[Federal Register Volume 88, Number 175 (Tuesday, September 12, 2023)]
[Notices]
[Pages 62567-62571]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-19116]
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ENVIRONMENTAL PROTECTION AGENCY
[FRL-11012-01-OAR]
Official Release of the MOVES4 Motor Vehicle Emissions Model for
SIPs and Transportation Conformity
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice of availability.
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SUMMARY: The Environmental Protection Agency (EPA) is announcing the
availability of the latest MOtor Vehicle Emission Simulator model major
release (MOVES4) for official purposes outside of California. MOVES4 is
the latest version of EPA's state-of-the science modeling tool for
estimating emissions from cars, trucks, buses, and motorcycles based on
the latest data and regulations. MOVES4 is available for use in state
implementation plans (SIPs) and transportation conformity analyses
outside of California. This notice starts a two-year grace period
before MOVES4 will need to be used as the latest EPA emissions model
for transportation conformity determinations outside of California,
both in new regional emissions analyses and in new hot-spot analyses.
DATES: EPA's announcement of the MOVES4 emissions model for SIPs and
transportation conformity analyses in states other than California is
effective September 12, 2023. This announcement starts a two-year
transportation conformity grace period that ends on September 12, 2025.
After this date, MOVES4 will need to be used as the latest EPA
emissions model for new transportation conformity analyses outside of
California in both regional emissions analyses and in hot-spot
analysis.
FOR FURTHER INFORMATION CONTACT: For technical model questions
regarding the official release or use of MOVES4, please email EPA at
[email protected]. For questions about SIPs, contact Rudy Kapichak at
[email protected]. For transportation conformity questions,
contact Aaron Letterly at [email protected].
SUPPLEMENTARY INFORMATION: The contents of this notice are as follows:
I. General Information
II. What is MOVES4?
III. SIPs and MOVES4
IV. Transportation Conformity and MOVES4
I. General Information
A. Does this action apply to me?
Entities potentially impacted by the approval of MOVES4 are those
that adopt, approve, or fund transportation plans, transportation
improvement programs (TIPs), or projects as defined in 40 CFR 93.101
under title 23 U.S.C. or title 49 U.S.C. chapter 53 and those that
develop and submit SIPs to EPA. Regulated categories and entities
affected by today's action include:
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Category Examples of regulated entities
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Local government............. Local air quality and transportation
agencies, including metropolitan
planning organizations (MPOs).
State government............. State air quality and transportation
agencies.
[[Page 62568]]
Federal government........... Department of Transportation (Federal
Highway Administration (FHWA) and
Federal Transit Administration (FTA)).
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This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely to be affected by the
release of MOVES. Other entities not listed in the table could also be
affected. To determine whether your organization is affected by this
action, you should carefully examine the transportation conformity
applicability requirements in 40 CFR 93.102. If you have questions
regarding the applicability of this action to a particular entity,
consult the persons listed in the preceding FOR FURTHER INFORMATION
CONTACT section.
B. How can I get copies of MOVES4 and other related information?
The official version of the MOVES4 model and supporting
documentation are available on EPA's MOVES website: www.epa.gov/moves.
Individuals who want to receive EPA announcements related to the MOVES4
model can subscribe to the EPA-MOBILENEWS email listserv, which can be
done at EPA's website at: www.epa.gov/moves/forms/epa-mobilenews-listserv.
Available guidance on how to apply MOVES4 for SIPs and
transportation conformity purposes can be found on EPA's transportation
conformity website, www.epa.gov/state-and-local-transportation/policy-and-technical-guidance-state-and-local-transportation,\1\ including
``MOVES4 Policy Guidance: Use of MOVES for State Implementation Plan
Development, Transportation Conformity, General Conformity, and Other
Purposes.'' (420-B-23-009, August 2023).
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\1\ Interested parties can find these documents under the
``Emission Models and Conformity'' and ``Project-Level Conformity''
topics on this website.
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EPA will continue to update these websites as other MOVES support
materials and guidance are developed or updated.
