2024-07701. Air Plan Approval; North Carolina; Revision to Approved Motor Vehicle Emissions Budgets

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Proposed rule.

SUMMARY:

The Environmental Protection Agency (EPA) is proposing to approve a revision to the North Carolina State Implementation Plan (SIP), submitted by the North Carolina Department of Environmental Quality (NCDEQ), Division of Air Quality, on December 19, 2022. The revision seeks to update the 2026 on-road and nonroad emissions inventories and safety margins, allocate a portion of the newly available 2026 safety margins in the 2008 8-hour Ozone Maintenance Plan to the 2026 nitrogen oxides (NO_X) and volatile organic compounds (VOC) motor vehicle emissions budgets (“budgets”) for the North Carolina portion of the Charlotte-Rock Hill, NC-SC bi-state Area (hereinafter referred to as the “North Carolina portion of the Charlotte Maintenance Area”) to accommodate updates from the EPA Motor Vehicle Emissions Simulator (MOVES3) model. The SIP revision also revises the current 2026 budgets based on the MOVES3 updates and recalculates new available safety margins. NCDEQ's December 19, 2022, submission supplements the revised 2008 8-hour Ozone Maintenance Plan submitted by NCDEQ on July 16, 2020, and approved by EPA on August 25, 2021. EPA is proposing to approve North Carolina's December 19, 2022, SIP revision and deem the budgets adequate for transportation conformity purposes because they meet the applicable statutory and regulatory requirements.

DATES:

Comments must be received on or before May 13, 2024.

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-R04-OAR-2023-0057 at www.regulations.gov. Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov. EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. EPA will generally not consider comments or comment contents located outside of the primary submission ( i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit www.epa.gov/​dockets/​commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT:

Dianna Myers, Air Regulatory Management Section, Air Planning and Implementation Branch, Air and Radiation Division, U.S. Environmental Protection Agency, Region 4, 61 Forsyth Street SW, Atlanta, Georgia 30303-8960. The telephone number is [phone]. Ms. Myers can also be reached via electronic mail at [e-mail].

SUPPLEMENTARY INFORMATION:

I. Introduction

EPA is proposing to approve NCDEQ's December 19, 2022, SIP revision which updates the 2026 on-road and nonroad emissions inventories with the latest (at the time of NCDEQ's submission) approved EPA mobile emissions model, MOVES3, allocates a portion of the newly available safety margin, revises the 2026 NO_X and VOC budgets, and recalculates the available safety margins for the North Carolina portion of Charlotte 2008 8-hour Ozone Maintenance Area ^[1] for transportation conformity purposes.

If EPA finalizes this proposed approval, the revised 2026 NO_X and VOC budgets from NCDEQ's December 19, 2022, SIP revision will replace the existing budgets in the State's 2008 8-hour Ozone Maintenance Plan approved on August 25, 2021. See86 FR 47387. If approved, these newly revised 2026 budgets must be used in future transportation conformity analyses for the Area according to the Transportation Conformity Rule. See40 CFR 93.118. Therefore, the August 25, 2021, approved budgets would no longer be applicable for transportation conformity purposes.

In the State's submission, the emissions inventories for point and area sources from NCDEQ's July 16, 2020, SIP revision remain the same. This submission revises the 2026 on-road and nonroad emissions inventories and the NO_X and VOC safety margins using MOVES3. The revision also allocates a portion of the revised available safety margins to the 2026 NO_X and VOC budgets and recalculates new available safety margins. As explained below, EPA is proposing to conclude that North Carolina's December 19, 2022, SIP revision continues to demonstrate maintenance for the Charlotte Maintenance Area.

II. Background

A. SIP Budgets and Transportation Conformity

Under the Clean Air Act (CAA or Act), states are required to submit, at various times, control strategy SIP revisions and maintenance plans for nonattainment and maintenance areas for a given NAAQS. These emission control strategy SIP revisions ( e.g., reasonable further progress and attainment demonstration SIP revisions) and maintenance plans include budgets of on-road mobile source emissions for criteria pollutants and/or their precursors to address pollution from cars, trucks, and other on-road vehicles. The budgets are the portion of the total allowable emissions that are allocated to on-road-vehicle use that, together with emissions from other sources in the area, will provide for attainment or maintenance. The budgets serve as a ceiling on emissions from an area's planned transportation system.

