Document ID: EPA-R09-OAR-2018-0761-0001
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: Arizona; Regional Haze Progress Report
Posted Date: 2019-03-27T04:00Z

[Federal Register Volume 84, Number 59 (Wednesday, March 27, 2019)]
[Proposed Rules]
[Pages 11455-11464]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-05769]

=======================================================================
-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2018-0761; FRL-9991-30-Region 9]

Air Plan Approval; Arizona; Regional Haze Progress Report

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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

SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve Arizona's Regional Haze Progress Report (``Progress Report'' or 
``Report''), submitted by the State of Arizona on November 12, 2015, as 
a revision to its state implementation plan (SIP). Arizona submitted 
its Progress Report and a negative declaration stating that further 
revision of the existing regional haze implementation plan is not 
needed at this time. The Progress Report addresses the federal Regional 
Haze Rule requirements under the Clean Air Act (CAA) to submit a report 
describing progress in achieving reasonable progress goals (RPGs) 
established for regional haze and a determination of the adequacy of 
the state's existing implementation plan addressing regional haze. 
Arizona's Progress Report notes that Arizona has implemented the 
measures in the regional haze implementation plan due to be in place by 
the date of the Progress Report and that visibility in Class I areas 
affected by emissions from Arizona is improving. The EPA is proposing 
approval of Arizona's determination that the State's regional haze 
implementation plan is adequate to meet RPGs in Class I areas affected 
by emissions from Arizona for the first implementation period, which 
extended through 2018, and requires no substantive revision at this 
time.

DATES: Comments must be received on or before April 26, 2019.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R09-
OAR-2018-0761 at https://www.regulations.gov. Follow the online 
instructions for submitting comments. Once submitted, comments cannot 
be edited or removed from Regulations.gov. The EPA may publish any 
comment received to its public docket. Do not submit 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 https://www2.epa.gov/dockets/commenting-epa-dockets.

[[Page 11456]]

FOR FURTHER INFORMATION CONTACT: Panah Stauffer, EPA Region IX, (415) 
972-3247, stauffer.panah@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document whenever ``we,'' 
``us,'' or ``our'' is used, it is intended to refer to the EPA.

Table of Contents

I. Background
    A. Description of Regional Haze
    B. History of Regional Haze Rule
    C. Arizona's Regional Haze Plan
II. Context for Understanding Arizona's Progress Report
    A. Framework for Measuring Progress
    B. Data Sources for Arizona's Progress Report
III. The EPA's Review of Arizona's Progress Report
    A. Status of Implementation of All Measures Included in the 
Regional Haze Implementation Plan
    B. Summary of Emissions Reductions
    C. Summary of Visibility Conditions
    D. Determination of Adequacy
    E. Consultation With Federal Land Managers (FLMs)
IV. The EPA's Proposed Action
V. Statutory and Executive Order Reviews

I. Background

A. Description of Regional Haze

    Fine particles impair visibility by scattering and absorbing light, 
thereby reducing the clarity, color, and visible distance that one can 
see. Regional haze is visibility impairment produced by emissions of 
fine particles by numerous sources and activities located across a 
broad geographic area. These fine particles can also cause serious 
health effects and mortality in humans and contribute to environmental 
impacts, such as acid deposition and eutrophication of water bodies.

B. History of Regional Haze Rule

    In section 169A(a)(1) of the CAA Amendments of 1977, Congress 
created a program to protect visibility in designated national parks 
and wilderness areas, establishing 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.'' In accordance with section 169A of the 
CAA and after consulting with the Department of the Interior, the EPA 
promulgated a list of 156 mandatory Class I federal areas where 
visibility is identified as an important value.\1\ In this notice, we 
refer to mandatory Class I federal areas on this list as ``Class I 
areas.''
---------------------------------------------------------------------------

    \1\ The Class I areas are listed at 40 CFR part 81, subpart D. 
Areas designated as Class I areas consist of national parks 
exceeding 6,000 acres, wilderness areas and national memorial parks 
exceeding 5,000 acres, and all international parks that were in 
existence on August 7, 1977 (42 U.S.C. 7472(a)).
---------------------------------------------------------------------------

    With the CAA Amendments of 1990, Congress added section 169B to 
address regional haze issues. The EPA promulgated the Regional Haze 
Rule (RHR) on July 1, 1999.\2\ In the RHR, the EPA revised the existing 
visibility regulations to integrate provisions addressing regional haze 
impairment and to establish a comprehensive visibility protection 
program for Class I areas. As defined in the RHR, the RPGs must provide 
for an improvement in visibility for the most impaired days (``worst 
days'') over the period of the implementation plan and ensure no 
degradation in visibility for the least impaired days (``best days'') 
over the same period.\3\ The first regional haze implementation plan 
generally covers the period from 2000-2018 (also known as the first 
planning period).
---------------------------------------------------------------------------

    \2\ 64 FR 35714 (July 1, 1999). The rule was subsequently 
revised on July 6, 2005 (70 FR 39103), October 13, 2006 (71 FR 
60611), and January 10, 2017 (82 FR 3078).
    \3\ 40 CFR 51.308(d)(1).
---------------------------------------------------------------------------

    Five years after submittal of the initial regional haze plan, 
states were required to submit progress reports that evaluate progress 
towards the RPGs for each Class I area within the state and in each 
Class I area outside the state that may be affected by emissions from 
within the state.\4\ States were also required to submit, at the same 
time as the progress report, a determination of the adequacy of the 
state's existing regional haze plan.\5\
---------------------------------------------------------------------------

    \4\ 40 CFR 51.308(g).
    \5\ 40 CFR 51.308(h).
---------------------------------------------------------------------------

C. Arizona's Regional Haze Plan

    Arizona submitted its initial regional haze SIP under 40 CFR 51.308 
to the EPA on February 28, 2011 (hereinafter ``2011 Submittal'').\6\ 
The EPA actions in Table 1 followed the 2011 Submittal.
---------------------------------------------------------------------------

    \6\ On December 23, 2003, the Arizona Department of 
Environmental Quality (ADEQ) submitted a Regional Haze plan under 40 
CFR 51.309 (``309 Plan''). Letter dated December 23, 2003, from 
Stephen A. Owens, Director, ADEQ, to Wayne Nastri, Regional 
Administrator, EPA, Region IX. On December 30, 2004, ADEQ submitted 
a revision to its 309 Plan, consisting of rules on emissions trading 
and smoke management, and a correction to the State's regional haze 
statutes. Letter dated December 30, 2004, from Stephen A. Owens, 
Director, ADEQ, to Wayne Nastri, Regional Administrator, EPA. On 
December 24, 2008, ADEQ sent a letter resubmitting the 309 Plan 
revisions to the EPA. Letter dated December 24, 2008, from Stephen 
A. Owens, Director, ADEQ, to Wayne Nastri, Regional Administrator, 
EPA. On May 16, 2006 (71 FR 28270) and May 8, 2007 (72 FR 25973), 
the EPA approved the smoke management rules that were part of these 
submittals. On August 8, 2013 (78 FR 48326), the EPA disapproved the 
remainder of the State's submittals under 40 CFR 309. Therefore, 
these prior submittals are not relevant for purposes of the Progress 
Report, unless otherwise noted.

