District and keep weekly records relating to the quantities of meat
cooked.\309\ CARB submitted the amended rule to the EPA on November 21,
2018, and the EPA has not yet proposed any action on this submission.
The EPA approved a prior version of this rule into the SIP on November
3, 2011.\310\ The District states that the 2018 amendment was an
important first step in its ongoing process to develop a new control
measure that will include financial incentives to help fund accelerated
deployment of under-fired charbroiler emission control
technologies.\311\ The 2018 amendments do not, however, establish any
new control requirements and therefore do not achieve additional
emission reductions beyond those that continue to be achieved by the
SIP-approved version of Rule 4692.
---------------------------------------------------------------------------

    \309\ SJVUAPCD Rule 4692, as amended June 21, 2018, and
SJVUAPCD, Final Draft Staff Report, ``Amendments to Rule 4692
(Commercial Charbroiling),'' June 21, 2018, 1 and 5-6.
    \310\ 76 FR 68103 (November 3, 2011) (approving Rule 4692 as
amended September 17, 2009).
    \311\ SJVUAPCD, Final Draft Staff Report, ``Amendments to Rule
4692 (Commercial Charbroiling),'' June 21, 2018, 1.
---------------------------------------------------------------------------

    Second, the District amended Rule 4905 (``Natural Gas-fired, Fan-
type, Residential Central Furnaces'') on June 21, 2018, to extend the
period during which manufacturers may pay emission fees in lieu of
meeting the rule's NOX

emission limits.\312\ CARB submitted the amended rule to the EPA on
November 21, 2018, and the EPA has not yet proposed any action on this
submission. The EPA approved a prior version of Rule 4905 into the
California SIP on March 29, 2016.\313\ As part of that rulemaking, the
EPA noted that because of the option in Rule 4905 to pay mitigation
fees in lieu of compliance with emission limits, emission reductions
associated with the rule's emission limits would not be creditable in
any attainment plan without additional documentation.\314\ Until the
District submits the necessary documentation to credit emission
reductions achieved by Rule 4905 toward an attainment control strategy,
this rule is not creditable for SIP purposes. The 2018 PM2.5
Plan indicates that the District attributed 0.26 tpd of NOX
reductions between 2013 and 2024 to Rule 4905.\315\ These emission
reductions have de minimis impacts on the attainment demonstration in
the SJV PM2.5 Plan.
---------------------------------------------------------------------------

    \312\ SJVUAPCD, Final Draft Staff Report, ``Proposed Amendments
to Rule 4905 (Natural Gas-fired, Fan-type Central Furnaces),'' 2.
    \313\ 81 FR 17390 (March 29, 2016) (approving Rule 4905 as
amended January 22, 2015).
    \314\ EPA, Region IX Air Division, ``Technical Support Document
for EPA's Proposed Rulemaking for the California State
Implementation Plan (SIP), San Joaquin Valley Unified Air Pollution
Control District's Rule 4905, Natural Gas-Fired, Fan-Type Central
Furnaces,'' October 5, 2015, n. 8.
    \315\ 2018 PM2.5 Plan, App. C, C-290.
---------------------------------------------------------------------------

    Third, the District amended Rule 9510 (``Indirect Source Review'')
on December 21, 2017, to eliminate inconsistencies in its applicability
provisions and to ensure that all large development projects are
subject to the rule.\316\ CARB submitted this rule to the EPA on May
23, 2018, and the EPA has not yet proposed any action on the
submission. The EPA approved a prior version of this rule into the
California SIP on May 9, 2011.\317\ As part of that rulemaking, the EPA
noted that emission reductions associated with this rule would not be
creditable in any attainment or RFP demonstration unless the District
revises the rule to address the EPA's enforceability concerns.\318\
Until the District adopts such revisions to the rule, Rule 9510 is not
creditable for SIP purposes. The 2018 PM2.5 Plan does not,
however, appear to rely on this rule to any measurable extent in the
projected attainment inventory.\319\ Therefore, the District's
inclusion of this rule in Table 4-1 of the 2018 PM2.5 Plan
has no impact on our evaluation of the attainment demonstration.
---------------------------------------------------------------------------

    \316\ SJVUAPCD, Final Draft Staff Report, ``Rule 9510 Indirect
Source Review.'' December 21, 2017, 1.
    \317\ 76 FR 26609 (May 9, 2011) (approving Rule 9510 as amended
December 15, 2005).
    \318\ 76 FR 26609, 26612-26614.
    \319\ The District's control analysis states that there is no
emissions inventory specific to Rule 9510. 2018 PM2.5
Plan, App. C, C-302.
---------------------------------------------------------------------------

    Finally, the 2018 PM2.5 Plan lists Rule 4203
(``Particulate Matter Emissions from Incineration of Combustible
Refuse'') as a baseline measure. This rule has not been approved into
the California SIP.\320\ Appendix C of the 2018 PM2.5 Plan
states, however, that the emissions inventory for incineration of
combustible refuse is 0.00 tpd of NOX and 0.00 direct
PM2.5 from 2013 through 2024.\321\ Thus, to the extent the
District relied upon emission reductions achieved by this rule in its
future baseline emissions estimates, those emission reductions have de
minimis impacts on the attainment demonstration in the SJV
PM2.5 Plan.
---------------------------------------------------------------------------

    \320\ The EPA does not have any pending SIP submission for Rule
4203.
    \321\ 2018 PM2.5 Plan, App. C, C-46.
---------------------------------------------------------------------------

    In sum, although Table 4-1 of the 2018 PM2.5 Plan
identifies four baseline measures that are not creditable for SIP
purposes at this time, we find that the total emission reductions
attributed to these four measures in the future baseline inventories
have de minimis impacts on the attainment demonstration in the Plan.
ii. Additional Measures and Aggregate Commitments
    The SJV PM2.5 Plan relies on an incentive-based measure
recently adopted by CARB to achieve 5.9 tpd of NOX
reductions and 0.3 tpd of direct PM2.5 reductions--2.9% and
4.7%, respectively, of the total NOX and direct
PM2.5 emission reductions necessary for the San Joaquin
Valley to attain the 2006 PM2.5 NAAQS by December 31,
2024.\322\ Under longstanding guidance, the EPA has recommended
presumptive limits on the amounts of emission reductions from certain
voluntary and other nontraditional measures that may be credited in a
SIP. Specifically, for voluntary mobile source emission reduction
programs, the EPA has identified a presumptive limit of three percent
(3%) of the total projected future year emission reductions required to
attain the appropriate NAAQS, and for any particular SIP submittal to
demonstrate attainment or maintenance of the NAAQS or progress toward
attainment (RFP), 3% of the specific statutory requirement.\323\ The
EPA may, however, approve measures for SIP credit in amounts exceeding
the presumptive limits where a clear and convincing justification is
made by the State as to why a higher limit should apply in its
case.\324\
---------------------------------------------------------------------------

    \322\ The 2018 PM2.5 Plan shows that 202.2 tpd of
NOX and 6.4 tpd of PM2.5 emission reductions
are necessary for San Joaquin Valley to attain the 2006
PM2.5 NAAQS by December 31, 2024. 2018 PM2.5
Plan, revised App. H, Table H-6. For further discussion of Appendix
H, see section IV.E of this preamble.
    \323\ EPA, ``Guidance on Incorporating Voluntary Mobile Source
Emission Reduction Programs in State Implementation Plans (SIPs),''
October 24, 1997, 5.
    \324\ EPA, ``Incorporating Emerging and Voluntary Measure in a
State Implementation Plan (SIP),'' October 4, 2004, 9; see also EPA,
``Guidance on Incorporating Bundled Measures in a State
Implementation Plan,'' August 16, 2005, 8, n. 6, and EPA, ``Diesel
Retrofits: Quantifying and Using Their Emission Benefits in SIPs and
Conformity: Guidance for State and Local Air and Transportation
Agencies,'' March 2018, 12.
---------------------------------------------------------------------------

    The San Joaquin Valley's topography and meteorology present
significant challenges for air quality. As stated in the 2018
PM2.5 Plan, ``the surrounding mountains trap pollution and
block airflow'' and ``[t]emperature inversions, while present to some
degree throughout the year, can last for days during the winter,
holding in nighttime accumulations of pollutants.'' \325\ In addition,
the population of the area continues to grow at a rate higher than the
statewide growth rate, leading to increased vehicular traffic along
major highways that run through the San Joaquin Valley.\326\ Given
these unique challenges, both the State and District continue to
implement both traditional and non-traditional emission reduction
strategies to attain the PM2.5 standards in the San Joaquin
Valley, including regulatory programs, incentive programs, and rigorous
outreach and education efforts.\327\ Over the past several decades, the
State and District have developed and implemented several comprehensive
plans to address attainment of the NAAQS for ozone and particulate
matter.\328\ These attainment plans have resulted in the State's and
District's adoption of numerous regulations for stationary, area, and
mobile sources, many of which are among the most stringent control
measures in the nation. Given the air quality needs of the area and the
numerous control measures that both the State and District have adopted
and

implemented in the San Joaquin Valley to date, we believe it is
appropriate to allow the State to rely on the Valley Incentive Measure
to achieve 2.9% (5.9 tpd) of the NOX reductions and 4.7%
(0.3 tpd) of the direct PM2.5 reductions necessary for the
area to attain the 2006 PM2.5 NAAQS by the end of 2024.
---------------------------------------------------------------------------

    \325\ 2018 PM2.5 Plan, Ch. 2, 2-1.
    \326\ Id. at 2-4.
    \327\ Id. at 2-2.
    \328\ See, e.g., 69 FR 30005 (May 26, 2004) (approving plan to
attain the 1987 PM10 NAAQS), 76 FR 69896 (November 9,
2011) (partially approving and partially disapproving plan to attain
the 1997 PM2.5 NAAQS), 77 FR 12652 (March 1, 2012)
(approving plan to attain the 1997 8-hour ozone NAAQS), and 81 FR
19492 (April 5, 2016) (approving plan to attain the 1979 1-hour
ozone NAAQS).
---------------------------------------------------------------------------

    For the remainder of the emission reductions necessary for
attainment, the SJV PM2.5 Plan identifies a series of
additional State and District commitments to achieve emission
reductions through additional control measures beyond baseline measures
that will contribute to expeditious attainment of the 2006
PM2.5 NAAQS. For mobile sources, CARB's commitment
identifies a list of 12 State regulatory measures and three incentive-
based measures that CARB has committed to propose to its Board for
consideration by specific dates.\329\ For stationary sources, the
District's commitment identifies a list of nine regulatory measures and
three incentive-based measures that the District has committed to
propose to its Board for consideration by specific dates.\330\ The Plan
contains CARB's and the District's estimates of the emission reductions
that would be achieved by each of these additional measures, if
adopted.\331\
---------------------------------------------------------------------------

    \329\ CARB Resolution 18-49 (October 25, 2018), Attachment A and
Valley State SIP Strategy, Table 7 (``State Measures and Schedule
for the San Joaquin Valley''). The EPA is excluding two State
measures listed in Table 7 of the Valley State SIP Strategy--the
``Advanced Clean Cars 2'' measure and the ``Cleaner In-Use
Agricultural Equipment'' measure--because these measures are
scheduled for implementation in 2026 and 2030, respectively, well
after the January 1, 2024 implementation deadline for control
measures necessary for attainment by December 31, 2024. 40 CFR
51.1011(b)(5).
    \330\ SJVUAPCD Governing Board Resolution 18-11-16 (November 15,
2018) and 2018 PM2.5 Plan, Table 4-4 (``Proposed
Regulatory Measures'') and Table 4-5 (``Proposed Incentive-Based
Measures'').
    \331\ 2018 PM2.5 Plan, Ch. 4, Table 4-3 (''Emission
Reductions from District Measures'') and Table 4-9 (''San Joaquin
Valley Expected Emission Reductions from State Measures'') and
Valley State SIP Strategy, Table 8 (``San Joaquin Valley Expected
Emission Reductions from State Measures'').
---------------------------------------------------------------------------

    CARB's commitments are contained in CARB Resolution 18-49 (October
25, 2018) and the Valley State SIP Strategy and consist of two parts: A
control measure commitment and a tonnage commitment. First, CARB has
committed to ``begin the measure's public process and bring to the
Board for consideration the list of proposed SIP measures outlined in
the Valley State SIP Strategy and included in Attachment A, according
to the schedule set forth.'' \332\ By email dated November 12, 2019,
CARB confirmed that it intended to begin the public process on each
measure by discussing the proposed regulation or program at a public
meeting (workshop, working group, or Board hearing) or in a publicly-
released document and to then propose the regulation or program to its
Board.\333\ Second, CARB has committed ``to achieve the aggregate
emissions reductions outlined in the Valley State SIP Strategy of 32
tpd of NOX and 0.9 tpd of PM2.5 emissions
reductions in the San Joaquin Valley by 2024.'' \334\ The Valley State
SIP Strategy explains that CARB's overall commitment is to ``achieve
the total emission reductions necessary to attain the federal air
quality standards, reflecting the combined reductions from the existing
control strategy and new measures'' and that ``if a particular measure
does not get its expected emissions reductions, the State is still
committed to achieving the total aggregate emission reductions.'' \335\
---------------------------------------------------------------------------

