conditions. Thus, states are not obligated to consider whether measures
to reduce emissions from wildfires are necessary for reasonable
progress towards natural visibility conditions. However, states may
consider how use of prescribed fire may reduce the frequency,
geographic scale and intensity of natural wildfires, such that vistas
in Class I areas will be clearer on more days of the year, to the
enjoyment of visitors. States may also consider how the use of
prescribed fire on wildland can benefit ecosystem health, protect
public health from the air quality impacts of catastrophic wildfires
and protect against other risks from catastrophic wildfires. Today's
proposals are intended to give states that have considered these
factors, and other relevant factors, the flexibility to provide and
plan for the use of prescribed fire, with basic smoke management
practices applied, to an extent and in a manner that states believe
appropriate. The EPA is committed to working with states, tribes,
federal land managers, other stakeholders and other federal agencies
concerning the use of prescribed fire, as appropriate, to reduce the
impact of wildland fire emissions on visibility.
    Possible effect on the comparison of the RPG to the URP line.
Because wildland wildfires are natural events, emissions from wildland
wildfires do not contribute to ``visibility impairment'' given that
this term refers only to reductions in visibility attributable to
anthropogenic sources. Under the proposed approach of basing RPGs on
the 20 percent most impaired days, we expect that days with large
impacts from wildland wildfires will not be included in the set of days
selected as the 20 percent most

impaired days in each year.\33\ Thus, we expect that wildland wildfires
with notable effects on visibility will not be a reason why a projected
RPG for the 20 percent most impaired days would be above the URP line,
simply because the URP line will be about visibility on other types of
days. Thus, we expect that wildland wildfires will not affect whether a
state becomes subject to the additional analytical requirement to show
that there are no additional measures that are necessary for reasonable
progress. Also, we expect that the 20 percent clearest days (selection
of which is based on visibility as affected by all types of sources)
will not include any days with notable effects from wildland wildfires.
Thus, we expect that wildland wildfires will not affect whether a state
is able to demonstrate that there is no deterioration in visibility on
the 20 percent clearest days, which is a requirement for SIP approval.
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    \33\ We intend to recommend an approach to identifying the 20
percent most impaired days that uses the ambient concentration of
carbon-containing material to separate total light extinction
between natural sources, including wildfires, and anthropogenic
sources. A day strongly affected by wildfire will have high
concentrations of carbon-containing material and a very large
fraction of light extinction will be attributed to natural causes,
thus the day likely will not be one of the 20 percent most impaired
days.
---------------------------------------------------------------------------

Wildland Prescribed Fires

    As anthropogenic events, two issues are associated with prescribed
fires on wildland. The first is whether and how a state is obligated to
consider measures that could reduce emissions from these prescribed
fires as part of a regional required haze program. The second issue is
the possible impact of wildland prescribed fires on whether the RPG is
above the URP line.
    Consideration of control measures for wildland prescribed fire.
Under existing Sec.  51.308(d)(2)(i) and proposed revised Sec.
51.308(f)(2)(v), a state is required to identify all anthropogenic
sources of visibility impairment considered by the state in developing
its long-term strategy and the criteria used to select the sources for
which additional emission reduction measures were considered in light
of the four reasonable progress factors. Existing Sec.
51.308(d)(3)(v)(E) more specifically requires a state to consider
``smoke management techniques for agricultural and forestry management
purposes including plans as currently exist within the State for these
purposes.'' As explained in Section IV.B of this document, in carrying
this paragraph forward into the revision of Sec.  51.308(f) that will
make it free standing, we are proposing to update some of the
terminology and to require states to consider ``basic smoke management
practices for prescribed fire used for agricultural and wildland
vegetation management purposes and smoke management programs as
currently exist within the state for these purposes.''
    Taken together, we interpret these provisions to mean that every
state must consider whether wildland prescribed fires contribute to
impairment at their own Class I areas or Class I areas in other states.
If they do not contribute to any meaningful degree, the SIP may take
note of this and thereby satisfy both provisions. If prescribed fires
in a state contribute meaningfully to impairment at a Class I area, the
state is required to consider basic smoke management practices for
prescribed fires in the development of its long-term strategy,
regardless of whether or not those practices are currently being
implemented, required by state law or mandated by an EPA-approved SIP.
The state would be required to consider only smoke management programs
as currently exist within the state.\34\ We believe that the state
should in this situation give new consideration to the effectiveness of
its smoke management programs in protecting air quality while also
allowing appropriate prescribed fire for ecosystem health and to reduce
the risk of catastrophic wildfires. The state could also consider the
implementation of a new smoke management program.
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    \34\ We interpret ``currently exist'' in both referenced
sections of the Regional Haze Rule to refer to programs that are
operational as of the SIP due date, not the date the Regional Haze
Rule was promulgated.
---------------------------------------------------------------------------

    We would like to make clear that taken together, these two
provisions do not necessarily require any state to ``select'' wildland
prescribed fire (under Sec.  51.308(f)(2)(v)) as an anthropogenic
source of visibility impairment for which it must consider and analyze
emission reduction measures (such as a smoke management program or
basic smoke management practices) based on the four reasonable progress
factors listed in Sec.  51.308(f)(2)(i). Thus, a state is not
necessarily required to develop cost estimates for smoke management
programs or basic smoke management practices. However, if a state does
not ``select'' wildland prescribed fire as a source for four-factor
analysis, it must explain why it has not. As previously stated, the
explanation may be as simple as taking note that prescribed fires do
not make a meaningful contribution to visibility impairment at in-state
and nearby Class I areas. Where prescribed fires are more important, it
may be sufficient for the SIP revision to explain the role of properly
planned and managed wildland prescribed fire as described in this
section, the state's ongoing smoke management programs, if any, and the
current and possibly increased future use of basic smoke management
practices by federal, state, local and private land managers, but not
to ``select'' wildland prescribed fire as a source category for four-
factor analysis.
    If a state does ``select'' wildland prescribed fire as a source for
four-factor analysis, the state must conclude this analysis by
determining whether additional measures to reduce emissions from
wildland prescribed fire are necessary for reasonable progress. Any
such measures must be included in the long-term strategy. Because some
of the basic smoke management practices are difficult to describe with
the specificity needed to make them practically enforceable, it may not
be appropriate to conclude that a SIP requirement for the use of each
practice is necessary for reasonable progress. For example, one basic
smoke management practice is to monitor the effects on air quality due
to the smoke plume from a prescribed fire. ``Monitoring'' could include
ground-based visual observations, aircraft observations, meteorology-
based modeling, fixed or portable air quality monitoring stations,
hand-held monitors, etc. Because the most appropriate monitoring
approach is often situation- and resource-specific, mandating a
specific approach is inadvisable. Therefore, a SIP commitment for a
state or local agency to include the use of basic smoke management
practices could be more desirable than a SIP requirement for land
managers to use each basic smoke management practice.
    Given the benefits of prescribed fires including the reduction they
can achieve in visibility-obscuring smoke from wildfires that affect
visitor's experiences even though not intended to be reflected in the
metrics for tracking progress towards natural visibility conditions, a
state may determine that reasonable progress does not require
implementation of a new or revised smoke management program that
includes an authorization to burn component,\35\ or it may adopt or
revise such a smoke management program. We recommend that a smoke
management program be designed so that it does not inappropriately
restrict prescribed fires with these benefits. If a state determines
that compliance with a smoke

management program of a particular design is required for reasonable
progress, then the state must include the smoke management program in
the SIP as part of the long-term strategy. We believe that states can
include sufficiently detailed, enforceable language in their smoke
management programs to make them practicably enforceable for SIP
purposes (as may not be the case for all basic smoke management
practices). One of the distinguishing elements of a smoke management
program is a provision for periodic program evaluation. We recommend
that every smoke management program include a plan for this periodic
assessment by the responsible authorities that provides for input from
land managers, affected communities and stakeholders. This evaluation
should include an assessment of whether the program is meeting its
goals regarding improving ecosystem health and reducing the damaging
effects of catastrophic wildfires. We are proposing to add to Sec.
51.308(g) a requirement for the periodic progress report on a state's
regional haze program to include a summary of the most recent periodic
assessment of any smoke management program that is part of the long
term strategy.
---------------------------------------------------------------------------

    \35\ See the prior discussion of an authorization to burn
component being one of the six distinguishing features of a ``smoke
management program'' in the context of the Regional Haze Rule.
---------------------------------------------------------------------------

    While the Regional Haze Rule thus does not require regional haze
SIPs to include measures to limit emissions from prescribed fire, it is
not our intention to in any way discourage federal, state, local or
tribal agencies or private land owners from taking situation-
appropriate steps to minimize emissions from prescribed fires on
wildland, or other types of land. The EPA encourages all land owners
and managers to apply appropriate basic smoke management practices to
reduce emissions from prescribed fires. The EPA understands that the
FLMs apply these measures routinely and will be available to consult
with other agencies and private parties interested in doing the same.
    Possible effect on the comparison of the RPG to the URP line.
Prescribed fire on wildlands may contribute to impairment on some of
the days that are among the 20 percent most impaired days. Therefore,
the issue of whether prescribed fires might cause the projected RPG to
be above the URP line is germane.
    Generally, as discussed earlier in this section, we do not expect
the total acreage subject to prescribed fires on wildlands to decrease
in the future because prescribed fire is needed for ecosystem health
and to reduce the risk of catastrophic wildfires.\36\ Thus, the
occurrence of prescribed fire generally will not be projected to
decline towards zero by 2064, nor to decline over any one
implementation period at the proportional rate inherently assumed in
the URP line. In fact, in many areas there may be reason to adopt
policies that facilitate, and accordingly to forecast for purposes of
setting the RPG, more use of prescribed fire and thus higher
contributions to impairment on the 20 percent most impaired days. At
this time, we do not know whether or where such a projected trend may
affect whether the RPG for a Class I area will be above the URP line.
However, we expect that if this is an issue, western Class I areas
would be more likely to be affected.
---------------------------------------------------------------------------

    \36\ See the discussion of climate change effects on wildfire
trends in the preamble to the proposed revisions of the Exceptional
Events Rule. 80 FR 72866-72871, November 20, 2015.
---------------------------------------------------------------------------

    If the projected RPG for a Class I area is above the URP line due
only to the anticipated use of wildland prescribed fire needed for
ecosystem health and to reduce the risk of catastrophic wildfires, we
do not believe that states should expend valuable analytical and
decision making resources on additional analysis of measures necessary
for reasonable progress if basic smoke management practices have been
applied to prescribed fires and the states have otherwise satisfied the
terms of the Regional Haze Rule. Therefore, we are requesting comment
on a proposed provision in Sec.  51.308(f)(1)(vi) that would allow
states with Class I areas significantly impacted by emissions from
wildland prescribed fires to make an adjustment to the URP with
specific approval by the Administrator. The adjustment would consist of
adding to the value of natural visibility conditions an estimate of
wildland prescribed fire impacts, only for the purpose of calculating
the URP and only for prescribed fires that were conducted with the
objective to establish, restore and/or maintain sustainable and
resilient wildland ecosystems, to reduce the risk of catastrophic
wildfires and/or to preserve endangered or threatened species during
which appropriate basic smoke management practices were applied. We
would consider a plan for prescribed fire use on federal, state, tribal
or private lands with this objective that has been reviewed and
certified by the appropriate fire and/or resource management
professionals and agreed to and followed by the land owner/manager to
be sufficient to meet this restriction on the scope of the adjustment
to the URP.\37\ Other evidence of the objective of a prescribed fire
would be considered on a case-by-case basis. We believe that this
adjustment should be permitted only if such prescribed fire impacts
have been estimated with methods and data approved by the Administrator
as scientifically valid.\38\
---------------------------------------------------------------------------

    \37\ Examples of these plans include federal land or resource
management plans, State Forest Action Plans, fire management plans,
prescribed fire on wildland management plans or landscape management
plans.
    \38\ The invitation, in the context of international impacts,
for comment on alternative adjustment approaches also applies to
this proposal regarding an adjustment to account for prescribed fire
impacts. Our recommendation for consultation with other states and
FLMs in the same context also applies to prescribed fire impacts.
---------------------------------------------------------------------------

    We are also proposing changes to fire-related definitions in Sec.
51.301. One of the proposed changes is to remove the term ``prescribed
natural fire'' from the definition of ``fire'' because we consider
prescribed fires to be anthropogenic, although we recognize that some
prescribed fires are intended to emulate and/or mitigate natural
wildfires that would otherwise occur at some point in time. In
addition, we are adding definitions for wildland, wildfire and
prescribed fire. The proposed definitions are consistent with the
definitions we recently proposed for inclusion in the Exceptional
Events Rule.

