2011-24373. Approval and Promulgation of Air Quality Implementation Plans; Indiana; Redesignation of the Indianapolis Area to Attainment of the 1997 Annual Standard for Fine Particulate Matter

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Direct final rule.

SUMMARY:

EPA is approving Indiana's request to redesignate the Indianapolis, Indiana nonattainment area (Hamilton, Hendricks, Johnson, Marion, and Morgan Counties) to attainment for the 1997 annual National Ambient Air Quality Standard (NAAQS or standard) for fine particulate matter (PM_2.5), because the request meets the statutory requirements for redesignation under the Clean Air Act (CAA). The Indiana Department of Environmental Management (IDEM) submitted this request to EPA on October 20, 2009 and supplemented it on May 31, 2011. EPA's approval involves several additional related actions. EPA is making a determination that the Indianapolis area has attained the 1997 annual PM_2.5 standard. EPA is approving, as a revision to the Indiana State Implementation Plan (SIP), the State's plan for maintaining the 1997 annual PM_2.5 NAAQS through 2025 in the area. EPA is approving the 2006 emissions inventory for the Indianapolis area as meeting the comprehensive emissions inventory requirement of the CAA. Finally, EPA finds adequate and is approving Indiana's Nitrogen Oxides (NO_X) and PM_2.5 Motor Vehicle Emission Budgets (MVEBs) for 2015 and 2025 for the Indianapolis area.

DATES:

This direct final rule will be effective November 28, 2011, unless EPA receives adverse comments by October 27, 2011.

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-R05-OAR-2009-0839, by one of the following methods:

• http://www.regulations.gov: Follow the on-line instructions for submitting comments.
• E-mail: [e-mail].
• Fax: [phone].
• Mail: Doug Aburano, Chief, Control Strategies Section, Air Programs Branch (AR-18J), U.S. Environmental Protection Agency, 77 West Jackson Boulevard, Chicago, Illinois 60604.
• Hand Delivery: Doug Aburano, Control Strategies Section, Air Programs Branch, (AR-18J), U.S. Environmental Protection Agency, 77 West Jackson Boulevard, 18th Floor, Chicago, Illinois 60604. Such deliveries are only accepted during the Regional Office's normal hours of operation, and special arrangements should be made for deliveries of boxed information. The Regional Office official hours of business are Monday through Friday, 8:30 a.m. to 4:30 p.m., excluding Federal holidays.

Instructions: Direct your comments to Docket ID No. EPA-R05-OAR-2009-0839. 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 e-mail. 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 e-mail comment directly to EPA without going through http://www.regulations.gov, your e-mail 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 and viruses.

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 U.S. Environmental Protection Agency, Region 5, Air and Radiation Division, 77 West Jackson Boulevard, Chicago, Illinois 60604. This facility is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding Federal holidays. We recommend that you telephone Kathleen D'Agostino at [phone] before visiting the Region 5 office.

FOR FURTHER INFORMATION CONTACT:

Kathleen D'Agostino, Environmental Scientist, Attainment Planning and Maintenance Section, Air Programs Branch (AR-18J), Environmental Protection Agency, Region 5, 77 West Jackson Boulevard, Chicago, Illinois 60604, [phone], or [e-mail].

SUPPLEMENTARY INFORMATION:

Throughout this document whenever “we,” “us,” or “our” is used, we mean EPA. This supplementary information section is arranged as follows:

I. What actions is EPA taking?

II. What is the background for these actions?

III. What are the criteria for redesignation to attainment?

IV. What is EPA's analysis of the state's request?

A. Attainment Determination and Redesignation

B. Adequacy of Indiana's MVEBs

C. 2006 Comprehensive Emissions Inventory

V. Summary of Actions

VI. Statutory and Executive Order Reviews

I. What actions is EPA taking?

EPA is making a determination that the Indianapolis area is attaining the 1997 annual PM_2.5 standard and that the area has met the requirements for redesignation under section 107(d)(3)(E) of the CAA. EPA is thus approving the request from IDEM to change the legal designation of the Indianapolis area from nonattainment to attainment for the 1997 annual PM_2.5 NAAQS. EPA is also taking several additional actions related to Indiana's PM_2.5 redesignation request, as discussed below.

EPA is approving Indiana's PM_2.5 maintenance plan for the Indianapolis area as a revision to the Indiana SIP (such approval being one of the CAA criteria for redesignation to attainment status). The maintenance plan is designed to keep the Indianapolis area in attainment of the 1997 annual PM_2.5 NAAQS through 2025.

EPA is approving 2006 emissions inventories for primary PM_2.5,^[1] NO_X, and Sulfur Dioxide (SO₂),^[2] documented in Indiana's May 31, 2011, PM_2.5 redesignation request supplemental submittal. These emissions inventories satisfy the requirement in section 172(c)(3) of the CAA for a comprehensive, current emission inventory.

Finally, EPA finds adequate and is approving 2015 and 2025 primary PM_2.5 and NO_X MVEBs for the Indianapolis area. These MVEBs will be used in future transportation conformity analyses for the area.

II. What is the background for these actions?

The first air quality standards for PM_2.5 were promulgated on July 18, 1997, at 62 FR 38652. EPA promulgated an annual standard at a level of 15 micrograms per cubic meter (µg/m³) of ambient air, based on a three-year average of the annual mean PM_2.5concentrations at each monitoring site. In the same rulemaking, EPA promulgated a 24-hour PM_2.5 standard at 65 µg/m³, based on a three-year average of the annual 98th percentile of 24-hour PM_2.5 concentrations at each monitoring site.

On January 5, 2005, at 70 FR 944, EPA published air quality area designations and classifications for the 1997 annual PM_2.5 standard based on air quality data for calendar years 2001-2003. In that rulemaking, EPA designated the Indianapolis, IN area as nonattainment for the 1997 annual PM_2.5 standard.

On October 17, 2006, at 71 FR 61144, EPA retained the annual PM_2.5 standard at 15 µg/m³ (2006 annual PM_2.5 standard), but revised the 24-hour standard to 35 µg/m³, based again on the three-year average of the annual 98th percentile of the 24-hour PM_2.5 concentrations. In response to legal challenges of the 2006 annual PM_2.5 standard, the U.S. Court of Appeals for District of Columbia Circuit (D.C. Circuit) remanded this standard to EPA for further consideration. See American Farm Bureau Federation and National Pork Producers Council, et al. v. EPA, 559 F.3d 512 (D.C. Cir. 2009). However, given that the 1997 and 2006 annual PM_2.5 standards are essentially identical, attainment of the 1997 annual PM_2.5 standard would also indicate attainment of the remanded 2006 annual standard. Since the Indianapolis area is designated as nonattainment only for the 1997 annual PM_2.5 standard, today's proposed action addresses redesignation to attainment only for this standard.

Fine particulate pollution can be emitted directly from a source (primary PM_2.5) or formed secondarily through chemical reactions in the atmosphere involving precursor pollutants emitted from a variety of sources. Sulfates are a type of secondary particulate formed from SO₂ emissions from power plants and industrial facilities. Nitrates, another common type of secondary particulate, are formed from combustion of NO_X emissions from power plants, mobile sources, and other combustion sources.

III. What are the criteria for redesignation to attainment?

The CAA sets forth the requirements for redesignating a nonattainment area to attainment. Specifically, section 107(d)(3)(E) of the CAA allows redesignation provided that: (1) The Administrator determines that the area has attained the applicable NAAQS; (2) the Administrator has fully approved the applicable SIP for the area under section 110(k) of the CAA; (3) the Administrator determines that the improvement in air quality is due to permanent and enforceable reductions in emissions resulting from the implementation of the applicable SIP, Federal emission control regulations, and other permanent and enforceable emission reductions; (4) the Administrator has fully approved a maintenance plan for the area meeting the requirements of section 175A of the CAA; and, (5) the state containing the area has met all requirements applicable to the area for purposes of redesignation under section 110 and part D of the CAA.

IV. What is EPA's analysis of the state's request?

A. Attainment Determination and Redesignation

EPA is making a determination that the Indianapolis area has attained the 1997 annual PM_2.5 standard and that the area has met all other applicable redesignation criteria under CAA section 107(d)(3)(E). The basis for EPA's approval of the redesignation request is as follows:

1. The Area Has Attained the 1997 Annual PM_2.5 NAAQS (Section 107(d)(3)(E)(i))

EPA is making a determination that the Indianapolis area has attained the 1997 annual PM_2.5 NAAQS. An area may be considered to be attaining the 1997 annual PM_2.5 NAAQS if there are no violations, as determined in accordance with 40 CFR 50.7 and part 50, Appendix N, based on three complete consecutive calendar years of quality-assured air quality monitoring data. To attain this standard, the three-year average of annual means must not exceed 15.0 μg/m³ at all relevant monitoring sites in the subject area. Under 40 CFR part 50, Appendix N 4.1, a year of PM_2.5 data meets completeness requirements when “at least 75 percent of the scheduled sampling days for each quarter has valid data.”

