ozone NAAQS. Absent data or public comments indicating that the
previous RACT determination is no longer appropriate, the state need
not adopt additional SIP controls to meet the new RACT requirement for
these sources. In such cases, the state's SIP revision submitted after
notice and comment should contain a certification, with appropriate
supporting information (including consideration of new data),
indicating that these sources are already subject to SIP-approved
requirements that still meet the RACT obligation. There are cases where
the initial RACT analysis under the 1-hour standard or the 1997
standard for a specific source or source category concluded that no
additional controls were necessary. In such cases, a new RACT
determination is needed to consider whether more cost effective control
measures have become available for sources that were not previously
regulated. A re-analysis may determine that controls are now
economically and technically feasible and are necessary to meet the
RACT requirement. Please refer to the Response to Comments document for
additional detail on this topic.
    Comment: A commenter expressed the concern that a nonattainment
area-wide weighted NOX averaging demonstration would exempt
EGUs used primarily on high electricity demand days from NOX
control. The commenter also expressed that the exemption of HEDD EGUs
from NOX control does not reduce NOX emissions
when and where such reductions are necessary to attain the ozone NAAQS.
Another commenter asserted that the EPA's definition of RACT plainly
requires each individual source to apply control technology to achieve
the lowest emission limitation that each particular source is capable
of meeting considering technology and economic feasibility. The
commenter argued that substitution of area-wide averaging for source-
specific RACT does not meet the language of section 182(b)(2) of the
Act, which requires SIPs for Moderate and above areas to require
implementation of RACT ``with respect to . . . [a]ll VOC sources in the
area covered by any CTG issued before November 15, 1990,'' and ``[a]ll
other major stationary sources of VOCs that are located in the area.''
42 U.S.C. 7511a(b)(2). The commenter argued that the EPA is supplanting
these statutory directives with an area-wide averaging program that
allows some sources to avoid installing RACT controls.
    Response: The EPA's existing policy recognizes that states can meet
NOX RACT requirements by submitting as part of their
NOX RACT SIP submittal a demonstration that the weighted
average NOX emission rate from sources in the nonattainment
area subject to RACT achieves RACT-level reductions. We note, however,
that this policy does not include an exemption for HEDD EGUs from
NOX control.
    Additionally, the EPA disagrees with the comment that ``area-wide
averaging is not a legally permissible method for complying with'' RACT
and that RACT requires reductions from ``each and every source'' in an
area. The EPA believes that the statute, as interpreted by the court in
NRDC v. EPA, provides a state with the option of demonstrating that its
program achieves RACT level reductions by showing emission reductions
greater than or equal to reductions that would be achieved through a
source-specific application of RACT in the nonattainment area. NRDC v.
EPA interprets the CAA as requiring that each nonattainment area must
achieve ``RACT-level reductions,'' which is to say the reductions that
would be achieved ``if RACT-level controls were installed in the
area.'' 571 F.3d at 1258. In sum, nothing in the CAA or in NRDC v. EPA
requires that ``each and every'' source in the area employ RACT or
achieve RACT-level reductions. Consistent with previous guidance, the
EPA continues to believe that RACT can be met on average by a group of
sources within a nonattainment area rather than at each individual
source. Therefore, states can show that SIP provisions for these
sources meet

the ozone RACT requirement using the averaging approach.
    Comment: Several commenters expressed general support for the
proposed policy that would allow states to demonstrate that compliance
with a regional trading program by affected sources within a
nonattainment area will satisfy RACT requirements for those sources.
Several commenters additionally expressed that it may be appropriate
for states to rely on a cap-and-trade program that is limited to a
nonattainment area for purposes of meeting RACT for sources located in
the nonattainment area.
    Other commenters did not support the proposed approach. A few of
these commenters expressed concerns that by providing states with an
option to rely on trading programs, the EPA is allowing for sources to
turn off their controls in upwind states. Commenters additionally
suggested that RACT should apply on an individual basis to every
affected stationary source in a nonattainment area. Commenters implied
that the EPA should specifically require controls to be operational at
all times at these sources.
    Response: The EPA appreciates, and generally agrees with, the
supporting comments pertaining to the proposed policy allowing states
to rely on a regional cap-and-trade program to comply with RACT if they
provide an appropriate technical demonstration. The EPA also agrees
that states may rely on a cap-and-trade program that is limited to a
nonattainment area for purposes of meeting RACT for sources located in
the nonattainment area. The EPA disagrees, however, with those
commenters that say that states should not have the option to
demonstrate that compliance with a regional trading program by sources
in a nonattainment area achieves RACT-level reductions within the
nonattainment area. In NRDC v. EPA, the Court noted that a
determination that RACT was satisfied by compliance with a regional
trading program might be permissible for an area if accompanied by a
technical analysis demonstrating that the program in fact ``results in
greater emissions reductions in a nonattainment area than would be
achieved if RACT-level controls were installed in that area.'' \35\ In
other words, the Court rejected the notion that a regional trading
program intended to eliminate interstate transport of emissions
consistent with CAA section 110(a)(2)(D)(i) could automatically
constitute the RACT-level of control required by CAA section 172(c)(1),
but held open the possibility that an analysis could be conducted to
determine whether such a program would result in the same, or higher
level of emissions reductions in individual nonattainment areas.
---------------------------------------------------------------------------

    \35\ 571 F.3d at 1258.
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    The EPA additionally disagrees with any implication by the
commenters that the proposal should address whether controls are
required to be operational at all times at sources in the nonattainment
area. The EPA's NOX RACT guidance (Nitrogen Oxides
Supplement to the General Preamble, 57 FR 55625; November 25, 1992)
includes a policy where states may develop RACT programs that are based
on ``area wide average emission rates.'' Additional guidance on area-
wide RACT provisions is provided by the EPA's January 2001 economic
incentive program guidance titled, ``Improving Air Quality with
Economic Incentive Programs.'' Thus, the EPA's existing policy
recognizes that states may demonstrate as part of their NOX
RACT SIP submittal that the weighted average NOX emission
rate from a group of sources in the nonattainment area subject to RACT
meets NOX RACT requirements.
    Comment: The EPA received several supporting and opposing comments
regarding whether the EPA should modify the RACT guidance to allow for
states to consider the ozone air quality benefits of reductions in VOC
emissions for purposes of RACT determinations. Supporting comments
provided examples where photochemical modeling appears to show that in
some areas VOC reductions have a limited effect on reductions in ozone
concentrations. These commenters also provided information that may be
useful in evaluating the potential definition of ``negligible effect.''
Several commenters also provided potential legal justifications for
modifying the RACT guidance in this respect.
    Response: The EPA recognizes that modification of the existing
guidance on determining RACT could add flexibility that would be
beneficial to the efficiency of ozone controls in some states. In
addition, it appears that there is available science suggesting that
ozone formation in some areas is NOX-limited, such that
changes in anthropogenic VOC emissions will have little effect on ozone
concentrations. However, the EPA does not believe that the legal
arguments provided by the commenters are sufficient to address
potential statutory restrictions. The main legal argument presented by
commenters in support of flexibility is that the EPA has ``discretion''
to determine what constitutes ``reasonably'' available control
technology. However, the EPA may not have sufficient discretion to
support this modification of the existing RACT guidance. CAA section
182(b)(2) provides that SIPs must ``require the implementation of
reasonably available control technology'' with respect to ``VOC
sources.'' It does not clearly authorize consideration of whether
technology that is ``reasonably available'' is also reasonably
effective with respect to improving air quality or reducing ozone
formation, and it does not specify criteria for discerning a level of
air quality improvement below which available technology does not need
to be implemented.
    Comment: Some opposing comments raised equity concerns with
modifying the RACT guidance, while other comments raised legal
concerns. Several commenters stated the EPA has issued NOX
waivers in the past under CAA section 182(f) and the proposed approach
would appear to establish a VOC waiver scheme, which the commenters do
not support and is not expressly provided by the statute. Several
commenters stated that the CAA requires RACT on all major sources of
VOC in nonattainment areas and the commenters do not believe that the
EPA has the authority to eliminate this requirement. One commenter also
stated that not only has Congress made clear that CAA section
182(b)(2)'s mandates for VOC RACT are not limited by any sort of air
quality benefit test, but the plain meaning of ``economic feasibility''
does not have anything to do with air quality benefits, citing several
cases.
    Response: Given these concerns about whether the CAA authorizes
such an approach, and as is discussed above, the EPA is not at this
time revising our long-standing RACT determination guidance. However,
the EPA may continue to explore this option and potential legal support
for it in the future.
    Comment: The EPA received one supporting comment regarding the
proposed approach that for VOC sources subject to MACT standards,
states would be allowed to streamline their RACT analysis by including
a discussion of the MACT controls and considerations relevant to VOC
RACT. The EPA received one additional comment suggesting that, before
requiring states to apply NOX RACT to all combustion
sources, the EPA should study certain MACT rules and specifically
recommend the SIP credit for federal MACT measures in SIP planning.
    Response: The EPA thanks the commenter for their support. Regarding
the issue of whether to specifically recommend the SIP credit for
federal

MACT measures in SIP planning, the EPA is not planning at this time to
develop specific recommendations for SIP credit for Federal MACT
measures. Additionally, the commenter seems to imply that the EPA
should not require compliance with RACT until such a study is
completed. The EPA disagrees with the commenter. Regardless of whether
or not the EPA conducts such a study, the RACT requirements remain
requirements that must be met under the CAA, whether through reliance
on MACT or otherwise.
    Comment: One commenter expressed concern that the EPA's proposed
requirement to have RACT in place by January 1, 2017, may not provide
enough time for implementation. The commenter noted that if the EPA
needs to develop additional CTGs for the current ozone NAAQS, states
may not have ample time to develop regulations that provide sufficient
time for sources to implement RACT for sources covered by additional
CTGs.
    Response: The EPA disagrees with the commenter that a requirement
for RACT to be in place by January 1, 2017, for areas designated
nonattainment effective July 20, 2012, (and all areas of the OTR), does
not allow enough time for implementation. The EPA believes that the
January 1, 2017, date allows a sufficient amount of time for states to
make RACT determinations and for sources to meet RACT requirements on
the time-table originally anticipated under the 1990 CAA Amendments,
and ensures that RACT measures are required to be in place throughout
the last ozone season prior to the Moderate area attainment date of
July 20, 2018.
    Given the comment received, we wish to provide further
clarification regarding the RACT implementation deadline. The EPA notes
that the requirement to develop a RACT SIP applies only to
nonattainment areas that are classified as Moderate or above (i.e.,
Serious, Severe, or Extreme). Therefore, for such areas that were
designated effective July 20, 2012, RACT SIPs are due within 2 years of
the effective date of designation, by July 20, 2014. Sources subject to
RACT in those areas would then need to implement RACT by January 1,
2017.\36\ If an area is reclassified from Marginal to Moderate at some
later date, then that area would become subject to a new RACT
requirement, and the EPA would set new SIP submission and RACT
compliance dates on a reasonable schedule that the Administrator will
establish in the applicable notice and comment rulemaking reclassifying
the area. For areas newly redesignated to nonattainment, the RACT SIP
is due 2 years from the effective date of designation, and the
implementation deadline is January 1st of the 5th year after the
effective date of designation.
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    \36\ We note that the RACT compliance date does not change
relative to the RACT SIP submission. This compliance date is fixed,
such that if a state submits a RACT SIP past the deadline, then
sources would still have to comply with the RACT requirements by
January 1, 2017.
---------------------------------------------------------------------------

    Additionally, the January 1, 2017, RACT implementation deadline,
would not automatically apply to sources covered by future CTGs. If a
new CTG is developed, all current Moderate or above areas would be
required to revise their SIPs for the sources covered by the CTG within
the period set forth by the EPA in issuing the CTG document (see
section 182(b)(2) of the CAA), which would occur through notice and
comment rulemaking. This will give sources lead time to comply with the
new requirement.
    Comment: With regard to the EPA's proposed requirement to have RACT
in place by January 1, 2017, one commenter asserted that it was not
Congress's intention to require another round of RACT revisions in the
short period of time between ozone NAAQS revisions. The commenter
claims the short period of time would not allow a facility to recoup
the investment in the original pollution control before the requirement
to reconsider if the next round RACT determinations requires newer
controls. The commenter also believes that it would be burdensome for
states to adopt new RACT SIPs and resubmit them for EPA approval.
    Response: The EPA disagrees with the commenter that Congress did
not realize the implication that the 5-year NAAQS review cycle would
potentially require new RACT determinations each time a NAAQS is
revised. The EPA has offered flexibilities in applying the RACT
requirements for areas that have previously met requirements for the 1-
hour or the 1997 8-hour ozone NAAQS.
2. Reasonably Available Control Measures (RACM)
a. Summary of the Proposal
    The EPA proposed to continue to apply to the 2008 ozone NAAQS,
existing RACM guidance that interprets the RACM provision to require a
demonstration that the state has adopted all reasonable measures
(including RACT) to meet RFP requirements and to demonstrate attainment
as expeditiously as practicable and thus that no additional measures
that are reasonably available will advance the attainment date or
contribute to RFP for the area.37 38 39 The EPA also
proposed that although states should consider all available measures,
including those being implemented in other areas, a state must adopt
measures for an area only if those measures are economically and
technologically feasible and will advance the attainment date or are
necessary for RFP.
---------------------------------------------------------------------------

