Comment:  One commenter noted that the guidance for “technical
feasibility” implies that States look at individual sources with a
BACT-like case-by-case analysis.  The commenter recommended that source
owners conduct such a site-specific analysis and submit the analysis to
the State through the permitting process.

	Response:    While the analytical analysis to identify RACT is similar
to BACT, as noted above, EPA in the past has issued CTGs that describe
the presumptive norm for RACT controls for a given industry, but that
allow for case-by-case considerations for a given source.  Where States
wished to require source owners to conduct such a site-specific analysis
as part of the control technology review, EPA supports this type of
process.  On the other hand, EPA does not believe it would be
appropriate to require all RACT-eligible sources to conduct such an
analysis, given that States have the primary responsibility for
identifying and analyzing measures for such sources.

5.  What factors should States consider in determining whether an
available control technology or measure is economically feasible? tc
"7.What factors should States consider in determining whether an
available control technology is economically feasible? " \l 3

a. Background.

	In the preamble to the proposed rule, EPA includedThe follow provides
guidance for States to consider in determining whether an available
control technology is economically feasible for purposes of identifying
reasonably available control measures.  We include this guidance in this
preamble as well, with modificationsThis guidance is slightly modified
from our proposal.

b.   Final Rule.

	 Economic feasibility considers the cost of reducing emissions and the
difference between the cost of the emissions reduction approach at the
particular source and the costs of emissions reduction approaches that
have been implemented at other similar sources.  Absent other
indications, EPA presumes that it is reasonable for similar sources to
bear similar costs of emissions reduction.  Economic feasibility for
RACT purposes is largely determined by evidence that other sources in a
source category have in fact applied the control technology or process
change in question.   Of course, EPA also encourages the development of
innovative measures not previously employed which may also be
technically and economically feasible.

	The 	 Economic feasibility encompasses considerations such as whether
the cost of a potential measure is reasonable considering attainment
needs of the area and the costs of other measures, and whether the cost
of a measure is reasonable for the regulated entity to bear, in light of
benefits.

	While many States generally establish RACT requirements for a category
of sources, the Act does not require the same level of control on all
sources in a category, nor does the Act require that each source be
controlled individually.  Similar sources may have different marginal
costs, profit margins and abilities to pass costs through to the
consumer.  These factors are appropriate to consider in determining
whether a given level of control is appropriate for an individual source
or category of sources.  Accordingly, there is no presumption that a
given source must bear a cost similar to any other source.

	States should consider the capital costs, annualized costs, and cost
effectiveness of an emissions reduction technology should be considered,
and effects on the local economy in determining whether a potential
control measure is reasonable for an area or State.  One available
reference for calculating costs is the EPA Air Pollution Control Cost
Manual, which describes the procedures EPA uses for determining these
costs for stationary sources. The above costs should be determined for
all technologically feasible emission reduction options if such measure
is inherently “reasonably available” (e.g., not absurd or clearly
impractical).   States may give substantial weight to cost effectiveness
in evaluating the economic feasibility of an emission reduction
technology.  The cost effectiveness of a technology is its annualized
cost ($/year) divided by the emissions reduced (i.e., tons/year) which
yields a cost per amount of emission reduction ($/ton).  Cost
effectiveness provides a value for each emission reduction option that
is comparable with other options and other facilities.  Where multiple
control options exist for a given source or source category, States
should consider both the cost effectiveness (dollars per ton) of each
option, and the incremental cost effectiveness per ton between the
options (incremental increase in cost between options divided by the
incremental tons reduced).

With respect to In determining whether a given pollutant, a measure is
likely to be reasonable if it has a cost, States may consider costs per
ton similar toof other measures previously employed forto reduce that
pollutant.  In addition, a measure is likely to be reasonable from a
cost effectiveness standpoint if it has a cost per ton similar to that
of other measures needed to achieve expeditious attainment in the area
within the act’s time frames, but similar costs are not conclusive.
As discussed above, States may evaluate equity considerations in
weighing the economic feasibility of imposing a measure on a given
source or source category.

The fact that a measure has been adopted or is in the process of being
adopted by other states is an indicator (though not a definitive one)
that the measure may be technically and economically feasible for
another State.  We anticipate that States may decide upon RACT and RACM
controls that differ from State to State, based on the State’s
determination of the most effective strategies given the relevant
mixture of sources and potential controls in the relevant nonattainment
areas, and differences in the difficulty attaining expeditiously.
Nevertheless, States should consider and address RACT and RACM measures
developed for other areas or other States as part of a well reasoned
RACT and RACM analysis.  The EPA’s own evaluation of State SIPs for
compliance with the RACT and RACM requirements will include comparison
of measures considered or adopted by other States.of reaching
attainment.

	In considering what level of control is reasonable, EPA is not
proposing a fixed dollar per ton cost threshold for RACT, consistent
with the views of multiple commenters.  Areas with more serious air
quality problems typically will need to obtain greater levels of
emissions reductions from local sources than areas with less serious
problems, and it would be expected that their residents could realize
greater health benefits from attaining the standard.  For these reasons,
we believe that it will be reasonable and appropriate for areas with
more serious air quality problems and higher design values to impose
emission reduction requirements with generally higher costs per ton of
reduced emissions than the cost of emissions reductions in areas with
lower design values.  In addition, where.  Where essential reductions
are more difficult to achieve (e.g., because many sources are already
controlled), the cost per ton of control may necessarily be higher.

We believe that in determining appropriate emission control levels, the
State should consider the collective health benefits that can be
realized in the area due to projected improvements in air quality.  The
health benefits associated with reducing PM2.5 levels are significant.
Using estimation techniques reviewed and deemed reasonable by the
National Academy of Sciences, national monetized health benefits
resulting from reductions in PM concentrations are estimated to exceed
emission control costs by a factor of three to thirty times, depending
on the particular controls on sources of PM and precursor emissions.10
This approach is consistent with EPA’s selection of option 2 for the
interpretation of the RACT requirement for PM2.5, i.e., that RACT is
related to what is needed for attainment.  That is, because EPA
concludes that RACT requirement will be met where the State demonstrates
timely attainment, and areas with more severe air quality problems
typically will need to adopt more stringent controls, RACT level
controls in such areas will require controls at higher cost
effectiveness levels ($/ton) than areas with less severe air quality
problem

It is not appropriate to assume that the same cost per ton range is
reasonable for direct PM2.5 and different precursors, because an equal
amount of emission reduction in different pollutants has a different
impact on PM2.5 ambient levels.  For example, in a given nonattainment
area, reductions of direct PM2.5 emissions may prove more expensive than
reductions of Nox emissions, but the resulting benefits of reductions of
direct PM2.5 might warrant the higher costs.  A State should consider
this differential impact on ambient PM2.5 in considering the cost per
ton that is reasonable for controlling different pollutants.  During the
SIP process, States and regional planning organizations typically
conduct sensitivity modeling that can provide this information.  Also,
the forthcoming PM NAAQS RIA will provideprovides information on the
differential impact of PM2.5 and PM precursor reductions on ambient
PM2.5 levels in various areas.

In identifying the range of costs per ton that are reasonable,
information on benefits per ton of emission reduction can be useful as
one factor to consider.  The PM NAAQS RIA will provide information on
the estimated benefits per ton of reducing direct PM2.5 and PM
precursors from various sectors in several analyzed areas.  It should be
noted that such benefits estimates are subject to significant
uncertainties, and that benefits per ton vary in different areas.
Nonetheless this information could be used in a way that recognizes
uncertainties.  If the cost per ton for a measure is significantly less
than the anticipated benefits per ton, this would be a positive
indicator that the cost per ton is reasonable.

One of the factors that could affect estimated compliance costs of an
emission reduction measure is the timing of its implementation.
Hypothetically, if a short compliance period were contemplated for a set
of sources, and if the short compliance period resulted in high demand
for a limited supply of labor or other resources, compliance costs could
be higher than if the same measure were implemented by a later
compliance date.  Should such a situation arise, in considering the
controls that are reasonable, the state should take into account both
the potential for higher costs and the additional health benefits of
achieving the emission reductions sooner rather than later.In such a
case it may be reasonable for the State to find that the measure is
reasonable only if implemented by the later date.

	If a source contends that a source-specific RACT level should be
established because it cannot afford the technology that appears to be
RACT for other sources in its source category, the source should can
support its claim with detailed and verifiedsuch information regarding
the impact of imposing RACT onas:

-- fixed and variable production costs ($/unit),

-- product supply and demand elasticity,

-- product prices (cost absorption vs. cost pass-through),

-- expected costs incurred by competitors,

-- company profits, once the technology or measure is in operation
(considering the annualized costs and the marginal costs of alternative
technologies and measures), ,

-- employment costs., and

-- any other unique factor(s) particular to the individual source.

	Finally, the EPA clarifies that if the State demonstrates through
economic analysis that the imposition of the measure would cause
unacceptable economic disruption for the local economy, that is, a plant
shutdown or a severe curtailment in plant employment or output, a State
may reject the measure as not reasonable to reach attainment as
expeditiously as practicable.

c. Comments and Responses.

	Comment:   Some commenters agreed with EPA’s proposal not to
establish presumptive cost-effectiveness thresholds.

	Response:  The EPA agrees with the commenters.

	Comment:  A number of commenters expressed concerns over the references
to health benefits as a consideration in whether measures are
technically or economically available.   Some commenters believed this
is a consideration not authorized by the CAA.  Others believed that
consideration of benefits, in combination with EPA’s estimates of
benefits per ton, would have the effect of converting RACT to more
stringent LAER levels.  Some commenters expressed concerns whether
States had the resources or expertise to conduct cost-benefit analyses
for this purpose.

	Response:   The EPA wishes to clarify that the reference to health
benefits does not mean that a cost-benefit, or a detailed health
benefits assessment, is a necessary part of a control strategy
demonstration.   We also wish to clarify that EPA is not requiring that
the costs of all technologies and measures for PM2.5 and precursors be
deemed acceptable at any dollar/ton levels at or below the calculated
monetized benefits per ton of reduction.   We do, however, continue to
believe that whetherthe significant benefits associated with PM2.5
ambient reductions generally lead to very high monetized benefits is a
relevant consideration in control strategy development.  We believe that
the general level of benefits is something States and the public should
consider when making decisions on whether to pursue control measures and
technologies.   The EPA disagrees that this limited consideration of
benefits would convert the RACT process to the equivalent of LAER.
This would perhaps be theoretically possible if RACT were an entirely
independent analysis separate from the attainment demonstration, and EPA
took the position that all measures less than a bright-line monetized
benefits cutoff must be selected.     Because RACT, as structured in the
final rule, is inherently linked to the attainment demonstration, and
because as clarified above, the benefits estimates are not to be used as
a “bright line,” we disagree that use of these benefits estimates
could even theoretically convert RACT to LAER. Because RACT is linked to
what is necessary to attain as expeditiously as practicable, we disagree
that any consideration of benefits would convert RACT to LAER.

	Comment:  One commenter objected to EPA’s proposed requirement that
States consider competitive factors such as production costs, demand
elasticity, product prices, and cost incurred by competitors in the
determination of RACT. The commenter believed that this information is
generally not accessible to States or industrial facility owners, and is
not necessary for a RACT determination.

	Response:   The EPA generally disagrees that this type of information
is unavailable.  For example, EPA calculates or reviews this type of
data on a regular basis as part of our work on MACT, NSPS, and other
emissions standards.   A document that describes these types of analyses
and the data used to prepare them is the OAQPS Economic Resource Manual
found at     HYPERLINK "http://www.epa.gov/ttn/ecas/analguid.html"
http://www.epa.gov/ttn/ecas/analguid.html .    EPA believes that this
issue is most relevant to category-wide RACT rules where a source seeks
a case-by-case exemption.   Further, EPA believes most RACT
determinations will be developed through case-by-case analyses rather
than rules affecting entire source categories.  Accordingly, this
analysis likely will be requiredrelevant in relatively few cases.

6.  What specific source categories and control measures should a State
evaluate when determining RACT and RACM for a nonattainment area? tc
"16.What specific source categories and control measures should a State
evaluate when determining RACM for a nonattainment area? " \l 3

a.  Background.

	 Section 172 does not provide a specific list of source categories and
control measures that must be evaluated for RACT and RACM for PM2.5.
However, section 172(c)(3) indicates that the nonattainment area plan
must include a “comprehensive, accurate, current, inventory of actual
emissions from all sources of the relevant pollutant.”  This indicates
that States should look broadly at allthe different types of sources in
the nonattainment area.  We recognize that PM2.5 is a new NAAQS without
a long history of implementation as with  ozone.  Therefore, we included
a list of potential RACM measures in the preamble to the proposed rule,
based upon a review of information about the contribution of various
sources to emissions inventories and a review of potential control
measures for such sources.  We requested comment on the specific sources
and potential control measures recommended for RACM analysis on this
list.   Based on comments received and additional information available
to EPA since the proposal, we have made some changes to the list. We
also refer to this list of  potential “RACT and RACM” measures for
the combined approach to RACT and RACM in the final rule.