II. What is MOVES4?
MOVES4 is EPA's latest motor vehicle emissions model for state and
local agencies to estimate volatile organic compounds (VOCs), nitrogen
oxides (NOX), particulate matter (PM2.5 and
PM10), carbon monoxide (CO), and other pollutants and
precursors from cars, trucks, buses, and motorcycles for SIP purposes
and conformity determinations outside of California.\2\ The model is
based on analyses of millions of emission test results and considerable
advances in the Agency's understanding of vehicle emissions. MOVES4 is
a major revision to the MOVES series of models. This model is the
fourth major MOVES release--the first three were MOVES2010, MOVES2014,
and MOVES3.\3\
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\2\ MOVES can also model emissions in the District of Columbia,
Puerto Rico, and the U.S. Virgin Islands. Nonattainment and
maintenance areas located in California use the latest approved
version of the Emission FACtor (EMFAC) model.
\3\ For more information, see EPA's MOVES Versions in Limited
Current Use website.
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MOVES4 includes new regulations, features, and significant new
data, as detailed in the MOVES4 technical reports. Notably, MOVES4
incorporates:
The emission impacts of the EPA heavy-duty low
NOX rule for model years 2027 and later \4\ and the light-
duty greenhouse gas rule for model years 2023 and later.\5\
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\4\ 88 FR 4296, January 24, 2023.
\5\ 86 FR, December 30, 2021.
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The ability to model heavy-duty battery-electric and fuel-
cell vehicles, as well as CNG long-haul combination trucks.
Improved modeling of light-duty electric vehicles.
New tools to make the model easier to use and updates for
compatibility with newer software.
Updated data and forecasts on vehicle populations
(including electric vehicle fractions), travel activity, and emission
rates, as well as updated fuel supply information at the county level.
The latest data on ammonia emission rates for light-duty
and heavy-duty vehicles.
A number of limited-impact updates to specific emissions
rates and adjustments.
Like its predecessors, MOVES4 includes the capability to estimate
vehicle exhaust and evaporative emissions as well as brake wear and
tire wear emissions for criteria pollutants and precursors. However,
like previous versions, MOVES4 does not include the capability to
estimate emissions of re-entrained road dust. To estimate emissions
from re-entrained road dust, practitioners should continue to use the
latest approved methodologies.\6\
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\6\ See EPA's notice of availability, ``Official Release of the
January 2011 AP-42 Method for Estimating Re-Entrained Road Dust from
Paved Roads,'' published in the Federal Register on February 4, 2011
(76 FR 6328).
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The structure of MOVES4 is fundamentally the same as MOVES3,
although there are new format options for some inputs, and the model
run time may differ depending on the type of run and user inputs and
computer configuration. As for emissions, EPA performed a comparison of
MOVES4 to MOVES3 using default information in MOVES4 at the national
level, and for three sample urban counties with different local travel
patterns and ambient conditions. In general, compared to MOVES3, MOVES4
will produce notable decreases in NOX for future years due
to the emissions reductions of new regulations and small decreases in
most other pollutants. However, ammonia emissions increase
significantly because real-world emission measurements show ammonia
emissions from both gasoline and diesel vehicles are much higher than
MOVES3 predicted. Similarly, nitrous oxide (N2O) emissions
have increased due to new data for heavy-duty diesel vehicles. Note
that results will vary based on the pollutant selected and that area's
local inputs.
III. SIPs and MOVES4
EPA has articulated its policy regarding the use of MOVES4 in SIP
development in its ``MOVES4 Policy Guidance: Use of MOVES for State
Implementation Plan Development, Transportation Conformity, General
Conformity, and Other Purposes'' (EPA-420-B-23-009, August 2023).
Today's notice highlights certain aspects of the guidance, but state
and local governments should refer to the guidance for more detailed
information on how and when to use MOVES4 in reasonable further
progress SIPs, attainment demonstrations, maintenance plans, inventory
updates, and other SIP submissions.