Table 1--Arizona Regional Haze--Summary of EPA Actions Under CAA Section
                                   308
------------------------------------------------------------------------
                 Date                              EPA action
------------------------------------------------------------------------
December 5, 2012.....................  ``Phase 1'' partial approval and
                                        partial disapproval of certain
                                        provisions of the 2011 Submittal
                                        and promulgation of partial
                                        federal implementation plan
                                        (FIP).\a\
July 30, 2013........................  ``Phase 2'' partial approval and
                                        partial disapproval of remaining
                                        portions of Arizona Regional
                                        Haze 2011 Submittal.\b\
September 3, 2014....................  ``Phase 3'' promulgation of FIP
                                        for remaining portions of
                                        Arizona Regional Haze
                                        program.\c\
April 10, 2015.......................  Approval of SIP revision for the
                                        Arizona Electric Power
                                        Cooperative (AEPCO) Apache
                                        Generating Station.\d\
April 17, 2015.......................  FIP revision replacing the
                                        control technology demonstration
                                        requirements for nitrogen oxides
                                        (NOX) at Lhoist North America of
                                        Arizona, Inc. Nelson Lime Plant
                                        with revised recordkeeping and
                                        reporting requirements.\e\
April 13, 2016.......................  FIP revision revising NOX
                                        requirements for the Salt River
                                        Project Agricultural Improvement
                                        and Power District (SRP)
                                        Coronado Generating Station.\f\
November 21, 2016....................  FIP revision replacing the
                                        control technology demonstration
                                        requirements for NOX at
                                        CalPortland Cement (CPC) Rillito
                                        Plant Kiln 4 and Phoenix Cement
                                        Company (PCC) Clarkdale Plant
                                        Kiln 4 with revised
                                        recordkeeping and reporting
                                        requirements.\g\
March 27, 2017.......................  Approval of SIP revision to
                                        replace FIP for Arizona Public
                                        Service (APS) Cholla Generating
                                        Station.\h\
October 10, 2017.....................  Approval of SIP revision to
                                        replace FIP for the SRP Coronado
                                        Generating Station.\i\
------------------------------------------------------------------------
\a\ 77 FR 72511 (December 5, 2012).
\b\ 78 FR 461421 (July 30, 2013).
\c\ 79 FR 52419 (September 3, 2014).
\d\ 80 FR 19220 (April 10, 2015).
\e\ 80 FR 21176 (April 17, 2015).
\f\ 81 FR 21735 (April 13, 2016).
\g\ 81 FR 83144 (November 21, 2016).
\h\ 82 FR 15139 (March 27, 2017).
\i\ 82 FR 46903 (October 10, 2017).

[[Page 11457]]

    On November 12, 2015, the State of Arizona submitted its Progress 
Report to meet the requirements of 40 CFR 51.308(g) and (h).\7\ In 
accordance with these requirements, the Progress Report describes the 
status of implementation of measures included in the regional haze 
implementation plan, emissions reductions from these measures, and 
improvements in visibility conditions at the State's Class I areas. The 
Progress Report also includes a negative declaration stating that 
further revision of the existing implementation plan is not needed in 
accordance with 40 CFR 51.308(h)(1).
---------------------------------------------------------------------------

    \7\ Letter dated November 12, 2015, from Eric C. Massey, 
Director, Air Quality Division, ADEQ, to Jared Blumenfeld, Regional 
Administrator, EPA Region IX.
---------------------------------------------------------------------------

II. Context for Understanding Arizona's Progress Report

    To facilitate a better understanding of Arizona's Progress Report 
as well as the EPA's evaluation of it, this section provides background 
on the regional haze program in Arizona.

A. Framework for Measuring Progress

    The EPA has established a metric for determining visibility 
conditions at Class I areas referred to as the ``deciview index,'' 
which is measured in deciviews, as defined in 40 CFR 51.301. A deciview 
expresses uniform changes in haziness in terms of common increments 
across the entire range of visibility conditions (i.e., pristine (low 
deciview) to extremely hazy (high deciview)). Deciviews are determined 
by using air quality data collected from the Interagency Monitoring of 
Protected Visual Environments (IMPROVE) network monitors to estimate 
light extinction, and then transforming the value of light extinction 
using a logarithmic function. Arizona has 12 Class I areas within its 
borders: The Chiricahua National Monument, Chiricahua Wilderness Area, 
Galiuro Wilderness Area, Grand Canyon National Park, Mazatzal 
Wilderness Area, Mount Baldy Wilderness Area, Petrified Forest National 
Park, Pine Mountain Wilderness, Saguaro National Park, Sierra Ancha 
Wilderness Area, Superstition Wilderness Area, and Sycamore Canyon 
Wilderness Area. For this Progress Report, monitoring data representing 
visibility conditions in Arizona's 12 Class I areas were based on the 
ten IMPROVE monitors identified in Table 2.

 Table 2--Arizona IMPROVE Monitoring Sites and Represented Class I Areas
------------------------------------------------------------------------
             Site code                          Class I area
------------------------------------------------------------------------
BALD1.............................  Mount Baldy Wilderness.
CHIR1.............................  Chiricahua National Monument,
                                     Chiricahua Wilderness & Galiuro
                                     Wilderness.
GRCA2.............................  Grand Canyon National Park.
IKBA1.............................  Mazatzal Wilderness & Pine Mountain
                                     Wilderness.
PEFO1.............................  Petrified Forest National Park.
SAGU1.............................  Saguaro National Monument--East
                                     Unit.
SAWE1.............................  Saguaro National Monument--West
                                     Unit.
SIAN1.............................  Sierra Ancha Wilderness.
SYCA2.............................  Sycamore Canyon Wilderness.
TONT1.............................  Superstition Wilderness.
------------------------------------------------------------------------
Source: 2015 Arizona Regional Haze 5-Year Progress Report, Table 17, 25.

    Under the RHR, a state's initial regional haze plan must establish 
two RPGs for each of its Class I areas: One for the 20 percent least 
impaired days and one for the 20 percent most impaired days. The RPGs 
must provide for an improvement in visibility on the 20 percent most 
impaired days and ensure no degradation in visibility on the 20 percent 
least impaired days, as compared to visibility conditions during the 
baseline period. In establishing the RPGs, a state must consider the 
uniform rate of visibility improvement from the baseline to natural 
conditions in 2064 and the emission reduction measures needed to 
achieve that uniform rate. The EPA's 2014 FIP set the RPGs for 
Arizona's 12 Class I areas based on modeling performed by the Western 
Regional Air Partnership (WRAP), scaled according to projected emission 
reductions from the FIP's controls for best available retrofit 
technology (BART) and reasonable progress. Arizona used these RPGs in 
its Progress Report.\8\
---------------------------------------------------------------------------

    \8\ The RPGs are shown in Table 10 of today's action.
---------------------------------------------------------------------------

    In addition, the Progress Report addresses Arizona's potential 
contribution to visibility impairment at twelve Class 1 areas located 
in three other states: Colorado, Utah, and New Mexico.

