83_FR_18324 83 FR 18243 - Approval and Promulgation of Air Quality Implementation Plans; Colorado; Regional Haze State Implementation Plan

83 FR 18243 - Approval and Promulgation of Air Quality Implementation Plans; Colorado; Regional Haze State Implementation Plan

ENVIRONMENTAL PROTECTION AGENCY

Federal Register Volume 83, Issue 81 (April 26, 2018)

Page Range18243-18248
FR Document2018-08622

The Environmental Protection Agency (EPA) is proposing to approve a State Implementation Plan (SIP) revision submitted by the State of Colorado on May 26, 2017, addressing regional haze. The EPA is proposing to approve source-specific revisions to the nitrogen oxides (NO<INF>X</INF>) best available retrofit technology (BART) determination for Craig Station Unit 1. This unit is owned in part and operated by Tri-State Generation & Transmission Association, Inc. (Tri- State). We are also proposing to approve revisions to the NO<INF>X</INF> reasonable progress determination for Tri-State's Nucla Station. The EPA is taking this action pursuant to section 110 of the Clean Air Act (CAA).

Federal Register, Volume 83 Issue 81 (Thursday, April 26, 2018)
[Federal Register Volume 83, Number 81 (Thursday, April 26, 2018)]
[Proposed Rules]
[Pages 18243-18248]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2018-08622]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R08-OAR-2018-0015; FRL-9976-45--Region 8]


Approval and Promulgation of Air Quality Implementation Plans; 
Colorado; Regional Haze State Implementation Plan

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve a State Implementation Plan (SIP) revision submitted by the 
State of Colorado on May 26, 2017, addressing regional haze. The EPA is 
proposing to approve source-specific revisions to the nitrogen oxides 
(NOX) best available retrofit technology (BART) 
determination for Craig Station Unit 1. This unit is owned in part and 
operated by Tri-State Generation & Transmission Association, Inc. (Tri-
State). We are also proposing to approve revisions to the 
NOX reasonable progress determination for Tri-State's Nucla 
Station. The EPA is taking this action pursuant to section 110 of the 
Clean Air Act (CAA).

DATES: Comments: Written comments must be received on or before May 29, 
2018.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R08-
OAR-2018-0015, 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 Program, 
Environmental Protection Agency (EPA), Region 8, 1595 Wynkoop Street, 
Denver, Colorado 80202-1129. The EPA requests that if at all possible, 
you contact the individual listed in the FOR FURTHER INFORMATION 
CONTACT section to view the hard copy of the docket. You may view the 
hard copy of the docket Monday through Friday, 8:00 a.m. to 4:00 p.m., 
excluding federal holidays.

FOR FURTHER INFORMATION CONTACT: Jaslyn Dobrahner, Air Program, EPA, 
Region 8, Mailcode 8P-AR, 1595 Wynkoop Street, Denver, Colorado, 80202-
1129, (303) 312-6252, dobrahner.jaslyn@epa.gov.

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

Table of Contents

I. What action is the EPA taking?
II. Background
    A. Requirements of the Clean Air Act and the EPA's Regional Haze 
Rule
    B. Best Available Retrofit Technology (BART)
    C. Reasonable Progress Requirements
    D. Consultation With Federal Land Managers (FLMs)
    E. Regulatory and Legal History of the 2012 Colorado SIP
III. Craig Unit 1--NOX BART
    A. Background
    B. May 26, 2017 Submittal
    C. The EPA's Evaluation of Craig Unit 1 Amendments
IV. Nucla--NOX Reasonable Progress
    A. Background
    B. May 26, 2017 Submittal
    C. The EPA's Evaluation of Nucla Amendments
V. Coordination With FLMs
VI. The EPA's Proposed Action
    VII. Incorporation by Reference
VIII. Statutory and Executive Order Reviews

I. What action is the EPA taking?

    On December 31, 2012, the EPA approved a regional haze SIP revision 
submitted by the State of Colorado on May 25, 2011. The 2011 SIP 
revision included NOX BART emission limits for Craig Station 
Units 1 and 2 near Craig, Colorado, and a NOX reasonable 
progress emission limit for the Nucla Station located in Montrose 
County.\1\ The State of Colorado submitted proposed revisions to the 
2011 SIP submittal on May 26, 2017, that modify the NOX BART 
determination for Craig Unit 1 and the NOX reasonable 
progress determination for Nucla. The EPA is now proposing to approve 
those revisions. Specifically, the EPA is proposing to approve the 
State's revisions to the Craig Unit 1 NOX BART determination 
that would require Craig Unit 1 to meet an annual NOX 
emission limit of 4,065 tons per year (tpy) by December 31, 2019. The 
SIP revision would also require the unit to either (1) convert to 
natural gas by August 31, 2023, and if converting to natural gas,

[[Page 18244]]

comply with a NOX emission limit of 0.07 lb/MMBtu (30-day 
rolling average) beginning August 31, 2021, or (2) shut down by 
December 31, 2025. The EPA is also proposing to approve the State's 
revisions to the Nucla NOX reasonable progress determination 
that would require the source to meet an annual NOX emission 
limit of 952 tpy by January 1, 2020, and shut down on or before 
December 31, 2022.
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    \1\ 77 FR 76871 (December 31, 2012).
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II. Background

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

    In section 169A of the CAA, added by the 1977 Amendments to the 
Act, Congress created a program for protecting visibility in the 
nation's national parks and wilderness areas. This section 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.'' \2\ On 
December 2, 1980, the EPA promulgated regulations to address visibility 
impairment in Class I areas that is ``reasonably attributable'' to a 
single source or small group of sources.\3\ These regulations 
represented the first phase in addressing visibility impairment. The 
EPA deferred action on regional haze, which emanates from a variety of 
sources, until monitoring, modeling and scientific knowledge about the 
relationships between pollutants and visibility impairment were 
improved.\4\
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    \2\ 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 which they consider to have 
visibility as 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.''
    \3\ 45 FR 80084, 80084 (December 2, 1980).
    \4\ Regional haze means visibility impairment that is caused by 
the emission of air pollutants from numerous anthropogenic sources 
located over a wide geographic area. Such sources include, but are 
not limited to, major and minor stationary sources, mobile sources, 
and area sources. 40 CFR 51.301.
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    Congress added section 169B to the CAA in 1990 to address regional 
haze issues. The EPA promulgated a rule to address regional haze on 
July 1, 1999.\5\ The Regional Haze Rule (RHR) revised the existing 
visibility regulations 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 
51.309, are included in the EPA's visibility protection regulations at 
40 CFR 51.300-51.309. The EPA revised the RHR on January 10, 2017.\6\
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    \5\ 64 FR 35714, 35714 (July 1, 1999) (codified at 40 CFR part 
51, subpart P).
    \6\ 82 FR 3078 (January 10, 2017).
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    The CAA requires each state to develop a SIP to meet various air 
quality requirements, including protection of visibility.\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 
approved, a SIP is enforceable by the EPA and citizens under the CAA; 
that is, the SIP is federally enforceable.
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    \7\ CAA sections 110(a), 169A, and 169B, 42 U.S.C. 7410(a), 
7491, and 7492(a).
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B. Best Available Retrofit Technology (BART)

    Section 169A of the CAA directs the EPA to require states to 
evaluate the use of retrofit controls at certain larger, often 
uncontrolled, older stationary sources in order to address visibility 
impacts from these sources. Specifically, section 169A(b)(2)(A) 
requires states to include in their SIPs such measures as may be 
necessary to make reasonable progress toward the natural visibility 
goal, including a requirement that certain categories of existing major 
stationary sources built between 1962 and 1977 procure, install, and 
operate the ``Best Available Retrofit Technology'' as determined by the 
states. Under the RHR, states are directed to conduct BART 
determinations for such ``BART-eligible'' sources that may reasonably 
be anticipated to cause or contribute to any visibility impairment in a 
Class I area.
    On July 6, 2005, the EPA published the Guidelines for BART 
Determinations under the Regional Haze Rule (the ``BART Guidelines'') 
to assist states in determining which sources should be subject to the 
BART requirements and in setting appropriate emission limits for each 
covered source.\8\ The process of establishing BART emission 
limitations follows three steps: first, identify the sources that meet 
the definition of ``BART-eligible source'' set forth in 40 CFR 51.301; 
\9\ second, determine which of these sources ``emits any air pollutant 
which may reasonably be anticipated to cause or contribute to any 
impairment of visibility in any such area'' (a source which fits this 
description is ``subject to BART''); and third, for each source subject 
to BART, identify the best available type and level of control for 
reducing emissions. Section 169A(g)(7) of the CAA requires that states 
consider five factors in making BART determinations: (1) The costs of 
compliance; (2) the energy and non-air quality environmental impacts of 
compliance; (3) any existing pollution control technology in use at the 
source; (4) the remaining useful life of the source; and (5) the degree 
of improvement in visibility which may reasonably be anticipated to 
result from the use of such technology. States must address all 
visibility-impairing pollutants emitted by a source in the BART 
determination process. The most significant visibility-impairing 
pollutants are sulfur dioxide (SO2), NOX, and 
particulate matter (PM).
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    \8\ 70 FR 39104; 40 CFR part 51, appendix Y.
    \9\ BART-eligible sources are those sources that have the 
potential to emit 250 tons or more of a visibility-impairing air 
pollutant, were not in operation before August 7, 1962, but were in 
existence on August 7, 1977, and whose operations fall within one or 
more of 26 specifically listed source categories. 40 CFR 51.301.
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    A SIP addressing regional haze must include source-specific BART 
emission limits and compliance schedules for each source subject to 
BART. In lieu of requiring source-specific BART controls, states have 
the flexibility to adopt alternative measures, as long as the 
alternative provides greater reasonable progress towards natural 
visibility conditions than BART (i.e., the alternative must be ``better 
than BART'').\10\ Once a state has made a BART determination, the BART 
controls must be installed and operated as expeditiously as 
practicable, but no later than 5 years after the date of the EPA's 
approval of the final SIP.\11\ In addition to what is required by the 
RHR, general SIP requirements mandate that the SIP include all 
regulatory requirements related to monitoring, recordkeeping, and 
reporting for the BART emission limitations.\12\
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    \10\ 40 CFR 51.308(e)(2) and (3).
    \11\ CAA section 169A(g)(4), 42 U.S.C. 7491(g)(4); 40 CFR 
51.308(e)(1)(iv).
    \12\ CAA section 110(a), 42 U.S.C. 7410(a); 40 CFR part 51, 
subpart K.
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C. Reasonable Progress Requirements

