs

The ASIP performed modeling for ozone and PM2.5 for the 10 collaborating southeastern states, including Kentucky. The modeling analysis is a complex technical evaluation that began with selection of the modeling system. The ASIP and/or VISTAS used the following modeling system:

  • Meteorological Model: The Pennsylvania State University/National Center for Atmospheric Research Mesoscale Meteorological Model is a nonhydrostatic, prognostic meteorological model routinely used for urban- and regional-scale photochemical, ozone, PM2.5, and regional haze regulatory modeling studies.
  • Emissions Model: The Sparse Matrix Operator Kernel Emissions modeling system is an emissions modeling system that generates hourly gridded speciated emission inputs of mobile, non-road mobile, area, point, fire and biogenic emission sources for photochemical grid models.
  • Air Quality Model: The EPA's Models-3/Community Multiscale Air Quality (CMAQ) modeling system is a photochemical grid model capable of addressing ozone, PM, visibility and acid deposition at a regional scale. The photochemical model selected for this study was CMAQ version 4.5. It was modified through VISTAS with a module for Secondary Organics Aerosols in an open and transparent manner that was also subjected to outside peer review.

CMAQ modeling of regional haze in the VISTAS region for 2002 and 2009 was carried out on a grid of 12 × 12 kilometer cells that covers the ten VISTAS states and states adjacent to them. This grid is nested within a larger national CMAQ modeling grid of 36 × 36 kilometer grid cells that covers the continental United States, portions of Canada and Mexico, and portions of the Atlantic and Pacific Oceans along the east and west coasts. Selection of a representative period of meteorology is crucial for evaluating baseline air quality conditions and projecting future changes in air quality due to changes in emissions of visibility-impairing pollutants. VISTAS conducted an in-depth analysis which resulted in the selection of the entire calendar year of 2002 as the best period of meteorology available for conducting the CMAQ modeling. As noted above, the VISTAS and ASIP states modeling was developed consistent with EPA's Emissions Inventory Guidance and EPA's Modeling Guidance .

VISTAS examined the model performance of the regional modeling for the areas of interest before determining whether the CMAQ model results were suitable for use in the assessment of an attainment of the PM2.5 NAAQS and for use in the modeling assessment. The modeling assessment predicts future levels of emissions and visibility impairment used to support the 2009 PM2.5 control strategy. In keeping with the objective of the CMAQ modeling platform, the air quality model performance was evaluated using graphical and statistical assessments based on measured ozone, fine particles, and acid deposition from various monitoring networks and databases for the 2002 base year. A diverse set of statistical parameters from the EPA's Modeling Guidance was used to stress and examine the model and modeling inputs. Once the model performance of the 2002 base year was determined to be acceptable, the EPA model attainment test was used to assess whether attainment of the PM2.5 NAAQS would be achieved in 2009. The DAQ provided the appropriate supporting documentation for all required analyses used to determine Kentucky's control strategy. The technical analyses and modeling used to assess attainment in 2009 for the Area is consistent with the CAA, EPA's PM2.5 Implementation Rule and EPA's Modeling Guidance. EPA accepts the VISTAS and ASIP technical modeling to support the attainment SIP for the Area because the modeling system was chosen and simulated according to EPA's Modeling Guidance. For purposes of the Huntington-Ashland attainment demonstration, EPA agrees with the VISTAS model performance procedures and results, and that the CMAQ is an appropriate tool for the assessment of PM2.5 for the Kentucky attainment demonstration for this Area. Additional details on the ASIP and VISTAS modeling is included in the Kentucky SIP.

Modeling Results

The modeling results were used in a relative sense in concert with observed PM2.5 air quality data (i.e., taking the ratio of future to present model predicted air quality and multiplying it times an “ambient design value”). The ambient design value is an average of the three current design values (i.e., 2001, 2002, and 2003) that straddle the modeling base year (i.e., 2002). EPA recommends using the average of the three design value periods which include the baseline inventory year. This average design value best represents the baseline concentrations, while taking into account the variability of meteorology and emissions (over a five-year period). This EPA attainment test approach should reduce some of the uncertainty involved with using absolute model predictions alone. Using the model in a relative sense also reduces the effects of uneven model performance and possible major biases in predicting absolute concentrations of one or more components. The ratio of future to present model predicted air quality resulted in relative reduction factors (RRF). The multiplication of the RRF by an ambient design value from the base year (i.e., 2002) provided estimates of future design values to determine if monitors and areas with monitors in the nonattainment area will comply with the annual PM2.5 NAAQS.

