[Federal Register Volume 85, Number 75 (Friday, April 17, 2020)]
[Proposed Rules]
[Pages 21341-21351]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-07941]



[[Page 21341]]

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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R08-OAR-2019-0623; FRL-10007-20-Region 8]


Approval and Promulgation of Implementation Plans; Wyoming; 
Regional Haze 5-Year Progress Report State Implementation Plan

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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

SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve a regional haze progress report State Implementation Plan (SIP) 
revision submitted by the State of Wyoming on November 28, 2017. The 
revision addresses the requirements for states to submit periodic 
reports describing progress toward reasonable progress goals 
established for regional haze and a determination of adequacy of the 
State's existing regional haze SIP and federal implementation plan 
(FIP). The regional haze progress report SIP revision also includes a 
revision to the Best Available Retrofit Technology (BART) requirements 
for Unit 3 at the Naughton Power Plant. The EPA acted on the BART 
revision for the Naughton Power Plant in a previous rulemaking and is 
not proposing to act on the BART revision in this rulemaking. The EPA 
is taking this action pursuant to section 110 of the Clean Air Act 
(CAA).

DATES: Written comments must be received on or before May 18, 2020.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R08-
OAR-2019-0623, 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://www2.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 and Radiation 
Division, 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: Jaslyn Dobrahner, Air and Radiation 
Division, EPA, Region 8, Mailcode 8ARD-IO, 1595 Wynkoop Street, Denver, 
Colorado 80202-1129, (303) 312-6252, dobrahner.jaslyn@epa.gov.

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

I. What action is the EPA proposing?

    On November 28, 2017, Wyoming submitted a Progress Report SIP 
revision (Progress Report) which: (1) Detailed the progress made toward 
achieving progress for improving visibility at Class I areas,\1\ and 
(2) declared a determination of adequacy of the State's regional haze 
plan to meet reasonable progress goals. The Progress Report also 
included a revision to the BART requirements for Unit 3 at the Naughton 
Power Plant. However, the EPA acted on the BART revision for the 
Naughton Power Plant in a previous rulemaking and is therefore not 
proposing to act on the BART revision in this rulemaking.\2\ The State 
provided an opportunity for public comment through public hearings held 
on January 15, 2014 and September 26, 2017, and provided Federal Land 
Managers (FLMs) an opportunity to comment on the Progress Report.\3\ 
The EPA is proposing to approve Wyoming's November 28, 2017 regional 
haze Progress Report SIP submittal.
---------------------------------------------------------------------------

    \1\ 42 U.S.C. 7491(a). Areas designated as mandatory Class I 
Federal areas consist of national parks exceeding 6000 acres, 
wilderness areas and national memorial parks exceeding 5000 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.''
    \2\ 84 FR 10433 (March 21, 2019).
    \3\ Due to new permit requirements for Unit 3 at the Naughton 
Power Plant added to the Progress Report in early 2017, a second 
public comment period was provided.
---------------------------------------------------------------------------

II. Background

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

    In section 169A of the 1977 CAA Amendments, Congress created a 
program for protecting visibility in the nation's national parks and 
wilderness areas. This section of the CAA establishes ``as a national 
goal the prevention of any future, and the remedying of any existing, 
impairment of visibility in mandatory Class I Federal areas which 
impairment results from manmade air pollution.''
    The EPA promulgated a rule to address regional haze on July 1, 
1999.\4\ The Regional Haze Rule revised the existing visibility 
regulations \5\ 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. The EPA revised the 
Regional Haze Rule on January 10, 2017.\6\
---------------------------------------------------------------------------

    \4\ 64 FR 35714, 35714 (July 1, 1999) (codified at 40 CFR part 
51, subpart P).
    \5\ 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, 
80084 (December 2, 1980).
    \6\ 82 FR 3078 (January 10, 2017).
    \7\ 42 U.S.C. 7410(a), 7491, and 7492(a); CAA sections 110(a), 
169A, and 169B.
---------------------------------------------------------------------------

    The CAA requires each state to develop a SIP to meet various air 
quality requirements, including protection of visibility.\7\ Regional 
haze SIPs must assure reasonable progress toward the national goal of 
achieving natural visibility conditions in Class I areas. A state must 
submit its SIP and SIP revisions to the EPA for approval. Once

[[Page 21342]]

approved, a SIP is enforceable by the EPA and citizens under the CAA. 
If a state elects not to make a required SIP submittal, fails to make a 
required SIP submittal, or if we find that a state's required submittal 
is incomplete or not approvable, then we must promulgate a FIP to fill 
this regulatory gap.\8\
---------------------------------------------------------------------------

    \8\ 42 U.S.C. 7410(c)(1).
    \9\ The Colorado Plateau is a high, semi-arid tableland in 
southeast Utah, northern Arizona, northwest New Mexico, and western 
Colorado. The 16 mandatory Class I areas are: Grand Canyon National 
Park, Mount Baldy Wilderness, Petrified Forest National Park, 
Sycamore Canyon Wilderness, Black Canyon of the Gunnison National 
Park Wilderness, Flat Tops Wilderness, Maroon Bells Wilderness, Mesa 
Verde National Park, Weminuche Wilderness, West Elk Wilderness, San 
Pedro Park Wilderness, Arches National Park, Bryce Canyon National 
Park, Canyonlands National Park, Capital Reef National Park and Zion 
National Park.
---------------------------------------------------------------------------

B. Requirements for Regional Haze SIPs Submitted Under 40 CFR 51.309

    The EPA's Regional Haze Rule provides two paths to address regional 
haze. One is 40 CFR 51.308, requiring states to perform individual 
point source BART determinations and evaluate the need for other 
control strategies. The other method for addressing regional haze is 
through 40 CFR 51.309, and is an option for states termed the 
``Transport Region States'' including Wyoming. Transport Region States 
can adopt regional haze strategies based on recommendations from the 
Grand Canyon Visibility Transport Commission (GCVTC) for protecting the 
16 Class I areas on the Colorado Plateau.\9\ The GCVTC submitted an 
annex to the EPA, known as the SO2 Backstop Trading Program, 
containing annual sulfur dioxide (SO2) emissions reduction 
milestones and detailed provisions of a backstop trading program to be 
implemented automatically if measures failed to achieve the 
SO2 milestones. Wyoming submitted a regional haze SIP under 
section 40 CFR 51.309 to address stationary source SO2 
emissions reductions through the SO2 Backstop Trading 
Program and submitted a regional haze SIP under section 40 CFR 
51.309(g) to address stationary source nitrogen oxide (NOX) 
and particulate matter (PM) emissions reductions.