The redesignation request includes monitoring data showing attainment of the standard for the 2006-2008, 2007-2009, and 2008-2010 time periods. All of the PM_2.5 monitors in the Indianapolis area are located in Marion County. Table 1, below, provides a summary of the PM_2.5 annual air quality monitoring data for the years 2006-2010. Table 2, below, provides the three-year average of annual means for the 2006-2008, 2007-2009, and 2008-2010 time periods.

Table 1—PM_2.5 Annual Mean PM_2.5 Concentrations for the Indianapolis Area

[µg/m³]

Monitor	Yearly annual mean
	2006	2007	2008	2009	2010
Indianapolis—Washington Park 180970078	14.14	15.66	13.02	12.11	12.86
Indianapolis—W. 18th Street 180970081	14.12	16.07	13.75	12.96	14.03
Indianapolis—E. Michigan Street 180970083	14.15	15.93	13.17	12.40	13.91

Table 2—Three-Year Average of the Annual Mean PM_2.5 Concentrations for the Indianapolis Area

[µg/m³]

Monitor	2006-2008	2007-2009	2008-2010
Indianapolis—Washington Park 180970078	14.3	13.6	12.7
Indianapolis—E. 75th Street 180970081	14.6	14.3	13.6
Indianapolis—E. Michigan Street 180970083	14.4	13.8	13.2

The data in tables 1 and 2 show that all relevant PM_2.5 monitors in the Indianapolis PM_2.5 nonattainment area have recorded PM_2.5 concentrations attaining the 1997 annual PM_2.5 standard during the 2006-2008, 2007-2009, and 2008-2010 time periods. These annual average PM_2.5 concentrations are based on complete PM_2.5 monitoring data that have been quality-assured and stored in EPA's Air Quality System (AQS) database. Therefore, EPA concludes that the Indianapolis area has attained the 1997 PM_2.5 standard. Preliminary data available for 2011 are consistent with continued attainment.

2. The Area Has Met All Applicable Requirements Under Section 110 and Part D; and the Area Has a Fully Approved SIP Under Section 110(k) (Sections 107(d)(3)(E)(v) and 107(d)(3)(E)(ii))

We have determined that Indiana's SIP meets all applicable SIP requirements for purposes of redesignation for the Indianapolis area under section 110 of the CAA (general SIP requirements) and all SIP requirements currently applicable for purposes of redesignation under part D of Title I of the CAA, in accordance with section 107(d)(3)(E)(v). In addition, with the exception of the emissions inventory under section 172(c)(3), we have approved all applicable requirements of the Indiana SIP for purposes of redesignation, in accordance with section 107(d)(3)(E)(ii). As discussed below, in this action EPA is approving Indiana's 2006 emissions inventory as meeting the section 172(c)(3) comprehensive emissions inventory requirement.

In making these determinations, we have ascertained which SIP requirements are applicable to the area for purposes of redesignation, and have determined that there are SIP measures meeting those requirements and that they are fully approved under section 110(k) of the CAA.

a. The Indianapolis Area Has Met All Applicable Requirements for Purposes of Redesignation Under Section 110 and Part D of the CAA

i. Section 110 General SIP Requirements

Section 110(a) of Title I of the CAA contains the general requirements for a SIP. Section 110(a)(2) provides that the implementation plan submitted by a state must have been adopted by the state after reasonable public notice and hearing, and, among other things, must: Include enforceable emission limitations and other control measures, means or techniques necessary to meet the requirements of the CAA; provide for establishment and operation of appropriate devices, methods, systems, and procedures necessary to monitor ambient air quality; provide for implementation of a source permit program to regulate the modification and construction of any stationary source within the areas covered by the plan; include provisions for the implementation of part C, Prevention of Significant Deterioration (PSD) and part D, New Source Review (NSR) permit programs; include criteria for stationary source emission control measures, monitoring, and reporting; include provisions for air quality modeling; and provide for public and local agency participation in planning and emission control rule development.

Section 110(a)(2)(D) of the CAA requires that SIPs contain measures to prevent sources in a state from significantly contributing to air quality problems in another state. EPA holds that the requirements linked with a particular nonattainment area's designation are the relevant measures to evaluate in reviewing a redesignation request. The transport SIP submittal requirements, where applicable, continue to apply to a state regardless of the designation of any one particular area in the state. Thus, we conclude that these requirements should not be construed to be applicable requirements for purposes of redesignation.

Further, we conclude the other section 110 elements described above that are not connected with nonattainment plan submissions and not linked with an area's attainment status are also not applicable requirements for purposes of redesignation. A state remains subject to these requirements after an area is redesignated to attainment. We conclude that only the section 110 and part D requirements that are linked with a particular area's designation are the relevant measures which we may consider in evaluating a redesignation request. This approach is consistent with EPA's existing policy on applicability of conformity and oxygenated fuels requirements for redesignation purposes, as well as with section 184 ozone transport requirements. See Reading, Pennsylvania, proposed and final rulemakings (61 FR 53174-53176, October 10, 1996) and (62 FR 24826, May 7, 1997); Cleveland-Akron-Lorain, Ohio, final rulemaking (61 FR 20458, May 7, 1996); and Tampa, Florida, final rulemaking (60 FR 62748, December 7, 1995). See also the discussion on this issue in the Cincinnati, Ohio 1-hour ozone redesignation (65 FR 37890, June 19, 2000), and in the Pittsburgh, Pennsylvania 1-hour ozone redesignation (66 FR 50399, October 19, 2001).

We have reviewed Indiana's SIP and have concluded that it meets the general SIP requirements under section 110 of the CAA to the extent they are applicable for purposes of redesignation. EPA has previously approved provisions of the Indiana SIP addressing section 110 requirements (including provisions addressing particulate matter) at 40 CFR 52.770. On December 7, 2007, September 9, 2008, March 23, 2011, and April 7, 2011, Indiana made submittals addressing “infrastructure SIP” elements required by section 110(a)(2) of the CAA. EPA approved elements of Indiana's submittals on July 13, 2011, at 76 FR 41075. The requirements of section 110(a)(2), however, are statewide requirements that are not linked to the PM_2.5 nonattainment status of the Indianapolis area. Therefore, EPA believes that these SIP elements are not applicable requirements for purposes of review of the State's PM_2.5 redesignation request.

ii. Part D Requirements

EPA has determined that, upon approval of the base year emissions inventories discussed in section IV.C. of this rulemaking, the Indiana SIP will meet the applicable SIP requirements for the Indianapolis area applicable for purposes of redesignation under part D of the CAA. Subpart 1 of part D, found in sections 172-176 of the CAA, sets forth the basic nonattainment requirements applicable to all nonattainment areas.

Subpart 1 Section 172 Requirements

For purposes of evaluating this redesignation request, the applicable section 172 SIP requirements for the Indianapolis area are contained in sections 172(c)(1)-(9). A thorough discussion of the requirements contained in section 172 can be found in the General Preamble for Implementation of Title I (57 FR 13498, April 16, 1992).

Section 172(c)(1) requires the plans for all nonattainment areas to provide for the implementation of all Reasonably Available Control Measures (RACM) as expeditiously as practicable and to provide for attainment of the primary NAAQS. EPA interprets this requirement to impose a duty on all nonattainment areas to consider all available control measures and to adopt and implement such measures as are reasonably available for implementation in each area as components of the area's attainment demonstration. Because attainment has been reached, no additional measures are needed to provide for attainment, and section 172(c)(1) requirements are no longer considered to be applicable as long as the area continues to attain the standard until redesignation. See 40 CFR 51.1004(c).

The Reasonable Further Progress (RFP) requirement under section 172(c)(2) is defined as progress that must be made toward attainment. This requirement is not relevant for purposes of redesignation because the Indianapolis area has monitored attainment of the 1997 annual PM_2.5 NAAQS. Id. The requirement to submit the section 172(c)(9) contingency measures is similarly not applicable for purposes of redesignation. Id.

Section 172(c)(3) requires submission and approval of a comprehensive, accurate, and current inventory of actual emissions. Indiana submitted a 2006 base year emissions inventory along with the redesignation request. As discussed below in section IV.C., EPA is approving the 2006 base year inventory as meeting the section 172(c)(3) emissions inventory requirement for the Indianapolis area.