EPA provided guidance to states and tribes for projecting PM2.5 concentrations using a “speciated modeled attainment test” (SMAT) (EPA-454/B-07-002, April 2007). Once modeling for a projection year and a base year are complete, RRFs are computed for each component of PM2.5 in the modeling domain. Modeling by Kentucky to assess attainment in the entire Huntington-Ashland Area used the following components of PM2.5: SO4, NO3, directly emitted organic particles, and directly emitted inorganic particles. Ammonia is treated as part of SO4 and NO3 molecules, and water is assumed to be present at a constant mass in both the base year and projection year. For each monitoring location, the RRF for a component is computed as the ratio of the projection year divided by the base year modeled concentration for a three-by-three array of modeled grid cells centered on the monitoring location.

Projection year component concentrations are estimated by multiplying the RRFs times a monitoring based base year component concentration, determined by applying measured speciation data to the monitored total PM2.5 design concentration. The sum of these estimated projection year component concentrations is the estimated projection year PM2.5 concentration. If future estimates of PM2.5 concentrations are less than the 1997 PM2.5 NAAQS, then the modeling indicates attainment of the standard.

PM2.5 includes a mixture of components that can behave independently from one another (e.g., primary vs. secondary particles) or that are related to one another in a complex way (e.g., different secondary particles). Thus, it is appropriate to consider the predicted future concentration of PM2.5 to be the sum of the predicted component concentrations. See 72 FR 20608. As recommended in EPA's Modeling Guidance, Kentucky divided PM2.5 into its major components and noted the future effects of already implemented strategies on each. The effect on PM2.5 was estimated as a sum of the effects on individual components. Future PM2.5 design values at specified monitoring sites were estimated by adding the future-year values of seven PM2.5 components. All future site-specific PM2.5 design values were below the concentration specified in the NAAQS; therefore, the Huntington-Ashland Area passed the SMAT evaluation.

EPA has also developed a software package called Modeled Attainment Test Software (MATS) which will spatially interpolate data, adjust the spatial fields based on model output gradients and multiply the fields by model calculated RRFs. EPA recommended that the Commonwealth provide MATS attainment test values for 2009 since the tool became available soon after Kentucky had drafted its attainment demonstration. The 2009 MATS values for the entire Huntington-Ashland Area also indicate attainment of the annual PM2.5 NAAQS in 2009. Table 7 illustrates the current (2002 DVC) and future (2009 DVF) annual design values for 2009 for the monitors in the nonattainment area.

Table 7—2002 Current and 2009 Predicted Annual PM2.5 Design Values (μg/m3)

Site No.StateCounty2002 Annual DVC2009 Annual DVF
21-019-0017KYBoyd14.912.6
39-087-0010OHLawrence15.713.7
39-145-0013OHScioto17.114.7
54-011-0006WVCabell16.514.4

Additional Analysis

Kentucky provided supplemental analysis to further support results from the modeled attainment tests. As a first step, Kentucky noted that the modeled attainment tests supported a conclusion that the proposed strategy will meet the air quality goals by the attainment year. As noted in section 7 of EPA's Modeling Guidance, corroboratory analyses should be used to help assess whether a simulated control strategy is sufficient to meet the NAAQS. One of the metrics identified in the guidance is the calculations of the percent change in the number of grid cells greater than or equal to 15.0 µg/m3 in the nonattainment area. For Kentucky's analysis, cell counts of modeling data were tallied for both the 2002 baseline and 2009 attainment year modeling runs for a subset of the highest days from the base year and which coincide with the 29 days used in the model performance evaluation and modeling results discussed previously. The analysis indicates a 10 percent increase in the number of cells representing days with concentrations below 15.0 μg/m3.

Kentucky conducted an additional unmonitored area analysis to ensure that a control strategy leads to reductions in PM2.5 at other locations which could have baseline (and future) design values exceeding the NAAQS were a monitor deployed there. Consistent with EPA's Modeling Guidance, the ASIP determined the 2002 current year and 2009 projected PM2.5 design values in the Huntington-Ashland Area using the 2002 typical and 2009 BaseG4 CMAQ 12 km modeling results. Appendix L of the Commonwealth's submittal contains maps which illustrate that the MATS projections for the unmonitored areas in Kentucky and the entire Huntington-Ashland Area will be below the PM2.5 NAAQS by 2009.

