Proposed Rule2025-15748
Air Plan Approval; Tennessee; Second Planning Period Regional Haze Plan
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
August 19, 2025
Issuing agencies
Environmental Protection Agency
Abstract
The Environmental Protection Agency (EPA) is proposing to approve a regional haze State Implementation Plan (SIP) revision submitted by the Tennessee Department of Environmental Conservation (TDEC), dated February 23, 2022, as satisfying the applicable requirements under the Clean Air Act (CAA or Act) and EPA's Regional Haze Rule (RHR) for the program's second planning period. Tennessee's SIP submission addresses the requirement that states must periodically revise their long-term strategies for making reasonable progress toward the national goal of preventing any future, and remedying any existing, anthropogenic impairment of visibility, including regional haze, in mandatory Class I Federal areas. The SIP submission also addresses other applicable requirements for the second planning period of the regional haze program. EPA is proposing this action pursuant to sections 110 and 169A of the Act.
Full Text
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<title>Federal Register, Volume 90 Issue 158 (Tuesday, August 19, 2025)</title>
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[Federal Register Volume 90, Number 158 (Tuesday, August 19, 2025)]
[Proposed Rules]
[Pages 40272-40295]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2025-15748]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R04-OAR-2019-0308; FRL-10404-01-R4]
Air Plan Approval; Tennessee; Second Planning Period Regional
Haze Plan
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The Environmental Protection Agency (EPA) is proposing to
approve a regional haze State Implementation Plan (SIP) revision
submitted by the Tennessee Department of Environmental Conservation
(TDEC), dated February 23, 2022, as satisfying the applicable
requirements under the Clean Air Act (CAA or Act) and EPA's Regional
Haze Rule (RHR) for the program's second planning period. Tennessee's
SIP submission addresses the requirement that states must periodically
revise their long-term strategies for making reasonable progress toward
the national goal of preventing any future, and remedying any existing,
anthropogenic impairment of visibility, including regional haze, in
mandatory Class I Federal areas. The SIP submission also addresses
other applicable requirements for the second planning period of the
regional haze program. EPA is proposing this action pursuant to
sections 110 and 169A of the Act.
DATES: Written comments must be received on or before October 20, 2025.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R04-
OAR-2019-0308, at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. Follow the online
instructions for submitting comments. Once submitted, comments cannot
be edited or removed from <a href="http://Regulations.gov">Regulations.gov</a>. EPA may publish any comment
received to its public docket. Do not submit
[[Page 40273]]
electronically any information you consider to be Confidential Business
Information (CBI) or other information whose disclosure is restricted
by statute. Multimedia submissions (audio, video, etc.) must be
accompanied by a written comment. The written comment is considered the
official comment and should include discussion of all points you wish
to make. EPA will generally not consider comments or comment contents
located outside of the primary submission (i.e., on the web, cloud, or
other file sharing system). For additional submission methods, the full
EPA public comment policy, information about CBI or multimedia
submissions, and general guidance on making effective comments, please
visit <a href="https://www.epa.gov/dockets/commenting-epa-dockets">https://www.epa.gov/dockets/commenting-epa-dockets</a>.
FOR FURTHER INFORMATION CONTACT: Estelle Bae, Air Permits Section, Air
Planning and Implementation Branch, Air and Radiation Division, U.S.
Environmental Protection Agency, Region 4, 61 Forsyth Street SW,
Atlanta, Georgia 30303-8960. Ms. Bae can be reached via telephone at
(404) 562-9143 or electronic mail at <a href="/cdn-cgi/l/email-protection#ddbfbcb8f3b8aea9b8b1b1b89db8adbcf3bab2ab"><span class="__cf_email__" data-cfemail="6c0e0d0942091f18090000092c091c0d420b031a">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Table of Contents
I. What action is EPA proposing?
II. Background and Requirements for Regional Haze Plans
A. Regional Haze Background
B. Roles of Agencies in Addressing Regional Haze
III. Requirements for Regional Haze Plans for the Second Planning
Period
A. Long-Term Strategy (LTS) for Regional Haze
B. Reasonable Progress Goals (RPGs)
C. Monitoring Strategy and Other Implementation Plan
Requirements
D. Requirements for Periodic Reports Describing Progress Towards
the RPGs
E. Requirements for State and Federal Land Manager (FLM)
Coordination
IV. EPA's Evaluation of Tennessee's Regional Haze Submission for the
Second Planning Period
A. Identification of Class I Areas
B. Calculations of Baseline, Current, and Natural Visibility
Conditions; Progress to Date; and the Uniform Rate of Progress (URP)
C. LTS for Regional Haze
D. RPGs
E. Monitoring Strategy and Other Implementation Plan
Requirements
F. Requirements for Periodic Reports Describing Progress Towards
the RPGs
G. Requirements for State and FLM Coordination
V. Other Measures Proposed for Incorporation Into Tennessee's SIP
VI. Incorporation by Reference
VII. Proposed Action
VIII. Statutory and Executive Order Reviews
I. What action is EPA proposing?
On February 23, 2022, TDEC submitted a SIP to address regional haze
for the second planning period (``Haze Plan'' or ``2022
Plan'').<SUP>1 2</SUP> TDEC made the SIP submission to satisfy the
requirements of the CAA's regional haze program pursuant to CAA
sections 169A and 169B and 40 CFR 51.308. On February 9, 2023,
Tennessee also submitted a separate SIP revision to adopt source-
specific SO<INF>2</INF> emission limits and compliance parameters into
the Tennessee SIP for Eastman (``2023 Plan'').\3\ EPA is proposing to
approve Tennessee's Haze Plan as satisfying applicable statutory and
regulatory requirements for the regional haze second planning period.
EPA is also proposing to incorporate by reference into Tennessee's SIP
permit conditions included in the 2023 Plan for Eastman.\4\ EPA is not
proposing to take action to approve or disapprove other portions of the
2023 Plan in this Notice.
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\1\ Tennessee's February 23, 2022, SIP submission, is included
in the docket for this action.
\2\ On December 20, 2024, Tennessee sent EPA a letter requesting
that EPA incorporate certain permit conditions applicable for
Eastman Chemical Company (Eastman) into Tennessee's SIP to support
the State's Haze Plan and to strengthen Tennessee's SIP. This
letter, received December 20, 2024, is included in the docket for
this proposed action.
\3\ Tennessee's February 9, 2023, SIP submission, is included in
the docket for this action.
\4\ Tennessee submitted the 2023 Plan as an SO<INF>2</INF>
attainment demonstration SIP for Sullivan County. On December 20,
2024, Tennessee submitted a letter to EPA stating that Tennessee
supports EPA adopting certain permit conditions from the 2023 Plan
into Tennessee's SIP to support the Haze Plan and to further
strengthen Tennessee's SIP. While EPA is proposing to adopt permit
conditions from the 2023 Plan into Tennessee's SIP to strengthen
Tennessee's SIP, EPA is not proposing to approve, disapprove, or
otherwise take action on the 2023 Plan itself. Whether the 2023 Plan
is approvable under the CAA--including the permit conditions
included with the 2023 Plan--will be the subject of a separate
rulemaking process.
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II. Background and Requirements for Regional Haze Plans
A detailed history and background of the regional haze program is
provided in prior EPA proposal actions.\5\ For additional background on
the 2017 RHR revisions, please refer to Section III. Overview of
Visibility Protection Statutory Authority, Regulation, and
Implementation of ``Protection of Visibility: Amendments to
Requirements for State Plans'' of the 2017 RHR.\6\ The following is an
abbreviated history and background of the regional haze program and
2017 RHR as it applies to the current proposed action.
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\5\ See 90 FR 13516 (March 24, 2025).
\6\ See 82 FR 3078 (January 10, 2017), located at <a href="https://www.federalregister.gov/documents/2017/01/10/2017-00268/protection-of-visibility-amendments-to-requirements-for-State-plans#h-16">https://www.federalregister.gov/documents/2017/01/10/2017-00268/protection-of-visibility-amendments-to-requirements-for-State-plans#h-16</a>.
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A. Regional Haze Background
In the 1977 CAA Amendments, Congress created a program for
protecting visibility in the nation's mandatory Class I Federal areas,
which include certain national parks and wilderness areas.\7\ See CAA
section 169A. 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 which impairment results
from manmade air pollution.'' See CAA section 169A(a)(1). Regional haze
is visibility impairment that is produced by a multitude of
anthropogenic sources and activities which are located across a broad
geographic area and that emit pollutants that impair visibility.
Visibility impairing pollutants include fine and coarse particulate
matter (PM) (e.g., sulfates, nitrates, organic carbon, elemental
carbon, and soil dust) and their precursors (e.g., sulfur dioxide
(SO<INF>2</INF>), nitrogen oxides (NO<INF>X</INF>), and, in some cases,
volatile organic compounds (VOC) and ammonia (NH<INF>3</INF>)). Fine
particle precursors react in the atmosphere to form fine particulate
matter (particles less than or equal to 2.5 micrometers ([micro]m) in
diameter, PM<INF>2.5</INF>), which impairs visibility by scattering and
absorbing light. Visibility impairment reduces the perception of
clarity and color, as well as visible distance.\8\
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\7\ Areas statutorily 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
CAA section 162(a). There are 156 mandatory Class I areas. The list
of areas to which the requirements of the visibility protection
program apply is in 40 CFR part 81, subpart D.
\8\ There are several ways to measure the amount of visibility
impairment, i.e., haze. One such measurement is the deciview, which
is the principal metric defined and used by the RHR. Under many
circumstances, a change in one deciview will be perceived by the
human eye to be the same on both clear and hazy days. The deciview
is unitless. It is proportional to the logarithm of the atmospheric
extinction of light, which is the perceived dimming of light due to
its being scattered and absorbed as it passes through the
atmosphere. Atmospheric light extinction (b<INF>ext</INF>) is a
metric used for expressing visibility and is measured in inverse
megameters (Mm<SUP>-1</SUP>). The formula for the deciview is 10 ln
(b<INF>ext</INF>)/10 Mm<SUP>-1</SUP>). See 40 CFR 51.301.
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To address regional haze visibility impairment, the 1999 RHR
established an iterative planning process that requires both states in
which Class I areas are located and states ``the emissions from which
may reasonably be anticipated to cause or contribute to any impairment
of visibility'' in a Class
[[Page 40274]]
I area to periodically submit SIP revisions to address such impairment.
See CAA section 169A(b)(2); \9\ see also 40 CFR 51.308(b), (f)
(establishing submission dates for iterative regional haze SIP
revisions); 64 FR 35768 (July 1, 1999).
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\9\ The RHR expresses the statutory requirement for states to
submit plans addressing out-of-state Class I areas by providing that
states must address visibility impairment ``in each mandatory Class
I Federal area located outside the State that may be affected by
emissions from within the State.'' See 40 CFR 51.308(d), (f).
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On January 10, 2017, EPA promulgated revisions to the RHR, (82 FR
3078), that apply for the second and subsequent planning periods. The
reasonable progress requirements as revised in the 2017 rulemaking
(referred to here as the 2017 RHR Revisions) are codified at 40 CFR
51.308(f).
B. Roles of Agencies in Addressing Regional Haze
Because the air pollutants and pollution affecting visibility in
Class I areas can be transported over long distances, successful
implementation of the regional haze program requires long-term,
regional coordination among multiple jurisdictions and agencies that
have responsibility for Class I areas and the emissions that impact
visibility in those areas. To address regional haze, states need to
develop strategies in coordination with one another, considering the
effect of emissions from one jurisdiction on the air quality in
another. Five regional planning organizations (RPOs),\10\ which include
representation from state and Tribal governments, EPA, and FLMs, were
developed in the lead-up to the first planning period to address
regional haze. RPOs evaluate technical information to better understand
how emissions from state and Tribal land impact Class I areas across
the country, pursue the development of regional strategies to reduce
emissions of PM and other pollutants leading to regional haze, and help
states meet the consultation requirements of the RHR.
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\10\ RPOs are sometimes also referred to as ``multi-
jurisdictional organizations,'' or MJOs.
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The Southeastern States Air Resource Managers, Inc. (SESARM), one
of the five RPOs described above, is a collaborative effort of state
and local agencies and Tribal governments established to initiate and
coordinate activities associated with the management of regional haze,
visibility, and other air quality issues in the Southeast. SESARM's
coalition to conduct regional haze work is referred to as Visibility
Improvement State and Tribal Association of the Southeast (VISTAS).\11\
The member states, local air agencies, and Tribal governments of VISTAS
are Alabama, Florida, Georgia, Kentucky, Mississippi, North Carolina,
South Carolina, Tennessee, Virginia, and West Virginia; the local air
agencies, represented by the President of Metro 4 or designee; \12\ and
the Tribes located within the VISTAS region, represented by the Eastern
Band of the Cherokee Indians. The Federal partner members of VISTAS are
EPA, the U.S. National Park Service (NPS), the U.S. Fish and Wildlife
Service (FWS), and the U.S. Forest Service (USFS).\13\
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\11\ The technical analyses for the development of the Haze Plan
were conducted by VISTAS under SESARM and they are available at this
website: <a href="https://www.metro4-sesarm.org/content/vistas-regional-haze-program">https://www.metro4-sesarm.org/content/vistas-regional-haze-program</a>.
\12\ Metro 4 is a Tennessee corporation which represents the
local air pollution control agencies in EPA's Region 4 in the
Southeast. See <a href="https://www.metro4-sesarm.org/content/metro-4-about-us">https://www.metro4-sesarm.org/content/metro-4-about-us</a>.
\13\ The NPS, FWS, and USFS are collectively referred to as the
``Federal Land Managers'' or ``FLMs'' throughout this document.
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III. Requirements for Regional Haze Plans for the Second Planning
Period
Under the CAA and EPA's regulations, all 50 states, the District of
Columbia, and the U.S. Virgin Islands are required to submit regional
haze SIPs satisfying the applicable requirements for the second
planning period of the regional haze program by July 31, 2021. Each
state's SIP must contain an LTS for making reasonable progress toward
meeting the national goal of remedying any existing and preventing any
future anthropogenic visibility impairment in Class I areas. See CAA
section 169A(b)(2)(B). To this end, 40 CFR 51.308(f) lays out the
process by which states determine what constitutes their LTSs, with the
order of the requirements in 40 CFR 51.308(f)(1) through (f)(3)
generally mirroring the order of the steps in the reasonable progress
analysis \14\ and (f)(4) through (f)(6) containing additional related
requirements. Broadly speaking, a state first must identify the Class I
areas within the state and determine the Class I areas outside the
state in which visibility may be affected by emissions from the state.
These are the Class I areas that must be addressed in the state's LTS.
See 40 CFR 51.308(f), (f)(2). For each Class I area within its borders,
a state must then calculate the baseline (five-year average period of
2000-2004, current), and natural visibility conditions (i.e.,
visibility conditions without anthropogenic visibility impairment) for
that area, as well as the visibility improvement made to date and the
URP. The URP is the linear rate of progress needed to attain natural
visibility conditions, assuming a starting point of baseline visibility
conditions in 2004 and ending with natural conditions in 2064. This
linear interpolation is used as a tracking metric to help states assess
the amount of progress they are making towards the national visibility
goal over time in each Class I area. See 40 CFR 51.308(f)(1). Each
state having a Class I area and/or emissions that may affect visibility
in a Class I area must then develop an LTS that includes the
enforceable emission limitations, compliance schedules, and other
measures that are necessary to make reasonable progress in such areas.
A reasonable progress determination is based on applying the four
factors in CAA section 169A(g)(1) to sources of visibility impairing
pollutants that the state has selected to assess for controls for the
second planning period.
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\14\ EPA explained in the 2017 RHR Revisions that the Agency was
adopting new regulatory language in 40 CFR 51.308(f) that, unlike
the structure in 51.308(d), ``tracked the actual planning
sequence.'' See 82 FR 3091, (January 10, 2017).
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Additionally, as further explained below, the RHR at 40 CFR
51.3108(f)(2)(iv) separately provides five ``additional factors'' \15\
that states must consider in developing their LTSs. See 40 CFR
51.308(f)(2). A state evaluates potential emission reduction measures
for those selected sources and determines which are necessary to make
reasonable progress. Those measures are then incorporated into the
state's LTS. After a state has developed its LTS, it then establishes
RPGs for each Class I area within its borders by modeling the
visibility impacts of all reasonable progress controls at the end of
the second planning period, i.e., in 2028, as well as the impacts of
other requirements of the CAA. The RPGs include reasonable progress
controls not only for sources in the state in which the Class I area is
located, but also for sources in other states that contribute to
visibility impairment in that area. The RPGs are then compared to the
baseline visibility conditions and the URP to ensure that progress is
being made towards the statutory goal of preventing any future and
remedying any existing anthropogenic visibility impairment in Class I
areas. See 40 CFR 51.308(f)(2) and (3). There are additional
requirements in the rule, including FLM consultation, that apply to all
visibility protection SIPs and SIP revisions. See e.g., 40 CFR
51.308(i).
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\15\ The five ``additional factors'' for consideration in 40 CFR
51.308(f)(2)(iv) are distinct from the four factors listed in CAA
section 169A(g)(1) and 40 CFR 51.308(f)(2)(i) that states must
consider and apply to sources in determining reasonable progress.
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[[Page 40275]]
A. Long-Term Strategy (LTS) for Regional Haze
While states have discretion to choose any source selection
methodology that is reasonable, whatever choices they make should be
reasonably explained. To this end, 40 CFR 51.308(f)(2)(i) requires that
a state's SIP submission include ``a description of the criteria it
used to determine which sources or groups of sources it evaluated.''
The technical basis for source selection, which may include methods for
quantifying potential visibility impacts such as emissions divided by
distance metrics, trajectory analyses, residence time analyses, and/or
photochemical modeling, must also be appropriately documented, as
required by 40 CFR 51.308(f)(2)(iii).
Once a state has selected the set of sources, the next step is to
determine the emissions reduction measures for those sources that are
necessary to make reasonable progress for the second planning
period.\16\ This is accomplished by considering the four factors--``the
costs of compliance, the time necessary for compliance, and the energy
and nonair quality environmental impacts of compliance, and the
remaining useful life of any existing source subject to such
requirements.'' See CAA section 169A(g)(1). EPA has explained that the
four-factor analysis (FFA) is an assessment of potential emission
reduction measures (i.e., control options) for sources; ``use of the
terms `compliance' and `subject to such requirements' in CAA section
169A(g)(1) strongly indicates that Congress intended the relevant
determination to be the requirements with which sources would have to
comply in order to satisfy the CAA's reasonable progress mandate.'' See
82 FR 3091. Thus, for each source a state has selected for an FFA,\17\
it must consider a ``meaningful set'' of technically feasible control
options for reducing emissions of visibility impairing pollutants. Id.
at 3088.
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\16\ The CAA provides that, ``[i]n determining reasonable
progress there shall be taken into consideration'' the four
statutory factors. See CAA section 169A(g)(1). However, in addition
to FFA for selected sources, groups of sources, or source
categories, a state may also consider additional emission reduction
measures for inclusion in its LTS, e.g., from other newly adopted,
on-the-books, or on-the-way rules and measures for sources not
selected for FFA for the second planning period.
\17\ ``Each source'' or ``particular source'' is used here as
shorthand. While a source-specific analysis is one way of applying
the four factors, neither the statute nor the RHR requires states to
evaluate individual sources. Rather, states have ``the flexibility
to conduct four-factor analyses for specific sources, groups of
sources or even entire source categories, depending on state policy
preferences and the specific circumstances of each state.'' See 82
FR 3088.
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EPA has also explained that, in addition to the four statutory
factors, states have flexibility under the CAA and RHR to reasonably
consider visibility benefits as an additional factor alongside the four
statutory factors.\18\ Ultimately, while states have discretion to
reasonably weigh the factors and to determine what level of control is
needed, 40 CFR 51.308(f)(2)(i) provides that a state ``must include in
its implementation plan a description of how the four factors were
taken into consideration in selecting the measure for inclusion in its
long-term strategy.''