    In addition to BART requirements, each regional haze SIP must 
contain measures as necessary to make reasonable progress towards the 
national visibility goal. As part of determining what measures are 
necessary to make reasonable progress,

[[Page 18245]]

the SIP must first identify anthropogenic sources of visibility 
impairment that are to be considered in developing the long-term 
strategy for addressing visibility impairment.\13\ States must then 
consider the four statutory reasonable progress factors in selecting 
control measures for inclusion in the long-term strategy--the costs of 
compliance, the time necessary for compliance, the energy and non-air 
quality environmental impacts of compliance, and the remaining useful 
life of potentially affected sources.\14\ Finally, the SIP must 
establish reasonable progress goals (RPGs) for each Class I area within 
the State for the plan implementation period (or ``planning period''), 
based on the measures included in the long-term strategy.\15\ If an RPG 
provides for a slower rate of improvement in visibility than the rate 
needed to attain the national goal by 2064, the SIP must demonstrate, 
based on the four reasonable progress factors, why the rate to attain 
the national goal by 2064 is not reasonable and the RPG is 
reasonable.\16\
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    \13\ 40 CFR 51.308(d)(3)(iv).
    \14\ CAA section 169A(g)(1), 42 U.S.C. 7491(g)(1); 40 CFR 
51.308(d)(1)(i)(A).
    \15\ 40 CFR 51.308(d), (f).
    \16\ 40 CFR 51.308(d)(1)(ii).
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D. Consultation With Federal Land Managers (FLMs)

    The RHR requires that a state consult with FLMs before adopting and 
submitting a required SIP or SIP revision.\17\ States must provide FLMs 
an opportunity for consultation, in person and at least 60 days before 
holding any public hearing on the SIP. This consultation must include 
the opportunity for the FLMs to discuss their assessment of impairment 
of visibility in any Class I area and to offer recommendations on the 
development of the RPGs and on the development and implementation of 
strategies to address visibility impairment. Further, a state must 
include in its SIP a description of how it addressed any comments 
provided by the FLMs. Finally, a SIP must provide procedures for 
continuing consultation between the state and FLMs regarding the 
state's visibility protection program, including development and review 
of SIP revisions and 5-year progress reports, and on the implementation 
of other programs having the potential to contribute to impairment of 
visibility in Class I areas.
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    \17\ 40 CFR 51.308(i).
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E. Regulatory and Legal History of the 2012 Colorado SIP

    On December 31, 2012, the EPA approved a regional haze SIP revision 
submitted by the State of Colorado on May 25, 2011. On February 25, 
2013, the National Parks Conservation Association (NPCA) and Wild Earth 
Guardians (Guardians) filed petitions for review in the U.S. Court of 
Appeals for the Tenth Circuit of the EPA's final approval of the 
Colorado regional haze SIP.\18\ Among other things, Guardians and NPCA 
challenged the NOX BART limit for Craig Unit 1. Tri-State 
and the State of Colorado joined the litigation as intervenors. After 
the court consolidated the cases for review, and after several months 
of court-supervised mediation, the parties reached a settlement under 
which Craig Unit 1 would be subject to a 0.07 lb/MMBtu NOX 
limit, consistent with the installation of selective catalytic 
reduction (SCR) controls, by August 31, 2021.\19\ The settlement 
further required that the EPA ask the Tenth Circuit to vacate the 
previous approval of the Colorado SIP revision relating to Craig Unit 1 
and remand the rule to the agency for further action. The court granted 
the EPA's request on December 22, 2014, and signed an order ending the 
litigation on August 15, 2015.
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    \18\ WildEarth Guardians v. EPA, No. 13-9520 (10th Cir.) and 
National Parks Conservation Association v. EPA, No. 13-9525 (10th 
Cir.).
    \19\ 79 FR 47636 (August 14, 2014).
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    In accordance with the terms of the 2014 settlement, Colorado 
submitted a SIP revision to the EPA in 2015 to revise the Craig Unit 1 
NOX BART determination, emission limit, and associated 
compliance deadline. Specifically, Colorado determined that 
NOX BART for Craig Unit 1 was an emission limit of 0.07 lb/
MMBtu, which was based on the capabilities of SCR, and established an 
associated compliance date of August 31, 2021.
    In 2017, Colorado submitted a regional haze SIP revision to the EPA 
reassessing the NOX limit for the Craig Unit 1. The 
revisions were developed after discussions in 2016 between Tri-State, 
Guardians, NPCA, the State of Colorado, and the EPA, and require one of 
two possible NOX BART compliance paths for Craig Unit 1 to 
either (1) shut down by December 31, 2025, or (2) convert to natural-
gas firing by August 31, 2023. If Craig Unit 1 is converted to natural-
gas firing, the NOX emission limit will be 0.07 lb/MMBtu 
after August 31, 2021 (30-day rolling average). If Craig Unit 1 is shut 
down, the NOX emission limit will be 0.28 lb/MMBtu (30-day 
rolling average) until December 31, 2025. Colorado withdrew the 2015 
SIP revision when it submitted the 2017 SIP revision that is the 
subject of this proposed action.

III. Craig Unit 1--NOX BART

A. Background

    The 2011 regional haze SIP for Colorado established a 
NOX BART emission limit for Craig Units 1 and 2. The Craig 
Station is located in Moffat County, approximately 2.5 miles southwest 
of the town of Craig. This facility is a coal-fired power plant with a 
total net electric generating capacity of 1264 megawatts (MW), 
consisting of three units. Units 1 and 2, which are subject to BART, 
are dry-bottom pulverized coal-fired boilers, each rated at a net 
capacity of 428 MW.
    In the 2011 submittal, Colorado determined that selective non-
catalytic reduction (SNCR) was BART for both Unit 1 and Unit 2, based 
on the cost-effectiveness and visibility improvement associated with 
this level of control. Colorado determined that SCR, a more stringent 
control technology, was not BART because its costs were too high. 
Colorado also determined that SNCR could achieve an emission limit of 
0.27 lb/MMBtu (30-day rolling average) at both Unit 1 and Unit 2. 
Nevertheless, as a BART alternative, Colorado ultimately adopted a more 
stringent emission limit for Unit 2 (0.08 lb/MMBtu, 30-day rolling 
average, based on SCR) and a slightly less stringent limit for Unit 1 
(0.28 lb/MMBtu, 30-day rolling average, based on SNCR). The EPA 
approved Colorado's BART alternative and NOX BART emission 
limits into the SIP on December 31, 2012.\20\
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    \20\ 77 FR 76871 (December 31, 2012).
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B. May 26, 2017 Submittal

    On May 26, 2017, Colorado submitted a SIP revision containing 
amendments to the Colorado Code of Regulations, Regulation Number 3, 
Stationary Source Permitting and Air Pollutant Emission Notice 
Requirements, Part F, Regional Haze Limits--Best Available Retrofit 
Technology (BART) and Reasonable Progress (RP), Section VI, Regional 
Haze Determinations. In assessing BART for Craig Unit 1, Colorado 
determined that, under either a 20- or 30-year remaining useful life, 
NOX BART would be an emission limit of 0.07 lb/MMBtu based 
on the installation of SCR.\21\ Colorado

[[Page 18246]]

then reassessed NOX BART for Craig Unit 1 under the two 
compliance paths associated with the 2016 settlement discussions: A 
shutdown in 2025 or a conversion to natural gas in 2023.\22\ After 
completing this reassessment, Colorado established the following 
amendments:
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    \21\ This limit, consistent with the 2014 settlement, was 
contained in the 2015 SIP submission. As noted previously, the State 
withdrew that submission when it submitted the 2017 SIP revision, 
but the State's justification for the 0.07 lb/MMBtu NOX 
BART limit is retained in the 2017 SIP.
    \22\ Colorado used the term ``reassessment,'' and we interpret 
the term to mean that the state reassessed its previous BART 
determination under the differing future factual scenarios to see 
whether those facts were outcome determinative.
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     Craig Unit 1 will either (1) close on or before December 
31, 2025; or (2) cease burning coal no later than August 31, 2021, with 
the option to convert Unit 1 to natural-gas firing by August 31, 2023;
     In the case of a conversion to natural-gas firing, a 30-
day rolling average NOX emission limit of 0.07 lb/MMBtu (30-
day rolling average) will be effective after August 31, 2021;
     The owner/operator of Craig Unit 1 will notify the State 
in writing on or before February 28, 2021, whether Unit 1 will cease 
operation or convert to natural gas;
     For both scenarios, Craig Unit 1 will be subject to an 
interim NOX emission limit of 0.28 lb/MMBtu (30-day rolling 
average), effective January 1, 2017 (first compliance date January 31, 
2017), until December 31, 2025 if closing or August 31, 2021 if 
converting to natural gas; and
     Craig Unit 1 will be subject to an annual NOX 
emission limit of 4,065 tpy effective December 31, 2019, which will be 
calculated on a calendar year basis beginning in 2020.
    The amendments also excepted Craig Unit 1 from complying with the 
original SIP effective date of January 30, 2013, and associated 
compliance date 5 years later. The Colorado Air Quality Control 
Commission adopted the revisions on December 15, 2016 (effective 
February 14, 2017).
1. Shutdown
    For the shutdown compliance path, the State considered two 
amortization periods to reflect the remaining useful life based on two 
possible projected compliance dates and the shutdown date of December 
31, 2025. The first scenario used an amortization period of 4 years and 
4 months, calculated as the difference between a projected compliance 
date of August 31, 2021, (which would have been required under the 
State's BART determination made in conjunction with the 2014 
settlement) and the December 31, 2025 shutdown date. The associated 
emissions reductions, annualized cost, and cost-effectiveness values 
for SNCR and SCR using the amortization period is shown in Table 1.

