Document ID: EPA-R06-OAR-2015-0189-0292
Agency: epa
Document Type: Proposed Rule
Title: AR020.0292 Air Quality State Implementation Plans; Approvals and Promulgations: Arkansas; Regional Haze and Visibility Transport State Implementation Plan Revisions and Withdrawal of Federal Implementation Plan, Proposed rule. 23 pages
Posted Date: 2020-03-16T04:00Z

[Federal Register Volume 85, Number 51 (Monday, March 16, 2020)]
[Proposed Rules]
[Pages 14847-14869]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-05106]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R06-OAR-2015-0189; FRL-10006-02-Region 6]

Air Plan Approval; Arkansas; Arkansas Regional Haze and 
Visibility Transport State Implementation Plan Revisions and Withdrawal 
of Federal Implementation Plan

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: Pursuant to the Clean Air Act (CAA or the Act), the 
Environmental Protection Agency (EPA) is proposing to approve a 
revision to the Arkansas State Implementation Plan (SIP) submitted by 
the State of Arkansas through the Arkansas Division of Environmental 
Quality (ADEQ) on August 13, 2019. The SIP submittal addresses 
requirements of the Act and the Regional Haze Rule for visibility 
protection in mandatory Class I Federal areas (Class I areas) for the 
first implementation period. The EPA is proposing to approve an 
alternative measure to best available retrofit technology (BART) for 
sulfur dioxide (SO2), particulate matter (PM), and nitrogen 
oxide (NOX) at the Domtar Ashdown Mill and elements of the 
SIP submittal that relate to these BART requirements at this facility. 
In addition, we are proposing to approve the withdrawal from the SIP 
the previously approved PM10 BART limit and the federal 
implementation plan (FIP) provisions for the Domtar Ashdown Mill. The 
EPA is also concurrently proposing to approve Arkansas' interstate 
visibility transport provisions from the August 10, 2018, regional haze 
SIP submittal as supplemented by the visibility transport provisions in 
the October 4, 2019, interstate transport SIP submittal, which covers 
the following national ambient air quality standards (NAAQS): The 2006 
24-hour fine particulate matter (PM2.5) NAAQS; the 2012 
annual PM2.5 NAAQS; the 2008 and 2015 eight-hour ozone 
(O3) NAAQS; the 2010 one-hour nitrogen dioxide 
(NO2) NAAQS; and the 2010 one-hour SO2 NAAQS.

DATES: Written comments must be received on or before April 15, 2020.

ADDRESSES: Submit your comments, identified by Docket No. EPA-R06-OAR-
2015-0189, at http://www.regulations.gov or via email to 
R6AIR_ARHaze@epa.gov. Follow the online instructions for submitting 
comments. Once submitted, comments cannot be edited or removed from 
Regulations.gov. The EPA may publish any comment received to its public 
docket. Do not submit any information electronically that is considered 
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 with multimedia 
submissions and should include all discussion points desired. The EPA 
will generally not consider comments or their contents located outside 
of the primary submission (i.e., on the web, cloud, or other file 
sharing systems). For additional submission methods, please contact 
James E. Grady, (214) 665-6745, grady.james@epa.gov. For the full EPA 
public comment policy, information about CBI or multimedia submissions, 
and general guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.
    Docket: The index to the docket for this action is available 
electronically at www.regulations.gov and in hard copy at the EPA 
Region 6, 1201 Elm Street, Suite 500, Dallas, Texas 75270-2102. While 
all documents in the docket are listed in the index, some information 
may be publicly available only at the hard copy location (e.g., 
copyrighted material), and some may not be publicly available at either 
location (e.g., CBI).

FOR FURTHER INFORMATION CONTACT: James E. Grady, EPA Region 6 Office, 
Regional Haze and SO2 Section, 1201 Elm Street, Suite 500, 
Dallas, TX 72570, 214-665-6745; grady.james@epa.gov. To inspect the 
hard copy materials, please schedule an appointment with Mr. Grady or 
Mr. Bill Deese at 214-665-7253.

SUPPLEMENTARY INFORMATION: Throughout this document ``we,'' ``us,'' or 
``our'' mean ``the EPA.''

Table of Contents

I. Background
    A. Regional Haze Principles
    B. Requirements of the CAA and the EPA's Regional Haze Rule
    C. BART Requirements
    D. BART Alternative Requirements
    E. Long-Term Strategy and Reasonable Progress Requirements
    F. Previous Actions on Arkansas Regional Haze

[[Page 14848]]

    G. Arkansas Regional Haze Phase III SIP Submittal
    H. Arkansas Visibility Transport
II. Evaluation of the Arkansas Regional Haze Phase III SIP Submittal
    A. Summary of Arkansas' BART Alternative for Domtar Ashdown Mill
    B. Demonstration That BART Alternative Achieves Greater 
Reasonable Progress
    1. List All BART-Eligible Sources Within the State
    2. List All BART-Eligible Sources and Source Categories Covered 
by the Alternative Program
    3. Analysis of BART and Associated Emission Reductions
    4. Analysis of Projected Emission Reductions Achievable Through 
BART Alternative
    5. Determination That Alternative Achieves Greater Reasonable 
Progress than BART
    C. Requirement That Emission Reductions Take Place During the 
Period of the First Long-Term Strategy
    D. Demonstration That Emission Reductions From Alternative 
Measure Will Be Surplus
    E. Implementation of the BART Alternative Through Permit 
Conditions
    F. EPA's Conclusion on Arkansas' BART Alternative Determination 
for Domtar
    G. Consultation With States and Federal Land Managers
III. Evaluation of Arkansas' Long-Term Strategy Provisions for 
Domtar Ashdown Mill
IV. Evaluation of Reasonable Progress Requirements for Domtar 
Ashdown Mill
V. Evaluation of Arkansas Visibility Transport
    A. Fully-Approved Regional Haze SIP To Meet Visibility Transport 
Requirement
    B. Alternative Demonstration To Meet Visibility Transport 
Requirement
    C. EPA's Conclusion on Arkansas Visibility Transport
VI. Evaluation of CAA Section 110(1)
VII. Proposed Action
    A. Arkansas Regional Haze Phase III SIP Submittal
    B. FIP Withdrawal
    C. Arkansas Visibility Transport
    D. CAA Section 110(1)
VIII. Incorporation by Reference
IX. Statutory and Executive Order Reviews

I. Background

A. Regional Haze Principles

    Regional haze is visibility impairment that is produced by a 
multitude of sources and activities that are located across a broad 
geographic area and emit fine particulates (PM2.5) \1\ into 
the air. Fine particulates which cause haze are sulfates 
(SO42-), nitrates 
(NO3-), organic carbon (OC), elemental carbon 
(EC), and soil dust.\2\ PM2.5 precursors consist of 
SO2, NOX, volatile organic compounds (VOCs), and 
in some cases, ammonia (NH3). Airborne PM2.5 can 
scatter and absorb the incident light and, therefore, lead to 
atmospheric opacity and horizontal visibility degradation. Regional 
haze limits visual distance and reduces color, clarity, and contrast of 
view. PM2.5 can cause serious adverse health effects and 
mortality in humans. It also contributes to environmental effects such 
as acid deposition and eutrophication. Emissions that affect visibility 
include a wide variety of natural and man-made sources. Natural sources 
can include windblown dust and soot from wildfires. Man-made sources 
can include major and minor stationary sources, mobile sources, and 
area sources. Reducing PM2.5 and its precursor gases in the 
atmosphere is an effective method of improving visibility.
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    \1\ Fine particles are less than or equal to 2.5 microns 
([micro]m) in diameter and usually form secondary in nature 
indirectly from other sources. Particles less than or equal to 10 
[micro]m in diameter are referred to as PM10. Particles 
greater than PM2.5 but less than PM10 are 
referred to as coarse mass. Coarse mass can contribute to light 
extinction as well and is made up of primary particles directly 
emitted into the air. Fine particles tend to be man-made, while 
coarse particles tend to have a natural origin. Coarse mass settles 
out from the air more rapidly than fine particles and usually will 
be found relatively close to emission sources. Fine particles can be 
transported long distances by wind and can be found in the air 
thousands of miles from where they were formed.
    \2\ Organic carbon can be emitted directly as particles or 
formed through reactions involving gaseous emissions. Elemental 
carbon, in contrast to organic carbon, is exclusively of primary 
origin and emitted by the incomplete combustion of carbon-based 
fuels. Elemental carbon particles are especially prevalent in diesel 
exhaust and smoke from wild and prescribed fires.
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    Data from the existing visibility monitoring network, ``Interagency 
Monitoring of Protected Visual Environments'' (IMPROVE), shows that 
visibility impairment caused by air pollution occurs virtually all of 
the time at most national parks and wilderness areas. In 1999, the 
average visual range \3\ in many mandatory Class I Federal areas \4\ in 
the western United States was 100-150 kilometers (km), or about one-
half to two-thirds of the visual range that would exist under estimated 
natural conditions.\5\ In most of the eastern Class I areas of the 
United States, the average visual range was less than 30 km, or about 
one-fifth of the visual range that would exist under estimated natural 
conditions. Since the promulgation of the original Regional Haze Rule 
in 1999, CAA programs have reduced emissions of haze-causing pollution, 
lessening visibility impairment and resulting in improved average 
visual ranges.\6\
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    \3\ Visual range is the greatest distance, in km or miles, at 
which a dark object can be viewed against the sky by a typical 
observer.
    \4\ 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. The EPA, in consultation with the 
Department of Interior, promulgated a list of 156 areas where 
visibility was identified as an important value. The extent of a 
mandatory Class I area includes subsequent changes in boundaries, 
such as park expansions. Although states and tribes may designate 
additional areas as Class I, the requirements of the visibility 
program set forth in the CAA applies only to mandatory Class I 
Federal areas. Each mandatory Class I Federal area is the 
responsibility of a Federal Land Manager (FLM). When the term 
``Class I area'' is used in this action, it means ``mandatory Class 
I Federal areas.'' See 44 FR 69122 (November 30, 1979) and CAA 
Sections 162(a), 169A, and 302(i).
    \5\ 64 FR 35714, 35715 (July 1, 1999).
    \6\ An interactive story map depicting efforts and recent 
progress by the EPA and states to improve visibility at national 
parks and wilderness areas may be visited at: http://arcg.is/29tAbS3.
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B. Requirements of the CAA and the EPA's Regional Haze Rule

    In section 169A, enacted as part of the 1977 CAA Amendments, 
Congress created a program for protecting visibility in the nation's 
national parks and wilderness areas. This section of the CAA 
establishes as a national goal the prevention of any future, and the 
remedying of any existing, visibility impairment in mandatory Class I 
Federal areas where impairment results from manmade air pollution. 
Congress added section 169B to the CAA in 1990 that added visibility 
protection provisions, and the EPA promulgated final regulations 
addressing regional haze as part of the 1999 Regional Haze Rule, which 
was most recently updated in 2017.\7\ The Regional Haze Rule revised 
the existing 1980 visibility regulations and established a more 
comprehensive visibility protection program for Class I areas. The 
requirements for regional haze, found at 40 CFR 51.308 and 51.309, are 
included in the EPA's broader visibility protection regulations at 40 
CFR 51.300-309. The regional haze regulations require states to 
demonstrate reasonable progress toward meeting the national goal of a 
return to natural visibility conditions for Class I areas by 2064. The 
CAA requirement in section 169A(b)(2) to submit a regional haze SIP 
applies to all fifty states, the District of Columbia, and the Virgin 
Islands. States were required to submit the first implementation plan 
addressing visibility impairment caused by regional haze no later than 
December 17, 2007.\8\
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    \7\ See the July 1, 1999 Regional Haze Rule final action (64 FR 
35714), as amended on July 6, 2005 (70 FR 39156), October 13, 2006 
(71 FR 60631), June 7, 2012 (77 FR 33656) and on January 10, 2017 
(82 FR 3079).
    \8\ See 40 CFR 51.308(b). Also, under 40 CFR 51.308(f)-(i), the 
EPA requires subsequent updates to the regional haze SIPs for each 
implementation period. The next update for the second implementation 
period is due by July 31, 2021.

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[[Page 14849]]

C. BART Requirements

    Section 169A(b)(2)(A) of the CAA directs states to evaluate the use 
of BART controls at certain categories of existing major stationary 
sources built between 1962 and 1977.\9\ Under 40 CFR 51.308(e)(1)(ii), 
any BART-eligible source \10\ that is reasonably anticipated to cause 
or contribute to visibility impairment in a Class I area is classified 
as subject-to-BART.\11\ States are directed to conduct BART 
determinations for each source classified as subject-to-BART. These 
large, often under-controlled, older stationary sources are required to 
procure, install, and operate BART controls to address visibility 
impacts. The determination must be based on an analysis of the best 
system of continuous emission control technology available and 
associated emission reductions achievable. States are required to 
identify the level of control representing BART after considering the 
five statutory factors set out in CAA section 169A(g)(2).\12\ States 
must establish emission limits, a schedule of compliance, and other 
measures consistent with the BART determination process for each source 
subject-to-BART.
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    \9\ See 42 U.S.C. 7491(g)(7), which lists the 26 source 
categories of major stationary sources potentially subject-to-BART.
    \10\ BART-eligible sources are those sources that fall within 
one of 26 source categories that began operation on or after August 
7, 1962, and were in existence on August 7, 1977, with potential 
emissions greater than 250 tons per year (tpy). (See 40 CFR 51 
Appendix Y, section II).
    \11\ Under the BART Guidelines, states may select a visibility 
impact threshold, measured in deciviews (dv), below which a BART-
eligible source would not be expected to cause or contribute to 
visibility impairment in any Class I area. The State must document 
this threshold in the SIP and specify the basis for its selection of 
that value. Any source with visibility impacts that model above the 
threshold value would be subject to a BART determination review. The 
BART Guidelines acknowledge varying circumstances affecting 
different Class I areas. States should consider the number of 
emission sources affecting the Class I areas at issue and the 
magnitude of the individual sources' impacts. Any visibility impact 
threshold set by the state should not be higher than 0.5 dv. (See 40 
CFR part 51, Appendix Y, section III.A.1).
    \12\ The State must take into consideration the five statutory 
factors: (1) Costs of compliance, (2) the energy and non-air quality 
environmental impacts, (3) any existing control technology present 
at the source, (4) the remaining useful life of the source, and (5) 
the degree of visibility improvement.
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D. BART Alternative Requirements

    A State may opt to implement or require participation in an 
emissions trading program or other alternative measure rather than 
require sources subject-to-BART to install, operate, and maintain BART. 
Such an emissions trading program or other alternative measure must 
achieve greater reasonable progress than would be achieved through the 
installation and operation of BART. In order to demonstrate that the 
alternative program achieves greater reasonable progress than source-
specific BART, a state must demonstrate that its SIP meets the 
requirements in 40 CFR 51.308(e)(2)(i) to (iv).\13\ The state must 
conduct an analysis of the best system of continuous emission control 
technology available and the associated reductions for each source 
subject-to-BART covered by the alternative program.
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    \13\ 40 CFR 51.308(e)(2)(ii) is reserved. Under 40 CFR 
51.308(e)(2)(v), ``At the State's option, a provision that the 
emissions trading program or other alternative measure may include a 
geographic enhancement to the program to address the requirement 
under 40 CFR 51.302(b) or (c) related to reasonably attributable 
impairment from the pollutants covered under the emissions trading 
program or other alternative measure.''
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    Pursuant to 40 CFR 51.308(e)(2)(i)(E), the state must provide a 
determination under 40 CFR 51.308(e)(3) or otherwise based on ``clear 
weight of evidence'' that the alternative measure achieves greater 
reasonable progress than BART. 40 CFR 51.308(e)(3) provides two 
specific tests applicable under specific circumstances for determining 
whether the alternative measure achieves greater reasonable progress 
than BART. Under the first test, if the distribution of emissions is 
not substantially different than under BART, and the alternative 
measure results in greater emission reductions, then the alternative 
measure may be deemed to achieve greater reasonable progress. Under the 
second test, if the distribution of emissions is significantly 
different, then the State must conduct dispersion modeling to determine 
the difference in visibility between BART and the alternative measure 
for each impacted Class I area, for the twenty percent best and worst 
days. The modeling would demonstrate greater reasonable progress if 
both of the following two criteria are met: (i) Visibility does not 
decline in any Class I area, and (ii) there is an overall improvement 
in visibility, determined by comparing the average difference between 
BART and the alternative over all affected Class I areas.
    Alternatively, under 40 CFR 51.308(e)(2)(i)(E), states may show 
based on ``clear weight of evidence'' that the alternative achieves 
greater reasonable progress than would be achieved through the 
installation and operation of BART at the covered sources. As stated in 
the EPA's revisions to the Regional Haze Rule governing alternatives to 
source-specific BART determinations, weight of evidence demonstrations 
attempt to make use of all available information and data which can 
inform a decision while recognizing the relative strengths and 
weaknesses of that information in arriving at the soundest decision 
possible.\14\ This array of information and other relevant data must be 
of sufficient quality to inform the comparison of visibility impacts 
between BART and the alternative. A weight of evidence comparison may 
be warranted when there is confidence that the difference in visibility 
impacts between BART and the alternative scenarios are expected to be 
large enough to show that an alternative is better than BART. The EPA 
will carefully consider this evidence in evaluating any SIPs submitted 
by States employing such an approach.
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    \14\ See 71 FR 60612, 60622 (October 13, 2006). Factors which 
can be used in a weight of evidence determination in this context 
may include, but not be limited to, future projected emissions 
levels under the alternative as compared to under BART; future 
projected visibility conditions under the two scenarios; the 
geographic distribution of sources likely to reduce or increase 
emissions under the alternative as compared to BART sources; 
monitoring data and emissions inventories; and sensitivity analyses 
of any models used.
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    Finally, under 40 CFR 51.308(e)(2)(iii) and (iv), all emission 
reductions for the alternative program must take place during the 
period of the first long-term strategy for regional haze, and all the 
emission reductions resulting from the alternative program must be 
surplus to those reductions resulting from measures adopted to meet 
requirements of the CAA as of the baseline date of the SIP. These 
requirements are discussed in more detail in subsequent sections of 
this proposed action.