B. Data Sources for Arizona's Progress Report

    To demonstrate visibility progress, the Arizona Department of 
Environmental Quality (ADEQ) used recent visibility information 
available from the WRAP Technical Support System (TSS). It also used 
the technical data and analyses in the ``Western Regional Air 
Partnership Regional Haze Rule Reasonable Progress Summary Report'' 
(``WRAP Report''), dated June 28, 2013.\9\ The WRAP Report was prepared 
for WRAP ``on behalf of the 15 western state members in the WRAP 
region, to provide the technical basis for the first of RHR individual 
progress reports.'' \10\ ADEQ's Progress Report presented data for each 
of its Class I areas comparing visibility conditions for the 20 percent 
most impaired and 20 percent least impaired days during the baseline 
period (2000-2004), the current period for the Progress Report (2009-
2013), and years between those periods. ADEQ also relied on WRAP TSS 
data for its emissions inventory.
---------------------------------------------------------------------------

    \9\ 2015 Arizona Regional Haze 5-Year Progress Report, 2.
    \10\ The WRAP Report is available at http://www.wrapair2.org/documents/Full%20Report/WRAP_RHRPR_Full_Report_without_Appendices.PDF.
---------------------------------------------------------------------------

    The emissions data for BART sources and non-BART electrical 
generating units (EGUs) came from information the facilities report to 
the EPA's Clean Air Markets Division (CAMD) database. Emissions data 
for non-electric generating unit (non-EGU) sources came from the 2008 
and 2011 National Emissions Inventory as well as ADEQ's internal point 
source emission database. ADEQ also calculated emissions averted from 
prescribed burning of nonagricultural fuels using WRAP-recommended 
emission reduction techniques.

III. The EPA's Review of Arizona's Progress Report

    This section describes the contents of Arizona's Progress Report, 
the EPA's review of the report, the determination of adequacy required 
by 40 CFR 51.308(h), and the requirement for state and federal land 
manager coordination in 40 CFR 51.308(i).

A. Status of Implementation of All Measures Included in the Regional 
Haze Implementation Plan

    In its Progress Report, Arizona provided descriptions and 
compliance dates for emissions limits on the seven BART sources 
established through the Arizona Regional Haze SIP \11\ and the Arizona 
Regional Haze FIP.\12\ The Progress Report also described controls and 
compliance dates for two reasonable progress sources that the EPA 
established in the Arizona Regional

[[Page 11458]]

Haze FIP.\13\ The Progress Report addressed the status of these sources 
at the time of the Report's submittal in 2015. However, most of the 
compliance dates for these sources had not yet passed at the time of 
the Report's submittal, so information regarding compliance was not 
available. Following submittal of the Progress Report, the EPA has 
taken several actions to approve revisions to the Arizona Regional Haze 
SIP and to revise the Arizona Regional Haze FIP, as shown in Table 1 
above. These revisions superseded some of the SIP requirements 
discussed in the Progress Report. The RHR requires a progress report to 
address the ``implementation plan,'' defined in 40 CFR 51.301 as any 
SIP, FIP, or tribal implementation plan.\14\ Accordingly, in the 
following sections, we summarize the currently applicable requirements 
of the Arizona Regional Haze SIP and Arizona Regional Haze FIP, as 
described in the Progress Report and revised by subsequent SIP and FIP 
actions.
---------------------------------------------------------------------------

    \11\ We refer to the approved provisions of the Arizona Regional 
Haze Plan (including approved revisions) collectively as the 
``Arizona Regional Haze SIP.''
    \12\ We refer to the various FIP requirements promulgated by the 
EPA collectively as the ``Arizona Regional Haze FIP.''
    \13\ These sources were not subject to BART, but the EPA 
determined that they were required to implement controls under the 
reasonable progress requirements of the RHR.
    \14\ No tribe in Arizona has a tribal implementation plan for 
regional haze.
---------------------------------------------------------------------------

    As described further below, beyond stationary source controls 
required in the SIP and FIP, ADEQ also included visibility progress 
made from the closure of certain stationary sources, existing federal 
and state regulations, and the State's Enhanced Smoke Management 
Program.\15\
---------------------------------------------------------------------------

    \15\ 2015 Arizona Regional Haze 5-Year Progress Report, 13-18.
---------------------------------------------------------------------------

1. Subject-to-BART Sources
    Under the RHR, states are directed to conduct BART determinations 
for BART-eligible \16\ sources that may be anticipated to cause or 
contribute to any visibility impairment in a Class I area (known as 
``subject-to-BART'' sources).\17\ States also have the flexibility to 
adopt alternatives that provide greater reasonable progress towards 
natural visibility conditions than BART for one or more subject-to-BART 
sources (commonly known as ``better-than-BART'' alternatives).\18\ The 
Arizona Regional Haze SIP and Arizona Regional Haze FIP identified 
seven subject-to-BART facilities (i.e., facilities that include one or 
more BART-eligible units and were determined to be subject to BART): 
AEPCO Apache Generating Station; APS Cholla Generating Station; SRP 
Coronado Generating Station; Freeport-McMoRan Miami, Inc. Miami 
Smelter; ASARCO, Inc., (``Asarco'') Hayden Smelter; Tucson Electric 
Power (TEP) Sundt Generating Station; and the Nelson Lime Plant. The 
Arizona Regional Haze SIP and Arizona Regional Haze FIP establish BART 
or better-than-BART alternative controls for NOX, 
particulate matter (PM), and sulfur dioxide (SO2) for each 
of these sources.
---------------------------------------------------------------------------