	In the preamble to the proposed rule, EPA indicated that due to the
short time available, it does not plan  to develop new control
techniques guidance (CTG) or ACT documents specifically for purposes of
PM2.5 implementation.  The EPA indicated that other information was
available on control technologies, and EPA also indicated its intention
to maintain an updated list of references for new PM2.5 control
technology information.

b. Final rule.

 Emission reduction measures constituting RACM should be determined on
an area-by-area basis.  We believe that a State should consider each of
the measures listed in this section to determine if each measure is
reasonably available in the applicable nonattainment area.  However, we
do not presume that each of these measures is reasonably available in
each nonattainment area.

	We recommend that each State use the list of source categories in this
section as a starting point for identifying potentially available
control strategies (regulatory and voluntary) for a nonattainment area.
States are encouraged and expected to add other potentially available
measures to the list based on its knowledge of the particular universe
of emissions sources in the area and comments from the general public.
We expect that, depending on the potential measure being analyzed, the
State’s degree of evaluation will vary as appropriate.  Detailed
information on emission control technologies is available from a number
of sources.   EPA intends to maintain a website with links to sources of
information for controlling emissions of direct particulate matter and
PM precursors.

	As discussed in section II.J.5. above, EPA recognizes that control
technology guidance for certain source categories has not been updated
for many years.  Section 183(c) of the CAA, which addresses control
technologies to address ozone nonattainment problems, requires EPA to
“revise and update such documents as the Administrator determines
necessary.”  As new or updated information becomes available States
should consider the new information in their RACT determinations.  A
State should consider the new information in any RACT determinations or
certifications that have not been issued by the State as of the time
such updated information becomes available.

Stationary source measures

- Stationary diesel engine retrofit, rebuild or replacement, with
catalyzed particle filter

- New or upgraded emission control requirements for direct PM2.5
emissions at stationary sources (e.g., installation or improved
performance of control devices such as a baghouse or electrostatic
precipitator; revised opacity standard; improved compliance monitoring
methods)

- Improved capture of particulate emissions to increase the amount of
PM2.5 ducted to control devices, and to minimize the amount of PM2.5
emitted to the atmosphere, for example, through roof monitors

- New or upgraded emission controls for PM2.5 precursors at stationary
sources (e.g., SO2 controls such as wet or dry scrubbers, or reduced
sulfur content in fuel; desulfurization of coke oven gas at coke ovens;
improved sulfur recovery at refineries; increasing the recovery
efficiency at sulfuric acid plants)

- Energy efficiency measures to reduce fuel consumption and associated
pollutant emissions (either from local sources or distant power
providers)

- Measures to reduce fugitive dust from industrial sites

Mobile source measures

- Onroad diesel engine retrofits for school buses,11 trucks and transit
buses using EPA-verified technologies

- Nonroad diesel engine retrofit, rebuild or replacement, with catalyzed
particle filter12

- Diesel idling programs for trucks, locomotive, and other mobile
sources13

- Transportation control measures (including those listed in section
108(f) of the CAA as well as other TCMs), as well as other
transportation demand management and transportation systems management
strategies14

- Programs to reduce emissions or accelerate retirement of high emitting
vehicles, boats, and lawn and garden equipment

- Emissions testing and repair/maintenance programs for onroad vehicles

- Emissions testing and repair/maintenance programs for nonroad
heavy-duty vehicles and equipment15

- Programs to expand use of clean burning fuels

- Prohibitions on the sale and use of diesel fuel that exceeds a high
sulfur content

- Low emissions specifications for equipment or fuel used for large
construction contracts, industrial facilities, ship yards, airports, and
public or private vehicle fleets

- Opacity or other emissions standards for “gross-emitting” diesel
equipment or vessels

- Reduce dust from paved and unpaved roads

Area source measures

- New open burning regulations and/or measures to improve program
effectiveness such as programs to reduce or eliminate burning of land
clearing vegetation

- Smoke management programs to minimize emissions from forest and
agricultural burning activities

- Programs to reduce emissions from woodstoves and fireplaces including
outreach programs, curtailments during days with expected high ambient
levels of PM2.5, and programs to encourage replacement of woodstoves
when houses are sold

- Controls on emissions from charbroiling or other commercial cooking
operations

- Reduced solvent usage or solvent substitution (particularly for
organic compounds with 7 carbon atoms or more, such as toluene, xylene,
and trimethyl benzene)

- Reduce dust from construction activities and vacant disturbed areas

Category- Specific Guidelines on innovative approaches.  The EPA has
issued a number of category specific guidelines on approaches to taking
into account innovative approaches to emissions reductions for purposes
of SIPs.   Categories currently covered by these guidelines include: (1)
Electric-sector Energy Efficiency and Renewable Energy Measures (2) Long
Duration Switch Yard Locomotive Idling (3) Long Duration Truck Idling
(4) Clean Diesel Combustion Technology (5)  Commuter Choice Programs.
See http://www.epa.gov/ttn/airinnovations/measure_specific.html

c.  Comments and Responses

Comment:  Some commenters recommended that EPA provide new CTGs or other
control technology review documents for purposes of assisting States to
address PM2.5 and its precursors, because the information in some
current documents is out-dated.

Response: The EPA recognizes that issuance of new or updated CTGs
specifically tailored for PM2.5 would be useful.  Unfortunately,
limitations on time and resources preclude EPA from developing such CTGs
in advance of the SIP submission date.  The EPA cannot delay the
statutorily specified outer date for SIP submission.  However, EPA
believes that there are already many sources of information and guidance
on key source categories.  To the extent that States need to examine
potential control measures for sources never addressed before in any
area or other context for a previous NAAQS, EPA anticipates that it will
work closely with States during the process of plan development and
approval to ensure an appropriate approach.

Comment:  A number of commenters expressed concerns with references to
the STAPPA and ALAPCO Menu of Options document.  Some commenters
believed that this document must be subject to formal review and comment
to ensure appropriate stakeholder input.

Response:  The EPA believes that the Menu of Options update contains
control technology information that States may wish to consider in
developing their PM2.5 SIPs.   The purpose of the document was to
develop “opportunities” for control through a “menu of options”
for States to consider.   As the document notesResponse:  The language
in the final preamble has been changed to refer to a website EPA
maintains that provides access to a variety of information sources
regarding control technologies that may be useful to States to consider
in developing their PM2.5 SIPs.  These links include evaluations
developed by government and nongovernment organizations.  One such
source with potentially useful information is the STAPPA and ALAPCO Menu
of Options.  However, EPA is not specifically recommending that States
adhere to this list of available sources of information during their
evaluation nor is EPA endorsing any of the specific evaluations as being
appropriate in any specific situation.  Rather, we think documents such
as the Menu of Options provide potentially useful ideas.  Specifically,
States willwould need to assess which items on the menu are applicable
in their areas, and will have to assess the costs of applying controls
locally.   Accordingly, there shouldwould be ample opportunity for
public review of the State’s analysis of the local cost and air
quality impacts of any measure listed in the document which is included
in a State’s SIP.  The EPA is not requiring that States adhere to the
list of measures in the Menu of Options.  The EPA does not in any way
mean to imply that the measures in the Menu of Options are presumed to
be RACM, merely that they are potential controls for areas to consider.
 The Menu of Options has no regulatory significance and thus need not be
issued through notice-and-comment rulemaking.  The EPA notes, however,
that the Menu of Options does provide a comprehensive list of potential
sources and measures that should can help inform States in the
development of their plans.  Similarly, our own list of potential
measures is not intended to be a categorical list of measures which
States must adopt, rather it is intended to provide guidance about the
types of sources and measures that States shouldcan consider in
constructing their nonattainment area plans.  The EPA emphasizes that
whether a source category or potential measure is or is not on this list
is simply not dispositiveconclusive as to whether a given measure should
be required to meet is appropriate to consider in the RACT and RACM
requirement.analysis.  That can be determined only through the State’s
development of the nonattainment plan, and EPA’s evaluation of such
plan.

Comment:  A commenter representing the paper industry interpreted the
proposed rule as requiring electrostatic precipitator and tighter
sulfur-in-fuel requirements for the forest products industry.   The
commenter believed that  EPA was creating limits for such without
adequate rulemaking process.

Response:  The EPA disagrees that the listing of control technologies in
the table in the rule creates a “rebuttable presumption.”   Rather,
the table identifies potential opportunities for emissions reductions
which should be reviewed in light of technical and economic feasibility,
and which a State  should consider in a list of possible RACT and RACM
measures for purposes of attaining the standards as expeditiously as
practicable.  The EPA is currently conducting a sector-based approach to
the paper industry.  One of the goals of the sector initiative on pulp
and paper is to work with the industry to identify reductions in SO2 and
PM2.5 that will assist us in meeting the NAAQS, considering facility
locations, magnitude of emissions, emission stream characteristics, and
cost effectiveness of controls.

Comment:  A number of commenters believed that EPA should develop not
only a list of measures to consider for RACM, but should develop a list
of mandatory measures that States should include, particularly for areas
with attainment dates more than 5 years after designation.

Response:  See discussion in section II.D.3 regarding rule requirements
for attainment date extensions and the issue of whether certain measures
should be mandatory in order for an area to receive an extension.

Comment:   Some commenters believed that the list of possible measures
was deficient in not including sources of PM2.5 and PM2.5 precursors
from agricultural sources.  One commenter believed the list is
incomplete without identifying the contribution of ammonia emissions
associated with livestock, poultry, and crop fertilizers.

Response:   The EPA agrees that measures have been identified for
reducing emissions of PM2.5 and other pollutants from agricultural
operations.   Substantial activity is underway to better characterize
emissions and contributions to ambient levels from agricultural
activities.  For example, a number of air quality topics related to
agriculture as discussed on EPA’s website at     HYPERLINK
"http://www.epa.gov/agriculture/tair.html"
http://www.epa.gov/agriculture/tair.html .   The EPA’s list of
potential measures is not intended to be an exhaustive list of measures
for States to consider, and States should evaluate all measures with
potential for reasonable control of emissions that are significant in
their areas.

	Since 2003, EPA and many stakeholders have been interested in
developing a framework to enable CAFOs to pursue superior environmental
performance across all media.  We are aware that today some CAFOs
voluntarily conduct whole-farm audits to evaluate releases of pollutants
to all media through Environmental Management Systems, self-assessment
tools, performance track, ISO 14001 certification, and State-approved
trade offs in meeting regulatory thresholds between air and water that
accomplish the best overall level of environmental protection given
State and local conditions.   The EPA continues to believe the
development of new and emerging technologies offers the potential to
achieve equivalent or greater pollutant reductions than achieved by the
solely effluent guidelines and standards.  Many of these are superior
from a multimedia perspective, and EPA would like to encourage superior
multimedia solutions.  SIPs which need to address ammonia may provide a
unique opportunity to encourage multimedia approaches at CAFOs.  For
example, the addition of animal by-products provides a valuable source
of nutrients for crops, improves soil structure which enhances soil
permeability, and adds valuable organic matter that improves soil
health.  However, inappropriate application can lead to air and water
quality concerns or the improvement of one media at the cost of another.
 Optimal application technologies and rates reduce potential air and
water quality standards violations.  The EPA does not want to discourage
approaches that are superior from a cross media perspective.

	The EPA notes that during the SIP development process at the State
level, members of the public can recommend measures for the State to
consider, and that this will obligate the State to investigate such
controls to determine if they should be RACT or RACM in a given area.
Through this process, EPA anticipates that States with areas that should
implement such measures will do so.   Further discussion regarding
ammonia is provided in section II.A. above regarding
precursors.Response:   As we indicated in the proposal, we included a
list of potential RACM measures in the preamble to the proposed rule,
based upon a review of information about the contribution of various
sources to the emissions inventories and a review of potential control
measures for such sources.  We did not identify emissions from
agricultural sources in this review.  Because ammonia is not presumed to
be a PM2.5 precursor unless identified for a specific area by the State
or EPA, regulation of ammonia emissions from agricultural sources may
not be necessary.

We also note that the agricultural industry presents unique challenges
to regulators given the nature of the emissions source. Moreover, we
currently lack good methods to quantify agricultural emissions, and we
do not fully understand their contribution to nonattainment problems.
We have entered into an agreement with several animal producer sectors
to monitor animal feeding operations to develop better tools to assess
emissions from this industry.  Hopefully, these tools will enhance our
knowledge of agricultural emissions and their contribution to
nonattainment problems, but until emissions from these sources are
better understood, States should apply appropriate deference in
determining whether any specific measure is RACT/RACM for this industry.