E. Long-Term Strategy and Reasonable Progress Requirements

    In addition to BART requirements, 40 CFR 51.308(d)(3)(i to iv) 
requires each state to include in its SIP a long-term strategy for the 
planning period that addresses regional haze visibility impairment for 
each Class I area located within the state and outside the state that 
may be affected by emissions generated from within the state. The long-
term strategy is the vehicle for ensuring continuing reasonable 
progress toward achieving natural visibility conditions. It is a 
compilation of all control measures in the SIP that a state will use 
during the implementation period to meet the applicable reasonable 
progress goals (RPGs) established under 40 CFR 51.308(d)(1) for each 
Class I area.\15\ The RPGs established by the

[[Page 14850]]

State provide an assessment of the visibility improvement anticipated 
to result for that planning period.\16\ Section 51.308(d)(3)(v) 
requires that a state consider certain minimum factors (the long-term 
strategy factors) in developing its long-term strategy for each Class I 
area.\17\ States have significant flexibility in establishing RPGs but 
must determine whether additional measures beyond BART and other 
controls are needed for reasonable progress during the first planning 
period based on a consideration of the following four reasonable 
progress factors set out in section 169A(g)(1) of the CAA: (1) The 
costs of compliance; (2) the time necessary for compliance; (3) the 
energy and non-air quality environmental impacts of compliance; and (4) 
the remaining useful life of any potentially affected sources.\18\ 
States must demonstrate in their regional haze SIPs how these factors 
are considered when selecting their long-term strategies and associated 
RPGs for each applicable Class I area. We commonly refer to this as the 
``reasonable progress analysis'' or ``four-factor analysis.''
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    \15\ See 40 CFR 51.308(d)(3)(i to iv). For the first planning 
period, contributing and impacted states must develop coordinated 
emission management strategies. Impacted states must demonstrate 
that they have included all measures necessary in their SIPs to 
obtain their share of emission reductions needed to meet the RPGs 
for a Class I area. States must document the technical basis that 
they relied upon to determine the apportionment of emission 
reduction obligations necessary and identify the baseline emissions 
inventory on which their strategies are based. States must also 
identify all anthropogenic sources of visibility impairment 
considered in developing the strategy, such as major and minor 
stationary sources, mobile sources, and area sources.
    \16\ The process for setting RPGs is as follows: (1) Identify 
sources that impact visibility; (2) evaluate potential controls 
based on consideration of the four reasonable progress factors; (3) 
project the visibility conditions based on implementation of on-the-
books and additional selected controls; (4) compare the projected 
visibility conditions to the uniform rate of progress (URP) needed 
to attain natural visibility conditions by year 2064 for each Class 
I area; (5) determine an RPG for each Class I area based on this 
analysis that will improve the visibility at or beyond the URP on 
the most impaired days and ensure no degradation for the least 
impaired days. The Regional Haze Rule allows for the selection of an 
RPG at a given Class I area that provides for a slower rate of 
improvement than the URP for that area, but in that case a state 
must demonstrate that the URP is not reasonable and that the RPG 
selected is. (see 40 CFR 51.308(d)(1)(ii).
    \17\ These factors are: (1) Emission reductions due to ongoing 
air pollution control programs, including measures to address 
reasonably attributable visibility impairment (RAVI); (2) measures 
to mitigate the impacts of construction activities; (3) emissions 
limitations and schedules for compliance to achieve the reasonable 
progress goal; (4) source retirement and replacement schedules; (5) 
smoke management techniques for agricultural and forestry management 
purposes including plans as currently exist within the state for 
these purposes; (6) enforceability of emissions limitations and 
control measures; and (7) the anticipated net effect on visibility 
due to projected changes in point, area, and mobile source emissions 
over the period addressed by the long-term strategy.
    \18\ Guidance for Setting Reasonable Progress Goals under the 
Regional Haze Program, June 1, 2007, memorandum from William L. 
Wehrum, Acting Assistant Administrator for Air and Radiation, to the 
EPA Regional Administrators, EPA Regions 1-10 (pp.4-2, 5-1).
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F. Previous Actions on Arkansas Regional Haze

    The State of Arkansas submitted a regional haze SIP on September 9, 
2008, intended to address the requirements of the first regional haze 
implementation period. On August 3, 2010, the State submitted a SIP 
revision with mostly non-substantive changes that addressed Arkansas 
Pollution Control and Ecology Commission (APCEC) Regulation 19, Chapter 
15.\19\ On September 27, 2011, the State submitted a supplemental 
letter that clarified several aspects of the 2008 submittal. The EPA 
collectively refers to the original 2008 submittal, the supplemental 
letter, and the 2010 revision together as the 2008 Arkansas Regional 
Haze SIP. On March 12, 2012, the EPA partially approved and partially 
disapproved the 2008 Arkansas Regional Haze SIP.\20\ Specifically, the 
EPA disapproved certain BART compliance dates; the State's 
identification of certain BART-eligible sources and subject-to-BART 
sources; certain BART determinations for NOX, 
SO2, and PM10; the State's reasonable progress 
analysis; and a portion of the State's long-term strategy. The 
remaining provisions of the 2008 Arkansas Regional Haze SIP were 
approved. The final partial disapproval started a two-year FIP clock 
that obligated the EPA to either approve a SIP revision and/or 
promulgate a FIP to address the disapproved portions of the action.\21\ 
Because a SIP revision addressing the deficiencies was not approved and 
the FIP clock expired in April 2014, the EPA promulgated a FIP (the 
Arkansas Regional Haze FIP) on September 27, 2016, to address the 
disapproved portions of the 2008 Arkansas Regional Haze SIP.\22\ Among 
other things, the FIP established SO2, NOX, and 
PM10 emission limits under the BART requirements for nine 
units at six facilities: Arkansas Electric Cooperative Corporation 
(AECC) Carl E. Bailey Plant Unit 1 Boiler; AECC John L. McClellan Plant 
Unit 1 Boiler; American Electric Power/Southwestern Electric Power 
Company (AEP/SWEPCO) Flint Creek Plant Boiler No. 1; Entergy \23\ Lake 
Catherine Plant Unit 4 Boiler; Entergy White Bluff Plant Units 1 and 2 
Boilers and the Auxiliary Boiler; and the Domtar Ashdown Mill Power 
Boilers No. 1 and 2. The FIP also established SO2 and 
NOX emission limits under the reasonable progress 
requirements for the Entergy Independence Plant Units 1 and 2.
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    \19\ The September 9, 2008 SIP submittal included APCEC 
Regulation 19, Chapter 15, which is the state regulation that 
identified the BART-eligible and subject-to-BART sources in Arkansas 
and established BART emission limits for subject-to-BART sources. 
The August 3, 2010 SIP revision did not revise Arkansas' list of 
BART-eligible and subject-to-BART sources or revise any of the BART 
requirements for affected sources. Instead, it included mostly non-
substantive revisions to the state regulation.
    \20\ See the final action on (March 12, 2012) (77 FR 14604).
    \21\ Under CAA section 110(c), the EPA is required to promulgate 
a FIP within two years of the effective date of a finding that a 
state has failed to make a required SIP submission or has made an 
incomplete submission, or of the effective date that the EPA 
disapproves a SIP in whole or in part. The FIP requirement is 
terminated only if a state submits a SIP, and the EPA approves that 
SIP as meeting applicable CAA requirements before promulgating a 
FIP.
    \22\ See FIP final action on September 27,2016 (81 FR 66332) as 
corrected on October 4, 2016 (81 FR 68319).
    \23\ ``Entergy'' collectively means Entergy Arkansas Inc., 
Entergy Mississippi Inc., and Entergy Power LLC.
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    Following petitions for reconsideration \24\ submitted by the 
State, industry, and ratepayers, on April 25, 2017, the EPA issued a 
partial administrative stay of the effectiveness of the FIP for ninety 
days.\25\ During that period, Arkansas started to address the 
disapproved portions of its regional haze SIP through several phases of 
SIP revisions. On July 12, 2017, the State submitted its proposed Phase 
I SIP submittal (the Arkansas Regional Haze NOX SIP 
revision) to address NOX BART requirements for all electric 
generating units (EGUs) and the reasonable progress requirements with 
respect to NOX. These NOX provisions were 
previously disapproved by the EPA in our 2012 final action on the 2008 
Arkansas Regional Haze SIP. The Arkansas Regional Haze NOX 
SIP submittal replaced all source-specific NOX BART 
determinations for EGUs established in the FIP with reliance upon the 
Cross-State Air Pollution Rule (CSAPR) emissions trading program for 
O3 season NOX as an alternative to NOX 
BART. The SIP submittal addressed the NOX BART requirements 
for Bailey Unit 1, McClellan Unit 1, Flint Creek Boiler No. 1, Lake 
Catherine Unit 4; White Bluff Units 1 and 2, and the Auxiliary Boiler. 
The revision did not address NOX BART for Domtar Ashdown 
Mill Power Boilers No. 1 and 2. On February 12, 2018, we took final 
action to approve the Arkansas Regional Haze

[[Page 14851]]

NOX SIP revision and to withdraw the corresponding 
NOX provisions of the FIP.\26\
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    \24\ Copies of the petitions for reconsideration and 
administrative stay submitted by the State of Arkansas; Entergy; 
Arkansas Electric Cooperative Corporation (AECC); and the Energy and 
Environmental Alliance of Arkansas (EEAA) are available in the 
docket of this action.
    \25\ See 82 FR 18994.
    \26\ See 82 FR 42627 (September 11, 2017) for the proposed 
approval. See also 83 FR 5915 and 83 FR 5927 (February 12, 2018) for 
the final action.
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    The State submitted its Phase II SIP revision (the Arkansas 
Regional Haze SO2 and PM SIP revision) on August 8, 2018, 
that addressed most of the remaining parts of the 2008 Arkansas 
Regional Haze SIP that were disapproved in the March 12, 2012, action. 
The August 8, 2018, SIP submittal was intended to replace the federal 
SO2 and PM10 BART determinations as well as the 
reasonable progress determinations established in the FIP with the 
State's own determinations. Specifically, the SIP revision addressed 
the applicable SO2 and PM10 BART requirements for 
Bailey Unit 1; SO2 and PM10 BART requirements for 
McClellan Unit 1; SO2 BART requirements for Flint Creek 
Boiler No. 1; SO2 BART requirements for White Bluff Units 1 
and 2; SO2, NOX, and PM10 BART 
requirements for the White Bluff Auxiliary Boiler; \27\ and included a 
requirement that Lake Catherine Unit 4 not burn fuel oil until 
SO2 and PM BART determinations for the fuel oil firing 
scenario are approved into the SIP by the EPA.\28\ The submittal 
addressed the reasonable progress requirements with respect to 
SO2 and PM10 emissions for Independence Units 1 
and 2 and all other sources in Arkansas. In addition, it established 
revised RPGs for Arkansas' two Class I areas and revised the State's 
long-term strategy provisions. The submittal did not address BART and 
associated long-term strategy requirements for Domtar Ashdown Mill 
Power Boilers No. 1 and 2, but they are addressed in this proposed 
action. On September 27, 2019, we took final action to approve a 
portion of the Arkansas Regional Haze SO2 and PM SIP 
revision and to withdraw the corresponding parts of the FIP.\29\ The 
August 8, 2018, SIP also contained a discussion of the interstate 
visibility transport provisions, as discussed in more detail in Section 
I.H.
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    \27\ The Arkansas Regional Haze SO2 and PM SIP 
revision established a new NOX emission limit of 32.2 
pounds per hour (pph) for the Auxiliary Boiler to satisfy 
NOX BART and replaced the SIP determination that we 
previously approved in our final action on the Arkansas Regional 
Haze NOX SIP revision. In the Arkansas Regional Haze 
NOX SIP revision, ADEQ incorrectly identified the 
Auxiliary Boiler as participating in the CSAPR trading program for 
O3 season NOX to satisfy the NOX 
BART requirements. The new source-specific NOX BART 
emission limit that we approved in our final action on the Arkansas 
Regional Haze SO2 and PM SIP revision corrected that 
error.
    \28\ The 2012 action disapproved SO2, NOX, 
and PM BART for the fuel oil firing scenario for the Entergy Lake 
Catherine Plant Unit 4, but a FIP BART determination was not 
established. Instead, the FIP included a requirement that Entergy 
not burn fuel oil at Lake Catherine Unit 4 until final EPA approval 
of BART determinations for SO2, NOX, and PM. 
In the Arkansas Regional Haze NOX SIP revision, Arkansas 
relied on participation in CSAPR for O3 season 
NOX to satisfy the NOX BART requirement for 
its subject-to-BART EGUs, including Lake Catherine Unit 4. When we 
took final action on the Arkansas Regional Haze NOX SIP 
revision, we also took final action to withdraw the FIP 
NOX emission limit for the natural gas firing scenario 
for Lake Catherine Unit 4. In the Arkansas Regional Haze 
SO2 and PM SIP revision, Entergy committed to not burn 
fuel oil at Lake Catherine Unit 4 until final EPA approval of BART 
for SO2 and PM. This commitment was made enforceable by 
the State through an Administrative Order that was adopted and 
incorporated in the Arkansas Regional Haze SO2 and PM SIP 
revision.
    \29\ See 83 FR 62204 (November 30, 2018) for proposed approval 
and 84 FR 51033 (September 27, 2019) for final approval. The 
Arkansas Regional Haze SO2 and PM SIP revision also 
addressed separate CAA requirements related to interstate visibility 
transport under CAA section 110(a)(2)(D)(i)(II), but we did not take 
action on that part of the submittal. We are incorporating by 
reference the visibility transport portion of the Arkansas Regional 
Haze SO2 and PM SIP revision in this proposed action.
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G. Arkansas Regional Haze Phase III SIP Submittal

    On August 13, 2019, ADEQ submitted the Arkansas Regional Haze Phase 
III SIP (Phase III SIP revision) which we are proposing to approve in 
this action. The submittal contains a BART alternative measure to 
address BART and the associated long-term strategy requirements for two 
subject-to-BART sources (Power Boilers No. 1 and 2) at the Domtar 
Ashdown paper mill located in Ashdown, Arkansas. Power Boiler No. 1 was 
first installed in 1967-1968 and is currently permitted to burn only 
natural gas.\30\ It is capable of burning a variety of other fuels too 
including bark, wood waste, tire-derived fuel (TDF), municipal yard 
waste, pelletized paper fuel, fuel-oil, and reprocessed fuel-oil but is 
not authorized to do so. It is equipped with a wet electrostatic 
precipitator (WESP) \31\ but the requirements to operate the WESP were 
removed since it is permitted to combust natural gas only. Power Boiler 
No. 1 has a design heat input rating of 580 million British Thermal 
units per hour (MMBtu/hr) and an average steam generation rate of 
approximately 120,000 pounds per hour (pph). Power Boiler No. 2 was 
installed in 1975 and is authorized to burn a variety of fuels 
including coal, petroleum coke, TDF, natural gas, wood waste, clean 
cellulosic biomass (e.g. bark, wood residuals, and other woody biomass 
materials), bark, and wood chips used to absorb oil spills. It is 
equipped with a traveling grate; \32\ a combustion air system that 
includes over-fire air; \33\ multi-clones for PM10 removal; 
\34\ and two venturi scrubbers in parallel for removal of 
SO2 and remaining particulates. Power Boiler No. 2 has a 
heat input rating of 820 MMBtu/hr and an average steam generation rate 
of approximately 600,000 pph.
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    \30\ Power Boiler No. 1 operates as natural gas only subject to 
the Gas 1 subcategory defined under 40 CFR 63.7575. See ADEQ Air 
Permit No. 0287-AOP-R22 (page 64) in the docket of this action.
    \31\ An electrostatic precipitator is an air pollution control 
device that functions by electrostatically charging particles in a 
gas stream that passes through collection plates with wires. The 
ionized particulate matter is attracted to and deposited on the 
plates as the cleaner air passes through. A wet electrostatic 
precipitator is designed to operate with water vapor saturated air 
streams to remove liquid droplets such as sulfuric acid.
    \32\ A traveling grate is a moving grate used to feed fuel to 
the boiler for combustion.
    \33\ Over-fire air typically recirculates a portion of the flue 
gas back to both the fuel-rich zone and the combustion zone to 
achieve complete burnout by encouraging the formation of nitrogen 
(N2) rather than NOX.
    \34\ A cyclone separator is an air pollution control device 
shaped like a conical tube that creates an air vortex as air moves 
through it causing larger particles (PM10) to settle as 
the cleaner air passes through. Multi-clones are a sequence of 
cyclone separators in parallel used to treat a higher volume of air. 
In this particular case, the cleaner air travels to the venturi 
scrubbers to remove the smaller remaining particles like 
PM2.5 and SO2.
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    ADEQ's original BART analyses and determinations (dated October 
2006 and March 2007) for Power Boilers No. 1 and 2 were included in the 
2008 Arkansas Regional Haze SIP.\35\ In our 2012 action, we approved 
ADEQ's identification of these two units as BART-eligible; ADEQ's 
determination that these units are subject-to-BART; and ADEQ's 
PM10 BART determination for Power Boiler No. 1.\36\ In that 
action, we also disapproved the SO2 and NOX BART 
determinations for Power Boiler No. 1; and the SO2, 
NOX, and PM10 BART determinations for Power 
Boiler No. 2. In the 2016 Arkansas Regional Haze FIP and its associated 
technical support document (TSD),\37\ the EPA promulgated 
SO2, NOX, and PM10 emission limits for 
these boilers. The FIP BART limits were based on

[[Page 14852]]

consideration of the 2006 and 2007 BART analyses, a revised BART 
analysis (dated May 2014),\38\ and additional information provided by 
Domtar for the disapproved BART determinations. On March 20, 2018, 
Domtar provided ADEQ with a proposed BART alternative based on changing 
boiler operations as part of the company's planned re-purposing and 
mill transformation from paper production to fluff pulp production. On 
September 5, 2018, Domtar further revised its BART alternative approach 
in response to additional boiler operation changes planned at the 
Ashdown Mill.\39\ In October 2018, ADEQ proposed a SIP revision that 
included Domtar's BART alternative approach to address the BART 
requirements for Power Boilers 1 and 2 at the Ashdown Mill.\40\
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    \35\ See ``Best Available Retrofit Technology Determination 
Domtar Industries Inc., Ashdown Mill (AFIN 41-00002),'' originally 
dated October 31, 2006 and revised on March 26, 2007, prepared by 
Trinity Consultants Inc. This was included as part of the Phase III 
submittal and included in the docket of this action.
    \36\ See the March 12, 2012 final action (77 FR 14604).
    \37\ See final FIP action on September 27, 2016 (81 FR 66332) as 
corrected on October 4, 2016 (81 FR 68319) and the associated TSD, 
``AR020.0002-00 TSD for EPA's Proposed Action on the Arkansas 
Regional Haze FIP'' in Docket No. EPA-R06-OAR-2015-0189 for the FIP 
BART analysis for SO2 and NOX for Power Boiler 
No. 1; and SO2, NOX, and PM10 for 
Power Boiler No. 2. This was included as part of the Phase III 
submittal and included in the docket of this action.
    \38\ See ``Supplemental BART Determination Information Domtar 
A.W. LLC, Ashdown Mill (AFIN 41-00002),'' originally dated June 28, 
2013 and revised on May 16, 2014, prepared by Trinity Consultants 
Inc. in conjunction with Domtar A.W. LLC. This was included as part 
of the Phase III SIP submittal and is included in the docket of this 
action.
    \39\ See section III.B of the Arkansas Regional Haze Phase III 
submittal and the associated September 4, 2018, ``Ashdown Mill BART 
Alternative TSD'' in the docket of this action.
    \40\ The proposed October 2018 SIP revision was intended to 
replace the portion of our FIP addressing Domtar and would also 
resolve the claims regarding Domtar in petitions for review of the 
FIP that are currently being held in abeyance, State of Arkansas v. 
EPA, No. 16-4270 (8th Cir.).
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    The October 2018 proposal included an administrative order as the 
enforceable mechanism for the emission limits established under the 
BART alternative; and the order also contained monitoring, reporting, 
and recordkeeping requirements for the boilers. During the State's 
public comment period, Domtar submitted comments stating that while it 
agrees with the BART alternative approach and with the emission limits 
themselves, it does not agree with the use of the administrative order 
as the enforceable mechanism of the proposed SIP revision. Domtar 
requested that the portion of its New Source Review (NSR) permit 
containing the regional haze requirements be included in the proposed 
SIP revision as the enforceable mechanism instead of the administrative 
order. ADEQ addressed Domtar's request in April 2019 by proposing a 
supplemental SIP revision to the October 2018 proposal. The 
supplemental SIP revision proposal replaced the administrative order 
with the incorporation of certain provisions of Domtar's revised NSR 
permit into the SIP as the enforceable mechanism for Domtar's regional 
haze requirements. On August 1, 2019, the ADEQ issued a final minor 
permit modification letter to Domtar,\41\ which included enforceable 
emission limitations and compliance schedules for the BART alternative.
---------------------------------------------------------------------------