    \16\ A BART-eligible source is an existing stationary source in 
any of 26 listed categories built between 1962 and 1977 with 
potential emissions of at least 250 tons per year. 40 CFR 51.301 and 
40 CFR part 51 appendix Y, section II.
    \17\ 40 CFR 51.308(e).
    \18\ 40 CFR 51.308(e)(2).
---------------------------------------------------------------------------

a. Apache Generating Station
    The Apache Generating Station (``Apache'') has three BART-eligible 
units: ST1, ST2, and ST3. Unit ST1 is a wall-fired boiler with a net 
unit output of 85 megawatts (MW) that burns pipeline-quality natural 
gas as its primary fuel and can operate alone or in combined-cycle mode 
with an adjacent Gas Turbine (GT1). Units ST2 and ST3 are both dry-
bottom, Riley Stoker turbo-fired boilers, operating on sub-bituminous 
coal, each with a gross unit output of 204 MW.
    On December 5, 2012, the EPA approved the State's SO2 
and PM BART limits for Apache and established FIP NOX 
emission limits for units ST2 and ST3 based on installation and 
operation of selective catalytic reduction (SCR). On April 10, 2015, 
the EPA approved a SIP revision for Apache (``Apache SIP Revision'') 
that included a better-than-BART alternative for Apache units ST2 and 
ST3 (``Apache BART Alternative'') and a revised NOX emission 
limit for ST1 that applies when it operates in combined-cycle mode with 
the adjacent GT1.\19\ Under the Apache BART Alternative, ST2 was 
converted from a primarily coal-fired unit to a unit that combusts 
pipeline-quality natural gas, while ST3 remains as a coal-fired unit 
and has been retrofitted with selective non-catalytic reduction (SNCR). 
The emission limits associated with the Apache BART Alternative are 
summarized in Table 3. The compliance date for all limits was December 
5, 2017, except that a more stringent limit for PM10 of 
0.008 pounds per million British thermal units (lb/MMBtu) at ST2 that 
became effective on December 5, 2018.
---------------------------------------------------------------------------

    \19\ 80 FR 19220 (April 10, 2015).

                              Table 3--Emission Limits for Apache BART Alternative
----------------------------------------------------------------------------------------------------------------
                                              Emission Limit (lb/MMbtu, averaged over 30 boiler operating days)
                    Unit                    --------------------------------------------------------------------
                                                   NOX                       PM10                       SO2
----------------------------------------------------------------------------------------------------------------
ST2........................................           0.085  0.01, then 0.008 (effective                 0.00064
                                                              December 5, 2018).
ST3........................................            0.23  0.03...............................            0.15
----------------------------------------------------------------------------------------------------------------

    The Apache SIP Revision also included a revised NOX 
emission limit for the combined-cycle operation of ST1 with GT1 from 
0.056 lb/MMBtu to 0.10 lb/MMBtu and set a 1,205 lb/day NOX 
limit, based on a 30-calendar-day average, for ST1 operating in stand-
alone mode or in combined-cycle mode with GT1. Finally, the Apache SIP 
Revision incorporated monitoring, recordkeeping, and reporting 
requirements for the existing ST1 BART SIP limits of 0.00064 lb 
SO2/MMBtu and 0.0075 lb PM10/MMBtu into the SIP. 
Upon approval of the Apache SIP Revision, the EPA withdrew all Regional 
Haze FIP requirements that addressed BART for Apache.\20\
---------------------------------------------------------------------------

    \20\ Id.
---------------------------------------------------------------------------

b. Cholla Generating Station
    Cholla Generating Station (``Cholla'') consists of four coal-fired 
electric generating units with a total plant-wide generating capacity 
of 1150 MW. Unit 1 is a 126 MW boiler that is not BART-eligible. Unit 2 
(272 MW), Unit 3 (272 MW), and Unit 4 (410 MW) are tangentially-fired 
dry bottom boilers that are BART-eligible. On December 5, 2012, the EPA 
approved the State's SO2 and PM BART limits for Cholla and 
established FIP NOX emission limits for all three units 
based on installation and operation of SCR.
    On March 27, 2017, the EPA approved a SIP revision for Cholla 
(``Cholla SIP

[[Page 11459]]

Revision'') that included a revised BART analysis and determination for 
NOX and a revision to Cholla's operating permit to implement 
both the revised BART determination for NOX and ADEQ's prior 
BART determinations for SO2 and PM10 at 
Cholla.\21\ Under the revised NOX BART determination:
---------------------------------------------------------------------------

    \21\ 82 FR 15139 (March 27, 2017).
---------------------------------------------------------------------------

     Unit 2 was permanently shut down by April 1, 2016.
     Unit 3 and Unit 4 continue to operate with currently 
installed low-NOX burners and separated over fire air. By 
April 30, 2025, the owners will permanently cease burning coal at both 
units with the option to convert to pipeline-quality natural gas by 
July 31, 2025, with an annual average capacity factor of 20 percent or 
less.
    Upon approval of the Cholla SIP Revision, the EPA withdrew all 
Regional Haze FIP requirements applicable to Cholla.\22\ The current 
SIP-approved BART limits for Cholla are shown in Table 4.
---------------------------------------------------------------------------

    \22\ Id.

                                      Table 4--Cholla BART Emission Limits
----------------------------------------------------------------------------------------------------------------
                                                                    Emission limit (lb/MMbtu, averaged over 30
                                                                              boiler operating days)
             Unit                             Dates              -----------------------------------------------
                                                                        NOX            PM10             SO2
----------------------------------------------------------------------------------------------------------------
Unit 2........................  Unit shut down on April 1, 2016.
Unit 3........................  until April 30, 2025............            0.22           0.015            0.15
                                after April 30, 2025............            0.08            0.01          0.0006
Unit 4........................  until April 30, 2025............            0.22           0.015            0.15
                                after April 30, 2025............            0.08            0.01          0.0006
----------------------------------------------------------------------------------------------------------------

c. Coronado Generating Station
    Coronado Generating Station (``Coronado'') consists of two BART-
eligible 456 MW coal-fired steam boilers, known as Units 1 and 2. On 
December 5, 2012, the EPA approved the State's SO2 and PM 
BART limits for Coronado and established FIP NOX emission 
limits for both units based on installation and operation of SCR.
    On October 10, 2017, the EPA approved a SIP revision that included 
a better-than-BART alternative for Coronado (``Coronado SIP 
Revision''), consisting of an interim operating strategy (``Interim 
Strategy''), which is in effect from December 5, 2017, to December 31, 
2025, and a final operating strategy (``Final Strategy''), which will 
take effect on January 1, 2026.\23\ The requirements associated with 
the Interim and Final Strategies are shown in Table 5 and summarized 
briefly below.
---------------------------------------------------------------------------

    \23\ 82 FR 46903.
---------------------------------------------------------------------------

    The Interim Strategy includes three different operating options 
(designated IS2, IS3, and IS4), each of which requires a period of 
seasonal curtailment (i.e., temporary closure) for Unit 1. Each year, 
SRP must select and implement one of the three options, based on the 
NOX emissions performance of Unit 1 and the SO2 
emissions performance of Units 1 and 2 in that year. In particular, by 
October 21 of each year, SRP must notify ADEQ and the EPA of its chosen 
option for that calendar year (and for January of the following year) 
and demonstrate that its NOX and SO2 emissions 
for that year (up to the date of the notification) have not already 
exceeded the limits associated with that option. SRP then must comply 
with those limits for the remainder of the year (and for January of the 
following year) and curtail operation of Unit 1 for the time period 
required under that option. In addition, under each option, the 
facility must comply with an annual plant-wide SO2 emissions 
cap of 1,970 tons per year (tpy) effective in each year, beginning in 
2018.
    The Final Strategy in the Coronado SIP Revision requires 
installation of SCR on Unit 1 or the permanent cessation of operation 
of Unit 1 no later than December 31, 2025. SRP is required to notify 
ADEQ and the EPA of its selection by December 31, 2022. The Final 
Strategy includes two additional features: An SO2 emission 
limit of 0.060 lb/MMBtu, calculated on a 30-boiler operating day (BOD) 
rolling average and applicable to Unit 2 (as well as Unit 1 if it 
continues operating), and an annual plant-wide SO2 emissions 
cap of either 1,970 tpy if both units continue operating or 1,080 tpy 
if Unit 1 shuts down.

