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[Federal Register Volume 76, Number 111 (Thursday, June 9, 2011)]
[Proposed Rules]
[Pages 33662-33685]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-14292]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R04-OAR-2009-0786-201033; FRL-9317-6]

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

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing a limited approval and a limited disapproval 
of a revision to the Tennessee State Implementation Plan (SIP) 
submitted by the State of Tennessee through the Tennessee Department of 
Environment and Conservation (TDEC) on April 4, 2008, that addresses 
regional haze for the first implementation period. This revision 
addresses the requirements of the Clean Air Act (CAA) and EPA's rules 
that require states to prevent any future and remedy any existing 
anthropogenic impairment of visibility in mandatory Class I 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 this SIP revision to 
implement the regional haze requirements for Tennessee on the basis 
that the revision, as a whole, strengthens the Tennessee SIP. Also in 
this action, EPA is proposing a limited disapproval of this same SIP 
revision because of the deficiencies in the State's April 2008 regional 
haze SIP submittal arising from the remand by the U.S. Court of Appeals 
for the District of Columbia (DC Circuit) to EPA of the Clean Air 
Interstate Rule (CAIR).

DATES: Comments must be received on or before July 11, 2011.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R04-
OAR-2009-0786, by one of the following methods:
    1. http://www.regulations.gov: Follow the on-line instructions for 
submitting comments.
    2. E-mail: spann.jane@epa.gov.
    3. Fax: 404-562-9029.
    4. Mail: EPA-R04-OAR-2009-0786, 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: Jane Spann, Acting 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-
2009-0786.'' EPA's policy is that all comments received will be 
included in the public docket without change and may be made available 
online at: http://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 http://www.regulations.gov or e-mail, information that you consider to be CBI 
or otherwise protected. The http://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 e-mail comment directly to EPA without 
going through http://www.regulations.gov, your e-mail 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 
http://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 http://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,

[[Page 33663]]

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 the relationship of the CAIR to the regional haze 
requirements?
    A. Overview of EPA's CAIR
    B. Remand of the CAIR
    C. Regional Haze SIP Elements Potentially Affected by the CAIR 
Remand
    D. Rationale and Scope of Proposed Limited Approval
V. What is EPA's analysis of Tennessee's regional haze submittal?
    A. Affected Class I Areas
    B. Determination of Baseline, Natural and Current Visibility 
Conditions
    1. Estimating Natural Visibility Conditions
    2. Estimating Baseline Conditions
    3. Summary of Baseline and Natural Conditions
    4. Uniform Rate of Progress
    C. 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 Tennessee and Surrounding Areas
    5. Application of the Four CAA Factors in the Reasonable 
Progress Analysis
    6. BART
    7. RPGs
    D. Coordination of RAVI and Regional Haze Requirements
    E. Monitoring Strategy and Other Implementation Plan 
Requirements
    F. Consultation With States and FLMs
    1. Consultation With Other States
    2. Consultation With the FLMs
    G. Periodic SIP Revisions and Five-Year Progress Reports
VI. What action is EPA proposing?
VII. Statutory and Executive Order Reviews

I. What action is EPA proposing to take?

    EPA is proposing a limited approval of Tennessee's April 4, 2008, 
SIP revision addressing regional haze under CAA sections 301(a) and 
110(k)(3) because the revision as a whole strengthens the Tennessee 
SIP. However, the Tennessee SIP relies on CAIR, an EPA rule, to satisfy 
key elements of the regional haze requirements. Due to the remand of 
CAIR, see North Carolina v. EPA, 531 F.3d 836 (DC Cir. 2008), the 
revision does not meet all of the applicable requirements of the CAA 
and EPA's regulations as set forth in sections 169A and 169B of the CAA 
and in 40 CFR 51.300-308. As a result, EPA is concurrently proposing a 
limited disapproval of Tennessee's SIP revision. The revision 
nevertheless represents an improvement over the current SIP, and makes 
considerable progress in fulfilling the applicable CAA regional haze 
program requirements. This proposed rulemaking and the accompanying 
Technical Support Document \1\ (TSD) explain the basis for EPA's 
proposed limited approval and limited disapproval actions.
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    \1\ EPA's TSD to this action, entitled, ``Technical Support 
Document for Tennessee Regional Haze Submittal,'' is included in the 
public docket for this action.
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    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. The deficiencies that EPA has identified as preventing a 
full approval of this SIP revision relate to the status and impact of 
CAIR on certain interrelated and required elements of the regional haze 
program. At the time the Tennessee regional haze SIP was being 
developed, the State's reliance on CAIR was fully consistent with EPA's 
regulations, see 70 FR 39104, 39142-4143 (July 6, 2005). CAIR, as 
originally promulgated, requires significant reductions in emissions of 
sulfur dioxide (SO2) and nitrogen oxides (NOX) to 
limit the interstate transport of these pollutants, and the reliance on 
CAIR by affected states as an alternative to requiring BART for 
electrical generating units (EGUs) had specifically been upheld in 
Utility Air Regulatory Group v. EPA, 471 F.3d 1333 (DC Cir. 2006). In 
2008, however, the DC Circuit remanded CAIR back to EPA. See North 
Carolina v. EPA, 550 F.3d 1176. The Court found CAIR to be inconsistent 
with the requirements of the CAA, see North Carolina v. EPA, 531 F.3d 
896 (DC Cir. 2008), but ultimately remanded the rule to EPA without 
vacatur because it found that ``allowing CAIR to remain in effect until 
it is replaced by a rule consistent with [the court's] opinion would at 
least temporarily preserve the environmental values covered by CAIR.'' 
North Carolina v. EPA, 550 F.3d at 1178. In response to the court's 
decision, EPA has proposed a new rule to address interstate transport 
of NOX and SO2 in the eastern United States. See 
75 FR 45210 (Aug. 2, 2010) (``the Transport Rule''). EPA explained in 
that proposal that the Transport Rule, when finalized, will replace 
CAIR and the CAIR Federal implementation plans (FIPs). In other words, 
the CAIR and CAIR FIP requirements, which were found to be illegal by 
the DC Circuit, will not remain in force after the Transport Rule 
requirements are in place. Given the status of CAIR, EPA is proposing 
to find that Tennessee may not rely on CAIR in its present form to 
provide reductions to satisfy the reasonable progress and BART 
requirements of the regional haze program.
    While CAIR will not remain in effect indefinitely, it is currently 
in force. See North Carolina v. EPA, 550 F.3d 1176. By granting limited 
approval of Tennessee's regional haze SIP, EPA will allow the State to 
rely on the emissions reductions associated with CAIR for so long as 
CAIR is in place. EPA believes that this course of action is consistent 
with the court's intention to keep CAIR in place in order to 
``temporarily preserve the environmental values covered by CAIR.'' Id, 
at 1178.

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

[[Page 33664]]

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 \2\ in many Class I areas 
(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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    \2\ Visual range is the greatest distance, in kilometers or 
miles, at which a dark object can be viewed against the sky.
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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 Federal areas \3\ 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.
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    \3\ Areas designated as mandatory Class I Federal 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 Federal 
area is the responsibility of a ``Federal Land Manager.'' See 42 
U.S.C. 7602(i). When we use the term ``Class I area'' in this 
action, we mean a ``mandatory Class I Federal area.''
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    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.\4\ 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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    \4\ Albuquerque/Bernalillo County in New Mexico must also submit 
a regional haze SIP to completely satisfy the requirements of 
section 110(a)(2)(D) of the CAA for the entire State of New Mexico 
under the New Mexico Air Quality Control Act (section 74-2-4).
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C. Roles of Agencies in Addressing Regional Haze

    Successful implementation of the regional haze program will require 
long-term regional coordination among states, tribal governments and 
various Federal agencies. As noted above, pollution affecting the air 
quality in Class I areas can be transported over long distances, even 
hundreds of kilometers. Therefore, to effectively address the problem 
of visibility impairment in Class I areas, states need to develop 
strategies in coordination with one another, taking into account the 
effect of emissions from one jurisdiction on the air quality in 
another.
    Because the pollutants that lead to regional haze can originate 
from sources located across broad geographic areas, EPA has encouraged 
the states and Tribes across the United States to address visibility 
impairment from a regional perspective. Five regional planning 
organizations (RPOs) were developed to address regional haze and 
related issues. The RPOs first evaluated technical information to 
better understand how their states and Tribes impact Class I areas 
across the country, and then pursued the development of regional 
strategies to reduce emissions of particulate matter (PM) and other 
pollutants leading to regional haze.
    The Visibility Improvement State and Tribal Association of the 
Southeast (VISTAS) RPO is a collaborative effort of state governments, 
tribal governments, and various Federal agencies established to 
initiate and coordinate activities associated with the management of 
regional haze, visibility and other air quality issues in the 
Southeastern United States. Member state and tribal governments 
include: Alabama, Florida, Georgia, Kentucky, Mississippi, North 
Carolina, South Carolina, Tennessee, Virginia, West Virginia, and the 
Eastern Band of the Cherokee Indians.

III. What are the requirements for regional haze SIPs?

A. The CAA and the RHR

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

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

    The RHR establishes the deciview as the principal metric or unit 
for expressing visibility. This visibility metric expresses uniform 
changes in haziness in terms of common

[[Page 33665]]

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.\5\
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    \5\ 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 midway through each 10-year 
implementation period. To do this, the RHR requires states to determine 
the degree of impairment (in deciviews) for the average of the 20 
percent least impaired (``best'') and 20 percent most impaired 
(``worst'') visibility days over a specified time period at each of 
their Class I areas. In addition, states must also develop an estimate 
of natural visibility conditions for the purpose of comparing progress 
toward the national goal. Natural visibility is determined by 
estimating the natural concentrations of pollutants that cause 
visibility impairment and then calculating total light extinction based 
on those estimates. EPA has provided guidance to states regarding how 
to calculate baseline, natural and current visibility conditions in 
documents titled, EPA's Guidance for Estimating Natural Visibility 
Conditions Under the Regional Haze Rule, September 2003, (EPA-454/B-03-
005 located at http://www.epa.gov/ttncaaa1/t1/memoranda/rh_envcurhr_gd.pdf), (hereinafter referred to as ``EPA's 2003 Natural Visibility 
Guidance''), and Guidance for Tracking Progress Under the Regional Haze 
Rule, September 2003, (EPA-454/B-03-004 located at http://www.epa.gov/ttncaaa1/t1/memoranda/rh_tpurhr_gd.pdf)), (hereinafter referred to as 
``EPA's 2003 Tracking Progress Guidance'').
    For the first regional haze SIPs that were due by December 17, 
2007, ``baseline visibility conditions'' were the starting points for 
assessing ``current'' visibility impairment. Baseline visibility 
conditions represent the degree of visibility impairment for the 20 
percent least impaired days and 20 percent most impaired days for each 
calendar year from 2000 to 2004. Using monitoring data for 2000 through 
2004, states are required to calculate the average degree of visibility 
impairment for each Class I area, based on the average of annual values 
over the five-year period. The comparison of initial baseline 
visibility conditions to natural visibility conditions indicates the 
amount of improvement necessary to attain natural visibility, while the 
future comparison of baseline conditions to the then current conditions 
will indicate the amount of progress made. In general, the 2000-2004 
baseline period is considered the time from which improvement in 
visibility is measured.

C. Determination of Reasonable Progress Goals (RPGs)

    The vehicle for ensuring continuing progress towards achieving the 
natural visibility goal is the submission of a series of regional haze 
SIPs from the states that establish two RPGs (i.e., two distinct goals, 
one for the ``best'' and one for the ``worst'' days) for every Class I 
area for each (approximately) 10-year implementation period. The RHR 
does not mandate specific milestones or rates of progress, but instead 
calls for states to establish goals that provide for ``reasonable 
progress'' toward achieving natural (i.e., ``background'') visibility 
conditions. In setting RPGs, states must provide for an improvement in 
visibility for the most impaired days over the (approximately) 10-year 
period of the SIP, and ensure no degradation in visibility for the 
least impaired days over the same period.
    States have significant discretion in establishing RPGs, but are 
required to consider the following factors established in section 169A 
of the CAA and in EPA's RHR at 40 CFR 51.308(d)(1)(i)(A): (1) The costs 
of compliance; (2) the time necessary for compliance; (3) the energy 
and non-air quality environmental impacts of compliance; and (4) the 
remaining useful life of any potentially affected sources. States must 
demonstrate in their SIPs how these factors are considered when 
selecting the RPGs for the best and worst days for each applicable 
Class I area. States have considerable flexibility in how they take 
these factors into consideration, as noted in EPA's Guidance for 
Setting Reasonable Progress Goals under the Regional Haze Program, 
(``EPA's Reasonable Progress Guidance''), July 1, 2007, memorandum from 
William L. Wehrum, Acting Assistant Administrator for Air and 
Radiation, to EPA Regional Administrators, EPA Regions 1-10 (pp.4-2, 5-
1). In setting the RPGs, states must also consider the rate of progress 
needed to reach natural visibility conditions by 2064 (referred to as 
the ``uniform rate of progress'' or the ``glidepath'') and the emission 
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 emission 
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 \6\ 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

[[Page 33666]]

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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    \6\ 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 emission 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, 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 emission 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 emission 
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). Since 
CAIR is not applicable to emissions of PM, states were still required 
to conduct a BART analysis for PM emissions from EGUs subject to BART 
for that pollutant.

