As stated above and similar to the SAFE 1 Reconsideration decision,
EPA continues to believe the best way to interpret this provision is to
determine whether California continues to have compelling and
extraordinary conditions giving rise to a need for its own new motor
vehicle emission program.\135\ EPA believes this continues

to be true for section 209(b)(1)(B), which was at issue in the SAFE 1
Reconsideration action.\136\ EPA finds that California has demonstrated
that it needs its program to address compelling and extraordinary
conditions, those arising from criteria pollution and separately, those
arising from greenhouse gases. No comments have provided an analytical
basis for undermining California's need.\137\
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    \135\ To the extent comments contend that EPA's interpretation
of the second waiver prong provides preferential treatment to
California over other States, EPA notes that the review of CARB
waiver requests is limited to the criteria set forth in section 209
and that we need not engage in an Equal Sovereignty constitutional
law analysis. (See SAFE 1 Reconsideration Decision at 14376). In any
case, for the purposes of reviewing the second waiver prong, EPA
incorporates the reasoning from the SAFE 1 Reconsideration Decision
at 14360. As such, EPA evaluates CARB's waiver requests based solely
on the criteria in section 209(b)(1) and does not consider factors
outside of those statutory criteria, including constitutional
claims. EPA continues to note that Congress struck a reasonable
balance in authorizing two standards (EPA's and California's if
certain criteria are met) but that that equal sovereignty principle
simply does not fit in section 209. EPA further addresses the
commenter's concerns relating to the Equal Sovereignty doctrine in
the Other Issues section below. Similarly, to the extent that
commenters contend that EPA's traditional interpretation raises
questions of vast economic and political significance where Congress
must speak clearly, EPA believes that this doctrine is inapplicable.
That doctrine posits that in certain extraordinary cases, Congress
should not be presumed to delegate its own authority over matters of
vast economic and political significance to Federal agencies in the
absence of clear statutory authorization. These concerns have no
logical connection to provisions that preserve state authority in
areas that fall within the police powers of states, such as the
protection of the environment. Further, EPA has consistently
explained that section 209(b)(1) of the Act limits the Agency's
authority to deny California's requests for waivers to the three
criteria contained therein and as such the Agency has consistently
refrained from reviewing California's requests for waivers based on
any other criteria. EPA acknowledges that California adopts its
standards as a matter of law under its state police powers, that the
Agency's task in reviewing waiver requests is limited to evaluating
California's request according to the criteria in section 209(b).
Furthermore, the language of section 209 provides clear statutory
authorization for the waiver framework, and the history of section
209(b) and (e) provide additional evidence that Congress intended
for California to have great deference in designing its own vehicle
program. MEMA I, 627 F.2d at 1111.
    \136\ EPA notes that if Congress had been concerned with only
California's smog problems when it enacted section 209(b) in 1967 it
would have limited California's ability to obtain a waiver to
standards for only hydrocarbons and NOX, which are the
known automotive pollutants that contribute to California's smog
problem. But Congress was aware that California would most likely
decide to regulate other non-smog forming pollutants. ``[T]he total
program for control of automotive emissions is expected to include
[in addition to hydrocarbons and oxides of nitrogen] carbon
monoxide, lead and particulate matter.'' 123 Cong. Rec. 30951
(November 2, 1967) (Remarks of Rep. Herlong). Further, Congress
intended that California would serve as a pioneer and a laboratory
for the nation in setting new motor vehicle emission standards and
developing control technology, which extends to ZEVs, BEVs, FCVs and
PHEVs. ``The waiver of preemption is for California's ``unique
problems and pioneering efforts.'' S. Rep. No. 403, 90th Cong., 1st
Sess. 33 (1967); 113 Cong. Rec. 30950, 32478 (``[T]he State will act
as a testing agent for various types of controls and the country as
a whole will be the beneficiary of this research.'') (Statement of
Sen. Murphy). Thus, for example, in the 1990 Amendments Congress
mandated California's LEV program, which includes the ZEV program,
in its State Implementation Plan provision regarding fleet programs
required for certain non-attainment areas relating to issuing
credits for innovative and cleaner vehicles. Specifically,
``standards established by the Administrator under this paragraph .
. . shall conform as closely as possible to standards which are
established for the State of California for ULEV and ZEV vehicles in
the same class. Section 246(f)(4). (``[W]hen it amended the Act in
1990, [Congress recognized] California's LEV program, including the
ZEV mandate. See e.g., Act sections 241(4), 243(f), 246(f)(4).''
MVMA, 17 F.3d at 536.) See also 87 FR at 14360.
    \137\ EPA notes that CARB ACT Regulation is only regulating
emissions from new motor vehicles and that such standards are the
types preempted under section 209(a). Section 209(b) requires EPA to
waive such standards unless one or more of the specified criteria
are found. CARB's ACT Regulation is focused on emissions of air
pollutants from this vehicle source and to EPA's knowledge is not
designed to address a broader set of transportation and energy
issues nor is the scope of the waiver criteria in section 209
designed for such a broad and searching review.
---------------------------------------------------------------------------

    Although nothing in the statutory text limits California's program
or the associated waivers to a certain category of air pollution
problems, EPA notes that each of the regulations contained in the two
waiver requests from CARB is clearly designed to address emissions of
criteria pollutants and will have that effect, regardless of whether
some also reduce greenhouse gases. As such, these standards are no
different from all prior standards addressing criteria emissions that
EPA has found to satisfy the section 209(b)(1)(B) inquiry. In any case,
there is no statutory basis to suggest that GHG emissions should be
treated any differently.
    Further, it is inappropriate for EPA to second-guess CARB's policy
choices and objectives in adopting its heavy-duty vehicle and engine
standards designed to achieve long term emission benefits for both
criteria emissions and greenhouse gas emissions. EPA's longstanding
practice, based on the statutory text, legislative history, and
precedent, calls for deference to California in its approach to
addressing the interconnected nature of air pollution within the state.
Critically, EPA is not to engage in ``probing substantive review'' of
waiver requests,\138\ but rather to ``afford California the broadest
possible discretion in selecting the best means to protect the health
of its citizens and the public welfare.'' \139\
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    \138\ Ford Motor, 606 F.2d 1293, 1300 (D.C. Cir. 1979).
    \139\ MEMA II, 142 F.3d 449, 453 (D.C. Cir. 1998).
---------------------------------------------------------------------------

    As noted above, the term compelling and extraordinary conditions
``does not refer to the levels of pollution directly.'' \140\
California continues to experience compelling and extraordinary
conditions that cause it to need a separate motor vehicle emissions
program. These include geographical and climatic conditions (like
thermal inversions) that, when combined with large numbers and high
concentrations of automobiles, create serious air pollution
problems.\141\ For example, as stated in CARB's waiver request and
additional written comment, California and particularly the South Coast
and San Joaquin Valley Air Basins continue to experience some of the
worst air quality in the nation and continue to be in nonattainment
with several NAAQS.\142\ In the context of these serious and long-
lasting pollution challenges, California has demonstrated that every
reduction in ozone precursor and particulate emissions is particularly
critical.
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    \140\ 49 FR 18887, 18890 (May 3, 1984).
    \141\ In response to commenters that believe that the
traditional interpretation is simply a ``rubber-stamp[ ]'' because
EPA has already once decided that California ``needs'' its own motor
vehicle program, EPA notes that although California has yet to
resolve its pollution problems, that does not mean it will never do
so or that Congress could not aim for that goal. See 87 FR at 14336
n.22. So long as those problems persist, however, EPA's affirmance
of California's need for a separate vehicle program allows
California to continue to serve as a ``laboratory'' for resolving
its own pollution problems and those of the entire nation. See MEMA
I, 627 F.2d at 1109-11.
    \142\ See, e.g., CARB Supplemental Comments at 5-6, n.36; CARB
Initial ACT/ZEAS/ZEP Comments at 11, 14-15; SJVUAPCD at 2 (``Despite
achieving significant emissions reductions through decades of
implementing the most stringent stationary and mobile regulatory
control program in the nation, significant additional reductions in
nitrogen oxide (NOX) emissions are needed to attain the
latest health-based National Ambient Air Quality Standards (NAAQS)
for ozone and PM2.5.''); State of California et al at 12-
13 (``Sixteen of the 8-hour ozone nonattainment areas are located in
California and the only two extreme nonattainment areas in the
nation are located in the South Coast Air Basin and San Joaquin
Valley of California. Indeed, for the South Coast Air Basin to meet
the federal ozone standards, overall NOX emissions need
to be reduced by 70 percent from today's levels by 2023, and
approximately 80 percent by 2031.''); Environmental and Public
Health Organizations at 32 (``California continues to experience
some of the worst air quality in the nation. The South Coast and San
Joaquin Valley Air Basins are in non-attainment of the national
ambient air quality standards for PM2.5 and ozone. The
South Coast has never met any of the federal ozone standards
established pursuant to the Clean Air Act . . . [H]eavy-duty
vehicles represent the largest source of NOX emissions
reductions needed to attain the 2015 8-hour ozone National Ambient
Air Quality Standards (NAAQS), and California's air quality
regulations, like those at issue here, are central to the state's
attainment strategy for the South Coast Air Basin.'').
---------------------------------------------------------------------------

    In addition, EPA did not receive any adverse comments suggesting
that California no longer needs a separate motor vehicle emissions
program to address the various conditions that lead to serious and
unique air pollution problems in California. EPA did receive comment
that contends that California does not have a need for its standards as
only two areas in the State (the San Joaquin Valley and the South
Coast)

have serious air quality issues. EPA believes this commenter misses the
mark for several reasons. The commenter provided no legal rationale for
limiting the ``compelling and extraordinary conditions'' to those
conditions experienced by all of California. In addition, California is
responsible, in part, for developing State Implementation Plan (SIP)
measures to address nonattainment and maintenance and EPA sees no basis
to deny a waiver for regulations designed at the state level and that
address emission sources that move around the state. Nor has the
commenter provided sufficient data or analysis to demonstrate that
other areas of California do not need the motor vehicle standards
program to address compelling and extraordinary conditions. Based on
the record, EPA is unable to identify any change in circumstances or
any evidence to undermine EPA's prior findings that California needs
its motor vehicle emissions program to address compelling and
extraordinary conditions. Therefore, using the traditional approach of
reviewing the need for a separate California program to meet compelling
and extraordinary conditions, EPA cannot deny any of the waiver
requests.
    Further, EPA does not believe, to the extent that it is appropriate
to examine the need for CARB's individual heavy-duty vehicle and engine
standards to meet compelling and extraordinary conditions, that the
opponents of the waiver requests have met their burden of proof that
California does not need these standards. The record demonstrates that
each regulation in the two waiver requests is designed to produce
reductions in criteria emissions that continue to be a serious air
quality concern in California, which is a result of its compelling and
extraordinary conditions. While EPA believes that CARB has demonstrated
the criteria emission reductions associated with its ACT, ZEAS, and ZEP
Certification Regulations and therefore a need for such standards, EPA
also believes that, to the extent such standards are designed to also
address climate change conditions in California, such standards are
needed to meet compelling and extraordinary conditions.\143\ EPA notes
that the record contains evidence that global warming continues to pose
an extraordinary threat to the economic well-being, public health,
natural resources and environment in California. These adverse impacts
include exacerbation of local air quality problems, severe wildfires,
extreme drought, acidification threats to marine ecosystems as carbon
dioxide is absorbed by the ocean along California's coastline, and a
host of other impacts.\144\ EPA believes the same conditions and
impacts assessed in the SAFE 1 Reconsideration Decision apply to this
waiver decision and incorporates that analysis here.\145\
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    \143\ 87 FR 14332, 14365-66 (March 14, 2022).
    \144\ California Supplemental ACT Comments at 16-17, California
also noted that the ACT Regulation will ensure the development and
commercialization of technology required to achieve further emission
reductions to address climate changes and to attain national ambient
air quality standards (NAAQS) in California.
    \145\ 87 FR 14332, 14334, 14352-55, 14358-62.
---------------------------------------------------------------------------

    Regarding comments received that the 2018 HD Warranty Amendments
are not needed because EPA's HD 2027 rule and CARB's Heavy-Duty
Inspection & Maintenance Program are or will be more effective, EPA
notes that California is entitled to substantial deference in its
policy choices regarding the best path to address its air pollution
problems, including the choice to adopt or retain emission standards
that overlap with previous California standards and EPA's
standards.\146\ In the context of these arguments about effectiveness,
it is important to note that under the statute, California's standards
in the aggregate must be as protective as EPA's standards--there is no
requirement that they be more protective. This reinforces the deference
owed to California in its determination of whether it needs a
particular configuration of standards as its program to address
compelling and extraordinary conditions. In response to comments
received that the specific regulations are not necessary (as a factual
matter) because they may slow fleet turnover, EPA finds that these
commenters have not met their burden of proof to demonstrate that such
a result in fleet turnover will occur and that if it did occur, it
would cause an increase in emissions. Commenters have also failed to
demonstrate that California does not continue to need every reduction
in criteria pollutant emissions it can obtain.\147\ As EPA continues to
believe California has compelling and extraordinary conditions, it is
appropriate for EPA to continue giving substantial deference to
California's policy choices on how it chooses to protect public health
and welfare and achieve its air quality objectives.
---------------------------------------------------------------------------