                                Table 1--Craig Station Unit 1 NOX Cost Comparison
                                        [4 years, 4 months of operation]
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                                                                     Emissions                         Cost
                       Control technology                            reduction      Annualized     effectiveness
                                                                       (tpy)         cost ($)         ($/ton)
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SNCR............................................................             779       6,172,522           7,928
SCR.............................................................           4,048      64,106,699          15,835
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    The second scenario used an amortization period of 8 years, to 
reflect the difference between the December 31, 2025 shutdown date and 
the December 31, 2017 compliance date that the 2012 SIP revision 
approval established.\23\ The associated emissions reductions, 
annualized costs, and cost-effectiveness values for SNCR and SCR using 
the amortization period of 8 years is shown in Table 2.
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    \23\ The operation period begins in calendar year 2018 (December 
31, 2017). The effective date of the EPA's approval of Colorado's 
regional haze SIP was January 30, 2013. As noted previously, the 
Tenth Circuit vacated the EPA's approval of the Craig portions of 
this SIP on December 22, 2014.

                                Table 2--Craig Station Unit 1 NOX Cost Comparison
                                             [8 years of operation]
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                                                                     Emissions                         Cost
                       Control technology                            reduction      Annualized     effectiveness
                                                                       (tpy)         cost ($)         ($/ton)
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SNCR............................................................             779       4,755,842           6,109
SCR.............................................................           4,048      41,476,535          10,245
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    Under both amortization scenarios, the remaining useful life of 
Craig Unit 1 is shorter than the 20-year amortization period used in 
the 2012 BART determination, which increases the annualized costs and 
cost-effectiveness values of the control technologies.\24\ Based on 
this assessment, the State determined that neither SNCR or SCR is cost-
effective when the remaining useful life is shortened to either 4 years 
and 4 months or 8 years, depending on the scenario selected, as a 
result of the shutdown of Craig Unit 1 on December 31, 2025.
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    \24\ The EPA finalized revisions to the Air Pollution Control 
Cost Manual (Chapters 1 and 2), https://www.epa.gov/economic-and-cost-analysis-air-pollution-regulations/cost-reports-and-guidance-air-pollution, in May 2016; these revisions change the amortization 
period for SCR from 20 years to 30 years. The amortization period 
for SNCR remains at 20 years.
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2. Natural Gas Conversion
    For the natural gas conversion compliance path, Craig Unit 1 will 
cease to burn coal by August 31, 2021, with the option to convert to 
natural-gas firing by August 31, 2023. A 30-day rolling average 
NOX emission limit of no more than 0.07 lb/MMBtu will apply 
after August 31, 2021.

C. The EPA's Evaluation of Craig Unit 1 Amendments

    We are proposing to approve Colorado's BART reassessment for two 
possible compliance scenarios for Craig

[[Page 18247]]

Unit 1: (1) Shutdown or (2) conversion to natural gas.
    As a threshold matter, we agree with the State's assessment that an 
emission limit of 0.07 lb/MMBtu would be NOX BART for Craig 
Unit 1 under either a 20- or 30-year remaining useful life. But we also 
agree with the State that it is appropriate to reassess the 
NOX BART limit under the shutdown and natural gas conversion 
scenarios, either of which would considerably shorten the remaining 
useful life of the existing coal-fired boiler.
    While the RHR does not require states to consider source 
retirements or fuel switching (e.g., from coal to gas) as BART options, 
states are free to do so.\25\ In other states, we have approved state-
adopted requirements for the shutdown of a source or for switching 
fuels, which have usually been negotiated between the source operator 
and the state. We also have approved BART determinations that took into 
account the resulting shorter remaining useful life of the affected 
source.
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    \25\ 40 CFR part 51, appendix Y.
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    We agree with Colorado's BART reassessment for both the shutdown 
and natural gas conversion scenarios. Specifically, we acknowledge and 
agree with the assumptions used to calculate the two different 
amortization periods for the shutdown scenario. In past SIP actions, 
the EPA has measured amortization periods from the projected compliance 
date to the date of retirement. In this instance, the compliance date 
for SCR is August 31, 2021, which would have been required under the 
State's BART determination made in conjunction with the 2014 
settlement, resulting in an amortization period of four years and four 
months as reflected in Colorado's first amortization period scenario 
(Table 1). For SNCR, the projected compliance date would be earlier, 
thus resulting in a longer amortization period, albeit one shorter than 
8 years; the 8-year amortization period is therefore a conservative 
approach that understates the annualized costs of both SCR and SNCR.
    When considering the shortened remaining useful life under either 
amortization scenario associated with Craig Unit 1 shutting down by 
December 31, 2025, the EPA finds Colorado's determination reasonable 
that neither SNCR or SCR is cost effective. Therefore, we are proposing 
to approve Colorado's NOX BART reassessment that if Craig 
Unit 1 shuts down by December 31, 2025, neither SNCR or SCR would be 
BART due to the high cost-effectiveness values associated with a 
shortened remaining useful life. We are also proposing to approve the 
alternative compliance path that allows Craig Unit 1 to convert to 
natural-gas firing by August 31, 2023, and cease burning coal by August 
31, 2021, with an associated NOX BART emission limit of 0.07 
lb/MMBtu (30-day rolling average) on that date, because this emission 
limit is equivalent to the one that the State found would be BART under 
a 20- or 30-year remaining useful life scenario. Accordingly, natural-
gas firing is another means by which NOX BART can be met for 
Craig Unit 1. Finally, we are proposing to approve Colorado's 
requirement that an annual NOX limit of 4,065 tpy will be 
effective on December 31, 2019, for Craig Unit 1 because this 
additional measure would strengthen the SIP as there currently is no 
regional haze annual NOX limit for Unit 1.

IV. Nucla--NOX Reasonable Progress

A. Background

    The Tri-State Nucla Station is located in Montrose County 
approximately 3 miles southeast of the town of Nucla, Colorado. The 
Nucla facility consists of one coal-fired steam-driven electric 
generating unit, Unit 4, with a rated electric generating capacity of 
110 MW (gross).
    In 2006, Tri-State installed a small-scale SNCR system on Unit 4 
that injects anhydrous ammonia to achieve NOX reductions. 
The SNCR system is used when NOX emissions approach 0.4 lb/
MMBtu; rates above this result in mass emissions that approach the 
annual permitted NOX limit of 1,987.9 tpy (12-month rolling 
average). Although Colorado, in its 2011 submittal, determined that 
full-scale SNCR and SCR were technically feasible for reducing 
NOX emissions at Nucla Unit 4, the State determined that 
neither control technology was necessary for reasonable progress based 
on the uncertainty of the control efficiency for SNCR and what Colorado 
determined would likely be excessive costs associated with SCR. 
Instead, Colorado determined that Nucla Unit 4 should meet an emission 
limit of 0.5 lb/MMBtu (30-day rolling average) as expeditiously as 
practicable, but in no event later than December 31, 2017, based on 
consideration of the four reasonable progress factors. The EPA approved 
this emission limit into the SIP on December 31, 2012, as meeting the 
relevant regional haze requirements.

B. May 26, 2017 Submittal

    The May 26, 2017 submittal includes the following amendments to the 
Colorado Code of Regulations, Regulation Number 3, Stationary Source 
Permitting and Air Pollutant Emission Notice Requirements, Part F, 
Regional Haze Limits--Best Available Retrofit Technology (BART) and 
Reasonable Progress (RP), Section VI, Regional Haze Determinations, 
related to Nucla:
     Nucla will close on or before December 31, 2022; and
     Nucla will be subject to an annual NOX emission 
limit of 952 tpy effective January 1, 2020, on a calendar year basis 
beginning in 2020.
    The amendments also removed Nucla's original compliance date of 
December 31, 2017, and the requirement for a proposed compliance 
schedule from Nucla due within 60 days after the EPA's approval of the 
reasonable progress portion of Colorado's regional haze SIP. The 
current NOX emission limit of 0.5 lb/MMBtu (30-day rolling 
average) is not amended.

C. The EPA's Evaluation of Nucla Amendments

    Because the amendments, requiring Nucla to shut down on or before 
December 31, 2022, and meet an annual NOX limit of 952 tpy 
by January 1, 2020, do not alter the previously approved 0.5 lb/MMBtu 
(30-day rolling average) emission limit requirement, the closure of 
Nucla achieves greater NOX emission reductions than the 
relevant portions of the 2012 SIP, (which did not previously include 
any shutdown date). We therefore propose to approve Colorado's revision 
related to Nucla.

V. Coordination With FLMs

    Class I areas in Colorado are managed by either the U.S. Forest 
Service (FS) or the U.S. National Park Service (NPS). As described in 
section II.D of this proposed rule, the Regional Haze Rule grants the 
FLMs a special role in the review of regional haze SIPs. Under 40 CFR 
51.308(i)(2), Colorado was obligated to provide the FS and the NPS with 
an opportunity for consultation in development of the State's proposed 
SIP revisions. Colorado provided the FS and the NPS with access to the 
proposed revisions to Regulation Number 3, Part F on January 12, 
2017.\26\ The FLMs did not provide any comments on the proposed 
revisions.
---------------------------------------------------------------------------

    \26\ Email between Colorado and NPS, January 2017.
---------------------------------------------------------------------------

VI. The EPA's Proposed Action

    In this action, the EPA is proposing to approve SIP amendments to 
Regulation Number 3, Part F, Section VI, shown in Table 3, submitted by 
the State of Colorado on May 26, 2017, addressing the NOX 
BART and reasonable progress

[[Page 18248]]

requirements for Craig Unit 1 and Nucla, respectively.