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\18\ See, e.g., Responses to Comments on Protection of
Visibility: Amendments to Requirements for State Plans; Proposed
Rule (81 FR 26942, May 4, 2016) (December 2016), Docket Number EPA-
HQ-OAR-2015-0531, U.S. Environmental Protection Agency at 186,
available at <a href="http://www.regulations.gov">www.regulations.gov</a>.
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As explained above, 40 CFR 51.308(f)(2)(i) requires states to
determine the emission reduction measures for sources that are
necessary to make reasonable progress by considering the four factors.
Pursuant to 40 CFR 51.308(f)(2), measures that are necessary to make
reasonable progress toward the national visibility goal must be
included in a state's LTS and in its SIP. If the outcome of an FFA is
that an emissions reduction measure is necessary to make reasonable
progress towards remedying existing or preventing future anthropogenic
visibility impairment, that measure must be included in the SIP.
The characterization of information on each of the factors is also
subject to the documentation requirement in 40 CFR 51.308(f)(2)(iii).
The reasonable progress analysis is a technically complex exercise, but
also a flexible one that provides states with bounded discretion to
design and implement approaches appropriate to their circumstances.
Given this flexibility, 40 CFR 51.308(f)(2)(iii) plays an important
function in requiring a state to document the technical basis for its
decision making so that the public and EPA can comprehend and evaluate
the information and analysis the state relied upon to determine what
emission reduction measures must be in place to make reasonable
progress.
The technical documentation must include the modeling, monitoring,
cost, engineering, and emissions information on which the state relied
to determine the measures necessary to make reasonable progress.
Additionally, the RHR at 40 CFR 51.3108(f)(2)(iv) separately provides
five ``additional factors'' \19\ that states must consider in
developing their LTSs: (1) emission reductions due to ongoing air
pollution control programs, including measures to address reasonably
attributable visibility impairment; (2) measures to reduce the impacts
of construction activities; (3) source retirement and replacement
schedules; (4) basic smoke management practices for prescribed fire
used for agricultural and wildland vegetation management purposes and
smoke management programs; and (5) the anticipated net effect on
visibility due to projected changes in point, area, and mobile source
emissions over the period addressed by the LTS.
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\19\ The five ``additional factors'' for consideration in 40 CFR
51.308(f)(2)(iv) are distinct from the four factors listed in CAA
section 169A(g)(1) and 40 CFR 51.308(f)(2)(i) that states must
consider and apply to sources in determining reasonable progress.
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Because the air pollution that causes regional haze crosses state
boundaries, 40 CFR 51.308(f)(2)(ii) requires a state to consult with
other states that also have emissions that are reasonably anticipated
to contribute to visibility impairment in a given Class I area. If a
state, pursuant to consultation, agrees that certain measures (e.g., a
certain emission limitation) are necessary to make reasonable progress
at a Class I area, it must include those measures in its SIP. See 40
CFR 51.308(f)(2)(ii)(A). Additionally, the RHR requires that states
that contribute to visibility impairment at the same Class I area
consider the emission reduction measures the other contributing states
have identified as being necessary to make reasonable progress for
their own sources. See 40 CFR 51.308(f)(2)(ii)(B). If a state has been
asked to consider or adopt certain emission reduction measures, but
ultimately determines those measures are not necessary to make
reasonable progress, that state must document in its SIP the actions
taken to resolve the disagreement. See 40 CFR 51.308(f)(2)(ii)(C).
Under all circumstances, a state must document in its SIP submission
all substantive consultations with other contributing states. See 40
CFR 51.308(f)(2)(ii)(C).
B. Reasonable Progress Goals (RPGs)
RPGs ``measure the progress that is projected to be achieved by the
control measures states have determined are necessary to make
reasonable progress based on a four-factor analysis.'' See 82 FR 3091.
For the second planning period, the RPGs are set for 2028. RPGs are
not enforceable targets, 40 CFR 51.308(f)(3)(iii). While states are not
legally obligated to achieve the visibility conditions described in
their RPGs, 40
[[Page 40276]]
CFR 51.308(f)(3)(i) requires that ``[t]he long-term strategy and the
reasonable progress goals must provide for an improvement in visibility
for the most impaired days since the baseline period and ensure no
degradation in visibility for the clearest days since the baseline
period.''
RPGs may also serve as a metric for assessing the amount of
progress a state is making toward the national visibility goal. To
support this approach, the RHR requires states with Class I areas to
compare the 2028 RPG for the most impaired days to the corresponding
point on the URP line (representing visibility conditions in 2028 if
visibility were to improve at a linear rate from conditions in the
baseline period of 2000-2004 to natural visibility conditions in 2064).
If the most impaired days RPG in 2028 is above the URP (i.e., if
visibility conditions are improving more slowly than the rate described
by the URP), each state that contributes to visibility impairment in
the Class I area must demonstrate, based on the FFA required under 40
CFR 51.308(f)(2)(i), that no additional emission reduction measures
would be reasonable to include in its LTS. See 40 CFR 51.308(f)(3)(ii).
To this end, 40 CFR 51.308(f)(3)(ii) requires that each state
contributing to visibility impairment in a Class I area that is
projected to improve more slowly than the URP provide ``a robust
demonstration, including documenting the criteria used to determine
which sources or groups [of] sources were evaluated and how the four
factors required by paragraph (f)(2)(i) were taken into consideration
in selecting the measures for inclusion in its long-term strategy.''
C. Monitoring Strategy and Other State Implementation Plan Requirements
40 CFR 51.308(f)(6) requires states to have certain strategies and
elements in place for assessing and reporting on visibility. Individual
requirements under this section apply either to states with Class I
areas within their borders, states with no Class I areas but that are
reasonably anticipated to cause or contribute to visibility impairment
in any Class I area, or both. Compliance with the monitoring strategy
requirement may be met through a state's participation in the
Interagency Monitoring of Protected Visual Environments (IMPROVE)
monitoring network, which is used to measure visibility impairment
caused by air pollution at the 156 Class I areas covered by the
visibility program. See 40 CFR 51.308(f)(6), (f)(6)(i), (f)(6)(iv).
All states' SIPs must provide for procedures by which monitoring
data and other information are used to determine the contribution of
emissions from within the state to regional haze visibility impairment
in affected Class I areas, as well as a statewide inventory documenting
such emissions. See 40 CFR 51.308(f)(6)(ii), (iii), (v). All states'
SIPs must also provide for any other elements, including reporting,
recordkeeping, and other measures, that are necessary for states to
assess and report on visibility. See 40 CFR 51.308(f)(6)(vi).
D. Requirements for Periodic Reports Describing Progress Toward the
RPGs
40 CFR 51.308(f)(5) requires a state's regional haze SIP revision
to address the requirements of paragraphs 40 CFR 51.308(g)(1) through
(5) so that the plan revision due in 2021 will serve also as a progress
report addressing the period since submission of the progress report
for the first planning period. The regional haze progress report
requirement is designed to inform the public and EPA about a state's
implementation of its existing LTS and whether such implementation is
in fact resulting in the expected visibility improvement. See 81 FR
26942, 26950 (May 4, 2016), 82 FR 3119 (January 10, 2017). To this end,
every state's implementation plan revision for the second planning
period is required to assess changes in visibility conditions and
describe the status of implementation of all measures included in the
state's LTS, including Best Available Retrofit Technology (BART) and
reasonable progress emission reduction measures from the first planning
period, and the resulting emissions reductions. See 40 CFR 51.308(g)(1)
and (2).
E. Requirements for State and Federal Land Manager (FLM) Coordination
CAA section 169A(d) requires that before a state holds a public
hearing on a proposed regional haze SIP revision, it must consult with
the appropriate FLM or FLMs; pursuant to that consultation, the state
must include a summary of the FLMs' conclusions and recommendations in
the notice to the public. Consistent with this statutory requirement,
the RHR also requires that states ``provide the [FLM] with an
opportunity for consultation, in person and at a point early enough in
the State's policy analyses of its long-term strategy emission
reduction obligation so that information and recommendations provided
by the [FLM] can meaningfully inform the State's decisions on the long-
term strategy.'' See 40 CFR 51.308(i)(2). For EPA to evaluate whether
FLM consultation meeting the requirements of the RHR has occurred, the
SIP submission should include documentation of the timing and content
of such consultation. The SIP revision submitted to EPA must also
describe how the state addressed any comments provided by the FLMs. See
40 CFR 51.308(i)(3). Finally, a SIP revision 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. See 40 CFR 51.308(i)(4).
IV. EPA's Evaluation of Tennessee's Regional Haze Submission for the
Second Planning Period
On February 23, 2022, TDEC submitted the Haze Plan to address the
State's regional haze obligations for the second planning period, which
runs through 2028, in accordance with CAA section 169A and the RHR at
40 CFR 51.308(f). In addition, on February 9, 2023, Tennessee submitted
the 2023 Plan, which is separate from and not part of Tennessee's
regional haze SIP submittal. On December 20, 2024, Tennessee provided a
letter to EPA requesting that EPA incorporate specific permit
conditions applicable to Eastman from the 2023 Plan into Tennessee's
SIP to support the State's Haze Plan and to strengthen Tennessee's SIP.
EPA is proposing to approve the Haze Plan. EPA is further proposing
to incorporate into Tennessee's SIP specific permit conditions for
Eastman from the 2023 Plan. The following sections contain EPA's
evaluation of Tennessee's Haze Plan with respect to the requirements of
the CAA and RHR for the second planning period of the regional haze
program. Where applicable, permit conditions from the 2023 Plan are
discussed as well. Tennessee has two Class I areas, both of which are
shared with North Carolina: Great Smoky Mountains National Park
(``Great Smoky Mountains''); and Joyce Kilmer-Slickrock National
Wilderness Area (``Joyce Kilmer''). The following sections describe
Tennessee's Haze Plan, including analyses conducted by VISTAS and
Tennessee's determination based on those analyses, Tennessee's
assessment of progress made since the first planning period in reducing
emissions of visibility impairing pollutants, and the visibility
improvement progress at its Class I areas and nearby Class I areas.
This document also contains EPA's evaluation of
[[Page 40277]]
Tennessee's Haze Plan against the requirements of the CAA and RHR for
the second planning period of the regional haze program.
A. Identification of Class I Areas
1. RHR Requirement: Section 169A(b)(2) of the CAA requires each
state in which any Class I area is located or ``the emissions from
which may reasonably be anticipated to cause or contribute to any
impairment of visibility'' in a Class I area to have a plan for making
reasonable progress toward the national visibility goal. The RHR
implements this statutory requirement at 40 CFR 51.308(f), which
provides that each state's plan ``must address regional haze in each
mandatory Class I Federal area located within the State and in each
mandatory Class I Federal area located outside the State that may be
affected by emissions from within the State,'' and 40 CFR 51.308(f)(2),
which requires each state's plan to include an LTS that addresses
regional haze in such Class I areas. To develop a state's LTS, a state
must first determine which Class I areas may be affected by its own
emissions. Out-of-state Class I area visibility impacts on a statewide
basis are discussed in Section IV.A.2 below and impacts on a source-
specific basis are discussed in Section IV.C.2 below.
2. State Assessment: To address CFR 51.308(f), Tennessee identified
Class I areas affected by Tennessee's statewide emissions of the
visibility impairing pollutants and then consulted with states with
Class I areas affected by Tennessee's statewide emissions.
Specifically, Tennessee presented the results of Particulate Matter
Source Apportionment Technology (PSAT) \20\ modeling which VISTAS
conducted to estimate the projected impact of statewide SO<INF>2</INF>
and NO<INF>X</INF> emissions across all emissions sectors in 2028 on
total light extinction for the 20 percent most impaired days in all
Class I areas in the VISTAS modeling domain.\21\ In Table 7-12 of the
Haze Plan, TDEC lists the total sulfate plus nitrate contribution from
all source sectors in Tennessee to total visibility impairment for the
20 percent most impaired days at Class I areas in the VISTAS modeling
domain in Mm<SUP>-1</SUP>. Tennessee's top three highest sulfate plus
nitrate impairment impacts to out-of-state Class I areas are: Great
Smoky Mountains (North Carolina/Tennessee) (1.98 Mm<SUP>-1</SUP>),
Joyce Kilmer (North Carolina/Tennessee) (1.32 Mm<SUP>-1</SUP>), Cohutta
National Wilderness Area (``Cohutta'') (Georgia) (1.25
Mm<SUP>-1</SUP>).\22\
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\20\ PSAT is Particulate Matter Source Apportionment Technology,
which is an option in the photochemical visibility impact modeling
performed by VISTAS that is a methodology to track the fate of both
primary and secondary PM. PSAT allows emissions to be tracked
(``tagged'') for individual facilities as well as various
combinations of sectors and geographic areas (e.g., by state). The
PSAT results provide the modeled contribution of each of the tagged
sources or groups of sources to the total visibility impacts.
\21\ Tennessee did not include primary PM (directly emitted)
data in this analysis because the PSAT analyses performed by VISTAS
tagged statewide emissions of SO<INF>2</INF> and NO<INF>X</INF> and
did not tag primary PM emissions in the analysis after concluding
that emissions of the PM precursors SO<INF>2</INF> and
NO<INF>X</INF>, particularly from point sources, are projected to
have the largest impact on visibility impairment in 2028 and that
SO<INF>2</INF> and NO<INF>X</INF> are the most significant
visibility impairing pollutants from controllable anthropogenic
sources.
\22\ In contrast, Tennessee's sulfate plus nitrate impairment
impacts to the State's Class I areas are: 1.98 Mm<SUP>-1</SUP> and
1.32 Mm<SUP>-1</SUP> for Great Smoky Mountains and Joyce Kilmer,
respectively.
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Based on the VISTAS' Area of Influence (AoI) and PSAT modeling,
TDEC consulted with the VISTAS states (see Sections 10.1 and 10.2 and
Appendix F-1 of the Haze Plan), including Kentucky, Georgia, and North
Carolina. TDEC also consulted with the Mid-Atlantic/Northeast
Visibility Union (MANE-VU) \23\ states (see Section 10.3 and Appendices
F-2 and F-4 of the Haze Plan), as well as Pennsylvania, Missouri,
Indiana, and Ohio (see Appendix F-2 of the Haze Plan).
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\23\ MANE-VU was established in 2001 to assist the Mid-Atlantic
and Northeast states in planning and developing their regional haze
SIP revisions. The MANE-VU states are Connecticut, Delaware, Maine,
Maryland, Massachusetts, New Hampshire, New Jersey, New York,
Pennsylvania, Rhode Island, and Vermont.
---------------------------------------------------------------------------
3. EPA Evaluation: EPA proposes to find that Tennessee adequately
addressed the elements of 40 CFR 51.308(f) regarding identification of
its statewide visibility impacts to Class I areas outside of the State
and consultation with states with Class I areas which may reasonably be
anticipated to cause or contribute to any impairment of visibility due
to Tennessee's emissions. The State's approach of focusing on
SO<INF>2</INF> and NO<INF>X</INF> impacts from Tennessee is reasonable
on the basis that for current visibility conditions evaluated for the
2015-2019 period, ammonium sulfate is the dominant visibility-impairing
pollutant at most of the VISTAS Class I areas, including the Great
Smoky Mountains, followed by organic carbon and ammonium nitrate
(depending on the area).\24\ VISTAS focused on controllable emissions
from point sources and thus, initially considered impacts from sulfates
and nitrates on regional haze at Class I areas affected by VISTAS
states. EPA finds that Tennessee adequately identified Class I areas
outside of Tennessee that may be affected by emissions from within the
State and consulted with affected states because the State analyzed its
statewide sulfate and nitrate contributions to total visibility
impairment at out-of-state Class I areas in Table 7-12 of the Haze
Plan. The State completed consultation with VISTAS via the RPO
processes and, in some cases, on a state-to-state basis and documented
those consultations.\25\
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\24\ See Figures 2-8 and 2-9 of the Haze Plan for the VISTAS
Class I areas. See also Sections IV.C.2.a and IV.C.3.a of this
document.
\25\ See Section IV.C.2.e of this notice for additional detail
regarding interstate consultations.
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B. Calculations of Baseline, Current, and Natural Visibility
Conditions; Progress to Date; and the URP
1. RHR Requirement: 40 CFR 51.308(f)(1) requires states to
determine the following for ``each mandatory Class I Federal area
located within the State'': baseline visibility conditions for the most
impaired and clearest days, natural visibility conditions for the most
impaired and clearest days, progress to date for the most impaired and
clearest days, the differences between current visibility conditions
and natural visibility conditions, and the URP. This section also
provides the option for states to propose adjustments to the URP line
for a Class I area to account for visibility impacts from anthropogenic
sources outside the United States and/or the impacts from wildland
prescribed fires that were conducted for certain, specified objectives.
See 40 CFR 51.308(f)(1)(vi)(B).
2. State Assessment: In the Haze Plan, Tennessee presents the
baseline visibility conditions (2000-2004) in Table 2-3; current
visibility conditions (2014-2018) in Table 2-5,\26\ and natural
visibility conditions in Table 2-2 for the 20 percent clearest days and
20 percent most impaired days in deciviews for VISTAS Class I areas,
including in-state Class I areas, as shown in Table 1 below.\27\
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\26\ The period 2014-2018 represents current visibility
conditions for Tennessee because it is the most recent five-year
period for which visibility monitoring data was available at the
time of SIP development.
\27\ Joyce Kilmer has no IMPROVE monitor. Visibility at Joyce
Kilmer is assumed to be the same as the nearest Class I area monitor
located at Great Smoky Mountains.
[[Page 40278]]
Table 1--Baseline, Current, and Natural Visibility Conditions in Tennessee's Class I Areas in Deciviews (dv)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline 20% Baseline 20% Current 20% Current 20% Natural 20% Natural 20%
Class I area clearest days most impaired clearest days most impaired clearest days most impaired
(dv) days (dv) (dv) days (dv) (dv) days (dv)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Great Smoky Mountains................................... 13.58 29.11 8.35 17.21 4.62 10.05
Joyce Kilmer............................................ 13.58 29.11 8.35 17.21 4.62 10.05
--------------------------------------------------------------------------------------------------------------------------------------------------------
Tennessee also calculated the actual progress made toward natural
visibility conditions since the baseline period (current minus
baseline), and the additional progress needed to reach natural
visibility conditions from current conditions (natural minus current),
in deciviews, as shown in Table 2-6 (for the 20 percent most impaired
days) and Table 2-7 (for the 20 percent clearest days) Class I areas,
as reproduced in part for Tennessee's in-state Class I areas in Table
2, below.
Table 2--Actual Progress for Visibility Conditions in Tennessee's Class I Areas in Deciviews (dv)
----------------------------------------------------------------------------------------------------------------
Current minus Natural minus
baseline for Current minus current for Natural minus
Class I area clearest 20% baseline for most clearest 20% current for most
(dv) impaired 20% (dv) (dv) impaired 20% (dv)
----------------------------------------------------------------------------------------------------------------
Great Smoky Mountains................. -5.23 11.90 3.73 7.16
Joyce Kilmer.......................... -5.23 11.90 3.73 7.16
----------------------------------------------------------------------------------------------------------------
Additionally, Figure 3-1 of Tennessee's Haze Plan provides the URP
on the 20 percent most impaired days for Great Smoky Mountains (which
also represents the URP for Joyce Kilmer). The URP was developed using
EPA guidance \28\ and used data collected from the IMPROVE monitoring
network which is used to measure visibility impairment caused by air
pollution at the 156 Class I areas covered by the visibility program.
All Tennessee Class I areas are projected to be below the 2028 URP
value for the second planning period based on modeling done by VISTAS.
---------------------------------------------------------------------------
\28\ ``Technical Guidance on Tracking Visibility Progress for
the Second Implementation Period of the Regional Haze Program.'' EPA
Office of Air Quality Planning and Standards, Research Triangle Park
(December 20, 2018), available at: <a href="https://www.epa.gov/sites/default/files/2018-12/documents/technical_guidance_tracking_visibility_progress.pdf">https://www.epa.gov/sites/default/files/2018-12/documents/technical_guidance_tracking_visibility_progress.pdf</a> and <a href="https://www.epa.gov/sites/default/files/2020-06/documents/memo_data_for_regional_haze_technical_addendum.pdf">https://www.epa.gov/sites/default/files/2020-06/documents/memo_data_for_regional_haze_technical_addendum.pdf</a>.