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 emission 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) Emission 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

[[Page 33667]]

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

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

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

IV. What is the relationship of the CAIR to the regional haze 
requirements?

A. Overview of EPA's CAIR

    CAIR, as originally promulgated, requires 28 states and the 
District of Columbia to reduce emissions of SO2 and 
NOX that significantly contribute to, or interfere with 
maintenance of, the national ambient air quality standards (NAAQS) for 
fine particulates and/or ozone in any downwind state. See 70 FR 25162 
(May 12, 2005). CAIR establishes emission budgets or caps for 
SO2 and NOX for states that contribute 
significantly to nonattainment in downwind states and requires the 
significantly contributing states to submit SIP revisions that 
implement these budgets. States have the flexibility to choose which 
control measures to adopt to achieve the budgets, including 
participation in EPA-administered cap-and-trade programs addressing 
SO2, NOX -annual, and NOX -ozone 
season emissions.

B. Remand of the CAIR

    On July 11, 2008, the DC Circuit issued its decision to vacate and 
remand both CAIR and the associated CAIR FIPs in their entirety. See 
North Carolina v. EPA, 531 F.3d 836 (DC Cir. 2008). However, in 
response to EPA's petition for rehearing, the Court issued an order 
remanding CAIR to EPA without vacating either CAIR or the CAIR FIPs. 
The Court thereby left the EPA CAIR rule and CAIR SIPs and FIPs in 
place in order to ``temporarily preserve the environmental values 
covered by CAIR'' until EPA replaces it with a rule consistent with the 
court's opinion. See North Carolina v. EPA, 550 F.3d at 1178. The Court 
directed EPA to ``remedy CAIR's flaws'' consistent with its July 11, 
2008, opinion but declined to impose a schedule on EPA for completing 
that action. Because CAIR accordingly has been remanded to the Agency 
without vacatur, CAIR and the CAIR FIPs are currently in effect in 
subject states.

C. Regional Haze SIP Elements Potentially Affected by the CAIR Remand

    The following is a summary of the elements of the regional haze 
SIPs that are potentially affected by the remand of CAIR. Many states 
relied on CAIR as an alternative to BART for SO2 and 
NOX for subject EGUs, as allowed under the BART provisions 
at 40 CFR 51.308(e)(4). Additionally, several states established RPGs 
that reflect the improvement in visibility expected to result from 
controls planned for or already installed on sources within the state 
to meet the CAIR provisions for this implementation period for 
specified pollutants. Many states relied upon their own CAIR SIPs or 
the CAIR FIPs for their states to provide the legal requirements which 
leads to these planned controls, and did not include enforceable 
measures in the LTS in the regional haze SIP submission to ensure these 
reductions. States also submitted demonstrations showing that no 
additional controls on EGUs beyond CAIR would be reasonable for this 
implementation period. Due to EPA's

[[Page 33668]]

need to address the concerns of the Court as outlined in its decision 
remanding CAIR, EPA believes it would be inappropriate to fully approve 
states' LTSs that rely upon the emissions reductions predicted to 
result from CAIR to meet the BART requirement for EGUs or to meet the 
RPGs in the states' regional haze SIPs. For this reason, EPA cannot 
fully approve regional haze SIP revisions that rely on CAIR for 
emission reduction measures. EPA therefore proposes to grant limited 
approval and limited disapproval of the Tennessee SIP. The next section 
discusses how the Agency proposes to address these deficiencies.

D. Rationale and Scope of Proposed Limited Approval

    EPA is intending to propose to issue limited approvals of those 
regional haze SIP revisions that rely on CAIR to address the impact of 
emissions from a state's own EGUs. Limited approval results in approval 
of the entire regional haze submission and all its elements. EPA is 
taking this approach because an affected state's SIP will be stronger 
and more protective of the environment with the implementation of those 
measures by the state and having Federal approval and enforceability 
than it would without those measures being included in the state's SIP.
    EPA also intends to propose to issue limited disapprovals for 
regional haze SIP revisions that rely on CAIR concurrently with the 
proposals for limited approval. As explained in the 1992 Calcagni 
Memorandum, ``[t]hrough a limited approval, EPA [will] concurrently, or 
within a reasonable period of time thereafter, disapprove the rule * * 
* for not meeting all of the applicable requirements of the Act. * * * 
[T]he limited disapproval is a rulemaking action, and it is subject to 
notice and comment.'' Final limited disapproval of a SIP submittal does 
not affect the Federal enforceability of the measures in the subject 
SIP revision nor prevent state implementation of these measures. The 
legal effects of the final limited disapproval are to provide EPA the 
authority to issue a FIP at any time, and to obligate the Agency to 
take such action no more than two years after the effective date of the 
final limited disapproval action.

V. What is EPA's analysis of Tennessee's regional haze submittal?

    On April 4, 2008, TDEC's Division of Air Pollution Control 
submitted revisions to the Tennessee SIP to address regional haze in 
the State's Class I areas as required by EPA's RHR.

A. Affected Class I Areas

    Tennessee has two Class I areas within its borders: Great Smoky 
Mountains National Park and Joyce-Kilmer Slickrock Wilderness Area. 
These Class I areas also fall within the geographic boundaries of North 
Carolina. Therefore, both Tennessee and North Carolina are responsible 
for developing their own regional haze SIPs that address these Class I 
areas. The two states worked together to determine appropriate RPGs, 
including consulting with other states that impact the two Class I 
areas, as discussed in V.F.1. In addition, both Tennessee and North 
Carolina are responsible for describing their own long-term emission 
strategies, their role in the consultation processes, and how their 
particular state SIP meets the other requirements in EPA's regional 
haze regulations.
    The Tennessee regional haze SIP establishes RPGs for visibility 
improvement at each of these Class I areas and a LTS to achieve those 
RPGs within the first regional haze implementation period ending in 
2018. In developing the LTS for each area, Tennessee considered both 
emission sources inside and outside of Tennessee that may cause or 
contribute to visibility impairment in Tennessee's Class I areas. The 
State also identified and considered emission sources within Tennessee 
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 two 
areas in Tennessee and those areas affected by emissions from 
Tennessee.

B. Determination of Baseline, Natural and Current Visibility Conditions

    As required by the RHR and in accordance with EPA's 2003 Natural 
Visibility Guidance, Tennessee calculated baseline/current and natural 
visibility conditions for each of its Class I areas, as summarized 
below (and as further described in sections III.B.1 and III.B.2. of 
EPA's TSD to this Federal Register action).
1. Estimating Natural Visibility Conditions
    Natural background visibility, as defined in EPA's 2003 Natural 
Visibility Guidance, is estimated by calculating the expected light 
extinction using default estimates of natural concentrations of fine 
particle components adjusted by site-specific estimates of humidity. 
This calculation uses the IMPROVE equation, which is a formula for 
estimating light extinction from the estimated natural concentrations 
of fine particle components (or from components measured by the IMPROVE 
monitors). As documented in EPA's 2003 Natural Visibility Guidance, EPA 
allows states to use ``refined'' or alternative approaches to 2003 EPA 
guidance to estimate the values that characterize the natural 
visibility conditions of the Class I areas. One alternative approach is 
to develop and justify the use of alternative estimates of natural 
concentrations of fine particle components. Another alternative is to 
use the ``new IMPROVE equation'' that was adopted for use by the 
IMPROVE Steering Committee in December 2005.\7\ The purpose of this 
refinement to the ``old IMPROVE equation'' is to provide more accurate 
estimates of the various factors that affect the calculation of light 
extinction. Tennessee opted to use the default estimates for the 
natural concentrations combined with the ``new IMPROVE equation,'' for 
all of its areas. Using this approach, natural visibility conditions 
using the new IMPROVE equation were calculated separately for each 
Class I area by VISTAS.
---------------------------------------------------------------------------

    \7\ The IMPROVE program is a cooperative measurement effort 
governed by a steering committee composed of representatives from 
Federal agencies (including representatives from EPA and the FLMs) 
and RPOs. The IMPROVE monitoring program was established in 1985 to 
aid the creation of Federal and State implementation plans for the 
protection of visibility in Class I areas. One of the objectives of 
IMPROVE is to identify chemical species and emission sources 
responsible for existing anthropogenic visibility impairment. The 
IMPROVE program has also been a key participant in visibility-
related research, including the advancement of monitoring 
instrumentation, analysis techniques, visibility modeling, policy 
formulation and source attribution field studies.
---------------------------------------------------------------------------

    The new IMPROVE equation takes into account the most recent review 
of the science \8\ and it accounts for the

[[Page 33669]]

effect of particle size distribution on light extinction efficiency of 
sulfate, nitrate, and organic carbon. It also adjusts the mass 
multiplier for organic carbon (particulate organic matter) by 
increasing it from 1.4 to 1.8. New terms are added to the equation to 
account for light extinction by sea salt and light absorption by 
gaseous nitrogen dioxide. Site-specific values are used for Rayleigh 
scattering (scattering of light due to atmospheric gases) to account 
for the site-specific effects of elevation and temperature. Separate 
relative humidity enhancement factors are used for small and large size 
distributions of ammonium sulfate and ammonium nitrate and for sea 
salt. The terms for the remaining contributors, elemental carbon 
(light-absorbing carbon), fine soil, and coarse mass terms, do not 
change between the original and new IMPROVE equations.
---------------------------------------------------------------------------

    \8\ The science behind the revised IMPROVE equation is 
summarized in Appendix B.2 of the Tennessee Regional Haze submittal 
and in numerous published papers. See for example: Hand, J.L., and 
Malm, W.C., 2006, Review of the IMPROVE Equation for Estimating 
Ambient Light Extinction Coefficients--Final Report. March 2006. 
Prepared for Interagency Monitoring of Protected Visual Environments 
(IMPROVE), Colorado State University, Cooperative Institute for 
Research in the Atmosphere, Fort Collins, Colorado. http://vista.cira.colostate.edu/improve/publications/GrayLit/016_IMPROVEeqReview/IMPROVEeqReview.htm; and Pitchford, Marc., 2006, 
Natural Haze Levels II: Application of the New IMPROVE Algorithm to 
Natural Species Concentrations Estimates. Final Report of the 
Natural Haze Levels II Committee to the RPO Monitoring/Data Analysis 
Workgroup. September 2006 http://vista.cira.colostate.edu/improve/Publications/GrayLit/029_NaturalCondII/naturalhazelevelsIIreport.ppt.
---------------------------------------------------------------------------

2. Estimating Baseline Conditions
    The Joyce Kilmer-Slickrock Wilderness Area does not contain an 
IMPROVE monitor. In cases where onsite monitoring is not available, 40 
CFR 51.308(d)(2)(i) requires states to use the most representative 
monitoring available for the 2000-2004 period to establish baseline 
visibility conditions, in consultation with EPA. Tennessee used and EPA 
concurs with the use of 2000-2004 data from the IMPROVE monitor at 
Great Smoky Mountains National Park for the Joyce Kilmer-Slickrock 
Wilderness Area. The Great Smoky Mountains National Park is nearest and 
contiguous to the Joyce Kilmer-Slickrock Wilderness Area, and the areas 
possess similar characteristics, such as meteorology and topography.
    TDEC estimated baseline visibility conditions at both Tennessee 
Class I areas using available monitoring data from a single IMPROVE 
monitoring site in the Great Smoky Mountains National Park. As 
explained in section III.B, for the first regional haze SIP, baseline 
visibility conditions are the same as current conditions. A five-year 
average of the 2000 to 2004 monitoring data was calculated for each of 
the 20 percent worst and 20 percent best visibility days at each 
Tennessee Class I area. IMPROVE data records for Great Smoky Mountains 
National Park for the period 2000 to 2004 meet the EPA requirements for 
data completeness. See page 2-8 of EPA's 2003 Tracking Progress 
Guidance. Table 3.3-1 from Appendix G of the Tennessee regional haze 
SIP, also provided in section III.B.3 of EPA's TSD to this action, 
lists the 20 percent best and worst days for the baseline period of 
2000-2004 for Great Smoky Mountains National Park. This data is also 
provided at the following Web site: http://www.metro4-sesarm.org/vistas/SesarmBext_20BW.htm.
3. Summary of Baseline and Natural Conditions
    For the Tennessee Class I areas, baseline visibility conditions on 
the 20 percent worst days are approximately 30 deciviews. Natural 
visibility in these areas is predicted to be approximately 11 deciviews 
on the 20 percent worst days. The natural and baseline conditions for 
Tennessee's Class I areas for both the 20 percent worst and best days 
are presented in Table 1 below.
---------------------------------------------------------------------------

    \9\ The term, ``dv,'' is the abbreviation for ``deciview.''