    \332\ CARB Resolution 18-49 (October 25, 2018), 5.
    \333\ Email dated November 12, 2019, from Sylvia Vanderspek,
CARB to Anita Lee, EPA Region IX, ``RE: SJV PM2.5
information'' (attaching ``Valley State SIP Strategy Progress'') and
CARB Staff Report, 14.
    \334\ CARB Resolution 18-49 (October 25, 2018), 5.
    \335\ Valley State SIP Strategy, 7.
---------------------------------------------------------------------------

    The District's commitments are contained in SJVUAPCD Governing
Board Resolution 18-11-16 (November 15, 2018) and Chapter 4 of the 2018
PM2.5 Plan and similarly consist of two parts: A control
measure commitment and a tonnage commitment. First, the District has
committed to ``take action on the rules and measures committed to in
Chapter 4 of the Plan by the dates specified therein, and to submit
these rules and measures, as appropriate, to CARB within 30 days of
adoption for transmittal to EPA as a revision to the [SIP].'' \336\ By
email dated November 12, 2019, the District confirmed that it intended
to take action on the listed rules and measures by beginning the public
process on each measure, i.e., discussing the proposed regulation or
program at a public meeting, including a workshop, working group, or
Board hearing, or in a publicly-released document, and then proposing
the rule or measure to the SJVUAPCD Governing Board.\337\ Second, the
District has committed to ``achieve the aggregate emissions reductions
of 1.88 tpd of NOX and 1.3 tpd of PM2.5 by 2024/
2025'' through adoption and implementation of these measures or, if the
total emission reductions from these rules or measures are less than
these amounts, ``to adopt, submit, and implement substitute rules and
measures that achieve equivalent reductions in emissions of direct
PM2.5 or PM2.5 precursors'' in the same
implementation timeframes.\338\
---------------------------------------------------------------------------

    \336\ SJVUAPCD Governing Board Resolution 18-11-16 (November 15,
2018), 10-11.
    \337\ Email dated November 12, 2019, from Jon Klassen, SJVUAPCD
to Wienke Tax, EPA Region IX, ``RE: follow up on aggregate
commitments in SJV PM2.5 plan'' (attaching ``District
Progress In Implementing Commitments with 2018 PM2.5
Plan'').
    \338\ SJVUAPCD Governing Board Resolution 18-11-16 (November 15,
2018), 10-11.
---------------------------------------------------------------------------

    In November 2019, CARB provided status updates on its progress to
date on developing and adopting the additional mobile source measures
identified in its control measure commitment.\339\ Table 7 lists each
measure and provides a summary of the anticipated emission reductions
and the current status for each measure. As shown in the ``Current
Status'' column, CARB has adopted five measures and begun the public
process on seven of the remaining 10 measures listed in its control
measure commitment.
---------------------------------------------------------------------------

    \339\ Email dated November 12, 2019, from Sylvia Vanderspek,
CARB to Anita Lee, EPA Region IX, ``RE: SJV PM2.5
information'' (attaching ``Valley State SIP Strategy Progress'').

                             Table 7--Status of CARB Compliance With Control Measure Commitments for the San Joaquin Valley
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Direct PM2.5
                                                                                NOX emission       emission
            Count                     Measure         Public process      Action       Implementation     reductions       reductions     Current status
                                                          begins                           begins           (tpd)            (tpd)             \a\

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            2016 State SIP Strategy Measures
--------------------------------------------------------------------------------------------------------------------------------------------------------
1............................  Lower Opacity Limits             2016            2018  2018-2024......  6.8............  <0.1...........  Adopted July
                                for Heavy-Duty                                                                                25, 2018.
                                Vehicles.
2............................  Amended Warranty                 2016            2018  2022...........  ...............  ...............  Adopted June
                                Requirements for                                                                                28, 2018.
                                Heavy-Duty Vehicles.
3............................  Heavy-Duty Vehicle               2019            2020  2022 +.........  ...............  ...............  Public process
                                Inspection and                                                                                began February
                                Maintenance (I/M)                                                                                11, 2019.
                                Program.
4............................  Heavy-Duty Low-NOX               2016            2019  2023...........  0.7............  ...............  Public process
                                Engine Standard--                                                                                began November
                                California Action.                                                                                3, 2016.

5............................  Innovative Clean                 2015       2018-2019  2020...........  <0.1...........  <0.1...........  Adopted
                                Transit.                                                                                December 14,
                                                                                2018.
6............................  Advanced Clean Local             2016            2019  2020...........  <0.1...........  <0.1...........  Public process
                                Trucks (Last Mile                                                                                began November
                                Delivery).                                                                                1, 2016.
7............................  Zero-Emission Airport            2017            2018  2023...........  NYQ............  NYQ............  Adopted June
                                Shuttle Buses.                                                                                27, 2019.
8............................  Zero-Emission Off-               2020            2020  2023...........  ...............  ...............  Public process
                                Road Forklift                                                                                to begin 2020.
                                Regulation Phase 1.
9............................  Zero-Emission Airport            2018            2019  2023...........  <0.1...........  <0.1...........  Public process
                                Ground Support                                                                                began June 6,
                                Equipment.                                                                                2018.
10...........................  Small Off-Road                   2016       2018-2020  2022...........  0.1............  <0.1...........  Public process
                                Engines.                                                                                began May 23,
                                                                                2016.
11...........................  Transport                        2016       2018-2019  2020 +.........  NYQ............  NYQ............  Public process
                                Refrigeration Units                                                                                began April
                                Used for Cold                                                                                13, 2016.
                                Storage.
12...........................  Low-Emission Diesel              2019            2021  2023...........  0.8............  0.1............  Public process
                                Fuel Requirement.                                                                                began October
                                                                                18, 2019.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                           Proposed State Measures for the Valley (Valley State SIP Strategy)
--------------------------------------------------------------------------------------------------------------------------------------------------------
13...........................  Accelerated Turnover             2018         by 2021  Ongoing........  10.............  NYQ............  Public process
                                of Trucks and Buses                                                                                to begin by
                                Incentive Projects                                                                                2021.
                                \b\.
14...........................  Accelerated Turnover             2018         by 2020  Ongoing........  Existing 3; New  Existing 0.2;    CARB adopted
                                of Agricultural                                                         8.               New 0.6.         December 12,
                                Equipment Incentive                                                                                2019.
                                Projects \b\.
15...........................  Accelerated Turnover             2020         by 2021  Ongoing........  2..............  NYQ............  Public process
                                of Off-Road                                                                                to begin by
                                Equipment Incentive                                                                                2021.
                                Projects \b\.
                                                                                --------------------------------------------------
                              Total Estimated Emission Reductions (tpd)                                32.............  1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sources: 2018 PM2.5 Plan, Tables 4-8 and 4-9 and email dated November 12, 2019, from Sylvia Vanderspek, CARB to Anita Lee, EPA Region IX, ``RE: SJV
  PM2.5 information'' (attaching ``Valley State SIP Strategy Progress'').
NYQ means ``not yet quantified.''
\a\ For references on the current status of these measures, see section VIII of the EPA's General Evaluation TSD.
\b\ Indicates that CARB intends to develop a SIP-creditable measure to demonstrate that the emission reductions from incentive projects can be credited
  towards the aggregate commitment.

    In November 2019, the District also provided status updates on its
progress to date on developing and adopting the additional stationary
source measures identified in its control measure commitment.\340\
Table 8 lists each measure and provides a summary of the anticipated
emission reductions and the current status for each measure. As shown
in the ``Current Status'' column, the District has adopted and
submitted one of these measures (the 2019 amendment to Rule 4901) to
the EPA for approval into the SIP and has begun the public process on
five of the remaining 11 measures listed in its control measure
commitment.\341\
---------------------------------------------------------------------------

    \340\ Email dated November 12, 2019, from Jon Klassen, SJVUAPCD
to Wienke Tax, EPA Region IX, ``RE: follow up on aggregate
commitments in SJV PM2.5 plan'' (attaching ``District
Progress In Implementing Commitments with 2018 PM2.5
Plan'').
    \341\ The EPA has recently proposed to approve amended Rule 4901
into the California SIP. 85 FR 1131.

                           Table 8--Status of SJVUAPCD Compliance with Control Measure Commitments for the San Joaquin Valley
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Direct PM2.5
                                                                                NOX emission       emission
            Count                     Measure         Public process    Action date    Implementation     reductions       reductions     Current status
                                                          begins                           begins           (tpd)            (tpd)             \a\

--------------------------------------------------------------------------------------------------------------------------------------------------------
1............................  Rule 4311                        2018            2020  2023...........  0.05...........  ...............  Public workshop
                                (``Flares'').                                                                                held November
                                                                                13, 2019.
2............................  Rule 4306 (``Boilers,            2019            2020  2023...........  0.76...........  0.03...........  Public scoping
                                Steam Generators,                                                                                meeting held
                                and Process Heaters--                                                                                December 5,
                                Phase 3'').                                                                                2019.
3............................  Rule 4320 (``Advanced  ..............  ..............  ...............  ...............  ...............  Public scoping
                                Emission Reduction                                                                                meeting held
                                Options for Boilers,                                                                                December 5,
                                Steam Generators,                                                                                2019.
                                and Process Heaters
                                Greater than 5.0
                                MMBtu/hr'').
4............................  Rule 4354 (``Glass               2020            2021  2023...........  ...............  ...............  Public process
                                Melting Furnaces'').                                                                                to begin in
                                                                                2020.
5............................  Rule 4352 (``Solid               2020            2021  2023...........  ...............  ...............  Public process
                                Fuel-Fired Boilers,                                                                                to begin in
                                Steam Generators and                                                                                2020.
                                Process Heaters'').
6............................  Rule 4702 (``Internal            2019            2020  2024...........  ...............  ...............  Public scoping
                                Combustion                                                                                meeting held
                                Engines'').                                                                                December 5,
                                                                                2019.
7............................  Rule 4550                        2021            2022  2024...........  ...............  0.32...........  Public process
                                (``Conservation                                                                                to begin in
                                Management                                                                                2021.
                                Practices'').
8............................  Rule 4692                        2019            2020  2024...........  ...............  ...............  Public scoping
                                (``Commercial Under-                                                                                meeting held
                                fired                                                                                December 12,
                                Charbroilers'').                                                                                2019.

9............................  Rule 4901                        2019            2019  2019...........  ...............  0.26...........  Rule adopted
                                (``Woodburning                                                                                June 20, 2019
                                Fireplaces and Wood                                                                                and submitted
                                Burning Heaters'')                                                                                to EPA July
                                (Hot-spot strategy).                                                                                22, 2019.
10...........................  Agricultural                     2019            2020  Ongoing........  1.07...........  ...............  Public process
                                Operation Internal                                                                                pending.
                                Combustion Engines
                                Incentive Projects.
11...........................  Commercial Under-                2019            2020  Ongoing........  ...............  0.53...........  Public process
                                fired.                                                                                pending.
                               Charbroiling
                                Incentive Projects.
12...........................  Residential Wood                 2019            2020  Ongoing........  ...............  0.16...........  Public process
                                Burning Devices                                                                                pending.
                                Incentive Projects.
                                                                                --------------------------------------------------
                              Total Estimated Emission Reductions (tpd)                                1.88...........  1.3
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sources: 2018 PM2.5 Plan, Chapter 4, Tables 4-3, 4-4, and 4-5 and Appendix E, Table E-3; SJVUAPCD, Final Draft Staff Report, ``Amendments to District's
  Residential Wood Burning Emission Reduction Strategy,'' June 20, 2019 (``2019 Rule 4901 Staff Report''); and email dated November 12, 2019, from Jon
  Klassen, SJVUAPCD to Wienke Tax, EPA Region IX, ``RE: follow up on aggregate commitments in SJV PM2.5 plan'' (attaching ``District Progress In
  Implementing Commitments with 2018 PM2.5 Plan'').
\a\ For references on the current status of these measures, see section VIII of the EPA's General Evaluation TSD.

