Document ID: EPA-R08-OAR-2015-0463-0225
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: Utah; Regional Haze State and Federal Implementation Plans
Posted Date: 2020-01-22T05:00Z

[Federal Register Volume 85, Number 14 (Wednesday, January 22, 2020)]
[Proposed Rules]
[Pages 3558-3578]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-00495]

[[Page 3558]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R08-OAR-2015-0463; FRL-10003-90-Region 8]

Approval and Promulgation of Air Quality Implementation Plans; 
Utah; Regional Haze State and Federal Implementation Plans

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to take 
action pursuant to section 110 of the Clean Air Act (CAA or Act) on 
State Implementation Plan (SIP) revisions submitted by the State of 
Utah on July 3, 2019, as supplemented on December 3, 2019, to satisfy 
certain regional haze requirements for the program's first 
implementation period. The EPA is proposing to approve the July 2019 
SIP revision that provides an alternative to best available retrofit 
technology (BART) controls for nitrogen oxides (NOX) at the 
PacifiCorp Hunter and Huntington power plants. The EPA proposes to find 
that the Utah NOX BART Alternative for Hunter and Huntington 
would provide greater reasonable progress toward natural visibility 
conditions than BART, in accordance with the requirements of the CAA 
and the EPA's Regional Haze Rule (RHR). In conjunction with this 
proposed approval, we propose to withdraw the federal implementation 
plan (FIP) that addresses NOX BART for the Hunter and 
Huntington power plants. The EPA also proposes to approve the December 
3, 2019 SIP supplement that would require reporting of all deviations 
from compliance with the applicable requirements under BART and the 
BART Alternative, including the emission limits for Hunter and 
Huntington.

DATES: 
    Comments: Written comments must be received on or before March 23, 
2020.
    Public Hearing: A public hearing for this proposal is scheduled to 
be held on Wednesday, February 12, 2020, in Price, Utah from 1 p.m. 
until 5 p.m., and again from 6 p.m. until 8 p.m. mountain standard time 
(MST). See the SUPPLEMENTARY INFORMATION section below for the venue 
address.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R08-
OAR-2015-0463, to the Federal Rulemaking Portal: https://www.regulations.gov. Follow the online instructions for submitting 
comments. Once submitted, comments cannot be edited or removed from 
www.regulations.gov. The EPA may publish any comment received to its 
public docket. Do not submit electronically any information you 
consider to be Confidential Business Information (CBI) or other 
information whose disclosure is restricted by statute. Multimedia 
submissions (audio, video, etc.) must be accompanied by a written 
comment. The written comment is considered the official comment and 
should include discussion of all points you wish to make. The EPA will 
generally not consider comments or comment contents located outside of 
the primary submission (i.e., on the web, cloud, or other file sharing 
system). For additional submission methods, the full EPA public comment 
policy, information about CBI or multimedia submissions, and general 
guidance on making effective comments, please visit http://www.epa.gov/dockets/commenting-epa-dockets.
    Docket: All documents in the docket are listed in the 
www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, will be publicly available only in hard copy. 
Publicly available docket materials are available either electronically 
in www.regulations.gov or in hard copy at the Air Program, 
Environmental Protection Agency (EPA), Region 8, 1595 Wynkoop Street, 
Denver, Colorado 80202-1129. The EPA requests that, if at all possible, 
you contact the individual listed in the FOR FURTHER INFORMATION 
CONTACT section to view the hard copy of the docket. You may view the 
hard copy of the docket Monday through Friday, 8:00 a.m. to 4:00 p.m., 
excluding federal holidays.

FOR FURTHER INFORMATION CONTACT: Aaron Worstell, Air Program, EPA, 
Region 8, Mailcode 8P-AR, 1595 Wynkoop Street, Denver, Colorado 80202-
1129, (303) 312-6073, worstell.aaron@epa.gov.

SUPPLEMENTARY INFORMATION:

Public Hearing

    A public hearing will be held at the Jennifer Leavitt Student 
Center (JLSC),\1\ Utah State University Eastern, 400 North 410 East, 
Price, UT 84501, on Wednesday, February 12, 2020. The hearing will 
convene at 1 p.m. and run from 1 p.m. until 5 p.m., and again from 6 
p.m. until 8 p.m. (MST). Persons wishing to preregister may be assigned 
a time according to this schedule. Please register at https://utah-regional-haze-2020.eventbrite.com to speak at the hearing. The last day 
to preregister in advance to speak at the hearing is February 3, 2020. 
Additionally, requests to speak may be taken the day of the hearing at 
the hearing registration desk on a first come first serve basis, as 
time allows. The EPA will make every effort to accommodate all walk-in 
speakers, however we highly encourage the public to preregister for the 
hearing in order to be guaranteed speaking time. For questions 
regarding the public hearing, please contact Clayton Bean at 
bean.clayton@epa.gov or (303) 312-6143.
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    \1\ See https://usueastern.edu/about/map/_documents/PriceCampusMap.pdf for a detailed campus map.
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    The public hearing will provide interested parties the opportunity 
to present data, views, or arguments concerning the proposed action. 
The EPA may ask clarifying questions during the oral presentations, but 
will not respond to the presentations at that time. Written statements 
and supporting information submitted during the comment period will be 
considered with the same weight as oral comments and supporting 
information presented at the public hearing. The hearing officer may 
limit the time available for each commenter to address the proposal to 
5 minutes or less if the hearing officer determines it to be 
appropriate. The limitation is to ensure that everyone who wants to 
make a comment has the opportunity to do so. We will not be providing 
equipment for commenters to show overhead slides or make computerized 
slide presentations. Any person may provide written or oral comments 
and data pertaining to our proposal at the public hearings. Verbatim 
transcripts, in English, of the hearings and written statements will be 
included in the rulemaking docket.
    Throughout this document wherever ``we,'' ``us,'' or ``our'' is 
used, we mean the EPA.

Table of Contents

I. What action is the EPA proposing?
II. Background
    A. Requirements of the Clean Air Act and the EPA's Regional Haze 
Rule
    B. Best Available Retrofit Technology (BART)
    C. BART Alternatives
    D. Requirements for Regional Haze SIPs Submitted Under 40 CFR 
51.309
    E. Monitoring, Recordkeeping and Reporting
    F. Consultation With Federal Land Managers (FLMs)

[[Page 3559]]

    G. Summary of State Regional Haze Submittals and EPA Actions
    1. 2008 and 2011 Utah Regional Haze SIP Submissions
    2. 2012 EPA Action on 2011 and 2008 Utah Regional Haze SIP 
Submissions
    3. Petitions for Review of the EPA's Approval of the 
SO2 Backstop Trading Program
    4. 2015 Utah Regional Haze SIP Submissions
    5. 2016 EPA Action on 2015 Utah RH SIP Submissions
    6. Petitions for Review of EPA's 2016 SIP Disapproval and FIP
    7. 2019 Utah RH SIP Revisions
III. Utah's Regional Haze SIP Revisions
    A. Summary of the Utah NOX BART Alternative SIP 
Revision
    1. Utah NOX BART Alternative
    B. Summary of Utah's Demonstration for Alternative Program
    1. List of All BART-Eligible Sources Within the State
    2. List of All BART-Eligible Sources and All BART Source 
Categories Covered by the Alternative Program
    3. Analysis of BART and Associated Emission Reductions 
Achievable
    4. Analysis of Projected Emissions Reductions Achievable Through 
the BART Alternative
    5. A Determination That the Alternative Achieves Greater 
Reasonable Progress Than Would Be Achieved Through the Installation 
and Operation of BART
    6. Requirement That Emission Reductions Take Place During Period 
of First Long-Term Strategy
    7. Demonstration That Emissions Reductions From Alternative 
Measure Will Be Surplus
    C. Monitoring, Recordkeeping and Reporting
    D. Consultation With FLMs
IV. EPA's Evaluation and Proposed Approval of Utah's Regional Haze 
SIP
    A. Basis for Proposed Approval
    B. Demonstration of Greater Reasonable Progress for the 
Alternative Program
    1. A List of All BART-Eligible Sources Within the State
    2. A List of All BART-Eligible Sources and All BART Source 
Categories Covered by the Alternative Program
    3. Analysis of BART and Associated Emission Reductions
    4. Analysis of Projected Emissions Reductions Achievable Through 
the BART Alternative
    5. A Determination That the Alternative Achieves Greater 
Reasonable Progress Than Would Be Achieved Through the Installation 
and Operation of BART
    6. Requirement That Emission Reductions Take Place During Period 
of First Long-Term Strategy
    7. Demonstration That Emission Reductions From Alternative 
Measure Will Be Surplus
    C. Monitoring, Recordkeeping, and Reporting
    D. Consultation With FLMs
V. Clean Air Act Section 110(l)
VI. The EPA's Proposed Action
    A. 2019 Utah Regional Haze SIP Revision
    B. FIP Withdrawal
    C. Clean Air Section 110(l)
VII. Incorporation by Reference
VIII. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and 
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Executive Order 13771: Reducing Regulations and Controlling 
Regulatory Costs
    C. Paperwork Reduction Act
    D. Regulatory Flexibility Act
    E. Unfunded Mandates Reform Act (UMRA)
    F. Executive Order 13132: Federalism
    G. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    H. Executive Order 13045: Protection of Children From 
Environmental Health Risks and Safety Risks
    I. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use
    J. National Technology Transfer and Advancement Act
    K. Executive Order 12898: Federal Actions To Address 
Environmental Justice in Minority Populations and Low-Income 
Populations

I. What action is the EPA proposing?

    On July 5, 2016, the EPA promulgated a final rule titled 
``Approval, Disapproval and Promulgation of Air Quality Implementation 
Plans; Partial Approval and Partial Disapproval of Air Quality 
Implementation Plans and Federal Implementation Plan; Utah; Revisions 
to Regional Haze State Implementation Plan; Federal Implementation Plan 
for Regional Haze,'' which approved, in part, a regional haze SIP 
revision submitted by the State of Utah on June 4, 2015.\2\ In the July 
2016 final rule, the EPA also disapproved, in part, the Utah regional 
haze SIP submission, including the NOX BART Alternative 
(also ``BART Alternative'' or ``Alternative'') for Hunter Units 1 and 2 
and Huntington Units 1 and 2, which are BART units as explained in more 
detail below. The BART Alternative relied on sulfur dioxide 
(SO2), NOX, and particulate matter (PM) emission 
reductions stemming from the 2015 closure of PacifiCorp's Carbon power 
plant, as well as NOX reductions achieved through combustion 
control upgrades at Hunter Units 1, 2, and 3 and Huntington Units 1 and 
2. (Hunter Unit 3 is not a BART unit.) The combustion control upgrades 
for Hunter Units 1 and 2 and Huntington Units 1 and 2 include an Alstom 
TSF 2000\TM\ low-NOX firing system and two elevations of 
separated overfire air (SOFA). The combustion upgrades for Hunter Unit 
3 include upgraded low-NOX burners (LNB) and overfire air 
(OFA). Concurrent with disapproving the NOX BART 
Alternative, EPA promulgated a FIP in the July 2016 final rule that 
imposed a NOX BART emission limit of 0.07 lb/MMBtu (30-day 
rolling average) for each of the four BART units based on the emission 
reductions achievable through the installation and operation of 
selective-catalytic reduction (SCR) plus upgraded combustion controls.
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    \2\ 81 FR 43894 (July 5, 2016).
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    On July 3, 2019, Utah submitted a revised SIP that, based on new 
technical information and a different regulatory test, seeks to 
demonstrate that the previously submitted NOX BART 
Alternative achieves greater reasonable progress than BART. The SIP 
revision also includes amendments to Utah's SO2 milestone 
reporting requirements under the SO2 Backstop Trading 
Program pursuant to 40 CFR 51.309 so that SO2 emission 
reductions resulting from the closure of the Carbon plant are not 
counted under both the SO2 Backstop Trading Program and the 
NOX BART Alternative. The EPA is proposing to approve the 
State's July 3, 2019 SIP revision based on this new information and to 
incorporate the following into Utah's SIP:
     A NOX emission limit of 0.26 lb/MMBtu (30-day 
rolling average) each for Hunter Units 1 and 2 and Huntington 1 and 2.
     A NOX emission limit of 0.34 lb/MMBtu (30-day 
rolling average) for Hunter Unit 3.
     A requirement to permanently close and cease operation of 
the Carbon power plant by August 15, 2015.
     The associated amendments to the SO2 milestone 
reporting requirements.
    Because approval of the NOX BART Alternative would 
satisfy Utah's BART obligation for Hunter Units 1 and 2 and Huntington 
Units 1 and 2, we are also proposing to withdraw the FIP for 
NOX BART at these units.
    The EPA is also proposing to approve a December 3, 2019 SIP 
supplement to the July 3, 2019 SIP revision that includes monitoring, 
recordkeeping and reporting (MRR) requirements for the units subject to 
the NOX BART Alternative and PM BART. The supplement also 
includes amendments that require each source to submit a report of any 
deviation from applicable emission limits and operating practices, 
including deviations attributable to upset conditions, the probable 
cause of such deviations, and any corrective actions or preventive 
measures taken.
    Finally, contingent on our approval of these two SIP revisions, we 
propose to find that Utah's SIP fully satisfies the

[[Page 3560]]

requirements of section 309 of the RHR and, therefore, that the State 
has fully complied with the requirements for reasonable progress, 
including BART, for the first implementation period.
    EPA is requesting comment on its proposed approval of Utah's 
regional haze SIP elements related to the NOX BART 
Alternative under 40 CFR 51.309(d)(4)(vii) and 51.308(e)(2)-(3), as 
well as the MRR elements for the units subject to that BART Alternative 
and to PM BART. EPA previously approved Utah's regional haze SIP as 
meeting all other requirements of 40 CFR 51.309,\3\ and we are neither 
reopening nor requesting comment on previously approved elements here.
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    \3\ See 77 FR 74355 (Dec. 14, 2012); 81 FR 43894 (July 5, 2016).
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II. Background

A. Requirements of the Clean Air Act and the EPA's Regional Haze Rule

    In section 169A of the 1977 Amendments to the CAA, Congress created 
a program for protecting visibility in the nation's national parks and 
wilderness areas. This section of the CAA establishes ``as a national 
goal the prevention of any future, and the remedying of any existing, 
impairment of visibility in mandatory Class I Federal areas which 
impairment results from manmade air pollution.'' \4\ Section 169A 
directs the EPA to establish regulations for states to submit SIPs to 
make ``reasonable progress'' toward the national visibility goal 
through long-term strategies and to implement BART at certain BART-
eligible sources. Recognizing the complexity of addressing visibility 
impacts, Congress enacted section 169B in the 1990 Amendments to the 
CAA, which, among other things, dedicated greater resources to 
``regional haze'' and the problem of visibility impairment due to 
pollution transport over large distances. Section 169B provided for the 
creation of ``visibility transport'' regions and commissions, and 
specifically directed the establishment of a Grand Canyon visibility 
transport commission at section 169B(f).
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    \4\ 42 U.S.C. 7491(a). Areas designated as mandatory Class I 
Federal areas consist of national parks exceeding 6,000 acres, 
wilderness areas and national memorial parks exceeding 5,000 acres, 
and all international parks that were in existence on August 7, 
1977. 42 U.S.C. 7472(a). In accordance with section 169A of the CAA, 
EPA, in consultation with the Department of Interior, promulgated a 
list of 156 areas where visibility is identified as an important 
value. 44 FR 69122 (November 30, 1979). The extent of a mandatory 
Class I area includes subsequent changes in boundaries, such as park 
expansions. 42 U.S.C. 7472(a). Although states and tribes may 
designate as Class I additional areas whose visibility they consider 
to be an important value, the requirements of the visibility program 
set forth in section 169A of the CAA apply only to ``mandatory Class 
I Federal areas.'' Each mandatory Class I Federal area is the 
responsibility of a ``Federal Land Manager.'' 42 U.S.C. 7602(i). 
When we use the term ``Class I area'' in this section, we mean a 
``mandatory Class I Federal area.'' The list of mandatory Class I 
Federal areas is located in 40 CFR part 81 subpart D.
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    The EPA promulgated a rule to address regional haze on July 1, 
1999.\5\ This RHR revised the existing visibility regulations \6\ to 
integrate provisions addressing regional haze and established a 
comprehensive visibility protection program for Class I areas. The 
requirements for regional haze, found at 40 CFR 51.308 and 40 CFR 
51.309, are included in the EPA's visibility protection regulations at 
40 CFR 51.300 through 40 CFR 51.309. As discussed in more detail below, 
section 309 is available to certain western states, including Utah, in 
lieu of certain requirements in section 308. The EPA revised the RHR 
most recently on January 10, 2017.\7\
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    \5\ 64 FR 35714 (July 1, 1999) (codified at 40 CFR part 51, 
subpart P).
    \6\ The EPA had previously promulgated regulations to address 
visibility impairment in Class I areas that is ``reasonably 
attributable'' to a single source or small group of sources, i.e., 
reasonably attributable visibility impairment (RAVI). 45 FR 80084 
(December 2, 1980).
    \7\ 82 FR 3078 (January 10, 2017).
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    The CAA requires each state to develop a SIP to meet various air 
quality requirements, including protection of visibility.\8\ Regional 
haze SIPs must assure reasonable progress toward the national goal of 
achieving natural visibility conditions in Class I areas, which, for 
the first implementation period, includes satisfying the BART 
requirements. A state must submit its SIP and SIP revisions to the EPA 
for approval. EPA reviews SIP submissions against the requirements of 
the CAA and applicable regulations. If EPA finds that a state has 
failed to make a required submission or that a submission does not 
satisfy the minimum criteria for completeness, or if EPA disapproves a 
SIP submission in whole or in part, EPA is required to promulgate a FIP 
within two years of such finding or disapproval unless the State 
corrects the deficiency, and the Administrator approves the plan or 
plan revision, before the Administrator promulgates such FIP.\9\ Once 
approved, a SIP is enforceable by the EPA and citizens under the CAA; 
that is, the SIP is federally enforceable.
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    \8\ 42 U.S.C. 7410(a), 7491, and 7492(a); CAA sections 110(a), 
169A, and 169B.
    \9\ 42 U.S.C. 7410(c)(1).
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B. Best Available Retrofit Technology (BART)