    \41\ See ADEQ Air permit #0287-AOP-R22 (effective August 1, 
2019) included as part of the Phase III submittal and is included in 
the docket of this action.
---------------------------------------------------------------------------

    ADEQ submitted its third corrective regional haze SIP submittal to 
the EPA on August 13, 2019, which is the subject of this proposed 
rulemaking (the Arkansas Regional Haze Phase III SIP revision). The 
Phase III SIP revision includes Domtar's BART alternative approach and 
revises all of the prior BART determinations for Power Boilers No. 1 
and 2 at the Ashdown Mill. The Phase III SIP submittal also 
incorporates plantwide provisions from the August 1, 2019, permit 
including emission limits and conditions for implementing the BART 
alternative.\42\ If the EPA takes final action to approve the Arkansas 
Regional Haze Phase III SIP revision, ADEQ will have a fully-approved 
regional haze SIP for the first implementation period. The Arkansas 
Regional Haze NOX SIP revision,\43\ the Arkansas Regional 
Haze SO2 and PM SIP revision,\44\ and the Arkansas Regional 
Haze Phase III SIP revision (if approved by EPA) will together fully 
address all deficiencies of the 2008 Arkansas Regional Haze SIP that 
EPA previously identified in the March 12, 2012 partial approval/
disapproval action.\45\
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    \42\ See ADEQ Air permit #0287-AOP-R22, Section VI, Plantwide 
Conditions #32 to #43. The ``Regional Haze Program (BART 
Alternative) Specific Conditions'' portion of the Plantwide 
Conditions section of the permit states the following: ``For 
compliance with the CAA Regional Haze Program's requirements for the 
first planning period, the No. 1 and 2 Power Boilers are subject-to-
BART alternative measures consistent with 40 CFR 51.308. The terms 
and conditions of the BART alternative measures are to be submitted 
to EPA for approval as part of the Arkansas SIP. Upon initial EPA 
approval of the permit into the SIP, the permittee shall continue to 
be subject to the conditions as approved into the SIP even if the 
conditions are revised as part of a permit amendment until such time 
as the EPA approves any revised conditions into the SIP. The 
permittee shall remain subject to both the initial SIP-approved 
conditions and the revised conditions, until EPA approves the 
revised conditions.''
    \43\ See final action approved on February 12, 2018 (83 FR 
5927).
    \44\ See final action approved on September 27, 2019 (84 FR 
51033) and the proposed approval on November 30, 2018 (83 FR 62204).
    \45\ The proposed approval of the Arkansas Regional Haze Phase 
III SIP submittal is not proposing to revise the Arkansas Regional 
Haze Phase I or II SIP revisions.
---------------------------------------------------------------------------

H. Arkansas Visibility Transport

    Sections 110(a)(1) and (2) of the CAA direct each state to develop 
and submit to the EPA a SIP that provides for the implementation, 
maintenance, and enforcement of a new or revised NAAQS.\46\ This type 
of SIP submission is referred to as an infrastructure SIP. Section 
110(a)(1) provides the timing and procedural requirements for 
infrastructure SIPs. Specifically, each state is required to make a new 
SIP submission within three years after promulgation of a new or 
revised primary or secondary NAAQS. Section 110(a)(2) lists the 
substantive elements that states must address for infrastructure SIPs 
to be approved by the EPA. Section 110(a)(2)(D)(i) includes four 
distinct elements related to interstate transport of air pollution, 
commonly referred to as prongs, that must be addressed in 
infrastructure SIP submissions. The first two prongs are codified in 
section 110(a)(2)(D)(i)(I) and the third and fourth prongs are codified 
in section 110(a)(2)(D)(i)(II). These four prongs prohibit any source 
or type of emission activities in one state from:
---------------------------------------------------------------------------

    \46\ See the final rules promulgating the NAAQS requirements: 71 
FR 61144 (October 17, 2006); 77 FR 50033 (August 20, 2012); 80 FR 
11573 (March 4, 2015); 80 FR 38419 (July 6, 2015); 78 FR 53269 
(August 29, 2013); 73 FR 16436 (March 27, 2008). 81 FR 74504 
(October 26, 2016); 75 FR 35520 (June 22, 2010); 75 FR 6474 
(February 9, 2010); and 78 FR 3086 (January 15, 2013).
---------------------------------------------------------------------------

     Contributing significantly to nonattainment of the NAAQS 
in another state (prong 1);
     interfering with maintenance of the NAAQS in another state 
(prong 2);
     interfering with measures that prevent significant 
deterioration of air quality in another state (prong 3); and
     interfering with measures that protect visibility in 
another state (prong 4 or ``visibility transport'').
    We are only addressing the prong 4 element in this proposed action. 
The Prong 4 element is consistent with the requirements in the regional 
haze program, which explicitly require each state to address its share 
of emission reductions needed to meet the RPGs for surrounding Class I 
areas. The EPA most recently issued guidance that addressed prong 4 on 
September 13, 2013.\47\ The 2013 guidance indicates that a state can 
satisfy prong 4 requirements with a fully-approved regional haze SIP 
that meets 40 CFR 51.308 or 309. Alternatively, in the absence of a 
fully-approved regional haze SIP, a state may meet the prong 4 
requirements through a demonstration showing that emissions within its 
jurisdiction do not interfere with another air agency's plans to 
protect visibility. Lastly, the guidance states that prong 4 is 
pollutant-specific, so infrastructure SIPs only need to

[[Page 14853]]

address the particular pollutant (including precursors) for which there 
is a new or revised NAAQS for which the SIP is being submitted that is 
interfering with visibility protection.
---------------------------------------------------------------------------

    \47\ See ``Guidance on Infrastructure State Implementation Plan 
(SIP) Elements under CAA sections 110(a)(1) and 110(a)(2)'' by 
Stephen D. Page (Sept. 13, 2013), (pages 32-35).
---------------------------------------------------------------------------

    On March 24, 2017, the State submitted a SIP revision that 
addressed all four infrastructure prongs from section 110(a)(2)(D)(i) 
for the 2008 lead (Pb) NAAQS, the 2006 and 2012 PM2.5 NAAQS, 
the 2008 O3 NAAQS, the 2010 SO2 NAAQS, and the 
2010 NO2 NAAQS. We deferred taking action on the 
110(a)(2)(D)(i)(II) prong 4 portion of that infrastructure SIP for a 
future rulemaking with the exception of the 2008 Pb NAAQS.\48\ On 
August 10, 2018, the State also included a discussion on visibility 
transport in its Phase II Arkansas Regional Haze SO2 and PM 
SIP revision, but we deferred proposing action on the visibility 
transport requirements in that submittal too.\49\ In the Phase II SIP 
revision, ADEQ concluded that Missouri is on track to achieve its 
visibility goals; that observed visibility progress from Arkansas 
sources are not interfering with Missouri's RPG achievements for 
Hercules-Glades Wilderness and Mingo National Wildlife Refuge; and that 
no additional controls on Arkansas sources are necessary to ensure that 
other states' Class I areas meet their visibility goals for the first 
planning period. On October 4, 2019, the State submitted the Arkansas 
2015 O3 NAAQS Interstate Transport SIP revision to meet the 
requirements of CAA section 110(a)(2)(D) regarding interstate transport 
for the 2015 O3 NAAQS. In that SIP submittal, Arkansas also 
addressed the 2006 and 2012 PM2.5 NAAQS, the 2008 
O3 NAAQS, the 2010 SO2 NAAQS, and the 2010 
NO2 NAAQS prong 4 visibility transport obligations in 
110(a)(2)(D)(i)(II), and we are proposing to approve those prong 4 
requirements in this action. The State's prong 4 visibility transport 
analysis in the October 4, 2019 submittal supersedes the prong 4 
visibility transport portion of the March 24, 2017, infrastructure SIP 
submittal and supplements the August 10, 2018, Phase II Arkansas 
Regional Haze SO2 and PM SIP revision \50\ for the 2006 and 
2012 PM2.5 NAAQS, the 2008 and 2015 O3 NAAQS, the 
2010 SO2 NAAQS, and the 2010 NO2 NAAQS. All other 
applicable infrastructure SIP requirements in the October 4, 2019, SIP 
submission have been or will be addressed in separate rulemakings.
---------------------------------------------------------------------------

    \48\ The EPA approved the visibility transport requirement for 
the 2008 Pb NAAQS only in the February 2018 final action effective 
March 16, 2018 (see 83 FR 6470).
    \49\ See 84 FR 51033, 51054 (September 27, 2019).
    \50\ See 83 FR 62204 (November 30, 2018) for proposed approval 
and 84 FR 51033 (September 27, 2019) for final action. The Arkansas 
Regional Haze SO2 and PM SIP revision addressed separate 
CAA requirements related to interstate visibility transport under 
CAA section 110(a)(2)(D)(i)(II), but we did not take action on that 
part of the submittal. We are incorporating by reference the prong 4 
portion of the Arkansas Regional Haze SO2 and PM SIP 
revision in this proposed action.
---------------------------------------------------------------------------

II. Evaluation of the Arkansas Regional Haze Phase III SIP Submittal

    On August 13, 2019, the EPA received a SIP revision (The Arkansas 
Regional Haze Phase III SIP), which we are proposing to approve in this 
action. The submittal contains a BART alternative measure pursuant to 
40 CFR 51.308(e)(2) for Domtar Ashdown Mill's Power Boilers No. 1 and 
2.\51\ ADEQ submitted this SIP revision to address the remaining 
deficiencies identified by the EPA in the March 12, 2012 previous 
partial approval/disapproval action on the 2008 Arkansas Regional Haze 
SIP revision. The SIP revision establishes an alternative to BART for 
SO2, NOX, and PM10 for Power Boilers 
No. 1 and No. 2; and replaces all of the prior SIP-approved and FIP 
BART determinations for those units. Specifically, it replaces the SIP-
approved PM10 BART determination \52\ for Power Boiler No. 
1; the SO2 and NOX FIP BART determinations for 
Power Boiler No. 1; and the SO2, NOX, and 
PM10 FIP BART determinations for Power Boiler No. 2. The 
Phase III SIP revision includes the State's assessment of Domtar's BART 
alternative, including analysis of the modeled visibility impacts 
across four-affected Class I areas in Arkansas and Missouri: Caney 
Creek Wilderness, Upper Buffalo Wilderness, Hercules-Glades Wilderness, 
and Mingo National Wildlife Refuge.\53\ The BART alternative analysis 
is based on a demonstration that the clear weight of evidence of the 
alternative will result in greater reasonable progress than the FIP 
BART limits. We agree with the State's assessment and propose to 
approve the Arkansas Regional Haze Phase III SIP revision on the basis 
that it satisfies the requirements of 40 CFR 51.308(e)(2) as explained 
in further detail in each subsequent section. We also propose to 
withdraw the FIP provisions concerning BART for the Domtar power 
boilers, as they will be replaced by our approval of the State's BART 
alternative. In addition, we propose to approve additional requirements 
that rely on the Domtar BART alternative measure. These include the 
State's revisions to its long-term strategy and the components of the 
State's reasonable progress determination for Arkansas' Class I areas 
(discussed in sections III and IV). We also propose to approve the 
interstate visibility transport requirements under CAA section 
110(a)(2)(D)(i)(II) for pollutants that affect visibility in Class I 
areas in nearby states. Our evaluation of the interstate visibility 
transport requirements pertaining to a portion of the August 10, 2018, 
Phase II Arkansas Regional Haze SO2 and PM SIP, as 
supplemented by the Arkansas 2015 O3 NAAQS Interstate 
Transport SIP revision (submitted on October 4, 2019) is discussed in 
section V.
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    \51\ Previously, on March 20, 2018, Domtar provided to ADEQ a 
proposed BART alternative based on boiler operational changes, fuel 
switching and repurposing of Ashdown Mill to produce fluff paper. On 
September 5, 2018, Domtar proposed to ADEQ a revised BART 
alternative with new emission limits and modeling that would 
accommodate potential further changes in operation at the Ashdown 
Mill and it is included with this SIP submittal. See the associated 
September 4, 2018 TSD, ``Ashdown Mill BART Alternative TSD'' in the 
docket of this action in Docket No. EPA-R06-OAR-2015-0189.
    \52\ See the final action on March 12, 2012 (77 FR 14604).
    \53\ Arkansas has two Class I areas within its borders: Upper 
Buffalo and Caney Creek Wilderness areas. Upper Buffalo Wilderness 
area, located in Newton County, Arkansas, is an oak-hickory forest 
with intermittent portions of shortleaf pine located in the Ozark 
National Forest and offers 12,108 acres of boulder strewn and rugged 
scenery along the Buffalo River. Caney Creek Wilderness is located 
in Polk County, Arkansas, and covers 14,460 acres on the southern 
edge of the Ouachita National Forest and protects a rugged portion 
of the Ouachita Mountains. Two Class I areas outside Arkansas' 
borders at Hercules-Glades Wilderness and Mingo National Wildlife 
Refuge in Missouri are impacted by emissions from within Arkansas.
---------------------------------------------------------------------------

A. Summary of Arkansas' BART Alternative for Domtar Ashdown Mill

    The State's BART alternative operating conditions and emission 
rates

[[Page 14854]]

are summarized in Table 1.\54\ Under the BART alternative, Power Boiler 
No. 1 operates at maximum permitted emission rates consistent with the 
combustion of natural gas.\55\ The emission rates for Power Boiler No. 
2 were adjusted downward from their previous permitted emission rates 
of 984 pph SO2 and 574 pph NOX (44 and 51 
percent, respectively, of previous permitted rates).\56\ The 
PM10 emission rate for Power Boiler No. 2 is equivalent to 
the 2001 to 2003 baseline rate in the 2008 Arkansas Regional Haze SIP 
and the 2016 FIP, which is slightly less than the previous permitted 
maximum rate of 82 pph PM10 (99.5 percent of the prior 
authorized rate).
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    \54\ See Table 3 of the Arkansas Regional Haze Phase III 
submittal (pages 9-10). See also Plantwide Conditions #32 to #43 
from ADEQ Air permit #0287-AOP-R22.
    \55\ See ADEQ Air Permit No. #0287-AOP-R22. The BART alternative 
emission rates for Power Boiler No. 1 in the permit are 0.5 pph 
SO2, 191.1 pph NOX, and 5.2 pph 
PM10 and are based on the max design heat input capacity 
of 580 MMBtu/hr.
    \56\ The BART alternative emission rates for Power Boiler No. 2 
in the current ADEQ Air permit No. 0287-AOP-R22 are 44.2, 51, and 
99.5 percent of the previous permit rates. The previous permitted 
emission rates for Power Boiler No. 2 in ADEQ Air Permit No. 0287-
AOP-R20 were 984 pph SO2, 574 pph NOX, and 
82.0 pph PM10. These are based on emission limits of 1.2, 
0.7, and 0.1 lb/MMBtu for SO2, NOX, and 
PM10 with a design heat input capacity of 820 MMBtu/hr.

                                   Table 1--BART Alternative Emission Rates *
----------------------------------------------------------------------------------------------------------------
                                                                                                     Emission
                  Unit                        Operating scenario               Pollutant           rates  (pph)
----------------------------------------------------------------------------------------------------------------
Power Boiler No. 1......................  Burn only natural gas.....  SO2.......................             0.5
                                                                      NOX.......................           191.1
                                                                       PM10.....................             5.2
Power Boiler No. 2......................  Adjusted emission rates     SO2.......................             435
                                           for SO2 and NOX.
                                                                       NOX......................             293
                                                                      PM10......................            81.6
----------------------------------------------------------------------------------------------------------------
* These limits are for a thirty boiler-operating-day rolling average as defined in Plantwide Condition #32 of
  ADEQ Air Permit No. 0287-AOP-R22.