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3. EPA Evaluation: EPA is proposing to find that Tennessee's Haze
Plan meets the requirements of 40 CFR 51.308(f)(1) because the State
provided for its two Class I areas: baseline, current, and natural
visibility conditions for the 20 percent clearest days and most
impaired days; progress to date for the 20 percent clearest days and
most impaired days; differences between the current visibility
conditions and natural visibility conditions; and the URP for each
Class I area in Tennessee.
C. LTS for Regional Haze
1. RHR Requirement: Each state having a Class I area within its
borders or emissions that may affect visibility in a Class I area must
develop an LTS for making reasonable progress towards the national
visibility goal. See CAA section 169A(b)(2)(B). After considering the
four statutory factors, all measures that are determined to be
necessary to make reasonable progress must be in the LTS. In developing
its LTS, a state must also consider the five additional factors in 40
CFR 51.308(f)(2)(iv). As part of its reasonable progress
determinations, the state must describe the criteria used to determine
which sources or group of sources were evaluated (i.e., subjected to
FFA) for the second planning period and how the four factors were taken
into consideration in selecting the emission reduction measures for
inclusion in the LTS. See 40 CFR 51.308(f)(2)(iii).
States may rely on technical information developed by the RPOs of
which they are members to select sources for FFAs and to satisfy the
documentation requirements under 40 CFR 51.308(f). Where an RPO has
performed source selection and/or FFAs (or considered the five
additional factors in 40 CFR 51.308(f)(2)(iv)) for its member states,
those states may rely on the RPO's analyses for the purpose of
satisfying the requirements of 40 CFR 51.308(f)(2)(i) so long as the
states have a reasonable basis to do so and all state participants in
the RPO process have approved the technical analyses. See 40 CFR
51.308(f)(2)(iii). States may also satisfy the requirement of 40 CFR
51.308(f)(2)(ii) to engage in interstate consultation with other states
that have emissions that are reasonably anticipated to contribute to
visibility impairment in a given Class I area under the auspices of
intra- and inter-RPO engagement.
The consultation requirements of 40 CFR 51.308(f)(2)(ii) provide
that states must consult with other states that are reasonably
anticipated to contribute to visibility impairment in a Class I area to
develop coordinated emission management strategies containing the
emission reductions measures that are necessary to make reasonable
progress. Sections 51.308(f)(2)(ii)(A) and (B) require states to
consider the emission reduction measures identified by other states as
necessary for reasonable progress and to include agreed upon measures
in their SIPs, respectively. Section 51.308(f)(2)(ii)(C) speaks to what
happens if states cannot agree on what measures are necessary to make
reasonable progress. The documentation requirement of 40 CFR
51.308(f)(2)(iii) provides that states may meet their obligations to
document the technical bases on which they are relying to determine the
emission reductions measures that are necessary to make reasonable
progress through an RPO, as long as the process has been ``approved by
all State participants.''
Section 51.308(f)(2)(iii) also requires that the emissions
information considered to determine the measures that are necessary to
make reasonable progress include information on emissions for the most
recent year for which the state has submitted triennial emissions data
to EPA (or a more recent
[[Page 40279]]
year), with a 12-month exemption period for newly submitted data.
2. State Assessment: To develop Tennessee's LTS, TDEC set criteria
to identify sources to evaluate for potential controls using the four
factors outlined in Section III.A, selected sources based on those
criteria, considered the four factors, provided emissions limits and
supporting conditions for adoption into the regulatory portion of the
SIP, and evaluated the five additional factors at 40 CFR
51.308(f)(2)(iv).
a. Source Selection Criteria: With respect to 40 CFR
51.308(f)(2)(i), Tennessee, through VISTAS, used a two-step source
selection process: (1) AoI analysis, and (2) PSAT \29\ modeling for
sources exceeding an AoI threshold.\30\ Tennessee considered the four
statutory factors for sources that exceeded both the AoI and PSAT
thresholds. Both sulfates and nitrates were considered in the source
selection process. To identify sources having the most impact on
visibility at Class I areas for PSAT modeling, Tennessee used an AoI
threshold of greater than or equal to three percent for sulfate at any
Tennessee Class I area for all sources within the State and three
percent for sulfate <SUP>31 32</SUP> at any Class I area for all
sources outside of the State. The State also ran a similar analysis
using sulfate plus nitrate visibility impairment, which did not result
in any additional sources being selected for PSAT analysis. Sources
that exceeded Tennessee's AoI threshold using point source sulfate
impairment are listed in Table 7-17 of the Haze Plan. Of these sources,
four sources located within Tennessee exceeded the AoI threshold:
Tennessee Valley Authority--Cumberland Fossil Plant (TVA-Cumberland),
Eastman, Tennessee Valley Authority--Kingston Fossil Plant (TVA-
Kingston), and McGhee Tyson Airport. Tennessee removed McGhee Tyson
Airport from the list of sources submitted for PSAT tagging, however,
for the reasons discussed in Section 7.6.3 of the State's submittal,
including the fact that the vast majority of sulfate and nitrate
emissions from this facility are from aircraft that cannot be regulated
under the regional haze program.
---------------------------------------------------------------------------
\29\ PSAT modeling is a type of photochemical modeling which
quantifies individual facility visibility impacts to an area. See
footnote 20.
\30\ The AoI represents the geographical area around a Class I
area in which emissions sources located in the AoI have the
potential to contribute to visibility impairment visibility at that
Class I area. Emissions data from sources in the AoI is then
evaluated to determine which of those sources are most likely
contributing to visibility impairment visibility at that Class I
area. VISTAS used AoI analysis for all point source facilities in
the VISTAS modeling domain to determine the relative visibility
impairment impacts at each Class I area associated with sulfate and
nitrate. The results of the facility-level AoI analyses were then
used to rank and prioritize facilities for further evaluation via
PSAT.
\31\ For identifying sources with the most impact in Class I
areas, other VISTAS states used sulfates and nitrates for evaluating
against the AoI threshold. However, Tennessee only used sulfates in
the AoI selection analysis, stating that the inclusion of
NO<INF>X</INF> in the AoI selection analysis would not have resulted
in any additional facilities tagged for PSAT analysis.
\32\ Tennessee conducted a similar analysis using sulfate plus
nitrate visibility impairment. This analysis indicated that the
inclusion of NO<INF>X</INF> in the AoI selection analysis would not
have resulted in any additional facilities tagged for PSAT analysis.
---------------------------------------------------------------------------
Tennessee, in coordination with the other VISTAS states, then set a
PSAT threshold of greater than or equal to one percent for sulfate and
a separate PSAT threshold of greater than or equal to one percent for
nitrate, by facility.\33\ Sources identified based on the State's PSAT
threshold are listed in Tables 7-40, 7-41 and 7-42 of the Haze Plan. Of
the nine sources identified, seven sources are located in five other
states, and two are located in Tennessee. These nine sources exceeded
the State's sulfate PSAT threshold, and none exceeded the State's
nitrate PSAT threshold, as discussed in Tables 7-23 through 7-29 of the
Haze Plan. Therefore, Tennessee selected two in-state sources, Eastman
and TVA-Cumberland, for an SO<INF>2</INF> emissions control
analysis.\34\ The projected 2028 SO<INF>2</INF> emissions from these
two sources are 6,420 tons per year (tpy) and 8,427 tpy, respectively,
as described in Table 7-43 of the Haze Plan. No sources modeled for
PSAT exceeded the one percent PSAT threshold for nitrates.
---------------------------------------------------------------------------
\33\ In the first planning period, VISTAS states had initially
set a greater than or equal to one percent PSAT threshold by
emission unit when screening sources for reasonable progress
evaluation. For the second planning period, VISTAS states changed
the threshold from greater than or equal to one percent PSAT, by
emission unit, to greater than or equal to one percent PSAT, by
facility. Using a facility basis for emission estimates pulled in
more facilities compared to an emission unit basis, resulting in
more facilities with smaller visibility impacts being examined
compared to the first planning period.
\34\ Eastman is a chemical manufacturing facility. TVA-
Cumberland is currently permitted as a coal-fired steam electric
generating plant.
---------------------------------------------------------------------------
Initially, PSAT results for TVA Kingston Fossil Plant (TVA-
Kingston) also exceeded the State's one percent PSAT threshold for
SO<INF>2</INF>, which would have resulted in that source being selected
for an SO<INF>2</INF> control FFA. However, Tennessee ultimately did
not select TVA-Kingston for an FFA based upon revised emission
projections submitted by TVA. Specifically, in a letter dated February
28, 2020, TVA stated that ``SO<INF>2</INF> mass emissions at [TVA-
Kingston] are projected to be much lower in 2028 (425 tons) than they
have been historically. [TVA-Kingston] is currently TVA's most
expensive coal asset to operate. Based on capacity factors, [TVA-
Kingston] is considered a `Base Dispatchable/Intermediate' asset now,
but is scheduled to transition to a `Peaking Economic/Reliability'
asset beginning in 2026.'' See Haze Plan, Appendix G-1b. TVA thus
projected that 2028 SO<INF>2</INF> emissions from this facility would
be 435 tpy as compared to the 1,866 tpy 2028 projection used in the
initial VISTAS modeling.\35\ Id. Following this letter, TVA's Chief
Operating Officer signed a final record of decision on April 8, 2024,
stating that ``[c]ontinued operation of [TVA-Kingston] beyond 2027
would create operational, and therefore reliability risks in TVA's
system due to the deteriorating condition of the coal units.'' See 89
FR 24557-58 (April 8, 2024). Therefore, in that record of decision, TVA
took final agency action to ``replace the retiring nine [TVA-Kingston]
coal-fired units by the end of 2027.'' Id. at 24559.
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\35\ In this same letter, TVA also projected that TVA-
Cumberland's 2028 emissions would be higher than projected by
VISTAS.
---------------------------------------------------------------------------
TDEC adopted the updated emission projections from TVA's February
28, 2020, letter for use in TDEC's source selection process. Based on
these updated emission projections, TDEC linearly scaled the PSAT
results for TVA-Kingston (as done for other sources in Section 7.6.2 of
the Haze Plan), which resulted in PSAT values of 0.35 percent, 0.40
percent, and 0.41 percent for Cohutta, Great Smoky Mountains, and Joyce
Kilmer, respectively. Because these revised emission projections
resulted in TVA-Kingston no longer exceeding the State's one percent
PSAT source selection threshold, TDEC did not select TVA-Kingston for
an FFA.
The Haze Plan discusses in detail the PM species that contribute
the most to visibility impairment in Tennessee Class I areas and nearby
out-of-state Class I areas. In general, ammonium sulfate continues to
be the dominant visibility impairing pollutant at the Tennessee Class I
areas during the modeling base period of 2009-2013, on nearly all days,
and for the 2014-2018 and 2015-2019 periods.\36\ Although ammonium
sulfate remains the largest contributor to visibility impairment, TDEC
noted that NO<INF>X</INF> contributions to visibility impairment have
become more significant in recent years on some of the 20 percent most
impaired days.
[[Page 40280]]
Figure 2-8 of the Haze Plan shows that for the VISTAS Class I areas,
sulfate continues to be the largest contributor to visibility
impairment on the 20 percent worst visibility days. As noted, nitrate
contributions at VISTAS Class I areas on the 20 percent most impaired
days are generally larger in the more recent 2014-2018 period compared
to the 2009-2013 period (see Figures 2-5 and 2-8 of the Haze Plan).
Within Class I areas affected by emissions from Tennessee, Mammoth Cave
(``MACA1'' IMPROVE site) has the highest observed absolute and relative
nitrate impairment on the 20 percent most impaired days, at over 22
Mm<SUP>-1</SUP> and 30 percent of total visibility impairment.
---------------------------------------------------------------------------
\36\ See Section 2.6.2 (particularly Figures 2-4 through 2-6 for
the 2009-2013 period and Figures 2-7 through 2-9 for the 2014-2018
period).
---------------------------------------------------------------------------
PSAT results indicate that across Tennessee's Class I areas,
sulfate visibility impacts per ton are universally higher than nitrate
visibility impacts per ton. In the Haze Plan, including in Table 10-10,
TDEC notes that the visibility impacts from sulfate as a function of
Mm<SUP>-1</SUP> per ton are universally higher than the same for
nitrate, indicating that reducing SO<INF>2</INF> emissions has a
significantly higher benefit in improving visibility at these Class I
areas compared to reducing NO<INF>X</INF> emissions. Despite some
increase in nitrates, for the reasons discussed, TDEC determined that
SO<INF>2</INF> emissions reductions have a significantly higher benefit
in improving visibility at Tennessee's Class I areas compared to
controlling NO<INF>X</INF> emissions. Therefore, TDEC requested that
facilities perform an FFA only for SO<INF>2</INF> emissions controls
for the second planning period. Because no sources exceeded the State's
PSAT threshold for nitrates and because ammonium sulfate continues to
be the dominant visibility impairing pollutant at Tennessee's Class I
areas (as discussed further below), TDEC focused on evaluating
potential SO<INF>2</INF> controls for Eastman and TVA-Cumberland to
address regional haze in potentially affected Class I areas for this
planning period. TDEC notes in the Haze Plan that it may be appropriate
in future period haze plans to evaluate NO<INF>X</INF> controls
depending on what the future data show.
Figure 7-34 in the Haze Plan shows that projected light extinction
in 2028 from total sulfate on the 20 percent most impaired days is
significantly larger than light extinction from total nitrate for the
Tennessee Class I areas. At Joyce Kilmer, 2028 projected total sulfate
and 2028 total nitrate extinction are approximately 41.3 percent (19
Mm<SUP>-1</SUP>) for sulfate and less than 7.4 percent (less than 3.4
Mm<SUP>-1</SUP>) for nitrate, in comparison to the approximately 46
Mm<SUP>-1</SUP> of 2028 total visibility impairment on the 20 percent
most impaired days).\37\ Also, TDEC states that the majority of model-
predicted 2028 nitrate light extinction on the 20 percent most impaired
days at Great Smoky Mountains and Joyce Kilmer, respectively, is not
caused by NO<INF>X</INF> emissions from EGU and non-EGU point
sources.\38\
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\37\ Percent visibility impairment was calculated using 2028
total visibility impairment on the 20 percent most impaired days at
Great Smoky Mountains (46 Mm<SUP>-1</SUP>) and Joyce Kilmer (45
Mm<SUP>-1</SUP>), based on Table 7-10 of the Haze Plan.
\38\ See Figures 7-33 and 7-34 of the Haze Plan. Figure 7-34
contrasts 2028 total nitrate visibility impairment on the 20 percent
most impaired days at Great Smoky Mountains to the point source
nitrate contributions from EGUs and non-EGUs.
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In Section 10.4.1, TDEC reviewed more recent visibility monitoring
data for the period 2015-2019 from the IMPROVE monitoring network for
Great Smoky Mountains, which also represents Joyce Kilmer. Table 3
below summarizes the percent contribution on the 20 percent most
impaired days at Great Smoky Mountains (also Joyce Kilmer), for certain
PM species (i.e., ammonium sulfate, ammonium nitrate, and organic
carbon) in 2009-2013 versus 2015-2019.\39\
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\39\ The data in Table 3 is derived from Figure 10-1 of the Haze
Plan.
Table 3--Comparison of Five-Year Average (2009-2013 vs. 2015-2019)
Percent (%) Particle Contributions to Light Extinction for 20% Most
Impaired Days at Great Smoky Mountains *
------------------------------------------------------------------------
IMPROVE monitor data for Great Smoky Mountains
-------------------------------------------------------------------------
PM species 2009-2013 2015-2019
------------------------------------------------------------------------
Ammonium Sulfate (In %)........... 76.3 54.4
Ammonium Nitrate (In %)........... 5.2 16.6
Organic Carbon.................... 11.1 17.4
------------------------------------------------------------------------
* Monitoring data for Great Smoky Mountains serves as the IMPROVE data
for Joyce Kilmer.
Figure 7-34 in the 2022 Plan shows that the majority of 2028
predicted nitrate light extinction on the 20 percent most impaired days
at Great Smoky Mountains is not caused by NO<INF>X</INF> emissions from
EGU and non-EGU point sources.\40\ At the Great Smoky Mountains,
projected 2028 total sulfate extinction is greater than 19
Mm<SUP>-1</SUP> and total projected 2028 total nitrate extinction is
less than 3.4 Mm<SUP>-1</SUP>.
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\40\ Figure 7-33 of the Haze Plan provides the 2028 visibility
impairment from nitrate on the 20 percent most impaired days for all
18 Class I Areas in VISTAS. The figure shows the EGU and non-EGU
contributions to total nitrate derived light extinction in 2028.
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b. Consideration of the Four CAA Factors: Tennessee considered each
of the four CAA factors for Eastman and TVA-Cumberland and described
how the four factors (cost of compliance, time necessary for
compliance, energy and non-air quality impacts, and remaining useful
life) were taken into consideration in selecting measures for inclusion
in the State's LTS. The following subsections summarize the State's
evaluation of these facilities, as discussed in Section 7.8 of the Haze
Plan.
i. Eastman: In a letter dated May 15, 2020, TDEC requested that
Eastman confirm that the estimated projected SO<INF>2</INF> emissions
for 2028 are reasonable and to use the 2028 projected emissions as the
baseline emission level for estimating control effectiveness of each
control measure in the cost analyses. The letter also requested that
Eastman conduct an FFA evaluating potential emissions controls the
Boilers 21-24 and Boiler 30.\41\
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\41\ The May 15, 2020, letter is included in Appendix G-2a of
the Haze Plan. In response to this letter, Eastman provided the FFA
for Boilers 21-24 and 30, as well as notified TDEC about the planned
shutdown for Boilers 18-20.
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Regarding the baseline emissions scenario, Appendix G-2b contains a
May 28, 2020, letter from Eastman to TDEC commenting on TDEC's 2028
projected emissions of 6,420 tpy for these affected units at Eastman.
Eastman projects 2028 SO<INF>2</INF> emissions could be as high as the
highest production year in the past ten years, which was calendar year
2011 for a total of 7,510 tons SO<INF>2</INF> from Boilers 18-24, 30,
and 31 combined. In Appendix G-2f, TDEC used an emissions baseline of
7,508 tpy of SO<INF>2</INF> combined for Boilers 18-24, 30,
[[Page 40281]]
and 31.\42\ In addition, Appendix G-2f provides the breakdown baseline
SO<INF>2</INF> emissions for each unit: Boiler 18 (443 tpy); Boiler 19
(443 tpy); Boiler 20 (443 tpy); Boiler 21 (670 tpy); Boiler 22 (670
tpy); Boiler 23 (1,745 tpy); Boiler 24 (1,745 tpy); Boiler 30 (1,136
tpy); and Boiler 31 (213 tpy).
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\42\ See Table 1 on p.2 of Appendix G-2f for the baseline
SO<INF>2</INF> emissions values by emission unit.
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The FFA for Eastman focused on Boilers 21, 22, 23, 24, and 30. For
Boilers 18-20, TDEC determined the permanent shutdown of these three
boilers, no later than December 31, 2028, is necessary for reasonable
progress, as contained in Operating Permit 079592. This permit was
issued by TDEC on February 9, 2022. The final issued permit for the
cessation of Boilers 18-20 is found in Appendix G-2g of the Haze Plan,
and Tennessee's Haze Plan requests that EPA incorporate this permit
into the State's SIP. On June 6, 2025, TDEC informed EPA that Eastman
completed the planned shutdown of Boilers 18, 19, and 20, on February
24, 2025, October 21, 2024, and May 20, 2025, respectively.\43\ The
cessation of operation of Boilers 18-20 before the end of 2028 results
in a projected emissions reduction of 1,329 tpy of SO<INF>2</INF>.
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\43\ Eastman's shutdown documentation form for each of the
Boilers 18, 19, and 20 submitted to TDEC are included in the docket
for this proposed action.