  Table 1--Natural Background and Baseline Conditions for the Tennessee
                              Class I Areas
------------------------------------------------------------------------
                                          Average for 20  Average for 20
              Class I area                 percent worst   percent best
                                           days (dv \9\)     days (dv)
------------------------------------------------------------------------
Natural Background Conditions:
    Great Smoky Mountains National Park.           11.05            4.54
    Joyce Kilmer-Slickrock Wilderness              11.05            4.54
     Area...............................
Baseline Visibility Conditions (2000-
 2004):
    Great Smoky Mountains National Park.           30.28           13.58
    Joyce Kilmer-Slickrock Wilderness              30.28           13.58
     Area...............................
------------------------------------------------------------------------

4. Uniform Rate of Progress
    In setting the RPGs, Tennessee considered the uniform rate of 
progress needed to reach natural visibility conditions by 2064 
(``glidepath'') and the emission reduction measures needed to achieve 
that rate of progress over the period of the SIP to meet the 
requirements of 40 CFR 51.308(d)(1)(i)(B). As explained in EPA's 
Reasonable Progress Guidance document, the uniform rate of progress is 
not a presumptive target, and RPGs may be greater, lesser, or 
equivalent to the glidepath.
    The State's implementation plan presents two sets of graphs, one 
for the 20 percent best days, and one for the 20 percent worst days, 
for its two Class I areas. Tennessee constructed the graph for the 
worst days (i.e., the glidepath) in accordance with EPA's 2003 Tracking 
Progress Guidance by plotting a straight graphical line from the 
baseline level of visibility impairment for 2000-2004 to the level of 
visibility conditions representing no anthropogenic impairment in 2064 
for its two areas. For the best days, the graph includes a horizontal, 
straight line spanning from baseline conditions in 2004 out to 2018 to 
depict no degradation in visibility over the implementation period of 
the SIP. Tennessee's SIP shows that the State's RPGs for its areas 
provide for improvement in visibility for the 20 percent worst days 
over the period of the implementation plan and ensure no degradation in 
visibility for the 20 percent best days over the same period, in 
accordance with 40 CFR 51.308(d)(1).
    For the Tennessee Class I areas, the overall visibility improvement 
necessary to reach natural conditions is the difference between 
baseline visibility of 30.28 deciviews for the 20 percent worst days 
and natural conditions of 11.05 deciviews, i.e., 19.23 deciviews. Over 
the 60-year period from 2004 to 2064, this would require an average 
improvement of 0.321 deciviews per year to reach natural conditions. 
Hence, for the 14-year period from 2004 to 2018, in order to achieve 
visibility improvements at least equivalent to the uniform rate of 
progress for the 20 percent worst days at Great Smoky Mountain National 
Park and the Joyce Kilmer-Slickrock Wilderness Area, Tennessee would 
need to project at least 4.49 deciviews over the first implementation 
period (i.e., 0.321 deciviews x 14 years = 4.49 deciviews) of 
visibility improvement from the 30.28 deciviews baseline in 2004, 
resulting in visibility levels at or below 25.79 deciviews in 2018. As 
discussed below in section V.C.7,

[[Page 33670]]

``Reasonable Progress Goals,'' Tennessee projects a 6.78 deciview 
improvement to visibility from the 30.28 deciview baseline to 23.50 
deciviews in 2018 for the 20 percent most impaired days, and a 1.47 
deciview improvement to 12.11 deciviews from the baseline visibility of 
13.58 deciviews for the 20 percent least impaired days.

C. 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 the state 
for achieving its RPGs. Tennessee'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 Tennessee LTS was 
developed by the State, in coordination with the VISTAS RPO, through an 
evaluation of the following components: (1) Identification of the 
emission units within Tennessee and in surrounding states that likely 
have the largest impacts currently on visibility at the State's two 
Class I areas; (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); (3) comparison of projected 
visibility improvement with the uniform rate of progress for the 
State's Class I areas; and (4) application of the four statutory 
factors in the reasonable progress analysis for the identified emission 
units to determine if additional reasonable controls were required.
    CAIR is also an element of Tennessee's LTS. CAIR rule revisions 
were approved into the Tennessee SIP in 2007 and 2009. See 72 FR 46388 
(Aug. 20, 2007); 74 FR 61535 (Nov. 25, 2009). Tennessee opted to rely 
on CAIR emission reduction requirements to satisfy the BART 
requirements for SO2 and NOX from EGUs. See 40 
CFR 51.308(e)(4). Therefore, Tennessee only required its BART-eligible 
EGUs to evaluate PM emissions for determining whether they are subject 
to BART, and, if applicable, for performing a BART control assessment. 
See section III.D. of this notice for further details. Additionally, as 
discussed below in section V.C.5, Tennessee concluded that no 
additional controls beyond CAIR are reasonable for reasonable progress 
for its EGUs for this first implementation period. Prior to the remand 
of CAIR, EPA believed the State's reliance on CAIR for specific BART 
and reasonable progress provisions affecting its EGUs was adequate, as 
detailed later in this notice. As explained in section IV. of this 
notice, the Agency proposes today to issue a limited approval and a 
proposed limited disapproval of the State's regional haze SIP revision.
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 Tennessee. The 
2018 emissions inventory was developed by projecting 2002 emissions and 
applying 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 V.C.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 
Tennessee's regional haze analyses, Tennessee 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 Tennessee anticipate will reduce emissions between the 
end of the baseline period and 2018. Emission reductions from these 
control programs are projected to achieve substantial visibility 
improvement by 2018 in the Tennessee Class I areas. The control 
programs relied upon by Tennessee 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, 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 (2007) 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 emission 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.
    On July 30, 2007, the U.S. District Court of Appeals mandated the 
vacatur and remand of the Industrial Boiler MACT Rule.\10\ This MACT 
was vacated since it was directly affected by the vacatur and remand of 
the Commercial and Industrial Solid Waste Incinerator (CISWI) 
Definition Rule. Notwithstanding the vacatur of this rule, the VISTAS 
states, including Tennessee, decided to leave these controls in the 
modeling for their regional haze SIPs since it is believed that by 
2018, EPA will have re-promulgated an industrial boiler MACT rule or 
the states will have addressed the issue through state-level case-by-
case MACT reviews in accordance with section 112(j) of the CAA. EPA 
finds this approach acceptable for the following reasons. 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), giving Tennessee time to assure the required controls are in 
place prior to the end of the first implementation period in 2018. In 
the absence of an established MACT rule for boilers and process 
heaters, the statutory language in section 112(j) of the CAA specifies 
a

[[Page 33671]]

schedule for the incorporation of enforceable MACT-equivalent limits 
into the title V operating permits of affected sources. Should 
circumstances warrant the need to implement section 112(j) of the CAA 
for industrial boilers, EPA would expect, in this case, that compliance 
with case-by-case MACT limits for industrial boilers would occur no 
later than January 2015, which is well before the 2018 RPGs for 
regional haze. In addition, the RHR requires that any resulting 
differences between emissions projections and actual emissions 
reductions that may occur will be addressed during the five-year review 
prior to the next 2018 regional haze SIP. The expected reductions due 
to the original, vacated Industrial Boiler MACT rule were relatively 
small compared to the State's total SO2, PM2.5, 
and coarse particulate matter (PM10) emissions in 2018 
(i.e., 0.5 to 1.5 percent, depending on the pollutant, of the projected 
2018 SO2, PM2.5, and PM10 inventory), 
and not likely to affect any of Tennessee's modeling conclusions. Thus, 
if there is a need to address discrepancies such that projected 
emissions reductions from the vacated Industrial Boiler MACT were 
greater than actual reductions achieved by the replacement MACT, EPA 
would not expect that this would affect the adequacy of the existing 
Tennessee regional haze SIP.
---------------------------------------------------------------------------

    \10\ See NRDC v. EPA, 489F.3d 1250.
---------------------------------------------------------------------------

    Below in Tables 2 and 3 are summaries of the 2002 baseline and 2018 
estimated emission inventories for Tennessee.

                             Table 2--2002 Emissions Inventory Summary for Tennessee
                                                 [Tons per year]
----------------------------------------------------------------------------------------------------------------
                                        VOC          NOX         PM2.5         PM10         NH3          SO2
----------------------------------------------------------------------------------------------------------------
Point.............................       85,254      221,651       39,973       49,814        1,817      413,755
Area..............................      153,509       17,936       42,925      212,972       34,412       29,942
On-Road Mobile....................      179,807      238,577        3,949        5,371        6,625        9,226
Off-Road Mobile...................       66,450       96,827        6,458        6,819           43       10,441
                                   -----------------------------------------------------------------------------
    Total.........................      485,020      574,991       93,305      274,976       42,897      463,364
----------------------------------------------------------------------------------------------------------------

                             Table 3--2018 Emissions Inventory Summary for Tennessee
                                                 [Tons per year]
----------------------------------------------------------------------------------------------------------------
                                        VOC          NOX         PM2.5         PM10         NH3          SO2
----------------------------------------------------------------------------------------------------------------
Point.............................       93,432       94,234       46,680       57,940        2,454      169,354
Area..............................      183,110       20,002       48,265      248,086       36,376       32,073
On-Road Mobile....................       67,324       69,385        1,544        3,092        9,021          948
Off-road Mobile...................       45,084       70,226        4,403        4,672           55        5,207
                                   -----------------------------------------------------------------------------
    Total.........................      388,950      253,847      100,892      313,790       47,906      207,582
----------------------------------------------------------------------------------------------------------------

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 Tennessee. 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 emission inputs of mobile, non-road 
mobile, area, point, fire and biogenic emission 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, PM 
2.5, 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'').

[[Page 33672]]

    VISTAS examined the model performance of the regional modeling for 
the areas of interest before determining whether the CMAQ model results 
were suitable for use in the regional haze assessment of the LTS and 
for use in the modeling assessment. The modeling assessment predicts 
future levels of emissions and visibility impairment used to support 
the LTS and to compare predicted, modeled visibility levels with those 
on the uniform rate of progress. In keeping with the objective of the 
CMAQ modeling platform, the air quality model performance was evaluated 
using graphical and statistical assessments based on measured ozone, 
fine particles, and acid deposition from various monitoring networks 
and databases for the 2002 base year. VISTAS used a diverse set of 
statistical parameters from the 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.
    In accordance with 40 CFR 51.308(d)(3), the State of Tennessee 
provided the appropriate supporting documentation for all required 
analyses used to determine the State's LTS. The technical analyses and 
modeling used to develop the glidepath and to support the LTS are 
consistent with EPA's RHR, and interim and final EPA Modeling Guidance. 
EPA accepts the VISTAS technical modeling to support the LTS and 
determine visibility improvement for the uniform rate of progress 
because the modeling system was chosen and simulated according to EPA 
Modeling Guidance. EPA agrees with the VISTAS model performance 
procedures and results, and that the CMAQ is an appropriate tool for 
the regional haze assessments for the Tennessee LTS and regional haze 
SIP.
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 emission 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 
greater than 70 percent of the calculated light extinction at Class I 
areas in the Southern Appalachians. In particular, for Great Smoky 
Mountains National Park, sulfate particles resulting from 
SO2 emissions contribute roughly 84 percent to the 
calculated light extinction on the haziest days. In contrast, ammonium 
nitrate contributed less than five percent of the calculated light 
extinction at VISTAS Class I areas on the 20 percent worst visibility 
days. Particulate organic matter (organic carbon) accounted for 10-20 
percent of light extinction on the 20 percent worst visibility days.
    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. Tennessee's Class I areas are both ``inland'' areas.
    Results from VISTAS' emission 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, including the two Tennessee areas. 
Tennessee concluded that reducing SO2 emissions from EGU and 
non-EGU point sources in the VISTAS states would have the greatest 
visibility benefits for the Tennessee Class I areas. 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, which include Joyce-Kilmer Wilderness Area and Great Smoky 
Mountains National Park, 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 the VISTAS region, 
including Tennessee. 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.
    Tennessee 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. Tennessee, 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 Tennessee. Tennessee 
considered agricultural and forestry smoke management techniques to 
address visibility impacts from elemental carbon. TDEC is currently 
working with the Tennessee Division of Forestry to develop a smoke 
management program that utilizes basic smoke management practices and 
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. With regard to fine 
soils, the State considered those activities that generate fugitive 
dust, including construction activities. With regard to construction 
activities, the Tennessee Department of Transportation has agreed to 
include discussions related to the control of road construction project 
dust emissions as part of its contract bid specifications. In addition, 
TDEC's Rule 1200-3-8-.03 requires additional control measures in air 
source operating permits to control dust emissions. The State has 
chosen not to develop controls for fine soils in this first 
implementation period because of its relatively minor contribution to 
visibility impairment. With regard to ammonia emissions from 
agricultural sources, TDEC will wait for the results of emissions 
sampling and Best Management Practices arising from EPA's Combined 
Animal Feeding Operation Consent Order Agreements prior to initiating 
any control measures for agricultural ammonia. EPA concurs with the 
State's technical demonstration