  Table 3--List of Colorado Amendments That EPA Is Proposing To Approve
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
    Amended Sections in May 26, 2017 Submittal Proposed for Approval
------------------------------------------------------------------------
Regulation Number 3, Part F: VI.A.2 (table); VI.A.3; VI.A.4; VI.B.2
 (table); VI.B.3; VI.B.4; VI.D; VI.E.
------------------------------------------------------------------------

VII. Incorporation by Reference

    In this rule, the EPA is proposing to include in a final EPA rule 
regulatory text that includes incorporation by reference. In accordance 
with requirements of 1 CFR 51.5, the EPA is proposing to incorporate by 
reference the amendments described in section VI. The EPA has made, and 
will continue to make, these materials generally available through 
www.regulations.gov and at the EPA Region 8 Office (please contact the 
person identified in the FOR FURTHER INFORMATION CONTACT section of 
this preamble for more information).

VIII. Statutory and Executive Order Reviews

    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 proposed 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 Clean Air Act; 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 proposed 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 rule does not have tribal implications and will not 
impose substantial direct costs on tribal governments or preempt tribal 
law as specified by Executive Order 13175 (65 FR 67249, November 9, 
2000).

List of Subjects in 40 CFR Part 52

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

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

    Dated: April 16, 2018.
Debra Thomas,
Acting Regional Administrator, Region 8.
[FR Doc. 2018-08622 Filed 4-25-18; 8:45 am]
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                                                                        Federal Register / Vol. 83, No. 81 / Thursday, April 26, 2018 / Proposed Rules                                                18243

                                               Department of Homeland Security Delegation              Colorado on May 26, 2017, addressing                   of the docket. You may view the hard
                                               No. 0170.1.                                             regional haze. The EPA is proposing to                 copy of the docket Monday through
                                               ■ 2. Add § 165.T08–0239 to read as                      approve source-specific revisions to the               Friday, 8:00 a.m. to 4:00 p.m., excluding
                                               follows:                                                nitrogen oxides (NOX) best available                   federal holidays.
                                                                                                       retrofit technology (BART)                             FOR FURTHER INFORMATION CONTACT:
                                               § 165.T08–0239      Safety Zone; Ohio River,            determination for Craig Station Unit 1.                Jaslyn Dobrahner, Air Program, EPA,
                                               Cincinnati, OH.                                         This unit is owned in part and operated                Region 8, Mailcode 8P–AR, 1595
                                                 (a) Location. The following area is a                 by Tri-State Generation & Transmission                 Wynkoop Street, Denver, Colorado,
                                               safety zone: all navigable waters of the                Association, Inc. (Tri-State). We are also             80202–1129, (303) 312–6252,
                                               Tennessee River at mile marker (MM) 23                  proposing to approve revisions to the                  dobrahner.jaslyn@epa.gov.
                                               within a 350-foot radius from fireworks                 NOX reasonable progress determination                  SUPPLEMENTARY INFORMATION:
                                               launch site on the Kentucky Dam                         for Tri-State’s Nucla Station. The EPA is              Throughout this document whenever
                                               Marina break wall in Gilbertsville, KY.                 taking this action pursuant to section                 ‘‘we,’’ ‘‘us,’’ or ‘‘our’’ is used, we mean
                                                  (b) Effective date. This section is                  110 of the Clean Air Act (CAA).                        the EPA.
                                               effective from 6:50 p.m. through 10:10                  DATES: Comments: Written comments
                                               p.m. on June 30, 2018.                                  must be received on or before May 29,                  Table of Contents
                                                  (c) Regulations. (1) In accordance with              2018.                                                  I. What action is the EPA taking?
                                               the general regulations in § 165.23 of                  ADDRESSES: Submit your comments,                       II. Background
                                               this part, entry into this zone is                      identified by Docket ID No. EPA–R08–                      A. Requirements of the Clean Air Act and
                                               prohibited unless authorized by the                                                                                  the EPA’s Regional Haze Rule
                                                                                                       OAR–2018–0015, to the Federal                             B. Best Available Retrofit Technology
                                               Captain of the Port Sector Ohio Valley                  Rulemaking Portal: https://
                                               (COTP) or a designated representative.                                                                               (BART)
                                                                                                       www.regulations.gov. Follow the online                    C. Reasonable Progress Requirements
                                                  (2) Persons or vessels desiring to enter             instructions for submitting comments.                     D. Consultation With Federal Land
                                               into or pass through the zone must                      Once submitted, comments cannot be                           Managers (FLMs)
                                               request permission from the COTP or a                   edited or removed from                                    E. Regulatory and Legal History of the 2012
                                               designated representative. They may be                  www.regulations.gov. The EPA may                             Colorado SIP
                                               contacted on VHF–FM Channel 16 or by                    publish any comment received to its                    III. Craig Unit 1—NOX BART
                                               phone at 1–800–253–7465.                                                                                          A. Background
                                                                                                       public docket. Do not submit                              B. May 26, 2017 Submittal
                                                  (3) If permission is granted, all                    electronically any information you
                                               persons and vessels must transit at their                                                                         C. The EPA’s Evaluation of Craig Unit 1
                                                                                                       consider to be Confidential Business                         Amendments
                                               slowest safe speed and comply with all                  Information (CBI) or other information                 IV. Nucla—NOX Reasonable Progress
                                               lawful directions issued by the COTP or                 whose disclosure is restricted by statute.                A. Background
                                               a designated representative.                            Multimedia submissions (audio, video,                     B. May 26, 2017 Submittal
                                                  (d) Informational broadcasts. The                    etc.) must be accompanied by a written                    C. The EPA’s Evaluation of Nucla
                                               COTP or a designated representative                     comment. The written comment is                              Amendments
                                               will inform the public through                                                                                 V. Coordination With FLMs
                                                                                                       considered the official comment and                    VI. The EPA’s Proposed Action
                                               Broadcast Notice to Mariners (BNMs) of                  should include discussion of all points
                                               the enforcement period for the safety                                                                             VII. Incorporation by Reference
                                                                                                       you wish to make. The EPA will                         VIII. Statutory and Executive Order Reviews
                                               zone as well as the date and time of                    generally not consider comments or
                                               enforcement.                                            comment contents located outside of the                I. What action is the EPA taking?
                                                 Dated: April 18, 2018.                                primary submission (i.e., on the web,                     On December 31, 2012, the EPA
                                               M.B. Zamperini,                                         cloud, or other file sharing system). For              approved a regional haze SIP revision
                                               Captain, U.S. Coast Guard, Captain of the               additional submission methods, the full                submitted by the State of Colorado on
                                               Port Sector Ohio Valley.                                EPA public comment policy,                             May 25, 2011. The 2011 SIP revision
                                               [FR Doc. 2018–08743 Filed 4–25–18; 8:45 am]             information about CBI or multimedia                    included NOX BART emission limits for
                                               BILLING CODE 9110–04–P                                  submissions, and general guidance on                   Craig Station Units 1 and 2 near Craig,
                                                                                                       making effective comments, please visit                Colorado, and a NOX reasonable
                                                                                                       http://www2.epa.gov/dockets/                           progress emission limit for the Nucla
                                               ENVIRONMENTAL PROTECTION                                commenting-epa-dockets.                                Station located in Montrose County.1
                                                                                                          Docket: All documents in the docket                 The State of Colorado submitted
                                               AGENCY
                                                                                                       are listed in the www.regulations.gov                  proposed revisions to the 2011 SIP
                                               40 CFR Part 52                                          index. Although listed in the index,                   submittal on May 26, 2017, that modify
                                                                                                       some information is not publicly                       the NOX BART determination for Craig
                                               [EPA–R08–OAR–2018–0015; FRL–9976–                       available, e.g., CBI or other information              Unit 1 and the NOX reasonable progress
                                               45—Region 8]                                            whose disclosure is restricted by statute.             determination for Nucla. The EPA is
                                                                                                       Certain other material, such as                        now proposing to approve those
                                               Approval and Promulgation of Air
                                                                                                       copyrighted material, will be publicly                 revisions. Specifically, the EPA is
                                               Quality Implementation Plans;
                                                                                                       available only in hard copy. Publicly                  proposing to approve the State’s
                                               Colorado; Regional Haze State
                                                                                                       available docket materials are available               revisions to the Craig Unit 1 NOX BART
                                               Implementation Plan
                                                                                                       either electronically in                               determination that would require Craig
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                                               AGENCY:  Environmental Protection                       www.regulations.gov or in hard copy at                 Unit 1 to meet an annual NOX emission
                                               Agency (EPA).                                           the Air Program, Environmental                         limit of 4,065 tons per year (tpy) by
                                               ACTION: Proposed rule.                                  Protection Agency (EPA), Region 8,                     December 31, 2019. The SIP revision
                                                                                                       1595 Wynkoop Street, Denver, Colorado                  would also require the unit to either (1)
                                               SUMMARY:  The Environmental Protection                  80202–1129. The EPA requests that if at                convert to natural gas by August 31,
                                               Agency (EPA) is proposing to approve a                  all possible, you contact the individual               2023, and if converting to natural gas,
                                               State Implementation Plan (SIP)                         listed in the FOR FURTHER INFORMATION
                                               revision submitted by the State of                      CONTACT section to view the hard copy                   1 77   FR 76871 (December 31, 2012).