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For Boilers 23 and 24, Eastman previously committed to installing a
permanent dry sorbent injection (DSI) system with an SO<INF>2</INF>
removal efficiency of approximately 60 percent no later than November
1, 2021. Installing DSI systems on both Boilers 23 and 24 is expected
to reduce 2028 projected emissions by 2,094 tpy SO<INF>2</INF>.\44\ The
FFA evaluated replacing the existing electrostatic precipitators (ESPs)
with fabric filters in addition to recently constructed DSI
controls,\45\ which the source states would allow for improved
SO<INF>2</INF> removal efficiency of the DSI. Replacing the existing
ESP with fabric filters would allow for increased DSI sorbent use and
would remove 1,281 tons of SO<INF>2</INF> per year at a cost of $9,004
per ton of SO<INF>2</INF> removed ($/ton), according to Eastman's
calculations, and $8,989 per ton based on TDEC's calculations. TDEC
states that the $9,004/ton of SO<INF>2</INF> removed is 98 percent more
expensive than the highest-cost control selected for Industrial Boilers
that have a heat input greater than 100 MMBtu/hr during the first
planning period, as discussed in Table 4 of Appendix G-2f of the Haze
Plan.\46\ TDEC also notes that the cost of this control for TVA-
Cumberland would be 3.8 times higher than the next highest-cost option
of $2,386/ton in 2020 dollars for spray dryer absorber (SDA) on a
boiler at Tasco Nampa Sugar Company in Idaho.\47\ Eastman's FFA also
noted that the technical feasibility of this option is currently
unknown, and that Eastman estimated the cost-effectiveness assuming
that the replacement of the existing ESP with fabric filters and the
installation of the permanent DSI control is technically feasible.
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\44\ See Table 5 on p.9 of Appendix G-2f for a list of the
SO<INF>2</INF> reductions estimated from the control measures
evaluated by unit.
\45\ Eastman installed temporary DSI controls on Boilers 23 and
24 on June 1, 2019, as an interim measure to address the measured
exceedances of the 1-hr SO<INF>2</INF> NAAQS in 2019. Eastman
completed installation of the permanent DSI controls on these units,
and the units became fully operational in January 2022.
\46\ The highest-cost control option from the VISTAS costs
sheets for SO<INF>2</INF> control costs in the first planning period
was $4,536.72/ton (rounded to $4,537/ton) for the addition of a
caustic scrubber to the now retired unit at Georgia Pacific Big
Island in Virginia.
\47\ Id.
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Regarding Boiler 30, Tennessee notes that the only feasible control
technology Eastman identified to add to the existing current SDA and
ESP to control SO<INF>2</INF> emissions would be the replacement of the
existing ESP with a fabric filter. Eastman calculated a cost
effectiveness of $7,834/ton of SO<INF>2</INF> removed for this control
option, assuming the control efficiency is 70 percent for the SDA/ESP
option. According to the FFA, the replacement of the ESP with a fabric
filter (in conjunction with the SDA) increases the control efficiency
to 92 percent. TDEC compared first planning period regional haze
control costs in 2020 dollars to the Eastman value of $7,834/ton of
SO<INF>2</INF> removed ($7,819/ton according to TDEC's calculations).
TDEC states that the Eastman value of $7,834/ton is 72 to 73 percent
higher than the highest-cost first planning period control option of
$4,537/ton for the addition of a caustic scrubber to the now retired
unit at Georgia Pacific Big Island in Virginia and 3.3 times higher
than the next highest-cost control option of $2,386/ton for SDA on a
boiler at Tasco Nampa Sugar Company in Idaho. Regarding Boiler 31, in
the FFA, Tennessee notes that this boiler is equipped with an SDA
followed by a fabric filter \48\ that achieves a control efficiency of
greater than 92 percent. Therefore, Boiler 31 was considered to have
existing effective controls and was excluded from the State's FFA
analysis.
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\48\ A fabric filter, sometimes referred to as a baghouse,
utilizes fabric filtration to remove particles from the contaminated
gas stream by depositing the particles on fabric material. See
https://www.epa.gov/air-emissions-monitoring-knowledge-base/
monitoring-control-technique-fabric-
filters#:~:text=Description,thepercent20particlespercent20onpercent20
fabricpercent20material.
---------------------------------------------------------------------------
Regarding Boilers 21 and 22, Tennessee notes that units are
currently uncontrolled for SO<INF>2</INF>. Additional controls
evaluated for these units include: installation of DSI; installation of
DSI along with the conversion of the existing ESPs to fabric filters;
installation of SDA/fabric filter; and installation of a wet scrubber.
The option to install an SDA or wet scrubbers and their associated
ancillary equipment were eliminated as they were not technically
feasible. In the Haze Plan, Eastman determined that the only possible
control technology to improve the PM control capability of Boilers 21
and 22 would be the replacement of the existing ESPs with fabric
filters. Eastman calculated a cost effectiveness of $8,725/ton of
SO<INF>2</INF> removed based on an average control efficiency of 90
percent for the DSI plus fabric filters control option for Boilers 21
and 22. If Eastman installs only a DSI and achieves 60 percent control
efficiency for SO<INF>2</INF>, the cost effectiveness becomes $9,070/
ton. TDEC compared these cost effectiveness values identified in
Eastman's FFA with the BART and reasonable progress control
determinations from the first regional haze period valued in 2020
dollars. TDEC noted that $8,725/ton of SO<INF>2</INF> removed is 92
percent higher than the highest option of $4,537/ton for the addition
of a caustic scrubber to the now retired unit at Georgia Pacific Big
Island in Virginia and 3.7 times higher than the next highest-cost
option of $2,386/ton in 2020 dollars for SDA on a boiler at Tasco Nampa
Sugar Company in Idaho.\49\
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\49\ See Table 4 (``VISTAS Cost Effectiveness for Industrial
Boilers >100 MMBtu/hr (SO<INF>2</INF> Controls Only'')) on pp.7-8 of
Appendix G-2f for BART and reasonable progress control
determinations from the first regional haze period valued in 2020
dollars.
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For Boilers 21, 22, 23, 24, and 30, TDEC recalculated the cost of
compliance factor to reflect comments received from EPA and NPS during
the consultation period prior to the public comment period regarding
the interest rate and equipment life. Initially, TDEC used an interest
rate of 8.5 percent in each of the above-described calculations. TDEC
updated the cost calculations to reflect a 3.25 percent interest rate
because this was the current bank prime interest rate at the time of
SIP development.\50\ TDEC also
[[Page 40282]]
lengthened the fabric filter equipment life from 15 to 20 years in
response to EPA and NPS comments. These updated cost calculations using
an interest rate of 3.25 percent and a fabric filter equipment life of
20 years were $5,475/ton (Boiler 30), $6,342 (Boilers 21-22), and
$6,728/ton (Boilers 23-24). TDEC maintained their conclusion that these
cost effectiveness values were not sufficient to justify adopting
controls beyond those originally proposed in Eastman's FFA.\51\
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\50\ The Cost Manual advises using the current bank prime
interest rate as the default or, in the alternative, using a firm-
specific rate that is justified by the source. To identify the
current bank prime interest rate, see ``bank prime loan'' rate in
the table at: <a href="https://www.federalreserve.gov/releases/h15/">https://www.federalreserve.gov/releases/h15/</a>.
\51\ See Table A2 (``Adjustment of Eastman Control Costs Based
on NPS Recommendations (3.25 percent Nominal Interest Rate'') of
Appendix A on p. 21 of Appendix G-2f.
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TDEC also considered the other statutory factors, in addition to
cost, in Appendix G-2f of the Haze Plan. Regarding the time necessary
for compliance, TDEC outlines several factors to consider when
identifying the time necessary for compliance for the control options
evaluated in the Eastman FFA. Upon approval of the Tennessee Haze Plan,
TDEC notes that Eastman would need time for design, permitting,
procurement, control installation, and startup of any new controls
selected. Also, any implementation schedule would need to allow a
unit's planned outage to accommodate Eastman's steam demand. TDEC
estimates that the control strategies could be implemented within five
years of Haze Plan approval or by the 2028 planning milestone (i.e.,
December 31, 2028, which is the end of the second period).
Regarding the remaining useful life of existing sources, TDEC
states that the remaining useful life of the source is presented as 15
years for all control options for the emissions units evaluated. During
Tennessee's review, Tennessee updated Eastman's estimate by increasing
the fabric filter equipment life from 15 years to 20 years and found
that the cost effectiveness did not appreciably change.\52\
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\52\ The adjusted costs from using a 15-year to 20-year fabric
filter equipment life for upgrading the ESP to fabric filters for
Boiler 30 installing a DSI and fabric filter for Boilers 21 and 22
and upgrading ESP to fabric filters for Boilers 23 and 24 are
included in Tables A1 and A2 of Appendix A of Appendix G-2 of the
Haze Plan.
---------------------------------------------------------------------------
No remaining useful life is provided for the shutdown of Boilers
18, 19, and 20 because these boilers were excluded from the FFA due to
the planned shutdowns occurring prior to December 31, 2028, which are
proposed for adoption into the SIP. Eastman submitted the shutdown
documentation to TDEC confirming the shutdown of Boilers 18, 19, and
20, which occurred on February 24, 2025, October 21, 2024, and May 20,
2025, respectively. These three boilers have been replaced with natural
gas boilers, which TDEC permitted in Construction Permit No. 979100
(State effective October 5, 2021).\53\ Based on information received
from Tennessee, the three natural gas boilers have begun operation.
When each natural gas boiler begins operation, the coal-fired boiler it
replaces is required to cease operation per permit condition G18 in
Construction Permit No. 979100.
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\53\ Construction Permit No. 979100 is included in the docket
for this proposed action.
---------------------------------------------------------------------------
Regarding energy and non-air related impacts, the primary energy
and non-air quality environmental impacts associated with these
controls is related to the installation of DSI and fabric filters for
Boilers 21 and 22, replacement of the ESPs on Boilers 23 and 24 with
fabric filters, and replacement of the ESP on Boiler 30 with a fabric
filter. The energy and non-air environmental impacts are the same for
each option. Eastman estimates $50,000 per year of parasitic energy
cost \54\ due to the increased pressure drop associated with a fabric
filter. In addition, for each of the three control options evaluated,
solid waste generation was not identified as a significant non-air
environmental impact. With respect to Boilers 21-22, Eastman's FFA
states that total ash loading associated with this option would be
expected to increase by about 60 percent. With respect to Boilers 23-
24, TDEC's analysis of Eastman's FFA also states that there is likely
to be an increase in ash loading, offset by a decrease in trona usage.
Although total ash loading associated with this option is also expected
to increase by approximately 60 percent, the increased ash capture
would be partially offset by decreased reagent (trona) usage, because
less sorbent is required if a fabric filter is the primary PM control
device. With respect to Boiler 30, the FFA did not identify any changes
in ash loading with this option. Although there would presumably be an
increase in the amount of ash captured for disposal, the increased ash
capture would be offset by decreased reagent (lime) usage because less
sorbent is required if a fabric filter is the primary PM control
device.
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\54\ Parasitic energy refers to the energy used to power the
fans and pumps that transfer heating and cooling from central
heating and cooling plants to conditioned spaces.
---------------------------------------------------------------------------
Based on the FFA for Eastman and the letter from TDEC to EPA dated
December 20, 2024, TDEC is requesting that EPA incorporate into the
regulatory portion of the State's SIP the source-specific
SO<INF>2</INF> emission limits contained within Permit Condition 1 of
Operating Permit Number 079592 (State effective February 9, 2022),
which includes the combined SO<INF>2</INF> limit of 1,396 tons per year
for Boilers 23 and 24 that Tennessee determined is necessary for
reasonable progress for the Eastman facility.<SUP>55 56</SUP> Tennessee
is also requesting that EPA incorporate into the regulatory portion of
the SIP the shutdown of Boilers 18-20 no later than the end of 2028, as
specified in Condition 2 of Permit Number 079592.
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\55\ Additional measures relevant to Eastman's boilers are
contained in the 2023 Plan and can be found in the docket for this
proposed action. These measures are discussed in Section V of this
notice.
\56\ Title V Operating Permit 079592 is included in the docket
for this proposed action.
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ii. TVA-Cumberland: The FFA for TVA-Cumberland focused on Units 1
and 2 at the facility. Regarding baseline emissions used in the FFA
cost calculations, TVA-Cumberland relied upon the three-year average of
actual emissions from 2017-2019 to estimate 2028 SO<INF>2</INF>
emissions for each of the facility's selected emission units. Units 1
and 2 are equipped with a wet FGD system. From 2017 to 2023, Units 1
and 2 had average SO<INF>2</INF> scrubber control efficiencies of 97.4
and 97.0 percent, respectively.\57\
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\57\ See Tennessee TVA-Cumberland scrubber efficiency data file
that is included in the docket for this action titled ``TN_EGU
scrubber efficiency analysis 2017-2023_Propose Rule.
---------------------------------------------------------------------------
In its FFA, TVA identified four potential control measures to
further improve the performance of the existing wet FGD systems,
including: (1) increasing the limestone stoichiometric ratio, (2) using
performance additives, (3) installing wall rings, and (4) redesigning
or replacing spray headers and nozzles. Regarding the baseline
emissions scenario, Appendix G-1b contains a February 28, 2020, letter
from TVA-Cumberland to TDEC commenting on TDEC's 2028 projected
emissions of 8,427 tpy of SO<INF>2</INF> for these affected units at
TVA-Cumberland. TVA-Cumberland projects 2028 SO<INF>2</INF> emissions
for Units 1 and 2 to be 8,633 tpy. TDEC adopted this higher baseline
projected emissions estimate of 8,633 tpy in 2028 for use in this
facility's FFA.
The FFA determined that two control options were technically
feasible: (1) installation of wall rings, which would remove 719 tons
of SO<INF>2</INF> per year at a cost of $2,881/ton of SO<INF>2</INF>
reduced; and (2) the redesign/replacement of spray headers which would
also remove 719 tons of SO<INF>2</INF> per year at a cost of $5,059/ton
of SO<INF>2</INF> reduced. In the Haze Plan, TVA evaluated Units 1 and
2 using an eight percent interest rate and a
[[Page 40283]]
remaining useful life of 10 years.\58\ TDEC revised these cost of
compliance values using a 3.25 percent interest rate, which resulted in
control costs of $2,882/ton (wall rings) and $5,059/ton (spray
headers).\59\ Tennessee indicates in Appendix G-1g of the Haze Plan
that the costs of these control options are above the median cost for
other scrubber upgrades identified by VISTAS in the first planning
period.
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\58\ The 10-year equipment life for the FGD upgrades is based
the remaining useful life of the FGD system TVA-Cumberland which was
installed in 1995 and therefore has been used for approximately 30
years already. EPA's Cost Manual states that FGD systems are
estimated to have an equipment life of 30 years. See <a href="https://www.epa.gov/system/files/other-files/2023-01/wetanddryscrubbers_controlcostmanualspreadsheet_January%202023.xlsm">https://www.epa.gov/system/files/other-files/2023-01/wetanddryscrubbers_controlcostmanualspreadsheet_January%202023.xlsm</a>.
Thus, any FGD upgrades installed are expected to be in use for
approximately 10 years.
\59\ See Table 18 and Appendix A of Appendix G-1g of the Haze
Plan.
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TDEC also included an analysis of the other three factors in
Appendix G-1g of the Haze Plan. Regarding the time necessary for
compliance, TVA estimates the new controls evaluated (wall rings, spray
headers) could be installed within five years of approval of the
Tennessee Haze Plan, which would allow time for design, permitting,
procurement, installation and startup in addition to the time for Units
1 and 2 to be out of service to be retrofitted with controls. TVA notes
that an outage of either Unit 1 or 2 would need to accommodate regional
electricity demands and to be coordinated with maintenance shutdowns of
other regionally affected utilities. If required, TVA estimates that
TVA-Cumberland could comply with a new emissions rate by the end of the
second planning period (December 31, 2028).
Regarding the remaining useful life of existing sources, Units 1
and 2 were installed in 1972 and are near the end of their useful
lives. TVA's projections do not show these units operating past 2035.
As specified in Section 7.2.2 of the Haze Plan, TVA has proposed to
retire one unit as early as 2026 but no later than 2030, and the second
unit as early as 2028 but no later than 2033.\60\ Additionally,
Tennessee notes in its submittal that TVA initiated the National
Environmental Policy Act (NEPA) planning process for these shutdowns at
TVA-Cumberland.\61\
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\60\ Tennessee also considered TVA's notice of intent to prepare
an environmental impact assessment, under NEPA, for the retirement
of TVA-Cumberland. See 86 FR 25933 (May 11, 2021).
\61\ After the time of TDEC's submittal, this process concluded
in a Record of Decision in which TVA concluded that it would shut
down these units. See 88 FR 3767 (January 20, 2023).
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Nonetheless, TDEC did not rely on the projected shutdown of Units 1
and 2 to shorten the remaining useful life factor in the FFA. Instead,
TDEC determined that a remaining useful life of less than ten years
following the installation of either control option is appropriate
because EPA's Cost Control Manual specifies a 30-year lifespan for the
scrubbers and the scrubbers were installed in 1995.
The energy and non-air quality environmental impacts of compliance
for the wall ring installations and redesign/replacement of spray
headers and nozzles evaluated for Units 1 and 2 are the associated
pressure drop increase of 0.5 and 0.1 inches of water at full load,
respectively. These impacts were included in the operating cost
estimate. In addition, both control options increase the annual costs
associated with maintenance, repair, and replacement for the flue gas
duct work. TDEC included these considerations in the cost analyses for
these control options.
Based on TVA-Cumberland's FFA, TDEC determined that no measures are
necessary for reasonable progress for this planning period and that no
measures need to be adopted into regulatory portion of the SIP for this
planning period. This demonstration was made based upon consideration
of the following: (1) the source's past implementation of its existing
measures and its historical emission rate, (2) the source's projected
emissions and emission rate, and (3) any enforceable emissions limits
or other requirements related to the source's existing measures.
With respect to the first factor, TDEC evaluated SO<INF>2</INF>
emissions and emissions rates and heat input from 1999-2020 for Units 1
and 2 to show trends over time. Figures 1 and 2 and Table 1 of Appendix
B within Appendix G-1g show that the emission rates at Units 1 and 2
have declined by about 25 percent since the year 2000 and annual
emissions have decreased by about 64 percent due to declining heat
input. From 2016 to 2020, the SO<INF>2</INF> emission rate for Boilers
1 and 2 at TVA-Cumberland ranged from 0.130 lb/MMBtu to 0.151 lb/MMBtu.
With respect to the second factor, TDEC considered projected
emissions and emission rates for Units 1 and 2 and concluded that the
emission rates for these units will not increase in the future. TVA
projected 8,633 tons of SO<INF>2</INF> in 2028 compared to 7,847 tons
of SO<INF>2</INF> for 2016-2019. TDEC also provided documentation of
historical SO<INF>2</INF> emission rates for TVA-Cumberland Units 1 and
2 showing consistency of SO<INF>2</INF> emissions.
With respect to the third factor, TDEC summarized the relevant
enforceable emissions limits and other related considerations. TVA-
Cumberland's title V permit No. 577855 Condition E3-18 \62\ currently
includes three allowable emission rates for SO<INF>2</INF>: (a)
Tennessee's SO<INF>2</INF> SIP limit (5.0 lbs/MMBtu, 24-hour average),
(b) the BART limit established in 2007 (0.50 lb/MMBtu, 30-day rolling
average), and (c) the Mercury and Air Toxics Standards (MATS) limit
(0.20 lb/MMBtu, 30-day rolling average). TDEC states that because the
SIP limit and BART limit are substantially higher than TVA's MATS
limit, they are not germane to reasonable progress in the second
planning period. Thus, Tennessee believes that Cumberland's existing
MATS limit is representative of the application of existing current
measures Units 1 and 2.
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\62\ Title V Operating Permit No. 577855 is included in the
docket for this proposed action.