	Comment:   Some commenters raised concerns about a statement in the
proposal that “[i]n addressing a nonattainment area having military
training, testing and operational activities occurring within it, the
State should not need to target these activities for emission
reductions.”  Some commenters interpreted this statement as an
exemption from any emission reduction requirements for military sources.

	Response:  The statement in the proposal was not intended as an
exemption for all military activities.  Emissions potentially
contributing to PM2.5 concentrations at military installations originate
from a variety of sources:  basic operational activities (such as power
generation, other fuel combustion, and transportation to and from
residences, offices, and schools); and from field training and testing
activities (such as personnel training, obscurants used in training,
operation of nonroad vehicles and equipment, and related prescribed
burning operations).  EPA believes that in evaluating emissions for a
specific nonattainment area having military activities occurring within
it, the State should consult with DOD for information on the nature of
these activities and their associated emissions.

	With regard to military training activities specifically, such
activities are periodic in nature, and when they do occur, the principal
type of emissions generated by these activities is dust (e.g. inorganic
direct PM emissions) from field operations.  Other pollutants may be
emitted to a lesser degree from certain onroad and nonroad motor
vehicles.  While military training activities may contribute some degree
of primary PM2.5 emissions to certain nonattainment area inventories,
the fugitive dust generated from military training activities is
predominantly comprised of coarse PM rather than fine PM.

	Based on data from the PM2.5 speciation monitoring network operated by
EPA and the States, the contribution of inorganic dust to total PM2.5
mass on an annual average basis is relatively low in most nonattainment
areas, on the order of 0.5 to 1.5 micrograms per cubic meter (generally
10% or less of total PM2.5 mass).  Dust from military training
activities would be a subset of these levels.  Depending on the
available information and specific circumstances for a particular area,
a State could find in its SIP development analyses that direct PM2.5
emissions from military training activities do not significantly
contribute to PM2.5 concentrations in the nonattainment area, and
therefore would not need to target military training activities for
emission reductions in its nonattainment plan.

7.  How should States consider EGU reductions for CAIR in meeting RACT
and /RACM requirements?

a.  Background.

	 In section III.I.11 of the preamble to the proposed rule, we discussed
the nature of the SO2 and NOx RACT obligations of electric generating
unit (EGU) sources in states subject to the CAIR emission reduction
requirements.  The CAIR rulemaking was finalized in March 2005 and
published at 70 FR 25221 (May 12, 2005).  CAIR requires 28 states and
the District of Columbia to significantly reduce emissions of SO2 and/or
NOx.  The 26 jurisdictions in the CAIR PM2.5 region are required to
reduce annual emissions of SO2 and NOx, and the 26 jurisdictions in the
CAIR ozone region are required to reduce seasonal emissions of NOx.
These jurisdictions also have the option of participating in
EPA-administered annual SO2, annual NOx, and seasonal NOx cap-and-trade
programs (the CAIR trading programs) to meet these emission reduction
requirements.  In addition, in March 2006, EPA promulgated a Federal
implementation plan (FIP) to implement CAIR in these jurisdictions until
they have EPA approved CAIR SIPs in place (71 FR 25328, April 28, 2006).
 The FIP adopts, as the control measure, the CAIR trading programs
slightly modified to allow for Federal instead of State implementation.
When fully implemented, CAIR will reduce SO2 emissions in these
jurisdictions by over 70 percent and NOx emissions by over 60 percent
from 2003 levels. This will result in $85 to $100 billion in health
benefits and nearly $2 billion in visibility benefits per year by 2015
and will substantially reduce premature mortality in the eastern United
States. The benefits will continue to grow each year with further
implementation.

	Sources subject to cap-and-trade programs such as the CAIR trading
programs generally have the option of installing emissions control
technology, adopting some other strategy to reduce emissions, or
purchasing emissions allowances and thereby effectively paying other
sources covered by the cap to reduce emissions. In the proposal, we
noted that a number of EGUs expected to be covered by the CAIR trading
programs are located in nonattainment areas. Based on emissions
projections for 2010 and 2015 using the Integrated Planning Model (IPM),
some of these EGUs are expected to comply with CAIR by purchasing
allowances under the trading program and some are expected to comply by
installing emission controls.

	The proposal also described our past experience with the implementation
of the NOx SIP Call and our belief that many power companies will
develop their strategies for complying with CAIR based, in part, on
consultations with State and local air quality officials in order to
address local PM2.5 and ozone attainment planning needs.  The EPA
suggested that consultations on location of CAIR controls would be
timely during State development of the CAIR SIP, which is due in 2006,
prior to the April 2008 deadline for submitting PM2.5 nonattainment area
SIPs.

	The EPA proposed a determination that in states that fulfill their CAIR
SO2 emission reductions entirely through EGU emission reductions (i.e.
without reductions from non-EGU sources or allowing non-EGU sources to
opt-in to the CAIR SO2 trading program), participation in the CAIR SO2
trading program would satisfy the SO2 RACT requirement for the EGU
sources.  The EPA also proposed that in states that fulfill their CAIR
NOx emission reductions entirely through EGU emission reductions, CAIR
would satisfy NOx RACT for the EGU sources, provided that those sources
with existing selective catalytic reduction (SCR) emission control
technology installed on their boilers operate that technology on a
year-round basis beginning in 2009.  Note that direct PM2.5 emissions
are not addressed by the CAIR program, and EPA did not propose any
determination that compliance with CAIR would satisfy RACT for direct
PM2.5 emissions.  The proposal included a discussion of the rationale
for these proposed determinations for SO2 and NOx, and requested
comments on the issue.

b.  Summary of finalFinal rule.

	Based on consideration of the public comments received, the final rule
maintains the determinations for SO2 and NOx RACT as described in the
proposal, and clarifies that, consistent with the SO2 RACT
determination, the NOx RACT determination for PM2.5 may be relied upon
by states subject to CAIR annual NOx and SO2 emission reduction
requirements (i.e. all states in the CAIR PM2.5 region), that achieve
all annual CAIR NOx reductions from EGUs.

Section 51.1010 ofAs discussed in section II.F.2 on our overall policy
for RACT and RACM, we consider an area’s obligation to implement RACT
to be part of the area’s overall RACM obligation – to adopt those
reasonably available measures needed to reach PM2.5 attainment as
expeditiously as practicable.  The final rule also reflects this
combined RACT/RACM approach regarding EGU control obligations under CAIR
and the extent to which meeting CAIR also satisfies a source’s RACT
and RACM requirements for attainment.

Specifically, the final rule providesincludes a presumption that in
States that fulfill their CAIR SO2 emission reduction requirements
entirely through EGU emission reductions (i.e. without reductions from
non-EGU sources or allowing non-EGU sources to opt in to the CAIR SO2
trading program), compliance by EGU sources with an EPA-approved CAIR
SIP or a CAIR FIP would satisfy the SO2 RACT requirement their SO2
RACT/RACM requirements for attaining the sources.fine particle NAAQS.
This section also providesincludes a presumption that in States that are
subject to CAIR annual NOx emission reduction requirements and fulfill
these requirements entirely through EGU emission reductions (i.e.
without reductions from non-EGU sources or allowing non-EGU sources to
opt in to the CAIR annual NOx trading program), compliance by EGU
sources with an EPA-approved CAIR SIP or a CAIR FIP would satisfy the
NOx RACT/RACM requirement for the sourcesPM2.5 NAAQS, provided that the
sources with existing selective catalytic reduction (SCR) emission
control technology installed on their boilers operate that technology on
a year-round basis beginning in 2009.  This final position is based on a
number of factors identified in the proposal and reviewed discussed
below.

	As discussed more fully in the CAIR final rulemaking notice, EPA has
set the 2009 and 2010 CAIR caps for SO2 and NOx at a level that will
require EGUs to install emission controls on the maximum total capacity
on which it is feasible to install emission controls by those dates.
The EPA concluded that the CAIR compliance dates represent an aggressive
schedule that reflects the limitations of the labor pool, and
equipment/vendor availability, and need for electrical generation
reliability for installation of emission controls.

	Although the actual SO2 cap does not become effective until 2010, we
have designed (banking( provisions in CAIR so that covered EGUs will
begin to reduce their SO2 emissions almost immediately after CAIR is
finalized, and will continue steadily to reduce their emissions in
anticipation of the 2010 cap and the more stringent cap that becomes
effective in 2015.  The 2015 SO2 and NOx caps are specifically designed
to eliminate all SO2 and NOx emissions from EGUs that are highly cost
effective to control (the first caps represent an interim step toward
that end).  In general, we expect that due to economic considerations
many of the largest-emitting sources will be the first to install SO2
and NOx control technology and that such control technology will
gradually be installed on progressively smaller-emitting sources until
the ultimate cap is reached.

	Many PM2.5 nonattainment areas are projected to achieve significant SO2
and NOx reductions under the CAIR program.  We do not believe that
requiring source-specific RACT/RACM controls on specified EGUs in
nonattainment areas would reduce total SO2 and NOx emissions from
sources covered by CAIR below the regionwide levels that will be
achieved under CAIR alone.  In fact, if states chose to require
smaller-emitting sources in nonattainment areas to meet source-specific
RACT requirements by 2009, they would likely use labor and other
resources that would otherwise be used for emission controls on larger
sources.  Because of economies of scale, more boiler-makers may be
required per megawatt of power generation for smaller units than larger
units.  In this case, the imposition of source-specific RACT on smaller
emitting sources by 2009 could actually reduce the amount of (banking(
that would otherwise occur and result in higher SO2 emissions in 2009 as
compared to the level that would result from implementation of CAIR
aloneNor do we believe that “beyond CAIR” EGU controls for SO2 and
NOx are “reasonably available” control measures for most areas
within the CAIR Region.  Accordingly, most States need not evaluate
additional control measures on EGUs to satisfy RACT/RACM requirements as
explained above.

In any event, the imposition of source-specific control requirements on
a limited number of sources also covered by a cap-and-trade program
would not reduce the total regionwide emissions from sources subject to
the program.  Under a cap-and-trade program such as CAIR, there is a
given number of allowances that equals a given emission level.
Source-specific control requirements may affect the temporal
distribution of emissions (by reducing banking and thus delaying early
reductions) or the spatial distribution of emissions (by moving them
around from one place to another), but it does not affect total
emissions.  If source-specific requirements were targeted at the units
that can be controlled most cost-effectively, then the imposition of
source-specific controls would likely achieve the same result as the
cap-and-trade program.  If not, however, the imposition of
source-specific requirements would make any given level of emission
reduction more costly than it would be under the cap-and-trade program
alone.  Thus, the imposition of source-specific RACT on EGUs covered by
CAIR would not reduce total regionwide emissions, but would likely
achieve the same total emission reductions in a more costly way.

	For the reasons stated above, we are confident that CAIR will provide
substantial and highly cost-effective SO2 and NOx emissions reductions
in most nonattainment areas in the CAIR region, as well as substantial
SO2 and NOx reductions in attainment areas.  Collectively these
regionwide reductions will substantially improve air quality in PM2.5
nonattainment areas in the CAIR region.

In defining RACT, EPA believes that power generation facilities
participating in CAIR in states that achieve all reductions from EGUs
can be treated differently from other sources because of special
attributes of that group of facilities including the unique interrelated
nature of the power supply network, and their participation in the CAIR
program.  Th  EPA is defining RACT for other sources in a manner that
involves assessment of potential emission reduction options and
attainment needs in individual nonattainment areas.  By contrast, for
EGUs subject to our finding, EPA is defining RACT as a particular level
of control independent of attainment needs of the individual area:  the
level of control that results from implementation of CAIR.  Based on the
collective reductions and air quality improvements projected throughout
the CAIR region, and the other considerations described above in this
section, EPA has determined that compliance by EGUs with EPA-approved
CAIR SIPs or CAIR FIPs meeting the requirements discussed above would
meet the SO2 and NOx RACT requirement for participating EGUs located in
PM2.5 nonattainment areas.

The States will need to review sources in other emissions categories
independently in making RACT determinations.  Controls on sources
subject to RACT are an important element in plans to ensure attainment
of the standards as expeditiously as practicable.

EGU controls for expeditious attainment.  As discussed in a previous
section of the preamble, in this final rule RACT is interpreted as being
a part of RACM under section 172(c)(1) of the CAA.  The RACM is the
collection of measures from stationary, mobile, and area sources which
ensure attainment of the standards as expeditiously as practicable.
States need to consider for each area those reasonably available
measures that if adopted would meet the overarching requirement to
attain as expeditiously as practicable.  The controls that would be
considered necessary for expeditious attainment depend to an extent on
the difficulty of attaining the standard in a particular area.