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                                               18244                    Federal Register / Vol. 83, No. 81 / Thursday, April 26, 2018 / Proposed Rules

                                               comply with a NOX emission limit of                      address regional haze on July 1, 1999.5               of these sources ‘‘emits any air pollutant
                                               0.07 lb/MMBtu (30-day rolling average)                   The Regional Haze Rule (RHR) revised                  which may reasonably be anticipated to
                                               beginning August 31, 2021, or (2) shut                   the existing visibility regulations to                cause or contribute to any impairment
                                               down by December 31, 2025. The EPA                       integrate provisions addressing regional              of visibility in any such area’’ (a source
                                               is also proposing to approve the State’s                 haze and established a comprehensive                  which fits this description is ‘‘subject to
                                               revisions to the Nucla NOX reasonable                    visibility protection program for Class I             BART’’); and third, for each source
                                               progress determination that would                        areas. The requirements for regional                  subject to BART, identify the best
                                               require the source to meet an annual                     haze, found at 40 CFR 51.308 and                      available type and level of control for
                                               NOX emission limit of 952 tpy by                         51.309, are included in the EPA’s                     reducing emissions. Section 169A(g)(7)
                                               January 1, 2020, and shut down on or                     visibility protection regulations at 40               of the CAA requires that states consider
                                               before December 31, 2022.                                CFR 51.300–51.309. The EPA revised                    five factors in making BART
                                                                                                        the RHR on January 10, 2017.6                         determinations: (1) The costs of
                                               II. Background                                              The CAA requires each state to                     compliance; (2) the energy and non-air
                                               A. Requirements of the Clean Air Act                     develop a SIP to meet various air quality             quality environmental impacts of
                                               and the EPA’s Regional Haze Rule                         requirements, including protection of                 compliance; (3) any existing pollution
                                                                                                        visibility.7 Regional haze SIPs must                  control technology in use at the source;
                                                  In section 169A of the CAA, added by                  assure reasonable progress toward the                 (4) the remaining useful life of the
                                               the 1977 Amendments to the Act,                          national goal of achieving natural                    source; and (5) the degree of
                                               Congress created a program for                           visibility conditions in Class I areas. A             improvement in visibility which may
                                               protecting visibility in the nation’s                    state must submit its SIP and SIP                     reasonably be anticipated to result from
                                               national parks and wilderness areas.                     revisions to the EPA for approval. Once               the use of such technology. States must
                                               This section establishes ‘‘as a national                 approved, a SIP is enforceable by the                 address all visibility-impairing
                                               goal the prevention of any future, and                   EPA and citizens under the CAA; that                  pollutants emitted by a source in the
                                               the remedying of any existing,                           is, the SIP is federally enforceable.                 BART determination process. The most
                                               impairment of visibility in mandatory
                                                                                                        B. Best Available Retrofit Technology                 significant visibility-impairing
                                               Class I Federal areas which impairment
                                                                                                        (BART)                                                pollutants are sulfur dioxide (SO2),
                                               results from manmade air pollution.’’ 2
                                                                                                                                                              NOX, and particulate matter (PM).
                                               On December 2, 1980, the EPA                                Section 169A of the CAA directs the                   A SIP addressing regional haze must
                                               promulgated regulations to address                       EPA to require states to evaluate the use             include source-specific BART emission
                                               visibility impairment in Class I areas                   of retrofit controls at certain larger, often         limits and compliance schedules for
                                               that is ‘‘reasonably attributable’’ to a                 uncontrolled, older stationary sources in
                                                                                                                                                              each source subject to BART. In lieu of
                                               single source or small group of sources.3                order to address visibility impacts from
                                                                                                                                                              requiring source-specific BART
                                               These regulations represented the first                  these sources. Specifically, section
                                                                                                                                                              controls, states have the flexibility to
                                               phase in addressing visibility                           169A(b)(2)(A) requires states to include
                                                                                                                                                              adopt alternative measures, as long as
                                               impairment. The EPA deferred action on                   in their SIPs such measures as may be
                                                                                                                                                              the alternative provides greater
                                               regional haze, which emanates from a                     necessary to make reasonable progress
                                                                                                                                                              reasonable progress towards natural
                                               variety of sources, until monitoring,                    toward the natural visibility goal,
                                                                                                                                                              visibility conditions than BART (i.e., the
                                               modeling and scientific knowledge                        including a requirement that certain
                                                                                                                                                              alternative must be ‘‘better than
                                               about the relationships between                          categories of existing major stationary
                                                                                                                                                              BART’’).10 Once a state has made a
                                               pollutants and visibility impairment                     sources built between 1962 and 1977
                                                                                                                                                              BART determination, the BART controls
                                               were improved.4                                          procure, install, and operate the ‘‘Best
                                                                                                                                                              must be installed and operated as
                                                  Congress added section 169B to the                    Available Retrofit Technology’’ as
                                                                                                                                                              expeditiously as practicable, but no later
                                               CAA in 1990 to address regional haze                     determined by the states. Under the
                                                                                                                                                              than 5 years after the date of the EPA’s
                                               issues. The EPA promulgated a rule to                    RHR, states are directed to conduct
                                                                                                                                                              approval of the final SIP.11 In addition
                                                                                                        BART determinations for such ‘‘BART–
                                                                                                                                                              to what is required by the RHR, general
                                                  2 42 U.S.C. 7491(a). Areas designated as              eligible’’ sources that may reasonably be
                                                                                                                                                              SIP requirements mandate that the SIP
                                               mandatory Class I Federal areas consist of national      anticipated to cause or contribute to any
                                               parks exceeding 6000 acres, wilderness areas and                                                               include all regulatory requirements
                                                                                                        visibility impairment in a Class I area.
                                               national memorial parks exceeding 5000 acres, and           On July 6, 2005, the EPA published                 related to monitoring, recordkeeping,
                                               all international parks that were in existence on
                                                                                                        the Guidelines for BART Determinations                and reporting for the BART emission
                                               August 7, 1977. 42 U.S.C. 7472(a). In accordance                                                               limitations.12
                                               with section 169A of the CAA, EPA, in consultation       under the Regional Haze Rule (the
                                               with the Department of Interior, promulgated a list      ‘‘BART Guidelines’’) to assist states in              C. Reasonable Progress Requirements
                                               of 156 areas where visibility is identified as an        determining which sources should be
                                               important value. 44 FR 69122 (November 30, 1979).                                                                In addition to BART requirements,
                                               The extent of a mandatory Class I area includes          subject to the BART requirements and
                                                                                                                                                              each regional haze SIP must contain
                                               subsequent changes in boundaries, such as park           in setting appropriate emission limits
                                                                                                                                                              measures as necessary to make
                                               expansions. 42 U.S.C. 7472(a). Although states and       for each covered source.8 The process of
                                               tribes may designate as Class I additional areas                                                               reasonable progress towards the
                                                                                                        establishing BART emission limitations
                                               which they consider to have visibility as an                                                                   national visibility goal. As part of
                                               important value, the requirements of the visibility      follows three steps: first, identify the
                                                                                                                                                              determining what measures are
                                               program set forth in section 169A of the CAA apply       sources that meet the definition of
                                                                                                                                                              necessary to make reasonable progress,
                                               only to ‘‘mandatory Class I Federal areas.’’ Each        ‘‘BART-eligible source’’ set forth in 40
                                               mandatory Class I Federal area is the responsibility     CFR 51.301; 9 second, determine which
                                               of a ‘‘Federal Land Manager.’’ 42 U.S.C. 7602(i).                                                              visibility-impairing air pollutant, were not in
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                                               When we use the term ‘‘Class I area’’ in this section,                                                         operation before August 7, 1962, but were in
                                                                                                          5 64 FR 35714, 35714 (July 1, 1999) (codified at
                                               we mean a ‘‘mandatory Class I Federal area.’’                                                                  existence on August 7, 1977, and whose operations
                                                  3 45 FR 80084, 80084 (December 2, 1980).              40 CFR part 51, subpart P).                           fall within one or more of 26 specifically listed
                                                                                                          6 82 FR 3078 (January 10, 2017).                    source categories. 40 CFR 51.301.
                                                  4 Regional haze means visibility impairment that
                                                                                                          7 CAA sections 110(a), 169A, and 169B, 42 U.S.C.       10 40 CFR 51.308(e)(2) and (3).
                                               is caused by the emission of air pollutants from
                                               numerous anthropogenic sources located over a            7410(a), 7491, and 7492(a).                              11 CAA section 169A(g)(4), 42 U.S.C. 7491(g)(4);
                                                                                                          8 70 FR 39104; 40 CFR part 51, appendix Y.          40 CFR 51.308(e)(1)(iv).
                                               wide geographic area. Such sources include, but are
                                               not limited to, major and minor stationary sources,        9 BART-eligible sources are those sources that         12 CAA section 110(a), 42 U.S.C. 7410(a); 40 CFR

                                               mobile sources, and area sources. 40 CFR 51.301.         have the potential to emit 250 tons or more of a      part 51, subpart K.