F. Clarification of and Changes to the Required Content of Progress
Reports

    The EPA believes that additional amendments to Sec.  51.308(g) are
appropriate at this time in order to clarify the substance of the
regional haze progress reports. In its current form, there is ambiguity
in this section with respect to the period to be used for calculating
current visibility conditions, as well as ambiguity with respect to
whether forward-looking, quantitative modeling is required in the
progress reports to assess whether reasonable progress goals will be
met. The EPA wishes to clarify both of these and other issues, and so
proposes to amend Sec.  51.308(g) in the following ways. The EPA seeks
comment on these proposed amendments as well as alternative approaches.
    Section 51.308(g)(3)(ii) is proposed to be amended by adding a
number of explanatory sentences to better indicate what ``current
visibility conditions'' are and how to calculate them. Under the
current version of the rule, it is not clear what ``current visibility
conditions'' are, in part because the term is not defined in Sec.
51.301. Although Sec.  51.308(g)(3) makes reference to 5-year averages
of

annual values for most impaired and least impaired days, and Sec.
51.308(g)(3)(i) requires states to assess current visibility conditions
for the most impaired and least impaired days, there is no clear
indication as to which 5-year average the state should and can
practicably use in a progress report for the current visibility
conditions calculation. For example, the ``current conditions''
terminology does not explicitly allow for the time delay needed for the
IMPROVE network manager to get quality assured data into its database
so they are accessible to the states preparing progress reports.
Practicality requires that ``current conditions'' should mean
``conditions for the most recent period of available data.'' \39\ There
is also an issue of whether this availability is to be determined based
on the start of work on the progress report, the due date for the
progress report, or the actual submission date of the progress report.
The proposed text makes clear that the period for calculating current
visibility conditions is the most recent rolling 5-year period for
which IMPROVE data are available as of a date 6 months preceding the
required date of the progress report. Because we are also proposing
that progress reports no longer be submitted as SIP revisions, meaning
that there would be a much simpler and expeditious state administrative
process to submit a progress report once technical work on it is
completed, we believe that this 6-month period would be sufficient for
states to incorporate the most recent available data into their
progress reports.\40\ The EPA invites comment on other specific
timeframes as the amount of time necessary for states to incorporate
the most recent available data into their progress reports, including 3
months, 9 months and 12 months.
---------------------------------------------------------------------------

    \39\ In our guidance on the preparation of progress reports, the
EPA has indicated that for ``current visibility conditions,'' the
reports should include the 5-year average that includes the most
recent quality assured public data available at the time the state
submits its 5-year progress report for public review. See section
II.C of General Principles for the 5-Year Regional Haze Progress
Reports for the Initial Regional Haze State Implementation Plans,
April 2013.
    \40\ Note that we are not proposing this specification of 6
months for the progress report aspects of a periodic comprehensive
SIP revision (see Section IV.C of this document), in light of the
longer time needed for administrative steps between completion of
technical work and submission to the EPA.
---------------------------------------------------------------------------

    Section 51.308(g)(3)(iii), as currently written, requires a
progress report to contain the value of the change in visibility
impairment for the most and least impaired days over the past 5 years.
This text fails to make clear what the ``past 5 years'' are for
assessing the change in visibility impairment. Because of data
reporting delays, the period covered by available monitoring data will
not line up with the periods defined by the submission dates for
progress reports. Moreover, it is important to ensure that each year of
visibility information is included either in a periodic comprehensive
SIP revision or the progress report that follows it. Therefore, the
``past 5 years'' text is proposed to be deleted and replaced with text
indicating the change in visibility impairment is to be assessed over
the period since the period addressed in the most recent periodic
comprehensive SIP revision.
    The same change to existing ``past 5 years'' text is proposed to be
made to the first sentence of Sec.  51.308(g)(4) for the purposes of
reporting changes in emissions of pollutants contributing to visibility
impairment, for similar reasons. Like monitoring trend summaries,
available emissions trend summaries will not line up with the periods
defined by the submission dates of progress reports. Therefore, the
proposed language removes the ``past 5 years'' text and replaces it
with text indicating the change in emissions of pollutants contributing
to visibility impairment is to be assessed over the period since the
period addressed in the most recent periodic comprehensive SIP
revision.
    The final sentence of Sec.  51.308(g)(4) is proposed to be modified
to revise and clarify the obligation of states regarding emissions
inventories. The current rule text directs the analysis be based on the
``most recent updated emissions inventory,'' with emissions estimates
``projected forward as necessary and appropriate to account for
emissions changes during the applicable 5-year period.'' States are
otherwise required by 40 CFR part 51, subpart A (Air Emissions
Reporting Requirements) to prepare complete emission inventories only
for every third calendar year (2011, 2014, etc.) and to submit these
inventories to the EPA's National Emissions Inventory (NEI). (After
aggregating and quality assuring these submissions, the EPA then
publicly provides summaries of the inventories that have been
submitted.) The current text of Sec.  51.308(g)(4) seemingly requires a
state to ``project'' the most recent of these inventories to the end of
the ``applicable 5-year period'' whenever that end is not the year of a
triennial inventory required by subpart A. Emissions projection is not
a simple or low-resource task even if limited to a projection date that
is in the recent past, as would be the case here. We do not think the
informational value of such projections is in balance with the effort
and time that would be required. At the same time, we believe that
progress reports should present for each significant source sector the
most recently available information, which may be newer for some
sectors than for others. For most sectors, this will be the information
for the triennial year of the most recent NEI submission. However, the
EPA operates a data system that provides information on emissions from
electric generating units (EGUs), which account for a significant
percentage of visibility impairing pollution in many states, with only
a few months lag time. This information comes from reports submitted by
the EGU operators based on continuous emissions monitoring systems.
Therefore, we are proposing text changes that explain clearly the most
recent year through which the emissions analysis must be extended, by
sector. States would be required to include in their progress reports
emissions with respect to all sources and activities up to the
triennial year for which information has already been submitted to the
NEI. With regard to EGUs, states would need to include data up to the
most recent year for which the EPA has provided a state-level summary
of such EGU-reported data. Finally, the last sentence of the proposed
text for this section makes clear that if emission estimation methods
have changed from one reporting year to the next, states need not
backcast, i.e., use the newest methods to repeat the estimation of
emissions in earlier years, in order to create a consistent trend line
over the whole period. The EPA has never expected states to backcast in
this context, but some states have expressed concern that other parties
may interpret the current Regional Haze Rule as requiring such
backcasting. This final change would remove any uncertainty about the
sufficiency of a state's progress report.
    Section 51.308(g)(5) involves assessments of any significant
changes in anthropogenic emissions that have occurred, and is proposed
to be changed in a similar fashion to other sections, deleting the
reference to the ``past 5 years'' and instead directing that the period
to be assessed involves that since the last periodic comprehensive SIP
revision. Text is also proposed to be added that would require states
to report whether these changes were anticipated in the most recent
SIP. Having this explanation within the progress report should not be a
significant burden on the state and will

assist the FLMs, the public and the EPA in understanding the
significance of any change in emissions for the adequacy of the SIP to
achieve established visibility improvement goals.
    The existing Sec.  51.308(g)(6) is proposed to be renumbered as
Sec.  51.308(g)(7). Proposed changes to its provisions regarding
assessment of progress toward meeting reasonable progress goals would
clarify that the reasonable progress goals to be assessed are those
established for the period covered by the most recent periodic
comprehensive SIP revision. This does not change the intended meaning
of this section, and only clarifies that in a progress report, a state
is not required to look forward to visibility conditions beyond the end
of the current implementation period.
    The new Sec.  51.308(g)(6) is proposed to include a provision
requiring a state whose long-term strategy includes a smoke management
program for prescribed fires on wildland to include a summary of the
most recent periodic assessment of the smoke management program
including conclusions that were reached in the assessment as to whether
the program is meeting its goals regarding improving ecosystem health
and reducing the damaging effects of catastrophic wildfires.
    A final proposed change to Sec.  51.308(g) is to remove the
provisions of the existing Sec.  51.308(g)(7) entirely, relieving the
state of the need to review its visibility monitoring strategy within
the context of the progress report. This change was requested by many
states during our pre-proposal consultations, and is appropriate in our
view. Because all states currently rely on their participation in the
IMPROVE monitoring program and expect to continue to do so, continuing
the requirement for every state to submit a distinct monitoring
strategy element in each progress report would consume state and EPA
resources with little or no practical value for visibility protection.
As needed, the EPA will work with involved states and the IMPROVE
Steering Committee to address any needed changes in the visibility
monitoring program.
    It should be noted that minor changes are proposed to Sec.
51.308(h) regarding actions the state is required to take based on the
progress report. These changes merely remove the implication that all
progress reports are to be submitted at 5-year intervals, and improve
public understanding of the declaration that a state must make when it
determines that no SIP revisions are required by removing the word
``negative.'' Minor changes are also proposed to Sec.  51.308(i) in
order to create a stand-alone requirement that states must consult with
FLMs regarding progress reports. This stand-alone requirement is needed
if progress reports are not SIP revisions, because at present the FLM
consultation requirements are applicable only to SIP revisions.

G. Changes to Reasonably Attributable Visibility Impairment Provisions

    The EPA is proposing extensive changes to 40 CFR 51.300 through
51.308 in regard to reasonably attributable visibility impairment. As
discussed in Section III of this document, the reasonably attributable
visibility impairment provisions were originally promulgated in 1980,
when technology for evaluating visibility impairment and its causes was
in its infancy and visual observation of ``plume blight'' was the main
method of determining whether a source was affecting a mandatory Class
I area. Since that time, there have been many advances in ambient
monitoring, emissions quantification, emission control technology and
meteorological and air quality modeling. These advances have been built
into the regional haze program, such that state compliance with the
Regional Haze Rule's requirements will largely ensure that progress is
made towards the goal of natural visibility conditions. Therefore, it
is likely that some aspects of the reasonably attributable visibility
impairment provisions of the visibility regulations have less potential
benefit than they did when they originally took effect over 3 decades
ago. In addition, the reasonably attributable visibility impairment
provisions have received few amendments over the years, including
during amendments made by the Regional Haze Rule in 1999 where the
changes to integrate the reasonably attributable visibility impairment
assessment and mitigation provisions with the new regional haze program
requirements were limited to putting the two separately designed
programs on the same recurring schedule. This has left a substantial
amount of confusing and outdated language within the current visibility
regulations including seemingly overlapping and redundant requirements,
particularly between Sec. Sec.  51.302 and 51.306. Also, as noted in
Section III.A of this document, in actual practice the portion of the
reasonably attributable visibility impairment provisions mandating
periodic assessment of reasonably attributable visibility impairment by
states (or by the EPA in the case of states that do not have an
approved reasonably attributable visibility impairment SIP) has not
resulted in any additional emission control requirements being placed
on emission sources. While there have historically been very few
certifications of existing reasonably attributable visibility
impairment by an FLM, in several situations a certification by an FLM
has ultimately resulted in new controls or changes in source operation.
    The EPA therefore believes it is time to bring clarity to the
reasonably attributable visibility impairment provisions of the rule
and enhance the potential for environmental protection. In brief, our
proposed changes would (1) eliminate recurring requirements on states
that we believe have no significant benefit for visibility protection;
\41\ (2) clarify and strengthen the existing provisions under which
states must address reasonably attributable visibility impairment when
an FLM certifies that such impairment is occurring in a particular
Class I area due to a single source or a small number of sources; (3)
remove existing FIP provisions that require the EPA to periodically
assess whether reasonably attributable visibility impairment is
occurring and to respond to FLM certifications; and (4) edit various
portions of Sec. Sec.  51.300-308 to make them clearer and more
compatible with each other. The substantive and clarifying changes are
described in the following discussion in order of section number. The
EPA seeks comment on each of the following proposed changes, as well as
suggestions for alternative approaches to modernizing the reasonably
attributable visibility impairment provisions.
---------------------------------------------------------------------------