---------------------------------------------------------------------------
c. Documentation of Technical Basis: With respect to emissions
information documentation pursuant to 40 CFR 51.308(f)(2)(iii), Section
4 of the Haze Plan explains the State's use of emissions inventories to
develop the plan with additional documentation provided in Appendix B.
Tennessee, through VISTAS, developed a 2011 statewide base year
emissions inventory which was used to project emissions out to 2028,
the end of the second planning period (see Table 4-2 of the Haze Plan).
TDEC also evaluated emissions data from 2017, the year of the most
recent triennial emissions data available at the time of the
development of the Haze Plan, and compared it to 2018, 2019, and 2028
projected emissions, that were used in the modeling.\63\ TDEC also
provided annual anthropogenic PM<INF>2.5,</INF> NO<INF>X</INF>, and
SO<INF>2</INF> emissions data from the 2014 and 2017 National Emissions
Inventory (NEI) years for Tennessee in Tables 13-10, 13-11, and 13-12,
respectively, of the Haze Plan. In Table 13-13, TDEC evaluated annual
SO<INF>2</INF> and NO<INF>X</INF> emissions from Tennessee's power
plants for the period 2014-2019. The 2028 emissions projections were
used to develop the 2028 RPGs for Tennessee's Class I areas. The 2011-
2019 statewide emissions inventories and 2028 emissions projections
were relied upon to satisfy 40 CFR 51.308(f)(6)(v).
---------------------------------------------------------------------------
\63\ A comparison of emissions between 2017, 2018, 2019, and
2028 emissions data is included in the following tables and figures
in the Haze Plan: Table 7-43 (SO<INF>2</INF>) and 7-44
(NO<INF>X</INF>) for facilities in Tennessee; Tables 13-10
(PM<INF>2.5</INF>), 13-11 (NO<INF>X</INF>), 13-12 (SO<INF>2</INF>),
13-13 (SO<INF>2</INF> emissions from Tennessee EGU for CAMD 2014-
2019); Figures 13-4 (Tennessee CAMD Emissions and Heat Input for
2014-2019) and 13-5 VISTAS CAMD Emissions and Heat Input for 2014-
2019.
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[[Page 40284]]
With respect to modeling information documentation pursuant to 40
CFR 51.308(f)(2)(iii), Sections 5 and 6 of the Haze Plan describe the
modeling methods used to develop the plan with additional documentation
provided in Appendix E and results of the RPG modeling in Section 8 of
the plan. Appendix D contains AoI analysis documentation, and Appendix
E contains PSAT analysis documentation. VISTAS used the Comprehensive
Air Quality Model with Extensions (CAMx) photochemical model to perform
visibility modeling for 2028, the end of the second planning period.
The VISTAS regional haze modeling used the annual calendar year 2011
modeling period.
With respect to cost and engineering information documentation
pursuant to 40 CFR 51.308(f)(2)(iii), Section 7.8 of the Haze Plan
details the State's analysis of proposed FFAs for Eastman and TVA-
Cumberland located in Appendix G which evaluated the four factors,
including the cost of compliance factor, and provided detailed cost
calculations for potential new control measures assessed as part of the
engineering analyses.
With respect to monitoring information documentation pursuant to 40
CFR 51.308(f)(2)(iii), the State assessed baseline (2000-2004), current
(2014-2018), and natural visibility conditions for Tennessee's Class I
areas in Section 2 of the Tennessee's Haze Plan with supporting
information located in Appendix C. In particular, Table 2-2 provides
natural visibility conditions for the VISTAS Class I areas, including
Tennessee's areas. Table 2-3 provides 2000-2004 visibility conditions
for Tennessee's Class I areas, Table 2-4 provides 2009-2013 visibility
conditions, and Table 2-5 provides 2014-2018 visibility conditions for
all VISTAS Class I areas, including Tennessee's Class I areas.
d. Assessment of Five Additional Factors in 40 CFR
51.308(f)(2)(iv): With respect to 40 CFR 51.308(f)(2)(iv), Tennessee
considered each of the five additional factors in developing the
State's LTS and evaluated their relevancy for the second planning
period. See Haze Plan, Section 7.9. With respect to 40 CFR
51.308(f)(2)(iv)(A), Tennessee referenced the State's emissions
inventory development for the base year of 2011 as projected out to
2028 for the requirement to assess emission reductions due to ongoing
air pollution control programs, including measures to address
reasonably attributable visibility impairment (RAVI). With respect to
40 CFR 51.308(f)(2)(iv)(B), Tennessee summarized the State's existing
regulations that mitigate the impacts of construction activities by
Tennessee Compilation of Rules & Regulations (hereinafter, ``Rule'')
1200-3-8-.03, which requires additional control measures on source
operating permits to control fugitive dust emissions generated within
plant boundaries.\64\ TDEC notes that benefits from this rule have not
been included in the VISTAS modeling runs. TDEC also notes that fine
soils were a relatively minor contributor to visibility impairment at
the Class I areas in Tennessee during the baseline period of 2000-2004
and that no VISTAS Class I areas experienced significant visibility
impairment from soils during this timeframe. TDEC references data in
its Haze Plan that fine soils continue to be only a minor contributor
to visibility at the Class I areas in Tennessee during the most current
period of monitoring data (2014-2018) and that no VISTAS Class I areas
experienced significant visibility impairment from soils during the
2014-2018 timeframe.
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\64\ See <a href="https://publications.tnsosfiles.com/rules/1200/1200-03/1200-03-08.20180904.pdf">https://publications.tnsosfiles.com/rules/1200/1200-03/1200-03-08.20180904.pdf</a>. The citation of Rule 1200-3-8-.03, which is
also available in the docket, is for reference purposes only and is
not proposed for adoption into the regulatory portion of the
Tennessee SIP.
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With respect to 40 CFR 51.308(f)(2)(iv)(C), Tennessee addressed
source retirement and replacement schedules by summarizing existing and
planned source retirements and describing existing and planned source
retirements accounted for in the 2028 projected emissions in Section
7.2.2, Section 13.3.1, and Section 13.3.2 of the Haze Plan. Section 7.2
generally discusses existing and planned emissions control programs
which reduce emissions of visibility impairing pollutants between the
base year 2011 and the future projection year of 2028.
With respect to 40 CFR 51.308(f)(2)(iv)(D), Tennessee referenced
the State's basic smoke management practices, as detailed in Section
7.9.1 of the Haze Plan, for prescribed fire used for agricultural and
wildland vegetation management purposes and smoke management programs.
In 2012, the State of Tennessee passed the Tennessee Prescribed Burning
Act, which requires a written prescription be prepared and followed by
a certified prescribed burn manager for each prescribed burn. The
Tennessee Division of Forestry within the Tennessee Department of
Agriculture has promulgated regulations (in Rule 0080-07-06) for
certification of prescribed burn managers and guidelines for a
prescribed burn prescription. TDEC has promulgated regulations (in Rule
1200-03-04) that lists the specific circumstances in which open burning
is permissible. Among other things, the regulation prohibits the burn
site from being within one-half mile of a national reservation,
national or state park, wildlife area, national or state forest. On
November 24, 2021, the State of Tennessee, Department of Environment
and Conservation, Divisions of Air Pollution Control, State Park
Operations, and Natural Areas and the State of Tennessee, Department of
Agriculture, Division of Forestry entered into a Memorandum of
Understanding (MOU) which states that all parties will follow Basic
Smoke Management Practices (BSMP) when utilizing prescribed
burning.\65\ TDEC notes that since significant fire impacts are
infrequent at Tennessee Class I areas, these management practices are
adequate visibility protection for this SIP submittal period.
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\65\ For purposes of the MOU, BSMP are defined as those
specified by Table 1 to 40 CFR 50.14.
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With respect to 40 CFR 51.308(f)(2)(iv)(E), Tennessee assessed the
anticipated net effect on visibility due to projected changes in point,
area, and mobile source emissions over the period addressed by the LTS
in development of the RPGs for the Tennessee Class I areas in Section 8
of the Haze Plan. Section 7.2 identifies control measures included in
the VISTAS 2028 inventory and 2028 RPGs and Section 7.2.2 includes
source retirements and replacements for Tennessee sources. Section 8.2
summarizes controls that are not accounted for in the 2028 emissions
inventory or 2028 RPGs, including the Eastman controls and shutdowns
discussed above; out-of-state FFAs, which includes the permanent
shutdown of the Zimmer Power Station in Ohio that will result in the
reduction of 22,134 tpy of SO<INF>2</INF> emissions; and the April 30,
2021, Cross-State Air Pollution Rule (CSAPR) Update, which will reduce
NO<INF>X</INF> emissions at power plants in the 12 subject states
during the ozone season.\66\
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\66\ Starting in the 2021 ozone season, the CSAPR Update Rule
requires additional emissions reductions of NO<INF>X</INF> from
power plants in 12 states. EPA estimates that the Revised CSAPR
Update will reduce NO<INF>X</INF> emissions from power plants in 12
states in the eastern United States by 17,000 tons in 2021 compared
to projections without the rule. See <a href="https://www.epa.gov/csapr/revised-cross-state-air-pollution-rule-update">https://www.epa.gov/csapr/revised-cross-state-air-pollution-rule-update</a>.
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e. Interstate Consultation: Tennessee consulted with other states,
as described below, and RPOs that identified Tennessee sources as
impacting those states' (or states within the RPOs') Class I areas, and
it consulted with the five states with one or more sources
[[Page 40285]]
exceeding Tennessee's PSAT threshold at one or more of Tennessee's
Class I areas.
i. State/RPOs Requesting Consultation with Tennessee: Section
10.1.2 and Appendix F-1 of the Haze Plan documents other states'
consultations with Tennessee during the development of those states'
LTSs regarding impacts from Tennessee's emissions sources on Class I
areas outside of the State. Tennessee consulted with each VISTAS state
during the development of its LTS. In addition, Tennessee received
letters from Missouri, Georgia, and North Carolina requesting a
reasonable progress analysis for certain facilities in Tennessee.
Specifically, with respect to the effect on Mingo Wilderness Area, a
Class I area in Missouri, Missouri requested a reasonable progress
analysis for TVA-Cumberland. With respect to the effect on Cohutta, a
Class I area in Georgia, Georgia requested a reasonable progress
analysis for Eastman. With respect to the effect on Linville Gorge
Wilderness Area (Linville Gorge) and Shining Rock Wilderness Area
(Shining Rock), Class I areas in North Carolina, North Carolina
requested a reasonable progress analysis for TVA-Cumberland. With
respect to the effect on Great Smoky Mountains, Joyce Kilmer, Linville
Gorge, and Shining Rock, North Carolina also requested a reasonable
progress analysis for Eastman. Additionally on April 12, 2021, TDEC and
Alabama held a consultation call to discuss TVA-Cumberland, which had a
1.56 percent sulfate impairment impact in 2028 on Sipsey Wilderness
Area. As discussed in Section 10.2 of the Haze Plan, VISTAS held a
webinar on April 21, 2020, to present to the RPOs and their member
states the VISTAS modeling analysis and results to make them aware of
the impacts on Class I areas in their states. As discussed in Section
7.6.4 of the Haze Plan, Tennessee selected TVA-Cumberland and Eastman
for reasonable progress analysis.
ii. Tennessee's Requests for Consultation with Other States:
Regarding Tennessee's sources' impacts on MANE-VU states, MANE-VU
developed a set of emissions reduction measures identified as being
necessary to make reasonable progress in the five MANE-VU Class I
areas. This strategy consists of six Asks for states within MANE-VU and
five Asks for states outside the region that were found to impact
visibility at Class I areas within MANE-VU. MANE-VU refers to each of
the components of its overall strategy as an ``Ask'' of its member
states.\67\
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\67\ The MANE-VU Ask to states within MANE-VU is available in
the docket and at: <a href="https://otcair.org/manevu/Upload/Publication/Formal%20Actions/MANE-VU%20Intra-Regional%20Ask%20Final%208-25-2017.pdf">https://otcair.org/manevu/Upload/Publication/Formal%20Actions/MANE-VU%20Intra-Regional%20Ask%20Final%208-25-2017.pdf</a>.
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The five Asks for identified states outside the region are
summarized as follows. Ask 1 is to ensure the most effective use of
control technologies on a year-round basis for EGUs with a nameplate
capacity larger than or equal to 25 megawatts with already installed
NO<INF>X</INF> and/or SO<INF>2</INF> controls or obtain equivalent
alternative emission reductions. Ask 2 is to perform an FFA for
emission sources identified in other states, as modeled by MANE-VU,
that have the potential for 3.0 Mm<SUP>-1</SUP> or greater visibility
impacts at any MANE-VU Class I area. Ask 3 recommends identified states
pursue an ultra-low sulfur fuel (ULSF) oil standard as expeditiously as
possible and before 2028, depending on supply availability, as
specified in the Ask.\68\ Ask 4 recommends that identified states
pursue updating permits, enforceable agreements, and/or rules to lock-
in lower emission rates for SO<INF>2</INF>, NO<INF>X</INF> and PM at
EGUs and other large point emission sources larger than 250 MMBtu per
hour heat input that have switched operations to lower emitting
fuels.\69\ Ask 5 recommends each identified state to consider and
report in the SIP measures or programs to: (a) decrease energy demand
through the use of energy efficiency and (b) increase the use within
their state of combined heat and power and other clean distributed
generation technologies including fuel cells, wind, and solar. In
Section 10 and Appendices F-4 and F-4a to F-4f of the Haze Plan,
Tennessee documents its consultation with MANE-VU.
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\68\ The ULSF standards MANE-VU recommended are as follows: (a)
distillate oil to 0.0015 percent sulfur by weight; (b) #4 residual
oil to 0.5 percent sulfur by weight; (c) #6 residual oil to 0.5
percent sulfur by weight.
\69\ Ask 4 states that the permit, enforcement agreement, and/or
rule can allow for suspension of the lower emission rate during
natural gas curtailment.
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In a letter dated August 25, 2017, MANE-VU requested consultation
with Tennessee on the basis that Tennessee exceeds the 3.0
Mm<SUP>-1</SUP> visibility impact threshold for at least one Class I
area in the MANE-VU region. In response to MANE-VU's evaluation of TVA-
Cumberland, TVA-Gallatin, TVA-John Sevier, TVA-Johnsonville, TVA-
Kingston, Cargill Corn Milling, PCA, and Eastman in Tennessee,
Tennessee provided additional emission data to MANE-VU on December 22,
2017. In addition, Tennessee provided information regarding TVA's 2011
court settlement which resulted in shutdowns, new controls, and a
switch from coal to natural gas at certain facilities. In addition,
Tennessee also specified that Cargill Corn Milling facility has
switched from coal to natural gas and is essentially shut down.
On January 27, 2018, VISTAS submitted a letter to MANE-VU with
concerns regarding MANE-VU's assessment of visibility impairment at
MANE-VU Class I areas. The viewpoints are reflected in the letter from
VISTAS to MANE-VU. In the letter, VISTAS noted several disagreements
with MANE-VU's analysis including:
<bullet> MANE-VU used emissions (Q) divided by distance (d), i.e.,
Q/d, to estimate visibility impacts. TDEC disagrees with use of Q/d in
this case because this screening methodology provides conservatively
high estimates of potential visibility impacts by not accounting for
secondary PM, wind direction, or residence time. TDEC claims that MANE-
VU did not provide documentation of how it prepared the 2015 emissions
inventory relied upon.
<bullet> The modeled back trajectories included states with at
least one trajectory originating from the upwind state yet the
documentation does not identify the days in which the trajectories
originated from Tennessee. TDEC believes for distant sources, a
trajectory threshold should be much higher to determine significant
contribution to visibility.
<bullet> MANE-VU used Eta Data Assimilation System (EDAS). TDEC
stated that the North American Mesoscale Forecast System (NAM) model is
more widely used by other agencies and EPA and TDEC believes NAM
provides a more detailed meteorological grid than EDAS.
<bullet> MANE-VU did not explain the technical basis for the
visibility impact threshold that was used to determine downwind
contributing states like Tennessee.
On January 13, 2021, Tennessee sent a letter to MANE-VU with some
preliminary responses to the August 25, 2017, Ask. In the letter,
Tennessee also noted that the MANE-VU methodologies resulted in
inaccurate conclusions that emissions from Tennessee are contributing
to visibility impairment in MANE-VU Class I areas. In addition, in the
letter, Tennessee also notes that Tennessee believes that 2028 is the
appropriate year to evaluate state contributions to visibility
impairment in Class I areas, instead of 2015 or 2011. Tennessee also
submitted its modeled
[[Page 40286]]
combined impact of sulfate and nitrate on visibility impairment for
each of the MANE-VU Class I areas in 2028. The data shows that
Tennessee's 2028 contribution is at or below 0.24 percent for the 20
percent most impaired days and at or below 0.03 percent for the 20
percent clearest data for all of the MANE-VU Class I areas, well below
the two percent contribution threshold. In addition, Tennessee
emphasizes that the use of photochemical and source apportionment
models such as CAMx/PSAT provide more accurate estimates of statewide
contributions to visibility impairment in Class I areas than the
methodologies used by MANE-VU to identify contributing states. Thus,
Tennessee states that the State will not be taking the measures
outlined in the Inter-RPO Ask.
MANE-VU responded to Tennessee's January 13, 2021, letter on
February 17, 2021. In the letter, MANE-VU stated that MANE-VU used a
weight of evidence approach in its analysis which is consistent with
EPA's 2019 Guidance.\70\ In addition, MANE-VU used several technical,
quantitative methodologies as screening tools to identify states that
are reasonably anticipated to contribute to visibility impairment at
MANE-VU Class I areas. Instead of using contributions estimated by one
method, MANE-VU used the results of each method to develop a relative
ranking of state impacts in determining which states are reasonably
anticipated to contribute to visibility impairment at MANE-VU Class I
areas. In the letter, MANE-VU continues to request that the states
identified by the MANE-VU analyses pursue the measures in the MANE-VU
Inter-RPO Ask. In the letter, MANE-VU also submits the following
observations as to how the individual Ask elements can be addressed in
Tennessee's regional haze SIP submittal: (1) For Ask 1, MANE-VU
recognizes the efforts by Tennessee to reduce SO<INF>2</INF> and
NO<INF>X</INF>, and MANE-VU requests that these emissions reductions be
explicitly documented in Tennessee's regional haze SIP with specific
consideration for whether and how these emissions reductions meet the
MANE-VU Inter-RPO Ask; (2) For Ask 2, MANE-VU notes that there are no
such emission sources in Tennessee; (3) For Ask 3, MANE-VU asks
Tennessee to consider pursuing such fuel standards as enforceable SIP
measures, or to include in its SIP a description of why supply
availability makes the adoption of such standards infeasible; (4) For
Ask 4, MANE-VU respectfully asks that the emission reductions described
in Tennessee's January 13, 2021, letter be documented in Tennessee's
regional haze SIP; and (5) For Ask 5, MANE-VU asks that Tennessee
document in the regional haze SIP any measures or efforts that it is
considering in these areas.
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\70\ ``Guidance on Regional Haze State Implementation Plans for
the Second Implementation Period.'' EPA Office of Air Quality
Planning and Standards, Research Triangle Park (August 20, 2019)
available at: <a href="https://www.epa.gov/sites/default/files/2019-08/documents/8-20-2019_-_regional_haze_guidance_final_guidance.pdf">https://www.epa.gov/sites/default/files/2019-08/documents/8-20-2019_-_regional_haze_guidance_final_guidance.pdf</a>.
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Tennessee believes that the State fulfilled the consultation
requirements in 40 CFR 51.308(f)(2)(ii) by the State's active
participation in a series of five MANE-VU consultation calls held
during the period from October 20, 2017, to March 23, 2018, and its
documented responses to MANE-VU. Thus, TDEC determined at the time that
no further action is required under the RHR to address MANE-VU's
requests.
Lastly, Tennessee consulted with: (a) other states with sources
contributing to regional haze at Tennessee's Class I areas, including
Georgia, Indiana, Kentucky, Ohio, and Pennsylvania; and (b) states with
Class I areas affected by Tennessee sources, which includes MANE-VU.