    With respect to Rule 4901 (``Wood Burning Fireplaces and Wood
Burning Heaters''), the District amended this rule on June 20, 2019, to
establish more stringent limitations on the use of residential wood
burning devices. Specifically, the June 20, 2019 amendment to Rule 4901
lowered the thresholds at which ``No Burn'' days will be imposed to
limit direct PM2.5 emissions from residential wood burning
during the November through February timeframe in three ``hot spot''
counties (Fresno, Kern, and Madera).\342\ CARB submitted this amended
rule to the EPA on July 22, 2019, and the EPA has proposed to approve
the amended rule into the California SIP.\343\ The EPA approved a prior
version of this rule into the SIP on October 6, 2016.\344\ The
District's control measure commitment for 2024 and 2025 in Chapter 4 of
the 2018 PM2.5 Plan indicates that the District expects to
achieve 0.42 tpd of direct PM2.5 emission reductions through
implementation of its residential wood burning strategy, including
implementation of the ``No Burn'' provisions in amended Rule 4901.\345\
Upon the EPA's final action to approve amended Rule 4901 into the SIP,
the additional emission reductions resulting from the ``No Burn''
provisions of the amended rule may be credited toward the attainment
demonstration in the Plan.
---------------------------------------------------------------------------

    \342\ The revised rule adds additional restrictions on the
installation of wood burning devices, new requirements for fireplace
and chimney remodel projects, additional requirements for
residential real estate sales, non-seasoned wood to the list of
prohibited fuel types, a new visible emissions limit for fireplaces
and non-registered devices, and other editorial revisions to improve
rule clarity. The emission reductions from these additional
revisions were not quantified.
    \343\ 85 FR 1131.
    \344\ 81 FR 69393 (October 6, 2016) (approving Rule 4901 as
amended September 18, 2014).
    \345\ 2018 PM2.5 Plan, Ch. 4, Table 4-3.
---------------------------------------------------------------------------

    We note that the District's current estimate of direct
PM2.5 emission reductions to be achieved through the ``No
Burn'' provisions of amended Rule 4901 (0.26 tpd) is based on a
compliance rate (referred to as a ``control efficiency'') of 100%. The
District estimates an actual control efficiency of 97% to 99%, based on
the District's surveillance of neighborhoods in the San Joaquin
Valley.\346\ This control efficiency is significantly higher than the
75% control efficiency that EPA guidance attributes to wood burning
curtailment programs.\347\ Because the District has not provided
adequate support for a 97-100% rule effectiveness rate, we are
crediting the amended rule at this time with 0.20 tpd of direct
PM2.5 emission reductions toward the attainment control
strategy, based on a 75% control efficiency. We have factored this
amount into the direct PM2.5 emission reductions from
approved measures, shown in Row C of Table 9.
---------------------------------------------------------------------------

    \346\ Email dated October 9, 2019 from Jon Klassen, SJVUAPCD to
Meredith Kurpius, EPA Region IX, Subject: ``RE: Info to support Rule
4901.''
    \347\ Strategies for Reducing Wood Smoke, EPA-456/B-13-01, March
2013, 42.
---------------------------------------------------------------------------

    Table 9 provides a summary of the total NOX and direct
PM2.5 emission reductions necessary for attainment in the
San Joaquin Valley by December 31, 2024, the emission reductions
attributed to baseline measures and new control strategy measures, and
the emission reductions remaining as aggregate tonnage commitments.
Approximately 13.8% of the NOX reductions necessary for
attainment and 26.6% of the direct PM2.5 reductions
necessary for attainment remain as aggregate tonnage commitments.

                   Table 9--Reductions Needed for Attainment and Aggregate Tonnage Commitments
                                                   [tpd, 2024]
----------------------------------------------------------------------------------------------------------------
                                                                                Direct PM2.5
                                                                                NOX
----------------------------------------------------------------------------------------------------------------
A.....................................  Total reductions needed from baseline              202.2             6.4
                                         and control strategy measures.
B.....................................  Reductions from baseline measures.......           168.3             4.2
C.....................................  Total reductions from approved measures.             5.9             0.5
D.....................................  Total reductions remaining as                       28.0             1.7
                                         commitments (A-B-C).
E.....................................  Percent of total reductions needed                 13.8%           26.6%
                                         remaining as commitments (D/A).
----------------------------------------------------------------------------------------------------------------
Sources: 2018 PM2.5 Plan, Ch. 4, Tables 4-3 and 4-7, and Appendix B, Tables B-1 and B-2; 2019 Rule 4901 Staff
  Report, 34; and ``Air Plan Approval; California; San Joaquin Valley Unified Air Pollution Control District''
  (proposed rule to approve ``San Joaquin Valley Agricultural Equipment Incentive Measure''), pre-publication
  notice signed February 13, 2020.

    The CAA allows for approval of enforceable commitments that are
limited in scope where circumstances exist that warrant the use of such
commitments in place of adopted measures.\348\ Specifically, CAA
section 110(a)(2)(A) provides that each SIP ``shall include enforceable
emission limitations and other control measures, means or techniques .
. . as well as schedules and timetables for compliance, as may be
necessary or appropriate to meet the applicable requirement of the
Act.'' Section 172(c)(6) of the Act, which applies to nonattainment
SIPs, is virtually identical to section 110(a)(2)(A). The language in
these sections of the CAA is quite broad, allowing a SIP to contain any
``means or techniques'' that the EPA determines are ``necessary or
appropriate'' to meet CAA requirements, such that the area will attain
as expeditiously as practicable, but no later than the designated date.
Furthermore, the express allowance for ``schedules and timetables''
demonstrates that Congress understood that all required controls might
not have to be in place before a SIP could be fully approved.
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    \348\ Commitments approved by the EPA under CAA section
110(k)(3) are enforceable by the EPA and citizens under CAA sections
113 and 304, respectively. In the past, the EPA has approved
enforceable commitments and courts have enforced these actions
against states that failed to comply with those commitments. See,
e.g., American Lung Ass'n of N.J. v. Kean, 670 F. Supp. 1285 (D.N.J.
1987), aff'd, 871 F.2d 319 (3rd Cir. 1989); NRDC, Inc. v. N.Y. State
Dept. of Env. Cons., 668 F. Supp. 848 (S.D.N.Y. 1987); Citizens for
a Better Env't v. Deukmejian, 731 F. Supp. 1448, recon. granted in
par, 746 F. Supp. 976 (N.D. Cal. 1990); Coalition for Clean Air v.
South Coast Air Quality Mgt. Dist., No. CV 97-6916-HLH, (C.D. Cal.
Aug. 27, 1999). Further, if a state fails to meet its commitments,
the EPA could make a finding of failure to implement the SIP under
CAA section 179(a), which starts an 18-month period for the State to
correct the non-implementation before mandatory sanctions are
imposed.
---------------------------------------------------------------------------

    Once the EPA determines that circumstances warrant consideration of
an enforceable commitment to satisfy a CAA requirement, it considers
three factors in determining whether to approve the enforceable
commitment: (a) Does the commitment address a limited portion of the
CAA requirement; (b) is the state capable of fulfilling its commitment;
and (c) is the commitment for a reasonable and appropriate period of
time.\349\
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    \349\ The Fifth Circuit Court of Appeals upheld the EPA's
interpretation of CAA sections 110(a)(2)(A) and 172(c)(6) and the
Agency's use and application of the three factor test in approving
enforceable commitments in the 1-hour ozone SIP for Houston-
Galveston. BCCA Appeal Group et al. v. EPA et al., 355 F.3d 817 (5th
Cir. 2003). More recently, the Ninth Circuit Court of Appeals upheld
the EPA's approval of enforceable commitments in ozone and
PM2.5 SIPs for the San Joaquin Valley, based on the same
three factor test. Committee for a Better Arvin, et al. v. EPA, 786
F.3d 1169 (9th Cir. 2015).
---------------------------------------------------------------------------

    With respect to the SJV PM2.5 Plan, circumstances
warrant the consideration of enforceable commitments as part of the
attainment demonstration for this area. As shown in Table 9 of this
preamble, the majority of the emissions reductions needed to
demonstrate attainment and RFP in the San Joaquin Valley are achieved
by rules and regulations adopted prior to the State's development of
the SJV PM2.5 Plan, i.e., baseline measures. As a result of
these already-adopted State and District measures, most air pollution
sources in the San Joaquin Valley were already subject to stringent
rules prior to the development of the SJV PM2.5 Plan,
leaving fewer and more technologically-challenging opportunities to
reduce emissions. Despite these significant emission reductions, as
shown in Table 6 of this preamble, the San Joaquin Valley area needs to
reduce NOX and direct PM2.5 emission levels by a
total of 63.7% and 10.2%, respectively, from 2013 base year levels in
order to attain the 2006 PM2.5 NAAQS by the end of 2024.
    As part of their respective control measure commitments in the SJV
PM2.5 Plan, CARB and the District each have identified
potential control measures that are expected to achieve the additional
emissions reductions needed for attainment. The timeline needed to
develop, adopt, and implement these measures, however, goes well beyond
the December 31, 2019 serious area attainment date for the 2006
PM2.5 NAAQS in this area. Both the State and District are
making progress in adopting the rules and measures listed in their
respective control measure commitments but have not yet completely
fulfilled them. Given these circumstances, we find that the State's and
District's reliance on enforceable commitments in the SJV
PM2.5 Plan is warranted. Therefore, we have considered the
three factors the EPA uses to determine whether the use of enforceable
commitments in lieu of adopted measures satisfies CAA planning
requirements.
(a) The Commitment Represents a Limited Portion of Required Reductions
    For the first factor, we look to see if the commitment addresses a
limited portion of a statutory requirement, such as the amount of
emissions reductions needed to attain the NAAQS in a nonattainment
area. As shown in Table 9 of this preamble, most of the total emission
reductions needed to attain the 2006 PM2.5 NAAQS in the San
Joaquin Valley by the end of 2024 will be achieved through
implementation of both baseline and new measures, leaving 13.8% (28.0
tpd) of the necessary NOX reductions and 26.6% (1.7 tpd) of
the necessary direct PM2.5 reductions as aggregate tonnage
commitments.
    Given the nature of the PM2.5 challenge in the San
Joaquin Valley, the significant reductions in NOX and direct
PM2.5 emission levels achieved through implementation of
baseline measures over the past several decades, and the difficulty of
identifying additional control measures that are feasible for
implementation in the area, we find it reasonable for the State and
District to seek additional time to adopt the last increment of
emission reductions necessary for attainment by 2024.
    Therefore, we find that the emission reductions remaining as
enforceable commitments in the SJV PM2.5 Plan represent a
limited portion of the total emissions reductions needed to demonstrate
attainment by December 31, 2024.
(b) The State Is Capable of Fulfilling Its Commitment
    For the second factor, we consider whether the State and District
are capable of fulfilling their commitments. CARB and the District
recently provided updates on their progress in developing and adopting
the additional mobile source and stationary source measures listed in
their respective control measure commitments. Specifically, as shown in
Table 7 of this preamble, CARB has adopted four of the 12 regulatory
measures listed in its control measure commitment, including heavy-duty
vehicle opacity limits, heavy-duty vehicle warranty requirements,
Innovative Clean Transit, and Zero-Emission Airport Shuttle Buses. CARB
has also begun the public process on seven of the remaining eight
regulatory measures listed in CARB's control measure commitment.
Additionally, on December 12, 2019, CARB adopted the San Joaquin Valley
Agricultural Incentive Measure, one of the three incentive-based
measures identified in its control measure commitment. CARB submitted
this measure to the EPA on February 11, 2020, and the EPA has proposed
to approve it as a revision to the California SIP.\350\
---------------------------------------------------------------------------

    \350\ Letter dated February 11, 2020, from Richard Corey,
Executive Officer, CARB, to Mike Stoker, Regional Administrator, EPA
Region 9, and ``Air Plan Approval; California; San Joaquin Valley
Unified Air Pollution Control District'' (proposed rule to approve
``San Joaquin Valley Agricultural Equipment Incentive Measure''),
pre-publication notice signed February 13, 2020.