    \41\ These changes, when finalized, would mean that those states
with SIPs that commit them to periodically assess whether reasonably
attributable visibility impairment is occurring at their Class I
areas could remove that commitment from their SIPs.
---------------------------------------------------------------------------

    The EPA is proposing to amend Sec.  51.300, Purpose and
applicability, to expand the reasonably attributable visibility
impairment requirements to all states and territories, with the
exceptions of Guam, Puerto Rico, American Samoa and the Northern
Mariana Islands. These territories have no mandatory Class I areas and
are sufficiently far from other Class I areas to have no anticipated
impact on visibility in such areas. Under our proposal, the geographic
coverage of the reasonably attributable visibility impairment
provisions and the regional haze provisions would be the same. The EPA
believes these changes would strengthen the visibility program and are
appropriate in light of the evolved understanding that pollutants
emitted

from one or a small number of sources can affect Class I areas many
miles away. In other words, emissions occurring in states without Class
I areas can affect downwind states with Class I areas. This proposed
change would provide these areas with additional protection from
reasonably attributable visibility impairment.
    The EPA is proposing to amend Sec.  51.301, Definitions, to change
the definition of reasonably attributable. The current definition of
reasonably attributable is ``attributable by visual observation or any
other technique the State deems appropriate.'' We are proposing to
modify this definition to read ``attributable by visual observation or
any other appropriate technique.'' This change would remove the current
implication that only a state can determine what techniques are
appropriate, even though the FLMs are charged with certifying
reasonably attributable visibility impairment. The proposed change
would make it clear that a state does not have complete discretion to
determine what techniques are appropriate for attributing visibility
impairment to specific sources. It is appropriate that the EPA be able
to review the technique(s) that an FLM has relied upon to determine
that reasonably attributable visibility impairment is occurring, in
light of the views and supporting information provided by both the FLM
and the state. While these views and supporting information, regardless
of whether provided by the FLM or by the state, will not be presumptive
in EPA's ultimate determination as to whether any attribution technique
used is appropriate, the universe of potentially appropriate
attribution techniques is not limited to only those techniques that may
have been utilized during past reasonably attributable visibility
impairment certifications or that have been previously recommended or
discussed via EPA guidance or actions. Rather, the aforementioned
advances in ambient monitoring, emissions quantification, emission
control technology and meteorological and air quality modeling that
have occurred in the decades since 1980 make clear that modeling is one
possible technique for determining that reasonably attributable
visibility impairment is occurring.
    Due to the confusing, and in large part outdated, content of Sec.
51.302, the EPA is proposing to delete the entire text of this section
and replace it with new language. The new text clearly describes a
state's responsibilities upon receiving a FLM certification of
reasonably attributable visibility impairment.
    The proposed Sec.  51.302(a) involves FLM certification of
reasonably attributable visibility impairment and reads much like the
existing Sec.  51.302(c), with the added language that FLMs would
identify in the certification which single source or small number of
sources is responsible for the reasonably attributable visibility
impairment being certified.\42\ Further, the original reasonably
attributable visibility impairment formulation did not anticipate a
situation where one or a small number of sources in one state could
create impairment of visibility in other state(s). Therefore, proposed
language is included to explain that the FLMs would provide the
certification to the state in which the source or small number of
sources is located, which may not necessarily be the state where the
visibility impairment occurs. The proposed language also addresses the
possible situation that a ``small number of sources'' may be partially
in one state and partially in another, such that a certification might
be addressed to multiple states.
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    \42\ The existing rule text at Sec.  51.302(c)(1) does not
explicitly require the FLM to identify a particular source or small
number of sources as responsible for the reasonably attributable
impairment, but the EPA and the FLMs understand that such
identification should be part of a certification. See 45 FR 80086,
``The Federal Land Manager may provide the State with a list of
sources suspected of causing or contributing to visibility
impairment in the mandatory Class I Federal area.'' Under the
proposed new language of Sec.  51.302(b), if the FLM does not
identify the source or small number of sources causing the
impairment, the certification would not create any obligation on the
state to respond with a SIP revision.
---------------------------------------------------------------------------

    The proposed Sec.  51.302(b) describes the required state action in
response to any FLM reasonably attributable visibility impairment
certification, i.e., regardless of the type of source, namely that a
state shall revise its regional haze implementation plan to include a
determination, based on the four reasonable progress factors set forth
in Sec.  51.308(d)(1)(i)(A), of any controls necessary on the certified
source(s) to make reasonable progress toward natural visibility
conditions in the affected Class I area. This preserves the current
state obligation with much the same wording as in the current section,
including the fact that a certification by an FLM would not create a
definite state obligation to adopt a new control requirement, but
rather only to submit a SIP revision that provides for any controls
necessary for reasonable progress. In some cases, this SIP revision
could be combined with an already required SIP revision. The EPA would
review the responding SIP, and would be available to consult with the
state and the certifying FLM as the state prepares its responding SIP.
It would be the EPA, not the certifying FLM, that would determine
whether the responding SIP is adequate and the response reasonable. The
proposed section further maintains the current requirement that the
state include emissions limitations and schedules for compliance, and
adds the requirement that SIPs include monitoring, recordkeeping and
reporting requirements in order to enforce those emissions limitations.
    The proposed Sec.  51.302(c) addresses those situations where an
FLM certifies as a reasonably attributable visibility impairment source
a BART-eligible source where there is at that time no SIP or FIP in
place setting BART emission limits for that source or addressing BART
requirements via a better-than-BART alternative program.\43\ In such an
instance, the proposed rule requires the state to revise its regional
haze SIP to meet the requirements of Sec.  51.308(e), BART requirements
for regional haze visibility impairment, and notes that this
requirement exists in addition to the requirements of Sec.  51.302(b)
regarding imposition of controls for reasonable progress. The new
version of Sec.  51.302(c) clarifies two aspects of the current rule to
match the EPA's past and current interpretations. First, a reasonably
attributable visibility impairment certification for a BART-eligible
source prior to the EPA's approval of a state's BART SIP for that
source does not impose any substantive obligation on a state that is
over and above the BART obligation imposed by Sec.  51.308. However,
the state's response to the reasonably attributable visibility
impairment certification of a BART-eligible source must take into
account current information. This may require a state to update an
analysis prepared earlier in support of a BART SIP that has not been
approved. Second, a reasonably attributable visibility impairment
certification of a BART-eligible source after the state's BART SIP for
that source has been approved by the EPA does not trigger a requirement
for a new BART determination based on the five statutory factors for
BART. Rather, the state's obligation with respect to that source is the
same as for a non-BART eligible source, as stated in the paragraph
immediately earlier. This is

true regardless of how the state's SIP has addressed the BART
requirement for the source, whether through source-specific emission
limits, an alternative better-than-BART analysis, or the special
provisions of Sec.  51.309, which may have not resulted in any new
emission limit for the source.
---------------------------------------------------------------------------

    \43\ Although most of the BART requirements have been addressed
in most states, there remain a handful of states with BART
obligations. In addition, there is litigation over the BART element
in some approved SIPs and promulgated FIPs. We expect that this
situation may exist in one or more states at some time after the
effective date of the final rule.
---------------------------------------------------------------------------

    Regarding the time schedule for state response to an FLM
certification of reasonably attributable visibility impairment, we are
considering a number of possible approaches for the final rule, with
proposed rule text provided for three alternative approaches referred
to as options one, two and three.
    The first alternative proposed rule text at, option one, Sec.
51.302(d) would retain the existing requirement for a state to respond
to a reasonably attributable visibility impairment certification with a
SIP revision within 3 years regardless of when the certification is
made in the cycle of periodic comprehensive SIP revisions.
    The second alternative proposed rule text, option two, at Sec.
51.302(d) would require the state's responsive SIP revision to be
submitted on the due date of the next progress report (but not as part
of the progress report, if the final rule does not require progress
reports themselves to be submitted as SIP revisions) or the next
periodic comprehensive SIP revision, whichever is earlier, provided the
earlier date is at least 2 years after the RAVI certification.
    The third alternative proposed rule text, option three, at Sec.
51.302(d) provides for different deadlines for the state response to
the certification depending on when in the cycle of periodic
comprehensive SIP revisions the reasonably attributable visibility
impairment certification is made. Table 1 provides specific examples of
how application of the third alternative approach in the proposed rule
text would determine due dates for the state response to a
certification.
     If the certification is made more than 2 years prior to
the due date for any periodic comprehensive regional haze SIP revision
required under Sec.  51.308(f) (but, with respect to the SIP due for
the just-prior period, not so early as to be within the 6-month window
described next), then a state must respond to the certification in that
upcoming SIP revision. Failure to respond adequately would prevent full
approval of that SIP revision. If the certification is made more than 2
years before the SIP due date, the state would have more than 2 years
to respond, except as provided in the next bullet.\44\
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    \44\ Under the third alternative proposed rule text, for a
certification made between the 2021 and 2028 SIP due dates, the
state might have up to 6.5 years to respond, assuming the next
bullet does not apply. For a certification made between the 2028 and
2038 due dates, the state might have up to 9.5 years to respond.
---------------------------------------------------------------------------

     If the certification is made less than 2 years prior to
the due date for any periodic comprehensive SIP revision (but no more
than 6 months subsequent to the submission date of that periodic
comprehensive regional haze SIP revision or a SIP revision that amends
a previous submission in a way that affects the emission limits
applicable to the reasonably attributable visibility impairment-
certified source),\45\ then the state must submit a revision to its
regional haze SIP within 2 years from the date of certification. The
EPA believes that in this second timing situation, when the state's
analytical infrastructure has been recently used to prepare a SIP
revision and thus would not be in need of much, if any, refreshment, it
is appropriate to require a responding SIP revision without waiting
longer than 2 years for the next periodic comprehensive SIP revision.
In this timing situation, the EPA would act on the state's standard
regional haze SIP without regard to the not-yet-due obligation for a
reasonably attributable visibility impairment-response SIP revision.
---------------------------------------------------------------------------

    \45\ If a certification is made not too long after a SIP due
date, this parenthetical provision contained in the third
alternative proposed rule text would operate to require the SIP
revision needed to respond to the reasonably attributable visibility
impairment certification to be due sooner than the 6.5 or 9.5 year
extreme noted in the previous footnote.