[[Page 33673]]

showing that elemental carbon, fine soils and ammonia are not 
significant contributors to visibility in the State's Class I areas, 
and therefore, finds that Tennessee has adequately satisfied 40 CFR 
51.308(d)(3)(v). EPA's TSD to this Federal Register action and 
Tennessee's SIP provide more details on the State's consideration of 
these factors for Tennessee's LTS.
    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. Specific to Tennessee, the VISTAS sensitivity 
analysis projects visibility benefits in Great Smoky Mountains National 
Park and Joyce-Kilmer Slickrock Wilderness Area from SO2 
reductions from EGUs in eight of the 10 VISTAS states: Alabama, 
Georgia, Kentucky, North Carolina, South Carolina, Tennessee, Virginia, 
and West Virginia. Additional, smaller benefits are projected from 
SO2 emission 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.
    Taking the VISTAS sensitivity analyses results into consideration, 
Tennessee concluded that reducing SO2 emissions from EGU and 
non-EGU point sources in certain VISTAS states would have the greatest 
visibility benefits for the Tennessee Class I areas. The State chose to 
focus solely on evaluating certain SO2 sources contributing 
to visibility impairment to the State's Class I areas for additional 
emission reductions for reasonable progress in this first 
implementation period (described in sections V.4. and V.5. of this 
notice). EPA agrees with the State's analyses and conclusions used to 
determine the pollutants and source categories that most contribute to 
visibility impairment in the Tennessee Class I areas, and finds the 
State's approach to focus on developing a LTS that includes largely 
additional measures for point sources of SO2 emissions to be 
appropriate.
    SO2 sources for which it is demonstrated that no 
additional controls are reasonable in this current implementation 
period will not be exempted from future assessments for controls in 
subsequent implementation periods or, when appropriate, from the five-
year periodic SIP reviews. In future implementation periods, additional 
controls on these SO2 sources evaluated in the first 
implementation period may be determined to be reasonable, based on a 
reasonable progress control evaluation, for continued progress toward 
natural conditions for the 20 percent worst days and to avoid further 
degradation of the 20 percent best days. Similarly, in subsequent 
implementation periods, the State may use different criteria for 
identifying sources for evaluation and may consider other pollutants as 
visibility conditions change over time.
4. Procedure for Identifying Sources To Evaluate for Reasonable 
Progress Controls in Tennessee and Surrounding Areas
    As discussed in section V.C.3. of this notice, through 
comprehensive evaluations by VISTAS and the Southern Appalachian 
Mountains Initiative (SAMI),\11\ 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 states, including those in Tennessee. Utility and non-utility 
boilers are the main sources of SO2 emissions within the 
southeastern United States. VISTAS developed a methodology for 
Tennessee, which enables the State to focus its reasonable progress 
analysis on those geographic regions and source categories that impact 
visibility at each of its Class I areas. Recognizing that there was 
neither sufficient time nor adequate resources available to evaluate 
all emission units within a given area of influence (AOI) around each 
Class I area that Tennessee's sources impact, the State established a 
threshold to determine which emission units would be evaluated for 
reasonable progress control. In applying this methodology, TDEC first 
calculated the fractional contribution to visibility impairment from 
all emission units within the SO2 AOI for each of its Class 
I areas, and those surrounding areas in other states potentially 
impacted by emissions from emission units in Tennessee. The State then 
identified those emission 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): (i) Cost of compliance; (ii) 
time necessary for compliance; (iii) energy and non-air quality 
environmental impacts of compliance; and (iv) remaining useful life of 
the emission unit.
---------------------------------------------------------------------------

    \11\ 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 USEPA, 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.
---------------------------------------------------------------------------

    Tennessee's SO2 AOI methodology captured greater than 60 
percent of the total point source SO2 contribution to 
visibility impairment in the two Class I areas in Tennessee, and 
required an evaluation of 15 emission units. Capturing a significantly 
greater percentage of the total contribution would involve an 
evaluation of many more emission units that have substantially less 
impact. EPA believes the approach developed by VISTAS and implemented 
for the Class I areas in Tennessee is a reasonable methodology to 
prioritize the most significant contributors to regional haze and to 
identify sources to assess for reasonable progress control in the 
State's Class I areas. The approach is consistent with EPA's Reasonable 
Progress Guidance. The technical approach of VISTAS and Tennessee was 
objective and based on several analyses, which included a large 
universe of emission units within and surrounding the State of 
Tennessee and all of the 18 VISTAS Class I areas. It also included an 
analysis of the VISTAS emission units affecting nearby Class I areas 
surrounding the VISTAS states that are located in other RPOs' Class I 
areas.
5. Application of the Four CAA Factors in the Reasonable Progress 
Analysis
    TDEC identified 15 emission units at 10 facilities in Tennessee 
(see Table 4) with SO2 emissions that were above the State's 
minimum threshold for reasonable progress evaluation because they were 
modeled to fall within the sulfate AOI of any Class I area and have a 
one percent or greater contribution to the sulfate visibility 
impairment to at least one Class I area.\12\ Of these 15 units, 13 
emission units were exempted from preparing a reasonable progress 
analysis because they were already subject to BART or CAIR, had shut 
down, or provided additional information documenting that they had been 
improperly identified as meeting

[[Page 33674]]

the State's minimum threshold for reasonable progress evaluation.
---------------------------------------------------------------------------

    \12\ See also EPA's TSD, section III.C.2, fractional 
contribution analysis tables for each Class I area, excerpted from 
the Tennessee SIP, Appendix H.

  Table 4--Tennessee Facilities Subject to Reasonable Progress Analysis
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Facilities With a Unit Subject to Reasonable Progress Analysis:
    Bowater Newsprint and Directory--Calhoun (Bowater), Unit 015
    Invista--Hixon/Chattanooga (INVISTA), Unit 0002
Facilities With Unit(s) Exempt from Reasonable Progress Analysis:
    EGUs Subject to BART and CAIR
        Tennessee Valley Authority--Cumberland Facility, Units 001, 002
        Tennessee Valley Authority--Bull Run Facility, Unit 001
    Non-EGUs Subject to BART
        Alcoa--South Plant, Units 09, 16, 17
        Eastman Chemical Company Units 021520, 020101, 261501
    Shut down Facility
        Intertrade Holdings, Inc.
    Exempted With Updated Information
        A.E. Staley Manufacturing Company
        APAC-TN, Inc./Harrison Construction Division
        U.S. DOE--Y-12 Plant
------------------------------------------------------------------------

A. Facilities With an Emissions Unit Subject to Reasonable Progress 
Analysis

    TDEC analyzed whether SO2 controls should be required 
for two facilities, Bowater Newsprint and Directory--Calhoun, unit 015 
(Bowater), and Invista-Hixson/Chattanooga, unit 0002 (INVISTA), based 
on a consideration of the four factors set out in the CAA and EPA's 
regulations. For the limited purpose of evaluating the cost of 
compliance for the reasonable progress assessment in this first 
regional haze SIP for the non-EGUs, TDEC concluded that it was not 
equitable to require non-EGUs to bear a greater economic burden than 
EGUs for a given control strategy. Using the CAIR rule as a guide, a 
cost of $2,000 per ton of SO2 controlled or reduced was used 
as a determiner of cost effectiveness.
1. Bowater
    Bowater is a Kraft pulp mill with three coal-fired boilers burning 
1.1 percent sulfur coal. Bowater presented information and data in its 
reasonable progress control analysis that led TDEC to conclude that 
Bowater should not be required to install SO2 post-
combustion controls or to switch to lower sulfur fuels during this 
first regional haze SIP implementation period. Bowater evaluated 
switching to a lower sulfur (0.6 percent) western sub-bituminous coal 
and determined that it is not technologically feasible since Bowater's 
boilers were designed to burn eastern bituminous coal, and the 
different physical properties (e.g., ash fusion temperature, etc.) of 
western sub-bituminous coal make its use incompatible with the Bowater 
boilers. Bowater also evaluated installing SO2 wet 
scrubbers, which is technically feasible, but the estimated cost-
effectiveness exceeds $5,000 per ton of SO2 removed, which 
exceeds the State's $2,000 cost-effectiveness threshold for 
reasonableness. Other environmental factors affecting the application 
of wet scrubbers are the water scarcity in the local area due to 
seasonal droughts and the treatment and disposal of wastewater and 
sludge.
2. INVISTA
    INVISTA produces polymers and fibers and operates three coal-fired 
boilers. SO2 emissions from these boilers averaged 944 tons 
per year over three years (2004, 2005, and 2006). The current title V 
permit limits coal sulfur content to 1.25 percent; however, actual 
sulfur content has averaged nearly 1.0 percent over these three years. 
INVISTA evaluated the following options: low sulfur coals, wet Flue Gas 
Desulfurization (FGD) System (wet scrubbers), Spray Dryer Absorber 
(SDA) System, Fluidized Bed Combustion (FBC) with Limestone, and Dry 
Sorbent Injection (DSI) System. Of these options, only low sulfur coal 
fell below the $2,000 per ton cost threshold TDEC used to determine 
reasonableness.
    A wet FGD system was determined to be a technically feasible option 
for control of SO2 emissions from the boilers used by 
INVISTA, but cost prohibitive. Cost-effectiveness was calculated to be 
approximately $3,508 per ton of SO2 removed, which exceeds 
the State's cost threshold for reasonableness. In assessing other 
environmental impacts, the company raised the possibility of causing a 
steam plume from the installation of a scrubber. It is not known 
whether the possible presence of a persistent, highly opaque steam 
plume from the scrubbers' stacks would be an issue. If it is, 
additional costs would be incurred from installing a separate stack to 
address this problem.
    Similarly, an SDA system was determined to be a technically 
feasible control option but also cost prohibitive. The cost-
effectiveness of applying SDA to this unit is estimated to be at least 
$4,000 per ton of SO2 removed. In addition, this option has 
the potential to result in an overall ash with properties so different 
from the current ash that it will no longer be acceptable for sale to 
cement kilns. If that becomes the case, INVISTA would be required to 
truck the ash offsite for disposal in a landfill at a substantial 
increase in cost relative to the current disposal cost.
    As was the case for FGD and SDA, TDEC determined that the DSI 
system was also technically feasible but cost prohibitive as a control 
option. The cost-effectiveness of applying DSI was estimated to be at 
least $4,037 per ton of SO2 removed. As with SDA, this 
option could result in an overall ash with properties so different from 
the ash that is currently produced that it will no longer be acceptable 
for sale to cement kilns. If that becomes the case, INVISTA would be 
required to truck the ash offsite for disposal in a landfill at a 
substantial increase in cost relative to the current disposal cost.
    Finally, INVISTA evaluated switching to a lower sulfur (0.75 
percent) western sub-bituminous coal, and determined that this is both 
a technologically feasible and cost effective control technology 
option. The cost-effectiveness was calculated to be approximately 
$1,225 per ton of SO2 removed. The decrease in 
SO2 emissions from the facility's baseline by switching to 
lower sulfur coal was calculated to be approximately 214 tons of 
SO2 per year. INVISTA concluded that the cost of switching 
to a lower sulfur coal would

[[Page 33675]]

cost more than the $2,000 per ton used by TDEC to determine 
reasonableness of control costs and therefore, it was a cost 
prohibitive option. INVISTA based its conclusion on research that 
demonstrated that the $1,225 per ton control cost used by TDEC was 
unjustifiable because it was based on the current cost of low sulfur 
coal instead of the future costs it would be expected to pay. Taking 
into consideration INVISTA's entire analysis, TDEC agreed that although 
fuel-switching seemed to be a favored option among a number of sources, 
the future cost of coal switching at the INVISTA facility may be cost 
prohibitive. For this reason, TDEC is deferring a decision to require 
INVISTA to use the fuel-switching option during this implementation 
period.
3. EPA Assessment
    As noted in EPA's Reasonable Progress Guidance, the states have 
wide latitude to determine appropriate additional control requirements 
for ensuring reasonable progress, and there are many ways for a state 
to approach identification of additional reasonable measures. In 
determining reasonable progress, states must consider, at a minimum, 
the four statutory factors, but states have flexibility in how to take 
these factors into consideration.
    Tennessee applied the methodology developed by VISTAS for 
identifying appropriate sources to be considered for additional 
controls under reasonable progress for the implementation period 
addressed by this SIP, which ends in 2018. Using this methodology, TDEC 
first identified those emissions and emissions units most likely to 
have an impact on visibility in the State's Class I areas. Units with 
emissions of SO2 with a relative contribution to visibility 
impairment of at least a one percent contribution at any Class I area 
were then subject to further analysis to determine whether it would be 
appropriate to require controls on these units for purposes of 
reasonable progress. As noted above, of the emission units in 
Tennessee, two were subject to this analysis. TDEC concluded, based on 
their evaluation of these two facilities, Bowater and INVISTA, that no 
further controls were warranted at this time.
    Having reviewed TDEC's methodology and analyses presented in the 
SIP materials prepared by TDEC, EPA is proposing to approve Tennessee's 
conclusion that no further controls are reasonable for this 
implementation period for the reviewed sources. EPA agrees with the 
State's approach of identifying the key pollutants contributing to 
visibility impairment at its Class I areas, and consider their 
methodology to identify sources of SO2 most likely to have 
an impact on visibility on any Class I area, to be an appropriate 
methodology for narrowing the scope of the State's analysis. In 
general, EPA also finds Tennessee's evaluation of the four statutory 
factors for reasonable progress to be reasonable. Although the use of a 
specific threshold for assessing costs means that Tennessee may not 
have fully considered other available emissions reduction measures 
above their threshold, EPA believes that the Tennessee SIP still 
ensures reasonable progress. EPA notes that given the emissions 
reductions resulting from CAIR, Tennessee's BART determinations, and 
the measures in nearby states, the visibility improvements projected 
for the affected Class I areas are in excess of that needed to be on 
the uniform rate of progress glidepath. In considering Tennessee's 
approach, EPA is also proposing to place great weight on the fact that 
there is no indication in the SIP submittal that Tennessee, as a result 
of using a specific cost effectiveness threshold, rejected potential 
reasonable progress measures that would have had a meaningful impact on 
visibility in its Class I areas.
    EPA also finds that TDEC's conclusion regarding the fuel switching 
option evaluated for INVISTA acceptable. Although the $1,225 per ton of 
SO2 reduced is below the cost-effectiveness threshold 
established by TDEC, a 214 ton per year reduction in SO2 is 
expected to produce limited visibility improvement at the only Class I 
area that INVISTA impacts (Cohutta Wilderness Class I Area in Georgia) 
and is therefore an acceptable basis for deferral of consideration of 
additional controls to the next assessment period. In addition, EPA 
finds that Tennessee fully evaluated, in terms of the four reasonable 
progress factors, all control technologies available at the time of its 
analysis and applicable to these facilities. EPA also finds that 
Tennessee consistently applied its criteria for reasonable compliance 
costs, and where it differed, the State included justification for the 
other factors influencing the control determination.