EPA Analysis

Kentucky's PM2.5 attainment demonstration submittal covers only the portion of the Huntington-Ashland Area for which Commonwealth has jurisdiction (Boyd County and a portion of Lawrence County). However, the modeling results for the West Virginia and Ohio portions of the Area reach conclusions of attainment which are consistent with that of Kentucky. The technical analyses and modeling to assess attainment of the entire nonattainment Area were developed consistent with EPA's Modeling Guidance. The modeling system was chosen and simulated to develop a model performance evaluation of the nonattainment area to provide the necessary assurances and results that an assessment of future controls for attainment is merited. Application of the EPA modeled attainment test and the MATS indicated future design values that are less than 15.0 μg/m3 and consistent with attainment of the 1997 Annual PM2.5 NAAQS. The additional analyses based on other regional modeling studies, including EPA and the Midwest RPO, support the modeling results developed by the ASIP and Kentucky. Finally, the area's status as having attained the standard further supports the modeling results.

Current Air Quality Analysis

As noted in section II.C. above, on September 7, 2011, EPA determined that the Huntington-Ashland Area had attaining data for the 1997 Annual PM2.5 NAAQS based upon data for the 3-year period 2007-2009, with a design value (i.e., the highest 3-year average of annual mean PM2.5 concentrations) of 14.3 μg/m[3] . In that same notice EPA noted that the Area also had attaining data for the 3-year period 2008-2010, with a design value of 13.1 μg/m[3] . These data, which have been quality-assured, certified, and recorded in EPA's Air Quality System (AQS), are summarized in Tables 8 and 9 below. In addition, monitoring data thus far available, but not yet certified, in the AQS database for 2011 show that this Area continues to meet the 1997 Annual PM2.5 NAAQS. The continuing decrease in PM2.5 concentrations in the Area supports Kentucky's determination that current measures were sufficient to bring the Area into attainment by no later than the required attainment date of April 5, 2010.

Table 8—2007-2009 Annual Average Concentrations in the Huntington-Ashland Area

Site nameCountySite No.Annual average concentration (μg/m3)
HuntingtonCabell, WV54-011-00061 14.3
Ashland Primary (FIVCO)Boyd, KY21-019-001712.4
Lawrence County HospitalLawrence, OH39-087-00102 13.3
Ironton Department of Transportation (DOT) 3Lawrence, OH39-087-001212.2

Table 9—2008-2010 Annual Average Concentrations in the Huntington-Ashland Area

Site nameCountySite No.Annual average concentration (μg/m3)
HuntingtonCampbell54-011-000613.1
Ashland Primary (FIVCO)Boyd21-019-001711.4
Ironton DOT 4Lawrence39-087-001212.2

4. Reasonably Available Control Measures/Reasonably Available Control Technology (RACM/RACT)

a. Requirements for RACM/RACT

CAA section 172(c)(1) requires that each attainment plan “provide for the implementation of all reasonably available control measures as expeditiously as practicable (including such reductions in emissions from the existing sources in the area as may be obtained through the adoption, at a minimum, of reasonably available control technology), and shall provide for attainment of the national primary ambient air quality standards.” EPA interprets RACM, including RACT, under section 172 as measures that a state finds are both reasonably available and contribute to attainment as expeditiously are practicable in the nonattainment area. 40 CFR 51.1010; 72 FR 20586, 20612.

States are required to evaluate RACM/RACT for direct PM2.5 emissions and all of the area's attainment plan precursors. 40 CFR 51.1002(c); 72 FR 20586,20589-97. The state must address SO2 as a PM2.5 attainment plan precursor and evaluate sources of SO2 emissions in the state for control measures. The state must address NOX as a PM2.5 attainment plan precursor and evaluate sources of NOX emissions in the state for control measures, unless the state and EPA provide an appropriate technical demonstration for a specific area showing that NOX emissions from sources in the state do not significantly contribute to PM2.5 concentrations in the nonattainment area. Also, because EPA concluded that VOCs and ammonia are presumptively not regulatory precursors for PM2.5, the state is not required to evaluate RACM/RACT for sources of VOCs or ammonia unless there is a determination supported by an appropriate demonstration that such emissions need to be regulated for expeditious attainment of the NAAQS in the specific area.