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                                                                        Federal Register / Vol. 83, No. 81 / Thursday, April 26, 2018 / Proposed Rules                                                      18245

                                               the SIP must first identify                             E. Regulatory and Legal History of the                 December 31, 2025. Colorado withdrew
                                               anthropogenic sources of visibility                     2012 Colorado SIP                                      the 2015 SIP revision when it submitted
                                               impairment that are to be considered in                    On December 31, 2012, the EPA                       the 2017 SIP revision that is the subject
                                               developing the long-term strategy for                   approved a regional haze SIP revision                  of this proposed action.
                                               addressing visibility impairment.13                     submitted by the State of Colorado on                  III. Craig Unit 1—NOX BART
                                               States must then consider the four                      May 25, 2011. On February 25, 2013, the
                                               statutory reasonable progress factors in                National Parks Conservation                            A. Background
                                               selecting control measures for inclusion                Association (NPCA) and Wild Earth                         The 2011 regional haze SIP for
                                               in the long-term strategy—the costs of                  Guardians (Guardians) filed petitions for              Colorado established a NOX BART
                                               compliance, the time necessary for                      review in the U.S. Court of Appeals for                emission limit for Craig Units 1 and 2.
                                               compliance, the energy and non-air                      the Tenth Circuit of the EPA’s final                   The Craig Station is located in Moffat
                                               quality environmental impacts of                        approval of the Colorado regional haze                 County, approximately 2.5 miles
                                               compliance, and the remaining useful                    SIP.18 Among other things, Guardians                   southwest of the town of Craig. This
                                               life of potentially affected sources.14                 and NPCA challenged the NOX BART                       facility is a coal-fired power plant with
                                               Finally, the SIP must establish                         limit for Craig Unit 1. Tri-State and the              a total net electric generating capacity of
                                               reasonable progress goals (RPGs) for                    State of Colorado joined the litigation as             1264 megawatts (MW), consisting of
                                                                                                       intervenors. After the court consolidated              three units. Units 1 and 2, which are
                                               each Class I area within the State for the
                                                                                                       the cases for review, and after several                subject to BART, are dry-bottom
                                               plan implementation period (or
                                                                                                       months of court-supervised mediation,                  pulverized coal-fired boilers, each rated
                                               ‘‘planning period’’), based on the                      the parties reached a settlement under
                                               measures included in the long-term                                                                             at a net capacity of 428 MW.
                                                                                                       which Craig Unit 1 would be subject to                    In the 2011 submittal, Colorado
                                               strategy.15 If an RPG provides for a                    a 0.07 lb/MMBtu NOX limit, consistent
                                               slower rate of improvement in visibility                                                                       determined that selective non-catalytic
                                                                                                       with the installation of selective                     reduction (SNCR) was BART for both
                                               than the rate needed to attain the                      catalytic reduction (SCR) controls, by                 Unit 1 and Unit 2, based on the cost-
                                               national goal by 2064, the SIP must                     August 31, 2021.19 The settlement                      effectiveness and visibility
                                               demonstrate, based on the four                          further required that the EPA ask the                  improvement associated with this level
                                               reasonable progress factors, why the rate               Tenth Circuit to vacate the previous                   of control. Colorado determined that
                                               to attain the national goal by 2064 is not              approval of the Colorado SIP revision                  SCR, a more stringent control
                                               reasonable and the RPG is reasonable.16                 relating to Craig Unit 1 and remand the                technology, was not BART because its
                                                                                                       rule to the agency for further action. The             costs were too high. Colorado also
                                               D. Consultation With Federal Land                       court granted the EPA’s request on
                                               Managers (FLMs)                                                                                                determined that SNCR could achieve an
                                                                                                       December 22, 2014, and signed an order                 emission limit of 0.27 lb/MMBtu (30-
                                                 The RHR requires that a state consult                 ending the litigation on August 15,
                                                                                                                                                              day rolling average) at both Unit 1 and
                                                                                                       2015.
                                               with FLMs before adopting and                                                                                  Unit 2. Nevertheless, as a BART
                                                                                                         In accordance with the terms of the
                                               submitting a required SIP or SIP                        2014 settlement, Colorado submitted a                  alternative, Colorado ultimately adopted
                                               revision.17 States must provide FLMs an                 SIP revision to the EPA in 2015 to revise              a more stringent emission limit for Unit
                                               opportunity for consultation, in person                 the Craig Unit 1 NOX BART                              2 (0.08 lb/MMBtu, 30-day rolling
                                               and at least 60 days before holding any                 determination, emission limit, and                     average, based on SCR) and a slightly
                                               public hearing on the SIP. This                         associated compliance deadline.                        less stringent limit for Unit 1 (0.28 lb/
                                               consultation must include the                           Specifically, Colorado determined that                 MMBtu, 30-day rolling average, based
                                               opportunity for the FLMs to discuss                     NOX BART for Craig Unit 1 was an                       on SNCR). The EPA approved
                                               their assessment of impairment of                       emission limit of 0.07 lb/MMBtu, which                 Colorado’s BART alternative and NOX
                                               visibility in any Class I area and to offer             was based on the capabilities of SCR,                  BART emission limits into the SIP on
                                               recommendations on the development                      and established an associated                          December 31, 2012.20
                                               of the RPGs and on the development                      compliance date of August 31, 2021.                    B. May 26, 2017 Submittal
                                               and implementation of strategies to                        In 2017, Colorado submitted a
                                                                                                       regional haze SIP revision to the EPA                    On May 26, 2017, Colorado submitted
                                               address visibility impairment. Further, a                                                                      a SIP revision containing amendments
                                               state must include in its SIP a                         reassessing the NOX limit for the Craig
                                                                                                       Unit 1. The revisions were developed                   to the Colorado Code of Regulations,
                                               description of how it addressed any                                                                            Regulation Number 3, Stationary Source
                                               comments provided by the FLMs.                          after discussions in 2016 between Tri-
                                                                                                       State, Guardians, NPCA, the State of                   Permitting and Air Pollutant Emission
                                               Finally, a SIP must provide procedures                                                                         Notice Requirements, Part F, Regional
                                               for continuing consultation between the                 Colorado, and the EPA, and require one
                                                                                                       of two possible NOX BART compliance                    Haze Limits—Best Available Retrofit
                                               state and FLMs regarding the state’s                                                                           Technology (BART) and Reasonable
                                                                                                       paths for Craig Unit 1 to either (1) shut
                                               visibility protection program, including                                                                       Progress (RP), Section VI, Regional Haze
                                                                                                       down by December 31, 2025, or (2)
                                               development and review of SIP                           convert to natural-gas firing by August                Determinations. In assessing BART for
                                               revisions and 5-year progress reports,                  31, 2023. If Craig Unit 1 is converted to              Craig Unit 1, Colorado determined that,
                                               and on the implementation of other                      natural-gas firing, the NOX emission                   under either a 20- or 30-year remaining
                                               programs having the potential to                        limit will be 0.07 lb/MMBtu after                      useful life, NOX BART would be an
                                               contribute to impairment of visibility in               August 31, 2021 (30-day rolling                        emission limit of 0.07 lb/MMBtu based
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                                               Class I areas.                                          average). If Craig Unit 1 is shut down,                on the installation of SCR.21 Colorado
                                                                                                       the NOX emission limit will be 0.28 lb/                  20 77
                                                 13 40 CFR 51.308(d)(3)(iv).                                                                                         FR 76871 (December 31, 2012).
                                                                                                       MMBtu (30-day rolling average) until                     21 This limit, consistent with the 2014 settlement,
                                                 14 CAA  section 169A(g)(1), 42 U.S.C. 7491(g)(1);
                                                                                                                                                              was contained in the 2015 SIP submission. As
                                               40 CFR 51.308(d)(1)(i)(A).                                18 WildEarth Guardians v. EPA, No. 13–9520
                                                 15 40 CFR 51.308(d), (f).
                                                                                                                                                              noted previously, the State withdrew that
                                                                                                       (10th Cir.) and National Parks Conservation            submission when it submitted the 2017 SIP
                                                 16 40 CFR 51.308(d)(1)(ii).                           Association v. EPA, No. 13–9525 (10th Cir.).           revision, but the State’s justification for the 0.07 lb/
                                                 17 40 CFR 51.308(i).                                    19 79 FR 47636 (August 14, 2014).                                                                  Continued




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                                               18246                             Federal Register / Vol. 83, No. 81 / Thursday, April 26, 2018 / Proposed Rules

                                               then reassessed NOX BART for Craig                                          1 will cease operation or convert to                                    1. Shutdown
                                               Unit 1 under the two compliance paths                                       natural gas;
                                               associated with the 2016 settlement                                            • For both scenarios, Craig Unit 1 will                                 For the shutdown compliance path,
                                               discussions: A shutdown in 2025 or a                                        be subject to an interim NOX emission                                   the State considered two amortization
                                               conversion to natural gas in 2023.22                                        limit of 0.28 lb/MMBtu (30-day rolling                                  periods to reflect the remaining useful
                                               After completing this reassessment,                                         average), effective January 1, 2017 (first                              life based on two possible projected
                                               Colorado established the following                                          compliance date January 31, 2017), until                                compliance dates and the shutdown
                                               amendments:                                                                 December 31, 2025 if closing or August                                  date of December 31, 2025. The first
                                                  • Craig Unit 1 will either (1) close on                                  31, 2021 if converting to natural gas;                                  scenario used an amortization period of
                                               or before December 31, 2025; or (2)                                         and                                                                     4 years and 4 months, calculated as the
                                               cease burning coal no later than August                                        • Craig Unit 1 will be subject to an                                 difference between a projected
                                               31, 2021, with the option to convert                                        annual NOX emission limit of 4,065 tpy                                  compliance date of August 31, 2021,
                                                                                                                           effective December 31, 2019, which will                                 (which would have been required under
                                               Unit 1 to natural-gas firing by August
                                                                                                                           be calculated on a calendar year basis                                  the State’s BART determination made in
                                               31, 2023;
                                                                                                                           beginning in 2020.
                                                  • In the case of a conversion to                                            The amendments also excepted Craig                                   conjunction with the 2014 settlement)
                                               natural-gas firing, a 30-day rolling                                        Unit 1 from complying with the original                                 and the December 31, 2025 shutdown
                                               average NOX emission limit of 0.07 lb/                                      SIP effective date of January 30, 2013,                                 date. The associated emissions
                                               MMBtu (30-day rolling average) will be                                      and associated compliance date 5 years                                  reductions, annualized cost, and cost-
                                               effective after August 31, 2021;                                            later. The Colorado Air Quality Control                                 effectiveness values for SNCR and SCR
                                                  • The owner/operator of Craig Unit 1                                     Commission adopted the revisions on                                     using the amortization period is shown
                                               will notify the State in writing on or                                      December 15, 2016 (effective February                                   in Table 1.
                                               before February 28, 2021, whether Unit                                      14, 2017).