    \146\ See, e.g., 78 FR at 2129 (``The Commenter . . . relies on
the existence of the federal GHG standards and the `deemed to
comply' language to claim that there is no need for CARB's GHG
standards . . . EPA believes that the commenter does not
appropriately appreciate the role that Congress envisioned
California to play as an innovative laboratory that may set
standards that EPA may ultimately harmonize with or that California
or EPA may otherwise accept compliance with the others emission
program as compliance with their own.''). In addition, given that
there are a variety of regulatory measures and levels of stringency
that California may choose to address the durability of emission
controls on vehicles and engines while in use, and the lack of
evidence in the record that an inspection and maintenance program is
more protective than a warranty regulation (or that both may be
implemented at some point), EPA finds that opponents of the waiver
have not met their burden of proof with evidence to support their
policy preference on an inspection and maintenance program.
    \147\ CARB Supplemental Comments at 5-6 (``But AFPM provides no
evidence that ACT will slow fleet turnover at all, let alone to the
degree necessary to increase pollution. And none of these comments
refutes CARB's conclusion that zero-emission vehicles placed into
well-suited applications will be less expensive, over their
lifetimes, than conventional ones, or explains why the requirement
to sell a certain percentage of vehicles that will save owners or
operators money would slow turnover to the (unspecified) extent
required to increase emissions. Moreover, the recently passed
Inflation Reduction Act includes numerous financial incentives that
will decrease the cost of zero-emission heavy-duty vehicles, further
undercutting the claim that the high costs of those vehicles will
slow fleet turnover.'').
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5. Section 209(b)(1)(B) Conclusion
    As previously explained, EPA believes that the traditional
interpretation of the section 209(b)(1)(B) criterion is the best
reading of the statute.\148\ The traditional approach is for EPA to
evaluate California's need for a separate motor vehicle emission
program to meet compelling and extraordinary conditions. The issue of
whether any particular standard is needed is not the inquiry directed
under section 209(b)(1)(B). Applying the traditional approach of
assessing California's need for a separate motor vehicle emissions
program to address compelling and extraordinary conditions, with the
reasoning noted above and with due deference to California, EPA cannot
deny the respective waiver requests. CARB has repeatedly demonstrated
the need for its motor vehicle program to address compelling and
extraordinary conditions in California and opponents of the waiver
requests have not demonstrated that California does not need its state
standards to meet compelling and extraordinary conditions. Therefore, I
determine that I cannot deny either of the waiver requests under
section 209(b)(1)(B).
---------------------------------------------------------------------------

    \148\ 87 FR 14332, 14334, 14352-55, 14358-62 (March 14, 2022).
---------------------------------------------------------------------------

    In addition, although EPA does not believe an interpretation that
requires a demonstrated need for a specific standard is appropriate,
EPA's review of the complete record indicates that opponents of the
waiver requests have not met the burden of proof necessary to
demonstrate that California does not

need its ACT Regulation, ZEAS Regulation, ZEP Certification Regulation,
and the 2018 HD Warranty Amendments when assessed individually.

D. Third Waiver Criterion: Are California's Regulations Consistent With
Section 202(a) of the Clean Air Act?

    Under section 209(b)(1)(C), EPA must grant California's waiver
request unless the Agency finds that California's standards and
accompanying enforcement procedures are not consistent with section
202(a) of the Act. EPA's longstanding approach to this third waiver
criterion is limited to reviewing California's feasibility assessment
and evaluating whether the opponents of the waiver have met their
burden of establishing: (1) That California's standards are
technologically infeasible, or (2) that California's test procedures
are inconsistent with the Federal test procedures. As with the other
two criteria, our review is narrow and deferential to California.
    Each of CARB's two waiver requests contained a demonstration that
its standards in each request were based on technologies currently
available or reasonably projected to be available in the lead time
given and giving consideration to costs. As such, CARB argued that its
standards did not create any issues regarding the consistency with
section 202(a) requirements. CARB's waiver requests included their
state rulemaking records for each standard, including CARB's detailed
responses to any issues raised regarding technological feasibility.
    Commenters opposed to the waiver did not argue that the 2018 HD
Warranty Amendments were not technologically feasible or that any of
the waiver requests presented inconsistent test procedures. Further,
while EPA received comment to suggest that CARB's ACT Regulation and
ZEAS Regulation were not appropriate policy choices, to the extent
commenters raised feasibility issues regarding the ACT Regulation and
ZEAS Regulation, such commenters either failed to meet the burden of
proof to demonstrate infeasibility in light of California's
demonstration of feasibility or such comments fell beyond the scope of
EPA's technological feasibility review. As explained in detail below,
based on our examination of the record, EPA finds that the commenters
have failed to meet their burden of proof as to the third prong.
    In addition, certain commenters asserted that, even if the
standards were actually feasible, EPA should nonetheless deny the
waiver based on the lead time and stability requirements for certain
federal heavy-duty vehicle standards found in section 202(a)(3)(C) of
the Act. These commenters claim that because the third waiver criterion
requires California's standards to be ``consistent with'' section
202(a), California must necessarily comply with section 202(a)(3)(C),
as that is a sub-provision of 202(a). This argument is inconsistent
with the plain text of the statute. Congress used the phrase
``consistent with,'' not ``compliant with.'' The statutory phrase
``consistent with'' indicates that California's standards should be
congruent and compatible with section 202(a), which requires that
Federal standards provide adequate lead time and consider cost. Thus,
EPA interprets this prong of the waiver analysis to require
California's standards to be feasible. The statute does not, however,
obligate California to comply with provisions of section 202(a)
directed solely at the development and design of federal standards.
This would make little sense given Congress' intent to set up two motor
vehicle programs in title II--with California's program dedicated to
address the state's air quality problems and serve as a testing ground
for motor vehicle emissions policy designs and technologies. If exactly
the same requirements and conditions apply to both the Federal and the
California programs, then they would necessarily overlap extensively if
not completely, and California could not serve as the testing ground
that Congress intended. Further, applying some of the language in
202(a) to California standards would directly conflict with the text
and intent of the waiver provisions in section 209. For those reasons,
for over five decades, EPA has consistently granted waivers to
California without assessing compliance with section 202(a)(3)(C), with
a single exception (in 1994).
    The commenters' argument regarding section 202(a)(3)(C) fails for a
number of additional reasons. That provision, which requires at least
four years of lead time and three years of stability, is a companion to
a specific Federal standard-setting mandate, section 202(a)(3)(A). That
mandate is for EPA to promulgate certain heavy-duty criteria pollutant
standards that reflect the greatest degree of emission reduction
achievable giving appropriate consideration to a number of factors.
Congress paired the mandated stringency with the lead time and
stability requirements. By contrast, California may adopt state
standards that are ``in the aggregate'' at least as protective as the
Federal standards. As such, California is also not obligated to comply
with either the maximum stringency requirements or the companion lead
time provision in section 202(a)(3)(C) to provide the four years of
lead time and three years of stability that Congress determined was
needed for the federal market.
    This plain text reading is well-supported by the history and
purpose of the Act and is also consistent with administrative and
judicial precedents. Commenters rely heavily on EPA's single contrary
decision in a 1994 medium-duty vehicle waiver (1994 MDV waiver) even
though the interpretation contained in that decision was inconsistent
with EPA's historical practice in waiver decisions both before and
after 1994.\149\ Indeed, by 2012 EPA had indicated that it did not
believe section 202(a)(3)(C) applied to California's heavy-duty engines
and vehicle standards and issued a decision consistent with its
historical practice.\150\ We acknowledge that the 1994 MDV waiver took
a different position on this issue than we do today, but as explained
below, we believe that our practice, both before and after the 1994 MDV
waiver, represents the best understanding of the statute. Importantly,
the interpretation in the 1994 MDV waiver is inconsistent with the
plain text of the statute, as discussed below. In this action, EPA is
therefore taking an approach similar to its approach both before and
after the 1994 MDV waiver, and different from the 1994 MDV waiver.\151\
EPA believes that its historical practice and application of the
``consistency with section 202(a)'' language is permissible and is the
best interpretation of the statute based on all the relevant factors.
Additionally, commenters also mistakenly rely on the D.C. Circuit's
opinion in American Motors Corp. v. Blum, 603 F.2d 978 (D.C. Cir. 1979)
(Blum). Blum addressed a different provision of the CAA and is
distinguishable from the instant waivers.
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    \149\ See 77 FR 9239, 9249 (February 16, 2012); 46 FR 22302,
22304 (1981).
    \150\ 77 FR at 9239. Moreover, in October 2000, EPA informed
California of the intent to ``conduct a new evaluation of . . .
arguments . . . in regard to whether the lead time provisions of the
Act apply to California. . . . [As well as] evaluate the
applicability of the stability requirement in Section
202(a)(3)(C).'' Letter from Margo Oge, Director, Office of
Transportation and Air Quality, to Michael Kenny, CARB Executive
Officer (Oct. 24, 2000).
    \151\ FCC v. Fox Television Stations, Inc., 556 U.S. 502 (2009).
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    The balance of this section begins with a discussion of EPA's
longstanding approach to the third waiver criterion and relevant case
law (III.D.1). We then

summarize the positions of CARB and the commenters (III.D.2 and III.D.3
respectively). Subsequently, we evaluate the waiver requests under the
historical approach, finding that those opposed to the waiver have
failed to meet their burden of proof (III.D.4). We then explain why,
contrary to the commenters' arguments, the statutory lead time
requirements in section 202(a)(3)(C) do not apply to California
(III.D.5). A brief conclusion follows (III.D.6).
1. Historical Interpretation of Section 209(b)(1)(C)
    Under section 209(b)(1)(C), EPA must grant California's waiver
request unless the Agency finds that California standards and
accompanying enforcement procedures are ``not consistent'' with section
202(a) of the Act.\152\ Section 202(a)(1) grants EPA authority to
regulate motor vehicle emissions generally and the accompanying section
202(a)(2) specifies that those standards are to ``take effect after
such period as the Administrator finds necessary to permit the
development and application of the requisite technology, giving
appropriate consideration to the cost of compliance within such
period.'' \153\ Thus, no specific lead time requirement applies to
standards promulgated under section 202(a)(1). EPA has long limited its
evaluation of whether California's standards are consistent with
section 202(a) to determining if: (1) There is inadequate lead time to
permit the development of the necessary technology giving appropriate
consideration to the cost of compliance within that time period; \154\
or whether (2) California and Federal test procedures are incompatible
so that a single vehicle could not be subjected to both tests.\155\ EPA
has also explained that ``the import of section 209(b) is not that
California and Federal standards be identical, but that the
Administrator not grant a waiver of Federal preemption where compliance
with the California standards is not technologically feasible within
available lead time.'' \156\ Further, EPA's review is limited to the
record on feasibility of the technology. Therefore, EPA's review is
narrow and does not extend to whether the regulations under review are
the most effective or whether the technology incentivized by
California's regulations are the best policy choice or better choices
should be evaluated. The Administrator has thus long explained that
``questions concerning the effectiveness of the available technology
are also within the category outside my permissible scope of inquiry,''
under section 209(b)(1)(C).\157\ California's accompanying enforcement
procedures would also be inconsistent with section 202(a) if the
Federal and California test procedures conflicted, i.e., if
manufacturers would be unable to meet both the California and Federal
test requirements with the same test vehicle.
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    \152\ EPA must grant a waiver request unless it finds that there
is: ``[i]nadequate time to permit the development of the necessary
technology given the cost of compliance within that time period.''
H. Rep. No. 728, 90th Cong., 1st Sess. 21 (1967). ``That California
standards are not consistent with the intent of section 202(a) of
the Act, including economic practicability and technological
feasibility.'' S. Rep. No. 403, 90th Cong. 1st Sess. 32 (1967).
    \153\ CAA section 202(a)(2); H.R. Rep. No. 95-294, 95th Cong.,
1st Sess. 301 (1977) (``Also preemption could not be waived if
California standards and enforcement procedures were found not to be
`consistent with section 202(a)' (relating to the technological
feasibility of complying with these standards).'').
    \154\ Previous waivers of Federal preemption have thus stated
that California's standards are not consistent with section 202(a)
if there is inadequate lead time to permit the development of
technology necessary to meet those requirements, giving appropriate
consideration to the cost of compliance within that time. See e.g.,
36 FR 8172 (April 30, 1971) (HD MY 1972 and later MY); 38 FR 30136
(Nov. 1, 1973); 40 FR 23102, 23105 (May 28, 1975) (extending waiver
of April 30, 1971, to MY 1975 HD standards); 40 FR 30311 (July 18,
1975); 70 FR 50322 (August 26, 2005) (2007 California Heavy-Duty
Diesel Engine Standards); 71 FR 335 (Jan. 4, 2006) (2007 Engine
Manufacturers Diagnostic standards); 77 FR 9239 (February 16, 2012)
(HD Truck Idling Requirements); 79 FR 46256 (Aug. 7, 2014) (the
first HD GHG emissions standard waiver, relating to certain new 2011
and subsequent model year tractor-trailers); 81 FR 95982 (December
29, 2016) (the second HD GHG emissions standard waiver, relating to
CARB's ``Phase I'' regulation for 2014 and subsequent model year
tractor-trailers); 82 FR 4867 (January 17, 2017) (On-Highway Heavy-
Duty Vehicle In-Use Compliance Program).
    \155\ To be consistent, the California certification procedures
need not be identical to the Federal certification procedures.
California procedures would be inconsistent, however, if
manufacturers would be unable to meet the state and the Federal
requirements with the same test vehicle in the course of the same
test. See, e.g., 43 FR 32182 (July 25, 1978).
    \156\ 46 FR 22032, 22034-35 (April 15, 1981).
    \157\ 41 FR 44209, 44210 (October 7, 1976); 47 FR 7306, 7310
(February 18, 1982) (``I am not empowered under the Act to consider
the effectiveness of California's regulations, since Congress
intended that California should be the judge of `the best means to
protect the health of its citizens and the public welfare.'''
(Internal citations omitted)).
---------------------------------------------------------------------------