	The EPA cannot rule out the possibility that through its analytical
process a State designing an attainment plan might determine that a
certain nonattainment area (1) cannot attain within 5 years, (2)
contains EGU units that would be feasible and cost effective to control
but would not expeditiously apply controls as a result of CAIR, and (3)
would advance its projected attainment date by at least 1 year if those
nonattainment area units were controlled in the nonattainment SIP as
part of a suite of reasonable measures.  Under this area-specific
analysis, it could be determined that it would be reasonable for certain
EGUs to reduce emissions and advance the attainment date, and in that
event their control would be needed to satisfy the requirements for RACM
and expeditious attainment.  Th  EPA anticipates that these
circumstances could arise in a few areas (e.g., nonattainment areas
where our models project little or no additional emissions reduction due
to CAIR).  For many other areas, analyses may show attainment by 2010
with existing measures, or show that controls for the particular EGUs in
question would not provide a sufficient improvement in local air quality
to advance the attainment date.

In conclusion, and in response to a number of commenters, EPA clarifies
that the RACT and CAIR determinations described above do not inhibit
State and local air agencies from taking actions to attain the standards
as expeditiously as practicable by consulting with power companies and
establishing additional “beyond RACT” emission control requirements
on specific sources in nonattainment areas as necessary to provide for
expeditious attainment.As discussed previously, we are not requiring
that States impose RACT on any specific size or type of source.
Instead, States must conduct a RACT/RACM analysis considering measures
that are “reasonably available” to meet the overarching requirement
to attain the standards as expeditiously as practicable.  Thus,
today’s final rule imposes no specific requirement on States to impose
RACT/RACM on EGUs.

Nonetheless, in evaluating RACT/RACM for EGUs, EPA believes it is
appropriate for States (states that achieve all reductions from EGUs) to
consider the special attributes of that group of facilities including
the unique interrelated nature of the power supply network, and their
participation in the CAIR program.  For EGUs in the CAIR region, based
upon the presumption explained here, States may define RACT/RACM as the
CAIR level of control on the collective group of sources in the region
rather than impose a specific level of control on an individual source.
This approach is similar to the Agency’s past “bubble” policy, as
discussed in section (c) addressing comments on the proposal.

As discussed more fully in the CAIR final rulemaking notice, EPA has set
the 2009 and 2010 CAIR caps for SO2 and NOx at a level that will require
EGUs to install emission controls on the maximum total capacity on which
it is feasible to install emission controls by those dates.  The EPA
concluded that the CAIR compliance dates represent an aggressive
schedule that reflects the limitations of the labor pool, and
equipment/vendor availability, and need for electrical generation
reliability for installation of emission controls.

	Although the actual SO2 cap does not become effective until 2010, we
designed banking provisions in CAIR so that covered EGUs will begin to
reduce their SO2 emissions almost immediately after CAIR is finalized,
and will continue steadily to reduce their emissions in anticipation of
the 2010 cap and the more stringent cap that becomes effective in 2015.
The 2015 SO2 and NOx caps are specifically designed to eliminate all SO2
and NOx emissions from EGUs that are highly cost effective to control
(the first caps represent an interim step toward that end).

Moreover, we predicted that the majority of large coal-fired utilities
will install advanced control technologies under CAIR because the larger
and higher emitting source offer an opportunity to obtain more
cost-effective emissions reductions.  We expect that the
largest-emitting sources will be the first to install SO2 and NOx
control technology and that such control technology will gradually be
installed on progressively smaller-emitting sources until the ultimate
cap is reached.  As a result, few, if any coal-fired units with greater
than 600 MW of operating capacity should operate in PM2.5 nonattainment
areas without advanced control after full implementation of CAIR. Of the
remaining units operating without advanced pollution controls, a great
many of these units will have operating capacities below 300 MW.  We
predict that these units “will be utilized less often,” and
“typically have baghouses and electrostatic precipitators for
particulate control, have combustion controls for NOx control, and burn
low-sulfur coal.”  See “Contributions of CAIR/CAMR/CAVR to NAAQS
Attainment: Focus on Control Technologies and Emission Reductions in the
Electric Power Sector,” Office of Air and Radiation, U.S.
Environmental Protection Agency, April 18, 2006 (available at
http://www.epa.gov/airmarkets/cair/analyses/naaqsattainment.pdf).  In
light of these expected results, we generally believe that the cost to
install additional controls on these smaller units would be
unreasonable.

We are also concerned that if States require specific EGUs to install
advanced pollution control measures, it could interfere with the
market-based incentives inherent in the cap and trade program.  This
could increase the cost of compliance and shift the location of the
units that would otherwise opt to install advanced emissions controls.
Such a result may be counterproductive to that State’s attainment
efforts, as the State may forego a larger quantity of more beneficial
reductions in transported pollutants, in exchange for a smaller quantity
and less beneficial reduction in local emissions.  Moreover, it may
reduce the benefits expected in other nonattainment areas as well.
Accordingly, even if a State found the cost to control an individual
unit acceptable on a cost per ton basis, the potential overall
disbenefit of control may nonetheless make imposition of the control not
“reasonably available.”

	EPA finds that the control installations projected to result from CAIR
NOx and SO2 caps in 2009 and 2010 are as much as feasible from EGUS
across the CAIR Region by those dates.  In fact, if states chose to
require smaller-emitting sources in nonattainment areas to meet
source-specific RACT requirements by 2009, they would likely use labor
and other resources that would otherwise be used for emission controls
on larger sources.  Because of economies of scale, more boiler-makers
may be required per megawatt of power generation for smaller units than
larger units.  In this case, the imposition of source-specific RACT/RACM
on smaller emitting sources by 2009 could actually reduce the amount of
banking that would otherwise occur and result in higher SO2 emissions in
2009 as compared to the level that would result from implementation of
CAIR alone.

In any event, the imposition of source-specific control requirements on
a limited number of sources also covered by a cap-and-trade program
would not reduce the total regionwide emissions from sources subject to
the program.  Under a cap-and-trade program such as CAIR, a given number
of allowances are issued in order to achieve a given emission level.
Source-specific control requirements within the CAIR program may affect
the temporal distribution of emissions (by reducing banking and thus
delaying early reductions) or the spatial distribution of emissions (by
moving them around from one place to another), but they would not affect
total regional emissions under the program.  If source-specific
requirements were targeted at the units that could be controlled most
cost-effectively, then the imposition of source-specific controls would
likely achieve the same result as the cap-and-trade program.  If not,
however, the imposition of source-specific requirements would make any
given level of emission reduction more costly than it would be under the
cap-and-trade program alone.  Thus, the imposition of source-specific
RACT on EGUs covered by CAIR would not reduce total regionwide
emissions, but would likely achieve the same total emission reductions
in a more costly way.

  Given the considerations described above, we think that in many areas
additional controls on EGUs generally would not be “reasonably
available.”  Notwithstanding these conclusions, we recognize that
States are in the best position to determine how best to achieve
attainment with the PM2.5 NAAQS in light of local needs and conditions.
As we acknowledged in our proposed rule, power plant operators typically
have ongoing relationships with the state and local officials involved
in air quality planning.  We expect that power plants will continue to
collaborate with State officials to determine how best to address
multiple air quality goals, and which plant locations to control under
CAIR, considering local PM2.5 and ozone attainment needs.

EPA expects States and local air agencies to identify reasonably
available control measures that are necessary and reasonable to attain
the standards as expeditiously as practicable; and that after consulting
with power companies, the State may conclude that establishing
additional “beyond CAIR” emission control requirements on specific
sources in nonattainment areas is warranted to provide for attainment as
expeditiously as practicable.  Nevertheless, in preparing the overall
attainment demonstration, States should be aware of the expected
benefits of the market-based incentives of the CAIR program, the cost
effectiveness of control, feasibility of implementation, and any
disbenefits that would result from requiring “beyond CAIR” controls
on any specific EGU before concluding that addition controls on EGUs are
“reasonably available” and necessary to satisfy RACT/RACM
requirements.

	Year-round NOx controls.  In the CAIR final rulemaking notice, EPA
found that the operation of existing SCRs on a year-round basis, instead
of operating them only during the ozone season, could achieve NOx
reductions at low cost relative to other available NOx controls.  The
EPA projected that power generators would employ this control measure to
comply with CAIR SIPs.  Based on this control opportunity, EPA estimated
the average cost of non-ozone-season NOx control at $500/ton.  These
considerations support a finding that RACT should include year-round
operation of EGUexisting SCRs that are located in PM2.5 nonattainment
areas.  Because all PM2.5 nonattainment areas violate the annual form of
the PM2.5 standard and public health can be affected by high PM2.5
levels in the winter as well as the summer, we believe that year-round
operation of existing SCR that are located in nonattainment areas where
NOx is a nonattainment plan precursor will provide additional health
benefits for relatively low dollar cost per ton of pollutant reduced.

	In the proposal notice, EPA conditioned its proposed CAIR-RACT
determination on year-round operation as RACT for EGU SCRproposed to
define “existing” SCRs as those units that were in place by the date
of the proposed rule, saying that this cutoff date would avoid
disinventives to install SCR.  For the final rule, we have eliminated
the cutoff date because we believe the reasons for year-round operation
of SCR that are located in nonattainment areas apply equally to SCR
installed before and after the cutoff date.  We do not see a basis for
exempting SCR installed after that date from the year-round operation
proviso.  We have concluded that the concern stated in the proposal
notice about potential disincentives for SCR installation was misplaced,
because the CAIR rule annual NOx cap provides generators with financial
incentives to operate in-place SCR year-round.  (November 1, 2005).  We
selected this date rather than the final date to avoid creating an
incentive to delay installation of new SCR.  Today, we finalize our
proposed approach with one clarification.  To avoid confusion over the
proper interpretation of the phrase “in place,” we are clarifying
that an existing SCR is one which is fully installed and capable of
operation by November 1, 2005.

	The CAA requires RACT to be implemented as expeditiously as practicable
(and, in the case of areas without an attainment date extension, no
later than 2009).   Depending on the source, year-round operation of
existing SCR involves either no alteration or relatively minor
alteration (the installation of a bypass duct and dampers) of existing
equipment.  For EGUs where these alterations are needed, we expect, that
most of the work can be done while the unit is operating and that work
that needs to be done while the unit is shut-down can be done during a
normally scheduled maintenance outage.  We also expect that the
materials needed for the modifications are readily available and will
not require significant lead-times for purchase.  Finally, the We also
proposed that these existing SCR begin year-round operations no later
than January 1, 2009 to qualify as RACT/RACM under our presumptive
approach. We noted that year round operation of existing SCR involves
little to no alteration of existing equipment, and that EGUs could
conduct any required work during normal outages.  Today, after taking
these factors into account, we finalize our proposed rule.  The
year-round operation requirement, however, will not be legally
applicablefederally enforceable to individual sources EGUs until EPA
approves a RACTState’s  SIP including the requirement is adopted. We
note that all EGUs in PM2.5 nonattainment areas are on notice from the
date this rule is finalized that SIPs must require year-round operation
of in-place SCRs in order to support a determination that the EGUs in
the area meet RACT.

Taking these factors into account, EPA believes that a January 1, 2009,
implementation date (as proposed) would provide ample lead time to
enable SCRs that currently exist in PM2.5 nonattainment areas to be
operated year-round, including those SCRs for which physical alterations
are necessary.  Also, EPA believes that it is reasonable for EGU SCR
that are installed in PM2.5 nonattainment areas after the date of this
final rule to be operated year-round by January 1, 2009, or the date
they commence operation, whichever is later.  We note that this rule
provides notice of EPA’s NOx RACT determination for nonattainment area
EGU, including the year-round operation proviso for SCR, 27 months in
advance of January 1, 2009.  Therefore, generators installing SCR during
the period between the promulgation date of this final rule and January
1, 2009, should be able either to ensure that the initial design
accommodates year-round operation, or make alterations during an routine
outage, prior to the beginning of 2009.