For PM2.5 attainment plans, the PM2.5 Implementation Rule requires a combined approach to RACM and RACT under subpart 1 of Part D of the CAA (“Plan Requirements for Nonattainment Areas/Nonattainment Areas in General”). Subpart 1, unlike subparts 2 and 4, does not identify specific source categories for which EPA must issue control technique documents or guidelines and does not identify specific source categories for state and EPA evaluation during attainment plan development. 72 FR 20586, 20610. Rather, under subpart 1, EPA considers RACT to be part of an area's overall RACM obligation consistent with the section 172 definition. Because the variable nature of the PM2.5 problem in different nonattainment areas may require states to develop attainment plans that address widely disparate circumstances, EPA determined not only that states should have flexibility with respect to RACM/RACT controls but also that in areas needing significant emission reductions, RACM/RACT controls on smaller sources may be necessary to reach attainment as expeditiously as practicable. 72 FR 20586, 20612 and 20615. Thus, under the PM2.5 Implementation Rule, RACT and RACM are those reasonably available measures that contribute to attainment as expeditiously as practicable in the specific nonattainment area. 40 CFR 51.1010; 72 FR 20586, 20612.

The PM2.5 Implementation Rule requires that attainment plans include the list of measures that a state considered and information sufficient to show that the state met all requirements for the determination of what constitutes RACM/RACT in a specific nonattainment area. 40 CFR 51.1010(a). In addition, the rule requires that the state, in determining whether a particular emissions reduction measure or set of measures must be adopted as RACM/RACT, consider the cumulative impact of implementing the available measures and to adopt as RACM/RACT any potential measures that are reasonably available considering technological and economic feasibility if, considered collectively, they would advance the attainment date by one year or more. If a measure or measures is not necessary for expeditious attainment of the NAAQS in the area, then by definition that measure is not RACM/RACT for purposes of the 1997 PM2.5 NAAQS in that area. Any measures that are necessary to meet these requirements which are not already either federally promulgated, part of the state's SIP, or otherwise creditable in SIPs must be submitted in enforceable form as part of a state's attainment plan for the area. 72 FR 20586, 20614.

Guidance provided in the PM2.5 Implementation Rule for evaluating RACM/RACT level controls for an area also indicates that there could be flexibility with respect to those areas that were predicted to attain the 1997 PM2.5 NAAQS within five years of designation as a result of existing national or local measures. 72 FR 20586, 20612. In such circumstances, the state may conduct a more limited RACM/RACT analysis that does not involve additional air quality modeling. Moreover, the RACM/RACT analysis for such area would focus on a review of reasonably available measures, the estimation of potential emissions reductions, and the evaluation of the time needed to implement the measures. Thus, the PM2.5 Implementation Rule guidance recommends that an analysis for those areas expected to attain within five years of designation as a nonattainment area for the 1997 PM2.5 NAAQS may be a less rigorous than for areas expected to attain later.

A more comprehensive discussion of the RACM/RACT requirement for PM2.5 attainment plans and EPA's guidance for it can be found in the preamble to the PM2.5 Implementation Rule. 72 FR 20586, 20609-20633.

b. Kentucky's Analysis of Pollutants and Sources for the Huntington-Ashland Area

Kentucky's analysis, which appears in chapter 7 of the attainment plan submission, evaluates sources of PM2.5, SO2, and NOX located in the nonattainment area for potential control as RACM/RACT. The Commonwealth determined that controls of sources of VOCs or ammonia would not be necessary for expeditious attainment of the NAAQS in this area. EPA agrees that Kentucky's determination is supported by its analysis. The Commonwealth's determination with respect to which pollutants the plan should evaluate is discussed in chapter 1 of the submittal.

After evaluating which pollutants should be addressed in the attainment plan, the Commonwealth identified all source categories of those emissions located within the nonattainment area to determine available controls that could advance the attainment date by one year or more. See Appendix M of the attainment plan submittal. Based on the emissions inventory and other information, the Commonwealth identified several source categories as sources that should be evaluated for controls. Stationary source measure categories identified include stationary diesel engine retrofit, rebuild or replacements; new or upgraded emission control requirements for direct PM2.5 emissions at stationary sources; improved capture of particulate emissions to increase the amount of PM2.5 ducted to control devices; new or upgraded emission controls for PM2.5 precursors at stationary sources; energy efficiency measures to reduce fuel consumption and associated pollutant emissions; and measures to reduce fugitive dust from industrial sites. Mobile source measure categories identified include on-road diesel engine retrofits for school buses, trucks and transit buses using EPA verified technologies; nonroad diesel engine retrofit, rebuild or replacement; diesel idling programs for trucks, locomotive, and other mobile sources; transportation control measures, including those listed in section 108(f) of the CAA and other transportation demand management and transportation systems management strategies; programs to reduce emissions or accelerate retirement of high emitting vehicles, boats, and lawn and garden equipment; emissions testing and repair/maintenance programs for on-road vehicles, nonroad heavy-duty vehicles and equipment; programs to expand use of clean burning fuels; low emissions specifications for equipment or fuel used for large construction contracts, industrial facilities, ship yards, airports, and public or private vehicle fleets; and opacity or other emissions standards for “gross-emitting” diesel equipment or vessels. Area source measure categories identified include new open burning regulations and/or measures to improve program effectiveness such as programs to reduce or eliminate burning of land clearing vegetation; programs to reduce emissions from woodstoves and fireplaces including outreach programs, curtailments during days with expected high ambient levels of PM2.5, and programs to encourage replacement of woodstoves when houses are sold; controls on emissions from charbroiling or other commercial cooking operations; and reduced solvent usage or solvent substitution.

