[Federal Register Volume 77, Number 39 (Tuesday, February 28, 2012)]
[Proposed Rules]
[Pages 11879-11894]
[FR Doc No: 2012-4661]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R04-OAR-2009-0784, FRL-9638-4]

Approval and Promulgation of Air Quality Implementation Plans;
State of Mississippi; Regional Haze State Implementation Plan

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing a limited approval of two revisions to the
Mississippi state implementation plan (SIP) submitted by the State of
Mississippi through the Mississippi Department of Environmental Quality
(MDEQ) on September 22, 2008, and May 9, 2011, that address regional
haze for the first implementation period. These revisions address the
requirements of the Clean Air Act (CAA or Act) and EPA's rules that
require states to prevent any future and remedy any existing
anthropogenic impairment of visibility in mandatory Class I areas
(national parks and wilderness areas) caused by emissions of air
pollutants from numerous sources located over a wide geographic area
(also referred to as the ``regional haze program''). States are
required to assure reasonable progress toward the national goal of
achieving natural visibility conditions in Class I areas. EPA is
proposing a limited approval of these SIP revisions to implement the
regional haze requirements for Mississippi on the basis that the
revisions, as a whole, strengthen the Mississippi SIP. EPA has
previously proposed a limited disapproval of the Mississippi regional
haze SIP because of deficiencies in the State's regional haze SIP
submittal arising from the remand by the U.S. Court of Appeals for the
District of Columbia Circuit (D.C. Circuit) to EPA of the Clean Air
Interstate Rule (CAIR). Consequently, EPA is not proposing to take
action in this rulemaking to address the State's reliance on CAIR to
meet certain regional haze requirements.

DATES: Comments must be received on or before March 29, 2012.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R04-
OAR-2009-0784, by one of the following methods:
    1. www.regulations.gov: Follow the on-line instructions for
submitting comments.
    2. Email<EMAIL_ADDRESS>    3. Fax:<PHONE_NUMBER>.
    4. Mail: EPA-R04-OAR-2009-0784, Regulatory Development Section, Air
Planning Branch, Air, Pesticides and Toxics Management Division, U.S.
Environmental Protection Agency, Region 4, 61 Forsyth Street, SW,
Atlanta, Georgia 30303-8960.
    5. Hand Delivery or Courier: Lynorae Benjamin, Chief, Regulatory
Development Section, Air Planning Branch, Air, Pesticides and Toxics
Management Division, U.S. Environmental Protection Agency, Region 4, 61
Forsyth Street, SW., Atlanta, Georgia 30303-8960. Such deliveries are
only accepted during the Regional Office's normal hours of operation.
The Regional Office's official hours of business are Monday through
Friday, 8:30 to 4:30, excluding federal holidays.
    Instructions: Direct your comments to Docket ID No. ``EPA-R04-OAR-
2009-0784.'' EPA's policy is that all comments received will be
included in the public docket without change and may be made available
online at www.regulations.gov, including any personal information
provided, unless the comment includes information claimed to be
Confidential Business Information (CBI) or other information whose
disclosure is restricted by statute. Do not submit through
www.regulations.gov or email, information that you consider to be CBI
or otherwise protected. The www.regulations.gov Web site is an
``anonymous access'' system, which means EPA will not know your
identity or contact information unless you provide it in the body of
your comment. If you send an email comment directly to EPA without
going through www.regulations.gov, your email address will be
automatically captured and included as part of the comment that is
placed in the public docket and made available on the Internet. If you
submit an electronic comment, EPA recommends that you include your name
and other contact information in the body of your comment and with any
disk or CD-ROM you submit. If EPA cannot read your comment due to
technical difficulties and cannot contact you for clarification, EPA
may not be able to consider your comment. Electronic files should avoid
the use of special characters, any form of encryption, and be free of
any defects or viruses. For additional information about EPA's public
docket visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
    Docket: All documents in the electronic docket are listed in the
www.regulations.gov index. Although listed in the index, some
information is not publicly available, i.e., CBI or other information
whose disclosure is restricted by statute. Certain other material, such
as copyrighted material, is not placed on the Internet and will be
publicly available only in hard copy form. Publicly available docket
materials are available either electronically in www.regulations.gov or
in hard copy at the Regulatory Development Section, Air Planning
Branch, Air, Pesticides and Toxics Management Division, U.S.
Environmental Protection Agency, Region 4, 61 Forsyth Street, SW,
Atlanta, Georgia 30303-8960. EPA requests that if at all possible, you
contact the person listed in the FOR FURTHER INFORMATION CONTACT
section to schedule your inspection. The Regional Office's official
hours of business are Monday through Friday, 8:30 to 4:30, excluding
federal holidays.

FOR FURTHER INFORMATION CONTACT: Sara Waterson or Michele Notarianni,
Regulatory Development Section, Air Planning Branch, Air, Pesticides
and Toxics Management Division, U.S. Environmental Protection Agency,
Region 4, 61 Forsyth Street, SW, Atlanta, Georgia 30303-8960. Sara
Waterson can be reached at telephone number<PHONE_NUMBER> and by
electronic mail at<EMAIL_ADDRESS>Michele Notarianni can be
reached at telephone number<PHONE_NUMBER> and by electronic mail at
<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

Table of Contents

I. What action is EPA proposing to take?
II. What is the background for EPA's proposed action?
    A. The Regional Haze Problem
    B. Requirements of the CAA and EPA's Regional Haze Rule (RHR)
    C. Roles of Agencies in Addressing Regional Haze
III. What are the requirements for the regional haze SIPs?
    A. The CAA and the RHR
    B. Determination of Baseline, Natural, and Current Visibility
Conditions
    C. Determination of Reasonable Progress Goals (RPGs)
    D. Best Available Retrofit Technology (BART)
    E. Long-Term Strategy (LTS)
    F. Coordinating Regional Haze and Reasonably Attributable
Visibility Impairment (RAVI) LTS
    G. Monitoring Strategy and Other Implementation Plan
Requirements
    H. Consultation With States and Federal Land Managers (FLMs)
IV. What is EPA's analysis of Mississippi's regional haze submittal?
    A. No Affected Class I Areas in Mississippi
    B. Long-Term Strategy/Strategies
    1. Emissions Inventory for 2018 With Federal and State Control
Requirements
    2. Modeling to Support the LTS and Determine Visibility
Improvement for Uniform Rate of Progress
    3. Relative Contributions to Visibility Impairment: Pollutants,
Source Categories, and Geographic Areas
    4. Procedure for Identifying Sources To Evaluate for Reasonable
Progress Controls in Mississippi and Surrounding Areas
    5. BART
    C. Coordination of RAVI and Regional Haze Requirements
    D. Monitoring Strategy and Other Implementation Plan
Requirements
    E. Consultation With States and FLMs
    1. Consultation With Other States
    2. Consultation With the FLMs
    F. Periodic SIP Revisions and Five-Year Progress Reports
V. What action is EPA taking?
VI. Statutory and Executive Order Reviews

I. What action is EPA proposing to take?

    EPA is proposing a limited approval of Mississippi's September 22,
2008, and May 9, 2011, SIP revisions addressing regional haze under CAA
sections 301(a) and 110(k)(3) because the revisions as a whole
strengthen the Mississippi SIP. Throughout this document, references to
Mississippi's (or MDEQ's or the State's) ``regional haze SIP'' refer to
Mississippi's original September 22, 2008, regional haze SIP submittal,
as later amended in a SIP revision submitted May 9, 2011. This proposed
rulemaking explains the basis for EPA's proposed limited approval
action.\1\
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    \1\ Under CAA sections 301(a) and 110(k)(6) and EPA's long-
standing guidance, a limited approval results in approval of the
entire SIP submittal, even of those parts that are deficient and
prevent EPA from granting a full approval of the SIP revision.
Processing of State Implementation Plan (SIP) Revisions, EPA
Memorandum from John Calcagni, Director, Air Quality Management
Division, OAQPS, to Air Division Directors, EPA Regional Offices I-
X, September 7, 1992, (1992 Calcagni Memorandum) located at http://www.epa.gov/ttn/caaa/t1/memoranda/siproc.pdf.
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    In a separate action, EPA has previously proposed a limited
disapproval of the Mississippi regional haze SIP because of
deficiencies in the State's regional haze SIP submittal

arising from the State's reliance on CAIR to meet certain regional haze
requirements. See 76 FR 82219 (December 30, 2011). EPA is not proposing
to take action in today's rulemaking on issues associated with
Mississippi's reliance on CAIR in its regional haze SIP.\2\ Comments on
EPA's proposed limited disapproval of Mississippi's regional haze SIP
are accepted at the docket for EPA's December 20, 2011 rulemaking (see
Docket ID No. EPA-HQ-OAR-2011-0729). The comment period for EPA's
December 30, 2011, rulemaking is scheduled to end on February 28, 2012.
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    \2\ Mississippi's SIP revisions rely on CAIR to address BART
requirements related to both nitrogen oxides (NOX) and
sulfur dioxide (SO2). However, EPA's replacement rule for
CAIR (i.e., the ``Transport Rule,'' also known as the Cross-State
Air Pollution Rule) includes Mississippi only in the trading program
to cover NOX. States such as Mississippi that are subject
to the requirements of the Transport Rule trading program only for
NOX must still address BART for SO2 and other
visibility impairing pollutants. On December 30, 2011, EPA proposed
a limited disapproval of the Mississippi regional haze SIP because
of deficiencies in the State's regional haze SIP submittal arising
from the State's reliance on CAIR to meet certain regional haze
requirements. In that action, EPA also proposed to issue a Federal
Implementation Plan (FIP) to address the deficiencies in
Mississippi's SIP associated with the BART requirements for
NOX for electrical generating units (EGUs) based on EPA's
proposed revisions to the RHR allowing states to substitute
participation in the trading programs under the Transport Rule for
source-specific BART. However, EPA did not propose a plan to address
the deficiencies associated with the BART requirements for
SO2 since the Transport Rule does not cover
SO2 emissions from Mississippi EGUs. Because Mississippi
also relied on CAIR in assessing the need for emissions reductions
for SO2 from EGUs to satisfy BART requirements, the State
will have to re-evaluate EGUs with respect to SO2 BART
requirements.
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II. What is the background for EPA's proposed action?