                                                                                                        TABLE 1—CRAIG STATION UNIT 1 NOX COST COMPARISON
                                                                                                                                      [4 years, 4 months of operation]

                                                                                                                                                                                                   Emissions         Annualized             Cost
                                                                                                        Control technology                                                                         reduction            cost           effectiveness
                                                                                                                                                                                                     (tpy)               ($)               ($/ton)

                                               SNCR ...........................................................................................................................................             779         6,172,522               7,928
                                               SCR .............................................................................................................................................          4,048        64,106,699              15,835



                                                 The second scenario used an                                               31, 2017 compliance date that the 2012                                  values for SNCR and SCR using the
                                               amortization period of 8 years, to reflect                                  SIP revision approval established.23 The                                amortization period of 8 years is shown
                                               the difference between the December 31,                                     associated emissions reductions,                                        in Table 2.
                                               2025 shutdown date and the December                                         annualized costs, and cost-effectiveness

                                                                                                        TABLE 2—CRAIG STATION UNIT 1 NOX COST COMPARISON
                                                                                                                                               [8 years of operation]

                                                                                                                                                                                                   Emissions         Annualized             Cost
                                                                                                        Control technology                                                                         reduction            cost           effectiveness
                                                                                                                                                                                                     (tpy)               ($)               ($/ton)

                                               SNCR ...........................................................................................................................................             779         4,755,842               6,109
                                               SCR .............................................................................................................................................          4,048        41,476,535              10,245



                                                  Under both amortization scenarios,                                       shortened to either 4 years and 4                                       firing by August 31, 2023. A 30-day
                                               the remaining useful life of Craig Unit                                     months or 8 years, depending on the                                     rolling average NOX emission limit of no
                                               1 is shorter than the 20-year                                               scenario selected, as a result of the                                   more than 0.07 lb/MMBtu will apply
                                               amortization period used in the 2012                                        shutdown of Craig Unit 1 on December                                    after August 31, 2021.
                                               BART determination, which increases                                         31, 2025.
                                               the annualized costs and cost-                                                                                                                      C. The EPA’s Evaluation of Craig Unit
                                                                                                                           2. Natural Gas Conversion                                               1 Amendments
                                               effectiveness values of the control
                                               technologies.24 Based on this                                                 For the natural gas conversion                                          We are proposing to approve
                                               assessment, the State determined that                                       compliance path, Craig Unit 1 will cease                                Colorado’s BART reassessment for two
                                               neither SNCR or SCR is cost-effective                                       to burn coal by August 31, 2021, with                                   possible compliance scenarios for Craig
                                               when the remaining useful life is                                           the option to convert to natural-gas
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                                               MMBtu NOX BART limit is retained in the 2017                                  23 The operation period begins in calendar year                       https://www.epa.gov/economic-and-cost-analysis-
                                               SIP.                                                                        2018 (December 31, 2017). The effective date of the                     air-pollution-regulations/cost-reports-and-
                                                  22 Colorado used the term ‘‘reassessment,’’ and we                       EPA’s approval of Colorado’s regional haze SIP was                      guidance-air-pollution, in May 2016; these revisions
                                                                                                                           January 30, 2013. As noted previously, the Tenth                        change the amortization period for SCR from 20
                                               interpret the term to mean that the state reassessed
                                                                                                                           Circuit vacated the EPA’s approval of the Craig
                                               its previous BART determination under the                                                                                                           years to 30 years. The amortization period for SNCR
                                                                                                                           portions of this SIP on December 22, 2014.
                                               differing future factual scenarios to see whether                             24 The EPA finalized revisions to the Air                             remains at 20 years.
                                               those facts were outcome determinative.                                     Pollution Control Cost Manual (Chapters 1 and 2),



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                                                                         Federal Register / Vol. 83, No. 81 / Thursday, April 26, 2018 / Proposed Rules                                                 18247

                                               Unit 1: (1) Shutdown or (2) conversion                    We are also proposing to approve the                   Regulation Number 3, Stationary Source
                                               to natural gas.                                           alternative compliance path that allows                Permitting and Air Pollutant Emission
                                                  As a threshold matter, we agree with                   Craig Unit 1 to convert to natural-gas                 Notice Requirements, Part F, Regional
                                               the State’s assessment that an emission                   firing by August 31, 2023, and cease                   Haze Limits—Best Available Retrofit
                                               limit of 0.07 lb/MMBtu would be NOX                       burning coal by August 31, 2021, with                  Technology (BART) and Reasonable
                                               BART for Craig Unit 1 under either a 20-                  an associated NOX BART emission limit                  Progress (RP), Section VI, Regional Haze
                                               or 30-year remaining useful life. But we                  of 0.07 lb/MMBtu (30-day rolling                       Determinations, related to Nucla:
                                               also agree with the State that it is                      average) on that date, because this                      • Nucla will close on or before
                                               appropriate to reassess the NOX BART                      emission limit is equivalent to the one                December 31, 2022; and
                                               limit under the shutdown and natural                      that the State found would be BART                       • Nucla will be subject to an annual
                                               gas conversion scenarios, either of                       under a 20- or 30-year remaining useful                NOX emission limit of 952 tpy effective
                                               which would considerably shorten the                      life scenario. Accordingly, natural-gas                January 1, 2020, on a calendar year basis
                                               remaining useful life of the existing                     firing is another means by which NOX                   beginning in 2020.
                                               coal-fired boiler.                                        BART can be met for Craig Unit 1.                         The amendments also removed
                                                  While the RHR does not require states                  Finally, we are proposing to approve                   Nucla’s original compliance date of
                                               to consider source retirements or fuel                    Colorado’s requirement that an annual                  December 31, 2017, and the requirement
                                               switching (e.g., from coal to gas) as                     NOX limit of 4,065 tpy will be effective               for a proposed compliance schedule
                                               BART options, states are free to do so.25                 on December 31, 2019, for Craig Unit 1                 from Nucla due within 60 days after the
                                               In other states, we have approved state-                  because this additional measure would                  EPA’s approval of the reasonable
                                               adopted requirements for the shutdown                     strengthen the SIP as there currently is               progress portion of Colorado’s regional
                                               of a source or for switching fuels, which                 no regional haze annual NOX limit for                  haze SIP. The current NOX emission
                                               have usually been negotiated between                      Unit 1.                                                limit of 0.5 lb/MMBtu (30-day rolling
                                               the source operator and the state. We                                                                            average) is not amended.
                                               also have approved BART                                   IV. Nucla—NOX Reasonable Progress
                                               determinations that took into account                                                                            C. The EPA’s Evaluation of Nucla
                                                                                                         A. Background                                          Amendments
                                               the resulting shorter remaining useful
                                               life of the affected source.                                 The Tri-State Nucla Station is located                Because the amendments, requiring
                                                  We agree with Colorado’s BART                          in Montrose County approximately 3                     Nucla to shut down on or before
                                               reassessment for both the shutdown and                    miles southeast of the town of Nucla,                  December 31, 2022, and meet an annual
                                               natural gas conversion scenarios.                         Colorado. The Nucla facility consists of               NOX limit of 952 tpy by January 1, 2020,
                                               Specifically, we acknowledge and agree                    one coal-fired steam-driven electric                   do not alter the previously approved 0.5
                                               with the assumptions used to calculate                    generating unit, Unit 4, with a rated                  lb/MMBtu (30-day rolling average)
                                               the two different amortization periods                    electric generating capacity of 110 MW                 emission limit requirement, the closure
                                               for the shutdown scenario. In past SIP                    (gross).                                               of Nucla achieves greater NOX emission
                                               actions, the EPA has measured                                In 2006, Tri-State installed a small-               reductions than the relevant portions of
                                               amortization periods from the projected                   scale SNCR system on Unit 4 that injects               the 2012 SIP, (which did not previously
                                               compliance date to the date of                            anhydrous ammonia to achieve NOX                       include any shutdown date). We
                                               retirement. In this instance, the                         reductions. The SNCR system is used                    therefore propose to approve Colorado’s
                                               compliance date for SCR is August 31,                     when NOX emissions approach 0.4 lb/                    revision related to Nucla.
                                               2021, which would have been required                      MMBtu; rates above this result in mass
                                               under the State’s BART determination                      emissions that approach the annual                     V. Coordination With FLMs
                                               made in conjunction with the 2014                         permitted NOX limit of 1,987.9 tpy (12-                  Class I areas in Colorado are managed
                                               settlement, resulting in an amortization                  month rolling average). Although                       by either the U.S. Forest Service (FS) or
                                               period of four years and four months as                   Colorado, in its 2011 submittal,                       the U.S. National Park Service (NPS). As
                                               reflected in Colorado’s first amortization                determined that full-scale SNCR and                    described in section II.D of this
                                               period scenario (Table 1). For SNCR, the                  SCR were technically feasible for                      proposed rule, the Regional Haze Rule
                                               projected compliance date would be                        reducing NOX emissions at Nucla Unit                   grants the FLMs a special role in the
                                               earlier, thus resulting in a longer                       4, the State determined that neither                   review of regional haze SIPs. Under 40
                                               amortization period, albeit one shorter                   control technology was necessary for                   CFR 51.308(i)(2), Colorado was
                                               than 8 years; the 8-year amortization                     reasonable progress based on the                       obligated to provide the FS and the NPS
                                               period is therefore a conservative                        uncertainty of the control efficiency for              with an opportunity for consultation in
                                               approach that understates the                             SNCR and what Colorado determined                      development of the State’s proposed SIP
                                               annualized costs of both SCR and SNCR.                    would likely be excessive costs                        revisions. Colorado provided the FS and
                                                  When considering the shortened                         associated with SCR. Instead, Colorado                 the NPS with access to the proposed
                                               remaining useful life under either                        determined that Nucla Unit 4 should                    revisions to Regulation Number 3, Part
                                               amortization scenario associated with                     meet an emission limit of 0.5 lb/MMBtu                 F on January 12, 2017.26 The FLMs did
                                               Craig Unit 1 shutting down by                             (30-day rolling average) as expeditiously              not provide any comments on the
                                               December 31, 2025, the EPA finds                          as practicable, but in no event later than             proposed revisions.
                                               Colorado’s determination reasonable                       December 31, 2017, based on
                                               that neither SNCR or SCR is cost                          consideration of the four reasonable                   VI. The EPA’s Proposed Action
                                               effective. Therefore, we are proposing to                 progress factors. The EPA approved this                  In this action, the EPA is proposing to
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                                               approve Colorado’s NOX BART                               emission limit into the SIP on December                approve SIP amendments to Regulation
                                               reassessment that if Craig Unit 1 shuts                   31, 2012, as meeting the relevant                      Number 3, Part F, Section VI, shown in
                                               down by December 31, 2025, neither                        regional haze requirements.                            Table 3, submitted by the State of
                                               SNCR or SCR would be BART due to the                                                                             Colorado on May 26, 2017, addressing
                                               high cost-effectiveness values associated                 B. May 26, 2017 Submittal
                                                                                                                                                                the NOX BART and reasonable progress
                                               with a shortened remaining useful life.                     The May 26, 2017 submittal includes
                                                                                                         the following amendments to the                          26 Email between Colorado and NPS, January
                                                 25 40   CFR part 51, appendix Y.                        Colorado Code of Regulations,                          2017.