                                                      Table 5--Summary of Coronado BART Alternative
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Unit 1 (lb/MMBtu with 30-BOD    Unit 2 (lb/MMBtu with 30-BOD
                                                       average)                        average)              Annual plant-
             Control strategy              ----------------------------------------------------------------  wide SO2 cap     Unit 1 curtailment period
                                                  NOX             SO2             NOX             SO2            (tpy)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Interim Strategy:
    IS2...................................           0.320           0.060           0.080           0.060           1,970  October 21-January 31
    IS3...................................           0.320           0.050           0.080           0.050           1,970  November 21-January 20
    IS4...................................           0.310           0.060           0.080           0.060           1,970  November 21-January 20
--------------------------------------------------------------------------------------------------------------------------------------------------------
    Interim Strategy Timeline.............                                   Notification date: October 21 of each year.
                                                                           Operates December 5, 2017 to December 31, 2025.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Final Strategy:
    SCR Installation......................           0.065           0.060           0.080           0.060           1,970  N/A.
    Shutdown..............................             N/A             N/A           0.080           0.060           1,080  N/A.
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 11460]]

 
Final Strategy Timeline...................                                      Notification date: December 31, 2022.
                                                                        Shutdown or install & operate SCR: December 31, 2025.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The Coronado SIP revision also included PM10 limits of 
0.030 lb/MMBtu for each unit, as well as compliance deadlines and 
monitoring, recordkeeping, and reporting requirements for 
NOX, PM and SO2. Upon approval of the Coronado 
SIP revision, the EPA withdrew all Regional Haze FIP requirements 
applicable to Coronado.\24\
---------------------------------------------------------------------------

    \24\ Id.
---------------------------------------------------------------------------

d. Miami Smelter
    The Arizona Regional Haze SIP and Arizona Regional Haze FIP include 
BART requirements for Converters 2 through 5 and the electric furnace 
at the Miami Smelter. For SO2 from the converters, the BART 
emission limit is a control efficiency of 99.7 percent on a 365-day 
rolling average. For SO2 from the electric furnace, the BART 
emission limit is a work practice standard prohibiting active aeration. 
For NOX, a 40 tpy limit applies to the converters and 
electric furnace. For PM10, the FIP incorporates by 
reference provisions of the national emission standards for hazardous 
air pollutants for primary copper smelters. Compliance with the 
SO2 emission limit for the converters was required by 
January 1, 2018, and compliance with all other provisions was required 
by September 2, 2016.
e. Hayden Smelter
    The Arizona Regional Haze SIP and Arizona Regional Haze FIP include 
BART requirements for converters 1, 3, 4, and 5, and anode furnaces 1 
and 2 at the Hayden Smelter. Pursuant to a consent decree with the 
United States, Asarco was required to cease operations at the existing 
converters by May 1, 2018.\25\ Accordingly, the anode furnaces are the 
only subject-to-BART units still in operation at the Hayden copper 
smelter. As of September 4, 2017, these units were required to meet an 
annual NOX emission limit of 40 tpy and only be charged with 
blister copper or higher purity copper in order to limit SO2 
emissions.
---------------------------------------------------------------------------

    \25\ Consent Decree No. CV-15-02206-PHX-DLR (D. Ariz) (entered 
December 30, 2015), paragraph 8.
---------------------------------------------------------------------------

f. Sundt Unit 4
    The Arizona Regional Haze FIP includes BART emissions limits and 
the option of a better-than-BART alternative based on a switch from 
coal to natural gas for TEP Sundt Unit 4. On March 14, 2016, TEP 
notified the EPA that it had selected the alternative option and would 
comply with the associated emission limits by the compliance date of 
December 31, 2017.\26\ These limits are 0.25 lb/MMBtu for 
NOX, 0.054 lb/MMBtu for SO2, and 0.010 lb/MMBtu 
(or an alternative limit determined by testing) for PM10.
---------------------------------------------------------------------------

    \26\ Letter dated March 14, 2016, from Erik Bakken, TEP, to 
Kathleen Johnson, EPA Region IX.
---------------------------------------------------------------------------

g. Nelson Lime Plant
    The Arizona Regional Haze FIP includes BART emissions limits for 
Kilns 1 and 2 at the Nelson Lime Plant. The limits for NOX 
are 3.80 lb/ton of lime for Kiln 1 and 2.61 lb/ton of lime for Kiln 2 
on a 12-month rolling average with a compliance date of September 4, 
2017. The limits for SO2 are 9.32 lb/ton of lime for Kiln 1 
and 9.73 lb/ton of lime for Nelson Kiln 2 on a 12-month rolling 
average, and 10.1 tons/day for both kilns combined with a compliance 
date of March 3, 2016.
2. Reasonable Progress Sources
    The Arizona Regional Haze FIP includes NOX emission 
limits and related requirements for CPC Rillito Kiln 4 and PCC 
Clarkdale Kiln 4 under the reasonable progress requirements of the RHR. 
Both kilns are subject to 30-day rolling average NOX limits 
achievable with installation and operation of SNCR, with a compliance 
date of December 31, 2018. The limit for Rillito Kiln 4 is 3.46 lb 
NOX/ton of clinker, and the limit for Clarkdale Kiln 4 is 
2.12 lb NOX/ton of clinker.\27\
---------------------------------------------------------------------------

    \27\ The FIP provided an alternative limit of 810 tons 
NOX/year for Clarkdale Kiln 4, but PCC elected to comply 
with the lb/ton limit. Letter dated May 25, 2018 from Brett Lindsay, 
Environmental and Energy Manager, PCC, to EPA Region IX Enforcement 
Division and Air Division.
---------------------------------------------------------------------------