C. Requirements for the Five-Year Regional Haze Progress Report SIP

    Under both 40 CFR 51.308 and 40 CFR 51.309, states are required to 
submit progress reports that evaluate progress towards the reasonable 
progress goals for each mandatory federal 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. In addition, the provisions also 
require states to submit, at the same time as the progress report, a 
determination of adequacy of the state's existing regional haze plan. 
The first progress report must be in the form of a SIP revision and is 
due 5 years after submittal of the initial regional haze SIP.
    As a Transport Region State, Wyoming submitted its Progress Report 
SIP under 40 CFR 51.309, and exercised the option to meet the 
requirements contained in 40 CFR 51.309 for regional haze 
implementation plans.\10\ The requirements for Transport Region State 
progress reports are similar to those for other states, but the 
requirements for the reports are codified at 40 CFR 51.309(d)(10).
---------------------------------------------------------------------------

    \10\ Wyoming Department of Environmental Quality, Wyoming State 
Implementation Plan, 5-Year Progress Report. (Wyoming Progress 
Report), Governor's letter. (November 17, 2017).
---------------------------------------------------------------------------

D. Regulatory and Legal History of the Wyoming Regional Haze SIP and 
FIP

    On January 12, 2011, and April 19, 2012, Wyoming submitted regional 
haze SIP revisions addressing the requirements of 40 CFR 51.309 that 
superseded and replaced regional haze SIP revisions submitted on 
December 24, 2003, May 27, 2004 and November 21, 2008. On December 12, 
2012, the EPA approved the SIP revisions as meeting the requirements of 
the Regional Haze Rule with the exception of 40 CFR 51.309(d)(4)(vii) 
and 40 CFR 51.309(g). On January 30, 2014, the EPA issued a final rule 
partially approving and partially disapproving the SIP revisions as 
meeting the requirements of 40 CFR 51.309(g), and promulgating a 
federal implementation plan (FIP) for those portions of the SIP that 
were disapproved (together referred to as the regional haze 
implementation plan).\11\ Several parties challenged various aspects of 
the 2014 final rule pertaining to NOX BART emission 
limits.\12\ On September 9, 2014, the U.S. Court of Appeals for the 
Tenth Circuit stayed various NOX BART emission limits.\13\ 
Subsequent revisions were made to the regional haze SIP on March 21, 
2019, and to the regional haze SIP and FIP on May 20, 2019.\14\
---------------------------------------------------------------------------

    \11\ 79 FR 5032 (January 30, 2014).
    \12\ Basin Electric, PacifiCorp, Powder River Basin Resource 
Council, National Parks Conservation Association, Sierra Club, and 
the State of Wyoming challenged various NOX BART emission 
limits in the final rule. Basin Electric Cooperative v. EPA, No. 14-
9533 (10th Cir.); Wyoming v. EPA, No. 14-9529 (10th Cir.); 
PacifiCorp v. EPA, No. 14.9534 (10th Cir.); Powder River Basin 
Resource Council, et al. v. EPA, No. 14-9530 (10th Cir.).
    \13\ Wyoming v. EPA, No. 14-9529, ECF No. 10204804.
    \14\ On March 21, 2019, the EPA approved a SIP revision to the 
BART requirements for Unit 3 at the Naughton Power Plant. 84 FR 
10433 (March 21, 2019). On May 20, 2019, the EPA approved SIP 
revisions and revised the FIP to: (1) Modify the SO2 
emissions reporting requirements for Laramie River Station Units 1 
and 2, (2) revise the NOX emission limits for Laramie 
River Units 1, 2 and 3, and (3) establish an SO2 emission 
limit averaged annually across both Laramie River Station Units 1 
and 2. 84 FR 22711 (May 20, 2019).
---------------------------------------------------------------------------

III. The EPA's Evaluation of Wyoming's Progress Report and Adequacy 
Determination

A. Regional Haze Progress Report

    Wyoming's Progress Report must meet the requirements set forth in 
40 CFR 51.309(d)(10)(i). Wyoming's Progress Report must also include a 
determination of the adequacy of the existing implementation plan to 
ensure reasonable progress. 40 CFR 51.309(d)(10)(ii).
1. Status of Implementation of Control Measures
    Wyoming's Progress Report must include a description of the status 
of implementation of all control measures included in the 
implementation plans for achieving reasonable progress goals for Class 
I areas both within and outside of the State. 40 CFR 
51.309(d)(10)(i)(A).
    In its Progress Report, Wyoming summarized the regional haze 
measures that were relied upon in the regional haze implementation 
plan, as well as SO2 emissions reduction strategies 
implemented by sources in New Mexico, Utah, and Wyoming under the 
SO2 Backstop Trading Program. The State referenced the 
SO2 emissions for sources associated with the SO2 
Backstop Trading Program \15\ found within the 2011 Regional 
SO2 Emissions and Milestones Report (Table 1).\16\
---------------------------------------------------------------------------

    \15\ Wyoming Progress Report, pages 6, 10.
    \16\ Western Regional Air Partnership, 2011 Regional 
SO2 Emissions and Milestone Report. (February 20, 2013).

[[Page 21343]]



  Table 1--Reported Emissions for Sources Associated With the Backstop
                          Trading Program \17\
------------------------------------------------------------------------
                                                           Reported 2011
                                                           SO2 emissions
           State                      Plant name              (tons)
 
------------------------------------------------------------------------
NM.........................  Agave Energy Co./Agave                    0
                              Dagger Draw Gas Plant.
NM.........................  BP America Production/                1,704
                              Empire Abo Plant.
NM.........................  DCP Midstream/Artesia Gas               326
                              Plant.
NM.........................  DCP Midstream/Eunice Gas              2,921
                              Plant.
NM.........................  DCP Midstream/Linam Ranch             1,304
                              Gas Plant.
NM.........................  Duke--Magnum/Pan Energy--                 0
                              Burton Flats.
NM.........................  Duke Energy/Dagger Draw Gas               0
                              Plant.
NM.........................  Targa Midstream Services,               718
                              LP/Eunice Gas Plant.
NM.........................  Frontier Field Services/              2,986
                              Maljamar Gas Plant.
NM.........................  Giant Industries/Ciniza                 125
                              Refinery (Gallup).
NM.........................  J L Davis Gas Processing/               675
                              Denton Plant.
NM.........................  Marathon Oil/Indian Basin               133
                              Gas Plant.
NM.........................  Navajo Refining Co/Artesia               45
                              Refinery.
NM.........................  Public Service Co of New              4,741
                              Mexico/San Juan Generating
                              Station.
NM.........................  Raton Pub. Service/Raton                  0
                              Power Plant.
NM.........................  Southern Union Gas/Jal #3..           1,319
NM.........................  Targa Midstream Services,                 0
                              LP/Eunice South Gas Plant.
NM.........................  Targa Midstream Services,               771
                              LP/Monument Plant.
NM.........................  Targa Midstream Services,               251
                              LP/Saunders Plant.
NM.........................  Tri-State Gen &                       1,257
                              Transmission/Escalante
                              Station.
NM.........................  Western Gas Resources/San               621
                              Juan River Gas Plant.
NM.........................  Western Refining Southwest                6
                              Inc./Sand Juan Refinery
                              (Bloomfield).
UT.........................  Brigham Young University--               99
                              Main Campus.
UT.........................  Chevron Products Co--Salt                24
                              Lake Refinery.
UT.........................  Flying J Refinery--(Big                 192
                              West Oil Company).
UT.........................  Graymont Western U.S. Inc--              16
                              Cricket Mountain Plant.
UT.........................  Holcim--Devil's Slide Plant             344
UT.........................  Holly Refining and                      131
                              Marketing Co--Phillips
                              Refinery.
UT.........................  Intermountain Power Service           4,934
                              Corporation--Intermountain
                              Generating Station.
UT.........................  Kennecott Utah Copper Corp--          1,704
                              Power Plant/Lab/Tailings
                              Impoundment.
UT.........................  Kennecott Utah Copper Corp--            696
                              Smelter and Refinery.
UT.........................  Materion Natural Resources--              0
                              Delta Mill.
UT.........................  PacifiCorp--Carbon Power              7,740
                              Plant.
UT.........................  PacifiCorp--Hunter Power              4,661
                              Plant.
UT.........................  PacifiCorp--Huntington                2,529
                              Power Plant.
UT.........................  Patara Midstream LLC--                   25
                              Lisbon Natural Gas
                              Processing Plant.
UT.........................  Sunnyside Cogeneration                  544
                              Associates--Sunnyside
                              Cogeneration Facility.
UT.........................  Tesoro West Coast--Salt                 795
                              Lake City Refinery.
UT.........................  Utelite Corporation--Shale              130
                              Processing.
WY.........................  American Colloid Mineral                 63
                              Co--East Colony.
WY.........................  American Colloid Mineral                 50
                              Co--West Colony.
WY.........................  Basin Electric--Dry Fork                279
                              Station.
WY.........................  Basin Electric--Laramie               9,402
                              River Station.
WY.........................  Black Hills Corporation--               789
                              Neil Simpson I.
WY.........................  Black Hills Corporation--               542
                              Neil Simpson II.
WY.........................  Black Hills Corporation--                 0
                              Osage Plant.
WY.........................  Black Hills Corporation--               559
                              Wygen I.
WY.........................  Cheyenne Light Fuel and                 215
                              Power Company--Wygen II.
WY.........................  Black Hills Corporation--               256
                              Wygen III.
WY.........................  Burlington Resources--                  223
                              Bighorn Wells.
WY.........................  Burlington Resources--Lost            1,543
                              Cabin Gas Plant.
WY.........................  Chevron USA--Carter Creek               100
                              Gas Plant.
WY.........................  Chevron USA--Table Rock                   0
                              Field.
WY.........................  Chevron USA--Table Rock Gas              44
                              Plant.
WY.........................  Chevron USA--Whitney Canyon/              2
                              Carter Creek Wellfield.
WY.........................  Devon Energy Production                   5
                              Co., L.P.--Beaver Creek
                              Gas Field.
WY.........................  Devon Gas Services, L.P.--              158
                              Beaver Creek Gas Plant.
WY.........................  Encore Operating LP--Elk                847
                              Basin Gas Plant.
WY.........................  Exxon Mobil Corporation--               156
                              Labarge Black Canyon
                              Facility.
WY.........................  Exxon Mobil Corporation--               946
                              Shute Creek.
WY.........................  FMC Corp--Green River                 2,876
                              Sodium Products.
WY.........................  FMC Wyoming Corporation                 189
                              Granger Soda Ash Plant.
WY.........................  Frontier Oil & Refining                 253
                              Company--Cheyenne Refinery.
WY.........................  Hiland Partners, LLC--                   45
                              Hiland Gas Plant.
WY.........................  Marathon Oil Co--Oregon                 247
                              Basin Gas Plant.
WY.........................  Marathon Oil Co--Oregon                  96
                              Basin Wellfield.
WY.........................  Merit Energy Company--Brady             209
                              Gas Plant.
WY.........................  Merit Energy Company--                    1
                              Whitney Facility.
WY.........................  Merit Energy Company--                    0
                              Whitney Canyon Wellfield.
WY.........................  Mountain Cement Company--               283
                              Laramie Plant.