Section 172(c)(4) requires the identification and quantification of allowable emissions for major new and modified stationary sources in an area, and section 172(c)(5) requires source permits for the construction and operation of new and modified major stationary sources anywhere in the nonattainment area. EPA approved Indiana's current NSR program on October 7, 1994 (59 FR 51108). Nonetheless, since PSD requirements will apply after redesignation, the area need not have a fully-approved NSR program for purposes of redesignation, provided that the area demonstrates maintenance of the NAAQS without part D NSR. A detailed rationale for this view is described in a memorandum from Mary Nichols, Assistant Administrator for Air and Radiation, dated October 14, 1994, entitled, “Part D New Source Review Requirements for Areas Requesting Redesignation to Attainment.” Indiana has demonstrated that the Indianapolis area will be able to maintain the standard without part D NSR in effect; therefore, the State need not have a fully approved part D NSR program prior to approval of the redesignation request. The State's PSD program will become effective in the Indianapolis area upon redesignation to attainment. See rulemakings for Detroit, Michigan (60 FR 12467-12468, March 7, 1995); Cleveland-Akron-Lorain, Ohio (61 FR 20458, 20469-20470, May 7, 1996); Louisville, Kentucky (66 FR 53665, October 23, 2001); and Grand Rapids, Michigan (61 FR 31834-31837, June 21, 1996).

Section 172(c)(6) requires the SIP to contain control measures necessary to provide for attainment of the standard. Because attainment has been reached, no additional measures are needed to provide for attainment.

Section 172(c)(7) requires the SIP to meet the applicable provisions of section 110(a)(2). As noted above, we find that the Indiana SIP meets the section 110(a)(2) requirements applicable for purposes of redesignation.

Subpart 1 Section 176 Conformity Requirements

Section 176(c) of the CAA requires states to establish criteria and procedures to ensure that Federally-supported or funded activities, including highway projects, conform to the air quality planning goals in the applicable SIPs. The requirement to determine conformity applies to transportation plans, programs, and projects developed, funded, or approved under Title 23 of the U.S. Code and the Federal Transit Act (transportation conformity) as well as to all other Federally-supported or funded projects (general conformity). State transportation conformity regulations must be consistent with Federal conformity regulations relating to consultation, enforcement, and enforceability, which EPA promulgated pursuant to CAA requirements.

EPA approved Indiana's general and transportation conformity SIPs on January 14, 1998 (63 FR 2146) and August 17, 2010 (75 FR 50730), respectively. Section 176(c) of the CAA was amended by provisions contained in the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEALU), which was signed into law on August 10, 2005 (Public Law 109-59). In adopting this revision to the CAA, Congress streamlined the requirements for state conformity SIPs. Indiana is in the process of updating its transportation conformity SIP to meet these new requirements.

Indiana has submitted on-road MVEBs for the Indianapolis area of 353.40 tons per year (tpy) and 317.86 tpy primary PM_2.5 and 14,956.79 tpy and 8,839.80 tpy NO_X for the years 2015 and 2025, respectively. The area must use the MVEBs from the maintenance plan in any conformity determination that is made on or after the effective date of the adequacy finding and maintenance plan approval.

b. The Indianapolis Area Has a Fully Approved Applicable SIP Under Section 110(k) of the CAA

Upon final approval of Indiana's comprehensive 2006 emissions inventory, EPA will have fully approved the Indiana SIP for the Indianapolis area under section 110(k) of the CAA for all requirements applicable for purposes of redesignation. EPA may rely on prior SIP approvals in approving a redesignation request (See page 3 of the September 4, 1992, memorandum from John Calcagni, entitled “Procedures for Processing Requests to Redesignate Areas to Attainment”; Southwestern Pennsylvania Growth Alliance v. Browner, 144 F.3d 984, 989-990 (6th Cir. 1998); Wall v. EPA, 265 F.3d 426 (6th Cir. 2001)) plus any additional measures it may approve in conjunction with a redesignation action. See 68 FR 25413, 25426 (May 12, 2003). Since the passage of the CAA of 1970, Indiana has adopted and submitted, and EPA has fully approved, provisions addressing various required SIP elements under particulate matter standards. In this action, EPA is approving Indiana's 2006 base year emissions inventory for the Indianapolis area as meeting the requirement of section 172(c)(3) of the CAA. No Indianapolis area SIP provisions are currently disapproved, conditionally approved, or partially approved.

3. The Improvement in Air Quality Is Due to Permanent and Enforceable Reductions in Emissions Resulting From Implementation of the SIP and Applicable Federal Air Pollution Control Regulations and Other Permanent and Enforceable Reductions (Section 107(d)(3)(E)(iii))

EPA finds that Indiana has demonstrated that the observed air quality improvement in the Indianapolis area is due to permanent and enforceable reductions in emissions resulting from implementation of the SIP, Federal measures, and other state-adopted measures.

In making this showing, IDEM has calculated the change in emissions between 2002, one of the years used as a basis for designating the Indianapolis area as nonattainment, and 2008, one of the years in the period during which the Indianapolis area monitored attainment. The reduction in emissions and the corresponding improvement in air quality over this time period can be attributed to a number of regulatory control measures that the Indianapolis area and upwind areas have implemented in recent years.

a. Permanent and Enforceable Controls Implemented

The following is a discussion of permanent and enforceable measures that have been implemented in the areas:

i. Federal Emission Control Measures

Reductions in fine particle precursor emissions have occurred statewide and in upwind areas as a result of Federal emission control measures, with additional emission reductions expected to occur in the future. Federal emission control measures include the following:

Tier 2 Emission Standards for Vehicles and Gasoline Sulfur Standards. These emission control requirements result in lower volatile organic compound (VOC), NO_X, and SO₂ emissions from new cars and light duty trucks, including sport utility vehicles. The Federal rules were phased in between 2004 and 2009. The EPA has estimated that, by the end of the phase-in period, the following vehicle NO_X emission reductions will occur nationwide: Passenger cars (light duty vehicles) (77 percent); light duty trucks, minivans, and sports utility vehicles (86 percent); and larger sports utility vehicles, vans, and heavier trucks (69 to 95 percent). Some of the emissions reductions resulting from new vehicle standards occurred during the 2008-2010 attainment period; however additional reductions will continue to occur throughout the maintenance period as new vehicles replace older vehicles. The Tier 2 standards also reduced the sulfur content of gasoline to 30 parts per million (ppm) beginning in January 2006. Most gasoline sold in Indiana prior to January 2006 had a sulfur content of about 500 ppm.

Heavy-Duty Diesel Engine Rule. This rule, which EPA issued in July 2000, limited the sulfur content of diesel fuel beginning in 2004. A second phase took effect in 2007 which reduced fine particle emissions from heavy-duty highway engines and further reduced the highway diesel fuel sulfur content to 15 ppm. The total program is estimated to achieve a 90 percent reduction in primary PM_2.5 emissions and a 95 percent reduction in NO_X emissions for these new engines using low sulfur diesel, compared to existing engines using higher sulfur content diesel. The reductions in fuel sulfur content occurred by the 2008-2010 attainment period. Some of the emissions reductions resulting from new vehicle standards occurred during the 2008-2010 attainment period, however additional reductions will continue to occur throughout the maintenance period as the fleet of older heavy duty diesel engines turns over. The reduction in fuel sulfur content also yielded an immediate reduction in sulfate particle emissions from all diesel vehicles.

Nonroad Diesel Rule. In May 2004, EPA promulgated a new rule for large nonroad diesel engines, such as those used in construction, agriculture, and mining equipment, which established engine emission standards to be phased in between 2008 and 2014. The rule also required reductions to the sulfur content in nonroad diesel fuel by over 99 percent. Prior to 2006, nonroad diesel fuel averaged approximately 3,400 ppm sulfur. This rule limited nonroad diesel sulfur content to 500 ppm by 2006, with a further reduction to 15 ppm, by 2010. The combined engine and fuel rules will reduce NO_X and PM emissions from large nonroad diesel engines by over 90 percent, compared to current nonroad engines using higher sulfur content diesel. The reduction in fuel sulfur content yielded an immediate reduction in sulfate particle emissions from all diesel vehicles. In addition, some emissions reductions from the new engine emission standards were realized over the 2008-2010 time period, although most of the reductions will occur over the maintenance period as the fleet of older nonroad diesel engines turns over.

Nonroad Large Spark-Ignition Engine and Recreational Engine Standards. In November 2002, EPA promulgated emission standards for groups of previously unregulated nonroad engines. These engines include large spark-ignition engines such as those used in forklifts and airport ground-service equipment; recreational vehicles using spark-ignition engines such as off-highway motorcycles, all-terrain vehicles, and snowmobiles; and recreational marine diesel engines. Emission standards from large spark-ignition engines were implemented in two tiers, with Tier 1 starting in 2004 and Tier 2 in 2007. Recreational vehicle emission standards are being phased in from 2006 through 2012. Marine Diesel engine standards were phased in from 2006 through 2009. With full implementation of all of the nonroad spark-ignition engine and recreational engine standards, an overall 72 percent reduction in VOC, 80 percent reduction in NO_X and 56 percent reduction in carbon monoxide (CO) emissions are expected by 2020. Some of these emission reductions occurred by the 2008-2010 attainment period and additional emission reductions will occur during the maintenance period as the fleet turns over.

ii. Control Measures in Upwind Areas

Given the significance of sulfates and nitrates in the Indianapolis area, the area's air quality is strongly affected by regulation of SO₂ and NO_X emissions from power plants.