MOVES4 should be used in ozone, CO, PM, and nitrogen dioxide
(NO2) SIP development as expeditiously as possible, as there
is no grace period for the use of MOVES4 in SIPs. The Clean Air Act
requires that SIP inventories and control measures be based on the most
current information and applicable models that are available when a SIP
is developed.\7\ However, EPA also
[[Page 62569]]
recognizes the time and level of effort that certain states may have
already undertaken in SIP development using a version of MOVES3. States
should consult with their EPA Regional Office if they have questions
about how MOVES4 affects SIPs under development in specific
nonattainment or maintenance areas. Early consultation can facilitate
EPA's adequacy finding for SIP motor vehicle emissions budgets for
transportation conformity purposes or EPA's SIP approval.
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\7\ See Clean Air Act section 172(c)(3). Also see the discussion
of emissions inventory requirements in the ``Fine Particulate Matter
National Ambient Air Quality Standards: State Implementation Plan
Requirements'' rule (81 FR 58029, August 24, 2016) and in the
``Implementation of the 2015 National Ambient Air Quality Standards
for Ozone: Nonattainment Area State Implementation Plan
Requirements'' rule (83 FR 63022, December 6, 2018).
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States should use the latest version of MOVES that is available at
the time that a SIP is developed. All states other than California
should use MOVES4 for SIPs that will be submitted in the future so that
they are based on the most accurate estimates of emissions possible.
However, state and local agencies that have already completed
significant work on a SIP with a version of MOVES3 (e.g., attainment
modeling has already been completed with MOVES3) may continue to rely
on this earlier version of MOVES. It would be unreasonable to require
the states to revise these SIPs with MOVES4 since significant work has
already occurred based on the latest information available at the time
the SIP was developed, and EPA intends to act on these SIPs in a timely
manner.
The Clean Air Act does not require states that have already
submitted SIPs or will submit SIPs shortly after the release of a new
model to revise these SIPs simply because a new motor vehicle emissions
model is now available.\8\ States can choose to use MOVES4 in these
SIPs, for example, if it is determined that it is appropriate to update
motor vehicle emissions budgets (``budgets'') with the model for future
conformity determinations. However, as stated above, states should use
MOVES4 where SIP development is in its initial stages or has not
progressed far enough along that switching from a previous model
version would create a significant adverse impact on state resources.
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\8\ Sierra Club v. EPA, 356 F.3d. 296, 308 (D.C. Cir. 2004)
(``To require states to revise completed plans every time a new
model is announced would lead to significant costs and potentially
endless delays in the approval processes.'')
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Incorporating MOVES4 into the SIP now could assist areas in
mitigating possible transportation conformity difficulties in the
future after the MOVES4 conformity grace period ends. New regional
emissions analyses using EPA's emissions model that are started after
the grace period is over must be based on MOVES4 (40 CFR 93.111), so
having MOVES4-based SIP budgets in place at that time could provide
more consistency with transportation conformity determinations.
IV. Transportation Conformity and MOVES4
In today's notice, EPA is announcing the availability of MOVES4 for
use in transportation conformity analyses outside of California. EPA is
also establishing a two-year grace period before MOVES4 will need to be
used in regional emissions analysis for transportation conformity
determinations and in hot-spot analyses for project-level
transportation conformity determinations which use EPA's emissions
model. The MOVES4 grace period for regional emissions and hot-spot
analyses applies to the use of MOVES4 and any future minor revisions
that occur during the grace period.
Transportation conformity is a Clean Air Act requirement to ensure
that federally supported highway and transit activities are consistent
with (``conform to'') the SIP. Conformity to a SIP means that a
transportation activity will not cause or contribute to new air quality
violations; worsen existing violations; or delay timely attainment of
national ambient air quality standards or any interim milestones.
Transportation conformity applies in nonattainment and maintenance
areas for transportation-related pollutants: ozone, CO,
PM2.5, PM10 and NO2. EPA's
transportation conformity regulations (40 CFR parts 51.390 and 93
subpart A) describe how federally funded and approved highway and
transit projects meet these statutory requirements.