B. Emission Units Exempted From Preparing a Reasonable Progress Control 
Analysis

1. EGUs Subject to BART and CAIR
    Three of the 15 emission units identified for a reasonable progress 
control analysis are EGUs. These three EGUs are subject to CAIR and 
were also found to be subject to BART, as discussed in section V.C.6. 
These three EGUs, located at two facilities, are Tennessee Valley 
Authority \13\ (TVA) Bull Run Fossil Plant, unit 001, and TVA 
Cumberland Fossil Plant, units 001 and 002.
---------------------------------------------------------------------------

    \13\ On April 14, 2011, a landmark CAA settlement was achieved 
with TVA involving 59 units across the TVA system. Information on 
the settlement may be obtained at: http://yosemite.epa.gov/opa/admpress.nsf/2467feca60368729852573590040443d/45cbf1a4262af67b8525787200516dd7!OpenDocument. This settlement will 
assure that these facilities have controls consistent with Best 
Available Control Technology.
---------------------------------------------------------------------------

    To determine whether any additional controls beyond those required 
by CAIR would be considered reasonable for Tennessee's EGUs for this 
first implementation period, TDEC evaluated the SO2 
reductions expected from the EGU sector, factoring in updated 
information provided by TVA, which owns and operates the EGUs in 
Tennessee. The EGUs located in Tennessee are expected to reduce their 
2002 SO2 emissions by approximately 75 percent by 2018. TDEC 
believes it has an accurate understanding of where EGU emission 
reductions will occur in Tennessee based upon existing and planned 
installations of post combustion FGD scrubber controls.
    To further evaluate whether CAIR requirements will satisfy 
reasonable progress for SO2 for EGUs, TDEC considered the 
four reasonable progress factors set forth in EPA's RHR as they apply 
to the State's entire EGU sector for available control technologies in 
section 7.6 of the Tennessee SIP. The State also reviewed CAIR 
requirements that include 2015 as the ``earliest reasonable deadline 
for compliance'' for EGUs installing retrofits. See 70 FR 25162, 25197-
25198 (May 12, 2005). This is a particularly relevant consideration 
because CAIR addresses the reasonable progress factors of cost and time 
necessary for compliance. In the preamble to CAIR, EPA recognized there 
are a number of factors that influence compliance with the emission 
reduction requirements set forth in CAIR, which make the 2015 
compliance date reasonable. For example, each EGU retrofit requires a 
large pool of specialized labor resources, which exist in limited 
quantities. In addition, retrofitting an EGU is a very capital-
intensive venture and therefore undertaken with caution. Hence, 
allowing retrofits to be installed over time enables the industry to 
learn from early installations. Lastly, EGU retrofits over time 
minimize disruption of the power grid by enabling industry to take 
advantage of planned outages.

[[Page 33676]]

    Since EPA made the determination in CAIR that the earliest 
reasonable deadline for compliance for reducing emissions was 2015, 
TDEC concluded that the emission reductions required by CAIR constitute 
reasonable measures for Tennessee EGUs during this first assessment 
period (between baseline and 2018). In addition, TDEC notes that while 
the reasonable progress evaluation only applies to existing sources, 
the State will continue to follow the visibility analysis requirements 
as part of all new major source review (NSR) and prevention of 
significant deterioration (PSD) permitting actions.
    Prior to the CAIR remand by the DC Circuit, EPA believed the 
State's demonstration that no additional controls beyond CAIR are 
reasonable for SO2 for affected EGUs for the first 
implementation period to be acceptable on the basis that the CAIR 
requirements reflected the most cost-effective controls that can be 
achieved over the CAIR SO2 compliance timeframe, which spans 
out to 2015. However, as explained in section IV of this notice, the 
State's demonstration regarding CAIR and reasonable progress for EGUs, 
and other provisions in this SIP revision, are based on CAIR and thus, 
the Agency proposes today to issue a limited approval and a limited 
disapproval of the State's regional haze SIP revision.
2. Non-EGUs Subject to BART
    Six of the 15 non-EGU emission units in Tennessee falling within 
the sulfate AOI of a Class I area are industrial facilities that TDEC 
found to be also subject to BART: Aluminum Company of America (Alcoa)--
South Plant, units 09, 16, 17, and Eastman Chemical Company, units 
021520, 020101, 261501. TDEC has concluded that, for this 
implementation period, the application of BART constitutes reasonable 
progress for these six units and thus, is not requiring any additional 
controls for reasonable progress. As discussed in EPA's Reasonable 
Progress Guidance, since the BART analysis is based, in part, on an 
assessment of many of the same factors that must be addressed in 
establishing the RPG, EPA believes it is reasonable to conclude that 
any control requirements imposed in the BART determination also satisfy 
the RPG-related requirements for source review in the first 
implementation period.\14\ Thus, EPA agrees with the State's 
conclusions that the BART control evaluations satisfy reasonable 
progress for the first implementation period for these six non-EGU 
emission units at Alcoa and Eastman Chemical.
---------------------------------------------------------------------------

    \14\ EPA's Reasonable Progress Guidance, pages 4.2-4-3.
---------------------------------------------------------------------------

3. Other Units Exempted From Preparing a Reasonable Progress Control 
Analysis
    Four other facilities have emission units that were later 
determined to be exempt from preparing a reasonable progress control 
analysis. The emission unit 001 at Intertrade Holdings, Inc. that was 
to be considered for evaluation for reasonable progress shut down prior 
to analysis. In addition, TDEC identified three emission units that 
should not have been included on the list of sources to evaluate 
because updated information showed they did not meet Tennessee's 
minimum threshold for evaluation for reasonable progress control. A.E. 
Staley Manufacturing (now Tate & Lyle) Company, unit 005, was already 
subject to emission limits contained in a construction permit issued 
March 9, 2007, that reduces SO2 emissions from unit 005, the 
power boiler, by approximately 62 percent. APAC-TN, Inc./Harrison 
Construction Division, unit 002, was erroneously modeled at almost 10 
times its allowable emission rate. Finally, unit 002 (coal-fired 
boilers) at the U.S. Department of Energy's Y-12 Plant was repowered to 
operate on natural gas, virtually eliminating its SO2 
emissions.
6. BART
    BART is an element of Tennessee'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 
TDEC and TDEC'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. TDEC identified the 
BART-eligible sources in Tennessee 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 emission units at the facility fit within 
one of the 26 categories listed in the BART Guidelines; (2) emission 
unit(s) was constructed on or after August 6, 1962, and was in 
existence prior to August 6, 1977; and (3) potential emissions of any 
visibility-impairing pollutant from subject units are 250 tons or more 
per year.
    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. 70 FR 39160. VISTAS modeling 
demonstrated that VOC from anthropogenic sources and ammonia from point 
sources are not significant visibility-impairing pollutants in 
Tennessee, as discussed in section V.C.3. of this action. TDEC has 
determined, based on the VISTAS modeling, that with one exception (PCS 
Nitrogen facility near Memphis, Tennessee), ammonia emissions from the 
State's point sources are not anticipated to cause or contribute 
significantly to any impairment of visibility in Class I areas and 
should be exempt for BART purposes.

B. BART-Subject Sources

    The second phase of the BART evaluation is to identify those BART-
eligible sources that may reasonably be anticipated to cause or 
contribute to visibility impairment at any Class I area, i.e., those 
sources that are subject to BART. The BART Guidelines allow states to 
consider exempting some BART-eligible sources from further BART review 
because they may not reasonably be anticipated to cause or contribute 
to any visibility impairment in a Class I area. Consistent with the 
BART Guidelines, Tennessee 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 \15\ modeling 
system (CALPUFF) or another appropriate model to predict the visibility 
impacts from a single source on a Class I area and to therefore, 
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 CALPUFF is 
the best regulatory modeling application currently available for 
predicting a single source's

[[Page 33677]]

contribution to visibility impairment (70 FR 39162). Tennessee, in 
coordination with VISTAS, used the CALPUFF modeling system to determine 
whether individual sources in Tennessee were subject to or exempt from 
BART.
---------------------------------------------------------------------------

    \15\ Note that our 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 Tennessee, 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. TDEC sent a letter to 
EPA justifying the need for this post-processing approach, and the EPA 
Region 4 Regional Administrator sent the State a letter of approval 
dated October 5, 2007. Tennessee's justification included a method to 
process the CALPUFF output and a rationale on the benefits of using the 
new IMPROVE equation. The State's description of the new post-
processing methodology and the State and Region 4 letters are located 
in the Tennessee regional haze SIP submittal and the docket for this 
action.
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.
    Tennessee used a contribution threshold of 0.5 deciview for 
determining which sources are subject to BART. EPA agrees with the 
State's rationale for choosing this threshold value. There are a 
limited number of BART-eligible sources in close proximity to each of 
the State's Class I areas, and the overall impact of the BART-eligible 
sources on visibility near Class I areas is relatively minimal. In 
addition, the results of the visibility impacts modeling demonstrated 
that the majority of the individual BART-eligible sources had 
visibility impacts well below 0.5 deciview.
    TDEC demonstrated that there is a clear spatial separation of 
sources across the State and little risk of multiple source 
interactions. For example, there are no clusters of Tennessee BART-
eligible sources near the Great Smoky Mountains and Joyce Kilmer Class 
I areas. In addition, only two sources, TVA-Bull Run and Alcoa, are 
located within 32 kilometers from each other and the remainder of the 
State's BART-eligible sources are over 100 kilometers from one another 
with respect to these Class I areas. Similarly, with regard to Class I 
areas in nearby states, Tennessee's BART sources are all located 
greater than 180 kilometers from the Class I areas of Mingo Wilderness 
(MO), Sipsey Wilderness (AL), and Mammoth Cave (KY).
3. Identification of Sources Subject to BART
    Tennessee initially identified 16 facilities with BART-eligible 
sources. The State subsequently determined that four sources are exempt 
from being considered BART-eligible. Liberty Fibers Corporation has 
permanently shut down, and the BART-eligible boilers located at the 
facility have been dismantled. Intertrade Holdings, Inc. has 
permanently shut down the acid plant that was determined to be BART-
eligible. Similarly, the power boiler at the Weyerhaeuser facility 
(formerly Willamette Industries) in Sullivan County has been retired 
and is no longer BART-eligible. Finally, Holston Army Ammunition Plant 
requested and was issued an operating permit (February 25, 2008) with a 
249 tons per year Federally enforceable emission limit for 
NOX for the eight emission units that make up their acid 
plant which enabled it to exempt these units from consideration as a 
BART-eligible source. Table 5 identifies the remaining 12 BART-eligible 
sources located in Tennessee, and identifies the four sources subject 
to BART.

[[Page 33678]]

      Table 5--Tennessee BART-Eligible and Subject-to-BART Sources
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Facilities With Unit(s) Subject to BART Analysis:
    Alcoa--South Plant
    Eastman Chemical Company--Tennessee Operations
    E.I. DuPont de Nemours and Company, Inc. (Old Hickory)
    TVA--Cumberland Fossil Plant
Facilities With Unit(s) Found Not Subject to BART:
    EGU CAIR and BART Modeling (PM only) Sources \16\
        TVA--Bull Run Fossil Plant
    Non-EGU BART Modeling
        E.I. DuPont de Nemours and Company, Inc. (Shelby County)
        DuPont White Pigment and Mineral Products (Humphreys County)
        Lucite International
        Owens Corning
        Packaging Corporation of America
        PCS Nitrogen
        Zinifex
------------------------------------------------------------------------

    Tennessee found that four of its BART-eligible sources (i.e., 
Alcoa--South Plant, Eastman Chemical Company--Tennessee Operations, 
DuPont--Old Hickory and TVA--Cumberland Fossil Plant) had modeled 
visibility impacts of more than the 0.5 deciview threshold for BART 
exemption. These four facilities are considered to be subject to BART 
and submitted State permit applications including their proposed BART 
determinations.
---------------------------------------------------------------------------

    \16\ EGUs were only evaluated for PM emissions. Tennessee relied 
on CAIR to satisfy BART for SO2 and NOX for 
its EGUs in CAIR, in accordance with 40 CFR 51.308(e)(4). Thus, 
SO2 and NOX were not analyzed.
---------------------------------------------------------------------------

    The remaining eight sources demonstrated that they are exempt from 
being subject to BART by modeling less than a 0.5 deciview visibility 
impact at the affected Class I areas. The two Tennessee EGU sources, 
TVA--Cumberland and TVA--Bull Run, only modeled PM10 
emissions because Tennessee relied on CAIR to satisfy BART for 
SO2 and NOX for its EGUs in CAIR, in accordance 
with 40 CFR 51.308(e)(4). The TVA--Bull Run Fossil Plant demonstrated 
that its PM10 emissions do not contribute to visibility 
impairment in any Class I area. Modeling at the TVA--Cumberland Fossil 
Plant, on the other hand, demonstrated that its PM10 
emissions exceeded the 0.5 deciview contribution threshold and thus, 
required a BART analysis. 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, as explained in section IV of this notice, 
the BART assessments for CAIR EGUs for NOX and 
SO2 and other provisions in this SIP revision are based on 
CAIR, and thus, the Agency proposes today to issue a limited approval 
and a limited disapproval of the State's April 4, 2008, regional haze 
SIP revision.

