stationary source emissions monitoring and any other methodologies--
complete with equations and explanations--for estimating emissions
reductions due to improved monitoring.
2. Final Rule
    The EPA did not propose any specific changes to source monitoring
requirements for PM2.5 and is therefore not finalizing any
specific requirements, beyond what is required elsewhere in the final
rule.
3. Comments and Responses
    Comment. Several commenters focused on critiquing PM CEMS, PM CPMS
and BLDS technology and claim that improved monitoring changes the
stringency of existing rules and requires rulemaking. The commenters
provided no examples or specific information in response to the request
for information.
    Response. We appreciate the information submitted by the
commenters, but we are not responding to the comments here because they
are not directly pertinent to the rule being finalized. The EPA will
continue to explore and implement innovative, cost-effective ideas that
offer tangible incentives for improved source monitoring to be adopted
as part of the associated emissions limitations that will help achieve
additional reductions from stationary sources and bring areas into
attainment for the PM2.5 NAAQS in a timely way. See the
response to comments document for more detailed information.

K. Stationary Source Test Methods for Emissions of Condensable PM2.5

1. Summary of Proposal
    As discussed in the proposal, direct PM2.5 is comprised
of two components: Filterable PM2.5 and condensable
PM2.5 emissions. Accurate test methods for condensable
PM2.5 emissions have only been recently developed and
approved by the EPA, and in the proposal the EPA explained that use of
these test methods, including methods to quantify condensable
PM2.5 emissions, were essential for identifying sources of
direct PM2.5 emissions which, if better controlled, can help
to bring a PM2.5 nonattainment area into attainment.
However, the EPA did not propose any changes to those test methods.
    The EPA did propose to require that, where a state needs to adopt
new or revised control measures for direct PM2.5 from
sources in a nonattainment area, the state must specify
PM2.5 emission limits in its SIP that include both
filterable and condensable emissions. In addition, compliance testing
of those sources must include measurement of condensable emissions
(such as through the use of Method 202). The EPA proposed that any new
or revised emission limit used as a control measure to bring an area
into attainment for any current or future PM2.5 NAAQS must
use methods that measure PM2.5 or total PM including both
filterable and condensable particulate matter.
    The 2007 PM2.5 Implementation Rule required, beginning
on January 1, 2011, that states take into consideration condensable
PM2.5 emissions when establishing emission limits for
stationary sources as part of any control strategy for PM2.5
NAAQS nonattainment areas.\274\ This date coincided with the effective
date of the agency's revisions to test methods for measuring filterable
PM10 emissions from stationary sources (Method 201A) and for
measuring condensable PM emissions from stationary sources (Method
202).\275\ The revisions to those test methods added procedures to
measure PM2.5 filterable and condensable particulate
material and increased the precision of Method 202 and improved the
consistency in the measurements obtained between source tests performed
under different regulatory authorities.
---------------------------------------------------------------------------

    \274\ 72 FR 20586 (April 25, 2007).
    \275\ 75 FR 80118 (December 21, 2010).
---------------------------------------------------------------------------

    In the preamble to the 2007 PM2.5 Implementation Rule,
the EPA explained that the use of the (then anticipated) revisions to
the EPA Method 201A combined with Method 202 to obtain measured source
specific emissions of PM2.5 would improve the quality of
emissions inventories for stationary sources and would aid in the
development of a more reliable attainment strategy, as sources that may
have a considerable amount of condensable PM2.5 emissions
could be better characterized with the new methods.

2. Final Rule
    The EPA is finalizing the PM2.5 emissions limit and
testing requirement as proposed. For sources that are required to adopt
a new or revised direct PM2.5 emissions limit as part of the
attainment demonstration (including, but not limited to, for RACT,
BACT, or MSM), the state must specify PM2.5 emission limits
in its SIP that include both filterable and condensable emissions. In
addition, compliance testing requirements for those sources must
include both measurement of filterable and condensable emissions.
Existing filterable PM emission limitations that are not being revised
as part of a Moderate area or Serious area attainment plan can remain
expressed in terms of filterable PM and can rely on the existing test
method used by the state for compliance determination.
    The EPA continues to believe that using these improved test
methods, including methods to quantify condensable PM2.5
emissions, can help identify sources of direct PM2.5
emissions which, if better controlled, can help to bring a
PM2.5 nonattainment area into attainment. Likewise, use of
these test methods may help a state identify sources whose condensable
emissions may have been incorrectly estimated and therefore may not
provide meaningful PM2.5 control opportunities.
3. Comments and Responses
    Comment: Some commenters stated that the EPA should make clear that
as long as testing and monitoring is required for any new filterable
and/or condensable PM emission limitation imposed, testing for ``total
PM2.5'' is not required and the EPA should allow states
flexibility in determining the best way to demonstrate compliance with
any new emission limitations. The new emission limitation could take
the form either of a limitation on condensable PM2.5 or a
limitation on total direct PM2.5 emissions. The commenter
further stated the EPA should make clear that states that specify
condensable PM or total PM2.5 emission limitations are not
required to adopt Method 202 as the compliance test method.
    Response: In the final rule, the EPA is requiring new or revised
PM2.5 emissions limits and associated source testing to
account for condensable emissions, but the EPA is not imposing any
specific source testing requirements that would require total
PM2.5 testing or the use of a specific test method. The EPA
acknowledges that states have flexibility to determine the necessary
emissions limitations of PM2.5 to meet SIP requirements for
the NAAQS attainment. When states assess the contribution of the
filterable and condensable PM component to PM2.5 they may
require stationary source tests that include both filterable
PM2.5 and condensable particulate matter to ensure emission
limits are attained by subject facilities. Since we recognize that
primary PM2.5 emissions can be measured with the combination
of several promulgated test methods depending on the stationary source
emission temperature and moisture content, states have the flexibility
to require the appropriate filterable and condensable particulate
measurement methods based on source conditions.
    Comment: Some commenters agreed with the EPA's proposal not to
require consideration of condensable PM in any existing emission
limitations that are not otherwise being revised. The commenters stated
that no purpose would be served by requiring states to include
condensable PM in such standards if no revision is necessary to
demonstrate attainment. Other commenters objected to the EPA's proposal
to not require states to update all existing PM emission limitations to
include limitations on condensable PM. The commenters stated the EPA's
proposal is nonsensical and undermines any ability to demonstrate
compliance with the Act. The commenters stated that, by the EPA's own
admission, inventories that do not reflect measured condensables from
direct PM2.5 sources are not an ``accurate'' inventory of
``actual emissions.'' The commenters further stated that, similarly,
areas could not satisfy the criteria for RACM or BACM, or demonstrate
expeditious attainment if the existing state emission limitations are
not required to be updated to account for condensable emissions from
these sources.
    Response. The EPA agrees with the commenters who maintain that
existing PM2.5 emissions limits do not need to be revised to
include emissions limits for condensable PM for sources from which
additional emissions reductions are not needed in order to demonstrate
attainment. The EPA does not agree that all existing direct
PM2.5 emissions limits in the SIP have to include emissions
limits that account for or specifically address condensable PM. However
sources with new or revised PM2.5 emissions limits and
associated source testing must account for condensable emissions.
    If the state has submitted an attainment demonstration that
includes an adequate RACT, BACT, and/or MSM analysis, and has taken
into account all known emissions of filterable and condensable
PM2.5 in the area, then there is no need to require new
condensable PM2.5 emissions limits and testing for sources
that were not needed to be additionally controlled for attainment
purposes. The state may want to require additional condensable
PM2.5 emissions limits and testing to gain a better
understanding of the sources in the nonattainment area (especially for
sources which may be most likely to emit condensables). This could
provide additional information for future SIPs and control programs if
nonattainment persists. However, unless specific direct
PM2.5 emissions reductions are shown to be needed in order
for the area to attain the NAAQS, there does not need to be a SIP
requirement to include new condensable emissions limits and testing for
all existing sources with PM2.5 emissions limits.
    Additionally, the commenters stated that emissions inventories
would not be ``accurate'' and states could not satisfy their RACM/BACM
requirements if condensable emissions were not included in the SIP.
Regardless of emissions limits and source testing requirements,
quantification and reporting of filterable and condensable
PM2.5 emissions is required as part of the emissions
inventory and RACT/BACT rule requirements. In some cases, condensable
PM2.5 information is available from previous source testing.
In other cases, condensable PM2.5 emissions must be
estimated through the use of emissions factors that have been developed
from source testing of similar sources. States are therefore already
required to take into account both filterable and condensable emissions
as part of their inventory and control strategy (RACT/BACT)
development. See section IV.B of this preamble for more information on
emissions inventory requirements, section IV.D of this preamble for
more information on RACT requirements, and section VI.D of this
preamble for more information on BACT requirements.

X. Revocation of the 1997 Primary Annual PM2.5 NAAQS

A. Summary of the Proposal

    The EPA proposed two options for revoking the 1997 primary annual
PM2.5 NAAQS and sought comment on whether to revoke the
NAAQS at the current time.
    The two proposed options were:

     Option 1: Revoke the 1997 primary annual
PM2.5 NAAQS for all purposes in attainment areas for that
NAAQS 1 year after the effective date of the designations for the
2012 primary annual PM2.5 NAAQS; and
     Option 2: Revoke the 1997 primary annual
PM2.5 NAAQS for all purposes in all

nonattainment and attainment areas for that NAAQS 1 year after the
effective date of the designations for the 2012 primary annual
PM2.5 NAAQS.

    Under the first proposed option, the EPA would revoke the 1997
primary annual PM2.5 NAAQS for all purposes in areas that
are designated as attainment for that NAAQS 1 year after the effective
date of designations for the 2012 primary annual PM2.5
NAAQS, as well as in the future as additional areas are redesignated as
attainment areas after the initial revocation. The areas addressed by
this option are:

     Those that were originally designated as attainment
areas for the 1997 annual PM2.5 NAAQS; and
     those that were originally designated as nonattainment
but have since or will in the future be redesignated to attainment
for that NAAQS.

    Under this option, the EPA would not revoke the 1997 primary annual
PM2.5 NAAQS in any area as long as it is designated
nonattainment for that NAAQS. This option is consistent with the
approach established for the transition to the current lead and
SO2 NAAQS.
    Areas designated nonattainment for the 2012 primary annual
PM2.5 NAAQS would be required under Option 1 to comply with
applicable CAA requirements as set forth in the CAA. For transportation
conformity purposes, these requirements began to apply 1-year after the
effective date of designations and include using adequate or approved
SIP motor vehicle emissions budgets for the 1997 annual
PM2.5 NAAQS or the 2006 24-hour PM2.5 NAAQS where
they exist until the area has approved or adequate budgets for the 2012
primary annual PM2.5 NAAQS.\276\ Areas that have adequate or
approved motor vehicle emissions budgets for both the 1997 annual
PM2.5 NAAQS or the 2006 24-hour PM2.5 NAAQS
should refer to Question 3.3 in EPA's ``Implementing Transportation
Conformity Guidance for 2012 PM2.5 Nonattainment Areas'' for
additional information on which budgets to use in conformity
determinations prior to having adequate or approved budgets for the
2012 primary annual PM2.5 NAAQS.\277\ The use of such
budgets serves as the appropriate anti-backsliding measure for
transportation conformity purposes.
---------------------------------------------------------------------------

    \276\ Areas that do not have adequate or approved motor vehicle
emissions budgets for the 1997 annual PM2.5 NAAQS or the
2006 24-hour PM2.5 NAAQS would use one of the two interim
emissions tests required by 40 CFR 93.109(c)(3) and 40 CFR
93.119(b).
    \277\ The guidance is available at: http://www3.epa.gov/otaq/stateresources/transconf/documents/420b15091.pdf.
---------------------------------------------------------------------------

    Under the second proposed option, the EPA would revoke the 1997
primary annual PM2.5 NAAQS for all CAA purposes in all
nonattainment and attainment areas 1 year after the effective date of
designations for the 2012 primary annual PM2.5 NAAQS. The
requirements associated with revoking the 1997 primary annual
PM2.5 NAAQS in attainment areas for that NAAQS would be the
same as those that would apply under Option 1. However, revoking the
1997 primary annual PM2.5 NAAQS in nonattainment areas for
that NAAQS would require anti-backsliding measures for areas designated
nonattainment for the 1997 annual PM2.5 NAAQS at the time of
the revocation. For details on the proposed anti-backsliding measures,
refer to the discussion in the proposal for this final rule. (80 FR
15340)
    The EPA also requested comment on not revoking the 1997 primary
annual PM2.5 NAAQS at this time. For additional details on
all of the proposed options refer to the proposal. (80 FR 15340)
    The EPA did not propose to revoke the 1997 secondary annual
PM2.5 NAAQS in this action because that NAAQS has been
retained in order to prevent certain welfare effects associated with
PM2.5.\278\
---------------------------------------------------------------------------

    \278\ 78 FR 3086 (January 15, 2013).
---------------------------------------------------------------------------

    For details on past revocations of the NAAQS including the 1-hour
and 1997 ozone NAAQS and prior SO2 and lead NAAQS, refer to
the proposal for this final rule. (80 FR 15340)