A. The Regional Haze Problem

    Regional haze is visibility impairment that is produced by a
multitude of sources and activities which are located across a broad
geographic area and emit fine particles (PM2.5) (e.g.,
sulfates, nitrates, organic carbon, elemental carbon, and soil dust),
and their precursors (e.g., SO2, NOX, and in some
cases, ammonia (NH3) and volatile organic compounds (VOC)).
Fine particle precursors react in the atmosphere to form fine
particulate matter which impairs visibility by scattering and absorbing
light. Visibility impairment reduces the clarity, color, and visible
distance that one can see. PM2.5 can also cause serious
health effects and mortality in humans and contributes to environmental
effects such as acid deposition and eutrophication.
    Data from the existing visibility monitoring network, the
``Interagency Monitoring of Protected Visual Environments'' (IMPROVE)
monitoring network, show that visibility impairment caused by air
pollution occurs virtually all the time at most national park and
wilderness areas. The average visual range \3\ in many Class I areas
\4\ (i.e., national parks and memorial parks, wilderness areas, and
international parks meeting certain size criteria) in the western
United States is 100-150 kilometers, or about one-half to two-thirds of
the visual range that would exist without anthropogenic air pollution.
In most of the eastern Class I areas of the United States, the average
visual range is less than 30 kilometers, or about one-fifth of the
visual range that would exist under estimated natural conditions. See
64 FR 35715 (July 1, 1999).
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    \3\ Visual range is the greatest distance, in kilometers or
miles, at which a dark object can be viewed against the sky.
    \4\ Areas designated as mandatory Class I areas consist of
national parks exceeding 6,000 acres, wilderness areas and national
memorial parks exceeding 5,000 acres, and all international parks
that were in existence on August 7, 1977. See 42 U.S.C. 7472(a). In
accordance with section 169A of the CAA, EPA, in consultation with
the Department of Interior, promulgated a list of 156 areas where
visibility is identified as an important value. See 44 FR 69122
(November 30, 1979). The extent of a mandatory Class I area includes
subsequent changes in boundaries, such as park expansions. See 42
U.S.C. 7472(a). Although states and tribes may designate as Class I
additional areas which they consider to have visibility as an
important value, the requirements of the visibility program set
forth in section 169A of the CAA apply only to ``mandatory Class I
Federal areas.'' Each mandatory Class I area is the responsibility
of a ``Federal Land Manager.'' See 42 U.S.C. 7602(i). When the term
``Class I area'' is used in this action, it means a ``mandatory
Class I Federal area.''
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B. Requirements of the CAA and EPA's Regional Haze Rule (RHR)

    In section 169A of the 1977 Amendments to the CAA, Congress created
a program for protecting visibility in the nation's national parks and
wilderness areas. This section of the CAA establishes as a national
goal the ``prevention of any future, and the remedying of any existing,
impairment of visibility in mandatory Class I areas which impairment
results from manmade air pollution.'' On December 2, 1980, EPA
promulgated regulations to address visibility impairment in Class I
areas that is ``reasonably attributable'' to a single source or small
group of sources, i.e., ``reasonably attributable visibility
impairment.'' See 45 FR 80084. These regulations represented the first
phase in addressing visibility impairment. EPA deferred action on
regional haze that emanates from a variety of sources until monitoring,
modeling, and scientific knowledge about the relationships between
pollutants and visibility impairment were improved.
    Congress added section 169B to the CAA in 1990 to address regional
haze issues. EPA promulgated a rule to address regional haze on July 1,
1999 (64 FR 35713), the RHR. The RHR revised the existing visibility
regulations to integrate into the regulation provisions addressing
regional haze impairment and established a comprehensive visibility
protection program for Class I areas. The requirements for regional
haze, found at 40 CFR 51.308 and 51.309, are included in EPA's
visibility protection regulations at 40 CFR 51.300-309. Some of the
main elements of the regional haze requirements are summarized in
section III of this preamble. The requirement to submit a regional haze
SIP applies to all 50 states, the District of Columbia, and the Virgin
Islands.\5\ 40 CFR 51.308(b) requires states to submit the first
implementation plan addressing regional haze visibility impairment no
later than December 17, 2007.
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    \5\ Albuquerque/Bernalillo County in New Mexico must also submit
a regional haze SIP to completely satisfy the requirements of
section 110(a)(2)(D) of the CAA for the entire State of New Mexico
under the New Mexico Air Quality Control Act (section 74-2-4).
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C. Roles of Agencies in Addressing Regional Haze

    Successful implementation of the regional haze program will require
long-term regional coordination among states, tribal governments, and
various Federal agencies. As noted above, pollution affecting the air
quality in Class I areas can be transported over long distances, even
hundreds of kilometers. Therefore, to effectively address the problem
of visibility impairment in Class I areas, states need to develop
strategies in coordination with one another, taking into account the
effect of emissions from one jurisdiction on the air quality in
another.
    Because the pollutants that lead to regional haze can originate
from sources located across broad geographic areas, EPA has encouraged
the states and tribes across the United States to address visibility
impairment from a regional perspective. Five regional planning
organizations (RPOs) were developed to address regional haze and
related issues. The RPOs first evaluated technical information to
better understand how their states and tribes impact Class I areas
across the country, and then pursued the development of

regional strategies to reduce emissions of particulate matter (PM) and
other pollutants leading to regional haze.
    The Visibility Improvement State and Tribal Association of the
Southeast (VISTAS) RPO is a collaborative effort of state governments,
tribal governments, and various federal agencies established to
initiate and coordinate activities associated with the management of
regional haze, visibility and other air quality issues in the
southeastern United States. Member state and tribal governments
include: Alabama, Florida, Georgia, Kentucky, Mississippi, North
Carolina, South Carolina, Tennessee, Virginia, West Virginia, and the
Eastern Band of the Cherokee Indians.

III. What are the requirements for Regional haze SIPs?

A. The CAA and the RHR

    Regional haze SIPs must assure reasonable progress towards the
national goal of achieving natural visibility conditions in Class I
areas. Section 169A of the CAA and EPA's implementing regulations
require states to establish long-term strategies for making reasonable
progress toward meeting this goal. Implementation plans must also give
specific attention to certain stationary sources that were in existence
on August 7, 1977, but were not in operation before August 7, 1962, and
require these sources, where appropriate, to install BART controls for
the purpose of eliminating or reducing visibility impairment. The
specific regional haze SIP requirements are discussed in further detail
below.

B. Determination of Baseline, Natural, and Current Visibility
Conditions

    The RHR establishes the deciview as the principal metric or unit
for expressing visibility. This visibility metric expresses uniform
changes in haziness in terms of common increments across the entire
range of visibility conditions, from pristine to extremely hazy
conditions. Visibility expressed in deciviews is determined by using
air quality measurements to estimate light extinction and then
transforming the value of light extinction using a logarithm function.
The deciview is a more useful measure for tracking progress in
improving visibility than light extinction itself because each deciview
change is an equal incremental change in visibility perceived by the
human eye. Most people can detect a change in visibility at one
deciview.\6\
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    \6\ The preamble to the RHR provides additional details about
the deciview. See 64 FR 35714, 35725 (July 1, 1999).
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    The deciview is used in expressing RPGs (which are interim
visibility goals towards meeting the national visibility goal),
defining baseline, current, and natural conditions, and tracking
changes in visibility. The regional haze SIPs must contain measures
that ensure ``reasonable progress'' toward the national goal of
preventing and remedying visibility impairment in Class I areas caused
by anthropogenic air pollution by reducing anthropogenic emissions that
cause regional haze. The national goal is a return to natural
conditions, i.e., anthropogenic sources of air pollution would no
longer impair visibility in Class I areas.
    To track changes in visibility over time at each of the 156 Class I
areas covered by the visibility program (40 CFR 81.401-437), and as
part of the process for determining reasonable progress, states must
calculate the degree of existing visibility impairment at each Class I
area at the time of each regional haze SIP submittal and periodically
review progress every five years, i.e., midway through each 10-year
implementation period. To do this, the RHR requires states to determine
the degree of impairment (in deciviews) for the average of the 20
percent least impaired (``best'') and 20 percent most impaired
(``worst'') visibility days over a specified time period at each of
their Class I areas. In addition, states must also develop an estimate
of natural visibility conditions for the purpose of comparing progress
toward the national goal. Natural visibility is determined by
estimating the natural concentrations of pollutants that cause
visibility impairment and then calculating total light extinction based
on those estimates. EPA has provided guidance to states regarding how
to calculate baseline, natural, and current visibility conditions in
documents titled, EPA's Guidance for Estimating Natural Visibility
Conditions Under the Regional Haze Rule, September 2003, (EPA-454/B-03-
005 located at http://www.epa.gov/ttncaaa1/t1/memoranda/rh_envcurhr_gd.pdf), (hereinafter referred to as ``EPA's 2003 Natural Visibility
Guidance''), and Guidance for Tracking Progress Under the Regional Haze
Rule, September 2003, (EPA-454/B-03-004 located at http://www.epa.gov/ttncaaa1/t1/memoranda/rh_tpurhr_gd.pdf), (hereinafter referred to as
``EPA's 2003 Tracking Progress Guidance'').
    For the first regional haze SIPs that were due by December 17,
2007, ``baseline visibility conditions'' were the starting points for
assessing ``current'' visibility impairment. Baseline visibility
conditions represent the degree of visibility impairment for the 20
percent least impaired days and 20 percent most impaired days for each
calendar year from 2000 to 2004. Using monitoring data for 2000 through
2004, states are required to calculate the average degree of visibility
impairment for each Class I area, based on the average of annual values
over the five-year period. The comparison of initial baseline
visibility conditions to natural visibility conditions indicates the
amount of improvement necessary to attain natural visibility, while the
future comparison of baseline conditions to the then current conditions
will indicate the amount of progress made. In general, the 2000-2004
baseline period is considered the time from which improvement in
visibility is measured.

C. Determination of Reasonable Progress Goals (RPGs)

    The vehicle for ensuring continuing progress towards achieving the
natural visibility goal is the submission of a series of regional haze
SIPs from the states that establish two RPGs (i.e., two distinct goals,
one for the ``best'' and one for the ``worst'' days) for every Class I
area for each (approximately) 10-year implementation period. The RHR
does not mandate specific milestones or rates of progress, but instead
calls for states to establish goals that provide for ``reasonable
progress'' toward achieving natural (i.e., ``background'') visibility
conditions. In setting RPGs, states must provide for an improvement in
visibility for the most impaired days over the (approximately) 10-year
period of the SIP, and ensure no degradation in visibility for the
least impaired days over the same period.
    States have significant discretion in establishing RPGs, but are
required to consider the following factors established in section 169A
of the CAA and in EPA's RHR at 40 CFR 51.308(d)(1)(i)(A): (1) The costs
of compliance; (2) the time necessary for compliance; (3) the energy
and non-air quality environmental impacts of compliance; and (4) the
remaining useful life of any potentially affected sources. States must
demonstrate in their SIPs how these factors are considered when
selecting the RPGs for the best and worst days for each applicable
Class I area. States have considerable flexibility in how they take
these factors into consideration, as noted in EPA's Guidance for
Setting Reasonable Progress Goals under the Regional Haze Program
(``EPA's Reasonable Progress Guidance''), July 1, 2007, memorandum from
William L. Wehrum, Acting Assistant Administrator for Air and
Radiation, to EPA Regional Administrators, EPA

Regions 1-10 (pp. 4-2, 5-1). In setting the RPGs, states must also
consider the rate of progress needed to reach natural visibility
conditions by 2064 (referred to as the ``uniform rate of progress'' or
the ``glidepath'') and the emissions reduction measures needed to
achieve that rate of progress over the 10-year period of the SIP.
Uniform progress towards achievement of natural conditions by the year
2064 represents a rate of progress which states are to use for
analytical comparison to the amount of progress they expect to achieve.
In setting RPGs, each state with one or more Class I areas (``Class I
state'') must also consult with potentially ``contributing states,''
i.e., other nearby states with emissions sources that may be affecting
visibility impairment at the Class I state's areas. See 40 CFR
51.308(d)(1)(iv).