In accordance with 40 CFR 51.1010, the attainment demonstration component for a PM2.5 nonattainment area SIP is required to demonstrate that all RACM (including RACT for stationary sources) necessary to demonstrate attainment as expeditiously as practicable have been adopted. The cumulative impact of implementing available measures must be considered in determining whether a particular emission reduction measure or set of measures is required to be adopted as RACM. Potential measures that are reasonably available considering technical and economic feasibility must be adopted as RACM if, considered collectively, they would advance the attainment date by one year or more. Therefore, since Kentucky demonstrated attainment of the 1997 PM2.5 NAAQS in the Kentucky portion of the Huntington-Ashland Area by the end of 2009, any RACM measures would have needed to be in effect at the beginning of 2008 to have had any potential to advance the attainment date by at least one year.

Through participation in regional planning efforts of the Southeast Regional Planning Organization, VISTAS and the ASIP, Kentucky has evaluated potential control measures to attain the fine particle. For the relevant source categories, the Commonwealth evaluated the potential control measures that would be considered reasonable for the Huntington-Ashland Area, in light of timing and other considerations consistent with EPA's guidance. DAQ determined that there were no additional measures that could be adopted by January 1, 2008. In addition, existing measures and measures planned for implementation by 2009 enabled the Huntington-Ashland Area to attain the 1997 PM2.5 NAAQS. Therefore, no further actions on RACM or RACT are warranted.

c. Kentucky's Evaluation of RACM/RACT Control Measures for the Huntington-Ashland Area

In accordance with section 172 of the CAA, the Kentucky portion of the Huntington-Ashland Area has adopted all RACM, including RACT, needed to attain the standards “as expeditiously as practicable.” Kentucky's demonstration for attaining the 1997 PM2.5 NAAQS in the Kentucky portion of the Huntington-Ashland Area is based on the following enforceable measures, as discussed in Chapter 5 of the plan: tier 2 vehicle standards; heavy-duty gasoline and diesel highway vehicle standards; large nonroad diesel engine standards; nonroad spark-ignition engines and recreational engines standards; combustion turbine MACTs; VOC 2-, 4-, 7-, and 10-year MACT standards; consent agreements; open burning bans; and fugitive emissions standards.

d. Proposed Action on RACM/RACT Demonstration and Control Strategy

EPA is proposing to approve Kentucky's evaluation of RACM/RACT control measures for the Kentucky portion of the Huntington-Ashland Area. As noted in section C. above, EPA has already determined that the Huntington-Ashland Area has attaining data for the 1997 Annual PM2.5 NAAQS and met the standard by its applicable attainment date of April 5, 2010. EPA's guidance for the PM2.5 Implementation Rule recommends that if an area was predicted through the attainment plan to attain the standard within five years after designation, then the state could submit a more limited RACM/RACT analysis and the state could elect not to do additional modeling.

In light of the fact that the Kentucky portion of the Huntington-Ashland Area is now attaining the standards, EPA proposes to conclude that the attainment plan meets the RACM/RACT requirements of the PM2.5 Implementation Rule and that the level of control in the Commonwealth's attainment plan constitutes RACM/RACT for purposes of the 1997 PM2.5 NAAQS. Because the PM2.5 Implementation Rule defines RACM/RACT as that level of control that is necessary to bring the area into attainment as expeditiously as practicable, the current level of Federally enforceable controls on sources located within the Area is by definition RACM/RACT for this Area for this purpose, given the Area's status as attaining the standard.