    \37\ ``State Implementation Plans; General Preamble for Proposed
Rulemaking on Approval of Plan Revisions for Nonattainment Areas''
44 FR 20372 at 20375 (April 4, 1979). ``State Implementation Plans;
General Preamble for the Implementation of Title I of the Clean Air
Act Amendments of 1990; Proposed Rule.'' 57 FR 13498 at 13560 (April
16, 1992).
    \38\ ``Guidance on the Reasonably Available Control Measures
(RACM) Requirement and Attainment Demonstration Submissions for
Ozone Nonattainment Areas.'' John S. Seitz, Director, Office of Air
Quality Planning and Standards. November 30, 1999. http://www.epa.gov/ttn/oarpg/t1/memoranda/revracm.pdf.
    \39\ Memorandum of December 14, 2000, from John S. Seitz,
Director, Office of Air Quality Planning and Standards, re:
``Additional Submission on RACM from States with Severe One-Hour
Ozone Nonattainment Area SIPs.'' http://www.epa.gov/ttn/caaa/t1/memoranda/121400_racmmemfin.pdf.
---------------------------------------------------------------------------

b. Final Action and Rationale
    The EPA is finalizing the proposed approach of continuing to apply
existing RACM guidance to the 2008 ozone NAAQS, such that we interpret
the RACM provision to require a demonstration that the state has
adopted all reasonable measures (including RACT) to meet RFP
requirements and to demonstrate attainment as expeditiously as
practicable and thus that no additional measures that are reasonably
available will advance the attainment date or contribute to RFP for the
area. Additionally the EPA is finalizing the interpretation of the CAA
requirements that states should consider all available measures,
including those being implemented in other areas, and that a state must
adopt measures for an area only if those measures are economically and
technologically feasible and will advance the attainment date or are
necessary for RFP. This interpretation has been upheld by several
courts. See, e.g., Sierra Club v. EPA, et al., 294 F.3d 155 (D.C.
Circuit, 2002).
    Significant tracts of land under federal management may also be
included in nonattainment area boundaries. The role of fire in these
areas should be assessed and emissions budgets developed in concert
with those federal land management agencies. Where appropriate, states
may consider developing plans for addressing wildland fuels in
collaboration with land managers and owners. Information is available
from the Department of the Interior (DOI) and USDA Forest Service on
smoke management programs and

basic smoke management practices and may be considered as potential
mitigation measures to lessen the impacts of wildfires.\40\
---------------------------------------------------------------------------

    \40\ USDA Forest Service and Natural Resources Conservation
Service, Basic Smoke Management Practices Tech Note, October 2011,
http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb1046311.pdf.
---------------------------------------------------------------------------

    Wildfire emissions are a component of background ozone \41\ and can
significantly contribute to periodic high ozone levels.\42\ Besides
their effect on air quality, wildfires pose a direct threat to public
safety--a threat that can be mitigated through management of wildland
vegetation. Attempts to suppress wildfires have resulted in unintended
consequences, including increased risks to both humans and
ecosystems.\43\ The use of wildland prescribed fire can influence the
occurrence, behavior and effects of catastrophic wildfires which may
help manage the contribution of wildfires to background ozone levels
and periodic peak ozone events. Additionally prescribed fires can have
benefits to those plant and animal species that depend upon natural
fires for propagation, habitat restoration, and reproduction, as well
as myriad ecosystem functions (e.g., carbon sequestration). The EPA
understands the importance of prescribed fire which mimics a natural
process necessary to manage and maintain fire-adapted ecosystems and
climate change adaptation, while reducing risk of uncontrolled
emissions from catastrophic wildfires, and is committed to working with
federal land managers, tribes, and states to effectively manage
prescribed fire use to reduce the impact of wildfire related emissions
on ozone.
---------------------------------------------------------------------------

    \41\ Jaffe, DA; Wigder, NL. (2012). Ozone production from
wildfires: A critical review. Atmos Environ 51: 1-10. http://dx.doi.org/10.1016/j.atmosenv.2011.11.063.
    \42\ Emery, C; Jung, J; Downey, N; Johnson, J; Jimenez, M;
Yarwood, G; Morris, R. (2012). Regional and global modeling
estimates of policy relevant background ozone over the United
States. Atmos Environ 47:206-217. http://dx.doi.org/10.1016/j.atmosenv.2011.11.012.
    \43\ Indeed, ``Fire policy that focuses on [wildfire]
suppression only, delays the inevitable, promising more dangerous
and destructive future . . . fires.'' Stephens, SL; Agee, JK; Fule,
PZ; North, MP; Romme, WH; Swetnam, TW. (2013). Managing Forests and
Fire in Changing Climates. Science 342:41-42.
---------------------------------------------------------------------------

    If wildfire impacts are significant, contributing to exceedances of
the standard, states should consider RACM for this source. Fires play
an important ecological role across the globe, benefiting those plant
and animal species that depend upon natural fires for propagation,
habitat restoration, and reproduction. Fires are one tool that can be
used to reduce fuel load, unnatural understory, and tree density,
helping to reduce the risk of catastrophic wildfires. Some wildfires
and the use of prescribed fire can influence the occurrence of
catastrophic wildfires which may reduce the probability of fire-induced
ozone impacts and subsequent public health effects. RACM for wildfire
may include addressing the wildland fuels through fuels management,
including the use of prescribed fire and possibly allowing some
wildfire to occur naturally, in systems that are ecologically fire
dependent. Where appropriate, states, land managers and land owners may
consider developing plans to ensure that fuel accumulations are
addressed and fuel management efforts are not delayed. RACM for
prescribed fires should also be considered. Information is available
from DOI and the USDA Forest Service on the ecological role of fire,
smoke management programs and basic smoke management practices, and
fuels management strategies, and may be considered when determining
RACM for prescribed fires. RACM must be determined for each area on a
case-by-case basis.
c. Comments and Responses
    Comment: One commenter suggested amending RACM guidance to follow
the same common-sense approach proposed for RACT; i.e., if studies show
that reducing anthropogenic VOC emissions in an area has little effect
on ground-level ozone concentrations, RACM analyses should not be
required for that pollutant.
    Response: We note that existing EPA guidance already provides some
assistance to states with identifying the type of measures that might
be considered for RACM (See General Preamble, 57 FR 13549, April 16,
1992). If a state demonstrates that implementation of VOC emission
reduction measures will not contribute to an area's reasonable further
progress or to attainment, then additional control of VOC emissions
does not need to be further considered for RACM purposes. Thus, the EPA
concludes that it need not amend RACM guidance to address this comment.

E. Does the 2008 ozone NAAQS result in any new vehicle I/M programs?

    Based on current designations and classifications for the 2008
ozone NAAQS, no new vehicle I/M programs are currently required. In the
proposal for this rulemaking, the EPA provided information on potential
ways a state could design and implement an I/M program, either because
it was required to implement a program due to a future reclassification
for the 2008 ozone NAAQS, as a result of a nonattainment designation
and classification under a future standard, or because an area decided
to implement an I/M program even though it was not otherwise required.
That discussion is not repeated here; therefore, please refer to the
proposal (78 FR 34194-34196). Although the EPA is finalizing its
proposal to revise the I/M SIP due date to align it with other SIP due
dates (see section III.A of this preamble), no other changes are being
made to the EPA's existing regulations and guidance on vehicle I/M
programs.

F. How does transportation conformity apply to the 2008 ozone NAAQS?

1. What is transportation conformity?
    Transportation conformity is required under CAA section 176(c) to
ensure that transportation plans, transportation improvement programs
(TIPs) and federally supported highway and transit projects are
consistent with (``conform to'') the purpose of the SIP. Conformity to
the purpose of the SIP means that transportation activities will not
cause new air quality violations, worsen existing violations, or delay
timely attainment of the relevant NAAQS or interim reductions and
milestones. Transportation conformity applies to areas that are
designated nonattainment, and to those former nonattainment areas that
have been redesignated to attainment since 1990 and have a CAA section
175A maintenance plan (``maintenance areas'') for transportation-
related criteria pollutants: carbon monoxide, ozone, nitrogen dioxide
and particulate matter.
    The EPA's Transportation Conformity Rule (40 CFR 51.390 and part
93, subpart A) establishes the criteria and procedures for determining
whether transportation activities conform to the SIP. The EPA first
promulgated the Transportation Conformity Rule on November 24, 1993 (58
FR 62188), and subsequently published several amendments. For example,
the EPA published a final rule on July 1, 2004 (69 FR 40004) that
provided transportation conformity procedures for state and local
agencies under the 1997 ozone NAAQS, among other things. Parties
involved in implementing transportation conformity include state and
local transportation and air quality agencies, metropolitan planning
organizations (MPOs) and the U.S. Department of Transportation (the
DOT) (40 CFR 93.102). For further information on transportation
conformity rulemakings, policy guidance and outreach materials, see the

EPA's Web site at http://www.epa.gov/otaq/stateresources/transconf/index.htm.
2. When would transportation conformity apply to areas designated
nonattainment for the 2008 ozone NAAQS?
    Transportation conformity for the 2008 ozone NAAQS applied 1 year
after the effective date of nonattainment designations for the NAAQS.
CAA section 176(c)(6) and 40 CFR 93.102(d) provide a 1-year grace
period from the effective date of an initial designation of
nonattainment before transportation conformity applies in the area for
a particular pollutant and standard. For areas designated nonattainment
effective July 20, 2012, the 1-year grace period ended on July 20,
2013. For any area subsequently redesignated to nonattainment (from
unclassifiable or attainment), the 1-year grace period runs from the
effective date of the redesignation. The grace period requirements
differ depending on whether the nonattainment area is a metropolitan
area or an isolated rural area.
    In metropolitan areas, which are defined as urbanized areas that
have a population greater than 50,000 and a designated MPO responsible
for transportation planning per 23 U.S.C. 134, within 1 year after the
effective date of the nonattainment designation, the area's MPO and the
DOT must make a conformity determination with regard to the area's
transportation plan and TIP for the 2008 ozone NAAQS under the
transportation conformity regulations (40 CFR 51.390 and part 93,
subpart A). The conformity requirements for ``donut areas,'' \44\
including the application of the 1-year conformity grace period, are
generally the same as those for metropolitan areas. If, at the end of
the grace period, the MPO and the DOT have not made a transportation
plan and TIP conformity determination for the relevant pollutant and
standard, the area would be in a conformity ``lapse.'' During a
conformity lapse, only certain projects can receive additional federal
funding or approvals to proceed. The practical impact of a conformity
lapse will vary from area to area.
---------------------------------------------------------------------------

    \44\ For the purposes of transportation conformity, a ``donut''
area is the geographic area outside a metropolitan planning area
boundary, but inside a designated nonattainment or maintenance area
boundary that includes an MPO (40 CFR 93.101).
---------------------------------------------------------------------------

    Isolated rural nonattainment areas are areas that do not contain or
are not part of an MPO (40 CFR 93.101). Conformity requirements for
isolated rural nonattainment areas can be found at 40 CFR 93.109(g). An
isolated rural area would be required to make a conformity
determination only at the point when a new transportation project needs
funding or approval. This point may occur significantly after the 1-
year grace period has ended. See the EPA's July 1, 2004, final rule for
further background on how the EPA has implemented this conformity grace
period for the 1997 ozone NAAQS in metropolitan, donut and isolated
rural areas (69 FR 40008-40014).\45\
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    \45\ Also, see the EPA's transportation conformity Web site for
more information, including EPA's ``Transportation Conformity
Guidance for 2008 Ozone NAAQS Nonattainment Areas'' at: http://www.epa.gov/otaq/stateresources/transconf/2008naaqs.htm.
---------------------------------------------------------------------------