[[Page 21344]]

 
WY.........................  P4 Production, L.L.C.--Rock             706
                              Springs Coal Calcining
                              Plant.
WY.........................  PacifiCorp--Dave Johnston            11,306
                              Plant.
WY.........................  PacifiCorp--Jim Bridger               9,689
                              Plant.
WY.........................  PacifiCorp--Naughton Plant.          20,461
WY.........................  PacifiCorp--Wyodak Plant...           2,387
WY.........................  Simplot Phosphates LLC--              1,502
                              Rock Springs Plant.
WY.........................  Sinclair Oil Company--                  505
                              Sinclair Refinery.
WY.........................  Sinclair Wyoming Refining               241
                              Company--Casper Refinery.
WY.........................  Solvay Chemicals--Soda Ash               46
                              Plant (Green River
                              Facility).
WY.........................  TATA Chemicals (Soda Ash              5,098
                              Partners)--Green River
                              Plant.
WY.........................  The Western Sugar                       182
                              Cooperative--Torrington
                              Plant.
WY.........................  University of Wyoming--Heat             187
                              Plant.
WY.........................  Wyoming Refining--Newcastle             324
                              Refinery.
------------------------------------------------------------------------

    Additionally, Wyoming provided the status of control measures 
associated with PM, NOX, and SO2 and emissions on 
units subject to BART and reasonable progress within the regional haze 
implementation plan (Table 2).
---------------------------------------------------------------------------

    \17\ In 2011, three states participated in the SO2 
Backstop Trading Program. SO2 emissions from all three 
participating states are recorded and collectively compared to the 
milestone.

                          Table 2--Control Measures and Updates for Sources Subject to BART and Reasonable Progress in Wyoming
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               PM10 emission limit                            NOX emission limit     SO2 emission limit
                Unit                     PM control type                                NOX control type
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   SIP Emission Limits
                                                              FIP Emission Limits
--------------------------------------------------------------------------------------------------------------------------------------------------------
Basin Electric--Laramie River Unit   Electrostatic           0.030 lb/MMBtu........  Selective Catalytic    0.06 lb/MMBtu (30-day  0.12 lb/MMBtu
 1 (550 Mega Watt (MW)).              Precipitator (ESP)                              Reduction (SCR)        rolling) *.            (averaged annually
                                      (completed).                                    (completed).                                  across Units 1 and
                                                                                                                                    2).
Basin Electric--Laramie River Unit   ESP (completed).......  0.030 lb/MMBtu........  Selective              0.15 lb/MMBtu (30-day
 2 (550 MW).                                                                          Noncatalytic           rolling) *.
                                                                                      Reduction (SNCR)
                                                                                      (completed).
Basin Electric--Laramie River Unit   ESP (completed).......  0.030 lb/MMBtu........  SNCR 12/30/2018 *      0.15 lb/MMBtu (30-day  N/A.
 3 (550 MW).                                                                          (completed).           rolling) *.
PacifiCorp--Dave Johnston Unit 3     Fabric Filter           0.015 lb/MMBtu........  New Low NOX Burners    0.28 lb/MMBtu (30-day  N/A.
 (230 MW).                            (completed).                                    (LNB) + Overfire Air   rolling) and
                                                                                      (OFA) and shut down    shutdown; or 0.07 lb/
                                                                                      by 12/31/2027; or      MMBtu (30-day
                                                                                      New LNB + OFA and      rolling).
                                                                                      SCR no later than 3/
                                                                                      4/2019 **.
PacifiCorp--Wyodak Unit 1 (335 MW).  Fabric Filter           0.015 lb/MMBtu........  SCR, no later than 3/  0.07 lb/MMBtu (30-day  N/A.
                                      (completed).                                    4/2019 [Dagger].       rolling) [Dagger].
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   SIP Emission Limits
--------------------------------------------------------------------------------------------------------------------------------------------------------
PacifiCorp--Dave Johnston Unit 4     Fabric Filter           0.015 lb/MMBtu........  LNB + OFA (completed)  0.15 lb/MMBtu (30-day  N/A.
 (330 MW).                            (completed).                                                           rolling).
PacifiCorp--Naughton Unit 1 (160     ESP + Flue Gas          0.040 lb/MMBtu........  LNB + OFA (completed)  0.26 lb/MMBtu (30-day  N/A.
 MW).                                 Conditioning (FGC)                                                     rolling).
                                      (completed).
PacifiCorp--Naughton Unit 2 (210     ESP + FGC (completed).  0.040 lb/MMBtu........  LNB + OFA (completed)  0.26 lb/MMBtu (30-day  N/A.
 MW).                                                                                                        rolling).
PacifiCorp--Naughton Unit 3 (330 MW  Natural Gas Conversion  0.008 lb/MMBtu........  Natural Gas            0.12 lb/MMBtu (30-day  N/A.
 with max annual heat input of 40%)   by 1/30/19.                                     Conversion by 1/30/    rolling).
 [dagger].                                                                            19; new LNB + Flue
                                                                                      Gas Recirculation
                                                                                      (FGR) (in progress)
                                                                                      [dagger][dagger].
PacifiCorp--Jim Bridger Unit 1 (530  ESP + FGC (completed).  0.030 lb/MMBtu........  LNB + OFA + SCR (to    0.26 lb/MMBtu (30-day  N/A.
 MW).                                                                                 be completed 12/31/    rolling) by 2019;
                                                                                      2022).                 0.07 lb/MMBtu (SCR).
PacifiCorp--Jim Bridger Unit 2 (530  ESP + FGC (completed).  0.030 lb/MMBtu........  LNB + OFA + SCR (to    0.26 lb/MMBtu (30-day  N/A.
 MW).                                                                                 be completed 12/31/    rolling) by 2019;
                                                                                      2021).                 0.07 lb/MMBtu (SCR).
PacifiCorp--Jim Bridger Unit 3 (530  ESP + FGC (completed).  0.030 lb/MMBtu........  LNB + OFA + SCR        0.07 lb/MMBtu (30-day  N/A.
 MW).                                                                                 (completed).           rolling) (SCR).