    In determining whether California standards are inconsistent with
section 202(a), EPA makes a finding as to whether there is inadequate
lead time to permit the development of technology that is necessary to
meet the standards for which a waiver is sought. For this finding, EPA
considers whether adequate technology is presently available or already
in existence and in-use. If technology is not presently available, EPA
will consider whether California has provided adequate lead time for
the development and application of necessary technology prior to the
effective date of the standards for which a waiver is being sought.
Additionally, the D.C. Circuit has held that ``[i]n the waiver context,
section 202(a) relates in relevant part to technological feasibility
and to federal certification requirements. The technological
feasibility component of section 202(a) obligates California to allow
sufficient lead time to permit manufacturers to develop and apply the
necessary technology. The federal certification component ensures that
the Federal and California test procedures do not impose inconsistent
certification requirements. Neither the court nor the agency has ever
interpreted compliance with section 202(a) to require more.'' \158\
---------------------------------------------------------------------------

    \158\ MEMA II, 142 F.3d 449, 463 (Emphasis added) (internal
citations omitted).
---------------------------------------------------------------------------

    Regarding the technology costs portion of the technology
feasibility analysis, when cost is at issue EPA evaluates the cost of
developing and implementing control technology in the actual time
provided by the applicable California regulations. The D.C. Circuit has
stated that compliance cost ``relates to the timing of a particular
emission control regulation.'' \159\ In MEMA I, the court addressed the
cost of compliance issue at some length in reviewing a waiver decision.
According to the court:
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    \159\ MEMA v. EPA, 637 F.2d. 1118 (D.C. Cir. 1979).

    Section 202's cost of compliance concern, juxtaposed as it is
with the requirement that the Administrator provide the requisite
lead time to allow technological developments, refers to the
economic costs of motor vehicle emission standards and accompanying
enforcement procedures. See S. Rep. No. 192, 89th Cong., 1st Sess.
5-8 (1965); H.R. Rep. No. 728 90th Cong., 1st Sess. 23 (1967),
reprinted in U.S. Code Cong. & Admin. News 1967, p. 1938. It relates
to the timing of a particular emission control regulation rather
than to its social implications. Congress wanted to avoid undue
economic disruption in the automotive manufacturing industry and
also sought to avoid doubling or tripling the cost of motor vehicles
to purchasers. It, therefore, requires that the emission control
regulations be technologically feasible within economic parameters.
Therein lies the intent of the cost of compliance requirement
(emphasis added).\160\
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    \160\ MEMA I 627 F.2d at 1118 (emphasis added). See also id. at
1114, n.40 (``[T]he `cost of compliance' criterion relates to the
timing of standards and procedures.'').

    Previous waiver decisions are fully consistent with MEMA I, which
indicates that the cost of compliance must reach a very high level
before the EPA can deny a waiver. Therefore, past decisions indicate
that the costs must be

excessive to find that California's standards are infeasible and
therefore inconsistent with section 202(a).\161\
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    \161\ See, e.g., 47 FR 7306, 7309 (Feb. 18, 1982); 43 FR 25735
(Jun. 14, 1978); 46 FR 26371, 26373 (May 12, 1981).
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    Regarding the burden of proof under the third prong, EPA has
previously stated that the third prong's feasibility determination is
limited to: (1) Whether those opposed to the waiver have met their
burden of establishing that California's standards are technologically
infeasible, including whether they include adequate lead time or (2)
that California's test procedures impose requirements inconsistent with
the Federal test procedure. Additionally, the burden of proof regarding
the cost component of feasibility also falls upon the waiver opponents.
    The scope of EPA's review under this criterion is also narrow.\162\
This is consistent with the motivation behind section 209(b) to foster
California's role as a laboratory for motor vehicle emission control,
in order ``to continue the national benefits that might flow from
allowing California to continue to act as a pioneer in this field.''
\163\ According to the D.C. Circuit, ``The history of congressional
consideration of the California waiver provision, from its original
enactment up through 1977, indicates that Congress intended the State
to continue and expand its pioneering efforts at adopting and enforcing
motor vehicle emission standards different from and in large measure
more advanced than the corresponding federal program; in short, to act
as a kind of laboratory for innovation.'' \164\ EPA has thus long
believed that California must be given substantial deference when
adopting motor vehicle emission standards because such action may
require new or improved technology to meet challenging levels of
compliance. Over 50 years ago, EPA's Administrator discussed this
deference in an early waiver decision that approved a waiver request
for California:
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    \162\ 41 FR 44208, 44210 (October 7, 1976)(``While section
209(b) requires consideration of whether the adoption of standards
by California is consistent with section 202(a), nevertheless [the
Administrator's] discretion in determining whether to deny the
waiver is considerably narrower than [his] discretion to act or not
to act in the context promulgating Federal standards under section
202(a).'').
    \163\ 40 FR 23102, 23103 (May 28, 1975) (waiver decision citing
views of Congressman Moss and Senator Murphy).
    \164\ MEMA I, 627 F.2d 1095, 1110.

    There is a well-established pattern that emission control
technology have been phased in through use in California before
their use nationwide. This pattern grew out of early recognition
that auto caused air pollution problems are unusually serious in
California. In response to the need to control auto pollution,
California led the nation in development of regulations to require
control of emissions. This unique leadership was recognized by
Congress in enacting federal air pollution legislation both in 1967
and 1970 by providing a special provision to permit California to
continue to impose more stringent emission control requirements than
applicable to the rest of the nation.\165\
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    \165\ 38 FR 10317, 10324 (April 26, 1973) (``[T]he experience of
Federal and State officials as well as the industry itself in
meeting such standards for California will facilitate an orderly
implementation of the more stringent, catalyst-forcing standards for
California.'').

    In a subsequent waiver decision approving a waiver request for
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California, the Administrator stated:

    It is worth noting . . . I would feel constrained to approve a
California approach to the problem which I might also feel unable to
adopt at the federal level in my own capacity as a regulator. The
whole approach of the Clean Air Act is to force the development of
new types of emission control technology where that is needed by
compelling the industry to ``catch up'' to some degree with newly
promulgated standards. Such an approach * * * may be attended with
costs, in the shape of a reduced product offering, or price or fuel
economy penalties, and by risks that a wider number of vehicle
classes may not be able to complete their development work in time.
Since a balancing of these risks and costs against the potential
benefits from reduced emissions is a central policy decision for any
regulatory agency under the statutory scheme outlined above, I
believe I am required to give very substantial deference to
California's judgments on this score.'' \166\
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    \166\ 40 FR 23102, 23104 (May 28, 1975). See also 78 FR 2111,
2115-16 (Jan. 9, 2013); 79 FR 46256, 46258 (Aug. 7, 2014); 81 FR
95982, 95984 (Dec. 29, 2016).

    In keeping with this deferential posture, as noted earlier, EPA's
historical interpretation of section 209(b) has also been to assess
whether California's program of motor vehicle emission standards as a
whole provides for adequate lead time consistent with section 202(a).
This is because EPA's long-standing interpretation is that the phrase
``State standards'' in section 209(b)(1) means the entire California
new motor vehicle emissions program.\167\ Similar to the second waiver
criterion, EPA has also historically viewed the third waiver
criterion's feasibility analysis as a whole-program assessment, i.e.,
one that ensures manufacturers have sufficient lead time to comply with
the program's standards as a whole, accounting for the interactions
between technologies necessary to meet both new and existing standards,
and any interactions between those technologies that would affect
feasibility.\168\ EPA's assessment under section 209(b)(1)(C) is thus
not in practice a standard-by-standard review. Rather it involves an
analysis of feasibility that builds on prior analyses of feasibility
and any impacts of the new standards on the feasibility of the
remainder of the program.\169\
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    \167\ 74 FR 32744, 32749 (July 8, 2009); 70 FR 50322 (Aug. 26,
2005); 77 FR 9239 (Feb. 16, 2012); 78 FR 2112, 2123 (Jan. 9, 2013).
    \168\ As a practical matter, EPA's consideration of the third
waiver prong, like the first waiver prong, does not necessitate in
every case that EPA re-review previously-approved aspects of
California's program--for example, where it is evident that new
standards will not interact with existing ones. But where a new
waiver request might affect one of EPA's previous assessments under
any of the waiver criteria, EPA reviews the program as a whole--or
any aspect necessary to confirm alignment with the statutory text.
87 FR at 14361 and n.266.
    \169\ Id. at 14361. The feasibility assessment conducted for a
new waiver request focuses on the standards in that request but
builds on the previous feasibility assessments made for the
standards already in the program and assesses any new feasibility
risks created by the interaction between the standards in the
petition and the existing standards.
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    EPA has also long recognized that the laboratory role and nature of
California's standards may result in California amending or revising
requirements after the grant of a waiver, or otherwise adjusting the
implementation of the waived standards as circumstances dictate.\170\
EPA's waiver practice when California amends a previously waived
standard or accompanying enforcement procedure is to consider whether
such an amendment is within the scope of a previously granted waiver or
requires a new waiver. If EPA considers the amendment as within the
scope of a prior waived standard, then the Agency reviews the amendment
to determine that it does not undermine California's determination that
its standards in the aggregate are as protective of public health and
welfare as applicable Federal standards, does not affect the
regulation's consistency with section 202(a), and raises no new issues
affecting EPA's previous waiver decisions.
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    \170\ See e.g., 68 FR 19811 (April 22, 2003), 71 FR 78190
(December 28, 2006), 75 FR 44948 (July 30, 2006).
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    Decisions from the D.C. Circuit provide guidance regarding the lead
time requirements of section 202(a). Section 202(a)(2) states that
``any regulation prescribed under paragraph (1) of this subsection (and
any revision thereof) shall take effect after such period as the
Administrator finds necessary to permit the development and application
of the requisite technology, giving appropriate

consideration to the cost of compliance within such period.'' For
example, in Natural Resources Defense Council v. EPA (NRDC), the court
reviewed claims that EPA's PM standards for diesel cars and light
trucks were both too stringent and not stringent enough. In upholding
---------------------------------------------------------------------------
the EPA standards, the court concluded:

    Given this time frame [a 1980 decision on 1985 model year
standards]; we feel that there is substantial room for deference to
the EPA's expertise in projecting the likely course of development.
The essential question in this case is the pace of that development,
and absent a revolution in the study of industry, defense of such a
projection can never possess the inescapable logic of a mathematical
deduction. We think that the EPA will have demonstrated the
reasonableness of its basis for projection if it answers any
theoretical objections to the [projected control technology],
identifies the major steps necessary in refinement of the
technology, and offers plausible reasons for believing that each of
those steps can be completed in the time available.\171\
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    \171\ NRDC, 655 F.2d 318, 331 (D.C. Cir. 1981).