Consultation with other states with sources contributing to regional
haze at Tennessee's Class I areas is discussed in Section 10 and
Appendix F of the Haze Plan. Tennessee requested an FFA of the
following sources in other states because these sources exceeded the
sulfate PSAT threshold at one or more of Tennessee's Class I areas:
\71\ Georgia Power Company's Plant Bowen (Plant Bowen) in Georgia;
Tennessee Valley Authority-Shawnee Fossil Plant (TVA-Shawnee) in
Kentucky; Gibson and Indiana Michigan Power DBA AEP Rockport in
Indiana; Genon NE Mgmt Co/Keystone Station (Keystone) in Pennsylvania;
General James M. Gavin Power Plant (Gavin Plant) and Duke Energy Ohio--
Wm. H. Zimmer Station (Duke-Zimmer) in Ohio. TDEC expects that any
state which received a letter requesting an FFA of one or more of the
state's sources will address the request in the state's regional haze
plan whether or not the state was able to respond to TDEC prior to
Tennessee's submission of its Haze Plan.
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\71\ Tennessee requested FFAs of non-VISTAS sources through
VISTAS.
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3. EPA Evaluation: EPA has reviewed Tennessee's source selection
criteria, consideration of the four factors, determinations of controls
necessary for reasonable progress, documentation of technical basis,
interstate consultation, and consideration of the five additional
factors. Based on this review, EPA proposes to find that the LTS meets
the requirements of 40 CFR 51.308(f)(2)(i) through (iv).
a. Source Selection Criteria: EPA proposes to find that Tennessee
has satisfied the requirements of 40 CFR 51.308(f)(2)(i) with respect
to including a description of the criteria that the State used to
determine which sources the State evaluated for emissions controls.
Tennessee provided in the Haze Plan supporting information such as
Appendix C, which includes monitoring and meteorological data used to
support selection of sources; Appendix D, which provides documentation
supporting the AoI analysis (first step of the State's source selection
process); and Appendix E, which details the visibility and source
apportionment data and results from the PSAT modeling (second step of
the State's source selection process). EPA finds this source selection
requirement meets the requirements within 40 CFR 51.308(f)(2).
EPA also proposes to find that Tennessee's source selection
methodology was reasonable and resulted in the selection of a
reasonable set of sources for FFAs. AoI and PSAT are acceptable and
well-established methods for selecting sources for a control
analysis.\72\ Additionally, Tennessee's application of a three percent
AoI threshold and one percent PSAT threshold based on 2028 projected
emissions resulted in the selection of the two in-state sources that
are projected to have the highest impact on visibility at the end of
the second planning period and also identified seven out-of-state
sources that have the largest impacts on visibility at Class I areas in
Tennessee. Tennessee completed control evaluations for the two in-state
sources and requested control evaluations for the seven out-of-state
sources.
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\72\ The State used the AoI process because it identifies the
largest sources with potential visibility impacts to Class I areas
and then used sophisticated photochemical source apportionment
modeling to identify specific sources for control evaluations. See
also 2019 Guidance, pp. 12-13.
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Apart from AoI and PSAT being well-established methods used in the
source selection process, EPA proposes to find that Tennessee's source
selection methodology is also reasonable given the specific
circumstances present in Tennessee. Statewide SO<INF>2</INF> emissions
are expected to decrease in the second planning period from 2017 levels
of 46,738 tpy SO<INF>2</INF> to projected 2028 levels of 23,983 tpy
SO<INF>2</INF> (a 48.7 percent reduction) which occurred after a 70.8
percent decrease in statewide SO<INF>2</INF> emissions from 2011 to
2017 by 113,585
[[Page 40287]]
tpy SO<INF>2</INF>; and statewide NO<INF>X</INF> emissions are expected
to decrease in the second planning period from 2017 levels of 200,581
tpy NO<INF>X</INF> to projected 2028 levels of 136,954 tpy
NO<INF>X</INF> (approximately a 31.7 percent reduction), which occurred
after a 37.8 percent decrease in statewide NO<INF>X</INF> emissions
from 2011 to 2018 by 121,984 tpy NO<INF>X</INF>.\73\
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\73\ Tennessee's statewide emissions of SO<INF>2</INF> and
NO<INF>X</INF> decreased during the period from 2011 to 2018 from
118,721 tpy SO<INF>2</INF> to 43,891 tpy SO<INF>2</INF> and
decreased from 369,496 tpy to 231,676 tpy NO<INF>X</INF>. See Tables
7-9 and 13-12 of the Haze Plan. See also Table 5-2 in Appendix B-2a
of the Haze Plan.
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Tennessee (through VISTAS' analysis) projects that visibility
conditions in 2028 are estimated to improve since the 2000-2004
baseline period by 14.1 deciviews for Great Smoky Mountains and Joyce
Kilmer. Specific to the second planning period, visibility conditions
in Tennessee's Class I areas in 2028 are estimated to improve since the
2014-2018 period by 2.2 deciviews and 2.3 deciviews for the Great Smoky
Mountains and Joyce Kilmer, respectively, on the 20 percent most
impaired days, and these visibility improvements represent
approximately the following amount of visibility improvement from the
2014-2018 period to natural conditions: 30.4 percent and 32.5 percent,
respectively, for Great Smoky Mountains and Joyce Kilmer.\74\ Using
2018-2022 IMPROVE data \75\ for Tennessee's Class I areas on the 20
percent most impaired days, Tennessee has already achieved in the first
four years of the second planning period (2019-2022) the following
amount of visibility improvement towards natural conditions: 25.3
percent for both Great Smoky Mountains and Joyce Kilmer.\76\ EPA thus
proposes to find that the State appropriately focused on controlling
point source SO<INF>2</INF> emissions based on objective application of
the State's PSAT thresholds as well as data showing ammonium sulfate is
the dominant visibility impairing pollutant at the Tennessee Class I
areas. Based on an objective application of the State's PSAT thresholds
as well as data showing ammonium sulfate is the dominant visibility
impairing pollutant at the Tennessee Class I areas, EPA proposes to
find that the State appropriately focused on evaluating point source
SO<INF>2</INF> emissions control measures.
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\74\ The additional visibility improvement needed to reach
natural conditions at the start of the second planning period based
upon 2014-2018 IMPROVE data for the 20 percent most impaired days is
calculated as follows: ((2014-2018 visibility conditions)-(2028
RPG))/((2014-2018 visibility conditions)-(natural conditions)) x 100
= percent progress needed to reach natural conditions from the start
of the second planning period. For example, using data for Great
Smoky Mountains, the calculation is: ((17.21 deciviews-15.03
deciviews)/(17.21 deciviews-10.05 deciviews)) x 100 = 30.4 percent.
\75\ The 2018-2022 IMPROVE data for the 20 percent most impaired
days was obtained from <a href="https://vista.cira.colostate.edu/Improve/rhr-summary-data/">https://vista.cira.colostate.edu/Improve/rhr-summary-data/</a> under the header ``Means for Impairment Metric:'' The
IMPROVE data includes visibility monitoring data for each Class I
area. This data was filtered for each Tennessee Class I area, listed
as ``GRSM1'' for both Great Smoky Mountains and Joyce Kilmer,
respectively, (in column ``A'', titled ``site''). Then data was
filtered for the years 2018 through 2022 (using column ``B'' titled
``year''). These data points were then filtered for the 20 percent
most impaired days, indicated by ``90'' (in column ``C'' titled
``impairment_Group''). The resulting five data points for each
Tennessee Class I area within the ``haze_dv'' column ``AK'',
corresponding to each of the five years, were averaged to determine
the 20 percent most impaired days for the 2018-2022 five-year
period. The 2018-2022 IMPROVE data for Tennessee's Class I areas
are: 15.4 deciviews (Great Smoky Mountains and Joyce Kilmer).
\76\ Percentage of progress toward natural conditions = [((2014-
2018 IMPROVE data)-(2018-2022 IMPROVE data))/((2014-2018 IMPROVE
data)-(Natural visibility conditions))] x 100. Example calculation
for Great Smoky Mountains: [(17.21-15.4)/(17.21-10.05)] x 100 = 25.3
percent.
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b. Consideration of the Four CAA Factors: In this section of the
document, EPA evaluates Tennessee's LTS against the requirements of the
CAA and RHR for the second planning period. As detailed further below
and for the reasons discussed throughout this Section IV(C)(3)(b) of
the NPRM, EPA proposes to approve Tennessee's LTS under 40 CFR
51.308(f)(2).
In this proposed action, EPA notes that it is the Agency's policy,
as announced in the recent proposed action for West Virginia's Regional
Haze SIP for the second planning period, that, where visibility
conditions for a Class I area impacted by a State are below the URP and
the State has evaluated potential control measures and considered the
four statutory factors, the State will have presumptively demonstrated
reasonable progress for the second planning period for that
area.<SUP>77 78</SUP> EPA acknowledges that this proposed action
reflects a change in policy from current guidance as to how the URP
should be used in the evaluation of regional haze second planning
period SIPs. EPA has the discretion and authority to change policy. In
FCC v. Fox Television Stations, Inc., the U.S. Supreme Court plainly
stated that an agency is free to change a prior policy and ``need not
demonstrate . . . that the reasons for the new policy are better than
the reasons for the old one; it suffices that the new policy is
permissible under the statute, that there are good reasons for it, and
that the agency believes it to be better.'' 566 U.S. 502, 515 (2009)
(referencing Motor Vehicle Mfrs. Ass'n of United States, Inc. v. State
Farm Mut. Auto. Ins. Co., 463 U.S. 29 (1983)). See also Perez v.
Mortgage Bankers Assn., 135 S. Ct. 1199 (2015). EPA believes that this
policy aligns with the purpose of the statute and RHR, which is
achieving ``reasonable'' progress, not maximal progress, toward
Congress' natural visibility goal.
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\77\ See 90 FR 16478, 16483 (April 18, 2025).
\78\ See also EPA's May 14, 2025, proposed action for South
Dakota's Regional Haze SIP for the second planning period (90 FR
20425).
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In developing the regulations required by CAA section 169A(b), EPA
established the concept of the URP for each Class I area. As discussed
above, for each Class I area, there is a regulatory requirement to
compare the projected visibility impairment (represented by the RPG) at
the end of each planning period to the URP (e.g., in 2028 for the
second planning period).\79\
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\79\ EPA notes that RPGs are a regulatory construct that EPA
developed to address statutory mandate in CAA section 169B(e)(1),
which required our regulations to include ``criteria for measuring
`reasonable progress' toward the national goal.'' Under 40 CFR
51.308(f)(3)(ii), RPGs measure the progress that is projected to be
achieved by the control measures a state has determined are
necessary to make reasonable progress. Consistent with the 1999 RHR,
the RPGs are unenforceable, though they create a benchmark that
allows for analytical comparisons to the URP and mid-implementation-
period course corrections if necessary. See 82 FR 3091-3092 (January
10, 2017).
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In the 2017 RHR Revisions, EPA addressed the role of the URP as it
relates to a state's development of its second planning period SIP. See
82 FR 3078 (January 10, 2017). Specifically, in response to comments
suggesting that the URP should be considered a ``safe harbor'' and
relieve states of any obligation to consider the four statutory
factors, EPA explained that the URP was not intended to be such a safe
harbor. EPA summarized such comments as follows: ``Some commenters
stated a desire for corresponding rule text dealing with situations
where RPGs are equal to (``on'') or better than (``below'') the URP or
glidepath. Several commenters stated that the URP or glidepath should
be a ``safe harbor,'' opining that states should be permitted to
analyze whether projected visibility conditions for the end of the
implementation period will be on or below the glidepath based on on-
the-books or on-the-way control measures, and that in such cases a
four-factor analysis should not be required.'' \80\
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\80\ See 82 FR 3099 (January 10, 2017).
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Other 2017 RHR comments indicated a similar approach, such as ``a
somewhat narrower entrance to a `safe
[[Page 40288]]
harbor,' by suggesting that if current visibility conditions are
already below the end-of-planning-period point on the URP line, a four-
factor analysis should not be required.'' \81\ EPA was clear in its
response: ``We do not agree with either of these recommendations.'' EPA
explained its position as follows: ``The CAA requires that each SIP
revision contain long-term strategies for making reasonable progress,
and that in determining reasonable progress states must consider the
four statutory factors. Treating the URP as a safe harbor would be
inconsistent with the statutory requirement that states assess the
potential to make further reasonable progress towards natural
visibility goal in every implementation period.'' \82\
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\81\ Id.
\82\ Id.
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In EPA's new policy, if the Class I areas impacted by a state are
below the URP and the State considers the four factors, the State will
have presumptively demonstrated it has made reasonable progress for the
second planning period for that area. Indeed, EPA believes this policy
also recognizes the considerable improvements in visibility impairment
that have been made by a wide variety of state and federal programs in
recent decades.
EPA finds that Tennessee considered the four statutory factors in
the assessment of the potential for additional controls to make
reasonable progress and the projected 2028 visibility conditions for
Class I areas influenced by emissions from Tennessee sources are all
below the URP. For these reasons and for the reasons discussed
throughout this Section IV(C)(3)(b) of the NPRM, Tennessee's SIP
submittal is reasonable and meets the requirements of 40 CFR
51.308(f)(2). EPA's specific conclusions regarding the FFAs for Eastman
and TVA-Cumberland are discussed in more detail below.
i. Eastman: Regarding Eastman, EPA proposes to find that TDEC's
conclusions and analytical methods stated in its FFA for Boilers 21,
22, 23, 24, 30, and 31 are reasonable. EPA also proposes to find the
state's conclusions for Boilers 18, 19, and 20 are reasonable.
Regarding Boilers 18-20, as additional context to Tennessee's
submittal, EPA notes that these units were constructed in the 1940s and
did not provide electricity to the grid. Also, as noted above, the
replacement gas boilers for these units have been constructed and are
now operational.
EPA agrees with TDEC's determination that the permanent shutdown of
these units no later than December 31, 2028, is necessary for
reasonable progress. Thus, EPA proposes to adopt into the Tennessee SIP
the requirement that Boilers 18, 19, and 20 at Eastman will cease
operating no later than December 31, 2028, as specified in Condition 2
of Permit 079592. EPA also notes that these units have fully shut down
and are incapable of restarting without undergoing applicable New
Source Review permitting for new sources. The replacement gas boilers
for these units have been constructed and are now operational.\83\
Eastman was required to cease operation of Boilers 18, 19, and 20 based
on permit condition G18 in Construction Permit Number 979100, which
provides that ``[t]he permittee shall permanently cease operation of
Boilers 18, 19, and 20 (82-0003-01/PES B-83-1) as follows:'' ``Boiler
19 shall cease operation on or before the startup date of Boiler 32'';
``Boiler 18 shall cease operation on or before the startup date of
Boiler 33''; and ``Boiler 20 shall cease operation on or before the
startup date of Boiler 34.'' The condition also includes the following
compliance method: ``The permittee shall notify the Technical Secretary
in writing of the shutdown date of each boiler no later than 30 days
after the date of each shutdown. The notification shall be submitted to
the Technical Secretary at the address identified in Condition G3 of
this permit.''
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\83\ See the startup notifications for Boilers 32, 33, and 34
included in the docket of this proposed action.
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Regarding Boilers 23 and 24, EPA proposes to agree with TDEC's
conclusions to adopt a combined SO<INF>2</INF> emissions limit which
shall not collectively exceed 1,396 tons of SO<INF>2</INF> during any
period of 12 consecutive months into the Tennessee SIP. This is a new
measure as necessary for reasonable progress as specified in Condition
1 of Permit No. 079592. Eastman plans to meet this limit through
installation of permanent DSI, as specified in Section 7.8.1 and
Appendix G-2 of the Haze Plan and as specified in Condition 2 of Permit
No. 080222.\84\
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\84\ Title V Operating Permit No. 080222 is included in the
docket for this proposed action.
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Because EPA proposes to approve TDEC's conclusions and analytical
methods with respect to Boilers 21, 22, 30, and 31. While Boilers 21
and 22 are not currently equipped with any SO<INF>2</INF> controls,
based on the cost analyses submitted by Tennessee, EPA agrees with the
State's determination to not require any additional SO<INF>2</INF>
controls for these units during this planning period. Regarding the
cost-effectiveness for each of the controls evaluated in TDEC's
adjusted interest rate and equipment life of Eastman's FFA, the lowest
cost per ton identified for Boilers 21 and 22 was for the addition of
DSI along with the fabric filters at $6,342/ton of SO<INF>2</INF>
removed. The State's assessment that this cost is not cost-effective is
reasonable.
Regarding Boiler 30, EPA proposes to find that TDEC reasonably
determined that the cost of replacing the existing ESP with a fabric
filter is not cost-effective and that there is no control option beyond
the current controls that is appropriate for Boiler 30 for the second
planning period. Regarding Boiler 31, EPA proposes to find that TDEC
reasonably determined that this unit is effectively controlled for
SO<INF>2</INF>, as it is equipped with a SDA followed by a fabric
filter, which achieves an SO<INF>2</INF> control efficiency of greater
than 92 percent.
Although not included as part of its Regional Haze Plan,
Tennessee's 2023 Plan submittal to EPA includes existing measures that
apply to Boilers 21, 22, 30, and 31. In the letter submitted to EPA on
December 20, 2024, TDEC requested that EPA incorporate these measures
into Tennessee's SIP to support Tennessee's regional haze SIP. These
measures are discussed separately in Section V of this NPRM.
ii. TVA-Cumberland: Regarding TVA-Cumberland, EPA proposes to find
that TDEC's conclusions and analytical methods stated in its FFA for
the coal boilers are reasonable. Tennessee determined that no
additional emission reduction measures are necessary at TVA-Cumberland
to make reasonable progress during the regional haze second planning
period. TDEC rejected the installation of wall rings along the scrubber
walls and the redesign and replacement of spray headers and nozzles on
the basis of cost in comparing the values to the costs identified by
VISTAS for similar options, which was adequately explained in Appendix
G-1 of the Haze Plan. The installation of wall rings resulted in a
cost-effectiveness of $2,881/ton of SO<INF>2</INF> reduced. EPA finds
TDEC's determination that no additional controls are needed to be
reasonable and agrees with TDEC's conclusions that the cost-
effectiveness for installing wall rings is higher than the median cost
for similar options and that other comparable emission reduction
measures within a similar cost-effectiveness values have substantial
emissions reductions and associated co-benefits when compared to the
emissions reductions from the installation of the wall wings.
[[Page 40289]]
Tennessee also rejected the redesign and replacement of spray
headers and nozzles due to the high costs of compliance. As noted in
Appendix G-1 of the Haze Plan, Tennessee found that the cost-
effectiveness of the redesign and replacement of spray headers and
nozzles resulted in a cost-effectiveness of $5,059 per ton of
SO<INF>2</INF> reduced. Tennessee also evaluated the other three
statutory factors. The time necessary for compliance was considered,
and Tennessee did not eliminate any control options from consideration
as a result of that factor. Tennessee raised concerns about certain
energy and non-air quality impacts, but did not eliminate any controls
from consideration solely because of these impacts. Lastly, Tennessee's
considered the remaining useful life of Units 1 and 2. Tennessee
concluded that no additional measures at TVA-Cumberland are necessary
to make reasonable progress for the second planning period. EPA finds
that Tennessee has demonstrated that it would make reasonable progress
for the second planning period without any additional measures for TVA-
Cumberland.
c. Assessment of Five Additional Factors in 40 CFR
51.308(f)(2)(iv): EPA proposes to find that Tennessee has satisfied the
requirements of 40 CFR 51.308(f)(2)(iv) because TDEC considered each of
the five additional factors under 40 CFR 51.308(f)(2)(iv) in developing
Tennessee's LTS, discussed the measures the State has in place to
address each factor (or discussed why such measures are not needed),
and, where relevant, explained how each factor informed VISTAS'
technical analyses for the second planning period.
With respect to 40 CFR 51.308(f)(2)(iv)(A), Tennessee has
adequately addressed the requirement to assess emission reductions due
to ongoing air pollution control programs, including measures to
address RAVI, through the State's emissions inventory work for the base
year of 2011 as projected out to 2028.