[[Page 21345]]

 
PacifiCorp--Jim Bridger Unit 4 (530  ESP + FGC (completed).  0.030 lb/MMBtu........  LNB + OFA + SCR        0.07 lb/MMBtu (30-day  N/A.
 MW).                                                                                 (completed).           rolling) (SCR).
FMC--Westvaco Trona Plant Unit NS--  ESP (completed).......  0.05 lb/MMBtu.........  LNB + OFA (completed)  0.35 lb/MMBtu (30-day  N/A.
 1A.                                                                                                         rolling).
FMC--Westvaco Trona Plant Unit NS--  ESP (completed).......  0.05 lb/MMBtu.........  LNB + OFA (completed)  0.35 lb/MMBtu (30-day  N/A.
 1B.                                                                                                         rolling).
TATA Chemicals Green River Trona     ESP (completed).......  0.09 lb/MMBtu.........  LNB + SOFA             0.28 lb/MMBtu (30-day  N/A.
 Plant Unit C.                                                                        (completed).           rolling average).
TATA Chemicals Green River Trona     ESP (completed).......  0.09 lb/MMBtu.........  LNB + SOFA             0.28 lb/MMBtu (30-day  N/A.
 Plant Unit D.                                                                        (completed).           rolling).
--------------------------------------------------------------------------------------------------------------------------------------------------------
* The NOX and SO2 emission limits and controls for Basin Electric Laramie River Units 1--3 reflect implementation plan revisions that became federally
  enforceable on June 19, 2019. 84 FR 22711 (May 20, 2019).
** The EPA's Clean Air Markets Division (CAMD) database indicates the operation of the new low NOX burners and separated overfire air began on May 23,
  2010. Air Markets Program Data, https://ampd.epa.gov/ampd/ (last visited February 10, 2020). PacifiCorp appears to be planning to retire the unit by
  2027.
[Dagger] On September 9, 2014, the United States Court of Appeals for the Tenth Circuit stayed the NOX emission limits for Wyodak Unit 1 in the regional
  haze FIP. The NOX emission limits for Laramie River Station Units 1-3 were also stayed but were later revised as explained above.
[dagger] The PM and NOX emission limits and controls reflect a SIP revision that became federally enforceable on April 22, 2019. 84 FR 10433 (March 21,
  2019).
[dagger][dagger] PacifiCorp, 2019 Integrated Resource Plan (October 2019), https://www.pacificorp.com/content/dam/pcorp/documents/en/pacificorp/energy/integrated-resource-plan/2019_IRP_Volume_I.pdf (last visited February 20, 2020).

    The EPA proposes to find that Wyoming has adequately addressed the 
applicable provisions under 40 CFR 51.309(d)(10)(i)(A) regarding the 
implementation status of control measures because the State's Progress 
Report provides documentation of the implementation of control measures 
within Wyoming, including the BART-eligible sources and reasonable 
progress sources in the State.
2. Summary of Emissions Reductions Achieved
    Wyoming's Progress Report must include a summary of the emissions 
reductions achieved throughout the State through implementation of 
control measures mentioned in 40 CFR 51.309(d)(10)(i)(A). 40 CFR 
51.309(d)(10)(i)(B).
    In its Progress Report, Wyoming presents information on emissions 
reductions achieved from the pollution control strategies discussed 
above. The State provides regional SO2 emissions from 2003 
through 2015 (Table 3) as well as Statewide SO2, 
NOX, ammonia, volatile organic compounds, primary organic 
aerosol, elemental carbon, fine soil, and coarse mass emissions in 2002 
and 2008 (Table 4).

           Table 3--Regional SO2 Emissions and Milestones \18\
------------------------------------------------------------------------
                                Adjusted reported
            Year                  SO2 emissions      Adjusted  regional
                                     (tons)           milestone  (tons)
------------------------------------------------------------------------
2003........................             * 330,679             * 447,383
2004........................             * 337,970             * 448,259
2005........................             * 304,591             * 446,903
2006........................            ** 279,134            ** 420,194
2007........................            ** 273,663            ** 420,637
2008........................            ** 244,189               378,398
2009........................               143,704               234,903
2010........................               131,124               200,722
2011........................               117,976               200,722
2012........................                96,246               200,722
2013........................               101,381               185,795
2014........................                92,533               170,868
2015........................                81,454               155,940
------------------------------------------------------------------------
* Represents the adjusted SO2 emissions/milestone for Arizona, New
  Mexico, Oregon, Utah, Wyoming, and Albuquerque-Bernalillo County.
** Represents the adjusted SO2 emissions/milestone for Arizona, New
  Mexico, Utah, Wyoming, and Albuquerque-Bernalillo County. Figures with
  no asterisk represent the adjusted SO2 emissions/milestone for New
  Mexico, Utah, Wyoming, and Albuquerque-Bernalillo County.

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

    \18\ See Wyoming Progress Report, page 10; see also Western 
Regional Air Partnership, 309 Committee: Documents, https://www.wrapair.org//forums/309/docs.html (last visited March 6, 2020). 
This Table represents the adjusted SO2 emissions/
milestone for New Mexico, Utah, Wyoming, and Albuquerque-Bernalillo 
County. Adjustments to reported emissions are required to allow the 
basis of current emissions estimates to account for changes in 
monitoring and calculation methods.