D. Best Available Retrofit Technology (BART)

    Section 169A of the CAA directs states to evaluate the use of
retrofit controls at certain larger, often uncontrolled, older
stationary sources in order to address visibility impacts from these
sources. Specifically, section 169A(b)(2)(A) of the CAA requires states
to revise their SIPs to contain such measures as may be necessary to
make reasonable progress towards the natural visibility goal, including
a requirement that certain categories of existing major stationary
sources \7\ built between 1962 and 1977 procure, install, and operate
the ``Best Available Retrofit Technology'' as determined by the state.
Under the RHR, states are directed to conduct BART determinations for
such ``BART-eligible'' sources that may be anticipated to cause or
contribute to any visibility impairment in a Class I area. Rather than
requiring source-specific BART controls, states also have the
flexibility to adopt an emissions trading program or other alternative
program as long as the alternative provides greater reasonable progress
towards improving visibility than BART.
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    \7\ The set of ``major stationary sources'' potentially subject
to BART is listed in CAA section 169A(g)(7).
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    On July 6, 2005, EPA published the Guidelines for BART
Determinations Under the Regional Haze Rule at Appendix Y to 40 CFR
Part 51 (hereinafter referred to as the ``BART Guidelines'') to assist
states in determining which of their sources should be subject to the
BART requirements and in determining appropriate emissions limits for
each applicable source. In making a BART determination for a fossil
fuel-fired electric generating plant with a total generating capacity
in excess of 750 megawatts (MW), a state must use the approach set
forth in the BART Guidelines. A state is encouraged, but not required,
to follow the BART Guidelines in making BART determinations for other
types of sources.
    States must address all visibility-impairing pollutants emitted by
a source in the BART determination process. The most significant
visibility impairing pollutants are SO2, NOX, and
PM. EPA has stated that states should use their best judgment in
determining whether VOC or NH3 compounds impair visibility
in Class I areas.
    Under the BART Guidelines, states may select an exemption threshold
value for their BART modeling, below which a BART-eligible source would
not be expected to cause or contribute to visibility impairment in any
Class I area. The state must document this exemption threshold value in
the SIP and must state the basis for its selection of that value. Any
source with emissions that model above the threshold value would be
subject to a BART determination review. The BART Guidelines acknowledge
varying circumstances affecting different Class I areas. States should
consider the number of emissions sources affecting the Class I areas at
issue and the magnitude of the individual sources' impacts. Any
exemption threshold set by the state should not be higher than 0.5
deciview.
    In their SIPs, states must identify potential BART sources,
described as ``BART-eligible sources'' in the RHR, and document their
BART control determination analyses. In making BART determinations,
section 169A(g)(2) of the CAA requires that states consider the
following factors: (1) The costs of compliance, (2) the energy and non-
air quality environmental impacts of compliance, (3) any existing
pollution control technology in use at the source, (4) the remaining
useful life of the source, and (5) the degree of improvement in
visibility which may reasonably be anticipated to result from the use
of such technology. States are free to determine the weight and
significance to be assigned to each factor.
    A regional haze SIP must include source-specific BART emissions
limits and compliance schedules for each source subject to BART. Once a
state has made its BART determination, the BART controls must be
installed and in operation as expeditiously as practicable, but no
later than five years after the date of EPA approval of the regional
haze SIP. See CAA section 169(g)(4); see 40 CFR 51.308(e)(1)(iv). In
addition to what is required by the RHR, general SIP requirements
mandate that the SIP must also include all regulatory requirements
related to monitoring, recordkeeping, and reporting for the BART
controls on the source.
    As noted above, the RHR allows states to implement an alternative
program in lieu of BART so long as the alternative program can be
demonstrated to achieve greater reasonable progress toward the national
visibility goal than would BART. Under regulations issued in 2005
revising the regional haze program, EPA made just such a demonstration
for CAIR. See 70 FR 39104 (July 6, 2005). EPA's regulations provide
that states participating in the CAIR cap-and trade program under 40
CFR part 96 pursuant to an EPA-approved CAIR SIP or which remain
subject to the CAIR FIP in 40 CFR part 97 need not require affected
BART-eligible EGUs to install, operate, and maintain BART for emissions
of SO2 and NOX. See 40 CFR 51.308(e)(4). Because
CAIR did not address direct emissions of PM, states were still required
to conduct a BART analysis for PM emissions from EGUs subject to BART
for that pollutant. Challenges to CAIR, however, resulted in the remand
of the rule to EPA. See North Carolina v. EPA, 550 F.3d 1176 (DC Cir.
2008).
    EPA issued a new rule in 2011 to address the interstate transport
of NOX and SO2 in the eastern United States. See
76 FR 48208 (August 8, 2011) (``the Transport Rule,'' also known as the
Cross-State Air Pollution Rule). On December 30, 2011, EPA proposed to
find that the trading programs in the Transport Rule would achieve
greater reasonable progress towards the national goal than would BART
in the states in which the Transport Rule applies. See 76 FR 82219.
Based on this proposed finding, EPA also proposed to revise the RHR to
allow states to substitute participation in the trading programs under
the Transport Rule for source-specific BART. EPA has not yet taken
final action on that rule. Also on December 30, 2011, the DC Circuit
issued an order addressing the status of the Transport Rule and CAIR in
response to motions filed by numerous parties seeking a stay of the
Transport Rule pending judicial review. In that order, the DC Circuit
stayed the Transport Rule pending the court's resolutions of the
petitions for review of that rule in EME Homer Generation, L.P. v. EPA
(No. 11-1302 and consolidated cases). The court also indicated that EPA
is expected to continue to administer CAIR in the interim until the
court rules on the petitions for review of the Transport Rule.

E. Long-Term Strategy (LTS)

    Consistent with the requirement in section 169A(b) of the CAA that
states include in their regional haze SIP a 10 to 15 year strategy for
making reasonable progress, section 51.308(d)(3) of the RHR requires
that states include a LTS in their regional haze SIPs. The LTS is the
compilation of all control measures a state will use during the
implementation period of the specific SIP submittal to meet applicable
RPGs. The LTS must include ``enforceable emissions limitations,
compliance schedules, and other measures as necessary to achieve the
reasonable progress goals'' for all Class I areas within, or affected
by emissions from, the state. See 40 CFR 51.308(d)(3).
    When a state's emissions are reasonably anticipated to cause or
contribute to visibility impairment in a Class I area located in
another state, the RHR requires the impacted state to coordinate with
the contributing states in order to develop coordinated emissions
management strategies. See 40 CFR 51.308(d)(3)(i). In such cases, the
contributing state must demonstrate that it has included, in its SIP,
all measures necessary to obtain its share of the emissions reductions
needed to meet the RPGs for the Class I area. The RPOs have provided
forums for significant interstate consultation, but additional
consultations between states may be required to sufficiently address
interstate visibility issues. This is especially true where two states
belong to different RPOs.
    States should consider all types of anthropogenic sources of
visibility impairment in developing their LTS, including stationary,
minor, mobile, and area sources. At a minimum, states must describe how
each of the following seven factors listed below are taken into account
in developing their LTS: (1) Emissions reductions due to ongoing air
pollution control programs, including measures to address RAVI; (2)
measures to mitigate the impacts of construction activities; (3)
emissions limitations and schedules for compliance to achieve the RPG;
(4) source retirement and replacement schedules; (5) smoke management
techniques for agricultural and forestry management purposes including
plans as currently exist within the state for these purposes; (6)
enforceability of emissions limitations and control measures; and (7)
the anticipated net effect on visibility due to projected changes in
point, area, and mobile source emissions over the period addressed by
the LTS. See 40 CFR 51.308(d)(3)(v).

F. Coordinating Regional Haze and Reasonably Attributable Visibility
Impairment (RAVI) LTS

    As part of the RHR, EPA revised 40 CFR 51.306(c) regarding the LTS
for RAVI to require that the RAVI plan must provide for a periodic
review and SIP revision not less frequently than every three years
until the date of submission of the state's first plan addressing
regional haze visibility impairment, which was due December 17, 2007,
in accordance with 40 CFR 51.308(b) and (c). On or before this date,
the state must revise its plan to provide for review and revision of a
coordinated LTS for addressing RAVI and regional haze, and the state
must submit the first such coordinated LTS with its first regional haze
SIP. Future coordinated LTSs, and periodic progress reports evaluating
progress towards RPGs, must be submitted consistent with the schedule
for SIP submission and periodic progress reports set forth in 40 CFR
51.308(f) and 51.308(g), respectively. The periodic review of a state's
LTS must report on both regional haze and RAVI impairment and must be
submitted to EPA as a SIP revision.

G. Monitoring Strategy and Other Implementation Plan Requirements

    Section 51.308(d)(4) of the RHR includes the requirement for a
monitoring strategy for measuring, characterizing, and reporting of
regional haze visibility impairment that is representative of all
mandatory Class I areas within the state. The strategy must be
coordinated with the monitoring strategy required in section 51.305 for
RAVI. Compliance with this requirement may be met through
``participation'' in the IMPROVE network, i.e., review and use of
monitoring data from the network. The monitoring strategy is due with
the first regional haze SIP, and it must be reviewed every five years.
The monitoring strategy must also provide for additional monitoring
sites if the IMPROVE network is not sufficient to determine whether
RPGs will be met.
    The SIP must also provide for the following:
     Procedures for using monitoring data and other information
in a state with mandatory Class I areas to determine the contribution
of emissions from within the state to regional haze visibility
impairment at Class I areas both within and outside the state;
     Procedures for using monitoring data and other information
in a state with no mandatory Class I areas to determine the
contribution of emissions from within the state to regional haze
visibility impairment at Class I areas in other states;
     Reporting of all visibility monitoring data to the
Administrator at least annually for each Class I area in the state, and
where possible, in electronic format;
     Developing a statewide inventory of emissions of
pollutants that are reasonably anticipated to cause or contribute to
visibility impairment in any Class I 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.
A state must also make a commitment to update the inventory
periodically; and
     Other elements, including reporting, recordkeeping, and
other measures necessary to assess and report on visibility.
    The RHR requires control strategies to cover an initial
implementation period extending to the year 2018, with a comprehensive
reassessment and revision of those strategies, as appropriate, every 10
years thereafter. Periodic SIP revisions must meet the core
requirements of section 51.308(d) with the exception of BART. The
requirement to evaluate sources for BART applies only to the first
regional haze SIP. Facilities subject to BART must continue to comply
with the BART provisions of section 51.308(e), as noted above. Periodic
SIP revisions will assure that the statutory requirement of reasonable
progress will continue to be met.