Under section 176(c) of the CAA, transportation plans, transportation improvement programs (TIPs), and transportation projects must “conform” to ( i.e., be consistent with) the SIP before they can be adopted or approved. 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 an interim milestone. The transportation conformity regulations can be found at 40 CFR parts 51 and 93.

Before budgets may be used in conformity determinations, EPA must affirmatively find the budgets adequate. However, adequate budgets do not supersede approved budgets for the same CAA purpose. If the submitted SIP budgets are meant to replace budgets for the same CAA purpose and year(s) addressed by a previously approved SIP revision, as is the case with this SIP revision, EPA may approve the revised SIP and budgets and also affirm that the budgets are adequate at the same time. Once EPA approves the submitted budgets, the revised budgets must be used by State and Federal agencies in determining whether transportation activities conform to the SIP as required by section 176(c) of the CAA. EPA's substantive criteria for determining the adequacy of budgets are set out in 40 CFR 93.118(e)(4).

B. Prior Approval of Budgets

Effective July 20, 2012, EPA designated the Charlotte-Rock Hill, NC-SC Area as Marginal nonattainment for the 2008 8-hour ozone NAAQS. The North Carolina portion of the Charlotte 2008 Maintenance Area includes Mecklenburg County in its entirety and portions of Cabarrus, Gaston, Iredell, Lincoln, Rowan, and Union Counties. The Charlotte Maintenance Area also includes a portion of York County located in Rock Hill, South Carolina. See77 FR 30088 (May 21, 2012). The North Carolina portion of the Charlotte Maintenance Area is comprised of three metropolitan planning organizations (MPOs): the Charlotte Regional Transportation Planning Organization (CRTPO) which covers Iredell, Mecklenburg, and Union Counties; the Cabarrus-Rowan Metropolitan Planning Organization (CRMPO) which covers Cabarrus and Rowan Counties; and the Gaston-Cleveland-Lincoln Metropolitan Planning Organization (GCLMPO) which covers Gaston, Cleveland, and Lincoln Counties. Although Cleveland County is included in the GCLMPO planning boundary, it was not included in the North Carolina portion of the Charlotte Maintenance Area. Each MPO has its own budget, which is referred to as a “sub-area budget.” The York County, South Carolina, portion of this maintenance area has a separate MPO and budgets. The South Carolina portion of the maintenance area implements transportation conformity independent of the North Carolina portion.

EPA approved the redesignation request and maintenance plan for North Carolina's portion of the Charlotte 2008 8-hour ozone Area on July 28, 2015 (80 FR 44873) with 2014 and 2026 NO_X and VOC sub-area budgets. On August 17, 2015 (80 FR 49164), EPA approved North Carolina's requested relaxation of the Federal Reid Vapor Pressure (RVP) requirement from 7.8 pounds per square inch (psi) to 9.0 psi. See80 FR 44868 (approving the CAA section 110(l) non-interference demonstration that relaxing the Federal RVP requirement from 7.8 psi to 9.0 psi in Mecklenburg and Gaston Counties would not interfere with maintenance of the NAAQS in the Area and approving a revision to the 2026 NO_X and VOC sub-area budgets for Mecklenburg and Gaston Counties only).

On July 25, 2018, NCDEQ submitted a revision to the Charlotte 2008 8-hour ozone maintenance plan to update the emissions forecast and budgets for 2026 to account for the small increase in NO_X and VOC emissions associated with the change in vehicle model year coverage due to changes in the State of North Carolina's inspection and maintenance (I/M) program. On September 11, 2019 (84 FR 47889), EPA approved NCDEQ's July 25, 2018, SIP revision related to North Carolina's I/M Program. The September 11, 2019, SIP approval updated the on-road mobile source inventory and revised the 2026 sub-area VOC and NO_X budgets for Cabarrus and Rowan Counties. The revised 2026 budgets became effective on October 11, 2019.