[[Page 21346]]



Table 4 SO2, NOX, Ammonia, Volatile Organic Compounds, Primary Organic Aerosol, Elemental Carbon, Fine Soil, and
                                           Coarse Mass Emissions \19\
----------------------------------------------------------------------------------------------------------------
                                                                                             Difference between
                                                   2002 Emissions        2008 Emissions         2002 and 2008
                   Pollutant                      [dagger]  (tons/      [Dagger]  (tons/      emissions  (tons/
                                                        year)                 year)            year)/ percent
                                                                                                   change
----------------------------------------------------------------------------------------------------------------
Sulfur Dioxide................................               145,840               112,655           -33,186/-23
Nitrogen Oxides...............................               287,974               230,678           -57,296/-20
Ammonia.......................................                33,032                27,024            -6,007/-18
Volatile Organic Compounds....................               816,904               339,534          -477,370/-58
Primary Organic Aerosol.......................                29,194                25,027            -4,167/-14
Elemental Carbon..............................                 8,066                 6,105            -1,961/-24
Fine Soil.....................................                23,020                55,959           32,940/>100
Coarse Mass...................................               102,660               366,673          264,014/>100
----------------------------------------------------------------------------------------------------------------
[dagger] Plan02d.
[Dagger] WestJump2008.

    The emissions data show that there were decreases in emissions of 
SO2, NOX, ammonia, volatile organic compounds, 
primary organic aerosol, and elemental carbon. Furthermore, regional 
SO2 emissions have been below the milestone every year. 
According to the State, for coarse and fine particulate matter 
categories, the increases (>100%) in emissions between 2002 and 2008 
may be due to enhancements in dust inventory methodology rather than 
changes in actual emissions.\20\
---------------------------------------------------------------------------

    \19\ Wyoming Progress Report, pages 30-37.
    \20\ Wyoming Progress Report, page 29.
---------------------------------------------------------------------------

    The EPA proposes to conclude that Wyoming has adequately summarized 
the emissions reductions achieved throughout the State in its Progress 
Report as required under 40 CFR 51.309(d)(10)(i)(B). In meeting this 
requirement, the EPA does not expect states to quantify emissions 
reductions for measures which have not yet been implemented or for 
which the compliance date has not yet been reached. However, for 
purposes of future progress reports, we recommend that Wyoming include 
additional quantitative details on the reductions of each major 
specific visibility-impairing pollutant and utilize the EPA's Clean Air 
Market Division (CAMD) database, \21\ as appropriate.\22\
---------------------------------------------------------------------------

    \21\ The EPA's Clean Air Markets Division (CAMD) database is 
available at: https://ampd.epa.gov/ampd/.
    \22\ U.S. Environmental Protection Agency, General Principles 
for the 5-Year Regional Haze Progress Reports for the Initial 
Regional Haze State Implementation Plans (Intended to Assist States 
and EPA Regional Offices in the Development and Review of the 
Progress Reports), pages 8-9 (April 2013).
---------------------------------------------------------------------------

3. Visibility Conditions and Changes
    Pursuant to 40 CFR 51.309(d)(10)(i)(C), for each mandatory Class I 
area within the State, Wyoming must assess the following visibility 
conditions and changes, with values for most impaired and least 
impaired days \23\ expressed in terms of five-year averages of these 
annual values:
---------------------------------------------------------------------------

    \23\ The ``most impaired days'' and ``least impaired days'' in 
the Regional Haze Rule refers to the average visibility impairment 
(measured in deciviews) for the 20% of monitored days in a calendar 
year with the highest and lowest amount of visibility impairment, 
respectively, averaged over a five-year period. See 40 CFR 51.301.
---------------------------------------------------------------------------

    i. Assess the current visibility conditions for the most impaired 
and least impaired days.
    ii. Analyze the difference between current visibility conditions 
for the most impaired and least impaired days and baseline visibility 
conditions.
    iii. Evaluate the change in visibility impairment for the most 
impaired and least impaired days over the past five years.
    In its Progress Report, Wyoming provides information on visibility 
conditions for the Class I areas within its borders. There are seven 
Class I areas located in Wyoming: Bridger Wilderness, Fitzpatrick 
Wilderness, Grand Teton National Park, North Absaroka Wilderness, Teton 
Wilderness, Washakie Wilderness and Yellowstone National Park. 
Monitoring and data representing visibility conditions in Wyoming's 
seven Class I areas is based on the three Interagency Monitoring of 
Protected Visual Environments (IMPROVE) monitoring sites located across 
the State (Table 5).

                               Table 5--Wyoming's Class I Areas and IMPROVE Sites
----------------------------------------------------------------------------------------------------------------
            Class I area                                             IMPROVE site
----------------------------------------------------------------------------------------------------------------
Bridger Wilderness..................  Bridger (BRID1).
Fitzpatrick Wilderness..............  Bridger (BRID1).
Grand Teton National Park...........  Yellowstone Lake Maintenance Building (YELL2).
North Absaroka Wilderness...........  North Absaroka (NOAB1).
Teton Wilderness....................  Yellowstone Lake Maintenance Building (YELL2).
Washakie Wilderness.................  North Absaroka (NOAB1).
Yellowstone National Park...........  Yellowstone Lake Maintenance Building (YELL2).
----------------------------------------------------------------------------------------------------------------

    The Progress Report addressed current visibility conditions and the 
difference between current visibility conditions and baseline 
visibility conditions with values for the most impaired (20 percent 
worst days) and least impaired and/or clearest days (20 percent best 
days). Table 6: Visibility Progress in Wyoming's Class I Areas, shows 
the difference between the current period (represented by 2005-2009 
data) and the baseline visibility data (represented by 2000-2004 
data).\24\ The EPA supplemented the data provided by the State by 
including more

[[Page 21347]]

current data (2012-2016) for both the worst 20 percent and best 20 
percent days.\25\ We also supplemented the data provided by the State 
by including visibility data for the baseline period (2000-2004) and 
more current period (2012-2016) using the revised visibility tracking 
metric described in the EPA's December 2018 guidance document.\26\ The 
revised visibility tracking metric selects the 20 percent most 
``impaired'' days (as opposed to haziest days) based only on 
anthropogenic impairment so that days with large impacts from extreme, 
episodic natural events such as fires and dust storms are no longer 
selected. Although this revised visibility tracking metric is 
applicable to the second and future implementation periods for regional 
haze (and therefore not retroactively required for progress reports for 
the first regional haze planning period), the revised tracking metric's 
focus on the days with the highest daily anthropogenic impairment 
shifts focus away from days influenced by fire and dust events, and is 
therefore a more accurate metric for showing visibility progress 
especially for Class I areas heavily impacted by wildfire. This 
supplemental data is shown in square brackets in Table 6. Table 7: 
Visibility Rolling 5-Year Averages in Wyoming's Class I Areas, shows 
the rolling 5-year average visibility from 2000-2014 as well as the 
change from the first 5-year rolling average period (2000-2004) to the 
last 5-year rolling average period (2010-2014).\27\
---------------------------------------------------------------------------

    \24\ Wyoming Progress Report, pages 18-19.
    \25\ Federal Land Manager Environmental Database, Visibility 
Status and Trends Following the Regional Haze Rule Metrics, http://views.cira.colostate.edu/fed/SiteBrowser/Default.aspx?appkey=SBCF_VisSum (last visited February 10, 2020).
    \26\ U.S. Environmental Protection Agency, Technical Guidance on 
Tracking Visibility Progress for the Second Implementation Period of 
the Regional Haze Program (December 20, 2018), https://www.epa.gov/sites/production/files/2018-12/documents/technical_guidance_tracking_visibility_progress.pdf (last visited 
February 10, 2020).
    \27\ Wyoming Progress Report, pages 24-27.