    Another key case addressing the lead time requirements of section
202(a) is International Harvester v. Ruckelshaus (International
Harvester). In International Harvester, the court reviewed EPA's
decision to deny applications by several automobile and truck
manufacturers for a one-year suspension of the 1975 emission standards
for light-duty vehicles. In the suspension proceeding, the
manufacturers presented data which, on its face, showed little chance
of compliance with the 1975 standards, but which, at the same time,
contained many uncertainties and inconsistencies regarding test
procedures and parameters. In a May 1972 decision, the Administrator
applied an EPA methodology to the submitted data, and concluded that
``compliance with the 1975 standards by application of present
technology can probably be achieved,'' and so denied the suspension
applications.\172\ In reviewing the Administrator's decision, the court
found that the applicants had the burden of providing data showing that
they could not comply with the standards, and if they did, then EPA had
the burden of demonstrating that the methodology it used to predict
compliance was sufficiently reliable to permit a finding of
technological feasibility. In that case, EPA failed to meet this
burden.
---------------------------------------------------------------------------

    \172\ International Harvester v. Ruckelshaus, 478 F 2d. 615, 626
(D.C. Cir. 1979).
---------------------------------------------------------------------------

    In NRDC the court pointed out that the court in International
Harvester ``probed deeply into the reliability of EPA's methodology''
because of the relatively short amount of lead time involved (a May
1972 decision regarding 1975 MY vehicles, which could be produced
starting in early 1974), and because ``the hardship resulting if a
suspension were mistakenly denied outweigh[s] the risk of a suspension
needlessly granted.'' \173\ The NRDC court compared the suspension
proceedings with the circumstances concerning the diesel standards
before it: ``The present case is quite different; `the base hour' for
commencement of production is relatively distant, and until that time
the probable effect of a relaxation of the standard would be to
mitigate the consequences of any strictness in the final rule, not to
create new hardships.'' \174\ The NRDC court further noted that
International Harvester did not involve EPA's predictions of future
technological advances, but an evaluation of presently available
technology.
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    \173\ NRDC, 655 F.2d 318, 330.
    \174\ Id. The ``hardships'' referred to are hardships that would
be created for manufacturers able to comply with the more stringent
standards being relaxed late in the process.
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2. CARB's Discussion of the Regulations' Consistency With Section
202(a) in the Waiver Requests
    Each of CARB's waiver requests demonstrated that its standards were
based on technologies currently available or reasonably projected to be
available in the lead time provided under each regulation, taking into
consideration costs and other factors. As such, CARB argued that its
standards did not create any issues regarding consistency with section
202(a) requirements. CARB's waiver requests included the state
rulemaking records for each standard, including CARB's response to any
issues raised regarding technological feasibility. In this section
III.D.2, we present CARB's arguments for each of its waiver requests in
turn. In the following section III.D.3, we present the commenters
arguments. EPA has reviewed the information submitted to the record of
this proceeding to determine whether the parties opposing the waiver
requests have met their burden to demonstrate that the respective
standards (and accompanying enforcement procedures) are not consistent
with section 202(a). As explained in subsection III.D.4 below, EPA has
evaluated each of the waiver requests under the test historically used
and is concluding that the opponents of the waiver requests have not
met the burden of proof regarding the third waiver prong. EPA also
discusses, in subsection III.D.5, why, contrary to the commenters'
arguments, the statutory lead time requirements in section 202(a)(3)(C)
do not apply to California.
a. 2018 HD Warranty Amendments
    CARB's waiver request noted that the elements of the 2018 HD
Warranty Amendments that lengthen the warranty periods present no
issues regarding technical feasibility or lead time. At the outset,
CARB noted that although manufacturers are incentivized to produce and
use more durable emission related components and systems in 2022 and
beyond, the manufacturers are not compelled to do so. Because
manufacturers may elect to use their existing components to comply with
the regulations, CARB contended that EPA's prior findings of adequate
technical feasibility and lead time found within EPA's waiver for
California's 2007 and later model years remains applicable and
dispositive. CARB also noted that no commenters raised objections
regarding the feasibility and lead time of the extended emission
warranty periods during its rulemaking. CARB noted similar findings
regarding the new minimum allowable maintenance schedules. CARB also
noted its belief that it appropriately considered the costs of the 2018
HD Warranty Amendments and that it is not aware of any test procedure
consistency issues.\175\
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    \175\ 2018 HD Warranty Amendments Support Document at 20-23.
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b. ACT, ZEAS, and ZEP Certification Regulations
    CARB's ACT Regulation waiver request provided information
pertaining to consistency with section 202(a)'s feasibility
requirements for each of the three regulations covered by the request.
CARB noted that the ACT Regulation's requirements that new 2024 MY
medium- and heavy-duty ZEVs be produced and delivered for sale to
ultimate purchasers in California are consistent with section 202(a)
because the required technology already exists.\176\ CARB's waiver
request also

noted that the ACT Regulation implements the ZEV sales requirement
through a credit and deficit mechanism, whereby manufacturers' deficits
are generated commencing with the 2024 model year based, in part, on
their annual sales of onroad vehicles with gross vehicle weight ratings
(GVWRs) exceeding 8,501 pounds produced and delivered for sale in
California. Manufacturers may earn credits by producing and delivering
for sale, to ultimate consumers in California, certain types of ZEV
vehicles, and subsequently there is a banking and trading system.\177\
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    \176\ ACT/ZEAS/ZEP Waiver Support Document at 31-32 (``As
described in the ACT regulation's rulemaking record, medium- and
heavy-duty ZEVs are currently commercially available . . . This
includes vehicles from companies such as BYD, Motiv, Phoenix
Motorcars, XOS, and others. Traditional manufacturers of heavy-duty
vehicles, including Freightliner, Kenworth, Peterbilt, and Volvo,
are currently demonstrating heavy-duty ZEVs in California, with the
intent to launch commercial products by 2024. 15 manufacturers are
offering more than 50 different ZEV truck and bus configurations,
other than transit buses, from Class 3 through Class 8 through the
Hybrid and Zero-Emission Truck and Bus Voucher Incentive Program
(HVIP). HVIP has provided funding for 2,456 zero-emission trucks and
buses and 2,593 hybrid trucks since 2010 to support the long-term
transition to zero-emission vehicles in the heavy-duty market. These
commercially available zero-emission trucks and buses cover a wide
variety of vocations and duty cycles; some vehicles available today
include delivery vans, school buses, refuse trucks, cutaway
shuttles, terminal tractors, and passenger vans.'').
    \177\ Id. at 7-10
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    Similarly, regarding the ZEAS Regulation, CARB noted that the
technology needed to produce zero-emission airport shuttle vehicles
currently exists.\178\ Finally, CARB also noted that the ZEP
Certification Regulation, requiring manufacturers to conduct energy-
capacity testing for batteries used in zero-emission powertrains,
presents no issues of technical feasibility because the specified test
procedure only requires use of commercially available test
equipment.\179\
---------------------------------------------------------------------------

    \178\ Id. at 33.
    \179\ Id. at 34-36.
---------------------------------------------------------------------------

    In addition to showing that the required technology is already
commercially available, CARB noted that it appropriately considered the
cost of each of the regulations, including the incremental capital
costs as well as total costs of ownership (TCO) to potential vehicle
owners.\180\ CARB noted that its Staff Report for the ACT Regulation
included an estimate that the average incremental vehicle price for
certain new ZEVs would be 30 percent to 60 percent higher than a
comparable combustion-powered vehicle in certain years, with costs for
these vehicles declining over time. Further, CARB noted that it had
evaluated the TCO for purchasing an ACT compliant vehicle and all other
related costs including fuel, maintenance, Low Carbon Fuel Standard
revenue, and infrastructure, and noted that ZEVs in appropriate duty
cycles can see a positive TCO by 2024 or sooner and reported similar
TCO positive results for ZEAS by 2028.\181\ CARB also noted that
neither the ACT, ZEAS, nor ZEP Certification Regulations present any
issues of test procedure inconsistency because there are no analogous
Federal requirements and, as such, engines manufacturers are not
precluded from complying with the California and Federal test
requirements with one test engine or vehicle.\182\
---------------------------------------------------------------------------

    \180\ Id. at 36-38 (ACT), at 38-39 (ZEAS), and 39-40.
    \181\ Id.
    \182\ Id. at 39.
---------------------------------------------------------------------------

3. Comments on Section 209(b)(1)(C)
    EPA received a range of comments on each of CARB's regulations
relating to the third criteria. Regarding the ACT Regulation, EPA
received a comment that stated that the applicable technological
feasibility criteria to apply is found in section 202(a)(3)(A).\183\
This commenter maintains that CARB must demonstrate that the ACT
standards ``are achievable through reasonably available technology, and
must similarly consider related costs, energy, and safety factors'' and
that CARB cannot meet this obligation. This commenter notes two
separate studies regarding the current availability of electric and
hydrogen fuel cell medium and heavy-duty trucks, and that one of the
studies noted that electric trucks using present lithium battery
technology would need levels of energy density and battery storage
capacity to support a daily ranger of 600 miles at level that would
weigh 6300 kg and cost approximately $180,000. This commenter maintains
that CARB did not consider several factors including charging networks
as well as safety issues and legal restrictions on commercial activity
at rest stops. The commenter maintains that because these factors were
not considered by CARB then it does not meet the requirements of
section 202(a)(3)(A).\184\ EPA also received supplemental comment from
CARB that was submitted in response to comments submitted in opposition
to the waiver for the ACT Regulation. CARB noted that several comments
fail to satisfy opponents' burden of proof because they misunderstand
the necessary showing or make no showing at all.\185\ CARB also
recognized the challenges to the technical feasibility of the ACT
Regulation raised by one commenter but noted that no commenter has
disputed CARB's evidence that the technology need to comply with the
ACT Regulation already exists.\186\ In addition, CARB responded to
comments regarding ZEV constraints associated with operating ranges and
performance characteristics.\187\ Finally, CARB noted several
commenters' assertions that CARB failed to account for and accurately
assess a number of different costs associated with the ACT Regulation
(e.g., costs of manufacturing and maintaining ZEVs, battery replacement
costs, reduced operational hours due to needs to recharge, etc.) and
pointed to its rulemaking record and submissions to EPA that address
such claims. And in any case CARB maintained that these commenters have
not introduced evidence that establishes that the compliance costs as
so excessive as to make the standards infeasible.\188\
---------------------------------------------------------------------------

    \183\ Valero at 4. This commenter does not discuss the phase
``greatest degree of emission reduction achievable through
application of technology'' in 202(a)(3)(A)(i) and whether and how
it is related to its cited language regarding the consideration to
``cost, energy, and safety factors.''
    \184\ Id. at 4-6.
    \185\ CARB Supplemental Comments at 11. CARB noted both EMA and
WSPA comments that do not provide any elaboration of why the lead
time provided is not reasonable. ``[S]ection 209(b) does not give
[the Administrator] the latitude to review procedures at the State
level, and the EPA hearing is not the proper forum in which to raise
these objections. Similarly, objections pertaining to the wisdom of
California's judgment on various public policy matters are beyond
the [Administrator's] scope of inquiry.'' 43 FR 32184 citing 42 FR
44209, 44210 (October 7, 1976).
    \186\ Id. at 11-12.
    \187\ Id. at 12. (CARB's analysis found that although certain
market segments presented challenges, a large number of other
segments are well suited for electrification across the medium- and
heavy-duty truck market, including refuse trucks, yard trucks and
box trucks within the Class 8 vocational market. CARB expects that
the demand for heavy-duty ZEVs will significantly increase as ZEV
technology improves, resulting in increased operating ranges and
decreased vehicle prices.''). CARB also provided updated data and
noted recently enacted federal action.
    \188\ Id. at 12-13 (Citing the ACT waiver request at 31-39, ACT
ISOR at IX-8, ACT FSOR at IX-23-IX-24, IX-27-IX-28, ACT FSOR at 105,
192, 204-222, 269-274 (respond to comments asserting that CARB did
not accurately assess cost impacts of the ACT Regulation).
---------------------------------------------------------------------------

    Many of the comments EPA received on the third prong also focused
not on whether the standards under review were actually infeasible
under section 202(a)(2), but on whether CARB, to be consistent with
section 202(a), must provide the four years of lead time and three
years of stability for standards applicable to new heavy-duty vehicles
and engines required under section 202(a)(3)(C). Commenters objected to
the 2018 HD Emission Warranty Amendments and the ACT Regulation on the
grounds that the third waiver criterion requires ``consistency'' with
every provision of section 202(a) and therefore, by the text of the
statute, CARB must provide four years of lead time and three years of
stability for its new heavy-duty vehicle and engine

standards.\189\ In response, supporters of the regulations argued that
``consistency'' does not require identicality with lead time and
stability requirements imposed on EPA. Such a strict imposition, they
argued, would frustrate Congress' intent to give California flexibility
and deference to create innovative standards that are more stringent
than the Federal standards.\190\ Identicality also cannot be required,
they argued, because it would be impossible for certain sub-provisions
of section 202(a) to apply to CARB.\191\ In response, one commenter
argued that, even if some provisions of 202(a) are relevant only to EPA
and not CARB, ``consistency'' still requires CARB to abide by relevant
provisions, such as 202(a)(3)(C)'s lead time and stability
requirements.\192\
---------------------------------------------------------------------------