B. Final Rule

    The EPA is finalizing the revocation of the 1997 primary annual
PM2.5 NAAQS for all purposes in attainment areas for that
NAAQS as described in Option 1. See 40 CFR 50.13(d). The EPA had
proposed that the revocation would be effective 1 year after the
effective date of designations for the 2012 primary annual
PM2.5 NAAQS. Those designations were effective on April 15,
2015. (80 FR 2206) Therefore, the proposed effective date of the
revocation was effectively April 15, 2016. However, this final rule
will not be effective before April 15, 2016. Therefore, the EPA is
establishing the effective date of this final rule as the effective
date of the revocation of the 1997 primary annual PM2.5
NAAQS.
    On the effective date of this final rule, the 1997 primary annual
PM2.5 NAAQS will be revoked for all purposes in all
attainment areas for that NAAQS, including the areas that were
initially designated attainment for the 1997 annual PM2.5
NAAQS. The final rule will have no practical impact on these areas that
have always attained the 1997 primary annual PM2.5 NAAQS.
These areas have never been required to conduct air quality planning
for this NAAQS for any CAA nonattainment purpose, although these areas
would continue to implement applicable PSD requirements.
    This final rule also revokes the 1997 primary annual
PM2.5 NAAQS in areas that have been redesignated to
attainment for this NAAQS (i.e., maintenance areas for this NAAQS).
These areas will be required to implement their approved maintenance
plan for the 1997 primary annual PM2.5 NAAQS and their PSD
program. The approved maintenance plan can only be revised if the
revision meets the requirements of CAA section 110(l) and, if
applicable, CAA section 193,
    Similarly, all states will be required to continue to implement
applicable control requirements in a FIP or approved SIP designed to
address the interstate transport requirements of CAA section
110(a)(2)(D)(i) and (ii) with respect to the 1997 primary annual
PM2.5 NAAQS, such as CAIR or CSAPR. These requirements
continue to be necessary for downwind nonattainment areas to make
progress towards attainment and to assure that the air quality
protection achieved in all areas is maintained into the future. These
provisions may only be modified if the revision meets the requirements
of section 110(l). A similar provision was finalized to preserve
interstate transport requirements with respect to the revocation of the
1997 ozone NAAQS. See 40 CFR 51.1105.
    For areas that remain nonattainment for the 1997 annual
PM2.5 NAAQS, the EPA will continue to redesignate areas to
attainment as appropriate. For an area that is redesignated to
attainment after the effective date of this final rule, the 1997
primary annual PM2.5 NAAQS will be revoked in such an area
on the effective date of its redesignation to attainment for that
NAAQS. The EPA will not revoke the 1997 primary annual PM2.5
NAAQS in any area as long as it is designated nonattainment for that
NAAQS. Until the 1997 primary annual PM2.5 NAAQS is revoked,
that NAAQS remains in effect, in parallel with the 2012 primary annual
PM2.5 NAAQS, and continues to apply independently and by its
own terms.
    After revocation of the 1997 primary annual PM2.5 NAAQS
in a given area, the designation for that standard is no longer in
effect. The only PM2.5 designations that remain in effect in

areas where the 1997 primary annual PM2.5 NAAQS has been
revoked are those for the 1997 24-hour PM2.5 NAAQS, the 1997
secondary annual PM2.5 NAAQS, the 2006 24-hour
PM2.5 NAAQS and the 2012 primary annual PM2.5
NAAQS. However, the EPA is retaining the listing of the designated
areas for the 1997 annual PM2.5 NAAQS in 40 CFR part 81, for
the purposes of identifying which areas remain designated as
nonattainment for the 1997 annual PM2.5 NAAQS and therefore
subject to the requirements of subpart 4 and the areas that have been
redesignated to attainment for the 1997 secondary annual
PM2.5 NAAQS. Accordingly, such references to historical
designations of areas where the 1997 primary annual PM2.5
NAAQS has been revoked should not be viewed as current designations
under CAA section 107(d) for the 1997 primary annual PM2.5.
As additional areas are redesignated to attainment for the 1997 annual
PM2.5 NAAQS, the EPA will indicate in the redesignation
rulemaking that the 1997 primary annual NAAQS is revoked on the
effective date of the redesignation.
    The EPA notes that areas designated nonattainment for the 1997
annual PM2.5 NAAQS at the time of the final rule's
revocation would be required to continue to comply with applicable
conformity requirements for that NAAQS. This obligation would continue
until the effective date of the redesignation of such an area to
attainment for the 1997 annual PM2.5 NAAQS. Transportation
and general conformity would apply in all areas that are designated
nonattainment for the more health protective 2012 primary annual
PM2.5 NAAQS on April 15, 2016, the end of the conformity
grace period (CAA section 176 (c)(c)(6) and 40 CFR 93.102(d)). Any
areas that are also designated nonattainment or redesignated to
attainment for the 1997 24-hour PM2.5 NAAQS or the 2006 24-
hour PM2.5 NAAQS are required to continue to make conformity
determinations for those NAAQS. See Section IX.B of this preamble for
more information about conformity implementation including information
pertaining to conformity requirements for the 1997 secondary annual
NAAQS.
    As with other NAAQS revocations, this revocation is framed in the
context of the CAA requirements that apply to the NAAQS transitions to
ensure that states and nonattainment areas continue to make progress
and do not reverse progress, or backslide, from improvements already
made in air quality. The CAA contains several provisions indicating
Congressional intent not to allow a state to alter or remove provisions
from an approved attainment or maintenance plan if the revision would
reduce air quality protection. CAA section 193 prohibits modification
of a control requirement in effect or required to be adopted as of
November 15, 1990 (the date of enactment of the 1990 CAA Amendments),
unless such a modification would ensure equivalent or greater emissions
reductions. CAA section 172(e), which addresses relaxations of the
NAAQS, requires protections for areas that have not attained the NAAQS
prior to a relaxation by requiring controls which are at least as
stringent as the controls applicable in nonattainment areas prior to
any such relaxation. CAA Section 110(l) provides that a SIP revision
cannot be approved if it will interfere with attainment or other CAA
requirements. Under CAA section 175A(d), an area that is redesignated
to attainment may, with an appropriate showing of no interference,
cease to implement a measure that is contained in the SIP at the time
of redesignation, but only if that measure is retained as a contingency
measure in the area's maintenance plan.279 280
---------------------------------------------------------------------------

    \279\ Nonattainment areas that were redesignated to attainment
with an approved CAA section 175A maintenance plan are referred to
throughout this document as ``maintenance areas.''
    \280\ Unimplemented requirements in the SIP or those shown to be
unnecessary for maintenance can be shifted to the contingency
measures portion of the SIP upon redesignation. See ``Procedures for
Processing Requests to Redesignate Areas to Attainment,'' Memorandum
from John Calcagni, Director, Air Quality Management Division,
September 4, 1992; ``State Implementation Plan (SIP) Requirements
for Areas Submitting Requests for Redesignation to Attainment of the
Ozone and Carbon Monoxide (CO) National Ambient Air Quality
Standards (NAAQS) On or After November 15, 1992,'' Memorandum from
Michael H. Shapiro, Acting Assistant Administrator for Air and
Radiation, September 17, 1993. As discussed elsewhere in this
document, an exception is made for NNSR, which can be removed from
the SIP completely and need not be retained as a contingency measure
after redesignation to attainment.
---------------------------------------------------------------------------

    The EPA has concluded that revoking the 1997 primary annual
PM2.5 NAAQS in attainment areas for that NAAQS is consistent
with the CAA and precedent in transitioning from a previous NAAQS to a
new, more stringent NAAQS. The approach taken in this final rule is
consistent with the approach taken in the transition from the past
SO2 and lead NAAQS to the current NAAQS for those
pollutants. Revoking the 1997 primary annual PM2.5 NAAQS
only in attainment areas ensures that any areas that remain designated
nonattainment for the 1997 annual PM2.5 NAAQS make progress
toward attaining that NAAQS as expeditiously as practicable by
implementing the CAA requirements that apply to PM2.5
nonattainment areas as described elsewhere in this final rule.
    Continued attainment of the 1997 primary annual PM2.5
NAAQS in areas that have been redesignated to attainment for that NAAQS
will be ensured through the ongoing implementation of the approved
maintenance plan that applies in these areas. These areas are required
to implement their approved CAA section 175A maintenance plan for the
1997 primary annual PM2.5 NAAQS. They are also required to
implement a PSD program for the annual PM2.5 NAAQS, unless
they are designated nonattainment for the 2012 primary annual
PM2.5 NAAQS where an NNSR program would apply.\281\
Revisions to the approved maintenance plan can only be made if the
revisions meet the requirements of CAA section 110(l) and, if
applicable, CAA section 193.
---------------------------------------------------------------------------

    \281\ Areas initially designated as attainment for the 1997
annual PM2.5 NAAQS would also be required to continue to
implement a PSD program unless an area was designated nonattainment
for the 2012 primary annual PM2.5 NAAQS or the 2006 24-
hour PM2.5 NAAQS. In that case, such an area would be
required to implement an NNSR program for that NAAQS.
---------------------------------------------------------------------------

    Under the selected option for revocation, it is unnecessary to
finalize anti-backsliding requirements that would apply to
nonattainment areas for the 1997 primary annual PM2.5 NAAQS,
because the NAAQS is only being revoked in attainment areas. For former
nonattainment areas that have been redesignated to attainment, the EPA
has already determined through the redesignation process and approval
of maintenance plans that all applicable requirements for the 1997
primary annual PM2.5 NAAQS--including anti-backsliding
requirements--have been fulfilled. For areas that were initially
designated as attainment for both the 1997 annual PM2.5
NAAQS and the 2012 primary annual PM2.5 NAAQS, the approved
PSD SIPs satisfy the obligation to submit an approvable maintenance
plan for the 2012 primary annual PM2.5 NAAQS under CAA
section 110(a)(1).
    The NAAQS is not being revoked in nonattainment areas. Therefore,
nonattainment areas will continue to comply with the requirements
applicable to their classification for the 1997 annual PM2.5
NAAQS as described in this final rule. For example, areas classified as
Serious will be required to implement BACT and BACM level controls and
implement an NNSR program that meets the Serious area requirements. Any
areas that do not attain by the Serious area deadline

would be required to comply with other requirements including most
stringent measures and a 5 percent plan. This would ensure that these
areas continue to make progress toward attaining the 1997 annual
PM2.5 NAAQS and attain that NAAQS as expeditiously as
practicable. It would also serve to provide early emissions reductions
toward attaining the 2012 primary annual PM2.5 NAAQS. When
these areas are eligible for redesignation to attainment, they may
submit a redesignation request including a maintenance plan for the
1997 primary annual PM2.5 NAAQS as required by CAA sections
107(d)(3) and 175A. On the effective date of the approval of the
redesignation request and maintenance plan, the 1997 primary annual
PM2.5 NAAQS would be revoked and the approved maintenance
plan along with the implementation of a PSD program for this NAAQS, if
they are designated attainment for the 2012 primary annual
PM2.5 NAAQS, would ensure continued attainment of the 1997
primary annual PM2.5 NAAQS.\282\ Revisions to the approved
maintenance plan can only be made if the revisions meet the
requirements of CAA section 110(l) and, if applicable, CAA section 193.
---------------------------------------------------------------------------

    \282\ Areas designated nonattainment for the 2012 primary annual
PM2.5 NAAQS would implement a NNSR program for that
NAAQS, instead of a PSD program for the 1997 primary annual PM.
---------------------------------------------------------------------------

    As the EPA proposed, the areas where the NAAQS is being revoked are
not required to submit a second 10-year maintenance plan for the 1997
primary annual PM2.5 NAAQS because there is no justification
for additional maintenance plan burdens to be imposed on these areas
solely because at one time they were designated nonattainment under the
revoked 1997 primary annual PM2.5 NAAQS. Not requiring a
second 10-year maintenance plan for these areas helps to minimize the
burden associated with preparing SIPs for a succession of the NAAQS of
increasing stringency. These areas are required to continue to
implement their approved maintenance plans for the 1997 primary annual
PM2.5 NAAQS. The maintenance plan remains in effect beyond
the end of the maintenance period. It may only be revised if the
revision complies with the requirements of CAA section 110(l) and, if
applicable, CAA section 193. Any areas that are designated
nonattainment for the 2012 primary annual PM2.5 NAAQS are
required to comply with the applicable CAA requirements as described in
this final rule.
    The EPA notes that most of the 39 areas that were initially
designated as nonattainment for the 1997 annual PM2.5 NAAQS
have already been redesignated to attainment (i.e., they are
maintenance areas) and their approved maintenance plans and PSD
programs along with the CAA's anti-backsliding provisions in CAA
sections 110(l) and 193 ensure continued attainment of the 1997 primary
annual PM2.5 NAAQS. If additional areas are redesignated to
attainment for the 1997 primary annual PM2.5 NAAQS, their
approved maintenance plan and PSD program for the 1997 primary annual
PM2.5 NAAQS would prevent backsliding for that NAAQS. As
stated previously, applicable conformity requirements would continue to
apply for the 1997 annual PM2.5 NAAQS until the effective
date of the redesignation of such an area to attainment for the 1997
annual PM2.5 NAAQS.
    In addition, transportation and general conformity will apply in
all areas that are designated nonattainment for the more health
protective 2012 primary annual PM2.5 NAAQS on April 15,
2016, the end of the conformity grace period (CAA section 176(c)(6) and
40 CFR 93.102(d)). In the D.C. Circuit Court's December 2006 decision
in South Coast v. EPA, as modified following rehearing, the Court held
with respect to the anti-backsliding approach for transportation
conformity that 1-hour ozone motor vehicle emissions budgets must be
used in transportation conformity determinations for the more
protective 1997 ozone NAAQS where such SIP motor vehicle emissions
budgets have been found adequate or approved, until SIP motor vehicle
emissions budgets for the 1997 8-hour ozone NAAQS are available.\283\
In addition, the Court affirmed more broadly that in order for
transportation conformity determinations to fulfill the requirements of
CAA section 176(c)(1), motor vehicle emissions budgets for a prior
NAAQS must be used in transportation conformity determinations under a
revised NAAQS until emissions budgets for the revised NAAQS are either
found adequate or are approved, but that conformity determinations need
not be made for a revoked standard. Therefore, areas designated
nonattainment for the 2012 primary annual PM2.5 NAAQS that
have adequate or approved SIP budgets for the 1997 annual
PM2.5 NAAQS must continue to use such budgets in
transportation conformity determinations until budgets for the 2012
primary annual PM2.5 NAAQS are found adequate or are
approved.\284\
---------------------------------------------------------------------------