                                                 Table 6--Visibility Progress in Wyoming's Class I Areas
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                         More  current    Difference       Difference
              Class I area                       IMPROVE site          Baseline period  Current period   period  2012-     (current-     (more current-
                                                                           2000-04          2005-09           16           baseline)        baseline)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Deciview
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                     20% Worst Days [20% Most Anthropogenically Impaired Days]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bridger Wilderness......................  BRID1.....................        11.1 [8.0]            10.7      10.8 [6.6]            -0.4       -0.3 [-1.4]
Fitzpatrick Wilderness..................  BRID1.....................        11.1 [8.0]            10.7      10.8 [6.6]            -0.4       -0.3 [-1.4]
Grand Teton National Park...............  YELL2.....................        11.8 [8.3]            11.5      12.3 [7.7]            -0.3        0.5 [-0.6]
North Absaroka Wilderness...............  NOAB1.....................        11.5 [8.8]            11.0      11.3 [7.2]            -0.5       -0.2 [-1.6]
Teton Wilderness........................  YELL2.....................        11.8 [8.3]            11.5      12.3 [7.7]            -0.3        0.5 [-0.6]
Washakie Wilderness.....................  NOAB1.....................        11.5 [8.8]            11.0      11.3 [7.2]            -0.5       -0.2 [-1.6]
Yellowstone National Park...............  YELL2.....................        11.8 [8.3]            11.5      12.3 [7.7]            -0.3        0.5 [-0.6]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                           20% Best Days
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bridger Wilderness......................  BRID1.....................               2.1             1.5             0.8            -0.6              -1.3
Fitzpatrick Wilderness..................  BRID1.....................               2.1             1.5             0.8            -0.6              -1.3
Grand Teton National Park...............  YELL2.....................               2.6             2.0             1.4            -0.6              -1.2
North Absaroka Wilderness...............  NOAB1.....................               2.0             1.2             1.0            -0.8              -1.0
Teton Wilderness........................  YELL2.....................               2.6             2.0             1.4            -0.6              -1.2
Washakie Wilderness.....................  NOAB1.....................               2.0             1.2             1.0            -0.8              -1.0
Yellowstone National Park...............  YELL2.....................               2.6             2.0             1.4            -0.6              -1.2
--------------------------------------------------------------------------------------------------------------------------------------------------------


                                         Table 7--Visibility Rolling 5-Year Averages in Wyoming's Class I Areas
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                 Change
             Class I area                     IMPROVE site         2000-04    2005-09    2006-10    2007-11    2008-12    2009-13    2010-14      from
                                                                                                                                                baseline
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                       Deciview
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         20% Worst Days
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bridger Wilderness....................  BRID1...................       11.1       10.7       10.6       10.0       10.8       10.2       10.3       -0.8
Fitzpatrick Wilderness................  BRID1...................       11.1       10.7       10.6       10.0       10.8       10.2       10.3       -0.8
Grand Teton National Park.............  YELL2...................       11.8       11.5       11.6       11.7       12.5       12.0       12.0        0.2
North Absaroka Wilderness.............  NOAB1...................       11.4       11.0        *--        *--        *--        *--       11.6        0.2
Teton Wilderness......................  YELL2...................       11.8       11.5       11.6       11.7       12.5       12.0       12.0        0.2
Washakie Wilderness...................  NOAB1...................       11.4       11.0        *--        *--        *--        *--       11.6        0.2
Yellowstone National Park.............  YELL2...................       11.8       11.5       11.6       11.7       12.5       12.0       12.0        0.2
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                          20% Best Days
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bridger Wilderness....................  BRID1...................        2.1        1.5        1.4        1.3        1.1        1.0        1.0       -1.1
Fitzpatrick Wilderness................  BRID1...................        2.1        1.5        1.4        1.3        1.1        1.0        1.0       -1.1
Grand Teton National Park.............  YELL2...................        2.6        2.0        1.8        1.7        1.5        1.5        1.4       -1.2

[[Page 21348]]

 
North Absaroka Wilderness.............  NOAB1...................        2.0        1.2        *--        *--        *--        *--        1.2       -0.8
Teton Wilderness......................  YELL2...................        2.6        2.0        1.8        1.7        1.5        1.5        1.4       -1.2
Washakie Wilderness...................  NOAB1...................        2.0        1.2        *--        *--        *--        *--        1.2       -0.8
Yellowstone National Park.............  YELL2...................        2.6        2.0        1.8        1.7        1.5        1.5        1.4       -1.2
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Data recovery issues in 2007, 2009, 2010 and 2011 nullified 5-year averages.

    As shown in Table 6, all the IMPROVE monitoring sites within the 
State show improvement in visibility conditions between the baseline 
(2000-2004) and current (2005-2009) periods on both the 20 percent 
worst visibility and 20 percent best visibility days. When considering 
only anthropogenic impairment within the baseline (2000-2004) and most 
current (2012-2016) periods, all of the IMPROVE monitoring sites within 
the State also show improvement in visibility on the 20 percent most 
impaired days. Deciview improvement was consistent over the 2000-2014 
time period, using 5-year rolling averages, on the 20 percent best days 
(Table 7).\28\
---------------------------------------------------------------------------

    \28\ Refer to the Wyoming Progress Report for pollutant 
contributions at each Class I area and 5-year rolling averages. 
Wyoming Progress Report, pages 24-27.
---------------------------------------------------------------------------

    In its Progress Report, Wyoming demonstrates that particulate 
organic matter was the largest contributor to light extinction on the 
20 percent worst days.\29\ According to the State, the largest 
contributions of particulate organic matter generally occurred between 
June and September consistent with the period for increased wildfire 
activity, especially for the year 2012, when wildfires burned nearly 
130,000 acres in June 2012 in Wyoming.\30\ Indeed, when uncontrollable, 
non-anthropogenic sources are removed from the selection of most of the 
worst visibility days, visibility improves by almost 40 percent at all 
Class I areas thereby demonstrating the significant contributions of 
non-anthropogenic sources on visibility, particularly organic mass from 
wildfires.
---------------------------------------------------------------------------

    \29\ Wyoming Progress Report, page 15.
    \30\ NOAA National Centers for Environmental Information, State 
of the Climate: Wildfires for June 2012, http://www.ncdc.noaa.gov/sotc/fire/201206 (last visited February 10, 2020).
---------------------------------------------------------------------------

    The EPA proposes to conclude that Wyoming has adequately addressed 
the requirements under 40 CFR 51.309(d)(10)(i)(C) to include summaries 
of monitored visibility data as required by the Regional Haze Rule.
4. Emissions Tracking Analysis
    Wyoming's Progress Report must include an analysis tracking the 
change over the past five years in emissions of pollutants contributing 
to visibility impairment from all sources and activities within the 
State. 40 CFR 51.309(d)(10)(i)(D).
    In its Progress Report, Wyoming presents data from a 2008 emissions 
inventory, which leverages inventory development work performed by the 
Western Regional Air Partnership (WRAP) for the West-wide Jumpstart Air 
Quality Modeling Study (WestJumpAQMS) \31\ and the Deterministic & 
Empirical Assessment of Smoke's Contribution to Ozone 
(DEASCO3) modeling projects, termed WestJump2008, and 
compares it to the baseline emissions inventory for 2002 (Plan02d). The 
pollutants inventoried include the following source classifications: 
SO2, NOX, ammonia, volatile organic compounds, 
primary organic aerosol, elemental carbon, fine soil and coarse mass 
from both anthropogenic and natural sources (Table 8).
---------------------------------------------------------------------------

    \31\ WRAP Regional Technical Center and West Jump AQMS, https://www.wrapair2.org/WestJumpAQMS.aspx (last visited February 10, 2020). 
Additional information on the WestJump study available in the docket 
for this action, ``WestJump Fact Sheet.''