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    For CARB's Heavy Duty I/M Program, in addition to the February 11,
2019 workshop, CARB has held three other workshops in 2019.\351\ With
the passage of California Senate Bill 210, the Heavy Duty I/M Program
will be considered for Board action in 2020.\352\ For CARB's Heavy-Duty
Low-NOX Engine Standard, following the November 3, 2016
public workshop, CARB held six additional workshops between 2017 and
2019.\353\ For the Zero-Emission Airport Ground Support Equipment, CARB
held a workshop on August 2, 2018.\354\ For the Small Off-Road Engines
measure, CARB has held five additional working group meetings and three
public workshops between 2017 and 2019.\355\ For Transport
Refrigeration Units Used for Cold Storage, CARB held additional
workshops in 2017 and most recently in October 2019.\356\
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    \351\ Information about the proposed Heavy-Duty I/M Program is
available at https://ww2.arb.ca.gov/our-work/programs/inspection-and-maintenance-program/Meetings-and-Workshops.
    \352\ SB 210 was signed by the California Governor and filed
with the Secretary of State on September 20, 2019.
    \353\ Information about the proposed Heavy-Duty Low-
NOX Engine Standard is available at https://ww2.arb.ca.gov/our-work/programs/heavy-duty-low-nox/heavy-duty-low-nox-meetings-workshops.
    \354\ Information about the proposed Zero-Emission Airport
Ground Support Equipment regulation is available at https://ww2.arb.ca.gov/our-work/programs/zero-emission-airport-ground-support-equipment/ze-airport-gse-meetings-workshops.
    \355\ Information about the proposed Small Off-Road Engines
measure is available at https://ww2.arb.ca.gov/our-work/programs/small-off-road-engines-sore/resources and https://ww2.arb.ca.gov/sore-workshops.
    \356\ Information about the proposed Transport Refrigeration
Units Used for Cold Storage measure is available at https://ww2.arb.ca.gov/our-work/programs/transport-refrigeration-unit/tru-meetings-workshops.
---------------------------------------------------------------------------

    CARB continues to pursue additional control strategies to reduce
emissions in California's nonattainment areas. For example, ongoing
CARB programs that address zero emission airport shuttle buses and
transportation refrigeration units used for cold storage have yet to be
quantified but are expected to further reduce NOX and direct
PM2.5 emissions in the San Joaquin Valley by 2024.\357\
Additionally, as part of the development of a draft plan submission to
address attainment of the ozone NAAQS in the South Coast, CARB has
identified a number of potential new state control measures that would
achieve NOX and direct PM2.5 emission reductions
not only in the South Coast but also in the San Joaquin Valley.\358\
These include a Tier 5 non-road diesel engine standard, a state green
contracting measure, a measure to reduce single occupancy vehicle
travel, and a locomotive emission reduction measure.
---------------------------------------------------------------------------

    \357\ 2018 PM2.5 Plan, Chapter 4, Table 4-9.
    \358\ CARB, ``2019 South Coast 8-hour Ozone SIP Update,''
December 12, 2019. See also CARB Resolution 19-31 (December 12,
2019). Further information about this SIP revision is available at
https://ww3.arb.ca.gov/planning/sip/planarea/scabsip/scabsip.htm#2019o3.
---------------------------------------------------------------------------

    Similarly, the District has made progress in meeting its control
measure commitments for the San Joaquin Valley. As shown in Table 8 of
this preamble, following an initial December 2018 public workshop, the
District adopted amendments to Rule 4901 on June 20, 2019, and CARB
submitted the amended rule to the EPA on July 22, 2019.\359\ The
amendments to Rule 4901 include lowering the residential wood burning
curtailment thresholds for Madera, Fresno, and Kern Counties in
addition to Valley-wide rule enhancements. The EPA has proposed to
approve amended Rule 4901 into the California SIP.\360\
---------------------------------------------------------------------------

    \359\ Letter dated July 19, 2019, from Richard Corey, Executive
Officer, CARB, to Mike Stoker, Regional Administrator, EPA Region 9.
    \360\ 85 FR 1131.
---------------------------------------------------------------------------

    Additionally, the District has started a public process for five of
the remaining eight regulatory measures, including each of the five
regulatory measures for which it committed to do so by 2019 or earlier.
Specifically, on August 23, 2017, the District hosted an initial public
scoping meeting on potential amendments to Rule 4311 (``Flares''), and
on November 13, 2019, the District hosted a public workshop on
potential amendments to the rule.\361\ These potential amendments
include additional flare minimization requirements, where
technologically achievable and economically feasible, and additional
ultra-low NOX flare emission limitations for existing and
new flaring activities at Valley facilities, where technologically
achievable and economically feasible.
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    \361\ For more information on this workshop, see https://www.valleyair.org/Workshops/postings/2019/11-13-19_Flares/presentation.pdf.
---------------------------------------------------------------------------

    For the remaining four measures in the District's control measure
commitment, on June 21, 2018, the District adopted amendments to Rule
4692 that require commercial cooking operations with UFCs to report by
January 1, 2019, on the type and quantity, in pounds, of meat cooked on
the UFCs on a weekly basis for the previous 12-month period as well as
other information regarding the nature of their operations, and for
certain such operations to register with the District and keep weekly
records relating to the quantities of meat cooked. This is an important
first step in the District's development of a new control measure for a
source category not previously subject to direct PM2.5
emission control requirements in the San Joaquin Valley. The District
hosted a public scoping workshop for Rule 4692 on December 12,
2019,\362\ and a scoping meeting for Rule 4306 and Rule 4320 on
December 5, 2019.\363\ Finally, the District held a scoping meeting for
Rule 4702, also on December 5, 2019.\364\
---------------------------------------------------------------------------

    \362\ More information on the public scoping workshop on Rule
3692 can be found at https://www.valleyair.org/Workshops/postings/2019/12-12-19_CC/presentation.pdf.
    \363\ More information on the scoping workshop for Rules 4306
and 4320 can be found at https://www.valleyair.org/Workshops/postings/2019/12-05-19_BGH/presentation.pdf.
    \364\ Information on the scoping meeting on Rule 4702 can be
found at https://www.valleyair.org/Workshops/postings/2019/12-05-19_ICE/presentation.pdf.
---------------------------------------------------------------------------

    Beyond the rules discussed above, both CARB and the District have
well-funded incentive grant programs to reduce emissions from mobile,
stationary, and area sources in the San Joaquin Valley. Funding for the
State's incentive programs in the San Joaquin Valley comes from various
sources including the Carl Moyer Program, Proposition 1B Goods Movement
Emission Reduction Program, Greenhouse Gas Reduction Fund, and the
Funding Agricultural Replacement Measures for Emission Reductions
(FARMER) program.\365\ Funding for the District's incentive programs
comes from a combination of federal, State, and local funding
mechanisms, including the Diesel Emission Reduction Act (DERA) and
Target Airshed Grant programs, the Carl Moyer Program, and fees
assessed in the San Joaquin Valley by the California Department of
Motor Vehicles and by the District through programs for Indirect Source
Review, Voluntary Emission Reduction Agreements, and large boilers,
steam generators, and process heaters.\366\
---------------------------------------------------------------------------

    \365\ 2018 PM2.5 Plan, App. E, E-6.
    \366\ Id.
---------------------------------------------------------------------------

    Collectively, these incentive funds have been applied to a wide
range of emission sources, including heavy-duty trucks, light-duty
vehicles, mobile agricultural equipment, locomotives, school buses,
alternative fuel infrastructure, community-based programs, agricultural
irrigation pumps, residential wood combustion devices, and commercial
charbroilers.\367\ The Plan identifies the total funding need for
expeditious attainment as $5 billion, including $3.3 billion for heavy-
duty trucks and buses and $1.4 billion for mobile agricultural
equipment.\368\
---------------------------------------------------------------------------

    \367\ Id. at App. E, E-8 to E-21.
    \368\ Id. at App. E, Table E-4 (``Incentive Funding Needed for
Expeditious Attainment''). The CARB Staff Report describes the
status of current incentive funding and CARB's expectations
concerning future incentive funding out to 2024 for the San Joaquin
Valley. CARB Staff Report, section F (``Status of Incentive
Funding''), 24-27.

---------------------------------------------------------------------------

    We note that, during CARB's September 19, 2019 hearing on the SJV
PM2.5 Plan, community and environmental advocacy groups
raised concerns that incentive funding recently appropriated fell short
of the Plan's needs and requested that the State pursue alternative
measures to obtain emission reductions from specific stationary sources
in the San Joaquin Valley.\369\ In response to these concerns and
similar concerns raised by CARB Governing Board Member Dean Florez,
CARB committed to follow-up with the District and stakeholders and to
hold public workshops in the San Joaquin Valley to discuss additional
emission reduction opportunities.\370\
---------------------------------------------------------------------------

    \369\ Letter dated September 17, 2019, from Genevieve Gale,
Central Valley Air Quality (CVAQ) Coalition, et al to CARB Board
Members and Staff.
    \370\ J&K Court Reporting, LLC, ``Meeting, State of California
Air Resources Board,'' September 19, 2019 (transcript of CARB's
public hearing), 100.
---------------------------------------------------------------------------

    We note also that the State and District will have to submit to the
EPA, for SIP approval, any control measure that it intends to rely on
to satisfy the aggregate tonnage commitments in the Plan. Where the
State or District intends to substitute reductions in one pollutant to
achieve a tonnage commitment concerning a different pollutant (e.g.,
substituting NOX reductions to satisfy a direct
PM2.5 reduction commitment), it must include an appropriate
inter-pollutant trading (IPT) ratio and the technical basis for such
ratio. The EPA will review any such IPT ratio and its bases before
approving or disapproving the measure.
    Given the evidence of the State's and District's progress to date
in proposing and adopting the measures listed in their respective
control measure commitments and their continuing efforts to develop
additional control measures to further reduce NOX and
PM2.5 emissions in the San Joaquin Valley, we find that the
State and District are capable of meeting their commitments.
(c) The Commitment Is for a Reasonable and Appropriate Timeframe
    For the third and last factor, we consider whether the commitment
is for a reasonable and appropriate period of time. As discussed in
section II.B of this preamble, on March 23, 2017, CARB adopted the 2016
State Strategy and directed staff to return to the Board with a
commitment to achieve additional emission reductions from mobile
sources in the San Joaquin Valley.\371\ CARB responded by developing
the Valley State SIP Strategy, which includes additional state
commitments to achieve accelerated emission reductions for purposes of
attaining the PM2.5 NAAQS in the San Joaquin Valley.
---------------------------------------------------------------------------

    \371\ CARB Resolution 17-7 (March 23, 2017), page 7.
---------------------------------------------------------------------------

    In the Valley State SIP Strategy, CARB recognized that the earlier
attainment dates for the 1997, 2006, and 2012 PM2.5 NAAQS in
the San Joaquin Valley compared to ozone attainment dates in the San
Joaquin Valley and elsewhere in the State required accelerating the
pace of NOX reductions.\372\ Thus, in the Valley State SIP
Strategy CARB identified and committed to achieve emission reductions
of 32 tpd of NOX and 0.9 tpd of direct PM2.5 by
2024,\373\ significantly greater amounts than those CARB had committed
to in the 2016 State Strategy (6 tpd of NOX and 0.1 tpd of
direct PM2.5 by 2025).\374\ CARB defined the estimate of
emission reductions by 2024 from the lower in-use performance level of
heavy-duty trucks as 6.8 tpd of NOX, representing the
largest emission reduction among the additional prohibitory
measures.\375\
---------------------------------------------------------------------------

    \372\ Valley State SIP Strategy, 2-3 and 6.
    \373\ CARB Resolution 18-49 (October 25, 2018), page 5.
    \374\ CARB Resolution 17-7 (March 23, 2017), paragraph 7.
    \375\ 2018 PM2.5 Plan, Ch. 4, Table 4-9.
---------------------------------------------------------------------------

    The SJV PM2.5 Plan includes specific rule development,
adoption, and implementation schedules designed to meet the State's and
District's commitments to reduce emissions to the levels needed to
attain the 2006 PM2.5 NAAQS in the San Joaquin Valley by
2024. For example, the aggregate commitments in the SJV
PM2.5 Plan include commitments by both the State and the
District to begin the public process on each of their respective
control measure commitments by specific dates ranging from 2015 to
2021. The commitments also identify action and implementation dates
ranging from 2018 to 2024 for a number of State and District control
measures, including amendments to SJVUAPCD Rule 4901, Rule 4311, Rule
4306, Rule 4320, Rule 4354, and Rule 4352.\376\
---------------------------------------------------------------------------

    \376\ 2018 PM2.5 Plan, Ch. 4, Tables 4-4, 4-5, and 4-
8.
---------------------------------------------------------------------------

    We find that these schedules provide a reasonable and appropriate
amount of time for the State and District to achieve the remaining
emission reductions necessary to the attain the 2006 24-hour
PM2.5 NAAQS in the San Joaquin Valley by December 31, 2024.
We therefore conclude that the third factor is satisfied.
c. Conclusion
    The EPA must make several findings in order to approve the modeled
attainment demonstration in an attainment plan SIP submission. First,
we must find that the attainment demonstration's technical bases,
including the emissions inventories and air quality modeling, are
adequate. As discussed in sections IV.A and IV.D.4.a of this preamble,
we are proposing to approve both the emissions inventories and the air
quality modeling on which the SJV PM2.5 Plan's attainment
demonstration and related provisions are based.
    Second, we must find that the SIP submittal provides for
expeditious attainment through the timely implementation of all BACM
and BACT. As discussed in section IV.C of this preamble, we are
proposing to approve the BACM/BACT demonstration in the SJV
PM2.5 Plan.
    Third, the EPA must find that the emissions reductions that are
relied on for attainment in the SIP submission are creditable. As
discussed in section IV.D.4, the SJV PM2.5 Plan relies
principally on already adopted and approved rules to achieve the
emissions reductions needed to attain the 2006 24-hour PM2.5
standards in the San Joaquin Valley by December 31, 2024. The balance
of the reductions is currently in the form of enforceable commitments
that account for 13.8% of the NOX and 26.6% of the direct
PM2.5 emissions reductions needed for attainment, as shown
in Table 9 of this preamble.
    The EPA has previously accepted enforceable commitments in lieu of
adopted control measures in attainment demonstrations when the
circumstances warrant it and the commitments meet three criteria. As
discussed herein, we find that circumstances here warrant the
consideration of enforceable commitments and that the three criteria
are met: (1) The commitments constitute a limited portion of the
required emissions reductions, (2) both the State and the District have
demonstrated their capability to meet their commitments, and (3) the
commitments are for an appropriate timeframe. We therefore propose to
allow the State to rely on these enforceable commitments in its
attainment demonstration.
    Based on these evaluations, we propose to determine that the SJV
PM2.5 Plan provides for attainment of the 2006 24-hour
PM2.5 NAAQS by the most expeditious alternative date
practicable, consistent with the requirements of CAA sections
189(b)(1)(A) and 188(e).