H. Consultation With States and Federal Land Managers (FLMs)

    The RHR requires that states consult with FLMs before adopting and
submitting their SIPs. See 40 CFR 51.308(i). States must provide FLMs
an opportunity for consultation, in person and at least 60 days prior
to holding any public hearing on the SIP. This consultation must
include the opportunity for the FLMs to discuss their assessment of
impairment of visibility in any Class I area and to offer
recommendations on the development of the RPGs and on the development
and implementation of strategies to address visibility impairment.
Further, a state must include in its SIP a description of how it
addressed any comments provided by the FLMs. Finally, a SIP must
provide procedures for continuing consultation between the state and
FLMs regarding the state's visibility protection program, including
development and review of SIP revisions, five-year progress reports,
and the implementation of other programs

having the potential to contribute to impairment of visibility in Class
I areas.

IV. What is EPA's analysis of Mississippi's regional haze submittal?

    On September 22, 2008, and May 9, 2011, MDEQ submitted revisions to
the Mississippi SIP to address regional haze as required by EPA's RHR.

A. No Affected Class I Areas in Mississippi

    Mississippi has no Class I area within its borders. The following
Class I areas are the closest to the State's boundaries: the Breton
National Wildlife Refuge (Breton) in Louisiana, Sipsey Wilderness Area
(Sipsey) in Alabama, and Caney Creek Wilderness Area (Caney Creek) in
Arkansas. Mississippi is responsible for developing a regional haze SIP
that addresses sources within its borders that affect Class I areas in
other states and for consulting with these other states. The September
22, 2008, Mississippi regional haze SIP, as later amended on May 9,
2011, identified and considered emissions sources within Mississippi
that may cause or contribute to visibility impairment in Class I areas
in neighboring states as required by 40 CFR 51.308(d)(3). The VISTAS
RPO worked with the State in developing the technical analyses used to
make these determinations, including state-by-state contributions to
visibility impairment in specific Class I areas, which included the
Class I areas affected by emissions from Mississippi.

B. Long-Term Strategy/Strategies

    As described in section III.E of this action, the LTS is a
compilation of state-specific control measures relied on by a state for
achieving RPGs in Class I areas affected by emissions sources in the
state. Mississippi's LTS for the first implementation period addresses
the emissions reductions from federal, state, and local controls that
take effect in the State from the end of the baseline period starting
in 2004 until 2018. The Mississippi LTS was developed by the State, in
coordination with the VISTAS RPO, through an evaluation of the
following components: (1) Identification of the emissions units within
Mississippi and in surrounding states that likely have the largest
impacts currently on visibility at Class I areas in nearby states, and
(2) estimation of emissions reductions for 2018 based on all controls
required or expected under federal and state regulations for the 2004-
2018 period (including BART).
    In a separate action proposing limited disapproval of the regional
haze SIPs of a number of states, EPA noted that these states relied on
the trading programs of CAIR to satisfy the BART requirement and the
requirement for a LTS sufficient to achieve the state-adopted RPGs. See
76 FR 82219 (December 30, 2011). In that action, EPA proposed a limited
disapproval of Mississippi's regional haze SIP submittal insofar as the
SIP relied on CAIR. For that reason, EPA is not taking action on that
aspect of Mississippi's regional haze SIP in this action. Comments on
the December 30, 2011, proposed determination are accepted at Docket ID
No. EPA-HQ-OAR-2011-0729. The comment period for EPA's December 30,
2011, proposed rulemaking is scheduled to end on February 28, 2012.
1. Emissions Inventory for 2018 With Federal and State Control
Requirements
    The emissions inventory used in the regional haze technical
analyses was developed by VISTAS with assistance from Mississippi. The
2018 emissions inventory was developed by projecting 2002 emissions and
applying emissions reductions expected from federal and state
regulations affecting the emissions of VOC and the visibility-impairing
pollutants NOX, PM, and SO2. The BART Guidelines
direct states to exercise judgment in deciding whether VOC and
NH3 impair visibility in their Class I area(s). As discussed
further in section IV.B.3, VISTAS performed modeling sensitivity
analyses, which demonstrated that anthropogenic emissions of VOC and
NH3 do not significantly impair visibility in the VISTAS
region. Thus, while emissions inventories were also developed for
NH3 and VOC, and applicable Federal VOC reductions were
incorporated into Mississippi's regional haze analyses, Mississippi did
not further evaluate NH3 and VOC emissions sources for
potential controls under BART or reasonable progress.
    VISTAS developed emissions for five inventory source
classifications: stationary point and area sources, off-road and on-
road mobile sources, and biogenic sources. Stationary point sources are
those sources that emit greater than a specified tonnage per year,
depending on the pollutant, with data provided at the facility level.
Stationary area sources are those sources whose individual emissions
are relatively small, but due to the large number of these sources, the
collective emissions from the source category could be significant.
VISTAS estimated emissions on a countywide level for the inventory
categories of: (a) Stationary area sources; (b) off-road (or non-road)
mobile sources (i.e., equipment that can move but does not use the
roadways); and (c) biogenic sources (which are natural sources of
emissions, such as trees). On-road mobile source emissions are
estimated by vehicle type and road type, and are summed to the
countywide level.
    There are many federal and state control programs being implemented
that VISTAS and Mississippi anticipate will reduce emissions between
the end of the baseline period and 2018. Emissions reductions from
these control programs are projected to achieve substantial visibility
improvement by 2018 in the Class I areas in surrounding states. The
control programs relied upon by Mississippi include CAIR; EPA's
NOX SIP Call; North Carolina's Clean Smokestacks Act;
Georgia multi-pollutant rule; consent decrees for Tampa Electric,
Virginia Electric and Power Company, Gulf Power-Plant Crist, East
Kentucky Power Cooperative--Cooper and Spurlock stations, and American
Electric Power; NOX and/or VOC reductions from the control
rules in 1-hour ozone SIPs for Atlanta, Birmingham, and Northern
Kentucky; North Carolina's NOX Reasonably Available Control
Technology; state rule for Philip Morris USA and Norandal USA in the
Charlotte/Gastonia/Rock Hill 1997 8-hour ozone nonattainment area;
federal 2007 heavy duty diesel engine standards for on-road trucks and
buses; federal Tier 2 tailpipe controls for on-road vehicles; federal
large spark ignition and recreational vehicle controls; and EPA's non-
road diesel rules. Controls from various federal Maximum Achievable
Control Technology (MACT) rules were also utilized in the development
of the 2018 emissions inventory projections. These MACT rules include
the industrial boiler/process heater MACT (referred to as ``Industrial
Boiler MACT''), the combustion turbine and reciprocating internal
combustion engines MACTs, and the VOC 2-, 4-, 7-, and 10-year MACT
standards.
    Effective July 30, 2007, the DC Circuit mandated the vacatur and
remand of the Industrial Boiler MACT Rule.\8\ This MACT was vacated
since it was directly affected by the vacatur and remand of the
Commercial and Industrial Solid Waste Incinerator Definition Rule. EPA
proposed a new Industrial Boiler MACT rule to address the vacatur on
June 4, 2010 (75 FR 32006) and issued a final rule on March 21, 2011
(76 FR 15608). The VISTAS modeling included emissions reductions from
the vacated Industrial Boiler MACT rule, and

Mississippi did not redo its modeling analysis when the rule was re-
issued. Even though Mississippi's modeling is based on the vacated
Industrial Boiler MACT limits, the State's modeling conclusions are
unlikely to be affected because the expected reductions due to the
vacated rule were relatively small compared to the State's total
SO2, PM2.5, and coarse particulate matter
(PM10) emissions in 2018 (i.e., 0.1 to 0.2 percent,
depending on the pollutant, of the projected 2018 SO2,
PM2.5, and PM10 inventory). Thus, EPA does not
expect that differences between the vacated and final Industrial Boiler
MACT emissions limits would affect the adequacy of the existing
Mississippi regional haze SIP. If there is a need to address
discrepancies between projected emissions reductions from the vacated
Industrial Boiler MACT and the Industrial Boiler MACT issued March 21,
2011 (76 FR 15608), EPA expects Mississippi to do so in the State's
five-year progress report.
---------------------------------------------------------------------------

    \8\ See NRDC v. EPA, 489 F.3d 1250 (D.C. Cir. 2007).
---------------------------------------------------------------------------

    Below in Tables 2 and 3 are summaries of the 2002 baseline and 2018
estimated emissions inventories for Mississippi (based on the data in
the State's September 22, 2008, submittal).

                            Table 2--2002 Emissions Inventory Summary for Mississippi
                                                 [Tons per year]
----------------------------------------------------------------------------------------------------------------
                                                   VOC        NOX       PM2.5       PM10       NH3        SO2
----------------------------------------------------------------------------------------------------------------
Point.........................................     43,852    104,661     11,044     21,106      1,359    103,389
Area..........................................    131,808      4,200     50,401    343,377     58,721        771
On-Road Mobile................................     86,811    110,672      2,089      2,828      3,549      4,566
Non-Road Mobile...............................     41,081     88,787      4,690      5,010         23     11,315
                                               -----------------------------------------------------------------
    Total.....................................    303,552    308,320     68,224    372,321     63,652    120,041
----------------------------------------------------------------------------------------------------------------

                            Table 3--2018 Emissions Inventory Summary for Mississippi
                                                 [Tons per year]
----------------------------------------------------------------------------------------------------------------
                                                   VOC        NOX       PM2.5       PM10       NH3        SO2
----------------------------------------------------------------------------------------------------------------
Point.........................................     46,452     71,804     17,172     30,046      1,591     54,367
Area..........................................    140,134      4,483     53,222    375,495     69,910        746
On-Road Mobile................................     31,306     30,259        810      1,607      4,520        435
Non-Road Mobile...............................     28,842     68,252      3,203      3,452         29      6,638
                                               -----------------------------------------------------------------
    Total.....................................    246,734    174,798     74,407    410,600     76,050     62,186
----------------------------------------------------------------------------------------------------------------