    \283\ See South Coast Air Quality Management District v. EPA,
472 F.3d at 882.
    \284\ Such areas without adequate or approved SIP budgets for
either the 1997 annual PM2.5 NAAQS or the 2006 24-hour
PM2.5 NAAQS are required to demonstrate transportation
conformity using one of the interim emissions tests depending on
their classification as required by 40 CFR 93.119.
---------------------------------------------------------------------------

    With regard to general conformity, the D.C. Circuit Court did not
address the need for specific anti-backsliding measures in its initial
decision or in the modified decision on the South Coast litigation.
However, general conformity determinations will be required in
nonattainment areas for the 2012 primary annual NAAQS as required by
CAA section 176(c)(5) to ensure that the actions of federal agencies do
not cause a violation of that NAAQS, make an existing violation worse
or delay timely attainment of the NAAQS or an interim milestone.
    The EPA believes that revoking the 1997 primary annual
PM2.5 NAAQS is logical because it results in only one
primary annual PM2.5 NAAQS--the 2012 primary annual
PM2.5 NAAQS--applying for purposes of transportation and
general conformity in most areas, on the effective date of this
rulemaking, which is after the end of the 1-year conformity grace
period that applies to newly designated nonattainment areas. (CAA
section 176(c)(6)).
    An area that is attaining the more health-protective 2012 primary
annual PM2.5 NAAQS would no longer have to expend resources
to make conformity determinations or complete other applicable CAA air
quality planning requirements for any of the current annual
PM2.5 NAAQS after the 1997 primary annual PM2.5
NAAQS is revoked in the area. It should be noted that any areas that
are attaining the more health protective 2012 primary annual NAAQS are
also necessarily attaining the less stringent 1997 annual
PM2.5 NAAQS by a wide margin. See further information for
how conformity will be implemented for the 2012 PM2.5 NAAQS
in Section IX.B of this preamble.

C. Comments and Responses

1. Comments on Revocation Options 1 and 2 and Not Revoking the 1997
Primary Annual PM2.5 NAAQS
    Comment: Two commenters supported Option 1 and stated that any
areas that are attaining the more protective 2012 PM2.5
NAAQS are also necessarily attaining the less stringent 1997
PM2.5 NAAQS. Some commenters agreed that it is confusing to
continue to maintain two NAAQS for the same pollutant. Two commenters
stated that

revocation of the 1997 NAAQS would relieve the states of the
administrative burden of developing and submitting an additional
maintenance plan, as well as demonstrating transportation conformity,
for areas that are in compliance with the more stringent 2012
PM2.5 NAAQS.
    Response: The EPA is finalizing Option 1, and we agree with the
commenter that:

     Any area that is attaining the more health protective
2012 primary annual PM2.5 NAAQS of 12.0 [mu]g/m\3\ is
also attaining the 1997 annual PM2.5 NAAQS of 15.0 [mu]g/
m\3\;
     revoking the 1997 primary annual NAAQS in areas that
have either always been in attainment for that NAAQS or have been
redesignated to attainment reduces confusion concerning
implementation of the various PM2.5 NAAQS; and
     burden on states is reduced because a second 10-year
maintenance plan is not being required for the 1997 primary annual
PM2.5 NAAQS.

    If the 1997 primary annual PM2.5 NAAQS were to remain in
place after CAA requirements begin to apply for the 2012 primary annual
PM2.5 NAAQS, federal agencies, metropolitan planning
organizations (MPOs) and other state, local, and federal transportation
and air quality agencies in areas that are currently designated
nonattainment or maintenance for the 1997 annual PM2.5 NAAQS
and are now designated nonattainment for the 2012 primary annual NAAQS
would be required to implement CAA requirements for both annual
PM2.5 NAAQS concurrently. Additionally, some areas would
also be implementing requirements for the 2006 24-hour PM2.5
NAAQS, and two areas remain subject to requirements for the 1997 24-
hour PM2.5 NAAQS. This could lead to unnecessary complexity
for transportation conformity determinations, especially if an area's
boundaries for the various PM2.5 NAAQS differ from one
another, as boundaries for several areas do, and the same test of
conformity cannot be used for all the PM2.5 NAAQS. Even
where an area's boundaries are unchanged, different analysis years
under the transportation conformity rule may be required for each
PM2.5 NAAQS. It could also lead to general conformity
determinations being made in areas that are attainment for the 2012
primary annual PM2.5 NAAQS. Finally, state and local air
quality agencies would be required to continue attainment planning
activities for the 1997 primary annual PM2.5 NAAQS even if
they had air quality data that resulted in their being designated
attainment for the 2012 primary annual PM2.5 NAAQS.
    Comment: Some commenters opposed revocation of the 1997 primary
annual PM2.5 NAAQS but stated that if the EPA decides to
revoke the standard, then Option 1 is preferable since it more fully
complies with the health protection functions of the Act. This
commenter stated that Option 2 would violate the Act by creating
flexibility for regions that have failed to meet the standard. The
commenter provides a number of reasons for why Option 2 should not be
finalized. The commenter is primarily concerned that revoking the 1997
primary annual NAAQS in areas that are designated nonattainment for
that NAAQS at the time of revocation would delay improvements in air
quality and allow areas to postpone implementation of controls that
apply in PM2.5 areas that are classified as Serious. The
commenter also stated that the EPA must identify specific problems to
be addressed by revocation and a beneficial purpose for the revocation,
and not solely on a claim of the need for flexibility. While the D.C.
Circuit held that the EPA can revoke a NAAQS, the EPA cannot do so to
maximize its own discretion.
    Response: The EPA concluded that it is important to have all of the
CAA's tools in subpart 4 and, as applicable, subpart 1 available in
order to bring areas that are still violating the 1997 annual
PM2.5 NAAQS into attainment as expeditiously as practicable.
Finalizing Option 1, which revokes the 1997 primary annual
PM2.5 NAAQS in attainment areas, including areas
redesignated to attainment with an approved CAA section 175A
maintenance plan, leaves the CAA's compliance plan for PM areas in
place as Congress envisioned it. As described earlier, the EPA is
finalizing Option 1 for revoking the 1997 primary annual
PM2.5 NAAQS. Under Option 1, the primary annual NAAQS is
being revoked in areas that have always been attainment for the 1997
annual PM2.5 NAAQS and in areas that have been redesignated
to attainment for that NAAQS. Any area that remains designated
nonattainment for the 1997 annual PM2.5 NAAQS on the date of
the revocation will have the 1997 primary annual PM2.5 NAAQS
revoked after the area attains the 1997 annual PM2.5 NAAQS
and is redesignated to attainment consistent with CAA section
107(d)(3)(E) (including the requirement to have an approved CAA section
175A maintenance plan for the primary NAAQS). This means that any area
that remains designated nonattainment on the date of the revocation
will remain subject to all subpart 4 requirements, including Serious
area requirements such as BACT and BACM and more stringent NNSR
requirements. If the area does not attain by the Serious area deadline
and is not eligible for a 1-year attainment date extension, the area
would become subject to the requirement to develop a 5 percent plan. If
the area has still not attained, it would be subject to the
requirements in CAA section 179(d) for areas that fail to attain.
    The EPA agrees with the commenter's assessment that attaining the
1997 annual PM2.5 NAAQS as expeditiously as practicable has
both health and welfare benefits. The final rule ensures that
attainment of the 1997 PM2.5 NAAQS is achieved in all areas.
Furthermore, the final rule also requires that progress is made toward
attainment of the 2012 primary annual PM2.5 NAAQS in
nonattainment areas for that NAAQS. In addition, the 1997 annual
secondary NAAQS was retained to protect against certain welfare
effects. The EPA agrees that if we had revoked the 1997 primary annual
PM2.5 NAAQS in areas that are still violating that NAAQS
those areas would have started over as Moderate areas for the 2012
NAAQS, rather than being required to move forward with more stringent
measures that would have applied to a Serious area for the 1997 annual
PM2.5 NAAQS. The revocation of the 1997 primary annual
PM2.5 NAAQS as proposed under Option 1 and being finalized
is fully consistent with principles of CAA section 172(e). The 1997
primary annual PM2.5 NAAQS is only revoked after an area has
attained that NAAQS and been redesignated to attainment with an
approved CAA section 175A maintenance plan for that NAAQS. The NAAQS is
not being revoked in any area that remains designated nonattainment for
the NAAQS and areas that continue to violate the NAAQS continue to be
required to implement all of the measures required by subpart 4 (e.g.,
BACT, BACM and Serious area NNSR) and would be subject to additional
subpart 4 requirements (e.g., most stringent measures and a 5 percent
plan) if the area cannot or does not attain by the Serious area
deadline.
    The EPA is finalizing the revocation of the 1997 primary annual
PM2.5 NAAQS only in former nonattainment areas that have
been redesignated to attainment. Areas that continue to violate the
1997 annual NAAQS must attain that NAAQS and be redesignated to
attainment with an approved CAA section 175A maintenance plan for the
1997 primary annual PM2.5 NAAQS. The nonattainment areas
where the

NAAQS is not being revoked will be required to comply with all subpart
4 requirements in order to bring them into attainment with the 1997
annual PM2.5 NAAQS as expeditiously as practicable. In sum,
the final rule requires CAA subpart 4 to be implemented in all
nonattainment areas for the 1997 primary annual PM2.5 NAAQS.
    The EPA also disagrees with the commenter's assertion that the
final rule changes CAA subpart 4's requirements. Revocation under
Option 1 requires that nonattainment areas attain the 1997 annual
PM2.5 NAAQS and be redesignated to attainment before that
NAAQS is revoked. Any area that remains nonattainment and continues to
violate the 1997 annual NAAQS must first attain that NAAQS by complying
with the requirements for subpart 4 and then be redesignated to
attainment with an approved maintenance plan for the 1997 primary
annual PM2.5 NAAQS as described earlier.
    The EPA has concluded that the final rule fully complies with CAA
requirements and is consistent with both past precedents for revoking
the original SO2 and lead NAAQS and the tenets of the South
Coast decision concerning revocation of the 1-hour ozone NAAQS. (South
Coast Air Quality Management Dist. v. EPA, 472 F.3d 882) Areas that
continue to violate the 1997 annual NAAQS at the time of the initial
revocation are required to attain that NAAQS as expeditiously as
practicable through implementation of requirements in subpart 4. This
will ensure that these areas continue to make progress toward and
eventually attain the 1997 annual NAAQS and make progress toward
expeditious attainment of the more health protective 2012 primary
annual PM2.5 NAAQS.
    With regard to the comment that the EPA needs a better rationale
for the revocation, the EPA is revoking the 1997 primary annual
PM2.5 NAAQS in areas that have always been attainment for
that NAAQS and in areas that were initially designated nonattainment
but have been redesignated to attainment for that NAAQS because this
action ensures that only one primary annual PM2.5 NAAQS--the
more protective 2012 primary annual PM2.5 NAAQS--applies in
areas that are designated as attainment for the 1997 annual
PM2.5 NAAQS. These areas have successfully attained the less
stringent 1997 annual PM2.5 NAAQS and have a maintenance
plan in place to ensure that they do not slip back into nonattainment
for that NAAQS. These areas can only revise their approved maintenance
plans if the revision complies with CAA section 110(l) and, if
applicable, CAA section 193. Any of these areas that are designated
nonattainment for the more health protective 2012 primary annual
PM2.5 NAAQS can now focus their efforts on expeditiously
attaining the more protective NAAQS as required under subpart 4. Any of
these areas that are designated attainment for the more health
protective 2012 primary annual PM2.5 NAAQS can focus their
resources on other pressing air quality issues.
    The EPA believes that appropriately integrating prior requirements
with new goals facilitates coherent, effective and timely planning and
controls, and minimizes the separate potentially duplicative submission
of requirements left over from previous standards. Expeditious
attainment of the 1997 annual PM2.5 NAAQS in nonattainment
areas provides both health and welfare benefits that should not be
delayed by allowing nonattainment areas to restart the PM2.5
planning process under the Moderate area classification in subpart 4
for areas that are designated nonattainment for the more health
protective 2012 primary annual PM2.5 NAAQS. For these
reasons and the reasons stated earlier in Section X.a of this preamble,
the EPA believes that the revocation of the 1997 primary annual
PM2.5 NAAQS in areas that have always been attainment for
that NAAQS and in areas that have been redesignated to attainment for
that NAAQS provides the appropriate way to move toward attaining the
more protective standard in a timely and effective manner. This
approach ensures that progress made under previous PM2.5
NAAQS continues in attainment areas and continues in nonattainment
areas.
    Comment: Other commenters stated that it causes unnecessary
complexity, confusion, and burden to have multiple national standards
for the same criteria pollutant. The commenter stated that any concerns
about states and nonattainment areas not continuing to make progress or
reversing progress can be mitigated through anti-backsliding
requirements. On the other hand, two commenters supported the option of
not revoking the standard at all. One of these commenters believed that
past experience has led to confusion and litigation and has diminished
the urgency to attain a new NAAQS.
    Response: As described earlier, the EPA is finalizing revocation
Option 1, which leaves the nonattainment designation in place until the
area is redesignated to attainment and for those areas to fulfill the
requirements of CAA subpart 4 that apply to them. Revoking the 1997
primary annual PM2.5 NAAQS in areas that were designated
nonattainment at the time of the revocation could delay attainment of
that NAAQS and slow progress on attaining the 2012 primary annual
PM2.5 NAAQS because such areas would not be subject to all
of the planning requirements in CAA subpart 4 after the date of the
revocation. The EPA believes that the final rule simplifies the
revocation because the approved maintenance plan and an area's PSD
program serve to prevent backsliding. Anti-backsliding measures are not
required for nonattainment areas because the NAAQS is not being revoked
in nonattainment areas.
    Comment: Several commenters supported Option 2 and stated that it
is consistent with implementation rules for the other NAAQS, the 2012
primary annual PM2.5 NAAQS is more stringent and more
protective of health than the 1997 primary annual PM2.5
standard, and revocation of the 1997 PM2.5 NAAQS would
reduce the burden on states. One of these commenters also stated that,
in 1997 PM2.5 NAAQS maintenance areas that have good
PM2.5 air quality, revoking the 1997 PM2.5 NAAQS
in its entirety will alleviate transportation conformity requirements
as well as requirements for the submission of additional maintenance
plans.
    Response: As discussed in the proposal, the revocations of the
prior lead and SO2 NAAQS were accomplished in a manner
consistent with Option 1. (80 FR 15340) The EPA notes that both Options
1 and 2 would reduce burden on the states. Under Option 1, areas that
are redesignated to attainment would not be required to submit a second
10-year maintenance plan. However, under Option 1, areas that are
designated nonattainment at the time of the revocation would remain
subject to the CAA subpart 4 requirements applicable to the area until
it attains the NAAQS and is redesignated to attainment through approval
of a redesignation request and a CAA section 175A maintenance plan for
the primary NAAQS. Under Option 2, areas that remain designated
nonattainment at the time of the revocation would be required to
implement their approved SIPs for the 1997 annual PM2.5
NAAQS but would not be susceptible to a reclassification from Moderate
to Serious, and thus would not be required to adopt additional subpart
4 requirements including requirements for Serious areas that would
apply if such an area were reclassified. Not requiring Serious area
measures in such an area would delay emissions reductions and
improvements in air quality.