    Section 169A of the CAA directs states as part of their SIPs, or 
the EPA when developing a FIP in the absence of an approved regional 
haze SIP, to evaluate the use of retrofit controls at certain larger, 
often uncontrolled, older stationary sources in order to address 
visibility impacts from these sources. Specifically, section 
169A(b)(2)(A) of the CAA requires states' implementation plans to 
contain such measures as may be necessary to make reasonable progress 
toward the natural visibility goal, including a requirement that 
certain categories of existing major stationary sources built between 
1962 and 1977 procure, install, and operate the ``Best Available 
Retrofit Technology'' as determined by the states through their SIPs, 
or as determined by the EPA when it promulgates a FIP. Under the RHR, 
states (or the EPA) are directed to conduct BART determinations for 
such ``BART-eligible'' sources that may reasonably be anticipated to 
cause or contribute to any visibility impairment in a Class I area.\10\ 
Sources that are determined to cause or contribute to such impairment 
pursuant to the BART Guidelines are referred to as ``subject-to-BART'' 
sources and must undergo a BART determination applying the five BART 
factors.\11\ Rather than requiring source-specific BART controls, 
states also have the flexibility to adopt an emissions trading program 
or other alternative program for their subject-to-BART sources, so long 
as the alternative provides greater reasonable progress towards 
improving visibility than BART (sometimes referred to as the ``better-
than-BART'' test).\12\
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    \10\ 40 CFR 51.308(e). The EPA designed the Guidelines for BART 
Determinations Under the RHR (Guidelines), 40 CFR part 51, Appendix 
Y, ``to help States and others (1) identify those sources that must 
comply with the BART requirement, and (2) determine the level of 
control technology that represents BART for each source.'' 
Guidelines, Section I.A. Section II of the Guidelines describes the 
four steps to identify BART sources, and Section III explains how to 
identify BART sources (i.e., sources that are ``subject to BART'').
    \11\ CAA section 169A(g)(2); 40 CFR 51.308(e)(1)(ii)(A).
    \12\ 40 CFR 51.308(e)(2); WildEarth Guardians v. EPA, 770 F.3d 
919 (10th Cir. 2014).
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C. BART Alternatives

    States opting to submit an alternative program in lieu of source-
specific BART, whether for a SIP submitted under 40 CFR 51.308 or 
51.309,\13\ must meet requirements under 40 CFR 51.308(e)(2) and, if 
applicable, (e)(3). These requirements for alternative programs relate 
to the ``better-than-BART'' test and fundamental elements of any 
alternative program.
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    \13\ See 40 CFR 51.309(d)(4).
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    In order to demonstrate that the alternative program achieves 
greater reasonable progress than source-specific

[[Page 3561]]

BART, a state, or the EPA if developing a FIP, must demonstrate that 
its SIP meets the requirements, as applicable, in 40 CFR 
51.308(e)(2)(i) through (vi). Among other things, the state or the EPA 
must conduct an analysis of the best system of continuous emission 
control technology available and the associated emission reductions 
achievable for each source subject to BART covered by the alternative 
program, termed a ``BART benchmark.'' Where the alternative program has 
been designed to meet requirements other than BART, simplifying 
assumptions may be used to establish a BART benchmark. The BART 
benchmark is the basis for comparison in the ``better-than-BART'' test 
for BART alternatives.
    Pursuant to 40 CFR 51.308(e)(2)(i)(E), the state or the EPA must 
provide a determination that the alternative program achieves greater 
reasonable progress than BART under 40 CFR 51.308(e)(3) or otherwise 
based on the clear weight of evidence. 40 CFR 51.308(e)(3), in turn, 
provides specific tests applicable under specific circumstances for 
determining whether the alternative achieves greater reasonable 
progress than BART. If the distribution of emissions under the 
alternative program is not substantially different than for BART, and 
the alternative program results in greater emissions reductions of each 
relevant pollutant than BART, then the alternative program may be 
deemed to achieve greater reasonable progress. If the distribution of 
emissions is significantly different, the differences in visibility 
improvement between BART and the alternative program must be determined 
by conducting dispersion modeling for each impacted Class I area for 
the best and worst 20 percent of days. This modeling demonstrates 
``greater reasonable progress'' if both of the two following criteria 
are met: (1) Visibility does not decline in any Class I area; and (2) 
there is overall improvement in visibility when comparing the average 
differences between BART and the alternative program across all the 
affected Class I areas.
    Alternately, pursuant to 40 CFR 51.308(e)(2)(i)(E), a third test is 
available under which States may show that the BART alternative 
achieves greater reasonable progress than BART ``based on the clear 
weight of evidence.'' As stated in in the EPA's revisions to the RHR 
governing alternative to source-specific BART determinations, such 
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. 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 program 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 program as compared to BART sources, 
monitoring data and emissions inventories, and sensitivity analyses 
of any models used. This array of information and other relevant 
data may be of sufficient quality to inform the comparison of 
visibility impacts between BART and the alternative program. In 
showing that an alternative program is better than BART and when 
there is confidence that the difference in visibility impacts 
between BART and the alternative scenarios are expected to be large 
enough, a weight of evidence comparison may be warranted in making 
the comparison. The EPA will carefully consider the evidence before 
us in evaluating any SIPs submitted by States employing such an 
approach.\14\
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    \14\ 71 FR 60612, 60622 (Oct. 13, 2006).

    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. Pursuant to 40 CFR 
51.309(e)(2)(v), states have the option of including a provision that 
the emissions trading program or other alternative measure include a 
geographic enhancement to the program to address the requirement under 
40 CFR 51.302(c) related to BART for RAVI from the pollutants covered 
under the emissions trading program or other alternative measure.
    A SIP or FIP addressing regional haze must include emission limits 
and compliance schedules for each visibility-impairing pollutant 
emitted from each source subject to BART. In addition to the RHR's 
requirements, general SIP requirements mandate that the SIP or FIP 
include all regulatory requirements related to MRR needed to make 
emission limits practically enforceable.\15\
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    \15\ CAA section 110(a); 40 CFR part 51, subpart K; 40 CFR part 
51, appendix V.
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D. Requirements for Regional Haze SIPs Submitted Under 40 CFR 51.309

    EPA's RHR provides two paths to address regional haze for the first 
implementation period of the regional haze program. One is through 40 
CFR 51.308, requiring, among other things, SIPs to include source-
specific BART determinations or BART alternatives, and to contain long-
term strategies that include enforceable emission limitations, 
compliance schedules, and other measures as necessary to achieve 
reasonable progress in Class I areas inside the state and in Class I 
areas outside the state that may be affected by emissions from the 
state. In addition to these requirements, each regional haze SIP or FIP 
under section 308 must contain measures as necessary to make reasonable 
progress towards the national visibility goal.\16\ The other method for 
addressing regional haze for the first implementation period is through 
40 CFR 51.309, which provides an option for nine states termed the 
``Transport Region States'': Arizona, California, Colorado, Idaho, 
Nevada, New Mexico, Oregon, Utah, and Wyoming. Among other things, by 
meeting the requirements under 40 CFR 51.309, these states can be 
deemed to be making reasonable progress toward the national goal of 
achieving natural visibility conditions for the 16 Class I areas on the 
Colorado Plateau.\17\
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    \16\ 40 CFR 51.308(d), (f).
    \17\ 40 CFR 51.309(a).
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    Section 309 requires those Transport Region States that choose to 
participate to adopt regional haze strategies that are based on 
recommendations from the Grand Canyon Visibility Transport Commission 
(GCVTC) established under CAA 169B(f) for protecting the 16 Class I 
areas on the Colorado Plateau. The purpose of the GCVTC was to assess 
information about the adverse impacts on visibility in and around the 
16 Class I areas on the Colorado Plateau and provided policy 
recommendations to the EPA to address such impacts. The GCVTC 
determined that all Transport Region States could potentially impact 
the Class I areas on the Colorado Plateau. The GCVTC submitted a report 
to the EPA in 1996 containing recommendations for protecting visibility 
for the Class I areas on the Colorado Plateau, and the EPA codified 
these recommendations in section 309 as an option available to states 
as part of the RHR.\18\
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    \18\ 64 FR 35714, 35749 (July 1, 1999).
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    The EPA determined that the GCVTC strategies would provide for 
reasonable progress in mitigating regional haze if supplemented by an 
annex containing quantitative emission reduction milestones and 
provisions for a trading program or other alternative measure for 
SO2.\19\ In September 2000, the Western Regional Air 
Partnership (WRAP), which is the successor organization to the GCVTC, 
submitted an annex to EPA.

[[Page 3562]]

The annex contained SO2 emissions reduction milestones and 
detailed provisions of a backstop trading program to be implemented 
automatically if voluntary measures failed to achieve the 
SO2 milestones (the SO2 Backstop Trading 
Program). The EPA codified the annex on June 5, 2003 at 40 CFR 
51.309(h).\20\
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    \19\ 64 FR 35714, 35749, 35756 (July 1, 1999).
    \20\ 68 FR 33764, 33767 (June 5, 2003).
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    Five western states, including Utah, submitted implementation plans 
under section 309 in 2003.\21\ However, the EPA was challenged by the 
Center for Energy and Economic Development (CEED) on the validity of 
the annex provisions contained in section 309(h). In CEED v. EPA, the 
D.C. Circuit Court of Appeals vacated the EPA approval of the WRAP 
annex.\22\ In response to the court's decision, the EPA removed the 
annex requirements from 40 CFR 51.309(h), but incorporated the 
provisions allowing for an SO2 Backstop Trading Program 
under the stationary source requirements in 40 CFR 51.309(d)(4).\23\ 
The requirements under 40 CFR 51.309(d)(4) contain general requirements 
pertaining to stationary sources and market trading, and allow states 
to adopt alternatives to source-specific application of BART.
---------------------------------------------------------------------------

    \21\ Five states--Arizona, New Mexico, Oregon, Utah and 
Wyoming--and Albuquerque-Bernalillo County, New Mexico, initially 
exercised this option by submitting plans to the EPA in December 
2003. Oregon elected to cease participation in 2006, and Arizona 
elected to cease participation in 2010.
    \22\ Ctr. for Energy & Econ. Dev. v. EPA, 398 F.3d 653, 654 (DC 
Cir. 2005).
    \23\ 71 FR 60612 (October 13, 2006).
---------------------------------------------------------------------------

    Under 40 CFR 51.309, states can satisfy the SO2 BART 
requirements by adopting SO2 emissions milestones and the 
SO2 Backstop Trading Program as described in 
51.309(d)(4)(i)-(vi). Under this approach, states must establish 
declining SO2 emissions milestones for each year of the 
program through 2018. The milestones must be consistent with the 
GCVTC's goal of 50 to 70 percent reduction in SO2 emissions 
by 2040. The SO2 Backstop Trading Program would be 
implemented if a milestone is exceeded and the program is 
triggered.\24\
---------------------------------------------------------------------------

    \24\ 40 CFR 51.309(d)(4)(v).
---------------------------------------------------------------------------

    Section 51.309(d)(4) includes not only provisions for stationary 
source emissions of SO2, but also a requirement that 
Transport Region States' implementation plans contain any necessary 
long-term strategies and BART requirements for stationary source PM and 
NOX emissions. Pursuant to 40 CFR 51.309(d)(4)(vii), any 
BART provisions may be submitted pursuant to either 51.308(e)(1) or 
51.308(e)(2); that is, states may submit either source-specific BART 
determinations or BART alternatives for PM and NOX.

E. Monitoring, Recordkeeping and Reporting

    The CAA requires that SIPs, including regional haze SIPs, contain 
elements sufficient to ensure emission limits are practically 
enforceable. CAA section 110(a)(2) states that the MRR provisions of 
states' SIPs must:

    (A) include enforceable emission limitations and other control 
measures, means, or techniques (including economic incentives such 
as fees, marketable permits, and auctions of emissions rights), as 
well as schedules and timetables for compliance, as may be necessary 
or appropriate to meet the applicable requirements of this chapter; 
. . . (C) include a program to provide for the enforcement of the 
measures described in subparagraph (A), and regulation of the 
modification and construction of any stationary source within the 
areas covered by the plan as necessary to assure that national 
ambient air quality standards are achieved, including a permit 
program as required in parts C and D of this subchapter; . . . (F) 
require, as may be prescribed by the Administrator--(i) the 
installation, maintenance, and replacement of equipment, and the 
implementation of other necessary steps, by owners or operators of 
stationary sources to monitor emissions from such sources, (ii) 
periodic reports on the nature and amounts of emissions and 
emissions-related data from such sources, and (iii) correlation of 
such reports by the State agency with any emission limitations or 
standards established pursuant to this chapter, which reports shall 
be available at reasonable times for public inspection.

    Accordingly, 40 CFR part 51, subpart K, Source Surveillance, 
requires the SIP to provide for monitoring the status of compliance 
with the regulations in it, including ``[p]eriodic testing and 
inspection of stationary sources,'' \25\ and ``legally enforceable 
procedures'' for recordkeeping and reporting.\26\ Furthermore, 40 CFR 
part 51, appendix V, Criteria for Determining the Completeness of Plan 
Submissions, states in section 2.2 that complete SIPs contain: ``(g) 
Evidence that the plan contains emission limitations, work practice 
standards and recordkeeping/reporting requirements, where necessary, to 
ensure emission levels''; and ``(h) Compliance/enforcement strategies, 
including how compliance will be determined in practice.''
---------------------------------------------------------------------------

    \25\ 40 CFR 51.212(a).
    \26\ 40 CFR 51.211.
---------------------------------------------------------------------------

F. Consultation With Federal Land Managers (FLMs)

    The statute and the RHR require that a state, or the EPA if 
promulgating a FIP that fills a gap in the SIP with respect to the 
applicable requirements, consult with FLMs before adopting and 
submitting a required SIP or SIP revision, or a required FIP or FIP 
revision.\27\ Further, the state when considering a SIP revision (or 
EPA in a FIP) must include in its proposal a description of how it 
addressed any comments provided by the FLMs.
---------------------------------------------------------------------------

    \27\ CAA section 169A(d); 40 CFR 51.308(i).
---------------------------------------------------------------------------

G. Summary of State Regional Haze Submittals and EPA Actions

1. 2008 and 2011 Utah Regional Haze SIP Submissions
    On May 26, 2011, the State of Utah submitted to EPA a regional haze 
SIP under 40 CFR 51.309 (``2011 Utah RH SIP''). Consistent with 40 CFR 
51.309(d)(4)(vii), this submittal included BART determinations for 
NOX and PM at Utah's four subject-to-BART sources: 
PacifiCorp's Hunter Units 1 and 2 and Huntington Units 1 and 2. All 
four units are tangentially-fired fossil-fuel electric generating units 
(EGUs), each with a net generating capacity of 430 MW, permitted to 
burn bituminous coal. This submittal also included quantitative 
emissions milestones through 2018 and a backstop trading program for 
SO2 intended to meet the requirements of 40 CFR 
51.309(d)(4)(i)-(vi). The SO2 backstop trading program 
covers Utah, Wyoming, New Mexico and the City of Albuquerque.
    Utah had also previously submitted SIPs on December 12, 2003, 
August 8, 2004, and September 9, 2008, to meet the requirements of the 
RHR. These submittals were, for the most part, superseded and replaced 
by the May 26, 2011 submittal as further explained in the next section.
2. 2012 EPA Action on 2011 and 2008 Utah Regional Haze SIP Submissions
    On December 14, 2012, EPA partially approved and partially 
disapproved the 2011 Utah RH SIP.\28\ We approved the 2011 Utah RH SIP 
as meeting the requirements of 40 CFR 51.309, with the exception of the 
requirements under 40 CFR 51.309(d)(4)(vii) pertaining to 
NOX and PM BART. EPA's partial disapproval action was based 
on the following: (1) Utah did not take into account the five statutory 
factors in its BART analyses for NOX and PM; and (2) the 
2011 Utah RH SIP submission did not contain the provisions necessary to 
make the BART limits practically enforceable as required by section 
110(a)(2) of the CAA and 40 CFR 51, appendix V.\29\
---------------------------------------------------------------------------

    \28\ 77 FR 74355, 74357 (Dec. 14, 2012).
    \29\ Id.