   Table 1--Example FLM Reasonably Attributable Visibility Impairment
Certification Dates and Corresponding Due Dates for State Response Under
        the Third Alternative Proposed Rule Text (Option Three).
    [All assume submission of a SIP revision by July 31, 2021, unless
                            otherwise noted.]
------------------------------------------------------------------------
                                             Proposed due date for state
         Date of FLM certification                    response
------------------------------------------------------------------------
July 30, 2019.............................  July 31, 2021.
August 1, 2019............................  August 1, 2021.
January 30, 2022..........................  January 30, 2024.
February 1, 2022..........................  July 31, 2028.
April 1, 2022, after late submission of a   April 1, 2024.
 SIP on March 1, 2022.
August 31, 2022, after revised SIP          August 31, 2024.
 submission on July 31, 2021, affecting
 the source identified in the reasonably
 attributable visibility impairment
 certification.
------------------------------------------------------------------------

    The final rule may incorporate any one of these three proposals, or
may combine features of these proposals.
    It is important to note that regardless how the final rule sets the
deadline for the state's responsive SIP revision, if the reasonable
progress goals in the periodic comprehensive regional haze SIP for a
state with a Class I area (and thus required to have reasonable
progress goals in its SIP for that area) have been approved prior to
the approval of its own or a contributing state's separate reasonably
attributable visibility impairment-response SIP, the state would not be
required to revisit and revise its reasonable progress goals to take
into account any additional emission reductions from the certified
source until the next due date for a periodic comprehensive SIP
revision.
    Proposed changes to Sec.  51.303, Exemptions from control, are
minor edits to paragraph (a) designed to

correctly refer to the new Sec.  51.302(c) as well as to the BART
provisions in Sec.  51.308(e). These proposed changes do not alter
which existing facilities may apply to the Administrator for an
exemption from BART. Rather, the proposed changes simply make the
language more clear and direct the reader to the appropriate sections
for reference information.
    Proposed changes to Sec.  51.304, Identification of integral
vistas, are more extensive. An integral vista is defined in Sec.
51.301 as a view perceived from within the Class I area of a specific
landmark or panorama located outside the boundary of the Class I area.
The current version of Sec.  51.304 was written at a time when FLMs
were still in the process of identifying integral vistas. We are
proposing to remove antiquated language in Sec.  51.304 in light of the
fact that FLMs were required to identify any such integral vistas on or
before December 31, 1985. The proposed language would explain this fact
as well as list those few integral vistas that were properly identified
during the applicable time period. States would continue to be subject
to the requirement that these integral vistas be listed in their SIPs.
The EPA notes that the current version of 40 CFR part 51, subpart P is
not perfectly clear on how the existence of an identified integral
vista affects obligations on states and sources, but we are not
proposing any clarification as part of this rulemaking.\46\ We invite
comment on whether all references to integral vistas should be removed
from subpart P, and we may do so in the final rule.
---------------------------------------------------------------------------

    \46\ Section 51.301 states that ``visibility in any mandatory
Class I Federal area includes any integral vista associated with
that area'' but also that ``adverse impact on visibility'' does not
include effects on integral vistas. Section 307(b) requires that
SIPs provide for the review of any new major stationary source or
major modification that may have an impact on any integral vista of
a mandatory Class I Federal area. Other references to ``integral
vista'' are merely definitional or relate to the procedure for
identifying integral vistas.
---------------------------------------------------------------------------

    Proposed changes to Sec.  51.305, Monitoring for reasonably
attributable visibility impairment, involve adding language stating
that the requirement for a state to include in a periodic comprehensive
SIP revision a monitoring strategy specifically for evaluating
reasonably attributable visibility impairment in Class I area(s) only
applies in situations where the Administrator, Regional Administrator
or FLM has advised the state of a need for it. In concept, special
monitoring for reasonably attributable visibility impairment purposes
might be appropriate for a Class I area without an IMPROVE monitoring
station or when the impairment is from a relatively narrow plume such
that the existing IMPROVE monitoring site is not affected. The nature
of the special monitoring might be situation-specific, and might be the
same as or different than the IMPROVE monitoring protocols. These
proposed changes would reduce the paperwork that states are required to
submit to the EPA on a recurring schedule, since under the proposed
language a state containing one or more Class I areas and participating
in the IMPROVE monitoring program would be relieved of the need to
include information in its SIP regarding monitoring to specifically
assess reasonably attributable visibility impairment absent being
advised to do so. A strategy for monitoring for regional haze
visibility impairment under Sec.  51.308(d)(4) is still required and
any monitoring for reasonably attributable visibility impairment under
Sec.  51.305 would be in addition to that requirement.
    Section 51.306, on long-term strategy requirements for reasonably
attributable visibility impairment, is proposed to be completely
removed and reserved. Like the current version of Sec.  51.302, the
language of this section is outdated. In this case, the EPA believes it
makes sense to delete the entire text of this section and instead refer
to long-term strategy requirements for reasonably attributable
visibility impairment within the text of Sec.  51.308, specifically in
Sec.  51.308(f)(2). In this way, long-term strategy requirements for
reasonably attributable visibility impairment would be retained in
clearer form, and the visibility program would be more understandable
to states and the public by listing the long-term strategy requirements
for both regional haze and reasonably attributable visibility
impairment in one place. Such a change would also reduce the planning
burden on states by making clear in Sec.  51.308(f)(2) that a long-term
strategy for reasonably attributable visibility impairment is not
required without an FLM having made a reasonably attributable
visibility impairment certification under Sec.  51.302(a).
    Several proposed changes in Sec.  51.308 were discussed in Sections
IV.A, B, C, D, E and F of this document. We are also proposing changes
in Sec.  51.308 related to reasonably attributable visibility
impairment. The proposed addition of Sec.  51.308(c) (currently a
reserved section) explains the relationship between regional haze and
reasonably attributable visibility impairment and the state
requirements for each, including that a state would not be required to
address reasonably attributable visibility impairment unless triggered
to do so by an FLM certification under Sec.  51.302(a), and that a
state would not be required to re-address its monitoring strategy for
reasonably attributable visibility impairment unless advised to perform
monitoring as described in the proposed Sec.  51.305.
    The EPA is also proposing changes to the language of Sec.
51.308(f)(2) to describe when reasonably attributable visibility
impairment must be addressed in the long-term strategy required for
regional haze. Finally, proposed changes to Sec.  51.308(f)(6)
regarding the monitoring strategy requirements for SIPs would remove
references to Sec.  51.305 that exist in the corresponding subsection
in Sec.  51.308(d), namely, subsection (4) (again, regarding monitoring
for reasonably attributable visibility impairment).
    Proposed changes to Sec.  51.308(e), BART, relate to a state's
option to enact an emissions trading program or other alternative
measure in lieu of source-specific BART. Under the proposed approach,
if a source is already covered for BART by an approved emissions
trading program or other alternative measure (or the program codified
in Sec.  51.309), certification of that source by an FLM would not
trigger a new BART determination. However, certification would still
trigger the requirement for a reasonable progress analysis. Proposed
changes to Sec.  51.308(e)(4) are similar in nature and motivated by
the same concerns.
    Consistent with our proposal to remove the requirement for states
to periodically assess reasonably attributable visibility impairment,
we are also proposing to amend many sections of 40 CFR part 52, to
remove provisions that establish FIPs that require the EPA to
periodically assess whether reasonably attributable visibility
impairment exists at Class I areas in certain states and to address it
if it does, and to respond to any reasonably attributable visibility
impairment certification that may be directed to a state that does not
have an approved reasonably attributable visibility impairment SIP.
These changes include the removal of Sec. Sec.  52.26 and 52.29, which
now contain the statement of the EPA's obligations, and specific
provisions for 30 states to establish that Sec. Sec.  52.26 and 52.29
are applicable to those states.

H. Consistency Revisions Related to Permitting of New and Modified
Major Sources

    Proposed changes to Sec.  51.307, New Source Review, involve a few
proposed

changes to maintain consistency with other sections of the Regional
Haze Rule and with the CAA. The first change involves Sec.
51.307(b)(1) concerning integral vistas, for which we are proposing
deletion of obsolete language regarding the now-expired identification
period for integral vistas. Instead, the newly proposed addition of a
listing of integral vistas in Sec.  51.304(b) will be referenced. In
section Sec.  51.307(b)(2), the deletion of a reference to specific
sections of the CAA is proposed in order to remove unnecessary
language, as the EPA believes a reference simply to section
``107(d)(1)'' is sufficient.

I. Changes to FLM Consultation Requirements

    The EPA believes that state consultation with FLMs is a critical
part of the creation of quality SIPs. As mentioned earlier, the EPA is
proposing to extend the FLM consultation requirements of Sec.
51.308(i)(2) to progress reports that are not SIP revisions. In
addition, the EPA believes further edits to Sec.  51.308(i)(2) are
necessary because the current requirement for consultation at least 60
days prior to a public hearing may not occur sufficiently early in the
state's planning process to meaningfully inform the state's development
of the long-term strategy. This proposed rule change would add a
requirement that such consultation occur early enough to allow the
state time for full consideration of FLM input, but no fewer than 60
days prior to a public hearing or other public comment opportunity. A
consultation opportunity that takes place no less than 120 days prior
to a public hearing or other public comment opportunity would be deemed
to have been ``early enough.''
    Finally, the EPA notes that pursuant to the existing provisions of
Sec.  51.307(a), the SIP for every state must require the new source
permitting authority to consult with FLMs regarding new source review
of any new major stationary source or major modification that would be
constructed in an area that is designated attainment or unclassified
that may affect visibility in any Class I Federal area. As required by
the regulations, that consultation must include sharing with the FLMs a
copy of all information relevant to the permit application for the
proposed new stationary source or major modification. The regulations
also specify that this material must be provided within particular time
frames. Also, under Sec.  51.307(b)(2), a proposed new major source or
major modification locating in a nonattainment area is subject to
review if it may have an impact on visibility in any mandatory Class I
area. Two EPA guidance documents interpret the consultation
requirement, particularly with regard to evaluating whether a proposed
new major source or major modification may affect visibility in a Class
I area and thus consultation is required.\47\ The EPA regional offices
can provide additional assistance to states in ensuring that their
permitting programs meet the regulations and that the appropriate
consultation is being conducted for affected permits. No changes are
being proposed to these consultation requirements.
---------------------------------------------------------------------------

    \47\ New Source Review Workshop Manual--Prevention of
Significant Deterioration and Nonattainment Area Permitting (Draft),
October 1990, available at: https://www.epa.gov/sites/production/files/2015-07/documents/1990wman.pdf; and Appendix A of Timely
Processing of Prevention of Significant Deterioration (PSD) Permits
when EPA or a PSD-Delegated Air Agency Issues the Permit, October
2012, available at: https://www.epa.gov/sites/production/files/2015-07/documents/timely.pdf.
---------------------------------------------------------------------------

J. Extension of Next Regional Haze SIP Deadline From 2018 to 2021

    The EPA is proposing to amend Sec.  51.308(f) to move the
compliance deadline for the submission of the next periodic
comprehensive SIP revisions from July 31, 2018, to July 31, 2021. Under
this proposal, states would retain the option of submitting their SIP
revisions before July 31, 2021. Regardless of the date on which a state
chooses to submit its periodic comprehensive SIP revision, the EPA
would evaluate that SIP using the same criteria. The EPA is proposing
to leave the end date for the second implementation period at 2028,
regardless of when SIP revisions are submitted. We are proposing this
change as a one-time schedule adjustment. Periodic comprehensive SIP
revisions for the third planning will be due on July 31, 2028, with
future periodic comprehensive SIP revisions due every 10 years
thereafter.
    We are proposing this extension of the due date for periodic
comprehensive SIP revisions to allow states to coordinate regional haze
planning with other regulatory programs, including but not limited to
the Mercury and Air Toxics Standards,\48\ the 2010 1-hour
SO2 NAAQS,\49\ the 2012 annual PM2.5 NAAQS,\50\
and the Clean Power Plan.\51\ With this one-time extension, states
would be able to gather more information on the effects of these
programs and develop periodic comprehensive SIP revisions that are more
integrated with state planning for these other programs, an advantage
that was widely confirmed in our discussions with states. The Regional
Haze Rule requires states to address the impacts of other regulatory
programs when developing their regional haze SIPs. A number of other
regulatory programs will be taking effect in the coming years, which
presents an excellent opportunity for states to coordinate their
strategies to address significant sources of emissions. The EPA expects
this cross-program coordination to lead to better overall policies and
enhanced environmental protection.
---------------------------------------------------------------------------

    \48\ 77 FR 9304, February 16, 2012.
    \49\ 75 FR 35520, June 22, 2010.
    \50\ 78 FR 3086, January 15, 2013.
    \51\ 80 FR 64,662, October 23, 2015. The compliance deadlines in
the Clean Power Plan have been stayed by the Supreme Court. Order in
Pending Case, West Virginia v. EPA, No. 15A773 (Feb. 9, 2016).
---------------------------------------------------------------------------