    The EPA also notes it retained the 1997 secondary annual NAAQS when
the PM2.5 NAAQS was revised in December 2012, thus, full
revocation of the 1997 standard would not be appropriate.
    Comment: Two commenters opposed the possible approach of not
revoking the 1997 primary annual PM2.5 NAAQS at this time
because it would be inconsistent with past actions when a NAAQS has
been replaced by the more stringent NAAQS and because it presents an
unnecessary burden.
    Response: The EPA is finalizing the proposed revocation of the 1997
primary annual PM2.5 NAAQS for the reasons set forth
earlier.
2. Comments on Anti-Backsliding Requirements Under Option 1
    Comment: Some commenters expressed concern that the proposal that
an approved CAA section 175A maintenance plan would serve as the anti-
backsliding measures may not be consistent with the language of CAA
section 172(e).
    Response: The EPA disagrees with the commenter. CAA section 172(e)
applies in areas that have not attained the prior NAAQS. In this final
rule, the EPA is only revoking the 1997 primary annual PM2.5
NAAQS in areas that have attained that NAAQS and been redesignated to
attainment with an approved CAA section 175A maintenance plan. The EPA
has determined that implementing the approved maintenance plan along
with a PSD program will serve to prevent backsliding in the areas where
the NAAQS is being revoked. The approved maintenance plan can only be
revised if the revision meets the requirements of CAA section 110(l)
and, if applicable, CAA section 193. In order for the 1997 primary
annual PM2.5 NAAQS to be revoked in the future in an area
that remains designated nonattainment at the time of the initial
revocation, such an area would have to attain the NAAQS, submit a
redesignation request including a maintenance plan for the primary
NAAQS, and the EPA would have to approve that submission. The 1997
primary annual PM2.5 NAAQS would then be revoked in such an
area on the effective date of the approval of the redesignation and
maintenance plan. That approved maintenance plan would serve to prevent
backsliding.
    Comment: Some commenters questioned whether the EPA's conclusion is
correct that under Option 1 there is no need for anti-backsliding
measures, because the area would have already attained. Commenter
stated there may be no need for implementing additional measures, but
it seems the state should continue to keep in effect those measures
that have brought it to attainment (except NNSR which by statute is
replaced by PSD permitting).
    Response: The final rule addresses this comment. Former
nonattainment areas where the 1997 primary annual PM2.5
NAAQS is being revoked are required to implement the approved
maintenance plan for that NAAQS and to implement a PSD program. The
approved maintenance plan remains in effect beyond the end of the
maintenance period. The approved maintenance plan can only be revised
if the revision complies with CAA section 110(l) and, if applicable,
CAA section 193.

XI. Environmental Justice Considerations

    The EPA believes the human health or environmental risk addressed
by this action will not have disproportionately high and adverse human
health or environmental effects on minority, low-income, or indigenous
populations because it would not negatively affect the level of
protection provided to human health or the environment under the
PM2.5 NAAQS. When promulgated, these regulations will
clarify the state implementation plan requirements and the NNSR
permitting requirements to be met by states in order to attain the
PM2.5 NAAQS as expeditiously as practicable. These
requirements are designed to protect all segments of the general
population. The EPA included specific discussion in this preamble about
actions that could be considered for the protection of minority, low-
income or indigenous populations in Section IV.D.6 of this preamble on
Moderate area attainment plan control strategies; Section VI.D.7 on
Serious area attainment plan control strategies; and Section IX.G of
this preamble, measures to ensure appropriate protections for
overburdened populations. In addition, as part of the consultation
activities conducted in developing this rule, the EPA participated in
training and outreach activities with representatives from
environmental justice organizations in a March 2014 conference held in
Research Triangle Park, NC titled, ``Clean Air Act Rulemaking and
Permitting Training for EJ Communities.'' These proposed regulations
are designed to protect and enhance the health and safety of these and
other populations, and they will not adversely affect the health or
safety of minority, low-income or indigenous populations.

XII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review

    This action is a significant regulatory action that was submitted
to the Office of Management and Budget (OMB) for review because it
raises novel policy issues. Any changes made in response to OMB
recommendations have been documented in the docket.\285\
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    \285\ Note that a regulatory impact analysis evaluating the
costs and benefits associated with attaining the 2012
PM2.5 NAAQS was released at the time the NAAQS review was
finalized. See ``Regulatory Impact Analysis for the Final Revisions
to the National Ambient Air Quality Standards for Particulate
Matter.'' U.S. Environmental Protection Agency, Office of Air
Quality and Planning Standards, Health and Environmental Impacts
Division, February 28, 2013. EPA-452/R-12-005.
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B. Paperwork Reduction Act (PRA)

    The information collection activities in this rule have been
submitted to the Office of Management and Budget (OMB) under the PRA.
The Information Collection Request (ICR) document prepared by the EPA
has been assigned the EPA ICR number 2258.04, OMB Control No. 2060-
0611. You can find a copy of the ICR in the docket for this rule, and
it is briefly summarized here.
    The EPA is finalizing this PM2.5 NAAQS SIP Requirements
Rule to describe the CAA requirements that must be met by states with
nonattainment areas required to develop attainment plans for attaining
and maintaining the NAAQS. The intended effect of the SIP Requirements
Rule is to provide certainty to states regarding their planning
obligations such that states may begin SIP development. Only states
with nonattainment areas are required to submit SIPs under this rule.
    For purposes of analysis of the estimated paperwork burden, the EPA
assumed there were 14 existing nonattainment areas for the 1997and 2006
PM2.5 NAAQS, and 14 designated nonattainment areas.\286\ The
attainment plan requirements would appear as 40 CFR 51.1000 through
51.1015 which implement CAA subsections 172(c)(1) and (2), and
189(a)(1)(B) and (C), 189(b)(1)(A) and (B) and 189(c). Some states have
new nonattainment areas and some states should already have information
from emission sources, as facilities should have provided this
information to meet 1997 and 2006

PM2.5 NAAQS SIP requirements, operating permits and/or
emissions reporting requirements. Such information does not generally
reveal the details of production processes. But, to the extent it may,
confidential business information for the affected facilities is
protected. Specifically, submissions of emissions and control
efficiency information that is confidential, proprietary and trade
secret and is not emission data are protected from disclosure under the
requirements of subsections 503(e) and 114(c) of the CAA.
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    \286\ On December 18, 2014, the EPA issued final area
designations for the 2012 annual national air quality standard for
fine particulate matter (PM2.5). The EPA designated 14
areas in six states as ``nonattainment.'' The effective date was
April 15, 2015.
---------------------------------------------------------------------------

    The annual state burden for this information collection for the 14
designated 2012 PM2.5 nonattainment areas, averaged over the
first 3 years of this ICR, is estimated to be a total of 42,000 labor
hours per year at an annual a labor cost of $2.5 million (present
value) over the 3 year period, or approximately $420,000 per state for
the 6 state respondents. The average annual reporting burden is
approximately 2,625 hours per response, with approximately 3 responses
per state for 16 state responses. There are no capital or operating and
maintenance costs associated with the proposal requirements. Burden is
defined at 5 CFR 1320.3(b).
    The annual state burden for this information collection for the 14
existing nonattainment areas for the 1997 and 2006 PM2.5
NAAQS, averaged over the first 3 years of this ICR, is estimated to be
a total of 48,600 labor hours per year at an annual labor cost of $2.9
million (present value) over the 3 year period, or approximately
$417,000 per state for the 7 state respondents. The average annual
reporting burden is approximately 3,240 hours per response, with
approximately two responses per state for 15 state responses. There are
no capital or operating and maintenance costs associated with the
proposal requirements. Burden is defined at 5 CFR 1320.3(b).
    An agency may not conduct or sponsor, and a person is not required
to respond to, a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for the
EPA's regulations in 40 CFR are listed in 40 CFR part 9.

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic
impact on a substantial number of small entities under the RFA. In
making this determination, the impact of concern is any significant
adverse economic impact on small entities. An agency may certify that a
rule will not have a significant economic impact on a substantial
number of small entities if the rule relieves regulatory burden, has no
net burden or otherwise has a positive economic effect on the small
entities subject to the rule. This rule will not impose any
requirements directly on small entities. Entities potentially affected
directly by this final rule include state, local and tribal governments
and none of these governments are small governments. Other types of
small entities are not directly subject to the requirements of this
rule.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain any unfunded mandate as described in
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect
small governments. This action imposes no enforceable duty on any
state, local or tribal governments or the private sector. The CAA
imposes the obligation for states to submit attainment plans to
implement the PM2.5 NAAQS. In this rule, the EPA is
clarifying those requirements. Therefore, this action is not subject to
the requirements of sections 202, 203, and 205 of the UMRA.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have
substantial direct effects on the states, on the relationship between
the national government and the states, or on the distribution of power
and responsibilities among the various levels of government.

F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments

    This final rule does not have tribal implications. It would not
have a substantial direct effect on one or more Indian tribes.
Furthermore, these regulation revisions do not affect the relationship
or distribution of power and responsibilities between the federal
government and Indian tribes. The CAA and the TAR establish the
relationship of the federal government and tribes in characterizing air
quality and developing plans to attain the NAAQS, and these revisions
to the regulations do nothing to modify that relationship. Thus,
Executive Order 13175 does not apply to this action.

G. Executive Order 13045: Protection of Children From Environmental
Health and Safety Risks

    The EPA interprets Executive Order 13045 as applying only to those
regulatory actions that concern environmental health or safety risks
that the EPA has reason to believe may disproportionately affect
children, per the definition of ``covered regulatory action'' in
section 2-202 of the Executive Order. This action is not subject to
Executive Order 13045 because it implements a previously promulgated
health or safety-based federal standard established pursuant to the
CAA.

H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use

    This action is not a ``significant energy action'' as defined in
Executive Order 13211 (66 FR 28355 (May 22, 2001)), because it is not
likely to have a significant adverse effect on the supply,
distribution, or use of energy.

I. National Technology Transfer and Advancement Act

    This rulemaking does not involve technical standards.

J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations

    The EPA believes the human health or environmental risk addressed
by this action will not have disproportionately high and adverse human
health or environmental effects on minority, low-income, or indigenous
populations. The results of this evaluation are contained in Section XI
of this preamble. However, because of the benefits of improved air
quality on low SES populations, the EPA conducted outreach to
communities on the proposal to encourage comment including a March 2014
environmental justice conference in Research Triangle Park, NC,
conference calls and a meeting with the National Environmental Justice
Advisory Committee.