NO_XSIP Call. On October 27, 1998 (63 FR 57356), EPA issued a NO_X SIP Call requiring the District of Columbia and 22 states to reduce emissions of NO_X. Affected states were required to comply with Phase I of the SIP Call beginning in 2004, and Phase II beginning in 2007. Emission reductions resulting from regulations developed in response to the NO_X SIP Call are permanent and enforceable.

Clean Air Interstate Rule (CAIR). EPA proposed CAIR on January 30, 2004, at 69 FR 4566, promulgated CAIR on May 12, 2005, at 70 FR 25162, and promulgated associated Federal Implementation Plans (FIPs) on April 28, 2006, at 71 FR 25328, in order to reduce SO₂ and NO_X emissions and improve air quality in many areas across Eastern United States. However, on July 11, 2008, the United States Court of Appeals for the District of Columbia Circuit vacated and remanded both CAIR and the associated CAIR FIPs in their entirety. See North Carolina v. EPA, 531 F.3d 836 (D.C. Cir. 2008). EPA petitioned for a rehearing, and the D.C. Circuit issued an order remanding CAIR and the CAIR FIPs to EPA without vacatur. See North Carolina v. EPA, 550 F.3d 1176 (D.C. Cir. 2008). The D.C. Circuit, thereby, left CAIR in place in order to “temporarily preserve the environmental values covered by CAIR” until EPA replaced it with a rule consistent with the Court's opinion. Id. at 1178. The court directed EPA to “remedy CAIR's flaws” consistent with the July 11, 2008, opinion, but declined to impose a schedule on EPA for completing this action. Id).

On August 8, 2011, at 76 FR 48208, EPA promulgated the Cross-State Air Pollution Rule (CSAPR) to address interstate transport of emissions and resulting secondary air pollutants and to replace CAIR. The CAIR, among other things, required NO_X emission reductions that contributed to the air quality improvement in the Indianapolis nonattainment area. The CAIR emission reduction requirements limit emissions through 2011; CSAPR requires similar or greater emission reductions in the relevant areas in 2012 and beyond. CSAPR requires substantial reductions of SO₂ and NO_X emissions from Electric Generating Units (EGUs or power plants) across most of Eastern United States, with implementation beginning on January 1, 2012. In particular, this rule requires reduction of these emissions to levels well below the levels that led to attainment of the 1997 annual PM_2.5 standard in the Indianapolis nonattainment area. Thus the emission reductions that are mandated first by CAIR and then by CSAPR may be considered to be permanent and enforceable. In turn, the air quality improvement in the Indianapolis nonattainment area that has resulted from EGU emission reductions to date (as well as the substantial further air quality improvement that would be expected to result from full implementation of CSAPR) may also be considered to be permanent and enforceable.

b. Emission Reductions

Indiana developed emissions inventories for NO_X, primary PM_2.5, and SO₂ for 2002, one of the years used to designate the areas as nonattainment, and 2008, one of the years the Indianapolis area monitored attainment of the standard.

EGU SO₂ and NO_X emissions were derived from EPA's Clean Air Market's acid rain database. These emissions reflect implementation of the acid rain program and EPA's NO_X SIP call. The 2008 emissions also reflect implementation of CAIR. All other point source emissions were obtained from Indiana's source facility emissions reporting.

Area source emissions for the Indianapolis area for 2002 and 2005 were taken from Indiana's 2002 and 2005 periodic emissions inventories.^[3] The 2005 periodic emission inventory area source emissions were extrapolated to 2008. Source growth factors were supplied by the Lake Michigan Air Directors Consortium (LADCO).

Nonroad mobile source emissions were extrapolated from nonroad mobile source emissions reported in EPA's 2005 National Emissions Inventory (NEI). Contractors were employed by LADCO to estimate emissions for commercial marine vessels and railroads.

On-road mobile source emissions were calculated using EPA's mobile source emission factor model, MOBILE6.2.

Note that all emissions discussed below were documented in appendices B through E of Indiana's May 31, 2011, redesignation request submittal. For these data and additional emissions inventory data, please go to EPA's digital docket for this proposed rule, http://www.regulations.gov,, which includes a digital copy of Indiana's May 31, 2011, submittal.

Emissions data are shown in tables 3 through 5 below.

Table 3—Comparison of 2002 and 2008 NO_X Emission Totals by Source Sector (tpy) for the Indianapolis Area

Sector	NOX
	2002	2008	Net change 2002-2008
Point	8,045.92	6,259.45	−1,786.47
EGU	12,388.02	7,183.98	−5,204.04
Area	5,518.12	4,885.91	−632.21
Nonroad	11,973.65	10,953.68	−1,019.97
On-road	38,059.50	21,494.74	−16,564.76
Total	75,985.21	50,777.76	−25,207.45

Table 4—Comparison of 2002 and 2008 Primary PM_2.5 Emission Totals by Source Sector (tpy) for the Indianapolis Area

Sector	Direct PM2.5
	2002	2008	Net change 2002-2008
Point	653.57	843.05	189.48
EGU	110.66	1,966.49	1,855.83
Area	2,934.93	85.36	−2,849.57
Nonroad	847.73	805.42	−42.31
On-road	670.50	403.67	−266.83
Total	5,217.39	4,103.99	−1,113.40

Table 5—Comparison of 2002 and 2008 SO₂ Emission Totals by Source Sector (tpy) for the Indianapolis Area

Sector	SO2
	2002	2008	Net change 2002-2008
Point	4,835.58	2,415.94	−2,419.64
EGU	68,148.53	38,027.05	−30,121.48
Area	8,676.35	1,830.02	−6,846.33
Nonroad	1,121.00	576.13	−544.87
On-road	1,219.50	653.54	−565.96
Total	84,000.96	43,502.68	−40,498.28

Table 3 shows that the Indianapolis area reduced NO_X emissions by 25,207.45 tpy between 2002 and 2008. Table 4 shows that the Indianapolis area reduced direct PM_2.5 emissions by 1,113.40 tpy between 2002 and 2008. Table 5 shows that the Indianapolis area reduced SO₂ emissions by 40,498.28 tpy between 2002 and 2008.

Because PM_2.5 concentrations in the Indianapolis area are significantly impacted by the transport of sulfates and nitrates, the area's air quality is strongly affected by regulation of SO₂ and NO_X emissions from power plants. Table 6, below, presents actual statewide EGU emissions data compiled by EPA's Clean Air Markets Division for the years 2002 and 2008. Emissions for 2002 reflect implementation of the acid rain program while emissions for 2008 also reflect reductions implemented under CAIR. This table shows emissions for all states that, according to modeling conducted for the final CSAPR, are estimated to contribute at least 0.15 μg/m³ to Indianapolis area annual average PM_2.5 concentrations in the absence of CAIR or CSAPR. (See http://epa.gov/​crossstaterule/​pdfs/​CSAPR_​Ozone%20and%20PM2.5_​Contributions.xls.)

Table 6—Comparison of 2002 and 2008 Statewide EGU NO_X and SO₂ Emissions (tpy) for States Impacting the Indianapolis Area

State	NOX			SO2
	2002	2008	Net change 2002-2008	2002	2008	Net change 2002-2008
Alabama	161,559	112,625	−48,934	448,248	357,547	−90,701
Illinois	174,247	119,930	−54,317	353,699	257,357	−96,342
Indiana	281,146	190,092	−91,054	778,868	565,459	−213,409
Iowa	78,956	49,023	−29,933	127,847	109,293	−18,554
Kentucky	198,599	157,903	−40,696	482,653	344,356	−138,297
Michigan	132,623	107,624	−25,000	342,999	326,501	−16,498
Missouri	139,799	88,742	−51,057	235,532	258,269	22,737
Ohio	370,497	235,049	−135,448	1,132,069	709,444	−422,625
Pennsylvania	200,909	183,658	−17,251	889,766	831,915	−57,851
Tennessee	155,996	85,641	−70,356	336,995	208,069	−128,926
West Virginia	225,371	99,484	−125,887	507,110	301,574	−205,536
Wisconsin	88,970	47,794	−41,175	191,257	129,694	−61,563
Total	2,208,672	1,477,564	−731,108	5,827,042	4,399,478	−1,427,564

Table 6 shows that states impacting the Indianapolis area reduced NO_X and SO₂ emissions from EGUs by 731,108 tpy and 1,427,564 tpy, respectively, between 2002 and 2008.

Based on the information summarized above, Indiana has adequately demonstrated that the improvement in air quality is due to permanent and enforceable emissions reductions.