B. Demonstration That BART Alternative Achieves Greater Reasonable 
Progress

    Pursuant to 40 CFR 51.308(e)(2)(i), the State must demonstrate that 
the alternative measure will achieve greater reasonable progress than 
would have resulted from the installation and operation of BART at all 
sources subject-to-BART in the State and covered by the alternative 
program. This demonstration must be based on the following five 
criteria, which are addressed in the subsequent sections:
    (1) A list of all BART-eligible sources within the State.
    (2) A list of all BART-eligible sources and source categories 
covered by the alternative.
    (3) An analysis of BART and associated emission reductions.
    (4) The projected emission reductions achievable through the 
alternative measure.
    (5) A determination that the alternative achieves greater 
reasonable progress than BART.
1. List All BART-Eligible Sources Within the State
    Pursuant to 40 CFR 51.308(e)(2)(i)(A), the SIP must include a list 
of all BART-eligible sources within the State. The State included a 
list of facilities with BART-eligible sources in Arkansas in its 
original 2008 Arkansas Regional Haze SIP submittal.\57\ As part of the 
final 2012 action on the 2008 SIP submittal, the EPA approved the 
majority of the State's list of BART-eligible sources. The 2008 
Arkansas Regional Haze SIP omitted Georgia Pacific Crossett Mill Boiler 
6A from the list of BART-eligible sources,\58\ but it was later 
included in the list of BART-eligible sources adopted into APCEC 
Regulation No. 19, Chapter 15. The most recently updated BART-eligible 
source list by the State is in the August 8, 2018, Arkansas Regional 
Haze SO2 and PM SIP revision, which the EPA approved on 
September 27, 2019.\59\ This recent list includes the Domtar Ashdown 
Mill Power Boilers No. 1 and No. 2 as BART-eligible. Therefore, with 
this revision, all BART-eligible sources within the State have been 
identified in the Arkansas Regional Haze SIP. We propose to find that 
the existing list in the Arkansas Regional Haze SO2 and PM 
SIP revision fulfills the requirement of 40 CFR 51.308(e)(2)(i)(A) to 
provide a list of all BART-eligible sources within the State.
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    \57\ See Figure 9.1 and Table 9.1 (page 45) of the 2008 Arkansas 
Regional Haze SIP included in the docket of this proposed action. A 
detailed description of each BART-eligible unit is included in 
Appendix 9.1A.
    \58\ See 77 FR 14604, 14605 (March 12, 2012).
    \59\ See Table 1 (pages 8-10) of the Arkansas Regional Haze 
SO2 and PM SIP revision.
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2. List All BART-Eligible Sources and Source Categories Covered by the 
Alternative Program
    Pursuant to 40 CFR 51.308(e)(2)(i)(B), each BART-eligible source in 
the State must be subject to the requirements of the alternative 
program, have a federally enforceable emission limitation determined by 
the State and approved by the EPA as meeting BART in accordance with 
RAVI under 40 CFR 51.302(c) or source-specific BART under 40 CFR 
51.308(e)(1); or otherwise addressed under source-specific BART or the 
40 CFR 51.308(e)(4) BART alternative provisions. In this instance, the 
BART alternative measure covers two BART-eligible units, Power Boilers 
No. 1 and 2 at Domtar Ashdown Mill. All other BART-eligible sources 
have already been addressed in the 2008 Arkansas Regional Haze SIP and 
subsequent SIP revisions.\60\ As a result, we propose to find that the 
Arkansas Regional Haze Phase III SIP revision meets the requirement of 
40 CFR 51.308(e)(2)(i)(B).
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    \60\ See the 2017 Arkansas Regional Haze NOX SIP 
revision approved on February 12, 2018 (83 FR 5927), and the 2018 
Arkansas Regional Haze SO2 and PM SIP revision approved 
on September 27, 2019 (84 FR 51033).
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3. Analysis of BART and Associated Emission Reductions
    Pursuant to 40 CFR 51.308(e)(2)(i)(C), the SIP must include an 
analysis of BART and the associated emission reductions achievable at 
the Domtar Ashdown Mill for Power Boilers No. 1 and 2. ADEQ relied on 
the BART determinations in the 2016 FIP for comparison to the baseline 
emissions and analysis of emission reductions under BART. The BART 
determinations in the 2016 FIP were based on consideration of ADEQ's 
2006 and 2007

[[Page 14855]]

BART analyses,\61\ a supplemental BART analysis (dated May 2014) 
developed by Domtar that included a five-factor analysis,\62\ and 
additional information regarding the existing venturi scrubbers for 
Power Boiler No. 2.\63\ The SO2 BART determination for Power 
Boiler No. 1 is the SO2 baseline emission rate of 21.0 pph 
or 504 pounds per day (ppd) on a thirty boiler-operating-day rolling 
average, which does not require the installation of additional control 
equipment. The SO2 BART determination for Power Boiler No. 2 
is an emission limit of 0.11 lb/MMBtu on a thirty boiler-operating-day 
rolling average, based on the boiler's maximum heat input of 820 MMBtu/
hr. This is achieved by operating the existing venturi scrubbers at 
ninety percent control efficiency with additional scrubbing reagent and 
upgraded scrubber pumps. This results in a controlled emission rate of 
91.5 pph SO2 for Power Boiler No. 2. The NOX BART 
determination for Power Boiler No. 1 is an emission limit of 207.4 pph 
on a thirty boiler-operating-day rolling average with no additional 
control equipment needed. This emission limit is based on the boiler's 
NOX baseline emission rate. The NOX BART 
determination for Power Boiler No. 2 is an emission limit of 345 pph on 
a thirty boiler-operating-day rolling average, achieved by the 
installation and operation of low NOX burners. The 
PM10 BART determination for Power Boiler No. 2 is subject to 
the maximum achievable control technology (MACT) standard for boilers 
promulgated under CAA section 112, which provides for a PM10 
emission limit of 0.44 lb/MMBtu and no additional control equipment. 
Power Boiler No. 2 falls under the ``biomass hybrid suspension grate'' 
subcategory for the Boiler MACT at 40 CFR part 63, subpart DDDDD-
National Emission Standards for Hazardous Air Pollutants (NESHAP) for 
Major Sources: Industrial, Commercial, and Institutional Boilers and 
Process Heaters. Finally, the EPA approved the State's PM10 
BART determination of 0.07 lb/MMBtu for Power Boiler No. 1 in 2012, 
which was based on the then-final Boiler MACT. The FIP BART limits and 
the SIP-approved PM10 BART limit for Power Boiler No. 1 are 
listed in Table 2.
---------------------------------------------------------------------------

    \61\ See ``Best Available Retrofit Technology Determination 
Domtar Industries Inc., Ashdown Mill (AFIN 41-00002),'' originally 
dated October 31, 2006 and revised on March 26, 2007, prepared by 
Trinity Consultants Inc. This was included as part of the Phase III 
SIP submittal and included in the docket of this action in Docket 
No. EPA-R06-OAR-2015-0189.
    \62\ See ``Supplemental BART Determination Information Domtar 
A.W. LLC, Ashdown Mill (AFIN 41-00002),'' originally dated June 28, 
2013 and revised on May 16, 2014, prepared by Trinity Consultants 
Inc. in conjunction with Domtar A.W. LLC. This was included as part 
of the Phase III SIP submittal and included in the docket of this 
action in Docket No. EPA-R06-OAR-2015-0189.
    \63\ See final FIP action on September 27, 2016 (81 FR 66332) as 
corrected on October 4, 2016 (81 FR 68319) and the associated 
technical support document (TSD), ``AR020.0002-00 TSD for EPA's 
Proposed Action on the Arkansas Regional Haze FIP'' in Docket No. 
EPA-R06-OAR-2015-0189 for the FIP BART analysis for SO2 
and NOX for Power Boiler No. 1; and SO2, 
NOX, and PM10 for Power Boiler No. 2. The FIP 
TSD was included as part of the Phase III SIP submittal and included 
in the docket of this action.

                Table 2--Summary of EPA-Approved SIP and FIP BART Limits for Domtar Ashdown Mill
----------------------------------------------------------------------------------------------------------------
                                                                  Emission limits *
                Unit                ----------------------------------------------------------------------------
                                               SO2                     NOX                       PM10
----------------------------------------------------------------------------------------------------------------
Power Boiler No. 1.................  504 ppd...............  207.4 pph.............  0.07 lb/MMBtu.**
Power Boiler No. 2.................  91.5 pph..............  345 pph...............  Satisfied by reliance on
                                                                                      applicable PM10 standard
                                                                                      under 40 CFR part 63,
                                                                                      subpart DDDDD (currently
                                                                                      0.44 lb/MMBtu).
----------------------------------------------------------------------------------------------------------------
* See the final BART emission limits in Table 1 of the final action of the approved FIP (81 FR 66332, 66339).
** The EPA approved the State's PM10 BART determination for Power Boiler No. 1 in the March 12, 2012, final
  action (77 FR 14604).

    The baseline emission rates assumed in the 2016 FIP for purposes of 
determining the visibility improvement anticipated from BART controls 
(based on Domtar's May 2014 supplemental BART analysis) are summarized 
in Table 3. The State did not make any changes in the Phase III SIP 
submittal to the modeled baseline emission rates presented in the 2014 
report. ADEQ is relying on these baseline emission rates for comparison 
of the BART alternative to BART (see Table 3 note). The baseline rates 
for Power Boiler No. 1 in Domtar's May 2014 BART analysis and our 2016 
FIP were based on the 2009 to 2011 adjusted baseline period. The 
adjusted 2009 to 2011 baseline rates for Power Boiler No. 1, as 
presented in the 2016 FIP, were 21 pph SO2; 207.4 pph 
NOX; and 30.4 pph PM10. These replaced the 2001 
to 2003 original baseline rates (442.5 pph SO2; 179.5 pph 
NOX; and 169.5 pph PM10) submitted by the State. 
The 2009 to 2011 period was used as the baseline for Power Boiler No. 1 
because a WESP was installed on Power Boiler No. 1 in 2007 to meet MACT 
standards under CAA section 112, resulting in a reduction in PM and 
SO2 emissions from Power Boiler No. 1. In the 2016 FIP, we 
found that the use of the 2009 to 2011 baseline rates to be consistent 
with the BART Guidelines, which provide that the baseline emission 
rates should represent a realistic depiction of anticipated annual 
emissions for the source. The baseline rates for Power Boiler No. 2 
were based on the original 2001 to 2003 baseline period. The 2001 to 
2003 baseline rates for Power Boiler No. 2 as presented in the 2016 FIP 
were 788.2 pph SO2; 526.8 pph NOX; and 81.6 pph 
PM10.

                               Table 3--Summary of Baseline Annual Emission Rates
----------------------------------------------------------------------------------------------------------------
                                                                              Emission rates (tpy) *
                              Unit                               -----------------------------------------------
                                                                        SO2             NOX            PM10
----------------------------------------------------------------------------------------------------------------
Power Boiler No. 1 (2009 to 2011 Baseline)......................              92           908.4           133.2
Power Boiler No. 2 (2001 to 2003 Baseline)......................           3,452         2,307.4           357.4
                                                                 -----------------------------------------------

[[Page 14856]]

 
    Total.......................................................           3,544         3,215.8           490.6
----------------------------------------------------------------------------------------------------------------
* These baseline rates from the FIP are being incorporated into this proposed action. These baseline emission
  rates are based on Table 43 of the April 8, 2015 proposed FIP (80 FR 18979) in terms of pph but have been
  converted here to tpy. Supporting documentation for this data was included in the SIP submittal from the State
  and is included in the docket of this action.

    A summary of the annual emissions resulting from the implementation 
of BART estimated by the State in the Phase III SIP is shown in Table 
4. These rates are based on the BART limits from the 2016 Arkansas 
Regional Haze FIP (see Table 2) and the approved PM10 BART 
limit for Power Boiler No. 1 from the 2008 Arkansas Regional Haze SIP 
in the 2012 action.

                                       Table 4--Annual BART Emission Rates
----------------------------------------------------------------------------------------------------------------
                                                                              Emission rates (tpy) *
                              Unit                               -----------------------------------------------
                                                                        SO2             NOX            PM10
----------------------------------------------------------------------------------------------------------------
Power Boiler No. 1..............................................              92           908.4        ** 177.8
Power Boiler No. 2..............................................           400.7         1,511.1        [dagger]
                                                                                                          359.16
                                                                 -----------------------------------------------
    Total.......................................................           492.7         2,419.5           536.9
----------------------------------------------------------------------------------------------------------------
* These BART rates are being incorporated into this proposed action. These BART emission rates are based on
  Table 1, ``Final BART Emission Limits'' of the September 27, 2016, final action on the FIP (81 FR 66332,
  66339) and the EPA-approved PM10 BART determination for Power Boiler No. 1 in the March 12, 2012, final action
  (77 FR 14604). These emission rates were reported in terms of pph but have been converted here to tpy.
  Supporting documentation for this data was included in the SIP submittal from the State and is included in the
  docket of this action.
** The estimated annual PM10 emission rate for Power Boiler No. 1 was calculated in Domtar's May 2014
  supplemental BART determination report using 0.066 lb/MMBtu (an emission factor developed from analysis of
  past stack testing) and a heat input rate from 2009 to 2011 of 11,069.67 MMBtu/day (461 MMBtu/hr), resulting
  in 30.4 pph PM10 (or 133.2 tpy). In the Phase III SIP submittal, for purposes of comparing the emission
  reductions achievable through BART versus the BART alternative, the State calculated the PM10 BART emission
  rate for Power Boiler No. 1 by multiplying the actual PM10 BART determination (0.07 lb/MMBtu) that was
  approved in the 2012 final action and a maximum design heat input capacity of 580 MMBtu/hr to reflect the
  current emission reductions achievable (resulting in 40.6 pph PM10 or 177.8 tpy) instead of relying on the
  analysis from the 2014 BART determination.
[dagger] This does not reflect the FIP BART limit which is subject to the 40 CFR part 63, subpart DDDDD Boiler
  MACT PM10 emission limit of 0.44 lb/MMBtu for the biomass hybrid suspension grate subcategory (resulting in
  360.8 pph). Instead, the State used the more conservative permit limit of 0.1 lb/MMBtu and the design heat
  input capacity of 820 MMBtu/hr, resulting in 82 pph, which is more stringent than the FIP limit.

    Table 5 compares the BART controlled emissions from Power Boilers 
No. 1 and 2 to the baseline emissions and shows the estimated annual 
emission reductions achievable with BART. The BART controls result in 
reduced SO2 and NOX emissions for Power Boiler 
No. 2 only. There are no SO2 and NOX emission 
reductions expected to result from Power Boiler No. 1 since the 
SO2 and NOX BART emission rates for Power Boiler 
No. 1 are consistent with the baseline. BART controls for Power Boiler 
No. 2 reduce the total SO2 and NOX annual 
emissions by 3,051 and 796 tpy from the baseline (86 and 25 percent 
decreases, respectively). Calculated emissions under the BART controls 
for PM10 exhibit slight increases in PM10 
emissions for both power boilers totaling 46.3 tpy above the baseline 
(nine percent increase in PM10). As mentioned in the Table 4 
notes, this difference is because the calculated baseline emissions by 
the State were based on stack test data and actual heat input capacity 
while the estimated BART emissions were based on the BART emission 
limit and the maximum capacity. We propose to find that the Arkansas 
Regional Haze Phase III SIP revision has met the requirement for an 
analysis of BART and associated emission reductions achievable at the 
Domtar Ashdown Mill for Power Boilers No. 1 and 2 under 40 CFR 
51.308(e)(2)(i)(C).

                            Table 5--Domtar Emission Reductions Achievable With BART
----------------------------------------------------------------------------------------------------------------
                                                                    Power boilers 1 and 2 total emissions (tpy)
                            Condition                            -----------------------------------------------
                                                                        SO2             NOX            PM10
----------------------------------------------------------------------------------------------------------------
Baseline........................................................         3,544.3         3,215.8           490.6
BART............................................................           492.7         2,419.5           536.9
Emission Reduction..............................................           3,051           795.5           -46.3
----------------------------------------------------------------------------------------------------------------
* A negative number indicates an increase in emissions from the baseline.

[[Page 14857]]

4. Analysis of Projected Emission Reductions Achievable Through BART 
Alternative
    Pursuant to 40 CFR 51.308(e)(2)(i)(D), the SIP must also include an 
analysis of the projected emission reductions achievable through the 
BART alternative measure. The estimated annual emission reductions 
achievable with the BART alternative can be seen in Table 6. The BART 
alternative would result in a decrease in SO2, 
NOX, and PM10 emissions from the baseline for 
both power boilers. The BART alternative results in greater emission 
reductions of NOX and PM10 than the BART 
controls. The implemented BART alternative controls would reduce 
NOX and PM10 emissions by 1,096 and 111 tpy, 
respectively, from the baseline. The BART alternative reduces fewer 
SO2 emissions compared to the BART controls (BART achieves 
3,051 tpy SO2 reduction) but still achieves a decrease of 
1,637 tpy SO2 from the baseline. Since the distribution of 
emission reductions between the BART alternative and BART are slightly 
different, the State conducted dispersion modeling to determine 
differences in visibility improvement between BART and the alternative 
measure as discussed in section II.B.5. We propose to find that ADEQ 
has met the requirement in this section for reporting an analysis of 
the projected emission reductions achievable through the BART 
alternative measure under 40 CFR 51.308(e)(2)(i)(D).

                    Table 6--Domtar Emission Reductions Achievable With the BART Alternative
----------------------------------------------------------------------------------------------------------------
                                                                    Power boilers 1 and 2 total emissions (tpy)
                            Condition                            -----------------------------------------------
                                                                        SO2             NOX            PM10
----------------------------------------------------------------------------------------------------------------
Baseline........................................................         3,544.3         3,215.8           490.6
BART Alternative................................................         1,907.5         2,120.3          380.18
Emission Reduction..............................................           1,637           1,096             111
----------------------------------------------------------------------------------------------------------------

5. Determination That Alternative Achieves Greater Reasonable Progress 
Than BART
    Pursuant to 40 CFR 51.308(e)(2)(i)(E), the State must provide a 
determination under 40 CFR 51.308(e)(3) or otherwise based on the clear 
weight of evidence that the alternative measure achieves greater 
reasonable progress than BART. Based on the data provided by Domtar in 
the BART alternative analysis, ADEQ performed a clear weight of 
evidence approach to determine whether the Ashdown Mill satisfies the 
requirements of 40 CFR 51.308(e)(2)(i)(E). Factors which can be used in 
a weight of evidence determination in this context may include, but are 
not limited to, future projected emissions levels under the alternative 
as compared to under BART and future projected visibility conditions 
under the two scenarios. When comparing the summary of overall emission 
reductions in Tables 5 and 6, the BART alternative achieves greater 
emission reductions than the BART controls for NOX and 
PM10, but not for SO2. Because the BART controls 
achieve higher SO2 emission reductions than the BART 
alternative, the State also relied on a modeling analysis to support 
its conclusion that Domtar's BART alternative is better than BART.\64\ 
This weight of evidence analysis is based on the comparison of 
emissions under the BART and alternative control scenarios, as well as 
a modified version of the two-part modeling test set forth in 40 CFR 
51.308(e)(3), and described in section I.D of this action. The State 
used an air quality modeling methodology approach using the maximum 
98th percentile visibility impact of three modeled years using the 
CALPUFF model instead of modeled visibility conditions for the twenty 
percent best and worst days. This modeling approach differs from the 
modeling contemplated under 40 CFR 51.308(e)(3) for BART alternatives. 
However, this approach is consistent with the approach recommended by 
the BART guidelines \65\ for comparing different control options at a 
single source when developing BART determinations relying on the 98th 
percentile visibility impact as the key metric,\66\ and is also 
consistent with the methodology followed in EPA's 2016 FIP BART 
determination for Domtar. This approach is, therefore, acceptable for 
the comparison of the proposed BART alternative to the FIP BART for 
Domtar since it is the same modeling used to determine BART in the FIP, 
and the BART alternative is focused on only the BART sources at Domtar.
---------------------------------------------------------------------------