With respect to 40 CFR 51.308(f)(2)(iv)(B), Tennessee adequately
addressed this requirement to evaluate measures to mitigate the impacts
of construction activities by describing various state regulations that
address control pollution from construction activities and that require
subject facilities to control PM from fugitive dust emission sources
generated within plant boundaries and explaining that fine soils were a
relatively minor contributor to visibility impairment at Great Smoky
Mountains (also Joyce Kilmer) during the 2000-2004 baseline period as
demonstrated in Figure 2-2 of the Haze Plan, and that no VISTAS Class I
areas experienced significant visibility impairment from soils during
the baseline timeframe as demonstrated in Figure 2-3. As demonstrated
by Figures 2-7, 2-8, 2-9, soils continued to be a minor contributor to
visibility impairment at Great Smoky Mountains (also Joyce Kilmer) and
other VISTAS Class I areas through the 2014-2018 time period.
With respect to 40 CFR 51.308(f)(2)(iv)(C), EPA proposes to find
that Tennessee has adequately addressed source retirement and
replacement schedules by summarizing existing and planned source
retirements throughout the Haze Plan, including in Section 7.2.2
(retirements accounted for in the 2028 inventory/RPGs).
With respect to 40 CFR 51.308(f)(2)(iv)(D), EPA proposes to find
that Tennessee adequately addressed the requirement to consider the
State's basic smoke management practices for prescribed fire used for
agricultural and wildland vegetation management purposes and smoke
management programs. The State describes its promulgated regulations
under the Division of Forestry (Tennessee Rule 0080-07-06), which
regulates prescribed fires, sets guidelines for prescribed burn
prescription and TDEC (Tennessee Rule 1200-03-04), which sets specific
circumstances in which open burning is permissible. In addition, the
State describes the November 24, 2021, MOU which requires that all
parties follow basic smoke management practices when utilizing
prescribed burning in order to mitigate PM<INF>2.5</INF> emissions and
regional haze impacts and highlights interagency coordination related
to open burning and related topics.
With respect to 40 CFR 51.308(f)(2)(iv)(E), EPA proposes to find
that Tennessee assessed the anticipated net effect on visibility due to
projected changes in point, area, and mobile source emissions over the
second period in development of the 2028 RPGs for the Tennessee Class I
areas in Section 8 of the Haze Plan. TDEC used the 2011 base year
emissions inventory to project emissions from various source sectors to
2028, the end of the second planning period. TDEC, through VISTAS,
completed CAMx modeling to estimate visibility impairment in 2028 based
on projected 2028 emissions from the 2011 base year inventory and using
IMPROVE monitoring data for 2009-2013.\85\ For Tennessee, estimated
visibility improvements by 2028 in each Class I area are based on:
estimated emissions reductions associated with existing federal and
state measures implemented or expected to be implemented during the
second planning period; emissions reductions associated with facility
closures that occurred after the 2016 point source emissions base year
(i.e., January 1, 2017, through November 18, 2018); and estimates of
emissions changes associated with economic growth and other factors.
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\85\ In preparing the 2028 emissions for point sources, TDEC
started with a 2016 base year inventory which include emission
reductions associated with federal and state control programs and
consent decrees included in the LTS for the first planning period.
---------------------------------------------------------------------------
d. Interstate Consultation: With respect to interstate consultation
pursuant to 40 CFR 51.308(f)(2)(ii), EPA proposes to find that
Tennessee has met the requirements under 40 CFR 51.308(f)(2)(ii) to
consult with those states with Class I areas where Tennessee emissions
may reasonably be anticipated to cause or contribute to visibility
impairment and to consult with those States whose sources may
reasonably be anticipated to cause or contribute to visibility
impairment at Tennessee's Class I areas. With respect to other states'
requests for Tennessee to complete FFAs for TVA-Cumberland and Eastman,
Tennessee did so. With respect to consultation with other States with
visibility impacts to Tennessee's Class I areas, Tennessee adequately
documented the responses from consulted states in Appendix F, provided
a summary of its consultation in Section 10.1.1, and identified whether
the State agrees with the conclusions.
With respect to the MANE-VU Ask, Tennessee adequately took actions
to address points of disagreements with MANE-VU related to Tennessee's
statewide impacts by providing technical analysis and rationale to
resolve the varying viewpoints between the two organizations. Tennessee
satisfactorily documented in Appendix F-4 of the Haze Plan the State's
disagreements by sending a letter dated December 22, 2017, to MANE-VU
documenting the response to the points of disagreements in addition to
supporting the January 27, 2018, letter from VISTAS to MANE-VU.\86\
With respect to consultation with other states with visibility impacts
to Tennessee's Class I areas, TDEC adequately
[[Page 40290]]
documented the responses from consulted states in Appendix F and as
summarized in Section 10.1.1 and identified whether the State agrees
with the conclusions.
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\86\ Appendix F-4 of the Haze Plan contains the January 27,
2018, and January 13, 2021, letters along with a letter dated August
25, 2017, in which MANE-VU requested consultation with Tennessee
because Tennessee exceeds the MANE-VU visibility impact threshold
for at least one Class I area in the MANE-VU region.
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D. RPGs
1. RHR Requirement: 40 CFR 51.308(f)(3) contains the requirements
pertaining to RPGs for each Class I area. 40 CFR 51.308(f)(3)(i)
requires a state in which a Class I area is located to establish RPGs--
one each for the most impaired and clearest days--reflecting the
visibility conditions that will be achieved at the end of the planning
period as a result of the emission limitations, compliance schedules,
and other measures required under paragraph (f)(2) to be in states'
LTSs, as well as implementation of other CAA requirements. The LTSs, as
reflected by the RPGs, must provide for an improvement in visibility on
the most impaired days relative to the baseline period and ensure no
degradation on the clearest days relative to the baseline period. 40
CFR 51.308(f)(3)(ii) applies in circumstances in which a Class I area's
RPG for the most impaired days represents a slower rate of visibility
improvement than the URP calculated under 40 CFR 51.308(f)(1)(vi).
Under 40 CFR 51.308(f)(3)(ii)(A), if the state in which a mandatory
Class I area is located establishes an RPG for the most impaired days
that provides for a slower rate of visibility improvement than the URP,
the state must demonstrate that there are no additional emission
reduction measures for anthropogenic sources or groups of sources in
the state that would be reasonable to include in its LTS. 40 CFR
51.308(f)(3)(ii)(B) requires that if a state contains sources that are
reasonably anticipated to contribute to visibility impairment in a
Class I area in another state, and the RPG for the most impaired days
in that Class I area is above the URP, the upwind state must provide
the same demonstration.
2. State Assessment: Tennessee established 2028 RPGs for each of
its Class I areas in deciviews for the 20 percent clearest days and the
20 percent most impaired in Tables 8-1 and 8-2, respectively, of the
Haze Plan, which are all projected to remain below the URP for each
Class I area based on VISTAS' modeling. Table 3 summarizes the 2028
RPGs and 2028 URPs for Tennessee's Class I areas.
Table 3--Tennessee's Class I Area RPGs and URPs for 2028 in Deciviews (dv)
----------------------------------------------------------------------------------------------------------------
2028 RPG 20%
Class I area 2028 RPG 20% most impaired 2028 URP (dv)
clearest (dv) (dv)
----------------------------------------------------------------------------------------------------------------
Great Smoky Mountains..................................... 8.96 15.03 21.49
Joyce Kilmer.............................................. 8.96 15.03 21.49
----------------------------------------------------------------------------------------------------------------
Figure 3-1 of the Haze Plan show the URP for the 20 percent most
impaired days for Great Smoky Mountains (also Joyce Kilmer).
3. EPA Evaluation: Tennessee provided 2028 RPGs for its Class I
area for the most impaired and clearest days. The State established
2028 RPGs expressed in deciviews that reflect the visibility conditions
that are projected to be achieved by the end of the second planning
period as a result of implementation of the LTS and other CAA
requirements. Tennessee's RPGs provide for an improvement in visibility
for the 20 percent most impaired days since the baseline period (2000-
2004) and demonstrate that there is no degradation in visibility for
the 20 percent clearest days since the baseline period. Any additional
unanticipated emissions reductions provide further assurances that the
State's Class I area will achieve its 2028 RPGs.
For these reasons, the 2028 RPGs for Great Smoky Mountains (also
Joyce Kilmer) are reasonable. Additionally, Tennessee has adequately
demonstrated that all Class I areas both in Tennessee and out-of-state
Class I areas to which Tennessee may reasonably be anticipated to cause
or contribute to any impairment of visibility are all below the URP.
Therefore, the ``robust demonstration'' provisions in 40 CFR
51.308(f)(3)(ii) are not applicable to this action. As such, EPA is
proposing to determine that Tennessee has satisfied all applicable
requirements of 40 CFR 51.308(f)(3).
E. Monitoring Strategy and Other Implementation Plan Requirements
1. RHR Requirement: 40 CFR 51.308(f)(6) specifies that each
comprehensive revision of a state's regional haze SIP must contain or
provide for certain elements, including monitoring strategies,
emissions inventories, and any reporting, recordkeeping and other
measures needed to assess and report on visibility. A main requirement
of this section is for states with Class I areas to submit monitoring
strategies for measuring, characterizing, and reporting on visibility
impairment. Compliance with this requirement may be met through
participation in the IMPROVE network.
40 CFR 51.308(f)(6)(i) requires SIPs to provide for the
establishment of any additional monitoring sites or equipment needed to
assess whether RPGs to address regional haze for all mandatory Class I
areas within the state are being achieved.
40 CFR 51.308(f)(6)(ii) requires SIPs to provide for procedures by
which monitoring data and other information are used in determining the
contribution of emissions from within the state to regional haze
visibility impairment at mandatory Class I areas both within and
outside the state.
40 CFR 51.308(f)(6)(iii) applies only to states that do not have a
mandatory Class I areas.
40 CFR 51.308(f)(6)(iv) requires the SIP to provide for the
reporting of all visibility monitoring data to the Administrator at
least annually for each Class I area in the state.
40 CFR 51.308(f)(6)(v) requires SIPs to provide for a statewide
inventory of emissions of pollutants that are reasonably anticipated to
cause or contribute to visibility impairment, including emissions for
the most recent year for which data are available and estimates of
future projected emissions. It also requires a commitment to update the
inventory periodically.
40 CFR 51.308(f)(6)(v) also requires states to include estimates of
future projected emissions and include a commitment to update the
inventory periodically. Under 40 CFR 51.308(f)(4), if EPA or the FLM of
an affected Class I area has advised a state that additional monitoring
is needed to assess RAVI, the state must include in its SIP revision
for the second planning period an appropriate strategy for evaluating
such impairment.
2. State Assessment: With respect to 40 CFR 51.308(f)(6)(i),
Tennessee believes the existing IMPROVE monitor for the State's Class I
areas is adequate and does not believe any additional
[[Page 40291]]
monitoring sites or equipment are needed to assess whether the RPGs for
all Class I areas within the State are being achieved.
With respect to 40 CFR 51.308(f)(6)(ii), data from this IMPROVE
monitor will be used for the future haze plans and progress reports.
40 CFR 51.308(f)(6)(iii) does not apply to Tennessee because it has
a Class I area.
With respect to 40 CFR 51.308(f)(6)(iv), NPS manages and oversees
the IMPROVE monitoring network. The IMPROVE monitoring network samples
PM from which the chemical composition of the sampled particles is
determined and is then used to calculate visibility. NPS is responsible
for collecting, reviewing, validated, and verifying IMPROVE data before
submission to EPA's Air Quality System (AQS). Tennessee's participation
in the IMPROVE Steering Committee and the IMPROVE monitoring network
addresses this requirement. Tennessee believes the existing IMPROVE
monitors for the State's Class I areas are sufficient for the purposes
of this SIP revision.
With respect to 40 CFR 51.308(f)(6)(v), TDEC provided a statewide,
baseline emissions inventory of pollutants for the year 2011 in Table
4-2 of the Haze Plan which includes the following pollutants:
NO<INF>X</INF>, SO<INF>2</INF>, VOC, NH<INF>3</INF>, PM<INF>2.5</INF>,
and PM<INF>10</INF>. The 2011 baseline emissions year was used because
emissions and modeling work needs to begin three years before haze
plans are due because of the significant amount of time required to
complete the work one year in advance of preparing the haze plans. The
2011 base year modeling platform was the best platform available at the
time the modeling work began in early 2018. TDEC, through VISTAS,
discussed the selection of modeling platforms with EPA and reliance on
the 2011 base year. Tennessee will continue to participate in SESARM/
VISTAS efforts for projecting future emissions and continue to comply
with the requirements of the Air Emissions Reporting Requirements
(AERR) to periodically update emissions inventories under 40 CFR
51.308(f)(6)(v).\87\
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\87\ See Haze Plan at p. 217.
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With respect to 40 CFR 51.308(f)(6)(vi), Tennessee affirms that
there are no elements, including reporting, recordkeeping, or other
measures, necessary to address and report on visibility for Tennessee's
Class I areas or Class I areas outside the State that are affected by
sources in Tennessee. With respect to 40 CFR 51.308(f)(4), the State
did not include a strategy for evaluating RAVI for any Class I areas
because no Federal agency requested additional monitoring to assess
RAVI.
3. EPA Evaluation: EPA proposes to determine that Tennessee has
satisfied the applicable requirements of 40 CFR 51.308(f)(4) and 40 CFR
51.308(f)(6) related to RAVI, visibility monitoring, and emissions
inventories. With respect to 40 CFR 51.308(f)(4), EPA proposes to find
that this requirement does not apply to Tennessee at this time because
neither EPA nor the FLMs requested additional monitoring to assess
RAVI.
EPA proposes to determine that Tennessee has satisfied 40 CFR
51.308(f)(6), which is generally met by the State's continued
participation in the IMPROVE monitoring network and the VISTAS RPO, for
the following reasons. With respect to 40 CFR 51.3089(f)(6)(i),
Tennessee stated that the existing IMPROVE monitors relied upon for the
State's two Class I areas are adequate, and thus, additional monitoring
sites or equipment are not needed to assess whether the RPGs for all
Class I areas within the State are being achieved. With respect to 40
CFR 51.308(f)(6)(ii), Tennessee is complying with procedures by which
monitoring data and other information are used to determine the
contribution of emissions from within the State to regional haze at
Class I areas both within and outside the State through Tennessee's
continued participation in VISTAS' regional haze work. With respect to
40 CFR 51.308(f)(6)(iii), this provision is applicable for states with
no Class I areas and does not apply to Tennessee. Regarding the
reporting of visibility monitoring data to EPA at least annually for
each Class I area in the State pursuant to 40 CFR 51.308(f)(6)(iv), EPA
proposes to find that Tennessee's participation in the IMPROVE Steering
Committee and the IMPROVE monitoring network addresses this
requirement. With respect to 40 CFR 51.308(f)(6)(v), EPA proposes to
find that Tennessee's continued participation in VISTAS' efforts for
projecting future emissions and continued compliance with the
requirements of the AERR to periodically update emissions inventories
satisfies the requirement to provide for an emissions inventory for the
most recent year for which data are available. EPA proposes to find
that Tennessee adequately documented that no further elements are
necessary at this time for the State to assess and report on visibility
pursuant to 40 CFR 51.308(f)(6)(vi).
F. Requirements for Periodic Reports Describing Progress Toward the
RPGs
1. RHR Requirement: Section 51.308(f)(5) requires that periodic
comprehensive revisions of states' regional haze plans also address the
progress report requirements of 40 CFR 51.308(g)(1)-(5). The purpose of
these requirements is to evaluate progress towards the applicable RPGs
for each Class I area within the state and each Class I area outside
the state that may be affected by emissions from within that state. 40
CFR 51.308(g)(1) and (2) apply to all states and require a description
of the status of implementation of all measures included in a state's
first planning period regional haze plan and a summary of the emission
reductions achieved through implementation of those measures. 40 CFR
51.308(g)(3) applies only to states with Class I areas within their
borders and requires such states to assess current visibility
conditions, changes in visibility relative to baseline (2000-2004)
visibility conditions, and changes in visibility conditions relative to
the period addressed in the first planning period progress report. 40
CFR 51.308(g)(4) applies to all states and requires an analysis
tracking changes in emissions of pollutants contributing to visibility
impairment from all sources and sectors since the period addressed by
the first planning period progress report. This provision further
specifies the year or years through which the analysis must extend
depending on the type of source and the platform through which its
emission information is reported. Finally, 40 CFR 51.308(g)(5), which
also applies to all states, requires an assessment of any significant
changes in anthropogenic emissions within or outside the state have
occurred since the period addressed by the first planning period
progress report, including whether such changes were anticipated and
whether they have limited or impeded expected progress towards reducing
emissions and improving visibility.
2. State Assessment: With respect to the progress report elements
pursuant to 40 CFR 51.308(f)(5), the State addressed these elements in
Section 13 of the Haze Plan for the period 2013 to 2018, the end of the
first period.\88\ Tennessee outlines its approach to addressing 40 CFR
51.308(g)(1) through 40 CFR 51.308(g)(5) in Section 13.2 of the Haze
Plan.
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\88\ Tennessee's first period progress report covered the period
from 2008-2012.
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Regarding 40 CFR 51.308(g)(1) and 40 CFR 51.308(g)(2), the State
describes the
[[Page 40292]]
status of the implementation of the measures of the LTS from the first
planning period in Section 13.3.1 and provides a summary of the
emission reductions achieved by implementing those measures in Sections
13.3 and 13.5 of the Haze Plan.
With respect to 40 CFR 51.308(g)(1), the Haze Plan identifies key
Federal and state emissions control measures in Section 13.3.1 that the
State relied upon for other emission reduction actions included in the
LTS of Tennessee's first regional haze plan submitted on April 4, 2008.
Section 13.3.2 identifies measures that contributed to emission
reductions during the first planning period but were not a part of the
LTS for the first period.\89\ In Section 13.3.1.1 of the Haze Plan,
Tennessee summarized Federal and state programs which contributed to
reductions of EGU and certain non-EGU SO<INF>2</INF> emissions in
Tennessee and surrounding states over the 2013-2018 period. The
programs examined include, but are not limited to, the 2005 Clean Air
Interstate Rule, the Phase I NO<INF>X</INF> SIP Call, and consent
agreements and voluntary agreements with regional EGUs. In Section
13.3.1.2 of the Haze Plan, the State summarized state EGU control
measures which contributed to reductions in SO<INF>2</INF> emissions in
Tennessee, North Carolina, and Georgia. The programs examined included
the 2002 North Carolina Clean Smokestacks Act, the 2007 Georgia Multi-
Pollutant Control for Electric Utility Steam Generating Units, and
Tennessee's Reasonable Progress and BART Control Measures.
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\89\ For the first planning period, visibility conditions were
determined for the average of the 20 percent most impaired
visibility days (referred to as the ``worst'' days) and the 20
percent least impaired visibility days (referred to as the ``best''
days).
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With respect to 40 CFR 51.308(g)(2), Tennessee continued to focus
on SO<INF>2</INF> emissions reductions because the State determined
that ammonium sulfate was the most important contributor to visibility
impairment and fine particle on the 20 percent best and 20 percent
worst visibility days at all the Tennessee Class I areas. Section 13.3
of the Haze Plan identifies control measures included in the LTS for
Tennessee's first regional haze plan submitted in 2008 (``2008 Haze
Plan''), and Table 13-3 of the Haze Plan separately identifies the
Maximum Achievable Control Technology standards relied upon for the
2008 Haze Plan. The controls listed in Section 13.1 and in Table 13-4
also identify actions that were not anticipated when Tennessee prepared
the LTS for the 2008 Haze Plan which contributed to emission reductions
during the first planning period. Section 13.3.2 identifies which
measures were modeled for the 2018 RPGs for the first planning period.