Subsequently, on August 25, 2021, EPA approved NCDEQ's July 16, 2020, SIP revision which allocated a portion of the available safety margin to the 2026 sub-area NO_X and VOC budgets to accommodate updates to the travel demand model used to calculate vehicle miles traveled in the Area. See86 FR 47387. The revision to the 2026 sub-area budgets became effective on September 24, 2021.

C. MOVES Emissions Model

The MOVES model is designed by EPA to estimate air pollution emissions from mobile sources. MOVES can be used to estimate exhaust and evaporative emissions as well as brake and tire wear emissions from all types of on-road vehicles for any part of the country, except California.^[2] On January 7, 2021 (86 FR 1106), EPA announced the availability of MOVES3 for official purposes outside of California. At that time, MOVES3 was the latest state of-the art upgrade to EPA's modeling tools for estimating emissions from cars, trucks, buses, and motorcycles based on the latest data and regulations and was available for use in SIPs and transportation conformity analyses outside of California. The notice of availability started a two-year grace period ^[3] after which MOVES3 was required to be used in new regional-emissions and hot-spot analyses for transportation conformity determinations outside of California.

On September 12, 2023 (88 FR 62567), EPA announced the availability of MOVES4 for official purposes outside of California. MOVES4 is the latest state-of-the art upgrade to EPA's modeling tools for estimating emissions from cars, trucks, buses, and motorcycles based on the latest data and regulations. MOVES4 is available for use in SIPs and transportation conformity analyses outside of California. The notice of availability started a two-year grace period ^[4] after which MOVES4 is required to be used in new regional-emissions and hot-spot analyses for transportation conformity determinations outside of California. States should use the latest version of MOVES that is available at the time that a SIP is developed. However, state and local agencies that have already completed significant work on a SIP with a version of MOVES3 ( e.g., attainment modeling has already been completed with MOVES3) may continue to rely on this earlier version of MOVES. It would be unreasonable to require states to revise such SIPs using MOVES4 since significant work has already occurred based on the latest information available at the time the SIP was developed, and EPA intends to act on these SIPs in a timely manner. North Carolina developed and submitted the SIP revision that is the subject of this proposed rulemaking before the MOVES3 grace period ended and before MOVES4 was available. Therefore, use of MOVES3 is appropriate here.

III. EPA's Analysis of North Carolina's Submittal

EPA's analysis involves an emissions comparison between the current SIP-approved on-road and nonroad emissions inventory and budgets and the revised inventories and budgets that North Carolina has requested that EPA approve in the December 19, 2022, SIP submittal. Section III.A. provides information regarding the current SIP-approved and revised inventories and safety margins, while sections III.B. and III.C. contain information and analysis regarding the proposed percentages and revisions to the 2026 budgets and new safety margins, respectively. Section III.D. contains EPA's analysis of the adequacy of North Carolina's revised budgets pursuant to 40 CFR 93.118(e)(4).

As discussed further below, EPA's analysis of North Carolina's December 19, 2022, SIP submittal indicates that maintenance will continue to be demonstrated after allocation of a portion of the safety margin to the budgets because the total level of emissions from all source categories remains equal to or less than the attainment level of emissions. Thus, EPA is proposing to approve North Carolina's December 19, 2022, SIP submittal.

A. Maintenance Demonstration and Emissions Inventory

This section contains information regarding the previous and current SIP-approved budgets and inventories. The point and area source inventories are provided for illustrative purposes only since, in this action, EPA is not proposing any changes to the September 11, 2019, SIP point and area source inventories.^[5] The 2026 on-road and nonroad ^[6] emissions inventories were modeled using MOVES3, which, as discussed in section II.C. above, is based on the latest modeling assumptions and input data available at the time it was released. The on-road mobile source emissions for all other years were unchanged as compared to the currently approved version of the maintenance plan.