5. Application for an Attainment Date Extension
    As discussed in section I of this preamble, the Serious area
attainment date for the San Joaquin Valley for the 2006 24-hour
PM2.5 NAAQS under CAA section 188(c)(2) is December 31,
2019. The first criterion for an extension of the attainment date
beyond this statutory attainment date is that the State must apply for
such extension. In the SJV PM2.5 Plan, CARB and SJVUAPCD
submitted a complete application for an extension of the Serious area
attainment date for the SJV to December 31, 2024, for the 2006
PM2.5 NAAQS.\377\ In accordance with the requirements of the
PM2.5 SIP Requirements Rule in 40 CFR 51.1005(b)(2), the SJV
PM2.5 Plan contains all of the required components of a
Serious area plan containing a request for extension of the attainment
date under CAA section 188(e), as follows: (1) Base year and attainment
projected emissions inventories, (2) provisions to implement MSM and
BACM, (3) a modeled attainment demonstration, (4) reasonable further
progress provisions, (5) quantitative milestone provisions, (6)
contingency measure provisions, and (7) nonattainment new source review
plan provisions.\378\
---------------------------------------------------------------------------

    \377\ CARB Resolution 19-1 (January 24, 2019), (submitting the
Plan to EPA as a SIP revision), SJVUAPCD Governing Board Resolution
18-11-16 (November 15, 2018), paragraph 1 (adopting the 2018
PM2.5 Plan), and 2018 PM2.5 Plan, Ch. 6, 6-1
to 6-2.
    \378\ Letter dated May 9, 2019, from Richard Corey, Executive
Officer, CARB, to Mike Stoker, Regional Administrator, EPA Region 9
(transmitting adopted SJV PM2.5 Plan) and letter dated
November 15, 2019, from Richard Corey, Executive Officer, CARB, to
Mike Stoker, Regional Administrator, EPA Region 9 (transmitting
adopted nonattainment new source review rules for the San Joaquin
Valley).
---------------------------------------------------------------------------

    Based on our evaluation of the Plan, we propose to grant the
State's request to extend the Serious area attainment deadline from
December 31, 2019, to December 31, 2024, for the 2006 PM2.5
NAAQS in the San Joaquin Valley. We are requesting public comment to
ensure that the EPA fully considers all relevant factors in evaluating
the State's request. If based on new information or public comments we
find that a decision to grant the requested extension would not be
consistent with the requirements of the Act, the EPA may reconsider
this proposal or deny California's request to extend the deadline.\379\
---------------------------------------------------------------------------

    \379\ Under CAA section 179(c), the EPA must determine no later
than 6 months after the applicable attainment date for any
nonattainment area whether the area attained the NAAQS by that date.
Absent an extension of the Serious area attainment date under CAA
section 188(e), the latest permissible attainment date for the 2006
PM2.5 NAAQS in the San Joaquin Valley Serious
nonattainment area was December 31, 2019, and the statutory deadline
under CAA section 179(c) for the EPA to determine whether the area
attained these NAAQS by the Serious area attainment date is June 30,
2020. See also Memorandum dated November 14, 1994, from Sally L.
Shaver, EPA Air Quality Strategies and Standards Division, to EPA
Air Division directors, Regions I through X, RE: ``Criteria for
Granting 1-Year Extensions of Moderate PM-10 Nonattainment Area
Attainment Dates, Making Attainment Determinations, and Reporting on
Quantitative Milestones,'' 16 (stating that EPA regional offices
will address state requests for 1-year attainment date extensions
under CAA section 188(d) no later than 6 months after the applicable
attainment date). The CAA does not establish a specific deadline for
the EPA's denial of a request for extension of an attainment date.
---------------------------------------------------------------------------

    If the EPA were to take final action to deny the request for
extension of the attainment date, the EPA would be required under CAA
section 179(c) to determine, based on the San Joaquin Valley's air
quality as of December 31, 2019, whether the area attained the 2006
PM2.5 NAAQS by that date.

E. Reasonable Further Progress and Quantitative Milestones

1. Statutory and Regulatory Requirements
    Section 172(c)(2) of the Act provides that all nonattainment area
plans shall require reasonable further progress (RFP) toward
attainment. In addition, CAA section 189(c) requires that all
PM2.5 nonattainment area plans contain quantitative
milestone for purposes of measuring RFP, as defined in CAA section
171(1), every three years until the area is redesignated to attainment.
Section 171(1) of the Act defines RFP as the annual incremental
reductions in emissions of the relevant air pollutant as are required
by part D, title I of the Act, or as may reasonably be required by the
Administrator for the purpose of ensuring attainment of the NAAQS by
the applicable attainment date. Neither subpart 1 nor subpart 4 of part
D, title I of the Act requires that states achieve a set percentage of
emissions reductions in any given year for purposes of satisfying the
RFP requirement.
    For purposes of the particulate matter NAAQS, RFP has historically
been met by showing annual incremental emissions reductions sufficient
to maintain ``generally linear progress'' toward attainment by the
applicable deadline.\380\ As discussed in EPA guidance in the General
Preamble Addendum, requiring generally linear progress in reductions of
direct PM2.5 and relevant PM2.5 precursors in a
PM2.5 attainment plan may be appropriate in situations
where:
---------------------------------------------------------------------------

    \380\ General Preamble Addendum, 42015.
---------------------------------------------------------------------------

     The pollutant is emitted by a large number and range of
sources,
     the relationship between any individual source or source
category and overall air quality is not well known,
     a chemical transformation is involved (e.g., secondary
particulate significantly contributes to PM2.5 levels over
the standard), and/or
     the emission reductions necessary to attain the
PM2.5 standards are inventory-wide.\381\
---------------------------------------------------------------------------

    \381\ Id.
---------------------------------------------------------------------------

    The EPA believes that the facts and circumstances of each specific
area will be relevant to whether the emissions reductions meet the
agency's expectations for generally linear progress.\382\
---------------------------------------------------------------------------

    \382\ 81 FR 58010, 15386.
---------------------------------------------------------------------------

    The General Preamble Addendum also indicates that requiring
generally linear progress may be less appropriate in other situations,
such as:
     Where there are a limited number of sources of direct
PM2.5 or a relevant precursor,
     where the relationships between individual sources and air
quality are relatively well defined, and/or
     where the emission control systems utilized (e.g., at
major point sources) will result in swift and dramatic emission
reductions.
    In nonattainment areas characterized by any of these latter
conditions, the EPA has recommended that RFP may be met by stepwise
progress as controls are implemented and achieve significant reductions
soon thereafter. For example, if an area's nonattainment problem can be
attributed to a few major stationary sources, EPA guidance recommends
that states may meet RFP by ``adherence to an ambitious compliance
schedule'' that is likely to yield significant reductions of direct
PM2.5 or a PM2.5 precursor on a periodic basis,
rather than on a generally linear basis.\383\ The EPA believes that the
facts and circumstances of each specific area will be relevant to
whether the emissions reductions meet the agency's expectations for
stepwise progress.
---------------------------------------------------------------------------

    \383\ Id.
---------------------------------------------------------------------------

    Plans for PM2.5 nonattainment areas should include
detailed schedules for compliance with emission control measures in the
area and provide corresponding annual emission reductions to be
achieved by each milestone in the schedule.\384\ In reviewing an
attainment plan under subpart 4, the EPA considers whether the annual
incremental emissions reductions to be achieved are reasonable in light
of the statutory objective of timely attainment. Although early

implementation of the most cost-effective control measures is often
appropriate, states should consider both cost-effectiveness and
pollution reduction effectiveness when developing implementation
schedules for control measures, and may implement measures that are
more effective at reducing PM2.5 earlier to provide greater
public health benefits.\385\
---------------------------------------------------------------------------

    \384\ Id. at 42016.
    \385\ Id.
---------------------------------------------------------------------------

    In addition to the EPA's longstanding guidance on the RFP
requirements, the Agency has established specific regulatory
requirements in the PM2.5 SIP Requirements Rule for purposes
of satisfying the Act's RFP requirements and provided related guidance
in the preamble to the rule. Specifically, under the PM2.5
SIP Requirements Rule, each PM2.5 attainment plan must
contain an RFP analysis that includes, at minimum, the following four
components: (1) An implementation schedule for control measures; (2)
RFP projected emissions for direct PM2.5 and all
PM2.5 plan precursors for each applicable milestone year,
based on the anticipated control measure implementation schedule; (3) a
demonstration that the control strategy and implementation schedule
will achieve reasonable progress toward attainment between the base
year and the attainment year; and (4) a demonstration that by the end
of the calendar year for each triennial milestone date for the area,
pollutant emissions will be at levels that reflect either generally
linear progress or stepwise progress in reducing emissions on an annual
basis between the base year and the attainment year.\386\
---------------------------------------------------------------------------

    \386\ 40 CFR 51.1012(a).
---------------------------------------------------------------------------

    A state intending to meet the RFP requirement on a stepwise basis
must provide an appropriate justification for the selected
implementation schedule.\387\ As the EPA explained in the preamble to
the PM2.5 SIP Requirements Rule, a plan that relies on a
stepwise approach to meeting RFP should include ``a clear rationale and
supporting information to explain why generally linear progress is not
appropriate (e.g., due to the nature of the nonattainment problem, the
types of sources contributing to PM2.5 levels in the area
and the implementation schedule for control requirements at such
sources).'' \388\ Additionally, states should estimate the RFP
projected emissions for each quantitative milestone year by sector on a
pollutant-by-pollutant basis.\389\
---------------------------------------------------------------------------

    \387\ 40 CFR 51.1012(a)(4).
    \388\ 81 FR 58010, 58057.
    \389\ 81 FR 58010, 58056.
---------------------------------------------------------------------------

    Section 189(c) of the Act requires that PM2.5 attainment
plans include quantitative milestones that demonstrate RFP. The purpose
of the quantitative milestones is to allow periodic evaluation of the
area's progress towards attainment of the PM2.5 NAAQS
consistent with RFP requirements. Because RFP is an annual emission
reduction requirement and the quantitative milestones are to be
achieved every three years, when a state demonstrates compliance with
the quantitative milestone requirement, it should also demonstrate that
RFP has been achieved during each of the relevant three years.
Quantitative milestones should provide an objective means to evaluate
progress toward attainment meaningfully, e.g., through imposition of
emissions controls in the attainment plan and the requirement to
quantify those required emissions reductions. The CAA also requires a
state to submit, within 90 days after each three-year quantitative
milestone date, a milestone report that includes technical support
sufficient to document completion statistics for appropriate
milestones, e.g., the calculations and any assumptions made concerning
emission reductions to date.\390\
---------------------------------------------------------------------------

    \390\ General Preamble Addendum, 42016, 42017.
---------------------------------------------------------------------------