3. Does transportation conformity apply for the 1997 ozone NAAQS once
that NAAQS is revoked?
    The CAA only requires transportation conformity in areas that are
designated nonattainment or maintenance for a given pollutant and
standard. Therefore, transportation conformity would no longer apply
for purposes of the 1997 ozone NAAQS as of the time that standard (and
thus an area's designation for that standard) is revoked. Accordingly,
existing 1997 ozone NAAQS nonattainment and maintenance areas,
regardless of their designation for the 2008 ozone NAAQS, would no
longer be required to demonstrate transportation conformity for the
1997 ozone NAAQS after the 1997 ozone NAAQS is revoked. The D.C.
Circuit ruled that the EPA violated the CAA when it partially revoked
the 1997 ozone NAAQS for transportation conformity purposes only in the
Classifications Rule for the 2008 ozone NAAQS (NRDC v. EPA, D.C. Cir.
No. 12-1321, December 23, 2014). The partial revocation had been in
effect since July 20, 2013, 1 year after the effective date of
designations for the 2008 ozone NAAQS. (77 FR 30160). The D.C. Circuit
Court of Appeals vacated this aspect of the Classifications Rule but
said nothing to suggest that the EPA could not revoke the standard for
all purposes, as it is doing today. See South Coast, (upholding
revocation of standard so long as anti-backsliding measures are
introduced). Under our current Transportation Conformity Rule, the
latest approved or adequate emission budgets for a previous ozone NAAQS
(i.e., the 1997 or the 1-hour ozone NAAQS) would continue to be used in
conformity determinations for the 2008 ozone NAAQS until emission
budgets are established and found adequate or are approved for the 2008
ozone NAAQS. (77 FR 14981-2).
4. What impact will the implementation of the 2008 ozone NAAQS have on
a state's Transportation Conformity SIP?
    States with previously approved Transportation Conformity SIPs
should not need to revise those SIPs, unless they need to do so to
ensure that existing state regulations apply in areas newly designated
nonattainment for the 2008 ozone NAAQS. However, if this is the first
time that transportation conformity will apply in a state, such a state
is required to submit a SIP revision within 12 months of the effective
date of the nonattainment designation that covers the three specific
transportation conformity requirements that are delineated in CAA
section 176(c)(4)(E). These specific requirements are consultation
procedures and written commitments to control or mitigation measures
associated with conformity determinations for transportation plans,
TIPs or projects. 40 CFR 51.390. Additional information and guidance
can be found in EPA's ``Guidance for Developing Transportation
Conformity State Implementation Plans'' (http://www.epa.gov/otaq/stateresources/transconf/policy/420b09001.pdf).

G. What requirements for general conformity apply to the 2008 ozone
NAAQS??

1. Summary of the Proposal
    The EPA did not propose to make revisions to the General Conformity
Regulations.\46\ However, we did recommend that as areas develop their
SIPs for the 2008 ozone NAAQS, state and local air quality agencies
work with federal agencies with major facilities that are subject to
the General Conformity Regulations to establish an emissions budget for
those facilities in order to facilitate future conformity
determinations. Significant tracts of land under federal management may
also be included in nonattainment area boundaries. The role of fire in
these areas should be assessed and emissions budgets developed in
concert with those federal land management agencies. Where appropriate,
states may consider developing plans for addressing wildland fuels in
collaboration with land managers and owners. Information is available
from DOI and USDA Forest Service on the ecological role of fire, smoke
management programs and basic

smoke management practices, and fuels management strategies (including
prescribed fire), and may be considered as potential mitigation
measures to lessen the impacts of wildfires.\47\ We also stated in the
proposal that for the ozone precursors VOC and NOX, the
existing de minimis emission levels contained in 40 CFR 93.153(b)(1)
will continue to apply to the 2008 ozone NAAQS. We also stated in the
proposal that general conformity for the 2008 ozone NAAQS would apply 1
year after the effective date of nonattainment designations for that
NAAQS because section 176(c)(6) provides a 1-year grace period from the
effective date of initial designations before general conformity
determinations are required in areas newly designated nonattainment for
a particular pollutant and standard. In such areas, we encourage states
to consider in any baseline inventory used and/or submitted to include
emissions expected from projects subject to general conformity,
including emissions from wildland fire that may be reasonably expected
in the area.
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    \46\ Information on what federal actions are covered and how to
demonstrate conformity are found in 40 CFR part 93 subpart B. On
March 24, 2010, former Administrator Lisa P. Jackson signed the
General Conformity Final Rule ``Revisions to the General Conformity
Regulations,'' which was published April 5, 2010 (75 FR 17254-
17279). More information on the general conformity program is
available at http://www.epa.gov/air/genconform/.
    \47\ USDA Forest Service and Natural Resources Conservation
Service, Basic Smoke Management Practices Tech Note, October 2011,
http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb1046311.pdf.
---------------------------------------------------------------------------

    Since we proposed to revoke the 1997 ozone NAAQS at the time the
final SIP Requirements Rule is published in the Federal Register, we
stated in the proposal that general conformity requirements under the
1997 ozone NAAQS would end after the 2008 ozone NAAQS general
conformity requirements begin.
2. Final Action and Rationale
    The EPA is taking no action to revise General Conformity
Regulations. For reasons explained in section IV of this rule, we are
revoking the 1997 ozone NAAQS 30 days after publication of this final
rule. Accordingly, the general conformity requirements for the 1997
ozone NAAQS will end when the NAAQS is revoked, and the general
conformity requirements for the 2008 ozone NAAQS are applicable 1 year
after the effective date of nonattainment designations for the 2008
NAAQS.\48\ The EPA believes the existing General Conformity Regulations
(40 CFR part 93) remain appropriate for the 2008 ozone NAAQS. States
with approved general conformity SIPs should not need to revise their
SIPs unless they need to do so to ensure they are consistent with the
April 5, 2010, revisions to the general conformity regulations or to
ensure the existing regulations apply in the appropriate newly
designated areas.
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    \48\ For areas designated in 2012, the effective date was July
20, 2013.
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H. What are the requirements for contingency measures in the event of
failure to meet a milestone or to attain?

1. Summary of Proposal
    The EPA proposed that the contingency measures required for
Moderate and above areas under CAA sections 172(c)(9) and 182(c)(9)
must provide for the implementation of specific measures if the area
fails to attain or to meet any applicable milestone. These measures
must be submitted for approval into the SIP as adopted measures that
would take effect without further rulemaking action by the state or the
Administrator upon a determination that an area failed to attain or to
meet the applicable milestone. Per the EPA guidance, contingency
measures should represent 1-year's worth of progress, amounting to
reductions of 3 percent of the baseline emissions inventory for the
nonattainment area, which would be achieved while the state is revising
its plans for the area.\49\
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    \49\ See the April 16, 1992 General Preamble section III.A.3.c
(57 FR 13498 at 13511).
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    Regarding the content of the contingency measures, the EPA's prior
guidance specifies that some portion of the contingency measures must
include VOC reductions. As explained in the proposal, this previous
limitation is no longer necessary in all cases. In particular, Moderate
and above areas that have completed the initial 15 percent VOC
reduction required by CAA section 182(b)(1)(A)(i), can meet the
contingency measures requirement based entirely on NOX
controls if that is what the state's analyses have demonstrated would
be most effective in bringing the area into attainment. There would be
no minimum VOC requirement. Also, the EPA proposed continuing its long-
standing policy that allows promulgated federal measures to be used as
contingency measures as long as they provide emission reductions in the
relevant years in excess of those needed for attainment or RFP.\50\
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    \50\ See Louisiana Environmental Action Network (LEAN) v. EPA,
382 F.3d 575 (D.C. 2004).
---------------------------------------------------------------------------

    The EPA also proposed an implementation approach for Extreme
nonattainment areas whereby plan provisions meeting the requirements of
CAA section 182(e)(5) (referred to as the ``black box''), including the
requirements concerning contingency measures, therein, may satisfy the
CAA section 172(c)(9) and 182(c)(9) contingency measure requirements
for the area provided the state has already adopted all reasonable
candidate measures in the applicable SIP to satisfy RACM, RFP, and all
other requirements necessary for attainment in the area.
2. Final Action and Rationale
    The EPA is finalizing the proposed requirements that contingency
measures must be submitted for approval into the SIP as required by the
CAA and must provide for the implementation of specific measures
without any further rulemaking action if the area fails to attain or
meet any applicable milestone, with limited exceptions for Extreme
nonattainment areas relying on plan provisions approved under CAA
section 182(e)(5), as discussed below. Regarding content of the 1-
year's worth of emissions covered by the contingency measures, the EPA
is finalizing its proposal to allow the 3 percent emissions reductions
of the contingency measures, to be based entirely on NOX
controls if the area has completed the initial 15 percent ROP VOC
reduction required by CAA section 182(b)(1)(A)(i) and the state's
analyses have demonstrated that NOX substitution would be
most effective in bringing the area into attainment.
    The EPA will continue to allow the use of federal measures
providing ongoing reductions into the future to be used meet
contingency measure requirements for the 2008 ozone NAAQS, consistent
with the EPA's longstanding policy. The EPA has previously approved the
use of federal measures to meet contingency measure requirements in
actions approving 1-hour and 8-hour ozone SIPs.
    With respect to Extreme ozone nonattainment areas, CAA section
182(e)(5) allows the agency to exercise discretion in approving Extreme
area attainment plans that rely, in part, on the future development of
new control technologies or improvements of existing control
technologies, where certain conditions are met. This discretion can be
applied as long as the state has demonstrated that: All reasonably
available control measures, including RACT, have been included in the
plan; the area's RFP demonstration during the first 10 years after
designation does not rely on anticipated future technologies; and the
state has submitted enforceable commitments to timely develop and adopt
contingency measures to be implemented if the anticipated future
technologies do not achieve planned reductions. The EPA is finalizing
its proposal to allow states to submit, for Extreme nonattainment
areas, enforceable commitments to develop and adopt contingency
measures meeting the requirements of

182(e)(5) to satisfy the requirements for both attainment contingency
measures in CAA sections 172(c)(9) and 182(c)(9). These enforceable
commitments must obligate the state to submit the required contingency
measures to the EPA no later than three years before any applicable
implementation date, in accordance with CAA section 182(e)(5).\51\ We
note that this does not, however, relieve states from obligations to
submit contingency plans as required by CAA sections 172(c)(9) and
182(c)(9) for periods in the first 10 years after designation.
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    \51\ For example, where a state intends to rely on CAA section
182(e)(5) commitments to satisfy the CAA section 182(c)(9)
contingency measure requirement for an RFP milestone in year 2022,
the commitments must obligate the state to submit adopted
contingency measures to the EPA no later than 2019. (i.e., 3 years
before RFP contingency measures for 2022 would be implemented.
---------------------------------------------------------------------------

3. Comments and Responses
    Comment: Commenters urged the EPA to provide flexibility to states
when adopting, subject to the EPA approval, contingency measures into
the SIP that are ready for implementation should the area fail to
either meet milestones or attain. Commenters requested that the EPA
allow air quality improvement measurements to be taken into
consideration for purposes of evaluating the level of emission
reductions necessary to meet the contingency measure requirements when
providing ``approximately'' 1 year's worth of progress for contingency
measures. Commenters indicated that a similar air quality improvements
approach has been used in approving PM2.5 contingency
measures.
    Response: The EPA's long-standing interpretation is that a 3
percent emissions reduction from the RFP baseline, rather than a
specific ozone concentration improvement, is the minimum contingency
measure adoption requirement under subpart 2. The EPA did not propose
to alter this guidance. However, we note that if the contingency
measures are ever triggered for an area, states may take air quality
considerations into account in determining whether a subset of measures
amounting to less than 3 percent emissions reduction are all that is
necessary to be implemented to cure the identified failure.\52\ The
implementation of PM2.5 NAAQS is governed by statutory and
regulatory requirements that are separate from, and not identical to,
ozone implementation and provide flexibility for states to consider the
degree of air quality improvement that may be needed in developing RFP
plans and contingency measures.
---------------------------------------------------------------------------

    \52\ See ``Guidance for Growth Factors, Projections, and Control
Strategies for the 15 Percent Rate-of-Progress Plans,'' U.S. EPA,
March 1993, page 83 (EPA-452/R-93/002).
---------------------------------------------------------------------------

    Comment: Several commenters supported, and no commenters objected
to using CAA section 182(e)(5) authority to approve contingency measure
plans for Extreme nonattainment areas where the attainment plan is
based on development of new or improved control measures.
    Response: We appreciate the supportive comments. We recognize that
all areas must meet the contingency plan requirements of CAA sections
172(c)(9) and 182(c)(9). We agree that CAA section 182(e)(5) provides
the agency with discretion to approve an Extreme area attainment plan
that relies, in part, on the future development of new control
technologies or improvements of existing control technologies. This
authority can be exercised as long as the state has demonstrated that:
All reasonably available control measures, including RACT, have been
included in the plan; the area's RFP demonstration during the first 10
years after designation does not rely on anticipated future
technologies; and the state has submitted enforceable commitments to
timely develop and adopt contingency measures in the event that
anticipated future technologies do not achieve planned reductions.
    Comment: One commenter argued that an Extreme nonattainment area
seeking to rely on the CAA section 182(e)(5) ``black box'' should be
required to demonstrate that it has adopted all feasible controls, even
if they do not advance attainment by a year and regardless of whether
they constitute ``reasonably available control measures,'' and that the
EPA should ``change its interpretation of RACT and RACM, which
currently allows areas to avoid adopting and implementing feasible
measures.''
    Response: The EPA believes that both its long-standing
interpretation of RACM and its focus on whether control measures are
``reasonably available'' provide an appropriate framework for
determining when to exercise the discretion provided by CAA section
182(e)(5). As noted in the proposal, the determination of whether a SIP
contains all RACM requires an area-specific analysis establishing that
there are no additional economically and technically feasible control
measures (alone or cumulatively) that will advance the attainment date
by 1 year. This requires close review of any measure that a commenter
identifies as reasonably available for implementation in the area in
light of local circumstances, and of measures being implemented in
other states. 78 FR 34187, at 34194 (June 6, 2013). This interpretation
of RACM has been upheld in court (e.g., Sierra Club v. EPA, 294 F.3d
155, 162-163 (D.C. Cir. 2002)). Thus, the EPA believes that it is
appropriate to require that an area seeking to rely on the anticipated
development of new technology demonstrate that its plan includes all
control measures that come within this definition of ``reasonably
available.'' The EPA does not believe it is necessary for an area to
demonstrate the use of measures that go beyond that definition in order
to meet contingency measure requirements.