In summary, EPA is determining that in states that fulfill their CAIR
NOx emission reductions entirely through EGU emission reductions, CAIR
would satisfy NOx RACT for the EGU sources, provided that those
nonattainment-area sources with selective catalytic reduction (SCR)
emission control technology installed on their boilers operate that
technology on a year-round basis by January 1, 2009, or in the case of
SCR installed after that date, the date when SCR operation commences.

c.  Comments and responses

	Comment:  Some commenters supported the proposed determination
described in section (a) that for EGUs located in states in States that
achievefulfill their CAIR SO2 emission reduction requirements entirely
through EGU emission reductions from EGUs only, compliance with CAIR
would satisfy the source’s obligation to meet SO2 and NOx RACT
requirements.(i.e. without reductions from non-EGU sources or allowing
non-EGU sources to opt in to the CAIR SO2 trading program), compliance
by EGU sources with an EPA-approved CAIR SIP or a CAIR FIP would satisfy
the SO2 RACT requirement for the sources; and in States that are subject
to CAIR annual NOx emission reduction requirements and fulfill these
requirements entirely through EGU emission reductions (i.e. without
reductions from non-EGU sources or allowing non-EGU sources to opt in to
the CAIR annual NOx trading program), compliance by EGU sources with an
EPA-approved CAIR SIP or a CAIR FIP would satisfy the NOx RACT
requirement for the sources, provided that the sources with existing
selective catalytic reduction (SCR) emission control technology
installed on their boilers operate that technology on a year-round basis
beginning in 2009.  One commenter supportssupported EPA’s approach so
long as states may pursue additional reductions from EGUs if needed for
expeditious attainment as expeditiously as practicable.  A number of
other commenters opposed the proposed determination regarding RACT for
EGUs based on a number of issues.

	Response:  The EPA agrees with these comments.

	Comment:  A number of commenters agreed with EPA that CAIR will
satisfyBased on the NOx RACT requirement for any EGU with an
SCRrationale described in place and operated year-round by no later than
the beginning of 2009. sections above, the final rule includes a
presumption that compliance with CAIR satisfies SO2 and NOx RACT/RACM
requirements for EGUs in many areas.  Nonetheless, States can require
“beyond CAIR” EGU controls if a State determines that it is a
necessary and reasonable means to attain the PM2.5 standards.  Comments
opposing this approach are addressed in more detail below.

	Response:  The EPA agrees with these comments.

	Comment:  A number of commenters objected to the proposed
determination, arguing that it would result in greater control
requirements and economic burden on non-EGU sources located in
nonattainment areas.  These commenters urged EPA to adopt a final rule
that provides for implementing the most cost-effective controls
necessary to attain the standard.  They assert that with the proposed
finding that compliance with CAIR satisfies RACT for EGUs, the proposed
rule would not provide for the most cost-effective approach to
attainment.  They argue EPA and States should develop cost-effectiveness
guidance that includes all stationary source control measures and they
should develop SIPs based on the most economic means to attain the
standard.  They make several arguments to support this position.  If The
commenters asserted that if an EGU control is more cost-effective than a
non-EGU control, the EGU should be subject to “beyond-CAIR”
controls.  IfThey also asserted that if EPA chooses to callconsider the
CAIR rule equivalent toas satisfying SO2 and NOx RACT for EGUs, then
other sources should not be subjected to control costs greater than
those found reasonable under CAIR (i.e., $800/ton). It  They believe it
would be inequitable to require smaller sources to pay a higher cost for
emissions reductions than larger sources, which are a more significant
contributor to the problem and which may be able to make more
cost-effective emission reductions.  One commenter also suggested that
EPA should authorize a presumption that emissions reductions required on
electric utilities under the CAIR will be equivalent to RACT only if a
particular source in a CAIR State has installed controls that achieve
the average level of control that EPA has projected will occur for the
particular pollutant under the CAIR requirements.

	Response:  The EPA believeshas determined that implementation of the
CAIR trading programs are the mostprogram represents highly
cost-effective methods for achieving controls that will achieve
widespread regional SO2 and NOx emissions reductions from EGUs and for
providingwill provide significant air quality benefits for ozone and
PM2.5 nonattainment areas.  The determination in the final rule that
compliance with a CAIR SIP or FIP may satisfy RACT for EGUs does not
constrain a State from requiring specific sources to install emission
controls in order for an area to attain an air quality standard as
expeditiously as practicable.  In developing attainment SIPs and
identifying RACM, States will need to consider additional cost-effective
and reasonable controls to reach attainment as expeditiously as
practicable.  EPA does not agree with the commenter’s argument that
controls on non-EGUs should be no more than the projected cost of EGU
controls under CAIR.  EPA expects that in order to achieve attainment as
expeditiously as practicable, some states may need to adopt control
measures for some sources which cost more per ton but which still are
considered to be reasonable and cost-effective.

	Comment:  A number of commenters opposed the proposed CAIR=RACT
determination arguing it In addition, States must consider the economic
feasibility of implementing a given control measure.  Because of
facility-specific factors, EPA believes it would be inappropriate to
establish a threshold of control effectiveness (e.g. dollars per ton)
based on control of EGUs and apply this threshold to all source
categories.  The ability of a source to cost-effectively reduce
emissions is dependent on case-specific factors, including the ability
of the given source to sustain the cost of control, and prevailing costs
in the specific geographical location.  A direct correlation between the
size of an emissions source and the economic feasibility of controls for
that source and location does not necessarily exist.

We also disagree with the commenter who suggests that RACT requirements
should only be satisfied if a source achieves an average level of
control that EPA projects to occur under CAIR.  EPA maintains that the
presumption that CAIR satisfies SO2 and NOx RACT/RACM for EGUs in most
areas is an appropriate policy.  As discussed further below, we  have
always recognized that States could determine RACT for a single source
or group of sources.

Comment:  A number of commenters opposed the proposed determination that
CAIR would satisfy the SO2 and NOx RACT requirement for EGU’s.  The
commenters argued that this determination is unlawful, it does not
comply with section 172(c)(1) of the CAA which requires RACT (i.e.
controls that are technologically and economically feasible) “at a
minimum” for all existing sources in the nonattainment area, it would
allow very large stationary sources to escape cost-effective controls
entirely, and it is largely based on the legally-irrelevant contention
that CAIR will reduce emissions more cost-effectively than RACT.  They
claim that EPA has no authority to displace the Congressionally-mandated
RACT requirement, that CAIR was designed to address regional pollution
transport (not to be an attainment strategy), and that EPA should remove
these proposed provisions in the final rule.  Commenters claim that the
EPA(s proposed approach to allow EGU emissions to be addressed solely
through CAIR would undermine states( efforts to meet the Federal PM2.5
health standard, particularly when EGU sources are among the most
cost-effective to control.  Another commenter claimed that EPA’s
proposal allowing states who that choose to fulfill their CAIR
requirements entirely through emission reductions from EGUs to also use
CAIR to satisfy their SO2 and NOx PM2.5 RACT requirements, thereby
equating these two requirements for the EGU sector, is flawed. This
commenter argued that allowing a cap-and-trade program, such as the
CAIR, to substitute for the RACT requirement undermines the
effectiveness of the controls by allowing facilities to use allowances
to offset emissions, rather than control them at the source.  The
Purchasepurchase of an allowanceallowances, they assert, does not
satisifysatisfy RACT requirements.

	Response:  The EPA disagrees with these comments.  The Today’s final
rule does not displace the RACT requirement for any sources.  Instead,
EPA is exercising its authority to interpret the section 172 RACT and
RACM requirements for the purposes of implementing the 1997 PM2.5
standards.  For the reasons described in section (b) above, we believe
that states can rely on EPA’s determination presumption that
compliance with a CAIR SIP or FIP, meeting certain requirements,
satisfieswill satisfy the RACT/RACM requirement for certain EGU sources.
EPA historically issued control technology guidelines setting forth
presumptive levels of emissions control that satisfy the RACT
requirement for a given industry.  Today’s final rule is similar to
this practice in establishing a presumption that SO2 and NOx reductions
under the CAIR program satisfy the RACT/RACM requirement for EGUs in
CAIR states.  In identifying reasonably available control measures to
ensure attainment as expeditiously as practicable, States will need to
take CAIR reductions into account as well as any additional
cost-effective reductions that are technologically and reasonably
available.

We further find that the attempt by many commenters to characterize CAIR
as a strategy to address only regional pollution transport and not an
attainment strategy as overly simplistic.  EPA analyses for CAIR show
that there are significant air quality benefits projected for individual
nonattainment areas as a result of SO2 and NOx reductions across the
multistate CAIR region.  The Act does not prevent States from properly
crediting measures that achieve multiple objectives (e.g. regional
transport or local nonattainment).  Moreover, Section 110(a)(2)(D)
requires SIPs to contain adequate provisions to assure that sources in
the State do not contribute significantly to nonattainment in any other
State.  The CAIR rule is an integral element in meeting the States’
Section 110 attainment obligations.  Accordingly, it is reasonable to
incorporate this consideration in determining what measures qualify as
RACT/RACM.

Finally, EPA does not interpret the provisions of Section 172(c)(1)
related to the RACT requirement as precluding States’ use of a cap and
trade approach as a means of regulating existing sources and achieving
RACT/RACM reductions, especially in light of Congresses’ expressed
authorization to auction emission rights in Section 172(c)(6).

EPA has long recognized that RACT need not apply to individual sources.
As stated earlier, our early guidance on RACT requirements stated that
States could establish RACT for an “individual sources or a group of
sources.” (emphasis added)  See Memo. Strelow (Dec. 1976) and 44 FR
71779.  Importantly, Congress ratified the early interpretations of RACT
and RACM when it enacted the 1990 Amendments. See 42 U.S.C. Section 7515
(Clean Air Act section 193).  Our 1986 emissions trading policy also
recognized a number of advantages offered through application of a
“bubble” approach including faster compliance with RACT limits and
earlier reductions. Moreover, Courts have upheld EPA’s approval of
States’ use of “bubbling” multiple units to meet RACT
requirements.  See e.g. Natural Resources Defense Council v. EPA, 941
F.2d 1207 (finding that EPA need not adhere to a source specific RACT
determination to satisfy RACT requirements and acknowledging EPA’s
special knowledge and expertise in the area.)

	Comment:  The EPA(’s proposal to allow EGU emissions to be addressed
solely through CAIR undermines statesprospectively States( efforts to
meet the Federal PM2.5 health standard.  EGU sources are among the most
cost-effective to control.

	Response:  For the reasons described in section (b) above, EPA believes
that states can rely on EPA’s determination presumption that
compliance with a CAIR SIP or FIP, meeting certain requirements,
satisifies the SO2 and NOx RACT/RACM requirement for certain EGU
sources.  Areas can require “beyond RACTCAIR” EGU controls if
necessarya State determines that it is a necessary and reasonable means
to attain as expeditiously as practicable.

	Comment:  CAIR fails to address the need for short-term reductions in
PM2.5 and precursor emissions on high pollution days.  While RACT
restricts emissions over a 1-hour to 24-hour period, CAIR only provides
for an annual or seasonal cap. Reliance on CAIR therefore fails to
recognize the importance of reducing short-term emissions, which was
recently highlighted by the EPA(s own proposal to tighten the 24-hour
PM2.5 health standard.  Local and short-term adverse air quality effects
of PM2.5, must he addressed in the final rule by requiring RACT for all
major facilities in addition to CAIR.

	Response:  The EPA agrees that the CAIR program is oriented toward
reducing SO2 and NOx emissions in order to reduce air quality
valuesconcentrations on an annual or and seasonal basis.  AllBecause all
PM2.5 nonattainment areas were designated due to violations of the
annual standard.  However, (and the two designated areas in California
also violated the 24-hour standard), the focus of this implementation
rule is attainment of the annual standard.  CAIR approach is projected
to provide significant air quality benefits in 2010 and 2015 for eastern
PM2.5 nonattainment areas on both an annual basis and on a 98th
percentile 24-hour basis..  Since the PM2.5 24-hour standard was revised
in September 2006 from 65 micrograms per cubic meter to 35 micrograms
per cubic meter, EPA recommends that as States develop implementation
plans to address the annual standard, they consider adopting strategies
that also will provide benefits toward attaining the revised 24-hour
standard.

	Comment:  The proposal is silent on the issue of whether EGUs are
subject to direct PM2.5 emissions RACT requirements.  It is critical
that RACT be required for all facilities with respect direct PM2.5
emissions, regardless of a facility(s participation in CAIR.

	Response:  In the final rule and preamble, EPA has clarified that all
EGUs in nonattainment areas are subject to RACT/RACM for direct PM2.5
emissions.  The determination described above applies only to SO2 and
NOx RACT/RACM, not RACT/RACM for direct PM2.5 emissions from EGUs.

	Comment:  The EPA fails to consider the geographical distributional
impacts of the emission reductions.  Equating CAIR with RACT fails to
take into account the substantial contribution that emissions from EGUs
within a nonattainment area may make toward that area(s PM2.5
nonattainment problem.  The EPA does not attempt to explain how such a
generalized determination satisfies RACT for PM2.5.

	Response:  The EPA acknowledges that some EGUs subject to the CAIR
cap-and-trade programs and located in a nonattainment area will not
install emission controls.  However, the determination in the final rule
that CAIR satisfies SO2 and NOx RACT for certain EGUs does not constrain
a State from requiring specific EGU sources to install emission controls
in order for an area to attain an air quality standard as expeditiously
as practicable.  For the reasons described in section (b) above, EPA
believes that states can rely on EPA’s determination that compliance
with a CAIR SIP or FIP, meeting certain requirements, satisifies the
RACT requirement for certain EGU sources.  We believe that these
collective regionwide reductions satisfy the SO2 and NOx RACT
requirements for certain EGUs, but we reiterate that States are not
constrained from seeking further reductions from EGUs in order to meet
the CAA requirement of attainment as expeditiously as practicable.