As discussed above, EPA originally approved NCDEQ's 2008 8-hour ozone maintenance SIP for the North Carolina portion of the Charlotte Maintenance Area on July 28, 2015, with the following inventories for NO_X and VOC emissions: base year actual emissions inventories for 2014; projected, future, and interim year inventories for 2015, 2018, and 2022; and projected final year emission inventory for 2026. On September 11, 2019 (84 FR 47889), EPA approved NCDEQ's July 25, 2018, SIP, which revised the budgets and the inventories. EPA subsequently approved NCDEQ's July 16, 2020, SIP revision (86 FR 47387), which revised the sub-area budgets. These remain the current SIP-approved budgets and inventories. See tables 1 through 3, below.

Maintenance for the Charlotte Maintenance Area is demonstrated when the emissions in the final year of the maintenance plan (“maintenance year”) are less than the emissions in the baseline attainment year. In the current SIP-approved inventories, the baseline year is 2014 and the maintenance year is 2026. See80 FR 29250.

Table 1—Current Total Man-Made NO _X Emissions for North Carolina Portion of the Charlotte Maintenance Area

[Tons/day]

County	2014	2015	2018	2022	2026
Cabarrus *	11.49	10.73	6.78	5.44	4.44
Gaston *	27.89	27.62	12.03	6.41	7.87
Iredell *	6.86	6.49	5.41	4.68	4.16
Lincoln *	4.36	4.71	6.41	4.29	2.34
Mecklenburg	56.71	52.97	39.16	33.52	31.33
Rowan *	11.74	11.31	8.28	7.01	6.10
Union *	11.13	10.36	6.63	5.09	4.05
Total	130.18	124.19	84.69	66.44	60.28
* Emissions for the portion of the county included in the maintenance area.

Table 2—Current Total Man-Made VOC Emissions for North Carolina Portion of the Charlotte Maintenance Area

[Tons/day]

County	2014	2015	2018	2022	2026
Cabarrus *	11.50	11.27	9.51	9.23	9.02
Gaston *	12.96	12.74	11.53	10.94	10.74
Iredell *	6.33	6.22	5.29	5.11	4.97
Lincoln *	6.55	6.47	4.81	4.66	4.51
Mecklenburg	50.10	49.16	45.31	44.47	43.99
Rowan *	12.59	12.38	12.47	12.19	12.32
Union *	13.09	12.85	10.91	10.68	10.45
Total	113.12	111.09	99.82	97.28	95.99
* Emissions for the portion of the county included in the maintenance area.

Table 3—Current Maintenance Demonstration for North Carolina Portion of the Charlotte Maintenance Area

Year	NO X (tons/summer day)	VOC (tons/summer day)
2014	130.18	113.12
2015	124.19	111.09
2018	84.69	99.82
2022	66.44	97.28
2026	60.28	95.99
Reduction in emissions from 2014 to 2026	69.90	17.13

As shown in table 4, the revised NO_X emissions for all years (interim years and maintenance year) are under the baseline of 130.18 tons per summer day (tons/day); in the maintenance year of 2026, emissions are now projected to be 64.75 tons/day. Additionally, as shown in table 5, the revised VOC emissions for all years (interim years and maintenance year) are under the baseline of 113.12 tons/day; in the maintenance year of 2026, emissions are projected to be 94.57 tons/day. The downward trend in revised NO_X and VOC emissions based on the updated MOVES3 2026 NO_X and VOC on-road emissions inventory continues to show maintenance of the NAAQS. See table 6, below.

Table 4—Revised Total Man-Made NO _X Emissions for North Carolina Portion of the Charlotte Maintenance Area

[Tons/day]

County	2014	2015	2018	2022	2026
Cabarrus *	11.49	10.73	6.78	5.44	4.61
Gaston *	27.89	27.62	12.03	6.41	7.87
Iredell *	6.86	6.49	5.41	4.68	4.42
Lincoln *	4.36	4.71	6.41	4.29	2.48
Mecklenburg	56.71	52.97	39.16	33.52	34.95
Rowan *	11.74	11.31	8.28	7.01	6.02
Union *	11.13	10.36	6.63	5.09	4.40
Total	130.18	124.19	84.69	66.44	64.75
* Emissions for the portion of the county included in the maintenance area.