K. Congressional Review Act (CRA)

    This action is subject to the CRA, and the EPA will submit a rule
report to each House of the Congress and to the Comptroller General of
the United States. This action is not a ``major rule'' as defined by 5
U.S.C. 804(2).

L. Determination Under Section 307(d)

    Pursuant to sections 307(d)(1)(E) and 307(d)(1)(V) of the CAA, the
Administrator proposes to determine that this action is subject to the
provisions of section 307(d). Under section 307(d)(1)(V), the
provisions of section 307(d) apply to ``such other

actions as the Administrator may determine.''

M. Judicial Review

    Section 307(b)(1) of the CAA indicates which Federal Courts of
Appeal have venue for petitions of review of final agency actions by
the EPA under the CAA. This section provides, in part, that petitions
for review must be filed in the U.S. Court of Appeals for the District
of Columbia Circuit (i) when the agency action consists of ``nationally
applicable regulations promulgated, or final actions taken, by the
Administrator'' or (ii) when such action is locally or regionally
applicable, if ``such action is based on a determination of nationwide
scope or effect and if in taking such action the Administrator finds
and publishes that such action is based on such a determination.''
    This rule implementing the PM2.5 SIP Requirements is
``nationally applicable'' within the meaning of CAA section 307(b)(1).
First, the rulemaking addresses the NAAQS that applies to all states
and territories in the U.S. Second, the rulemaking addresses issues
relevant to specific existing SIP provisions in states across the U.S.
that are located in each of the ten EPA regions, numerous federal
circuits and multiple time zones. Third, the rulemaking addresses a
common core of knowledge and analysis involved in formulating the
decision and a common interpretation of the requirements of the CAA
being applied to SIPs in states across the country. Fourth, the
rulemaking, by addressing issues relevant to appropriate SIP provisions
in one state, may have precedential impacts upon the SIPs of other
states nationwide. Courts have found similar rulemaking actions to be
of nationwide scope and effect.\287\
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    \287\ See, e.g., State of Texas, et al. v. EPA, 2011 U.S. App.
LEXIS 5654 (5th Cir. 2011) (finding SIP call to 13 states to be of
nationwide scope and effect and thus transferring the case to the
U.S. Court of Appeals for the D.C. Circuit in accordance with CAA
section 307(b)(1)).
---------------------------------------------------------------------------

    Under section 307(b)(1) of the Act, petitions for judicial review
of this action must be filed in the United States Court of Appeals for
the District of Columbia Circuit by October 24, 2016. Any such judicial
review is limited to only those objections that are raised with
reasonable specificity in timely comments. Filing a petition for
reconsideration by the Administrator of this final rule does not affect
the finality of this rule for the purposes of judicial review nor does
it extend the time within which a petition for judicial review may be
filed and shall not postpone the effectiveness of such rule or action.
Under section 307(b)(2) of the Act, the requirements of this final
action may not be challenged later in civil or criminal proceedings
brought by us to enforce these requirements.

XIII. Statutory Authority

    The statutory authority for this action is provided by 42 U.S.C.
7403, 7407, 7410, and 7601.

List of Subjects

40 CFR Part 50

    Environmental protection, Air pollution control, Intergovernmental
relations, Particulate matter, Sulfur dioxide, Nitrogen oxides,
Volatile organic compounds, Ammonia.

40 CFR Part 51

    Environmental protection, Air pollution control, Intergovernmental
relations, Particulate matter, Sulfur dioxide, Nitrogen oxides,
Volatile organic compounds, Ammonia.

40 CFR Part 93

    Environmental protection, Air pollution control, Intergovernmental
relations, Particulate matter, Sulfur dioxide, Nitrogen oxides,
Volatile organic compounds, Ammonia.

    Dated: July 29, 2016.
Gina McCarthy,
Administrator.

    For the reasons stated in the preamble, Title 40, Chapter I of the
Code of Federal Regulations is amended as follows:

PART 50--NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY
STANDARDS

0
1. The authority citation for part 50 continues to read as follows:

    Authority: 42 U.S.C. 7401, et seq.

0
2. In Sec.  50.13, add paragraph (d) to read as follows:

Sec.  50.13  National primary and secondary ambient air quality
standards for PM2.5.

* * * * *
    (d) Until the effective date of the final Fine Particulate Matter
National Ambient Air Quality Standards: State Implementation Plan
Requirements rule to be codified at 40 CFR 51.1000 through 51.1016, the
1997 annual PM2.5 NAAQS set forth in this section will
continue in effect, notwithstanding the promulgation of the 2012
primary annual PM2.5 NAAQS under Sec.  50.18. The 1997
primary annual PM2.5 NAAQS set forth in this section will no
longer apply upon the effective date of the final Fine Particulate
Matter National Ambient Air Quality Standards: State Implementation
Plan Requirements rule; except that for areas designated nonattainment
for the 1997 annual PM2.5 NAAQS set forth in this section as
of the effective date of the final Fine Particulate Matter National
Ambient Air Quality Standards: State Implementation Plan Requirements
rule, the requirements applicable to the 1997 primary annual
PM2.5 NAAQS set forth in this section will apply until the
effective date of an area's redesignation to attainment for the 1997
annual PM2.5 NAAQS pursuant to the requirements of section
107 of the Clean Air Act. The 1997 secondary annual PM2.5
NAAQS and the 1997 24-hour PM2.5 NAAQS shall remain in
effect. The area designations and classifications with respect to the
1997 annual and 24-hour PM2.5 NAAQS remain codified in 40
CFR part 81 in order to provide information on where the 1997 primary
annual PM2.5 NAAQS has been revoked and to facilitate the
implementation of the 1997 secondary annual PM2.5 NAAQS and
the 1997 24-hour PM2.5 NAAQS.

PART 51--REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF
IMPLEMENTATION PLANS

0
3. The authority citation for part 51 continues to read as follows:

    Authority: 23 U.S.C. 101; 42 U.S.C. 7401-7671q.

0
4. In Appendix A to subpart A of part 51, revise table 1 to read as
follows:

Appendix A to Subpart A of Part 51--Tables

 Table 1 to Appendix A of Subpart A--Emission Thresholds \1\ by Pollutant for Treatment as Point Source Under 40
                                                    CFR 51.30
----------------------------------------------------------------------------------------------------------------
                                    Every-year                               Triennial
                                 -------------------------------------------------------------------------------
            Pollutant             Type A sources
                                        \2\               Type B sources                  NAA sources \3\
----------------------------------------------------------------------------------------------------------------
(1) SO2.........................          >=2500  >=100.........................  >=100.
                                  ..............                                  PM2.5 (serious) >=70.
(2) VOC.........................           >=250  >=100.........................  >=100.
                                  ..............                                  O3 (serious) >=50.
                                  ..............                                  O3 (severe) >=25.
                                  ..............                                  O3 (extreme) >=10.
                                  ..............                                  PM2.5 (serious) >=70.
(3) NOX.........................          >=2500  >=100.........................  >=100.
                                                                                PM2.5 (serious) >=70.
(4) CO..........................          >=2500  >=1000........................  O3 (all areas) >=100.
                                                                                CO (all areas) >=100.
(5) Lead........................  ..............  >=0.5 (actual)................  >=0.5 (actual).
(6) Primary PM10................           >=250  >=100.........................  >=100.
                                  ..............                                  PM10 (serious) >=70.
(7) Primary PM2.5...............           >=250  >=100.........................  >=100.
                                  ..............                                  PM2.5 (serious) >=70.
(8) NH3.........................           >=250  >=100.........................  >=100.
                                                                                PM2.5 (serious) >=70.
----------------------------------------------------------------------------------------------------------------
\1\ Thresholds for point source determination shown in tons per year of potential to emit as defined in 40 CFR
  part 70, with the exception of lead. Reported emissions should be in actual tons emitted for the required time
  period.
\2\ Type A sources are a subset of the Type B sources and are the larger emitting sources by pollutant.
\3\ NAA = Nonattainment Area. The point source reporting thresholds vary by attainment status for SO2, VOC, NOX,
  CO, PM10, PM2.5, and NH3.

* * * * *

Subpart I--Review of New Sources and Modifications

0
5. In Sec.  51.165:
0
a. Revise paragraphs (a)(1)(iv)(A)(1) and (a)(1)(x)(A);
0
b. Add paragraph (a)(1)(x)(F);
0
c. Revise paragraph (a)(1)(xxxvii)(C)(2);
0
d. Remove paragraphs (a)(1)(xxxvii)(C)(3), and (4);
0
e. Revise paragraphs (a)(2)(i) and (a)(2)(ii)(A); and
0
f. Add paragraph (a)(13).
    The revisions and additions read as follows:

Sec.  51.165   Permit requirements.

    (a) * * *
    (1) * * *
    (iv)(A) * * *
    (1) Any stationary source of air pollutants that emits, or has the
potential to emit, 100 tons per year or more of any regulated NSR
pollutant (as defined in paragraph (a)(1)(xxxvii) of this section),
except that lower emissions thresholds shall apply in areas subject to
subpart 2, subpart 3, or subpart 4 of part D, title I of the Act,
according to paragraphs (a)(1)(iv)(A)(1)(i) through (viii) of this
section.
    (i) 50 tons per year of Volatile organic compounds in any serious
ozone nonattainment area.
    (ii) 50 tons per year of Volatile organic compounds in an area
within an ozone transport region, except for any severe or extreme
ozone nonattainment area.
    (iii) 25 tons per year of Volatile organic compounds in any severe
ozone nonattainment area.
    (iv) 10 tons per year of Volatile organic compounds in any extreme
ozone nonattainment area.
    (v) 50 tons per year of Carbon monoxide in any serious
nonattainment area for carbon monoxide, where stationary sources
contribute significantly to Carbon monoxide levels in the area (as
determined under rules issued by the Administrator).
    (vi) 70 tons per year of PM10 in any serious
nonattainment area for PM10.
    (vii) 70 tons per year of PM2.5 in any serious
nonattainment area for PM2.5.
    (viii) 70 tons per year of any individual precursor for
PM2.5 (as defined in paragraph (a)(1)(xxxvii) of this
section), in any serious nonattainment area for PM2.5.
* * * * *
    (x)(A) Significant means, in reference to a net emissions increase
or the potential of a source to emit any of the following pollutants, a
rate of emissions that would equal or exceed any of the following
rates:

Pollutant Emission Rate

Carbon monoxide: 100 tons per year (tpy)
Nitrogen oxides: 40 tpy
Sulfur dioxide: 40 tpy
Ozone: 40 tpy of Volatile organic compounds or Nitrogen oxides
Lead: 0.6 tpy
PM10: 15 tpy
PM2.5: 10 tpy of direct PM2.5 emissions; 40 tpy
of Sulfur dioxide emissions, 40 tpy of Nitrogen oxide emissions, or 40
tpy of VOC emissions, to the extent that any such pollutant is defined
as a precursor for PM2.5 in paragraph (a)(1)(xxxvii) of this
section.
* * * * *
    (F) For the purposes of applying the requirements of paragraph
(a)(13) of this section to modifications at existing major stationary
sources of Ammonia located in a PM2.5 nonattainment area, if
the plan requires that the control requirements of this section apply
to major stationary sources and major modifications of Ammonia as a
regulated NSR pollutant (as a PM2.5 precursor), the plan
shall also define ``significant'' for Ammonia for that area, subject to
the approval of the Administrator.
* * * * *
    (xxxvii) * * *
    (C) * * *
    (2) Sulfur dioxide, Nitrogen oxides, Volatile organic compounds and
Ammonia are precursors to PM2.5 in any PM2.5
nonattainment area.
* * * * *
    (2) Applicability procedures. (i) Each plan shall adopt a
preconstruction review program to satisfy the requirements of sections
172(c)(5) and 173 of the Act for any area designated nonattainment for
any national ambient air quality standard under subpart C of

40 CFR part 81. Such a program shall apply to any new major stationary
source or major modification that is major for the pollutant for which
the area is designated nonattainment under section 107(d)(1)(A)(i) of
the Act, if the stationary source or modification would locate anywhere
in the designated nonattainment area. Different pollutants, including
individual precursors, are not summed to determine applicability of a
major stationary source or major modification.
    (ii) * * *
    (A) Except as otherwise provided in paragraphs (a)(2)(iii) and (iv)
of this section, and consistent with the definition of major
modification contained in paragraph (a)(1)(v)(A) of this section, a
project is a major modification for a regulated NSR pollutant (as
defined in paragraph (a)(1)(xxxvii) of this section) if it causes two
types of emissions increases--a significant emissions increase (as
defined in paragraph (a)(1)(xxvii) of this section), and a significant
net emissions increase (as defined in paragraphs (a)(1)(vi) and (x) of
this section). The project is not a major modification if it does not
cause a significant emissions increase. If the project causes a
significant emissions increase, then the project is a major
modification only if it also results in a significant net emissions
increase.
* * * * *
    (13) The plan shall require that the control requirements of this
section applicable to major stationary sources and major modifications
of PM2.5 shall also apply to major stationary sources and
major modifications of PM2.5 precursors in a
PM2.5 nonattainment area, except that a reviewing authority
may exempt new major stationary sources and major modifications of a
particular precursor from the requirements of this section for
PM2.5 if the NNSR precursor demonstration submitted to and
approved by the Administrator shows that such sources do not contribute
significantly to PM2.5 levels that exceed the standard in
the area. Any demonstration submitted for the Administrator's review
must meet the conditions for a NNSR precursor demonstration as set
forth in Sec.  51.1006(a)(3).
* * * * *

0
6. Revise subpart Z to read as follows:
Subpart Z--Provisions for Implementation of PM2.5 National
Ambient Air Quality Standards
Sec.
51.1000 Definitions.
51.1001 Applicability of part 51.
51.1002 Classifications and reclassifications.
51.1003 Attainment plan due dates and submission requirements.
51.1004 Attainment dates.
51.1005 Attainment date extensions.
51.1006 Optional PM2.5 precursor demonstrations.
51.1007 [Reserved]
51.1008 Emissions inventory requirements.
51.1009 Moderate area attainment plan control strategy requirements.
51.1010 Serious area attainment plan control strategy requirements.
51.1011 Attainment demonstration and modeling requirements.
51.1012 Reasonable further progress (RFP) requirements.
51.1013 Quantitative milestone requirements.
51.1014 Contingency measures requirements.
51.1015 Clean data requirements.
51.1016 Continued applicability of the FIP and SIP requirements
pertaining to interstate transport under CAA section 110(a)(2)(D)(i)
and (ii) after revocation of the 1997 primary annual
PM2.5 NAAQS.