5. Reasonable Further Progress

Section 172(c)(2) of the CAA and the PM2.5 Implementation Rule require that attainment plans include a demonstration that reasonable further progress toward meeting air quality standards will be achieved through generally linear incremental improvement in air quality. For the 1997 PM2.5 NAAQS, a state is required to submit a separate RFP plan for any area for which the state seeks an extension of the attainment date beyond 2010. The PM2.5 Implementation Rule set forth that an area that demonstrates attainment within five years of the date of designation will be considered to have satisfied the RFP requirement and is not required to submit a separate RFP plan. See 40 CFR 51.1009(b). The Kentucky attainment plan submittal meets the RFP requirements for the Huntington-Ashland Area by demonstrating that the Area attained the 1997 PM2.5 NAAQS by the 2010 attainment date.

6. Contingency Measures

In accordance with section 172(c)(9) of the CAA, the PM2.5 Implementation Rule requires that PM2.5 attainment plans include contingency measures. 40 CFR 51.1012 and 72 FR at 20642-20646. (April 25, 2007). Contingency measures are additional measures to be implemented in the event that an area fails to meet RFP or fails to attain a standard by its attainment date. These measures must be fully adopted rules or control measures that can be implemented quickly and without additional EPA or state action if the area fails to meet RFP or fails to attain by its attainment date and should contain trigger mechanisms and an implementation schedule. In addition, they should be measures not already included in the SIP control strategy for attaining the standard and should provide for emission reductions equivalent to one year of RFP.

The Kentucky attainment plan describes the contingency measures for the Huntington-Ashland Area as being comprised of Federal measures that were already in place and that would take effect automatically, without further action by the Commonwealth or EPA, if the Area were to fail to attain the standard by its attainment date. As noted in section II.C. of this proposed rulemaking, EPA made a determination, based on complete, quality-assured, quality-controlled, and certified ambient air monitoring data for the 2007-2009 monitoring period, that the Huntington-Ashland Area attained the 1997 Annual PM2.5 NAAQS by the applicable attainment date of April 5, 2010. Because EPA has determined, in accordance with CAA 179(c)(1), that the area attained by its required deadline, no contingency measures for failure to attain by this date need to be implemented. Furthermore, as set forth in the PM2.5 Implementation Rule, areas that attained the NAAQS by the attainment date are considered to have satisfied the requirement to show RFP, and as such do not need to implement contingency measures to make further progress to attainment. Since EPA has determined that the Area has attained by the attainment date, the contingency measures submitted by Kentucky are no longer necessary for the Huntington-Ashland Area to meet RFP requirements or to attain the annual PM2.5 NAAQS by the attainment date.

7. Attainment Date

Kentucky provided a demonstration of attainment of the 1997 PM2.5 NAAQS in the Huntington-Ashland Area by no later than five years after the Area was designated nonattainment. In accordance with the PM2.5 Implementation Rule, areas such as this, demonstrating that they will attain the standard by April 5, 2010, attainment deadline, are considered to have satisfied the requirement to show RFP toward attainment and need not submit a separate RFP plan. For similar reasons, such areas are also not subject to a requirement for a mid-course review.

B. Insignificance Determination for the Mobile Source Contribution to PM2.5 and NOX Emissions

The CAA requires federal actions in nonattainment and maintenance areas to “conform to” the goals of SIPs. See, e.g., CAA section 176. This means that such actions will not cause or contribute to violations of a NAAQS; worsen the severity of an existing violation; or delay timely attainment of any NAAQS or any interim milestone. Actions involving Federal Highway Administration (FHWA) or Federal Transit Administration (FTA) funding or approval are subject to the transportation conformity rule (40 CFR part 93, subpart A). Under this rule, metropolitan planning organizations (MPOs) in nonattainment and maintenance areas coordinate with state air quality and transportation agencies, EPA, and the FHWA and FTA to demonstrate that their metropolitan transportation plans and transportation improvement programs (TIP) conform to applicable SIPs. This is typically determined by showing that estimated emissions from existing and planned highway and transit systems are less than or equal to the motor vehicle emissions budgets contained in a SIP.

For motor vehicle emissions budgets to be approvable, they must meet, at a minimum, EPA's adequacy criteria found at 40 CFR 93.118(e)(4). In certain instances, the Transportation Conformity Rule allows areas to forgo establishment of a MVEB where it is demonstrated that the regional motor vehicle emissions for a particular pollutant or precursor are an insignificant contributor to the air quality problem in an area. The general criteria for insignificance determinations can be found in 40 CFR 93.109(m). Insignificance determinations are based on a number of factors, including the percentage of motor vehicle emissions in context of the total SIP inventory; the current state of air quality as determined by monitoring data for the relevant NAAQS; the absence of SIP motor vehicle control measures; and the historical trends and future projections of the growth of motor vehicle emissions. EPA's rationale for providing for insignificance determinations is described in the July 1, 2004, revision to the Transportation Conformity Rule at 69 FR 40004.[5] Specifically, the rationale is explained on page 40061 under the subsection entitled “XXIII.B. Areas With Insignificant Motor Vehicle Emissions.” Any insignificance determination under review of EPA is subject to the adequacy and approval process for EPA's action on the SIP.