	Response:  The establishment of recommended levels for RACT/RACM is an
area Congress delegated to the specific expertise of the Agency.  Based
on our analysis, we conclude that the CAIR emissions caps presumptively
represent the level of emissions control achievable through application
of “reasonably available” control technologies.  Nonetheless, in
developing attainment plans, each State will evaluate the impact of
stationary sources located within the nonattainment area in developing
its attainment strategies for the local area.

	Comment:  A few commenters stated that EPA should explain how this
proposal would be implemented for states that request an extension of an
attainment date because attaining in 5 years or less is impracticable;
i.e., whether EPA would still hold to its interpretation that CAIR
equals RACT for EGUs and not require additional reductions from EGUs
even if an area can(not attain in 5 years and controls on EGUs could
lead it to attain more expeditiously.  These commenters argue that, in
considering if additional RACT is needed in states that obtain
extensions of the attainment deadline after 2010, EPA cannot ignore
potential RACT for electric generating units any more than they would be
allowed legally to avoid consideration of any other RACT candidates.
One commenter is particularly concerned that States would not include
EGUs in their RACT determinations and instead require smaller industrial
boilers or process heaters to control emissions.

	Response:  As stated above, the determination in the final rule does
not constrain a State from requiring specific EGU sources to install
emission controls in order for an area to attain the air quality
standard as expeditiously as practicable.  There may be some situations
in which States may need to require controls on specific power plants in
nonattainment areas to meet RACM requirements.	Response:  EPA’s
determination regarding CAIR and RACT is not limited to areas attaining
within five years.  The Agency’s rationale is presented in the
“final rule” section above.  We disagree that the CAIR-RACT
presumptions necessarily shift emission control burdens from EGUs to
smaller industry boilers and process heaters because, in implementing
the RACM requirement, the State may include an evaluation of control
options on those sources as part of their RACT/RACM analyses.  As stated
above, EPA concluded that the CAIR compliance dates represent an
aggressive schedule that reflects the limitations of the labor pool, and
equipment/vendor availability, and need for electrical generation
reliability for installation of emission controls.  Accordingly,
additional controls on EGUs may not be a reasonably available control
measure that can be effectively implemented in a manner that advances an
area’s attainment date.  Nonetheless, States should consider the
economic and technologic feasibility of implementing controls on all
types of sources (stationary, mobile, area)located in the nonattainment
area, given local conditions, in developing attainment plans.

	Comment:  The EPA designated many partial counties nonattainment for
PM2.5 solely because the areas contained EGU emission sources thought to
cause or contribute to violations of the NAAQS.  In implementing
nonattainment plans, it makes sense to consider further control of these
sources, and because they are located in nonattainment areas, the
ability to do so is provided for and legal under the CAA.

	Response:  The EPA designated PM2.5 nonattainment counties because they
either had a violating monitor or they contributed to a nearby air
quality problem.  TheImportantly, EPA designated these areas without
considering the air quality benefits expected in the future from CAIR.
Accordingly, the fact that an EGU is located in a partial county and we
included the partial county in the nonattainment area because we believe
that the EGU was causing or contributing to the nonattainment
violations, does not equate with a finding that more than CAIR is
required to remedy the nonattainment problem.  Nonetheless,   EPA
believes that States should evaluate the impact of stationary sources in
all designated counties, including those partial counties noted by the
commenter, in its assessment of reasonably available control strategies
to ensure attainment as expeditiouslykly as practicable.

	Comment:  The EPA should adopt the Ozone Transport Commission(s (OTC(s)
approach to cap-and-trade programs. When the OTC developed its NOx
Budget Program (which was the basis for EPA(s NOx SIP call and
subsequently CAIR), it assumed that RACT was applied first. Thus the
cap-and-trade program operated in an environment that assumed RACT was
in force, not in lieu of RACT.

	Response:  Under the ozone national ambient air quality standards, NOx
and VOC RACT have been implemented progressively for the past 30 years
or more, prior to development of the NOx SIP call regional control
program.  In contrast, the PM2.5 implementation program is the first
instance in which we have required RACT has been required /RACM
specifically for fine particle pollution.  For this reason, the CAIR
program is not operating with SO2 and NOx RACT limits already in place
for attainment of the PM2.5 standards.  As Nonetheless, as discussed
above, EPA believes that implementation of the CAIR requirements will
provide for substantial progress in attaining the PM2.5 standards, and
that States may in a few areas require additional EGU controlspresume
that RACT/RACM requirements are equal to provide for expeditious
attainmment of the standards.  CAIR level of control.

	Comment: A few commenters stated that EPA should clarify and modify the
part of its proposal that explains why a State cannot rely on EPA’s
determination that CAIR can satisify the NOx RACT requirement for PM2.5
if the State (elect[s] to allow non-EGU sources to voluntarily enter the
EPA-administered CAIR trading program through an opt-in provision in the
CAIR model rule.( (70 FR 66025 col. 3). These commenters believe that
this part of the proposal might be construed to preclude states subject
to both the NOx SIP Call and included in the CAIR region for ozone from
relying on the NOx RACT determination for PM2.5 if the states choose (to
bring their non-CAIR [including non-EGU] NOx SIP Call trading sources
into the CAIR ozone season NOx cap and trade program.  (70 FR 49708,
49728 col. 3)  (August 24, 2005). The commenters assert that EPA gave
states the option of bringing non-EGU NOx SIP Call sources into the CAIR
seasonal NOx trading program  to ensure that non-CAIR sources, including
non- EGUs, that are subject to the NOx SIP Call rule would not be
(stranded,( starting in 2009, by being left in an ozone season NOx
control program with no EGU trading partners.  The commenters argued
that “EGUs should not be penalized, in the form of denial of CAIR =
RACT treatment, as a result of states exercising their option to avoid
financial and compliance difficulties for non-EGUs that otherwise would
be left without allowance trading partners in the EGU sector after the
NOx SIP Call trading program ends in 2008.”  These commenters point to
EPA’s determination in the final Phase 2 ozone implementation rule,
that participation in the CAIR trading programs can satisify NOx RACT
for ozone even if  a State brings non-EGUs in the NOx SIP Call trading
program into the trading program after 2008, see 70 FR 71657 col. 2,
provided the State retains an (EGU [emission] budget under CAIR that is
at least as restrictive as the EGU budget that was set in the State(s
NOx SIP call SIP,( id. At 71658 col. 1. These commenters argue that EPA
should make a similar determination here regarding NOx RACT for purposes
of PM2.5 NAAQS implementation.

Response:  All states with EPA approved CAIR SIPs or subject to a CAIR
FIP implementing the annual NOx emission reduction requirements, and
obtaining those reductions solely from EGUs may rely on EPA’s
determination that CAIR presumptively satisifies NOx RACT/RACM for PM2.5
for these sources.  This determination is unaffected by whether or not a
State permits NOx SIP Call non-EGUs to participate in the CAIR ozone
season trading program.  In the final rule, EPA clarifies thatwe have
included the determinationpresumption that NOx RACT/RACM for PM2.5 is
satisifiedsatisfied for EGUs complying with a CAIR SIP or CAIR FIP
implementing the annual CAIR NOx emission reduction requirements,
remains valid unless (provided the State elects to allow non-EGUs to
opt-in toimplementation of the CAIR NOx annual trading program.
includes EGUs only).

	In the final ozone implementation rule, EPA addressed numerous issues
relating to the transition from the NOx SIP Call to the CAIR ozone
season trading program, including the impact of bringing NOx SIP Call
non-EGUs into the CAIR ozone season trading program.  Commenters
suggestion that these determinations are relevant to this PM2.5
implementation rule ignores the fact that both the NOx SIP Call and the
CAIR ozone season trading program are seasonal, not annual, trading
programs.  The NOx SIP Call EGU and non-EGU budgets are seasonal NOx
budgets and do not address annual NOx emissions.  As discussed above,
PM2.5 levels year-round contribute to an area’s annual average
concentration, and NOx emissions during non-summer months contribute to
nitrate concentrations, which are typically highest in cooler
temperatures.  For these reasons, EPA believes it would be inappropriate
to accept commenters’ suggestion.

8.  What are the required dates for submission and implementation of
RACT?

a. Background.

	The EPA requested comment on a general approach for the dates for
submission and implementation of RACT rules.  The final rule retains the
proposed approach, as described in the following section.

b. Final Rule.

The final rule requires the following:

(1) Date of submission.  States must submit adopted RACT rules to EPA
within 3 years of designation, at the same time as the attainment
demonstration due in April 2008.

(2) Dates for implementation of control measures.  States should also
implement any measures determined to be RACT expeditiously, as required
by section 172.  Implementation of RACT measures should in no case start
later than the beginning of the year before the nominal attainment date.
  For example, if an area has an attainment date of April 2010, then any
required RACT measures should be in place and operating no later than
the beginning of 2009.  This is intended to help provide for clean air
in calendar year 2009.   As discussed in section II.D, if other criteria
are also met, EPA could then grant the area a 1-year attainment date
extension if the air quality level in the 3rd of the 3 years was below
the level of the standard. If the area observes a second year of clean
air, EPA could grant a second 1-year attainment date extension.  In this
case, the 2009 to 2011 period would then be reviewed to assess whether
the area attains the standards.)

(3) Provisions for a demonstration that additional time is needed.
While EPA expects that States will implement required RACT controls by
January 2009 in most situations, there may be cases where additional
time is needed to implement an innovative control measure or to achieve
a greater level of reduction through a phased approach.  If a State has
provided an adequate demonstration showing that an attainment date
extension would be appropriate for an area, then the State may consider
phasing-in certain RACT controls after      January 2009.  The EPA would
allow the implementation of selected RACT controls after January 2009 if
the State can show why additional time is needed for implementation, and
such delayed implementation still would need to be on a schedule that
provides for expeditious attainment.  In no event could the State wait
to implement RACT controls until the last few years prior to the
attainment date without an adequate rationale for why earlier
implementation was not feasible.

c. Comments and Responsesresponses.

Comment: One commenter supported EPA’s position that implementation of
RACT and RACM by January 1, 2009 is necessary to achieve the effect on
air quality for calendar year 2009.

Response:  The EPA agrees with this comment.

Comment:  Some commenters supported allowing for an implementation
schedule that allowed for implementation of RACT and RACM for a time
frame extending beyond 2009.    These commenters favored such an
approach if States provided  an adequate demonstration of why the
measures cannot be implemented earlier.   Commenters noted that a phased
approach to emissions reductions in some cases could lead to additional
reductions that could not occur by 2009.

	Response:  The EPA agrees with these comments.

	Comment:  One commenter believed that so long as a State
demonstatesdemonstrates attainment by 2015, EPA should not require
implementation of any RACT measures.  The commenter further  asserted
that it would be bad policy to require costly emissions reductions
through imposition of RACT on areas expected to attain the standards
through other means by 2015.

	Response:  The EPA disagrees with this comment.  The CAA requires
States to demonstrate that the nonattainment plan will attain the
standards as expeditiously as practicable and must include RACT and
RACM.   The requirement for “reasonable” measures does not require
that any theoretical measure be implemented, but does require
implementation of those reasonable measures which could advance the
attainment date by at least 1 year.  Given the health effects associated
with PM2.5, EPA believes this approach is sound public policy.

9. Which pollutants must be addressed by States in establishing RACT and
RACM limits in their PM2.5 nonattainment plans?

a.   Background.

	 In the proposed rule, and in the final rule as discussed in detail in
section II.A above, EPA discusses the pollutants which States must
address in the nonattainment plans, in particular with respect to RACT,
RACM and NSR.   These pollutants include not only direct PM2.5, but also
gaseous precursors to the formation of PM2.5.  In general, the decisions
that States and EPA make with respect to which precursors are
significant contributors to an area’s PM2.5 nonattainment problem
define the pollutants and sources to be addressed by States in
developing RACT and RACM.

b.   Final rule.

	In the final rule, in establishing RACT and RACM limits, those RACT and
RACM limits must address:

-- direct emissions of PM2.5

-- SO2, a precursor to PM2.5 formation, and

-- NOx, unless a State makes a finding that NOx emissions from sources
in the State do not significantly contribute to the PM2.5 problem in a
given nonattainment area or to other downwind area concerns.