---------------------------------------------------------------------------

[[Page 3563]]

    We also approved two sections of the 2008 Utah RH SIP submission in 
the December 13, 2012 action. Specifically, we approved state rules UAR 
R307-250--Western Backstop Sulfur Dioxide Trading Program and R307-
150--Emission Inventories. We took no action on the rest of the 2008 
submittal as the 2011 submittal superseded and replaced all other 
sections. We also took no action on the December 12, 2003 and August 8, 
2004 submittals as these were superseded by the 2011 submittal.
    On November 8, 2011, we separately proposed approval of Section G--
Long-Term Strategy for Fire Programs of the May 26, 2011 submittal and 
finalized our approval of that action on January 18, 2013.\30\
---------------------------------------------------------------------------

    \30\ 78 FR 4071, 4072 (Jan. 18, 2013).
---------------------------------------------------------------------------

3. Petitions for Review of the EPA's Approval of the SO2 
Backstop Trading Program
    In 2013, conservation organizations challenged EPA's 2012 approval 
of the SO2 Backstop Trading Program as an alternative to 
BART for certain Transport Region States, including Utah, in the U.S. 
Court of Appeals for the Tenth Circuit. On October 21, 2014, the Tenth 
Circuit upheld EPA's action, including EPA's finding that the trading 
program could serve as a BART alternative under a ``clear weight of 
evidence'' standard.\31\
---------------------------------------------------------------------------

    \31\ WildEarth Guardians v. United States EPA, 770 F.3d 919, 938 
(10th Cir. 2014).
---------------------------------------------------------------------------

4. 2015 Utah Regional Haze SIP Submissions
    On June 4, 2015, the State of Utah submitted to EPA a revision to 
its Regional Haze SIP under 40 CFR 51.309 of the RHR (``June 2015 Utah 
RH SIP'') to address the requirements under 40 CFR 51.309(d)(4)(vii) 
pertaining to NOX and PM BART. Utah developed the June 2015 
Utah RH SIP in response to EPA's December 14, 2012 partial disapproval 
of the 2011 Utah RH SIP submission. The June 2015 Utah RH SIP evolved 
from a draft SIP on which Utah sought public comment in October 2014. 
After receiving extensive public comments on that draft, Utah decided 
to pursue a NOX BART Alternative under the 40 CFR 
51.308(e)(2) ``clear weight of evidence'' standard that takes credit 
for NOX reductions due to combustion controls installed at 
PacifiCorp's Hunter and Huntington power plants in addition to 
NOX, SO2, and PM reductions from the August 2015 
retirement of PacifiCorp's nearby Carbon power plant. The June 2015 
Utah RH SIP submission also included measures to make the SIP 
requirements practically enforceable and included additional 
information pertaining to the PM BART determinations for Hunter and 
Huntington to address deficiencies identified by EPA in our December 
2012 partial disapproval.
    On October 20, 2015, Utah submitted to EPA another revision to its 
Regional Haze SIP under 40 CFR 51.309 (``October 2015 Utah RH SIP''). 
This SIP included an enforceable commitment to provide an additional 
SIP revision by mid-March 2018 to address concerns raised in public 
comments that the State would be double counting certain SO2 
emissions reductions under both the Utah NOX BART 
Alternative and the milestone reporting for the SO2 Backstop 
Trading Program.
5. 2016 EPA Action on 2015 Utah RH SIP Submissions
    On July 5, 2016, we partially approved and partially disapproved 
the revisions to the Utah SIP submitted by the State of Utah on June 4, 
2015.\32\ We approved the following elements of the State's SIP 
submittals: \33\
---------------------------------------------------------------------------

    \32\ 81 FR 43894 (July 5, 2016).
    \33\ EPA had already approved elements satisfying other 
applicable requirements in the December 14, 2012 action: Section 
XX.B.8, Figures 1 and 2, Affected Class I Areas, pp. 8-9; Section 
XX.D.6.b, Table 3, BART-Eligible Sources in Utah, p. 21; Section 
XX.D.6.c, Sources Subject to BART, pp. 21-23.
---------------------------------------------------------------------------

     BART determinations and emission limits for PM at Hunter 
Units 1 and 2 and Huntington Units 1 and 2.
     MRR requirements for units subject to the PM emission 
limits, including conditional approval of the requirement that the PM 
emission limits apply at all times, subject to the state's commitment 
to adopt reporting requirements for deviations from the emission 
limits.
    We disapproved these aspects of the State's June 4, 2015 SIP:
     NOX BART Alternative, including emission limits 
consistent with upgraded combustion controls at Hunter Units 1, 2, and 
3 and Huntington Units 1 and 2, and the SO2, NOx, and PM 
emission reductions resulting from the shutdown of Carbon Units 1 and 
2.
     MRR requirements for units subject to the NOX 
BART Alternative.
    As noted above, in June 2015 Utah submitted the NOX BART 
Alternative under 40 CFR 51.308(e)(2)(i)(E)'s clear-weight-of-evidence 
test. To support its conclusion that the NOX BART 
Alternative makes greater reasonable progress towards the national 
visibility goal, the SIP submission relied on nine metrics for 
comparing the Alternative to the BART Benchmark: Aggregate emission 
reductions, monitoring data, timing of emission reductions, energy and 
non-air quality impacts, cost, and four visibility-related metrics 
based on the results of a modeling exercise using the CALPUFF model. In 
the July 2016 final rule, EPA determined that the evidence provided did 
not clearly demonstrate that the BART Alternative achieves greater 
visibility improvement than BART. As part of this evaluation, we 
determined which metrics were relevant to the assessment of relative 
visibility benefit, evaluated the strengths and weaknesses of each 
metric in order to determine which merited more or less weight, and 
collectively considered the weights assigned to the individual pieces 
of information in determining whether, on balance, the evidence 
demonstrated that the NOX BART Alternative would clearly 
provide for greater reasonable progress.\34\ Based on this assessment, 
we determined that the evidence before us did not satisfy the standard 
articulated under 40 CFR 51.308(e)(2)(i)(E) and disapproved the 
NOX BART Alternative.
---------------------------------------------------------------------------

    \34\ See 81 FR 43894, 43896-43902.
---------------------------------------------------------------------------

    We thus promulgated a FIP in the July 5, 2016 action to address the 
deficiencies in the Utah regional haze SIP submissions. EPA's FIP 
includes the following elements:
     NOX BART determinations and corresponding 
emission limits for Hunter Units 1 and 2 and Huntington Units 1 and 2 
of 0.07 lb/MMbtu (30-day rolling average) each, reflecting installation 
and operation of SCR plus the existing upgraded combustion controls.
     Monitoring, recordkeeping, and reporting requirements 
applicable to Hunter Units 1 and 2 and Huntington Units 1 and 2 as 
needed to implement the NOX BART determinations and emission 
limits.
    We took no action on the enforceable commitment to revise, at a 
minimum, SIP Section XX.D.3.c and state rule R307-150 addressing double 
counting of SO2 emissions, because there was no need to do 
so once the NOX BART Alternative had been disapproved.
6. Petitions for Review of EPA's 2016 SIP Disapproval and FIP
    In September 2016, the State of Utah, PacifiCorp, and several other 
parties challenged EPA's July 5, 2016 disapproval of the NOX 
BART Alternative and promulgation of a FIP in the U.S. Court of Appeals 
for the Tenth Circuit.\35\ In addition, the State and PacifiCorp (on 
behalf of the co-owners of Hunter Units 1 and 2 and Huntington Units 1 
and 2) submitted letters to EPA on June 30, 2017, identifying new

[[Page 3564]]

information that was not available at the time of EPA's action on 
Utah's 2015 SIP submission, providing additional explanation of 
existing information, and stating an intent to develop and submit to 
EPA additional technical analyses in support of the NOX BART 
Alternative.\36\ On July 14, 2017, the EPA Administrator sent letters 
to the State of Utah and PacifiCorp announcing the Agency's intent to 
reconsider its disapproval of the NOX BART Alternative.\37\ 
On this basis, EPA asked the Tenth Circuit to put the litigation in 
abeyance; on September 11, 2017, the court both granted EPA's request 
to abate the litigation and issued a stay of EPA's July 5, 2016 final 
rule.\38\
---------------------------------------------------------------------------

    \35\ State of Utah v. EPA, No. 16-9541 (10th Cir.).
    \36\ See docket IDs EPA-R08-OAR-2015-0463-0216 (letter from 
State of Utah) and EPA-R08-OAR-2015-0463-0221 (letter from 
PacifiCorp).
    \37\ See docket IDs EPA-R08-OAR-2015-0463-0222 (letter to State 
of Utah) and EPA-R08-OAR-2015-0463-0223 (letter to PacifiCorp).
    \38\ State of Utah v. EPA, No. 16-9541 (10th Cir.), Doc. No. 
10496767.
---------------------------------------------------------------------------

7. 2019 Utah RH SIP Revisions
    On July 3, 2019, Utah submitted a SIP revision intended to replace 
EPA's 2016 FIP provisions for NOX BART. The measures in the 
NOX BART Alternative submitted in July 2019 are identical to 
those in the Alternative submitted in June 2015 (i.e., Utah submitted 
the same NOX BART Alternative in the June 2015 and July 2019 
SIPs). However, while the State had previously relied on the clear-
weight-of-evidence test under 40 CFR 51.308(e)(2)(i)(E) to demonstrate 
that the Alternative achieves greater reasonable progress than BART in 
the June 2015 submission,\39\ the July 2019 submission relies solely on 
the application of the two-prong test under 51.308(e)(3) using 
photochemical grid modeling. Background on these two approaches to 
demonstrating greater reasonable progress is provided in section II.C. 
above.
---------------------------------------------------------------------------

    \39\ For a summary of the weight-of-evidence contained in Utah's 
June 2015 SIP, and EPA's evaluation thereof, refer to the July 2016 
final rule at 81 FR 43897-43902.
---------------------------------------------------------------------------

    The July 3, 2019 SIP submittal includes the emission limitations 
and control measures associated with the NOX BART 
Alternative. It also includes the monitoring, recordkeeping, and 
reporting requirements that EPA previously approved for PM BART, but 
disapproved as applied to the emission limitations and control measures 
associated with the NOX BART Alternative.
    On December 3, 2019, Utah submitted a supplement to the July 2019 
SIP submission that includes an amendment to the monitoring, record 
keeping, and reporting requirements submitted on July 3, 2019. 
Specifically, the amendments require each source to submit a report of 
any deviation from applicable emission limits and operating practices, 
including deviations attributable to upset conditions, the probable 
cause of such deviations, and any corrective actions or preventive 
measures taken.
    This proposed action pertains to the July 3, 2019 SIP submittal as 
supplemented on December 3, 2019.
    Sections 110(a)(2) and 110(l) of the CAA and 40 CFR 51.102 and 
appendix V to part 51 require that a state provide reasonable notice 
and public hearing before adopting a SIP revision and submitting it to 
EPA. Utah, after providing notice, accepted comments on the July 2019 
Utah RH SIP submission from April 1, 2019 through May 15, 2019. 
Similarly, Utah accepted comments on the December 3, 2019 RH SIP 
supplement from October 1, 2019 to October 31, 2019.

III. Utah's Regional Haze SIP Revisions

A. Summary of the Utah NOX BART Alternative SIP Revision

    As noted elsewhere, the EPA previously approved Utah's SIP elements 
satisfying the requirements of 40 CFR 51.309 to address the State's 
regional haze obligations for the first implementation period, other 
than emission limitations corresponding to NOX BART or an 
alternative to BART for NOX and the associated MRR 
requirements, and certain requirements for MRR related to PM BART.\40\ 
Therefore, in this action we are addressing only these outstanding 
elements and certain ancillary SIP revisions necessary to effectuate 
them.
---------------------------------------------------------------------------

    \40\ EPA conditionally approved Utah's MRR requirements for the 
PM BART emission limitations under CAA section 110(k)(4). 81 FR at 
43921.
---------------------------------------------------------------------------

    Utah's July 3, 2019 SIP RH submittal, as supplemented on December 
3, 2019, includes changes to the following provisions, on which we are 
proposing to take action:
     Revised SIP Section XX, Regional Haze, Parts A, Executive 
Summary, and D, Long-Term Strategy for Stationary Sources (revised SIP 
narrative sections including the BART Assessment for NOX); adopted by 
the Utah Air Quality Board on June 24, 2019.
     Revised R307-110-28, General Requirements: State 
Implementation Plan, Regional Haze (state rule that incorporates by 
reference most recently amended SIP Section XX); effective August 15, 
2019.
     SIP Section IX.H.21 General Requirements: Control Measures 
for Area and Point Sources, Emission Limits and Operating Practices, 
Regional Haze Requirements (SIP section laying out MRR requirements for 
control measures); adopted by the Utah Air Quality Board on November 
20, 2019.
     SIP Section IX.H.22 Source Specific Emission Limitations: 
Regional Haze Requirements, Best Available Retrofit Technology (SIP 
section containing emission limitations necessary for NOX 
BART Alternative); adopted by the Utah Air Quality Board on November 
20, 2019.
     Revised R307-110-17, General Requirements: State 
Implementation Plan. Section IX, Control Measures for Area and Point 
Sources, Part H, Emissions Limits (state rule that incorporates by 
reference most recently amended SIP Section IX, Part H); effective on 
November 25, 2019.
     Revised R307-150-3, Emission Inventories, Applicability 
(state rule that addresses reporting of SO2 emissions for 
Carbon power plant under the Western Backstop SO2 Trading 
Program); effective June 25, 2018.
    These six provisions are related to the following two outstanding 
requirements for the first implementation period: NOX BART 
for Hunter Units 1 and 2 and Huntington Units 1 and 2; and MRR 
requirements for the Utah NOX BART Alternative and PM BART 
emission limits to make the SIP requirements practically enforceable.
1. Utah NOX BART Alternative
    To satisfy the requirement of 40 CFR 51.309(d)(4)(vii), Utah has 
opted to establish an alternative to BART for NOX under 40 
CFR 51.308(e)(2). The State's NOX BART Alternative consists 
of upgraded combustion controls on all four subject-to-BART units, 
upgraded combustion controls on Hunter Unit 3, and the shutdown of 
Carbon Units 1 and 2. The emission limits in the July 3, 2019 Utah RH 
SIP submittal, as supplemented on December 3, 2019, are provided in 
Table 1. We further explain the components of the SIP submissions 
below.

[[Page 3565]]

                Table 1--Emission Limits and Shutdown in the Utah BART Alternative and PM SIP \1\
----------------------------------------------------------------------------------------------------------------
                                                 PM limit 2 3  (lb/     NOX limit 4  (lb/
            Source                   Unit         MMBtu, three-run        MMBtu, 30-day           SO2 limit
                                                    test average)       rolling average)
----------------------------------------------------------------------------------------------------------------
Hunter.......................               1   0.015...............  0.26................  NA.
                                            2   0.015...............  0.26................  NA.
                                            3   NA..................  0.34................  NA.
Huntington...................               1   0.015...............  0.26................  NA.
                                            2   0.015...............  0.26................  NA.
Carbon.......................               1   Shutdown by August    Shutdown by August    Shutdown by August
                                                 15, 2015.             15, 2015.             15, 2015.
                                            2   Shutdown by August    Shutdown by August    Shutdown by August
                                                 15, 2015.             15, 2015.             15, 2015.
----------------------------------------------------------------------------------------------------------------
\1\ Obtained from the July 2019 Utah RH SIP, Section IX.H.22.
\2\ Based on annual stack testing.
\3\ The BART PM emission limits were previously approved by in our July 2016 final rule. 81 FR 43894 (July 5,
  2016).
\4\ Based on continuous emission monitoring system (CEMS) measurement.