    The CAA does not specify the starting point for counting the three-
year periods for quantitative milestones under CAA section 189(c). In
the General Preamble and General Preamble Addendum, the EPA interpreted
the CAA to require that the starting point for the first three-year
period be the due date for the Moderate area plan submission.\391\ In
keeping with this historical approach, the EPA established December 31,
2014, the deadline that the EPA established for a state's submission of
any additional attainment-related SIP elements necessary to satisfy the
subpart 4 Moderate area requirements for the 2006 24-hour
PM2.5 NAAQS, as the starting point for the first three-year
period under CAA section 189(c) for the 2006 PM2.5 NAAQS in
the San Joaquin Valley.\392\
---------------------------------------------------------------------------

    \391\ General Preamble, 13539, and General Preamble Addendum,
42016.
    \392\ 79 FR 31566 (June 2, 2014) (final rule establishing
subpart 4 moderate area classifications and deadline for related SIP
submissions). Although this final rule did not affect any action
that the EPA had previously taken under CAA section 110(k) on a SIP
for a PM2.5 nonattainment area, the EPA noted that states
may need to submit additional SIP elements to fully comply with the
applicable requirements of subpart 4, even for areas with previously
approved PM2.5 attainment plans, and that the deadline
for any such additional plan submissions was December 31, 2014. Id.
at 31569.
---------------------------------------------------------------------------

    Under the PM2.5 SIP Requirements Rule, each attainment
plan submission for an area designated nonattainment for the 2006
PM2.5 NAAQS before January 15, 2015, must contain
quantitative milestones to be achieved no later than three years after
December 31, 2014, and every three years thereafter until the milestone
date that falls within three years after the applicable attainment
date.\393\ If the area fails to attain, this post-attainment date
milestone provides the EPA with the tools necessary to monitor the
area's continued progress toward attainment while the state develops a
new attainment plan under CAA section 189(d).\394\ Quantitative
milestones must provide for objective evaluation of reasonable further
progress toward timely attainment of the PM2.5 NAAQS in the
area and include, at minimum, a metric for tracking progress achieved
in implementing SIP control measures, including BACM and BACT, by each
milestone date.\395\
---------------------------------------------------------------------------

    \393\ 40 CFR 51.1013(a)(4).
    \394\ 81 FR 58010, 58064.
    \395\ Id. at 58064 and 58092.
---------------------------------------------------------------------------

    Because the EPA designated the San Joaquin Valley as a
nonattainment area for the 2006 24-hour PM2.5 NAAQS
effective December 14, 2009,\396\ the plan for this area must contain
quantitative milestones to be achieved no later than three years after
December 31, 2014, and every three years thereafter until the milestone
date that falls within three years after the applicable attainment
date.\397\ The SJV PM2.5 Plan contains a request by the
State under CAA section 188(e) to extend the applicable attainment date
for the 2006 24-hour PM2.5 NAAQS in the San Joaquin Valley
to December 31, 2024. Therefore, in accordance with 40 CFR
51.1013(a)(4), the Serious area plan for this area must contain
quantitative milestones to be achieved no later than December 31, 2017,
December 31, 2020, December 31, 2023, and December 31, 2026.
---------------------------------------------------------------------------

    \396\ 74 FR 58688 (November 13, 2009).
    \397\ 40 CFR 51.1013(a)(4).
---------------------------------------------------------------------------

2. Summary of State's Submission
    Appendix H (``RFP, Quantitative Milestones, and Contingency'') of
the 2018 PM2.5 Plan contains the State's RFP demonstration
and quantitative milestones for the 2006 24-hour PM2.5
NAAQS. Following the identification of a transcription error in the RFP
tables of Appendix H, the State submitted a revised version of Appendix
H that corrects the transcription error and provides additional
information on the RFP demonstration.\398\ Given the State's

conclusions that ammonia, SOX, and VOC emissions do not
contribute significantly to PM2.5 levels that exceed the
2006 PM2.5 NAAQS in the San Joaquin Valley, as discussed in
section IV.B of this preamble, the RFP demonstration provided by the
State addresses emissions of direct PM2.5 and
NOX.\399\ Similarly, the State developed quantitative
milestones based upon the Plan's control strategy measures that achieve
emission reductions of direct PM2.5 and NOX.\400\
For the 2006 PM2.5 NAAQS, the RFP demonstration in the Plan
follows a stepwise approach due to the time required for CARB and the
District ``to amend rules, develop programs, and implement the emission
reduction measures.'' \401\ The revised Appendix H provides clarifying
information on the RFP demonstration, including additional information
to justify the Plan's stepwise approach to demonstrating RFP. This
clarifying information did not affect the Plan's quantitative
milestones.
---------------------------------------------------------------------------

    \398\ Appendix H to 2018 PM2.5 Plan, submitted
February 11, 2020 via the EPA State Planning Electronic
Collaboration System. This revised version of Appendix H replaces
the version submitted with the 2018 PM2.5 Plan on May 10,
2019. All references to Appendix H in this proposed rule are to the
revised version of Appendix H submitted February 11, 2020.
    \399\ 2018 PM2.5 Plan, App. H, H-1.
    \400\ Id. at H-22 to H-23 (for State milestones) and H-19 to H-
20 (for District milestones).
    \401\ 2018 PM2.5 Plan, App. H, H-4.
---------------------------------------------------------------------------

    We describe the RFP demonstration and quantitative milestones in
the SJV PM2.5 Plan in greater detail below.
a. Reasonable Further Progress
    The State addressed the RFP and quantitative milestone requirements
in Appendix H to the 2018 PM2.5 Plan submitted in February
2020. The Plan estimates that emissions of direct PM2.5 and
NOX will generally decline from the 2013 base year to the
projected 2024 attainment year, and beyond to the 2026 quantitative
milestone year. The Plan's emissions inventory shows that direct
PM2.5 and NOX are emitted by a large number and
range of sources in the San Joaquin Valley. Table H-2 in Appendix H
contains an anticipated implementation schedule for District regulatory
control measures and Table 4-8 in Chapter 4 of the 2018
PM2.5 Plan contains an anticipated implementation schedule
for CARB control measures in the San Joaquin Valley. Table H-5 in
Appendix H (reproduced in Table 10) contains projected emissions for
each quantitative milestone year and the attainment year. These
emission levels reflect both baseline emissions projections and
commitments to achieve additional emission reductions through
implementation of new control measures beginning in 2024.\402\
---------------------------------------------------------------------------

    \402\ In App. H, see Tables H-3 (emission projections based on
baseline measures) and H-4 (reductions from control measure
commitments). The SJV PM2.5 Plan includes commitments for
reductions from new control measures in 2024 and 2025. With respect
to the projected emission reductions for 2026, the District and CARB
stated in a conversation with EPA staff on January 6, 2020 that they
assumed reductions achieved in 2026 would be similar to reductions
committed to in 2024 and 2025. See memorandum dated January 6, 2020,
from Laura Lawrence, EPA Region IX Air Planning Office, to docket
number EPA-R09-OAR-2019-0318.

       Table 10--PM2.5 Projected Emissions Inventory for Base and Milestone Years, Including Baseline Measures and Emission Reduction Commitments
                                                                  [Annual average tpd]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               2013            2017            2020            2023            2024            2026
                                                         -----------------------------------------------------------------------------------------------
                        Pollutant                                          Quantitative    Quantitative    Quantitative     Attainment     Quantitative
                                                           Baseline year     milestone       milestone       milestone         year          milestone
--------------------------------------------------------------------------------------------------------------------------------------------------------
PM2.5...................................................            62.5            58.9            59.0            58.3            56.1            56.2
NOX.....................................................           317.2           233.3           203.3           153.6           115.0           105.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: 2018 PM2.5 Plan, Appendix H, Table H-5.

    Table H-6 and Table H-7 of Appendix H (reproduced in Table 11)
identify the reductions needed for attainment of the 2006
PM2.5 NAAQS by 2024, and the San Joaquin Valley's progress
toward attainment in each milestone year.

                                     Table 11--Reductions Needed for Attainment and Achieved in Each Milestone Year
                                                                    [Annual average]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Percent reductions achieved in milestone year
                                                            Reductions   -------------------------------------------------------------------------------
                                                            needed for         2017            2020            2023            2024          2026 \a\
                        Pollutant                           attainment   -------------------------------------------------------------------------------
                                                            (from 2013     Quantitative    Quantitative    Quantitative                    Quantitative
                                                             baseline)       milestone       milestone       milestone      Attainment       milestone
                                                               (tpd)         (percent)       (percent)       (percent)    year (percent)     (percent)
--------------------------------------------------------------------------------------------------------------------------------------------------------
PM2.5...................................................             6.4            56.3            54.7            65.6             100            98.4
NOX.....................................................           202.2            41.5            56.3            81.0             100           104.7
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: 2018 PM2.5 Plan, Appendix H, Tables H-6 and H-7.
\a\ The EPA has made minor corrections to the calculated percentages for 2026 in Table H-7 of the 2018 PM2.5 Plan.

    Based on the data in Tables 10 and 11, the State and District set
RFP targets for the attainment year and quantitative milestone years as
shown in Table H-10 of Appendix H (reproduced in Table 12). The targets
are consistent with a stepwise approach to demonstrating RFP. For
direct PM2.5, significant reductions between the 2013
baseline and the 2017 milestone year (approximately 56% of the
reductions needed for attainment) are consistent with a generally
linear approach to demonstrating RFP. However, between the 2017 and
2020 milestone years, projected direct PM2.5 emissions
increase. Emissions of direct PM2.5 decrease by the 2023
milestone year but fall short of the rate of reductions that would show
generally linear

progress.\403\ The Plan relies on a more substantial direct
PM2.5 emission reduction in 2024 due, in large part, to the
State's and District's commitments to achieve additional
PM2.5 emission reductions from new measures in 2024. Direct
PM2.5 emissions are projected to increase slightly in 2026.
---------------------------------------------------------------------------

    \403\ To show generally linear progress, direct PM2.5
emissions would need to decrease by approximately 64% from the
baseline year in 2020, and by approximately 91% from the baseline
year in 2023. The actual decreases for these years are 55% in 2020,
and 66% in 2023.
---------------------------------------------------------------------------

    For NOX, the emission projections show steady reductions
over time. The projection for the 2017 milestone year is consistent
with a generally linear RFP demonstration, but for the 2020 and 2023
milestone years, emission reductions fall short of generally linear
progress toward attainment.\404\ The Plan relies on a more substantial
NOX emission reduction in 2024 due, in large part, to the
State's and District's commitments to achieve additional NOX
reductions from new measures that year. NOX emissions are
projected to continue to decrease in the 2026 milestone year.
---------------------------------------------------------------------------

    \404\ To show generally linear progress, NOX
emissions would need to decrease by approximately 64% from the
baseline year in 2020, and by approximately 91% from the baseline
year in 2023. The actual decreases for these years are 56% in 2020,
and 81% in 2023.
---------------------------------------------------------------------------

    According to the Plan, reductions in both direct PM2.5
and NOX emissions from 2013 base year levels result in
emissions levels consistent with attainment in the 2024 attainment
year. Based on these analyses, the State and District conclude that the
adopted control strategy and additional commitments for reductions from
new control programs beginning in 2024 are adequate to meet the RFP
requirement for the 2006 PM2.5 NAAQS.

                                         Table 12--Stepwise RFP Target Emission Levels and Projected Emission Levels for Milestone and Attainment Years
                                                                                [Annual average tpd]
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          2017                      2020                      2023                    2024 \a\                    2026
                           Pollutant                           ---------------------------------------------------------------------------------------------------------------------------------
                                                                   Target     Projected      Target     Projected      Target     Projected      Target     Projected    Target \b\   Projected
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
PM2.5.........................................................         58.9         58.9         59.0         59.0         58.3         58.3         56.1         56.1         56.2         56.2
NOX...........................................................        233.3        233.3        203.3        203.3        153.6        153.6        115.0        115.0        105.5        105.5
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Source: 2018 PM2.5 Plan, Appendix H, Tables H-6 and H-10.
\a\ Emissions targets and projections for the 2024 attainment year are provided in Table H-6 of the 2018 PM2.5 Plan.
\b\ Direct PM2.5 emissions for 2026 are derived from the Plan's projected emissions inventory (including baseline controls), less the 2.2 tpd of direct PM2.5 emissions that CARB and the
  District committed to achieve by 2024. 2018 PM2.5 Plan, Appendix H, Tables H-3, H-4, and H-5.