Table 5—Revised Total Man-Made VOC Emissions for North Carolina Portion of the Charlotte Maintenance Area

[Tons/day]

County	2014	2015	2018	2022	2026
Cabarrus *	11.50	11.27	9.51	9.23	8.57
Gaston *	12.96	12.74	11.53	10.94	10.42
Iredell *	6.33	6.22	5.29	5.11	4.88
Lincoln *	6.55	6.47	4.81	4.66	4.63
Mecklenburg	50.10	49.16	45.31	44.47	43.72
Rowan *	12.59	12.38	12.47	12.19	11.96
Union *	13.09	12.85	10.91	10.68	10.39
Total	113.12	111.09	99.82	97.28	94.57
* Emissions for the portion of the county included in the maintenance area.

Table 6—Revised Maintenance Demonstration for North Carolina Portion of the Charlotte Maintenance Area

Year	NO X (tons/day)	VOC (tons/day)
2014	130.18	113.12
2015	124.19	111.09
2018	84.69	99.82
2022	66.44	97.28
2026	64.75	94.57
Reduction in emissions from 2014 to 2026	65.43	18.55

Table 7 provides the revised NO_X and VOC on-road mobile emissions inventory for 2014 (base year) and 2026 (maintenance year) for the 2008 8-hour ozone NAAQS for the North Carolina portion of the Charlotte Maintenance Area. The emissions are expressed in tons/day and in kg/day because the budgets are expressed in kilograms per day (kg/day). The MOVES3 output emissions values were rounded to the nearest kg/day and were divided by 907.1847 to convert them to units of tons/day. The resulting values in tons/day were rounded to two decimal places.

Table 7—Revised On-Road Mobile Source NO _X and VOC Summer Day Emissions in 2014 and 2026 for the North Carolina Portion of the Charlotte Maintenance Area

County	2014 NO X		2014 VOC		2026 NO X		2026 VOC
	tons/day	kg/day	tons/day	kg/day	tons/day	kg/day	tons/day	kg/day
Cabarrus *	6.60	5,989	4.15	3,765	2.43	2,208	1.76	1,600
Gaston *	8.11	7,357	4.61	4,179	2.45	2,224	1.68	1,524
Iredell *	3.36	3,045	1.95	1,768	1.29	1,171	0.86	782
Lincoln *	3.00	2,723	1.91	1,737	1.06	963	0.76	688
Mecklenburg *	26.99	24,488	14.40	13,060	12.08	10,957	7.14	6,476
Rowan *	6.42	5,825	3.76	3,408	1.94	1,757	1.37	1,246
Union *	5.67	5,146	3.54	3,210	2.29	2,074	1.62	1,471
Total	60.15	54,572	34.32	31,127	23.54	21,354	15.19	13,787
* Emissions for the portion of the county included in the maintenance area.

A safety margin is the difference between the attainment level of emissions from all source categories ( i.e., point, area, on-road, and nonroad) (2014 in this case) and the projected level of emissions from all source categories in the maintenance year (2026 in this case). The State may choose to allocate some of the safety margin to the budgets, for transportation conformity purposes, so long as the total level of emissions from all source categories remains equal to or less than the attainment level of emissions. As noted above, North Carolina previously chose to allocate a portion of its NO_X and VOC safety margin to the budgets for the entire North Carolina portion of the Charlotte Maintenance Area for the year 2026. See86 FR 32850 (June 23, 2021) and 86 FR 47387 (August 25, 2021). Tables 8 and 9, below, show the revised MOVES3 safety margins and percentages North Carolina is proposing to allocate to the 2026 NO_X and VOC budgets from the newly calculated safety margins, respectively, in the North Carolina portion of the Charlotte Maintenance Area.