    The State compared the NOX BART Alternative against a 
BART Benchmark that consists of SCR plus upgraded combustion controls 
on all four BART units. The State noted SCR plus upgraded combustion 
controls would require careful consideration through a source-specific 
five-factor analysis before determining it is BART for these units. 
However, the State used those controls as a stringent benchmark for 
comparison with the NOX BART Alternative. The State remarked 
that its use of SCR plus upgraded combustion controls as a benchmark is 
not a determination that this technology is BART; it is merely a 
conservative approach to evaluating the effectiveness of the 
alternative program. The Utah NOX BART Alternative is 
generally described in SIP Section XX.D.6 with a detailed demonstration 
included in the Staff Review to support the State's assertion that the 
Alternative achieves greater reasonable progress than BART.
    In addition to combustion controls at the Hunter and Huntington 
units, the State intends to rely on the emission reductions resulting 
from the shutdown of a coal-fired power plant. Utah indicated that 
PacifiCorp shut down the Carbon Power Plant in 2015, due to the high 
cost to control mercury to meet the requirements of EPA's Mercury and 
Air Toxics Standards (MATS).\41\ The State noted that the MATS rule was 
finalized in 2011, and the Utah RH SIP contains the requirement for the 
Carbon Power Plant to shut down in August 2015. The emission reductions 
occur after the 2002 base year for Utah's RH SIP and thus, Utah 
asserts, the reductions may be considered as part of an alternative 
strategy under 40 CFR 51.308(e)(2)(iv).
---------------------------------------------------------------------------

    \41\ Utah Regional Haze State Implementation Plan, Staff Review 
of Recommended Alternative to BART for NOX, May 28, 2019, 
p. 24.
---------------------------------------------------------------------------

    The State's demonstration is described in more detail in section 
III.B below. The State's estimates of emissions for the Utah 
NOX BART Alternative and the BART Benchmark are provided in 
Table 2 of section III.B.4 below. EPA developed a summary of the 
emissions reductions based on Utah's emission estimates and this is 
presented in Table 3 of section III.B.4 below.

B. Summary of Utah's Demonstration for Alternative Program

    As discussed above in Section II, a state may opt to implement an 
alternative measure rather than to require sources subject to BART to 
install, operate, and maintain source-specific BART. BART alternatives 
such as the Utah NOX BART Alternative that are not emissions 
trading programs must meet the requirements of 40 CFR 51.308(e)(2)(i)-
(iv).\42\ Utah has included the following information in its July 2019 
SIP revision to address the regulatory criteria for an alternative 
program: \43\
---------------------------------------------------------------------------

    \42\ States may address 40 CFR 51.308(e)(2)(v) at their option.
    \43\ See Staff Review.
---------------------------------------------------------------------------

1. List of 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. Utah included a list of 
BART-eligible sources and noted the following sources are all covered 
by the alternative program:

 PacifiCorp Hunter, Unit 1
 PacifiCorp Hunter, Unit 2
 PacifiCorp, Huntington, Unit 1
 PacifiCorp, Huntington, Unit 2
2. List of All BART-Eligible Sources and All BART 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 EPA as meeting BART, or be otherwise 
addressed under paragraphs 51.308(e)(1) or (e)(4). In this instance, 
the alternative program covers all the BART-eligible sources in the 
state--Hunter Units 1 and 2 and Huntington Units 1 and 2--in addition 
to three non-BART units--PacifiCorp's Hunter Unit 3 and Carbon Units 1 
and 2.
3. Analysis of BART and Associated Emission Reductions Achievable
    Pursuant to 40 CFR 51.308(e)(2)(i)(C), the SIP must include an 
analysis of BART and associated emission reductions achievable at the 
subject-to-BART units covered by the alternative program, here Hunter 
Units 1 and 2 and Huntington Units 1 and 2. In the July 2019 Utah RH 
SIP, the State compared the Utah NOX BART Alternative to the 
most stringent NOX controls, SCR plus upgraded combustion 
controls, at the four BART units, referred to here as the BART 
Benchmark. This is consistent with the BART determination made by EPA 
in our July 2016 final rule.\44\
---------------------------------------------------------------------------

    \44\ In the July 2016 FIP, EPA determined these same controls--
SCR plus LNB/SOFA--constitute BART for each of the four subject-to-
BART units. Utah's July 2019 SIP submittal thus refers to the BART 
Benchmark controls as the ``EPA FIP''; while the controls 
represented by the BART Benchmark and EPA's FIP are indeed the same, 
the relevant comparison for the purpose of this analysis is between 
the BART Benchmark and the BART alternative.
---------------------------------------------------------------------------

4. Analysis of Projected Emissions Reductions Achievable Through the 
BART Alternative
    Pursuant to 40 CFR 51. 308(e)(2)(i)(D), the SIP must include ``[a]n 
analysis of the projected emissions reductions achievable through the . 
. . alternative measure.'' A summary of the State's estimates of 
emissions in tons per year (tpy) for the Baseline, NOX BART 
Alternative and the BART Benchmark is provided in Table 2. A summary of 
the emissions reductions based on those emission estimates is presented 
in Table 3. The emissions and emission reductions were projected for 
the year

[[Page 3566]]

2025 to align with the future year modeling scenarios used to calculate 
visibility benefits under the BART Benchmark and BART Alternative, as 
described in the section that follows.\45\
---------------------------------------------------------------------------

    \45\ Staff Review, Table 2, p. 12. Values rounded to the nearest 
ton.

                                Table 2--Estimated Emissions in 2025 Under the Baseline Scenario, BART Benchmark (BART Benchmark), and the BART Alternative \45\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         NOX (tpy)                                        SO2 (tpy)                            PM (tpy)                         Combined
                                           -------------------------------------            -------------------------------------------------------------------------------------------------------
                   Units                                   BART                                              BART                                BART                                BART     BART
                                             Baseline    benchmark   BART alt.                Baseline    benchmark    BART alt.   Baseline    benchmark   BART alt.   Baseline    benchmark  alt.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ------
Carbon 1..................................       1,312       1,312           0        2,286       2,286           0          120         120           0       3,718       3,718           0
Carbon 2..................................       1,977       1,977           0        3,528       3,528           0          183         183           0       5,688       5,688           0
Hunter 1..................................       6,380         796       3,166        2,535       1,153       1,153          733         733         733       9,648       2,682       5,052
Hunter 2..................................       6,092         798       3,028        2,531       1,408       1,408          717         717         717       9,340       2,923       5,153
Hunter 3..................................       6,530       6,530       4,490        1,204       1,230       1,230          531         531         531       8,265       8,291       6,251
Huntington 1..............................       5,944         793       3,147        2,380       1,254       1,254          517         517         517       8,841       2,564       4,918
Huntington 2..............................       5,816         753       3,366       12,308       1,201       1,201        1,033       1,033       1,033      19,157       2,987       5,600
                                           -----------------------------------------------------------------------------------------------------------------------------------------------------
    Total.................................      34,051      12,959      17,197       26,772      12,060       6,246        3,834       3,834       3,531      64,657      28,853      26,974
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

   Table 3--EPA Summary of 2025 Projected Emission Reductions Achievable With the Utah NOX BART Alternative as
                                         Compared to the BART Benchmark
----------------------------------------------------------------------------------------------------------------
                                                              Combined emissions for all units (tpy)
                   Description                   ---------------------------------------------------------------
                                                        NOX             SO2             PM           Combined
----------------------------------------------------------------------------------------------------------------
BART Benchmark..................................          12,959          12,060           3,834          28,853
BART Alternative................................          17,197           6,246           3,531          26,974
Emission Reduction (BART Benchmark Minus BART             -4,238           5,814             303           1,879
 Alternative) \1\...............................
----------------------------------------------------------------------------------------------------------------
\1\ A negative value indicates the BART Alternative results in more emissions of the specified pollutant in
  comparison to the BART Benchmark.

5. A Determination That the Alternative Achieves Greater Reasonable 
Progress Than Would Be Achieved Through the Installation and Operation 
of BART
    Pursuant to 40 CFR 51.308(e)(2)(i)(E), the State must provide a 
determination that the alternative program achieves greater reasonable 
progress than BART under 40 CFR 51.308(e)(3) or otherwise based on the 
clear weight of evidence.
    Utah noted that the Hunter, Huntington, and Carbon plants are all 
located within 40 miles of each other in central Utah. Because of the 
close proximity of the three plants, the geographic distribution of 
emissions will not be substantially different under the alternative 
program. The combined emissions of NOX, SO2, and 
PM are 1,879 tons/yr lower under the alternative measure. However, the 
NOX BART Alternative measure does not result in greater 
emission reductions of all pollutants--SO2 emissions are 
lower by 5,814 tons/yr, PM are lower by 303 tons/yr, but NOX 
emissions are higher by 4,238 tons/yr. Therefore, because the 
NOX BART Alternative relies on SO2 reductions, 
and to a lesser extent PM reductions, in lieu of NOX 
reductions, Utah determined that greater reasonable progress must be 
demonstrated through the two-prong test based on dispersion modeling in 
40 CFR 51.308(e)(3) or a clear weight of evidence analysis. The State 
chose to make this demonstration in the July 3, 2019 submittal using 
the two-prong test allowed for under 40 CFR 51.308(e)(3). To evaluate 
the two prongs, Utah relied on air quality modeling performed by a 
contractor for PacifiCorp using the Comprehensive Air Quality Model 
with Extensions (CAMx).\46\
---------------------------------------------------------------------------

    \46\ CAMx modeling software and User's Guide are available at 
http://www.camx.com/download/default.aspx. CAMx version 6.10 was 
used for April to December, and CAMx version 6.40 was used for 
January to March.
---------------------------------------------------------------------------

    The CAMx model is a photochemical grid model that uses and produces 
complex scientific data, including emissions from all sources, with a 
realistic representation of formation, transport, and processes that 
cause visibility degradation, estimating downwind concentrations paired 
in space and time. The EPA's guidance supports use of this particular 
model for evaluation of visibility impacts from sources or source 
categories, such as application of the two-prong test under 40 CFR 
51.308(e)(3).\47\ The CAMx model simulates air quality over many 
geographic scales and treats a wide variety of inert and chemically 
active pollutants, including ozone, PM, inorganic and organic 
PM2.5/PM10, and mercury and other toxics. CAMx 
also has plume-in-grid and source apportionment capabilities.\48\ CAMx 
has a scientifically current treatment of chemistry to simulate 
transformation of emissions into visibility-impairing particles of 
species such as ammonium nitrate and ammonium sulfate, and is often 
employed in large-scale modeling when many sources of pollution and/or 
long transport distances are involved. Photochemical grid models like 
CAMx

[[Page 3567]]

include all emissions sources and have realistic representation of 
formation, transport, and removal processes of the particulate matter 
that causes visibility degradation. The use of the CAMx model for 
analyzing potential cumulative air quality impacts has been well 
established: The model has been used for previous visibility modeling 
studies in the U.S., including SIPs.\49\ The modeling followed a 
modeling protocol that was reviewed by the EPA.\50\
---------------------------------------------------------------------------

    \47\ Modeling Guidance for Demonstrating Attainment of Air 
Quality Goals for Ozone, PM2.5, and Regional Haze, EPA 
Office of Air Quality Planning and Standards, Research Triangle 
Park, NC (November 2018). The main regional haze section of the 
guidance is related to setting reasonable progress goals. However, 
the guidance methods may also be applicable to other regional haze 
related modeling, including, but not limited to, evaluation of 
visibility impacts from sources and/or source sectors. See id. at 
143-145. https://www3.epa.gov/ttn/scram/guidance/guide/O3-PM-RH-Modeling_Guidance-2018.pdf. 40 CFR pt. 51, app. Y: IV.D.5 (how to 
determine visibility impacts from the BART determination); 40 CFR 
51.308(e)(3) (use of dispersion modeling for BART alternatives).
    \48\ Photochemical Air Quality Modeling (https://www.epa.gov/scram/photochemical-air-quality-modeling). CAMx is a photochemical 
grid model, which the EPA describes as follows: Photochemical air 
quality models have become widely recognized and routinely utilized 
tools for regulatory analysis and attainment demonstrations by 
assessing the effectiveness of control strategies. These 
photochemical models are large-scale air quality models that 
simulate the changes of pollutant concentrations in the atmosphere 
using a set of mathematical equations characterizing the chemical 
and physical processes in the atmosphere. These models are applied 
at multiple spatial scales, including from local, regional, national 
and global.
    \49\ See, e.g., 84 FR 22711 (May 20, 2019) (Final action for the 
Laramie River Station in the Regional Haze Plan for Wyoming); 82 FR 
46903 (October 10, 2017) (Final action for the Coronado Generating 
Station in the Regional Haze Plan for Arizona); 81 FR 296 (January 
5, 2016) (Final action for Texas and Oklahoma Regional Haze Plans).
    \50\ Photochemical Modeling Protocol to Assess Visibility 
Impacts for PacifiCorp Power Plants Located in Utah. AECOM 
Environment, January 2018.
---------------------------------------------------------------------------

    The Western Air Quality Study (WAQS) \51\ developed and evaluated a 
photochemical modeling platform for calendar year 2011 \52\ for use in 
air quality planning studies in the western U.S. The modeling data 
sets, called the ``WAQS 2011b platform,'' are available to the public 
and served as the starting point for the CAMx modeling exercise. The 
WAQS 2011b modeling included a 2025 future year scenario that was used 
here to assess visibility impacts from the Baseline, BART Benchmark, 
and NOX BART Alternative emissions scenarios.
---------------------------------------------------------------------------

    \51\ Memorandum: Recommendations on Use of Intermountain West 
Data Warehouse for Air Quality 2011b Model Platform. Intermountain 
West Data Warehouse--Western Air Quality Study Oversight Committee. 
July 6, 2016. Available http://views.cira.colostate.edu/wiki/Attachments/Modeling/IWDW-WAQS_2011b_ModelingPlatform_Release_Memo%20July6_2016final.pdf.
    \52\ ``Western Air Quality Modeling Study Photochemical Grid 
Model Final Model Performance Evaluation'', available in the docket 
and at: http://views.cira.colostate.edu/wiki/Attachments/Modeling/WAQS_Base11b_MPE_Final.pdf.
---------------------------------------------------------------------------

    Because regional haze is affected by natural and anthropogenic 
emissions from international sources, the WAQS 2011b modeling platform 
used a series of nested model simulations from the global to the 
regional scale. Global scale modeling was performed by the National 
Center for Atmospheric Research (NCAR) using the Model for OZone And 
Related chemical Tracers (MOZART).\53\ The WAQS 2011b used boundary 
concentrations data from the NCAR MOZART simulation to perform regional 
scale CAMx simulations using a coarse grid 36x36 km grid resolution for 
a model domain that included most of North America, a nested 12x12 km 
grid for a model domain that included all of the western U.S., and a 
fine scale 4x4 grid for a model domain that included the intermountain 
west region. The three nested CAMx modeling domains are illustrated in 
Figure 3.1 of WAQS 2011b model evaluation report.\54\
---------------------------------------------------------------------------

    \53\ The MOZART model formulation is described at https://en.wikipedia.org/wiki/MOZART_.
    \54\ Id. 56, p. 5.
---------------------------------------------------------------------------

    The PacifiCorp CAMx modeling was based on the WAQS 2011b 4x4 grid 
modeling domain, but PacifiCorp initially used a smaller modeling 
domain designed to focus on the nine Class I areas within 300 km of the 
Hunter and Huntington BART sources that had been used in previous Utah 
DEQ CALPUFF modeling.\55\ In response to comments from the EPA Region 
8, PacifiCorp expanded the size of their proposed 4x4 km grid modeling 
domain to ensure that air parcel trajectories would remain within the 
model domain as they were transported from the BART sources to the nine 
Class I areas. The expanded PacifiCorp 4x4 km model domain included 15 
Class I areas, as shown in Figure 6 of the Utah DEQ staff report.\56\ 
While some Class I areas are more than 300 km from the BART sources, 
CAMx is accurate for long range transport and has been used by the EPA 
for analysis of long range transport of ozone and fine particulates at 
distances greater than 1,000 km. For completeness, the EPA recommended 
that PacifiCorp evaluate model results for all 15 Class I areas in the 
CAMx modeling domain.
---------------------------------------------------------------------------

    \55\ Model applications using CALPUFF for BART sources 
typically--but not in all cases--have included Class I areas only up 
to a distance 300 km because uncertainty in CALPUFF results 
increases at distances greater than 300 km.
    \56\ Staff Review, Figure 6, p. 18.
---------------------------------------------------------------------------

    The EPA provides guidance for the use of photochemical grid models 
such as CAMx for evaluating source contributions to regional haze. 
Because this notice addresses requirements for BART sources as part of 
the first regional haze planning period, the model results are being 
evaluated using procedures designed specifically for these requirements 
as outlined in the RHR and in a EPA Guidance published in 2007.\57\ The 
RHR, 40 CFR 51.308(e)(3), requires that greater reasonable progress 
demonstrations for BART alternatives be evaluated for the best and 
worst 20% total haze days, which are selected for Class I areas using 
data from the IMPROVE monitoring network.\58\ The IMPROVE network 
consists of 110 monitoring sites designed to measure visibility 
impairment at the 155 mandatory Class I areas. While not all Class I 
areas have an IMPROVE monitor, the network was designed so that, where 
needed, measurements of one monitor would be representative of the 
regional haze conditions at more than one nearby Class I area.\59\
---------------------------------------------------------------------------

    \57\ Guidance for Setting Reasonable Progress Goals Under the 
Regional Haze Program, available at: https://www3.epa.gov/ttn/naaqs/aqmguide/collection/cp2/20070601_wehrum_reasonable_progress_goals_reghaze.pdf.
    \58\ The IMPROVE monitoring network is described at: http://vista.cira.colostate.edu/Improve/improve-program/.
    \59\ The use of a representative IMPROVE monitor for groups of 
nearby Class I areas is described at: http://vista.cira.colostate.edu/Improve/wp-content/uploads/2016/04/Chapter1.pdf.
---------------------------------------------------------------------------