    \189\ EMA Initial Comments at 4-5, 6-7; EMA Supplemental
Comments at 1. NADA at 2; WSPA at 2.
    \190\ See, e.g., CARB Initial ACT Comments at 17-18; CARB
Initial Omnibus Low NOx Comments at 9 (submitted as Exhibit 4 of
CARB's Initial ACT Comments); CARB Supplemental Comments at 7-8;
Environmental and Public Health Organizations at 22-24. EPA notes
CARB's contention that section 202(a)(3)(C) was designed with
specific purposes by Congress, and that such purposes were, in part,
to minimize the burden associated with new standards and the
associated new designs of affected vehicles and that in many
instances CARB's regulations do not require a redesign of existing
vehicles. (``The clear purpose of Section 202(a)(3)(C) is to protect
manufacturers with respect to specific EPA standards, from having to
perform redesigns without four years of lead time or more often than
every three years.'' But ``the year-on-year changes in the legal
obligations imposed by ACT are different from those imposed by more
traditional vehicle emission standards--the kind of standards
Congress had in mind when it drafted Section 202(a)(3)(C).'' See
CARB Supplemental Comments, 9-11 and CARB Initial ACT Comments at
19-22. As explained below, EPA finds its textual assessment of
202(a)(3)(C) to be sufficient to determine the inapplicability to
California and that it is not necessary to examine the underpinnings
of this aspect of CARB's argument.
    \191\ See, e.g., CARB Initial Omnibus Low NOX
Comments at 16-17 (submitted as Exhibit 4 of CARB's Initial ACT
Comments); CARB Supplemental Comments at 7-8; Environmental and
Public Health Organizations at 20-21; ACT/ZEAS/ZEP Waiver Support
Document at 31-32 (citing the ACT FSOR at 131).
    \192\ EMA Supplemental Comments at 4 (``Of course, all of the
provisions of section 202(a) are directed on their face to EPA, not
California, and that is no reason to distinguish one part of section
202(a) from another. Consistency means that CARB must abide by and
avoid contradicting those provisions that are relevant. CARB agrees
that it must abide by the technology lead-time requirement directed
at EPA in section 202(a)(2), and CARB must equally abide by the
four-year lead-time requirement in section 202(a)(3)(C) that is
directed at EPA in precisely the same way. Neither of those
provisions is uniquely applicable to EPA'').
---------------------------------------------------------------------------

    EPA also received comment that four years of lead time is supported
by Federal case law and EPA's prior waiver decisions. In particular,
one commenter noted EPA's 1994 MDV waiver decision document, which
found that CARB is subject to 202(a)(3)(C)'s four-year lead time
requirement.\193\ That decision considered the plain text and
congressional intent of the CAA as well as the 1979 D.C. Circuit case,
American Motors Corporation v. Blum (Blum), which incorporated a
specific minimum two-year lead time from CAA section 202(b)(1)(B) into
the 202(a)(2) general technological feasibility analysis. The commenter
explained that the D.C. Circuit in Blum ``found that the
Congressionally-specified lead time requirement was implicitly
incorporated into section 202(a)(2)'' and argues that Blum's logic
applies equally to section 202(a)(3)(C).\194\
---------------------------------------------------------------------------

    \193\ EMA Initial Comments at 3; EMA Supplemental Comments at 2-
3.
    \194\ EMA Initial Comments at 7-9 (``The D.C. Circuit's
reasoning in Blum applies with equal force here: failing to apply
the minimum four-year leadtime requirement would frustrate the
leadtime that Congress explicitly found to be necessary for [heavy-
duty on-highway] standards.''); EMA Supplemental Comments at 2-3
(``In addition to the general technology-based lead-time required
for all vehicles and engines, section 202(a)(3)(C) is aimed
specifically at the heavy-duty industry, which is not vertically
integrated, involves much lower production volumes, is more capital
intensive, requires longer planning and product development
timelines, and requires longer time periods to recoup large capital
investments. See, e.g., Hearing on S.1630 Before Subcomm. on Env't
Protection, 101st Cong. 312-13 (1989). These considerations make
lead-time necessary regardless of whether it is EPA or CARB that
adopts the applicable standards with which the industry must make
investments to comply. Thus, as EPA rightly concluded in 1994, the
section 202(a)(3)(C) lead-time requirement is no different than the
lead-time provision at issue in Blum.'').
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4. California's Standards Are Consistent With Section 202(a) Under
EPA's Historical Approach
    As explained above, EPA has historically applied a consistency test
under section 202(a) that calls for the Administrator to first review
whether adequate technology already exists, and if it does not, whether
there is adequate time to develop and apply the technology before the
standards go into effect.\195\ After a review of the record,
information, and comments received in this proceeding, EPA has
determined that the opponents of the waiver request for CARB's
regulations have not demonstrated that these regulations are
inconsistent with section 202(a). As noted above, CARB's waiver
requests indicated that control technology either presently exists or
is in use, and opponents do not provide information that sufficiently
meets their burden of proof.
---------------------------------------------------------------------------

    \195\ EPA has previously stated that the determination is
limited to whether those opposed to the waiver have met their burden
of establishing that California's standards are technologically
infeasible, or that California's test procedures impose requirements
inconsistent with the Federal test procedure. See, e.g., 38 FR 30136
(Nov. 1, 1973); 40 FR 30311 (July 18, 1975); 71 FR 335 (Jan. 4,
2006) (2007 Engine Manufacturers Diagnostic standards); 70 FR 50322
(August 26, 2005) (2007 California Heavy-Duty Diesel Engine
Standards); 77 FR 9239 (February 16, 2012) (HD Truck Idling
Requirements); 78 FR 2111, 2132 (Jan. 9, 2013); 79 FR 46256 (Aug. 7,
2014) (the first HD GHG emissions standard waiver, relating to
certain new 2011 and subsequent model year tractor-trailers); 81 FR
95982 (December 29, 2016) (the second HD GHG emissions standard
waiver, relating to CARB's ``Phase I'' regulation for 2014 and
subsequent model year tractor-trailers); 82 FR 4867 (January 17,
2017) (On-Highway Heavy-Duty Vehicle In-Use Compliance Program).
---------------------------------------------------------------------------

    The rationale supporting EPA's determination is organized as
follows. Applying its historical approach of section 209(b)(1)(C) to
CARB's regulations, EPA first examines whether the opponents of the
waiver requests at issue have met their burden of proof to demonstrate
that the regulations are not technologically feasible, within the lead
time provided and giving consideration to cost. We present our analysis
for each of the regulations in the two waiver requests (the 2018 HD
Warranty Amendments, the ACT, ZEAS, and the ZEP Certification
Regulations), in subsections III.D.4.a and b below. We conclude, under
EPA's historical approach to the third waiver criterion, that the
opponents of the waiver have not met their burden of proof.
a. 2018 HD Warranty Amendments
    As previously described, the 2018 HD Warranty Amendments lengthen
the warranty periods for new heavy-duty vehicles and engines commencing
with the 2022 model year. Manufacturers can choose to meet the new
warranty periods either through installing more durable emission
related components (with an associated increase in cost) or by relying
upon existing emission related components designed to meet applicable
emission standards and cover any increase in costs associated with
additional emission warranty claims and repairs due to the increase in
the warranty periods. Opponents of a waiver for the 2018 HD Warranty
Amendments do not claim that the regulation is actually infeasible
under EPA's approach. If EPA had received such comments, it would be
appropriate to evaluate whether more durable emission related
components are technologically feasible (giving consideration to the
cost of such components) and to evaluate the costs for manufacturers to
choose to use existing components and cover the costs of additional
emission warranty related claims.

    During the course of EPA's waiver proceeding, we did not receive
any comments or evidence to suggest, let alone meet the burden of
proof, that the emission control technology needed for the new extended
emission warranty periods and the new minimum allowable maintenance
schedules did not meet the consistency with section 202(a) requirement.
    Likewise, EPA received no comments concerning CARB's separate point
regarding the options within California's regulation that incentivize
manufacturers to produce more durable emission related parts. EPA
received no comments that this separate compliance strategy, of using
existing emission control parts and covering the costs of any
additional emission warranty claims, was infeasible or too costly. In
addition, we did not receive any comments or evidence during the waiver
proceeding to suggest such concerns were raised during California's
rulemaking. CARB also noted that there are no test procedure
consistency issues. EPA has not received comment during the waiver
comment period regarding any of these matters.\196\
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    \196\ The record for this waiver proceeding also includes the
ISOR and FSOR for CARB's 2018 HD Warranty Amendments rulemaking
(included in the 2018 HD Warranty Amendments Waiver docket at EPA-
HQ-OAR-2022-0330-0006 and EPA-HQ-OAR-2022-0330-0014). EPA has
received no comment that questions CARB's findings.
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    Therefore, based on the record before us, EPA cannot find that the
opponents of the 2018 HD Warranty Amendments waiver have met their
requisite burden of proof to demonstrate that such requirements are
inconsistent with section 202(a). Thus, EPA cannot deny CARB's 2018 HD
Warranty Amendments waiver request on this basis.\197\
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    \197\ EPA evaluates the lead time associated with a CARB's
regulation by in part examining the date of CARB's adoption of the
regulation and when manufacturers are required to meet the
regulation. EPA is guided both by the amount of lead time provided
and by the principles set forth in cases such as International
Harvester and NRDC. EPA finds no evidence in the record that
manufacturers were unable to comply with CARB's requirements that
commenced with the 2022 model year.
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b. ACT, ZEAS, and ZEP Certification Regulations
    At the outset, EPA notes two key principles among others that guide
EPA's evaluation of technological feasibility within section
209(b)(1)(C). As previously explained, first, EPA considers whether
adequate technology is either presently available or already in
existence and in-use. If technology is not presently available, EPA
will consider whether California has provided adequate lead time for
the development and application of necessary technology prior to the
effective date of the standards for which a waiver is being sought.
Second, EPA has thus long believed that California must be given
substantial deference when adopting motor vehicle emission standards
because such action may require new or improved technology to meet
challenging levels of compliance and that California plays a laboratory
role. EPA is guided both by the amount of lead time provided by CARB
and principles set forth in cases such as International Harvester and
NRDC. This is EPA's historical approach, and it is applied in this
decision. As such, the requirements of section 202(a)(3)(A) do not
apply to California. Nevertheless, the factors such as energy and
safety found in section 202(a)(3)(A) have been addressed by California
and are part of the record here.
    EPA finds that CARB's assessment of technology, lead time and cost
was based on reasonable assumptions and EPA has received no subsequent
comment during the waiver proceeding to indicate otherwise. Although
EPA received comment suggesting that EPA's technological feasibility
analysis should be performed under the criteria of section
202(a)(3)(A), the Agency explains below that section 202(a)(3)(A) does
not apply to California. As also explained, section 202(a)(3)(A) was
designed by Congress to explicitly address EPA rulemaking activities.
As such, EPA's historical waiver approach of applying section
202(a)(2), for purposes of assessing technological feasibility, lead
time and cost as required by section 209(b)(1)(C), also applies to
California's heavy-duty vehicle and engine emission standards.
Nevertheless, EPA has examined the waiver opponents comments regarding
the requisite battery technologies (including weight, infrastructure,
and safety issues).\198\
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    \198\ EPA finds that it is beyond the scope of EPA's review to
examine the feasibility of CARB's standards outside of California,
including in states adopting CARB's standards (section 177 states).
See 78 FR 2143, 74 FR 32744.
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    CARB's ACT Regulation waiver request provided information
pertaining to consistency with section 202(a) for each of the three
regulations covered by the request. CARB noted that the ACT
Regulation's requirements that new 2024 MY medium- and heavy-duty ZEVs
be produced and delivered for sale to ultimate purchasers in California
are consistent with section 202(a) because the required technology
already exists.\199\ In addition, although EPA received limited cost
data from a commenter, EPA finds no requisite evidence in the record or
comments that suggest that such technology does not exist at reasonable
costs (including the costs to consumers), or that ZEV trucks and buses
that cover a variety of vocation and duty cycles are not commercially
available.\200\ EPA also notes that the ACT Regulation includes deficit
and credit generation provisions whereby manufacturers have the
flexibility to phase in differing products over time and mitigate
deficits in later model years or through trading. Further, in examining
costs where technologies already exist, EPA is also guided by how costs
are juxtaposed with lead time. Costs in this context relates to the
timing of a particular emission control technology rather than to
broader considerations.\201\ Opponents of the waiver have not met their
burden of proof to demonstrate the ACT Regulation is inconsistent with
section 202(a). The commenters have not demonstrated, based on EPA's
assessment of the record on the overall feasibility of technology and
costs, that a disruption to the heavy-duty vehicle and engine
manufacturing industry would occur or that there is an undue burden on
this industry as a result of the ACT Regulation. The record includes
evidence of the ability of manufacturers to introduce certain service
classes of vehicles that may have availability of central charging and
lower costs, and in a timeframe and sequence that meets the ZEV phase-
in requirements of the ACT Regulation. Further, while the heavy-duty
vehicles that meet the ACT Regulation includes initial development
costs and costs of integrating the technology to the vehicles (the cost
of compliance) and other higher upfront costs for certain vehicles and
in certain years, than traditional or conventionally fueled vehicles,
the opponents of the waiver have not met their burden of proof to
demonstrate that such costs of compliance are prohibitive. Beyond the
technological feasibility of the emission controls needed to meet the
applicable standards, EPA is also sensitive to the costs of the
vehicles as well as the TCO of such vehicles. There is no indication
that the ZEV vehicles today and projected to meet the ACT Regulation
would be experience cost increases close in magnitude to prohibitive
levels. Additionally, EPA agrees with CARB