I. How do the NSR requirements apply for the 2008 ozone NAAQS?

1. Major NSR Requirements for the 2008 Ozone NAAQS
    The NSR programs established in parts C and D of title I of the CAA
contain specific requirements for the preconstruction review and
permitting of new or modified major stationary sources of air
pollutants. In attainment and unclassifiable areas, the requirements
under part C apply for the prevention of significant deterioration
(PSD) program. In nonattainment areas, the requirements under part D
apply for the nonattainment NSR program. We commonly refer to the PSD
and nonattainment NSR programs together as the ``major NSR programs.''
    The regulations for the major NSR programs are contained in 40 CFR
51.166 and 52.21 for PSD, and 51.165, 52.24 and part 51, Appendix S for
nonattainment NSR.\53\ Among other things, in unclassifiable and
attainment areas, the PSD program requires a new major source, or a
major modification to an existing major source, to obtain a permit that
satisfies PSD requirements, including the application of best available
control technology (BACT) for ``each pollutant subject to regulation
under [the CAA],'' conducting an air quality impact analysis, and
complying with requirements related to the protection of Class I areas.
---------------------------------------------------------------------------

    \53\ As appropriate, certain nonattainment NSR requirements
under 40 CFR 51.165 or Appendix S can also apply to sources and
modifications located in areas that are designated attainment or
unclassifiable in the Ozone Transport Region. See, e.g., CAA
184(b)(2), 40 CFR 52.24(k).
---------------------------------------------------------------------------

    As part of the required air quality impact analyses, section
165(a)(3) of the CAA provides that the owner or operator of a proposed
facility must, among other things, demonstrate that ``emissions from
construction or operation of such facility will not cause,

or contribute to, air pollution in excess of any . . . national ambient
air quality standard in any air control region.'' The EPA has generally
interpreted this statutory requirement, and the corresponding
regulations implementing EPA's federal PSD permitting program at 40 CFR
52.21(k) and establishing minimum requirements for PSD programs
approved into SIPs at 40 CFR 51.166(k), to include a demonstration for
any NAAQS that is in effect at the time a final permit decision is
issued.\54\ See, e.g., 73 FR 28321, 28324, 28340 (May 16, 2008); 78 FR
3253 (Jan. 15, 2013); Memorandum from Stephen D. Page, Director, Office
of Air Quality Planning & Standards, entitled ``Applicability of the
Federal Prevention of Significant Deterioration Permit Requirements to
New and Revised National Ambient Air Quality Standards,'' to the EPA
Regional Air Division Directors and Deputies (April 1, 2010).
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    \54\ The EPA received comments relating to statements in the
proposal about its discretion to grandfather permit applications in
appropriate circumstances. Since this NAAQS has been in effect since
2008, the EPA is not adding a grandfathering provision in this final
rule and those comments are discussed further in the Response to
Comments document.
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    In the proposal, the EPA indicated that, since the May 27, 2008,
effective date of the 2008 ozone NAAQS, permit applications for new
major stationary sources and major modifications have been subject to
the PSD program requirements for ozone under two sets of circumstances:
(1) Prior to the designation of areas for the 2008 ozone NAAQS, sources
locating in areas designated attainment or unclassifiable for the 1997
ozone NAAQS; and (2) on and after the July 20, 2012, effective date of
area designations for the 2008 ozone NAAQS, sources locating in areas
designated as attainment or unclassifiable for both the 1997 and 2008
ozone NAAQS. If, however, an area was designated attainment or
unclassifiable for the 2008 ozone NAAQS on and after July 20, 2012, but
was designated nonattainment for the 1997 ozone NAAQS, consistent with
the PSD regulations at 40 CFR 51.166(i)(2) and 52.21(i)(2), the
nonattainment designation would require application of nonattainment
NSR for permits issued to new and modified sources locating in that
area that trigger major NSR requirements for ozone until the revocation
of the 1997 ozone NAAQS is effective. In this rulemaking, the EPA is
revoking the 1997 ozone NAAQS for all purposes. Accordingly, as
explained in section IV.A of this preamble, as of 30 days after the
publication of this rule in the Federal Register, the area designations
for the 1997 ozone NAAQS will no longer be considered current
designations; thus, all areas designated attainment for the 2008 ozone
NAAQS will be subject to PSD requirements. In the proposal, the EPA
explained that this result was based on its interpretation of the PSD
regulations at 40 CFR 51.166(i)(2) and 52.21(i)(2), but recognized that
those provisions did not expressly say that a nonattainment designation
for a revoked standard does not trigger the exemption from PSD
requirements contained in those provisions. 78 FR 34216-17.
Accordingly, the EPA requested comment on whether amendment of 40 CFR
51.166(i)(2) and 52.21(i)(2) is necessary to achieve that outcome and
on how such an amendment, if any, should be worded. After additional
consideration, we believe there is a need for us to amend these
provisions to further clarify the application of the exemption they
contain. Therefore, the EPA is amending its PSD regulations at 40 CFR
51.166(i)(2) and 52.21(i)(2) as a logical outgrowth of the proposal and
the submitted comments to clarify that historical designations for a
revoked NAAQS should not be considered in determining whether PSD
requirements apply for that pollutant once the revocation becomes
effective in an area.
    For any area that is designated nonattainment for the 2008 ozone
NAAQS, the historical designations and classifications resulting from
the revoked 1997 ozone NAAQS will continue to serve to identify
nonattainment NSR anti-backsliding requirements (i.e., major source
thresholds and emissions offset ratios) that need to be taken into
account in issuing nonattainment NSR permits to major stationary
sources and major modifications.\55\ As indicated previously, the
designations and classifications for the revoked standard should not be
regarded as current designations and classifications once the
revocation takes effect. For example, in implementing the emissions
offset requirements for nonattainment NSR, offset ratios based on the
classification for the revoked standard, to the extent more stringent
than the ratios for the 2008 ozone NAAQS classification, must be used
for anti-backsliding purposes. However, for purposes of determining
whether a prospective offset can be obtained from a nonattainment area
other than the one in which a new or modified source would be located,
the requirements under section 173(c)(1) of the CAA must be satisfied.
CAA section 173(c)(1) requires, in part, that the nonattainment area
from which the offset is obtained must have ``an equal or higher
nonattainment classification than the area in which the [new or
modified] source is located. . . .'' After the revocation takes effect,
the historical classification for the revoked NAAQS, to the extent that
it is lower than the classification in the nonattainment area where a
new or modified source would be located, would not preclude obtaining
the offset from that area, so long as (1) the current classification
for the ozone NAAQS for that area is equal to or higher than the
current classification of the nonattainment area where the new or
modified source is locating and (2) the other requirements under
section 173(c)(1) of the CAA are satisfied.
---------------------------------------------------------------------------

    \55\ In this final rule, the anti-backsliding requirements for
nonattainment NSR are codified in 40 CFR 51.1105, and are described
in Section IV.B of this preamble. The nonattainment NSR regulations
at 40 CFR 51.165 have been amended in this final rule to add new
paragraph (a)(12), which references those anti-backsliding
requirements. Also, as proposed, a new section VII has been added to
Appendix S to set forth the anti-backsliding requirements that must
be followed when states issue nonattainment NSR permits under that
Ruling.
---------------------------------------------------------------------------

    Some states may have already in their SIP a nonattainment NSR
program consistent with part D of the CAA that can be applied to new
nonattainment areas. In such situations, permitting authorities should
have begun applying the nonattainment NSR requirements in permitting
actions for new and modified major sources that trigger major source
permitting requirements for ozone in new nonattainment areas starting
from the effective date of the 2008 ozone designations (July 20, 2012).
    For a newly designated (or redesignated) nonattainment area for the
2008 ozone NAAQS in a state with a SIP that specifically lists the
areas in which nonattainment NSR requirements under part D apply, or in
a state that currently has no approved nonattainment NSR program, there
will be an interim period between the July 20, 2012, designation date
and the date when the EPA approves the state's amended SIP, which must
be revised to adequately address the nonattainment NSR requirements for
the 2008 ozone NAAQS contained in this final rule. In the proposal, we
explained that during this interim period, nonattainment NSR
requirements for the 2008 NAAQS are governed by the EPA's Emission
Offset Interpretative Ruling codified in Appendix S to 40 CFR part 51.
Among other things, in general, Appendix S requires new or modified
major sources in nonattainment areas to meet the lowest achievable
emission rate (LAER) and obtain sufficient offsetting

emissions reductions to assure that the new or modified major sources
will not interfere with the area's progress toward attainment. In
addition, a new section VII of Appendix S has been added as part of
this final rule to set forth the anti-backsliding requirements that
must be addressed in order to issue a nonattainment NSR permit under
Appendix S. That language for section VII is being finalized with only
minor modifications to what was proposed. Readers should refer to 40
CFR part 51, Appendix S for a better understanding of the Appendix S
permitting requirements.
    In the proposal, the EPA explained that the time period for the NSR
waiver provision contained in section VI of Appendix S, enabling
permitting authorities in specified circumstances to issue
nonattainment NSR permits that do not require LAER or emissions offsets
as are otherwise required under section IV of appendix S, was limited
by the court's ruling in NRDC v. EPA, 571 F.3d 1245 (D.C. Cir. 2009).
The court's ruling was the result of a petition filed in response to
the EPA's Phase 2 Rule for the 1997 ozone NAAQS in which the EPA
revised 40 CFR 52.24(k). The revision to paragraph (k) eliminated
language stating that if a nonattainment area did not have an approved
nonattainment NSR program within 18 months after designation, Appendix
S would no longer apply and a construction ban would apply instead. 70
FR 71612 (November 29, 2005). The effect of the revision was to extend
the applicability of Appendix S, including the section VI waiver
provision, to cover the full period from the date of designation to the
date on which the EPA approved the nonattainment NSR SIP for a new
NAAQS.
    In NRDC v. EPA (571 F.3d 1245 (D.C. Cir. 2009)), the court vacated
``the elimination of the 18-month time limit for NSR waivers under
Appendix S'' on the grounds that it violated section 172(e) of the CAA
(571 F.3d at 1276). As a result of the court's vacatur of the extension
of the 18-month time limit for section VI of Appendix S, no section VI
waivers may be granted beyond 18 months from the date of designation
for any NAAQS.
    Several commenters requested that the EPA clarify how the court's
decision affects the implementation of Appendix S as an interim
nonattainment NSR program. While most commenters understood that the
vacatur applied only to the removal of the 18-month deadline for the
section VI waiver, one commenter seemed to interpret the vacatur to
apply to appendix S in its entirety.
    To clarify, there is now a distinction between the length of time
during which waivers may be granted under section VI of Appendix S and
the length of time the remainder of Appendix S applies as an interim
nonattainment NSR program. No section VI waivers may be granted beyond
18 months from the date of designation. The remainder of Appendix S,
however, is not subject to an 18-month time limitation. It will remain
as the basis for air agencies to issue nonattainment NSR permits in new
ozone nonattainment areas until the EPA approves a state's
nonattainment NSR program for the 2008 ozone NAAQS under the SIP for
the area. Specifically, section IV of Appendix S contains
preconstruction requirements for proposed sources and modifications,
which reflect the requirements contained in part D of the CAA for ozone
nonattainment areas. The requirements in section IV should be met
consistent with the anti-backsliding requirements contained in new
section VII of Appendix S.
2. Offset Requirements and Policy
    To satisfy requirements under section 173 of the Act, new and
modified major sources in nonattainment areas must secure emissions
reductions (i.e., ``offsets'') to compensate for a proposed emissions
increase. Offsets are generated by emissions reductions that meet
specific creditability criteria set forth by the SIP consistent with
EPA regulations. See, 40 CFR 51.165(a)(3)(ii)(A)-(J) and part 51
Appendix S section IV.C.\56\ One commenter suggested that nonattainment
NSR major source construction and major modification offsets should be
available outside the nonattainment area (from attainment areas) due to
the possibility that new sources would develop in attainment areas in
close proximity to the boundary of the ozone nonattainment area with
subsequent impact on the nonattainment area. Further, the commenter
seemed to suggest that emissions reductions from these close proximity
sources should also be allowed to be used as offsets within the
adjacent nonattainment area. The commenter's suggestion fails to
address the statutory requirements for offsets and, more specifically,
does not confront the statutory provisions restricting where offsets
can be obtained from. In accordance with the requirements under section
173(c)(1) of the CAA, emissions offsets must be obtained from the same
nonattainment area, except that the state may allow a source to obtain
offsets from another nonattainment area if (1) that area has an equal
or higher nonattainment classification than the nonattainment area in
which the source requiring the offsets is located, and (2) emissions
from that other area contribute to a violation of the NAAQS in the
nonattainment area in which the source requiring the offsets is
located. Accordingly, the EPA does not intend to revise the existing
requirements as to where emissions offsets may be obtained to allow use
of offsets from attainment areas.
---------------------------------------------------------------------------