    Because models can be subject to bias and error in the simulation 
of the individual components of PM2.5 that contribute to 
regional haze, the EPA guidance recommends that photochemical model 
results be used by multiplying the model simulated change in each 
component of PM2.5 by the PM2.5 concentration 
measured by the IMPROVE monitoring network. The EPA has developed 
software, the Speciated Model Attainment Test (SMAT), that can be used 
to calculate the model relative response factor (RRF) for each 
PM2.5 species in an emissions control simulation compared to 
a base case simulation, and to multiply the model RRF by the observed 
IMPROVE PM2.5 concentrations for a five year period at the 
representative monitor for each Class I area.
    As described in the model performance evaluation report for the 
WAQS 2011b platform, the model generally performed well at most sites 
in the western U.S. However, CAMx was biased low for ammonia and 
ammonium nitrate at some sites on the Colorado Plateau, i.e., CAMx 
predicted lower concentrations of ammonia and ammonium nitrate than 
were measured at some monitoring sites. Because model predictions for 
ammonium nitrate at these sites are directly relevant to the comparison 
of the ammonium nitrate- and ammonium sulfate-related visibility 
benefits of the BART and BART Alternative scenarios, the EPA 
recommended that PacifiCorp perform additional model sensitivity 
simulations and performance evaluation to improve model performance for 
ammonia and ammonium nitrate on the Colorado Plateau. The EPA 
recommended that ammonia concentration be increased at the northern 
boundary of the model domain, located in the Salt Lake City area. 
Previous winter PM2.5 modeling studies performed by Utah DEQ 
found that winter ammonia emissions were underestimated in the Cache 
Valley in northern UT, and that model performance for ammonium nitrate 
improved when ammonia emissions

[[Page 3568]]

were increased so that the model-simulated ammonia matched observed 
ammonia concentrations. For the sensitivity study, PacifiCorp used the 
Utah DEQ winter PM2.5 model results to define the ammonia 
concentrations at the northern boundary of the PacifiCorp modeling 
domain. Additionally, the EPA recommended changes to a model parameter 
that affects ammonia dry deposition to surfaces.\60\
---------------------------------------------------------------------------

    \60\ In an email dated 9/26/2017, Chris Emery of Ramboll, the 
developer of the CAMx model, identified an error in the model 
settings that caused it to overestimate the deposition and removal 
of gas phase ammonia in the model. The default model configuration 
included a setting that specified zero surface resistance to ammonia 
deposition which tends to overestimate ammonia deposition to 
surfaces and to underestimate the ambient concentrations of ammonia 
and ammonium nitrate. Mr. Emery recommended changing the model 
configuration to include surface resistance to ammonia deposition.
---------------------------------------------------------------------------

    PacifiCorp adopted both of these recommendations and performed a 
new base case model simulation and performance evaluation. This 
resulted in substantial improvements in model performance for ammonia 
and ammonium nitrate on the Colorado Plateau. Because the new base case 
model more accurately simulates the observed ammonia and ammonium 
nitrate concentrations, it is also expected to provide more accurate 
predictions of the visibility benefits of changes in NOX 
emissions for the EPA BART Benchmark and Utah NOX BART 
Alternative. These model results are described in Appendix A of the 
Utah DEQ Staff Review. The revised base case model configuration was 
then used for the 2011 Typical Year model simulation, the 2025 Baseline 
model simulation, and for the 2025 BART Benchmark and 2025 Utah 
NOX BART Alternative model simulations, described below.
    Using the WAQS 2011b platform, CAMx was configured to simulate the 
following modeling scenarios:
     2011 Typical Year. This 2011 scenario allows for the 
development of RRFs that are applied to observed concentrations in 
order to predict future visibility conditions. The Carbon, Hunter and 
Huntington power plants were modeled at levels representative of the 
period 2001 to 2003, while all other sources remain at the levels of 
the 2011 WAQS base year simulation.
     2025 Baseline. Emissions from Carbon, Hunter and 
Huntington are identical to the Typical Year modeling Scenario (i.e., 
2001-2003). All other emissions sources remain at the levels of the 
2025 WAQS future-year simulation.
     BART Benchmark. This 2025 scenario represents the BART 
Benchmark and simulates the emission control strategy for Hunter and 
Huntington units required in the 2016 FIP. Specifically, emissions for 
the four BART units reflect a 30-day rolling average NOX 
emission limit of 0.07 lb/MMBtu consistent with the installation and 
operation of SCR plus upgraded combustion controls. SO2 
emissions for the Hunter and Huntington units reflect representative 
emissions from 2014-2016 in order to match the BART Alternative 
scenario. The BART Benchmark scenario also includes the Carbon power 
plant using the same level of emissions as the Baseline scenario (i.e., 
2001-2003). All other emissions sources remain at the levels of the 
2025 WAQS future-year simulation.
     Utah NOX BART Alternative. This 2025 scenario 
simulates the emission control strategy for Carbon, Hunter and 
Huntington units required by the BART Alternative SIP as represented in 
Table 2 above. This scenario simulates representative emissions of 
NOX and SO2 from Hunter and Huntington units 
during the period 2014 to 2016, which include the emissions controls 
required under the Alternative (i.e., the upgraded combustion 
controls). For this scenario, the Carbon power plant emissions were 
zero since the power plant was decommissioned in April 2015, as 
required under the Alternative. All other emissions sources remain at 
the levels of the 2025 WAQS future-year simulation.
    All other model inputs, including other regional emissions sources, 
were held constant for the future-year (Baseline, BART Benchmark, and 
BART Alternative) scenarios. Thus, any differences in the visibility 
impacts between the modeled control scenarios and the Baseline, and 
between the two control scenarios (i.e., BART and the BART 
Alternative), are attributable solely to differences in the associated 
emission inputs for the seven PacifiCorp units. The CAMx-modeled 
concentrations for sulfate, nitrate, and other chemical species were 
tracked for the Hunter, Huntington, and Carbon power plants using the 
CAMx Particulate Source Apportionment Technology (PSAT) so that the 
concentrations and visibility impacts due to the seven PacifiCorp units 
could be separated out from those due to the total of all other modeled 
sources. Visibility impacts were assessed at the 15 Class I areas 
contained inside of the modeling domain.61 62
---------------------------------------------------------------------------

    \61\ Staff Review, pp. 17-18. Specifically, see rectangular CAMx 
modeling domain with 4-kilometer grid resolution in Figure 4-1.
    \62\ By contrast, in the CALPUFF modeling supporting EPA's 2016 
FIP, visibility impacts were assessed for the nine Class I areas 
within 300 kilometers of the BART units. The rectangular CAMx 
modeling domain was designed to be large enough to include these 
nine Class I areas and to include air parcel trajectories from those 
sources to the Class I areas. In response to EPA Region 8 comments 
on a draft modeling protocol, the rectangular CAMx model domain was 
expanded further to the east, north and south to ensure that 
emissions from the sources would remain within the model domain as 
they were transported from the sources to the affected Class I 
areas. For completeness, results for all Class I areas located 
within the rectangular CAMx domain were included in the analysis.
---------------------------------------------------------------------------

    The visibility impacts derived from the CAMx modeling results are 
summarized in Tables 4 and 5 of this notice.\63\ The tables show the 
projected contribution to visibility impairment due to emissions from 
the seven EGUs covered by the Alternative on the 20 percent best days 
and worst days respectively for the Baseline, the BART Benchmark, and 
the proposed BART Alternative scenarios at each of the Class I areas 
analyzed. The last two columns show the predicted visibility benefits 
from the BART Alternative scenario relative to both the Baseline and 
the BART Benchmark. At the bottom of each table are the average 
visibility values from all the Class I areas. Negative values in the 
last two columns indicate that the BART Alternative has smaller modeled 
contributions to visibility impairment relative to the Baseline and the 
BART Benchmark.
---------------------------------------------------------------------------

    \63\ Staff Review, pp. 16-21.
---------------------------------------------------------------------------

    Column D in Table 4 shows that emissions from the seven EGUs under 
the BART Alternative will not result in degradation of visibility on 
the 20 percent best days compared to the Baseline at any one of the 15 
Class I areas. Similarly, Column D in Table 5 shows that, on the 20 
percent worst days, visibility impairment is less under the BART 
Alternative than the Baseline in each of the Class I areas. Based on 
these results, the State concluded that visibility does not decline at 
any of the 15 Class I areas and therefore the BART Alternative meets 
prong 1 of the ``greater reasonable progress using dispersion 
modeling'' test found in 40 CFR 51.308(e)(3).
    The State next made a determination that the BART Alternative meets 
prong 2 of the ``greater reasonable progress using dispersion 
modeling'' test found in 40 CFR 51.308(e)(3) by comparing the average 
difference between the BART Alternative and the BART Benchmark.

[[Page 3569]]

The last row of column E in Tables 4 and 5 show the average difference 
in visibility between the BART Alternative and the BART Benchmark for 
the 20 percent best and worst days respectively. The negative number 
indicates that the average visibility improvement of the BART 
Alternative is better than the BART Benchmark in both cases. Relative 
to the BART Benchmark, the BART Alternative achieves an average 
visibility improvement of 0.00494 dv across all Class I areas on the 20 
percent best days, and of 0.00058 dv on the 20 percent worst days. 
Therefore, Utah determined that the BART Alternative meets prong 2 of 
the 40 CFR 51.308(e)(3) test.
    Utah noted that the language in 40 CFR 51.308(e)(3)(i) and (ii) 
indicates allowance of a straight numerical test. The State explained 
that the regulation does not specify that a minimum difference in 
deciview between the scenarios must be achieved to determine that a 
BART Alternative achieves greater reasonable progress. Because the 
modeling results show that visibility under the BART Alternative does 
not decline at any of the 15 affected Class I areas compared to the 
Baseline (prong 1) and will result in improved visibility, on average, 
across all 15 Class I areas compared to the BART Benchmark (prong 2), 
Utah asserted that the BART Alternative will achieve greater reasonable 
progress than the BART Benchmark under the two-prong modeling test in 
40 CFR 51.308(e)(3).

  Table 4--Visibility Impacts in 2025 for the Baseline, BART Benchmark and BART Alternative Scenarios on the 20
                                             Percent Best Days \64\
----------------------------------------------------------------------------------------------------------------
                                                                                                       BART
                                                  BART Benchmark       BART            BART        alternative--
          Class I area             Baseline (dv)       (dv)         alternative    alternative--       BART
                                                                       (dv)          baseline        benchmark
                                             [A]             [B]             [C]             [D]             [E]
----------------------------------------------------------------------------------------------------------------
Arches NP.......................         0.10300         0.05607         0.03851        -0.06449        -0.01756
Black Canyon of the Gunnison NM.         0.02769         0.01611         0.01162        -0.01607        -0.00449
Bryce Canyon NP.................         0.00528         0.00254         0.00228        -0.00300        -0.00026
Canyonlands NP..................         0.10300         0.05607         0.03851        -0.06449        -0.01756
Capitol Reef NP.................         0.14218         0.07222         0.07140        -0.07078        -0.00082
Flat Tops WA....................         0.02834         0.01488         0.01115        -0.01719        -0.00373
Grand Canyon NP.................         0.07136         0.03567         0.03611        -0.03525         0.00044
La Garita WA....................         0.02769         0.01611         0.01162        -0.01607        -0.00449
Maroon Bells-Snowmass WA........         0.02834         0.01488         0.01115        -0.01719        -0.00373
Mesa Verde NP...................         0.06356         0.03381         0.02749        -0.03607        -0.00632
Mount Zirkel WA.................         0.04209         0.02060         0.01471        -0.02738        -0.00589
San Pedro Parks WA..............         0.03627         0.01742         0.01593        -0.02034        -0.00149
Weminuche WA....................         0.02769         0.01611         0.01162        -0.01607        -0.00449
West Elk WA.....................         0.02834         0.01488         0.01115        -0.01719        -0.00373
Zion NP \1\.....................         0.00612         0.00291         0.00300        -0.00312         0.00009
All Class I area Average........         0.04940         0.02602         0.02108             N/A        -0.00494
----------------------------------------------------------------------------------------------------------------
\1\ Results based on incomplete dataset. Zion NP monitor did not meet the 75% data completion SMAT requirement
  for year 2011.

 Table 5--Visibility Impacts in 2025 for the Baseline, BART Benchmark, and BART Alternative Scenarios on the 20
                                             Percent Worst Days \65\
----------------------------------------------------------------------------------------------------------------
                                                                                                       BART
                                                  BART Benchmark       BART            BART        alternative--
          Class I area             Baseline (dv)       (dv)         alternative    alternative--       BART
                                                                       (dv)          baseline        benchmark
                                             [A]             [B]             [C]             [D]             [E]
----------------------------------------------------------------------------------------------------------------
Arches NP.......................         0.25740         0.13780         0.12584        -0.13156        -0.01196
Black Canyon of the Gunnison NM.         0.01265         0.00682         0.00540        -0.00725        -0.00142
Bryce Canyon NP.................         0.04945         0.02184         0.02470        -0.02475         0.00286
Canyonlands NP..................         0.25740         0.13780         0.12584        -0.13156        -0.01196
Capitol Reef NP.................         0.26010         0.11672         0.14568        -0.11442         0.02896
Flat Tops WA....................         0.02703         0.01387         0.01011        -0.01692        -0.00376
Grand Canyon NP.................         0.00186         0.00089         0.00056        -0.00130        -0.00033
La Garita WA....................         0.01265         0.00682         0.00540        -0.00725        -0.00142
Maroon Bells-Snowmass WA........         0.02703         0.01387         0.01011        -0.01692        -0.00376
Mesa Verde NP...................         0.06203         0.02524         0.02959        -0.03244         0.00435
Mount Zirkel WA.................         0.03312         0.01705         0.01198        -0.02114        -0.00507
San Pedro Parks WA..............         0.00154         0.00074         0.00073        -0.00081        -0.00001
Weminuche WA....................         0.01265         0.00682         0.00540        -0.00725        -0.00142
West Elk WA.....................         0.02703         0.01387         0.01011        -0.01692        -0.00376
Zion NP\1\......................         0.00155         0.00051         0.00051        -0.00104         0.00000
All Class I area Average........         0.06957         0.03471         0.03413             N/A        -0.00058
----------------------------------------------------------------------------------------------------------------
\1\ Results based on incomplete dataset. Zion NP monitor did not meet the 75% data completion SMAT requirement
  for year 2011.

[[Page 3570]]

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

    \64\ Staff Review, Table 4, p. 19.
    \65\ Staff Review, Table 5, p. 20.
---------------------------------------------------------------------------

    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. The RHR further provides 
that, ``[t]o meet this requirement, the State must provide a detailed 
description of the . . . alternative measure, including schedules for 
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.'' \66\
---------------------------------------------------------------------------

    \66\ 40 CFR 51.308(e)(2)(iii).
---------------------------------------------------------------------------

    As noted above, the December 3, 2019 supplement includes revisions 
to R307-110-17, the State rule that in turn incorporates Section IX, 
Control Measures for Area and Point Sources, Part H, Emissions Limits, 
which includes provisions for implementing the Utah NOX BART 
Alternative. In addition to the emission limitations for NOX 
and PM at Hunter and Huntington \67\ and the requirement for shutdown 
of the Carbon Plant listed in Table 1 above (which the State notes was 
made enforceable by August 15, 2015), the SIP submission includes 
compliance dates, operation and maintenance requirements, and MRR 
requirements. Utah asserts that the alternative measure was fully 
implemented prior to 2018.
---------------------------------------------------------------------------

    \67\ EPA previously approved the BART PM emission limits in our 
July 2016 final rule. 81 FR 43894 (July 5, 2016).
---------------------------------------------------------------------------

7. Demonstration That Emissions Reductions From Alternative Measure 
Will Be Surplus
    Pursuant to 40 CFR 51.308(e)(2)(iv), the SIP must demonstrate that 
the emissions 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. The 
baseline date for regional haze SIPs is 2002.\68\ Utah developed the 
2002 baseline inventory in its 2008 RH SIP for regional modeling, 
evaluating the impact on Class I areas outside of the Colorado Plateau, 
and BART as outlined in the EPA Guidance and the BART Guidelines, 
issued on July 6, 2005. Utah noted that 2002 is the baseline inventory 
that was used by other states throughout the country when evaluating 
BART under the provisions of 40 CFR 51.308 and that any measure adopted 
after 2002 is considered ``surplus'' under 40 CFR 51.308(e)(2)(iv). 
Utah referenced other EPA actions that are consistent with this 
interpretation.\69\ Utah stated that the BART Benchmark scenario 
includes measures required before the baseline date of the SIP (i.e., 
2002) but does not include later measures that are credited as part of 
the BART Alternative scenario.
---------------------------------------------------------------------------

    \68\ See Memorandum from Lydia Wegman and Peter Tsirigotis, 2002 
Base Year Emission Inventory SIP Planning: 8-hr Ozone, 
PM2.5, and Regional Haze Programs (Nov. 18, 2002), 
available at https://www3.epa.gov/ttn/naaqs/aqmguide/collection/cp2/20021118_wegman_2002_base_year_emission_sip_planning.pdf.
    \69\ E.g., 79 FR 33438, 33441-33442 (June 11, 2014); 79 FR 
56322, 56328 (Sept. 9, 2014).
---------------------------------------------------------------------------

    Utah explained that, to address potential concerns with double 
counting SO2 emission reductions from the Carbon plant 
closure under both the 308 and 309 programs, the July 2019 SIP 
submission includes revisions to the applicability provisions of State 
Rule State Rule R307-150, Emission Inventories, to prevent double 
counting. Utah also provided explanation why the emission reductions 
counted towards the NOX BART Alternative are surplus to 
those needed to satisfy the requirements of the SO2 Backstop 
Trading Program.\70\ The State explained that the WRAP modeling done to 
support the Utah RH backstop trading program SIP included regional 
SO2 emissions based on the 2018 SO2 milestone and 
also included NOX and PM emissions from the Carbon plant. 
Actual emissions in the three-state region (Utah, Wyoming, and New 
Mexico) are calculated each year and compared to the milestones. Utah 
provided the information in Table 6 below to show that since 2011, 
SO2 emissions in the three-state region have been below the 
2018 milestone (141,849 tpy). Utah noted that the most recent milestone 
report for 2016 demonstrates that SO2 emissions are 
currently 36 percent lower than the 2018 milestone. Utah stated that 
the Carbon plant was fully operational in the years 2011-2013 when the 
2018 milestone was initially achieved for those years. The State noted 
that the SO2 emission reductions from the closure of the 
Carbon plant are surplus to what is needed to meet the 2018 milestone 
established in Utah's RH SIP.
---------------------------------------------------------------------------

    \70\ Staff Review at 23-25.