    \64\ See BART Alternative Analysis Domtar A.W. LLC, Ashdown Mill 
(AFIN 41-00002) submitted March 20, 2018.
    \65\ See 40 CFR 51 Appendix Y section III.A.3 and IV.D.5, 
``Guidelines for BART Determinations Under the Regional Haze Rule.'' 
CALPUFF is a single source air quality model that is recommended in 
the BART Guidelines. Since CALPUFF was used for this BART 
alternative analysis, the modeling results were post-processed in a 
manner consistent with the BART guidelines.
    \66\ The EPA recognized the uncertainty in the CALPUFF modeling 
results when the EPA made the decision, in the final BART 
Guidelines, to recommend that the model be used to estimate the 98th 
percentile visibility impairment rather than the highest daily 
impact value. ``Most important, the simplified chemistry in the 
model tends to magnify the actual visibility effects of that source. 
Because of these features and the uncertainties associated with the 
model, we believe it is appropriate to use the 98th percentile--a 
more robust approach that does not give undue weight to the extreme 
tail of the distribution.'' (see 70 FR 39104, 39121).
---------------------------------------------------------------------------

    ADEQ considered two methods of modeling evaluation provided by 
Domtar for this approach of using the maximum 98th percentile 
visibility impact. Method 1 assesses visibility impairment on a per 
source per pollutant basis and does not account for the full chemical 
interaction of emissions from the two boilers. Method 1 was performed 
to create a direct comparison with the approach that the EPA used in 
the Arkansas Regional Haze FIP, based on the modeling submitted by 
Domtar in the 2014 analysis. The 2014 Domtar analysis and the FIP 
focused on modeling each unit and pollutant separately to evaluate the 
potential visibility benefit from specific controls at each unit to 
inform the BART determination. In method 2, all sources and pollutants 
were combined into a single modeling run per year for the baseline and 
each control scenario. Method 2 allows for interaction of the 
pollutants from both boilers, as emitted pollutants from each unit 
disperse and compete for the same reactants in the atmosphere, 
providing modeled overall impacts due to emissions from both units. The 
State followed the same general CALPUFF modeling protocol and used the 
same meteorological data inputs for the BART alternative assessment as 
discussed in Appendix B to the FIP TSD.\67\ Only the modeled

[[Page 14858]]

emission rates change to represent the modeled scenarios for each 
method.
---------------------------------------------------------------------------

    \67\ See final FIP action on September 27, 2016 (81 FR 66332) as 
corrected on October 4, 2016 (81 FR 68319) and the associated FIP 
TSD, titled ``AR020.0002-00 TSD for EPA's Proposed Action on the AR 
RH FIP'' which was included in the SIP submittal from the State and 
in the docket of this action. See Docket No. EPA-R06-OAR-2015-0189 
for a detailed discussion of the FIP modeled emission rates and 
results of the visibility modeling.
---------------------------------------------------------------------------

    Domtar completed the BART alternative analysis using both methods 
and documented that the proposed BART alternative results in greater 
visibility improvement than the BART controls at Caney Creek and on 
average across the four Class I areas. The modeled baseline visibility 
impairment, in deciviews (dv), was compared to the modeled visibility 
impairment under the implementation of the modeled control scenarios 
for BART and the BART alternative. ADEQ included an analysis utilizing 
method 1 that shows that the BART alternative controls achieve greater 
overall reductions in visibility impairment ([Delta]dv) from the 
baseline cumulatively across the four Class I areas when compared to 
BART (0.549 [Delta]dv for the alternative versus 0.473 [Delta]dv for 
BART).\68\ ADEQ also included the visibility improvement anticipated 
(see Tables 7 and 8) at each Class I area utilizing method 2 (the full 
chemistry assessment method).\69\ ADEQ determined that the visibility 
benefits contained in Table 7 from method 2 and the BART determinations 
\70\ in Table 2 (see section II.B.3) form an appropriate BART benchmark 
for the purposes of the evaluation of Domtar's BART alternative. We 
agree with ADEQ that because method 2 provides for the full chemical 
interaction of emissions from both power boilers, method 2 analysis 
results shown in Tables 7 and 8 are a more reliable assessment of the 
anticipated overall visibility improvement of controls than method 1 
analysis results under each scenario.
---------------------------------------------------------------------------

    \68\ See Table 4 of the Arkansas Regional Haze Phase III SIP 
revision to see the method 1 results (page 11).
    \69\ See Table 5 (page 12) of the Arkansas Regional Haze Phase 
III submittal for a comparison of the cumulative visibility 
improvement under BART versus the BART alternative. See also the 
associated September 4, 2018, ``Ashdown Mill BART Alternative TSD'' 
which was included in the SIP submittal from the State and in the 
docket of this action in Docket No. EPA-R06-OAR-2015-0189.
    \70\ Associated with the approved PM10 BART 
determination for Power Boiler No. 1 in the 2008 SIP and the FIP 
BART determinations for SO2, NOX, and 
PM10 for Power Boilers No. 1 and 2.

   Table 7--Method 2--Visibility Improvement From BART Controls (98th Percentile Impacts) Max of Three Modeled
                                                      Years
----------------------------------------------------------------------------------------------------------------
                                                                                                    Visibility
                                                                                                    improvement
                 Unit                         Class I area         Baseline (dv)     BART (dv)     from controls
                                                                                                    ([Delta]dv)
----------------------------------------------------------------------------------------------------------------
Both Boilers..........................  Caney Creek Wilderness..           1.137           0.776           0.361
                                        Upper Buffalo Wilderness           0.163           0.103           0.060
                                        Hercules-Glades                    0.118           0.057           0.061
                                         Wilderness.
                                        Mingo National Wildlife            0.072           0.038           0.034
                                         Refuge.
                                       -------------------------------------------------------------------------
    Total.............................  ........................            1.49           0.974           0.516
----------------------------------------------------------------------------------------------------------------

 Table 8--Method 2--Visibility Improvement From BART Alternative Controls (98th Percentile Impacts) Max of Three
                                                  Modeled Years
----------------------------------------------------------------------------------------------------------------
                                                                                                    Visibility
                                                                                       BART         improvement
                 Unit                         Class I area         Baseline (dv)    alternative    from controls
                                                                                       (dv)         ([Delta]dv)
----------------------------------------------------------------------------------------------------------------
Both boilers..........................  Caney Creek Wilderness..           1.137           0.753           0.384
                                        Upper Buffalo Wilderness           0.163           0.104           0.059
                                        Hercules-Glades                    0.118           0.069           0.049
                                         Wilderness.
                                        Mingo National Wildlife            0.072           0.044           0.028
                                         Refuge.
                                       -------------------------------------------------------------------------
    Total.............................  ........................            1.49            0.97           0.520
----------------------------------------------------------------------------------------------------------------

    The BART alternative modeling in Table 8 demonstrates that 
visibility does not degrade in any Class I area from the baseline and 
shows greater visibility improvement at Caney Creek and cumulatively 
across the four impacted Class I areas than the modeled BART controls 
in Table 7. Despite a smaller reduction in SO2 emissions 
than BART (a 1,414 tpy SO2 difference), the BART alternative 
results in 300 tpy fewer NOX emissions and 157 tpy fewer 
PM10 emissions compared to BART. The additional reduction in 
NOX emissions under the BART alternative controls results in 
more overall modeled visibility improvement than BART even with the 
smaller reduction in SO2 emissions. Greater visibility 
improvement occurs because Domtar's baseline NOX emissions 
contribute more to visibility impairment across all four Class I areas 
for Power Boiler No. 1, and also contribute more at Caney Creek for 
Power Boiler No. 2 than other pollutants.\71\ Specifically, for Power 
Boiler No. 1, baseline modeled NO3- and 
NO2 impacts have the highest contribution to visibility 
impairment at all Class I areas. For Power Boiler No. 2, baseline 
modeled NO3- and NO2 impacts are the 
primary driver for visibility impacts at Caney Creek, which is the 
Class I area impacted the most by the Domtar units. As a result, for 
Power Boiler No. 2, the visibility impacts resulting from 
NOX at Caney Creek outweigh SO42- 
species contributions (from SO42- precursors) to 
impacts at the other three Class I areas combined (see Table 9). The 
baseline visibility impacts and the benefits modeled under the control 
scenarios at Caney Creek are significantly larger than at the other 
Class I areas.
---------------------------------------------------------------------------

    \71\ See Appendix C ``Supplemental BART Determination 
Information Domtar A.W. LLC, Ashdown Mill (AFIN 41-00002),'' 
originally dated June 28, 2013 and revised on May 16, 2014, prepared 
by Trinity Consultants Inc. in conjunction with Domtar A.W. LLC.

[[Page 14859]]

                      Table 9--Baseline CALPUFF Modeled Pollutant Species Contributions to Impacts From Power Boilers No 1 and 2 *
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                               98th                       Species contribution to impacts
                                                                            Percentile   ---------------------------------------------------------------
                   Unit                             Class I area            visibility        % SO42-
                                                                           impacts (dv)                       % NO3-          % PM10           % NO2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Power Boiler No. 1........................  Caney Creek Wilderness......           0.335            2.23           85.26            6.68            5.83
                                            Upper Buffalo Wilderness....           0.038            2.75           85.89            8.03            3.32
                                            Hercules-Glades Wilderness..           0.020            2.70           91.82            3.94            1.55
                                            Mingo National Wildlife                0.014            4.03           90.06            5.13            0.78
                                             Refuge.
Power Boiler No. 2........................  Caney Creek Wilderness......           0.844           22.04           70.68            4.58            2.69
                                            Upper Buffalo Wilderness....           0.146           76.99           20.76            2.26               0
                                            Hercules-Glades Wilderness..           0.105           61.17           37.68            1.06            0.09
                                            Mingo National Wildlife                0.065           81.46           15.47            3.07               0
                                             Refuge.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Max values among the three modeled years.

    ADEQ determined that the BART alternative controls reduce the 
overall visibility impairment from the baseline by 0.520 [Delta]dv for 
method 2 and is greater than the overall visibility improvement modeled 
under BART, which is 0.516 [Delta]dv. ADEQ noted that the most impacted 
Class I area, Caney Creek (1.137 dv baseline impairment), improves the 
greatest (0.384 [Delta]dv) with the BART alternative for method 2, and 
would experience greater visibility improvement under the BART 
alternative scenario than under the BART scenario, which improves by 
0.361 [Delta]dv. Given that baseline impacts at Caney Creek are much 
larger than impacts at the other Class I areas, it is reasonable to 
give greater weight to visibility benefits at Caney Creek due to the 
alternative over BART. The baseline visibility impacts and the level of 
visibility benefit from controls at the other three Class I areas are 
smaller than those at Caney Creek and well below the 0.5 dv threshold 
used by the State to determine if a source contributes to visibility 
impairment at a Class I area. We took this same approach in our 2016 
FIP to emphasize the visibility benefits at Caney Creek when 
considering different potential BART controls. Our FIP analysis also 
showed that the anticipated visibility benefits due to potential BART 
controls at the other three Class I areas were much smaller.\72\
---------------------------------------------------------------------------

    \72\ See 80 FR 18944, 18978-18989 (April 8, 2015) and 81 FR 
66332, 66347 (September 27, 2016).
---------------------------------------------------------------------------

    Tables 10 and 11, provided by the EPA to complement the State's 
analysis, compare the average visibility impact across the top ten 
highest impacted days at each Class I area (average 8th to 17th 
highest).\73\ This analysis provides a broader look at those days with 
the highest impacts at each Class I area. The results are consistent 
with the State's analysis based on the 98th percentile day, which was 
selected as representative of the highest impact (the 8th highest 
day).\74\ The average results across the top ten highest impacted days 
also support that it is appropriate to focus on Caney Creek impacts 
(0.9819 dv baseline impairment) since they are much larger than impacts 
at the other Class I areas (see Table 10). The BART alternative results 
in more visibility improvement at Caney Creek and slightly less at the 
other Class I areas when compared to the BART limits, but the 
visibility improvement at Caney Creek outweighs the difference in 
visibility benefit at the other three Class I areas altogether. On 
average, (see Table 11) the BART alternative controls achieve greater 
overall visibility improvement from the baseline compared to BART for 
the ten highest impacted days (0.439 [Delta]dv for the alternative 
versus 0.423 [Delta]dv for BART).
---------------------------------------------------------------------------

    \73\ This data is based on the CALPUFF modeling provided by 
Domtar and relied on by the State in the Phase III SIP. See ``EPA--
CALPUFF summary for Method 2.xlsx'' for the EPA's summary of the 
modeling data, available in the docket for this action.
    \74\ See 70 FR 39104, 39121 (July 6, 2005), Regional Haze 
Regulations and Guidelines for Best Available Retrofit Technology 
(BART) Determinations.

                  Table 10--Average Modeled Visibility Impacts of the Ten Highest Impacted Days
                                           [Average 8th-17th highest]
----------------------------------------------------------------------------------------------------------------
                                                                   Visibility impacts (dv) (max of three modeled
                                                                                      years)
                              Area                               -----------------------------------------------
                                                                     Baseline       FIP limits      Alternative
----------------------------------------------------------------------------------------------------------------
Caney Creek Wilderness..........................................           0.982           0.692           0.655
Hercules-Glades Wilderness......................................           0.086           0.045           0.053
Mingo National Wildlife Refuge..................................           0.066           0.031           0.039
Upper Buffalo Wilderness........................................           0.138           0.082           0.087
                                                                 -----------------
    Total.......................................................           1.273           0.850           0.834
----------------------------------------------------------------------------------------------------------------

[[Page 14860]]

  Table 11--Average Visibility Improvement of the Ten Highest Impacted
                                  Days
                       [Average 8th-17th highest]
------------------------------------------------------------------------
                                              Visibility improvement
                                             ([Delta]dv) (max of three
                                                  modeled years)
                  Area                   -------------------------------
                                                               BART
                                               BART         alternative
------------------------------------------------------------------------
Caney Creek Wilderness..................           0.290           0.327
Hercules-Glades Wilderness..............           0.041           0.034
Mingo National Wildlife Refuge..........           0.035           0.027
Upper Buffalo Wilderness................           0.057           0.051
                                         -------------------------------
    Total...............................           0.423           0.439
------------------------------------------------------------------------

    Table 12, also provided by the EPA to complement the State's 
analysis, evaluates the modeled number of days impacted by Domtar over 
1.0 dv and 0.5 dv for each scenario at each Class I area.\75\ These 
metrics provide additional information comparing the frequency and 
duration of higher visibility impacts. Caney Creek is the only Class I 
area with days of modeled visibility impacts from Domtar greater than 
0.5 dv. Overall, the FIP limits and the BART alternative both 
significantly reduce the number of impacted days over 1.0 dv and 0.5 dv 
from the baseline at Caney Creek. Table 12 shows that both the FIP 
limits and the BART alternative reduce the total modeled days with 
visibility impacts over 1.0 dv from fifteen days in the baseline to 
four days for each scenario. For days with modeled visibility impacts 
over 0.5 dv, the FIP limits reduce the number of days from 82 to 36, 
compared to the BART alternative which reduces the number to 37 days. 
This metric of days impacted over 0.5 dv very slightly favors the FIP 
limits over the BART alternative.
---------------------------------------------------------------------------

    \75\ This data is based on the CALPUFF modeling provided by 
Domtar and relied on by the State in the Phase III SIP revision. See 
``EPA--CALPUFF summary for Method 2.xlsx'' for the EPA's summary of 
the modeling data, available in the docket for this action.

                 Table 12--Modeled Number of Days With Visibility Impacts Over 0.5 dv and 1.0 dv
----------------------------------------------------------------------------------------------------------------
                                                  Baseline  (days)     FIP limits  (days)    Alternative  (days)
                                               -----------------------------------------------------------------
                                  Area          [Delta]dv  [Delta]dv  [Delta]dv  [Delta]dv  [Delta]dv  [Delta]dv
                                                   >=0.5      >=1.0      >=0.5      >=1.0      >=0.5      >=1.0
----------------------------------------------------------------------------------------------------------------
2001...................  Caney Creek..........         41         10         23          4         23          3
                         Upper Buffalo,                 0          0          0          0          0          0
                          Hercules-Glades, and
                          Mingo.
2002...................  Caney Creek..........         22          4          7          0          8          1
                         Upper Buffalo,                 0          0          0          0          0          0
                          Hercules-Glades, and
                          Mingo.
2003...................  Caney Creek..........         19          1          6          0          6          0
                         Upper Buffalo,                 0          0          0          0          0          0
                          Hercules-Glades, and
                          Mingo.
                                               ------------
    Total..............  Caney Creek..........         82         15         36          4         37          4
                         Upper Buffalo,                 0          0          0          0          0          0
                          Hercules-Glades, and
                          Mingo.
----------------------------------------------------------------------------------------------------------------

    In accordance with our regulations governing BART alternatives, we 
support the use of a weight of evidence determination as an alternative 
to the methodology set forth in 40 CFR 51.308(e)(3).\76\ In evaluating 
Arkansas' weight of evidence demonstration, we have evaluated ADEQ's 
analysis and additional model results (relying primarily on the 
analysis of the 98th percentile impacts at Caney Creek), the analysis 
of emission reductions, and the analysis of Domtar's visibility impacts 
due to NO3- compared to SO4\2\ 
-, which all support the conclusion that the BART 
alternative provides for greater reasonable progress than BART. In 
addition, we also considered our analysis of the ten highest impacted 
days and our analysis of the number of days impacted over 0.5 dv and 
1.0 dv. Our analysis of the ten highest impacted days similarly 
supports the conclusion that the BART alternative provides for greater 
reasonable progress than BART, but the analysis of the number of days 
impacted over 0.5 dv and 1.0 dv slightly favored BART over the BART 
alternative. This single metric, however, on which BART performed 
better than the BART alternative (days impacted over 0.5 dv) is not 
sufficient to outweigh the substantial evidence presented using the 
other metrics as to the relatively greater benefits of the BART 
alternative over BART. Based on this weight of evidence analysis of 
emission reductions and visibility improvement by the State (using the 
98th percentile metric) as complemented by the EPA's analysis of the 
ten highest impacted days and number of days impacted over 0.5 dv and 
1.0 dv, we propose to approve the determination by the State that the 
BART alternative achieves greater reasonable progress than BART under 
40 CFR 51.308(e)(2)(i)(E).
---------------------------------------------------------------------------

    \76\ 71 FR 60622 (October 13, 2006).
---------------------------------------------------------------------------

C. Requirement That Emission Reductions Take Place During the Period of 
the First Long-Term Strategy

    Pursuant to 40 CFR 51.308(e)(2)(iii), the State must ensure that 
all necessary emission reductions take place during the period of the 
first long-term strategy for regional haze, i.e. the first regional 
haze implementation period for Arkansas. To meet this requirement, the 
State must provide a detailed description of the alternative measure, 
including schedules for