                                     Table 8--Emissions Progress in Wyoming
                                                   [tons/year]
----------------------------------------------------------------------------------------------------------------
   Pollutant  (anthropogenic,  natural,  and       2002 emissions        2008 emissions     Difference  (percent
                total  sources)                       (Plan02d)          (WestJump2008)            change)
----------------------------------------------------------------------------------------------------------------
SO2:
    Anthropogenic.............................               143,554               111,604         -31,950 (-22)
    Natural...................................                 2,286                 1,051          -1,235 (-54)
                                               -----------------------------------------------------------------
        Total.................................               145,840               112,655         -33,186 (-23)
                                               -----------------------------------------------------------------
NOX:
    Anthropogenic.............................               263,677               216,321         -47,356 (-18)
    Natural...................................                24,297                14,357          -9,940 (-41)
                                               -----------------------------------------------------------------
        Total.................................               287,974               230,678         -57,296 (-20)
                                               -----------------------------------------------------------------
Ammonia:
    Anthropogenic.............................                31,257                21,848          -9,409 (-30)

[[Page 21349]]

 
    Natural...................................                 1,775                 5,177          3,402 (>100)
                                               -----------------------------------------------------------------
        Total.................................                33,032                27,024          -6,007 (-18)
                                               -----------------------------------------------------------------
Volatile Organic Compounds:
    Anthropogenic.............................               193,158               157,134         -36,024 (-19)
    Natural...................................               623,747               182,401        -441,346 (-71)
                                               -----------------------------------------------------------------
        Total.................................               816,904               339,534        -477,370 (-58)
                                               -----------------------------------------------------------------
Primary Organic Aerosol:
    Anthropogenic.............................                 5,401                 8,686            3,285 (61)
    Natural...................................                23,793                16,341          -7,452 (-31)
                                               -----------------------------------------------------------------
        Total.................................                29,194                25,027          -4,167 (-14)
                                               -----------------------------------------------------------------
Elemental Carbon:
    Anthropogenic.............................                 3,144                 3,772              628 (20)
    Natural...................................                 4,922                 2,333          -2,589 (-53)
                                               -----------------------------------------------------------------
        Total.................................                 8,066                 6,105          -1,961 (-24)
                                               -----------------------------------------------------------------
Fine Soil:
    Anthropogenic.............................                15,646                44,382         28,736 (>100)
    Natural...................................                 7,374                11,577            4,204 (57)
                                               -----------------------------------------------------------------
        Total.................................                23,020                55,959         32,940 (>100)
                                               -----------------------------------------------------------------
Coarse Mass:
    Anthropogenic.............................                44,745               312,867        268,122 (>100)
    Natural...................................                57,915                53,806           -4,108 (-7)
                                               -----------------------------------------------------------------
        Total.................................               102,660               366,673        264,014 (>100)
----------------------------------------------------------------------------------------------------------------

    Overall, Wyoming's emissions that affect visibility were reduced in 
all sectors for all pollutants (total) except for coarse and fine 
particulate matter categories. Wyoming cites increases in windblown and 
fugitive dust and enhancements in dust inventory methodologies as 
reasons for the increase in fine and coarse particulate matter 
emissions over the time period analyzed in the Progress Report.\32\ A 
state adjacent to Wyoming, Montana, with similar increases in fine and 
coarse particulate matter also cited larger-than-expected amounts of 
emissions in anthropogenic and natural fires as another reason for the 
increase in fine and coarse particulate matter.\33\ The largest 
differences in point source inventories were decreases in 
SO2 emissions, which can be attributed to the implementation 
of the SO2 Backstop Trading Program in December 2003.
---------------------------------------------------------------------------

    \32\ Wyoming Progress Report, page 29.
    \33\ 84 FR 32682 (July 9, 2019).
---------------------------------------------------------------------------

    The EPA proposes to conclude that Wyoming has adequately addressed 
the requirements under 40 CFR 51.309(d)(10)(i)(D) to track changes in 
emissions of pollutants contributing to visibility impairment from all 
sources and activities within the State.
5. Assessment of Changes Impeding Visibility Progress
    Wyoming's Progress Report must include an assessment of any 
significant changes in anthropogenic emissions within or outside the 
State that have occurred over the past five years that have limited or 
impeded progress in reducing pollutant emissions and improving 
visibility in Class I areas impacted by the State's sources. 40 CFR 
51.309(d)(10)(i)(E).
    In its Progress Report, Wyoming provided an assessment of any 
significant changes in anthropogenic emissions within or outside the 
State. On the 20% worst days over the 5-year period from 2005-2009, 
particulate organic matter and SO2 were the two highest 
contributors to haze in Class I areas in Wyoming.\34\ According to the 
State, the primary sources of anthropogenic particulate organic matter 
in Wyoming include prescribed forest and agricultural burning, vehicle 
exhaust, vehicle refueling, solvent evaporation (e.g. paints), food 
cooking, and various commercial and industrial sources. The primary 
anthropogenic sources of SO2 include coal-burning power 
plants and other industrial sources. In their Progress Report, the 
State concludes that both particulate organic matter and SO2 
are covered by existing regional haze long-term control strategies, 
including the SO2 Backstop Trading Program and other control 
strategies discussed in Section III.A.1. Furthermore, the State 
concludes that there do not appear to be any other anthropogenic 
emissions within Wyoming that would have limited or impeded progress in 
reducing pollutant emissions or improving visibility.
---------------------------------------------------------------------------

    \34\ Wyoming Progress Report, page 16.
---------------------------------------------------------------------------

    Although not cited in Wyoming's Progress Report, at the time of the 
analysis done by the State for the Progress Report, not all BART and 
reasonable progress controls had been installed because compliance 
dates had

[[Page 21350]]

not yet occurred for all facilities subject to BART and reasonable 
progress requirements at that time (Table 2). Thus, the impacts of the 
emissions reductions from those additional controls have not been fully 
realized and are therefore not evident or accounted for in the State's 
Progress Report. Once realized, we anticipate that these additional 
anthropogenic emissions reductions will further improve visibility in 
Wyoming's Class I areas.
    The EPA proposes to find that Wyoming has adequately addressed the 
requirements under 40 CFR 51.309(d)(10)(i)(E) to assess significant 
changes in anthropogenic emissions of visibility impairing pollutants.
6. Assessment of Current Implementation Plan Elements and Strategies
    Wyoming's Progress Report must include an assessment of whether the 
current regional haze implementation plan elements and strategies are 
sufficient to enable the State, or other states with mandatory Class I 
areas affected by emissions from the State, to meet all established 
reasonable progress goals. 40 CFR 51.309(d)(10)(i)(F).
    In its Progress Report, Wyoming provided an assessment of whether 
the current regional haze implementation plan elements and strategies 
are sufficient to enable the State, and other states with Class I areas 
affected by emissions from the State, to meet the reasonable progress 
goals established by the State. However, the EPA disapproved Wyoming's 
reasonable progress goals, and instead promulgated reasonable progress 
goals consistent with the emission limits finalized in the approved SIP 
and FIP.\35\ Due to time and resource constraints, the EPA did not re-
run the modeling necessary to quantify reasonable progress goals in 
deciviews, but anticipated that additional controls imposed by the FIP 
would result in visibility improvement on the 20% worst days.\36\ Thus, 
for the purpose of evaluating this section of the progress report 
requirements, we propose to rely on the fact that all controls required 
by the regional haze implementation plan or modified by subsequent 
action have been installed or are on track to be complete by the 
relevant compliance date, except those stayed by litigation. We also 
propose to rely on other quantitative and qualitative metrics to assess 
the current implementation plan elements and strategies.
---------------------------------------------------------------------------