The remainder of this section describes how the transportation
conformity grace period was determined and summarizes how it will be
implemented, including those circumstances when the grace period could
be shorter than two years for regional emissions analyses. However, for
complete explanations of how MOVES4 is to be implemented for
transportation conformity, including details about using MOVES4 during
the grace period, refer to ``MOVES4 Policy Guidance: Use of MOVES for
State Implementation Plan Development, Transportation Conformity,
General Conformity, and Other Purposes.'' (EPA-420-B-23-009).
A. Why is EPA establishing a two-year conformity grace period?
Section 176(c)(1) of the Clean Air Act states that ``. . .[t]he
determination of conformity shall be based on the most recent estimates
of emissions, and such estimates shall be determined from the most
recent population, employment, travel, and congestion estimates. . .''.
Additionally, the transportation conformity rule (40 CFR 93.111)
requires conformity analyses to be based on ``the latest emissions
estimation model available,'' and further states that this requirement
is satisfied if the most current version of EPA's motor vehicle
emissions model is used. When EPA announces a new emissions model, such
as MOVES4, we establish a grace period before the model needs to be
used for transportation conformity purposes (40 CFR 93.111(b)). In
consultation with DOT, EPA must consider the degree of change in the
emissions model and the effects of the new model on the transportation
planning process (40 CFR 93.111(b)(2)). The transportation conformity
rule provides that EPA will establish a grace period for new emissions
models of between three and 24 months (40 CFR 93.111(b)(1)).
EPA articulated its intentions for establishing the length of a
conformity grace period in the preamble to the 1993 transportation
conformity rule (November 24, 1993; 58 FR 62211):
``EPA and DOT [the Department of Transportation] will consider
extending the grace period if the effects of the new emissions model
are so significant that previous SIP demonstrations of what emission
levels are consistent with attainment would be substantially affected.
In such cases, States should have an opportunity to revise their SIPs
before MPOs must use the model's new emissions factors.''
In consultation with DOT, EPA considered the degree of change in
MOVES4 and the effects of the new model on the transportation planning
process (40 CFR 93.111(b)(2)). EPA considered the time it will take
state and local transportation and air quality agencies to conduct and
provide technical support for analyses. State and local agencies will
need to become familiar with the MOVES4 emissions model and may need to
convert existing data for use in MOVES4. Since 1993, the fundamental
purpose of section 93.111(b) of the transportation conformity rule has
been to provide a sufficient amount of time for MPOs and other state
and local agencies to learn and employ new emissions models. The
transition to a new emissions model for conformity involves more than
learning to use the new model and preparing input data and model
output. After model start-up is complete, state and local agencies also
need to consider how the model affects regional emissions analysis
results and whether SIP and/or transportation plan/TIP changes are
[[Page 62570]]
necessary to assure future conformity determinations.
The two-year conformity grace period also provides sufficient time
for state and local agencies to learn and apply new technical guidance
and training that reflect MOVES4. EPA is working to update guidance
documents and training materials as quickly as possible. EPA will
notify MOVES4 users when these important materials are available.
Training materials will address different levels of state and local
expertise.
In addition, many agencies will be implementing the transition to
MOVES4 for PM and CO hot-spot analyses for applicable projects in those
nonattainment and maintenance areas, with each analysis potentially
involving multiple state and local agencies. States with CO hot-spot
protocols that were previously approved into the SIP (40 CFR
93.123(a)(1)) that are based on a previous model will need time to
revise them. Additional time is necessary to revise previously approved
CO hot-spot protocols, and the SIP revision process and state
requirements can vary. Finally, EPA considered the general time and
monetary resource constraints in which state and local agencies
currently operate. Upon considerations of all these factors, EPA is
establishing a two-year grace period, which begins today and ends on
September 12, 2025, before MOVES4 needs to be used for new
transportation conformity analyses outside of California.