[[Page 14861]]

implementation, the emission reductions required by the program, all 
necessary administrative and technical procedures for implementing the 
program, rules for accounting and monitoring emissions, and procedures 
for enforcement.
    While the BART alternative emission limits became enforceable by 
the State immediately upon issuance of a minor modification letter sent 
by the State to Domtar on February 28, 2019,\77\ the State notes in its 
Phase III SIP revision that Domtar provided documentation demonstrating 
that Power Boilers No. 1 and 2 have actually been operating at emission 
levels below the BART alternative emission limits since December 2016. 
This documentation included a letter dated December 20, 2018, submitted 
to ADEQ by Domtar,\78\ providing emissions data for Power Boilers No. 1 
and 2 from December 2016 to November 2018. The letter noted that 
because Power Boiler No. 1 has been in standby mode, it has emitted 
zero emissions since early 2016. The letter also provided continuous 
emissions monitoring system (CEMS) daily average and thirty-day rolling 
average emissions data for SO2 and NOX for Power 
Boiler No. 2 from December 1, 2016 through November 30, 2018. Based on 
this CEMS data (see Table 13), the highest thirty-day rolling averages 
for Power Boiler No. 2 were found to be 294 pph SO2 and 179 
pph NOX, which are below the BART alternative emission 
limits of 435 pph SO2 and 293 pph NOX. The 
December 20, 2018 letter explained that compliance with the 
PM10 BART alternative limit for Power Boiler No. 2 is 
demonstrated via compliance with the Boiler MACT. Based on previous 
compliance stack testing results conducted by Domtar in January 2016, 
PM10 emissions for Power Boiler No. 2 are equal to 34 pph 
PM10,\79\ which is below the BART alternative 
PM10 emission limit of 81.6 pph PM10.\80\ Based 
on this demonstration, we are proposing to find that Power Boilers No. 
1 and No. 2 at the Ashdown Mill satisfy the timing requirements of 40 
CFR 51.308(e) that the necessary emission reductions associated with 
the BART alternative occur during the first long-term strategy for 
regional haze.
---------------------------------------------------------------------------

    \77\ See Minor Modification Letter entitled, ``Application for 
Minor Modification Determination of Qualifying Minor Modification,'' 
included with the SIP revision and in the docket for this action.
    \78\ See letter from Domtar to ADEQ entitled, ``Demonstration of 
Compliance with Proposed BART Alternative,'' included with the SIP 
revision documenting compliance with the Phase III SIP emission 
limits.
    \79\ Based on the January 2016 stack testing, it was found that 
the actual PM10 emissions from Power Boiler No. 2 are 
0.059 lb/MMBtu (thirteen percent of the MACT standard of 0.44 lb/
MMBtu), which Domtar estimated to equal 34 pph based on a heat input 
of 569 MMBtu/hr during testing.
    \80\ See information provided in letters dated December 20, 
2018, and January 19, 2017, submitted by Domtar to ADEQ. These 
letters can be found in the ``Documentation of Compliance with Phase 
III SIP Emission Limits'' section of the Arkansas Regional Haze 
Phase III SIP revision.

           Table 13--Actual Emissions for Power Boiler No. 2 From December 2016 Through November 2018
----------------------------------------------------------------------------------------------------------------
                                                                    Emission rates, (pph) (based on maximum of
                                                                           thirty-day rolling averages)
                              Date                               -----------------------------------------------
                                                                        SO2             NOX            PM10
----------------------------------------------------------------------------------------------------------------
December 2016 through November 2018.............................      294 (-141)      179 (-114)      34 (-47.6)
----------------------------------------------------------------------------------------------------------------
* The numbers in parentheses indicate an increase (+) or decrease (-) in emissions from the BART alternative
  rates of 435 pph SO2; 293 pph NOX; and 81.6 pph PM10.

    Domtar submitted additional letters to ADEQ containing CEMS 
emission data from January 2018 to April 2019.\81\ This CEMS data 
demonstrates continued compliance for Power Boilers No. 1 and 2 by 
showing emission levels below the BART alternative emission limits 
beyond 2018 (see Table 14). Domtar noted that Power Boiler No. 1 
continued to be in standby mode and that its emissions have continued 
to be zero since early 2016. The Domtar letters also noted that the 
CEMS daily average and thirty-day rolling average emissions for 
SO2 and NOX were below the BART alternative 
limits for each month from January 2018 to April 2019. Additionally, 
based on the previous January 2016 Boiler MACT stack testing results, 
actual PM10 emissions from Power Boiler No. 2 were 
conservatively estimated to be 48 pph PM10, which is below 
the BART alternative emission limit of 81.6 pph PM10 for 
Power Boiler No. 2.\82\
---------------------------------------------------------------------------

    \81\ See letters from Domtar to ADEQ dated February 21, 2019; 
March 15, 2019; April 16, 2019; and May 16, 2019. These letters can 
be found in the ``Documentation of Compliance with Phase III SIP 
Emission Limits'' section of the Arkansas Regional Haze Phase III 
SIP revision.
    \82\ The PM10 emission rates were based on the 0.059 
lb/MMBtu stack testing result (thirteen percent of the MACT 
standard, 0.44 lb/MMBtu) and a maximum heat input capacity of the 
boiler of 820 MMBtu/hr.

                Table 14--Actual Emissions for Power Boiler No. 2 From January 2019 to April 2019
----------------------------------------------------------------------------------------------------------------
                                                                   Emission rates, (pph) * (based on maximum of
                                                                           thirty-day rolling averages)
                              Date                               -----------------------------------------------
                                                                        SO2             NOX            PM10
----------------------------------------------------------------------------------------------------------------
January 2019....................................................      280 (-155)      170 (-123)      48 (-33.6)
February 2019...................................................      305 (-130)      178 (-115)      48 (-33.6)
March 2019......................................................      270 (-165)      153 (-140)      48 (-33.6)
April 2019......................................................      250 (-185)      137 (-156)      48 (-33.6)
----------------------------------------------------------------------------------------------------------------
* The numbers in parentheses indicate an increase (+) or decrease (-) in emissions from the BART alternative
  rates of 435 pph SO2; 293 pph NOX; and 81.6 pph PM10.

[[Page 14862]]

    We propose to conclude that the State has adequately addressed the 
applicable provisions under 40 CFR 51.308(e)(2)(iii) to ensure all 
reductions take place during the period of the first long-term 
strategy.

D. Demonstration That Emission Reductions From Alternative Measure Will 
Be Surplus

    Pursuant to 40 CFR 51.308(e)(2)(iv), the SIP must demonstrate that 
the emission reductions resulting from the alternative measure will be 
surplus to those reductions resulting from measures adopted to meet 
requirements of the CAA as of the baseline date of the SIP. When 
promulgating this requirement in 1999, the EPA explained that emission 
reductions must be ``surplus to other Federal requirements as of the 
baseline date of the SIP, that is, the date of the emission inventories 
on which the SIP relies.'' \83\ The baseline date for the 2008 Arkansas 
Regional Haze SIP emission inventory was previously established as 2002 
during SIP planning stages for the first implementation period.\84\ In 
the Arkansas Regional Haze Phase III SIP revision, ADEQ states that the 
BART alternative emission reductions are based on operational changes 
for Domtar and are surplus to reductions as of the baseline of the 2008 
Arkansas Regional Haze SIP. We agree with the State that the emission 
reductions required by the State's BART alternative are additional and 
will not result in double-counting of reductions from other Federal 
requirements since they will occur after the original 2002 emission 
inventory. Therefore, we propose to find that the Domtar BART 
alternative meets the requirements of 40 CFR 51.308(e)(2)(iv).
---------------------------------------------------------------------------

    \83\ See 64 FR 35714, 35742 (July 1, 1999); see also 70 FR 
39104, 39143 (July 6, 2005).
    \84\ See Memorandum from Lydia Wegman and Peter Tsirigotis, 2002 
Base Year Emission Inventory SIP Planning: 8-hr Ozone, 
PM2.5, and Regional Haze Programs, November 8, 2002.
---------------------------------------------------------------------------

E. Implementation of the BART Alternative Through Permit Conditions

    The Arkansas Regional Haze Phase III SIP revision incorporates 
certain provisions of the permit that became effective August 1, 2019 
and includes all conditions for implementing the Domtar BART 
alternative and making it enforceable in practice.\85\ The emission 
limits became enforceable by the State immediately upon issuance of the 
minor modification letter sent to Domtar on February 28, 
2019.86 87 The final permit revision that became effective 
August 1, 2019 (0287-AOP-R22) includes plantwide conditions 32 through 
43 that contain enforceable emission limits for NOX, 
SO2, and PM10 (see Table 1) as well as compliance 
requirements for the power boilers. Compliance with SO2, 
NOX and PM10 emissions limits (0.5, 191.1, and 
5.2 pph, respectively) for Power Boiler No. 1 is based on a thirty-day 
boiler operating day rolling average \88\ based on natural gas fuel 
usage records and the following AP-42 emission factors: 0.6 lb 
SO2/MMscf, 280 lb NOX/MMscf, and 7.6 lb 
PM10/MMscf (conditions 32 and 33).\89\ In the event Power 
Boiler No. 1 is permanently retired, the BART alternative limits and 
conditions applicable to Power Boiler No. 1 shall be satisfied by the 
permanent retirement and ADEQ receipt of a disconnection notice 
(condition 34). Records showing compliance for Power Boiler No. 1 are 
required and shall be retained for at least five years and made 
available to ADEQ or EPA upon request (condition 36). Compliance with 
SO2, NOX, and PM10 emission limits 
(435, 293, and 81.6 pph, respectively) for Power Boiler No. 2 is based 
on a thirty-day boiler operating day rolling average (condition 37). 
Compliance with the SO2 and NOX emission limits 
for Power Boiler No. 2 is based on CEMS data that is subject to 40 CFR 
part 60, as amended (condition 38). Since Power Boiler No. 2 is subject 
to 40 CFR part 63 subpart DDDDD, the applicable PM10 
compliance demonstration requirements under the Boiler MACT shall be 
utilized to demonstrate compliance for PM10 emissions 
(condition 41). If Power Boiler No. 2 switches to natural gas 
combustion, the applicable natural gas AP-42 emission factors of 0.6 lb 
SO2/MMscf, 280 lb NOX/MMscf, and 7.6 lb 
PM10/MMscf in conjunction with natural gas fuel usage 
records (condition 40) shall be used to demonstrate compliance with the 
BART emission limits. In the event Power Boiler No. 2 is permanently 
retired, the BART alternative limits and conditions applicable to Power 
Boiler No. 2 shall be satisfied by the permanent retirement and ADEQ 
receipt of a disconnection notice (condition 39).\90\ Records showing 
compliance for Power Boiler No. 2 are required and shall be retained 
for at least five years and made available to ADEQ or EPA upon request 
(condition 43). With the EPA concurrence with the State, Domtar may 
request alternative sampling or monitoring methods that are equivalent 
to the methods specified in conditions 32 to 35 for Power Boiler No. 1, 
and in conditions 37 to 41 for Power Boiler No. 2 (conditions 35 and 
42). We propose to approve these specific plantwide permit provisions 
for the BART alternative as source-specific SIP requirements.
---------------------------------------------------------------------------

    \85\ See Plantwide Conditions #32 to #43 from permit #0287-AOP-
R22. For compliance with the CAA Regional Haze Program's 
requirements for the first planning period, the No. 1 and 2 Power 
Boilers are subject-to-BART alternative measures consistent with 40 
CFR 51.308. These Plantwide Conditions state that the terms and 
conditions of the BART alternative measures are to be submitted to 
the EPA for approval as part of the Arkansas SIP, which ADEQ has 
done through submittal of the Phase III SIP revision. The Plantwide 
Conditions also state that upon initial EPA approval of the permit 
into the SIP, the permittee shall continue to be subject to the 
conditions as approved into the SIP even if the conditions are 
revised as part of a permit amendment until such time as the EPA 
approves any revised conditions into the SIP. The permittee shall 
remain subject to both the initial SIP-approved conditions and the 
revised conditions, until the EPA approves the revised conditions.
    \86\ See Minor Modification Letter entitled, ``Application for 
Minor Modification Determination of Qualifying Minor Modification,'' 
included with the SIP revision and in the docket for this action.
    \87\ Under APCEC Reg. 26.1007, ``a source may make the change 
proposed in its minor permit modification application upon receipt 
of written notification from the Department.'' After the source 
makes the proposed change and until the Department takes action on 
the minor modification application, the source ``must comply with 
both the applicable requirements governing the change and the 
proposed permit terms and conditions.''
    \88\ A thirty-day boiler operating day rolling average is 
defined as the arithmetic average of thirty consecutive daily values 
in which there is any hour of operation, and where each daily value 
is generated by summing the pounds of pollutant for that day and 
dividing the total by the sum of the hours the boiler was operating 
that day. A day is from 6 a.m. one calendar day to 6 a.m. the 
following calendar day.
    \89\ AP-42, Compilation of Air Pollutant Emission Factors, has 
been published since 1972 as the primary compilation of the EPA's 
emission factor information. It contains emission factors and 
process information for more than 200 air pollution source 
categories. The emission factors have been developed and compiled 
from source test data, material balance studies, and engineering 
estimates. The Fifth Edition of AP-42 was published in January 1995. 
Since then, the EPA has published supplements and updates to the 
fifteen chapters available in Volume I, Stationary Point and Area 
Sources.
    \90\ This is a notice to ADEQ that indicates that a unit is 
being taken permanently out-of-service.
---------------------------------------------------------------------------

F. EPA's Conclusion on Arkansas' BART Alternative Determination for 
Domtar

    We are proposing to find that the State submitted as part of their 
Arkansas Regional Haze Phase III SIP revision all of the required plan 
elements under 40 CFR 51.308(e)(2) and documentation of all required 
analyses for the BART alternative determination. We are proposing to 
find that the State demonstrated through a clear weight of evidence 
approach that the BART alternative achieves greater reasonable progress 
than would be achieved through the installation and operation of BART. 
The State also established that all necessary emission reductions took 
place during the period of the first long-term strategy, and that no 
double-

[[Page 14863]]

counting of emission reductions would occur but would be surplus to 
those from other Federal requirements as of 2002, the baseline date for 
the 2008 SIP.\91\ The BART alternative limits in this proposed action 
are enforceable by the State through certain provisions in Permit No. 
0287-AOP-R22. These specific permit conditions have been submitted as 
part of the Arkansas Regional Haze Phase III SIP submittal as source-
specific SIP requirements.
---------------------------------------------------------------------------

    \91\ The emission limits and estimated annual emission 
reductions under the BART alternative are presented in Tables 1 and 
6, respectively.
---------------------------------------------------------------------------

    We, therefore, propose to approve the BART alternative 
demonstration for Domtar as meeting the applicable requirements under 
40 CFR 51.308(e)(2). We also propose to approve the specific plantwide 
permit provisions for the BART alternative as source-specific SIP 
requirements. We propose to withdraw the SO2, 
NOX, and PM10 BART emission limits in the FIP and 
associated compliance requirements for Domtar Power Boiler Nos. 1 and 
2; and replace them with the State's SO2, NOX, 
and PM10 BART alternative emission limitations and 
compliance requirements in the Arkansas Regional Haze Phase III SIP 
revision. In addition, we propose to approve the State's replacement of 
the current PM10 BART determination of 0.07 lb/MMBtu that 
was approved for Power Boiler No. 1 in our March 2012 final action on 
the 2008 Arkansas Regional Haze SIP with the PM10 BART 
alternative limit.

G. Consultation With States and Federal Land Managers

    The Regional Haze Rule requires states to provide the designated 
FLMs with an opportunity for consultation at least sixty days prior to 
holding any public hearing on a SIP revision for regional haze for the 
first implementation period. Arkansas sent emails to the FLMs on August 
9, 2018, providing notification of the proposed SIP revision and 
electronic access to the draft SIP revision and related documents. The 
FLMs did not provide comments to Arkansas on the proposed SIP revision.
    The Regional Haze Rule at section 51.308(d)(3)(i) also provides 
that if a state has emissions that are reasonably anticipated to 
contribute to visibility impairment in a Class I area located in 
another state, the state must consult with the other state(s) in order 
to develop coordinated emission management strategies. Since Missouri 
has two Class I areas impacted by Arkansas sources, Arkansas sent an 
email to the Missouri Department of Natural Resources (MDNR) on August 
9, 2018, providing notification of the proposed SIP revision and 
electronic access to the draft and related documents. Missouri did not 
provide comments to Arkansas on the proposed SIP revision.
    We propose to find that Arkansas provided an opportunity for 
consultation to the FLMs and to Missouri for the proposed SIP revision, 
as required under section 51.308(i)(2) and 51.308(d)(3)(i).

III. Evaluation of Arkansas' Long-Term Strategy Provisions for Domtar 
Ashdown Mill

    We approved the majority of Arkansas' long-term strategy 
requirements in the 2012 final action on the 2008 Arkansas Regional 
Haze SIP. Because we disapproved some of ADEQ's BART determinations and 
disagreed with the calculated RPGs for Arkansas' two Class I areas in 
that action, we disapproved the corresponding emission limits and 
schedules of compliance section under 51.308(d)(3)(v)(C) since that 
section relies on the State having approved BART determinations and 
established RPGs as part of its long-term strategy. The 2016 FIP later 
established emission limits and included revised RPGs that became 
components of the long-term strategy for Arkansas' Class I areas. The 
EPA-approved Phase I and II SIP revisions (mentioned in section I.F of 
this action) replaced all of the 2016 FIP BART determinations with 
enforceable SIP measures except for the requirements pertaining to the 
two Domtar power boilers. With our approval of the Phase II SIP 
revision, all of the elements of the long-term strategy were approved 
except for those pertaining to Domtar. ADEQ did not revise the long-
term strategy elements in the Arkansas Regional Haze Phase III SIP 
submittal except for inclusion of enforceable emission limitations and 
compliance schedules for Domtar. ADEQ is addressing those remaining FIP 
BART requirements for Domtar with the BART alternative provisions in 
section II of this action. Based upon this, we propose to approve the 
emission limits and schedules of compliance section under 
51.308(d)(3)(v)(C) pertaining to Domtar in the Arkansas Regional Haze 
Phase III SIP submittal. Pending final approval of the BART alternative 
requirements for the Domtar Ashdown Mill being addressed in this 
action, ADEQ will have satisfied all long-term strategy requirements 
under section 51.308(d)(3) for the first implementation period.