C. BART Determinations

    Four BART-eligible sources (i.e., Alcoa South Plant, Eastman 
Chemical Company--Tennessee Operations, DuPont Old Hickory, and TVA--
Cumberland Fossil Plant) had modeled visibility impacts of more than 
the 0.5 deciview threshold for BART exemption. These four facilities 
are therefore considered to be subject to BART. Consequently, they each 
submitted to the State permit applications that included their 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. Alcoa
a. Background
    The Alcoa facility, located in Alcoa, Tennessee, is a BART-eligible 
source containing 24 BART-eligible emission units. Potlines 1 and 2 
emit SO2 and PM, and the anode bake furnace emits 
SO2, NOX, and PM. Two of the remaining 21 
material-handling transfer operations are negligible sources of VOC and 
the remaining 19 emit PM only. Each pollutant and its effect on the 
visibility on Class I areas was analyzed by the State. Although 
eventually considered when taken together, for ease of reference, the 
analysis of existing controls for each pollutant is set forth below.
b. Potlines 1 and 2, and Anode Bake Furnace
    (1) PM BART Review. Potlines 1 and 2 and the anode bake furnace are 
already equipped with a sophisticated fluidized reactor emission 
control system followed by fabric filters for PM control. Tennessee 
determined that these controls are BART for PM for these units. Given 
that this high-efficiency control system is superior or equal to other 
feasible control options, no further analysis of PM controls for these 
three units was performed, as allowed by the BART Guidelines in cases 
where the best level of control is already in place.
    (2) SO2 BART Review. For potline SO2 emissions, TDEC 
evaluated eight different SO2 control options as having 
potential application as part of the BART analysis. Of the eight 
control options, TDEC identified two technically feasible options for 
controlling SO2 emissions from the potlines and anode bake 
furnace: adding a wet scrubber to the potline and/or anode bake furnace 
exhausts, and limiting the sulfur content in the coke used to produce 
anodes to three percent. Tennessee determined BART for SO2 
for Potlines 1 and 2, and the anode bake furnace, to be a limit of 
three percent sulfur in the coke used to manufacture anodes. This limit 
will cap potline SO2 emissions below current allowable 
emissions. Use of wet scrubbing technology to reduce potline 
SO2 emissions was rejected as BART due to excessive costs. 
The estimated total cost-effectiveness of wet scrubbing was $7,500 per 
ton of SO2 removed, and capital and total annualized costs 
were estimated to be $200,000,000 and $39,000,000 per year, 
respectively. The potlines were not identified as being a source of 
NOX.

[[Page 33679]]

    (3) NOX BART Review. The potlines were not identified as being a 
source of NOX, however, the company did identify the anode 
bake furnace as a source of NOX. The company also identified 
two potentially applicable NOX emission controls for the 
anode bake furnace: Advanced firing systems and add-on controls. TDEC 
determined that add-on controls were not feasible because of the low 
temperature (less than 450[deg] F) and presence of tar vapor. Add-on 
controls for NOX typically require elevated temperatures (in 
excess of 850[deg] F) and tar vapor would foul a catalyst. Advanced 
firing systems, which reduce NOX formation by using less 
natural gas to operate, were found to be technically feasible for anode 
baking and were evaluated further as part of the BART determination 
analysis.
    TDEC determined that NOX emissions from the anode bake 
furnace could be reduced by installing an advanced firing system, which 
not only reduces total gas usage (by 20 percent), but also reduces 
NOX emissions by 20 percent, or approximately 17 tons per 
year. While the advanced firing system for the anode bake furnace is 
cost neutral (meaning the savings in reduced natural gas consumption 
would offset the cost of the installation of the system), the 
visibility impact analysis predicts only a 0.001 deciview improvement 
in visibility at the nearest Class I area from use of this technology. 
Based on the negligible change in visibility resulting from the 
installation of an advanced firing system, Tennessee concluded that 
this technology does not represent BART for NOX for the 
Alcoa anode bake furnace. Tennessee also determined that the available 
controls are not reasonable and that it was reasonable to find that 
BART for the anode baking furnace at the Alcoa facility located in 
Alcoa, Tennessee was no control for NOX emissions.
c. Support Operations
    The remaining 21 BART-eligible emission units at Alcoa are material 
handling and transfer operations that support the potlines and the 
anode bake furnace. Two of these support operations are negligible 
sources of VOC. TDEC has determined that controlling anthropogenic 
sources of VOC emissions would have little, if any, visibility benefits 
at the Class I areas in or nearby Tennessee, and, thus, as noted in 
section V.C.1 of this action, Tennessee did not further evaluate VOC 
emissions sources for potential controls under BART or reasonable 
progress.
    PM BART Review. Emissions from the remaining 19 support operations 
consist of relatively small amounts of PM that are controlled by fabric 
filter control devices. Fabric filters effectively remove greater than 
99 percent of particulate emissions. Based on a control technology 
review, this type of control represents the best available control for 
the material handling and transfer operations at the Alcoa facility. 
Given that fabric filters represent the best available control for PM, 
and the relatively low level of PM emissions, these emission sources 
were excluded from both visibility modeling and further BART 
engineering analysis, as allowed by the BART Guidelines in cases where 
the best level of control is already in place (70 FR 39163-39164). 
Additionally, based on modeling results provided by Alcoa, visibility 
impacts from individual fabric filters are projected to be less than or 
equal to 0.01 deciview. Therefore, Tennessee determined that BART for 
PM for these 19 support operations is the existing level of control.
d. EPA Assessment
    EPA agrees with Tennessee's analyses and conclusions for the BART 
emission units located at this Alcoa facility. EPA has reviewed the 
Tennessee analyses and concluded 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). Therefore the conclusions reflect a reasonable 
application of EPA's guidance to this source.
2. Eastman Chemical
a. Background
    The Eastman Chemical facility located in Kingsport, Tennessee 
(``Kingsport plant'') is a BART-eligible source with nine emission 
units including: Five tangentially fired 655 million British Thermal 
Units per hour (MMBtu/hr), pulverized coal boilers (boilers 25-29), two 
cracking furnaces, a batch chemical manufacturing operation, and a 500 
MMBtu/hr stoker boiler (boiler 24).
b. Boilers 25-29
    Boilers 25-29 are used for co-production of steam and electricity 
in support of manufacturing operations at the Kingsport plant.
    (1) SO2 BART Review. The average SO2 emission rate for 
calendar year 2005 was 1.4 pounds of SO2 per MMBtu of heat 
input (lb SO2/MMBtu). TDEC identified four technically 
feasible technologies for control of SO2 emissions from 
boilers 25-29: (1) Spray dryer absorbers with fabric filters (SDA-FF); 
(2) sodium hydroxide (caustic) scrubbers; (3) wet-FGD (i.e., limestone 
scrubbing with forced oxidation); and (4) dual alkali systems. TDEC 
concluded that it would be reasonable to install SDA-FF on boilers 25-
29. To meet an emission rate of 0.2 lb/MMBtu or 92 percent 
SO2 control using the current regionally available coal 
supply, Eastman Chemical will also need to convert the existing 
electrostatic precipitator (ESP) to fabric filters. TDEC established as 
BART for SO2 from Boilers 25-29 as the less stringent of the 
following limits: 0.20 lb SO2/MMBtu, or a reduction in 
uncontrolled SO2 emissions by 92 percent. TDEC also 
recognized in its SIP that the SO2 emission limits for BART 
will require the installation of additional PM controls, which will 
further reduce PM, but since the facility is already well controlled 
for PM, the State did not adopt as BART any additional PM limits for 
these boilers. Installing SDA-FF on Boilers 25-29 will reduce the 
three-year average of the maximum 98th percentile impact on visibility, 
as modeled, from 2.38 deciviews to 0.95 deciviews.
    (2) PM and NOX BART Review. In the early 1990s, an ESP was 
installed on each unit to control PM emissions. As discussed in the 
previous subsection V.C.6.C, 2.b.(1), SO2 BART review, additional PM 
controls must be installed on Boilers 25-29 to meet the new BART 
SO2 limits. During 2001-2003, the burners on these boilers 
were retrofitted with a vaned close coupled overfire-air system to 
control NOX emissions. At lower loads, the boiler's mode of 
operation is equivalent to a NOX control strategy known as 
Burner Out of Service, and results in significantly lower 
NOX emissions.
    For NOX, TDEC concluded that while the available 
technologies (running low- NOX burners year-round and 
application of Separated Over-Fire Air (SOFA)) might be considered 
cost-effective on a dollars per ton basis, there are other 
environmental factors that, when weighed against the visibility 
benefits, led the State to conclude that existing seasonal 
NOX controls would be considered BART. The impact of 
reducing the NOX would be to reduce the three-year average 
of the maximum 98th percentile impact on visibility, as modeled for 
this source, from 0.95 deciviews to 0.76 deciviews.
    The environmental factors include: (a) disposal of fly ash rather 
than sales to the concrete industry would increase use of aggregate by 
the cement manufacturing industry and increase waste being sent to 
landfills, and (b) an increase in emissions associated with burning 
coal (i.e., SO2 and PM) due to an increase in fuel use 
caused by a loss

[[Page 33680]]