B. Circumstances When Grace Period Will Be Shorter Than Two Years
The grace period for regional emissions analyses will be shorter
than two years for a given pollutant if an area revises its SIP and
motor vehicle emissions budgets with MOVES4 and such budgets have been
found adequate or approved into the SIP prior to the end of the two-
year grace period. In this case, the new regional emissions analysis
must use MOVES4 if the conformity determination is based on a MOVES4-
based budget (40 CFR 93.111).
Areas that are designated nonattainment or maintenance for multiple
pollutants may rely on both MOVES4 and MOVES3 to determine conformity
for different pollutants during the grace period. For example, if an
area revises a previously submitted (but not approved) MOVES3-based
PM10 SIP with MOVES4 and EPA finds these revised MOVES4
budgets adequate for conformity, such budgets would apply for
conformity on the effective date of the Federal Register notice
announcing EPA's adequacy finding. In this example, if the area is
nonattainment for PM10 and ozone, the MOVES4 grace period
would end for PM10 regional emissions analyses once EPA
found the new MOVES4-based SIP budgets adequate. However, MOVES3 could
continue to be used for ozone-related regional emissions analyses begun
before the end of the MOVES4 grace period.\9\ In addition, the length
of the grace period for hot-spot analyses would not be affected by an
early submission of MOVES4-based budgets. In this example, the two-year
grace period for PM10 hot-spot analyses would continue to
apply even if the grace period is shortened for regional
PM10 conformity analyses. EPA Regional Offices should be
consulted for questions regarding such situations in multi-pollutant
areas.
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\9\ In this example, such an area would use MOVES4 to develop a
regional emissions analysis for PM10 for comparison to
the revised MOVES4-based budgets (e.g., PM10 budgets).
The regional emissions analysis for ozone could be based on MOVES3
for the VOC and NOX budgets in the ozone SIP for the
remainder of the conformity grace period.
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In addition, in most cases, if the state revises previously
approved budgets based on an earlier EPA emissions model, the revised
MOVES4 budgets could not be used for conformity purposes until EPA
approves them, i.e., approves the SIP revision. In general, submitted
SIPs cannot supersede approved budgets until the submitted SIP is
approved. See 40 CFR 93.118(e)(1).
However, 40 CFR 93.118(e)(1) allows an approved budget to be
replaced by an adequate budget if EPA's approval of the initial budgets
specifies that the budgets being approved may be replaced in the future
by new adequate budgets. This flexibility has been used in limited
situations in the past. In such cases, the MOVES4-based budgets would
be used for conformity purposes once they have been found adequate, if
requested by the state in its SIP submission and specified in EPA's SIP
approval. States should consult with their EPA Regional Office to
determine if this flexibility applies to their situation.
C. Use of MOVES4 for Regional Emissions Analyses During the Grace
Period
During the conformity grace period, areas should use interagency
consultation to examine how MOVES4 will impact their future
transportation plan and TIP conformity determinations, including
regional emissions analyses. Isolated rural areas should also consider
how future regional emissions analyses will be affected when the MOVES4
grace period ends. Areas should carefully consider whether the SIP and
budgets should be revised with MOVES4 or if transportation plans and
TIPs should be revised before the end of the conformity grace period,
since doing so may be necessary to ensure conformity in the future.
Finally, the transportation conformity rule provides flexibility
for completing conformity determinations based on regional emissions
analyses that use MOVES3 that are started before the end of the grace
period. Regional emissions analyses that are started during the grace
period can use either MOVES3 or MOVES4. The interagency consultation
process should be used if it is unclear if a MOVES3-based analysis was
begun before the end of the grace period. If there are questions about
which model should be used in a conformity determination, the EPA
Regional Office can be consulted.
When the grace period ends on September 12, 2025, MOVES4 will
become the only EPA motor vehicle emissions model for regional
emissions analyses for transportation conformity in states other than
California. In general, this means that all new transportation plan and
TIP conformity determinations started after the end of the grace period
must be based on MOVES4, even if the SIP is based on MOVES3 or an older
version of the MOVES model.