Subpart Z--Provisions for Implementation of PM2.5
National Ambient Air Quality Standards

Sec.  51.1000  Definitions.

    The following definitions apply for purposes of this subpart. Any
term not defined herein shall have the meaning as defined in 40 CFR
51.100 or Clean Air Act section 302.
    Act means the Clean Air Act as codified at 42 U.S.C. 7401-7671q
(2003).
    Additional feasible measure is any control measure that otherwise
meets the definition of ``best available control measure'' (BACM) but
can only be implemented in whole or in part beginning 4 years after the
date of reclassification of an area as Serious and no later than the
statutory attainment date for the area.
    Additional reasonable measure is any control measure that otherwise
meets the definition of ``reasonably available control measure'' (RACM)
but can only be implemented in whole or in part during the period
beginning 4 years after the effective date of designation of a
nonattainment area and no later than the end of the sixth calendar year
following the effective date of designation of the area.
    Applicable annual standard is the annual PM2.5 NAAQS
established, revised, or retained as a result of a particular
PM2.5 NAAQS review.
    Applicable attainment date means the latest statutory date by which
an area is required to attain a particular PM2.5 NAAQS,
unless the EPA has approved an attainment plan for the area to attain
such NAAQS, in which case the applicable attainment date is the date
approved under such attainment plan. If the EPA grants an extension of
an approved attainment date, then the applicable attainment date for
the area shall be the extended date.
    Applicable 24-hour standard is the 24-hour PM2.5 NAAQS
established, revised, or retained as a result of a particular
PM2.5 NAAQS review.
    Attainment projected inventory for the nonattainment area means the
projected emissions of direct PM2.5 and all PM2.5
precursors on the projected attainment date for the area. This
projected inventory includes sources included in the base year
inventory for the nonattainment area revised to account for changes in
direct PM2.5 and all PM2.5 precursors through
implementation of the plan and any additional sources of such emissions
expected within the boundaries of the nonattainment area by the
projected attainment date for the area.
    Average-season-day emissions means the sum of all emissions during
the applicable season divided by the number of days in that season.
    Base year inventory for the nonattainment area means the actual
emissions of direct PM2.5 and all PM2.5
precursors from all sources within the boundaries of a nonattainment
area in one of the 3 years used for purposes of designations or another
technically appropriate year.
    Best available control measure (BACM) is any technologically and
economically feasible control measure that can be implemented in whole
or in part within 4 years after the date of reclassification of a
Moderate PM2.5 nonattainment area to Serious and that
generally can achieve greater permanent and enforceable emissions
reductions in direct PM2.5 emissions and/or emissions of
PM2.5 plan precursors from sources in the area than can be
achieved through the implementation of RACM on the same source(s). BACM
includes best available control technology (BACT).
    Date of designation means the effective date of a PM2.5
area designation as promulgated by the Administrator.
    Date of reclassification means the effective date of a
PM2.5 area reclassification from Moderate to Serious as
promulgated by the Administrator.
    Direct PM2.5 emissions means solid or liquid particles
emitted directly from an air emissions source or activity, or reaction
products of gases emitted directly from an air emissions source or
activity which form particulate matter as they reach ambient
temperatures. Direct PM2.5 emissions include filterable and
condensable PM2.5 emissions

composed of elemental carbon, directly emitted organic carbon, directly
emitted sulfate, directly emitted nitrate, and other organic or
inorganic particles that exist or form through reactions as emissions
reach ambient temperatures (including but not limited to crustal
material, metals, and sea salt).
    Implemented means adopted by the state, fully approved into the SIP
by the EPA, and requiring expeditious compliance by affected sources
with installation and/or operation of any equipment, control device,
process change, or other emission reduction activity.
    Major stationary source means any stationary source of air
pollutant(s) that emits, or has the potential to emit 100 tons per year
or more of direct PM2.5 or any PM2.5 precursor in
any Moderate nonattainment area for the PM2.5 NAAQS, or 70
tons per year or more of direct PM2.5 or any
PM2.5 precursor in any Serious nonattainment area for the
PM2.5 NAAQS.
    Mobile source means mobile sources as defined by 40 CFR 51.50.
    Most stringent measure (MSM) is any permanent and enforceable
control measure that achieves the most stringent emissions reductions
in direct PM2.5 emissions and/or emissions of
PM2.5 plan precursors from among those control measures
which are either included in the SIP for any other NAAQS, or have been
achieved in practice in any state, and that can feasibly be implemented
in the relevant PM2.5 NAAQS nonattainment area.
    Nonpoint source means nonpoint sources as defined by 40 CFR 51.50.
    PM2.5 design value (DV) for a PM2.5
nonattainment area is the highest of the 3-year average concentrations
calculated for the ambient air quality monitors in the area, in
accordance with 40 CFR part 50, appendix N.
    PM2.5 NAAQS are the fine particulate matter National
Ambient Air Quality Standards codified at 40 CFR part 50.
    PM2.5 plan precursors are those PM2.5
precursors required to be regulated in the applicable attainment plan
and/or NNSR program.
    PM2.5 precursors are Sulfur dioxide (SO2),
Oxides of nitrogen (NOX), Volatile organic compounds (VOC),
and Ammonia (NH3).
    Point source means point sources as defined by 40 CFR 51.50.
    Precursor demonstration means an optional set of analyses provided
by a state that are designed to show that emissions of a particular
PM2.5 precursor do not contribute significantly to
PM2.5 levels that exceed the relevant PM2.5
standard in a particular nonattainment area. The three types of
precursor demonstrations provided in this rule are the comprehensive
precursor demonstration, the major stationary source precursor
demonstration, and the NNSR precursor demonstration.
    Reasonable further progress (RFP) means such annual incremental
reductions in emissions of direct PM2.5 and PM2.5
plan precursors as are required for the purpose of ensuring attainment
of the applicable PM2.5 NAAQS in a nonattainment area by the
applicable attainment date.
    Reasonably available control measure (RACM) is any technologically
and economically feasible measure that can be implemented in whole or
in part within 4 years after the effective date of designation of a
PM2.5 nonattainment area and that achieves permanent and
enforceable reductions in direct PM2.5 emissions and/or
PM2.5 plan precursor emissions from sources in the area.
RACM includes reasonably available control technology (RACT).
    RFP projected emissions means the estimated emissions for direct
PM2.5 and PM2.5 plan precursors by source
category or subcategory for the years in which quantitative milestones
are due for a nonattainment area.
    Subpart 1 means subpart 1 of part D of title I of the Act.
    Subpart 4 means subpart 4 of part D of title I of the Act.

Sec.  51.1001   Applicability of part 51.

    The provisions in subparts A through X of this part apply to areas
for purposes of the PM2.5 NAAQS to the extent they are not
inconsistent with the provisions of this subpart.

Sec.  51.1002  Classifications and reclassifications.

    (a) Initial classification as Moderate PM2.5
nonattainment area. Any area designated nonattainment for a
PM2.5 NAAQS shall be classified at the time of such
designation, by operation of law, as a Moderate PM2.5
nonattainment area.
    (b) Reclassification as Serious PM2.5 nonattainment
area. A Moderate nonattainment area shall be reclassified to Serious
under the following circumstances:
    (1) The EPA shall reclassify as Serious through notice-and-comment
rulemaking any Moderate PM2.5 nonattainment area that the
EPA determines cannot practicably attain a particular PM2.5
NAAQS by the applicable Moderate area attainment date.
    (2) A Moderate PM2.5 nonattainment area shall be
reclassified by operation of law as a Serious nonattainment area if the
EPA finds through notice-and-comment rulemaking that the area failed to
attain a particular PM2.5 NAAQS by the applicable Moderate
area attainment date.

Sec.  51.1003  Attainment plan due dates and submission requirements.

    (a) Nonattainment areas initially classified as Moderate. (1) For
any area designated as nonattainment and initially classified as
Moderate for a PM2.5 NAAQS, the state(s) shall submit a
Moderate area attainment plan that meets all of the following
requirements:
    (i) Base year emissions inventory requirements set forth at Sec.
51.1008(a)(1);
    (ii) Attainment projected emissions inventory requirements set
forth at Sec.  51.1008(a)(2);
    (iii) Moderate area attainment plan control strategy requirements
set forth at Sec.  51.1009;
    (iv) Attainment demonstration and modeling requirements set forth
at Sec.  51.1011;
    (v) Reasonable Further Progress (RFP) requirements set forth at
Sec.  51.1012;
    (vi) Quantitative milestone requirements set forth at Sec.
51.1013;
    (vii) Contingency measure requirements set forth at Sec.  51.1014;
and,
    (viii) Nonattainment new source review plan requirements pursuant
to Sec.  51.165.
    (2) The state(s) shall submit its Moderate area attainment plan to
the EPA no later than 18 months from the effective date of designation
of the area.
    (b) Nonattainment areas reclassified to Serious. (1) For any
nonattainment area reclassified to Serious for a PM2.5 NAAQS
under Sec.  51.1002(b), in addition to meeting the Moderate area
attainment plan submission requirements set forth at Sec.  51.1003(a),
the state(s) shall submit a Serious area attainment plan that meets all
of the following requirements:
    (i) Base year emissions inventory requirements set forth at Sec.
51.1008(b)(1);
    (ii) Attainment projected emissions inventory requirements set
forth at Sec.  51.1008(b)(2);
    (iii) Serious area attainment plan control strategy requirements
set forth at Sec.  51.1010;
    (iv) Attainment demonstration and modeling requirements set forth
at Sec.  51.1011;
    (v) Reasonable Further Progress (RFP) requirements set forth at
Sec.  51.1012;
    (vi) Quantitative milestone requirements set forth at Sec.
51.1013;
    (vii) Contingency measure requirements set forth at Sec.  51.1014;
and,
    (viii) Nonattainment new source review plan requirements pursuant
to Sec.  51.165.
    (2) The state(s) shall submit its Serious area attainment plan to
the EPA according to the following schedule:

    (i) Discretionary reclassification. (A) For any nonattainment area
reclassified to Serious for a particular PM2.5 NAAQS under
Sec.  51.1002(b)(1) because the EPA determined it cannot practicably
attain the NAAQS by the applicable Moderate area attainment date, the
state(s) shall submit to the EPA no later than 18 months from the
effective date of reclassification the portion of the Serious area
attainment plan that meets the following requirements:
    (1) Base year emissions inventory requirements set forth at Sec.
51.1008(b)(1);
    (2) Serious area attainment plan control strategy requirements set
forth at Sec.  51.1010(a)(1) through (4); and,
    (3) Nonattainment new source review plan requirements pursuant to
Sec.  51.165.
    (B) The state(s) shall submit to the EPA the portion of the Serious
area attainment plan that meets the requirements set forth at
paragraphs (b)(1)(ii), and (b)(1)(iv) through (vii) of this section to
the EPA by a date that is no later than 4 years after the effective
date of reclassification, or 2 years prior to the attainment date,
whichever is earlier.
    (ii) Mandatory reclassification. For any nonattainment area
reclassified to Serious for a particular PM2.5 NAAQS under
Sec.  51.1002(b)(2) because the EPA determined it failed to attain the
NAAQS by the applicable Moderate area attainment date, the state(s)
shall submit to the EPA a Serious area attainment plan meeting the
requirements set forth at paragraphs (b)(1)(i) through (viii) of this
section within 18 months from the effective date of reclassification,
or 2 years before the attainment date, whichever is earlier.
    (iii) If the state(s) submits to the EPA a request for a Serious
area attainment date extension simultaneous with the Serious area
attainment plan due under paragraph (b)(1) of this section, such a plan
shall meet the most stringent measure (MSM) requirements set forth at
Sec.  51.1010(b) in addition to the BACM and BACT and additional
feasible measure requirements set forth at Sec.  51.1010(a).
    (c) Serious nonattainment areas subject to CAA section 189(d) for
failing to attain the PM2.5 NAAQS by the applicable Serious
area attainment date. (1) For any Serious nonattainment area that fails
to attain the PM2.5 NAAQS by the applicable Serious area
attainment date, the state(s) shall submit a revised Serious area
attainment plan that demonstrates that each year the area will achieve
at least a 5 percent reduction in emissions of direct PM2.5
or a 5 percent reduction in emissions of a PM2.5 plan
precursor based on the most recent emissions inventory for the area.
The revised attainment plan shall meet the following requirements:
    (i) Emissions inventory requirements set forth at Sec.
51.1008(c)(1);
    (ii) Emissions inventory requirements set forth at Sec.
51.1008(c)(2);
    (iii) Serious area attainment plan control strategy requirements
set forth at Sec.  51.1010;
    (iv) Attainment demonstration and modeling requirements set forth
at Sec.  51.1011;
    (v) Reasonable Further Progress (RFP) requirements set forth at
Sec.  51.1012;
    (vi) Quantitative milestone requirements set forth at Sec.
51.1013;
    (vii) Contingency measure requirements set forth at Sec.  51.1014;
and
    (viii) Nonattainment new source review plan requirements pursuant
to Sec.  51.165.
    (2) The state(s) shall submit to the EPA the revised attainment
plan meeting the requirements set forth at paragraphs (c)(1)(i) through
(vii) of this section no later than 12 months from the applicable
Serious area attainment date that was previously missed.
    (d) Any attainment plan submitted to the EPA under this section
shall establish motor vehicle emissions budgets for the projected
attainment year for the area, if applicable. The state shall develop
such budgets according to the requirements of the transportation
conformity rule as they apply to PM2.5 nonattainment areas
(40 CFR part 93).