3. Closure of Existing Facilities
    In its Progress Report, ADEQ explained that Catalyst Paper, which 
was a subject-to-BART source, closed permanently in 2012. The total 
emissions from its boiler unit were more than 250 tons per year of 
NOX and SO2. ADEQ noted in the Arizona Regional 
Haze State Plan that this boiler had a visibility impact of 0.739 
deciviews on the Sierra Ancha Wilderness area and 0.523 deciviews on 
the Superstition Wilderness area. The closure of this facility 
eliminated its emissions and corresponding visibility impacts.
4. Existing Federal and State Regulations
    ADEQ's Progress Report identified several federal and State 
programs that contributed to emissions reductions in visibility-
impairing pollutants.
    The federal programs included in the Progress Report were: The 
Heavy-Duty Highway Rule, which reduced pollution from heavy-duty 
engines and diesel fuel; the Tier 2 and Tier 3 Vehicle and Gasoline 
Sulfur Program, which reduced emissions from passenger and light-duty 
vehicles and gasoline; the Non-Road Engine Program, which reduced 
emissions from non-road engines; the Mercury and Air Toxics Rule, which 
reduced pollution from power plants; and requirements to implement the 
national ambient air quality standards.
    The state regulations described in the Progress Report were: The 
Arizona State Vehicle Emissions Inspection Program, which reduces 
emissions from cars; and Arizona's New Source Review Program, which 
addresses emissions from stationary sources.
5. Smoke Management
    In the Progress Report, ADEQ noted that it implements a certified 
Enhanced Smoke Management Program that works toward a reduction in 
smoke impacts due to prescribed/controlled burning of nonagricultural 
fuels with particular regard to heavy forest fuels. All State lands, 
parks, and forests, as well as any federally-managed lands in Arizona, 
are under the jurisdiction of ADEQ in matters relating to air pollution 
from prescribed burning. The EPA has approved the state and local rules 
that comprise the Enhanced Smoke

[[Page 11461]]

Management Program into the Arizona SIP.\28\
---------------------------------------------------------------------------

    \28\ 71 FR 28270 (May 16, 2006) and 72 FR 25973 (May 8, 2007).
---------------------------------------------------------------------------

B. Summary of Emissions Reductions

    The Arizona Progress Report also includes a summary of the 
emissions reductions achieved throughout the State through 
implementation of the control measures relied upon to achieve 
reasonable progress. ADEQ examined the emissions of SO2, 
NOX, primary organic aerosols (POA), elemental carbon (EC), 
fine soil, fine particulate matter, coarse particulate matter (PMC), 
ammonia (NH3), and volatile organic compounds (VOCs) and 
determined its emissions reductions are adequate to achieve Arizona's 
RPGs. For the statewide emissions inventory, ADEQ used WRAP TSS data 
and other information from WRAP to analyze emissions for 2002 (the 
baseline year), 2008, and 2011 (the most current year for which data 
were available). ADEQ stated in its Progress Report that these years 
were selected because they provided the most comprehensive data. For 
BART sources, EGUs, and other facilities that were subject to 
reasonable progress controls, ADEQ provided annual emissions data from 
2002-2013. The sources of that information were the EPA's CAMD,\29\ the 
2008 and 2011 National Emissions Inventories, and ADEQ's point source 
emissions database.
---------------------------------------------------------------------------

    \29\ CAMD provides emissions and other data for certain large 
stationary sources through the Air Markets Program Data tool 
available at https://ampd.epa.gov/ampd/.
---------------------------------------------------------------------------

    ADEQ provided statewide emissions trends for SO2, 
NOX, POA, EC, Fine Soil, PMC, NH3, and VOCs. The 
emissions trends are summarized in Table 6.

                                   Table 6--Statewide Emissions Trends of Visibility-Impairing Pollutants (Tons/Year)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      SO2          NOX          POA           EC       Fine soil       PMC          NH3          VOC
--------------------------------------------------------------------------------------------------------------------------------------------------------
2002............................................      111,709      368,498       57,754       14,745       25,294      158,099       42,203    1,889,682
2008............................................       86,314      293,114       23,972       10,789       48,288      240,570       42,457      894,010
2011............................................       77,657      264,708       50,057       18,054       50,352      381,306       49,131    1,272,342
Percent (%) Change 2002 to 2011.................         -30%         -28%         -13%          22%          99%         141%          16%         -33%
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: 2015 Arizona Regional Haze 5-Year Progress Report, Table 19, page 48.

    VOC emissions decreased by approximately 33 percent from 2002 to 
2011. However, changes to WRAP modeling techniques over time improved 
the accuracy of biogenic emissions, which makes this direct comparison 
of VOC emissions across years uncertain. These changes included 
different meteorological models, variability of land cover, and 
improved emissions factors based on better sources of data.\30\ Table 7 
summarizes VOC emissions by source.
---------------------------------------------------------------------------

    \30\ WRAP Regional Haze Rule Reasonable Progress Report Support 
Document. Table 3.2-1. http://www.wrapair2.org/documents/SECTIONS%201.0%20-%203.0/WRAP_RHRPR_Sec_1-3_Background_Info.pdf.

                                  Table 7--VOC Emissions by Source (Tons/Year)
----------------------------------------------------------------------------------------------------------------
                                                                       2002            2008            2011
----------------------------------------------------------------------------------------------------------------
Point...........................................................           5,464           3,490           3,414
Anthropogenic Fire..............................................             855           5,781          10,053
Natural Fire....................................................          36,377           1,330         222,314
Biogenic........................................................       1,576,698         686,255         880,219
Area............................................................         102,918         100,256          67,622
WRAP Area O&G...................................................              46              12              65
On-Road Mobile..................................................         110,424          54,589          49,387
Off-Road Mobile.................................................          56,901          42,297          39,268
Fugitive/Road Dust..............................................            0.00            0.00            0.00
WB Dust.........................................................            0.00            0.00            0.00
                                                                 -----------------------------------------------
    Total.......................................................       1,889,682         894,010       1,272,342
----------------------------------------------------------------------------------------------------------------
Source: 2015 Arizona Regional Haze 5-Year Progress Report, page 50.

    As shown in Table 6, total emissions of SO2 and 
NOX decreased consistently from 2002 to 2011. The 
approximately 30 percent reduction in SO2 from 2002 to 2011 
was mainly attributed to controls on point source facilities. The 
approximately 29 percent reduction in NOX was mainly 
attributed to point sources and on-road mobile sources.
    Reported total PM emissions (categorized as PMC, fine soil, EC, and 
POA) increased consistently from 2002 to 2011. The total increase from 
2002 to 2011 was approximately 92 percent. The largest contributor to 
this increase was PMC, which was primarily made up of windblown dust 
and fugitive/road dust. Not only did the amount of reported PMC 
increase at each inventory year, but the percentage of PMC within the 
total particulate matter emissions also increased over time. Some of 
this change may be due to improvements in WRAP methodologies for 
estimating PMC emissions. As we noted in our supplemental Phase 2 
proposal on the Arizona Regional Haze SIP, emissions inventories for 
particulate matter may be uncertain, largely because emissions of 
fugitive/road dust and windblown dust are difficult to calculate 
accurately.\31\ Therefore, for purposes of Regional Haze, we generally 
consider IMPROVE monitoring data for these pollutants to be more 
informative than emissions inventories. As described below, the overall 
monitoring data for all Class I areas in Arizona have shown 
improvements in visibility for the 20 percent most and least impaired 
days between the baseline (2000-2004) and current (2009-2013) 
visibility periods. However, as shown in Table 8, species-specific 
monitoring data show that visibility impairment from coarse mass and 
fine soil increased in some Class I areas and decreased in other areas 
between the baseline and progress

[[Page 11462]]

periods. Therefore, while the monitoring data generally show progress, 
as we noted in the supplemental Phase 2 proposal on the Arizona 
Regional Haze SIP, it will be necessary to more closely examine the 
potential visibility impacts of fugitive and road dust on Arizona's 
Class I areas in the second and future planning periods.\32\
---------------------------------------------------------------------------

    \31\ 78 FR 29292, 29297 (May 20, 2013).
    \32\ Id. at 29298.