2. Modeling To Support the LTS and Determine Visibility Improvement for
Uniform Rate of Progress
    VISTAS performed modeling for the regional haze LTS for the 10
southeastern states, including Mississippi. The modeling analysis is a
complex technical evaluation that began with selection of the modeling
system. VISTAS used the following modeling system:
     Meteorological Model: The Pennsylvania State University/
National Center for Atmospheric Research Mesoscale Meteorological Model
is a nonhydrostatic, prognostic, meteorological model routinely used
for urban- and regional-scale photochemical, PM2.5, and
regional haze regulatory modeling studies.
     Emissions Model: The Sparse Matrix Operator Kernel
Emissions modeling system is an emissions modeling system that
generates hourly gridded speciated emissions inputs of mobile, non-road
mobile, area, point, fire, and biogenic emissions sources for
photochemical grid models.
     Air Quality Model: The EPA's Models-3/Community Multiscale
Air Quality (CMAQ) modeling system is a photochemical grid model
capable of addressing ozone, PM, visibility, and acid deposition at a
regional scale. The photochemical model selected for this study was
CMAQ version 4.5. It was modified through VISTAS with a module for
Secondary Organics Aerosols in an open and transparent manner that was
also subjected to outside peer review.
    CMAQ modeling of regional haze in the VISTAS region for 2002 and
2018 was carried out on a grid of 12x12 kilometer cells that covers the
10 VISTAS states (Alabama, Florida, Georgia, Kentucky, Mississippi,
North Carolina, South Carolina, Tennessee, Virginia, West Virginia) and
states adjacent to them. This grid is nested within a larger national
CMAQ modeling grid of 36x36 kilometer grid cells that covers the
continental United States, portions of Canada and Mexico, and portions
of the Atlantic and Pacific Oceans along the east and west coasts.
Selection of a representative period of meteorology is crucial for
evaluating baseline air quality conditions and projecting future
changes in air quality due to changes in emissions of visibility-
impairing pollutants. VISTAS conducted an in-depth analysis which
resulted in the selection of the entire year of 2002 (January 1-
December 31) as the best period of meteorology available for conducting
the CMAQ modeling. The VISTAS states modeling was developed consistent
with EPA's Guidance on the Use of Models and Other Analyses for
Demonstrating Attainment of Air Quality Goals for Ozone,
PM2.5, and Regional Haze, located at http://www.epa.gov/scram001/guidance/guide/final-03-pm-rh-guidance.pdf, (EPA-454/B-07-
002), April 2007, and EPA document, Emissions Inventory Guidance for
Implementation of Ozone and Particulate Matter National Ambient Air
Quality Standards (NAAQS) and Regional Haze Regulations, located at
http://www.epa.gov/ttnchie1/eidocs/eiguid/index.html, EPA-454/R-05-001,
August 2005, updated November 2005 (``EPA's Modeling Guidance'').
    VISTAS examined the model performance of the regional modeling for
the areas of interest before determining whether the CMAQ model results
were suitable for use in the regional haze assessment of the LTS and
for use in the modeling assessment. The modeling assessment predicts
future levels of emissions and visibility impairment used to support
the LTS

and to compare predicted, modeled visibility levels with those on the
uniform rate of progress. In keeping with the objective of the CMAQ
modeling platform, the air quality model performance was evaluated
using graphical and statistical assessments based on measured ozone,
fine particles, and acid deposition from various monitoring networks
and databases for the 2002 base year. VISTAS used a diverse set of
statistical parameters from EPA's Modeling Guidance to stress and
examine the model and modeling inputs. Once VISTAS determined the model
performance to be acceptable, VISTAS used the model to assess the 2018
RPGs using the current and future year air quality modeling
predictions, and compared the RPGs to the uniform rate of progress for
Class I areas in the states neighboring Mississippi.
    In accordance with 40 CFR 51.308(d)(3), the State of Mississippi
provided the appropriate supporting documentation to VISTAS and
coordinated with other affected states for all required analyses since
there are no Class I areas in Mississippi.
3. Relative Contributions to Visibility Impairment: Pollutants, Source
Categories, and Geographic Areas
    An important step toward identifying reasonable progress measures
is to identify the key pollutants contributing to visibility impairment
at each Class I area. To understand the relative benefit of further
reducing emissions from different pollutants, source sectors, and
geographic areas, VISTAS developed emissions sensitivity model runs
using CMAQ to evaluate visibility and air quality impacts from various
groups of emissions and pollutant scenarios in the Class I areas on the
20 percent worst visibility days.
    Regarding which pollutants are most significantly impacting
visibility in the VISTAS region, VISTAS' contribution assessment, based
on IMPROVE monitoring data, demonstrated that ammonium sulfate is the
major contributor to PM2.5 mass and visibility impairment at
Class I areas in the VISTAS and neighboring states. On the 20 percent
worst visibility days in 2000-2004, ammonium sulfate accounted for 75
to 87 percent of the calculated light extinction at the inland Class I
areas in VISTAS, and 69 to 74 percent of the calculated light
extinction for all but one of the coastal Class I areas in the VISTAS
states. In contrast, ammonium nitrate contributed less than five
percent of the calculated light extinction at the VISTAS Class I areas
on the 20 percent worst visibility days. Particulate organic matter
(organic carbon) accounted for 20 percent or less of the light
extinction on the 20 percent worst visibility days at the VISTAS Class
I areas.
    VISTAS grouped its 18 Class I areas into two types, either
``coastal'' or ``inland'' (sometimes referred to as ``mountain'')
sites, based on common/similar characteristics (e.g., terrain,
geography, meteorology), to better represent variations in model
sensitivity and performance within the VISTAS region, and to describe
the common factors influencing visibility conditions in the two types
of Class I areas.
    Results from VISTAS' emissions sensitivity analyses indicate that
sulfate particles resulting from SO2 emissions are the
dominant contributor to visibility impairment on the 20 percent worst
days at all Class I areas in VISTAS. Mississippi concluded that
reducing SO2 emissions from EGU and non-EGU point sources
would have the greatest visibility benefits for the Class I areas
impacted by Mississippi sources. Because ammonium nitrate is a small
contributor to PM2.5 mass and visibility impairment on the
20 percent worst days at the inland Class I areas in VISTAS, the
benefits of reducing NOX and NH3 emissions at
these sites are small.
    The VISTAS sensitivity analyses show that VOC emissions from
biogenic sources such as vegetation also contribute to visibility
impairment. However, control of these biogenic sources of VOC would be
extremely difficult, if not impossible. The anthropogenic sources of
VOC emissions are minor compared to the biogenic sources. Therefore,
controlling anthropogenic sources of VOC emissions would have little if
any visibility benefits at the Class I areas in and adjacent to the
VISTAS region. The sensitivity analyses also show that reducing primary
carbon from point sources, ground level sources, or fires is projected
to have small to no visibility benefit at the VISTAS Class I areas.
    Mississippi considered the factors listed in under 40 CFR
51.308(d)(3)(v) and in section III.E of this action to develop its LTS
as described below. Mississippi, in conjunction with VISTAS,
demonstrated in its SIP that elemental carbon (a product of highway and
non-road diesel engines, agricultural burning, prescribed fires, and
wildfires), fine soils (a product of construction activities and
activities that generate fugitive dust), and ammonia are relatively
minor contributors to visibility impairment at the Class I areas in
states near to Mississippi. Mississippi considered agricultural and
forestry smoke management techniques to address visibility impacts from
elemental carbon. Mississippi has drafted but not finalized a Smoke
Management Plan that addresses the issues laid out in the EPA's 1998
Interim Air Quality Policy on Wildland and Prescribed Fires available
at: http://www.epa.gov/ttncaaa1/t1/memoranda/firefnl.pdf. Under current
smoke management practices, the Mississippi Forestry Commission, in
conjunction with MDEQ, issues burning permits based on daily weather
forecasts. A permit is required for any fire set for a recognized
agricultural or forestry purpose. With regard to fine soils, the State
considered those activities that generate fugitive dust, including
construction activities. Mississippi has no specific provisions to
mitigate dust emissions from construction activities. However, there
are nuisance provisions in State regulations that would apply if
construction or other activities were generating significant emissions.
Given the distance of the closest Class I area (Breton) to Mississippi,
the nuisance provisions may provide adequate control from these
activities. With regard to ammonia, the State has chosen not to develop
controls for ammonia emissions from Mississippi sources in this first
implementation period because of their relatively minor contribution to
visibility impairment.
    EPA preliminarily concurs with the State's technical demonstration
showing that elemental carbon, fine soils, and ammonia are not
significant contributors to visibility in any Class I area, and
therefore, proposes to find that Mississippi has adequately satisfied
40 CFR 51.308(d)(3)(v).
    The emissions sensitivity analyses conducted by VISTAS predict that
reductions in SO2 emissions from EGU and non-EGU industrial
point sources will result in the greatest improvements in visibility in
the Class I areas in the VISTAS region, more than any other visibility-
impairing pollutant. Additional, smaller benefits are projected from
SO2 emissions reductions from non-utility industrial point
sources. SO2 emissions contributions to visibility
impairment from other RPO regions are comparatively small in contrast
to the VISTAS states' contributions and, thus, controlling sources
outside of the VISTAS region is predicted to provide less significant
improvements in visibility in the Class I areas in VISTAS.
    SO2 sources for which it is demonstrated that no
additional controls are reasonable in this current implementation
period will not be exempted from future assessments for

controls in subsequent implementation periods or, when appropriate,
from the five-year periodic SIP reviews. In future implementation
periods, additional controls on these SO2 sources evaluated
in the first implementation period may be determined to be reasonable,
based on a reasonable progress control evaluation, for continued
progress toward natural conditions for the 20 percent worst days and to
avoid further degradation of the 20 percent best days. Similarly, in
subsequent implementation periods, the State may use different criteria
for identifying sources for evaluation and may consider other
pollutants as visibility conditions change over time.
4. Procedure for Identifying Sources to Evaluate for Reasonable
Progress Controls in Mississippi and Surrounding Areas
    As discussed in section IV.B.3. of this action, through
comprehensive evaluations by VISTAS and the Southern Appalachian
Mountains Initiative (SAMI),\9\ the VISTAS states concluded that
sulfate particles resulting from SO2 emissions account for
the greatest portion of the regional haze affecting the Class I areas
in VISTAS region and surrounding states. Utility and non-utility
boilers are the main sources of SO2 emissions within the
southeastern United States. VISTAS developed a methodology for the
VISTAS states, which enables the states to focus their reasonable
progress analyses on those geographic regions and source categories
that impact visibility at these states' Class I areas. The state in
which a Class I area is located is responsible for determining which
sources, both inside and outside of that state, to evaluate for
reasonable progress controls. Although Mississippi has no Class I
areas, at the time VISTAS was performing this analysis, many of the
surrounding states had not finalized what methodology they would use to
prioritize and identify potential sources for reasonable progress
evaluation. To assist the State to identify potential emissions units
that might be raised during the consultation process with these other
states, MDEQ applied the VISTAS methodology to identify emissions units
that could potentially warrant further analysis based on their impacts
on nearby Class I areas in neighboring states.
---------------------------------------------------------------------------

    \9\ Prior to VISTAS, the southern states cooperated in a
voluntary regional partnership ``to identify and recommend
reasonable measures to remedy existing and prevent future adverse
effects from human-induced air pollution on the air quality related
values of the Southern Appalachian Mountains.'' States cooperated
with FLMs, the EPA, industry, environmental organizations, and
academia to complete a technical assessment of the impacts of acid
deposition, ozone, and fine particles on sensitive resources in the
Southern Appalachians. The SAMI Final Report was delivered in August
2002.
---------------------------------------------------------------------------

    The State established a threshold to determine which emissions
units may be identified by neighboring states with Class I areas to be
evaluated for potential reasonable progress control depending on those
states' criteria for evaluation. In applying this methodology, MDEQ
first calculated the fractional contribution to visibility impairment
from all emissions units within the SO2 AOI for those
surrounding Class I areas in other states potentially impacted by
emissions from emissions units in Mississippi. The State then
identified those emissions units with a contribution of one percent or
more to the visibility impairment at that particular Class I area, and
evaluated each of these units for control measures for reasonable
progress, using the following four ``reasonable progress factors'' as
required under 40 CFR 51.308(d)(1)(i)(A): (1) Cost of compliance; (2)
time necessary for compliance; (3) energy and non-air quality
environmental impacts of compliance; and (4) remaining useful life of
the emissions unit.
    Mississippi's SO2 AOI methodology identified two sources
that might potentially impact the Breton Class I area: Mississippi
Power Company--Plant Watson and the DuPont Delisle facility, both in
Harrison County. Since the time of Mississippi's original 2008 SIP
submittal, Louisiana completed and submitted a regional haze SIP to
address visibility at Breton. Neither Plant Watson nor the DuPont
DeLisle facility were identified by Louisiana in consultations with
Mississippi or in the Louisiana regional haze SIP as sources identified
for reasonable progress control evaluation as sources potentially
impacting Breton. Consequently, Mississippi determined that no further
control analysis was necessary at these facilities at this time and no
controls were adopted for reasonable progress for Mississippi Power
Company--Plant Watson or the DuPont DeLisle facility during this
implementation period. Mississippi will continue to consult with
Louisiana to assess the potential impact of facilities in Mississippi
to help meet the visibility goals for Breton for future implementation
periods.
    Consistent with EPA's Reasonable Progress Guidance, since the
Breton Class I area is in Louisiana, EPA is proposing to find that
Mississippi appropriately relied on Louisiana's determination of which
sources to prioritize for reasonable progress control evaluation during
this implementation period.
5. BART
    BART is an element of Mississippi's LTS for the first
implementation period. The BART evaluation process consists of three
components: (a) An identification of all the BART-eligible sources, (b)
an assessment of whether the BART-eligible sources are subject to BART
and (c) a determination of the BART controls. These components, as
addressed by MDEQ and MDEQ's findings, are discussed as follows.