of boiler efficiency due to higher amounts of unburned carbon in the 
fly ash. The efficiency loss is projected to be around 0.5 percent, 
which is equivalent to about an extra 3,500 tons of coal that must be 
burned each year to generate the same output.
c. Cracking Furnaces
    The two cracking furnaces are used to fire natural gas to provide 
heat to drive a cracking reaction of acetic acid that occurs inside the 
tube assemblies of the furnaces. The furnaces also burn a fuel gas 
which is off-gassed from the manufacturing process. SO2 and 
PM emissions from these units are negligible.
    The NOX emissions potential from these small furnaces is 
low (10.5 tons per year each). Therefore, post-combustion technologies 
such as selective non-catalytic reduction (SNCR) or selective catalytic 
reduction (SCR) would not be cost-effective. Although several different 
combustion control technologies were considered, only the replacement 
of the 24 natural gas burners with new low NOX burners (LNB) 
was considered to be cost-effective. However, because NOX 
emissions are already low using the current technology, the impact on 
visibility from the LNB would be very limited. Additionally, replacing 
the existing burners with LNB would change the natural gas flame 
profile, which would have unknown effects on the heat profile. Changing 
the heat profile could adversely affect the ability of the cracking 
furnaces to provide for the cracking reaction to take place and to 
continue to provide for 98 percent reduction of the total organic 
carbon in the fuel gas. The cracking furnaces also serve as control 
devices for the New Source Performance Standards (NSPS) under 40 CFR 60 
Subpart NNN. CALPUFF model runs show that the visibility impairment 
caused by these emission units for the 98th percentile daily maximum 
impact is 0.01 deciviews at Great Smoky Mountains National Park. For 
these reasons, TDEC concluded that there are no NOX control 
technologies that are both technically feasible and reasonably cost-
effective to reduce visibility in Class I Areas for these furnaces.
d. Batch Chemical Manufacturing
    The batch chemical manufacturing operation has an operating permit 
to emit NOX, SO2, ammonia and PM. The operation 
is a compilation of specialty organic chemical batch manufacturing 
equipment located in five different buildings. Each of these pieces of 
equipment is controlled by fabric filters, water scrubbers, or caustic 
scrubbers.
    SO2 is controlled by caustic scrubbers, which are 
estimated to achieve 98 percent control. PM is controlled to a minimum 
efficiency of 95 percent. NOX has not been emitted by this 
unit in several years. However, if products were to be manufactured 
that emitted NOX, they would be controlled by caustic 
scrubbers and the annual emissions would be limited to 14 tons. Ammonia 
emissions are controlled by water scrubbers which achieve control 
efficiencies from 20-60 percent and are limited to annual emissions of 
22.4 tons. Given these high control efficiencies and the low total 
annual emissions allowed, TDEC concluded further control of 
SO2, NOX, ammonia, and PM would not be reasonable 
for the batch chemical manufacturing operation.
e. Boiler 24
    Boiler 24 burns bituminous coal along with wastewater treatment 
biosludge and liquid chemical wastes. This unit is used for co-
production of steam and electricity in support of manufacturing 
operations at the Kingsport plant as well as the destruction of 
biosludge from Eastman's wastewater treatment facility and waste 
chemicals.
    Boiler 24 is equipped with an ESP for PM, and an overfire air 
system is built into the stoker design for NOX emission 
control. Additionally, because this boiler routinely burns a wastewater 
treatment biosludge that is about 85 percent water, the injection of 
this material cools the flame temperature and reduces NOX by 
approximately 20 percent. No additional NOX control 
technology was considered technically feasible. The most cost-effective 
option for control of SO2 that is technically feasible has a 
cost-effectiveness of about $3,000-$4,000 per ton.
    Eastman Chemical evaluated several SO2 scrubbing options 
for boiler 24. Boiler 24 is in a different building than boilers 25-29. 
Therefore, there is no economy of scale with the lime handling system 
or caustic storage system. Also, there is little available space 
adjacent to Boiler 24. The absorber would have to be either elevated 
above the adjacent rail yard or located some distance away with 
ductwork spanning railroad tracks or a roadway. Similarly, to 
accommodate a new fabric filter, Eastman Chemical's options include 
retrofitting the ESP to a fabric filter, or demolishing the existing 
ESP and building a baghouse in its place. As a result, the most cost-
effective option for control of SO2 that is technically 
feasible has a cost-effectiveness of about $3,000-$4,000 per ton, and 
would reduce the three-year average of the maximum 98th percentile 
impact on visibility by approximately 0.1 deciview. TDEC concluded that 
no additional control of PM, NOX or SO2 for BART 
should be required for Boiler 24.
f. EPA Assessment
    EPA reviewed the TDEC BART determinations summarized above and 
agrees with Tennessee's analyses and conclusions for BART for Eastman 
Chemical, because the analyses were conducted consistent with EPA's 
BART Guidelines and EPA's Air Pollution Control Cost Manual, and 
reflect a reasonable application of EPA's guidance to this source.
3. TVA Cumberland
a. Background
    The TVA Cumberland Fossil Plant has two pulverized-coal-fired steam 
generators that are considered BART-eligible. Units 1 and 2 are 
nominally rated at about 1,325 megawatts each.
b. BART Assessment
    EGU Units 1 and 2 are both equipped with FGD for SO2 
control, SCR systems for controlling NOX, and ESPs to 
control PM emissions. In addition, TVA Cumberland currently uses 
hydrated lime injection on both units to mitigate stack opacity.
    (1) SO2 and NOX BART Review. The two emission units at TVA 
Cumberland are also subject to the EPA CAIR. TVA Cumberland has already 
installed scrubbers and NOX controls on the emission units 
at this facility. As discussed in section V.C., Tennessee has opted to 
rely on CAIR to satisfy BART for SO2 and NOX for 
its EGUs subject to CAIR, as allowed by 40 CFR 51.308(e)(4). Thus, TVA 
Cumberland submitted a BART exemption modeling demonstration for PM 
emissions only.
    (2) PM BART Review. TDEC prepared an engineering analysis to 
determine whether there is a technically and economically feasible 
control scenario that represents BART for PM. The modeling analysis 
demonstrated that approximately 96 percent of the visibility impacts at 
the affected Class I areas can be attributed to condensable 
PM10 emissions (i.e., sulfites (SO3)). Thus, the 
engineering evaluation for TVA Cumberland focuses on control of 
SO3/sulfuric acid (H2SO4) emissions. 
The only option identified as technically feasible for controlling PM 
was to reduce additional SO3 emissions at the Cumberland 
facility with a wet ESP. While application of a wet ESP would reduce 
visibility impacts, TDEC determined that not only would the

[[Page 33681]]

costs associated with retrofitting the facility with a wet ESP be high, 
but that the ESP would also require large volumes of water to operate 
it. TDEC estimated that the total capital investment required to 
install a wet ESP at this facility is approximately $176 million per 
emission unit, with total annual costs of approximately $50.5 million 
per year, and a corresponding cost-effectiveness of over $85,000 per 
ton of PM removed.
    TDEC determined that for the TVA Cumberland Fossil Plant, no 
additional controls for PM will be required. Since the facility is 
currently well controlled for SO2 and PM, additional control 
was removed from consideration during this implementation period based 
on cost and environmental impacts. Consistent with this determination, 
TDEC has adopted into the SIP and as a title V permit condition a limit 
of 0.5 lbs SO2 per MMBtu of heat input which can be met with 
existing controls.
c. EPA Assessment
    EPA agrees with Tennessee's analyses and conclusions for BART for 
the TVA Cumberland facility for PM. EPA notes that while TVA Cumberland 
presently operates a sorbent injection system on each unit to reduce 
SO3/H2SO4 emissions to seven parts per 
million by volume, recent advances in this technology can also allow 
this technology to achieve emission rates comparable to those of a wet 
ESP at much lower cost. EPA expects Tennessee will evaluate this 
improved technology further in the next implementation period as part 
of its reasonable progress assessment. EPA concludes that the analyses 
conducted for the PM emissions are consistent with EPA's BART 
Guidelines and EPA's Air Pollution Control Cost Manual, and the 
conclusions reflect a reasonable application of EPA's guidance to this 
source.
    Prior to the CAIR remand by the, EPA believed the State's 
demonstration that CAIR satisfies BART for SO2 and 
NOX for affected EGUs for the first implementation period to 
be approvable and in accordance with 40 CFR 51.308(e)(4). However, as 
explained in section IV of this notice, the State's demonstration 
regarding CAIR and BART for EGUs, and other provisions in this SIP 
revision, are based on CAIR and thus, the Agency proposes today to 
issue a limited approval and a limited disapproval of the State's 
regional haze SIP revision.
4. DuPont-Old Hickory Plant
a. Background
    The DuPont-Old Hickory Plant operates two BART-eligible units, 
boilers 20 and 24. Boiler 20 is a tangentially-fired coal unit with a 
rated capacity of 445 MMBtu/hr. Boiler 24 is a tangentially fired coal 
unit with a rated capacity of 315 MMBtu/hr. Boiler 24 is presently 
operated only during periods of peak demand, which typically occur in 
the winter, when boiler 20 has insufficient capacity to meet both the 
process and space heating demands of the facility.
b. BART Assessment
    TDEC evaluated nine control strategies for reducing SO2 
and seven strategies for reducing NOX emissions. Based on 
boiler operating data supplied by DuPont Old Hickory, TDEC concluded 
that none of the control strategies were appropriate because the 
strategies did not address the different ways the boilers were operated 
during the year, depending upon the season. The strategies all 
overstated the actual impacts of the facility on regional haze. 
Therefore, instead of requiring the installation of control technology 
on the boilers, TDEC adopted seasonal operating limits in the DuPont 
operating permit. These limits constrain the ability of both boilers to 
operate at the same time, with more stringent limits in the summer when 
visibility impacts are the greatest. With these new limits, the 
facility's impacts on visibility near the Mammoth Cave Class I area are 
less than 0.5 deciview.
    The emission limits adopted by TDEC, and incorporated into DuPont's 
title V operating permit, reduce the combined allowable SO2 
emissions from the boilers 20 and 24 by 20,834 lbs per day (lbs/d) in 
the summer (May through September) to 32,256 lbs/d and by 14,522 lbs/d 
in the winter (October through April) to 38,568 lbs/d. Therefore, the 
facility is reducing allowable NOX emissions from these 
units by 3,978 lbs/d in the summer to 6,120 lbs/d and by 3,330 lbs/d in 
the winter to 6,768 lbs/d. CALPUFF modeling based on these operating 
rates results in a reduction in visibility impact due to the facility's 
contribution which falls below the 0.5 deciview threshold TDEC applied 
for determining whether BART-eligible sources are subject to BART.
c. EPA Assessment
    EPA agrees with Tennessee's analyses and conclusions for BART for 
the DuPont-Old Hickory Plant because the analyses were conducted in a 
manner that is consistent with EPA's BART Guidelines and EPA's Air 
Pollution Control Cost Manual. In addition, the conclusions reflect a 
reasonable application of EPA's guidance to this source.
5. Enforceability of Limits
    The BART determinations for each of the facilities discussed above 
and the resulting BART emission limits were adopted by Tennessee into 
the State's regional haze SIP. TDEC incorporated the BART emission 
limits into state operating permits, and submitted these permits as 
part the State's regional haze SIP. The BART limits will also be added 
to the facilities' title V permits according to the procedures 
established in 40 CFR part 70 or 40 CFR part 71. The BART limits 
adopted in the SIP are as follows: (a) for Alcoa, a limitation of three 
percent sulfur in the petroleum coke used in the facility's electrode 
production operations; (b) for Eastman Chemical, a condition requiring 
compliance with more stringent SO2 limitation on its boilers 
(i.e., boilers 25-29 shall comply with the less stringent of the 
following emission limits: 0.20 lb SO2/MMBtu of heat input 
or reduce uncontrolled SO2 emissions by 92 percent); (c) for 
TVA-Cumberland Fossil Plant, emission limits consistent with existing 
controls (i.e., 0.5 lb SO2/MMBtu of heat input) are denoted 
as BART with no additional control measures; and (d) for DuPont-Old 
Hickory, a limit on the total combined daily emissions for boilers 20 
and 24, based upon seasonal operating limits that reduce allowable 
SO2 emissions from the affected units to 32,256 lbs/d in the 
summer and to 38,568 lbs/d in the winter, and allowable NOX 
emissions from these units to 6,120 lbs/d in the summer and to 6,768 
lbs/d in the winter.
    Tennessee is requiring Eastman Chemical, DuPont-Old Hickory and 
Alcoa to comply with these BART emission limits as follows: ``No later 
than five (5) years after publication in the Federal Register of U.S. 
EPA's approval of Tennessee's Regional Haze State Implementation Plan 
revision * * * '' to allow time for needed operational changes. The 
emission limits for TVA-Cumberland are consistent with existing 
controls and thus, are immediately effective. (For further details of 
the specific BART requirements, see also EPA's TSD to this action, 
section III.D.4, or section 7.5.2 of the Tennessee SIP Narrative.)
7. RPGs
    The RHR at 40 CFR 51.308(d)(1) requires states to establish RPGs 
for each Class I area within the state

[[Page 33682]]

(expressed in deciviews) that provide for reasonable progress towards 
achieving natural visibility. VISTAS modeled visibility improvements 
under existing Federal and state regulations for the period 2004-2018, 
and additional control measures which the VISTAS states planned to 
implement in the first implementation period. At the time of VISTAS 
modeling, some of the other states with sources potentially impacting 
visibility at the Tennessee Class I areas had not yet made final 
control determinations for BART and/or reasonable progress, and thus, 
these controls were not included in the modeling submitted by 
Tennessee. Any controls resulting from those determinations will 
provide additional emissions reductions and resulting visibility 
improvement, which give further assurances that Tennessee will achieve 
its RPGs. This modeling demonstrates that the 2018 base control 
scenario provides for an improvement in visibility better than the 
uniform rate of progress for both of the Tennessee Class I areas for 
the most impaired days over the period of the implementation plan and 
ensures no degradation in visibility for the least impaired days over 
the same period.
    As shown in Table 6 below, Tennessee's RPGs for the 20 percent 
worst days provide greater visibility improvement by 2018 than the 
uniform rate of progress for the State's Class I areas (i.e., 25.79 
deciviews in 2018). Also, the RPGs for the 20 percent best days provide 
greater visibility improvement by 2018 than current best day 
conditions. The modeling supporting the analysis of these RPGs is 
consistent with EPA guidance prior to the CAIR remand. The regional 
haze provisions specify that a state may not adopt a RPG that 
represents less visibility improvement than is expected to result from 
other CAA requirements during the implementation period. 40 CFR 
51.308(d)(1)(vi). Therefore, the CAIR states with Class I areas, like 
Tennessee, took into account emission reductions anticipated from CAIR 
in determining their 2018 RPGs.\17\
---------------------------------------------------------------------------

    \17\ Many of the CAIR states without Class I areas similarly 
relied on CAIR emission reductions within the state to address some 
or all of their contribution to visibility impairment in other 
states' Class I areas, which the impacted Class I area state(s) used 
to set the RPGs for their Class I area(s). Certain surrounding non-
CAIR states also relied on reductions due to CAIR in nearby states 
to develop their regional haze SIP submittals.