4. The Area Has a Fully Approved Maintenance Plan Pursuant to Section 175A of the CAA (Section 107(d)(3)(E)(iv))

In conjunction with Indiana's request to redesignate the Indianapolis nonattainment area to attainment status, IDEM submitted a SIP revision to provide for maintenance of the 1997 annual PM_2.5 NAAQS in the area through 2025.

a. What is required in a maintenance plan?

Section 175A of the CAA sets forth the required elements of a maintenance plan for areas seeking redesignation from nonattainment to attainment. Under section 175A, the plan must demonstrate continued attainment of the applicable NAAQS for at least ten years after EPA approves a redesignation to attainment. Eight years after redesignation, the state must submit a revised maintenance plan which demonstrates that attainment will continue to be maintained for ten years following the initial ten-year maintenance period. To address the possibility of future NAAQS violations, the maintenance plan must contain contingency measures with a schedule for implementation as EPA deems necessary to assure prompt correction of any future PM_2.5 violations.

The September 4, 1992, John Calcagni memorandum provides additional guidance on the content of a maintenance plan. The memorandum states that a maintenance plan should address the following items: the attainment emissions inventories, a maintenance demonstration showing maintenance for the ten years of the maintenance period, a commitment to maintain the existing monitoring network, factors and procedures to be used for verification of continued attainment of the NAAQS, and a contingency plan to prevent or correct future violations of the NAAQS.

b. Attainment Inventory

The IDEM developed emissions inventories for NO_X, direct PM_2.5, and SO₂ for 2008, one of the years used to demonstrate monitored attainment of the 1997 annual PM_2.5 standard, as described in section IV.A.3.b., above. The attainment level of emissions is summarized in tables 2 through 4, above.

c. Demonstration of Maintenance

Along with the redesignation request, IDEM submitted revisions to the Indiana PM_2.5 SIP to include a maintenance plan for the Indianapolis area, as required by section 175A of the CAA. This demonstration shows maintenance of the annual PM_2.5 standard through 2025 by showing that current and future emissions of NO_X, direct PM_2.5 and SO₂ for the area remain at or below attainment year emission levels. A maintenance demonstration may be based on such an emissions inventory approach. See Wall v. EPA, 265 F.3d 426 (6th Cir. 2001), Sierra Club v. EPA, 375 F. 3d 537 (7th Cir. 2004). See also 66 FR 53094, 53099-53100 (October 19, 2001), 68 FR 25413, 25430-25432 (May 12, 2003).

Indiana is using emissions inventory projections for the years 2015, 2020, and 2025 to demonstrate maintenance. The projected emissions were estimated by IDEM, with assistance from LADCO, and the Indianapolis Metropolitan Planning Organization.

As noted above, IDEM and others estimating mobile source emissions for the Indianapolis area have used EPA's MOBILE6.2 mobile source emission factor model to estimate mobile source emissions in both the October 20, 2009, submittal and the May 31, 2011, submittal rather than MOVES to estimate mobile source emissions.^[4] EPA is proposing to approve Indiana's continued use of MOBILE6.2 in this maintenance plan. Air quality data indicate that the area has attained the 1997 PM_2.5 annual standard, and large emission reductions are expected in this area and in upwind areas in the coming years, which will maintain the 1997 PM_2.5 annual standard during the maintenance period. If MOVES had been used to estimate on-road mobile source emissions, we believe it would not have changed this conclusion.

In addition, the recent, May 31, 2011, submittal only extended the maintenance period by five years from the maintenance period documented in the October 20, 2009, submittal, and it was not necessary for the newer submittal to revisit earlier years of the maintenance period. This extension of the maintenance period was necessary because: (1) EPA could not act on the original submittal at an earlier date due to issues related to the remand of CAIR; and, (2) Indiana, subsequently, needed to extend the maintenance period to meet CAA maintenance demonstration requirements. Further, consistent with documentation for Question 5 in EPA's “Policy Guidance on the Use of MOVES2010 for State Implementation Plan Development, Transportation Conformity, and Other Purposes” (the MOVES guidance) (http://www.epa.gov/​otaq/​models/​moves/​420b09046.pdf), we have concluded that, since the bulk of the work on the maintenance plan was performed in 2009, before MOVES was released, the continued use of MOBILE6.2 in the maintenance plan is warranted. Even the supplemental work performed by Indiana to support the May 31, 2011, revision was done relatively soon after MOVES was officially released for use in SIPs on March 2, 2010, at 75 FR 9411. Based on these factors, we have concluded that Indiana's continued use of MOBILE6.2 is justified. In addition, the continued use of MOBILE6.2 avoids an adverse impact on State resources as also described in the documentation for Question 5 of the MOVES guidance.

As discussed in section IV.3.a. above, many of the control programs that helped to bring the area into attainment of the standard will continue to achieve additional emission reductions over the maintenance period. These control programs include Tier 2 emission standards for vehicles and gasoline sulfur standards, the heavy-duty diesel engine rule, the nonroad diesel rule, and the nonroad large spark-ignition engine and recreation engine standards. In addition, implementation of CSAPR will result in further reductions in SO₂ and NO_X emissions over the maintenance period. Emissions data for all sources by source sector are shown in tables 7 through 9, below.

Table 7—Comparison of 2008, 2015, 2020, and 2025 NO_X Emission Totals by Source Sector (tpy) for the Indianapolis Area

Sector	NOX
	2008	2015	2020	2025	Net change 2008-2025
Point	6,259.45	6,267.98	6,182.66	6,098.76	−160.69
EGU	7,183.98	6,864.90	6,864.17	6,863.44	−320.54
Area	4,885.91	4,808.82	4,726.75	4,646.40	−239.51
Nonroad	10,953.68	7,146.72	4,961.21	3,544.70	−7,408.98
On-road	21,494.74	12,259.66	9,752.70	7,245.74	−14,249.00
Total	50,777.76	37,348.08	32,487.49	28,399.04	−22,378.72

Table 8—Comparison of 2008, 2015, 2020, and 2025 Direct PM_2.5 Emission Totals by Source Sector (tpy) for the Indianapolis Area

Sector	Direct PM2.5
	2008	2015	2020	2025	Net change 2008-2025
Point	843.05	822.74	806.17	790.01	−53.04
EGU	1,966.49	2,567.84	2,567.83	2,567.81	601.32
Area	85.36	81.77	78.97	76.30	−9.06
Nonroad	805.42	537.76	384.01	281.52	−523.90
On-road	403.67	289.67	275.11	260.54	−143.13
Total	4,103.99	4,299.78	4,112.09	3,976.18	−127.81

Table 9—Comparison of 2008, 2015, 2020, and 2025 SO₂ Emission Totals by Source Sector (tpy) for the Indianapolis Area

Sector	SO2
	2008	2015	2020	2025	Net change 2008-2025
Point	2,415.94	1,631.65	1,604.91	1,578.72	−837.22
EGU	38,027.05	28,314.66	28,314.44	28,314.22	−9,712.83
Area	1,830.02	1,778.03	1,731.62	1,686.72	−143.30
Nonroad	576.13	165.61	89.31	56.66	−519.47
On-road	653.54	498.20	531.68	565.17	−88.37
Total	43,502.68	32,388.15	32,271.96	32,201.49	−11,301.19

Table 7 shows that the NO_X emissions in the Indianapolis area are 22,378.72 tpy less in 2025, the out-year of the maintenance plan, than in attainment year 2008. Table 8 shows that direct PM_2.5 emissions are 127.81 tpy lower in 2025 than in 2008. Table 9 shows that SO₂ emissions are 11,301.19 tpy lower in 2025 than in 2008.

For the interim years of 2015 and 2020, however, in conjunction with the projections for dramatic declines in SO₂ and NO_X emissions in the Indianapolis area, the maintenance plan shows an increase in PM_2.5 emissions. Therefore, further evaluation is needed to judge whether the increase in PM_2.5 emissions, in combination with the decreases in SO₂ and NO_X emissions, is likely to provide for maintenance of the standard during the interim period.

Each of these pollutants is characterized by a different relationship between emissions and air quality. Therefore, simply summing up the emissions of these various pollutants does not provide a meaningful indicator of the combined air quality impact of these emission changes. Instead, a more appropriate indicator is the percentage change in emissions for each emitted pollutant, weighted according to the air quality impact for each.

For this purpose, EPA examined speciation data available from its Air Explorer Web site for 2007-2009 for the Indianapolis area. These data suggest that PM_2.5 in the Indianapolis area consists of approximately 47 percent sulfate, 12 percent nitrate, 34 percent organic particulate, 4 percent miscellaneous inorganic particulate (sometime labeled “crustal particles”), and 3 percent other types of particulate matter.