Table 8—Revised Safety Margins for the North Carolina Portion of the Charlotte Maintenance Area

Year	NO X (tons/day)	VOC (tons/day)
2014	N/A	N/A
2015	−5.99	−2.03
2018	−45.49	−13.30
2022	−63.74	−15.84
2026	−65.43	−18.55

B. Revised Budgets

In the December 19, 2022, SIP revision, North Carolina requested that EPA approve revisions to the budgets for the North Carolina portion of the Charlotte 2008 Ozone Maintenance Area by allocating a portion of the remaining safety margin to the budgets.^[7] The budget revisions are proposed to accommodate updates from the mobile emissions model MOVES3. The proposed percentages of the on-road emissions allocated to the 2026 budgets for the North Carolina counties in the Charlotte 2008 Ozone Maintenance Area are listed in the table 9, below.

Table 9—Proposed Percentage of On-Road Emissions Allocated to the 2026 Motor Vehicle Emissions Budget

County	NO X (percent)	VOC 8 (percent)
Cabarrus	65	67
Gaston	60	62
Iredell	62	62
Lincoln	62	62
Mecklenburg	57	57
Rowan	65	67
Union	60	62

Based on the on-road emissions inventory revisions in table 7, the following tables provide the proposed NO_X and VOC sub-area budgets with the proposed safety margin allocations in kg/day for transportation conformity purposes for 2026 (2014 is only shown for illustration because no changes are being made to the budgets for that year).

Table 10—Proposed Cabarrus-Rowan Metropolitan Planning Organization (CRMPO) Budgets in 2014 and 2026

[kg/day] *

	2014 NO X	2014 VOC	2026 NO X	2026 VOC
Base On-road Emissions	11,814	7,173	3,965	2,846
Safety margin allocated to budget			2,578	1,907
Conformity budget	11,814	7,173	6,543	4,753
* Includes the portions of Cabarrus and Rowan Counties in the maintenance area.

Table 11—Proposed Gaston-Cleveland-Lincoln Metropolitan Planning Organization (GCLMPO) Budgets in 2014 and 2026

[kg/day] *

	2014 NO X	2014 VOC	2026 NO X	2026 VOC
Base On-road Emissions	10,079	5,916	3,187	2,212
Safety margin allocated to budget			1,930	1,371
Conformity budget	10,079	5,916	5,117	3,583
* Includes the portions of Gaston and Lincoln Counties in the maintenance area. Although Cleveland County is included in the MPO, it is not included in the Charlotte ozone maintenance area.

Table 12—Proposed Charlotte Regional Transportation Planning Organization (CRTPO)—Rocky River Rural Planning Organization (RRRPO) Budgets in 2014 and 2026

[kg/day] *

	2014 NO X	2014 VOC	2026 NO X	2026 VOC
Base On-road Emissions	32,679	18,038	14,202	8,729
Safety margin allocated to budget			8,215	5,089
Conformity budget	32,679	18,038	22,417	13,818
* Includes all of Mecklenburg County and a portion of Iredell and Union Counties in the maintenance area.

C. Revised Safety Margin

As mentioned above, a safety margin is the difference between the attainment level of emissions from all source categories ( i.e., point, area, on-road, and nonroad) and the projected level of emissions from all source categories. NCDEQ has requested that EPA approve the proposed allocation of some of the available safety margin to the 2026 NO_X and VOC budgets for transportation conformity purposes. The total level of emissions from all source categories remains equal to or less than the attainment level of emissions.

EPA is proposing to approve changes to the budgets that include a proposed allocation of 2,577 and 1,907 kg/day of NO_X and VOC, respectively, for the Cabarrus-Rowan MPO; 1,931 and 1,371 kg/day of NO_X and VOC, respectively, for the Gaston-Cleveland MPO; and 8,215 and 5,089 kg/day of NO_X and VOC, respectively, for the Charlotte Regional TPO. Thus, if EPA's action is finalized as proposed, the amount of the safety margin allocated to the 2026 budgets will be 12,723 kg/day (14.02 tons/day) of NO_X and 8,367 kg/day (9.22 tons/day) of VOC. The proposed new safety margins available for the North Carolina portion of the Charlotte Maintenance Area are listed below.