                                       Table 6--SO2 Milestone Trends \71\
----------------------------------------------------------------------------------------------------------------
                                                                                   Three-year
                                                                                  average SO2      Carbon plant
                             Year                              Milestone (tpy)   emissions \1\    SO2 emissions
                                                                                     (tpy)            (tpy)
----------------------------------------------------------------------------------------------------------------
2003.........................................................          303,264          214,780            5,488
2004.........................................................          303,264          223,584            5,642
2005.........................................................          303,264          220,987            5,410
2006.........................................................          303,264          218,499            6,779
2007.........................................................          303,264          203,569            6,511
2008.........................................................          269,083          186,837            5,057
2009.........................................................          234,903          165,633            5,494
2010.........................................................          200,722          146,808            7,462
2011.........................................................          200,722          130,935            7,740
2012.........................................................          200,722          115,115            8,307
2013.........................................................          185,795          105,084            7,702
2014.........................................................          170,868           96,302            9,241
2015.........................................................          155,940           91,310            2,816
2016.........................................................          155,940           90,591                0
2017.........................................................          155,940  ...............  ...............
2018.........................................................          141,849  ...............  ...............
----------------------------------------------------------------------------------------------------------------
\1\ The three-year average is based on the emissions averaged for the current and two preceding years.

[[Page 3571]]

    For Hunter Unit 3, Utah also explained that PacifiCorp upgraded the 
LNB controls in 2008 and that the upgrade was not required under any 
applicable requirements of the CAA as of the 2002 baseline date of the 
SIP; the emission reductions from the upgrade are therefore considered 
surplus and creditable for the BART Alternative under 40 CFR 
51.308(e)(2)(iv). Utah noted that prior to the 2008 upgrade, the 
emission rate for Hunter Unit 3 was 0.46 lb/MMBtu on a 30-day rolling 
average as required by Phase II of the Acid Rain Program.\72\
---------------------------------------------------------------------------

    \71\ Staff Review, p 24.
    \72\ There is an error on page 25 of the Staff Review. The 
reference to Hunter Unit 2 should be Unit 3 based on the section 
heading as well as confirmed emission limits in Utah Approval Order 
DAQE-AN0102370012-08.
---------------------------------------------------------------------------

    To address potential concerns that Utah would be double counting 
SO2 emissions reductions for the Carbon plant closure under 
both the 40 CFR 51.308 and 309 programs, the July 2019 SIP revisions 
require that the State continue to report the historical emissions for 
the Carbon plant in the annual milestone reports. Specifically, 
revisions to the applicability provisions of State rule R307-150 
(``Emission Inventories Program'') require that Utah include emissions 
of 8,005 tons/yr \73\ of SO2 for the Carbon Power Plant in 
the annual milestone reports.
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    \73\ Note that this value is based on the 2012-2013 actual 
annual average SO2 emissions for the Carbon power plant 
as used in Utah's June 4, 2015 SIP submission. By contrast, Utah's 
July 3, 2019 SIP submission uses a consistent baseline for Hunter, 
Huntington and Carbon based on actual annual average emissions from 
2001-2003 when the SO2 emissions for Carbon were 5,814 
tons/year. That is, the revisions to the SO2 milestone 
reporting requirements attribute a greater amount of tons of 
SO2 to the Carbon plant than the State assumed will be 
reduced from the plant's retirement, for purposes of making the 
demonstration that the BART Alternative achieves greater reasonable 
progress than BART. As such, Utah's analysis of its compliance with 
the SO2 milestone as well as its demonstration of greater 
reasonable progress for the BART Alternative are both conservative.
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C. Monitoring, Recordkeeping and Reporting

    To address EPA's partial disapproval of the 2011 Utah RH SIP for 
lack of enforceable measures and MRR requirements,\74\ in 2015 Utah 
added two new subsections to SIP Sections IX, H.21 (General 
Requirements: Control Measures for Area and Point Sources, Emission 
Limits and Operating Practices, Regional Haze Requirements) and H.22 
(Source Specific Emission Limitations: Regional Haze Requirements, Best 
Available Retrofit Technology).
---------------------------------------------------------------------------

    \74\ 77 FR 28825, 28842 (May 16, 2012).
---------------------------------------------------------------------------

    Specifically, to remedy the SIP's lack of provisions for ensuring 
that emission limits are practically enforceable, under H.21 Utah added 
a new definition for boiler operating day. Utah noted that state rules 
R307-107-1 and R307-107-2 (applicability, timing, and reporting of 
breakdowns) apply to sources subject to regional haze requirements 
under H.22. Utah required that information used to determine compliance 
shall be recorded for all periods when the source is in operation, and 
that such records shall be kept for a minimum of five years. Under 
H.21, Utah specified that emission limitations listed in H.22 shall 
apply at all times and identified stack testing requirements to show 
compliance with those emission limitations. Finally, H.21 also 
specifies the requirements for continuous emission monitoring by 
listing the requirements and cross-referencing the State's rule for 
continuous emission monitoring system requirements, R307-170, as well 
as 40 CFR 13 \75\ and 40 CFR 60, appendix B--Performance 
Specifications. Utah included the requirements to calculate hourly 
average NOX concentrations for any hour in which fuel is 
combusted and a new 30-day rolling average emission rate at the end of 
each boiler operating day. Utah also noted that the hourly average 
NOX emission rate is valid only if the minimum number of 
data points specified in R307-170 is acquired for both the pollutant 
concentration monitor and diluent monitor.
---------------------------------------------------------------------------

    \75\ This appears to be a typo, and the correct reference should 
be to 40 CFR 60.13.
---------------------------------------------------------------------------

    Under H.22, Utah provided the emission limitations associated with 
the NOX BART Alternative and PM BART for Hunter Units 1 
through 3 and Huntington Units 1 and 2, a requirement to perform annual 
stack testing for PM, and a requirement to measure NOX via 
continuous emission monitoring for the sources covered under the Utah 
NOX BART Alternative. Under H.22, Utah also listed the 
enforceable conditions related to closing Carbon Units 1 and 2 by 
August 15, 2015, including PacifiCorp's and Utah's notification and 
permit rescission obligations.
    In our 2016 final rule, EPA approved subsection H.21 and H.22 as 
they pertain to PM BART, including conditional approval of the 
reporting requirements. We did not act on the elements of those 
subsections relating to the NOX BART Alternative, as EPA 
disapproved the Alternative in that action. Utah resubmitted 
subsections H.21 and H.22 as part of their July 3, 2019 SIP submittal. 
In its December 3, 2019 supplemental submission, to address the issue 
implicated in the conditional approval, under H.21(e) Utah required 
each source to submit a report of any deviation from applicable 
emission limits and operating practices, including deviations 
attributable to upset conditions, the probable cause of such 
deviations, and any corrective actions or preventive measures taken.

D. Consultation With FLMs

    Utah's SIP submittals do not specifically discuss how it addressed 
the requirements of 40 CFR 308(i)(2) for providing the FLMs with an 
opportunity for consultation at least 60 days prior to holding the 
public hearing for the July 2019 RH SIP. However, we are aware that 
Utah consulted with the FLMs as explained in section IV.D, and the 
relevant exchange is included in the docket for this action.

IV. EPA's Evaluation and Proposed Approval of Utah's Regional Haze SIP

A. Basis for Proposed Approval

    For the reasons described below, EPA proposes to approve the Utah 
2019 RH SIP revisions. Our proposed action is based on an evaluation of 
Utah's regional haze SIP submittals against the regional haze 
requirements at 40 CFR 51.300-51.309 and CAA sections 169A and 169B. 
The revisions were also evaluated against the general SIP requirements 
contained in CAA section 110, other provisions of the CAA, and our 
regulations applicable to this action. The EPA proposes to approve 
these SIP revisions as meeting the relevant CAA requirements. Where 
appropriate, we provide additional rationale to supplement to the 
state's analysis and to support our conclusions below.

B. Demonstration of Greater Reasonable Progress for the Alternative 
Program

    As provided under 40 CFR 51.309(d)(4)(vii), Utah has opted to 
establish an alternative measure (or program) for NOX 
emissions from the four subject-to-BART units in accordance with 40 CFR 
51.308(e)(2). A description of the Utah NOX BART Alternative 
is provided above in section III.A.1. The RHR requires that a SIP 
revision establishing a BART alternative meet three key requirements 
(in addition to other elements in section 308(e)(2)) as listed below. 
We have evaluated the Utah NOX BART Alternative with respect 
to each of these requirements.
     A demonstration that the emissions trading program or 
other 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

[[Page 3572]]

State and covered by the alternative program.\76\
---------------------------------------------------------------------------

    \76\ 40 CFR 51.308(e)(2)(i).
---------------------------------------------------------------------------

     A requirement that all necessary emissions reductions take 
place during the period of the first long-term strategy for regional 
haze.\77\
---------------------------------------------------------------------------

    \77\ 40 CFR 51.308(e)(2)(iii).
---------------------------------------------------------------------------

     A demonstration that the emissions 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.\78\
---------------------------------------------------------------------------

    \78\ 40 CFR 51.308(e)(2)(iv).
---------------------------------------------------------------------------

    As discussed above in section II.C, pursuant to 40 CFR 
51.308(e)(2)(i), Utah 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 
has five parts, each of which is addressed in the July 2019 SIP 
submittal, including the Staff Review support document.
1. List of All BART-Eligible Sources Within the State
    As discussed above in section III.B.1, Utah included a list of all 
BART-eligible sources:

 PacifiCorp Hunter, Unit 1
 PacifiCorp Hunter, Unit 2
 PacifiCorp, Huntington, Unit 1
 PacifiCorp, Huntington, Unit 2

    EPA previously approved Utah's BART eligibility determinations in 
our 2012 rulemaking,\79\ and we are now proposing that this same list 
satisfies the requirements of 40 CFR 51.308(e)(2)(i)(A).
---------------------------------------------------------------------------

    \79\ 77 FR 74355, 74357 (Dec. 14, 2012).
---------------------------------------------------------------------------

2. List of All BART-Eligible Sources and All BART Source Categories 
Covered by the Alternative Program
    As discussed above in section III.B.2, the Utah NOX BART 
Alternative covers all of the BART-eligible sources in the State, 
Hunter Units 1 and 2 and Huntington Units 1 and 2, in addition to three 
non-BART units, PacifiCorp's Hunter Unit 3 and Carbon Units 1 and 2. We 
propose that Utah has satisfied the requirement of 40 CFR 
51.308(e)(2)(i)(B).
3. Analysis of BART and Associated Emission Reductions
    As noted above in section III.B.3, in the July 2019 Utah RH SIP 
submittal, the State compared the Utah NOX BART Alternative 
to a BART Benchmark that included the most stringent NOX 
BART controls, SCR plus upgraded combustion controls, at the four BART 
units. While the State explicitly noted that it was not determining 
that SCR plus upgraded combustion controls would constitute source-
specific BART at the four subject-to-BART units, it explained that this 
technology ``can be used as a stringent benchmark for comparison with 
an alternative program'' and it is ``a conservative approach.'' \80\ We 
are proposing to find that this is a reasonable approach to setting the 
BART Benchmark for purposes of comparison to a BART alternative 
program, and is consistent with the streamlined approach described in 
Step 1 of the BART Guidelines. The BART Guidelines note that a 
comprehensive BART analysis can be forgone if a source adopts the most 
stringent controls available for the purpose of implementing BART.\81\ 
Moreover, when EPA established NOX BART in our 2016 FIP, we 
also selected SCR plus upgraded combustion controls (with an emission 
limit of 0.07 lb/MMBtu as a 30-day rolling average), which further 
reinforces the reasonableness of Utah's decision to treat the most 
stringent controls as the BART Benchmark.
---------------------------------------------------------------------------

    \80\ Staff Review at 12.
    \81\ 40 CFR 51, appendix Y, section IV.D.1.9.
---------------------------------------------------------------------------

    Utah then used modeling projections for the year 2025 to determine 
the associated emission reductions that would result under the BART 
Benchmark. These results are provided above in Table 2 of this notice. 
The EPA proposes to find that the methodology Utah used to develop the 
projection of emissions under the BART Benchmark is reasonable because 
it reflects the most stringent control option.
    We propose to find that Utah has met the requirement for an 
analysis of BART and associated emission reductions achievable at 
Hunter Units 1 and 2 and Huntington Units 1 and 2 under 40 CFR 
51.308(e)(2)(i)(C).
4. Analysis of Projected Emissions Reductions Achievable Through the 
BART Alternative
    Utah's NOX BART Alternative consists of the following 
enforceable measures:
     A NOX emission limit of 0.26 lb/MMBtu (30-day 
rolling average) each for Hunter Units 1 and 2 and Huntington 1 and 2.
     A NOX emission limit of 0.34 lb/MMBtu (30-day 
rolling average) for Hunter Unit 3.
     A requirement to permanently close and cease operation of 
the Carbon power plant by August 15, 2015.
    As discussed above in section III.B.4, a summary of Utah's 
estimates of emissions for the Utah NOX BART Alternative and 
the BART Benchmark is provided above in Table 2. Note that the values 
in Table 2 differ from the analogous table in our 2016 proposed rule 
\82\ for the following reasons. First, in addition to the BART 
Benchmark and BART Alternative, the table now includes projections for 
the Baseline emissions scenario. All three of these projected 2025 
scenarios relate to the CAMx modeling used to demonstrate that the BART 
Alternative will achieve greater progress than BART under the two-prong 
test of 40 CFR 51.308(e)(3), as discussed in sections III.B.5 and 
IV.B.5 of this notice. The 2025 Baseline is used in the first prong of 
the two-prong test to demonstrate that visibility under the BART 
Alternative does not decline at any of the 15 affected Class I areas. 
Second, to ensure that the selection of baseline emissions does not 
bias the determination of whether the BART Alternative achieves greater 
reasonable progress, the projected emissions for all three 2025 
scenarios are calculated from a consistent baseline of 2001-2003 for 
all BART-eligible and non-BART units covered by the BART Alternative. 
That is, when establishing emission assumptions for the 2011 Typical 
Year modeling scenario, annual emission rates for the seven units were 
set equal to 2001-2003 actual average emissions, and these annual 
emission rates were then projected to 2025 to reflect the 
NOX controls anticipated under each future year scenario. 
Note that although the 2025 Baseline scenario is a projection of 2025 
emissions for all other sources in the modeling domain, the Baseline 
emissions for the seven units in Table 2 reflect 2001-2003 emissions. 
This approach was chosen so that the 2025 Baseline reflects emissions 
at the subject-to-BART units at the Hunter and Hunter power plants 
prior to the installation of any controls or other measures intended to 
meet BART requirements. Finally, the 2001-2003 baseline period also 
aligns with that used by EPA in our evaluation of BART under the FIP in 
our 2016 final rule.
---------------------------------------------------------------------------

    \82\ Table 3; 81 FR 2015.
---------------------------------------------------------------------------

    Relative to the 2025 Baseline, the BART Benchmark and BART 
Alternative include actual SO2 reductions from Hunter and 
Huntington that occurred after the 2001-2003 baseline due to scrubber 
upgrades. Thus, the CAMx modeling results for the BART Benchmark and 
BART Alternative shown in Tables 4 and 5 of this notice reflect these 
SO2 reductions. The treatment of these SO2 
reductions in the modeling does not affect the determination of greater 
reasonable