EPA made an insignificance finding through the transportation conformity adequacy process for NOX and directly emitted PM2.5 for the Kentucky portion of the Huntington-Ashland PM2.5 nonattainment area on June 18, 2010 (75 FR 34734). As a result of EPA's insignificance finding, the Kentucky portion of the Huntington-Ashland Area was no longer required to perform regional emissions analyses for either directly emitted PM2.5 or NOX as part of future PM2.5 conformity determinations for the 1997 Annual PM2.5 NAAQS until such time that EPA reviewed and took action on the Huntington-Ashland Area's attainment plan (the subject of today's proposed action). EPA's June 18, 2010, insignificance finding for directly emitted PM2.5 and NOX through the adequacy process (effective on July 6, 2010) only relates to the Kentucky portion of the tri-state Huntington-Ashland Area.[6]

When EPA makes an insignificance determination through the adequacy process for transportation conformity, EPA notes that an adequacy determination does not imply that an insignificance determination in the SIP (i.e., in this case the attainment plan) will ultimately be approved. Consistent with EPA's adequacy review of Kentucky's December 3, 2008, attainment plan and the Agency's subsequent thorough review of the entire SIP submission, EPA is proposing to approve Kentucky's insignificance determination for the mobile source contribution of NOX and PM2.5 emissions to the overall PM2.5 emissions in the Huntington-Ashland Area. As stated previously, the point, area, and nonroad values for Lawrence County in the December 8, 2008 submittal were for the entire county, not just the census block that U.S.EPA designated as nonattainment. The on-road mobile emissions were determined specifically for the designated portion of Lawrence County. On May 26, 2011, at the request of EPA, the Commonwealth submitted updated tables to include information on point source emissions from the designated census block and population based apportionment of the area and non-road sectors to support the mobile source insignificance finding.

EPA finds that Kentucky's SIP submittal meets the criteria in the transportation conformity rules for an insignificance finding for both NOX and PM2.5 contribution from motor vehicles in the Kentucky portion of the Huntington-Ashland Area. That is, EPA finds that the SIP submittal demonstrates that, for NOX and PM2.5, regional motor vehicle emissions are an insignificant contributor to the annual PM2.5 concentrations in the Kentucky portion of the Area. This finding is based on the following factors:

  • Tables 8.2-3 and 8.2-5 of Kentucky's submittal, as revised on May 26, 2011, demonstrate that the on-road NOX and PM2.5 emissions in 2009 for the Kentucky portion of the Area are only 7.43 percent and 0.97 percent, respectively, of the total emissions for the Kentucky portion of the Area.
  • The tables also show that mobile source emissions of NOX and PM2.5 are declining. Specifically, NOX and PM2.5 mobile emissions were projected to decrease by approximately 28 percent and 40 percent, respectively, between the 2002 and 2009. The decrease in NOX and PM2.5 emissions were expected during a time when the VMT were expected to increase by 16 percent in the Kentucky portion of the Area.
  • There have been no SIP requirements for motor vehicles control measures for the Kentucky portion of the Area.
  • According to the Ashland Area Metropolitan Planning Organization (Ashland MPO) analysis, the projected mobile source emissions to 2030 indicate that there is no reason to expect highway motor vehicle growth that would cause a violation of the 1997 Annual PM2.5 NAAQS.
  • As described above, the area has attained the 1997 Annual PM2.5 standard and EPA is proposing to approve the attainment plan for the Kentucky portion of the area.

As discussed above, the Area is not currently required to perform a regional emissions analysis for the Kentucky portion of the Huntington-Ashland Area based on the adequacy determination for the finding that on-road emissions of NOX and direct PM2.5 are insignificant contributors to the area's PM2.5 air quality problem. Today EPA is proposing to approve that insignificance finding as part of the state's attainment plan for the Area. If finalized, such approval it would serve to confirm that the Kentucky portion of the Area is not required to perform a regional emissions analysis for either directly emitted PM2.5 or NOX as a part of future PM2.5 conformity determinations for the 1997 Annual PM2.5 standard.[7] PM2.5 hot-spot analysis will continue to apply for required projects under 40 CFR 93.116 and 93.123(b) of the Transportation Conformity Rule.