	The EPA generally presumes that RACT and RACM limits are not needed for
ammonia or VOC unless that State or EPA determines otherwise for a given
nonattainment area.  RACT and RACM limits are needed for ammonia if a
State or EPA makes a finding that ammonia emissions significantly
contribute to the PM2.5 problem in a given nonattainment area or to
other downwind area concerns, and thus finds that control of ammonia
would help address the PM2.5 problem.  RACT and RACM limits are needed
for VOC only if a State or EPA makes a finding that VOC emissions
significantly contribute to the PM2.5 problem in a given nonattainment
area or to other downwind area concerns.  (As a point of clarification,
“VOCs,” which are gaseous organic precursors to the chemical
formation of secondary organic aerosol, are treated differently from
semivolatile or nonvolatile organic compounds which are addressed as
directly emitted PM2.5).  Issues related to the finding of
“significant contribution” for these pollutants are discussed in
Section II.A above.

10.  Under the PM2.5 implementation program, when does a State need to
conduct a RACT determination for an applicable source that already has a
RACT, BACT, LAER, or MACT determination in effect? tc "10.Under the
PM2.5 implementation program, does a State need to conduct a RACT
determination for an applicable source that already has a RACT
determination in effect? " \l 3

a.  Background.

	For PM2.5 nonattainment areas, States are required to implement the
RACT requirement to reduce emissions of direct PM2.5 and PM2.5
precursors from applicable sources.  The EPA anticipates that for some
sources located in PM2.5 nonattainment areas, the State would have
previously conducted RACT determinations for VOC or NOx under the 1-hour
ozone standard, or for direct PM10 emissions under the PM10 standards.
Some of the RACT determinations established under these other programs
would be relatively recent while other determinations may be more than
10 years old.  In some cases, a new RACT determination might reach the
conclusion that the preexisting determination is still valid and would
require the installation of similar control technology because the
relevant pollutant was addressed, the same emission points were
reviewed, and the same fundamental control techniques would still have
similar costs.  In other cases, however, a new RACT analysis could
determine, for example, that better technology has become available, and
that cost-effective emission reductions are achievable.

	In the proposed rule, the EPA requested comments on a general approach
to taking prior RACT determinations into account, and within the general
approach, invited comments on two specific questions:  1) should new
RACT determinations be required for all existing determinations that are
older than a specified amount of time (such as 10 years old)?; and 2)
what supporting information should a State be required to submit as part
of its certification to demonstrate that a previous RACT analysis meets
the RACT requirement currently for purposes of the PM2.5 program?

	In the proposed rule, EPA also noted that sources subject to RACT may
also have been subject to other prior technology determinations such as
BACT, LAER or MACT determinations.  The proposed rule requested comment
on approaches to taking these prior technology determinations into
account.

b.  Final rule.

	The EPA has determined that it is appropriate to follow the approach in
the proposed rule, which is described below.  State RACT SIPs for PM2.5
must assure that RACT is met, either through a new RACT determination or
a certification that previously required RACT controls represent RACT
for PM2.5.

Where a State adopted and EPA approved a control measure as RACT for a
pollutant emitted from a specific stationary source or source category
under another NAAQS program, the State may submit as part of its SIP
revision a certification, with appropriate supporting information, that
the previous determination represents a current RACT level of control
for those emissions for purposes of the PM2.5 program.  Otherwise, the
State should revise the SIP to reflect a modified RACT requirement for
specific sources or source categories.

	In cases where the State’s prior RACT analysis under another NAAQS
program concluded that no additional controls were necessary, a new RACT
determination is required for that source.  In cases where the previous
RACT determination did not require any controls on the source, it is
more likely that a new review might find that emission controls are now
economically and technically feasible.  This is because emissions
reductions from a potential control measure are likely to be greater,
and the cost per ton of emission reduction is likely to be lower, than
in the case of a source that previously installed controls to meet RACT
under another program.

	A RACT determination for a source or source category subject to a prior
RACT determination is also required for any pollutants that were not the
subject of the prior RACT determination, but which the State has
determined should be regulated for purposes of PM2.5.   T   EPA advises
that the State should closely review any existing RACT determinations
established under another NAAQS program.  For RACT certifications and
determinations, States are to consider new information that has become
available since the earlier RACT determination.  For example, where
updated information on control technologies is presented as part of
notice-and-comment rulemaking, including a RACT SIP submittal for
sources previously controlled, States (and EPA) must consider the
additional information as part of that rulemaking.   Existing EPA
guidance on control technologies can be used to help inform RACT
decisions.  However, EPA believes it may not be sufficient for a State
to rely on technology guidance that is several years old and issued to
provide recommendations on control measures and levels for a different
NAAQS in evaluating RACT for PM2.5

	With respect to prior technology determinations other than RACT, the
final rule provides that:

	(1) Prior BACT and LAER determinations.  In many cases, but not all,
best available retrofit technology (BACT) or lowest achievable emission
rate (LAER) provisions for new sources would assure at least RACT level
controls on such sources.  The BACT/LAER analyses do not automatically
ensure compliance with RACT since the regulated pollutant or source
applicability may differ and the analyses may be conducted many years
apart.  States may, however, rely on information gathered from prior
BACT or LAER analyses for the purposes of showing that a source has met
RACT to the extent the information remains valid.  We believe that the
same logic holds true for emissions standards for municipal waste
incinerators under CAA section 111(d) and NSR/PSD settlement agreements.
 Where the State is relying on these standards to represent a RACT level
of control, the State should present its analysis with its determination
during the SIP adoption process.

	(2) Compliance with MACT standards affecting VOC.  In situations where
the State has determined VOC to be a significant contributor to PM2.5
formation in an area, compliance with MACT standards may be considered
in VOC RACT determinations.  For VOC sources subject to MACT standards,
States may streamline their RACT analysis by including a discussion of
the MACT controls and relevant factors such as whether VOCs are well
controlled under the relevant MACT air toxics standard, which units at
the facility have MACT controls, and whether any major new developments
in technologies or costs have occurred subsequent to establishment of
the MACT standards.  We believe that there are many VOC sources that are
well controlled (e.g., through add-on controls or through substitution
of non-VOC non-HAP materials for VOC HAP materials) because they are
regulated by the MACT standards, which EPA developed under CAA section
112.  Any source subject to MACT standards must meet a level that is as
stringent as the best-controlled 12 percent of sources in the industry.
Examples of these HAP sources that may effectively control VOC emissions
include organic chemical plants subject to the hazardous organic NESHAP
(HON), pharmaceutical production facilities, and petroleum refineries.16
 We believe that, in many cases, it will be unlikely that States will
identify VOC emission controls more stringent than the MACT standards
that are not prohibitively expensive and are thus unreasonable.  We
noted our view that this will allow States, in many cases, to conclude
that the control measures implemented to meet MACT standards satisfy any
requirement for VOC RACT.

	(3) Compliance with MACT standards affecting PM2.5 emissions.
Compliance with MACT standards may be considered in direct PM2.5 RACT
determinations.  For direct PM2.5 sources subject to MACT standards,
States may streamline their RACT analysis by including a discussion of
the MACT controls and relevant factors such as whether PM2.5 emissions
are well controlled under the relevant MACT air toxics standard, which
units at the facility have MACT controls, and whether any major new
developments in technologies or costs have occurred subsequent to the
MACT standards.  We believe that there are many direct PM2.5 sources
that are well controlled (e.g., through add-on controls that represent
State-of the art measures for PM2.5 reduction) because they are
regulated by the MACT standards which EPA developed under CAA section
112.  For some MACT standards, PM2.5 is used as a surrogate for
achieving MACT for HAPs such as heavy metals.  Any source subject to
MACT standards must meet a level that is as stringent as the
best-controlled 12 percent of sources in the industry.   We believe that
there will be sources for which it will be unlikely that States will
identify emission controls more stringent than the MACT standards that
are not prohibitively expensive and are thus unreasonable.   In
addressing whether a MACT standard represents best controls for PM2.5,
it is important that the State consider all PM2.5 sources at a given
facility and the nature of the PM limit (i.e., whether the limit ensures
control of the fine fraction of particulate matter).   Also, the State
should evaluate the degree of capture of PM2.5-- that is, the amount of
PM2.5 that is collected and sent to a pollution control device in
addition to the efficiency of the device itself.   This evaluation
should consider the PM2.5 emissions reductions that could by achieved by
improving the degree of capture.

	(4) Year-round controls for NOx.  In some cases, sources subject to NOx
RACT for PM will also be subject to controls under the NOx SIP Call.  In
the 8-hour ozone implementation rule, EPA concluded that certain sources
which have installed emission controls to comply with the NOx SIP call
would be deemed to meet NOx RACT for the purposes of the 8-hour ozone
implementation program.  Some of these sources subject to the NOx SIP
call may choose to control NOx emissions only or primarily during the
ozone season.  For purposes of PM2.5, however, EPA concludes that the
operation of emission controls only or primarily during the ozone season
would not constitute RACT for PM2.5 purposes.   Indeed PM2.5 control
programs must address annual average concentrations, and in many areas
nitrate concentrations are generally highest in the winter.  Therefore,
RACT for PM2.5 is year-round operation of controls.  For sources subject
to both the NOx SIP call and NOx RACT for PM, we believe that, in most
cases, the additional costs of running the NOx SIP call controls
year-round would impose only modest, reasonable additional costs and the
cost  effectiveness would be better than the average cost effectiveness
for many other sources subject to PM RACT.   (See further discussion  in
section F.7 above related to EGU sources subject to CAIR requirements
for NOx).

c. Comments and responses.

	Comments:   A number of commenters agreed with the requirement for the
State to conduct a new RACT determination for any source for which the
State’s prior RACT analysis under another NAAQS program concluded that
RACT was defined as no additional controls.  One commenter noted that
for a source having a previous RACT determination for ozone or PM10 to
show that its level of control currently meets RACT for PM2.5 purposes,
the source must provide supporting documentation showing that the
previous RACT determination was based on the same universe of controls
that are “reasonably available” for the source in the present day.

	Response:  The EPA agrees with these comments.

	Comments:  A few commenters recommended that EPA clarify that RACT
determinations resulting only in “operational changes” should be
treated in an equivalent manner as those resulting in no controls.   The
commenters suggested that, unlike “physical modification,” such
operational changes should always be revisited with a new RACT
determination.

	Response:   The EPA does not agree with the implicit recommendation to
impose different RACT review requirements based on the types of control
previously implemented.  Th The EPA believes that a reassessment of RACT
is warranted, irrespective of the type of control previously implemented
that would consider the reasonableness of modifying or adding controls
in the particular circumstances.   Furthermore, we are concerned that
making such a distinction based upon the fairly broad term
“operational change” would be difficult to interpret and implement,
and would invite unnecessary disputes concerning the application of the
term.

	Comment:  Commenters differed on whether new RACT determinations should
be required for all existing determinations made before a specific date,
and on what that date should be.  Some commenters recommended that EPA
allow States to rely on any previous RACT determinations made after
1990, and one commenter recommended that EPA require states to review
only those older than 10-15 years, another recommended 10 years.    One
commenter believed that a 15-year period would be reasonable where
previous controls were installed, to allow for a 15-year amortization of
the cost of those controls.  Other commenters recommended that new RACT
determinations be made for any RACT determinations older than 5 years.
Another commenter recommended that all RACT determinations should be
reviewed.

	Response:  The EPA has not included any specific time frame in the
final rule.  Th  EPA agrees that the more recent the RACT determination,
the greater the probability that technology advances or decreases in
control cost will not have occurred.  At the same time, technology
advances and decreases in control cost can and have occurred frequently.
 Accordingly, we believe it is necessary for States to review whether
such technology advances or decreases in control cost have occurred
before relying on previous RACT determinations.  We do not believe there
is any specific date or age that could be identified after which States
could ensure that no technology advances or decreases in control cost
will have occurred.

	Comment:  A number of commenters expressed concerns with the resources
required to conduct the certifications required by the proposed
approach, and argued that expending the resources required to review and
to certify previous RACT determinations would not be productive.  One
commenter recommended that EPA provide guidance on the previous RACT
categories for which old RACT determinations are believed to be out of
date.  Another commenter asserted that the only possible exception to
the acceptability of previous RACT measures for purposes of the ozone
standards would be when the new RACT is year-round for an existing
ozone-season RACT measure.

	Response:  The EPA believes that the proposed certification approach
strikes an appropriate balance in requiring States to verify whether
previous RACT determinations currently represent an appropriate RACT
level of control for PM2.5 purposes, while stopping short of requiring
an exhaustive re-analysis for all RACT sources.  The EPA believes that
much of the resource concerns expressed in comments were based upon
concerns that VOC sources are very numerous, and that this approach
would require detailed review for these sources.  As noted previously, a
RACT analysis for VOC sources is required only if a State makes a
finding that VOC sources significantly contribute to nonattainment in
the State or to other downwind air quality concerns.  We believe the
commenters likely overestimate the resource implications of the
certification process for prior RACT determinations.  Another mitigating
factor is that many of these same sources would be reviewed for purposes
of implementing the eight-hour ozone standard.  On the other hand, where
a State or EPA determines that it is appropriate to regulate VOC sources
for PM2.5, EPA believes that it likely would be productive to review the
previous determination for such sources, some of which have not been
reviewed for many years.