[[Page 3573]]

progress under the two-prong test. Under prong 1, while the 
SO2 reductions from Hunter and Huntington increase the 
apparent overall visibility benefit of the BART Alternative relative to 
the Baseline, there would not be an anticipated decline in visibility 
relative to the Baseline in the absence of those SO2 
reductions from Hunter and Huntington because the BART Alternative 
would still result in overall NOX, SO2, and PM 
emissions decreases compared to the Baseline. Under prong 2, because 
the SO2 reductions from Hunter and Huntington are equal 
under the BART Alternative and BART Benchmark, they do not advantage 
either control scenario. Accordingly, the EPA proposes to find that the 
methodology Utah used to develop the modeling scenarios, including the 
projection of emissions under the Utah NOX BART Alternative, 
is reasonable and that Utah has met the requirement for an analysis of 
the projected emissions reductions achievable through the alternative 
measure under 40 CFR 51.308(e)(2)(i)(D).
5. Determination That the Alternative Achieves Greater Reasonable 
Progress Than Would Be Achieved Through the Installation and Operation 
of BART
    As discussed above in section III.B.5, Utah used CAMx modeling to 
assess whether the NOX BART alternative will achieve greater 
reasonable progress than the BART Benchmark under the two-prong 
quantitative test provided for in 40 CFR 51.308(e)(3)(i) and (ii). The 
CAMx modeling results in Tables 4 and 5 show both prongs of the two-
prong test are satisfied: Visibility does not decline in any Class I 
area under the BART Alternative relative to the Baseline on both the 
20% best or 20% worst days, and the average visibility improvement 
across all affected Class I areas is greater under the BART Alternative 
than under the BART Benchmark. EPA reviewed the CAMx protocol before 
the modeling was undertaken. PacifiCorp revised the modeling methods 
and assumptions to address EPA's concerns. Notably, as discussed above 
in section III.B.5, PacifiCorp revised the ammonia emission inventory 
and related input parameters to improve the model's ability to simulate 
ammonia and ammonium nitrate concentrations on the Colorado Plateau, 
thus also improving the model's ability to estimate visibility impacts 
resulting from NOX emissions. In addition, the analysis was 
expanded to assess all 15 class I areas in the modeling domain.
    As noted above, Utah submitted the same proposed NOX 
BART Alternative in its June 2015 submission under the qualitative 
clear-weight-of-evidence test in 40 CFR 51.308(e)(2)(i)(E). In July 
2016, EPA determined that, based on the weight-of-evidence 
demonstration before us at that time, Utah had not demonstrated that 
the BART Alternative resulted in greater visibility improvement than 
would BART. However, as noted by the U.S. Court of Appeals for the 
Tenth Circuit, under EPA's interpretation of its regulations a state 
can choose either the quantitative tests (as applicable) in 
51.308(e)(3) or the qualitative test in 51.308(e)(2)(i)(E).\83\ We 
believe it follows that a reasonable interpretation of our regulatory 
scheme allows for a situation in which certain evidence would not be 
sufficient to make a showing under one ``better-than-BART'' test, but 
different evidence could support that showing under a separate test. 
That is, we believe that just because a certain set of evidence failed 
to show that a BART alternative would achieve greater visibility 
improvement under the ``clear weight of evidence'' test, that does not 
necessarily mean that the alternative does not in fact make greater 
reasonable progress than BART, as demonstrated through dispersion 
modeling under the two-prong test in section 308(e)(3). Accordingly, we 
propose to approve Utah's determination that the Utah NOX 
BART Alternative would achieve greater reasonable progress than BART 
under 40 CFR 51.308(e)(3).
---------------------------------------------------------------------------

    \83\ WildEarth Guardians v. EPA, 770 F.3d 919, 934 (10th Cir. 
2014).
---------------------------------------------------------------------------

6. Requirement That Emission Reductions Take Place During Period of 
First Long-Term Strategy
    As discussed above in section III.B.6, 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. The RHR further provides that, to meet this 
requirement, the State must provide a detailed description of the 
alternative measure, including schedules for 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.\84\
---------------------------------------------------------------------------

    \84\ 40 CFR 51.308(e)(2)(iii).
---------------------------------------------------------------------------

    The NOX controls on which the BART Alternative relies 
were installed at Hunter and Huntington over a period of years starting 
in 2006 and finishing in 2014.\85\ The associated emissions limits were 
effective upon installation of the NOX controls.\86\ Carbon 
shut down in 2015 and its Approval Order has been revoked.\87\ Further, 
as noted above, the Utah SIP submittals include revisions to R307-110-
17 and Section IX, Control Measures for Area and Point Sources, Part H, 
Emissions Limits, which include enforceable provisions for implementing 
the Utah NOX BART Alternative. In addition to the emission 
limitations for NOX and PM, and the requirement for shutdown 
of the Carbon plant listed in Table 1 above, the SIP includes 
compliance dates, operation and maintenance requirements, and 
monitoring, recordkeeping, and reporting requirements. We propose to 
find that these provisions meet the requirements of 40 CFR 
51.308(e)(2)(iii).
---------------------------------------------------------------------------

    \85\ Refer to the Staff Report, Table 6, Implementation 
Schedule.
    \86\ Hunter Power Plant Approval Order: Installation of 
Pollution Control Equipment, Established Plantwide Applicability 
Limitations and Approval Orders Consolidation, Emery County--CDS A; 
NSPS; PSD; Title IV; Title V Major; HAPs, March 13, 2018; Huntington 
Plant Approval Order: Installation of Pollution Control Equipment 
and Establishing Plant-wide Applicability Limitations, Emery County; 
CDS A; NSPS (Part 60), PSD, Title IV (Part 72/Acid Rain), Title V 
(Part 70), Project Number: N010238-0019 (August 6, 2009).
    \87\ Letter from Utah Department of Environmental Quality, 
Division of Air Quality, to PacifiCorp, Re: Revocation of Approval 
Order DAQE-ANO 100810005-08 dated May 16, 2008, Project Number: 
N10081-0007, January 8, 2016.
---------------------------------------------------------------------------

7. Demonstration That Emission Reductions From Alternative Measure Will 
Be Surplus
    As discussed above in section III.B.7, pursuant to 40 CFR 
51.308(e)(2)(iv), the SIP must demonstrate that the emissions 
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. The baseline date for 
regional haze SIPs is 2002.\88\ As discussed in section III.B.7, all of 
the emission reductions required by the Utah NOX BART 
Alternative result from measures applicable to Hunter, Huntington and 
Carbon that were required pursuant to measures adopted after 2002.
---------------------------------------------------------------------------

    \88\ 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 18, 2002. 
https://www3.epa.gov/ttn/naaqs/aqmguide/collection/cp2/20021118_wegman_2002_base_year_emission_sip_planning.pdf.
---------------------------------------------------------------------------

    Furthermore, the State's SIP explains that the WRAP modeling for 
the 2018 Reasonable Progress Goals that was done to support the Utah RH 
SIP assumed that Carbon would still be operating and emitting 
SO2 when it

[[Page 3574]]

modeled the 2018 SO2 milestone; the modeling also included 
NOX and PM emissions from the Carbon plant. Thus, WRAP did 
not rely on post-2002 emission reductions from the Carbon plant in 
establishing the 2018 SO2 milestone.
    The State's SIP also includes SO2 trend data that 
further demonstrate emission reductions from the Carbon plant are most 
likely not needed for meeting the three-state 2018 milestone of 141,849 
tpy. Actual emissions in the three-state region are calculated each 
year and compared to the milestones. As can be seen in Table 6 above, 
SO2 emissions reported each year since 2011 were below the 
2018 milestone and the most recent milestone report for 2016 
demonstrates that SO2 emissions are currently 36 percent 
lower than the 2018 milestone. The Carbon plant was fully operational 
in the years 2012-2014 when the emissions from the three-state region 
were below the milestone for those years. In its amendments to the 
Backstop Trading Program to ensure there would be no double-counting of 
SO2 emission reductions from the Carbon plant closure, the 
State attributed 8,005 tons of SO2 emissions to the Carbon 
plant for purposes of demonstrating that even if Carbon continued to 
emit at that level, the three-state region would still be well below 
the 2018 Milestone. Therefore, the SO2 emission reductions 
from the closure of the Carbon plant are surplus to what is needed to 
meet the 2018 milestone established in Utah's RH SIP, and can therefore 
be credited to the Utah NOX BART Alternative.
    As discussed above in section III.B.7, the amendments to the 
applicability provisions of State rule R307-150-3, Emissions 
Inventories, Applicability, ensure that there is no double counting 
SO2 emissions reductions for the Carbon plant closure under 
both the 40 CFR 51.308 and 309 programs.
    We propose to concur that the reductions from Carbon are surplus 
and can be considered as part of an alternative strategy under 40 CFR 
51.308(e)(2)(iv). We also propose to approve Utah's revision to R307-
150-3, amending the SO2 emissions reported under the 
milestone, which ensures that these reductions are not double counted.

C. Monitoring, Recordkeeping, and Reporting

    EPA has reviewed the MRR measures in Utah's July 3, 2019 SIP 
submittal, as supplemented on December 3, 2019, which revises Section 
IX, Part H, of Utah's SIP, and which apply for units subject to the 
NOX BART Alternative and PM BART. EPA proposes to approve 
these measures as meeting the requirements of section 110(a)(2) of the 
CAA and 40 CFR part 51, subpart K, Source Surveillance, and 40 CFR part 
51, appendix V. Generally, these provisions require that SIPs must 
contain enforceable emission limitations and schedules for compliance, 
including MRR provisions that allow for the enforcement of those 
emission limitations. EPA previously approved state rule provisions 
that Utah has cross-referenced in these new regional haze measures, 
including terms, conditions and definitions in R307-101-1 (General 
Requirements--Forward), R307-101-2 General Requirements--Definitions), 
and R307-170-4 (Continuous Emission Monitoring Program--Definitions), 
as well as other continuous emission monitoring system (CEMS) 
requirements referenced in R307-107. These measures contain the 
requirements that were missing from Utah's prior regional haze 
submittals \89\ and are furthermore consistent with similar MRR 
requirements that EPA has approved for other states RH SIPs or that we 
have adopted in federal implementation plans.\90\ As described above in 
section III.C, Utah has provided the emission limitations, MRR 
requirements for all the units that are part of Utah's BART Alternative 
for the Hunter, Huntington, and Carbon plants, and we are proposing to 
approve these provisions as satisfying CAA section 110(a)(2), 40 CFR 
part 51, subpart K, and 40 CFR part 51, appendix V with regard to MRR 
requirements to make emission limitations in the SIP practically 
enforceable.
---------------------------------------------------------------------------

    \89\ 77 FR 74365-74366 (Dec. 14, 2012).
    \90\ See, e.g., 77 FR 57864 (Sept. 18, 2012); 79 FR 5032 (Jan. 
30, 2014).
---------------------------------------------------------------------------

D. Consultation With FLMs

    On December 19, 2018, the State provided the opportunity for the 
FLMs to review the preliminary draft SIP documents. This was 
approximately 120 days prior to the public hearing that was held on 
April 17, 2019, and prior to the public comment period for the proposed 
SIP revisions submitted to EPA in July 2019, which ran from April 1 
through May 15, 2019. The FLMs did not submit comments prior to or 
during the public comment period. Copies of the correspondence 
documenting the State's outreach to the FLMs are included in the 
docket. We propose to find that Utah has met the requirements of 40 CFR 
308(i)(2).

V. Clean Air Act 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 (as defined in 
section 7501 of this title), or any other applicable requirement of 
this chapter.'' \91\ We propose to find that these revisions satisfy 
section 110(l). The previous sections of the notice explain how the 
proposed SIP revision and FIP withdrawal will comply with applicable 
regional haze requirements and general implementation plan requirements 
such as enforceability. With respect to requirements concerning 
attainment and reasonable further progress, the Utah Regional Haze SIP, 
as revised by this action, will allow for greater NOX 
emissions at the four subject-to-BART units as compared to the 2016 FIP 
(which is currently judicially stayed). The change in these emissions 
compared to the FIP, however, is not anticipated to interfere with any 
applicable requirements under the CAA. The geographic area where the 
BART units are located is not part of a nonattainment area for any 
National Ambient Air Quality Standards (NAAQS). The approved portions 
of the PM2.5 attainment demonstrations and clean data 
determinations (CDD) for the Salt Lake City, Provo, and Logan, UT-ID 
nonattainment areas (NAAs) do not rely on the installation of SCR at 
Hunter or Huntington to achieve attainment of the NAAQS. Similarly, the 
approved PM10 attainment demonstrations for Salt Lake County 
and Utah County NAAs, and CDD for Ogden City NAA do not rely on the 
installation of SCR at Hunter or Huntington to achieve attainment of 
the NAAQS. In addition, there are no other approved attainment 
demonstrations in other areas of the State or outside of the State that 
rely on the installation of SCR at Hunter or Huntington to achieve 
attainment of any of the NAAQS.
---------------------------------------------------------------------------

    \91\ 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 National Ambient Air Quality Standards 
(NAAQS) set for criteria pollutants under CAA 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 EPA 
cannot approve plan revisions that interfere with regional haze 
requirements (including reasonable progress requirements) insofar as 
they are ``other applicable requirement[s]'' of the Clean Air Act.

---------------------------------------------------------------------------

[[Page 3575]]

VI. The EPA's Proposed Action

A. 2019 Utah Regional Haze SIP Revision

    We are proposing to approve these aspects of the 2019 Utah RH SIP 
revisions:
     NOX BART Alternative, including NOX 
emission reductions from Hunter Units 1, 2, and 3 and Huntington Units 
1 and 2, and SO2, NOX and PM emission reductions 
from Carbon Units 1 and 2.
     A NOX emission limit of 0.26 lb/MMBtu (30-day 
rolling average) each for Hunter Units 1 and 2 and Huntington 1 and 2.
     A NOX emission limit of 0.34 lb/MMBtu (30-day 
rolling average) for Hunter Unit 3.
     A requirement to permanently close and cease operation of 
the Carbon power plant by August 15, 2015.
     The associated amendments to the SO2 milestone 
reporting requirements.
     MRR requirements for units subject to the NOX 
BART Alternative and the PM BART emission limits.
    We also note that the regulatory text amendments contained in this 
notice include incorporation of additional parts of SIP section XX 
(XX.B-C and XX.E-N) and section XXIII, which were not addressed in this 
proposed action. EPA approved these SIP sections as meeting the 
requirements of the CAA and applicable regulations in previous actions; 
\92\ however, we inadvertently did not incorporate all approved 
sections in 40 CFR 52.2320(e). We are remedying this oversight and 
reorganizing 40 CFR 52.2320(e) to better reflect the structure of 
Utah's SIP submissions here; however, we are not reopening any of these 
previously approved SIP sections for comment.
---------------------------------------------------------------------------

    \92\ 73 FR 16543 (Mar. 28, 2008); 77 FR 74355 (Dec. 14, 2012); 
78 FR 4072 (Jan. 18, 2013); 81 FR 43894 (July 5, 2016).
---------------------------------------------------------------------------

    Finally, contingent on our approval of Utah's July 2019 and 
December 2019 SIP submissions, we propose to find that Utah's SIP fully 
satisfies the requirements of section 309 of the RHR and therefore the 
State has fully complied with the requirements for reasonable progress, 
including BART, for the first implementation period.

B. FIP Withdrawal

    Because we are proposing to find that Utah's July 2019 and December 
2019 SIP submissions satisfy the NOX BART and MRR 
requirements currently addressed by EPA's 2016 FIP, we are also 
proposing to withdraw in whole the Utah Regional Haze FIP at 40 CFR 
52.2336 that imposes NOX BART requirements on Hunter Units 1 
and 2 and Huntington Units 1 and 2.

C. Clean Air Section 110(l)

    We are proposing to find that an approval of the 2019 Utah RH SIP 
revisions and concurrent withdrawal of the corresponding the FIP, as 
proposed, complies with the CAA's 110(1) provisions.
    We are requesting comment on the proposed actions in section VI.A-
C, i.e., on our proposed approval of Utah's NOX BART 
Alternative and of the MRR elements for the units subject the BART 
Alternative and to PM BART. We are not reopening or requesting comment 
on any of the previously approved elements of Utah's regional haze SIP, 
except to the extent expressly reopened in this notice. If we finalize 
our approval of the July 2019 and December 2019 regional haze SIP 
submittals, Utah's regional haze SIP for the first implementation 
period will be fully approved.

VII. Incorporation by Reference

    In this document, EPA is proposing to include regulatory text in an 
EPA final rule that includes incorporation by reference. In accordance 
with the requirements of 1 CFR 51.5, EPA is proposing to incorporate by 
reference the SIP amendments described in Sections III.A and VI.A of 
this preamble and set forth below. The EPA has made, and will continue 
to make, these materials generally available through 
www.regulations.gov (refer to docket EPA-R08-OAR-2015-0463) and at the 
EPA Region 8 Office (please contact the person identified in the For 
Further Information Contact section of this preamble for more 
information).