    \56\ See also, the EPA's ``Improving Air Quality with Economic
Incentive Programs'' document at http://www.epa.gov/region07/air/nsr/nsrmemos/eipfin.pdf. For additional memoranda and guidance
documents, see http://www.epa.gov/region7/air/nsr/nsrindex.htm.
---------------------------------------------------------------------------

3. Facilitating New Source Growth in Nonattainment Areas
a. Offset Banks
    States can help facilitate continued economic development in a
nonattainment area by establishing offset banks or registries. Such
banks or registries can help new or modified major stationary source
owners meet offset requirements by streamlining identification and
access to available emissions reductions. Some states have established
offset banks to help ensure a consistent method for generating and
transferring NOX and VOC offsets.\57\ Offsets in these areas
are generated by emissions reductions that meet specific creditability
criteria set forth by the SIP consistent with EPA regulations. See
existing 40 CFR 51.165(a)(3)(ii)(A)-(J) and part 51 Appendix S section
IV.C.
---------------------------------------------------------------------------

    \57\ See, for example, emission reduction credit banking
programs in Ohio (OAC Chapter 3745-1111) and California (H&SC
Section 40709).
---------------------------------------------------------------------------

b. Interprecursor Offset Substitution
    In the proposal, the EPA recognized that states could establish
interprecursor \58\ offset substitution provisions, which would create
additional flexibility in meeting offset requirements by allowing
NOX emissions reductions to satisfy VOC offset requirements
and vice versa. See 78 FR at 34201. The EPA received no adverse
comments on whether to allow such interprecursor trading for ozone and
no comment suggested that such trading is not or should not be allowed
for ozone. In fact, all comments addressing the EPA's statements in the
proposal concerning interprecursor trades for ozone for nonattainment
NSR permitting were in support of allowing NOX emissions
reductions to satisfy VOC offset requirements and vice versa.
---------------------------------------------------------------------------

    \58\ For purposes of this rulemaking, we are using the terms
interprecursor and interpollutant interchangeably.

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

    Although there were no adverse comments relating to the EPA's
ability to allow interprecursor trading for ozone, the EPA recognizes
that the current language of 40 CFR 51.165(a)(11) and part 51 Appendix
S IV.G.5 could be read to limit interprecursor trading to
PM2.5, and thus to preclude this kind of interprecursor
trading for ozone precursors (NOX and VOC). However, the EPA
has issued previous guidance that clearly allows for such
interprecursor trading for ozone precursors.\59\ While the EPA did not
specifically propose to amend the nonattainment NSR regulations to
address interprecursor trading for ozone, the proposal indicated the
EPA's intent to continue to allow states to establish provisions that
allow for such interprecursor trading for ozone precursors.
---------------------------------------------------------------------------

    \59\ ``Improving Air Quality with Economic Incentive Programs''
document at http://www.epa.gov/region07/air/nsr/nsrmemos/eipfin.pdf.
In this document, the EPA stated: ``[o]zone interprecursor trading
can be used to meet NSR offset requirements, regardless of whether
the NSR offset emission reductions are generated through an EIP.''
Id. at 244. For additional memoranda and guidance documents, see
http://www.epa.gov/region7/air/nsr/nsrindex.htm.
---------------------------------------------------------------------------

    As noted previously, the EPA received no adverse comments on the
interprecursor aspect of the proposal. Commenters did, however,
indicate support for ensuring in the final rulemaking that
interpollutant trading would continue to be allowed, and one commenter
indicated support for measures similar to what was authorized in the
final 2008 PM2.5 NAAQS implementation rule, see 73 FR 28321,
which revised the regulations and Appendix S to allow for
interprecursor trading for PM2.5 precursors.
    Accordingly, the EPA is taking action in this final rulemaking to
amend the regulatory text in both 40 CFR 51.165 and Appendix S as a
logical outgrowth of the proposal and the submitted comments to ensure
that the offset provisions of both rules are consistent with our
proposal and our ongoing position to allow such trades for the ozone
precursors (VOC and NOX). See revised 40 CFR 51.165(a)(11)
and part 51 Appendix S IV.G.5. These changes in the regulatory text are
intended to clarify that interprecursor trading continues to be an
option for the ozone precursors VOC and NOX, as long as such
trades are consistent with existing policy and legal requirements;
these revisions are not intended to change the underlying requirements
for such trades. Please refer to the Response to Comments document in
the docket for this rulemaking for more detailed information and
responses to comments with respect to interprecursor trading concerns.
c. Economic Development Zones (EDZs)
    Section 173(a)(1)(B) of the CAA authorizes the Administrator, in
consultation with the Secretary of Housing and Urban Development (HUD),
to identify areas within nonattainment areas as ``zone[s] to which
economic development should be targeted.'' Under this section, new or
modified major stationary sources that locate in such a zone are
relieved of the NSR requirement to obtain emission offsets if (1) the
relevant SIP includes an NSR nonattainment program that has established
emission levels for new and modified major sources in the zone
(``growth allowance''), and (2) the emissions from new or modified
stationary sources in the zone will not cause or contribute to emission
levels that exceed such growth allowance. CAA section 172(c)(4) of the
CAA requires that the growth allowance be consistent with the
achievement of reasonable further progress, and that it will not
interfere with attainment of the applicable NAAQS by the applicable
attainment date for the nonattainment area. The EPA is willing to work
with HUD and states to identify potential areas that could be
identified as EDZs.
4. Deadline for Submitting Nonattainment NSR Program SIPs for 2008
Ozone NAAQS
    As explained in section III.A of this preamble, several commenters
noted that the EPA's proposed rulemaking did not address the SIP
submittal deadline for the nonattainment NSR program for the 2008 ozone
NAAQS. As explained in section III.A, the final rule includes a
deadline of 3 years from the effective date of designation for states
to submit their nonattainment NSR program SIPs for the 2008 ozone
NAAQS. The rationale for this deadline appears in section III.A of this
preamble.

J. What are the emission inventory and emission statement requirements?

1. Emission Inventory Requirements
a. Summary of the Proposal
    We proposed that states should rely on their 3-year cycle inventory
as described by the Air Emissions Reporting Requirements (AERR) to meet
182(a)(3)(A) periodic inventory obligations and that the emissions
reporting requirements of the AERR be applied to determine all of the
data elements required for such inventories (see, e.g., Tables 2A, 2B,
2C and 2D of 40 CFR part 51, subpart A, Appendix A). We also proposed
to follow our existing guidance, titled ``Public Hearing Requirements
for 1990 Base-Year Emissions Inventories for Ozone and Carbon Monoxide
Nonattainment Areas'' in implementing certain SIP adoption and
submission procedures for the emissions inventory requirements under
CAA sections 182(a)(1) and 182(a)(3)(A) for purposes of the 2008 ozone
NAAQS.
b. Final Action and Rationale
    We are generally finalizing as proposed, although in light of
comments received we made small changes to address reporting of ozone
season day and partial county emissions not currently addressed in the
AERR, as explained below. CAA section 182(a)(3)(A) requires that states
submit periodic emission inventories no later than the end of each 3-
year period after submission of the base year inventory for the
nonattainment area. This requirement applies to Marginal and above
ozone nonattainment areas. Thus, states must submit this periodic
inventory no later than the end of each 3-year period after submission
of the base year inventory for the nonattainment area. The periodic
inventory required by this final rule must include ozone season day
emissions of VOC and NOX for point, nonpoint and mobile
sources (on-road and non-road) and fire-related event emissions. On
December 4, 2008, the EPA promulgated the AERR rule (40 CFR 51, subpart
A). The AERR requires states to submit comprehensive statewide 3-year
cycle annual emission inventories (2008, 2011, 2014, etc.) for a number
of pollutants (see list provided at 40 CFR 51.15(a)) regardless of an
area's attainment status. During the submission of the 3-year cycle
inventories in accordance with the AERR, states may also submit ozone
season day emissions to meet the periodic inventory requirement of this
rule. If the periodic inventory required by this rule is not included
in the AERR submission, then it must be submitted to the EPA through
other mechanisms in coordination with the Regional Office. Emission
inventory elements submitted per the AERR that are relied on in the SIP
also need to be adopted through the SIP submittal requirements per 40
CFR 51.100 et seq.
    We are finalizing the requirement that states use the reporting
requirements of the AERR to determine the data elements required for
such inventories, while including an additional requirement to report
ozone season day emissions, as defined in this final rule, rather than
the AERR requirement for