Sec.  51.1004  Attainment dates.

    (a) The state shall submit a projected attainment date as part of
its attainment plan submission under Sec.  51.1003 for any
PM2.5 NAAQS nonattainment area located in whole or in part
within its boundaries. The state shall justify the projected attainment
date for each such nonattainment area (or portion of a nonattainment
area) as part of the demonstration of attainment developed and
submitted according to the requirements set forth at Sec.  51.1011 and
according to the following:
    (1) Nonattainment areas initially classified as Moderate.
    (i) Except for nonattainment areas that meet the criterion under
paragraph (a)(1)(ii) of this section, the projected attainment date for
a Moderate PM2.5 nonattainment area shall be as expeditious
as practicable through the implementation of all control measures
required under Sec.  51.1009. The attainment date may be as late as the
end of the sixth calendar year after the effective date of designation
if the state demonstrates that the implementation of the control
measures that qualify as RACM, RACT, and additional reasonable
measures, but that are not necessary for demonstrating attainment by
the end of the sixth calendar year after the effective date of
designation, will not collectively advance the attainment date by at
least 1 year.
    (ii) The projected attainment date for a Moderate PM2.5
nonattainment area which the state demonstrates cannot practicably
attain the applicable PM2.5 NAAQS by the end of the sixth
calendar year after the effective date of designation of the area with
the implementation of all control measures required under Sec.  51.1009
shall be the end of the sixth calendar year after the effective date of
designation unless and until the area is reclassified as Serious
according to Sec.  51.1002.
    (2) Nonattainment areas reclassified to Serious. (i) Except for
nonattainment areas that meet the criterion under paragraph (a)(2)(ii)
of this section, the projected attainment date for a Serious
PM2.5 nonattainment area shall be as expeditious as
practicable with the implementation of all control measures required
under Sec.  51.1010 but no later than the end of the tenth calendar
year after the effective date of designation.
    (ii) A state that submits an attainment plan that demonstrates that
a Serious PM2.5 nonattainment area cannot practicably attain
the PM2.5 NAAQS by the end of the tenth calendar year
following the effective date of designation of the area with the
implementation of all control measures required under Sec.  51.1010(a)
must request an extension of the Serious area attainment date
consistent with Sec.  51.1005(b). The request must propose a projected
attainment date for the nonattainment area that is as expeditious as
practicable, but no later than the end of the fifteenth calendar year
following the effective date of designation of the area.
    (3) Serious nonattainment areas subject to CAA section 189(d) for
failing to attain by the applicable Serious area attainment date. The
projected attainment date for a Serious PM2.5 nonattainment
area that failed to attain the PM2.5 NAAQS by the applicable
Serious area attainment date shall be as expeditious as practicable,
but no later than 5 years following the effective date of the EPA's
finding that the area failed to attain by the original Serious area
attainment date, except that the Administrator may extend the
attainment date to the extent the Administrator deems appropriate, for
a period no greater than 10 years from the effective date of the EPA's
determination that the area failed to attain, considering the severity
of nonattainment and the availability and feasibility of pollution
control measures.

    (b) Except for attainment plans that meet the conditions of
paragraphs (a)(1)(ii) or (a)(3) of this section, the Administrator
shall approve an attainment date at the same time and in the same
manner in which the Administrator approves the attainment plan for the
area.
    (1) In accordance with paragraph (a)(1)(ii) of this section, if a
state demonstrates that a Moderate PM2.5 nonattainment area
cannot practicably attain the PM2.5 NAAQS by the end of the
sixth calendar year following the effective date of designation of the
area, the EPA shall proceed under the provisions of Sec.  51.1002(b)(1)
to reclassify the area to Serious through notice-and-comment
rulemaking.
    (2) [Reserved]

Sec.  51.1005  Attainment date extensions.

    (a) Nonattainment areas initially classified as Moderate. (1) A
state with a Moderate PM2.5 nonattainment area may apply for
a 1-year attainment date extension for the area if the following
conditions are met in the calendar year that includes the applicable
attainment date for the area:
    (i) The state has complied with all requirements and commitments
pertaining to the area in the applicable implementation plan;
    (ii) For an area designated nonattainment for a particular 24-hour
PM2.5 NAAQS for which the state seeks an attainment date
extension, the 98th percentile 24-hour concentration at each monitor in
the area for the calendar year that includes the applicable attainment
date is less than or equal to the level of the applicable 24-hour
standard (calculated according to the data analysis requirements in 40
CFR part 50, appendix N);
    (iii) For an area designated nonattainment for a particular annual
PM2.5 NAAQS for which the state seeks an attainment date
extension, the annual average concentration at each monitor in the area
for the calendar year that includes the applicable attainment date is
less than or equal to the level of the applicable annual standard
(calculated according to the data analysis requirements in 40 CFR part
50, appendix N).
    (2) The applicable implementation plan for a Moderate
PM2.5 nonattainment area for which a state seeks an
attainment date extension is the plan submitted to the EPA to meet the
requirements of Sec.  51.1003(a).
    (3) A Moderate area 1-year attainment date extension runs from
January 1 to December 31 of the year following the year that includes
the applicable attainment date.
    (4) A state with a Moderate area that received an initial 1-year
attainment date extension may apply for a second 1-year attainment date
extension for the area if the state meets the conditions described in
paragraph (a)(1) of this section for the first 1-year extension year.
    (b) Nonattainment areas reclassified as Serious. (1) A state may
apply for one attainment date extension not to exceed 5 years for a
Serious nonattainment area if the following conditions are met:
    (i) The state demonstrates that attainment of the applicable
PM2.5 NAAQS by the approved attainment date for the area
would be impracticable or, in the absence of an approved attainment
date, attainment of the applicable PM2.5 NAAQS by the
applicable statutory attainment date for the area would be
impracticable;
    (ii) The state has complied with all requirements and commitments
pertaining to the area in the applicable implementation plan; and,
    (iii) The state demonstrates that the attainment plan for the area
includes the most stringent measures (MSM) that are included in the
attainment plan of any state or are achieved in practice in any state,
and can feasibly be implemented in the area consistent with Sec.
51.1010(b).
    (2) At the time of application for an attainment date extension,
the state shall submit to the EPA a Serious area attainment plan that
meets the following requirements:
    (i) Base year and attainment projected emissions inventory
requirements set forth at Sec.  51.1008(b);
    (ii) Most stringent measures (MSM) requirement described under
paragraph (b)(1)(iii) of this section and Sec.  51.1010(b), and best
available control measures not previously submitted;
    (iii) Attainment demonstration and modeling requirements set forth
at Sec.  51.1011 that justify the state's conclusion under paragraph
(b)(1)(i) of this section, and that demonstrate attainment as
expeditiously as practicable;
    (iv) Reasonable Further Progress (RFP) requirements set forth at
Sec.  51.1012;
    (v) Quantitative milestone requirements set forth at Sec.  51.1013;
    (vi) Contingency measure requirements set forth at Sec.  51.1014;
and,
    (vii) Nonattainment new source review plan requirements pursuant to
Sec.  51.165.
    (3) The applicable implementation plan for a Serious
PM2.5 nonattainment area for which a state seeks an
attainment date extension under Sec.  51.1004(a)(2)(ii) is the plan
submitted to the EPA to meet the requirements set forth at Sec.
51.1003(a).
    (4) The applicable implementation plan for a Serious
PM2.5 nonattainment area for which a state seeks an
attainment date extension under Sec.  51.1004(a)(2)(i) is the plan
submitted to the EPA to meet the requirements set forth at Sec.
51.1003(b)(1).
    (5) A state applying for an attainment date extension for a Serious
nonattainment area under Sec.  51.1004(a)(2)(ii) shall submit to the
EPA a request for an extension at the same time as it submits the
Serious area attainment plan due under Sec.  51.1003(b)(1).
    (6) A state applying for an attainment date extension for a Serious
nonattainment area subsequent to submitting an initial Serious area
attainment plan that demonstrated attainment of the NAAQS by the
applicable attainment date consistent with Sec.  51.1004(a)(2)(i) at
the time of submission may apply for such an extension no later than 60
calendar days prior to the approved attainment date for the area or, in
the absence of an approved attainment date, no later than 60 calendar
days prior to the applicable statutory attainment date for the area.
    (c) Serious nonattainment areas subject to CAA section 189(d) for
failing to attain by the applicable Serious area attainment date. If a
Serious area fails to attain a particular PM2.5 NAAQS by the
applicable Serious area attainment date, the area is then subject to
the requirements of section 189(d) of the Act, and, for this reason,
the state is prohibited from requesting an extension of the applicable
Serious area attainment date for such area.
    (d) For any attainment date extension request submitted pursuant to
this section, the requesting state (or states) shall submit a written
request and evidence of compliance with these regulations which
includes both of the following:
    (1) Evidence that all control measures submitted in the applicable
attainment plan have been implemented, and
    (2) Evidence that the area has made emission reduction progress
that represents reasonable further progress toward timely attainment of
the applicable PM2.5 NAAQS.
    (e) For a PM2.5 nonattainment area located in two or
more states or jurisdictions, all states and/or jurisdictions in which
such area is located shall submit separate attainment date extension
requests for the area consistent with the requirements set forth at
paragraph (d) of this section.

Sec.  51.1006  Optional PM2.5 precursor demonstrations

    (a) A state may elect to submit to the EPA one or more precursor
demonstrations for a specific nonattainment area. The analyses
conducted in support of any precursor demonstration must be based on
precursor emissions attributed to sources and activities in the
nonattainment area.
    (1) A comprehensive precursor demonstration must show that
emissions of a particular precursor from all existing stationary, area,
and mobile sources located in the nonattainment area do not contribute
significantly to PM2.5 levels that exceed the standard in
the area. If the state chooses to conduct a comprehensive precursor
demonstration, the state must conduct the analysis in paragraph
(a)(1)(i) of this section and it may conduct the analysis in paragraph
(a)(1)(ii) of this section.
    (i) Concentration-based contribution analysis. The comprehensive
precursor demonstration must evaluate the contribution of a particular
precursor to PM2.5 levels in the area. If the contribution
of the precursor to PM2.5 levels in the area is not
significant, based on the facts and circumstances of the area, then the
EPA may approve the demonstration.
    (ii) Sensitivity-based contribution analysis. If the concentration-
based contribution analysis does not support a finding of insignificant
contribution, based on the facts and circumstances of the area, then
the state may choose to submit an analysis evaluating the sensitivity
of PM2.5 levels in the area to a decrease in emissions of
the precursor in order to determine whether the resulting air quality
changes are significant. If the estimated air quality changes
determined in the sensitivity analysis are not significant, based on
the facts and circumstances of the area, then the EPA may approve the
demonstration.
    (iii) If a comprehensive precursor demonstration is approved by the
EPA, the state will not be required to control emissions of the
relevant precursor from existing sources in the current attainment
plan.
    (2) A major stationary source precursor demonstration must show
that emissions of a particular precursor from all existing major
stationary sources located in the nonattainment area do not contribute
significantly to PM2.5 levels that exceed the standard in
the area. If the state chooses to conduct a major stationary source
precursor demonstration, the state must conduct the analysis in
paragraph (a)(2)(i) of this section and it may conduct the analysis in
paragraph (a)(2)(ii) of this section.
    (i) Concentration-based contribution analysis. The major stationary
source precursor demonstration must evaluate the contribution of major
source emissions of a particular precursor to PM2.5 levels
in the area. If the contribution of the precursor to PM2.5
levels in the area is not significant, based on the facts and
circumstances of the area, then the EPA may approve the demonstration.
    (ii) Sensitivity-based contribution analysis. If the concentration-
based contribution analysis does not support a finding of insignificant
contribution, based on the facts and circumstances of the area, then
the state may choose to submit an analysis evaluating the sensitivity
of PM2.5 levels in the area to a decrease in emissions of
the precursor in order to determine whether the resulting air quality
changes are significant. If the estimated air quality changes
determined in the sensitivity analysis are not significant, based on
the facts and circumstances of the area, then the EPA may approve the
demonstration.
    (iii) If a major stationary source precursor demonstration is
approved by the EPA, the state will not be required to control
emissions of the relevant precursor from existing major stationary
sources in the current attainment plan.
    (3)(i) A NNSR precursor demonstration must evaluate the sensitivity
of PM2.5 levels in the nonattainment area to an increase in
emissions of a particular precursor in order to determine whether the
resulting air quality changes are significant. If the estimated air
quality changes determined in the sensitivity analysis are not
significant, based on the facts and circumstances of the area, the
state may use that information to identify new major stationary sources
and major modifications of a precursor that will not be considered to
contribute significantly to PM2.5 levels that exceed the
standard in the nonattainment area.
    (ii) If a NNSR precursor demonstration for a particular
PM2.5 nonattainment area is approved, the state may exempt
such new major stationary sources or major modifications of the
particular precursor from the requirements for PM2.5 in
Sec.  51.165.
    (b) If an area with one or more precursor demonstrations approved
by the EPA is required to submit another PM2.5 attainment
plan in accordance with Sec.  51.1003 of this part, the current
precursor demonstration(s) will not apply to the new plan. The state
must submit the appropriate updated precursor demonstration(s) if it
seeks to exempt sources of a particular precursor from control
requirements in the new Serious area attainment demonstration or in the
NNSR program for the Serious area.