K. Changes to Scheduling of Regional Haze Progress Reports

    The EPA is proposing to amend the requirements in 40 CFR 51.308(g)
and (h) regarding the timing of submission of reports evaluating
progress towards the natural visibility goal. Under the current rule,
regional haze progress reports are required to be submitted 5 years
after submission of periodic comprehensive SIP revisions. Because
states submitted these first SIP revisions on dates spread across about
a 3-year period, many of the due dates for progress reports currently
do not fall mid-way between the due dates for periodic comprehensive
SIP revisions, as the EPA initially envisioned that they would. Looking
forward, the current Regional Haze Rule would in many cases require a
progress report shortly before or shortly after a periodic
comprehensive SIP revision, at which time it could not be expected to
have much utility as a mid-course review of environmental progress or
much incremental informational value for the public compared to the
data contained in that SIP revision.
    Complementing the proposed amendments to 40 CFR 51.308(f) regarding
the deadlines for submittal of periodic comprehensive revisions, we
propose to amend 40 CFR 51.308 (g) and (h) such that second and
subsequent progress reports would be due by January 31, 2025, July 31,
2033, and every 10 years thereafter, placing one progress report mid-
way between the due dates for periodic comprehensive SIP revisions. The
EPA believes that this timing provides a good balance between allowing
the implementation of the most recent SIP revision to have proceeded
far enough since its adoption for a review to be possible and
worthwhile and having enough time

remaining before the next comprehensive SIP revision for state action
to make changes in its rules or implementation efforts, if necessary,
separately from the actions in that next SIP.
    Regarding the concept of a progress report also being useful at or
near the time of submission of a periodic comprehensive SIP revision,
as the EPA envisioned in the 1999 Regional Haze Rule, we note that
although they are expressed with somewhat different terminology, in
practical terms a progress report would provide little additional
information beyond that required to be addressed in a periodic
comprehensive SIP revision. The only significant additional information
required in a progress report but not explicitly required in a periodic
comprehensive SIP revision is the requirement to report on the trend in
visibility over the whole period since the baseline period of 2000-
2004. While the EPA believes that a state should be aware of, and share
with the public, information on the trend in visibility over the whole
period since the baseline period of 2000-2004, we believe it would be
inefficient to require the preparation of a separate progress report
for this purpose. Therefore, we are proposing to limit the requirement
for separate progress reports to the one due mid-way between periodic
comprehensive SIP revisions, and to add to the requirement for periodic
comprehensive SIP revisions a requirement to include this trend
information. The EPA believes this approach would substantially reduce
administrative burdens and make progress reports of more informational
use to the public, with no attendant reduction in environmental
protection. The EPA solicits comment on this and any alternative
approaches to progress report scheduling.

L. Changes to the Requirement That Regional Haze Progress Reports Be
SIP Revisions

    The EPA is proposing to amend 40 CFR 51.308(g) regarding the
requirements for the form of progress reports. Under the current
regulations, progress reports must take the form of SIP revisions that
comply with the procedural requirements of 40 CFR 51.102, 40 CFR 51.103
and Appendix V to Part 51--Criteria for Determining the Completeness of
Plan Submissions. The EPA included the requirements for progress
reports in the Regional Haze Rule primarily with an emphasis toward
ensuring that the states remain on track during the 10 years between
periodic comprehensive SIP revisions. By requiring progress reports to
be in the form of SIP revisions, the 1999 Regional Haze Rule ensured an
opportunity for public input on the progress reports, while
specifically pointing out that the EPA ``intends for progress reports
to involve significantly less effort than a comprehensive SIP
revision.'' 64 FR 35747 (July 1, 1999). For all SIP revisions, however,
the state must provide public notice and a public hearing if requested,
and it must conform to certain administrative procedural requirements
and provide various administrative material. Also, the submission must
be made by an official who is authorized by state law to submit a SIP
revision. As a required SIP revision, a finding by the EPA that a state
has not submitted a complete progress report by the deadline would
start a ``clock'' for the EPA to prepare, take public comment on, and
issue a progress report like the state was required to submit.
    We are proposing that progress reports need not be in the form of
SIP revisions, but that states must consult with FLMs and obtain public
comment on their progress reports before submission to the EPA. We are
also proposing that the SIP revision that would be due in 2021 must
include a commitment to prepare and submit these progress reports to
the EPA according to the proposed revised schedule (see previous
section). These progress reports would be acknowledged and assessed by
the EPA, but our review of these reports would not result in a formal
approval or disapproval of them.
    The EPA is proposing these changes because it believes these
reports are not the kind of state submissions for which the formality
of a SIP revision, and the accompanying requirement for the EPA to have
to prepare the report within 2 years of finding that a state has failed
to do so, are warranted. It is important to note that as part of the
EPA's review of the report, we will follow up with the state on any
appropriate next steps. There are also additional remedies, such as
undertaking a less formal assessment of the results of the
implementation of the previously submitted SIP, that are available to
the EPA in the event a state fails to properly submit a progress
report. These changes have been widely supported by state air agencies
in our pre-proposal consultations because they would allow more
efficient use of state resources. This option would relieve states of
the obligation to follow the procedural requirements of 40 CFR 51.102
and 51.103. States have expressed concern that these procedural
requirements are resource-intensive, and increase the burden on states
by requiring formal procedures be followed when submitting progress
reports. By avoiding the specific formal steps required for a SIP
revision, including requirements imposed by state law that may involve
time-consuming steps beyond those required by the EPA, this proposal
may also reduce the time between the completion of the technical
analysis in the progress report and when the final report becomes
available to the EPA and the public. Thus, progress reports could
contain fresher information on the environmental progress being made by
a state. Removing the requirement that progress reports be submitted as
SIP revisions is consistent with regulatory requirements for similar
reports from states for progress reporting or planning purposes where
control requirements are not imposed, such as annual monitoring plans
required for planning and maintenance of state monitoring networks.\52\
---------------------------------------------------------------------------

    \52\ See 40 CFR 58.10(a)(1) and (2).
---------------------------------------------------------------------------

    The EPA invites comment on whether it should finalize this proposed
change. Also, the EPA invites comment on changing the progress report
scheduling as described in the previous section without making any
change to the requirement that progress reports take the form of SIP
revisions, and vice versa.
    It is important to note that under this option, states would still
be required to include the required progress report elements listed in
40 CFR 51.308(g)(1) through (g)(6). Also, Sec.  51.308(h) would
continue to require that at the same time the state is required to
submit a progress report, it must also take one of four listed actions
concerning whether the SIP is adequate to achieve established goals for
visibility improvement. Where a state determines that its own SIP is or
may be inadequate to ensure reasonable progress due to emissions from
sources within the state, the state will continue to have an obligation
to revise its SIP to address the plan's deficiencies within 1 year of
its submission of such a determination.
    Upon receipt of such progress reports, the EPA would review the
reports. In addition, the EPA intends to create a system of logging
progress reports as they are received, and making them available to the
public. In addition to putting the public on notice that a progress
report was received by the EPA, this system would provide the public an
opportunity to view the contents of the progress report. Although the
EPA would not formally approve or disapprove a progress report,

the EPA would still have discretion to assess the adequacy of the SIP,
relying in part on the information in the progress report. Under the
CAA, a discretionary determination that the SIP is inadequate would
create a non-discretionary duty for the EPA to issue a SIP call
requiring the state to correct the inadequacy. A failure by the state
to submit a progress report could be determined by the EPA to
constitute failure to implement the regional haze SIP, given that we
are proposing that every regional haze SIP include a commitment to
submit the required progress reports (see next paragraph).
    We are proposing that the next periodic comprehensive SIP revisions
(currently due in 2018 but proposed to be due in 2021) would need to
include a commitment for states to provide progress reports. The 1999
Regional Haze Rule does not require such a commitment because the
current requirement for progress reports to be submitted in the form of
SIP revisions makes such a commitment superfluous. The EPA solicits
comment on this or alternative approaches to ensuring that states
continue to provide progress reports.

M. Changes to Requirements Related to the Grand Canyon Visibility
Transport Commission

    Section 51.309 has limited applicability going forward because its
provisions apply only to 16 Class I areas covered by the Grand Canyon
Visibility Transport Commission Report, and only to the first regional
haze implementation period (i.e., through 2018). Nevertheless, certain
conforming amendments at this time are appropriate to avoid confusion
going forward. Section 51.309(d)(4)(v) is proposed to be amended to
correctly refer to the new Sec.  51.302(b) (in lieu of (e), which no
longer exists in the proposed section Sec.  51.302) and to delete the
reference to BART since it does not appear in Sec.  51.302(b). The
title of Sec.  51.309(c)(10), Periodic implementation plan revisions,
is proposed to be amended to include ``and progress reports'' at the
end. This insertion would complement the proposed amendments that will
no longer require progress reports be considered SIP revisions by
making clear from the title of the section that it applies to both SIP
revisions and progress reports. Within Sec.  51.309(c)(10), amendments
are proposed that would preserve the existing requirement that the
progress reports due in 2013 were to take the form of SIP revisions,
but direct the reader to the provisions of Sec.  51.308(g) for
subsequent progress reports. In similar fashion, Sec.  51.309(c)(10)(i)
and (ii) would be amended to specifically refer to the 2013 progress
reports, while Sec.  51.309(c)(10)(iii) would point to Sec.  51.308(g)
for subsequent progress reports. Section 51.309(c)(10)(iv) is proposed
to be added to indicate that subsequent progress reports are subject to
the requirements of Sec.  51.308(h) regarding determinations of
adequacy of existing SIPs.
    A final change in section 51.309 appears in Sec.
51.309(g)(2)(iii). This change is purely to correct a typographical
error and the EPA will therefore not consider comments on this
subsection.

V. Environmental Justice Considerations

    The EPA believes this action would not have disproportionately high
and adverse human health, well-being or environmental effects on
minority, low-income or indigenous populations because it would not
negatively affect the level of protection provided to human health,
well-being or the environment under the CAA's visibility protection
program. When promulgated, these proposed regulations will revise
procedural and timing aspects of the SIP requirements for visibility
protection but will not substantively change the requirement that SIPs
provide for reasonable progress towards the goal of natural visibility
conditions. These SIP requirements are designed to protect all segments
of the general population.
    The EPA acknowledges that the proposed delay in submitting SIP
revisions from 2018 to 2021 might cause delays in when sources must
comply with any new requirements. However, because neither the CAA nor
the existing Regional Haze Rule set specific deadlines for when sources
must comply with any new requirements in a state's next periodic
comprehensive SIP revision, states have substantial discretion in
establishing reasonable compliance deadlines for measures in their
SIPs. Given this, we expect to see a range of compliance deadlines in
the next round of regional haze SIPs from early in the second
implementation period to 2028, depending on the types of measures
adopted, whether or not these proposed rule changes are finalized.
Thus, the EPA believes the delay in the periodic comprehensive SIP
revision submission deadline from 2018 to 2021 will not meaningfully
reduce the overall progress towards better visibility made by the end
of 2028 and will not meaningfully adversely affect environmental
protection for all general segments of the population.

VI. Statutory and Executive Order Reviews

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

    This action is a significant regulatory action that was submitted
to the OMB for review because it raises novel policy issues. Any
changes made in response to OMB recommendations have been documented in
the docket.