                                          Table 6--Tennessee 2018 RPGs
                                                 [In deciviews]
----------------------------------------------------------------------------------------------------------------
                                                                       Uniform
                                        Baseline      2018 RPG--20     rate of       Baseline      2018 RPG--20
                                     visibility--20   percent worst  progress at  visibility--20   percent best
            Class I area              percent worst       days         2018--20    percent best        days
                                          days        (improvement     percent         days        (improvement
                                                     from baseline)   worst days                  from baseline)
----------------------------------------------------------------------------------------------------------------
Great Smoky Mountains National Park          30.28     23.50 (6.78)        25.79          13.58     12.11 (1.47)
Joyce Kilmer-Slickrock Wilderness            30.28     23.50 (6.78)        25.79          13.58     12.11 (1.47)
 Area..............................
----------------------------------------------------------------------------------------------------------------

    The RPGs for the Class I areas in Tennessee are based on modeled 
projections of future conditions that were developed using the best 
available information at the time the analysis was done. These 
projections can be expected to change as additional information 
regarding future conditions becomes available. For example, new sources 
may be built, existing sources may shut down or modify production in 
response to changed economic circumstances, and facilities may change 
their emission characteristics as they install control equipment to 
comply with new rules. It would be both impractical and resource-
intensive to require a state to continually adjust the RPG every time 
an event affecting these future projections changed.
    EPA recognized the problems of a rigid requirement to meet a long-
term goal based on modeled projections of future visibility conditions, 
and addressed the uncertainties associated with RPGs in several ways. 
EPA made clear in the RHR that the RPG is not a mandatory goal. See 64 
FR at 35733. At the same time, EPA established a requirement for a 
midcourse review and, if necessary, correction of the states' regional 
haze plans. See 40 CFR 52.308(g). In particular, the RHR calls for a 
five year progress review after submittal of the initial regional haze 
plan. The purpose of this progress review is to assess the 
effectiveness of emission management strategies in meeting the RPG and 
to provide an assessment of whether current implementation strategies 
are sufficient for the state or affected states to meet their RPGs. If 
a state concludes, based on its assessment, that the RPGs for a Class I 
area will not be met, the RHR requires the state to take appropriate 
action. See 40 CFR 52.308(h). The nature of the appropriate action will 
depend on the basis for the state's conclusion that the current 
strategies are insufficient to meet the RPGs. Tennessee specifically 
committed to follow this process in the long-term strategy portion of 
its submittal.
    EPA anticipates that the Transport Rule will result in similar or 
better improvements in visibility than predicted from CAIR. Because the 
Transport Rule is not final, however, EPA does not know at this time 
how it will affect any individual Class I area and cannot accurately 
model future conditions based on its implementation. By the time 
Tennessee is required to undertake its five year progress review, 
however, it is likely that the impact of the Transport Rule and other 
measures can be meaningfully assessed. If, in particular Class I areas, 
the Transport Rule does not provide similar or greater benefits than 
CAIR and meeting the RPGs at one of its Class I Federal areas is in 
jeopardy, the State will be required to address this circumstance in 
its five year review. Accordingly, EPA proposes to approve Tennessee's 
RPGs for the Great Smoky Mountains National Park and the Joyce Kilmer-
Slickrock Wilderness Area.

D. 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 Federal area includes any integral 
vista associated with that

[[Page 33683]]

area. The FLMs did not identify any integral vistas in Tennessee. In 
addition, neither Class I area in Tennessee is experiencing RAVI, nor 
are any of its sources affected by the RAVI provisions. Thus, the April 
4, 2008, Tennessee regional haze SIP submittal does not explicitly 
address the two requirements regarding coordination of the regional 
haze with the RAVI LTS and monitoring provisions. However, Tennessee 
previously made a commitment to address RAVI should the FLM certify 
visibility impairment from an individual source.\18\ EPA finds that 
this regional haze submittal appropriately supplements and augments 
Tennessee's RAVI visibility provisions to address regional haze by 
updating the monitoring and LTS provisions as summarized below in this 
section.
---------------------------------------------------------------------------

    \18\ Tennessee submitted its visibility SIP revisions addressing 
RAVI on February 9, 1993, and December 19, 1994, which EPA approved 
on July 2, 1997 (62 FR 35681). Tennessee also submitted a SIP 
revision addressing PSD/NSR visibility provisions on January 17, 
1995, that EPA approved on July 18, 1996 (61 FR 37387).
---------------------------------------------------------------------------

    In the April 4, 2008, submittal, TDEC updated its visibility 
monitoring program and developed a LTS to address regional haze. Also 
in this submittal, TDEC affirmed its commitment to complete items 
required in the future under EPA's RHR. Specifically, TDEC 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, TDEC made a commitment to 
submit a report to EPA on progress towards the RPGs for each mandatory 
Class I area located within Tennessee, and in each mandatory Class I 
area located outside Tennessee which may be affected by emissions from 
within Tennessee. 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, Tennessee 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). Also, the Tennessee NSR rules, previously approved in the 
State's SIP, continue to provide a framework for review and 
coordination with the FLMs on new sources which may have an adverse 
impact on visibility in either form (i.e., RAVI and/or regional haze) 
in any Class I Federal area. The Tennessee SIP contains a plan 
addressing the associated monitoring and reporting requirements. See 62 
FR 35681 (July 2, 1997); 40 CFR 52.2239(c)(147). Although EPA's 
approvals of these rules neglected to remove the Federally promulgated 
provisions set forth in 40 CFR 52.2234, EPA corrected this omission in 
a separate rulemaking on April 21, 2010 (75 FR 20783).

E. Monitoring Strategy and Other Implementation Plan Requirements

    The primary monitoring network for regional haze in Tennessee is 
the IMPROVE network. As discussed in section V.B.2. of this notice, 
there is currently one IMPROVE site in Tennessee, which serves as the 
monitoring site for both the Great Smoky Mountains National Park and 
Joyce Kilmer-Slickrock Wilderness Area, both of which lie partly in 
Tennessee and partly in North Carolina.
    IMPROVE monitoring data from 2000-2004 serves as the baseline for 
the regional haze program, and is relied upon in the April 4, 2008, 
regional haze submittal. In the submittal, Tennessee states its 
intention to rely on the IMPROVE network for complying with the 
regional haze monitoring requirement in EPA's RHR for the current and 
future regional haze implementation periods.
    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. 
Tennessee is encouraging VISTAS and the other RPOs to maintain the 
VIEWS or a similar data management system to facilitate analysis of the 
IMPROVE data.
    In addition to the IMPROVE measurements, there is long-term limited 
monitoring by FLMs which provides additional insight into progress 
toward regional haze goals. Such measurements include:
     Web cameras operated by the National Park Service at Look 
Rock, Tennessee at the Great Smoky Mountains National Park
     An integrating nephelometer for continuously measuring 
light scattering, operated by the National Park Service at Look Rock, 
Tennessee
     A Tapered Element Oscillating Microbalance for 
continuously measuring PM2.5 mass concentration, operated by 
the National Park Service at Look Rock, Tennessee.
    In addition, Tennessee and the local air agencies in the State 
operate a comprehensive PM2.5 network of filter-based 
Federal reference method monitors, continuous mass monitors, filter 
based speciated monitors and the continuous speciated monitors.

F. 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.
    TDEC has evaluated the impact of Tennessee sources on Class I areas 
in neighboring states. 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. Because many 
of these states had not yet defined their criteria for identifying 
sources to evaluate for reasonable progress, Tennessee applied its AOI 
methodology to identify sources in the State that have emission units 
with impacts large enough to potentially warrant further evaluation and 
analysis. The State identified 13 emission units in Tennessee with a 
contribution of one percent or more to the visibility impairment at the 
following four Class I areas in three neighboring states: Cohutta 
Wilderness area, Georgia; Mammoth Cave National Park, Kentucky; and 
Linville Gorge and Shining Rock Wilderness areas, North Carolina. Based 
on an evaluation of the four reasonable progress statutory factors, 
Tennessee determined that there are no additional control measures for 
these Tennessee emission units that would be reasonable to implement to 
mitigate visibility impacts in Class I areas in these neighboring 
states. TDEC has consulted with these states regarding its reasonable 
progress control evaluations showing no cost-effective controls 
available for those emission units in Tennessee contributing at least 
one percent to visibility impairment at Class I areas in the states. 
Additionally, TDEC sent letters to the other states in the VISTAS 
region documenting its

[[Page 33684]]

analysis using the State's AOI methodology that no SO2 
emission units in Tennessee contribute at least one percent to the 
visibility impairment at the Class I areas in those states. No adverse 
comments were received from the other VISTAS states. The documentation 
for these formal consultations is provided in Appendix J of Tennessee's 
SIP.
    Regarding the impact of sources outside of the State on Class I 
areas in Tennessee, TDEC sent letters to Alabama, Arkansas, Georgia, 
Kentucky, Missouri, Mississippi, North Carolina, South Carolina, 
Virginia and West Virginia pertaining to emission units within these 
states that the State believes contributed one percent or higher to 
visibility impairment in the Tennessee Class I areas. At that time, 
these neighboring states were still in the process of evaluating BART 
and reasonable progress for their sources. Any controls resulting from 
those determinations will provide additional emissions reductions and 
resulting visibility improvement, which gives further assurances that 
Tennessee will achieve its RPGs. Therefore, to be conservative, 
Tennessee opted not to rely on any additional emission reductions from 
sources located outside the State's boundaries beyond those already 
identified in the State's regional haze SIP submittal and as discussed 
in section V.C.1. (Federal and state controls in place by 2018) of this 
action.
    Tennessee received letters from the Mid-Atlantic/Northeast 
Visibility Union (MANE-VU) RPO States of Maine, New Jersey, New 
Hampshire, and Vermont in the spring of 2007, stating that based on 
MANE-VU's analysis of 2002 emissions data, Tennessee contributed to 
visibility impairment to Class I areas in those states. The MANE-VU 
states identified five TVA EGU stacks \19\ in Tennessee that they would 
like to see controlled to 90 percent efficiency. They also requested a 
control strategy to provide a 28 percent reduction in SO2 
emissions from sources other than EGUs that would be equivalent to 
MANE-VU's proposed low sulfur fuel oil strategy. Working with 
Tennessee, TVA has controlled or is expecting to control three of the 
EGUs, (Kingston 1 & 2 and John Sevier), by the end of 2011. The 
remaining two EGUs, (Gallatin and Johnsonville), have been discussed 
with TVA. TVA has indicated that it will either repower or shut down 
the Johnsonville facility by the next implementation period in 2018 and 
will ultimately control Gallatin if needed to meet its CAIR obligations 
or more stringent controls to meet increasingly stringent NAAQS. TDEC 
evaluated both EGU and non-EGU sources to determine what controls are 
reasonable in this first implementation period. TDEC believes that 
these emissions reductions satisfy MANE-VU's request.
---------------------------------------------------------------------------

    \19\ These five TVA EGUs have been addressed by the April 14, 
2011, CAA settlement discussed in V.C.5.B.1.
---------------------------------------------------------------------------

    EPA finds that Tennessee 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, Tennessee 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. The proposed regional haze 
plan for Tennessee was out for public comment and FLM discussions in 
the November to December 2007 period. Tennessee subsequently modified 
the plan to address comments received on this initial version and 
reissued it for a second round of public participation in the February 
to March 2008 period. The FLMs submitted no significant adverse 
comments regarding the State's regional haze SIP. The FLMs requested 
that Tennessee add more details to support the State's conclusions. 
Additionally, some of the FLM staff had difficulty in navigating 
through the compact disc of electronic support materials. Improvements 
were made to improve navigability. To address the requirement for 
continuing consultation procedures with the FLMs under 40 CFR 
51.308(i)(4), TDEC made a commitment in the SIP to ongoing consultation 
with the FLMs on regional haze issues throughout implementation of its 
plan, including annual discussions. TDEC also affirms in the SIP that 
FLM consultation is required for those sources subject to the State's 
NSR regulations.

G. Periodic SIP Revisions and Five-Year Progress Reports

    As also summarized in section V.D. of this action, consistent with 
40 CFR 51.308(g), TDEC 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 Tennessee regional haze SIP. The report 
will evaluate the progress made towards the RPGs for each mandatory 
Class I area located within Tennessee and in each mandatory Class I 
area located outside Tennessee which may be affected by emissions from 
within Tennessee. Tennessee also offered recommendations for several 
technical improvements that, as funding allows, can support the State's 
next LTS. These recommendations are discussed in detail in the 
Tennessee submittal in Appendix K.
    If another state's regional haze SIP identifies that Tennessee's 
SIP needs to be supplemented or modified, and if, after appropriate 
consultation Tennessee agrees, today's action may be revisited, or 
additional information and/or changes will be addressed in the five-
year progress report SIP revision.

VI. What action is EPA proposing to take?

    EPA is proposing a limited approval and a limited disapproval of a 
revision to the Tennessee SIP submitted by the State of Tennessee on 
April 4, 2008, 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.

VII. Statutory and Executive Order Reviews

A. Executive Order 12866, Regulatory Planning and Review

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

B. Paperwork Reduction Act

    Under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq., OMB must 
approve all ``collections of information'' by EPA. The Act defines 
``collection of information'' as a requirement for answers to * * * 
identical reporting or recordkeeping requirements imposed on ten or 
more persons * * *. 44 U.S.C. 3502(3)(A). The Paperwork Reduction Act 
does not apply to this action.

C. Regulatory Flexibility Act (RFA)

    The RFA generally requires an agency to conduct a regulatory 
flexibility analysis of any rule subject to notice and comment 
rulemaking requirements unless the agency certifies that the rule will 
not have a significant economic impact on a substantial number of small 
entities. Small entities include small businesses, small not-for-profit 
enterprises, and small governmental jurisdictions.
    This rule will not have a significant impact on a substantial 
number of small entities because SIP approvals under section 110 and 
subchapter I, part D of the CAA do not create any new

[[Page 33685]]

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 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

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

List of Subjects in 40 CFR Part 52

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

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

    Dated: May 31, 2011.
A. Stanley Meiburg,
Acting Regional Administrator, Region 4.
[FR Doc. 2011-14292 Filed 6-8-11; 8:45 am]
BILLING CODE 6560-50-P
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