IV. Evaluation of Reasonable Progress Requirements for Domtar Ashdown 
Mill

    On September 27, 2019, in our final action on the Arkansas Regional 
Haze SO2 and PM SIP revision, we determined that Arkansas 
had fully addressed the reasonable progress requirements under section 
51.308(d)(1) for the first implementation period and we agreed with the 
State's revised RPGs for its Class I areas. In that action, we noted 
that the 2016 FIP BART requirements for Domtar were still in place but 
we agreed with the State that as long as those requirements continue to 
be addressed by the measures in the FIP, nothing further is needed to 
satisfy the reasonable progress requirements for the first 
implementation period. We acknowledged in that action that we would 
assess the August 13, 2019, Arkansas Regional Haze Phase III SIP 
submittal to address the regional haze requirements for Domtar and 
evaluate any conclusions drawn by ADEQ regarding the need to conduct a 
reasonable progress analysis for that facility. In addition, we stated 
that we would also assess the August 13, 2019, submittal to see if 
changes are needed with respect to the revised RPGs, based on any 
differences between the SIP and FIP-based measures for Domtar.
    In the Arkansas Regional Haze Phase III SIP submittal, which we are 
proposing to approve in this action, the BART alternative analysis 
performed for the Domtar power boilers is based, in part, on an 
assessment of the same factors that must be addressed in a reasonable 
progress analysis establishing the RPGs.\92\ The 2007 guidance for 
reasonable progress explains that, ``it is reasonable to conclude that 
any control requirements imposed in the BART determination also satisfy 
the RPG-related requirements for source review in the first RPG 
planning period. Hence, you may conclude that no additional emission 
controls are necessary for these sources in the first planning 
period.'' \93\ This rationale applies for Domtar since a previous BART 
determination for Domtar was

[[Page 14864]]

developed in the 2016 FIP. That BART analysis was compared to the BART 
alternative controls in the Arkansas Regional Haze Phase III SIP 
submittal. As detailed in Section II above, the BART alternative 
measures for Domtar result in greater visibility improvement than the 
BART requirements in the FIP and the previously approved BART 
PM10 limit for Power Boiler No. 1. We propose to agree with 
ADEQ's conclusion in the Arkansas Regional Haze Phase III submittal 
that nothing further is needed to satisfy the reasonable progress 
requirements for the first implementation period.
---------------------------------------------------------------------------

    \92\ See 40 CFR 51.308(d). The State must evaluate and determine 
the emission reduction measures that are necessary to make 
reasonable progress by considering the costs of compliance, the time 
necessary for compliance, the energy and non-air quality 
environmental impacts of compliance, and the remaining useful life 
of any potentially affected anthropogenic source of visibility 
impairment.
    \93\ Guidance for Setting Reasonable Progress Goals Under the 
Regional Haze Program, June 1, 2007, memorandum from William L. 
Wehrum, Acting Assistant Administrator for Air and Radiation, to EPA 
Regional Administrators, EPA Regions 1-10 (pp. 4-2, 4-3, and 5-1).
---------------------------------------------------------------------------

    ADEQ also provided calculations in the Arkansas Regional Haze Phase 
III SIP submittal, estimating the effect of emission reductions from 
the BART alternative on the 2018 revised RPGs for Caney Creek and Upper 
Buffalo.\94\ ADEQ scaled CENRAP's CAMx \95\ 2018 modeled light 
extinction components from Arkansas sources for 
SO4\2\- and NO3-in 
proportion to emission reductions anticipated for SO2 and 
NOX from the SIP controls in the previously approved Phase I 
and Phase II SIPs, as wells as the BART alternative controls for 
Domtar. The estimation of the revised 2018 RPGs in the Phase II SIP 
accounted for emission reductions anticipated under the FIP for Domtar, 
and the emission reductions due to the controls in the Phase I and 
Phase II SIP revisions.\96\ In our final action on the Arkansas 
Regional Haze SO2 and PM SIP revision, we agreed with the 
State's revised RPGs for its Class I areas.\97\ We note that based on 
IMPROVE monitoring data, both Caney Creek and Upper Buffalo Wilderness 
areas are achieving greater visibility improvement than the revised 
2018 RPGs.\98\ ADEQ estimated that the emission reductions from the 
BART alternative would negligibly impact the revised 2018 RPGs 
established in the Phase II SIP revision for the twenty percent worst 
days. As a result, ADEQ did not make revisions to the 2018 RPGs for its 
Class I areas in the Arkansas Regional Haze Phase III SIP submittal. 
Power Boilers No. 1 and 2 have been operating at emission levels below 
the BART alternative emission limits since December 2016 (as discussed 
in section II.C), so emission reductions from Domtar are reflected in 
the current monitoring data which shows that current visibility 
conditions are better than the revised 2018 RPGs. We propose to agree 
with ADEQ that the BART alternative for Domtar would have only a minor 
impact on the 2018 RPGs previously established in the Phase II SIP 
revision and that there is no need to revise them in conjunction with 
this action.
---------------------------------------------------------------------------

    \94\ See Excel spreadsheet ``Phase III SIP Rev RPG.xlsx,'' which 
is part of the Arkansas Regional Haze Phase III SIP revision and can 
be found in the docket for this proposed rulemaking.
    \95\ Comprehensive Air Quality Model with extensions, i.e. CAMx, 
is a multi-scale, three-dimensional photochemical grid model.
    \96\ See appendix F6 of the Arkansas Regional Haze 
SO2 and PM SIP revision.
    \97\ The 2018 RPGs for Caney Creek and Upper Buffalo were 
revised slightly downward from the 2008 SIP RPGs to 22.47 dv and 
22.51 dv for the twenty percent worst days.
    \98\ See Figures 11 and 12 of the Arkansas Regional Haze 
SO2 and PM SIP revision (pages 50-52).
---------------------------------------------------------------------------

    We propose to approve the reasonable progress components under 40 
CFR 51.308(d)(1) relating to Domtar Power Boilers No. 1 and 2. With the 
approved Arkansas Regional Haze SO2 and PM SIP revision 
requirements and the Arkansas Regional Haze Phase III BART alternative 
requirements being addressed in this proposed action (pending final 
approval), Arkansas will have addressed all reasonable progress 
requirements under section 51.308(d)(1) and will have a fully-approved 
regional haze SIP for the first implementation period.

V. Evaluation of Arkansas Visibility Transport

    On October 4, 2019, the State submitted the Arkansas 2015 
O3 NAAQS Interstate Transport SIP revision to meet the 
requirements of CAA section 110(a)(2)(D) regarding interstate transport 
for the 2015 O3 NAAQS. In that proposed SIP submittal, 
Arkansas addressed the prong 4 visibility transport obligations in 
section 110(a)(2)(D)(i)(II) for the 2006 and 2012 PM2.5 
NAAQS; the 2008 and 2015 O3 NAAQS; the 2010 SO2 
NAAQS; and the 2010 NO2 NAAQS. We are proposing to approve 
these elements in this action. All other applicable Infrastructure SIP 
requirements for that SIP submission have been or will be addressed in 
separate rulemakings. On August 10, 2018, the State also submitted a 
discussion on visibility transport in its Phase II Arkansas Regional 
Haze SO2 and PM SIP revision. In this action, we are also 
proposing to approve that portion of the Phase II SIP submittal as 
supplemented by the 2015 O3 NAAQS Interstate Transport SIP 
revision.
    The EPA most recently issued guidance for infrastructure SIPs on 
September 13, 2013. The 2013 guidance lays out how a state's 
infrastructure SIP submission may satisfy prong 4.\99\ The guidance 
indicates that one way that a state can satisfy prong 4 requirements is 
with a fully-approved regional haze SIP that meets the requirements 
found in 40 CFR 51.308 or 309. Requirements under 40 CFR 
51.308(d)(3)(ii) specifically require that a state participating in a 
regional planning process include all measures needed to achieve its 
apportionment of emission reduction obligations agreed upon through 
that process. A fully-approved regional haze plan will ensure that 
emissions from sources under an air agency's jurisdiction are not 
interfering with measures required to be included in other air 
agencies' plans to protect visibility. The 2009 guidance,\100\ which 
the 2013 guidance built upon, explained how the development of regional 
haze SIPs was intended to occur in a collaborative environment among 
the states. It was envisioned that through this process states would 
coordinate emission controls to protect visibility and take action to 
achieve the emission reductions relied upon by other states in their 
reasonable progress demonstrations.
---------------------------------------------------------------------------

    \99\ See ``Guidance on Infrastructure State Implementation Plan 
(SIP) Elements under Clean Air Act Sections 110(a)(1) and 
110(a)(2)'' by Stephen D. Page (Sept. 13, 2013).
    \100\ See ``Guidance on SIP Elements Required Under sections 
110(a)(1) and (2) for the 2006 24-Hour Fine Particle 
(PM2.5) National Ambient Air Quality Standards (NAAQS)'' 
by William T. Harnett (September 25, 2009).
---------------------------------------------------------------------------

    Alternatively, the 2013 guidance explains that in the absence of a 
fully-approved regional haze SIP, a state may meet the prong 4 
requirement through a demonstration showing that emissions within its 
jurisdiction do not interfere with another air agencies' plans to 
protect visibility. According to the guidance, such an infrastructure 
SIP submission would need to include an analysis of measures that limit 
visibility-impairing pollutants and ensure that the reductions conform 
with any mutually agreed upon regional haze RPGs for Class I areas in 
other states.

A. Fully-Approved Regional Haze SIP to Meet Visibility Transport 
Requirement

    The State indicated in the October 4, 2019, Arkansas 2015 
O3 NAAQS Interstate Transport SIP submittal that a fully-
approved regional haze SIP will meet the prong 4 visibility transport 
requirement of CAA section 110(a)(2)(D)(i)(II). The Arkansas Regional 
Haze NOX SIP revision (Phase I),\101\ the Arkansas Regional 
Haze SO2 and PM SIP revision (Phase II),\102\ and the 
Arkansas Regional Haze Phase III SIP revision, if finalized, together 
will fully address the deficiencies in the

[[Page 14865]]

2008 Arkansas Regional Haze SIP as identified in our March 12, 2012 
final action. If we take final action to approve the Phase III SIP 
submittal, Arkansas will have a fully-approved regional haze SIP for 
the first planning period. This will ensure that emissions from 
Arkansas will not interfere with measures required to be included in 
other air agencies' plans to protect visibility. We are, therefore, 
proposing to approve the CAA section 110(a)(2)(D)(i)(II) visibility 
transport elements included in the 2018 Arkansas Regional Haze 
SO2 and PM SIP revision, as supplemented in the Arkansas 
2015 O3 NAAQS Interstate Transport SIP revision. These 
revisions address prong 4 for the following NAAQS: The 2006 24-hour 
PM2.5 NAAQS; the 2012 annual PM2.5 NAAQS; the 
2008 and 2015 eight-hour O3 NAAQS; the 2010 one-hour 
NO2 NAAQS; and the 2010 one-hour SO2 NAAQS. 
Finalization of the Arkansas prong 4 visibility transport elements in 
these submittals on the basis of a fully-approved SIP is contingent 
upon final approval of the Arkansas Regional Haze Phase III SIP 
submittal.
---------------------------------------------------------------------------

    \101\ Final action approved on February 12, 2018 (83 FR 5927).
    \102\ Final action approved on September 27, 2019 (84 FR 51033). 
Proposed approval on November 30, 2018 (83 FR 62204).
---------------------------------------------------------------------------

B. Alternate Demonstration to Meet Visibility Transport Requirement

    As stated previously, the 2013 guidance provides that in the 
absence of a fully-approved regional haze SIP, a state may meet the 
prong 4 requirement through a demonstration showing that emissions 
within its jurisdiction do not interfere with other air agencies' plans 
to protect visibility. ADEQ provided such a demonstration in the 
Arkansas 2015 O3 NAAQS Interstate Transport SIP submittal 
that addresses the requirements of CAA section 110(a)(2)(D)(i)(II) for 
the six NAAQS previously mentioned. Arkansas documented its 
apportionment of emission reduction obligations needed at affected 
Class I areas in other states and provided a demonstration that the SIP 
includes approved federally enforceable measures that contribute to 
achieving the 2018 RPGs set for those areas.
    Through collaboration with the Central Regional Air Planning 
Association (CENRAP),\103\ ADEQ worked with other central states to 
assess state-by-state contributions to visibility impairment in 
specific Class I areas affected by emissions from Arkansas. ADEQ used 
CENRAP as the main vehicle for developing its 2008 regional haze SIP 
for the first implementation period.\104\ CENRAP developed regional 
photochemical modeling results, visibility projections for 2018, and 
source apportionment modeling to assist in identifying contributions to 
visibility impairment. Two Class I areas outside Arkansas' borders, 
Hercules-Glades Wilderness and Mingo National Wildlife Refuge in 
Missouri, were identified as being impacted by emissions generated from 
within Arkansas.\105\ Based on the emission assessments and modeled 
visibility impacts, the EPA agreed with the 2018 RPGs developed by 
Missouri that account for Arkansas' emission contributions to those two 
Class I areas.\106\
---------------------------------------------------------------------------

    \103\ The CENRAP is a collaborative effort of tribal 
governments, state governments and various federal agencies 
representing the central states (Texas, Oklahoma, Louisiana, 
Arkansas, Kansas, Missouri, Nebraska, Iowa, Minnesota; and tribal 
governments included in these states) that provided technical and 
policy tools for the central states and tribes to comply with the 
EPA's Regional Haze regulations.
    \104\ 77 FR 14604 (March 12, 2012).
    \105\ See 2008 Arkansas Regional Haze SIP (page 45).
    \106\ 77 FR 38007 (June 26, 2012).
---------------------------------------------------------------------------

    In the Arkansas 2015 O3 NAAQS Interstate Transport SIP, 
ADEQ presented the CENRAP modeled 2018 projected contributions to 
visibility impairment at Missouri's two Class I areas that included 
particulate source apportionment (PSAT) results. CENRAP contracted with 
ENVIRON International and the University of California at Riverside 
(Collectively ``Environ/UCR'') to perform the emissions and air quality 
modeling. The CENRAP modeling projected that Arkansas emissions 
contribute 7.6 percent of the total light extinction at Hercules-Glades 
and 4.4 percent of the total light extinction at Mingo.\107\ Based on 
the projected CENRAP modeling results, ADEQ noted that both Hercules-
Glades and Mingo were expected to achieve visibility improvements 
greater than or equal to what would be achieved under a uniform rate of 
progress by 2018.\108\ The modeling included some emission reductions 
anticipated from BART controls at EGUs in Arkansas and other states. 
Missouri set its RPGs based on these 2018 visibility projections by 
CENRAP and did not request Arkansas to include any specific measures 
beyond the anticipated BART reductions included as inputs in the 
projected modeling.\109\ ADEQ met its share of emission reduction 
obligations that Missouri agreed to and relied on in establishing their 
own RPGs by implementing BART emission limits for EGUs in the Phase I 
and II SIP submittals that were approved by the EPA. ADEQ summarized 
those measures in the Arkansas 2015 O3 NAAQS Interstate 
Transport SIP and then compared the SIP-controlled emissions to what 
was originally projected. The State demonstrated that its emission 
reduction obligations have been met because the EPA-approved Phase I 
and II SIP revision controls achieve greater emission reductions than 
Arkansas had committed to by reducing the emissions to less than the 
projections used to develop Missouri's 2018 RPGs for Hercules-Glades 
and Mingo for the first implementation period.\110\
---------------------------------------------------------------------------

    \107\ See Figures 69 to 72 from the Arkansas 2015 O3 
NAAQS Interstate Transport SIP submittal (pages 98-102).
    \108\ Environ International Corporation and University of 
California at Riverside (2007). ``Technical Support Document for 
CENRAP Emissions and Air Quality Modeling to Support Regional Haze 
State Implementation Plans.''
    \109\ See Alpine Geophysics, LLC (2006) ``CENRAP Regional Haze 
Control Strategy Analysis Plan.''
    \110\ See Tables 15 and 16 from the Arkansas 2015 O3 
NAAQS Interstate Transport SIP submittal (page 103).
---------------------------------------------------------------------------

    Specifically, the Phase I SIP revision replaced source-specific NOx 
emission limits for EGUs with reliance on CSAPR for O3 
season NOX as an alternative to BART. The CSAPR update 
revised the O3 season NOX budget for Arkansas 
units from 15,110 tons NOX in 2015 to 12,048 tons 
NOX (11,808 allocated to existing EGUs) in 2017. The budget 
was further reduced to 9,210 tons NOX (9,025 allocated to 
existing EGUs) in 2018 and beyond, which is 5,164 tons less than the 
2014 to 2016 O3 season average. When comparing the 2018 
O3 season emissions, Arkansas totaled 10,952 tons 
NOX, which is 2,912 tons below the 13,865 tons projected for 
EGUs. ADEQ noted that three of the Arkansas subject-to-BART EGUs, White 
Bluff units 1 and 2 and Flint Creek, have recently installed low 
NOX burners with separated overfire air to reduce 
NOX emissions. The Phase II SIP revision included measures 
to address all remaining disapproved portions of the 2008 Arkansas 
Regional Haze SIP, with the exception of those portions specifically 
pertaining to the Domtar Ashdown Mill, the only non-EGU subject-to-BART 
facility in Arkansas. The Phase II SIP revision controls are estimated 
to reduce the total annual SO2 emissions from Arkansas 
subject-to-BART sources to 18,699 tons lower than what was assumed in 
the 2018 projections (see Table 15). We are proposing to find that the 
controlled emission rates from each of these SIP revisions show that 
Arkansas has obtained its share of the emission reductions agreed upon 
and necessary to achieve the 2018 RPGs set by

[[Page 14866]]

Missouri at Hercules-Glades and Mingo areas for the first planning 
period.

            Table 15--2018 Projected SO2 Emissions Compared to Phase II Controlled EGU SO2 Emissions
                                                     [Tons]
----------------------------------------------------------------------------------------------------------------
                                                                                                      Annual
                                                                  2018 projected      Annual         emission
                    Subject-to-BART facility                         emissions      controlled      reductions
                                                                       \111\         emissions      beyond the
                                                                                       \112\        projections
----------------------------------------------------------------------------------------------------------------
Entergy Arkansas White Bluff *..................................          45,970    29,175 \113\          16,795
Arkansas Electric Cooperatives John L. McClellan................              <1              75             -75
Southwestern Power Company Flint Creek..........................           2,896             907           1,989
Arkansas Electric Cooperatives Carl E. Baily Generating Station.               0              10             -10
Entergy Arkansas Lake Catherine.................................               0              <1               0
                                                                 -----------------------------------------------
    Total.......................................................          48,866          30,167          18,699
----------------------------------------------------------------------------------------------------------------
* There are no source-specific NOX measures for Arkansas subject-to-BART EGUs, except for a limit for White
  Bluff Auxiliary boiler. The Phase I SIP revision replaced source-specific NOx emission limits for EGUs in the
  FIP with reliance on CSAPR for O3 season NOX as an alternative to BART.