B. Paperwork Reduction Act (PRA)

    The information collection activities in this proposed rule have
been submitted for approval to the OMB under the PRA. The ICR document
that the EPA prepared has been assigned the EPA ICR number 2540.01. OMB
has previously approved the information collection activities contained
in the existing regulations and has assigned OMB control number 2060-
0421. You can find a copy of the ICR in the docket for this rule, and
it is briefly summarized here.
    The EPA is proposing these amendments to requirements for state
regional haze planning to change the requirements that must be met by
states in developing regional haze SIPs, periodic comprehensive SIP
revisions, and progress reports for regional haze. The main intended
effects of this rulemaking are to provide states with additional time
to submit regional haze plans for the second implementation period and
to provide states with an improved schedule and process for progress
report submission. Further reductions in burden on states include this
proposal's removal of the requirement for progress reports to be SIP
revisions, clarifying that states are not required to project emissions
inventories as part of preparing a progress report, and relieving the
state of the need to review its visibility monitoring strategy within
the context of the progress report. With all of these proposed changes
considered, the overall burden on states would represent a reduction
compared to what would otherwise occur if the provisions of the current
rule were to stay in place. Total estimated burden is estimated to be
reduced from 10,307 hours (per year) to 5,974 hours (per year), and
total estimated cost is expected to be reduced from $510,498 (per year)
to $295,876 (per year). All states are required to submit regional haze
SIPs and progress reports under this rule.
    Respondents/affected entities: All state air agencies.
    Respondent's obligation to respond: Mandatory, in accordance with
the

provisions of the 1999 Regional Haze Rule.
    Estimated number of respondents: 52: 50 states, District of
Columbia and U.S. Virgin Islands.
    Frequency of response: Approximately every 10 years (SIP) and
approximately every 10 years (progress report).
    Total estimated burden: 5,974 hours (per year). Burden is defined
at 5 CFR 1320.3(b).
    Total estimated cost: $295,876 (per year), includes $0 annualized
capital or operation & maintenance costs.
    An agency may not conduct or sponsor, and a person is not required
to respond to, a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for the
EPA's regulations in 40 CFR are listed in 40 CFR part 9.
    Submit your comments on the agency's need for this information, the
accuracy of the provided burden estimates and any suggested methods for
minimizing respondent burden to the EPA using the docket identified at
the beginning of this rule. You may also send your ICR-related comments
to OMB's Office of Information and Regulatory Affairs via email to
<EMAIL_ADDRESS>Attention: Desk Officer for the EPA.
Since OMB is required to make a decision concerning the ICR between 30
and 60 days after receipt, OMB must receive comments no later than June
3, 2016. The EPA will respond to any ICR-related comments in the final
rule.

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic
impact on a substantial number of small entities under the RFA. This
action will not impose any requirements on small entities. Entities
potentially affected directly by this proposal include state
governments, and for the purposes of the RFA, state governments are not
considered small government. Tribes may choose to follow the provisions
of the Regional Haze Rule but are not required to do so. Other types of
small entities are not directly subject to the requirements of this
rule. The EPA continues to be interested in the potential impacts of
the proposed rule on small entities and welcomes comments on issues
related to such impacts.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain any unfunded mandate as described in
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect
small governments. This action imposes no enforceable duty on any
state, local or tribal governments or the private sector. The CAA
imposes the obligation for states to submit regional haze SIPs. In this
rule, the EPA is proposing to revise those requirements in a manner
that would not increase the obligation of any state, local or tribal
governments or the private sector. In this rule, the EPA is also
proposing to extend the reasonably attributable visibility impairment
certification provisions to some additional states, but these states
are not small governments and any mandate on the private sector would
be indirect since this rule does not mandate how an affected state
should address such a certification. Therefore, this action is not
subject to the requirements of sections 202, 203 and 205 of the UMRA.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have
substantial direct effects on the states, on the relationship between
the national government and the states, or on the distribution of power
and responsibilities among the various levels of government. The
requirement to submit regional haze SIPs is mandated by the CAA. Thus,
Executive Order 13132 does not apply to these proposed regulations.
    In the spirit of Executive Order 13132 and consistent with the EPA
policy to promote communications between the EPA and state and local
governments, the EPA has already consulted extensively with state air
agency officials prior to this proposal. The EPA specifically solicits
comments on this proposed action from state and local officials. In
addition, the EPA intends to meet with organizations representing state
and local officials during the comment period for this action.

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

    This proposed action does not have tribal implications as specified
in Executive Order 13175. It would not have a substantial direct effect
on one or more Indian tribes. Furthermore, these proposed regulation
revisions do not affect the relationship or distribution of power and
responsibilities between the federal government and Indian tribes. The
CAA and the TAR establish the relationship of the federal government
and tribes in characterizing air quality and developing plans to
protect visibility in Class I areas. Thus, Executive Order 13175 does
not apply to this action.
    Although Executive Order 13175 does not apply to this action, the
EPA solicits comment on this proposed action from tribal officials. The
EPA also intends to offer to consult with any tribal government to
discuss this proposal. See also Section III.B.5 of this document for
further discussion regarding the role of tribes in visibility
protection.

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

    The EPA interprets Executive Order 13045 as applying only to those
regulatory actions that concern environmental health or safety risks
that the EPA has reason to believe may disproportionately affect
children, per the definition of ``covered regulatory action'' in
section 2-202 of the Executive Order. This action is not subject to
Executive Order 13045 because it does not concern an environmental
health risk or safety risk.

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

    This action is not a ``significant energy action'' because it is
not likely to have a significant adverse effect on the supply,
distribution or use of energy.

I. National Technology Transfer and Advancement Act

    This rulemaking does not involve technical standards.

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

    The EPA believes the human health or environmental risk addressed
by this action will not have disproportionately high and adverse human
health or environmental effects on minority, low-income or indigenous
populations. The results of our evaluation are contained in Section V
of this document.

VII. Statutory Authority

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

List of Subjects

40 CFR Part 51

    Environmental protection, Administrative practice and procedure,
Air pollution control, Nitrogen dioxide, Particulate matter, Sulfur
oxides, Transportation, Volatile organic compounds.

40 CFR Part 52

    Environmental protection, Administrative practice and procedure,
Air pollution control, Incorporation by reference, Nitrogen dioxide,
Particulate matter, Sulfur oxides, Transportation, Volatile organic
compounds.

    Dated: April 25, 2016.
Gina McCarthy,
Administrator.

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

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

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

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

0
2. In Sec.  51.300, revise paragraph (b) to read as follows:

Sec.  51.300  Purpose and applicability.

* * * * *
    (b) Applicability--The provisions of this subpart are applicable to
all States as defined in section 302(d) of the Clean Air Act (CAA)
except Guam, Puerto Rico, American Samoa, and the Northern Mariana
Islands.
* * * * *
0
3. In Sec.  51.301:
0
a. Add a definition for ``Clearest days;''
0
b. Revise the definition of ``Deciview;''
0
c. Add definitions for ``Deciview index'' and ``End of the applicable
implementation period;''
0
d. Revise the definitions of ``Federal Class I area,'' ``Least impaired
days,'' ``Mandatory Class I Federal Area,'' and ``Most impaired days;''
0
e. Add definitions for '' ``Natural visibility conditions'' and
``Prescribed fire;''
0
f. Revise the definition of ``Reasonably attributable;''
0
g. Add a definition for ``Visibility;''
0
h. Revise the definitions of ``Visibility impairment;'' and
0
i. Add definitions for ``Wildfire,'' and ``Wildland.''
    The revisions and additions read as follows:

Sec.  51.301  Definitions.

* * * * *
    Clearest days means the twenty percent of monitored days in a
calendar year with the lowest values of the deciview index.
    Deciview is the unit of measurement on the deciview index scale for
quantifying in a standard manner human perceptions of visibility.
    Deciview index means a value for a day that is derived from
calculated or measured light extinction, such that uniform increments
of the index correspond to uniform incremental changes in perception
across the entire range of conditions, from pristine to very obscured.
The deciview index is calculated based on the following equation (for
the purposes of calculating deciview using IMPROVE data, the
atmospheric light extinction coefficient must be calculated from
aerosol measurements and an estimate of Rayleigh scattering):
    Deciview index=10 ln (bext/10 Mm-1).
    bext=the atmospheric light extinction coefficient,
expressed in inverse megameters (Mm-1).
    End of the applicable implementation period means December 31 of
the year in which the next periodic comprehensive implementation plan
revision is due under Sec.  51.308(f).
* * * * *
    Federal Class I area or Class I Federal area means any Federal land
that is classified or reclassified Class I. Mandatory Federal Class I
areas are identified in part 81, subpart D. Other Federal Class I areas
are identified in part 52 of this title.
* * * * *
    Least impaired days means the twenty percent of monitored days in a
calendar year with the lowest amounts of visibility impairment.
* * * * *
    Mandatory Class I Federal Area or Mandatory Federal Class I Area
means any area identified in part 81, subpart D of this title.
    Most impaired days means the twenty percent of monitored days in a
calendar year with the highest amounts of visibility impairment.
* * * * *
    Natural visibility conditions means visibility (contrast,
coloration, and texture) that would have existed under natural
conditions. Natural visibility conditions vary with time and location,
and are estimated or inferred rather than directly measured.
* * * * *
    Prescribed fire means any fire intentionally ignited by management
actions in accordance with applicable laws, policies, and regulations
to meet specific land or resource management objectives.
* * * * *
    Reasonably attributable means attributable by visual observation or
any other appropriate technique.
* * * * *
    Visibility means the degree of perceived clarity when viewing
objects at a distance. Visibility includes perceived changes in
contrast, coloration, and texture of elements in a scene.
    Visibility impairment means any humanly perceptible difference
between actual visibility conditions and natural visibility conditions.
Because natural visibility conditions can only be estimated or
inferred, visibility impairment also is estimated or inferred rather
than directly measured.
* * * * *
    Wildfire means any fire started by an unplanned ignition caused by
lightning; volcanoes; other acts of nature; unauthorized activity; or
accidental, human-caused actions, or a prescribed fire that has been
declared to be a wildfire. A wildfire that predominantly occurs on
wildland is a natural event.
    Wildland means an area in which human activity and development is
essentially non-existent, except for roads, railroads, power lines, and
similar transportation facilities. Structures, if any, are widely
scattered.
* * * * *
0
4. Revise Sec.  51.302, to read as follows:

Sec.  51.302  Reasonably attributable visibility impairment.

    (a) The affected Federal Land Manager may certify, at any time,
that there exists reasonably attributable impairment of visibility in
any mandatory Class I Federal area and identify which single source or
small number of sources is responsible for such impairment. The
affected Federal Land Manager will provide the certification to the
State in which the impairment occurs and the State(s) in which the
source(s) is located.
    (b) The State(s) in which the source(s) is located shall revise its
regional haze implementation plan, in accordance with the schedules set
forth in paragraphs (d)(1) and (2) of this section, to include for each
source or small number of sources that the Federal Land Manager has
identified in whole or in part for reasonably attributable visibility
impairment as part of a certification under paragraph (a) of this
section:
    (1) A determination, based on the factors set forth in Sec.
51.308(d)(1)(i)(A), of the control measures, if any, that are necessary
with respect to the source or sources in order for the plan to make
reasonable progress toward natural visibility conditions in the
affected Class I Federal area;

    (2) Emission limitations that reflect the degree of emission
reduction achievable by such control measures and schedules for
compliance as expeditiously as practicable; and
    (3) Monitoring, recordkeeping, and reporting requirements
sufficient to ensure the enforceability of the emission limitations.
    (c) If a source that the Federal Land Manager has identified as
responsible in whole or in part for reasonably attributable visibility
impairment as part of a certification under paragraph (a) of this
section is a BART-eligible source, and if there is not in effect as of
the date of the certification a fully or conditionally approved
implementation plan addressing the BART requirement for that source
(which existing plan may incorporate either source-specific emission
limitations reflecting the emission control performance of BART, an
alternative program to address the BART requirement under Sec.
51.308(e)(2), (3), and (4), or for sources of SO2 a program
approved under paragraph Sec.  51.309(d)(4)), then the State shall
revise its regional haze implementation plan to meet the requirements
of Sec.  51.308(e) with respect to that source, taking into account
current conditions related to the factors listed in Sec.
51.308(e)(1)(ii)(A). This requirement is in addition to the requirement
of paragraph (b) of this section.

Proposed Paragraph (d): Option One

    (d) For any existing reasonably attributable visibility impairment
the Federal Land Manager certifies to the State(s) under paragraph (a)
of this section, the State(s) shall submit a revision to its regional
haze implementation plan that includes the elements described in
paragraph (b) and
    (c) no later than 3 years after the date of the certification. The
State(s) is not required at that time to also revise its reasonable
progress goals to reflect the additional emission reductions required
from the source or sources.]