EPA used a conservative approach that assumes that the full ambient concentration of organic particulate matter plus miscellaneous inorganic particulate matter will vary in accordance with changes in total nonattainment area emissions of directly emitted PM_2.5. This analysis thus assumes that the entirety of this component of ambient PM_2.5 will increase by the 5 percent that Indiana's maintenance plan projects that directly emitted PM_2.5 emissions will increase from 2008 to 2015, the year with the greatest estimated emissions of direct PM_2.5. In this analysis, the baseline concentration is assumed to be 14.3 μg/m³ (the design value for the 2007-2009 time period), of which directly emitted PM_2.5 is estimated to comprise 38 percent (34 plus 4), or 5.4 μg/m³. EPA's assessment assumes that the 5 percent increase in direct PM_2.5 emissions from 2008 to 2015, the year with the highest projected levels of directly emitted PM_2.5, will cause a corresponding increase in ambient concentrations of PM_2.5, which would suggest an increase in the concentration of this component by 0.3 μg/m³. However, EPA believes that this potential increase will be fully compensated by much greater decreases in sulfate and nitrate concentrations.

Determining the precise levels of decrease in sulfate and nitrate concentrations is a complex task requiring consideration of emission reductions not only in the Indianapolis area but also in many other parts of the Eastern United States. Nevertheless, sulfates and nitrates comprise 47 percent and 12 percent of the PM_2.5 in the Indianapolis area, respectively, and both are projected to decrease by 26 percent over this same 2008-2015 time period. Further, as shown in table 10 below, emissions of sulfates and nitrates from power plants in states impacting the Indianapolis area are projected to decrease by 66 percent and 47 percent, respectively. Therefore, the 0.3 μg/m³ increase associated with directly emitted PM_2.5 would be expected to be more than offset by decreases in monitored concentrations associated with decreases in sulfates and nitrates. That is, EPA expects that the temporary minimal increase in direct emissions of PM_2.5 in the Indianapolis area will not prevent the area from maintaining the standard.

Because the PM_2.5 concentrations in the Indianapolis area are significantly impacted by the transport of sulfates and nitrates, the area's air quality is strongly affected by regulation of SO₂ and NO_X emissions from power plants. Table 10, below, compares statewide EGU emissions data for 2008 and 2014. Emissions for 2008 reflect actual emissions data compiled by EPA's Clean Air Markets Division reflecting reductions implemented under CAIR. 2014 emissions reflect EPA's projections of emissions expected under the CSAPR as shown at http://epa.gov/​crossstaterule/​pdfs/​EmissionsSummaries.xlsx.

Table 10—Comparison of 2008 and 2014 Statewide EGU NO_X and SO₂ Emissions (tpy) for States Impacting the Indianapolis Area

State	NOX			SO2
	2008	2014	Net change 2002-2014	2008	2014	Net change 2002-2014
Alabama	112,625	69,192	−43,433	448,248	173,566	−274,682
Illinois	119,930	49,162	−70,768	257,357	132,647	−124,710
Indiana	190,092	110,740	−79,352	565,459	195,046	−370,413
Iowa	49,023	42,231	−6,792	127,847	83,827	−44,020
Kentucky	157,903	76,088	−81,815	344,356	116,927	−227,429
Michigan	107,624	60,907	−46,717	326,501	162,632	−163,869
Missouri	88,742	52,103	−36,639	258,269	186,899	−71,370
Ohio	235,049	89,753	−145,296	709,444	178,975	−530,469
Pennsylvania	183,658	118,981	−64,677	831,915	125,545	−706,370
Tennessee	85,641	20,512	−65,129	208,069	64,721	−143,348
West Virginia	99,484	53,975	−45,509	301,574	84,344	−217,230
Wisconsin	47,794	33,537	−14,257	129,694	50,137	−79,557
Total	1,477,564	777,181	−700,383	4,508,733	1,555,266	−2,953,467

Table 10 shows that NO_X emissions from EGUs are projected to decrease by 700,383 tpy from 2008 to 2014 in states impacting the Indianapolis area. Over that same time period, SO₂ emissions from EGUs are projected to decrease by 2,953,467 tpy in states impacting the Indianapolis area.

Based on the information summarized above, Indiana has adequately demonstrated maintenance of the PM_2.5 standard in this area for a period extending in excess of ten years from the date that EPA may be expected to complete rulemaking on the State's redesignation request.

d. Monitoring Network

Indiana currently operates three monitors for purposes of determining attainment with the 1997 annual PM_2.5 standard in the Indianapolis area. Indiana has committed to continue to operate and maintain these monitors and will consult with EPA prior to making any changes to the existing monitoring network. IDEM remains obligated to continue to quality assure monitoring data in accordance with 40 CFR part 58 and enter all data into the AQS in accordance with Federal guidelines.

e. Verification of Continued Attainment

Continued attainment of the annual PM_2.5 NAAQS in the Indianapolis area depends, in part, on the State's efforts toward tracking indicators of continued attainment during the maintenance period. Indiana's plan for verifying continued attainment of the annual PM_2.5 standard in the Indianapolis area consists of continued ambient PM_2.5 monitoring in accordance with the requirements of 40 CFR part 58. IDEM will also continue to develop and submit periodic emission inventories as required by the Federal Consolidated Emissions Reporting Rule (codified at 40 CFR 51 Subpart A) to track future levels of emissions.

f. Contingency Plan

The contingency plan provisions are designed to promptly correct or prevent a violation of the NAAQS that might occur after redesignation of an area to attainment. Section 175A of the CAA requires that a maintenance plan include such contingency measures as EPA deems necessary to ensure that the state will promptly correct a violation of the NAAQS that occurs after redesignation. The maintenance plan should identify the contingency measures to be adopted, a schedule and procedure for adoption and implementation of the contingency measures, and a time limit for action by the state. The state should also identify specific indicators to be used to determine when the contingency measures need to be adopted and implemented. The maintenance plan must include a requirement that the state will implement all measures with respect to control of the pollutant(s) that were contained in the SIP before redesignation of the area to attainment. See section 175A(d) of the CAA.

As required by section 175A of the CAA, Indiana has adopted a contingency plan for the Indianapolis area to address possible future annual PM_2.5 air quality problems. Under Indiana's plan, if a violation of the 1997 annual PM_2.5 standard occurs, Indiana will implement an “Action Level Response” to evaluate what measures are warranted to address the violation, committing to implement one or more measures from a list of candidate measures given in the plan. Indiana's candidate contingency measures include the following:

i. Alternative fuel and diesel retrofit programs for fleet vehicle operations;

ii. NO_X or SO₂ controls on new minor sources;

iii. Wood stove change out program;

iv. Idle restrictions;

v. Broader geographic applicability of existing measures; and

vi. One or more transportation control measures sufficient to achieve at least a 0.5 percent reduction in actual area wide precursor emissions.

Under Indiana's plan, control measures are to be adopted and implemented within 18 months from the end of the year in which air quality triggering the Action Level Response occurs. Indiana further commits to conduct ongoing review of its data, and if monitored concentrations or emissions are trending upward, Indiana commits to take appropriate steps to avoid a violation if possible. EPA believes that Indiana's contingency plan satisfies the pertinent requirements of section 175A(d).

g. Provisions for Future Updates of the Annual PM_2.5 Maintenance Plan

As required by section 175A(b) of the CAA, IDEM commits to submit to EPA an updated maintenance plan eight years after redesignation of the Indianapolis area to attainment of the 1997 annual PM_2.5 standard to cover an additional ten-year period beyond the initial ten-year maintenance period. As required by section 175A of the CAA, Indiana has committed to retain the control measures contained in the SIP prior to redesignation, and to submit to EPA for approval as a SIP revision, any changes to its rules or emission limits applicable to SO₂, NO_X, or direct PM_2.5 sources as required for maintenance of the annual PM_2.5 standard in the Indianapolis area.

EPA has concluded that the maintenance plan adequately addresses the five basic components of a maintenance plan: attainment inventory, maintenance demonstration, monitoring network, verification of continued attainment, and a contingency plan. Thus EPA is finding that the maintenance plan SIP revision submitted by Indiana for the Indianapolis area meets the requirements of section 175A of the CAA.

B. Adequacy of Indiana's MVEBs

1. How are MVEBs developed and what are the MVEBs for the Indianapolis area?

Under the CAA, states are required to submit, at various times, control strategy SIP revisions and maintenance plans for PM_2.5 nonattainment areas and for areas seeking redesignations to attainment of the PM_2.5 standard. These emission control strategy SIP revisions (e.g., RFP and attainment demonstration SIP revisions) and maintenance plans create MVEBs based on on-road mobile source emissions for criteria pollutants and/or their precursors to address pollution from on-road transportation sources. The MVEBs are the portions of the total allowable emissions that are allocated to highway and transit vehicle use that, together with emissions from other sources in the area, will provide for attainment, RFP or maintenance, as applicable.

Under 40 CFR part 93, a MVEB for an area seeking a redesignation to attainment is established for the last year of the maintenance plan. The MVEB serves as a ceiling on emissions from an area's planned transportation system. The MVEB concept is further explained in the preamble to the November 24, 1993, transportation conformity rule (58 FR 62188).