that the opponents of the waiver that asserted claims regarding various
battery issues such as replacement costs, weight, and inabilities to
travel longer distances have not demonstrated that the compliance costs
are so excessive to make the standards infeasible. EPA notes that CARB,
in adopting the ACT Regulation, performed a market segment analysis for
87 market segments that use Class 2b-8 trucks, and assessed their
suitability for electrification based on issues including payload,
daily operational ranges, infrastructure access, and space
considerations.\202\ EPA finds that CARB has reasonably identified
technologies and vehicle applications that are available in the near
term as well as reasonable evidence that the performance and demand for
heavy-duty ZEVs will significantly improve as technology evolves.
Separately, EPA notes that CARB has submitted extensive information to
EPA regarding its assessment of battery technology--including safety,
the suitability of the grid and charging infrastructure, and related
issues related to the ACT Regulation as a policy choice.\203\
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    \199\ ACT/ZEAS/ZEP Waiver Support Document at 31-32.
    \200\ Id. at 18.
    \201\ MEMA I at 1118. (``Congress wanted to avoid undue economic
disruption in the automotive manufacturing industry and also sought
to avoid doubling or tripling the cost of motor vehicles to
purchasers.'').
    \202\ CARB Supplemental Comments at 12 (see appendix E to the
ACT ISOR).
    \203\ See CARB's FSOR at 9-10 (discussion of alternative fueled
vehicles and regulatory suggestion of ultra-low NOX
rather than the ZEV levels on ACT, in context of grid readiness);
FSOR at 124-127 (grid resiliency); FSOR at 103 (CARB notes ``The
Board approved the regulation without off-ramps to ensure that
vehicle manufacturers, suppliers, and infrastructure manufacturers
have certainty in making long-term investments needed to ensure
large-scale deployment of ZEVs in California. The regulation's
structure gives manufacturers flexibility to bank credits, shift
sales between weight classes, and trade credits with other
manufacturers. These flexibility provisions give manufacturers
assurance that they can comply and does not introduce the
uncertainty associated with potential off-ramps.''); ACT Waiver
Request at 31-39. See also, ACT ISOR at IX-8, IX-23 to IX-24, IX-27
to IX-28, 10, 192, 204-22, and 269-74.
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    Therefore, the phase-in of ZEV sales percentages in the ACT
Regulation falls within the feasibility tests set forth in
International Harvester and NRDC and the opponents of the waiver have
not met their burden of proof to refute CARB's analysis and
projections. Similarly, EPA finds no evidence in the record that
suggests that technology needed to produce zero emission airport
shuttle vehicles to meet the ZEAS Regulation does not exist or that
manufacturers would not be able to meet the ZEP Certification
Regulation.\204\ To the extent that commenters suggest preferred
feasible alternatives but do not argue that the CARB regulations are
technologically infeasible themselves, EPA again notes that CARB has
significant discretion in the policy choices it makes to address
California's air pollution problems.\205\ ``The structure and history
of the California waiver provision clearly indicate a Congressional
intent and an EPA practice of leaving the decision on ambiguous and
controversial public policy to California's judgment.\206\
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    \204\ Id. While the ZEAS Regulation regulates fleet operators of
airport shuttles, EPA acknowledges that the emission levels
expressed in the ZEAS Regulation are emission standards preempted
under section 209(a) and require a waiver of preemption under
209(b). See Engine Manuf. Ass'n v South Coast Air Quality Mgmt.
Dist., 541 U.S. 246, 255 (2004). Although the ZEAS Regulation does
not expressly require operators to purchase cleaner new vehicles
because regulated parties may comply by converting existing internal
combustion vehicles to zero-emissions vehicles, EPA nevertheless
believes it necessary to evaluate the purchasing requirements and
options within the ZEAS Regulation and waives preemption of the ZEAS
Regulation by this action.
    \205\ See, e.g., Ford Motor, 606 F.2d 1293, 1302 (D.C. Cir.
1979) (``There is no indication in either the statute or the
legislative history that Congress intended to permit the
Administrator to supplant its emission control regulations with
those of California, no matter how sagacious and beneficial the
latter may be. Nor is there any evidence that the Administrator is
supposed to determine whether California's standards are in fact
sagacious and beneficial.''). To the extent comments suggest that
consistency with 202(a) requirements includes limits on the types of
emission standards that may be adopted, these claims do not pertain
to the third prong analysis. Rather, the consistency with section
202(a) requirement relates to the technological feasibility of
California's standards as explained in this decision. Further, the
Administrator has long explained that ``questions concerning the
effectiveness of the available technology are also within the
category outside my permissible scope of inquiry,'' under section
209(b)(1)(C). 41 FR 44209, 44210 (October 7, 1976); 47 FR 7306, 7310
(February 18, 1982) (``I am not empowered under the Act to consider
the effectiveness of California's regulations, since Congress
intended that California should be the judge of `the best means to
protect the health of its citizens and the public welfare.'''
(Internal citations omitted)). Finally, one commenter (AFPM at 12-
13) specifically suggests that consistency with section 202(a),
including section 202(a)(3)(A), means California cannot require
particular technologies. However, as we explain below, section
202(a)(3)(A) does not apply to California and EPA evaluates the
third waiver prong under the technological feasibility, lead time,
and costs requirements in section 202(a)(2). Further, with respect
to CARB's ability to set particular technology requirements, see 71
FR 78190 (December 28, 2006) and Decision Document at EPA-HQ-OAR-
2004-0437-0173, at 35-46).
    \206\ 40 FR 213101, 23103 (May 28, 1975).
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    Therefore, based on the record before us, EPA cannot find that the
opponents of the ACT, ZEAS, and ZEP Certification Regulations waiver
request have met their requisite burden of proof to demonstrate that
such requirements are inconsistent with section 202(a) under EPA's
historical approach to the third waiver criterion.\207\ Thus, EPA
cannot deny CARB's ACT, ZEAS, and ZEP Certification Regulations waiver
request on this basis.\208\
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    \207\ EPA recognizes that CARB may make different policy choices
based on the air quality and other conditions within the State, and
that EPA does not play the role of second-guessing such choices. It
also follows that, in response to the ACT Regulation, a manufacturer
will determine which product offerings to make available in the
California marketplace during the transition to and for showing
compliance with the new standards. These market choices could
include offering for sale a limited set of products. Given the
statutory scheme, the EPA Administrator is to give very substantial
deference to California's judgments. See also International
Harvester v. Ruckelshaus, 478 F 2d. 615, 640 (D.C. Cir. 1979) (``We
are inclined to agree with the Administrator that as long as
feasible technology permits the demand for new passenger automobiles
to be generally met, the basic requirements of the Act would be
satisfied, even though this might occasion fewer models and a more
limited choice of engine types. The driving preferences of hot
rodders are not to outweigh the goal of a clean environment.'').
    \208\ EPA evaluates the lead time associated with CARB's
regulation by examining the date of CARB's adoption of the
regulation and when manufacturers are required to meet the
regulation. The CARB Board adopted the ACT Regulation on June 25,
2020. EPA is guided both by the amount of lead time provided and by
the principles set forth in cases such as International Harvester
and NRDC. The lead time here is between the CARB Board's adoption of
the ACT Regulation in June 2020 and the compliance implementation
for the 2024 model year (recognizing that manufacturers may choose
to certify earlier in 2023 for the 2024 model year). EPA finds no
evidence in the record that manufacturers are unable to comply with
CARB's requirements that commence with the 2024 model year.
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5. The Inapplicability of Section 202(a)(3)(C) to the Third Prong
    Certain commenters asserted that, even if the standards are
technologically feasible, EPA should nonetheless deny the waiver based
on the lead time and stability requirements found in section
202(a)(3)(C).\209\ These commenters claim that because the third waiver
criterion requires California's standards to be ``consistent with''
section 202(a), California must necessarily comply with section
202(a)(3)(C), as that is a sub-provision of 202(a). This argument is
inconsistent with the plain text of the statute. The statutory phrase
``consistent with'' indicates that California's standards should be
congruent and compatible with section 202(a), which in turn sets forth
requirements for Federal standard-setting. The statute does not,
however, obligate California to comply with every single provision of
section 202(a). Not only would doing so make little sense given
Congress' intent to set up two motor vehicle programs in title II--with
California's program dedicated to address the state's air quality
problems and serve as a testing ground for motor vehicle emissions
policy designs and technologies--but it would also conflict with the
text and intent of the waiver provisions in section 209.
---------------------------------------------------------------------------

    \209\ Formerly contained in section 202(a)(3)(B), the 1990
Amendment renumbered this section as section 202(a)(3)(C).

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

    The commenters' argument regarding section 202(a)(3)(C) fails. That
provision, which requires at least four years of lead time and three
years of stability, is a companion to a specific Federal standard-
setting mandate, section 202(a)(3)(A). That mandate is for EPA to
promulgate certain heavy-duty standards for hydrocarbons, carbon
monoxide, oxides of nitrogen, and particulate matter that reflect the
``greatest degree of emission reduction achievable'' using technology
that EPA determines will be available for a given model year, giving
appropriate consideration to cost, energy, and safety factors
associated with application of those technologies. In conjunction with
this directive to set standards reflecting the ``greatest degree of
emission reduction achievable,'' section 202(a)(3)(C) requires EPA to
provide the four years of lead time and three years of stability for
the Federal standards.
    The statute is also explicit that California, by contrast, may
adopt state standards that are ``in the aggregate'' at least as
protective as the Federal standards--a starkly different structure than
requiring each of the relevant heavy-duty standards to reflect the
``greatest degree of emission reduction achievable.'' As such, the
requirement for EPA to find, in granting a waiver, that California's
standards ``are not [in]consistent with'' section 202(a) cannot mean
that California's standards comply with every provision of section
202(a). Further, given that California's standards are not subject to
the ``greatest degree of emission reduction achievable'' mandate, and
apply only in a limited market, it would make little sense in the
statutory scheme to obligate California to comply with the companion
lead time provision in section 202(a)(3)(C) to provide four years of
lead time and three years of stability.
    This plain text reading is well-supported by the history and
purpose of the Act and is also consistent with administrative and
judicial precedents. Commenters rely heavily on EPA's single cursory
and contrary decision in a 1994 MDV waiver, even though by 2012 EPA had
indicated that it did not believe section 202(a)(3)(C) applied to
California's heavy-duty engines and vehicle standards.\210\ We
acknowledge that the 1994 waiver action took a different position on
this issue than we do today. EPA believes that the interpretation of
the ``consistency with section 202(a)'' language that EPA has
historically applied--both before and after the 1994 waiver--is
permissible and is the best view based on all the relevant factors.
EPA's reasoning in the 1994 MDV waiver is unpersuasive, as explained
below, especially because this aspect of the 1994 MDV waiver is
inconsistent with both prior and subsequent agency decisions,\211\ and
more importantly, it is inconsistent with the plain text of the
statute. EPA is therefore taking a different approach from the 1994 MDV
waiver.\212\ Additionally, commenters also mistakenly rely on the D.C.
Circuit's opinion in American Motors Corp. v. Blum, 603 F.2d 978 (D.C.
Cir. 1979) (Blum). Blum addressed a different provision of the CAA and
is readily distinguishable from the instant waivers.
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    \210\ 77 FR 9239 (February 16, 2012).
    \211\ See 77 FR 9239, 9249 (2012); 46 FR 22302, 22304 (1981).
    \212\ FCC v. Fox Television Stations, Inc., 556 U.S. 502 (2009).
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a. EPA's Historical Practice Is Supported by the Text, Context, and
Purpose of the Statute
    We begin by interpreting the text of section 209(b)(1)(C), which
requires EPA to assess whether CARB's standards are ``consistent with
section [202(a)].'' The mere fact that Congress placed a provision
applicable to Federal standards in section 202(a) does not mean
California must comply with it in order for its standards to be
``consistent'' with section 202(a).\213\ Rather, what the ``consistent
with'' provision requires must ``account for the broader context of the
statute as a whole'' \214\ and should be based on analysis of the text,
context, purpose, and history of the relevant portions of the Act. The
term ``consistent'' means ``marked by harmony, regularity, or steady
continuity: free from variation or contradiction,'' ``marked by
agreement,'' and ``showing steady conformity to character, profession,
belief, or custom.'' \215\ These definitions support the conclusion
that the phrase ``consistent with section 202(a)'' does not require
California's standards to comply with all sub-provisions in section
202(a), but rather calls for congruence and compatibility. Caselaw from
the D.C. Circuit explaining the meaning of the phrase ``consistent
with'' in other parts of the Clean Air Act also supports this
understanding that the phrase does not mean lockstep
correspondence.\216\
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    \213\ The D.C. Circuit has noted ``section 202's pervasive
regulation of national motor vehicle emission standards'' and
explained that if the entire provision were applicable to California
``[the Administrator] would be powerless to consider waiving federal
preemption for California's emission standards and certification
process. This lack of power would render the waiver provision and
indeed, the express preemption provision mere surplusage.'' MEMA I,
627 F.2d at 1122.
    \214\ Wisconsin v. EPA, 938 F.3d 303, 316 (D.C. Cir. 2019) (``We
note that we do not conclude that the phrase `consistent with' in
the Good Neighbor Provision necessarily effects an incorporation of
the full contours of every provision of Title I in pure, lockstep
fashion. As we have observed elsewhere in construing the same words
in the context of the same statute, the phrase `consistent with'
other statutory sections `calls for congruence or compatibility with
those sections, not lock-step correspondence.''') (Citing Envtl.
Def. Fund Inc. v. EPA, 82 F.3d 451, 460 (D.C. Cir. 1996); Nuclear
Energy Institute, Inc. v. EPA, 373 F.3d 1251, 1270 (D.C. Cir.
2004)).
    \215\ Consistent, https://www.merriam-webster.com/dictionary/consistent (last accessed Jan. 30, 2023).
    \216\ See Wisconsin v. EPA, 938 F.3d 303, 316 (D.C. Cir. 2019)
(collecting authorities).
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    EPA thus believes that the phase ``consistent with'' does not
require California's standards to strictly conform or comply with every
provision in section 202(a). After all, that would defeat the scheme
Congress set up to encourage two sets of standards--the Federal
standards and California's standards. Congress chose the term
``consistent with'' instead of, for example, ``comply with,'' or terms
connoting identicality such as ``the same as,'' or ``identical to'' in
section 209(b)(1)(C).\217\ The use of ``consistent with'' in section
209, rather than ``identical'' or the like, makes perfect sense because
Congress established two programs for control of emissions from new
motor vehicles in Title II--EPA emission standards adopted under the
Act and California emission standards adopted under its state law.
Motor vehicles are ``either `federal cars' designed to meet the EPA's
standards or `California cars' designed to meet California's
standards.'' \218\ Thus, an interpretation that every portion of
section 202(a) must be applicable to California standards would defeat
Congress's plan.\219\ In contrast, EPA's