Proposed Paragraph (d): Option Two

    (d) For any existing reasonably attributable visibility impairment
the Federal Land Manager certifies to the State(s) under paragraph (a)
of this section more than 2 years prior to the due date for a regional
haze implementation plan revision required under Sec.  51.308(f) or the
due date for a regional haze progress report required under Sec.
51.308(g), the State(s) shall include the elements described in
paragraphs (b) and (c) in a plan revision by the due date for that
implementation plan revision as part of such revision or by the due
date for the progress report, whichever is due first, provided that the
earlier date is at least 2 years after the certification. For plan
revisions submitted by the due date for the progress report, the
State(s) is not required at that time to also revise its reasonable
progress goals to reflect the additional emission reductions required
from the source or sources.]

Proposed Paragraph (d): Option Three

    (d)(1) For any existing reasonably attributable visibility
impairment the Federal Land Manager certifies to the State(s) under
paragraph (a) of this section more than 2 years prior to the due date
for a regional haze implementation plan revision required under Sec.
51.308(f), the State(s) shall include the elements described in
paragraphs (b) and (c) in such revision and such elements shall be
considered a required part of such revision.
    (2) For any existing reasonably attributable visibility impairment
the Federal Land Manager certifies to the State(s) under paragraph (a)
of this section less than 2 years prior to the due date for a regional
haze implementation plan revision required under Sec.  51.308(f), but
no more than 6 months subsequent to the submission date of that
implementation plan revision or no more than 6 months subsequent to a
further plan revision that changes the emission limitation for the
subject source, the State(s) shall submit a revision to its regional
haze implementation plan that includes the elements described in
paragraph (b) and (c) no later than 2 years after the date of the
certification. The State(s) is not required at that time to also revise
its reasonable progress goals to reflect the additional emission
reductions required from the source or sources.]

0
5. Revise Sec.  51.304 to read as follows:

Sec.  51.304  Identification of integral vistas.

    (a) Federal Land Managers were required to identify any integral
vistas on or before December 31, 1985, according to criteria the
Federal Land Managers developed. These criteria must have included, but
were not limited to, whether the integral vista was important to the
visitor's visual experience of the mandatory Class I Federal area.
    (b) The following integral vistas were identified by Federal Land
Managers: at Roosevelt Campobello International Park, from the
observation point of Roosevelt cottage and beach area, the viewing
angle from 244 to 256 degrees; and at Roosevelt Campobello
International Park, from the observation point of Friar's Head, the
viewing angle from 154 to 194 degrees.
    (c) The State must list in its implementation plan any integral
vista listed in paragraph (b) of this section.
    (d) [Reserved]
0
6. Section 51.305 is revised to read as follows:

Sec.  51.305  Monitoring for reasonably attributable visibility
impairment.

    For the purposes of addressing reasonably attributable visibility
impairment, if the Administrator, Regional Administrator, or the
affected Federal Land Manager has advised a State containing a
mandatory Class I Federal area of a need for monitoring to assess
reasonably attributable visibility impairment at a mandatory Class I
Federal area in addition to the monitoring currently being conducted to
meet the requirements of Sec.  51.308(d)(4), the State must include in
the next implementation plan revision to meet the requirement of Sec.
51.308(f) an appropriate strategy for evaluating reasonably
attributable visibility impairment in the mandatory Class I Federal
area by visual observation or other appropriate monitoring techniques.
Such strategy must take into account current and anticipated visibility
monitoring research, the availability of appropriate monitoring
techniques, and such guidance as is provided by the Agency.

Sec.  51.306  [Removed and Reserved]

0
7. Section 51.306 is removed and reserved.
0
8. In Sec.  51.307, revise paragraphs (a) introductory text and (b)(1)
and (2) to read as follows:

Sec.  51.307  New source review.

    (a) For purposes of new source review of any new major stationary
source or major modification that would be constructed in an area that
is designated attainment or unclassified under section 107(d) of the
CAA, the State plan must, in any review under Sec.  51.166 with respect
to visibility protection and analyses, provide for:
* * * * *
    (b) * * *
    (1) That may have an impact on any integral vista of a mandatory
Class I Federal area listed in Sec.  51.304(b), or
    (2) That proposes to locate in an area classified as nonattainment
under section 107(d)(1) of the Clean Air Act that may have an impact on
visibility in any mandatory Class I Federal area.
* * * * *
0
9. In Sec.  51.308:
0
a. Revise paragraph (b);
0
b. Add paragraph (c);
0
c. Revise paragraphs (d)(2)(iv), (d)(3), (e)(2)(v), (e)(4) and (5), and
(f);

0
d. Revise paragraphs (g) introductory text, (g)(3) through (7), (h)
introductory text, (h)(1), (i)(2) introductory text, and (i)(3) and
(4).
    The revisions and additions read as follows:

Sec.  51.308  Regional haze program requirements.

* * * * *
    (b) When are the first implementation plans due under the regional
haze program? Except as provided in Sec.  51.309(c), each State
identified in Sec.  51.300(b) must submit, for the entire State, an
implementation plan for regional haze meeting the requirements of
paragraphs (d) and (e) of this section no later than December 17, 2007.
    (c) What is the relationship between requirements for regional haze
and requirements for reasonably attributable visibility impairment? A
State must address any reasonably attributable visibility impairment
certified by a Federal Land Manager under Sec.  51.302(a) in its
regional haze implementation plan, as required by Sec.  51.302(b)-(d).
A State must also meet the requirements of Sec.  51.305 if the
Administrator, Regional Administrator, or the Federal Land Manager has
advised a State under Sec.  51.305 of a need for additional monitoring
to assess reasonably attributable visibility impairment at a mandatory
Class I Federal area.
    (d) * * *
    (2) * * *
    (iv) For the first implementation plan addressing the requirements
of paragraphs (d) and (e) of this section, the number of deciviews by
which baseline conditions exceed natural visibility conditions for the
most impaired and least impaired days.
    (3) Long-term strategy for regional haze. Each State listed in
Sec.  51.300(b) must submit a long-term strategy that addresses
regional haze visibility impairment for each mandatory Class I Federal
area within the State and for each mandatory Class I Federal area
located outside the State that may be affected by emissions from the
State. The long-term strategy must include enforceable emissions
limitations, compliance schedules, and other measures as necessary to
achieve the reasonable progress goals established by States having
mandatory Class I Federal areas. In establishing its long-term strategy
for regional haze, the State must meet the following requirements:
* * * * *
    (e) * * *
    (2) * * *
    (v) At the State's option, a provision that the emissions trading
program or other alternative measure may include a geographic
enhancement to the program to address the requirement under Sec.
51.302(b) related to reasonably attributable impairment from the
pollutants covered under the emissions trading program or other
alternative measure.
* * * * *
    (4) A State subject to a trading program established in accordance
with Sec.  52.38 or Sec.  52.39 under a Transport Rule Federal
Implementation Plan need not require BART-eligible fossil fuel-fired
steam electric plants in the State to install, operate, and maintain
BART for the pollutant covered by such trading program in the State. A
State that chooses to meet the emission reduction requirements of the
Transport Rule by submitting a SIP revision that establishes a trading
program and is approved as meeting the requirements of Sec.  52.38 or
Sec.  52.39 also need not require BART-eligible fossil fuel-fired steam
electric plants in the State to install, operate, and maintain BART for
the pollutant covered by such trading program in the State. A State may
adopt provisions, consistent with the requirements applicable to the
State for a trading program established in accordance with Sec.  52.38
or Sec.  52.39 under the Transport Rule Federal Implementation Plan or
established under a SIP revision that is approved as meeting the
requirements of Sec.  52.38 or Sec.  52.39, for a geographic
enhancement to the program to address any requirement under Sec.
51.302(b) related to reasonably attributable impairment from the
pollutant covered by such trading program in that State.
    (5) After a State has met the requirements for BART or implemented
emissions trading program or other alternative measure that achieves
more reasonable progress than the installation and operation of BART,
BART-eligible sources will be subject to the requirements of paragraphs
(d) and (f) of this section, as applicable, in the same manner as other
sources.
* * * * *
    (f) Requirements for periodic comprehensive revisions of
implementation plans for regional haze. Each State identified in Sec.
51.300(b) must revise and submit its regional haze implementation plan
revision to EPA by July 31, 2021, July 31, 2028, and every 10 years
thereafter. The plan revision due on or before July 31, 2021 must
include a commitment by the State to meet the requirements of paragraph
(g). In each plan revision, the State must address regional haze in
each mandatory Class I Federal area located within the State and in
each mandatory Class I Federal area located outside the State that may
be affected by emissions from within the State. To meet the core
requirements for regional haze for these areas, the State must submit
an implementation plan containing the following plan elements and
supporting documentation for all required analyses:
    (1) Calculations of baseline, current, and natural visibility
conditions; progress to date; and the uniform rate of progress. For
each mandatory Class I Federal area located within the State, the State
must determine the following:
    (i) Baseline visibility conditions for the most impaired and
clearest days. The period for establishing baseline visibility
conditions is 2000 to 2004. For purposes of calculating and displaying
the uniform rate of progress, baseline visibility conditions must be
associated with the last day of this period. Baseline visibility
conditions must be calculated, using available monitoring data, by
establishing the average deciview index for the most impaired and
clearest days for each calendar year from 2000 to 2004. The baseline
visibility conditions are the average of these annual values. For
mandatory Class I Federal areas without onsite monitoring data for
2000-2004, the State must establish baseline values using the most
representative available monitoring data for 2000-2004, in consultation
with the Administrator or his or her designee. For mandatory Class I
Federal areas with incomplete data availability for 2000-2004, the
State must establish baseline values using the closest 5 complete years
of monitoring data.
    (ii) Natural visibility conditions for the most impaired and
clearest days. Natural visibility conditions must be calculated by
estimating the deciview index existing under natural conditions for the
most impaired and clearest days, based on available monitoring
information and appropriate data analysis techniques; and
    (iii) Current visibility conditions for the most impaired and
clearest days. The period for calculating current visibility conditions
is the most recent 5-year period for which data are available. Current
visibility conditions must be calculated based on the annual average
level of visibility impairment for the most impaired and clearest days
for each of these 5 years. Current visibility conditions are the
average of these annual values.
    (iv) Progress to date for the most impaired and clearest days.
Actual progress made towards natural conditions since the baseline
period, and actual progress made during the previous implementation
period up to and including to the period for