Sec.  51.1007  [Reserved]

Sec.  51.1008  Emissions inventory requirements.

    (a) For any nonattainment area initially classified as Moderate,
the state shall submit to the EPA all of the following:
    (1) A base year inventory for the nonattainment area for all
emissions sources that meets the following minimum criteria:
    (i) The inventory year shall be one of the 3 years for which
monitored data were used for designations or another technically
appropriate inventory year if justified by the state in the plan
submission.
    (ii) The inventory shall include actual emissions of all sources
within the nonattainment area.
    (iii) The emissions values shall be either annual total emissions,
average-season-day emissions, or both, as appropriate for the relevant
PM2.5 NAAQS. The state shall include as part of the plan a
rationale for providing annual or seasonal emissions, and the
justification for the period used for any seasonal emissions
calculations.
    (iv) The inventory shall include direct PM2.5 emissions,
separately reported PM2.5 filterable and condensable
emissions, and emissions of the scientific PM2.5 precursors,
including precursors that are not PM2.5 plan precursors
pursuant to a precursor demonstration under Sec.  51.1006.
    (v) The state shall report emissions as point sources according to
the point source emissions thresholds of the Air Emissions Reporting
Requirements (AERR), 40 CFR part 51, subpart A.
    (vi) The detail of the emissions inventory shall be consistent with
the detail and data elements required by 40 CFR part 51, subpart A.
    (2) An attainment projected inventory for the nonattainment area
that meets the following minimum criteria:
    (i) The year of the projected inventory shall be the most
expeditious year for which projected emissions show modeled
PM2.5 concentrations below the level of the NAAQS.
    (ii) The emissions values shall be projected emissions of the same
sources included in the base year inventory for the nonattainment area
(i.e., those only within the nonattainment area) and any new sources.
The state shall include in this inventory projected emissions

growth and contraction from both controls and other causes during the
relevant period.
    (iii) The temporal period of emissions shall be the same temporal
period (annual, average-season-day, or both) as the base year inventory
for the nonattainment area.
    (iv) Consistent with the base year inventory for the nonattainment
area, the inventory shall include direct PM2.5 emissions,
separately reported PM2.5 filterable and condensable
emissions, and emissions of the scientific PM2.5 precursors,
including precursors that are not PM2.5 plan precursors
pursuant to a precursor demonstration under Sec.  51.1006 of this part.
    (v) The same sources reported as point sources in the base year
inventory for the nonattainment area shall be included as point sources
in the attainment projected inventory for the nonattainment area.
Stationary nonpoint and mobile source projected emissions shall be
provided using the same detail (e.g., state, county, and process codes)
as the base year inventory for the nonattainment area.
    (vi) The same detail of the emissions included shall be consistent
with the level of detail and data elements as in the base year
inventory for the nonattainment area (i.e., as required by 40 CFR part
41, subpart A).
    (b) For any nonattainment area reclassified as Serious, the state
shall submit to the EPA all of the following:
    (1) For purposes of meeting the emissions inventory requirements of
CAA section 172(c)(3), a base year inventory for the nonattainment area
for all emissions sources that meets the requirements listed under
paragraphs (a)(1) (ii) through (a)(1)(vi) of this section. In addition,
the inventory shall use the Serious area definition of a major source
listed under Sec.  51.165(a)(1)(iv)(A), and(a)(1)(vii) and (viii), and
consistent with Table 1 of Appendix A to subpart A of this part in
determining sources to include as point sources. Finally, the inventory
year shall be one of the 3 years for which monitored data were used for
reclassification to Serious, or another technically appropriate
inventory year if justified by the state in the plan submission.
    (2) An attainment projected inventory for the nonattainment area
that meets the criteria listed under paragraph (a)(2) of this section.
    (c) Serious nonattainment areas subject to CAA section 189(d) for
failing to attain a PM2.5 NAAQS by the applicable Serious
area attainment date. No later than 12 months after the EPA finds
through notice-and-comment rulemaking that a Serious nonattainment
area, or portion thereof contained within a state's borders, fails to
attain a PM2.5 NAAQS by the applicable attainment date and
thus becomes subject to the requirements under CAA section 189(d), the
state shall submit to the EPA all of the following:
    (1) For purposes of meeting the emissions inventory requirements of
CAA section 172(c)(3), a base year inventory for the nonattainment area
for all emissions sources that meets the requirements listed under
paragraphs (a)(1) (ii) through (a)(1)(vi) of this section. In addition,
the inventory shall use the Serious area definition of a major source
listed under Sec.  51.165(a)(1)(iv)(A)(vii) and (viii) and consistent
with Table 1 of Appendix A to subpart A of this part in determining
sources to include as point sources. The inventory year shall be one of
the 3 years for which monitored data were used to determine that the
area failed to attain the PM2.5 NAAQS by the applicable
Serious area attainment date, or another technically appropriate
inventory year if justified by the state in the plan submission.
    (2) An attainment projected inventory for the nonattainment area as
defined by Sec.  51.1000(e) and that meets the criteria listed under
paragraph (a)(2) of this section.

Sec.  51.1009  Moderate area attainment plan control strategy
requirements.

    (a) The state shall identify, adopt, and implement control
measures, including control technologies, on sources of direct
PM2.5 emissions and sources of emissions of PM2.5
plan precursors located in any Moderate PM2.5 nonattainment
area or portion thereof located within the state consistent with the
following:
    (1) The state shall identify all sources of direct PM2.5
emissions and all sources of emissions of PM2.5 precursors
in the nonattainment area in accordance with the emissions inventory
requirements of Sec.  51.1008(a).
    (2) The state shall identify all potential control measures to
reduce emissions from all sources of direct PM2.5 emissions
and all sources of emissions of PM2.5 plan precursors in the
nonattainment area identified under paragraph (a)(1) of this section.
    (i) The state is not required to identify and evaluate potential
control measures to reduce emissions of a particular PM2.5
precursor from any existing sources if the state has submitted a
comprehensive precursor demonstration approved by the EPA pursuant to
Sec.  51.1006, except where the EPA requires such information as
necessary to evaluate the comprehensive precursor demonstration
pursuant to Sec.  51.1006(a)(1)(ii).
    (ii) The state is not required to identify and evaluate potential
control measures to reduce emissions of a particular PM2.5
precursor from any existing major stationary sources if the state has
submitted a major stationary source precursor demonstration approved by
the EPA pursuant to Sec.  51.1006, except where the EPA requires such
information as necessary to evaluate the major stationary source
precursor demonstration pursuant to Sec.  51.1006(a)(1)(ii).
    (3) For any potential control measure identified under paragraph
(a)(2) of this section, the state may make a demonstration that such
measure is not technologically or economically feasible to implement in
whole or in part by the end of the sixth calendar year following the
effective date of designation of the area, and the state may eliminate
such whole or partial measure from further consideration under this
paragraph.
    (i) For purposes of evaluating the technological feasibility of a
potential control measure, the state may consider factors including but
not limited to a source's processes and operating procedures, raw
materials, physical plant layout, and potential environmental impacts
such as increased water pollution, waste disposal, and energy
requirements.
    (ii) For purposes of evaluating the economic feasibility of a
potential control measure, the state may consider factors including but
not limited to capital costs, operating and maintenance costs, and cost
effectiveness of the measure.
    (iii) The state must submit to the EPA as part of its Moderate area
attainment plan a detailed written justification for eliminating from
further consideration any potential control measure identified under
paragraph (a)(2) of this section on the basis of technological or
economic infeasibility.
    (4) The state shall use air quality modeling that meets the
requirements of Sec.  51.1011(a) and that accounts for emissions
reductions estimated due to all technologically and economically
feasible control measures identified for sources of direct
PM2.5 emissions and sources of emissions of PM2.5
plan precursors in the Moderate PM2.5 nonattainment area to
demonstrate that the area can attain the applicable PM2.5
NAAQS as expeditiously as practicable but no later than the end of the
sixth year following the effective date of designation of the area. The
state may use air quality modeling to demonstrate that the Moderate
PM2.5 nonattainment

area cannot practicably attain the applicable PM2.5 NAAQS by
such date.
    (i) If the state demonstrates through air quality modeling that the
area can attain the applicable PM2.5 NAAQS by the end of the
sixth calendar year following the effective date of designation of the
area, the state shall adopt and implement all technologically and
economically feasible control measures identified under paragraph
(a)(3) of this section that are necessary to bring the area into
attainment by such date. The state shall also adopt and implement all
other technologically and economically feasible measures identified
under paragraph (a)(3) of this section that, when considered
collectively, would advance the attainment date for the area by at
least 1 year. If the state demonstrates through this analysis that
control measures for reducing emissions of a PM2.5 precursor
would not be necessary for attainment as expeditiously as practicable
or to advance the attainment date, then the state would not be required
to include control measures for the precursor in the Moderate area
attainment plan, nor be required to address the precursor in the RFP
plan, quantitative milestones and associated reports, and contingency
measures.
    (A) Any control measure identified for adoption and implementation
under this paragraph that can be implemented in whole or in part by 4
years after the effective date of designation of the Moderate
PM2.5 nonattainment area shall be considered RACM for the
area. Any such control measure that is also a control technology shall
be considered RACT for the area.
    (B) Any control measure identified for adoption and implementation
under this paragraph that can only be implemented in whole or in part
during the period beginning 4 years after the effective date of
designation of the Moderate PM2.5 nonattainment area and the
applicable attainment date for the area shall be considered an
additional reasonable measure for the area.
    (ii) If the state demonstrates that the area cannot practicably
attain the applicable PM2.5 NAAQS by the end of the sixth
calendar year following the effective date of designation of the area,
the state shall adopt all technologically and economically feasible
control measures identified under paragraph (a)(3) of this section.
This requirement also applies to areas that demonstrate pursuant to
section 179B that the plan would be adequate to attain or maintain the
standard but for emissions emanating from outside the United States.
    (A) Any control measure identified for adoption and implementation
under this paragraph that can be implemented in whole or in part by 4
years after the effective date of designation of the Moderate
PM2.5 nonattainment area shall be considered RACM for the
area. Any such control measure that is also a control technology shall
be considered RACT for the area.
    (B) Any control measure identified for adoption and implementation
under this paragraph that can only be implemented in whole or in part
during the period beginning 4 years after the effective date of
designation of the Moderate PM2.5 nonattainment area through
the end of the sixth calendar year following the effective date of
designation of the area shall be considered an additional reasonable
measure for the area.
    (b) The state shall adopt control measures, including control
technologies, on sources of direct PM2.5 emissions and
sources of emissions of PM2.5 plan precursors located within
the state but outside the Moderate PM2.5 nonattainment area
if adopting such control measures is necessary to provide for
attainment of the applicable PM2.5 NAAQS in such area.
    (c) For new or revised source emissions limitations on sources of
direct PM2.5 emissions, the state shall establish such
emission limitations to apply either to the total of the filterable
plus condensable fractions of direct PM2.5, or to filterable
PM2.5 and condensable PM2.5 separately.

Sec.  51.1010  Serious area attainment plan control strategy
requirements.

    (a) The state shall identify, adopt, and implement best available
control measures, including control technologies, on sources of direct
PM2.5 emissions and sources of emissions of PM2.5
plan precursors located in any Serious PM2.5 nonattainment
area or portion thereof located within the state and consistent with
the following:
    (1) The state shall identify all sources of direct PM2.5
emissions and all sources of emissions of PM2.5 precursors
in the nonattainment area in accordance with the emissions inventory
requirements of Sec.  51.1008(b).
    (2) The state shall identify all potential control measures to
reduce emissions from all sources of direct PM2.5 emissions
and sources of emissions of PM2.5 plan precursors in the
nonattainment area identified under paragraph (a)(1) of this section.
    (i) The state shall survey other NAAQS nonattainment areas in the
U.S. and identify any measures for direct PM2.5 and