VIII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    This action is not a ``significant regulatory action'' under the 
terms of Executive Order 12866 \93\ and was therefore not submitted to 
the Office of Management and Budget (OMB) for review. This proposed 
rule applies to only 7 units at three facilities in Utah that are 
individually named in this action. It is therefore not a rule of 
general applicability.
---------------------------------------------------------------------------

    \93\ 58 FR 51735, 51738 (October 4, 1993).
---------------------------------------------------------------------------

B. Executive Order 13771: Reducing Regulations and Controlling 
Regulatory Costs

    This action is not an Executive Order 13771 regulatory action 
because this action is not significant under Executive Order 12866.

C. Paperwork Reduction Act

    This proposed action does not impose an information collection 
burden under the provisions of the Paperwork Reduction Act (PRA).\94\ A 
``collection of information'' under the PRA means ``the obtaining, 
causing to be obtained, soliciting, or requiring the disclosure to an 
agency, third parties or the public of information by or for an agency 
by means of identical questions posed to, or identical reporting, 
recordkeeping, or disclosure requirements imposed on, ten or more 
persons, whether such collection of information is mandatory, 
voluntary, or required to obtain or retain a benefit.'' \95\ Because 
this proposed rule revises regional haze requirements reporting 
requirements for three facilities, the PRA does not apply.
---------------------------------------------------------------------------

    \94\ 44 U.S.C. 3501 et seq.
    \95\ 5 CFR 1320.3(c) (emphasis added).
---------------------------------------------------------------------------

D. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) generally requires an agency 
to prepare a regulatory flexibility analysis of any rule subject to 
notice and comment rulemaking requirements under the Administrative 
Procedure Act or any other statute unless the agency certifies that the 
rule will not have a significant economic impact on a substantial 
number of small entities. Small entities include small businesses, 
small organizations and small governmental jurisdictions.
    For purposes of assessing the impacts of this proposed rule on 
small entities, small entity is defined as: (1) A small business as 
defined by the Small Business Administration's (SBA) regulations at 13 
CFR 121.201; (2) a small governmental jurisdiction that is a government 
of a city, county, town, school district or special district with a 
population of less than 50,000; and (3) a small organization that is 
any not-for-profit enterprise which is independently owned and operated 
and is not dominant in its field.
    After considering the economic impacts of this proposed rule on 
small entities, I certify that this action will not have a significant 
economic impact on a substantial number of small entities under the 
RFA. This rule does not impose any requirements or create impacts on 
small entities as no small entities are subject to the requirements of 
this rule.

[[Page 3576]]

E. Unfunded Mandates Reform Act (UMRA)

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for federal agencies to assess the 
effects of their regulatory actions on state, local and tribal 
governments and the private sector. Under section 202 of UMRA, the EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for final rules with ``Federal mandates'' that may result in 
expenditures to state, local, and tribal governments, in the aggregate, 
or to the private sector, of $100 million or more (adjusted for 
inflation) in any one year. Before promulgating an EPA rule for which a 
written statement is needed, section 205 of UMRA generally requires the 
EPA to identify and consider a reasonable number of regulatory 
alternatives and adopt the least costly, most cost-effective, or least 
burdensome alternative that achieves the objectives of the rule. The 
provisions of section 205 of UMRA do not apply when they are 
inconsistent with applicable law. Moreover, section 205 of UMRA allows 
the EPA to adopt an alternative other than the least costly, most cost-
effective, or least burdensome alternative if the Administrator 
publishes with the final rule an explanation why that alternative was 
not adopted. Before the EPA establishes any regulatory requirements 
that may significantly or uniquely affect small governments, including 
tribal governments, it must have developed under section 203 of UMRA a 
small government agency plan. The plan must provide for notifying 
potentially affected small governments, enabling officials of affected 
small governments to have meaningful and timely input in the 
development of EPA regulatory actions with significant federal 
intergovernmental mandates, and informing, educating, and advising 
small governments on compliance with the regulatory requirements.
    Under Title II of UMRA, the EPA has determined that this proposed 
rule does not contain a federal mandate that may result in expenditures 
that exceed the inflation-adjusted UMRA threshold of $100 million \96\ 
by state, local, or tribal governments or the private sector in any one 
year. The proposed revisions to the 2014 FIP would reduce private 
sector expenditures. Additionally, we do not foresee significant costs 
(if any) for state and local governments. Thus, because the proposed 
revisions to the 2014 FIP reduce annual expenditures, this proposed 
rule is not subject to the requirements of sections 202 or 205 of UMRA. 
This proposed rule is also not subject to the requirements of section 
203 of UMRA because it contains no regulatory requirements that might 
significantly or uniquely affect small governments.
---------------------------------------------------------------------------

    \96\ Adjusted to 2019 dollars, the UMRA threshold becomes $164 
million.
---------------------------------------------------------------------------

F. Executive Order 13132: Federalism

    Executive Order 13132, Federalism,\97\ revokes and replaces 
Executive Orders 12612 (Federalism) and 12875 (Enhancing the 
Intergovernmental Partnership). Executive Order 13132 requires the EPA 
to develop an accountable process to ensure ``meaningful and timely 
input by State and local officials in the development of regulatory 
policies that have federalism implications.'' \98\ ``Policies that have 
federalism implications'' is defined in the Executive Order to include 
regulations that have ``substantial direct effects on the States, on 
the relationship between the national government and the States, or on 
the distribution of power and responsibilities among the various levels 
of government.'' \99\ Under Executive Order 13132, the EPA may not 
issue a regulation ``that has federalism implications, that imposes 
substantial direct compliance costs, . . . and that is not required by 
statute, unless [the federal government provides the] funds necessary 
to pay the direct [compliance] costs incurred by the State and local 
governments,'' or the EPA consults with state and local officials early 
in the process of developing the final regulation.\100\ The EPA also 
may not issue a regulation that has federalism implications and that 
preempts state law unless the agency consults with state and local 
officials early in the process of developing the final regulation.
---------------------------------------------------------------------------

    \97\ 64 FR 43255, 43255-43257 (August 10, 1999).
    \98\ 64 FR 43255, 43257.
    \99\ Id.
    \100\ Id.
---------------------------------------------------------------------------

    This action does not have federalism implications. The proposed FIP 
revisions will not have substantial direct effects on the states, on 
the relationship between the national government and the states, or on 
the distribution of power and responsibilities among the various levels 
of government, as specified in Executive Order 13132. Thus, Executive 
Order 13132 does not apply to this action.

G. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    Executive Order 13175, entitled ``Consultation and Coordination 
with Indian Tribal Governments,'' requires the EPA to develop an 
accountable process to ensure ``meaningful and timely input by tribal 
officials in the development of regulatory policies that have tribal 
implications.'' \101\ This proposed rule does not have tribal 
implications, as specified in Executive Order 13175. It will not have 
substantial direct effects on tribal governments. Thus, Executive Order 
13175 does not apply to this rule.
---------------------------------------------------------------------------

    \101\ 65 FR 67249, 67250 (November 9, 2000).
---------------------------------------------------------------------------

H. Executive Order 13045: Protection of Children From Environmental 
Health Risks and Safety Risks

    This action is not subject to Executive Order 13045 (62 FR 19885, 
April 23, 1997). The EPA interprets Executive Order 13045 as applying 
only to those regulatory actions that concern environmental health or 
safety risks that the EPA has reason to believe may disproportionately 
affect children, per the definition of ``covered regulatory action'' in 
section 2-202 of the executive order. This action is not subject to 
Executive Order 13045 because it does not concern an environmental 
health risk or safety risk.

I. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use

    This action is not subject to Executive Order 13211 (66 FR 28355 
(May 22, 2001)), because it is not a significant regulatory action 
under Executive Order 12866.

J. National Technology Transfer and Advancement Act

    Section 12 of the National Technology Transfer and Advancement Act 
(NTTAA) of 1995 requires federal agencies to evaluate existing 
technical standards when developing a new regulation. Section 12(d) of 
NTTAA, Public Law 104-113, 12(d) (15 U.S.C. 272 note) directs the EPA 
to consider and use ``voluntary consensus standards'' in its regulatory 
activities unless to do so would be inconsistent with applicable law or 
otherwise impractical. Voluntary consensus standards are technical 
standards (e.g., materials specifications, test methods, sampling 
procedures and business practices) that are developed or adopted by 
voluntary consensus standards bodies. NTTAA directs the EPA to

[[Page 3577]]

provide Congress, through OMB, explanations when the agency decides not 
to use available and applicable voluntary consensus standards.
    This proposed rulemaking does not involve technical standards. 
Therefore, EPA is not considering the use of any voluntary consensus 
standards.

K. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations

    Executive Order 12898, establishes federal executive policy on 
environmental justice.\102\ Its main provision directs federal 
agencies, to the greatest extent practicable and permitted by law, to 
make environmental justice part of their mission by identifying and 
addressing, as appropriate, disproportionately high and adverse human 
health or environmental effects of their programs, policies and 
activities on minority populations and low-income populations in the 
United States.
---------------------------------------------------------------------------

    \102\ 59 FR 7629 (February 16, 1994).
---------------------------------------------------------------------------

    I certify that the approaches under this proposed rule will not 
have potential disproportionately high and adverse human health or 
environmental effects on minority, low-income or indigenous/tribal 
populations. As explained previously, the Utah Regional Haze SIP, as 
revised by this action, will ensure a significant reduction in 
emissions compared to regional haze baseline levels (2002). In 
addition, the area where the Hunter, Huntington, and Carbon power 
plants are located has not been designated nonattainment for any NAAQS. 
The proposed SIP revisions will not create a disproportionately high 
and adverse human health or environmental effect on minority, low-
income, or indigenous/tribal populations. The EPA, however, will 
consider any input received during the public comment period regarding 
environmental justice considerations.

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Nitrogen dioxide, Particulate 
matter, Sulfur oxides.

    Dated: January 9, 2020.
Gregory Sopkin,
Regional Administrator, Region 8.
    For the reasons set forth in the preamble, 40 CFR part 52 is 
proposed to be amended as follows:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

0
1. The authority citation for part 52 continues to read as follows:

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

Subpart TT--Utah

0
2. Section 52.2320 paragraph (c) is amended as follows:
0
a. Under the heading ``R307-110. General Requirements: State 
Implementation Plan,'' revise the table entry ``R307-110-17.''
0
b. Under the heading ``R307-110. General Requirements: State 
Implementation Plan,'' add, in numerical order, the table entry ``R307-
110-28.''
0
c. Under the heading ``R307-150. Emission Inventories,'' revise the 
table entry ``R307-150-3.''
    The amendments read as follows:

Sec.  52.2320  Identification of plan.

* * * * *
    (c) * * *

----------------------------------------------------------------------------------------------------------------
                                                           State
           Rule No.                  Rule title          effective    Final rule citation,        Comments
                                                           date               date
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------
                            R307-110. General Requirements: State Implementation Plan
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
R307-110-17...................  Section IX. Control       11/25/2019  [Insert Federal       ....................
                                 Measures for Area                     Register citation]
                                 and Point Sources,                    1/22/2020.
                                 Part H, Emission
                                 Limits.
 
                                                  * * * * * * *
R307-110-28...................  Section XX. Regional       8/15/2019  [Insert Federal       ....................
                                 Haze.                                 Register citation]
                                                                       1/22/2020.
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------
                                         R307-150. Emission Inventories
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
R307-150-3....................  Applicability.......       6/25/2019  [Insert Federal       ....................
                                                                       Register citation]
                                                                       1/22/2020.
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

0
3. In Sec.  52.2320 amend paragraph (e) by:
0
a. Under the heading ``IX. Control Measures for Area and Point 
Sources,'' adding, in numerical order, table entries ``IX.H.21. General 
Requirements: Control Measures for Area and Point Sources, Emission 
Limits and Operating Practices, Regional Haze Requirements,'' and 
``IX.H.22. Source Specific Emission Limitations: Regional Haze 
Requirements, Best Available Retrofit Technology.''
0
b. Under the heading ``XVII. Visibility Protection,'' removing the 
table entries ``Section XX.D.6. Best Available Retrofit Technology 
(BART) Assessment for

[[Page 3578]]

NOX and PM,'' and ``Section XX.G. Long-Term Strategy for 
Fire Programs.''
0
c. Adding a centered heading ``XX. Regional Haze'' after the table 
entry ``Section XXIII. Interstate Transport.''
0
d. Under the heading ``XX. Regional Haze'' adding the table entries 
``Section XX.A. Executive Summary,'' ``Section XX.B. Background on the 
Regional Haze Rule,'' ``Section XX.C. Long-Term Strategy for the Clean-
Air Corridor,'' ``Section XX.D. Long-Term Strategy for Stationary 
Sources,'' ``Section XX.E. Sulfur Dioxide Milestones and Backstop 
Trading Program,'' ``Section XX.F. Long-Term Strategy for Mobile 
Sources,'' ``Section XX.G. Long-Term Strategy for Fire Programs,'' 
``Section XX.H. Assessment of Emissions from Paved and Unpaved Road 
Dust,'' ``Section XX.I. Pollution Prevention and Renewable Energy 
Programs,'' ``Section XX.J. Other GCVTC Recommendations,'' ``Section 
XX.K. Projection of Visibility Improvement Anticipated from Long-Term 
Strategy,'' ``Section XX.L. Periodic Implementation Plan Revisions,'' 
``Section XX.M. State Planning/Interstate Coordination and Tribal 
Implementation,'' and ``Section XX.N. Enforceable Commitments for the 
Utah Regional Haze SIP.''
    The revisions and additions read as follows:

Sec.  52.2320  Identification of plan.

* * * * *
    (e) * * *

----------------------------------------------------------------------------------------------------------------
                                               State
               Rule title                    effective     Final rule citation, date           Comments
                                               date
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------
                                 IX. Control Measures for Area and Point Sources
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
IX.H.21. General Requirements: Control        11/25/2019  [Insert Federal Register    ..........................
 Measures for Area and Point Sources,                      citation] 1/22/2020.
 Emission Limits and Operating
 Practices, Regional Haze Requirements.
IX.H.22. Source Specific Emission             11/25/2019  [Insert Federal Register    ..........................
 Limitations: Regional Haze                                citation] 1/22/2020.
 Requirements, Best Available Retrofit
 Technology.
 
                                                  * * * * * * *
Section XXIII. Interstate Transport.....        2/9/2007  73 FR 16543, 3/28/2008....  ..........................
----------------------------------------------------------------------------------------------------------------
                                                XX. Regional Haze
----------------------------------------------------------------------------------------------------------------
Section XX.A. Executive Summary.........       8/15/2019  [Insert Federal Register    ..........................
                                                           citation] 1/22/2020.
Section XX.B. Background on the Regional       8/15/2019  [Insert Federal Register    ..........................
 Haze Rule.                                                citation].
                                                          1/22/2020.................
Section XX.C. Long-Term Strategy for the       8/15/2019  [Insert Federal Register    ..........................
 Clean-Air Corridor.                                       citation] 1/22/2020.
Section XX.D. Long-Term Strategy for           8/15/2019  [Insert Federal Register    ..........................
 Stationary Sources.                                       citation] 1/22/2020.
Section XX.E. Sulfur Dioxide Milestones        8/15/2019  [Insert Federal Register    ..........................
 and Backstop Trading Program.                             citation] 1/22/2020.
Section XX.F. Long-Term Strategy for           8/15/2019  [Insert Federal Register    ..........................
 Mobile Sources.                                           citation] 1/22/2020.
Section XX.G. Long-Term Strategy for            4/7/2011  78 FR 4071, 1/18/2013.....  ..........................
 Fire Programs.
Section XX.H. Assessment of Emissions          8/15/2019  [Insert Federal Register    ..........................
 from Paved and Unpaved Road Dust.                         citation] 1/22/2020.
Section XX.I. Pollution Prevention and         8/15/2019  [Insert Federal Register    ..........................
 Renewable Energy Programs.                                citation] 1/22/2020.
Section XX.J. Other GCVTC                      8/15/2019  [Insert Federal Register    ..........................
 Recommendations.                                          citation] 1/22/2020.
Section XX.K. Projection of Visibility         8/15/2019  [Insert Federal Register    ..........................
 Improvement Anticipated from Long-Term                    citation] 1/22/2020.
 Strategy.
Section XX.L. Periodic Implementation          8/15/2019  [Insert Federal Register    ..........................
 Plan Revisions.                                           citation] 1/22/2020.
Section XX.M. State Planning/Interstate        8/15/2019  [Insert Federal Register    ..........................
 Coordination and Tribal Implementation.                   citation] 1/22/2020.
Section XX.N. Enforceable Commitments          8/15/2019  [Insert Federal Register    ..........................
 for the Utah Regional Haze SIP.                           citation] 1/22/2020.
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

Sec.  52.2336  [Removed]

0
4. Remove Sec.  52.2336.

[FR Doc. 2020-00495 Filed 1-21-20; 8:45 am]
 BILLING CODE 6560-50-P