D. Use of MOVES4 for Project-Level Hot-Spot Analyses During the
Conformity Grace Period
The MOVES4 grace period also applies to the use of MOVES4 for CO,
PM10 and PM2.5 hot-spot analyses. Sections 93.116
and 93.123 of the transportation conformity regulation contain the
requirements for when a hot-spot analysis is required for project-level
conformity determinations.\10\ The transportation conformity rule
provides flexibility for analyses that are started before the end of
the grace period. A conformity determination for a transportation
project may be based on a previous model if the analysis was begun
before or during the grace period, and if the final environmental
document for the project is issued no more than three years after the
issuance of the draft environmental document (40 CFR 93.111(c)).
Interagency consultation should be used if it is unclear if a
[[Page 62571]]
previous analysis was begun before the end of the grace period. For CO,
PM10 and PM2.5 hot-spot analyses that start
during the grace period, project sponsors can choose to use MOVES3 or
MOVES4.
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\10\ In CO nonattainment and maintenance areas, a hot-spot
analysis is required for all non-exempt projects, with quantitative
hot-spot analyses being required for larger, congested intersections
and other projects (40 CFR 93.123(a)(1)). In addition, in
PM2.5 and PM10 nonattainment and maintenance
areas, the transportation conformity regulation requires that a
quantitative hot-spot analysis be completed for certain projects
(see 40 CFR 93.123(b)(1)).
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EPA encourages sponsors to use the consultation process to
determine which option may be most appropriate for a given situation.
Any new CO, PM10 or PM2.5 hot-spot analyses for
conformity purposes begun after the end of the grace period must be
based on MOVES4. EPA has guidance on how to conduct quantitative
PM2.5 and PM10 hot-spot modeling for
transportation conformity purposes, and on how to use MOVES for a CO
hot-spot analysis. Until EPA updates these guidance documents, the
MOVES3-based guidance still generally applies for MOVES4. See EPA's
``Project-level Conformity'' website, www.epa.gov/state-and-local-transportation/project-level-conformity-and-hot-spot-analyses, for the
latest information and guidance documents on how to conduct CO,
PM10 and PM2.5 hot-spot modeling for
transportation conformity purposes.
Any new, quantitative CO, PM10 or PM2.5 hot-
spot analysis for conformity purposes begun after the end of the grace
period using EPA's emissions model must use MOVES4. The interagency
consultation process should be used if it is unclear whether these
conditions are met. For questions about which model should be used in a
project-level conformity determination, consult with your EPA Regional
Office.
E. FHWA's CO Categorical Hot-Spot Finding
FHWA released the most recent CO categorical hot-spot finding for
intersection projects on January 31, 2023, that was based on
MOVES3.\11\ During the MOVES4 grace period, a project sponsor outside
of California may continue to rely on the categorical finding for
applicable projects that are determined through interagency
consultation to be covered by the finding's parameters. However, new CO
hot-spot analyses for conformity purposes begun after the end of the
MOVES4 grace period would not be able to rely on the MOVES3-based
January 2023 CO categorical hot-spot finding.
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\11\ See www.epa.gov/state-and-local-transportation/project-level-conformity-and-hot-spot-analyses#cohotspot.
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F. CO Hot-Spot Protocols That Were Previously Approved Into the SIP
Section 93.123(a)(1) of the transportation conformity regulation
allows areas to develop alternate procedures for determining localized
CO hot-spot analyses, when developed through interagency consultation
and approved by the EPA Regional Administrator. Some states have chosen
in the past to develop such procedures based on previous EPA emissions
models.
During the MOVES4 grace period, areas with previously approved CO
hot-spot protocols based on MOVES3 may continue to rely on these
protocols. Once the MOVES4 two-year grace period ends, new CO hot-spot
analyses for conformity purposes will need to be based on MOVES4.
Previously approved SIP CO hot-spot protocols that are based on
emissions models prior to MOVES3 can no longer be used for
transportation conformity purposes.
Karl Simon,
Director, Transportation and Climate Division, Office of Transportation
and Air Quality.
[FR Doc. 2023-19116 Filed 9-11-23; 8:45 am]
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