Table 15—New Safety Margins for the North Carolina Portion of the Charlotte Maintenance Area

Year	NO X (tons/day)	VOC (tons/day)
2014	* N/A	N/A
2015	−5.99	−2.03
2018	−45.49	−13.30
2022	−63.74	−15.84
2026	−51.41	−9.33

D. Adequacy of the Budgets

EPA evaluated NCDEQ's December 19, 2022, SIP revision allocating a portion of the available safety margin to the 2026 MOVES3 based budgets in the revised 2008 8-hour ozone Charlotte maintenance plan for use in determining transportation conformity in the North Carolina portion of the Charlotte Maintenance Area. EPA is proposing this action based on its evaluation of these budgets using the adequacy criteria found in 40 CFR 93.118(e)(4) and its evaluation of NCDEQ's submittal and SIP requirements. EPA is proposing to approve this SIP revision because the SIP continues to serve its intended purpose of maintenance of the 2008 8-hour ozone standard with the newly revised MOVES3 based budgets. EPA is also proposing to deem the budgets adequate for transportation conformity purposes because they meet the adequacy criteria in the conformity rule at 40 CFR 93.118(e)(4). Specifically:

• NCDEQ's SIP was endorsed by the Governor's designee and was subject to a State public hearing ((e)(4)(i));
• Before NCDEQ submitted the SIP revision to EPA, consultation among Federal, State, and local agencies occurred and full documentation was provided to EPA and EPA had no concerns ((e)(4)(ii));
• The budgets are clearly identified and precisely quantified ((e)(4)(iii));
• The budgets, when considered together with all other emissions sources, are consistent with applicable requirements for reasonable further progress, attainment, or maintenance ((e)(4)(iv));
• The budgets are consistent with and clearly related to the emissions inventory and control measures in the SIP revision ((e)(4)(v); and
• The December 19, 2022, SIP revision explains and documents changes to the previous budgets, impacts on point, area, nonroad and on-road source emissions, and changes to established safety margins, and reasons for the changes (including the basis for any changes related to emission factors or vehicle miles traveled) ((e)(4)(vi)).

IV. Proposed Action

EPA is proposing to approve NCDEQ's December 19, 2022, SIP revision, requesting approval of a revision to the Charlotte 2008 8-hr Ozone Maintenance Plan that updates the 2026 on-road and nonroad emissions inventories and safety margins with MOVES3, allocates a portion of the newly available 2026 safety margins. The SIP revision also updates the current 2026 budgets with MOVES3 and recalculates new available safety margins. The revised budgets ensure continued attainment of the 2008 8-hour ozone NAAQS through the maintenance year 2026. In addition, EPA is proposing to deem the budgets adequate for transportation conformity purposes because the budgets meet the adequacy criteria in the conformity rule at 40 CFR 93.118(e)(4). If approved, the newly revised MOVES3 2026 budgets for NO_X and VOC identified in tables 10 through 12 will be used by the MPOs in future transportation conformity determinations. The remaining safety margins are 51.41 tons/day and 9.33 tons/day for NO_X and VOC, respectively. EPA has evaluated North Carolina's submittal and has determined that it meets the applicable requirements of the CAA and EPA regulations and is consistent with EPA policy.

V. Statutory and Executive Order Reviews

Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the CAA and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, EPA's role is to approve State choices, provided that they meet the criteria of the CAA. Accordingly, this proposed action merely proposes to approve State law as meeting Federal requirements and does not impose additional requirements beyond those imposed by State law. For that reason, this proposed action:

• Is not a significant regulatory action subject to review by the Office of Management and Budget under Executive Orders 12866 (58 FR 51735, October 4, 1993) and 14094 (88 FR 21879, April 11, 2023);

• 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 subject to Executive Order 13045 (62 FR 19885, April 23, 1997) because it approves a State program;
• Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001); and
• 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.