historical practice regarding ``consistent with'' is in accordance with
both Congress's structure and the case law that guides how the phrase
should be interpreted by ensuring that California, in setting its
standards, evaluates the same factors that EPA does--e.g., feasibility,
lead time, and cost. EPA also ensures that enforcement mechanisms, such
as test procedures, are compatible to avoid creating challenges for
automakers in complying with both California and federal
standards.\220\ For example, EPA has considered California's
classification scheme for heavy-duty vehicles as consistent with
section 202(a), even though it is not identical to the federal
classification.\221\ This understanding of ``consistent with'' is
supported by case law, such as MEMA II: ``Section 209(b)(1) makes clear
that section 202(a) does not require, through its cross-referencing,
consistency with each federal requirement in the act. . . .
California's consistency [with section 202(a)] is to be evaluated `in
the aggregate,' rather than on a one-to-one basis. CAA section
209(b)(1).'' \222\ In sum, section 209(b)(1)(C) does not require
California to conform identically to every provision of section 202(a).
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    \217\ EPA notes, moreover, that elsewhere in the statute
Congress did use the term ``identical,'' indicating that Congress
knew how to clearly express when it wanted identicality as opposed
to consistency. For example, under section 177, Congress ``permitted
other states to `piggyback' onto California's standards, if the
state's standards `are identical to the California standards for
which a waiver has been granted for such model year.''' Motor
Vehicle Mfrs. Ass'n v. New York State Dep't of Envtl. Conservation,
17 F.3d 521, 525 (2d Cir. 1994) (Emphasis added); Similarly, in
section 211(c)(4)(A)(ii), state fuel controls that are ``identical''
to controls promulgated under section 211(c)(1) are otherwise not
preempted. (Emphasis added). Section 211(c)(4)(A)(ii)(Emphasis
added).
    \218\ Engine Mfrs. Ass'n v. EPA, 88 F.3d 1075, 1079-80, 1088
(D.C. Cir. 1996).
    \219\ For example, the requirement in section 202(a)(3)(D) for
the Administrator to conduct a study for the practice of rebuilding
heavy-duty engines and, on the basis on such study, consider
prescribing requirements for rebuilding practices is clearly
directed at EPA and not a requirement of California. It would not be
a reasonable reading of section 209(b)(1)(C) to require California
to complete an identical study in order to be ``consistent with''
section 202(a).
    \220\ 42 FR 2337, 2338 (January 11, 1977).
    \221\ Id. (A medium duty vehicle is defined by the CARB as a
subset of the heavy-duty vehicle class, and is any motor vehicle
(except a passenger car) with a gross vehicle weight rating (GVWR)
of between 6000 and 8500 pounds).); See also, 43 FR 1829, n.2, 1830,
n.9 (January 12, 1978); CARB Waiver Request at 3 n.6; 78 FR 2114 n.9
(Medium-duty vehicles (MDVs) are vehicles in California's
regulations between 8,500 and 114,000 lbs GVWR that are also called
Class 2b/Class 3 vehicles. These vehicles are generally termed
heavy-duty vehicles under EPA's regulation).
    \222\ MEMA II, 143 F.3d 449, 463-64.
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    Having established that California's standards do not need to be
identical to or meet all of the requirements set out in section 202(a)
for Federal standards, we now turn to the question whether California's
standards must comply with section 202(a)(3)(C)'s requirements to be
``consistent'' with section 202(a). To answer this question, EPA
further examines the statute's text and purpose. Based on the plain
language, statutory context and legislative history, we conclude that
the best view is that compliance with section 202(a)(3)(C) is not
necessary for consistency. In particular, section 202(a)(3)(C) is a
companion lead time provision that applies to Federal standard-setting
under section 202(a)(3)(A) and is therefore not relevant to
California's program.
    In general, section 202(a)(3), which was first added in the 1977
Amendments, reflected congressional frustration at EPA's slow pace of
regulating emissions from heavy-duty vehicles and engines and was thus
a direct command to EPA.\223\ By its terms, section 202(a)(3)(A)(i)
directs EPA to establish standards for hydrocarbons, carbon monoxide,
oxides of nitrogen, and particulate matter emissions from heavy-duty
vehicles and engines that ``reflect the greatest degree of emission
reduction achievable.'' \224\ Section 202(a)(3)(C) in turn requires
that such stringent standards (``those promulgated . . . under this
paragraph,'' section 202(a)(3)(C)) have at least four years of lead
time and apply for no less than three model years.\225\ Congress
intended the fixed lead time and stability provisions of section
202(a)(3)(C) as a companion to the requirement in section 202(a)(3)(A)
to promulgate national standards which ``reflect the greatest degree of
emission reduction achievable,'' balancing the mandate for the most
stringent possible standards with granting regulated manufacturers a
minimum amount of lead time and considering costs and other
factors.\226\ Congress chose these prescribed lead time and stability
requirements because of industry concerns over the level of stringency
expected of EPA's national standards. According to the D.C. Circuit
``[t]hat requirement was enacted for the benefit of manufacturers to
allow time for them to design and develop engines in compliance with
newly promulgated standards.'' \227\ Both the four-year lead time and
the three-year stability time frames thus provide assurance to the
heavy-duty industry of a minimum amount of lead time and stability to
meet EPA's national standards considering the mandate to EPA to
promulgate standards which reflect the greatest degree of emission
reduction achievable under in section 202(a)(3)(A).\228\ (``It seems
that Congress intended the EPA in promulgating standards with an
adequate lead period to engage in reasonable predictions and
projections in order to force technology.'').\229\
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    \223\ NRDC v. Thomas, 805 F.2d 410 (D.C. Cir. 1986) (for the
history and treatment of the 1977 Amendments for heavy-duty vehicles
and engines particulate matter, oxides of nitrogen, carbon monoxide
and hydrocarbons standards). Acting under the 1977 Amendments, EPA
first promulgated heavy-duty vehicle and engines standards on May
15, 1985 (50 FR 10606) but by that time California had been granted
waivers for heavy-duty vehicles and engines standards (See for
example, 34 FR 7348 (May 6, 1969); 36 FR 8172 (April 30, 1971); 40
FR 23102 (May 28, 1975); Section 202(a)(3)(A)(iii) was originally
contained in the 1977 Senate bill ``applicable to emissions of
carbon monoxide, hydrocarbons, particulates, and oxides of nitrogen
from heavy duty trucks, buses, and motorcycles and engines
thereof.'' S. Rep. No. 252, 95th Cong., 1st Sess. at 19 (1977). See
S. Rep. No.127, 95th Cong., 1st Sess. 193 (1977), reprinted in 3
Legislative History 1567. The 1977 Amendments added section
202(a)(3) directing EPA to set heavy-duty vehicle emission standards
for certain emissions for the 1983 model year and later. (Congress
having identified a need for standards in 1970 ``had become
impatient with the EPA's failure to promulgate a particulate
standard'' for heavy duty vehicles.'' NRDC, 655 F.2d at 325 (citing
S. Rep. No.127, 95th Cong., 1st Sess. 67 (1977), reprinted in 3
Legislative History 1441). This language appears in the same
legislative history where Congress expressed approval for EPA's
implementation of the waiver provision over the past decade and
expanded California's discretion to adopt standards that were
intended to address the state's severe air quality issues.
    \224\ NRDC v. Thomas, 805 F.2d at 414-16.
    \225\ Formerly contained in section 202(a)(3)(B), the 1990
Amendments renumbered this section as section 202(a)(3)(C) and
slightly modified its terms while still retaining the four-year lead
time and three-year stability requirement and extending this lead
time to standards promulgated by EPA for the control of
NOX emissions from heavy-duty vehicles and engines.
(``Any standard promulgated or revised under this paragraph and
applicable to classes or categories of heavy-duty vehicles or
engines shall apply for a period of no less than 3 model years
beginning no earlier than the model year commencing 4 years after
such revised standard is promulgated.'' Section 202(a)(3)(C)).
    \226\ NRDC v. Thomas, 805 F.2d 420-23 (Rejecting argument that
the terms ``maximum'' and ``greatest'' before the phrase ``degree of
emission reduction'' meant that EPA must set standards at the
performance level of the best vehicle or engine and upholding
instead EPA's consideration and balancing of all relevant factors in
setting applicable standards.).
    \227\ EPA ``cannot cite us to any precedent allowing a court to
ignore an explicit leadtime requirement.'' NRDC v. Thomas, 805 F.2d
at 435 (Reversing EPA's decision to provide less than the
statutorily mandated four-year lead time for certain model year
heavy-duty vehicles and engines standards.). See also, 805 F.2d 435
n.40.
    \228\ ``[I]n adding section 202(a)(3)(A)(iii) . . . Congress
directed the EPA to give priority to establishing particulate
emission standards for heavy-duty vehicles and left the agency free
to exercise its power under section 202(a)(1) to regulate light-duty
automobiles, whether diesel-powered or otherwise.'' NRDC., at 326;
H.R. Conf. Rep. No. 294, 95th Cong., 1st Sess. 542-43 (1977)
(``Additional revisions of up to 3 years each could be granted at
three-year intervals thereafter;'' and Congress ``provides four
years lead time before temporary or permanent revision of any
statutory standard.'').
    \229\ NRDC v. Thomas, 805 F.2d at 430.
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    Several factors indicate that section 202(a)(3)(C) is a companion
provision to section 202(a)(3)(A). As a general matter, the level of
stringency of a standard and its accompanying lead time are
intertwined. Notably, a standard does not act in isolation, but rather
goes into effect after a certain amount of lead time and in a
particular model year (e.g., a 1 gram/mile standard effective beginning
model year 2027). The feasibility of a standard, including the
availability of technology and its costs, also depends on the lead time
provided. Further, the actual impact of a standard, whether on
regulated entities or its protectiveness of public