annual emissions for both the base year inventory for the nonattainment
area and the periodic inventory. Additionally, the EPA has included
within 40 CFR 51.1100(bb) and (cc) of this final rule definitions
pertaining to base year inventory and the ozone season day emissions,
in response to several significant comments as explained in section
III.J.1.c of this rule. Accordingly, a base year inventory for the
nonattainment area is due no later than 2 years after the effective
date of designations, and the emissions included in this inventory must
be ozone season day emissions as defined in CAA section 51.1100(cc) of
this rule. A periodic inventory must be submitted on intervals no later
than the end of each 3-year period after submission of the base year
inventory for the nonattainment area.
    The EPA has concluded that ozone season day emissions are the most
appropriate temporal basis for developing the emissions to be included
in this inventory, rather than summer day emissions as required by past
implementation rules or the AERR. The EPA believes that summer day
emissions required previously are an insufficient nomenclature, since
in some areas nonattainment may be due to ozone exceedances in months
other than summer months (e.g., wintertime), and necessitate focusing
planning efforts on emissions occurring during the most relevant time
period. Other than changing the name to be more inclusive, the
definition of the emissions to be included is essentially the same as
the previous definition. Ozone season day emissions means an average
day's emissions for a typical ozone season work weekday as defined in
CAA section 51.1100(cc). The state will select, subject to EPA
approval, the particular month(s) in the ozone season and the day(s) in
the work week to be represented. The selection of days should be
coordinated with the conditions assumed in the development of RFP plans
and/or emissions budgets for transportation conformity to allow
comparability of daily emissions estimates. The days should represent
the conditions that contribute to high ozone that led to a
nonattainment designation.
    For all inventories submitted to the EPA for this rule, states must
use the reporting requirements of the AERR to determine which sources
are reported as point sources as well as the detail (i.e., data
elements) required for such inventories, with the exception of the
emissions values. The emissions values must be ozone season day
emissions rather than the AERR requirement for annual emissions for
both the base year inventory for the nonattainment area and the
periodic inventory.
    Inventories of partial-county nonattainment areas must match the
spatial extent of the nonattainment area to include only emissions
within the nonattainment area. The EPA acknowledges the challenges
associated with partial county inventories and has prepared an updated
draft of the emissions inventory guidance (see below) to provide
additional information for air agencies to use in preparing partial
county emissions. The base year inventory for the nonattainment area is
used as the baseline for RFP plans to achieve emissions reductions
within the nonattainment area. As explained more fully in section III.C
of this preamble, the EPA has determined that emissions reductions in
areas outside the nonattainment area cannot be included in the area's
RFP demonstration. Thus, the EPA has concluded that for nonattainment
areas with partial county boundaries, all inventories must be developed
to reflect the partial county boundaries. This requirement partly
supersedes the requirement to use the AERR data elements, such that for
nonpoint and mobile sources, the county field required by the AERR
should be replaced by a separate identifier to indicate the partial
county nonattainment area. Because of this partial difference in
requirements, periodic inventories for partial county nonattainment
areas cannot be reported to the EPA as part of a state's AERR/NEI
triennial inventory submission. Instead, states must make available the
inventory data to the EPA as electronic files in some other electronic
media, such as FTP, zip drives, or DVDs.
    For all inventories that are used in developing RFP plans or
attainment demonstrations, mobile source emissions should be estimated
using the latest emissions models, data and planning assumptions
available at the time the SIP is developed. The latest approved models
should be used to estimate emissions from on-road and non-road sources,
in combination with the latest available estimates of vehicle miles
traveled (VMT), vehicle population, and/or equipment activity. States
are advised to check the EPA Web pages for the currently approved
mobile source models and to consult with the EPA Office of
Transportation and Air Quality and their Regional Office to determine
the versions of models to use for their SIPs for the 2008 ozone NAAQS.
For on-road mobile emissions in states other than California, the
current approved version of MOVES, as well as links to the Federal
Register Notice approving that version, and links to guidance documents
with much more detail on when and how MOVES should be used can be found
at: http://www.epa.gov/otaq/models/moves/index.htm. For California,
consult with the EPA Region 9 Office for the information on the latest
approved version of the EMFAC (EMissions FACtors) model. Emissions from
non-road equipment should be estimated with the latest official version
of the EPA's NONROAD model, and other appropriate methods for
estimating emissions from sources not covered by these models. Links to
Federal Register notices and policy guidance memos on the latest
approved versions of MOVES and NONROAD can be found at  http://www.epa.gov/otaq/models.htm.
    Additional information is available to states for all emissions
sources and quality assurance in the form of guidance. States should
consult the latest version of the guidance document ``Emission
Inventory Guidance for Implementation of Ozone and Particulate Matter
National Ambient Air Quality Standards (NAAQS) and Regional Haze
Regulations,'' EPA-454/R-05-001 (latest final November 2005; revised
draft April 2014) and any subsequent updates to that guidance that the
EPA makes available (which can be found at http://www.epa.gov/ttn/chief/eidocs/eiguid/index.html). States should submit inventories that
are appropriate for each nonattainment area and consistent with the
EPA's guidance.
    As indicated previously, some inventories submitted to meet the
requirements of CAA sections 182(a)(1) and 182(a)(3)(A) may be used in
the development of RFP plans and/or attainment demonstrations. The EPA
expects that the base year inventory for the nonattainment area will
serve as the RFP plan baseline. As such, the EPA requires the
methodologies used to develop these inventories to be clearly
documented and the inventories themselves to be subject to public
participation requirements and formal approval/disapproval by the
EPA.\60\
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    \60\ In comparison, the AERR emissions data are submitted by the
states to the EPA, electronically via the Emission Inventory System
to the National Emissions Inventory (NEI), and public review is not
required for NEI purposes. The states submit data to the NEI
inventory 12 months after the NEI inventory year (i.e., calendar
year 2011 NEI inventory data were to be submitted by December 31,
2012). The NEI process provides for the states to review the data as
collected by the EPA before the EPA officially publishes the data.
Under the current process, the EPA intends to publish the data 6
months after the AERR data are required to be submitted to the EPA.

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    The EPA is not finalizing the proposed approach, where we advised
that states could follow our existing September 29, 1992, guidance,
titled, ``Public Hearing Requirements for 1990 Base-Year Emissions
Inventories for Ozone and Carbon Monoxide Nonattainment Areas'' in
implementing certain SIP adoption and submission procedures for the
emissions inventory requirements under CAA sections 182(a)(1) and
182(a)(3)(A) for purposes of the 2008 ozone NAAQS. In that guidance,
the EPA indicated it could provide states with a time-limited ``de
minimis'' deferral of the CAA's state public hearing requirement for
the emissions inventory SIP revision required to be submitted for each
nonattainment area within 2 years of the date of designation. The EPA
continues to believe that there are valid policy reasons to provide
such a deferral since the inventories alone do not have significant
regulatory context without the accompanying area-specific RFP plans or
attainment plans, which are not required to be submitted until the 3rd
year after designations at the earliest. However, as a general matter
the CAA clearly requires that SIP submittals, including emissions
inventories (see CAA sections 182(a)(1) and 182(a)(3)(A)), must meet
the requirements of CAA section 110(a)(2), which includes the
requirement that the state provide reasonable notice and public hearing
for SIP submittals. As there is nothing in these CAA provisions that
provides for waiver or delay of the public notification and hearing
requirements specified in CAA section 110(a) de minimis or otherwise,
we no longer believe it is appropriate to advise states to follow the
1992 guidance. We instead remind states that the EPA's implementing
regulations at 40 CFR part 51 (Requirements for Preparation, Adoption,
and Submittal of Implementation Plans) provide flexibility for states
to streamline SIP-related public notification and hearing procedures
(for example, only holding a public hearing if one is requested, per 40
CFR 51.102), and we encourage states to take advantage of those
provisions in meeting the emissions inventory requirements under CAA
sections 182(a)(1) and 182(a)(3)(A).
c. Comments and Responses
    Commenters provided a variety of comments on issues relating to
emissions inventories. A full accounting of those comments and the
EPA's detailed responses are further explained in the Response to
Comments document contained in the docket. Significant comments were
made that resulted in small changes from the proposed rule. In
particular, commenters noted that the proposed rule failed to clearly
indicate the need for seasonal or summer day emissions values in the
required inventories and for use in the RFP plan. Different commenters
suggested different terms, time periods, and emissions bases to use in
the inventories and plans, including summer day, typical summer day,
high ozone season day, and maximum daily. These comments and others
noted the discrepancy with this rule and proposed changes to the AERR,
in that seasonal emissions were not expressly required by either the
proposed ozone requirements rule or the proposed AERR changes. As a
result of these comments, the EPA has included the requirement in this
rule as a logical outgrowth for ozone season day emissions, as defined
in this final rule, to be used in emission inventories submitted for
ozone SIPs. One commenter noted that partial county areas are not
expressly addressed in the emissions inventory requirements and pointed
out that it will be burdensome for states to create partial county
inventories. The EPA addresses partial county emissions in this final
rule by specifically defining the emissions to be included as ``within
the boundaries of the nonattainment area'' and clarifies in this
preamble that such partial county estimates are still needed to comply
with the CAA requirements for inventories and RFP plans.
2. Source Emission Statements
    States must develop emission reporting programs, called emission
statement programs, for VOC and NOX sources in accordance
with CAA section 182(a)(3)(B). The required state program and
associated regulation defines how states obtain emissions data directly
from facilities and report it to the EPA. States should coordinate
their emission statement regulations with the requirements laid out in
this rule, which includes coordination with requirements of the AERR.
    The EPA published guidance on source emission statements in a July
1992 memorandum titled, ``Guidance on the Implementation of an Emission
Statement Program.'' A memorandum titled, ``Emission Statement
Requirements Under 8-hour Ozone NAAQS Implementation,'' dated March 14,
2006, clarified that the source emission statement requirement under
the CAA was applicable to all areas designated nonattainment for the
1997 ozone NAAQS and classified as Marginal or higher under subpart 2,
part D, title I of the CAA. This requirement similarly applies to all
areas designated nonattainment for the 2008 ozone NAAQS. Most areas
that need an emission statement program already have one in place due
to a nonattainment designation for an earlier ozone NAAQS. If an area
has a previously approved emission statement rule in force for the 1997
ozone NAAQS or the 1-hour ozone NAAQS that covers all portions of the
nonattainment area for the 2008 ozone NAAQS, such rule should be
sufficient for purposes of the emissions statement requirement for the
2008 ozone NAAQS. The state should review the existing rule to ensure
it is adequate and, if it is, may rely on it to meet the emission
statement requirement for the 2008 ozone NAAQS. In cases when an
existing emission statement requirement is still adequate to meet the
requirements of this rule, states can provide the rationale for that
determination to the EPA in a written statement in the SIP to meet this
requirement. States should identify the various requirements and how
each is met by the existing emission statement program. In cases when
an emission statement requirement is modified for any reason, states
must provide the revisions to the emission statement as part of their
SIP.

K. What are the ambient monitoring requirements?

    The EPA's ambient monitoring requirements are contained in 40 CFR
part 58. Monitoring rule amendments published on October 17, 2006, (71
FR 61236) established minimum ozone monitoring requirements based on
population and levels of ozone in an area to better prioritize
monitoring resources. The minimum monitoring requirements are contained
in Table D-2 of Appendix D to part 58. The Photochemical Assessment
Monitoring Station (PAMS) program, required by CAA section 182(c)(1),
collects enhanced ambient air measurements in ozone nonattainment areas
classified as Serious, Severe, or Extreme. The monitoring rule
amendments published on October 17, 2006, reduced the minimum PAMS
requirements. The revisions were intended to require the retention of
the minimum common PAMS network elements necessary to meet the
objectives of every PAMS program, while freeing up resources for states
to tailor other features of their own PAMS networks to suit their
specific data needs. This final rule makes no changes to these existing
requirements.

L. How can an area qualify for a 1-year attainment deadline extension?

1. Summary of the Proposal
    Section 181(a)(5) of the CAA addresses the conditions under which
an area may be eligible for a 1-year extension of its attainment date.
Because that statutory provision was written for an exceedance-based
standard, such as the 1-hour ozone NAAQS, the EPA established through
the Phase 1 Rule (40 CFR 51.907) an interpretation that would apply to
a concentration-based standard, such as the 1997 ozone NAAQS.\61\ We
proposed the same approach as set forth in 40 CFR 51.907 for purposes
of the 2008 ozone NAAQS, which like the 1997 ozone NAAQS is a
concentration-based standard.
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    \61\ The exceedance based standard basically allowed the NAAQS
level to be exceeded an average of only once a year over a 3-year
period. (This is a generalization of how attainment is determined;
the actual method considers other factors such as completeness of
the data.) See 40 CFR, appendix H. In contrast, the concentration
based standard allows the level of the 8-hour ozone NAAQS to be
``exceeded'' more than once a year on average because the form
(concentration-based) of that NAAQS is determined by averaging the
4th highest reading for each year over a 3-year period.
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2. Final Action
    The EPA is finalizing the proposed approach. An area that fails to
attain the 2008 ozone NAAQS by its attainment date would be eligible
for the first 1-year extension if, for the attainment year, the area's
4th highest daily maximum 8-hour average is at or below the level of
the standard. The area would be eligible for the second 1-year
extension if the area's 4th highest daily maximum 8-hour value,
averaged over both the original attainment year and the first extension
year, is at or below the level of the standard. Thus, to be eligible
for the first 1-year extension, the 4th highest daily maximum 8-hour
value for an area would need to be at or below 0.075 ppm. The area
would be eligible for the second extension if the area's 4th highest
daily maximum 8-hour value, averaged over both the original attainment
year and the first extension year, is less than or equal to 0.075 ppm.
3. Rationale
    This approach is the same approach used for implementing the 1997
ozone NAAQS. The EPA believes this approach makes sense for the 2008
ozone NAAQS as well.
4. Comments and Responses
    The EPA received no adverse comments on the proposed action.