In addition, the SIP is not approved to apply on any Indian reservation land or in any other area where EPA or an Indian tribe has demonstrated that a tribe has jurisdiction. In those areas of Indian country, the rulemaking does not have Tribal implications and will not impose substantial direct costs on Tribal governments or preempt Tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

Executive Order 12898 (Federal Actions To Address Environmental Justice in Minority Populations and Low-Income Populations, 59 FR 7629, Feb. 16, 1994) directs Federal agencies to identify and address “disproportionately high and adverse human health or environmental effects” of their actions on minority populations and low-income populations to the greatest extent practicable and permitted by law. EPA defines environmental justice (EJ) as “the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income with respect to the development, implementation, and enforcement of environmental laws, regulations, and policies.” EPA further defines the term fair treatment to mean that “no group of people should bear a disproportionate burden of environmental harms and risks, including those resulting from the negative environmental consequences of industrial, governmental, and commercial operations or programs and policies.”

NCDEQ did not evaluate EJ considerations as part of its SIP submittal; the CAA and applicable implementing regulations neither prohibit nor require such an evaluation. EPA did not perform an EJ analysis and did not consider EJ in this proposed action. Due to the nature of the action being proposed here, this proposed action is expected to have a neutral to positive impact on the air quality of the affected area. Consideration of EJ is not required as part of this proposed action, and there is no information in the record inconsistent with the stated goal of E.O. 12898 of achieving EJ for people of color, low-income populations, and Indigenous peoples.

List of Subjects in 40 CFR Part 52

• Environmental protection
• Air pollution control
• Incorporation by reference
• Intergovernmental relations
• Carbon monoxide
• Nitrogen dioxide
• Ozone
• Particulate matter
• Reporting and recordkeeping requirements
• Volatile organic compounds

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

Dated: April 5, 2024.

Jeaneanne Gettle,

Acting Regional Administrator, Region 4.

Footnotes

1.  The North Carolina portion of the Charlotte Maintenance Area for the 2008 8-hour ozone national ambient air quality standards (NAAQS or standards) is comprised of the following counties: Mecklenburg County in its entirety and portions of Cabarrus, Gaston, Iredell, Lincoln, Rowan, and Union Counties. See section II.B. for more detail.

2.  In California, a different on-road emissions model, EMFAC, is used for regulatory purposes instead of MOVES.

3.  The two-year grace period ended on January 9, 2023.

4.  The two-year grace period will end on September 12, 2025.

5.  As discussed above, if EPA approves NCDEQ's December 19, 2022, SIP submittal, emissions inventories for the point and area sources from NCDEQ's September 11, 2019, SIP revision will remain the same.

6.  Information on the changes to the revised nonroad emissions inventory for 2026 can be found on pages 39-40 and in tables 3.9 and 3.10 of the December 19, 2022, submittal. The nonroad mobile sources, referred to as off-road mobile sources, are pieces of equipment that can move but do not use the roadways ( i.e., lawn mowers, construction equipment, railroad locomotives, etc.). The nonroad emissions inventory is separate from the on-road emissions inventory and does not impact the budgets but does impact the amount of the available safety margins. The MOVES3 nonroad modeling data for the nonroad emissions can be found in Appendix B of the submittal.

7.  As with the original SIP revision approved on July 15, 2015, and the last revision approved on August 25, 2021, NCDEQ utilized a five-step approach for determining a factor to use to calculate the amount of safety margin to apply to the budgets for 2026. See Appendix A of the submittal for more detailed information.

8.  These VOC percentages were not clearly delineated in NCDEQ's December 19, 2022, submittal (at table 4.1 in the narrative portion of the submittal and table 4.4-1 in Appendix A). NCDEQ submitted a correction to the December 19, 2022, submittal via a letter dated March 15, 2024, which is in the docket for this proposed rulemaking.