    The 2018 emission projections did not assume any emission 
reductions from Domtar. Therefore, Missouri did not rely on any 
reductions from the Domtar Ashdown Mill when calculating 2018 RPGs for 
Mingo and Hercules-Glades. Thus, Arkansas has demonstrated that it is 
meeting its visibility transport obligations even without the BART 
alternative emission limits for the Domtar Ashdown Mill in the Phase 
III SIP revision. The EPA is adding Table 16 to show that additional 
SO2 and NOX emission reductions of 333 tpy and 
1,719 tpy, respectively, will occur from the Domtar BART alternative 
controls evaluated in section II of this proposed action.
---------------------------------------------------------------------------

    \111\ These values have been included in the spreadsheet that 
Arkansas adapted from a Reasonable Progress Goal scaling spreadsheet 
developed by EPA for use in determining the extent that changes in 
control requirements are anticipated to result in changes in 
visibility impairment on the twenty percent worst days for Arkansas 
Class I areas. This spreadsheet was included in the submittal by the 
State and is in the docket of this action. It can also be accessed 
at https://www.adeq.state.ar.us/air/planning/sip/pdfs/regional-haze/f.6-sip-rev-rpg-data-sheet.xlsx.
    \112\ Except for White Bluff Controlled Emission Rates, 
controlled emission rates can be found on the 2018 tab of the F.6 
SIP Rev RPG Data Sheet. (https://www.adeq.state.ar.us/air/planning/sip/pdfs/regionalhaze/f.6-sip-rev-rpg-data-sheet.xlsx).
    \113\ Entergy (2017) ``Updated BART Five-Factor Analysis for 
SO2 for Units 1 and 2'' for White Bluff Steam Electric 
Station (Available at https://www.adeq.state.ar.us/air/planning/sip/
pdfs/regional-haze/appendix-d-d.1_d.8.pdf).

                                    Table 16--Arkansas Phase III SIP Controlled Emissions for Domtar BART Alternative
                                                                         [Tons]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             2018 projected emissions        SIP-controlled emissions         SIP emission reduction
                Subject-to-BART facility                 -----------------------------------------------------------------------------------------------
                                                                SO2             NOX             SO2             NOX             SO2             NOX
--------------------------------------------------------------------------------------------------------------------------------------------------------
Domtar Ashdown Mill.....................................           2,241           3,839           1,907           2,120             333           1,719
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The visibility improvement observed at the IMPROVE monitors by ADEQ 
in the Arkansas 2015 O3 NAAQS Interstate Transport SIP 
indicates that Missouri is achieving greater visibility improvement for 
Hercules-Glades and Mingo than Missouri's 2018 RPGs.\114\ The 2012 to 
2016 five-year rolling average of observed visibility impairment for 
the twenty percent haziest days at Hercules-Glades Wilderness Area is 
20.72 dv (2.34 dv below Missouri's 2018 RPG). The 2012 to 2016 five 
year-rolling average of observed visibility impairment for the twenty 
percent haziest days at Mingo National Wildlife Refuge is 22.34 dv 
(1.37 dv below Missouri's 2018 RPG goal).
---------------------------------------------------------------------------

    \114\ See Figures 73 and 74 of the Arkansas 2015 O3 
NAAQS Interstate Transport SIP submittal (pages 109-110).
---------------------------------------------------------------------------

C. EPA's Conclusion on Arkansas Visibility Transport

    We propose to approve the CAA section 110(a)(2)(D)(i)(II) 
visibility transport provisions included in the October 4, 2019, 
Arkansas 2015 O3 NAAQS Interstate Transport SIP revision for 
the 2006 24-hour PM2.5 NAAQS; the 2012 annual 
PM2.5 NAAQS; the 2008 and 2015 eight-hour O3 
NAAQS; the 2010 one-hour NO2 NAAQS; and the 2010 one-hour 
SO2 NAAQS on the basis that Arkansas will have a fully-
approved Regional Haze SIP once we finalize our proposed approval of 
the Arkansas Regional Haze Phase III SIP submittal. We also propose to 
approve the visibility transport portion of the August 8, 2018, Phase 
II SIP revision as supplemented by the October 4, 2019, Arkansas 2015 
O3 NAAQS Interstate Transport SIP submittal. The Arkansas 
Regional Haze NOX SIP revision, the Arkansas Regional Haze 
SO2 and PM SIP revision, and the Arkansas Regional Haze 
Phase III SIP revision (if approved) together fully address all 
deficiencies of the 2008 Arkansas Regional Haze SIP that were 
identified in our March 12, 2012, partial approval/disapproval action. 
A fully-approved regional haze plan will ensure that emissions from 
Arkansas will not interfere with measures required to be included in 
other air agencies' plans to protect visibility as required by CAA 
section 110(a)(2)(D)(i)(II). In addition, we propose to find that 
Arkansas has provided an adequate demonstration in the Arkansas 2015 
O3 NAAQS Interstate Transport SIP revision. The 
demonstration adequately shows that emissions within Arkansas' 
jurisdiction do not interfere with other air agencies'

[[Page 14867]]

plans to protect visibility because of EGU control measures in the EPA-
approved Phase I and Phase II SIP revisions.

VI. Evaluation of CAA Section 110(l)

    Under CAA Section 110(l), the EPA cannot approve a plan revision 
``if the revision would interfere with any applicable requirement 
concerning attainment and reasonable further progress, or any other 
applicable requirement of this chapter.'' \115\ Sections II, III, and 
IV of this action explain how the Arkansas Regional Haze Phase III SIP 
revision will comply with the requirements of the regional haze 
program. i.e., the other applicable requirements. Based on those 
conclusions, we propose to approve that the SIP revision will not 
interfere with the regional haze requirements in the CAA, including 
requirements pertaining to BART or reasonable progress under 40 CFR 
51.308(d) or (e). 40 CFR 51.308 details the required process for 
determining the appropriate emission limitations and compliance 
schedules for the regional haze program. As discussed in section II of 
this action, the State followed the prescribed process for determining 
the level of control required for the BART alternative for the Domtar 
Ashdown Mill and adequately supported its determination with analysis 
that meets the requirements under section 40 CFR 51.308(e)(2). In 
section III of this notice, we explain how ADEQ submitted emission 
limits and schedules of compliance pertaining to the Domtar Ashdown 
Mill that will satisfy all long-term strategy requirements under 
section 51.308(d)(3). In section IV of this notice, we discuss how ADEQ 
fully addressed the reasonable progress requirements under section 
51.308(d)(1) and we agree that no additional controls are necessary to 
achieve reasonable progress for the first implementation period. Our 
proposed approval of the Arkansas Regional Haze Phase III SIP revision 
is supported by our evaluation of the State's analytical conclusions 
and our rationale that the State has met the BART alternative and 
reasonable progress requirements for regional haze under the CAA as 
discussed in sections II, III, and IV of this action. For these 
reasons, we propose to find that our proposed approval of the Arkansas 
Regional Haze Phase III SIP revision and concurrent proposed withdrawal 
of the corresponding parts of the FIP do not interfere with the CAA 
requirements pertaining to BART or reasonable progress under 40 CFR 
51.308(d) or (e).
---------------------------------------------------------------------------

    \115\ Note that ``reasonable further progress'' as used in CAA 
section 110(l) is a reference to that term as defined in section 
301(a) (i.e., 42 U.S.C. 7501(a)), and as such means reductions 
required to attain the NAAQS set for criteria pollutants under 
section 109. This term as used in section 110(l) (and defined in 
section 301(a)) is not synonymous with ``reasonable progress'' as 
that term is used in the regional haze program. Instead, section 
110(l) provides that the EPA cannot approve plan revisions that 
interfere with regional haze requirements (including reasonable 
progress requirements) as far as they are ``other applicable 
requirements'' of the CAA.
---------------------------------------------------------------------------

    We also propose to find that approval of the Arkansas Regional Haze 
Phase III SIP revision and concurrent withdrawal of the corresponding 
parts of the FIP pertaining to Domtar will not interfere with 
attainment and maintenance of the NAAQS. The EPA interprets CAA section 
110(l) as applying to all NAAQS that are in effect, including those 
that have been promulgated but for which the EPA has not yet made 
designations. The EPA has concluded that 110(l) can be satisfied by 
demonstrating that substitute measures ensure that status quo air 
quality is preserved. However, 110(l) can also be satisfied by an air 
quality analysis demonstrating that any change in emissions will not 
interfere with any applicable requirement concerning attainment and 
reasonable further progress, or any other applicable CAA requirement. 
In general, the level of rigor needed for any CAA section 110(l) 
demonstration will vary depending on the nature of the revision, its 
potential impact on air quality and the air quality in the affected 
area. As discussed in sections II.B.3 and II.B.4 of this action,\116\ 
the BART alternative limits do not reduce SO2 emissions as 
much as the BART controls, however, all areas in Arkansas have been and 
are currently attaining all of the NAAQS, even though the BART controls 
for Domtar have not been implemented. Therefore, even though the BART 
alternative will not achieve the same level of emission reductions for 
SO2, this will not negatively impact current air quality, 
which is already sufficient to attain the SO2 NAAQS in 
Arkansas. Further, the State of Missouri did not rely on reductions 
from Domtar for its Regional Haze plans and the EPA is not aware of any 
other air quality analyses that rely on implementation of the BART 
requirements for Domtar in the FIP. Thus, the proposed withdrawal of 
the BART provisions in the FIP and replacement with the BART 
alternative requirements in the SIP will not negatively impact current 
air quality. While it is true that the FIP included more stringent 
SO2 emission limits for Domtar than the BART alternative, 
there is no evidence that withdrawal of the SO2 limits in 
the FIP for Domtar and the approval of the SO2 emission 
limits in the Phase III SIP revision will interfere with attainment of 
the SO2 NAAQS. In addition, as noted in section II.C of this 
action, Domtar provided documentation demonstrating that Power Boilers 
No. 1 and 2 have actually been operating at emission levels below the 
BART alternative emission limits since December 2016. At this time, and 
notwithstanding the fact that the FIP provisions have not gone into 
effect, the areas that would be potentially impacted by the increase in 
SO2 emissions allowed under the SIP revision as compared to 
the FIP are attaining the 2010 SO2 NAAQS. Based on an 
assessment of current air quality in the areas most affected by this 
SIP revision, we are concluding that the less stringent SO2 
emission limits in the Phase III SIP will not interfere with attainment 
of the NAAQS.
---------------------------------------------------------------------------

    \116\ See Tables 5 and 6 of this proposed action.
---------------------------------------------------------------------------

    Since SO42- is a precursor to PM, there is 
also a need to address whether withdrawal of the FIP and approval of 
the SIP revision will interfere with attainment of the PM NAAQS. There 
is no evidence that withdrawal of the SO2 limits in the FIP 
and the approval of the SO2 emission limits in the SIP 
revision will interfere with attainment of the PM NAAQS. At this time, 
and notwithstanding the fact that the FIP provisions have not gone into 
effect, the areas that would be potentially impacted by the increase in 
SO2 emissions are attaining the 2006 and 2012 
PM2.5 NAAQS.
    For these reasons we propose to conclude that the proposed approval 
of the Arkansas Regional Haze Phase III SIP revision and withdrawal of 
the remaining FIP will not interfere with attainment or maintenance of 
the NAAQS in Arkansas.

VII. Proposed Action

A. Arkansas Regional Haze Phase III SIP Submittal

    We propose to approve the Arkansas Regional Haze Phase III SIP 
revision (submitted August 13, 2019) as meeting the applicable regional 
haze BART alternative provisions set forth in 40 CFR 51.308(e)(2) for 
the Domtar Ashdown Mill. We propose to approve the reasonable progress 
components under 40 CFR 51.308(d)(1) relating to Domtar Power Boilers 
No. 1 and 2. With the approved Phase I and II SIP revision requirements 
and the Arkansas Regional Haze Phase III BART alternative requirements 
being addressed in this proposed action (pending final approval), 
Arkansas will have addressed all reasonable progress requirements

[[Page 14868]]

under section 51.308(d)(1) with a fully-approved regional haze SIP. We, 
therefore, propose to approve the emission limits and schedules of 
compliance section under 51.308(d)(3)(v)(3) pertaining to the Domtar 
Ashdown Mill in the August 13, 2019, submittal. Pending final approval 
of the BART alternative requirements for the Domtar Ashdown Mill being 
addressed in this action, ADEQ will have satisfied all long-term 
strategy requirements under section 51.308(d)(3). We agree with ADEQ's 
determination that the revised 2018 RPGs in the Phase II action do not 
need to be further revised. We propose to find that Arkansas has 
fulfilled its consultation requirements to FLMs and to Missouri for the 
proposed SIP submittal under sections 51.308(i)(2) and 51.308(d)(3)(i). 
Lastly, we propose to approve regional haze program-specific plantwide 
conditions 32 to 43 from section VI of permit revision #0287-AOP-R22 
into the SIP (effective August 1, 2019) for implementing the Domtar 
BART alternative. Specifically, these plantwide conditions of permit 
#0287-AOP-R22 are to be included in the SIP and approved as source-
specific SIP requirements for Power Boilers No. 1 and 2 are as follows: 
\117\
---------------------------------------------------------------------------

    \117\ For compliance with the CAA Regional Haze Program's 
requirements for the first planning period, Power Boilers No. 1 and 
2 are subject-to-BART alternative measures consistent with 40 CFR 
51.308. Upon final EPA approval of the permit into the SIP, the 
permittee continues to be subject to the conditions as approved into 
the SIP even if the conditions are revised as part of a permit 
amendment by ADEQ until such time as EPA approves any revised 
conditions into the SIP. The permittee shall remain subject to both 
the initial SIP-approved conditions and the revised SIP conditions, 
unless and until EPA approves the revised conditions.
---------------------------------------------------------------------------

     The SO2, NOX, and PM10 
emission limits in pph for Power Boiler No. 1 (condition 32) and Power 
Boiler No. 2 (condition 37) based on a thirty boiler operating day 
rolling average.
     Monitoring, recordkeeping, and reporting requirements for 
Power Boiler No. 1 (conditions 33 to 36) and Power Boiler No. 2 
(conditions 38 to 43).

B. FIP Withdrawal

    We propose to withdraw the remaining portions of the Arkansas 
Regional Haze FIP at 40 CFR 52.173 that impose SO2 and 
NOX BART requirements for Domtar Ashdown Mill Power Boiler 
No. 1; and SO2, NOX, and PM10 BART 
requirements for Domtar Ashdown Mill Power Boiler No. 2. We propose to 
replace these portions of the withdrawn FIP with our approval of the 
State's SO2, NOX, and PM10 BART 
alternative emission limitations in the Arkansas Regional Haze Phase 
III SIP submittal. In addition, we propose to approve the State's 
withdrawal of the current PM10 BART determination of 0.07 
lb/MMBtu for Power Boiler No. 1 in the 2008 Arkansas Regional Haze SIP, 
and propose to replace it with our approval of the PM10 BART 
alternative limit in the Arkansas Regional Haze Phase III SIP 
submittal.

C. Arkansas Visibility Transport

    We propose to approve the portion of the Arkansas 2015 
O3 NAAQS Interstate Transport SIP revision (submitted 
October 4, 2019) addressing CAA section 110(a)(2)(D)(i)(II) prong 4 
visibility transport provisions for Arkansas for the 2006 24-hour 
PM2.5 NAAQS; the 2012 annual PM2.5 NAAQS; the 
2008 and 2015 eight-hour O3 NAAQS; the 2010 one-hour 
NO2 NAAQS; and the 2010 one-hour SO2 NAAQS. We 
also propose to approve the visibility transport portion of the 2018 
Phase II SIP revision, as supplemented by the Arkansas 2015 
O3 NAAQS Interstate Transport SIP revision. The State's 
analysis in the Arkansas 2015 O3 NAAQS Interstate Transport 
SIP supersedes the visibility transport portion of the 2017 
infrastructure SIP. We propose to approve the prong 4 portions of these 
SIP submittals on the basis that Arkansas will have a fully-approved 
regional haze SIP if we finalize our proposed approval of the Arkansas 
Regional Haze Phase III SIP submittal. The Arkansas Regional Haze 
NOX SIP revision,\118\ the Arkansas Regional Haze 
SO2 and PM SIP revision,\119\ and the Arkansas Regional Haze 
Phase III SIP revision (if finalized) together will fully address the 
deficiencies of the 2008 Arkansas Regional Haze SIP that were 
identified in the March 12, 2012, partial approval/disapproval action. 
A fully-approved regional haze plan ensures that emissions from 
Arkansas sources do not interfere with measures required to be included 
in another air agencies' plans to protect visibility. As an alternative 
basis for approval of CAA section 110(a)(2)(D)(i)(II) prong 4 for these 
NAAQS, we propose to find that Arkansas has provided an adequate 
demonstration in the October 4, 2019 submittal showing that emissions 
within its jurisdiction do not interfere with other air agencies' plans 
to protect visibility.
---------------------------------------------------------------------------

    \118\ Final action approved on February 12, 2018 (83 FR 5927).
    \119\ See 83 FR 62204 (November 30, 2018) for proposed approval 
and 84 FR 51033 (September 27, 2019) for final approval.
---------------------------------------------------------------------------

D. CAA Section 110(l)

    We propose to find that approval of the Arkansas Regional Haze 
Phase III SIP revision and concurrent withdrawal of the corresponding 
parts of the FIP, as proposed, meet the provisions of CAA section 
110(l).

VIII. Incorporation by Reference

    In this action, we propose to include in a final rule regulatory 
text that includes incorporation by reference. In accordance with the 
requirements of 1 CFR 51.5, we propose to incorporate by reference 
revisions to the Arkansas source specific requirements as described in 
the Proposed Action section above. We have made, and will continue to 
make, these documents generally available electronically through 
www.regulations.gov and in hard copy at the EPA Region 6 office (please 
contact James E. Grady, 214-665-6745, grady.james@epa.gov for more 
information).

IX. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the Act and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, the EPA's role is to approve state choices, 
provided that they meet the criteria of the CAA. Accordingly, this 
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 action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993), 13563 (76 FR 3821, January 21, 
2011), and 13771 (82 FR 9339, February 2, 2017);
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     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);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or

[[Page 14869]]

safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 
1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     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; and
     Does not provide the EPA with the discretionary authority 
to address, as appropriate, disproportionate human health or 
environmental effects, using practicable and legally permissible 
methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, the SIP is not approved to apply on any Indian 
reservation land or in any other area where the EPA or an Indian tribe 
has demonstrated that a tribe has jurisdiction. In those areas of 
Indian country, the proposed 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, Best Available 
Retrofit Technology, Carbon monoxide, Incorporation by reference, 
Intergovernmental relations, Lead, Nitrogen dioxide, Ozone, Particulate 
matter, Reporting and recordkeeping requirements, Regional haze, Sulfur 
dioxide, Visibility, Volatile organic compounds.

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

    Dated: March 6, 2020.
Kenley McQueen,
Regional Administrator, Region 6.
[FR Doc. 2020-05106 Filed 3-13-20; 8:45 am]
 BILLING CODE 6560-50-P