Weighing all the factors for an insignificance finding, particularly the minor contribution of mobile source NOX and PM2.5, EPA has determined that the NOX and PM2.5 contribution from motor vehicles emissions to the Annual PM2.5 pollution for the Kentucky portion of the Area are insignificant. EPA's insignificance finding should be considered and specifically noted in the transportation conformity documentation that is prepared for this area.

The insignificance determination that Kentucky submitted for the Huntington-Ashland Area was developed with projected mobile source emissions derived using the MOBILE6 motor vehicle emissions model. EPA is proposing to approve the inventory and the insignificance determination because this model was the most current model available at the time Kentucky was performing its analysis. However, EPA has now issued an updated motor vehicle emissions model known as Motor Vehicle Emission Simulator or MOVES. In its announcement of this model, EPA established a two-year grace period for continued use of MOBILE6 (extending to March 2, 2012), after which states (other than California) must use MOVES in conformity determinations for transportation plans and transportation improvement programs.

V. Proposed Action

EPA is proposing to approve Kentucky's annual PM2.5 attainment plan for the Kentucky portion of the Huntington-Ashland Area. EPA has determined that the SIP meets applicable requirements of the CAA, as described in the PM2.5 Implementation Rule. Specifically, EPA is proposing to approve Kentucky's attainment demonstration, including the RACM/RACT analysis; RFP analysis, base-year and attainment-year emissions inventories; and, for transportation conformity purposes, an insignificance determination for PM2.5 and NOX for the mobile source contribution to ambient PM2.5 levels for the Commonwealth's portion of the Huntington-Ashland Area. The requirement for a RFP plan is satisfied because Kentucky demonstrated attainment of the 1997 PM2.5 NAAQS in the Area by April 2010. Also, because EPA has determined that the Area has attained by the attainment date, the contingency measures submitted by Kentucky are no longer necessary for the Huntington-Ashland Area to meet RFP requirements or to attain the annual PM2.5 NAAQS by the attainment date.

VI. Statutory and Executive Order Reviews

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 approves 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 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 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 Commonwealth, and EPA notes that it will not impose substantial direct costs on tribal governments or preempt tribal law.

List of Subjects

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

Dated: January 20, 2012.

A. Stanley Meiburg,

Acting Regional Administrator, Region 4.

Footnotes

1.  West Virginia has a collocated monitor in place at the same site for quality assurance purposes. The primary monitor, and not the collocated monitor, is used to determine compliance with the PM2.5 NAAQS. Since the collocated monitor takes fewer readings than the primary monitor, its average annual values may be unrepresentatively high. (See 40 CFR Part 50, Appendix N, 3(d)(1).)

2.  The LCH Site was shut-down in February 2008. The Ironton DOT site began operation on the same day the LCH Site ceased monitoring.

3.  The Ironton DOT site did not begin operation until February 2008.

4.  The Ironton DOT site began operation in February 2008 and thus did collect 75 percent for the first quarter of 2008. However, this was a new site and monitoring data did meet 75 percent completeness for the remainder of the quarter and for the subsequent quarters. As such, EPA does not consider the first quarter data to be incomplete.

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5.  Since the July 1, 2004, revision, 40 CFR 93.109 was again revised on March 24, 2010 because of the Transportation Conformity Rule PM2.5 and PM10 Amendments update. In the 2004 preamble and rule, the insignificance determinations were outlined in 40 CFR 93.109(k). Due to renumbering of this section in the 2010 update, the provisions for insignificance determinations are now located at 40 CFR 93.109(m).

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6.  In a letter dated October 23, 2009, EPA informed the State of Ohio that regional mobile emissions of direct PM2.5 and NOX are insignificant for transportation conformity purposes as well. That insignificance determination took effect on December 22, 2009. EPA will review the adequacy of the West Virginia submittal in a separate action.

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7.  If Kentucky submits a redesignation request and maintenance plan for its portion of the Huntington-Ashland WV-KY-OH PM2.5 nonattainment area and believes that on-road emissions of NOX and direct PM2.5 remain insignificant during the maintenance period, the maintenance plan will need to include information to support a finding that on-road emissions of NOX and direct PM2.5 continue to be insignificant during the maintenance period. The insignificance finding for the attainment demonstration does not automatically continue to apply to the maintenance plan.

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[FR Doc. 2012-1938 Filed 1-27-12; 8:45 am]

BILLING CODE 6560-50-P