Under section 176(c) of the CAA, transportation plans and transportation improvement programs (TIPs) must be evaluated to determine if they conform with the area's SIP. Conformity to the SIP means that transportation activities will not cause new air quality violations, worsen existing air quality violations, or delay timely attainment of the NAAQS or any required interim milestone. If a transportation plan or TIP does not conform, most new transportation projects that would expand the capacity of roadways cannot go forward. Regulations at 40 CFR part 93 set forth EPA policy, criteria, and procedures for demonstrating and assuring conformity of such transportation activities to a SIP.

When reviewing SIP revisions containing MVEBs, including attainment strategies, rate-of-progress plans, and maintenance plans, EPA must affirmatively find “adequate” or approve for use in determining transportation conformity before the MVEBs can be used. Once EPA affirmatively approves or finds the submitted MVEBs to be adequate for transportation conformity purposes, the MVEBs must be used by state and Federal agencies in determining whether transportation plans and TIPs conform to the SIP as required by section 176(c) of the CAA. EPA's substantive criteria for determining the adequacy of MVEBs are set out in 40 CFR 93.118(e)(4). Additionally, to approve a motor vehicle emissions budget EPA must complete a thorough review of the SIP, in this case the PM_2.5 maintenance plan, and conclude that the SIP will achieve its overall purpose, in this case providing for maintenance of the 1997 annual PM_2.5 standard.

EPA's process for determining adequacy of a MVEB consists of three basic steps: (1) Providing public notification of a SIP submission; (2) providing the public the opportunity to comment on the MVEB during a public comment period; and, (3) EPA taking action on the MVEB. The process for determining the adequacy of submitted SIP MVEBs is codified at 40 CFR 93.118.

The maintenance plan submitted by Indiana for the Indianapolis area contains new primary PM_2.5 and NO_X MVEBs for the area for the years 2015 and 2025. IDEM has determined the 2015 MVEBs for the Indianapolis area to be 353.40 tpy for primary PM_2.5 and 14,956.79 tpy for NO_X. IDEM has determined the 2025 MVEBs for the Indianapolis area to be 317.86 tpy for primary PM_2.5 and 8,839.80 tpy for NO_X. These MVEBs exceed the on-road mobile source primary PM_2.5 and NO_X emissions projected by IDEM for 2015 and 2025, as summarized in table 11 below. IDEM decided to include “safety margins” as provided for in 40 CFR 93.124(a) (described further below) of 63.73 tpy and 57.32 tpy for primary PM_2.5 and 2,697.13 tpy and 1,594.06 tpy for NO_X in the 2015 and 2025 MVEBs, respectively, to provide for on-road mobile source growth. Indiana did not provide emission budgets for SO₂, VOCs, and ammonia because it concluded, consistent with EPA's presumptions regarding these precursors, that emissions of these precursors from motor vehicles are not significant contributors to the area's PM_2.5 air quality problem.

The availability of the SIP submission with these 2015 and 2025 MVEBs was announced for public comment on EPA's Adequacy Web site on July 19, 2011, at: http://www.epa.gov/​otaq/​stateresources/​transconf/​currsips.htm. The EPA public comment period on adequacy of the 2015 and 2025 MVEBs for the Indianapolis area closed on August 18, 2011. No adverse comments on the submittal were received during the adequacy comment period.

Table 11—On-Road Mobile Source Emissions Estimates and Budgets

[tpy]

	NOX		PM2.5
	Emissions estimate	Budget	Emissions estimate	Budget
2008	21,494.74		403.67
2015	12,259.66	14,956.79	289.67	353.40
2025	7,245.74	8,839.80	260.54	317.86

In the Indianapolis area, the motor vehicle budgets and motor vehicle emission projections for both NO_X and primary PM_2.5 are lower than base year levels, but the overall emissions of primary PM_2.5 summed across all source types is projected to increase in 2015. This requires further examination of the question of whether an increase in overall primary PM_2.5 emissions by the amounts requested by Indiana as safety margins would still provide for maintenance of the PM_2.5 standard.

The discussion of the maintenance plan above describes EPA's rationale for believing that the impact of the projected increase in total primary PM_2.5 emissions in 2015 will be more than compensated for by the projected decreases in overall emissions of SO₂ and NO_X. EPA examined whether the same conclusion would apply if the Indianapolis area used the entire safety margin in 2015, i.e., if mobile source PM_2.5 emissions reached the full level of the PM_2.5 MVEB for 2015. Assuming mobile source PM_2.5 emissions of 353.40 tpy, the level of the 2015 PM_2.5 MVEB, total direct PM_2.5 emissions in 2015 are estimated to be 4,363.51, a 6 percent increase over 2008 PM_2.5 emissions. Applying a 6 percent increase to 5.4 μg/m³, the baseline ambient PM_2.5 concentration attributable to direct PM_2.5 emissions, the expected impact of the overall PM_2.5 emissions increase still rounds to 0.3 μg/m³, which EPA again holds is more than compensated for by the decrease in sulfate and nitrate concentrations resulting from reductions in SO₂ and NO_X emissions, as explained above. Therefore, EPA concludes that the submitted budgets, including the safety margins, provide for a quantity of mobile source emissions that would be expected to maintain the PM_2.5 standard.

EPA has reviewed the submitted budgets for 2015 and 2025 including the added safety margins using the conformity rule's adequacy criteria found at 40 CFR 93.118(e)(4) and the conformity rule's requirements for safety margins found at 40 CFR 93.124(a). EPA has also completed a thorough review of the entire maintenance plan for the Indianapolis area. Based on the results of this review of the budgets and the maintenance plan EPA is approving the 2015 and 2025 direct PM_2.5 and NO_X budgets including the requested safety margins for the Indianapolis area. Additionally, EPA, through this rulemaking, has found the submitted budgets to be adequate for use to determine transportation conformity in the Indianapolis area, because EPA has determined that the area can maintain attainment of the 1997 annual PM_2.5 NAAQS for the relevant maintenance period with on-road mobile source emissions at the levels of the MVEBs. These budgets must be used in conformity determinations made on or after the effective date of this direct final rulemaking, November 28, 2011. (40 CFR 93.118(f)(iii))

The budgets that Indiana submitted were calculated using the MOBILE6.2 motor vehicle emissions model. EPA is approving the conformity budgets calculated using this model because this model was the most current model available at the time Indiana was performing its analysis. As discussed in section IV.A.4.c. above, EPA has issued an updated motor vehicle emissions model known as MOVES. In its announcement of this model, EPA established a two-year grace period that allows for continued use of MOBILE6.2 in transportation conformity determinations for transportation plans and TIPs (extending to March 2, 2012), after which states and metropolitan planning organizations (MPOs) (other than California) must use MOVES for transportation plan and TIP conformity determinations. (See 75 FR 9411, March 2, 2010.)

Additional information on the use of MOVES in SIPs and conformity determinations can be found in the December 2009 MOVES Guidance. During the conformity grace period, the State and MPO should use the interagency consultation process to examine how MOVES will impact their future transportation plan and TIP conformity determinations, including regional emissions analyses. For example, an increase in emission estimates due to the use of MOVES may affect an area's ability to demonstrate conformity for its transportation plan and/or TIP. Therefore, State and local planners should carefully consider whether the SIP and motor vehicle emissions budget(s), transportation plans, and TIPs should be revised with MOVES before the end of the conformity grace period, since doing so may be necessary to ensure conformity determinations in the future.

We would expect that states and MPOs would work closely with EPA and the local Federal Highway Administration and Federal Transit Administration offices to determine an appropriate course of action to address this type of situation if it is expected to occur. If Indiana chooses to revise the Indianapolis maintenance plan, it should consult Question 7 of the December 2009 MOVES guidance for information on requirements related to such revisions.

2. What is a safety margin?

A “safety margin” is the difference between the attainment level of emissions (from all sources) and the projected level of emissions (from all sources) in the maintenance plan. As shown in table 7, NO_X emissions in the Indianapolis area are projected to have safety margins of 13,429.68 tpy and 22,378.72 tpy in 2015 and 2025, respectively (the difference between the attainment year, 2008, emissions and the projected 2015 and 2025 emissions for all sources in the Indianapolis area). Table 8 shows direct PM_2.5 emissions in the Indianapolis area are projected to have a safety margin of 127.81 tpy in 2025. Table 9 shows SO₂ emissions in the Indianapolis area are projected to have safety margins of 11,114.53 tpy and 11,301.19 tpy in 2015 and 2025, respectively. Even if emissions reached the full level of the safety margin, the area would still demonstrate maintenance since emission levels would equal those in the attainment year.