With respect to Tennessee's EGUs, Table 7-1 of the Haze Plan lists
the coal-fired EGUs in Tennessee that were projected in the 2008 Haze
Plan to have emissions controls installed by 2018. The EGU sector in
Tennessee represents over 50 percent of statewide SO<INF>2</INF>
emissions from stationary sources. Section 7.2.2 of the Haze Plan also
identifies EGU retirement dates, if applicable. The shutdown of
Tennessee's coal-fired EGUs (TVA-Allen, TVA-John Sevier, TVA-
Johnsonville, summarized in Table 7-1) decreased SO<INF>2</INF>
emissions by 91.7 percent from 10,974 tpy to 916 tpy from 2011 to 2018.
Tennessee's coal-fired EGUs decreased NO<INF>X</INF> emissions by 80.9
percent from 2011 to 2018 from 2,557 tpy to 488 tpy. TDEC identifies
the North Carolina Clean Smokestacks Act (CSA) \90\ as one of the most
important actions that North Carolina implemented to achieve early
reductions for improving visibility in North Carolina's Class I areas.
The CSA was a component of the LTS of the 2008 Haze Plan. In 2011,
these sources emitted only 73,454 tons of SO<INF>2</INF> and 39,284
tons of NO<INF>X</INF>, well below the Act's system caps (250,000 tons
of SO<INF>2</INF> and 56,000 tons of NO<INF>X</INF>).
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\90\ The CSA is a North Carolina law which required the coal-
fired EGUs subject to the CSA to reduce annual NO<INF>X</INF>
emissions by 77 percent by 2009 and to reduce annual SO<INF>2</INF>
emissions by 49 percent by 2009 and 73 percent by 2013. This law set
a NO<INF>X</INF> emissions cap of 56,000 tpy starting in 2009 and
SO<INF>2</INF> emissions caps of 250,000 tpy and 130,000 tpy
starting in 2009 and 2013, respectively. The affected EGUs were
equipped with scrubbers to control SO<INF>2</INF> and either SCR or
selective non-catalytic reduction (SNCR) to control NO<INF>X</INF>
emissions.
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Section 13.3 of the Haze Plan also provides emissions reductions
for the following non-EGUs which were selected for an FFA in the first
planning period: Alcoa, Dupont Old Hickory, Eastman, and TVA-
Cumberland. In the 2008 Haze Plan, no new SO<INF>2</INF> measures were
found reasonable in the first planning period. SO<INF>2</INF> emissions
from these five facilities collectively decreased by 75 percent from
2008 to 2018 from 38,409 tpy to 9,775 tpy.
With respect to 40 CFR 51.308(g)(3), in Tables 13-5 through 13-9 of
the Haze Plan, TDEC calculated the following for the two Class I areas:
current visibility conditions (2014-2018), changes in visibility
relative to baseline (2000-2004) visibility conditions, and changes in
visibility conditions compared to the last five years. The data show
that all Class I areas saw an improvement in visibility on the 20
percent worst days and on the 20 percent clearest days.\91\
Additionally, TDEC provided data to demonstrate that the current 2014-
2018 monitored values for the Tennessee Class I areas on the 20 percent
worst days are below the 2018 RPGs for the 20 percent worst days.
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\91\ For the first period, visibility conditions were determined
for the average of the 20 percent most impaired visibility days
(referred to as the ``worst'' days) and the 20 percent least
impaired visibility days (referred to as the ``best'' days). These
terms were updated to ``clearest'' and ``most impaired,''
respectively, as part of two recent actions by EPA. See 82 FR 3078
(January 10, 2017) and ``2018 Visibility Tracking Guidance.''
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Regarding 40 CFR 51.308(g)(4), TDEC used the 2014 NEI, the 2017
NEI, and the State's Annual Operating Report point source data
collected each year and compared the emissions from each source
category to the VISTAS 2018 emissions projections in Table 13-10
(PM<INF>2.5</INF>), Table 13-11 (NO<INF>X</INF>), and Table 13-12
(SO<INF>2</INF>) of the Haze Plan. Regarding rPM<INF>2.5</INF>,
NO<INF>X</INF>, and SO<INF>2</INF>, the overall emissions from all
sources (point, area, on-road, non-road, and fires) in the 2017 NEI are
23 percent, 21 percent, and 77 percent lower, respectively, than what
VISTAS projections for each pollutant in 2018. TDEC attributes the
significant SO<INF>2</INF> emissions reductions from point sources
(EGUs and non-EGU point sources). TDEC notes that for compared to the
VISTAS projected PM<INF>2.5</INF> and NO<INF>X</INF> emissions in 2018,
there have been significant reductions for each source category, except
from the fire and on-road category.
With respect to SO<INF>2</INF>, the electric utility sector is the
dominant source of SO<INF>2</INF> emissions in Tennessee. It accounted
for 62 percent and 52 percent of total statewide SO<INF>2</INF>
emissions in 2014 and 2017, respectively. With respect to
NO<INF>X</INF> emissions in Tennessee, emissions from on-road sources
account for approximately 50 percent and emissions from point sources
account for nearly 23 percent, from the 2017 NEI. Overall, from 2014
through 2019, there was an 81 percent and 54 percent decrease in
SO<INF>2</INF> and NO<INF>X</INF> emissions, respectively, from EGU
sources, with a decrease of 22 percent in heat input over this
period.\92\ TDEC notes that the reductions from EGU sources are due to
the installation of controls and the use of cleaner burning fuels.
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\92\ See Table 13-13 and Figure 13-4 of the Haze Plan.
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Despite significant reductions in SO<INF>2</INF>, Tennessee
identifies sulfates as continuing to play a significant role in
visibility impairment, especially for the most anthropogenically
impaired days, as discussed in Section 7.4 of the Haze
[[Page 40293]]
Plan.\93\ As SO<INF>2</INF> emissions continue to drop, nitrates may
begin to have a larger relative impact on regional haze in future
planning periods.
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\93\ Figure 13-1 of the Haze Plan provides the breakdown of
visibility impairing pollutants for the 20 percent worst visibility
days and clearest visibility days in Tennessee's Class I areas over
2011 through 2018 timeframe.
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Regarding 40 CFR 51.308(g)(5), TDEC believes that there does not
appear to be any significant change in anthropogenic emissions within
Tennessee or outside the State that have occurred since the period
addressed in the most recent plan that would limit or impede progress
in reducing pollutant emissions or improving visibility. TDEC reviewed
anthropogenic SO<INF>2</INF> and NO<INF>X</INF> emissions trends for
the VISTAS states and each of the RPOs based on emissions included in
the 2014 and 2017 NEI in Tables 13-10 through 13-13 of the Haze Plan.
These data show a decline in SO<INF>2</INF> and NO<INF>X</INF>
emissions during the 2014 through 2017 period within Tennessee. In
Tennessee, SO<INF>2</INF> emissions decreased from 94,201 tpy (2011) to
46,738 tpy (2014) and NO<INF>X</INF> emissions decreased from 269,201
tpy (2011) to 200,581 tpy (2014).
Figure 2-8 shows the average light extinction for the 20 percent
most impaired days over the period 2014 through 2018 for all Class I
areas in the Southeast and in neighboring non-VISTAS states. Figure 2-9
shows the average light extinction for the 20 percent clearest days
over the period 2014 through 2018 for all Class I areas in the
Southeast and in neighboring non-VISTAS states. These figures
demonstrate that on the 20 percent most impaired days and 20 percent
clearest days in the Class I areas in Tennessee, sulfates continued to
be the major concern during the first planning period. TDEC notes that
there have been significant reductions in SO<INF>2</INF> and
NO<INF>X</INF> emissions in Tennessee as well as in neighboring states
which have resulted in significant improvements in visible range in
Class I areas in Tennessee and in nearby states. Thus, TDEC concludes
that there does not appear to be any anthropogenic emissions within
Tennessee that would have limited or impeded progress in reducing
pollutant emissions or improving visibility.
3. EPA Evaluation: EPA proposes to find that TDEC has met the
requirements of 40 CFR 51.308(g)(1)-(5) because the Haze Plan
adequately describes the status of the measures included in the LTS
from the first planning period and the emission reductions achieved
from those measures; the visibility conditions and changes at the
Tennessee Class I areas; an analysis tracking the changes in emissions
since the first planning period progress report using available NEI
emissions data for 2014 and 2017 and annual EGU SO<INF>2</INF>
emissions data from 2014 to 2021; evaluates 2017 NEI data which is the
most recent triennial emissions inventory submission from Tennessee
prior to submission of the Haze Plan; and assessed whether any
significant changes in anthropogenic emissions within or outside the
State that have occurred since the end of the period addressed by
Tennessee's first planning period progress report, including whether
these changes in anthropogenic emissions were anticipated in that most
recent plan and whether they have limited or impeded progress in
reducing pollutant emissions and improving visibility. Thus, EPA is
proposing to find that Tennessee has met the requirements of 40 CFR
51.308(f)(5).
G. Requirements for State and FLM Coordination
1. RHR Requirement: Section 169A(d) of the CAA requires states to
consult with FLMs before holding the public hearing on a proposed
regional haze SIP, and to include a summary of the FLMs' conclusions
and recommendations in the notice to the public. In addition, the FLM
consultation provision of 40 CFR 51.308(i)(2) requires a state to
provide the FLMs with an opportunity for consultation that is early
enough in the state's policy analyses of its emission reduction
obligation so that information and recommendations provided by FLMs can
meaningfully inform the state's decisions on its LTS. If the
consultation has taken place at least 120 days before a public hearing
or public comment period, the opportunity for consultation will be
deemed early enough. Regardless, the opportunity for consultation must
be provided at least 60 days before a public hearing or public comment
period at the state level. 40 CFR 51.308(i)(2) also provides two
substantive topics on which FLMs must be provided an opportunity to
discuss with states: assessment of visibility impairment in any Class I
area and recommendations on the development and implementation of
strategies to address visibility impairment. 40 CFR 51.308(i)(3)
requires states, in developing their implementation plans, to include a
description of how they addressed FLMs' comments. Section 40 CFR
51.308(i)(4) requires that the regional haze SIP revision provide
procedures for continuing consultation between the state and FLMs
regarding the state's visibility protection program.
2. State Assessment: As required by CAA section 169A(d), Tennessee
consulted with the FLMs prior to opening the State public comment
period \94\ on its proposed haze plan and included a summary of the
conclusions and recommendations of the FLMs in the proposed plan dated
July 2, 2021. The conclusions and recommendations of the FLMs on the
proposed plan are included in the Haze Plan in Section 10.4 and
Appendix H. \95\
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\94\ TDEC provided a draft plan to the FLMs on July 2, 2021.
\95\ The consultation did not occur in person as stated in the
CAA due to the convenience and efficiency of using email, phone
calls, and video meetings.
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With respect to 40 CFR 51.308(i)(2), TDEC offered to the three FLM
agencies the opportunity to consult on the July 2, 2021, draft
Tennessee Haze Plan. Additionally, TDEC shared with the FLMs the
October 22, 2021, Prehearing Tennessee Haze Plan issued for state
public notice and comment with a public hearing held December 1, 2021,
with the close of the comment period on December 10, 2021. A summary of
this consultation process is discussed in Appendix H of the Haze Plan
(FLM comments received) with supporting information in Appendix H-1a
through H-1e and Appendix F.\96\ Appendix H provides a summary of the
FLM comments received on the draft and prehearing haze plans. TDEC
received comments from the NPS and USFS. No comments were received from
the FWS.
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\96\ Appendices F-3a-3n include VISTAS consultation outreach
with stakeholders, including the FLMs. (See, in particular,
Appendices F-3b, F-3c, F-3d, and F-3j).
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To address 40 CFR 51.308(i)(3), TDEC provided responses to NPS and
USFS comments in Section 10.4 and Appendix I of the Haze Plan.
With respect to 40 CFR 51.308(i)(4), Tennessee updated its existing
procedures for continuing consultation with the FLMs, including annual
discussions with a review of the most recent IMPROVE monitoring data.
Records of annual consultations and progress report consultations will
be maintained in TDEC's regional haze files.
3. EPA Evaluation: EPA proposes to find that Tennessee addressed
all FLM consultation requirements in the CAA and RHR. With respect to
CAA section 169A(d), Tennessee consulted with the FLMs prior to the
State's public comment period and included a summary of the conclusions
and recommendations of the FLMs in the
[[Page 40294]]
proposed plan issued for public review.\97\
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\97\ A description of Tennessee's responses to FLM comments can
be found in Section 10.4 and Appendix H of the Haze Plan.
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Tennessee fully addressed the requirement for FLM consultation
under 40 CFR 51.308(i)(2) because the State offered the draft Tennessee
Haze Plan on July 2, 2021. EPA proposes to find that Tennessee has met
its requirements under 40 CFR 51.308(i)(2) to consult with the FLMs on
its Haze Plan for the second planning period.
EPA proposes to find that Tennessee satisfied 40 CFR 51.308(i)(3)
by providing responses to the FLM comments in Section 10.4 of the Haze
Plan.
EPA proposes to find that Tennessee satisfied 40 CFR 51.308(i)(4)
by establishing in its Haze Plan continuing consultation procedures as
summarized above.
V. Other Measures Proposed for Incorporation Into Tennessee's SIP
On February 9, 2023, Tennessee submitted a SIP revision regarding
the SO<INF>2</INF> attainment demonstration for Sullivan County, which
provides source-specific SO<INF>2</INF> emission limits and associated
compliance parameters for incorporation into Tennessee's SIP. This
submittal has been referred to throughout this Notice as the ``2023
Plan.'' On December 20, 2024, Tennessee submitted a letter to EPA
asking the Agency to incorporate certain permit conditions from the
2023 Plan to generally strengthen Tennessee's SIP, as detailed below.
EPA is proposing to incorporate these SO<INF>2</INF> limits and
associated monitoring, recordkeeping, and reporting conditions into
Tennessee's SIP as a SIP strengthening measure. Specifically, EPA is
proposing to adopt into Tennessee's SIP the combined 30-day rolling
average SO<INF>2</INF> emission limit of 1,248 lb/hr for Eastman
Boilers 18 through 24, 30, and 31 contained within Condition 1 of
Tennessee Operating Permit Number 080222 (State effective March 1,
2023). EPA is further proposing to adopt into Tennessee's SIP
supporting monitoring, recordkeeping, and reporting requirements for
this 1,248 lb/hr SO<INF>2</INF> limit contained in Condition 3 and
Attachment A of Tennessee Operating Permit Number 080222. EPA is also
proposing to adopt into Tennessee's SIP Condition 2 of Tennessee
Operating Permit Number 080222 (State effective March 1, 2023), which
contains a requirement to operate DSI at Boilers 23 and 24.
Tennessee has also requested that EPA incorporate into Tennessee's
SIP the 317 lb/hr and 293 lb/hr (30-day rolling average) SO<INF>2</INF>
emission limits for Eastman Boilers 30 and 31, respectively,
incorporated into Eastman's current title V Operating Permit 576501
(State effective October 1, 2021), along with supporting monitoring,
recordkeeping, and reporting requirements.\98\ Collectively, these
requirements are contained within conditions E3-8, E3-9, E3-20, and
Attachment 3 of this permit. These emission limits and the associated
monitoring, recordkeeping, and reporting requirements are based upon
existing measures to reduce SO<INF>2</INF> emissions from these
boilers, including the operation of a DSI at Boilers 23 and 24, an SDA
and electrostatic precipitator at Boiler 30, and an SDA and fabric
filter at Boiler 31.
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\98\ Title V Permit No. 576501 is included in the docket for
this proposed action.
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While EPA is proposing to incorporate these permit conditions into
Tennessee's SIP as a SIP strengthening measure, EPA is not proposing to
approve, disapprove, or otherwise take action on other portions of the
2023 Plan. Any determination regarding approvability of the attainment
demonstration--including the approvability of the permit conditions
proposed for incorporation into the SIP in this Notice of Proposed
Rulemaking for the specific purpose of that attainment demonstration--
would be subject to a separate rulemaking.
VI. Incorporation by Reference
In this document, EPA is proposing to include in a final EPA rule
regulatory text that includes incorporation by reference. In accordance
with the requirements of 1 CFR 51.5, and as discussed above in this
preamble, EPA is proposing to incorporate by reference into Tennessee's
SIP Operating Permit Number 079592 (State effective February 9, 2022)
for Eastman. EPA is also proposing to incorporate by reference into
Tennessee's SIP that portion of Condition 1 of Tennessee Operating
Permit Number 080222 (State effective March 1, 2023) containing the 30-
day rolling average SO<INF>2</INF> emission limit of 1,248 lb/hr for
Eastman Boilers 18 through 24, 30, and 31; all of Condition 2 of
Tennessee Operating Permit Number 080222 (State effective March 1,
2023); that portion of Condition 3 of Tennessee Operating Permit Number
080222 (State effective March 1, 2023) containing the supporting
monitoring, recordkeeping, and reporting requirements for the 1,248 lb/
hr SO<INF>2</INF> limit; and Attachment A to Tennessee Operating Permit
Number 080222 (State effective March 1, 2023). EPA is further proposing
to incorporate by reference into Tennessee's SIP Conditions E3-8 and
E3-9 of Tennessee Operating Permit Number 576501 (State effective
October 1, 2021), which include the 317 lb/hr and 293 lb/hr
SO<INF>2</INF> limits applicable to Boilers 30 and 31; Condition E3-20;
and Attachment 3 to this permit. EPA has made, and will continue to
make, these materials generally available through <a href="http://www.regulations.gov">www.regulations.gov</a>
and at the EPA Region 4 Office (please contact the person identified in
the For Further Information Contact section of this preamble for more
information).
VII. Proposed Action
For the reasons stated herein, EPA is proposing to approve
Tennessee's February 23, 2022, SIP submission. EPA is also proposing to
incorporate into Tennessee's SIP, as SIP strengthening measures, those
portions of Tennessee's February 9, 2023, SIP submission discussed
above in Section VI (entitled Incorporation by Reference) of this
Notice. EPA is not proposing to approve, disapprove, or otherwise take
action on any other aspects of Tennessee's February 9, 2023, submittal
in this Notice.
VIII. Statutory and Executive Order Reviews
Under the CAA, the Administrator is required to approve a SIP
submission that complies with the provisions of the CAA and applicable
Federal regulations. See 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in
reviewing SIP submissions, EPA's role is to approve state choices,
provided that they meet the criteria of the CAA. Accordingly, this
proposed action merely proposes to approve state law as meeting Federal
requirements and does not impose additional requirements beyond those
imposed by state law. For that reason, this proposed action:
<bullet> Is not a significant regulatory action subject to review
by the Office of Management and Budget under Executive Order 12866 (58
FR 51735, October 4, 1993);
<bullet> Is not subject to Executive Order 14192 (90 FR 9065,
February 6, 2025) because SIP actions are exempt from review under
Executive Order 12866;
<bullet> Does not impose an information collection burden under the
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
<bullet> Is certified as not having a significant economic impact
on a substantial number of small entities
[[Page 40295]]
under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);
<bullet> Does not contain any unfunded mandate or significantly or
uniquely affect small governments, as described in the Unfunded
Mandates Reform Act of 1995 (Pub. L. 104-4);
<bullet> Does not have federalism implications as specified in
Executive Order 13132 (64 FR 43255, August 10, 1999);
<bullet> Is not subject to Executive Order 13045 (62 FR 19885,
April 23, 1997) because it approves a state program;
<bullet> Is not a significant regulatory action subject to
Executive Order 13211 (66 FR 28355, May 22, 2001); and
<bullet> Is not subject to requirements of section 12(d) of the
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272
note) because application of those requirements would be inconsistent
with the CAA.
In addition, the SIP is not approved to apply on any Indian
reservation land or in any other area where EPA or an Indian Tribe has
demonstrated that a Tribe has jurisdiction. In those areas of Indian
country, the rule does not have Tribal implications and will not impose
substantial direct costs on Tribal governments or preempt Tribal law as
specified by Executive Order 13175 (65 FR 67249, November 9, 2000).
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Incorporation by
reference, Nitrogen dioxide, Particulate matter, Sulfur oxides.
Authority: 42 U.S.C. 7401 et seq.
Dated: July 24, 2025.
Kevin McOmber,
Regional Administrator, Region 4.
[FR Doc. 2025-15748 Filed 8-18-25; 8:45 am]
BILLING CODE 6560-50-P
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This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.