calculating current visibility conditions, for the most impaired and
clearest days, must be calculated.
    (v) Difference between current visibility conditions and natural
visibility conditions. The number of deciviews by which current
visibility conditions exceed natural visibility conditions, for the
most impaired and clearest days, must be calculated.
    (vi) Uniform rate of progress. (A) The uniform rate of progress for
each mandatory Class I Federal area in the State must be calculated. To
calculate this uniform rate of progress, the State must compare
baseline visibility conditions to natural visibility conditions in the
mandatory Class I Federal area and determine the uniform rate of
visibility improvement (measured in deciviews of improvement per year)
that would need to be maintained during each implementation period in
order to attain natural visibility conditions by the end of 2064.
    (B) The State may submit a request to the Administrator seeking an
adjustment to the uniform rate of progress for a mandatory Class I
Federal area to account for impacts from (1) anthropogenic sources
outside the United States and/or (2) wildland prescribed fires that
were conducted with the objective to establish, restore, and/or
maintain sustainable and resilient wildland ecosystems, to reduce the
risk of catastrophic wildfires, and/or to preserve endangered or
threatened species during which appropriate basic smoke management
practices were applied. To calculate the proposed adjustment, the State
must add the estimated impacts to natural visibility conditions and
compare the resulting value to baseline visibility conditions. If the
Administrator determines that the State has estimated the impacts from
anthropogenic sources outside the United States or wildland prescribed
fires using scientifically valid data and methods, the Administrator
may approve the proposed adjustment to the uniform rate of progress for
use in the State's implementation plan.
    (2) Long-term strategy for regional haze and reasonably
attributable visibility impairment. Each State must submit a long-term
strategy that addresses regional haze visibility impairment, and if
necessary any reasonably attributable visibility impairment certified
by the Federal Land Manager under Sec.  51.302(a), for each mandatory
Class I Federal area within the State and for each mandatory Class I
Federal area located outside the State that may be affected by
emissions from the State. The long-term strategy must include the
enforceable emissions limitations, compliance schedules, and other
measures that are necessary to achieve reasonable progress, as
determined pursuant to (f)(2)(i) through (vi). In establishing its
long-term strategy for regional haze, the State must meet the following
requirements:
    (i) The State must consider and analyze emission reduction measures
based on the costs of compliance, the time necessary for compliance,
the energy and non-air quality environmental impacts of compliance, and
the remaining useful life of any potentially affected major or minor
stationary source or group of sources. The State must document the
criteria used to determine which sources or groups of sources were
evaluated, and how these four factors were taken into consideration in
selecting the measures for inclusion in its long-term strategy.
    (ii) The State must consider the uniform rate of improvement in
visibility, the emission reduction measures identified in (f)(2)(i),
and additional measures being adopted by other contributing states in
(f)(2)(iii) as needed to make reasonable progress towards natural
visibility conditions for the period covered by the implementation
plan.
    (iii) The State must consult with those States which may reasonably
be anticipated to cause or contribute to visibility impairment in the
mandatory Class I Federal area.
    (A) Contributing States. Where the State has emissions that are
reasonably anticipated to contribute to visibility impairment in any
mandatory Class I Federal area located in another State or States, the
State must consult with the other State(s) in order to develop
coordinated emission management strategies. The State must demonstrate
that it has included in its implementation plan all measures necessary
to obtain its share of the emission reductions needed to provide for
reasonable progress towards natural visibility conditions in the
mandatory Class I Federal area located in the other State or States. If
the State has participated in a regional planning process, the State
must also ensure that it has included all measures needed to achieve
its apportionment of emission reduction obligations agreed upon through
that process.
    (B) States affected by contributing States. A State with a
mandatory Class I Federal area must consult with any other State having
emissions that are reasonably anticipated to contribute to visibility
impairment in that area regarding the emission reductions needed in
each State to provide for reasonable progress towards natural
visibility conditions in that area. If the State has participated in a
regional planning process, the State must ensure it has included all
measures needed to achieve its apportionment of emission reduction
obligations agreed upon through that process.
    (C) In any situation in which a State cannot agree with another
State or group of States on the emission reductions needed for
reasonable progress towards natural visibility conditions in any
mandatory Class I Federal area, each involved State must describe in
its submittal the actions taken to resolve the disagreement. In
reviewing the State's implementation plan submittal, the Administrator
will take this information into account in determining whether the
State's implementation plan provides for reasonable progress towards
natural visibility conditions at each mandatory Class I Federal area
that is located in the State or that may be affected by emissions from
the State. All substantive interstate consultations must be documented.
    (iv) As part of the demonstration required by (f)(2)(i), the State
must document the technical basis, including information on the factors
listed in (f)(2)(i) and modeling, monitoring, and emissions
information, on which the State is relying to determine the emission
reductions from anthropogenic sources in the State that are necessary
for achieving reasonable progress towards natural visibility conditions
in each mandatory Class I Federal area it affects. The State may meet
this requirement by relying on technical analyses developed by a
regional planning process and approved by all State participants. The
State must identify the baseline emissions inventory on which its
strategies are based. The baseline emissions inventory year shall be
the most recent year for which the State has submitted emission
inventory information to the Administrator in compliance with the
triennial reporting requirements of subpart A of this part unless the
State adequately justifies the use of another inventory year.
    (v) The State must identify all anthropogenic sources of visibility
impairment considered by the State in developing its long-term strategy
and the criteria used to select the sources considered. The State
should consider major and minor stationary sources, mobile sources, and
area sources.
    (vi) The State must consider, at a minimum, the following factors
in developing its long-term strategy:
    (A) Emission reductions due to ongoing air pollution control
programs, including measures to address

reasonably attributable visibility impairment;
    (B) Measures to mitigate the impacts of construction activities;
    (C) Emissions limitations and schedules for compliance to achieve
the reasonable progress goal;
    (D) Source retirement and replacement schedules;
    (E) Basic smoke management practices for prescribed fire used for
agricultural and wildland vegetation management purposes and smoke
management programs as currently exist within the State for these
purposes;
    (F) Enforceability of emissions limitations and control measures;
and
    (G) The anticipated net effect on visibility due to projected
changes in point, area, and mobile source emissions over the period
addressed by the long-term strategy.
    (3) Reasonable progress goals. (i) A state in which a mandatory
Class I Federal area is located must establish reasonable progress
goals (expressed in deciviews) that reflect the visibility conditions
that are projected to be achieved by the end of the applicable
implementation period as a result of all enforceable emissions
limitations, compliance schedules, and other measures required under
paragraph (f)(2) and the implementation of other requirements of the
CAA. The long-term strategy and the reasonable progress goals must
provide for an improvement in visibility for the most impaired days and
ensure no degradation in visibility for the clearest days since the
baseline period.
    (ii)(A) If a State in which a mandatory Class I Federal area is
located establishes a reasonable progress goal for the most impaired
days that provides for a slower rate of improvement in visibility than
the uniform rate of progress calculated under paragraph (f)(1)(vi) of
this section, the State must demonstrate, based on the analysis
required by paragraph (f)(2)(i) of this section, that there are no
additional emission reduction measures for anthropogenic sources or
groups of sources in the State that may reasonably be anticipated to
contribute to visibility impairment in the Class I area that would be
reasonable to include in the long-term strategy. The State must provide
a robust demonstration, including documenting the criteria used to
determine which sources or groups of sources were evaluated and how the
four factors required by paragraph (f)(2)(i) were taken into
consideration in selecting the measures for inclusion in its long-term
strategy. The State must provide to the public for review as part of
its implementation plan an assessment of the number of years it would
take to attain natural visibility conditions if visibility improvement
were to continue at the rate of progress selected by the State as
reasonable for the implementation period.
    (B) If a State contains sources which are reasonably anticipated to
contribute to visibility impairment in a mandatory Class I Federal area
in another State for which a demonstration by the other State is
required under (f)(3)(ii)(A), the State must demonstrate that there are
no additional emission reduction measures for anthropogenic sources or
groups of sources in the State that may reasonably be anticipated to
contribute to visibility impairment in the Class I area that would be
reasonable to include in its own long-term strategy.
    (iii) The reasonable progress goals established by the State are
not directly enforceable but will be considered by the Administrator in
evaluating the adequacy of the measures in the implementation plan in
providing for reasonable progress towards achieving natural visibility
conditions at that area.
    (iv) In determining whether the State's goal for visibility
improvement provides for reasonable progress towards natural visibility
conditions, the Administrator will also evaluate the demonstrations
developed by the State pursuant to paragraphs (f)(2) and (f)(3)(ii)(A)
of this section and the demonstrations provided by other States
pursuant to paragraphs (f)(2) and (f)(3)(ii)(B) of this section.
    (4) If the Administrator, Regional Administrator, or the affected
Federal Land Manager has advised a State of a need for additional
monitoring to assess reasonably attributable visibility impairment at a
mandatory Class I Federal area in addition to the monitoring currently
being conducted, the State must include in the plan revision an
appropriate strategy for evaluating reasonably attributable visibility
impairment in the mandatory Class I Federal area by visual observation
or other appropriate monitoring techniques.
    (5) So that the plan revision will serve also as a progress report,
the State must address in the plan revision the requirements of
paragraphs (g)(1) through (5) of this section. However, the period to
be addressed for these elements shall be the period since the past
progress report.
    (6) Monitoring strategy and other implementation plan requirements.
The State must submit with the implementation plan a monitoring
strategy for measuring, characterizing, and reporting of regional haze
visibility impairment that is representative of all mandatory Class I
Federal areas within the State. Compliance with this requirement may be
met through participation in the Interagency Monitoring of Protected
Visual Environments network. The implementation plan must also provide
for the following:
    (i) The establishment of any additional monitoring sites or
equipment needed to assess whether reasonable progress goals to address
regional haze for all mandatory Class I Federal areas within the State
are being achieved.
    (ii) Procedures by which monitoring data and other information are
used in determining the contribution of emissions from within the State
to regional haze visibility impairment at mandatory Class I Federal
areas both within and outside the State.
    (iii) For a State with no mandatory Class I Federal areas,
procedures by which monitoring data and other information are used in
determining the contribution of emissions from within the State to
regional haze visibility impairment at mandatory Class I Federal areas
in other States.
    (iv) The implementation plan must provide for the reporting of all
visibility monitoring data to the Administrator at least annually for
each mandatory Class I Federal area in the State. To the extent
possible, the State should report visibility monitoring data
electronically.
    (v) A statewide inventory of emissions of pollutants that are
reasonably anticipated to cause or contribute to visibility impairment
in any mandatory Class I Federal area. The inventory must include
emissions for a baseline year, emissions for the most recent year for
which data are available, and estimates of future projected emissions.
The State must also include a commitment to update the inventory
periodically.
    (vi) Other elements, including reporting, recordkeeping, and other
measures, necessary to assess and report on visibility.
    (g) Requirements for periodic reports describing progress towards
the reasonable progress goals. Each State identified in Sec.  51.300(b)
must periodically submit a report to the Administrator evaluating
progress towards the reasonable progress goal for each mandatory Class
I Federal area located within the State and in each mandatory Class I
Federal area located outside the State that may be affected by
emissions from within the State. The first progress report is due 5
years from submittal of the initial implementation plan addressing
paragraphs (d) and (e) of this section. The first progress reports must
be in the form of implementation

plan revisions that comply with the procedural requirements of Sec.
51.102 and Sec.  51.103. Subsequent progress reports are due by January
31, 2025, July 31, 2033, and every 10 years thereafter. Subsequent
progress reports must be made available for public inspection and
comment for at least 60 days prior to submission to EPA and all
comments received from the public must be submitted to EPA along with
the subsequent progress report, along with an explanation of any
changes to the progress report made in response to these comments.
Periodic progress reports must contain at a minimum the following
elements:
* * * * *
    (3) For each mandatory Class I Federal area within the State, the
State must assess the following visibility conditions and changes, with
values for most impaired, least impaired and/or clearest days as
applicable expressed in terms of 5-year averages of these annual
values. The period for calculating current visibility conditions is the
most recent 5-year period preceding the required date of the progress
report for which data are available as of a date 6 months preceding the
required date of the progress report.
    (i)(A) Progress reports due before January 31, 2025. The current
visibility conditions for the most impaired and least impaired days.
    (B) Progress reports due on and after January 31, 2025. The current
visibility conditions for the most impaired and clearest days;
    (ii)(A) Progress reports due before January 31, 2025. The
difference between current visibility conditions for the most impaired
and least impaired days and baseline visibility conditions.
    (B) Progress reports due on and after January 31, 2025. The
difference between current visibility conditions for the most impaired
and clearest days and baseline visibility conditions.
    (iii)(A) Progress reports due before January 31, 2025. The change
in visibility impairment for the most impaired and least impaired days
over the period since the period addressed in the most recent plan
required under paragraph (f) of this section.
    (B) Progress reports due on and after January 31, 2025. The change
in visibility impairment for the most impaired and clearest days over
the period since the period addressed in the most recent plan required
under paragraph (f) of this section.
    (4) An analysis tracking the change over the period since the
period addressed in the most recent plan required under paragraph (f)
of this section in emissions of pollutants contributing to visibility
impairment from all sources and activities within the State. Emissions
changes should be identified by type of source or activity. With
respect to all sources and activities, the analysis must extend at
least through the most recent year for which the state has submitted
emission inventory information to the Administrator in compliance with
the triennial reporting requirements of subpart A of this part. With
respect to sources that report directly to a centralized emissions data
system operated by the Administrator, the analysis must extend through
the most recent year for which the Administrator has provided a State-
level summary of such reported data or an internet-based tool by which
the State may obtain such a summary. The State is not required to
backcast previously reported emissions to be consistent with more
recent emissions estimation procedures, and may draw attention to
actual or possible inconsistencies created by changes in estimation
procedures.
    (5) An assessment of any significant changes in anthropogenic
emissions within or outside the State that have occurred since the