2023-06344. Adequacy Status of Motor Vehicle Emissions Budgets in 2008 8-Hour Ozone Extreme Area and Reasonable Further Progress Plan for Coachella Valley; California

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of adequacy.

SUMMARY:

The Environmental Protection Agency (EPA) is notifying the public that we have found motor vehicle emissions budgets (“budgets”) for the Coachella Valley adequate for transportation conformity purposes. Specifically, our finding relates to budgets in the “Request to Reclassify Coachella Valley for the 2008 8-hour Ozone Standard and the Updated Motor Vehicle Emission Budgets” (“Coachella Valley Extreme RFP Plan”), submitted to the EPA for inclusion in the California state implementation plan (SIP) by the California Air Resources Board (CARB) on December 7, 2022. Upon the effective date of this notice of adequacy, the Southern California Association of Governments (SCAG) and the U.S. Department of Transportation must use these budgets in future transportation conformity analyses.

DATES:

This finding is effective April 12, 2023.

FOR FURTHER INFORMATION CONTACT:

Karina O'Connor, Planning Section (ARD-2-1), Air and Radiation Division, EPA Region IX, 75 Hawthorne Street, San Francisco, CA 94105; [phone] or [e-mail].

SUPPLEMENTARY INFORMATION:

Throughout this document, “we,” “us,” or “our” refer to the EPA.

This notice is simply an announcement of a finding that we have already made. By letter dated March 17, 2023, EPA Region IX notified CARB that the budgets in the Coachella Valley Plan for the reasonable further progress (RFP) years of 2023, 2026, 2029, and 2031 are adequate for transportation conformity purposes.^[1] The finding is available at the EPA's conformity website.^[2]

We announced the availability of the Coachella Valley Extreme RFP Plan and related RFP motor vehicle emissions budgets on the EPA's transportation conformity website on December 21, 2022 and requested comments by January 20, 2023. We received no comments in response to the adequacy review posting. The motor vehicle emissions budgets that we have found adequate are provided in the following table:

Adequate Motor Vehicle Emissions Budgets for the Coachella Valley for the 2008 8-Hour Ozone Standard

[tpd]

Year	Ozone precursor
	VOC	NO X
2023	2.7	6.0
2026	2.5	5.8
2029	2.3	5.8
2031	2.2	5.7

Transportation conformity is required by Clean Air Act section 176(c). The EPA's conformity rule requires that transportation plans, transportation improvement programs, and transportation projects conform to a state's SIP and establishes the criteria and procedures for determining whether or not they conform. Conformity to a SIP means that transportation activities will not produce new air quality violations, worsen existing violations, or delay timely attainment of the national ambient air quality standards.

The criteria we use to determine whether a SIP's motor vehicle emissions budgets are adequate for conformity purposes are outlined in 40 CFR 93.118(e)(4), promulgated on August 15, 1997.^[3] We further described our process for determining the adequacy of submitted SIP budgets in our final rule dated July 1, 2004,^[4] and we used the information in these resources in making our adequacy determination. Please note that an adequacy review is separate from the EPA's completeness review and does not prejudge the EPA's ultimate action on the SIP submittal. Even if we find a budget adequate, the SIP submittal could later be disapproved. Pursuant to 40 CFR 93.104(e), SCAG and the U.S. Department of Transportation will need to demonstrate conformity to the new budgets within two years of the effective date of this notice.^[5] For demonstrating conformity to the new budgets, the on-road motor vehicle emissions from implementation of the transportation plan or program for the area should be projected consistent with the budgets, i.e., by taking the emissions results derived from CARB's EMFAC model (short for EMission FACtor) and then rounding the emissions up to the nearest tenth of a ton per day.

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

Dated: March 22, 2023.

Martha Guzman Aceves,

Regional Administrator, Region IX.

Footnotes

1.  Letter dated March17, 2023, from Elizabeth Adams, Director, Air and Radiation Division, EPA Region IX, to Steven S. Cliff, Executive Officer, CARB.

2.   https://www.epa.gov/​state-and-local-transportation/​conformity-adequacy-review-region-9.

3.  62 FR 43780, 43781-43783.

4.  69 FR 40004, 40038-40047.

5.  See 73 FR 4420 (January 24, 2008).