    The State and District's control strategy for attaining the 2006
PM2.5 NAAQS relies primarily on ongoing reductions from
baseline measures, recent revisions to the District's residential wood
burning rule (Rule 4901), and an aggregate tonnage commitment for the
remaining reductions needed for attainment. The majority of the
NOX and PM2.5 reductions needed for attainment
result from CARB's current mobile source control program. As shown in
Table 11, the attainment control strategy in the Plan is projected to
achieve a total of 202.2 tpd of NOX reductions by 2024, of
which 78% (157 tpd) is attributed to CARB's mobile source control
program.\405\ Similarly, the attainment control strategy is projected
to achieve a total of 6.4 tpd of direct PM2.5 reductions by
2024, of which 72% (4.6 tpd) is attributed to CARB's mobile source
control program.\406\ These on-going controls will thus result in
additional reductions in NOX and direct PM2.5
emissions between the base year (2013) and the attainment year
(2024).\407\
---------------------------------------------------------------------------

    \405\ Id. at Chapter 4, Table 4-7.
    \406\ Id.
    \407\ Id. at App. H, H-4.
---------------------------------------------------------------------------

    CARB's mobile source control program provides significant ongoing
reductions in emissions of direct PM2.5 and NOX
from on-road and non-road mobile sources such as light duty vehicles,
heavy-duty trucks and buses, non-road equipment, and fuels. For on-road
and non-road mobile sources, which represent the largest sources of
NOX emissions in the San Joaquin Valley, Appendix H of the
2018 PM2.5 Plan identifies five mobile source regulations
and control programs that limit emissions of direct PM2.5
and NOX: The On-Road Heavy-Duty Diesel Vehicles (In-Use)
Regulation (``Truck and Bus Regulation''), the Advanced Clean Cars
Program (``ACC Program''), the In-Use Off-Road Diesel-Fueled Fleets
Regulation (``Off-Road Regulation''), the Heavy-Duty Vehicle Inspection
and Maintenance Program, and the California Low-NOX Engine
Standard for new on-road heavy-duty engines used in medium- and heavy-
duty trucks purchased in California.\408\ CARB's mobile source BACM and
MSM analysis in Appendix D of the 2018 PM2.5 Plan provides a
more comprehensive overview of each of these programs and regulations,
among many others.\409\ CARB's emission projections for mobile sources
are presented in the Plan's emissions inventory.\410\
---------------------------------------------------------------------------

    \408\ 2018 PM2.5 Plan, App. H, H-21 and H-22. Because
the second phase of the Advanced Clean Cars Program (``ACC 2'') is
not scheduled for implementation until 2026 (see 2018
PM2.5 Plan, Table 4-8), which is after the January 1,
2024 implementation deadline under 40 CFR 51.1011(b)(5) for control
measures necessary for attainment by December 31, 2024, we are not
reviewing this program as part of the control strategy in the SJV
PM2.5 Plan.
    \409\ 2018 PM2.5 Plan, App. D, Ch. IV.
    \410\ 2018 PM2.5 Plan, App. B.
---------------------------------------------------------------------------

    The Truck and Bus Regulation, first adopted in 2008 and amended in
2011, has rolling compliance deadlines based on truck engine model year
(MY). CARB's implementation of the Truck and Bus Regulation includes
phase-in requirements for PM2.5 and NOX emissions
reductions that began in 2012 and require nearly all pre-2010 vehicles
to have exhaust emissions meeting 2010 MY engine emission levels by
2023.\411\ The 2010 MY engines include particulate filters for direct
PM2.5 control. By 2016, the particulate filter requirement
for trucks with a gross vehicle weight rating greater than 26,001
pounds was fully implemented in the San Joaquin Valley and all heavier
trucks with 1995 and older model year engines were required to have a
2010 engine installed or replaced by a truck with a 2010 MY
engine.\412\
---------------------------------------------------------------------------

    \411\ The State's quantitative milestone report for the 2017
milestone indicates that the requirement for heavier trucks to
install diesel particulate filters was fully implemented by 2016.
CARB and SJVUAPCD, ``2017 Quantitative Milestone Report for the 1997
and 2006 NAAQS,'' November 21, 2018 (``2017 QM Report''), 5.
    \412\ Id.
---------------------------------------------------------------------------

    For non-road vehicles, CARB adopted the Off-Road Regulation in 2007
to regulate vehicles used in construction, mining, and other industrial
applications. The Off-Road Regulation requires owners to (1) replace
older

engines or vehicles with newer, cleaner models, (2) retire older
vehicles or reduce their use, or (3) apply retrofit exhaust
controls.\413\ Beginning in 2014 for large fleets and in 2017 for
medium fleets, non-road fleets are required to meet increasingly
stringent fleet average indices over time.\414\ These indices reflect a
fleet's overall PM and NOX emissions rates by model year and
horsepower.
---------------------------------------------------------------------------

    \413\ 2017 QM Report, 8.
    \414\ A fleet average index is an indicator of a fleet's overall
emissions rate of particulate matter and NOX based on the
horsepower and model year of each engine in the fleet.
---------------------------------------------------------------------------

    The District has also adopted numerous stationary and area source
rules for direct PM2.5 and NOX emission sources
that are projected to contribute to RFP and attainment of the
PM2.5 standards. These include control measures for
stationary internal combustion engines, residential fireplaces, glass
manufacturing facilities, agricultural burning sources, and various
sizes of boilers, steam generators, and process heaters used in
industrial operations. Appendix H of the 2018 PM2.5 Plan
identifies stationary source regulatory control measures implemented by
the District that achieve ongoing PM2.5 and/or
NOX reductions through the Plan's RFP milestone years and
the attainment year, including the following: Rule 4354 (``Glass
Melting Furnaces''), Rule 4702 (Internal Combustion Engines''), and
Rule 4901 (``Wood Burning Fireplaces and Wood Burning Heaters'').\415\
---------------------------------------------------------------------------

    \415\ 2018 PM2.5 Plan, App. H, Table H-2.
---------------------------------------------------------------------------

    Rule 4354 was last amended in 2011 to lower certain limits on
emissions of NOX, SOX, and PM10 from
container glass, flat glass, and fiberglass manufacturing facilities.
Rule 4702 was last amended in 2013 to lower the NOX and
SOX emission limits for various types of internal combustion
engines rated at 25 brake horsepower or greater. The District most
recently amended Rule 4901 in 2019 to lower the thresholds at which
``No Burn'' days will be imposed to limit direct PM2.5
emissions from high-polluting wood burning heaters and fireplaces
during the November through February timeframe in three ``hot spot''
counties (Fresno, Kern, and Madera). These rules contribute to
incremental reductions in emission of direct PM2.5 and
NOX from the 2013 base year to the 2017 and 2020 RFP
milestone years.\416\ Additional District measures to control sources
of direct PM2.5 and NOX are also presented in the
Plan's BACM/MSM analyses and reflected in the Plan's baseline emission
projections.\417\
---------------------------------------------------------------------------

    \416\ 2017 QM Report, 2-3.
    \417\ 2018 PM2.5 Plan, App. B and App. C.
---------------------------------------------------------------------------

    For the remainder of the emission reductions necessary for
attainment, the SJV PM2.5 Plan identifies a series of
additional State and District commitments to achieve emission
reductions through additional control measures and incentive programs
that will contribute to attainment of the 2006 PM2.5 NAAQS
by 2024. For mobile sources, CARB's commitment identifies a list of 12
regulatory measures and three incentive-based measures that CARB has
committed to propose to its Board for consideration by specific
dates.\418\ For stationary and area sources, the District's commitment
identifies a list of nine regulatory measures and three incentive-based
measures that the District has committed to propose to its Board for
consideration by specific dates.\419\ Both CARB and the District have
committed to achieve specific amounts of reductions in direct
PM2.5 and NOX emissions by 2024, either through
implementation of these listed measures or through implementation of
other control measures that achieve the necessary amounts of emission
reductions by 2024.\420\
---------------------------------------------------------------------------

    \418\ 2018 PM2.5 Plan, Chapter 4, Table 4-8 and CARB
Resolution 18-49 (October 25, 2018), 5. Table 4-8 of the 2018
PM2.5 Plan lists 14 State regulatory measures but we are
excluding from our review the ``Advanced Clean Cars 2'' measure and
the ``Cleaner In-Use Agricultural Equipment'' measure, because these
measures are scheduled for implementation in 2026 and 2030,
respectively, well after the January 1, 2024 implementation deadline
for control measures necessary for attainment by December 31, 2024.
40 CFR 51.1011(b)(5).
    \419\ 2018 PM2.5 Plan, Chapter 4, Table 4-4 and
SJVUAPCD Governing Board Resolution 18-11-16 (November 15, 2018),
10-11.
    \420\ SJVUAPCD Governing Board Resolution 18-11-16 (November 15,
2018), 10-11 and CARB Resolution 18-49 (October 25, 2018), 5.
---------------------------------------------------------------------------

    The 2018 PM2.5 Plan discusses a number of additional
control measures that the District may adopt to meet its aggregate
tonnage commitment, including additional control requirements for
flares; boilers, steam generators, and process heaters of various
sizes; glass melting furnaces; internal combustion engines;
conservation management practices for agricultural operations; and
commercial under-fired charbroilers.\421\ In addition, the Plan states
that the District intends to use incentive programs to reduce emissions
of direct PM2.5 and NOX from internal combustion
engines used in agricultural operations, commercial under-fired
charbroilers, and residential woodburning devices.\422\ The 2018
PM2.5 Plan establishes deadlines between 2018 and 2023 for
CARB to take action on and begin implementing the 15 additional mobile
source control measures that CARB has committed to propose to its Board
\423\ and similar deadlines between 2019 and 2024 for the District to
take action on and begin implementing the 12 additional District
control measures that the District has committed to propose to its
Board.\424\
---------------------------------------------------------------------------

    \421\ 2018 PM2.5 Plan, Chapter 4, 4-12 and 4-15 to 4-
22.
    \422\ Id. at 4-22 to 4-24.
    \423\ 2018 PM2.5 Plan, Chapter 4, Table 4-8 and CARB
Resolution 18-49 (October 25, 2018), 5. The EPA is excluding two
State measures listed in Table 4-8 of the 2018 PM2.5
Plan, the ``Advanced Clean Cars 2'' measure and the ``Cleaner In-Use
Agricultural Equipment'' measure, because these measures are
scheduled for implementation in 2026 and 2030, respectively, well
after the January 1, 2024 implementation deadline for control
measures necessary for attainment by December 31, 2024. 40 CFR
51.1011(b)(5).
    \424\ 2018 PM2.5 Plan, Table 4-4 and Table 4-5 and
SJVUAPCD Governing Board Resolution 18-11-16 (November 15, 2018),
10-11.
---------------------------------------------------------------------------

    The anticipated implementation schedule for new District measures
is presented both in Table H-2 of Appendix H and in tables 4-4 and 4-5
of the 2018 PM2.5 Plan, and the anticipated implementation
schedule for new CARB measures is presented in Table 4-8 of the 2018
PM2.5 Plan. These anticipated implementation schedules are
summarized in Table 13, below. Although the commitment to achieve
reductions is based on an aggregate commitment for total reductions in
2024, the State and District anticipate implementing many of the
measures in Table 13 prior to these dates to achieve the aggregate
tonnage commitment.
    Specifically, implementation of the District's revisions to Rule
4901 (``Wood Burning Fireplaces and Wood Burning Heaters'') began in
2019, and implementation of CARB's lower opacity limits for heavy-duty
vehicles began in 2018. Additionally, the District anticipates
implementing several measures beginning in 2023 and CARB anticipates
implementing several measures in 2020, 2022, and 2023.\425\
---------------------------------------------------------------------------

    \425\ For more detail on our evaluation of the State's and
District's aggregate commitments, see section IV.D.4.b.ii of this
preamble.