    \35\ 79 FR 5038 (January 30, 2014).
    \36\ 77 FR 33022, 33057 (June 4, 2012).
---------------------------------------------------------------------------

    Wyoming asserts that even with wildfire emissions included in the 
assessment of visibility impacts on Class I areas, visibility continues 
to improve at the State's Class I areas from 2000 through 2009 and into 
2010. Indeed, key visibility metrics described previously, show: (1) A 
decrease in SO2 and NOX emissions, which are 
associated with anthropogenic sources; (2) improvement in visibility 
conditions between the baseline (2000-2004) and current (2005-2009) 
periods on both the 20 percent worst visibility and 20 percent best 
visibility days; and (3) improvement in visibility conditions at all of 
the IMPROVE monitoring sites within the State on the 20 percent most 
impaired days. Furthermore, the State claims that conservative 
emissions estimates provided in its Progress Report show total 
emissions decreases for all major pollutant categories except coarse 
and fine particulate matter, which are likely due to enhancements in 
inventory methodology.\37\ Wyoming also expects further reductions in 
anthropogenic pollutant categories from a revised regional emissions 
inventory reflective of all final BART and reasonable progress 
controls.\38\
---------------------------------------------------------------------------

    \37\ Wyoming Progress Report, pages 27-29.
    \38\ Wyoming Progress Report, page 41.
---------------------------------------------------------------------------

    Following the future implementation of remaining BART controls and 
the adjustment of the visibility metrics to account only for 
anthropogenic impairment, even greater visibility progress should be 
realized. Thus, Wyoming is confident that the current implementation 
plan elements and strategies are sufficient to make progress towards 
visibility goals and will not impede Class I areas outside of Wyoming 
from meeting their goals in the next planning period.\39\
---------------------------------------------------------------------------

    \39\ Wyoming Progress Report, page 41.
---------------------------------------------------------------------------

    The EPA proposes to conclude that Wyoming has adequately addressed 
the requirements under 40 CFR 51.309(d)(10)(i)(F) and proposes to agree 
with the State's determination that implementation plan elements are 
sufficient to enable the State and other states affected by emissions 
from Wyoming to make progress towards the current reasonable progress 
goals. The EPA views the requirement of this section as a qualitative 
assessment that should evaluate emissions and visibility trends, 
including expected emissions reductions from measures that have not yet 
been implemented.
7. Review of Current Monitoring Strategy
    Wyoming's Progress Report must include a review of the State's 
visibility monitoring strategy and any modifications to the strategy as 
necessary. 40 CFR 51.309(d)(10)(i)(G).
    The monitoring strategy for regional haze in Wyoming relies upon 
participation in the IMPROVE network, which is the primary monitoring 
network for regional haze nationwide.
    In its Progress Report, Wyoming summarizes the existing monitoring 
network, which includes three IMPROVE monitors, used to monitor 
visibility at the seven Class I areas in the State. The State relies 
solely on the IMPROVE monitoring network to track long-term visibility 
improvement and degradation and will continue to rely on the IMPROVE 
monitoring network, without modifications to the existing network, for 
complying with the regional haze monitoring requirements.
    The EPA proposes to find that Wyoming adequately addressed the 
requirements of 40 CFR 51.309(d)(10)(i)(G) because the State reviewed 
its visibility monitoring strategy and determined that no further 
modifications to the strategy are necessary.

B. Determination of Adequacy of the Existing Regional Haze Plan

    The provisions under 40 CFR 51.309(d)(10)(ii) require states to 
determine the adequacy of their existing implementation plan to meet 
existing reasonable progress goals and take one of the following 
actions:
    (1) Submit a negative declaration to the EPA that no further 
substantive revision to the state's existing regional haze 
implementation plan is needed at this time.
    (2) If the state determines that the implementation plan is or may 
be inadequate to ensure reasonable progress due to emissions from 
sources in another state(s) which participated in a regional planning 
process, the state must provide notification to the EPA and to the 
other state(s) which participated in the regional planning process with 
the state. The state must also collaborate with the other state(s) 
through the regional planning process for developing additional 
strategies to address the plan's deficiencies.
    (3) Where the state determines that the implementation plan is or 
may be inadequate to ensure reasonable progress due to emissions from 
sources in another country, the state shall provide notification, along 
with available information, to the Administrator.

[[Page 21351]]

    (4) If the state determines that the implementation plan is or may 
be inadequate to ensure reasonable progress due to emissions from 
sources within the state, then the state shall revise its 
implementation plan to address the plan's deficiencies within one year.
    According to Wyoming, the IMPROVE data demonstrate that Wyoming is 
on track to either meet or exceed the State's reasonable progress 
goals. Thus, Wyoming's Progress Report provides a negative declaration 
to the EPA that no further substantive revisions to the regional haze 
implementation plan are needed to improve visibility in Class I areas 
beyond those controls already in place and scheduled to be installed in 
the future. The EPA proposes to conclude that Wyoming has adequately 
addressed 40 CFR 51.309(d)(10)(i)(G) because: (1) All controls required 
by the regional haze implementation plan or modified by subsequent 
action have been installed or are on track to be complete by the 
relevant compliance date, except those stayed by litigation; and (2) 
key visibility metrics described previously show a decrease in 
SO2 and NOX emissions, improvement in visibility 
conditions between the baseline (2000-2004) and current (2005-2009) 
periods on both the 20 percent worst visibility and 20 percent best 
visibility days, and improvement in visibility conditions at all of the 
IMPROVE monitoring sites within the State on the 20 percent most 
impaired days. Additionally, the EPA expects further visibility 
improvement to result from the future installation of controls required 
by the regional haze implementation plans and subsequent actions.

IV. Proposed Action

    The EPA is proposing to approve Wyoming's November 28, 2017, 
Regional Haze Progress Report as meeting the applicable regional haze 
requirements set forth in 40 CFR 51.309(d)(10).

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 Act and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, the EPA's role is to approve state choices, 
provided that they meet the criteria of the CAA. Accordingly, this 
action merely proposes to approve state law as meeting Federal 
requirements and does not impose additional requirements beyond those 
imposed by state law. For that reason, this action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 
2011);
     Is not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory action because 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 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 application of those requirements would be inconsistent 
with the CAA; and
     Does not provide the EPA with the discretionary authority 
to address, as appropriate, disproportionate human health or 
environmental effects, using practicable and legally permissible 
methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, the SIP is not approved to apply on any Indian 
reservation land or in any other area where the EPA or an Indian tribe 
has demonstrated that a tribe has jurisdiction. In those areas of 
Indian country, the proposed rule does not have tribal implications and 
will not impose substantial direct costs on tribal governments or 
preempt tribal law as specified by Executive Order 13175 (65 FR 67249, 
November 9, 2000).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Carbon monoxide, 
Greenhouse gases, Incorporation by reference, Intergovernmental 
relations, Lead, Nitrogen dioxide, Ozone, Particulate matter, Reporting 
and recordkeeping requirements, Sulfur oxides, Volatile organic 
compounds.

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

    Dated: April 9, 2020.
Gregory Sopkin,
Regional Administrator, EPA Region 8.
[FR Doc. 2020-07941 Filed 4-16-20; 8:45 am]
 BILLING CODE 6560-50-P


