[Federal Register Volume 86, Number 195 (Wednesday, October 13, 2021)]
[Pages 56930-56932]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-22160]



[EPA-R09-OAR-2021-0648; FRL-9096-03-R9]

Adequacy Status of Post-Attainment Year Motor Vehicle Emissions 
Budgets in 2006 PM2.5 Serious Area Plan for South Coast; California

AGENCY: Environmental Protection Agency (EPA).

[[Page 56931]]

ACTION: Notice of adequacy.


SUMMARY: The Environmental Protection Agency (EPA) is notifying the 
public that the Agency has found that the motor vehicle emissions 
budgets (``budgets'') for the year 2020 in the 2016 Air Quality 
Management Plan (AQMP) for the 2006 fine particulate matter 
(PM2.5) National Ambient Air Quality Standards (NAAQS) in 
the Los Angeles-South Coast Air Basin ``Serious'' nonattainment area 
(``South Coast 2006 PM2.5 Serious Area Plan'') are adequate 
for transportation conformity purposes. The California Air Resources 
Board (CARB) submitted the South Coast 2006 PM2.5 Serious 
Area Plan to the EPA on April 27, 2017, as a revision to the California 
State Implementation Plan (SIP). Upon the effective date of this notice 
of adequacy, the Southern California Association of Governments (SCAG) 
and the U.S. Department of Transportation (DOT) must use the adequate 
budgets in future transportation conformity analyses.

DATES: This finding is effective October 28, 2021.

Division AIR-2, 75 Hawthorne Street, San Francisco, CA 94105-3901; 
(415) 972-3964 or [email protected].

SUPPLEMENTARY INFORMATION: Throughout this document, whenever ``we,'' 
``us,'' or ``our'' is used, we mean the EPA.
    Today's notice is simply an announcement of a finding that we have 
already made. By letter dated September 28, 2021, EPA Region IX 
notified CARB that the budgets in the South Coast 2006 PM2.5 
Serious Area Plan for the reasonable further progress (RFP) post-
attainment milestone year of 2020 are adequate.\1\ The finding is 
available at EPA's conformity website: https://www.epa.gov/state-and-local-transportation/conformity-adequacy-review-region-9. We announced 
the availability of the South Coast 2006 PM2.5 Serious Area 
Plan and related 2020 budgets on the EPA's transportation conformity 
website on April 16, 2021. We received no comments in response to the 
adequacy review posting. The adequate motor vehicle emissions budgets 
are provided in the following table:

    \1\ Letter from Elizabeth Adams, Director, Air and Radiation 
Division, EPA Region IX, to Richard Corey, Executive Officer, CARB.

              Adequate Motor Vehicle Emissions Budgets in South Coast 2006 PM2.5 Serious Area Plan
                                         [Annual average, tons per day]
                                                                 emitted fine       Nitrogen         Volatile
                         Budget year                             particulate      oxides (NOX)       organic
                                                                matter (PM2.5)                   compounds (VOC)
2020.........................................................              20              152               77

    Transportation conformity is required by Clean Air Act section 
176(c). The EPA's conformity rule requires that transportation plans, 
transportation improvement programs, and projects conform to SIPs and 
establishes the criteria and procedures for determining whether or not 
they do conform.\2\ Conformity to a SIP means that transportation 
activities will not produce new air quality violations, worsen existing 
violations, or delay timely attainment of the NAAQS.

    \2\ 40 CFR part 93, subpart A.

    The criteria by which we determine whether a SIP's budgets are 
adequate for conformity purposes are outlined in 40 CFR 93.118(e)(4), 
which was promulgated in our August 15, 1997 final rule.\3\ We further 
described our process for determining the adequacy of submitted SIP 
budgets in our July 1, 2004 final rule \4\ and we used the information 
in these resources in making the adequacy determination announced in 
this notice.

    \3\ 62 FR 43780, 43781-43783.
    \4\ 69 FR 40004, 40038.

    The EPA approved the South Coast 2006 PM2.5 Serious Area 
Plan on February 12, 2019.\5\ In that action, we approved the budgets 
for the 2017 RFP year and the 2019 attainment year. We also approved a 
trading mechanism for transportation conformity analyses that allows 
future decreases in NOX from on-road mobile sources to 
offset any on-road increases in PM2.5, based on specified 
trading ratios.\6\ The South Coast Air Quality Management District 
(SCAQMD) indicated that the trading mechanism was included in the 2016 
AQMP for approval by the EPA for use by SCAG in conformity 
determinations for the 2006 PM2.5 NAAQS for analysis years 
after the attainment year of 2019.\7\

    \5\ 84 FR 3305.
    \6\ 83 FR 49872, 49891-49894 (October 3, 2018).
    \7\ Letter dated March 14, 2018, from Philip Fine, Deputy 
Executive Officer, Planning, Rule Development, and Area Sources, 
SCAQMD, to Amy Zimpfer, Associate Director, Air Division, EPA Region 
IX, regarding trading ratios among PM2.5 precursors.

    Consistent with the requirements set out in our implementation rule 
for the PM2.5 NAAQS,\8\ we did not act on the RFP budget for 
the post-attainment year of 2020 when we approved the South Coast 2006 
PM2.5 Serious Area Plan. As we noted in our proposed 
approval of the South Coast 2006 PM2.5 Serious Area Plan, it 
is not necessary to demonstrate conformity for 2020 or to use the 2020 
budgets until such time as the area fails to attain the 2006 24-hour 

    \8\ ``Fine Particulate Matter National Ambient Air Quality 
Standards: State Implementation Plan Requirements Rule,'' 81 FR 
58010 (August 24, 2016).

    On September 16, 2020, the EPA determined that the Los Angeles-
South Coast Air Basin had failed to attain the 2006 24-hour 
PM2.5 NAAQS by its December 31, 2019 attainment date.\9\ 
Because of that failure to attain, we evaluated the submitted budgets 
for 2020 in the South Coast 2006 PM2.5 Serious Area Plan to 
determine whether they are adequate for conformity purposes.

    \9\ 85 FR 57733.

    Pursuant to 40 CFR 93.104(e), within two years of the effective 
date of this notice, SCAG and the DOT will need to demonstrate 
conformity. For demonstrating conformity to the budgets in this plan, 
the on-road motor vehicle emissions from implementation of the 
transportation plan or program should be projected consistently with 
the budgets in this plan, 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 ton. The previously approved trading 
mechanism may be used in connection with the new budgets.
    Authority: 42 U.S.C. 7401 et seq.

[[Page 56932]]

    Dated: October 5, 2021.
Deborah Jordan,
Acting Regional Administrator, Region IX.
[FR Doc. 2021-22160 Filed 10-12-21; 8:45 am]