	Comment:  One commenter believed that EPA should acknowledge detailed
RACT and RACM analyses for the South Coast and San Joaquin Valley in
California prepared during the 1990s for purposes of implementing the
ozone and PM10 standards.   The commenter believes that EPA acceptance
of these determinations as RACT for PM2.5 would enable States to focus
resources on developing new measures needed for attainment.

	Response:  The EPA agrees that States should focus resources on new
technologies and new developments.  At the same time, EPA recognizes
that for most source categories, new technology continues to be
developed, and new information continues to be generated.  Thus, even
recent RACT determinations for a given source category may be outdated.
Hence, the certification approach in the rule for the relevant sources
or source categories is a reasonable approach which is designed to
provide for the type of focused efforts suggested by the commenter.

	Comment:   One commenter believed that a State certification should
only have to identify the existing RACT levels in a SIP and pollutants
affected, but the State should not be required to provide any additional
information.

	Response:   The EPA disagrees with this comment.  EPA believes that
prior technology determinations should be taken into account in the RACT
determination process.  In reviewing existing RACT determinations, the
State should provide supporting information to show that the existing
technology in use should still be considered RACT, or it should show
that there have been technology advances that have occurred since the
previous RACT limits were developed that are technically and
economically feasible and would contribute to timely attainment.

	Comment:  Some commenters supported EPA’s requirement for year-round
operation of NOx pollution control devices as RACT, given that PM2.5 is
an annual standard, while ozone is a summertime problem.

	Response:  The EPA agrees with these comments.

	Comment:   One commenter concluded that BACT and LAER determinations
should be considered to satisfy RACT, regardless of the date they were
made, because BACT and LAER by definition are more stringent than RACT.

	Response:  The EPA disagrees with this comment.  Th  EPA believes that
in many cases, but not all, BACT and LAER would assure RACT level of
controls.  Reasons that BACT and LAER might not satisfy RACT include:
the pollutant of concern could have been different, the applicability
threshold for BACT and LAER may have excluded smaller sources
potentially subject to RACT controls, and technology advances or
reductions in control costs may have occurred since the old
determination was conducted.

	Comment:   One commenter recommended that EPA allow States to use
information gathered from prior BACT or LAER analyses to complete the
RACT determination, as was allowed in the 8-hour ozone NAAQS
implementation rule.

	Response:  The final rule allows for use of such information, to the
extent it remains valid, to inform a certification by the State that
BACT or LAER technology continues to exceed what would currently be
considered RACT.

	Comment:   Some commenters argued that any MACT determination that
controls the pollutants of concern should be more than sufficient to
satisfy RACT.  Some commenters made similar recommendations regarding
specific standards where PM limits were developed as a surrogate for
HAPs, such as the MACT standard for integrated iron and steel mills, the
MACT standard for iron and steel foundries, and the section 129
standards for waste to energy facilities.

	Response:  While agreeing that MACT controls are relevant, the EPA
disagrees that all MACT determinations should be automatically
considered to satisfy RACT.   Reasons include:  a MACT standard aimed at
toxics might not ensure that the relevant PM2.5 pollutant(s) are well
controlled, MACT applicability provisions might have excluded units
potentially subject to RACT, and technology advances or reductions in
control costs might have occurred since EPA conducted the MACT analysis.
 The EPA believes that the State should review whether technology
advances have occurred including available “beyond the MACT floor”
technologies that may be reasonable in the context of RACT for PM2.5
nonattainment, but which were not selected as MACT for purposes of
implementing section 112.  The EPA believes that RACT analyses should
evaluate whether increased capture of PM2.5 could be achieved, and
whether an increased efficiency in controlling the fine fraction of
particulate matter is reasonably available.   The EPA has, however,
added a specific recognition that MACT standards can reduce PM2.5 as
well as VOC, and that PM2.5 information gathered for MACT standards
development may inform a State’s conclusions on available technologies
for direct PM2.5 emissions.

	Comment:  One commenter expressed a concern that EPA should not presume
that MACT represents RACT where the MACT rule allows for a risk-based
exemption from the control technology requirement.

	Response:  The EPA agrees with this comment.

11.	How should condensable emissions be treated in RACT determinations?
tc "8.How should condensable emissions be treated in RACT
determinations? " \l 3

a.  Background.

	Certain commercial or industrial activities involving high temperature
processes (fuel combustion, metal processing, cooking operations, etc.)
emit gaseous pollutants into the ambient air which rapidly condense into
particle form.  The constituents of these condensed particles include,
but are not limited to, organic material, sulfuric acid, and metals.  In
general, condensable emissions are taken into account wherever possible
in emission factors used to develop national emission inventories, and
States are required under the consolidated emissions reporting rule
(CERR)17 to report condensable emissions in each inventory revision.
Currently, some States have regulations requiring sources to quantify
condensable emissions and to implement control measures for them, and
others do not.  In 1990, EPA promulgated Method 202 in Appendix M of 40
CFR Part 51 to quantify condensable particulate matter emissions.  In
the proposed rule, EPA discussed and requested comment on issues related
to condensable emissions in RACT determinations.

	In the proposed rule, we noted that EPA is in the process of developing
detailed guidance on a new test method which quantifies and can be used
to characterize the constituents of the PM2.5 emissions including both
the filterable and condensable portion of the emissions stream.   We
also noted that when a source implements either of these test methods
addressing condensable emissions, the State will likely need to revise
the source’s emissions limit to account for those emissions that were
previously unregulated.  For the purposes of determining RACT
applicability and establishing RACT emission limits, EPA indicated in
the proposal that it intends to require the State to adopt the new test
method once EPA issues its detailed guidance.   This guidance would be
for use by all sources within a PM2.5 nonattainment area that are
required to reduce emissions as part of the area’s attainment
strategy.

b.  Final rule.

	Issues and comments related to test method and emissions limit issues
for direct PM2.5 for RACT, including discussion of test methods for
condensables PM2.5, are discussed in section II.L.3 of this preamble.
Th  EPA recognizes that in some cases condensable emissions are more
difficult to control than filterable emissions.  However, condensable
emissions may be assumed to be almost entirely in the 2.5 micrometer
range and smaller, so these emissions are inherently more significant
for PM2.5 than for prior particulate matter standards addressing larger
particles.  Therefore, EPA encourages States to conduct a thorough
evaluation of the potential for reducing condensable emissions when
evaluating potential measures for RACT.

12.  What criteria should be met to ensure effective regulations or
permits to implement RACT and RACM?

a. Final rule.

	After the State has identified a RACT or RACM measure for a particular
nonattainment area, it must then implement that measure through a
legally enforceable mechanism (e.g., such as a regulation or a permit
provision). a State rule approved into the SIP).  The regulation or
permit provision shouldlegally enforceable mechanism must meet four
important criteria.

	First, the baseline emissions from the source or group of sources and
the future year projected emissions shouldmust be quantifiable so that
the projected emissions reductions from the sources can be attributed to
the specific measures being implemented.  It is important that the
emissions from the source category in question are accurately
represented in the baseline inventory so that emissions reductions are
properly calculated.  In particular, it is especially important to
ensure that both the filterable and condensable components of PM2.5 are
accurately represented in the baseline since traditional Federal and
State test methods have not included the condensable component of
particulate matter emissions and have not required particle sizing of
the filterable component.

	Second, the control measures must be enforceable.  This means that they
must specify clear, unambiguous, and measurable requirements.  When
feasible, the measurable requirements for larger emitting facilities
should include periodic source testing to establish the capability of
such facilities to achieve the required emission level.  Additionally,
to verify the continued performance of the control measure, specific
monitoring programs appropriate for the type of control measure employed
and the level of emissions must be included to verify the continued
performance of the control measure.  The control measures and monitoring
program must also have been adopted according to proper legal
procedures.

	Third, the measures should must be replicable.  This means that where a
rule contains procedures for interpreting, changing, or determining
compliance with the rule, the procedures are sufficiently specific and
nonsubjective so that two independent entities applying the procedures
would obtain the same result.

	Fourth, the control measures should must be accountable.  This means,
for example, that source-specific emission limits shouldmust be
permanent and must reflect the assumptions used in the SIP
demonstration.  It also means that the SIP must contain a mechanism
(such as a title V operating permit)establish requirements to track
emission changes at sources and provide for corrective action if
emissions reductions are not achieved according to the plan.

b. Comments and Responses

	Comment:  This	There were no comments on this section.  The language
above is identicalvery similar to thatthe language in the proposal, and
there were no comments.

G.  Reasonable Further Progress (RFP)

1.  Background

	Clean Air Act Section 172(c)(2) requires that nonattainment area plans
“shall require reasonable further progress,” which as defined in
Section 171(1) “means such annual incremental reductions in emissions
of the relevant air pollutant as are required by this part or may
reasonably be required by the Administrator for the purpose of ensuring
attainment of the applicable national ambient air quality standard by
the applicable date.”  This section describes the requirements the
Administrator is establishing for states to achieve reasonable further
progress.

	In general terms, the goal of these RFP requirements is for areas to
achieve generally linear progress toward attainment.  The RFP
requirements were included in the Clean Air Act to assure steady
progress toward attaining air quality standards, as opposed to deferring
implementation of all measures until the end date by which the standard
is to be attained.

2. Requirements for Areas with Attainment Dates of 2010 or Earlier

a.  Background

	EPA proposed in sectionIn 40 CFR 51.1009(b)(1) of the proposed rule,
EPA proposed that a State which submits an implementation plan in April
2008 and that demonstrates that a nonattainmentan area will achieve
attainment- by 2010 (i.e., achieves attainment level emissions during
2009 (and thereby attain the standards in 2010) would not be required to
submit a separate reasonable further progress plan for that area.  The
rationale for this approach is that the period between submittal of the
attainment demonstration and the date for attainment is very limited
(i.e. less than two years), and it would not be practical for the state
to be required to meet any set of interim emission reduction targets
prior to the end of 2009In such cases, EPA proposed that the attainment
demonstration would also be considered to demonstrate that the area is
achieving RFP.

b.  Summary of Final Rule

	In the final rule

	, EPA maintainsis maintaining the approach includeddescribed in the
proposed rule.  An area that demonstrates attainment by 2010 shall will
be considered to have satisfied the RFP requirement and need not submit
any additional material to satisfy the RFP requirement.  EPA shall will
view the attainment demonstration as also demonstrating that the area is
making reasonable further progress toward attainment.

c. Comments and responses

	Comment:  A number of commenters supported EPA’s view that a
demonstration of attainment by 2010 would also demonstrate that the area
is making reasonable further progress toward attainment.  These
commenters asserted that the timetable for adoption of control measures
would not allow for adoption of additional measures any sooner that
would yield more rapid progress toward attainment.

	Response:  EPA agrees with these comments.  appreciates the support and
is adopting the supported approach.

	Comment:  A set of commenters characterize EPA’s approach as assuming
that adequate interim progress is already being made in areas that
purport to demonstrate attainment, and they assert that this policy
unlawfully waives the RFP requirement for an area demonstrating
attainment by 2010.  The commenters object to a “blanket finding of
compliance with RFP requirements for any area submitting a SIP that
purports to demonstrate attainment by 2010,” noting that a SIP that
provides no annual reductions or even allows interim increases should
not be considered to meet RFP simply by virtue of a purported attainment
demonstration.  The commenters object to EPA allowing areas to avoid any
interim progress, let alone the linear progress that EPA has
historically required.  These commenters state that a variety of
uncertainties in the attainment process enhances the importance of the
RFP requirement and the accountability that RFP is intended to provide.

	These commenters also claim that PM2.5 nonattainment areas must meet
the requirements of Subpart 4 of Part D of Title I of the Clean Air Act,
including a requirement in Section 189(c) for quantitative progress
milestones to be achieved every 	Comment:  A set of commenters objects
to EPA’s proposal, arguing that EPA cannot waive RFP requirements for
areas where the state purports to demonstrate attainment.  These
commenters believe that Subpart 4 of Part D requires milestones prior to
2009, and these commenters believe that even Subpart 1 requires a
demonstration of interim progress that EPA cannot waive.

	Response:  In brief, EPA is not waiving the RFP requirements for any
area.  Instead, EPA is concluding that a demonstration of attainment by
2010 also serves to demonstrate achievement of RFP.  If the state
submittal purports to demonstrate attainment but does not adequately