              Table 8--Visibility Impairment From Fine Soil and PMC on 20 Percent Worst Days (Mm-1)
----------------------------------------------------------------------------------------------------------------
                                                  Fine soil                                 PMC
                                   -----------------------------------------------------------------------------
 IMPROVE monitor    Class I area      Baseline     Current     Difference    Baseline     Current
                                     2000-2004    2009-2013        a        2000-2004    2009-2013    Difference
----------------------------------------------------------------------------------------------------------------
BALD1...........  Mount Baldy               1.1          1.3          0.2          2.8          3.5          0.7
                   Wilderness.
CHIR1...........  Chiricahua                2.7          1.9         -0.8          8.6          7.4         -1.2
                   National
                   Monument,
                   Chiricahua
                   Wilderness &
                   Galiuro
                   Wilderness.
GRCA2...........  Grand Canyon              1.3          1.2         -0.1          3.5          3.2         -0.3
                   National Park.
IKBA1...........  Mazatzal                  2.6          2.3         -0.3          6.2          6.2          0.0
                   Wilderness &
                   Pine Mountain
                   Wilderness.
PEFO1...........  Petrified Forest          2.0          2.1          0.1          7.3          6.4         -0.9
                   National Park.
SAGU1...........  Saguaro National          3.4          2.5         -0.9          7.1          8.0          0.9
                   Monument--East
                   Unit.
SAWE1...........  Saguaro National          5.8          3.6         -2.2         12.8         11.2         -1.6
                   Monument--West
                   Unit.
SIAN1...........  Sierra Ancha              2.2          1.8         -0.4          5.9          4.4         -1.5
                   Wilderness.
SYCA2...........  Sycamore Canyon           6.8          5.6         -1.2          9.4          9.8          0.4
                   Wilderness.
----------------------------------------------------------------------------------------------------------------
a Calculated as the difference between the baseline period (2000-04) and current conditions (2009-13). A
  negative difference indicates a reduction in haze, i.e., improved visibility.
Source: 2015 Arizona Regional Haze 5-Year Progress Report, pages 26-44.

    Under the Arizona Regional Haze SIP and FIP, stationary sources 
were required to reduce SO2, NOX, and 
PM10. Arizona's Progress Report included annual emissions 
data from 2002-2013 for BART sources that are EGUs, BART sources that 
are not EGUs, and non-BART sources that were subject to reasonable 
progress controls for visibility-impairing emissions. Although there 
was variation in emissions during the years between 2002 and 2013, the 
emissions for all sources in 2013 were lower than emissions in 2002. 
For BART EGU sources, ADEQ noted that although emissions had decreased 
from 2002-2013, heat input had increased, indicating that the emissions 
reductions were the result of pollution controls, not reduced 
operations. ADEQ also noted that for all these facilities, further 
reductions were expected to occur by 2018, either due to BART controls 
or to reasonable progress controls.\33\ Table 9 summarizes stationary 
source emissions.
---------------------------------------------------------------------------

    \33\ See section III.A above for a summary of these controls and 
the associated compliance dates.

                                                    Table 9--Stationary Source Emissions (Tons/Year)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                              BART sources--EGUs                           BART sources--non-EGUs                         Non-BART, non-EGU
     Year      -----------------------------------------------------------------------------------------------------------------------------------------
                      SO2             NOX            PM10            SO2            NOX            PM10           SO2            NOX            PM10
--------------------------------------------------------------------------------------------------------------------------------------------------------
        2002          46,798          32,714       \a\ 1,215         26,330          3,080            996            292          8,895          1,600
        2013          11,025          25,337           1,322         23,364          1,826            607             10          2,649            301
--------------------------------------------------------------------------------------------------------------------------------------------------------
a PM10 data were not available for Sundt (Irvington) Generating Station.
Source: 2015 Arizona Regional Haze 5-Year Progress Report, Tables 13-15.

    Arizona's Progress Report also described PM2.5 emissions 
that were averted from 2009-2014 through its Enhanced Smoke Management 
Program.

C. Summary of Visibility Conditions

    ADEQ's Progress Report provided visibility data for each of the 
State's Class I areas during the baseline period (2000-2004), the 
current period for the progress report (2009-2013), and for the rolling 
5-year periods between the baseline and current periods. The Report 
compared those data with the 2018 RPGs for each area. The Report also 
compared the visibility progress to the Uniform Rate of Progress (URP) 
\34\ for the worst days. However, the RHR does not require a progress 
report to compare current or projected visibility conditions to the 
URP.\35\ Consequently, the RPGs are the relevant comparison points for 
evaluating whether the progress report meets the RHR requirements for 
reporting visibility progress during this first planning period. These 
RPGs are listed in Table 10 along with the baseline and current (as of 
the submission of the Progress Report) visibility conditions.
---------------------------------------------------------------------------

    \34\ The URP is a straight line from the baseline visibility 
condition (5-year annual average from 2000-2004) to the estimated 
natural background condition in 2064, as measured on the 20 percent 
best and worst days. The URP values for 2018 are the number of 
deciviews where the lines drawn to 2064 for best and worst days 
intersect 2018.
    \35\ 79 FR 52419, 52426 (September 3, 2014).