  Table 13--Anticipated Implementation Schedule for State and District
                                Measures
------------------------------------------------------------------------
             CARB measures                   Implementation  begins
------------------------------------------------------------------------
Lower In-Use Emission Performance
 Level:
    Lower Opacity Limits for Heavy-     2018-2024.
     Duty Vehicles.
    Amended Warranty Requirements for   2022.
     Heavy-Duty Vehicles.
    Heavy-Duty Vehicle Inspection and   2022.
     Maintenance Program.
Low-NOX Engine Standard...............  2023.
Innovative Clean Transit..............  2020.
Advanced Clean Local Trucks (Last Mile  2020.
 Delivery).
Zero-Emission Airport Shuttle Buses...  2023.
Zero-Emission Off-Road Forklift         2023.
 Regulation Phase 1.
Zero-Emission Airport Ground Support    2023.
 Equipment.
Small Off-Road Engines................  2022.
Transport Refrigeration Units Used for  2020.
 Cold Storage.
Low-Emission Diesel Fuel Requirement..  2023.
Accelerated Turnover of Trucks and      Ongoing.
 Buses.
Accelerated Turnover of Agricultural    Ongoing.
 Equipment.
Accelerated Turnover of Off-Road        Ongoing.
 Equipment.
------------------------------------------------------------------------

           District measures                 Implementation  begins
------------------------------------------------------------------------
Rule 4311 (``Flares'')................  2023.
Rule 4306 (``Boilers, Steam             2023.
 Generators, and Process Heaters--
 Phase 3''), Rule 4320 (``Advanced
 Emission Reduction Options for
 Boilers, Steam Generators, and
 Process Heaters Greater than 5.0
 MMBtu/hr'').
Rule 4702 (``Internal Combustion        2024.
 Engines'').
Rule 4354 (``Glass Melting Furnaces'')  2023.
Rule 4352 (``Solid Fuel-Fired Boilers,  2023.
 Steam Generators and Process
 Heaters'').
Rule 4550 (``Conservation Management    2024.
 Practices'').
Rule 4692 (``Commercial                 2024.
 Charbroiling'') (Hot-spot Strategy).
Rule 4901 (``Wood Burning Fireplaces    2019.
 and Wood Burning Heaters'') (Hot-spot
 Strategy).
Replacement of Internal Combustion      Ongoing.
 Engines used at Agricultural
 Operations.
Installation of Commercial Under-fired  Ongoing.
 Charbroiling Controls (Hot-spot
 Strategy).
Replacement of Residential Wood         Ongoing.
 Burning Devices (Valley-wide and Hot-
 spot Strategy).
------------------------------------------------------------------------
Source: 2018 PM2.5 Plan, Table 4-4, Table 4-5, Table 4-8 and Appendix H,
  Table H-2.

    Section H.1.3 of Appendix H of the Plan provides the State's and
District's justifications for the stepwise approach to meeting the RFP
requirement and the related implementation schedules for new or revised
control measures. These justifications include the time needed to
engage in the rulemaking process, including time for state and local
public processes; the need to provide time for industry to comply with
new regulatory requirements; the need to resolve feasibility issues for
emerging technologies; and, for CARB mobile source measures, the need
for affected industries to prepare technologies and infrastructure for
market-scale adoption.
    For example, Appendix H of the 2018 PM2.5 Plan states
that ``time after rule adoption will be necessary for unit
manufacturers and vendors to make available compliant equipment, and
for facility operators to source, purchase, and install new units or
compliant retrofit equipment. Dependent on the source category,
construction of controls will include engineering, site preparation and
infrastructure upgrades, unit installation, and operator training on
proper operation.'' \426\
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    \426\ 2018 PM2.5 Plan, App. H, H-7.
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    We present below some of the implementation challenges that the
State and District have identified as part of their justification for
meeting the RFP requirement by the stepwise approach in the Plan.
    The new NOX control measures that CARB and the District
anticipate implementing toward the end of the attainment period can be
found in Table 4-4, Table 4-5, and Table 4-8 of the 2018
PM2.5 Plan. Appendix H of the 2018 PM2.5 Plan
provides the following explanation for the need to implement the listed
measures in a stepwise manner:
    ``The objective of many of CARB's new measures is to introduce or
advance innovative technologies in early stages of development or
market penetration. In the case of technology-forcing regulations, . .
. time is needed by the affected industry to ready the technologies,
including infrastructure, for market-scale adoption, and would have
been discussed previously by CARB and stakeholders during the measure
development phase. The time required to facilitate new and innovative
technologies is a principle driver of the timeline for control measure
implementation CARB laid out in Table 4-8.'' \427\
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    \427\ 2018 PM2.5 Plan, App. H, H-8.
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    CARB provided more specific information regarding two of these
measures on pages H-9 and H-10 of Appendix H. For instance, the
development of the Heavy-Duty Vehicle Inspection and Maintenance
Program was affirmed by California legislative action in 2019, and CARB
is now working on program design and infrastructure to implement new
legislative direction.\428\ For the Low-NOX Engine Standard,
the implementation timeline has been influenced by a multi-year
research program to assess the feasibility of this standard.
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    \428\ California Senate Bill 210, signed September 20, 2019.
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    The new direct PM2.5 measures that CARB and the District
anticipate implementing toward the end of the attainment period can be
found in Table 4-4, Table 4-5, and Table 4-8 of the 2018
PM2.5 Plan. CARB's additional measures are expected to
achieve 0.9 tpd of direct PM2.5 emission reductions \429\
and the District's

additional measures, including revised rules for commercial
charbroiling and conservation management practices (CMPs) for
agricultural operations, are expected to achieve 1.3 tpd of direct
PM2.5 emission reductions in 2024.\430\ New or revised
District measures are thus expected to achieve a significant portion of
the State's and District's 2.2 tpd direct PM2.5 emission
reduction commitment for the 2024 attainment year.
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    \429\ 2018 PM2.5 Plan, Table 4-9.
    \430\ Id. at Table 4-3.
---------------------------------------------------------------------------

    For example, the 2018 PM2.5 Plan shows that
approximately one fourth of the direct PM2.5 emission
reductions that the State and District have committed to achieve by
2024 (0.53 of 2.2 tpd) are expected to result from a planned revision
to the District's commercial charbroiling rule (Rule 4692) that would
contain control requirements for under-fired charbroilers (UFCs).\431\
The District anticipates proposing this revised rule to the SJVUAPCD
Governing Board in 2020 and implementing it beginning in 2024.\432\
According to information provided in Appendix C of the 2018
PM2.5 Plan, the costs associated with retrofitting control
technology onto equipment at existing restaurants and maintaining such
equipment can be prohibitively expensive, especially for smaller
restaurants.\433\ Because of ongoing uncertainties about the
technological and economic feasibility of controls for UFCs, the
District has adopted a set of registration and reporting provisions in
a revised version of Rule 4692 that required owners and operators of
commercial cooking operations with UFCs to register each unit and to
submit, by January 1, 2019, a one-time informational report providing
information about the UFC and its operations. CARB submitted this
revised rule to the EPA on November 16, 2018.
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    \431\ Id. at 4-19, 4-2 and Table 4-3.
    \432\ Id. at Table 4-4.
    \433\ Id. at C-209 to C-210.
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    The 2018 PM2.5 Plan also shows that a portion of the
necessary direct PM2.5 emission reductions in 2024 (0.32 of
2.2 tpd) is expected to result from a revised version of the District's
CMP rule (Rule 4550), which is designed to reduce particulate emissions
from agricultural operations.\434\ The District anticipates proposing
this revised rule to the SJVUAPCD Governing Board in 2022 and
implementing it beginning in 2024.\435\ As explained in Appendix C of
the 2018 PM2.5 Plan, an important step in developing
effective PM2.5 controls for dust from agricultural
operations is to develop an understanding of the effectiveness of CMPs
on controlling PM2.5 emissions in the Valley.'' \436\
Towards this end, the District intends to work with stakeholders and
researchers to evaluate the feasibility and effectiveness of additional
control measures to reduce PM2.5 emissions, including:
Tilling and other land preparation activities; selection of
conservation tillage as a CMP for croplands; and CMPs on fallow lands
that are tilled or otherwise worked with implements of husbandry (e.g.,
a farm tractor drawing a trailer with crops) to reduce windblown PM
emissions from disturbed fallowed acreage.\437\
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    \434\ Id. at Table 4-3.
    \435\ Id. at Table 4-4.
    \436\ The District is holding a series of workshops from January
to March 2020 with the stated goal of ``assisting growers and dairy
families in understanding and complying with District Rule 4550.''
SJVUAPCD, ``Notice of Public Hearing for Adoption of Proposed 2018
PM2.5 Plan for the 1997, 2006, and 2012 Standards,''
available at https://www.valleyair.org/Workshops/postings/2020/2020_CMP/notice.pdf.
    \437\ Id. at C-203.
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b. Quantitative Milestones
    Appendix H of the 2018 PM2.5 Plan identifies December 31
milestone dates for the 2017, 2020, and 2023 milestone years and for
the 2026 post-attainment milestone year.\438\ Appendix H also
identifies target emissions levels to meet the RFP requirement for
direct PM2.5 and NOX emissions for each of these
milestone years,\439\ as shown in Table 10, above, and control measures
that the State or District plan to implement by each of these years, in
accordance with the control strategy in the Plan.\440\
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    \438\ 2018 PM2.5 Plan, App. H, Table H-12.
    \439\ Id. at Table H-5.
    \440\ Id. at H-22 to H-23 (for State milestones) and H-19 to H-
20 (for District milestones).
---------------------------------------------------------------------------

    The Plan includes quantitative milestones for mobile, stationary,
and area sources. For mobile sources, the State has developed
quantitative milestones that provide for evaluation of RFP based on the
implementation of specific control measures by the relevant three-year
milestones. For the first three quantitative milestones, the Plan
provides for evaluating RFP with implementation of regulatory measures;
for the final post attainment date quantitative milestone in 2026, the
Plan provides for evaluating RFP with implementation of incentive
measures.\441\ For the 2017, 2020, and 2023 milestone years, the
quantitative milestones include implementation of the Truck and Bus
Regulation, which requires particulate filters and cleaner engines on
existing trucks and buses, in the years preceding each milestone year
(i.e., between 2012-2017, 2017-2020, and 2020-2023, respectively). Each
of these milestone years also includes action on or implementation of
certain State measures for light-duty vehicles and non-road vehicles as
follows:
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    \441\ Id. at H-22 to H-23.
---------------------------------------------------------------------------

     2017--Truck and Bus Regulation, ACC Program, and Off-Road
Regulation;
     2020--Truck and Bus Regulation, ACC 2: Reduced ZEV Brake
and Tire Wear, and Heavy-Duty Vehicle Inspection and Maintenance
Program; and
     2023--Truck and Bus Regulation and the California Low-
NOX Engine Standard for new on-road heavy-duty engines in
medium- and heavy-duty trucks bought in California.
    For 2026, the Plan's quantitative milestone includes an update on
the State's implementation of two incentive programs, specifically,
identification of the number of trucks and buses turned over to low-
NOX or cleaner engines due to the State's Accelerated
Turnover of Trucks and Buses Measure, and identification of the number
of pieces of agricultural equipment replaced with Tier 4 engines due to
the State's Accelerated Turnover of Agricultural Equipment
Measure.\442\
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    \442\ 2018 PM2.5 Plan, App. H, H-22.
---------------------------------------------------------------------------

    For stationary and area sources, the District has developed
quantitative milestones that similarly include updates on a combination
of regulatory measures and incentive measures. For 2017, the District's
quantitative milestones are to report on its implementation of six
District measures: 2014 amendments to Rule 4901 (``Wood Burning
Fireplaces and Wood Burning Heaters'') and certain incentive programs
for direct PM2.5, Rule 4308 (``Boilers, Steam Generators,
and Process Heaters (0.075 to <2 MMBtu)''), 2011 amendments to Rule
4354 (``Glass Melting Furnaces''), 2013 amendments to Rule 4702
(``Internal Combustion Engines''), Rule 4902 (``Residential Water
Heaters''), and Rule 4905 (``Natural Gas-fired, Fan-type, Residential
Central Furnaces'').\443\
---------------------------------------------------------------------------

    \443\ Id. at H-19.
---------------------------------------------------------------------------

    For the 2020, 2023, and 2026 milestone years, the District's
quantitative milestones are to report on the status of measures
proposed and/or adopted during the preceding three years according to
the schedule in the Plan.\444\ Consistent with the State and District's
control strategy in Chapter 4 of the 2018 PM2.5 Plan, the
District's quantitative milestones include updates on the status of the
District's residential wood burning strategy (both the 2019 amendments
to Rule 4901 and incentive

projects for residential wood burning devices), the District's
incentive-based strategy for commercial under-fired charbroilers, and
the regulatory measures scheduled for SJVUAPCD Board consideration
during the three years preceding the following milestone years:
---------------------------------------------------------------------------

    \444\ Id. at H-19 to H-20.
---------------------------------------------------------------------------

     2020--Rule 4311 (``Flares), Rules 4306/4320 (large
boilers, steam generators, and process heaters), Rule 4702 (``Internal
Combustion Engines''), and Rule 4692 (``Commercial Under-fired
Charbroilers''); and
     2023--Rules 4354 (``Glass Melting Furnaces''), 4352
(``Solid Fuel-Fired Boilers, Steam Generators and Process Heaters''),
and Rule 4550 (``Conservation Management Practices'').\445\
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    \445\ 2018 PM2.5 Plan, Ch. 4, Tables 4-4 and 4-5.
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