M. How will the EPA identify whether a potential rural transport
nonattainment area is adjacent to an urban area?

1. Summary of Proposal
    The CAA Amendments of 1990 contained section 182(h) that provides a
``rural transport'' determination for ozone nonattainment areas that
are rural in nature and can demonstrate that sources in the area do not
make a significant contribution to ozone concentrations measured in the
area or in other areas. These areas are subject to Marginal
nonattainment area requirements, regardless of the area's
classification under CAA section 181(a). This distinction was created
for rural nonattainment areas whose ozone problem is the result of
ozone and/or precursors transport into the area that is so overwhelming
that the contribution of local emissions to ozone concentrations above
the level of the NAAQS is relatively minor and that emissions within
the area do not significantly contribute to ozone measured in other
areas.
    One qualifying consideration for a rural transport area
determination is the lack of adjacency of the candidate nonattainment
area's boundary to potentially nearby urban areas. In general, we would
expect a rural nonattainment area that has few or insignificant sources
of ozone precursors, yet has a monitor indicating a violation of the
NAAQS, to encompass a relatively small geographic area due to the
relative lack of emissions sources.\62\ The rural transport area
criteria in CAA section 182(h) restrict rural transport areas to those
nonattainment areas that do not include and are not adjacent to any
part of a ``Metropolitan Statistical Area'' (MSA) or ``Consolidated
Metropolitan Statistical Area'' (CMSA) as defined by the U.S. Bureau of
the Census. In 2000, OMB issued new standards \63\ for defining
statistical areas to replace the pre-existing MSA and CMSA definitions
(65 FR 82228; December 27, 2000). Under the 2000 standards, MSAs are
defined as having a central county or counties with an urbanized area
of at least 50,000 people, plus adjacent outlying counties having a
high degree of economic integration with the central county, as
measured through worker commuting ties. Multiple counties are included
in a MSA if at least 25 percent of employed residents in the central
county commute to work in one or more adjacent counties. The term CMSA
was retired in 2003 with the introduction of Core Based Statistical
Area concepts. We proposed to interpret the references to both MSA and
CMSA in CAA section 182(h) to refer to the new Census Bureau definition
for the term MSA.
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    \62\ Nonattainment area boundaries are determined by the
Administrator during the area designations process governed by CAA
section 107(d), and must encompass the area that does not meet the
NAAQS as well as any nearby area that contributes to poor air
quality in the area that does not meet the NAAQS. While the lack of
emissions sources in a rural transport nonattainment area
foreshadows a relatively small area boundary, it may also signal
special challenges in complying with certain nonattainment area
requirements, including conformity for federal projects and new
source emissions offsets. States may wish to consider these
challenges in making nonattainment boundary recommendations to the
EPA for rural areas during the designations process.
    \63\ See http://www.census.gov/population/www/metroareas/metrodef.html.
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2. Final Action and Rationale
    We are finalizing, as proposed, the interpretation of the
references to both MSA and CMSA in CAA section 182(h) to refer to OMB's
current definition of MSA. Accordingly, to qualify as a rural transport
nonattainment area, the nonattainment area's boundary could not include
or be adjacent to a current OMB-defined MSA. Under this approach, any
nonattainment area associated with a Census-defined micropolitan area
(areas with central county or counties containing an urban cluster of
10,000-49,999 people plus adjacent counties having a high degree of
economic and social integration as measured through worker commuting)
or an area too sparsely populated to be included in a census-defined
statistical area, may be able to qualify as a rural transport
nonattainment area.\64\ An area seeking to be classified as a rural
transport nonattainment area would also need to meet the other criteria
specified in CAA section 182(h).
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    \64\ During the designations process for the 2008 ozone NAAQS,
the EPA did not identify any nonattainment areas as rural transport
areas.
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    The EPA believes this interpretation of CAA section 182(h) is
consistent with the original scope of CAA section 182(h) as promulgated
in 1990 and provides maximum flexibility for areas to qualify for this
determination where appropriate. We did not receive any adverse
comments on our proposed interpretation.

N. What are the special requirements for multi-state nonattainment
areas?

    Each state within a multi-state ozone nonattainment area is
responsible for meeting all the requirements relevant to that area. CAA
section 182(j)(1)(A) requires that states should ``take all reasonable
steps to coordinate substantively and procedurally'' on SIP
development. States should coordinate

on topics such as determining the appropriate modeling domain, baseline
year, projection years and meteorological episodes. In addition, they
should coordinate modeling efforts and, as required by CAA section
182(j)(1)(B), the attainment demonstration must be based on
photochemical grid modeling or another method determined by the EPA to
be at least as effective.
    CAA section 182(j)(2) recognizes that in certain instances, one or
more states within a multi-state nonattainment area may not submit an
attainment plan by the required date, thus interfering with the ability
of the area as a whole to demonstrate attainment. In such case, CAA
section 182(j) provides that even though the area as a whole would not
be able to demonstrate attainment, the sanction provisions of CAA
section 179 shall not apply in the portion of the nonattainment area
located in a state that submitted all other provisions of an attainment
plan and demonstrated that it could have demonstrated attainment but
for the failure of the other state to cooperate. The EPA did not
propose any changes to its prior interpretations of these sections of
the CAA (See 70 FR 71612), and no comments were received on these
provisions. Therefore, these interpretations will continue to apply for
purposes of the 2008 ozone NAAQS.

O. How will the EPA address interstate and international ozone
transport?

1. Interstate Transport
    The EPA recognizes that many states are affected by transported
ozone and ozone precursors from upwind states, and that transported
pollution may contribute significantly to air pollution that exceeds
the NAAQS in those states. The CAA establishes states' responsibilities
to address interstate transport through two provisions. First, CAA
section 110(a)(2)(D)(i) obligates states to include provisions in their
infrastructure SIPs to prohibit any source or other type of emissions
activity in one state from contributing significantly to nonattainment,
or interfering with maintenance, of the NAAQS in another state, from
interfering with required provisions preventing significant
deterioration of air quality or from interfering with measures to
protect visibility in another state. Second, CAA section 126 directs
states to include provisions to establish a notification process in
their infrastructure SIPs through which downwind jurisdictions can be
alerted to specific sources of transported pollution. The EPA issued
its ``Guidance on Infrastructure State Implementation Plan Elements
Under the Clean Air Act Sections 110(a)(1) and 110(a)(2),'' on
September 13, 2013,\65\ on the required elements of the CAA section 110
infrastructure SIP submittal for the 2008 ozone NAAQS. This guidance
does not, however, address the requirements of CAA section
110(a)(2)(D)(i). The proposal for this rulemaking, and this final rule,
also do not address these requirements relating to transport. The EPA
will address the transport requirements in a separate action.
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    \65\ See http://www.epa.gov/oar/urbanair/sipstatus/infrastructure.html.
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    Where interstate transported emissions contribute to an exceedance
or violation and come from prescribed fire, wildfires or other natural
sources, air agencies may be able to use the provisions in the EPA's
Exceptional Events Rule (40 CFR 50.14) to request exclusion of affected
data. Once EPA concurs with an air agency's request, the event-
influenced data are officially noted and removed from the data set used
to calculate official design values.
    Because of previously expressed stakeholder feedback regarding
implementation of the Exceptional Events Rule and specific stakeholder
concerns regarding the analyses that can be used to support ozone-
related exceptional event demonstrations, the EPA intends to propose
revisions to the Exceptional Events Rule in a future notice and comment
rulemaking effort and will solicit public comment at that time.
Additionally, the EPA intends to develop guidance to address
implementing the Exceptional Events Rule criteria for wildfires that
could affect ambient ozone concentrations. Depending on the nature and
scope of interstate emission events affecting downward air quality, the
EPA may be able to assist states in developing approvable exceptional
events demonstrations.
2. International Transport
    Most ozone air quality problems in the United States are due
primarily to emission sources within the United States. However,
domestic ozone air quality can also be affected by sources of emissions
located across United States borders in Canada and Mexico, and from
other continents. These contributions to U.S. ozone concentrations from
sources outside of the United States can affect to varying degrees the
ability of some areas to attain and maintain the 2008 ozone NAAQS. The
EPA will continue to work with our domestic and international partners
to better understand the extent and implications of transboundary flows
of air pollutants and, where possible, to mitigate their impact on U.S.
domestic air quality.
a. Summary of the Proposal
    Section 179B of the CAA allows the EPA to approve an attainment
demonstration for a nonattainment area if: (1) The attainment
demonstration meets all other applicable requirements of the CAA; and
(2) the submitting state can satisfactorily demonstrate that ``but for
emissions emanating from outside of the United States,'' the area would
attain and maintain the ozone standard. The EPA proposed that this
could include consideration of any emissions from North American or
intercontinental sources.
b. Final Action and Rationale
    The EPA is finalizing this action as proposed. The EPA believes
that the best approach for addressing the potential impacts of
international transport on nonattainment is for states to work with the
relevant EPA Regional Office on a case-by-case basis to determine the
most appropriate information and analytical methods for each area's
unique situation. We will work with states that are developing plans
pursuant to CAA section 179B, and ensure the states have the benefit of
the EPA's developing understanding of international transport of ozone
and its precursors.
    Although monitored data cannot be excluded for a determination of
whether an area has attained a NAAQS based solely on the fact the data
are affected by emissions from outside the U.S., such data may be
excluded from consideration if they were significantly influenced by
exceptional events as described in CAA section 319(b). Where
international transport meets the criteria and procedural requirements
contained in the EPA's Exceptional Events Rule (40 CFR 50.14), it may
be addressed by that rule.\66\ Depending on the nature and scope of
international emission events affecting air quality in the U.S., the
EPA may be able to assist states in developing approvable exceptional
events demonstrations.
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    \66\ ``Treatment of Data Influenced by Exceptional Events; Final
Rule'' (72 FR 13560, March 22, 2007).
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c. Comments and Responses
    Comment: One commenter supported the EPA's interpretation of CAA
section 179B to include consideration of any emissions from any non-
United States source and requested confirmation that the EPA's
interpretation may be applied to areas other than those adjoining

international borders. The commenter believed that CAA section 179B
does not limit this option to areas, regardless of classification and
believed that the EPA did not provide an explanation for why it
proposed limiting the availability of a determination under CAA section
179B for Marginal classified areas.
    Response: The EPA appreciates the commenter's support. The EPA has
interpreted the Act such that CAA section 179B allows the EPA to
approve an attainment demonstration if the state can satisfactorily
demonstrate that ``but for emissions emanating from outside of the
United States,'' the area would attain and maintain the ozone standard.
The EPA has historically evaluated these demonstrations on a case-by-
case basis, based on the individual circumstances. The EPA does not
believe this provision is restricted to areas adjoining international
borders. Also, in the proposal the EPA indicated that for areas
classified as Moderate and above, the modeling and other elements of
the attainment demonstration must show timely attainment of the NAAQS
but for the emissions from outside of the U.S. However, if a Marginal
area (which is not otherwise required to submit an attainment
demonstration) were to submit to the EPA a demonstration that they
could attain the standard but for international emissions, the EPA
would be able to evaluate that demonstration similarly to
demonstrations submitted by higher classified areas.

P. How will the CAA section 182(f) NOX provisions be handled?

1. Summary of the Proposal
    We proposed, consistent with the approach taken in the Phase 2 Rule
for the 1997 ozone NAAQS and the 2005 updated guidance, that a
previously granted NOX exemption (or waiver) under the 1-
hour or 1997 ozone NAAQS would not automatically apply for purposes of
implementing the 2008 ozone NAAQS.
2. Final Action and Rationale
    We are finalizing this approach as proposed. A state with a
previously approved NOX waiver for the 1-hour or 1997 ozone
NAAQS would need to submit a new request for an exemption that is
supported by analyses specific to the 2008 ozone NAAQS. The new request
should consider any relevant information developed after the 1-hour or
1997 8-hour ozone NAAQS waivers were granted.
    The EPA believes that while it may be appropriate in certain
circumstances to grant NOX waivers, these waivers should be
based upon applications and analyses specifically focused on the
circumstances relevant for attainment of the 2008 ozone NAAQS, rather
than a previous ozone NAAQS, since the standards for granting a waiver
relate to attainment of the relevant NAAQS.
    As states evaluate whether to seek a NOX waiver, the EPA
encourages them to include consideration of air quality effects that
may extend beyond the designated nonattainment area. A petition
requesting a NOX exemption for the 2008 ozone NAAQS must
contain adequate documentation that the provisions of CAA section
182(f), some of which relate to attainment impacts in other areas, are
met. The January 14, 2005 memo \67\ provides guidance on appropriate
documentation for a waiver request for application to the 8-hour ozone
program. The EPA believes this guidance is sufficient to cover the 2008
ozone NAAQS.
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    \67\ Memorandum dated January 14, 2005, ``Guidance on Limiting
Nitrogen Oxides (NOX) Requirements Related to 8-Hour
Ozone Implementation'' from Stephen D. Page, Director, Office of Air
Quality Planning and Standards, to Air Directors, Regions I-X.
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3. Comments and Responses
    Comment: One commenter stated that the EPA should avoid granting
NOX exemptions for nonattainment areas that use
NOX controls from other programs to demonstrate attainment
and/or to address other provisions of the CAA.
    Response: In order to request a NOX exemption, a state
must submit a petition specific to the 2008 ozone NAAQS. This petition
must specifically address the provisions of CAA section 182(f). The EPA
will grant NOX exemptions only through notice-and-comment
rulemaking where the public will have an opportunity to address whether
the petition complies with the provisions of CAA section 182(f). In
granting waivers, the EPA will take into consideration existing
NOX controls in an area.