                          Table 10--Arizona Class I Area Visibility Conditions on the 20 Percent Most and Least Impaired Days a
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                    Best days (deciviews)                  Worst days (deciviews)
                                                                           -----------------------------------------------------------------------------
              Improve monitor                         Class I area            Baseline                  Current      Baseline                  Current
                                                                             2000-2004     2018 RPG    2009-2013    2000-2004     2018 RPG    2009-2013
--------------------------------------------------------------------------------------------------------------------------------------------------------
BALD1......................................  Mount Baldy Wilderness.......          3.0          2.8          2.7       b 11.8         11.4         10.5
CHIR1......................................  Chiricahua National Monument,          4.9          4.8          4.1         13.4         13.2         12.1
                                              Chiricahua Wilderness &
                                              Galiuro Wilderness.
GRCA2......................................  Grand Canyon National Park...          2.2          2.0          1.8         11.7         11.0         10.9

[[Page 11463]]

 
IKBA1......................................  Mazatzal Wilderness & Pine             5.4          5.1          4.4         13.3         12.6         12.0
                                              Mountain Wilderness.
PEFO1......................................  Petrified Forest National              5.0          4.6          4.1         13.2         12.6         11.9
                                              Park.
SAGU1......................................  Saguaro National Monument--            6.9          6.9          6.1         14.8         14.7         12.6
                                              East Unit.
SAWE1......................................  Saguaro National Monument--            8.6          8.2          7.5         16.2         15.9         14.2
                                              West Unit.
SIAN1......................................  Sierra Ancha Wilderness......          6.2         5.78          4.9         13.7        13.05         12.2
SYCA2......................................  Sycamore Canyon Wilderness...          5.6         5.39          5.1         15.3        14.92         14.6
TONT1......................................  Superstition Wilderness......          6.5         6.09          5.2         14.2        13.72         12.7
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: 2015 Arizona Regional Haze 5-Year Progress Report, Table 17.
a Due to rounding, some values in this table differ slightly from those in the Arizona Regional Haze SIP and Arizona Regional Haze FIP.
\b\ The baseline worst days value for BALD1 was incorrectly listed as 11.95 deciviews in Tables 9 and 10 in the EPA's Phase 3 FIP final rule. 79 FR
  52469-52470 (September 3, 2014). The correct value of 11.85 deciviews is found in Arizona's 2011 Submittal, Table 6.3.

    Based on the information in Chapter 4 of the Progress Report, 
Arizona demonstrated that all Class I areas experienced improvements in 
visibility (i.e., reductions in deciviews) for the 20-percent most and 
least impaired days between the baseline (2000-2004) and current (2009-
2013) visibility periods, as summarized in Table 10 above and shown in 
Table 17 of the Progress Report. The same table also shows that the 
five-year average worst days and best days during the current (2009-
2013) period were below (i.e., better than) the 2018 RPGs. Thus, all of 
the State's Class I areas are on track to meet or surpass their 2018 
RPGs. As part of a comprehensive SIP revision due by July 31, 2021, the 
State will be required to adopt 2028 RPGs, which will reflect new 
control measures adopted to meet the requirements of the Regional Haze 
Rule and other CAA requirements.\36\
---------------------------------------------------------------------------

    \36\ 40 CFR 51.308(f)(3)(i).
---------------------------------------------------------------------------

    In addition, the Progress Report explains that the significant 
reductions in NOX and SO2 emissions discussed in 
the previous section have also mitigated Arizona's contribution to 
visibility impairment in Class I areas in nearby states.\37\
---------------------------------------------------------------------------

    \37\ 2015 Arizona Regional Haze 5-Year Progress Report, Table 
17.
---------------------------------------------------------------------------

    The Progress Report also contains a review of Arizona's visibility 
monitoring strategy. In the Progress Report, ADEQ notes that the Grand 
Canyon--Indian Garden IMPROVE monitoring station shut down in 2013. The 
Report states that Arizona uses the GRCA2 monitoring station for Grand 
Canyon National Park, so the closure of the Indian Gardens monitor will 
not affect the reliability of the IMPROVE network in Arizona.

D. Determination of Adequacy

    Within the Progress Report, the State of Arizona provided a 
negative declaration stating that further revision of the existing 
implementation plan is not needed in accordance with 40 CFR 
51.308(h)(1). The basis for the State's negative declaration is the 
information in the Progress Report and the determination that Arizona 
is currently on track to achieve all 2018 RPGs for the State's Class I 
areas. Given the large reductions in SO2 and NOX 
emissions and the significant improvements in visibility at the State's 
Class I areas achieved during the planning period, the EPA proposes to 
approve Arizona's determination that the existing Arizona SIP requires 
no substantive revisions at this time to achieve the established 2018 
RPGs for Class I areas. As mentioned above, the State is required to 
submit a comprehensive SIP revision for the next planning period, 
including RPGs for 2028, by July 31, 2021.\38\
---------------------------------------------------------------------------

    \38\ 40 CFR 51.308(f)(3)(i).
---------------------------------------------------------------------------

E. Consultation With Federal Land Managers (FLMs)

    The State of Arizona invited the FLMs to comment on its draft 
progress report on August 24, 2015. Arizona received comments from one 
FLM, the National Park Service, which indicated that the Progress 
Report met the applicable requirements and requested additional 
information and other minor changes. ADEQ responded to the FLM comments 
and revised the Progress Report accordingly, as documented in Appendix 
A of the Progress Report. The EPA proposes to find that Arizona has 
addressed the requirements for FLM consultation in 40 CFR 51.308(i).

IV. The EPA's Proposed Action

    The EPA is proposing to approve the Arizona Regional Haze Progress 
Report submitted to the EPA on November 12, 2015, as meeting the 
applicable requirements of the CAA and RHR, as set forth in 40 CFR 
51.308(g). The EPA proposes to approve Arizona's determination that the 
existing regional haze implementation plan is adequate to meet the 
State's 2018 visibility goals and requires no substantive revision at 
this time. We also propose to find that Arizona fulfilled the 
requirements in 40 CFR 51.308(i) regarding state coordination with 
FLMs.

V. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the CAA and applicable 
federal regulations.\39\ Thus, in reviewing SIP submissions, the EPA's 
role is to approve state choices, provided that they meet the criteria 
of the CAA. Accordingly, this proposed action merely approves state law 
as meeting federal requirements and does not impose additional 
requirements beyond those imposed by state law. For that reason, this 
proposed action:
---------------------------------------------------------------------------

    \39\ 42 U.S.C. 7410(k); 40 CFR 52.02(a).
---------------------------------------------------------------------------

     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 
2011);
     Is not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory action because actions such as SIP approvals are 
exempted under Executive Order 12866;
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely

[[Page 11464]]

affect small governments, as described in the Unfunded Mandates Reform 
Act of 1995 (Pub. L. 104-4);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because this rulemaking does not involve technical standards; and
     Does not provide the EPA with the discretionary authority 
to address, as appropriate, disproportionate human health or 
environmental effects, using practicable and legally permissible 
methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, this proposed action does not apply on any Indian 
reservation land or in any other area where the EPA or an Indian tribe 
has demonstrated that a tribe has jurisdiction. In those areas of 
Indian country, the rule does not have tribal implications as specified 
by Executive Order 13175 (65 FR 67249, November 9, 2000).

List of Subjects in 40 CFR Part 52

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

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

    Dated: March 14, 2019.
Deborah Jordan,
Acting Regional Administrator, Region IX.
[FR Doc. 2019-05769 Filed 3-26-19; 8:45 am]
 BILLING CODE 6560-50-P