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                                               18248                   Federal Register / Vol. 83, No. 81 / Thursday, April 26, 2018 / Proposed Rules

                                               requirements for Craig Unit 1 and            in the Unfunded Mandates Reform Act                               SUMMARY:   The Environmental Protection
                                               Nucla, respectively.                         of 1995 (Pub. L. 104–4);                                          Agency (EPA) is proposing to approve
                                                                                               • Does not have federalism                                     certain portions of a State
                                                TABLE 3—LIST OF COLORADO AMEND- implications as specified in Executive                                        Implementation Plan (SIP) revision to
                                                  MENTS THAT EPA IS PROPOSING TO Order 13132 (64 FR 43255, August 10,                                         address regional haze submitted by the
                                                  APPROVE                                   1999);                                                            Governor of North Dakota on March 3,
                                                                                               • Is not an economically significant                           2010, along with SIP Supplement No. 1
                                                    Amended Sections in May 26, 2017        regulatory action based on health or                              submitted on July 27, 2010, SIP
                                                     Submittal Proposed for Approval        safety risks subject to Executive Order                           Amendment No. 1 submitted on July 28,
                                                                                            13045 (62 FR 19885, April 23, 1997);                              2011 and SIP Supplement No. 2
                                               Regulation Number 3, Part F: VI.A.2 (table);    • Is not a significant regulatory action                       submitted on January 2, 2013
                                                 VI.A.3; VI.A.4; VI.B.2 (table); VI.B.3;    subject to Executive Order 13211 (66 FR                           (collectively, ‘‘the Regional Haze SIP’’).
                                                 VI.B.4; VI.D; VI.E.                        28355, May 22, 2001);                                             Specifically, the EPA is proposing to
                                                                                               • Is not subject to requirements of
                                                                                                                                                              approve the nitrogen oxides (NOX) Best
                                               VII. Incorporation by Reference              Section 12(d) of the National
                                                                                                                                                              Available Retrofit Technology (BART)
                                                  In this rule, the EPA is proposing to     Technology Transfer and Advancement
                                                                                                                                                              determination for Coal Creek Station
                                               include in a final EPA rule regulatory       Act of 1995 (15 U.S.C. 272 note) because
                                                                                                                                                              included in SIP Supplement No. 2. Coal
                                               text that includes incorporation by          application of those requirements would
                                                                                                                                                              Creek Station is owned and operated by
                                               reference. In accordance with                be inconsistent with the Clean Air Act;
                                                                                                                                                              Great River Energy (GRE) and is located
                                               requirements of 1 CFR 51.5, the EPA is       and
                                                                                               • Does not provide the EPA with the                            near Underwood, North Dakota. This
                                               proposing to incorporate by reference                                                                          Regional Haze SIP was submitted to
                                               the amendments described in section          discretionary authority to address, as
                                                                                            appropriate, disproportionate human                               address the requirements of the Clean
                                               VI. The EPA has made, and will                                                                                 Air Act (CAA or ‘‘the Act’’) and our
                                               continue to make, these materials            health or environmental effects, using
                                                                                            practicable and legally permissible                               rules that require states to develop and
                                               generally available through                                                                                    implement air quality protection plans
                                               www.regulations.gov and at the EPA           methods, under Executive Order 12898
                                                                                            (59 FR 7629, February 16, 1994).                                  to reduce visibility impairment in
                                               Region 8 Office (please contact the                                                                            mandatory Class I areas caused by
                                               person identified in the FOR FURTHER            In addition, the SIP is not proposed to
                                                                                            apply on any Indian reservation land or                           emissions of air pollutants from
                                               INFORMATION CONTACT section of this                                                                            numerous sources located over a wide
                                               preamble for more information).              in any other area where the EPA or an
                                                                                            Indian tribe has demonstrated that a                              geographic area (also referred to as the
                                               VIII. Statutory and Executive Order          tribe has jurisdiction. In those areas of                         ‘‘regional haze program’’). States are
                                               Reviews                                      Indian country, the rule does not have                            required to assure reasonable progress
                                                  Under the CAA, the Administrator is       tribal implications and will not impose                           toward the national goal of achieving
                                               required to approve a SIP submission         substantial direct costs on tribal                                natural visibility conditions in Class I
                                               that complies with the provisions of the governments or preempt tribal law as                                  areas. The EPA is taking this action
                                               Act and applicable federal regulations.      specified by Executive Order 13175 (65                            pursuant to section 110 of the CAA.
                                               42 U.S.C. 7410(k); 40 CFR 52.02(a).          FR 67249, November 9, 2000).                                      DATES: Written comments must be
                                               Thus, in reviewing SIP submissions, the                                                                        received on or before May 29, 2018.
                                                                                            List of Subjects in 40 CFR Part 52
                                               EPA’s role is to approve state choices,
                                               provided that they meet the criteria of         Environmental protection, Air                                  ADDRESSES:   Submit your comments,
                                               the CAA. Accordingly, this action            pollution control, Incorporation by                               identified by Docket ID No. EPA–R08–
                                               merely proposes to approve state law as reference, Intergovernmental relations,                                OAR–2010–0406 at https://
                                               meeting federal requirements and does        Nitrogen dioxide, Particulate matter,                             www.regulations.gov. Follow the online
                                               not impose additional requirements           Sulfur oxides.                                                    instructions for submitting comments.
                                               beyond those imposed by state law. For         Authority: 42 U.S.C. 7401 et seq.
                                                                                                                                                              Once submitted, comments cannot be
                                               that reason, this proposed action:                                                                             edited or removed from
                                                                                              Dated: April 16, 2018.                                          www.regulations.gov. The EPA may
                                                  • Is not a significant regulatory action
                                                                                            Debra Thomas,                                                     publish any comment received to the
                                               subject to review by the Office of
                                               Management and Budget under                  Acting Regional Administrator, Region 8.                          public docket. Do not submit
                                               Executive Orders 12866 (58 FR 51735,         [FR Doc. 2018–08622 Filed 4–25–18; 8:45 am]                       electronically any information you
                                               October 4, 1993) and 13563 (76 FR 3821, BILLING CODE 6560–50–P                                                 consider to be Confidential Business
                                               January 21, 2011);                                                                                             Information (CBI) or other information,
                                                  • Is not an Executive Order 13771 (82                                                                       the disclosure of which is restricted by
                                               FR 9339, February 2, 2017) regulatory        ENVIRONMENTAL PROTECTION                                          statute. Multimedia submissions (audio,
                                               action because SIP approvals are             AGENCY                                                            video, etc.) must be accompanied by a
                                               exempted under Executive Order 12866;                                                                          written comment. The written comment
                                                  • Does not impose an information          40 CFR Part 52                                                    is considered the official comment and
                                               collection burden under the provisions       [EPA–R08–OAR–2010–0406; FRL–9976–                                 should include discussion of all points
                                               of the Paperwork Reduction Act (44           56—Region 8]                                                      you wish to make. The EPA will
                                               U.S.C. 3501 et seq.);                                                                                          generally not consider comments or
                                                  • Is certified as not having a            Approval and Promulgation of Air
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                                                                                                                                                              comment contents located outside of the
                                               significant economic impact on a             Quality Implementation Plans; North                               primary submission (i.e., on the web,
                                               substantial number of small entities         Dakota; Regional Haze State                                       cloud, or other file sharing system). For
                                               under the Regulatory Flexibility Act (5      Implementation Plan                                               additional submission methods, the full
                                               U.S.C. 601 et seq.);                         AGENCY: Environmental Protection                                  EPA public comment policy,
                                                  • Does not contain any unfunded           Agency (EPA).                                                     information about CBI or multimedia
                                               mandate or significantly or uniquely                                                                           submissions, and general guidance on
                                                                                            ACTION: Proposed rule.
                                               affect small governments, as described                                                                         making effective comments, please visit


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Document Created: 2018-11-02 08:20:02
Document Modified: 2018-11-02 08:20:02
CategoryRegulatory Information
CollectionFederal Register
sudoc ClassAE 2.7:
GS 4.107:
AE 2.106:
PublisherOffice of the Federal Register, National Archives and Records Administration
SectionProposed Rules
ActionProposed rule.
DatesComments: Written comments must be received on or before May 29, 2018.
ContactJaslyn Dobrahner, Air Program, EPA, Region 8, Mailcode 8P-AR, 1595 Wynkoop Street, Denver, Colorado, 80202- 1129, (303) 312-6252, [email protected]
FR Citation83 FR 18243 
CFR AssociatedEnvironmental Protection; Air Pollution Control; Incorporation by Reference; Intergovernmental Relations; Nitrogen Dioxide; Particulate Matter and Sulfur Oxides

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