Q. Emissions Reduction Benefits of Energy Efficiency/Renewable Energy
Policies and Programs, Land Use Planning and Travel Efficiency

1. Energy Efficiency/Renewable Energy Policies and Programs
    Energy efficiency and renewable energy (EE/RE) policies and
programs are adopted by federal, state and local governments to lower
energy demand through the use of more energy efficient equipment,
technologies and practices and to transition to cleaner energy. These
policies help reduce electricity generation from fossil-fueled sources,
which, in turn, can result in lower emissions of NOX (as
well as other criteria pollutants, hazardous air pollutants and
greenhouse gases). Energy efficiency policies offer cost savings
benefits, and can be a cost-effective strategy to help achieve air
quality goals. The EPA encourages state adoption of these policies and
programs to benefit nonattainment areas and to reduce the impact of
ozone transport on downwind areas.
    In July 2012, the EPA released the ``Roadmap for Incorporating
Energy Efficiency/Renewable Energy Policies and Programs into State and
Tribal Implementation Plans (SIPs/TIPs)'' \68\ to clarify guidance on
the incorporation of EE/RE measures in SIPs/TIPs. The Roadmap is a
``living'' document that will be updated periodically as new
information becomes available. The Roadmap describes four pathways that
states can use for considering air pollution reductions from EE/RE
policies and programs in SIPs and TIPs. Valid EE/RE policies and
programs that meet the applicable requirements of CAA section 182(c)(9)
can also be used as contingency measures.
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    \68\ See http://www.epa.gov/airquality/eere.html.
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    In addition to the Roadmap, the EPA is providing training and
technical assistance to state, tribal and local agencies, as well as
tools for quantifying the emissions impacts of EE/RE policies and
programs (i.e., the AVoided Emissions genERation Tool, AVERT),\69\ and
energy savings information for state-level EE policies and
programs.\70\ The EPA is also working with states to develop examples
that illustrate how reductions from specific EE/RE policies and
programs could be quantified and considered in SIPs.
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    \69\ See http://epa.gov/avert/.
    \70\ See http://www.epa.gov/statelocalclimate/state/topics/energy-efficiency.html.
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2. Land Use Planning
    States may also wish to consider strategies that foster more
efficient urban and regional development patterns as a long-term air
pollution control measure. Resources include the HUD DOT EPA
Sustainable Communities Partnership, as well as the policy and
technical guidance documents on land use available on the EPA's Office
of Transportation and Air Quality Web site.\71\ These documents provide
communities with the information they need to better understand the
link between air quality, transportation and land use activities, and
how certain land use activities have the potential to help local areas
achieve and maintain healthy air quality. The

documents also include methods to help communities account for the air
quality benefits of their local land use activities in their air
quality plans. If wildfire impacts are significant in a particular
area, air agencies and communities may be able to lessen the impacts of
wildfires by working collaboratively with land managers and land owners
to employ various mitigation measures including taking steps to
minimize fuel loading in areas vulnerable to fire. The EPA will provide
additional guidance as needed, and will continue to work with states on
incorporating these types of programs into their SIPs.
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    \71\ See http://www.epa.gov/otaq/stateresources/policy/pag_transp.htm.
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3. Travel Efficiency
    Areas may also consider incorporating travel efficiency strategies,
such as new or expanded mass transit options, commuter strategies,
system operations (e.g., eco-driving, ramp metering), pricing (e.g.,
parking taxes, congestion pricing, intercity tolls), speed limit
restrictions and multimodal freight strategies in their SIPs. In March
of 2011, the EPA released two documents that we believe will prove to
be useful to states that want to evaluate emissions reductions that may
be available from travel efficiency strategies. The first document is
titled, ``Potential Changes in Emissions Due To Improvements in Travel
Efficiency.'' This report provides information on the effectiveness of
travel efficiency measures for reducing emissions of NOX,
VOC and PM2.5 at the national scale. The second document is
titled, ``Transportation Control Measures: An Information Document for
Developing and Implementing Emission Reduction Programs.'' This
document provides information on transportation control measures that
have been implemented across the country for a variety of purposes,
including reducing emissions related to criteria pollutants. These
documents are available on the EPA's Office of Transportation and Air
Quality Web site.\72\
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    \72\ See http://www.epa.gov/otaq/stateresources/policy/pag_transp.htm.
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R. Efforts To Encourage a Multi-Pollutant Approach When Developing 2008
Ozone SIPs

1. Summary of the Proposal
    The EPA stated in the proposal that from a planning and resource
perspective, we believe it can be efficient for states to develop
integrated control strategies that address multiple pollutants rather
than separate strategies for each pollutant or NAAQS individually. The
EPA also provided states with recommendations and considerations to
take into account when developing a comprehensive approach. The EPA
requested comment on what incentives or assistance we might be able to
provide to encourage states to integrate their planning activities.
2. Final Action and Rationale
    From a planning and resource perspective, the EPA continues to
believe that multi-pollutant control strategy planning can be efficient
for states. An integrated air quality control strategy that reduces
multiple pollutants can help ensure that reductions are efficiently
achieved and produce the greatest overall air quality benefits.
However, multi-pollutant approaches are not required as part of this
rule.
    States may also find it desirable to assess the impact of ozone,
PM2.5 and/or regional haze control strategies on toxic air
pollutants regulated under the CAA or under state air toxics
initiatives. Given the relationships that exist between toxic air
pollutants and the formation of ozone and PM2.5, states and
sources may find that controls can be selected to meet goals for ozone
and/or PM2.5 attainment as well as those of specific toxic
air pollutant programs.
    We recommend that states and tribes wishing to take a comprehensive
approach consider the following activities:
     Choose or develop models for use in the attainment
demonstration that can assess the air quality and ecosystem impacts of
measures to reduce ozone precursors, secondary fine particles,
pollutants that contribute to regional haze and, where appropriate,
toxic air pollutants and other related pollutants that can impact
ecosystems.
     Conduct an integrated assessment of the impact controls
have on ambient levels of ozone, PM2.5, regional haze and,
where applicable, toxic air pollutants, greenhouse gases, ecosystem
protection and environmental justice considerations.
     Use common data bases and analytical tools, where
possible.
3. Comments and Responses
    Comment: Several commenters supported the use of a multi-pollutant
approach. One commenter encouraged the EPA to allow states to take
credit for programs that may not yet have been fully implemented.
Another commenter noted the constraints in the CAA, which focuses on a
pollutant-by-pollutant approach, and another commenter stated that they
prefer a single pollutant approach.
    Response: The EPA supports multi-pollutant planning, where
possible. Regarding the comment encouraging the EPA to allow states to
take credit for programs that may not yet have been fully implemented,
please see Section III.B in the preamble for details regarding the
EPA's final policy on this subject.
    The EPA also supports considering the co-benefits of emissions
reductions on multiple pollutants. We acknowledge that there are CAA
constraints that may limit the incentive for multi-pollutant planning,
and clarify that single-pollutant planning is acceptable under the Act.

S. What are the requirements for the OTR?

    The EPA proposed to adopt for the 2008 ozone NAAQS the same
requirements applicable to the OTR that were codified in 40 CFR 51.916
for the 1997 ozone NAAQS, except that the submission date for OTR RACT
SIPs required under CAA section 182(b)(2) would be the same as provided
under the RACT section of this regulation for nonattainment areas. (See
Section III.A of this preamble for additional information on SIP
submittal timeframes.) We are finalizing adoption of the requirements
as proposed along with the OTR RACT SIP submittal due date.

T. Are there any additional requirements related to enforcement and
compliance?

    The EPA did not propose any specific regulatory provisions related
to compliance and enforcement. CAA section 172(c)(6) requires
nonattainment SIPs to ``include enforceable emission limitations, and
such other control measures, means or techniques . . . as well as
schedules and timetables for compliance, as may be necessary or
appropriate to provide for attainment . . .'' The EPA's current
guidance, ``Guidance on Preparing Enforceable Regulations and
Compliance Programs for the 15 Percent Rate-of-Progress Plans (EPA-452/
R-93-005, June 1993)'' is still relevant to rules adopted for SIPs
under the 2008 ozone NAAQS and should be consulted for purposes of
developing appropriate enforceable nonattainment plan provisions under
CAA section 172(c)(6). The EPA did not solicit comment on this section
and thus, none were received.

U. What are the requirements for addressing emergency episodes?

1. Summary of the Proposal
    The EPA proposed that the existing requirements for emergency
episodes (40 CFR part 51, subpart H) would also apply to the 2008 ozone
NAAQS.

2. Final Action and Rationale
    The EPA did not receive any adverse comments on the proposal. The
EPA is finalizing the requirements for emergency episodes as proposed.
The EPA believes the existing requirements for emergency episodes (40
CFR part 51, subpart H) remain appropriate for the 2008 ozone NAAQS
and/or any current ozone NAAQS. If wildfire is a potential contributor
to these episodes, the EPA urges implementing state and local agencies
to coordinate with the land management agencies, as appropriate, in
developing plans and appropriate public communications regarding public
safety and reducing exposure.

V. How does the ``Clean Data Policy'' apply to the 2008 ozone NAAQS?

1. Summary of the Proposal
    The EPA proposed to apply the same approach with respect to the
Clean Data Policy for the 2008 ozone NAAQS as it applied in the Phase 1
Rule for the 1997 ozone NAAQS. That is, a determination of attainment
would suspend the obligation to submit attainment planning SIP elements
for the 2008 ozone NAAQS. Such a determination would suspend the
obligation to submit any attainment-related SIP elements not yet
approved in the SIP, for so long as the area continues to attain the
2008 ozone NAAQS.
2. Final Action
    The EPA is finalizing this action as proposed. The EPA is replacing
40 CFR 51.918 with 40 CFR 51.1118 to consolidate in one regulation a
comprehensive provision applicable to determinations of attainment for
the current and former ozone NAAQS. Thus, 40 CFR 51.1118 will apply to
a determination of attainment that is made with respect to any revoked
or current ozone NAAQS--the 1-hour, the 1997 or the 2008 ozone NAAQS.
3. Rationale
    The EPA continues to believe that it is appropriate for an area
that has met an ozone NAAQS to suspend further attainment planning
efforts for that ozone NAAQS. The new 40 CFR 51.1118 sets forth the
regulatory consequences of an EPA determination, made after notice-and-
comment rulemaking, that an area designated nonattainment for an ozone
standard has air quality attaining that standard. Upon such a
determination by the EPA, the requirements for the area to submit an
attainment demonstration, associated reasonably available control
measures, RFP plans, contingency measures and other attainment-related
planning requirements for that NAAQS, shall be suspended until such
time as the area is redesignated to attainment, at which time the
requirements no longer apply, or until the EPA determines that the area
has again violated that ozone NAAQS, in which case the requirements are
again applicable.
4. Comments and Responses
    Comment: Several commenters supported the continued use of the
Clean Data Policy. One of these commenters requested that the EPA
expeditiously redesignate areas using its CAA section 107(d)(3)
authority for states that have submitted ``clean data'' certification
and redesignation/maintenance SIPs.
    Response: As stated in the policy, the requirements for an
attainment demonstration, RFP and contingency measures are designed to
bring an area into attainment. Once this goal has been achieved, we
believe the statute no longer requires submission of plans designed to
bring the area into attainment and thus it is appropriate to suspend
the obligation that states submit plans to meet that goal, so long as
the area continues to attain the relevant standard. The EPA Regional
Offices will act on redesignating areas based on any CAA section 175A
submittals that were received in as expeditious a manner as possible.

W. How does this final rule apply to tribes?

    As we mentioned in the proposal, tribes are generally not required
to submit tribal implementation plans (TIPs).\73\ However, should a
tribe choose to develop a TIP, this final rule is intended to serve as
a guide for addressing key implementation issues for their area of
Indian country. This rule will likely be especially useful to those
tribes whose areas of Indian country were designated as separate
nonattainment areas from surrounding state areas.
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    \73\ On January 17, 2014, the United States Court of Appeals for
the District of Columbia Circuit issued a decision vacating the
EPA's 2011 rule titled ``Review of New Sources and Modifications in
Indian Country'' (76 FR 38748) with respect to non-reservation areas
of Indian country (See, Oklahoma Department of Environmental Quality
v. EPA, 740 F.3d 185 (D.C. Cir. 2014)). Under the court's reasoning,
with respect to CAA SIPs, a state has primary regulatory
jurisdiction in non-reservation areas of Indian country (i.e.,
Indian allotments located outside of reservations and dependent
Indian communities) within its geographic boundaries unless the EPA
or a tribe has demonstrated that a tribe has jurisdiction over a
particular area of non-reservation Indian country within the state.
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X. What collaborative program has the EPA implemented for the 2008
ozone NAAQS?

    The EPA stands ready to assist states in implementing the 2008
ozone NAAQS. The Ozone Advance program, which began in April 2012, is
an opportunity for 2008 ozone NAAQS attainment areas to work
collaboratively with EPA to improve local air quality. Information on
the Ozone Advance program for the 2008 ozone NAAQS is provided in a
separate guidance document that is available at http://www.epa.gov/ozonepmadvance.

IV. What are the anti-backsliding requirements for the revoked 1997
ozone NAAQS?

A. What is the effective date of the revocation of the 1997 ozone
NAAQS?

1. Summary of the Proposal