A. BART-Eligible Sources

    The first phase of a BART evaluation is to identify all the BART-
eligible sources within the State's boundaries. MDEQ identified the
BART-eligible sources in Mississippi by utilizing the three eligibility
criteria in the BART Guidelines (70 FR 39158) and EPA's regulations (40
CFR 51.301): (1) One or more emissions units at the facility fit within
one of the 26 categories listed in the BART Guidelines; (2) the
emissions units were not in operation prior to August 7, 1962, and were
in existence on August 7, 1977; and (3) these units have the potential
to emit 250 tons or more per year of any visibility-impairing
pollutant.
    The BART Guidelines also direct states to address SO2,
NOX, and direct PM (including both PM10 and
PM2.5) emissions as visibility-impairment pollutants, and to
exercise judgment in determining whether VOC or ammonia emissions from
a source impair visibility in an area. See 70 FR 39160. VISTAS modeling
demonstrated that VOC from anthropogenic sources and ammonia from point
sources are not significant visibility-impairing pollutants in
Mississippi, as discussed in section IV.B.3. of this action. MDEQ has
determined, based on the VISTAS modeling, that ammonia emissions from
the State's point sources are not anticipated to cause or contribute
significantly to any impairment of visibility in Class I areas and
should be exempt for BART purposes.

B. BART-Subject Sources

    The second phase of the BART evaluation is to identify those BART-
eligible sources that may reasonably be anticipated to cause or
contribute to visibility impairment at any Class I area, i.e., those
sources that are subject to BART. The BART Guidelines allow states to
consider exempting some BART-eligible sources from further BART review
because they may not reasonably be anticipated to cause or contribute
to any visibility impairment

in a Class I area. Consistent with the BART Guidelines, Mississippi
required each of its BART-eligible sources to develop and submit
dispersion modeling to assess the extent of their contribution to
visibility impairment at surrounding Class I areas.
1. Modeling Methodology
    The BART Guidelines allow states to use the CALPUFF \10\ modeling
system (CALPUFF) or another appropriate model to predict the visibility
impacts from a single source on a Class I area, and therefore, to
determine whether an individual source is anticipated to cause or
contribute to impairment of visibility in Class I areas, i.e., ``is
subject to BART.'' The Guidelines state that EPA believes that CALPUFF
is the best regulatory modeling application currently available for
predicting a single source's contribution to visibility impairment (70
FR 39162). Mississippi, in coordination with VISTAS, used the CALPUFF
modeling system to determine whether individual sources in Mississippi
were subject to or exempt from BART.
---------------------------------------------------------------------------

    \10\ Note that EPA's reference to CALPUFF encompasses the entire
CALPUFF modeling system, which includes the CALMET, CALPUFF, and
CALPOST models and other pre and post processors. The different
versions of CALPUFF have corresponding versions of CALMET, CALPOST,
etc. which may not be compatible with previous versions (e.g., the
output from a newer version of CALMET may not be compatible with an
older version of CALPUFF). The different versions of the CALPUFF
modeling system are available from the model developer on the
following Web site: http://www.src.com/verio/download/download.htm.
---------------------------------------------------------------------------

    The BART Guidelines also recommend that states develop a modeling
protocol for making individual source attributions and suggest that
states may want to consult with EPA and their RPO to address any issues
prior to modeling. The VISTAS states, including Mississippi, developed
a ``Protocol for the Application of CALPUFF for BART Analyses.''
Stakeholders, including EPA, FLMs, industrial sources, trade groups,
and other interested parties, actively participated in the development
and review of the VISTAS protocol.
    VISTAS developed a post-processing approach to use the new IMPROVE
equation with the CALPUFF model results so that the BART analyses could
consider both the old and new IMPROVE equations. The choice between use
of the old or the new equation for calculating the visibility metrics
for each Class I area is made by the state in which the Class I area is
located. Mississippi allowed the use of the new IMPROVE equation in
performing the screening analysis. The States of Alabama, Arkansas, and
Louisiana, whose Class I areas were potentially impacted by
Mississippi's BART sources, also allowed the use of the new IMPROVE
equation for BART analyses.
2. Contribution Threshold
    For states using modeling to determine the applicability of BART to
single sources, the BART Guidelines note that the first step is to set
a contribution threshold to assess whether the impact of a single
source is sufficient to cause or contribute to visibility impairment at
a Class I area. The BART Guidelines state that ``[a] single source that
is responsible for a 1.0 deciview change or more should be considered
to `cause' visibility impairment.'' The BART Guidelines also state that
``the appropriate threshold for determining whether a source
`contributes to visibility impairment' may reasonably differ across
states,'' but, ``[a]s a general matter, any threshold that you use for
determining whether a source `contributes' to visibility impairment
should not be higher than 0.5 deciviews.'' The Guidelines affirm that
states are free to use a lower threshold if they conclude that the
location of a large number of BART-eligible sources in proximity of a
Class I area justifies this approach.
---------------------------------------------------------------------------

    \11\ EGUs were only evaluated for PM emissions. The State relied
on CAIR to satisfy BART for SO2 and NOX for
its EGUs subject to CAIR, in accordance with 40 CFR 51.308(e)(4).
Thus, SO2 and NOX were not analyzed.
    \12\ The facility met model plant criteria as provided for in
the BART Guidelines for PM emissions only. No further modeling was
performed.
---------------------------------------------------------------------------

    Mississippi used a contribution threshold of 0.5 deciview for
determining which sources are subject to BART. The State concluded that
the threshold of 0.5 deciview, which is the highest level allowed by
the BART Guidelines, was appropriate in this situation. This threshold
of 0.5 deciview was also used by the surrounding states with Class I
areas that sources in Mississippi could impact. MDEQ concluded that a
0.5 deciview threshold was appropriate in this instance. EPA is
proposing to agree with Mississippi that the overall impacts of its
BART-eligible sources are not sufficient to warrant a lower
contribution threshold and that a 0.5 deciview threshold was
appropriate in this instance.
3. Identification of Sources Subject to BART
    Mississippi initially identified 15 facilities with BART-eligible
sources. The State subsequently determined that 13 of these sources are
exempt from being considered subject to BART. Table 5 identifies the 15
BART-eligible sources located in Mississippi and, of these, lists the
two sources subject to BART.
---------------------------------------------------------------------------

    \13\ Ibid.
    \14\ The facility met the model plant criteria as provided for
in the BART Guidelines for PM emissions only. No further modeling
was performed.

     Table 5--Mississippi BART-Eligible and Subject-to-BART Sources
------------------------------------------------------------------------

-------------------------------------------------------------------------
Facilities With Unit(s) Subject to BART:
    Chevron Products Company, Pascagoula Refinery
    Mississippi Phosphates Corporation (MPC)
Facilities With Unit(s) Found Not Subject to BART:
    EGU CAIR and BART Modeling (PM only) Exempt Sources: \11\
        Entergy Mississippi Inc, Baxter Wilson Plant
        Entergy Mississippi Inc, Gerald Andrus Plant
        Mississippi Power Company, Chevron Cogenerating Plant
        Mississippi Power Company, Plant Jack Watson
        Mississippi Power Company, Plant Victor J Daniel
        South Mississippi Electric Power Association, Moselle Plant:
         \12\
        South Mississippi Electric Power Association, R D Morrow Plant:
         \13\
    Non-EGU BART Modeling Exempt Sources
        Georgia Pacific Corp, Monticello Mill
        Greenwood Utilities, Henderson Station
        Holcim US Inc.

        International Paper Company, Vicksburg Mill
        Pursue Energy Corp, Thomasville Gas Plant
        Terra Mississippi Nitrogen Inc, Yazoo City: \14\
------------------------------------------------------------------------

    Two of the eight non-EGU facilities, Chevron Products Company--
Pascagoula Refinery and MPC, were determined to be ``subject to BART''
and were required to perform an engineering analysis, which included an
analysis of the five CAA BART factors, their evaluation of potential
BART options, and proposed BART determinations. Six of the non-EGU
sources demonstrated that they are exempt from being subject to BART.
Three of these facilities, Georgia Pacific Corp--Monticello Mill,
Holcim US Inc., and International Paper Company--Vicksburg Mill,
modeled visibility impacts of less than 0.5 deciview at the affected
Class I areas. This modeling involved assessing the visibility impact
of emissions of NOX, SO2, and PM10 as
applicable to individual facilities. The remaining facility, Terra
Mississippi Nitrogen Inc. in Yazoo City, met the model plant criteria
for exempting out of BART certain BART-eligible sources that share
specific characteristics as allowed by EPA's BART Guidelines (70 FR
39163) and no further modeling was required.
    All seven BART-eligible EGUs relied on Mississippi's decision to
rely upon CAIR emissions limits for SO2 and NOX
to satisfy their obligation to comply with BART requirements in
accordance with 40 CFR 51.308(e)(4). Therefore, these EGU sources only
modeled PM10 emissions. Five of the seven EGUs provided
modeling demonstrating that their PM10 emissions do not
contribute to visibility impairment in any Class I area. Two of the
facilities, South Mississippi Electric Power Association--Moselle Plant
and South Mississippi Electric Power Association--R D Morrow Plant, met
the model plant criteria in EPA's BART Guidelines (70 FR 39163) based
on PM emissions only and no further modeling was required.
    Prior to the CAIR remand, the State's reliance on CAIR to satisfy
BART for NOX and SO2 for affected CAIR EGUs was
fully approvable and in accordance with 40 CFR 51.308(e)(4). However,
the BART assessments for CAIR EGUs for NOX and
SO2 and other provisions in this SIP revision are based on
CAIR. In a separate action, EPA has proposed a limited disapproval of
the Mississippi regional haze SIP because of deficiencies in the
State's regional haze SIP submittal arising from the remand by the D.C.
Circuit to EPA of CAIR. See 76 FR 82219. Consequently, EPA is not
taking action in this notice to address the state's reliance on CAIR to
meet certain regional haze requirements, including BART for
SO2 and NOX emissions from EGUs.
    States such as Mississippi that are subject to the requirements of
the Transport Rule trading program only for NOX must still
address BART for SO2 and other visibility impairing
pollutants. See 76 FR at 82224. While EPA proposed on December 30,
2011, to issue a FIP to address the deficiencies in Mississippi's SIP
associated with the BART requirements for NOX for EGUs based
on EPA's proposed revisions to the RHR allowing states to substitute
participation in the trading programs under the Transport Rule for
source-specific BART, EPA did not propose a plan to address the
deficiencies associated with the BART requirements for SO2
since the Transport Rule does not cover SO2 emissions from
Mississippi EGUs. Because Mississippi also relied on CAIR in assessing
the need for emissions reductions for SO2 from EGUs to
satisfy BART, the State will have to re-evaluate EGUs with respect to
SO2 BART requirements. If EPA finalizes the limited
disapproval for Mississippi's reliance on CAIR to satisfy the regional
haze SIP requirements for SO2, that action will trigger a
24-month clock for EPA to either implement a FIP to address those
requirements or approve a revised SIP from the State that addresses
SO2 BART for its EGUs.