The transportation conformity rule allows areas to allocate all or a portion of a “safety margin” to the area's motor vehicle emissions budgets. (40 CFR 92.124(a)) The MVEBs requested by IDEM contain NO_X safety margins for mobile sources in 2015 and 2025 and PM_2.5 safety margins for mobile sources in 2025 smaller than the allowable safety margins reflected in the total emissions for the Indianapolis area. The State is not requesting allocation to the MVEBs of the entire available safety margins reflected in the demonstration of maintenance. Therefore, even though the State has submitted MVEBs that exceed the projected on-road mobile source emissions for 2015 and 2025 contained in the demonstration of maintenance, the increase in on-road mobile source emissions that can be considered for transportation conformity purposes is well within the safety margins of the PM_2.5 maintenance demonstration. Further, once allocated to mobile sources, these safety margins will not be available for use by other sources.

Projected direct PM_2.5 emissions in 2015 exceed 2008 emission levels, and IDEM has included a mobile safety margin of 63.73 tpy in the 2015 PM_2.5 MVEB. However, as discussed above, EPA holds that the impact of the PM_2.5 emissions increase is more than compensated by decreases in sulfate and nitrate concentrations resulting from reductions in SO₂ and NO_X emissions. Therefore, EPA concludes that the requested budgets, including the requested safety margins, provide for a quantity of mobile source emissions that would be expected to maintain the PM_2.5 standard.

C. 2006 Comprehensive Emissions Inventory

As discussed above in section IV.A.2.a.ii., section 172(c)(3) of the CAA requires areas to submit a comprehensive, accurate and current emissions inventory. IDEM submitted a 2006 base year emissions inventory that meets this requirement. Emissions contained in the submittal cover the general source categories of point sources, area sources, on-road mobile sources, and nonroad mobile sources.

For the point source sector, EGU SO₂ and NO_X emissions were derived from EPA's Clean Air Market's database. All other point source emissions were obtained from Indiana's source facility emissions reporting.

Area source emissions were extrapolated from Indiana's 2005 periodic emissions inventory. Source growth factors were supplied by LADCO.

Nonroad mobile source emissions were extrapolated from nonroad mobile source emissions reported in EPA's 2005 NEI. Contractors were employed by LADCO to estimate emissions for commercial marine vessels and railroads, which were not adequately addressed in EPA's 2005 NEI.

On-road mobile source emissions were calculated using EPA's mobile source emission factor model, MOBILE6.2.

Note that all emissions discussed below were documented in appendices B through E of Indiana's May 31, 2011, redesignation request submittal. EPA has reviewed Indiana's documentation of the emissions inventory techniques and data sources used for the derivation of the 2006 emissions estimates and has found that Indiana has thoroughly documented the derivation of these emissions inventories.

In the May 31, 2011, submittal, IDEM states that the 2006 emissions inventory (and the 2008 attainment year emissions inventory) are currently the most complete emissions inventories for PM_2.5 and PM_2.5 precursors in the Indianapolis area. We also conclude that the 2006 emissions inventory is complete and is as accurate as possible given the input data available to the State. Therefore, we are approving the 2006 PM_2.5 emissions inventory for the Indianapolis area as meeting the requirement of section 172(c)(3) of the CAA.

Table 12—Indianapolis Area NO_X, Direct PM_2.5, and SO₂ Emissions (tpy) for 2006 by Source Sector

Sector	NOX	Direct PM2.5	SO2
Point	6,035.88	843.43	3,919.71
EGU	7,820.39	763.74	57,451.29
Area	4,841.01	85.70	1,820.79
Nonroad	12,261.91	901.58	1,146.90
On-road	22,734.38	416.63	842.20
Total	53,693.57	3,011.08	65,180.89

V. Summary of Actions

EPA is making a determination that the Indianapolis area is attaining the 1997 annual PM_2.5 standard and that the area has met the requirements for redesignation under section 107(d)(3)(E) of the CAA. EPA is thus approving the request from IDEM to change the legal designation of the Indianapolis area from nonattainment to attainment for the 1997 annual PM_2.5 NAAQS. EPA is approving Indiana's PM_2.5 maintenance plan for the Indianapolis area as a revision to the Indiana SIP because the plan meets the requirements of section 175A of the CAA. EPA is approving 2006 emissions inventories for primary PM_2.5, NO_X, and SO₂, documented in Indiana's May 31, 2011, PM_2.5 redesignation request supplemental submittal as satisfying the requirement in section 172(c)(3) of the CAA for a comprehensive, current emission inventory. Finally, EPA finds adequate and is approving 2015 and 2025 primary PM_2.5 and NO_X MVEBs for the Indianapolis area. These MVEBs will be used in future transportation conformity analyses for the area.

VI. Statutory and Executive Order Reviews

Under the CAA, redesignation of an area to attainment and the accompanying approval of a maintenance plan under section 107(d)(3)(E) are actions that affect the status of a geographical area and do not impose any additional regulatory requirements on sources beyond those imposed by state law. A redesignation to attainment does not in and of itself create any new requirements, but rather results in the applicability of requirements contained in the CAA for areas that have been redesignated to attainment. Moreover, the Administrator is required to approve a SIP submission that complies with the provisions of the CAA and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, EPA's role is to approve state choices, provided that they meet the criteria of the CAA. Accordingly, this action merely approves state law as meeting Federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, these actions:

• Are 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);
• Do not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
• Are 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.);
• Do 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);
• Do not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);
• Are not economically significant regulatory actions based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);
• Are not significant regulatory actions subject to Executive Order 13211 (66 FR 28355, May 22, 2001);
• Are 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
• Do 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 rule does not have tribal implications as specified by Executive Order 13175 (65 FR 67249, November 9, 2000), because the SIP is not approved to apply in Indian country located in the state, and EPA notes that it will not impose substantial direct costs on tribal governments or preempt tribal law.

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

Under section 307(b)(1) of the CAA, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by November 28, 2011. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of these actions for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such rule or action. Parties with objections to this direct final rule are encouraged to file a comment in response to the parallel notice of proposed rulemaking for this action published in the proposed rules section of today's Federal Register, rather than file an immediate petition for judicial review of this direct final rule, so that EPA can withdraw these direct final rules and address the comment in the proposed rulemaking. These actions may not be challenged later in proceedings to enforce their requirements. (See section 307(b)(2).)

List of Subjects in 40 CFR Part 52

• Environmental protection
• Air pollution control
• Incorporation by reference
• Intergovernmental relations
• Particulate matter

Dated: September 12, 2011.

Susan Hedman,

Regional Administrator, Region 5.

40 CFR parts 52 and 81 are amended as follows:

PART 52—[AMENDED]

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

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

Subpart P—Indiana

2. Section 52.776 is amended by adding paragraphs (v)(2) and (w)(2) to read as follows:

§ 52.776

Control strategy: Particulate matter.

* * * * *

(v) * * *

(2) The Indianapolis area (Hamilton, Hendricks, Johnson, Marion and Morgan Counties), as submitted on October 20, 2009, and supplemented it on May 31, 2011. The maintenance plan establishes 2015 motor vehicle emissions budgets for the Indianapolis area of 353.40 tpy for primary PM_2.5 and 14,956.79 tpy for NO_X and 2025 motor vehicle emissions budgets of 317.86 tpy for primary PM_2.5 and 8,839.80 tpy for NO_X.

(w) * * *

(2) Indiana's 2006 NO_X, directly emitted PM_2.5, and SO₂ emissions inventory satisfies the emission inventory requirements of section 172(c)(3) of the Clean Air Act for the Indianapolis area.

PART 81—[AMENDED]

3. The authority citation for part 81 continues to read as follows:

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

4. Section 81.315 is amended by revising the entry for Indianapolis, IN in the table entitled “Indiana PM _2.5 (Annual NAAQS)” to read as follows:

§ 81.315

Indiana.

* * * * *

Indiana PM_2.5

[Annual NAAQS]

Designated area	Designation a
	Date 1	Type
*         *         *         *         *         *         *
Indianapolis, IN:	11/28/11	Attainment.
Hamilton County
Hendricks County
Johnson County
Marion County
Morgan County
*         *         *         *         *         *         *
a Includes Indian Country located in each county or area, except as otherwise specified.
1 This date is 90 days after January 5, 2005, unless otherwise noted.

* * * * *

Footnotes

1.  Fine particulates directly emitted by sources and not formed in a secondary manner through chemical reactions or other processes in the atmosphere.

2.  NO_X and SO₂ are precursors for fine particulates formed through chemical reactions and other related processes in the atmosphere.

3.  Periodic emission inventories are derived by states every three years and reported to EPA. These periodic emission inventories are required by the Federal Consolidated Emissions Reporting Rule, codified at 40 CFR Subpart A. EPA revised these and other emission reporting requirements in a final rule published on December 17, 2008, at 73 FR 76539.

4.  MOVES2010a is EPA's most recent model for estimating on-road mobile source emissions. MOVES was officially released for use in SIPs and regional transportation conformity determinations on March 2, 2010, at 75 FR 9411.