health and the environment, depends on the lead time provided.
    The context of the statute also evinces the link between sections
202(a)(3)(A) and (C). EPA's general authority to establish motor
vehicle standards is found in section 202(a)(1), which authorizes the
Administrator to prescribe emission standards for motor vehicles upon
making an endangerment finding but does not specify the stringency of
the standard (i.e., there is no requirement to promulgate standards
that reflect the greatest degree of emission reduction
achievable).\230\ Section 202(a)(1) in turn is accompanied by the
general lead time provision in section 202(a)(2), which does not set
any fixed lead time but rather allows the Administrator to determine
the lead time ``necessary to permit the development and application of
the requisite technology, giving appropriate consideration to the cost
of compliance within such period.'' By contrast, in enacting section
202(a)(3), Congress was more prescriptive in both the appropriate level
of stringency and lead time, requiring both standards that reflect the
greatest degree of emission reduction achievable for specific
pollutants emitted from heavy-duty vehicles and at least four-year lead
time. This contextual contrast between sections 202(a)(1)-(2) and
202(a)(3) further demonstrates the close link between the standard-
setting provision in section 202(a)(3)(A) and the lead time provision
in section 202(a)(3)(C). That is, Congress departed from EPA's general
authority to set motor vehicle emission standards in sections
202(a)(1)-(2) in two respects by making a very specific legislative
compromise in 202(a)(3): (1) By forcing stringent standards that
reflect the greatest degree of emission reduction achievable, while (2)
also expecting that such standards may be sufficiently difficult to
achieve such that manufacturers would be entitled to a minimum of four
years of lead time and three years of stability.\231\ Legislative
history supports this connection.\232\ Opponents of the waiver,
however, contend that California's standards must ``reflect the
greatest degree of emission reduction achievable'' required for Federal
standards in 202(a)(3)(A) and meet the companion lead time and
stability requirements in section 202(a)(3)(C).
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    \230\ And ``[w]hile section 209(b) requires consideration of
whether the adoption of standards by California is consistent with
section 202(a), nevertheless [the Administrator's] discretion in
determining whether to deny the waiver is considerably narrower than
[his] discretion to act or not to act in the context promulgating
Federal standards under section 202(a). . . . [The Administrator]
would therefore feel compelled to approve a California approach to
the regulation of . . . emissions which [he] might choose not to
adopt at the Federal level.'' 41 FR 44210.
    \231\ NRDC v. Thomas, 805 F.2d at 421-24, 430, 435. EPA
acknowledges that the lead time requirements in 202(a)(3)(C) apply
to ``any standard promulgated or revised under this paragraph'' and
that paragraph (3) also includes other standard-setting provisions.
We view these additional provisions as further support for the main
argument in the text: the lead time requirements in 202(a)(3)(C)
accompany specific Federal standard-setting requirements and do not
act in isolation. Thus, those lead time requirements were not
intended to apply to all Federal standards for heavy-duty vehicles
or engines, much less to apply to California standards. See infra
footnote 250. Instead, they apply only to standards ``promulgated or
revised under this paragraph.''
    \232\ H.R. Conf. Rep. No. 564, 95th Cong., 1st Sess. 542-43
(1977) (The conference agreement provides four years lead time
before temporary or permanent revision of any statutory standard and
requires the Administrator to promulgate particulate standards based
on criteria set forth in the House interim standards provision.
These standards are to become effective as expeditiously as
practicable taking into account the lead time necessary to comply,
but in no event later than 1981 model year.). This legislative
history from the Conference Report indicates that section
202(a)(3)(C) provides lead time and stability requirements for
standards promulgated under section 202(a)(3)(A).
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    Congress' direction to EPA in sections 202(a)(3)(A) and (C) stands
in stark contrast to its approach to California's standards. EPA's
practice of providing a highly deferential review of California's
standards in waiver proceedings was already well established by 1977,
and Congress recognized and approved of this practice.\233\ And in the
very same 1977 Amendments, Congress instructed California to consider
the protectiveness of its standards ``in the aggregate,'' rather than
requiring each California standard being as or more stringent than its
Federal counterpart.\234\ Congress explicitly recognized that
California's mix of standards could ``include some less stringent than
the corresponding federal standards.'' \235\ ``[T]here is no question
that Congress deliberately chose in 1977 to expand the waiver provision
so that California could enforce emission control standards which it
determined to be in its own best interest even if those standards were
in some respects less stringent than comparable federal ones.'' \236\
The four-year lead time and three-year stability requirement for heavy-
duty engines and vehicles standards contained in section 202(a)(3)(C)
should thus be properly viewed as applying to EPA's standard-setting
authority under section 202(a)(3)(A), and not California's authority as
applied under the waiver provisions. To give proper effect to the ``in
the aggregate'' language in section 209(b)(1), and for California to
retain its ability to set more stringent standards for some pollutants
and less stringent for others, California is not explicitly required,
nor should it be implicitly required by the cross-reference to section
202(a), to set heavy-duty vehicle emission standards that ``reflect the
greatest degree of emission reduction.'' In other words, the
legislative compromise that Congress established in 202(a)(3) for
Federal standard-setting--between standards that reflect the greatest
degree of emission reduction achievable and at least four years of lead
time and three years of stability--does not make sense in the
California context: since California can establish differing (and
sometimes less stringent) standards than what is required by
202(a)(3)(A), it also follows that it may prescribe differing lead time
and stability requirements than what is required by 202(a)(3)(C))--
provided those requirements are ``consistent with'' EPA's general
approach to addressing feasibility, lead time, and cost pursuant to
section 202(a)(2). The 1977 Amendment to section 209(b)(1) thus also
supports the view that California's standards should be reviewed under
the traditional feasibility test of section 202(a), and that California
need only provide lead time it deems sufficient based on its analysis
of technology feasibility and cost for standards at issue, and that EPA
reviews California's determinations.
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    \233\ In the 1977 Amendments to section 209(b)(1), Congress also
approved EPA's interpretation of the waiver provision as providing
appropriate deference to California's policy goals and consistent
with Congress's intent ``to permit California to proceed with its
own regulatory program'' for new motor vehicle emissions. H.R. Rep.
No. 95-294, at 301 (1977); MEMA I, 627 F.2d at 1120-21 (``The
language of the statute and its legislative history indicate that
California's regulations, and California's determination that they
comply with the statute, when presented to the Administrator are
presumed to satisfy the waiver requirements and that the burden of
proving otherwise is on whoever attacks them.''); Id. at 1110 (``The
Committee amendment is intended to ratify and strengthen the
California waiver provision and to affirm the underlying intent of
that provision, i.e., to afford California the broadest possible
discretion in selecting the best means to protect the health of its
citizens and the public welfare.'' Citing H.R. Rep. No. 294, 95th
Cong., 1st Sess. 30102 (1977), U.S. Code Cong. Admin. News 1977, p.
1380 (emphasis in original).'')
    \234\ ``Congress decided in 1977 to allow California to
promulgate individual standards that are not as stringent as
comparable federal standards, as long as the standards are `in the
aggregate, at least as protective of public health and welfare as
applicable federal standards.'' Ford Motor, 606 F.2d 1293, 1302 (DC
Cir. 1979) (``[T]he 1977 amendments significantly altered the
California waiver provision.'').
    \235\ H.R. Rep. No. 294, 95th Cong., 1st Sess. 302 (1977).
    \236\ MEMA I, 627 F.2d at 1110.
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    As previously noted, the 1977 Amendments removed the stringency
requirements for California standards

under review and now allows for granting waivers if standards are ``in
the aggregate'' as protective of health as federal standards in section
209(b)(1). This amendment reflected California's wish to ``trade off''
controlling carbon monoxide emissions, which were not as critical of a
problem in California, for NOX emissions, which were and
continue to present severe air quality challenges in California.\237\
Therefore, California's carbon monoxide standards can now be less
stringent than federal standards.\238\ Recognizing that both carbon
monoxide and NOX are also listed in section 203(a)(3)(C),
and then reading this section as applicable to California's heavy-duty
vehicles standards, however, would entirely undermine the purpose of
the 1977 Amendments. Under such a reading, if California identified a
need to relax an existing carbon monoxide standard to enable a much
more stringent NOX standard, based on the interactions
between the control technologies involved, it would be precluded from
doing so because the carbon monoxide standard would not meet the
``greatest degree of emission reduction'' requirement. This result is
in direct conflict with Congress amending section 209(b)(1) to enable
California to do precisely that, with precisely those pollutants.\239\
As such, it is not a reasonable reading of the statute.
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    \237\ 58 FR 4166, LEV Waiver Decision Document at 50-51.
    \238\ MEMA II, 142 F.3d at 464 (``EPA has observed, `California
would not be denied a waiver if its CO standard were slightly higher
than the federal . . . standard. . . . This is despite the fact that
section 202(g) contains specific standards for CO that EPA must
promulgate.' EPA Air Docket A-90-28, Doc. No. V-B-1 at 47.'').
    \239\ MEMA II, 142 F.3d at 464 (``California would not be denied
a waiver if its CO standard were slightly higher than the federal .
. . standard. . . . This is despite the fact that section 202(g)
contains specific standards for CO that EPA must promulgate.'');
MEMA I, 627 F.2d at 1110 n.32 (explaining the specific intent of
Congress to allow California carbon monoxide standards to be less
stringent than federal carbon monoxide standards).
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    Moreover, the D.C. Circuit has held that not all the 1977
amendments to the Clean Air Act apply in the waiver context. In MEMA I,
for instance, the Court held that section 302 was inapplicable to
section 209 because ``[s]ection 302(k)'s definition [of standards] was
not enacted until ten years after the original waiver provision, and it
was developed in the context of regulating emissions from stationary
sources.'' \240\ Similarly, Congress developed section 202(a)(3) in the
context of the nationwide regulation of emissions from heavy-duty
engines and vehicles by EPA, a decade after enactment of the original
waiver provision and also after California had been regulating heavy-
duty engine emissions with the appropriate waivers that EPA granted
applying the traditional consistency test.\241\ In amending section
202(a) to ensure more effective Federal regulation of certain heavy-
duty vehicle emissions, Congress gave no indication that it had any
intention of upending the application of the traditional consistency
test to California standards.
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    \240\ MEMA I, 627 F.2d 1095, 1112 n.35 (DC Cir. 1979) (``For
this reason we find unpersuasive petitioners' suggestion that
section 302(k) of the Clean Air Act, 42 U.S.C. 7602(k) (Supp. I
1977), which contains a definition of ``emission standards,''
controls our examination of the meaning of the word ``standards'' in
section 209); Motor Vehicle Mfrs. Ass'n v. New York State Dep't of
Envtl. Conservation, 17 F.3d 521, 533 (2d Cir. 1994).
    \241\ ``The 1977 Amendment also drew heavily on the California
experience in the ten years since enactment of the first waiver
provision. See 123 Cong. Rec. H4852 (daily ed. May 21, 1977); id. at
H5061 (daily ed. May 25, 1977).'' MEMA I, 627 F. 2d. 1095, 1111
n.34; For example, EPA granted a waiver for 1972 and later heavy-
duty vehicles gasoline standards to California on May 6, 1969 (34 FR
7348). In turn, EPA first promulgated heavy-duty vehicle and engine
standards pursuant to the 1977 Amendments in 1985. 50 FR 10606 (May
15, 1985).
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    Further, as far back as 1967 Congress in enacting section 209(b)
recognized that emissions technology would be introduced and tested
first in California before nationwide introduction and use.\242\
According to the D.C. Circuit: ``The history of congressional
consideration of the California waiver provision, from its original
enactment up through 1977, indicates that Congress intended the State
to continue and expand its pioneering efforts at adopting and enforcing
motor vehicle emission standards different from and in large measure
more advanced than the corresponding Federal program; in short, to act
as a kind of laboratory for innovation.'' \243\ EPA has thus also long
recognized Congressional intention that California ``pioneer''
emissions control.\244\ EPA's view is supported by legislative history.
Congress recognized California's severe air quality problems and
envisioned California's role as an innovative laboratory for motor
vehicle emission standards and control technology. California's
``unique [air pollution] problems and [its] pioneering efforts
justif[ied] a waiver of the preemption section;'' California ``should
serve the Nation as a `testing area' for more protective standards.''
\245\ Similarly, California is to ``blaze its own trail with a minimum
of federal oversight.'' \246\ EPA has thus ``[h]istorically granted
waivers allowing the introduction of new technology in California prior
to its introduction nationwide'' intending for the phase-in of new
control technology in California as a means of successful
implementation nationwide.\247\ The Administrator has explained that
allowing California to first introduce technology ``best serves the
total public interest and the mandate of the statute. It promotes
continued momentum toward installation of control systems meeting the
statutory standards while minimizing risks incident to national
introduction of new technology.'' \248\ Applying fixed lead time and
stability requirements to the California heavy-duty vehicle program
would thwart California's ability to serve as a laboratory of vehicle
emission reduction technologies and delay the transfer of

those innovations to the country as a whole under federal standards.
Given Congress's desire for California to serve as a laboratory for
innovation, the traditional feasibility inquiry under section
209(b)(1)(C) suffices to ensure that manufacturers have sufficient time
to deploy technologies to comply within the California market while
allowing California to move faster in deploying feasible technologies
than the fixed lead time and stability requirements would allow.
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