C. BART Determinations

    Two BART-eligible non-EGU sources (i.e., Chevron Products Company--
Pascagoula Refinery and MPC) had modeled visibility impacts of more
than the 0.5 deciview threshold for BART exemption. These two
facilities are therefore considered to be subject to BART and,
consequently, were required to perform an engineering analysis, which
included an analysis of the five CAA BART factors, their evaluation of
potential BART options, and proposed BART determinations.
    In accordance with the BART Guidelines, to determine the level of
control that represents BART for each source, the State first reviewed
existing controls on these units to assess whether these constituted
the best controls currently available, then identified what other
technically feasible controls are available, and finally, evaluated the
technically feasible controls using the five BART statutory factors.
The State's evaluations and conclusions, and EPA's assessment, are
summarized below.
1. Chevron Products Company--Pascagoula Refinery
    The modeled visibility impact resulting from Chevron Refinery's
emissions was 3.89 deciview at Breton. As stated in the State's
submittal, Chevron has significant emissions reductions planned due to
permitted projects that are currently or will soon be underway and to
an enforcement consent decree issued June 7, 2005. As a result of
ongoing and planned projects, emissions of NOX from BART
eligible sources will be reduced from 1,480 pounds per hour (lb/hr) to
521 lb/hr, SO2 emissions will be reduced from 3,154 lb/hr to
248 lb/hr, and PM10 emissions will be reduced from 187 lb/hr
to 146 lb/hr.
    For SO2, the units affected by the 2005 consent decree
emitted 3,032.7 lb/hr daily maximum average from 2001-2003, which will
be reduced by 2,884.3 lb/hr of SO2. The units involved in
Chevron's consent decree contribute 96 percent of the SO2
emissions for the refinery's BART-eligible sources. The consent decree
will reduce NOX by 960 lb/hr and PM10 by 41 lb/hr
with a modeled visibility improvement of 2.99 deciview at Breton.
    Mississippi evaluated three additional control options, two
affecting specific NOX generating units and one for
additional SO2 control. The first option (Option 1) was to
install ultra-low NOX burners (ULNB) on three of the largest
emissions units. These units are the Crude Unit 1 Vacuum Furnace (F-
1102), the Crude Unit 1 Atmospheric Furnace (F-1101), and the
Rheniformer I Reactor Furnaces (F-1501/2/3). This option could reduce
NOX emissions from these sources from 139 lb/hr to 38 lb/hr,
a reduction of 101 lb/hr, and total refinery BART-eligible source
NOX emissions would be reduced by 17 percent from the
currently planned future emissions.
    The second option (Option 2) was to also install ULNB in the
Hydrogen Plant No. 2 (F-6410) process heater. This source has a
relatively high NOX emissions rate before control on a lb/hr
basis. However, the combustion air for

this process heater is the flue gas from the associated gas turbine.
The ULNBs would only control NOX formed in the furnace.
Therefore, the estimated NOX emissions reduction is 50
percent. This option would reduce NOX emissions from this
source from 148 lb/hr to 74 lb/hr, a reduction of 74 lb/hr. By
installing ULNB in the two crude units, Rhenformer I and the hydrogen
plant, total refinery BART-eligible source NOX emissions
could be reduced by 31 percent from the currently planned future
emissions. All the other NOX sources have relatively small
emissions.
    A third option (Option 3) considered to reduce SO2
emissions is to decrease the sulfur content of the refinery fuel gas.
Currently, the hydrogen sulfide (H2S) content of the
refinery fuel gas is controlled to approximately 50 part per million by
volume (ppmv), which is well below the New Source Performance Standard
emissions limit of 162 ppmv of H2S. However, the refinery
fuel gas also contains approximately 100 ppmv of non-H2S
sulfur compounds such as various mercaptans. The Merox process could be
used to reduce the mercaptan content of the refinery fuel gas. In this
process, the mercaptans are removed with caustic-containing Merox
catalyst. Mercaptans in the rich caustic are oxidized with air to
disulfides that are decanted. The regenerated caustic is recycled. For
this analysis, 90 percent control of mercaptans was assumed. This
option would reduce SO2 emissions from 248 lb/hr to 189 lb/
hr.
    For PM10, MDEQ determined that there are no available
additional controls for refinery fuel gas combustion. Most of the other
remaining BART PM10 emissions are refinery fuel gas
combustion emissions, which comprise a small fraction of the facility's
total BART PM10 emissions.
    Capital costs range from $8.6 million for Option 1 to $40.6 million
for Option 3. Annual operating costs range from $1.3 million per year
(yr) to $5.9 million/yr. Future emissions controls already planned will
reduce the number of days greater than 1.0 deciview at Breton from 58
days to 71 days to only one to five days, depending upon the year
modeled. Similar results for the eighth highest delta deciview show a
reduction from a range of 2.9 deciviews to 3.9 deciviews for the
baseline case to only 0.7 deciview to 0.9 deciview for the future
planned case. The additional emissions reductions from the three
control options beyond the already planned emissions reductions will
provide only very small additional visibility improvements, ranging
from 0.043 deciview for Option 1 to 0.16 deciview for Option 3. For
each option, the total cost effectiveness and incremental cost
effectiveness exceed $29 million/deciview. Mississippi determined that
these further reductions would be very costly without significant
visibility improvement. Therefore, MDEQ determined that these options
are not BART due to the high cost for small visibility gains.
Mississippi has determined that the emissions controls and resulting
reductions from the consent decree constitute BART.
2. MPC
    On November 9, 2010, MPC was issued a Permit to Construct Air
Emissions Equipment that included Best Available Control Technology
(BACT) emissions limits for SO2 and sulfuric acid mist
(H2SO4). With this project, MPC is making many
upgrades, including replacing the absorption towers, installing new
economizers and new superheaters, replacing duct work and piping,
relocating new or refurbished acid coolers (i.e., heat exchangers),
repairing the cooling tower, and replacing the vanadium catalyst with
cesium catalyst in the third and fourth converter passes. These
upgrades will not result in increased sulfuric acid production
capacity, which is currently permitted at 1,800 tons per day per
sulfuric acid plant, but should allow for significant decreases in
down-time due to more reliable operation of the plants. This will
result in an actual-to-potential increase in tons per year (tpy) of
SO2; however, the project will result in greater emissions
controls and lower permitted short-term and annual emissions for both
pollutants.
    BACT for SO2 was determined to be the replacement of
vanadium catalyst with cesium catalyst in the third and fourth
converter passes. The permitted SO2 limit is 3.0 pounds (lb)
of SO2 per ton of sulfuric acid produced, not to exceed 225
lb/hr SO2 and 1,700 tpy SO2. MDEQ considers this
emissions limit appropriate as meeting BART for this source.
    BACT for H2SO4 was determined to be the
installation of vertical tube mist eliminators in the interpass
absorption tower. The final absorption tower already has these mist
eliminators installed. MPC is also replacing the economizer prior to
the final absorption tower with a larger one which will have the effect
of lowering the exhaust gas temperature and thus, reducing
H2SO4 emissions. The permitted
H2SO4 limit is 0.10 lb
H2SO4 per ton of sulfuric acid produced, not to
exceed 7.5 lb/hr H2SO4 and 32.85 tpy
H2SO4. MDEQ considers this emissions limit
appropriate as meeting BART for this source.
3. EPA Assessment
    EPA proposes to agree with Mississippi's analyses and conclusions
for the two BART-subject EGU sources described above. EPA has reviewed
the State's analyses and proposes to conclude that they were conducted
in a manner that is consistent with EPA's BART Guidelines and EPA's Air
Pollution Control Cost Manual (http://www.epa.gov/ttncatc1/products.html#cccinfo). While lower emissions limits have been
determined to be BACT for sulfuric acid plants at other facilities,
both BACT and BART are case-by-case determinations. The BACT analysis
appropriately documented that the limited additional capacities and
configuration of catalyst beds for MPC's facility limited its ability
to achieve reductions similar to those achieved at other facilities.
4. Enforceability of Emissions Limits
    The BART determinations for each of the facilities discussed above
and the resulting emissions limits are adopted by Mississippi into the
State's regional haze SIP submittal. The limits are also in consent
decrees and will be included in the facilities' title V permits. A copy
of the consent decree for Chevron Products Company--Pascagoula Refinery
was included in Appendix L of the Mississippi regional haze submittal
for informational purposes. A copy of the construction permit issued
for MPC on November 9, 2010, was included in Mississippi's supplemental
submittal of May 9, 2011, for informational purposes.

C. Coordination of RAVI and Regional Haze Requirements

    EPA's visibility regulations direct states to coordinate their RAVI
LTS and monitoring provisions with those for regional haze, as
explained in sections III.F and III.G of this action. Under EPA's RAVI
regulations, the RAVI portion of a state SIP must address any integral
vistas identified by the FLMs pursuant to 40 CFR 51.304. An integral
vista is defined in 40 CFR 51.301 as a ``view perceived from within the
mandatory Class I Federal area of a specific landmark or panorama
located outside the boundary of the mandatory Class I Federal area.''
Visibility in any mandatory Class I area includes any integral vista
associated with that area. Since there are no Class I areas in
Mississippi, no integral vistas in Mississippi have been identified. In
addition, none of its sources are affected by the RAVI provisions.
Thus, the Mississippi regional haze SIP submittal does not explicitly
address the two

requirements regarding coordination of the regional haze with the RAVI
LTS and monitoring provisions.
    In the State's submittal, MDEQ updated its visibility monitoring
program and developed a LTS to address regional haze. Also in this
submittal, MDEQ affirmed its commitment to complete items required in
the future under EPA's RHR. Specifically, MDEQ made a commitment to
review and revise its regional haze implementation plan and submit a
plan revision to EPA by July 31, 2018, and every 10 years thereafter.
See 40 CFR 51.308(f). In accordance with the requirements listed in 40
CFR 51.308(g) of EPA's regional haze regulations and 40 CFR 51.306(c)
of the RAVI LTS regulations, MDEQ made a commitment to submit a report
to EPA on progress towards the RPGs for each mandatory Class I area
located outside Mississippi which may be affected by emissions from
within Mississippi. The progress report is required to be in the form
of a SIP revision and is due every five years following the initial
submittal of the regional haze SIP. Consistent with EPA's monitoring
regulations for RAVI and regional haze, Mississippi will rely on the
IMPROVE network for compliance purposes, in addition to any RAVI
monitoring that may be needed in the future. See 40 CFR 51.305, 40 CFR
51.308(d)(4). Since there are no Class I areas in Mississippi, the
State also commits to ongoing consultation with the FLMs throughout the
implementation process, including annual discussion of the
implementation process and the most recent IMPROVE monitoring data and
VIEWS data.

