
[Federal Register Volume 77, Number 39 (Tuesday, February 28, 2012)]
[Proposed Rules]
[Pages 11879-11894]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[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.

[[Page 11880]]


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: benjamin.lynorae@epa.gov.
    3. Fax: 404-562-9019.
    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 (404) 562-9061 and by 
electronic mail at waterson.sara@epa.gov. Michele Notarianni can be 
reached at telephone number (404) 562-9031 and by electronic mail at 
notarianni.michele@epa.gov.

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

[[Page 11881]]

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

[[Page 11882]]

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

[[Page 11883]]

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.

[[Page 11884]]

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

[[Page 11885]]

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

[[Page 11886]]

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

[[Page 11887]]

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

[[Page 11888]]

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

[[Page 11889]]

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.

[[Page 11890]]

 
        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

[[Page 11891]]

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

[[Page 11892]]

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''

[[Page 11893]]

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

[[Page 11894]]

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]
BILLING CODE 6560-50-P