D. Monitoring Strategy and Other Implementation Plan Requirements

    The primary monitoring network for regional haze in Mississippi is
the IMPROVE network. There are currently no IMPROVE sites in
Mississippi, since it has no Class I areas. In the submittal,
Mississippi states its intention to continue to consult with the FLM
annually on monitoring data from the IMPROVE network for Class I areas
in adjacent states that might be affected by Mississippi sources.
    Data produced by the IMPROVE monitoring network will be used nearly
continuously for preparing the five-year progress reports and the 10-
year SIP revisions, each of which relies on analysis of the preceding
five years of data. The Visibility Information Exchange Web System
(VIEWS) Web site has been maintained by VISTAS and the other RPOs to
provide ready access to the IMPROVE data and data analysis tools.
Mississippi is encouraging VISTAS and the other RPOs to maintain the
VIEWS or a similar data management system to facilitate analysis of the
IMPROVE data.

E. Consultation With States and FLMs

1. Consultation With Other States
    In December 2006 and in May 2007, the State Air Directors from the
VISTAS states held formal interstate consultation meetings. The purpose
of the meetings was to discuss the methodology proposed by VISTAS for
identifying sources to evaluate for reasonable progress. The states
invited FLM and EPA representatives to participate and to provide
additional feedback. The Directors discussed the results of analyses
showing contributions to visibility impairment from states to each of
the Class I areas in the VISTAS region.
    Mississippi received letters from Louisiana and Alabama
transmitting prehearing drafts of their regional haze SIPs. MDEQ
concurred on the RPGs for the Breton and Sipsey Class I areas, and
committed to continue collaboration with these states in the
preparation of future VISTAS studies and analyses and in addressing
regional haze issues in future implementation periods. EPA proposes to
find that Mississippi has adequately addressed the consultation
requirements in the RHR and appropriately documented its consultation
with other states in its SIP submittal.
2. Consultation With the FLMs
    Through the VISTAS RPO, Mississippi and the nine other member
states worked extensively with the FLMs from the U.S. Departments of
the Interior and Agriculture to develop technical analyses that support
the regional haze SIPs for the VISTAS states.
    MDEQ received comments from the U.S. Forestry Service (USFS) and
the U.S. Fish and Wildlife Service (USFWS) on the State's draft
regional haze SIP dated January 10, 2008. Appendix O of the September
22, 2008, Mississippi regional haze SIP submittal includes a summary of
the comments from the FLMs. Most of the comments were requesting
additional information or discussion on various topics which were taken
into consideration and, for the most part, included in the final
September 2008 SIP submittal. The FLMs provided comments about
including in the SIP submittal discussions on natural background,
uniform rate of progress, and RPGs for nearby Class I areas in other
states. This information was not included because Mississippi believes
that is not necessary or appropriate to present this information as
part of the Mississippi regional haze SIP.
    On March 3, 2011, the USFWS also provided comments on the draft
supplemental SIP submittal, including USFWS' views on BART for MPC and
its concerns that Louisiana's methodology for prioritizing sources for
potential reasonable progress control evaluation did not include
Mississippi's DuPont DeLisle facility. MDEQ considered these comments
in making its final determinations.

F. Periodic SIP revisions and Five-Year Progress Reports

    As also summarized in section IV.C of this action, consistent with
40 CFR 51.308(g), MDEQ affirmed its commitment to submitting a progress
report in the form of a SIP revision to EPA every five years following
this initial submittal of the Mississippi regional haze SIP. The report
will evaluate the progress made towards the RPGs for the mandatory
Class I areas located outside Mississippi which may be affected by
emissions from within Mississippi. Mississippi also offered
recommendations for several technical improvements that, as funding
allows, can support the State's next LTS.
    If another state's regional haze SIP identifies that Mississippi's
SIP needs to be supplemented or modified, and if, after appropriate
consultation Mississippi agrees, today's action may be revisited, or
additional information and/or changes will be addressed in the five-
year progress report SIP revision.

V. What action is EPA taking?

    EPA is proposing a limited approval of revisions to the Mississippi
SIP submitted by the State of Mississippi on September 22, 2008, and
May 9, 2011, as meeting some of the applicable regional haze
requirements as set forth in sections 169A and 169B of the CAA and in
40 CFR 51.300-308, as described previously in this action.

VI. Statutory and Executive Order Reviews

A. Executive Order 12866, Regulatory Planning and Review

    The Office of Management and Budget (OMB) has exempted this
regulatory action from Executive Order 12866, entitled ``Regulatory
Planning and Review.''

B. Paperwork Reduction Act

    Under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq., OMB must
approve all ``collections of information''

by EPA. The Act defines ``collection of information'' as a requirement
for answers to * * * identical reporting or recordkeeping requirements
imposed on ten or more persons * * *. 44 U.S.C. 3502(3)(A). The
Paperwork Reduction Act does not apply to this action.

C. Regulatory Flexibility Act (RFA)

    The RFA generally requires an agency to conduct a regulatory
flexibility analysis of any rule subject to notice and comment
rulemaking requirements unless the agency certifies that the rule will
not have a significant economic impact on a substantial number of small
entities. Small entities include small businesses, small not-for-profit
enterprises, and small governmental jurisdictions.
    This rule will not have a significant impact on a substantial
number of small entities because SIP approvals under section 110 and
subchapter I, part D of the CAA do not create any new requirements but
simply approve requirements that the State is already imposing.
Therefore, because the Federal SIP approval does not create any new
requirements, I certify that this action will not have a significant
economic impact on a substantial number of small entities.
    Moreover, due to the nature of the Federal-state relationship under
the CAA, preparation of a flexibility analysis would constitute Federal
inquiry into the economic reasonableness of state action. The CAA
forbids EPA to base its actions concerning SIPs on such grounds. Union
Electric Co., v. EPA, 427 U.S. 246, 255-66 (1976); 42 U.S.C.
7410(a)(2).

D. Unfunded Mandates Reform Act

    Under sections 202 of the Unfunded Mandates Reform Act of 1995
(``Unfunded Mandates Act''), signed into law on March 22, 1995, EPA
must prepare a budgetary impact statement to accompany any proposed or
final rule that includes a Federal mandate that may result in estimated
costs to State, local, or tribal governments in the aggregate, or to
the private sector, of $100 million or more. Under section 205, EPA
must select the most cost-effective and least burdensome alternative
that achieves the objectives of the rule and is consistent with
statutory requirements. Section 203 requires EPA to establish a plan
for informing and advising any small governments that may be
significantly or uniquely impacted by the rule.
    EPA has determined that today's proposal does not include a federal
mandate that may result in estimated costs of $100 million or more to
either state, local, or tribal governments in the aggregate, or to the
private sector. This Federal action proposes to approve pre-existing
requirements under State or local law, and imposes no new requirements.
Accordingly, no additional costs to State, local, or tribal
governments, or to the private sector, result from this action.

E. Executive Order 13132, Federalism

    Federalism (64 FR 43255, August 10, 1999) revokes and replaces
Executive Orders 12612 (Federalism) and 12875 (Enhancing the
Intergovernmental Partnership). Executive Order 13132 requires EPA to
develop an accountable process to ensure ``meaningful and timely input
by State and local officials in the development of regulatory policies
that have Federalism implications.'' ``Policies that have Federalism
implications'' is defined in the Executive Order to include regulations
that 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.'' Under Executive Order 13132, EPA may not issue a
regulation that has Federalism implications, that imposes substantial
direct compliance costs, and that is not required by statute, unless
the Federal government provides the funds necessary to pay the direct
compliance costs incurred by state and local governments, or EPA
consults with state and local officials early in the process of
developing the proposed regulation. EPA also may not issue a regulation
that has Federalism implications and that preempts state law unless the
Agency consults with state and local officials early in the process of
developing the proposed regulation.
    This rule 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, as specified in Executive Order 13132, because it
merely approves a state rule implementing a Federal standard, and does
not alter the relationship or the distribution of power and
responsibilities established in the CAA. Thus, the requirements of
section 6 of the Executive Order do not apply to this rule.

F. Executive Order 13175, Coordination With Indian Tribal Governments

    Executive Order 13175, entitled ``Consultation and Coordination
with Indian Tribal Governments'' (65 FR 67249, November 9, 2000),
requires EPA to develop an accountable process to ensure ``meaningful
and timely input by tribal officials in the development of regulatory
policies that have tribal implications.'' This proposed rule does not
have tribal implications, as specified in Executive Order 13175. It
will not have substantial direct effects on tribal governments. Thus,
Executive Order 13175 does not apply to this rule. EPA specifically
solicits additional comment on this proposed rule from tribal
officials.

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

    Protection of Children from Environmental Health Risks and Safety
Risks (62 FR 19885, April 23, 1997), applies to any rule that: (1) Is
determined to be ``economically significant'' as defined under
Executive Order 12866, and (2) concerns an environmental health or
safety risk that EPA has reason to believe may have a disproportionate
effect on children. If the regulatory action meets both criteria, the
Agency must evaluate the environmental health or safety effects of the
planned rule on children, and explain why the planned regulation is
preferable to other potentially effective and reasonably feasible
alternatives considered by the Agency.
    This rule is not subject to Executive Order 13045 because it does
not involve decisions intended to mitigate environmental health or
safety risks.

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

    This rule is not subject to Executive Order 13211, ``Actions
Concerning Regulations That Significantly Affect Energy Supply,
Distribution, or Use'' (66 FR 28355, May 22, 2001) because it is not a
significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act (NTTAA)

    Section 12 of the NTTAA of 1995 requires Federal agencies to
evaluate existing technical standards when developing a new regulation.
To comply with NTTAA, EPA must consider and use ``voluntary consensus
standards'' (VCS) if available and applicable when developing programs
and policies unless doing so would be inconsistent with applicable law
or otherwise impractical.
    EPA believes that VCS are inapplicable to this action. Today's
action does not require the public to

perform activities conducive to the use of VCS.

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Intergovernmental
relations, Nitrogen dioxide, Particulate matter, Reporting and
recordkeeping requirements, Sulfur oxide, Volatile organic compounds.

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

    Dated: February 15, 2012.
A. Stanley Meiburg,
Acting Regional Administrator, Region 4.
[FR Doc. 2012-4661 Filed 2-27-12; 8:45 am]
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